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PurposeHepatitis E virus (HEV) is responsible for >50% of acute viral hepatitis (AVH) in developing countries. It has 4 major genotypes and various subtypes which vary in geographical distribution, clinical manifestations and epidemiological patterns. This study was conducted to characterise HEV isolates from north India to study the effect of host and viral factors on HEV infection.MethodsSerum samples collected from 536 AVH patients admitted to Department of Medicine, King George's Medical University, Lucknow from July 2016 to June 2017 were screened for anti HEV IgM, anti HAV IgM, HBsAg and anti HCV antibodies using commercial ELISA kits. Samples either positive for anti HEV IgM antibodies (n ?= ?204) or negative for all 4 hepatotropic viruses (n ?= ?37) were enrolled and tested by real time PCR for HEV RNA. HEV RNA positive samples with high viral load were further subjected to nested PCR for amplification of capsid gene. Sequencing and phylogenetic analysis were performed. HEV strains isolated from this study were deposited to GenBank under accession numbers MG571274 to MG571283.ResultsAnti HEV IgM positivity was observed among 38% clinically suspected AVH cases. HEV RNA was detected in 31.8% seropositive HEV cases and additional 3 seronegative cases. Males outnumbered females and the most affected age group was of young adults. Maximum number of cases were seen during the months of June to September. Phylogenetic analysis showed that HEV strains in our study belonged to genotype 1a. Mortality in HEV infected pregnant females was 23.5% as compared to 2.4% in non-pregnant females. Adverse fetal outcome was recorded in 51% of HEV infected pregnancies.ConclusionsHEV genotype 1a is prevalent in our setting. HEV during pregnancy is associated with adverse maternal and fetal outcome.  相似文献   
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Background

Dengue is an emerging public health problem causing serious morbidity and mortality in tropical developing countries. Early, sensitive and specific diagnosis is paramount for clinical decision making. Currently available diagnostic tests are limited in scope and utility. This study highlights applicability of RT-LAMP in dengue diagnosis.

Methods

100 dengue confirmed cases, 100 dengue negative cases and 79 healthy negative controls from dengue epidemic between Sep 2009 to Jul 2011 were included. Dengue cases were profiled using WHO guidelines 2006, haematological and biochemical parameters evaluated and diagnosed using NS1 antigen, IgM and IgG enzyme immunoassay, RT-PCR and RT-LAMP. Positive cases were serotyped, genotyped and various tests were compared.

Results

Mean haematocrit, PT, PTT, platelet count, activated lymphocytes, serum fibrinogen, transaminases, bilirubin, lactate dehydrogenase, protein and sodium were significantly elevated in DHF/DSS as compared to DF. NS1 antigen, RT-PCR and RT-LAMP were sensitive during 1–3 days while μ-capture IgM EIA was specific after 5–7 days of initial infection. DEN-1 genotype III was predominant.

Conclusion

Deranged haematocrit and liver function tests are indicators of the severity of the disease. RT-LAMP is rapid, cost effective, highly sensitive and specific qualitative and quantitative technique which can detect dengue infection in both early and intermediary stages when NS1 antigen titres are not in the detectable range and the IgM antibody titres have just started to rise. Its superiority over existing techniques, amenability for automation and promising utility in low resource healthcare setups and field conditions raise it as the new gold standard for dengue diagnosis.  相似文献   
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Aim: To investigate risk factors of adverse outcome in a cohort of very preterm children treated mainly with nasal continuous positive airway pressure (CPAP) during the neonatal course. Methods: In Denmark, preterm children are treated with nasal CPAP as a first approach to respiratory support. A national prospective study of all infants with a birthweight below 1000 g or a gestational age below 28 wk born in 1994-1995 was initiated to evaluate this approach. Of the 269 surviving children 164 (61%) were not treated with mechanical ventilation in the neonatal period. A follow-up of the children at 5 y of age was conducted. Data from the neonatal period and the 5-y follow-up were analysed. Results: In multivariate analyses including 250 children, a severely abnormal neonatal brain ultrasound scan was predictive of cerebral palsy (OR = 19.9, CI 95%: 6.1-64.8) and intellectual disability (OR = 6.2, CI 95%: 2.3-16.5). A high Clinical Risk Index for Babies (CRIB) score (OR = 2.4, CI 95%: 1.1-5.5) and chronic lung disease (OR = 2.8, CI 95%: 1.2-6.9) were predictive of intellectual disability. In univariate analyses mechanical ventilation was associated with cerebral palsy (OR = 4.3, CI 95%: 1.7-10.8) and intellectual disability (OR = 2.2, CI 95%: 1.2-4.2), but the associations became insignificant in multivariate analyses including chronic lung disease and a severely abnormal ultrasound scan.

Conclusion: The associations between neonatal risk factors and adverse outcome in our cohort were very similar to those found in other cohorts with another initial treatment of respiratory insufficiency. We found no significant adverse effects of mechanical ventilation beyond what could be explained by associations with chronic lung disease and IVH 3-4/PVL.  相似文献   
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OBJECTIVE: The association between hospital volumen and outcome of major cancer surgery is being debated at present. We analysed the outcome of rectal cancer surgery in Denmark during the period 1994-99. METHODS: All patients with a first-time rectal cancer were registered in a national database during the 5-year period. In this observational cohort study, the influence of hospital case volume on resectional procedure, complications, 30-day mortality and 5-year mortality was analysed. RESULTS: The register comprised 5021 patients. Surgery was performed in 27 hospitals with <15 operations per year, 15 hospitals with 15-30 operations per year and 11 hospitals with >30 operations per year. In a multivariate model, the risk of permanent colostomy was significantly increased in the group of low-volume hospitals. On the contrary, volume did not influence the risk of anastomotic leakage, 30-day mortality and 5-year mortality. However, a large variation in 5-year mortality was observed particularly within the low-volume group of hospitals. CONCLUSIONS: In this study, only risk of having a permanent colostomy during surgery for rectal cancer was significantly related to hospital case volume. When individual hospitals were analysed, a large variation in 5-year mortality was observed within the low-volume group of hospitals.  相似文献   
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BACKGROUND: We have previously observed that an increasing time to pregnancy (TTP) is associated with a reduced frequency of twin deliveries in couples not receiving infertility treatment. By using updated information, we assessed the frequencies of dizygotic (DZ) and monozygotic (MZ) twin deliveries as a function of infertility (TTP > 12 months), as well as infertility treatment. METHODS: From the Danish National Birth Cohort (1997-2003), we identified 51 730 fertile couples with TTP 12 months and 5163 infertile couples who conceived after treatment. Information on zygosity, available for part of the cohort (1997-2000), was based on standardized questions on the similarities between the twins at the age of 3-5 years. RESULTS: Compared with fertile couples, the frequency of DZ twin deliveries was lower for infertile couples conceiving naturally (odds ratio 0.4, 95% confidence interval 0.2-0.7) and was much higher for infertile couples conceiving after treatment (17.3, 14.4-20.7). The frequency of DZ twin deliveries decreased with TTP in untreated couples, whereas the frequency of MZ twin deliveries remained constant. CONCLUSIONS: The frequency of DZ twin deliveries decreased with TTP and substantially increased with infertility treatment, whereas MZ twin deliveries remained substantially unchanged.  相似文献   
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