BACKGROUND:Mesenchymal stem cel s can differentiate into nerve cel s by chemical induction or co-culture method, but whether mesenchymal stem cel s co-cultured with Schwann cel s differentiate into neuronal-like cel s or Schwann-like cel s is stil controversial.
OBJECTIVE:To explore the inductive role of Schwann cel s derived from rats in the differentiation of human umbilical cord mesenchymal stem cel s.
METHODS:Cocultures of human umbilical cord mesenchymal stem cel s (1×109/L) and Schwann cel s (1×109/L) from neonatal rats were performed using transwel culture dishes. After 2 weeks of cocultures, morphology of the cultured human umbilical cord mesenchymal stem cel s was observed, and the phenotypic changes of cel s were also detected with immumocytochemistry techniques.
RESULTS AND CONCLUSION:After 2 weeks of cocultures, some differentiated cel s showed neuron-like morphology, and expressed nestin, NF-200 andβ-III-tubulin, but did not express Schwann cel special marker S100 and oligodendrocytes special marker MAB1580. These findings indicate that human umbilical cord mesenchymal stem cel s can transdifferentiate into neuronal-like cel s by cocultures with rat’s Schwann cel s.

[Objective]To investigate the etiology,pathological characteristic and therapeutic effect of spontaneous rupture of the finger extensors.[Method]Twelve patients were included in this research group.Eight cases were diagnosed as spontaneous rupture of the extensor pollicis long(EPL) and were repaired by transfer of the extensor indicis proprius(EIP).Three cases were spontaneous double rupture of the the ring and small finger extensors.The distal stump of the ring finger extensor was woven into the middle finger extensor and the EIP was transferred to reconstruct the extensor digiti quinti.There was one case of spontaneous triple rupture of the the middle,ring finger and small finger extensors.Transplantation of frozen allogenic extensors was utilized.[Result]The finger extensor rupture occurred after either rheumatic arthritis or distal radius fracture.The former pathological examination showed that the tenosynovitis and chronic inflammation of tendons accompanying with localized necrosis was dominant,while tendon fiber rupture played an important role in the latter.All patients achieved 100% of good results and no recurrent rupture occurred.[Conclusion]The inflammation invasion or attrition in the fracture site was a patological basis to cause spontaneous rupture of finger extensors.The EPI transposition was a reliable option to reconstruct the EPL.It is suggested that allogenic tendon transplantation be applied in the case of multiple ruptures of the extensor tendons.

Objective To evaluate the long-term effects and safety of an intense pulsed light (IPL) in the treatment of epilation.Methods 159 patients received treatment with a non-coherent IPL because of unwanted facial and body hair.116 cases were followed up by means of phone call or letters.The average follow-up time was 38 months.Results Overall,36 (31.0％) patients were very satisfied,53 (45.7％) were satisfied and 27 (23.3％) remained unsatisfied with the outcome of lightassisted hair removal.The non-coherent intense pulsed light satisfactorily removed unwanted dark hair.Hair-free periods from weeks to years could be observed.Besides,the satisfaction was not related with the colour of the skin.Conclusions Hair removal by a non-coherent intense pulsed light is an effective and safe method for long-term epilation of unwanted hair.

Objective To explore the efficient way to purify and to enrich umbilical cord mesenchymal stem cells which have abilities to differentiate into chondrocytes. Methods Umbilical cord was acquired from new born infants and chopped into 1 mm2 cubics, then they were pretreated with colleganase and trypsin so as to get the mixed cell suspension. CD45(-),CD90(+) cells were acquired from the mixed cell suspension via FCM sorting and were cultured in the medium as umbilical cord mesenchymal stem PO cells. The PO cells were detached and passaged by multiplex collagenase NB4 and the positive rate of CD90 and CD45 of the P1-P3 cells were observeed via FCM ; the P3 cells were induced to differentiated into chondrocytes. Results FCM results showed that the positive rate of CD90 on P1, P2, F3 was (80.86 ± 7.85)%,(95.86± 3.28)%,(97.15± 1.43)%, while the positive rate of CD45 on P1, P2, P3 cells was (2.53 ±0.28)% and (0.97 ± 0.48)% and (0.05 ± 0.01)% respectively; P3 cells had differenciated into chondrocytes. Conclusion FCM presorting and Multiplex collagenase detachment procedures can swiftly acquire highly purified human umbilical cord mesenchymal stem cells which have the ability to differentiate into chondroeytes.

Objective To investigate the effects of labeling Schwann cells with different concentrations of SPIO, and to investigate the feasibility of in vitro MR imaging. Methods The C57BL/6 mices'Schwann cells were isolated, purified, and then 0.5 × 106, 1.0 × 106, 5.0 × 106 cells were labeled with 25.0 μg/ml, 50.0 μg/ml SPIO. Prussian blue stain and transmission electron microscope (TEM) were performed for showing intracellular iron. The signal intensity of cells were evaluated by 3.0 MRI with different sequences in vitro. Results Different cell population (0.5 × 106, 1.0 × 106,5.0 × 106) were cultured with different concentration SPIO about 24 hours. Dyeing degree of labeling cells stained by Prussion blue gradually deepened from 25.0 μg/ml to 50.0 μg/ml. Transmission electron microscope indicated that iron particles accumulated inendosomes/lysosomes. The MR signal intensity of labeling cells were inversely correlated with the concentration of SPIO groups in T2WI and GRE/30° imaging in vitro. Conclusion Schwann cells could be labeled effectively with SPIO, and MRI could be used to monitor these labeled cells in vitro.