Objective To explore the effects of Neurotrophin-3(NT-3) genetically modified Schwann cells(SCs) on grafted neural stem cell(NSC) differentiation into the neuron-like cells in the transected spinal cord. Methods The NSCs were single-transplanted or co-engrafted with NT-3 modified SCs,report gene LacZ modified SCs,and unmodified SCs respectively into the transected spinal cord 67d later,the differentiation of NSCs was studied by immunohistochemisty,and the percentage of neuron-like cells was calculated. Results NSCs could differentiate into the neuroglial-like cells and neuron-like cells in the injured spinal cord.Compared to the unmodified SCs,NT-3 modified SCs could more efficiently promote NSCs differentiate into the neuron-like cells.The effect of LacZ modified SCs was the same to the unmodified SCs.Conclusion NT-3 modified SCs could promote NSCs differentiate into the neuron-like cells in the injured spinal cord.

Objective To explore the effects of neurotrophin-3 genetically modified Schwann cells(NT-3-SCs) and neural stem cells(NSCs) combinative transplantation to promote the neurons'survival and axonal regeneration of the spinal cord transected rat. Methods After the transected spinal cord injury(SCI) model was established in SD rats,NT-3-SCs or LacZ report gene modified Scwhann cells(LacZ-SCs) were combinative transplanted with NSCs into the transected site.60 days later,fluorogold(FG) was injected into the caudal spinal cord fo the transected site.7days after FG injected,the sacrifice,cryosection and morphology serious studies were performed to observe the FG labeled neurons in the rostral spinal cord(RSC) of transected site,red nuclei(RN) and the sensorimotor cortex(SMC);The survival neurons in the L_1 Clark's nuclei(CN),RN and SMC were couut,and regenerated axons within or near the transected spinal cord observed. Results From more to less,the order of groups of the survival neurons in the CN,RN and SMC was NT-3-SCS & NSCs group,LacZ-SCs & NSCs group,experimental control group.In the NT-3-SCs & NSCs group and LacZ-SCs & NSCs group,there were 5-HT,CGRP and SP positive axons within or near the transected spinal cord.And some FGlabeled cells were found in RSC,RN and SMC. Conclusion Combinative grafting NSCs and NT-3-SCs could promote the neurons'survival and axonal regeneration of the spinal cord injured rat.

10kD fraction from operated side of two groups of animal was tending towards increasing, especially the approximate 67kD protein content from operated side of morphine group of animal.\;

AIM: To explore the effects of neurotrophin-3 (NT-3)-genetically modified Schwann cells (NT-3-SCs) on differentiation of neural stem cells (NSCs) into the neuron-like cells. METHODS: The NSCs were co-cultured with NT-3-SCs. Report gene LacZ genetically modified Schwann cells (LacZ-SCs) and normal SCs respectively in vitro. 7 d later, the differentiation of NSCs was studied by immunohistochemistry, and the percentage of neuron-like cells was calculated. RESULTS: NSCs differentiated to the GFAP-positive cells (glial-like cells) and NF-positive cells (neuron-like cells) in vitro. Compared to the normal SCs, NT-3-SCs more efficiently promoted NSCs to differentiate into the neuron-like cells. The effect of LacZ-SCs was as the same to the normal SCs. CONCLUSION: NT-3-SCs promote NSCs to differentiate into the neuron-like cells. [

Objective To classify and grade the environments with Oncomelania hupensis snails inside embankment in marsh-land and lake areas,so as to improve the work efficiency and realize the systematic management. Methods The schistosomiasis endemic area Liaodi and Xiongdi villages in Jiangling County,Hubei Province were selected as the experiment villages,and the environments with snails in the two villages were divided into sections with a length of 500m,then the snail situation were sur-veyed by the systematic sampling method with 10m and 50m a frame respectively. The environments were classified according to the discovery of infected snails and wild fecal contamination,and the numbers of sites with snails and their areas in different class-es were recorded. Meanwhile,the data of sites with infected snails in Jingzhou City during the recent 5 years were collected and graded according to the average density of snails,so as to discuss the correlativity between the grades of environments with snails and the numbers of sites with infected snails and the occurrence rate of frames with snails. Results There were 1 967 sites with in-fected snails in Jingzhou City during the recent 5 years,and there was a positive correlation between the grades of environments with snails and the occurrence rate of frames with snails(rs=0.77,P<0.01),when the grade was 5,the constituent ratio of num-bers of sites with infected snails was 3.1%,and when the grade was 2-3,the ratio raised to 56.3%. There were 39 sites with snails in the two villages,the Class 1,2 and 3 environments included 1,18 and 20 sites,with the areas of 1 080,51 640 m2 and 41 220 m2 , respectively. There were no statistically significant difference between the grades divided by snail survey with 10m and 50m a frame(χ2=4.667,P>0.05),but the time-consuming of the former was 3 times of the latter. Conclusions The classification and grading of the environments with snails inside embankment in marshland and lake areas can master the key point of the snail survey. The subsection and setting frames at a suitable distance can save time and manpower,improve work efficiency,as well as understand the distribution of snail status of the environment with snails,which can realize the sort management of the snail envi-ronments inside embankment.

After peripheral nerve injury (PNI),myelinated Schwann cells undergo demyelination,dedifferentiation and proliferation,then migrate along basal lamina tubes and align to form the longitudinal cell strands known as bands of Btüngner,which creates suitable conditions for axonal regeneration and remyelination.By reviewing literature,we found that the expression of a transcriptional factor c-Jun increased during demyelination process after PNI,and increasing evidences suggested that demyelination and c-Jun signaling pathways were closely related.This review summarized the research situation and progress of c-Jim signaling pathways regulating demyelination process after peripheral nerve injury.

OBJECTIVETo quantitatively analyze the temporal and spatial pattern of RhoA expression in injured spinal cord of adult mice.

METHODSA spinal cord transection model was established in adult mice. At 1, 3, 7, 14, 28, 56 and 112 days after the surgery, the spinal cords were dissected and cryosectioned for RhoA/NF200, RhoA/GFAP, RhoA/CNPase or RhoA/IBA1 double fluorescent immunohistochemistry to visualize RhoA expressions in the neurons, astrocytes, oligodendrocytes and microglia. The percentages as well as the immunostaining intensities of RhoA-positive cells in the parenchymal cells were quantitatively analyzed.

RESULTSRhoA was weakly expressed in a few neurons and oligodendrocytes in normal spinal cord. After spinal cord injury, the percentage of RhoA-positive cells and RhoA expression intensity in the spinal cord increased and peaked at 7 days post injury (dpi) in neurons, oligodendrocytes and astrocytes, followed by a gradual decrease till reaching a low level at 112 dpi. In the microglia, both the RhoA-positive cells and RhoA expression intensity reached the maximum at 14 dpi and maintained a high level till 112 dpi.

CONCLUSIONTraumatic spinal cord injury can upregulate RhoA expression in the neurons as well as all the glial cells in the spinal cord. RhoA expression patterns vary with post-injury time, location and among different parenchymal cells in the injured spinal cord.

Animals ; Astrocytes ; metabolism ; Female ; Mice ; Mice, Inbred Strains ; Microglia ; metabolism ; Neuroglia ; metabolism ; Neurons ; metabolism ; Spinal Cord ; metabolism ; Spinal Cord Injuries ; metabolism ; rho GTP-Binding Proteins ; metabolism

Objective This study aimed to explore the effect of peripheral blood mesenchymal stem cells combined with porous absorbable gelatin sponge/self assembling peptide composite scaffolds on SD rat femoral con-dyle bone defect reconstruction and provide a new strategy for the repair of bone defects. Methods 30 female SD rats,8W age,were randomly divided into 3 groups,10 every group.The group A was blank control group,group B was porous absorbable gelatin sponge/self assembling peptide composite scaffold group,and group C was periph-eral blood mesenchymal stem cells combined with porous absorbable gelatin sponge/self assembling peptide compos-ite scaffold group. The effect of osteogenesis was observed by paraffin section,hematoxylin eosin staining,X-ray examination,and Micro-CT scanning in 3 dimensional reconstruction of femoral condyle defect. Results Imaging examination showed that the experimental group had better osteogenesis effect. Histological examination showed that a lot of new bone tissue was found in group C,while only a small amount of new bone was found in the group of A and B. Conclusions The experiment shows that peripheral blood mesenchymal stem cells as the seed cells for tissue engineering,combined with porous absorbable gelatin sponge-self assembling peptide has better ability to repair bone defects,and has good application prospect,which is worthy of further research.

Objective To investigate the potential of polylactic acid glycolic acid copolymer (PLGA) composite ordered multi tunnel collagen scaffold in fabricating a biomimetic artificial nerve graft to repair the sciatic nerve defects in rats.Methods The ordered multi tunnel collagen scaffold was prepared by vacuum freeze-drying and directional drawing method to simulate the epineurium;the outer conduit was prepared by PLGA to simulate the epineurium;and then,the ordered multi tunnel collagen scaffolds were loaded in the PLGA conduit (5∶1) under a stereomicroscope to develop a novel biomimetic artificial nerve.Sixty-four rats were randomly divided into four groups:artificial nerve group,PLGA group,peripheral nerve group,and non-graft control group (n=16);rats in the artificial nerve group,PLGA group,and peripheral nerve group were repaired with artificial nerve graft,hollow PLGA conduit and allogeneic sciatic nerve to bridge the sciatic nerve defect,while the sciatic nerve with the gap in rats of the control group was without any grafting.After 11 weeks of operation,the hind limbs of rats in each group were detected by behavioral test,electrophysiological examination and Fluoro-Gold retrograde tracing method.The changes of muscle tissues (gastrocnemius) were observed by hematoxylin staining and TMR-α-BTX staining,and the regenerated axons were observed by immunohistochemical staining with NF200 and the regenerative spinal anterior horn motor neurons were observed by Nissl fluorescence staining 12 weeks after operation.Results After 11 weeks of operation,the recoveries of the motor functions (the distance between the injured hindlimb and forelimb,the rotation angle of the injured foot) in the peripheral nerve group,artificial nerve group,PLGA group and control group were significantly deteriorated in turn,and the differences were statistically significant (P＜0.05).Electrophysiological examination showed that the recovery effect of peripheral nerve group was the best in both latency and amplitude of the compound muscle action potential,followed by artificial nerve group.The latency of PLGA group was the longest and the amplitude of compound action potential was the smallest;significant differences were noted between each two groups (P2＜0.05).At 12 weeks after operation,the wet weight ratio of muscle fibers,area of muscle fibers and neuromuscular junction area were significantly different between each two groups (P＜0.05);the degree of gastrocnemius atrophy in the artificial nerve group was significantly improved than that in the PLGA group,but not yet reached the level of peripheral nerve group.NF200 immunohistochemical staining showed that a large number of NF200-positive axons were seen in the grafts of the artificial nerve group,but the number was slightly smaller than that of the peripheral nerve group;the number of regenerated axons in the PLGA group was the smaller and mainly distributed near the proximal side.In the PLGA group,only (19.33 ±6.73)％ regenerated spinal anterior horn motor neurons were labeled with Fluoro-Gold,while the positive rates of Fluoro-Gold in the artificial nerve group and peripheral nerve group were (42.67±7.45)％ and (50.13±4.33)％;the differences between each two groups were statistically significant (P＜0.05).Conclusion The biomimetic artificial nerve made of PLGA conduit and ordered multi tunnel collagen scaffold can efficiently reconstruct the defected peripheral nerve with guiding axonal regeneration and promoting functional restoration in rats;however,its effect is poor than peripheral nerve grafting.