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71.
The role of beta-chemokines in controlling HIV replication in vivo is still controversial. Therefore, the association between HIV-1 plasma viral load and the capacity of CD4(+) and CD8(+) T cells to produce beta-chemokines was studied in 28 antiretroviral drug-na?ve HIV-1-infected female sex workers in Abidjan, C?te d'Ivoire. Percentages of beta-chemokine-positive T cells were measured in peripheral blood mononuclear cells by flow cytometry after intracellular staining for RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta. HIV-1-infected subjects had higher percentages of MIP-1alpha- and MIP-1beta-positive CD4(+) and CD8(+) T cells (p < 0.02) and of RANTES-positive CD8(+) T cells (p = 0.054) than uninfected controls. Percentages of RANTES- and MIP-1beta-positive CD8(+) T cells correlated directly with HIV-1 plasma viral load (p < 0.02). Percentages of beta-chemokine-positive CD4(+) and CD8(+) T cells correlated directly with percentages of HLA-DR-positive T cells (p < 0.02) and inversely (except RANTES in CD4(+) T cells) with absolute numbers of CD4(+) T cells (p < 0.05) in peripheral blood. These data indicate that increased percentages of beta-chemokine-producing T cells in HIV-1-infected subjects correlate with disease progression and are a sign of viremia-driven chronic T cell activation.  相似文献   
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Cellular factors that may protect against human immunodeficiency virus (HIV) infection were investigated in 27 HIV-exposed seronegative (ESN) female sex workers (FSWs) and 27 HIV-seronegative female blood donors. Compared with blood donors, ESN FSWs had significantly decreased expression levels of C-X-C chemokine receptor 4 (CXCR4), but not of C-C chemokine receptor 5, on both memory (P<.001) and naive (P=.041) CD4(+) T cells. CXCR4 down-regulation was associated with prolonged duration of commercial sex work by ESN FSWs. CD38 expression on CD8(+) T cells was significantly increased among ESN FSWs, compared with that among blood donors (P=.017). There were no differences in HLA-DR and CD62L expression between blood donors and ESN FSWs. Proportions of T cells producing the beta-chemokines RANTES (regulated on activation, normally T cell-expressed and -secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta or the cytokines interleukin (IL)-2, IL-4, interferon-gamma, and tumor necrosis factor-alpha, were similar in the 2 groups. These data indicate that ESN FSWs differ from HIV-seronegative female blood donors with respect to immunological factors that have no clear protective potential against HIV transmission.  相似文献   
74.
The coronavirus disease 2019 pandemic presents unprecedented challenges for the health care system. The pressure on health care staff continues to intensify, accentuated by the confinement (lockdown) of the population and the unprecedented duration of this emergency. Separately and especially together, overwork, degraded conditions of care because of the never-ending emergency, and the risk of exposure to the virus can lead to acute psychological distress or signs of burnout.This original program was developed at Cochin Hospital in Paris, France to prevent these potentially dramatic psychological consequences, support the medical staff, and identify those most affected to offer them specific care. A program and a space for relaxation and support for hospital caregivers by hospital caregivers, the Port Royal Bulle (the Bubble) offers these workers help in decompression and relaxation. It combines a warm and caring welcome that promotes attention, listening, conversations, and exchanges as needed, empathetic support, and the ability to participate in soothing, relaxing, or low-impact physical activities. It takes care of caregivers. The Bubble is a program that is simple to set up and that appears to meet professionals' expectations. Making it permanent and enlarging its scale, as a complement to existing programs, might help to support health care personnel in their work.  相似文献   
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Background

Depressive and anxiety disorders (DAD) have become a major public health problem. Multiple trauma is known to increase the risk of DAD through a sensitization mechanism. We investigate the hypothesis that resilience is a mediator of this mechanism.

Methods

Former Hidden Children (FHC), the Jewish youths who spent World War II in various hideaway shelters across Nazi-occupied Europe, were compared with a control group. In each group, we measured the presence of multiple traumas, the resilience with the Resilience Scale for Adults, which has a six factors solution, and the DAD with the Hopkins Symptoms Checklist. We test a mediated moderation model with childhood trauma as the predictor; Later trauma as the moderator; Resilience as the mediator; and DAD as the outcome variable.

Results

Results are consistent with a sensitization model of DAD mediated by resilience: confrontation with a primary trauma during childhood followed by secondary trauma(s) after childhood damages resilience, which, in turn, results in higher level of DAD.

Limitations

We are unable to differentiate if the sensitization process is a consequence of the nature of the trauma endured by FHC (long-standing exposure to extreme external events) or a consequence of the fact that this first trauma occurred during childhood.

Conclusions

Resilience construct is multi-factorial and a limited damaging of some of the factors is sufficient to lead to DAD even if other factors remain unaltered. Resilience can be altered by multiple traumas and, therefore, needs to be bolstered in therapy sessions.  相似文献   
78.
Mild cognitive impairment (MCI) is a clinical condition that often precedes Alzheimer disease (AD). Compared with apolipoprotein E-ε3 (APOE3), the apolipoprotein E-ε4 (APOE4) allele is associated with an increased risk of developing MCI and spatial navigation impairments. In MCI, the entorhinal cortex (EC), which is the main innervation source of the dentate gyrus, displays partial neuronal loss. We show that bilateral partial EC lesions lead to marked spatial memory deficits and reduced synaptic density in the dentate gyrus of APOE4 mice compared with APOE3 mice. Genotype and lesion status did not affect the performance in non-navigational tasks. Thus, partial EC lesions in APOE4 mice were sufficient to induce severe spatial memory impairments and synaptic loss in the dentate gyrus. In addition, lesioned APOE4 mice showed no evidence of reactional increase in cholinergic terminals density as opposed to APOE3 mice, suggesting that APOE4 interferes with the ability of the cholinergic system to respond to EC input loss. These findings provide a possible mechanism underlying the aggravating effect of APOE4 on the cognitive outcome of MCI patients.  相似文献   
79.
Melioidosis is a severe gram-negative infection caused by the facultative intracellular bacterium Burkholderia pseudomallei, which is responsible for a broad spectrum of symptoms in both humans and animals. No licensed vaccine currently exists. This study evaluated the protective effect of a monoclonal antibody (Mab Ps6F6) specific to B. pseudomallei exopolysaccharide in an outbred murine model of sub-acute melioidosis. When administered before the infectious challenge, Ps6F6 significantly increased resistance to infection and restrained bacterial burden in the spleen over a 30-days period. Patterns of IFN-γ production were similar in the treated and non treated groups of mice. However, Ps6F6 lowered IFN-γ levels over the duration of the assay period, except on day 1, suggesting a transient and rapid production of IFN-γ under Ps6F6 control. Minor but persisting increases occurred in IL-12 levels while TNF-α was detected only in the controls at the later stages of infection. No IL-10 secretion was detected in both groups of mice. These data suggest that passive prophylaxis with Mab Ps6F6 provide a moderate and transient induction of inflammatory responses in infected mice but failed to trigger a sterilizing protective immunity.  相似文献   
80.
The present work aimed to treat a polyethylene terephthalate (PET) surface to make the biomaterial more ‘attractive’ in terms of attachment and shear stress response to endothelial cells with a view to possible applications in vascular grafting. A surface wet-chemistry protocol was applied to graft track-etched PET membranes with RGD peptidomimetics based on the tyrosine template and active at the nano-level vs. isolated human αvβ3 receptor, which was monitored by X-ray photoelectron spectroscopy, contact angle measurement and atomic force microscopy for characterization. A primary culture of human saphenous vein endothelial cells was used before and after sterilization of the membranes (heat treatment or γ-ray irradiation) to test the benefit of grafting. The optimal surface concentrations of grafted molecules were around 50?pmol/cm². Compared to GRGDS, the peptidomimetics promoted cell attachment with similar or slightly better performances. Endothelialized grafted supports were further exposed to 2?h of shear stress mimicking arterial conditions. Cells were lost on non-grafted PET whereas cells on grafted polymers sterilized by γ-ray irradiation withstood forces with no significant difference in focal contacts. At the mRNA level, cells on functionalized PET were able to respond to shear stress with NFkB upregulation. Thus, grafting of peptidomimetics as ligands of the αvβ3 integrin could be a relevant strategy to improve the adhesion of human endothelial cells and to obtain an efficient endothelialized PET for the surgery of small-diameter vascular prostheses.  相似文献   
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