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Vitamin E consists of tocopherols and tocotrienols, in which α-tocotrienol is the most potent neuroprotective form that is also effective in protecting against stroke in rodents. As neuroprotective agents alone are insufficient to protect against stroke, we sought to test the effects of tocotrienol on the cerebrovascular circulation during ischemic stroke using a preclinical model that enables fluoroscopy-guided angiography. Mongrel canines (mean weight=26.3±3.2 kg) were supplemented with tocotrienol-enriched (TE) supplement (200 mg b.i.d, n=11) or vehicle placebo (n=9) for 10 weeks before inducing transient middle cerebral artery (MCA) occlusion. Magnetic resonance imaging was performed 1 hour and 24 hours post reperfusion to assess stroke-induced lesion volume. Tocotrienol-enriched supplementation significantly attenuated ischemic stroke-induced lesion volume (P<0.005). Furthermore, TE prevented loss of white matter fiber tract connectivity after stroke as evident by probabilistic tractography. Post hoc analysis of cerebral angiograms during MCA occlusion revealed that TE-supplemented canines had improved cerebrovascular collateral circulation to the ischemic MCA territory (P<0.05). Tocotrienol-enriched supplementation induced arteriogenic tissue inhibitor of metalloprotease 1 and subsequently attenuated the activity of matrix metalloproteinase-2. Outcomes of the current preclinical trial set the stage for a clinical trial testing the effects of TE in patients who have suffered from transient ischemic attack and are therefore at a high risk for stroke.  相似文献   
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Introduction

Schizophrenia is associated with a significant risk of suicide, and suicide still remains one of the main causes of death in schizophrenic patients. Beside classic risk factors for suicidality, temperament and character traits have been researched and considered as risk factors for suicidal behavior in recent years.

Method

Subjects were 94 patients with schizophrenia who were under treatment. All patients were in a stable phase of the illness. Patients with lifetime suicide attempt (n = 46) and without suicidal attempt (n = 48) were compared with each other in terms of temperament and character traits by using the Temperament and Character Inventory.

Results

Harm avoidance and persistence scores were higher in suicidal schizophrenic patients compared with nonsuicidal schizophrenic patients. The scores of self-directedness and cooperativeness were lower in suicidal schizophrenic patients compared with nonsuicidal schizophrenic patients. These 4 variables remained significant predictors of lifetime suicidal attempts in a logistic regression model.

Conclusion

To the best of our knowledge, the present study is the first that specifically compares schizophrenic patients with and without suicidal behavior by the Cloninger temperament and character model. Our data indicate that schizophrenic patients will show a greater risk for suicide according to certain personality configurations. However, to establish causal relationships between personality and suicidality in schizophrenia, longitudinal studies are warranted within a multifactorial interactive framework of biologic and clinical variables.  相似文献   
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Exposure to endotoxin has been associated with an exacerbation of asthmatic responses in humans and animal models. However, recent evidence suggests that microbial exposure in early life may protect from the development of asthma and atopy. In this study, we sought to evaluate the effects of lipopolysaccaride (LPS) on airway function in developing mice. In addition, we evaluated the influence of LPS on subsequent allergen sensitization and challenge. Under light anesthesia, 2-3-week-old Balb/c mice received a single intranasal instillation of LPS or sterile physiologic saline. Measurements of airway function were obtained in unrestrained animals, using whole-body plethysmography. Airway responsiveness was expressed in terms of % enhanced pause (Penh) increase from baseline to aerosolized methacholine (Mch). In additional studies, we assessed the functional and cellular responses to ovalbumin sensitization and challenge following prior exposure to LPS.We found that exposure to LPS induced transient airway hyperresponsiveness to Mch. These functional changes were associated with the recruitment of neutrophils and lymphocytes into the bronchoalveolar lavage (BAL) fluid. Airway responsiveness after allergen sensitization and challenge was decreased by prior exposure to LPS. The analysis of BAL cells and cytokines (interferon-gamma and interleukin-4) did not reveal alterations in the overall Th1/Th2 balance.Our findings suggest that LPS leads to airway hyperresponsiveness in developing mice, and may protect against the development of allergen-driven airway dysfunction.  相似文献   
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The authors report a case of alveolar soft-part sarcoma with lung metastases demonstrated by "double imaging" with Tc-99m HDP and Tc-99m MIBI. The tumor originated in the soft tissue with direct invasion to the right scapula, which was hypoactive on bone scan and hyperactive on Tc-99m MIBI images. A focus of dense accumulation of Tc-99m MIBI in the lungs, suggesting metastasis was also demonstrated.  相似文献   
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A seven-year-old boy with neurofibromatosis who developed scalp psoriasis is presented. The clinical evaluation of the patient revealed multiple café au lait spots, axillary freckling, bilateral Lisch nodules and a psoriatic plaque on his scalp. Though there is no known direct relationship between neurofibromatosis and psoriasis, one is suggested in this patient, possibly related to a common genetic defect.  相似文献   
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