Objective:To investigate the effect of all-trans retinoic acid (ATRA) on the differentiation of marrow stromal stem cells(MSCs)into neurons. Methods: Rat MSCs were expanded as undifferentiated cells in culture for 5-7 passages and pretreated with ATRA for 24 h, then induced by modified neuronal medium (MNM) for 18 h. The control cells were directly cultured in MNM without ATRA pretreatment. Immunocytochemistry was used to detect the expression of nestin, neuron-specific enolase (NSE), neuron-specific nuclear protein (NeuN) and microtuble-associated protein (MAP-2) in the experimental groups and the control cells. The change of cell proliferative cycles and the expression of retinoic acid receptor beta (RAR?) were detected before and after ATRA treatment. Results: 1. The expression of nestin, NSE, NeuN and MAP-2 was much higher than that of the control group. 2. No changes were found in the cell proliferative cycles before and after ATRA treatment. 3. No expression of RAR? was found in MSCs; but positive expression of RAR? was detected afer 24 h of ATRA treatment and it was (20.3?4.2)%. Conclusion: ATRA can activate gene transcription via nuclear receptor RAR? and promote MSCs transdifferentiation into neurons.

Objective To evaluate prospectively the side effects and tolerance of docetaxel with concurrent late-course hyperfractionated radiotherapy after breast-conserving surgery for stage T1-T2 breast cancer, and to assess the value of this treatment in shortening the treatment time and reducing the economic burden among patients. Methods A total of 20 patients with T1-T2 breast cancer were recruited after they underwent breast-conserving surgery. The acute radiation response classification, treatment completion rate, disease-free survival, hospital stays, and treatment costs were observed. Radiotherapy for all patients was started before the last single-agent docetaxel chemotherapy. Results The completion rate of treatment and the good rate of cosmetic effect reached 100%. The main adverse reactions were hematological toxicity (leukopenia) and skin reactions, which were tolerated. The median follow-up time was 30.1 months, and the follow-up rate was 100%. The average total treatment time of this hyperfractionated radiotherapy with concurrent docetaxel was four weeks, and the total hospitalization cost savings was approximately 10, 000 yuan. The 21-month disease-free survival rate was 100%. Conclusion Stage T1-T2 breast cancer can tolerate hyperfractionated radiotherapy with concurrent chemotherapy after a breast-conserving operation. The procedure results in good local control and satisfactory cosmetic effects, with high health and economic value.