Accessory gene regulator types of Staphylococcus aureus isolated in Gorgan, North of Iran

Background: Staphylococcus aureus is a gram-positive bacterium that has remained a persistent pathogen, causing infections such as endocarditis, meningitis, and toxic shock syndrome in humans. The accessory gene regulator (agr) system of Staphylococcus aureus is responsible for controlling the expression of many genes that code for virulence factors. In this study, we assessed the S.aureus agr Group, based on their source of isolation, in Gorgan, North of Iran. Materials and Methods: DNA of 194 S. aureus isolates was extracted by lysozyme-phenol chloroform method, which included 85 clinical samples, 58 samples which were isolated from noses of health care workers and 51 cases which were obtained from food products in Gorgan, northern Iran. PCR-based assays were used to evaluate agr locus nucleotide polymorphism for the identification of agr specificity Group. Distributions of each agr Group were determined and comparison between different sources was assessed by X2. A p-value of <0.05 was considered as significant. Results: The majority of isolates belonged to agr Group I (43.3%), followed by agr Group III (28.87%), agr Group II (22.68%), and agr Group IV (5.15%). In our study, a majority of S. aureus isolates were recovered from health care workers and food product specimens were of agr Group I and isolates which were recovered from patients were of agr Group III. These differences were statistically significant (P=0.005). There was no statistical difference between the source of isolation of clinical samples of S.aureus and agr type. Conclusion: Agr Group I was predominant among health care workers and food product specimens in Gorgan, North of Iran, but in strains which were isolated from patients, agr Group III was predominant. Investigating the possible role of agr Group III in Staphylococcus aureus infection in future studies is recommended

Analysis of Receptor’s Distribution in Entorhinal Cortex after Induction of Spreading Depression in Juvenile Rats

Spreading depression (SD), discovered by Leao in 1944, is a pathophysiological wave which propagates slowly in the brain (3 mm/min) and cause dramatic ionic and hemodynamic changes. SD appears to act through several mechanisms and receptors which have not completely understood. Here, we studied the effect of inhibitory system in animal model of SD using immunohistochemistry technique. After implanting recording electrodes and cannula over the brain, repetitive SD was induced by KCl injection (2 M) in juvenile rats for four consecutive weeks. Then all rats were decapitated and the brains removed. Mean number of dark neurons in entorhinal cortex were determined using Toluidine blue staining. To identify the prevalence and distribution of γ-aminobutyric acid A (GABA-A) subunit receptors and glutamic acid decarboxylase (GAD), immunohistochemistry technique was performed. The mean number of SD induced by KCl injection was statistically increased during four weeks of experiments (P=0.036). The mean number of dark neurons in entorhinal cortex was significantly increased in SD group compared to sham rats (P≤0.001). Also, expression of GAD 65 receptor in the Entorhinal cortex significantly increased in SD group compare to control group (P<0.05). GABA-Aα and GABA-Aβ receptors didn’t show significant change in that region. These data suggest that SD is able to damage neural cells and also it could lead to enhancement of GAD, the enzyme which is responsible for synthesizing an important inhibitory neurotransmitter, GABA receptor, in the central nervous system. Keywords: Cortical Spreading Depression, Entorhinal Cortex, Gamma-Aminobutyric Acid

Lipid peroxidation in the serum of hypothyroid patients (In Gorgan-South East of Caspian Sea)

This study was designed to determine if lipid peroxidation can be modified by hypothyroidism. Twenty eight subjects with hypothyroidism and 33 euthyroid subjects participated in this study (2007). Blood samples were collected and serum malondialdehyde, T3, T4 and TSH were measured. An increase in lipid peroxidation (expressed as Malondialdehyde, MDA) and TSH levels and also a decrease in T4 level were observed in the hypothyroid patients when compared with control groups (p<0.001). The level of T3 was not changed when compared with control groups. The results shows that hypothyroidism may not modulate the free-radical-induced oxidative damage and that hypothyroidism may not present some protection against lipid peroxidation. Thus, the enhancedlipid peroxidation may play a role in the free-radical-induced oxidative damage of some tissues in hypothyroidism. These may show that there is an important relation between hypothyroidism and lipid peroxidation. © 2008 Academic Journals Inc

The Frequency of MRSA carriers in health care workers in Gorgan, North of Iran

Methicillin resistant Staphylococcus aureus (MRSA) is one of the most important pathogen in hospitals. Healthcare personnel are the main source of nosocomial infections and identification and control of MRSA carriers can reduce incidence of infections. The aim of this study was to determine the frequency of methicillin resistant Staphylococcus aureus (MRSA) and their antibiotic susceptibility profile among healthcare workers in Gorgan located in northern Iran. Three hundred and thirty three of healthcare workers were participated in this cross-sectional study in 2010. Samples were taken with sterile cotton swabs from both anterior nares. Swabs were plated onto Mannitol salt agar. S. aureus were identified by Gram stain, Catalase, Coagulase and DNase tests. MIC (micro dilution broth) method was used to determine resistance of strains to methicillin. Antimicrobial susceptibility pattern to other antibiotics was performed by diffusion method. Frequency of S. aureus and MRSA carriers among healthcare workers was 24% (80.33) and 3% (10.33) respectively. MIC of isolates was varied between 0.5 and 65.31 (39%) of cases were showed MIC of intermediate that ranged between 4 and 8. Penicillin and Imipenem resistance were seen in 97.5% and 1.4% of isolated S. aureus strains, respectively. Frequency of S. aureus carriers in healthcare workers in our area was median in compare with other region in Iran but the MRSA carriage in healthy staff was lower than most part of Iran. It would be considering to monitor healthy carrier staff because of high rate intermediate MIC in this group to prevent conversion to MRSA

Andreev Bound states as a phase sensitive probe of the pairing symmetry of the iron pnictide superconductors

A leading contender for the pairing symmetry in the Fe-pnictide high temperature superconductors is extended s-wave $s_\pm$, a nodeless state in which the pairing changes sign between Fermi surfaces. Verifying such a pairing symmetry requires a special phase sensitive probe that is also momentum selective. We show that the sign structure of $s_\pm$ pairing leads to surface Andreev bound states at the sample edge. In the clean limit they only occur when the edge is along the nearest neighbor Fe-Fe bond, but not for a diagonal edge or a surface orthogonal to the c-axis. In contrast to d-wave Andreev bound states, they are not at zero energy and, in general, do not produce a zero bias tunneling peak. Consequences for tunneling measurements are derived, within a simplified two band model and also for a more realistic five band model.Comment: 5 pages, 5 figure

Effects of intermittent fasting on experimental autoimune encephalomyelitis in C57BL/6 mice

Several religions recommend periods of fasting. One of the most frequently asked questions of MS patients before the holy month of Ramadan is weather fasting might have an unfavorable effect on their disease course. This debate became more challenging after the publication of experimental studies suggesting that calorie restriction prior to disease induction attenuates disease severity. We conducted this study to assess early and late effects of fasting on the animal model of MS, known as autoimmune encephalomyelitis. EAE was induced in the C57BL/6 mice, using Myelin Oligodendrocyte Glycopeptide (MOG) 35-55 and they fasted every other day either after the appearance of the first clinical sign or 30 days after disease induction for ten days. Thereafter, the mice were sacrificed for further histological and immunological evaluations. Intermittent fasting after the establishment of EAE did not have any unfavorable effect on the course of disease. Moreover, fasting at the early phase of disease alleviated EAE severity by ameliorating spinal cord demyelination. Fasting suppressed the secretion of IFN-γ, TNF-α and raised IL-10 production in splenocytes. Fasting was also associated with a lower percent of cytotoxicity. Intermittent fasting not only had no unfavorable effect on EAE but also reduced EAE severity if started at early phase of disease. © Summer 2016, Iran J Allergy Asthma Immunol. All rights reserved

Mutations in pre-core and basal-core promoter regions of hepatitis B virus in chronic HBV patients from Golestan, Iran

Objective(s): It has been reported that the mutation of the pre-core (PC) and basal-core promoter (BCP) may play an important role in the development of HBV-related hepatocellular carcinoma (HCC). In this study the PC and BCP mutations were investigated in chronic HBV patients. Materials and Methods: In this study, 120 chronic HBV patients from Golestan, Northeast of Iran who were not vaccinated against HBV, were recruited from the year 2008 to 2012. HBV-DNA extraction from plasma and PCR were performed and positive PCR products were subjected to automated sequencing. Results: One hundred out of 120 (83.3%) patients were HBeAg negative. Comparison of our nucleotide sequences with reference sequence showed high rate mutation in BCP and PC region (96.66%). Frame shift mutation was found in 78 (65%) of patients in BCP region, among them 8 (6.6%) patients showed mutation in PC region. Conclusion: Our results demonstrated high rate of mutations in BCP and PC regions among HBV chronic patients in Northeast of Iran

Alleviation of experimental allergic encephalomyelitis in C57BL/6 mice by Soy Daidzein

Experimental allergic encephalomyelitis (EAE) is considered as the murine model of multiple sclerosis. Daidzein a phytostrogenic compound of soy is known to impose immunomodulatory and antioxidative effects. We conducted this study to assess the potential protective and therapeutic effects of daidzein on allergic encephalomyelitis. C57BL/6 mice were induced with allergic encephalomyelitis using myelin oligodendrocyte glycoprotein (35-55) and received daidzein or dimethyl sulfoxide as the vehicle control. To assess the protective effect of daidzein, the mice were administered with 20 mg/kg of daidzein from 21 days prior to 21 days post EAE induction on a daily basis. To evaluate the therapeutic effect of daidzein, mice were fed with 300 mg/kg daidzein after the appearance of the first clinical signs for 10 days. One day after the last gavage, the mice were sacrificed. Spleen and brain were removed for further histological and immunological analysis. Feeding mice with low dose of daidzein prior to disease induction did not affect disease severity. However, treating with high dose of daidzein after the onset of the disease reduced interferon-3 and interleukin-12 secretion, enhanced interleukin-10 production, suppressed lymphocyte proliferation, and decreased cytotoxicity as judged by lactate dehydrogenase release. In conclusion, daidzein reduced the extent of demyelination and disease severity. Chronic oral therapy with low dose of daidzein did not prevent experimental autoimmune encephalomyelitis. However, high doses of daidzein could prohibit disease exacerbation. © Summer 2014, Iran J Allergy Asthma Immunol. All rights reserved