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Background and Objective: The modern life condition has caused the human to be exposed to electromegnetic fields. Epidemiologic and animal laboratory studies have illustrated the adverse effects of electromegnetic fields on biologic systems. The aim of study was to assess the effects of low density electromegnetic on heart tissue of male rat. Materials and Methods: In this experimental study 30 Wistar rats with weight of 10-150 gram and 5weeks age were used. Rats were allocated randomly in two aqual groups: case and control. Experimenal group rats were exposed to the electromegnetic field 8 hours a day for 2 months (50 HZ, 1 mili Tesla). After 2months the rats were sacrified, the heart tissues were removed and stained by H&E method. Results: There was not any altherations in cells and tissue of control groups. In experimental group there was a sever disruptions on heart tissue, polymorphysm of cardic myocyte nuclues with same hollow spaced in perinucluar, nuclear cytoplasem and fibrotic tissue. Also, the number and size of cells in case group were reduced. Cagulated necrosis and vacolization of cytoplasm of cardiac myocyte was observed in case group. Conclusion: This study showed that low density of electromegnetic Fields for two months durtion can cause pathological changes in cells and heart tissue of male rats.

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Background and Objective: Leptospirosis is an infectious and zoonosis disease, which is caused by leptospira and is transmitted from animal to human. The rapid diagnosis can control the disease, therefore this study was carried out to determine the prevalent serovars of leptospira using micro agglutination test (MAT) in human and cattles. Method: In this descriptive study, 175 cattles and 67 suspected human serum samples were tested in five provinces in Iran during 2011-12. Serum samples tested by micro agglutination test using 20 live leptospira serogroup. Results: Ninty nine out of 175 (56.5%) cattle serum samples and 31 out of 67 (46.2%) human samples were positive against leptospira antigen. The most prevalent leptospira serovar in cattles and human were Serjoe hardjo (61.9%) and Serjoe serjoe (23%), respectively. The most frequent titer in positive samples was equal to be 1/400. Fifty percent of human positive samples belong to farmers between 20-40 years old. The common contaminations belong to polluted water (61.1%) and infected blood (28.3%), respectively. Conclusion: Using micro agglutination test, the most prevalent leptospira serovar in cattles was Serjoe hardjo and in human was Serjoe serjoe.

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Background and Objective: The adoption of methods for increasing the shelf life of dairy products by using natural preservatives is necessary. This study was done to determine the antimicrobial activity of aqueous extract of orange peel and its effect on the shelf life of flavored milks.

Methods: In this descriptive –analytical studty the antimicrobial activity of aqueous extract of orange peel was investigated by using disk diffusion method and minimum inhibitory concentration (MIC) by successive dilution of culture broth and then its impact on the shelf life of milk.

Results: In disk diffusion method and MIC the antimicrobial effect of aqueous extract of orange peel was more effective against Staphylococcus aureus and Candida albicans and less effective on Escherichia coli. The growth diameter of disk diffusion method in aqueous extract of orange peel was 7.11, 29.06 and 50 mm for Staphylococcus aureus, Escherichia coli and Candida albicans, respectively. The inhibitory concentration in the aqueous extract of orange peel was 15, 2 and 2 mg/ml, respectively. Also 0.17 g/ml of aqueous extract of orange peel in milk reduced the growth of microorganisms at the time of 6, 12, 24, 48 and 72 hours. Temperature affected the growth of Candida albicans in the milk, so that the growth of microorganisms reduced with decreasing temperature (P<0.05). The growth inhibitory activity of the aqueous extract of orange peel on Staphylococcus aureus was significantly more than on Escherichia coli (P<0.05).

Conclusion: This study showed that the antimicrobial activity of aqueous extract of orange peel on Staphylococcus aureus, Escherichia coli and Candida albicans in vitro and in the milk.

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Background and Objective: Memantine (MEM) an uncompetitive N-methyl-D-aspartate receptor antagonist is used for treatment of patients with Alzheimer disease. This study aimed to examine the effect of Memantine on the spatial learning and memory in electrical lesion’s model of nucleus basalis magnocellularis (NBM) in animal model of Alzheimer's disease.
Methods: In this experimental study, 56 adult male Wistar rats were allocated into eight groups: control group; lesion group, which received bilateral electrically lesion (0.5 mA, 3s) in NBM; sham group (the electrode was entered into the NBM with no lesion); Memantine groups (lesion+1 mg/kg/bw of MEM; lesion+3 mg/kg/bw of  MEM; lesion+5 mg/kg/bw of  MEM; lesion+7 mg/kg/bw of MEM) and Vehicle group (lesion+0.2 mL saline). After one week, animals were trained to perform the Y-maze task for five days. Twenty five days after training, a retention test was performed to determine long-term memory.
Results: The bilateral lesion of NBM impaired the spatial learning compared to the control and sham groups (P<0.05). No effect on spatial learning was seen in saline group compared with the lesion group. The treatment with Memantine in  lesion+MEM 3 mg/kg/bw, lesion+MEM 5mg/kg/bw and lesion+MEM 7mg/kg/bw groups significantly improved spatial learning (P<0.05). Moreover, no significant difference of memory was observed between the results in the 5th day of training and the retention test of the 30th day.
Conclusion: Treatment with memantine improves spatial learning defects in electrical leisions model of NBM of Alzheimer's disease in dose dependent manner in animal model.

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Background and Objective: Salmonella is one of the most important zoonotic pathogens responsible for food-borne infections all over the world. Poultry products are widely acknowledged to be a significant reservoir for Salmonella. This study was done to evaluate the antibiotic resistant of Salmonella enterica producer of beta lactamase spectrum in poultry.
Methods: In this descriptive – laboratort study 70 Salmonella enterica serotypes were collected from poultry. All Salmonella isolates were tested to antimicrobial susceptibility testing by the Kirby-Bauer disk diffusion according to Clinical Laboratory Standards Institute (CLSI). Twenty-nine antibiotics were used in this study. Klebsiella pneumoniae; ATCC 700603 was used as quality control strains. The isolates were determined to be ESBL-producing Salmonella by the conventional double-disk synergy and genotypic method.
Results: Among 70 salmonella isolates, the most prevalent serotypes were S.typhimurium and S.enteritidis. All serotypes were susceptible to gentamicin, ciprofloxacin, oflaxacin, imipenem, enrofloxacin. The common resistance was observed to cephalexin (96%), cefazolin (96%) and cephalotin (65%). Among the 70 Salmonella isolates studied, multi-drug resistance was observed in 59 (84%) isolates. Forty-seven (67%) isolates were found to be ESBL-producing isolates. PCR assay of all isolates showed that 17 isolates (33.3%) carried bala CMY2 gene.
Conclusion: This study showed that antibiotic resistance to Salmonella enterica serotypes is due to beta lactamase enzyme in this strain is considerably increased in poultry.