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Myotonic dystrophy (DM), the most common dystrophy in adults, is an autosomal dominant disease characterized by a variety of multisystemic features. Two genetically distinct forms of DM are identified - type 1 (DM1), the classic form first described by Steinert, and type 2 (DM2), identified by Ricker. DM1 is caused by trinucleotide expansion of CTG in the myotonic dystrophy protein kinase gene, whereas in DM2 the expansion of tetranucleotide repeats (CCTG) in the zinc finger protein 9 gene was identified. Both mutations are dynamic and are located in non-coding parts of the genes. Phenotype variability of DM1 and DM2 is caused by a molecular mechanism due to mutated RNA toxicity. This paper reviews the clinical features of both types of myotonic dystrophies and summarizes current views on pathogenesis of myotonic dystrophy.
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Which are the types of myotonic dystrophy?
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Two genetically distinct forms of DM are identified - type 1 (DM1), the classic form first described by Steinert, and type 2 (DM2), identified by Ricker.
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Numerous clinical studies have shown that anti-EGFR therapies are effective only in a subset of patients with colorectal cancer. Even though mutations in the KRAS gene have been confirmed as negative predictors of the response to EGFR-targeted therapies, not all KRAS wild-type (wt-KRAS) patients will respond to treatment. Recent studies have demonstrated that additionally wild-type BRAF (wt-BRAF) genotype is required for response to panitumumab or cetuximab, suggesting that BRAF genotype criteria should be used together with KRAS genotype for selecting the patients who are about to benefit from the anti-EGFR therapy. In this study, 239 samples obtained from 215 patients with metastatic colorectal cancer were tested for the presence of the seven most common mutations in the KRAS gene and the V600E mutation in the BRAF gene. Among the tested patients, 53.8% of patients had wt-KRAS genotype and 46.2% were KRAS mutants. Around five percent (5.1%) of the tested patients bore the V600E mutation in BRAF gene. All the patients showing to have the V600E mutation in BRAF were wt-KRAS. The concordance of KRAS and BRAF mutational status between primary and metastatic tumor tissue samples was 100%. We have shown that the proportions of mutated and non-mutated KRAS in Slovene patients, as well as the proportion of V600E mutations in BRAF is similar to genotyping results reported by other authors. The tested seven KRAS mutations on codons 12 and 13 were mutually exclusive with the V600E mutation in the BRAF gene. Summing up the results about the KRAS and the BRAF mutation carriers from our study, the portion of potentially non-responsive patients for the anti-EGFR treatment is 51.3%.
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Which gene(s) should be genotyped in order to prescribe the drug Cetuximab (anti-EGFR)?
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Numerous clinical studies have shown that anti-EGFR therapies are effective only in a subset of patients with colorectal cancer. Even though mutations in the KRAS gene have been confirmed as negative predictors of the response to EGFR-targeted therapies, not all KRAS wild-type (wt-KRAS) patients will respond to treatment. Recent studies have demonstrated that additionally wild-type BRAF (wt-BRAF) genotype is required for response to panitumumab or cetuximab, suggesting that BRAF genotype criteria should be used together with KRAS genotype for selecting the patients who are about to benefit from the anti-EGFR therapy.
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Soft tissue sarcomas are rare tumors that represent a major challenge due to varying clinical presentations and often interdisciplinary treatment concepts. Gold standard for the treatment of localized resectable soft tissue sarcomas is complete surgical removal. In metastatic soft tissue sarcoma, systemic therapy is the treatment of choice. The most active drugs are anthracyclines and ifosfamide. Combination chemotherapy has improved both response rate and progression-free survival at the cost of increased toxicity. Imatinib at a dose of 400 mg/day is the gold standard for patients with advanced or metastatic gastrointestinal stromal tumors (GIST). In patients with a mutation in KIT exon 9, 800 mg/day is the recommended dose. In imatinib refractory or intolerant patients, sunitinib is recommended. Regorafenib has been approved for third-line therapy.
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Is there a role of regorafenib for sarcoma treatment?
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Regorafenib has been approved for third-line therapy.
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The Drosophila neuromuscular junction (NMJ) has recently provided new insights into the roles of various proteins in neurodegenerative diseases including Amyotrophic Lateral Sclerosis (ALS), Spinal Muscular Atrophy (SMA), Multiple Sclerosis (MS) Hereditary Spastic Paraplegia (HSP), and Huntington's Disease (HD). Several developmental signaling pathways including WNT, MAPK and BMP/TGF-β signaling play important roles in the formation and growth of the Drosophila NMJ. Studies of the fly homologues of genes that cause neurodegenerative disease at the NMJ have resulted in a better understanding of the roles of these proteins in vivo. These studies may shed light on the pathological mechanisms of these diseases, with implications for reduced BMP/TGF-β signaling in ALS, SMA and HD and increased signaling in HSP and MS.
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What links developmental pathways to ALS?
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opmental signaling pathways including WNT, MAPK and BMP/TGF-β signaling play important roles in the formation and growth of the Drosophila NMJ. Studies of t
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GC level distributions of a species' nuclear genome, or of its compositional fractions, encode key information on structural and functional properties of the genome and on its evolution. They can be calculated either from absorbance profiles of the DNA in CsCl density gradients at sedimentation equilibrium, or by scanning long contigs of largely sequenced genomes. In the present study, we address the quantitative characterization of the compositional heterogeneity of genomes, as measured by the GC distributions of fixed-length fragments. Special attention is given to mammalian genomes, since their compartmentalization into isochores implies two levels of heterogeneity, intra-isochore (local) and inter-isochore (global). This partitioning is a natural one, since large-scale compositional properties vary much more among isochores than within them. Intra-isochore GC distributions become roughly Gaussian for long fragments, and their standard deviations decrease only slowly with increasing fragment length, unlike random sequences. This effect can be explained by 'long-range' correlations, often overlooked, that are present along isochores.
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Does GC content vary markedly within a given isochore?
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This partitioning is a natural one, since large-scale compositional properties vary much more among isochores than within them.
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With the development of novel targeted therapies, including exon skipping/inclusion and gene replacement therapy, the field of neuromuscular diseases has drastically changed in the last several years. Until 2016, there had been no FDA-approved drugs to treat Duchenne muscular dystrophy (DMD), the most common muscular dystrophy. However, several new personalized therapies, including antisense oligonucleotides eteplirsen for DMD exon 51 skipping and golodirsen and viltolarsen for DMD exon 53 skipping, have been approved in the last 4 years. We are witnessing the start of a therapeutic revolution in neuromuscular diseases. However, the studies also made clear that these therapies are still far from a cure. Personalized genetic medicine for neuromuscular diseases faces several key challenges, including the difficulty of obtaining appropriate cell and animal models and limited its applicability. This Special Issue "Molecular Diagnosis and Novel Therapies for Neuromuscular/Musculoskeletal Diseases" highlights key areas of research progress that improve our understanding and the therapeutic outcomes of neuromuscular diseases in the personalized medicine era.
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What type of DMD can viltolarsen be used for?
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en for DMD exon 51 skipping and golodirsen and viltolarsen for DMD exon 53 skipping, have been approved in the last 4 years. We are witnessing the sta
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Dysregulated microRNA (miRNA) expression contributes to the pathogenesis of hematopoietic malignancies, including chronic lymphocytic leukemia (CLL). However, an understanding of the mechanisms that cause aberrant miRNA transcriptional control is lacking. In this study, we comprehensively investigated the role and extent of miRNA epigenetic regulation in CLL. Genome-wide profiling conducted on 24 CLL and 10 healthy B cell samples revealed global DNA methylation patterns upstream of miRNA sequences that distinguished malignant from healthy cells and identified putative miRNA promoters. Integration of DNA methylation and miRNA promoter data led to the identification of 128 recurrent miRNA targets for aberrant promoter DNA methylation. DNA hypomethylation accounted for more than 60% of all aberrant promoter-associated DNA methylation in CLL, and promoter DNA hypomethylation was restricted to well-defined regions. Individual hyper- and hypomethylated promoters allowed discrimination of CLL samples from healthy controls. Promoter DNA methylation patterns were confirmed in an independent patient cohort, with 11 miRNAs consistently showing an inverse correlation between DNA methylation status and expression level. Together, our findings characterize the role of epigenetic changes in the regulation of miRNA transcription and create a repository of disease-specific promoter regions that may provide additional insights into the pathogenesis of CLL.
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Are microRNA (miR) regulated through DNA methylation of their promoters?
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Integration of DNA methylation and miRNA promoter data led to the identification of 128 recurrent miRNA targets for aberrant promoter DNA methylation
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Cryptochrome 1 and 2 act as essential components of the central and peripheral circadian clocks for generation of circadian rhythms in mammals. Here we show that mouse cryptochrome 2 (mCRY2) is phosphorylated at Ser-557 in the liver, a well characterized peripheral clock tissue. The Ser-557-phosphorylated form accumulates in the liver during the night in parallel with mCRY2 protein, and the phosphorylated form reaches its maximal level at late night, preceding the peak-time of the protein abundance by approximately 4 h in both light-dark cycle and constant dark conditions. The Ser-557-phosphorylated form of mCRY2 is localized in the nucleus, whereas mCRY2 protein is located in both the cytoplasm and nucleus. Importantly, phosphorylation of mCRY2 at Ser-557 allows subsequent phosphorylation at Ser-553 by glycogen synthase kinase-3beta (GSK-3beta), resulting in efficient degradation of mCRY2 by a proteasome pathway. As assessed by phosphorylation of GSK-3beta at Ser-9, which negatively regulates the kinase activity, GSK-3beta exhibits a circadian rhythm in its activity with a peak from late night to early morning when Ser-557 of mCRY2 is highly phosphorylated. Altogether, the present study demonstrates an important role of sequential phosphorylation at Ser-557/Ser-553 for destabilization of mCRY2 and illustrates a model that the circadian regulation of mCRY2 phosphorylation contributes to rhythmic degradation of mCRY2 protein.
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What is the function of cryptochrome-1 in mouse?
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Cryptochrome 1 and 2 act as essential components of the central and peripheral circadian clocks for generation of circadian rhythms in mammals
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Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest red cell enzymopathy in humans and has an X-linked inheritance. It has been reported from India more than 30 years ago and the prevalence varies from 0-27% in different caste, ethnic and linguistic groups. The major clinical manifestations are drug induced hemolytic anemia, neonatal jaundice and chronic non-spherocytic hemolytic anemia. Individuals with G6PD deficiency have a selective advantage against falciparum malaria. Thirteen biochemically characterized variants have been reported from India. At the molecular level, G6PD Mediterranean is the most common deficient variant in the caste groups whereas, G6PD Orissa is more prevalent among the tribal of India. The third common variant seen in India is G6PD Kerala-Kalyan.
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Has Glucose-6-phosphate dehydrogenase (G6PD) deficiency an X-linked inheritance?
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Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest red cell enzymopathy in humans and has an X-linked inheritance
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The FaceBase Consortium consists of ten interlinked research and technology projects whose goal is to generate craniofacial research data and technology for use by the research community through a central data management and integrated bioinformatics hub. Funded by the National Institute of Dental and Craniofacial Research (NIDCR) and currently focused on studying the development of the middle region of the face, the Consortium will produce comprehensive datasets of global gene expression patterns, regulatory elements and sequencing; will generate anatomical and molecular atlases; will provide human normative facial data and other phenotypes; conduct follow up studies of a completed genome-wide association study; generate independent data on the genetics of craniofacial development, build repositories of animal models and of human samples and data for community access and analysis; and will develop software tools and animal models for analyzing and functionally testing and integrating these data. The FaceBase website (http://www.facebase.org) will serve as a web home for these efforts, providing interactive tools for exploring these datasets, together with discussion forums and other services to support and foster collaboration within the craniofacial research community.
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What is the purpose of the FaceBase consortium?
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The FaceBase website (http://www.facebase.org) will serve as a web home for these efforts, providing interactive tools for exploring these datasets, together with discussion forums and other services to support and foster collaboration within the craniofacial research community.
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Drug-induced adverse reactions, especially type B reactions, represent a major clinical problem. They also impart a significant degree of uncertainty into drug development because they are often not detected until the drug has been released onto the market. Type B reactions are also termed idiosyncratic drug reactions by many investigators due to their unpredictable nature and our lack of understanding of the mechanisms involved. It is currently believed that the majority of these reactions are immune-mediated and are caused by immunogenic conjugates formed from the reaction of a reactive metabolite of a drug with cellular proteins. It has been shown that most drugs associated with idiosyncratic reactions form reactive metabolites to some degree. Covalent binding of reactive metabolites to cellular proteins has also been shown in many cases. However, studies to reveal the role of reactive metabolites and their protein-adducts in the mechanism of drug-induced idiosyncratic reactions are lacking. This review will focus on our current understanding and speculative views on how a reactive metabolite of a drug might ultimately lead to immune-mediated toxicity.
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What are reactive metabolites?
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This review will focus on our current understanding and speculative views on how a reactive metabolite of a drug might ultimately lead to immune-mediated toxicity
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Polyphenols constitute a distinct group of natural compounds of medicinal importance exhibiting wide range of physiological activities as antioxidant, immunestimulant, antitumor and antiparasitic. Yellow fever and dengue fever are mosquito-borne infectious diseases transmitted by Aedes aegyptii, the presence of yellow fever in Sudan and dengue fever in Saudi Arabia are threats to Egypt with the reemerging of Ae. aegyptii in Southern Egypt, larvae control is feasible than flying adults. This work was conducted targeting estimation of the relative levels of total phenolic content, antioxidant potential and larvicidal activity of 110 selected Egyptian plants. The highest total phenolic contents were estimated in aqueous extracts of Coronilla scorpioides L., Forsskaolea tenacissima L., Crataegus sinaica Boiss., Pistacia khinjuk Boiss. and Loranthus acacia Benth.; they were 916.70 +/- 4.80, 813.70 +/- 4.16, 744.90 +/- 4.93, 549.00 +/- 3.93& 460.80 +/- 4.02 mg% while those of methanol extracts were estimated in Coronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Loranthus acacia and Pistacia khinjuk, they were 915.60-4.86, 664.60 +/- 4.16, 659.30 +/- 4.80, 590.80 +/- 4.49 & 588.00 +/- 3.85 mg% respectively. Investigation of the antioxidant potentials revealed that the most potent plants were Co-ronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Pistacia khinjuk and Loranthus acacia with calculated values of 454.80 +/- 4.83, 418.4 +/- 4.16, 399.10 +/- 4.90, 342.5 +/- 2.72 & 239.7 +/- 2.91% for aqueous extracts and 452.9 +/- 4.94, 389.6 +/- 4.6, 378.48 +/- 3.84, 352.3 +/- 3.06 & 346.5 +/- 2.98% for methanol extracts respectively while screening of larvicidal activity proved that Coronilla scorpioides, Forsskaolea tenacissima, Crataegus sinaica, Pistacia khinjuk and Loranthus acacia exhibited highest potency calculated as 22.53 +/- 2.01, 23.85 +/- 2.07, 28.17 +/- 2.06, 31.60 +/- 2.93 & 39.73 +/- 4.58 mg% aqueous extracts and 18.53 +/- 1.95, 18.8 +/- 1.67, 20.17 +/- 1.85, 23.28 +/- 2.7 & 28.48 +/- 3.9 mg% methanol ones respectively.
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How is yellow fever virus transmitted?
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fever and dengue fever are mosquito-borne infectious diseases transmitted by Aedes aegyptii, the presence of yellow fever in Sudan and dengue fever in Saudi Arabia are threats to Egypt with the reemerging of Ae. aegyptii in Southern Egypt, larvae control is feasible than flying adults
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Multiple regulatory elements distant from their targets on the linear genome can influence the expression of a single gene through chromatin looping. Chromosome conformation capture implemented in Hi-C allows for genome-wide agnostic characterization of chromatin contacts. However, detection of functional enhancer-promoter interactions is precluded by its effective resolution that is determined by both restriction fragmentation and sensitivity of the experiment. Here we develop a capture Hi-C (cHi-C) approach to allow an agnostic characterization of these physical interactions on a genome-wide scale. Single-nucleotide polymorphisms associated with complex diseases often reside within regulatory elements and exert effects through long-range regulation of gene expression. Applying this cHi-C approach to 14 colorectal cancer risk loci allows us to identify key long-range chromatin interactions in cis and trans involving these loci.
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What is the basis of the capture Hi-C experimental protocol?
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Here we develop a capture Hi-C (cHi-C) approach to allow an agnostic characterization of these physical interactions on a genome-wide scale.
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Neutrophil extracellular traps (NETs) represent an important defense mechanism against microorganisms. Clearance of NETs is impaired in a subset of patients with systemic lupus erythematosus, and NETosis is increased in neutrophils and, particularly, in low-density granulocytes derived from lupus patients. NETs are toxic to the endothelium, expose immunostimulatory molecules, activate plasmacytoid dendritic cells, and may participate in organ damage through incompletely characterized pathways. To better understand the role of NETs in fostering dysregulated inflammation, we examined inflammasome activation in response to NETs or to LL-37, an antibacterial protein externalized on NETs. Both NETs and LL-37 activate caspase-1, the central enzyme of the inflammasome, in both human and murine macrophages, resulting in release of active IL-1β and IL-18. LL-37 activation of the NLRP3 inflammasome utilizes P2X7 receptor-mediated potassium efflux. NET and LL-37-mediated activation of the inflammasome is enhanced in macrophages derived from lupus patients. In turn, IL-18 is able to stimulate NETosis in human neutrophils. These results suggest that enhanced formation of NETs in lupus patients can lead to increased inflammasome activation in adjacent macrophages. This leads to release of inflammatory cytokines that further stimulate NETosis, resulting in a feed-forward inflammatory loop that could potentially lead to disease flares and/or organ damage.
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What is the role of NETs in systemic lupus erythematosus?
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Neutrophil extracellular traps (NETs) represent an important defense mechanism against microorganisms. Clearance of NETs is impaired in a subset of patients with systemic lupus erythematosus, and NETosis is increased in neutrophils and, particularly, in low-density granulocytes derived from lupus patients. NETs are toxic to the endothelium, expose immunostimulatory molecules, activate plasmacytoid dendritic cells, and may participate in organ damage through incompletely characterized pathways.
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The Ascomycete pathogen Fusarium graminearum can infect all cereal species and lower grain yield, quality and safety. The fungus can also cause disease on Arabidopsis thaliana. In this study, the disease-causing ability of two F. graminearum mutants was analysed to further explore the parallels between the wheat (Triticum aestivum) and Arabidopsis floral pathosystems. Wild-type F. graminearum (strain PH-1) and two isogenic transformants lacking either the mitogen-activated protein kinase MAP1 gene or the trichodiene synthase TRI5 gene were individually spray- or point-inoculated onto Arabidopsis and wheat floral tissue. Disease development was quantitatively assessed both macroscopically and microscopically and deoxynivalenol (DON) mycotoxin concentrations determined by enzyme-linked immunosorbent assay (ELISA). Wild-type strain inoculations caused high levels of disease in both plant species and significant DON production. The map1 mutant caused minimal disease and DON accumulation in both hosts. The tri5 mutant, which is unable to produce DON, exhibited reduced pathogenicity on wheat ears, causing only discrete eye-shaped lesions on spikelets which failed to infect the rachis. By contrast, the tri5 mutant retained full pathogenicity on Arabidopsis floral tissue. This study reveals that DON mycotoxin production is not required for F. graminearum to colonize Arabidopsis floral tissue.
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The pathogen Fusarium graminearum affects what type of plant species?
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The Ascomycete pathogen Fusarium graminearum can infect all cereal species and lower grain yield, quality and safety.
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Polyadenylation is a process of endonucleolytic cleavage of the mRNA, followed by addition of up to 250 adenosine residues to the 3' end of the mRNA. Polyadenylation is essential for eukaryotic mRNA expression, and CstF-64 is a subunit of the CstF polyadenylation factor that is required for accurate polyadenylation. We discovered that there are two forms of the CstF-64 protein in mammalian male germ cells, one of which (CstF-64) is expressed in all tissues, the other of which (tauCstF-64) is expressed only in male germ cells and in brain (albeit at significantly lower levels in the brain). Therefore, we were surprised to find that, using reverse transcription-PCR, cDNA cloning, and RNA blot analyses, tauCstF-64 mRNA was expressed at higher levels in brain than in testis. Also, tauCstF-64 mRNA was expressed at lower but detectable levels in all tissues tested, including epididymis, heart, kidney, liver, lung, muscle, ovary, spleen, thymus, and uterus. These results suggest the hypothesis that tauCstF-64 mRNA is regulated at the translational or post-translational level.
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Is polyadenylation a process that stabilizes a protein by adding a string of Adenosine residues to the end of the molecule?
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Polyadenylation is a process of endonucleolytic cleavage of the mRNA, followed by addition of up to 250 adenosine residues to the 3' end of the mRNA.
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Eph receptor tyrosine kinases and their ligands, ephrins, mediate neurodevelopmental processes such as boundary formation, axon guidance, vasculogenesis, and cell migration. We determined the expression profiles of the Eph family members in five glioma cell lines under migrating and nonmigrating conditions. EphB2 mRNA was overexpressed in all five during migration (1.2-2.8-fold). We found abundant EphB2 protein as well as strong phosphorylation of EphB2 in migrating U87 cells. Confocal imaging showed EphB2 localized in lamellipodia of motile U87 cells. Treatment with ephrin-B1/Fc chimera stimulated migration and invasion of U87, whereas treatment with a blocking EphB2 antibody significantly inhibited migration and invasion. Forced expression of EphB2 in U251 cells stimulated cell migration and invasion and diminished adhesion concomitant with the tyrosine phosphorylation of EphB2. U251 stably transfected with EphB2 showed more scattered and more pronounced invasive growth in an ex vivo rat brain slice. In human brain tumor specimens, EphB2 expression was higher in glioblastomas than in low-grade astrocytomas or normal brain; patterns of phosphorylated EphB2 matched the expression levels. Laser capture microdissection of invading glioblastoma cells revealed elevated EphB2 mRNA (1.5-3.5-fold) in 7 of 7 biopsy specimens. Immunohistochemistry demonstrated EphB2 localization primarily in glioblastoma cells (56 of 62 cases) and not in normal brain. This is the first demonstration that migrating glioblastoma cells overexpress EphB2 in vitro and in vivo; glioma migration and invasion are promoted by activation of EphB2 or inhibited by blocking EphB2. Dysregulation of EphB2 expression or function may underlie glioma invasion.
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Do ephrins play a role in brain cancer?
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migrating glioblastoma cells overexpress EphB2 in vitro and in vivo; glioma migration and invasion are promoted by activation of EphB2 or inhibited by blocking EphB2. Dysregulation of EphB2 expression or function may underlie glioma invasion
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Sudden cardiac death (SCD) in young athletes is generally caused by inherited cardiac disorders. While these events are relatively few compared to other cardiac deaths, they are tragic in that death occurs in a young, otherwise healthy person. The genetic abnormalities most associated with SCD are hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, long QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia. As a result of growing awareness that these deaths can be prevented, guidelines have been issued in both Europe and the United States to help screen and determine qualification for young persons who want to participate in competitive athletics. There remains debate on the how extensive screening should be, in particular over the use of the 12-lead electrocardiogram (ECG), with European guidelines mandating ECG and United States guidelines not recommending routine use of the ECG.
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Is long QT syndrome a cause for sudden cardiac death in athletes?
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The genetic abnormalities most associated with SCD are hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, long QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia.
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Hirschsprung's disease (HSCR) is a fairly frequent cause of intestinal obstruction in children. It is characterized as a sex-linked heterogonous disorder with variable severity and incomplete penetrance giving rise to a variable pattern of inheritance. Although Hirschsprung's disease occurs as an isolated phenotype in at least 70% of cases, it is not infrequently associated with a number of congenital abnormalities and associated syndromes, demonstrating a spectrum of congenital anomalies. Certain of these syndromic phenotypes have been linked to distinct genetic sites, indicating underlying genetic associations of the disease and probable gene-gene interaction, in its pathogenesis. These associations with HSCR include Down's syndrome and other chromosomal anomalies, Waardenburg syndrome and other Dominant sensorineural deafness, the Congenital Central Hypoventilation and Mowat-Wilson and other brain-related syndromes, as well as the MEN2 and other tumour associations. A number of other autosomal recessive syndromes include the Shah-Waardenburg, the Bardet-Biedl and Cartilage-hair hypoplasia, Goldberg-Shprintzen syndromes and other syndromes related to cholesterol and fat metabolism among others. The genetics of Hirschsprung's disease are highly complex with the majority of known genetic sites relating to the main susceptibility pathways (RET an EDNRB). Non-syndromic non-familial, short-segment HSCR appears to represent a non-Mendelian condition with variable expression and sex-dependent penetrance. Syndromic and familial forms, on the other hand, have complex patterns of inheritance and being reported as autosomal dominant, recessive and polygenic patterns of inheritance. The phenotypic variability and incomplete penetrance observed in Hirschsprung's disease could also be explained by the involvement of modifier genes, especially in its syndromic forms. In this review, we look at the chromosomal and Mendelian associations and their underlying signalling pathways, to obtain a better understanding of the pathogenetic mechanisms involved in developing aganglionosis of the distal bowel.
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What is the common feature in congenital central hypoventilation and Mowat-Wilson syndromes?
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These associations with HSCR include Down's syndrome and other chromosomal anomalies, Waardenburg syndrome and other Dominant sensorineural deafness, the Congenital Central Hypoventilation and Mowat-Wilson and other brain-related syndromes, as well as the MEN2 and other tumour associations.
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The different XK mutations may have different effects upon the XK gene product and thus may account for the variable phenotype.
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Mutation of which gene is associated with McLeod syndrome?
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The different XK mutations may have different effects upon the XK gene product and thus may account for the variable phenotype.
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Netrin-1 is a secreted protein that directs long-range axon guidance during early stages of neural circuit formation and continues to be expressed in the mammalian forebrain during the postnatal period of peak synapse formation. Here we demonstrate a synaptogenic function of netrin-1 in rat and mouse cortical neurons and investigate the underlying mechanism. We report that netrin-1 and its receptor DCC are widely expressed by neurons in the developing mammalian cortex during synapse formation and are enriched at synapses in vivo. We detect DCC protein distributed along the axons and dendrites of cultured cortical neurons and provide evidence that newly translated netrin-1 is selectively transported to dendrites. Using gain and loss of function manipulations, we demonstrate that netrin-1 increases the number and strength of excitatory synapses made between developing cortical neurons. We show that netrin-1 increases the complexity of axon and dendrite arbors, thereby increasing the probability of contact. At sites of contact, netrin-1 promotes adhesion, while locally enriching and reorganizing the underlying actin cytoskeleton through Src family kinase signaling and m-Tor-dependent protein translation to locally cluster presynaptic and postsynaptic proteins. Finally, we demonstrate using whole-cell patch-clamp electrophysiology that netrin-1 increases the frequency and amplitude of mEPSCs recorded from cortical pyramidal neurons. These findings identify netrin-1 as a synapse-enriched protein that promotes synaptogenesis between mammalian cortical neurons.
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Is Netrin-1 a secreted protein?
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Netrin-1 is a secreted protein that directs long-range axon guidance during early stages of neural circuit formation and continues to be expressed in the mammalian forebrain during the postnatal period of peak synapse formation.
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Low-intensity blood flow restricted (LI-BFR) resistance training has been shown to produce comparable increases in muscle hypertrophy to traditional high-intensity (HI) resistance training. However, a comparison of the acute vascular responses between the two types of exercise has not been made. The purpose of this study is to compare the acute vascular responses of HI, low-intensity (LI), and LI-BFR resistance exercise. Using a randomized, cross-over design, 11 young (28 ± 5 years) males completed three acute resistance exercise bouts (HI, LI and LI-BFR). Before (Pre), and starting at 15- and 45-min after each exercise bout, large (LAEI) and small (SAEI) artery compliance and calf blood flow were assessed. Calf blood flow was normalized per unit pressure as calf vascular conductance (CVC). Repeated measures (condition × time) ANOVA revealed a main time effect for LAEI and a main condition effect for SAEI. LAEI increased following exercise but returned to baseline at 45-min post. SAEI was greater during the HI condition compared to the LI or LI-BFR conditions. There was a significant condition × time interaction for CVC. CVC was elevated at 15- and 45-min post during the HI condition and at 15-min following the LI condition. CVC was not altered following the LI-BFR condition. These results suggest that HI, LI, and LI-BFR resistance exercise cause similar acute increases in large artery compliance but HI causes greater increases in small artery compliance and calf vascular conductance than LI or LI-BFR resistance exercise.
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Is resistance training usually associated with increasing muscle hypertrophy?
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Low-intensity blood flow restricted (LI-BFR) resistance training has been shown to produce comparable increases in muscle hypertrophy to traditional high-intensity (HI) resistance training. Ho
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Preeclampsia is a pregnancy-specific disorder, of which one of its major subtypes, the placental subtype is considered a response to an ischemic placental environment, impacting fetal growth and pregnancy outcome. Inflammatory immune responses have been linked to metabolic and inflammatory disorders as well as reproductive failures. In healthy pregnancy, immune regulatory mechanisms prevent excessive systemic inflammation. However, in preeclampsia, the regulation of immune responses is disrupted as a result of aberrant activation of innate immune cells and imbalanced differentiation of T-helper cell subsets creating a cytotoxic environment . Recognition events that facilitate immune interaction between maternal decidual T cells, NK cells, and cytotrophoblasts are considered an indirect cause of the incomplete remodeling of spiral arteries in preeclampsia. The mechanisms involved include the activation of immune cells and the subsequent secretion of cytokines and placental growth factors affecting trophoblast invasion, angiogenesis, and eventually placentation. In this review, we focus on the role of excessive systemic inflammation as the result of a dysregulated immune system in the development of preeclampsia. These include insufficient control of inflammation, failure of tolerance toward paternal antigens at the fetal-maternal interface, and subsequent over- or insufficient activation of immune mediators. It is also possible that external stimuli, such as bacterial endotoxin, may contribute to the excessive systemic inflammation in preeclampsia by stimulating the release of pro-inflammatory cytokines. In conclusion, a disrupted immune system might be a predisposing factor or result of placental oxidative stress or excessive inflammation in preeclampsia. Preeclampsia can thus be considered a hyperinflammatory state associated with defective regulation of the immune system proposed as a key element in the pathological events of the placental subtype of this disorder.
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Is disruption of immune regulation mechanisms associated with adverse pregnancy outcomes, including preeclampsia (PE)?
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s review, we focus on the role of excessive systemic inflammation as the result of a dysregulated immune system in the development of preeclampsia. These
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Ryanodine receptor (RyR) is a Ca(2+) channel that mediates Ca(2+) release from intracellular stores. Altered Ca(2+) homeostasis in skeletal muscle which usually occurs as a result of point mutations in type 1 RyR1 (RyR1) is a key molecular event triggering malignant hyperthermia (MH). There are three RyR isoforms, and we herein show, for the first time, that human dendritic cells (DCs) preferentially express RyR1 mRNA among them. The RyR activator, 4-chloro-m-cresol (4CmC), induced Ca(2+) release in DCs, and this response was eliminated by dantrolene, an inhibitor of the RyR1, and was unaffected by xestospongin C, a selective inhibitor of IP(3) receptor. Activation of RyR1 reduced LPS-induced IL-10 production, promoted the expression of HLA-DR and CD86, and thereby exhibited an improved capacity to stimulate allogeneic T cells. These findings demonstrate that RyR1-mediated calcium signaling modifies diverse DC responses and suggest the feasibility of using DC preparations for the diagnosis of MH.
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How many and which are the different isoforms for the ryanodine receptor?
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There are three RyR isoforms,
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IDH1/2 mutation is the most frequent genomic alteration found in gliomas, affecting 40% of these tumors and is one of the earliest alterations occurring in gliomagenesis. We investigated a series of 1305 gliomas and showed that IDH mutation is almost constant in 1p19q codeleted tumors. We found that the distribution of IDH1(R132H) , IDH1(nonR132H) , and IDH2 mutations differed between astrocytic, mixed, and oligodendroglial tumors, with an overrepresentation of IDH2 mutations in oligodendroglial phenotype and an overrepresentation of IDH1(nonR132H) in astrocytic tumors. We stratified grade II and grade III gliomas according to the codeletion of 1p19q and IDH mutation to define three distinct prognostic subgroups: 1p19q and IDH mutated, IDH mutated--which contains mostly TP53 mutated tumors, and none of these alterations. We confirmed that IDH mutation with a hazard ratio = 0.358 is an independent prognostic factor of good outcome. These data refine current knowledge on IDH mutation prognostic impact and genotype-phenotype associations.
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The 1p19q co-deletion is associated with what types of tumors?
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We investigated a series of 1305 gliomas and showed that IDH mutation is almost constant in 1p19q codeleted tumors.
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The interaction of DNA with proteins in the context of chromatin has to be tightly regulated to achieve so different tasks as packaging, transcription, replication and repair. The very rapid and transient post-translational modification of proteins by poly(ADP-ribose) has been shown to take part in all four. Originally identified as immediate cellular answer to a variety of genotoxic stresses, already early data indicated the ability of this highly charged nucleic acid-like polymer to modulate nucleosome structure, the basic unit of chromatin. At the same time the enzyme responsible for synthesizing poly(ADP-ribose), the zinc-finger protein poly(ADP-ribose) polymerase-1 (PARP1), was shown to control transcription initiation as basic factor TFIIC within the RNA-polymerase II machinery. Later research focused more on PARP-mediated regulation of DNA repair and cell death, but in the last few years, transcription as well as chromatin modulation has re-appeared on the scene. This review will discuss the impact of PARP1 on transcription and transcription factors, its implication in chromatin remodeling for DNA repair and probably also replication, and its role in controlling epigenetic events such as DNA methylation and the functionality of the insulator protein CCCTC-binding factor.
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How is CTCF activated post-translationally?
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The very rapid and transient post-translational modification of proteins by poly(ADP-ribose) has been shown to take part in all four.
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Huntington's disease (HD) is caused by a genetic mutation that results in polyglutamine expansion in the N-terminal regions of huntingtin. As a result, this polyQ expansion leads to the misfolding and aggregation of mutant huntingtin as well as age-dependent neurodegeneration. The genetic mutation in HD allows for generating a variety of animal models that express different forms of mutant huntingtin and show differential pathology. Studies of these animal models have provided an important insight into the pathogenesis of HD. Mouse models of HD include transgenic mice, which express N-terminal or full-length mutant huntingtin ubiquitously or selectively in different cell types, and knock-in mice that express full-length mutant Htt at the endogenous level. Large animals, such as pig, sheep, and monkeys, have also been used to generate animal HD models. This review focuses on the different features of commonly used transgenic HD mouse models as well as transgenic large animal models of HD, and also discusses how to use them to identify potential therapeutics. Since HD shares many pathological features with other neurodegenerative diseases, identification of therapies for HD would also help to develop effective treatment for different neurodegenerative diseases that are also caused by protein misfolding and occur in an age-dependent manner.
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What gene is mutated in Huntington's disease?
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Huntington's disease (HD) is caused by a genetic mutation that results in polyglutamine expansion in the N-terminal regions of huntingtin.
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The transition from a specified germ cell to a population of pluripotent cells occurs rapidly following fertilization. During this developmental transition, the zygotic genome is largely transcriptionally quiescent and undergoes significant chromatin remodeling. In Drosophila, the DNA-binding protein Zelda (also known as Vielfaltig) is required for this transition and for transcriptional activation of the zygotic genome. Open chromatin is associated with Zelda-bound loci, as well as more generally with regions of active transcription. Nonetheless, the extent to which Zelda influences chromatin accessibility across the genome is largely unknown. Here we used formaldehyde-assisted isolation of regulatory elements to determine the role of Zelda in regulating regions of open chromatin in the early embryo. We demonstrate that Zelda is essential for hundreds of regions of open chromatin. This Zelda-mediated chromatin accessibility facilitates transcription-factor recruitment and early gene expression. Thus, Zelda possesses some key characteristics of a pioneer factor. Unexpectedly, chromatin at a large subset of Zelda-bound regions remains open even in the absence of Zelda. The GAGA factor-binding motif and embryonic GAGA factor binding are specifically enriched in these regions. We propose that both Zelda and GAGA factor function to specify sites of open chromatin and together facilitate the remodeling of the early embryonic genome.
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Is the zelda transcription factor a chromatin remodeller?
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Open chromatin is associated with Zelda-bound loci, as well as more generally with regions of active transcriptio
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The generalized exocrinopathy cystic fibrosis (CF) is the most common severe genetic disease in Caucasian populations. A panel of more than 700 chromosomes from German and Turkish CF patients was screened for disease-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene by chemical cleavage of mismatch, single strand conformation polymorphism, restriction analysis and direct sequencing of genomic DNA amplified by polymerase chain reaction. Besides the major 3-bp deletion, delta F508 that was found on 73% of German CF chromosomes, more than 50 other missense, nonsense, frame-shift, and splice-site mutations have already been identified. In general, a CFTR mutation is linked with a single 10-marker haplotype which indicates that in most cases a particular mutation spread from a common ancestor. The comparison of mutation genotypes with the disease phenotype emphasized the causative role of the type and localization of the CFTR mutation for clinical course and prognosis. Pancreatic status and the risk of colonization of airways with opportunistic pathogens are genetically determined. Most patients who are harbouring mutations in the nucleotide binding folds were suffering from severe CF disease. Mild or even aberrant forms of CF were observed for many missense mutations located in the putative transmembrane domains or for mutations that are expected to result in a truncated protein of half of wild-type CFTR.
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Which is the most common CFTR mutation in Caucasians?
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Besides the major 3-bp deletion, delta F508 that was found on 73% of German CF chromosomes, more than 50 other missense, nonsense, frame-shift, and splice-site mutations have already been identified.
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Multiple myeloma (MM) is a plasma cell neoplasm that results in over 11,000 deaths in the United States annually. The backbone therapy for the treatment of MM patients almost always includes combinations with corticosteroids such as dexamethasone (DEX). We found that DEX in combination with selinexor, an inhibitor of exportin-1 (XPO1) activity, synergistically inhibits the mTOR pathway and subsequently promotes cell death in MM cells. Specifically, we show that selinexor induces the expression of the glucocorticoid receptor (GR) and when combined with dexamethasone increases GR transcriptional activity. Moreover, we found that key downstream targets of the mTOR pathway are deregulated by the combination and identified a mechanism in which GR enhances the expression of REDD1 in GR positive cells while suppressing mTOR activity and cell viability. While the single agent activity of selinexor in MM cells appears to be GR-independent, synergy with DEX depends on GR expression. These data suggest that patients with tumor cells that are GR positive will benefit substantially from the combination. The current findings are consistent with the beneficial therapeutic outcome in patients with MM when treated with the combination of selinexor and DEX. In addition, they provide a rationale for testing GR and REDD1 as predictive and prognostic markers of response, respectively, for patients treated with this beneficial combination.
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Is Selinexor effective for multiple myeloma?
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We found that DEX in combination with selinexor, an inhibitor of exportin-1 (XPO1) activity, synergistically inhibits the mTOR pathway and subsequently promotes cell death in MM cells.
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DOOR syndrome (deafness, onychodystrophy, osteodystrophy, and mental retardation) is a rarely described disorder with less than 35 reports in the literature. The hallmarks of the syndrome, represented in the DOOR acronym, include sensorineural hearing loss, hypoplastic or absent nails on the hands and feet, small or absent distal phalanges of the hands and feet, and mental retardation. The purpose of our communication is to report on an additional patient with DOOR syndrome, delineate common as well as less frequent manifestations of DOOR syndrome, bring attention to the under appreciated facial features in DOOR syndrome, document the natural history of this disorder, and propose a suggested workup of those suspected of DOOR syndrome. DOOR syndrome is associated with characteristic, coarse facial features with large nose with wide nasal bridge, bulbous tip and anteverted nares, a long prominent philtrum and downturned corners of the mouth. The natural history is one of a deteriorative course, with progressive neurological manifestations including sensorineural deafness, seizures from infancy, optic atrophy, and a peripheral polyneuropathy. The majority of patients with DOOR syndrome have elevated levels of 2-oxoglutarate in the urine and plasma. In this report, we present a newborn with manifestations consistent with DOOR syndrome and a progressive clinical course. A comprehensive literature review reveals 32 patients with DOOR syndrome. In conclusion, DOOR syndrome is a neurometabolic disorder with recognizable facial features and a progressive natural history.
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List features of the DOOR syndrome.
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The hallmarks of the syndrome, represented in the DOOR acronym, include sensorineural hearing loss, hypoplastic or absent nails on the hands and feet, small or absent distal phalanges of the hands and feet, and mental retardation.
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Oncogenic activation of the mitogen-activated protein (MAP) kinase cascade in murine fibroblasts initiates a senescence-like cell cycle arrest that depends on the ARF/p53 tumor suppressor pathway. To investigate whether p53 is sufficient to induce senescence, we introduced a conditional murine p53 allele (p53(val135)) into p53-null mouse embryonic fibroblasts and examined cell proliferation and senescence in cells expressing p53, oncogenic Ras, or both gene products. Conditional p53 activation efficiently induced a reversible cell cycle arrest but was unable to induce features of senescence. In contrast, coexpression of oncogenic ras or activated mek1 with p53 enhanced both p53 levels and activity relative to that observed for p53 alone and produced an irreversible cell cycle arrest that displayed features of cellular senescence. p19(ARF) was required for this effect, since p53(-/-) ARF(-/-) double-null cells were unable to undergo senescence following coexpression of oncogenic Ras and p53. Although the levels of exogenous p53 achieved in ARF-null cells were relatively low, the stabilizing effects of p19(ARF) on p53 could not explain the cooperation between oncogenic Ras and p53 in promoting senescence. Hence, enforced p53 expression without oncogenic ras in p53(-/-) mdm2(-/-) double-null cells produced extremely high p53 levels but did not induce senescence. Taken together, our results indicate that oncogenic activation of the MAP kinase pathway in murine fibroblasts converts p53 into a senescence inducer through both quantitative and qualitative mechanisms.
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Which oncogenes are able to induce cellular senescence?
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In contrast, coexpression of oncogenic ras or activated mek1 with p53 enhanced both p53 levels and activity relative to that observed for p53 alone and produced an irreversible cell cycle arrest that displayed features of cellular senescence.
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Metastatic urothelial carcinoma (UC) remains an aggressive disease associated with limited treatment options and a reduced survival. In spite of this, the first-line treatment based on platinum-based combinations has remained virtually unchanged for the last 20-30 years. Similarly, before the advent of the immune checkpoint inhibitors, there were no FDA-approved drugs for second-line therapy. In the last few years, impressive signs of anti-tumor activity have been reported with several immunotherapy agents targeting the programmed cell death-1 (PD-1) pathway. Avelumab, a PD-1 ligand (PD-L1) inhibitor, is currently being investigated for the treatment of UC. Areas covered: This article will review the pharmacological characteristics of avelumab, the efficacy studies which led to its approval, its safety profile, as well as its place within the management of urothelial carcinoma with immunotherapy. For that matter, we undertook a literature review of all the studies assessing the pharmacology of avelumab and its efficacy within clinical trials. Expert commentary: Avelumab has shown promising antitumor activity and a manageable safety profile in patients with UC. Its dual mechanism of action, blocking the interaction between PD-L1 and PD-1 and promoting antibody-dependent cell-mediated cytotoxicity could potentially be of great interest since it could produce synergistic clinical efficacy.
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Is avelumab effective for bladder cancer?
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Avelumab, a PD-1 ligand (PD-L1) inhibitor, is currently being investigated for the treatment of UC. Areas covered: This article will review the pharmacological characteristics of avelumab, the efficacy studies which led to its approval, its safety profile, as well as its place within the management of urothelial carcinoma with immunotherapy.
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Weight-restored patients with anorexia nervosa (AN) respond favorably to the selective serotonin reuptake inhibitor fluoxetine, which justifies association studies of the serotonin transporter gene (SLC6A4, alias SERT) and AN. Case-control studies suggest that the least transcriptionally active allele of the SERT gene promoter polymorphism (5-HTTLPR) has an increased frequency in AN patients. However, this finding was not replicated with 55 trios (AN child+parents) and the transmission disequilibrium test (TDT). To clarify the role of the 5-HTTLPR in susceptibility to AN, we used the TDT and 106 Australian trios to provide 93% power to detect a genotypic relative risk (GRR) of 2.0. Our results were negative for this GRR (McNemar's chi(2)=0.01, df=1, p=0.921, odds ratio 1.0, 95% CI 0.7-1.5). Additionally, we found no association with AN females, AN subtype, age at onset, or minimum BMI. We then performed the first reported investigation of epistasis between the SERT gene and norepinephrine transporter gene (SLC6A2, alias NET) in AN, as an earlier study suggested that atypical AN responds to the dual serotonin-norepinephrine reuptake inhibitor venlafaxine. We observed no epistasis between the 5-HTTLPR and a polymorphism within the NET gene promoter polymorphic region (NETpPR) (chi(2)=0.48, df=1, p=0.490). Although 5-HTTLPR modulates serotonin reuptake by the serotonin transporter, our analyses provide no evidence that susceptibility to AN is modified by 5-HTTLPR alone, nor in concert with as yet undetermined functional effects of the NETpPR polymorphism.
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Can venlafaxine block NET and SERT?
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We then performed the first reported investigation of epistasis between the SERT gene and norepinephrine transporter gene (SLC6A2, alias NET) in AN, as an earlier study suggested that atypical AN responds to the dual serotonin-norepinephrine reuptake inhibitor venlafaxine
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The animal gastrointestinal tract contains a complex community of microbes, whose composition ultimately reflects the co-evolution of microorganisms with their animal host. An analysis of 78,619 pyrosequencing reads generated from pygmy loris fecal DNA extracts was performed to help better understand the microbial diversity and functional capacity of the pygmy loris gut microbiome. The taxonomic analysis of the metagenomic reads indicated that pygmy loris fecal microbiomes were dominated by Bacteroidetes and Proteobacteria phyla. The hierarchical clustering of several gastrointestinal metagenomes demonstrated the similarities of the microbial community structures of pygmy loris and mouse gut systems despite their differences in functional capacity. The comparative analysis of function classification revealed that the metagenome of the pygmy loris was characterized by an overrepresentation of those sequences involved in aromatic compound metabolism compared with humans and other animals. The key enzymes related to the benzoate degradation pathway were identified based on the Kyoto Encyclopedia of Genes and Genomes pathway assignment. These results would contribute to the limited body of primate metagenome studies and provide a framework for comparative metagenomic analysis between human and non-human primates, as well as a comparative understanding of the evolution of humans and their microbiome. However, future studies on the metagenome sequencing of pygmy loris and other prosimians regarding the effects of age, genetics, and environment on the composition and activity of the metagenomes are required.
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List the three most abundant bacterial phyla present in mouse feces.
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The taxonomic analysis of the metagenomic reads indicated that pygmy loris fecal microbiomes were dominated by Bacteroidetes and Proteobacteria phyla.
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Liraglutide is a glucagon-like peptide-1 (GLP-1) analog marketed for the treatment of type 2 diabetes. Besides lowering blood glucose, liraglutide also reduces body weight. It is not fully understood how liraglutide induces weight loss or to what degree liraglutide acts directly in the brain. Here, we determined that liraglutide does not activate GLP-1-producing neurons in the hindbrain, and liraglutide-dependent body weight reduction in rats was independent of GLP-1 receptors (GLP-1Rs) in the vagus nerve, area postrema, and paraventricular nucleus. Peripheral injection of fluorescently labeled liraglutide in mice revealed the presence of the drug in the circumventricular organs. Moreover, labeled liraglutide bound neurons within the arcuate nucleus (ARC) and other discrete sites in the hypothalamus. GLP-1R was necessary for liraglutide uptake in the brain, as liraglutide binding was not seen in Glp1r(-/-) mice. In the ARC, liraglutide was internalized in neurons expressing proopiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART). Electrophysiological measurements of murine brain slices revealed that GLP-1 directly stimulates POMC/CART neurons and indirectly inhibits neurotransmission in neurons expressing neuropeptide Y (NPY) and agouti-related peptide (AgRP) via GABA-dependent signaling. Collectively, our findings indicate that the GLP-1R on POMC/CART-expressing ARC neurons likely mediates liraglutide-induced weight loss.
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Is liraglutide effective for weight reduction?
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Here, we determined that liraglutide does not activate GLP-1-producing neurons in the hindbrain, and liraglutide-dependent body weight reduction in rats was independent of GLP-1 receptors (GLP-1Rs) in the vagus nerve, area postrema, and paraventricular nucleus.
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Previously, we proposed a new model for understanding the Warburg effect in tumorigenesis and metastasis. In this model, the stromal fibroblasts would undergo aerobic glycolysis (a.k.a., the Warburg effect)--producing and secreting increased pyruvate/lactate that could then be used by adjacent epithelial cancer cells as "fuel" for the mitochondrial TCA cycle, oxidative phosphorylation, and ATP production. To test this model more directly, here we used a matched set of metabolically well-characterized immortalized fibroblasts that differ in a single gene. CL3 fibroblasts show a shift towards oxidative metabolism, and have an increased mitochondrial mass. In contrast, CL4 fibroblasts show a shift towards aerobic glycolysis, and have a reduced mitochondrial mass. We validated these differences in CL3 and CL4 fibroblasts by performing an unbiased proteomics analysis, showing the functional upregulation of 4 glycolytic enzymes, namely ENO1, ALDOA, LDHA and TPI1, in CL4 fibroblasts. Many of the proteins that were upregulated in CL4 fibroblasts, as seen by unbiased proteomics, were also transcriptionally upregulated in the stroma of human breast cancers, especially in the patients that were prone to metastasis. Importantly, when CL4 fibroblasts were co-injected with human breast cancer cells (MDA-MB-231) in a xenograft model, tumor growth was dramatically enhanced. CL4 fibroblasts induced a > 4-fold increase in tumor mass, and a near 8-fold increase in tumor volume, without any measurable increases in tumor angiogenesis. In parallel, CL3 and CL4 fibroblasts both failed to form tumors when they were injected alone, without epithelial cancer cells. Mechanistically, under co-culture conditions, CL4 glycolytic fibroblasts increased mitochondrial activity in adjacent breast cancer cells (relative to CL3 cells), consistent with the "Reverse Warburg Effect". Notably, Western blot analysis of CL4 fibroblasts revealed a significant reduction in caveolin-1 (Cav-1) protein levels. In human breast cancer patients, a loss of stromal Cav-1 is associated with an increased risk of early tumor recurrence, metastasis, tamoxifen-resistance, and poor clinical outcome. Thus, loss of stromal Cav-1 may be an effective marker for predicting the "Reverse Warburg Effect" in the stroma of human breast cancer patients. As such, CL4 fibroblasts are a new attractive model for mimicking the "glycolytic phenotype" of cancer-associated fibroblasts. Nutrients derived from glycolytic cancer associated fibroblasts could provide an escape mechanism to confer drug-resistance during anti-angiogenic therapy, by effectively reducing the dependence of cancer cells on a vascular blood supply.
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Which is the primary distinction between the Reverse Warburg effect and the conventional Warburg effect?
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Previously, we proposed a new model for understanding the Warburg effect in tumorigenesis and metastasis. In this model, the stromal fibroblasts would undergo aerobic glycolysis (a.k.a., the Warburg effect)--producing and secreting increased pyruvate/lactate that could then be used by adjacent epithelial cancer cells as "fuel" for the mitochondrial TCA cycle, oxidative phosphorylation, and ATP production.
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Frontotemporal dementia (FTD) is the second most frequent dementia, after Alzheimer's, in patients under the age of 65. It encompasses clinical entities characterized by behavioral, language, and executive control dysfunction. Neurofilament light chain (NfL) is a new, non-disease specific, widely studied biomarker indicative of axonal injury and degeneration. Various studies have previously explored the role of NfL in the diagnostic process, monitoring, and prognosis of dementia. The current systematic review and meta-analysis include all the available data concerning the role of NfL in frontotemporal dementia and its use as a potential biomarker in differentiating patients with FTD from (a) healthy individuals, (b) Alzheimer's dementia, (c) Dementia with Lewy bodies, (d) Motor Neuron disease, (e) Parkinsonian syndromes, and (f) psychiatric disorders. We also analyze the utility of NfL in distinguishing specific FTD subgroups. Neurofilament light chain has a potential role in differentiating patients with frontotemporal dementia from healthy controls, patients with Alzheimer's dementia, and psychiatric disorders. Higher NfL levels were also noted in patients with semantic primary progressive aphasia (PPA) when compared with behavioral FTD and non-fluent PPA patients. Further studies exploring the use of NfL in frontotemporal dementia are needed.
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Is neurofilament light marker for disease?
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Neurofilament light chain has a potential role in differentiating patients with frontotemporal dementia from healthy controls, patients with Alzheimer's dementia, and psychiatric disorders.
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Complex carbohydrates in the human cervix were studied histochemically using lectins conjugated to horseradish peroxidase and correlated procedures. Stratified squamous epithelium of the exocervix and columnar epithelium of the endocervix in some, but not all specimens showed staining for terminal alpha-N-acetyl-D-galactosamine, alpha-D-galactose, beta-D-galactose and alpha-L-fucose. The staining for alpha-N-acetylgalactosamine and alpha-galactose, the terminal sugars in blood group A and B antigens respectively, corresponded to a large extent with ABO blood type. One exception was the lack of staining for terminal alpha-N-acetylgalactosamine in endocervical secretions in three of nine blood type A patients. A second exception was the staining for terminal alpha-galactose in endocervical secretions in about half of blood type O and A specimens. The type and amount of glycoprotein formed by endocervical columnar cells differed according to location in superficial compared with deep portions of the glands and according to location at the junction with exocervix compared with the more internal regions. Staining of endothelial cells for blood group A and B antigens was confined to subjects of blood type A and B respectively, although three of nine type A specimens showed no lectin reactivity for group A antigen. Endothelial cells evidenced affinity for Ulex europeus I agglutinin demonstrative of fucose in all specimens. Mast cells disclosed lectin affinity consistent with the presence of terminal or internal mannose or N-acetylglucosamine residues. Two blood type O specimens were examined with conjugated lectins at the ultrastructural level. Secretory granules stained for content of terminal alpha-galactose, beta-galactose and fucose. These results support and concur with biochemical studies of complex carbohydrates in human cervical tissues. They reveal, in addition, the location of the blood group antigens in the human exocervix and endocervix and the marked heterogeneity among endocervical columnar cells in glycoprotein production.
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List the blood group antigens, associated with blood type
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staining for alpha-N-acetylgalactosamine and alpha-galactose, the terminal sugars in blood group A and B antigens respectively, corresponded to a large extent with ABO blood type. One
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Gaucher disease is an autosomal recessive disorder resulting from deficient activity of the lysosomal enzyme glucocerebrosidase (GBA, E.C.3.2.1.45). Three clinical forms of Gaucher disease have been described: type 1, nonneuronopathic; type 2, acute neuronopathic; and type 3, subacute neuronopathic (OMIM 230800, 230900, 231000). Over the past decade, recognition of a distinct, perinatal lethal form of Gaucher disease (PLGD) has led researchers and clinicians to evaluate Gaucher disease in the differential diagnosis of congenital ichthyosis and nonimmune hydrops fetalis. To date, more than 30 cases of PLGD have been genotyped and reported. It has been observed that homozygosity for recombinant GBA alleles, which are fundamentally null alleles, leads to early lethality, usually in utero or during the 1st few days of life, whereas genotypes involving a recombinant allele and a missense mutation may be less detrimental. Here, we report a case of Gaucher disease with prenatal onset and death within hours of birth, likely due to compound heterozygosity for the GBA Rec Nci I null allele and a R131C missense mutation. In view of the patient's severe clinical course, and based on reviews of other PLGD cases, we postulate that a missense mutation that abruptly disrupts the structure/function of GBA, in combination with a null allele, may result in early lethality in patients with PLGD. We also speculate that R131C is an extremely severe mutation that has occurred more than once in different populations and, in either the homozygous form or heterozygous with another severe mutation, will result in a poor prognosis.
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Which enzyme is deficient in Gaucher's disease?
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Gaucher disease is an autosomal recessive disorder resulting from deficient activity of the lysosomal enzyme glucocerebrosidase (GBA, E.C.3.2.1.45)
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Raxibacumab (ABthrax) is a human IgG1 monoclonal antibody against Bacillus anthracis protective antigen. HGS is currently providing stockpiles of the agent to the US government for use in the prevention and treatment of inhalation anthrax. As of May 2009, the candidate was undergoing review by the US Food and Drug Administration. The availability of bioterrorism countermeasures has become more important since the September 2001 anthrax attacks, and development of raxibacumab is a significant advance in this area.
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What is the mechanism of action of raxibacumab?
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The availability of bioterrorism countermeasures has become more important since the September 2001 anthrax attacks, and development of raxibacumab is a significant advance in this area.
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Necrobiosis lipoidica diabeticorum is an unusual dermatologic condition with a characteristic clinical appearance and a clear association with diabetes mellitus. There is currently no treatment that reverses the atrophic changes associated with this lesion. We have carried out a clinicopathologic study on 15 subjects and, in addition, have reviewed 10 further biopsy specimens of necrobiosis lipoidica diabeticorum. We found a frequent association of necrobiosis lipoidica diabeticorum with other chronic complications of diabetes mellitus, including limited joint mobility. It is possible that nonenzymatic glucosylation or other changes in collagen may be important in the etiology of necrobiosis lipoidica diabeticorum and the limited joint mobility. We confirmed that cutaneous anesthesia is usually present in the necrobiosis lipoidica diabeticorum lesions. With the use of an antibody to S100 protein and an immunohistochemical method, there was an apparent decreased number of nerves in the skin lesions. We suggest that sensory loss results from local destruction of cutaneous nerves by the inflammatory process. Finally, in six elliptical biopsies extending into clinically normal skin, we demonstrated that the inflammatory infiltrate of necrobiosis lipoidica diabeticorum extended from the lesion into apparently normal skin surrounding clinically active lesions. Thus, intradermal steroids might be administered to perilesional areas surrounding active lesions in the hope of halting progression.
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Which disease the skin condition Necrobiosis lipoidica diabeticorum is associated to?
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Necrobiosis lipoidica diabeticorum is an unusual dermatologic condition with a characteristic clinical appearance and a clear association with diabetes mellitus.
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The genomes of vertebrates, flies, and nematodes contain highly conserved noncoding elements (CNEs). CNEs cluster around genes that regulate development, and where tested, they can act as transcriptional enhancers. Within an animal group CNEs are the most conserved sequences but between groups they are normally diverged beyond recognition. Alternative CNEs are, however, associated with an overlapping set of genes that control development in all animals. Here, we discuss the evidence that CNEs are part of the core gene regulatory networks (GRNs) that specify alternative animal body plans. The major animal groups arose >550 million years ago. We propose that the cis-regulatory inputs identified by CNEs arose during the "re-wiring" of regulatory interactions that occurred during early animal evolution. Consequently, different animal groups, with different core GRNs, contain alternative sets of CNEs. Due to the subsequent stability of animal body plans, these core regulatory sequences have been evolving in parallel under strong purifying selection in different animal groups.
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Are there Conserved Noncoding Elements (CNEs) in invertebrate genomes?
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The genomes of vertebrates, flies, and nematodes contain highly conserved noncoding elements (CNEs)
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MicroRNAs (miRNAs) are a class of non-coding small RNAs representing one of the most exciting areas of modern medical science. miRNAs modulate a large and complex regulatory network of gene expression of the majority of the protein-coding genes. Currently, evidences suggest that miRNAs play a crucial role in the pathogenesis of heart failure. Some miRNAs as miR-1, miR-133 and miR-208a are highly expressed in the heart and strongly associated with the development of cardiac hypertrophy. Recent data indicate that these miRNAs as well as miR-206 change their expression quickly in response to physical activity. The differential regulation of miRNAs in response to exercise suggests a potential value of circulating miRNAs (c-miRNAs) as biomarkers of physiological mediators of the cardiovascular adaptation induced by exercise. Likewise, serum levels of c-miRNAs such as miR-423-5p have been evaluated as potential biomarkers in the diagnosis and prognosis of heart failure. On the other hand, the manipulation of miRNAs levels using techniques such as 'miR mimics' and 'antagomiRs' is becoming evident the enormous potential of miRNAs as promising therapeutic strategies in heart failure.
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Which microRNAs are involved in exercise adaptation?
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Some miRNAs as miR-1, miR-133 and miR-208a are highly expressed in the heart and strongly associated with the development of cardiac hypertrophy. Recent data indicate that these miRNAs as well as miR-206 change their expression quickly in response to physical activity.
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Gfi1b and Gfi1 are 37- and 55-kDa transcriptional repressors that share common features such as a 20-amino acid (aa) N-terminal SNAG domain, a nonconserved intermediary domain, and 6 highly conserved C-terminal zinc fingers. Both gene loci are under autoregulatory and cross-regulatory feedback control. We have generated a reporter mouse strain by inserting the cDNA for green fluorescent protein (GFP) into the Gfi1b gene locus which allowed us to follow Gfi1b expression during hematopoiesis and lymphopoiesis by measuring green fluorescence. We found highly dynamic expression patterns of Gfi1b in erythroid cells, megakaryocytes, and their progenitor cells (MEPS) where Gfi1 is not detected. Vice versa, Gfi1b could not be found in granulocytes, activated macrophages, or their granulomonocytic precursors (GMPs) or in mature naive or activated lymphocytes where Gfi1 is expressed, suggesting a complementary regulation of both loci during hematopoiesis. However, Gfi1b was found to be up-regulated in early stages of B-cell and in a subset of early T-cell development, where Gfi1 is also present, suggesting that cross-regulation of both loci exists but is cell-type specific.
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Is Growth factor independence 1b (GFI1B) important for hematopoiesis?
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We found highly dynamic expression patterns of Gfi1b in erythroid cells, megakaryocytes, and their progenitor cells (MEPS) where Gfi1 is not detected. Vice versa, Gfi1b could not be found in granulocytes, activated macrophages, or their granulomonocytic precursors (GMPs) or in mature naive or activated lymphocytes where Gfi1 is expressed, suggesting a complementary regulation of both loci during hematopoiesis
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Despite the fact that G protein-coupled receptors (GPCRs) mediate numerous physiological processes and represent targets for therapeutics for a vast array of diseases, their role in tumor biology is under appreciated. Protease-activated receptors (PARs) form a family which belongs to GPCR class A. PAR1&2 emerge with a central role in epithelial malignancies. Although the part of PAR1&2 in cancer is on the rise, their underlying signaling events are poorly understood. We review hereby past, present, and future cancer-associated PAR biology. Mainly, their role in physiological (placenta-cytotophobalst) and patho-physiological invasion processes. The identification and characterization of signal pleckstrin homology (PH)-domain-binding motifs established critical sites for breast cancer growth in PAR1&2. Among the proteins found to harbor important PH-domains and are involved in PAR biology are Akt/PKB as also Etk/Bmx and Vav3. A point mutation in PAR2, H349A, but not R352A, abrogated PH-protein association and is sufficient to markedly reduce PAR2-instigated breast tumor growth in vivo as also placental extravillous trophoblast (EVT) invasion in vitro is markedly reduced. Similarly, the PAR1 mutant hPar1-7A, which is unable to bind PH-domain, inhibits mammary tumors and EVT invasion, endowing these motifs with physiological significance and underscoring the importance of these previously unknown PAR1 and PAR2 PH-domain-binding motifs in both pathological and physiological invasion processes.
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PH motifs in which genes endow breast cancer growth?
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The identification and characterization of signal pleckstrin homology (PH)-domain-binding motifs established critical sites for breast cancer growth in PAR1&2.
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Hypertrophic Cardiomyopathy (HCM) is a common primary cardiac disorder defined by a hypertrophied left ventricle, is one of the main causes of sudden death in young athletes, and has been associated with mutations in most sarcomeric proteins (tropomyosin, troponin T and I, and actin, etc.). Many of these mutations appear to affect the functional properties of cardiac troponin C (cTnC), i.e., by increasing the Ca(2+)-sensitivity of contraction, a hallmark of HCM, yet surprisingly, prior to this report, cTnC had not been classified as a HCM-susceptibility gene. In this study, we show that mutations occurring in the human cTnC (HcTnC) gene (TNNC1) have the same prevalence (~0.4%) as well established HCM-susceptibility genes that encode other sarcomeric proteins. Comprehensive open reading frame/splice site mutation analysis of TNNC1 performed on 1025 unrelated HCM patients enrolled over the last 10 years revealed novel missense mutations in TNNC1: A8V, C84Y, E134D, and D145E. Functional studies with these recombinant HcTnC HCM mutations showed increased Ca(2+) sensitivity of force development (A8V, C84Y and D145E) and force recovery (A8V and D145E). These results are consistent with the HCM functional phenotypes seen with other sarcomeric-HCM mutations (E134D showed no changes in these parameters). This is the largest cohort analysis of TNNC1 in HCM that details the discovery of at least three novel HCM-associated mutations and more strongly links TNNC1 to HCM along with functional evidence that supports a central role for its involvement in the disease. This study may help to further define TNNC1 as an HCM-susceptibility gene, a classification that has already been established for the other members of the troponin complex.
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which mutations of troponin C gene have been found to cause hypertrophic cardiomyopathy?
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Comprehensive open reading frame/splice site mutation analysis of TNNC1 performed on 1025 unrelated HCM patients enrolled over the last 10 years revealed novel missense mutations in TNNC1: A8V, C84Y, E134D, and D145E.
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Bednar tumor is a rare pigmented variation of dermatofibrosarcoma protuberans, present in 1 to 5% of all patients with dermatofibrosarcoma protuberans. No significant clinicopathologic differences exist between Bednar tumor and conventional dermatofibrosarcoma protuberans apart from the presence of scattered nonneoplastic pigmented dendritic cells in the former. Although most dermatofibrosarcoma protuberans occur in adults, they may be rarely present at birth. Fanconi anemia is a genetically heterogeneous chromosomal instability syndrome, characterized by multiple congenital anomalies, progressive bone marrow failure, and a predisposition to malignancy. We describe here a patient with Fanconi anemia who had a congenital Bednar tumor. To our knowledge, this is the first such patient described with both dermatofibrosarcoma protuberans and Fanconi anemia.
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Is Fanconi anemia presented as a genetically and clinically heterogeneous disease entity?
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Fanconi anemia is a genetically heterogeneous chromosomal instability syndrome, characterized by multiple congenital anomalies, progressive bone marrow failure, and a predisposition to malignancy.
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Analysis by molecular hybridization of the RNAs transcribed by a cell-free fraction from avocado infected with avocado sunblotch viroid (ASBV) demonstrated the presence of newly synthesized viroid-specific sequences, most of which were of the same polarity as the mature infectious viroid RNA. Treatment of the cell-free fraction with DNase reduced the total synthesis of RNA considerably, but it did not influence that of the ASBV-specific RNAs, indicating that the latter were transcribed on an RNA template. Inhibition studies with alpha-amanitin showed that the synthesis of ASBV-specific RNAs was not affected by concentrations of 1 and 200 micrograms/ml of the drug, which typically inhibit RNA polymerase II and III, respectively, from most animal and plant systems. These results suggest that either RNA polymerase I or an unidentified RNA polymerase activity resistant to alpha-amanitin, acting on an RNA template, plays a role in the replication of ASBV, whereas for the rest of the viroids studied so far it appears that RNA polymerase II is involved. Analysis by polycrylamide gel electrophoresis under partially and fully denaturing conditions of the ASBV-specific RNAs synthesized in vitro showed that they contain unit and longer than unit length viroid strands, probably associated in complexes with single- and double-stranded regions. The structural properties of these complexes are similar to those of the RNAs accumulating in vivo in viroid-infected tissues, which are the postulated replicative intermediates of the rolling-circle mechanism proposed for viroid synthesis.
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Which RNA polymerase is used for the replication of viroids?
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Inhibition studies with alpha-amanitin showed that the synthesis of ASBV-specific RNAs was not affected by concentrations of 1 and 200 micrograms/ml of the drug, which typically inhibit RNA polymerase II and III, respectively, from most animal and plant systems. These results suggest that either RNA polymerase I or an unidentified RNA polymerase activity resistant to alpha-amanitin, acting on an RNA template, plays a role in the replication of ASBV, whereas for the rest of the viroids studied so far it appears that RNA polymerase II is involved.
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During gene transcription, the RNA polymerase (Pol) active center can catalyze RNA cleavage. This intrinsic cleavage activity is strong for Pol I and Pol III but very weak for Pol II. The reason for this difference is unclear because the active centers of the polymerases are virtually identical. Here we show that Pol II gains strong cleavage activity when the C-terminal zinc ribbon domain (C-ribbon) of subunit Rpb9 is replaced by its counterpart from the Pol III subunit C11. X-ray analysis shows that the C-ribbon has detached from its site on the Pol II surface and is mobile. Mutagenesis indicates that the C-ribbon transiently inserts into the Pol II pore to complement the active center. This mechanism is also used by transcription factor IIS, a factor that can bind Pol II and induce strong RNA cleavage. Together with published data, our results indicate that Pol I and Pol III contain catalytic C-ribbons that complement the active center, whereas Pol II contains a non-catalytic C-ribbon that is immobilized on the enzyme surface. Evolution of the Pol II system may have rendered mRNA transcript cleavage controllable by the dissociable factor transcription factor IIS to enable promoter-proximal gene regulation and elaborate 3'-processing and transcription termination.
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Which RNA polymerase II subunit carries RNA cleavage activity?
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This mechanism is also used by transcription factor IIS, a factor that can bind Pol II and induce strong RNA cleavage.
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Elevated numbers of blood and tissue eosinophils are present in allergic diseases and experimental evidence suggests that eosinophils play an important pathogenic role in these conditions. Regulation of eosinophil maturation, recruitment, and survival is under the control of a small group of factors, including interleukin-5 (IL-5). Given the probable importance of eosinophils to allergy and other associated disorders, IL-5 has been proposed as a potential molecular target in the treatment of these diseases. IL-5 antagonist therapies in current development include two monoclonal anti-IL-5 antibodies (mepolizumab, reslizumab), a monoclonal antibody directed at the IL-5 receptor (benralizumab), and anti-sense oligonucleotide therapy (TPI ASM8). Anti-IL5 antibody therapy has been the most extensively studied of these agents, and trials have been performed in patients with bronchial asthma, nasal polyposis, atopic dermatitis, eosinophilic esophagitis, hypereosinophilic syndrome, and Churg-Strauss syndrome. In studies of asthmatics, anti-IL-5 showed minimal efficacy in patients with moderate, controlled asthma. In patients with severe, refractory asthma associated with eosinophilia, however, clinical trials have demonstrated significant reductions in asthma exacerbations. Clinical studies in other disorders, particularly eosinophilic esophagitis and hypereosinophilic syndrome, have also shown significant improvements in blood and/or tissue eosinophilia and variable alterations in clinical disease activity. Strategies aimed at the inhibition of IL-5 may hold great promise in the treatment of eosinophilic diseases.
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What do mepolizumab and reslizumab have in common?
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IL-5 antagonist therapies in current development include two monoclonal anti-IL-5 antibodies (mepolizumab, reslizumab), a monoclonal antibody directed at the IL-5 receptor (benralizumab), and anti-sense oligonucleotide therapy (TPI ASM8).
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Over the past 15 years we have treated 526 patients with severe hyperkinetic movement disorders with tetrabenazine (TBZ), a monoamine-depleting and a dopamine-receptor-blocking drug. We report here the results in 400 patients with adequate follow-up. The response was rated on a scale of 1 to 5 (1 = marked improvement, 4 = no response, 5 = worsening) and was assessed initially and at the last clinic visit. The average duration of TBZ treatment was 28.9 months (+/- 31.1; range, 0.25 to 180 months). The global response rating of 1 (marked improvement) was recorded in 89.2% of 93 patients with tardive stereotypy, 83.3% of 12 with myoclonus, 82.8% of 29 with Huntington's disease, 80.5% of 82 with tardive dystonia, 79.3% of 29 with other movement disorders, 62.9% of 108 with idiopathic dystonia, and in 57.4% of 47 with Tourette's syndrome. The most common side effects included drowsiness (36.5%), parkinsonism (28.5%), depression (15.0%), insomnia (11.0%), nervousness or anxiety (10.3%), and akathisia (9.5%). The side effects were controlled with reduction in the dosage. TBZ is an effective and safe drug for the treatment of a variety of hyperkinetic movement disorders. In contrast to typical neuroleptics, TBZ has not been demonstrated to cause tardive dyskinesia.
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What is the percentage of responders to tetrabenazine treatment for dystonia in children?
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The global response rating of 1 (marked improvement) was recorded in 89.2% of 93 patients with tardive stereotypy, 83.3% of 12 with myoclonus, 82.8% of 29 with Huntington's disease, 80.5% of 82 with tardive dystonia, 79.3% of 29 with other movement disorders, 62.9% of 108 with idiopathic dystonia
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The most common cause of sudden cardiac death in individuals aged less than 35 years, including competitive athletes, is the inherited disorder hypertrophic cardiomyopathy (HCM). Until recently, no therapeutic intervention had been identified to prevent sudden death in HCM. This case report highlights the role of the implantable cardioverter defibrillator (ICD) in preventing sudden death in patients with HCM. The report highlights the importance of risk stratification in patients with HCM in order to identify those individuals who would most likely benefit from ICD therapy. The ICD implantation is now the treatment of choice in preventing sudden death in selected (highest risk) populations with HCM. In the future, understanding the molecular basis of sudden death in HCM may identify potential new gene-based therapeutic strategies.
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Which is the most common cause of sudden cardiac death in young athletes?
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The most common cause of sudden cardiac death in individuals aged less than 35 years, including competitive athletes, is the inherited disorder hypertrophic cardiomyopathy (HCM).
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Five hundred members belonging to the Bania community of Punjab were screened for erythrocytic glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. The incidence of enzyme deficiency in males was 2.84 per cent and in females 2.75 per cent, with an overall incidence of 2.80 per cent. No correlation between age and G-6-PD deficiency was found. The mean values for haemoglobin and haematocrit did not differ significantly in the normal and deficient subjects. Study of the deficiency pattern amongst family members of the enzyme deficient subjects confirmed the X-linked inheritance of G-6-PD deficiency.
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What is the inheritance of the glucose-6-phosphate dehydrogenase (G6PD) deficiency?
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Study of the deficiency pattern amongst family members of the enzyme deficient subjects confirmed the X-linked inheritance of G-6-PD deficiency.
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In patients undergoing peritoneal dialysis (PD), chronic exposure to nonphysiologic PD fluids elicits low-grade peritoneal inflammation, leading to fibrosis and angiogenesis. Phenotype conversion of mesothelial cells into myofibroblasts, the so-called mesothelial-to-mesenchymal transition (MMT), significantly contributes to the peritoneal dysfunction related to PD. A number of factors have been described to induce MMT in vitro and in vivo, of which TGF-β1 is probably the most important. The vasoconstrictor peptide endothelin-1 (ET-1) is a transcriptional target of TGF-β1 and mediates excessive scarring and fibrosis in several tissues. This work studied the contribution of ET-1 to the development of peritoneal damage and failure in a mouse model of PD. ET-1 and its receptors were expressed in the peritoneal membrane and upregulated on PD fluid exposure. Administration of an ET receptor antagonist, either bosentan or macitentan, markedly attenuated PD-induced MMT, fibrosis, angiogenesis, and peritoneal functional decline. Adenovirus-mediated overexpression of ET-1 induced MMT in human mesothelial cells in vitro and promoted the early cellular events associated with peritoneal dysfunction in vivo. Notably, TGF-β1-blocking peptides prevented these actions of ET-1. Furthermore, a positive reciprocal relationship was observed between ET-1 expression and TGF-β1 expression in human mesothelial cells. These results strongly support a role for an ET-1/TGF-β1 axis as an inducer of MMT and subsequent peritoneal damage and fibrosis, and they highlight ET-1 as a potential therapeutic target in the treatment of PD-associated dysfunction.
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Is macitentan an ET agonist?
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Administration of an ET receptor antagonist, either bosentan or macitentan, markedly attenuated PD-induced MMT, fibrosis, angiogenesis, and peritoneal functional decline.
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The Library of Integrated Cellular Signatures (LINCS) project provides comprehensive transcriptome profiling of human cell lines before and after chemical and genetic perturbations. Its L1000 platform utilizes 978 landmark genes to infer the transcript levels of 14,292 genes computationally. Here we conducted the L1000 data quality control analysis by using MCF7, PC3, and A375 cell lines as representative examples. Before perturbations, a promising 80% correlation in transcriptome was observed between L1000- and Affymetrix HU133A-platforms. After library-based shRNA perturbations, a moderate 30% of differentially expressed genes overlapped between any two selected controls viral vectors using the L1000 platform. The mitogen-activated protein kinase, vascular endothelial growth factor, and T-cell receptor pathways were identified as the most significantly shared pathways between chemical and genetic perturbations in cancer cells. In conclusion, L1000 platform is reliable in assessing transcriptome before perturbation. Its response to perturbagens needs to be interpreted with caution. A quality control analysis pipeline of L1000 is recommended before addressing biological questions.
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What is the purpose of the LINCS Project?
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The Library of Integrated Cellular Signatures (LINCS) project provides comprehensive transcriptome profiling of human cell lines before and after chemical and genetic perturbations.
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Candidate-gene association studies in rheumatoid arthritis (RA) have lead to encouraging yet apparently inconsistent results. One explanation for the inconsistency is insufficient power to detect modest effects in the context of a low prior probability of a true effect. To overcome this limitation, we selected alleles with an increased probability of a disease association, on the basis of a review of the literature on RA and other autoimmune diseases, and tested them for association with RA susceptibility in a sample collection powered to detect modest genetic effects. We tested 17 alleles from 14 genes in 2,370 RA cases and 1,757 controls from the North American Rheumatoid Arthritis Consortium (NARAC) and the Swedish Epidemiological Investigation of Rheumatoid Arthritis (EIRA) collections. We found strong evidence of an association of PTPN22 with the development of anti-citrulline antibody-positive RA (odds ratio [OR] 1.49; P=.00002), using previously untested EIRA samples. We provide support for an association of CTLA4 (CT60 allele, OR 1.23; P=.001) and PADI4 (PADI4_94, OR 1.24; P=.001) with the development of RA, but only in the NARAC cohort. The CTLA4 association is stronger in patients with RA from both cohorts who are seropositive for anti-citrulline antibodies (P=.0006). Exploration of our data set with clinically relevant subsets of RA reveals that PTPN22 is associated with an earlier age at disease onset (P=.004) and that PTPN22 has a stronger effect in males than in females (P=.03). A meta-analysis failed to demonstrate an association of the remaining alleles with RA susceptibility, suggesting that the previously published associations may represent false-positive results. Given the strong statistical power to replicate a true-positive association in this study, our results provide support for PTPN22, CTLA4, and PADI4 as RA susceptibility genes and demonstrate novel associations with clinically relevant subsets of RA.
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Is the PTPN22 gene a biomarker for Rheumatoid Arthritis?
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Given the strong statistical power to replicate a true-positive association in this study, our results provide support for PTPN22, CTLA4, and PADI4 as RA susceptibility genes and demonstrate novel associations with clinically relevant subsets of RA
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The antifungal compound 2,4-diacetylphloroglucinol-producing bacterium, Pseudomonas fluorescens strain LRB3W1, inhibits the growth of Fusarium oxysporum f. sp. lycopersici, and controls Fusarium wilt of tomato caused by F. oxysporum f. sp. lycopersici. On the other hand, Serratia marcescens strain B2, which produces cell wall-degrading enzyme chitinases, did not inhibit fungal growth and the suppressive effect of strain B2 against tomato Fusarium wilt was less than that of strain LRB3W1. Combined inoculation of strain LRB3W1 with strain B2 was more effective than treatment with strain LRB3W1 alone. When 2,4-diacetylphloroglucinol and the chitinolytic enzymes were applied in combination, a synergistic inhibitory effect against the pathogen was observed. It was possible that bacteria which produce cell wall-degrading enzymes enhanced the biocontrol effect of the antibiotic-producing bacterium against tomato Fusarium wilt.
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Fusarium oxysporum f. sp lycopersici. is a plant pathogen in plants producing what common food?
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Fusarium wilt of tomato caused by F. oxysporum f. sp. lycopersici.
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Abnormal development and fetal loss during postimplantation period are concerns for production of nuclear transferred animals. Aberrant DNA methylation is one of the reasons for poor survival of cloned animals. In mammalian genome DNA, CpG islands are preferentially located at the start of transcription of housekeeping genes and are associated with tissue-specific genes. The correct and consecutive mechanisms of DNA methylation in the CpG islands are necessary for selective gene expressions that determine the properties of individual cells, tissues, and organs. In this study, we investigated the methylation status of the CpG islands of the bovine Leptin and POU5F1 genes in fetal and placental tissues from fetuses produced by artificial insemination (AI) and nuclear transfer (NT) at days 48 and 59 of pregnancy. Altered DNA methylation was observed in the normal and cloned fetal, placental, and endometrial tissues using bisulfite sequencing and pyrosequencing. Different tissue-specific methylated regions in the bovine Leptin and POU5F1 genes show a variable methylation status in NT fetuses compared to AI control.
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Are CpG islands located close to housekeeping genes?
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CpG islands are preferentially located at the start of transcription of housekeeping genes and are associated with tissue-specific genes
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DNA repair has an essential role in protecting the genome from damage by endogenous and environmental agents. Polymorphisms in DNA repair genes and differences in repair capacity between individuals have been widely documented. For colorectal cancer, the loss of mismatch repair gene activity is a key genetic determinant. Nucleotide excision repair (NER), recombination repair (RR) and base excision repair (BER) pathways have critical roles in protection against other cancers, and we wished to investigate their role in colorectal cancer. We have compared the frequency of polymorphisms in the NER genes, XPD, XPF, XPG, ERCC1; in the BER gene, XRCC1; and in the RR gene, XRCC3; in colorectal cancer patients and in a control group. No significant associations were found for any of the NER gene polymorphisms or for the XRCC1 polymorphism. The C allele (position 18067) of the XRCC3 gene was weakly but significantly associated with colorectal cancer (odds ratio 1.52, 95% confidence interval 1.04-2.22, P=0.03). For all patients who were heterozygous for any of the repair genes studied, tumour tissue was investigated for loss of heterozygosity (LOH). Only one example of LOH was found for all the genes examined. From the association and LOH data, we conclude that these genes do not have an important role in protection against colorectal carcinogenesis.
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Are defects in recombination repair involved in carcinogenesis?
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olymorphisms in DNA repair genes and differences in repair capacity between individuals have been widely documented. For colorectal cancer, the loss of mismatch repair gene activity is a key genetic determinant. Nucleotide excision repair (NER), recombination repair (RR) and base excision repair (BER) pathways have critical roles in protection against other cancers, and we wished to investigate their role in colorectal cancer.
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FgfR3 (P244R) mutant mice show premature fusion of facial sutures, premaxillary and/or zygomatic sutures, but rarely the coronal suture. The mice also lack the typical limb phenotype. On the other hand, the mutant mice display maxillary retrusion in association with a shortening of the anterior cranial base and a premature closure of intersphenoidal and spheno-occipital synchondroses, resembling human midface hypoplasia. In addition, sensorineural hearing loss is detected in all FgfR3 (P244R) mutant mice as in the majority of Muenke syndrome patients. It is caused by a defect in the mechanism of cell fate determination in the organ of Corti. The mice also express phenotypes that have not been previously described in humans, such as reduced cortical bone thickness, hypoplastic trabecular bone, and defective temporomandibular joint structure. Therefore, the FgfR3 (P244R) mouse provides an excellent opportunity to study disease mechanisms of some classical phenotypes of Muenke syndrome and to test novel therapeutic strategies. The mouse model can also be further explored to discover previously unreported yet potentially significant phenotypes of Muenke syndrome.
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Is there an association between Muenke Syndrome and FGFR3 gene mutation?
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In addition, sensorineural hearing loss is detected in all FgfR3 (P244R) mutant mice as in the majority of Muenke syndrome patients.
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Melanoma is an aggressive form of skin cancer that causes the greatest number of skin cancer-related deaths worldwide. In its early stages malignant melanoma can be cured by surgical resection, but once it has progressed to the metastatic stage it is extremely difficult to treat and does not respond to current therapies. A majority of cutaneous melanomas show activating mutations in the NRAS or BRAF proto-oncogenes, components of the Ras-Raf-Mek-Erk (MAPK) signal transduction pathway. The discovery of activating BRAF mutations in ∼50% of all melanomas has proved to be a turning point in the therapeutic management of the disseminated disease. This review summarizes the critical role of BRAF in melanoma pathophysiology, the clinical and pathological determinants of BRAF mutation status and finally addresses the current state of the art of BRAF inhibitors. We further outline the most recent findings on the mechanisms that underlie intrinsic and acquired BRAF inhibitor resistance and describe ongoing preclinical and clinical studies designed to delay or abrogate the onset of therapeutic escape.
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Are BRAF mutations common in melanoma?
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A majority of cutaneous melanomas show activating mutations in the NRAS or BRAF proto-oncogenes, components of the Ras-Raf-Mek-Erk (MAPK) signal transduction pathway. The discovery of activating BRAF mutations in ∼50% of all melanomas has proved to be a turning point in the therapeutic management of the disseminated disease. This review summarizes the critical role of BRAF in melanoma pathophysiology, the clinical and pathological determinants of BRAF mutation status and finally addresses the current state of the art of BRAF inhibitors.
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Wernicke's encephalopathy may be fatal if untreated. Because Wernicke's encephalopathy is suspected to be underdiagnosed in children, the authors wished to assess the frequency of overlooked diagnosis and to establish pertinent findings that could lead to early identification of pediatric Wernicke's encephalopathy. The authors performed multiple literature searches seeking pediatric patients with Wernicke's encephalopathy (age = 20 years or younger). A total of 30 patients was found, and the authors added a new patient. Each case report had its clinical, radiologic, and laboratory data, diagnostic method, and outcome analyzed. Of 31 patients, 16 were female and 15 male; the median age +/- S.D. was 11 +/- 6.5 years. The most frequent underlying disorder was malignancy in 11. Thirteen patients died undiagnosed, 16 recovered with thiamine therapy (eight with sequelae), and two died of infection soon after thiamine replacement was initiated. Only six presented with the Wernicke's encephalopathy clinical triad (mental status changes, ocular signs, and ataxia) at neurologic onset; nine eventually demonstrated this triad. The high rate of patients diagnosed only at postmortem examination (41.9%) confirms that Wernicke's encephalopathy is underdiagnosed in children. Thiamine therapy is warranted if any component of the Wernicke's encephalopathy triad is present in an appropriate clinical setting.
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Name triad of Wernicke encephalopathy.
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Only six presented with the Wernicke's encephalopathy clinical triad (mental status changes, ocular signs, and ataxia) at neurologic onset; nine eventually demonstrated this triad.
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Viral quasispecies population dynamics between monocytes and T-lymphocytes were analyzed in patients after highly active antiretroviral therapy (HAART) interruption, during a follow-up of 3-6 months. V3 env region underwent ultra-deep pyrosequencing. Co-receptor usage prediction was performed by Position Specific Score Matrix Analysis. Phylogenetic trees were constructed to evaluate the relationships between the variants. Gene flow was also investigated. Even though at the moment of therapy interruption monocyte-derived HIV-1 genomes presented higher genetic heterogeneity than that of T-lymphocytes, at subsequent times, this difference in genetic heterogeneity disappeared, due to different waves of expansion and reduction of quasispecies variability associated with monocytes and T-lymphocytes. Phylogenetic analysis and gene flow evaluation supported the hypothesis of extensive interchange of variants between cellular compartments of the infection. A spread of proviral X4 lineages hidden in monocytes to T cells was observed, but this was not associated with an overall shift towards CXCR4 using variants during the observation period.
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Is there a phylogenetic analysis for HIV?
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Phylogenetic trees were constructed to evaluate the relationships between the variants
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Overcoming antigenic variation is one of the major challenges in the development of an effective vaccine against Plasmodium falciparum, a causative agent of human malaria. Inclusion of multiple Ag variants in subunit vaccine candidates is one strategy that has aimed to overcome this problem for the leading blood-stage malaria vaccine targets, that is, merozoite surface protein 1 (MSP1) and apical membrane Ag 1 (AMA1). However, previous studies, utilizing malaria Ags, have concluded that inclusion of multiple allelic variants, encoding altered peptide ligands, in such a vaccine may be detrimental to both the priming and in vivo restimulation of Ag-experienced T cells. In this study, we analyze the T cell responses to two alleles of MSP1 and AMA1 induced by vaccination of malaria-naive adult volunteers with bivalent viral-vectored vaccine candidates. We show a significant bias to the 3D7/MAD20 allele compared with the Wellcome allele for the 33 kDa region of MSP1, but not for the 19 kDa fragment or the AMA1 Ag. Although this bias could be caused by "immune interference" at priming, the data do not support a significant role for "immune antagonism" during memory T cell restimulation, despite observation of the latter at a minimal epitope level in vitro. A lack of class I HLA epitopes in the Wellcome allele that are recognized by vaccinated volunteers may in fact contribute to the observed bias. We also show that controlled infection with 3D7 strain P. falciparum parasites neither boosts existing 3D7-specific T cell responses nor appears to "immune divert" cellular responses toward the Wellcome allele.
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Which is the causative agent of malaria?
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Overcoming antigenic variation is one of the major challenges in the development of an effective vaccine against Plasmodium falciparum, a causative agent of human malaria.
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HIC-1 is a gene that is hypermethylated in cancer, and commonly downregulated in human breast cancer. However, the precise mechanisms and molecular pathways regulated by HIC-1 remain unclear. We assessed HIC-1 expression on a tissue microarray containing 80 cases of breast cancer. We also analyzed its biological function by restoring HIC-1 expression using 5-aza-2' deoxycytidine (5-CdR) and small-activating RNAs for the reversal of HIC-1 tumor suppressive effects on MCF-7 and MDA-MB-231 cell lines. An Agilent Q44h global expressing microarray was probed after restoring the expression of HIC-1. Data demonstrated that HIC-1 expression was reduced significantly in breast cancer tissues. HIC-1 immunohistochemistry resulted in mean staining scores in cancer tissue and normal ductal epithelia of 3.54 and 8.2, respectively (p<0.01). 5-CdR partially reversed HIC-1 expression, and modulated cell growth and apoptosis. dsHIC1-2998, an saRNA, showed activating efficacy in breast cancer cells. A group of differentially expressed genes were characterized by cDNA microarray. Upon saRNA treatment, genes upregulated included those involved in immune activation, cell cycle interference, the induction of apoptosis, anti-metastasis, and cell differentiation. Downregulated genes included oncogenes and those that play roles in cell invasion, cell growth, and cell division. Our findings may provide valuable resources not only for gene functional studies, but also for potential clinical applications to develop novel drug targets.
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List 3 diseases for which saRNAs have been evaluated as a potential treatment.
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Upon saRNA treatment, genes upregulated included those involved in immune activation, cell cycle interference, the induction of apoptosis, anti-metastasis, and cell differentiation. Downregulated genes included oncogenes and those that play roles in cell invasion, cell growth, and cell division.
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Coronavirus disease 2019 (COVID-19) is an emerging infectious disease that has resulted in a global pandemic and is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Zoonotic diseases are infections that are transmitted from animals to humans. COVID-19 caused by SARS-CoV-2 most likely originated in bats and transmitted to humans through a possible intermediate host. Based on published research so far, pangolins are considered the most likely intermediate hosts. Further studies are needed on different wild animal species, including pangolins that are sold at the same wet market or similar wet markets before concluding pangolins as definitive intermediate hosts. SARS-CoV-2 is capable of reverse zoonosis as well. Additional research is needed to understand the pathogenicity of the virus, especially in companion animals, modes of transmission, incubation period, contagious period, and zoonotic potential. Interdisciplinary one health approach handles these mosaic issues of emerging threats by integrating professionals from multiple disciplines like human medicine, veterinary medicine, environmental health, and social sciences. Given that the future outbreak of zoonotic diseases is inevitable, importance must be given for swift identification of the pathogen, source, and transmission methods. Countries should invest in identifying the hot spots for the origin of zoonotic diseases, enhance diagnostic capabilities, and rapid containment measures at local, regional, and national levels. The threat posed by emerging infectious diseases in modern-days also needs combined efforts internationally where a single discipline or nation cannot handle the burden alone.
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Covid-19 is though to have arisen from what species?
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COVID-19 caused by SARS-CoV-2 most likely originated in bats and transmitted to humans through a possible intermediate host.
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The activity of TLC G-65 (a liposomal gentamicin preparation), alone and in combination with rifapentine, clarithromycin, clofazimine and ethambutol, was evaluated in the beige mouse (C57BL/6J--bgj/bgj) model of disseminated Mycobacterium avium infection. TLC G-65 was found to be more active than amikacin. The combination of rifapentine and TLC G-65 was more active than either agent alone. The activity of clarithromycin in combination with TLC G-65 was similar to that of either agent alone. Clofazimine improved the activity of TLC G-65 with respect to the spleen, while ethambutol improved the activity with respect to the liver. Clofazimine and ethambutol enhanced the activity of TLC G-65 against bacteria in the lungs. TLC G-65 in combination with rifapentine appears to be an attractive regimen for the treatment of infections caused by bacteria in the M. avium complex.
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What is the suggested therapy for Mycobacterium avium infection?
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The activity of TLC G-65 (a liposomal gentamicin preparation), alone and in combination with rifapentine, clarithromycin, clofazimine and ethambutol, was evaluated in the beige mouse (C57BL/6J--bgj/bgj) model of disseminated Mycobacterium avium infection
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The 13-valent pneumococcal conjugate vaccine (Prevenar 13(®), Prevnar 13(®)) [PCV13] consists of 13 serotype-specific polysaccharides of Streptococcus pneumoniae (pneumococcus), each covalently conjugated to a non-toxic immunogenic carrier protein. PCV13 has a well established immunogenicity and tolerability profile in adults, particularly those ≥50 years of age. Results of CAPiTA, a randomized, double-blind, placebo-controlled trial in >84,000 older adults aged ≥65 years, showed that PCV13 was effective in preventing vaccine-type pneumococcal community-acquired pneumonia (CAP), vaccine-type pneumococcal nonbacteraemic (noninvasive) CAP and vaccine-type invasive pneumococcal disease (IPD). These findings, along with changes in pneumococcal serotype distribution and epidemiology of pneumococcal disease, prompted the US Advisory Committee on Immunization Practices (ACIP) to recommend PCV13 in series with 23-valent pneumococcal polysaccharide vaccine (PPVS23) for all adults aged ≥65 years. PCV13 also has a role in preventing pneumococcal disease (pneumonia and IPD) in younger adults with immunocompromising conditions and potentially in those with other underlying medical conditions that increase the risk of pneumococcal disease.
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What does Prevnar 13 consist of?
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The 13-valent pneumococcal conjugate vaccine (Prevenar 13(®), Prevnar 13(®)) [PCV13] consists of 13 serotype-specific polysaccharides of Streptococcus pneumoniae (pneumococcus), each covalently conjugated to a non-toxic immunogenic carrier protein.
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Methods that allow for the manipulation of genes or their products have been highly fruitful for biomedical research. Here, we describe a method that allows the control of protein abundance by a genetically encoded regulatory system. We developed a dormant N-degron that can be attached to the N-terminus of a protein of interest. Upon expression of a site-specific protease, the dormant N-degron becomes deprotected. The N-degron then targets itself and the attached protein for rapid proteasomal degradation through the N-end rule pathway. We use an optimized tobacco etch virus (TEV) protease variant combined with selective target binding to achieve complete and rapid deprotection of the N-degron-tagged proteins. This method, termed TEV protease induced protein inactivation (TIPI) of TIPI-degron (TDeg) modified target proteins is fast, reversible, and applicable to a broad range of proteins. TIPI of yeast proteins essential for vegetative growth causes phenotypes that are close to deletion mutants. The features of the TIPI system make it a versatile tool to study protein function in eukaryotes and to create new modules for synthetic or systems biology.
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What is the function of a protein degron?
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We developed a dormant N-degron that can be attached to the N-terminus of a protein of interest. Upon expression of a site-specific protease, the dormant N-degron becomes deprotected. The N-degron then targets itself and the attached protein for rapid proteasomal degradation through the N-end rule pathway.
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Low-grade tissue inflammation induced by obesity can result in insulin resistance, which in turn is a key cause of type 2 diabetes mellitus. Cells of the innate immune system produce cytokines and other factors that impair insulin signalling, which contributes to the connection between obesity and the onset of type 2 diabetes mellitus. Here, we review the innate immune cells involved in secreting inflammatory factors in the obese state. In the adipose tissue, these cells include proinflammatory adipose tissue macrophages and natural killer cells. We also discuss the role of innate immune cells, such as anti-inflammatory adipose tissue macrophages, eosinophils, group 2 innate lymphoid cells and invariant natural killer T cells, in maintaining an anti-inflammatory and insulin-sensitive environment in the lean state. In the liver, both Kupffer cells and recruited hepatic macrophages can contribute to decreased hepatic insulin sensitivity. Proinflammatory macrophages might also adversely affect insulin sensitivity in the skeletal muscle and pancreatic β-cell function. Finally, this Review provides an overview of the mechanisms for regulating proinflammatory immune responses that could lead to future therapeutic opportunities to improve insulin sensitivity.
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What are Kupffer cells and what is their role?
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liver, both Kupffer cells and recruited hepatic macrophages can contribute to decreased hepatic insulin sensitivity.
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Mutations in the Cu/Zn superoxide dismutase (SOD1) gene are detected in 20% of familial and 3% of sporadic amyotrophic lateral sclerosis (ALS) cases. Although mutant SOD1 is known to induce motor neuron death via multiple adverse acquired functions, its exact pathogenic mechanism is not well defined. SOD1 toxicity is dose dependent; levels of mutant SOD1 protein in transgenic mice determine disease susceptibility, onset and rate of progression. We therefore sought to identify small molecules that reduce SOD1 levels by inhibiting the SOD1 promoter. We tested pyrimethamine (previously reported to suppress SOD1 expression), several compounds currently in trials in human and murine ALS, and a set of 1040 FDA-approved compounds. In a PC12 cell-based assay, no compounds reduced SOD1 promoter activity without concomitant cytotoxicity. Additionally, pyrimethamine failed to repress levels of SOD1 protein in HeLa cells or homogenates of liver, spinal cord and brain of wild-type mice. Thirty-four compounds (including riluzole, ceftriaxone, minocyclin, PBA, lithium, acetylcysteine) in human and mouse ALS trials and an additional set of 1040 FDA-approved compounds also showed no effect on SOD1 promoter activity. This present study thus failed to identify small molecule inhibitors of SOD1 gene expression.
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What is known about clinical efficacy of ceftriaxone for treatment of amyotrophic lateral sclerosis?
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Thirty-four compounds (including riluzole, ceftriaxone, minocyclin, PBA, lithium, acetylcysteine) in human and mouse ALS trials and an additional set of 1040 FDA-approved compounds also showed no effect on SOD1 promoter activity.
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HER-2 overexpression by IHC in archival prostate carcinoma specimens was infrequent. There was no apparent correlation among IHC, ELISA, and FISH, although the sample size was limited. Conclusions regarding the predictive value of HER-2 status on outcome after trastuzumab-based therapy were not reached and were only drawn after larger-scale screening efforts. The authors estimated that 1000 patients need to be screened to complete accrual to a 40-patient efficacy trial.
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Is the monoclonal antibody Trastuzumab (Herceptin) of potential use in the treatment of prostate cancer?
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Conclusions regarding the predictive value of HER-2 status on outcome after trastuzumab-based therapy were not reached and were only drawn after larger-scale screening efforts.
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Ubiquitin is best known for its function in targeting proteins for degradation by the proteasome. Recent studies have revealed several new functions of ubiquitin that are independent of proteasomal degradation. These functions include the novel signaling roles of ubiquitin in DNA repair and the activation of protein kinases such as IkappaB kinase. In both cases, a novel form of polyubiquitin chain linked through lysine-63 of ubiquitin plays an important regulatory role. Monoubiquitination also has signaling roles that are distinct from those of polyubiquitination, as illustrated from the studies of DNA repair. Thus, polyubiquitination and monoubiquitination have emerged as important signaling mechanisms that control diverse physiological and pathological processes.
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What are the outcomes of ubiquitination?
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Ubiquitin is best known for its function in targeting proteins for degradation by the proteasome. Recent studies have revealed several new functions of ubiquitin that are independent of proteasomal degradation. These functions include the novel signaling roles of ubiquitin in DNA repair and the activation of protein kinases such as IkappaB kinase.
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Glycosylphosphatidylinositols (GPIs) are lipid anchors allowing the exposure of proteins at the outer layer of the plasma membrane. In fungi, a number of GPI-anchored proteins (GPI-APs) are involved in the remodeling of the cell wall polymers. GPIs follow a specific biosynthetic pathway in the endoplasmic reticulum. After the transfer of the protein onto the GPI-anchor, a lipid remodeling occurs to substitute the diacylglycerol moiety by a ceramide. In addition to GPI-APs, produces a GPI-anchored polysaccharide, the galactomannan (GM), that remains unique in the fungal kingdom. To investigate the role of the GPI pathway in the biosynthesis of the GM and cell wall organization, the deletion of -coding for a phospholipase required for the first step of the GPI lipid remodeling-was undertaken. Biochemical characterization of the GPI-anchor isolated from GPI-APs showed that the deficient mutant produced a lipid anchor with a diacylglycerol. The absence of a ceramide on GPI-anchors in the mutant led to a mislocation of GPI-APs and to an alteration of the composition of the cell wall alkali-insoluble fraction. On the other hand, the GM isolated from the mutant membranes possesses a ceramide moiety as the parental strain, showing that GPI anchor of the GM follow a distinct unknown biosynthetic pathway.
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What is a GPI anchor?
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Glycosylphosphatidylinositols (GPIs) are lipid anchors allowing the exposure of proteins at the outer layer of the plasma membrane.
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Here, we investigate the potential role of the PARP inhibitor rucaparib (CO-338, formerly known as AG014699 and PF-01367338) for the treatment of sporadic ovarian cancer. We studied the growth inhibitory effects of rucaparib in a panel of 39 ovarian cancer cell lines that were each characterized for mutation and methylation status of BRCA1/2, baseline gene expression signatures, copy number variations of selected genes, PTEN status, and sensitivity to platinum-based chemotherapy. To study interactions with chemotherapy, we used multiple drug effect analyses and assessed apoptosis, DNA fragmentation, and γH2AX formation. Concentration-dependent antiproliferative effects of rucaparib were seen in 26 of 39 (67%) cell lines and were not restricted to cell lines with BRCA1/2 mutations. Low expression of other genes involved in homologous repair (e.g., BCCIP, BRCC3, ATM, RAD51L1), amplification of AURKA or EMSY, and response to platinum-based chemotherapy was associated with sensitivity to rucaparib. Drug interactions with rucaparib were synergistic for topotecan, synergistic, or additive for carboplatin, doxorubicin or paclitaxel, and additive for gemcitabine. Synergy was most pronounced when rucaparib was combined with topotecan, which resulted in enhanced apoptosis, DNA fragmentation, and γH2AX formation. Importantly, rucaparib potentiated chemotherapy independent of its activity as a single agent. PARP inhibition may be a useful therapeutic strategy for a wider range of ovarian cancers bearing deficiencies in the homologous recombination pathway other than just BRCA1/2 mutations. These results support further clinical evaluation of rucaparib either as a single agent or as an adjunct to chemotherapy for the treatment of sporadic ovarian cancer.
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Is rucaparib used for ovarian cancer treatment?
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Here, we investigate the potential role of the PARP inhibitor rucaparib (CO-338, formerly known as AG014699 and PF-01367338) for the treatment of sporadic ovarian cancer.
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A 36-year-old female patient was treated with PUVA for dyshidrotic eczema that had not shown sufficient response to topical therapy over the previous months. PUVA therapy caused acute aggravation of the eczema. Patch testing demonstrated Type IV sensitization to 8-methoxypsoralen in Meladinine solution.
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Is PUVA therapy indicated for eczema treatment?
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PUVA therapy caused acute aggravation of the eczema.
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: Tofacitinib and baricitinib have recently been approved as second-line treatments for Rheumatoid arthritis (RA) though their maximum expected efficacy may be limited by dose-related toxicities. Upadacitinib selectively inhibits Janus Kinase 1 (JAK1) which could potentially reduce JAK2 and JAK3-related side effects. : In this paper, we review a newly developed oral selective JAK inhibitor, upadacitinib for the treatment of RA. The doses of upadacitinib extended-release 15 and 30 mg daily selected in phase III RA studies have shown a near-maximum efficacy in phase II studies. Upadacitinib inhibited radiographic progression and displayed rapid and sustained clinical and functional efficacy in RA when in combination with methotrexate (MTX), upadacitinib was superior to placebo in MTX-Inadequate Responders (IRs) and biologic disease modifying antirheumatic drugs-IRs while as monotherapy, it was superior to MTX in MTX-IRs and MTX-naïve patients. Upadacitinib was superior to adalimumab using ACR70, reduction of pain-VAS and improvement of HAQ-DI. The comparison with abatacept is still ongoing. : Upadacitinib has displayed a rapid and favorable efficacy profile in RA but despite being a selective JAK1 inhibitor appears to have a similar safety profile to less-selective Jakinibs. Longer term safety data are awaited.
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Which molecule is targeted by Upadacitinib?
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Upadacitinib selectively inhibits Janus Kinase 1 (JAK1) which could potentially reduce JAK2 and JAK3-related side effects.
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Alu DNA elements were long considered to be of no biological significance and thus have been only poorly defined. However, in the past Alu DNA elements with well-defined nucleotide sequences have been suspected to contribute to disease, but the role of Alu DNA element transcripts has rarely been investigated. For the first time, we determined in a real-time approach Alu DNA element transcription in buffy coat cells isolated from the blood of humans suffering from sporadic Creutzfeldt-Jakob disease (sCJD) and other neurodegenerative disorders. The reverse transcribed Alu transcripts were amplified and their cDNA sequences were aligned to genomic regions best fitted to database genomic Alu DNA element sequences deposited in the UCSC and NCBI data bases. Our cloned Alu RNA/cDNA sequences were widely distributed in the human genome and preferably belonged to the "young" Alu Y family. We also observed that some RNA/cDNA clones could be aligned to several chromosomes because of the same degree of identity and score to resident genomic Alu DNA elements. These elements, called paralogues, have purportedly been recently generated by retrotransposition. Along with cases of sCJD we also included cases of dementia and Alzheimer disease (AD). Each group revealed a divergent pattern of transcribed Alu elements. Chromosome 2 was the most preferred site in sCJD cases, besides chromosome 17; in AD cases chromosome 11 was overrepresented whereas chromosomes 2, 3 and 17 were preferred active Alu loci in controls. Chromosomes 2, 12 and 17 gave rise to Alu transcripts in dementia cases. The detection of putative Alu paralogues widely differed depending on the disease. A detailed data search revealed that some cloned Alu transcripts originated from RNA polymerase III transcription since the genomic sites of their Alu elements were found between genes. Other Alu DNA elements could be located close to or within coding regions of genes. In general, our observations suggest that identification and genomic localization of active Alu DNA elements could be further developed as a surrogate marker for differential gene expression in disease. A sufficient number of cases are necessary for statistical significance before Alu DNA elements can be considered useful to differentiate neurodegenerative diseases from controls.
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Are Alu elements transcribed?
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Each group revealed a divergent pattern of transcribed Alu elements
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Three statistical/mathematical analyses are carried out on isochore sequences: spectral analysis, analysis of variance, and segmentation analysis. Spectral analysis shows that there are GC content fluctuations at different length scales in isochore sequences. The analysis of variance shows that the null hypothesis (the mean value of a group of GC contents remains the same along the sequence) may or may not be rejected for an isochore sequence, depending on the subwindow sizes at which GC contents are sampled, and the window size within which group members are defined. The segmentation analysis shows that there are stronger indications of GC content changes at isochore borders than within an isochore. These analyses support the notion of isochore sequences, but reject the assumption that isochore sequences are homogeneous at the base level. An isochore sequence may pass a homogeneity test when GC content fluctuations at smaller length scales are ignored or averaged out.
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Does GC content vary markedly within a given isochore?
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The segmentation analysis shows that there are stronger indications of GC content changes at isochore borders than within an isochore.
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Postoperative adjuvant chemotherapy with tegafur-uracil has become the standard of care for patients with completely resected stage I adenocarcinoma according to the positive result from phase III trial conducted in Japan. The effectiveness of tegafur-gimeracil-oteracil potassium in advanced non-small cell lung cancer (NSCLC) is now under investigation in a phase III trial in the first-line treatment in combination with platinum agent as well as in second-line treatment as monotherapy. The evidence of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) such as gefitinib and erlotinib was first confirmed as the second-line treatment for non-selective patients with advanced NSCLC. However, now it is essential to examine some active EGFR gene mutations such as exon 19 deletion or L858R in exon 21, the novel predictive factor for high efficacy of EGFR-TKI, in terms of the risk-benefit balance. For patients with EGFR-mutated advanced NSCLC, the first-line treatment with gefitinib had achieved a significant prolongation of progression-free survival compared with standard platinum doublet chemotherapy in a few phase III trials, and became a new standard of care. Gefitinib is highly effective for patients with advanced NSCLC with EGFR mutation even if their performance status is poor, although one should always pay careful attention to fatal interstitial lung disease.
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Mutations in which gene determine response to both erlotinib and gefitinib?
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The evidence of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) such as gefitinib and erlotinib was first confirmed as the second-line treatment for non-selective patients with advanced NSCLC.
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Anaphylaxis is a rapidly developing, life-threatening, generalized or systemic allergic reaction that is classically elicited by antigen crosslinking of antigen-specific IgE bound to the high-affinity IgE receptor FcεRI on mast cells and basophils. This initiates signals that induce cellular degranulation with release and secretion of vasoactive mediators, enzymes, and cytokines. However, IgE-independent mechanisms of anaphylaxis have been clearly demonstrated in experimental animals. These include IgG-dependent anaphylaxis, which involves the triggering of mediator release by IgG/antigen complex crosslinking of FcγRs on macrophages, basophils, and neutrophils; anaphylaxis mediated by binding of the complement-derived peptides C3a and C5a to their receptors on mast cells, basophils, and other myeloid cells; and direct activation of mast cells by drugs that interact with receptors on these cells. Here we review the mechanisms involved in these IgE-independent forms of anaphylaxis and the clinical evidence for their human relevance. We conclude that this evidence supports the existence of all 3 IgE-independent mechanisms as important causes of human disease, although practical and ethical considerations preclude their demonstration to the degree of certainty possible with animal models. Furthermore, we cite evidence that different clinical situations can suggest different mechanisms as having a primal role in anaphylaxis and that IgE-dependent and distinct IgE-independent mechanisms can act together to increase anaphylaxis severity. As specific agents become available that can interfere with mechanisms involved in the different types of anaphylaxis, recognition of specific types of anaphylaxis is likely to become important for optimal prophylaxis and therapy.
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Is anaphylaxis a results of mast cell activation?
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Anaphylaxis is a rapidly developing, life-threatening, generalized or systemic allergic reaction that is classically elicited by antigen crosslinking of antigen-specific IgE bound to the high-affinity IgE receptor FcεRI on mast cells and basophils.
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DMD gene which is composed of 79 exons is the largest known gene located on X chromosome (Xp21). Point mutations in the dystrophin gene are responsible for 30-35% of cases with DMD/BMD. Mutation analysis of all the exons of the DMD gene is costly in developing countries, therefore, a few of the exons are selected to be analyzed routinely in clinical laboratories. In this study, direct sequencing was used for detection of point mutations in 10 exons of dystrophin gene in patients affected with DMD without detectable large rearrangements. Freely available programs were used to predict the damaging effects of the mutations. Point mutations were successfully detected in three patients. Three novel mutations, two missense mutations located on nonconservative domains and a single nucleotide deletion, were detected. Missense mutations were predicted to change splicing efficiency. Detection of point mutations by DNA analysis followed by prediction of the pathogenecity by using bioinformatic tool might be an asset to provide proper diagnosis or genetic counseling to patients and their family.
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Where is the DMD gene located?
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DMD gene which is composed of 79 exons is the largest known gene located on X chromosome (Xp21).
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Patients with Marfan syndrome used to succumb early in life from cardiovascular complications. With the current rapid advance in medical and surgical care, such patients may now have near-normal longevities. Consequently, rare late-life complications are emerging in these patients and represent challenges to clinicians for their diagnoses and treatments. The authors report a rare case of pelvic pain and genital prolapse from a giant presacral Tarlov cyst in a 67-year-old patient with Marfan syndrome. This 67-year-old Caucasian female presented with progressively severe pelvic pain, intermittent explosive diarrhea, and dysuria. Physical and bimanual examination demonstrated genital prolapse and a nontender, cyst-like mass fixed in the midline. She underwent ultrasound, CT, and eventually MRI evaluations that led to the diagnosis of a giant (6.7 × 6.4 × 6.6 cm) Tarlov cyst originating from the right S-2 nerve root sleeve/sacral foramen with intrapelvic extension. She underwent S1-S2 and S2-S3 laminectomy with obliteration of the Tarlov cyst using aneurysm clips. Postoperatively, her pelvic pain and bowel symptoms resolved and the bladder symptoms improved. The 3-month follow-up CT of abdomen/pelvis demonstrated resolution of the cyst. The present case illustrates that clinicians caring for elderly patients with Marfan syndrome need to increasingly recognize such unusual late-life complications. Also, these large Tarlov cysts can be simply and effectively obliterated with aneurysm clips.
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What is Tarlov Cyst?
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She underwent ultrasound, CT, and eventually MRI evaluations that led to the diagnosis of a giant (6.7 × 6.4 × 6.6 cm) Tarlov cyst originating from the right S-2 nerve root sleeve/sacral foramen with intrapelvic extension.
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The RNA-binding protein HuR, while known to stabilize cytoplasmic mRNAs, is largely nuclear. In this issue of Molecular Cell, Mukherjee et al. (2011) and Lebedeva et al. (2011) identify transcriptome-wide HuR-RNA interactions using PAR-CLIP, unveiling HuR's nuclear role in pre-mRNA processing.
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What is the principle of the PAR-CLIP methodology?
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In this issue of Molecular Cell, Mukherjee et al. (2011) and Lebedeva et al. (2011) identify transcriptome-wide HuR-RNA interactions using PAR-CLIP, unveiling HuR's nuclear role in pre-mRNA processing.
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Membrane and secretory proteins fold in the endoplasmic reticulum (ER), and misfolded proteins may be retained and targeted for ER-associated protein degradation (ERAD). To elucidate the mechanism by which an integral membrane protein in the ER is degraded, we studied the fate of the cystic fibrosis transmembrane conductance regulator (CFTR) in the yeast Saccharomyces cerevisiae. Our data indicate that CFTR resides in the ER and is stabilized in strains defective for proteasome activity or deleted for the ubiquitin-conjugating enzymes Ubc6p and Ubc7p, thus demonstrating that CFTR is a bona fide ERAD substrate in yeast. We also found that heat shock protein 70 (Hsp70), although not required for the degradation of soluble lumenal ERAD substrates, is required to facilitate CFTR turnover. Conversely, calnexin and binding protein (BiP), which are required for the proteolysis of ER lumenal proteins in both yeast and mammals, are dispensable for the degradation of CFTR, suggesting unique mechanisms for the disposal of at least some soluble and integral membrane ERAD substrates in yeast.
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Which biological process in known as Endoplasmic Reticulum-Associated Protein Degradation (ERAD)?
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Membrane and secretory proteins fold in the endoplasmic reticulum (ER), and misfolded proteins may be retained and targeted for ER-associated protein degradation (ERAD).
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The purpose of this study was to compare the detection of trisomy 8 in myelodysplastic syndrome (MDS) patients with interphase fluorescence in situ hybridization (FISH) and cytogenetic karyotype analysis. Using Spectrum Green labeled chromosome 8 centromere probe, interphase FISH was established. The trisomy 8 clones were simultaneously detected in 48 MDS cases with FISH and conventional cytogenetic analysis (CCA). Results showed that the CCA revealed no significant difference of constitutional proportion between MDS-RA and MDS-RAEB with karyotypes of whole +8, partial +8 and one +8. With FISH, detectable rates were 66.1% for whole +8. Partial +8 and sole +8 were significantly higher than one +8 and complex +8, respectively. The percentages of trisomy 8 were similar in MDS-RA and MDS-RAEB. Trisomy 8 was detected in 1 of 15 specimens with normal or abnormal karyotype without trisomy 8 by FISH. There was linear correlation between the percentages of partial +8 detected by FISH and CCA. Two patients received CCA and FISH examination at diagnosis and during treatment, the percentage of trisomy 8 was increased with progress of disease. In conclusion, our results showed that FISH is a sensitive and accurate technique to detect trisomy 8 in MDS patients. It can provide contribute to diagnosis, assessment of curative effect and predicting progress of disease in MDS. Clone size of trisomy 8 does not related to classification of MDS, but sole +8 is seems to see in MDS-RA frequently.
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Which human syndromes have been detected with Fluorescence in situ hybridization (FISH)?
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The trisomy 8 clones were simultaneously detected in 48 MDS cases with FISH and conventional cytogenetic analysis (CCA).
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Nephropathic cystinosis is a rare autosomal recessive lysosomal disease characterized by accumulation of pathognomonic cystine crystals in renal and other tissues of the body. Cystinosis is caused by mutant cystinosin, the cystine transport protein located in lysosomal membranes, leading to systemic deposits of cystine and resultant end organ damage. Cystinosis is rarer in Asians than Caucasians with only a handful of cases reported from India to date. Due to its extreme rarity and clinically insidious presentation in contrast to the infantile form, the diagnosis of juvenile nephropathic cystinosis is frequently delayed or overlooked. Moreover, routine processing and sectioning of paraffin embedded tissues dissolves cystine crystals, making it difficult to diagnose this condition on light microscopic examination alone, mandating electron microscopic (EM) analysis of renal biopsies for an accurate diagnosis of this condition. We describe a case of juvenile nephropathic cystinosis presenting with uveitis and photophobia in a 17-year-old Indian male, diagnosed after EM examination of the patient's renal biopsy for evaluation of nephrotic syndrome. While highlighting the diagnostic utility of EM, we describe a few histopathologic clues which can prompt inclusion of EM analysis of renal biopsies in this setting.
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What is nephropathic cystinosis?
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Nephropathic cystinosis is a rare autosomal recessive lysosomal disease characterized by accumulation of pathognomonic cystine crystals in renal and other tissues of the body.
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The canonical action of the p85α regulatory subunit of phosphatidylinositol 3-kinase (PI3K) is to associate with the p110α catalytic subunit to allow stimuli-dependent activation of the PI3K pathway. We elucidate a p110α-independent role of homodimerized p85α in the positive regulation of PTEN stability and activity. p110α-free p85α homodimerizes via two intermolecular interactions (SH3:proline-rich region and BH:BH) to selectively bind unphosphorylated activated PTEN. As a consequence, homodimeric but not monomeric p85α suppresses the PI3K pathway by protecting PTEN from E3 ligase WWP2-mediated proteasomal degradation. Further, the p85α homodimer enhances the lipid phosphatase activity and membrane association of PTEN. Strikingly, we identified cancer patient-derived oncogenic p85α mutations that target the homodimerization or PTEN interaction surface. Collectively, our data suggest the equilibrium of p85α monomer-dimers regulates the PI3K pathway and disrupting this equilibrium could lead to disease development.
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Does p85α homodimerize?
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p110α-free p85α homodimerizes
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Although anlotinib, a multi-targeted receptor tyrosine kinase inhibitor has been reported have antitumor effects in many preclinical and clinical trials, little is known about its effect on hepatocellular carcinoma (HCC). Here, we have shown the antitumor effects of anlotinib on HCC. Data indicated that anlotinib application significantly inhibited HCC cell viability, proliferation, colony formation, and prompted apoptosis in vitro. Furthermore, animal experiments also illustrated that anlotinib alleviated HCC progression. Mechanically, we demonstrated that anlotinib treatment downregulated the anti-apoptotic protein Bcl-2 and Survivin, but upregulated pro-apoptotic molecule Bax, which accounts for its therapeutic effect on HCC. Pathway analysis has shown decreased phosphorylation levels of Erk and Akt. Together, this study suggests that anlotinib may have a direct antitumor progression effect on HCC by inhibiting Bcl-2 and Survivin expression, promoting Bax expression via inactivating Erk and Akt pathways and could be a promising agent treating HCC.
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What is the mechanism of action of anlotinib?
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Although anlotinib, a multi-targeted receptor tyrosine kinase inhibitor has been reported have antitumor effects in many preclinical and clinical trials, little is known about its effect on hepatocellular carcinoma (HCC).
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In the 1950's it was first observed that mammalian cells exposed to the halogenated deoxyuridines were more sensitive to ultraviolet light and radiation than untreated cells. This prompted early clinical trials with bromodeoxyuridine (BUdR) which showed mixed results. More recently, several Phase I studies, while establishing the feasibility of continuous intravenous (IV) infusion of BUdR, have reported significant dose limiting skin and bone marrow toxicities and have questioned the optimal method of BUdR delivery. To exploit the high mitotic activity of malignant gliomas relative to surrounding normal brain tissue, we have developed a permanently implantable infusion pump system for safe, continuous intraarterial (IA) internal carotid BUdR delivery. Since July 1985, 23 patients with malignant brain tumors (18 grade 4, 5 grade 3) have been treated in a Phase I clinical trial using IA BUdR (400-600 mg/m2/day X 8 1/2 weeks) and focal external beam radiotherapy (59.4 Gy at 1.8 Gy/day in 6 1/2 weeks). Following initial biopsy/surgery the infusion pump system was implanted; BUdR infusion began 2 weeks prior to and continued throughout the 6 1/2 week course of radiotherapy. There have been no vascular complications. Side-effects in all patients have included varying degrees of anorexia, fatigue, ipsilateral forehead dermatitis, blepharitis, and conjunctivitis. Myelosuppression requiring dose reduction occurred in one patient. An overall Kaplan-Meier estimated median survival of 20 months has been achieved. As in larger controlled series, histologic grade and age are prognostically significant. We have shown in a Phase I study that IA BUdR radiosensitization is safe, tolerable, may lead to improved survival, and appears to be an efficacious primary treatment of malignant gliomas.
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Is fatigue prevalent in patients receiving treatment for glioblastoma?
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Side-effects in all patients have included varying degrees of anorexia, fatigue, ipsilateral forehead dermatitis, blepharitis, and conjunctivitis.
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Oncogenic activation of the mitogen-activated protein (MAP) kinase cascade in murine fibroblasts initiates a senescence-like cell cycle arrest that depends on the ARF/p53 tumor suppressor pathway. To investigate whether p53 is sufficient to induce senescence, we introduced a conditional murine p53 allele (p53(val135)) into p53-null mouse embryonic fibroblasts and examined cell proliferation and senescence in cells expressing p53, oncogenic Ras, or both gene products. Conditional p53 activation efficiently induced a reversible cell cycle arrest but was unable to induce features of senescence. In contrast, coexpression of oncogenic ras or activated mek1 with p53 enhanced both p53 levels and activity relative to that observed for p53 alone and produced an irreversible cell cycle arrest that displayed features of cellular senescence. p19(ARF) was required for this effect, since p53(-/-) ARF(-/-) double-null cells were unable to undergo senescence following coexpression of oncogenic Ras and p53. Although the levels of exogenous p53 achieved in ARF-null cells were relatively low, the stabilizing effects of p19(ARF) on p53 could not explain the cooperation between oncogenic Ras and p53 in promoting senescence. Hence, enforced p53 expression without oncogenic ras in p53(-/-) mdm2(-/-) double-null cells produced extremely high p53 levels but did not induce senescence. Taken together, our results indicate that oncogenic activation of the MAP kinase pathway in murine fibroblasts converts p53 into a senescence inducer through both quantitative and qualitative mechanisms.
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Which oncogenes are able to induce cellular senescence?
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our results indicate that oncogenic activation of the MAP kinase pathway in murine fibroblasts converts p53 into a senescence inducer through both quantitative and qualitative mechanisms.
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WAGR syndrome (Wilms' tumor, aniridia, genitourinary abnormalities and mental retardation) and Potocki-Shaffer syndrome are rare contiguous gene deletion syndromes caused by deletions of the 11p14-p12 chromosome region.We present a patient with mental retardation, unilateral cataract, bilateral ptosis, genital abnormalities, seizures and a dysmorphic face. Cytogenetic analysis showed a deletion on 11p that was further characterized using FISH and MLPA analyses. The deletion (11p13-p12) located in the area between the deletions associated with the WAGR and Potocki-Shaffer syndromes had a maximum size of 8.5 Mb and encompasses 44 genes. Deletion of WT1 explains the genital abnormalities observed. As PAX6 was intact the cataract observed cannot be explained by a deletion of this gene. Seizures have been described in Potocki-Shaffer syndrome while mental retardation has been described in both WAGR and Potocki-Shaffer syndrome. Characterization of this patient contributes further to elucidate the function of the genes in the 11p14-p12 chromosome region.
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What the chromsomal location of the gene that is deleted in Potocki-Shaffer syndrome?
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The deletion (11p13-p12) located in the area between the deletions associated with the WAGR and Potocki-Shaffer syndromes had a maximum size of 8.5 Mb and encompasses 44 genes.
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The unmet need for therapies capable of repairing the central nervous system (CNS) damage occurring in many diseases including multiple sclerosis (MS) has sparked the interest of the neurological community for stem cell-based therapies. An exhaustive amount of preclinical data has shown that the intravenous administration of mesenchymal stem cells (MSC), a subset of progenitor cells isolated from many mesodermal tissues, effectively ameliorates experimental autoimmune encephalomyelitis (EAE), a model of MS, through the release of anti-inflammatory and neuroprotective molecules. Based on these results, several small pilot clinical trials in subjects with advanced MS have demonstrated that MSC administration is safe and provided an early signal of clinical effectiveness. The current aim of clinicians and scientists interested in the development of MSC-based strategies for the treatment of MS is to have the ultimate demonstration in large clinical trials that MSC can inhibit CNS inflammation and foster tissue repair as realized clinically, with functional recovery, or visualized by magnetic resonance imaging (MRI).
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Are there clinical trials on stem cells in multiple sclerosis
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Based on these results, several small pilot clinical trials in subjects with advanced MS have demonstrated that MSC administration is safe and provided an early signal of clinical effectiveness. The current aim of clinicians and scientists interested in the development of MSC-based strategies for the treatment of MS is to have the ultimate demonstration in large clinical trials that MSC can inhibit CNS inflammation and foster tissue repair
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Tyrosine kinase growth factor receptors activate MAP kinase by a complex mechanism involving the SH2/3 protein Grb2, the exchange protein Sos, and Ras. The GTP-bound Ras protein binds to the Raf kinase and initiates a protein kinase cascade that leads to MAP kinase activation. Three MAP kinase kinase kinases have been described--c-Raf, c-Mos, and Mekk--that phosphorylate and activate Mek, the MAP kinase kinase. Activated Mek phosphorylates and activates MAP kinase. Subsequently, the activated MAP kinase translocates into the nucleus where many of the physiological targets of the MAP kinase signal transduction pathway are located. These substrates include transcription factors that are regulated by MAP kinase phosphorylation (e.g., Elk-1, c-Myc, c-Jun, c-Fos, and C/EBP beta). Thus the MAP kinase pathway represents a significant mechanism of signal transduction by growth factor receptors from the cell surface to the nucleus that results in the regulation of gene expression. Three MAP kinase homologs have been identified in the rat: Erk1, Erk2, and Erk3. Human MAP kinases that are similar to the rat Erk kinases have also been identified by molecular cloning. The human Erk1 protein kinase has been shown to be widely expressed as a 44-kDa protein in many tissues. The human Erk2 protein kinase is a 41-kDa protein that is expressed ubiquitously. In contrast, a human Erk3-related protein kinase has been found to be expressed at a high level only in heart muscle and brain. The loci of these MAP kinase genes are widely distributed within the human genome: erk2 at 22q11.2; erk1 at 16p11.2; and ek3-related at 18q12-21. In the yeast Saccharomyces cerevisiae, five MAP kinase gene homologs have been described: smkl, mpk1, hog1, fus3, and kss1. Together, these kinases are a more diverse group than the human erks that have been identified. Thus the erks are likely to represent only one subgroup of a larger human MAP kinase gene family. A candidate for this extended family of MAP kinases is the c-Jun NH2-terminal kinase (Jnk), which binds to and phosphorylates the transcription factor c-Jun at the activating sites Ser-63 and Ser-73. Evidence is presented here to demonstrate that Jnk is a distant relative of the MAP kinase group that is activated by dual phosphorylation at Tyr and Thr.
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Which MAP kinase phosphorylates the transcription factor c-jun?
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A candidate for this extended family of MAP kinases is the c-Jun NH2-terminal kinase (Jnk), which binds to and phosphorylates the transcription factor c-Jun at the activating sites Ser-63 and Ser-73
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Clinical and experimental evidence suggest that interleukin-17A (IL-17A; also known as IL-17) is an attractive therapeutic target in rheumatoid arthritis (RA). Rheumatoid synovial tissue produces IL-17A, which causes cartilage and bone degradation in synovial and bone explants. Overexpression of IL-17A induces synovial inflammation and joint destruction in animal RA models. These effects are attenuated in IL-17A-deficient animals and by agents that block IL-17A. Serum IL-17A levels and, to a greater extent, synovial fluid IL-17A levels are elevated in many patients with RA. In some RA cohorts, higher IL-17A levels have been associated with a more severe clinical course. Several IL-17A blockers, including the anti-IL-17A monoclonal antibodies secukinumab and ixekizumab, and the anti-IL-17 receptor subunit A monoclonal antibody brodalumab have been evaluated in phase II clinical trials. Of these, secukinumab is the most advanced with respect to clinical evaluation in RA, with phase III trials ongoing in patients on background methotrexate who had inadequate responses to previous tumor necrosis factor blocker therapy.
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Which molecule is targeted by a monoclonal antibody Secukinumab?
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Several IL-17A blockers, including the anti-IL-17A monoclonal antibodies secukinumab and ixekizumab, and the anti-IL-17 receptor subunit A monoclonal antibody brodalumab have been evaluated in phase II clinical trials
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A large-scale analysis of human polyadenylation signals was carried out in silico. The most canonical AAUAAA hexamer and its 11 single-nucleotide variants that are most frequent in human genes were used to search for polyadenylation signals in the terminal sequences. Out of 18,277 poly(A) sites that were identified from 26,414 human genes, 82.5% of the sites were found to contain at least one of these 12 hexamers as a polyadenylation signal within 40 nucleotides upstream of the poly(A) site. The rest (17.5%) did not contain any of these hexamers, which suggests the existence of yet unknown signals. A total of 20,347 terminal sequences in close proximity to 12 polyadenylation signals were collected using modified EST clustering technique to establish a large-scale database of polyadenylation signals. To characterize the 12 hexamers, the locations of polyadenylation signals that were identified as "authentic" and the uracil contents of the downstream region of the signal were examined. Based on this analysis, the 11 variants of the canonical AAUAAA were identified as possibly forming "functional" signals as AAUAAA. Moreover, the observed frequency of 41.9% for AAUAAA was significantly lower than those of other reports, suggesting that the non-canonical variants are more important in the polyadenylation process than frequently recognized. Since the poly(A) sites processed by those non-canonical variants have not been generally annotated in major gene databases, it is important to determine whether the variant hexamers could work as polyadenylation signals that may be responsible for generating heterogeneity of mRNAs by alternative polyadenylation.
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Which is the RNA sequence of the canonical polyadenylation signal?
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The most canonical AAUAAA hexamer
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Resistance (muscle strengthening) exercise is a key component of exercise recommendations for weight control, yet very little is known about the effects of resistance exercise on appetite. We investigated the effects of resistance and aerobic exercise on hunger and circulating levels of the gut hormones acylated ghrelin and peptide YY (PYY). Eleven healthy male students: age 21.1 +/- 0.3 yr, body mass index 23.1 +/- 0.4 kg/m(2), maximum oxygen uptake 62.1 +/- 1.8 ml.kg(-1).min(-1) (means +/- SE) undertook three, 8-h trials, 1) resistance exercise: a 90-min free weight lifting session followed by a 6.5-h rest period, 2) aerobic exercise: a 60-min run followed by a 7-h rest period, 3) control: an 8-h rest, in a randomized crossover design. Meals were provided 2 and 5 h into each trial. Hunger ratings and plasma concentrations of acylated ghrelin and PYY were measured throughout. Two-way ANOVA revealed significant (P < 0.05) interaction effects for hunger, acylated ghrelin, and PYY, indicating suppressed hunger and acylated ghrelin during aerobic and resistance exercise and increased PYY during aerobic exercise. A significant trial effect was observed for PYY, indicating higher concentrations on the aerobic exercise trial than the other trials (8 h area under the curve: control 1,411 +/- 110, resistance 1,381 +/- 97, aerobic 1,750 +/- 170 pg/ml 8 h). These findings suggest ghrelin and PYY may regulate appetite during and after exercise, but further research is required to establish whether exercise-induced changes in ghrelin and PYY influence subsequent food intake.
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Does physical activity influence gut hormones?
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significant (P < 0.05) interaction effects for hunger, acylated ghrelin, and PYY, indicating suppressed hunger and acylated ghrelin during aerobic and resistance exercise and increased PYY during aerobic exercise
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In December 2013 Bexsero® became available in Germany for vaccination against serogroup B meningococci (MenB). In August 2015 the German Standing Committee on Vaccination (STIKO) endorsed a recommendation for use of this vaccine in persons at increased risk of invasive meningococcal disease (IMD). This background paper summarizes the evidence underlying the recommendation. Bexsero® is based on surface protein antigens expressed by about 80% of circulating serogroup B meningococci in Germany. The paper reviews available data on immunogenicity and safety of Bexsero® in healthy children and adolescents; data in persons with underlying illness and on the effectiveness in preventing clinical outcomes are thus far unavailable.STIKO recommends MenB vaccination for the following persons based on an individual risk assessment: (1) Persons with congenital or acquired immune deficiency or suppression. Among these, persons with terminal complement defects and properdin deficiency, including those under eculizumab therapy, are at highest risk with reported invasive meningococcal disease (IMD) incidences up 10,000-fold higher than in the general population. Persons with asplenia were estimated to have a ~ 20-30-fold increased risk of IMD, while the risk in individuals with other immune defects such as HIV infection or hypogammaglobulinaemia was estimated at no more than 5-10-fold higher than the background risk. (2) Laboratory staff with a risk of exposure to N. meningitidis aerosols, for whom an up to 271-fold increased risk for IMD has been reported. (3) Unvaccinated household (-like) contacts of a MenB IMD index case, who have a roughly 100-200-fold increased IMD risk in the year after the contact despite chemoprophylaxis. Because the risk is highest in the first 3 months and full protective immunity requires more than one dose (particularly in infants and toddlers), MenB vaccine should be administered as soon as possible following identification of the serogroup of the index case.
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What is Bexsero?
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Bexsero® is based on surface protein antigens expressed by about 80% of circulating serogroup B meningococci in Germany
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Severe congenital neutropenia (CN) includes a variety of hematologic disorders characterized by severe neutropenia, with absolute neutrophil counts (ANC) below 0.5 x 10(9)/L, and associated with severe systemic bacterial infections from early infancy. One subtype of CN, Kostmann syndrome, is an autosomal recessive disorder, characterized histopathologically by early-stage maturation arrest of myeloid differentiation. CN with similar clinical features occurs as an autosomal dominant disorder and many sporadic cases also have been reported. This genetic heterogeneity suggests that several pathophysiological mechanisms may lead to this common clinical phenotype. Recent studies on the genetic bases of CN have detected inherited or spontaneous point mutations in the neutrophil elastase gene (ELA 2) in about 60% to 80% of patients and, less commonly, mutations in other genes. Acquisition of additional genetic defects during the course of the disease, for example, granulocyte colony-stimulating factor (G-CSF) receptor gene mutations and cytogenetic aberrations, indicates an underlying genetic instability as a common feature for all congenital neutropenia subtypes. Data on more than 600 patients with CN collected by the Severe Chronic Neutropenia International Registry (SCNIR) demonstrate that, regardless of the particular CN subtype, more than 95% of these patients respond to recombinant human (rHu)G-CSF with ANCs that can be maintained above 1.0 x 10(9)/L. Adverse events include mild splenomegaly, osteoporosis, and malignant transformation into myelodysplasia (MDS)/leukemia. If and how G-CSF treatment impacts on these adverse events is not fully understood. In recent analyses the influence of the G-CSF dose required to achieve neutrophil response (ANC >1,000/microL) in the risk of developing acute myeloid leukemia (AML) has been reported. Hematopoietic stem cell transplantation (HSCT) is still the only treatment available for patients who are refractory to G-CSF treatment.
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Which treatment leads to an increase in neutrophil counts in severe congenital neutropenia?
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Data on more than 600 patients with CN collected by the Severe Chronic Neutropenia International Registry (SCNIR) demonstrate that, regardless of the particular CN subtype, more than 95% of these patients respond to recombinant human (rHu)G-CSF with ANCs that can be maintained above 1.0 x 10(9)/L.
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