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Preterm premature rupture of the membranes (PPROM) is responsible for one-third of all preterm births and affects 120,000 pregnancies in the United States each year. Effective treatment relies on accurate diagnosis and is gestational age dependent. The diagnosis of PPROM is made by a combination of clinical suspicion, patient history and some simple tests. PPROM is associated with significant maternal and neonatal morbidity and mortality from infection, umbilical cord compression, placental abruption and preterm birth. Subclinical intrauterine infection has been implicated as a major aetiological factor in the pathogenesis and subsequent maternal and neonatal morbidity associated with PPROM. The frequency of positive cultures obtained by transabdominal amniocentesis at the time of presentation with PPROM in the absence of labour is 25-40%. The majority of amniotic fluid infection in the setting of PPROM does not produce the signs and symptoms traditionally used as diagnostic criteria for clinical chorioamnionitis. Any evidence of infection by amniocentesis should be considered carefully as an indication for delivery. Documentation of amniotic fluid infection in women who present with PPROM enables us to triage our therapeutic decision making rationally. In PPROM, the optimal interval for delivery occurs when the risks of immaturity are outweighed by the risks of pregnancy prolongation (infection, abruption and cord accident). Lung maturity assessment may be a useful guide when planning delivery in the 32- to 34-week interval. A gestational age approach to therapy is important and should be adjusted for each hospital's neonatal intensive care unit. Antenatal antibiotics and corticosteroid therapies have clear benefits and should be offered to all women without contraindications. During conservative management, women should be monitored closely for placental abruption, infection, labour and a non-reassuring fetal status. Women with PPROM after 32 weeks of gestation should be considered for delivery, and after 34 weeks the benefits of delivery clearly outweigh the risks.
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What is PPROM?
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Preterm premature rupture of the membranes (PPROM) is responsible for one-third of all preterm births and affects 120,000 pregnancies in the United States each year.
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The 605 amino acid E1 protein of bovine papillomavirus type 1 (BPV-1) is a multifunctional nuclear protein required for viral DNA replication. A nuclear localization signal (NLS) sequence was previously defined by point mutations in three short adjacent clusters of basic amino acids located in the amino-terminal region of the E1 protein. In this study, we used a fusion protein approach to evaluate the contribution of other regions of the E1 protein to nuclear transport. The nearly full-length E1 gene and six non-overlapping subfragments were each fused in-frame with the lacZ gene in a eukaryotic expression vector. Each clone was electroporated into COS-1 cells, and the intracellular location of the E1-beta-galactosidase fusion proteins was determined by immunofluorescence. Only the constructs containing the full-length E1 or a single subregion (E1-259; amino acids 84 to 166) produced fusion proteins that entered the nucleus. Point mutations in the NLS sequences of the E1-259-lacZ construct prevented nuclear translocation of the corresponding fusion protein. This confirms the previous result that the cluster of basic amino acids is critical for nuclear transport. Furthermore, the data obtained in this investigation indicated that the region of E1 containing the NLS sequence was not only necessary, but was also sufficient for nuclear localization. No other region of E1 contained independent nuclear localization activity.
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Where in a protein can a signal sequence be found?
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A nuclear localization signal (NLS) sequence was previously defined by point mutations in three short adjacent clusters of basic amino acids located in the amino-terminal region of the E1 protein.
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The proteasome inhibitor bortezomib has shown remarkable clinical success in the treatment of multiple myeloma. However, the efficacy and mechanism of action of bortezomib in solid tumor malignancies is less well understood. In addition, the use of this first-in-class proteasome inhibitor is limited by several factors, including off-target effects that lead to adverse toxicities. We recently reported the impact and mechanisms of carfilzomib and oprozomib, second-in-class proteasome inhibitors with higher specificities and reduced toxicities, against head and neck squamous cell carcinoma (HNSCC). Carfilzomib and oprozomib potently inhibit HNSCC cell survival and the growth of HNSCC tumors. Both compounds promote upregulation of proapoptotic BIK and antiapoptotic MCL1, which serves to mediate and attenuate, respectively, the killing activities of these proteasome inhibitors. Both compounds also induce complete autophagic flux that is partially dependent on activation of the unfolded protein response (UPR) and upregulation of ATF4. Carfilzomib- and oprozomib-induced autophagy acts to promote HNSCC cell survival. Our study indicates that the therapeutic benefit of these promising proteasome inhibitors may be improved by inhibiting MCL1 expression or autophagy.
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Are proteasome inhibitors good candidates for treatment of leukemia and solid tumors?
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We recently reported the impact and mechanisms of carfilzomib and oprozomib, second-in-class proteasome inhibitors with higher specificities and reduced toxicities, against head and neck squamous cell carcinoma (HNSCC). Carfilzomib and oprozomib potently inhibit HNSCC cell survival and the growth of HNSCC tumors
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An attenuated Plasmodium falciparum (Pf) sporozoite (SPZ) vaccine, PfSPZ Vaccine, is highly protective against controlled human malaria infection (CHMI) 3 weeks after immunization, but the durability of protection is unknown. We assessed how vaccine dosage, regimen, and route of administration affected durable protection in malaria-naive adults. After four intravenous immunizations with 2.7 × 10(5) PfSPZ, 6/11 (55%) vaccinated subjects remained without parasitemia following CHMI 21 weeks after immunization. Five non-parasitemic subjects from this dosage group underwent repeat CHMI at 59 weeks, and none developed parasitemia. Although Pf-specific serum antibody levels correlated with protection up to 21-25 weeks after immunization, antibody levels waned substantially by 59 weeks. Pf-specific T cell responses also declined in blood by 59 weeks. To determine whether T cell responses in blood reflected responses in liver, we vaccinated nonhuman primates with PfSPZ Vaccine. Pf-specific interferon-γ-producing CD8 T cells were present at ∼100-fold higher frequencies in liver than in blood. Our findings suggest that PfSPZ Vaccine conferred durable protection to malaria through long-lived tissue-resident T cells and that administration of higher doses may further enhance protection.
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Which disease can be prevented with PfSPZ Vaccine?
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An attenuated Plasmodium falciparum (Pf) sporozoite (SPZ) vaccine, PfSPZ Vaccine, is highly protective against controlled human malaria infection (CHMI) 3 weeks after immunization, but the durability of protection is unknown.
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The 15 members of the kallikrein-related serine peptidase (KLK) family have diverse tissue-specific expression profiles and putative proteolytic functions. The kallikrein family is also emerging as a rich source of disease biomarkers with KLK3, commonly known as prostate-specific antigen, being the current serum biomarker for prostate cancer. The kallikrein locus is also notable because it is extraordinarily responsive to steroids and other hormones. Indeed, at least 14 functional hormone response elements have been identified in the kallikrein locus. A more comprehensive understanding of the transcriptional regulation of kallikreins may help the field make more informed hypotheses about the physiological functions of kallikreins and their effectiveness as biomarkers. In this review, we describe the organization of the kallikrein locus and the structure of kallikrein genes and proteins. We also focus on the transcriptional regulation of kallikreins by androgens, progestins, glucocorticoids, mineralocorticoids, estrogens, and other hormones in animal models and human prostate, breast, and reproductive tract tissues. The interaction of the androgen receptor with androgen response elements in the promoter and enhancer of KLK2 and KLK3 is also summarized in detail. There is evidence that all kallikreins are regulated by multiple nuclear receptors. Yet, apart from KLK2 and KLK3, it is not clear whether all kallikreins are direct transcriptional targets. Therefore, we argue that gaining more detailed information about the mechanisms that regulate kallikrein expression should be a priority of future studies and that the kallikrein locus will continue to be an important model in the era of genome-wide analyses.
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How many tissue kallikrein genes are present in the human genome?
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In this review, we describe the organization of the kallikrein locus and the structure of kallikrein genes and proteins.
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Between 1989 and 2004, the prevalence of gestational diabetes mellitus (GDM) in the United States increased by 122%. Glycated haemoglobin, as measured by haemoglobin A1C (A1C), can potentially identify pregnant women at high risk for adverse outcomes associated with GDM including macrosomia and post-partum glucose intolerance. Our objective was to systematically review the literature with respect to A1C levels during pregnancy and associated maternal and offspring outcomes. We used MEDLINE to identify relevant publications from 1975 to 2009. We included articles if they met the following criteria: original full text articles in English; primary exposure of antepartum A1C; women with GDM at baseline or who developed GDM during the study; primary outcome of GDM, insulin use, post-partum abnormal glucose or type 2 diabetes (T2DM), birthweight, macrosomia or large for gestational age. Case series and case reports were excluded. Twenty studies met our criteria. A1C at GDM diagnosis was positively associated with post-partum abnormal glucose. Women with post-partum T2DM or impaired glucose tolerance had mean A1C at GDM diagnosis higher than those with normal post-partum glucose (P ≤ 0.002) and a 1% increase in A1C at GDM diagnosis was associated with 2.36 times higher odds of post-partum abnormal glucose 6 weeks after delivery [95% confidence interval 1.19, 4.68]. The association of A1C and birthweight varied substantially between studies, with correlation coefficients ranging from 0.11 to 0.51. A1C, a less burdensome and costly measure than an oral glucose tolerance test, appears to be an attractive measure for identifying women at high risk of adverse outcomes associated with GDM.
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What does A1C measure?
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Glycated haemoglobin, as measured by haemoglobin A1C (A1C), c
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National guidance (executive letter) EL(97)12 stated that population screening should not be provided by the NHS, or be offered to the public until there is effective screening technology for prostate cancer. The study set out to determine the views of general practitioners and, indirectly, their practice staff on prostate cancer screening in primary care upon receiving EL(97)12. This postal questionnaire survey reveals that 81% (95% CI 75% to 87%) of responding general practitioners in North Staffordshire agreed with EL(97)12 and one in ten said that the executive letter changed their views, suggesting that such national guidance has an effect.
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What is known about prostate cancer screening in the UK ?
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National guidance (executive letter) EL(97)12 stated that population screening should not be provided by the NHS, or be offered to the public until there is effective screening technology for prostate cancer.
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Unlike normal mammalian cells, which use oxygen to generate energy, cancer cells rely on glycolysis for energy and are therefore less dependent on oxygen. We previously observed that the c-Myc oncogenic transcription factor regulates lactate dehydrogenase A and induces lactate overproduction. We, therefore, sought to determine whether c-Myc controls other genes regulating glucose metabolism. In Rat1a fibroblasts and murine livers overexpressing c-Myc, the mRNA levels of the glucose transporter GLUT1, phosphoglucose isomerase, phosphofructokinase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and enolase were elevated. c-Myc directly transactivates genes encoding GLUT1, phosphofructokinase, and enolase and increases glucose uptake in Rat1 fibroblasts. Nuclear run-on studies confirmed that the GLUT1 transcriptional rate is elevated by c-Myc. Our findings suggest that overexpression of the c-Myc oncoprotein deregulates glycolysis through the activation of several components of the glucose metabolic pathway.
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Which are the major transcription factors regulating glycolysis in mammals?
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overexpression of the c-Myc oncoprotein deregulates glycolysis through the activation of several components of the glucose metabolic pathway
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Silencing of the paternal allele of three imprinted genes (Igf2r, Slc22a2 and Slc22a3) requires cis expression of the Air RNA that overlaps the promoter of one of them (Igf2r). Air is a non-coding RNA whose mode of action is unknown. We tested the role of the Igf2r promoter and the role of transcriptional overlap between Igf2r and Air in silencing in this cluster. We analyzed imprinted expression in mice in which the Igf2r promoter is replaced by a thymidine kinase promoter that preserves a transcription overlap with Air, and in mice with a deleted Igf2r promoter that lack any transcriptional overlap with Air. Imprinted silencing of Air, Slc22a2 and Slc22a3 is maintained by the replacement promoter and also in the absence of transcriptional overlap with Air. These results exclude a role for the Igf2r promoter and for transcriptional overlap between Igf2r and Air in silencing Air, Slc22a2 and Slc22a3. Although these results do not completely exclude a role for a double-stranded RNA silencing mechanism, they do allow the possibility that the Air RNA has intrinsic cis silencing properties.
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How is Slc22a3 imprinted?
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These results exclude a role for the Igf2r promoter and for transcriptional overlap between Igf2r and Air in silencing Air, Slc22a2 and Slc22a3
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Lysyl oxidase like-2 (LOXL2) belongs to the lysyl oxidase (LOX) family, which comprises Cu(2+)- and lysine tyrosylquinone (LTQ)-dependent amine oxidases. LOXL2 is proposed to function similarly to LOX in the extracellular matrix (ECM) by promoting crosslinking of collagen and elastin. LOXL2 has also been proposed to regulate extracellular and intracellular cell signaling pathways. Dysregulation of LOXL2 has been linked to many diseases, including cancer, pro-oncogenic angiogenesis, fibrosis and heart diseases. In this review, we will give an overview of the current understandings and hypotheses regarding the molecular functions of LOXL2.
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What is the function of LOX proteins in the ECM?
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LOXL2 is proposed to function similarly to LOX in the extracellular matrix (ECM) by promoting crosslinking of collagen and elastin.
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The Melkersson-Rosenthal syndrome is a rare disorder of unknown etiology characterized by a triad of recurrent orofacial swelling, relapsing facial paralysis, and fissured tongue. Exacerbations and recurrences are common. The orofacial swelling is characterized by fissured, reddish-brown, swollen, nonpruritic lips or firm edema of the face. The facial palsy is indistinguishable from Bell's palsy. The fissured tongue is seen in one third to one half of patients and, although the least common manifestation, its presence assists in diagnosis. The classic triad is not seen frequently in its complete form; therefore, diagnosis is difficult. This is particularly true because monosymptomatic and oligosymptomatic variants are seen more commonly. Cheilitis granulomatosa of Miescher is an example of a monosymptomatic variant of the Melkersson-Rosenthal syndrome. The histologic findings of noncaseating, sarcoidal granulomas support the diagnosis. These granulomas are not invariably present, and their absence does not exclude the diagnosis of the Melkersson-Rosenthal syndrome. Thus, the Melkersson-Rosenthal syndrome is a disease with elements of orofacial granulomatosis. Orofacial granulomatosis is a clinicopathologic entity describing oral lesions with noncaseating granulomas. The spectrum of this entity includes patients with oral Crohn's disease, patients with oral lesions who will develop typical bowel symptoms of Crohn's disease in the ensuing months to years, patients with tooth-associated infections, patients with sarcoidosis, and patients with food or contact allergies. The value of the clinicopathologic construct of orofacial granulomatosis is to provoke the careful search for provocative causes for the reactive symptom complex of the Melkersson-Rosenthal syndrome.
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What is the triad of Melkersson-Rosenthal syndrome?
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The Melkersson-Rosenthal syndrome is a rare disorder of unknown etiology characterized by a triad of recurrent orofacial swelling, relapsing facial paralysis, and fissured tongue.
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Individuals with cancer are disproportionately affected by sleep disturbance and insomnia relative to the general population. These problems can be a consequence of the psychological, behavioral, and physical effects of a cancer diagnosis and treatment. Insomnia often persists for years and, when combined with already high levels of cancer-related distress, may place cancer survivors at a higher risk of future physical and mental health problems and poorer quality of life. The recommended first-line treatment for insomnia is cognitive behavioral therapy for insomnia (CBT-I), a non-pharmacological treatment that incorporates cognitive and behavior-change techniques and targets dysfunctional attitudes, beliefs, and habits involving sleep. This article presents a comprehensive review of the literature examining the efficacy of CBT-I on sleep and psychological outcomes in cancer patients and survivors. The search revealed 12 studies (four uncontrolled, eight controlled) that evaluated the effects of CBT-I in cancer patients or survivors. Results suggest that CBT-I is associated with statistically and clinically significant improvements in subjective sleep outcomes in patients with cancer. CBT-I may also improve mood, fatigue, and overall quality of life, and can be successfully delivered through a variety of treatment modalities, making it possible to reach a broader range of patients who may not have access to more traditional programs. Future research in this area should focus on the translation of evidence into clinical practice in order to increase awareness and access to effective insomnia treatment in cancer care.
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Can cognitive behavioral therapy improve fatigue in cancer patients?
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CBT-I may also improve mood, fatigue, and overall quality of life, and can be successfully delivered through a variety of treatment modalities, making it possible to reach a broader range of patients who may not have access to more traditional programs.
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The larval nervous system of the ascidian Ciona intestinalis exhibits an abstract form of the vertebrate nervous system. The Ci-Galphai1 gene, which encodes a G-protein alpha subunit, is specifically expressed in distinct sets of neurons in C. intestinalis larvae, including papillar neurons of the adhesive organ, ocellus photoreceptor cells, and cholinergic and GABAergic neurons in the central nervous system (CNS). A GFP reporter gene driven by the 4.2-kb 5' flanking region of Ci-Galphai1 recapitulated the endogenous gene expression patterns. Comparative genomic analysis of the Galphai1 gene between C. intestinalis and Ciona savignyi identified an 87-bp highly conserved non-coding sequence located between -3176 and -3090 bp upstream of the gene. Deletion of this conserved upstream sequence resulted in the complete loss of reporter expression in the central nervous system, while reporter expression in the adhesive organ and mesenchyme cells remained unaffected. The conserved upstream sequence can activate gene expression from basal promoters in the brain vesicle, although it requires additional cis-regulatory sequences to fully activate the CNS-specific gene expression. These results suggest that different types of central neurons share a common transcriptional activation mechanism that is different from that of papillar neurons.
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How are CRM (cis-regulatory modules) defined?
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The conserved upstream sequence can activate gene expression from basal promoters in the brain vesicle, although it requires additional cis-regulatory sequences to fully activate the CNS-specific gene expression.
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The mammalian nonapeptide hormones, vasopressin and oxytocin, are known to be potent regulators of social behaviour. Teleost fishes possess vasopressin and oxytocin homologues known as arginine vasotocin (AVT) and isotocin (IT), respectively. The role of these homologous nonapeptides in mediating social behaviour in fishes has received far less attention. The extraordinarily large number of teleost fish species and the impressive diversity of their social systems provide us with a rich test bed for investigating the role of nonapeptides in regulating social behaviour. Existing studies, mostly focused on AVT, have revealed relationships between the nonapeptides, and both social behaviour and dominance status in fishes. To date, much of the work on endogenous nonapeptides in fish brains has measured genomic or neuroanatomical proxies of nonapeptide production rather than the levels of these molecules in the brain. In this study, we measure biologically available AVT and IT levels in the brains of Neolamprologus pulcher, a cooperatively breeding cichlid fish, using high performance liquid chromatography with fluorescence detection. We found that brain AVT levels were higher in the subordinate than in dominant animals, and levels of IT correlated negatively with the expression of affiliative behaviour. We contrast these results with previous studies, and we discuss the role the nonapeptide hormones may play in the regulation of social behaviour in this highly social animal.
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Isotocin is an homolog of what hormone?
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eost fishes possess vasopressin and oxytocin homologues known as arginine vasotocin (AVT) and isotocin (IT), respectively. The r
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Intestinal microvillous disorders are an uncommon cause of severe diarrhea, with very poor prognosis. The authors report the case of a female infant with Down syndrome, aganglionic megacolon, severe diarrhea, and jejunal biopsy with ultrastructural changes consistent with microvillous atrophy. The patient condition improved after a colostomy performed in the setting of the treatment of Hirschprung disease.
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Is aganglionic megacolon a feature of Down syndrome?
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The authors report the case of a female infant with Down syndrome, aganglionic megacolon, severe diarrhea, and jejunal biopsy with ultrastructural changes consistent with microvillous atrophy
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Interactive data visualization is imperative in the biological sciences. The development of independent layers of interactivity has been in pursuit in the visualization community. We developed bigPint, a data visualization package available on Bioconductor under the GPL-3 license (https://bioconductor.org/packages/release/bioc/html/bigPint.html). Our software introduces new visualization technology that enables independent layers of interactivity using Plotly in R, which aids in the exploration of large biological datasets. The bigPint package presents modernized versions of scatterplot matrices, volcano plots, and litre plots through the implementation of layered interactivity. These graphics have detected normalization issues, differential expression designation problems, and common analysis errors in public RNA-sequencing datasets. Researchers can apply bigPint graphics to their data by following recommended pipelines written in reproducible code in the user manual. In this paper, we explain how we achieved the independent layers of interactivity that are behind bigPint graphics. Pseudocode and source code are provided. Computational scientists can leverage our open-source code to expand upon our layered interactive technology and/or apply it in new ways toward other computational biology tasks.
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Describe bigPint
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Interactive data visualization is imperative in the biological sciences. The development of independent layers of interactivity has been in pursuit in the visualization community. We developed bigPint, a data visualization package available on Bioconductor under the GPL-3 license (https://bioconductor.org/packages/release/bioc/html/bigPint.html). Our software introduces new visualization technology that enables independent layers of interactivity using Plotly in R, which aids in the exploration of large biological datasets. The bigPint package presents modernized versions of scatterplot matrices, volcano plots, and litre plots through the implementation of layered interactivity. These graphics have detected normalization issues, differential expression designation problems, and common analysis errors in public RNA-sequencing datasets. Researchers can apply bigPint graphics to their data by following recommended pipelines written in reproducible code in the user manual. In this paper, we explain how we achieved the independent layers of interactivity that are behind bigPint graphics. Pseudocode and source code are provided. Computational scientists can leverage our open-source code to expand upon our layered interactive technology and/or apply it in new ways toward other computational biology tasks.
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Engineered T cell therapies targeting cancer antigens have demonstrated significant efficacy in specific patient populations. Most impressively, CD19-directed chimeric antigen receptor T cells (CART19) have led to impressive responses in patients with B-cell leukemia and lymphoma. CTL019, or KYMRIAH™ (tisagenlecleucel), a CD19 CAR T cell product developed by Novartis and the University of Pennsylvania, was recently approved for clinical use by the Food and Drug Administration, representing a landmark in the application of adoptive T cell therapies. As CART19 enters routine clinical use, improving the efficacy of this exciting platform is the next step in broader application. Novel gene-editing technologies like CRISPR-Cas9 allow facile editing of specific genes within the genome, generating a powerful platform to further optimize the activity of engineered T cells.
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What is the mechanism of action of Tisagenlecleucel?
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Most impressively, CD19-directed chimeric antigen receptor T cells (CART19) have led to impressive responses in patients with B-cell leukemia and lymphoma. CTL019, or KYMRIAH™ (tisagenlecleucel), a CD19 CAR T cell product developed by Novartis and the University of Pennsylvania, was recently approved for clinical use by the Food and Drug Administration, representing a landmark in the application of adoptive T cell therapies.
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Circular RNAs (circRNAs) are a large class of transcripts in the mammalian genome. Although the translation of circRNAs was reported, additional coding circRNAs and the functions of their translated products remain elusive. Here, we demonstrate that an endogenous circRNA generated from a long noncoding RNA encodes regulatory peptides. Through ribosome nascent-chain complex-bound RNA sequencing (RNC-seq), we discover several peptides potentially encoded by circRNAs. We identify an 87-amino-acid peptide encoded by the circular form of the long intergenic non-protein-coding RNA p53-induced transcript (LINC-PINT) that suppresses glioblastoma cell proliferation in vitro and in vivo. This peptide directly interacts with polymerase associated factor complex (PAF1c) and inhibits the transcriptional elongation of multiple oncogenes. The expression of this peptide and its corresponding circRNA are decreased in glioblastoma compared with the levels in normal tissues. Our results establish the existence of peptides encoded by circRNAs and demonstrate their potential functions in glioblastoma tumorigenesis.
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List types of cancer where Long intergenic nonprotein coding RNA p53-induced transcript (LINC-PINT) is involved
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We identify an 87-amino-acid peptide encoded by the circular form of the long intergenic non-protein-coding RNA p53-induced transcript (LINC-PINT) that suppresses glioblastoma cell proliferation in vitro and in vivo. This peptide directly interacts with polymerase associated factor complex (PAF1c) and inhibits the transcriptional elongation of multiple oncogenes. The expression of this peptide and its corresponding circRNA are decreased in glioblastoma compared with the levels in normal tissues. Our results establish the existence of peptides encoded by circRNAs and demonstrate their potential functions in glioblastoma tumorigenesis.
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Members of the apolipoprotein B mRNA editing complex polypeptide 1-like (APOBEC) family of enzymes exhibit inhibitory activity against a variety of exogenous and endogenous retroviruses including retrotransposons, such as long interspersed element 1 (LINE-1). Indeed, human APOBEC3A, APOBEC3B, and APOBEC3F inhibit retrotransposition of human LINE-1, mouse IAP and MusD retrotransposons. In our study, we examined whether the inhibitory effect of APOBEC3 proteins correlates with APOBEC3 ability to bind the LINE-1 ORF1 protein. We examined the interactions between the LINE-1 ORF1 protein and the most potent LINE-1 retrotransposon inhibitors, human APOBEC3A and APOBEC3B, by immunofluorescence and immunoprecipitation. Although human APOBEC3A shows the highest inhibitory potency against LINE-1 retrotransposon, no direct interactions were identified either by immunofluorescence or by co-immunoprecipitation. APOBEC3B binds to LINE-1 ORF1 protein, yet no co-localization was detected. We concluded that APOBEC3 proteins interfere indirectly with the LINE-1 retrotransposition pathway, probably through interference with RNA targeting.
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Which proteins induce inhibition of LINE-1 and Alu retrotransposition?
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We concluded that APOBEC3 proteins interfere indirectly with the LINE-1 retrotransposition pathway, probably through interference with RNA targeting.
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Mannose 6-phosphate receptors carry newly synthesized lysosomal hydrolases from the trans-Golgi network to endosomes, then return to the trans-Golgi network for another round of enzyme delivery. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, interferes with the delivery of newly synthesized lysosomal enzymes to lysosomes. We used two independent assays of mannose 6-phosphate receptor trafficking to determine the precise step that is blocked by wortmannin. Using an assay that monitors resialylation of desialylated cell surface 300-kDa mannose 6-phosphate receptors, we found that receptor endocytosis and transport to the trans-Golgi network were not inhibited by 2 microM wortmannin. In addition, this concentration of drug had no effect on the transport of the mannose 6-phosphate receptor from late endosomes to the trans-Golgi network using a system that reconstitutes this transport process in cell extracts. Under the same conditions, wortmannin significantly inhibited the generation of mature cathepsin D. In addition, the structurally unrelated phosphatidylinositol 3-kinase inhibitor, LY294002, was also without effect when added to in vitro endosome-trans-Golgi network transport reactions. These experiments demonstrate that the interruption in lysosomal enzyme targeting is most likely due to a wortmannin-sensitive process required for the export of these receptors from the trans-Golgi network, consistent with the established role of phosphatidylinositol 3-kinase in the equivalent transport process in Saccharomyces cerevisiae.
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Which receptor(s) recognize lysosomal hydrolases in trans-Golgi network (TGN)?
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Mannose 6-phosphate receptors carry newly synthesized lysosomal hydrolases from the trans-Golgi network to endosomes, then return to the trans-Golgi network for another round of enzyme delivery.
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Previous studies have shown that acquired prosopagnosia is characterized by impairment at holistic/configural processing. However, this view is essentially supported by studies performed with patients whose face recognition difficulties are part of a more general visual (integrative) agnosia. Here, we tested the patient PS, a case of acquired prosopagnosia whose face-specific recognition difficulties have been related to the inability to process individual faces holistically (absence of inversion, composite, and whole-part effects with faces). Here, we show that in contrast to this impairment, the patient presents with an entirely normal response profile in a Navon hierarchical letter task: she was as fast as normal controls, faster to identify global than local letters, and her sensitivity to global interference during identification of local letters was at least as large as normal observers. These observations indicate that holistic processing as measured with global/local interference in the Navon paradigm is functionally distinct from the ability to perceive an individual face holistically.
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is prosopagnosia inherited or acquired?
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Previous studies have shown that acquired prosopagnosia is characterized by impairment at holistic/configural processing.
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Alterations in fibroblast growth factor receptor (FGFR) genes have been identified as potential driver oncogenes. Pharmacological targeting of FGFRs may therefore provide therapeutic benefit to selected cancer patients, and proof-of-concept has been established in early clinical trials of FGFR inhibitors. Here, we present the molecular structure and preclinical characterization of INCB054828 (pemigatinib), a novel, selective inhibitor of FGFR 1, 2, and 3, currently in phase 2 clinical trials. INCB054828 pharmacokinetics and pharmacodynamics were investigated using cell lines and tumor models, and the antitumor effect of oral INCB054828 was investigated using xenograft tumor models with genetic alterations in FGFR1, 2, or 3. Enzymatic assays with recombinant human FGFR kinases showed potent inhibition of FGFR1, 2, and 3 by INCB054828 (half maximal inhibitory concentration [IC50] 0.4, 0.5, and 1.0 nM, respectively) with weaker activity against FGFR4 (IC50 30 nM). INCB054828 selectively inhibited growth of tumor cell lines with activation of FGFR signaling compared with cell lines lacking FGFR aberrations. The preclinical pharmacokinetic profile suggests target inhibition is achievable by INCB054828 in vivo with low oral doses. INCB054828 suppressed the growth of xenografted tumor models with FGFR1, 2, or 3 alterations as monotherapy, and the combination of INCB054828 with cisplatin provided significant benefit over either single agent, with an acceptable tolerability. The preclinical data presented for INCB054828, together with preliminary clinical observations, support continued investigation in patients with FGFR alterations, such as fusions and activating mutations.
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What are the targets of pemigatinib?
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we present the molecular structure and preclinical characterization of INCB054828 (pemigatinib), a novel, selective inhibitor of FGFR 1, 2, and 3, currently in phase 2 clinical trials. INCB054828
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Type 1 diabetes is an organ-specific autoimmune disease characterized by T cell-mediated destruction of pancreatic beta cells. In Japanese population, the incidence of type 1 diabetes in children is very low compared to European countries. However, there are more patients with type 1 diabetes in adults, including latent autoimmune diabetes in adults (LADA). The circulating autoantibodies to multiple islet autoantigens including GAD, insulin, and IA-2 are the important immunological features of type 1 diabetes. The prevalences of anti-islet autoantibodies in patients with Japanese type 1 diabetes are 60-70% for GAD autoantibodies, 45-50% for insulin autoantibodies (IAA), and 60-65% for IA-2 autoantibodies at disease onset, which are similar to those reported in Caucasian patients. With combinatorial analysis of these autoantibodies, 90% of patients express at least one of these autoantibodies and are classified as type 1A diabetes. Although the majority of patients with type 1 diabetes are young, lean, and ketosis-prone, there are a number of patients with type 1 diabetes initially diagnosed as having type 2 diabetes at disease onset called LADA. These patients with LADA often progress toward an insulin-deficient state within several years after diagnosis. High levels of GAD autoantibodies have a high predictive value for future insulin deficiency in LADA. Further, epitope analysis of GAD65 autoantibodies may be helpful to predict future insulin dependency in LADA patients. In conclusion, Japanese patients with type 1 diabetes are clinically heterogeneous and the determination of immunological features are helpful to clarify the characteristics of the Japanese type 1 diabetic syndrome.
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List autoimmune disorders associated with GAD65 autoantibodies.
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The circulating autoantibodies to multiple islet autoantigens including GAD, insulin, and IA-2 are the important immunological features of type 1 diabetes.
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Viltolarsen is a phosphorodiamidate morpholino antisense oligonucleotide (PMO) designed to skip exon 53 of the DMD gene for the treatment of Duchenne muscular dystrophy (DMD), one of the most common lethal genetic disorders characterized by progressive degeneration of skeletal muscles and cardiomyopathy. It was developed by Nippon Shinyaku in collaboration with the National Center of Neurology and Psychiatry (NCNP) in Japan based on the preclinical studies conducted in the DMD dog model at the NCNP. After showing hopeful results in pre-clinical trials and several clinical trials across North America and Japan, it received US Food and Drug Administration (FDA) approval for DMD in 2020. Viltolarsen restores the reading frame of the DMD gene by skipping exon 53 and produces a truncated but functional form of dystrophin. It can treat approximately 8-10% of the DMD patient population. This paper aims to summarize the development of viltolarsen from preclinical trials to clinical trials to, finally, FDA approval, and discusses the challenges that come with fighting DMD using antisense therapy.
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Is viltolarsen effective for the treatment of Duchenne muscular dystrophy?
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Viltolarsen is a phosphorodiamidate morpholino antisense oligonucleotide (PMO) designed to skip exon 53 of the DMD gene for the treatment of Duchenne muscular dystrophy (DMD)
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The SET domain, first identified within and named after proteins encoded by three Drosophila genes [Su(var)3-9, E(z), and Trithorax], is recognized as a signature motif for histone methyltransferases that are involved in epigenetic processes. The SUV39H family of SET domain proteins methylate specifically the residue lysine 9 of histone H3, creating a code for gene silencing. This family of proteins contain at their C termini a unique catalytic domain consisting of pre-SET, SET, and post-SET domains. Sequence homology-based searches identified 15 Arabidopsis, 14 maize, and 12 rice proteins that can be assigned to the SUV39H family. These high numbers in plants are in marked contrast to the situation in animals, in which each species appears to contain only two to three proteins of this family. Our phylogenetic analyses revealed that plant proteins can be classified into seven orthology groups. Representative members of each group can be found in single plant species, suggesting that different group members are evolutionarily conserved to perform specific functions.
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What is the characteristic domain of histone methyltransferases?
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SET domain, first identified within and named after proteins encoded by three Drosophila genes [Su(var)3-9, E(z), and Trithorax], is recognized as a signature motif for histone methyltransferases
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We have performed an entire-population-based survey of the epidemiology and penetrance of Leber hereditary optic neuropathy (LHON) in Finland - a country that is among the best-studied genetic isolates in the world. During our long-term clinical follow-up period since 1970, we have so far identified 36 LHON families in Finland, comprised of almost 1000 family members. Counting the unaffected family members has been possible thanks to accessible genealogical records, and this has improved the accuracy of our penetrance figures by minimizing the sample bias. Our results, although confirming some well-known features of LHON, indicate that the overall penetrance of LHON is lower than previously estimated, and that affected females have a higher incidence of affected offspring compared to the unaffected females. The prevalence of LHON in Finland is 1:50 000, and one in 9000 Finns is a carrier of one of the three LHON primary mutations.
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What is LHON, also known as Lebers syndrome?
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Leber hereditary optic neuropathy (LHON)
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With an ageing population and improving cancer therapies, the two most common benign and malignant bone diseases, osteoporosis and bone metastases, will continue to affect an increasing number of patients. Our expanding knowledge of the molecular processes underlying these conditions has resulted in novel bone targets that are currently being explored in clinical trials. Clearly, the approval of denosumab, a monoclonal antibody directed against RANKL, has just marked the beginning of a new era for bone therapy with several additional new therapies lining up for clinical approval in the coming years. Potential agents targeting the osteoclast include cathepsin K, currently in phase 3 trials, and src inhibitors. Amongst anabolic agents, inhibitors of the Wnt-inhibitor sclerostin and dickkopf-1 are promising in clinical trials. Here, we will provide a comprehensive overview of the most promising agents currently explored for the treatment of bone diseases.
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To the ligand of which receptors does Denosumab (Prolia) bind?
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Clearly, the approval of denosumab, a monoclonal antibody directed against RANKL, has just marked the beginning of a new era for bone therapy with several additional new therapies lining up for clinical approval in the coming years.
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Hot water epilepsy is a reflex or sensory epilepsy in which seizures are triggered by the stimulus of bathing in hot water. Although there is evidence of a genetic basis to its etiology, no gene associated with this disorder has so far been found. In order to identify the genetic locus involved in the pathophysiology of hot water epilepsy, we performed a genome-wide linkage analysis in a four-generation family manifesting the disorder in an autosomal dominant manner. Significant linkage was detected on chromosome 4q24-q28, with the highest two-point LOD score of 3.50 at recombination value (theta) of 0 for the marker D4S402. Centromere-proximal and centromere-distal boundaries of this locus were defined by the markers D4S1572 and D4S2277, respectively. The critical genetic interval spans 22.5 cM and corresponds to about 24 megabases of DNA. The genes NEUROG2, ANK2, UGT8 and CAMK2D, which are known to be expressed in human brain, are strong positional candidates and we propose to examine these and other genes in the locus to identify the causative gene for this intriguing form of epilepsy.
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Describe Hot water reflex epilepsy.
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Hot water epilepsy is a reflex or sensory epilepsy in which seizures are triggered by the stimulus of bathing in hot water
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The results indicate that a daily intake of atemoya would not change the pharmacokinetics of CYP1A2 substrates such as phenacetin as well as CYP2C9- and CYP3A-substrate drugs.
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Does daily atemoya juice intake change the pharmacokinetics of CYP1A2 substrates?
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The results indicate that a daily intake of atemoya would not change the pharmacokinetics of CYP1A2 substrates such as phenacetin as well as CYP2C9- and CYP3A-substrate drugs.
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The proper expression and function of several unconventional myosins are necessary for inner-ear function. Mutations in MYO7A and MYO15 cause deafness in humans, and mice. Whereas mutations in Myo6 cause inner-ear abnormalities in mice, as yet no human deafness has been found to the result of mutations in MYO6. In the mammalian inner ear there are at least nine different unconventional myosin isozymes expressed. Myosin 1 beta, VI, VIIa and probably XV are all expressed within a single cell in the inner ear, the hair cell. The myosin isozymes expressed in the hair cell all have unique domains of expression and in some areas, such as the pericuticular necklace, several domains overlap. This suggests that these myosins all have unique functions and that all are individually targeted within the hair cell. The mouse is proving to be a useful model organism for studying both human deafness and elucidating the normal functions of unconventional myosins in vivo.
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Which myosin isozymes are located within the pericuticular necklace of the hair cell?
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Myosin 1 beta, VI, VIIa and probably XV are all expressed within a single cell in the inner ear, the hair cell.
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Nucleosome dynamics facilitated by histone turnover is required for transcription as well as DNA replication and repair. Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me). In order to correlate histone modifications and transcription-dependent histone turnover, we performed genome wide analyses for euchromatic regions in G2/M-arrested fission yeast. The results show that transcription-dependent histone turnover at 5' promoter and 3' termination regions is directly correlated with the occurrence of H3K56Ac and H4K20 mono-methylation (H4K20me1) in actively transcribed genes. Furthermore, the increase of H3K56Ac and H4K20me1 and antisense RNA production was observed in the absence of the histone H3K36 methyltransferase Set2 and histone deacetylase complex (HDAC) that are involved in the suppression of histone turnover within the coding regions. These results together indicate that H4K20me1 as well as H3K56Ac are bona fide marks for transcription-dependent histone turnover in fission yeast.
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Is H4K20 methylation associated with DNA replication?
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These results together indicate that H4K20me1 as well as H3K56Ac are bona fide marks for transcription-dependent histone turnover in fission yeast.
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The Apert syndrome hand demonstrates many typical clinical features including syndactyly, symbrachyphalangism, and growth disturbances. This is due to the grossly abnormal anatomy of both the skeletal and soft-tissue structures associated with a progressive disease process. This paper presents a clinical, radiologic, and histologic analysis of the Apert syndrome hand anatomy and correlates it with the clinical manifestations. It also links hand and craniofacial dysplasia to other regions of the skeleton as well as the overall disease process. From our analysis, we conclude that there is a genetic anomaly causing variable and uncoordinated differentiation of the mesenchyme at the time of embryologic separation into its various skeletal components, particularly in the distal limb bud and craniofacial skeleton. This disease process continues postnatally in endochondral bone growth center malformation and malfunction as well as ectopic cartilage ossification in soft tissues. We discuss the role of abnormal musculotendinous anatomy and altered biomechanical forces in relation to these processes.
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What hand deformities do patients with Apert syndrome present with?
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The Apert syndrome hand demonstrates many typical clinical features including syndactyly, symbrachyphalangism, and growth disturbances.
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Hyperthermic intraperitoneal chemotherapy (HIPEC) represents a new treatment strategy aimed to improve outcome of patients with advanced ovarian cancer. Based on theoretical and experimental basis, HIPEC should stand as an effective treatment for ovarian cancer. Literature review reveals a number of different experiences on feasibility of this technique, but scientific evidence of current studies remains poor. Much more research is still required to elucidate unanswered questions. Before this technique can be routinely used, some controversial aspects have to be defined: which drug is the best to deliver and at what temperature, is it necessary to use mono- or poly-chemotherapy regimens, which is the time-point for HIPEC in the natural history of ovarian cancer: at front-line therapy, at interval debulking following initial neo-adjuvant chemotherapy, at consolidation following front-line therapy, or at the time of recurrence. Nevertheless, we must not forget that the most important issue in ovarian cancer prognosis is maximal cytoreductive surgery, with no residual disease at completion of initial surgery.
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Could Hyperthermic intraperitoneal chemotherapy (HIPEC) be effective for the treatment of recurrent ovarian cancer?
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Hyperthermic intraperitoneal chemotherapy (HIPEC) represents a new treatment strategy aimed to improve outcome of patients with advanced ovarian cancer.
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Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohn's disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE. Because these reports on association were not always evaluated in multiple ethnic groups and because ethnic difference in allele frequency of the variants has been also reported, we investigated allele frequencies of nine SNPs in four autoimmune-disease-associated loci in Caucasian, African-descent, and Japanese populations. Although SNPs in PADI4 had similar allele frequency among three groups [maximal difference 11%; (P >0.05)], the other three loci revealed statistically significant allele frequency differences (maximal difference 39% (P <0.00001), 13% (P <0.00001), and 8% (P <0.00001) in SLC22A4, PDCD1, and PTPN22, respectively). Of note, three SNPs in the three loci that had allele frequency more than 8% in the Caucasian population were either not polymorphic at all or extremely rare in the Japanese population. Our data suggest that ethnic variations of polymorphisms should be evaluated in detail, and differences should be incorporated into investigations of susceptibility variants for common diseases.
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Is the PTPN22 gene a biomarker for Rheumatoid Arthritis?
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Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohn's disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE
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Hox genes are essential regulators of embryonic development. Their step-wise transcriptional activation follows their genomic topology and the various states of activation are subsequently memorized into domains of progressively overlapping gene products. We have analyzed the 3D chromatin organization of Hox clusters during their early activation in vivo, using high-resolution circular chromosome conformation capture. Initially, Hox clusters are organized as single chromatin compartments containing all genes and bivalent chromatin marks. Transcriptional activation is associated with a dynamic bi-modal 3D organization, whereby the genes switch autonomously from an inactive to an active compartment. These local 3D dynamics occur within a framework of constitutive interactions within the surrounding Topological Associated Domains, indicating that this regulation process is mostly cluster intrinsic. The step-wise progression in time is fixed at various body levels and thus can account for the chromatin architectures previously described at a later stage for different anterior to posterior levels.DOI: http://dx.doi.org/10.7554/eLife.02557.001.
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How many topological associated domains are contained in the human Hox cluster?
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Initially, Hox clusters are organized as single chromatin compartments containing all genes and bivalent chromatin marks.
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The detailed characterization at the molecular biology level of this novel XK splice site mutation associated with the clinical description of the patient contributes to a better understanding of the phenotype-genotype correlation in the McLeod syndrome.
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Mutation of which gene is associated with McLeod syndrome?
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The detailed characterization at the molecular biology level of this novel XK splice site mutation associated with the clinical description of the patient contributes to a better understanding of the phenotype-genotype correlation in the McLeod syndrome.
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The Foxa subfamily of winged helix/forkhead box (Fox) transcription factors has been the subject of genetic and biochemical study for over 15 years. During this time its three members, Foxa1, Foxa2 and Foxa3, have been found to play important roles in multiple stages of mammalian life, beginning with early development, continuing during organogenesis, and finally in metabolism and homeostasis in the adult. Foxa2 is required for the formation of the node and notochord, and in its absence severe defects in gastrulation, neural tube patterning, and gut morphogenesis result in embryonic lethality. Foxa1 and Foxa2 cooperate to establish competence in foregut endoderm and are required for normal development of endoderm-derived organs such as the liver, pancreas, lungs, and prostate. In post-natal life, members of the Foxa family control glucose metabolism through the regulation of multiple target genes in the liver, pancreas, and adipose tissue. Insight into the unique molecular basis of Foxa function has been obtained from recent genetic and genomic data, which identify the Foxa proteins as 'pioneer factors' whose binding to promoters and enhancers enable chromatin access for other tissue-specific transcription factors.
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How does Foxa transcription factor exhibits its pioneering function?
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Insight into the unique molecular basis of Foxa function has been obtained from recent genetic and genomic data, which identify the Foxa proteins as 'pioneer factors' whose binding to promoters and enhancers enable chromatin access for other tissue-specific transcription factors
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The SILVER locus has been mapped in the domestic cat, identifying a unique genomic location distinct from that of any known reported gene associated with silver or hypopigmentation in mammals. A demonstrated lack of linkage to SILV, the strong candidate gene for silver, led to the initiation of a genome scan utilizing 2 pedigrees segregating for silver coat color. Linkage mapping defined a genomic region for SILVER as a 3.3-Mb region, (95.87-99.21 Mb) on chromosome D2, (peak logarithm of the odds = 10.5, = 0), which displays conserved synteny to a genomic interval between 118.58 and 121.85 Mb on chromosome 10 in the human genome. In the domestic cat, mutations at the SILVER locus suppress the development of pigment in the hair, but in contrast to other mammalian silver variants, there is an apparently greater influence on the production of pheomelanin than eumelanin pigment. The mapping of a novel locus for SILVER offers much promise in identifying a gene that may help elucidate aspects of pheomelanogenesis, a pathway that has been very elusive, and illustrates the promise of the cat genome project in increasing our understanding of basic biological processes of general relevance for mammals.
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On what chromosome is the gene for "SILVER" coat color found for the domestic cat?
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Linkage mapping defined a genomic region for SILVER as a 3.3-Mb region, (95.87-99.21 Mb) on chromosome D2
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In microbial communities, bacterial populations are commonly controlled using indiscriminate, broad range antibiotics. There are few ways to target specific strains effectively without disrupting the entire microbiome and local environment. Here, we use conjugation, a natural DNA horizontal transfer process among bacterial species, to deliver an engineered CRISPR interference (CRISPRi) system for targeting specific genes in recipient Escherichia coli cells. We show that delivery of the CRISPRi system is successful and can specifically repress a reporter gene in recipient cells, thereby establishing a new tool for gene regulation across bacterial cells and potentially for bacterial population control.
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What is CRISPRi?
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We show that delivery of the CRISPRi system is successful and can specifically repress a reporter gene in recipient cells, thereby establishing a new tool for gene regulation across bacterial cells and potentially for bacterial population control.
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Bilirubin-induced neurologic dysfunction (BIND) and kernicterus has been used to describe moderate to severe neurologic dysfunction observed in children exposed to excessive levels of total serum bilirubin (TSB) during the neonatal period. Here we use a new mouse model that targets deletion of the Ugt1 locus and the Ugt1a1 gene in liver to promote hyperbilirubinemia-induced seizures and central nervous system toxicity. The accumulation of TSB in these mice leads to diffuse yellow coloration of brain tissue and a marked cerebellar hypoplasia that we characterize as kernicterus. Histologic studies of brain tissue demonstrate that the onset of severe neonatal hyperbilirubinemia, characterized by seizures, leads to alterations in myelination and glia reactivity. Kernicterus presents as axonopathy with myelination deficits at different brain regions, including pons, medulla oblongata, and cerebellum. The excessive accumulation of TSB in the early neonatal period (5 days after birth) promotes activation of the myelin basic protein (Mbp) gene with an accelerated loss of MBP that correlates with a lack of myelin sheath formation. These changes were accompanied by increased astroglial and microglial reactivity, possibly as a response to myelination injury. Interestingly, cerebellum was the area most affected, with greater myelination impairment and glia burden, and showing a marked loss of Purkinje cells and reduced arborization of the remaining ones. Thus, kernicterus in this model displays not only axonal damage but also myelination deficits and glial activation in different brain regions that are usually related to the neurologic sequelae observed after severe hyperbilirubinemia.
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Which are the main brain dysfunctions caused by hyperbilirubinemia?
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Thus, kernicterus in this model displays not only axonal damage but also myelination deficits and glial activation in different brain regions that are usually related to the neurologic sequelae observed after severe hyperbilirubinemia.
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The order of genes in eukaryotic genomes has generally been assumed to be neutral, since gene order is largely scrambled over evolutionary time. Only a handful of exceptional examples are known, typically involving deeply conserved clusters of tandemly duplicated genes (e.g., Hox genes and histones). Here we report the first systematic survey of microsynteny conservation across metazoans, utilizing 17 genome sequences. We identified nearly 600 pairs of unrelated genes that have remained tightly physically linked in diverse lineages across over 600 million years of evolution. Integrating sequence conservation, gene expression data, gene function, epigenetic marks, and other genomic features, we provide extensive evidence that many conserved ancient linkages involve (1) the coordinated transcription of neighboring genes, or (2) genomic regulatory blocks (GRBs) in which transcriptional enhancers controlling developmental genes are contained within nearby bystander genes. In addition, we generated ChIP-seq data for key histone modifications in zebrafish embryos, which provided further evidence of putative GRBs in embryonic development. Finally, using chromosome conformation capture (3C) assays and stable transgenic experiments, we demonstrate that enhancers within bystander genes drive the expression of genes such as Otx and Islet, critical regulators of central nervous system development across bilaterians. These results suggest that ancient genomic functional associations are far more common than previously thought-involving ∼12% of the ancestral bilaterian genome-and that cis-regulatory constraints are crucial in determining metazoan genome architecture.
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How are GRBs (Genomic Regulatory Blocks) defined?
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Integrating sequence conservation, gene expression data, gene function, epigenetic marks, and other genomic features, we provide extensive evidence that many conserved ancient linkages involve (1) the coordinated transcription of neighboring genes, or (2) genomic regulatory blocks (GRBs) in which transcriptional enhancers controlling developmental genes are contained within nearby bystander genes.
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Genome-wide association studies (GWAS) have been highly informative in discovering disease-associated loci but are not designed to capture all structural variations in the human genome. Using long-read sequencing data, we discovered widespread structural variation within SINE-VNTR- (SVA) elements, a class of great ape-specific transposable elements with gene-regulatory roles, which represents a major source of structural variability in the human population. We highlight the presence of structurally variable SVAs (SV-SVAs) in neurological disease-associated loci, and we further associate SV-SVAs to disease-associated SNPs and differential gene expression using luciferase assays and expression quantitative trait loci data. Finally, we genetically deleted SV-SVAs in the and Alzheimer's disease-associated risk loci and in the Parkinson's disease-associated risk locus and assessed multiple aspects of their gene-regulatory influence in a human neuronal context. Together, this study reveals a novel layer of genetic variation in transposable elements that may contribute to identification of the structural variants that are the actual drivers of disease associations of GWAS loci.
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What are genome-wide association studies (GWAS)?
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Genome-wide association studies (GWAS) have been highly informative in discovering disease-associated loci but are not designed to capture all structural variations in the human genome.
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Culture-independent techniques such as LC-MS/MS-based metaproteomic analyses are being increasingly utilized for the study of microbial composition and function in complex environmental samples. Although several studies have documented the many challenges and sources of bias that must be considered in these types of analyses, none have systematically characterized the effect of protein extraction bias on the biological interpretation of true environmental biofilm metaproteomes. In this study, we compared three protein extraction methods commonly used in the analyses of environmental samples [guanidine hydrochloride (GuHCl), B-PER, sequential citrate-phenol (SCP)] using nano-LC-MS/MS and an environmental marine biofilm to determine the unique biases introduced by each method and their effect on the interpretation of the derived metaproteomes. While the protein extraction efficiencies of the three methods ranged from 2.0 to 4.3%, there was little overlap in the sequence (1.9%), function (8.3% of total assigned protein families) and origin of the identified proteins from each extract. Each extraction method enriched for different protein families (GuHCl - photosynthesis, carbohydrate metabolism; B-PER - membrane transport, oxidative stress; SCP - calcium binding, structural) while 23.7-45.4% of the identified proteins lacked SwissProt annotations. Taken together, the results demonstrated that even the most basic interpretations of this complex microbial assemblage (species composition, ratio of prokaryotic to eukaryotic proteins, predominant functions) varied with little overlap based on the protein extraction method employed. These findings demonstrate the heavy influence of protein extraction on biofilm metaproteomics and provide caveats for the interpretation of such data sets when utilizing single protein extraction methods for the description of complex microbial assemblages.
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Define marine metaproteomics
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Culture-independent techniques such as LC-MS/MS-based metaproteomic analyses are being increasingly utilized for the study of microbial composition and function in complex environmental samples.
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Although the ABO blood group of the human host has been reported to influence malarial infection, there have been few clinical observations on this effect. A hospital-based, comparative study was therefore performed to investigate the relationship between blood-group type and severe disease i nPlasmodium falciparum malaria. Overall, 243 cases of malaria (163 uncomplicated and 80 severe) and 65 patients with severe, non-malarial infections were studied. In terms of ABO-blood-group composition, the patients with severe malaria were significantly different from the patients with the uncomplicated disease (P<0.001) and also from a population control described previously (P<0.0001). The patients with uncomplicated malaria or severe but non-malarial disease were, however, similar to the population control. The cases of severe malaria were significantly less likely to be of blood group O (P=0.0003), and significantly more likely to be of group AB (P<0.0001), than the patients with nonsevere malaria. It appears that individuals who are of blood-group O are relatively resistant to the severe disease caused by P. falciparum infection.
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Are people with blood group O protected against severe Malaria?
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It appears that individuals who are of blood-group O are relatively resistant to the severe disease caused by P. falciparum infection.
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Extrapolating the figures from a previous study on FSHD in a province of The Netherlands to the entire Dutch population suggests that at present a nearly complete overview is obtained of all symptomatic kindred. In 139 families, dominant inheritance was observed in 97, a pattern compatible with germline mosaicism in 6, while sporadic cases were found in 36 families. A mutation frequency of 9.6% was calculated. Mental retardation and severe retinal vasculopathy were reported in low frequencies (1%). Early onset was seen more frequently in sporadic cases. Chromosome 4 linkage appeared excluded in 3 of 22 autosomal-dominant families. The clinical pictures in the linked and nonlinked families were identical.
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What is the mode of inheritance of Facioscapulohumeral muscular dystrophy (FSHD)?
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In 139 families, dominant inheritance was observed in 97, a pattern compatible with germline mosaicism in 6, while sporadic cases were found in 36 families.
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Human cystatin C (HCC) is a low molecular weight member of the cystatin family (type2). HCC consists of 120 amino acids. Normally it is an inhibitor of cysteine proteases, but in pathological conditions it forms amyloid fibrils in brain arteries of young adults. An 'aggregation-prone' pentapeptide ((47)LQVVR(51)) was located within the HCC sequence using AmylPred, an 'aggregation-prone' peptide prediction algorithm developed in our lab. This peptide was synthesized and self-assembled into amyloid-like fibrils in vitro, as electron microscopy, X-ray fiber diffraction, Attenuated Total Reflectance Fourier-Transform Spectroscopy and Congo red staining studies reveal. Thus, the (47)LQVVR(51) peptide seems to have an important role in HCC fibrillization.
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Which peptide plays a pivotal role in human cystatin C fibrillization?
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Thus, the (47)LQVVR(51) peptide seems to have an important role in HCC fibrillization.
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Chronic cerebrospinal venous insufficiency (CCSVI) is a syndrome characterized by stenosies of the internal jugular and/or azygous veins (IJVs-AZ) with opening of collaterals and insufficient drainage proved by reduced cerebral blood flow and increased mean transit time in cerebral MRI perfusional study. The present review is aimed to give a comprehensive overview of the actual status of the art of the diagnosis and treatment of this condition. As far as the origin of venous narrowing is concerned, phlebographic studies of the IJVs and AZ systems demonstrated that venous stenoses were likely to be truncular venous malformations; mostly, they are intraluminal defects such as malformed valve, septa webs. CCSVI condition has been found to be strongly associated with multiple sclerosis (MS), a disabling neurodegenerative and demyelinating disease considered autoimmune in nature. In several epidemiological observations performed at different latitudes on patients with different genetic backgrounds, the prevalence of CCSVI in MS ranges from 56% to 100%. To the contrary, by using venous MR and/or different Doppler protocols, CCSVI was not detected with the same prevalence. Two pilot studies demonstrated the safety and feasibility in Day Surgery of the endovascular treatment of CCSVI by means of balloon angioplasty (PTA). It determines a significant reduction of postoperative venous pressure. Restenosis rate was found out elevated in the IJVs, but negligible in the AZ. However, PTA seems to positively influence clinical and QoL parameters of the associated MS and warrants further randomized control trials.
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What is the role of venous angioplasty in multiple sclerosis?
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However, PTA seems to positively influence clinical and QoL parameters of the associated MS and warrants further randomized control trials.
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The authors report a female presenting with congenital heart defects, liver hemangiomas, and facial dysmorphisms admitted to hospital at 3 months of age because of feeding difficulties and poor growth. She had hypotonia and large tongue, "coarse" face, and umbilical hernia in presence of complex congenital cardiovascular malformations. In spite of normal neonatal screening we performed serum levels of thyroid hormones. Thyrotropin level was very high (>50 microU/ml; normal value 0.2-4 microU/ml), while serum free T(3) (FT3) and free T(4) (FT4) levels were normal (FT3 3.6 pg/ml, normal value 2.8-5.6 pg/ml; FT4 11.6 pg/ml, normal value 6.6-14 pg/ml); antithyroid autoantibodies were absent. Thyroid scintigraphy with sodium 99m Tc pertechnetate showed a small ectopic thyroid located in sublingual position, so treatment with L-thyroxine 37.5 microg/24 hr was started with rapid improvement of the clinical picture. At 17 months of age the patient developed the complete characteristic phenotype of Williams syndrome (WS); the clinical diagnosis was proven by fluorescent in situ hybridization (FISH) analysis which showed hemizygous deletion of the elastin gene on chromosome 7. Recently a case of thyroid hemiagenesis in a child with WS has been reported; our patient underscores the association of hypothyroidism and WS. Moreover, our case shows that clinical manifestations of hypothyroidism may be present and the treatment may be necessary as it is in isolated congenital hypothyroidism.
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Which hormone abnormalities are common in Williams syndrome ?
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Recently a case of thyroid hemiagenesis in a child with WS has been reported; our patient underscores the association of hypothyroidism and WS.
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Anemia is common and associated with adverse outcomes in children with chronic kidney disease (CKD). Many factors contribute to declining hemoglobin as CKD progresses, but impaired production of erythropoietin by failing kidneys is a central cause. Hepcidin-mediated iron restriction also contributes to anemia by downregulating both intestinal iron absorption and release of stored iron for erythropoiesis. The core components of anemia management remain erythropoiesis-stimulating agents (ESA) and iron supplementation, but despite these therapies, a substantial number of children remain anemic. Although escalating ESA dose to target higher hemoglobin has been associated with adverse outcomes in adults, no trials have investigated this association in children, and maintaining hemoglobin levels in a narrow range with conservative ESA dosing is challenging. Judicious use of iron supplementation can enhance the response to ESAs, but the iron storage markers most commonly used in clinical practice have limitations in distinguishing which patients will benefit most from additional iron. Several novel anemia therapies, including hypoxia-inducible factor stabilizers, prolyl hydroxylase inhibitors, and dialysate-delivered iron supplements, have been developed and may offer options for alternative anemia management. However, the safety and efficacy of these agents in children with CKD has yet to be assessed.
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Is Iron deficiency anemia a common complication of chronic kidney disease?
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nemia is common and associated with adverse outcomes in children with chronic kidney disease (CKD
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We were able to detect AMLAs in four children with recurrent pericarditis. This finding may be attributed to an auto-immunological disease following a first, acute event. We propose the detection of AMLAs in all children with unexplained recurrent pericarditis. Pediatric patients with a persistence of IgM-type AMLAs may face frequent recurrences and should be monitored therefore more closely. In addition, medical treatment may be changed in these patients with a slower tapering of the dosage of steroidal and non-steroidal antiinflammatory drugs.
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What is the treatment of acute pericarditis?
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medical treatment may be changed in these patients with a slower tapering of the dosage of steroidal and non-steroidal antiinflammatory drugs.
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Heterogeneity of major depressive disorder (MDD) illness course complicates clinical decision-making. Although efforts to use symptom profiles or biomarkers to develop clinically useful prognostic subtypes have had limited success, a recent report showed that machine-learning (ML) models developed from self-reports about incident episode characteristics and comorbidities among respondents with lifetime MDD in the World Health Organization World Mental Health (WMH) Surveys predicted MDD persistence, chronicity and severity with good accuracy. We report results of model validation in an independent prospective national household sample of 1056 respondents with lifetime MDD at baseline. The WMH ML models were applied to these baseline data to generate predicted outcome scores that were compared with observed scores assessed 10-12 years after baseline. ML model prediction accuracy was also compared with that of conventional logistic regression models. Area under the receiver operating characteristic curve based on ML (0.63 for high chronicity and 0.71-0.76 for the other prospective outcomes) was consistently higher than for the logistic models (0.62-0.70) despite the latter models including more predictors. A total of 34.6-38.1% of respondents with subsequent high persistence chronicity and 40.8-55.8% with the severity indicators were in the top 20% of the baseline ML-predicted risk distribution, while only 0.9% of respondents with subsequent hospitalizations and 1.5% with suicide attempts were in the lowest 20% of the ML-predicted risk distribution. These results confirm that clinically useful MDD risk-stratification models can be generated from baseline patient self-reports and that ML methods improve on conventional methods in developing such models.
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Have machine learning methods been used to predict the severity of major depressive disorder(MDD)?
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These results confirm that clinically useful MDD risk-stratification models can be generated from baseline patient self-reports and that ML methods improve on conventional methods in developing such models
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We sought to determine whether mirtazapine is safe and well-tolerated as a treatment for essential tremor (ET). We studied mirtazapine in a randomized, double-blind, placebo-controlled, crossover study of 17 ET patients. Patients were started with 15 mg per day of either mirtazapine or placebo for 1 week and the dose was escalated weekly until the targeted dose of 45 mg per day was achieved. This dose was maintained for 2 weeks. Tremor was assessed at baseline and after 14 days of 45 mg of mirtazapine or placebo. There was a minimum washout period of 14 days between the two arms of the study. Tremor assessments included global improvement, Fahn Tolosa Marin Tremor Rating Scale, Beck Depression Inventory and the Parkinson's Disease Questionnaire-39. Patient global improvement ratings indicated that in the placebo condition 12 patients were unchanged and 1 patient was mildly improved. In the mirtazapine condition, 10 patients were unchanged, 2 were moderately improved and 1 was markedly improved. There was no significant improvement with mirtazapine or placebo compared to baseline as measured by the Tremor Rating Scale. Adverse effects were more common in the mirtazapine group and included drowsiness, confusion, dry mouth, weight gain, polyuria, itching, nausea, gait and balance problems, blurred vision, and bad taste. We conclude that the majority of the ET patients do not benefit from mirtazapine. Mirtazapine has significant adverse effects and should be used cautiously in ET patients.
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Which disease is rated using the Fahn-Tolosa-Marin scale?
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sessments included global improvement, Fahn Tolosa Marin Tremor Rating Scale, Beck Depression Inventory and the Parkinson's Disease Questionnaire-39. Patient globa
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Arterial tortuosity syndrome (ATS) is an autosomal recessive connective tissue disorder caused by loss-of-function mutations in SLC2A10, which encodes facilitative glucose transporter 10 (GLUT10). The role of GLUT10 in ATS pathogenesis remains an enigma, and the transported metabolite(s), i.e. glucose and/or dehydroascorbic acid, have not been clearly elucidated. To discern the molecular mechanisms underlying the ATS aetiology, we performed gene expression profiling and biochemical studies on skin fibroblasts. Transcriptome analyses revealed the dysregulation of several genes involved in TGFβ signalling and extracellular matrix (ECM) homeostasis as well as the perturbation of specific pathways that control both the cell energy balance and the oxidative stress response. Biochemical and functional studies showed a marked increase in ROS-induced lipid peroxidation sustained by altered PPARγ function, which contributes to the redox imbalance and the compensatory antioxidant activity of ALDH1A1. ATS fibroblasts also showed activation of a non-canonical TGFβ signalling due to TGFBRI disorganization, the upregulation of TGFBRII and connective tissue growth factor, and the activation of the αvβ3 integrin transduction pathway, which involves p125FAK, p60Src and p38 MAPK. Stable GLUT10 expression in patients' fibroblasts normalized redox homeostasis and PPARγ activity, rescued canonical TGFβ signalling and induced partial ECM re-organization. These data add new insights into the ATS dysregulated biological pathways and definition of the pathomechanisms involved in this disorder.
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Mutation of which gene causes arterial tortuosity syndrome?
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Arterial tortuosity syndrome (ATS) is an autosomal recessive connective tissue disorder caused by loss-of-function mutations in SLC2A10, which encodes facilitative glucose transporter 10 (GLUT10).
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Acetaldehyde (ACH) associated with alcoholic beverages is Group 1 carcinogen to humans (IARC/WHO). Aldehyde dehydrogenase (ALDH2), a major ACH eliminating enzyme, is genetically deficient in 30-50% of Eastern Asians. In alcohol drinkers, ALDH2-deficiency is a well-known risk factor for upper aerodigestive tract cancers, i.e., head and neck cancer and esophageal cancer. However, there is only a limited evidence for stomach cancer. In this study we demonstrated for the first time that ALDH2 deficiency results in markedly increased exposure of the gastric mucosa to acetaldehyde after intragastric administration of alcohol. Our finding provides concrete evidence for a causal relationship between acetaldehyde and gastric carcinogenesis. A plausible explanation is the gastric first pass metabolism of ethanol. The gastric mucosa expresses alcohol dehydrogenase (ADH) enzymes catalyzing the oxidation of ethanol to acetaldehyde, especially at the high ethanol concentrations prevailing in the stomach after the consumption of alcoholic beverages. The gastric mucosa also possesses the acetaldehyde-eliminating ALDH2 enzyme. Due to decreased mucosal ALDH2 activity, the elimination of ethanol-derived acetaldehyde is decreased, which results in its accumulation in the gastric juice. We also demonstrate that ALDH2 deficiency, proton pump inhibitor (PPI) treatment, and L-cysteine cause independent changes in gastric juice and salivary acetaldehyde levels, indicating that intragastric acetaldehyde is locally regulated by gastric mucosal ADH and ALDH2 enzymes, and by oral microbes colonizing an achlorhydric stomach. Markedly elevated acetaldehyde levels were also found at low intragastric ethanol concentrations corresponding to the ethanol levels of many foodstuffs, beverages, and dairy products produced by fermentation. A capsule that slowly releases L-cysteine effectively eliminated acetaldehyde from the gastric juice of PPI-treated ALDH2-active and ALDH2-deficient subjects. These results provide entirely novel perspectives for the prevention of gastric cancer, especially in established risk groups.
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Which are the effects of ALDH2 deficiency?
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In alcohol drinkers, ALDH2-deficiency is a well-known risk factor for upper aerodigestive tract cancers, i.e., head and neck cancer and esophageal cancer.
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NKX2-1 (NK2 homeobox 1) is a critical regulator of transcription for the surfactant protein (SP)-B and -C genes (SFTPB and SFTPC, respectively). We identified and functionally characterized two new de novo NKX2-1 mutations c.493C>T (p.R165W) and c.786_787del2 (p.L263fs) in infants with closely similar severe interstitial lung disease (ILD), hypotonia, and congenital hypothyroidism. Functional analyses using A549 and HeLa cells revealed that NKX2-1-p.L263fs induced neither SFTPB nor SFTPC promoter activation and had a dominant negative effect on wild-type (WT) NKX2-1. In contrast,NKX2-1-p.R165W activated SFTPC, to a significantly greater extent than did WTNKX2-1, while SFTPB activation was only significantly reduced in HeLa cells. In accordance with our in vitro data, we found decreased amounts of SP-B and SP-C by western blot in bronchoalveolar lavage fluid (patient with p.L263fs) and features of altered surfactant protein metabolism on lung histology (patient with NKX2-1-p.R165W). In conclusion, ILD in patients with NKX2-1 mutations was associated with altered surfactant protein metabolism, and both gain and loss of function of the mutated NKX2-1 genes on surfactant protein promoters were associated with ILD in "Brain-Lung-Thyroid syndrome".
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Mutation of which gene is implicated in the Brain-lung-thyroid syndrome?
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In conclusion, ILD in patients with NKX2-1 mutations was associated with altered surfactant protein metabolism, and both gain and loss of function of the mutated NKX2-1 genes on surfactant protein promoters were associated with ILD in "Brain-Lung-Thyroid syndrome".
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Inherited distubances in skin structure and its function are the main cause of diseases classified as genodermatoses. The following clinical entities are classified as genodermatoses: epidermolysis bullosa, keratotic disorders, disorders of skin color, ectodermal genodermatoses, genodermatoses associated with connective tissue, vascular genodermatoses and genodermatoses with skin manifestation and elevated cancer risk. One of the most clinically heterogenous group of genodermatoses, is epidermolysis bullosa. Four main subtypes were described: simplex, dystrophic, junctional and Kindler syndrome. These diseases are caused by mutations in the genes encoding proteins forming junctions between the dermis and epidermis (eg. COL7A1, COL17A1, KRT14, KRT5 or genes coding for 332 laminin). They are inherited in an autosomal recessive or dominant manner. The disease that is inherited as a dominant, sex dependent trait, is incontinenia pigmenti (Bloch-Sulzberger syndrome) characterized by the presence of extensive pigmentation changes already in the neonatal period. In patients with incontinenia pigmenti, mutations in the NEMO gene are found. The protein encoded by NEMO is involved in the negative regulation of activity of the NFκB transcription factor that is responsible for apoptosis and cell proliferation control. In the regulation of cell proliferation, the neurofibromin (NF1) - the suppressor of RAS/MAPK signaling pathway activity, is also involved. The mutations in the NF1 gene are identified in neurofibromatosis type I - a genodermatosis with higher risk of cancer development and tumor formation. Herein, a review of selected genodermatoses in the context of their molecular pathology is presented.
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Which inherited disorder is known to be caused by mutations in the NEMO gene?
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In patients with incontinenia pigmenti, mutations in the NEMO gene are found
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The purpose of this study was the assessment of the feasibility of dynamic positron emission tomography (PET) studies with fluorine-18 fluorodeoxyglucose ((18)F-FDG) to quantify effects of the cyclic Arg-Gly-Asp peptide cilengitide, which targets the ανβ 3 and ανβ 5 integrin receptors in rats with breast cancer bone metastases. Rats were inoculated with MDA-MB-231 breast cancer cells, followed by the development of lytic lesions in the hind leg. Rats with lytic lesions were treated with cilengitide five times weekly on a continuous basis from days 30 to 55 after tumor cell inoculation. Dynamic PET studies with (18)F-FDG were performed in untreated (n=9), controlled (n=4) and treated rats (n=6). The data were assessed using learning-machine two-tissue compartmental analysis. The (18)F-FDG kinetic parameters obtained by two-tissue compartmental model learning-machine showed significant differences when individual parameters were compared between the control group and treated animals. Quantitative assessment of the tracer kinetics and the application of classification analysis to the data provided us with evidence to identify those tumors that demonstrated effect of cilengitide treatment. The transport rate K1 and the phosphorylation rate k3 were significantly different (P=0.033 and 0.038, respectively). Classification analysis based on support vector machines ranking feature elimination of the combination of PET parameters revealed an overall accuracy of 80.0% between treated animals and the control group. We were able to identify 83.3% treated animals compared with the control group based on k2 and VB. In conclusion, the results revealed that cilengitide treatment of experimental breast cancer bone metastases had a significant therapeutic impact on (18)F-FDG kinetics.
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List receptors of the drug Cilengitide
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The purpose of this study was the assessment of the feasibility of dynamic positron emission tomography (PET) studies with fluorine-18 fluorodeoxyglucose ((18)F-FDG) to quantify effects of the cyclic Arg-Gly-Asp peptide cilengitide, which targets the ανβ 3 and ανβ 5 integrin receptors in rats with breast cancer bone metastases.
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McKusick-Kaufman syndrome is a rare autosomal recessive disease diagnosed by polydactyly, hydrometrocolpos, and congenital heart disease. We present an unusual laparotomy confirmed urogenital MRI finding (atretic vaginal pouch) in a 3-month-old girl with McKusick-Kaufman syndrome. Up to our knowledge, this MR finding has not been reported in the literature yet.
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What 3 disorders are commonly associated with Kaufman-McKusick syndrome?
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McKusick-Kaufman syndrome is a rare autosomal recessive disease diagnosed by polydactyly, hydrometrocolpos, and congenital heart disease.
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Bartter syndrome (BS) is a rare renal tubular disorder presenting with hypokalemic metabolic alkalosis, which is classified into five types. KCNJ1 mutations usually cause the neonatal form of BS, type II BS (OMIM 241200). However, this report concerns a female patient with a novel, compound heterozygous KCNJ1 mutation that causes late-onset BS. The unique clinical findings of this case include persistently elevated 1,25(OH)(2) vitamin D levels, possibly due to increase prostaglandin E(2) levels, and medullary nephrocalcinosis. Treatment with COX-2 inhibitors resolved her hypercalciuria and improved her height and weight; renal function remains stable and there is no progression of nephrocalcinosis.
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What is Bartter syndrome?
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Bartter syndrome (BS) is a rare renal tubular disorder presenting with hypokalemic metabolic alkalosis, which is classified into five types
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Deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) activity is an inborn error of purine metabolism associated with uric acid overproduction and a continuum spectrum of neurological manifestations depending on the degree of enzyme deficiency. The complete deficiency causes Lesch-Nyhan syndrome (LNS). Partial HPRT-deficient patients can show a variable degree of neurological manifestations. Both diseases have been associated with mutations in the HPRT1 gene. Documented mutations in HPRT deficiency show a high degree of heterogeneity in type and location within the gene. In fact, more than 300 disease-associated mutations have been described. Splice mutations accounts for more that 16% of HPRT mutations and in most cases cause a complete LNS phenotype. A 16 year-old boy consulted to La Paz University Hospital because of hyperuricemia (9.4 mg/dL). At age one year he was given a diagnosis of dystonic cerebral palsy. Although he usually employs a wheelchair, under certain circumstances, he is able to stand up and walk by himself. He has never showed self injurious behavior. This patient presented a splice mutation (NM_000194.2: c.552 -2 A > G) causing exon 5 exclusion. An exon-5 specific PCR was designed, and a minor amount of normally spliced HPRT mRNA was found. Normally spliced HPRT mRNA was quantified by real-time PCR in this patient, in control subjects, and in two Lesch Nyhan patient with splice mutations excluding exon 4 (patient B) and exon 8 (patient C) who had clinically a Lesch Nyhan disease phenotype. A minor amount of normally spliced HPRT mRNA was found in all the patients. No correlation was found between the percentage of the normally spliced HPRT mRNA and the phenotype. We conclude that the partial HPRT deficient phenotype of this patient can not be explained by the finding of a minor amount of normally splice HPRT mRNA. It is possible that the amount of normally splice mRNA vary among different tissues.
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Which gene has been found to be mutant in Lesch-Nyhan Disease patients?
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Normally spliced HPRT mRNA was quantified by real-time PCR in this patient, in control subjects, and in two Lesch Nyhan patient with splice mutations excluding exon 4 (patient B) and exon 8 (patient C) who had clinically a Lesch Nyhan disease phenotype.
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Gliomas are the most common type of brain cancer in the pediatric patients, constituting about 50% of all childhood intracranial tumors. This is a highly heterogeneous group, varying from the benign WHO histopathological grades I and II to malignant WHO grades III and IV. The histology and location are significant prognostic factors, which influence the decision for surgical intervention, as well as the extent of possible tumor removal. In low-grade gliomas, surgery remains the initial option and should be directed at gross total resection in favorable locations, such as the cerebral hemispheres and the cerebellum. Management of high-grade gliomas (HGG), which are less common in children compared to adults, continue to pose a significant challenge. In non-brainstem HGG, the goal is safe maximal tumor removal, while it generally does not play any role in diffuse intrinsic pontine gliomas. Treatment must, thus, be individualized in the majority of cases of HGG. Surgery for gliomas in children continues to be aided by technological advancements facilitating tumor resection and improving patient safety and outcomes.
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What is the most common pediatric glioma?
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Gliomas are the most common type of brain cancer in the pediatric patients, constituting about 50% of all childhood intracranial tumors.
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A retrospective study in which we reviewed the hospital files of a subset of 7 patients with Duchenne muscular dystrophy participating in the open-label phase I/II PRO051-02 study in Leuven. The objective of this study was to describe in detail the injection site reactions in these children treated with drisapersen (PRO-051), a 2'-O-methyl phosphorothioate RNA antisense oligonucleotide, that induces exon 51 skipping in Duchenne muscular dystrophy. Antisense oligonucleotides, restoring the reading frame by skipping of exons, have become a potential treatment of Duchenne muscular dystrophy and other monogenetic diseases. Erythema followed by hyperpigmentation, fibrosis, and calcification were seen at the injection sites in all children. Ulcerations, which were difficult to heal, occurred in 5 of 7 children. Progression still occurred after switching to intravenous administration of drisapersen or even after stopping therapy. Systemic reactions included a reversible proteinuria and α1-microglobulinuria. Moreover, hypotrichosis was a common feature.Conclusion: Subcutaneous administration of drisapersen causes severe and progressive injection site effects. What is known: • Antisense oligonucleotides offer the possibility to convert Duchenne muscular dystrophy to the less severe Becker type. This can potentially be achieved by targeting and skipping specific exons of the Duchenne muscular dystrophy gene to restore the disrupted reading frame and to induce the production of a semi functional dystrophin protein. • Drisapersen is such an antisense oligonucleotides which can be administered subcutaneously. Its use has been tested extensively in the escalating dose pilot study (PRO051-02). What is new: • This report describes the injection site reactions caused by this type of agent in detail which has never been done before. We therefore reviewed the hospital files of 7 patients with Duchenne muscular dystrophy participating in the phase I/II open-label, escalating dose pilot study (PRO051-02) with drisapersen. • Severe side effects starting with erythema, hyperpigmentation, and later fibrosis, calcification, and difficult to treat ulcerations developed in all patients, and these continued to progress even after cessation of drisapersen. We discuss some possible underlying mechanisms. The exact mechanism however is still not known.
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What datasets are available related to Duchenne Muscular Dystrophy?
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in the escalating dose pilot study (PRO051-02)
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Genital herpes is the most prevalent sexually transmitted infection in the USA. While sometimes mild in severity, it can be a distressing and painful chronic condition. Likewise, herpes labialis and herpes zoster can be both physically and psychologically painful. While there is no cure for these conditions, treatment to alleviate symptoms, suppress recurrences and reduce transmission has been drastically improved over the past 20 years with the use of guanine nucleoside antivirals, such as valacyclovir hydrochloride (Valtrex), GlaxoSmithKline) the highly bioavailable prodrug of acyclovir (Zovirax((R)), GlaxoSmithKline), and famciclovir (Famvir, Novartis), a highly bioavailable prodrug of penciclovir (Denavir, Novartis). Clinical trials involving approximately 10,000 patients (including patients from nongenital herpes studies, such as herpes zoster) have assessed the safety and efficacy of valacyclovir in the treatment of initial genital herpes outbreaks, episodic treatment of recurrent episodes and daily suppressive therapy. It was shown that valacyclovir has similar efficacy to acyclovir in the episodic and suppressive treatment of genital herpes. Valacyclovir is the only antiviral drug approved for a once-daily dose of suppressive therapy for genital herpes, as well as the only antiviral drug US FDA approved for a 3-day regimen of episodic treatment of recurrent genital herpes. In addition, valacyclovir is also indicated in the reduction of the sexual transmission of herpes simplex virus infection and for the treatment of herpes labialis. In herpes zoster, valacyclovir is more effective than acyclovir or placebo (and as equally effective as famciclovir) in shortening the length and severity of herpes zoster-associated pain and postherpetic neuralgia. Valacyclovir has an acceptable safety profile in patients with herpes simplex and herpes zoster. The less frequent dosing regimen makes it an attractive option in the treatment of genital herpes and other viral infections, and may contribute to increased patient adherence to therapy.
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Please list 3 diseases treated with Valtrex(valacyclovir)
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alacyclovir is the only antiviral drug approved for a once-daily dose of suppressive therapy for genital herpes, as well as the only antiviral drug US FDA approved for a 3-day regimen of episodic treatment of recurrent genital herpes.
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Live oral rotavirus vaccine strain RIT 4237, derived from group A bovine rotavirus NCDV, was given to human volunteers in Tampere, Finland in 1982. Efficacy studies of this vaccine in 6-12 month-old children gave results characteristic of the performance of oral rotavirus vaccines in general: 58% protective efficacy against any rotavirus gastroenteritis and 82% against "clinically significant" gastroenteritis. Four trials of RIT 4237 bovine rotavirus vaccine, one trial of group A RRV-1 rhesus rotavirus vaccine, and one trial of rhesus-human reassortant rotavirus vaccines D x RRV and DS1 x RRV were carried out between 1983-1989. A meta-analysis of the protective efficacy of these vaccines indicated a 67% (95% C.I. 55-77%) efficacy against moderately severe rotavirus disease and an 81% (95% C.I. 60-91%) efficacy against severe rotavirus disease. There was no apparent difference between bovine and rhesus-based rotavirus vaccines in the protective efficacy against severe rotavirus gastroenteritis. Problems associated with the use of any oral rotavirus vaccine include acid lability of the vaccine virus, which requires buffering, and a slight but significant interference of oral poliovirus vaccine with the uptake of rotavirus vaccine. In the near future, oral heterologous rotavirus vaccines may be available for prevention of severe rotavirus gastroenteritis.
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Is there a vaccine for rotavirus?
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Live oral rotavirus vaccine strain RIT 4237, derived from group A bovine rotavirus NCDV, was given to human volunteers in Tampere, Finland in 1982.
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Diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy, indicating that the interplay between autophagy and apoptotic cell death pathways is important in the pathogenesis of diabetic cardiomyopathy. The potential mechanism, however, remains unknown. We recently reported that diabetes depresses AMP-activated protein kinase (AMPK) activity, inhibits MAPK8/JNK1-BCL2 signaling, and promotes the interaction between BECN1 and BCL2. Concomitantly, diabetes induces cardiomyocyte apoptosis and suppresses cardiac autophagy. Activation of AMPK directly phosphorylates MAPK8, which mediates BCL2 phosphorylation and subsequent BECN1-BCL2 dissociation, leading to restoration of cardiac autophagy, protection against cardiac apoptosis, and ultimately improvement in cardiac structure and function. We conclude that dissociation of BCL2 from BECN1 through activation of MAPK8-BCL2 signaling may be an important mechanism by which AMPK activation restores autophagy, protects against cardiac apoptosis, and prevents diabetic cardiomyopathy.
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What is the role of AMPK in diabetic cardiomyopathy?
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We recently reported that diabetes depresses AMP-activated protein kinase (AMPK) activity, inhibits MAPK8/JNK1-BCL2 signaling
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Forkhead box O (FOXO) transcription factors are involved in various cellular processes, including cell proliferation, stress resistance, metabolism, and longevity. Regulation of FOXO transcriptional activity occurs mainly through a variety of post-translational modifications, including phosphorylation, acetylation, and ubiquitination. Here we describe nemo-like kinase (NLK) as a novel regulator of FOXOs. NLK binds to and phosphorylates FOXO1, FOXO3a, and FOXO4 on multiple residues. NLK acts as a negative regulator of FOXO transcriptional activity. For FOXO4 we show that NLK-mediated loss of FOXO4 activity co-occurs with inhibition of FOXO4 monoubiquitination. Previously, we have shown that oxidative stress-induced monoubiquitination of FOXO4 stimulates its transactivation, which leads to activation of an antioxidant defensive program. Conversely, NLK-dependent inhibition of FOXO4 activity can provide a means to downregulate this defensive program, when oxidative stress reaches a level beyond which repair is no longer feasible and cells need to undergo apoptosis.
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Can FOXOs modulate longevity?
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Forkhead box O (FOXO) transcription factors are involved in various cellular processes, including cell proliferation, stress resistance, metabolism, and longevity
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Mechanistic studies in erythroid cells indicate that LDB1, as part of a GATA1/TAL1/LMO2 complex, brings erythroid-expressed genes into proximity with enhancers for transcription activation. The role of co-activators in establishing this long-range interaction is poorly understood. Here we tested the contributions of the RNA Pol II pre-initiation complex (PIC), mediator and cohesin to establishment of locus control region (LCR)/β-globin proximity. CRISPR/Cas9 editing of the β-globin promoter to eliminate the RNA Pol II PIC by deleting the TATA-box resulted in loss of transcription, but enhancer-promoter interaction was unaffected. Additional deletion of the promoter GATA1 site eliminated LDB1 complex and mediator occupancy and resulted in loss of LCR/β-globin proximity. To separate the roles of LDB1 and mediator in LCR looping, we expressed a looping-competent but transcription-activation deficient form of LDB1 in LDB1 knock down cells: LCR/β-globin proximity was restored without mediator core occupancy. Further, Cas9-directed tethering of mutant LDB1 to the β-globin promoter forced LCR loop formation in the absence of mediator or cohesin occupancy. Moreover, ENCODE data and our chromatin immunoprecipitation results indicate that cohesin is almost completely absent from validated and predicted LDB1-regulated erythroid enhancer-gene pairs. Thus, lineage specific factors largely mediate enhancer-promoter looping in erythroid cells independent of mediator and cohesin.
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Is LDB1-mediated enhancer looping dependent on cohesin?
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Moreover, ENCODE data and our chromatin immunoprecipitation results indicate that cohesin is almost completely absent from validated and predicted LDB1-regulated erythroid enhancer-gene pairs.
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Patients with coronavirus disease 2019 (COVID-19) have elevated D-dimer levels. Early reports describe high venous thromboembolism (VTE) and disseminated intravascular coagulation (DIC) rates, but data are limited. This multicenter retrospective study describes the rate and severity of hemostatic and thrombotic complications of 400 hospital-admitted COVID-19 patients (144 critically ill) primarily receiving standard-dose prophylactic anticoagulation. Coagulation and inflammatory parameters were compared between patients with and without coagulation-associated complications. Multivariable logistic models examined the utility of these markers in predicting coagulation-associated complications, critical illness, and death. The radiographically confirmed VTE rate was 4.8% (95% confidence interval [CI], 2.9-7.3), and the overall thrombotic complication rate was 9.5% (95% CI, 6.8-12.8). The overall and major bleeding rates were 4.8% (95% CI, 2.9-7.3) and 2.3% (95% CI, 1.0-4.2), respectively. In the critically ill, radiographically confirmed VTE and major bleeding rates were 7.6% (95% CI, 3.9-13.3) and 5.6% (95% CI, 2.4-10.7), respectively. Elevated D-dimer at initial presentation was predictive of coagulation-associated complications during hospitalization (D-dimer >2500 ng/mL, adjusted odds ratio [OR] for thrombosis, 6.79 [95% CI, 2.39-19.30]; adjusted OR for bleeding, 3.56 [95% CI, 1.01-12.66]), critical illness, and death. Additional markers at initial presentation predictive of thrombosis during hospitalization included platelet count >450 × 109/L (adjusted OR, 3.56 [95% CI, 1.27-9.97]), C-reactive protein (CRP) >100 mg/L (adjusted OR, 2.71 [95% CI, 1.26-5.86]), and erythrocyte sedimentation rate (ESR) >40 mm/h (adjusted OR, 2.64 [95% CI, 1.07-6.51]). ESR, CRP, fibrinogen, ferritin, and procalcitonin were higher in patients with thrombotic complications than in those without. DIC, clinically relevant thrombocytopenia, and reduced fibrinogen were rare and were associated with significant bleeding manifestations. Given the observed bleeding rates, randomized trials are needed to determine any potential benefit of intensified anticoagulant prophylaxis in COVID-19 patients.
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What are the major thrombotic complications in patients with COVID-19?
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The radiographically confirmed VTE rate was 4.8% (95% confidence interval [CI], 2.9-7.3), and the overall thrombotic complication rate was 9.5% (95% CI, 6.8-12.8). The overall and major bleeding rates were 4.8% (95% CI, 2.9-7.3) and 2.3% (95% CI, 1.0-4.2), respectively. In the critically ill, radiographically confirmed VTE and major bleeding rates were 7.6% (95% CI, 3.9-13.3) and 5.6% (95% CI, 2.4-10.7), respectively.
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Cardiorenal syndromes (CRS) have been subclassified as five defined entities which represent clinical circumstances in which both the heart and the kidney are involved in a bidirectional injury and dysfunction via a final common pathway of cell-to-cell death and accelerated apoptosis mediated by oxidative stress. Types 1 and 2 involve acute and chronic cardiovascular disease (CVD) scenarios leading to acute kidney injury or accelerated chronic kidney disease. Types 2 and 3 describe acute and chronic kidney disease leading primarily to heart failure, although it is possible that acute coronary syndromes, stroke, and arrhythmias could be CVD outcomes in these forms of CRS. Finally, CRS type 5 describes a simultaneous insult to both heart and kidneys, such as sepsis, where both organs are injured simultaneously. Both blood and urine biomarkers are reviewed in this paper and offer a considerable opportunity to enhance the understanding of the pathophysiology and known epidemiology of these recently defined syndromes.
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Are there any urine biomarkers for chronic kidney disease?
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Both blood and urine biomarkers are reviewed in this paper and offer a considerable opportunity to enhance the understanding of the pathophysiology and known epidemiology of these recently defined syndromes.
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Tecovirimat (TPOXX) is an orthopoxvirus-specific antiviral drug developed by SIGA Technologies in conjunction with the US Department of Health and Human Services' Biomedical Advances Research and Development Authority. It acts by inhibiting the activity of the orthopoxvirus VP37 envelope wrapping protein, thereby preventing the formation of egress-competent enveloped virions, which are essential for dissemination of the virus in the host. In July 2018, oral tecovirimat was approved in the USA for the treatment of human smallpox disease caused by variola virus in adults and paediatric patients weighing ≥ 13 kg. Tecovirimat was approved under the US FDA's Animal Rule, in which marketing approval is based on its efficacy in relevant animal models. An intravenous formulation of tecovirimat is undergoing phase I development for the treatment of smallpox infection. This article summarises the milestones in the development of tecovirimat leading to this first approval for the treatment of human smallpox disease in adults and paediatric patients weighing ≥ 13 kg.
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Is Tecovirimat effective for smallpox?
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An intravenous formulation of tecovirimat is undergoing phase I development for the treatment of smallpox infection.
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We report here the initial examination of volatile organic compounds (VOCs) emanating from human earwax (cerumen). Recent studies link a single nucleotide polymorphism (SNP) in the adenosine triphosphate (ATP) binding cassette, sub-family C, member 11 gene (ABCC11) to the production of different types of axillary odorants and cerumen. ABCC11 encodes an ATP-driven efflux pump protein that plays an important function in ceruminous apocrine glands of the auditory canal and the secretion of axillary odor precursors. The type of cerumen and underarm odor produced by East Asians differ markedly from that produced by non-Asians. In this initial report we find that both groups emit many of the same VOCs but differ significantly in the amounts produced. The principal odorants are volatile organic C2-to-C6 acids. The physical appearance of cerumen from the two groups also matches previously reported ethnic differences, viz., cerumen from East Asians appears dry and white while that from non-Asians is typically wet and yellowish-brown.
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Which gene controls the consistency of cerumen (ear wax)?
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Recent studies link a single nucleotide polymorphism (SNP) in the adenosine triphosphate (ATP) binding cassette, sub-family C, member 11 gene (ABCC11) to the production of different types of axillary odorants and cerumen
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The Schizosaccharomyces pombe centromere-linked genes, LYS1 and CYH1 on chromosome I and TPS13 and RAN1 on chromosome II, have been isolated. The genetic order of these markers with respect to their centromeres was determined to establish relative directionality on the genetic and physical maps. Chromosome walking toward the centromeres reveals a group of repetitive sequences that occur only in the centromere regions of chromosomes I and II and at one other specific location in the S. pombe genome, presumably the centromere of chromosome III. The major class of large repeated sequence elements is 6.4 kilobases (kb) long (repeat K), portions of which occur at least twice on chromosome II and in several tandemly arranged intact copies at another centromeric location. Repeat K in turn contains groups of smaller repeats. Genetic recombination is strongly suppressed in the centromere II region, which contains at least 30 kb of repeated sequences. Centromeric DNA organization is much more complex in fission yeast than has been described in budding yeast (Saccharomyces cerevisiae), possibly because of the larger more condensed nature of the S. pombe chromosomes.
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Which protein complexes recognize centromeric (CEN) DNA in yeast?
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The Schizosaccharomyces pombe centromere-linked genes, LYS1 and CYH1 on chromosome I and TPS13 and RAN1 on chromosome II, have been isolated
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Interaction between CXCR4 and CXCL12 plays a role in tumor progression. The present study examined CXCR4, CXCL12 and CD133 expression in liver metastases of colorectal cancer (CLM) and determined whether the expression profiles affect the tumor microenvironment and thus progression, and whether they could serve as a prognostic marker for survival. Liver metastases of colorectal cancer collected from 92 patients were evaluated by CXCR4, CXCL12 and CD133 immunohistochemistry and clinicopathological data were analyzed. The expression profile of CXCR4 was determined in the colorectal cancer cell line, SW48. The expression of cytoplasmic CXCR4 was higher in 36 (39%) patients than that indicated by CXCR4 staining intensity of hepatocytes. High levels of nuclear CXCR4 expression in 23 (25%) patients significantly correlated with CXCL12 expression in hepatocytes. Nuclear CXCR4 expression was increased in the cancer cells after exposure to CXCL12. Univariate and multivariate analyses demonstrated that the high levels of nuclear CXCR4 and CXCL12 expression in hepatocytes were significantly better prognostic factors for overall and hepatic disease-free survival in patients with CLM. The expression of CXCR4 and CXCL12 in CLM may have an interactive effect that could alter the tumor microenvironment. CXCR4 expression in metastatic liver tumors together with the upregulation of CXCL12 in hepatocytes may help to predict the clinical outcomes of patients with CLM after hepatectomy.
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Is protein CXCR4 used as a prognostic marker of cancer?
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Univariate and multivariate analyses demonstrated that the high levels of nuclear CXCR4 and CXCL12 expression in hepatocytes were significantly better prognostic factors for overall and hepatic disease-free survival in patients with CLM.
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SATB1 (special AT-rich sequence-binding protein-1) provides a key link between DNA loop organization, chromatin modification/remodeling, and association of transcription factors at matrix attachment regions (MARs). To investigate the role of SATB1 in cellular events, we performed a yeast two-hybrid screen that identified SUMO-1, Ubc9, and protein inhibitor of activated STAT (PIAS) family members as SATB1 interaction partners. These proteins, working in concert, enhanced SUMO conjugation to lysine-744 of SATB1. Overexpression of SUMO or PIAS in Jurkat cells, which express high levels of endogenous SATB1, exhibited enhanced caspase cleavage of this MAR-associating protein. Sumoylation-deficient SATB1 (SATB1(K744R)) failed to display the characteristic caspase cleavage pattern; however, fusion of SUMO in-frame to SATB1(K744R) restored cleavage. A SUMO-independent interaction of inactive caspase-6 and SATB1 was noted. A subset of total cellular SATB1 localized into promyelocytic leukemia nuclear bodies where enhanced SATB1 cleavage was detected subsequent to caspase activation. These results reveal a novel sumoylation-directed caspase cleavage of this key regulatory molecule. The role of regulated proteolysis of SATB1 may be to control transcription in immune cells during normal cell functions or to assist in efficient and rapid clearance of nonfunctional or potentially damaging immune cells.
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Is SATB1 positioned close to AT-rich sequences?
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SATB1 (special AT-rich sequence-binding protein-1) provides a key link between DNA loop organization, chromatin modification/remodeling, and association of transcription factors at matrix attachment regions (MARs).
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Primary brain tumors constitute a substantial public health problem with 66,290 cases diagnosed in the US in 2012, and 13,700 deaths recorded. With discovery of genetic factors associated with specific brain tumor subtypes, the goal of therapy is changing from treating a class of tumors to developing individualized therapies catering to the molecular composition of the actual tumor. For oligodendrogliomas, the loss of 1p/19q due to an unbalanced translocation improves both survival and the response to therapy, and is thus both a prognostic and a predictive marker. Several additional genetic alterations such as EGFR amplification, MGMT methylation, PDGFR activation, and 9p and 10q loss, have improved our understanding of the characteristics of these tumors and may help guide therapy in the future. For astrocytic tumors, MGMT is associated with a better prognosis and an improved response to temozolomide, and for all glial tumors, mutations in the IDH1 gene are possibly the most potent of good prognostic markers. Three of these markers - 1p/19q deletions, MGMT methylation status, and mutations in the IDH1 gene - are so potent that a new brain tumor subtype, the "triple negative" glioma (1p/19q intact, MGMT unmethylated, IDH1 non-mutated) has entered common parlance. Newer markers, such as CD 133, require additional investigation to determine their prognostic and predictive utility. In medulloblastomas, markers of WNT activation, MYCC/MCYN amplification, and TrkC expression levels are reliable prognostic indicators, but do not yet drive specific treatment selection. Many other proposed markers, such as 17q gain, TP53 mutations, and hMOF protein expression show promise, but are not yet ready for prime time. In this chapter, we focus on the markers that have shown convincing prognostic, predictive, and diagnostic value, and discuss potential markers that are being currently being intensively investigated. We also discuss serum profiling of tumors in an effort to discover additional potential markers.
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How are triple negative gliomas characterized?
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Three of these markers - 1p/19q deletions, MGMT methylation status, and mutations in the IDH1 gene - are so potent that a new brain tumor subtype, the "triple negative" glioma (1p/19q intact, MGMT unmethylated, IDH1 non-mutated) has entered common parlance.
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Protein-protein interactions (PPIs) control all functions and physiological states of the cell. Identification and understanding of novel PPIs would facilitate the discovery of new biological models and therapeutic targets for clinical intervention. Numerous resources and PPI databases have been developed to define a global interactome through the PPI data mining, curation, and integration of different types of experimental evidence obtained with various methods in different model systems. On the other hand, the recent advances in cancer genomics and proteomics have revealed a critical role of genomic alterations in acquisition of cancer hallmarks through a dysregulated network of oncogenic PPIs. Deciphering of cancer-specific interactome would uncover new mechanisms of oncogenic signaling for therapeutic interrogation. Toward this goal our team has developed a high-throughput screening platform to detect PPIs between cancer-associated proteins in the context of cancer cells. The established network of oncogenic PPIs, termed the OncoPPi network, is available through the OncoPPi Portal, an interactive web resource that allows to access and interpret a high-quality cancer-focused network of PPIs experimentally detected in cancer cell lines integrated with the analysis of mutual exclusivity of genomic alterations, cellular co-localization of interacting proteins, domain-domain interactions, and therapeutic connectivity. This chapter presents a guide to explore the OncoPPi network using the OncoPPi Portal to facilitate cancer biology.
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Which portal has been developed to explore protein-protein interactions in cancer cell lines?
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This chapter presents a guide to explore the OncoPPi network using the OncoPPi Portal to facilitate cancer biology.
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The transcription factor Zelda plays a pivotal role in promoting the maternal to zygotic transition during embryogenesis in Drosophila melanogaster. However, little is known about its role later in development. Here we are showing that Zelda is essential for proper wing development through gain and loss of function experiments. Zelda's transcript variants RB, RC and RD are present in imaginal wing discs of third instar larvae and the production of 2 protein isoforms of ∼180 and ∼70kD was detected in the same tissue. In ChIP experiments using larval wing discs, Zelda was found to bind to a region of the optomotor-blind gene, suggesting an interaction with a Dpp target that promotes wing growth and patterning.
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What is the function of the zelda transcription factor in D. melanogaster?
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The transcription factor Zelda plays a pivotal role in promoting the maternal to zygotic transition during embryogenesis in Drosophila melanogaster.
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The isolated working heart preparation was used to investigate the effect of continuous triiodothyronine (T3) administration on cardiac function and metabolism of rats rendered diabetic for a period of 4 wk with streptozocin (STZ). T3 controlled-release pellets were implanted 1 wk after STZ (70 mg/kg) injection. Rats injected with citrate buffer without STZ received T3 pellets 1 and/or 2 wk later. A comparable number of rats received placebo pellets. Untreated diabetic rats exhibited a decrease in spontaneous heart rate and myocardial cytochrome c concentrations concurrent with depressed plasma T3 values compared with untreated controls. T3 treatment did not improve in vitro cardiac performance (assessed as cardiac output times peak systolic pressure per gram dry heart weight) in hearts from diabetic rats perfused with glucose alone. Addition of octanoate reversed this depression and improved cardiac function to a greater extent in treated than in untreated diabetic animals. However, these differences between treated and untreated diabetic animals disappeared when heart rate was controlled by cardiac pacing. Furthermore, T3 treatment of controls and diabetics did not alter the oxidation of octanoate or the cardiac responsiveness to isoproterenol. These results suggest that experimental diabetic cardiomyopathy is partly attributable to a substrate deficiency and is not due entirely to hypothyroidism.
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How are thyroid hormones involved in the development of diabetic cardiomyopathy?
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T3 treatment did not improve in vitro cardiac performance (assessed as cardiac output times peak systolic pressure per gram dry heart weight) in hearts from diabetic rats perfused with glucose alone.
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In humans, the geographical apportionment of the coding diversity of the pigmentary locus melanocortin-1 receptor (MC1R) is, unusually, higher in Eurasians than in Africans. This atypical observation has been interpreted as the result of purifying selection due to functional constraint on MC1R in high UV-B radiation environments. By analyzing 3,142 human MC1R alleles from different regions of Spain in the context of additional haplotypic information from the 1000 Genomes (1000G) Project data, we show that purifying selection is also strong in southern Europe, but not so in northern Europe. Furthermore, we show that purifying and positive selection act simultaneously on MC1R. Thus, at least in Spain, regions at opposite ends of the incident UV-B radiation distribution show significantly different frequencies for the melanoma-risk allele V60L (a mutation also associated to red hair and fair skin and even blonde hair), with higher frequency of V60L at those regions of lower incident UV-B radiation. Besides, using the 1000G south European data, we show that the V60L haplogroup is also characterized by an extended haplotype homozygosity (EHH) pattern indicative of positive selection. We, thus, provide evidence for an adaptive value of human skin depigmentation in Europe and illustrate how an adaptive process can simultaneously help to maintain a disease-risk allele. In addition, our data support the hypothesis proposed by Jablonski and Chaplin (Human skin pigmentation as an adaptation to UVB radiation. Proc Natl Acad Sci U S A. 2010;107:8962-8968), which posits that habitation of middle latitudes involved the evolution of partially depigmented phenotypes that are still capable of suitable tanning.
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What phenotype is associated with the V60L mutation in the human MC1R gene?
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Thus, at least in Spain, regions at opposite ends of the incident UV-B radiation distribution show significantly different frequencies for the melanoma-risk allele V60L (a mutation also associated to red hair and fair skin and even blonde hair), with higher frequency of V60L at those regions of lower incident UV-B radiation.
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The conventional approach to vaccine development requires cultivation of the pathogenic microorganism and its dissection using biochemical, immunological, and microbiological methods in order to identify the components important for immunity. This method, while successful in many cases, failed to provide a solution for many of those pathogens for which a vaccine is not yet available. Today, the possibility of using genomic information allows us to study vaccine development in silico, without the need of cultivating the pathogen. This approach, which we have named 'reverse vaccinology', reduces the time required for the identification of candidate vaccines and provides new solutions for those vaccines which have been difficult or impossible to develop. The potential of this new approach is illustrated by the use of reverse vaccinology for the development of a vaccine against serogroup B meningococcus. The application of reverse vaccinology to other fields, including viral vaccines is discussed.
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Against which organisms has reverse vaccinology been used?
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The potential of this new approach is illustrated by the use of reverse vaccinology for the development of a vaccine against serogroup B meningococcus
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The epigenetic mechanisms in regulation of genes' expression seem to be another field of research that gains land in genetic association studies of rheumatoid arthritis (RA) susceptibility factors. Recently, a new class of molecules has been discovered, the microRNAs (miRNAs). miRNAs are related to post-transcriptional regulation of genes' expression. Different expression patterns of mir-146a, miRNA-155, miRNA-124a, mir-203, mir-223, mir-346, mir-132, mir-363, mir-498, mir-15a, and mir-16 were documented in several tissue sample types of RA patients. The polymorphisms of these miRNAs and their gene targets, which previously have been associated with RA or other autoimmune diseases, are also reviewed. Finally, using web-based tools we propose polymorphisms of the discussed miRNAs and their gene-targets that worth to be studied for their role in RA predisposition.
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Which micro-RNAs have been associated in the pathogenesis of Rheumatoid Arthritis?
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Different expression patterns of mir-146a, miRNA-155, miRNA-124a, mir-203, mir-223, mir-346, mir-132, mir-363, mir-498, mir-15a, and mir-16 were documented in several tissue sample types of RA patients
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The major heat shock protein, chaperonin 60, has been established to have intercellular signaling activity in addition to its established protein-folding function. Mycobacterium tuberculosis is one of a small proportion of bacteria to encode two chaperonin 60 proteins. We have demonstrated that chaperonin 60.1 from this bacterium is a very active stimulator of human monocytes. To determine structure/function relationships of chaperonin 60.1 we have cloned and expressed the apical, equatorial, and intermediate domains of this protein. We have found that the signaling activity of M. tuberculosis chaperonin 60.1 resides in the equatorial domain. This activity of the recombinant equatorial domain was completely blocked by treating the protein with proteinase K, ruling out lipopolysaccharide contamination as the cause of the cell activation. Blockade of the activity of the equatorial domain by anti-CD14 monoclonal antibodies reveals that this domain activates monocytes by binding to CD14. Looking at the oligomeric state of the active proteins, using native gel electrophoresis and protein cross-linking we found that recombinant M. tuberculosis chaperonin 60.1 fails to form the prototypic tetradecameric structure of chaperonin 60 proteins under the conditions tested and only forms dimers. It is therefore concluded that the monocyte-stimulating activity of M. tuberculosis Cpn60.1 resides in the monomeric subunit and within this subunit the biological activity is due to the equatorial domain.
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What is the function of a chaperonin?
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The major heat shock protein, chaperonin 60, has been established to have intercellular signaling activity in addition to its established protein-folding function.
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On August 30, 2017, the U.S. Food and Drug Administration (FDA) approved Novartis' tisagenlecleucel (CTL-019, Kymriah), which is a synthetic bioimmune product of anti-CD19 chimeric antigen receptor (CAR) T cells, for the treatment of relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). This was a milestone in tumor immunology on account of the significant antitumor effect of tisagenlecleucel for the treatment of relapsed/refractory B-ALL patients. Conventional standard therapies for B-ALL have high failure rates, thus developing new therapies is crucial for patients with B-ALL. Results from clinical trials indicate that anti-CD19 CAR T-cell therapies could successfully induce high response rates in B-ALL patients. However, related toxicities, such as cytokine release syndrome and CAR T-cell-related encephalopathy syndrome, may be severe or even fatal, and the management of such toxicities is therefore vital. This review will focus on the clinical application of anti-CD19 CAR T-cell therapy in B-ALL treatment, including design features of CAR constructs, therapeutic use of tisagenlecleucel, CAR T-cell therapy clinical trials and related toxicity, and prospects for cancer immunotherapy.
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Is Tisagenlecleucel effective for B-Cell Lymphoma?
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This was a milestone in tumor immunology on account of the significant antitumor effect of tisagenlecleucel for the treatment of relapsed/refractory B-ALL patients.
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Non-small-cell lung cancer patients with activating mutations in epidermal growth factor receptor (EGFR) respond to EGFR tyrosine kinase inhibitor (TKI) treatment. Nevertheless, patients often develop central nervous system (CNS) metastases during treatment, even when their extracranial tumors are still under control. In the absence of effective options, much higher doses of EGFR TKIs have been attempted clinically, with the goal of achieving high enough drug concentrations within the CNS. Although limited tumor responses have been observed with this approach, the toxicities outside the CNS have been too high to tolerate. We report the discovery and early clinical development of AZD3759, a selective EGFR inhibitor that can fully penetrate the blood-brain barrier (BBB), with equal free concentrations in the blood, cerebrospinal fluid, and brain tissue. Treatment with AZD3759 causes tumor regression in subcutaneous xenograft, leptomeningeal metastasis (LM), and brain metastasis (BM) lung cancer models and prevents the development of BM in nude mice. An early clinical study in patients with BM and LM treated with AZD3759 confirms its BBB-penetrant properties and antitumor activities. Our data demonstrate the potential of AZD3759 for the treatment of BM and LM and support its further clinical evaluation in larger trials.
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Does AZD3759 cross the blood brain barrier?
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We report the discovery and early clinical development of AZD3759, a selective EGFR inhibitor that can fully penetrate the blood-brain barrier (BBB),
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Genomic enhancers are important regulators of gene expression, but their identification is a challenge, and methods depend on indirect measures of activity. We developed a method termed STARR-seq to directly and quantitatively assess enhancer activity for millions of candidates from arbitrary sources of DNA, which enables screens across entire genomes. When applied to the Drosophila genome, STARR-seq identifies thousands of cell type-specific enhancers across a broad continuum of strengths, links differential gene expression to differences in enhancer activity, and creates a genome-wide quantitative enhancer map. This map reveals the highly complex regulation of transcription, with several independent enhancers for both developmental regulators and ubiquitously expressed genes. STARR-seq can be used to identify and quantify enhancer activity in other eukaryotes, including humans.
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What is STARR-seq?
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We developed a method termed STARR-seq to directly and quantitatively assess enhancer activity for millions of candidates from arbitrary sources of DNA, which enables screens across entire genomes.
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Fanconi anemia is an inherited disease characterized by bone marrow failure, congenital malformations, and predisposition to cancer. The breast cancer susceptibility gene BRCA2 was recently found to be associated with Fanconi anemia complementation group D1 (FA-D1). We examined four kindreds afflicted with Fanconi anemia for the presence of germline BRCA2 mutations. One kindred, of Ashkenazi Jewish ancestry, had five members who were diagnosed with breast cancer and two cousins who were BRCA2*6174delT/C3069X compound heterozygotes and had Fanconi anemia and brain tumors. In another kindred of Ashkenazi Jewish and Lithuanian Catholic ancestry, a child with Fanconi anemia and a medulloblastoma was a BRCA2*6174delT/886delGT compound heterozygote. Two other kindreds each contained a Fanconi anemia-afflicted child who developed medulloblastoma; one child was of Latin American ancestry and a compound heterozygote for BRCA2*I2490T/ 5301insA and the other was African American and a compound heterozygote for BRCA2*Q3066X/E1308X. Median age of the Fanconi anemia-afflicted children at brain tumor diagnosis was 3.5 years. The co-occurrence of brain tumors, Fanconi anemia, and breast cancer observed in one of these kindreds constitutes a new syndromic association. Individuals who carry a germline BRCA2 mutation and who plan to have children with a partner of Ashkenazi Jewish descent should consider undergoing genetic counseling.
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Which is the genetic cause for the development of Fanconi anemia complementation group D1?
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Two other kindreds each contained a Fanconi anemia-afflicted child who developed medulloblastoma; one child was of Latin American ancestry and a compound heterozygote for BRCA2*I2490T/ 5301insA and the other was African American and a compound heterozygote for BRCA2*Q3066X/E1308X
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Thyroid-associated ophthalmopathy (TAO) is an autoimmune component of Graves' disease for which no currently available medical therapy provides reliable and safe benefit. Based on insights generated experimentally over the past several decades, the insulin-like growth factor-I receptor (IGF-IR) has been implicated in the pathogenesis of TAO. Furthermore, an IGF-IR inhibitor, teprotumumab, has emerged from 2 clinical trials as a promising treatment for active, moderate to severe TAO. This brief review intends to provide an overview of the rationale underlying the development of teprotumumab for this disease. It is possible that teprotumumab will soon take its place in our therapeutic armamentarium for active TAO.
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Which molecule is targeted by Teprotumumab?
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Furthermore, an IGF-IR inhibitor, teprotumumab, has emerged from 2 clinical trials as a promising treatment for active, moderate to severe TAO.
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Internal tandem duplications (ITD) mutation within FMS-like tyrosine kinase 3 (FLT3), the most frequent mutation happens in almost 20% acute myeloid leukemia (AML) patients, always predicts a poor prognosis. As a small molecule tyrosine kinase inhibitor, sorafenib is clinically used for the treatment of advanced renal cell carcinoma (RCC), hepatocellular carcinoma (HCC), and differentiated thyroid cancer (DTC), with its preclinical and clinical activity demonstrated in the treatment of Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutant AML. Even though it shows a rosy future in the AML treatment, the short response duration remains a vital problem that leads to treatment failure. Rapid onset of drug resistance is still a thorny problem that we cannot overlook. Although the mechanisms of drug resistance have been studied extensively in the past years, there is still no consensus on the exact reason for resistance and without effective therapeutic regimens established clinically. My previous work reported that sorafenib-resistant FLT3-ITD mutant AML cells displayed mitochondria dysfunction, which rendered cells depending on glycolysis for energy supply. In my present one, we further illustrated that losing the target protein FLT3 and the continuously activated PI3K/Akt signaling pathway may be the reason for drug resistance, with sustained activation of PI3K/AKT signaling responsible for the highly glycolytic activity and adenosine triphosphate (ATP) generation. PI3K inhibitor, LY294002, can block PI3K/AKT signaling, further inhibit glycolysis to disturb ATP production, and finally induce cell apoptosis. This finding would pave the way to remedy the FLT3-ITD mutant AML patients who failed with FLT3 targeted therapy.
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Which signaling pathway does LY294002 inhibit?
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PI3K inhibitor, LY294002, can block PI3K/AKT signaling, further inhibit glycolysis to disturb ATP production, and finally induce cell apoptosis.
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Nucleosome dynamics facilitated by histone turnover is required for transcription as well as DNA replication and repair. Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me). In order to correlate histone modifications and transcription-dependent histone turnover, we performed genome wide analyses for euchromatic regions in G2/M-arrested fission yeast. The results show that transcription-dependent histone turnover at 5' promoter and 3' termination regions is directly correlated with the occurrence of H3K56Ac and H4K20 mono-methylation (H4K20me1) in actively transcribed genes. Furthermore, the increase of H3K56Ac and H4K20me1 and antisense RNA production was observed in the absence of the histone H3K36 methyltransferase Set2 and histone deacetylase complex (HDAC) that are involved in the suppression of histone turnover within the coding regions. These results together indicate that H4K20me1 as well as H3K56Ac are bona fide marks for transcription-dependent histone turnover in fission yeast.
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Is H4K20 methylation associated with DNA replication?
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Histone turnover is often associated with various histone modifications such as H3K56 acetylation (H3K56Ac), H3K36 methylation (H3K36me), and H4K20 methylation (H4K20me).
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A major component of bacterial biofilms is curli amyloid fibrils secreted by the curli biogenesis system. Understanding the curli biogenesis mechanism is critical for developing therapeutic agents for biofilm-related infections. Here we report a systematic study of the curli biogenesis system, highlighted by structural, biochemical and functional analysis of the secretion channel complexes (CsgF-CsgG) with and without the curli substrate. The dual-pore architecture of the CsgF-CsgG complex was observed and used to develop an approach to inhibit the curli secretion by physically reducing the size of the CsgF pore. We further elucidated the assembly of the CsgFG complex with curli components (CsgA and CsgB) and curli-cell association through CsgF. Importantly, the recognition of the CsgA substrate by CsgG was uncovered. Nine crevices outside of the CsgG channel provide specific and highly-conserved recognition sites for CsgA N-terminus. Together with analysis of CsgE, our study provides comprehensive insights into curli biogenesis.
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What is known about the protein Curli?
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A major component of bacterial biofilms is curli amyloid fibrils secreted by the curli biogenesis system.
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The identification of genetic variants affecting gene expression, namely expression quantitative trait loci (eQTLs), has contributed to the understanding of mechanisms underlying human traits and diseases. The majority of these variants map in non-coding regulatory regions of the genome and their identification remains challenging. Here, we use natural genetic variation and CAGE transcriptomes from 154 EBV-transformed lymphoblastoid cell lines, derived from unrelated individuals, to map 5376 and 110 regulatory variants associated with promoter usage (puQTLs) and enhancer activity (eaQTLs), respectively. We characterize five categories of genes associated with puQTLs, distinguishing single from multi-promoter genes. Among multi-promoter genes, we find puQTL effects either specific to a single promoter or to multiple promoters with variable effect orientations. Regulatory variants associated with opposite effects on different mRNA isoforms suggest compensatory mechanisms occurring between alternative promoters. Our analyses identify differential promoter usage and modulation of enhancer activity as molecular mechanisms underlying eQTLs related to regulatory elements.
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What are the puQTLs (promoter-usage Quantitative Trait Loci)?
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Here, we use natural genetic variation and CAGE transcriptomes from 154 EBV-transformed lymphoblastoid cell lines, derived from unrelated individuals, to map 5376 and 110 regulatory variants associated with promoter usage (puQTLs) and enhancer activity (eaQTLs), respectively.
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Pre-clinical and clinical data suggest that the development of a safe and effective anti-amyloid-beta (Abeta) immunotherapy for Alzheimer's disease (AD) will require therapeutic levels of anti-Abeta antibodies, while avoiding proinflammatory adjuvants and autoreactive T cells which may increase the incidence of adverse events in the elderly population targeted to receive immunotherapy. The first active immunization clinical trial with AN1792 in AD patients was halted when a subset of patients developed meningoencephalitis. The first passive immunotherapy trial with bapineuzumab, a humanized monoclonal antibody against the end terminus of Abeta, also encountered some dose dependent adverse events during the Phase II portion of the study, vasogenic edema in 12 cases, which were significantly over represented in ApoE4 carriers. The proposed remedy is to treat future patients with lower doses, particularly in the ApoE4 carriers. Currently there are at least five ongoing anti-Abeta immunotherapy clinical trials. Three of the clinical trials use humanized monoclonal antibodies, which are expensive and require repeated dosing to maintain therapeutic levels of the antibodies in the patient. However in the event of an adverse response to the passive therapy antibody delivery can simply be halted, which may provide a resolution to the problem. Because at this point we cannot readily identify individuals in the preclinical or prodromal stages of AD pathogenesis, passive immunotherapy is reserved for those that already have clinical symptoms. Unfortunately those individuals have by that point accumulated substantial neuropathology in affected regions of the brain. Moreover, if Abeta pathology drives tau pathology as reported in several transgenic animal models, and once established if tau pathology can become self propagating, then early intervention with anti-Abeta immunotherapy may be critical for favorable clinical outcomes. On the other hand, active immunization has several significant advantages, including lower cost and the typical immunization protocol should be much less intrusive to the patient relative to passive therapy, in the advent of Abeta-antibody immune complex-induced adverse events the patients will have to receive immuno-supperssive therapy for an extended period until the anti Abeta antibody levels drop naturally as the effects of the vaccine decays over time. Obviously, improvements in vaccine design are needed to improve both the safety, as well as the efficacy of anti-Abeta immunotherapy. The focus of this review is on the advantages of DNA vaccination for anti-Abeta immunotherapy, and the major hurdles, such as immunosenescence, selection of appropriate molecular adjuvants, universal T cell epitopes, and possibly a polyepitope design based on utilizing existing memory T cells in the general population that were generated in response to childhood or seasonal vaccines, as well as various infections. Ultimately, we believe that the further refinement of our AD DNA epitope vaccines, possibly combined with a prime boost regime will facilitate translation to human clinical trials in either very early AD, or preferably in preclinical stage individuals identified by validated AD biomarkers.
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Is bapineuzumab effective for treatment of patients with Alzheimer's disease?
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The first passive immunotherapy trial with bapineuzumab, a humanized monoclonal antibody against the end terminus of Abeta, also encountered some dose dependent adverse events during the Phase II portion of the study, vasogenic edema in 12 cases, which were significantly over represented in ApoE4 carriers.
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Although the facioscapulohumeral muscular dystrophy (FSHD) locus was mapped to 4q35 chromosomal region in 1990, no gene transcript has been as yet identified. Molecular diagnosis is based mainly on the detection of deletions of a 3.3 kb-tandem repeat array in the locus. This procedure offers almost 95% accuracy but is quite complicated and therefore a simpler test would be preferable. We describe a convenient non-radioactive protocol which requires a simple PCR probe synthesis and labelling procedure, thus facilitating and accelerating the standard Southern blot based DNA test. 134 individuals (113 affected and 21 unaffected relatives) were studied and a causal deletion was detected in 72.
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Which diagnostic tests are used for the diagnosis of FSHD?
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Molecular diagnosis is based mainly on the detection of deletions of a 3.3 kb-tandem repeat array in the locus.
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The eukaryotic replisome is a crucial determinant of genome stability, but its structure is still poorly understood. We found previously that many regulatory proteins assemble around the MCM2-7 helicase at yeast replication forks to form the replisome progression complex (RPC), which might link MCM2-7 to other replisome components. Here, we show that the RPC associates with DNA polymerase alpha that primes each Okazaki fragment during lagging strand synthesis. Our data indicate that a complex of the GINS and Ctf4 components of the RPC is crucial to couple MCM2-7 to DNA polymerase alpha. Others have found recently that the Mrc1 subunit of RPCs binds DNA polymerase epsilon, which synthesises the leading strand at DNA replication forks. We show that cells lacking both Ctf4 and Mrc1 experience chronic activation of the DNA damage checkpoint during chromosome replication and do not complete the cell cycle. These findings indicate that coupling MCM2-7 to replicative polymerases is an important feature of the regulation of chromosome replication in eukaryotes, and highlight a key role for Ctf4 in this process.
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List the components of a Replisome Progression Complex (RPC).
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We found previously that many regulatory proteins assemble around the MCM2-7 helicase at yeast replication forks to form the replisome progression complex (RPC), which might link MCM2-7 to other replisome components.
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The production of cytokines in response to DNA-damage events may be an important host defense response to help prevent the escape of pre-cancerous cells. The innate immune pathways involved in these events are known to be regulated by cellular molecules such as stimulator of interferon genes (STING), which controls type I interferon and pro-inflammatory cytokine production in response to the presence of microbial DNA or cytosolic DNA that has escaped from the nucleus. STING signaling has been shown to be defective in a variety of cancers, such as colon cancer and melanoma, actions that may enable damaged cells to escape the immunosurveillance system. Here, we report through examination of databases that STING signaling may be commonly suppressed in a greater variety of tumors due to loss-of-function mutation or epigenetic silencing of the STING/cGAS promoter regions. In comparison, RNA activated innate immune pathways controlled by RIG-I/MDA5 were significantly less affected. Examination of reported missense STING variants confirmed that many exhibited a loss-of-function phenotype and could not activate cytokine production following exposure to cytosolic DNA or DNA-damage events. Our data imply that the STING signaling pathway may be recurrently suppressed by a number of mechanisms in a considerable variety of malignant disease and be a requirement for cellular transformation.
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What is the function of the protein encoded by the gene STING?
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The production of cytokines in response to DNA-damage events may be an important host defense response to help prevent the escape of pre-cancerous cells. The innate immune pathways involved in these events are known to be regulated by cellular molecules such as stimulator of interferon genes (STING), which controls type I interferon and pro-inflammatory cytokine production in response to the presence of microbial DNA or cytosolic DNA that has escaped from the nucleus.
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Recent reports have described a secondary Multisystem Inflammatory Syndrome in Children (MIS-C) after a prior COVID-19 infection that often has features of Kawasaki disease (KD). Here, we report the case of a 36-year-old woman who presented to the emergency department hypotensive and tachycardic after 1 week of fevers, abdominal pain, vomiting and diarrhea, and was found to have the classic phenotype of complete Kawasaki's Disease including nonexudative conjunctivitis, cracked lips, edema of the hands and feet, palmar erythema, a diffuse maculopapular rash, and cervical lymphadenopathy. Initial laboratory studies were significant for hyponatremia, elevated liver function tests including direct hyperbilirubinemia, and leukocytosis with neutrophilia. Imaging revealed mild gallbladder wall edema, a small area of colitis, and small pleural effusion. She was treated for Kawasaki Disease Shock Syndrome (KDSS) with pulse dose solumedrol, IVIG, and aspirin with near resolution of symptoms and normalization of vital signs within 1 day and subsequent improvement in her laboratory abnormalities. She was later found to be COVID-19 IgG positive, suggesting past exposure. This case represents an early report of a KD-like illness in an adult with serologic evidence of a previous COVID-19 infection, similar to MIS-C. It suggests that the virulent strain of SARS-CoV-2 appears to cause a post-infectious inflammatory syndrome similar to KD in adults, as well as children. Our understanding of the myriad of COVID-19 symptoms and sequelae is rapidly evolving. We recommend physicians remain vigilant for inflammatory syndromes that mimic KD/KDSS which may warrant prompt treatment with IVIG and steroids.
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Is MIS-C or Multisystem Inflammatory syndrome in children a complication of Covid-19?
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Recent reports have described a secondary Multisystem Inflammatory Syndrome in Children (MIS-C) after a prior COVID-19 infection that often has features of Kawasaki disease (KD).
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Autosomal dominant osteogenesis imperfecta is caused by mutations in the COL1A2 and COL1A1 genes of type I collagen. In a family with OI type IV genetically linked to the COL1A2 gene, we attempted prenatal diagnosis in a pregnancy at risk by genotyping the DNA of the fetus for a COL1A2 gene associated RFLP. Our results showed that the fetus inherited the normal COL1A2 allele from her affected parent. Linkage analysis can thus be used in the prenatal diagnosis of dominantly inherited osteogenesis imperfecta.
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Is autosomal dominant inheritanced form of Osteogenesis imperfecta caused by mutations in the genes associated with collagen production?
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Autosomal dominant osteogenesis imperfecta is caused by mutations in the COL1A2 and COL1A1 genes of type I collagen.
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The melanocortin 1 receptor (MC1R) is involved in the control of melanogenesis. Polymorphisms in this gene have been associated with variation in skin and hair color and with elevated risk for the development of melanoma. Here we used 11 computational tools based on different approaches to predict the damage-associated non-synonymous single nucleotide polymorphisms (nsSNPs) in the coding region of the human MC1R gene. Among the 92 nsSNPs arranged according to the predictions 62% were classified as damaging in more than five tools. The classification was significantly correlated with the scores of two consensus programs. Alleles associated with the red hair color (RHC) phenotype and with the risk of melanoma were examined. The R variants D84E, R142H, R151C, I155T, R160W and D294H were classified as damaging by the majority of the tools while the r variants V60L, V92M and R163Q have been predicted as neutral in most of the programs The combination of the prediction tools results in 14 nsSNPs indicated as the most damaging mutations in MC1R (L48P, R67W, H70Y, P72L, S83P, R151H, S172I, L206P, T242I, G255R, P256S, C273Y, C289R and R306H); C273Y showed to be highly damaging in SIFT, Polyphen-2, MutPred, PANTHER and PROVEAN scores. The computational analysis proved capable of identifying the potentially damaging nsSNPs in MC1R, which are candidates for further laboratory studies of the functional and pharmacological significance of the alterations in the receptor and the phenotypic outcomes.
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What phenotype is associated with the V60L mutation in the human MC1R gene?
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The combination of the prediction tools results in 14 nsSNPs indicated as the most damaging mutations in MC1R (L48P, R67W, H70Y, P72L, S83P, R151H, S172I, L206P, T242I, G255R, P256S, C273Y, C289R and R306H); C273Y showed to be highly damaging in SIFT, Polyphen-2, MutPred, PANTHER and PROVEAN scores.
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Molecular regulation of p73, a p53 family member, remains unclear. Here we report that p73 expression is significantly regulated by cell densities. In particular, we found that p73alpha and p73beta are differentially regulated. While p73beta protein levels were inversely correlated with cell densities, p73alpha protein levels behaved oppositely. We further showed that density-dependent changes of p73alpha follow the same patterns as E2F-1 and TAp73 mRNA levels, suggesting transcriptional regulation. Our data also suggest that high levels of p73beta at lower densities may be due to increased protein stability. However, AIP-4/Itch appeared not to be involved in downregulation of p73beta at high densities. Moreover, we also found that subcellular location of p73 isoforms changes with the culture density increases. While high level of p73beta at low density was mainly presented in the nucleus, low levels of this protein at high densities were mainly in the cytosol. Taken together, these findings reveal a novel mechanism that differentially regulates p73 isoforms and underscores the role of cell-cell interaction in p73 regulation, which may advance our understanding of p73 expression and function in human cancers.
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How many TAp73 isoforms have been identified in humans?
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Moreover, we also found that subcellular location of p73 isoforms changes with the culture density increases.
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Glioblastoma (GBM) is the most common primary malignant brain tumor that nearly always results in a bad prognosis. Temozolomide plus radiotherapy (TEM+RAD) is the most common treatment for newly diagnosed GBM. With the development of molecularly targeted drugs, several clinical trials were reported; however, the efficacy of the treatment remains controversial. So we attempted to measure the dose of the molecularly targeted drug that could improve the prognosis of those patients. The appropriate electronic databases (PubMed, MEDLINE, EMBASE, and the Cochrane Library) were searched for relevant studies. A meta-analysis was performed after determining which studies met the inclusion criteria. Six randomized, controlled trials (RCTs) were identified for this meta-analysis, comprising 2,637 GBM patients. The benefit of overall survival (OS) was hazard ratio (HZ), 0.936 [95% confidence interval (CI), 0.852-1.028]. The benefit with respect to progression-free survival (PFS) rate was HZ of 0.796 (95% CI, 0.701-0.903). OS benefit of cilengitide was HZ of 0.792 (95% CI, 0.642-0.977). The adverse effects higher than grade 3 were 57.7% in the experimental group and 44.1% in the placebo group (odds ratio, 1.679; 95% CI, 1.434-1.967). The addition of molecularly targeted drugs to TEM + RAD did not improve the OS of patients with GBM; however, it did improve PFS in patients treated by cilengitide who could not get improvement in OS. The rate of adverse effects was higher in the experimental group than in the placebo group.
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Is cilengitide effective for treatment of glioblastoma?
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he addition of molecularly targeted drugs to TEM + RAD did not improve the OS of patients with GBM; however, it did improve PFS in patients treated by cilengitide who could not get improvement in OS.
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