High prevalence of SCC mec-associated Phenol-soluble modulin gene in clinical isolates of methicillin-resistant. Staphylococcus aureus

INTRODUCTION

We aimed to determine the distribution of Phenol-soluble modulin-mec (psm-mec) gene and its relationship with biofilm formation in clinical methicillin-resistant S. aureus (MRSA).

METHODS

In a descriptive study, a total of 94 cefoxitin-resistant S. aureus isolates were collected from patients and tested for antibiotic susceptibility testing, multiplex polymerase chain reaction (MPCR) for detection of mecA and pvl genes, PCR for detection of psm-mec gene and SCCmec typing of psm-mec and pvl-positive isolates. Furthermore, isolates were tested by microtiter plate method for biofilm formation assay.

RESULTS

Multiplex PCR for detection of mecA and pvl genes was performed for all cefoxitin-resistant isolates. The mecA gene was found in 92 (97.9%) isolates but none of the isolates carried the pvl gene. Sixty-five (69.1%) isolates harbored psm-mec genes and 95.4% of these isolates belong to SCCmec type III. Statistical analysis showed a significant difference between the presence or absence of psm-mec gene and biofilm production (P<0.001).

CONCLUSION

In this study, more than half of the MRSA strains harbored psm-mec gene and almost one-fifth of them produced strong biofilm. Since the strains with strong biofilm formation have more antibiotic resistance and cause the long-lasting infection, for the suitable treatment of hospitalized patients with this kind of MRSA strains, we should be paid more attention to these strains.

New insight to IL-23/IL-17 axis in Iranian infected adult patients with gastritis: effects of genes polymorphisms on expression of cytokines

BACKGROUND AND OBJECTIVE

Chronic inflammation is the hallmark of the pathogenesis of H. pylori-induced gastric cancer. IL-17A and IL-17F are inflammatory cytokines expressed by a novel subset of CD4+Th cells and play critical function in inflammation. We evaluated the relationship between IL-17A G197A, IL-17F A7488G and IL23R+2199 A/C polymorphisms with IL-6, IL-17, IL-21, IL-23 and TGF-β1 mRNAs expression in regard to H. pylori infection with chronic gastritis.

MATERIAL AND METHODS

Total RNA and genomic DNA were extracted from gastric biopsies of 58 H. pylori-infected patient with gastritis. Afterward, mucosal IL-6, IL-17, IL-21, IL-23 and TGF-β1 mRNAs expression and polymorphisms in IL-17A G197A, IL-17F A7488G and IL-23R +2199A/Cin gastric biopsies were determined by real-time PCR and PCR-RFLP.

RESULTS

Our results show that IL-17A G197A, IL-17F A7488G andIL23R +2199A/C polymorphisms have no effect on mucosal expression of IL-6, IL-17, IL-21 and TGF-β1 mRNAs expression in H. pylori-infected patients with chronic gastritis.

CONCLUSIONS

These results suggest that IL-17A G197A, IL-17F A7488G and IL23R +2199A/C polymorphisms no alter mucosal cytokine pattern in Iranian patients with H. pylori-associated gastritis diseases.

Accuracy of dipstick urinalysis as a screening method for detection of glucose, protein, nitrites and blood

This study determined the reliability of dipstick urinalysis for detection of protein, glucose, blood and nitrites in non-random urine samples from 300 people aged > 50 years attending a health centre for check-up. The gold standards were fasting blood glucose for glucosuria and the sulfosalicylic acid method for urine protein. Microscopic examination of urinary sediment and urine culture were also performed for positive dipstick results for haematuria and nitrites. The sensitivity, specificity and positive and negative predictive values of the dipstick test for detection of protein were 80.0%, 95.0%, 22.2% and 99.6% and for glucose were 100%, 98.5%, 87.0% and 100% respectively. Dipstick urinalysis can be a reliable screening method for diagnosis of urinary tract infection and diabetes mellitus but not for proteinuria.