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11.
Cytomegalovirus induces T-cell independent apoptosis in brain during immunodeficiency. 总被引:2,自引:0,他引:2
Jon D Reuter 《Journal of clinical virology》2005,32(3):218-223
BACKGROUND: Cytomegalovirus (CMV) is the most common opportunistic viral pathogen associated with HIV/AIDS or immunosuppressive therapy. Systemic pathology may be caused either through direct virus-mediated infection or by indirect mechanisms such as 'by-stander' apoptosis. CMV infection of the central nervous system (CNS) occurs late in disease progression and understanding of pathology in the brain is fundamental for selection of appropriate therapies. OBJECTIVES: Using a model of disseminated neurotropic CMV disease, these experiments are designed to identify cellular predilection of murine CMV (MCMV) within mature brain and to determine, if CMV induces apoptosis within CNS cells. STUDY DESIGN: Adult immunodeficient (SCID) and normal BALB/c mice were infected via the tail vein with 4.5 x 10(5)pfu recombinant MCMV expressing a green fluorescent protein reporter. Animals were perfused at various time periods from 3 to 35 days post inoculation and tissues were stained for MCMV, GFAP, NEU-N, MBP, TUNEL, and caspase-3. RESULTS: CMV infection within brain was observed in multiple, independent foci affecting several different cell types, including neurons, glial cells, meninges, ependymal cells, and cerebral vessels. Cellular changes included nuclear karyopyknosis and karyorrhexis, and associated meningitis, choroiditis, encephalitis, vasculitis, and necrosis. TUNEL and caspase-3 staining of brain-demonstrated apoptosis of nearby 'by-stander' meningial, glial, and neuronal cells, but only in immunodeficient mice lacking T- and B-lymphocytes. Generally, only large CMV infection foci were associated with apoptosis of non-infected adjacent cells. CONCLUSIONS: These results indicate that MCMV may cause both direct and indirect pathology to brain and that T-cell independent apoptosis of surrounding cells of the CNS may be an important mechanism of disease in the pathogenesis of neurotropic CMV. 相似文献
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Diseases like rotavirus afflict both upper- and lower-income countries, but most serious illnesses and deaths occur among the latter. It is a vital public health issue that vaccines for these types of global diseases can recover research and development (R&D) costs from high-priced markets quickly so that manufacturers can offer affordable prices to lower-income nations. Cost recovery depends on how high R&D costs are, and this study attempts to replace high, unverified estimates with lower, more verifiable estimates for two new vaccines, RotaTeq (Merck) and Rotarix (GlaxoSmithKline or GSK), based on detailed searches of public information and follow-up interviews with senior informants. We also offer a new perspective on “cost of capital” as a claim for recovery from public bodies. Our estimates suggest that companies can recover all fixed costs quickly from affluent markets and thus can offer these vaccines to lower-income countries at prices they can afford. Better vaccines are a shared project between companies and public health agencies; greater transparency and consistency in reporting of R&D costs is needed so that fair prices can be established. 相似文献
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Mark Sisco MD ; Jerome D. Chao MD ; Injoong Kim MD ; Jon E. Mogford PhD ; Tanya N. Mayadas PhD ; Thomas A. Mustoe MD 《Wound repair and regeneration》2007,15(4):566-571
The Mac-1 integrin is an important mediator of migration and inflammatory activation of neutrophils and monocytes. However, the role of Mac-1 in modulating macrophage emigration and activation and its subsequent impact on cutaneous wound healing have not been fully elucidated. To examine the significance of Mac-1 to murine wound healing, we measured epithelialization and granulation tissue formation in partial-thickness ear wounds and full-thickness head wounds, respectively, in Mac-1-deficient mice. Wounds were histologically analyzed at postwounding days 3, 5, and 7. The gap measured between the leading edges of inward-migrating granulation tissue was significantly increased in knockout mice compared with control animals at day 5 (3.8+/-0.3 vs. 2.6+/-0.5 mm; p<0.001) and day 7 (2.2+/-0.4 vs. 0.96+/-0.73 mm; p=0.005). Epithelial gap measurements were also increased in knockout mice vs. wild-type controls at days 3 (0.62+/-0.02 vs. 0.54+/-0.07 mm; p<0.05) and 5 (0.58+/-0.06 vs. 0.39+/-0.08 mm; p<0.001). Immunohistochemistry showed equal numbers of macrophages in knockout and control wounds. These findings show that Mac-1 is required for normal wound healing but that the attenuation in the deposition of granulation tissue and wound epithelialization in Mac-1 knockout mice is not associated with decreased monocyte migration into the wound. 相似文献
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Dean McMillan Richard P. Hastings Jon Coldwell 《Journal of Applied Research in Intellectual Disabilities》2004,17(4):255-265
Background There is a high rate of physical violence in populations with intellectual disabilities, and this has been linked to problems for the victim, the assailant, members of staff and services. Despite the clinical significance of this behaviour, few studies have assessed methods of predicting its occurrence. The present study examined clinical and actuarial methods of predicting violence in a forensic intellectual disability hospital. Methods The sample for the study consisted of people resident in the hospital during a 1‐year period (n = 124). Clinical prediction used a risk rating made by members of the person's clinical team, whereas actuarial prediction used the number of violent incidents in the 6‐months before the date of the clinical risk assessment. Computerized hospital records of violence in the 6 months after the assessment were used to examine the predictive accuracy of the two methods. Results The clinical method produced an area under the curve of 0.74 (95% CI: 0.65–0.83) in a receiver–operating characteristic curve analysis. The value for the actuarial method was 0.77 (95% CI: 0.69–0.86). Both methods performed at levels significantly above chance, but no one method was found to be superior to the other. Conclusions These findings suggest that it is possible to predict who is at risk of violence in forensic populations with intellectual disabilities. Here, the authors discuss the clinical implications of these findings and the clinical application of risk prediction within clinical services. 相似文献
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Paclitaxel is an antineoplastic agent derived from the bark of the Pacific yew tree that has activity against many tumors including breast and ovarian carcinomas. In the past, its extravasation quality has been considered to be a local irritant; however, recent reports suggest that the agent may be a vesicant. A patient experienced a delayed vesicant reaction to a paclitaxel extravasation that resulted in severe necrosis. No acute symptoms were reported at the time of extravasation from the 24-hour peripheral paclitaxel infusion. However, on day 11 the patient complained of severe and progressive pain at the site of extravasation. The site was erythematous and had areas of central necrosis requiring debridement and closure by a plastic surgeon. Because paclitaxel possesses vesicant characteristics, health care professionals should be aware of its potential extravasation hazard. Prolonged peripheral infusions should be avoided or administered with extreme caution. 相似文献
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