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Background

Enteric fever is an endemic problem in Nepal and Widal agglutination test is widely used for its diagnosis but a normal baseline titer in healthy population and cutoff values have not been established.

Methods

We measured average baseline antibody titers against "O" and "H" antigens of Salmonella enterica serotype Typhi and "H" antigens of serotypes Paratyphi A and Paratyphi B among apparently healthy blood donors in Nepal. The antibody titers were measured using Standard Widal Confirmatory Quantitative Tube test.

Results

Among the 100 blood samples collected from healthy volunteers, 62 individuals had significant antibody titers (≥ 1:20) against one of the four antigens against S. enterica. Among 54 samples with an anti-O titer against serotype Typhi, 15 and 36 samples had titers of ≥ 1:60 and ≥ 1:40, respectively. A significant proportion (12% of all) had anti-O titer of ≥ 1:80. Similarly, among the 59 samples demonstrating anti-H titers of ≥ 1:20 to S. enterica serotype Typhi, 29 had a titer of ≥ 1:80 and 12 had 1:160. For S. enterica serotypes Paratyphi A and B, anti-H titers of ≥ 1:20 were found only in 12% and 3%, respectively, of all samples tested.

Conclusion

When a single Widal agglutination titer is used for the diagnosis of enteric fever, it will be more appropriate to change the currently used cutoff levels against S. enterica serotype Typhi to > 1:80 for anti-O and > 1:160 for anti-H titers for Nepal.  相似文献   
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Introduction

Self-rated health (SRH) predicts chronic disease morbidity including cardiovascular disease (CVD). In a population-based cohort, we examined the association between SRH and incident CVD and whether this association was independent of socio-demographic, clinical and behavioural participant characteristics.

Methods

Population-based prospective cohort study (European Prospective Investigation of Cancer-Norfolk). 20,941 men and women aged 39–74 years without prevalent CVD attended a baseline health examination (1993–1998) and were followed for CVD events/death until March 2007 (mean 11 years). We used a Cox proportional hazards model to quantify the association between baseline SRH (reported on a four point scale – excellent, good, fair, poor) and risk of developing CVD at follow-up after adjusting for socio-demographic, clinical and behavioural risk factors.

Results

Baseline SRH was reported as excellent by 17.8% participants, good by 65.1%, fair by 16.0% and poor by 1.2%. During 225,508 person-years of follow-up, there were 55 (21.2%) CVD events in the poor SRH group and 259 (7.0%) in the excellent SRH group (HR 3.7, 95% CI 2.8–4.9). The HR remained significant after adjustment for behavioural risk factors (HR 2.6, 95% CI 1.9–3.5) and after adjustment for all socio-demographic, clinical and behavioural risk factors (HR 3.3, 95% CI 2.4–4.4). Associations were strong for both fatal and non-fatal events and remained strong over time.

Conclusions

SRH is a strong predictor of incident fatal and non-fatal CVD events in this healthy, middle-aged population. Some of the association is explained by lifestyle behaviours, but SRH remains a strong predictor after adjustment for socio-demographic, clinical and behavioural risk factors and after a decade of follow-up. This easily accessible patient-centred measure of health status may be a useful indicator of individual and population health for those working in primary care and public health.  相似文献   
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Key message

The Ror1 gene was fine-mapped to the pericentric region of barley chromosome 1HL.

Abstract

Recessively inherited loss-of-function alleles of the barley (Hordeum vulgare) Mildew resistance locus o (Mlo) gene confer durable broad-spectrum disease resistance against the obligate biotrophic fungal powdery mildew pathogen Blumeria graminis f.sp. hordei. Previous genetic analyses revealed two barley genes, Ror1 and Ror2, that are Required for mlo-specified resistance and basal defence. While Ror2 was cloned and shown to encode a t-SNARE protein (syntaxin), the molecular nature or Ror1 remained elusive. Ror1 was previously mapped to the centromeric region of the long arm of barley chromosome 1H. Here, we narrowed the barley Ror1 interval to 0.18 cM and initiated a chromosome walk using barley yeast artificial chromosome (YAC) clones, next-generation DNA sequencing and fluorescence in situ hybridization. Two non-overlapping YAC contigs containing Ror1 flanking genes were identified. Despite a high degree of synteny observed between barley and the sequenced genomes of the grasses rice (Oryza sativa), Brachypodium distachyon and Sorghum bicolor across the wider chromosomal area, the genes in the YAC contigs showed extensive interspecific rearrangements in orientation and order. Consequently, the position of a Ror1 homolog in these species could not be precisely predicted, nor was a barley gene co-segregating with Ror1 identified. These factors have prevented the molecular identification of the Ror1 gene for the time being.  相似文献   
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Background

People who rate their health as poor experience higher all-cause mortality. Study of disease-specific association with self-rated health might increase understanding of why this association exists.

Objectives

To estimate the strength of association between self-rated health and fatal and non-fatal cardiovascular disease.

Methods

A comprehensive search of PubMed MEDLINE, EMBASE, CINAHL, BIOSIS, PsycINFO, DARE, Cochrane Library, and Web of Science was undertaken during June 2013. Two reviewers independently searched databases and selected studies. Inclusion criteria were prospective cohort studies or cohort analyses of randomised trials with baseline measurement of self-rated health with fatal or non-fatal cardiovascular outcomes. 20 studies were pooled quantitatively in different meta-analyses. Study quality was assessed using Newcastle-Ottawa scales.

Results

‘Poor’ relative to ‘excellent’ self-rated health (defined by most extreme categories in each study, most often’ poor’ or ‘very poor’ and ‘excellent’ or ‘good’) was associated over a follow-up of 2.3–23 years with cardiovascular mortality in studies: where varying degrees of adjustments had been made for cardiovascular disease risk (HR 1.79 (95% CI 1.50 to 2.14); 15 studies, I2 = 71.24%), and in studies reporting outcomes in people with pre-existing cardiovascular disease or ischaemic heart disease symptoms (HR 2.42 (95% CI 1.32 to 4.44); 3 studies; I2 = 71.83%). ‘Poor’ relative to ‘excellent’ self rated health was also associated with the combined outcome of fatal and non-fatal cardiovascular events (HR 1.90 (95% CI 1.26 to 2.87); 5 studies; I2 = 68.61%), Self-rated health was not significantly associated with non-fatal cardiovascular disease outcomes (HR 1.66 (95% CI 0.96 to 2.87); 5 studies; I2 = 83.60%).

Conclusions

Poor self rated health is associated with cardiovascular mortality in populations with and without prior cardiovascular disease. Those with current poor self-rated health may warrant additional input from health services to identify and address reasons for their low subjective health.  相似文献   
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The northeast region of India, considered as 'hot spot' of biodiversity, having unique ecological environment with hot and high-humidity conditions, has given rise to the world's hottest chilli, 'Bhut Jolokia', which is at least two times hotter than Red Savina Habanero in terms of Scoville heat units (SHU). This study was undertaken to determine the distinctiveness of 'Bhut Jolokia' from Capsicum frutescens or Capsicum chinense through sequencing of the ribosomal RNA (rRNA) gene-internal transcribed ((ITS) region along with its phylogenetic analysis. Although a compensatory base change (CBC) in the ITS2 region was not observed between the closely related species of C. frutescens and C. chinense when compared with Bhut Jolokia; phylogenetic analysis using ITS1, 5.8S and ITS2 sequences indicated a distinct clade for all the accessions of 'Bhut Joloikia', while C. frutescens and C. chinense occupied discrete lineages. Further, a unique 13-base deletion was observed in all the representative accessions of 'Bhut Jolokia', making it distinct from all other members within the genus and beyond. The degree of genetic variations along with its extreme pungency might be related to ambient environmental factors of northeastern India.  相似文献   
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Formation mechanism of laser-induced spontaneous periodic nanostructures in thin light-sensitive AgCl waveguide films, doped by silver nanoparticles, is studied. It is found that the initial size, geometry, and surface coverage parameters of Ag nanoparticles instate preconditions for the nanostructure formation. These parameters play essential roles in coupled nanoplasmon excitation in silver nanoclusters, which in turn influences scattering of the incident light from the silver clusters. Some parts of the scattered light propagate as waveguide modes in the film and interference with the incident light. Afterward, migration of the Ag nanoparticles into the minima of the interference pattern forms the nanostructure. Simultaneously, excitation of coupled nanoplasmons in the neighboring clusters enhances the scattered light intensity. It is observed that longer exposure results in destruction of the formed nanostructures, because of creation of electrical joint between agglomerated clusters in the interference pattern’s minima, which leads to weakening of the TE mode excitation and, consequently, domination of the Gaussian profile of the incident light. This leads to the deceleration of the self-organized nanostructure development, growth rate, and quality. We have found that competition between the Gaussian profile of the incident laser field and the interference field causes a finally saturating oscillatory behavior of the self-organizing process.  相似文献   
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