فهرست مطالب iraj ragardi kashani

Cryopreservation and in vitro maturation (IVM) of oocyte is becoming an important technique in infertility treatment and fertility preservation. Also it has been proposed to establish a genetic resource bank for endangered or commercially important animal species. The aim of this study was to evaluate viability, maturation and fertilization rate of mouse immature oocytes after single and stepwise vitrification procedure. Oocytes were obtained from 4 weeks old female mice 48h after intraperitoneal injection of 7.5 IU pregnant mare serum gonadotropin (PMSG). Collected oocytes before vitrification were exposed to cryoprotectant, which was composed of 30% (v/v) ethylene glycol, 18% (w/v) Ficoll-70, and 0.3 M sucrose, either by single step or in a step-wise way. After vitrification and storage in liquid nitrogen, the oocytes were warmed and washed two times in medium TCM199 and then subjected to IVM, fertilization and subsequent development to blastocysts. The oocytes survival rates after vitrifying-warming (88.96%), maturation rate (73.23%), the capacity of fertilization (57.80%) and embryonic development to blastocyst (16.41%) in the step-wise exposure were significantly higher (p<0.001) compared with corresponding rate in the single step procedure. The results suggest that vitrification with step-wise procedure has positive effects on maturation and developmental capacity of mice germinal vesicle oocytes in compare with single step vitrification procedure.

Abstract: This study was designed for evaluation of epiphyseal plate histological changes of femur bones in osteopetrotic op/op mice.In this study 5 osteopetrotic op/op mice which were purchased from the commercial source were used.The animals were killed by overdose of chloroform and their femur bones were extracted. The bones were fixed in 10% formaldehyde and decalcified by HCl (0.6N), and routine histological processing were performed. The sections were stained by H&E methods and studied by conventional light microscopy. The results showed that, proliferative zone (PZ) and especially hypertrophic zone (HZ) were much thickened. In the ossification zone, trabecular bones were irregular and atypical osteoblast cells were observed. The osteoclast cells were not attached to trabecular bones. The bone marrow cavity was restricted and bone marrow cells were poor and scattered. Findings of the present investigation are similar to those reported about epiphyseal plate in osteosclerotic (OC) mice in which epiphyseal plate especially hypertrophic zone was thickened and chondrocytes were not substituted for osteoblasts in calcified cartilage area. Also, osteoclast cells had been inactive or absent in OC mice. For prevention of other complication due to the epiphyseal plate changes in new borne, suitable and punctually treatment protocols such as prescription of Macrophage Colony Stimulating-Factor (MCS-F) could be useful.