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目的:观察低血糖指数的膳食对2型糖尿病患者氧化应激状态的影响。方法:2004-10/11在上海市静安区二个社区卫生服务中心招募受试者,经医生明确诊断为2型糖尿病、病程超过6个月,体质量指数≥24kg/m2的老年糖尿病志愿者43名,受试者对试验知情同意。采用随机交叉试验随机分配至低血糖指数饮食组和高血糖指数饮食组,每种膳食分别连续使用4周,间隔洗脱期4周,比较试验前后患者超氧化物歧化酶、脂质过氧化产物丙二醛和谷胱甘肽过氧化物酶含量的变化。结果:受试者依从性好,除1人因试验期间发现肿瘤而退出试验,42名志愿者按设计要求完成试验。膳食干预后低血糖指数饮食组和高血糖指数饮食组的超氧化物歧化酶活力分别升高了15.68%和21.33%,丙二醛水平分别下降23.94%和21.55%,谷胱甘肽过氧化物酶活力分别升高了15.74%和17.09%;干预后低血糖指数饮食组丙二醛下降水平与高血糖指数饮食组比较差异有显著性意义(P<0.05),而超氧化物歧化酶和谷胱甘肽过氧化物酶活性两组间差异无显著性意义(P>0.05)。结论:在控制总能量的基础上给予平衡膳食能够改善其氧化应激水平,采用低血糖指数食物有助于氧化应激水平的改善。 相似文献
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目的:分析力学刺激体外骨髓间充质干细胞所产生增殖分化等生物学效应的影响及其力化学信号转导途径。资料来源:因特网上检索PubMed数据库中2000-01/2006-06期间有关力学刺激对骨髓干细胞作用效应进展的英文文章,检索词“stem cel1,marrow mesenchymal stem cells,mechanical stimulation,stress”,同时检索CNKI中国知网医学文献数据库2000-01/2006-06期间的相关文章,检索词为“干细胞、骨髓间充质干细胞、机械刺激、应力”。资料选择:对资料进行筛选,选取相关文章查找全文。纳入标准:①骨髓间充质干细胞相关生物学特性。②体外细胞加载的应力分类及相应力学装置的特点。③应力对细胞影响的研究。④能获取文章的全文。排除标准:①较陈旧的文献。②重复研究。资料提炼:共收集关于86篇体外骨髓干细胞及力学干预的相关文献。其中30篇符合纳入标准。资料综合:①骨髓干细胞具有高度增殖及多向分化能力,可通过体外培养、干预作为细胞组织工程的理想种子细胞。②力学刺激是体外调节细胞生物学效应的重要途径,其中力学分类有:流体切应力、静止压应力、张应力、离心力以及单个细胞的吸吮力等,介绍各种力以及相应的力学装置的特点。③骨髓干细胞加载各种应力干预后产生的生物学效应,以及细胞应力学刺激的机制、信号转导途径。结论:力学刺激可影响骨髓间充质干细胞生物学特性,在适当的力学刺激条件下,促进细胞的增殖与分化,为骨组织工程提供新的技术手段,同时也为临床应用牵拉成骨的骨再生过程提供理论依据。 相似文献
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Modeling the combination of amphotericin B, micafungin, and nikkomycin Z against Aspergillus fumigatus in vitro using a novel response surface paradigm 下载免费PDF全文
Brun YF Dennis CG Greco WR Bernacki RJ Pera PJ Bushey JJ Youn RC White DB Segal BH 《Antimicrobial agents and chemotherapy》2007,51(5):1804-1812
Response surface methods for the study of multiple-agent interaction allow one to model all of the information present in full concentration-effect data sets and to visualize and quantify local regions of synergy, additivity, and antagonism. In randomized wells of 96-well plates, Aspergillus fumigatus was exposed to various combinations of amphotericin B, micafungin, and nikkomycin Z. The experimental design was comprised of 91 different fixed-ratio mixtures, all performed in quintuplicate. After 24 h of drug exposure, drug effect on fungal viability was assessed using the tetrazolium salt 2,3-bis {2-methoxy-4-nitro-5-[(sulfenylamino) carbonyl]-2H-tetrazolium-hydroxide} (XTT) assay. First, we modeled each fixed-ratio combination alone using the four-parameter Hill concentration-effect model. Then, we modeled each parameter, including the 50% inhibitory concentration (IC(50)) effect, versus the proportion of each agent using constrained polynomials. Finally, we modeled the three-agent response surface overall. The overall four-dimensional response surface was complex, but it can be explained in detail both analytically and graphically. The grand model that fit the best included complex polynomial equations for the slope parameter m and the combination index (equivalent to the IC(50) for a fixed-ratio concentration, but with concentrations normalized by the respective IC(50)s of the drugs alone). There was a large region of synergy, mostly at the nikkomycin Z/micafungin edge of the ternary plots for equal normalized proportions of each drug and extending into the center of the plots. Applying this response surface method to a huge data set for a three-antifungal-agent combination is novel. This new paradigm has the potential to significantly advance the field of combination antifungal pharmacology. 相似文献
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Fibroblast growth factor 2 decreases bleomycin‐induced pulmonary fibrosis and inhibits fibroblast collagen production and myofibroblast differentiation 下载免费PDF全文
Hyun Young Koo Lamis MF El‐Baz StaceyL House Sarah N Cilvik Samuel J Dorry Nahla M Shoukry Mohamed L Salem Hani S Hafez Nickolai O Dulin David M Ornitz Robert D Guzy 《The Journal of pathology》2018,246(1):54-66
Fibroblast growth factor (FGF) signaling has been implicated in the pathogenesis of pulmonary fibrosis. Mice lacking FGF2 have increased mortality and impaired epithelial recovery after bleomycin exposure, supporting a protective or reparative function following lung injury. To determine whether FGF2 overexpression reduces bleomycin‐induced injury, we developed an inducible genetic system to express FGF2 in type II pneumocytes. Double‐transgenic (DTG) mice with doxycycline‐inducible overexpression of human FGF2 (SPC‐rtTA;TRE‐hFGF2) or single‐transgenic controls were administered intratracheal bleomycin and fed doxycycline chow, starting at either day 0 or day 7. In addition, wild‐type mice received intratracheal or intravenous recombinant FGF2, starting at the time of bleomycin treatment. Compared to controls, doxycycline‐induced DTG mice had decreased pulmonary fibrosis 21 days after bleomycin, as assessed by gene expression and histology. This beneficial effect was seen when FGF2 overexpression was induced at day 0 or day 7 after bleomycin. FGF2 overexpression did not alter epithelial gene expression, bronchoalveolar lavage cellularity or total protein. In vitro studies using primary mouse and human lung fibroblasts showed that FGF2 strongly inhibited baseline and TGFβ1‐induced expression of alpha smooth muscle actin (αSMA), collagen, and connective tissue growth factor. While FGF2 did not suppress phosphorylation of Smad2 or Smad‐dependent gene expression, FGF2 inhibited TGFβ1‐induced stress fiber formation and serum response factor‐dependent gene expression. FGF2 inhibition of stress fiber formation and αSMA requires FGF receptor 1 (FGFR1) and downstream MEK/ERK, but not AKT signaling. In summary, overexpression of FGF2 protects against bleomycin‐induced pulmonary fibrosis in vivo and reverses TGFβ1‐induced collagen and αSMA expression and stress fiber formation in lung fibroblasts in vitro, without affecting either inflammation or epithelial gene expression. Our results suggest that in the lung, FGF2 is antifibrotic in part through decreased collagen expression and fibroblast to myofibroblast differentiation. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
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Bundó M Muñoz L Pérez C Montero JJ Montellà N Torán P Pera G 《Annals of vascular surgery》2010,24(8):985-993
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NANOS3 function in human germ cell development 总被引:1,自引:0,他引:1
Human infertility is common and frequently linked to poor germ cell development. Yet, human germ cell development is poorly understood, at least in part due to the inaccessibility of germ cells to study especially during fetal development. Here, we explored the function of a highly conserved family of genes, the NANOS genes, in the differentiation of human germ cells from human embryonic stem cells. We observed that NANOS-1, -2 and -3 mRNAs and proteins were expressed in human gonads. We also noted that NANOS3 was expressed in germ cells throughout spermatogenesis and oogenesis and thus, focused further efforts on this family member. NANOS3 expression was highest in human germ cell nuclei where the protein co-localized with chromosomal DNA during mitosis/meiosis. Reduced expression of NANOS3 (via morpholinos or short hairpin RNA) resulted in a reduction in germ cell numbers and decreased expression of germ cell-intrinsic genes required for the maintenance of pluripotency and meiotic initiation and progression. These data provide the first direct experimental evidence that NANOS3 functions in human germ cell development; indeed, NANOS3 is now one of just two genes that has been directly shown to function in germ cell development across diverse species from flies, worms, frogs and mice to humans [the other is BOULE, a member of the Deleted in Azoospermia (DAZ) gene family]. Findings may contribute to our understanding of the basic biology of human germ cell development and may provide clinical insights regarding infertility. 相似文献
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