Objectives Multidrug resistance (MDR) and emergence of extended-spectrum β-lactamases (ESBLs) among uropathogenic Escherichia coli have been reported worldwide, but there was no information on the detection of blaCTX-M-15 in major teaching hospitals in Libya. The aim of the study was to investigate the occurrence of CTX-M-15 β-lactamases producers isolated from five teaching hospitals in Tripoli, Libya. Methods A total of 346 urine samples were collected from hospitalized patients in five teaching hospitals with a diagnosis of urinary tract infection (UTI). Phenotypic confirmation of ESBLs was confirmed by E-test strip; all ESBL-producing E. coli isolates were screened for the blaCTX-M-15 gene. Results The distribution of ESBL-producing E. coli varied among the five hospitals. The highest proportion was identified in Tripoli Medical Centre (67.6%). There were extremely high proportions of isolates resistant to ceftriaxone, cefepime, and ceftazidime (93.0–100.0%) among ESBL producers compared to non-ESBL producers (2.2–4.7%). MDR was detected in 22.2% of isolates. The majority of isolates (85.9%) in which blaCTX-M-15 was identified were ESBL producers. There was a correlation (p < 0.001) between expression of CTX-M-15 and resistance to ceftazidime. Conclusions The isolation of MDR ESBL-producing uropathogens expressing the CTX-M-15 gene will limit the choices clinicians have to treat their patients with UTIs. Continued surveillance and implementation of efficient infection control measures are required. arabic 17 English 94
Abdulaziz Zorgani, Abdulla Bashein(1-2017)

Acinetobacter baumannii is an opportunistic pathogen causing various nosocomial infections. The aim of this study was to characterize the molecular support of carbapenem-resistant A. baumannii clinical isolates recovered from four hospitals in Tripoli, Libya. Bacterial isolates were identified and antibiotic susceptibility testing was per-formed using automated system. Carbapenem resistance determinants were studied phenotypically using two dif-ferent techniques: E-test; chromogenic culture media. Polymerase chain reaction (PCR) amplification was used to determine the presence of bla OXA23 and blaOXA51 genes among isolates. A total of 119 isolates were characterized, overall the resistance prevalence was extremely high for aminoglycosides (79-96.6%), fluoroquinolones (94-96%), cephalosporins (96.6-100%) and carbapenemes (93.2-100%), all isolates were susceptible to colistin. In addition, 97.5% of isolates were identified as multidrug resistance (MDR). Varying degree of phenotypic detection of car-bapenemes was determined; highest levels of carbapenemes were detected using chromogenic media (76.5%) com-pared with E-test (45.4 %). The carbapenem resistance-encoding genes detected were blaOXA23 (84%) and blaOXA51 (73.1%); the highest occurrence of blaOXA23 was demonstrated in Tripoli’s Central Hospital (5/5; 100%) then in Tripoli Medical Center (44/51; 86.27%). The co-occurrence of these genes was demonstrated in (75/119; 63%) showing dissemination of carbapenemes resistance MDR A. baumannii in hospitals. This study shows that the high prevalence of OXA-23 contribute to antibiotic resistance in … arabic 14 English 113
Nada Elgrew, Abdulla Bashein(1-2016)

Every organism has deoxyribonucleic acid (DNA) within their cells. DNA is a complex molecule that contains all of the information needed to build and maintain living organisms. Extraction of deoxyribonucleic acid (DNA) is one of the most basic and critical steps affecting molecular-based techniques in the study of DNA that allow vast advances in genetic, molecular biology, biotechnology, forensic, and bioinformatics laboratories. Therefore, researchers have been used different modified and optimized protocols for efficient genomic DNA extraction from biological samples. Due to the high amount of genetic material in whole blood samples so it's one of the main sources used to obtain DNA and there are many different protocols available in this issue. In the present study, we optimized, evaluated by comparison to phenol-chloroform (traditional method) and silica column (QIAamp DNA Blood Mini Kit) DNA extraction procedures. The extracted DNA by these protocols was analyzed according to their time consuming, quality, quantity, cost and toxicity. Extracted DNA with current protocol was qualified using gel electrophoresis, Nanodrop spectrophotometric analysis. Our results showed that there are not significantly differences between these methods about DNA Purity (A260/A280) and DNA yield (ng DNA/μl). In addition, phenol/chloroform (traditional method) was the most toxic method; it takes more time but cheaper than other method; it yielded reasonably good quantities of good quality DNA and would be suitable for large-scale genotyping of blood samples. The silica column method (QIAamp DNA Blood Mini Kit) was the most expensive among the other method but the least extraction time was required and it was the safest method. arabic 11 English 69
Ghada Salem, Ahmed Zaid(1-2018)