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Induced pluripotent cells have been considered as one of the most recent and best cell sources for the cell therapy. In this study, the differentiation potency of human iPS cells, cultured on scaffolds, which can differentiate into definitive endodermal cells as precursor for hepatocytes, pancreatic and lung cells, was studied. Embryoid bodies composed of pluripotent cells, were seeded on electrospinning nanofiber scaffold. The cells were differentiated into definitive endoderm using IDE1. Expression of definitive endoderm markers including Sox17, FoxA2 and GSC were confirmed by immunocytochemistry staining and qRT-PCR analysis. In the present study, morphology and viability of cells were evaluated by utilizing a scanning electron microscopy and MTT assay, respectively. The results demonstrated the positive effect of 3D cultures, using suitable factors, on definitive endoderm differentiation.

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Chemical pesticides possess toxic and destructive impacts on the reproductive system and disrupt endocrine function. In this experimental study, the effect of movento, as a chemical pesticide, was investigated in comparison with chitosan, a biological pesticide, on the female reproductive system in vivo. In this study, 56 mice were randomly dived into 7 groups including control and experimental groups treated with movento and chitosan. After a 21-day treatment, mice were killed and their ovaries and blood being collected. In addition, the samples were fixed and stained with H & E method. The results exhibited that treatment with 2.5 and 5 mg/kg chitosan had no significant effect on the number and diameter of primary, secondary and antral follicles, while these items were significantly reduced in 10 mg/kg ch-itosan group and all movento-treated groups as well. In addition, the level of sexual hormones, such as estradiol, FSH and LH, was decreased in 10 mg/kg chitosan group and all movento-treated groups in comparison with the control gr-oup. The findings showed that movento affected the sexual hormone levels, ovary and ovarian follicle structure and in-duced abnormality in female reproductive system, while chitosan, as a biological pesticide, should be used due to its minimum effects on female reproductive system

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Nowadays, with the applications of titanium dioxide nanoparticles (TiO₂-NPs) in pharmacy, food industry, cosmetics, toothpaste and sunscreens, pregnant women are exposed to nanoparticles. Since tooth development is vuln-erable to environmental impacts and mandibular first molar bud develops before maxillary first molar bud, in this ex-perimental study the effects of TiO₂-NPs on the development of first mandibular molar bud in NMRI mouse was inve-stigated. Twenty five female NMRI mice were randomly divided into five groups (N=5); Control group (pregnant mice without any treatment), sham group (treated with distilled water), experimental groups 1, 2 and 3 (treated with 50, 150 and 500 mg/kg BW TiO₂-NPs, respectively, via gavage from embryonic days 10.5-14.5). On E14.5, embryos heads were prepared for histological examination and dental tissues were evaluated. Data were analyzed by ANOVA and post hoc test (Tukey). Microscopic observation showed tissue disorganization in experimental groups. Findings showed that in experimental groups 1 and 2, the diameter of bud and dental papilla and the length of dental bud decreased sign-ificantly. In experimental group 2, decrease in the diameter of dental follicle, dental bud and dental papilla and the le-ngth of dental bud was significant. On the other hand, in experimental group 3, only the decrease in the length of dental bud was significant. These findings showed that nano titanium dioxide can reduce the size of dental buds and is capable of preventing tooth development.

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Of different types of bio-compatible nano‌particles, iron oxide nanoparticle has attracted attention for its applications especially in medicine and magnetic resonance imaging (MRI). We decided to study histological changes in testis and spermatogenesis in mature male mice that are affected by ironoxide nanoparticles (Fe₂O₃) during fetal period. In this study, the mice were divided into three experimental and two control and sham groups. Iron oxide at do-ses of 10, 30, 50 mg/kg were injected into pregnant mice during 10th, 12th and 14th days of the critical period of fetus testis development. After the maturation of the mice which were born, slices with the thickness of 0.06 µm were prep-ared from adult male testis and epididymis, stained with hematoxylin and eosin. The cells were counted, then the obta-ined data was analyzed with one-way ANONA and Tukey testes. The results showed that the number of epididymis sp-erms at the doses of 10 and 30 mg/kg, testis weight at the dose of 30 mg/kg, primary spermatocytes at the dose 10mg/kg had increased, while the testis diameter in all the three experimental groups and the volume of the testis at the dose of 50 mg/kg had decreased. Disorganization and vacuolization were observed at high doses. Passing through the cell me-mbrane, and considering its oxidation and reduction potentials, it was observed that Iron oxide nanoparticle acts as anti-oxidant at low doses and shows toxicity at high doses. The fact obtained in the paper reflects the dual potential of the ir-on oxide nanoparticle.

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Irisin is a myokine secreted mostly by muscles after exercise, and its secretion level changes in metabolic disorders. The aim of present study was to investigate the effect of metformin on changes in the levels of plasma irisin, blood glucose and insulin resistance in male Sprague-Dawley rats receiving a high-fat emulsion diet. Twenty-four rats were divided into a normal control group (n = 8) and a high-fat diet group (n = 16). Then, high-fat diet group was divided into two subgroups, including high-fat diet control group (n = 8) and metformin group (n = 8). The normal control group received a standard diet. The high-fat diet control group received a high-fat emulsion diet containing corn oil by gavage on a daily basis for six weeks, and the metformin group received a high-fat emulsion diet with metformin (250 mg/kg/daily). At the end of the six-week period, factors such as glucose, insulin, irisin, Adiponectin, insulin resistance, liver enzymes, tumor necrosis factor α (TNF-α), serum lipid profile, lipid profile and lipid peroxidation in liver were measured and PGC-1α gene expression were examined in adipose tissue by Real-time PCR method. Liver histological tests with hematoxylin-eosin staining were performed to evaluate fat accumulation in liver tissue. Blood glucose level, insulin resistance, adiponectin, serum irisin level and liver lipid profile in the group receiving high-fat diet compared to the normal control group increased significantly (P <0. 05). Treatment with metformin caused a significant decrease in the level of these parameters compared to the high-fat diet group (P <0. 05) and an increase in the expression of PGC-1α gene in adipose tissue was observed in this group. As insulin resistance increased in rats receiving the high-fat diet, serum irisin level also increased, and with improving blood glucose and insulin resistance by metformin, serum irisin level was decreased. These results suggested that the elevated irisin levels may be a compensatory response to insulin resistance and impaired glucose metabolism. Hence, irisin could be considered as a potential target for the treatment of type 2 diabetes.