The reproductive system of human female exhibits a much faster rate of aging than other body systems.Ovarian aging is thought to be dominated by a gradual decreasing numbers of follicles,coinciding with diminished quality of oocytes.Menopause is the final step in the process of ovarian aging.This review focuses on the mechanisms underlying the ovarian aging involving a poor complement of follicles at birth and a high rate of attrition each month,as well as the alternated endocrine factors.We also discuss the possible causative factors that contribute to ovarian aging,e.g.,genetic factors,accumulation of irreparable damage of microenvironment,pathological effect and other factors.The appropriate and reliable methods to assess ovarian aging,such as quantification of follicles,endocrine measurement and genetic testing have also been discussed.Increased knowledge of the ovarian aging mechanisms may improve the prevention of premature ovarian failure.
LI QianGENG XiaoDanZHENG WeiTANG JieXU BoSHI QingHua
Recently, the study on "induced pluripotent stem cells" (iPS cells) has made a great breakthrough, and it is considered as a new milestone in the history of life science. This progress has updated our tradi-tional concepts about pluripotency control, and provided people with a brand-new strategy for somatic cell nuclear reprogramming. In virtue of its availability and stability, this method holds great potential in both biological and clinical research. In order to introduce this rising field of study, this paper starts with an overview of the development of iPS cell establishment, describes the key steps in generating iPS cells, elaborates several relevant scientific issues, and evaluates its current restrictions and promises in future research.
