OBJECTIVETo study the differences of theantimicrobial-resistant profiles between the isolates of Staphylococci aureu from children and from adults.

METHODSStaphylococci was identified by the plasma coagulase test, Staphylococci monoclonal antibody and VITEK-32 fully automated microbiology analyzer.Antimicrobial susceptibility testing was done by the K-B disk diffusion for 84 Staphylococci isolates from children and 74 Staphylococci isolates from adults. Cefoxitin was used for detecting methillicin-resistant Staphylococcus aureus (MRSA) by the disk diffusion test.

RESULTSSeven (8%) MRSA isolates were found in Staphylococci isolates from children compared with 35 MRSA isolates (47%) in those from adults (p<0.01). All strains were susceptible to vancomycin. All strains from children were susceptible to fusidic acid. The resistant rates of the isolates from children to cefazolin, cefuroxime, gentamicin, cefoxitin, and levofloxacin were significantly lower than those from adults (p<0.01).

CONCLUSIONSThe antimicrobial resistance of the Staphylococcus aureus isolates from adults is more prevalent than that in the isolates from children.

Adult ; Child ; Drug Resistance, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; isolation & purification ; Microbial Sensitivity Tests ; Staphylococcus aureus ; drug effects

OBJECTIVETo analyze the change in drug resistance of Staphylococcus aureus (SAU) in the PLA general hospital from January 2008 to December 2012, and to provide solid evidence to support the rational use of antibiotics for clinical applications.

METHODSThe SAU strains isolated from clinical samples in the hospital were collected and subjected to the Kirby-Bauer disk diffusion test. The results were assessed based on the 2002 American National Committee for Clinical Laboratory Standards (NCCLS) guidelines.

RESULTSSAU strains were mainly isolated from sputum, urine, blood and wound excreta and distributed in penology, neurology wards, orthopedics and surgery ICU wards. Except for glycopeptide drugs, methicillin-resistant Staphylococcus aureus (MRSA) had a higher drug resistance rate than those of the other drugs and had significantly more resistance than methicillin-sensitive Staphylococcus aureus (MSSA) (P < 0.05). In the dynamic observation of drug resistance, we discovered a gradual increase in drug resistance to fourteen test drugs during the last five years.

CONCLUSIONDrug resistance rate of SAU stayed at a higher level over the last five years; moreover, the detection ratio of MRSA keeps rising year by year. It is crucial for physicians to use antibiotics rationally and monitor the change in drug resistance in a dynamic way.

Anti-Bacterial Agents ; pharmacology ; Drug Resistance, Multiple, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Staphylococcal Infections ; drug therapy ; Staphylococcus aureus ; drug effects

AIMTo investigate the mechanism of the interaction between montmorillonite and bacteria by studying the reactions of different charges of montmorillonites with bacteria.

METHODSBacteriostatic test: one loop of E. coli and Staphylococcus aureus at the concentration of 1 x 10(6).mL-1 was incubated to the plate culture medium containing different concentrations of montmorillonite, and incubated 24 h to observe the growth of bacteria. Bacterial adsorptive test: different amounts of montmorillonite were added into the artificially simulated intestinal solution (containing bacteria 1 x 10(7).mL-1). After the culture, the bacterial colonies were counted.

RESULTSThe results showed that montmorillonite per se showed no bacteriostatic or bactericidal effect, but after exchange with metal ion and functional groups which inhibits bacteria, then it showed these activities. Adsorption was the main way between montmorillonite and bacteria. The special way of fixing bacteria into the "carriage" of montmorillonite gel which carry this structure was its pharmacological basis of curing diarrhea. The adsorption effect was related to layer charge density of the montmorillonites.

CONCLUSIONMontmorillonite showed adsorption ability of bacteria with minus related to its layer charge, but has no bacteriostatic and bactericidal effect.

Adsorption ; Anti-Ulcer Agents ; pharmacology ; Bentonite ; pharmacology ; Escherichia coli ; drug effects ; Staphylococcus aureus ; drug effects

OBJECTIVETo prepare and evaluate novel chlorine dioxide-based disinfectant powder in single-pack that is more convenient for use and transportation.

METHODSOrthogonal experiment was performed to determine the recipe of the disinfectant powder. Stability test, suspension quantitative bactericidal test, simulation field trial, and animal toxicity test were carried out to observe its bactericidal and toxicological effects.

RESULTSThe orthogonal experiment showed that the type of water solution had no effect on the disinfectant powder and the best ratio of sodium chlorite to solid acid was 1:3. Ten grams of the disinfectant powder was fully dissolved in 20 mL water for 2 min, and diluted to 500 mL in water. After 5-10 min, the concentration of chlorine dioxide (ClO2) solution was 266 mg/L to 276 mg/L. After stored at 54 degrees C for 14 d, the average concentration of ClO2 was decreased by 5.03%. Suspension quantitative bactericidal test showed that the average killing logarithm (KL) value for both Staphylococcus aureus and Escherichia coli in 100 mg/L ClO2 solution for 2 min was over 5.00. in simulation field trial, the average descending KL value for Escherichia coli in the solution containing 100 mg/L ClO2 for 5 min was over 3.00. The mouse acute LD50 in the solution 5 times exceeded 5000 mg/kg. The disinfectant powder was not toxic and irritative to rabbit skin and had no mutagenic effect on mouse marrow polychromatic erythrocytes (PCE).

CONCLUSIONThe stability and bactericidal efficacy of solid chlorine dioxide-based disinfectant powder in single-pack are good. The solution containing 100 mg/L ClO2 can kill vegetative forms of bacteria. The concentration of ClO2 on the disinfecting surface of objects is 100 mg/L. The disinfectant powder is not toxic and irritative.

Chlorine Compounds ; pharmacology ; Disinfectants ; pharmacology ; Escherichia coli ; drug effects ; Oxides ; pharmacology ; Staphylococcus aureus ; drug effects

OBJECTIVETo study the distribution and drug resistance of methicillin resistant Staphylococcus strains in various specimens of inpatients in burn wards, and to provide reference for clinical treatment.

METHODSBacteria were isolated from specimens of wound exudate, blood, sputum, and bronchoalveolar lavage fluid etc., which were collected from patients hospitalized in our burn wards from January 2008 to December 2010. The bacteria were routinely cultured and identified. Drug resistance of the Staphylococci to 15 antibiotics commonly used in clinic was identified by K-B disk diffusion method. Data were processed with statistical software WHONET 5.5. The homology of 40 strains of methicillin resistant Staphylococcus aureus (MRSA) was analyzed by pulsed-field gel electrophoresis (PFGE).

RESULTSAltogether 386 strains of Staphylococcus were isolated, including 196 strains of Staphylococcus aureus and 190 strains of coagulase negative Staphylococcus. The mean annual isolation rates of MRSA and methicillin resistant coagulase negative Staphylococcus (MRCoNS) were respectively 73.00% (143/196) and 74.20% (141/190). The resistance rates of MRSA and MRCoNS to β-lactams drugs, such as penicillin, oxacillin, cefazolin, and cefuroxime were 100.00% in every year. No Staphylococcus strains resistant to vancomycin, teicoplanin, or linezolid were found. Three different PFGE patterns A, B, and C were identified among 40 MRSA strains, including 33 strains of type A (30 strains in sub-type A1 and 3 strains in sub-type A2), 6 strains of type B (respectively 3 strains in sub-types B1 and B2), and 1 strain of type C.

CONCLUSIONSThe isolation rates of MRSA and MRCoNS were high in our burn wards from January 2008 to December 2010. All of them showed strong drug resistance property, and they were multidrug resistant. The most prevalent strain was PFGE type A.

Burns ; microbiology ; Drug Resistance, Multiple, Bacterial ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects

INTRODUCTIONCeftaroline is a fifth-generation cephalosporin with activity against methicillin-resistant Staphylococcus aureus (MRSA) that was recently launched in Singapore. It received approval from the United States (US) Food Drug Administration (FDA) and European Commission for the treatment of adult patients with community-acquired pneumonia (CAP) and complicated skin and soft tissue infections (cSSTI). This study aimed to review current published data and determine its clinical role, particularly in the local setting.

MATERIALS AND METHODSA literature review on published articles in English on ceftaroline, focusing in particular on clinical trials and other clinical reports. Susceptibility testing was also performed on a limited sample of local MRSA and Streptococcus pneumoniae isolates.

RESULTSCeftaroline has an extensive spectrum of activity, including coverage of MRSA and multidrug-resistant S. pneumoniae. However, it has limited activity against non-fermenting Gram-negative bacteria and is susceptible to hydrolysis by extended spectrum beta-lactamases. It is only available for intravenous delivery, with a reconstituted stability of just 6 hours, rendering it unavailable for use for outpatient antibiotic therapy. Clinical trials demonstrate non-inferiority compared to first-line comparators in the treatment of CAP and cSSTI. Published case reports/series suggest a potential greater role in the treatment of MRSA bacteremia and endocarditis. No resistance was found among local archived MRSA and S. pneumoniae isolates.

CONCLUSIONWe believe ceftaroline will occupy primarily niche roles for culture-directed treatment of various infections--in particular those caused by MRSA--until further clinical trial data become available. A variety of factors render it less useful or appealing for empirical treatment of CAP or healthcare-associated infections.

Cephalosporins ; pharmacology ; therapeutic use ; Humans ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Singapore ; Staphylococcal Infections ; drug therapy

Evolution, Molecular ; Methicillin Resistance ; Staphylococcus aureus ; classification ; drug effects ; genetics ; isolation & purification

OBJECTIVETo study the effect of DNase I on biofilm formation of Staphylococcus aureus.

METHODSThe growth curve of S. aureus was detected using a spectrophotometer. The adhesion of S. aureus was analyzed using flat colony counting method, and the biofilm formation was assayed using the 96-well crystal violet staining method.

RESULTSExposure to different concentrations of DNase I did not obviously affect the growth of S. aureus but significantly inhibit the formation of bacterial biofilms in a dose-dependent manner. DNase I inhibited the adhesion of S. aureus at different growth stages. When combined with antibiotics, DNase I resulted in a signi?cant decrease in the established bio?lm biomass compared to antibiotics or DNase I used alone.

CONCLUSIONDNase I can effectively inhibit biofilm formation of S. aureus and enhance the inhibitory effect of antibiotics against S. aureus biofilms.

Anti-Bacterial Agents ; Biofilms ; drug effects ; Deoxyribonuclease I ; chemistry ; Staphylococcus aureus ; growth & development

Child ; Cross Infection ; microbiology ; Disease Outbreaks ; Humans ; Methicillin-Resistant Staphylococcus aureus ; classification ; drug effects ; genetics

BACKGROUNDThe infection rate of methicillin-resistant Staphylococcus aureus (MRSA) is increasing yearly due to the overprescription of antibiotics. Traditional Chinese compound medicines are less inclined to induce bacterial resistance in the clinical setting because of their multi-acting mechanisms. However, most current research is limited to bacteriostasis in vitro using single extracts or formulations. Plasma pharmacology is an in vitro method, using what is called "medicine serum". The aim of this study was to investigate whether the medicine serum of compound Qingre granules (QRKL) alone or in combination with antibiotics may treat MRSA infection in the clinic.

METHODSAn animal model of MRSA resistance was created by injecting rabbits with the standard strain of MRSA ATCC43300. Infected rabbits were treated with QRKL by intragastric administration. Sixty minutes after the last intragastric administration, serum was obtained from the rabbits by heart puncture to obtain what is termed "medicine serum". The minimum inhibitory concentration (MIC) of QRKL, medicine serum alone, or serum combined with antibiotics was assessed by agar dilution.

RESULTSwere compared with the growth of sixteen isolates of MRSA.

RESULTSThe MIC of QRKL to the standard strain ATCC43300 was 10.00 mg/ml. The MIC(90) of vancomycin was 1.00 microg/ml, which, when combined with QRKL, dropped to 0.50 microg/ml. The MIC(90) of cefuroxime alone was 512.00 microg/ml. This level also decreased to 256.00 microg/ml when combined with QRKL. The addition of QRKL thus significantly reduced the MIC of both cefuroxime and vancomycin compared with antibiotics alone (P < 0.01). The MIC(90) of vancomycin with medicine serum decreased to 0.50 microg/ml, and the MIC of vancomycin with medicine serum also descended compared with using vancomycin alone (P < 0.01).

CONCLUSIONSThe growth of MRSA can be inhibited by QRKL or medicine serum of QRKL in vitro. The addition of QRKL results in increased sensitivity of MRSA to vancomycin and this may provide a novel treatment for patients with MRSA infection.

Drugs, Chinese Herbal ; pharmacology ; Methicillin-Resistant Staphylococcus aureus ; drug effects ; Microbial Sensitivity Tests ; Vancomycin ; pharmacology