1. Effect of ART 1 gene silencing by RNA interference on the proliferation of mouse colon carcinoma cells and its possible mechanism
Tumor 2012;32(12):949-954
Objective: To investigate the effect of ART 1 (arginine-specific adenosinediphosphateribosyltransferase 1) gene silencing by shRNA (short hairpin RNA) interference on the proliferation ability of mouse colon cancer CT26 cells, and to explore its possible mechanism. Methods: It was confirmed that ART1 expression existed in CT26 cells by immunofluorescence assay. Lentivirus of ART1-shRNA was infected into mouse colon carcinoma CT26 cells. The CT26 cells uninfected or infected with a negative NC-shRNA (control-shRNA) served as the controls. The expression of ART1 mRNA was detected by RTPCR, and the expressions of ART1, RhoA, c-myc, and c-fos proteins were examined by Western blotting. The cell proliferation in each group was measured by CCK8 (cell counting kit-8) assay. Results: It was determined that ART1 expression existed in the CT26 cells. Lentivirus of ART1-shRNA or NC-shRNA was infected into CT26 cells successfully, and the CT26 cell line with stable low-expression of ART1 was successfully established. Compared with CT26 cells infected with NC-shRNA lentivirus or those were un-infected, the expression of ART1 mRNA was significantly reduced in CT26 cells infected with ART1- shRNA lentivirus (P < 0.01), and the protein expression levels of ART1, RhoA, c-myc, and c-fos were all obviously decreased (P < 0.01). The inhibition rate of cell proliferation of CT26 cells infected with ART1-shRNA lentivirus was markedly increased compared with the control groups (P < 0.01). Conclusion: RNA interference targeting ART 1 gene can inhibit the proliferation ability of mouse colon carcinoma CT26 cells. This effect probably associates with the down-regulation of the expressions of RhoA and its downstream effectors c-myc and c-fos after silencing the expression of ART 1 gene. Copyright © 2012 by TUMOR.
3.Electromechanical delay is a key to neuromuscular transmission
Ziwen PEI ; Xia XU ; Jian CHEN
Chinese Journal of Tissue Engineering Research 2017;21(24):3931-3936
BACKGROUND:With the development of sports medicine and rehabilitation medicine, electromechanical delay has been looked as an important index for evaluating the neuromuscular function at abroad. But the relevant research is little reported in China. OBJECTIVE:To review the literatures related to electromechanical delay published in recent years, and to explore the mechanisms, influential factors and the application status of the electromechanical delay, thereby providing reference for clinical practice and research. METHODS:A computer-based search of CNKI, WanFang and PubMed databases was performed for articles addressing electromechanical delay published from February 1979 to February 2017. The keywords were electromechanical delay, electro-mechanical response time in English and Chinese, respectively.Repeated and old studies were excluded, and finally 44 eligible literatures were included, including 3 Chinese and 41 English articles. RESULTS AND CONCLUSION: The mechanisms of electromechanical delay have been clarified. The type of muscle fiber and the level of muscle fatigue can influence electromechanical delay, but the underlying mechanisms still remain unclear. Whether age and gender make effect on electromechanical delay is controversial. Electromechanical delay is not only used for evaluating the athletes' ability to reaction, but also wildly used to investigate the mechanism of various sports injuries and evaluate the effectiveness of rehabilitation.
4.Effect of fibroblast growth factor receptors 1-dominant negative strategy on alkaline phosphatase activity of bone marrow stromal cells after osteogenic induction
Xia LI ; Wenmang XU ; Hong JIAN ; Yongqing XU ; Fubing LI
Chinese Journal of Orthopaedic Trauma 2016;18(6):526-531
Objective To explore the effect of fibroblast growth factor receptors 1-dominant negative strategy (FGFR1-DN) on alkaline phosphatase (ALP) activity of bone marrow stromal stem cells (BMSCs) after osteogenic induction.Methods BMSCs were transfected with eukaryotic expression plasmid pcDNA 3.1 (+)-DN FGFR1 and pcDNA3.1 (+)-FGFR1.The experiment was conducted in 4 groups:FGFR1-DN transfection group,FGFR1 transfection group,pcDNA3.1(+) empty vector transfection group and non-transfection group.The ALP activity of BMSCs was detected in logarithmic growth phase after osteogenic culture.The qualitative detection of ALP activity was carried out immunohistochemically while the quantitative detection by cALP kit.The ALP activity was compared between the 4 groups at 7 and 14 days after osteogenic induction.Results Compared with 7 days,the ALP activity at 14 days was significantly increased in the 4 groups,and the increase in FGFR1-DN transfection group was significantly higher than in the other 3 groups (P < 0.05).At both 7 and 14 days,the ALP activity in FGFR1-DN transfection group was the highest while that in FGFR1 transfection group was the lowest (P < 0.05).Conclusions FGFR1-DN can promote the ALP activity of BMSCs during osteogenesis.This may provide an experimental basis for the joint application of local gene therapy and tissue engineering and for construction of tissue engineered bone with better biocompatibility.
9.Positive alarming time of blood culture and distribution of pathogens
Quan XU ; Siyuan TAN ; Zongning CHEN ; Jian WU ; Xiaoyan XIA
Chinese Journal of Infection Control 2017;16(2):173-175,178
Objective To investigate the distribution of pathogens and positive alarming time of blood culture,and provide basis for laboratory diagnosis and clinical treatment. Methods Blood specimens from clinical departments in a hospital in May-November 2015 were collected,positive alarming time of blood culture was recorded,species of pathogens were identified. Results A total of 157 pathogenic strains were isolated from blood culture specimens, gram-positive cocci,gram-negative bacilli,and fungi accounted for 31 .85% ,57.32% ,and 10.83% respectively. The median positive alarming time were as follows:Enterobacteriaceae 0.50 day,non-fermenting bacteria 0.63 day, Enterococcusspp. 0.60 day,Streptococcusspp. 0.80 day,Staphylococcusspp. 1.01 days,and fungi 1.44 days, respectively. Conclusion Positive alarming time of blood culture specimens from early to late are as follows:Enter-obacteriaceae,Enterococcus,non-fermentative bacteria,Streptococcus spp.,Staphylococcus spp.,and fungus. Positive alarming time of pathogens causing bloodstream infection are all within 4 days,and most of them are within 1 day.
10.Effect on the Content of Peoniflorin in Radix Paeoniae Alba for Different Storing Time after Harvesting.
Xia WAN ; Kangkang XU ; Jian WU ; Xiaoqing TANG ; Kangcai WANG ;
Journal of Medical Research 2006;0(10):-
Objective To determine the content of paeoniflorin with different medicinal parts in Radix Paeoniae Alba and offer a reference for collection and processing. Methods The content of paeoniflorin was measured by HPLC method. Combining air drying with weight relief condition, the content of paeoniflorin was calculated in fresh Radix Paeoniae Alba. Results There was the highest content of paeoniflorin in Radix Paeoniae Alba in 24~48 hours after collection, and the another increasing of the content was founded 120 hours after collection. Conclusion Radix Paeoniae Alba should be processed in 48 hours after collection.