Objectives: Pseudomonas aeruginosa is known as a leading cause of nosocomial infections worldwide. Antimicrobial resistance and biofilm production, as two main virulence factors of P. aeruginosa, are responsible for the persistence of prolonged infections. In this study, antimicrobial susceptibility pattern and phenotypic and genotypic characteristics of biofilm of P. aeruginosa were investigated. Results: A total of 80 clinical P. aeruginosa isolates were obtained. Isolates showed resistance to all antibiotics with a rate from 12.5% (n = 10) against amikacin and piperacillin/tazobactam to 23.75% (n = 19) to levofloxacin. Multidrugresistant P. aeruginosa accounted for 20% (n = 16). 83.75% (n = 67) of isolates showed biofilm phenotype. All three biofilm-related genes were found simultaneously in 87.5% (n = 70) of P. aeruginosa and 13.5% (n = 10) of the isolates had none of the genes tested. From the results of the present study, combination therapy including an anti-pseudomonal beta-lactam (piperacillin/tazobactam or ceftazidime) and an aminoglycoside or carbapenems (imipenem, meropenem) with fluoroquinolones in conjunction with an aminoglycoside can be used against Pseudomonas infections. However, reasonable antimicrobial use and high standards of infection prevention and control are essential to prevent further development of antimicrobial resistance. Combination strategies based on the proper anti-pseudomonal antibiotics along with anti-biofilm agents can also be selected to eradicate biofilm-associated infections.

Retroperitoneal surgical resection margin involvement by caecal and ascending colon carcinoma is a marker of advanced tumour stage and associated with a high incidence of synchronous and metachronous distant metastasis. More aggressive surgery to obtain a clear margin or postoperative radiotherapy to the tumour bed is likely to benefit only a minority of patients.

Background Biofilms are a main pathogenicity feature of Pseudomonas aeruginosa and has a significant role in antibiotic resistance and persistent infections in humans. We investigated the in vitro activities of antibiotic ceftazidime and enzyme cellulase, either alone or in combination against biofilms of P. aeruginosa. Results Both ceftazidime and cellulase significantly decreased biofilm formation in all strains in a dose-dependent manner. Combination of enzyme at concentrations of 1.25, 2.5, 5, and 10 U/mL tested with 1/16× MIC of antibiotic led to a significant reduction in biofilm biomass. Cellulase showed a significant detachment effect on biofilms at three concentrations of 10 U/mL, 5 U/mL, and 2.5 U/mL. The MIC, MBC, and MBEC values of ceftazidime were 2 to 4 µg/mL, 4 to 8 µg/mL, and 2048 to 8192 µg/mL. When combined with cellulase, the MBECs of antibiotic showed a significant decrease from 32- to 128-fold. Conclusions Combination of the ceftazidime and the cellulase had significant anti-biofilm effects, including inhibition of biofilm formation and biofilm eradication in P. aeruginosa. These data suggest that glycoside hydrolase therapy as a novel strategy has the potential to enhance the efficacy of antibiotics and helps to resolve biofilm-associated wound infections caused by this pathogen.

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Article Subject:Medical Microbiology Background and Aims: Helicobacter pylori is the main cause of various gastroduodenal diseases. It is estimated that app roximately, more than half of the adult population in developed countries and 90% of people in developing countries infected with H. pylori. H. pylori infection may be related to Genetic of virulence factors and environmental factors. The aim of this study was to assess of frequency cagA and vacA genes of H. pylori isolated from patients with Gastrointestinal Disorders.Materials and Methods: This cross-sectional descriptive study carried out on 120 patients with gastrointestinal diseases in Gorgan city in 2017. (40 patients of gastric cancer, 40 patients of peptic ulcer, 40 patients of without cancer and ulcer). After genomic DNA extraction PCR was carried out using specific H.pylori primers.Results: Overall, 120 H.pylori strains were isolated. The frequency of cagA was %67.5 in gastric cancer, %60 in peptic ulcer and %45 in patiens without ulcer and gastric cancer. Also frequency of vacA gene was detected %55 in gastric cancer, %40 in peptic ulcer and %27.5 in patiens without ulcer and gastric cancer.Conclusion: Based on our findings it seems that the cag A and vac A genes were virulence among H. pylori isolated from studied patients. The frequency of cagA and vacA genes H. pylori were than in gastric cancer and peptic ulcer patients.

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Introduction: Toll-like receptors (TLRs), especially TLR2, play an important role in the immune responses of patients with tuberculosis (TB). The prevalence of TB is estimated 38.15 per 100,000 population in Golestan Province, Iran, which is higher than the rates reported in other provinces. Objectives: The current study aimed at detecting Arg677Trp and Arg753Gln polymorphisms in TLR2 genes detected in patients with TB in Golestan province. Methods: A total of 130 blood samples were collected from patients with sputum smear-positive TB, and 130 blood samples were collected from healthy individuals. Two polymorphisms of TLR2 gene, i e, Arg677Trp and Arg753Gln, were investigated via polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) and sequencing methods. Results: History of corticosteroid use was more frequently reported in patients, compared to the controls, while the frequency of Bacillus calmette-guerin (BCG) vaccination was more reported in controls. PCR-SSCP analysis of the TLR2 Arg677Trp region showed an almost identical pattern for patients and controls, while 2 SSCP patterns were observed in the amplicon, related to the Arg753Gln polymorphism. DNA sequencing for the Arg677Trp polymorphism showed a duplicated pseudogene, similar to the mutant sequence (C > T), as this polymorphism cannot be considered conclusive. The Arg753Gln polymorphism was not found in the samples, although nucleotide deletion (G) was detected at position 808 among the patients. Conclusions: The Arg753Gln polymorphism was not involved in susceptibility to TB in the current study population. The presence of pseudogenes in some genes such as TLR2 necessitates careful interpretation of such studies.