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81.
Convolvulus arvensis is used in Pakistani traditional medicine to treat inflammation-related disorders. Its anti-inflammatory potential was evaluated on hexane, dichloromethane, ethyl acetate, methanol, and aqueous extracts of whole plant on pro-inflammatory mediators in LPS-activated murine macrophage J774 cells at the non-cytotoxic concentration of 50 µg/mL. Ethyl acetate (ARE) and methanol (ARM) extracts significantly decreased mRNA levels of IL-6, TNF-α, MCP-1, COX-2, and iNOS. Furthermore, both extracts dose dependently decreased IL-6, TNF-α, and MCP-1 secretion. Forty-five compounds were putatively identified in ARE and ARM by dereplication (using HPLC-UV-HRMSn analysis and molecular networking), most of them are reported for the first time in C. arvensis, as for example, nineteen phenolic derivatives. Rutin, kaempferol-3-O-rutinoside, chlorogenic acid, 3,5-di-O-caffeoylquinic acid, N-trans-p-coumaroyl-tyramine, and N-trans-feruloyl-tyramine were main constituents identified and quantified by HPLC-PDA in ARE and ARM. Furthermore, chlorogenic acid, tyramine derivatives, and the mixture of the six identified major compounds significantly decreased IL-6 secretion by LPS-activated J774 cells. The activity of N-trans-p-coumaroyl-tyramine is shown here for the first time. Our results indicate that ARE, ARM and major constituents significantly inhibited the expression of pro-inflammatory mediators, which supports the use of this plant to treat inflammatory diseases.  相似文献   
82.
Diabetes mellitus is a chronic metabolic disorder in which the pancreas secretes insulin but the body cells do not recognize it. As a result, carbohydrate metabolism causes hyperglycemia, which may be fatal for various organs. This disease is increasing day by day and it is prevalent among people of all ages, including young adults and children. Acarbose and miglitol are famous alpha-glucosidase inhibitors but they complicate patients with the problems of flatulence, pain, bloating, diarrhea, and loss of appetite. To overcome these challenges, it is crucial to discover new anti-diabetic drugs with minimal side effects. For this purpose, benzotriazinone sulfonamides were synthesized and their structures were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopy. In vitro alpha-glucosidase inhibition studies of all synthesized hybrids were conducted using the spectrophotometric method. The synthesized compounds revealed moderate-to-good inhibition activity; in particular, nitro derivatives 12e and 12f were found to be the most effective inhibitors against this enzyme, with IC50 values of 32.37 ± 0.15 µM and 37.75 ± 0.11 µM. In silico studies, including molecular docking as well as DFT analysis, also strengthened the experimental findings. Both leading compounds 12e and 12f showed strong hydrogen bonding interactions within the enzyme cavity. DFT studies also reinforced the strong binding interactions of these derivatives with biological molecules due to their lowest chemical hardness values and lowest orbital energy gap values.  相似文献   
83.
The photolyase family consists of flavoproteins with enzyme activity able to repair ultraviolet light radiation damage by photoreactivation. DNA damage by the formation of a cyclobutane pyrimidine dimer (CPD) and a pyrimidine-pyrimidone (6-4) photoproduct can lead to multiple affections such as cellular apoptosis and mutagenesis that can evolve into skin cancer. The development of integrated applications to prevent the negative effects of prolonged sunlight exposure, usually during outdoor activities, is imperative. This study presents the functions, characteristics, and types of photolyases, their therapeutic and cosmetic applications, and additionally explores some photolyase-producing microorganisms and drug delivery systems.  相似文献   
84.
The nonheme iron dioxygenase 2-(trimethylammonio)-ethylphosphonate dioxygenase (TmpA) is an enzyme involved in the regio- and chemoselective hydroxylation at the C1-position of the substrate as part of the biosynthesis of glycine betaine in bacteria and carnitine in humans. To understand how the enzyme avoids breaking the weak C2−H bond in favor of C1-hydroxylation, we set up a cluster model of 242 atoms representing the first and second coordination sphere of the metal center and substrate binding pocket, and investigated possible reaction mechanisms of substrate activation by an iron(IV)-oxo species by density functional theory methods. In agreement with experimental product distributions, the calculations predict a favorable C1-hydroxylation pathway. The calculations show that the selectivity is guided through electrostatic perturbations inside the protein from charged residues, external electric fields and electric dipole moments. In particular, charged residues influence and perturb the homolytic bond strength of the C1−H and C2−H bonds of the substrate, and strongly strengthens the C2−H bond in the substrate-bound orientation.  相似文献   
85.
Journal of Thermal Analysis and Calorimetry - The objective of this paper is to develop the influences of channel waviness on the performance of a latent heat storage system during phase change...  相似文献   
86.
Abstract

The solid-state structures of compounds PPh2CH2SPh (1) and PPh2C6H4SMe (2) were determined by single crystal X-ray diffraction. Experimental results on the molecular structures of compounds 1 and 2 were supported by Hirshfeld surface analysis and Density Functional Theory (DFT). The computed values calculated at DFT level using B3LYP function with 6-311++G (3df, 3pd) (P, S) and 6-31G* (C, H) basis sets are in good agreement with the experimental results.  相似文献   
87.
Journal of Thermal Analysis and Calorimetry - This article investigates the performance of a novel hybrid heat pump system, which is developed to recover the waste heat from the flue gas of...  相似文献   
88.
Optical and Quantum Electronics - In this paper, the simultaneous impact of interference and aggregated hardware impairments on the performance of mixed radio frequency/free space optical (RF/FSO)...  相似文献   
89.
In addition to the conversion from p-type to n-type conductivity that occurs in Ge–Se–Bi thin films when Bi is incorporated in a certain concentration. We found that, when these films were illuminated to UV light, after being annealed at glass transition temperature T g, the photobleaching is dominant for Ge20Se80?x Bi x (x=0, 2.5, and 5 at.%), while for Ge20Se72.5Bi7.5 photodarkening is dominant. The photoinduced changes in the optical constants were studied. The refractive index (n) has been analysed according to the Wwmple–DiDominico single oscillator model and the values of E o and E d for exposed and unexposed films were determined, respectively. The photostructural effects were discussed in the light of single–double well model proposed by Tanaka and chemical bond approach.  相似文献   
90.
A series of new pyrazolone and pyrazole derivatives with expected antifungicidal activity have been prepared through the reactions 3‐phenyl‐1‐H‐pyrazol‐5(4H)‐one ( 3 ) and 4‐(dimethylaminomethylene)‐3‐phenyl‐1H‐pyrazol‐5(4H)‐one ( 5 ) with a variety of electrophilic reagents and nucleophilic reagents. The newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR and mass spectral studies.  相似文献   
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