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71.
《Renal failure》2013,35(10):1418-1428
AbstractObjective: The effects of inhibition of monocyte chemoattractant protein-1 (MCP-1) on a rat model of mesangial proliferative glomerulonephritis (MsPGN) were evaluated. Methods: The anti-Thy-1 MsPGN model was developed by intravenously injecting anti-Thy-1 monoclonal antibodies into rats, followed by an injection of mesangial cells transfected with antisense MCP-1 into the renal artery. Exogenous cells were detected by in situ hybridization. Rats (40 total) were randomly divided into five groups: SO (sham operation), TG (Thy-1 glomerulonephritis model), MC (non-transfected normal rat mesangial cell), BC (pLXSN empty vector or blank control), and AM (antisense MCP-1 transfection) groups. Effects of exogenous MCP-1 on urinary protein excretion rate, biochemical parameters, and pathological changes were evaluated. Expression of MCP-1 and transforming growth factor-β1 (TGF-β1) were detected by immunohistochemistry. mRNA expression of MCP-1, TGF-β1, and CC chemokine receptor 2 (CCR2) were detected by RT-PCR. Results: Exogenous MCP-1 cDNA was successfully transfected into mesangial cells. Exogenous mesangial cells were detected in glomeruli by in situ hybridization. Glomerular mesangial cell proliferation, 24-h urinary protein excretion rate, mRNA expression of MCP-1, TGF-β1, and CCR2, and protein expression of MCP-1 all decreased in the AM group as compared to the control group (p?<?0.05), but there was no significant difference in the expression level of TGF-β1 protein. Conclusions: (1) Mesangial cells can be used as a vector to transfect exogenous genes into kidneys; (2) antisense MCP-1 decreases mesangial cell proliferation and pathological injury in MsPGN model rats by decreasing expression of MCP-1 and CCR2; and (3) antisense MCP-1 suppressed mesangial cell proliferation and matrix accumulation in anti-Thy-1 MsPGN model rats, which did not entirely depend on TGF-β1. 相似文献
72.
目的探讨腺病毒介导NK4基因联合单核细胞趋化蛋白1(MCP-1)基因在胰腺癌中的共表达及对胰腺癌细胞的影响。方法利用重组腺病毒AD-MCP-1、AD-NK4分别单独和联合感染胰腺癌细胞株SW1990,荧光定量RT-PCR和酶联免疫吸附剂测定(ELISA)法检测NK4和MCP-1的表达情况并观察其对胰腺癌细胞和血管内皮细胞生长的影响。结果当感染复数(MOI)为60efu/细胞时,SW1990细胞的感染效率接近100%,相应基因mRNA表达在AD-MCP-1组、AD-NK4组和联合组中感染后第5天达到最高,但是联合组中的MCP-1和NK4的表达水平要低于单一感染(P〈0.05)。相对于其他各组,联合感染后胰腺癌细胞的相对生长率没有明显的改变。AD-NK4组和联合组的上清均有抑制血管内皮细胞生长的作用,但两组比较差异无统计学意义。结论腺病毒介导NK4联合MCP-1基因感染胰腺癌SW1990细胞没有抑制作用,但NK4能够抑制血管内皮细胞的生长从而发挥抑癌作用。 相似文献
73.
HIV-1 evolution in the envelope gene (env) was analyzed in four asymptomatic antiretroviral therapy na?ve patients with typical and slow disease progression rates. In typical progressors, viral populations were monophyletic and two distinct evolutionary patterns were observed. In one patient, HIV-1 evolution displayed a strong temporal structure similar to the consistent pattern previously described. In the other, viral evolution displayed a lack of temporal structure with no increase in genetic heterogeneity and divergence over time. In slow progressors, several clades were observed in viral populations. However, analysis within the major sub-population revealed the same two evolutionary patterns described for typical progressors. Synonymous and non-synonymous substitution rate analyses indicated that positive selection was the major force driving HIV-1 evolution in viral populations with temporal structure, while evolution in viral populations with an atemporal structure was dominated by genetic drift and purifying selection. These results support the existence of distinct patterns of env evolution in untreated HIV-1-infected patients. 相似文献
74.
Leukocyte trafficking through the microcirculation and into tissues is central in angiogenesis, inflammation, and the immune
response. Although the literature is rich with mechanistic detail describing molecular mediators of these processes, integration
of signaling events and cell behaviors within a unified spatial and temporal framework at the multi-cell tissue-level is needed
to achieve a fuller understanding. We have developed a novel computational framework that combines agent-based modeling (ABM)
with a network flow analysis to study monocyte homing. A microvascular network architecture derived from mouse muscle was
incorporated into the ABM. Each individual cell was represented by an individual agent in the simulation. The network flow
model calculates hemodynamic parameters (blood flow rates, fluid shear stress, and hydrostatic pressures) throughout the simulated
microvascular network. These are incorporated into the ABM to affect monocyte transit through the network and chemokine/cytokine
concentrations. In turn, simulated monocytes respond to their local mechanical and biochemical environments and make behavioral
decisions based on a rule set derived from independent literature. Simulated cell behaviors give rise to emergent leukocyte
rolling, adhesion, and extravasation. Molecular knockout simulations were performed to validate the model, and predictions
of monocyte adhesion, rolling, and extravasation show good agreement with the independently published corresponding mouse
studies.
Alexander M. Bailey and Bryan C. Thorne contributed equally to this work. 相似文献
75.
目的 研究高海拔地区缺血性卒中患者单核细胞/HDL-C比值(monocyte/HDL-C ratio,MHR)与颅内动脉粥样硬化性狭窄(intracranial atherosclerotic stenosis,ICSA)程度的相关性。
方法 回顾性连续纳入2017年6月-2021年6月在青海省人民医院住院治疗的高海拔地区(海拔2260~4080?m)的急性缺血性卒中患者,依据DSA上脑血管狭窄程度(以狭窄最严重的动脉为准)分为无狭窄组、轻度狭窄(狭窄率≤50%)组、中度狭窄(狭窄率50%~70%)组、重度狭窄(狭窄率≥70%)组及闭塞(100%)组。比较5组患者的临床资料、实验室检查指标和MHR,并采用logistic回归模型计算不同程度血管狭窄的独立危险因素。
结果 共纳入349例患者,其中无狭窄组69例、轻度狭窄组78例、中度狭窄组41例、重度狭窄组84例、闭塞组77例。5组中年龄、性别分布、吸烟、饮酒、高血压、糖尿病比例方面差异均有统计学意义,实验室检查中白细胞、单核细胞、中性粒细胞、血小板计数以及血红蛋白、HDL-C水平和MHR差异也有统计学意义。多因素logistic回归分析显示,相对于无动脉狭窄,高龄为脑血管轻度狭窄(OR?1.061,95%CI?1.027~1.097,P<0.001),中度狭窄(OR?1.057,95%CI?1.017~1.099,P=0.005),重度狭窄(OR?1.096,95%CI?1.057~1.137,P<0.001),闭塞(OR?1.036,95%CI?1.001~1.072,P=0.046)的独立危险因素;相对于无动脉狭窄,高MHR为轻度狭窄(OR?1.041,95%CI?1.009~1.074,P=0.011),中度狭窄(OR?1.082,95%CI?1.045~1.119,P<0.001),重度狭窄(OR?1.096,95%CI?1.062~1.131,P<0.001),闭塞(OR?1.101,95%CI?1.067~1.136,P<0.001)的独立危险因素;相对于无动脉狭窄,单核细胞计数升高是中度狭窄(OR?1.684,95%CI?1.569~2.725,P=0.027)、重度狭窄(OR?3.529,95%CI?1.541~5.766,P=0.002 )和闭塞(OR?5.446,95%CI?4.453~6.917,P=0.002)的独立危险因素。
结论 高龄、高MHR和单核细胞计数升高在高海拔地区对急性缺血性卒中患者的脑动脉粥样硬化性狭窄程度具有一定预测价值。 相似文献
76.
目的:观察补肾养精汤和活血汤周期疗法对多囊卵巢综合征患者血清激素、内生殖器形态的影响。方法:选取多囊卵巢综合征患者98例,按随机数字表法分为对照组和观察组各49例。对照组给予克罗米芬治疗,观察组在对照组基础上加用补肾养精汤和活血汤周期疗法治疗。比较2组治疗后的临床疗效,检测治疗前后性激素水平、卵巢体积和子宫内膜厚度。结果:观察组总有效率为89.80%,高于对照组73.47%,差异有统计学意义(P<0.05)。治疗前,2组卵巢体积、子宫内膜厚度比较,差异无统计学意义(P>0.05)。治疗后,2组卵巢体积较治疗前降低,子宫内膜厚度较治疗前升高;且观察组卵巢体积低于对照组,子宫内膜厚度高于对照组;差异均有统计学意义(P<0.05)。治疗前,2组单核细胞趋化蛋白-1 (MCP-1)、热休克蛋白70(HSP70)水平比较,差异无统计学意义(P>0.05)。治疗后,2组MCP-1、HSP70水平较治疗前降低,且观察组MCP-1、HSP70水平低于对照组(P<0.05)。治疗前,2组血清激素水平比较,差异无统计学意义(P>0.05)。治疗后,2组促卵泡激素(FSH)、雌二醇(E2)较治疗前升高,促黄体激素(LH)、睾酮(T)较治疗前降低;且观察组FSH、E2高于对照组,LH、T低于对照组;差异均有统计学意义(P<0.05)。结论:补肾养精汤和活血汤周期疗法可调节多囊卵巢综合征患者血清相关因子水平,降低MCP-1、HSP70的表达,改善内生殖器形态。 相似文献
77.
Saniabadi AR Hanai H Takeuchi K Umemura K Nakashima M Adachi T Shima C Bjarnason I Lofberg R 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2003,7(1):48-59
Apheresis has been recognized both economically and therapeutically as a novel approach for the treatment of inflammatory diseases, and certain others, which respond poorly to drug therapy. This report is about Adacolumn, an adsorptive carrier based granulocyte and monocyte apheresis device with a volume of 335 mL, filled with about 220 g of cellulose acetate beads of 2 mm diameter as the column adsorptive carriers. Pre- and post-column leukocyte counts have shown that the carriers adsorb about 65% of granulocytes, 55% of monocytes and 2% of lymphocytes from the blood in the column. Additionally, after apheresis, there is a marked decrease in inflammatory cytokines (TNF-alpha, IL-1beta, IL-6 and IL-8) produced by blood leukocytes, together with down-modulation of L-selectin and the chemokine receptor CXCR3. Adacolumn has been used to treat patients with rheumatoid arthritis, ulcerative colitis and HIV infection. Typical apheresis sessions have been 4-10, at a frequency of one or two sessions per week. Treatment of patients with Adacolumn has been associated with very promising efficacy and safety data. Accordingly, in Japan, Adacolumn has been approved by the Ministry of Health for the treatment of ulcerative colitia. Furthermore, Adacolumn met the required quality and safety standards for medical devices and received an EC certification (CE-mark) from TUV in 1999. However, although Adacolumn carriers are very efficient in depleting excess and activated granulocytes and monocytes/macrophages, the clinical efficacy associated with Adacolumn apheresis cannot be fully explained on the basis of reducing granulocytes and monocytes per se. Hence, a long lasting effect on inflammatory cytokine generation, chemokine activities or immunomodulation is likely, but the precise mechanisms involved are not fully understood yet. 相似文献
78.
The present study was performed to examine whether the expression of CD64 Fc gamma receptor type I (FcgammaRI) on both neutrophils and monocytes can be modulated by multiple daily administrations of granulocyte colony-stimulating factor (G-CSF) to patients with non-Hodgkin's lymphoma in neutropenia caused by CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) chemotherapy. The expression of CD64 was determined by flow cytometric analysis at the following time points: before chemotherapy, at the nadir of the neutrophil count, at the fifth day after the start of G-CSF administration, and at more than 8 days after the start of G-CSF administration. CD64 expression was enhanced in patients given G-CSF during CHOP treatment, whereas CD64 expression remained unchanged in patients not given G-CSF CD64 expression levels on both neutrophils and monocytes were significantly up-regulated by the daily administration of G-CSF and reached peak levels at day 5 (P = .0007). Thereafter, expression on both cell types remained at almost the same levels as on day 5 for the rest of the treatment course, even though G-CSF therapy continued for 3 to 5 more days. Interestingly, CD64 expression on monocytes was already increased significantly (P = .0001) at the nadir of the neutrophil count relative to the baseline before chemotherapy and then was additionally up-regulated by day 5 after the start of G-CSF injections (P = .019). In antibody-dependent cellular cytotoxicity assays, we found that rituximab-mediated cell lysis was significantly enhanced at day 5 after the start of G-CSF treatment (P = .01). In conclusion, this study shows that multiple doses of G-CSF administered to lymphoma patients with neutropenia due to CHOP chemotherapy can enhance CD64 expression on both neutrophils and monocytes. Peak CD64 levels are reached at day 5 of G-CSF treatment, resulting in an activation of the rituximab-mediated antitumor ability of these effector cells. This finding may be useful in determining the optimal timing of administration for an antibody such as rituximab in a chemotherapeutic strategy designed to exert a maximal effect against tumor cells. 相似文献
79.
血小板源生长因子对大鼠血管平滑肌细胞表达血管细胞粘附分子1的影响 总被引:1,自引:0,他引:1
目的本实验研究血小板源生长因子对血管平滑肌细胞表达血管细胞粘附分子1的影响以及对血管平滑肌细胞与单核细胞粘附的作用。方法利用基因芯片和RT-PCR技术检测鼠主动脉血管平滑肌细胞经血小板源生长因子处理0min、20min、6h后血管平滑肌细胞表达血管细胞粘附分子1的mRNA表达变化;细胞粘附实验观察血管平滑肌细胞经血小板源生长因子分别处理0min、20min、6h后与单核细胞粘附情况。结果血小板源生长因子对鼠血管平滑肌细胞表达血管细胞粘附分子1的表达有显著的诱导作用,其诱导作用在20min即已出现(P<0.05),6h时明显增强(P<0.01)。细胞粘附实验显示随着血小板源生长因子的作用时间的延长,血管平滑肌细胞与单核细胞的粘附率增高,血小板源生长因子处理20min和6h后粘附率是对照组的1.92倍和3.04倍(P<0.05)。结论血小板源生长因子明显诱导血管平滑肌细胞中血管平滑肌细胞表达血管细胞粘附分子1的表达,促进血管平滑肌细胞与单核细胞的粘附,从而参与了损伤早期,白细胞向内膜下迁移的炎症反应。 相似文献
80.
目的探讨单核细胞趋化蛋白-1(monocyte chemotactic protein-1,MCP-1)及脂蛋白(a)[lipoprotein(a),LP(a)]与梅尼埃病的关系。方法选取30只健康SD大鼠,分成正常组、对照组及实验组,每组10只,实验组腹腔注射醋酸去氨加压素(4μg·kg^-1·d^-1连续注射7 d后改为6μg·kg^-1·d^-1连续注射3 d)行膜迷路积水造模,对照组腹腔注射等量生理盐水,正常组不作处理,停药7 d后对三组动物行ABR检测,取耳蜗中阶横截面积(SM)/(中阶+前庭阶横截面积)(SM+SV)比值评价膜迷路积水情况。造模成功后通过免疫组化染色检测耳蜗组织中MCP-1的表达,通过酶联免疫吸附实验(ELISA)法检测血清中LP(a)的水平,对LP(a)水平与内耳积水程度及大鼠ABR各指标进行相关性分析。结果实验组波Ⅱ阈值升高、波Ⅱ、Ⅴ潜伏期及Ⅲ-Ⅴ波间期较正常组和对照组均延长,差异有统计学意义(P<0.05)。实验组、对照组、正常组SM/(SM+SV)比值分别为0.45±0.04、0.34±0.02、0.35±0.01,前者显著大于后两者(P<0.05)。实验组MCP-1在耳蜗螺旋器、血管纹螺旋韧带及神经节细胞组织表达明显,前庭膜上也有表达,其它两组无表达。实验组、对照组、正常组LP(a)水平分别为4.07±0.20、1.36±0.12、1.38±0.14 mg/L,前者显著高于后两者(P<0.001),LP(a)表达水平与膜迷路积水程度及ABR各指标间均呈正相关(P<0.001)。结论膜迷路积水模型大鼠耳蜗组织中MCP-1表达明显,血清LP(a)水平明显升高,且LP(a)水平与膜迷路积水程度及大鼠听力下降呈正相关,提示MCP-1和LP(a)可能与梅尼埃病的发生有关。 相似文献