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991.
Studies of healthy adults show that engagement in physical, social, and mental activities is associated with better cognitive outcomes, suggesting that these activities may increase cognitive reserve. Given the prevalence and real-world impact of HIV-associated neurocognitive disorders (HAND), the present study examined the association between neurocognitive outcomes and self-reported proxies for physical exercise, social activity, and mental activity (employment was used as a proxy for mental activity) among 139 HIV-infected adults (M age = 48.7; 48 % age 50+). Participants completed a neuromedical and neuropsychological battery and were classified based on the number of self-reported active lifestyle factors (ALFs; 0 to 3), including physical exercise, social activity, and current employment. The association between ALFs and both demographically adjusted average neuropsychological T-scores and HAND diagnoses was examined. Results revealed that an increased number of ALFs were associated with better global neurocognitive performance as well as a lower prevalence of HAND. These cross-sectional findings suggest that an active engagement in life may bolster neurocognitive functioning, perhaps by enhancing cognitive and/or brain reserve. However, an alternative explanation might be that persons with better neurocognitive functioning are more inclined and able to engage in these life activities. Future studies should utilize neuroimaging methodology, longitudinal data, and interventional approaches to establish cause–effect relationships and uncover the neural mechanisms whereby physical, social, and mental stimulation may protect neurocognition via cognitive reserve among those living with HIV.  相似文献   
992.
We tested whether significant leukocyte infiltration occurs in a mouse model of permanent cerebral ischemia. C57BL6/J male mice underwent either permanent (3 or 24 hours) or transient (1 or 2 hours+22- to 23-hour reperfusion) middle cerebral artery occlusion (MCAO). Using flow cytometry, we observed ∼15,000 leukocytes (CD45+high cells) in the ischemic hemisphere as early as 3 hours after permanent MCAO (pMCAO), comprising ∼40% lymphoid cells and ∼60% myeloid cells. Neutrophils were the predominant cell type entering the brain, and were increased to ∼5,000 as early as 3 hours after pMCAO. Several cell types (monocytes, macrophages, B lymphocytes, CD8+ T lymphocytes, and natural killer cells) were also increased at 3 hours to levels sustained for 24 hours, whereas others (CD4+ T cells, natural killer T cells, and dendritic cells) were unchanged at 3 hours, but were increased by 24 hours after pMCAO. Immunohistochemical analysis revealed that leukocytes typically had entered and widely dispersed throughout the parenchyma of the infarct within 3 hours. Moreover, compared with pMCAO, there were ∼50% fewer infiltrating leukocytes at 24 hours after transient MCAO (tMCAO), independent of infarct size. Microglial cell numbers were bilaterally increased in both models. These findings indicate that a profound infiltration of inflammatory cells occurs in the brain early after focal ischemia, especially without reperfusion.  相似文献   
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Renal transplant recipients are at an increased risk of developing Methicillin‐resistant Staphylococcus aureus due to their immunosuppressed status. Herein, we investigate the incidence of MRSA infection in patients undergoing renal transplantation and determine the effect of MRSA colonisation on renal allograft function and overall mortality. Between January 1st 2007 and December 31st 2012, 1499 consecutive kidney transplants performed in our transplant unit and a retrospective 1:2 matched case‐control study was performed on this patient cohort. The 1‐, 3‐ and 5‐year overall graft survival rates were 100%, 86% and 78%, respectively, in MRSA positive recipients compared with 100%, 100% and 93%, respectively, in the control group (P < 0.05). The 1‐, 3‐ and 5‐year overall patient survival rates were 100%, 97% and 79%, respectively, in MRSA positive recipients compared with 100%, 100% and 95%, respectively, in the control group (P = 0.1). In a multiple logistic regression analysis, colonisation with MRSA pre‐operatively was an independent predictor for renal allograft failure at 5 years (hazard ratio: 4.6, 95% confidence interval: 1–30.7, P = 0.048). These findings demonstrate that the incidence of long‐term renal allograft failure is significantly greater in this patient cohort compared with a matched control population.  相似文献   
994.
The 2007-2010 National Health and Nutrition Examination Survey was used to estimate vitamin D intakes of children 1 to 18 years old in the United States by race/ethnicity, sex, age, and family using 24-hour dietary intake recalls and dietary supplement use questionnaires. We hypothesized that total, dietary, and supplemental vitamin D intakes of children would differ by race/ethnicity, sex, age, and income. Statistical analyses of weighted data were performed using Statistical Analysis Software (V 9.2) to estimate means ± SE. Race and ethnic intake differences controlling for poverty income ratio (PIR), sex, and age were assessed by analysis of covariance. Total (dietary and supplement) vitamin D intake was greater in the high (7.9 ± 0.3 μg/d) vs the medium (6.5 ± 0.3 μg/d) income group, but not the low (7.2 ± 0.2 μg/d) PIR group. Total vitamin D intake of non-Hispanic (NH) white children (8.1 ± 0.2 μg/d) was greater than Hispanic (7.0 ± 0.2 μg/d) and NH black (5.9 ± 0.2 μg/d) children. Total vitamin D intake declined with age, and intake by boys was higher than girls. Only 17.4% of the children consumed supplements containing vitamin D. Overall, mean intake of vitamin D by all children in each age and ethnic group was lower than the estimated average requirement for vitamin D. Public health efforts should encourage consumption of foods high in vitamin D, expand the number of foods fortified, and target health messages to parents to increase use of vitamin D supplements by children.  相似文献   
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In a recent study published in The Journal of Pathology, Barrow-McGee et al described a feasibility study of a real-time ex vivo perfusion model of the axillary lymph nodes (ALNs) from breast cancer patients for immune-oncological investigations. The study showed that perfused ALNs remain viable for up to 24 h, and perfusion of therapeutic antibodies confirmed the ability to reach ALN-resident cells. This work is a highly encouraging demonstration of feasibility for further research into lymphatic system function, with applications to immune function, vaccinations, and cancer. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
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