OBJECTIVE: To investigate whether the in vitro sensitivity of cefazolin sodium to the bacteria was altered after nanoparticlization. METHODS: The minimal inhibitory concentrations (MIC) of cefazolin sodium before and after nanoparticlization to S. aureaus and E. coli. were determined by microdilution. RESULTS: The MIC of nanoparticlized cefazolin sodium to S. aureaus and E. coli. had no significant change compared with that of non-nanoparticlized one. CONCLUSION Nanoparticlization will not decrease the sensitivity of cefazolin sodium to the bacteria.
Anti-Bacterial Agents ; pharmacology ; Cefazolin ; pharmacology ; Escherichia coli ; drug effects ; Microbial Sensitivity Tests ; Nanostructures ; Staphylococcus aureus ; drug effects

Xiyanping is used to treat infectious diseases with antibiotics in clinic. The aim of this study is to investigate the mechanism of Xiyanping through studying the effect of the combination of Xiyanping with Cefazolin on the chemotaxis and phagocytic function of peripheral blood neutrophils in mice. Ten healthy mice were in control group. Forty healthy mice in experimental group were infected with staphylococcus aureus, and were randomly divided further into four groups, i. e. model group, Xiyanping group, Cefazolin group and combination group (Xiyanping with Cefazolin). Mice in the control group and model group were given normal saline (NS) through abdomen while those in other groups were given Xiyanping, Cefazolin, and Xiyanping with Cefazolin, respectively. The chemotaxis of peripheral blood neutrophils was detected with the transwell method, and the phagocytic function of peripheral blood neutrophils was analyzed with flow cytometry (FCM). In the present study, there was no significance on the chemotactic index of peripheral blood neutrophils in all the groups (P > 0.05). The actual phagocytotic rate and index of peripheral blood neutrophils in the blank group, Xiyanping group, and the combination group were significantly higher than those of the model group and Cefazolin group (P < 0.05). However, those were not significant in the blank group, Xiyanping group, and the combination group (P > 0.05) or between the model group and Cefazolin group (P> 0.05). Our results suggested the combination of Xiyanping and Cefazolin could enhance the therapeutic effect by improving the phagocytic function of peripheral blood neutrophils.
Animals ; Anti-Bacterial Agents ; pharmacology ; Cefazolin ; pharmacology ; Chemotaxis ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Mice ; Neutrophils ; cytology ; drug effects ; Phagocytosis ; Staphylococcal Infections ; immunology ; Staphylococcus aureus

OBJECTIVE: Aeromonas has recently been recognized as an emerging human pathogen. Aeromonas-associated diarrhea is a phenomenon occurring worldwide. This study was designed to determine the prevalence, genetic diversity, antibiotic resistance, and pathogenicity of Aeromonas strains isolated from food products in Shanghai. METHODS: Aeromonas isolates ( n = 79) collected from food samples were analyzed using concatenated gyrB- cpn60 sequencing. The antibiotic resistance of these isolates was determined using antimicrobial susceptibility testing. Pathogenicity was assessed using β-hemolytic, extracellular protease, virulence gene detection, C. elegans liquid toxicity (LT), and cytotoxicity assays. RESULTS: Eight different species were identified among the 79 isolates. The most prevalent Aeromonas species were A. veronii [62 (78.5%)], A. caviae [6 (7.6%)], A. dhakensis [3 (3.8%)], and A. salmonicida [3 (3.8%)]. The Aeromonas isolates were divided into 73 sequence types (STs), of which 65 were novel. The isolates were hemolytic (45.6%) and protease-positive (81.0%). The most prevalent virulence genes were act (73.4%), fla (69.6%), aexT (36.7%), and ascV (30.4%). The results of C. elegans LT and cytotoxicity assays revealed that A. dhakensis and A. hydrophila were more virulent than A. veronii, A. caviae, and A. bivalvium. Antibiotic resistance genes [ tetE, blaTEM, tetA, qnrS, aac(6)-Ib, mcr -1, and mcr-3] were detected in the isolates. The multidrug-resistance rate of the Aeromonas isolates was 11.4%, and 93.7% of the Aeromonas isolates were resistant to cefazolin. CONCLUSION The taxonomy, antibiotic resistance, and pathogenicity of different Aeromonas species varied. The Aeromonas isolates A. dhakensis and A. hydrophila were highly pathogenic, indicating that food-derived Aeromonas isolates are potential risks for public health and food safety. The monitoring of food quality and safety will result in better prevention and treatment strategies to control diarrhea illnesses in China.
Aeromonas/genetics* ; Animals ; Anti-Bacterial Agents/pharmacology* ; Caenorhabditis elegans ; Cefazolin ; China/epidemiology* ; Diarrhea ; Drug Resistance, Multiple, Bacterial/genetics* ; Genetic Variation ; Humans ; Peptide Hydrolases/genetics* ; Virulence/genetics*

OBJECTIVETo explore the possibility of repairing long segmental bone defects and preventing infection with cefazolin loaded bone matrix gelatin (C-BMG).

METHODSC-BMG was made from putting cefazolin into BMG by vacuum absorption and lyophilization techniques. The sustaining period of effective drug concentration in vitro and in vivo was detected. The time of inhibiting bacteria, and the drug concentration in local tissues (bone and muscle) and plasma after implantation of C-BMG were examined by high performance liquid chromatography.

RESULTSThe effective inhibition time to staphylococcus aureus of C-BMG was 22 days in vitro; while 14 days in vivo. The cefazolin concentration in local tissues was higher in early stage, and later it kept a stable and low drug release. C-BMG showed an excellent ability to repair segmental long bone defects.

CONCLUSIONSC-BMG can gradually release cefazolin with effective drug concentration and has excellent ability to repair segmental bone defects. It can be used to repair segmental long bone defects and prevent infection after operation.

Animals ; Bone Matrix ; Bone Substitutes ; therapeutic use ; Cefazolin ; pharmacology ; Cephalosporins ; pharmacology ; Escherichia coli ; drug effects ; Gelatin ; Microbial Sensitivity Tests ; Osteogenesis ; Prostheses and Implants ; Rabbits ; Radius Fractures ; surgery ; Staphylococcus aureus ; drug effects ; Surgical Wound Infection ; prevention & control

We investigated the risk factors for resistance to ciprofloxacin, cefazolin, ampicillin and co-trimoxazole in Escherichia coli isolates from urine of Korean female patients with acute uncomplicated cystitis (AUC). A total of 225 patients and their E. coli isolates were prospectively and nationwidely enrolled between May and October, 2006. All the antimicrobials did not show any differences according to the age group. A higher rate of ciprofloxacin resistance was observed in the south (OR: 3.04, 95% CI: 1.19-7.80 for Chungcheong-do & Jeolla-do; OR: 3.04, 95% CI: 1.22-7.58 for Gyeongsang-do) compared to Gyeonggi-do. Two recurrences of AUC in the past year was an important risk factor for antimicrobial resistance (ciprofloxacin; OR: 6.71, 95% CI: 1.86-24.11 and cefazolin; OR: 5.72, 95% CI: 1.20-27.25). However, the resistance to co-trimoxazole and ampicillin was not associated with any of the risk factors. This study also revealed the pattern of multi-drugs resistance in ciprofloxacin resistant E. coli strains. In conclusion, for Korean patients with two more recurrences of AUC in the past year, it is strongly recommended to perform an antimicrobial sensitivity test with a urine sample before empirical treatment.
Acute Disease ; Adolescent ; Adult ; Aged ; Ampicillin/pharmacology ; Anti-Bacterial Agents/pharmacology ; Cefazolin/pharmacology ; Ciprofloxacin/pharmacology ; Cystitis/*microbiology ; *Drug Resistance, Bacterial ; Escherichia coli/*drug effects/isolation & purification ; Female ; Humans ; Microbial Sensitivity Tests ; Middle Aged ; Prospective Studies ; Republic of Korea ; Risk Factors ; Trimethoprim-Sulfamethoxazole Combination/pharmacology

OBJECTIVEPseudomonas aeruginosa is an important cause of nosocomial infection, severe sepsis and death which associated with a trends of rising rates of resistance to a broad array of antimicrobial agents. To explore a feasible treatment protocol for such patients, we analyzed the susceptibility patterns of Pseudomonas aeruginosa in pediatric intensive care unit (PICU).

METHODThe age distribution, outcome of patients, sources of strains and susceptibility patterns of Pseudomonas aeruginosa in PICU from Jan 1, 2007 to Dec 31, 2011 were analyzed. Susceptibility to amikacin, piperacillin/tazobactam, aztreonam, ampicillin, ciprofloxacin, imipenem, meropenem, cefepime, cefoperazone, cefotaxime, ceftriaxone, ceftazidime, cefoperazone/sulbactam, cephazolin, cefuroxime, and polymyxin were determined by the disk-diffusion technique (K-B test method) and broth microdilution. P. aeruginosa ATCC 27853 was used as reference strain.

RESULTSeventy-five patients were Pseudomonas aeruginosa positive. 26(34.7%) were < 6 m, 49 (65.4%) were < 2 y. The percentages of cases who were Pseudomonas aeruginosa positive in different age groups in the same time was basically similar; 18 (24.0%) cases died. Pseudomonas aeruginosa accounted for 10.9% of G(-) germs, 6.5% of all pathogens in 2010 - 2011. Of the 126 strains, 83 (65.9%) were from sputum sample, 31 (24.6%) were from catheter sample of tracheal cannula, 10 (7.9%) were from blood sample and 2 (1.6%) were from secretion sample. The sensitivity to antibiotics of Pseudomonas aeruginosa in pediatric common treatments was 72.4% to cefoperazone/sulbactam, 71.5% to meropenem, 48.4% to imipenem, 66.7% to ceftazidime, 49.2% to piperacillin/tazobactam. Absolute resistance to ampicillin, cephazolin, cefuroxime and cefotaxime. Multiple-drug resistance was still severe, but a decreasing tendency was observed, 90.5% in 2007, 81.3% in 2008, 51.1% in 2009, 53.8% in 2010, 33.3% in 2011. Pan-drug resistance in different years was similar, 12.5% in 2008, 2.2% in 2009, 7.7% in 2010, 6.7% in 2011.

CONCLUSIONThe condition of drug resistance of Pseudomonas aeruginosa was still rigorous, we should conduct surveillance and prevent abusing antibiotics in order to avoid exacerbating drug resistance. We should improve testing technique, early and appropriate empirical antibiotics therapy is crucial according to clinical experience and antibiotic sensitivity. The effective treatment of P. aeruginosa is paramount to prevent multidrug resistance. The use of combination therapies for P. aeruginosa infection has been a long-advocated practice. To prevent hospital acquired cross infection, health care workers must pay close attention to hand sanitation and sterile operation strictly.

Adolescent ; Ampicillin ; pharmacology ; Anti-Bacterial Agents ; pharmacology ; Cefazolin ; pharmacology ; Child ; Child, Preschool ; Cross Infection ; microbiology ; prevention & control ; Drug Resistance, Multiple, Bacterial ; Female ; Humans ; Imipenem ; pharmacology ; Infant ; Intensive Care Units, Pediatric ; Male ; Microbial Sensitivity Tests ; Pseudomonas Infections ; drug therapy ; microbiology ; Pseudomonas aeruginosa ; drug effects ; isolation & purification