With deeper understanding for intervertebral disc degeneration,the development and clinical application of protocols in molecular biology,biological intervention in initial stage of intervertebral disc degeneration can retard even reverse the degeneration process. Gene therapy of intervertebral disc degeneration refers to the selection of animal models and gene carriers,application of target genes,etc. It is the key for gene therapy to build human-like animal model,select proper gene carrier and apply ideal target genes. Prior to clinical application,the safety and efficacy of gene therapy should be proved,thus many problems deserve further study.

In the human body, the structure of the organ and tissue is its functional foundation. With the human body skin losing, the skin also loses its function. When the skin defect area is quite large, it is the question that the source of the autologous skin is deficient. But with the engineering research progressing, the application of artificial skin to repair the skin defect is possible. In order to make the tissue-engineered skin have "normal" skin function, the structure research also should make them approach as far as possible to be similar. This article reviews the constructs, properties and applications of the epidermal substitutes, the dermal substitutes and the skin substitutes. With continued development of multi-discipline and continued progress of basic and clinical research, the constituted tissue-engineered skin substitutes will more approach the normal skin in the structure and properties.

AIM: To explore the possible anti apoptotic mechanism of ginsenoside Rg1 on MPP + induced cellular apoptosis. METHODS: The apoptosis of SHSY5Y induced by MPP + was observed by AO EB staining. Flow cytometry was used to quantitate mitochondrial transmembrane potential (△?m) and reactive oxygen species (ROS) . Western Blot was used to detect the expression of bcl 2 and bax proteins in SHSY5Y cells. RESULTS: MPP + induced apoptosis in SHSY5Y cells was obviously inhibited by pretreatment with 10 ?mol?L -1 Rg1. Although there was no difference of mitochondrial transmembrane potential between Rg1 pretreated groups and MPP + groups, the level of ROS in Rg1 pretreated groups decreased, the expression of bcl 2 protein increased and expression of bax protein decreased. CONCLUSION: Rg1 protects against MPP + induced apoptosis in SHSY5Y cells and the effect may be attributed to its remove of ROS and its regulation of expression of bcl 2 and bax proteins.

Objective To investigate the effects of caspase\|3 on ? ?? 1 40 induced apoptosis in rat cortical neurons. Methods Apoptosis was induced by 40?mg\5L -1 ?\|AP 1 40 .The apoptotic neurons were observed by TUNEL staining and DNA gel electrophoresis.The activity and mRNA expression of caspase\|3 was measured by fluorescent spectrofluorometer and RT\|PCR.The cleaved caspase\|3 was detected with immunocytochemistry. Results After treatment with ?\|AP 1\|40 ,the rat cortical neurons showed DNA fragmentation.The expression of caspase\|3 mRNA ratio to ? actin was 0\^78,0\^85 and 0\^39 respectively after treatment for 12,24 and 48?h.Caspase\|3 activity was 133 24?7 47,192 16?11 03,88 87?4 24 MFI\5?g protein -1 \5h -1 .The cleaved caspase\|3 was observed within cytoplasm.Specific inhibitor of caspase\|3 Ac\|DEVD\|CHO inhibited caspase\|3 activation and blocked cortical neurons apoptosis markedly.Conclusion\ Caspase\|3 might be an executor during ? AP 1 40 induced apoptosis in rat cortical neurons.[

Objective To explore the possible molecular mechanism of Ginsenoside Rg1 preventing against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced substantia nigra neurons apoptosis in Parkinson disease(PD) mouse model. Methods C57BL mice were administrated(sc) with MPTP to produce PD mouse model.Different doses of Rg1(5.0,10.0,20.0*!mg/kg) were given(ip) prior 3*!d to MPTP in the pretreatment groups.Nissl staining,tyrosinehydroxythase(TH) immunostatining,cleaved caspase-3 immunostatining and TUNEL staining were used to observe the changes of nigra neurons,meanwhile,Western blot was used to detect the phosphorylated protein of JNK and c-Jun in substantia nigra. Results Pretreatment with Rg1 could prevent the loss of Nissl staining neurons and TH-positive neurons,inhibit JNK and c-Jun phosphorylation in SN,decrease the percent of cleaved caspase-3 and TUNEL-positive cell.Conclusion Rg1 can attenuate MPTP-induced apoptosis in substantia nigra neurons through blocking JNK signaling cascade.

AIM: To investigate the effects of nitric oxide(NO) and caspase-3 on dopamine-induced apoptosis in PC12 cells. METHODS: Flow cytometric assay was used to quantify the apoptotic cells. The morphological of apoptotic cells was evaluated by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL). Nitrite was quantified by Griess reaction. Inducible nitric oxide synthase(iNOS) mRNA was identified by semiquantitative reverse transcription polymerase chain reaction(RT-PCR). Caspase-3 activity was determined by fluorescent spectrofluorometer. RESULTS: Dopamine induced PC12 cells apoptosis in a concentration-dependent manner (0.15-0.60 mmol/L), with positive TUNEL staining. During the development of apoptosis, the expression of iNOS mRNA and the levels of NO increased markedly, so did caspase-3 activity(P

AIM: To explore the possible signal transduction pathway of 1-methyl-4-phenylpyridinium(MPP +)-induced apoptosis. METHODS: The apoptosis of SHSY5Y cells induced by MPP + was observed by acridine orange-ethidium bromide(AO-EB) staining. Western blot was used to detect the activity of JNK in SHSY5Y cells, and the antisense oligo- neucleutide of JNK were used as inhibitor of JNK. RESULTS: MPP + induced apoptosis in SHSY5Y cells. During the apoptotic process, JNK activity increased. MPP +-induced apoptosis in SHSY5Y cells was obviously inhibited by pretreatment with NAC or by transfection with antisense oligonucleotide of JNK into SHSY5Y cells. Simultaneously, decrease in JNK activity and percentage of positive cleaved caspase-3 cells in these groups were also observed. CONCLUSION: The possible signal transduction pathway of MPP +-induced apoptosis in SHSY5Y cells might be attributed to the production of ROS ,activation of JNK and then activation of caspase 3.

Objective To observe periventricular white matter changes and matrix metalloproteinase-3 (MMP-3) expression after two-vessel occlusion in rats.Methods A total of 40 Wistar rats were randomly divided into four groups:sham operation group,model group 1 (20 days after operation),model group 2 (40 days after operation),model group 3 (60 days after operation)(n =10 per group).Model of chronic cerebral hypoperfusion was induced by permanent ligation of the bilateral common carotid arteries in the rat.The change of periventricular white matter was observed by electron microscope.The myelin basic protein (MBP) levels was determined by Western blotting,and the expression of MMP-3 was analysed by immunohistochemical stain and Western blotting.Results Permanent ligation of the bilateral common carotid arteries resulted in demyelination in the corpus callosum and internal capsule in rats.The expressions of MMP-3 in model groups were markedly elevated compared with sham group (model group 1,39.17± 4.167; model group 2,43.33±3.502; model group 3,54.16±2.787; sham group,26.67±3.830; all P＜0.01).The content of MBP in model groups was gradually decreased compared with sham group (model group 1,54.50±4.087; model group 2,47.83±4.875; model group 3,36.50±4.231; sham group,65.01±7.688; all P＜0.01).Additionally,the upregulation of MMP-3 had significant correlation with the loss of MBP in the periventricular white matter (r =-0.883,P＜0.01).Conclusions Chronic cerebral hypoperfusion induces progressive periventricular white matter demyelination,and the upregulation of MMP-3 may involve in the pathological process.

Objective To evaluate the potential influencing factors associated with pathologic complete response ( pCR) after neoadjuvant chemoradiotherapy for locally advanced rectal cancer ( LARC) . Methods A retrospective analysis was performed on the clinical data 265 patients with stageⅡandⅢ( the 7th version of AJCC) rectal cancer admitted to our hospital from 2011 to 2013. All patients underwent neoadjuvant concurrent chemoradiotherapy ( CCRT ) followed by surgery with/or without induction chemotherapy during the interval between the complete of CCRT and surgery. The predictors associated with pCR were analyzed by univariate and multivariate logistic regression analyses. With the use of the independent predictive variables for pCR from multivariate analysis, a clinical risk score model was established according to the following criteria:no?risk group (0 factor);low?risk group (1 factor);high?risk group ( 2 factors) . Results Among these 265 patients, 50( 18. 9%) achieved pCR. The univariate analysis showed that carcinoembryonic antigen ( CEA) level before CCRT ( P=0. 017) , T stage before CCRT ( P=0. 001), interval between complete of CCRT and surgery (P=0. 000), and the maximum tumor thickness before CCRT ( P=0. 040) were significantly associated with pCR. The multivariate analysis showed that pre?CCRT CEA level ( P=0. 021 or 0. 446) and interval between the complete of CCRT and surgery ( P=0. 000 or 3. 774) were significant predictors of pCR. When stratifying for smoking status, only low pre?CCRT CEA level was significantly associated with pCR in the non?smoking patients ( P=0. 044) . For the prediction of pCR by the clinical risk score model, the sensitivity was 0. 805, the specificity was 0. 460, the area under the receiver operating curve was 0. 690 ( 95% CI= 0. 613?0. 767 ) , the positive predictive value was 35 . 4 9%, the negative predictive value was 8 6 . 5%, and the predictive accuracy was 7 3 . 9%. Conclusions For locally advanced rectal cancer, pCR can be achieved in some patients after neoadjuvant therapy. Low pre?CCRT CEA level and long interval time between CCRT and surgery are independent factors associated with pCR, and only low pre?CCRT CEA level is an associated factor in the group of nonsmokers. The clinical risk score model based on pre?CCRT CEA level>5 ng/ml and time interval from CCRT completion to surgery≤8 weeks can be used to predict pCR after neoadjuvant chemoradiotherapy for LARC.

AIM: To study the possible molecular mechanism of beta-amyloid peptide_ 1-40 -induced apoptosis in rat cortical neurons. METHODS: 40 mg/L beta-amyloid peptide_ 1-40 (A?_ 1-40 ) was used to induce apoptosis in cultured rat cortical neurons. The level of CDK4, phosphorylated pRB were detected by flow cytometry and immunoblotting; RT-PCR was used to examine the mRNA expression of E2F1 while fluorescent spectrofluorometer was used to measure caspase-3 activity. All of the above study was designed to observe whether the level of CDK4, phosphorylated pRB and E2F1 mRNA expression could be affected by A?_ 1-40 . RESULTS: (1)The level of CDK4, phosphorylated pRB increased markedly 2-4 hours after treatment with A?_ 1-40 , and caspase-3 activity elevated remarkably 12-24 hours after treatment with A?_ 1-40 ; (2) E2F1 mRNA expression was upregulated 3 hours after incubation with A?_ 1-40 . CONCLUSION: A?_ 1-40 may induce apoptosis in rat cortical neurons in a manner dependent on CDK4-pRB-E2F1 pathway.