Prevalence of Vancomycin Resistance in Methicillin-Resistant Staphylococcus Aureus

Abstract: Background & Aims: Staphylococcus aureus is one of the most common pathogens in nosocomial infections. Vancomycin is the most important therapeutic drug of choice for treatment of infections caused by methicillin-resistant Staphylococcus aureus (MRSA) strains. Therefore, vancomycin-resistant Staphylococcus aureus (VRSA) or vancomycin-intermediate Staphylococcus aureus (VISA) strains are warnings for the medical community. The aim of this study was to evaluate the prevalence of vancomycin resistance in methicillin-resistant Staphylococcus aureus isolated from the nose of patients hospitalized in Imam Reza Hospital, Kermanshah, Iran. Methods: In the present study, 85 strains of methicillin-resistant Staphylococcus aureus were isolated from patients in Imam Reza Hospital and evaluated for vancomycin resistance with microdilution test, Epsilometer test (E-test), and polymerase chain reaction (PCR). Results: None of the strains were completely resistant to vancomycin; however, 39 strains (45.9%) were diagnosed as hetero-VRSA (hVISA) strains. Conclusion: VISA and VRSA strains were not observed in this study which is a promising finding in the treatment of clinical infections due to Staphylococcus aureus in our society. However, in our study, the prevalence of hVISA strain was 45.9%, which is perhaps a sign of the appearance of more resistant strains (VISA and VRSA) in our country in the future. Keywords: Staphylococcus aureus, Vancomycin, Nose, Methicillin, Hetero-vancomycin-intermediate Staphylococcus aureus (hVISA

Relationship of venous blood gas with cervical esophagogastric anastomotic leak

Objective: this study investigated the relationship between various parameters of venous blood gas analysis of gastric fundus veins and cervical esophagogastric anastomotic leaks after transhiatal esophagectomy. Background: decreased tissue perfusion is one of the causes of anastomotic leak. There are various methods used to assess gastric conduit perfusion, with different results, and we lack a reliable method. Method: this descriptive study, performed from March 2008 to October 2010, consisted of 45 patients with esophageal cancer who underwent transhiatal esophagectomy. After gastrolysis, blood samples were taken from a gastric fundus vein and submitted for venous blood gas analysis. The cervical wounds were examined 5 days postoperatively. The patients were divided into 2 groups based on the presence of leakage, and mean values of the venous blood gas analysis were compared. Results: we observed significant differences in mean pH, PCO2, and O2 saturation between the 2 groups (p = 0.04, p = 0.03, and p = 0.04, respectively). Conclusion: venous blood gas analysis of gastric fundus veins appears to be a feasible and fast method for intraoperative assessment of microperfusion in the gastric fundus. © The Author(s) 2012

Genotyping of ESBL Producing Uropathogenic Escherichia coli

Background and Objective. Urinary tract infection (UTI) is one of the most common bacterial infections in the world. Molecular fingerprinting of UTI isolates such as pulsed-Field Gel Electrophoresis using for Clonal distribution and determine of predominant type. The aim of the study was to determine genotyping of ESBL producing UPECs. Material and Methods. 200 UPEC isolates from outpatients with UTI were obtained. Antimicrobial susceptibility and interpretation were performed by disk diffusion. Virulence factors for UPECs were screened by using PCR. UPECs were analyzed by Pulsed-Field Gel Electrophoresis and images analyzed by Phoretix1DPro software. Results. A total of 200 isolates of UPECs, 24.5% (n=49) of isolates, were positive for ESBL production. Resistance ranged from 0% for amikacin and imipenem to over 93.9% for carbenicillin and ampicillin. Frequencies of haemagglutination, haemolysin, and hydrophobicity were 51%, 18.3%, and 14.28%, respectively. A total of 10 different genotypes were obtained, which include nine common clones and one single clone. Conclusion. We confirmed the prevalence of virulence phenotyping especially Haemagglutination among UPEC strains and that it can also contribute to virulence in these strains. Large diversity in genotypes was observed in the isolates that could be indicative of different sources of infection in community acquired

Mechanical properties of multi-walled carbon nanotube/epoxy composites

Untreated and acid-treated multi-walled carbon nanotubes (MWNT) were used to fabricate MWNT/epoxy composite samples by sonication technique. The effect of MWNT addition and their surface modification on the mechanical properties were investigated. Modified Halpin-Tasi equation was used to evaluate the Young's modulus and tensile strength of the MWNT/epoxy composite samples by the incorporation of an orientation as well as an exponential shape factor in the equation. There was a good correlation between the experimentally obtained Young's modulus and tensile strength values and the modified Halpin-Tsai theory. The fracture surfaces of MWNT/epoxy composite samples were analyzed by scanning electron microscope

2003年バム地震におけるバム市内の地盤と基礎構造の挙動

Following the devastating earthquake disaster in Bam city, Iran, a reconnaissance team was sent to the site. The authors participated in its activities with special emphasis on geotechnical issues. A soil investigation in the city revealed that local soils have su$ciently good properties and cannot be the main source of heavy damage to houses. Because bridges and structures other than buildings experienced minor damage during the same earthquake, it seems that the structural weakness of houses made of masonry and adobe is a major problem. A possible mitigating measure may be to use light materials such as ESP, although consideration has to be given to the local climate and the landscape

Genomic diversity and antimicrobial susceptibility profiling of nasal carriage Staphylococcus aureus isolated from pediatric ward in Western Iran

Nasal carriage of Staphylococcus aureus (S. aureus) probably causes the transmission of infection between individuals in hospital and community. This study aimed to evaluate the molecular epidemiology and antibiotic resistance pattern of nasal carriage S. aureus in pediatric ward patients and personnel. A total of 122 Nasal samples were taken from 28 personnel and 94 hospitalized patients in the pediatric ward. Minimum Inhibitory Concentration (MIC) to vancomycin and cefoxitin was determined by Agar dilution method strips. All S. aureus isolates were analyzed by pulsed-field gel electrophoresis (PFGE). A total of 41 S. aureus were isolated from the patients. 16 isolates (39.09%) were hospital-associated S. aureus (HA-SA) and 25 (60.97%) were community-associated S. aureus (CA-SA); also, 13 S. aureus isolates were obtained from the personnel. Based on MIC results, all of S. aureus isolates were susceptible to vancomycin, and in 41 patient isolates, 13 isolates (31.7%) were resistant to cefoxitin (MRSA). Of 13 S. aureus isolates of the personnel, 3 (23%) isolates were MRSA. Totally 11 common clones and 13 single clones were obtained. In conclusion the prevalence of CA-SA in the ward was higher than that of HA-SA. In the strains obtained from a hospital ward, there was a high epidemiology, genotypic diversity in the studied ward. However, horizontal transfer of S. aureus was observed between patients and between personnel and patients, which indicated the risk of transmission of resistant strains in the hospital wards. Keywords: Staphylococcus aureus, Nasal carriage, Pediatric ward, Antimicrobial susceptibility, Pulsed-field gel electrophoresi

Antibiotic resistance in uropathogenic Escherichia coli isolated from urinary tract infections out-patients in Kermanshah

Background: Urinary tract infections (UTIs) are common cause of infections described in out-patient's setting and increase in antibiotic resistance of Escherichia coli, is encountered world-wide. Antibiotic treatment is usually empirical; therefore, this study to provide the knowledge of local resistance pathogen patterns in Kermanshah. Materials and Methods: We conducted a retrospective analysis of all E. coli isolates from urine samples admitted to Kermanshah Central lab between March 2011 and 2012 were included. Antimicrobial resistance was tested by the Kirby-Bauer disk diffusion. Results: This study showed a total of 20,742 samples, 1228 (5.92) were positive for pathogenic bacteria. E. coli were the predominant 801 isolate (65.2%). Out of the 13 antibiotics tested for E. coli isolates, minimum and maximum resistance were observed to ampicillin (9.4%) and augmentin (68.6%). Almost 59-66% of the uropathogenic E. coli strains were resistant to amikacin, co-trimoxazole, tetracycline and cephalotin and nearly half of them were resistant to nalidixic acid and cephalexin. Conclusion: This study confirms that E. coli is still the most common uropathogen isolated. Augmentin and amikacin are not as a first choice for treatment of UTI in Kermanshah area. Ampicillin and nitrofurantoin may be considered as a first choice empiric agent in out-patients

The Impact of Oil Price Shocks on Growth and Inflation of OPEC Countries with an Emphasis on OPEC Political Risk Shocks

Considering the source of oil shocks, this study aims to investigate the effect of oil price shocks on the key macroeconomic variables of the OPEC countries. Even though oil shocks are originated by various factors, political risks are of great importance. Using structural vector-autoregressive model, we disentangled oil shocks and studied their impacts on OPEC’s GDP growth and inflation, using a Panel-VAR for 1994:1-2016:4. Our results highlight that among oil shocks, the oil price shocks stemming from the political risk of OPEC countries have the most significant impact on the OPEC's economic growth, while not having any significant impact on inflation of the countries. We also learned that oil supply shocks could also boost economic growth and increase inflation rates in OPEC countries, although these increases are not significant. Other oil price shocks will only lead to higher inflation in these countries without affecting OPEC's economic growth