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  Background & Objectives: Stem cells are fundamental supporter of multicellular tissue. They allow blood, bone, gametes, epithelia, nervous system, muscle, and other tissues to be replaced by fresh cells throughout life. In recent years human Wharton’s jelly stem cells (WJSCs) have gained attention. They express a number of surface markers characteristic of mesenchymal stem cells. In this study, human Wharton’s jelly stem cells were isolated using explant method. To show the stemness property of these cells, three CD markers including CD105, CD44 and CD34 were tested.

  Methods: The umbilical cord samples were collected by Caesarian section at Arta Hospital in Ardabil. Cords were transferred in sterile conditions and stem cells were isolated using explant method. After log phase, cells were passaged then growth characteristics and CD105, CD44 and CD34 markers investigated by RT-PCR.

  Results: Separation of human Wharton’s jelly stem cells were started after 7 days. WJSCs in culture revealed two distinct cell population named Type 1 and Type 2. RT-PCR results showed that WJSCs were CD105⁺, CD44⁺ and CD34^-.

  Conclusion: Human umbilical cord stem cells could be an alternative source instead bone marrow stem cells for cell therapy and tissue engineering. These cells have a fibroblastic appearance. Following the lag phase and into log phase respectively, cells grow easily in culture and retain stemness properties in higher passages.

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Background & objectives: Several studies have described VacA and CagA as the two important virulence determinants of Helicobacter pylori, which are associated with gastric ulcer (GU) and duodenal ulcer (DU). The aim of present study was to determine the associations of the i and d regions genotypes of H. pylori vacA gene and cagA status with GU and DU risk.

Methods: A total of 177 isolates were cultured from the biopsies of Iranian patients with different geographic origins and genotyped. Data were collected and analyzed.

Results: Frequency of the vacA i1, i2, i1i2, d1, and d2 alleles and cagA in all patients was 42.9%, 55.4%, 1.7%, 41.8%, 58.2% and 68.4%, respectively. There was a significant difference between the frequencies of vacA i1 in isolates from GU than those from non-atrophic gastritis (p<0.05). When the GU was considered as a dependant factor by the multiple logistic regression analysis, the vacA i1 genotype was significantly associated with the age- and sex-adjusted risk for GU (p=0.006, odds ratio [OR]=3.56 95% confidence interval [CI]=1.45–8.75). Statistical analysis showed no significant association between vacA d genotype and digestive diseases. After controlling for age and sex variables, the cagA genotype remained in the final model when the DU was considered as a dependant factor by the the multiple logistic regression analysis (p=0.021, OR=3.77 95% CI=1.22-11.60).

Conclusion: We have proposed that the H. pylori vacA i1 and cagA genotypes could be considered as benefit biomarkers for prediction of risk of GU and DU in Iran, respectively.

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Background & Objectives: Breast cancer is one of the most common cancers of women in the world. Apoptotic pathway is one of the most important pathways to deal with cell damage, especially cancer, which is usually blocked in this disease. One of the main enzymes to set up this pathway is JNK (1,2,3α,3β), which is activated by cellular stress.
Methods: In this study, breast cancer cells with the origin of MCF-7 cell lines were cultured in RPMI medium using 10%fetal bovine serum.Then , they were subjected to heat (42 & 45 ^̊ C) for 1,2,4,6 and 8 hours under X-ray and γ-ray radiations for 1,2,3 and 4 hours as well. Their viability and enzyme level were evaluated by MTT and ELISA tests, respectively.
Results: The obtained results showed that abiotic stresses including heat and radiations resulted in JNK level increase and recovery of apoptosis pathway function in breast cancer cells. In addition, they led to decreased of cell viability and increase of JNK level depending on the duration and kind of stress.
Conclusion: The results in this study showed abiotic stress directly affected the JNK level. Increase of this enzyme in the cell resulted in activity of JNK apoptosis pathway. We hope to find methods to help to cancer treatment by means of more studies on JNK enzyme and relevant pathways.

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Background & objectives: Tissue engineering is a growing field to repair and replace the defective function of damaged tissue or organ, and today it is proposed as a new treatment to replace conventional transplant methods. For this purpose, polymeric biomaterials (scaffolds) and living cells are used. The purpose of this study is to fabricate polycaprolactan (PCL) nanoscaffold and load silymarin on the nanoscaffold to check the biocompatibility and proliferation ability of pc12 cells on it.
Methods: In order to prepare polycaprolactan nanoscaffold and load silymarin on it, 7% polycaprolactan solution (dissolved in acetic acid) was mixed with silymarin solution with a concentration of 0.9% (weight percent), and then the scaffold was prepared using electrospinning device. The morphology of the scaffold was evaluated by scanning electron microscope (SEM) and the chemical structure of the scaffold was evaluated by ATR-FTIR spectroscopy. Toxicity of the scaffold and cell survival of PC12 cells were investigated by MTT test and SEM microscope respectively.
Results: Examining the morphology of the scaffold and its chemical structure showed the appropriate porosity of the scaffold and the successful loading of silymarin on the PCL scaffold. The toxicity of the scaffold was investigated 24, 48 and 72 hours after the cultivation of PC12 cells, and the results showed an increase in cell viability and proper attachment of cells on the scaffold.
Conclusion: The results of this research showed that the loading of silymarin on polycaprolactan scaffold increases the proliferation and survival of PC12 cells. Therefore, this scaffold can be a suitable candidate for nerve tissue engineering.