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31.
Human xenoreactive natural antibodies of the IgM isotype activate pig endothelial cells 总被引:1,自引:0,他引:1
Abstract: Preformed, xenoreactive natural antibodies (XNA) and complement (C) are involved in the initiation of vascular rejection of organs transplanted between discordant species, presumably by stimulating donor organ endothelial cells (EC). Although C is known to play a role in the activation of EC, it has not been clear whether the antibodies serve only to anchor the initial components of C, and thus permit the C cascade to proceed, or whether the antibodies themselves deliver a signal to the EC. We have tested affinity-purified human IgM containing XNA (IgM-XNA) for its ability to stimulate in vitro the up-regulation of genes in pig EC. Northern blot analysis shows that IgM, which contains XNA, stimulates mRNA accumulation for certain genes (including IL-8, PAI-1, and ECI-7, a new gene that we have found is associated with EC activation), but not others known to be up-regulated in response to TNF, IL-1 or LPS. Our results show that XNA provide a signal to EC, and thus may themselves participate in activation of EC and consequent vascular rejection. 相似文献
32.
Michael R. Perkin David P. Strachan Hywel C. Williams Cameron T. C. Kennedy Jean Golding the ALSPAC Study Team 《Pediatric allergy and immunology》2004,15(3):221-229
We investigated the natural history of atopic dermatitis (AD) in a population-based birth cohort and assessed whether children at risk of visible eczema at 5 years of age can be identified from total immunoglobulin E (IgE) levels measured at 8, 12 and 18 months. AD data collected included a whole body examination for visible eczema at 49 months (4 years) and 61 months (5 years) of age and parent completed questionnaire data throughout their early lives. Children were divided into four groups based on their natural history of early AD: persistent (AD at 1, 6, 18, 30 and 42 months, n = 34), intermittent early onset (before 18 months of age, n = 495), intermittent late onset (18–42 months of age, n = 273) and unaffected ( n = 429). Visible eczema at 5 years of age was present in 12.2% (117/957) (95% confidence interval [CI] 10.1–14.3%) of the children. Levels of total IgE at 8, 12 and 18 months of age were associated with early onset of AD, but not with AD of later onset. For all four natural history groups, the geometric mean total IgE at 12 months was higher in those who subsequently had visible eczema than those who did not. However, the degree of overlap was such that total IgE at 12 months of age was a poor predictor of eczema at age five. A cutoff point of 78 kU/l had the highest positive predictive value for visible eczema at 5 years of age of 28.6%, with a sensitivity of 12% and specificity of 95%. 相似文献
33.
提高中医临床疗效的科学学检讨(连载三) 总被引:1,自引:0,他引:1
李致重 《河南中医学院学报》2003,18(6):5-7
中医学的生命力在于临床疗效 ,社会对于中医学的需要也在于临床疗效。提高中医临床疗效的科学学研究 ,要以中医基础理论为依据 ,以理、法、方、药一脉相承的辨证论治为前提。造成中医临床疗效下降的问题在于“三个脱节” ,即中医学与自身文化基础脱节 ,中医临床与辨证论治脱节 ,中药与中医临床脱节。中医学正处于行将消亡的边缘 ,也处在新的突破的前夜。实事求是地进行科学、历史的反思 ,中医学完全有可能走出百年困惑 ,得到振兴和发展。 相似文献
34.
Summary In order to study the immune function of patients on maintenance hemodialysis (MHD), we assayed NK cell cytotoxicity against
K562 targets in 40 patients on MHD, and the production of IL-2 and IFN in peripheral blood mononuclear cells (PBMC) after PHA
stimulation, in contrast to those in normal controls. The results showed that NK cell activity and IL-2 and IFN levels were
markedly lower in the patients than in the controls. Afeter a single dialysis, NK cell activity as well as IL-2 and IFN levels
were elevated to different extent. But there was no significant change in patients after long-term dialysis. There was a positive
correlation between the NK cell activity and IL-2 and IFN activity in the controls, but no such correlation was found in the
patients on MHD. There was a positive correlation between the NK cell activity and IL-2 activity in patients after dialysis,
suggesting that immune function were impaired in the patients on MHD, with a decline in the activity of NK cell and IL-2 and
IFN, and a disorder of immune regulation cycle. These abnormal immune impairments in the patients could be partly corrected
by hemodialysis. However, long-term hemodialysis is not much helpful in the improvement of patient’s immune function. 相似文献
35.
将一种快速、灵敏、可靠、简便的抗癌活性微量测定技术——~3H—TdR前体掺入技术用于复方中药抗癌制剂制备工艺筛选,短期内即拟定出较合理的工艺,经临床及14项生物学指标综合评定,该制剂疗效好,无明显的毒副作用。表明把一些快速、灵敏的医学检测技术引入药物制备工艺、质量标准及稳定性研究,可克服由于活性成分不清楚带来的一些困难,拓宽了研究途径,提高了研究水平。 相似文献
36.
Carla Testorell Carlo Pruneri Luigi Ferini-Strambi Marco Zamperetti Carlo A. Altamura Salvatore Smirne Silvio R. Bareggi 《Human psychopharmacology》1993,8(6):423-428
Serum immunoglobulins and the activity of natural killer (NK) cells of 50 epileptic patients (eight with idiopathic generalized epilepsy and 42 with cryptogenic partial epilepsy) and 28 controls have been studied. The values of IgA, IgG and IgM were the same-in patients and controls. The NK activity in controls was linearly related to the effector-to-target ratio, but this linear relationship was not observed in epileptic patients. The cytotoxic activity of NK cells at the lowest effector-to-target ratio was significantly greater in patients than in controls. This increase was observed in each therapy group. Our results seem to confirm a disturbance of the immune system in epileptic patients and suggest that this modification of cellular immunity is not a drug effect but is related to the illness itself. 相似文献
37.
It is controversial whether gastrooesophageal reflux disease represents a spectrum disease from a nonerosive to a complicated one, or whether it is a categorial disease, i.e. it can be divided into three categories, such as nonerosive gastrooesophageal reflux disease, erosive gastrooesophageal reflux disease and Barrett's esophagus (BE) with little or no transition from one category to the other. This controversy might be of general interest, because it has some implications in the management of the patient. However, literature data concerning the natural history of gastrooesophageal reflux disease are very limited, and in particular very few papers have dealt with the issue of describing the natural history of patients with nonerosive gastrooesophageal reflux disease. Aim of the present review is to reassess these scanty data, and to try to demonstrate that progression from milder to more severe forms of gastrooesophageal reflux disease is possible and documented. 相似文献
38.
《Immunity》2020,52(6):1075-1087.e8
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39.
Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases. 相似文献
40.
Changes in activity of some mechanisms of specific and nonspecific immunity in vitamin B1 deficiency
A. D. Pletsityi 《Bulletin of experimental biology and medicine》1979,88(1):741-743
The effect of thiamine deficiency on the immune response and activity of certain mechanisms of natural immunity was studied in adult rats. Thiamine deficiency was simulated experimentally by a single injection of hydroxythiamine, a vitamin B1 antagonist. Administration of hydroxythiamine caused a marked decrease in complement activity, phagocytic activity of the peripheral blood leukocytes, bactericidal activity of the serum, and antibody production in response to immunization with sheep's red blood cells. Conversely, lysozyme activity increased. In vitamin B1 deficiency the intensity of incorporation of [14C]leucine into liver protein synthesis was reduced.Department of Pathological Physiology, N. I. Sechenov First Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR G. V. Vygodchikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 7, pp. 60–62, July, 1979. 相似文献