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81.
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83.
ObjectivesRegular physical exercise is known to protect endothelial integrity. It has been proposed that acute exercise-induced changes of the (anti-)oxidative system influence early (glycocalyx shedding) and sustained endothelial activation (shedding of endothelial cells, ECs) as well as endothelial-cell repair by circulating hematopoietic stem and progenitor cells (HPCs). However, results are not conclusive and data in trained participants performing different exercise modalities is lacking.DesignEighteen healthy, well-trained participants (9 runners, 9 cyclists; age: 29.7 ± 4.2 yrs) performed a strenuous acute exercise session consisting of 4 bouts of 4-min high-intensity with decreasing power profile and 3-min low-intensity in-between.MethodsAverage power/speed of intense phases was 85% of the peak achieved in a previous incremental test. Before and shortly after exercise, total oxidative and antioxidative capacities (TAC), shedding of syndecan-1, heparan sulfate, hyaluronan, ECs, and circulating HPCs were investigated.ResultsTAC decreased from 1.81 ± 0.42 nmol/L to 1.47 ± 0.23 nmol/L post-exercise (p = 0.010) only in runners. Exercise-induced early and sustained endothelial activation were enhanced post-exercise- syndecan-1: 103.2 ± 63.3 ng/mL to 111.3 ± 71.3 ng/mL, heparan sulfate: from 2637.9 ± 800.1 ng/mL to 3197.1 ± 1416.3 ng/mL, both p < 0.05; hyaluronan: 84.3 ± 21.8 ng/mL to 121.4 ± 29.4 ng/mL, ECs: from 6.6 ± 4.5 cells/μL to 9.5 ± 6.2 cells/μL, both p < 0.01; results were not different between exercise modalities and negatively related to TAC concentrations post-exercise. HPC proportions and self-renewal ability were negatively, while EC concentrations were positively associated with circulating hyaluronan concentrations.ConclusionsThese results highlight the importance of the antioxidative system to prevent the endothelium from acute exercise-induced vascular injury – independent of exercise modality – in well-trained participants. Endothelial-cell repair is associated with hyluronan signaling, possibly a similar mechanism as in wound repair.  相似文献   
84.
Although the inherent complexity of the multifactorial nature of primary Sjögren's syndrome (pSS) renders the process of disease prognostication and prediction ambiguous, certain clinical and immunological characteristics have been described as lymphoma predictors in several studies. While the association between pSS and mucosa-associated lymphoid tissue lymphomas is indisputable, recent studies report a predominance of diffuse large B-cell lymphomas implying that pSS-lymphoma association is less subtype-specific than previously considered. The considerable differences in both disease severity and prognosis between patients with various types of lymphoma demand the identification of risk factors that can predict the development of the distinct subtypes. Additionally, a recently discovered diverse range of biological variables appears to influence clinical behavior and lymphoma outcome. In this review, we venture into the area of lymphoma prognostication in pSS, outlining long-established predictors, analyzing currently available prognostic models, and exploring the predictive potential of recent biological and molecular advances.  相似文献   
85.
Gypenosides (GPs) have been reported to have neuroprotective effects in addition to other bioactivities. The protective activity of GPs during stroke and their effects on neural stem cells (NSCs) in the ischemic brain have not been fully elucidated. Here, we test the effects of GPs during stroke and on the NSCs within the subventricular zone (SVZ) of middle cerebral artery occlusion (MCAO) rats. Our results show that pre-treatment with GPs can reduce infarct volume and improve motor function following MCAO. Pre-treatment with GPs significantly increased the number of BrdU-positive cells in the ipsilateral and contralateral SVZ of MCAO rats. The proliferating cells in both sides of the SVZ were glial fibrillary acidic protein (GFAP)/nestin-positive type B cells and doublecortin (DCX)/nestin-positive type A cells. Our data indicate that GPs have neuroprotective effects during stroke which might be mediated through the enhancement of neurogenesis within the SVZ. These findings provide new evidence for a potential therapy involving GPs for the treatment of stroke.  相似文献   
86.
低氧诱导促有丝分裂因子(hypoxia-induced mitogenic factor,HIMF)是一类富含半胱氨酸的分泌蛋白.HIMF首先在炎症区域被发现,并且扮演着炎症细胞标志物的角色,HIMF同时又称作发现于炎症区域1(found in inflammatory zone 1,FIZZ1).由于该蛋白家族成员在低氧与炎症相关生理病理过程中起不可忽视的作用,国内外对该蛋白家族的研究越来越多.目前该因子在血管生长、平滑肌增殖、气道炎症、肠道免疫等方面的作用已有相关研究.  相似文献   
87.
We present a case of a novel pathogenic variant, Hb Kalavasos [α91(FG3)Leu→His (α2); HBA2: c.275T?>?A; p.Leu92His (NM_000517.4)]; this codon was previously numbered 91 on the α2-globin gene that was discovered following routine Hb A1c testing on a 65-year-old female of Cypriot origin. The band, seen by high performance liquid chromatography (HPLC) but not capillary zone electrophoresis (CZE), was confirmed as a hitherto undescribed a chain variant, that we have named Hb Kalavasos for the Cypriot village of family origin of the proband.  相似文献   
88.
Abstract

A case of dysembryoplastic neuroepithelial tumor in the left insular cortex manifesting with intractable seizures is presented. The multichannel magnetoencephalography (MEG) localized equivalent current dipoles of epileptic discharges at the cerebral cortex adjacent to the tumor. The total removal of the tumor resulted in complete disappearance of seizures. This case demonstrated that multichannel MEG was useful in the three-dimensional localization of irritative zone in the concealed cortices such as inside the sylvian fissure. [Neural Res 1998; 20: 433–438]  相似文献   
89.
An obligatory role for the calcium sensor synaptotagmins in stimulus-coupled release of neurotransmitter is well established, but a role for synaptotagmin isoform involvement in asynchronous release remains conjecture. We show, at the zebrafish neuromuscular synapse, that two separate synaptotagmins underlie these processes. Specifically, knockdown of synaptotagmin 2 (syt2) reduces synchronous release, whereas knockdown of synaptotagmin 7 (syt7) reduces the asynchronous component of release. The zebrafish neuromuscular junction is unique in having a very small quantal content and a high release probability under conditions of either low-frequency stimulation or high-frequency augmentation. Through these features, we further determined that during the height of shared synchronous and asynchronous transmission these two modes compete for the same release sites.  相似文献   
90.
Humoral immunodeficiency caused by mutations in the Wiskott-Aldrich syndrome protein (WASp) is associated with failure to respond to common pathogens and high frequency of autoimmunity. Here we addressed the question how deficiency in WASp and the homologous protein N-WASp skews the immune response towards autoreactivity. Mice devoid of WASp or both WASp and N-WASp in B cells formed germinal center to increased load of apoptotic cells as a source of autoantigens. However, the germinal centers showed abolished polarity and B cells retained longer and proliferated less in the germinal centers. While WASp-deficient mice had high titers of autoreactive IgG, B cells devoid of both WASp and N-WASp produced mainly IgM autoantibodies with broad reactivity to autoantigens. Moreover, B cells lacking both WASp and N-WASp induced somatic hypermutation at reduced frequency. Despite this, IgG1-expressing B cells devoid of WASp and N-WASp acquired a specific high affinity mutation, implying an increased BCR signaling threshold for selection in germinal centers. Our data provides evidence for that N-WASp expression alone drives WASp-deficient B cells towards autoimmunity.  相似文献   
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