BACKGROUND: Recently, several scientists have found that differentiation of neural stem cells (NSCs) towards dopaminergic neurons may be increased in vitro by combination of some special cytokines. They have also found that dopaminergic neurons differentiated from NSCs can be used for the treatment of Parkinsn's disease. To improve the therapeutic effects of/n vitro transplantation, we should further study the biologic characteristics of NSCs at the induction and differentiation.OBJECTIVE: To explore the differentiation of NSCs which were incubated in differentiation solution for different time towards dopaminergic neurons in vitro.DESIGN: Single sample observation.SETTING: Department of Neurosurgery, First Affiliated Hospital of Sun Yat-sen University.MATERIALS: This study was performed at the Department of Ncurosurgery, First Affiliated Hospital of Sun Yat-sen University from May to October 2007. Six healthy Sprague Dawley (SD) rats, gestational age 14 days, of clean grade, weighing 350-400 g,were provided by the Laboratory Animal Center, Sun Yat-sen University[permission No. SCXK (yue)2007-0034]. The protocol was performed in accordance with ethical guidelines for the use and care of animals.METHODS: NSCs derived from rat embryonic mesencephalon were cultured in serum-free culture medium containing epidermal growth factors and basic fibroblast growth factors. After passage, the NSCs were induced to differentiate towards dopaminergic neurons in the differentiation medium supplemented with interleukin 1o, interleukinl 1, human leukaemia inhibitory factors, and glial cell line-derived neurotrophic factors. The percentage of tyrosine hydroxylase positive neurons in differentiated ceils was detected with flow cytometer when NSCs were cultured in differentiation solution for 2, 4, 6, 8 and 10 days, respectively.MAIN OUTCOME MEASURES: Cellular morphological alteration of rat NSCs after differentiation. The percentage of tyrosine hydroxylase positive neurons in differentiated cells derived from NSCs.RESULTS: In differentiation medium, NSC spheres attached the bottom of plates and began to collapse. Cells inside the spheres grew out gradually and became irregular in shape. Six days later, most of the cells had I or 2 long processes and a few short processes. The percentage of tyrosine hydroxylase positive neurons in differentiated cells was respectively (3.2_+_0.9)%, (6.8 +1.6)%, (16.7-+2.6)%, (14.8_+1.8)% and (12.2_+2.5)% after culture for 2, 4, 6, 8 and 10 days, with significant differences (F =26.449, P ＜ 0.05).CONCLUSION: Induction time influences the differentiation of NSCs towards dopaminergic neurons in vitro. The percentage of dopaminergic neurons is the highest in differentiated cells derived from NSCs which are cultured in differentiation solution for 6 days.

Objective To study the application value and safety of sentinel lymph node biopsy ( SLNB) replacing axillary lymph node dissection ( ALND) for patients with early breast cancer .Methods Data was col-lected for patients undergoing SLNB or ALND in the Second Hospital of Dalian Medical University from June 2011 to June 2014.The complication of upper extremity , axillary local recurrence and distant metastasis were retro-spectively analyzed.The patients were followed up to Nov .2014, with the median follow-up of 41 ( 18-52 ) months.Results Patients undergoing SLNB had less postoperative complications of upper extremity ( numb and painχ2 =18.174, P =0.000;Restricted movement χ2 =20.413, P =0.000; Strength loss χ2 =23.785, P =0.000;P<0.05).There was no statistical difference for the postoperative complications of axillary local recur-rence and distant metastasis (χ2 =0.555, P=0.516; P>0.05).Conclusion In early breast cancer without SLN, SLNB can achieve the equivalent effect to ALND with less damage and complications .

Objective To explore the clinical effect of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs) gefitinib combined with platinum-containing chemotherapy and whole brain radiotherapy in the treatment of non-small cell lung cancer (NSCLC) with brain metastasis. Methods One hundred and fifty-six patients of NSCLC with brain metastasis were divided into observation group (82 cases) and control group (74 cases) according to the therapeutic regimens. On basis of whole brain radiotherapy, the patients in control group received platinum-containing chemotherapy (paclitaxel+cis-platinum+pemetrexed), while the patients in observation group received gefitinib. The serum levels of carcino-embryonic antigen (CEA), cytokeratin 19 fragment antigen (CYFRA21-1) and EGFR, short-term effects, progression-free survival (PFS) and incidences of adverse reactions between two groups were evaluated. A subgroup analysis was carried on the 41 cases of patients with EGFR mutant type. The short-term effects and PFS between two groups were compared. Results The levels of CYFRA21-1 and EGFR in observation group were obviously lower than those in control group (P<0.01). The ORR and DCR in observation group was obviously higher than that in control group (81.71％ vs. 36.49％, 93.90％ vs. 82.43％) (P < 0.05 or < 0.01). The median PFS in observation group and control group was 12 months and 6months. There were statistic differences between two groups (P < 0.05). Subgroup analysis showed that the ORR and DCR in observation group was obviously higher than that in control group (72.0％vs. 25.0％, 96.0％vs. 31.25％)(P<0.01). The median PFS in observation group and control group was 13 months and 5 months. There were statistic differences between two groups (P<0.05). There was no statistic difference in incidences of adverse reactions between two groups (P>0.05). Conclusions For patients with NSCLC with brain metastasis, compared with the therapeutic regimen of whole brain radiotherapy + platinum-containing chemotherapy, whole brain radiotherapy + platinum-containing chemotherapy+EGFR-TKIs (gefitinib) could more effectively reduce the levels of EGFR and CYFRA21-1, improve short-term effects, prolong PFS and do not increase the incidence of adverse reactions.