Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Arch Inst Pasteur Tunis ; 88(1-4): 59-66, 2011.
Artigo em Francês | MEDLINE | ID: mdl-23461144

RESUMO

Aluminium and indium are two elements used in industrial and medical fields. The purpose of this work was to study the subcellular localization of these elements, after their single and simultaneous oral administration to rats. 2h after the administration of these two elements, the small intestine and the liver were removed.Ultrastructural study showed the presence of electron dense deposits in the lysosomes of apical parts of duodenal enterocytes. When the minerals were administered simultaneously, deposits were observed in lysosomes of duodenal and jejunal enterocytes. No deposits were seen in the hepatic tissue of treated and control rats. Microanalysis identification showed that the deposits are constituted of aluminium, indium as well as phosphorus. Our results suggested that the elements are concentrated, in lysosomes, under the form of insoluble phosphate salts and it seemed that there are no specific lysosomes for the concentration of minerals since the two elements were concentrated in the same lysosome when they are administered simultaneously.


Assuntos
Alumínio/farmacocinética , Índio/farmacocinética , Mucosa Intestinal/metabolismo , Fígado/metabolismo , Administração Oral , Alumínio/administração & dosagem , Animais , Índio/administração & dosagem , Masculino , Ratos , Ratos Wistar , Distribuição Tecidual
2.
Cell Mol Biol (Noisy-le-grand) ; 51 Suppl: OL819-27, 2005 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-16375818

RESUMO

Intragastric administration to rats of four soluble lanthanides cerium, lanthanum, europium, thulium and of three soluble elements of group IIIA aluminium, indium and gallium has been shown in previous studies. In this work two new rare earths gadolinium and terbium were studied using the same protocols and the same methods (transmission electron microscopy and ion microanalysis). among the previously studied elements, some of them were administered simultaneously on the one hand aluminium and indium, and on the other hand, lanthanum and cerium. These metals were looked for in intestinal mucosa, liver and kidney. The results showed: a) gadolinium and terbium were selectively concentrated in lysosomes of duodenal enterocytes, precipitated as non-soluble phosphate salts and eliminated with the cell's turn-over in less than 48 hr; b) Administered simultaneously, they precipitated in the same lysosome. c/ none of them was observed in the liver or kidney even with high dose. This study brings up to nine the number of elements forming a non-soluble phosphate salts, explaining their precipitation in lysosomes. None of them have a physiological role, two are toxic (aluminium and indium). This rapid intralysosomal concentration is an efficient mechanism which limits the diffusion of the foreign substances through the digestive barrier, then permits their elimination along with the cytoptose phenomenon in the intestinal lumen.


Assuntos
Enterócitos/citologia , Enterócitos/metabolismo , Elementos da Série dos Lantanídeos/administração & dosagem , Elementos da Série dos Lantanídeos/farmacocinética , Lisossomos/metabolismo , Animais , Transporte Biológico , Precipitação Química , Duodeno/ultraestrutura , Microanálise por Sonda Eletrônica , Enterócitos/ultraestrutura , Jejuno/ultraestrutura , Lisossomos/ultraestrutura , Masculino , Microvilosidades/ultraestrutura , Modelos Biológicos , Fagossomos/ultraestrutura , Ratos , Ratos Wistar , Espectrometria de Massa de Íon Secundário
3.
Arch Inst Pasteur Tunis ; 82(1-4): 59-67, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16929756

RESUMO

The subcellular localization of cerium and lanthanum in the intestinal mucosa was studied after oral administration of cerium chloride or lanthanum chloride or lanthanum chloride followed 30 minutes after of cerium chloride to young adults Wistar rats. Two methods of observation and microanalysis were used. The transmission electron microscopy revealed the presence of dense electron granulations in the lysosmes of the duodenum enterocyte, when these elements were administrated simultaneously. The ion mass microanalysis permits to detect the presence of La and Ce as bright points outlining the intestinal villi. These points correspond to the lysosomes containing the granulations previously described. These granulations are formed by the cerium and the lanthanum associated to the phosphor and forming probably insoluble salts of Ce/La phosphate.


Assuntos
Cério/administração & dosagem , Duodeno/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Lantânio/administração & dosagem , Administração Oral , Animais , Cério/análise , Cério/farmacocinética , Avaliação Pré-Clínica de Medicamentos , Duodeno/química , Duodeno/ultraestrutura , Microanálise por Sonda Eletrônica , Enterócitos/química , Enterócitos/efeitos dos fármacos , Enterócitos/ultraestrutura , Tecido de Granulação/química , Tecido de Granulação/efeitos dos fármacos , Tecido de Granulação/ultraestrutura , Absorção Intestinal , Mucosa Intestinal/química , Mucosa Intestinal/ultraestrutura , Lantânio/análise , Lantânio/farmacocinética , Lisossomos/química , Lisossomos/efeitos dos fármacos , Lisossomos/ultraestrutura , Microscopia Eletrônica de Transmissão e Varredura , Ratos , Ratos Wistar , Soluções , Fatores de Tempo
4.
Cell Mol Biol (Noisy-le-grand) ; 40(4): 483-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7914784

RESUMO

Gold injected under the form of anti-rheumatoid polyarthritis soluble solutions provokes, as observed by electron microscope, a deposit of crystalline micro-needles in different tissues, like in cells of adrenal and suprarenal glands, in Leydig cells of the testicles, in isolated thyrocytes and in thyroid endothelial cells. They are present as bundles, often of incurvated type, of high electron-density, present in lysosomes, which contain moreover a hyaline, emptied vesicle. These structures are named "aurosomes". The microanalysis, using the MS 46 (Cameca) and the Camebax (MBX) demonstrates that these crystalline structures are composed by gold associated with sulphur, and not with phosphate.


Assuntos
Antirreumáticos/farmacocinética , Dimercaprol/análogos & derivados , Ouro/análise , Compostos Organometálicos/farmacocinética , Testículo/química , Glândula Tireoide/química , Animais , Dimercaprol/farmacocinética , Microanálise por Sonda Eletrônica , Masculino , Compostos Organoáuricos , Propanóis , Ratos , Compostos de Sulfidrila , Testículo/ultraestrutura , Glândula Tireoide/ultraestrutura
5.
Ann Urol (Paris) ; 23(3): 183-7, 1989.
Artigo em Francês | MEDLINE | ID: mdl-2742347

RESUMO

Growth mechanisms of urinary calculi were studied using a scanning electron microscope (SEM) and an x-ray microanalyser (WDS). The observations obtained by SEM and x-ray mapping suggest with calcium, phosphorus, magnesium, sulfur and potassium a possible schema of growth mechanisms for urinary calculi.


Assuntos
Microanálise por Sonda Eletrônica , Cálculos Urinários/ultraestrutura , Cálcio/análise , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Fósforo/análise , Enxofre/análise , Cálculos Urinários/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...