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761.
Katar na G borov Marcela Achimovi&ccaron ov Michal Heged s Vladim r Girman M ria Ka&ncaron uchov Erika Dutkov 《Frontiers of Chemical Science and Engineering》2022,16(3):433
Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ~25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2– oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se. 相似文献
762.
Ingrid Rivera-Íñiguez Karina González-Becerra Omar Ramos-Lopez Yolanda E. Peréz-Beltrán Marian S. Chagüén-Hernández Erika Martínez-López Edgar J. Mendivil 《Molecular nutrition & food research》2023,67(14):2200675
Dyslipidemias are known risk factors for chronic diseases. Precision nutrition interventions are designed according to characteristics, such as diet, phenotype, and genotype. This systematic review aims to define a panel of genetic variants associated with lipid abnormalities that could be later used in nutrigenetic intervention studies. A systematic review is conducted following the PRISMA-P. Studies published from January 2010 to December 2020 in English language and humans are included from PubMed and ScienceDirect databases. Articles that demonstrate a strong association between polymorphisms (single nucleotide variation) of genes involved in lipid metabolism and increased risk for dyslipidemia are included. A total of 3031 articles are screened, but only 51 articles fulfill the inclusion criteria. The genes included are FABP2, MTTP related to CM synthesis and secretion; LPL, LIPC involved in triglyceride hydrolysis; CETP, APOA1, LCAT, ABCA1, and APOA5 related to lipoprotein metabolism, and APOE, LDLR, SCARB1, APOC3 involved in lipid clearance. In this systematic review, genetic variants related to chylomicron synthesis, triglyceride hydrolysis, lipoprotein metabolism, and lipid clearance demonstrate a strong association with lipid abnormalities, which can be used to design precision nutrition interventions that may help to prevent and treat dyslipidemia effectively. 相似文献
763.
Antonella Rosa Mariella Nieddu Federica Pollastro Cristina Piras 《European Journal of Lipid Science and Technology》2023,125(3):2200128
The fatty acid (FA) composition of cell membranes represents a metabolic biomarker. However, the FA profile reproducibility in cell cultures remains a significant challenge. In this study, cell FA ratios are validated as metabolic markers alternative to cell FA. To this goal, cell samples belonging to cancer HeLa cells and normal 3T3 fibroblasts, from various experimental sets, are analyzed by a high-performance liquid chromatography system coupled with a photodiode array detector and evaporative light scattering detector (HPLC-DAD/ELSD), and the ratios among the main FA are calculated. Principal component analysis (PCA) separately performed on FA and FA ratio data indicates similar clustering of cell samples concerning the cell type. Moreover, similar scores values t[1] and t[2] and graphical distances are calculated in the PCA plots separately performed on FA and FA ratios measured in cancer HeLa cells subjected to various antitumoral compounds. Last, PCA applied to selected FA ratios measured in various cell lines, obtained in similar experimental conditions, allows to discriminate between normal and tumoral cells. The results substantiate FA ratios as a cell-specific fingerprint, characterized by reproducibility across intra-laboratory conditions, useful for cell characterization, discrimination between normal and tumoral cells, and the comparison of different drug treatments. Practical Applications: The reproducibility of the fatty acid (FA) profile in cell cultures remains a significant challenge. Results obtained from this study improve knowledge about the role of the FA ratio profile as a cell-specific fingerprint characterized by reproducibility across intra-laboratory conditions. The characterization of the specific FA ratio profile of a cell culture, under standardized experimental conditions, can facilitate the comparative evaluation of cell data sets for nutritional, metabolic, and pharmacological studies, overcoming differences in cell culture conditions and FA extraction/analytical procedures. 相似文献
764.
Dr. Yuma Shisaka Dr. Erika Sakakibara Dr. Kazuto Suzuki Dr. Joshua Kyle Stanfield Dr. Hiroki Onoda Garyo Ueda Miu Hatano Dr. Hiroshi Sugimoto Prof. Osami Shoji 《Chembiochem : a European journal of chemical biology》2022,23(14):e202200095
Tetraphenylporphyrin (TPP) is a symmetrically substituted synthetic porphyrin whose properties can be readily modified, providing it with significant advantages over naturally occurring porphyrins. Herein, we report the first example of a stable complex between a native biomolecule, the haemoprotein HasA, and TPP as well as its derivatives. The X-ray crystal structures of nine different HasA-TPP complexes were solved at high resolutions. HasA capturing TPP derivatives was also demonstrated to inhibit growth of the opportunistic pathogen Pseudomonas aeruginosa. Mutant variants of HasA binding FeTPP were shown to possess a different mode of coordination, permitting the cyclopropanation of styrene. 相似文献