1.Basic fibroblast growth factor induces the differentiation of human bone mesenchymal stem cells into cardiomyogenic cells in vitro
Lin YANG ; Lianfeng CHEN ; Ti SHEN
Basic & Clinical Medicine 2006;0(05):-
Objective To study the potential of bFGF to promote human bone marrow derived MSCs to differentiate into cardiomyogenic cells, and its effect on proliferation of MSCs. Methods MSCs isolated from adult human bone marrow were cultured in four different systems. Group A: medium with 5-aza. Group B: medium with bFGF. Group C: medium with 5-aza+bFGF. Control group: medium alone. The morphological changes of MSCs were observed. Then immunocytochemistry staining against ?-actin,cTnT,and Connixin43 was performed. The expression of Nkx2.5, GATA-4 and cTnT was detected by semi-quantitative RT-PCR. The proliferation of MSCs in different groups was measured by MTT. Results The MSCs in both group A and C partially differentiated into myogenic cells and expressed proteins of ?-actin,cTnT,and connixin43. In group A and group C, the mRNA level of Nkx2.5,GATA-4 and cTnT was higher than that of control group. In group B, mRNA level of Nkx2.5 and GATA-4 was higher than that of control group. As compared with the control group, cell proliferation was faster in group B than in group A and C. And the proliferation was faster in group C than in group A. Conclusion bFGF can promote the proliferation of MSCs significantly. When combining with 5-aza, bFGF can promote MSCs to differentiate into cardiomyogenic cells more effectively.
2.Simvastatin for lung fibroblast function and its inhibitory pathway in rats
Jicheng XI ; Qingyu WU ; Lianfeng CHEN
Chinese Journal of Tissue Engineering Research 2005;9(19):200-202
BACKGROUND: Statins can block many intracellular signal transductive pathways and suppress the proliferation of various cells by affecting the synthesis of mevalonic acid and the translation following modification of some membrane-connecting proteins.OBJETCIVE: To investigate the influence of simvastatin on the proliferation of lung fibroblasts, the synthesis of collagen and the secretion of matrix metalproteinase-2 (MMP-2).DESIGN:Completely randomized controlled study.SETTING: At Organ Transplanting Research Institute of Fuwai Cardiovasular Diseases Hospital, Peking Union Medical College.MATERIALS: This study was carried out at the Laboratory of Cardiology of Beijing Union Medical College hospital, Peking Union Medical College from June 2004 to October 2004. Lung fibroblasts derived from neonatal SD rats were co-cultured in vitro with different dosage of simvastatin of 0, 1, 5, 10,50 μmol/L, and 50 μmol/L simvastatin + 200 μmol/L mevalonic acid.METHODS: Lung fibroblasts deriving from neonatal SD rat were co-cultured with different dosage of simvastatine in vitro. Methyl thiazolyl tetrazolium colorinetry was used to detect the cell proliferation, and cell immunohistochemical assay was used to determine the collagen synthesis and meanwhile,MMP-2 content in supernatant was examined with enzyme-linked immunosorbent assay.MAIN OUTCOME MEASURES: The proliferation of fibroblasts, the synthesis of collagen and the secretion of MMP-2 due to different dosage of simvastatin intervention and simvastatin combined with mevalonic acid.presenting the expression of type Ⅰ, Ⅲ of collagen in lung fibroblasts and the level of MMP-2 in 5, 10, 50 μmol/L simvastatin group were obviously lower than those of 0 μmol/L simvastatin group (0. 520 ± 0.010, 0. 334 ± 0.011,0.260±0.012, 0.111±0.011; 0.508±0.011, 0.324±0.014, 0.232±0.015, 0. 083 ±0. 015; 0.445 ±0. 017, 0. 305 ±0. 015, 0.216 ±0. 015,0.068±0.012; 0.561±0.013, 0.361 ±0.012, 0.289±0.012, 0.140value, the mean absorbency( A value) in lung fibroblasts and the level of MMP-2 in 50 μmol/L simvastatin + 200 μmol/L mevalonic acid group were obviously higher than that of the 50 μmol/L simvastatin group(0. 567±0.015, 0.354±0.014, 0.283±0.012, 0.138±0.011, t=4.715-10.950, P < 0.01).CONCLUSION: Simvastatin could suppress the fibroblast proliferation and collagen synthesis, attenuate the secretion of MMP-2 and suppress consequently the adhesion and migration of lung fibroblasts; moreover, it has the capability of anti-cell proliferation by affecting the mevalonic acid pathway.
3.Effect of myocardial microenvironment on the differentiation of bone marrow mesenchymal stem cells
Yan YUAN ; Lianfeng CHEN ; Shuyang ZHANG
Chinese Journal of Interventional Cardiology 2003;0(05):-
Objective In this study, we try to understand the effects of microenvironment on the differentiation of mesenchymal stem cells (MSCs) by coculturing MSCs with mature cardiomyocytes or culturing MSCs in cardiomyocyte-lysate, in this study. Methods MSCs isolated from mature rats were either cocultured with cardiomyocytes isolated from new born rats with the ratio of 1 to 4, or cultured in the medium containing 4-fold cardiomyocyte-lysate obtained by repeated freezing and defrosting of rat myocardial cells. The morphology of MSCs under light microscopy were observed daily for 7 days and immunostaining against cTnT and CD31 was performed on the 7~ th day. MSCs cultured in ordinary medium were observed as the control. Results Both MSCs cocultured with cardiomyocytes and cultured in cardiomyocyte-lysate were differentiated into myogenic cells and expressed cTnT and CD31 at the 7th day of cultivation. The MSCs in the control group did not change in morphology and express cTnT or CD31. Conclusion Both myocardial cell coculturing system and cardiomyocyte-lysate system can be used to induce bone marrow MSCs to differentiate into cardiomyocyte-like cells and endotheliocyte-like cells.
4.Effect of MMT on reducing the transmission of HIV among IDUs
Huaxian HE ; Yugang BAO ; Lianfeng CHEN
Chinese Journal of AIDS & STD 2006;0(02):-
Objective To study the effect of methadone maintenance treatment(MMT) on reducing HIV infection among injecting drug users(IDUs) in Yueyang city of Hunan province.Methods Local IDUs were provided with MMT along with peer education and behavior interventions,and they were tested for HIV antibody to evaluate the effect of MMT after one year treatment.Results Of the 113 IDUs who were negative at the entry,none turned to be positive after one year treatment and the negative partners of 22 IDUs with positive HIV antibody remained negative one year later,and the negative rate of urine test maintained at 76.10%.Conclusion MMT combined with peer education and behavior interventions will decrease the use of heroin,prevent HIV infection among IDUs and reduce their partners' susceptibility to HIV.
5.Study on the relationship between copper, lysyl oxidase and premature rupture of membranes
Huidan ZHANG ; Huichi CHEN ; Lianfeng SHAN
Chinese Journal of Obstetrics and Gynecology 2001;0(01):-
Objective To determine the relationships between maternal serum copper,amniotic copper,lysyl oxidase (LOX) and collagen Ⅲ in pregnant women with premature rupture of membranes (PROM) and without PROM.Methods One hundred women with PROM were enrolled in this study,and divided into 37-42 weeks,34-36~ +6 weeks and 28-33~ +6 weeks according to gestational age. One hundred non-PROM pregnancies matching the same gestational ages were recruited as control group. Copper of maternal serum and amnion in two groups were compared by FAAS method. Amniotic LOX was analyzed by fluorometry. Amniotic collagen Ⅲ was detected by immunohistochemical method and computer image analysis system(absorbance,A). Linear correlation analysis was used to explore the relationships between maternal serum copper,amniotic copper,LOX and collagen Ⅲ. Results (1)For 37-42 weeks pregnant women,serum copper was correlated positively with amniotic copper in two groups, r= 0.82(P0.05),but amniotic LOX and collagen Ⅲ decreased significantly compared with controls, being [(0.53?0.10)?g/g vs (0.75?0.10)?g/g,P
6.Establishment of APPswe/PS1 dE9/TAU triple transgenic rat model of alzheimer disease
Li ZHANG ; Wei CHEN ; Xu ZHANG ; Caixian SUN ; Lianfeng ZHANG
Chinese Journal of Comparative Medicine 2014;(3):61-65,66
Objective To develop a model that could roundly show the phenotypes of human alzheimer disease (AD), the triple-transgenic rat model harboring APP(Swe), PS1dE9, and TAU transgenes was established in view of the advantage of rat as an important animal model on the research of nerve system .Methods APPswe/PS1dE9/TAU triple transgenic rat AD rats were generated on a SD background by co-injecting rat pronuclei with two human genes driven by the mouse prion promoter:‘Swedish’ mutant human APP (APPsw) and exon 9 mutant human presenilin-1 (PS1dE9) and human microtubule-associated protein tau gene under the control of PDGF promoter .Transgene integration was confirmed by genotyping and expression levels were evaluated by western blot ( WB ) of brain homogenates .The pathological changes were detected by human Abeta, TAU and Phospho-PHF-TAU immunohistochemistry staining (IHC).The behavioral and cognitive changes were evaluated by Morris water maze .Results One transgenic rat lines with high human APP ( Swe ) , PS1dE9, and TAU transgenic expression was selected from three transgenic founders .Compared with the wild type rat , the transgenic rat showed significant learning and memory impairments in the Morris water maze at 6 months of age .The triple transgenic rat manifested hyperphosphorylated tau and obvious aggregation of amyloid -β( Aβ) in the brain cortex and hippocampus.Conclusion APPswe/PS1dE9/TAU triple transgenic rat AD model was established .The triple transgenic AD rat fills a critical need for a next-generation animal model to enable basic and translational AD research .
7.Differentiation of rats bone marrow mesynchymal stem cells into cardiomyogenic cells with pacemaking function
Xin WEI ; Lianfeng CHEN ; Bojiang LIU ; Quan FANG
Basic & Clinical Medicine 2006;0(10):-
Objective To find the way of inducing the bone marrow mesynchymal stem cells(MSCs)into cardiac cells with pacemaking function in vitro.Methods Dissociate the rat MSCs and induce them with 5AZA,bFGF+EGF,HGF,SCF and lysate of the sinoatrial cells respectively.The morphological changes were observed,and the expressing of protein cTnT,connexin 43 and HCN2/4 were analyse by immunohistologic and flowcytometry techniques.The pacmaking current If were evaluted by patch clamp techniques.Results All the methods can induce the bone marrow MSCs to differentiate into cardiac cells,which expressing cardiac cell specific protein and HCN2.Cells induced by 5AZA,bFGF+EGF and SAN CMs show higher rate of HCN2 expressing(22.9%,22.3%,11%).The cells of these groups have the pacmaking current If.Conclusion Lysate of the sinoatrial cells are ideal methods of inducing the bone marrow MSCs to differentiate into cardiac cells with pacemaking function in vitro.HCN is a promising marker protein to select pacmaking cells out of the differentiated cells.
8.Enterococcus faecium: Its Clinical Distribution and Drug Resistance
Haixia HUANG ; Qing WU ; Lijiang CHEN ; Lianfeng WU
Chinese Journal of Nosocomiology 2006;0(08):-
OBJECTIVE To investigate the clinical distribution and antibiotic resistance of Enterococcus faecium in our hospital and provide the reference for the clinical treatment. METHODS The statistical method was used to analyze the status of drug resistance of 519 E. faecium strains which were isolated form our hospital from Jun 2006 to May 2008. RESULTS Among 519 isolated E. faecium strains, most common sources of specimens were urine (34.9%), sputum(26.8%) and feces (18.3%); E. faecium infection mainly distributed at ICU, respiratiory wards and EICU; E. faecium was resistant to multiple antibiotics. The drug-resistant rates to vancomycin and teicoplanin were 6.2% and 3.2%, respectively. CONCLUSIONS E. faecium could cause various infection, and has a high antibiotic resistance which is difficult to treat, we should be paid high clinical attention.
9.Effects of high-density lipoprotein and lipoprotein-deficient serum on intracellular cholesterol efflux in patients with type 2 diabetes mellitus
Huijuan WANG ; Xiaomei MENG ; Lianfeng CHEN ; Quan FANG ; Xiaowei YAN
Basic & Clinical Medicine 2006;0(05):-
Objective To examine the effects of high-density lipoprotein(HDL) and lipoprotein-deficient serum(LPDS) isolated from patients with type 2 diabetes mellitus on cholesterol efflux through human skin fibroblast(HSF) and human hepatoma cell line(HepG2).Methods and Results Blood was collected from 13 patients with type 2 diabetes mellitus and 17 healthy volunteers,HDL and LPDS were isolated.Cholesterol efflux assays,RT-PCR and Western blot were performed with HSF and HepG2 cells.The HepG2 cells showed a high expression of scavenger receptor B1(SR-B1) and lack of functional ATP-binding cassette receptor A1(ABCA1) and ATP-binding cassette receptor G1(ABCG1) while HSF cells express SR-B1 at very low level and have a high expression of ABCA1 pretreated with 22-OH cholesterol.The cholesterol efflux from HepG2 cells to HDL isolated from patients with diabetes decreased significantly as compared to controls.However,cholesterol efflux from HSF cells to LPDS was not different between groups.Conclusion The function of HDL involving cholesterol efflux in type 2 diabetes mellitus was impaired while cholesterol efflux induced by LPDS from HSF cells was maintained,suggesting that HDL plays a critical role in mediation of intracellular cholesterol accumulation and progression of atherosclerosis inpatients with type 2 diabetes.
10.Surveillance on MIC of Antibiotic Resistance of Meticillin-resistant Staphylococcus aureus
Lijiang CHEN ; Tieli ZHOU ; Qing WU ; Meina LIU ; Lianfeng WU
Chinese Journal of Nosocomiology 2005;0(11):-
OBJECTIVE To review and analyze the change in the MICs of vancomycin,teicoplanin and linezolid in meticillin-resistant Staphylococcus aureus(MRSA) strains isolated in our hospital from 2003 to 2007. METHODS The MICs of vancomycin,teicoplanin and linezolid were tested by Etest method on a sample of randomly selected MRSA strains. RESULTS The incidences of MRSA increased from 52.2% in 2003 to 74.5% in 2007.MIC of vancomycin increased from 1.85 ?g/ml in 2003 to 2.15 ?g/ml in 2007,and teicoplanin MIC geometric mean increased even more markedly from 1.28 ?g/ml in 2003 to 2.07 ?g/ml in 2007.The linezolid MIC remained almost unchanged. CONCLUSIONS The incidences of MRSA were increasing from 2003 to 2007.There is a upward trend in MIC of glycopeptide over the years,in which the increase for teicoplanin is higher than others two.