Comorbilidad Compleja en TCA: Un Caso de Síndrome de Marchiafava-Bignami

Póster presentado en las XI Jornadas Internacionales sobre Trastornos de la Conducta Alimentaria (TCA), celebradas en Valencia del 7 al 9 de noviembre de 2018La atención a los trastornos de la conducta alimentaria (TCA) va ligada a una supervisión de la salud física de los pacientes. La cronicidad y gravedad hacen que desarrollen comorbilidades complejas cuyo diagnóstico y abordaje pueden ser difíciles. A continuación se expone el caso clínico de una paciente con Anorexia Nerviosa (AN) crónica complicada por un diagnóstico neurológico que dificulta su tratamiento, el Síndrome de Marchiafava-Bignami (SMB). Se trata de una enfermedad neurológica muy poco frecuente cuya etiología se atribuye a estados de desnutrición y los efectos neurotóxicos del alcohol. Clínicamente puede cursar con deterioro cognitivo y demencia, espasticidad, disartria, convulsiones y síntomas de desconexión interhemisférica. El diagnóstico se establece mediante la identificación de lesiones características en RMN seriadas (especialmente localizadas en el cuerpo calloso). No existe tratamiento específico y el pronóstico es variable alternando entre la remisión completa, la cronicidad del cuadro y la muerte

Foldamers of β-peptides : conformational preference of peptides formed by rigid building blocks : The first MI-IR spectra of a triamide nanosystem

To determine local chirality driven conformational preferences of small aminocyclobutane-1-carboxylic acid derivatives, X-(ACBA) n -Y, their matrix-isolation IR spectra were recorded and analyzed. For the very first time model systems of this kind were deposited in a frozen (~10 K) noble gas matrix to reduce line width and thus, the recorded sharp vibrational lines were analyzed in details. For cis-(S,R)-1 monomer two “zigzag” conformers composed of either a six or an eight-membered H-bonded pseudo ring was identified. For trans-(S,S)-2 stereoisomer a zigzag of an eight-membered pseudo ring and a helical building unit were determined. Both findings are fully consistent with our computational results, even though the relative conformational ratios were found to vary with respect to measurements. For the dimers (S,R,S,S)-3 and (S,S,S,R)-4 as many as four different cis,trans and three different trans,cis conformers were localized in their matrix-isolation IR (MI-IR) spectra. These foldamers not only agree with the previous computational and NMR results, but also unambiguously show for the first time the presence of a structure made of a cis,trans conformer which links a “zigzag” and a helical foldamer via a bifurcated H-bond. The present work underlines the importance of MI-IR spectroscopy, applied for the first time for triamides to analyze the conformational pool of small biomolecules. We have shown that the local chirality of a β-amino acid can fully control its backbone folding preferences. Unlike proteogenic α-peptides, β- and especially (ACBA) n type oligopeptides could thus be used to rationally design and influence foldamer’s structural preferences

Reaction between N-alkylhydroxylamines and chiral enoate esters: More experimental evidence for a cycloaddition-like process, a rationale based on DFT theoretical calculations, and stereoselective synthesis of new enantiopure β-amino acids

The reactions between N-benzyl- and N-methylhydroxylamine and chiral enoate esters, derived from D-glyceraldehyde and (-)-verbenone, respectively, have been investigated. Theoretical calculations show that the most favorable mechanism involves the concerted cycloaddition of the hydroxylamine to the substrate. This result is in good agreement with the stereospecificity observed when the trisubstituted olefins are used. The open-chain adducts have been isolated when the processes are carried out at low temperatures and for short reaction times. These compounds evolve to the corresponding isoxazolidinones on standing at room temperature or under acid catalysis. The high π-facial diastereoselection has been rationalized on the basis of steric effects induced by the dioxolane ring for D-glyceraldehyde derivatives or by the cyclobutane gem-dimethyl substitution for esters prepared from (-)-verbenone. As an application of these reactions, new β-amino acids have been synthesized in a highly efficient and stereocontrolled manner.Fil: Moglioni, Albertina Gladys. Universitat Autònoma de Barcelona; España. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; ArgentinaFil: Muray, Elena. Universitat Autònoma de Barcelona; EspañaFil: Castillo, José A.. Universitat Autònoma de Barcelona; EspañaFil: Álvarez Larena, Ángel. Universitat Autònoma de Barcelona; EspañaFil: Moltrasio, Graciela Y.. Universidad de Buenos Aires; ArgentinaFil: Branchadell, Vicenç. Universitat Autònoma de Barcelona; EspañaFil: Ortuño, Rosa M.. Universitat Autònoma de Barcelona; Españ