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1.
Exp Toxicol Pathol ; 65(1-2): 165-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21924598

RESUMO

The hepatoprotective activity of the aqueous extract of the shells of pecan nut was investigated against ethanol-induced liver damage. This by-product of the food industry is popularly used to treat toxicological diseases. We evaluated the phytochemical properties of pecan shell aqueous extract (AE) and its in vitro and ex vivo antioxidant activity. The AE was found to have a high content of total polyphenols (192.4±1.9 mg GAE/g), condensed tannins (58.4±2.2 mg CE/g), and antioxidant capacity, and it inhibited Fe(2+)-induced lipid peroxidation (LP) in vitro. Rats chronically treated with ethanol (Et) had increased plasmatic transaminases (ALT, AST) and gamma glutamyl transpeptidase (GGT) levels (96%, 59.13% and 465.9%, respectively), which were effectively prevented (87; 41 and 383%) by the extract (1:40, w/v). In liver, ethanol consumption increased the LP (121%) and decreased such antioxidant defenses as glutathione (GSH) (33%) and superoxide dismutase (SOD) (47%) levels, causing genotoxicity in erythrocytes. Treatment with pecan shell AE prevented the development of LP (43%), GSH and SOD depletion (33% and 109%, respectively) and ethanol-induced erythrocyte genotoxicity. Catalase activity in the liver was unchanged by ethanol but was increased by the extract (47% and 73% in AE and AE+Et, respectively). Therefore, pecan shells may be an economic agent to treat liver diseases related to ethanol consumption.


Assuntos
Antioxidantes/uso terapêutico , Carya/química , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Etanol/toxicidade , Fígado/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Eritrócitos/diagnóstico por imagem , Eritrócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Testes de Função Hepática , Masculino , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Nozes/química , Picratos/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/química , Ultrassonografia
2.
Appl Radiat Isot ; 66(12): 1788-92, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18586503

RESUMO

The aim of this study was to evaluate possible effects of Passiflora edulis flavicarpa (P. flavicarpa) extract on the labeling of blood constituents with (99m)Tc, on the morphology of red blood cells, and on the biodistribution of sodium pertechnetate (sodium (99m)Tc). Male Wistar rats were treated with either P. flavicarpa extract or 0.9% NaCl. After that, radiolabeling of blood constituents, morphological analysis of red blood cells and biodistribution of sodium (99m)Tc was evaluated. Radiolabeling of blood constituents and shape of red blood cells were not modified, but a significant (p<0.05) alteration of the biodistribution of sodium (99m)Tc was observed after treatment with P. flavicarpa extract. Although our results were obtained with animals, they could contribute to reduce the risk of misdiagnosis and/or repetition of the examinations in nuclear medicine.


Assuntos
Eritrócitos/citologia , Eritrócitos/diagnóstico por imagem , Passiflora/química , Extratos Vegetais/administração & dosagem , Pertecnetato Tc 99m de Sódio/farmacocinética , Animais , Eritrócitos/efeitos dos fármacos , Marcação por Isótopo/métodos , Masculino , Taxa de Depuração Metabólica/efeitos dos fármacos , Especificidade de Órgãos/efeitos dos fármacos , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Wistar , Distribuição Tecidual/efeitos dos fármacos
3.
Perfusion ; 21(5): 291-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17201084

RESUMO

BACKGROUND: Either a roller pump or a centrifugal pump can be used in the extracorporeal circuit during surgery with cardiopulmonary bypass. In this study, we assessed the effect of these two pumps on the 24-h post-transfusion survival values of autologous red blood cells (RBC). STUDY DESIGN AND METHODS: Fourteen male patients subjected to extracorporeal bypass procedures were studied. In seven patients, the autologous red cells were collected following the cardiopulmonary bypass procedure using the roller pump, and in seven patients, autologous red cells were collected following the cardiopulmonary procedure using the centrifugal pump. The 24-h post-transfusion survival values of the autologous RBC were measured using the 51 disodium chromate/99m technetium double isotope procedure. The effects of the extracorporeal bypass procedures using the roller pump and the centrifugal pump were also assessed by the measurements of hematocrit, platelet count, plasma hemoglobin, and serum lactate dehydrogenase levels. RESULTS: The 51 disodium chromate 24-h post-transfusion survival values of the autologous RBC were similar whether the roller pump or the centrifugal pump was used in the extracorporeal circulation, as were the hematocrit, platelet count, plasma hemoglobin and serum lactate dehydrogenase levels. CONCLUSION: The 24-h post-transfusion survival values of autologous RBC, measured by the 51 disodium chromate/99m technetium double isotope procedure, were not significantly different, whether the roller pump or the centrifugal pump was used in the extracorporeal circuit using membrane oxygenators during cardiopulmonary surgical procedures.


Assuntos
Transfusão de Sangue Autóloga , Eritrócitos , Oxigenação por Membrana Extracorpórea/instrumentação , Hemólise , Adulto , Idoso , Transfusão de Sangue , Ponte Cardiopulmonar , Ponte de Artéria Coronária , Desenho de Equipamento , Volume de Eritrócitos , Eritrócitos/diagnóstico por imagem , Oxigenação por Membrana Extracorpórea/efeitos adversos , Feminino , Hematócrito , Hemoglobinas/análise , Humanos , Hipotermia Induzida , Anastomose de Artéria Torácica Interna-Coronária , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia , Compostos Radiofarmacêuticos , Tecnécio
4.
Acta Cir Bras ; 20 Suppl 1: 121-5, 2005.
Artigo em Português | MEDLINE | ID: mdl-16186979

RESUMO

PURPOSE: To evaluate the effect of a hiperico extract (Hypericum perforatum) on the labeling of blood elements with technetium-99m (99mTc) and in the bioavailability of the radiopharmaceutical sodium pertechnetate in Wistar rats. METHODS: Blood (heparinized) withdrawn from Wistar rats is incubated with a hiperico extract, with a stannous cloride and with 99mTc, as sodium pertechnetate (99mTcONa). Plasma (P) and cells (C) are isolated by centrifugation. Samples of P and C are also precipitated with trichloroacetic acid (TCA 5%) and soluble (FS-P; FS-C) and isoluble (FI-P; FI-C) fractions are separated. In the bioavailability analysis, the extract or NaCl 0.9% solution is administrated into Wistar rats (gavage) during 15 days. Sodium pertechnetate was administered and after 10 min, the animals are sacrificed, the organs were isolated, the radioactivity determined in a well counter, and the percentages of radioactivity per gram (%ATI/g) in the organs are calculated. RESULTS: The hiperico extract decreasedsignificantly (P < 0.05) the %ATI in the cells, cellular insoluble fraction and plasma insoluble fraction. The biodistribution was significantly (P < 0.01) decreased in bone, muscle and thyroid and significantly (P < 0.05) increased in pancreas. CONCLUSION: The analysis of the results indicates that in studied extract should have substances that should oxidize the stannous ion, reducing the fixation of the 99mTc on the erythrocytes and plasma and cellular proteins. Moreover, it could produce metabolic alterations with influence in the uptake of the radiopharmaceutical 99mTcO4Na in bone, muscle, pancreas and thyroid.


Assuntos
Eritrócitos/diagnóstico por imagem , Hypericum/química , Compostos Radiofarmacêuticos/farmacocinética , Pertecnetato Tc 99m de Sódio/farmacocinética , Animais , Disponibilidade Biológica , Osso e Ossos/metabolismo , Eritrócitos/metabolismo , Marcação por Isótopo , Masculino , Músculos/metabolismo , Pâncreas/metabolismo , Extratos Vegetais/farmacologia , Cintilografia , Ratos , Glândula Tireoide/metabolismo , Compostos de Estanho/sangue , Distribuição Tecidual
5.
Cancer Lett ; 222(1): 49-55, 2005 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-15837540

RESUMO

This study demonstrates that mammalian cell targets (erythrocytes and tumour cells) may be sensitised to ultrasound using electric pulses and this combination treatment results in destruction of those cells in vitro. It further demonstrates that when a tumour mass is treated in vivo using combined electric field and ultrasound therapy, significant retardation of tumour growth has been observed using a mouse tumour model. We suggest that combined electric field and ultrasound (CEFUS) therapy may provide a novel, drug-free treatment modality for cancer.


Assuntos
Terapia por Estimulação Elétrica , Eritrócitos/diagnóstico por imagem , Neoplasias/terapia , Terapia por Ultrassom , Animais , Linhagem Celular Tumoral , Terapia Combinada , Modelos Animais de Doenças , Humanos , Camundongos , Ultrassonografia
6.
Braz J Med Biol Res ; 37(2): 267-71, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14762583

RESUMO

Ginkgo biloba extract (EGb) is a phytotherapeutic agent used for the treatment of ischemic and neurological disorders. Because the action of this important extract is not fully known, assays using different biological systems need to be performed. Red blood cells (RBC) are labeled with technetium-99m (Tc-99m) and used in nuclear medicine. The labeling depends on a reducing agent, usually stannous chloride (SnCl2). We assessed the effect of different concentrations of EGb on the labeling of blood constituents with Tc-99m, as sodium pertechnetate (3.7 MBq), and on the mobility of a plasmid DNA treated with SnCl2 (1.2 microg/ml) at room temperature. Blood was incubated with EGb before the addition of SnCl2 and Tc-99m. Plasma (P) and RBC were separated and precipitated with trichloroacetic acid, and soluble (SF-P and SF-RBC) and insoluble (IF-P and IF-RBC) fractions were isolated. The plasmid was incubated with Egb, SnCl2 or EGb plus SnCl2 and agarose gel electrophoresis was performed. The gel was stained with ethidium bromide and the DNA bands were visualized by fluorescence in an ultraviolet transilluminator system. EGb decreased the labeling of RBC, IF-P and IF-RBC. The supercoiled form of the plasmid was modified by treatment with SnCl2 and protected by 40 mg/ml EGb. The effect of EGb on the tested systems may be due to its chelating action with the stannous ions and/or pertechnetate or to the capability to generate reactive oxygen species that could oxidize the stannous ion.


Assuntos
DNA/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Ginkgo biloba , Plasmídeos/efeitos dos fármacos , Compostos de Estanho/farmacologia , Animais , Proteínas Sanguíneas/efeitos dos fármacos , Eletroforese em Gel de Ágar , Eritrócitos/diagnóstico por imagem , Humanos , Marcação por Isótopo , Extratos Vegetais/farmacologia , Cintilografia , Pertecnetato Tc 99m de Sódio/sangue , Pertecnetato Tc 99m de Sódio/farmacologia , Tecnécio/sangue , Tecnécio/farmacologia
7.
Ultrasound Med Biol ; 29(1): 103-12, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12604121

RESUMO

This project tested the hypothesis that human erythrocytes pretreated with Trolox (a water-soluble analog of vitamin E) would be more susceptible to ultrasound (US)-induced hemolysis by a cavitational mechanism because of an increased fragility of the erythrocyte membrane over that without Trolox supplementation. Samples of whole human blood from apparently healthy donors (hematocrit approximately 40%) in vitro were supplemented or not supplemented with Trolox at various concentrations, ranging from 1.8 to 0.0018 mg/mL plasma. Mechanical fragility tests indicated the Trolox-treated blood in vitro exhibited greater hemolysis than untreated blood in vitro (p < 0.001). US exposures at comparable acoustic amplitude, pulse length and duty factor in the presence of the US contrast agent Albunex yielded differing results; at 1 MHz, the Trolox-supplemented blood had significantly greater hemolysis in vitro than non-Trolox-supplemented blood; at 3 MHz, there was a substantial reduction in hemolysis relative to that obtained at 1 MHz, and no statistically significant difference between the Trolox-supplemented and -unsupplemented blood. There was also essentially no support for an alternative hypothesis that the Trolox was functioning primarily as a pro-oxidant. These collective experimental results support the hypothesis and suggest duality in the functionality of membranous antioxidant inclusions or associations; they may foster protection against oxidative damage, yet render the cell less capable of withstanding mechanical stress.


Assuntos
Antioxidantes/farmacologia , Cromanos/farmacologia , Eritrócitos , Hemólise/efeitos dos fármacos , Ultrassonografia , Membrana Eritrocítica/fisiologia , Eritrócitos/diagnóstico por imagem , Humanos , Técnicas In Vitro , Fragilidade Osmótica
8.
Cell Mol Biol (Noisy-le-grand) ; 48(7): 751-5, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12619970

RESUMO

Sechium edule (chayotte) is used as food or as medication in popular medicine. The labeling of blood elements with technetium-99m (99mTc) has been altered by drugs (synthetic and natural). Some authors have reported biological effects concerning the chayotte. We have evaluated the influence of chayotte extracts (macerated and infusion) on the labeling of blood elements with 99mTc. In vitro study, blood was incubated with the extracts, (6.25, 12.5, 25, 50 and 100% v/v). In in vivo study, the animals were treated with the extracts (100% v/v), as drinking water (15 and 60 days) and samples of blood were withdrawn. The blood samples were incubated with stannous chloride and with 99mTc. Plasma (P) and blood cells (BC) were isolated, also precipitated with trichloroacetic acid and soluble (SF) and insoluble fractions (IF) separated. There was a (p < 0.05) decrease in the radioactivity in BC, IF-BC and IF-P with the infusion (100%) and a slight decrease in the uptake of 99mTc by BC and a strong decrease in the fixation in IF-P with the macerated when the extracts were administrated in vivo (15 days). In 60 days, there was a decrease in BC (98.77 to 53.53%), in IF-BC (90.36 to 21.20%) and in IF-P (77.20 to 11.01%). In vitro study no alterations on the labeling of blood elements were found, however, we have found alterations on the fixation of 99mTc in the in vivo study, probably, due to the metabolization of chayotte capable to induce the generation of active metabolites.


Assuntos
Proteínas Sanguíneas/metabolismo , Cucurbitaceae/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/diagnóstico por imagem , Tecnécio/sangue , Animais , Eritrócitos/metabolismo , Técnicas In Vitro , Extratos Vegetais/farmacologia , Cintilografia , Compostos Radiofarmacêuticos/sangue , Ratos , Ratos Wistar , Solubilidade
9.
Cell Mol Biol (Noisy-le-grand) ; 48(7): 771-6, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12619974

RESUMO

The use of eggplant has been suggested to treat different diseases. We studied the effect of eggplant extract on the labeling of red blood cells (RBC) and plasma proteins with technetium-99m (Tc-99m) and on biodistribution of sodium pertechnetate (Tc-99m) in rats. Blood was incubated with an eggplant extract (final concentrations 3.12 to 250.00 mg/ml) for 60 min. Then, stannous chloride (SnCl2) (0.06 or 1.2 microg/ml) and Tc-99m, as sodium pertechnetate, were added. Samples of RBC and plasma (P) were separated and also precipitated and soluble (SF) and insoluble (IF) fractions were isolated. The percent of radioactivity (%ATI) in the fractions was calculated. In the biodistribution study, Wistar rats were treated with eggplant extract (300 mg/ml) for 4 weeks, in drinking water. Tc-99m was administered in the rats, after 90 min they were sacrificed and organs and blood were isolated. When 0.06 microg/ml SnCl2 was used, eggplant extract: i/ inhibited the label of RBC (97.14 +/- 2.01 to 52.21 +/- 3.97%ATI), ii/ decreased the labeling in IF-P from 38.79 +/- 11.73 to 5.49 +/- 2.65%ATI, and iii/ diminished the labeling in IF-RBC from 90.04 +/- 2.65 to 46.17 +/- 9.49%ATI. This inhibitory effect was not observed with SnCl2 1.2 microg/ml. In the biodistribution study, the %ATI: i/ increased in the liver from 2.15 +/- 0.54 to 3.11 +/- 1.29 and ii/ in the other organs the Tc-99m uptake was not modified. The uptake of Tc-99m in red blood cells protein (IF-RBC) decreased from 66.62 +/- 19.67 to 31.66 +/- 8.84%. It is possible to suggest that some components of the eggplant extract present an oxidation power able to alter the fixation of the Tc-99m on the blood elements. Moreover, as eggplant is metabolized in the liver, this fact could justify the alteration of the uptake in this organ.


Assuntos
Compostos Radiofarmacêuticos/sangue , Compostos Radiofarmacêuticos/farmacocinética , Pertecnetato Tc 99m de Sódio/sangue , Pertecnetato Tc 99m de Sódio/farmacocinética , Solanum melongena/química , Animais , Proteínas Sanguíneas/metabolismo , Eritrócitos/diagnóstico por imagem , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Técnicas In Vitro , Extratos Vegetais/farmacologia , Cintilografia , Ratos , Ratos Wistar , Distribuição Tecidual
10.
Curr Pharm Des ; 6(11): 1179-91, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10903389

RESUMO

The influence of drugs on the labeling of red blood cells and plasma proteins with 99mTc has been reported. Any drug, which alters the labeling of the tracer, could be expected to modify the disposition of the radiopharmaceuticals. Red blood cells (RBC) labeled with technetium-99m (99mTc) are used for several evaluations in nuclear medicine. We have evaluated the effect of Thuya occidentalis, Peumus boldus and Nicotiana tabacum (tobacco) extracts on the labeling of RBC and plasma and cellular proteins with 99mTc. Blood was incubated with the drugs. Stannous chloride (SnCl2) solutions and 99mTc were added. Plasma (P) and blood cells (BC) were separated. The percentage of radioactivity (%ATI) bound to P and BC was determined. The %ATI on the plasma and cellular proteins was also evaluated by precipitation of P and BC samples with trichloroacetic acid (TCA) and isolation of soluble (SF) and insoluble (IF) fractions. The analysis of the results shows that there is a decrease in %ATI (from 97.64 to 75.89 percent) in BC with Thuya occidentalis extract. The labeling of RBC and plasma proteins can be decreased in presence of tobacco. This can be due either a direct or indirect effect (reactive oxygen species) of tobacco. The analysis of radioactivity in samples of P and BC isolated from samples of whole blood treated with Peumus boldus showed a rapid uptake of the radioactivity by blood cells in the presence of the Peumus boldus, whereas there was a slight decrease in the amount of 99mTc radioactivity in the TCA-insoluble fraction of plasma. This study shows that extracts of some medicinal plants can affect the radiolabeling of red blood cells with 99mTc using an in vitro technique.


Assuntos
Eritrócitos/diagnóstico por imagem , Extratos Vegetais/farmacologia , Tecnécio/sangue , Animais , Proteínas Sanguíneas/metabolismo , Eritrócitos/metabolismo , Marcação por Isótopo , Extratos Vegetais/farmacocinética , Plantas Medicinais/química , Plantas Tóxicas , Ligação Proteica , Cintilografia , Ratos , Ratos Wistar , Compostos de Estanho/sangue , Nicotiana/química
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