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Flos Carthami (FC) has a good therapeutic effect on chronic alcoholic liver injury (CALI) in clinical practice, but the treatment mechanism is not very clear. Therefore, elucidating the molecular mechanism of action of FC in treating CALI is of great significance for the further development and application of drugs. Male Wistar rats were as the research object. The model group rats were orally administered with 8 mL/kg alcohol for 28 days to establish a CALI model, while the treatment group rats were orally administered with high (4.2903 g/kg), medium (1.4301 g/kg), and low (0.4767 g/kg) doses of FC extract. Potential biomarkers related to CALI were identified using rat serum metabonomics analysis methods combined with ultra-high performance liquid chromatography mass spectrometry (UHPLC-MS) technology, and the regulatory mechanisms of FC on these biomarkers were investigated. The BP neural network model was established by MATLAB software to deal with the classification problem of omics data. The H&E staining experiment found that after gavage, high-dose FC extract can reduce the degree of liver cell damage. Compared with the model group, the expression levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the high-dose FC group decrease, indicating that the high-dose FC extract has liver protective effect. The classification accuracy of the BP neural network model is 95.8%, and the classification effect is good. Through volcanic map analysis, a total of twenty biomarkers related to CALI are identified, and FC can have a callback effect on these biomarkers. The results indicated that FC may exert therapeutic effect on CALI by regulating the metabolism of triglycerides, fatty acids, phospholipids, bile acids, amino acids and Vitamin E. This study provides a theoretical foundation for the promotion and clinical application.

Abstract Background Although stem cell transplantation is a promising approach for the treatment of myocardial infarction (MI), there are still some problems faced such as the low survival rate of stem cells. Here, we investigated the role of Notoginsenoside R1 (NGR1) pretreatment in improving the effects of neonatal rat bone marrow mesenchymal stem cell (MSC) transplantation for treatment of MI. Methods Cardiac functions were detected by echocardiography and the myocardial infarct size was determined by Masson’s trichrome staining in a rat model of MI. The cardioprotective effects of NGR1/LY294002 co-pretreated MSCs was evaluated to explore the underlying mechanism. The angiogenesis was determined by vWF and α-SMA immunofluorescence staining and cell apoptosis was detected by TUNEL. In vitro, the effects of NGR1 on stem cell proliferation was examined by CCK-8 and levels of P-Akt, P-CREB, P-FoxO1 were detected by western blot. Apoptosis, ROS content, and cytokine levels were examined by DAPI and TUNEL staining, a ROS assay kit, and ELISA, respectively. Results NGR1 elevated the therapeutic effect of MSC transplantation on infarction by preserving cardiac function, increasing angiogenesis and expressions of IGF-1, VEGF, and SDF-1, and reducing cell apoptosis, whereas the addition of LY294002 prior to NGR1 treatment significantly counteracted the foregoing effects of NGR1. NGR1 pretreatment and SC79 pretreatment were similar in that both significantly increased P-Akt and P-FoxO1 levels in MSC and did not affect P-CREB levels. Besides, both NGR1 and SC79 promoted VEGF, SCF and bFGF levels in MSC cultures, and significantly reduced ROS accumulation and the attenuated cell apoptosis in MSC triggered by H2O2. Similarly, addition of LY294002 before NGR1 treatment significantly counteracted the aforementioned effects of NGR1 in vitro. Conclusions NGR1 pretreatment enhances the effect of MSC transplantation for treatment of MI through paracrine signaling, and the mechanism underlying this effect may be associated with PI3K/Akt/FoxO1 signaling pathways.

Since 1982, Landsat series of satellite sensors continuously acquired thermal infrared images of the Earth’s land surface. In this study, Landsat 5, 7, and 8 land surface temperature (LST) products in the conterminous United States from 2009 to 2019 were validated using in situ measurements collected at 6 SURFRAD (Surface Radiation Budget Network) sites, 6 ARM (Atmospheric Radiation Measurement) sites, and 9 NDBC (National Data Buoy Center) sites. The results indicate that a relatively consistent performance among Landsat 5, 7, and 8 LST products is obtained for most sites due to the consistent LST retrieval algorithm in conjunction with the same atmospheric compensation and land surface emissivity (LSE) correction methods for Landsat 5, 7, and 8 sensors. Large bias and root mean square error (RMSE) of Landsat LST product are obtained at some vegetated sites due to incorrect LSE estimation where LSE is invariant with the increasing of normalized difference vegetation index (NDVI). Except for the sites with incorrect LSE estimation, a mean bias (RMSE) of the differences between Landsat LST and in situ LST is 1.0 K (2.1 K) over snow-free land surfaces, −1.1 K (1.6 K) over snow surfaces, and −0.3 K (1.1 K) over water surfaces.

Land surface temperature (LST) is an important variable in the physics of land–surface processes controlling the heat and water fluxes over the interface between the Earth’s surface and the atmosphere. Space-borne remote sensing provides the only feasible way for acquiring high-precision LST at temporal and spatial domain over the entire globe. Passive microwave (PMW) satellite observations have the capability to penetrate through clouds and can provide data under both clear and cloud conditions. Nonetheless, compared with thermal infrared data, PMW data suffer from lower spatial resolution and LST retrieval accuracy. Various methods for estimating LST from PMW satellite observations were proposed in the past few decades. This paper provides an extensive overview of these methods. We first present the theoretical basis for retrieving LST from PMW observations and then review the existing LST retrieval methods. These methods are mainly categorized into four types, i.e., empirical methods, semi-empirical methods, physically-based methods, and neural network methods. Advantages, limitations, and assumptions associated with each method are discussed. Prospects for future development to improve the performance of LST retrieval methods from PMW satellite observations are also recommended.

Organoboron compounds are widely used in catalytic reactions, medicinal chemistry, chemosensors, and polymer applications, because of their low toxicity, high stability, Lewis acidity, chemical versatility, and ability to form covalent bonds with their nucleophilic targets, In this report, we demonstrate how to efficiently assemble tetra boronate‐containing compounds at the gram‐scale via a one‐pot modified microwave‐assisted Ugi‐4CR reaction. These boronate esters can then be transformed into the corresponding boronic acids under a reliable deprotection method, also reported herein. [ABSTRACT FROM AUTHOR]

In this report, 19 boron-containing depsipeptides were synthesized via microwave-assisted Passerini three-component reaction (P-3CR) in an aqueous environment. The linker-free DAHMI fluorescent tagging approach was used on selected boron-containing compounds to study the relationship between their structures and their level of cellular uptake of HEK293 cells. The biological data retrieved from the DAHMI experiments indicated that while the structures of tested compounds may be highly similar, their bio-distribution profile could be vastly distinctive. The reported optimized one-pot synthetic strategy along the linker-free in vitro testing protocol could provide an efficient platform to accelerate the development of boron-containing drugs. [ABSTRACT FROM AUTHOR]

Based on the fact that the kinetic energy of one atom in small cluster still obeys the Boltzmann distribution, a statistical model is developed to predict the time consumed by a small cluster transforming from one isomer to another and is tested by vast molecular dynamics simulations of C12 isomers transformation in helium gas at high temperatures (2000–3500 K). Extrapolating the model to lower temperatures, we found that the time for the most probable isomer of C12 formed at 2500 K turning into the most stable one is more than 1012 years at room temperature. [ABSTRACT FROM AUTHOR]

Land surface temperature (LST) plays an important role in land surface processes, and it is a key input for estimating important hydrological states and fluxes, such as soil moisture and evapotranspiration. In this study, a three-channel method is proposed to retrieve cloudy LST values from passive microwave data based on the relationship among surface emissivities at 18.70, 36.50, and 89.00 GHz over a bare soil surface. The performance of the method was evaluated using simulated data, resulting in a root mean square error (RMSE) of approximately 1.4 K over the bare soil surface. This method was further extended to retrieve cloudy LST values over a natural surface. Due to the lack of in situ LST measurements, ground-based air temperatures were used as proxy data to validate the cloudy LST values retrieved from AMSR-E data. The RMSE values of the differences between the retrieved cloudy LST values and the ground-based air temperatures are approximately 3.4 K and 4.3 K for the descending and ascending overpasses, respectively. The results demonstrate that the three-channel method can be used to retrieve cloudy LST values from passive microwave data with reasonable accuracy. [ABSTRACT FROM AUTHOR]

Satellite remote sensing provides a unique way to measure land surface temperature (LST) at regional and global scales. Algorithms using thermal infrared (TIR) data provide a reliable way to retrieve LST. However, they are limited to clear-sky conditions due to their inability to penetrate clouds. As an alternative for LST retrieval, passive microwave data are much less affected by clouds and water vapour than TIR data. In this study, we presented an improved physically based algorithm for the retrieval of LST under cloudy atmospheric conditions from Advanced Microwave Scanning Radiometer 2 (AMSR2) brightness temperature measurements at 18.7 and 23.8 GHz vertically polarized channels based on the assumption that the emissivity relationship between the two adjacent frequencies is linear. The performance of the algorithm was firstly evaluated using simulation data, with a root mean square error (RMSE) of approximately 2.1 K. Moreover, the RMSE value reduces with precipitable water vapour (PWV) increasing. This algorithm was further applied to AMSR2 measurements. The retrieved cloudy LST was compared with ground-based air temperature over China in 2016. The bias varies from approximately 2 K to 4 K and the RMSE from approximately 4 K to 6 K during daytime and night-time. To eliminate the systematic bias between the retrieved LST and the ground-based air temperature, a linear adjustment was performed to the retrieved LST during daytime and nighttime, respectively. The accuracies for the adjusted LST are nearly the same during daytime and night-time, with an RMSE of approximately 3.6 K. The combination of this physically based LST retrieval algorithm with TIR LST algorithm is attractive for generating an all-weather LST product at global scale. [ABSTRACT FROM AUTHOR]

Keywords: Boronic acid; Deprotection; Microwave chemistry; Multicomponent reactions; Ugi-4CR EN Boronic acid Deprotection Microwave chemistry Multicomponent reactions Ugi-4CR 1 1 1 08/23/22 20220819 NES 220819 B The Front Cover b illustrates how easy the gram-scale synthesis of tetraboronates by using a microwave machine is. Boronic acid, Deprotection, Microwave chemistry, Multicomponent reactions, Ugi-4CR Front Cover: Robust Synthesis of Tetra-Boronate Esters Analogues and the Corresponding Boronic Acids Derivatives (Eur. J. Org. [Extracted from the article]

The authors would like to correct an error in the title paper [...]