85 research outputs found

    Constructivist Perspective on Developing a Multidimensional Blended Teaching Model Fostering Deep Learning

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    To promote high-quality development of higher education, it is imperative to facilitate students’ transition from surface learning to deep learning. Compared with surface learning that focuses on rote memorization, deep learning emphasizes meaningful learning based on understanding and transfer. It involves three progressively advanced cognitive stages of knowing: "learning for understanding," "learning for application," and "learning for innovation," which ultimately enable the internalization, transfer, and creative application of knowledge. How to foster deep learning in students has been an urgent issue of higher education. This study, grounded in constructivist learning theory, explores a multidimensional blended teaching model fostering deep learning. It also develops an evaluation system assessing learning outcomes from the perspectives of ideological, political and moral education, knowledge, and competencies. We conducted an empirical study to test the effectiveness of this multidimensional blended teaching model. Findings will provide theoretical and practical implications for teaching reforms of similar courses

    IL28B is associated with outcomes of chronic HBV infection

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    Purpose The role of IL28B gene variants and expression in hepatitis B virus (HBV) infections are not well understood. Here, we evaluated whether IL28B gene expression and rs12979860 variations are associated with HBV outcomes. Materials and Methods IL28B genetic variations (rs12979860) were genotyped by pyrosequencing of DNA samples from 137 individuals with chronic HBV infection [50 inactive carriers (IC), 34 chronic hepatitis B (CHB), 27 cirrhosis, 26 hepatocellular carcinoma (HCC)], and 19 healthy controls. IL28A/B mRNA expression in peripheral blood mononuclear cells was determined by qRT-PCR, and serum IL28B protein was measured by ELISA. Results Patients with IL28B C/C genotype had greater IL28A/B mRNA expression and higher IL28B protein levels than C/T patients. Within the various disease stages, compared to IC and healthy controls, IL28B expression was reduced in the CHB, cirrhosis, and HCC cohorts (CHB vs. IC, p=0.02; cirrhosis vs. IC, p=0.01; HCC vs. IC, p=0.001; CHB vs. controls, p&#60;0.01; cirrhosis vs. controls, p&#60;0.01; HCC vs. controls, p&#60;0.01). When stratified with respect to serum HBV markers in the IC and CHB cohorts, IL28B mRNA and protein levels were higher in HBeAg-positive than negative individuals (p=0.01). Logistic regression analysis revealed that factors associated with high IL28B protein levels were C/C versus C/T genotype [p=0.016, odds ratio (OR)=0.25, 95% confidence interval (CI)=0.08-0.78], high alanine aminotransferase values (p&#60;0.001, OR=8.02, 95% CI=2.64-24.4), and the IC stage of HBV infection (p&#60;0.001). Conclusion Our data suggest that IL28B genetic variations may play an important role in long-term development of disease in chronic HBV infections.</p

    Plastid-nucleus communication involves calcium-modulated MAPK signalling

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    Chloroplast retrograde signals play important roles in coordinating the plastid and nuclear gene expression and are critical for proper chloroplast biogenesis and for maintaining optimal chloroplast functions in response to environmental changes in plants. Until now, the signals and the mechanisms for retrograde signalling remain poorly understood. Here we identify factors that allow the nucleus to perceive stress conditions in the chloroplast and to respond accordingly by inducing or repressing specific nuclear genes encoding plastid proteins. We show that ABI4, which is known to repress the LHCB genes during retrograde signalling, is activated through phosphorylation by the MAP kinases MPK3/MPK6 and the activity of these kinases is regulated through 14-3-3 omega-mediated Ca2+-dependent scaffolding depending on the chloroplast calcium sensor protein CAS. These findings uncover an additional mechanism in which chloroplast-modulated Ca2+ signalling controls the MAPK pathway for the activation of critical components of the retrograde signalling chain

    Plastid-nucleus communication involves calcium-modulated MAPK signalling

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    Chloroplast retrograde signals play important roles in coordinating the plastid and nuclear gene expression and are critical for proper chloroplast biogenesis and for maintaining optimal chloroplast functions in response to environmental changes in plants. Until now, the signals and the mechanisms for retrograde signalling remain poorly understood. Here we identify factors that allow the nucleus to perceive stress conditions in the chloroplast and to respond accordingly by inducing or repressing specific nuclear genes encoding plastid proteins. We show that ABI4, which is known to repress the LHCB genes during retrograde signalling, is activated through phosphorylation by the MAP kinases MPK3/MPK6 and the activity of these kinases is regulated through 14-3-3 omega-mediated Ca2+-dependent scaffolding depending on the chloroplast calcium sensor protein CAS. These findings uncover an additional mechanism in which chloroplast-modulated Ca2+ signalling controls the MAPK pathway for the activation of critical components of the retrograde signalling chain

    Hepatitis B virus–induced imbalance of inflammatory and antiviral signaling by differential phosphorylation of STAT1 in human monocytes

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    It is not clear how hepatitis B virus (HBV) modulates host immunity during chronic infection. In addition to the key mediators of inflammatory response in viral infection, monocytes also express a high-level IFN-stimulated gene, CH25H, upon response to IFN-a exerting an antiviral effect. In this study, the mechanism by which HBV manipulates IFN signaling in human monocytes was investigated. We observed that monocytes from chronic hepatitis B patients express lower levels of IFN signaling/stimulated genes and higher levels of inflammatory cytokines compared with healthy donors. HBV induces monocyte production of inflammatory cytokines via TLR2/MyD88/NF-kB signaling and STAT1-Ser727 phosphorylation and inhibits IFN-a–induced stat1, stat2, and ch25h expression through the inhibition of STAT1-Tyr701 phosphorylation and in an IL-10–dependent, partially autocrine manner. Further, we found that enhancement of STAT1 activity with a small molecule (2-NP) rescued HBV-mediated inhibition of IFN signaling and counteracted the induction of inflammatory cytokines. In conclusion, HBV contributes to the monocyte inflammatory response but inhibits their IFN-a/b responsiveness to impair antiviral innate immunity. These effects are mediated via differential phosphorylation of Tyr701 and Ser727 of STAT1

    Hepatitis C virus core protein triggers expansion and activation of CD4+CD25+ regulatory T cells in chronic hepatitis C patients

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    CD4+CD25+FoxP3+ regulatory T cells (Tregs) are increased in patients with chronic hepatitis C, which may contribute to the sustained suppression of hepatitis C virus (HCV)-specific T-cell responses and viral persistence in HCV-infected individuals. We postulated that HCV core protein (HCVc) directly contributes to the expansion of Tregs in HCV-infected patients, and we provide evidence to support this hypothesis in the report. Peripheral blood mononuclear cells (PBMCs) and sera were collected from 87 treatment-naïve chronic HCV-infected patients, CD4+CD25+ Tregs were measured by flow cytometry, and HCV RNA and HCVc levels were detected using qPCR and enzyme-linked immunosorbent assay (ELISA), respectively. CD4+, CD8+, CD4+CD25+ and CD4+CD25− T cells were purified from healthy donors and cultured with recombinant HCVc and Toll-like receptor (TLR) ligands. Flow cytometry was used to analyze cell proliferation, and ELISA was performed to measure cytokine production. In the 87 chronic HCV-infected patients, HCVc showed a significant correlation with HCV RNA and CD4+CD25+ Tregs. Mechanistic studies showed that HCVc, together with anti-CD3 antibody, augmented CD4+CD25+ Treg proliferation, but inhibited CD4+CD25− T-cell proliferation and IFN-γ production, in a dose-dependent and Treg-dependent manner. Moreover, unlike the TLR3 ligand (poly I:C) and the TLR4 ligand (lipopolysaccharide, LPS), the TLR2 ligand (lipoteichoic acid, LTA) and HCVc both inhibited TCR-induced CD4+ T-cell proliferation and IFN-γ secretion in a Treg-dependent manner. These data indicate that HCVc, like other TLR2 ligands, triggers CD4+CD25+ Treg activation and expansion to inhibit host immune responses, which may play a critical role in viral persistence in HCV-infected patients

    IL28B Genetic Variation Is Associated with Spontaneous Clearance of Hepatitis C Virus, Treatment Response, Serum IL-28B Levels in Chinese Population

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    &lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; The interleukin-28B gene (IL28B) locus has been associated with host resistance to hepatitis C virus (HCV) infection and response to PEG-IFN/RBV treatment in western populations. This study was to determine whether this gene variant is also associated with spontaneous clearance of HCV infection, treatment response and IL-28B protein production in Chinese patients.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methods:&lt;/b&gt; We genotyped IL28B genetic variations (rs12980275, rs8103142, rs8099917 and rs12979860) by pyrosequencing DNA samples from cohorts consisting of 529 subjects with persistent HCV infection, 196 subjects who cleared the infection, 171 healthy individuals and 235 chronic HCV patients underwent IFN/RBV treatment. The expression of IL-28B were measured by ELISA and RT-PCR.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Results:&lt;/b&gt; We found that the four IL28B variants were in complete linkage disequilibrium (r2 = 0.97–0.98). The rs12979860 CC genotype was strongly associated with spontaneously HCV clearance and successful IFN/RBV treatment compared to the CT/TT. IL-28B levels in persistent HCV patients were significantly lower than subjects who spontaneously resolved HCV and healthy controls and were also associated with high levels of ALT (alanine aminotransferase) and AST (aspartate aminotransferase). IL-28B levels were also significantly lower in individuals carrying T alleles than CC homozygous.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions:&lt;/b&gt; Thus, the rs12979860-CC variant upstream of IL28B gene is associated with spontaneous clearance of HCV, susceptible to IFN/RBV treatment and increased IL-28B levels in this Chinese population.&lt;/p&gt

    Epidemiological screening and detection indicators for hepatitis D and suitable populations

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    Hepatitis D virus (HDV) infection requires the participation of hepatitis B virus (HBV), which accelerates disease progression after infection and induces a high risk of progression to end-stage liver diseases such as liver cirrhosis and liver cancer. With the gradual increase in the understanding of hepatitis D in the whole society, some therapeutic drugs for hepatitis D have become a research hotspot in recent years, and with the further improvement in clinical testing methods, researchers have started to pay attention to the epidemiological investigation of hepatitis D. Although many studies have been conducted for the specific situation of HDV infection in China, large data deviation is observed due to small cohorts with strong regional features. This article briefly reviews the population, methods, and indicators in the current epidemiological investigation of hepatitis D and discusses related key issues, in order to obtain more accurate epidemiological data, effectively screen out HDV infection, and provide help for early clinical intervention and treatment
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