Current Chinese Science - Volume 2, Issue 5, 2022

Background: Restrained by the aggregation-causing quenching of conventional fluorophores, the design and synthesis of solid-state emissive materials is a persistent pursuit for scientists. The discovery of aggregation-induced emission provides an efficient strategy for preparing solidstate emissive luminogens. Objective: A multifunctional solid-state emissive material DMBTPE was prepared from tetraphenylethylene and N-methylated barbituric acid through the construction of donor-acceptor structure. Methods: DMBTPE showed typical aggregation-induced emission characteristics: non-emissive when molecularly dissolved in solution while strongly emissive in the aggregated state or as solid. Owing to the strong donor-acceptor interaction, the maximum absorption of DMBTPE shifted to the visible light region. DMBTPE also exhibited reversible mechanochromic fluorescence with 30-40 nm emission wavelength change. Results: DSC and XRD results indicated the transition between the amorphous state and crystalline state was accounted for the mechanochromic fluorescence behavior. The microcrystalline rods of DMBTPE grown from hot ethanol solution exhibited good optical waveguiding effect and the optical loss was as low as 0.018 dB/μm. Conclusion: DMBTPE was an efficient solid emitter. Such attributes enable this kind of materials to find wide applications in many areas, such as biological imaging and optoelectronic devices.

Background: Perovskite glass-ceramics have attracted the attention of researchers and scientists due to their wide range of applications in energy storage devices, solar cells, photovoltaic cells, etc. Barium titanate is the first discovered perovskite glass-ceramics. After the discovery of barium titanate, several perovskite glass-ceramics have been discovered. Several substitutions have also been attempted for the progress of perovskites. Barium strontium titanate is one of the perovskite glass-ceramics in which few barium ions are replaced by strontium ions. The crystal clamping is also found in a few perovskite glass-ceramics, e.g., PbTiO3. Aims: In the present investigation, our focus is on the synthesis and crystallization behavior of barium strontium titanate borosilicate glass-ceramics in glass system 64[(Ba1-xSrx).TiO3]- 30[2SiO2.B2O3]-5[K2O]-1[La2O3] (0.0 ≤ x ≤ 1.0). Methods: Synthesized glasses were characterized by differential thermal analysis, X-ray diffraction, and scanning electron microscopy. Results: The crystallization behavior showed the formation of major crystalline phase of BaTiO3/ BaSrTiO3/ Ba1.91Sr0.09TiO4/ SrTiO3 along with some pyrochlore phase of Ba2TiSi2O8/ Sr2TiSi2O8/ Ba2Ti2B2O9/ Sr2B2O5. The crystalline phase formation depends upon both composition and the crystallization process. The crystal clamping was attributed to synthesizing glass-ceramics samples during the crystallization. Conclusion: Bulk barium strontium titanate glass-ceramics were successfully prepared by the melt quench method. X-ray diffraction studies confirmed the formation of the major perovskite phase. During the crystallization of glasses, crystal clamping is attributed to the barium strontium titanate glass-ceramics.

Background: This study aims at exploring the advances in data repositories for predicting interactions between non-coding RNAs (ncRNAs) and corresponding proteins. NcRNAs are a class of ribonucleic acid that lacks the potential for protein translation. A series of studies indicated that ncRNAs play critical roles in epigenetic regulations, chromatin remodeling, transcription process, and post-transcriptional processing. Since ncRNAs function with associated proteins during complex biological procedures, it is important to identify ncRNA-protein interactions, which will provide guidance for exploring the internal molecular mechanisms. Recently, a variety of machine learning methods have emerged, with the lower cost and time-saving advantages compared to experimental methods. In machine learning, the performance of classification models is often affected by the quality of input samples and their features. Aims: Thus, the study intends to introduce the related data sources used in predicting ncRNAprotein interactions (ncRPIs) based on machine learning. Methods: We searched related literature from different sources, including PubMed, Web of Science, and Scopus, using the search terms “machine learning”, “repository”, “non-coding RNA”, and “protein”. In this work, we described the databases applied to the dataset construction and feature representation in the ncRPIs prediction task. Results: This study reviews the application of the benchmark dataset construction and conventional feature representation during ncRPI prediction processes. Furthermore, the source, main functions, and development status of each database are also discussed in this work. Conclusion: With the development of high-throughput technologies for generating ncRPIs and constructing related databases, machine learning would become a necessary research means, enriching the prediction methods of ncRPIs. Due to an increase in improved databases, the resources of molecular structures, functions, and genetic information for data mining have increased, enhancing the credibility of ncRPI prediction based on machine learning. We believe that the databases will be more widely used in disease research, drug development, and many other fields.

Background: Adathoda vasica is the most well-known medicinal herb to treat respiratory conditions. The leaves of Adathoda vasica have been found to exert a stimulant effect on the respiratory system. Adathoda vasica leaves contain rich content of alkaloids that contribute to most of the pharmacological activity. Objective: This study aimed to evaluate the effectiveness of Adathoda vasica extract against the respiratory pathogen Klebsiella pneumoniae in vivo and an animal model. Methods: The effectiveness of the A. vasica extracts to inhibit the chief respiratory pathogen, K. pneumoniae, in vivo using CFU assay was carried out in animal models. The bioactive compounds were screened through GC-MS and were docked with FIMG protein and COVID-19 proteins to assess the efficacy of the compounds against respiratory infection. Results: The result revealed A. vasica as an effective herb against respiratory infection. The ethanol extract of A. vasica was subjected to GC-MS analysis. Based on the percentage of peak area, three compounds were chosen for docking analysis for FIMG and SARS-CoV-2 proteins, which revealed higher binding affinity and interacted with the residues. The greater ZOI by disc diffusion assay and reduced CFU in plant-treated rat lung tissues confirmed the antibacterial potential of A. vasica against K. pneumoniae. Conclusion: The bioactive compounds of A. vasica leaves could be promising candidates to treat respiratory infections caused by K. pneumoniae.

Environmental stresses adversely impact crop production, crop quality, and product safety. Climate change is predicted to exacerbate the impacts of stresses on current cropping systems with multilateral impacts on crop productivity and yield, biodiversity, soil fertility, microbial activity, and carbon sequestration. Transforming crop production systems and developing stress and climate- resilient crops are paramount to alleviate pervasive food and nutrition security and food safety issues and achieve a world free from hunger and malnutrition. Modern breeding techniques have been the key to transforming crop production systems and developing stress- and climate-resilient crops. As a rapidly evolving technology, the Nobel Prize-winning CRISPR method is a leading choice for genome editing and a possible major contributor to solving environmental and food insecurity issues. Here, a background on the stressors with far-reaching impacts on food security has been provided, and the principles and advances in classical genome editing (CRISPR/Cas9) that generate DNA double-strand breaks (DSB) have been reviewed. Base editing and prime editing platforms, which are DSB- and template-free, enabling targeted base substitutions, have been discussed. The application of such tools for trait improvement has been evaluated to develop stressresilient crops and high-throughput mutant libraries. Recent developments in the regulatory landscape for genome-edited crops in various countries have been examined. Finally, the challenges and future perspectives toward crop improvement have been highlighted.

Background: The versatile 2-alkynylbenzamde has been reported to produce many privileged skeletons, like isoquinolin-1-ones, isocoumarin-1-imines, isoindolin-1-ones, and isobenzofuran- 1-imines. Recently, we reported the projected transformation using copper salt (CuCl2) as a catalyst under the O2 atmosphere. To expand the scope of the reaction, we used another inexpensive metal salt, MnO2, as a catalyst. Methods: The paper aims to explore a manganese-catalyzed reaction of 2-alkynylbenzamide under an O2 balloon for the synthesis of 3-hydroxylisoquinolin-1,4-dione. Results: Results on reaction scope shows the 10 mol% MnO2 in O2 atmosphere and DCE solvent catalyzed the cyclization of 2-alkynylbenzamide to produce 3-hydroxylisoquinolin-1,4-diones in 40-68% isolated yields. The reaction proceeds through a regioselective N-center radical 6-endo-dig aza-cyclization pathway. Conclusion: We have developed a manganese-catalyzed cyclization of 2-alkynlbenzamide for the synthesis of 3-hydroxylisoquinolin-1,4-diones under an O2 balloon. It is believed that the N-center radical-based 6-endo dig aza-cyclization proceeded in a regioselective manner.