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.

Objective To evaluate the role of autophagy on acute kidney injury after liver transplantation.Method Fifty-six healthy male Sprague-Dawley rats were randomly assigned into 4 groups:sham group,orthotopic liver transplantation (OLT) group,sirolimus pretreated (SRL) group and 3-methyladenine pretreated(3-MA) group.OLT model was established.Then the rats were sacrificed at 6 h after reperfusion.The renal function and the extent of oxidative stress relative proteins malondialdehyde (MDA) and superoxide dismutase (SOD) were observed.The levels of apoptosis relative genes caspase-3 and cyt c and the expression of autophagy relative proteins were detected.The pathological changes were microscopically examined in renal tissues.TUNEL staining was used to observe the apoptosis of tubular epithelial cells.Transmission electron microscopy was applied to observe the ultrastructure changes of tubular epithelial cells.Result As compared with sham group,OLT and 3-MA groups showed a serious renal injury including cellular vacuolization,loss of brush borders,and a significant rise in BUN,Cr and MDA,while a decrease in SOD activity.The levels of caspase-3 mRNA and cyt c rnRNA were increased significantly.Whereas compared to OLT and 3-MA groups,renal function and oxidative stress levels in SRL group ameliorated,and histopathologic damage and apoptosis alleviated after OLT.Simultaneously,the levels of caspase-3 mRNA and cyt c mRNA were decreased.The expression of beclin-1 and LC3-]Ⅱ was effectively upregulated.Conclusion Autophagy could alleviate acute kidney injury after liver transplantation through inhibiting oxidative stress and apoptosis.

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.

Objective To study the effects of extracellular-signal regulated kinase mitogenactivated protein kinase (ERK-MAPK) signaling pathway inhibition on histone phosphorylation and the related gene expression in human colorectal cancer cells.Methods Two human colorectal cancer cell lines (SW1116 and HCT116) were cultured and treated with gradient(0,20,40/μmol/L) doses of ERK-MAPK signaling pathway inhibitor U0126.Cell viability was determined by cell counting kit 8 (CCK-8) assay.Cell cycle distribution was assessed by flow cytometry.The expression levels of histone H3 kinases including ribosomal S6 serine-threonine kinase (RSK-2) and mitogen-and stressactivated protein kinase 1 and 2 (MSK1 and MSK2),and the levels of histone H3 (Ser10) phosphorylation and c-Fos protein were detected using Western blotting.Results Treatment of these two human colorectal cancer cell lines with ERK-MAPK inhibitor resulted in a time and dose-dependent inhibition of cell proliferation significantly. Proliferation rate of HCT116 was reduced to 47% at 72 hours after 40/μmol/L U0126 treatment. Cell cycle analysis showed that the percentage of phase G0/G1 cells significantly increased (P<0. 01) and the percentage of phase S cells decreased (P<0.01) after treatment with ERK-MAPK inhibitor. The expression of MSK1 and RSK2 reduced obviously in both of human colorectal cancer cell lines treated with U0126, which resulted in a 28% and 40% reduction of levels of MSK1 and RSK2 as compared with control HCT116 cells respectively,while no detectable change in the expression of MSK2 was found. Consistent with this, the expression level of histone H3 (ser10) phosphorylation was markedly down-regulated by ERK-MAPK inhibitor, and the related protein c-Fos expression decreased accordantly. Conclusions Decreased ERK-MAPK signaling pathway may reduce histone H3 (Ser10) phosphorylation via suppression of the activity of histone H3 kinase including MSK1 and RSK2, but not MSK2, consequently decrease the expression of c-Fos protein, which results in the inhibition of colorectal cancer cells proliferation.

Objective To observe the effect of aloe on intestine motility in the old costive mice and investigate the mechanism for aloe promoting an intestinal motility. Methods The content of aloin in aloe powder was determined by high performance liquid chromatography(HPLC).The old mice aged 15 months were randomly divided into 6 groups(10 in each group):blank control,positive control,constipation model,low-dose aloe,middle-dose aloe,high-dose aloe plus model.The mice of with equivalent volume of distilled water.On the eighth day,the mice except control group were given Compound Diphenoxylate to establish constipation model. With the black Indian ink as marker,the first time of black stool discharge,the character and weight of the stool,and the ink propulsion rate by intestines in mice were observed respectively.The serum level of nitric oxide(NO)was determined by spectrophotometry. Results The content of aloin in aloe powder was 0.266%.Compared with constipation model group,aloe groups in different dose decreased the first black stool time and increased stool grains and weight in 6 hours of constipated mice.The ink propulsion rates of intestines in the aloe groups were significantly higher than that of model group as well.The NO level in high-dose aloe group decreased more significantly compared with model group(P＜0.05),and there was a negative correlation between the serum NO level and propulsion rate of intestines(r=-0.346.P＜O.05). Conclusions Aloe could promote the mobility of intestine and ameliorate the constipation of mice,which might attribute to the decrease of the serum NO level.

Objective To evaluate the diagnosis and surgical treatment of primary hyperparathyroidism (PHPT). Methods 53 patients with PHPT who were treated in our hospital from 1997 to 2009 were analyzed retrospectively. Results All patients showed hypercalcemia and elevated parathyroid hormone (PTH). Among them, 43 were diagnosed as parathyroid adenoma, 6 were parathyroid hyperplasia and 4 were parathyroid cancer.The accuracy rate of parathyroid tumor localization was above 94. 3%. All patients presented temporary hypocalcemia after surgery. Conclusions Parathyroidectomy is an effective approach for patients with PHPT. Preoperative localization is essential to the surgery.

Objective To analyze the effect of eukaryotic expression vector containing sense and antisense DNA methyltransferase (DNMT1) gene on the transcript level of tumor associated genes in human colon cancer cell line. Methods Recombinant plasmid, including sense DNMT1 (HMT) and antisense DNMT1 (THM) gene, were constructed and transfected into SW1116 cell by using the lipofectamine. Then G418 filtration was performed. The expression of DNMT1 protein was examined by Western blotting. The transcription level of hMLH1, hMSH2, c myc and p16 INK4A genes were detected by RT PCR. Results The sense and antisense eukaryotic expression vectors were successfully constructed and then the constructed recombinant plasmids were transfected into SW1116 cell. The protein levels of DNMT1 have been up regulated and down regulated in SW1116 cells transfected with HMT and THM plasmids, respectively. The mRNA level of hMLH1, hMSH2, c myc gene were down regulated in the sense DNMT1 transfected cell. The mRNA level of hMSH2 was up regulated in the antisense DNMT1 transfected cell. However, the transcription level of p16 INK4A gene could not be associated with DNMT1 in SW1116 cell.Conclusion DNMT1 can regulate the expression of the tumor associated genes in human colon cancer cell line SW1116.

Objective To investigate the effects of Helicobacter priori (H.prlori) strains from the patient with gastric cancer on the expression of DNA mismatch repair (MMR) genes in AGS cells in vitro. Methods AGS cells were co-cultured with ten strains of H.prlori from five patients with gastric cancer and five patients with gastritis respectively.The expressions of DNA MMR genes (hMSH2 and hMLH1) in mRNA and protein levels were determined by RT-PCR and Western blot.The enteropathogenic E.coli served as a bacterial control.Results E.coli and H.priori strains from gastritis have no effects on the expression of hMSH2 and hMLH1 in both protein and mRNA levels on the whole,while all the H.prlori strains from gastric cancer reduced expression levels of hMSH2 and hMLH1.Conclusions There are different effects between H. prlori strains from gastric cancer and those from gastritis on DNA MMR in AGS cell line,indicating that infec- tion of some H.prlori strains might lead to the inhibition of DNA MMR,and that in turns increases the risk of gastric carcinogenesis during chronic H.prlori infection.

Objective To explore a new method of functional reconstruction of hand digits and joints with free transfer of foot tissues so as to increase the success rate of the operation.Methods After micro-anatomic study of the plantar and dorsal metatarsal arteries,retrograde and free grafts of foot tissues pedicled with plantar metatarsal arteries were designed and applied in transplantation to treat 76 cases of hand digital or joint defects.The surgeries included 58 cases of transfer of the second toe,four cases of transfer of composite tissues of the second toe, eight cases of transfer of proximal interphalangeal joint,and six cases of nail flap transfer.Results The mi- cro-anatomic study found that the first plantar metatarsal artery was anatomically constant and the diameter of its branch to the second toe was larger than that of the first dorsal metatarsal artery.Flaps survived in 75 of the 76 patients(98.7%),with fine appearance and significantly improved function.One patient who had received free transfer of the second toe to reconstruct the thumb function had to undergo a second repair with infraclavicula skin tube because of refractory arteriospasm of anastomosed vessels.Conclusion Transfer with free retrograde grafts of foot tissues pedicled with plantar metatarsal artery to reconstruct hand functions can effectively improve the success rate of the operation,because it is free of the shortcomings of great anatomic variation of blood vessels and time-consuming and complex procedures in conventional transfer.

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.