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Introduction:Final examinations are important stressors in schools and universities that result in different psychoneuroimmunological outcomes but the study of these effects on children has not been paid enough attention to. The aim of this study is to investigate the effect of final examinations on salivary immunoglubulin A in children. Materials and Methods: In this clinical trial a total of 100 children (50 boys, 50 girls) in 5th grade, aged less than 12 years from two primary schools of 5th educational district in Tehran were choosen randomly. The subjects completed Test Anxiety Scales of Sarason & Abolghasemi. After making sure of their physical and mental health by reviewing their medical history, clinical examinations and after controlling sleep, food, drug and sport variables, based on time series design, salivary IgA samples were taken five times as followed: one week before and then three times through mathematics, history and science exams and at last one week after passing the exams at, 9 to 10 am. IgA samples were analyzed by nephlometry method. Data was analyzed using ANOVA. Results: Findings indicated that IgA level was decreased significantly during examinations comparing to IgA levels before and after examinations (p=0.01). The relations of sex and anxiety scores were not statistically significant. It means that decreased IgA levels are the same in all children. Conclusion: Final examinations as a stress resource, diminishes IgA and this change is not related to sex and test anxiety score.

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Introduction: Celiac disease (CD) or gluten-sensitive enteropathy is a malabsoption of nutrients due to hyoersesitivity of gluten. Some etiologic facrors are environmental, immunologic and genetic factors. The frequancy of Celiac disease is not studied in western regions of Iran, therefore this study is done to determine the frequancy of Celiac disease in general population of rural regions of Arak. Materials and Methods: This is a descriptive, cross-sectional study in which 700 people between 20-56 years old in rural regions of Arak were selected by multistage random sampling (364 male and 336 female). After completing questionnaires, blood samples were collected and serum IgA levels (to rule out IgA deficiency), and serum t-TG Ab were assessed. All cases that had positive serologies and those who had high clinical probability of having Celiac disease underwent second duodenal segment biopsy. Data was presented using mean, standard deviation and frequency distribution. Results: Serum IgA levels were normal in all samples. 8 cases were positive for t-TG Ab, 38 cases had high normal levels of t-TG Ab and the others had less than 6 Au/ml t-TG Ab. Only in patients with high normal serology, histology was positive. 1% (10 in 1000 people) of all studied subjects demonstrated intestinal lesions due to Celiac disease. Most of them were asymptomatic. Conclusion: CD frequency in rural regions of Arak in people between 20-65 years old was 10 among 1000 cases. This frequency is the same as studies done in northern and southern regions of Iran but was higher comparing to the other parts of the word. This amplifiles the importance of screening of CD in Iran. Also the sensitivity and specificity of t-TG Ab was found high because all cases with high normal levels of t-TG Ab were approved by histology.

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Background: Candida species are the most common yeasts that reside in oral cavity in 30 - 50% of people, and are capable to produce opportunistic infections within the oral cavity. This study was done to determine the effect of cigarette smoking on the type and degree of Candida oral carriage. Materials and Methods: In this case-control study, oral Candida flora in 34 smoker and 66 non-smoker men were compared. All of the samples were collected by swab and examined by direct microscopy and culture on CHOROM agar Candida and corn meal agar media. Isolated colonies were identified by carbohydrate assimilation method using RapID Yeast PLUS System. Results: Out of the 34 smoker individuals, 27(79.4%) had Candida colonization in their oral cavity while 30(45.5%) of the 66 non-smoker individuals had developed this kind of colonization. A significant difference was observed between the two groups (p<0.05). Additionally, there was a significant difference in the degree of colonisation and the type of candida species which were isolated from the oral cavity of the smoker and nonsmoker groups. Conclusion: Cigarette smoking can act as an important underlying factor in oral candidiasis.

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origanum vulgare l.spp viride was used in ancient medicine and it was medicated for digestive disease, diabetes, remedy of trauma. While antimicrobial, ant diabetic, anticancer and antioxidant effect of this plant was proved but there is done no study for its effect on reproductive system. Therefore the purpose of recent study is surveying eventual androgenic effect of this plant on hormonal level of pituitary - gonadal axis in mature male vistar rats. Materials and Methods: recent study was done on five groups of male rats of vistar race and every group includes nine rats. The control group received no drug. The sham group received physiological serum and experimental groups of A, B and C were received the ethanolic extract of origanum vulgare l. with concentration of 40, 20, 10 mg/kg body weight respectively with gavaj for 14 days. Then levels of FSH, LH and TSH hormones in blood sample was measured with RIA method and obtaining result was compared between control group and other groups. Data was analyzed with SPSS software and statistical method of ANOVA and Tukey test. In this research, significant level was p<0.05. Results: in control group, sham group and A, B and C groups, respectively mean and standard deviation from average of plasma concentration for LH hormone based on mlU /ml were: 0.18±0.006, 0.183±0.017, 0.187±0.026, 0.241±0.012 and 0.284±0.027 And for FSH Hormone were: 0.321±0.025, 0.342±0.071, 0.372±0.026, 0.383±0.031 and 0.372±0.026 And for TSH hormone were: 5.28±0.683, 6.07±0.5, 6.09±1.94, 6.66±1.48 and 8.1±1.66. Conclusion: ethanolic extract of origanum vulgare leaf in maximum dose have androgenic effects and it can affect the activity of different levels of hypothalamic – pituitary – gonadal axis and increase the secretion of testosterone and gonadotropic hormones.

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Background: Shigellosis is a major global issue of human health. To date, no effective vaccine has been found against Shigella. One of the major virulent factors in Shigella dysenteriae type 1 is Shigella enterotoxin or STx. STxB has immunogenic, adjuvant, or carrier properties. Vaccine candidate antigens can be coupled with this adjuvant for production of an appropriate vaccine. IpaD has a key role in invasion, virulence, and infection by Shigella.

Materials and Methods: In this study, the gene sequences of STXB and ipaD were obtained from gene bank and corresponding genes were prepared as synthetic construct and then transferred to E. coli BL21DE3. By PCR amplification and enzymatic digestion, protein expression levels were assessed. Its protein expression was confirmed by Western blot technique. After extraction by affinity chromatography, the recombinant protein was injected four times to guinea pigs. The pigs were, then, challenged by Shigella felexneri 2a and active toxin of E. coli O157:H7.

Results: The results showed that groups of guinea pigs challenged with 28×LD₅₀ of  toxin  completely survived. Furthermore, guinea pigs were challenged by inducing Shigella felexneri 2a in their eyes. The results showed that the control pigs got cataracts, whereas the immune pigs were in health.

Conclusion: The findings of this study suggest that this recombinant protein is a good candidate for production of a recombinant vaccine against Shigella family.

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