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Our results suggest that the majority of protein-coding sequences have evolved to promote protein sequence diversity and to reduce gene knockout under stress. Consequently, transcription-associated mutagenesis increases protein sequence diversity more effectively than does random mutagenesis under stress. Nonrandom transcription-associated mutagenesis under stress should improve the survival of E. coli.
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In which phase of cell cycle does stress-induced transcription-associated mutagenesis (TAM) occur?
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Nonrandom transcription-associated mutagenesis under stress should improve the survival of E.
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The mammalian beta-globin locus is a multigenic, developmentally regulated, tissue-specific locus from which gene expression is regulated by a distal regulatory region, the locus control region (LCR). The functional mechanism by which the beta-globin LCR stimulates transcription of the linked beta-like globin genes remains unknown. The LCR is composed of a series of 5 DNaseI hypersensitive sites (5'HSs) that form in the nucleus of erythroid precursors. These HSs are conserved among mammals, bind transcription factors that also bind to other parts of the locus, and compose the functional components of the LCR. To test the hypothesis that individual HSs have unique properties, homologous recombination was used to construct 5 lines of mice with individual deletions of each of the 5'HSs of the endogenous murine beta-globin LCR. Here it is reported that deletion of 5'HS1 reduces expression of the linked genes by up to 24%, while deletion of 5'HS4 leads to reductions of up to 27%. These deletions do not perturb the normal stage-specific expression of genes from this multigenic locus. In conjunction with previous studies of deletions of the other HSs and studies of deletion of the entire LCR, it is concluded that (1) none of the 5'HSs is essential for nearly normal expression; (2) none of the HSs is required for proper developmental expression; and (3) the HSs do not appear to synergize either structurally or functionally, but rather form independently and appear to contribute additively to the overall expression from the locus.
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What is marked by DNaseI hypersensitive sites?
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The LCR is composed of a series of 5 DNaseI hypersensitive sites (5'HSs) that form in the nucleus of erythroid precursors. These HSs are conserved among mammals, bind transcription factors that also bind to other parts of the locus, and compose the functional components of the LCR.
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HuR is a ligand for nuclear mRNAs containing adenylate-uridylate rich elements in the 3'-untranslated region. Once bound to the mRNA, HuR is recognized by adapter proteins which then facilitate nuclear export of the complex. In the cytosol HuR is thought to function to control stability and translation of its ligand message. In the 3T3-L1 cells HuR is constitutively expressed and localized predominantly to the nucleus in the preadipocytes. However within 30 min of exposure to the differentiation stimulus, the HuR content in the cytosol increases consistent with HuR regulating the availability of relevant mRNAs for translation. Using in vitro RNA gel shifts, we have demonstrated that the C/EBPbeta message is a ligand for HuR and that the single binding site is an adenylate-uridylate rich element in the 3'-untranslated region.
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Which are the main functions of the human HuR (ELAVL1) protein in fibroblasts?
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HuR is a ligand for nuclear mRNAs containing adenylate-uridylate rich elements in the 3'-untranslated region. Once bound to the mRNA, HuR is recognized by adapter proteins which then facilitate nuclear export of the complex. In the cytosol HuR is thought to function to control stability and translation of its ligand message.
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NOX family NADPH oxidases are enzymes whose biological function is electron transport and the generation of reactive oxygen species (ROS). NOX enzymes in mammalian organisms have received most attention. However, NOX enzymes are widely distributed in different kingdoms of life. While they are not found in prokaryotes and most unicellular eukaryotes, they are present in fungi, plants, and animals. The identity of the ancestral NOX is not known, but most likely it: (i) possessed the basic NOX structure consisting of 6 transmembrane domains (containing two assymmetrical hemes) and a long cytoplasmic C-terminal (containing the FAD and NADPH binding sites); and (ii) emerged before the divergence of life into fungi, plants, and animals. During evolution, acquisition of a Ca(2+)-binding EF hand domain by an ancestral NOX, led to NOX5-like isoforms. DUOX isoforms presumably developed from a NOX5-like isoform through the additional acquisition of a peroxidase homology domain. The expression pattern of NOX enzymes is specific to each kingdom of life. Fungi express only ancestral-type isoforms, and plants only NOX5-like isoforms. NOX expression patterns in animals are complex and ancestral NOXes, NOX5-like isoforms and DUOXes are generally found. But there are exceptions; for example rodents lack NOX5 and Caenorhabditis elegans expresses only DUOXes. Biological functions of NOX enzymes include, among others, host defense, post-translational modification of proteins, and regulation cell growth and differentiation. In summary, the invention of NOX enzymes early in the development of life was a success story: there is no evidence of multicellular life without NOX enzymes.
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Is NADPH oxidase 5 expressed in rodents?
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But there are exceptions; for example rodents lack NOX5 and Caenorhabditis elegans expresses only DUOXes.
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The FasL-Fas couple is a general death mediator whose activated signals lead to caspase-8 activation and apoptosis in adult hepatocytes. Suppression of caspase-8 activation and cell death is a protective mechanism modulated by the FLICE-Like Inhibitory Protein (FLIP). Although hepatocyte growth factor (HGF) and its receptor Met are known to mediate cell survival in developing livers, the molecular mechanisms involved in this process are poorly understood. We show here that Met activation by HGF impairs Fas-triggered apoptosis of primary embryonic hepatocytes and cell survival correlates with inhibition of caspase-8 and caspase-3 activities. Furthermore, we found that HGF treatment prevents degradation of FLIPL triggered by Fas activation. In contrast to this, Met activation does not modulate FLIPL levels and its stability in untreated cells, thus showing the specificity of this regulatory mechanism for embryonic hepatocyte survival. Knocking down FLIP expression abolishes the ability of Met to inhibit Fas-triggered hepatocyte death, demonstrating the functional requirement of FLIP in HGF anti-apoptotic signals. By combining genetic and pharmacological approaches, we also demonstrate that the PI3K-Akt pathway is required in embryonic hepatocytes to prevent Fas-triggered FLIP degradation and death. Thus, Met acting on PI3K and Akt ensures high levels of FLIPL, and disruption of this pathway contributes to hepatic apoptosis and possibly to Fas-related liver diseases.
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Is c-met involved in the activation of the Akt pathway?
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Thus, Met acting on PI3K and Akt ensures high levels of FLIPL, and disruption of this pathway contributes to hepatic apoptosis and possibly to Fas-related liver diseases.
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The objective of this study was to assess the incidence and risk factors of infections in 200 SLE outpatients. All outpatients with active or inactive SLE without infections in the previous month were included. They were assessed every 3 months. Major infections were those requiring hospitalization and parental antibiotic therapy; minor infections required oral or topical therapy. Sociodemographic, disease activity using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), therapy and laboratory variables were evaluated. After a follow-up of 22+/-7 months, 65 (32%) patients had infections; 35% of those were major. The most common sites for infection were urinary (26%), skin (23%), systemic (12%), and vaginal (9%). At infection onset, 50 of 65 patients (77%) had disease activity, with a mean SLEDAI score of 6.1. The variables significantly associated with infection in the univariate analyses were the presence of disease activity, SLEDAI score, renal activity, prednisone dose, and IV cyclophosphamide. The only variable associated with infection in the multivariate analyses was a SLEDAI score of 4 or higher. Most infections in SLE outpatients were single, minor, non-life threatening, and associated with disease activity independently of sociodemographic and therapeutic factors.
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A SLEDAI score is associated with Systemic Lupus Erythematosus. What is a SLEDAI score?
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Sociodemographic, disease activity using the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), therapy and laboratory variables were evaluated.
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Anemia and iron deficiency anemia are very common in inflammatory bowel disease (IBD). In most cases, anemia is a consequence of mixed pathogenesis; inflammation and iron deficiency being the most important factors. Iron status should be evaluated carefully, as ferritin is unreliable in the presence of inflammation. It is always necessary to control disease activity; however, supplementation is usually required to fully correct iron deficiencies. Oral iron, intravenous iron, erythropoietin, and blood transfusions can be used in different clinical scenarios. Oral iron may be used in mild cases if the disease has no clinical activity. Intravenous iron should be preferred where oral iron is poorly tolerated or where it has failed in moderate to severe anemia, and in combination with erythropoietin. Iron sucrose is very safe and effective, but not very convenient, as the total needed dose must be divided into several infusions. Ferric carboxymaltose is much more convenient, and has been shown to be more effective than iron sucrose in a large randomized trial. Iron isomaltose shows theoretical promise, but very limited data are available from IBD populations. Blood transfusion can be necessary, especially in acute life-threatening situations, but the trigger for indication should be in the low range. With the correct use of available resources, anemia and iron deficiency should be well controlled in practically all IBD patients.
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Can ferric carboxymaltose be used to treat anemia in inflammatory bowel disease patients?
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Ferric carboxymaltose is much more convenient, and has been shown to be more effective than iron sucrose in a large randomized tria
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Eukaryotic cells store excess fatty acids as neutral lipids, predominantly triacylglycerols and sterol esters, in organelles termed lipid droplets (LDs) that bulge out from the endoplasmic reticulum. LDs are highly dynamic and contribute to diverse cellular functions. The catabolism of the storage lipids within LDs is channeled to multiple metabolic pathways, providing molecules for energy production, membrane building blocks, and lipid signaling. LDs have been implicated in a number of protein degradation and pathogen infection processes. LDs may be linked to prevalent human metabolic diseases and have marked potential for biofuel production. The knowledge accumulated on LDs in recent years provides a foundation for diverse, and even unexpected, future research. This review focuses on recent advances in LD research, emphasizing the diverse physiological roles of LDs in the model system of budding yeast.
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What is the lipid droplet used for in the cell?
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Eukaryotic cells store excess fatty acids as neutral lipids, predominantly triacylglycerols and sterol esters, in organelles termed lipid droplets (LDs) that bulge out from the endoplasmic reticulum.
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In comparative high-throughput sequencing assays, a fundamental task is the analysis of count data, such as read counts per gene in RNA-seq, for evidence of systematic changes across experimental conditions. Small replicate numbers, discreteness, large dynamic range and the presence of outliers require a suitable statistical approach. We present DESeq2, a method for differential analysis of count data, using shrinkage estimation for dispersions and fold changes to improve stability and interpretability of estimates. This enables a more quantitative analysis focused on the strength rather than the mere presence of differential expression. The DESeq2 package is available at http://www.bioconductor.org/packages/release/bioc/html/DESeq2.html webcite.
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Which type of analysis does DeSeq2 perform?
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We present DESeq2, a method for differential analysis of count data, using shrinkage estimation for dispersions and fold changes to improve stability and interpretability of estimates.
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Fanconi anemia (FA) is a heterogeneous disease characterized by spontaneous chromosomal breaks and abnormal DNA repair. Major clinical problems in FA include congenital abnormalities, endocrinopathies, early onset bone marrow failure and increased risk of myelodysplastic syndrome, acute leukemia and solid tumors. To date, 15 different genes have been shown to cause FA, all of which have some role in DNA double-strand break repair. Very few strict genotype-phenotype associations have been identified and clinical manifestations vary widely from patient to patient, most likely due to modifier genes, environment and chance effects. Hematopoietic stem cell transplantation is the only proven cure for the hematopoietic manifestations of FA and aggressive lifelong surveillance for solid tumors is essential.
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What constitutes an increased risk for individuals with Fanconi anemia?
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Fanconi anemia (FA) is a heterogeneous disease characterized by spontaneous chromosomal breaks and abnormal DNA repair. Major clinical problems in FA include congenital abnormalities, endocrinopathies, early onset bone marrow failure and increased risk of myelodysplastic syndrome, acute leukemia and solid tumors
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Invadopodia are matrix-degrading membrane protrusions in invasive carcinoma cells. The mechanisms regulating invadopodium assembly and maturation are not understood. We have dissected the stages of invadopodium assembly and maturation and show that invadopodia use cortactin phosphorylation as a master switch during these processes. In particular, cortactin phosphorylation was found to regulate cofilin and Arp2/3 complex-dependent actin polymerization. Cortactin directly binds cofilin and inhibits its severing activity. Cortactin phosphorylation is required to release this inhibition so cofilin can sever actin filaments to create barbed ends at invadopodia to support Arp2/3-dependent actin polymerization. After barbed end formation, cortactin is dephosphorylated, which blocks cofilin severing activity thereby stabilizing invadopodia. These findings identify novel mechanisms for actin polymerization in the invadopodia of metastatic carcinoma cells and define four distinct stages of invadopodium assembly and maturation consisting of invadopodium precursor formation, actin polymerization, stabilization, and matrix degradation.
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In which process Src, Cortactin and MT1-MMP are playing an essential role?
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Cortactin phosphorylation is required to release this inhibition so cofilin can sever actin filaments to create barbed ends at invadopodia to support Arp2/3-dependent actin polymerization. After barbed end formation, cortactin is dephosphorylated, which blocks cofilin severing activity thereby stabilizing invadopodia.
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Gilbert's syndrome causes mild, unconjugated hyperbilirubinemia and is present in approximately 10% of the Caucasian population. The basis of the disorder is a 70% reduction in bilirubin glucuronidation catalyzed by the UDP-glucuronosyltransferase 1A1 (UGT1A1), which, in Caucasians, is the result of a homozygous TA insertion into the promoter region of the UGT1A1 gene (UGT1A1*28). Homozygous carriers of UGT1A1*28 as well as those with additional UGT1A variants can suffer from severe irinotecan toxicity or jaundice during treatment with the protease inhibitor atazanavir. UGT1A1*28 genotyping identifies patients at risk for drug toxicity and can increase drug safety by dose individualization. Rapid and facile UGT1A1*28 genotyping is therefore of great clinical importance. Two hundred ninety-one patients with suspected Gilbert's syndrome were genotyped using the TaqMan 5'nuclease assay with minor groove binder-non fluorescent quench probes; results were confirmed by direct sequencing. Ninety-six patients (33%) were homozygous for UGT1A1*28, which was verified by direct sequencing of a different PCR product showing 100% concordance with the TaqMan PCR results. We describe a novel UGT1A1*28 genotyping method that employs allelic discrimination by TaqMan PCR. This assay provides a rapid, high-throughput, and cost-effective method for Gilbert's syndrome genotyping, which is of value for pretreatment screening of potential irinotecan toxicity. The method utilizes a technological platform that is widely used in clinical practice and could therefore be easily adapted for routine clinical applications.
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Is the UGT1A1*28 polymorphism associated with irinotecan response in Caucasians?
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Homozygous carriers of UGT1A1*28 as well as those with additional UGT1A variants can suffer from severe irinotecan toxicity
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Avelumab, an anti-programmed death-ligand 1 monoclonal antibody approved for the treatment of metastatic Merkel cell carcinoma and platinum-treated urothelial carcinoma, was initially approved with a 10 mg/kg weight-based dose. We report pharmacokinetic (PK)/pharmacodynamic analyses for avelumab comparing weight-based dosing and a flat 800 mg dose, developed using data from 1,827 patients enrolled in 3 clinical trials (NCT01772004, NCT01943461, and NCT02155647). PK metrics were simulated for weight-based and flat-dosing regimens and summarized by quartiles of weight. Derived exposure metrics were used in simulations of exposure-safety (various tumors) and exposure-efficacy (objective responses; Merkel cell or urothelial carcinoma). Flat dosing was predicted to provide similar exposure to weight-based dosing, with slightly lower variability. Exposure-safety and exposure-efficacy simulations suggested similar benefit:risk profiles for the two dosing regimens. These pharmacometric analyses provided the basis for the US Food and Drug Administration approval of a flat dose of avelumab 800 mg every 2 weeks in approved indications.
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Is avelumab effective for urothelial carcinoma?
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Avelumab, an anti-programmed death-ligand 1 monoclonal antibody approved for the treatment of metastatic Merkel cell carcinoma and platinum-treated urothelial carcinoma, was initially approved with a 10 mg/kg weight-based dose.
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The myocardium of the failing heart undergoes a number of structural alterations, most notably hypertrophy of cardiac myocytes and an increase in extracellular matrix proteins, often seen as primary fibrosis. Connective tissue growth factor (CTGF) is a key molecule in the process of fibrosis and therefore seems an attractive therapeutic target. Regulation of CTGF expression at the promoter level has been studied extensively, but it is unknown how CTGF transcripts are regulated at the posttranscriptional level. Here we provide several lines of evidence to show that CTGF is importantly regulated by 2 major cardiac microRNAs (miRNAs), miR-133 and miR-30. First, the expression of both miRNAs was inversely related to the amount of CTGF in 2 rodent models of heart disease and in human pathological left ventricular hypertrophy. Second, in cultured cardiomyocytes and fibroblasts, knockdown of these miRNAs increased CTGF levels. Third, overexpression of miR-133 or miR-30c decreased CTGF levels, which was accompanied by decreased production of collagens. Fourth, we show that CTGF is a direct target of these miRNAs, because they directly interact with the 3' untranslated region of CTGF. Taken together, our results indicate that miR-133 and miR-30 importantly limit the production of CTGF. We also provide evidence that the decrease of these 2 miRNAs in pathological left ventricular hypertrophy allows CTGF levels to increase, which contributes to collagen synthesis. In conclusion, our results show that both miR-133 and miR-30 directly downregulate CTGF, a key profibrotic protein, and thereby establish an important role for these miRNAs in the control of structural changes in the extracellular matrix of the myocardium.
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Is microRNA(miRNA) 30 involved in post-ischemic cardiac remodeling?
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CTGF is importantly regulated by 2 major cardiac microRNAs (miRNAs), miR-133 and miR-30.
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To clarify the features of the coexistence of active pulmonary tuberculosis in patients with lung cancer, we analyzed clinical data on 25 cases with coexisting lung cancer and active pulmonary tuberculosis encountered at Tokyo National Chest Hospital during the period from 1991 to 1998. There were 23 men and 2 women, with a mean age of 70 years. The incidence of lung cancer among patients with active pulmonary tuberculosis at our hospital was 0.7 per cent, while the incidence of active pulmonary tuberculosis in untreated lung cancer patients at our hospital was 1.9 per cent. We classified the 25 cases into 2 groups as follows: (1) tuberculosis sequential to lung cancer (11 cases) and (2) tuberculosis concurrently detected with lung cancer (14 cases). All patients in the former group were transferred from other hospitals after diagnosing the coexistence of pulmonary tuberculosis during the management of lung cancer. Histological types of lung cancer were squamous cell carcinoma in 12, adenocarcinoma in 9, and small cell carcinoma in 4, and as to the disease stage, stages III to IV were predominant. Analysis on relationship of chest X-ray findings between lung cancer and pulmonary tuberculosis revealed that in general, the location of lung cancer and tuberculosis seemed to be independent. Tuberculosis in the sequential group was more extensive and severer than in the concurrent group. In the concurrent group, treatment for tuberculosis was successful except for one case, and coexisting tuberculosis did not seem to affect the course of lung cancer among this group. However, in the sequential group, 5 patients died within 3 months, 2 of them died of tuberculosis. We consider that in the management of lung cancer, physicians should consider the possibility of coexistent active pulmonary tuberculosis and should not make delay in the diagnosis of active pulmonary tuberculosis.
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What are the 4 histological types of lung cancer?
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ypes of lung cancer were squamous cell carcinoma in 12, adenocarcinoma in 9, and small cell carcinoma in 4, and as to the disease stage, stages III to IV were predominant. Analysis on rela
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The classic signs of vitamin deficiency only occur in states of extreme depletion and are unreliable indicators for early treatment or prophylaxis of alcoholic patients at risk. Post-mortem findings demonstrate that thiamine (vitamin B1) deficiency sufficient to cause irreversible brain damage is not diagnosed ante mortem in 80-90% of these patients. The causes of vitamin deficiency are reviewed with special attention to the inhibition of oral thiamine hydrochloride absorption in man caused by malnutrition present in alcoholic patients or by the direct effects of ethanol on intestinal transport. As the condition of the patient misusing alcohol progresses, damage to brain, liver, gastrointestinal tract, and pancreas continue (with other factors discussed) to further compromise the patient. Decreased intake, malabsorption, reduced storage, and impaired utilization further reduce the chances of unaided recovery. Failure of large oral doses of thiamine hydrochloride to provide an effective treatment for Wernicke's encephalopathy emphasizes the need for adequate and rapid replacement of depleted brain thiamine levels by repeated parenteral therapy in adequate doses.
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Can vitamin B1 deficiency cause encephalopathy?
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Post-mortem findings demonstrate that thiamine (vitamin B1) deficiency sufficient to cause irreversible brain damage is not diagnosed ante mortem in 80-90% of these patients. The causes of vitamin deficiency are reviewed with special attention to the inhibition of oral thiamine hydrochloride absorption in man caused by malnutrition present in alcoholic patients or by the direct effects of ethanol on intestinal transport.
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The significant morbidity and mortality associated with heart failure with reduced (HFrEF) or preserved ejection fraction (HFpEF) justify the search for novel therapeutic agents. The nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway plays an important role in the regulation of cardiovascular function. This pathway is disrupted in HF resulting in decreased protection against myocardial injury. The sGC activator cinaciguat increases cGMP levels by direct, NO-independent activation of sGC, and may be particularly effective in conditions of increased oxidative stress and endothelial dysfunction, and then reduced NO levels, but this comes at the expense of a greater risk of hypotension. Conversely, sGC stimulators (riociguat and vericiguat) enhance sGC sensitivity to endogenous NO, and then exert a more physiological action. The phase 3 VICTORIA trial found that vericiguat is safe and effective in patients with HFrEF and recent HF decompensation. Therefore, adding vericiguat may be considered in individual patients with HFrEF, particularly those at higher risk of HF hospitalization; the efficacy of the sacubitril/valsartan-vericiguat combination in HFrEF is currently unknown.
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What is the mechanism of action of Vericiguat?
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Conversely, sGC stimulators (riociguat and vericiguat) enhance sGC sensitivity to endogenous NO, and then exert a more physiological action.
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Spinal and bulbar muscular atrophy (SBMA), also known as Kennedy's Disease, is a late-onset X-linked progressive neuromuscular disease, which predominantly affects males. The pathological hallmarks of the disease are selective loss of spinal and bulbar motor neurons, accompanied by weakness, atrophy and fasciculations of bulbar and limb muscles. SBMA is caused by a CAG repeat expansion in the gene that encodes the androgen receptor (AR) protein. Disease manifestation is androgen dependent and results principally from a toxic gain of AR function. There are currently no effective treatments for this debilitating disease. It is important to understand the course of the disease in order to target therapeutics to key pathological stages. This is especially relevant in disorders such as SBMA, for which disease can be identified before symptom onset, through family history and genetic testing. To fully characterise the role of muscle in SBMA, we undertook a longitudinal physiological and histological characterisation of disease progression in the AR100 mouse model of SBMA. Our results show that the disease first manifests in skeletal muscle, before any motor neuron degeneration, which only occurs in late-stage disease. These findings reveal that alterations in muscle function, including reduced muscle force and changes in contractile characteristics, are early pathological events in SBMA mice and suggest that muscle-targeted therapeutics may be effective in SBMA.This article has an associated First Person interview with the first author of the paper.
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What is Spinal-bulbar muscular atrophy (SBMA)?
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Spinal and bulbar muscular atrophy (SBMA), also known as Kennedy's Disease, is a late-onset X-linked progressive neuromuscular disease, which predominantly affects males.
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Mutations of the fibrillin gene (FBN1) are known to cause classical Marfan's syndrome, ectopia lentis and neonatal Marfan's syndrome. We have identified a novel missense mutation in exon 28 of the FBN1 gene (R1170H) which is responsible for an atypical marfanoid phenotype characterised by dolichostenomelia and arachnodactyly.
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Which gene mutations cause the Marfan syndrome?
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Mutations of the fibrillin gene (FBN1) are known to cause classical Marfan's syndrome, ectopia lentis and neonatal Marfan's syndrome.
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The mode of action of curare, a well-known competitive antagonist of acetylcholine at the nicotinic receptor, was examined with the single channel recording technique. Curare can open cholinergic channels in rat myotubes, as suggested by Ziskind and Dennis (1978). Moreover another curare molecule can then block the curare-activated open channel, in line with previous results concerning such a mode of action. In adult rat muscle, the partial agonist activity of curare can also be demonstrated, though it is much weaker than in embryonic muscle. It is also shown that in adult muscle cell, the conductance of the channel (activated either by ACh or by curare) is 50-60 pS, i.e., higher than in the myotubes (35 pS).
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Does Curare function by stimulating the acetylcholine receptor?
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The mode of action of curare, a well-known competitive antagonist of acetylcholine at the nicotinic receptor, was examined with the single channel recording technique.
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Macitentan (ACT-064992) is an orally active endothelin receptor antagonist. We first compared the in vitro dissolution characteristics of uncoated and film-coated tablets with hard gelatin capsules containing 10mg ACT-064992. Subsequently, we compared the oral pharmacokinetics of ACT-064992 and its active metabolite ACT-132577 of the coated tablet and the gelatin capsule formulation in 11 male volunteers. The dissolution profile showed a rapid disintegration of all formulations with >90% dissolution of ACT-064992 within 45 min. The pharmacokinetics of ACT-064992 and its metabolite ACT-132577 were comparable for the two formulations. ACT-064992 revealed a slow absorption (median t(max) 8h) and a terminal half-life of approximately 13 h. Bioequivalence criteria were met for AUC(0-t) and AUC(0-infinity). Mean C(max) was 19% lower after ingestion of the tablet compared to capsules with its lower 90% confidence limit below the accepted bioequivalence range. The pharmacokinetics of the metabolite ACT-132577, characterized by a t(max) of approximately 48 h and a terminal half-life of approximately 45 h, was not different between the two formulations. We conclude that the absorption profile of the tablet differs from the capsule in peak but not in total exposure, which is not expected to be of clinical significance.
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Which receptors are targeted by a drug Macitentan?
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Macitentan (ACT-064992) is an orally active endothelin receptor antagonist.
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Super-enhancers are clusters of transcriptional enhancers that drive cell-type-specific gene expression and are crucial to cell identity. Many disease-associated sequence variations are enriched in super-enhancer regions of disease-relevant cell types. Thus, super-enhancers can be used as potential biomarkers for disease diagnosis and therapeutics. Current studies have identified super-enhancers in more than 100 cell types and demonstrated their functional importance. However, a centralized resource to integrate all these findings is not currently available. We developed dbSUPER (http://bioinfo.au.tsinghua.edu.cn/dbsuper/), the first integrated and interactive database of super-enhancers, with the primary goal of providing a resource for assistance in further studies related to transcriptional control of cell identity and disease. dbSUPER provides a responsive and user-friendly web interface to facilitate efficient and comprehensive search and browsing. The data can be easily sent to Galaxy instances, GREAT and Cistrome web-servers for downstream analysis, and can also be visualized in the UCSC genome browser where custom tracks can be added automatically. The data can be downloaded and exported in variety of formats. Furthermore, dbSUPER lists genes associated with super-enhancers and also links to external databases such as GeneCards, UniProt and Entrez. dbSUPER also provides an overlap analysis tool to annotate user-defined regions. We believe dbSUPER is a valuable resource for the biology and genetic research communities.
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What is the dbSUPER database?
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We developed dbSUPER (http://bioinfo.au.tsinghua.edu.cn/dbsuper/), the first integrated and interactive database of super-enhancers, with the primary goal of providing a resource for assistance in further studies related to transcriptional control of cell identity and disease. dbSUPER provides a responsive and user-friendly web interface to facilitate efficient and comprehensive search and browsing. The data can be easily sent to Galaxy instances, GREAT and Cistrome web-servers for downstream analysis, and can also be visualized in the UCSC genome browser where custom tracks can be added automatically. The data can be downloaded and exported in variety of formats. Furthermore, dbSUPER lists genes associated with super-enhancers and also links to external databases such as GeneCards, UniProt and Entrez. dbSUPER also provides an overlap analysis tool to annotate user-defined regions.
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Diphtheria is a serious upper respiratory tract disease caused by the diphtheria toxin (DT) secreted from the bacteria Corynebacterium diphtheriae. Vaccination is the best way to protect against this infectious disease. Diphtheria vaccines are prepared by isolating, purifying and chemically deactivating DT. Although toxoids have been used for decades in immunization, there is still little understanding at the molecular level of the process of toxoid preparation, and how chemical treatment enhances their immunogenicity. We have undertaken an NMR study of the catalytic domain as a first step in understanding the molecular details involved in vaccine antigen preparation. Here we report a near complete assignment for the backbone and side chain resonances of the diphtheria toxin catalytic domain.
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Which bacteria cause diphtheria?
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Diphtheria is a serious upper respiratory tract disease caused by the diphtheria toxin (DT) secreted from the bacteria Corynebacterium diphtheriae.
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The human pseudoautosomal region 1 (PAR1) is essential for the obligatory X-Y crossover in male meiosis. Despite its critical role, comparative studies of human and mouse pseudoautosomal genes have been limited owing to the scarcity of genes conserved between the two species. Human CD99 is a 32-kDa cell surface protein that is encoded by the MIC2 gene localized to the PAR1. Although several sequences such as CD99L2, PBDX, and CD99L1 are related to CD99, its murine ortholog, Cd99, has not yet been identified. Here we report a novel mouse Cd99, designated D4, which shows overall sequence homology to CD99, with the highest conservation between the two genes being found in the transmembrane regions. In addition, the D4 protein displays biochemical characteristics, functional homology, and expression patterns similar to those of CD99. The D4 gene is localized on an autosome, chromosome 4, reflecting a common mapping feature with other mouse orthologs of human PAR1 genes. Furthermore, a phylogenetic analysis of CD99-related genes confirmed that the D4 gene is indeed an ortholog of CD99 and exhibits the accelerated evolution pattern of CD99 orthologs, as compared to the CD99L2 orthologs. On the basis of these findings, we suggest that CD99 belongs to the ancient PAR genes, and that the rapid interspecies divergence of its present sequence and map position is due to a high recombination frequency and the occurrence of chromosomal translocation, supporting the addition-attrition hypothesis for PAR evolution.
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Is CD99 encoded by MIC2 gene?
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Human CD99 is a 32-kDa cell surface protein that is encoded by the MIC2 gene localized to the PAR1.
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The course and prognostic value of disease activity measured by the validated Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was investigated in 68 newly diagnosed black Caribbean cases. A high percentage of patients had clinical renal involvement (78%). Disease activity at onset was mild to moderate (SLEDAI < or = 10) in 36% of patients; about half never reached a higher SLEDAI score, whereas the other half advanced to higher disease activity (SLEDAI > 10). SLEDAI scores decreased significantly over time from diagnosis. Within 3 months after disease onset, 54% of patients reached their maximum SLEDAI scores. There were no differences in clinical features or survival between these patients and those with later (mean, 35 months) maximum disease activity, although the latter had more frequent disease flares. Overall survival was poor (91% and 56% at 1 and 5 years, respectively). High persistent disease activity (weighted average of SLEDAI scores > 10) was independently associated with decreased survival, whereas a high initial SLEDAI, a high maximum SLEDAI, and an increase number of flares were not. The main cause of death was infection, which often was associated with active disease (mean SLEDAI at death, 16 +/- 8.9). SLEDAI was a practical and reliable way of evaluating disease activity but was of limited prognostic value.
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A SLEDAI score is associated with Systemic Lupus Erythematosus. What is a SLEDAI score?
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The course and prognostic value of disease activity measured by the validated Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) was investigated in 68 newly diagnosed black Caribbean cases.
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Nemaline myopathy (NM) is the most common congenital myopathy and is caused by mutations in various genes including NEB (nebulin), TPM2 (beta-tropomyosin), TPM3 (gamma-tropomyosin), and ACTA1 (skeletal alpha-actin). 20-25% of NM cases carry ACTA1 defects and these particular mutations usually induce substitutions of single residues in the actin protein. Despite increasing clinical and scientific interest, the contractile consequences of these subtle amino acid substitutions remain obscure. To decipher them, in the present study, we originally recorded and analysed the mechanics as well as the X-ray diffraction patterns of human membrane-permeabilized single muscle fibres with a particular peptide substitution in actin, i.e. p.Phe352Ser. Results unravelled an unexpected cascade of molecular and cellular events. During contraction, p.Phe352Ser greatly enhances the strain of individual cross-bridges. Paradoxically, p.Phe352Ser also slightly lowers the number of cross-bridges by altering the rate of myosin head attachment to actin monomers. Overall, at the cell level, these divergent mechanisms conduct to an improved steady-state force production. Such results provide new surprising scientific insights and crucial information for future therapeutic strategies.
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Are ACTA1 (alpha actin) and NEB (nebulin) genes related to nemaline myopathy?
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Nemaline myopathy (NM) is the most common congenital myopathy and is caused by mutations in various genes including NEB (nebulin), TPM2 (beta-tropomyosin), TPM3 (gamma-tropomyosin), and ACTA1 (skeletal alpha-actin).
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The prevalence of the metabolic syndrome (MetS), a cluster of cardiovascular risk factors associated with obesity and insulin resistance, is dramatically increasing in Western and developing countries. This disorder is not only associated with a higher risk of appearance of type 2 diabetes and cardiovascular events, but impacts on the liver in different ways. Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic manifestation of MetS, and is characterized by triglyceride accumulation and a variable degree of hepatic injury, inflammation, and repair. In the presence of significant hepatocellular injury and inflammation, the picture is defined 'nonalcoholic steatohepatitis' (NASH), that has the potential to progress to advanced fibrosis and cirrhosis. Diagnosis of NASH is based on a liver biopsy, and active search for noninvasive tests is ongoing. Progression of steatohepatitis to advanced fibrosis or cirrhosis has been shown in at least one third of patients followed with paired biopsies. Presence of NASH is associated with lower life expectancy, both due to liver-related death and to an increase in cardiovascular events. The appearance of NAFLD is mainly dependent on increased flow of fatty acids derived from an excess of lipolysis from insulin-resistant adipose tissue. Development of NASH is based on lipotoxicity and is influenced by signals derived from outside the liver and from intrahepatic activation of inflammatory and fibrogenic pathways. The presence of the MetS is also associated with worse outcomes in patients with cirrhosis due to any causes, and has complex interactions with hepatitis C virus infection. Moreover, MetS poses a higher risk of development of hepatocellular carcinoma, not necessarily through the development of NASH-related cirrhosis. In conclusion, the presence of metabolic alterations has a severe and multifaceted impact on the liver, and is responsible for a higher risk of liver-dependent and -independent mortality.
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Which are the mains risk factors of metabolic syndrome?
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alence of the metabolic syndrome (MetS), a cluster of cardiovascular risk factors associated with obesity and insulin resistance, is dramatically increasing in Western and developing countries. This disorder is not only associated with a higher risk of appearance of type 2 diabetes and cardiovascular events, but impacts on the liver in different ways. Nonalc
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Werner's syndrome (WS) or progeria adultorum is a heritable autosomal recessive disease in which the aging process is accelerated, just after puberty. It is caused by mutations in the WRN gene, which encodes a member of the RECQ family of DNA helicases and has a role in DNA repair. WS is being more appropriately recognized as a condition in which the lack of WRN protein results in an overall decline in the normal physiological functions of various organs rather than premature aging. Here, we describe a rare case of WS with a novel mutation from India. Our patient was an adult male with a history of growth arrest since puberty and other clinical features such as sclerodermatous skin changes, premature graying and thinning of hair, bilateral cataract, a single non-healing ulcer, hypothyroidism, underdeveloped secondary sexual characters with hypogonadism, infertility, squeaky voice, and early signs of arteriosclerosis. On genetic analysis, he was found to have a homozygous pathogenic variant c.3190C>T in exon 26 of the WRN gene, which has never been reported in WS.
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Is progeria caused by an autosomal recessive gene?
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Werner's syndrome (WS) or progeria adultorum is a heritable autosomal recessive disease in which the aging process is accelerated, just after puberty. It is
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A number of studies show the efficacy of methotrexate (MTX) for rheumatoid arthritis (RA) in general. However, is there any reason to single this drug out for early RA? Mechanistically, it probably works differently in RA than in cancer, at least in part. Thus, in addition to dihydrofolate reductase-related effects, MTX inhibits aminoimidazocarboxamide transformylase, decreases leukotriene B4 production, and increases adenosine release at concentrations achieved with low-dose MTX regimens. Clinically, it is well tolerated over relatively long periods. Further, a recent meta-analysis of radiology studies shows that MTX compares favorably with intramuscular gold and is better than azathioprine. Toxicity remains a concern in treating early RA, particularly as pulmonary "hypersensitivity reactions" continue (1% to 7.6%), infections (both fungal and perioperative) are documented, and more cirrhosis is found. With all of the above in mind, the use of MTX seems reasonable but not necessarily uniformly appropriate and not yet proved for early RA. Studies of MTX in early RA, particularly in combination with other drugs, are only beginning.
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Is methotrexate used for the treatment of Rheumatoid Arthritis (RA)?
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A number of studies show the efficacy of methotrexate (MTX) for rheumatoid arthritis (RA) in general.
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Heme is critical for a variety of cellular processes, but excess intracellular heme may result in oxidative stress and membrane injury. Feline leukemia virus subgroup C receptor (FLVCR1), a member of the SLC49 family of four paralogous genes, is a cell surface heme exporter, essential for erythropoiesis and systemic iron homeostasis. Disruption of FLVCR1 function blocks development of erythroid progenitors, likely due to heme toxicity. Mutations of SLC49A1 encoding FLVCR1 are noted in patients with a rare neurodegenerative disorder: posterior column ataxia with retinitis pigmentosa. FLVCR2 is highly homologous to FLVCR1 and may function as a cellular heme importer. Mutations of SLC49A2 encoding FLVCR2 are observed in Fowler syndrome, a rare proliferative vascular disorder of the brain. The functions of the remaining members of the SLC49 family, MFSD7 and DIRC2 (encoded by the SLC49A3 and SLC49A4 genes), are unknown, although the latter is implicated in hereditary renal carcinomas. SLC48A1 (heme responsive gene-1, HRG-1), the sole member of the SLC48 family, is associated with the endosome and appears to transport heme from the endosome into the cytosol.
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Which SLC family is FLVCR1 a member of?
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Feline leukemia virus subgroup C receptor (FLVCR1), a member of the SLC49 family of four paralogous genes, is a cell surface heme exporter, essential for erythropoiesis and systemic iron homeostasis.
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The selective degradation of cytosolic proteins in lysosomes by chaperone-mediated autophagy depends, at least in part, on the levels of a substrate receptor at the lysosomal membrane. We have previously identified this receptor as the lysosome-associated membrane protein type 2a (lamp2a) and showed that levels of lamp2a at the lysosomal membrane directly correlate with the activity of the proteolytic pathway. Here we show that levels of lamp2a at the lysosomal membrane are mainly controlled by changes in its half-life and its distribution between the lysosomal membrane and the matrix. The lysosomal degradation of lamp2a requires the combined action of at least two different proteolytic activities at the lysosomal membrane. Lamp2a is released from the membrane by the action of these proteases, and then the truncated lamp2a is rapidly degraded within the lysosomal matrix. Membrane degradation of lamp2a is a regulated process that is inhibited in the presence of substrates for chaperone-mediated autophagy and under conditions that activate that type of autophagy. Uptake of substrate proteins also results in transport of some intact lamp2a from the lysosomal membrane into the matrix. This fraction of lamp2a can be reinserted back into the lysosomal membrane. The traffic of lamp2a through the lysosomal matrix is not mediated by vesicles, and lamp2a reinsertion requires the lysosomal membrane potential and protein components of the lysosomal membrane. The distribution of lamp2a between the lysosomal membrane and matrix is a dynamic process that contributes to the regulation of lysosomal membrane levels of lamp2a and consequently to the activity of the chaperone-mediated autophagic pathway.
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Which is the receptor for substrates of Chaperone Mediated Autophagy?
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We have previously identified this receptor as the lysosome-associated membrane protein type 2a (lamp2a)
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miRNAs are short (20-23 nt) RNAs that are loaded into proteins of the Argonaute (AGO) family and guide them to partially complementary target sites on mRNAs, resulting in mRNA destabilization and/or translational repression. It is estimated that about 60% of the mammalian genes are potentially regulated by miRNAs, and therefore methods for experimental miRNA target determination have become valuable tools for the characterization of posttranscriptional gene regulation. Here we present a step-by-step protocol and guidelines for the computational analysis for the large-scale identification of miRNA target sites in cultured cells by photoactivatable ribonucleoside enhanced crosslinking and immunoprecipitation (PAR-CLIP) of AGO proteins.
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What is the principle of the PAR-CLIP methodology?
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Here we present a step-by-step protocol and guidelines for the computational analysis for the large-scale identification of miRNA target sites in cultured cells by photoactivatable ribonucleoside enhanced crosslinking and immunoprecipitation (PAR-CLIP) of AGO proteins.
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Thyroid hormone (TH) transport into the brain is not only pivotal for development and differentiation, but also for maintenance and regulation of adult central nervous system (CNS) function. In this review, we highlight some key factors and structures regulating TH uptake and distribution. Serum TH binding proteins play a major role for the availability of TH since only free hormone concentrations may dictate cellular uptake. One of these proteins, transthyretin is also present in the cerebrospinal fluid (CSF) after being secreted by the choroid plexus. Entry routes into the brain like the blood-brain-barrier (BBB) and the blood-CSF-barrier will be explicated regarding fetal and adult status. Recently identified TH transmembrane transporters (THTT) like monocarboxylate transporter 8 (Mct8) play a major role in uptake of TH across the BBB but as well in transport between cells like astrocytes and neurons within the brain. Species differences in transporter expression will be presented and interference of TH transport by endogenous and exogenous compounds including endocrine disruptors and drugs will be discussed.
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What is the function of transthyretin in cerebrospinal fluid?
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Serum TH binding proteins play a major role for the availability of TH since only free hormone concentrations may dictate cellular uptake. One of these proteins, transthyretin is also present in the cerebrospinal fluid (CSF) after being secreted by the choroid plexus. Entry routes into the brain like the blood-brain-barrier (BBB) and the blood-CSF-barrier will be explicated regarding fetal and adult status.
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An activating BRAF (V600E) kinase mutation occurs in approximately half of melanomas. Recent clinical studies have demonstrated that vemurafenib (PLX4032) and dabrafenib, potent and selective inhibitors of mutant v-raf murine sarcoma viral oncogene homolog B1 (BRAF), exhibit remarkable activities in patients with V600 BRAF mutant melanomas. However, acquired drug resistance invariably develops after the initial treatment. Identification of acquired resistance mechanisms may inform the development of new therapies that elicit long-term responses of melanomas to BRAF inhibitors. Here we report that increased expression of AEBP1 (adipocyte enhancer-binding protein 1) confers acquired resistance to BRAF inhibition in melanoma. AEBP1 is shown to be highly upregulated in PLX4032-resistant melanoma cells because of the hyperactivation of the PI3K/Akt-cAMP response element-binding protein (CREB) signaling pathway. This upregulates AEBP1 expression and thus leads to the activation of NF-κB via accelerating IκBa degradation. In addition, inhibition of the PI3K/Akt-CREB-AEBP1-NF-κB pathway greatly reverses the PLX4032-resistant phenotype of melanoma cells. Furthermore, increased expression of AEBP1 is validated in post-treatment tumors in patients with acquired resistance to BRAF inhibitor. Therefore, these results reveal a novel PI3K/Akt-CREB-AEBP1-NF-κB pathway whose activation contributes to acquired resistance to BRAF inhibition, and suggest that this pathway, particularly AEBP1, may represent a novel therapeutic target for treating BRAF inhibitor-resistant melanoma.
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Are BRAF mutations common in melanoma?
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An activating BRAF (V600E) kinase mutation occurs in approximately half of melanomas.
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Duchenne muscular dystrophy (DMD), glycerol kinase deficiency (GKD), and adrenal hypoplasia congenita (AHC) can occur together as part of a contiguous gene syndrome located at chromosome Xp21, GKD can manifest with recurrent episodes of vomiting, acidemia, mental retardation, or stupor. Involvement of the AHC gene can produce life-threatening adrenal insufficiency, sexual ambiguity, and electrolyte abnormalities. These associated conditions can make the diagnosis of DMD difficult. Neuromuscular specialists need to be aware of this contiguous gene syndrome because the potential life-threatening complications of GKD and AHC can be treated.
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Where is the DMD gene located?
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Duchenne muscular dystrophy (DMD), glycerol kinase deficiency (GKD), and adrenal hypoplasia congenita (AHC) can occur together as part of a contiguous gene syndrome located at chromosome Xp21, GKD can manifest with recurrent episodes of vomiting, acidemia, mental retardation, or stupor.
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The enzyme steroid 5 alpha-reductase utilizes NADPH to reduce the double bonds of a variety of steroid substrates with generalized 3-oxo, delta 4,5 structures. One substrate for this membrane-bound enzyme is testosterone, whose reduction to dihydrotestosterone is required for the embryonic differentiation of the external male genitalia and prostate. There are two 5 alpha-reductase isozymes, designated types 1 and 2, which have different biochemical and pharmacological properties. Inherited deficiencies of 5 alpha-reductase type 2 result in a form of male pseudohermaphroditism in which the external genitalia fail to develop normally. Here, nine additional mutations in the 5 alpha-reductase 2 gene in subjects with 5 alpha-reductase deficiency are described. The biochemical consequences of these mutations, as well as 13 previously identified missense mutations, were characterized by recreating the mutations in an expressible cDNA and transfecting into mammalian cells. Twelve of the 22 mutations inactivated the enzyme. The remaining 10 mutations impaired enzyme function by affecting either substrate or cofactor binding. Almost all mutations decreased the half-life of the protein, and all but one of the impaired enzymes had an altered pH optimum. The mutations provide insight into functional domains in the protein as well as an unusual acidic pH optimum characteristic of the 5 alpha-reductase type 2 isozyme.
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Does steroid 5A-Reductase deficiency lead to hermaphroditism?
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Inherited deficiencies of 5 alpha-reductase type 2 result in a form of male pseudohermaphroditism in which the external genitalia fail to develop normally.
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Oculocutaneous albinism type 1 (OCA1) results from mutations in the tyrosinase gene, which lead to partial or complete loss of activity of the corresponding enzyme. A large number of mutations have been identified worldwide, providing insight into the pathogenesis of the disorder. We performed ophthalmic and dermatological exams on 30 Lebanese subjects with oculocutaneous albinism, then screened for mutations in the tyrosinase gene in an effort to establish the molecular basis of the disorder in our population and correlate it with phenotypic findings. The five exons of the gene together with the exon-intron boundaries and part of the promoter region were sequenced. Mutations were found in a total of 14 patients (47%) while no mutation was identified in the sequenced regions in 53% of patients. Fourteen different mutations were identified of which eight were novel while six had been previously reported. Mutations were mainly seen in patients with clinical findings, suggestive of OCA1A (64% of patients with OCA1A versus 25% of patients with OCA1B); therefore, the absence of mutations in some of the other patients may indicate the involvement of other genes.
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Which mutated enzyme is responsible for oculocutaneous 1 (OCA1)-type albinism?
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Oculocutaneous albinism type 1 (OCA1) results from mutations in the tyrosinase gene, which lead to partial or complete loss of activity of the corresponding enzyme.
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Givosiran (Givlaari™) is an aminolevulinate synthase 1 (ALAS1)-directed small interfering RNA (siRNA) covalently linked to a ligand to enable specific delivery of the siRNA to hepatocytes. This results in downregulation of ALAS1 mRNA and prevents accumulation of neurotoxic δ-aminolevulinic acid and porphobilinogen levels that are associated with acute porphyria attacks. Givosiran is being developed by Alnylam Pharmaceuticals for the treatment of acute hepatic porphyria (AHP). In November 2019, givosiran was approved in the USA for the treatment of adults with AHP based on the positive results from the multinational, phase III ENVISION trial. In the EU, givosiran received a positive opinion in January 2020 for the treatment of AHP in adults and adolescents aged 12 years and older. This article summarizes the milestones in the development of givosiran leading to this first approval for the treatment of adults with AHP.
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Describe the mechanism of action of Givosiran.
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Givosiran (Givlaari™) is an aminolevulinate synthase 1 (ALAS1)-directed small interfering RNA (siRNA) covalently linked to a ligand to enable specific delivery of the siRNA to hepatocytes. This results in downregulation of ALAS1 mRNA and prevents accumulation of neurotoxic δ-aminolevulinic acid and porphobilinogen levels that are associated with acute porphyria attacks.
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The deficiency of α-Klotho in mice causes phenotypes resembling human age-associated disorders at 3-4 weeks after birth and shows short lifespans of ∼2 months. One of the crucial symptoms is pulmonary emphysema, although α-Klotho is not expressed in the lungs. α-Klotho secreted from the kidneys is probably involved in the pathology of emphysema because kidney-specific knockout mice exhibit emphysematous structural changes. We examined whether any glycan changes in α-Klotho mouse lungs were observed, because α-Klotho is reported to have glycosidase activity. Here, we found the accumulation of heparan sulphate in the microsomal fraction of α-Klotho mouse lungs. Meanwhile, a disintegrin and metalloproteinase 17 (ADAM17) expression was decreased in α-Klotho mice. From these results, it is thought that the increase in heparan sulphate is due to insufficient cleavage of the core protein by ADAM17. Additionally, a reduction in α-Klotho and a decline of ADAM17 were also observed both in normal aged mice and in senescence marker protein-30 (SMP30) knockout mice, a mouse model of premature ageing. Thus, the decrease in ADAM17 is caused by the reduction in α-Klotho. These may be involved in the deterioration of lung function during ageing and may be associated with the pathology of pulmonary emphysema.
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Where is the klotho protein primarily expressed in the body
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One of the crucial symptoms is pulmonary emphysema, although α-Klotho is not expressed in the lungs. α-Klotho secreted from the kidneys is probably involved in the pathology of emphysema because kidney-specific knockout mice exhibit emphysematous structural changes.
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Ciliopathy encompasses a diverse group of autosomal recessive genetic disorders caused by mutations in genes coding for components of the primary cilia. Skeletal ciliopathy forms a subset of ciliopathies characterized by distinctive skeletal changes. Common skeletal ciliopathies include Jeune asphyxiating thoracic dysplasia, Ellis-van Creveld syndrome, Sensenbrenner syndrome, and short-rib polydactyly syndromes. These disorders share common clinical and radiological features. The clinical hallmarks comprise thoracic hypoplasia with respiratory failure, body disproportion with a normal trunk length and short limbs, and severely short digits occasionally accompanied by polydactyly. Reflecting the clinical features, the radiological hallmarks consist of a narrow thorax caused by extremely short ribs, normal or only mildly affected spine, shortening of the tubular bones, and severe brachydactyly with or without polydactyly. Other radiological clues include trident ilia/pelvis and cone-shaped epiphysis. Skeletal ciliopathies are commonly associated with extraskeletal anomalies, such as progressive renal degeneration, liver disease, retinopathy, cardiac anomalies, and cerebellar abnormalities. In this article, we discuss the radiological pattern recognition approach to skeletal ciliopathies. We also describe the clinical and genetic features of skeletal ciliopathies that the radiologists should know for them to play an appropriate role in multidisciplinary care and scientific advancement of these complicated disorders.
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What is a ciliopathy?
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Ciliopathy encompasses a diverse group of autosomal recessive genetic disorders caused by mutations in genes coding for components of the primary cilia.
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Contrave, under development by Orexigen Therapeutics Inc for the potential treatment of obesity, is an oral, sustained-release combination of the dopamine and norepinephrine reuptake antagonist bupropion and the opioid antagonist naltrexone. The proposed dual mechanism of action of the compound involves complementary stimulation of central melanocortin pathways, resulting in increased energy expenditure and reduced appetite. At the time of publication, Contrave was being assessed in phase III clinical trials. Preliminary data demonstrated placebo-subtracted weight losses of 3 to 7% and improvements in obesity-related comorbidities and cardiovascular risk factors. The primary adverse effect leading to discontinuation of treatment was nausea. Assuming that the results of the Contrave phase III clinical program reaffirm the efficacy and safety of the drug combination, this agent could be approved and launched to become a market leader in the anti-obesity therapeutic arena.
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Which drugs are included in the Contrave pill?
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Contrave, under development by Orexigen Therapeutics Inc for the potential treatment of obesity, is an oral, sustained-release combination of the dopamine and norepinephrine reuptake antagonist bupropion and the opioid antagonist naltrexone. T
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We have recently reported that topoisomerase 1 (Top1) cooperates with ASF/SF2, a splicing factor of the SR family, to prevent unscheduled replication fork arrest and genomic instability in human cells. Our results suggest that Top1 execute this function by suppressing the formation of DNA-RNA hybrids during transcription, these so-called R-loops interfering with the progression of replication forks. Using ChIP-chip, we have shown that γ-H2AX, a marker of DNA damage, accumulates at gene-rich regions of the genome in Top1-deficient cells. This is best illustrated at histone genes, which are highly expressed during S phase and display discrete γ-H2AX peaks on ChIP-chip profiles. Here, we show that these γ-H2AX domains are different from those induced by camptothecin, a Top1 inhibitor inducing double-strand DNA breaks throughout the genome. These data support the view that R-loops promote genomic instability at specific sites by blocking fork progression and inducing chromosome breaks. Whether this type of transcription-dependent fork arrest contributes to the replication stress observed in precancerous lesions is an important question that deserves further attention.
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Do R-loops tend to form at sites of DNA replication?
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Our results suggest that Top1 execute this function by suppressing the formation of DNA-RNA hybrids during transcription, these so-called R-loops interfering with the progression of replication forks.
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Transcription-coupled DNA repair uses components of the transcription machinery to identify DNA lesions and initiate their repair. These repair pathways are complex, so their mechanistic features remain poorly understood. Bacterial transcription-coupled repair is initiated when RNA polymerase stalled at a DNA lesion is removed by Mfd, an ATP-dependent DNA translocase. Here we use single-molecule DNA nanomanipulation to observe the dynamic interactions of Escherichia coli Mfd with RNA polymerase elongation complexes stalled by a cyclopyrimidine dimer or by nucleotide starvation. We show that Mfd acts by catalysing two irreversible, ATP-dependent transitions with different structural, kinetic and mechanistic features. Mfd remains bound to the DNA in a long-lived complex that could act as a marker for sites of DNA damage, directing assembly of subsequent DNA repair factors. These results provide a framework for considering the kinetics of transcription-coupled repair in vivo, and open the way to reconstruction of complete DNA repair pathways at single-molecule resolution.
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Which proteins act as factors that promote transcription-coupled repair in bacteria?
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Mfd remains bound to the DNA in a long-lived complex that could act as a marker for sites of DNA damage, directing assembly of subsequent DNA repair factors.
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Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths.
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What is the Strelka workflow?
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For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing.
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Hyperprolactinaemia is one of the most common endocrinological disorder at women at the reproductive age. Prolactin is produced by the anterior lobe of the pituitary.The main role of prolactin is associated with mamotrophic action and lactogenesis. Hyperprolactinaemia causes several symptoms such as menstrual disorders, infertility, decrease of sexual function, galactorrhea in women and gynecomasty, impotence and decrease of semen quality in men. Recent studies have presented prolactin as a homone involved in many metabolic processes. Long-term consequences of high prolactin serum concentration are related to higher risk of cardiovascular system disease, disturbances in lipid profile and immunological system. Hyperprolactiaemia causes decrease of bone mass density (BMD). High serum prolactin levels lead to increase of the risk of osteopenia or/and osteoporosis. Decrease of BMD results from hypoestrogenism induced by hyperprolactinaemia and also by the direct negative influence of prolactin on bone. Hyperprolactinaemia related to prolactinoma significantly (more than functional hyperprolactiaemia) increases the risk of osteopenia, osteoporosis and bone fractures. Important group of patients threatened by osteoporosis and bone fracture is constituted by women which use antipsychotic drugs (which induce hyperprolactinaemia). Hyperprolactinaemia diagnosed in patients should be treated as soon as possible. Hyperprolactinaemic patients should be diagnosed in the direction of osteopenia and osteoporosis. When diagnosis is confirmed proper treatment is indicated.
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Does prolactinoma increase osteoporosis risk?
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Hyperprolactinaemia related to prolactinoma significantly (more than functional hyperprolactiaemia) increases the risk of osteopenia, osteoporosis and bone fractures.
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A Morel-Lavallée lesion is a post-traumatic soft tissue degloving injury which presents as a haemolymphatic mass or collection. Morel-Lavallée lesions are the result of direct trauma or shearing forces abruptly separating skin and subcutaneous tissue from underlying fascia causing disruption of perforating vessels and nerves, creating a potential space that may fill with blood, lymph and debris forming a collection. Morel-Lavallée lesions usually occur adjacent to osseous protuberances, most commonly along the greater trochanter. Early diagnosis and management is essential to prevent complications. We present this pictorial review to highlight the imaging characteristics of Morel-Lavallée lesions across imaging modalities to improve recognition, early diagnosis and management.
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What is Morel–Lavallée lesion?
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Morel-Lavallée lesions are the result of direct trauma or shearing forces abruptly separating skin and subcutaneous tissue from underlying fascia causing disruption of perforating vessels and nerves, creating a potential space that may fill with blood, lymph and debris forming a collection.
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Passive anti-beta-amyloid (Aß) immunotherapy has been shown to clear brain Aß deposits. Results from phase III clinical trials in mild-to-moderate Alzheimer's disease (AD) patients with two monoclonal antibodies bapineuzumab and solanezumab and intravenous immunoglobulin have been disappointing. Subsequent analysis of pooled data from both phase III trials with solanezumab showed a reduction in cognitive decline in patients with mild AD. Solanezumab and new monoclonal antibodies are being tested in patients with prodromal and preclinical AD in search for a disease-modifying treatment.
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Is Solanezumab effective for Alzheimer's Disease?
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Results from phase III clinical trials in mild-to-moderate Alzheimer's disease (AD) patients with two monoclonal antibodies bapineuzumab and solanezumab and intravenous immunoglobulin have been disappointing.
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Plants synthesize S-methylmethionine (SMM) from S-adenosylmethionine (AdoMet), and methionine (Met) by a unique reaction and, like other organisms, use SMM as a methyl donor for Met synthesis from homocysteine (Hcy). These reactions comprise the SMM cycle. Two Arabidopsis cDNAs specifying enzymes that mediate the SMM --> Met reaction (SMM:Hcy S-methyltransferase, HMT) were identified by homology and authenticated by complementing an Escherichia coli yagD mutant and by detecting HMT activity in complemented cells. Gel blot analyses indicate that these enzymes, AtHMT-1 and -2, are encoded by single copy genes. The deduced polypeptides are similar in size (36 kDa), share a zinc-binding motif, lack obvious targeting sequences, and are 55% identical to each other. The recombinant enzymes exist as monomers. AtHMT-1 and -2 both utilize l-SMM or (S,S)-AdoMet as a methyl donor in vitro and have higher affinities for SMM. Both enzymes also use either methyl donor in vivo because both restore the ability to utilize AdoMet or SMM to a yeast HMT mutant. However, AtHMT-1 is strongly inhibited by Met, whereas AtHMT-2 is not, a difference that could be crucial to the control of flux through the HMT reaction and the SMM cycle. Plant HMT is known to transfer the pro-R methyl group of SMM. This enabled us to use recombinant AtHMT-1 to establish that the other enzyme of the SMM cycle, AdoMet:Met S-methyltransferase, introduces the pro-S methyl group. These opposing stereoselectivities suggest a way to measure in vivo flux through the SMM cycle.
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Which is the methyl donor of histone methyltransferases?
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AtHMT-1 and -2 both utilize l-SMM or (S,S)-AdoMet as a methyl donor in vitro and have higher affinities for SMM.
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The extracellular matrix comprises a network of macromolecules such as collagens, proteoglycans and glycoproteins. VWA1 (von Willebrand factor A domain containing 1) encodes a component of the extracellular matrix that interacts with perlecan/collagen VI, appears to be involved in stabilizing extracellular matrix structures, and demonstrates high expression levels in tibial nerve. Vwa1-deficient mice manifest with abnormal peripheral nerve structure/function; however, VWA1 variants have not previously been associated with human disease. By interrogating the genome sequences of 74 180 individuals from the 100K Genomes Project in combination with international gene-matching efforts and targeted sequencing, we identified 17 individuals from 15 families with an autosomal-recessive, non-length dependent, hereditary motor neuropathy and rare biallelic variants in VWA1. A single disease-associated allele p.(G25Rfs*74), a 10-bp repeat expansion, was observed in 14/15 families and was homozygous in 10/15. Given an allele frequency in European populations approaching 1/1000, the seven unrelated homozygote individuals ascertained from the 100K Genomes Project represents a substantial enrichment above expected. Haplotype analysis identified a shared 220 kb region suggesting that this founder mutation arose >7000 years ago. A wide age-range of patients (6-83 years) helped delineate the clinical phenotype over time. The commonest disease presentation in the cohort was an early-onset (mean 2.0 ± 1.4 years) non-length-dependent axonal hereditary motor neuropathy, confirmed on electrophysiology, which will have to be differentiated from other predominantly or pure motor neuropathies and neuronopathies. Because of slow disease progression, ambulation was largely preserved. Neurophysiology, muscle histopathology, and muscle MRI findings typically revealed clear neurogenic changes with single isolated cases displaying additional myopathic process. We speculate that a few findings of myopathic changes might be secondary to chronic denervation rather than indicating an additional myopathic disease process. Duplex reverse transcription polymerase chain reaction and immunoblotting using patient fibroblasts revealed that the founder allele results in partial nonsense mediated decay and an absence of detectable protein. CRISPR and morpholino vwa1 modelling in zebrafish demonstrated reductions in motor neuron axonal growth, synaptic formation in the skeletal muscles and locomotive behaviour. In summary, we estimate that biallelic variants in VWA1 may be responsible for up to 1% of unexplained hereditary motor neuropathy cases in Europeans. The detailed clinical characterization provided here will facilitate targeted testing on suitable patient cohorts. This novel disease gene may have previously evaded detection because of high GC content, consequential low coverage and computational difficulties associated with robustly detecting repeat-expansions. Reviewing previously unsolved exomes using lower QC filters may generate further diagnoses.
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Which disease is caused by repeat expansion in VWA1?
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In summary, we estimate that biallelic variants in VWA1 may be responsible for up to 1% of unexplained hereditary motor neuropathy cases in Europeans. The detailed clinical characterization provided here will facilitate targeted testing on suitable patient cohorts. This novel disease gene may have previously evaded detection because of high GC content, consequential low coverage and computational difficulties associated with robustly detecting repeat-expansions. Reviewing previously unsolved exomes using lower QC filters may generate further diagnoses.
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It is well established that cancer-associated epigenetic repression occurs concomitant with CpG island hypermethylation and loss of nucleosomes at promoters, but the role of nucleosome occupancy and epigenetic reprogramming at distal regulatory elements in cancer is still poorly understood. Here, we evaluate the scope of global epigenetic alterations at enhancers and insulator elements in prostate and breast cancer cells using simultaneous genome-wide mapping of DNA methylation and nucleosome occupancy (NOMe-seq). We find that the genomic location of nucleosome-depleted regions (NDRs) is mostly cell type specific and preferentially found at enhancers in normal cells. In cancer cells, however, we observe a global reconfiguration of NDRs at distal regulatory elements coupled with a substantial reorganization of the cancer methylome. Aberrant acquisition of nucleosomes at enhancer-associated NDRs is associated with hypermethylation and epigenetic silencing marks, and conversely, loss of nucleosomes with demethylation and epigenetic activation. Remarkably, we show that nucleosomes remain strongly organized and phased at many facultative distal regulatory elements, even in the absence of a NDR as an anchor. Finally, we find that key transcription factor (TF) binding sites also show extensive peripheral nucleosome phasing, suggesting the potential for TFs to organize NDRs genome-wide and contribute to deregulation of cancer epigenomes. Together, our findings suggest that "decommissioning" of NDRs and TFs at distal regulatory elements in cancer cells is accompanied by DNA hypermethylation susceptibility of enhancers and insulator elements, which in turn may contribute to an altered genome-wide architecture and epigenetic deregulation in malignancy.
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What is measured through the NOMe-Seq methodology?
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Here, we evaluate the scope of global epigenetic alterations at enhancers and insulator elements in prostate and breast cancer cells using simultaneous genome-wide mapping of DNA methylation and nucleosome occupancy (NOMe-seq).
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Mutations in the TRIM8 gene have been described in patients with severe developmental delay, intellectual disability and epilepsy. Only six patients have been described to date. All the previous mutations were truncating variants clustered in the C-terminus of the protein. A previous patient with TRIM8-related epileptic encephalopathy was reported to have nephrotic syndrome. Here we describe the clinical, radiological and histological features of an 8-year-old male patient with a TRIM8 mutation who, in contrast to previous patients, had only mild intellectual disability and well-controlled epilepsy. The patient was found to have proteinuria at 2 years of age. Renal biopsy findings were suggestive of focal segmental glomerulosclerosis. His kidney function declined and peritoneal dialysis was started at 5 years of age. He underwent renal transplant at 7 years of age. Trio-based whole genome sequencing identified a novel de novo heterozygous frameshift mutation in TRIM8 (NM_030912.2) c.1198_1220del, p.(Tyr400ArgfsTer2). This patient is further evidence that TRIM8 mutations cause a syndrome with both neurological and renal features. Our findings suggest the spectrum of TRIM8-related disease may be wider than previously thought with the possibility of milder neurodevelopmental problems and/or a more severe, progressive renal phenotype. We highlight the need for proteinuria screening in patients with TRIM8 mutations.
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Which conditions are manifested by TRIM8 mutations?
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Mutations in the TRIM8 gene have been described in patients with severe developmental delay, intellectual disability and epilepsy. Only six patients have been described to date. All the previous mutations were truncating variants clustered in the C-terminus of the protein. A previous patient with TRIM8-related epileptic encephalopathy was reported to have nephrotic syndrome. Here we describe the clinical, radiological and histological features of an 8-year-old male patient with a TRIM8 mutation who, in contrast to previous patients, had only mild intellectual disability and well-controlled epilepsy. The patient was found to have proteinuria at 2 years of age. Renal biopsy findings were suggestive of focal segmental glomerulosclerosis. His kidney function declined and peritoneal dialysis was started at 5 years of age. He underwent renal transplant at 7 years of age. Trio-based whole genome sequencing identified a novel de novo heterozygous frameshift mutation in TRIM8 (NM_030912.2) c.1198_1220del, p.(Tyr400ArgfsTer2). This patient is further evidence that TRIM8 mutations cause a syndrome with both neurological and renal features. Our findings suggest the spectrum of TRIM8-related disease may be wider than previously thought with the possibility of milder neurodevelopmental problems and/or a more severe, progressive renal phenotype. We highlight the need for proteinuria screening in patients with TRIM8 mutations.
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Cardiomyopathy is a consistent feature of diabetic myocardium as well as in prolonged alcohol consumption. Diabetes-induced myocardial dysfunction has been attributed, in part, to calcium overload within individual myocytes. The present study compares the effectiveness of the calcium channel blocker nifedipine (dihydropyridine-type) with verapamil (phenylalkylamine-type) in reversing myocardial dysfunction and diminishing the negative inotropic effect of ethanol on diabetic rat myocardium. Wistar rats were made diabetic with streptozotocin (55 mg/kg, i.v.) and isolated electrically stimulated papillary muscles were studied under isometric conditions in the absence and presence of clinically relevant concentrations of ethanol (80-240 mg/dl, i e., 17.4-52.1 mM). Subgroups of diabetic and normal animals received daily injections of verapamil or nifedipine 2 weeks after induction of diabetes for 8 weeks. Untreated diabetic animals exhibited hyperglycemia, hyperlipidemia, reduced growth, cardiomegaly, and hepatomegaly. Compared to verapamil chronic nifedipine treatment normalized or reversed the effects of diabetes on myocardial mechanical function. The negative inotropic effect of ethanol was attenuated only in muscles from verapamil-treated diabetic animals. Thus, chronic nifedipine treatment may be more effective than verapamil in reducing hyperglycemia, attenuating both cardiac and liver enlargement, and restoring myocardial mechanical function, in experimental diabetes. However, chronic verapamil therapy is more effective in diminishing the negative inotropic effect of ethanol on diabetic myocardium. These findings may have clinical significance among diabetic patients who consume alcoholic beverages while receiving long-term calcium blocker therapy.
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Is calcium overload involved in the development of diabetic cardiomyopathy?
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Diabetes-induced myocardial dysfunction has been attributed, in part, to calcium overload within individual myocytes.
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The purpose of this study was to evaluate the antipyretic action of tolfenamic acid, as well as its possible adverse reactions, especially in children with severe or partial form of glucose-6-phosphate dehydrogenase (G6PD) deficiency. In the study 55 febrile children were included, whose mean age was +/- SD 3.5 +/- 3.3 years, range 0.5-15. Ten of them had severe or partial form of G6PD deficiency. Fifty-three of the patients responded with a decrease of temperature which lasted at least 6 hours, though in 2 of them the temperature decrease lasted less than 6 hours. The tolerance of the drug was good and no side-effects were noted. None of the patients with or without G6PD deficiency showed symptoms, signs, or laboratory findings indicating hemolysis before administration of the drug and 4 days thereafter. In conclusion, tolfenamic acid is a strong antipyretic agent with excellent tolerance and high safety in children.
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Which are the symptoms of glucose-6-phosphate dehydrogenase (G6PD) deficiency?
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None of the patients with or without G6PD deficiency showed symptoms, signs, or laboratory findings indicating hemolysis before administration of the drug and 4 days thereafter.
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Beneficial health effects have recently been claimed for pomegranate juice. In vitro and in vivo studies have demonstrated its anti-atherosclerotic capacity, chemoprevention and chemotherapy of prostate cancer, and antiproliferative, apoptotic, and antioxidant activity, among others. On the other hand, there is a complex interplay between tumor initiation, promotion, and progression and xenobiotic biotranformation. This led us to investigate the effect of pomegranate juice consumption on cytochrome P450 (CYP) activity and expression. For this purpose, male mice consumed this fruit juice for 4 weeks, and pentobarbital-induced sleeping time and total hepatic CYP content, activity, and expression were evaluated. Moreover, the activity of CYP isoform 2E1 and expression of the main CYP isoforms, namely, CYP1A1/2, CYP2E1, and CYP3A, were also assessed. It was found that pomegranate juice consumption decreased total hepatic CYP content as well as the expression of CYP1A2 and CYP3A. Prevention of procarcinogen activation through CYP activity/expression inhibition may be involved in pomegranate juice's effect on tumor initiation, promotion, and progression.
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Which CYP genes' expression is decreased at the in vivo level following pomegranate juice consumption?
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It was found that pomegranate juice consumption decreased total hepatic CYP content as well as the expression of CYP1A2 and CYP3A.
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Parkinson's disease is typically treated with oral dopamine replacement therapies. However, long-term use is complicated by motor fluctuations from intermittent stimulation of dopamine receptors and off-target effects. ProSavin, a lentiviral vector based gene therapy that delivers local and continuous dopamine, was previously shown to be well tolerated in a Phase I/II first-in-human study, with significant improvements in motor behavior from baseline at 1 year. Here, patients with Parkinson's disease from the open-label trial were followed up in the long term to assess the safety and efficacy of ProSavin after bilateral injection into the putamen. Fifteen patients who were previously treated with ProSavin have been followed for up to 5 years, with some having been seen for 8 years. Eight patients received deep brain stimulation at different time points, and their subsequent assessments continued to assess safety. Ninety-six drug-related adverse events were reported (87 mild, 6 moderate, 3 severe) of which more than half occurred in the first year. The most common drug-related events were dyskinesias (33 events, 11 patients) and on-off phenomena (22 events, 11 patients). A significant improvement in the defined "off" Unified Parkinson's Disease Rating Scale part III motor scores, compared to baseline, was seen at 2 years (mean score 29 · 2 vs. 38 · 4, n = 14, p < 0.05) and at 4 years in 8/15 patients. ProSavin continued to be safe and well tolerated in patients with Parkinson's disease. Moderate improvements in motor behavior over baseline continued to be reported in the majority of patients who could still be evaluated up to 5 years of follow-up.
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What is ProSavin?
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ProSavin, a lentiviral vector based gene therapy that delivers local and continuous dopamine, was previously shown to be well tolerated in a Phase I/II first-in-human study, with significant improvements in motor behavior from baseline at 1 year.
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Visualizations of biomolecular structures empower us to gain insights into biological functions, generate testable hypotheses, and communicate biological concepts. Typical visualizations (such as ball and stick) primarily depict covalent bonds. In contrast, non-covalent contacts between atoms, which govern normal physiology, pathogenesis, and drug action, are seldom visualized. We present the Protein Contacts Atlas, an interactive resource of non-covalent contacts from over 100,000 PDB crystal structures. We developed multiple representations for visualization and analysis of non-covalent contacts at different scales of organization: atoms, residues, secondary structure, subunits, and entire complexes. The Protein Contacts Atlas enables researchers from different disciplines to investigate diverse questions in the framework of non-covalent contacts, including the interpretation of allostery, disease mutations and polymorphisms, by exploring individual subunits, interfaces, and protein-ligand contacts and by mapping external information. The Protein Contacts Atlas is available at http://www.mrc-lmb.cam.ac.uk/pca/ and also through PDBe.
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Which tool has been developed for visualization of non-covalent contacts?
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We present the Protein Contacts Atlas, an interactive resource of non-covalent contacts from over 100,000 PDB crystal structures.
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The goal of this work was to extend a mathematical, multiscale systems model of bone function, remodeling, and health in order to explore hypotheses related to therapeutic modulation of sclerostin and quantitatively describe purported osteocyte activity within bone remodeling events. A pharmacokinetic model with first-order absorption and dual elimination pathways was used to describe the kinetics of romosozumab, a monoclonal antibody (mAb) against sclerostin. To describe total circulating sclerostin, an extended indirect response model of inhibition of offset was developed. These models were subsequently linked to the systems model, with sclerostin signaling changes in resorption and formation through established osteocyte-mediated mechanisms. The model proposes relative contributions of the osteocyte to the RANKL pool, a major player in feedback signaling, and is used to explore hypotheses surrounding attenuation of anabolic activity after multiple doses of sclerostin mAbs, a phenomenon whose mechanism is poorly understood.
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Describe mechanism of action of Romosozumab.
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A pharmacokinetic model with first-order absorption and dual elimination pathways was used to describe the kinetics of romosozumab, a monoclonal antibody (mAb) against sclerostin.
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Acute and late onset movement disorders frequently complicate the treatment of psychosis with typical neuroleptic drugs like haloperidol, but not with atypical neuroleptic drugs like clozapine. Although the neural mechanisms underlying neuroleptic-induced movement disorders remain unknown, alterations in basal ganglia function are likely involved. A potential role for the endogenous opiate peptides in neuroleptic-induced movement disorders is suggested by the immunocytochemical localization of met5-enkephalin (ME) in the striatopallidal projection pathway, and by the increased levels of ME measured by radioimmunoassay in the rat caudate-putamen nuclei (CPN) following haloperidol treatment. We sought to determine whether met5-enkephalin-like immunoreactivity (MELI) in terminal fields within globus pallidus and in perikarya in CPN was differentially altered in rats chronically treated with haloperidol or clozapine. Acrolein-fixed forebrain sections were collected from cohorts of adult rats receiving 21-day oral administration of haloperidol, clozapine, or water. Sections from the three treatment groups were collectively processed for immunocytochemical labeling using varying dilutions of ME antiserum and the avidin-biotin peroxidase method. In globus pallidus, densitometry measures revealed significantly increased levels of immunoperoxidase labeling for ME in haloperidol-treated, but not in clozapine-treated animals. In CPN, optical densitometry as well as cell counting measurements also showed a significant increase in MELI only in the haloperidol-treated group. These results support the concept that alterations in endogenous opiate peptides in basal ganglia may contribute to movement disorders seen in patients receiving typical neuroleptic drugs.(ABSTRACT TRUNCATED AT 250 WORDS)
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For the treatment of which conditions can atypical neuroleptic drugs be used?
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Acute and late onset movement disorders frequently complicate the treatment of psychosis with typical neuroleptic drugs like haloperidol, but not with atypical neuroleptic drugs like clozapine.
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Excitatory amino acid transporters (EAATs) are the primary regulators of extracellular glutamate concentrations in the central nervous system. Their dysfunction may contribute to several neurological diseases. To date, five distinct mammalian glutamate transporters have been cloned. In brain, EAAC1 (excitatory amino acid carrier 1) is the primary neuronal glutamate transporter, localized on the perisynaptic membranes that are near release sites. Despite its potential importance in synaptic actions, little is known concerning the regulation of EAAC1 trafficking from the endoplasmic reticulum (ER) to the cell surface. Previously, we identified an EAAC1-associated protein, GTRAP3-18, an ER protein that prevents ER exit of EAAC1 when induced. Here we show that RTN2B, a member of the reticulon protein family that mainly localizes in the ER and ER exit sites interacts with EAAC1 and GTRAP3-18. EAAC1 and GTRAP3-18 bind to different regions of RTN2B. Each protein can separately and independently form complexes with EAAC1. RTN2B enhances ER exit and the cell surface composition of EAAC1 in heterologous cells. Expression of short interfering RNA-mediated knockdown of RTN2B decreases the EAAC1 protein level in neurons. Overall, our results suggest that RTN2B functions as a positive regulator in the delivery of EAAC1 from the ER to the cell surface. These studies indicate that transporter exit from the ER controlled by the interaction with its ER binding partner represents a critical regulatory step in glutamate transporter trafficking to the cell surface.
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Which are the human glutamate transporters?
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Here we show that RTN2B, a member of the reticulon protein family that mainly localizes in the ER and ER exit sites interacts with EAAC1 and GTRAP3-18
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The study aimed to examine the tolerability of the combination of radiotherapy and tamoxifen and the effect on median and event free survival as well as collecting data on the use of steroids in this population. 31 patients with diffuse intrinsic pontine glioma, diagnosed on clinical and radiological criteria, were treated with high-dose oral tamoxifen (120 mg/m(2)/day) given concomitantly with standard dose radiotherapy (54 Gy in 1.8 Gy fractions over 6 weeks). Results Tamoxifen was well tolerated with no grade 3 or 4 CTC toxicity reported. At 1 year, the progression free and event free survival were 3.2% (95% CI: 0.2-14.1%), and at 6 months 19.4% (CI: 7.9% to 34.6%). The overall survival at 1 year was 16.1% (CI: 5.9-30.9%) with median survival 6.32 months. In this study, in which tamoxifen was used in conjunction with radiotherapy, progression free survival was shown to be less good when compared with historical data HR = 3.1 (CI: 1.7-5.7). There was no significant reduction in overall survival. The addition of high-dose tamoxifen, although well tolerated, confers no clinical benefit to patients treated with diffuse intrinsic pontine glioma treated with standard radiotherapy.
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Was tamoxifen tested for treatment of glioma patients?
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The addition of high-dose tamoxifen, although well tolerated, confers no clinical benefit to patients treated with diffuse intrinsic pontine glioma treated with standard radiotherapy.
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Chronic alcohol abuse depresses the nervous system and, upon cessation, rebound hyperexcitability can result in withdrawal seizure. Withdrawal symptoms, including seizures, may drive individuals to relapse, thus representing a significant barrier to recovery. Our lab previously identified an upregulation of the thalamic T-type calcium (T channel) isoform CaV3.2 as a potential contributor to the generation and propagation of seizures in a model of withdrawal. In the present study, we examined whether ethosuximide (ETX), a T-channel antagonist, could decrease the severity of ethanol withdrawal seizures by evaluating electrographical and behavioral correlates of seizure activity. DBA/2J mice were exposed to an intermittent ethanol exposure paradigm. Mice were treated with saline or ETX in each withdrawal period, and cortical EEG activity was recorded to determine seizure severity. We observed a progression in seizure activity with each successive withdrawal period. Treatment with ETX reduced ethanol withdrawal-induced spike and wave discharges (SWDs), in terms of absolute number, duration of events, and contribution to EEG power in the 6-10 Hz frequency range. We also evaluated the effects of ETX on handling-induced convulsions. Overall, we observed a decrease in handling-induced convulsion severity in mice treated with ETX. Our findings suggest that ETX may be a useful pharmacological agent for studies of alcohol withdrawal and treatment of resulting seizures.
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Which calcium channels does ethosuximide target?
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In the present study, we examined whether ethosuximide (ETX), a T-channel antagonist, could decrease the severity of ethanol withdrawal seizures by evaluating electrographical and behavioral correlates of seizure activity.
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In eukaryotic cells, there is evidence for functional coupling between transcription and processing of pre-mRNAs. To better understand this coupling, we performed a high-resolution kinetic analysis of transcription and splicing in budding yeast. This revealed that shortly after induction of transcription, RNA polymerase accumulates transiently around the 3' end of the intron on two reporter genes. This apparent transcriptional pause coincides with splicing factor recruitment and with the first detection of spliced mRNA and is repeated periodically thereafter. Pausing requires productive splicing, as it is lost upon mutation of the intron and restored by suppressing the splicing defect. The carboxy-terminal domain of the paused polymerase large subunit is hyperphosphorylated on serine 5, and phosphorylation of serine 2 is first detected here. Phosphorylated polymerase also accumulates around the 3' splice sites of constitutively expressed, endogenous yeast genes. We propose that transcriptional pausing is imposed by a checkpoint associated with cotranscriptional splicing.
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Which is the phosphorylated residue in the promoter paused form of RNA polymerase II?
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The carboxy-terminal domain of the paused polymerase large subunit is hyperphosphorylated on serine 5, and phosphorylation of serine 2 is first detected here
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Meningitis and sepsis caused by serogroup B meningococcus are two severe diseases that still cause significant mortality. To date there is no universal vaccine that prevents these diseases. In this work, five antigens discovered by reverse vaccinology were expressed in a form suitable for large-scale manufacturing and formulated with adjuvants suitable for human use. The vaccine adjuvanted by aluminum hydroxide induced bactericidal antibodies in mice against 78% of a panel of 85 meningococcal strains representative of the global population diversity. The strain coverage could be increased to 90% and above by the addition of CpG oligonucleotides or by using MF59 as adjuvant. The vaccine has the potential to conquer one of the most devastating diseases of childhood.
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List diseases that are caused by the Meningococcus B?
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Meningitis and sepsis caused by serogroup B meningococcus are two severe diseases that still cause significant mortality.
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This paper reports the efficacy and tolerability of the nicotinic channel modulator TC-5214 (dexmecamylamine) as adjunct therapy for patients with major depressive disorder who have an inadequate response to initial antidepressant treatment in 2 Phase III studies. These double-blind, placebo-controlled studies (NCT01157078, D4130C00002 [Study 002] conducted in the US and India; NCT01180400, D4130C00003 [Study 003] conducted in Europe) comprised 8 weeks of open-label antidepressant treatment followed by 8 weeks of active treatment during which patients were randomized to flexibly-dosed TC-5214 1-4 mg twice daily (BID) or placebo as an adjunct to ongoing therapy with SSRI/SNRI. The primary efficacy endpoint in both studies was change in Montgomery Åsberg Depression Rating Scale (MADRS) total score from randomization (week 8) to treatment end (week 16). Secondary endpoints included change in Sheehan Disability Scale and Hamilton Depression Rating Scale 17-item scores. Study 002 randomized 319 patients and Study 003 randomized 295 patients to TC-5214 or placebo. At treatment end, no significant differences were seen for change in MADRS total score with TC-5214 versus placebo. Furthermore, there were no significant differences in any of the secondary endpoints. The most commonly reported (≥ 10%) adverse events with TC-5214 in these studies were constipation and headache. In these 2 flexibly-dosed studies, no specific therapeutic effects were observed for TC-5214 (1-4 mg BID) adjunct to antidepressant in the primary endpoint or any secondary endpoint; however, TC-5214 was generally well tolerated. In conclusion, no antidepressant effect of TC-5214 was observed in these studies.
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Is Dexmecamylamine effective for depression?
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At treatment end, no significant differences were seen for change in MADRS total score with TC-5214 versus placebo.
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Lipid droplets (LD) are spherical cellular inclusion devoted to lipids storage. It is well known that excessive accumulation of lipids leads to several human worldwide diseases like obesity, type 2 diabetes, hepatic steatosis and atherosclerosis. LDs' size range from fraction to one hundred of micrometers in adipocytes and is related to the lipid content, but their growth is still a puzzling question. It has been suggested that LDs can grow in size due to the fusion process by which a larger LD is obtained by the merging of two smaller LDs, but these events seems to be rare and difficult to be observed. Many other processes are thought to be involved in the number and growth of LDs, like the de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets. Moreover the number and size of LDs are influenced by the catabolism and the absorption or interaction with other organelles. The comprehension of these processes could help in the confinement of the pathologies related to lipid accumulation. In this study the LDs' size distribution, number and the total volume of immature (n=12), mature (n=12, 10-days differentiated) and lipolytic (n=12) 3T3-L1 adipocytes were considered. More than 11,000 LDs were measured in the 36 cells after Oil Red O staining. In a previous work Monte Carlo simulations were used to mimic the fusion process alone between LDs. We found that, considering the fusion as the only process acting on the LDs, the size distribution in mature adipocytes can be obtained with numerical simulation starting from the size distribution in immature cells provided a very high rate of fusion events. In this paper Monte Carlo simulations were developed to mimic the interaction between LDs taking into account many other processes in addition to fusion (de novo formation and the growth through additional neutral lipid deposition in pre-existing droplets) in order to reproduce the LDs growth and we also simulated the catabolism (fission and the decrease through neutral lipid exit from pre-existing droplets) to reproduce their size reduction observed in lipolytic conditions. The results suggest that each single process, considered alone, can not be considered the only responsible for the size variation observed, but more than one of them, playing together, can quite well reproduce the experimental data.
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What is the lipid droplet used for in the cell?
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Lipid droplets (LD) are spherical cellular inclusion devoted to lipids storage.
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Brain tumors are the most common solid tumors in children. Pediatric high-grade glioma (HGG) accounts for ∼8-12 % of these brain tumors and is a devastating disease as 70-90 % of patients die within 2 years of diagnosis. The failure to advance therapy for these children over the last 30 years is largely due to limited knowledge of the molecular basis for these tumors and a lack of disease models. Recently, sequencing of tumor cells revealed that histone H3 is frequently mutated in pediatric HGG, with up to 78 % of diffuse intrinsic pontine gliomas (DIPGs) carrying K27M and 36 % of non-brainstem gliomas carrying either K27M or G34R/V mutations. Although mutations in many chromatin modifiers have been identified in cancer, this was the first demonstration that histone mutations may be drivers of disease. Subsequent studies have identified high-frequency mutation of histone H3 to K36M in chondroblastomas and to G34W/L in giant cell tumors of bone, which are diseases of adolescents and young adults. Interestingly, the G34 mutations, the K36M mutations, and the majority of K27M mutations occur in genes encoding the replacement histone H3.3. Here, we review the peculiar characteristics of histone H3.3 and use this information as a backdrop to highlight current thinking about how the identified mutations may contribute to disease development.
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Which driver mutations have been identified for Diffuse Intrinsic Pontine Glioma (DIPG)?
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Recently, sequencing of tumor cells revealed that histone H3 is frequently mutated in pediatric HGG, with up to 78 % of diffuse intrinsic pontine gliomas (DIPGs) carrying K27M and 36 % of non-brainstem gliomas carrying either K27M or G34R/V mutations.
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This short paper demonstrates that the Finkelstein's test in De Quervain's tenosynovitis is based on an incorrect assumption. The correct basis for a pathognomic manoeuvre in De Quervain is the provocation of tendons attrition of the first wrist dorsal compartment against their pulley which elicits pain. The Brunelli's test induces this friction and pain by asking the patient to hardly adduct the thumb with the wrist in radial deviation.
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Which disease is diagnosed using the Finkelstein's test?
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This short paper demonstrates that the Finkelstein's test in De Quervain's tenosynovitis is based on an incorrect assumption.
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Ubrogepant (Ubrelvy™) is an orally administered, small molecule, highly-selective, calcitonin gene-related peptide (CGRP) antagonist that was developed by Allergan under license to Merck & Co. as an acute treatment for migraine. In December 2019, ubrogepant received its first global approval in the USA for the acute treatment of migraine (± aura) in adults. This article summarizes the milestones in the development of ubrogepant leading to its first global approval for the acute treatment of migraine (± aura) in adults.
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Please list 3 small molecule CGRP-Receptor antagonists for migraine
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This article summarizes the milestones in the development of ubrogepant leading to its first global approval for the acute treatment of migraine (± aura) in adults.
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Chronic wasting disease (CWD) in cervids is one of the transmissible spongiform encephalopathies ; however, its risk to humans is still obscure. An increase in number of diseased deer in North America has raised concerns regarding the CWD risk to humans. We demonstrated that the con-firmatory procedures and the commercial diagnostic kits for bovine spongiform encephalopathy (BSE) can be adopted for the diagnosis of CWD. No CWD case was confirmed in the surveillance of 558 cervids that were examined between 2003 and 2006 in Japan.
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What is Chronic Wasting Disease (CWD) in deer?
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Chronic wasting disease (CWD) in cervids is one of the transmissible spongiform encephalopathies
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Melioidosis is a disease of humans caused by opportunistic infection with the soil and water bacterium Burkholderia pseudomallei. Melioidosis can manifest as an acute, overwhelming infection or as a chronic, recurrent infection. At present, it is not clear where B. pseudomallei resides in the mammalian host during the chronic, recurrent phase of infection. To address this question, we developed a mouse low-dose mucosal challenge model of chronic B. pseudomallei infection and investigated sites of bacterial persistence over 60 days. Sensitive culture techniques and selective media were used to quantitate bacterial burden in major organs, including the gastrointestinal (GI) tract. We found that the GI tract was the primary site of bacterial persistence during the chronic infection phase, and was the only site from which the organism could be consistently cultured during a 60-day infection period. The organism could be repeatedly recovered from all levels of the GI tract, and chronic infection was accompanied by sustained low-level fecal shedding. The stomach was identified as the primary site of GI colonization as determined by fluorescent in situ hybridization. Organisms in the stomach were associated with the gastric mucosal surface, and the propensity to colonize the gastric mucosa was observed with 4 different B. pseudomallei isolates. In contrast, B. pseudomallei organisms were present at low numbers within luminal contents in the small and large intestine and cecum relative to the stomach. Notably, inflammatory lesions were not detected in any GI tissue examined in chronically-infected mice. Only low-dose oral or intranasal inoculation led to GI colonization and development of chronic infection of the spleen and liver. Thus, we concluded that in a mouse model of melioidosis B. pseudomallei preferentially colonizes the stomach following oral inoculation, and that the chronically colonized GI tract likely serves as a reservoir for dissemination of infection to extra-intestinal sites.
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Is Melioidosis caused by the bacterium Burkholderia pseudomallei?
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Melioidosis is a disease of humans caused by opportunistic infection with the soil and water bacterium Burkholderia pseudomallei.
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Psoriasis is a chronic, genetic, inflammatory skin disease affecting approximately 2% of the population worldwide. Over the past decade, multiple studies have shown that not only is there an association between psoriasis and psoriatic arthritis, depression, and substance abuse, but psoriasis patients also have a higher incidence of obesity, diabetes, heart disease and stroke. In addition, and more concerning, young psoriatic patients particularly those with more severe disease are at an increased mortality risk even when controlling for these factors. The systemic inflammation in psoriasis generates elevation of C-reactive protein, homocysteine, and inflammatory cytokines such as TNF-a, IL-6, IL-17, IL-20, IL-22, and IL-23, which may contribute to the overall morbidity and mortality in these patients. Within this article we will discuss the associations between psoriasis and multiple systemic health problems.
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What is the link between psoriatic arthritis and depression
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Over the past decade, multiple studies have shown that not only is there an association between psoriasis and psoriatic arthritis, depression, and substance abuse, but psoriasis patients also have a higher incidence of obesity, diabetes, heart disease and stroke.
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Mannarino, P, Matta, T, Lima, J, Simão, R, and Freitas de Salles, B. Single-Joint Exercise Results in Higher Hypertrophy of Elbow Flexors Than Multijoint Exercise. J Strength Cond Res 35(10): 2677-2681, 2021-Recent data suggest that single-joint exercises are unnecessary to maximize the resistance training (RT) results in novice to advanced individuals. However, the present literature is still inconsistent on this topic and controversy arises. The aim of this study was to compare the effects of the unilateral dumbbell row (DR) (multiple-joint) vs. unilateral biceps curl (BC) (single-joint) exercises on strength and elbow flexors muscle thickness (MT). Ten untrained men were assigned to an 8-week RT program for elbow flexors, one arm performing DR and the other performing BC in a within-subject design. After a familiarization, pretraining MT was measured using an ultrasound (US) technique, and strength was tested using 10 repetition maximum (10RM) tests. After pretesting, 8 weeks of RT (4-6 sets, 8-12 repetitions to concentric failure, 2 sessions per week) was performed. Post-testing was conducted in the same order as pretesting 48 and 72 hours after the last session. Single-joint BC exercise resulted in higher hypertrophy of elbow flexors (11.06%) than the DR (5.16%) multijoint exercise after 8 weeks of RT (p = 0.009). The 10RM improvement was higher for DR in DR-trained arm, whereas 10RM for BC was higher in BC-trained arm. The single-joint exercise resulted in higher hypertrophy of the elbow flexors than multijoint exercise after 8 weeks of RT, whereas strength improvements were greater in accordance with specificity of RT exercise. Therefore, in RT prescription for elbow flexors hypertrophy, single-joint exercises such as BC should be emphasized.
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Is resistance training usually associated with increasing muscle hypertrophy?
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Therefore, in RT prescription for elbow flexors hypertrophy, single-joint exercises such as BC should be emphasized
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The first draft of the human genome has revealed enormous variability in the global distribution of Alu repeat elements. There are regions such as the four homeobox gene clusters, which are nearly devoid of these repeats that contrast with repeat dense regions in other transcriptionally active regions of the genome. Our analysis of the completely sequenced chromosomes 21 and 22 revealed a striking bias in Alu distribution. These elements are more clustered in genes which are involved in metabolism, transport, and signaling processes. In contrast, they are significantly fewer in genes coding for information pathway components as well as structural proteins. This bias in Alu distribution is independent of the effect of Alu density of the flanking genomic region and is also not affected by the GC content of the gene and its upstream and downstream regions. The relative proportions of Alu subfamilies (Alu J, Alu S, and Alu Y) are not significantly different in genes with high Alu density belonging to the functional categories of transport, metabolism, and signaling. However, in the structural proteins and information genes, these proportions are lower than the other three categories. We suggest that Alu elements might be involved in regulatory mechanisms and are therefore differentially selected in primate genomes.
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In which genomic regions are Alu enriched?
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The relative proportions of Alu subfamilies (Alu J, Alu S, and Alu Y) are not significantly different in genes with high Alu density belonging to the functional categories of transport, metabolism, and signaling.
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Complex diseases are common genetic disorders showing familial aggregation but no typical Mendelian inheritance. Hirschsprung disease (HSCR), a developmental disorder characterized by the absence of enteric neurons in distal segments of the gut, shows a complex pattern of inheritance, with the RET protooncogene acting as a major gene and additional susceptibility loci playing minor roles. In the last years, we have identified a "protective" RET haplotype, which is underrepresented in HSCR patients with respect to controls. Here, we demonstrate that the protective effect of this haplotype is due to a variant located in the 3' untranslated region (UTR) of the RET gene, which slows down the physiological mRNA decay of the gene transcripts. Such a functional effect of this common RET variant explains the under-representation of the whole haplotype and its role as a modifying factor in HSCR pathogenesis.
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Is RET the major gene involved in Hirschsprung disease?
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Hirschsprung disease (HSCR), a developmental disorder characterized by the absence of enteric neurons in distal segments of the gut, shows a complex pattern of inheritance, with the RET protooncogene acting as a major gene and additional susceptibility loci playing minor roles.
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Mutations in alpha-glucosidase cause accumulation of glycogen in lysosomes, resulting in Pompe disease, a lysosomal storage disorder. Small molecule chaperones that bind to enzyme proteins and correct the misfolding and mistrafficking of mutant proteins have emerged as a new therapeutic approach for the lysosomal storage disorders. In addition, alpha-glucosidase is a therapeutic target for type II diabetes, and alpha-glucosidase inhibitors have been used in the clinic as alternative treatments for this disease. We have developed a new fluorogenic substrate for the alpha-glucosidase enzyme assay, resorufin alpha-d-glucopyranoside. The enzyme reaction product of this new substrate emits at a peak of 590 nm, reducing the interference from fluorescent compounds seen with the existing fluorogenic substrate, 4-methylumbelliferyl-alpha-D-glucopyranoside. Also, the enzyme kinetic assay can be carried out continuously without the addition of stop solution due to the lower pK(a) of the product of this substrate. Therefore, this new fluorogenic substrate is a useful tool for the alpha-glucosidase enzyme assay and will facilitate compound screening for the development of new therapies for Pompe disease.
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Is acid alpha-glucosidase the enzyme that causes Pompe disease when mutant?
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Mutations in alpha-glucosidase cause accumulation of glycogen in lysosomes, resulting in Pompe disease, a lysosomal storage disorder.
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Certain DNA binding proteins are thought to organize the mammalian genome into distinct 3 dimensional structures, each characteristic of a given differentiated state. Autoantibodies to 2 types of DNA binding protein complexes, the nuclear lamina and p70/p80 (Ku), were identified in sera of patients with collagen vascular diseases. The intranuclear distribution, DNA binding, and behavior during mitosis of these antigens were examined using autoimmune sera and murine monoclonal antibodies. In vivo, the antigens have different intranuclear distributions and solubility characteristics. However, both antigens appear to reversibly bind to DNA during interphase and to rapidly dissociate from DNA during mitosis. Although the binding affinity of p70/p80 to DNA is heterogeneous, the interaction between p70/p80 and DNA in vitro is stable over 2 h or more. The rapid dissociation of p70/p80 from DNA during mitosis may therefore be mediated by a modification in either chromatin structure or in the p70/p80 antigen itself. Other proteins that reversibly interact with DNA, such as the lamins and nuclear pores, may have a role in the organization of DNA into transcribable euchromatin and nontranscribable heterochromatin. Autoantibodies to these proteins, and possibly those reactive with p70/p80, or other DNA binding proteins may be useful probes for studying both chromatin organization and the causes of autoimmune diseases such as systemic lupus erythematosus.
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Do A-type lamins bind euchromatin or heterochromatin?
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Other proteins that reversibly interact with DNA, such as the lamins and nuclear pores, may have a role in the organization of DNA into transcribable euchromatin and nontranscribable heterochromatin.
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Imatinib has improved outcomes in patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (all). Minimal residual disease (mrd) is a useful tool for predicting leukemia relapse. However, there is no consensus on how to treat children with elevation of BCR-ABL transcripts but no evidence of hematologic relapse during chemotherapy combined with imatinib. Here, we report the case of a child with Ph+ all who had persistent elevation of mrd, but no evidence of hematologic relapse while receiving imatinib plus intensive chemotherapy. Dasatinib was substituted for imatinib because no suitable donor for allogeneic hematopoietic stem-cell transplantation (hsct) was available. Less-intensive chemotherapy with methotrexate and 6-mercaptopurine was administered concomitantly. No serious adverse events were encountered. With continuous dasatinib combined with chemotherapy, but no allogeneic hsct, our patient reached complete molecular remission and has been in complete molecular remission for more than 13 months. This report is the first about the long-term use of dasatinib in patients with Ph+ all and mrd elevation but hematologic remission during imatinib chemotherapy. In a similar situation, chemotherapy combined with dasatinib instead of allogeneic hsct could be considered to avoid hsct-related mortality and morbidity. Clinical trials are needed.
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Which disease is Dasatinib used to treat?
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With continuous dasatinib combined with chemotherapy, but no allogeneic hsct, our patient reached complete molecular remission and has been in complete molecular remission for more than 13 months.
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Craniosynostosis is a complex condition, characterized by the premature fusion of one of more of the cranial sutures. They can be seen individually or as part of multisystem syndromes. This review uses computed tomography (CT) with three-dimensional reconstructions to help describe some of the types and classifications of craniosynostosis, as well as describing some of the associations and the management of craniosynostosis.
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What is craniosynostosis?
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Craniosynostosis is a complex condition, characterized by the premature fusion of one of more of the cranial sutures.
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The etiology of subacute (de Quervain's) thyroiditis (SAT) is uncertain, although it probably represents a nonspecific inflammatory response by the thyroid to a variety of viruses. It has been suggested that nonimmune processes are involved in SAT patients who have negative autoantibody titers. The disease has a variable course; although it is self-limited in most cases, some patients develop transient hypothyroidism, and others do not during the recovery period. The present study was performed to evaluate the occurrence of TSH receptor antibody (TRAb), measured by RRA (TSH binding inhibitor), TRAb measured by stimulation assay (thyroid-stimulating antibody), and TRAb measured by blocking assay [TSH-blocking antibody (TSH-BAb)] activity in 68 patients with SAT who had negative autoantibody titers. The patients were divided into 2 groups: group I, 31 patients who developed hypothyroidism during the recovery period; and group II, 37 patients who remained euthyroid during recovery. Positive immunoglobulin activity occurred in about 20% of group I patients during follow-up, but in only 3% of group II patients. About 20% of group I patients developed positive TSH-BAb activity and were hypothyroid, requiring exogenous hormone therapy for 1.2-3.5 yr, whereas hypothyroidism was relatively transient in group I patients who had negative TSH-BAb activity (2-6 months). Although increased TSH-BAb activity may account for hypothyroidism in some patients with SAT, the precise mechanism for the development of transient hypothyroidism in SAT remains enigmatic.
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Are viruses involved in the etiology of human subacute thyroiditis?
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he etiology of subacute (de Quervain's) thyroiditis (SAT) is uncertain, although it probably represents a nonspecific inflammatory response by the thyroid to a variety of viruses.
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Thrombocytopenia is frequent among sick neonates. While most cases are transient, some neonates experience prolonged and severe thrombocytopenia. These infants often pose diagnostic and therapeutic challenges, and may receive large numbers of platelet transfusions. Romiplostim (ROM) is a thrombopoietin (TPO)-receptor-agonist approved for treatment of adults with chronic immune thrombocytopenia (ITP). The immature platelet fraction (IPF) is a novel measure of newly produced platelets, which could aid with the diagnostic evaluation of thrombocytopenic neonates. This study had the following two objectives: (1) compare the response of newborn and adult mice to escalating doses of ROM in vivo and (2) assess the correlation between IPF and megakaryocyte (MK) mass in newborn and adult treated and untreated mice. In the first set of studies, newborn (day 1) and adult mice received a single subcutaneous (SC) dose of ROM ranging from 0 to 300 ng/g, and platelet counts were followed every other day for 14 days. Both sets of mice responded with dose-dependent platelet and IPF increases, peaking on days 5-7 post-treatment, but neonates had a blunted response (2.1-fold compared to 4.2-fold maximal increase in platelet counts, respectively). On day 5 post-treatment with 300 ng/g ROM, MKs in the bone marrow (BM) and spleen of adult mice were significantly increased in numbers and size (p < 0.0001 for both) compared to controls. MKs in the spleen and BM (but not liver) of treated neonates also increased in number, but not in size. The immature platelet count (IPC, calculated as IPF x platelet count) was highly correlated with the MK number and size in neonatal and adult BM and spleen, but not neonatal liver. The lack of response of neonatal liver MKs was not due to a cell-intrinsic reduced responsiveness to TPO, since neonatal liver progenitors were more sensitive to murine TPO (mTPO) in vitro than adult BM progenitor. In vivo treatment of newborn mice with high mTPO doses or with higher doses of ROM (900 ng/g) resulted in peak platelet counts approaching 3-fold of controls. Taken together, our data indicate that newborn mice are less responsive to ROM than adult mice in vivo, due to a combination of likely pharmacokinetic differences and developmental differences in the response of MKs to thrombopoietic stimulation, evidenced by neonatal MKs increasing in numbers but not in size. PK/PD studies in human infants treated with ROM are warranted.
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What is romiplostim targeting?
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Romiplostim (ROM) is a thrombopoietin (TPO)-receptor-agonist approved for treatment of adults with chronic immune thrombocytopenia (ITP).
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Growth factor signaling pathways are tightly regulated by phosphorylation and include many important kinase targets of interest for drug discovery. Small molecule inhibitors of the bone morphogenetic protein (BMP) receptor kinase ALK2 (ACVR1) are needed urgently to treat the progressively debilitating musculoskeletal disease fibrodysplasia ossificans progressiva (FOP). Dorsomorphin analogues, first identified in zebrafish, remain the only BMP inhibitor chemotype reported to date. By screening an assay panel of 250 recombinant human kinases we identified a highly selective 2-aminopyridine-based inhibitor K02288 with in vitro activity against ALK2 at low nanomolar concentrations similar to the current lead compound LDN-193189. K02288 specifically inhibited the BMP-induced Smad pathway without affecting TGF-β signaling and induced dorsalization of zebrafish embryos. Comparison of the crystal structures of ALK2 with K02288 and LDN-193189 revealed additional contacts in the K02288 complex affording improved shape complementarity and identified the exposed phenol group for further optimization of pharmacokinetics. The discovery of a new chemical series provides an independent pharmacological tool to investigate BMP signaling and offers multiple opportunities for pre-clinical development.
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What genes are drug targets for Fibrodysplasia Ossificans Progressiva (FOP)?
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Dorsomorphin analogues, first identified in zebrafish, remain the only BMP inhibitor chemotype reported to date.
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Rituximab is an anti-CD20 monoclonal antibody with considerable potential in dermatology due to an increase in off-label indications. Chronic graft-versus-host disease and pemphigus vulgaris are two of the most promising indications for off-label use of rituximab. It is a generally safe alternative that should be considered when traditional therapy with corticosteroids or immunosuppressants has failed or caused significant intolerance. Currently, rituximab is only FDA-approved for treatment of follicular and diffuse large B-cell non-Hodgkin's lymphoma, rheumatoid arthritis, chronic lymphocytic leukemia, granulomatosis with polyangiitis (formerly Wegener's granulomatosis) and microscopic polyangiitis. Herein, off-label uses of rituximab and its efficacy in the treatment of cutaneous diseases are reviewed.
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List 3 indications for rituximab.
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Currently, rituximab is only FDA-approved for treatment of follicular and diffuse large B-cell non-Hodgkin's lymphoma, rheumatoid arthritis, chronic lymphocytic leukemia, granulomatosis with polyangiitis (formerly Wegener's granulomatosis) and microscopic polyangiitis.
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The natural history of non-muscle invasive bladder cancer is characterized by a high probability of recurrence and in the case of high-grade tumors, progression to muscle invasive cancer. This mandates a follow-up strategy designed to identify recurrences in the bladder early in their evolution in order to facilitate early intervention and ablation. Urine cytology is considered the gold standard urine biomarker. Although specificity exceeds 90% to 95%, its overall sensitivity ranges from 40% to 60% in expert hands and is both tumor grade and operator dependent. While cytology is an excellent test for detection of high-grade disease, the sensitivity is particularly weak for the detection of low grade tumors. This has spawned an entire field of research of in vitro diagnostic tests and cell-based assays in order to improve the diagnostic accuracy for detection of incident or recurrent disease. To date, the US Food and Drug Administration approved dipstick and immunoassays marketed as point-of-care tests. The point-of-care tests are intended for use as an adjunct to cystoscopy and cytology, and may have a role in the office evaluation of hematuria patients. Monoclonal antibody-based tests combined with cytology may improve the diagnostic accuracy and are superior to cytology alone. A recently approved cell-based assay, utilizing fluorescent in situ hybridization technology, may help resolve suspicious cytologies, and provide early and additional information about the biology of the bladder urothelium beyond that provided by cytology, a marker of disease relatively late in evolution. Novel promising markers are in various stages of clinical testing, and a panel of biomarkers may serve in the future as a feasible alternative to urine cytology and cystoscopy for the screening, detection, and follow-up of non-muscle invasive bladder cancer.
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Are there any urine biomarkers for bladder cancer diagnosis?
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Novel promising markers are in various stages of clinical testing, and a panel of biomarkers may serve in the future as a feasible alternative to urine cytology and cystoscopy for the screening, detection, and follow-up of non-muscle invasive bladder cancer.
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Bow Hunter's syndrome, also referred to as rotational occlusion of the vertebral artery, is caused by dynamic compression of a patient's dominant vertebral artery. We reported a case of successful clinical and imaging work up of Bow Hunter's Syndrome that occurred in a 79-year-old female patient. We discussed the clinical presentation, imaging findings, and subsequent management options of this rare syndrome. The gold standard for diagnosis is dynamic cerebral angiography, which allows the reproduction of symptoms with head turn greater than 30-45 degrees. Subsequent management is based on the underlying etiology causing rotational compression.
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What is the cause of Bow Hunter's syndrome?
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Bow Hunter's syndrome, also referred to as rotational occlusion of the vertebral artery, is caused by dynamic compression of a patient's dominant vertebral artery.
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Current early pregnancy screening tools to identify women at risk of developing gestational diabetes mellitus lack both specificity and sensitivity. As a result, the foetus and mother are often subjected to insult during disease progression, prior to diagnosis and treatment in later pregnancy. Metabolomics is an analytical approach, which allows for appraisal of small molecular mass compounds in a biofluid. The aim of this pilot study was to investigate the relationship between the early gestation serum metabolite profile and the subsequent development of gestational diabetes mellitus in the search for early pregnancy biomarkers and potential metabolic mechanisms. Our nested case-control study analysed maternal serum at 20 weeks' gestation, obtained from the New Zealand cohort of the Screening for Pregnancy Endpoints study. Metabolomic profiling was performed using gas chromatography coupled to mass spectrometry, and metabolites were identified using R software and an in-house mass spectral library. Statistical analysis was performed using SPSS version 21.0. Forty-eight metabolites were identified in the serum samples. Itaconic acid (P = 0.0003), with a false discovery rate of 0.012, was found to be significantly more abundant in women who subsequently developed gestational diabetes mellitus, when compared to controls with uncomplicated pregnancies. The current pilot study found that itaconic acid may have potential as a novel biomarker in early pregnancy to predict the subsequent development of gestational diabetes mellitus. However, the findings from this pilot study require validation with a larger, diverse population before translation into the clinical setting.
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When are itaconic acid levels elevated?
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taconic acid (P = 0.0003), with a false discovery rate of 0.012, was found to be significantly more abundant in women who subsequently developed gestational diabetes mellitus, when compared to controls with uncomplicated pregnancies.
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Protozoan parasites are one of the oldest living entities in this world that throughout their existence have shown excellent resilience to the odds of survival and have adapted beautifully to ever changing rigors of the environment. In view of the dynamic environment encountered by them throughout their life cycle, and in establishing pathogenesis, it is unsurprising that modulation of gene expression plays a fundamental role in their survival. In higher eukaryotes, untranslated regions (UTRs) of transcripts are one of the crucial regulators of gene expression (influencing mRNA stability and translation efficiency). Parasitic protozoan genome studies have led to the characterization (in silico, in vitro and in vivo) of a large number of their genes. Comparison of higher eukaryotic UTRs with parasitic protozoan UTRs reveals the existence of several similar and dissimilar facets of the UTRs. This review focuses on the elements of UTRs of medically important protozoan parasites and their regulatory role in gene expression. Such information may be useful to researchers in designing gene targeting strategies linked with perturbation of host-parasite relationships leading to control of specific parasites.
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Can untranslated regions (UTRs) regulate gene expression?
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In higher eukaryotes, untranslated regions (UTRs) of transcripts are one of the crucial regulators of gene expression (influencing mRNA stability and translation efficiency).
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Liver cancer (hepatocellular carcinoma, HCC) is a major malignancy worldwide. Etiologically, hepatocarcinogenesis is closely associated with HBV and HCV infections; however, its underlying molecular mechanism is not completely understood. MicroRNAs are a class of small non-coding RNAs that negatively regulate gene expression by interacting with the 3'UTR of protein-coding mRNA. MicroRNAs are implicated in nearly all major biological and cellular events, and recent findings further link microRNA deregulation to human carcinogenesis. In this review, we will focus on the aberrant expression of miRNAs in liver cancer and the pathological implications and molecular functions of some well-characterized oncogenic and tumor suppressive miRNAs. Finally, the clinical prospect of miRNAs as a novel diagnostic and therapeutic intervention will be discussed.
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What is the mechanism of microRNA deregulation in carcinogenesis?
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MicroRNAs are implicated in nearly all major biological and cellular events, and recent findings further link microRNA deregulation to human carcinogenesis.
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HHHFNC and NCPAP produced similar rates of extubation failure.
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Are high-flow nasal cannulae effective for treatment of preterm infants?
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HHHFNC and NCPAP produced similar rates of extubation failure.
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An epigenetic change is defined as an alteration in gene expression that does not involve a change in the DNA sequence. Epigenetic modifications, including DNA methylation, histone modification (acetylation, methylation and phosphorylation) and miRNA, are critical for regulating developmental events. However, aberrant epigenetic mechanisms may lead to pathological consequences such as cardiovascular disease (CAD), neurodegenerative disease, obesity, metabolic disorder, bone and skeletal diseases and various cancers. Given that epigenetic modifications are heritable and reversible, in contrast to genetic changes, they have been identified as promising targets for disease prevention strategies. Over the past few decades, polyphenols, which are widely present in foods such as fruits and vegetables, have been shown to exhibit a broad spectrum of biological activities for human health. Polyphenols reverse adverse epigenetic regulation by altering DNA methylation and histone modification, and they modulate microRNA expression or directly interact with enzymes that result in the reactivation of silenced tumor suppressor genes or the inactivation of oncogenes. Therefore, dietary polyphenol- targeted epigenetics becomes an attractive approach for disease prevention and intervention. In this review, we summarize the current knowledge and underlying mechanisms of the most common dietary polyphenols and their influence on major epigenetic mechanisms associated with disease intervention.
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Are epigenetic modifications implicated in cardiovascular development and disease?
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Epigenetic modifications, including DNA methylation, histone modification (acetylation, methylation and phosphorylation) and miRNA, are critical for regulating developmental events. However, aberrant epigenetic mechanisms may lead to pathological consequences such as cardiovascular disease (CAD), neurodegenerative disease, obesity, metabolic disorder, bone and skeletal diseases and various cancers.
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Transcriptome sequencing allows for analysis of mature RNAs at base pair resolution. Here we show that RNA-seq can also be used for studying nascent RNAs undergoing transcription. We sequenced total RNA from human brain and liver and found a large fraction of reads (up to 40%) within introns. Intronic RNAs were abundant in brain tissue, particularly for genes involved in axonal growth and synaptic transmission. Moreover, we detected significant differences in intronic RNA levels between fetal and adult brains. We show that the pattern of intronic sequence read coverage is explained by nascent transcription in combination with co-transcriptional splicing. Further analysis of co-transcriptional splicing indicates a correlation between slowly removed introns and alternative splicing. Our data show that sequencing of total RNA provides unique insight into the transcriptional processes in the cell, with particular importance for normal brain development.
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Can RNASeq be used for the analysis of nascent transcripts?
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Here we show that RNA-seq can also be used for studying nascent RNAs undergoing transcription
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The Abl tyrosine kinases, Abl and Arg, play a role in the regulation of the actin cytoskeleton by modulating cell-cell adhesion and cell motility. Deregulation of both the actin cytoskeleton and Abl kinases have been implicated in cancers. Abl kinase activity is elevated in a number of metastatic cancers and these kinases are activated downstream of several oncogenic growth factor receptor signaling pathways. However, the role of Abl kinases in regulation of the actin cytoskeleton during tumor progression and invasion remains elusive. Here we identify the Abl kinases as essential regulators of invadopodia assembly and function. We show that Abl kinases are activated downstream of the chemokine receptor, CXCR4, and are required for cancer cell invasion and matrix degradation induced by SDF1α, serum growth factors, and activated Src kinase. Moreover, Abl kinases are readily detected at invadopodia assembly sites and their inhibition prevents the assembly of actin and cortactin into organized invadopodia structures. We show that active Abl kinases form complexes with membrane type-1 matrix metalloproteinase (MT1-MMP), a critical invadopodia component required for matrix degradation. Further, loss of Abl kinase signaling induces internalization of MT1-MMP from the cell surface, promotes its accumulation in the perinuclear compartment and inhibits MT1-MMP tyrosine phosphorylation. Our findings reveal that Abl kinase signaling plays a critical role in invadopodia formation and function, and have far-reaching implications for the treatment of metastatic carcinomas.
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In which process Src, Cortactin and MT1-MMP are playing an essential role?
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We show that active Abl kinases form complexes with membrane type-1 matrix metalloproteinase (MT1-MMP), a critical invadopodia component required for matrix degradation.
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The discovery of proprotein convertase subtilisin-kexin type 9 (PCSK9), a serine protease which binds to the low-density lipoprotein (LDL) receptors and targets the receptors for lysosomal degradation, offered an additional route through which plasma LDL-cholesterol (LDL-C) levels can be controlled. Initially, the therapeutic approaches to reduce circulating levels of PCSK9 were focused on the use of monoclonal antibodies. To that effect, evolocumab and alirocumab, two human monoclonal antibodies directed against PCSK9, given on a background of statin therapy, have been shown to markedly decrease LDL-C levels and significantly reduce cardiovascular risk. The small interfering RNA (siRNA) molecules have been used recently to target the hepatic production of PCSK9. siRNA interferes with the expression of specific genes with complementary nucleotide sequences by affecting the degradation of mRNA post-transcription, thus preventing translation. Inclisiran is a long-acting, synthetic siRNA directed against PCSK9 and it has been shown to significantly decrease hepatic production of PCSK9 and cause a marked reduction in LDL-C levels. This review aims to present and discuss the current clinical and scientific evidence pertaining to inclisiran, which is a new promising agent in the management of hypercholesterolemia.
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What is the mechanism of action of Inclisiran?
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Inclisiran is a long-acting, synthetic siRNA directed against PCSK9 and it has been shown to significantly decrease hepatic production of PCSK9 and cause a marked reduction in LDL-C levels.
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In dividing cells, the RNA-binding protein HuR associates with and stabilizes labile mRNAs encoding proliferative proteins, events that are linked to the increased cytoplasmic presence of HuR. Here, assessment of HuR levels in various vascular pathologies (intimal hyperplasia, atherosclerosis and neointimal proliferation, sclerosis of arterialized saphenous venous graft, and fibromuscular dysplasia) revealed a distinct increase in HuR expression and cytoplasmic abundance within the intima and neointima layers. On the basis of these observations, we postulated a role for HuR in promoting the proliferation of vascular smooth muscle cells. To test this hypothesis directly, we investigated the expression, subcellular localization, and proliferative influence of HuR in human vascular smooth muscle cells (hVSMCs). Treatment of hVSMCs with platelet-derived growth factor increased HuR levels in the cytoplasm, thereby influencing the expression of metabolic, proliferative, and structural genes. Importantly, knockdown of HuR expression by using RNA interference caused a reduction of hVSMC proliferation, both basally and following platelet-derived growth factor treatment. We propose that HuR contributes to regulating hVSMC growth and homeostasis in pathologies associated with vascular smooth muscle proliferation.
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Which are the main functions of the human HuR (ELAVL1) protein in fibroblasts?
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We propose that HuR contributes to regulating hVSMC growth and homeostasis in pathologies associated with vascular smooth muscle proliferation.
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Dinutuximab (ch14.18; Unituxin™) is a chimeric human-mouse monoclonal antibody that binds to the glycolipid antigen disialoganglioside, which is highly expressed on the surface of neuroblastoma cells. This intravenous drug is approved in the EU and USA as combination therapy with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-2 and isotretinoin for the postconsolidation treatment of patients with high-risk neuroblastoma. In a multinational, phase III study in this patient population, event-free survival (EFS) benefits with the dinutuximab-containing regimen versus isotretinoin alone were observed at the time of the primary (p = 0.0115) and confirmatory (p = 0.0330) efficacy analyses, although the observed p-value for the between-group difference in EFS for the primary efficacy analysis did not cross the prespecified boundary for statistical significance (p < 0.0108). Significant and sustained (5 years) overall survival benefits were seen with the dinutuximab-containing regimen versus isotretinoin alone. Despite pretreatment with analgesics, antihistamines and antipyretics, serious adverse reactions have been reported with the dinutuximab-containing regimen, with infusion reactions and neuropathy prompting the US FDA to issue boxed warnings. Dinutuximab administered in combination with GM-CSF, IL-2 and isotretinoin represents an important advance in the postconsolidation treatment of patients with high-risk neuroblastoma, with its benefits outweighing its risks in a patient population with a poor prognosis and limited therapeutic options.
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Dinutuximab is used for treatment of which disease?
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Dinutuximab administered in combination with GM-CSF, IL-2 and isotretinoin represents an important advance in the postconsolidation treatment of patients with high-risk neuroblastoma, with its benefits outweighing its risks in a patient population with a poor prognosis and limited therapeutic options.
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The overall goal of radiogenomics is the identification of genomic markers that are predictive for the development of adverse effects resulting from cancer treatment with radiation. The principal rationale for a focus on toxicity in radiogenomics is that for many patients treated with radiation, especially individuals diagnosed with early-stage cancers, the survival rates are high, and therefore a substantial number of people will live for a significant period of time beyond treatment. However, many of these patients could suffer from debilitating complications resulting from radiotherapy. Work in radiogenomics has greatly benefited from creation of the Radiogenomics Consortium (RGC) that includes investigators at multiple institutions located in a variety of countries. The common goal of the RGC membership is to share biospecimens and data so as to achieve large-scale studies with increased statistical power to enable identification of relevant genomic markers. A major aim of research in radiogenomics is the development of a predictive instrument to enable identification of people who are at greatest risk for adverse effects resulting from cancer treatment using radiation. It is anticipated that creation of a predictive assay characterized by a high level of sensitivity and specificity will improve precision radiotherapy and assist patients and their physicians to select the optimal treatment for each individual.
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What is the aim of the "Radiogenomics Consortium"?
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A major aim of research in radiogenomics is the development of a predictive instrument to enable identification of people who are at greatest risk for adverse effects resulting from cancer treatment using radiation.
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CD38, a type II transmembrane glycoprotein highly expressed in hematological malignancies including multiple myeloma (MM), represents a promising target for mAb-based immunotherapy. In this study, we describe the cytotoxic mechanisms of action of daratumumab, a novel, high-affinity, therapeutic human mAb against a unique CD38 epitope. Daratumumab induced potent Ab-dependent cellular cytotoxicity in CD38-expressing lymphoma- and MM-derived cell lines as well as in patient MM cells, both with autologous and allogeneic effector cells. Daratumumab stood out from other CD38 mAbs in its strong ability to induce complement-dependent cytotoxicity in patient MM cells. Importantly, daratumumab-induced Ab-dependent cellular cytotoxicity and complement-dependent cytotoxicity were not affected by the presence of bone marrow stromal cells, indicating that daratumumab can effectively kill MM tumor cells in a tumor-preserving bone marrow microenvironment. In vivo, daratumumab was highly active and interrupted xenograft tumor growth at low dosing. Collectively, our results show the versatility of daratumumab to effectively kill CD38-expressing tumor cells, including patient MM cells, via diverse cytotoxic mechanisms. These findings support clinical development of daratumumab for the treatment of CD38-positive MM tumors.
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What is the target of daratumumab?
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In this study, we describe the cytotoxic mechanisms of action of daratumumab, a novel, high-affinity, therapeutic human mAb against a unique CD38 epitope. Daratumumab induced potent Ab-dependent cellular cytotoxicity in CD38-expressing lymphoma- and MM-derived cell lines as well as in patient MM cells, both with autologous and allogeneic effector cells.
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A case study of a child with Sotos syndrome, normal intelligence, and autistic disorder is presented. Initial descriptions of Sotos syndrome included severe to mild mental retardation. More recent studies indicate language and learning disabilities with normal intelligence. Our patient met criteria for a diagnosis of autistic disorder. Sotos syndrome is another genetic and neurodevelopmental syndrome that can be associated with autistic as well as communication and language disorders.
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What is Sotos syndrome?
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Sotos syndrome is another genetic and neurodevelopmental syndrome that can be associated with autistic as well as communication and language disorders.
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The classical pathway of complement (CP) can mediate C3 opsonization of Ags responsible for the costimulation and activation of cognate B lymphocytes. In this manner, the complement system acts as a bridge between the innate and adaptive immune systems critical for establishing a humoral response. However, aberrant complement activation is often observed in autoimmune diseases in which C3 deposition on self-antigens may serve to activate self-reactive B cell clones. In this study, we use BIVV009 (Sutimlimab), a clinical stage, humanized mAb that specifically inhibits the CP-specific serine protease C1s to evaluate the impact of upstream CP antagonism on activation and proliferation of normal and autoimmune human B cells. We report that BIVV009 significantly inhibited complement-mediated activation and proliferation of primary human B cells. Strikingly, CP antagonism suppressed human Ig-induced activation of B cells derived from patients with rheumatoid arthritis. These results suggest that clinical use of CP inhibitors in autoimmune patients may not only block complement-mediated tissue damage, but may also prevent the long-term activation of autoimmune B cells and the production of autoantibodies that contribute to the underlying pathologic condition of these diseases.
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What is the target of Sutimlimab?
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s study, we use BIVV009 (Sutimlimab), a clinical stage, humanized mAb that specifically inhibits the CP-specific serine protease C1s to evaluate the impact of upstream CP antagonism on activation and proliferation of normal and autoimmune human B cells. We repor
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Sox9 encodes a HMG-box transcription factor that has been implicated in numerous developmental processes including chondrogenesis, formation of cardiac valves, and neural crest, testis and spinal cord development. Here we show that Sox9 is expressed in the notochord and the sclerotome during mouse development suggesting that the gene may play additional roles in the development of the axial skeleton. We used ubiquitous mosaic inactivation of a conditional Sox9 allele by Cre/loxP-mediated recombination in the mouse to screen for novel functions of Sox9, and revealed that its absence results in severe malformations of the vertebral column. Besides its established role in chondrogenesis, Sox9 is required for maintaining the structural integrity of the notochord. Mutant embryos establish a normal notochord; however, starting from E9.5, the notochord disintegrates in a cranial to caudal manner. The late requirement in notochord development uncovered a function of notochord-derived signals in inducing segmentation of the ventral sclerotome and chondrogenesis. Thus, Sox9 is required for axial skeletogenesis by regulating notochord survival and chondrogenesis.
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Explain the function of SOX9
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Sox9 encodes a HMG-box transcription factor that has been implicated in numerous developmental processes including chondrogenesis, formation of cardiac valves, and neural crest, testis and spinal cord development.
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Resveratrol is a plant-derived polyphenol that extends lifespan and healthspan in model organism. Despite extensive investigation, the biological processes mediating resveratrol's effects have yet to be elucidated. Because repression of translation shares many of resveratrol's beneficial effects, we hypothesized that resveratrol was a modulator of protein synthesis. We studied the effect of the drug on the H4-II-E rat hepatoma cell line. Initial studies showed that resveratrol inhibited global protein synthesis. Given the role of the mammalian Target of Rapamycin (mTOR) in regulating protein synthesis, we examined the effect of resveratrol on mTOR signaling. Resveratrol inhibited mTOR self-phosphorylation and the phosphorylation of mTOR targets S6K1 and eIF4E-BP1. It attenuated the formation of the translation initiation complex eIF4F and increased the phosphorylation of eIF2α. The latter event, also a mechanism for translation inhibition, was not recapitulated by mTOR inhibitors. The effects on mTOR signaling were independent of effects on AMP-activated kinase or AKT. We conclude that resveratrol is an inhibitor of global protein synthesis, and that this effect is mediated through modulation of mTOR-dependent and independent signaling.
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What is the effect of resveratrol on mTOR activity?
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We conclude that resveratrol is an inhibitor of global protein synthesis, and that this effect is mediated through modulation of mTOR-dependent and independent signaling.
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