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991.
Hydroxyurea (HU) is the only drug approved for the induction of fetal hemoglobin. Besides this benefit, there are others such as the reduction of leukocyte and generation of nitric oxide (NO). Sickle cell anemia (SCA) is characterized by chronic hemolytic anemia and vaso-occlusive phenomena. The aim of this study was to evaluate the correlation of parameters MDA and NO2 with the prognosis of patients with SCA as outpatients at Hospital Universitário Walter Cantídeo. In all, 65 patients with SCA--51 without the use of HU (group I) and 14 chronically treated with HU (group II)--were recruited. Nitrite and malonaldehyde were determined by biochemical methods. We found that in group II there was a significant difference of serum MDA with clinical variables: two or more transfusions during the year (P<0.0469), the presence of malleolar ulcers (P<0.0400), and the occurrence of vaso-occlusive episodes (P<0.0031), and Group I with the occurrence of three or more vaso-occlusive episodes (P<0.0051). Correlating the malonaldehyde with clinical variables in groups I and II, we observed a statistically significant relationship with two or more transfusions during the year and the presence of malleolar ulcer. Our results demonstrate that MDA levels can be used as parameter for prognosis in SCA.  相似文献   
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To identify factors that can affect systolic compression of myocardial bridging (MB) of the mid-left anterior descending (LAD) coronary artery with dual-source computed tomography (DSCT). Patients with mid-LAD MB (n = 198) detected by DSCT were studied. MB was classified as incomplete superficial (IS), complete superficial (CS), and deep (D) type. The depth and length of the mid-LAD MB segment in diastole, luminal reduction of the tunneled LAD segment in systole, and degree of systolic left ventricular (LV) wall thickening were all analyzed. Correlation between the depth, length, degree of systolic LV wall thickening, and luminal narrowing in the systolic phase was evaluated. Eighty-one (40.9%) MB were IS, 37 (18.7%) were CS, and 80 (40.4%) were D type. Significant differences in the degree of luminal narrowing in the systolic phase were found among the three MB types (IS, 19.9 ± 10.1%; CS, 26.9 ± 12.1%; D, 36.6 ± 13.8%; P < 0.0001). The luminal narrowing in the systolic phase correlated with the depth (r = 0.56) and percentage of systolic LV wall thickening (r = 0.44), but was not related to length (r = 0.28). In addition to the degree of LV systolic wall thickening and depth of MB, the types of MB also affect luminal narrowing in the systolic phase.  相似文献   
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Type 1 diabetes mellitus (T1DM) is associated with neurocognitive dysfunction and astrogliosis. Physical exercise prevents cognitive impairments and induces important brain modifications. The aim of our study was to investigate the effect of treadmill exercise on spatial memory and astrocytic function in the hippocampus of a T1DM model. Fifty-seven Wistar rats were divided into four groups: trained control (TC) (n = 15), non-trained control (NTC) (n = 13), trained diabetic (TD) (n = 14) and non-trained diabetic (NTD) (n = 15). One month after streptozotocin-induced diabetes, exercise groups were submitted to 5 weeks of physical training, and then, all groups were assessed in the novel object-placement recognition task. Locomotor activity was analyzed in the open field apparatus using Any-maze software. The expression of glial fibrillary acidic protein (GFAP) and S100B in hippocampus and cerebrospinal fluid were measured using ELISA assay, and hippocampal GFAP immunoreactivity was evaluated by means of immunohistochemistry and optical densitometry. The results showed that physical exercise prevents and/or reverts spatial memory impairments observed in NTD animals (P < 0.01). Decreased locomotor activity was observed in both the NTD and TD groups when compared with controls (P < 0.05). ELISA and immunohistochemistry analyzes showed there was a reduction in GFAP levels in the hippocampus of NTD animals, which was not found in TD group. ELISA also showed an increase in S100B levels in the cerebrospinal fluid from the NTD group (P < 0.01) and no such increase was found in the TD group. Our findings indicate that physical exercise prevents and/or reverts the cognitive deficits and astroglial alterations induced by T1DM.  相似文献   
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