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.

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

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.

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.

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.

Objective: To investigate the relationship between plasma level of asymmetric dimethylarginine (ADMA) and coronary artery ectasia in relevant patients. Methods: A total of 72 patients received coronary angiography (CAG) in our hospital were studied and the patients were divided into 3 groups: Coronary ectasia group, Coronary stenosis group and Normal coronary group.n=24 in each group. Plasma levels of ADMA, symmetric dimethylarginine (SDMA) and L-arginine (Arg) were measured by HPLC-MS/MS methods. The relationship between ADMA and CAD was examined by Logistic regression analysis. Results: Plasma level of ADMA in Coronary ectasia group (0.437 ± 0.098) μmol/L and Coronary stenosis group (0.456 ± 0.088) μmol/L were higher than that in Normal coronary group (0.381 ± 0.057) μmol/L,P<0.05. The ratio of Arg/ADMA in Coronary ectasia group (208.54 ± 61.52) and Coronary stenosis group (220.00 ± 104.82) were lower than that in Normal coronary group (254.26 ± 76.22),P<0.05. Logistic regression analysis presented that with adjusted age, gender, smoking, family history of CAD and LDL-C level, and plasma ADMA was still related with CAD (Partial regression coefifcient 9.469, P=0.011). Conclusion: Plasma levels of ADMA were higher in patients with coronary artery ectasia/stenosis than those with normal coronary artery; while ADMA levels were similar between the patients with coronary ectasia and stenosis. Plasma ADMA level was the independent risk factor of CAD.

Objective To identify potential linkage of cholesterol efflux with the expressions of ATP-binding cas-sette receptor A1 (ABCA1), ABCG1 and scavenger receptor B1 (SR-B1) in monocytes derived macrophages of patients with type 2 diabetes mellitus. Methods and Results Blood was collected from subjects with or without type 2 diabetes mellitus. Peripheral blood monocytes were differentiated for 72 hours into macrophages, and cholesterol efflux assays, Real-time quantitative PCR and western blot were performed. Macrophages from patients with type 2 diabetes mellitus showed a reduction in cholesterol efllux. The mRNA and protein expressions of ABCG1 in macrophages from patients with type 2 diabetes mellitus were significantly reduced. In contrast, the expression of ABCA1 and SR-B1 was not significantly different in both control subjects and diabetic patients. In addition, cellular cholesterol efflux from macrophages to autologous serum and pool serum was significantly correlated with the expression of ABCG1. Conclusion ABCG1 expression and cholesterol efflux are reduced in patients with type 2 diabetes mellitus. This impaired cholesterol efflux significantly correlates with decreased expression of ABCG1.

Objective To explore the effect of tert?butylhydroquinone(tBHQ)on ultraviolet B(UVB)?induced oxidative damages in human im?mortalized keratinocytes(HaCaT),and discuss its mechanism. Methods The cultured HaCaT cells were randomly divided into 4 groups:control group(G1),ultraviolet irradiation group(G2),25μmol/L tBHQ pretreatment before ultraviolet irradiation group(G3),and 50μmol/L tBHQ pre?treatment before ultraviolet irradiation group(G4). The content of reactive oxygen species was detected by DCFH?DA method,and the cell prolifera?tion was evaluated by MTT. Western blot was used to measure the protein expression of nuclear factor E2?related factor 2(Nrf2)in both nuclear fac?tions and whole?cell of HaCaT. The mRNA expressions of CAT and SRX were determined by real?time RT?PCR. Results The content of reactive oxygen species in HaCaT cells was increased,and the cell proliferation rate was decreased significantly after ultraviolet irradiation. The pretreatment of 25 and 50μmol/L tBHQ can inhibit the UVB?induced oxidative damage in a dose?dependent manner in HaCaT cells. Compared with G2 group, tBHQ pretreatment could dose?dependently increase the level of Nrf2 protein in nuclear factions and whole?cell of HaCaT,and also the mRNA ex?pressions of CAT and SRX. Conclusion UVB irradiation can induce oxidative stress damages of HaCaT cells. tBHQ may inhibit the UVB?induced oxidative damages through enhancing Nrf2 expressions and nuclear translocation,then activating the transcription of the downstream antioxidant en?zymes CAT and SRX.

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.

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.