Objective To study the restraining capability mechanism of small calibre ileum conduit anastomosed directly to the bladder in pigs. Methods 15 pigs were randomized into 5 groups according to the length of the ileal loop to form the conduit: 4cm, 5cm, 6cm, 7cm, and 8cm. In each pig, two ileal segments of the same length were reduced in calibre by opening up longitudinally and closed around a catheter. They were then directly anastomosed to the bladder end to side and placed within rectus abdominis musche in each pig. Urodynamic test, radiological image analysis and histological study were carried out 8 weeks after the procedure. Results No stenosis and twisting of the ileal ileum conduit were observed in 5cm, 6cm, and 7cm groups, in which they could be catheterized with ease. When the bladder was filled with a mean volume of 400ml of saline, the maximum "urethral" pressure ranged from 5.15～12.19kPa and the maximum close pressure (MCP) ranged from 4.83～11.27kPa. The "urethral functional length" of the ileal conduit was longer than 2cm. Among 5cm, 6cm and 7cm groups, there were no significant differences in maximum closure pressure and the urethral functional length, except in maximum "urethral" pressure. In the 4cm group, there was incontinence. Failure was found in the 8cm group because of necrosis of the ileal loop embedded in the abdominal muscle. Conclusion Small calibre conduits formed with ileum in the length of 5cm to 7cm are able to restrain urinary leakage when anastomosed directly to the bladder and and embedded in the by rectus abdominis in pigs.

OBJECTIVE To understand the pathogenicity of Staphylococcus epidermidis causing urinary tract infection. METHODS Thirty five isolates were collected in the patients with urinary tract infection during 2003-2004 to test the minimal inhibitory concentration(MIC) to erythromycin,ampicillin,cefoxitin,ceftriaxone,teicoplanin,ciprofloxacin,tetracycline,trimethoprim-sulfamethoxazole and vancomycin.The genes of ermA,ermB,ermC,msrA,mecA,and icaA were amplified by PCR.The biofilm producing of the isolates was determined by the quantitative method.The pulsed-field gel electrophoresis(PFGE) was used to discriminate the homology among the isolates. RESULTS Among the isolates,MRSE accounted for 71.4%.The antibiotic susceptibility to erythromycin,ampicillin,ceftriaxone,ciprofloxacin,tetracycline and trimethoprim-sulfamethoxazole were 22.8%,6.34%,34.9%,26.9%,44.4% and 62.2%,respectively,whereas to teicoplanin and vancomycin were 99.2% and 100%.All the isolates resistant to cefoxitin carried mecA.ermC Was the predominant determinant among the erythromycin resistant isolates.Among the 14 icaA positive isolates,10 isolates were biofilm producing.All the isolates were classified into 18 types by PFGE. CONCLUSIONS The high and multiple antibiotic resistance of S.epidermidis isolates causing urinary tract infection were shown.The detection of icaA gene in clinical S.epidermidis isolates was a signal of their pathogenicity.

OBJECTIVE To give experimental basis for further investigation on Staphylococcus epidermidis biofilm resistance,we investigated the erythromycin repression of the planktonic,resuspended and biofilm cells.METHODS log Reduction of the planktonic,resuspended and biofilm cells of S.epidermidis strain 1457 and wild isolate S 68 was tested under 100 MIC erythromycin.The cells inside biofilm were observed by transmission electron microscope.RESULTS log Reduction of the planktonic and resuspended cells of S.epidermidis 1457 were 5.56?0.11 and 5.28?0.08,respectively,after 4h under 100 MIC erythromycin,which was higher than that of biofilm cells(P0.05).The tendency of the log reduction of isolate S 68 was the same as that of strain 1457.The cells of biofilm without erythromycin were spherical and of even distributed,but the swelling,liquefied cells and cell debris were observed in the biofilm with erythromycin after 12h.The arrangement of cells inside biofilm with erythromycin was looser than that without erythromycin.CONCLUSIONS The erythromycin resistance of biofilm cells is higher.Biofilm can give protection for the bacteria to avoid the killing of action by antibiotics.

OBJECTIVE To explore the relationship between urinary tract infection(UTI) and urological surgical site infections(SSI).METHODS The surgical site infections of 115 patients underwent urological operations were observed.Patients were screened for the presence of UTI before the operation and subcutaneous swabs for culture were collected at the end of the operation by brushing with a sterile cotton-swab just before skin closure.The resistance and similarity of the isolates were analyzed by antimicrobial susceptibility test and pulsed field gel electrophoresis(PFGE).RESULTS Surgical site infection occurred in 14 of 115 patients.The isolates from infected surgical sites showed higher resistance to antimicrobial agents than those from non-infected surgical sites(P