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...

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...

238 February 2015 A CUTE respiratory distress syndrome (ARDS) is a major cause of acute respiratory failure in critically ill patients. Despite improvements in understanding the pathophysiology of ARDS, its mortality remains high.1,2 Current treatments rely on supportive measures, such as lung-protective ventilation, conservative fluid management, and prone positioning.3–5 No pharmacological th...

objective: one of the major issues in bone tissue engineering is the design and fabrication of bioactive, bioresorbable porous 3d scaffolds capable of maintaining their structure and integrity over a predictable period of time. one such approach is the fabrication of composite scaffolds. methods: in this study we present fabrication and characterization of novel silk/bioglass-composite scaffold...

background: vhl (von hippel-lindau), runx-3 (runt-related transcription factor 3), e-cadherin (epithelial cadherin), p15 (ink4a, cyclin dependent kinase inhibitor), and p16 (ink4b) genes are essential in hematopoiesis. the aim of this study was to explore the correlation between gene expression and promoter methylation in cd34+ stem cells before and after differentiation to erythroid lineage. m...

background: in most mammals, the testis is always maintained at a lower temperature than that in the abdomen, and exposure of the testis to body temperature causes degeneration of germ cells. objective: in this research, the long effect of heat exposure on sperm parameters and microstructure of mouse testis were investigated. cryptorchid mouse were induced by exposure to abdominal heat. materia...

The use of animal models in modeling of human genetic disease has many advantages. In some cases, however, this method may not be applicable due to some limitations, such as differences in tissue composition, anatomy and physiology of humans and animals. Isogenic human disease models are a population of cells that are selected or engineered to model a specific genetic disease, in vitro. They ar...

s:3115:"Background: During reproductive life, the human endometrium undergoes around 500 cycles of growth, breakdown and regeneration. This outstanding regenerative capability is the basis for cyclic endometrial preparation and its dysfunction is involved in pathological disorders. Endometrial regeneration is mediated by the existence of a specialized endometrial stem cell (SC) population recen...