Sample records for conformational changes
from WorldWideScience.org

Sample records 1 - 2 shown.



1

Espectro infravermelho e análise conformacional do composto 3-fenil-2-oxo-1,2,3-oxatiazolidina/ A semiempirical infra-red spectrum of the 3-phenyl - 1,2,3 - oxathiazolidine 2-oxide

Santos, Hélio F. dos; Almeida, Wagner B. de; Val, Amélia M. G. do; Guimarães, Afonso C.
1999-09-01

Resumo em inglês The infrared (IR) spectra of the four distict conformers located on the multidimensional potential energy surface (PES) for the 3-phenyl-1,2,3-oxathiazolidine 2-oxide compound have been calculated using the semiempirical quantum-mechanical method PM3. The band spectra are reported and compared directly with the experimental spectrum. The IR intensities are shown to be much more sensitive to conformational changes than the vibrational frequencies and so, the theoretical an (mais) alysis of the IR spectrum can be used as a tool for helping in the elucidation of the structure of heterocyclic compounds.

Scientific Electronic Library Online (Portuguese)

2

Adsorção de fibronectina a arcabouços de polihidroxibutirato aplicáveis à engenharia óssea/ Adsorption of fibronectin onto polyhydroxybutyrate scaffolds applied to bone engineering

Mendonça, Roberta H.; Thiré, Rossana M. S. M.; Costa, Marysilvia F. da; S. Filho, Fernando C.
2009-06-01

Resumo em português Fibronectina sérica humana foi adicionada à superfície de arcabouços de polihidroxibutirato (PHB) a fim de otimizar a adesão de osteoblastos humanos (HOB). Visando a criar sítios para a imobilização de fibronectina (FN), os arcabouços foram previamente tratados por meio de reação com etilenodiamina. O tratamento modificou a morfologia e a composição química dos arcabouços, possibilitando um aumento no teor de FN adsorvido à superfície. Imagens de AFM most (mais) raram que as moléculas de FN assumiram conformações distintas, de acordo com a superfície na qual foi imobilizada. A FN adicionada aos arcabouços não modificados possivelmente assumiu uma conformação estendida, expondo os grupamentos RGD. Com isso, houve um aumento na adesão de HOB a estes materiais. Por outro lado, a FN na superfície dos arcabouços previamente tratados possivelmente apresentou-se na forma compacta, suprimindo a adesão de HOB. Resumo em inglês Human plasma fibronectin (FN) was adsorbed onto the surface of polyhydroxybutyrate (PHB) scaffolds with aim of improving adhesion of human osteoblasts (HOB). PHB scaffolds were modified via reaction with ethylenediamine in order to create sites for FN immobilization. Morphological and chemical composition changes were observed for treated scaffolds which led to an increase in the concentration of FN adsorbed onto scaffold surfaces. AFM images showed that FN molecules assu (mais) med distinct conformation according to the surface to which they were adsorbed. It is believed that the FN molecules added to non-treated scaffolds assumed an unfolded conformational owing to the exposure of their RGD domains, thus promoting an increased HOB adhesion. On the other hand, FN molecules which were added to the surface of previously treated scaffolds are believed to have assumed a folded conformation, hiding some RGD domains and inhibiting HOB adhesion.

Scientific Electronic Library Online (Portuguese)