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Various arguments suggest that CD8+ T lymphocytes play a major role in the control of cytomegalovirus (CMV) infection. The detection of CMV-specific CD8+ T cells may therefore provide additional information about CMV virus detection to predict the risk of development of CMV disease, especially in immunodepressed transplant recipients. We compared and tested various experimental conditions to optimize an enzyme-linked immunospot assay (Elispot) assay for the detection of CMV-specific CD8+ T lymphocytes. The indirect Elispot assay with one six-day in vitro sensitization step was found to be the most sensitive method to detect CMV-specific CD8+ T cells compared to direct Elispot with unfractionated peripheral blood mononuclear cells or purified CD8+ T cells. We showed that low doses of interleukin-2 during the in vitro culture enhanced the sensitivity of this test, and tetramer staining was performed to verify the high efficiency of this in vitro stimulation step. We directly loaded the specific CMV peptide during the Elispot assay and demonstrated that the use of T2 cells did not improve its sensitivity. Elispot for the detection of interferon-gamma appears to be more sensitive and reliable than measurement of tumor necrosis factor alpha or granzyme B. This technique was successfully applied to detect CMV-specific CD8+ T cells in human leukocyte antigen A2 (HLA-A2) and HLA-B7 healthy patients and in one lymphopenic post-transplant patient with positive CMV serology. This highly sensitive test may be a useful tool to assess T-cell immunity directed against CMV in immunodepressed patients.  相似文献   
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Mutations of the p53 gene are the most common genetic alteration in malignant human tumors. A cyclin-dependent kinase inhibitor, p21WAF1/CIP1, is thought to be an important mediator of p53-induced cell cycle arrest. Although numerous studies have reported p53 expression and mutation in colorectal cancer few of them have correlated p53 expression with that of its downstream effector p21 and with the proliferation index as measured by expression of the Ki67 nuclear antigen. We studied p53, p21 and Ki67 expression by immunohistochemistry and molecular biology in 35 colorectal carcinomas. We compared these findings with each other and with clinical factors. Sixty three percent of tumors expressed p53 whereas seventy one percent expressed p21WAF1/CIP1. In adenocarcinomas, p21 staining was heterogeneous: p21-reactive cells were seen in the most differentiated areas. There was no correlation between p21WAF1/CIP1 and p53 expression, p53 mutation, Ki67 expression or clinical factors such as sex or location of the tumor. On the other hand, there was a statistical relationship between p21 expression and survival: our results indicated an association between high p21 expression and lower stages p21WAF1/CIP1 appears to be induced independently of p53 in these tumors and may be associated with differentiation rather than proliferation.  相似文献   
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During the past 15 years, occupational therapists in Canada, through the Canadian Association of Occupational Therapists, have worked to develop and implement guidelines for practice of a client-centred approach to occupational therapy. One of the difficulties with the current Guidelines for the Client-Centred Practice of Occupational Therapy is the lack of a definition and discussion of the concepts and issues fundamental to client-centred practice. In this paper, key concepts of client-centred practice: individual autonomy and choice, partnership, therapist and client responsibility, enablement, contextual congruence, accessibility and respect for diversity are discussed. Two practice examples are used to illustrate these ideas and raise issues about obstacles to the practice of client-centred occupational therapy. Research evidence about the effectiveness of client-centred concepts in enhancing client satisfaction, functional outcomes and adherence to health service programmes is reviewed.  相似文献   
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An epidemiologic case-control study of 1617 patients with a primary breast cancer and 1617 control subjects was conducted to test the hypothesis that use of hair dyes is related to breast cancer. No overall association was observed between breast cancer risk and "ever use" of hair dyes (odds ratio, 1.04; 95% confidence interval, 0.90 to 1.21), age when hair dye use started and age when it stopped, duration of hair dye use (years), types of hair dyes used, and estimated lifetime number of individual applications. The current data set also failed to show an increased risk for breast cancer in women who had been diagnosed with benign breast disease and were exposed to hair dyes.  相似文献   
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By controlling the proper folding of proteins imported into mitochondria and ensuring crosstalk between the reticulum and mitochondria to modulate intracellular calcium fluxes, Mortalin is a chaperone protein that plays crucial roles in neuronal homeostasis and activity. However, its expression and stability are strongly modified in response to cellular stresses, in particular upon altered oxidative conditions during neurodegeneration. Here, we report and discuss the abundant literature that has highlighted its contribution to the pathophysiology of Parkinson’s disease, as well as its therapeutic and prognostic potential in this still incurable pathology.Key Words: chaperone, Hspa9, mitochondria, Mortalin, neurodegeneration, oxidative stress, Parkinson’s disease, prognostic and therapeutic potential  相似文献   
8.
This groundbreaking study focuses on the link between music-therapy and narrativity in a pediatric hematology-oncology unit. The goal is to observe and analyse the psychic processes in this therapeutic mediation. We aim to study the creative processes through the narrative productions of a sick and hospitalized teenagers. The interest of this original work with regard to previous research is to focus on the internal mechanisms of the patient and his narrative identity rather than on the active ingredient and the therapeutic method itself or its effect on a particular symptom. Based on a clinical situation of a young man of 19 years followed in onco-hematology, authors show how the creation of a sound link and subsequent narration on this sound object can be used as a “cordage” for seriously ill adolescents to endure the trauma of announcing the disease and announcing an imminent promise of death. We wish to support the issues of therapeutic support in order to demonstrate their resources with which they can subjectively assume their traumatic and painful journey, in this very specific space-time. His text, reproduced in appendix, is the subject of a literary analysis then of a psychopathological discussion.  相似文献   
9.
Liver fibrosis (LF) must be assessed before talking treatment decisions in hepatitis B. In Burkina Faso, liver biopsy (LB) remains the “gold standard” method for this purpose. Access to treatment might be simpler if reliable alternative techniques for LF evaluation were available. The hepatitis B virus (HBV)-infected patients who underwent LB was invited to have liver stiffness measurement (Fibroscan) and serum marker assays. Fifty-nine patients were enrolled. The performance of each technique for distinguishing F0F1 from F2F3F4 was compared. The area under receiver operating characteristic (AUROC) curves was 0.61, 0.71, 0.79, 0.82, and 0.87 for the aspartate transaminase to platelet ratio index (APRI), Fib-4, Fibrotest, Fibrometre, and Fibroscan. Elastometric thresholds were identified for significant fibrosis and cirrhosis. Combined use of Fibroscan and a serum marker could avoid 80% of biopsies. This study shows that the results of alternative methods concord with those of histology in HBV-infected patients in Burkina Faso. These alternative techniques could help physicians to identify patients requiring treatment.  相似文献   
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Recent studies have shown that in addition to being major constituents of the atheromatous core, solid cholesterol crystals (CCs) promote atherosclerotic lesion development and rupture by causing mechanical damage and exerting cytotoxic and pro‐inflammatory effects. These findings suggest that targeting CCs might represent a therapeutic strategy for plaque stabilization. However, little is known about how cholesterol crystallization is initiated in human atherothrombotic disease. Here, we investigated these mechanisms. We performed a thorough immunohistological analysis of non‐embedded, minimally processed human aortic tissues, combining polarized light and fluorescence microscopy. We found that CC formation was initiated during the fatty streak to fibroatheroma transition in tight association with the death of intralesional smooth muscle cells (SMCs). Cholesterol‐loaded human SMCs were capable of producing CCs in vitro, a process that was enhanced by type I collagen and by inhibition of autophagy and cholesterol esterification. The fibrous transition, which was characterized by increased type I collagen expression, was associated with changes in the expression of autophagy and cholesterol flux‐related genes, including a decrease in the autophagic adapter p62 and an increase in the cholesterol intracellular transporter Niemann–Pick C1. Collagen was identified as a potent inducer of these changes in SMCs. Collagen‐induced changes in cholesterol metabolism and autophagy flux in smooth muscle foam cells at the fibrolipid transition likely contribute to initiate cholesterol crystallization in human atherosclerosis. Also, our data are in support of a protective role of autophagy against CC formation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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