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41.
AIM: To investigate the effects of xeroderma pigmentosum group D (XPD) gene on the proliferation of human umbilical arterial smooth muscle cells (HUASMCs) induced by oxidized low-density lipoprotein (Ox-LDL). METHODS: The recombinant plasmid pEGFP-N2/XPD was transfected into HUASMCs by liposome. The cells were divided into blank control group, pEGFP-N2 group, pEGFP-N2/XPD group, Ox-LDL group, Ox-LDL+pEGFP-N2 group and Ox-LDL+pEGFP-N2/XPD group. The proliferation rate of the cells was detected by MTT and EdU assays. The apoptotic rate and cell cycle distribution were analyzed by flow cytometry. The protein levels of XPD, caspase-3, Bcl-2 and Bax were determined by Western blot. RESULTS: Compared with blank control group, the expression of XPD was increased in pEGFP-N2/XPD group (P<0.05). According to the results of MTT and EdU assays, the cell proliferation in pEGFP-N2/XPD group was reduced compared with blank control group (P<0.05). Compared with Ox-LDL group, the cell proliferation in Ox-LDL+pEGFP-N2/XPD group was significantly inhibited (P<0.05). According to the results of flow cytometry, the cell proportion of S phase decreased and the G0/G1-phase cell proportion increased significantly in pEGFP-N2/XPD group and Ox-LDL+pEGFP-N2/XPD group compared with blank control group and Ox-LDL group, repectively (P<0.05). Compared with blank control group and Ox-LDL group, the protein level of Bcl-2 decreased and the protein levels of Bax and cleaved caspase-3 increased in pEGFP-N2/XPD group and Ox-LDL+pEGFP-N2/XPD group, respectively (P<0.05). CONCLUSION: XPD inhibits the proliferation of HUASMCs and promotes their apoptosis, and reduces the promoting effect of Ox-LDL on the proliferation of HUVSMCs. XPD may be the target for treatment of atherosclerosis.  相似文献   
42.
[目的] 研究去势术对雄性中华田园犬脂代谢的影响。[方法] 将12只年龄、体重相近的中华田园犬分为非手术组和去势组,对去势组中华田园犬进行去势手术,观察并测定术前第1天、术后第14天、术后第21天血清中甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白(LDL)、高密度脂蛋白(HDL)含量,以非手术组作为对照,分析去势术对雄性犬脂代谢的影响。[结果] 去势组与非手术组相比,血清中TG含量在第14天到第21天显著上升;血清中TC含量相比非手术组呈下降趋势;HDL第14天和第21天都低于非手术组;LDL都高于非手术组,整体呈上升趋势。[结论] 去势手术会影响雄性中华田园犬机体脂类代谢,会导致去势犬甘油三酯升高,总胆固醇和高密度脂蛋白下降,低密度脂蛋白上升。  相似文献   
43.
简述了补体、抗体、C-反应蛋白、血清淀粉样蛋白、甘露糖凝集素、表面活性蛋白、纤粘蛋白等七类调理素的研究,报道了新发现的调理素低密度脂蛋白和高密度脂蛋白,并对抗感染免疫学研究的新视角进行了展望。  相似文献   
44.
This study was conducted to evaluate the effect of dietary fenugreek seed extract (FSE) on growth performance, apparent total tract digestibility (ATTD), diarrhoea scores, blood profiles, faecal microflora and faecal gas emission in weanling pigs. A total of 135 weanling pigs [(Yorkshire × Landrace)  × Duroc] with an average BW of (7.96 ± 1.03 kg; 28 days of age) were used in a 42‐day study. Piglets were randomly allotted to three experimental diets with nine replicate pens and five pigs per pen. Dietary treatments were as follows: CON, basal diet; FSE1, basal diet + 0.1% FSE; FSE2, basal diet + 0.2% FSE. Pigs were fed with phase 1 (0–14 days) and phase 2 (14–42 days) diets in the form of mash. Average daily gain (ADG) was linearly increased (p = 0.031) by FSE supplementation compared with CON diet during days 0–14. From days 14–42, FSE2 diet had increased ADG and growth efficiency (G/F) compared with the CON diet (p = 0.014 and 0.026 respectively). Moreover, ADG and G/F were increased by FSE supplementation during days 0–42 (linear, p = 0.037 and 0.014 respectively). Energy digestibility was higher (linear, p = 0.030) by FSE supplementation at 6 weeks. On day 42, dietary supplementation of FSE linearly increased red blood cells (RBC) and immunoglobulin G (IgG) concentration (p = 0.042 and 0.038 respectively). Piglets fed FSE2 diet had higher (linear, p = 0.025) serum high‐density lipoprotein cholesterol (HDL‐C) concentration compared with those fed CON diet. However, piglets fed FSE2 diet had linearly reduced faecal ammonia (NH3) and hydrogen sulphide (H2S) gas emission compared with those fed the CON diet (p = 0.018 and 0.010 respectively). In conclusion, FSE supplementation increased the performance and reduced faecal gas emission in weanling pigs.  相似文献   
45.
46.
对零世代8周龄肉鸡血浆极低密度脂蛋白(VLDL)浓度进行降低腹脂的间接选择,明显改善了一世代低VLDL系鸡生长期饲料转化率,并对8周龄血浆甘油三酯、总脂浓度产生明显影响,但对8周龄血浆胆固醇浓度及各周龄体重未产生明显影响。低VLDL系鸡饲料转化率优于高VLDL系,肉仔鸡耗料比,5~9周龄高VLDL系明显高于低VLDL系(P=0.05),而7~9周龄高VLDL系显著高于低VLDL系(P<0.01)。8周龄血浆甘油三酯及总脂浓度,高VLDL系显著高于低VLDL系(P<0.001,P<0.01)。一世代高、低VLDL系血浆VLDL和腹脂的变异系数仍然很大,继续选择以培育脂肪更低、饲料转化率更高的低脂系是可能的,各周龄体重的变异系数不高(小于25%),但高、低VLDL系的变异系数大大高于总变异系数,表明选择使高、低VLDL系体重的整齐度降低,因此,继续对血浆VLDL浓度结合体重选择效果会更好。  相似文献   
47.
应用二维凝胶电泳(2-DE)技术分离家蚕孤雌生殖蚁蚕总蛋白,并和正常蚁蚕总蛋白进行比较,得到46个可能与家蚕孤雌生殖相关的差异蛋白点。对这些差异蛋白点进行胶内酶解后基质辅助激光解吸电离串联飞行时间质谱(MALDI-TOF-TOFMS)分析,经数据库搜索鉴定,确定其中一个差异蛋白点为脂蛋白30K lipoprotein precursor(30K LPP)。通过5′-RACE技术克隆到30KLPP脂蛋白的全长cDNA序列。生物信息学分析显示该差异蛋白基因全长917bp,编码261个氨基酸,理论分子质量为30.013kD,等电点为7.193;结构域和三级结构预测显示该蛋白包含1个Lipoprotein-11结构域和12个β-折叠。预测其信号肽概率为1.000,定位在1~20aa区域,即可能存在信号肽。细胞定位预测显示该蛋白可能分泌到胞外(SP值为0.934)。分析结果有助于进一步研究30KLPP脂蛋白结构与功能的关系。  相似文献   
48.
根据已发表的丝状支原体丝状亚种SC型(MmmSC)LppQ基因序列设计引物,从MmmSC HVRIx株中扩增出了LppQN末端基因,并将其分别克隆到pUC18和pUC19上,利用一步重叠延伸PCR突变方法将其66位的TGA突变为TGG,经克隆与序列测定证实突变成功后,将已突变的LppQN末端基因插入原核表达载体pET32a的多克隆位点,成功地构建了LppQN末端基因原核表达载体pET32a-LppQ,为其下一步体外表达奠定了基础。  相似文献   
49.
Two flavonoids, gnaphaliin and tiliroside, isolated from Helichrysum italicum, were studied in vitro for their capacity to inhibit Cu(2+)-induced human low density lipoprotein (LDL) and diluted plasma oxidation. LDL oxidation was monitored by conjugated diene, thiobarbituric acid-reactive substances (TBARS) formation and electrophoretic mobility on agarose gel. Gnaphaliin and tiliroside increased the lag-phase for diene conjugate production in a dose-dependent manner. The reduction of TBARS production confirmed the antioxidant activity of gnaphaliin and tiliroside with 50% inhibitory concentration (IC(50)) values of 8.0+/-3.9 microM and 7.0+/-2.6 microM respectively. Furthermore, the flavonoids negated the Cu(2+)-induced increase in electrophoretic mobility of LDL. Antioxidant activity of gnaphaliin and tiliroside was significantly different when diluted plasma was oxidised by adding 1 mM CuSO(4). Although both flavonoids again reduced the TBARS production, tiliroside showed higher activity than gnaphaliin (IC(50)=10.6+/-2.5 microM vs. IC(50)>50 microM). In conclusion, tiliroside and gnaphaliin are antioxidants against in vitro Cu(2+)-induced LDL oxidation in the same order of magnitude compared to that of the reference drug, probucol.  相似文献   
50.
王海利  刘妍 《安徽农业科学》2010,(25):13588-13589
论述了动物体内极低密度脂蛋白受体的结构、功能,对极低密度脂蛋白受体与载脂蛋白受体的进化关系进行了研究,并对其功能进行了推测。  相似文献   
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