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41.
AIM: To study the antitumor effect and antioxidant role of Bauhinia racemosa. METHODS: Antitumor activity and antioxidant status of methanol extract (50, 100, and 200 mg/kg) of Bauhinia racemosa stem bark was evaluated against Ehrlich ascites carcinoma (EAC) tumor in mice. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of methanol extract of Bauhinia racemosa (MEBR). After 24 h of tumor inoculation, the extract was administered daily for 14 d. After administration of the last dose followed by 18 h fasting, mice were then sacrificed for observation of antitumor activity. The effect of MEBR on the growth of transplantable murine tumor, life span of EAC bearing hosts and simultaneous alterations in the hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. RESULTS: The MEBR showed decrease in tumor volume, packed cell volume and viable cell count, and increased the nonviable cell count and mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to more or less normal levels in extract treated mice. Treatment with MEBR decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. CONCLUSION: The methanol extract of Bauhinia racemosa stem bark exhibited antitumor effect by modulating lipid peroxidation and augmenting antioxidant defense system in EAC bearing mice.  相似文献   
42.
This case-control study adds to the growing body of knowledge on the medical, nutritional, and environmental factors associated with Nodding Syndrome (NS), a seizure disorder of children and adolescents in northern Uganda. Past research described a significant association between NS and prior history of measles infection, dependence on emergency food and, at head nodding onset, subsistence on moldy maize, which has the potential to harbor mycotoxins. We used LC-MS/MS to screen for current mycotoxin loads by evaluating nine analytes in urine samples from age-and-gender matched NS cases (n = 50) and Community Controls (CC, n = 50). The presence of the three mycotoxins identified in the screening was not significantly different between the two groups, so samples were combined to generate an overall view of exposure in this community during the study. Compared against subsequently run standards, α-zearalenol (43 ± 103 µg/L in 15 samples > limit of quantitation (LOQ); 0 (0/359) µg/L), T-2 toxin (39 ± 81 µg/L in 72 samples > LOQ; 0 (0/425) µg/L) and aflatoxin M1 (4 ± 10 µg/L in 15 samples > LOQ; 0 (0/45) µg/L) were detected and calculated as the average concentration ± SD; median (min/max). Ninety-five percent of the samples had at least one urinary mycotoxin; 87% were positive for two of the three compounds detected. While mycotoxin loads at NS onset years ago are and will remain unknown, this study showed that children with and without NS currently harbor foodborne mycotoxins, including those associated with maize.  相似文献   
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Agah  R; Charak  BS; Chen  V; Mazumder  A 《Blood》1991,78(3):720-727
This work is a continuation of our studies that showed that interleukin- 2 (IL-2)-activated murine bone marrow (ABM) cells have potent cytotoxic potential against murine cytomegalovirus (MCMV)-infected targets in vitro, without loss of reconstitutive ability in vivo. Our data show that ABM cells lyse the MCMV-infected cells in vitro, at both acute and chronic stages of infection; this lysis is specific for the MCMV- infected cells. ABM cells supplemented with IL-2 therapy virtually eradicated the viral infection and prolonged the survival of MCMV- infected Balb/c mice, whether or not they were immunocompromised by irradiation (P less than .001 in both situations). Efficacy of ABM cells alone or IL-2 alone was less than the combination of ABM cells and IL-2. The efficacy of combination treatment with ABM cells and IL-2 in improving the survival of MCMV-infected mice was comparable, whether used in a preventive or a therapeutic setting. Therapy with ABM plus IL- 2 also prevented the reactivation of chronic MCMV infection after irradiation. Preliminary findings indicate that Thy-1+ and asialo GM1+ cells limited the MCMV proliferation by approximately 30% and 80%, respectively, while BM macrophages limited the proliferation of MCMV by 100%. These results suggest that BM transplantation (BMT) with ABM cells followed by IL-2 therapy may constitute a novel strategy to improve the host resistance against cytomegalovirus infection after BMT.  相似文献   
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