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1.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 6): 798-802, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32523742

RESUMO

The asymmetric unit of the title compound, C17H14N2O, contains two independent mol-ecules each consisting of perimidine and phenol units. The tricyclic perimidine units contain naphthalene ring systems and non-planar C4N2 rings adopting envelope conformations with the C atoms of the NCN groups hinged by 44.11 (7) and 48.50 (6)° with respect to the best planes of the other five atoms. Intra-molecular O-H⋯N hydrogen bonds may help to consolidate the mol-ecular conformations. The two independent mol-ecules are linked through an N-H⋯O hydrogen bond. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (52.9%) and H⋯C/C⋯H (39.5%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Density functional theory (DFT) optimized structures at the B3LYP/ 6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

2.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 5): 605-610, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32431917

RESUMO

The title compound, C18H16N2O2, consists of perimidine and meth-oxy-phenol units, where the tricyclic perimidine unit contains a naphthalene ring system and a non-planar C4N2 ring adopting an envelope conformation with the NCN group hinged by 47.44 (7)° with respect to the best plane of the other five atoms. In the crystal, O-HPhnl⋯NPrmdn and N-HPrmdn⋯OPhnl (Phnl = phenol and Prmdn = perimidine) hydrogen bonds link the mol-ecules into infinite chains along the b-axis direction. Weak C-H⋯π inter-actions may further stabilize the crystal structure. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (49.0%), H⋯C/C⋯H (35.8%) and H⋯O/O⋯H (12.0%) inter-actions. Hydrogen bonding and van der Waals inter-actions are the dominant inter-actions in the crystal packing. Computational chemistry indicates that in the crystal, the O-HPhnl⋯NPrmdn and N-HPrmdn⋯OPhnl hydrogen-bond energies are 58.4 and 38.0 kJ mol-1, respectively. Density functional theory (DFT) optimized structures at the B3LYP/ 6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behaviour was elucidated to determine the energy gap.

3.
Biomaterials ; 175: 1-18, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29793088

RESUMO

Surgical resection of the esophagus requires sacrificing a long portion of it. Its replacement by the demanding gastric pull-up or colonic interposition techniques may be avoided by using short biologic scaffolds composed of decellularized matrix (DM). The aim of this study was to prepare, characterize, and assess the in vivo remodeling of DM and its clinical impact in a preclinical model. A dynamic chemical and enzymatic decellularization protocol of porcine esophagus was set up and optimized. The resulting DM was mechanically and biologically characterized by DNA quantification, histology, and histomorphometry techniques. Then, in vitro and in vivo tests were performed, such as DM recellularization with human or porcine adipose-derived stem cells, or porcine stromal vascular fraction, and maturation in rat omentum. Finally, the DM, matured or not, was implanted as a 5-cm-long esophagus substitute in an esophagectomized pig model. The developed protocol for esophageal DM fulfilled previously established criteria of decellularization and resulted in a scaffold that maintained important biologic components and an ultrastructure consistent with a basement membrane complex. In vivo implantation was compatible with life without major clinical complications. The DM's scaffold in vitro characteristics and in vivo implantation showed a pattern of constructive remodeling mimicking major native esophageal characteristics.


Assuntos
Materiais Biocompatíveis/química , Esôfago , Matriz Extracelular/química , Alicerces Teciduais/química , Tecido Adiposo/citologia , Animais , Fenômenos Biomecânicos , Adesão Celular , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , DNA/análise , Esôfago/química , Esôfago/citologia , Esôfago/metabolismo , Humanos , Masculino , Estudo de Prova de Conceito , Próteses e Implantes , Ratos Nus , Ratos Wistar , Células-Tronco/citologia , Células-Tronco/fisiologia , Suínos , Engenharia Tecidual
4.
Food Chem Toxicol ; 112: 134-144, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29288758

RESUMO

Ficus exasperata Vahl, commonly known as sandpaper, is a terrestrial Afro-tropical tree used in popular medicine. Despite the existence of some works on the biological activities of this species, its chemical composition is still poorly known. The aim of this study was to extend the knowledge on the phytochemistry and biological properties of this species. Aqueous extracts from F. exasperata leaves and stem bark were analysed. Thirty-one phenolic compounds, comprising cinnamoyl derivatives, flavonoid-O-glycosides, flavonoid-mono-C-glycosides, flavonoid-di-C-glycosides and one furanocoumarin, were determined by HPLC-DAD-ESI/MSn and UPLC-ESI-QTOF-MS, 26 of them being reported for the first time in this species. The profile of organic acids, characterized by HPLC-UV, was also reported for the first time. The best radical scavenging activity was observed for the aqueous extract from leaves (IC50 values of 222.5, 510.0 and 50.0 µg/mL against DPPH•, •NO and O2•-, respectively). In addition, both aqueous extracts of the leaves and stem bark displayed a weak effect on α-amylase, and no cytotoxicity against gastric adenocarcinoma cell line, AGS. This study contributes to the valorisation of these vegetal materials, which may have application in functional foods and/or nutraceuticals.


Assuntos
Ficus/química , Sequestradores de Radicais Livres/farmacologia , Casca de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/química , Alimento Funcional , Humanos , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Óxido Nítrico/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Ultravioleta , Superóxidos/química
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