16 research outputs found
Prevalence of cagA, cagT, cagE, vacA and hrgA genes in Helicobacter pylori strains isolated from patients with gastric cancer in Karaj city, 2016
Background: It is estimated that approximately half of the planet's population is infected with Helicobacter pylori and 70-60 of the infections in the Western countries are caused by cagA-positive strains. The aim of this study was to determine the frequency of cagA, cagT, cagE, vacA and hrgA genes in H. pylori isolated from patients with gastric cancer. Materials and Methods: A total of 50 non-repetitive biopsy samples were collected from patients undergoing endoscopy in the endoscopic center of the Shahid Fayaz Hospital in Karaj. The presence of cagA, cagT, cagE, vacA and hrgA genes was determined using the multiplex PCR method. Results: Of the 50 gastric biopsies, 44 samples (88) were positive for the presence of various virulence genes. The molecular analysis of virulence factors showed that the prevalence rates of cagA, cagT, cagE, vacA and hrgA genes were 16 (32), 8 (16), 13 (26), 7 (14) and 17 (34), respectively. There was a significant relationship between sex, smoking and gastric ulcer with some genes, but no significant relationship was found between the family history and age group with any of the genes. Conclusion: The presence of various pathogenic genes has a significant effect on gastric ulcer, duodenal ulcer and gastric cancer. The effects of other genes, such as hrgA, are important in tissue damage and inflammatory responses
Molecular investigation of CTX-M gene in Extended Spectrum β Lactamases (ESBLs) producing Pseudomonas aeruginosa isolated from Iranian patients with burn wound infection
Background: Pseudomonas aeruginosa (P. aeruginosa) is one of the most important causes of infection in burns and intensive care units. Extended-spectrum β-lactamases (ESBLs) production in P. aeruginosa is a major factor in the antibiotic resistance and is thought of as a serious threat to the currently available antibiotic armory. The purpose of this study was to determine the prevalence of CTX-M gene in ESBL-producing P. aeruginosa isolates in burn wound samples.Materials and methods: In this cross-sectional survey, a total of 60 clinical isolates of P. aeruginosa were obtained from patients suffering from burn wound infection referred to major hospitals of Tehran, Iran. After verification by biochemical tests and antimicrobial susceptibility testing, CTX-M gene was identified using PCR method.Results: The results of the molecular analysis of CTX-M gene showed that the prevalence of isolates of P. aeruginosa harboring CTX-M gene was 20% (12/60).Conclusion: The results from this study showed high levels of antibiotic resistance and CTX-M gene among P. aeruginosa isolated samples of burn-wound infections which condition may result in the increased the emergence of multidrug-resistant strains and the failure of therapy This study suggests that detailed data on the CTX-M gene frequency can be useful to achieve the best therapy for infections caused by ESBLs producing P. aeruginosa
Classification and identification of human papillomavirus based on its prevalence and development of cervical lesion among Iranian women
Introduction: Cervical cancer is the most common female cancer in large areas of the developing world, and almost half of these cases (54%) arises in Asia, where cervical cancer is still threatening women’s health and survival, which makes it a considerable public problem. Human papillomavirus (HPV) is one of the most powerful human carcinogens. Today, it has been proven that all cervical cancers and primary precancerous lesions are caused by carcinogenic types of HPV infections. HPV genotyping can therefore evaluate the screening programs. Methods: Five hundred fifty women referring to the gynecological centers were subjected to Pap smear cell samples. The cytopathological diagnosis of obtained cervical samples was based on the Bethesda system. HPV genotyping was carried out using the INNO-LiPA HPV Genotyping Extra II Amp assay. Results: In a total of 244 HPV positive cases, single‑type HPV infecÂtion was observed in 49.6%, while multi‑type HPV infections (including ≥ 2 types) were found in 45.5% of cases. Among the 110 cases with abnormal cytology results, going-over analyses led to the identification of atypical squamous cell of unknown significance (ASCUS) in 73 cases, low‑grade squamous intraepithelial lesions (LSIL) in 24 cases, and high‑grade squamous intraepithelial lesion (HSIL) in 12 cases. In these groups, the infection rate of high-risk HPV (HR-HPV) was 89%, 82%, and 100%, respectively. Conclusion: In this study, the total population of women suffering from different cervical lesions and malignancy was found to be infected with various HPV genotypes. High prevalence of HPV- 53 and HPV- 16 detected among participants with normal cytology can be considered as a tip-off development of cervical cancer among Iranian women
Detection Rate of Metallo-β-Lactamase-Expressing Genes; blaVIM-1, blaVIM-2 and blaSPM-1 in Pseudomonas aeruginosa Isolates
Introduction: Imipenem-resistant Pseudomonas aeruginosa is an organism expressing metallo-β-lactamase (MBL) enzyme, and is a serious agent of hospital infection holding a serious universal therapeutic challenge. Carbapenems are potent options for the treatment of P. aeruginosa infections. The rate of MBLs expression has been variable among imipenem-resistant P. aeruginosa isolates. In the present study, we investigated the presence of MBL in the clinical isolates of P. aeruginosa. Methods: A total of 60 P. aeruginosa isolates were obtained from Kerman hospitals during 2014-2015. The antibiotics susceptibility was assessed using disk diffusion test. MBL positivity in P. aeruginosa was investigated using double disk synergy test (DDST) and polymerase chain reaction (PCR) with amplification of blaVIM-2, blaVIM-1 and blaSPM-1. Results: From 60 P. aeruginosa isolates, 28 (46.6%) were imipenem-resistant. Among these, 17 (60.7%) were identified as MBL-producing P. aeruginosa isolates using DDST. Results of PCR test demonstrated the existence of 8 (28.5%) P. aeruginosa, producing blaSPM-1. Conclusion: The frequency of blaSPM-1-producing P. aeruginosa isolates from Kerman Hospitals was relatively high. Therefore, it is recommended that the distribution of MBL-mediated resistances be managed
IMolecular Analysis of AmpC Genomic Polymorphism in Shigella Sonnei Isolated from CLinical Specimens by PCR-RFLP Method
Background & Objective: Shigella is a gram-negative bacillus that has caused serious infection problems in developed and developing countries. The existence of beta-lactamase genes such as AmpC in Shigella species in one country has led to a variety of antibiotic resistance patterns, which can have very serious health risks for the community. The aim of this study was to investigate the prevalence of AmpC β-lactamase gene in S. sonnei strains and determine the prevalence of a spot mutation in this gene by RFLP method.
Materials & methods: Sixty strains of S. sonei were detected using biochemical and microbiological tests. Subsequently, the amplification of ampC gene was performed by PCR method. Then, a point mutation analysis on this gene was performed on ampC gene positive strains. RFLP technique was performed using Hinf1 enzyme.
Results: Among 60 isolates, 30 (50%) isolates were positive for ampC beta-lactamase gene. Furthermore, A to G point mutation was detected in 11 (37%) ampC gene carrying isolates.
Conclusion: The results of this study showed an increasing rate in the prevalence of ampC gene and noticeable prevalence of A to G point mutation in the strains carrying this gene. This mutation may help increase resistance to cephalosporins
Detection of virulence genes in Uropathogenic E. coli (UPEC) strains by Multiplex-PCR method
Background & Objectives: Urinary tract infection caused by E. coli is one of the most common illnesses in all age groups worldwide. Presence of virulence genes is a key factor in bacterial pathogens in uroepithelial cells. The present study was performed to detect iha, iroN, ompT genes in the Uropathogenic E.coli isolates from clinical samples using multiplex-PCR method in Kerman.
Materials & Methods: In this descriptive cross-sectional study, 200 samples of patients with urinary tract infections in Kerman hospitals were collected. After biochemical and microbiological tests, all strains were tested with regard to the presence of iha, iroN, and ompT genes using multiplex-PCR method.
Results: The results of Multiplex-PCR showed that all specimens had one, two, or three virulence genes simultaneously. The highest and lowest frequency distribution of genes was related to iha (56.7%) and iroN (20%) respectively.
Conclusion: According to the prevalence of urinary tract infection in the community and distribution of resistance and virulence factors, the fast and accurate detection of the strains and virulence genes is necessar
Gene molecular study of biofilm of Staphylococcus aureus isolated from fresh milk using multiplex polymerase chain reaction
Background: Staphylococcus aureus is one of the main causes of food poisoning in the world. This pathogen has the ability to create biofilms that can lead to food contamination. The presence of biofilm genes in bacteria is very important. The aim of this study was to identify sticky genes (eno, cna, ebp, bbp) that play an important role in virulence and pathogenicity of the bacteria and even prevent the penetration of antibiotics in pathogenicity time.
Materials and Methods: A total of 100 samples of fresh milk were collected from live animals and 60 isolates were selected to identify sticky genes (eno, cna, ebp, bbp) in the production of biofilm of S. aureus using the multiplex polymerase chain reaction method. In addition, the frequency rates of S. aureus strains resistant and susceptible to antibiotics such as methicillin, vancomycin, and clindamycin were determined among the samples.
Results: From a total of 60 isolates of fresh milk, 43.4% of the colonies had laminin-binding protein gene or eno gene. Also, 90% of the isolates were sensitive to vancomycin, 50% sensitive to clindamycin and 43.4% sensitive to methicillin. Distribution rates of other sticky genes including ebp, cna, bbp were 11.6%, 20% and 25%, respectively. Molecular study results showed that the highest and lowest percentages of genes were related to the eno and bbp genes, respectively.
Conclusion: The present study shows that the maximum sensitivity of the samples (90%) was related to vancomycin and the least amount of sensitivity (43.3%) was related to methicillin
The Effect of Lactobacillus Casei-Free Floating Fraction on the Expression of Class I Integron Gene in Clinical Isolates of Acinetobacter Baumannii by Real Time PCR
Background & Objective: The most common way for the spread of resistance genes and the emergence of multidrug resistance (MDR)-Acinetobacter baumannii species is the presence of genetic elements called integrons. Therefore, in recent years, the use of probiotics has been recommended to reduce the complications of resistant bacteria and treatment failure. Therefore, the aim of this study was to investigate the effect of probiotic Lactobacillus casei supernatant on the expression of class 1 integron gene in A. baumannii isolates by Real time PCR.
Material & methods: Sixty clinical samples of blood, respiratory secretions, urine, and ulcers were collected from hospitals in Saveh, Iran. The presence of the intI gene was evaluated by PCR. After treatment with the sub-MIC strains of L. casei supernatant, mRNA was extracted and Real-time PCR was performed to determine the level of integron gene expression and finally the expression level was determined using Δct method. Expression analysis was performed by relative mRNA expression compared to the standard strain and it was performed in SPSS version 18 using t-test statistical analysis.
Results: Out of 12 isolates of A. baumannii, the prevalence of IntI gene was 100%. The fold change for the intI gene was -1.18, indicating that it decreased in the treated group compared to the untreated group (P <0.05).
Conclusion: The results showed that the probiotic supernatant was able to reduce the expression of the intI gene; therefore, the use of probiotics as a supplement or alternative therapy in the drug-resistance microbial infections is recommended
Detection Mycoplasma hominis and genitalium in Urine Samples from Athletes and Non-Athletes by Multiplex- PCR Method
Backgrounds and Objectives: Mycoplasmas are distinguished phenotypically from other bacteria by their minute size and total lack of a cell wall and are involved in urogenital infections in both male and females. The aim of this study was to evaluate the presence of Mycoplasma genus and Mycoplasma homonis and genitalium in urine samples of athletes and non-athletes.
Methods: In this study, urine samples were taken from 50 athlete and non-athlete males and were transported to laboratory. After DNA extraction, PCR was performed using specific primers to identify Mycoplasma genus and species hominis and genitalium.
Results: Among 100 samples, 5 were positive for Mycoplasma genus which all the 5 isolate belonged to non-athlete persons. In 5 positive samples, 3 belonged to Mycoplasma hominis and 2 belonged to Mycoplasma genitalium.
Conclusions: This study showed the presence of Mycoplasma in athletes were less than non-athletes. In addition PCR was a sensitive and precise method to identify Mycoplasma genus and species
Detection of blaPSE and blaTEM genes encoding B-Lactamase in clinical samples of Salmonella typhimurium by Multiplex PCR
Background and Aim: B-Lactam antibiotics are widely used in the treatment of salmonellosis. Alarming reports have pointed out the rapid development of resistance to these agents, involving Salmonella serovars such as Enteritidis, Typhimurium, Panama, and Typhi in several countries. The aim of this study was to investigate the antibiotic resistance profiles and the prevalence of blaPSE and blaTEM genes among Salmonella typhimurium in humans in Tehran.
Materials and Methods: All 46 isolates were detected from a collection of human sampels in veterinary faculty, Islamic Azad University. Samples were tested to resist to ampicillin, chloramphenicol, tetracycline, cephalothin, ceftriaxone, ceftazidime, amoxicillin-clavulanate, gentamicin, trimethoprim-sulfamethoxazole and amikacin. Isolates examined by Polymerase chain reaction analysis to detect the presence of the blaPSE and blaTEM resistance genes.
Results  and Conclusions: Results of antibiogram showed (82.6%) resistance to ampicillin, (80.4%) to chloramphenicol, (69.5%) to tetracycline, (80.4%) to cephalothin, (56.5%) to amoxicillin-clavulanate and (43.4%) to trimethoprim-sulfamethoxazole. Among 46 Salmonella isolates, 43 (93.4%) showed resistance to two or more antibiotic families. blaTEM gene were identified in 1 (2.1%) Salmonella isolates. All the isolates were negative for blaPSE gene. Salmonella strains among humans were resistant to ampicillin, cephalothin, chloramphenicol, tetracycline, amoxicillin-clavulanic acid and trimethoprim-sulfamethoxazole.The identification of ESBL genes in Salmonella and MDR Multi Drug Resistance (93.4%) has considerable implications for public health. Carrying two or more beta-lactamase resistance gene is very worring, because certain combinations of genes could effectively limit all β-lactam therapeutic options. Besides, ESBL producing bacteria are typically associated with multidrug resistanc