OBJECTIVE To find out the clinical characteristics of nosocomial infections with Stenotrophomonas maltophilia(SMA) and investigate the disinfectant resistant gene of qacE△1,improve the diagnosis and decrease of nosocomial infection cases.METHODS Toally 165 strains of SMA were clinically isolated from 2004 to 2007.The gene of qacE△1 was analyzed by polymerase chain reation(PCR) and homology of the strains was analyzed by the method of by pulsed field gel electrophoresis(PFGE) genotype.RESULTS Susceptible factors were old age,seriousness of underlying disease,prolonged hospitalization and invasive operation with infection of SMA.The lower respiratory tract infection was mostly common with SMA,rate of which was 87.9%.Antibiotic sensitive rate more than 80% against SMA was minocycline,trimethoprim-sulfamethoxazole and levofloxacin.The positive rate of gene qacE△1 was 13.3% in 60 strains tested.Two genotypes in SMA strains from respiratory ICU(RICU) were with the same clone.This result proved that clone transmission occurred in RICU.CONCLUSIONS SMA is an important nosocomial infection pathogen.With the multi-drug resistance,the therapy of infection with SMA is very hard in clinic.As result of gene of qacE△1 and the same clone transmission,clinicians should play an important role of surveillance of effect of disinfection.

Objective To evaluate the utility of carbapenem inactivation method (CIM) in detecting carbapenemase-producing Acinetobacter baumannii.Methods A total of 121 strains of A. baumannii were identified and subjected to antimicrobial susceptibility testing by VITEK compact. Carbapenem inactivation method (CIM) was applied to detect the carbapenemase in the A. baumannii strains. The OXA-23 type carbapenemase-encoding genes were analyzed by common PCR method.Results Six-eight of the 121 strains showed resistance to imipenem and meropenem. PCR showed that 65 of the 68 strains carried OXA-23 gene. CIM was positive in 66 of the 68 strains. And 52 of the 121A. baumannii strains were susceptible to imipenem and meropenem. PCR showed that OXA-23 gene was negative in 49 of the 52 strains. CIM was negative in the 52 strains of non-carbapenemase-producing A. baumannii. Only one strain was resistant to imipenem but susceptible to meropenem. CIM was negative but QXA-23 was positive for this strain. The sensitivity and the specificity of CIM was 94.2% and 98.1% respectively in detecting carbapenemase-producing A. baumannii.Conclusions The results of CIM were consistent with the results obtained by PCR to detect the encoding gene of OXA-23. CIM is inexpensive, easier to operate and interpret than PCR method. CIM is applicable to detect OXA-23 type carbapenemase rapidly inA. baumannii.

OBJECTIVE:To optimize the extraction technology of total lignans from pine needles of Cedrus deodara. METH-ODS:Using ethanol volume fraction,ratio of liquid to solid and extraction time as response factor,the content of total lignans as response value,the response surface methodology test was conducted based on Box-Behnken design to optimize the extraction tech-nology of total lignans from pine needles of C. deodara. RESULTS:The optimal extraction technology was as follows as ethanol volume fraction of 78%,ratio of liquid to solid 25∶1,extraction time 1.75 h. The content of total lignans from pine needles of C. deodara was 99.2 mg/g,which was close to predicted value 100.49 mg/g,with relative deviation of 0.65%. CONCLUSIONS:Op-timized extraction technology of pine needles of C. deodara by response surface methodology is feasible and stable,and has good predictability.

Objective To identify the genotype of clinical stenotrophomonas maltophilia(SMA) isolates and investigate the characteristics of SMA in nosocomial infections.Methods Totally 165 strains of SMA were clinically isolated during the period of 2004 to 2007.Disc diffusion test(K-B method) was used for antibiotic susceptibility.qacE△1 gene was detected by polymerase chain reation(PCR).The gene homology in the SMA strains was analyzed by pulsed field gel electrophoresis(PFGE).Results Among the tested SMA strains 87.9% sourced from low respiratory tract infection.The antibiotics with more than 80% of sensitive rate against SMA were minocycline,trimethoprim-sulfamethoxazole and levofloxacin.The positive rate of qacE△1 gene was 13.3% in 60 tested strains.The analysis of gene homology for the 11 clinical strains showed that two genotypes from identical clone were found in both respiratory ICU and emergency ICU respectively.Conclusions SMA was an important pathogenic bacterium in nosocomial infections.The treatment for SMA infection is very difficult since its multi-drug resistance.More attention for effective sterilization and isolation of patients must be paid to prevent the transmission of SMA from same clone.

Objective To evaluate the in- vitro antibacterial activity of e thanol- extract of Galla Chinensis against Staphycoccus aureus (S. aureus).Meth ods The minimum inhibitory concentration (MIC50) of ethanol- extract of Galla Chinensis against 112 strains of S. aureus was detected by using agar dilution method.Results The MIC50 and MIC90 of ethanol- extract of Galla Chinensis aga inst 84 strains of MRSA (methicillin- resistant staphylococcus aureus) were 0. 315, 0.315 mg/mL, and those against 28 strains MSSA (methicillin- sensitive sta phylococcus aureus) were 0.63 and 0.315 mg/mL respectively.Conclusion Ethanol - extract of Galla Chinensis has a strong antibacterial activity against S.aure us.

Objective To explore the role of intracellular reactive oxygen species (ROS) in the senescence of bone marrow mesenchymal stem cells(BMSCs)in patients with systemic lupus erythematosus(SLE) and the underlying mechanisms that controls the intracellular ROS levels in vitro. Methods Human bone marrow aspirates were collected from iliac of eight donors and eight SLE patients and cultured in vitro.Morphological appearance of BMSCs at different passages was examined by inverted microscope. Nuclear size was measured by fluorescence microscope. BMSCs were monitored using the senescence associated β-galacto-sidase (SAβ-gal) assay to characterize senescence in vitro. The quantification of intracellular ROS production was detected by flow cytometry. Real-time PCR technique was used to determine the gene expressions of PI3K, KRas, NRas and FoxO3 at transcription level. The expression of FoxO3, phospho-FoxO3 (p-FoxO3),AKT and phospho-AKT (p-AKT) protein were determined by Western blot analysis. Statistical analysis was conducted with t-test and Mann-Whitney rank test.Results There were no differences in morphology and nuclear size[(31.4±4.5) vs (28.2±4.8) μm, P=0.628] of BMSCs between SLE patients and normal controls.The percentage of SA β-gal positive BMSCs from SLE patients was higher than that from healthy controls [(31.8±9.0)% vs (12.4±0.7)%, P＜0.05]. Intracellular ROS levels of BMSCs from SLE patients increased more significantly than healthy donors in vitro (34600±9600 vs 17 958±5400, P＜0.05). No significant differences in the expression of PI3K, NRas, KRas and FoxO3 from SLE subjects were observed at mRNA levels compared with normal controls, though all showed a similar upward trend. The expression of p-FoxO3 and p-AKT of BMSCs from SLE patients increased significantly compared with healthy controls at protein levels.Conclusion These data suggest that BMSCs from SLE patients aged more quickly, with high SA β-gal activity and up-regulation of intracellular ROS, which is associated with up-regulation of p-FoxO3 and pAKT at protein levels. These results indicate that bone marrow mesenchymal cell senescence may be associated with the pathogcnesis of SLE by maintaining the lifespan of BMSCs.

Objective To investigate the pathogen culturing of the catheter related infection(CRI),cathe-ter related bloodstram infection(CRB)and risk factors after central venous catheter(CVC)of cardiovascular surgery in order to provide the beneficial reference.Methods From Jan 2005 to Dec 2005,a total of 300 cases central ve-nous cathers were determined,and the cusp of the catheters was determined by bacteria cultivation,and blood bacte-ria cultivation.Results The infection happened in 35 of 300 patients with inserted central venous catheter.The cusps of CRI rate was 11.7%.CRB rate was 1.7%.54.3%pathogens were gram-positive cocci,34.3% were gram-negative bacilli,11.4% were fungi.The most common strain were Staphylococcus epidermis,Staphylococcus aureus,Klebsiella pneumoniae,Pseudomonas aeruginose,and Candiadia albicans.The infection rate increased obviously when the dwelling time>6 d.Conclusion CRI and CRB are the most severe complication of CVC,and it is important to cut down the death with the early diagnosis and applying antibiotics rationally.

Objective To investigate the expression of FcγRⅡb on peripheral B cells and its clinical significance in primary Sj(o)gren's syndrome (pSS).Methods FcγRⅡb expression on peripheral B cells from 19 pSS patients and 15 healthy controls was examined by flow cytometry.The levels of serum anti-SSA and SSB antibodies were determined using enzyme-linked immunosorbent assay (ELISA).Data were analyzed with t test,one-way ANOVA,SNK-q test and Pearson's correlation test.Results The percentage of memory CD19+CD27+ B cell subpopulation was significantly lower in pSS patients [ (20.8±2.7)％] when compared to normal controls [(37.8±2.2)％ ](t=-4.002,P＜0.01).The level of expression of FcγRⅡb in active pSS memory CD19+CD27+ B cells [ MFI(74±8)] was significantly reduced when compared to inactive [ MFI( 132±11)] and normal controls [ MFI (139±12)] (F=10.699,P＜0.01).The level of expression of FcγRⅡb on memory CD19+CD27+ B cells from pSS patients was inversely correlated with Sj(o)gren's syndrome disease activity index (SSDAI) (r=-0.744,P=0.0003 ).pSS patients with the serum anti-SSA/SSB antibodies positive group [ MFI(75+3),(48±7)] displayed a lower expression of FcγRⅡb on memory CD19+CD27+ B cell than in patients with the serum anti-SSA/SSB antibodies negative group [MFI( 122±11),(108±9)] (t=-4.336 and -3.776 respectively,the P value of both tests were less than 0.01).The level of expression of FcγRⅡb in the memory CD19+CD27+ B cells of patients with active pSS was inversely correlated with anti-SSA antibody titers (r=-0.685,P=0.014).Conclusion The expression of FcγRⅡb on peripheral memory B cells from active pSS patients is inversely correlated with SSDAI and is also inversely associated with anti-SSA antibody levels.Decreased expression of FcγRⅡb might play an important role in the pathogenesis of pSS.

Objective To investigate the apoptosis of bone marrow mesenchymal stem cells(BMSCs)from systemic lupus erythematosus(SLE)patients and the expression of apoptotic molecules.Methods BMSCs were isolated from bone marrow of SLE patients and normal controls by density eentrifugation and adhesive culture in vitro.The apoptosis of BMSCs were evaluated by TUNEL assay.The expressions of Fas.Bcl-2 and the activity of Caspase 8 were detected by flow cytometry.Real-time PCR technique was used to determine the gene expressions of Fas,Bcl-2,Bax,Bcl-w,Caspase 8 and Apaf-1.Meanwhile,cytochrome C was detected by immunocytochemistry.Statistical analysis was conducted with t-test and Mann-Whitney rank test.Results The percentage of apoptotic BMSCs increased in SLE patients compared with healthy donors[(64±10)%vs [14±9)%,U=0,P<0.05 ].The expression of Bcl-2 in BMSCs of SLE patients was lower than the normal controls at protein leve[(11±9)%vs(56±18)%,U=0,P<0.05 ],and mRNA level(0.2±0.2vs 2.4±0.7,U=24,P<0.05).More cytochrome C positive pellets in the cytosolic fraction could be detected in BMSCs from SLE patients compared with healthy controls [(56±21)%vs (16±16)%,U=1,P<0.05].The activity of Caspase 8 was enhanced[(49±14)%vs(16±12)%,U=0.P<0.05 ],although with no significant difierence at mRNA Ievel.Both groups expressed Fas but with no significant difference (U=19,P>0.05).Conclusion BMSCs from SLE patients undergo more apoptosis,the mechanisms may be associated with the down regulation of Bcl-2,up-regulation of Cytoehrome C in cytoplasm and the activation of Caspase 8,which directs the intrinsic and extrinsic apoptosis pathways.

OBJECTIVE:To study the vitro antibacterial activity of domestic teicoplanin against224strains of enterococ-ci.METHODS:Determination of MIC of domestic teicoplanin against169strains of entercococcus faecalis and51strains of E.faecium was tested by agar dilution method,and its antibiotic effect was compared with that of the imported teicoplanin and other antibiotics.RESULTS:The MIC 50 of domestic teicoplanin against169strains of E.faecalis and51strains of E.faecium were0.125,0.25?g/ml respectively,MIC 90 were2,1?g/ml respectively;The MIC 50 of imported teicoplanin against E.faecalis and E.faecium were0.25,0.25?g/ml respectively,MIC 90 were1,0.5?g/ml respectively.CONCLUSION:Two kinds of te-icoplanin have strong antibacterial activity against224strains of enterococci;the sensitivity of224strains of enterococci to both kinds was100%.