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1.
Ciênc. Saúde Colet. (Impr.) ; 20(1): 75-84, jan. 2015. graf
Article in English, Portuguese | LILACS | ID: lil-733155

ABSTRACT

This study sought to verify the records on file and the number of cases of attempted suicide among children and adolescents who were attended by Emergency Care health professionals in the municipality of Matozinhos, Minas Gerais, Brazil. Documentary and descriptive research was conducted, the data for which was collected by means of an investigation of Outpatient Records from 2008 to 2010. Of the 73,000 files evaluated, those dealing with cases of attempted suicide among children and adolescents between the age of 3 and 18 years were selected. It was revealed that the health professionals, particularly physicians and nurses, fail to register the cases appropriately, invalidating information about the problem and potential prevention measures. The conclusion reached was that underreporting and the discrepancy of the diagnoses which were not duly referred to the competent agencies require rethinking and reviewing medical practices, and taking a systematic and careful look to address the individual as a complex whole.


Neste estudo procurou-se verificar o registro e o número de casos de tentativa de suicídio entre crianças e adolescentes do município de Matozinhos, Minas Gerais, Brasil, que foram atendidos pelos profissionais de saúde do Pronto-Atendimento. Trata-se de uma pesquisa documental e descritiva, cuja coleta dos dados ocorreu por meio de investigação nas Fichas Ambulatoriais, no período de 2008 a 2010. Das 73.000 fichas levantadas, selecionaram-se aquelas que tratavam de casos de tentativa de suicídio entre crianças e adolescentes do município, com idades entre três e 18 anos. Percebeu-se que os profissionais de saúde, mais especificamente os médicos e enfermeiros, não registram os casos de forma adequada, inviabilizando a informação sobre o problema e as medidas de prevenção. Concluiu-se que a subnotificação, a discrepância dos diagnósticos e o não encaminhamento aos órgãos competentes exigem repensar e rever a prática médica e dirigir um olhar sistematizado e cuidadoso para perceber o sujeito como um todo complexo.


Subject(s)
Aldehydes/chemistry , Cytochromes c/chemistry , Mitochondrial Membranes/metabolism , Oxidative Stress/drug effects , Amino Acid Sequence , Cardiolipins/chemistry , Cardiolipins/metabolism , Cytochromes c/metabolism , Electron Transport Complex IV/metabolism , Histidine/chemistry , Histidine/metabolism , Hydrogen-Ion Concentration , Lysine/chemistry , Lysine/metabolism , Molecular Sequence Data , Molecular Weight , Oxidative Stress/physiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Time Factors
2.
Journal of Forensic Medicine ; (6): 177-180, 2015.
Article in Chinese | WPRIM | ID: wpr-983982

ABSTRACT

OBJECTIVE@#To investigate the relation between injury time and the expression of cytochrome c oxidase subunit VIc (COX6C) mRNA in skeletal muscle of rat after contusion.@*METHODS@#A total of fifty-four SD rats were divided into the control group and the contusion groups (0.5, 1, 6, 12, 18, 24, 30, and 36 h after contusion), randomly. The contusion model was established by free fall drop of gravity hammer. At corresponding time point after contusion, the regular histology was examined and expression level of COX6C mRNA was tested by real-time PCR after extraction of total RNA from the tissues.@*RESULTS@#The main pathological features of 6 h after injury included edema and hemorrhage in myocytes with no inflammatory cells found. After 6 hours, the findings included myocyte degeneration and necrosis, inflammatory cells infiltration, and fibrous connective tissue proliferation in the contused zone. The expression level of COX6C mRNA was higher than that of the control group within 6 h after contusion. The expression level was lower than that of the control group from 6-36 h after contusion.@*CONCLUSION@#The level of COX6C mRNA expresses in a regular way after contusion. It may be useful for estimating wound age in combination with the results of pathological features.


Subject(s)
Animals , Rats , Contusions/metabolism , Electron Transport Complex IV/metabolism , Muscle, Skeletal/metabolism , RNA , RNA, Messenger , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Time Factors
3.
Salud pública Méx ; 56(4): 402-404, jul.-ago. 2014. tab
Article in Spanish | LILACS | ID: lil-733306

ABSTRACT

La fiebre chikungunya (CHIK) es una enfermedad viral transmitida al ser humano por el mismo vector del dengue, el mosquito Aedes. Además de fiebre y fuertes dolores articulares, produce otros síntomas como mialgias, cefalea, náuseas, cansancio y exantema. No tiene tratamiento específico; el manejo terapéutico de los pacientes se enfoca en el alivio de los síntomas. Históricamente se han reportado brotes de grandes proporciones; incluso desde 2010 se llegó a considerar como una potencial epidemia emergente. En 2013 se introdujo a las islas del Caribe y recientemente se ha reportado en el continente americano. En este trabajo se describe el primer caso confirmado de chikungunya en México, en el municipio de Tlajomulco de Zúñiga, Jalisco, en mayo de 2014, importado de la isla Antigua y Barbuda, en el Caribe, por una mujer de 39 años de edad.


Chikungunya fever (CHIK) is a viral disease transmitted to human beings by the same vector as dengue -the Aedes mosquito. Besides fever and severe pain in the joints, it produces other symptoms such as myalgias, headache, nausea, fatigue and exanthema. There is no specific treatment for it; the therapeutic management of patients focuses on symptom relief. Historically, outbreaks of large proportions have been reported; even since 2010 it was considered to be a potential emerging epidemic. In 2013 it was introduced into the islands of the Caribbean, and it has recently been reported in the American continent. This paper describes the first confirmed case of chikungunya in Mexico -in the municipality of Tlajomulco de Zúñiga, Jalisco, in May, 2014-, which was imported from the Caribbean island of Antigua and Barbuda by a 39 year-old woman.


Subject(s)
Animals , Cattle , Male , Rats , Antidotes/pharmacology , Hot Temperature , Imidazoles/toxicity , Meat , Mitochondria/metabolism , Mutagens/toxicity , Oxygen Consumption/drug effects , Ubiquinone/pharmacology , Antidotes/administration & dosage , Cooking , Diet , Electron Transport Complex II , Electron Transport Complex III/metabolism , Electron Transport Complex IV/metabolism , Electron Transport/drug effects , Food, Fortified , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Mitochondria, Liver/drug effects , Mitochondria, Liver/metabolism , Mitochondria, Muscle/drug effects , Mitochondria, Muscle/metabolism , Multienzyme Complexes/metabolism , NAD(P)H Dehydrogenase (Quinone)/metabolism , Oxidoreductases/metabolism , Rats, Wistar , Succinate Dehydrogenase/metabolism , Ubiquinone/administration & dosage
4.
West Indian med. j ; 62(1): 3-11, Jan. 2013. ilus, tab
Article in English | LILACS | ID: biblio-1045580

ABSTRACT

Cytochrome c oxidase (COX) employs electrons obtained from cytochrome c to bring about the reduction of oxygen to water. It is known that the electrons originate from the haem edge of cytochrome c and enters bovine COX at Trp-104. It is also known that Tyr-105, Glu-198 and Asp-158 of COX subunit II play roles in the enzyme's catalysis but how these roles are linked to electron transfer remain unclear. Recently, we proposed that electrons travel from the haem edge of cytochrome c to CuA, the first metal redox centre of COX, by a hydrogen/hydride ion relay using six residues. Now using a similar computer assisted approach, we investigate the extent to which this hydride/hydrogen ion mechanism is common amongst oxidases. The crystal structures of COX from P denitrificans, R sphaeroides and T thermophilus and quinol oxidase from E coli were downloaded and their binding domains analysed. As with bovine, all four oxidases had only nine amino acid residues in that region and both the sequences and three-dimensional structures were highly conserved. We propose that these residues function as a hydrogen/hydride ion relay, participating directly in electron transfer to CuA. We further suggest that this electron transfer mechanism might be a common feature in oxidases.


La citocromo c oxidasa (COX) emplea electrones obtenidos del citocromo c para producir la reducción del oxígeno a agua. Se sabe que los electrones originan a partir del hemo del citocromo c, y entran en la COX bovina en Trp-104. También se conoce que Tyr-105, Glu-198 y Asp-158 de la subunidad II de COX, desempeñan papeles en la catálisis de la enzima, pero no hay todavía claridad en cuanto a cómo estos papeles se hallan vinculados con la transferencia de electrones. Recientemente, sugerimos que los electrones viajan del borde del hemo del citocromo c al CuA, el primer centro metálico de reacción redox de la COX, por un relé iónico hidrógeno-hidruro, usando seis residuos. Ahora, usando un enfoque similar computarizado, investigamos hasta que punto este mecanismo de iones hidrógeno/hidruro es común entre las oxidasas. Se bajaron y analizaron los dominios de unión de las estructuras cristalinas de la COX de P denitrificans, R sphaeroides, y T thermophilus, y de la quinol oxidasa de la E coli. Como en el caso de la bovina, las cuatro oxidasas tenían sólo nueve residuos de aminoácido en esa región, y tanto las secuencias como las estructuras tridimensionales presentaban un alto grado de conservación. Proponemos que estos residuos funcionan como un relé iónico hidrógeno-hidruro, participando directamente en una transferencia de electrones al CuA. Asimismo, sugerimos que este mecanismo de transferencia de electrones podría ser un rasgo común de las oxidasas.


Subject(s)
Animals , Cattle , Electron Transport Complex IV/metabolism , Cytochromes c/metabolism , Heme/chemistry , Hydrogen/metabolism , Oxidation-Reduction , Paracoccus denitrificans/enzymology , Protons , Rhodobacter sphaeroides/enzymology , Amino Acid Sequence , Thermus thermophilus/enzymology , Escherichia coli/enzymology
5.
West Indian med. j ; 58(6): 499-505, Dec. 2009. ilus
Article in English | LILACS | ID: lil-672532

ABSTRACT

Evidence suggests that when ferrocytochrome c (the substrate) reduces cytochrome c oxidase (COX), electrons from the former enter the latter via Trp-104. What is still to be determined is the method by which electrons are transferred from ferrocytochrome c to Trp-104 and the method by which electrons arriving at Trp-104 are moved on to cua, the first of the enzyme's four redox centres to be reduced. To shed light on this process, we used the computer to create and analyse an enzyme-substrate complex formed from the published structure of the two proteins. It was found that the front haem edge of ferrocytochrome c was in close proximity to Trp-104 of COX and that inclusive of Trp-104, only nine amino acid residues from COX lie along a broad channel stretching from Trp-104 to the enzyme's CuA centre. Six of the nine residues, Trp-104, Tyr-105, His-102 Trp-106, Asp-158 and Glu-198, had the ideal chemical properties and were properly aligned to facilitate electron transfer. Here we propose that the reduction of Trp-104 and the subsequent reduction of CuA occur by a hydride/hydrogen ion relay system similar to that seen at the active site of chymotrypsin.


La evidencia sugiere que cuando el ferrocitocromo C (el sustrato) reduce el citocromo c oxidasa (COX), los electrones del primero entran a este último vía Trp-104. Lo que queda aún por determinar es el método por el cual los electrones son transferidos del ferrocitocromo c al Trp-104, así como el método mediante el cual los electrones que llegan al Trp-104 son trasladados al cua, el primero de los cuatro centros de reducción-oxidación (redox) de la enzima a ser reducidos. A fin de arrojar luz sobre este proceso, usamos la computadora para crear y analizar un complejo de sustrato enzimático formado a partir de la estructura publicada de las dos proteínas. Se halló que el borde frontal del hemo del ferrocitocromo c estaba muy cercano al Trp-104 del COX, incluyendo el Trp-104. Sólo nueve residuos de aminoácidos de COX se encuentran a lo largo de un ancho canal que se extiende desde Trp-104 hasta el centro CuA de la enzima. Seis de los nueve residuos, Trp-104, Tyr-105, His-102 Trp-106, Asp-158 y Glu-198, poseían las propiedades químicas ideales y estaban alineados adecuadamente para facilitar la transferencia de electrones. En este trabajo proponemos que la reducción de Trp-104 y la subsiguiente reducción de CuA ocurre mediante un sistema de relé iónico hidrógeno-hidruro, similar al que se observa en el sitio activo de la quimotripsina.


Subject(s)
Humans , Electron Transport Complex IV/metabolism , Chymotrypsin/metabolism , Computer Simulation , Oxidation-Reduction
6.
West Indian med. j ; 58(5): 422-427, Nov. 2009. ilus, tab
Article in English | LILACS | ID: lil-672514

ABSTRACT

Aluminium has a unique combination of physical and chemical properties which has enabled man to put this metal to very wide and varied use. However, prolonged exposure to aluminium ions may lead to adverse health effects. In this study, we evaluated the effects of dietary aluminium on the protein composition and the intrinsic activity of cytochrome oxidase (COX) for brain mitochondria. New Zealand white rabbits were maintained on a diet of commercial rabbit pellets and distilled water for a period of 12 weeks. For the experimental group, AlCl3, 330mg/kg/L was added to the drinking water. When compared to the control, mitochondria isolated from the brains of the AlCl3 fed rabbits showed no change in Km but an approximate 35% decrease in both the low and high affinity Vmax values. Also, whereas the protein composition of the mitochondria from both sources appeared to be normal, isolation of highly purified COX proved to be difficult and for the AICI3 fed rabbits, a number of the enzyme's low molecular weight subunits were absent. These results appear to confirm a relationship between long term aluminium consumption and low brain COX activity; they further suggest that an altered COX structure may be the cause of the low enzymic activity.


El aluminio posee una combinación única de las propiedades físicas y químicas que ha permitido al ser humano hacer un uso amplio y variado de este metal. Sin embargo, un número de estudios recientes, sugiere que la exposición prolongada a los iones de aluminio puede tener efectos nocivos sobre la salud. En el presente estudio, evaluamos los efectos del aluminio dietético sobre la composición proteínica y la actividad intrínseca de la oxidasa citocrómica (COX) para la mitocondria cerebral. Conejos blancos de Nueva Zelanda, fueron mantenidos con una dieta de alimento para conejos y agua destilada por un período de 12 semanas. Para el grupo experimental AlCl3, 330mg/kg/L fueron añadidos al agua potable. En comparación con el grupo de control, las mitocondrias aisladas de los cerebros de los conejos alimentados con AlCl3 no mostraron cambios en Km pero hubo una disminución de aproximadamente 35% tanto en los valores Vmax de baja y alta afinidad. Por otro lado, mientras que la composición proteica de las mitocondrias de ambas fuentes parecía ser normal, resultó difícil aislar el COX altamente purificado y un número de enzimas de subunidades de bajo peso molecular MMMM estuvieron ausentes. Estos resultados parecen confirmar una relación entre el consumo de aluminio a largo plazo y la baja actividad del COX del cerebro. Asimismo, sugieren que una alteración de la estructura del COX puede ser la causa de una baja actividad enzimática.


Subject(s)
Animals , Rabbits , Aluminum Compounds/toxicity , Brain/metabolism , Chlorides/toxicity , Electron Transport Complex IV/drug effects , Electron Transport Complex IV/metabolism , Mitochondria/enzymology , Administration, Oral , Aluminum Compounds/administration & dosage , Astringents/administration & dosage , Astringents/toxicity , Brain Chemistry/drug effects , Brain/enzymology , Chlorides/administration & dosage , Mitochondria/chemistry
7.
Journal of Korean Medical Science ; : 103-112, 2002.
Article in English | WPRIM | ID: wpr-87470

ABSTRACT

Mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episode (MELAS) and myoclonic epilepsy and raggedred fibers (MERRF) are rare disorders caused by point mutation of the tRNA gene of the mitochondrial genome. To understand the pathogenetic mechanism of MELAS and MERRF, we studied four patients. Serially sectioned frozen muscle specimens with a battery of histochemical stains were reviewed under light microscope and ultrastructural changes were observed under electron microscope. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was performed and the tRNA genes were sequenced to confirm mutations. In two patients with MELAS, strongly succinyl dehydrogenase positive blood vessels (SSVs) and many cytochrome oxidase (COX) positive raggedred fibers (RRFs) were observed, and A3243G mutations were found from the muscle samples. In two patients with MERRF, neither SSV nor COX positive RRFs were seen and A8344G mutations were found from both muscle and blood samples. In the two MERRF families, the identical mutation was observed among family members. The failure to detect the mutation in blood samples of the MELAS suggests a low mutant load in blood cells. The histochemical methods including COX stain are useful for the confirmation and differentiation of mitochondrial diseases. Also, molecular biological study using muscle sample seems essential for the confirmation of the mtDNA mutation.


Subject(s)
Adolescent , Adult , Female , Humans , Male , Electron Transport Complex IV/metabolism , Korea , MELAS Syndrome/genetics , MERRF Syndrome/genetics , Pedigree , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , RNA, Transfer , Sequence Analysis, DNA
9.
Indian J Exp Biol ; 1999 Nov; 37(11): 1139-41
Article in English | IMSEAR | ID: sea-59349

ABSTRACT

Cytochrome c oxidase was purified from control and CCl4 treated rats and its kinetic properties were studied. The activity of the enzyme was inhibited by 51% in CCl4 (4 g per kg body weight for 24 hr) treated rats. Studies on the kinetic properties showed that the K(m) of the enzyme increased by 60% while Vmax decreased by 44% in CCl4 treated rats compared to controls. The content of cytochrome aa3 was decreased by 34% while cytochrome b and c were not affected by CCl4 treatment. Phosphatidylcholine, phosphatidylethanolamine and cardiolipin were decreased significantly by 40%, 49% and 60% respectively in CCl4 treated rats. A decrease in the cytochrome aa3 content and a change in the lipid environment of the membrane are probably responsible for a decreased rate of electron transfer from cytochrome c to oxygen.


Subject(s)
Animals , Carbon Tetrachloride/toxicity , Electron Transport Complex IV/metabolism , Kinetics , Male , Mitochondria, Liver/drug effects , Rats , Rats, Wistar
10.
Yonsei Medical Journal ; : 69-75, 1999.
Article in English | WPRIM | ID: wpr-63763

ABSTRACT

The purpose of this study were 1) to determine the earliest pathological changes of germanium dioxide (GeO2)-induced myopathy; 2) to determine the pathomechanism of GeO2-induced myopathy; and 3) to determine the minimal dose of GeO2 to induce myopathy in rats. One hundred and twenty five male and female Sprague-Dawley rats, each weighing about 150 gm, were divided into seven groups according to daily doses of GeO2. Within each group, histopathological studies were done at 4, 8, 16, and 24 weeks of GeO2 administration. Characteristic mitochondrial myopathy was induced in the groups treated daily with 10 mg/kg of GeO2 or more. In conclusion, the results were as follows: 1) The earliest pathological change on electron microscope was the abnormalities of mitochondrial shape, size and increased number of mitochondria; 2) The earliest pathological change on light microscope was the presence of ragged red fibers which showed enhanced subsarcolemmal succinate dehydrogenase and cytochrome c oxidase reactivity; 3) GeO2 seemed to affect the mitochondrial oxidative metabolism of muscle fibers; 4) GeO2 could induce mitochondrial myopathy with 10 mg/kg of GeO2 for 4 weeks or less duration in rats.


Subject(s)
Female , Male , Rats , Animals , Electron Transport Complex IV/metabolism , Germanium/toxicity , Histocytochemistry , Mitochondrial Myopathies/pathology , Mitochondrial Myopathies/enzymology , Mitochondrial Myopathies/chemically induced , Muscles/ultrastructure , Muscles/enzymology , Rats, Sprague-Dawley , Succinate Dehydrogenase/metabolism
11.
Medicina (B.Aires) ; 58(4): 357-60, 1998.
Article in Spanish | LILACS | ID: lil-217514

ABSTRACT

El óxido nítrico (ON) sintetizado de manera constitutiva en una célula generadora, actúa sobre otra célula efectora como regulador fisiológico del tono vascular, de la inhibición planquetaria o de la interación neurona-neurona. En forma contraría, la liberación inducida de grandes cantidades de ON por períodos largos transforma al ON de un mediador fisiológico en una molécula citostática y citotóxica. La presencia de ON sintetasa en la mitocondria sugiere que la producción fisiológica de ON en pequeñas cantidades estaría relacionada con la regulación de la respiración celular a través de la inhibición de la citocromo oxidasa. La exposición celular a ON por períodos prolongados da como resultado una inhibición irreversible de la respiración celular que es independiente de la formación generalizada de superóxido o de peroxinitrito. La inhibición de la respiración celular es persistente excepto si se estudia el complejo IV aislado, si se bloquea el complejo I o si se pone glutatión. De esta manera nuestra hipótese es que la inhibición del complejo IV es un efecto fisiológico normal, dependiente de las concentraciones de ON. Si se expone las células a ON por períodos largos, se nitrosilan tioles en el complejo I y a medida que se están nitrosilando, el glutatión transnitrosila y limpia el complejo I hasta que el glutation cae a un nivel crítico. En estas condiciones se produce la inhibición irreversible de la respiración y posiblemente, este sea el camino que transforma al ON de un mediador fisiológico en una molécula con efectos patológicos. Asi mismo, creemos que la nitrosilación de tioles y la transnitrosilación por el glutatión constituyen un mecanismo crítico de la prevención del stress oxidativo.


Subject(s)
Humans , Cell Respiration/physiology , Nitric Oxide Synthase/physiology , Nitric Oxide/physiology , Oxygen Consumption/physiology , Cell Respiration , Electron Transport Complex IV/metabolism , Nitric Oxide , Oxidative Stress/physiology
12.
Indian J Biochem Biophys ; 1997 Jun; 34(3): 296-301
Article in English | IMSEAR | ID: sea-27103

ABSTRACT

The effect of galactosamine on liver mitochondrial functions was studied in vivo in rats at 12hr, 24hr and 36hr after the administration of the drug. State 3 respiration decreased significantly with both NAD+ linked and FAD linked substrates. Respiratory control ratio, an index of membrane integrity and P/O ratio which is a measure of phosphorylation efficiency decreased significantly. There was a significant decrease in the activities of NADH dehydrogenase, succinate dehydrogenase and cytochrome oxidase. A significant decrease was also seen on membrane potential, cytochrome aa3, cytochrome b, cytochrome c and on phospholipids of mitochondria. The observed mitochondrial dysfunctions were related to increased lipid peroxidation, which could cause loss of membrane integrity and a decreased rate of phosphorylation. It is proposed that increased lipid peroxidation was responsible for the inhibition on both oxidation and phosphorylation in mitochondria in galactosamine treated rats.


Subject(s)
Animals , Cell Respiration/drug effects , Cytochromes/analysis , Electron Transport/drug effects , Electron Transport Complex IV/metabolism , Galactosamine/pharmacology , Lipid Peroxides/analysis , Lipids/analysis , Mitochondria, Liver/drug effects , NADH Dehydrogenase/metabolism , Phosphorylation , Rats , Succinate Dehydrogenase/metabolism
13.
Indian J Biochem Biophys ; 1996 Jun; 33(3): 218-22
Article in English | IMSEAR | ID: sea-27312

ABSTRACT

Treatment of bovine pulmonary artery smooth muscle mitochondria with H2O2 stimulated oxidation of GSH and NAD(P)H along with an increase in Ca2+ release. Addition of oxaloacetate to mitochondrial suspension stimulated Ca2+ release and oxidation of NAD(P)H while GSH level remained unchanged. Subsequently, addition of beta-hydroxybutyrate which reduced mitochondrial pyridine nucleotides caused reuptake of the released Ca2+ without causing appreciable alteration of GSH level. Treatment of the mitochondria with 1,3-bis(2-dichloroethyl)-1-nitrosourea (BCNU), an inhibitor of glutathione reductase, significantly decreased GSH level without producing discernible change in Ca2+ release and NAD(P)H oxidation.


Subject(s)
Animals , Calcium/metabolism , Carmustine/pharmacology , Cattle , Electron Transport Complex IV/metabolism , Glutathione/metabolism , Hydrogen Peroxide/pharmacology , Kinetics , Mitochondria/drug effects , Muscle, Smooth, Vascular/metabolism , NAD/metabolism , NADP/metabolism , Oxaloacetates/pharmacology , Oxaloacetates , Oxidation-Reduction , Pulmonary Artery/metabolism
14.
Indian J Biochem Biophys ; 1992 Oct; 29(5): 425-7
Article in English | IMSEAR | ID: sea-26879

ABSTRACT

The redox state of cytochrome alpha 3 during in situ respiration of leaves of 20-day-old rice seedlings was assessed by in vivo aerobic assay of nitrate reductase, after 1 min exposure to carbon monoxide. Different stress treatments like water and salt stresses, disintegration of leaf tissues and darkness modified the redox state of cytochrome c oxidase. The dark treatment altered the redox state of cytochrome oxidase from reduced to the oxidized state, as judged by its reaction with CO in CO-sensitive rice cultivar. The water and salt stresses as well as the disintegration of leaf tissue on the contrary altered cytochrome oxidase from the oxidized to its reduced state in CO-insensitive cultivars; probably by changing the cellular integrity, turgidity and structure of mitochondrial membrane, and also due to decreased mitochondrial energization.


Subject(s)
Aerobiosis , Anaerobiosis , Carbon Monoxide/pharmacology , Darkness , Electron Transport Complex IV/metabolism , Kinetics , Nitrate Reductase , Nitrate Reductases/metabolism , Oryza/enzymology , Osmolar Concentration , Oxidation-Reduction , Sodium Chloride/pharmacology , Water
15.
Arch. latinoam. nutr ; 41(1): 62-71, mar. 1991. tab
Article in Spanish | LILACS | ID: lil-108033

ABSTRACT

Ratas hembras vírgenes, cepa Wistar, se dividieron en tres grupos de 18 animales cada uno. Un grupo fue alimentado con una dieta que aporta (45% de las calorías como grasa(45g%), otro se alimentó con una dieta baja en grasa (15%), y el tercero sirvió como testigo. Para ambos niveles, alto y bajo, la relación ácidos grasos poliinsaturados a saturados (P/S) se ajustó a 2.0 sustituyendo los ácidos grasos saturados por aceite de maíz (Omega 6). A un grupo control se le ofreció una dieta preparada con 30% (30g%) de las calorías grasas, con una relación P/S de 1.0. Cada grupo consumió sólo una de la dietas desde antes, y durante la preñez. A los 20 días de edad gestacional todas as ratas fueron sacrificadas y se les extrajeron los fetos, placentes, y hígado materno, y se aislaron las membranas mitocondriales de palcentes e hígado. Luego se analizó la composición de los ácidos grasos de los fosfolípidos mitocondriales y la actividad de citocromo-c-oxidasa en la membrana interna, y de NADH citocromo o reductasa insensible a la totenona en la membrana mitocondrial externa. La citocromo-c-oxidasa de vio activada por el aumento de los Omega 6 en los fosfolípidos, originado por la dieta de 45g% P/S2. La acticiad de NADH citocromo-c-reductasa se redujo en el grupo que recibió 15 g%, P/S2, y en ese grupo no se alteró la actividad de citocromo-c-oxidasa en relación al grupo control. El peso fetal del grupo de madrs que consumió 45g% P/S1, experimentó un significativo aumento ponderal en relación a los otros dos grupos. Este estudio indica que dietas análogas en el contenido e grasa y poliinsaturados Omega 6 a a los potencialmente consumidos por humanos, pueden inducir cambios en los constituyentes estructurales de las membranas y en las funciones de las proteínas lípido-dependiente de membrana. Por lo tanto, se postula que un aumento de los poliinsaturados 6 en los fosfolípidos de la membrana mitocondrial favoreció la función celular de los órganos estudiados, reflejándose en el estímulo del crecimiento uterino fetal


Subject(s)
Pregnancy , Rats , Animals , Female , Diet , Fatty Acids, Unsaturated/pharmacology , Mitochondria, Liver/ultrastructure , Placenta/ultrastructure , Electron Transport Complex IV/metabolism , Mitochondria, Liver/enzymology , NADH Dehydrogenase/metabolism , Phospholipids/chemistry , Placenta/enzymology , Rats, Inbred Strains , Weight Gain
16.
Article in English | LILACS | ID: lil-113720

ABSTRACT

En el presente trabajo se describen los efectos de la restitución de corticosterona a ratas con diabetes inducida por estreptozotocina sobre a) la función de mitocondrias enteras de hígado y b) sobre las actividades enzimáticas de la 3- hidroxibutirato deshidrogenasa (HBD), citocromo c oxidasa (Cox) y succinato deshidrogenasa (SD) de mitocondrias que sufrieron ruptura por método físico. La función mitocondrial fue analizadas por la respiración y por el comportamiento oscilatorio osmótico de esas organelas. La respiración se midió por método polarográfico y se midieron el estado 3 de la respiración activa (S3) y el control respiratorio (CR) usando los siguientes sustratos: 3-hidroxibutirato, malato-glutamato y succinato. El comportamiento oscilatorio osmótico se midió usando como parámetro comparativo los coeficientes de amortiguación (CA), que son los cocientes de las amplitudes de dos picos o valles consecutivos obtenidos en el registro espectrofotométrico de dicho fenómeno. Se dispusieron un grupo de ratas normales no diabéticas (N) y los siguientes grupos de ratas diabéticas: controles (D), adrenalectomizadas (D + ADX) y adrenalectomizadas con restitución de corticosterona (D + ADX + C). Los resultados de la respiración mitocondrial mostraron que los valores medios de S3 y CR disminuyeron con los tres sustratos en el grupo D + ADX + C comparado con el grupo D + ADX (p < 0,001). Este grupo demostró, a su vez, un aumento significativo de los valores medios de S3 y CR de respiración con respecto al del grupo D. El comportamiento oscilatorio de mitocondrias enteras de hígado del grupo D + ADX + C demostró un significativo aumento de los CA de picos y valles comparado con los del grupo D + ADX. Los valores de CA del último grupo no fueron significativamente diferentes de los del grupo N. El comportamiento de las actividades enzimáticas de mitocondrias fraccionadas fueron diferentes para cada enzima según los diferentes tratamientos en los grupos de ratas diabéticas. En el grupo D + ADX + C el valor medio de la actividad HBD disminuyó significativamente, el de la Cox aumentó (p < 0,02) y el de la SD no mostró variación alguna con respecto a los correspondientes valores medidos de esas enzimas en el grupo D + ADX. Asimismo, el valor medio de la actividad HBD en este último grupo fue similar al del grupo N y el de Cox fue menor (p < 0,001) que el del grupo D. Se concluye que la corticosterona tiene un significativo efecto diabetogénico sobre la función bioquími


Subject(s)
Animals , Female , Rats , Corticosterone/pharmacology , Electron Transport Complex IV/metabolism , Hydroxybutyrate Dehydrogenase/metabolism , Mitochondria, Liver/physiology , Succinate Dehydrogenase/metabolism , Adrenalectomy , Oxygen Consumption , Corticosterone/administration & dosage , Diabetes Mellitus, Experimental , Mitochondria, Liver/enzymology
17.
Indian J Exp Biol ; 1990 Jun; 28(6): 572-4
Article in English | IMSEAR | ID: sea-55684

ABSTRACT

The activity levels of succinate dehydrogenase (SDH), malate dehydrogenase (MDH) and cytochrome-C-oxidase showed a decrement whereas lactate dehydrogenase (LDH) evinced maximum activity during first 3 days of denervation. Under the impact of cathodal polarity treatment an elevation in the activity levels of these 4 enzymes was relatively more potent when compared to anodal polarity treatment. The role of polarity treatment in the regulation of these oxidative enzymes was discussed.


Subject(s)
Animals , Bufonidae , Electron Transport Complex IV/metabolism , Electrophysiology , L-Lactate Dehydrogenase/metabolism , Malate Dehydrogenase/metabolism , Muscle Denervation , Muscles/enzymology , Oxidation-Reduction , Succinate Dehydrogenase/metabolism
18.
Arq. neuropsiquiatr ; 48(1): 32-43, mar. 1990. ilus, tab
Article in English | LILACS | ID: lil-83214

ABSTRACT

Os autores descrevem uma família de raça negra (mäe e três filhos) com miopatia mitocondrial. Duas irmäs tinham acidose láctica concomitante e epilepsia mioclônica. Outros achados observados nos membros mais afetados foram demência, ataxia, fraqueza muscular e neuropatia sensitiva. A mäe era assintomática. Um filho sofreu acidente vascular cerebral isquêmico envolvendo a regiäo temporal direita. Todos os membros da família estudados eram hipertensos. EEG mostrou resposta fotomioclônica na paciente probanda. Biópsia muscular mostrou fibers e mitocôndrias anormais ao estudo de microscopia eletrônica. Análise bioquímica mostrou um defeito no citocromo C oxidase nas mitocôndrias extraídas do músculo esquelético de uma paciente afetada. Aspectos clínicos e genéticos sobre as encefalomiopatias mitocondriais säo discutidos


Subject(s)
Adult , Middle Aged , Humans , Male , Female , Muscular Diseases/genetics , Mitochondria, Muscle/ultrastructure , Acidosis, Lactic/complications , Muscular Diseases/complications , Muscular Diseases/diagnosis , Electroencephalography , Electron Transport Complex IV/metabolism , Epilepsies, Myoclonic/complications , Mitochondria, Muscle/metabolism , Muscles/pathology , Pedigree
19.
Acta physiol. pharmacol. latinoam ; 40(4): 373-80, 1990. ilus
Article in English | LILACS | ID: lil-95072

ABSTRACT

Las enzimas citrocromo-c-oxidasa y P-450 fueron mediadas en cortezas adrenales de ratas macho adultas en cuatro condiciones experimentales: G1, controles; G2, castrados; G3, castrados y tratados con testosterona y G4, castrados y tratados con testosterona y dexametasona. Con la citocromo-c-oxidasa no se observaron diferencias significativas entre G1, G2 y G4. La máxima actividad se encontró en el grupo G3, el cual difiere significativamente del resto de los grupos. Con citocromo P-450 no se encontraron diferencias entre G1 y G3. Sin embargo, se encontraron diferencias significativas entre G1 y G4. Estos estudios proveen nuevas evidencias con referencia a la interacción de la corteza adrenal y las gónadas en relación con la actividad esteroidogénica y respiratoria


Subject(s)
Rats , Animals , Male , Adrenal Cortex/metabolism , Castration , Cytochrome P-450 Enzyme System/metabolism , Dexamethasone/pharmacology , Electron Transport Complex IV/metabolism , Testosterone/pharmacology , Adrenal Cortex/enzymology , Rats, Wistar
20.
Braz. j. med. biol. res ; 23(5): 375-93, 1990. ilus
Article in English | LILACS | ID: lil-91926

ABSTRACT

1. The topographic organization of the cortical visual areas in the Cebus monkey and their anatomical connections support the subdivision of the visuaol pathways into ventral and dorsal streams of visual information provessing. 2. We propose that the dorsal stream, as defined by Ungerleider and Mishkin (In: Ingle DJ, Goodale MA and Mansfield RJW (Editors), Analysis of Visual Behavior, MIT Press, Boston, 1982), be subdivided into dorsolateral and dorsomedial streams, which are concerned with different aspects of the processing of motion and spatial perception. 3. The data support the hypothesis of concurrent, modular processing of visual attributes in cortical visual areas in the different streams, and highlight some features of the visual field representation in each area which may reflect functional specialization of these streams. 4. The visual topography is locally disrupted in some cortical areas by the existence of functionally different modules, However, a global visuotopic organization is preserved in most areas. 5. The visuotopic organization may provide the address of space coordinates to integrate information concerning the same retinotopic across different visual areas


Subject(s)
Animals , Visual Cortex/anatomy & histology , Visual Fields , Visual Pathways/anatomy & histology , Cebus/anatomy & histology , Electron Transport Complex IV/metabolism , Histocytochemistry , Visual Cortex/enzymology
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