Design and synthesis of oridonin derivatives as cytotoxic agents.

Oridonin is one of the -kaurane diterpenes that have been studied extensively for various bioactivities. In an effort to expand natural scaffold-based library as anticancer agents, we have designed and synthesised a number of novel oridonin derivatives and evaluated their bioactivities on a panel of human cancer cell lines (HCT116, A375, MCF-7, HepG2, and A549). Compound bearing a 4-fluorophenyl moiety was found to be the most active compound with an IC value of 0.

Optimized Dropkey-Based Grad-CAM: Toward Accurate Image Feature Localization.

Regarding the interpretable techniques in the field of image recognition, Grad-CAM is widely used for feature localization in images to reflect the logical decision-making information behind the neural network due to its high applicability. However, extensive experimentation on a customized dataset revealed that the deep convolutional neural network (CNN) model based on Gradient-weighted Class Activation Mapping (Grad-CAM) technology cannot effectively resist the interference of large-scale noise. In this article, an optimization of the deep CNN model was proposed by incorporating the Dropkey and Dropout (as a comparison) algorithm.

Identification and bioactivity evaluation of miliusanes from Miliusa sinensis.

Miliusanes are a class of anticancer lead molecules belonging to meroterpenoids with an 18-carbon skeleton isolated from Miliusa plants. A phytochemical study of the plant M. sinensis was carried out to discover new miliusanes with diverse structural features in order to better understand their structure-activity relationship.

Isolation and Anticancer Progression Evaluation of the Chemical Constituents from Tutcher.

The dichloromethane extract of the roots of Tutcher (Phyllanthaceae) was found to show potential anticancer activity against HCT116 colorectal cancer cell. Our bioassay-guided phytochemical investigation of the roots of led to the identification of 14 compounds including seven lignans (-), three phenylbenzene derivatives (-), two flavanone (-), and two triterpenoids (-). Among them, 4'-demethyl-4-deoxypodophyllotoxin () is the first aryltetralin lignan compound identified from this plant species.

Dihydro-Resveratrol Attenuates Oxidative Stress, Adipogenesis and Insulin Resistance in In Vitro Models and High-Fat Diet-Induced Mouse Model via AMPK Activation.

Management of obesity has become a prevalent strategy for preventing the diseases closely integrated with excess body weight such as diabetes over the last half century. Searching for therapeutic agents acting on oxidative stress, adipogenesis and insulin resistance is considered as an efficient approach to control obesity-related diseases. The present study was designed to examine the in vitro and in vivo effects of dihydro-resveratrol (DR2), a naturally occurring compound from medicinal plants, on oxidative stress aggravation, adipogenesis, lipogenesis and insulin sensitivity.

Temperature-Dependent Photoluminescence of CdS/ZnS Core/Shell Quantum Dots for Temperature Sensors.

Exploring the temperature-dependent photoluminescence (PL) properties of quantum dots (QDs) is not only important for understanding the carrier recombination processes in QD-based devices but also critical for expanding their special applications at different temperatures. However, there is still no clear understanding of the optical properties of CdS/ZnS core/shell QDs as a function of temperature. Herein, the temperature-dependent PL spectra of CdS/ZnS core/shell QDs were studied in the temperature range of 77-297 K.

Room temperature preparation of cellulose nanocrystals with high yield via a new ZnCl solvent system.

Here, a facile method to fabricate cellulose nanocrystals (CNCs) with high yield from microcrystalline cellulose (MCC) at room temperature (RT) is achieved by using a new solvent system of zinc chloride (ZnCl) and a little amount of hydrochloric acid (HCl). Compared with sulphuric acid hydrolysis process, about one-fifth mole of acid is used for per gram of CNCs in our protocol. CNCs with rod-like morphology are regenerated with a maximum yield of 35.

N and P co-doped MXenes nanoribbons for electrodeposition-free stripping analysis of Cu(II) and Hg(II).

The present electrochemical stripping analysis (ESA) for multiple heavy metal ions (HMI) generally requires an electrodeposition process at a very low potential below -1.0 V, which inevitably makes the sensing procedures more complex, inefficient and power-wasting. Meanwhile, the emerging MXenes rising-star materials have been studied in various fields recently.

Support-Seeking Strategies and Social Support Provided in Chinese Online Health Communities Related to COVID-19.

Online health communities have become one of the most important means for people to seek social support during the coronavirus 2019 disease (COVID-19) pandemic. This study details content analysis of support-seeking strategies and social support offered on the online forum "Baidu COVID-19bar" across different stages of initial stage as well as during the entire initial stage of the COVID-19 pandemic. The results show that asking for support and disclosing directly were the main strategies used across the different stages and during the entire initial stage.

Free-electrodeposited anodic stripping voltammetry sensing of Cu(II) based on TiCT MXene/carbon black.

A proof-of-principle concept for free-electrodeposited anodic stripping voltammetry (ASV) sensing of Cu is proposed by using TiCT MXene/carbon black (TiCT@CB) nanohybrids as electrode materials. Owing to the high adsorption and reduction capability of TiCT towards Cu, TiCT MXene enables Cu to be immobilized and self-reduced directly to form Cu on the TiCT@CB electrode surface. As a result an oxidation peak current appears from the re-oxidation of Cu via differential pulse voltammetry.

Novel methodology for anodic stripping voltammetric sensing of heavy-metal ions using TiCT nanoribbons.

Conventional anodic stripping voltammetry (ASV) sensing of heavy-metal ions (HMIs) generally includes a two-step approach: (a) preconcentration via electrodeposition and (b) re-oxidation, while the requirement of the electrodeposition step makes the detection processes more complex. Herein, a novel methodology using self-reduction instead of electrodeposition was developed for the ASV sensing of HMIs (selecting Cd2+ as a representative analyte) by introducing Ti3C2Tx MXene nanoribbons (Ti3C2Tx NR) as a sensing element that can exhibit direct adsorption and reduction capabilities towards HMIs. Compared with conventional ASV technology, the proposed methodology is simpler and power-saving, and has a significant low detection limit (0.

Natural Cyclopeptides as Anticancer Agents in the Last 20 Years.

Cyclopeptides or cyclic peptides are polypeptides formed by ring closing of terminal amino acids. A large number of natural cyclopeptides have been reported to be highly effective against different cancer cells, some of which are renowned for their clinical uses. Compared to linear peptides, cyclopeptides have absolute advantages of structural rigidity, biochemical stability, binding affinity as well as membrane permeability, which contribute greatly to their anticancer potency.

Mechanistic Pathways and Molecular Targets of Plant-Derived Anticancer -Kaurane Diterpenes.

Since the first discovery in 1961, more than 1300 -kaurane diterpenoids have been isolated and identified from different plant sources, mainly the genus . Chemically, they consist of a perhydrophenanthrene subunit and a cyclopentane ring. A large number of reports describe the anticancer potential and mechanism of action of -kaurane compounds in a series of cancer cell lines.

Flexicaulin A, An -Kaurane Diterpenoid, Activates p21 and Inhibits the Proliferation of Colorectal Carcinoma Cells through a Non-Apoptotic Mechanism.

Natural products, explicitly medicinal plants, are an important source of inspiration of antitumor drugs, because they contain astounding amounts of small molecules that possess diversifying chemical entities. For instance, (formerly ), a genus of the Lamiaceae (formerly Labiatae) family, has been reported as a rich source of natural diterpenes. In the current study, we evaluated the in vitro anti-proliferative property of flexicaulin A (FA), an diterpenoid with an -kaurane structure, in human carcinoma cells, by means of cell viability assay, flow cytometric assessment, quantitative polymerase chain reaction array, Western blotting analysis, and staining experiments.

In Vitro and in Vivo Antitumor Effects of Plant-Derived Miliusanes and Their Induction of Cellular Senescence.

Our earliest phytochemical separation of Miliusa sinensis aided us in the isolation of a class of unique miliusanes, which were demonstrated as anticancer lead molecules. In the present study, we isolated 19 miliusanes (1-19), including 11 novel ones (5 and 10-19) from another Miliusa plant ( M. balansae), and synthesized additional derivatives to elucidate the structure-activity relationship of miliusanes.

Resveratrol Ameliorates the Severity of Fibrogenesis in Mice with Experimental Chronic Pancreatitis.

Scope: Resveratrol is generally considered beneficial to health-span and longevity since this dietary stilbenoid has been scrutinized for its activating property on the "rescue gene" sirtuin-1 that promotes cellular survival under stress. In addition to its antiaging property, our previous in vitro studies revealed that resveratrol notably inhibits the production of extracellular matrix (ECM) proteins in pancreatic stellate cells (PSCs), the classic effector cells against pancreatic injury.

Objective: We aim to extrapolate resveratrol intervention to the management of fibrogenesis in mice with chronic pancreatitis.