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91.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
92.
Why study transport of peptides and proteins at the neurovascular interface   总被引:2,自引:0,他引:2  
The blood–brain barrier (BBB) is an immense neurovascular interface. In neurodegenerative, ischemic, and traumatic disorders of the central nervous system (CNS), the BBB may hinder the delivery of many therapeutic peptides and proteins to the brain and spinal cord. Fortunately, the mistaken dogma that peptides and proteins do not cross the BBB has been corrected during the past two decades by the accumulating evidence that peptides and proteins in the periphery exert potent effects in the CNS. Not only can peptides and proteins serve as carriers for selective therapeutic agents, but they themselves may directly cross the BBB after delivery into the bloodstream. Their passage may be mediated by simple diffusion or specific transport, both of which can be affected by interactions in the blood compartment (outside the BBB) and within the endothelial cells (at the BBB level). Although the majority of current delivery strategies focuses on modification of the molecule to be delivered, understanding the mechanisms of transport will eventually facilitate regulation of the BBB directly. We review the different aspects of interactions and discuss recent advances in the cell biology of peptide/protein transport across the BBB. Better understanding of the nature and regulation of the transport systems at the BBB will provide a new direction to enhance the interactions of peripheral peptides and proteins with the CNS.  相似文献   
93.
原发性肝癌患者肝切除术前、后免疫细胞表型分析   总被引:1,自引:1,他引:0  
目的研究原发性肝癌(PrimaryLiverCarcinoma,PLC)患者肝切除术前、后免疫细胞表型的变化。方法采用直接免疫荧光标记,流量血细胞计数法(FlowCytometry,FCM)检测方法,动态观察120例PLC患者肝切除术前后外周血T淋巴细胞亚群、NK细胞和HLA鄄DR含量变化。结果肝切除术前肝功能Child鄄PughB级、OGTTL型和术前施行肝动脉栓塞化疗患者外周血CD8+T细胞含量明显低于正常人组,CD4+/CD8+比值则较高(P<0郾05)。全部肝癌患者肝切除术前、后CD3+CD4+T细胞和NK细胞(CD3-CD16+CD56+)含量无明显差异。术后第1天、第3天、第7天和第2周外周血淋巴细胞CD3+CD8+含量明显低于肝切除术前和术后第3周(P<0.01);而CD4+/CD8+比值则显著高于肝切除术前和术后第3周(P<0郾01)。结论PLC合并肝硬变肝储备功能不足、术前肝动脉栓塞化疗和肝切除术可导致机体细胞免疫功能低下,PLC患者肝切除术前行肝动脉栓塞化疗的价值有待深入研究。  相似文献   
94.
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.  相似文献   
95.
The thymus in seronegative myasthenia gravis patients   总被引:1,自引:0,他引:1  
Summary In 5–10% of all patients with typical generalised myasthenia gravis (MG), serum antibody to the acetylcholine receptor (AChR) is undetectable. To determine whether these represent a distinct subgroup, we have compared the thymuses of 14 seronegatives, 70 seropositives and 12 non-myasthenic controls. By quantitative immunohistology on coded sections, the 7 seronegative samples were clearly distinguishable from the controls by the pronounced lymph node-type T-cell areas in the medulla. While these closely resembled those in the seropositive cases, germinal centres were significantly sparser, and total in vitro IgG production was disproportionately low (per B cell) in the 12 cases tested. Furthermore, specific anti-AChR production was never detected in any of these cultures. The data support the view that the medullary T-cell areas are the most consistent abnormalitiy in the MG thymus (though it may not be primary), and they strongly imply that seronegative and seropositive MG are distinct entities.  相似文献   
96.
Background Dendritic cells (DC) mediate inflammation in rodent models of allergic airway disease, but the role played by human respiratory‐tract DC (hRTDC) in atopic asthma remains poorly defined. Recent data suggest that CD1 antigen presentation by hRTDC may contribute to asthma pathogenesis. Objective To investigate the influence of hRTDC on the balance between atopy and allergic asthma in human subjects and to determine whether CD1 expression by hRTDC is modulated during asthmatic inflammation. Methods Sputum cells were induced from steroid‐naïve, allergen‐challenged and allergen‐naïve subjects (atopic asthmatics, atopic non‐asthmatics and non‐atopic controls). hRTDC were identified using monoclonal antibody labelling and analysis by flow cytometry. Results hRTDC stained HLA‐DR+ (negative for markers of other cell lineages) were predominantly myeloid and comprised ∼0.5% of viable sputum cells. Sputum cells were potent stimulators of allogeneic CD4+ naïve T cells and enrichment/depletion experiments correlated stimulatory potency with DC numbers. Sputum contained cells that exhibited typical dendritic morphology when analysed by electron microscopy. Myeloid hRTDC were endocytically active, but uptake of FITC‐dextran was enhanced in cells from asthmatics (P<0.001). Despite their increased endocytic capacity, asthmatic myeloid hRTDC appeared mature and expressed increased levels of maturation markers (P<0.05–P<0.001), CD1c, CD1d and langerin (P<0.05). CD1c expression by asthmatic myeloid hRTDC was enhanced upon in vivo allergen challenge (three to ninefold within 24 h; P<0.05). CD11cCD123high hRTDC were only detected in asthmatic sputum and were increased in number following allergen challenge. Conclusion Despite limited cell numbers, it proved possible to analyse human RTDC in induced sputum, providing evidence that increased antigen uptake and enhanced CD1 presentation by activated hRTDC may contribute to allergic airway disease. CD1 presentation by hRTDC in atopic asthma may therefore constitute a novel target for future intervention strategies.  相似文献   
97.
Malignant melanoma causes significant health problems. The identification of tumour-associated antigens has led to novel approaches to increase T cell mediated anti-tumour immune response. Melan-A/MART-1 has been use as target antigen for several T cell based immunotherapeutic treatments. More recently, the critical role of CD4+ T cells in inducing and maintaining anti-tumour immunity has been increasingly recognized. In order to optimize tumour immunotherapy, greater efforts have been concentrated on the identification of tumour antigens presented by MHC class II molecules to CD4+ T cells. In a publication, Tiwari et al. (2004) [1] have identified by a computational approach the 15-mer amino-acid sequence 101–115 (PPAYEKLSAEQSPPP) of the Melan-A/MART-1 as a good target for a vigorous and safe immunotherapy. Therefore, we have investigated the in vivo anti-tumour activity of this peptide in a murine melanoma model. For the prophylactic treatment, 20 μg or 50 μg peptide was subcutaneously injected in mice once a week during 3 weeks before tumour induction. Treatment with 50 μg peptide significantly affected tumour development. Thus, our preliminary data demonstrate potential in vivo prophylactic activity of the 101–115 peptide-based vaccine to control melanoma growth.  相似文献   
98.
Lymphoid clusters (LC) containing CD20-positive B cells in kidney allografts undergoing acute cellular rejection (ACR) have been identified in small studies as a prognostic factor for glucocorticoid resistance and graft loss. Allograft biopsies obtained during the first episode of ACR in 120 recipients were evaluated for LC, immunostained with CD20 antibody, and correlated with conventional histopathologic criteria, response to treatment and outcome. LC were found in 71 (59%) of the 120 biopsies. All contained CD20 positive B cells that accounted for 5-90% of the LC leukocyte content. The incidence of LC was highest in the patients who had no lymphoid depletion or had been treated with Thymoglobulin preconditioning (79% vs. 75%, respectively) compared to 37% in patients pretreated with Campath (p = 0.0001). Banff 1a/1b ACR were more frequent in the LC-positive than the LC-negative group (96% vs. 80%, respectively; p = 0.0051). With a posttransplant follow-up of 953 +/- 430 days, no significant differences were detected between LC-postitive and LC-negative groups in time to ACR, steroid resistance, serum creatinine and graft loss. CD20+LC did not portend glucocorticoid resistance or worse short to medium term outcomes. CD20+LC may represent a heterogenous collection in which there may be a small still to be fully defined unfavorable subgroup.  相似文献   
99.
The aim of this study was to examine the effect of purple coneflower (Echinacea purpurea L. Moench) on the prostate gland of rats using an experimental model of benign prostate hyperplasia (BPH). The animals were administered 50 mg/kg of extract preparation for 4 and 8 weeks and the prostate mass and structural degenerative changes were evaluated in the course of the experiment. The administration of E. purpurea extract to rats with hyperplasia for 4 and 8 weeks gradually and significantly reduced the prostate mass and reversed the degenerative changes in the structure of the prostate gland. The present investigation suggests extract of purple coneflower prevents the development of BPH. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
100.
Due to the shortage of human organs, xenotransplantation is being explored as an alternative to allotransplantation, but immune rejection remains a major hurdle to its implementation. We tested the ability of human CD4+CD25+ T cells (Treg cells) to suppress CD4+ T cell-mediated anti-porcine xenoresponses usingin vitroassays. Human Treg cells were hyporesponsive to porcine cell stimulation and suppressed the proliferative response of CD4+CD25- T cells in a dose-dependent manner, and comparison of the allo- and xenoresponses indicated that more Treg cells might be required to suppress the xenogeneic response than the allogeneic response. Stimulation of CD4+CD25- T cells with porcine cells resulted in secretion of IFN-gamma, TNF-alpha, IL-10, IL-6 and IL-2, and Treg cells suppressed the secretion of these cytokines, as well as the CD4+CD25- T-cell cytolytic response against porcine cells. These results suggest a potential role for Treg cells in promoting xenograft survival.  相似文献   
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