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VWF and ADAMTS13 are major determinants of platelet adhesion after vessel injury. In the present study, we aimed to determine whether VWF or ADAMTS13 plasma antigen levels influence the risks of ischemic stroke (IS) or myocardial infarction (MI) in young women and how these risks are affected by oral contraceptive (OC) use. VWF and ADAMTS13 plasma antigen levels were measured in a frequency-matched case-control study of 1018 young (18-49 years) women including 175 IS patients and 205 MI patients. Increasing levels of VWF and decreasing levels of ADAMTS13 were associated with the risk of IS and MI in a dose-dependent manner. Having both high VWF and low ADAMTS13 resulted in an odds ratio (OR) of 6.9 (95% confidence interval [95% CI], 2.0-23.0) for IS and 11.3 (95% CI, 3.6-35.2) for MI. Use of OCs increased the risk of IS and MI associated with high VWF (OR = 12; 95% CI, 5.5-26.2 and OR = 7.5, 95% CI, 3.6-15.7, respectively) and the risk of IS associated with low ADAMTS13 (OR = 5.8, 95% CI, 2.7-12.4). We conclude that high VWF and low ADAMTS13 plasma levels both increase the risk of IS and MI. The risks associated with high VWF or low ADAMTS13 levels are further increased by the use of OCs.  相似文献   
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Strategies that augment a GVL effect without increasing the risk of GVHD are required to improve the outcome after allogeneic stem cell transplantation (SCT). Azacitidine (AZA) up-regulates the expression of tumor Ags on leukemic blasts in vitro and expands the numbers of immunomodulatory T regulatory cells (Tregs) in animal models. Reasoning that AZA might selectively augment a GVL effect, we studied the immunologic sequelae of AZA administration after allogeneic SCT. Twenty-seven patients who had undergone a reduced intensity allogeneic transplantation for acute myeloid leukemia were treated with monthly courses of AZA, and CD8(+) T-cell responses to candidate tumor Ags and circulating Tregs were measured. AZA after transplantation was well tolerated, and its administration was associated with a low incidence of GVHD. Administration of AZA increased the number of Tregs within the first 3 months after transplantation compared with a control population (P = .0127). AZA administration also induced a cytotoxic CD8(+) T-cell response to several tumor Ags, including melanoma-associated Ag 1, B melanoma antigen 1, and Wilm tumor Ag 1. These data support the further examination of AZA after transplantation as a mechanism of augmenting a GVL effect without a concomitant increase in GVHD.  相似文献   
24.
Giant coronary artery aneurysms are rare, with a reported prevalence of 0.02% to 0.2%. Causative factors include atherosclerosis, Takayasu arteritis, congenital disorders, Kawasaki disease, and percutaneous coronary intervention. Most giant coronary artery aneurysms are asymptomatic, but some patients present with angina pectoris, sudden death, fistula formation, pericardial tamponade, compression of surrounding structures, or congestive heart failure. Clinical sequelae include thrombus formation, embolization, fistula formation, and rupture. Surgical correction is generally accepted as the preferred treatment for giant coronary artery aneurysms. We present an illustrative case of a giant 70 × 40-mm coronary artery aneurysm in a 56-year-old man who declined surgery and died one month later. In addition, we provide a review of the medical literature on giant coronary artery aneurysms.  相似文献   
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Under normal conditions the blood circulates freely within the confines of the vascular system, carrying oxygen, nutrients, and hormonal information around the body and removing metabolic waste. If blood gains access to extravascular sites, or the vasculature becomes pathologically challenged, hemostasis may be activated. This process is finely regulated by positive and negative feedback loops that modulate fibrin clot formation. Blood coagulation revolves around the activation and assembly of the components of the prothrombinase complex, which converts the inactive zymogen, prothrombin, into its active form, thrombin. This serine protease catalyzes the conversion of fibrinogen to fibrin, the structural scaffold that stabilizes platelet aggregates at sites of vascular injury. The extent of the hemostatic response is controlled by the action of inhibitory pathways, which ensure that thrombin activity and the spread of the hemostatic plug is limited to the site of vessel damage. This review article focuses on the major physiological regulator of tissue factor-induced coagulation, tissue factor pathway inhibitor, its expression, anticoagulant function, and its role in normal hemostasis.  相似文献   
27.
Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities.  相似文献   
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Galanin is a neuropeptide with multiple inhibitory actions on neurotransmission and memory. In Alzheimer's disease (AD), increased galanin-containing fibers hyperinnervate cholinergic neurons within the basal forebrain in association with a decline in cognition. We generated transgenic mice (GAL-tg) that overexpress galanin under the control of the dopamine beta-hydroxylase promoter to study the neurochemical and behavioral sequelae of a mouse model of galanin overexpression in AD. Overexpression of galanin was associated with a reduction in the number of identifiable neurons producing acetylcholine in the horizontal limb of the diagonal band. Behavioral phenotyping indicated that GAL-tgs displayed normal general health and sensory and motor abilities; however, GAL-tg mice showed selective performance deficits on the Morris spatial navigational task and the social transmission of food preference olfactory memory test. These results suggest that elevated expression of galanin contributes to the neurochemical and cognitive impairments characteristic of AD.  相似文献   
30.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
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