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The mechanisms by which antidepressant-induced neurochemical changes lead to physiological changes in brain circuitry and ultimately an antidepressant response remain unclear. This study investigated the effects of sertraline, a selective serotonin reuptake inhibitor antidepressant, on corticolimbic connectivity, using functional magnetic resonance imaging (fMRI). In all, 12 unmedicated unipolar depressed patients and 11 closely matched healthy control subjects completed two fMRI scanning sessions at baseline and after 6 weeks. Depressed patients received treatment with sertraline between the two sessions. During each fMRI session, subjects first completed a conventional block-design experiment. Next, connectivity between cortical and limbic regions was measured using correlations of low-frequency blood oxygen level-dependent (BOLD) fluctuations (LFBF) during continuous exposure to neutral, positive, and negative pictures. At baseline, depressed patients had decreased corticolimbic LFBF correlations compared to healthy subjects during the resting state and on exposure to emotionally valenced pictures. At rest and on exposure to neutral and positive pictures, LFBF correlation between the anterior cingulate cortex and limbic regions was significantly increased in patients after treatment. However, on exposure to negative pictures, corticolimbic LFBF correlations remained decreased in depressed patients. The results of this study are consistent with the hypothesis that antidepressant treatment may increase corticolimbic connectivity, thereby possibly increasing the regulatory influence of cortical mood-regulating regions over limbic regions.  相似文献   
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Female cross-border migrants experience elevated risks for HIV, and migrants in South Africa may face additional risks due to the country’s underlying HIV prevalence. These risks may be mitigated by the receipt of social support. A behavioral risk-factor survey was administered using respondent-driven sampling. Multivariable regression models assessed the relationships between social support and two HIV outcomes: HIV serostatus and perceived HIV status. Low social support was not significantly associated with HIV status (aOR?=?1.03, 95?% CI 0.43–2.46), but was significantly related to a perception of being HIV positive (aPR?=?1.36, 95?% CI 1.04–1.78). Age, marital status, and education level were significantly associated with HIV serostatus. Illegal border-crossing, length of time in South Africa, anal sex, and transactional sex were significantly associated with aperception of being HIV positive. Future research should investigate how HIV risks and the receipt of social support change throughout the migration process.  相似文献   
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Adjustments that accompany ageing pose a challenge to the mental health of the elderly. Psychologically based counseling has been documented in Western societies as an appropriate intervention for elderly persons with depressive episodes. There is however very little research documenting how Asian elderly populations experience and benefit from counseling. This study addresses this research gap through a qualitative study based on post-counseling interviews with a sample of 41 elderly persons who received counseling at a dedicated organisation catering to the elderly in Singapore. The qualitative data revealed that clients benefitted from counseling through better emotional management – they received emotional support, found emotional healing and learnt to deal with the emotions associated with grief and loss. Clients also reported that counseling assisted them in decision making processes – older persons were able to conceive of alternatives to their predicament, obtained insights to embark on change, were enabled to take the perspective of others and found validation for their decisions. While many elderly clients greatly appreciated and benefitted from this service, citing demonstrable changes, among the very old such changes were uncommon. Cultural explanations for these differential reports and possible directions for much needed future research are provided.  相似文献   
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