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Platelet release by megakaryocytes is regulated by a concert of environmental and autocrine factors. We previously showed that constitutively released adenosine diphosphate by human megakaryocytes leads to platelet production. Here we show that adenosine diphosphate elicits, in human megakaryocytes, an increase in cytosolic calcium concentration, followed by a plateau, which is lowered in the absence of extracellular calcium, suggesting the involvement of Store-Operated Calcium Entry. Indeed, we demonstrate that megakaryocytes express the major candidates to mediate Store-Operated Calcium Entry, stromal interaction molecule 1, Orai1 and canonical transient receptor potential 1, which are activated upon either pharmacological or physiological depletion of the intracellular calcium pool. This mechanism is inhibited by phospholipase C or inositol-3-phosphate receptor inhibitors and by a specific calcium entry blocker. Studies on megakaryocyte behavior, on extracellular matrix proteins that support proplatelet extension, show that calcium mobilization from intracellular stores activates signaling cascades that trigger megakaryocyte adhesion and proplatelet formation, and promotes extracellular calcium entry which is primarily involved in the regulation of the contractile force responsible for megakaryocyte motility. These findings provide the first evidence that both calcium mobilization from intracellular stores and extracellular calcium entry specifically regulate human megakaryocyte functions.  相似文献   
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Irritable bowel syndrome(IBS)is regarded as a multifactorial disease in which alterations in the brain-gut axis signaling play a major role.The biopsychosocial model applied to the understanding of IBS pathophysiology assumes that psychosocial factors,interacting with peripheral/central neuroendocrine and immune changes,may induce symptoms of IBS,modulate symptom severity,influence illness experience and quality of life,and affect outcome.The present review focuses on the role of negative affects,including depression,anxiety,and anger,on pathogenesis and clinical expression of IBS.The potential role of the autonomic nervous system,stress-hormone system,and immune system in the pathophysiology of both negative affects and IBS are taken into account.Psychiatric comorbidity and subclinical variations in levels of depression,anxiety,and anger are further discussed in relation to the main pathophysiological and symptomatic correlates of IBS,such as sensorimotor functions,gut microbiota,inflammation/immunity,and symptom reporting.  相似文献   
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Autoimmunology is a super-specialty of immunology specifically dealing with autoimmune disorders. To assess the extant literature concerning autoimmune disorders, bibliometric and scientometric analyses (namely, research topics/keywords co-occurrence, journal co-citation, citations, and scientific output trends – both crude and normalized, authors network, leading authors, countries, and organizations analysis) were carried out using open-source software, namely, VOSviewer and SciCurve. A corpus of 169,519 articles containing the keyword “autoimmunity” was utilized, selecting PubMed/MEDLINE as bibliographic thesaurus. Journals specifically devoted to autoimmune disorders were six and covered approximately 4.15% of the entire scientific production. Compared with all the corpus (from 1946 on), these specialized journals have been established relatively few decades ago. Top countries were the United States, Japan, Germany, United Kingdom, Italy, China, France, Canada, Australia, and Israel. Trending topics are represented by the role of microRNAs (miRNAs) in the ethiopathogenesis of autoimmune disorders, contributions of genetics and of epigenetic modifications, role of vitamins, management during pregnancy and the impact of gender. New subsets of immune cells have been extensively investigated, with a focus on interleukin production and release and on Th17 cells. Autoimmunology is emerging as a new discipline within immunology, with its own bibliometric properties, an identified scientific community and specifically devoted journals.  相似文献   
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目的:分析Rho激酶抑制剂治疗短暂性脑缺血发作的效果。方法将172例短暂性脑缺血发作患者分为两组,对照组给予常规治疗,治疗组给予法舒地尔注射液治疗。结果治疗组治疗总有效率高于对照组,不良反应轻微不影响治疗。结论 Rho激酶抑制剂治疗短暂性脑缺血发作效果显著。  相似文献   
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