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.
J Dairy Sci ; 99(4): 2502-2511, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26852809

RESUMO

Many health authorities have targeted salt reduction in food products as a means to reduce dietary sodium intake due to the harmful effects associated with its excessive consumption. In the present work, we evaluated the effect of reducing sodium chloride (NaCl) content on the microbiological and biochemical characteristics of an experimental surface-ripened cheese. A control cheese (1.8% NaCl) and a cheese with a reduced NaCl content (1.3% NaCl) were sampled weekly over a period of 27d. Reducing NaCl content induced microbial perturbations such as the lesser development of the yeast Debaryomyces hansenii and the greater development of the gram-negative bacterium Hafnia alvei. This was accompanied by changes in proteolytic kinetics and in profiles of volatile aroma compounds and biogenic amine production. Finally, the development of the spoilage microorganism Pseudomonas fragi was significantly higher in the cheese with a reduced salt content.


Assuntos
Queijo/microbiologia , Pseudomonas fragi/efeitos dos fármacos , Cloreto de Sódio na Dieta/farmacologia , Cloreto de Sódio/química , Animais , Aminas Biogênicas/análise , Queijo/análise , Cinética , Proteólise , Pseudomonas fragi/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/análise
2.
Oncogene ; 35(30): 3976-85, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-26686091

RESUMO

Photosensitizers (PS) are ideally devoid of any activity in the absence of photoactivation, and rely on molecular oxygen for the formation of singlet oxygen ((1)O2) to produce cellular damage. Off-targets and tumor hypoxia therefore represent obstacles for the use of PS for cancer photodynamic therapy. Herein, we describe the characterization of OR141, a benzophenazine compound identified through a phenotypic screening for its capacity to be strictly activated by light and to kill a large variety of tumor cells under both normoxia and hypoxia. This new class of PS unraveled an unsuspected common mechanism of action for PS that involves the combined inhibition of the mammalian target of rapamycin (mTOR) signaling pathway and proteasomal deubiquitinases (DUBs) USP14 and UCH37. Oxidation of mTOR and other endoplasmic reticulum (ER)-associated proteins drives the early formation of high molecular weight (MW) complexes of multimeric proteins, the concomitant blockade of DUBs preventing their degradation and precipitating cell death. Furthermore, we validated the antitumor effects of OR141 in vivo and documented its highly selective accumulation in the ER, further increasing the ER stress resulting from (1)O2 generation upon light activation.


Assuntos
Enzimas Desubiquitinantes/antagonistas & inibidores , Retículo Endoplasmático/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Oxigênio/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias/metabolismo , Oxirredução , Complexo de Endopeptidases do Proteassoma/metabolismo , Serina-Treonina Quinases TOR/fisiologia
3.
J Ethnopharmacol ; 133(1): 108-15, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-20858541

RESUMO

AIM OF THE STUDY: Noni fruit (Morinda citrifolia L.) juice has been used for more than 2000 years in Polynesia as a traditional folk medicine. The aim of the present study was to finely characterize noni juice from Costa Rica and to evaluate its anti-oxidative and anti-inflammatory activities. MATERIALS AND METHODS: A microfiltrated noni juice was prepared with Costarican nonis. HPLC-DAD and Electro Spray Ionization Mass Spectrometric detection (HPLC-ESI-MS) were used to identify phenolic compounds and iridoids. The anti-oxidative activity of noni juice was measured in vitro by both Oxygen Radical Absorbance Capacity (ORAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging methods. The anti-inflammatory effects of noni juice were investigated in vitro by: measuring its effect on nitric oxide and prostaglandin E2 production by activated macrophages, evaluating its inhibitory activities on cyclooxygenase (COX)-1 and -2 and in vivo on a carrageenan-induced paw oedema model in rats. RESULTS: Several polyphenols belonging to the coumarin, flavonoid and phenolic acid groups, and two iridoids were identified. Noni juice demonstrated a mean range free radical scavenging capacity. Furthermore, it also reduced carrageenan-induced paw oedema, directly inhibited cyclooxygenase COX-1 and COX-2 activities and inhibited the production of nitric oxide (NO) and prostaglandins E(2) (PGE(2)) in activated J774 cells, in a dose dependent manner. CONCLUSIONS: This study showed that noni's biological effects include: (1) anti-oxidant properties probably associated with phenolic compounds, iridoids and ascorbic acid and (2) anti-inflammatory action through NO and PGE(2) pathways that might also be strengthened by anti-oxidant effects.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Morinda , Fenóis/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Antioxidantes/química , Bebidas , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Costa Rica , Flavonoides/análise , Frutas , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Oxirredução , Fenóis/análise , Extratos Vegetais/química , Polifenóis , Ratos , Ratos Wistar
4.
Nucleic Acids Res ; 12(22): 8595-609, 1984 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-6504704

RESUMO

Electron microscopic analysis of heteroduplexes between the most distantly related Xenopus vitellogenin genes (A genes X B genes) has revealed the distribution of homologous regions that have been preferentially conserved after the duplication events that gave rise to the multigene family in Xenopus laevis. DNA sequence analysis was limited to the region downstream of the transcription initiation site of the Xenopus genes A1, B1 and B2 and a comparison with the Xenopus A2 and the major chicken vitellogenin gene is presented. Within the coding regions of the first three exons, nucleotide substitutions resulting in amino acid changes accumulate at a rate similar to that observed in globin genes. This suggests that the duplication event which led to the formation of the A and B ancestral genes in Xenopus laevis occurred about 150 million years ago. Homologous exons of the A1-A2 and B1-B2 gene pairs, which formed about 30 million years ago, show a quite similar sequence divergence. In contrast, A1-A2 homologous introns seem to have evolved much faster than their B1-B2 counterparts.


Assuntos
Evolução Biológica , Genes , Lipoproteínas/genética , Transcrição Gênica , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Galinhas , Clonagem Molecular , Microscopia Eletrônica , Especificidade da Espécie , Xenopus
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...