从纳米晶到三维超晶格结构

纳米晶的有序组装对未来纳米材料的应用拓展具有重要意义. 本综述介绍了纳米晶三维超晶格的研究价值以及制备方法,着重对“胶体溶液蒸发”、“不良溶剂扩散”、“胶束引导集聚”、“氢键连接”、“静电聚集”、“DNA导向”、“外场辅助”和“水－油界面辅助”的组装机制进行了总结与评述,同时也探讨了这一新兴领域中仍然存在的挑战.     

新课程背景下化学前置作业的编制

一切以学生发展为本的“生本主义”教育理念正逐步深入人心,以编制“前置作业”为突破口的“前置性学习”受到普遍重视。本文简要说明编制前置作业的意义,着重从“生活性”、“针对性”、“实践性”、“开放性”、“层次性”、“真实性”阐述了编制前置作业的策略。     

做科学——《义务教育化学课程标准(2011年版)》基本理念的一点解读

引导学生从“听化学”向“做化学”转变,从“记化学”向“探究化学”转变。学生只有通过“做化学”“探究化学”,在“做科学”的探究实践中培养创新精神和实践能力,科学素养才有可能得到主动地发展。     

基于思维导图发展化学学科核心素养的“醇”教学设计*

基于思维导图架构知识模块,提出“醇”的“六环式”教学模式:“导”“馈”“联”“寻”“攀”“展”。以思维导航、问题学习、讨论活动为教学活动的主线,结合生活化教学情境的创设,由浅入深地探索问题,旨在教学活动中建构和发展化学学科核心素养。     

化学师范生教学设计的评价研究*——以广州市某高校为例

利用化学教学设计评价量表(CTDES),对广州市某高校86名化学师范生在教育实习期间完成的教学设计进行评价,发现师范生在“认知与元认知”“社会文化与情感”“科学描述与应用”指标表现中等,在“一致性”指标表现较好。师范生在对“理论化学”和“描述化学”类课题进行教学设计时,在“认知与元认知”“社会文化与情感”“科学描述与应用”3个指标上的得分存在显著差异。     

基于真实情境的初中化学微项目教学实践与反思*——以“溶液的形成”为例

以“溶液的形成”为例进行微项目教学实践,选择学生熟悉的护手霜为主题情境,巧妙设计了“原料分散”“微观探秘”“辨识活动”“对比实验”“感知乳化”等系列微项目活动,通过情境不断地设置认知冲突,引导学生反思、修正并最终形成更完善的概念,在环环相扣的探究活动中使学生自主建构结构化的知识。通过制作“护手霜”将“溶解”和“乳化”串联,感知溶液,感受乳化,感悟人与自然、社会的和谐、可持续发展。     

初中化学教学中培育社会责任素养*——以“燃料及其利用”复习教学为例

在分析“社会责任”素养内涵和研究现状的基础上,制订了初中化学“燃料及其利用”复习教学课的“社会责任”素养目标,并设计了以“秸秆综合利用的变迁”以及“历史悠久的薪柴燃料-使用方便的化石燃料-清洁环保的新型燃料”的燃料“进化史”为主线的教学流程。从“燃料及其利用”复习教学来看,初中化学教学可以通过真实情境、创新实验和有意义的学习经历等实践路径让学生获得“社会责任”体验,形成“社会责任”素养。     

一次性聚苯乙烯发泡塑料餐具解禁事件及其对化学教学的启示

“一次性聚苯乙烯发泡塑料餐具”在禁用14年之后,近期被国家发展和改革委员会“解禁”,并引起社会的广泛关注和争论。“一次性发泡塑料餐具”问题也是化学教学中经常涉及的“热点”问题之一,因此“解禁”事件也必然会影响到化学教学。结合“一次性发泡塑料餐具”生产的化学工艺流程,分析了其“解禁”原因,探讨了“解禁”事件对化学教学的几点启示。     

生物正交剪切反应及其应用

生物正交反应在化学生物学的研究中发挥着越来越重要的作用.传统的生物正交反应以新化学键生成的连接反应为主,其在实现生物分子的“标记”、“示踪”和“捕捉”等研究中发挥着重要作用.近年来,一类新兴的反应类型--以化学键断裂为基础的生物正交剪切反应逐渐发展起来,并在分子的“释放”、“激活”和“操控”等方面得到了越来越广泛的应用.本文首先重点介绍了生物正交剪切反应,总结了这些反应的特点、适用范围和已经实现的用途.随后通过具体的例子介绍了这些反应在化学生物学中的应用,包括小分子前药的激活、蛋白质功能的调控、细胞的工程化等.最后文章对生物正交剪切反应的发展趋势进行了展望.     

在解密“骗局”中推广化学科普知识*

“骗局”中也蕴含着丰富的化学知识。高校科普工作者可以在解密这些“骗局”中,推广化学科普知识。围绕5W 模式--“谁来科普”“要科普给谁”“如何科普”“科普什么”和“科普效果如何”等5个问题,尝试建立一种在解密“骗局”中推广化学科普知识的新思路。具体为:以青少年和老年人为重点科普对象,构建“老师+学生”共同实施、现场演示与讲解并重、新旧媒体联合传播、“效果指标体系”评价的科普模式,实现精准化学科普的目的。     

Development and Effects of Influenza Antiviral Drugs

Influenza virus is a highly contagious zoonotic respiratory disease that causes seasonal outbreaks each year and unpredictable pandemics occasionally with high morbidity and mortality rates, posing a great threat to public health worldwide. Besides the limited effect of vaccines, the problem is exacerbated by the lack of drugs with strong antiviral activity against all flu strains. Currently, there are two classes of antiviral drugs available that are chemosynthetic and approved against influenza A virus for prophylactic and therapeutic treatment, but the appearance of drug-resistant virus strains is a serious issue that strikes at the core of influenza control. There is therefore an urgent need to develop new antiviral drugs. Many reports have shown that the development of novel bioactive plant extracts and microbial extracts has significant advantages in influenza treatment. This paper comprehensively reviews the development and effects of chemosynthetic drugs, plant extracts, and microbial extracts with influenza antiviral activity, hoping to provide some references for novel antiviral drug design and promising alternative candidates for further anti-influenza drug development.     

Highly sensitive electrochemical immunoassay for H1N1 influenza virus based on copper-mediated amplification

A highly sensitive electrochemical immunoassay method for detection of H1N1 influenza virus with the signal amplification of CuO nanoparticles (NPs) has been demonstrated.     

Facile fabrication of networked patterns and their superior application to realize the virus immobilized networked pattern circuit

A facile route to fabricate a protein-immobilized network pattern circuit for rapid and highly sensitive diagnosis was developed via the evaporation directed impromptu patterning method and selective avian influenza virus (AIV) immobilization. The response to the 10 fg mL(-1) anti-AI antibody demonstrates that this easy and simple circuit has about 1000 times higher sensitivity compared to those of conventional approaches.     

Proximity Ligation‐Based Fluorogenic Imaging Agents for Neuraminidases

Reagents to visualize and localize neuraminidase activity would be valuable probes to study the role of neuraminidases in normal cellular processes as well as during viral infections or cancer development. Herein, a new class of neuraminidase‐imaging probes that function as proximity ligation reagents by releasing a highly reactive fluorophore that tags nearby cellular material is described. It is further demonstrated that it is possible to create an influenza virus‐specific reagent, which can specifically detect influenza virus infections in mammalian cells. These reagents have potential use as specific histological probes independent of viral antigenicity and, therefore, offer some advantages over commonly used anti‐neuraminidase antibodies.     

The evolution and future of influenza pandemic preparedness

The influenza virus is a global threat to human health causing unpredictable yet recurring pandemics, the last four emerging over the course of a hundred years. As our knowledge of influenza virus evolution, distribution, and transmission has increased, paths to pandemic preparedness have become apparent. In the 1950s, the World Health Organization (WHO) established a global influenza surveillance network that is now composed of institutions in 122 member states. This and other surveillance networks monitor circulating influenza strains in humans and animal reservoirs and are primed to detect influenza strains with pandemic potential. Both the United States Centers for Disease Control and Prevention and the WHO have also developed pandemic risk assessment tools that evaluate specific aspects of emerging influenza strains to develop a systematic process of determining research and funding priorities according to the risk of emergence and potential impact. Here, we review the history of influenza pandemic preparedness and the current state of preparedness, and we propose additional measures for improvement. We also comment on the intersection between the influenza pandemic preparedness network and the current SARS-CoV-2 crisis. We must continually evaluate and revise our risk assessment and pandemic preparedness plans and incorporate new information gathered from research and global crises.Subject terms: Influenza virus, Infectious diseases     

Multivalent Peptide–Nanoparticle Conjugates for Influenza-Virus Inhibition

To inhibit binding of the influenza A virus to the host cell glycocalyx, we generate multivalent peptide–polymer nanoparticles binding with nanomolar affinity to the virus via its spike protein hemagglutinin. The chosen dendritic polyglycerol scaffolds are highly biocompatible and well suited for a multivalent presentation. We could demonstrate in vitro that by increasing the size of the polymer scaffold and adjusting the peptide density, viral infection is drastically reduced. Such a peptide–polymer conjugate qualified also in an in vivo infection scenario. With this study we introduce the first non-carbohydrate-based, covalently linked, multivalent virus inhibitor in the nano- to picomolar range by ensuring low peptide-ligand density on a larger dendritic scaffold.     

Novel algorithm for phylogenetic analysis of proteins: application to analysis of the evolution of H5N1 influenza viruses

The highly pathogenic avian influenza virus (HPAIV) A subtype H5N1 is causing threat to human health over the years. Phylogenetic analysis is an important tool for analyzing the evolution of influenza. A novel phylogenetic algorithm based on a new protein distance measure derived from the informational spectrum method (ISM) has been presented. The new phylogenetic approach allows assessment of functional evolution of protein sequences. The new ISM-based phylogenetic approach has been found to overcome some drawbacks of other phylogenetic approaches, particularly concerning sensitivity to a single mutation, deletion and the position of the mutation. The ISM-based approach applied to hemagglutinin subunit 1 protein (HA1) of HPAIV A subtype H5N1 viruses in Egypt between 2006 and 2011, revealed clear clustering in two groups, with one growing group of H5N1 viruses after 2009 with increased number of human infections with H5N1. Four group-specific mutations are identified which are important for increased human tropism and the pandemic potential.     

Inhibition of influenza virus sialidase and anti-influenza virus activity by plant flavonoids

Flavonoids (103 species) were tested for inhibitory activity against influenza virus sialidase using sodium p-nitrophenyl-N-acetyl-alpha-D-neuraminate as substrate. 5,7,4'-Trihydroxy-8-methoxyflavone from the root of Scutellaria baicalensis showed the most potent activity (IC50, 55 microM), and this flavone appeared to be a non-competitive inhibitor of the enzyme. Whereas, negligible or weak inhibitory activities were observed for mouse liver sialidase, beta-galactosidase and alpha-mannosidase as tested. This flavone also inhibited the infection by influenza virus A/PR/8/34 of Madin-Darby canine kidney cells, and replication of the virus in the allantoic sack of embryonated egg. These results suggest that flavone, which has potent influenza virus sialidase inhibitory activity, may have anti-influenza virus activity.     

Pharmacophore Mode lingand Virtual Screening to Design the Potential Influenza Virus Endonuclease Inhibitors

Influenza virus endonuclease is an attractive target for antiviral therapy in the treatment of influenza infection. The purpos e of this study is to design a novel antiviral agent with improved biological activities against the influenza virus endonuclease. In this study, chemical feature‐based 3D pharmacophore models were developed from 41 known influenza virus endonuclease inhibitors. The best quantitative pharmacohore model (Hypo 1), which consists of two hydrogen‐bond acceptors and two hydrophobic features, yields the highest correlation coefficient (R = 0.886). Hypo 1 was further validated by the cross validation method and the test set compounds. The application of this model for predicting the activities of 11 known influenza virus endonuclease inhibitors in the test set shows great success. The correlation coefficient of 0.942 and a cross validation of 95;% confidence level prove that this model is reliable in identifying structurally diverse compounds for influenza virus endonuclease inhibition. The most active compound (compound 1) from the training set was docked into the active site of the influenza virus endonuclease as an additional verification that the pharmacophore model is accurate. The docked conformation showed important hydrogen bond interactions between the compound and two amino acids, Lys 134 and Lys 137. After validation, this model was used to screen the NCI chemical database to identify new influenza virus endonuclease inhibitors. Our study shows that the to pranking compound out of the 10 newly identified compounds using fit value ranking has an estimated activity of 0.049 μM. These newly identified lead compounds can be further experimentally validated using in vitro techniques.