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Patrick J. Blair Lawrence H. Boise Stephen P. Perfetto Bruce L. Levine Gil McCrary Kenneth F. Wagner Daniel C. St. Louis Craig B. Thompson Jeffrey N. Siegel Carl H. June 《Journal of clinical immunology》1997,17(3):234-246
Progression to AIDS in asymptomatic HIV-infected individuals is characterized by a gradual but progressive loss of CD4+ T cells. While the mechanisms underlying this decline are currently unknown, recent evidence suggests that these cells are abnormally sensitive to apoptosis in response to activation signals. Recent work has implicated downregulation of Bcl-2 with the increased spontaneous apoptosis in lymphocytes from HIV-infected patients. We have evaluated the roles of the apoptosis-protective proteins Bcl-2 and Bcl-x in stimulated PBMC from asymptomatic HIV-infected and HIV-uninfected individuals. We found that Bcl-2 was constitutively expressed in PBMC from both HIV-infected and uninfected samples. However, Bcl-x induction was delayed and responses were decreased in stimulated HIV-infected samples. Additionally, single-cell intracellular staining of Bcl-x revealed a significant inverse correlation between PWM-induced Bcl-x expression and apoptosis (r = –0.695, P = 0.005). This was confirmed at the single-cell level in direct experiments when stimulated cells were sorted based on Bcl-x induction and then measured for apoptosis. Furthermore, low Bcl-x expression was not due to reduced lymphocyte activation following PWM stimulation. Our data indicate that the induction of Bcl-x is markedly impaired in asymptomatic HIV-infected patients and that stimuli which induce inadequate expression of Bcl-x are associated with increased levels of apoptosis in these cells. 相似文献
224.
S Kanowski P K Fischhof R Grobe-Einsler G Wagner G Litschauer 《Pharmacopsychiatry》1990,23(3):118-124
Activation of cerebral metabolism and improvement of microcirculation by influencing rheological parameters are claimed to be the underlying pharmacological principles responsible for the efficacy of xantinolnicotinate. This dual mechanism of action led the authors to perform a double-blind, randomized, placebo-controlled study in patients with mild to moderate dementia (DSM III), characterized by a score of 40-90 on the Sandoz Clinical Geriatric Scale (SCAG), with a separate randomization for patients with Multi-Infarct Dementia (MID) and Senile Dementia of Alzheimer Type (SDAT). It was calculated that 150 patients would have to be recruited for each group. Allocation to the respective group (MID or SDAT) was based on the Hachinski Ischemic Score and computer tomogram. Preceded by a 2-week placebo run-in period, a 12-week treatment period followed with either 3 x 1 g xantinolnicotinate (Complamin) or placebo. Prior to the study, the physician's rating of the global therapeutic effect from the clinical global impression (CGI) was designated as the primary criterion of efficacy. Secondary efficacy criteria were SCAG, the BGP nursing rating, and, as psychometric variables, tests from the Nuremberg Psychogeriatric Inventory (NAI). The improvement compared to placebo was statistically significant for the CGI in both treatment groups (p less than 0.0001) and hence independent of etiology. Concerning the nurses' rating (BGP), apart from a marginally statistically significant difference for the factor "need of help" in the SDAT group, no remarkable changes were registered during treatment. However, in the SCAG the differences between verum and placebo were significant (MID p less than 0.0002; SDAT p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
225.
N B Webb G A Sakheim L Towns-Miranda C R Wagner 《The American journal of orthopsychiatry》1990,60(2):305-310
Assessment, preventive intervention, and interdisciplinary collaboration between the fire department and mental health services are highlighted as key factors in the identification and treatment of juvenile firesetters and their families. An interagency pilot program in New York City is described and the importance of "aggressive" outreach is emphasized. 相似文献
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