seyed abdolmajid khosravani

Humans can develop both acute and chronic infections from Pseudomonas aeruginosa , a bacterium that is a prominent cause of nosocomial infections, as well as respiratory, urinary tract, burn, wound, ear, eye, and bloodstream infections.

This study aimed to identify antibiotic resistance in P. aeruginosa strains obtained from hospitalized patients and assess the frequency of virulence genes.

In this cross-sectional study, 86 strains of P. aeruginosa were isolated from patients in various hospital wards in Shiraz and Yasuj in 2021. Antibiotic susceptibility was tested using the disk diffusion method, while the frequency of virulence genes ( aprA , phzM , phzS ) and antibiotic resistance genes ( blaGES , blaSPM , blaVIM ) was evaluated using PCR and specific primers.

The P. aeruginosa isolates showed the highest antibiotic resistance to imipenem and the lowest resistance to piperacillin-tazobactam. PCR amplification of aprA , phzM , and phzS genes indicated that aprA had the highest frequency among the isolates, with a prevalence of 98.8%. The frequencies of phzM and phzS were 96.5% and 91.9%, respectively.

This study revealed a high prevalence of the virulence genes aprA , phzM , and phzS in P. aeruginosa isolates. Given the bacterium’s resistance to many antibiotics, clinicians should exercise caution when prescribing antibiotics, particularly for infections caused by P. aeruginosa .

Pseudomonas aeruginosa is a Gram negative ubiquitous opportunistic organism and one of the more problematic drug-resistant pathogens encountered today.
The aims of the current multicenter research were to assess antibiotic resistance profiles, carbapenemase production, and detection of antibiotic resistance IMP gene as well as virulence factors genes including exoA, algD, lasB, and plcH among the clinical isolates of P. aeruginosa.
A total of 80 nonduplicate isolates of P. aeruginosa were recovered from inpatients. Bacterial identification was done by standard diagnostic tests. Species was confirmed by detection of the exoA gene using the PCR technique. Antimicrobial susceptibility test was performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Carbapenemase production among the isolates was determined by the modified Hodge test. Virulence genes were detected by PCR.
A total of 42 (52.5%) isolates recovered from wound specimens. Colistin was the most effective antibiotic against isolates (97.5% isolates were susceptible) and levofloxacin was the least effective drug (67.5% isolates were resistant). The most common antibiotic resistance pattern was CIPR-CPMR-GEMR (47 isolates). In total, 47 (58.75%) isolates were identified as multidrug resistance (MDR), while 30% of isolates were carbapenemase producer (MHT). Among studied isolates, plcH and lasB genotypes (100% isolates) were the most common virulence gene patterns. Of 80 P. aeruginosa isolates, 39 (48.75%) showed algD, plcH, lasB, and IMP genotype. The blaIMP resistance gene was detected in all MHT positive and MDR isolates.
In our study, the emergence of potentially highly pathogenic and carbapenem-resistant strains in joining with a MDR phenotype is alarming, as a feasible outcome would be a severe clinical result concomitant with critical restrictions in antibiotic therapy.

The antibiotic resistance of bacteria has increased in the last decade. The mecA gene plays an important role in the pathogenicity of Methicillin-Resistant Staphylococcus aureus (MRSA) by increasing antibiotics resistance. Recent studies have indicated that nanotechnology, as an antimicrobial agent, has had promising results.
The present study was conducted to determine the effect of Cu-BPDCA-Ty on antibacterial activity and mecA gene expression in clinical and standard strains of MRSA.
The phenotypic tests were used to identify MRSA strain and confirmed with molecular detection of mecA gene. Synthesized Cu-BPDCA-Ty was confirmed with different techniques such as XRD and SEM analysis. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) were determined by the micro broth dilution method. Real time PCR was used to investigate gene expression. Pta gene was considered as an endogenous control for normalization. Data were analyzed using one sample t test and paired t test in the SPSS software Version 22.
The findings indicated that the MIC and the MBC of Cu-BPDCA-Ty against the standard and clinical strains of MRSA were 0.5 mg/mL, 0.8 mg/mL, 0.46 ± 0.08 mg/mL, and 0.7 ± 0.1 mg/mL, respectively. Analysis of the real- time PCR indicated that all treated groups with Cu-BPDCA- Ty showed a significant decrease in the expression of the mecA gene compared to the control group (P Cu-BPDCA-Ty had an antibacterial effect on MRSA and induced downregulation of expression of the mecA gene.

Most urinary tract infections (UTI) are caused by Escherichia coli. Integrons have an important role in distributing antibiotic resistance genes among bacteria.. The aim of this study was to investigate the presence of class 1, 2 and 3 integrons and their association with antibiotic resistance in E. coli isolated from patient with UTI in Yasuj, Iran..Patients and In this cross-sectional study a total of 200 E. coli were collected from 1820 patients diagnosed with UTI that had been referred to two clinical laboratories between February 2013 and November 2014 in Yasuj city, southwest of Iran. Susceptibility of isolates to 11 different antibiotics was determined by the disk agar diffusion method. multiplex-polymerase chain reaction (PCR) was used for detection of class 1, 2 and 3 integrons. The data were analyzed using the SPSS software (version 16) and the chi-square test. A P value of < 0.05 was considered statistically significant.. The highest rate of resistance was observed toward cephalothin (99%) and amoxicillin (76%) while only two (1%) isolates showed resistance to imipenem. Overall, 79% of isolates were multi drug resistant (MDR). Class 1 and 2 integrons were detected in 104 (52%) and 5 (2.5%) isolates respectively, while none of the isolates were positive for class 3 integrons. A significant association was observed between the presence of integrons and resistance to co-trimoxazole, nalidixic acid, ciprofloxacin, amoxicillin, ceftazidime and tetracycline (P < 0.05).. High MDR isolates of E. coli were observed in this study. The significant association between class 1 integrons and resistance to ciprofloxacin, nalidixic acid, co-trimoxazole, amoxicillin, ceftazidime and tetracycline showed that class 1 integrons have an important role in resistance to these antibiotics in this region..

Adenylate cyclase toxin (CyaA) is an important virulence factor of Bordetella pertussis, the causative agent of whooping cough, and a potential component of acellular pertussis vaccine.. In the present study the impact of invasive CyaA on oxidative activities of phagocytes was compared with the other form of this molecule to investigate the activity of different parts of molecules on leukocytes.. The work involved the production of two purified forms of CyaA with different enzymic and invasive properties. They were: the native enzymatically-active, invasive toxin (CyaA), an invasive derivative lacking AC enzymic activity (CyaA*). Different concentrations of CyaA and CyaA* were used to investigate dose-dependent effects of the toxins on oxidative burst in U937 human monoblastic cells, J774.2 mouse macrophage-like cells and fresh human granulocyte cells by Burst Test assay.. Significant effects were observed with 0.2 µg protein/ml of CyaA. For instance, there was almost complete (80%) inhibition of phagocytosis by J774.2 cells and 70% inhibition of phagocotosis by human granulocyte cells. The results showed that production of the oxidative burst was significantly impaired by increasing concentrations of CyaA compared to cells treated with PBS. However, there was no significant effect with CyaA* on either cells.. The results of the study showed that both enzymatic and invasive functions were required for the oxidative burst effects of adenylate cyclase toxin in leukocytes..

Background and Crimean-Congo hemorrhagic fever is a zoonotic disease that has been reported from different parts of Iran. The aim of this study was to investigate the Seroepidemiology of Crimean-Congo hemorrhagic fever in high risk professions in Yasuj، Iran. The present study included 108 subjects at risk; 34 butchers، 20 slaughters، 14 slaughter-house workers، 20 waiters، and 20 housewives were randomly selected. After completing the demographic characteristics and history of febrile diseases، blood samples were obtained and specific IgG antibodies against Crimean-Congo hemorrhagic fever virus were tested. The collected data were analyzed with descriptive statistics and percentages and chi-square tests. Of the 108 subjects، 5 (4. 6 percent) with positive serology were among restaurant the workers 2 (10 percent) and slaughterers 3 (15 percent)، respectively، which was statistically significant. There were no positive serologies in the other groups. The present study showed that the Seroepidemiology of Crimean-Congo hemorrhagic fever in high risk professions is not highly prevalent in Yasuj، Iran. However، the need for further surveillance and prevention programs is still recommended.