Base de dados : LILACS
Pesquisa : D08.811.277.040.025.095 [Categoria DeCS]
Referências encontradas : 16 [refinar]
Mostrando: 1 .. 10   no formato [Detalhado]

página 1 de 2 ir para página        

  1 / 16 LILACS  
              next record last record
seleciona
para imprimir
Fotocópia
Id: lil-335885
Autor: Biscardi, Ana M; Lopez, Lida M; Pahn, Esther M; Iraldi, Amanda Pellegrino de; Stoppani, Andrés O. M.
Título: Effect of dyskinetoplastic agents on ultrastructure and oxidative phosphorylation in Crithidia fasciculata
Fonte: Biocell;25(1):43-51, Apr. 2001.
Idioma: en.
Resumo: Ethidium bromide (EB) is an intercalating agent which binds specifically to the kinetoplast (mitochondrial) DNA (kDNA) of trypanosomatids. Accordingly, EB inhibits DNA replication, thus inducing dyskinetoplasty. Since in eukariotic organisms mitochondrial DNA encodes the genetic information for cytochromes b, aa3 and F0F1 ATPase, it seemed of interest to establish whether a similar effect occurs in Crithidia fasciculata, a trypanosomatid used for assay of potential trypanocidal drugs. Culturing of C. fasciculata in the presence of EB inhibited growth and induced dyskinetoplasty, as confirmed by electron microscopy. The kinetoplast of EB-cultured crithidia lost its characteristic arc shape, it was misplaced in the cell cytoplasm its matrix structure and membrane differentiation were specifically modified. Dyskinetoplasty decreased crithidia respiration and oxidative phosphorylation, as indicated by the lower ATP level, ATP/ADP ratio and adenylate energy charge. The interference of EB with kinetoplastic constituents synthesis was confirmed by the lack of action of EB on crithidia in the stationary phase of growth, that ruled out direct inhibition of oxidative phosphorylation enzymes. The lipophilic o-naphthoquinone beta-lapachone produced structural alterations in kinetoplast membranes, that correlated with inhibition of oxidative phosphorylation. These latter effects involved free radicals since they were prevented by free radical scavengers.
Descritores: Crithidia fasciculata
DNA de Cinetoplasto
Etídio
Fosforilação Oxidativa/efeitos dos fármacos
Mitocôndrias
Tripanossomicidas
-Trifosfato de Adenosina
ATPase de Ca(2+) e Mg(2+)
Crithidia fasciculata
DNA de Cinetoplasto
Mitocôndrias
Naftoquinonas
Compostos de Sulfidrila
Limites: Animais
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  2 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo SciELO Brasil
Texto completo
Id: lil-295884
Autor: Noël, F; Cunha, V. M. N; Silva, C. L. M; Mendonça-Silva, D. L.
Título: Control of calcium homeostasis in Schistosoma mansoni
Fonte: Mem. Inst. Oswaldo Cruz;96(suppl):85-88, Sept. 2001. ilus, tab.
Idioma: en.
Resumo: Calcium signalling is fundamental for muscular contractility of Schistosoma mansoni. We have previously described the presence of transport ATPases (Na+,K+-ATPase and (Ca2+-Mg2+)-ATPase) and calcium channels (ryanodine receptors - RyR) involved in control of calcium homeostasis in this worm. Here we briefly review the main technics (ATPase activity, binding with specific radioligands, fluxes of 45Ca2+ and whole worm contractions) and results obtained in order to compare the distribution patterns of these proteins: thapsigargin-sensitive (Ca2+-Mg2+)-ATPase activity and RyR co-purified in P1 and P4 fractions mainly, which is compatible with a sarcoplasmic reticulum localization, while basal ATPase (along with Na+,K+-ATPase) and thapsigargin-resistant (Ca2+-Mg2+)-ATPase have a distinct distribution, indicative of their plasma membrane localization. Finally we attempt to integrate these contributions with data from other groups in order to propose the first synoptic model for control of calcium homeostasis in S. mansoni
Descritores: Cálcio/fisiologia
Homeostase/fisiologia
Schistosoma mansoni/metabolismo
-ATPase de Ca(2+) e Mg(2+)/metabolismo
Sinalização do Cálcio
Cálcio/metabolismo
Músculo Liso/metabolismo
Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo
ATPase Trocadora de Sódio-Potássio/metabolismo
Limites: Animais
Tipo de Publ: Research Support, U.S. Gov't, P.H.S.
Responsável: BR1.1 - BIREME


  3 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-229468
Autor: Durán, Nelson; Justo, Giselle Zenker; Haun, Marcela; Souza-Brito, Alba Regina Monteiro.
Título: O magnésio e o sistema biológico / Magnesium and the biological system
Fonte: Rev. ciênc. farm;19(1):9-36, 1998.
Idioma: pt.
Resumo: Desde que o magnésio foi introduzido na terapia há aproximadamente 30 anos, inúmeros estudos clínicos deveriam ter sido feitos. Embora um grande número de resultados experimentais tem demonstrado a importância do magnésio em eventos biológicos, o interesse pela terapia com magnésio ainda caminha a passos lentos, podendo ser atribuído principalmente às restriçöes dirigidas à prevençäo de doenças, particularmente aquelas associadas ao sistema imune. Entretanto, as aplicaçöes promissoras da terapia com magnésio vêm progredindo à luz da dedicaçäo de grupos de pesquisa de excelência, fazendo que a significância do magnésio näo seja ignorada. O propósito deste trabalho é o de resumir alguns aspectos relevantes da importância biológica deste cátion, com especial atençäo ao seu papel nos mecanismos de resistência e imunocompetência.
Descritores: Trifosfato de Adenosina/metabolismo
ATPase de Ca(2+) e Mg(2+)/metabolismo
Histamina
Sistema Imunitário/fisiologia
Imunocompetência
Imunoglobulinas
Magnésio/farmacocinética
Magnésio/fisiologia
Potássio
Sódio/sangue
-Formação de Anticorpos
Linfócitos B/metabolismo
Sítios de Ligação
Ativação do Complemento
Granulócitos
Imunidade Celular
Deficiência de Magnésio
Substância P
Linfócitos T/metabolismo
Limites: Humanos
Animais
Tipo de Publ: Revisão
Responsável: BR33.1 - Divisão Técnica de Biblioteca e Documentação


  4 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-228622
Autor: Docampo, Roberto.
Título: Calcium homeostasis in Trypanosoma cruzi
Fonte: Biol. Res;26(1/2):189-96, 1993.
Idioma: en.
Resumo: By using the fluorescent Ca2+ indicator fura 2, submicromolar levels of intracellular Ca2+ have been detected in Trypanosoma cruzi different stages. The intracellular transport mechanisms involved in maintaining Ca2+ homeostasis in T. cruzi have been characterized by measuring Ca2+ transport in digitonin-permeabilized cells. Two intracellular calcium transport systems have been detected. Ca2+ uptake by the mitochondria occurs by an electrophoretic mechanism, is inhibited by antimycin A, FCCP, and ruthenium red, and stimulated by respiratory substrates, phosphate and acetate. This pool has a high capacity and low affinity for Ca2+ and is able to buffer external Ca2+ at concentrations in the range of 0.6-0.7 microM. Ca2+ uptake by the endoplasmic reticulum is inhibited by high concentrations of vanadate and anticalmodulin agents, and stimulated by ATP. This pool has a low capacity and a high affinity for Ca2+ and is able to buffer external Ca2+ at concentrations in the range of 0.05-1.0 microM. In addition, calmodulin has been purified from T. cruzi epimastigotes and shown to stimulate the homologous plasma membrane Ca(2+)-ATPase and cyclic-AMP phosphodiesterase. The gene encoding this protein has been cloned and sequenced and shown to have a great homology to mammalian calmodulin. The role of the plasma membrane of T. cruzi in the regulation of [Ca2+]i has been studied using fura 2-loaded epimastigotes or plasma membrane vesicles prepared from epimastigotes. Plasma membrane vesicles transport Ca2+ in the presence of Mg2+ and have a high affinity, vanadate-sensitive (Ca(2+)-Mg2+)-ATPase with an apparent Km for free Ca2+ of 0.3 microM.(ABSTRACT TRUNCATED AT 250 WORDS)
Descritores: Cálcio/metabolismo
Homeostase
Trypanosoma cruzi/metabolismo
-Antimicina A/farmacologia
Transporte Biológico
ATPase de Ca(2+) e Mg(2+)/efeitos dos fármacos
ATPase de Ca(2+) e Mg(2+)/metabolismo
Calmodulina/antagonistas & inibidores
Calmodulina/metabolismo
Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia
Permeabilidade da Membrana Celular/efeitos dos fármacos
Membrana Celular/efeitos dos fármacos
Membrana Celular/metabolismo
Digitonina/farmacologia
Fura-2
Homeostase/efeitos dos fármacos
Imidazóis/farmacologia
Membranas Intracelulares/efeitos dos fármacos
Membranas Intracelulares/metabolismo
Potenciais da Membrana/efeitos dos fármacos
Mitocôndrias/efeitos dos fármacos
Rutênio Vermelho/farmacologia
Trifluoperazina/farmacologia
Trypanosoma cruzi/efeitos dos fármacos
Vanadatos/farmacologia
Limites: Animais
Tipo de Publ: Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S.
Responsável: BR1.1 - BIREME


  5 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-228577
Autor: Koenig, Cecilia S; Dabike, Monica; Nuñez, Rebeca; Munizaga, Alejandro; Brandan, Enrique; Garrido, Jorge.
Título: Differentiation of oxyntic cells and cell-matrix interactions during avian gastric gland morphogenesis
Fonte: Biol. Res;27(3/4):177-92, 1994. ilus, graf.
Idioma: en.
Resumo: The relation between the expression of the oxyntic cell phenotype and the modifications of the extracellular matrix during development of the gastric glands, was studied in 10 to 21 day-old chick embryos. Cytodifferentiation of the oxyntic cells was established by ultrastructural methods, while the expression of pepsinogen, mitochondrial enzyme markers and apical secretory membranes was determined by histochemical and biochemical procedures. Results show that the morphogenesis of the glandular lobules occurs between days 8 and 15 of gestation. Later on, the lobules enlarge but maintain their basic morphology. Until day 13, the developing glands consist of primary tubes lined by a stratified columnar epithelium. The apical poles of the cells that contact the lumen show cytoplasmic processes, and Mg-ATPase activity and F-actin are concentrated at the apical cell borders. From day 13 on, the cells of the simple epithelium that lines secondary tubules budding from the primary tube, show all the features that define differentiated oxyntic cells. The synthesis of glycosaminoglycans during glandular morphogenesis was studied measuring the incorporation of radioactive sulfate into developing chick embryo proventriculi. An important increase in isotope incorporation was found between days 13 and 18 of development. Histochemical localization of these macromolecules shows that glycosaminoglycans are closely associated with the developing glandular lobules. Variations in the structure of epithelial cells undergoing morphogenesis and in the composition of the extracellular matrix are synchronous, suggesting that interactions between them may be significant in terms of the establishment and maintenance of the adult gastric gland phenotype
Descritores: Matriz Extracelular
Mucosa Gástrica/embriologia
Células Parietais Gástricas/citologia
-Actinas/análise
ATPase de Ca(2+) e Mg(2+)/análise
Diferenciação Celular
Complexo IV da Cadeia de Transporte de Elétrons/análise
Mucosa Gástrica/ultraestrutura
Glicosaminoglicanos/análise
Morfogênese
Limites: Animais
Embrião de Galinha
Tipo de Publ: Research Support, Non-U.S. Gov't
Responsável: BR1.1 - BIREME


  6 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Texto completo SciELO Brasil
Texto completo
Id: lil-218664
Autor: Cunha, V. M. N; Noel, F.
Título: (Ca2+-Mg2) ATPase in Schistosoma mansoni: evidence for heterogeneity and resistance to praziquantel
Fonte: Mem. Inst. Oswaldo Cruz;93(supl.1):181-2, Oct. 1998. graf.
Idioma: en.
Conferência: Apresentado em: Simpósio Internacional sobre Esquistossomose, 6 e Reuniäo Nacional sobre Esquistossomose, 6, Belo Horizonte, Oct. 19-24, 1997.
Descritores: ATPase de Ca(2+) e Mg(2+)/genética
Praziquantel/imunologia
Schistosoma mansoni/enzimologia
-Tapsigargina
Limites: Animais
Responsável: BR15.1 - Biblioteca de Ciências Biomédicas


  7 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-168106
Autor: Rodrigo, Ramón; Novoa, Eduardo; Thielemann, Lilian; Granata, Paulo; Videla, Luis.
Título: Mechanism of enhancement of renal (Na+ + K+) ATPase activity following chronic ethanol exposure
Fonte: Acta physiol. pharmacol. ther. latinoam;46(1):49-56, 1996. ilus, tab, graf.
Idioma: en.
Projeto: Fondo Nacional de Desarrollo Científico y Tecnológico; . Universidad de Chile. Departamento Técnico de Investigación.
Resumo: A method was devised to determine the nature of the mechanism of the increase in renal (NA++K+)-ATPase in rats fed dilute ethanol for ten weeks. Antiserum to (NA++K+)-ATPase obtained from rabbits was added to microssomal fractions of Kidney and the activities of (NA++K+)-ATPase and Mg2+ ATPase were determined. The addition of antiserum resulted in a same pattern of dose-related inhibition of (NA++K+)-ATPase activity in control and ethanol-fed rats, whereas mg2+-ATPase was not affected by the antiserum. These results suggest that the mechanism of ethanol-induced enhancement of renal (NA++K+)-ATPase activity could be explained through an increase in the number of catalytic units.
Descritores: Etanol/farmacologia
Rim/efeitos dos fármacos
ATPase Trocadora de Sódio-Potássio/metabolismo
-ATPase de Ca(2+) e Mg(2+)/metabolismo
Eletroforese em Acetato de Celulose
Eletroforese em Gel de Poliacrilamida
Soros Imunes/farmacologia
Imunoglobulina G/isolamento & purificação
Rim/metabolismo
Potássio/metabolismo
Coelhos/imunologia
Ratos Wistar
ATPase Trocadora de Sódio-Potássio/antagonistas & inibidores
ATPase Trocadora de Sódio-Potássio/isolamento & purificação
Sódio/metabolismo
Limites: Animais
Feminino
Ratos
Coelhos
Responsável: BR1.1 - BIREME


  8 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-129844
Autor: Heguilen, Ricardo Mario; Gimenez, Maria I; Imperiali, Nora; Algranati, S. Luis; Petrolito, Jose; Gracca, Irene da; Herrero, Hernan; Farias, Eduardo Dos Ramos.
Título: Alteraciones en la actividad del calcio-magnesio ATPasa en la membrana de los eritrocitos en pacientes litiasicos con hipercalciuria / Alterations in the calcium-magnesium activity ATPase in the membrane of the erytrosites in lithiasic patients with hypercalciuria
Fonte: Rev. nefrol. diál. traspl;(34):3-13, set. 1993. ilus, tab.
Idioma: es.
Resumo: La CaMgATPasa es una enzima involucrada en los movimientos de calcio a través de las membranas biológicas. Nosotros testeamos la actividad de dicha enzima en membranas de eritrocitos de 17 pacientes hipercalciúricos y la comparamos con 8 controles sanos. Los pacientes con hipercalciuria tuvieron una actividad de CaMgATPasa que fue significativamente superior a los controles (18,02 2,83 vs 14,69 1,78 nM . mg-1 p<0,01). La excreción de urinaria de calcio en 24 hs (UCa.V) estuvo directa y significativamente relacionada con la actividad de la enzima (UCa.V: 36,31 x CaMgATPasa - 371,08 r:0,65 p<0,05) sólo en pacientes con hipercalciuria. Cuando agrupamos los pacientes acorde al diagnóstico fisiopatológico en hipercalciuria absortiva (HCA) e hipercalciuria renal (HCRT) encontramos que la actividad enzimática estuvo sólo significativamente elevada en aquellos portadores de HCA al compararlos con los controles (19,17 3,49 vs 14,68 1,79 nM . mg-1 .min-1 p<0,025).No encontramos diferencias estadísticamente significativas entre HCRT y controles (16,83 1,99nM . mg-1 . min-1; p:NS) y en HCRT vs HCA (p<0,14). Concluimos que las alteraciones en el transporte de calcio en la hipercalciuria dependería de anormalidades en la actividad de la CaMgATPasa
Descritores: ATPase de Ca(2+) e Mg(2+)
Distúrbios do Metabolismo do Cálcio/enzimologia
ATPases Transportadoras de Cálcio
Cálcio/urina
Cálculos Urinários/fisiopatologia
Membrana Eritrocítica/enzimologia
-ATPase de Ca(2+) e Mg(2+)/fisiologia
Distúrbios do Metabolismo do Cálcio/classificação
Distúrbios do Metabolismo do Cálcio/etiologia
ATPases Transportadoras de Cálcio/sangue
ATPases Transportadoras de Cálcio/fisiologia
Cálcio/sangue
Cálcio/fisiologia
Cálculos Urinários/enzimologia
Cálculos Urinários/etiologia
Limites: Humanos
Masculino
Feminino
Adulto
Pessoa de Meia-Idade
Responsável: AR144.1 - CIBCHACO - Centro de Información Biomedica del Chaco


  9 / 16 LILACS  
              first record previous record next record last record
seleciona
para imprimir
Fotocópia
Id: lil-79122
Autor: Romero, Pedro J; Finol, Héctor J.
Título: Tannic acid as a marker for membrane sidedness of human red cell vesicles
Fonte: Acta cient. venez;40(2):107-12, 1989. ilus.
Idioma: en.
Projeto: Consejo de Desarrollo Cientifico y Humanistico. Universidad Central de Venezuela.
Resumo: Membrane sidedness of human eythrocytes was investigated in inside-out vesicles (IOV's), ghosts and intact cells by means of transmission electron microscopy (e.m.) after tannic acid fixation. No gross difference in appeearance of either membrane surface was observed when IOV's were subjected to conventional e.m. preparation. This included in addition to tannic acid, a double fixation with glutaraldehyde and osmium, followed by "en bloc" and thin section staining with uranyl acetate and lead citrate. By contrast, if IOV's were treated with a high EDTA concentration (2-5 mM) before tannic fixation, granular, electron-dense deposits were found on one of the surfaces. The presence of such a meterial was unaffected by neuraminidase treatment prior to the EDTA step. On the hand, red cells show no electron-dense deposits when exposed to EDTA (5 mM) unless they presented a light cytoplasm and an altered membrane appearance. Such a material was only observed on the inner membrane surface. Furthermore, a similar distribution of such deposits following EDTA treatment was also found in white ghosts before being induced to vesiculate. These results indicate that tannic acid can be employed as a marker for the cytoplasmic surface of the human erythrocyte membrane when used in combination with EDTA
Descritores: Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia
ATPases Transportadoras de Cálcio/antagonistas & inibidores
Membrana Eritrocítica/enzimologia
-Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/análogos & derivados
ATPase de Ca(2+) e Mg(2+)/sangue
ATPase Trocadora de Sódio-Potássio/sangue
Responsável: VE1.1 - Biblioteca Humberto Garcia Arocha


  10 / 16 LILACS  
              first record previous record
seleciona
para imprimir
Fotocópia
Id: lil-63367
Autor: Gajardo N., Jorge; Lecannelier F., Eduardo; Medina S., José Luis; Contreras H., Mauricio; Ibaceta O., Dino.
Título: Utilidad del ATPMgCl2 en la reducción del tamaño final del infarto agudo del miocardio / Reduction by adenosine triphosphate-magnesium chloride of miocardial necrosis
Fonte: Bol. cardiol. (Santiago de Chile);7(3):205-19, jul.-sept. 1988. tab, ilus.
Idioma: es.
Resumo: La utilidad del ATPMgCl2 para proteger a la célula del daño por la isquemia y reperfusión en diferentes órganos ha sido demostrada en numerosos trabajos de experimentación animal y últimamente en humanos. Comunicamos nuestros resultados con la utilización de esta droga en 2 grupos de animales sometidos a isquemia por oclusión aguda de la coronaria circunfleja durante 30 min. seguidos por una reperfusión de 3 horas, uno de los grupos recibió ATPMgCl2 en los primeros 30 min. de la reperfusión. Ambos grupos de animales no tuvieron diferencias significativas en sus áreas de riesgo. Observamos una disminución significativa del tamaño del infarto del grupo tratado con la droga (N=7) en relación al grupo control (N=10) (6,5 grs. v/s 3,1 grs. respectivamente p<0,05). Cuando expresamos el área infartada como porcentaje del área en riesgo, observamos una reducción en el tamaño del infarto de 29,39% a 15,97% (p<0,05). Se observó también un efecto protector significativo en la aparición de arritmias ventriculares, específicamente taquicardias ventriculares, durante la reperfusión. Concluimos que el ATPMgCl2 es una droga útil en la reducción del tamaño del infarto agudo del miocardio utilizado en el período de la reperfusión
Descritores: ATPase de Ca(2+) e Mg(2+)/uso terapêutico
Infarto do Miocárdio/tratamento farmacológico
-Infarto do Miocárdio/prevenção & controle
Limites: Cães
Animais
Tipo de Publ: Revisão
Responsável: CL1.1 - Biblioteca Central



página 1 de 2 ir para página        
   


Refinar a pesquisa
  Base de dados : Formulário avançado   

    Pesquisar no campo  
1  
2
3
 
           



Search engine: iAH v2.6 powered by WWWISIS

BIREME/OPAS/OMS - Centro Latino-Americano e do Caribe de Informação em Ciências da Saúde