Effect of different immunization schedules on diphtheria antibody level among preschool children in Shenzhen / 中国学校卫生

Objective@#To evaluate the immunity and influencing factors of diphtheria among preschool children in Shenzhen,to provide reference for effective monitoring of diphtheria IgG antibody level in preschool children.@*Methods@#Serum samples were collected from 296 preschool children aged 4-6 who were recruited in Shenzhen. The diphtheria antibody titer in serum was determined by enzyme linked immunosorbent assay, and the effect of different immumuzation schedule including types of vaccine and vaccination timing, on the geometric mean concentration (GMC) of diphtheria IgG antibody and antibody positive rate were analyzed.@*Results@#The GMC of diphtheria IgG antibody was 0.71 IU/mL, and the positive conversion rate was 33.1%. There were significant differences in antibody GMC and antibody positive conversion rate of diphtheria in different age groups( F/χ 2=11.77, 27.45, P < 0.01 ). The GMC and antibody positive conversion rate showed significant differences by diphtheria antibodies, vaccine types and end dose vaccination intervals( F=49.53, 12.95，11.61, P <0.01). There were statistically significant differences in the positive conversion rate of diphtheria antibodies in children with different types of diphtheria antibodies, vaccine types of diphtheria antibodies, and diphtheria antibodies at the time interval of final vaccination (Fisher exact probability method, P <0.01).@*Conclusion@#The overall positive conversion rate of diphtheria antibody in preschool children in Shenzhen is high. Timely completion of full diphtheria vaccination can improve the antibody level and plays a better role in protecting preschool children.

Progress in prevention and control of Nipah virus disease / 中华流行病学杂志

Nipah virus disease (NVD) is a newly emerged zoonosis with a case fatality rate of 40%-75%. NVD is a severe threat to human health and the development of livestock farming. NVD has become one of the emerging infectious diseases with great concern globally during more than 20 years. Nipah virus (NiV) is a pathogen for NVD, the natural host of which is Fruit bats of the Pteropodidae family. The clinical spectrum of NiV infection is broad, including asymptomatic infection, acute respiratory infection, fatal encephalitis, and even death. Since NiV was first identified in Malaysia in 1999, it has been prevalent mainly in Southeast Asia and South Asia. NiV is primarily transmitted to humans through bat-pig-human, contaminated food. Currently, there are no specific therapeutic drugs and vaccines for NVD. Although there are no cases of NVD reported in China, which has close personnel and trade exchanges with major NVD-endemic countries, and NiV antibody has also been detected in relevant bats. There is a potential risk of importing NVD and domestic outbreaks in the future in this country. This paper provides a systematic review of the research progress in the prevention and control of NVD etiology, epidemiology, clinical manifestations and laboratory diagnosis to help relevant staff to understand NVD more comprehensively and systematically.

Changes of T lymphocyte subset levels in peripheral blood of acute myeloid leukemia patients and the clinical significance / 第二军医大学学报

Objective To detect the changes of T lymphocyte subset levels in peripheral blood of acute myeloid leukemia (AML) patients and explore the clinical significance. Methods Total of 68 newly diagnosed AML patients and 76 healthy candidates (healthy controls) were selected for the study. Prognostic risk stratification of AML patients was stratified according to Chinese guidelines for diagnosis and treatment of adult AML (not acute promyelocytic leukemia) (2017). The enrolled patients were divided into high-risk group (20 cases) and non-high-risk group (48 cases). The curative effect of AML patients was evaluated after standard chemotherapy. The flow cytometry technique was used to detect T lymphocyte subset levels in peripheral blood of the AML patients and the healthy controls. Results Proportions of CD3+, CD4+T cells as well as CD4+/CD8+ ratio in AML group were significantly lower than those in healthy controls (all P<0.05), but the proportion of regulatory T (Treg) cells was significantly higher than that in healthy controls (P<0.05). The proportions of CD3+, CD4+T cells and CD4+/CD8+ ratio in high-risk patients were significantly lower than those in non-high-risk patients (all P<0.05). The proportion of Treg cells in high-risk patients was significantly higher than that in non-high-risk patients (P<0.05). The proportions of CD3+, CD4+T cells and CD4+/CD8+ ratio in patients who achieved complete remission (CR) (n=41) were significantly higher than those in patients without CR (n=27) (all P<0.05). However, the proportion of Treg cells in AMLCR patients was significantly lower than that in patients without CR (P<0.05). Conclusion Observation of T //////lymphocyte subsets and CD4+/CD8+ ratio can benefit to disease monitoring of patients with AML..

Single-level lumbar pyogenic spondylodiscitis treated with minimally invasive anterior debridement and fusion combined with posterior fixation via Wiltse approach / 华中科技大学学报（医学）（英德文版）

The effect and safety of anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach were assessed in the single-level lumbar pyogenic spondylodiscitis. Seventeen patients from 2007 to 2009 underwent anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach. Postoperative follow-up time was 24-41 months. Data included the patients' general information, microbiology, operative time, intraoperative blood loss, postoperative complications, intervertebral fusion rate, and preoperative and final follow-up scores for American Spinal Injury Association (ASIA) impairment, visual analogue scale (VAS), and Oswestry Disability Index (ODI). Ten patients had undergone a prior spinal invasive procedure, and 7 had hematogenous infection. The infected segments included L1-2, L2-3, L3-4, and L4-5 in 1, 2, 5, and 9 cases, respectively. Thirteen bacterial cultures were positive for Staphylococcus aureus (5 cases), Staphylococcus epidermidis (4), Streptococcus (3), and Escherichia coli (1). The operative time was 213.8±45.6 min, and the intraoperative blood loss was 180.6±88.1 mL. Postoperative complications consisted of urinary retention (2 cases), constipation (3), and deep vein thrombosis (2). On the final follow-up, VAS scores and ODIs were significantly lower than those of preoperation, while the ASIA grades improved. All the cases achieved good intervertebral bony fusion. Anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach can successfully treat single-level lumbar pyogenic spondylodiscitis, with less trauma and reliable immobilization. It is a viable option for clinical application.

Single-level lumbar pyogenic spondylodiscitis treated with minimally invasive anterior debridement and fusion combined with posterior fixation via Wiltse approach / 华中科技大学学报（医学）（英德文版）

The effect and safety of anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach were assessed in the single-level lumbar pyogenic spondylodiscitis. Seventeen patients from 2007 to 2009 underwent anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach. Postoperative follow-up time was 24-41 months. Data included the patients' general information, microbiology, operative time, intraoperative blood loss, postoperative complications, intervertebral fusion rate, and preoperative and final follow-up scores for American Spinal Injury Association (ASIA) impairment, visual analogue scale (VAS), and Oswestry Disability Index (ODI). Ten patients had undergone a prior spinal invasive procedure, and 7 had hematogenous infection. The infected segments included L1-2, L2-3, L3-4, and L4-5 in 1, 2, 5, and 9 cases, respectively. Thirteen bacterial cultures were positive for Staphylococcus aureus (5 cases), Staphylococcus epidermidis (4), Streptococcus (3), and Escherichia coli (1). The operative time was 213.8±45.6 min, and the intraoperative blood loss was 180.6±88.1 mL. Postoperative complications consisted of urinary retention (2 cases), constipation (3), and deep vein thrombosis (2). On the final follow-up, VAS scores and ODIs were significantly lower than those of preoperation, while the ASIA grades improved. All the cases achieved good intervertebral bony fusion. Anterior debridement and fusion with a minimally invasive approach combined with posterior fixation via the Wiltse approach can successfully treat single-level lumbar pyogenic spondylodiscitis, with less trauma and reliable immobilization. It is a viable option for clinical application.

Experimental research on differentiation of immortalized human precartilaginous stem cells to nucleus pulposus-liked cells induced by TGF-β1 / 中华骨科杂志

Objective To explore the possibility of immortalized human precartilaginous stem cells (IPSCs) differentiating into nucleus pulposus-liked cells induced by transforming growth factor-β1 (TGF-β1)and examine its biological characters.Methods The IPSCs were seeded on the thermosensitive chitosan/glycerophosphate (C/GP) scaffolds and induced into nucleus pulposus-like cells in culture medium with the adding of TGF-β1 under hypoxia condiction.The growth and differrentiation of IPSCs on C/GP scaffolds were observed.Seven days later,Alcian blue staining was used to detect the formation of glycosaminoglycans (GAG) of extracellular matrix by the differentiating cell.RT-PCR was carried out to identify the expression of characteristic genes of nucleus pulposus-liked cells,including collagen Ⅱ and Aggrecan.Western blot were used to examine the expression of β-catenin.Results IPSCs grew well on the thermosensitive C/GP scaffolds.After 7 days,Alcian blue staining exhibited more formation of GAG in experimental group as compared with control group.RT-PCR manifested that the gene expression of collagen Ⅱ and Aggrecan were upregulated.Likewise,Western blot manifested that the expression of β-catenin was upregulated.Respectively,all of the content in the induction group obviously increased compared with that of the control group.Conclusion IPSCs can be differentiated into nucleus pulposus-like cells under the induction of TGF-β1,the differentiating cells have a favourable secretory function,which can secrete extracellular matrix effectively.Differentiation of IPSCs to nucleus pulposus-liked cells may be through upregulating the expression of β-catenin in cells.

Experimental research on spinal fusion with recombinant human bone morphogenetic protein-2 and bone marrow stromal cell composited tricalcium phosphate (TCP) / 生物医学工程学杂志

This paper is aimed to assess the efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) and bone marrow stromal cell (BMSCs) composited tricalcium phosphate (TCP) in a rat model of posterolateral lumbar intertransverse process fusion. Rat BMSCs were cultured in vitro. Twenty SD rats underwent single-level bilateral intertransverse process spine arthrodesis at L4 and L5. These rats were assigned to two groups according to the graft materials. They received: 10 of the total were treated with the BMSCs with rhBMP-2 and tricalcium phosphate (TCP) as the experimental group, and the other 10 with TCP treatment alone as the control group. All the animals were killed at 4 weeks after surgery and the spine fusion results were assessed by gross inspection, manual palpation, radiography and histology. The fusion rate, the tensile strength and stiffness of the solidly fused levels in the experimental group were statistically higher than that of the controlled group (P < 0.05). These results showed that the spinal fusion could be improved mechanically when rhBMP-2 and BMSCs were added into the TCP.

One-stage total en bloc spondylectomy by anterior and posterior approaches for lumbar vertebral tumors / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the surgical results of one stage total en bloc spondylectomy (TES) by anterior and posterior approaches for lumbar vertebral tumors and evaluate its benefit for these tumors.</p><p><b>METHODS</b>A total of 21 patients with the lumbar vertebral tumor treated with on stage TES by posterior and anterior approaches from April 2003 to August 2007 were reviewed, which included 14 males and 7 females with an average age of 47.6 years. Thirteen patients were suffered with the primary lumbar vertebral tumors and 8 patients were diagnosed for the lumbar vertebral metastasis tumors. There were 8 of S3, 3 of I A and 2 of II according to Ennekinng stage system. And there were 1 of Grade B, 4 of Grade C, 8 of Grade D, and 6 of Grade E according to Frankel grade system. The spinal reconstruction was obtained by titanium mesh filled with autograft for benign and low-grade malignant tumors and methylmethacrylate-filled titanium mesh for malignant tumors. The spinal stability was enhanced by posterior internal fixation with rod-screw system.</p><p><b>RESULTS</b>The operation time was 250 min and bleed loss was 2100 ml on average. The follow-up period lasted from 1.0 to 5.5 years. All cases had pain before operation, among which 14 cases obtained complete relief and 7 cases obtained partly relief after operation. In all cases with neurological deficit, they improved neurologically by more than one grade using the Frankel grading system. Up to now, 1 patient had be local recurrence after operation and 4 patients were dead on the following time. The others still are alive and no local recurrence.</p><p><b>CONCLUSION</b>One-stage TES by anterior and posterior approaches for lumbar vertebral tumor is feasible, safe and effective to lumbar vertebral tumor resection and stability reconstruction, which has many advantages such as controlling local recurrence, spinal cord decompression thoroughly, relieving the pain, improving the life quality and prolonging the lifetime.</p>

Treatment of adolescent idiopathic scoliosis with posterior simultaneous correction by bilateral corrective rod on the convex and concave sides / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy and clinical value of the strategy of posterior simultaneous correction by bilateral corrective rod on the convex and concave sides in the treatment of adolescent idiopathic scoliosis (AIS).</p><p><b>METHODS</b>From February 2006 to August 2008, posterior fusion was performed to 48 AIS patients. There were 16 males and 32 females, with an average age at the time of surgery of 17.1 years. Lenke Type I was found in 17 cases, Type II in 9, Type III in 14 and Type IV in 8. There were 27 patients used selective posterior fusion in thoracic, 21 cases without selective fusion. Observation index: the Cobb angle on coronal plane, translation and rotation of apical vertebrae, the coronal balance, the Cobb angle on sagittal plane, obliquity between lowest instrumented vertebrae (LIV) and the pelvis, intervertebral angle and rotation of the LIV. The patients were followed up at an average time of 15.1 months (12-27 months).</p><p><b>RESULTS</b>In the 27 cases with selective fusion, thoracic coronal Cobb angle was (17 + or - 8) degrees after the operation, with an average correction rate of (76 + or - 11)% at final follow up. The lumbar Cobb angle was (13 + or - 7) degrees after the operation, with an average correction rate of (72 + or - 9)% at final follow up. In the 21 cases without selective fusion, the thoracic Cobb angle was (20 + or - 7) degrees after the operation, with an average correction rate of (74 + or - 15)% at final follow up. The lumbar Cobb angle was (16 + or - 8) degrees after the operation, with an average correction rate of (69 + or - 9)% at final follow up. The average number of vertebrae retained below LIV was 4.4. There was 1 case developing thoracolumbar kyphosis. During the follow up, there were no major complication of neurological injury, no pseudarthrosis and no spine decompensation.</p><p><b>CONCLUSION</b>Posterior bilateral segmental pedicle screw simultaneous correction technique as a technique for correcting thoracic and lumbar curves scoliosis can improve the treatment of idiopathic scoliosis with fewer vertebral fusion and complications.</p>

Immortalization of human precartilaginous stem cells by transfecting SV40Tag / 华中科技大学学报（医学）（英德文版）

Immortalized human precartilaginous stem cells (IPSCs) were established to provide stable cell resource for the study of the molecular mechanism of gene targeting on the differentiation of PSCs. Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs by using lipofectin transfection. Colonies were isolated by puromycin selection and expanded by multiple passages. Immunohistochemistry, RT-PCR and Southern blotting were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines. The positive colonies were isolated and subcultured, designated immortalized precartilaginous stem cells (IPSCs), which were confirmed as fibroblast growth factor receptor-3 (FGFR-3) positive cells by immunohistochemistry and RT-PCR. SV40Tag cDNA was found in cultured IPSCs of passage 8 by Southern blotting, and the expressions of SV40Tag mRNA and protein were confirmed by RT-PCR. These findings suggested that IPSCs strain with SV40Tag was constructed successfully.

Immortalization of human precartilaginous stern cells by transfecting SV40Tag / 中华创伤骨科杂志

Objective To establish the strain of immortalized human precartilaginous stem cells (PSCs) which can be a stable cell resource for study of the molecular mechanism of gene targeting on differ-entiation of PSCs. Methods Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs using lipofeetin transfection method. Colonies were isolated by puromycin selection and expanded by many passages. Immunohistochemistry, RT-PCR and Southern blot were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines. Results The positive colonies were isolated and subcultured, named as immortalized precartilaginous stem cells (IPSCs), which were confirmed as positive to fibrnblast growth factor receptor-3 (FGFR-3). The existence of SV40Tag cDNA was detected by Southern blot and the expression of SV40Tag mRNA and protein by RT-PCR and immunohistochemistry. Conclusion IPSCs strain with SV40Tag can be constructed successfully.

The effect of pulsed electromagnetic fields on the proliferation of immunomagnetically separated human pre-cartilaginous stem cells / 中华物理医学与康复杂志

Objective To study the biological effects of pulsed electromagnetic fields (PEMFs) on the pro-liferation of immunomagnetically separated human precartilaginous stem cells (PSCs) in vitro. Methods The cells from an aborted fetus's metaphysis were digested using collagenase. The PSCs were isolated by magnetic cell sorting (MACS), then subcultured and amplified. Flow cytometry, immunohistochemistry, immunofluorescence and RT-PCR analysis were performed to identify the purified PSCs. The PSCs were stimulated by PEMFs at 50 Hz frequency and 1 mT intensity. Cell proliferation was measured at different time points using methyl thiazolyl tetrazolium ( MTT), and the cell growth curve was plotted. Flow cytometry was applied to measure the cell cycle and apoptosis. Results The PSCs were successfully cultured. There was fibroblast growth factor receptor-3 (FGFR-3) on their sur-face. Cell proliferation was promoted after 4 and 6 days of PEMF stimulation. The percentage of cells at the S phase was higher than in a control group. Early, late and total rates of apoptosis in the experimental group decreased signifi-cantly. Conclusion PEMFs can enhance the proliferation and inhibit the apoptosis of human PSCs, and it is possi-ble to cultivate the high density human PSCs in vitro.

Differentiation of rat adipose tissue-derived mesenchymal stem cells towards a nucleus pulposus-like phenotype in vitro / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To differentiate rat adipose tissue-derived mesenchymal stem cells (ADSCs) into cells with a nucleus pulposus-like phenotype in vitro, so as to lay a foundation for the cell-based transplantation therapy of degenerated intervertebral discs.</p><p><b>METHODS</b>Rat ADSCs were isolated only from the subcutaneous inguinal region and purified by limited dilution. ADSCs of the third passages were analyzed by fluorescence activated cell sorter (FACS) to detect the cell surface markers (Sca-1, CD44, CD45, CD11b). To induce ADSCs towards a nucleus pulposus-like phenotype, ADSCs were immobilized in 3-dimensional alginate hydrogels and cultured in an inducing medium containing transforming growth factor-beta1 (TGF-beta1) under hypoxia (2% O(2)), while control groups under normoxia (21% O(2)) in alginate beads in medium with or without the presence of TGF-beta1. Semiquantitative reverse transcription polymerase chain reaction (RT-PCR) was carried out to evaluate phenotypic and biosynthetic activities in the process of differentiation. Meanwhile, Alcian blue staining were used to detect the formation of sulfated glycosaminoglycans (GAGs) in the differentiated cells.</p><p><b>RESULTS</b>The purified ADSCs were fibroblast-like and proliferated rapidly in vitro. The flow cytometry showed that ADSCs were positive for Sca-1 and CD44, negative for CD45 and CD11b. The results of RT-PCR manifested that the gene expressions of Sox-9, aggrecan and collagen II, which were chondrocyte specific, were upregulated in medium containing TGF-beta1 under hypoxia (2% O(2)). Likewise, gene expression of HIF-1a, which was characteristics of intervertebral discs, was also upregulated. Simultaneously, Alcian blue staining exhibited the formation of many GAGs.</p><p><b>CONCLUSIONS</b>The approach in our experiment is a simple and effective way to acquire a large quantity of homogenous ADSCs. Rat ADSCs can be differentiated into nucleus pulposus-like cells. ADSCs may replace bone marrow mesenchymal stem cells as a new kind of seed cells in regeneration of degenerated intervertebral discs using cell transplantation therapy.</p>

Effect of rhBMP-2 and Osteogenic Revulsants on Proliferation and Differentiation of Bone Marrow Stromal Cells in Rats / 华中科技大学学报（医学）（英德文版）

The effects of recombinant human bone morphogenetic protein-2 (rhBMP-2) and osteo- genic revulsants alone or in combination at different time points and in different dosages on prolifera- tion and osteogenesis of bone marrow stromal cells (BMSCs) in SD rats were investigated. Rat BMSCs were cultured in vitro and induced by rhBMP-2 in different dosages (10, 50, 100 and 2013μg/L) alone or in combination with osteogenic revulsants. MTT colorimetric assay was used to evaluate The proliferation, activity of alkaline phosphoric (ALP) and osteocalcin were measured at 3rd, 6th, 9th, 12th day respectively. The results showed that rhBMP-2 and osteogenic revulsants could promote the differentiation of BMSCs towards osteoblast phenotype. The proliferation of BMSCs could be enhanced by rhBMP-2 in a dose-dependent manner. The expression of osteoblast phenotype was significantly higher by using both of them than by using them alone, which was veri- fied by the activity of ALP and osteocalcin. It was suggested that the combined use of rhBMP-2 and osteogenic revulsants could promote the proliferation and simultaneously induce and maintain the expression of osteoblast phenotype of BMSCs in rats.

Experimental investigation on therapy of intravenous transplantation of neural stem cell for spinal cord injury / 中国矫形外科杂志

[Objective] To investigate the immigration and differentiation of neural stem cell in vivo after intravenous transplantation into adult rats with spinal cord injury.[Method]Lower ventricle tissue was obtained from new-born rats aged 14 to 16 days,and the target cells were identified after cultured in vitro,neural stem cells signed by Brdu was injected into model rats of full-cut spinal cord via tail vein one week after injury.CSEP test and BBB function evaluation were conducted 8 weeks later after transplantation.The specimens made from the injured spinal cord of rats were affused with 8% poly formaldehyde,which aimed to get pathology section and imunnohistochemical staining.[Result](1)According to BBB scores,functional recovery was found in injury group and transplantation group but did not reach normal level,while in transplantation group the functional recovers got the better.(2)cerebro-spinal evoked potential(CSEP)in control group and injury group disappeared,and the latency period of CSEP in transplantation group was prolonged,but control group was not interfered.(3)Compared with injury group,a large amount of Brdu positive cells existed at the injured part of spinal cord in the transplant group,which indicated that the engrafted NSCs could survive and migrate into the injured part,and some of them could differentiated into the glial fibriuary acidic protein(GFAP)and NF-200 positive cells that had characteristics of neuron or glial cell.[Conclusion]Neural stem cell can reach the injured part of spinal cord and replace the injured neuron or glial cell via intravenous transplantation,which enable the injured spinal cord to functionally recover to some extent.

Effects of Co-grafts Mesenchymal Stem Cells and Nerve Growth Factor Suspension in the Repair of Spinal Cord Injury / 华中科技大学学报（医学）（英德文版）

To investigate effect of the transplantation of mesenchymal stem cells (MSCs) in combination with nerve growth factor (NGF) on the repair of spinal cord injury (SCI) in adult rats, spinal cord of adult rats (n= 32) was injured by using the modified Allen' s method. One week after the injury, the injured cords were injected with Dubecco-modified Eagles medium (DMEM , Group Ⅰ), MSCs (Group Ⅱ), NGF (Group Ⅲ), and MSCs plus NGF (Group Ⅳ). One month and two months after the injury, rats were sacrificed and their injured cord tissues were sectioned for the identification of the transplanted cells. The axonal regeneration and the differentiation of MSCs were examined by immunocytochemical staining. At the same time, rats were subjected to behavioral tests by using the open-field BBB scoring system. Immunocytochemical staining showed that axonal regeneration and the transplanted cells partially expressed neuron-specific nuclear protein (NeuN) and glial fibrillary acidic protein (GFAP). At the same time, significant improvement in BBB locomotor rating scale (P＜0.05) were observed in the treatment group. More importantly, further functional improvement were noted in the combined treatment group. MSCs could differentiate into neurons and astrocytes. MSCs and NGF can promote axonal regeneration and improve functional recovery. There might exist a synergistic effect between MSCs and NGF.

Expression of adenovirus-mediated glial cell line-derived neurotrophic factor gene in bone marrow stromal cells in vitro and its biological activity / 中国组织工程研究

BACKGROUND: Bone marrow stromal cells(BMSCs) are the ideal gene target cells and will have a bright future in the gene therapy of spinal cord injury.OBJECTIVE :To detect the expression of glial cell line - derived neurotrophic factor(GDNF) gene after BMSCs were infected by adenovirus-medialed GDNF (Adv-GDNF) in vitro and to explore its biological activity.DESIGN: A randomized controlled trial study.SETTING: Laboratory of Orthopedic DepartmentMATERIALS: The experiment was completed in the Laboratory of Orthopedic Department, Affiliated Tongji Hospital of Tong ji Meidcal College,Huazhong University of Science and Technology. Twenty-four SD rats of either gender, weighing (180 ± 20) g.INTERVENTIONS: BMSCs were infected by Adv-GDNF in vitro and then cocultured with spinal cord dorsal root ganglion. The three methods, immunofluorescent chemistry, reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay(ELISA) were used to evaluate GDNF expression in the BMSCs. The biological activity of GDNF was observed by a phase contrast microscope.MAIN OUTCOME MEASURES:Primary outcomes:①RT-PCR;②results of immunofluorescent chemical examination;③biological activity of GDNF in vitro. Secondary outcomes:①culturing and identification of BMSCs②time-effect relationship of GDNF expression revealed by ELISA.RESULTS: Immunofluorescence displayed expression of GDNF in BMSCs 48hours after Adv-GNDF infection. RT-PCR analysis demonstrated expression of GDNF mRNA 24 hours after Adv-GNDF infection. ELISA confirmed the presence of GDNF in the liquid supernatant of BMSCs 24 hours after Adv-GDNF infectionn and showed that GDNF was secreted. The supernatant can promote the neurite outgrowth in the rat dorsal root ganglion(DRG).CONCLUSION: It is demonstrated that BMSCs infected by Adv-GDNF can express GDNF steadily and the expressed GDNF has the activity of promoting neurite outgrowth, which lays a foundation of the GDNF gene therapy for spinal cord injury.

Effects of naloxone at different doses on neurons of cerebral cortex in rats / 中国组织工程研究

BACKGROUND: Naloxone has a significant arousal effect on many types of comas. It is usually believed that this is because its inhibition on endogenous opioid peptides. But depth of coma is not necessarily positively correlated to endorphin (EP).OBJECTIVE: Based on existing findings on direct stimulating effect of naloxone on cerebral cortex, further studies need to be done to explore whether it is dose-dependent or not.DESIGN: Single-factor design based on cells.SETTING: Neurology department in a university hospital and the neurology department in a hospital of a military medical university of Chinese PLA.MATERIALS: This study was completed in the Laboratory Center of Tongji Medical College, Huazhong University of Science and Technology. Thirty healthy new born Wistar rats, regardless of their gender, aging 8 - 12 days and weighing 150 -250 g, were selected.METHODS: The experiment was performed at room temperature. The perfusion slot were placed on the microscope stage, and cells with smooth surfaces, triangle or pyramidal shapes, strong refraction and more than one neurites were selected for patch clamp experiment. Patch clamp whole-cell recording technique was used to measure the pyramidal cells of the frontal lobe immediately after separated from the Wistar rats, and to investigate the fluctuations of their membrane potential of cerebral cortex neurons and the frequencies of their spontaneous electric activities after administration of naloxone at different doses.MAIN OUTCOME MEASURES: The neural excitatory reaction rate, depolarization amplitude and increasing rate of spontaneous electric activities after administration of different doses of naloxone were selected as main outcome measurements.RESULTS: The excitatory reaction rates of cerebral cortex neurons immediately after separation to doses of naloxone(100, 50, 10, 1, 0. 1 μmol/L)were 83%, 67%, 86%, 71% and 33%; while the depolarization amplitude of them were 9. 8, 9.6, 8.4, 5.2 and 1. 3 mV respectively; and the corresponding spontaneous electric activity were increased by 587% , 375% ,291%, 125% and 69%.CONCLUSION: Naloxone can induce excitatory reactions in cerebral cortex neurons directly, and the reactions have proved to be dose-dependent.

Progress in research on fixation with calcium phosphate cement strengthening screw / 中华创伤骨科杂志

When the patients with senile or secondary osteoporosis are treated with screw fixation, the screws are likely to get loose or pulled out. Polymethylmethacrylate (PMMA) can enhance screw fixation strength to some extent in clinic, but PMMA has such disadvantages as irresorbability, polymeric heating effect and toxic reaction so that its clinical application is limited. Calcium phosphate cement, however, has drawn much attention because it gets rid of the shortcomings of PMMA. This article introduces recent progress made in research on fixation with calcium phosphate cement enhancing screw.