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Miodrag ?oli? Vesna Ili? Milo? D. Pavlovi? Takuya Tamatani Masayuki Miyasaka 《Clinical & developmental immunology》1996,5(1):37-51
The effects of monoclonal antibodies (mAbs) to cell-surface molecules, divalent cations,
and various cell-signaling and metabolic inhibitors on the binding of thymocytes to rat
thymic dendritic cells (TDC) were studied using a rosette assay. It was found that TDC/thymocyte adhesion was stronger and faster at 37°C than at 4°C. Flow cytometric analysis demonstrated that bound thymocytes were predominantly CD4+CD8+ and CD4+CD8-, but in comparison to the phenotype of whole thymocytes, they were enriched in the mature
TCRαβhi subset. The binding of thymocytes to TDC at 37°C was almost completely
dependent on Ca2+ and Mg2+ and partly on an intact cytoskeleton and calmodulin-dependent
protein kinase. The adhesion was independent of new protein synthesis and the activities of protein kinases A and C, tyrosine kinases, as well as phosphotyrosine protein phosphatases. The TDC/thymocyte adhesion at 37°C was partly blocked by anti-LFA-1
(WT.1), anti-CD18 (WT.3), and anti-ICAM-1 (1A29) mAb. MAbs to class II MHC (OX-3 and OX-6), CD4 (W3/25), CD8 (OX-8), and αβTCR (R73) stimulated the adhesion via an LFA-1-dependent pathway, whereas an anti-CD45 mAb (G3C5) stimulated the rosette formation
independently of LFA-1. MAbs to CD2 (OX-34), CD11b (ED7), CD11b/c (OX-42), and class I MHC (OX-18) were without significant effects on the adhesion process. 相似文献
6.
Janać B Pesić V Peković S Rakić L Stojiljković M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,165(3):402-406
The time-course of changes of basal and amphetamine (AMPH)-induced locomotor and stereotypic activities in adult male Wistar rats after a single ribavirin injection was studied. In the first set of experiments, 10, 20 or 30 mg ribavirin/kg body weight (b.w.) were injected i.p. to rats and their basal motor activities were recorded every 10 min for 2 h and compared with those of saline-treated controls. In the second set of experiments, the animals were pretreated with ribavirin and 20 min later i.p. injected with AMPH (1.5 mg/kg b.w.). The controls received AMPH 20 min after the saline injection. Motor activity was recorded after the first injection and until 120 min after AMPH administration. Ribavirin did not significantly affect the time-course of either basal locomotor or stereotypic activities. Pretreatment with any of the applied ribavirin doses decreased the AMPH-induced hyperlocomotor response. However, the most pronounced effect was observed with ribavirin doses of 20 mg/kg and 30 mg/kg when administered during the first 10 min and 30 min after the AMPH injection respectively. In contrast, the stereotypic activities of these animals were only slightly changed. These results indicate a different susceptibility of regions in the basal ganglia to ribavirin. 相似文献
7.
Djordjevic V Jankovic G Suvajdzic N Marisavljevic D Pantic M Bogdanovic A Sefer D Dencic M Colovic M 《Cancer Genetics and Cytogenetics》2005,160(1):89-93
Duplication of the long arm of chromosome 1 (1q) is widely reported in human neoplasia, including the myelodysplastic syndromes (MDS). So far, it has not been described as a single aberration in the chronic myelomonocytic leukemia (CMML), a subtype of MDS. Rather, trisomy 1q was always a part of complex chromosome changes affecting the subtypes of MDS other than CMML. We report on a patient with CMML with an unbalanced translocation of the entire 1q onto the short arm of chromosome 14 as a sole cytogenetic abnormality. Fluorescence in situ hybridization (FISH) analysis with an alpha-satellite probe for the paracentric region of the long arm of chromosome 1 confirmed the presence of trisomy 1q in a derivative chromosome, der(14)t(1;14)(q12;p11). The discrepant results between the metaphase cytogenetics (100% abnormal) and interphase cytogenetic (71% nuclei with 3 signals) suggest that trisomy 1q, even in the absence of additional cytogenetic changes, has a sufficient leukemogenic potential to confer a proliferative advantage on hematopoietic cells committed to monocyte stemline both in vitro and in vivo. The literature data on partial and complete trisomy 1q in CMML is reviewed. 相似文献
8.
In vitro studies of delayed hypersensitivity: inhibition of macrophage spreading in rats sensitive to tuberculin and diphtheria toxoid
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Wistar rats were sensitized by footpad injection of BCG in adjuvant, or Mycobacterium butyricum in adjuvant, or diphtheria toxoid in Freund's incomplete adjuvant. It was found that the cell population of the peritoneal washings contained approximately 57 per cent macrophages, 22 per cent lymphocytes, 11 per cent granulocytes and 8 per cent mast cells. The lymphocyte count was significantly reduced and the granulocyte count increased after sensitization. The animals sensitized to M. butyricum exhibited delayed skin reactivity to tuberculin and the spreading of macrophages in vitro was significantly inhibited with the same antigen. On the contrary, the spreading of macrophages obtained from animals sensitized to BCG was not inhibited by tuberculin and there was no cutaneous reactivity. Spreading of macrophages obtained from rats sensitized by diphtheria toxoid was significantly inhibited in the presence of diphtheria toxoid, but not in the presence of tuberculin. These animals displayed delayed cutaneous hypersensitivity to diphtheria toxoid. Spreading of macrophages from normal rats was unaffected by serum antibodies. This was true either when the peritoneal cells were treated with antiserum prior to contact with antigen, or when the antigen—antibody reaction took place in the chamber containing the macrophages ready to spread. These results indicate that the technique of macrophage spreading inhibition is able to detect specifically hypersensitivity of delayed type and offers a convenient method for the in vitro study of delayed hypersensitivity. 相似文献
9.
Vesna Čapkun Davor Eterović 《European journal of nuclear medicine and molecular imaging》1985,11(4):120-122
Radionuclide-angiography (RNA_ left-to-right intracardiac-shunt quantification algorithms, based on the part-by-part fit technique and the use of a so-called gamma variate model function (GVF), were tested via simulation analysis using data obtained from normal subjects. A good bolus of radioindicator was obtained by administering it directly into the vena subclavia. Normal subjects were defined as those having pulmonary histograms (PH) with no visible distortion caused by a shunt. Pure, non-superimposed data on the downslope of the PH curves, which are lost in presence of a shunt, proved to be appropriate reference values for testing the accuracy of results of standard shunt quantification algorithms. A generalized four-parameter GVF was introduced in order to extend the flexibility of the model function. The use of the three-parametric GVF to reconstruct the downslope of the PH curve out of the upslope data proved to be inadequate. This reveals an evident source of error in algorithms that calculate the shunt contribution by fitting GVF parameters to so-called difference-curve data. It is concluded that the inherent restricted statistical weight of RNA data prevents accurate results being obtained from standard RNA-shunt-assessment algorithms. 相似文献
10.
Vesna D. Garovic Michael J. Joyner† Niki M. Dietz† Eric Boerwinkle‡ Stephen T. Turner 《The Journal of physiology》2003,546(2):583-589
Polymorphisms in the gene encoding the β2 -adrenoceptor have been associated with interindividual differences in blood pressure and the diagnosis of hypertension. A common polymorphism resulting in a change from arginine to glycine at amino acid 16 (Arg16 → Gly) enhances agonist-promoted downregulation of receptor expression in vitro . It is unknown whether genotype-dependent differences in nitric oxide generation contribute to differences in vasodilator responses to β2 -agonists in vivo . To address this question, venous occlusion plethysmography was used to measure forearm blood flow responses to graded brachial artery infusions of the β-agonist isoproterenol in 41 healthy normotensive Caucasian adults (mean age (± s.d .) = 29 ± 6 years), who were either Arg16 ( n = 18) or Gly16 ( n = 23) homozygotes. Compared to Arg16 homozygotes, Gly16 homozygotes demonstrated significantly greater blood flow responses to isoproterenol ( P = 0.02). After inhibition of nitric oxide synthase by N γ -monomethyl- l -arginine, blood flow responses did not differ significantly between genotype groups ( P = 0.27). Consequently, effects of the Arg16 → Gly polymorphism on forearm blood flow responses to isoproterenol appear to be dependent on differences in endothelial generation of nitric oxide. In contrast to previous reports based on systemic infusions of β2 -agonists, our findings indicate that regional blood flow responses to locally infused isoproterenol are significantly greater in Gly16 than in Arg16 homozygotes. 相似文献