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1.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
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OBJECTIVE: To study the feelings of HIV infected mothers during the perinatal period regarding circumstances of HIV diagnosis, disclosure to partner and fear of contamination. POPULATION AND METHODS: A study based upon personal interviews was carried out from November 2003 to January 2004 upon routine pediatric outpatient visits for infants born to HIV positive mothers. RESULTS: This study included 54 women of which 70% were from Sub-Saharan Africa. Fifty-nine per cent discovered their HIV status during a pregnancy. Seventy-seven per cent of partners were informed of maternal status. Among the women reluctant to inform their partner, the main reasons given were fear of violence and separation. Seventy-two per cent of interviewed women refused their spouses to be informed by the medical staff. Medical care during pregnancy (moral support, delivery) was judged as good by a majority of women (90%) who found the behavior of the staff mostly satisfactory. Final child serology remains the most definitive test for mothers, 47% of whom fear the risk of a potential postnatal contamination of their children. CONCLUSION: In these isolated women, many of whom have recently discovered their HIV status, a multidisciplinary approach including psychosocial support is essential.  相似文献   
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The distribution of dopamine D1 receptors has been determined in post mortem human brain tissues using in vitro receptor autoradiography, with ([3H]N-methyl) SCH 23390 as ligand. The highest densities of dopamine D1 sites were seen in the nucleus caudatus, putamen, globus pallidus pars medialis and substantia nigra. Intermediate densities were associated with the amygdala, mammillary bodies, cerebral cortex and CA1. The remaining part of the hippocampus as well as the diencephalon, brainstem and cerebellum contained low levels of [3H]SCH 23390 binding sites. The distribution of D1 receptors in the human brain closely resembles that reported for the rat brain. In addition, there was a good correlation between the anatomical localization of D1 sites and the distribution of dopaminergic nerve terminals in the central nervous system. The densities of D1 receptors in the human brain were observed to markedly decrease with age during the first decades of life. However, no further modifications were found beyond the age of 40 years. We did not observe any significant influence of other parameters such as gender and post mortem delay in our samples.  相似文献   
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BACKGROUND: Pregnancy is associated with increased susceptibility to malaria. It is generally agreed that this increased risk ends with delivery, but the possible persistence of increased susceptibility during the puerperium had not been investigated. METHODS: From June 1, 1990, to December 31, 1998, we monitored exposure to malaria, parasitemia, and morbidity among the residents of a village in Senegal in which the rate of transmission of malaria was high. In this population we analyzed 71 pregnancies in 38 women from the year before conception and through one year after delivery. RESULTS: Among the 38 women, there were 58 episodes of clinical Plasmodium falciparum malaria during 61,081 person-days of observation. The incidence of malaria was 20.2 episodes per 1000 person-months during the year preceding conception and 12.0 episodes per 1000 person-months during the period from 91 to 365 days after delivery. The incidence of episodes of malaria increased significantly during the second and third trimesters of pregnancy and reached a maximum of 75.1 episodes per 1000 person-months during the first 60 days after delivery. The adjusted relative risk of an episode of malaria was 4.1 (95 percent confidence interval, 1.8 to 9.5) during the first 60 days post partum, as compared with the year preceding pregnancy. The duration of fever during the episodes of malaria was longer and the prevalence and density of asymptomatic malarial parasitemia were significantly higher during pregnancy and the early postpartum period than during the other periods. CONCLUSIONS: Among women who live in areas with high rates of transmission of malaria, the susceptibility to malaria is highest during the second and third trimesters of pregnancy and the early postpartum period.  相似文献   
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Cancer incidence in Africa is increasing as a result of aging populations, lifestyle changes, and improved detection. However, cancer etiology, prevention, and control in Africa are poorly understood, and survival rates from cancer are among the lowest in the world. Poor cancer survival suggests that improvements in health care, patient education, and relevant research are critically needed. An increase in research infrastructure is required to achieve adequate screening, diagnosis, and treatment of cancer in Africa. While research is a basis for clinical practice and policy changes in resource-abundant areas, the research infrastructure in Africa is deficient in many areas. Building infrastructure for research includes creating supportive environments for research endeavors, securing funding for resources and research personnel, developing training and mentorship opportunities, and building collaborative research with other institutions. Goals for the development of cancer research in Africa may include research on cancer incidence and mortality, cancer etiology and risk factors, clinical research with a focus on early diagnosis/ treatment and palliative care, health economics, and community-based participatory research. An understanding of the environmental and cultural framework by which cancer is diagnosed and managed is critical for developing interventions that will be effective in African populations.  相似文献   
9.
To compare human immunodeficiency virus (HIV) type 1 disease progression in patients infected by the predominant strain circulating recombinant form (CRF) 02_AG in western and west-central Africa and in patients infected by other strains, a prospective multicenter cohort study was conducted in Cameroon and Senegal. Among the 335 patients, a broad HIV-1 group M subtype diversity was observed in the envelope V3-V5 region, but strain CRF02_AG predominated in both Cameroon and Senegal (61.2% and 62.9%, respectively; P<.8). Multivariate analyses showed no difference between patients infected by CRF02 strains and those infected by other strains in terms of survival (adjusted hazards ratio [HR], 1.16; 95% confidence interval [CI], 0.76-1.78; P=.5), clinical disease progression (HR, 0.79; 95% CI, 0.50-1.25; P=.3), or square root CD4 cell decline (regression coefficient, -0.01; 95% CI, -0.82 to 0.81; P=.9). This study suggests that the predominance of HIV-1 CRF02_AG strain in western and west-central Africa should have no major clinical consequences.  相似文献   
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