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991.
Biclonal expansion of T cells infected with monoclonal Epstein-Barr virus (EBV) in a patient with chronic,active EBV infection 下载免费PDF全文
Recent studies have suggested that a high percentage of Epstein-Barr virus (EBV)-infected lymphocytes in peripheral blood of patients with chronic, active EBV infection (CAEBV) is of T cell origin. Although T cells are expanded oligoclonally in CAEBV, it is not clear whether the restricted diversity of T cells arise from immune reaction against EBV-related antigens or from proliferation of EBV-infected cells. We experienced a patient with CAEBV who had biclonal expansion of peripheral blood T cells. We identified clonotypes of these two T cell clones in detail and purified the T cell clones. EBV infected mainly the two T cell clones, whereas the viral loads in peripheral blood cells other than these T cell clones were low or undetectable. The EBV strains infecting the two T cells clones were indistinguishable from each other by a series of genotype analyses of the virus. These results suggest that the two T cell clones infected with the same monoclonal EBV proliferated in peripheral blood of the patient. 相似文献
992.
Superantigen-induced T cell responses in acute rheumatic fever and chronic rheumatic heart disease patients 总被引:3,自引:0,他引:3
CD4+ and CD8+ T cells from healthy donors, acute rheumatic fever (ARF) and chronic rheumatic heart disease (CRHD) patients responded variably to a superantigen from Streptococcus pyogenes--Streptococcal pyrogenic erythrogenic toxin A (SPE-A). In vitro culture of CD4+ T cells from ARF patients (CD4-ARF) with SPE-A exhibited a Th1 type of response as they produced high levels of IL-2, while CD4+ T cells from CRHD patients (CD4-RHD) secreted IL-4 and IL-10 in large amounts, i.e. Th2 type of cytokine profile. The skewing of human CD4+ T cells (in response to SPE-A stimulation) to Th1 or Th2 type reflects the role of the two subsets in a disorder with differing intensities at the two extremes of the spectrum. Moreover, the anergy induction experiments revealed that CD8-ARF and CD8-RHD undergo anergy (to different extents), whereas CD4+ T cells do not, in response to re-stimulation by SPE-A. These results initially demonstrate that both CD4+ and CD8+ T cells respond differentially to SPE-A, and hence it is an important observation with respect to the pathogenesis of ARF/CRHD. Anergy in CD8+ T cells in the presence of SPE-A in vitro goes a step further to show the clinical relevance of these cells and their possible role in suppression of the disease. 相似文献
993.
OBJECTIVE: The aim of this study was to explore the role of rhinoconjunctivitis (RC), taking into account atopy and the level of bronchial responsiveness to methacholine, on the incidence of respiratory symptoms and in the development and/or worsening of asthma. METHODS: We examined data from a prospective study in 769 students starting exposure to high-molecular-weight occupational allergens and who were serially followed for up to 44 months. RESULTS: The presence of RC symptoms at baseline was significantly associated with an increased risk of developing shortness of breath and wheezing in atopic subjects regardless of PC20 level and in subjects with a PC20 相似文献
994.
目的探讨中枢神经系统感染患儿血脑屏障(blood-brain barrier,BBB)与脑脊液(cerebrospinal-fluid,CSF)白蛋白指数的变化。方法采用溴甲酚绿法和免疫比浊法检测18例化脓性脑膜炎患儿急性期、恢复期及22例病毒性脑炎患儿急性期血清和CSF中白蛋白水平,并计算出CSF白蛋白指数。与正常对照组比较。结果化脓性脑膜炎、病毒性脑炎患儿急性期CSF白蛋白、CSF白蛋白指数显著高于正常对照组(P〈0.001),且化脑组显著高于病脑组(P〈0.001)。化脑组恢复期患儿CSF白蛋白、CSF白蛋白指数与对照组无明显差异(P〉0.05)。结论监测CSF白蛋白和CSF白蛋白指数的水平可作为化脓性脑膜炎和病毒性脑炎早期诊断、鉴别诊断,以及判断BBB损伤程度的参考指标。 相似文献
995.
Influence of an established acute phase response on the severity of experimental nephritis. 下载免费PDF全文
Small doses of lipopolysaccharide (LPS) induced an acute phase response (APR), and a number of studies have also shown that this greatly enhances the severity of glomerular injury in the heterologous phase of nephrotoxic nephritis (hNTN), an experimental model of anti-glomerular basement membrane (GBM) disease. Here, we examined the influence of pre-existing subclinical infection and raised APR, assessed by plasma alpha 2-macroglobulin (alpha 2-M) concentration, on the degree of injury in this model of nephritis. Studies were initially performed to determine the normal range of alpha 2-M in rats and its modulation by IL-6 and different doses of LPS. Plasma concentration of alpha 2-M was found to be variable and dependent on the weight of the rats. Single injections of either LPS or IL-6 had a comparable effect, and continuous perfusions of LPS caused a progressive increase in alpha 2-M which peaked at 48 h and declined gradually over 1 week. Following induction of nephritis with 10 mg of anti-GBM antibody, rats with raised alpha 2-M had 14 +/- 3 mg/24 h albuminuria compared with 4 +/- 1 mg/24 h in rats with normal alpha 2-M (P < 0.001, Wilcoxon). Injection of 20 mg anti-GBM antibody caused 36 +/- 11 mg/24 h albuminuria compared with 16 +/- 4 mg/24 h (P < 0.001), respectively. However, all these rats remained active and none of them died. In contrast, injection of 0.25 microgram LPS before induction of nephritis with 10 mg anti-GBM antibody, in rats with raised alpha 2-M, caused severe albuminuria (115 +/- 23 mg/24 h) compared with rats having normal levels of alpha 2-M (72 +/- 15 mg/24 h, P < 0.05). Furthermore, rats with raised alpha 2-M also had severe systemic manifestations characterized by pulmonary haemorrhage and extensive glomerular thrombosis, and many of them died. These results demonstrate the potential effect of pre-existing subclinical infection and raised APR on severity of glomerular injury which may affect the outcome of experimental studies. 相似文献
996.
Jonathan T. Sims Venkatesh Krishnan Ching-Yun Chang Sarah M. Engle Giacomo Casalini George H. Rodgers Nicoletta Bivi Brian J. Nickoloff Robert J. Konrad Stephanie de Bono Richard E. Higgs Robert J. Benschop Silvia Ottaviani Anabela Cardoso Ajay Nirula Mario Corbellino Justin Stebbing 《The Journal of allergy and clinical immunology》2021,147(1):107-111
997.
Steffanie Sabbaj Michael F. Para Robert J. Fass Patrick W. Adams Charles G. Orosz Caroline C. Whitacre 《Journal of clinical immunology》1992,12(3):216-224
The lymphocyte proliferative response to recall antigens is lost following HIV infection. We sought to devise a means by which the functional immune status of persons in the early stages of HIV infection could be monitored quantitatively. The response to tetanus toxoid was examined in 45 HIV-infected individuals and 11 controls using conventional lymphocyte proliferative assays concurrently with limiting dilution analysis utilizing the secretion of interleukin-2 as the measure of a response. Our data show that the limiting dilution analysis detects tetanus toxoid-reactive T cells in 80% of those tested, as compared to only 44% by proliferation. However, the frequency of tetanus-reactive T cells in HIV-infected individuals (median frequency = 1/59,156) is decrease five-fold as compared to seronegative controls (median frequency = 1/11,599). Longitudinal studies demonstrated a time-dependent decrease in the frequency of tetanus-specific T cell responses in the HIV-infected individuals. Thus, the limiting dilution analysis is a quantitative approach for detecting antigen-specific T cells in HIV-infected individuals, and may be used to monitor changes in T cell function in HIV infection. 相似文献
998.
Tubbs RS Oakes WJ Salter EG Zehren SJ 《Anatomical science international / Japanese Association of Anatomists》2004,79(2):98-100
We report an adult male cadaver with persistence of the ductus arteriosus and a right retroesophageal artery. The retroesophageal artery was first appreciated as a retropharyngeal mass during the dissection of this area. Both the left and right vertebral arteries originated in normal fashion. The thoracic duct of our specimen drained into the junction of the left internal jugular and left subclavian veins. We believe this to be the first report of simultaneous right retroesophageal subclavian artery and patent ductus arteriosus. The anatomy and embryology of these two anomalies in the same specimen are discussed. 相似文献
999.
O. V. Shadrin N. A. Khar'kovskaya O. M. Dronova S. N. Bykovskaya 《Bulletin of experimental biology and medicine》1992,114(4):1466-1468
Laboratory of Cellular Immunity and Laboratory of Bacteriology, Department of Laboratory Animals. Oncologic Scientific Center, Russian Academy of Medical Sciences, Moscow. (Presented by Academician of the Russian Academy of Medical Sciences N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 10, pp. 383–385, October, 1992. 相似文献
1000.
Inoculation of fertile Pekin duck eggs with diluted serum containing DHBV into eggs incubated for 24 h and into the extra-embryonic cavities of 14-day-old embryos resulted in a high proportion of viraemic ducklings irrespective of the route of inoculation. Long-term observation of som of the ducks established that the viraemia induced experimentally is long-lasting and has persisted for periods up to 16 mth post-hatch. Separation of DHBV from the plasma of carrier ducks by rate zonal centrifugation was examined by DNA polymerase (DNAP) activity. Particles in the fraction with peak DNAP activity had a buoyant density of 1.16 g X cm-3 in sucrose and an estimated sedimentation coefficient, S20.w of 77. DHBV particles, the morphology of which could be resolved under the electron microscope, consisted of a coat (about 10 nm in thickness) surrounding a core with a diameter measuring 40 nm but not 27 nm as previously reported. Spike-like projections were found on the surface of the core as described previously by W.S. Mason, G. Seal and J. Summers, 1980, J. Virol. 36, 829-836. 相似文献