IR spectra of paracetamol

Paracetamol is a very popular medication used to treat pain and fever. IR spectra of paracetamol have been measured for powder crystals. Ab initio calculations of its equilibrium geometry and vibrational spectra were carried out for spectrum interpretation. Differences between the experimental IR spectra of crystalline samples have been analyzed. Variations of molecular structure from the isolated state to molecular crystal were estimated based on the difference between the optimized molecular parameters of free molecules and the experimental bond lengths and angles evaluated for the crystal forms of the title compounds. The role of hydrogen bonds in the structure of molecular crystals of paracetamol is investigated. Bangladesh J. Sci. Ind. Res.56(4), 255-262, 2021

Thymol and Piperine-Loaded Poly(D,L-lactic-co-glycolic acid) Nanoparticles Modulate Inflammatory Mediators and Apoptosis in Murine Macrophages

This study aimed at preparing and characterizing thymol, eugenol, and piperine-loaded poly(D,L-lactic-co-glycolic acid) nanoparticles and evaluating the effect on inflammatory mediators secretion and apoptosis in Raw 264.7 macrophage cells. Nanoparticles were produced by the solvent evaporation technique. Dynamic light scattering and scanning electron microscopy were used to study the physicochemical characteristics. Raw 264.7 macrophage cells were used as a model for in vitro assays. The 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium assay was used to determine the cytotoxicity of the formulated nanoparticles. An annexin V apoptosis detection kit was used to assess apoptosis. Nitric oxide production was determined using the Griess reagent, and the inflammatory mediators level was evaluated with Th1/Th2 cytokine and fluorometric cyclooxygenase kits. The loaded nanoparticles showed a particle size around 190 nm with a low polydispersity between 0.069 and 0.104 and a zeta potential between–1.2 and–9.5 mV. Reduced cytotoxicity of nanoparticles compared to free molecules against Raw 264.7 macrophage cells was observed and seemed to occur through a mechanism associated with apoptosis. A decrease in cyclooxygenase enzyme activity with an increasing concentration was observed. Both free molecules and nanoparticles showed their capacity to modulate the inflammatory process mostly by inhibiting the investigated inflammatory cytokines. The data presented in this study indicate that thymol and piperine-loaded poly(D,L-lactic-co-glycolic acid nanoparticles could serve as a novel anti-inflammatory colloidal drug delivery system with reduced toxicity. However, further study should be considered to optimize the formulation’s loading capacity and thereby probably enhance their bioactivity in treating inflammatory diseases.

Nociception and Pain: New Roles for Exosomes

The interchange of information from one cell to another relies on the release of hundreds of different molecules including small peptides, amino acids, nucleotides, RNA, steroids, retinoids, or fatty acid metabolites. Many of them are released to the extracellular matrix as free molecules and others can be part of the cargo of cellular vesicles. Small extracellular vesicles (30–150 nm), also known as exosomes, are a known mechanism of cell-to-cell communication in the nervous system. Exosomes participate in the pathogenesis of several neurological conditions including Alzheimer’s and Parkinson’s disease. However, exciting emerging evidence demonstrates that exosomes also regulate mechanisms of the sensory process including nociception. The goal of this review is to summarize the literature on exosome biogenesis, methods of small vesicle isolation and purification, and their role in nociception. We also provide insights on the potential applications of exosomes as pain biomarkers or as novel therapeutics.

A Bittersweet Computational Journey among Glycosaminoglycans

Glycosaminoglycans (GAGs) are linear polysaccharides. In proteoglycans (PGs), they are attached to a core protein. GAGs and PGs can be found as free molecules, associated with the extracellular matrix or expressed on the cell membrane. They play a role in the regulation of a wide array of physiological and pathological processes by binding to different proteins, thus modulating their structure and function, and their concentration and availability in the microenvironment. Unfortunately, the enormous structural diversity of GAGs/PGs has hampered the development of dedicated analytical technologies and experimental models. Similarly, computational approaches (in particular, molecular modeling, docking and dynamics simulations) have not been fully exploited in glycobiology, despite their potential to demystify the complexity of GAGs/PGs at a structural and functional level. Here, we review the state-of-the art of computational approaches to studying GAGs/PGs with the aim of pointing out the “bitter” and “sweet” aspects of this field of research. Furthermore, we attempt to bridge the gap between bioinformatics and glycobiology, which have so far been kept apart by conceptual and technical differences. For this purpose, we provide computational scientists and glycobiologists with the fundamentals of these two fields of research, with the aim of creating opportunities for their combined exploitation, and thereby contributing to a substantial improvement in scientific knowledge.

Квантово-химическое моделирование эндофуллеренов металлов подгруппы скандия

Эндофуллерены, содержащие один или несколько атомов металла внутри углеродного каркаса (металлофуллерены), представляют большой практический интерес в связи с возможностью создания на их основе эффективных контрастирующих агентов для магнитно-резонансной томографии (МРТ), антиоксидантных и противораковых средств. Данные соединения могут быть также использованы в спинтронике для создания наноразмерных электронных устройств. В настоящей работе в рамках теории функционала плотности произведен расчет структурных, электронных и термодинамических характеристик эндофуллеренов металлов подгруппы скандия с числом инкапсулированных атомов от одного до семи в газовой фазе. Описаны стабильные структуры с симметриямиCs, C2, C3 и Ci, соответствующие позициям, занимаемым атомами металла внутри каркаса фуллерена. Установлен теоретический предел числа атомов металла, при котором структура эндофуллерена сохраняет устойчивость – шесть атомов для скандия, четыре для иттрия и три для лантана. 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