Ten years ago, we reported that in adult human females the ovarian surface epithelium (OSE) is a source of germ cells. Recently, we also demonstrated that new primary follicles are formed by assembly of oocytes with nests of primitive granulosa cells in the ovarian cortex. The components of the new primary follicles, primitive granulosa and germ cells, differentiated sequentially from the OSE, ...

background: niche cells, regulating spermatogonial stem cells (sscs) fate are believed to have a reciprocal communication with sscs. the present study was conducted to evaluate the effect of ssc elimination on the gene expression of glial cell line-derived neurotrophic factor (gdnf), fibroblast growth factor 2 (fgf2) and kit ligand (kitlg), which are the main growth factors regulating sscs deve...

introduction: to evaluate the camp -mediated ibmx (3-isobutyle -1-methyl xanthin) and db-camp (dibutyryl camp) effects on differentiation of human embryonic stem cells (hescs) into nerve cells were the objectives of this study. methods: we have used royan h1 hesc- derived embryoid bodies with four treatment groups: six days treatment with ibmx (5×10 -4m) and db-camp (10 -9m) (referred to as cam...

background: the aim of this study was to investigate the percentage of the stem cells population in human endometrial tissue sections and cultured cells at fourth passage. methods: human endometrial specimens were divided into two parts, one part for morphological studies and the other part for in vitro culture. full thickness of human normal endometrial sections and cultured endometrial cells ...

objectives : stem cell (sc) therapy is a promising technique for tissue regeneration. this study aimed to compare the viability and proliferation ability of periodontal ligament stem cells (pdlscs) isolated from the periodontium of healthy and periodontitis-affected teeth to obtain an autologous, easily accessible source of scs for tissue regeneration in periodontitis patients. materials and me...

naturally the brain is ineffective in regenerating functional tissue after disease or injury, so to overcome these defects innovative curative strategies such as stem cell transplantation and tissue engineering have to be considered. researchers investigate the use of strategies to attain better functional repair results. one of the important challenges of effective transplantation is the deliv...