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441.
AIM: To investigate the pro-apoptotic effect of T0901317, an artificial agonist of liver X receptor α (LXRα), on human breast cancer MDA-MB-231 cells and its mechanism. METHODS: MDA-MB-231 cells were treated with different concentrations (0, 10, 20 and 40 μmol/L) of T0901317 for different time (0, 12, 24 and 48 h). The cell apoptosis was determined by Annexin V/propidium iodide staining and Hoechst 33342 staining. The expression of apoptosis-related proteins, such as Bcl-2, caspase 3 and cleaved caspase-3, and LXRα was determined by Western blot. The mRNA expression of Bcl-2 and LXRα was analyzed by RT-qPCR. RESULTS: T0901317 induced the cell apoptosis in a dose-and time- dependent manner. The expression of cleaved caspase-3 and LXRα was up-regulated, but Bcl-2 was down-regulated by T0901317. The mRNA expression of Bcl-2 was down-regulated, while LXRα was up-regulated by T0901317.CONCLUSION: T0901317 up-regulates LXRα expression and induces the apoptosis of MDA-MB-231 cells.  相似文献   
442.
鹅短期强制填饲形成肥肝后,终止填饲观察肝脏生理性恢复情况。终填15 d、30 d后,体重和肝脏重快速恢复,接近正常;血液中TBA、TG等变化规律不明显,CHO终填30 d恢复,TP、ALB、GLO等体症蛋白含量变化不显著,ALT、AST、LDH、CHE等酶类填饲后大幅上升,终填后迅速回复,其中AST填后含量达191.8 U.L-1,升高2.87倍,终填15 d、30 d回复到正常的106.67%和84.44%;肝细胞内脂肪空泡迅速减少,终填30 d基本消失,向正常肝细胞过渡。试验结果表明肥肝生产是正常可逆的生理过程,通过自然放养,可基本回复到正常状态。  相似文献   
443.
AIM:To discover the expression profile of microRNAs (miRNAs) in mouse fibrotic liver tissues induced by carbon tetrachloride (CCl4), and to investigate the functions of these differential miRNAs based on the gene ontology (GO) analysis and KEGG Pathway analysis. METHODS:The mice were randomly divided into normal group and model group. Liver fibrosis was induced by subcutaneous injection of CCl4. miRNA expression profile of the liver tissues was assayed by a mouse miRNA microarray (Agilent 12.0). The differential expression of miRNAs between the normal and model mice was screened, and GO analysis and KEGG Pathway analysis were performed to determine the functions of these differential miRNAs. RESULTS:Thirty-nine miRNAs with differential expression were discovered in the model mice compared with the normal mice, among which 23 were up-regulated and 16 were down-regulated. GO analysis and KEGG Pathway analysis indicated that most pathological processes of liver fibrosis regulated by miRNAs included cell proliferation and activation, cell apoptosis, cell cycle, cell adhesion, inflammatory reaction, cell migration, transforming growth factor β (TGF-β) signaling pathway, Wnt signaling pathway and proteometabolism process. GO analysis revealed that the key up-regulated miRNAs were mmu-miR-322, mmu-miR-15b, mmu-miR-195, mmu-miR-200b and mmu-miR-214, and the key down-regulated miRNAs were mmu-miR-16, mmu-miR-130a, mmu-miR-101b, mmu-miR-30a and mmu-miR-30e. Analyzing the target genes screened out by GO analysis and Pathway analysis simultaneously, we found that the key up-regulated miRNAs included mmu-miR-200b, mmu-miR-322, mmu-miR-106b, mmu-miR-23a and mmu-miR-15b, and the key down-regulated miRNAs included mmu-miR-16, mmu-miR-30e, mmu-miR-30c, mmu-miR-30a and mmu-miR-130a. CONCLUSION: Differential expression of miRNAs is discovered in mouse fibrotic liver tissues induced by CCl4 compared with the normal liver tissues. Most of the pathological processes involved in liver fibrosis may be regulated by miRNA, such as cell proliferation and activation, cell adhesion and apoptosis, cell migration and differentiation, metabolism, TGF-β receptor signaling pathway and so on.  相似文献   
444.
To evaluate the estrogenic potential of secoisolariciresinol diglycoside (SDG) found in linseed meal (LSM) on visceral organ mass, IGF-I, and thyroid hormone (T3 and T4) concentrations, 48 multiparous, ovariectomized ewes (54.6 ± 1.1 kg) were used in a 3 × 4 factorial arrangement. Main effects were length of LSM feeding (0, 1, 7, or 14 d) and length of exposure to estradiol-17β (E2) implant (0, 6, or 24 h prior to tissue collection). Implanting ewes with E2 for 24 h increased liver mass relative to empty body weight (EBW; g/kg EBW) compared with ewes implanted for 0 or 6 h (P ≤ 0.03), whereas feeding LSM for 14 d decreased liver mass compared with ewes fed LSM for 1 or 7 d (P ≤ 0.02). There was an LSM × E2 interaction (P = 0.01) for duodenal mass (g/kg EBW), LSM, and E2 tended (P = 0.07) to influence the stomach complex mass; however, ileal mass was not affected. Neither LSM nor E2 affected (P ≥ 0.12) CYP2C or CYP3A mRNA expression or cellularity of the liver. Exogenous E2 influenced circulating concentrations of IGF-I, T3, and T4. The estrogenic or anti-estrogenic potential of LSM is dependent upon the tissue, exposure to E2, and the duration of LSM feeding. Feeding LSM during gestation, lactation, or during the grow-finish phase warrants further investigation.  相似文献   
445.
Background: Chronic hepatitis (CH) in dogs is common but little is known about factors associated with survival. Ascites is a well-recognized negative prognostic indicator in humans.
Hypothesis: Ascites is a negative prognostic indicator in CH in dogs.
Animals: Thirty-four dogs with histologically confirmed CH presented to 1 institution between 1996 and 2005.
Methods: Retrospective observational study. CH was diagnosed by histopathology of liver tissue according to the WSAVA criteria. Ascites was diagnosed by abdominal ultrasound. The association of ascites with survival from diagnosis or onset of owner-reported clinical signs until death from any cause or from liver disease was analyzed. Ascitic and nonascitic groups were further analyzed for differences in treatment and sex.
Results: Fourteen of 34 dogs had ascites. Survival from diagnosis to death from liver disease was 0.4 months (95% confidence interval [CI], 0.2–0.6) for ascitic dogs and 24.3 months (CI 11.4–37.1) for nonascitic dogs ( P < .001), and from onset of signs to death from liver disease was 2.0 months (CI 0.0–5.6) for ascitic dogs and 33.0 months (CI 8.6–57.4) for nonascitic dogs ( P = .0020). Diet and spironolactone use differed between groups.
Conclusions and Clinical Importance: Ascites is a significant negative prognostic indicator in dogs with CH. Veterinarians and owners can use this information to aid clinical decision making in affected dogs.  相似文献   
446.
The objective of this study was to determine the effect of increasing levels of molasses on growth performance, carcass characteristics, blood chemistry, liver minerals and histopathology of lambs. Twenty intact male pelibuey lambs with an average weight of 22.4±2.8 kg were randomly assigned to one of the four experimental diets containing 0, 60, 120 and 180 g molasses/kg feed (as fed basis) in a completely random design. Lambs were individually confined to 1.5 m2 pens. The experiment had a 15-day adaptation period and a 60-day experimental period. As molasses content in the ration increased from 0 to 180 g/kg, S increased from 1.1 to 2.1 g/kg DM, whereas Cu concentration ranged from 17.3 to 18.4 mg/kg DM. All diets contained high concentrations of Fe (198–252 mg/kg DM) and Zn (85–104 mg/kg DM), and low Mo contents (1.4–1.5 mg/kg DM). Molasses level had no effect (P>0.05) on DM intake, average daily gain, gain:feed, slaughter weight, full or empty gastrointestinal tract weight, digesta-free weight, hot and chilled carcass weights, dressing percent, longissimus muscle area, marbling, back-fat thickness, yield grade or KPH fat. Most of the lamb carcasses of this study were graded with small to slight marbling. The clinical status of the lambs was evaluated through histological and blood chemistry tests, obtaining samples on days 0, 15, 30 and 60. Although most blood parameters were within normal ranges, blood urea nitrogen, creatinine and cholesterol concentrations decreased (linear; P<0.05) as molasses increased in the diet. Concentrations of the enzymes serum glutamic oxaloacetic transaminase, alkaline phosphatase and creatine phosphokinase were also reduced (linear; P<0.05). Concomitant reductions (P<0.01) in liver Zn and Mo concentrations were also noticed. Although no differences (P>0.05) were observed in liver histopathological observations between treatments, Cu-related sub-lethal hepatic damage was evident in all animals, in absence of clinical signs. Special stain showed fine grained Cu deposits within hepatocytes in three cases belonging to different treatments. It appears that lambs consuming the control diet without molasses with a low S content (0.11%) were as susceptible to a pre-hemolytic copper poisoning (Pre-HCP) as those consuming the other diets containing higher Cu concentrations.  相似文献   
447.
AIM:To investigate the effect of microRNA-100 (miR-100) on the proliferation activity and cell cycle of hepatocarcinoma cells. METHODS:Synthetic miR-100 mimic and its negative control were transfected into human hepatocarcinoma HepG2 cells by liposome method. After transfection, the cell counting kit-8 (CCK-8) was used to measure the cell proliferation activity. The cell cycle distribution was determined by flow cytometry. The expression of Polo-like kinase 1 (Plk1) at mRNA and protein levels was detected by quantitative real-time PCR (qRT-PCR) and Western blotting. RESULTS:The transfection efficiency mediated by cationic liposome was greater than 85%. The inhibitory rates of cell proliferation in HepG2 cells were (43.5±12.2)%, (46.5±3.7)% and (52.1±0.2)% at 24 h, 48 h and 72 h after transfected with miR-100 mimic, respectively, which were significantly increased as compared with the control cells. Moreover, the cell proliferation index in experimental group (35.8 ± 1.4) was higher than that in negative control group (39.2 ± 1.0) and simple liposome group (40.7 ± 2.0) at 72 h. At the same time, the mRNA and protein expression levels of Plk1 obviously decreased in HepG2 cells transfected with miR-100 at 72 h after transfection. CONCLUSION:miR-100 suppresses the proliferation activity of hepatocarcinoma cells by down-regulating Plk1 gene expression.  相似文献   
448.
449.
AIM: To investigate the exacerbating effect of tumor necrosis factor alpha (TNF-α) on lipid accumulation in HepG2 cells by inhibiting liver X receptor alpha (LXRα) signaling pathway. METHODS: Luciferase reporter plasmid driven by the LXRα promoter (pGL3-Basic-LXRα-P) was constructed and transfected into HepG2 cells to detect the LXRα promoter activity. HepG2 cells were incubated with serum-free medium (control), 20 μg/L TNF-α (TNF-α), 100 mg/L LDL (LDL) and 20 μg/L TNF-α plus 100 mg/L LDL (LDL+TNF-α), respectively. The effects of TNF-α on cholesterol accumulation were examined by oil red O staining and quantitative intracellular cholesterol assay. The expression of LXRα, ABCA1 and ABCG1 at mRNA and protein levels was examined by real-time PCR and Western blotting. RESULTS: The pGL3-Basic-LXRα-P was constructed successfully. TNF-α decreased the activity of LXRα promoter in the absence or presence of LDL. Inflammatory stress inhibited the expression of LXRα, ABCA1and ABCG1 at mRNA and protein levels. The cholesterol efflux was increased after loading of LDL, while TNF-α decreased intracellular cholesterol efflux. The results of oil red O staining and quantitative intracellular cholesterol assay demonstrated that inflammatory stress increased cholesterol levels in HepG2 cells. CONCLUSION: TNF-α exacerbates the cholesterol accumulation in hepatic cells via inhibiting LXRα promoter activity and gene expression.  相似文献   
450.
为了观察鸡传染性贫血病(Chicken Infectious Anemia,CIA)免疫对肝脏微粒体苯胺羟化酶活性的影响。20只70日SPF龄白来航蛋鸡随机分为2组,每组10只。免疫组用鸡传染性贫血病弱毒苗免疫4次,每次间隔2周,对照组鸡注射同剂量的生理盐水。最后一次免疫后10 d取肝脏制备微粒体,测定肝微粒体这苯胺羟化酶的活性。结果表明:免疫组鸡苯胺羟化酶的活性为66.034±2.071 nmol/(mg.min),对照组为141.853±19.310 nmol/(mg.min)。与对照组相比,免疫组苯胺羟化酶的活力极显著下降(P﹤0.01)。鸡传染性贫血病免疫可降低肝脏微粒体苯胺羟化酶的活性。  相似文献   
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