The method of PBL (problem based learning) teaching in China is widely recognized. However, the characteristics of Vocational Medical Education limit its wider application. The paper discusses the mode which is suitable for our country by analyzing the major issues,improving methods of teaching and doing experiments.

Course construction is the groundwork for vocational college to improve education quality. The first thing for the excellent course construction is to raise awareness. The fundamental starting point and destination are benefitial to students. It must start from the teachers themselves, and have entire optimization in the teaching content,teaching methods ,teaching materials, the means of teaching and so on.

Objective Protein N-SRCR derived from salivary agglutinin (SAG) inhibits HIV-1 infection.An N-SRCR monoclonal antibody was prepared for the study of the interaction between N-SRCR and HIV-1 envelop glycoprotein (gp120).Methods The purified recombinant N-SRCR expressed by 293 cells was used to immunize four weeks old BALB/c mice.After the final boost,the mouse spleen cells were isolated and fused with mouse myeloma cell line SP2/0-Ag-14,and the resulting hybridomas were screened for the production of N-SRCR-specific antibodies by ELISA assay.The monoclonal antibody against N-SRCR was purified by HiTrap Protein G kit,the purity determined by SDS-PAGE and the antibody titers by ELISA.The antibody specificity.was charqacterized by western blotting.Results A strain of hybridoma cell clones stably secreting N-SRCR antibody,named 1D6,was obtained.The high purity of the IgG was demonstrated by SDS-PAGE,and the ELISA titers of 1D6 was more than 100?25.Conclusion A monoclonal antibody against N-SRCR was successfully prepared,which laid the ground for further studies on the biological function of N-SRCR and the interactions between SRCR domains and HIV-1 Env gp120.

BACKGROUND:Stem celltumorigenicity is a practical issue concerning stability in the clinical application of stem cells. Therefore, it is particularly important to clear whether stem cells have tumorigenic ability or not. Nude mice occupy an increasingly important position in oncology, immunology, and safety evaluation of drugs and biological products.
OBJECTIVE:To observe the tumorigenicity of neural stem cells and mesenchymal stem cells in Balb/c nude immunodeficient mice.
METHODS:Balb/c nude mice were randomly divided into control group, negative group, positive group, neural stem cellgroup and mesenchymal stem cellgroup. HepG-2 cells, RPE cells, passage 4 neural stem cells and mesenchymal stem cells were injected subcutaneously into nude mice from different groups, respectively. After 12 weeks of injection, anatomical observation was performed to detect the tumor formation in the transplantation site. Meanwhile, soft agar colony formation assay was applied to investigate neural stem celland mesenchymal stem cellclone in vitro.
RESULTS AND CONCLUSION:After 12 weeks of injection, the tumorigenicity study results showed that no tumor developed in the transplantation site in the control group, negative group, neural stem cellgroup and mesenchymal stem cellgroup. Histopathologic examinations also showed no abnormality in these groups. Soft agar colony formation assay showed in soft agar resistance medium, neural stem cells and mesenchymal stem cells did not exhibit clone ability. These findings indicate that neural stem cells and mesenchymal stem cells undergoing short-term passages have no tumorigenic growth.

BACKGROUND:Stem cells expansion technology in vitro is affected by the microenvironment of the culture system. So, to find an effective method is particularly important to promote celladherent and growth. OBJECTIVE:To compare the effects of different culture media on cellexpansion. METHODS:Human umbilical cord mesenchymal stem cells at a density of 5.0×104 cells/cm2 were inoculated into Corning? polystyrene culture dishes coated with or without poly-L-ornithine and Corning? cellBIND culture dishes. celladhesion and proliferation were observed, and expressions of celladhesion proteins and cellmarkers were detected. RESULTS AND CONCLUSION:celladhesion was promoted when cells were cultured in Corning? cellBIND? Surface medium coated with poly-L-ornithine for 24 hours, and the cultured cells grew at the logarithmic phase. The cellproliferation was also enhanced, and the cells expressed celladhesion protein but not the cellmarkers of CD73, CD90, CD105. Corning? cellBIND? Surface medium was superior to Corning? polystyrene culture medium in the improvement of celladhesion and proliferation. Additional y, both of these two media showed no influence on cellphenotype. These findings indicate that Corning? cellBIND? Surface medium can promote celladhesion and proliferation, but shows no effects on cyclin and cellphenotype. This medium coated with poly-L-ornithine can further accelerate celladhesion and proliferation, and stably express cellphenotype of human umbilical cord mesenchymal stem cells.

Objective To investigate the value of case-based learning(CBL) combined with lecture-based learning (LBL) in medical immunology teaching.Methods Totally 85 clinical medicine students of 2010 grade in medical school of Yangtze university were divided into two groups:control group(n=43) and experimental group(n=42).The students in control group were received LBL while those in experimental group were received CBL combined with LBL.Teaching effectiveness was evaluated by questionnaire survey and theoretical test.Results The questionnaire showed that the abilities of comprehension,expression,analysis,practice and cooperation were significantly better in experimental group than in the control group(P＜0.05),the results of test showed that the total scores and the scores of choice and clinical case analysis were markedly higher in experimental group than in the control group(P＜0.05).Conclusions The teaching model of CBL combined with LBL is helpful to develop students' comprehensive quality and creative ability and it is worth further promoting in medical immunology teaching.But there are some problems need further improvement.

Objective To develop a HPLC method for determining the contents of lobetyolin and gallic acid in Eighteen Flavors Dangshen Pill(EFDSP) produced by different factories.Methods The HPLC analysis was performed on a VP-DOS C18 column (4.6 mm×150 mm,5 μm).The mobile phase was acetonitrile and 0.4% glacial acetic acid(21∶79) in the determination of lobetyolin content.The detection wavelength was 267 nm and the flow velocity was 1 mL/min.the column temperature was25 ℃ and the sample size was10 μL.The mobile phase was methanol and 0.4% glacial acetic acid(1∶99) in the determination of gallic acid content.The detection wavelength was 280 nm.The column temperature was 25 ℃ and the sample size was 10μL.Results The contents of lobetyolin and gallic acid in EFDSP were 1.0835mg·g-1and 15.334 0 mg/g for Qinghai Gela Dandong Tibetan Pharmaceutical Factory;0.628 9 mg/g and 15.159 5 mg/g for Changdu Tibet Medicine Factory;0.306 5 mg/g and 8.762 7 mg/g for Tibetan Hospital of Tibet.Conclusion This method has the advantages of good reproducibility,good accuracy,simple and fast operation.The contents of lobetyolin and gallic acid in EFDSP produced by different manufacturers are significantly different.The gallic acid content has greater difference.It provides the reference for quality control of EFDSP

Objective To assess the efficacy and safety of berberine, amoxicillin, lansoprazole, bismuth quadruple therapy for Helicobacter pylori (H.pylori)eradication.Methods From December 2015 to April 2016,566 patients with initial treatment of H.pylori infection were prospectively enrolled.Patients were divided into observation group (berberine, amoxicillin, lansoprazole, bismuth) and control group (clarithromycin, amoxicillin, lansoprazole, bismuth), 283 cases in each group, and the treatment courses in two groups were both 14 days.Four weeks after completion of the treatment, the eradication rate of H.pylori and adverse effect rate of the two groups were compared.Student t test and Chi square test were performed for comparison between the two groups.Results There was no statistically significant difference in the baseline demographic data including gender,age, body mass index (BMI), symptom score between patients of the two groups (all P>0.05).Four weeks after completion of the treatment, the eradication rates of observation group and control group were 87.5%(244/279) and 87.1%(242/278) according to per-protocol analysis, and which were 86.2%(244/283) and 85.5 %(242/283) according to intention-to-treat analysis.There was no statistically significant difference between the two groups (x2=0.021,0.058;both P>0.05).The adverse effect rates of the two groups were 12.5%(35/279) and 16.5%(46/278), and there was no statistically significant difference (x2=1.795,P=0.180).Conclusions Both the new quadruple regimen containing berberine, amoxicillin and bismuth, and the standard quadruple regimen containing clarithromycin, amoxicillin and bismuth both can effectively eradicate H.pylori infection.The new regimen might be recommended as first-line eradication regimen in Xi′an district or area with high clarithromycin resistance.

Objective:To compare drug-coated balloon (DCB) and standard angioplasty balloon (SAB) in the treatment of postoperative in-stent restenosis (ISR) in patients with arteriosclerosis obliterans (ASO) of the lower extremity.Methods:From Jan 2017 to Dec 2018, 43 ISR patients after percutaneous transluminal angioplasty for ASO of the lower extremity at our hospital were enrolled.Patients were divided into 2 groups with 18 patients treated by DCB and 25 by SAB. The patients were followed up for 6~12 months.Results:There was no significant difference in the incidence of complications between DCB group and SAB group ( P>0.05).Compared with that in SAB group, the plasma level of ET-1 in DCB group was lower while NO was higher at 6, 24 h and 2 weeks after surgery ( P<0.05), there was no significant difference in P-selectin ( P>0.05). The ABI values in both groups increased, and that in DCB group were higher than SAB group at 6 and 12 months after surgery ( P<0.05). The lumen loss in DCB group at 6 and 12 months after surgery was significantly lower ( P<0.05). At 6 and 12 months, the primary patency of target lesions in the DCB group was 100.00% and 88.89%, which was higher than the 72.00% and 52.00% in the SAB group ( P<0.05); the CD-TLR rate in the DCB group was 11.11%, which was lower than 48.00% in the SAB group ( P<0.05). Conclusion:DCB comes with lower postoperative ISR in ASO patients of the lower extremity.

Objective: To investigate the expression of microRNA (miRNA, miR)-126 in esophageal carcinoma tissues and the effect of miR-126 on the proliferation and migration of esophageal cell line EC109. Methods: The expressions of miR-126 and sex determining region Y-box 2 (SOX2) mRNA in esophageal cancer tissues and their paracancerous tissues from 24 patients were detected by real-time fluorescence-based quantitative PCR. The expression of miR-126 in EC109 cells after transfection with miR-126 mimics or miR-negative control (NC) was detected by realtime fluorescence-based quantitative PCR. The abilities of cell proliferation and migration of EC109 cells transfected with miR-126 mimics were measured by MTT and Transwell assays, respectively. The dual luciferase reporter vectors containing 3'-untranslated region (3'-UTR) with miR-126 binding site of wild type or mutant SOX 2 gene were constructed by using Dual-Luciferase Reporter Assay System, then the relative activity of firefly luciferase was detected to confirm the binding site of miR-126 on SOX 2 gene. The expression levels of SOX2 mRNA and protein in EC109 cells transfected with miR-126 mimics were detected by real-time fluorescence-based quantitative PCR and Western blotting, respectively. The expression of SOX2 protein in esophageal cancer tissues and their paracancerous tissues was examined by immunohistochemistry. Results: The expression level of miR-126 in esophageal cancer tissues was lower than that in paracancerous tissues (P < 0.01), but the expression level of SOX2 mRNA was opposite (P < 0.05). The expression of miR-126 was negatively correlated with the expression of SOX2 (r =-0.837, P < 0.001). After transfection with miR-126 mimics, the expression level of miR-126 in EC109 cells was higher than that in miR-NC group (P < 0.01), but the abilities of cell proliferation and migration were opposite (P < 0.05, P < 0.01). miR-126 can directly target the SOX 2 3'-UTR through two predicted binding sites. The expression levels of SOX2 mRNA and protein in EC109 cells after transfection with miR-126 mimics were lower than those in miR-NC group (P < 0.01). The positive expression rate of SOX2 protein in esophageal cancer tissues was higher than that in paracancerous tissues (P < 0.01). Conclusion: The expression level of miR-126 is lower in esophageal carcinoma tissues, and miR-126 can inhibit the proliferation and migration of EC109 cells, in which SOX 2 may be one of the targeted genes.