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991.

Background

Dengue is the most prevalent mosquito borne infection worldwide. Vertical transmissions after maternal dengue infection to the fetus and pregnancy losses in relation to dengue illness have been reported. The relationship of dengue to miscarriage is not known.

Method

We aimed to establish the relationship of recent dengue infection and miscarriage. Women who presented with miscarriage (up to 22 weeks gestation) to our hospital were approached to participate in the study. For each case of miscarriage, we recruited 3 controls with viable pregnancies at a similar gestation. A brief questionnaire on recent febrile illness and prior dengue infection was answered. Blood was drawn from participants, processed and the frozen serum was stored. Stored sera were thawed and then tested in batches with dengue specific IgM capture ELISA, dengue non-structural protein 1 (NS1) antigen and dengue specific IgG ELISA tests. Controls remained in the analysis if their pregnancies continued beyond 22 weeks gestation. Tests were run on 116 case and 341 control sera. One case (a misdiagnosed viable early pregnancy) plus 45 controls (39 lost to follow up and six subsequent late miscarriages) were excluded from analysis.

Findings

Dengue specific IgM or dengue NS1 antigen (indicating recent dengue infection) was positive in 6/115 (5·2%) cases and 5/296 (1·7%) controls RR 3·1 (95% CI 1·0–10) P = 0·047. Maternal age, gestational age, parity and ethnicity were dissimilar between cases and controls. After adjustments for these factors, recent dengue infection remained significantly more frequently detected in cases than controls (AOR 4·2 95% CI 1·2–14 P = 0·023).

Interpretation

Recent dengue infections were more frequently detected in women presenting with miscarriage than in controls whose pregnancies were viable. After adjustments for confounders, the positive association remained.  相似文献   
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Purified rat liver plasma membranes were incubated for 0-60 min with [gamma-32P]ATP and analysis of 32P-labeled proteins by means of sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography revealed the presence of two shifted kinetic phenomena. The use of 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7), a potent inhibitor of protein kinases, allowed the identification of one as the endogenous protein phosphorylation. The other was shown to be the labeling of two phospho-intermediate forms of alkaline phosphatase (orthophosphoric monoester phosphohydrolase (alkaline optimum, EC 3.1.3.1.], which have apparent molecular masses of 151 and 135 kDa. Bromolevamisole, a potent inhibitor of the enzyme, stabilized these phospho-intermediates, and consequent on this inhibition the labelling of a 18 kDa phosphoprotein was augmented. So, when alkaline phosphatase was studied in its native plasma membrane environment, a specificity of this enzyme over the endogenous phosphoproteins was established.  相似文献   
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Species of the genus Himalopsyche (Trichoptera, Rhyacophilidae) inhabit alpine to montane environments in Central and East Asia and North America. Diversity of the genus is concentrated primarily in the Himalayas and surrounding mountain ranges. Phylogenetic hypotheses have hitherto been proposed based on morphological data. Here, we present the first molecular phylogeny of Himalopsyche based on six gene fragments, using three methods of phylogenetic inference. Based on the phylogenetic analyses, we re‐evaluated species groups suggested by previous authors based on adult male morphology. We found that the previously defined groups are largely supported by molecular evidence as well as larval and adult morphology. However, we modify the species groups so that Himalopsyche phryganea and Himalopsyche lepcha constitute monotypic groups, and so that the tibetana group and anomala group sensu Schmid & Botosaneanu are merged to a single group, here defined as the tibetana group. Thus, we propose that Himalopsyche can be divided into five groups: kuldschensis group, lepcha group, navasi group, phryganea group, and tibetana group. We also provide a biogeographic synthesis of Himalopsyche distributions.  相似文献   
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Biliary tract cancers (BTC) are aggressive tumours with a low survival rate. At the advent of the genomic era, various genetic mutations in cell signalling pathways have been incriminated in carcinogenesis. Genomic analysis studies have connected main components of the phosphoinositide-3-kinase (PI3K) signalling pathway to BTC. PI3K pathway playing a central role in cell signalling and being deregulated in various tumours has been studied as a target for chemotherapy. Novel compounds have also been identified in preclinical trials that specifically target the PI3K pathway in BTCs, but these studies have not accelerated to clinical use. These novel compounds can be examined in upcoming studies to validate them as potential therapeutic agents, as further research is required to combat the growing need for adjuvant chemotherapy to successfully battle this tumour type. Furthermore, these molecules could also be used along with gemcitabine, cisplatin and 5-fluorouracil to improve sensitivity of the tumour tissue to chemotherapy. This review focuses on the basics of PI3K signalling, genetic alterations of this pathway in BTCs and current advancement in targeting this pathway in BTCs. It emphasizes the need for gene-based drug screening in BTC. It may reveal various novel targets and drugs for amelioration of survival in patients with BTC and serve as a stepping stone for further research.  相似文献   
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The evolutionary events in organisms can be tracked to the transfer of genetic material. The inheritance of genetic material among closely related organisms is a slow evolutionary process. On the other hand, the movement of genes among distantly related species can account for rapid evolution. The later process has been quite evident in the appearance of antibiotic resistance genes among human and animal pathogens. Phylogenetic trees based on such genes and those involved in metabolic activities reflect the incongruencies in comparison to the 16S rDNA gene, generally used for taxonomic relationships. Such discrepancies in gene inheritance have been termed as horizontal gene transfer (HGT) events. In the post-genomic era, the explosion of known sequences through large-scale sequencing projects has unraveled the weakness of traditional 16S rDNA gene tree based evolutionary model. Various methods to scrutinize HGT events include atypical composition, abnormal sequence similarity, anomalous phylogenetic distribution, unusual phyletic patterns, etc. Since HGT generates greater genetic diversity, it is likely to increase resource use and ecosystem resilience.  相似文献   
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