Biomedical subjects

E E Udo

Publications and source records attributed to E E Udo.

43 records · Page 3Linked to original sources

PubMed1990

Conjugal transfer of plasmid pWBG637 from Staphylococcus aureus to Staphylococcus epidermidis and Streptococcus faecalis.

Plasmids pWBG636 (GmR) and pWBG642 (EmR) derived from the conjugative plasmid pWBG637 were tested for ability to transfer conjugatively to Staphylococcus epidermidis, Streptococcus faecalis, Bacillus subtilis and Escherichia coli. Both plasmids transferred to S. epidermidis and Strept. faecalis but not to B. subtilis and E. coli. Once in S. epidermis and Strept. faecalis they were transferred back to S. aureus. Restriction endonuclease analysis showed that the plasmids were stably maintained in S epidermidis and Strept. faecalis.

Conjugation, Genetic↗

PubMed1990

A new class of conjugative plasmid in Staphylococcus aureus.

Plasmid pWBG637, a Staphylococcus aureus conjugative plasmid having no known resistance phenotype, was compared with other conjugative plasmids in S. aureus by restriction endonuclease analysis, incompatibility testing and DNA-DNA hybridisation. It differed from the other conjugative plasmids on all three criteria and thus belongs to a new class of conjugative plasmids.

DNA Restriction Enzymes↗

PubMed1990

Excision of a conjugative plasmid from the staphylococcal chromosome.

Staphylococcus aureus isolate WBG1003 resistant to benzyl penicillin, cadmium, arsenate and streptomycin harbours two plasmids of 38.8 (pWBG621) and 4.4 (pWBG625) kb. In conjugation experiments two types of streptomycin-resistant transconjugants were obtained; one carried a 4.4-kb plasmid and the other, a 34.5-kb and a 4.4-kb plasmid. The 34.5-kb plasmid (pWBG620) has been found to be conjugative and able to mobilise non-conjugative plasmids. It has no detectable resistance phenotype and has not been detected in WBG1003 nor in the recipient used in the conjugation experiments. Restriction endonuclease analysis and DNA-DNA hybridisation have revealed that pWBG620 is unrelated to pWBG621 present in strain WBG1003. The data presented indicate that pWBG620 is in the chromosome of strain WBG1003 and that it excises during conjugation.

Blotting, Southern↗

PubMedDate not supplied

Molecular fingerprinting of mupirocin-resistant methicillin-resistant Staphylococcus aureus from a burn unit.

OBJECTIVES: To characterize mupirocin-resistant methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients in a burn unit by pulsed-field gel electrophoresis and plasmid contents. METHODS: A total of 53 methicillin-resistant S. aureus, consisting of 48 mupirocin-resistant and 5 mupirocin-susceptible MRSA were compared by plasmid content and pulsed-field gel electrophoresis of Sma I digested genomic DNA. RESULTS: Of the 48 mupirocin-resistant isolates, 39 expressed high-level, and 9 expressed low-level mupirocin resistance. Plasmids were detected in all of the 53 isolates; however, only the high-level mupirocin-resistant isolates contained a 38 kb-conjugative plasmid that encoded high-level mupirocin resistance. Pulsed-field gel electrophoresis divided the isolates into four patterns designated types I to IV. Forty-three isolates consisting of 34 high-level, 5 low-level mupirocin-resistant and 4 mupirocin-susceptible isolates defined the type-I pattern. Eight isolates, five high-level and three low-level mupirocin-resistant isolates had the type-II pulsed-field pattern. The type-III and type-IV pulsed-field patterns consisted of a single isolate each. The type-I and type-II pulsed-field patterns were related and only differed by four Sma I bands. CONCLUSIONS: Results of typing the mupirocin-resistant MRSA from the burn unit with pulsed-field gel electrophoresis indicated that closely related MRSA clones previously circulating in the unit had acquired a high-level mupirocin-resistant plasmid, and spread aided by mupirocin use.

Anti-Bacterial Agents↗

PubMedDate not supplied

Point surveillance of Staphylococcus aureus carriage among medical staff in Infectious Diseases Hospital, Kuwait.

OBJECTIVE: To investigate the carriage of Staphylococcus aureus among doctors and nurses in Infectious Diseases Hospital, Kuwait, following the detection of 3 cases of methicillin-resistant S. aureus (MRSA). MATERIALS AND METHODS: A total of 260 nasal and throat swabs were obtained from 19 doctors and 111 nurses and cultured for the carriage of S. aureus. Forty-three S. aureus were identified based on their growth characteristics on mannitol-salt agar, catalase and tube coagulase and DNA hydrolysis. The isolates were tested for susceptibility to antibacterial agents and typed by phage typing; plasmid analysis and pulsed-field electrophoresis were carried out to determine their relatedness. RESULTS: Of the 19 doctors, 4 (21%) had nasal carriage while only 1 of them had a throat carriage. Sixteen (14.4%) nurses carried S. aureus in their noses and 20 (18%) in their throats. The combined nasal carriage rate for both doctors and nurses was 15.8%, and combined throat carriage was 16.6%. None of them carried MRSA. The isolates were resistant to penicillin G (90%), tetracycline (23.3%), erythromycin (9.3%) and cadmium (100%). Typing of the isolates showed a variety of phage types, plasmid and pulsed-field gel electrophoresis patterns. DISCUSSION: None of the doctors or nurses carried MRSA. Typing of the methicillin-susceptible strains that they carried demonstrated that the S. aureus were different, indicating an absence of a dominant clone capable of spreading. It is important to maintain a low carriage of S. aureus among health-care workers.

Bacteriophage Typing↗

PubMedDate not supplied

Etiology and antibiotic susceptibility patterns of community-acquired urinary tract infections in a Kuwait hospital.

OBJECTIVE: The aim of this study was to determine the distribution and antibiotic susceptibility patterns of bacterial strains isolated from patients with community-acquired urinary tract infections (UTIs) at the Infectious Diseases Hospital, Kuwait. MATERIALS AND METHODS: The study was conducted over a 7-year period. Patient information was obtained from medical record files. Antibiotic-sensitivity testing was performed by disk diffusion. E test and double disk diffusion methods were used to study the production of extended spectrum beta-lactamases. RESULTS: Of the 14,042 urine samples processed, significant bacteriuria (>10(5) cfu/ml) was detected in 1,606 (11.4%). The majority (74.5%) of the isolates were from women while the remaining 25.5% were from men. The majority of infections (75%) were due to Enterobacteriaceae, coagulase-negative staphylococci (10.3%) and group B streptococci (8.7%). Among the gram-negative enteric bacilli high prevalence of resistance to ampicillin, amoxicillin/clavulanic acid, cephalothin, and trimethoprim/sulfamethoxazole was observed. Increasing resistance to ciprofloxacin and gentamicin was observed in E. coli isolates over the 7 years. Multiple resistance was detected in 53.8 and 41% of E. coli and Klebsiella spp. strains, respectively. No glycopeptide-resistant enterococci were isolated. CONCLUSION: This study revealed that Enterobacteriaceae were the predominant bacterial pathogen of community-acquired UTIs in Infectious Diseases Hospital, Kuwait. It also demonstrated an increasing resistance to ciprofloxacin, gentamicin and the production of extended spectrum beta-lactamase among UTI pathogens in the community.

Adolescent↗

PubMedDate not supplied

Molecular diagnosis of antimicrobial resistance.

Advances in molecular technology have helped in better understanding of mechanisms and diagnosis of diseases in many medical fields. Several molecular techniques are available for determining the genotypic drug-resistance and monitoring epidemic spread of a particular antimicrobial resistance gene in a hospital or patient population. The molecular (genotypic) testing has several advantages over conventional (phenotypic) testing in being faster and unambiguous, more accurate, able to detect masked resistance and can serve as a "gold" or "reference" test for detecting antibiotic resistance genes. This article addresses these molecular tests with their application and limitations and provide examples of their use especially in Mycobacterium tuberculosis and methicillin resistant Staphylococcus aureus.

DNA, Bacterial↗