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101.
Modification of gamma radiation induced response of peritoneal macrophages and splenocytes by Hippophae rhamnoides (RH-3) in mice 总被引:2,自引:0,他引:2
Alcoholic extract of Hippophae rhamnoides, RH-3, reported to render >80% survival against lethal whole body Co-60-gamma irradiation (10 Gy) in mice, was investigated for its immunostimulatory effects. In comparison with un-irradiated control, whole body irradiation did not reduce peritoneal macrophage counts at 24 h post-irradiation. RH-3 treatment (30 mg kg(-1) body weight) alone or 30 min before whole-body irradiation enhanced viable counts of macrophages significantly (P< or =0.05) compared with both un-irradiated control and irradiated groups. Whole-body irradiation reduced the number of viable splenocytes significantly (P<0.05) compared with un-irradiated control at 24 h post-irradiation. RH-3 treatment alone or before whole-body irradiation appreciably countered radiation-induced decrease in splenocyte count. 3H-thymidine uptake method revealed that whole-body irradiation reduced splenocyte proliferation significantly (159 +/- 45 counts min(-1)/10(6) cells; P< or =0.05) in comparison with control (607 +/- 142 counts min(-1)) at 24 h after irradiation but RH3 treatment before irradiation reduced the steep decrease and maintained it as 444+/-153 counts min(-1). After whole-body irradiation, the ratio of spleen weight/mouse weight decreased to 1.5 +/- 04 compared with 2.9 +/- 0.32 in un-irradiated control at 24 h post-irradiation. Similarly, total protein content in splenocytes also decreased to 48 +/- 6 microg/10(6) cells in comparison with 368 +/- 16 microg/10(6) cells of un-irradiated control. RH-3 treatment before irradiation countered radiation-induced decrease in both spleen weight/mouse weight ratio (4.0 +/- 0.35) and total protein content (360 +/- 13 mug/10(6) splenocytes). In the supernatant of peritoneal macrophage cultures exposed to 2 Gy Co-60-gamma radiation ex-vivo, the total nitrite content was enhanced significantly (P<0.05) to 5.72 +/- 0.09 microM in comparison with un-irradiated control (1.64 +/- 0.09 microM). RH-3 treatment (30 microg mL(-1)) before irradiation reduced total nitrite significantly (0.93 +/- 0.3; P< or =0.05) in comparison with irradiated control group. At 24 h after whole body irradiation, the CD4+/CD8+ ratio reduced to 1.5 in comparison with un-irradiated control (1.9) but RH-3 treatment before irradiation restored the ratio to 2.1. These findings explicitly reveal the immunostimulatory activity of RH-3, which may play an important role in the manifestation of its radioprotective efficacy. 相似文献
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André?C.?LapeyreEmail author Indu?G.?Poornima Todd?D.?Miller David?O.?Hodge Timothy?F.?Christian Raymond?J.?Gibbons 《Journal of nuclear cardiology》2005,12(1):37-42
BACKGROUND: The aim of this study is to assess the prognostic value of pharmacologic stress (adenosine or dipyridamole) myocardial perfusion imaging in patients with permanent electronic ventricular pacemakers. METHODS AND RESULTS: Between October 1986 and December 1995, 93 patients with pacemakers underwent pharmacologic stress testing with myocardial perfusion single photon emission computed tomography imaging. Follow-up information on 91 patients (98%) was obtained. Mean follow-up was 5.6 +/- 2.4 years. Previously published clinical and image variables were analyzed for their prognostic significance with regard to cardiac death, cardiac death/nonfatal myocardial infarction, and cardiac death/nonfatal myocardial infarction/late revascularization. The presence of a high-risk scan was a significant predictor of subsequent cardiac death by both univariate (chi 2 = 9.4, P < .001) and multivariate analysis (chi 2 = 6.5, P = .01) after adjustment for clinical score. Clinical score was not a significant predictor of cardiac death. CONCLUSION: This study demonstrates that pharmacologic stress myocardial perfusion imaging provides significant prognostic information in patients with permanent pacemakers. In this population, pharmacologic stress myocardial perfusion imaging can differentiate patients at high risk of a subsequent cardiac event from those at low risk. These results support the American College of Cardiology/American Heart Association guideline recommendations for pharmacologic stress perfusion imaging in patients with permanent pacemakers. 相似文献
104.
Multicomponent antituberculous subunit vaccine based on immunodominant antigens of Mycobacterium tuberculosis 总被引:1,自引:0,他引:1
The low molecular mass polypeptides of secretory proteome of Mycobacterium tuberculosis are dominant targets for recognition by lymphocytes of human models of immunity to tuberculosis. In the present study, we evaluated the inherent immunogenicity of 102 individual polypeptides purified from low molecular mass region below 40kDa in mouse model of immunization. The aim of this study was to identify molecules relevant for development of subunit vaccine against tuberculosis based on high degree of immunogenecity. Here, we demonstrate that experimental multicomponent subunit vaccine (MSV) consisting of five immunodominant polypeptides with high immunogenicity (CFP-25, CFP-20.5, Ag85B, Ag85A and CPF-32) induced both cellular and humoral immune responses characterized by Th1 and Th2 cytokine induction and imparted significant protection when administered with DDA-MPL adjuvants in C57BL/6J mice. The degree of protection imparted by experimental MSV on the basis of decrease in CFU's from target organs (lungs and spleen) was comparable to BCG and total mycobacterial culture filtrate proteins (CFPs) based vaccines. These results, therefore, suggest the potential of multicomponent subunit vaccination against tuberculosis based on strongly immunogenic proteins of M. tuberculosis. 相似文献
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Manyam BV 《Parkinsonism & related disorders》2005,11(2):73-80
Bilateral almost symmetric calcification involving striatum, pallidum with or without deposits in dentate nucleus, thalamus and white matter is reported from asymptomatic individuals to a variety of neurological conditions including autosomal dominant inheritance to pseudo-pseudohypoparathyroidism. While bilateral striopallidodentate calcinosis is commonly referred to as 'Fahr's disease' (a misnomer), there are 35 additional names used in the literature for the same condition. Secondary bilateral calcification is also reported in a variety of genetic, developmental, metabolic, infectious and other conditions. In autosomal dominant or sporadic bilateral striopallidodentate calcinosis no known calcium metabolism abnormalities are known to date. Clinically, parkinsonism or other movement disorders appear to be the most common presentation, followed by cognitive impairment and ataxia. When presence of movement disorder, cognitive impairment and ataxia are present, a computed tomography scan of the head should be considered to rule-in or rule-out calcium deposits. Calcium and other mineral deposits cannot be linked to a single chromosomal locus. Further genetic studies to identify the chromosomal locus for the disease are in progress. 相似文献
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OBJECTIVE: To examine the prevalence of mental and physical distress indicators among women of reproductive age and the association of these indicators with cigarette smoking and alcohol use, by pregnancy status. METHODS: The Behavioral Risk Factor Surveillance System data for several years were aggregated across states and weighted for this analysis. Seven measures of self-reported mental and physical distress and general health were examined along with demographic variables. RESULTS: Overall, 6.7% (95% confidence interval [CI] 6.5-6.9) of women reported frequent physical distress, 12.3% (95% CI 12.0-12.6) reported frequent mental distress, 9.9% (95% CI 9.4-10.4) reported frequent depression, 18.4% (95% CI 17.8-19.1) reported feeling anxious, and 34.3% (95% CI 33.5-35.1) reported that they frequently did not get enough rest. At the time of the survey 4.6% of the women were pregnant. Pregnant women were less likely than nonpregnant women to report frequent mental distress. Although there was attenuation of cigarette smoking and alcohol use during pregnancy, those with mental and physical distress were more likely to consume cigarettes and alcohol than were those without such experiences. CONCLUSION: High proportions of reproductive-age women report frequent mental and physical distress. Women experiencing mental and physical distress were more likely to report consuming cigarettes and alcohol than women without such experiences. 相似文献