As the components of proteoglycans, glycosaminoglycans (GAGs) are linear polysaccharides consisting of hexose and uronic acid units linked by β-1,3-glycosidic bond. GAGs mainly distribute in extracellular matrix and on cell surfaces. They guide many biological processes, such as proliferation of cells, transmission of signals and mediation of inflammation. Because of their large molecular weights, GAGs have limited biological functions in vitro. However, the appearance of chondroitinase ABC (ChSase ABC), which can lyse polysaccharides, solves the difficulties. Based on our work, we summarized the classification and the crystal structure of ChSase ABC, as well as other recent research progress on ChSase ABCs. The separation and purification methods of ChSase ABC and construction of engineering bacteria are illustrated. The stability and immobilization are also analyzed by taking account of the characterization of ChSase ABC. Finally, problems and future prospect of the ChSase ABC study are summarized.
Bacteria ; Chondroitin ABC Lyase ; chemistry ; Extracellular Matrix ; chemistry ; Glycosaminoglycans ; chemistry ; Proteoglycans ; chemistry

Objective:To compare the differences of cranial base morphology between high-angle and low-angle malocclusion patients with geometric morphometrics.Methods:Pretreatment lateral cephalograps of 80 skeletal Class I patients(40 hypodivergent,40 hyperdivergent)were selected.All cephalographs were scanned,and 13 homologous landmarks of cranial base were identified and digitized.Average geometries of cranial bas e were created by means of Procrustes analysis.Thin-plate spline analysis was applied to cranial base configurations to determine local morphology differences between the two vertical facial types.Results:1.high-angle patients had the cranial base characteristics as follow:(1)Horizontal and vertical expansion occured in the sphenoida region,(2)The anterial and posterior cranial bases circled S point opposite direction revolving,which caused cranial base angle to reduce significantly.2.The low-angle the cranial base characteristics was just opposite with high-angle′s.Conclusion:The shape of cranial base was different between high-angle and low-angle malocclusion patients.

Objective To explore the relationship among nurses′perceptions of patient safety culture, nursing practice environment and the report barrier of nursing adverse event. Methods Totally 513 registered nurses from six hospitals in Zhengzhou were investigated with Patient Safety Culture Assessing Scale, Work Environment Questionnaire and Report Barriers Questionnaire. Results The mean scores of nurses′perceptions of patient safety culture, nursing practice environment and report barriers of nursing adverse events were (3.85±0.55), (3.84±0.53) and (2.47±0.55). The nurses′perceptions of patient safety culture were positively correlated to nursing practice environment (r=0.393,P<0.01), negatively correlated to report barriers of nursing adverse events (r=-0.372,P<0.01). The influencing factors of nurses′perceptions of patient safety culture were colleague relationship, punitive culture, allocation of medical resources, marital status, quality control, significance of report, gender and education, which could explain 33.8 percent for the variances. Conclusions The level of nurses′perceptions of patient safety culture is higher than the average level. The nursing managers should build supportive nursing practice environment and the non-punitive reporting system of nursing adverse events. Cultivate the beliefs and attitudes of nursing safety and focus on the impact of occupational stress to patient safety in order to enhance safety nursing.

Objective To assess the clinical features and treatment of children with long QT syndrome (LQTS)and syncope.Methods Eleven cases of children with LQTS and syncope between January 2009 and July 2014 in Hunan Children′s Hospital were retrospectively analyzed for clinical features,treatment and long term follow -up.Results There were 11 cases of children with LQTS aged 4.0 -14.5(9.16 ±2.71)years,8 male and 3 female, with syncope more than once.The range of QTc was 460 -521(483.72 ±22.90)ms.For 3 cases of acquired LQTS,1 case was parathyroid hypothyroidism causing hypocalcemia,1 case was myocarditis complicated with third degree atrio-ventricular block,and 1 case showed atrial flutter receiving amiodarone post congenital cardiac surgery.All patients re-covered after the inducement removed and primary illness cured.For 8 cases of congenital LQTS,3 cases of LQTS un-derwent genetic test (1 case of KCNQ1 gene mutation,2 cases of KCNH2 gene mutation).One case died after frequent torsade de pointes (Tdp)and ventricular fibrillation during hospitalization,the remaining 7 patients were given oral pro-pranolol,potassium chloride sustained -release tablets after discharge.Follow -up time was 8 to 75 months,an average of (45.73 ±24.42)months.One case died suddenly at home after 25 months of follow -up.The remaining 6 cases of children with congenital LQTS could withstand general activities without syncope,in which 4 cases had normal QTc by electrocardiography(ECG),and the findings in 2 cases did not change compared with those previously.The QTc re-turned to normal in children with acquired LQTS in the follow -up review.Conclusions Children with congenital LQTS should receive early genetic screening and genotyping for rational use of drugs.For children with higher risk of sudden death,drug therapy combined with implantable cardioverter defibrillator should be considered.For acquired LQTS,it should be better to remove the inducement and treat primary disease actively.

OBJECTIVE: To study the effect of transplanting autologous bone marrow mesenchymal stem cells (BMSCs) at different time point after myocardial infarction on cardiac function, and to approach its mechanism. METHODS: Thirty healthy Taihu Meishan swine were prepared for myocardial infarction models, and divided into 6 experimental groups, with 5 animals in each group. BMSCs were transplanted into 3 groups through coronary artery at 3 hours, 2 weeks and 4 weeks after myocardial infarction, named G1, G2 and G4, respectively. Meantime, DMEM culture medium was injected in the control group at correspond periods. Each swine was examined by MRI and Doppler before infarction, before transplantation, and at 8 weeks after infarction, respectively, to observe the change of cardiac function. The VEGF values of blood serum in different periods after transplantation were detected. All swine hearts were harvested after 8 weeks (the experimental terminus), and the planting and differentiation of transplanted cells in cardiac muscle were detected by the method of immunity histochemistry. The density of blood vessels in cardiac muscle was acquired simultaneously. RESULTS: There was no statistic difference of cardiac function between G1 and its control groups. The groups of G2 and G4 could improve cardiac function compared to the control groups, and G4 was superior to G2 (P < 0.05). There was no statistics difference of the decreased absolute value of myocardial infarcted area between G1 and the control groups. The myocardial infarcted area of G4 was greater than G2 (P < 0.05). The value of blood serum VEGF rose obviously in the G2 and G4, while G1 and all control groups did not present any marked changes, the rising amplitude of G4 was larger than G2 (P < 0.05). There were not any planting and differentiation of transplanted stem cells in G1 and all control groups at 8 weeks after infarction, but G2 and G4 could display, especially in G4 group (P < 0.05). There was no statistic difference of the density of blood vessels in cardiac muscle between G1 and all control groups at 8 weeks after infarction, but the differences were significant in all experimental groups, which was superior in G4 group to G1 and G2 groups (P < 0.05).CONCLUSION: There is disparity of transplanting BMSCs at different time point after myocardial infarction on cardiac function. Transplantation in acute period of myocardial infarction has no significant effect, but transplantation in non-acute period can ameliorate cardiac function. The therapeutic effect of transplanted at 4 weeks is superior to other time point. The MRI can display the location and compass of infarct cardiac muscle, and reflect the variation of cardiac function.

Objective To investigate the genetic polymorphism of 90 autosomal SNPs in Guangdong Han population and assess their value in forensic medicine based on next generation sequencing. Methods Blood samples were collected from 100 unrelated individuals. Through using AutoMate ExpressTM Nucleic Acid Extraction System, DNA was extracted. HID-Ion AmpliSeq? Identity Panel was applied for library preparation while Ion OneTouch? 2 system (OT2) was employed for emulsion PCR (emPCR). NGS was performed on the Ion PGM? system. Sequencing results were analysed using the Torrent Suite v4.4.2 with the HID_SNP_Genotyper v4.3.1 plugin. The forensic parameters were calculated and compared with GoldeneyeTM 20A systems. Results According to the Bonferroni correction, the genotypes of 90 autosomal SNPs were in accordance with Hardy-Weinberg equilibrium and no linkage disequilibrium was observed. The average Ho of 90 autosomal SNPs was 0.423, the average DP was 0.560 and the average PIC was 0.329. The CDP (cumulative power of discrimination) of 90 autosomal SNPs system was 1-1.20×10-33, which was greater than that of 20A System. The CPEtri (cumulative excluding probability of trio paternity) was 0.999 999 911 and the CPEduo (cumulative excluding probability of duo paternity) was 0.999 882. Both of these two parameters were below that of 20A System. Conclusion It suggested that the 90 autosomal SNPs System can be applied to forensic individual discrimination and trio paternity testing independently. Besides, it is supposed to be used in the duo paternity testing as an assistant measure.

BACKGROUND: A great quantity of cell loss in early stage following stem cell transplantation can significantly affect transplantation effect. Presently, it is confirmed that overexpression of AKT1 gene significantly inhibit cell apoptosis. OBJECTIVE: To explore whether AKT1 gene overexpression can block stem cell apoptosis under hypoxic condition following pig autologous bone marrow mesenchymal stem cell (BMSC) transplantation, and the effect of repairing damaged myocardium. DESIGN, TIME AND SETTING: The randomized controlled animal study was performed at the Soochow University from August 2005 to February 2007.MATERIALS: A total of 24 healthy male Meishan pigs were supplied by the Animal Experimental Center of Soochow University. METHODS: The CDS (regulation domin of AKT1) AKT1-cDNA fragment was amplified. Lentivector Packaging Kit was used to transfect BMSCs after synthesized with pCDH1-AKT1 shuttling plasmid. Following BrdU labeling, models of myocardial infarction were constructed by occluding the distal left anterior descending coronary artery in pigs with gelatin sponge. 4 weeks later, pigs were randomly divided into four groups: the model control group, the DMEM group, the BMSCs group, and the AKT-transfected group. In model control group, there was no other injection after occluding the left anterior descending coronary artery. In the DMEM group, 5 mL DMEM was injected into the coronary artery. 5 mL BMSCs (1×10~7 cells) were infused into the coronary artery in the BMSCs group. 5 mL BMSCs transfected with the AKT1 gene were injected in the AKT-transfected group MAIN OUTCOME MEASURES: Western blot analysis and real time RT-PCR were used to test the plasmid. The cardiac function was evaluated by magnetic resonance image. Histological characteristics of the myocardium were observed using immunohistochemistry. Serum vascular endothelial growth factor and transforming growth factor β1 levels were determined by ELISA. RESULTS: AKT1-cDNA was cloned into pCDH1-MCS1-EF1-copGFP and the sequence was confirmed in comparison with the published one. AKT mRNA expression could be detected distinctly 24 and 48 hours after transfecting cells. The expression of AKT1 intensity in MSCs remained strong 2 weeks later with detected by real time RT-PCR and Western blot analysis. AKT1-mRNA transcriptional levels were 120 times of primary cells. Before the cell implantation, the left ventricular end-diastolic dimension increased and the stroke volume decreased in the myocardial infarction hearts. The cardiac function was significantly improved after cell implantation, and the implanted MSCs prevented the infarct region from thinning and expanding, improved contraction and increased perfusion in all groups relative to the control hearts. The left ventricular chamber size was smaller in the hearts with being transplanted cells than that in the control hearts. Moreover, the improvement was even markedly greater in AKT-transfected group (P < 0.05). Hematoxylin-eosin staining results showed that fibering was significant in the model control group and DMEM group. Island-like myocardium was observed in the infarct zone of the BMSCs group and AKT-transfected group, and plenty of small vessels-shape structure was detected in the AKT-transfected group. Immunohistochemistry demonstrated that Von Willebrand Factor (vWF) and Cx-43 expression was determined in the myocardium in the BMSCs group and AKT-transfected group, and the proportion of BrdU and Cx-43-positive cells to BrdU-positive cells was significantly greater in the AKT-transfected group compared with the BMSCs group 4 weeks following transplantation (P < 0.05). Following cell transplantation, vascular endothelial growth factor levels were gradually increased, peaked at 1 week, gradually decreased, and reached a normal level at 4 weeks. Transforming growth factor p1 levels were gradually reduced, and significantly less than the model control group, DMEM group 4 weeks later (P < 0.05), and significantly lower than that pretransplantation (P < 0.05).CONCLUSION: Using lentiviral vector to construct with AKT1 gene could stably make BMSCs overexpress AKT1. The BMSCs engraftment in host myocardium might improve the left ventricle function by attenuating the contractile dysfunction and pathologic thinning in this model of left ventricular wall infarction. AKT1 overexpression can significantly improve cardiac function following infarction.

IL-18, as a polyphonic cytokine, is important in immune response and physiologic function. We designed one pair of primers, amplified the porcine IL-18 gene fused with a C-terminal 6xHistidine tag, and then subcloned into the pFastBacDual of Baculovirus transfer vector and transformed into DH10Bac containing a shuttle vector of Bacmid. After co-transfecting the recombinant plasmid into insect cells, the 18 kDa expressed protein of porcine IL-18 was detected by SDS-PAGE; the specificity of expressed protein was confirmed by Western blotting. The purified porcine IL-18 protein induced obvious proliferation of porcine T lymphocytes in vitro, which indicated that the expression of IL-18 had high biological activity.
Animals ; Baculoviridae ; genetics ; metabolism ; Cells, Cultured ; Genetic Vectors ; genetics ; Insecta ; genetics ; metabolism ; Interleukin-18 ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Swine ; Transfection

General education in biological courses such as "Principal Biology" is an essential avenue for gaining an understanding of life science and developing an interest in the field. The reform of biological education teaching mode based on interdisciplinary approaches aims to foster cross-disciplinary talents, which is crucial for the rapid development of China's bioeconomy. Teaching method that simply superimposes different subjects is difficult to discover the value of interdisciplinary education. To address this, a novel teaching system and an innovative teaching mode were proposed for "Principal Biology" course by integrating science and engineering subjects, based on the cross-disciplinary feature in Beijing Institute of Technology. The system involves the design of cross-disciplinary course content and the integration of multiple disciplines and knowledge points based on students' majors, taking into account the characteristics of students' physical and mental development. To improve students' scientific literacy and interdisciplinary thinking ability, differentiated and major-driven teaching modes were applied by incorporating the "1+N" mixed and immersive cross-thinking training. The effectiveness of tailored cross-disciplinary teaching was evaluated using "in-teaching" and "post-teaching" data feedback models, which promote the optimization of teaching process and enhance the quality of education in cross-disciplinary biological science.
Humans ; Students ; Curriculum ; Biological Science Disciplines/education* ; Universities ; Biology/education*