Satellite cells, as the major stem cells, are responsible for postnatal skeletal muscle growth, regeneration and maintenance. As a result, satellite cells have great potential as therapeutic agents. Activation of satellite cells in vivo is a key link in the muscle regeneration processes. And their replenishment is necessary to keep the capacity of skeletal muscle to regenerate after recurrence of muscle damage. Cellular and molecular regulation of activation and replenishment for satellite cells issues were reviewed. Hoping through the points of nitric oxide-hepatocyte growth factor (NO-HGF), myostatin and Notch signaling and the niche of satellite cells to overcome the recent obstruction in cell therapy in clinic myopathy, such as Duchenne muscle destrophy.

OBJECTIVE: Embryonic Stem Cell (ES) are characterized by totipotency and normal karyotype and provide the theoretical base in the following fields: embryonic developmeut of mammalian, cell differentiation, expres sion of exogenous genes and utilization of Ess to develop animal model for human inherited diseases. The identification of ES therefore is very important to research and utilize ES.DATA SOURCES: The relevant articles to embryonic stem cell between January 1980 and December 2003 were computer searched for in Medline with the key words "embryonic stem cell, embryo, Alkaline phosphatase,Oct-4"in English. Similarly, the relevant articles to embryonic stem cell between January 1980 and December 2003 were computer searched for in China Journal Full-text Database (CJFD) with the key word "embryonic stem cell" in Chinese.STUDY SELECTION: The articles were browsed firstly. The inclusion criteria were for those articles about the identification of embryonic stem cells. The exclusion criteria were for those about repetitive studies, reviews and other similar articles.DATA EXTRACTION: 16 articles about the identification of embryonic stem cells were collected. Then, the full-texts of the articles were looked through.DATA SYNTHESIS: The selected data were summarized in the following order: ①Preliminary identification of Ess based on morphology and growth;②Immunological valuation; ③Chromosome related identification; ④Identi fication of totipotency and pluripotency.CONCLUSION: The identification of embryonic stem cells is not the result of only one identifying method, but a process of identification. During this process of comprehensive identification, it is recommend to conduct AKP test firstly, karyotype analysis secondly, then examination of surface markers and finally identification of Ess totipotency when Ess are sufficient, takingcare to repeat every identification.

Objective To determine the effect of losartan on vascular remodeling and the underlying mechanism in spontaneously hypertensive rats(SHR). Methods SHR of 12 weeks old were given losartan orally [0,15,30 mg/(kg·d),n=12]. The tail arterial pressure was measured every week.Eight weeks later, the pathological changes and p22phox expression in the thoracic aorta, the activity of catalase (CAT), the contents of H2O2 and AngⅡ in the plasma were evaluated. Results Blood pressure was increased in the SHR accompanied by the thickened wall and increased p22phox expression in the thoracic aorta. The plasma levels of H2O2 and AngⅡwere elevated while the CAT level was decreased in the SHR. Administration of losartan reversed the thickened wall and increased the CAT activity concomitantly with the decreased plasma levels of H2O2 and p22phox expression in the SHR. The plasma level of AngⅡincreased after the losartan treatment. Conclusion Oxidative stress induces the vascular remodeling of the aorta in the SHR. Losartan can reverse the vascular remodeling through down-regulating p22phox expression and inhibiting the oxidative stress.