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排序方式: 共有5126条查询结果,搜索用时 12 毫秒
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A Flowcytometry Study of CD55 and CD59 Expression on Erythrocytes in Rheumatoid Arthritis Patients 下载免费PDF全文
Abbas Ali PourazarAlireza AndalibFarzad QreizyHadi KarimzadehAhmad Ghavami-NejadBehshad Pournasr-Khakbaz 《Iranian journal of immunology : IJI》2005,2(2):91-96
Background: Inappropriate activation or blockage of the inhibition of complement system could cause tissue damages in autoimmune diseases particularly rheumatoid arthritis (RA). Defect in complement component regulation may cause damages to tissues, on the other hand, or the damaged tissue might affect the unnecessary activation of complement components. Objective: To investigate the expression of CD55 and CD 59 complement regulatory proteins in RA patients. Subjects and Methods: Fifty proved rheumatoid arthritis patients participated in this study and their blood were collected for investigations. CD55 and CD59 molecules expression on the erythrocytes was assayed using primary monoclonal antibody and secondary FITC conjugated Ab, then the prepared samples were run with a FACSCalibur flowcytometer (Becton-Dickinson) and the obtained data was analyzed using a Cell Quest software package. To evaluate the complement function, CH50 was performed using patient sera. All experiments were done with a matched healthy volunteer group. Results: The mean fluorescence intensity for CD55 was 27.6 ± 13.4 arbitrary unit for patients and 68.5 ± 10.5 for healthy group. CD59 mean fluorescence intensity was 314 ± 83 in patient group and 508 ± 56 in healthy volunteers. In addition, there was a significant difference between CH50 in patients (54.5 ± 15.5) and in healthy group (110 ± 20). A significant correlation between CD55 and CD59 expansion on the patient erythrocytes was found (P = 0.00, r = 0.576). No association was found between CD59, or CD55 with CH50 (P > 0.05). Conclusion: The expression of CD55 and CD59 is down-regulated on erythrocytes of patients with RA. Change in expression of regulatory complement components in RA may be a useful key for the assessment of disease progression or in patients' follow-up. 相似文献
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Genotoxic potential of Polycyclic Aromatic Hydrocarbons-coated onto airborne Particulate Matter (PM 2.5) in human lung epithelial A549 cells 总被引:1,自引:0,他引:1
Billet S Abbas I Le Goff J Verdin A André V Lafargue PE Hachimi A Cazier F Sichel F Shirali P Garçon G 《Cancer letters》2008,270(1):144-155
To improve the knowledge of the underlying mechanisms of action involved in air pollution Particulate Matter (PM)-induced toxicity in human lungs, with a particular interest of the crucial role played by coated-organic chemicals, we were interested in the metabolic activation of Polycyclic Aromatic Hydrocarbons (PAH)-coated onto air pollution PM, and, thereafter, the formation of PAH-DNA adducts in a human lung epithelial cell model (A549 cell line). Cells were exposed to Dunkerque city's PM(2.5) at its Lethal Concentrations at 10% and 50% (i.e. LC(10)=23.72 microg/mL or 6.33 microg/cm2, and LC(50)=118.60 microg/mL or 31.63 microg/cm2), and the study of Cytochrome P450 (CYP) 1A1 gene expression (i.e. RT-PCR) and protein activity (i.e. EROD activity), and the formation of PAH-DNA adducts (i.e. 32P-postlabeling), were investigated after 24, 48, and/or 72 h. PAH, PolyChlorinated Dibenzo-p-Dioxins and -Furans (PCDD/F), Dioxin-Like PolyChlorinated Biphenyls (DLPCB), and PolyChlorinated Biphenyls (PCB)-coated onto collected PM were determined (i.e. GC/MS and HRGC/HRMS, respectively), Negative (i.e. TiO2 or desorbed PM, dPM; EqLC10=19.42 microg/mL or 5.18 microg/cm2, and EqLC50=97.13 microg/mL or 25.90 microg/cm2), and positive (i.e. benzo(a)pyrene; 1 microM) controls were included in the experimental design. Statistically significant increases of CYP1A1 gene expression and protein activity were observed in A549 cells, 24, 48 and 72 h after their exposure to dPM, suggesting thereby that the employed outgassing method was not efficient enough to remove total PAH. Both the CYP1A1 gene expression and EROD activity were highly induced 24, 48 and 72 h after cell exposure to PM. However, only very low levels of PAH-DNA adducts, also not reliably quantifiable, were reported 72 h after cell exposure to dPM, and, particularly, PM. The relatively low levels of PAH together with the presence of PCDD/F, DLPCB, and PCB-coated onto Dunkerque City's PM 2.5 could notably contribute to explain the borderline detection of PAH-DNA adducts in dPM and/or PM-exposed A549 cells. Hence, remaining very low doses of PAH in dPM or relatively low doses of PAH-coated onto PM were involved in enzymatic induction, a key feature in PAH-toxicity, but failed to show a clear genotoxicity in this in vitro study. We also concluded that, in the human lung epithelial cell model we used, and in the experimental conditions we chose, bulky-DNA adduct formation was apparently not a major factor involved in the Dunkerque City's PM 2.5-induced toxicity. 相似文献
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Effects of in-season short-term plyometric training on jumping and agility performance of basketball players 总被引:1,自引:0,他引:1
Abbas Asadi 《Sport Sciences for Health》2013,9(3):133-137
The purpose of this investigation was to examine the effects of in-season plyometric training program on power and agility performance in young male basketball players. Twenty intermediate basketball players (age 20.1 ± 1.3 years; height 181.1 ± 8.5 cm; body mass 78.8 ± 5 kg) from Division I province team volunteered to participate in this study and were randomly divided into two groups: plyometric training (PL; n = 10) and control group (CG; n = 10). Plyometric training took place twice weekly for 6 weeks including three sets of 15 repetitions of depth jump (from 45-cm box height), vertical jump, and standing long jump, in addition to regular basketball practice of the team. Vertical jump (VJ), standing long jump (SLJ), 4 × 9-m shuttle run, agility t test (ATT), and Illinois Agility Test (IAT) were measured at pre- and post-training. The PL group showed significant improvement (P < 0.05) in VJ (10.21 ± 2.72 cm), SLJ (21.15 ± 8.10 cm), 4 × 9-m shuttle run (0.62 ± 0.28 s), ATT (1.16 ± 0.57 s), and IAT (1.17 ± 0.65 s) after a 6-week training period and compared to CG. It can be concluded that a 6-week in-season plyometric training program has positive effects for improving power and agility performance in young male basketball players and this study provides support for coaches and basketball players who use this training method during competitive phase. 相似文献