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2.
Acta Neurol Scand ; 111(5): 329-32, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15819713

RESUMO

We have investigated the dynamics of cytochrome c oxidase (COX) activity in the cerebrospinal fluid (CSF) and the erythrocyte haemolysate (EH) in 85 patients suffering from brain infarction (BI), reversible (RIA), or transient (TIA) ischemic attack from the perspective of mitochondrial affection in ischemia. In all patients, the COX activity was decreased in the CSF, especially within the first two days, indicating an acute inactivation or modification of mitochondrial proteins, probably mediated by free radicals. The gradual elevation of COX activity until the seventh day suggested that these changes may be reversible. The increase in the COX activity was established in the EH, with the highest values found in the BI, somewhat lower in the RIA, and the lowest in the TIA group, respectively. This could indicate a systemic compensatory response to an acute ischemia. Thus, COX activity in the CSF and EH in acute ischemia could be an indicator of brain metabolic dysfunction.


Assuntos
Isquemia Encefálica/enzimologia , Complexo IV da Cadeia de Transporte de Elétrons/líquido cefalorraquidiano , Complexo IV da Cadeia de Transporte de Elétrons/farmacologia , Acidente Vascular Cerebral/enzimologia , Doença Aguda , Idoso , Líquido Cefalorraquidiano/enzimologia , Eritrócitos/enzimologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Vojnosanit Pregl ; 58(3): 237-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11548547

RESUMO

The etiology of neuronal death in neurodegenerative diseases, including Huntington's disease (HD), is still unknown. There could be a complex interplay between altered energy metabolism, excitotoxicity and oxidative stress. Unilateral administration of quinilonic acid (QA), NMDA agonist, in rat striatum in a single dose of 150 nM was used as a model of HD. The other two groups of animals were pretreated immediately before QA application with nerve growth factor (NGF) and fibroblast growth factor (FGF), respectively. Control group was treated with 0.9% NaCl in the same manner. Content of total glutathione was not altered in the striatum and hippocampus of QA-treated animals, as well as in the groups pretreated with neurotrophic factors (NF), compared to controls. Content of reduced glutathione, a key antioxidant, was mutually depleted in the striatum and hippocampus of each experimental group. The reduced/total glutathione ratio was decreased in the QA-treated animals, but nearby or over the controls in each structure of the NF-treated groups. These results support the hypothesis that oxygen-free radicals contribute to the excitotoxic neuronal injury, and also that NF could be the potential neuroprotective agents in HD. Moreover, activity of cytochrome c oxidase, the last component in the mitochondrial respiratory chain, was mutually increased in each structure of QA-treated animals. This increase was less pronounced in the NF-treated groups. Striatal lesions led to the loss of tonic inhibitory inputs to the globus pallidus with consequent increase in the activity of GABAergic efferent pallidal neurons, suggesting that NF could functionally repair the altered striopallidal pathway.


Assuntos
Corpo Estriado/metabolismo , Hipocampo/metabolismo , Doença de Huntington/metabolismo , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético , Fatores de Crescimento de Fibroblastos/farmacologia , Fatores de Crescimento de Fibroblastos/fisiologia , Glutationa/metabolismo , Doença de Huntington/induzido quimicamente , Fator de Crescimento Neural/farmacologia , Fator de Crescimento Neural/fisiologia , Ácido Quinolínico , Ratos , Ratos Wistar
4.
Vojnosanit Pregl ; 58(5): 463-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11769409

RESUMO

General reaction of an organism (survival, body temperature, hematocrit, glycemia) was followed in Mongolian gerbils subjected to isolated head injury (brain ischemia--LD5), to peripheral injury (ischemia of both hind limbs--LD20), and to combined injury (head injury + peripheral injury). In the early period (1 hour) after the injury, parameters of oxidative stress were followed in the brain cortex (superoxide anion, index of lipid peroxidation, activity of superoxide dismutase and glutathione reductase). Obtained results indicate that the combined peripheral and central injury of low lethality leads to the worsening of general response of the organism with high lethality of experimental animals (LD80). Likewise, the increased cortical production of superoxide anion and index of lipid peroxidation, as well as the disturbances of antioxidative enzymes activity suggest on an important role of brain oxidative stress in the development of the syndrome of mutual aggravation in animals subjected to combined injury.


Assuntos
Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Traumatismo Múltiplo/metabolismo , Estresse Oxidativo , Animais , Temperatura Corporal , Isquemia Encefálica/metabolismo , Feminino , Gerbillinae , Glutationa Redutase/metabolismo , Hematócrito , Membro Posterior/irrigação sanguínea , Isquemia/metabolismo , Peroxidação de Lipídeos , Masculino , Traumatismo Múltiplo/fisiopatologia , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
5.
Srp Arh Celok Lek ; 129(11-12): 300-3, 2001.
Artigo em Sérvio | MEDLINE | ID: mdl-11928615

RESUMO

Brain abscess is a rare, extremely aggressive lethal infection. It is especially important in case of otogenic abscesses. It is known that the problem of otitis existed already thousands of years before Christ, and it is still a current problem. Otogenic brain abscess is the most common otogenic complication encompassing 40-80% of all brain abscesses in adults. In 50-80% of these cases COM (chronic otitis media) with cholesteatoma is found. In the last 20 years CT is of the first rank in diagnosis. Brain abscess can be treated conservatively and surgically; but the ear has to be treated operatively. In this article we present an interesting case from our practice, a double abscess of the cerebellum of otogenic origin, which was successfully treated by simultaneous approach of neurosurgeon and otosurgeon.


Assuntos
Abscesso Encefálico/diagnóstico , Doenças Cerebelares/diagnóstico , Otite Média Supurativa/complicações , Abscesso Encefálico/etiologia , Abscesso Encefálico/cirurgia , Doenças Cerebelares/etiologia , Doenças Cerebelares/cirurgia , Doença Crônica , Feminino , Humanos , Pessoa de Meia-Idade
6.
Vojnosanit Pregl ; 57(3): 265-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11039305

RESUMO

Treatment of Wistar rats with aluminum chloride causes astroglial and neuronal cell damage in the selective brain regions of association cortex and hippocampus, seen in patients with Alzheimer's disease. Adult Wistar rats were treated with unilateral intrahippocampal injection of AlCl3 in one single dose of 3.7 g/kg b.w. Control group of animals was treated with 0.9% saline solution likewise. Animals were sacrificed by decapitation seven days after the treatment. Activity of cytochrome C oxidase (COX) and total glutathione content were measured in the ipsi- and contralateral hippocampus and forebrain cortex. Activity of COX was mutually decreased in the hippocampus (ipsi- 30%, contra- 34%), as well as in the forebrain cortex (ipsi- 44%, contra- 47%), compared to controls. These decrease could indicate a deficiency in reducing equivalents with concomitant altered proton gradient and function of electron transport chain, as well as decreased ATP synthesis. Content of glutathione, a clue antioxidative factor, was decreased for about 50% in all examined structures, primary suggesting an impaired regeneration of reduced glutathione. Such distribution of diminished antioxidative defense could be the consequence of the specific brain distribution of transferrin receptors, which was also a main protein carrier for Al. Furthermore, at the cellular level Al could impede glycolysis with consequent decreased production of reducing equivalents which were necessary for glutathione synthesis/reduction, as well as for proton gradient and functionality of electron-transport chain.


Assuntos
Compostos de Alumínio/toxicidade , Doença de Alzheimer/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cloretos/toxicidade , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glutationa/metabolismo , Cloreto de Alumínio , Animais , Hipocampo/metabolismo , Prosencéfalo/metabolismo , Ratos , Ratos Wistar
7.
Vojnosanit Pregl ; 57(3): 257-63, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11039304

RESUMO

1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism is one of the most useful models for the study of that disease. It has been suggested that MPTP-induced neurotoxicity may involve the production of reactive oxygen species. MPTP was applied intracerebrally, unilaterally, in the striatum in single dose of 0.09 g/kg b.w. The second group was treated both with MPTP and nerve growth factor (NGF) in dose of 7 ng/ml. NGF was applied immediately after the neurotoxin. Control group was treated with 0.9% saline solution in the same manner. Animals were decapitated 7 days after the treatment. In the group treated with MPTP, the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) was decreased in ipsilateral thalamus, compared to control values as well as to the contralateral thalamus. In the same structures superoxide anion production was increased, compared to controls. Following the application of both MPTP and NGF, the activity of SOD and GSH-Px remained on control values, while the superoxide anion content was decreased, compared to controls. These results indicate a temporal and spatial propagation of oxidative stress and spread protective effects of NGF on the thalamus, the structure that is distant, but very tightly connected with striatum, the place of direct neurotoxic damage.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Fator de Crescimento Neural/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transtornos Parkinsonianos/metabolismo , Tálamo/metabolismo , Animais , Glutationa Peroxidase/metabolismo , Humanos , Transtornos Parkinsonianos/induzido quimicamente , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
9.
Vojnosanit Pregl ; 57(4): 375-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11521460

RESUMO

Cerebral ischemia could be observed as acute metabolic crisis, when oxygen and glucose supply is compromised and synthesis of energy is insufficient. Apart from the excitotoxicity, increased production of reactive oxygen species with consequent lipid peroxidation is also included in neuronal cell damage. Furthermore, these toxic compounds could also be produced during the process of secondary inflammation of ischemic tissue. In the early stage of ischemia, as a systemic response to acute stress, there is an increase in glucose level in cerebrospinal fluid (CSF) and peripheral blood. According to the metabolic crisis and acidosis in ischemic brain tissue we investigated index of lipid peroxidation (ILP) and glucose utilization (IGU) in CSF of 53 patients of both sexes, aged 55-70 years with cerebral infarction. Control group comprised 15 patients with sudden onset of motor deficit subjected to diagnostic lumbar radiculography and suspected on discal genesis. ILP in CSF, as the indicator and sequela of neuronal cell membranes damage, was two fold increased in the acute period of cerebral infarction and maximal values (3.5 times) were noticed 24 hours after the ischemic episode compared to controls. Besides the increase in glucose concentration in peripheral blood and CSF of patients with cerebral infarction, IGU was decreased (37%) with minimal values (32%) 24 hours after the ischemia. These changes indicate that glucose is available but cells are incapable to metabolize it. We concluded that ILP and IGU in CSF of patients with cerebral infarction could be indicators of metabolic dysfunction and neuronal cell damage. Also, these results suggest the significance of polyvalent therapy including antioxidative and antiinflammatory agents in acute phase of cerebral ischemia.


Assuntos
Infarto Cerebral/líquido cefalorraquidiano , Glucose/líquido cefalorraquidiano , Peroxidação de Lipídeos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Vojnosanit Pregl ; 56(2): 113-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10437415

RESUMO

Experimental parkinsonism was induced in adult Wistar rats by selective nigrostriatal neurotoxine, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in a single dose of 0.09 g/kg, by unilateral intrastriatal application using stereotaxic instrument. Control group included rats treated with 0.9% saline solution in the same manner. Animals were sacrificed by decapitation seven days after the treatment. Total glutathione was measured in the crude mitochondrial fraction of thalamus and striatum. Total glutathione content, as a measure of reduced cell atmosphere, was mutually decreased in the thalamus and striatum of MPTP-treated animals, compared to controls: thalamus ipsi- = 24.8 +/- 3.11, contralateral = 26.81 +/- 5.31; striatum ipsi- = 19.96 +/- 4.13, contralateral = 17.3 +/- 4.09 nmol/mg prot. Mutually depleted glutathione content in the thalamus and contralateral striatum, the structures distant from ipsilateral treated striatum, could indicate on spatial propagation of oxidative stress, not only in the selective vulnerable dopaminergic nigrostriatal neurons, but in the structures included in the motor and cognitive loops of basal ganglia.


Assuntos
Estresse Oxidativo , Doença de Parkinson Secundária/metabolismo , Tálamo/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Corpo Estriado/metabolismo , Glutationa/metabolismo , Doença de Parkinson Secundária/etiologia , Ratos , Ratos Wistar
11.
J Pharm Pharmacol ; 44(1): 52-5, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1350629

RESUMO

The effect of cyclodextrin (beta-CD) on the solubility and dissolution rate of various paracetamol dispersion powders (1:1 w/w), and tablets was studied. Lower solubility was exhibited by a spray dried solid dispersion made from paracetamol-Ethocel-Macrogol 6000 (95:2:3). The improvement in solubility was influenced by complexation with beta-CD and the crystalline nature of the powder products made by different procedures. The difference in crystallinity was confirmed by X-ray powder diffraction patterns. The dissolution rate of paracetamol from tablets made from the solid dispersions was satisfactory compared with paracetamol alone. The differences between the dissolution rate from the examined paracetamol tablets resulted from the different solubility of each powder and from the structural changes of particles which influenced the consolidation of the tablet mass.


Assuntos
Acetaminofen/química , Ciclodextrinas/química , beta-Ciclodextrinas , Varredura Diferencial de Calorimetria , Cinética , Pós , Solubilidade , Comprimidos , Difração de Raios X
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