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61.
目的:检测鼻咽癌患者外周血中Treg细胞与Th17细胞的比例以及相关细胞因子如IL-6、TGF-β1的变化.方法:选取我院鼻咽癌患者50例,另选取健康志愿者50例,鼻咽炎患者50例作为对照.采用流式细胞术检测外周血中Th17细胞和Treg细胞百分率,ELISA法检测血清中细胞因子TGF-β1、IL-6的水平,分析其相关性.结果:鼻咽癌外周血中Treg和Th17细胞占CD4+T细胞的比例均升高,与鼻咽炎组、正常对照组比较,均有显著性差异(P<0.05);且Treg细胞与Th17细胞呈正相关(P<0.05);鼻咽癌外周血中TGF-β1、IL-6的水平均明显高于鼻咽炎组、正常对照组,均有显著性差异(P<0.05);鼻咽癌患者外周血Th17细胞、Treg细胞分别与血清中IL-6、TGF-β1水平呈正相关(P<0.05).结论:鼻咽癌患者外周血中Treg、Th17细胞比例升高,且两者呈正相关;鼻咽癌患者患者血清中TGF-β1、IL-6水平升高,可能影响Treg与Th17细胞的平衡. 相似文献
62.
Objective
To examine nicotine (N) and cotinine (C) effects on trophoblast cells (TCs) and human umbilical vein endothelial cells (HUVEC) secretion of soluble fms-like tyrosine kinase (sFlt-1), soluble endoglin (sENG), placental growth factor (PlGF), transforming growth factor-beta (TGF-beta) and vascular endothelial growth factor (VEGF).Study design
Human placentas and umbilical cords were collected from uncomplicated pregnancies at term from a total of 24 non-smoking women with a history of normal blood pressure. TCs and HUVEC were cultured for 24 h with C or N (from 10−12 to 10−7 M).Main outcome measures
sFlt-1, sENG, PlGF, TGF-beta and VEGF release and messenger RNA (mRNA) expression were evaluated by ELISA and real-time polymerase chain reaction (PCR), respectively.Results
N and C reduced sFlt-1, sENG and PlGF release by TCs and TGF-beta release by HUVEC. Conversely, N and C increased PlGF secretion, while N alone increased sFlt-1 release by HUVEC. N and C were able to modulate VEGF mRNA expression in HUVEC.Conclusions
Our results suggest that N and C affect the balance of some important vasoactive factors released by TCs and HUVEC. This might be one of the possible mechanism through which smoke reduces the risk of hypertensive disorders during pregnancy as well as contributes to the well known detrimental effects of smoking on fetal development. 相似文献63.
目的 探讨生长因子β1在儿童哮喘中的作用及观察孟鲁司特钠对其的影响。方法 筛选2009年9月-2010年9月我院哮喘专病门诊轻度持续哮喘患儿60例及来院健康体检儿童30例,将哮喘患儿随机分成孟鲁司特钠组和安慰剂对照组;采用双抗夹心酶联免疫吸附试验( ELISA)、RT-PCR技术分别检测治疗前后患儿血浆中TGF-β1水平和外周血单个核细胞(PBMC)中TGF-β1mRNA表达;采用流式细胞技术,检测表达叉状头/翅膀状螺旋转录因子3的CD4T调节细胞(Foxp3+ CD4+ Treg)及各亚型的比例。结果 (1)血浆中TGF-β1水平:治疗前哮喘组[(11.51±1.12) ng/L]明显低于健康对照组[(47.92±1.52) ng/L](q=20.01,P<0.01);治疗后,孟鲁司特钠组[ (20.03±1.14)ng/L]高于安慰剂组[(12.10±3.91) ng/L](q=14.62,P<0.05),但均值仍低于健康对照组;(2)外周血单个核细胞中TGF-β1 mRNA表达:治疗前哮喘组(0.31 +0.07)明显低于健康对照组(0.61±0.2) (q =8.97,P<0.05);治疗后,孟鲁司特钠组(0.46±0.13)表达高于安慰剂组(0.32±0.04)(q=8.25,P<0.05),但仍低于健康对照组;(3)流式细胞检测结果各组间比较差异有统计学意义(P<0.05):哮喘患儿与健康对照组相比,Foxp3+ CD4+ Treg细胞比例增加[(8.30±1.30)%,(6.05±1.80)%];其中CD45 RA+ Foxp3lo比例增高[(4.60±1.04)%,(3.27±1.03)%];CD45 RA - Foxp3h1比例降低[(0.75±0.13)%,(0.93±0.26)%];CD45 RA-Foxp3lo比例两组差异无统计学意义。治疗后,孟鲁司特钠组较安慰剂组,aTreg细胞占Foxp3+ CD4+ Treg比例增加[(1.16±0.24)%,(0.89±0.22)%],差异有统计学意义。结论哮喘儿童体内存在血浆及外周血单个核细胞中TGF-β1表达的降低,可能是导致哮喘发病的重要原因;孟鲁司特钠能有效改善TGF-β1的表达并通过调节Foxp3的表达来发挥治疗作用。 相似文献
64.
目的评价局部晚期非小细胞肺癌(LA-NSCLC)同步放化疗患者放疗前、放疗中和放疗后血清转化生长因子-β1(TGF-β1)、白细胞介素-6(IL-6)的变化及调强放射治疗计划剂量体积直方图(DVH)参数与放射性肺炎的相关性。方法 49例行同步放化疗的LA-NSCLC患者,在治疗前、治疗过程中每周及治疗后第13周采用ELISA法检测血清TGF-β1和IL-6水平。应用Varian Eclipse DX计划系统,设计并评估调强放射治疗计划,并采集相关物理学参数。放射性肺炎按RTOG急性放射性肺炎标准评价,评价终点为≥2级放射性肺炎。结果 11例发生了放射性肺炎。放射性肺炎组放疗前血清TGF-β1浓度与无放射性肺炎组比较差异无统计学意义,有放射性肺炎组在放疗中各个时间点和放疗后均高于无放射性肺炎组(P<0.05);血清IL-6浓度在放疗前、放疗中各个时间点和放疗后有放射性肺炎组均高于无放射性肺炎组(P<0.05);放射性肺炎组DVH相关参数(包括肿瘤靶区的平均剂量、最大剂量、最小剂量,肺脏V5、V10、V20、平均剂量、正常组织并发症概率,食管V45,心脏平均受照剂量及脊髓最大受照剂量)与放射性肺炎组比较差异无统计学意义。结论 LA-NSCLC患者同步放化疗时,在使用DVH相关参数严格限制正常组织受照剂量的同时,血清TGF-β1和IL-6可以作为放射性肺炎的预测因子。 相似文献
65.
Herein we describe a bio-inspired, affinity binding alginate-sulfate scaffold, designed for the presentation and sustained release of transforming growth factor beta 1 (TGF-β1), and examine its effects on the chondrogenesis of human mesenchymal stem cells (hMSCs). When attached to matrix via affinity interactions with alginate sulfate, TGF-β1 loading was significantly greater and its initial release from the scaffold was attenuated compared to its burst release (>90%) from scaffolds lacking alginate-sulfate. The sustained TGF-β1 release was further supported by the prolonged activation (14 d) of Smad-dependent (Smad2) and Smad-independent (ERK1/2) signaling pathways in the seeded hMSCs. Such presentation of TGF-β1 led to hMSC chondrogenic differentiation; differentiated chondrocytes with deposited collagen type II were seen within three weeks of in vitro hMSC seeding. By contrast, in scaffolds lacking alginate-sulfate, the effect of TGF-β1 was short-term and hMSCs could not reach a similar differentiation degree. When hMSC constructs were subcutaneously implanted in nude mice, chondrocytes with deposited type II collagen and aggrecan typical of the articular cartilage were found in the TGF-β1 affinity-bound constructs. Our results highlight the fundamental importance of appropriate factor presentation to its biological activity, namely - inducing efficient stem cell differentiation. 相似文献
66.
Corrigan F Vink R Blumbergs PC Masters CL Cappai R van den Heuvel C 《Neuroscience letters》2012,506(1):50-54
Neural stem cells (NSCs) are tissue-specific, multipotent stem cells that can differentiate into three cell lineages in the central nervous system: neurons, astrocytes and oligodendrocytes. The therapeutic potential of NSCs has fueled attempts to characterize the expression of genes that regulate their fate. In this study, NSCs from embryonic day 15 (E15) mouse embryos were differentiated for 1 (DF-1) or 2 (DF-2) days, and the gene expression patterns in the NSCs and in the DF-1 and DF-2 cells were measured by microarray and real-time RT-PCR. Among the analyzed genes, 1898 genes were up-regulated in the DF-1 and DF-2 cells relative to the NSCs, whereas 1642 genes were down-regulated. The up-regulated genes included Gfap, Smad6, Fst, Tgfb2 and Cdkn2. The down-regulated genes included Ccnb1, Ccnd1 and Ccnd2. We identified gene networks that were associated with BMP and TGF-beta2 signaling pathways using Ingenuity Pathway Analysis. Our results suggest that the differentiation of E15 NSCs into astrocytes is based on a combinatorial network of various signaling pathways, including cell cycle, BMP and TGF-beta2 signaling. 相似文献
67.
Cryptotanshinone inhibits LPS-induced proinflammatory mediators via TLR4 and TAK1 signaling pathway 总被引:1,自引:0,他引:1
Li X Lian LH Bai T Wu YL Wan Y Xie WX Jin X Nan JX 《International immunopharmacology》2011,11(11):1871-1876
Cryptotanshinone (CTN), one of the major constituents of tanshinones, was investigated for anti-inflammatory activity in the murine macrophage cell line RAW 264.7. CTN inhibited the production of nitric oxide (NO) production, as well as expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated macrophages. Since CTN was considered as inhibiting LPS-triggered phosphorylation of mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-κB activation, we consequently evaluated the expression of toll-like receptor 4 (TLR4) and CD14, as well as phosphorylation of TGF-β-activated kinase 1 (TAK1). CTN reduced the expression of CD14 and TLR4, and suppressed LPS-induced phosphorylation of TAK1. Furthermore, CTN significantly increased the survival rate against LPS challenge in D-galactosamine-sensitized mice, which was in line with in vitro results. These results suggested that CD14/TLR4 and TAK1 might be the potential molecular targets for addressing the protective effects of CTN on LPS-induced inflammatory effects in macrophages. 相似文献
68.
69.
Lack of Association between Serum Transforming Growth Factor-beta 1 and Cancer Mortality Risk in a Nested Case-control Study in Japan
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《Asian Pacific journal of cancer prevention》2009,10(2):273-278
We examined the potential role of serum TGF-beta 1 levels to predict cancer mortality risk in a nested casecontrolstudy within a large prospective cohort of middle-aged and elderly Japanese subjects. The cases were893 persons who provided blood samples at baseline and subsequently died of cancer from all sites during thefollow-up period. A total of 2,824 subjects were selected from the main study as controls, matched with the casesfor sex, age and study area. Serum TGF-beta 1 levels were measured using a quantitative sandwich enzymeimmunoassay. The odds ratios and 95% confidence intervals for each quartile were calculated using a conditionallogistic regression model. Mean serum TGF-beta 1 levels were approximately 36 ng/ml in both cases and controls,with no significant difference . Overall, serum TGF- beta 1 levels were not associated with total cancer mortalityafter adjustment for potential confounding factors like age, body mass index or cigarette smoking. Serum TGFbeta1 levels may thus not be associated with cancer mortality risk in apparently health individuals. 相似文献
70.
《Placenta》2014
The cellular expression, structure and function of endoglin, and its implication in several vascular disorders remain enigmatic, even 30 years after its discovery. Endoglin (CD105) is a homodimeric glycoprotein (180 kDa) constitutively expressed in the vascular endothelium. It is essential for cardiovascular development and mutations in the ENG gene lead to Hereditary Hemorrhagic Telangiectasia, a disorder characterized by arteriovenous malformations. Endoglin is also expressed in the syncytiotrophoblast throughout pregnancy, but transiently upregulated in the extravillous trophoblast of anchoring villi. Endoglin modulates responses to several TGF-β superfamily ligands and is essential for the negative regulation by TGF-β isoforms 1 and 3 of extravillous trophoblast differentiation. Membrane endoglin binds endothelial NO synthase and regulates its activation and vasomotor tone. There is also a circulating soluble form of endoglin (sEng; 65 kDa); its levels in the serum of women with preeclampsia are increased and correlated with disease severity. The exact sequence of sEng is still unresolved and the proposed mechanism of release from the syncytium by metalloproteases would not yield the expected size protein. The nature of the ligand sequestered by sEng is also an enigma. sEng is said to block the effects of TGF-β on NO-mediated vasorelaxation. However, sEng alone cannot scavenge these ligands for which it has very low affinity. sEng binds with high affinity to BMP9, which stimulates secretion from endothelial cells of the vascoconstrictor endothelin-1, also implicated in endothelial cell stabilization. It remains to be determined if scavenging of circulating BMP9 by sEng is important in preeclampsia and regulation of hypertension. 相似文献