Phytochemical Constituents and Biological Activities of Plants from the Genus Cissampelos

Cissampelos is a significant genus comprising of approximately 21 species of the medicinal plants (Menispermaceae). The plants of this genus are used in traditional medicine for the treatment of various ailments such as asthma, arthritis, dysentery, hyperglycemia, cardiopathy, hypertension and other related problems. These plants are rich in bioactive dibenzylisoquinoline and aborphine as well as small amounts of other ingredients. In recent years, the chemical constituents and pharmacological activities of Cissampelos genus have been paid more and more attention due to their diversity. Herein, we compile the chemical constituents and biological activities on this genus, and summarize the ¹³C-NMR data of the main bioactive ingredients. All information comes from scientific databases such as Google Scholar, PubMed, Sci-Finder, ScienceDirect, Web of Science and CNKI. It provides valuable data for the future research and development of Cissampelos genus.     

Simvastatin augments the efficacy of therapeutic angiogenesis induced by bone marrow-derived mesenchymal stem cells in a murine model of hindlimb ischemia

Many studies showed beneficial effects of either statin or bone marrow-derived mesenchymal stem cells (MSC) treatment in ischemic disease. In an attempt to further improve postischemic tissue repair, we investigated the effect of a local administration of MSC, in the presence or not of low-dose simvastatin, on angiogenesis and functional recovery in a mouse model of hindlimb ischemia. In vitro, the proliferation, migration, apoptosis, and tube formation of bone marrow MSC derived from transgenic mice expressing green fluorescent protein (GFP) were detected in the presence or not of 0.01 μmol/l simvastatin, respectively. In vivo, immediately after hindlimb ischemia, the mice were divided into four groups, namely control, MSC, statin, and statin-MSC, and received a single local injection of MSC (2 × 10⁶ cells) and/or a repeated gavages’ administration of simvastatin (0.2 mg/kg) for 21 days. The blood flow was measured by laser Doppler imaging, the capillary density was detected by alkaline phosphatase staining and, the MSC differentiation was assessed by immunofluorescent staining at 21 days after the ischemia. In vitro, the MSC proliferation rate, migration ability and tube formation number were increased significantly in simvastatin group relative to control group. Whereas, the H₂O₂ induced-apoptosis was inhibited significantly in simvastatin group relative to control group. In vivo, hindlimb blood reperfusion was significantly improved (MSC 0.55 ± 0.08, statin 0.57 ± 0.05, vs. control 0.47 ± 0.07, P < 0.05) and capillary density was obviously higher at day 21 post-ischemia by Laser Doppler Imaging in the MSC group and the Statin group when compared with control group. The combined use of statin and MSC further improved revascularization (perfusion ratio of 0.70 ± 0.09; P < 0.001 verse other groups) and resulted in the highest capillary density (P < 0.05 vs. all other groups). GFP-labeled transplanted cells were more frequently observed in the Statin-MSC group than in the MSC group (6.8 ± 0.5–3.1 ± 0.7, P < 0.05). Low-dose simvastatin could act in a synergistic way with MSC to potentiate the functional neovascularization in a mouse model of hind limb ischemia.     

Influence of Donor Polymer on the Molecular Ordering of Small Molecular Acceptors in Nonfullerene Polymer Solar Cells

Nonfullerene polymer solar cells (PSCs) based on polymer donors and nonfullerene small molecular acceptors (SMAs) have recently attracted considerable attention. Although much of the progress is driven by the development of novel SMAs, the donor polymer also plays an important role in achieving efficient nonfullerene PSCs. However, it is far from clear how the polymer donor choice influences the morphology and performance of the SMAs and the nonfullerene blends. In addition, it is challenging to carry out quantitative analysis of the morphology of polymer:SMA blends, due to the low material contrast and overlapping scattering features of the π–π stacking between the two organic components. Here, a series of nonfullerene blends is studied based on ITIC‐Th blended with five different donor polymers. Through quantitative morphology analysis, the (010) coherence length of the SMA is characterized and a positive correlation between the coherence length of the SMA and the device fill factor (FF) is established. The study reveals that the donor polymer can significantly change the molecular ordering of the SMA and thus improve the electron mobility and domain purity of the blend, which has an overall positive effect that leads to the enhanced device FF for nonfullerene PSCs.     

Sodium Ion Stabilized Vanadium Oxide Nanowire Cathode for High‐Performance Zinc‐Ion Batteries

Aqueous Zn‐ion batteries (ZIBs) have received incremental attention because of their cost‐effectiveness and the materials abundance. They are a promising choice for large‐scale energy storage applications. However, developing suitable cathode materials for ZIBs remains a great challenge. In this work, pioneering work on the designing and construction of aqueous Zn//Na_0.33V₂O₅ batteries is reported. The Na_0.33V₂O₅ (NVO) electrode delivers a high capacity of 367.1 mA h g^?1 at 0.1 A g^?1, and exhibits long‐term cyclic stability with a capacity retention over 93% for 1000 cycles. The improvement of electrical conductivity, resulting from the intercalation of sodium ions between the [V₄O₁₂]_n layers, is demonstrated by single nanowire device. Furthermore, the reversible intercalation reaction mechanism is confirmed by X‐ray diffraction, Raman, X‐ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy analysis. The outstanding performance can be attributed to the stable layered structure and high conductivity of NVO. This work also indicates that layered structural materials show great potential as the cathode of ZIBs, and the indigenous ions can act as pillars to stabilize the layered structure, thereby ensuring an enhanced cycling stability.     

Abscisic acid negatively modulates plant defence against rice black‐streaked dwarf virus infection by suppressing the jasmonate pathway and regulating reactive oxygen species levels in rice

Abscisic acid (ABA) plays a multifaceted role in plant immunity and can either increase resistance or increase susceptibility to some bacterial and fungal pathogens depending on the pathosystem. ABA is also known to mediate plant defence to some viruses. In this study, the relationship between the ABA pathway and rice black‐streaked dwarf virus (RBSDV) was investigated in rice. The expression of ABA pathway genes was significantly reduced upon RBSDV infection. Application of exogenous hormones and various ABA pathway mutants revealed that the ABA pathway plays a negative role in rice defence against RBSDV. Exogenous hormone treatment and virus inoculation showed that ABA inhibits the jasmonate‐mediated resistance to RBSDV. ABA treatment also suppressed accumulation of reactive oxygen species by inducing the expression of superoxidase dismutases and catalases. Thus, ABA modulates the rice–RBSDV interaction by suppressing the jasmonate pathway and regulating reactive oxygen species levels. This is the first example of ABA increasing susceptibility to a plant virus.     

微生物技术“学习情境”项目教学改革探索与实践

针对卫生行业对高职医学生物技术专业人才需求,对接企业就业岗位群,设置微生物技术"学习领域"课程,开发设计来源于企业生产或服务实践的以工作过程为导向的"学习情境"教学单元。强化职业导向,开展理论实践一体化项目教学及云班课互动教学改革。采取多元化考核形式,以产品或项目成果为指引,给学生提供感知和体验工作过程的机会。经过多个学习情境项目教学的长期强化训练,学生积累了适应未来岗位的综合技能和素质。     

Engineering Local Coordination Environments of Atomically Dispersed and Heteroatom‐Coordinated Single Metal Site Electrocatalysts for Clean Energy‐Conversion

Carbon‐based heteroatom‐coordinated single‐atom catalysts (SACs) are promising candidates for energy‐related electrocatalysts because of their low‐cost, tunable catalytic activity/selectivity, and relatively homogeneous morphologies. Unique interactions between single metal sites and their surrounding coordination environments play a significant role in modulating the electronic structure of the metal centers, leading to unusual scaling relationships, new reaction mechanisms, and improved catalytic performance. This review summarizes recent advancements in engineering of the local coordination environment of SACs for improved electrocatalytic performance for several crucial energy‐convention electrochemical reactions: oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, CO₂ reduction reaction, and nitrogen reduction reaction. Various engineering strategies including heteroatom‐doping, changing the location of SACs on their support, introducing external ligands, and constructing dual metal sites are comprehensively discussed. The controllable synthetic methods and the activity enhancement mechanism of state‐of‐the‐art SACs are also highlighted. Recent achievements in the electronic modification of SACs will provide an understanding of the structure–activity relationship for the rational design of advanced electrocatalysts.     

Biogeography of salt marsh plant zonation on the Pacific coast of South America

Aim

The aim of this study was to investigate the biogeography of plant zonation in salt marshes on the Pacific coast of South America; to examine whether salt marsh plant zonation varies with latitude; and to explore the relative importance of climatic, tidal, edaphic and disturbance factors in explaining large‐scale variation in salt marsh plant community structure.

Location

A 2,000‐km latitudinal gradient on the Pacific coast in Chile, with a climate shift from hyper‐arid at low to hyper‐humid at high latitudes.

Methods

Plant zonation was quantified in field surveys of ten marshes. Climate, tidal regimes, edaphic factors and disturbances (tsunami and rainfall floods) were determined. We used multivariate analyses to explore their relative importance in explaining large‐scale variation in salt marsh plant community structure.

Results

Across latitude, marshes were dominated by distinct plant communities in different climate regions, especially at the extreme dry and wet latitudes. Intertidal plant species zonation was present in hyper‐arid and semi‐arid climates, but not in arid, humid and hyper‐humid climates. Latitudinal variation in low‐marsh plant communities (regularly flooded at high tide) was largely a function of precipitation, while at high marshes (never flooded at high tide) latitudinal variation was explained with precipitation, temperature, tidal cycles, soil salinity and disturbances.

Main conclusions

Salt marshes on the Pacific coast of South America belong to Dry Coast and Temperate biogeographic types. Salt marsh plant zonation varies across latitude, and is explained by climatic, tidal, edaphic and disturbance factors. These patterns appear to be mechanistically explained by extrapolating experimentally generated community assembly models and have implications for predicting responses to climate change.