Search results for "aminoacid"
showing 10 items of 39 documents
Partially competitive inhibition of intestinal baclofen absorption by beta-alanine, a nonessential dietary aminoacid.
1991
In situ intestinal absorption of baclofen in the rat in the presence of beta-alanine has been investigated. Through the perfusion of 0.50 mM baclofen solutions containing variable concentrations of the aminoacid (from 5 to 100 mM), a partially competitive inhibition of baclofen absorption was characterized: absorption rate pseudoconstants of the spasmolytic drug decrease as beta-alanine concentration increases, until a limiting value is obtained (36.8 per cent of that found for baclofen alone). A computer method was developed in order to calculate parameters governing baclofen absorption in the presence of beta-aminoacid, with the following results: Vm = 11.22 mM h-1; Km = 7.42 mM; Ki = 2.4…
In Lysinuric Protein Intolerance system y+L activity is defective in monocytes and in GM-CSF-differentiated macrophages
2010
Abstract Background In the recessive aminoaciduria Lysinuric Protein Intolerance (LPI), mutations of SLC7A7/y+LAT1 impair system y+L transport activity for cationic amino acids. A severe complication of LPI is a form of Pulmonary Alveolar Proteinosis (PAP), in which alveolar spaces are filled with lipoproteinaceous material because of the impaired surfactant clearance by resident macrophages. The pathogenesis of LPI-associated PAP remains still obscure. The present study investigates for the first time the expression and function of y+LAT1 in monocytes and macrophages isolated from a patient affected by LPI-associated PAP. A comparison with mesenchymal cells from the same subject has been a…
Association between M467T and 114 C--A variants within the SLC3A1 gene and some phenotypical traits in cystinuria patients from Spain.
2000
Cystinuria is an inherited metabolic disease characterized by an abnormal urinary excretion of cystine and dibasic amino acids. Formation of renal calculi, recurrent infections and renal failure are the main complications of this disease. The SLC3A1 gene, which codes for a dibasic amino acid transporter protein, is involved in the pathogenesis of cystinuria. We investigated the possible association between molecular variants (M467T, E483X, T216 M and 114 C--A) within the SLC3A1 gene and some phenotypical traits in a Spanish area. The study population consisted of 45 cystinuria patients, 42 cystinuria relatives and 81 healthy control subjects. Only the M467T mutation was found in chromosomes…
Synthesis, characterisation and complexation of di- and trifunctional hybrid ferrocenylphosphine ligands.
2020
Organometallic compounds with at least one metal-carbon bond are used in various fields of chemistry: for example, in medical research for anticancer treatments, in catalytic reactions as catalysts or ligands, in electrochemistry for their redox potentials, in materials chemistry for their optical and electronic properties. The principal family of organometallic compounds of this thesis is ferrocene due to its physical and chemical properties particularly its robustness and the possibility of multiple substitutions on cyclopentadienyl ligands, the dissymmetric functionalization of these cyclopentadienyl rings being a major challenge.The first part of this thesis describes the bibliography o…
A NEW DOPAMINE-AMINOACID CONJUGATE: SYNTHESIS AND DETERMINATION OF PHYSICO-CHEMICAL PROPERTIES USEFUL TO CROSS THE BBB
2012
N-valproyl-aminoacids as new potential antiepileptic drugs: Synthesis, characterization and in vitro studies on stability
2015
Epilepsy, affecting at least 50 million persons worldwide, is one of the most common neurological disorders. Despite the significant advances in understanding epileptogenic mechanisms and in counteracting their pathological consequences, this clinical condition still has to be faced of treating more effectively the symptoms (epileptic seizures) and of preventing their unfavourable evolution. So far, research has been unsuccessful involved in developing effective antiepileptic drugs (AEDs) capable of preventing the development of the pathogenic process, set in motion by different etiological factors, that leads ultimately to chronic epilepsies .[1, 2] So, a substantial need remains to develo…
An Efficient Synthesis of γ-Aminoacids and Attempts to Drive Its Enantioselectivity
2008
Addition of carboxylic acid dianions to bromoacetonitrile lead, in good yields,to the corresponding gamma-cyanoacids, which on hydrogenation yielded gamma-amino acids. This two step methodology improves upon previously described results. Poor e.e's resultedfrom our attempts to drive the enantioselectivity of this transformation by chiral amide induction.
A facile way to build up branched high functional polyaminoacids with tunable physicochemical and biological properties
2016
Abstract Here, for the first time, branched polyaminoacids bearing α-amino acids as side functions, namely PAA-co-AA and PGA-co-AA, are prepared by heterophase ring opening of polysuccinimide (PSI) with l -arginine or glycine in aqueous environment and at controlled pH. The modulation of the pH of the reaction leads to high-molecular-weight copolymers with tunable functionalization and, as consequence, with tailor-made physicochemical properties. Furthermore, a branched polyaminoacid carrying a preformed bioactive peptide ( l -trileucine) and l -arginine as side pendants, named PATA-co-AA, was synthesized via a similar pathway thus leading to complex biomimetic materials potentially exploit…
Complessi di Organostagno(IV) con amminoacidi e dipeptidi: sintesi, caratterizzazione e attività biologica in vitro.
2008
Scopo della ricerca è la sintesi, caratterizzazione strutturale ed attività biologica di complessi di organostagno(IV) e amminoacidi quali L-arginina (Arg), N-Boc-L-arginina (Boc-Arg), L-ornitina (L-Orn) ed un dipeptide contenente L-arginina, Alanil-Arginina (Ala-Arg). I complessi di diorganostagno(IV) sono noti possedere attività antitumorale [1], antimicrobica [2] e antiinfiammatoria. I complessi di triorganostagno(IV) inibiscono la funzione mitocondriale almeno in tre modi: 1) reagendo con le membrane cellulari; 2) alterando lo scambio Cl-/OH- attraverso la membrana; 3) inibendo la fosforilazione ossidativa o l’idrolisi di ATP [3].L’arginina (Arg) è un amminoacido essenziale con un grup…