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BAG1 over-expression in brain protects against stroke   总被引:3,自引:0,他引:3  
The co-chaperone BAG1 binds and regulates 70 kDa heat shock proteins (Hsp70/Hsc70) and exhibits cytoprotective activity in cell culture models. Recently, we observed that BAG1 expression is induced during neuronal differentiation in the developing brain. However, the in vivo effects of BAG1 during development and after maturation of the central nervous system have never been examined. We generated transgenic mice over-expressing BAG1 in neurons. While brain development was essentially normal, cultured cortical neurons from transgenic animals exhibited resistance to glutamate-induced, apoptotic neuronal death. Moreover, in an in vivo stroke model involving transient middle cerebral artery occlusion, BAG1 transgenic mice demonstrated decreased mortality and substantially reduced infarct volumes compared to wild-type littermates. Interestingly, brain tissue from BAG1 transgenic mice contained higher levels of neuroprotective Hsp70/Hsc70 protein but not mRNA, suggesting a potential mechanism whereby BAG1 exerts its anti-apoptotic effects. In summary, BAG1 displays potent neuroprotective activity in vivo against stroke, and therefore represents an interesting target for developing new therapeutic strategies including gene therapy and small-molecule drugs for reducing brain injury during cerebral ischemia and neurodegenerative diseases.  相似文献   
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Data on the association between bone microarchitecture and cardiovascular disease (CVD) in men are scarce. We studied the link of bone microarchitecture and areal bone mineral density (aBMD) with the risk of major adverse coronary event (MACE) in a cohort of men aged 60 to 87 years followed prospectively for 8 years. At baseline, aBMD was measured using a Hologic Discovery-A device. Bone microarchitecture was assessed at distal radius and tibia by high-resolution peripheral quantitative computed tomography (XtremeCT Scanco device). During the study, 53 men had incident MACE. The analyses were adjusted for confounders related to bone and CVD. In 813 men (53 MACEs), higher aBMD at the lumbar spine, hip, whole body, and radius was associated with lower risk of MACE (hazard ratio [HR] = 0.44–0.71/SD, p < .025 to < .001). In 745 men having valid distal radius scan (47 MACEs), higher cortical density (Ct.BMD) and higher cortical thickness (Ct.Thd) were associated with lower risk of MACE. This risk was higher in men in the lowest quintile of cortical measures versus the four upper quintiles combined (Ct.BMD: HR = 2.12, 95% confidence interval [CI] 1.08–4.17, p < .025). Findings were similar in 779 men having valid distal tibia scan (48 MACEs). At both sites, higher estimated stiffness and higher failure load were associated with a lower risk of MACE. The risk of MACE was higher in men in the lowest quintile of the measures of bone strength versus four upper quintiles jointly (distal radius stiffness: HR = 2.46, 95% CI 1.27–4.74, p < .01). Similar results were obtained in 638 men without prior fragility fracture and in 689 men without ischemic heart disease at baseline. Thus, in older men followed prospectively for 8 years, higher aBMD, preserved cortical bone status, and higher estimated bone strength were associated with lower risk of MACE after adjustment for relevant confounders. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
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The aim of the present study was to investigate whether amperozide, an antipsychotic drug which possesses anti-aggressive and anxiolytic-like properties, stimulates the secretion of oxytocin and if so, by which receptor mechanism. For this purpose, female or male Sprague Dawley rats were given amperozide (0.5, 2.5 and 5.0 mg/kg IP), ritanserin (5.0 mg/kg), raclopride (2.0 mg/kg) and prazosin (1.0 mg/kg) and were subsequently decapitated for collection of blood (30 and 120 min) after injection. Oxytocin levels were measured with radioimmunoassay. Amperozide 2.5 and 5 mg/kg increased plasma levels of oxytocin significantly (P<0.05 and <0.001). The effect appeared maximal about 30 min after injection of the drug and oxytocin levels were almost back to basal within 120 min. Similar effects were obtained in female and male rats as well as in animals that were freely fed or food deprived for 24 h. CSF levels of oxytocin were also increased. Ritanserin, a 5-HT2-receptor antagonist but not the D2 receptor antagonist raclopride or the 1-adrenoceptor antagonist prazosin stimulated oxytocin release. In addition, clozapine, a neuroleptic with potent HT2-antagonistic properties, was a potent releaser of oxytocin, whereas haloperidol was without effect. A possible role for oxytocin in the behavioural effects of amperozide and clozapine remains to be explored.  相似文献   
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High cytoplasmic expression of maspin was described in ovarian cancers of shorter survival rates. Until now, no relationship has been described between expression of maspin and sensitivity to cisplatin in ovarian cancers. This study aimed at examining the relationship between expression of maspin, detected by immunohistochemistry and clinical response to cisplatin in ovarian cancer cases as well as the in vitro sensitivity to cisplatin of 11 ovarian cancer cell lines. The analyzes were performed on 73 samples of ovarian cancer and on A2780P, A2780RCIS, CAOV-3, EFO 21, EFO 27, ES-2, Mdah 2774, OAW 42, OVCAR-3, PA-1, and SKOV-3 ovarian cancer cells. Cytoplasmic maspin expression in studied cells significantly correlated with cisplatin sensitivity. A significantly shorter overall survival and progression-free survival was associated with lower cytoplasmic maspin expression at first-look laparotomies and nuclear maspin expression and secondary cytoreductions. Higher nuclear maspin at first-look laparotomies expression was specific for cases of complete response. In the study, the elevated expression of maspin was shown to be typical for cisplatin-sensitive ovarian cancers.  相似文献   
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BACKGROUND AND PURPOSE: Calculation of the effective dose and proposal of a dose specification method for the electron beams. PATIENTS AND METHODS: In a homogenous water phantom the 3D dose distributions for electron beams of energy 6, 9, 12, 15, 18 and 21 MeV and beam size 10x10 cm were calculated. For a volume encompassed with 80, 85 and 90% isodose, the mean dose and the SD were calculated for each energy. Using the Brahme's formulae, the effective dose was calculated. RESULTS: The larger the minimum dose (value of the encompassing isodose), the larger the mean dose and the smaller the SD. The mean doses and SD to the volume encompassed with 80, 85 and 90% are in the range of 91-94%, and 5.1-6.2%, 93-96% and 4.2-4.6%, 94-96% and 3.0-3.2%, respectively. Thus the effective dose for the volume encompassed with 80, 85 and 90% are about 90, 93 and 95%, respectively. CONCLUSION: Taking into account the requirements regarding dose uniformity within the PTV and the sparing effect for normal tissue situated under the PTV, we propose to keep the 85% isodose as a minimum one and to prescribe the dose to the 90% isodose. The present method may be applied for single electron beams and typical cases.  相似文献   
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