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991.
Hepatic stellate cells (HSCs), a specialized stromal cytotype in the liver, have been demonstrated to actively contribute to hepatocellular carcinoma (HCC) development. However, the previous studies were performed using HSC cell lines, and the prognostic value of intratumoral HSCs (tHSCs) was unclear. Here we isolated tHSCs from fresh human HCC tissues, and analyzed the abilities of tHSCs to promote HCC progression by using in vitro assays for cell viability, migration and invasion as well as epithelial-mesenchymal transition (EMT) phenotype. 252 HCC patients who underwent hepatectomy were enrolled for analysis of tHSCs and E-cadherin expression in tumor tissues, and 55 HCC patients for analysis of tHSCs in tumor tissues and circulating tumor cells (CTCs) in blood. Prognostic factors were then identified. The results showed that coculture of tHSCs with HCC cells had a stronger effect on HCC cell viability, migration and invasion, accompanied with the acquisition of epithelial-mesenchymal transition (EMT) phenotype. In vivo cotransplantation of HCC cells with tHSCs into nude mice more efficiently promoted tumor formation and growth. Icaritin, a known apoptosis inducer of HSCs, was demonstrated to effectively inhibit tHSC proliferation in vitro and tHSC-induced HCC-promoting effects in vivo. Clinical evidence indicated that tHSCs were rich in 45% of the HCC specimens, tHSC-rich subtypes were negatively correlated either with E-cadherin expression in tumor tissues (r = -0.256, p < 0.001) or with preoperative CTCs in blood (r = -0.287, p = 0.033), and were significantly correlated with tumor size (p = 0.027), TNM staging (p = 0.018), and vascular invasion (p = 0.008). Overall and recurrence-free survival rates of tHSC-rich patients were significantly worse than those for tHSC-poor patients. Multivariate analysis revealed tHSC-rich as an independent factor for overall and recurrence-free survival. In conclusion, tHSCs provide a promising prognostic biomarker and a new treatment target for HCC.  相似文献   
992.
The objective of the present study was to systematically explore the effects of 32K Da protein (32KP) on postmenopausal osteoporosis. Eighty 3-mo-old female Sprague-Dawley rats were employed and randomly divided into one sham-operated group (SHAM) and five ovariectomy (OVX) subgroups as OVX (control), OVX with 17-ethinylestradiol (E2, 25 g/kg/day), OVX with 32KP of graded doses (50, 50, or 150 mg/kg/day). 32KP or E2 diet was fed on week 4 after operation, for 16 weeks. Bone mass, bone turnover and strength were evaluated by dual-energy X-ray absorptiometry (DEXA), biochemical markers and three-point bending test, respectively. Femur marrow cavity was observed by light microscopy via hematoxylin-eosin staining. It is observed that different dosage treatment of 32KP increased the body weight and prevented the loss of bone mass induced by OVX. The prevention effect against bone loss was presumably due to the altering of the rate of bone remodeling. The bone mineral density and bone calcium content in OVX rats were lower than that in the control group, suggesting that 32KP was able to prevent significant bone loss. In addition, the data from three point bending test and femur sections showed that 32KP treatment enhanced bone strength and reduced the marrow cavity of the femur in OVX rats. In the serum and urine assay, 32KP decreased urinary deoxypyridinoline and calcium concentrations; however, serum alkaline phosphatase activities were not inhibited. It suggested that amelioration of bone loss was changed via inhibition of bone reabsorption. Our findings indicated that 32KP might be a potential alternative drug for the prevention and treatment of postmenopausal osteoporosis.  相似文献   
993.
Recent advances in nanotechnologies have led to wide use of nanomaterials in biomedical field. However, nanoparticles are found to interfere with protein misfolding and aggregation associated with many human diseases. It is still a controversial issue whether nanoparticles inhibit or promote protein aggregation. In this study, we used molecular dynamics simulations to explore the effects of three kinds of carbon nanomaterials including graphene, carbon nanotube and C60 on the aggregation behavior of islet amyloid polypeptide fragment 22–28 (IAPP22–28). The diverse behaviors of IAPP22–28 peptides on the surfaces of carbon nanomaterials were studied. The results suggest these nanomaterials can prevent β-sheet formation in differing degrees and further affect the aggregation of IAPP22–28. The π–π stacking and hydrophobic interactions are different in the interactions between peptides and different nanoparticles. The subtle differences in the interaction are due to the difference in surface curvature and area. The results demonstrate the adsorption interaction has competitive advantages over the interactions between peptides. Therefore, the fibrillation of IAPP22–28 may be inhibited at its early stage by graphene or SWCNT. Our study can not only enhance the understanding about potential effects of nanomaterials to amyloid formation, but also provide valuable information to develop potential β-sheet formation inhibitors against type II diabetes.  相似文献   
994.
995.
Several single nucleotide polymorphisms (SNPs) of the Glutamate metabotrophic receptor 7 gene (GRM7) have recently been identified by the genome-wide association study (GWAS) as potentially playing a role in susceptibility to age-related hearing impairment (ARHI), however this has not been validated in the Han Chinese population. The aim of this study was to determine if these SNPs are also associated with ARHI in an elderly male Han Chinese population. In this case-control candidate genes association study, a total of 982 men with ARHI and 324 normal-hearing controls subjects were studied. Using K-means cluster analysis, four audiogram shape subtypes of ARHI were identified in the case group: ‘‘flat shape (FL)’’, ‘‘sloping shape (SL)’’, ‘‘2-4 kHz abrupt loss (AL) shape’’ and ‘‘8 kHz dip (8D) shape’’. Results suggested that the SNP rs11928865 (A>T) of GRM7 was significantly associated with ARHI after adjusting for non-genetic factors (p= 0.000472, OR= 1.599, 95%CI= 1.229~2.081). Furthermore, frequency of TT genotype (rs11928865) were significant higher in the SL subgroup and AL subgroup with compared to controls group (p= 9.41E-05, OR= 1.945, 95%CI= 1.393~2.715; p= 0.000109, OR= 1.915, 95%CI= 1.378~2.661 adjusted, respectively) after Bonferroni correction. However, there wasn’t significant difference in the frequency of the TT genotype between cases in the FL subgroup or the 8D subgroup with when compared with controls. Results of the current study suggest that, in an elderly male Han Chinese population, GRM7 SNP rs11928865 (TT) occurs more frequently in ARHI patients with SL and AL phenotype patterns.  相似文献   
996.

Background

With a wide range of applications, titanium dioxide (TiO2) nanoparticles (NPs) are manufactured worldwide in large quantities. Recently, in the field of nanomedicine, intravenous injection of TiO2 nanoparticulate carriers directly into the bloodstream has raised public concerns on their toxicity to humans.

Methods

In this study, mice were injected intravenously with a single dose of TiO2 NPs at varying dose levels (0, 140, 300, 645, or 1387 mg/kg). Animal mortality, blood biochemistry, hematology, genotoxicity and histopathology were investigated 14 days after treatment.

Results

Death of mice in the highest dose (1387 mg/kg) group was observed at day two after TiO2 NPs injection. At day 7, acute toxicity symptoms, such as decreased physical activity and decreased intake of food and water, were observed in the highest dose group. Hematological analysis and the micronucleus test showed no significant acute hematological or genetic toxicity except an increase in the white blood cell (WBC) count among mice 645 mg/kg dose group. However, the spleen of the mice showed significantly higher tissue weight/body weight (BW) coefficients, and lower liver and kidney coefficients in the TiO2 NPs treated mice compared to control. The biochemical parameters and histological tissue sections indicated that TiO2 NPs treatment could induce different degrees of damage in the brain, lung, spleen, liver and kidneys. However, no pathological effects were observed in the heart in TiO2 NPs treated mice.

Conclusions

Intravenous injection of TiO2 NPs at high doses in mice could cause acute toxicity effects in the brain, lung, spleen, liver, and kidney. No significant hematological or genetic toxicity was observed.  相似文献   
997.
Recent studies point to an association between the late-onset sporadic Parkinson’s disease (PD) and single nucleotide polymorphisms (SNPs) rs1559085 and rs27852 in Ca2+-dependent protease calpain inhibitor calpastatin (CAST) gene. This finding is of interest since loss of CAST activity could result in over activated calpain, potentially leading to Ca2+ dysregulation and loss of substantia nigra neurons in PD. We explored the association between CAST SNPs and late-onset sporadic PD in the Han Chinese population. The study included 615 evaluable patients (363 male, 252 female) with PD and 636 neurologically healthy controls (380 male, 256 female) matched for age, gender, ethnicity, and area of residence. PD cases were identified from the PD cohort of the Chinese National Consortium on Neurodegenerative Diseases (www.chinapd.cn). A total of 24 tag-SNPs were genotyped capturing 95% of the genetic variation across the CAST gene. There was no association found between any of the polymorphisms and PD in all models tested (co-dominant, dominant-effect and recessive-effect). Similarly, none of the common haplotypes was associated with a risk for PD. Our data do not support a significant association between the CAST gene polymorphisms and late onset sporadic PD in the Han Chinese population.  相似文献   
998.
Increased serum uric acid (SUA) levels may be involved in the development of non-alcoholic fatty liver disease (NAFLD) in men presenting with metabolic syndrome (MetS) and/or insulin resistance. We aimed to determine the independent relationship between SUA and NAFLD in non-diabetic Chinese male population, and to explore the determinants of SUA levels among indexes of adiposity, lipid, and genotypes pertaining to triglycerides metabolism, inflammation, oxidative stress, and SUA concentrations. A total of 1440 men, classified depending on the presence of ultrasonographically detected NAFLD, underwent a complete healthy checkup program. Genotypes were extracted from our previously established genome-wide association study database. After adjusting for age, smoking, drinking, body mass index, homeostasis model assessment of insulin resistance, C-reactive protein, creatinine, alanine aminotransferase (ALT) and components of metabolic syndrome, the odds ratio for NAFLD, comparing the highest with the lowest SUA quartile, was 2.81 (95% confidence interval 1.66–4.76). A stepwise multivariate linear regression analysis (R2 = 0.238, P<0.001) retained age, waist circumference, serum creatinine, triglycerides, the Q141K variant in ABCG2 (rs2231142) and NAFLD as significant predictors of SUA levels (all P<0.001). Besides, ALT and Met196Arg variant in TNFRSF1B (rs1061622) additionally associated with SUA among individuls with NAFLD. Our data suggest that in Chinese men, elevated SUA is significantly associated with NAFLD, independent of insulin resistance and other metabolic disorders, such as central obesity or hypertriglyceridemia. Meanwhile, among subjects with NAFLD, index of liver damage, such as elevated ALT combined with genetic susceptibility to inflammation associated with increased SUA levels.  相似文献   
999.
The sterile alpha motif (SAM) and HD domain-containing protein-1 (SAMHD1) inhibits the infection of resting CD4+ T cells and myeloid cells by human and related simian immunodeficiency viruses (HIV and SIV). Vpx inactivates SAMHD1 by promoting its proteasome-dependent degradation through an interaction with CRL4 (DCAF1) E3 ubiquitin ligase and the C-terminal region of SAMHD1. However, the determinants in SAMHD1 that are required for Vpx-mediated degradation have not been well characterized. SAMHD1 contains a classical nuclear localization signal (NLS), and NLS point mutants are cytoplasmic and resistant to Vpx-mediated degradation. Here, we demonstrate that NLS-mutant SAMHD1 K11A can be rescued by wild-type SAMHD1, restoring its nuclear localization; consequently, SAMHD1 K11A became sensitive to Vpx-mediated degradation in the presence of wild-type SAMHD1. Surprisingly, deletion of N-terminal regions of SAMHD1, including the classical NLS, generated mutant SAMHD1 proteins that were again sensitive to Vpx-mediated degradation. Unlike SAMHD1 K11A, these deletion mutants could be detected in the nucleus. Interestingly, NLS-defective SAMHD1 could still bind to karyopherin-β1 and other nuclear proteins. We also determined that the linker region between the SAM and HD domain and the HD domain itself is important for Vpx-mediated degradation but not Vpx interaction. Thus, SAMHD1 contains an additional nuclear targeting mechanism in addition to the classical NLS. Our data indicate that multiple regions in SAMHD1 are critical for Vpx-mediated nuclear degradation and that association with Vpx is not sufficient for Vpx-mediated degradation of SAMHD1. Since the linker region and HD domain may be involved in SAMHD1 multimerization, our results suggest that SAMHD1 multimerization may be required for Vpx-mediation degradation.  相似文献   
1000.
Polygonatum odoratum (Mill.) Druce belongs to the genus Polygonatum family of plants. In traditional Chinese medicine, the root of Polygonatum odoratum, Rhizoma Polygonati Odorati, is used both for food and medicine to prevent and treat metabolic disorders such as hyperlipidemia, hyperglycemia, obesity and cardiovascular disease. However, there is no solid experimental evidence to support these applications, and the underlying mechanism is also needed to be elucidated. Here, we examined the effect of the extract of Rhizoma Polygonati Odorati (ER) on metabolic disorders in diet-induced C57BL/6 obese mice. In the preventive experiment, the ER blocked body weight gain, and lowered serum total cholesterol (TC), triglyceride (TG) and fasting blood glucose, improved glucose tolerance test (GTT) and insulin tolerance test (ITT), reduced the levels of serum insulin and leptin, and increased serum adiponectin levels in mice fed with a high-fat diet significantly. In the therapeutic study, we induced obesity in the mice and treated the obese mice with ER for two weeks. We found that ER treatments reduced serum TG and fasting blood glucose, and improved glucose tolerance in the mice. Gene expression analysis showed that ER increased the mRNA levels of peroxisome proliferator-activated receptors (PPAR) γ and α and their downstream target genes in mice livers, adipose tissues and HepG2 cells. Our data suggest that ER ameliorates metabolic disorders and enhances the mRNA expression of PPARs in obese C57BL/6 mice induced by high-fat diet.  相似文献   
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