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991.
992.
Esophageal motor abnormalities are currently categorized into separate entities based on standard manometry. The clinical significance of these categories is controversial. We evaluated whether ambulatory 24-h esophageal motility monitoring improves the assessment of patients thought to have a primary esophageal motor disorder. Standard and ambulatory 24-h esophageal motility records of 30 healthy volunteers and 136 symptomatic patients were compared. Regression analysis was used to identify parameters that relate to the presence of nonobstructive dysphagia. Prolonged ambulatory esophageal monitoring showed a marked circadian variation in the esophageal motor pattern and significant discrepancies to the findings on standard manometry in 47% of the 136 patients. Discrepancies were particularly frequent in patients categorized on standard manometry as having a 'nutcracker esophagus' or a nonspecific motor disorder. Of all data obtained, the prevalence of 'effective contractions', i.e. peristaltic contractions with an amplitude > 30 mmHg, during meal periods provided the best correlation with the presence of nonobstructive dysphagia. Of the 78 patients with nonobstructive dysphagia 71 (92%) had less than 50% of 'effective contractions' during meals. In five patients who had frequent simultaneous wave forms and less than 70%'effective contractions' during meals a long myotomy markedly reduced the severity of dysphagia. The 'efficacy' of esophageal contractions during meals best relates to patients' symptoms and allows expression of esophageal body dysfunction on a linear scale. This obviates the need for the current categories of esophageal motor disorders, permits an objective assessment of medical therapy and may improve the identification of patients that benefit from a surgical myotomy of the esophageal body.  相似文献   
993.
The heterogenous group of anaplastic large cell lymphomas (ALCLs) is characterized by expression of the Ki-1/CD30 antigen, a member of the tumor necrosis factor receptor superfamily. About 40 to 50% of cases diagnosed as ALCL contain a specific chromosomal rearrangement, t(2;5)(p23;q35), resulting in expression of the chimeric tyrosine kinase NPM-ALK. As NPM-ALK-positive lymphomas define a distinct subtype within the group of ALCL, the chimeric protein might be responsible for certain pathogenetic and clinicopathologic characteristics. To better elucidate the function of NPM-ALK, we investigated a possible mechanism for regulation of its activity. We demonstrate that NPM-ALK specifically binds to the intracellular domain of the cytokine receptor CD30. In vitro binding assays revealed that the ALK portion of NPM-ALK mediates interaction of the two proteins. Stimulation of the CD30 receptor by cross-linking with immobilized anti-CD30 antibody results in complete growth inhibition of Karpas 299, an NPM-ALK-positive ALCL cell line, but does not alter proliferation of HDLM-2, a Hodgkin's lymphoma-derived cell line lacking t(2;5). Western blot analysis of coimmunoprecipitated CD30 and NPM-ALK proteins from stimulated Karpas 299 cells showed that the interaction of the proteins is not modified by stimulation. Activation of CD30 neither enhanced NPM-ALK activity measured by autophosphorylation of the chimeric tyrosine kinase nor phosphorylation of phospholipase C-gamma, an NPM-ALK substrate. We conclude that NPM-ALK is not stimulated by CD30 activation, but exists as a constitutively hyperactivated protein. Interaction with CD30 may extend the subcellular localization of NPM-ALK to the microenvironment of membrane-associated proteins.  相似文献   
994.
目的:探讨CD44v6蛋白表达与胰腺癌增殖及淋巴结转移的关系。方法:应用免疫组织化学(S-P)法检测38例胰腺癌组织标本中CD44v6和PCNA的表达。结果:CD44v6在胰腺癌中的阳性率为65%(25/38),与淋巴结转移呈非常显相关(P<0.01),与胰分化程度无关(P>0.05)。CD44v6阳性染色胰腺组织中PCNA标记率较阴性高(P<0.05)。结论:CD44v6在胰腺癌的增殖,转移过程中可能起重要作用,可作为胰腺癌预后预测的生物学指标之一。  相似文献   
995.
The aim of this study was to quantify and characterise the CD4+ and CD8+, CD45RA+, CD45RO- T-lymphocytes that paradoxically expressed the CD29 bright+ phenotype in health and in rheumatoid arthritis. We further evaluated their clinical implications. Blood samples were obtained from 100 patients with rheumatoid arthritis and 40 age- and sex-matched controls. Cell surface antigens and interleukin-2 (IL-2) binding were detected on CD4+ and CD8+ peripheral blood T-lymphocytes (T-PBL) by three-colour flow cytometry. One-third of the patients were clinically evaluated at the time of blood sampling. In healthy donors, we found 16 ± 14% of CD29 bright+cells among CD4+, CD45RA+, RO-T-PBL. These false naive CD4+ T-PBL were Leu-8+, and a majority expressed the CD25/p55 receptor (IL-2R chain), while a minority showed the CDlla bright+, CD69+ and/or CD 122/p75+ (IL-2R chain) phenotype, and few cells were CD31 bright+ and HLA-DR+. In rheumatoid arthritis, their proportion among CD4+, CD45RA+, RO- cells increased to 25 ± 15% (P < 0.001, compared with controls). In patients, the reductions in CD31 and CD38 expression (P < 0.05 for both), as well as the enhanced CD25 expression (P < 0.001) on CD4+, CD45RA+, RO- T-PBL reflected a more differentiated phenotype. The occurrences of CD25 and CD122 were increased on false naive CD4+ T-PBL (0.01 <P<0.001); however, the binding of IL-2 remained very low (in contrast to the binding of IL-2 on CD45RO+ T-PBL). Furthermore, a major subset of CD8+, CD45RA+, RO- T-PBL (45 ± 17% in controls) expressed the CD29 bright+ phenotype. These false naive CD8+ T-PBL included a great many of CID 1lb+, CD28- cells, while a minority showed the HLA-DR+, CD69+ and/orCD122+ phenotypes. Patients with low levels of IgM rheumatoid factors (IgM-RF; but with active disease) had an elevated proportion of CD45RA+, RO-cells among the CD8+ T-PBL, in part due to an increased proportion of false naive cells (P < 0.05). In patients, the false naive CD8+ T-PBL showed down-regulated CD1lb and an increased expression of IL-2 receptor chains (CD25 and CD 122; 0.05 <P < 0.01), but without a significant increase in IL-2 binding. More CD69 on false naive CD8+ T-PBL was found in patients with high levels of IgM-RF (P < 0.005 compared to patients with low 19M-RF). Finally, both false naive CD4+ and CD8+ T-PBL correlated with the clinical process and outcome variables (0.05 <P <0.01). The levels of activated false naive CD4+ T-PBL (CD25+ and/or CD122+) or CD8+ T-PBL (CD69+ and/or CD122+) were associated with clinical parameters of disease activity (0.05 <P < 0.01). Thus, in rheumatoid arthritis, false naive T-PBL showed important qualitative differences. The levels of activated false naive T-PBL could be particularly interesting for monitoring disease evolution.  相似文献   
996.
The platelet-type thrombin receptor was the first member to be identified in a family of protease activated receptors (PARs) and has been designated PAR-1. We recently reported that the large granular lymphocytes (LGLs) in patients with proliferations of CD8+ cells co-expressed PAR-1 and the expression of PAR-1 correlated with the expression of CD57. Here we show, by three-colour immunofluorescence, that the LGLs from a patient with a rare CD4+ CD57+ monoclonal expansion also expressed PAR-1. Northern blot analysis confirmed the presence of high levels of mRNA for PAR-1 in these LGLs.  相似文献   
997.
The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF.  相似文献   
998.
Purpose This study was conducted to evaluate the prognostic significance of CD44v5 and CD44v6 in resectable colorectal cancer.Materials and methods Membranous CD44v5 and CD44v6 levels were measured by an immunoenzymatic assay in tumors and surrounding mucosal samples obtained from 105 patients with resectable colorectal carcinomas.Results There were no significant differences of CD44v5 levels between tumors [median: 3.2 (range: 0.9–83.5) ng/mg protein) and surrounding mucosal samples (3 (3–146.2) ng/mg protein]. However, tumor samples showed significantly higher CD44v6 levels [19.5 (2.2–562.9) ng/mg protein] than mucosal samples [5 (5–230) ng/mg protein] (P=0.0001). Patients with higher CD44v5 or CD44v6 content in tumor samples had a considerably shorter relapse-free survival (P<0.05, for both). Patients with a higher CD44v6 content also had a shorter relapse-free and overall survival in the multivariate analysis (P<0.05).Conclusion The results of this study suggest a role of CD44v5 and CD44v6 in colorectal cancer progression. Membranous CD44v levels in primary tumors, measured by immunoenzymatic assay, may contribute to a more precise prognostic estimation in patients with resectable colorectal cancer.Supported by grants from ISCIII Red de Centros de Cancer RTICCC (C03/10) and Obra Social Cajastur  相似文献   
999.
CD34+-selected peripheral blood progenitor cells (PBPCs) may not only reduce contaminated tumor cells but also compromise immunologic reconstitution and increase incidence of infections after transplantation. We analyzed the incidence of virus reactivation in CD34+-selected PBPCs autologous transplantation. From December 2001 to December 2004, ten high-risk aggressive non-Hodgkin’s lymphoma (NHL) patients were enrolled in a program of high-dose chemotherapy plus autologous CD34+-selected PBPCs support. Viral screening studies, including clinical symptoms, physical examinations, hepatitis B virus (HBV)-DNA, cytomegalovirus (CMV)-polymerase chain reaction (PCR), rapid diagnosis of fluorescent antibody stain for herpes-simplex virus (HSV), and viral culture from blood, fluid or tissue were performed weekly during the first 3 months and then monthly for 1 year. Two of four patients (50%) who were HBV carriers developed HBV reactivation. The other two HBV carriers who received prophylactic lamivudine therapy did not develop HBV reactivation. Two patients (20%) developed cytomegalovirus (CMV) infection, and three patients (30%) developed HSV infection in total ten serum-positive patients. The possibility of virus reactivation might increase in NHL patients undergoing autologous CD34+-selected PBPC transplantation. Administering prophylactic antivirus therapy and closely following patient’s clinical viral complications should be considered.  相似文献   
1000.
Dendritic cells (DCs) play a central role in antiviral immunity. Conflicting data on DC function have been reported for hepatitis C virus (HCV) infection. In addition to antigen presentation and cytokine secretion, a subset of human DCs displays direct cytotoxic activity. It has been suggested that measles virus and human immunodeficiency virus (HIV) may enhance cytotoxicity of DCs potentially leading to apoptosis of activated T cells and subsequent down-regulation of antiviral immune responses. We demonstrate that CD1c-positive myeloid DCs, but not BDCA-4-positive plasmacytoid DCs, are able to kill different target cells mainly via tumour necrosis factor-related apoptosis-inducing ligand. The ability of CD1c+ DCs to lyze target cells was found to be completely impaired in patients with chronic hepatitis C (10 chronic HCV patients vs 10 healthy controls; P < 0.001) but not in patients with primary biliary cirrhosis. Successful antiviral therapy of chronic hepatitis C rescued the cytotoxicity of DCs. Myeloid DCs of HCV patients and healthy controls had a similar phenotype and endocytotic activity, however, the frequency of mDCs in the peripheral blood was lower (P = 0.004) and the allostimulatory function was weaker (P < 0.001) in chronic hepatitis C. Thus, in contrast to HIV and measles virus studies on monocyte-derived DCs, freshly isolated myeloid DCs of patients with hepatitis C do not show an increased but a completely abolished cytotoxic activity. The impaired DC cytotoxicity could represent a novel mechanism for the increased prevalence of autoimmunity in HCV infection.  相似文献   
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