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1.
Artigo em Espanhol | IBECS | ID: ibc-211455

RESUMO

La alimentación complementaria (AC) se define por la introducción de alimentos líquidos, semilíquidos o sólidos diferentes a la lactancia materna o leche de fórmula en el niño, para satisfacer las necesidades adecuadamente a partir de una determinada edad. La Organización Mundial de la Salud (OMS) entre otras sociedades recomiendan la introducción de la AC a partir de los 6 meses de edad, siempre que sean seguros y adecuados nutricionalmente [Fragmento de texto] (AU)


Assuntos
Humanos , Lactente , Enfermagem de Atenção Primária , Enfermagem Materno-Infantil , Nutrição do Lactente , Alimentos Infantis , Fórmulas Infantis , Características Culturais , Gravação em Vídeo , Espanha
2.
Artigo em Espanhol | IBECS | ID: ibc-211476

RESUMO

Las enfermeras han tenido un papel muy importante a lo largo de la historia, especialmente, en los conflictos bélicos, siendo claves en la atención y cuidados de los pacientes. Las guerras tienen como consecuencia, entre otras, el desarrollo del cuidado y terapéutica, cuya finalidad siempre ha sido ofrecer la mejor atención para la reincorporación de los soldados al campo de batalla [Fragmento de texto] (AU)


Assuntos
Humanos , História do Século XX , II Guerra Mundial , Enfermagem Militar/história
4.
Cancer Genet Cytogenet ; 152(1): 77-80, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15193447

RESUMO

The ETV6/RUNX1 rearrangement (also known as TEL/AML1) was evaluated in 39 children with B-precursor acute lymphoblastic leukemia (ALL) who had a normal karyotype or lack of mitoses. Forty-one point six percent of patients with normal karyotypes and 66.6% of patients without mitoses presented with the ETV6/RUNX1 rearrangement. In addition to this rearrangement, eight patients showed loss of the normal ETV6 allele; of three patients without mitoses, two showed an extra signal of the RUNX1 gene and the third showed the fusion gene duplicated and loss of the normal ETV6 allele. One patient without the ETV6/RUNX1 rearrangement and without mitoses showed two extra signals of the RUNX1 gene.


Assuntos
Aberrações Cromossômicas , Rearranjo Gênico , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Criança , Pré-Escolar , Bandeamento Cromossômico , Subunidade alfa 2 de Fator de Ligação ao Core , Feminino , Humanos , Lactente , Cariotipagem , Masculino , Mitose
5.
Acta Haematol ; 111(4): 196-204, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15153711

RESUMO

This in vitro study has been conducted to determine the optimal experimental conditions under which to produce canine neutrophils in long-term bone marrow cultures (LTBMC), establish functional parameters of neutrophils obtained from LTBMC and peripheral blood and to ascertain whether these cells display physiological similarities. Our aim is to provide an experimental model, enabling a correlation between hemopoietic injury and neutrophil functionality. The authors demonstrate for the first time that canine neutrophils grown in cultures are able to produce oxyradicals capable of killing bacterial products. Moreover, culture-grown neutrophils contain gelatinase granules, a marker of terminal neutrophil differentiation, and express a specific surface antigen. The results described in this article illustrate the development of a dynamic system that mimics physiological hemopoiesis.


Assuntos
Células da Medula Óssea/citologia , Neutrófilos/citologia , Neutrófilos/fisiologia , Trifosfato de Adenosina/análise , Animais , Células Sanguíneas/citologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Cães , Feminino , Gelatinases/metabolismo , Hematopoese , Modelos Biológicos , Neutrófilos/imunologia , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo , Fatores de Tempo
6.
Exp Hematol ; 26(10): 942-9, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9728929

RESUMO

We performed an in vitro study of the long-term effects of a sublethal dose (5 Gy) of x-irradiation on the survival and function of neutrophils in adult mice. For this purpose, we incubated control neutrophils harvested from long-term bone marrow cultures (LTBMCs) with supernatant withdrawn from cultures obtained in adult mice 6 or 9 months postirradiation. We noted a significant increase in superoxide anion production, NADPH, and protein levels in these cells after 3, 6, and 15 hours of incubation compared with the same cells incubated with supernatant from control LTBMCs. We also observed a delay in apoptosis that was correlated with maintenance of adenosine triphosphate levels and survival. Similar differences were found when control LTBMC neutrophils were incubated with granulocyte-macrophage colony-stimulating factor (GM-CSF) (1.3 nM). Indeed, enzyme-linked immunosorbent assay revealed a significant overproduction of this cytokine, together with higher interleukin (IL)-6 and IL-3 levels, in the supernatant from cultures of irradiated mice. Our results suggest that GM-CSF is one of the cytokines responsible for promoting the survival and activation of neutrophil function after total body irradiation.


Assuntos
Apoptose/efeitos da radiação , Fator Estimulador de Colônias de Granulócitos e Macrófagos/fisiologia , Neutrófilos/efeitos da radiação , Irradiação Corporal Total , Animais , Anticorpos Monoclonais , Proteínas Sanguíneas/metabolismo , Células da Medula Óssea/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NADP/biossíntese , Neutrófilos/patologia , Células Estromais/metabolismo , Superóxidos/metabolismo , Fatores de Tempo
7.
Br J Haematol ; 96(3): 559-65, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9054664

RESUMO

Our experiments focused on the metabolic implications of the residual haemopoietic damage in adult mice given 5 Gy X-rays. Bone marrow cells from irradiated mice exhibited an increase in protein synthesis and a decrease in ATP levels, which could be related to the enhancement of the proliferative activity of haemopoietic precursor cells. However, the kinetic parameters (Vmax and Km) of glucose uptake, the glycolytic flux and the hexose monophosphate (HMP) shunt activity were similar to those found in the control group. On the other hand, a reduction of glucose uptake (Vmax) was found in both resting and stimulated granulocytes from irradiated mice. This reduction was accompanied by a decrease in the glycolytic rate and ATP levels. However, HMP shunt activity was similar in resting granulocytes in both the control and the irradiated mice. The stimulation by PMA produced a significantly higher increase in the activity of the pathway in granulocytes from the irradiated mice and was in accordance with the enhancement of superoxide anion production that has been previously described in these cells.


Assuntos
Medula Óssea/efeitos da radiação , Glucose/metabolismo , Granulócitos/efeitos da radiação , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Medula Óssea/metabolismo , Células da Medula Óssea , Células Cultivadas , Feminino , Granulócitos/metabolismo , Hematopoese/efeitos da radiação , Hexosefosfatos/metabolismo , Camundongos , NADP/metabolismo
8.
Int J Radiat Biol ; 71(2): 215-23, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9120357

RESUMO

Haemopoietic effects in mice produced by a single acute dose of 1 Gy X-rays given on the 4th (4R) and 13th (13R) day postconception were evaluated throughout the 9-month post-irradiation. The quality of the stroma was measured in long-term bone marrow cultures (LTBMC). LTBMC granulocyte production was always markedly lower among the irradiated offspring than among controls. IL-6 supernatant levels were significantly higher in both experimental models with respect to controls. However, supernatants from 13R mice had a greater colony-stimulating activity than 4R mice and controls. Granulocytes, from culture or peripheral blood, did not show changes in their functional activity after either treatment. With regard to the content of the femoral granulocyte-macrophage colony forming cells (GM-CFC), there was an enhancement of the GM-colony number as determined from the marrow of 13R mice. In these mice, an alteration in colony size and number due to different combinations of colony-stimulating factors was observed. In summary, our results obtained with irradiation during the foetal period suggest that this 1 Gy X-rays is sufficient to produce measurable, effects on developing murine haemopoiesis.


Assuntos
Hematopoese/efeitos da radiação , Animais , Células da Medula Óssea , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Citocinas/metabolismo , Citocinas/farmacologia , Feminino , Idade Gestacional , Fator Estimulador de Colônias de Granulócitos e Macrófagos/fisiologia , Células-Tronco Hematopoéticas/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NADP/metabolismo , Gravidez , Explosão Respiratória , Superóxidos/metabolismo , Raios X
9.
Exp Hematol ; 21(9): 1227-32, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7687218

RESUMO

This paper analyzes the function of mouse granulocytes in the long term, after external irradiation with x- and gamma-rays and 239Pu contamination at different gestational ages and in a variety of culture conditions. These treatments can produce persistent defects in the stroma, which regulates hematopoiesis. Superoxide-anion production has been measured in granulocytes from peripheral blood and from long-term bone marrow cultures (LTBMC). A significant enhancement of O2- is produced using single or fractionated doses of x-rays; however, little or no increase is observed with gamma-rays. With 239Pu, enhancement of O2- depends on gestational age at contamination. The absence of hydrocortisone (HC) in LTBMC and the irradiation of the adherent layer with 15 Gy stimulate O2- production. The increased production of O2- appears to be correlated with an excess of colony-stimulating factors (CSFs) released to the supernatant by stromal cells. Neutralization with anti-granulocyte-macrophage CSF (anti-GM-CSF) monoclonal antibody shows that GM-CSF is the main factor produced. In summary, conditions that lead to residual stromal damage also result in the generation of granulocytes that are functionally primed for excess superoxide-anion production.


Assuntos
Granulócitos/fisiologia , Irradiação Corporal Total , Animais , Células da Medula Óssea , Células Cultivadas , Feminino , Fator Estimulador de Colônias de Granulócitos/farmacologia , Granulócitos/efeitos da radiação , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos , Plutônio/farmacologia , Proteínas Recombinantes/farmacologia , Células-Tronco , Superóxidos/metabolismo
10.
Int J Radiat Biol ; 63(1): 59-67, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8093468

RESUMO

Our experiments have focused on the analysis of residual haematopoietic damage in 8-day-old and 12-week-old mice X-irradiated with a single dose of 7 Gy. In the case of the adult mice, analysis of the femoral and splenic CFU-S, CFU-GM and BFU-E showed a persistent depletion of these haematopoietic progenitor cells after irradiation. In contrast, in 1-week-old irradiated mice, a progressive recovery of the femoral haematopoietic progenitors was observed, achieving essentially normal values 1 year after irradiation. The spleens of these mice, however, contained significantly less haematopoietic progenitors than the control group, mainly as a consequence of the size reduction of this organ. In the peripheral blood, normal cellularity values were observed in most cases, although in the adult group a decline in numbers or circulating cells was noted after the first year following irradiation. Long-term bone marrow cultures (LTBMCs) established 1 year after the irradiation of adult mice generated poor adherent layers, while confluent stromas were observed in flasks corresponding to 8-day-old irradiated mice. Analyses of the functional activity of granulocytes obtained from either the peripheral blood or LTBMCs revealed that both young and adult irradiated mice produced granulocytes generating high levels of superoxide anion, in relation to age-matched controls. This finding was correlated with a long-term microenvironmental activation which resulted in an overproduction of granulocyte-macrophage colony-stimulating factor.


Assuntos
Hematopoese/efeitos da radiação , Lesões Experimentais por Radiação/patologia , Fatores Etários , Animais , Células-Tronco Hematopoéticas/efeitos da radiação , Camundongos , Lesões Experimentais por Radiação/mortalidade , Taxa de Sobrevida , Irradiação Corporal Total
11.
Biosci Rep ; 12(4): 281-92, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1330056

RESUMO

This paper analyzes the long-term (6 and 12 months) function of mouse granulocytes after total body irradiation with a single dose (5 Gy) of X-rays. Superoxide anion production has been investigated in granulocytes from peripheral blood, and also in those harvested from long term bone marrow cultures, with the aim of correlating the environmental damage induced by radiation with the functional properties of granulocytes. An in vivo and in vitro enhancement of superoxide anion production and protein levels in granulocytes from irradiated mice is described. The presence of some colony stimulating factor in the supernatant of cultures from irradiated mice could play an important role in the priming of granulocytes.


Assuntos
Granulócitos/fisiologia , Hematopoese/efeitos da radiação , Animais , Células da Medula Óssea , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Técnicas In Vitro , Camundongos , Explosão Respiratória , Superóxidos/metabolismo , Fatores de Tempo , Irradiação Corporal Total , Raios X
12.
Biosci Rep ; 12(1): 29-36, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1322739

RESUMO

The effect of total body irradiation (5 Gy) on functional mouse erythroid lineage has been studied. The transferrin binding capacity by bone marrow cells and the activity of glycolytic regulatory enzymes and intracellular levels of 2,3 bisphosphoglycerate in peripheral blood erythrocytes have been determined. Results obtained along one year post-irradiation period suggest a complete recovery in the erythroid cell lineage with respect to the biological endpoints investigated.


Assuntos
Medula Óssea/efeitos da radiação , Ácidos Difosfoglicéricos/efeitos da radiação , Eritrócitos/efeitos da radiação , Fosfotransferases/efeitos da radiação , Receptores da Transferrina/efeitos da radiação , Transferrina/metabolismo , 2,3-Difosfoglicerato , Animais , Células da Medula Óssea , Ácidos Difosfoglicéricos/sangue , Eritrócitos/enzimologia , Hexoquinase/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Fosfofrutoquinase-1/efeitos da radiação , Fosfotransferases/sangue , Piruvato Quinase/efeitos da radiação , Irradiação Corporal Total
13.
Biochem Int ; 21(5): 883-90, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2147854

RESUMO

Phosphofructokinase (EC 2.7.1.11) from trout haemopoietic cells and erythrocytes exhibits biphasic behaviour, with respect to fructose 6-phosphate and MgATP in extracts filtered through Sephadex G-25. Two different values of Hill coefficient and S0.5 have been found for each cellular population. Two forms of the enzyme with high and low affinity for the substrates, were obtained after affinity chromatography in each cellular population. The kinetic behaviour of these forms is different and may be due to a distinct composition and/or proportion and contribution of phosphofructokinase isoenzymes in both types of cells.


Assuntos
Hematopoese , Isoenzimas/metabolismo , Fosfofrutoquinase-1/metabolismo , Truta/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Frutosefosfatos/metabolismo , Cinética
14.
Biosci Rep ; 10(2): 141-54, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2357482

RESUMO

Pyruvate kinase studies in the granulocyte-macrophage lineage during in vitro differentiation have been performed using culture techniques on GM-CFC cells and a study has also been done in bone marrow cells. The enzyme exhibits biphasic behaviour with respect to both of its substrates in cells derived from in vitro cultures at 5 and 7 days of incubation period. However in bone marrow cells these kinetics are only observed for ADP. The different kinetic behaviour of pyruvate kinase toward Fru-1,6-P2, Ala, Phe and ATP in the three cellular populations allows us to conclude that the expression of pyruvate kinase is associated with the differentiation of these cells.


Assuntos
Medula Óssea/enzimologia , Granulócitos/citologia , Células-Tronco Hematopoéticas/enzimologia , Macrófagos/citologia , Piruvato Quinase/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Alanina/metabolismo , Animais , Células da Medula Óssea , Diferenciação Celular , Células Cultivadas , Feminino , Frutosedifosfatos/metabolismo , Granulócitos/enzimologia , Células-Tronco Hematopoéticas/citologia , Concentração de Íons de Hidrogênio , Cinética , Macrófagos/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Fenilalanina/metabolismo , Fosfoenolpiruvato/metabolismo
15.
Biochem Int ; 21(4): 771-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2146960

RESUMO

Thermic and pH modulation of phosphofructokinase (EC 2.7.1.11) activity with respect to fructose 6-phosphate has been studied comparatively in trout (Salmo gairdneri R.) haemopoietic cells and erythrocytes. Phosphofructokinase of both cellular populations displays a biphasic kinetic behaviour with respect to fructose 6-phosphate at two values of pH and temperature. In haemopoietic cells, when pH decreases the enzyme-substrate affinity increase while an opposite effect is found in erythrocytes. Decreases in temperature act as a positive modulator in haemopoietic cells while in erythrocytes this effect is observed only at low fructose 6-phosphate concentrations. Therefore a different pH and temperature modulation of phosphofructokinase during trout haemopoiesis has been established.


Assuntos
Frutosefosfatos/metabolismo , Hematopoese/fisiologia , Fosfofrutoquinase-1/metabolismo , Animais , Diferenciação Celular , Eritrócitos/metabolismo , Sistema Hematopoético/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Truta
16.
Comp Biochem Physiol B ; 95(4): 705-10, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2140545

RESUMO

1. The regulatory properties of phosphofructokinase (PFK) has been investigated in two cellular population representatives of trout haemopoiesis; haemopoietic cells (capable of replication and differentiation) and erythrocytes (highly specialized cells). 2. The intracellular levels of substrates and effectors have been quantified and their effect on PFK activity determined. 3. Fructose 1,6-bisphosphate anc cyclic AMP show a higher activation of the PFK from haemopoietic cells than the enzyme from erythrocytes. 4. AMP and phosphoenolpyruvate act as activators of the haemopoietic cell PFK while for erythrocytes PFK, AMP is an inhibitor and phosphoenolpyruvate does not display any effect. 5. Citrate inhibits PFK activity from haemopoietic cells but was not assayed in erythrocytes since it was not detected in these cells. 6. The differences in PFK regulation in both cellular populations may be attributed to the intracellular levels of the effectors and/or different isoenzymatic patterns. 7. The different regulation of PFK together with the higher enzymatic activity of PFK and pyruvate kinase from haemopoietic cells are related to the higher glycolytic flux that exhibits the haemopoietic cells. 8. The results shown in this investigation allow us to conclude that PFK has a specific role depending on the energetic requirements of the cellular population in which the enzyme is present. 9. The requirements are related to the physiological function of each type of cell.


Assuntos
Glicólise/fisiologia , Hematopoese/fisiologia , Fosfofrutoquinase-1/metabolismo , Salmonidae/metabolismo , Truta/metabolismo , Animais , Medula Óssea/metabolismo , Células da Medula Óssea , Diferenciação Celular , Eritrócitos/metabolismo , Piruvato Quinase/metabolismo , Truta/anatomia & histologia
17.
Biochimie ; 71(6): 763-6, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2502191

RESUMO

Pyruvate kinase modulation by L-alanine and L-phenylalanine was studied in cells obtained from in vitro culture of GM-CFC at different stages of development. L-Alanine and L-phenylalanine exhibit different inhibition behaviour at both differentiation stages and at various PEP concentration ranges. Therefore, a change in PK expression during granulocyte-macrophage development is suggested.


Assuntos
Alanina/farmacologia , Granulócitos/enzimologia , Macrófagos/enzimologia , Fenilalanina/farmacologia , Piruvato Quinase/metabolismo , Animais , Diferenciação Celular , Técnicas In Vitro , Cinética , Camundongos , Piruvato Quinase/antagonistas & inibidores , Especificidade por Substrato
18.
Comp Biochem Physiol B ; 74(4): 801-5, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6861476

RESUMO

1. Temperature acts as a pyruvate kinase regulator in haematopoietic cells and erythrocytes. 2. Fructose-1,6-biphosphate and alanine act as allosteric modulators of pyruvate kinase in haematopoietic cells, while in erythrocytes although fructose-1,6-biphosphate exerts also allosteric effect, alanine appears to be a competitive inhibitor. ATP (1.0 mM) does not exert any clear effect on pyruvate kinase of both cellular populations. 3. The level of specific activity of pyruvate kinase in haematopoietic cells is 40-fold that of PK from erythrocytes.


Assuntos
Eritrócitos/enzimologia , Sistema Hematopoético/enzimologia , Piruvato Quinase/análise , Salmonidae/metabolismo , Truta/metabolismo , Trifosfato de Adenosina/farmacologia , Alanina/farmacologia , Animais , Frutosedifosfatos/farmacologia , Concentração de Íons de Hidrogênio , Cinética , Temperatura
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