Extended Spectrum β-lactamases and antimicrobial susceptibility among clinical isolates of Pseudomonas aeruginosa in the West Bank, Palestine

Objectives: Class D oxacillinases are frequently acquired by gram negative bacteria in general and P. aeruginosa in particular.P. aeruginosa is commonly implicated in causing nosocomial infections. The evolution of antibiotic resistance inP. aeruginosa and the acquisition of blaOXA genes interfere with successful treatment.Methods: A total of 49 clinical isolates of P. aeruginosa were obtained from Rafidia Hospital, West Bank, Palestine.Antimicrobial susceptibility testing of the isolates was performed by the standard disc diffusion method following theguidelines of CLSI. The prevalence of class D β-lactamases (OXA groups I, II and III) as well as the pseudomonas specificenzymes (CARB-3) were determined by PCR.Results: Susceptibility of P. aeruginosa to carbapenems was the highest 89%, and lowest to ticarcillin/clavulanic acid70%. This study revealed that P. aeruginosa produced oxacillinase enzymes at rates of: OXA-10 (40.8%), OXA-2 (20.4%)and OXA-1 (18.4%). All ceftazidime resistant strains expressed OXA-1 and OXA-2, 18.4%. PSE group was expressed in10.2%.Conclusions: This is the first research conducted to investigate the correlation between OXA genes (blaOXA-1, bla-OXA-2 and blaOXA-10) and antimicrobial resistance among P. aeruginosa clinical isolates in Palestine. The results obtainedcould contribute to better treatment and reduction of the evolution of resistant strains. In addition, it will provideimportant information regarding the geographical distribution of class D β-lactamases. J Microbiol Infect Dis 2013; 3(2):56-60Key words: P. aeruginosa, β-lactamase, susceptibility, oxacillinases, blaOXA gene

Anticancer, antibacterial, and antifungal activities of arum palaestinum plant extracts

Traditional natural remedies have long played an important role in the treatment of cancer and infectious diseases. A part from the high cost and undesirable side effects associated with synthetic drugs, increased interest has intensified to determine the biological effects of plant extracts on malignant cells as alternative for conventional drugs used in the markets. The medicinal properties of Arum Palaestinum Boiss were in-vitro investigated in this research project. Arum palaestinum is chosen based on its use in traditional palestinian herbal medicine. The leaves of this plant were air dried in the shade and then three types of extract were obtained and their antimicrobial and for anticancer activity testing. Investigations on three different cancer cell lines (C2Cl2, 3T3-L1, Hela) revealed direct inhibitory effect of the extracts. This effect differs according to concentrations used. Aqueous boiled extract was more effective at lower extract concentrations as compared to other two extracts. Arum palaestinum plant extracts showed no inhibitory effect on bacterial species (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) as well as yeasts (Candida albicans). In conclusion, Arum palaestinum has potentially anticancer effect. Further investigations are required to confirm this conclusion and to elucidate the mechanisms of actions and toxicity of this herb

Molecular characterization and antibiotic susceptibility profiles of Helicobacter pylori isolated from patients with Gastrodeudenal diseases in Jordan

Introduction:  Helicobacter pylori is a major cause of more than 80% of chronic active gastritis and other gastrodeudonal diseases worldwide. Successful treatment of H. pylori routinely requires the use of multiple agents with different mechanisms including compounds inhibiting acid secretion in conjunction with antibiotics. However, recent data showed the emergence of resistant clinical strains particularly against metronidazole and clarithromycin. The aim of this study is to determine the prevalence of and the susceptibility of H. pylori isolates recovered from patients with gastrodeudonal diseases to several antimicrobial agents. Materials and Methods: A prospective study has been conducting on Jordanian patients attended the gastrointestinal unit of the Jordan university hospital starting from 2014-2015 with gastroduodenal diseases. Antral and corpus mucosal biopsies from the stomach of each patient were used for the isolation of H. pylori on selective culture media. Presumptive H. pylori colonies were subsequently confirmed by biochemical tests and standard 16S rDNA PCR assay. The antimicrobial susceptibility testing was performed by standard agar diffusion methods according to CLSI. Subsequently, MICs were determined by E test and standard agar dilution method. Molecular typing of the clinical strains was performed using multiplex PCR for the detection of vacA and cagA genotypes. Metronidazole resistance was characterized by molecular methods for the detection of rdxA gene mutations. Results: Among 72 symptomatic patients, 13 (23%) patients showed positive H. pylori infection by both rapid urease test and culture. The antibiotic susceptibility profile showed that all of the isolates were sensitive to amoxicillin.  Resistance to, clarithromycin, ciprofloxacin and levofloxacin were observed in 15%, 23% and 8% of the isolates respectively while 92% of the strains were resistant to metronidazole (MIC ≥ 32 ug/ml). Metronidazole resistance due to mutations in rdxA gene was only observed in one strain (8%) suggesting other resistance mechanisms. Correlation between antibiotic resistance and virulence factors was statistically not significant (p > 0.05). Conclusion: The present study showed that the prevalence of metronidazole resistance among clinical isolates of H. pylori is very high. Lower resistance to other antibiotics are reported. Concern should be taken into consideration when triple therapy is used for the treatment of H. pylori in our region

The Prevalence and Molecular Distinguishing of Brucella melitensis Rev1 Strain among Field Isolates the Brucella from Sheep and Goat Milk through PCR-RFLP Analysis of omp2 Gene Polymorphism

The present study was undertaken to characterize the prevalence and molecular distinguishing of Brucella melitensis field and vaccine Rev1 strains isolated from milk among the sheep and goat population. The study was carried out on flocks of sheep and goats suffering from Brucella infection outbreaks. A total of 171 milk samples were collected from different districts of the West Bank, part of Palestine, and isolated on Brucella agar. 86 cultures were confirmed by standard biochemical methods and screened for Brucella melitensis 16M of IS711 element by a conventional PCR technique. All these samples were also amplified for the omp2 gene to identify differences between field and Rev 1 strains in an infected flock. The results obtained from the PstI restriction enzyme pattern revealed that only 2 (4.5%) samples have specific polymorphism accomplished with the Brucella melitensis Rev1 strain. All other samples were restricted according to the Brucella melitensis 16M polymorphism pattern and originated from nonvaccinated flocks. Despite the adverse side effects of the Brucella melitensis vaccine, only a well-organized whole-flock vaccination and awareness campaign may inhibit the virulence of the field strain and, subsequently, reduce the prevalence of brucellosis infection among animals and humans in Palestine

Novel Fusidic Acid Cream Containing Metal Ions and Natural Products against Multidrug-Resistant Bacteria

Background: Drug design and development to overcome antimicrobial resistance continues to be an area of research due to the evolution of microbial resistance mechanisms and the necessity for new treatments. Natural products have been used since the dawn of medicine to heal skin infections. The antimicrobial properties of fusidic acid, zinc sulfate, and copper sulfate have been studied and are well known. Furthermore, these compounds have different mechanisms of action in targeting microorganisms, either by inhibiting protein synthesis or bacterial cell walls. Therefore, their combination is expected to have synergistic activity in killing bacteria. However, the synergistic antimicrobial activity has not been evaluated in a cream formulation. Therefore, the objectives of this in vitro study were to develop and evaluate the synergistic efficacy of fusidic acid in combinations with natural products, including oleuropein, thyme oil, zinc sulfate, and copper sulfate, as a cream to eradicate fusidic-acid-resistant microorganisms in skin infections. Methods: Three different cream formulations were developed, compared, and labeled F1, F2, and F3. The compounds were studied for their antibacterial activity. In addition, the stability of the cream was investigated at 25 °C and 40 °C in plastic jars over three months. Results: The F2 formula has adequate physicochemical properties. Furthermore, it displays stable and better results than the marketed trade product and has potential inhibition zones (ZOI). Interestingly, considerable numbers (9.5%) of fusidic-acid-resistant Staphylococcus aureus (FRSA) isolates possessed a high resistance pattern with MIC ≥ 128 μg/mL. In contrast, most tested FRSA isolates (90.5%) had a low resistance pattern with MIC ≤ 8 μg/mL. Conclusion: In conclusion, the F2 cream made with fusidic acid, oleuropein, thyme oil, zinc sulfate, and copper sulfate in the right amounts has stable physical and chemical properties and has potential against FRSA as an antimicrobial agent