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Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse, with 17 confirmed subtypes, and comprises approximately 13% of infections worldwide. In this study, we identified GT4 subtypes by phylogenetic analysis, assessed differences in patient demographics across GT4 subtypes, examined baseline sequence variability among subtypes and the potential impact on treatment outcome, and analyzed the development of viral resistance in patients who received a regimen of ombitasvir (nonstructural protein 5A [NS5A] inhibitor) plus ritonavir-boosted paritaprevir (NS3/4A inhibitor) with or without ribavirin (RBV) for the treatment of HCV GT4 infection. Phylogenetic analysis of HCV NS3/4A, NS5A, and NS5B nucleotide sequences identified 7 subtypes (4a, 4b, 4c, 4d, 4f, 4g/4k, and 4o) among 132 patient samples. Subtype prevalence varied by country, and the distributions of patient birth cohort and race were significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. Baseline amino acid variability was detected in NS5A across GT4 subtypes but had no impact on treatment outcome. Three patients experienced virologic failure and were infected with subtype 4d, and the predominant resistance-associated variants at the time of failure were D168V in NS3 and L28V in NS5A. Overall, high response rates were observed among patients infected with 7 HCV GT4 subtypes, with no impact of baseline variants on treatment outcome. GT4 subtype distribution in this study differed based on patient demographics and geography.  相似文献   
63.
Hexavalent chromium compounds are most commonly used in printing, dyeing, plastics and rayon manufacturing. Poisoning in children by ammonium dichromate, an odorless and bright orange-red crystal, are rarely reported. Acute poisoning will result in death due to multi-organ failure. The target organs that are affected by this poison are the respiratory system, kidneys, liver, eyes and skin. On ingestion, initially there is a relative lack of severe symptoms and signs. Hence, the delay in seeking medical attention could lead to the increased rate of mortality. In this case study, we report the ingestion of ammonium dichromate by a child. Despite appropriate management, such as hepatic supportive measures and plasma transfusion, the toxicity progressed to multi-organ failure and death.  相似文献   
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Poor growth is an under-recognised yet significant long-term sequelae of oesophageal atresia(OA) repair. Few studies have specifically explored the reasons for growth impairment in this complex cohort. The association between poor growth with younger age and fundoplication appears to have the strongest supportive evidence, highlighting the need for early involvement of a dietitian and speech pathologist, and consideration of optimal medical reflux management prior to referring for anti-reflux surgery. However, it remains difficult to reach conclusions regarding other factors which may negatively influence growth, due to conflicting findings, inconsistent definitions and lack of validated tool utilisation. While swallowing and feeding difficulties are particularly frequent in younger children, their relationship with growth remains unclear. It is possible that these morbidities impact on the diet of children with OA, but detailed analysis of dietary composition and quality, and its relationship with these complications and growth, has not yet been conducted. Another potential area of research in OA is the role of the microbiota in growth and nutrition. While the microbiota has been linked to growth impairment in other paediatric conditions,it is yet to be investigated in OA. Further research is needed to identify the most,important contributory factors to poor growth, the role of the intestinal microbiota, and effective interventions to maximise growth and nutritional outcomes in this cohort.  相似文献   
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Hammock valve, also known as anomalous mitral arcade is a rare mechanism for congenital mitral insufficiency. We report a case of a two-week-old neonate who presented with features of heart failure and an apical systolic murmur. Echocardiogram showed severe mitral regurgitation and abnormal mitral valve with direct attachment of mitral leaflets to papillary muscle without intervening chordae tendinae, typical of hammock valve. Heart failure was controlled with ionotrpes and diuretics. The literature on the hammock mitral valve is reviewed.  相似文献   
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Some amyloid-forming polypeptides are associated with devastating human diseases and others provide important biological functions. For both, oligomeric intermediates appear during amyloid assembly. Currently we have few tools for characterizing these conformationally labile intermediates and discerning what governs their benign versus toxic states. Here, we examine intermediates in the assembly of a normal, functional amyloid, the prion-determining region of yeast Sup35 (NM). During assembly, NM formed a variety of oligomers with different sizes and conformation-specific antibody reactivities. Earlier oligomers were less compact and reacted with the conformational antibody A11. More mature oligomers were more compact and reacted with conformational antibody OC. We found we could arrest NM in either of these two distinct oligomeric states with small molecules or crosslinking. The A11-reactive oligomers were more hydrophobic (as measured by Nile Red binding) and were highly toxic to neuronal cells, while OC-reactive oligomers were less hydrophobic and were not toxic. The A11 and OC antibodies were originally raised against oligomers of Aβ, an amyloidogenic peptide implicated in Alzheimer's disease (AD) that is completely unrelated to NM in sequence. Thus, this natural yeast prion samples two conformational states similar to those sampled by Aβ, and when assembly stalls at one of these two states, but not the other, it becomes extremely toxic. Our results have implications for selective pressures operating on the evolution of amyloid folds across a billion years of evolution. Understanding the features that govern such conformational transitions will shed light on human disease and evolution alike.  相似文献   
69.
Heart failure (HF) has steadily increased in prevalence and affects both males and females equally. Despite this, there has been a significant underrepresentation of women in large scale HF trials. This disparity has lead to a deficit in understanding important gender-based differences in pathophysiology, diagnosis and treatment strategies. We review these gaps and explore a biological basis for varying outcomes. Endogenous estrogen plays an important role in epidemiology and outcome. The administration of exogenous estrogen has had varied success in treatment and is outlined extensively below. Additionally, we highlight unique HF syndromes through pregnancy and important sex-specific issues concerning transplant and mechanical circulatory support. A central theme remains: there is a clear need for increased female recruitment in clinical trials, and more studies exploring the role of gender-based biology in HF treatment.  相似文献   
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