Through quantitative methods,the study evaluates the effectiveness of Web-based Autonomous Learning in College English curriculum reform in a medical college,in order to explore the effect of network autonomous learning on improving medical undergraduates' English listening and speaking ability.The study shows that in four-semester College English learning,by urging students to carry out autonomous listening and speaking based on network and computer and adopting the in class + after class learning mode,the students' English listening and speaking ability has been improved,and their interest in learning has also been enhanced.However,students' emotional factor and curriculum design have great influence on online autonomous learning in the Curriculum Reform.

Aim To study the effects of Procyanidins (PC) on apoptosis of PC12 cells induced by A? 25-35. Methods Cell survival rate was evaluated by MTT assay, and apoptosis was analyzed by Hoechst-PI fluorescence staining. The expressions of mRNA and protein for P53 and Bcl-2 were tested by RT-PCR and Western blot. Results Pretreatment with different concentrations of PC (10~30 mg?L -1) for 1h increased the survival rate of PC12 cells in a dose-dependent fashion. PC prevented the PC12 cells nuclei from shrinkage, condensation and cleavage induced by A? 25-35. PC decreased the expressions of P53 mRNA and P53 protein, and increased the expression of bcl-2 mRNA and Bcl-2 protein. Conclusion These results indicated that PC can protect PC12 cells from apoptosis induced by A? 25-35. The mechanism of protection is likely related to decreasing P53 gene expression, and increasing bcl-2 gene expression.

Objective To study the effect of procyanidins (PC) on mRNA and protein expression of par-4 and bcl-2 genes in PC12 cells induced by A?_ 25-35 . Methods Cell survival rate was evaluated by MTT assay and apoptosis was analyzed by Hoechst 33258-PI fluorescence staining. The expressions of mRNA and protein for par-4 and bcl-2 were tested by RT-PCR and Western blotting. Results Pretreatment with different concentrations of PC (5、10、20, and 30 mg/L) for 1 h increased the survival rate of PC12 cell in a dose-dependent manner. PC prevented the PC12 cells nuclei from shrinkage, condensation, and cleavage induced by A?_ 25-35 . PC decreased the expression of par-4 mRNA and protein, and increased the expression of bcl-2 mRNA and protein. Conclusion PC can protect PC12 cells from apoptosis induced by A?_ 25-35 in a dose dependent manner. The mechanism of protection is likely related to decreasing the par-4 gene expression and increasing the bcl-2 gene expression.

Objective To explore the curative effect of tirofiban treatment on high-risk acute coronary syndromes (ACS) in elderly patients receiving an early percutaneous coronary intervention (PCI) treatment. Methods The 162 elderly cases including unstable angina pectoris and non-ST -segment elevation myocardial infarction (NSTEMI) undergoing early PCI were enrolled in this study.And they were assigned to early treatment group (n=82) and deferred selective group (n=80)according to the time of using tirofiban (Gp Ⅱ b/Ⅲ a inhibitor) treatment. The effectiveness of either strategic option on tissue-level perfusion was evaluated using the TIMI myocardial perfusion grade (TMPG) before and immediately after PCI. The corrected TIMI frame count (cTFC) was also used to assess coronary artery flow and myocardial perfusion. Bleeding complications and the composite end point events at 30 days were also evaluated. Results Of all the 162 patients, the TMPG 0-1 perfusion was observed in 65 patients (40.1%). The TMPG 0-1 perfusion was significantly less frequent in early treatment group (32.9%) than in deferred selective group (47.5%) before PCI (x2=3.58, P＜0.05); while the results of TIMI grade 0-1 flow (26.8% vs. 25.0%) and cTFC levels (34.2±11.8 vs. 34. 9±12. 7) before PCI were similar between the two groups (x2 =0. 07, P=0.47; t= 0.13, P=0.71, respectively). No differences were seen both in composite end point events at 30 days and bleeding complications (x2 = 0.31, P＞0.05; x2=0.004, P＞0. 05). Conclusions High -risk ACS patients treated with an early invasive strategy, routine upstream use of tirofiban are associated with improved tissue-level perfusion before PCI and does not increase bleeding complications when bleeding risks are carefully evaluated before enrollment.

OBJECTIVE: To optimize the induction condition of human NOR1 gene expression in E.coli. and purify NOR1 recombinant proteins. METHODS: A full-length cDNA of human NOR1 was inserted into the corresponding region of pET28b expression vector to yield recombinant prokaryotic expression vector pET28b-NOR1. The prokaryotic expression vector pET28b-NOR1 was introduced into the bacterial host E.coli Rosettablue(DE3). Recombinant NOR1 protein was induced at different conditions. Induction condition was optimized to obtain high yield of recombinant protein. At last, the recombinant NOR1 protein was purified by Ni-IDE chromatography resin. RESULTS: Recombinant NOR1 protein was induced by IPTG in a dose-dependent manner. Increase of kanamycin concentration and induction temperature resulted in high yield of recombinant protein. The most recombinant protein was found in inclusion bodies. The recombinant His-NOR1 protein was purified with Ni-IDE chromatography resin under denature condition. CONCLUSION IPTG, kanamycin concentration and temperature can affect the expression of recombinant NOR1 protein in pET28b system. High yield of recombinant NOR1 protein is achieved by inducing 1 mmol/L IPTG and 200 μg/mL kanamycin at 37 degree. Recombinant His-NOR1 protein with high purity is purified.
Base Sequence ; Escherichia coli ; genetics ; metabolism ; Genetic Vectors ; Humans ; Isopropyl Thiogalactoside ; pharmacology ; Membrane Transport Proteins ; biosynthesis ; genetics ; Molecular Sequence Data ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Tumor Suppressor Proteins ; biosynthesis ; genetics

Coculture between mesenchymal stem cells (MSCs) and chondrocytes has significant implications in cartilage regeneration. However, a conclusive understanding remains elusive. Previously, we reported that rabbit bone marrow-derived MSCs (rbBMSCs) could downregulate the differentiated phenotype of rabbit articular chondrocytes (rbACs) in a non-contact coculture system for the first time. In the present study, a systemic investigation was performed to understand the biological characteristics of chondrocytes in coculture with MSCs. Firstly, cells (MSCs and chondrocytes) from different origins were cocultured in transwell system. Different chondrocytes, when cocultured with different MSCs respectively, consistently demonstrated stimulated proliferation, transformed morphology and declined glycosaminoglycan secretion of chondrocytes. Next, cell surface molecules and the global gene expression of rbACs were characterized. It was found that cocultured rbACs showed a distinct surface molecule profile and global gene expression compared to both dedifferentiated rbACs and rbBMSCs. In the end, cocultured rbACs were passaged and induced to undergo the chondrogenic redifferentiation. Better growth and chondrogenesis ability were confirmed compared with control cells without coculture. Together, chondrocytes display comprehensive changes in coculture with MSCs and the cocultured rbACs are beneficial for cartilage repair.
Cartilage ; Chondrocytes ; Chondrogenesis ; Coculture Techniques ; Gene Expression ; Mesenchymal Stromal Cells ; Phenotype ; Population Characteristics ; Regeneration

The family of voltage-gated potassium Kv2 channels consists of the Kv2.1 and Kv2.2 subtypes. Kv2.1 is constitutively highly phosphorylated in neurons and its function relies on its phosphorylation state. Whether the function of Kv2.2 is also dependent on its phosphorylation state remains unknown. Here, we investigated whether Kv2.2 channels can be phosphorylated by protein kinase C (PKC) and examined the effects of PKC-induced phosphorylation on their activity and function. Activation of PKC inhibited Kv2.2 currents and altered their steady-state activation in HEK293 cells. Point mutations and specific antibodies against phosphorylated S481 or S488 demonstrated the importance of these residues for the PKC-dependent modulation of Kv2.2. In layer II pyramidal neurons in cortical slices, activation of PKC similarly regulated native Kv2.2 channels and simultaneously reduced the frequency of action potentials. In conclusion, this study provides the first evidence to our knowledge that PKC-induced phosphorylation of the Kv2.2 channel controls the excitability of cortical pyramidal neurons.
Action Potentials ; HEK293 Cells ; Humans ; Protein Kinase C/metabolism* ; Pyramidal Cells/enzymology* ; Shab Potassium Channels/genetics*

As a group of nonspecific inflammatory diseases affecting the intestine, inflammatory bowel disease (IBD) exhibits the characteristics of chronic recurring inflammation, and was proven to be increasing in incidence (Kaplan, 2015). IBD induced by genetic background, environmental changes, immune functions, microbial composition, and toxin exposures (Sasson et al., 2021) primarily includes ulcerative colitis (UC) and Crohn's disease (CD) with complicated clinical symptoms featured by abdominal pain, diarrhea, and even blood in stools (Fan et al., 2021; Huang et al., 2021). UC is mainly limited to the rectum and the colon, while CD usually impacts the terminal ileum and colon in a discontinuous manner (Ordás et al., 2012; Panés and Rimola, 2017). In recent years, many studies have suggested the lack of effective measures in the diagnosis and treatment of IBD, prompting an urgent need for new strategies to understand the mechanisms of and offer promising therapies for IBD.
Chronic Disease ; Colitis, Ulcerative/therapy* ; Crohn Disease/epidemiology* ; Diarrhea ; Homeodomain Proteins ; Humans ; Inflammatory Bowel Diseases ; Mesenchymal Stem Cells/cytology* ; MicroRNAs ; RNA, Long Noncoding ; Recurrence ; Umbilical Cord/cytology*