The interaction of 5-fluorouracil (5-FU) with deoxyribonucleic acid (DNA) and serum albumin and the influence of some metal ions on the interaction have been studied by using spectral methods of UV-absorption,fluorescence and circular dichroism. It was shown that the interaction of 5-FU with DNA and serum albumin was effected by some metal ions. The binding costant of 5-FU with serum albumin was found to be KHSA = 4.38 × 103(mol/L)-1 and KBSA =4.95 × 103(mol/L)-1 and the distance between the bound 5-FU and the tryptophan residue was also determined to be rHSA = 3.53 nm, rBSA = 3.51 nm.

In this paper,a unique case of organ transplantation was inspected by organ transplant ethics committee,through which we try to investigate the mode of current operation,problems and confusion of organ transplant ethics committee in China by the constitutive principles,inspection scope,process,content,especially the functional authority and other relevant contents of hospital ethics committee.

This paper describes the role,method and experience,and working model of medical ethics in large-scale hospitals,and holds that the modern hospital management mode has transformed from scientific management to humanism-based management,whose essence is the transformation of managing concept,and the embody of management ethics and management culture.Important connotations and primary task including employing virtue in hospital management,obeying legal regulations in medical practice,and conducting humanistic medicine should be emphasized and concerned in hospital management.

Objective To investigate the antimicrobial resistance mechanisms and genetic homogeny of Salmonella from community acquired infections in Shenzhen,China.Methods Ninety-three of Salmonella were isolated from 2002 to 2007 at Shenzhen People's Hospital,China.PCR and DNA sequencing were used to investigate the mutation in QRDR of the gyrA,gyrB,parC and parE.Plasmid mediated quinolone resistance genes including qnr and aac(6')-Ib-cr,β-lactamase genes including blaTEM,blaSHV,blaOXA, blaCTX-M, and class 1 integron were detected. All isolates were typed by PFGE. Results S. enterica typhi and S. enterica paratyphi A were susceptible to ampicillin, chloramphenicol, trimethoprim/sulfamethoxazole, ceftriaxone and ciprofloxacin, with the susceptible rate of 96%-100%. Fifty-two percent (13/25) of S. enterica typhi and 95% (61/64) of S. enterica paratyphi A were resistant to nalidixic acid. Twenty-four percent (6/25) of nalidixic acid-resistant S. enterica typhi and 94% (60/64) of nalidixic acid-resistant S. enterica paratyphi A showed decreased susceptibility to ciprofloxacin (MIC of 0. 125-1 μg/ml).All nalidixic acid-resistant (susceptible to ciprofloxacin ) Salmonella (NARS) isolates had a single substitution in the QRDR of GyrA, and 91% (68/75) of these isolates carried the substitution Ser83Phe in GyrA. Two mutations in the QRDR of GyrA were detected in both of two ciprnfloxacin-resistant Salmonella,with the additional one mutation in the QRDR of parC. Plasmid mediated quinolone resistance genes including qnr and aac(6')-lb-cr were not detected in any isolate. The blaCTX-M-14 gene was detected in a ceftriaxoneresistant isolate of S. enterica paratyphi A, with ISEcpl located on the upstream of it. Three muhidrugresistant strains of Salmonella all carried one 1 900 bp classⅠ integron gene cassette dhfrⅫ-orfF-aadA2,with the additional one β-lactamase gene of blaTEM-1, or blaOXA-30. Twenty-two distinct PFGE patterns were observed among twenty-five S. enterica typhi. The PFGE patterns of sixty-four S. enterica paratyphi A showed limited genetic diversity (average similarity of 91% ). Ninety investigated inpatients were infected in the community. Six patients infected by S. enterica paratyphi A had a travel history before infection. Conclusions Nalidixic acid-resistant S. enterica typhi and S. enterica paratyphi A are highly prevalent in Shenzhen,China. The mutation in the QRDR of GyrA is the prevalent mechanism responsible for the resistance to nalidixic acid in Slmonella. The great genetic similarity among S. enterica paratyphi A isolates indicates endemic disease from the presence of a single clone over 6-year period.

In order to express the gene of LEN-5 β-lactamase from a Klebsiella pneumoniae strain,plasmids in the strain were extracted and an 879bp product of LEN-5 gene was obtained with PCR.After being digested with Nde I and Xho I,LEN-5 gene was cloned into pET-26b (+) vector.Then it was confirmed by digestion and DNA sequencing in recombinant plasmid before transformed into E.coli BL21 (DE3).After inducing by IPTG,LEN-5 β-lactamase was expressed.Protein extraction was processed by ultrasonic and protein activity was detected by nitrocefin.The isoelectric focusing electrophoresis showed a pI of 7.6.These results indicated that the LEN-5 gene has been cloned and expressed in prokaryote cell successfully.

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 study the epidemiological features of Cryptococcus neoformans and Cryptococcus gattii isolated from clinical samples in Shenzhen and to elucidate the distribution of species,varieties,genotypes and mating types within the strains tested.Methods The strains involved in this study were 55 cryptococcal strains isolated from our clinical samples.The canavanine-glycine bromthymolblue (CGB) culture was performed to distinguish Cryptococcus neoformans from Cryptococcus gattii.The genotype was characterized by polymerase chain reaction (PCR) fingerprinting with primer M13.The Cryptococcus gattii species and varieties of grubii and neoformans together with two opposite mating type α and a were identified by PCR with variety-specific and mating type-specific primers.The GEF1-restriction fragment length polymorphism analysis was conducted to simultaneously determine the genotype and mating types of strains tested.The sequence type of IGS1 region was analyzed for the VG Ⅱ genotype.Results Of the 55 tested cryptococcal strains,52 were Cryptococcus neoformans,all of which were var.grubii,genotype VN Ⅰ and mating type α.The remaining 3 strains were Cryptococcus gattii,among which,one was genotype VG Ⅰ and mating type α,and two were genotype VG Ⅱ and mating type α.The two VGⅡ genotype strains belonged to the sequence type Ⅱ.Conclusions The strains belonging to the Cryptococcus neoformans var.grubii,genotype VN Ⅰ and mating type α predominate in causative pathogens of cryptococcosis in Shenzhen.Cryptococcus gattii accounts for minority of the cryptococcal isolates,and the highly pathogenic VG Ⅱ genotypes in foreign countries are also characterized.The sequence types of IGS1 region of the two VG Ⅱ strains are in accord with VG Ⅱb sub-genotype.

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

Objective To evaluate the capability of multilocus variable-number tandem-repeat ( VNTR) analysis ( MLVA) and pulsed-field gel electrophoresis ( PFGE) for genotyping Salmonella enterica serovar Typhi (S.Typhi) isolates.Methods Five polymorphic VNTRs (SAL02,SAL11,SAL16,SAL20, and TR4699 ) that were observed in S.Typhi strains from previous studies were selected to establish MLVA . Twenty-one epidemiologically unrelated S.Typhi strains that were isolated from Shenzhen ,China from 2002 to 2007 were genotyped by the established MLVA , and the results were compared with those by PFGE . Results The Simpson′s index of diversity ( D value ) for all five different VNTRs ranged from 0.838 to 0.943 .A total of 19 MLVA profiles and 19 PFGE profiles were found , respectively .The D value for both MLVA and PFGE were 0.99 and the test results from two analyses were identical .Conclusion The five polymorphic VNTRs analysis could be used as an alternative typing scheme for epidemiologic investigation of S.Typhi infection .