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1.
Arch Biochem Biophys ; 433(2): 421-7, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15581598

RESUMO

The main objective of this study was to compare the protective effect of daidzein and genistein against induced oxidative damage in Jurkat T-cell line and in peripheral blood lymphocytes of healthy subjects. After supplementation of cells with isoflavones (from 2.5 to 20micromol/L in Jurkat T-cell and from 0.01 to 2.5micromol/L in primary lymphocytes, 24h), we determined DNA damage induced by hydrogen peroxide using the comet assay and lipid peroxidation evaluating malondialdehyde (MDA) production after ferrous ion treatment. Supplementation of Jurkat cells and primary lymphocytes with both isoflavones significantly increased DNA protection from oxidative damage at concentrations between 0.1 and 5micromol/L (P<0.05), and with just daidzein, at concentrations higher than 2.5micromol/L, there was a decrease in the production of MDA (P<0.05). Our results seem to support that daidzein is just as effective as genistein in protecting cells against oxidative damage especially with respect to DNA. Moreover, since the protective effect was found at concentrations reachable in plasma after soy consumption (less than 2micromol/L), it can be assumed that the antioxidant activity of isoflavones could really contribute to the healthy properties of soy.


Assuntos
Antioxidantes/farmacologia , Genisteína/farmacologia , Isoflavonas/farmacologia , Fitoestrógenos/farmacologia , Linfócitos T/efeitos dos fármacos , Linhagem Celular Transformada , Células Cultivadas , Ensaio Cometa , Testes Imunológicos de Citotoxicidade , Dano ao DNA , Relação Dose-Resposta a Droga , Compostos Ferrosos/farmacologia , Humanos , Peróxido de Hidrogênio/farmacologia , Células Jurkat , Leucócitos Mononucleares/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/análise , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Glycine max , Linfócitos T/metabolismo
2.
Eur J Clin Nutr ; 58(10): 1350-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15054415

RESUMO

OBJECTIVE: This study seeks to verify whether the regular consumption of small amounts of tomato products can protect lymphocyte DNA and lipids from oxidative damage. DESIGN: Standardized dietary intervention. SUBJECTS: Twelve healthy female subjects (mean age 25.2 y). INTERVENTION: Subjects were instructed to follow a standardized diet for 1 week, followed by 3 weeks consumption of the same diet enriched with small amounts of different tomato products providing as a mean 8 mg lycopene, 0.5 mg beta-carotene and 11 mg vitamin C per day. Plasma and lymphocyte concentrations of carotenoids, vitamin C and vitamin E were analysed. Ex vivo protection of lymphocyte DNA from oxidative injury produced by iron ions was evaluated by means of the Comet assay, and lipid peroxidation by HPLC analysis of malondialdehyde (MDA). RESULTS: Dietary intervention with tomato products increased lycopene concentration both in plasma (P < 0.001) and lymphocytes (P < 0.01). Vitamin C concentrations increased by approximately 35% in plasma (P < 0.05) and by approximately 230% in lymphocytes (P < 0.005). Vitamin E decreased significantly in plasma (P < 0.0001) but not in lymphocytes. Finally, there was an improved protection from DNA oxidative damage (P < 0.05) with no significant effect on MDA levels. CONCLUSIONS: Our results suggest that tomato products are not only good sources of lycopene but also sources of bioavailable vitamin C. A Regular intake of small amounts of tomato products can increase cell protection from DNA damage induced by oxidant species. This effect may originate from the synergism of different antioxidants present in tomatoes.


Assuntos
Antioxidantes/análise , Ácido Ascórbico/sangue , Carotenoides/sangue , Linfócitos/química , Solanum lycopersicum/química , Administração Oral , Adulto , Antioxidantes/administração & dosagem , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/farmacocinética , Disponibilidade Biológica , Carotenoides/administração & dosagem , Cromatografia Líquida de Alta Pressão , Dano ao DNA/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Licopeno , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Vitamina E/análise , Vitamina E/sangue , beta Caroteno/administração & dosagem , beta Caroteno/sangue
3.
Arch Biochem Biophys ; 416(2): 196-201, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12893297

RESUMO

The purpose of this study was to investigate the protective effect of black tea (BT) extract against induced oxidative damage in Jurkat T-cell line. Cells supplemented with 10 or 25 mg/L BT were subjected to oxidation with ferrous ions. Malondialdehyde (MDA) production as marker of lipid peroxidation, DNA single strand breaks as marker of DNA damage, and modification of the antioxidant enzyme activity, glutathione peroxidase (GPX) were measured. Results show the efficacy of BT polyphenols to decrease DNA oxidative damage and to affect GPX activity (P<0.05), while no effect was shown on MDA production. The succeeding investigation of the activity of caffeine and epigallocatechin gallate demonstrated their antioxidant potential with respect to the cellular markers evaluated. In conclusion, this study supports the protective effect of BT against ferrous ions induced oxidative damage to DNA and the ability of BT to affect the enzyme antioxidant system of Jurkat cells.


Assuntos
Dano ao DNA/efeitos dos fármacos , Células Jurkat/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Chá/química , Antioxidantes/farmacologia , Camellia sinensis/química , Ativação Enzimática/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Humanos , Células Jurkat/efeitos dos fármacos , Malondialdeído/metabolismo , Oxirredução , Estresse Oxidativo/fisiologia , Fitoterapia , Extratos Vegetais/classificação
4.
J Surg Oncol ; 75(1): 55-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11025463

RESUMO

BACKGROUND AND OBJECTIVES: Primary Diffuse Malignant Peritoneal Mesothelioma is a rare disease, with an incidence of 2.2 cases in 1. 000.000 in the USA. It occupies 10% of all mesotheliomas referred in literature. METHODS: We describe a case of diffuse malignant peritoneal mesothelioma arising in a 54-year-old woman who presented a small bowel occlusion. A middle line laparotomy was done; multiple biopsies and an ileostomy were performed. There was not a history of exposure to asbestos. Histologic diagnosis was based on light microscopy, histochemistry, and immunohistochemistry. RESULTS: Patient had no further treatment because of her poor general conditions. She died 4 months later. CONCLUSIONS: Update of treatment is briefly described with particular attention to multimodality approach (surgery, chemotherapy, radiotherapy) and other new therapeutic options (iperthermochemotherapy, immunotherapy, gene therapy), currently in clinical trials.


Assuntos
Mesotelioma , Neoplasias Peritoneais , Feminino , Humanos , Ileostomia , Laparotomia , Mesotelioma/diagnóstico , Mesotelioma/patologia , Mesotelioma/cirurgia , Pessoa de Meia-Idade , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/cirurgia
5.
J Nutr ; 129(12): 2130-4, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10573539

RESUMO

Regular tea consumption has been associated with a reduced risk of cancer. As demonstrated in vitro, green tea contains catechins with antioxidant properties. We evaluated the effect of the supplementation of the Jurkat T-cell line with green tea extract on oxidative damage. Cells grown in medium with or without green tea extract (10 mg/L) were treated with Fe(2+) (100 micromol/L) as an oxidative stimulus for 2 h. Cell membrane lipid peroxidation was evaluated by fatty acids pattern analysis and malondialdehyde production in alpha-linolenic acid-loaded cells. Furthermore, oxidative DNA damage (single strand breaks) was detected in cells by the Comet assay and quantified as relative tail moment (RTM). Supplementation with green tea extract significantly decreased malondialdehyde production (1.6 +/- 0.3 vs. 0.6 +/- 0.1 nmol/mg protein, P < 0.05) and DNA damage (0.32 +/- 0.07 vs. 0.12 +/- 0.04 RTM, P < 0.05) after Fe(2+) oxidative treatment. In control cells, there was no effect on membrane distribution of (n-3) fatty acids due to Fe(2+) treatment. Cell enrichment with alpha-linolenic acid increased total membrane (n-3) fatty acids. However, the oxidative treatment did not modify the distribution of polyunsaturated fatty acids. It is likely that the observed protective effects can be attributed to epigallocatechin gallate, which is present mainly (670 g/kg) in green tea extract; however, we cannot exclude contributions by other catechins. These data support a protective effect of green tea against oxidative damage.


Assuntos
Ferro/efeitos adversos , Células Jurkat/efeitos dos fármacos , Células Jurkat/patologia , Estresse Oxidativo/fisiologia , Extratos Vegetais/farmacologia , Chá/química , Dano ao DNA/efeitos dos fármacos , Ácidos Graxos/metabolismo , Ácidos Graxos Insaturados/metabolismo , Humanos , Ferro/farmacologia , Células Jurkat/metabolismo , Malondialdeído/metabolismo
6.
Am J Surg ; 135(5): 724-5, 1978 May.
Artigo em Inglês | MEDLINE | ID: mdl-646051

RESUMO

A technic for reconstruction of the internal carotid artery after resection of carotid aneurysms is presented. Reconstruction is performed over an internal shunt using a vein or Dacron patch. Total interruption of cerebral circulation is usually less than three minutes. The technic is described in detail. Oculoplethysmographic and phonoangiographic follow-up studies demonstrate normal carotid flow.


Assuntos
Aneurisma/cirurgia , Artéria Carótida Interna/cirurgia , Prótese Vascular , Humanos , Métodos
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