Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Más filtros











Intervalo de año de publicación
1.
Acta Cir Bras ; 27(9): 606-10, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22936084

RESUMEN

PURPOSE: Since Technetium-99m ((99m)Tc) has favorable physical and chemical characteristics, it is widely used radioisotope in Nuclear Medicine. However, stannous dichloride (SnCl(2)) has been widely used as a reducing agent in labeling procedure of pharmaceutical with radionuclide, it has been realized that SnCl(2) have genotoxic and cytotoxic effects on biological systems. In previous studies, it has been shown that some herbal extract can reduce genotoxic and cytotoxic effects of SnCl(2). In the present study, it is aimed to evaluate the effect of the broccoli extract on the survival of E. coli ATCC 25922 strain against to toxic effects of SnCl(2). METHODS: Broccoli was extracted with methanol extraction. HPLC and TLC analysis of broccoli extract were performed. Then antitoxicity and dose response assays were performed on bacterial strain. RESULTS: The broccoli extract had dose dependent protective effect against SnCl(2) toxic effect on E. coli. CONCLUSIONS: The consumption of broccoli may alter the stannous dichloride toxicity. Broccoli extract may use as a new protective strategies against the toxic effect of SnCl(2) on patients who were taken (99m)Tc radiopharmaceuticals.


Asunto(s)
Brassica/química , Escherichia coli/efectos de los fármacos , Extractos Vegetales/farmacología , Radiofármacos/toxicidad , Tecnecio/toxicidad , Compuestos de Estaño/toxicidad , Cromatografía en Capa Delgada , Radiofármacos/antagonistas & inhibidores , Compuestos de Estaño/antagonistas & inhibidores
2.
Acta cir. bras ; 27(9): 606-610, Sept. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-646725

RESUMEN

PURPOSE: Since Technetium-99m (99mTc) has favorable physical and chemical characteristics, it is widely used radioisotope in Nuclear Medicine. However, stannous dichloride (SnCl2) has been widely used as a reducing agent in labeling procedure of pharmaceutical with radionuclide, it has been realized that SnCl2 have genotoxic and cytotoxic effects on biological systems. In previous studies, it has been shown that some herbal extract can reduce genotoxic and cytotoxic effects of SnCl2. In the present study, it is aimed to evaluate the effect of the broccoli extract on the survival of E. coli ATCC 25922 strain against to toxic effects of SnCl2. METHODS: Broccoli was extracted with methanol extraction. HPLC and TLC analysis of broccoli extract were performed. Then antitoxicity and dose response assays were performed on bacterial strain. RESULTS: The broccoli extract had dose dependent protective effect against SnCl2 toxic effect on E. coli. CONCLUSIONS: The consumption of broccoli may alter the stannous dichloride toxicity. Broccoli extract may use as a new protective strategies against the toxic effect of SnCl2 on patients who were taken 99mTc radiopharmaceuticals.


OBJETIVO: Em face de suas características físico-químicas, o Tecnécio-99m (99mTc) é um radiofármaco amplamente utilizado na Medicina Nuclear. Todavia, o dicloreto de estanho (SnCl2) tem sido largamente aplicado como um agente redutor no procedimento farmacêutico de marcação com radionuclídeos. Constatou-se que o SnCl2 apresenta efeitos genotóxicos e citotóxicos nos sistemas biológicos. Em estudos prévios, foi demonstrado que alguns extratos de ervas podem reduzir tais efeitos. O estudo atual objetivou avaliar os efeitos do extrato de brócolis na sobrevida da cepa E. coli ATCC 25922, exposta ao efeito tóxico do SnCl2. MÉTODOS: O extrato de brócolis foi obtido mediante extração com metanol. Analises com HPLC e TLC foram efetuadas. Avaliou-se a antitoxicidade e realizou-se um ensaio dose-resposta para uma cepa de bactérias. RESULTADOS: O extrato de brócolis mostrou um efeito protetor dose dependente para os efeitos tóxicos do SnCl2 sobre a E. coli. CONCLUSÕES: O consumo de brócolis pode alterar a toxicidade do dicloreto de estanho. O extrato de brócolis pode ser utilizado como uma nova estratégia para proteção de pacientes contra os efeitos tóxicos do SnCl2, nos quais foi administrado o radiofármaco Tecnécio-99m.


Asunto(s)
Brassica/química , Escherichia coli/efectos de los fármacos , Extractos Vegetales/farmacología , Radiofármacos/toxicidad , Tecnecio/toxicidad , Compuestos de Estaño/toxicidad , Cromatografía en Capa Delgada , Radiofármacos/antagonistas & inhibidores , Compuestos de Estaño/antagonistas & inhibidores
3.
Bioorg Med Chem ; 20(12): 3698-702, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22608919

RESUMEN

The radiosynthesis and in vivo evaluation of 5-(5-(6-[(11)C]methyl-3,6-diazabicyclo[3.2.0]heptan-3-yl)pyridin-2-yl)-1H-indole [(11)C]rac-(1), a potential PET tracer for α7 nicotinic acetylcholine receptors (α7-nAChR), are described. Syntheses of the nonradioactive standard rac-1 and corresponding desmethyl precursor 7 were achieved in several reaction steps. Radiomethylation of 7 with [(11)C]CH(3)I afforded [(11)C]rac-1 in an average radiochemical yield of 30 ± 5% (n=5) with high radiochemical purity and an average specific radioactivity of 444 ± 74 GBq/µmol (n=5). The total synthesis time was 30 min from end-of-bombardment. Biodistribution studies in mice showed that [(11)C]rac-1 penetrates the blood-brain barrier and specifically labels neuronal α7-nAChRs.


Asunto(s)
Encéfalo/diagnóstico por imagen , Indoles , Tomografía de Emisión de Positrones , Piridinas , Radiofármacos , Receptores Nicotínicos/análisis , Animales , Encéfalo/metabolismo , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Indoles/antagonistas & inhibidores , Ligandos , Ratones , Ratones Endogámicos , Estructura Molecular , Piridinas/antagonistas & inhibidores , Quinuclidinas/farmacología , Radiofármacos/antagonistas & inhibidores , Radiofármacos/química , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7
6.
Nucl Med Biol ; 29(5): 517-25, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12088721

RESUMEN

A carbon-11 labeled methoxyl analog of CP-101,606, (+/-)threo-1-(4-hydroxyphenyl)-2-[4-hydroxy-4-(p-[11C]methoxyphenyl)piperidino]-1-propanol [(+/-)[11C]1], was synthesized as a new subtype-selective PET radioligand for NMDA receptors. The in vitro binding studies using rat brain slices demonstrated that (+/-)[11C]1 shows an extremely high-specific binding to the NR2B subunit of NMDA receptors. In contrast to the in vitro binding, the in vivo binding to mouse and monkey brains showed no apparent specific localization of the radioactivity in any of the brain regions. Metabolism and physicochemical properties such as the lipophilicity of (+/-)[11C]1 seemed unlikely to affect the in vivo (+/-)[11C]1 binding. Among the various endogenous ligands acting at the NMDA receptors, polyamines (spermine and spermidine) and divalent cations (Mg(2+,) Zn(2+,) and Ca(2+)) strongly inhibited the in vitro (+/-)[11C]1 binding. Thus, the present studies point to the possibility that the polyamines and cations behave as endogenous inhibitors for (+/-)[11C]1 binding, leading to the loss of the specific binding in vivo.


Asunto(s)
Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Radioisótopos de Carbono/farmacocinética , Piperidinas/síntesis química , Piperidinas/farmacocinética , Receptores de N-Metil-D-Aspartato/metabolismo , Animales , Encéfalo/irrigación sanguínea , Marcaje Isotópico/métodos , Macaca , Masculino , Metales/farmacología , Ratones , Piperidinas/antagonistas & inhibidores , Piperidinas/farmacología , Radiofármacos/antagonistas & inhibidores , Radiofármacos/farmacocinética , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espermina/farmacología , Distribución Tisular , Tomografía Computarizada de Emisión , Recuento Corporal Total
7.
Neuroreport ; 10(13): 2715-21, 1999 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-10511429

RESUMEN

2-[18F]fluoro-3-(2(S)-azetidinylmethoxy)pyridine (2-[18F]F-A-85380), a ligand for nicotinic acetylcholine receptors (nAChRs) was evaluated in an in vitro binding assay with membranes of rat brain and in vivo by PET in Rhesus monkey brain. The ligand has high affinity for alpha4beta2 nAChRs (K(D)=50 pM), crosses the blood-brain barrier, and distributes in the monkey brain in a pattern consistent with that of alpha4beta2 nAChRs. The specific/non-specific binding ratio increased steadily, reaching a value of 3.3 in the thalamus at 4 h. The specific binding of 2-[18F]F-A-85380 was reversed by cytisine. These results, in combination with the data demonstrating low toxicity of 2-[18F]F-A-85380, indicate that this ligand shows promise for use with PET in human subjects.


Asunto(s)
Azetidinas , Piridinas , Radiofármacos , Receptores Nicotínicos/metabolismo , Tomografía Computarizada de Emisión , Alcaloides/farmacología , Animales , Azetidinas/antagonistas & inhibidores , Azetidinas/metabolismo , Azetidinas/farmacocinética , Azocinas , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Ligandos , Macaca mulatta , Piridinas/antagonistas & inhibidores , Piridinas/metabolismo , Piridinas/farmacocinética , Quinolizinas , Radiofármacos/antagonistas & inhibidores , Radiofármacos/metabolismo , Radiofármacos/farmacocinética , Ratas , Tálamo/metabolismo , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA