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11.
Human herpesvirus-8 (HHV-8) causes Kaposi's sarcoma (KS) and lymphoproliferative disorders in both HIV-infected and uninfected patients. HHV-8 has a worldwide occurrence but infection rates vary according to a combination of geographic and behavioral risks. The main transmission route seems to be sexual, nevertheless, nasal secretions, saliva, blood, and organ graft have been proposed. HHV-8 was postulated as a new infectious agent for screening in blood donors. The aim of this study was to evaluate the prevalence of antibodies against HHV-8 antigens in blood donors of South America. Serum samples from 2,470 blood donors from Argentina, Brazil, and Chile corresponding to five geographic regions were studied by indirect immunofluorescence assay (IFA). Seroprevalence rate was 3.7% (92/2,470; 95% CI 2.9-4.5) in the entire blood donor population distributed as follows: Argentina, 4.0% (Buenos Aires city, 4.3%; Bahia Blanca, 2.4%; and Córdoba, 4.0%), Campinas (Brazil), 2.8%; and Santiago de Chile, 3.0%. There was no difference (P>0.05) between men and women or age related, except in Brazil where positive cases were 30-49-year-old males. The present study, which includes different geographical areas of multiple countries from South America, has not been done before. The results show similar prevalence rates among the studied zones corresponding to low-prevalence regions. South America is a large sub-continent with a wide spectrum of population and geographical characteristics, thus, more HHV-8 prevalence studies should be necessary to establish possible regional differences.  相似文献   
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Journal of Prevention - This paper has two goals regarding cultural rigor, defined as privileging cultural ways of knowing and being as a means to achieving health and well-being for future...  相似文献   
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PURPOSE AND EXPERIMENTAL DESIGN: The stem cell factor/KIT receptor loop may represent a novel target for molecular-based therapies of Ewing tumor. We analyzed the in vitro impact of KIT blockade by imatinib in Ewing tumor cell lines. RESULTS: KIT expression was detected in 4 of 4 Ewing tumor cell lines and in 49 of 110 patient samples (44.5%) by immunohistochemistry and/or Western blot analysis. KIT expression was stronger in Ewing tumors showing EWS-FLI1 nontype 1 fusions. Despite absence of c-kit mutations, constitutive and ligand-inducible phosphorylation of KIT was found in all tumor cell lines, indicating an active receptor. Treatment with KIT tyrosine kinase inhibitor imatinib (0.5-20 micro M) induced down-regulation of KIT phosphorylation and dose response inhibition of cell proliferation (IC(50), 12-15 micro M). However, imatinib administered alone at doses close to IC(50) for growth inhibition (10 micro M) did not induce a significant increase in apoptosis. We then analyzed if blockade of KIT loop through imatinib (10 micro M) was able to increase the antitumor in vitro effect of doxorubicin (DXR) and vincristine (VCR), drugs usually used in Ewing tumor treatment. Addition of imatinib decreased in 15-20 and 15-36% of the proliferative rate of Ewing tumor cells exposed to DXR and VCR, respectively, and increased in 15 and 30% of the apoptotic rate of Ewing tumor cells exposed to the same drugs. CONCLUSIONS: Inhibition of Ewing tumor cell proliferation by imatinib is mediated through blockade of KIT receptor signaling. Inhibition of KIT increases sensitivity of these cells to DXR and VCR. This study supports a potential role for imatinib in the treatment of Ewing tumor.  相似文献   
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Dendritic cell leukemia (DCL) or hematodermic tumor is an uncommon subtype of acute leukemia. In contrast to adult cases, children tend to have a less aggressive course. The diagnosis of DCL should be considered when its characteristic morphologic features are present and leukemic cells co‐express CD4 and CD56. Cases of DCL among pediatric patients have been reported to respond to therapeutic regimens for acute lymphoblastic leukemia, but details regarding the specifics of therapy are lacking. Pediatr Blood Cancer 2013; 60: E38–E41. © 2013 Wiley Periodicals, Inc.  相似文献   
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Nephropathy is the most common cause of morbidity and mortality in diabetic patients. Prevention of this complication has a major relevance. Smallanthus sonchifolius (yacon) leaves have been shown to ameliorate hyperglycemia in streptozotocin-induced diabetic rats. We examined the beneficial effects of yacon leaves decoction on diabetic nephropathy and explored the possible underlying action mechanism.  相似文献   
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This article briefly outlines a collaboration among communities on Hawai‘i Island and a university-based research team to develop, implement, and evaluate a school-based substance use prevention curriculum called Ho‘ouna Pono. In addition to providing a rationale for the project, the goal of this paper is fourfold. First, an overview of the Ho‘ouna Pono research results to date (2007–2013) is provided. Second, within this overview, the ways in which selected results informed program development are highlighted. Third, the curriculum is briefly described, and finally, the role of the students and community in the video production is described.  相似文献   
20.
Cellular basis for progesterone neuroprotection in the injured spinal cord   总被引:19,自引:0,他引:19  
Progesterone (PROG) exerts beneficial and neuroprotective effects in the injured central and peripheral nervous system. In the present work, we examine PROG effects on three measures of neuronal function under negative regulation (choline acetyltransferase [ChAT] and Na,K-ATPase) or stimulated (growth-associated protein [GAP-43]) after acute spinal cord transection injury in rats. As expected, spinal cord injury reduced ChAT immunostaining intensity of ventral horn neurons. A 3-day course of intensive PROG treatment of transected rats restored ChAT immunoreactivity, as assessed by frequency histograms that recorded shifts from predominantly light neuronal staining to medium, dark or intense staining typical of control rats. Transection also reduced the expression of the mRNA for the alpha3 catalytic and beta1 regulatory subunits of neuronal Na,K-ATPase, whereas PROG treatment restored both subunit mRNA to normal levels. Additionally, the upregulation observed for GAP-43 mRNA in ventral horn neurons in spinal cord-transected rats, was further enhanced by PROG administration. In no case did PROG modify ChAT immunoreactivity, Na,K-ATPase subunit mRNA or GAP-43 mRNA in control, sham-operated rats. Further, the PROG-mediated effects on these three markers were observed in large, presumably Lamina IX motoneurons, as well as in smaller neurons measuring approximately <500 micro2. Overall, the stimulatory effects of PROG on ChAT appears to replenish acetylcholine, with its stimulatory effects on Na,K-ATPase seems capable of restoring membrane potential, ion transport and nutrient uptake. PROG effects on GAP-43 also appear to accelerate reparative responses to injury. As the cellular basis for PROG neuroprotection becomes better understood it may prove of therapeutic benefit to spinal cord injury patients.  相似文献   
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