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目的 探讨白细胞介素8(IL-8)对高糖诱导人脂肪间充质干细胞(hAdMSC)损伤的保护作用。方法含250 mmol/L葡萄糖的培养基建立细胞高糖模型;P65质粒转染人IL-8基因到hAdMSC为IL-8转染组,仅转染P65质粒者为P65对照组,在IL-8转染组中添加PD98059为Erk抑制剂组。利用MTT细胞增殖实验、ELISA或流式细胞技术检测各组hAdMSC增殖的光密度值(OD值)、Caspase-3、Erk或VEGF等蛋白的表达。结果 与P65对照组比较,IL-8转染组hAdMSC增殖OD值明显升高,Caspase-3蛋白表达下降(P <0.01);IL-8转染组Erk蛋白活性和VEGF蛋白含量明显高于P65对照组(P <0.01);但与IL-8转染组比较,Erk抑制剂组hAdMSC增殖的OD值降低,Caspase-3蛋白表达升高(P <0.01)。结论 IL-8在高糖环境下,通过Erk通路,发挥对hAdMSC的保护作用。
相似文献104.
A paracrine role for chemoattractant receptor-homologous molecule expressed on T helper type 2 cells (CRTH2) in mediating chemotactic activation of CRTH2+ CD4+ T helper type 2 lymphocytes 下载免费PDF全文
Activation of human CRTH2(+) CD4(+) T helper type 2 (Th2) cells with anti-CD3/anti-CD28 led to time-dependent production of prostaglandin D(2) (PGD(2)) which peaked at 8 hr. The production of PGD(2) was completely inhibited by cotreatment with the cyclo-oxygenase inhibitor diclofenac (10 microm) but was not affected by cotreatment with ramatroban, a dual antagonist of both the thromboxane-like prostanoid (TP) receptor and the chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2). Supernatants from activated CRTH2(+) CD4(+) Th2 cells caused a concentration-dependent increase in the migration of naive CRTH2(+) CD4(+) Th2 cells compared to supernatants from unstimulated CRTH2(+) CD4(+) Th2 cells. The level of chemotactic activity peaked at 8 hr after activation, corresponding to the peak levels of PGD(2), but production of chemotactic activity was only partially inhibited by the cyclo-oxygenase inhibitor diclofenac. In contrast, ramatroban completely inhibited the chemotactic responses of naive Th2 cells to supernatants from activated CRTH2(+) CD4(+) Th2 cells collected up to 8 hr after activation, although supernatants collected 24 hr after activation were less sensitive to inhibition by ramatroban. The selective TP antagonist SQ29548 did not inhibit migration of Th2 cells, implicating CRTH2 in this response. These data suggest that CRTH2 plays an important paracrine role in mediating chemotactic activation of Th2 cells. Interestingly, although PGD(2) is produced from Th2 cells and contributes to this paracrine activation, it appears that additional CRTH2 agonist factors are also produced by activated Th2 cells and the production of these factors occurs independently of the cyclo-oxygenase pathway of the arachidonic acid metabolism. 相似文献
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Molokova OA Kecherukov AI Aliev FSh Chernov IA Bychkov VG Kononov VP 《Bulletin of experimental biology and medicine》2007,143(6):767-770
Morphological changes in the wall of the large intestine were studied after its manual suturing by a double-row interrupted
suture with modern suture threads. Light and scanning electron microscopy showed “fuse properties” and “sawing effect” of
polyfilament twisted threads (e.g. vicryl). Monofilament threads were free from these drawbacks and therefore were preferable. Metal elastic threads on the
basis of titanium-nickelide alloys caused no inflammatory changes in tissues.
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Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 143, No. 6, pp. 714–717, June, 2007 相似文献
107.
Dushkin MI Khoshchenko OM Posokhova EN Schvarts YSh 《Bulletin of experimental biology and medicine》2007,144(5):713-716
We studied the effect of agonists of peroxisome proliferator-activated receptors α and γ and retinoid X receptors on the concentration
and synthesis of lipids in macrophages of C57Bl/6 mice with inflammation induced by intraperitoneal injection of zymosan.
We revealed a significant increase in [1-14C]oleate incorporation into cholesterol esters and triglycerides, increase in the content of free cholesterol, cholesterol
esters, and triglycerides, and formation of oil red-stained lipid inclusions in peritoneal macrophages 24 h after administration
of zymosan in a dose of 50 mg/kg. Treatment with agonists of retinoid X receptors and peroxisome proliferator-activated receptors
α and γ 30 min before and 12 h after zymosan injection decreased the synthesis of triglycerides and cholesterol esters, reduced
the content of free cholesterol, cholesterol esters, and triglycerides in macrophages, and prevented the formation of cytoplasmic
lipid inclusions in macrophage-derived foam cells during inflammation.
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Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 144, No. 11, pp. 556–559, November, 2007 相似文献
108.
目的:探讨过滤操作对一种免疫球蛋白G2(immunoglobin G2,IgG2)亚型表皮生长因子受体(epidermal growth factor receptor,EGFR)单克隆抗体(单抗)生物类似药(similar biotherapeutic product,SBP)候选药中不溶性微粒的影响。方法:利用微流数字成像(microflow digital imaging,MDI)技术对某厂家生产的IgG2亚型EGFR单抗SBP候选药与其原研药(reference biotherapeutic product,RBP)中不同粒径的不溶性微粒进行比较;采用0.22 μm的滤器对EGFR单抗SBP候选药进行过滤,并采用MDI法立即对不同粒径和性质的不溶性微粒进行检测和分析;再将过滤后的EGFR单抗SBP候选药在室温静置2 h,并采用MDI法对不同粒径和性质的不溶性微粒进行检测和分析。结果:某IgG2亚型EGFR单抗SBP候选药中不同粒径的不溶性微粒数量明显高于RBP;用0.22 μm的滤器过滤后,EGFR单抗SBP候选药中的不溶性微粒数由8.51×105粒·mL-1降为1.52×104粒·mL-1,且主要成分蛋白聚体、气泡和纤维均明显减少;室温静置2 h后,其中的不溶性微粒数由1.52×104粒·mL-1增加至3.23×104粒·mL-1,且增加的微粒主要为蛋白聚体。结论:与原研药相比,该EGFR单抗SBP候选药蛋白聚体水平较高,过滤后有明显改善,但随着放置时间延长,蛋白聚体含量又有明显增加。这提示我们需加强研发,以提高SBP候选药的产品质量、安全性和有效性。 相似文献
109.
Amélie Aïm-Eusébi Emmanuel Prothon Catherine Majerholc Diana Barger Yazdan Yazdanpanah Jean-Pierre Aubert 《The European journal of general practice》2018,24(1):60-67
Background: Many people in Europe remain undiagnosed for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV).Objectives: To evaluate acceptability and effectiveness of a questionnaire designed to facilitate identification of risk factors for these viruses.Methods: We performed an observational study, in a prospectively enrolled cohort of patients in Paris (France) seen in 2014. Eighteen GPs administered a questionnaire to the first 50 patients, collecting information about risk factors. GPs were randomized into two groups: A (self-administered questionnaire) and B (GP-administered questionnaire). We used the overall response rate to assess the acceptability of the questionnaire. We used the rate of newly identified risk factors and compared the number of tests performed one year before and immediately after the intervention to assess the effectiveness of the questionnaire.Results: 842 patients were randomized: 349 (41.5%) in group A and 493 (58.5%) in group B. Acceptability was 88.5% (95%CI: 86.3–90.6); 93.1% (95%CI: 90.5–95.8) in-group A and 85.2% (95%CI: 82.1–88.3) in group B (P?=?0.0004). Prevalence of risk factors was 51.8% (95%CI: 48.2–54.4) and 58.3% were newly identified (95%CI: 52.9–63.7). The number of HIV tests performed during the four weeks after intervention increased by 27% compared to the same period one year before (P?=?0.22). It increased by 113% (P?=?0.005) and 135% (P?=?0.005) for HBV and HCV, respectively.Conclusion: The questionnaire proved acceptable and effective in identifying risk factors for HIV, HBV and HCV in general practice. 相似文献
110.
Afnan Sh. Ahmed Muhammad Taher Deny Susanti Juliana Md. Jaffri 《Pharmaceutical development and technology》2018,23(8):751-760
The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze–thaw method. Response surface methodology with Box–Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze–thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12?hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze–thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation. 相似文献