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Prior studies have demonstrated associations between beta‐adrenergic receptor (βAR) polymorphisms and left ventricular dysfunction—an important cause of allograft nonutilization for transplantation. We hypothesized that βAR polymorphisms predispose donor hearts to LV dysfunction after brain death. A total of 1043 organ donors managed from 2001–2006 were initially studied. The following βAR single nucleotide polymorphisms were genotyped: β1AR 1165C/G (Arg389Gly), β1AR 145A/G (Ser49Gly), β2AR 46G/A (Gly16Arg) and β2AR 79C/G (Gln27Glu). In multivariable regression analyses, the β2AR46 SNP was significantly associated with LV systolic dysfunction, with each minor allele additively decreasing the odds for LV ejection fraction <50%. The β1AR1165 and β2AR46 SNPs were associated with higher dopamine requirement during the donor management period: donors with the GG and AA genotypes had ORs of 2.64 (95% CI 1.52–4.57) and 2.70 (1.07–2.74) respectively for requiring >10 μg/kg/min of dopamine compared to those with the CC and GG genotypes. However, no significant associations were found between βAR SNPs and cardiac dysfunction in 364 donors managed from 2007–2008, perhaps due to changes in donor management, lack of power in this validation cohort, or the absence of a true association. βAR polymorphisms may be associated with cardiac dysfunction after brain death, but these relationships require further study in independent donor cohorts.  相似文献   
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Rice has become a model cereal plant for molecular genetic research. Rice has the most comprehensive molecular linkage maps with more than 2000 DNA markers and shows synteny and colinearity with the maps of other cereal crops. Until now, however, no information was available about the positions of centromeres and arm locations of markers on the molecular linkage map. Secondary and telotrisomics were used to assign restriction fragment length polymorphism markers to specific chromosome arms and thereby to map the positions of centromeres. More than 170 restriction fragment length polymorphism markers were assigned to specific chromosome arms through gene dosage analysis using the secondary and telotrisomics and the centromere positions were mapped on all 12 linkage groups. The orientations of seven linkage groups were reversed to fit the "short arm on top" convention and the corrected map is presented.  相似文献   
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Impaired kidney function often accompanies heart failure (HF) and is associated with a worse prognosis. This post hoc analysis of the Treating to New Targets (TNT) trial examined whether the observed decrease in HF hospitalizations with high- compared to low-dose atorvastatin could be related to improvements in kidney function. Of 10,001 TNT participants, 9,376 had estimated glomerular filtration rate (eGFR) measurements at baseline and 1 year and were included in this analysis. The association of change in year-1 eGFR and subsequent HF hospitalization was examined using Cox regression models. In total 218 participants developed subsequent HF hospitalization. Little change in eGFR occurred over 1 year in the atorvastatin 10-mg group, whereas eGFR improved in the 80-mg group by 1.48 ml/min/1.73 m(2) (95% confidence interval 1.29 to 1.67, p <0.0001). Subsequent HF was preceded by a decrease in eGFR over 1 year compared to modest improvement in those without subsequent HF (-0.09 ± 7.89 vs 0.81 ± 6.90 ml/min/1.73 m(2), p = 0.0015). After adjusting for baseline eGFR, each 5-ml/min/1.73 m(2) increase in eGFR at 1 year was associated with a lower risk of subsequent HF hospitalization (hazard ratio 0.85, 95% confidence interval 0.77 to 0.94, p = 0.002). This relation was independent of treatment effect or change in low-density lipoprotein cholesterol level at 1 year. In conclusion, treatment with high- compared to low-dose atorvastatin was associated with improvement in eGFR at 1 year, which was related to a decrease in subsequent HF hospitalization. This suggests that improvement in kidney function may be related to the beneficial effect of high-dose atorvastatin on HF hospitalization.  相似文献   
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Rice yields decline with higher night temperature from global warming   总被引:52,自引:0,他引:52  
The impact of projected global warming on crop yields has been evaluated by indirect methods using simulation models. Direct studies on the effects of observed climate change on crop growth and yield could provide more accurate information for assessing the impact of climate change on crop production. We analyzed weather data at the International Rice Research Institute Farm from 1979 to 2003 to examine temperature trends and the relationship between rice yield and temperature by using data from irrigated field experiments conducted at the International Rice Research Institute Farm from 1992 to 2003. Here we report that annual mean maximum and minimum temperatures have increased by 0.35 degrees C and 1.13 degrees C, respectively, for the period 1979-2003 and a close linkage between rice grain yield and mean minimum temperature during the dry cropping season (January to April). Grain yield declined by 10% for each 1 degrees C increase in growing-season minimum temperature in the dry season, whereas the effect of maximum temperature on crop yield was insignificant. This report provides a direct evidence of decreased rice yields from increased nighttime temperature associated with global warming.  相似文献   
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Background

Water quality testing is critical for guiding water safety management and ensuring public health. In many settings, however, water suppliers and surveillance agencies do not meet regulatory requirements for testing frequencies. This study examines the conditions that promote successful water quality monitoring in Africa, with the goal of providing evidence for strengthening regulated water quality testing programs.

Methods and findings

We compared monitoring programs among 26 regulated water suppliers and surveillance agencies across six African countries. These institutions submitted monthly water quality testing results over 18 months. We also collected qualitative data on the conditions that influenced testing performance via approximately 821?h of semi-structured interviews and observations. Based on our qualitative data, we developed the Water Capacity Rating Diagnostic (WaterCaRD) to establish a scoring framework for evaluating the effects of the following conditions on testing performance: accountability, staffing, program structure, finances, and equipment & services. We summarized the qualitative data into case studies for each of the 26 institutions and then used the case studies to score the institutions against the conditions captured in WaterCaRD. Subsequently, we applied fuzzy-set Qualitative Comparative Analysis (fsQCA) to compare these scores against performance outcomes for water quality testing. We defined the performance outcomes as the proportion of testing Targets Achieved (outcome 1) and Testing Consistency (outcome 2) based on the monthly number of microbial water quality tests conducted by each institution. Our analysis identified motivation & leadership, knowledge, staff retention, and transport as institutional conditions that were necessary for achieving monitoring targets. In addition, equipment, procurement, infrastructure, and enforcement contributed to the pathways that resulted in strong monitoring performance.

Conclusions

Our identification of institutional commitment, comprising motivation & leadership, knowledge, and staff retention, as a key driver of monitoring performance was not surprising: in weak regulatory environments, individuals and their motivations take-on greater importance in determining institutional and programmatic outcomes. Nevertheless, efforts to build data collection capacity in low-resource settings largely focus on supply-side interventions: the provision of infrastructure, equipment, and training sessions. Our results indicate that these interventions will continue to have limited long-term impacts and sustainability without complementary strategies for motivating or incentivizing water supply and surveillance agency managers to achieve testing goals. More broadly, our research demonstrates both an experimental approach for diagnosing the systems that underlie service provision and an analytical strategy for identifying appropriate interventions.  相似文献   
10.
Anogenital squamous cell carcinoma has been noted with increased frequency in HIV-seropositive patients. Verrucous carcinoma is a variant of squamous cell carcinoma that tends to be locally invasive and non-metastasizing. Although human papilloma-virus (HPV) has been strongly implicated in other squamous neoplasms, it has been variably associated with verrucous carcinoma and has not been examined in these lesions in the HIV-positive population. The aim of this study was to examine the association of HPV with anal verrucous carcinoma in patients with the human immunodeficiency virus (HIV). HPV DNA in situ hybridization for HPV Types 6/11, 16/18, and 31/33/35 was performed on formalin-fixed, paraffin-embedded tissue from six cases of verrucous carcinoma and four cases of condyloma acuminatum in perianal specimens from HIV-seropositive patients. HPV DNA sequences were identified in five of six cases of verrucous carcinoma and in all cases of condyloma acuminatum. Of the five verrucous carcinomas that harbored detectable HPV DNA, four contained HPV 6/11 and two contained HPV 16/18. One contained both HPV 6/11 and HPV 16/18. All four cases of condyloma acuminatum were positive for HPV 6/11. One patient included in this series had three chronologically separate verrucous carcinomas. The initial lesion was negative for HPV DNA. Subsequent verrucous carcinomas were positive for HPV type 6/11 and type 16/18, respectively. The data presented support the concept that verrucous carcinoma in the HIV-seropositive population is associated with HPV, which may indeed play an important role in its pathogenesis.  相似文献   
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