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91.
To assess the neuroendocrine correlates of menstrual status migrainosus (MSM) and menstrual migraine (MM), we evaluated the prolactin (PRL) and cortisol responses to the direct central serotoninergic (5-HT) agonist meta-chlorophenylpiperazine (m-CPP) administered orally (0.5 mg/kg) during the follicular (FP: +6, +8) and luteal phases (LP: -4, -6) of the same menstrual cycle. Ten women with MSM (migraine attacks occurring within 2 days of the onset of menstrual bleeding but lasting more than 72 h) and 9 women with MM (migraine occurring within 2 days of the onset of menstrual bleeding with a typical duration of attacks) were studied. Six healthy women served as controls. Blood samples were taken at times -30, 0 and every 30 min over 4 h. Statistical analysis was performed using MANOVA followed by Duncan's post hoc comparisons. We found that the PRL response to the m-CPP test was significantly blunted in MSM compared with MM and controls in both phases of the menstrual cycle (F = 4.6; p < 0.001). Indeed, the PRL area under the curve (AUC) after m-CPP was higher in both MM and controls compared with MSM (F = 12.7; p < 0.001). The m-CPP-induced cortisol response was absent in MSM compared with MM and controls in both FP and LP (F = 4.1; p < 0.001). On the other hand, the pattern of the plasma cortisol response to m-CPP was similar in MM and controls throughout the menstrual cycle. In addition, the basal plasma cortisol levels were significantly higher in MSM compared with controls (p < 0.001) and MM (p < 0.001) during FP, but not in LP, and progressively decreased over time. Thus, no significant effect of the menstrual cycle phase and diagnosis on the cortisol AUC was found, while a significant diagnosis effect (F = 25.6; p < 0.001) on %delta(max) plasma cortisol levels was evident and consistent with the lack of cortisol response to m-CPP in MSM during the FP and LP compared with MM and controls. A derangement in central 5-HT control of pituitary PRL, and even more so in cortisol release, is present in women with MSM, but not with MM, regardless of the phase of the menstrual cycle, suggesting the involvement of some 5-HT(1) and 5-HT(2) receptor subtypes in the occurrence of extremely severe migraine attacks triggered by menstruation.  相似文献   
92.
3-Hydroxypropyl flufenamide (Flu-HPA) is one of a series of flufenamic acid derivatives that enhances blood clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The profibrinolytic activity of Flu-HPA in clot lysis assays was found to be dependent on plasminogen. The influence of Flu-HPA on the ability of purified alpha 2-antiplasmin to inhibit purified plasmin was studied. Plasmin activity was determined using 125I-fibrin plates or the spectrophotometric tripeptide substrate, Val-Leu-Lys-paranitroanilide. At Flu-HPA concentrations greater than 1 mM, the inhibitory activity of alpha 2-antiplasmin was abolished in a time-dependent and concentration- dependent manner. The influence of Flu-HPA on the ability of purified Cl inhibitor to inhibit purified plasma kallikrein and beta-Factor XIIa was also studied. Cl inhibitor activity was abolished by Flu-HPA at concentrations greater than 2 mM. Notably, Flu-HPA up to 60 mM did not affect the amidolytic activities of plasmin, kallikrein, or beta-Factor XIIa. Flu-HPA did not release enzyme activity from preformed complexes of either alpha 2-antiplasmin and plasmin of Cl inhibitor and kallikrein. A water-soluble derivative of flufenamic acid, N-flufenamyl- glutamic acid, also inactivated alpha 2-antiplasm and Cl inhibitor. This inactivation was shown to be reversible. These results indicate that synthetic fibrinolytic compounds such as flufenamic acid derivatives may promote fibrinolysis by directly inactivating alpha 2- antiplasmin and Cl inhibitor.  相似文献   
93.
European Journal of Nuclear Medicine and Molecular Imaging - Cardiac imaging with positron emission tomography/computed tomography (PET/CT) allows measurement of coronary artery calcium (CAC),...  相似文献   
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The detection and quantitation of apoptotic cells is becoming increasingly important in the investigation of the role of apoptosis in cellular proliferation and differentiation. The pathogenesis of hematologic disorders such as aplastic anemia and the development of neoplasia are believed to involve dysregulation of apoptosis. To quantitate accurately the proportion of apoptosis cells within different cell types of a heterogeneous cell population such as blood or bone marrow, a method is required that combines the analysis of large numbers of cells with concurrent immunophenotyping of cell surface antigens. In this study, we have evaluated such a method using the fluorescent DNA binding agent, 7-amino actinomycin D (7AAD), to stain three diverse human cell lines, induced to undergo apoptosis by three different stimuli. Flow cytometric analysis defines three populations on the basis of 7AAD fluorescence and forward light scatter. We have shown by cell sorting and subsequent morphological assessment and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling that the populations defined by 7AAD represent live, apoptotic, and late-apoptotic/dead cells. This method is quick, simple, reproducible, and cheap and will be a valuable tool in the investigation of the role of apoptosis in normal physiology and in disease states.  相似文献   
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目的 探讨整合素在体外培养的椎间盘细胞力学传导中的作用。方法采用猪的椎间盘进行体外细胞的分离和培养,对细胞施加周期性液压负荷,通过对细胞的形态学观察、Western免疫印迹、免疫细胞化学染色和免疫荧光,分别检测整合素α3和肌动蛋白在周期性压力下椎间盘细胞中的表达。结果经加压后,纤维环细胞和髓核细胞均可见体积缩小,由多角形转变为细长形,α3和肌动蛋白在AF和NP细胞中的表达均明显减少。结论压力抑制了整合素α3的产生,整合素α3将力的信号转换到细胞内时,进一步影响到与其关系密切的肌动蛋白。  相似文献   
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Objective.— In this study, we evaluated the influence of sex and estrogen treatment on nitroglycerin (NTG)‐induced neuronal activation in the rat brain. Background.— Systemic NTG activates cerebral nuclei of rat involved in nociceptive transmission, as well as in neuroendocrine and autonomic functions. These changes are considered relevant for migraine, since NTG consistently induces spontaneous‐like attacks in migraineurs. Methods.— Intact and castrated male and female rats, and castrated female rats treated with estradiol benzoate (or placebo) were injected with NTG and sacrificed after 4 hours. Rats were perfused, and their brains were processed for Fos protein, a marker of neuronal activation. Results.— Data showed a reduced expression of NTG‐induced Fos protein in the paraventricular nucleus (PVH), supraoptic nucleus (SON), and nucleus trigeminalis caudalis (SPVC) of male rats in comparison with female rats. Furthermore, in castrated female rats, NTG‐induced neuronal activation was reduced in PVH, SON, central nucleus of the amygdala (AMI), nucleus tractus solitarius (NTS), area postrema (AP), and SPVC, while in castrated male rats Fos expression was reduced uniquely in the SPVC. Chronic administration of estrogens restored Fos protein expression in PVH, SON, AMI, NTS, AP, and SPVC in castrated female rats. Conclusion.— These data provide a support for the existence of a sexual dimorphism in NTG‐induced neuronal activation, and they prompt a specific model for evaluating and modulating the influence of estrogens upon the cerebral structures implicated in the pathophysiology of migraine.  相似文献   
100.
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