Drought stress is a major threat to crop production, but effective methods to mitigate the adverse effects of drought are not available. Here, we report that adding fluorine atoms in the benzyl ring ...of the abscisic acid (ABA) receptor agonist AM1 optimizes its binding to ABA receptors by increasing the number of hydrogen bonds between the compound and the surrounding amino acid residues in the receptor ligand-binding pocket. The new chemicals, known as AMFs, have long-lasting effects in promoting stomatal closure and inducing the expression of stress-responsive genes. Application of AMFs or transgenic overexpression of the receptor PYL2 in Arabidopsis and soybean plants confers increased drought resistance. The greatest increase in drought resistance is achieved when AMFs are applied to the PYL2-overexpression transgenic plants. Our results demonstrate that the combining of potent chemicals with transgenic overexpression of an ABA receptor is very effective in helping plants combat drought stress.
Light‐inducible approaches provide a means to control biological systems with spatial and temporal resolution that is unmatched by traditional genetic perturbations. Recent developments of ...optogenetic and chemo‐optogenetic systems for induced proximity in cells facilitate rapid and reversible manipulation of highly dynamic cellular processes and have become valuable tools in diverse biological applications. New expansions of the toolbox facilitate control of signal transduction, genome editing, “painting” patterns of active molecules onto cellular membranes, and light‐induced cell cycle control. A combination of light‐ and chemically induced dimerization approaches have also seen interesting progress. Herein, an overview of optogenetic systems and emerging chemo‐optogenetic systems is provided, and recent applications in tackling complex biological problems are discussed.
Proteins under the spotlight: Various optogenetic systems that involve photosensitive proteins are summarized and emerging chemo‐optogenetic systems with caged or photocleavable chemical dimerizers are reviewed (see figure). The advantages and disadvantages of these systems are discussed. Recent biological applications of these strategies are presented.
Phenols are widely used as starting materials in both industrial and academic society. Dearomatization reactions of phenols provide an efficient way to construct highly functionalized ...cyclohexadienones. The main challenge to make them asymmetric by catalytic methods is to control the selectivity while overcoming the loss of aromaticity. In this tutorial review, an up to date summary of recent progress in CADA reactions of phenol and aniline derivatives is presented.
In this tutorial review, an up to date summary of recent progress in catalytic asymmetric dearomatization (CADA) reactions of phenol and aniline derivatives is presented.
In recent years, with the acceleration of life rhythm and increased pressure, the problem of sleep disorders has become more and more serious. It affects people's quality of life and reduces work ...efficiency, so the monitoring and evaluation of sleep quality is of great significance. Sleep staging has an important reference value in sleep quality assessment. This article starts with the study of sleep staging to detect and analyze sleep quality. For the purpose of sleep quality detection, this article proposes a sleep quality detection method based on electroencephalography (EEG) signals.
This method first preprocesses the EEG signals and then uses the discrete wavelet transform (DWT) for feature extraction. Finally, the transfer support vector machine (TSVM) algorithm is used to classify the feature data.
The proposed algorithm was tested using 60 pieces of data from the National Sleep Research Resource Library of the United States, and sleep quality was evaluated using three indicators: sensitivity, specificity, and accuracy. Experimental results show that the classification performance of the TSVM classifier is significantly higher than those of other comparison algorithms. This further validated the effectiveness of the proposed sleep quality detection method.
High‐performance MoS2 transistors are developed using atomic hexagonal boron nitride as a tunneling layer to reduce the Schottky barrier and achieve low contact resistance between metal and MoS2. ...Benefiting from the ultrathin tunneling layer within 0.6 nm, the Schottky barrier is significantly reduced from 158 to 31 meV with small tunneling resistance.
Dispersed H3K27 trimethylation (H3K27me3) of the AGAMOUS (AG) genomic locus is mediated by CURLY LEAF (CLF), a component of the Polycomb Repressive Complex (PRC) 2. Previous reports have shown that ...the AG second intron, which confers AG tissue-specific expression, harbors sequences targeted by several positive and negative regulators.
Using RACE reverse transcription polymerase chain reaction, we found that the AG intron 2 encodes several noncoding RNAs. RNAi experiment showed that incRNA4 is needed for CLF repressive activity. AG-incRNA4 RNAi lines showed increased leaf AG mRNA levels associated with a decrease of H3K27me3 levels; these plants displayed AG overexpression phenotypes.
Genetic and biochemical analyses demonstrated that the AG-incRNA4 can associate with CLF to repress AG expression in leaf tissues through H3K27me3-mediated repression and to autoregulate its own expression level.
The mechanism of AG-incRNA4-mediated repression may be relevant to investigations on tissue-specific expression of Arabidopsis MADS-box genes.
The coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2 virus) has been sustained in China since December 2019, and has become a ...pandemic. The mental health of frontline medical staff is a concern. In this study, we aimed to identify the factors influencing medical worker anxiety in China during the COVID-19 outbreak. We conducted a cross-sectional study to estimate the prevalence of anxiety among medical staff in China from 10 February 2020 to 20 February 2020 using the Zung Self-rating Anxiety Scale (SAS) to assess anxiety, with the criteria of normal (⩽49), mild (50-59), moderate (60-70) and severe anxiety (⩾70). We used multivariable linear regression to determine the factors (e.g. having direct contact when treating infected patients, being a medical staff worker from Hubei province, being a suspect case) for anxiety. We also used adjusted models to confirm independent factors for anxiety after adjusting for gender, age, education and marital status. Of 512 medical staff in China, 164 (32.03%) had had direct contact treating infected patients. The prevalence of anxiety was 12.5%, with 53 workers suffering from mild (10.35%), seven workers suffering from moderate (1.36%) and four workers suffering from severe anxiety (0.78%). After adjusting for sociodemographic characteristics (gender, age, education and marital status), medical staff who had had direct contact treating infected patients experienced higher anxiety scores than those who had not had direct contact (β value = 2.33, confidence interval (CI) 0.65-4.00; P = 0.0068). A similar trend was observed in medical staff from Hubei province, compared with those from other parts of China (β value = 3.67, CI 1.44-5.89; P = 0.0013). The most important variable was suspect cases with high anxiety scores, compared to non-suspect cases (β value = 4.44, CI 1.55-7.33; P = 0.0028). In this survey of hospital medical workers during the COVID-19 outbreak in China, we found that study participants experienced anxiety symptoms, especially those who had direct clinical contact with infected patients; as did those in the worst affected areas, including Hubei province; and those who were suspect cases. Governments and healthcare authorities should proactively implement appropriate psychological intervention programmes, to prevent, alleviate or treat increased anxiety.
There is much interest in the use of extracellular vesicles (EVs) as a subcellular therapy for regenerative medicine and drug delivery. Blood-borne platelets represent a source of therapeutic EVs ...that is so far largely unexplored. Advantages of platelets as a cellular source of EVs include their established clinical value, regulated collection procedures, availability in a concentrated form, propensity to generate EVs, and unique composition and tissue-targeting capacity. This review analyzes the unique potential of platelet-derived (p-) EVs as therapeutic modalities and presents their inherent translational advantages for hemostasis, for regenerative medicine, and as drug-delivery vehicles.
Platelet concentrates are a licensed medicinal cellular product for hospital-based transfusion and are used as raw materials to prepare platelet lysates for human cell propagation.Platelet concentrates can be used to generate platelet-derived extracellular vesicles (p-EVs) for novel therapeutic indications in regenerative medicine and as drug-delivery vehicles.Using platelets as a source of EVs can alleviate the industrial and regulatory challenges associated with EVs generated from in vitro-expanded mesenchymal stromal cells.Procedures are under development to define downstream industrial manufacturing processes, pathogen safety measures, quality controls, and release criteria for p-EVs.Research and industrial collaborations among blood establishments, the biotech and cell therapy industries, bioindustry suppliers, and regulators are vital to accelerate clinical translation.
With the rapid development of the global economy, the depletion of fossil fuels and the intensification of environmental pollution, there is an increasingly urgent need for new and green ...electrochemical energy storage technologies in society. In this thesis, ligninsulfonate/polyaniline nanocomposites were synthesized by
in situ
chemical oxidation using aniline as the monomer, lignin as the template and dopant, and ammonium persulfate as the oxidant. The results showed that the average diameter of the ligninsulfonate/polyaniline nanocomposite was 85 nm, and the composite electrode exhibited good electron conduction ability and excellent capacitive performance by ligninsulfonate doping. The electrode material showed the best electrochemical performance when the ligninsulfonate addition was 0.1 g. The specific capacitance can reach 553.7 F g
1
under the current density of charge/discharge 1 A g
1
, which is higher than that of the pure PANI electrode. The composite electrode material has good multiplicative performance and cycling stability, and the capacitance retention rate can be maintained at 68.01% after 5000 cycles at a charge/discharge current density of 10 A g
1
(three-electrode system), and the capacitance retention rate can be maintained at 54.84% after 5000 cycles at a charge/discharge current density of 5 A g
1
(two-electrode system).
The lignosulfonate/polyaniline nanocomposite electrode material was made by polymerization of aniline with lignosulfonate as dispersant and structure-directing agent. Redox can convert the catechol/quinone groups on lignin, promoted by electron transfer of polyaniline.
The current strategies for nanoelectrode functionalization usually involve sophisticated modification procedures, uncontrollable and unstable modifier assembly, as well as a limited variety of ...modifiers. To address this issue, we propose a versatile strategy for large‐scale synthesis of biomimetic molecular catalysts (BMCs) modified nanowires (NWs) to construct functionalized electrochemical nanosensors. This design protocol employs an easy, controllable and stable assembly of diverse BMCs‐poly(3,4‐ethylenedioxythiophene) (PEDOT) composites on conductive NWs. The intrinsic catalytic activity of BMCs combined with outstanding electron transfer ability of conductive polymer enables the nanosensors to sensitively and selectively detect various biomolecules. Further application of sulfonated cobalt phthalocyanine functionalized nanosensors achieves real‐time electrochemical monitoring of intracellular glutathione levels and its redox homeostasis in single living cells for the first time.
Versatile and large‐scale synthesis of biomimetic molecular catalyst modified nanowires provides an innovative perspective for simple and stable construction of functionalized electrochemical nanosensors. Such nanosensors enable the sensitive and selective detection of diverse biomolecules, and for the first time achieve real‐time electrochemical monitoring of intracellular glutathione levels and its redox homeostasis in single living cells.
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