BackgroundBacterial resistance to antibiotics has become a major source of concern for public health. Pseudomonas aeruginosa strains are important opportunistic pathogens. These bacteria have a high resistance to a wide range of existing antimicrobials and antibiotics.ObjectivesThe present study was performed to evaluate the frequency of KPC in P. aeruginosa isolated from clinical samples of educational hospitals of Arak University of Medical Sciences, using the mentioned phenotypic and genotypic methods.Materials and MethodsOne hundred and eight non-duplicate clinical isolates of P. aeruginosa were collected from hospitals of Arak University of Medical Sciences, Arak, Iran. Antibacterial susceptibility was determined by the disk diffusion method. KPC production was confirmed by the Modified Hodge Test (MHT), which is a phenotypic test, and combined-disk test with boronic acid and the Polymerase Chain Reaction (PCR).ResultsIn the present study, 13 isolates (12%) of P. aeruginosa were positive for KPC, using PCR. Comparison of the two phenotypic methods used in this study showed that boronic acid is more sensitive than MHT in identification of KPC-producing strains (84.6% vs. 77%).ConclusionsUtilization of reliable methods for identifying carbapenemase-producing strains and determining their antibiotic resistance pattern could have a very important role in treatment of infections caused by these strains. A substantial amount of P. aeruginosa isolated from clinical samples of hospitals in Arak (Iran) produce KPC carbapenemase. Due to their low specificity, MHT and boronic acid phenotypic methods could not completely identify KPC-producing P. aeruginosa. However, the sensitivity of boronic acid phenotypic method in detection of KPC was higher than MHT.

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Background: Organisms producing CTX-M-lactamases are known as the source of resistance to Oxyiminocephalosporins such as Eeftriaxone and Ceftazidime. However, the laboratory detection of these strains is not well defined. Objectives: The aim of this study was to determine the presence and prevalence of known CTX-M-beta-beta-lactamase genes in clinical isolates of Enterobacteriaceae from Arak educational hospitals, Iran. Materials and Methods: During a 10-month period (May to February 2010), 350 randomly Enterobacteriaceae isolates were obtained from the clinical laboratories of different hospitals of Arak University of Medical Sciences, Iran. Antibiotic susceptibility was tested by CLSI disk diffusion and extended spectrum beta-lactamase (ESBL) confirmatory tests. Minimum Inhibitory Concentration (MICs) was determined by broth micro dilution. All of the ESBL-producing isolates were examined by PCR to detect the presence of bla CTX-M genes. Results: In phenotypic confirmatory test, 154 (44%) out of 350 clinical isolates were ESBL positive. Using molecular assay, 154 strains potentially producing extended-spectrum-beta -lactamases were examined for the presence of CTX-M enzymes. 92.2% isolates CTX-M -1, 28.5% isolates CTX-M-2, 17.5% isolates CTX-M-8, and 38.3% isolates CTX-M-9 genes detected by PCR. Conclusions:The levels of resistance to Ceftazidime were remarkably variable among CTX-Mproducers. This study provides further evidences of the global dissemination of CTX-M type ESBLs and emphasized on the need for their epidemiological monitoring.

Walnut oil significantly reduced disease severity, inhibited plaque formation, and altered cytokine production. More studies are required to identify the mechanism of action of walnut oil as a valuable supplement in the treatment of MS.

Stroke continues to be a major cause of death and disability worldwide. In this respect, the most important mechanisms underlying stroke pathophysiology are inflammatory pathways, oxidative stress, as well as apoptosis. Accordingly, miRNAs are considered as non-coding endogenous RNA molecules interacting with their target mRNAs to inhibit mRNA translation or reduce its transcription. Studies in this domain have similarly shown that miRNAs are strongly associated with coronary artery disease and correspondingly contributed to the brain ischemia molecular processes. To retrieve articles related to the study subject, i.e. the role of miRNAs involved in inflammatory pathways, oxidative stress, and apoptosis in stroke from the databases of Web of Science, PubMed (NLM), Open Access Journals, LISTA (EBSCO), and Google Scholar; keywords including cerebral ischemia, microRNA (miRNA), inflammatory pathway, oxidative stress, along with apoptosis were used. It was consequently inferred that, miRNAs could be employed as potential biomarkers for diagnosis and prognosis, as well as therapeutic goals of cerebral ischemia.

Background:Toxoplasma gondii is an obligatory intracellular protozoan parasite, which infects human beings. Since the current antigens used for diagnosis or vaccination are contaminated with non parasitic material in which the parasite is grown, it is tried to produce recombinant antigens to design vaccines against toxoplasmosis, or make diagnostic kits. Choosing the type of antigen to produce recombinant vaccine or diagnostic kits is considerably important. The rhoptry protein 1 is one of the excretory-secretary antigens of Toxoplasma which seems to be an appropriate candidate in production of recombinant vaccines and diagnostic kits. Objectives: The current study aimed to produce rhoptry protein 1 from Iranian strains of Toxoplasma for further investigations. Materials and Methods: Genomic DNA was isolated from tachyzoite of parasite by phenol chloroform method and gene fragment was amplified by polymerase chain reaction. The polymerase chain reaction products were ligated into restriction enzymes sites of pTZ57R/T cloning vector. The product was sub-cloned into a prokaryotic expression plasmid (pET32a). The recombinant expression vector containing rhoptry protein 1 sequence was transformed into Escherichia coli BL21 pLysS and was induced by isopropyl β-D-1-thiogalactopyranoside. The sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blotting methods were used to confirm the production of protein. Results:The result showed that the desired molecular weight protein is produced. Recombinant protein was confirmed by western blot using Ni-NTA-conjugate. Conclusions:The result of this study showed that recombinant ROP1 Toxoplasma was produced successfully. In the present study, unlike other studies, the goal was to express full length of ROP1. Also this protein was produced alone not fused with other proteins.

Background:Enterococcal species have emerged as important pathogens in Iran as well as throughout the world. With the increased use of vancomycin, Vancomycin-Resistant Enterococci (VRE) has become an important nosocomial pathogen.Objectives:The aim of the present study was to determine the incidence and antimicrobial susceptibility pattern of VRE and also to determine the most important genes that cause resistance to vancomycin in clinical samples in Arak, Iran.Materials and Methods:In total, 200 enterococci samples were collected from clinical specimens of Arak hospitals. Enterococcal species were identified using standard biochemical tests. Antibiotic susceptibility was tested by the Clinical and Laboratory Standards Institute (CLSI) disk diffusion. Minimum Inhibitory Concentration (MICs) was determined by broth micro dilution. All of the VRE isolates were examined by PCR to detect the presence of VRE genes.Results:Disk diffusion agar showed that 96 strains (48%) were resistant to gentamicin, 89 (44.5%) to ciprofloxacin, 127 (63.5%) to erythromycin, 142 (71%) to tetracycline, 11 (5.5%) to teicoplanin, 32 (16%) to vancomycin, none to linezolid and 96 (48%) to co-trimoxazole. The MICs of the resistant isolates were as follows; 88 strains had MIC ≥ 32 μg/mL to vancomycin and 59 strains had MIC ≥ 32 μg/mL to teicoplanin. Molecular studies revealed that 59.09% of VRE contained VanA genes and 7.95% of VRE contained the VanB genes. None of the strains had vanC1 and vanC2/3 gene.Conclusions:According to the results of this study, rates of vancomycin-resistance in enterococci, in Iran like other parts of the world, is increasing. Therefore accurate methods are required for identifying strains that possess resistance genes because many cases of hospital infections are caused by these strains.

: Photoreceptor loss is a major cause of blindness around the world. Stem cell therapy offers a new strategy in retina degenerative disease. Retinal progenitors can be derived from embryonic stem cells (ESC) in vitro, but cannot be processed to a mature state. In addition, the adult recipient retina presents a very different environment than the photoreceptor precursor donor. : It seems that modulation of the recipient environment by ectopic development regulated growth factors for transplanted cells could generate efficient putative photoreceptors. The purpose of this review article was to investigate the signaling pathway of growth factors including: insulin-like growth factors (IGFs), fibroblast growth factors (FGF), Nerve growth factor (NGF), Brain-derived neurotrophic factor (BDNF), Taurin and Retinoic acid (RA) involved in the differentiation of neuroretina cell, like; photoreceptor and retinal progenitor cells. Given the results available in the related literature, the differentiation efficacy of ESCs toward the photoreceptor and retinal neurons and the important role of growth factors in activating signaling pathways such as Akt, Ras/Raf1/ and ERKs also inhibit the ASK1/JNK apoptosis pathway. Manipulating differentiated culture, growth factors can influence photoreceptor transplantation efficiency in retinal degenerative disease.