فهرست مطالب صدیقه نعمت الهی

Multidrug resistance is emerging among gram negative bacteria that cause hospital infections or community acquired around the world. The aims of this study were (1) determination of antibiotic susceptibility profile of Enterobacter spp. isolates recovered from blood, (2) phenotypic identification of ESBL and AmpC-producing isolates, (3) identify MDR strains, and (4) identification isolates harboring blaSHV gene using PCR method.
In this cross-sectional study, 90 isolates of Enterobacter spp. isolated from blood stream infection from patients admitted to hospitals in Shiraz using BACTEC 9240 automated system during 10 years (2004-2014). The isolates again were identified by using embedded biochemical tests in the Enterobacteriaceae API-20E diagnostic system. According to proposed protocol by CLSI (2014), standard disc diffusion method and DDST phenotypic test were used for antibiotic susceptibility test, and identification of ESBL-producing strains, respectively. PCR molecular method was used to identify blaSHV gene in strains.
In this study, as observed, meropenem (98.9%), imipenem (95.6%) and colistin (93.3%) were the most effective antibiotics against isolates. Isolates showed the best response to ceftazidime (47.8%) and ceftriaxone (42.2%), respectively, among the third generation of cephalosporins which were investigated. Results showed that 11.1% of isolates were MDR. 15.5% isolates were positive ESBL and positive AmpC, simultaneously. As revealed, 11.1% of isolates were MDR. The results of PCR to search for blaSHV gene in Enterobacter isolates revealed that 7.8% of the strains harboring this gene.
Results showed that the resistance of Enterobacter isolates to the third generation of cephalosporins has become a national health-threatening problem. Epidemiologic studies are crucial in order to presentation of comprehensive national program to preventing emergence and dissemination of resistant bacteria in the country. We believe that carbapenems should be used for the treatment of strains resistant to other antibiotics in order to preservation of carbapenems as strategies for the treatment of Enterobacter spp.

Protamine deficiency and DNA fragmentation have a profound effect on embryo gene expression. Incubation of sperm in culture medium leads to morphological changes of the nucleus and DNA release. However, the relationship between protamine deficiency and DNA fragments released from incubated sperm and the presence of the DNMT1 gene is not known. Semen analysis was performed according to the WHO criteria. CMA3 staining was used to determine protamine deficiency. Twenty million sperms per sample were incubated in Ham’s F10 medium for 24 hr at 37 °C. After centrifugation, DNA was extracted from the supernatant. DNA concentration was measured by biophotometer. The presence of the DNMT1 gene was confirmed by PCR using specific primers and agarose gel electrophoresis.A significant correlation was observed between the DNA fragments released from sperm in culture media and CMA3 staining (P<0.05). The presence of DNMT1 gene was significantly correlated with DNA fragments released from the sperm (P<0.05). Protamine deficiency and the presence of DNMT1 gene were not significantly correlated.These results demonstrate that incubation of protamines-deficient sperm leads to the release of additional DNA fragments that eventually could have detrimental effectson embryo’s health.