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1.

Introduction

The T allele of a single nucleotide polymorphism (SNP: rs2544390) in lipoprotein receptor-related protein 2 (LRP2) is associated with higher serum urate and risk of gout in Japanese individuals. SNP rs2544390 also interacts with alcohol consumption in determining hyperuricemia in this population. We investigated the association of rs2544390 with gout, and interaction with all types of alcohol consumption in European and New Zealand (NZ) Māori and Pacific subjects, and a Māori study cohort from the East Coast region of NZ’s North Island.

Methods

Rs2544390 was genotyped by Taqman®. From NZ a total of 1205 controls and 1431 gout cases clinically ascertained were used. Publicly available genotype and serum urate data were utilized from the Atherosclerosis Risk in Communities (ARIC) study and the Framingham Heart Study (FHS). Alcohol consumption data were obtained by consumption frequency questions in all study cohorts. Multivariate adjusted logistic regression was done using STATA.

Results

The T allele of rs2544390 was associated with increased risk of gout in the combined Māori and Pacific Island cohort (OR = 1.20, P = 0.009), and associated with gout in the European subjects, but with a protective effect (OR = 0.79, PUnadjusted = 0.02). Alcohol consumption was positively associated with risk of gout in Māori and Pacific subjects (0.2% increased risk/g/week, P = 0.004). There was a non-additive interaction between any alcohol intake and the risk of gout in the combined Māori and Pacific cohorts (PInteraction = 0.001), where any alcohol intake was associated with a 4.18-fold increased risk in the CC genotype group (P = 6.6x10-5), compared with a 1.14-fold increased risk in the CT/TT genotype group (P = 0.40). These effects were not observed in European subjects.

Conclusions

Association of the T-allele with gout risk in the Māori and Pacific subjects was consistent with this allele increasing serum urate in Japanese individuals. The non-additive interaction in the Māori and Pacific subjects showed that alcohol consumption over-rides any protective effect conferred by the CC genotype. Further exploration of the mechanism underlying this interaction should generate new understanding of the biological role of alcohol in gout, in addition to strengthening the evidence base for reduction of alcohol consumption in the management of gout.  相似文献   
2.
BACKGROUND: There are several reports that indicate a linkage between exposure to power frequency (50 - 60 Hz) magnetic fields with abnormalities in the early embryonic development of the chicken. The present study was designed to understand whether power frequency electromagnetic fields could act as an environmental insult and invoke any neurochemical or toxicological changes in developing chick embryo model. METHODS: Fertilized chicken eggs were subjected to continuous exposure to magnetic fields (50 Hz) of varying intensities (5, 50 or 100 microT) for a period of up to 15 days. The embryos were taken out of the eggs on day 5, day 10 and day 15. Neurochemical (norepinephrine and 5-hydroxytryptamine) and amino acid (tyrosine, glutamine and tryptophan) contents were measured, along with an assay of the enzyme glutamine synthetase in the brain. Preliminary toxicological investigations were carried out based on aminotransferases (AST and ALT) and lactate dehydrogenase activities in the whole embryo as well as in the liver. RESULTS: The study revealed that there was a significant increase (p < 0.01 and p < 0.001) in the level of norepinephrine accompanied by a significant decrease (p < 0.01 and p < 0.001) in the tyrosine content in the brain on day 15 following exposure to 5, 50 and 100 microT magnetic fields. There was a significant increase (p < 0.001) in glutamine synthetase activity resulting in the significantly enhanced (p < 0.001) level of glutamine in the brain on day 15 (for 100 microT only). The possible mechanisms for these alterations are discussed. Further, magnetic fields had no effect on the levels of tryptophan and 5-hydroxytryptamine in the brain. Similarly, there was no effect on the activity of either aminotransferases or lactate dehydrogenase in the whole embryo or liver due to magnetic field exposure. CONCLUSIONS: Based on these studies we conclude that magnetic field-induced changes in norepinephrine levels might help explain alterations in the circadian rhythm, observed during magnetic field stress. Also, the enhanced level of glutamine can act as a contributing factor for developmental abnormalities.  相似文献   
3.
4.
Aims Our study was conducted in the Nokrek Biosphere Reserve (NBR) in the Garo hills districts of Meghalaya, Northeast India. Our aim was to assess the effects of human activities on plant diversity,population structure and regeneration.Methods We selected a representative 1.2 hm2 stand in both the core and buffer zones of NBR. Structure and composition were determined by randomly sampling square quadrats, population structure was assessed by determining age structure, and regeneration was assessed by measuring densities of seedling, sapling and adult trees.Important findings More woody species were recorded from the core zone than the buffer zone (87 vs. 81 species), and there were a large number of tropical, temperate, and Sino-Himalayan, Burma-Malaysian and Malayan elements, primitive families and primitive genera. The trees were distributed in three distinct strata,canopy, subcanopy and sapling. Subcanopy and sapling layers had the highest species richness (81% -88% ). Lauraceae and Euphorbiaceae were the dominant families in terms of the number of species, and a large number of families were represented by single species. Most woody species (57 % - 79 % ) were contagiously distributed and had low frequency ( < 20% ). Although stand density was high in the buffer zone, its basal area was low compared to the stand in the core zone. Low similarity and high β-diversity indicate marked differences in species composition of the stands. Shannon diversity index was high in both the stands, while Simpson dominance index was low. The diameter-class distribution for dominant species revealed that the most had a large number of young individuals in their populations. Preponderance of tree seedlings, followed by a steep decline in population density of saplings and adult trees, indicated that the seedling to sapling stage was the most critical in the life cycle of the tree populations. Most species (42 % - 48 % ) had no regeneration,25 % - 35 % had good/fair regeneration, and the rest had poor regeneration or reoccurred as immigrants.  相似文献   
5.
The sucrose proton-cotransporter gene from potato (StSUT1) is mainly expressed in the phloem of mature, exporting leaves. To study the in vivo role of the protein, potato plants were transformed with antisense constructs of the sucrose transporter cDNA under control of the CaMV35S and the rolC promoters, respectively. Both types of transgenic plant develop symptoms characteristic of an inhibition of phloem loading. To determine the level of inhibition, immunological and transport studies were performed. Purified antibodies directed against a peptide from the central loop of SUT1 recognized a transporter with an apparent molecular mass of 47 kDa in leaf plasma membrane vesicles. Antisense repression under control of the non-specific CaMV35S promoter led to a strong reduction in SUT1 protein, whereas no such reduction could be detected when the companion cell-specific rolC promoter was used. Similarily. sucrose uptake in plasma membrane vesicles was reduced by 50–75% in CaMV35S but not in rolC plants. These data suggest that, unlike the rolC promoter, the sucrose transporter is expressed not only in the companion cells but also in other leaf cells. However, inhibition of the transporter by rolC-controlled antisense repression is sufficient to impair phloem loading.  相似文献   
6.
The brown bear has proved a useful model for studying Late Quaternary mammalian phylogeography. However, information is lacking from northern continental Eurasia, which constitutes a large part of the species' current distribution. We analysed mitochondrial DNA sequences (totalling 1943 bp) from 205 bears from northeast Europe and Russia in order to characterize the maternal phylogeography of bears in this region. We also estimated the formation times of the sampled brown bear lineages and those of its extinct relative, the cave bear.
Four closely related haplogroups belonging to a single mitochondrial subclade were identified in northern continental Eurasia. Several haplotypes were found throughout the whole study area, while one haplogroup was restricted to Kamchatka. The haplotype network, estimated divergence times and various statistical tests indicated that bears in northern continental Eurasia recently underwent a sudden expansion, preceded by a severe bottleneck. This brown bear population was therefore most likely founded by a small number of bears that were restricted to a single refuge area during the last glacial maximum. This pattern has been described previously for other mammal species and as such may represent one general model for the phylogeography of Eurasian mammals. Bayesian divergence time estimates are presented for different brown and cave bear clades. Moreover, our results demonstrate the extent of substitution rate variation occurring throughout the phylogenetic tree, highlighting the need for appropriate calibration when estimating divergence times.  相似文献   
7.

Background  

The positive end-expiratory pressure (PEEP) for the mechanical ventilation of small animals is frequently obtained with water seals or by using ventilators developed for human use. An alternative mechanism is the use of an on-off expiratory valve closing at the moment when the alveolar pressure is equal to the target PEEP. In this paper, a novel PEEP controller (PEEP-new) and the PEEP system of a commercial small-animal ventilator, both based on switching an on-off valve, are evaluated.  相似文献   
8.

Background

In the backdrop of conflicting reports (some studies reported adverse outcomes of biomass fuel use whereas few studies reported absence of any association between adverse health effect and fuel use, may be due to presence of large number of confounding variables) on the respiratory health effects of biomass fuel use, this cross sectional survey was undertaken to understand the role of fuel use on pulmonary function.

Method

This study was conducted in a village of western India involving 369 randomly selected adult subjects (165 male and 204 female). All the subjects were interviewed and were subjected to pulmonary function test. Analysis of covariance was performed to compare the levels of different pulmonary function test parameters in relation to different fuel use taking care of the role of possible confounding factors.

Results

This study showed that biomass fuel use (especially wood) is an important factor for deterioration of pulmonary function (particularly in female). FEV1 (p < .05), FEV1 % (p < .01), PEFR (p < .05) and FEF25–75 (p < .01) values were significantly lower in biomass fuel using females than nonusers. Comparison of only biomass fuel use vs. only LPG (Liquefied Petroleum Gas) use and only wood vs. only LPG use has showed that LPG is a safer fuel so far as deterioration of pulmonary function is concerned. This study observes some deterioration of pulmonary function in the male subjects also, who came from biomass fuel using families.

Conclusion

This study concluded that traditional biomass fuels like wood have adverse effects on pulmonary function.  相似文献   
9.

Background

2009 pandemic influenza A/H1N1 (A(H1N1)pdm09) was first detected in the United States in April 2009 and resulted in a global pandemic. We conducted a serologic survey to estimate the cumulative incidence of A(H1N1)pdm09 through the end of 2009 when pandemic activity had waned in the United States.

Methods

We conducted a pair of cross sectional serologic surveys before and after the spring/fall waves of the pandemic for evidence of seropositivity (titer ≥40) using the hemagglutination inhibition (HI) assay. We tested a baseline sample of 1,142 serum specimens from the 2007–2008 National Health and Nutrition Examination Survey (NHANES), and 2,759 serum specimens submitted for routine screening to clinical diagnostic laboratories from ten representative sites.

Results

The age-adjusted prevalence of seropositivity to A(H1N1)pdm09 by year-end 2009 was 36.9% (95%CI: 31.7–42.2%). After adjusting for baseline cross-reactive antibody, pandemic vaccination coverage and the sensitivity/specificity of the HI assay, we estimate that 20.2% (95%CI: 10.1–28.3%) of the population was infected with A(H1N1)pdm09 by December 2009, including 53.3% (95%CI: 39.0–67.1%) of children aged 5–17 years.

Conclusions

By December 2009, approximately one-fifth of the US population, or 61.9 million persons, may have been infected with A(H1N1)pdm09, including around half of school-aged children.  相似文献   
10.
The degree of sexual seed set and the ability to cross were investigated in three taxa of Potentilla section Niveae ( P. chamissonis , P. insularis and P. nivea ) from the Svalbard Archipelago. Emasculated and bagged flowers had little or no seed set, while 71% of the emasculated, bagged and pollinated flowers had some. The taxa are interpreted as pseudogamous apomicts. Parental plants and offspring were subjected to isozyme analysis. Most of the offspring were clones of the mother plant, but 1.7% had bands from the pollen donor. The sexual offspring were all produced by mother plants of P. insularis , which is interpreted as a facultative apomict. Surprisingly, crosses between different taxa gave higher seed to ovule ratios and numbers of sexually produced offspring than crosses within taxa. Some of the sexually produced hybrid offspring had the same kind of hairs on the petioles as their mother taxon, showing that hybrids may not be intermediate in hair characters, which are considered important in the delimitation of these taxa. The results of the present study indicate very close relationships among the investigated plants.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 373−381.  相似文献   
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