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991.
Role of Th1 and Th2 cytokines in regulating the liver injury induced by delayed-type hypersensitivity to picryl chloride 总被引:3,自引:0,他引:3
AIMS/BACKGROUND: We have previously reported that a new model of liver injury induced in mice by delayed-type hypersensitivity (DTH) to picryl chloride (PCl) mimicks the pathogenesis of human hepatitis. This liver injury is mediated by CD4+ T cells. The interaction between lymphocyte function associated antigen 1 (LFA-1) and intercellular adhesion molecule 1 (ICAM-1) is an essential process for hepatocyte (HC) damage. The present study was undertaken to reveal the role of Th1 and Th2-like cytokines in regulating the liver injury. METHODS: The kinetics of cytokine production were examined by ELISA and RT-PCR after the elicitation of liver injury for both serum protein and liver mRNA expression, respectively. A co-culture assay between liver nonparenchymal cells (NPC) and HC was conducted to evaluate the cytokine regulation on the cell-cell interaction. Expression of LFA-1 on NPC and ICAM-1 on HC were examined by FACScan and ELISA, respectively. RESULTS: Serum IL-2 and IFN-gamma showed a peak production at 6 and 12 h, while IL-5 and IL-4 reached their maximum levels at 18 and 24 h after induction of liver injury, respectively. Liver mRNA expression of IFN-gamma and IL-4 had a similar time course to their corresponding products. Both recombinant murine IFN-gamma and IL-2 triggered the hepatotoxicity of NPC or spleen cells at 0 h. In this case, an increased expression of both LFA-1 on NPC and ICAM-1 on HC was also observed. In contrast, IL-4 and IL-5 completely abolished the hepatotoxicity of NPC at 12 h without influencing the adhesion molecules. CONCLUSION: Th1 and Th2 may be involved in regulating liver injury. Th1/Th2 balance may critically contribute to the production of the liver injury or recovery from it. 相似文献
992.
J. Fu H. Ikegami Y. Kawaguchi T. Fujisawa Y. Kawabata Y. Hamada H. Ueda M. Shintani K. Nojima N. Babaya Q.-J. Shen Y. Uchigata T. Urakami Y. Omori K. Shima T. Ogihara 《Diabetologia》1998,41(2):228-232
Summary An insulin-dependent diabetes mellitus (IDDM)-susceptibility gene (IDDM13) has recently been mapped to a region of distal chromosome 2q, which is syntenic to the region of mouse chromosome 1 containing
a murine susceptibility gene for IDDM, Idd5. To determine the contribution of this region to IDDM disease susceptibility further and to narrow the region for positional
cloning of susceptibility genes, we have studied the association of distal chromosome 2q with IDDM in the genetically distinct
Japanese population. A 137 mobility unit (mu) allele at D2S137 locus was significantly associated with IDDM (odds ratio 1.92, p = 0.0016). Other markers, D2S301 and D2S143, located in the same region were not associated with IDDM, indicating that IDDM13 is in linkage disequilibrium with D2S137, but not with D2S301 or D2S143. The association of D2S137 with IDDM was observed in patients lacking one of two high risk HLA alleles, DQB1
*
0303 and DQB1
*
0401, but not in patients with either of these alleles. The frequency of high risk HLA alleles was significantly lower in patients
with the susceptible allele at D2S137, suggesting that IDDM13 contributes to IDDM susceptibility in subjects without high risk genotypes at IDDM1. Demonstration of allelic association of D2S137 with IDDM localizes IDDM13 in the close vicinity (< 2 centiMorgans) of D2S137, greatly facilitating fine structure mapping and positional cloning of IDDM13. [Diabetologia (1998) 41: 228–232]
Received: 27 March 1997 and in revised form: 3 October 1997 相似文献
993.
Zhang Q Arbuckle J Wessler SR 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(3):1160-1165
A 314-bp DNA element called Heartbreaker-hm1 (Hbr-hm1) was previously identified in the 3' untranslated region of a mutant allele of the maize disease resistance gene HM1. This element has structural features of miniature inverted-repeat transposable elements (MITEs) and is a member of a large family of approximately 4,000 copies in the maize genome. Unlike previously described MITEs, most members of the Hbr family display over 90% sequence identity. This, coupled with the insertion of an Hbr element into an allele of the HM1 gene, suggested that this family might have spread recently throughout the genome. Consistent with this view is the finding that Hbr insertion sites are remarkably polymorphic. Ten of ten loci containing Hbr elements were found to be polymorphic for the presence or absence of Hbr among a collection of maize inbred lines and teosinte strains. Despite the fact that over 80% of the maize genome contain moderate to highly repetitive DNA, we find that randomly chosen Hbr elements are predominantly in single or low copy regions. Furthermore, when used to query both the public and private databases of plant genes, over 50% of the sequences flanking these Hbr elements resulted in significant "hits." Taken together, these data indicate that the presence or absence of Hbr elements is a significant contributory factor to the high level of polymorphism associated with maize genic regions. 相似文献
994.
K A Monsur M S Hossain F Huq M M Rahaman M Q Haque 《The Journal of infectious diseases》1975,131(1):40-43
A controlled study of the efficacy of cytosine arabinoside in the treatment of patients with variola major was performed. Cytosine aravinoside was given intravenously at a dose approximating 3 mg/kg of body weight every 24 hr for up to seven days. All nine patients receiving cytosine arabinoside and four of the 11 patients receiving placebo died. In three of the patients receiving cytosine aravinoside, death occurred late in the illness at a time when the patient's lesions began to dry up, the patient's temperature became normal, and the patient's general condition appeared to improve. The virus could be isolated from the blood at day 7 from three of four patients treated with cytosine arabinoside as compared with zero of six control patients. Hematologic data showed a depression in the number of circulating granulocytes. It is possible that the drug lowered the resistance to infection either through direct suppression of granulocytes or through interference with other immune mechanisms. Cytosine arabinside administered in the doses used in this study is not effective in the treatment of variola major. 相似文献
995.
Rian Q. Landers-Ramos Nathan T. Jenkins Espen E. Spangenburg James M. Hagberg Steven J. Prior 《European journal of applied physiology》2014,114(7):1377-1384
Purpose
Endurance exercise training can ameliorate many cardiovascular and metabolic disorders and attenuate responses to inflammatory stimuli. The purpose of this study was to determine whether the angiogenic and pro-inflammatory cytokine response to acute endurance exercise differs between endurance-trained and sedentary young men.Methods
Ten endurance-trained and ten sedentary healthy young men performed 30 min of treadmill running at 75 % VO2max with blood sampling before and after exercise. Plasma concentrations of tumor necrosis factor (TNF)-alpha, interleukin (IL)-8, IL-6, vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), placental growth factor (PlGF), and soluble VEGF receptor-1 (sFlt-1) were measured by multiplex ELISA.Results
Acute exercise increased IL-6 by 165 % (P < 0.05), IL-8 by 32 % (P < 0.05), PlGF by ~16 % (P < 0.05), sFlt-1 by 36 % (P < 0.001), and tended to increase bFGF by ~25 % (P = 0.06) in main effects analyses. TNF-α and VEGF did not change significantly with exercise in either group. Contrary to our hypothesis, there were no significant differences in TNF-α, IL-6, VEGF, bFGF, PlGF, or sFlt-1 between groups before or after acute exercise; however, there was a tendency for IL-8 concentrations to be higher in endurance-trained subjects compared to sedentary subjects (P = 0.06).Conclusions
These results indicate that 30 min of treadmill running at 75 % VO2max produces a systemic angiogenic and inflammatory reaction, but endurance exercise training does not appear to significantly alter these responses in healthy young men. 相似文献996.
997.
998.
999.
High-quality evidence suggests that aspirin is a promising agent for cancer prevention and treatment. Direct inhibition of cyclooxygenase-2 (COX-2) pathway is generally thought to be the main mechanism by which aspirin inhibits cancer development. However, either pharmacological properties of aspirin or recent results of epidemiologic studies do not support that mechanism. To address this inconsistency, we hypothesize that antiplatelet effect of aspirin via inhibition of COX-1 may be one of potential mechanisms to inhibit carcinogenesis. Aberrant platelet activation will lead to promote hostility of tumor microenvironment by releasing an abundant array of angiogenesis regulators. 相似文献
1000.
Interleukin‐22 (IL‐22) and IL‐22‐producing T helper (Th) cells are involved in the pathogenesis of autoimmune diseases. However, the roles of IL‐22 and IL‐22‐producing T helper cells in systemic lupus erythematosus (SLE) remain unclear. Plasma levels of IL‐22 were measured in 41 patients with SLE (19 new‐onset and 22 relapsing patients) and 20 healthy controls by enzyme‐linked immunosorbent assay (ELISA). Meanwhile, the percentages of CD4+IFN‐γ+ (Th1), CD4+IL‐17+ (Th17) and CD4+IFN‐γ?IL‐17? IL‐22+ (Th22) cells in peripheral lymphocytes were determined by flow cytometry, and plasma IL‐22 autoantibodies were detected by ELISA in 19 new‐onset SLE patients and 20 healthy controls. Plasma IL‐22 levels in new‐onset SLE patients were significantly decreased compared with relapsing SLE patients and healthy controls. After treatment with prednisone and hydroxychloroquine, the levels of plasma IL‐22 in new‐onset SLE patients were obviously increased but still lower than healthy controls. There was a positive correlation between plasma IL‐22 levels and the percentages of Th22 cells, but not Th1 and Th17 cells. Moreover, plasma IL‐22 levels as well as peripheral Th17 and Th22 cells correlated with SLE disease activity index (SLEDAI) scores and erythrocyte sedimentation rate (ESR). High frequencies of plasma IL‐22 autoantibodies were detected in new‐onset SLE patients. However, IL‐22 levels did not correlate with IL‐22 autoantibody. Decreased plasma IL‐22 levels and correlation with Th22 cells may be distinct features in new‐onset SLE. Moreover, IL‐22 and Th22 cell correlated with SLE disease activity. 相似文献