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1.
J Theor Biol ; 561: 111393, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36572091

RESUMO

Computational models allow to explain phenomena that cannot be observed through an animal model, such as the strain and stress states which can highly influence regeneration of the tissue. For this purpose, we have developed a simulation tool to determine the mechanical conditions provided by the polymeric scaffold. The computational model considered the articular cartilage, the subchondral bone, and the scaffold. All materials were modeled as poroelastic, and the cartilage had linear-elastic oriented collagen fibers. This model was able to explain the remodeling process that subchondral bone goes through, and how the scaffold allowed the conditions for cartilage regeneration. These results suggest that the use of scaffolds might lead the cartilaginous tissue growth in vivo by providing a better mechanical environment. Moreover, the developed computational model demonstrated to be useful as a tool prior experimental in vivo studies, by predicting the possible outcome of newly proposed treatments allowing to discard approaches that might not bring good results.


Assuntos
Cartilagem Articular , Células-Tronco Mesenquimais , Animais , Alicerces Teciduais , Osso e Ossos , Engenharia Tecidual/métodos
2.
Free Radic Res ; 47(8): 593-601, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23678888

RESUMO

Inflammation results in the production of free radicals. We evaluated the anti-inflammatory and antioxidant capacity of lipoic acid in an experimental uveitis model upon a subcutaneous injection of endotoxin into Lewis rats. The role of oxidative stress in the endotoxin-induced uveitis model is well-known. Besides, the Th1 response classically performs a central part in the immunopathological process of experimental autoimmune uveitis. Exogenous sources of lipoic acid have been shown to exhibit antioxidant and anti-inflammatory properties. Our results show that lipoic acid treatment plays a preventive role in endotoxin-induced oxidative stress at 24 h post-administration and reduced Th1 lymphocytes-related cytokines by approximately 50-60%. Simultaneously, lipoic acid treatment caused a significant reduction in uveal histopathological grading and in the protein concentration in aqueous humors, but not in cellular infiltration.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Citocinas/metabolismo , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Ácido Tióctico/farmacologia , Uveíte/tratamento farmacológico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Antioxidantes/administração & dosagem , Citocinas/imunologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipopolissacarídeos , Masculino , Ratos , Ratos Endogâmicos Lew , Células Th1/metabolismo , Ácido Tióctico/administração & dosagem , Uveíte/induzido quimicamente , Uveíte/metabolismo
3.
Rev Clin Esp ; 209(4): 168-75, 2009 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-19457323

RESUMO

BACKGROUND: It was aimed to compare urine B-type natriuretic peptide (BNP) according to left ventricular systolic dysfunction and to investigate its diagnostic value in heart failure (HF) patients. MATERIAL AND METHODS: A total of 90 HF outpatients (61 men, age 66 +/- 12) and 30 age- and gender-matched controls were studied. RESULTS: An increase in urine BNP was observed in patients with EF 40% (p < 0.0001), and controls (p < 0.0001). Significant correlations between urinary BNP and left ventricular functional parameters were obtained. A multivariate regression analysis was performed and the best model associated with urine BNP included plasma BNP (p < 0.0001), EF (p = 0.02) and LV volume indexes (p < 0.0001). The ROC for detection of EF

Assuntos
Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/urina , Peptídeo Natriurético Encefálico/urina , Disfunção Ventricular/complicações , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Estudos Prospectivos
4.
Transplant Proc ; 40(9): 3012-3, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010175

RESUMO

OBJECTIVE: The objective of this study was to describe heart rate turbulence (HRT) in advanced heart failure (HF) patients and in a group of patients who underwent heart transplantation (HT). MATERIALS AND METHODS: We performed 24-hour Holter recordings in 20 patients with advanced HF referred to our hospital for HT, including 16 males of overall mean age of 44 +/- 13 years and with a mean ejection fraction (EF) 21 +/- 7%. An additional set of recordings was obtained in a second group of 27 patients who had already undergone HT, including of 21 males of overall mean age of 47 +/- 14 years. We recorded the number of premature ventricular contractions (PVCs), mean heart rate (MHR), and 2 parameters of HRT-turbulence onset (TO) and turbulence slope (TS). RESULTS: Patients with HT showed a low density of premature ventricular complexes, in contrast to patients in the advanced HF group. For this reason, HRT could only be analyzed in 15 of the patients with advanced HF (66%) and in 10 of the patients who underwent HT (37%). MHR was 77 +/- 10 bpm in the advanced HF group and 90 +/- 10 bpm in the HT group. In both groups, TO and TS showed highly attenuated values. CONCLUSIONS: Patients with advanced HF showed a high number of PVCs with attenuated HRT parameters, reflecting increased circulating catecholamine levels and decreased response of the autonomic nervous system. Patients who underwent HT showed elevated MHRs, a small number of PVCs, and attenuated HRT values, as corresponds to a denervated heart.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/fisiologia , Transplante de Coração/fisiologia , Adulto , Eletrocardiografia Ambulatorial/métodos , Feminino , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
5.
Arch. Soc. Esp. Oftalmol ; 82(12): 757-762, dic. 2007. ilus, tab
Artigo em Es | IBECS | ID: ibc-058303

RESUMO

Objetivo: Establecer la existencia de cambios bioquímicos y funcionales en la retina tras la administración crónica de etanol en ratas adultas, y estudiar la capacidad del antioxidante ebselen para corregir estos efectos. Métodos: Se utilizaron ratas macho Sprague-Dawley, que fueron alimentadas con una dieta líquida con etanol, mientras el grupo control recibió una dieta isocalórica libre de etanol. Después de seis semanas, los ojos fueron extraídos y homogenizados sin cristalino, y se determinaron parámetros relevantes en la modulación del estrés oxidativo, tales como el contenido de glutation (GSH) y de malondialdehído (MDA) como antioxidante intracelular y producto de la peroxidación de lípidos, respectivamente. Además, se comprobó la funcionalidad de la retina mediante electrorretinograma (ERG). Resultados: La concentración de MDA en la retina fue significativamente mayor en el grupo alimentado con etanol, mientras el contenido de GSH fue significativamente menor en este grupo, al compararlo con el grupo control. El etanol también indujo una disminución de la onda b del ERG. El tratamiento con ebselen fue capaz de corregir los valores de MDA, GSH y la amplitud de la onda b en el ERG hasta valores control. Conclusión: Estos resultados indican que la ingesta crónica de etanol como único factor etiológico, altera el estado redox de la retina así como su función (ERG), descartando la influencia del estado nutricional. Aun así, son necesarios nuevos estudios para confirmar el mecanismo protector del ebselen en este modelo del alcoholismo crónico


Purpose: To assess the involvement of biochemical and functional changes to the retina after chronic ethanol intake in adult rats, and the capacity of the antioxidant ebselen to prevent these changes. Methods: Male Sprague-Dawley rats were used in the study. They were fed an ethanol-containing liquid diet, whereas a control group was given an ethanol-free isocaloric diet. After six weeks of experiment, the eyes were extracted and homogenized without the lens, and markers of oxidative stress were assayed, i.e., glutathione (GSH) and malondialdehyde (MDA) as an intracellular antioxidant and a lipid peroxidation product, respectively. Moreover, retinal function was assessed by electroretinogram (ERG). Results: The retinal MDA concentration was significantly increased in the ethanol-fed animals compared to controls, whereas the GSH content was significantly reduced in the ethanol-fed group compared to controls. Ethanol also induced a decrease in ERG b-wave amplitude. Ebselen treatment restored the MDA and GSH concentrations and ERG bwave amplitude to control values. Conclusion: These results indicate that chronic alcohol consumption alone and without the influence of nutritional factors alters the retinal redox status as well as its function (ERG). Further studies are required to better understand the protective mechanism of ebselen in this experimental model of chronic alcoholism


Assuntos
Animais , Ratos , Masculino , Estresse Oxidativo , Retina , Retina/patologia , Doenças Retinianas/induzido quimicamente , Etanol/uso terapêutico , Antioxidantes/uso terapêutico , Peroxidação de Lipídeos , Glutationa/uso terapêutico , Glutationa Peroxidase/uso terapêutico , Ambliopia/complicações , Doenças do Nervo Óptico/complicações , Doenças do Nervo Óptico/diagnóstico
6.
Arch Soc Esp Oftalmol ; 82(12): 757-62, 2007 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-18040919

RESUMO

PURPOSE: To assess the involvement of biochemical and functional changes to the retina after chronic ethanol intake in adult rats, and the capacity of the antioxidant ebselen to prevent these changes. METHODS: Male Sprague-Dawley rats were used in the study. They were fed an ethanol-containing liquid diet, whereas a control group was given an ethanol-free isocaloric diet. After six weeks of experiment, the eyes were extracted and homogenized without the lens, and markers of oxidative stress were assayed, i.e., glutathione (GSH) and malondialdehyde (MDA) as an intracellular antioxidant and a lipid peroxidation product, respectively. Moreover, retinal function was assessed by electroretinogram (ERG). RESULTS: The retinal MDA concentration was significantly increased in the ethanol-fed animals compared to controls, whereas the GSH content was significantly reduced in the ethanol-fed group compared to controls. Ethanol also induced a decrease in ERG b-wave amplitude. Ebselen treatment restored the MDA and GSH concentrations and ERG b-wave amplitude to control values. CONCLUSION: These results indicate that chronic alcohol consumption alone and without the influence of nutritional factors alters the retinal redox status as well as its function (ERG). Further studies are required to better understand the protective mechanism of ebselen in this experimental model of chronic alcoholism.


Assuntos
Antioxidantes/uso terapêutico , Azóis/uso terapêutico , Etanol/administração & dosagem , Compostos Organosselênicos/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Retina/efeitos dos fármacos , Retina/metabolismo , Animais , Etanol/efeitos adversos , Isoindóis , Masculino , Ratos , Ratos Sprague-Dawley
7.
Neurosci Lett ; 288(1): 53-6, 2000 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-10869814

RESUMO

Although cultured astroglial cells were reported to express exclusively the truncated non-catalytic Trk B receptor for brain-derived neurotrophic factor (BDNF), we detect here, using a sensitive ribonuclease protection assay, mRNAs for both truncated (TrkB-T) and the full length catalytic (TrkB-fl) form of BDNF receptor in developing cortical astrocytes and neurons in culture. Cortical neurons and immature astroglia, such as radial glia and proliferating astrocytes, express both the protein and mRNAs for TrkB-fl and TrkB-T, whereas the differentiation of astrocytes leads to a decrease in the trkB-fl mRNA, being the truncated TrkB the predominant receptor in differentiating and confluent astrocytes. The levels of TrkB-fl expression in proliferating and differentiating astrocytes and neurons correlates with the cell response to BDNF, monitored by the rise in intracellular [Ca(2+)](i). Foetal exposure to ethanol alters astroglial development and delays the reduction in trkB-fl mRNA levels observed with differentiation of astrocytes. These results demonstrate that immature astrocytes are able to express the catalytic Trk B receptors and to respond to BDNF with the activation of conventional signal transduction pathways. The results suggest that this signalling pathway is more activated in ethanol-exposed cells.


Assuntos
Astrócitos/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Cálcio/metabolismo , Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Receptor trkB/genética , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Feto/citologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , RNA Mensageiro/análise , Ratos
8.
Int J Dev Biol ; 44(2): 209-21, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10794079

RESUMO

Endocytosis constitutes an essential process in the regulation of the expression of cell surface molecules and receptors and, therefore, could participate in the neural-glial interactions occurring during brain development. However, the relationship between endocytic pathways in astroglial cells under physiological and pathological conditions remains poorly understood. We analyzed the endocytosis and transcytosis processes in growing astrocytes and the possible effect of ethanol on these processes. Evidence demonstrates that ethanol affects endocytosis in the liver and we showed that ethanol exposure during brain development alters astroglial development changing plasma membrane receptors and surface glycoprotein composition. To study these processes we use several markers for receptor-mediated endocytosis, fluid phase endocytosis and non-specific endocytosis. These markers were labeled for fluorescence microscopy and electron microscopy. 125I-BSA was used to study the effect of ethanol on the internalization and recycling of this macromolecule. The distribution of several proteins involved in endocytosis (caveolin, clathrin, rab5 and beta-COP) was analyzed using immunofluorescence, immunoelectron microscopy and immunoblotting. Our results indicate that growing astrocytes have a developed endocytic system mainly composed of caveolae, clathrin coated pits and vesicles, tubulo-vesicular and spheric endosomes, multivesicular bodies and lysosomes. Ethanol exposure induces a fragmentation of tubular endosomes, decreases the internalization of 125I-BSA, alters the processing of internalized BSA, and decreases the levels of caveolin, clathrin, rab5 and beta-COP. These results indicate that ethanol alters the endocytosis and transcytosis processes and impairs protein trafficking in astrocytes, which could perturb astrocyte surface expression of molecules involved in neuronal migration and maturation during brain development.


Assuntos
Astrócitos/metabolismo , Caveolinas , Endocitose , Neurônios/fisiologia , Animais , Astrócitos/efeitos dos fármacos , Western Blotting , Encéfalo/embriologia , Caveolina 1 , Células Cultivadas , Depressores do Sistema Nervoso Central/farmacologia , Clatrina/metabolismo , Proteína Coatomer/metabolismo , Etanol/farmacologia , Ferritinas/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Microscopia Eletrônica , Microscopia de Fluorescência , Neurônios/efeitos dos fármacos , Ratos , Albumina Sérica/metabolismo , Fatores de Tempo , Proteínas rab5 de Ligação ao GTP/metabolismo
9.
Glia ; 24(4): 415-27, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9814822

RESUMO

Neural cell adhesion molecules (NCAMs) constitute a group of cell surface glycoproteins that control cell-cell interactions and play important morphoregulatory roles in the developing and regenerating nervous system. NCAMs exist in a variety of isoforms differing in the cytoplasmic domain and/or their content in sialic acid. The highly sialylated form (PSA-NCAM) is expressed by neurons, whereas it is believed that the less sialylated NCAM forms are synthesised by astrocytes. Moreover, little is known about the molecular sequence of the events that contribute to its expression at the cell surface. Here we report that during the proliferation of cortical astrocytes, at 4 days in primary culture, these cells expressed PSA-NCAM as well as NCAM 180. Then, during cell differentiation these isoforms progressively disappeared and the NCAM 140 became predominant. By immunofluorescence and immunocytochemistry studies we also show that PSA-NCAM and NCAM are first observed in small cytoplasmic spots or vesicles, located in or near the Golgi apparatus, as demonstrated by their co-localization with labelled wheat germ agglutinin (WGA) in this cell organelle. Thereafter, immunostained cytoplasmic NCAM gradually disappeared and became detectable at the cell surface of differentiating astrocytes. We also describe for the first time sialyltransferase activity in these cells and report that the levels of this activity correlated with the decrease in PSA-NCAM expression during the differentiation of astrocytes. These results will contribute to our understanding of the PSA and NCAM intracellular transport pathways and their expression at the cell surface. Moreover, the presence of PSA-NCAM in astrocytes suggests their possible role in nerve branching, fasciculation, and synaptic plasticity.


Assuntos
Astrócitos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Animais , Astrócitos/citologia , Western Blotting , Diferenciação Celular , Divisão Celular , Células Cultivadas , Córtex Cerebral/citologia , Técnica Indireta de Fluorescência para Anticorpo , Imuno-Histoquímica , Líquido Intracelular/metabolismo , Ratos , Sialiltransferases/metabolismo , beta-D-Galactosídeo alfa 2-6-Sialiltransferase
10.
J Neurochem ; 67(6): 2425-33, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8931475

RESUMO

The alterations in astrocyte proliferation and differentiation induced by prenatal exposure to alcohol (PEA) suggest that ethanol exposure affects the radial glial cells, the main astrocytic precursors. We have investigated the effects of ethanol on the early stages of astrogliogenesis by analyzing the developmental pattern of vimentin and glial fibrillary acidic protein (GFAP) immunoreactivity and their mRNA levels during embryonic/fetal brain development and in radial glia in primary culture. GFAP appeared late in gestation and at day 5 of culture of radial glia, whereas GFAP mRNA was first detected on fetal day 15 and increased in content on fetal day 21. In contrast, the levels of vimentin and its mRNA were high at fetal day 15 but decreased on day 21. Alcohol exposure delays the appearance of GFAP and its mRNA and significantly decreases the GFAP expression in fetal brain and in primary culture of radial glia. In addition, some morphological alterations were observed in PEA glial cells in culture. These results demonstrate that astroglial precursor cells are damaged by prenatal exposure to ethanol and suggest that abnormalities in the astrogliogenesis may underlie the disruption in neuronal migration and other CNS alterations observed after prenatal ethanol exposure.


Assuntos
Química Encefálica/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Proteína Glial Fibrilar Ácida/genética , Neuroglia/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Animais , Northern Blotting , Western Blotting , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas/química , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Córtex Cerebral/crescimento & desenvolvimento , Citoesqueleto/química , Feminino , Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/análise , Masculino , Neuroglia/fisiologia , Gravidez , RNA Mensageiro/análise , Ratos , Ratos Wistar , Frações Subcelulares/química , Vimentina/análise , Vimentina/genética
11.
Rev Esp Cardiol ; 49(6): 477-9, 1996 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-8753915

RESUMO

Doppler-echocardiography has proved useful in the assessment of mediastinal masses. We present the case of a young man with fever and new systolic murmur. Echocardiographic examination revealed a paracardiac mass compressing the right ventricular outflow tract and Doppler flow study detected marked acceleration in luminal narrowing. Complete remission of the tumour was obtained with subtotal resection and chemotherapy. Histological diagnosis was of embryonary carcinoma with areas of endodermic sinus. A new Doppler-echocardiography study showed disappearance of both the mass and the compression and showed normal right ventricular outflow tract flow.


Assuntos
Carcinoma Embrionário/complicações , Neoplasias do Mediastino/complicações , Obstrução do Fluxo Ventricular Externo/etiologia , Adulto , Carcinoma Embrionário/terapia , Ecocardiografia Doppler , Humanos , Masculino , Neoplasias do Mediastino/terapia , Indução de Remissão , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/terapia
12.
J Neurochem ; 65(6): 2561-70, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7595552

RESUMO

We demonstrate the presence of cytochrome P4502E1 (CYP2E1) in astrocytes in primary culture, its induction by ethanol, and the concomitant generation of free radical species. Double immunofluorescence using anti-CYP2E1 and anti-glial fibrillary acidic protein showed that CYP2E1 was distributed over the cytoplasm and processes, although labeling was more pronounced over the nuclear membrane. Immunogold labeling confirmed this pattern of distribution. Addition of 25 mM ethanol to the astrocyte culture medium for 14 days resulted in an increase in the CYP2E1 content, as determined by confocal microscopy and dot blot. In addition, ethanol induced a dose-dependent increase in the formation of reactive oxygen species that was partially prevented by incubating the astrocytes with anti-CYP2E1. Alcohol also induced a dose-dependent increase in malonaldehyde and hydroxynonenal formation and a depletion of the glutathione (GSH) content. These results suggest that ethanol induces oxidative damage in astrocytes, which could explain some of the toxic effects of ethanol on these cells, such as cytoskeletal alterations. This assumption is supported here by the fact that an increase in GSH content prevents the deleterious effects of alcohol on the cytoskeleton of astrocytes. These results suggest the importance of oxidative stress as a mechanism involved in alcohol-induced neural and brain damage.


Assuntos
Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Etanol/farmacologia , Estresse Oxidativo , Oxirredutases N-Desmetilantes/metabolismo , Animais , Células Cultivadas , Citocromo P-450 CYP2E1 , Glutationa/metabolismo , Peróxidos Lipídicos/metabolismo , Microssomos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo
13.
Am J Obstet Gynecol ; 173(5): 1470-7, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7503187

RESUMO

OBJECTIVE: Our purpose was to determine the ability of an ovarian epithelial carcinoma cell line, Caov-3, to alter the bioactivity of exogenously added tumor necrosis factor-alpha. STUDY DESIGN: Caov-3 cells were cultured for up to 6 days in Dulbecco's modified Eagle's medium containing 10% fetal calf serum. The control and tumor necrosis factor-alpha-treated cells were analyzed for proliferation, distribution throughout the cell cycle by flow cytometry, their ability to release bioactive tumor necrosis factor-alpha by L929 bioassay, and their ability to release immunoreactive tumor necrosis factor-alpha by a specific double sandwich enzyme-linked immunosorbent assay. RESULTS: Tumor necrosis factor-alpha induced a dose- and time-dependent inhibition of cell proliferation accompanied by accumulation of cells in late S and G2/M phases of the cell cycle. Tumor necrosis factor-alpha bioactivity was undetectable in the media of control Caov-3 cell cultures, but these cells exhibited TNF-alpha messenger ribonucleic acid. After culture of the cells for 2 days in the presence of various doses of TNF-alpha (0.1, 1.0, 10, or 100 ng/ml), a significant decline (p < 0.01) in bioactivity was observed in all groups with the exception of 100 ng of TNF-alpha. Further declines in bioactivity were observed 2 and 4 days later. Addition of TNF-alpha to Caov-3 cells did not affect its immunoactivity, and Western blots of media revealed major bands of immunoactivity at approximately 17 kd, the expected molecular size of TNF-alpha. CONCLUSION: These results indicate that Caov-3 ovarian carcinoma cells reduce the bioactivity of TNF-alpha, an important growth regulator, by a novel yet unknown mechanism to escape the modulatory effects of the normal immune response during cancer cell growth.


Assuntos
Ciclo Celular/fisiologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/farmacologia , Animais , Northern Blotting , Carcinoma , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Linhagem Celular , Meios de Cultivo Condicionados , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Expressão Gênica , Humanos , Cinética , Células L , Camundongos , Neoplasias Ovarianas , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Fatores de Tempo , Células Tumorais Cultivadas
14.
Glia ; 15(2): 157-66, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8567067

RESUMO

In the present study we analyze the events which occur during the early stages of astrogliogenesis by examining the pattern of both GFAP and vimentin gene expression and their corresponding immunoreactive proteins during rat brain development. This study was carried out "in vivo" (whole brain) and "in vitro" (primary culture of radial glia) using immunofluorescence, immunoblotting, and Northern blot analysis. Our results demonstrate that although GFAP immunostaining appeared late in gestation and at day 5 in radial glia cultures, GFAP mRNA expression was first detected, at very low levels, on fetal (F) day 15 and increased to F21. During postnatal development a striking increase in GFAP and its encoding messenger occurs. In contrast, the levels of vimentin and its mRNA expression were very high during the fetal stage (F15 to F21). Thereafter vimentin expression declined during postnatal (P) development until P21 and then remained constant at adult levels. In contrast, an increase in vimentin expression was observed in glial cells throughout the entire culture period. The biological significance of the developmental patterns of GFAP and vimentin expression in astroglial cells. during brain development is discussed.


Assuntos
Encéfalo/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteína Glial Fibrilar Ácida/biossíntese , Neuroglia/metabolismo , Vimentina/biossíntese , Animais , Northern Blotting , Western Blotting , Encéfalo/citologia , Encéfalo/metabolismo , Células Cultivadas , Citoesqueleto/metabolismo , Sondas de DNA , Feminino , Técnica Direta de Fluorescência para Anticorpo , Proteína Glial Fibrilar Ácida/genética , Immunoblotting , Microscopia de Fluorescência , Neuroglia/efeitos dos fármacos , RNA/biossíntese , Ratos , Ratos Wistar , Vimentina/genética
15.
Virchows Arch ; 427(3): 309-15, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7496602

RESUMO

Alcohol consumption during pregnancy is teratogenic and induces severe alterations in hepatocytes. In the hepatocyte peroxisomal system, ethanol is converted in the presence of H2O2 to acetaldehyde and water. Therefore, peroxisomal catalase also acts as an antioxidant defence mechanism by removing H2O2 and preventing the formation of hydroxyl radicals in the cell. Alterations in peroxisomal catalase after pre- and pre+postnatal alcohol exposure were investigated in the rat. The effect of pre- and postnatal exposure to ethanol on hepatocyte subpopulations was analysed in isolated hepatocytes originating from periportal, intermediate and perivenous zones. Analysis of catalase revealed that the total activity and content of this enzyme were higher in 12-day-old cells than in cells from newborns and that this increment was more pronounced in treated cells. In controls, the amount of peroxisomal catalase increased mainly in periportal cells, whereas alcohol exposure induced a significant increase in the catalase of perivenous hepatocytes. We conclude that pre- and postnatal alcohol exposure mainly affects the perivenous hepatocyte peroxisomes and that the increase in peroxisomal catalase could constitute a defence mechanism against free radical generation induced by alcohol exposure during the perinatal period.


Assuntos
Catalase/metabolismo , Etanol/farmacologia , Fígado/enzimologia , Microcorpos/enzimologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Animais Recém-Nascidos , Etanol/administração & dosagem , Feminino , Immunoblotting , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Gravidez , Ratos , Fatores de Tempo
16.
Biol Reprod ; 48(4): 707-14, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8485234

RESUMO

Ovarian cells that transcribe and translate the gene for tumor necrosis factor alpha (TNF alpha) were identified in the adult cyclic mouse by using in situ hybridization and immunocytochemistry. TNF alpha mRNA was observed in > 97% and protein was contained in approximately 53% of the oocytes of healthy follicles with two or more layers of granulosa cells, but neither was detectable in oocytes of primordial follicles and follicles with a single layer of granulosa cells. In early atretic follicles, only 13% contained TNF alpha protein and 40% contained TNF alpha mRNA. In late stages of atresia, intense immunoreactive TNF alpha was observed in all of the oocytes, but TNF alpha mRNA was present in only 13%. In approximately 85% of follicles, theca and/or granulosa cells exhibited TNF alpha mRNA hybridization signals. Macrophage-like cells within the interstitium were positive for TNF alpha mRNA and protein. In corpora lutea, luteal cells and macrophage-like cells contained TNF alpha message, while only the latter lineage contained immunoreactive TNF alpha. Hybridization signals and immunoreactivity were more intense in older corpora lutea than in corpora lutea of the present cycle. Northern blot analysis revealed a 2.2-kb TNF alpha mRNA in the ovary that was unchanged relative to 28S rRNA (constitutive RNA) during the cycle. Similarly, TNF alpha hybridization signals and immunoreactivity did not appear to change throughout the cycle. These results indicate that TNF alpha gene transcription in the oocyte coincides with the synthesis of immunoreactive TNF alpha and that these complex biochemical processes occur at distinct steps of follicular development in the mouse.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Oócitos/metabolismo , Folículo Ovariano/metabolismo , Fator de Necrose Tumoral alfa/genética , Animais , Feminino , Expressão Gênica , Células da Granulosa/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Folículo Ovariano/citologia , Folículo Ovariano/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tecais/metabolismo , Transcrição Gênica , Fator de Necrose Tumoral alfa/biossíntese
17.
J Endocrinol ; 135(3): 571-8, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1283178

RESUMO

We investigated whether human granulosa-luteal (GL) cells exhibited lipopolysaccharide (LPS)-binding protein, and the response of follicular aspirate cells to LPS in vitro. Follicular aspirates taken from a human in-vitro fertilization and gamete intra-fallopian-tube transfer programme were subjected to Percoll gradients in order to isolate an enriched population of GL cells. GL cells exhibited specific LPS-binding protein, detected by autoradiography of the cellular lysate on SDS-PAGE after the cells were specifically labelled with a radioiodinated, photoactivable and reducible LPS derivative. LPS binding to the cells was also detected by the appearance of immunofluorescence associated with the cellular membrane when incubated with a fluorescent conjugated LPS receptor antibody. Ninety-four per cent of the cells exhibiting immunofluorescent LPS-binding protein were also positive for the steroidogenic enzyme 3 beta-hydroxysteroid dehydrogenase, as detected by cytochemistry. In order to detect a response to LPS, the enriched population of GL cells were cultured in vitro in the presence or absence of LPS; after 16 h of culture, tumour necrosis factor-alpha (TNF) mRNA was detected by reverse transcription-polymerase chain reaction and Southern blot analysis of the amplified cDNA. The expression of TNF mRNA was enhanced when the cells were cultured in the presence of LPS, which also significantly enhanced TNF secretion into the media during the 16-h period. These results reveal that GL cells exhibit LPS-binding protein and thus increased TNF secretion occurs in response to LPS in follicular aspirate cells. The source of ovarian TNF may be leukocytes, macrophages and/or GL cells.


Assuntos
Proteínas de Transporte/metabolismo , Células da Granulosa/metabolismo , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana , 3-Hidroxiesteroide Desidrogenases/metabolismo , Proteínas de Fase Aguda , Autorradiografia , Células Cultivadas , Feminino , Humanos , Fator de Necrose Tumoral alfa/metabolismo
18.
Endocrinology ; 130(3): 1359-64, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1537297

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) messenger RNA (mRNA) in rat ovaries was detected by Northern blot analysis and by reverse transcription-polymerase chain reaction (RT-PCR). Northern blot analysis of total cellular RNA (tcRNA) isolated from adult rat ovaries showed a single distinct band at approximately 2 kilobases, while rat white blood cells, used as control, also showed a second lower band at approximately 0.5 kilobases. TNF-alpha expression in ovaries was also detected by RT-PCR, using RNA-specific primers. Southern blot analysis of the RT-PCR products showed a single band of the expected 500 base pairs, from the ovary and white blood cells, using either tcRNA or polyA+ RNA. In order to validate the RT-PCR product, it was digested with restriction enzymes, HhaI, HindIII, and XhoI. The results indicate that the ovarian TNF-alpha mRNA does not contain major alterations with respect to the known structure of rat TNF-alpha mRNA. Ovarian RNA was also subjected to PCR without previous RT in order to amplify, if any, contaminating genomic DNA. A single band of approximately 900 base pairs was observed, which contained introns 1 and 2 (determined by restriction enzyme digestion). In summary, these results indicate that rat ovaries contain TNF-alpha mRNA which makes it a likely source of local TNF-alpha secretion. The possibility exists that ovarian cells and/or macrophages are the source of the ovarian TNF-alpha mRNA.


Assuntos
Expressão Gênica/genética , Ovário/química , Fator de Necrose Tumoral alfa/genética , Animais , Sequência de Bases , Southern Blotting , DNA/genética , Feminino , Dados de Sequência Molecular , Ovário/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo
19.
Rev Esp Cardiol ; 45(1): 67-70, 1992 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-1549764

RESUMO

We present an adult with echocardiographic diagnosis of cor triatriatum. Continuous wave Doppler echocardiography was able to assess correctly the severity of the left ventricular inflow obstruction caused by the intra-atrial membrane. Even though the diagnosis was confirmed by catheterization, the surgical decision was based in noninvasive data. Postoperative Doppler echocardiography proved the disappearance of the intra-atrial obstruction. The anatomical information obtained by echocardiography as well as the assessment of the intra-atrial obstruction by cardiac Doppler seem to be sufficient to make surgical decisions in patients suffering from this disease. Both are also suitable to test the result of the surgical intervention.


Assuntos
Coração Triatriado/diagnóstico por imagem , Ecocardiografia Doppler , Adulto , Cateterismo Cardíaco , Coração Triatriado/cirurgia , Humanos , Masculino
20.
Rev Esp Enferm Dig ; 80(1): 53-6, 1991 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-1931246

RESUMO

Three adult patients presented with dysphagia due to vascular compression of the esophagus. In one case, a dysphagia aortica was diagnosed. In the remaining two cases a congenital vascular anomaly--aberrant right subclavian artery and right aortic arc, respectively--was proved by arteriography. The final diagnosis was suspected after the barium meal and confirmed by computarized tomography in each case.


Assuntos
Aorta Torácica/anormalidades , Aneurisma Aórtico/complicações , Transtornos de Deglutição/etiologia , Artéria Subclávia/anormalidades , Adulto , Idoso , Feminino , Humanos , Masculino
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