Search results for "Amines"
showing 10 items of 664 documents
N-Methyl-4-(4-nitrophenyl)-N-nitroso-1,3-thiazol-2-amine
2017
The title compound, C10H8N4O3S, is almost planar [dihedral angle between the rings = 2.2 (2)°; r.m.s. deviation for the non-H atoms = 0.050 Å]. In the crystal, C—H...O and C—H...N hydrogen bonds link the molecules into (10-2) layers.
Methionine Cycle Rewiring by Targeting miR-873-5p Modulates Ammonia Metabolism to Protect the Liver from Acetaminophen
2022
Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-adminis…
Illicit drugs consumption evaluation by wastewater-based epidemiology in the urban area of Palermo city (Italy)
2017
Introduction. A wastewater-based epidemiology approach was performed to estimate the drug consumption in Palermo city, the fifth largest city of Italy with a population of 671 696 inhabitants, and to investigate the monthly variability of drug loads in wastewater from different areas of the city. A seven-months detection campaign was conducted at the two wastewater treatment plants of the city. Methods. Following a pre-treatment, 32 samples of wastewater were analyzed by liquid chromatography-tandem mass spectrometry. Results. We estimated a mean cocaine use in Palermo of 0.19 g/day/1000 people, corresponding to 1.90 doses/1000 people and cannabinoids use of 2.85 g/day/1000 people, correspo…
Evolution of Free Amino Acids, Histamine and Volatile Compounds in the Italian Anchovies (Engraulis encrasicolus L.) Sauce at Different Ripening Times
2022
In this study, the evolution of the safety, nutritional, and volatile profile of a traditional Italian anchovy sauce with protected designation of origin (PDO), called “colatura di alici di Cetara”, is investigated after 12, 24, and 48 months of aging in wooden barrels. Some physicochemical parameters, free amino acids, volatile compounds, and histamine contents were evaluated during the aging of the samples. Glutamate, which together with aspartate is responsible for the umami taste, was the predominant free amino acid in the tested fish sauce, with a significant increase during the 48 months of maturation. The total amino acid content of the anchovy sauce increased from 24 to …
Fruits and vegetables protect against the genotoxicity of heterocyclic aromatic amines activated by human xenobiotic-metabolizing enzymes expressed i…
2010
Heterocyclic aromatic amines (HAAs) can be formed during the cooking of meat and fish at elevated temperatures and are associated with an increased risk for cancer. On the other hand, epidemiological findings suggest that foods rich in fruits and vegetables can protect against cancer. In the present study three teas, two wines, and the juices of 15 fruits and 11 vegetables were investigated for their protective effect against the genotoxic effects of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). To closely mimic the enzymatic activation of these HAAs in humans, genetically engineered V79 Chinese hamster fibroblasts were employed tha…
Polyamines and ripening of photoreceptor outer segments in chicken embryos.
1995
Abstract Polyamines and their related monoacetyl derivatives were studied in rod outer segment (ROS) and cone outer segment (COS) of photoreceptor cells from chick embryo retina during eye development (7th–18th days). Putrescine was found to be necessary, in the second phase of retinogenesis, to sustain both ROS and COS differentiation and, after acetylation, γ-aminobutyric acid synthesis. On the other hand, spermidine and even more spermine intervene in the third phase of development when photoreceptors mature. Moreover, the presence of N1-acetylspermidine already at the 7th day indicates that in the outer segment of photoreceptor cells too, as in the whole retina, putrescine synthesis com…
Single hollow fiber SLM extraction of polyamines followed by tosyl chloride derivatization and HPLC determination
2007
Determination of polyamines in biological fluids possesses medical diagnostic relevance. Despite the vast panel of analytical methods developed for polyamines they are not applied in routine clinical usage, mainly due to the time and labor consuming sample preparation step and complicated derivatization procedures. Thus, new simpler methods are needed. This paper describes a single hollow fiber SLM extraction method of polyamines followed by simple pre-column derivatization with tosyl chloride and HPLC-UV analysis. The influence of different parameters such as the extraction time, organic phase composition, acceptor pH, donor pH, acceptor volume, donor volume and stirring speed on the trans…
Actualisation des références nutritionnelles françaises en vitamines et minéraux
2021
En 2016, l’Anses a proposé une mise à jour des références nutritionnelles pour la population adulte (femmes de 18 à 54 ans et hommes de 18 à 64 ans) dans le cadre de l’actualisation des repères de consommation alimentaire (saisine 2012-SA-0103). Par la suite, des rapports dédiés aux repères de consommation alimentaire pour les populations spécifiques (personnes âgées, enfants, femmes enceintes et allaitantes) ont été publiés en 2019, sans toutefois quede nouvelles références nutritionnelles ne soient définies par l’agence.Par ailleurs, la mise à jour de 2016 n’a concerné que les vitamines et minéraux indispensables pour lesquelles des données de consommation étaient disponibles. De ce fait,…
Facile Synthesis of Fluorescent Polymer Nanoparticles by Covalent Modification-Nanoprecipitation of Amine-Reactive Ester Polymers
2015
Emission wavelength control in fluorescent nanoparticles (NPs) is crucial for their applications. In the case of inorganic quantum dots or dye-impregnated silica NPs, such a control is readily achieved by changing the size of the particles or choosing appropriate fluorescent dyes, respectively. A similar modular approach for controlling the emission wavelength of fluo-rescent polymer NPs, however, is difficult. This article reports on fluorescent polymer NPs, the synthesis of which provides a platform for a modular approach towards the preparation of fluorescent NPs of desired emission wavelength. Atom-transfer radical polymerization (ATRP) is employed to synthesize reactive ester polymers,…
Study of aromatic nucleophilic substitution with amines on nitrothiophenes in RTILs: are the different effects on the behavior of para-like and orto-…
2006
The kinetics of the nucleophilic aromatic substitution of some 2-L-5-nitrothiophenes (para-like isomers) with three different amines (pyrrolidine, piperidine, and morpholine) were studied in three roomtemperature ionic liquids ([bmim][BF4], [bmim][PF6], and [bm2im][BF4], where bmim ) 1-butyl-3- methylimidazolium and bm2im ) 1-butyl-2,3-dimethylimidazolium). To calculate thermodynamic parameters, a useful instrument to gain information concerning reagent-solvent interactions, the reaction was carried out over the temperature range 293-313 K. The reaction occurs faster in ionic liquids than in conventional solvents (methanol, benzene), a dependence of rate constants on amine concentration sim…