Objective To assess the therapeutic effect and safety of radiofrequency catheter ablation of atrial fibrillation.Methods We analyzed the clinical data of 47 patients with atrial fibrillation who underwent radiofrequency catheter ablation between March 2013 and January 2008,in the First Affiliated Hospital of Xi'an Jiaotong University.In the average 32 months’follow-up,Holter monitering and echocardiography were reviewed for the left atrial diameter.Results The immediate success rate of catheter ablation for atrial fibrillation was 82.6%.The long-term success rate was 65%,the rate of paroxysmal atrial fibrillation was 69.7%,and the rate of longstanding persistent atrial fibrillation was 42.9%.After ablation,the left atrial diameter were markedly reduced compared with that before treatment [(36.3 ± 4.3 )mm vs .(38.1 ± 5.9 )mm)(P < 0.001 ).The patients with recurrent atrial fibrillation were older than those without recurrence,their left atrial diameter was bigger,and the prevalence rate of hypertension was higher (P <0.05).The average atrial fibrillation load was 14.9% after ablation compared with 46.1% before (P <0.05).Conclusion Radiofrequency catheter ablation is an effective and safe treatment of atrial fibrillation,especially for paroxysmal atrial fibrillation.The left atrial diameter was significantly decreased after radiofrequency catheter ablation compared with that before the ablation.

OBJECTIVE To investigate the prevalence of multidrug resistance(MDR) mechanisms of Staphylococcus haemolyticus against oxacillin,gentamycin and erythromycin.METHODS Agar dilution method was performed to detect the minimal inhibition concentration(MIC) of 3 antimicrobial agents against 63 strains of S.haemolyticus,and the resistance genes of mecA,aac(6′)+aph(2″),ermA,ermB,ermC and msrA/msrB were investigated by PCR in all clinical isolates.RESULTS mecA Gene was detected in 62 isolates of meticillin-resistant S.haemolyticus(MRSH),and aac(6′)+aph(2″) gene was found in 50 isolates resistant to gentamicin,and the most prevalence erythromycin resistance gene in S.haemolyticus was msrA/msrB(58.7%),followed by ermC(31.7%).Among the 43 MDR strains,the more commonly encountered three genes were mecA,aac(6′)+aph(2″) and msrA/msrB(58.1%)or ermC(20.9%),and 8 isolates(18.6%) were found harboring four genes of mecA,aac(6′)+aph(2″),ermC and msrA/msrB.CONCLUSIONS The mecA,aac(6′)+aph(2″),msrA/msrB and ermC genes are main resistance mechanisms against oxacillin,gentamicin and erythromycin in mutidrug resistant S.haemolyticus.

OBJECTIVE To investigate the susceptibilities of Staphylococcus aureus and Enterococcus isolated from Shenzhen Hospital during 2005 to 2006 to 17 antimicrobial agents.METHODS The minimal inhibitory concentrations(MICs) of 17 antibacterial agents were determined by agar dilution method,WHONET5.3 software was used to analyze the data.RESULTS The prevalence of meticillin-resistant S.aureus(MRSA) was 20.7%.Vancomycin and teicoplanin remained very high activity against MRSA(100%),with the MIC50 and MIC90 of 0.5 and 1 ?g/ml,respectively.Fluoroquinolones(ciprofloxacin,levofloxacin and gatifloxacin),trimethoprim/sulfamethoxazole,erythromycin,and clindamycin showed very low activity against MRSA(0-33.3%).The most active agent against Enterococcus faecalis was vancomycin and teicoplanin(100.0%),followed by piperacillin/tazobactam,imipenem and ampicillin(97.2-100.0%).E.faecium showed high resistance to various agents,except to vancomycin and teicoplanin(susceptible rate 100.0%).Cross-resistance to fluoroquinolones was found among MRSA,MSSA,E.faecalis,and E.faecium.CONCLUSIONS MRSA and E.faecium isolated from our hospital showed high resistance to multiple antimicrobial agents except vancomycin and teicoplanin.

OBJECTIVE To investigate the antimicrobial susceptibility of 9 antimicrobial agents and multidrug(resistance)(MDR) phenotype among Acinetobacter baumannii isolated from hospitalized patients.METHODS Disk diffusion method was used to detect the inhibitory zone diameter of 9(antimicrobial) agents to 221 strains of A.baumannii.according to standard from NCCLS in South China during 2002 to 2004.RESULTS 25.3% and 26.4% of isolates from ICU patients showed resistance to(imipemem) and meropemem,respectively,and the resistance rates were greater among the(isolates) from ICU(patients) than those from non-ICU inpatients by 13.4% and 12.2 %(P

Thiamin pyrophosphate (TPP) is a thiamine (vitamin B1) derivative and an essential cofactor in oxidative metabolism of the sugars,fatty acids and amino acids in living cells.By now,numerous TPP-dependent artificial riboswitch systems have been developed to regulate target gene expression but limited in bacteria,fungi or plant cells.Herein,the activating (switch-on) and inhibiting (switch-off) TPP-depended hammerhead ribozyme switches,which are from previous reported structures of prokaryotes screening,were investigated in mammalian cells.These ribozyme switches were inserted into the 3'UTR of the enhanced green fluorescence protein (EGFP) gene to construct the efficient ribozyme-based artificial switches through overlap extension PCR cloning.The HEK293 cells were transfected with the engineered ribozyme switches at increasing concentration of TPP.The EGFP gene-regulatory ability was analyzed with fluorescent microscope and flow cytometry.These TPP-inducible gene regulation devices showed the obvious ligand dose-dependency and excellent specificity.Two switch-on and one switch-off constructs demonstrated 3.1-fold or 1.9-fold increment and 2.3-fold reduction of EGFP level respectively with 150 μ mol/L TPP.The ligand-responsive ribozyme switches,by tuning the change of TPP concentration into the visual reporter genetic expression in cells,enable an efficient development of label-free,noninvasive and high-specific biosensors in living mammalian cells.

Objective To reveal the role of serum ACE2/Ang (1-7)in the occurrence of atrial fibrillation (AF)and find new targets for the prevention and treatment of AF by analyzing the correlation between the serum concentration of ACE2/Ang (1-7 )in patients with rheumatic valvular heart disease and the occurrence of AF. Methods We collected the basic clinical information and peripheral venous blood of patients with rheumatic heart valve disease (totally 46 patients,including 24 with AF and 22 with SR).ELISA method was used to detect the serum concentration of ACE2,Ang (1-7)and AngⅡ in the serum samples.Then the differences and correlation between the two groups were analyzed.Results In the AF group ① the diameter of the left atrium was significantly greater than that in the SR group [(60.70±3.08 vs.48.15±2.16)mm,P<0.05];② the serum concentration of AngⅡ was significantly higher than that in the SR group [(45.88±2.87 vs.35.78±1.08)pg/mL, P<0.05],AngⅡ and left atrium diameter were positively correlated (Pearson test,P<0.05);③ the serum concentrations of ACE2 [(7.87±0.74 vs.11.65±0.57)U/L,P<0.05]and Ang (1-7)[(146.05±17.61 vs. 321.71±36.50)pg/mL,P<0.05]were significantly lower than those in the SR group,and negatively correlated with left atrium diameter (Pearson test,P<0.05);④ the serum concentration of Ang (1-7)was negatively correlated with AngⅡ concentration (Pearson test,P<0.05).Conclusion For patients with rheumatic valvular heart disease,ACE2/Ang (1-7 )may play a protective role in the occurrence of AF via antagonizing AngⅡ and inhibiting atrial remodeling.

Objective To assess the effectiveness and safety of radiofrequency catheter ablation for idiopathic ventricular arrhythmia in patients with idiopathic ventricular arrhythmia after radiofrequency catheter ablation treated in the First Affiliated Hospital of Xi’an Jiaotong University based on the follow-up and retrospective analysis.Methods We retrospectively analyzed the clinical data of 63 patients with idiopathic ventricular arrhythmia who underwent radiofrequency catheter ablation during January 2008 and March 2014 in the First Affiliated Hospital of Xi’an Jiaotong University.In the follow-up,Holter moniterings were reviewed to evaluate ventricular arrhythmia and echocardiography to assess the ejection fractions and left ventricular end-diastolic diameters.Results The immediate success rate of catheter ablation for the treatment of idiopathic ventricular arrhythmia was 89.29% and the long-term success was 82.14%.The ejection fractions and left ventricular end-diastolic diameters were not obviously improved after radiofrequency ablation (P > 0.05 ). The ventricular premature contractions were significantly reduced after radiofrequency ablation (P <0.05).In postoperative care, one case was found with ruptured sinus valsalva tumor and another patient was found with the complication of hematoma in femoral artery puncture.Conclusion Radiofrequency ablation for idiopathic ventricular arrhythmia is safe and effective.

Betulinic acid (BA), a pentacyclic lupane-type triterpene, has a wide range of bioactivities. The main objective of this work was to evaluate the hepatoprotective activity of BA and the potential mechanism underlying the ability of this compound to prevent liver damage induced by alcohol in vivo. Mice were given oral doses of BA (0.25, 0.5, and 1.0 mg/kg) daily for 14 days, and induced liver injury by feeding 50% alcohol orally at the dosage of 10 ml/kg after 1 h last administration of BA. BA pretreatment significantly reduced the serum levels of alanine transaminase, aspartate transaminase, total cholesterol, and triacylglycerides in a dose-dependent manner in the mice administered alcohol. Hepatic levels of glutathione, superoxide dismutase, glutathione peroxidase, and catalase were remarkably increased, while malondialdehyde contents and microvesicular steatosis in the liver were decreased by BA in a dose-dependent manner after alcohol-induced liver injury. These findings suggest that the mechanism underlying the hepatoprotective effects of BA might be due to increased antioxidant capacity, mainly through improvement of the tissue redox system, maintenance of the antioxidant system, and decreased lipid peroxidation in the liver.
Animals ; Antioxidants/pharmacology ; Blood Chemical Analysis ; Enzymes/blood ; Ethanol/*toxicity ; Lipid Peroxidation/drug effects ; Liver/*drug effects/enzymology/metabolism/pathology ; Male ; Mice ; Random Allocation ; Triterpenes/*pharmacology

Objective To analyze the pathogens distribution and drug resistance of nosocomial infection in patients with end-stage diabetic nephropathy .Methods 96 cases of end-stage diabetic nephropathy were randomly selected in our hospital .The speci-mens of urine ,blood and sputum were collected .The pathogens were identified by the drug susceptibility testing .Results The in-fection rate was 27 .08% .A total of 103 strains of pathogens were isolated ,including 15 strains of fungi ,42 strains of gram-negative bacteria and 46 strains of gram-positive bacteria .The drugs susceptibility rates of the fungi to flucytosine ,amphotericin B and flu-conazole were 100% ,and it also showed that the fungi had higher sensitivity to other common antibiotics ;the drug susceptibility rates of gram-positive bacteria to vancomycin and teicoplanin were 100% ,while its drug susceptibility ability to penicillin ,strepto-mycin and others were weak ;the drug susceptibility rates of gram-negative bacteria to piperacillin and imipenem were high ,while its drug susceptibility ability to aztreonam and cephalosporin were weak .Conclusion The low resistance in the patients with end-stage diabetic nephropathy the abuse of clinical antiseptic drugs lead to the dysbacteriosis ,resulting in a significant increase of the inci-dence of nosocomial infection ,so the analysis of pathogens distribution and drug resistance of nosocomial infection has clinical sig-nificance .

To investigate the effects of gossypol acetic acid (GA) on proliferation and apoptosis of the macrophage cell line RAW264.7 and further understand the possible underlying mechanism responsible for GA-induced cell apoptosis, RAW264.7 cells were treated with GA (25~35 micromol/L) for 24 h and the cytotoxicity was determined by MTT assay, while apoptotic cells were identified by TUNEL assay, acridine orange/ethidium bromide staining and flow cytometry. Moreover, mitochondrial membrane potential (DeltaPsi(m)) with Rhodamine 123 and reactive oxygen species (ROS) with DCFH-DA were analyzed by fluorescence spectrofluorometry. In addition, the expression of caspase-3 and caspase-9 was assessed by Western Blot assay. Finally, the GA-induced cell apoptosis was evaluated by flow cytometry in the present of caspase inhibitors Z-VAD-FMK and Ac-LEHD-FMK, respectively. GA significantly inhibited the proliferation of RAW264.7 cells in a dose-dependent manner, and caused obvious cell apoptosis and a loss of DeltaPsi(m) in RAW264.7 cells. Moreover, the ROS production in cells was elevated, and the levels of activated caspase-3 and caspase-9 were up-regulated in a dose-dependent manner. Notably, GA-induced cell apoptosis was markedly inhibited by caspase inhibitors. These results suggest that GA-induced RAW264.7 cell apoptosis may be mediated via a caspase-dependent mitochondrial signaling pathway.
Animals ; Antineoplastic Agents, Phytogenic/*pharmacology ; Apoptosis/*drug effects ; Cell Line ; Cell Proliferation/*drug effects ; Dose-Response Relationship, Drug ; Gossypol/*analogs & derivatives/pharmacology ; Membrane Potential, Mitochondrial/*drug effects ; Mice ; Mice, Inbred BALB C ; Reactive Oxygen Species/*metabolism ; Signal Transduction/*drug effects