BACKGROUND: The glial scar formation after spinal cord injury in mammals is the physical and chemical barriers for neural regeneration, and relieving or delaying glial scar formation can provide benefit conditions for the regeneration of injured spinal cord.OBJECTIVE: To design and screen short hairpin RNA (shRNA) interfere molecular targeting the gene coding region of glial fibrillary acidic protein (GFAP) in rat, and reconstruct the eukaryotic vector of shRNA.DESIGN: An observational animal experiment.SETTING: Department of Spine Surgery, Shenzhen Hospital affiliated to Southern Medical University.MATERIALS: Twenty-five Wistar rats of clean degree, either male or female, weighing 20-25 g, were used. DMEM/F12,lipofectamine2000, Trizol RNA separating kits); fetal bovine serum (Hyclone); BamH Ⅰ, HindⅢ, Pstl, Sail and T4 ligases;Plasmid mini preparation kit and DNA gel extraction kit.METHODS: The experiments were carried out in the Shenzhen Hospital affiliated to Southern Medical University from October 2005 to June 2006. Three pairs of shRNA template which composed of 19 bp reverse repeated motif of GFAP target sequence with 9 bp spacer were designed and synthesized, then they were inserted directionally into plasmid Psilencer 2.1 respectively to generate small interfering RNA (siRNA) eukaryotic expression vector. ShRNA molecules were transfected by liposome via ex vivo expression repressive model of GFAP of rat spinal astrocytes. The effects of expressive suppression were detected with real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, and then the optimal shRNA eukaryotic vector of repressive expression of GFAP was screened.MAIN OUTCOME MEASURES: ① Interfering sequence specific shRNA template synthesis; ② Constructing specific recombinant plasmid eukaryotic expression vector. ③ Culturing rat spinal astrocytes in vitro; ④ Effects of expressive suppression on GFAP in primary astrocytes after RNA interference detected with real-time fluorescence quantitative RT-PCR and Western blot.RESULTS: Sequence analysis showed that GFAP-shRNA recombinant plasmid eukaryotic expression vector was successfully constructed, and optimal GFAP-shRNA eukaryotic vector was screened using real-time fluorescence quantitative RT-PCR and Western blot. The GFAP expressions were reduced by 81%, 63% and 56% at the levels of mRNA and protein respectively.CONCLUSION: GFAP-shRNA eukaryotic expression vectors were successfully constructed and screened. The gene expression GFAP of primitive rat astrocyte can be suppressed significantly by the GFAP-shRNA eukaryotic expression recombinant optimized via ex vivo cellular expression suppression model, which should pave the way for the following multiple targets of RNAi genetic manipulation in the treatment of suppression of glial scar formation after spinal cord injury.

To study the effects of major components of Maijunan tablets, puerarin (Pue) and rhynchophylline (Rhy) on the transport of hydrochlorothiazide (Hct) Caco-2 cell monolayer model, the transport parameters of Hct, such as apparent permeability coefficient (P(app) (B --> A) and P(app) (A --> B)) and the ratio of P(app) (B --> A) versus P(app) (A --> B), were studied and compared when Hct was used solely and co-used with Pue and/or Rhy. The effects of drug concentrations, conveying times, P-glyprotein (P-gp) inhibitor verapamil and conveying Liq pH values on the transport of Hct in the above conditions were also investigated. The results indicated that the absorption of Hct in Caco-2 cell monolayer model could be a carrier-mediated active transport, along with the excretion action mediated by P-gp. Pue can decrease the excretion action of Hct mediated by P-gp, and Rhy had no significant effect on the transport of Hct. The co-use of Hct, Pue and Rhy enhanced the absorption of Hct. Meanwhile, conveying Liq pH value had significant influence on the transport of Hct. The absorption of Hct at pH 6.0 was higher than that at pH 7.4.

AIM: To investigate whether three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) can be used as a reliable screening tool for evaluation of intracranial vascular stenosis and occlusive disease before stent implantation. METHODS: Thirty-three patients with suspected intracranial arterial stenosis received 3D TOF MRA and digital subtraction angiography (DSA) examinations in Chaoyang Hospital Affiliated to Capital Medical University between March 2007 and April 2008,and were included for this study. Two physicians blindly estimated stenosis,patient history,and clinical information of 363 vascular segments from 33 patients,including bilateral internal carotid artery (ICA),anterior cerebral artery (ACA),middle cerebral artery (MCA),posterior cerebral artery (PCA),vertebral artery,and basilar artery (BA). Stenosis was categorized as 30%-49%,50%-69%,70%-99%,and 100%. For each kind of stenosis,sensitivity,specificity,positive predictive value,negative predictive value,K and P values of MRA were calculated,respectively,as compared to DSA. RESULTS: A total of 42 diseased vascular segments were identified. Compared to DSA,for intracranial stenosis 50%-69%,3D TOF MRA showed sensitivity 100%,specificity 96.8%,positive predictive value 62.1%,negative predictive value 100%,K value 0.751,and P value 0.000; For intracranial stenosis 70%-99%,the corresponding value was 100%,98.6%,70.6%,100%,0.821,and 0.000,respectively; For intracranial stenosis 30%-49%,it was 25.0%,99.7%,66.7%,98.3%,0.356,and 0.000,respectively.CONCLUSION: For high sensitivity and specificity to intracranial stenosis 100%,70%-99%,or 50%-69%,compared to DSA,3D TOF MRA is a reliable screening tool for preoperational evaluation of intracranial vascular stenosis and occlusive disease.

BACKGROUND: It is demonstrated that bone marrow stem cells (BMSCs) can generate neurosphere structures, which is similar to cloning sphere of neuron-specific enolase (NSE), in a specially induced system in vitro; therefore, BMSCs draw more and more attention as seed cells to repair central nerve injury.OBJECTIVE: To investigate the differentiation from BMSCs into neuron-like calls induced by fetal spinal cord tissue.DESIGN: Observational study.SETTING: Department of Spine Surgery, Second People's Hospital of Shenzhen.MATERIALS: SD rats (16 pregnant days old and 2 months old) were provided by Animal Center, Tongji Medical College,Huazhong University of Science and Technology. Single antibody of NSE, multi-antibody of glial fibrillary acidic protein (GFAP) and single antibody of neurofilament (NF200) were provided by Wuhan Boster Company.METHODS: The experiment was carried out in Immune Opening Laboratory and Central Laboratory, Basic Medical Department, Tongji Medical College, Huazhong University of Science and Technology in September 2006. Bones of lower extremities of rats were collected to centrifuge BMSCs. Fetal spinal cord tissue homogenate was extracted from 16 pregnant days old rats to make inducing solution and induce differentiation of BMSCs. Otherwise, embryo muscle tissue was used to make muscle tissue homogenate as the same way so as to regard as the controls.MAIN OUTCOME MEASURES: BMSCs underwent morphological observation after induction; in addition, anti-NSE, NF200 and anti-GFAP were used to label neurons and astrocytes, respectively. Ten non-overlapping sights were randomly selected from positive reactive-induced cells after immunohistochemical staining under optic microscope to calculate ratio of positive cells of NSE and NF200 counting for total numbers of cells.RESULTS: ① Morphological changes of BMSCs after induction: During early induction, optic microscope indicated that soma of partial cells rebounded; whose apophysis was long and thin; apophysis of differentiated cells grew gradually and intercrossed each other. It was similar to nerve cells and some branches were similar to dendrite branches. However,morphological changes of cells in the control group were not obvious. ② Expression of relevant antigens differentiated from BMSCs into neuron-like cells at one week after induction: Most cells in spinal cord homogenate group expressed as positive NSE and NF200; a few of cells expressed as GFAP. While, positive staining of nerve cell antibody was not observed in the control group; meanwhile, positive reaction of nerve cell antigen was not observed in the control group,too. Immunohistochemistry examination demonstrated that positive rates of NSE and NF200 expressions were (68±1.7)%and (76.2±2.9)%, respectively.CONCLUSION: Fetal spinal cord tissue homogenate can induce differentiation from BMSCs into neuron-like cells.

BACKGROUND:Recently, non-fusion technology representing as artificial cervical disc replacement continues to improve. On the basis of reconstruction of disc structure and function of involved segments, cervical spine structure of surgery area segment is significantly close to dynamic and static load stress distribution required by natural physiological systems. It effects are apparent in protecting intervertebral facet joints of degenerated segment and structure and function of the cervical spine of adjacent segments and in maintaining cervical dynamic stability, which presented obvious methodological strengths compared with segmental fusion technology.
OBJECTIVE:To evaluate the clinical outcomes of anterior cervical discectomy and fusion and Bryan artificial cervical disc replacement in the treatment of single-level cervical spondylotic myelopathy or radiculopathy.
METHODS:A total of 43 middle and old age patients with single-level cervical spondylotic myelopathy or radiculopathy, who were treated from March 2010 to March 2012, were enrol ed in this study. They were randomly assigned to anterior cervical discectomy and fusion group (fusion group) and Bryan artificial cervical disc replacement group. Range-of-motion of cervical overal and adjacent intervertebral area near the intervertebral space was observed with radiography. During fol ow-up, postoperative recovery of neurological function was evaluated using Japanese Orthopaedic Association scale, visual analog scale and neck disability index.
RESULTS AND CONCLUSION:None patients experienced complications of neurovascular injury during and after the surgery. Range-of-motion of postoperative overal cervical vertebra and adjacent joint was improved in the Bryan artificial cervical disc replacement group compared with the fusion group. Neurological function was apparently improved after surgery in each group. At 3 months after surgery, scores of Japanese Orthopaedic Association, visual analog scale and neck disability index were significantly improved in the Bryan artificial cervical disc replacement group compared with the fusion group (P<0.05). During final fol ow-up, there were significant differences in visual analog scale scores between the two groups. Japanese Orthopaedic Association scale score and neck disability index score were similar between the two groups. During fol ow-up, no prosthesis sinking, displacement or heterotopic ossification were detected. These data indicated that artificial cervical disc replacement could effectively keep the range of motion of cervical segments and protect disc degeneration of adjacent segment. Mid-term fol ow up obtained similar improvement of neurological function of fusion surgery. The moderate-term and short-term efficacies of non-fusion technology were better than fusion technology in the treatment of single-level cervical spondylopathy.

BACKGROUND: Pathophysiological mechanism of local microenvironment is complex after central nerve injury; especially,both inflammatory reaction at an acute phase and formation of secondary glial scar have tremendous effects on effective regeneration of axon, regeneration and arrangement of local nerve cells, proliferation and migration of local stem cells;therefore, it becomes a basic reason for blocking nerve repair in an early period. Thus, how to effectively resist inflammatory factors in injured region at an acute phase and how to optimize microenvironment of neural regeneration are the most important strategies for repairing spinal cord injury in recent years.OBJECTIVE: To design, establish and screen the best expression of interleukin-6 receptor (IL-6R) α to inhibit shRNA adenovirus expression vector by using spinal cord injury models.DESIGN: Duplicative measurement study.SETTING: Department of Spine Surgery, the Second People's Hospital of Shenzhen.MATERIALS: A total of 40 healthy Wistar rats, either gender, 8-10 weeks old, were selected in this study. Rabbit-anti-rat glial fibrillary acidic protein (GFAP) antibody Ⅰ was provided by Santa Cruz Compan; siRNA eukaryon expression plasmid pGenesil (cohtaining green fluorescent expression system) was provided by Wuhan Jingsai Bioengineering Company.METHODS: The experiment was carried out in ImmuneOpening Laboratory, Basic Medical Faulty, Tongji Medical College, Huazhong University of Science and Technology, and Medica Laboratory Center, the Second People's Hospital of Shenzhen in November 2006. Three pairs of shRNA template which composed of 19 bp reverse repeated motif of IL-6 receptor (IL-6R) α target sequence with 9 bp spacer were designed and synthesized, then the recombinant adenovirus expression vectors with green fluorescence protein were constructed in vitro respectively. The acute spinal cord injury models were completed, and the adenovirus recombinants were regionally injected post 12 hours after spinal cord injury;in addition, the inhibitory effect of RNA interference (RNAi) on expression of IL-6R in local region after spinal cord injury were detected by using real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot so as to screen adenovirus expression vector which had the best inhibitory effect on expression of IL-6R.MAIN OUTCOME MEASURES: Inhibitory effect of RNAi on expressions of IL-6R RNA and protein in local region after spinal cord injury.RESULTS: Sequence analysis showed that IL-6R-shRNA recombinant adenovirus expression vector was successfully constructed, and optimal IL-6R-shRNA recombinant adenovirus expression vector was screened by using real-time fluorescence quantitative RT-PCR and Western blot. The IL-6R expressions were 49% and 56% at the levels of mRNA and protein, respectively.CONCLUSION: The IL-6R--shRNA recombinant adenovirus expression vector is successfully constructed and screened.The gene expression of IL-6R can be highly inhibited after acute spinal cord injury.

BACKGROUND: Glial cell-derived neurotrophic factor (GDNF) and transforming growth factor-beta 1 (TGF-β1)co-subordinate to TGF-β family. Both of them play very important roles in the development and differentiation of central and peripheral nervous system, and regulation of cell cycle in mammals.OBJECTIVE: To observe the differentiation of spinal cord-derived neural stem cells(NSCs) induced by GDNF combined with TGF-β1, and make a comparison of differentiation results with GDNF or TGF-β1 culture fluid.DESIGN: Controlled observation.SETTING: Central Laboratory, Shenzhen Hospital Affiliated to Southern Medical University.MATERIALS: Ten SD rats of clean grade, which were at conception for 16 days, were provided by the Experimental Animal Center, Tongji Medical College, Huazhong University of Science and Technplogy. Main reagents and materials:DMEM/F12,B27(GIBCO); basic fibroblast growth factor (bFGF), GDNF; TGF-β1(PeproTech);fetal bovine serum (FBS,Hyclone); nestin multiple antibody (Boster, Wuhan); glial fibrillary acidic protein (GFAP) multiple antibody; neurofilament protein (NF-200) monoclonal antibody (Sigma).METHODS: This experiment was carried out in the Central Laboratory, Shenzhen Hospital Affiliated to Southern Medcial University between October 2005 and September 2006. Under the aseptic condition, rat fetus was isolated for isolation and culture of spinal cord-derived neural stem cells. In this study, five groups were divided: basal medium group, control group, bFGF group, TGF-β1 group, GDNF+ TGF-β1 group. In the basal medium group, DMEM/F12 containing penicillin,streptomycin, amphotericin (AMPH) B and 0.02 volume fraction of B27 annex solution. At 1 week after primary culture, rat spinal cord-derived NSC clones proliferated in vitro stably were harvested. In the control group, 0.1 volume fraction of FBS was added into basal medium. In the later three groups, induced medium was exchanged, i.e. 20 μg/L bFGF, 2 μg/L TGF-β1, and 10 μg/L GDNF+2 μg/L TGF-β1 were added into the basal medium, respectively. ①The differentiation of spinal cord-derived NSCs induced by different factors were observed under the optical microscope. ②The expressions of neurons and astrocytes were detected by immunocytochemical staining labeling. ③ The differentiated cells were counted by sorting technique by means of fluorescence excitation flow cytometer, and the percentage of NSCs differentiating into neurons and astrocytes were detected under the different induction environments.MAIN OUTCOME MEASURES: ① Morphological feature of cell differentiation in each group. ② Immunohistochemical detection of NSCs in each group. ③ The percentage of NSCs differentiating into neurons and astrocytes in each group.RESULTS: ① Cell morphology during differentiation: At the early stage of differentiation, lots of cells creeped to all the directions, and one week later, most of the migrated cells adhered to the wall entirely. Neuron-like cells, astrocyte-like cells and oligodendrocyte-like cells could be identified in the low-density cell region. ②Immunohistochemical detection results: A lot of GFAP- positive astrocytes were found in the control group and TGF-β1 group; Many differentiated neurons and NF-200 staining positive were found in the bFGF group and GDNF+ TGF-β1 group. ③Percentage of stained neuron and astrocyte: at one week of induction, the percentage of stained neurons was higher in the GDNF+ TGF-β1 group than in the control group, bFGF group and TGF-β1 group (x2=24.15,19.56,25.32,P ＜ 0.05-0.01), and the percentage of stained astrocytes was lower in the GDNF+ TGF-β1 group than in the control group, bFGF group and TGF-β1 group (x2=24.45,23.79,P ＜ 0.01 ).CONCLUSION: The combined in vitro induction of GDNF and TGF-β1 contributes to the neuronal differentiation of spinal cord-derived NSCs, indicating that both of them have synergistic effect.

Objective To explore the changes of susceptibility of different sides and gender in healthy young adults with quantitative susceptibility mapping (QSM).Methods Totally 41 healthy young right-handed adults underwent conventional brain MRI and QSM scan,and the susceptibility maps were obtained by the image post-processing software.Then the ROI of the bilateral frontal grey matter (FGM),frontal white matter (FWM),caudate (CA),globus pallidus (GP),putamen (PU),thalamus (TH),substantia nigra (SN),red nucleus (RN),dentate nucleus (DN),pons (PO),corpus callosum (CC) were manually drawn to obtain magnetic susceptibility on the susceptibility map.The magnetic susceptibility of each ROI was compare between both sides,as well as gender by Mann-Whitney test.Results The magnetic susceptibility of the bilateral ROI of GP was the highest,and SN was followed,FWM was minimum.The susceptibility of bilateral FGM,FWM,CA,GP,PU,TH,SN,RN,DN,PO,CC had no statistically significant differences (all P＞0.05).The magnetic susceptibility in CA of different gender had statistically significant difference (P＜0.05).Conclusion The brain magnetic susceptibility.can be measured by QSM,and it can assess brain iron content quantitatively.

Objective To study the protective effect of glucocorticoid preconditioning on the myocardial ischemic and reperfused hearts.Methods Totally 18 rabbits were randomly divided into three groups: myocardial ischemia-reperfusion model(model),high-dose glucocorticoid given by one time group(high-dose group) and low-dose glucocorticoid given by several times group(low-dose group),with six rabbits in each group.Myocardial ischemia was induced by left anterior descending coronary artery ligation.ST segments were recorded by the BL-420 biological signal acquisition system.Plasma malondial dehyde(MDA) was examined before ischemia,at 15 min after ischemia and 30 min after reperfusion;ischemic heart muscles were prepared with cryotomy and stained histochemically.Succinic dehydrogenase activity was observed in the ischemic region.Results There was shorter time of ST-segment recovery in the high-dose group and the low-dose group than that in the model group.Serum level of MDA in the high-dose group was lower than in the low-dose group(P

Objective To summarize the clinical and imaging characteristics of Rosai-Dorfman disease (RDD) in order to improve the diagnosis of the disease.Methods The clinical and imaging features of 10 patients with RDD proved by pathology were retrospectively analyzed and the related literatures were reviewed.Results Ten patients including 7 males and 3 females,aged 8 to 54 years old,with average of 32 years old.White blood cells (BCA) and erythrocyte sedimentation rate (ESR) in 8 cases were normal.Eight cases manifested as painless enlarged lymph node or mass,of which 4 cases were accompanied with multisystem involvement.Three lesions involved lymph nodes,5 lesions were located in extranodal sites,while 2 lesions involved both lymph node and extranodal sites.RDD occurred in lymph nodes (n=3) manifested as multiple enlarged lymph nodes on CT imaging,showing mild or moderate the enhancement,or a heterogeneous ring-enhancement.Of 5 extranodal RDD lesions,3 cases underwent MR exmination.2 lesions manifested as subcutaneous soft tissue mass on left shoulder and anterior abdominal wall,1 lesion manifested as intracranial mass accompany with localised cranial bone destruction.Lesions in all 3 cases had poor margins and showed scatted areas of high signal on diffusion weighted images.Lesions exhibited remarkable heterogeneous enhancement on Gd-DTPA enhanced MR imaging,dural/fascia tail sign and dilated blood vessels could be found around the lesions.Intrahepatic RDD lesion showed fast washing out phenomenon on CT enhanced imaging.In 2 cases involved both lymph node and extranodal sites,1 case manifested as swelling pharyngeal lymph chain and nasopharynx,enlargement of lymph nodes in bilateral submandibular and cervical region abdominal cavity on CT imaging,the enhancement is mild and moderate,accompany with osteolytic lesions in right proximal humerus on X-ray.For the other case,CT images manifested as bilateral neck lymphadenopathy,accompanied with soft tissue mass in nasal cavity,the lesion showed mild/moderate enhancement.Conclusions RDD mostly appears in young and middle-aged men,and is rarely preoperatively diagnosed.RDD mainly manifests as painless enlarged lymph node or mass.RDD has a broad spectrum of radiographic appearance,varied according to different location of lesion.Scatted higher signal areas on diffusion weighted images in the masses and significantly heterogeneity enhancement with dilated blood vessels around the lesion could be helpful in diagnosing of extranodal RDD.