No abstract

Diabetic hyperglycemia is associated with increased production of reactive oxygen species (ROS). ROS reacts with DNA resulting in various products, such as 8-hydroxydeoxyguanosine (8-OHdG), that excrete in urine owing to DNA repair processes. Urinary 8-OHdG has been proposed as an indicator of oxidative damage to DNA. This study aimed to evaluate relationship between oxidative damage to DNA and protein glycation in patients with Type 1 diabetes. We measured urinary 8-OHdG level in diabetic patients and healthy subjects and discussed its relationship to glycated hemoglobin (HbA(1c)) and glycated serum protein (GSP) levels. Furthermore plasma malondialdehyde (MDA) level monitored as an important indicator of lipid peroxidation in diabetes. We studied 32 patients with Type 1 diabetes mellitus and compared the measured factors with those of 48 age-matched nondiabetic controls. GSP and MDA were measured bycolorimetric assay. Urinary 8-OHdG measurement was carried out using ELISA. In this study urinary 8-OHdG, HbA(1c), plasma MDA, and GSP levels were progressively higher in diabetics than in control subjects (P<0.05). Furthermore we found significant correlation between urinary 8-OHdG and HbA(1c) (P<0.05) in diabetic group. Correlation between fasting blood sugar and GSP were significant. We also found significant correlation between fasting blood sugar and MDA. This case-control study in young diabetic patients showed increased blood glucose and related metabolic disorders result in oxidative stress and oxidative damage to DNA and lipids. Furthermore oxidative damage to DNA is associated to glycemic control level, whereas lipid peroxidation level was not significantly correlated with glycemic control level. J. Clin. Lab. Anal. 24:72-76, 2010. (c) 2010 Wiley-Liss, Inc.

Background: Methicillin -resistant staphylococcus aureus (MRSA) is associated with serious infections. Having the ability of biofilmformation decrease their susceptibility to antibiotics. Objectives: The aim of this study was to determine the prevalence of biofilm formation among MRSA isolated from nasal carriers in the Beheshti Teaching Hospital in Kashan, Iran. Materials and Methods: A cross-sectional study was conducted in 810 patients referred to emergency department in Beheshti Hospital in Kashan. Sterilized nasal swabs were used for collecting nasal bacteria. Nasal specimens were further recognized as S. aureus strains by standard biochemical tests, and MRSA isolates were detected by disk diffusion method. PCR assay was used for detecting mecA gene in MRSA isolates. The susceptibility of MRSA isolates to amikacin, clindamycin, gentamicin, ciprofloxacin, SXT, erythromycin, tetracycline were determined by using disk diffusion method according to recommendation of CLSI. Biofilm formation ability of MRSA isolates were examined by crystal violet microtitre plate assay and Congo red agar (CRA). Results: Two hundred and ninety six (36.5%) out of 810 isolates were S. aureus. Twenty six (8.8%) of all S. aureus isolates were recognized as MRSA. All the MRSA isolates have the ability of biofilm formation which 15.4%, 19.2% and 65.4% of them were strong, medium and weak biofilm producer respectively. The resistance rate of strong biofilm producer were; erythromycin (100%), clindamycin (75%), ciprofloxacin (75%), SXT (75%), gentamycin (50%), tetracycline (0%), amikacin (0%). Conclusions: High rate of MRSA nasal carrier and having the ability of biofilm formation which decrease their susceptibility to antibiotics, is an alarming for public health. Statistically significant correlation between susceptibility to tetracycline and MRSA carrier was observed.

Objectives: We investigated the potential relationships between biofilm formation and prevalence of virulence genes (asa1, esp, cylA, and gelE/sprE), and antimicrobial resistance genes (aac (6’)/aph (2”) in Enterococcus faecalis isolated from patients with urinary tract infection.Patients and Methods: In this survey 95 E. faecalis isolates from patients with urinary tract infections staying at Shahid Beheshti hospital in Kashan, Iran, between 2007 and 2008 were studied. We analyzed the prevalence of genes encoding virulence factors (asa1, esp, cylA and gelE/ sprE), and antimicrobial resistance genes [(aac (6’)/aph (2”)] by PCR. In addition, the production of biofilm and extracellular enzymes, hemolysin (Hln) and Gelatinase were examined.Results: The asa1,(aac (6’)/aph (2”), esp, cylA, and gelE/sprE were detected in 94.7%, 68.4%, 61.1%, 50.5% and 21.1% of E. faecalis isolates, respectively. The hemolysin production and gelatinase activity were seen in 44.2% and 20% of isolates, respectively. 16.8% of E. faecalis isolates showed strong and 83.2% exhibited weak biofilm formation. The percentages of genes encoding virulence factors in E. faecalis which had the ability of strong biofilm formation were as follows: gelE/sprE 25%, esp22.4%, (aac (6’)/aph (2”) 18.5%, asa1 16.7% and cylA 14.6%. The presence of both aac (6’)/aph (2”) and esp positive act as a risk factor for biofilm formation (P value < 0.001).Conclusions: There was a significant relationship between biofilm formation and possession of esp and aac (6’)/aph (2”) genes. There was no evidence between biofilm formation and presence of any other gene. Enterococcal infections associated with biofilm formation have been a serious problem in recent years

No abstract

Background:Escherichia coli is an important bacterial species based on incidence and associated infection severity. Some E. coli strains produce extended-spectrum beta lactamase (ESBL) and are called ESBL-producing E. coli. These strains are resistant to most classes of cephalosporin and a number of other classes of antibiotics. Plasmids carrying qnr genes have been found to transmit quinolone resistance.Objectives:The aim of this study was to determine the frequency of qnr genes in ESBL-producing and non-ESBL-producing E. coli isolated from outpatient and hospitalized patient clinical specimens from Imam Reza hospital in Mashhad, Iran.Materials and Methods:Two hundred E. coli strains, isolated from different clinical specimens were used. ESBL-producing E. coli were detected by determining susceptibility to ceftazidime, cefotaxime, and cefpodoxime with the phenotypic confirmatory test (PCT). PCR analysis was employed to detect the qnrA, qnrB, qnrS, blaTEM, and blaSHV genes.Results:Eighty-six (43%) isolates were ciprofloxacin-resistant. The PCT identified 85 (42.5%) of 200 E. coli isolates as ESBL-producing. The blaTEM, blaSHV, qnrA, qnrB, and qnrS gene were found in 65 (76.47%), 23 (27%), 63 (31%), 34 (17%), and 14 (7%) isolates, respectively.Conclusions:The high prevalence of quinolone resistance genes, which indicates antibiotic resistance, in the Imam Reza Hospital of Mashhad is a major concern. Hence, the antibiotics prescription policy should be revised, and infection control measures should be improved.

No abstract

Article Subject: Molecular Microbiology DOI: Background and Aims: Listeria monocytogenes, a gram positive, facultative, intracellular bacterium is the causative agent of listeriosis that is transmitted to human through raw and ready-to-eat foods. The aim of the present study was to determine dominant serovars of L. monocytogenes isolated from spontaneous abortion using phenotypic and genotypic methods. Materials and Methods: In present study, 258 clinical specimens including placental secretions, vaginal swabs and blood samples from 123 patients with abortion were selected in sterile condition then bacteriological, serological and molecular tests were conducted; dominant serotypes were identified by Multiplex PCR. Results: Out of 28 (%18.8) isolates of L. monocytogenes 21 (%17.7), 5 (%5.7) and 2 (%3.37) were isolated from placental secretions, vaginal swabs and blood respectively. Maximum and minimum isolated of bacteria related to placental secretions and vaginal swabs with 21 and 2 isolates respectively, of which 14 (%50) 1/2a, 10 (%35.7) 4b and 4 (%14.6) 2c serovars were reported for the first time. All of serovars played a key role in the spontaneous abortion as dominant and common serotypes in Iran. All of the isolates 28 (%22.76) showed hlyA gene and 24 isolates (%19.57) were positive for iap gene and compaired with control group there was significant different between the two groups (P<0.0002). Conclusion: The present study showed the isolation dominant and common serotypes of L. monocytogenes from spontaneous abortion and demonstrated that the presence of hlyA and iap were effective genes in increasing aggressive and pathogenicity. Serotypes that lacked the iap gene have less pathogenicity and influenced the pathogenesis in mice. It was also concluded that in the absence of access to molecular tests, performing PI-PLC, Congored and in vivo pathogenicity can be effective in detecting pathogenic serotypes from non-pathogenic L. monocytogenes.