BACKGROUND:Brain injury is a serious central nervous system trauma.However,it is difficult to promote nerve regeneration and functional recovery after brain injury.Sheath cells are conducive to neuronal survival and axonal regeneration.OBJECTIVE:To explore feasibility and effect of olfactory ensheathing cells transplantation on rat brain injury.METHODS:A total of 90 healthy adult male SD rats were selected and 10 were used to prepare olfactory ensheathing cells.The remaining were randomly divided into model control and transplantation groups with 40 animals in each group.Model of middle cerebral artery occlusion was established by thread method.At 1 week,2×10~6 suspension of olfactory sheath cells and an equal volume of sterile saline were injected into two groups,respectively via the carotid artery.Neurological deficits were evaluated by creeping scores;histopathological changes were detected by HE staining,and glial fibrillary acidic protein and neurotrophic factor receptor p75 expression was detected by immunohistochemistry.RESULTS AND CONCLUSION:Compared with the model control group,the neurological deficit scores were significantly reduced in the transplantation group compared with the control group at 1,2,3,and 4 weeks following cerebral ischemia/reperfusion(P ＜ 0.05);the pathological changes in injured brain tissues were ameliorated,the number of nerve cell degeneration and necrosis was significantly reduced,and edema was attenuated.A great amount of glial fibrillary acidic protein and neurotrophic factor receptor p75 expression was detected in the infarct hemisphere following cell transplantation,and little in the contralateral hemisphere and vascular endothelial cells.Negative expression was detected in the model control group.Results show that the olfactory ensheathing cell transplantation is effective on ischemic brain injury in the rats.

BACKGROUND: Previous research has proved that olfactory ensheathing cells can promote neuronal survival and axonal regeneration. OBJECTIVE: To investigate the effect of olfactory ensheathing cell transplantation on the treatment of spinal cord injury of rats. METHODS: A total of 40 healthy adult female SD rats were randomly divided into control and cell transplantation groups, with 20 rats for each group. Ten additional SD rats were used for separation and culture of olfactory ensheathing cells. Spinal cord injury was induced in both control and cell transplantation groups. 2-cm bilateral 8th-10th intercostal nerves were crossly implanted into spinal cord defect region, i.e., proximal white matter and distal gray matter, distal white matter and proximal gray matter. Olfactory ensheathing cells at density of 2×10~6 were locally injected into cell transplantation group, while an equal amount saline was locally injected into control group. Somatosensory evoked potential and motion evoked potential were detected to observe neuro-electrophsiological recovery; BBB was used to evaluate hindlimb motor function; BDA anterograde tracer was used to observe motor conduction recovery. RESULTS AND CONCLUSION: Latency and amplitude of somatosensory evoked potential and motion evoked potential in the cell transplantation group were significantly greater than control group (P < 0.01). BBB scores of cell transplantation group were significantly greater than control group (P < 0.01). BDA-positive nerve fibers in the cell transplantation group were significantly more than control group (P < 0.01). Local injection of olfactory ensheathing cells can improve neuro-electrophysiological changes and promote hindlimb motor functional recovery following spinal cord injury.

BACKGROUND: To improve neural regeneration and functional recovery following spinal cord injury (SCI) remains difficult. Embryonic neural stem cells benefit neuronal survival and promote axonal regeneration.OBJECTIVE: To explore the feasibility of the local injection of embryonic neural stem cells to treat rats with high level SCI, and evaluate its effect by neuroelectrophysiology and motor function of hind limbs.DESIGN, TIME AND SETTING: In vivo experiment of cytology was performed at the Animal Experimental Center of Harbin Medical University from June 2007 to June 2008.MATERIALS: A total of 40 healthy adult SD rats were randomly divided into two groups (n=20): normal saline and cell transplantation groups. In addition, 5 SD rats, pregnant 14 days, were used for preparation of embryonic neural stem cells.METHODS: High level SCI was made in two groups. Briefly, 2 cm of bilateral intercostal nerves respectively from the 8~(th) to 10~(th) costal bones was crossing implanted in the SCI (proximal white matter and distal gray matter; distal white matter and proximal gray matter). Cell transplantation group was locally injected with 2×10~6 embryonic neural stem cells, and normal saline group was injected with the same volume of normal saline.MAIN OUTCOME MEASURES: Somatosensory evoked potential (SEP) and motor evoked potentials (MEP) testing, observation of the recovery of neuroelectrophysiology; BDA anterograde neural tracer; the recovery of motor conduction by the main beam;BBB hind limb motor function score.RESULTS: SEP and MEP latency and amplitude of cell transplantation group were better than normal saline group (P < 0.01).BDA-positive nerve fibers through the tag were found in cell transplantation group, but no in normal saline group. BBB hind limb motor function score of cell transplantation group was significantly improved compared with normal saline group improved (P < 0.01).CONCLUSION: Local injection of embryonic neural stem cells betters neuroelectrophysiology and motor function of hind limbs following high level SCI.

Objective:To explored the mechanisms that lead to the changes of the memory T cell subsets.Methods:By using of flow cytometry and enzyme-linked immunosorbent assay(ELISA), we detected the percentage of memory T cell subsets and plasma concentration of interleukin-15(IL-15) in peripheral blood of MS patients and healthy individuals. Furthermore, MS patients were subdivided into both relapse-remission MS(RRMS) and chronic progressive MS(CPMS) group according to the clinical features.Results:Compared to healthy controls, there was an increase and decrease in CD8~+T_ CM and terminal effector memory CD8~+T cell in MS patients(P

0.05).Conclusion:The decrease in 4-1BB expression,rather than the GITR expression,on CD4+CD25high T cells of MS patients suggests that 4-1BB may be involved in the lower immunoactivity of the cell population,while the GITR may play a minor or fine role in the immunoregulation of the cells.

Objective To develop a synthetic medical image generation system which can provide test images for the validation of medical image segmentation algorithms.Methods The synthetic image was created based on the deformation of region of interest (ROI) in original clinical images.First the synthetic foreground boundarywas generated by the resampling of the Fourier descriptors of manually segmented foreground boundary in original image.Then all the ROI pixels were divided into 4 categories and their intensities were calculated by texture matching techniques.Results The intracranial hemorrhage image was selected as the original image,and the generated synthetic images were applied to validate the precision and accuracy of multi-threshold segmentation and level set algorithm.Conclusion The proposed system can rapidly generate synthetic images with realistic appearance of clinical cases and well define ground truth foreground boundary.It has strong practicality for quantitative validation of segmentation algorithms.

Objective To study the immune function of the subpopulation of T helper lymphocyte(Th), including Th1 and Th2 cells in myasthenic thymus and peripheral blood (PB).Methods Enzyme-linked immunospot (ELISPOT) method is adopted to detect the acetylcholine receptor (AChR)-reactive interleukin-2(IL-2)-, interleukin-4 (IL-4)-, interleukin-10 (IL-10)-, interferon-gamma(IFN-?)-secreting cell numbers in thymus and peripheral blood (PB). Results The AChR-reactive IL-2-,IL-4-,IL-10-, IFN-?-secreting cell numbers were increased in thymus as well as the AChR-reactive IL-10-, IFN-?-secreting cell numbers in PB. There is a positive correlation between thymus and PB in MG for the AChR-reactive IL-4-, IL-10-secreting cell numbers. After treatment, the AChR-reactive IL-2-,IL-4-, IFN-?-secreting cell numbers were decreased in PB, while there were 1 case and 2 cases showing a decrease and an increase in AChR-reactive IL-10-secreting cell number, respectively.Conclusions The immune dysfunction of the Th1 and Th2 subpopulation existed in the thymus and PB of MG, and the AChR-reactive IL-4-, IL-10-secreting cell numbers might be served as parameters to evaluate the degree of the immune dysfunction in the MG thymus. The role of the IL-10 in pathogenesis of MG needs further study.

Objective To research the location in cerebral circulations of recurrent stroke.Methods We included patients with acute cerebral infarction from the Department of Neurology of People's Hospital of Peking University within three years.We followed up the patients by telephone and electronic medical record to determine whether they belong to recurrent group or not.We recorded the clinical and image variables of recurrent group.We classified the recurrent group by whether the loci of recurrent stroke is in the same circulation.We determined the independent risk factors of the same circulation loci by Cox regression.Results There are 106 cases of recurrent stroke.Within 5 years,46.2％ of the cases had recurrent loci in the same circulation as first stroke loci.53.8％ of the cases had recurrent loci in the different circulation from first stroke loci.According to logistic regression,whether the recurrent loci was in the same circulation was not related to age,sex,hypertension,diabetes mellitus,smoking,but related to the survival time.The shorter the survival time was the more ratio of same circulation loci happened.The longer the survival time was the more ratio of different circulation loci happened.37％ of cases with recurrent strokes happened in the first year occupied the most cases in the 5 years.Conclusions With the long time study of the location of recurrent stroke,we get the conclusion that the longer the survival time is the more ratio of different circulation stroke happen.So we emphasize the importance of medicine for the stroke in long time.At the same time we conclude the rationality of endovascular treatments within 1 year from first stroke because recurrent loci is more often in the same circulation in 1 year.

Objective To obtain recombinant human stanniocalcin 1 ( STC1 ) with biological activity in Escheri.coli cells expression.Methods The gene was cloned into pET32b( +) vector by fused with thioredoxin and His tag .E.coli BL21(DE3) competent cells were transfomed by the recombinant vector .After renaturation, the fusion protein was digested with thrombin and intact STC1 protein was purified from the digested protein using Ni ion affinity chromatography .Recombi-nant humanSTC1 protein was confirmed by Western blot analysis using goat anti-STC1 antibody.The biological activity of STC1 in rat was assayed using standard method for assessment of renal function .Results The recombinant human STC 1 fu-sion protein is successfully expressed in Escherichia coli, the fusion protein was purified by affinity chromatography from the inclusion body and renaturated .Intact hSTC1 protein was released by thrombin digestion and purified by Ni ion affinity col-umn.The intact STC1 proteins was confirmed by Western blot analysis .Rat bioassay revealed that STC1 boosted phosphate reabsorption.Conclusion Recombinant STC1 protein was successfully expressed and has native biological activities .This protein could be used as an antigen for the preparation of monoclonal antibody against humanSTC 1.

Objective To construct anti-IL-4R murine anti-human single-chain variable fragment (scFvs) antibodies through BL21 (DE3) prokaryotic expression system. Methods The anti-IL-4R scFv sequence was optimizated on the basis of previous findings. The optimized scFv sequence was analyzed. The recombinant plasmid pET-32a-scFv was constructed. The recombinant plasmid was detected through enzyme identification, and was turned into BL21 (DE3) prokaryotic expression bacteria to express the pET-32a-scFv recombinant protein in E.coli BL21 (DE3). The purification and renaturation were researched, and SDS-PAGE analysis was studied. The molecular weight of ScFv against IL-4R was analyzed by SDS-PAGE. The expression of the fusion protein was detected by Western-blot assay. Results The length of fusion gene scFv-MLT sequence was 761 bp. The molecular weight of the recombinant expression of proteins of anti-IL-4R single antibody was approximately 45 ku. The recombinant proteins showed high specificity with anti-6 × His-tag antibody. Conclusion This experiment successfully constructs pET-32a-scFv prokaryotic expression system of recombinant protein with high immune reactivity, which provides the basis for further study of anti-IL-4R single chain antibody as drug target.