Search results for "Organic chemistry"
showing 10 items of 17180 documents
Interaction Between Cytokines and Oxidative Stress in Acute Pancreatitis
2006
Acute pancreatitis is an inflammation initially localized in the pancreatic gland which may lead to local and systemic complications. The development of severe acute pancreatitis is mediated by pathophysiological mechanisms involved in the systemic inflammatory response, cytokines and oxidative stress being their components of major importance. Nevertheless, it is still unknown why an episode of acute pancreatitis remains mild or progresses to a severe form. Activated leukocytes are the main source of cytokines. Interleukin 1beta and tumor necrosis factor alpha (TNF-alpha) initiate and propagate almost all the consequences of the systemic inflammatory response syndrome, leading to amplifica…
2021
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for the COVID-19 pandemic, which generated more than 1.82 million deaths in 2020 alone, in addition to 83.8 million infections. Currently, there is no antiviral medication to treat COVID-19. In the search for drug leads, marine-derived metabolites are reported here as prospective SARS-CoV-2 inhibitors. Two hundred and twenty-seven terpene natural products isolated from the biodiverse Red-Sea ecosystem were screened for inhibitor activity against the SARS-CoV-2 main protease (Mpro) using molecular docking and molecular dynamics (MD) simulations combined with molecular mechanics/generalized Born surface area b…
Characterization of the synthetic cannabinoid MDMB-CHMCZCA
2016
The synthetic cannabinoid MDMB-CHMCZCA was characterized by various spectroscopic techniques including NMR spectroscopy and tandem mass spectrometry. The synthetic sample was found to be of S-configuration by VCD spectroscopy and comparison of the data with DFT calculations, while ECD spectroscopy was found to be inconclusive in this case. The enantiomeric purity of samples from test purchases and police seizures was assessed by a self-developed chiral HPLC method.
Encapsulation of Vitamins A and E as Spray-Dried Additives for the Feed Industry
2020
Encapsulated fat-soluble powders containing vitamin A (VA) and E (VE) were prepared as a feasible additive for extruded feed products. The effect of the encapsulating agents (Capsul-CAP®
Cannabidiol Treatment Might Promote Resilience to Cocaine and Methamphetamine Use Disorders: A Review of Possible Mechanisms
2019
Currently, there are no approved pharmacotherapies for addiction to cocaine and other psychostimulant drugs. Several studies have proposed that cannabidiol (CBD) could be a promising treatment for substance use disorders. In the present work, the authors describe the scarce preclinical and human research about the actions of CBD on the effects of stimulant drugs, mainly cocaine and methamphetamine (METH). Additionally, the possible mechanisms underlying the therapeutic potential of CBD on stimulant use disorders are reviewed. CBD has reversed toxicity and seizures induced by cocaine, behavioural sensitization induced by amphetamines, motivation to self-administer cocaine and METH, context- …
Salts of 5-amino-2-sulfonamide-1,3,4-thiadiazole, a structural and analog of acetazolamide, show interesting carbonic anhydrase inhibitory properties…
2015
Three salts of 5-amino-2-sulfonamide-1,3,4-thiadiazole (Hats) were prepared and characterized by physico-chemical methods. The p-toluensulfonate, the methylsulfonate, and the chlorhydrate monohydrate salts of Hats were evaluated as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors (CAIs) and as anticonvulsants and diuretics, since many CAIs are clinically used as pharmacological agents. The three Hats salts exhibited diuretic and anticonvulsant activities with little neurotoxicity. The human (h) isoforms hCA I, II, IV, VII, IX, and XII were inhibited in their micromolar range by these salts, whereas pathogenic beta and gamma CAs showed similar, weak inhibitory profiles.
Hyperstoichiometric interaction between silver and mercury at the nanoscale.
2012
Breaking through the stoichiometry barrier: As the diameter of silver particles is decreased below a critical size of 32?nm, the molar ratio of aqueous HgII to Ag0 drastically increases beyond the conventional Hg/Ag ratio of 0.5:1, leading to hyperstoichiometry with a maximum ratio of 1.125:1 (see figure). Therein, around 99?% of the initial silver is retained to rapidly form a solid amalgam with reduced mercury.
Inorganic Mercury Sequestration by a Poly(ethylene imine) Dendrimer in Aqueous Solution
2015
The interaction of the G-2 poly(ethylene imine) dendrimer L, derived from ammonia as initiating core, with Hg(II) and HgCl4 2− was studied in aqueous solution by means of potentiometric (pH-metric) measurements. Speciation of these complex systems showed that L is able to form a wide variety of complexes including 1:1, 2:1, 3:1 and 3:2 metal-to-ligand species, of different protonation states, as well as the anion complexes ((H7L)HgCl4) 5+ and ((H8L)HgCl4) 6+ . The stability of the metal complexes is very high, making L an excellent sequestering agent for Hg(II), over a large pH range, and a promising ligand for the preparation of functionalized activated carbons to be employed in the remedi…
Fecal Metagenomics and Metabolomics Identifying Microbial Signatures in Non-Alcoholic Fatty Liver Disease
2023
The frequency of non-alcoholic fatty liver disease (NAFLD) has intensified, creating diagnostic challenges and increasing the need for reliable non-invasive diagnostic tools. Due to the importance of the gut–liver axis in the progression of NAFLD, studies attempt to reveal microbial signatures in NAFLD, evaluate them as diagnostic biomarkers, and to predict disease progression. The gut microbiome affects human physiology by processing the ingested food into bioactive metabolites. These molecules can penetrate the portal vein and the liver to promote or prevent hepatic fat accumulation. Here, the findings of human fecal metagenomic and metabolomic studies relating to NAFLD are reviewed. The …
Cross-Linked Thiazolidine Network as Support for Palladium: A New Catalyst for Suzuki and Heck Reactions
2015
A thiazolidine-based material was used for the first time as support for palladium. The support was prepared by starting from a highly cross-linked thiazolium-based material, obtained by radical oligomerization of a bisvinylthiazolium dibromide salt in the presence of 3-mercaptopropyl-modified silica SBA-15. Palladium was immobilized by treatment with tetrachloropalladate salt. Reduction with sodium borohydride afforded a thiazolidine-based material that acted as ligands for the Pd species. The thiazolidine-based palladium catalyst was fully characterized and, working in only 0.1 mol% amount, displayed good activity in the Suzuki-Miyaura and in the Heck reactions. Several biphenyl and alken…