Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 9(11): e109972, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25365555

RESUMO

Celiac disease (CD) is an autoimmune disorder in individuals that carry DQ2 or DQ8 MHC class II haplotypes, triggered by the ingestion of gluten. There is no current treatment other than a gluten-free diet (GFD). We have previously shown that the BL-7010 copolymer poly(hydroxyethyl methacrylate-co-styrene sulfonate) (P(HEMA-co-SS)) binds with higher efficiency to gliadin than to other proteins present in the small intestine, ameliorating gliadin-induced pathology in the HLA-HCD4/DQ8 model of gluten sensitivity. The aim of this study was to investigate the efficiency of two batches of BL-7010 to interact with gliadin, essential vitamins and digestive enzymes not previously tested, and to assess the ability of the copolymer to reduce gluten-associated pathology using the NOD-DQ8 mouse model, which exhibits more significant small intestinal damage when challenged with gluten than HCD4/DQ8 mice. In addition, the safety and systemic exposure of BL-7010 was evaluated in vivo (in rats) and in vitro (genetic toxicity studies). In vitro binding data showed that BL-7010 interacted with high affinity with gliadin and that BL-7010 had no interaction with the tested vitamins and digestive enzymes. BL-7010 was effective at preventing gluten-induced decreases in villus-to-crypt ratios, intraepithelial lymphocytosis and alterations in paracellular permeability and putative anion transporter-1 mRNA expression in the small intestine. In rats, BL-7010 was well-tolerated and safe following 14 days of daily repeated administration of 3000 mg/kg. BL-7010 did not exhibit any mutagenic effect in the genetic toxicity studies. Using complementary animal models and chronic gluten exposure the results demonstrate that administration of BL-7010 is effective and safe and that it is able to decrease pathology associated with gliadin sensitization warranting the progression to Phase I trials in humans.


Assuntos
Doença Celíaca/imunologia , Gliadina/imunologia , Poli-Hidroxietil Metacrilato/análogos & derivados , Poliestirenos/farmacologia , Animais , Doença Celíaca/tratamento farmacológico , Doença Celíaca/patologia , Modelos Animais de Doenças , Feminino , Gliadina/metabolismo , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Transgênicos , Permeabilidade , Poli-Hidroxietil Metacrilato/síntese química , Poli-Hidroxietil Metacrilato/metabolismo , Poli-Hidroxietil Metacrilato/farmacologia , Poliestirenos/síntese química , Poliestirenos/metabolismo , Ligação Proteica , Ratos , Testes de Toxicidade
3.
Chem Commun (Camb) ; (18): 2149-51, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18438498

RESUMO

The first synthesis of achiral and chiral [ONNO']-type Salan ligands featuring two different phenol arms, and the diastereoselective formation of the corresponding octahedral C1-symmetric zirconium complexes is described; the activity and isospecificity induction of the [ONNO']Zr(bn)2 complexes in 1-hexene polymerisation reflected those of the parent symmetric compounds.


Assuntos
Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Zircônio/química , Catálise , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular , Estereoisomerismo
4.
Inorg Chem ; 46(20): 8114-6, 2007 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-17824700

RESUMO

A straightforward synthesis of a new type of tetradentate dianionic [OSSO]-type ligand is described. This ligand features an ethylenedithiol core bridged via methylene groups to substituted phenols, thus representing an S analogue of the [ONNO]-type Salan ligands. The [OSSO]H2 ligand precursor reacted with titanium(IV) isopropoxide and with zirconium(IV) tert-butoxide to give the corresponding [OSSO]-M(OR)2 complexes, which formed as single C2-symmetric isomers but were fluxional according to variable-temperature NMR. An X-ray structure of [OSSO]-Zr(O-t-Bu)2 supported the fac-fac wrapping mode of the ligand. The dibenzyl complex [OSSO]-Zr(bn)2 that was obtained by a reaction between the ligand precursor and tetrabenzylzirconium was found to be an active 1-hexene polymerization catalyst upon activation with B(C6F5)3, leading to a stereoirregular polymer despite its C2 symmetry.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA