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991.
We evaluated the implementation process of Richmond, California’s citywide smoke-free multiunit housing ordinance. We conducted semistructured focus groups with multiunit housing tenants, owners, and managers. Residents understood the harms of secondhand smoke but lacked accurate information about the ordinance and questioned its enforceability. They shared concerns that the city lacked cessation resources for smokers wishing to quit because of the ordinance. To increase compliance with the ordinance, tenants, owners, and managers need accurate information.Implementing smoke-free multiunit housing (MUH) policies is the most effective way to protect MUH residents from secondhand smoke exposure.1,2 We have discussed how MUH tenants, owners, and managers view the implementation of Richmond, California’s citywide smoke-free MUH ordinance and potential barriers to its equitable implementation across the city’s diverse neighborhoods.The majority (78%) of Richmond’s 106 516 residents are ethnic minorities; 38% of Richmond’s population live in MUH residences.3,4 In 2009, Richmond passed an ordinance to prohibit the smoking of any tobacco product or marijuana in residential dwellings containing 2 or more units; it was fully implemented in 2011.5  相似文献   
992.
The upsurge of West Nile virus (WNV) human infections in 2012 suggests that the US can expect periodic WNV outbreaks in the future. Availability of safe and effective vaccines against WNV in endemic areas, particularly for aging populations that are at high risk of West Nile neuroinvasive disease (WNND), could be beneficial. WN/DEN4Δ30 is a live, attenuated chimeric vaccine against WNV produced by replacement of the genes encoding the pre-membrane and envelope protein genes of the vaccine virus against dengue virus type 4 (DEN4Δ30) with corresponding sequences derived from a wild type WNV. Following intrathalamic inoculation of nonhuman primates (NHPs), a comprehensive neuropathogenesis study was performed and neurovirulence of WN/DEN4Δ30 vaccine candidate was compared to that of two parental viruses (i.e., WNV and DEN4Δ30), as well as to that of an attenuated flavivirus surrogate reference (i.e., yellow fever YF 17D). Clinical and virological data, as well as results of a semi-quantitative histopathological analysis, demonstrated that WN/DEN4Δ30 vaccine is highly attenuated for the central nervous system (CNS) of NHPs in comparison to a wild type WNV. Importantly, based on the virus replicative ability in the CNS of NHPs and the degree of induced histopathological changes, the level of neuroattenuation of WN/DEN4Δ30 vaccine was similar to that of YF 17D, and therefore within an acceptable range. In addition, we show that the DEN4Δ30 vaccine tested in this study also has a low neurovirulence profile. In summary, our results demonstrate a high level of neuroattenuation of two vaccine candidates, WN/DEN4Δ30 and DEN4Δ30. We also show here a remarkable sensitivity of our WNV-NY99 NHP model, as well as striking resemblance of the observed neuropathology to that seen in human WNND. These results support the use of this NHP model for translational studies of WNV neuropathogenesis and/or testing the effectiveness of vaccines and therapeutic approaches.  相似文献   
993.
The spatial components of a visual scene are processed neurally in a sequence of coarse features followed by fine features. This coarse‐to‐fine temporal stream was initially considered to be a cortical function, but has recently been demonstrated in the dorsal lateral geniculate nucleus. The goal of this study was to test the hypothesis that coarse‐to‐fine processing is present at earlier stages of visual processing in the retinal ganglion cells that supply lateral geniculate nucleus (LGN) neurons. To compare coarse‐to‐fine processing in the cat's visual system, we measured the visual responses of connected neuronal pairs from the retina and LGN, and separate populations of cells from each region. We found that coarse‐to‐fine processing was clearly present at the ganglion cell layer of the retina. Interestingly, peak and high‐spatial‐frequency cutoff responses were higher in the LGN than in the retina, indicating that there was a progressive cascade of coarse‐to‐fine information from the retina to the LGN to the visual cortex. The analysis of early visual pathway receptive field characteristics showed that the physiological response interplay between the center and surround regions was consistent with coarse‐to‐fine features and may provide a primary role in the underlying mechanism. Taken together, the results from this study provided a framework for understanding the emergence and refinement of coarse‐to‐fine processing in the visual system.  相似文献   
994.
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   
995.
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   
996.
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   
997.
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   
998.
999.
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   
1000.
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