Transgene silencing is one of two major obstacles in both basic biomedical research for transgene and clinical practice of gene therapy. Based on the model of HT1080 cell clones, which transduced single copy of retroviral vector MGPN2, the mechanism of transgene silencing was explored in this investigation by a serial molecular techniques. In the HT1080 cell clone that absence of GFP protein synthesized, no significant aberration of epigenetic modification was detected, but the transcript size and the sequence changed that resulted in the reading frame shift. In addition to chromosomal position effect leading to transgene silencing, the transcript reading frame shift associated with retroviral vector rearrangements could induce complete silencing of transgene.
Cell Line, Tumor ; Gene Rearrangement ; Gene Silencing ; physiology ; Genetic Engineering ; Genetic Vectors ; genetics ; Humans ; Retroviridae ; genetics ; metabolism ; Transgenes ; genetics

This study was aimed to construct Sirt1 shRNA interfering vector and to analyze the effects of Sirtl on cell proliferation and apoptosis in HepG2, A549 and 293T cell lines. To design and synthisize Sirtl shRNA sequence then recombinate it to pGenesil-1.0 plasmid, the positive pGenesil-1.0-Sirtl vector clone was screened by effective detections and sequencing. The vectors were transfected into HepG2, A549, 293T cell lines, and Sirtl expression levels in these clones were detected by RT-PCR and Western-blot. These clone cell proliferation activities were detected by MTT, and these cells apoptosis incidences were detected by MTT experiment after treated with DOX. The results showed that Sirt1 shRNA interfering vectors were successfully screened. The levels of Sirtl expression in HepG2-sh, A549-sh and 293T-sh cells were significantly reduced compared with their control cells. It was indicated that the proliferation activities of these cells were impaired and anti-apoptosis capabilities of HepG2-sh, A549-sh and 293T-sh were also impaired notably. Sirt1 took an important role in maintaining cell proliferation and resisting cell apoptosis caused by DNA damage, and this result also provided theoretical information for the further research.
Apoptosis ; genetics ; Cell Line, Tumor ; Cell Proliferation ; Genetic Vectors ; Humans ; RNA Interference ; RNA, Small Interfering ; genetics ; Sirtuin 1 ; genetics ; Transfection

Objective To investigate the reference intervals of lipid metabolism indexes and dyslipidaemia situation among the a-dult of Tibetan in Ganzi County .Methods The serum samples were collected from 661 healthy subjects in Ganzi county ,total cho-lesterol(TC) ,triglyceride(TG) ,high density lipoprotein cholesterol(HDL-C) ,low density lipoprotein cholesterol(LDL-C) ,apoli-poprotein A1(ApoA1) and apolipoprotein B(ApoB) levels were measured .According to the American Society for Clinical Laborato-ry Standards(CLSI) C28-A3 documentation and the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) guidelines for establishing of reference interval with reasonable method and reliable basis ,the interval value of this lipid metabolism indexes were calculated .The dyslipidemia situation was analyzed based on "The Guideline of Prevention and Treatment of Dyslipi-demia in Chinese Adults in 2007".Results In these population ,TG ,LDL-C and ApoB in the serum of male were higher than those of female ,while HDL-C and ApoA1 were lower than those of female ,the difference was statistically significant (P<0 .05) .TC , LDL-C and TG level had a change tendency with ages obviously ,while the changes of HDL-C ,ApoA1 and ApoB metabolism level were not inconspicuous .In this population ,TC ,LDL and ApoB reference intervals were 2 .75 -6 .82 mmol/L ,1 .36 -4 .3 mmol/L and 0 .24-1 .38 mmol/L respectively .The reference interval of TG ,LDL-C and ApoA1 in male population were 0 .5-2 .36 mmol/L ,0 .9-1 .93 mmol/L and 0 .82-1 .87 mmol/L respectively ,meanwhile ,the reference range of TG ,HDL-C and ApoA1 in female population were 0 .47-3 .19 mmol/L ,0 .96-2 .19 mmol/L and 0 .94-2 .02 mmol/L respectively .The incidence of dyslipidemia in Tibetan adults was high ,the incidence of hypercholesterolemia ,hypertriglyceridemia ,mixed hyperlipidemia and low high-density lip-oprotein were 32 .07% ,21 .18% ,12 .86% and 6 .51% respectively .Conclusion In this research ,we established the reference inter-val of blood lipid metabolism indexes of Tibetan adults in Ganzi county and analyzed the incidence of hyperlipidemia in this popula-tion initially .This results provide reference data for clinical intervention treatment of patients with hyperlipidemia in Tibetan popu-lation in Ganzi area ,which is helpful for guiding the prevention and treatment of dyslipidemia in this region .

Objective To investigate the albumin(ALB) and total protein(TP) levels among adult Tibetans with different clinical types of hyperlipidemia in Ganzi County and its correlation with serum liver function in-dexes .Methods The serum was collected from 661 volunteers in Ganzi County .The blood lipid metabolism indexes ,liver function indexes and serum protein levels were measured .The hyperlipidemia was performed the clinical typing according to the Guide on Prevention and Treatment of Chinese Adult Dyslipidemia in 2007 . The statistical analysis was conducted by using the one-way ANOVA variance ,Pearson correlation and multi-ple linear regression analytical methods .Results The hypercholesterolemia group ,hypertriglyceridemia group ,mixed hyperlipidemia group and low high-density lipoprotein hyperlipidemia group had 212 ,140 ,85 ,43 cases respectively ,while 181 cases were in the non-hyperlipidemia .The TP level in the patients with mixed hy-perlipidemia was significantly higher than that in the patients with non-hyperlipidemia ,the difference was sta-tistically significant (P<0 .05) .The liver function indexes ALT ,AST and γ-GGT levels in the hypercholes-terolemia group ,hypertriglyceridemia group and mixed hyperlipidemia group were significantly higher than those in the non-hyperlipidemia group ,the difference was statistically significant (P<0 .05) .The serum pro-tein level was strongly correlated with ALT and AST in the hypertriglyceridemia group and mixed hyperlipi-demia group ,the difference was statistically significant (P<0 .05) .TP serving as the dependent variable and ALB ,ALT and AST as independent variables ,the regression analysis showed TP=25 .149+1 .066(ALB)-0 .158(ALT)+0 .268(AST) in hypercholesterolemia ,TP= 28 .211+ 1 .011(ALB) -0 .067(ALT)+ 0 .176 (AST) in mixed hyperlipidemia and TP=37 .86+0 .79(ALB)-0 .079(ALT)+0 .162(AST) in non-hyperlipi-demia .Conclusion TC and TG can induce the damage of liver function in hyperlipidemia ,ALT and AST are the important indicators affecting serum protein level in the patients with hyperlipidemia .In Tibetan adult population of the Ganzi county ,only the TP level change is noticeably among the patients with mixed hyperlip-idemia ,which may be related with strong compensatory ability of liver function in Tibetan population .

Cardiovascular diseases, including heart failure, coronary artery disease, atherosclerosis, aneurysm, thrombosis, and hypertension, are a great economic burden and threat to human health and are the major cause of death worldwide. Recently, researchers have begun to appreciate the role of microbial ecosystems within the human body in contributing to metabolic and cardiovascular disorders. Accumulating evidence has demonstrated that the gut microbiota is closely associated with the occurrence and development of cardiovascular diseases. The gut microbiota functions as an endocrine organ that secretes bioactive metabolites that participate in the maintenance of cardiovascular homeostasis, and their dysfunction can directly influence the progression of cardiovascular disease. This review summarizes the current literature demonstrating the role of the gut microbiota in the development of cardiovascular diseases. We also highlight the mechanism by which well-documented gut microbiota-derived metabolites, especially trimethylamine N-oxide, short-chain fatty acids, and phenylacetylglutamine, promote or inhibit the pathogenesis of cardiovascular diseases. We also discuss the therapeutic potential of altering the gut microbiota and microbiota-derived metabolites to improve or prevent cardiovascular diseases.