Rezvan Moniri

Aims: Acinetobacter baumannii could develop resistance through different mechanisms, leading to the emergence of strains resistant to all commercially accessible antibiotics. This research aimed to evaluate the antimicrobial resistance pattern and the prevalence of genes encoding quinolone resistance in quinolone-resistant isolates. Methods: In this study, 114 A. baumannii strains were ...

Background: Recent studies have shown an increasing incidence of antibiotic resistance in dacryocystitis. Management of diseases may include determining microbial agents and choosing appropriate antibiotics for treatment. Objectives: This study aimed to present the best treatments for dacryocystitis. To this end, specimens' microbiology and antibiotic susceptibility were examined in patients with dacryocystitis in the microbiology laboratory of the Kashan University of Medical Sciences. Methods: This cross-sectional study was performed on 172 patients presenting with acute and chronic dacryocystitis at the Matini Hospital, Kashan, between 2017 - 2018. Patient characteristics, culture isolates, and antimicrobial susceptibility data were collected. The PCR assay of the mecA gene was performed in all methicillin-resistant Staphylococcus isolates. Results: The most common bacteria were coagulase-negative staphylococci (CoNS), Staphylococcus aureus, Pseudomonas aeruginosa, and Acinetobacter baumannii. The majority of the isolated microbes were sensitive to rifampicin, linezolid, amikacin, and gentamicin. In Gram-negative bacilli, nine of the isolates were extended-spectrum beta-lactamase positive. The PCR test showed the frequency of mecA gene of resistant S. aureus and resistant CoNS isolates to be 40 and 46.3%, respectively. Conclusions: Coagulase-negative staphylococci were the most frequently isolated bacteria. The highest antibiotic susceptibility was observed to rifampin, linezolid, amikacin, and gentamicin. A high percentage of CoNS carried the mecA gene.

Objective: To determine epidemiological, molecular characterization, and potential risk factors of human brucellosis. Methods: This descriptive study was carried out in the clinical setting in Iran between 2017 and 2018. A total of 297 participants enrolled in the study. The sample size was calculated based on the occurrence rate of brucellosis in different areas. Patients were assessed using serological tests and conventional culture methods. Phage and multiplex PCR methods typed all of Brucella isolates. Potential risk factors of disease were determined. Results: A total of 141 of 297 (47.5%) Brucella strains were isolated and all of them were detected as Brucella melitensis biovar 1. Based on serologic titers, high culture positivity was recorded at 1/640 titer (PBrucella species by the multiplex PCR. Brucella melitensis biovar 1 is still the dominant causative agent in Iran. The consumption of unpasteurized dairy products, living in rural areas, and animal contact were risk factors of brucellosis.

To characterize the resistance patterns of uropathogenic Escherichia coli (UPEC) in a Tertiary Teaching Hospital in Iran, we conducted a descriptive epidemiology study using molecular techniques. The subjects consisted of patients having acute urinary tract infection, who were enrolled in the study from 2014 to 2017. The antimicrobial susceptibility profile of 101 UPEC isolates was determined by Kirby-Bauer disc diffusion method. Extended spectrum β-lactamase (ESBL) was detected by the double-disk synergy test. Biofilm formation was done using microtiter plates. The presence of virulence genes ( pai , pap , hly , traT , pai , cnf-1 , sfa , and afa ) was evaluated by a PCR. Molecular typing of UPEC E. coli isolates was performed with fimH and multilocus sequence typing (MLST). 70.3% of isolates were multidrug-resistant. 37.6% of isolates were Extended spectrum β-lactamases (ESBLs) producer. Strong biofilm formation was seen in 27.7%. Forty-seven different fimH allelic variants were identified. Among identified fimH allelic variants, the most common types were f1 (18.8%) and f14 (18.8%). ST131 (54.5%) was the most prevalent clonal group significantly correlated with the pai gene. Seven sequence types (STs) were detected only once (ST405, ST410, ST450, ST636, ST648, ST1193, and ST6451). Clonal groups showed no significant differences in terms of antibiotic resistance patterns. There was no significant difference between virulence genes and antibiotic resistance patterns in the studied clonal groups. To our knowledge, the present study is the first study in Iran that investigated the genotypic diversity of UPEC isolates by MLST and fimH typing methods. The two methods might serve as a useful molecular test for surveillance and epidemiological studies of isolates.

Diagnosis of human brucellosis still challenges clinicians and scientists with several considerable aspects, particularly in endemic countries. The current study aimed at reviewing laboratory tests in the diagnosis of human brucellosis.A literature search was conducted in PubMed, Scopus, Thompson Reuters, and Mesh databases using keywords for articles published until December 2018. Seventy studies were selected for data collection.The current inclusive review included information about the currently used advanced diagnostic tests to confirm the detection of human brucellosis.The article reviewed the methods for the diagnosis of human brucellosis and summarized developments for the future.

Introduction: The bacterial enzyme has gained more attention in therapeutic application because of the higher substrate specificity and longer half-life. L-asparaginase is an important enzyme with known antineoplastic effect against acute lymphoblastic leukemia (ALL). Methods: Novel L-asparaginase genes were identified from a locally isolated halo-thermotolerant Bacillus strain and the recombinant enzymes were overexpressed in modified E. coli strains, OrigamiTM B and BL21. In addition, the biochemical properties of the purified enzymes were characterized, and the enzyme activity was evaluated at different temperatures, pH, and substrate concentrations. Results: The concentration of pure soluble enzyme obtained from Origami strain was ~30 mg/L of bacterial culture, which indicates the significant improvement compared to L-asparaginase produced by E. coli BL21 strain. The catalytic activity assay on the identified L-asparaginases (ansA1 and ansA3 genes) from Bacillus sp. SL-1 demonstrated that only ansA1 gene codes an active and stable homologue (ASPase A1) with high substrate affinity toward L-asparagine. The Kcat and Km values for the purified ASPase A1 enzyme were 23.96s-1 and 10.66 µM, respectively. In addition, the recombinant ASPase A1 enzyme from Bacillus sp. SL-1 possessed higher specificity to L-asparagine than L-glutamine. The ASPase A1 enzyme was highly thermostable and resistant to the wide range of pH 4.5–10. Conclusion: The biochemical properties of the novel ASPase A1 derived from Bacillus sp. SL-l indicated a great potential for the identified enzyme in pharmaceutical and industrial applications.