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Communication between the amygdala and other brain regions critically regulates sensitivity to threat, which has been associated with risk for mood and affective disorders. The extent to which these neural pathways are genetically determined or correlate with risk-related personality measures is not fully understood. Using functional magnetic resonance imaging, we evaluated independent and interactive effects of the 5-HTTLPR genotype and neuroticism on amygdala functional connectivity during an emotional faces paradigm in 76 healthy individuals. Functional connectivity between left amygdala and medial prefrontal cortex (mPFC) and between both amygdalae and a cluster including posterior cingulate cortex, precuneus and visual cortex was significantly increased in 5-HTTLPR S′ allele carriers relative to LALA individuals. Neuroticism was negatively correlated with functional connectivity between right amygdala and mPFC and visual cortex, and between both amygdalae and left lateral orbitofrontal (lOFC) and ventrolateral prefrontal cortex (vlPFC). Notably, 5-HTTLPR moderated the association between neuroticism and functional connectivity between both amygdalae and left lOFC/vlPFC, such that S′ carriers exhibited a more negative association relative to LALA individuals. These findings provide novel evidence for both independent and interactive effects of 5-HTTLPR genotype and neuroticism on amygdala communication, which may mediate effects on risk for mood and affective disorders.  相似文献   
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Little is known about the perceptions nursing assistants certified (NAC) have related to their occupational health and safety risks and how these perceptions influence the safety precautions taken. The purpose of this study was to describe the perceptions of the occupational health and safety risks perceived by NAC, along with determining the protective mechanisms they used to prevent injury and illness. Ten NAC employed by a skilled nursing facility were interviewed using a semi-structured interview guide. Numerous hazards and protective mechanisms were identified and these were categorized and environmental, physical or cognitive in nature. Based on the NAC perceptions of their occupational hazards, there were a number of areas in which they were ignorant to concepts the administration believed to be readily available. While the facility has a number of health promotion and safety programs already in place, these alone seem inadequate to meet the perceived needs of the NAC. Strategies are needed in three specific areas to address the knowledge deficits and enhance the overall effectiveness of improving the health and safety of the NAC--communication, fostering teamwork, and educational and training opportunities.  相似文献   
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Quality of Life Research - Meeting physical activity (PA) recommendations is positively associated with health-related quality of life (HRQoL), but it is still unclear whether PA (specifically...  相似文献   
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Although protein‐bound uremic compounds have been related to outcome in observational studies, few current dialysis strategies provide more removal of those compounds than standard hemodialysis. We evaluated the evolution of protein‐bound uremic solutes after a switch from high‐flux hemodialysis to postdilution hemodiafiltration (n = 13). We compared predialysis solute concentration at 4, 5, and 9 weeks versus baseline for several protein‐bound compounds and water‐soluble solutes, as well as for β2‐microglobulin. After 9 weeks of postdilution hemodiafiltration, a significant decrease versus baseline could be detected for total concentration of protein‐bound solutes: p‐cresylsulfate (3.98 ± 1.51–3.17 ± 1.77 mg/dL, ?20%, P < 0.01) and 3‐carboxyl‐4‐methyl‐5‐propyl‐2‐furanpropionic acid (0.72 ± 0.52–0.64 ± 0.46 mg/dL, ?11%, P < 0.01). For the other protein‐bound solutes, hippuric acid, indoleacetic acid, and indoxylsulfate, no change in total concentration could be detected. The concentration of the middle molecule, β2‐microglobulin, decreased as well after 9 weeks of postdilution hemodiafiltration (24.7 ± 9.3–18.1 ± 6.7 mg/L, ?27%, P < 0.01). For water‐soluble compounds, no significant change of concentration was found. Postdilution hemodiafiltration in comparison to high‐flux hemodialysis provided significant reduction of predialysis concentration of protein‐bound compounds, especially those with the highest protein binding, and of β2‐microglobulin, by ?11 to ?27% in 9 weeks.  相似文献   
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The purpose of this study was to evaluate the relevance of long-term endothelial cell culture as a model system of vascular ageing. Micro- and macrovascular endothelial cells were serially passaged until replicative senescence and their ability to form tube-like structures when cultured on Matrigel was assessed throughout their lifespan. For both cell types low passage cultures adopted a homogeneous cobblestone morphology, while senescent cultures were extremely heterogeneous. Furthermore, both cell types showed a reduction in tube formation ability with in vitro ageing, which is in accordance with the reduction in angiogenic potential observed with ageing in vivo. Examination of senescence associated β-galactosidase activity revealed an increased activity in cells forming tubes as compared to cells cultured on plastic, which could be attributed to an increased lysosomal content of cells undergoing tube formation. As this increased senescence associated β-galactosidase activity was unrelated to the replicative age of the cells, senescence associated β-galactosidase activity may not be a relevant senescence marker for differentiating endothelial cells. The age-related reduction in tube formation ability suggested that long-term culture of endothelial cells may be a valid model system of vascular ageing, which makes it an ideal platform for high throughput screening of compounds influencing angiogenesis.  相似文献   
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Diisononyl phthalate (DINP) is a plasticizer abundantly used in consumer products as a substitute for other plasticizers prohibited in certain products due to reproductive toxicity. As anti-androgenic effects of DINP are suspected, DINP effects on reproduction and sexually dimorphic behavior were studied. Pregnant Wistar rats were gavaged from gestation day 7 to postnatal day (PND) 17 with vehicle, 300, 600, 750 or 900 mg DINP/kg bw/day. In fetal testes histopathological effects typical of phthalates were observed. In male offspring, DINP caused increased nipple retention, reduced anogenital distance, reduced sperm motility and increased sperm count. DINP affected spatial learning as female offspring performed better than controls and similarly to control males in the Morris Water Maze, indicating masculinization of behavior in DINP exposed females. These results show that DINP causes anti-androgenic effects on reproductive development, though less potent than DEHP, DBP and BBP, and further safety evaluation of DINP appears warranted.  相似文献   
100.
Aleutian mink disease virus (AMDV) is a severe progressive disease causing multiple different clinical syndromes in mink. In Denmark, the disease is notifiable and under official control. The control programme, based on serological screening, has confined successfully AMDV to the northern part of Denmark. However, re-infections and new introductions of virus into farms require a confirmatory virological test to verify the positive test results of single animals and ultimately to investigate disease transmission. A one step PCR amplifying a 374-base fragment of the NS1 gene of AMDV was compared to the counter-current immune electrophoresis (CIE) routinely used in the serological screening programme. Mink organs (n = 299) obtained from 55 recently infected farms and 8 non-infected farms from 2008 to 2010 were tested by PCR, and the results were found to have a high correlation with the serological status of the mink. The relative diagnostic sensitivity of the PCR was 94.7%, and the relative diagnostic specificity was 97.9% when read in parallel with the CIE. PCR positive samples were sequenced and phylogenetic analysis revealed high similarity within the analysed AMDV strains and to AMDV strains described previously.  相似文献   
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