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991.
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The learned helplessness (LH) developed after repeat inescapable stress is a well validated animal model of human major depression and is not species specific. c-Fos, the protein product of the protooncogene c-fos, is expressed in neurons under a variety of stressors and could reflect the regional neuronal activation. Using the LH paradigm in mice, we examined c-Fos expression in several brain regions related to stress response or major depression. The LH mice showed significantly lower c-Fos-like immunoreactivity (FLI) in the hippocampus dentate gyrus and the lateral septal nucleus, and higher FLI in the hypothalamic paraventricular nucleus compared with the naive mice. Our finding in the mice LH model supported previous studies in rats showing that the lateral septal nucleus and the hypothalamic paraventricular nucleus are important in LH behaviors. We further demonstrated that hippocampus dentate gyrus, a region important for learning and major depression, may also be involved in the LH behaviors. These related brain regions could provide a basis for further exploration of the molecular mechanisms underlying LH behaviors. 相似文献
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To find out whether close axonal injury resulted in greater free radical risk to cord-projection central neurons than distant ones, we studied the expressions of nitric oxide synthase, calcineurin, and superoxide dismutase in rat rubrospinal neurons following brainstem, C2 and T10 axotomies using immunohistochemical methods. We found that nitric oxide synthase expression was upregulated more following brainstem than C2 lesion while T10 lesion triggered no detectable changes. This response peaked at 1 week and returned to control level by 8-week-post-injury. At the same time, calcineurin, which activated nitric oxide synthase, was increased 1 week following brainstem and C2 axotomies. These suggest that close, but not distant, axotomy enhanced NO production, which appeared to be cytotoxic since blocking NO synthesis with N-nitro-l-arginine methyl ester reduced brainstem axotomy-induced rubrospinal cell loss. On the other hand, the mitochondrial Mn-superoxide dismutase, which competes with NO to prevent the formation of the cytotoxic free radical peroxynitrite, was notably reduced after brainstem but almost unaltered following C2 axotomy. Meanwhile, the cytosolic Cu/Zn-superoxide dismutase was not altered following C2 but increased after brainstem axotomy. Ultrastructurally, in rubrospinal neurons more mitochondria became swollen following brainstem than C2 axotomy. Based on these, we proposed that besides the NO-overproduction-induced toxicity, superoxide-loading-induced mitochondrial damage also added to hampering the survival of the closely axotomized neurons. 相似文献
994.
Association analysis between Tourette's syndrome and dopamine D1 receptor gene in Taiwanese children
OBJECTIVE: Recent research suggests that Tourette's syndrome (TS) may result from a defect in the dopamine system. The dopamine 1 receptor (DRD1) gene is a candidate gene in the study of the etiology of neuropsychiatric diseases that may involve dopaminergic abnormalities. We sought to test the hypothesis that the DRD1 gene might play a role in TS. METHODS: By performing an association study, we collected an independent sample of patients from the midland region of Taiwan and investigated whether DRD1 gene polymorphisms can be used as markers of susceptibility to TS. A total of 148 children with TS and 83 normal control subjects were included in the study. A polymerase chain reaction was used to identify the A/G polymorphism of the DRD1 gene. Genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were compared. RESULTS: The results showed that genotypes and allelic frequencies for the DRD1 gene polymorphisms in both groups were not significantly different. CONCLUSION: These data suggest that DRD1 gene may not be a useful marker for prediction of the susceptibility of TS. 相似文献
995.
Aspiration has been frequently noted among patients suffering from vocal-fold paralysis. The association between a defect of glottal closure and aspiration in patients with unilateral vocal paralysis appears to have been rarely reported. The current study reviews collected data consisting of videotaped flexible nasoendoscopy and stroboscopy for patients with a unilateral vocal-fold paralysis. Mean normalized glottal gap areas for patients suffering vocal paralysis with associated aspiration are significant greater than that for the non-aspiration group. Subsequent to the surgical correction of the glottal gap, all patients recovered well from their earlier aspiration. The investigation of objectively derived data revealed that poor airway protection due to incomplete closure of the vocal fold was the major cause of aspiration for patients suffering unilateral vocal-fold paralysis. Intracordal autologous fat injection can successfully improve the breath control and eliminate aspiration in patients with vocal-fold paralysis. 相似文献
996.
Sclerosant extravasation as a complication of sclerosing endotherapy for bleeding gastric varices 总被引:1,自引:0,他引:1
We report here the case of a 65-year-old woman who suffered intraperitoneal sclerosant leakage after endoscopic injection sclerotherapy for bleeding gastric varices. In total, 3 ml of N-butyl-2-cyanoacrylate and Lipiodol mixture was injected. The patient developed mild fever and pain over the left upper quadrant and flank after the procedure. In addition to a Lipiodol-filled gastric varix, the imaging studies disclosed a wide spread of Lipiodol over the left peritoneal cavity. The patient was kept fasting with parenteral antibiotics and nutrition. She responded well to the treatment, and all of the symptoms had subsided 6 days later. 相似文献
997.
Issues in the design of a clinical trial with a behavioral intervention--the Zambia exclusive breast-feeding study 总被引:1,自引:0,他引:1
Thea DM Vwalika C Kasonde P Kankasa C Sinkala M Semrau K Shutes E Ayash C Tsai WY Aldrovandi G Kuhn L 《Controlled clinical trials》2004,25(4):353-365
PURPOSE: We present the rationale and design of the Zambian Exclusive Breast-feeding Study (ZEBS), a randomized trial evaluating the efficacy of short-duration exclusive breast-feeding (EBF) as a strategy to reduce postnatal human immunodeficiency virus (HIV) transmission while preserving the other health benefits of this important mode of infant feeding. METHODS: One thousand two hundred HIV-positive pregnant women were recruited in Lusaka, Zambia, and followed with their infants for 24 months. In addition to Nevirapine (NVP), all women received intensive and frequent clinic- and home-based counseling to support exclusive breast-feeding. When the infant was 1 week of age, half of the women were randomly assigned to a group encouraged to abruptly (<24 h) cease all breast-feeding at 4 months. The primary outcome of the experimental (randomized) comparison is HIV-free survival at 24 months. The design is also observational and will compare HIV transmission rates between those who do and do not adhere to the counseling intervention promoting exclusive breast-feeding. CONCLUSION: Our study aims to quantify the benefit-risk ratio of early cessation of exclusive breast-feeding to interrupt mother-to-child transmission of HIV with an intensive behavioral intervention and has both observational and experimental analytic approaches. Our study design assesses efficacy and also has a prominent applied component that if the intervention is effective, it will permit rapid and sustainable adoption within low-resource communities. 相似文献
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