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861.
862.
Ziru Li Ling Gao Hong Tang Yue Yin Xinxin Xiang Yin Li Jing Zhao Michael Mulholland Weizhen Zhang 《PloS one》2013,8(8)
Aims/hypothesis
The actions of peripherally administered nesfatin-1 on glucose homeostasis remain controversial. The aim of this study was to characterize the mechanisms by which peripheral nesfatin-1 regulates glucose metabolism.Methods
The effects of nesfatin-1 on glucose metabolism were examined in mice by continuous infusion of the peptide via osmotic pumps. Changes in AKT phosphorylation and Glut4 were investigated by Western blotting and immnuofluorescent staining. Primary myocytes, adipocytes and hepatocytes were isolated from male mice.Results
Continuous peripheral infusion of nesfatin-1 altered glucose tolerance and insulin sensitivity in mice fed either normal or high fat diet, while central administration of nesfatin-1 demonstrated no effect. Nesfatin-1 increases insulin secretion in vivo, and in vitro in cultured min6 cells. In addition, nesfatin-1 up-regulates the phosphorylation of AKT in pancreas and min6 islet cells. In mice fed normal diet, peripheral nesfatin-1 significantly increased insulin-stimulated phosphorylation of AKT in skeletal muscle, adipose tissue and liver; similar effects were observed in skeletal muscle and adipose tissue in mice fed high fat diet. At basal conditions and after insulin stimulation, peripheral nesfatin-1 markedly increased GLUT4 membrane translocation in skeletal muscle and adipose tissue in mice fed either diet. In vitro studies showed that nesfatin-1 increased both basal and insulin-stimulated levels of AKT phosphorylation in cells derived from skeletal muscle, adipose tissue and liver.Conclusions
Our studies demonstrate that nesfatin-1 alters glucose metabolism by mechanisms which increase insulin secretion and insulin sensitivity via altering AKT phosphorylation and GLUT 4 membrane translocation in the skeletal muscle, adipose tissue and liver. 相似文献863.
用已经构建的工程菌高效表达抗人胃癌链缺本并使用SephadexG-100柱层析分离纯化抗体蛋白。同时用免疫竞争抑制实验,测出单链抗体具有特异性结合胃癌抗原活性。 相似文献
864.
865.
中药"神曲"对脾虚小鼠肠道菌群的调整及肠保护作用研究 总被引:3,自引:1,他引:3
目的研究中药"神曲"对脾虚小鼠肠道菌群的调整及肠保护作用.方法1.昆明小白鼠,分成4组:A组(正常对照组),B组(脾虚自然恢复组),C组(神曲治疗组),D组(丽珠肠乐治疗组).2.检测结肠内容物和粪便标本的肠杆菌、肠球菌、双歧杆菌、类杆菌和乳酸杆菌数量.3.结肠组织光镜和电镜观察.结果脾虚小鼠给予神曲水煎剂治疗后,肠杆菌、肠球菌、双歧杆菌、类杆菌和乳酸杆菌数量逐渐恢复正常,肠壁肌层厚度增加,杯状细胞数量增多,肠黏膜微绒毛排列紊乱、线粒体肿胀显著改善,明显好于自然恢复组,与丽珠肠乐治疗组相比差异无显著性.结论中药神曲对脾虚小鼠具有肠道菌群调整及促进损伤肠组织恢复的作用. 相似文献
866.
Gong M Wang JD Zhang J Yang H Lu XF Pei Y Cheng JQ 《Acta biochimica et biophysica Sinica》2006,38(4):233-240
A Bacillus strain,denoted as PY-1,was isolated from the vascular bundle of cotton.Biochemical,physiological and 16S rDNA sequence analysis proved that it should belong to Bacillus subtilis.The PY-1strain showed strong ability against many common plant fungal pathogens in vitro.The antibiotics producedby this strain were stable in neutral and basic conditions,and not sensitive to high temperature.From theculture broth of PY-1 strain,five antifungal compounds were isolated by acidic precipitation,methanolextraction,gel filtration and reverse-phase HPLC.Advanced identification was performed by mass spec-trometry and nuclear magnetic resonance spectroscopy.These five antifungal compounds were proved to bethe isomers of iturin A:A2,A3,A4,A6 and A7.In fast atom bombardment mass spectrometry/mass spec-trometry collision-induced dissociation spectra,fragmentation ions from two prior linear acylium ions wereobserved,and the prior ion,Tyr-Asn-Gln-Pro-Asn-Ser-βAA-Asn-CO~ ,was first reported. 相似文献
867.
利用简并PCR技术从野生花生种(Arachis ipaensis Krapov. et W. C. Greg.)的基因组中扩增分离Ty1-copia类(1类)和Ty3-gypsy类(2类)反转录转座子RT基因,并对其序列特征、多样性、系统进化关系及转录活性进行分析。结果显示:对于1和2类RT基因,目的条带分别约为260和430 bp;分离获得了23和32条序列,长度范围分别为262~266、395~435 bp;AT所占比例分别为61.60%~69.17%和55.79%~61.34%;核苷酸序列间相似性分别为52.5%~98.9%和45.0%~98.8%,氨基酸序列间相似性分别为39.8%~100%和9.0%~97.2%。其中2类基因的异质性高于1类;1类和2类基因分别有3条和15条发生了无义突变,2类的无义突变发生率远高于1类。1类基因的保守基序保守性较高,2类的保守基序呈一定程度的变异。代表序列的蛋白质三级结构基本类似。聚类分析结果显示,1类和2类基因可被分为5个和6个家族。1类和2类基因都有部分序列与其他物种的RT基因序列亲缘关系较近,表明它们之间可能存在两类反转录转座子的横向传... 相似文献
868.
本文报道了中国苋科苋属的一新记录归化植物——广布苋(Amaranthus graecizans L.)。该种植株常匍匐,叶片狭长椭圆形至线状披针形,有时线形或菱形卵形,长至少为宽的2.5倍,花被片3枚,近等长,与中国有分布的本属其他物种有所区别。该种原产于欧洲地中海地区、非洲北部至亚洲西部,归化于欧洲其他地区、东亚、澳大利亚、北美洲以及我国的河南、河北和山东等地区。该种易与苋属其他种类相混淆,因此其在我国的分布区可能被低估。此外,本文还对该种的种下等级以及该种的相似种进行了区分,并对该种下亚种Amaranthus graecizans subsp. thellungianus (Nevski) Gusev与国内文献记载的腋花苋(Amaranthus roxburghianus Kung)之间的关系作了说明与澄清。 相似文献
869.
Jing Liu Liting Zhang Yijia Tian Shuting Wan Min Hu Shasha Song Meihua Zhang Qian Zhou Yu Xia Xietong Wang 《Journal of cellular and molecular medicine》2022,26(15):4357
Obstetric antiphospholipid syndrome (OAPS) is mediated by antiphospholipid antibodies (aPLs, and anti‐β2 glycoprotein I antibody is the main pathogenic antibody), and recurrent abortion, preeclampsia, foetal growth restriction and other placental diseases are the main clinical characteristics of placental pathological pregnancy. It is a disease that seriously threatens the health of pregnant women. Hydroxychloroquine (HCQ) was originally used as an anti‐malaria drug and has now shown benefit in refractory OAPS where conventional treatment has failed, with the expectation of providing protective clinical benefits for both the mother and foetus. However, its efficacy and mechanism of action are still unclear. After clinical data were collected to determine the therapeutic effect, human trophoblast cells in early pregnancy were prepared and treated with aPL. After the addition of HCQ, the proliferation, invasion, migration and tubule formation of the trophoblast cells were observed so that the therapeutic mechanism of HCQ on trophoblast cells could be determined. By establishing an obstetric APS mouse model similar to the clinical situation, we were able to detect the therapeutic effect of HCQ on pathological pregnancy. The normal function of trophoblast cells is affected by aPL. Antibodies reduce the ability of trophoblast cells to invade and migrate and can impair tubule formation, which are closely related to placental insufficiency. HCQ can partially reverse these side effects. In the OAPS mouse model, we found that HCQ prevented foetal death and reduced the incidence of pathological pregnancy. Therefore, HCQ can improve pregnancy outcomes and reverse the aPL inhibition of trophoblast disease. In OAPS, the use of HCQ needs to be seriously considered. 相似文献
870.