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1.
Cerebrovasc Dis ; 37(4): 296-303, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24820203

RESUMO

BACKGROUND: The Cilostazol Stroke Prevention Study 2 (CSPS 2) showed that cilostazol significantly reduced the risk of stroke by 25.7% relative to aspirin, with significantly fewer hemorrhagic events, in patients with prior ischemic stroke, excluding cardioembolic stroke. However, whether the benefit of cilostazol is sustained in patients with a high risk of bleeding has not been examined. METHODS: We conducted a subanalysis of CSPS 2 to examine whether known risk factors for hemorrhagic stroke, such as stroke subtype and systolic blood pressure (SBP), influence the efficacy of the study drugs on hemorrhagic stroke. The relative risk reduction of hemorrhagic stroke was determined from the incidences calculated by the person-year method. The cumulative incidence rates of ischemic stroke and hemorrhagic stroke were estimated and plotted using the Kaplan-Meier method. Incidences of serious hemorrhage and hemorrhage requiring hospital admission were also evaluated in the two treatment groups. Hazard ratios (HR) and 95% confidence intervals (95% CI) calculated by the Cox proportion hazard model for cilostazol versus aspirin were assessed, and a log-rank test was used for the comparison between treatments. RESULTS: The incidence of hemorrhagic stroke was significantly lower in the cilostazol group than in the aspirin group among patients with prior lacunar stroke (0.36 vs. 1.20% in person-year, HR 0.35, 95% CI 0.18-0.70, p < 0.01), but not among those with prior atherothrombotic stroke (0.31 vs. 0.59% in person-year, HR 0.53, 95% CI 0.14-2.0, p = 0.34). The incidence of hemorrhagic stroke was significantly lower in the cilostazol group than in the aspirin group throughout all SBP categories (Poisson regression model including time-dependent covariates, p < 0.01) including SBP above 140 mm Hg (cilostazol 0.45% vs. aspirin 1.44% in person-year; Poisson regression model including time-dependent covariates, p = 0.02). Cilostazol, compared with aspirin, significantly reduced the incidence of cerebral hemorrhage (HR 0.36, 95% CI 0.19-0.70, p < 0.01), overall hemorrhage requiring hospital admission (HR 0.53, 95% CI 0.29-0.97, p = 0.04), and gastrointestinal (GI) bleeding requiring hospital admission (HR 0.44, 95% CI 0.21-0.90, p = 0.03). CONCLUSIONS: Hemorrhagic stroke was less frequent in the cilostazol group than in the aspirin group among patients with lacunar stroke as well as those with increased blood pressure levels. As for extracranial hemorrhage requiring hospitalization, GI bleeding was also less frequent in the cilostazol than in the aspirin group. Cilostazol is supposed to be a therapeutic option to replace aspirin for secondary stroke prevention, especially in these subgroups with high risks for hemorrhagic events.


Assuntos
Hemorragias Intracranianas/induzido quimicamente , Inibidores da Agregação Plaquetária/efeitos adversos , Acidente Vascular Cerebral/prevenção & controle , Tetrazóis/efeitos adversos , Cilostazol , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Fatores de Risco , Tetrazóis/uso terapêutico , Resultado do Tratamento
2.
Stroke ; 39(6): 1827-33, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18388340

RESUMO

BACKGROUND AND PURPOSE: The antiplatelet agent sarpogrelate is a selective inhibitor of 5-hydroxytryptamine receptors. The purpose of this study was to compare the efficacy and safety of sarpogrelate with those of aspirin in Japanese ischemic stroke patients. METHODS: In total, 1510 patients with recent cerebral infarction (1 week to 6 months after onset) were randomly assigned to receive either sarpogrelate (100 mg TID) or aspirin (81 mg/d). Mean follow-up period was 1.59 years. The primary efficacy end point was recurrence of cerebral infarction. Clusters of serious vascular events (stroke, acute coronary syndrome, or vascular event-related death) were selected as secondary end points. The aim of the primary efficacy analysis was to demonstrate the noninferiority of sarpogrelate with respect to aspirin, with the criterion that the upper limit of the 95% CI of the hazard ratio (sarpogrelate vs aspirin) for recurrence of cerebral infarction should not exceed 1.33. RESULTS: Cerebral infarction recurred in 72 patients (6.09%/y) in the sarpogrelate group and in 58 (4.86%/y) in the aspirin group (hazard ratio=1.25; 95% CI, 0.89 to 1.77; P=0.19). A serious vascular event occurred in 90 (7.61%/y) and in 85 (7.12%/y) patients, respectively (hazard ratio=1.07; 95% CI, 0.80 to 1.44; P=0.65). The overall incidences of bleeding events were 89 (11.9%) and 131 (17.3%), respectively (P<0.01). CONCLUSIONS: Sarpogrelate was not noninferior to aspirin for prevention of recurrence of cerebral infarction. Bleeding events were significantly fewer with sarpogrelate than aspirin. The effect of aspirin in Japanese patients was similar to that in Western studies.


Assuntos
Aspirina/administração & dosagem , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/prevenção & controle , Inibidores da Agregação Plaquetária/administração & dosagem , Succinatos/administração & dosagem , Idoso , Aspirina/efeitos adversos , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/efeitos adversos , Receptores de Serotonina/efeitos dos fármacos , Receptores de Serotonina/metabolismo , Prevenção Secundária , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/efeitos adversos , Succinatos/efeitos adversos , Resultado do Tratamento
3.
Cerebrovasc Dis ; 26(1): 63-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18511873

RESUMO

BACKGROUND AND PURPOSE: Although antiplatelets are known to be effective for secondary prevention of cerebral infarction, the number needed to treat is rather large and the effects in stroke patients with complications such as hypertension or diabetes are inadequately defined. This study was conducted to examine the effect of such complications on recurrence of cerebral infarction, and to assess the effect of cilostazol, an antiplatelet agent, in these high-risk subjects. METHODS: A post hoc subgroup analysis of the already reported Cilostazol Stroke Prevention Study, which was a placebo-controlled double-blind trial, has been carried out to clarify the influence of various complications on recurrence in the placebo group and the effects of cilostazol in 1,095 patients with noncardioembolic ischemic cerebrovascular disease. Treatment continued for an average of 1.8 +/- 1.3 years (maximum 4.8 years). RESULTS: The recurrence rate of the diabetic stroke patients was significantly higher compared with the nondiabetics in the placebo group (9.4 vs. 4.7%/year, p = 0.01). Furthermore, our study showed that the relative risk reduction (RRR) for recurrence of infarction was 41.7% with cilostazol. This treatment provided a significant benefit in patients with lacunar infarction (RRR 43.4%, p = 0.04), with diabetes (RRR 64.4%, p = 0.008), or with hypertension (RRR 58.0%, p = 0.003). CONCLUSIONS: Diabetic patients are particularly at risk for recurrence of cerebral infarction. Cilostazol is useful for the prevention of the recurrence of vascular events in patients with lacunar infarction, and is probably effective in high-risk patients with diabetes and/or hypertension.


Assuntos
Isquemia Encefálica/prevenção & controle , Infarto Cerebral/prevenção & controle , Complicações do Diabetes/tratamento farmacológico , Hipertensão/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Tetrazóis/uso terapêutico , Idoso , Isquemia Encefálica/complicações , Infarto Cerebral/etiologia , Cilostazol , Método Duplo-Cego , Feminino , Humanos , Hipertensão/complicações , Japão , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Prevenção Secundária , Fatores de Tempo , Resultado do Tratamento
4.
J Neurosci ; 25(47): 10857-62, 2005 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-16306398

RESUMO

Neurofibrillary tangles (NFTs), neuropil threads, and neuritic elements of senile plaques predominantly comprise hyperphosphorylated tau protein and represent pathological characteristics of Alzheimer's disease (AD). These lesions occur before the presentation of clinical symptoms and correlate with the severity of dementia. In vivo detection of these lesions would thus prove useful for preclinical diagnosis of AD and for tracking disease progression. The present study introduces three novel compounds, 4-[2-(2-benzoimidazolyl)ethenyl]-N,N-diethylbenzenamine (BF-126), 2-[(4-methylamino)phenyl]quinoline (BF-158), and 2-(4-aminophenyl)quinoline (BF-170), as candidate probes for in vivo imaging of tau pathology in the AD brain. When solutions of these compounds are injected intravenously into normal mice, these agents exhibit excellent brain uptake and rapid clearance from normal brain tissue. These compounds display relatively lower binding affinity to beta-amyloid fibrils and higher binding affinity to tau fibrils, compared with previously reported probe BF-168. In neuropathological examination using AD brain sections, BF-126, BF-158, and BF-170 clearly visualize NFTs, neuropil threads, and paired helical filament-type neuritis. Autoradiography using 11C-labeled BF-158 further demonstrated labeling of NFTs in AD brain sections. These findings suggest the potential usefulness of quinoline and benzimidazole derivatives for in vivo imaging of tau pathology in AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Compostos de Anilina , Benzimidazóis , Encéfalo/metabolismo , Quinolinas , Proteínas tau/metabolismo , Idoso , Amiloide/metabolismo , Compostos de Anilina/administração & dosagem , Compostos de Anilina/metabolismo , Compostos de Anilina/farmacocinética , Animais , Autorradiografia , Benzimidazóis/administração & dosagem , Benzimidazóis/metabolismo , Benzimidazóis/farmacocinética , Ligação Competitiva , Encéfalo/patologia , Feminino , Humanos , Injeções Intravenosas , Masculino , Camundongos , Camundongos Endogâmicos ICR , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Tomografia por Emissão de Pósitrons , Quinolinas/administração & dosagem , Quinolinas/metabolismo , Quinolinas/farmacocinética
5.
Neuroreport ; 17(4): 413-6, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16514368

RESUMO

Disease-specific metabolic changes in Alzheimer's disease and frontotemporal dementia/Pick complex were examined by proton magnetic resonance spectroscopy at 3.0 T. Spectra were acquired from posterior and anterior cingulate cortices and the parieto-occipital and frontal white matter. This study included eight Alzheimer's disease patients, 10 frontotemporal dementia/Pick complex patients and 14 healthy volunteers. N-acetylaspartate/creatine+phosphocreatine ratio was reduced in the posterior cingulate cortex in the Alzheimer's disease and frontotemporal dementia/Pick complex patients. The Alzheimer's disease patients, however, showed a posterior dominant decrease, whereas the frontotemporal dementia/Pick complex patients showed a frontal predominant decrease. These different distributions of metabolic changes may represent the underlying pathological processes in each disease. Our standardized protocol of proton magnetic resonance spectroscopy measurement may be helpful in differentiating these dementia subtypes.


Assuntos
Doença de Alzheimer/diagnóstico , Córtex Cerebral/fisiopatologia , Demência/diagnóstico , Doença de Pick/diagnóstico , Idoso , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Mapeamento Encefálico , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Creatina/metabolismo , Demência/metabolismo , Demência/fisiopatologia , Regulação para Baixo/fisiologia , Metabolismo Energético/fisiologia , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Giro do Cíngulo/metabolismo , Giro do Cíngulo/patologia , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/metabolismo , Lobo Parietal/patologia , Lobo Parietal/fisiopatologia , Doença de Pick/metabolismo , Doença de Pick/fisiopatologia
6.
Cell Mol Immunol ; 3(1): 63-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16549052

RESUMO

In the mammalian brain, four neurotrophins have been identified: nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and neurotrophin-4/5 (NT-4/5). NGF exerts an important role in the development and functions of the central and peripheral nervous system. However, it has recently been documented that several types of immune cells, such as mast cells, lymphocytes, basophils and eosinophils, produce, store and release NGF. Accumulating preclinical and clinical data indicate that dysfunctions of NGF and the other neurotrophins may contribute to impaired immune responses and concentration of NGF frequently correlates with disease severity. Thus, the aim of this study was to elucidate the potential signaling mechanisms of cytokine- neurotrophins interactions contributing to increased NGF levels. Our data show that the transcription factor NF-kappaB plays a pivotal role in regulating B-cell-derived NGF expression.


Assuntos
Linfócitos B/metabolismo , Regulação da Expressão Gênica/imunologia , NF-kappa B/metabolismo , Fator de Crescimento Neural/biossíntese , Transdução de Sinais/imunologia , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Células Cultivadas , Camundongos , Camundongos Knockout , NF-kappa B/imunologia , Fator de Crescimento Neural/deficiência , Fator de Crescimento Neural/imunologia
7.
IEEE Trans Syst Man Cybern B Cybern ; 36(1): 74-86, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16468567

RESUMO

Measurement of volume and surface area of the frontal, parietal, temporal and occipital lobes from magnetic resonance (MR) images shows promise as a method for use in diagnosis of dementia. This article presents a novel computer-aided system for automatically segmenting the cerebral lobes from 3T human brain MR images. Until now, the anatomical definition of cerebral lobes on the cerebral cortex is somewhat vague for use in automatic delineation of boundary lines, and there is no definition of cerebral lobes in the interior of the cerebrum. Therefore, we have developed a new method for defining cerebral lobes on the cerebral cortex and in the interior of the cerebrum. The proposed method determines the boundaries between the lobes by deforming initial surfaces. The initial surfaces are automatically determined based on user-given landmarks. They are smoothed and deformed so that the deforming boundaries run along the hourglass portion of the three-dimensional shape of the cerebrum with fuzzy rule-based active contour and surface models. The cerebrum is divided into the cerebral lobes according to the boundaries determined using this method. The reproducibility of our system with a given subject was assessed by examining the variability of volume and surface area in three healthy subjects, with measurements performed by three beginners and one expert user. The experimental results show that our system segments the cerebral lobes with high reproducibility.


Assuntos
Algoritmos , Córtex Cerebral/anatomia & histologia , Lógica Fuzzy , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Humanos , Aumento da Imagem/métodos , Armazenamento e Recuperação da Informação/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
J Neurosci ; 24(10): 2535-41, 2004 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-15014129

RESUMO

Progressive deposition of senile plaques (SPs) is one of the major neuropathological features of Alzheimer's disease (AD) that precedes cognitive decline. Noninvasive detection of SPs could, therefore, be a potential diagnostic test for early detection of AD patients. For imaging SPs in the living brain, we have developed a series of styrylbenzoxazole derivatives that achieve high binding affinity for amyloid-beta (Abeta) fibrils. One of these compounds, 6-(2-Fluoroethoxy)-2-[2-(4-methylaminophenil) ethenyl]benzoxazole (BF-168), selectively binds SPs in AD brain sections and recognizes Abeta1-42-positive diffuse plaques as well as neuritic plaques in AD brain sections. Intravenous injection of BF-168 in PS1/APP and APP23 transgenic mice resulted in specific in vivo labeling to both compact and diffuse amyloid deposits in the brain. In addition, (18)F-radiolabeled BF-168 demonstrated abundant initial brain uptake (3.9% injected dose/gm at 2 min after injection) and fast clearance (t(1/2) = 24.7 min) after intravenous administration in normal mice. Furthermore, autoradiograms of brain sections from APP23 transgenic mice at 180 min after intravenous injection of [(18)F]BF-168 showed selective labeling of brain amyloid deposits with little nonspecific binding. These findings strongly suggest that styrylbenzoxazole derivatives are promising candidate probes for positron emission tomography and single-photon emission computed tomography imaging for early detection of amyloid plaque formation.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Compostos de Anilina , Benzoxazóis , Placa Amiloide/diagnóstico por imagem , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Compostos de Anilina/metabolismo , Compostos de Anilina/farmacocinética , Animais , Autorradiografia , Benzoxazóis/metabolismo , Benzoxazóis/farmacocinética , Ligação Competitiva/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Radioisótopos de Flúor , Humanos , Injeções Intravenosas , Substâncias Macromoleculares , Camundongos , Camundongos Transgênicos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/metabolismo , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos
9.
AJNR Am J Neuroradiol ; 26(6): 1498-504, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15956521

RESUMO

BACKGROUND AND PURPOSE: Selective neuronal death is a well-recognized histopathologic sequel to moderate ischemic brain damage. However, radiologic visualization of these changes has not been established, even with diffusion tensor imaging (DTI). We sought to determine whether DTI with b values > or =1900 s/mm(2) reveals occult diffusion abnormalities in patients with cerebral arterial occlusive disease. METHODS: Six patients (five men, one woman; mean age +/- standard deviation, 66 +/- 8 years) with unilateral internal carotid or middle cerebral arterial occlusive disease but not parenchymal T2 hyperintensity underwent 3T fast DTI with b < or = 1300 s/mm(2) and slow DTI with b > or = 1900 s/mm(2). We postprocessed mean diffusibility and fractional anisotropy (FA) images from the fast and slow DTI datasets. Standardized asymmetry indices (AIs) were used to identify regional asymmetries. Diagnostic accuracy among the DTI modalities was assessed by means of receiver operating characteristic analysis. RESULTS: In hemispheres ipsilateral to occluded vessel, AIs were significantly elevated on fast mean-diffusibility images of white matter at the levels of the internal capsule (95% confidence interval [CI]: 1.00, 1.09; P = .045) and corona radiata (95% CI: 1.01, 1.12; P = .034). AIs were significantly decreased on slow FA images at the internal capsule (95% CI: 0.84, 0.98; P = .018) and white matter at the internal capsule level (95% CI: 0.92, 1.00, P = .043). The slow FA map had the highest accuracy (89.8%) for detecting the hemisphere ipsilateral to arterial occlusion. CONCLUSION: Slow FA maps acquired by using DTI with high b values are useful for visualizing ischemic brain damage in apparently normal WM.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Artérias Cerebrais , Imageamento por Ressonância Magnética/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Biol Psychiatry ; 55(5): 484-9, 2004 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15023576

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) has been used as a treatment for neuropsychiatric disorders such as depression and Parkinson's disease (PD). Despite the growing interest in therapeutic application of rTMS, precise mechanisms of its action remain unknown. With respect to PD, activation of the mesostriatal dopaminergic pathway is likely to be a candidate mechanism underlying the therapeutic effects; however, modulating effects of rTMS over the primary motor cortex (M1) on the dopaminergic system have not been studied. METHODS: We used [11C]raclopride positron emission tomography to measure changes of extracellular dopamine concentration after 5Hz rTMS over the M1 in eight anesthetized monkeys. RESULTS: rTMS over the right M1 induced a reduction of [11C]raclopride binding potential (BP) in the bilateral ventral striatum, including the nucleus accumbens, and a significant increase of BP in the right putamen; no significant BP reduction was found in the dorsal striatum. These data indicate that rTMS over the motor cortex induces a release of endogenous dopamine in the ventral striatum. CONCLUSIONS: Our results suggest that therapeutic mechanisms of rTMS may be explained in part by an activation of the mesolimbic dopaminergic pathway, which plays critical roles in rewards, reinforcement, and incentive motivation.


Assuntos
Dopamina/metabolismo , Eletroconvulsoterapia , Córtex Motor/efeitos da radiação , Núcleo Accumbens/metabolismo , Putamen/metabolismo , Estimulação Magnética Transcraniana , Animais , Radioisótopos de Carbono/farmacocinética , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/metabolismo , Núcleo Caudado/efeitos da radiação , Dopamina/efeitos da radiação , Antagonistas de Dopamina/farmacocinética , Eletroconvulsoterapia/instrumentação , Eletroconvulsoterapia/métodos , Campos Eletromagnéticos , Macaca fascicularis , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/metabolismo , Vias Neurais/efeitos da radiação , Núcleo Accumbens/diagnóstico por imagem , Núcleo Accumbens/efeitos da radiação , Putamen/diagnóstico por imagem , Putamen/efeitos da radiação , Racloprida/farmacocinética , Tomografia Computadorizada de Emissão , Estimulação Magnética Transcraniana/uso terapêutico
11.
Lancet Neurol ; 2(2): 89-98, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12849265

RESUMO

Cerebrovascular disease is the second most common cause of acquired cognitive impairment and dementia and contributes to cognitive decline in the neurodegenerative dementias. The current narrow definitions of vascular dementia should be broadened to recognise the important part cerebrovascular disease plays in several cognitive disorders, including the hereditary vascular dementias, multi-infarct dementia, post-stroke dementia, subcortical ischaemic vascular disease and dementia, mild cognitive impairment, and degenerative dementias (including Alzheimer's disease, frontotemporal dementia, and dementia with Lewy bodies). Here we review the current state of scientific knowledge on the subject of vascular brain burden. Important non-cognitive features include depression, apathy, and psychosis. We propose use of the term vascular cognitive impairment, which is characterised by a specific cognitive profile involving preserved memory with impairments in attentional and executive functioning. Diagnostic criteria have been proposed for some subtypes of vascular cognitive impairment, and there is a pressing need to validate and further refine these. Clinical trials in vascular cognitive impairment are in their infancy but support the value of therapeutic interventions for symptomatic treatment.


Assuntos
Transtornos Cerebrovasculares/complicações , Transtornos Cognitivos/etiologia , Transtornos Cerebrovasculares/classificação , Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/fisiopatologia , Transtornos Cerebrovasculares/terapia , Ensaios Clínicos como Assunto , Transtornos Cognitivos/classificação , Transtornos Cognitivos/genética , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/terapia , Progressão da Doença , Humanos , Terminologia como Assunto
12.
J Mol Neurosci ; 24(2): 269-76, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15456940

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder of aging, accounting for an estimated two-thirds of all cases of senile dementia. Using bioinformatics, the yeast two-hybrid-system, reverse transcription polymerase chain reaction, and fluorescence microscopy analysis, we demonstrate here that the new putative splicing regulatory protein p18SRP is a lysine-rich zinc finger domain-containing protein that interacts with the serine-arginine (SR)-rich splicing regulatory protein SRrp86. The additional finding of its down-regulation in the brain of AD subjects points to a possible pivotal role of p18SRP in the control of cellular survival.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Regulação para Baixo , Splicing de RNA , Proteínas de Ligação a RNA/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Sequência de Aminoácidos , Animais , Encéfalo/patologia , Linhagem Celular , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Proteínas Nucleares , Proteínas de Ligação a RNA/genética , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Processamento de Serina-Arginina , Técnicas do Sistema de Duplo-Híbrido , Dedos de Zinco
13.
J Mol Neurosci ; 24(2): 247-55, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15456938

RESUMO

Extensive deposition of neuritic and diffuse amyloid plaques in the brain is a critical event for the pathogenesis of Alzheimer's disease (AD) and considered to start before the appearance of clinical symptoms. In vivo detection of these brain beta-amyloid (Abeta) deposits using positron emission tomography (PET), therefore, would be a useful marker for presymptomatic detection of AD. To develop a new agent for PET probe of imaging neuritic and diffuse amyloid deposits, novel fluorescent compounds, including styryl-fluorobenzoxazole derivatives, were examined. These compounds showed a high binding affinity for both synthetic Abeta1-40 and Abeta1-42 aggregates. Some of these compounds also displayed distinct staining of neuritic and diffuse amyloid plaques in AD brain sections. A biodistribution study of styryl-fluorobenzoxazole derivatives in normal mice exhibited excellent brain uptakes (4.5-5.5% injected dose/g at 2 min postinjection). Furthermore, iv administration of BF-145, a styryl-fluorobenzoxazole derivative, demonstrated specific in vivo labeling of compact and diffuse amyloid deposits in an APP23 transgenic mouse brain, in contrast to no accumulation in a wild-type mouse brain. These findings suggest that BF-145 is a potential candidate as a probe for imaging early brain pathology in AD patients.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Encéfalo/patologia , Diagnóstico por Imagem , Corantes Fluorescentes/metabolismo , Placa Amiloide , Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Benzoxazóis/química , Benzoxazóis/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Feminino , Corantes Fluorescentes/química , Compostos de Flúor/química , Compostos de Flúor/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Placa Amiloide/química , Placa Amiloide/metabolismo , Placa Amiloide/patologia
14.
Brain Res Mol Brain Res ; 104(2): 127-31, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12225865

RESUMO

Post-transcriptional regulatory mechanisms have been shown to play a major role in gene expression in eukaryotic cells. Sequences within the 3'-untranslated region (3'UTR) of mRNAs have been described as being important for enhancing or inhibiting message translation. Using fluorescence microscopy, Western blotting and the reverse transcription-polymerase chain reaction (RT-PCR) method, we demonstrate that the 3'UTR of the new rat transcript of synaptic vesicle protein 2B (SV2Bb) mRNA is involved in post-transcriptional regulation of SV2Bb translation. When fused to a reporter gene, this 3'UTR markedly inhibited protein synthesis in transiently transfected cells and this decreased translational efficiency did not occur through changes in mRNA stability. In conclusion, our study gives new insights into unraveling the molecular mechanisms involved in the post-transcriptional regulation of the SV2B gene.


Assuntos
Regiões 3' não Traduzidas/genética , Sistema Nervoso Central/metabolismo , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso/genética , Terminações Pré-Sinápticas/metabolismo , Biossíntese de Proteínas/genética , RNA Mensageiro/genética , Vesículas Sinápticas/metabolismo , Animais , Células CHO , Cricetinae , Regulação da Expressão Gênica/genética , Genes Reporter/genética , Proteínas de Fluorescência Verde , Proteínas Luminescentes , Proteínas do Tecido Nervoso/biossíntese , Estrutura Terciária de Proteína/genética , RNA Mensageiro/metabolismo , Ratos , Transmissão Sináptica/genética , Transcrição Gênica/genética
15.
Exp Mol Med ; 36(2): 130-4, 2004 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-15150441

RESUMO

Apoptosis, the cell's intrinsic death program, plays a crucial role in the regulation of tissue homeostasis, and abnormal inhibition of apoptosis is an indicator of cancer and autoimmune diseases, whereas excessive cell death is implicated in neurodegenerative disorders such as Alzheimer's disease (AD). Using cDNA subtraction analysis, we compared p60TRP (p60 transcription regulator protein) expressing cells with control cells during the process of apoptosis and we identified the new zinc-finger protein p48ZnF that is predominantly located in the cytoplasm of the cell. Additionally, we demonstrate here that p48ZnF is up-regulated in rat neuronal PC12 cells upon stimulation with the neurotrophic factor NGF (50 ng/ml). These findings point to a possible pivotal role of p48ZnF in the control of neuronal survival.


Assuntos
Citoplasma/metabolismo , Proteínas de Ligação a DNA/biossíntese , Fator de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/biossíntese , RNA Mensageiro/biossíntese , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Dedos de Zinco/genética , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Apoptose , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Sequência de Bases , Biomarcadores , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Clonagem Molecular , Cricetinae , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Dados de Sequência Molecular , Neoplasias/metabolismo , Células PC12 , Ratos , Transfecção
16.
Restor Neurol Neurosci ; 22(2): 131-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15272147

RESUMO

Alzheimer's disease (AD) is one of the most common and challenging neurodegenerative diseases in humans and is characterized by: progressive impairment in cognitive function, degeneration of cholinergic neurons of the basal forebrain (CBF), neurofibrillary tangles and amyloid beta-peptide (Abeta) depositions. The amyloid precursor protein (APP) is a transmembrane protein of which abnormal processing produces Abeta that is associated with the pathogenesis of AD. Neurotrophic factors have attracted much attention for their potential as a remedy for neurological disorders. In this regard, nerve growth factor (NGF) has generated a great interest as a potential target for the treatment of AD. This interest is based on the observation that CBF neurons, which provide the major source of cholinergic innervation to the cerebral cortex and hippocampus, undergo selective and severe degeneration in advanced AD and that the survival of CBF neurons depends upon NGF and its receptors, namely, trkA and p75NTR. This review focuses on recent findings about APP, NGF and their potential signaling-connections to the protein encoded by the 'Sunday-driver' (SYD) gene.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Fator de Crescimento Neural/metabolismo , Transdução de Sinais/fisiologia , Doença de Alzheimer/patologia , Animais , Humanos
17.
Neuroreport ; 13(1): 183-6, 2002 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-11924885

RESUMO

To investigate metabolic changes in Alzheimer's disease (AD), we performed proton MR spectroscopy at 3T Spectra were acquired from the gray matter of the posterior cingulate gyrus and the precuneus, and from the parietooccipital white matter in nine AD patients and 12 controls. In patients, the N-acetyl group (NA)/creatine + phosphocreatine (Cr) ratios were decreased in both regions, and a decrease in the glutamate + glutamine (Glx)/Cr ratio and a correlation between the NA/Cr and Glx/Cr ratios were detected in the gray matter, but not in the white matter. These results suggest that NA and Glx metabolism are simultaneously affected in AD, however, metabolic changes in Glx are more profound in the gray matter than in the white matter.


Assuntos
Doença de Alzheimer/metabolismo , Ácido Aspártico/análogos & derivados , Encéfalo/metabolismo , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Espectroscopia de Ressonância Magnética , Idoso , Ácido Aspártico/metabolismo , Creatina/metabolismo , Feminino , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética/métodos , Masculino , Fosfocreatina/metabolismo , Valores de Referência , Distribuição Tecidual
18.
Neurosci Res ; 48(1): 65-74, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14687882

RESUMO

Detection of aggregated amyloid-beta (Abeta) with a non-invasive imaging modality such as positron emission tomography (PET) was suggested to be ideal for the diagnosis of Alzheimer's disease (AD) prior to the onset of clinical symptoms. We have been searching for imaging probe candidates with a high affinity for aggregated Abeta in vitro and in vivo and high lipophilicity, a characteristic that allows for the permeation of the blood-brain barrier (BBB). As analyzed by Thioflavin T (ThT) assay and octanol/water partition coefficient test (PC), 3-diethylamino-6-(2-fluoroethyl)ethylaminoacridine (BF-108) were found to have high affinity for Abeta aggregates in vitro and high lipophilicity. Intravenously administrated BF-108 labeled Abeta aggregates injected into the amygdala as observed under a fluorescence microscope, showing this compound's permeability of BBB and an ability to label Abeta in vivo. BF-108 also labeled neuritic senile plaques (SPs), neurofibrillary tangles, and amyloid-laden vessels in temporal and hippocampal sections from AD patients. Following intravenous administration of BF-108 to an APP23 transgenic (TG) mouse, in vivo labeling of endogenous plaques was seen in brain sections by fluorescence microscopy. These properties suggest the potential utility of BF-108 for in vivo imaging of AD pathology.


Assuntos
Acridinas/metabolismo , Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Encéfalo/metabolismo , Corantes Fluorescentes/metabolismo , Acridinas/administração & dosagem , Acridinas/química , Marcadores de Afinidade/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Benzotiazóis , Encéfalo/patologia , Feminino , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/química , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Transgênicos , Microscopia de Fluorescência/métodos , Emaranhados Neurofibrilares/metabolismo , Placa Amiloide/metabolismo , Ratos , Ratos Wistar , Tiazóis/metabolismo
19.
Pharmacol Biochem Behav ; 71(1-2): 119-38, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11812515

RESUMO

In order to fully evaluate the effects of colchicine treatment on learning ability in rats, colchicine was administered, and both Morris water maze (MWM) and step-through type passive avoidance (PA) learning tests were conducted. In both learning tests, infusion of colchicine into the rat dentate gyrus, at two distinct bilateral rostrocaudal locations, potently impaired memory function in a dose-dependent manner (0.01-2.0 microg/site), whereas systemic injection of colchicine (50-300 microg/kg) did not. In the MWM test, memory impairment was observed even at doses where there was no evidence of any histological changes in the dentate granule cells. This suggests that functional deterioration, that is, learning impairment was induced by the dysfunction of microtubules and/or axons, was caused by colchicine. Moreover, ameliorated learning behavior was observed with chronic treatment of beta-estradiol 3-benzoate, which has been suggested to have an important role as an adjuvant treatment for younger Alzheimer's disease (AD), immediately after colchicine infusion (0.3 microg). These results indicate that the animal model accompanying the colchicine-induced functional defect showing early tau pathology, but not neuronal cell degeneration, may well mimic comparatively early stage of AD.


Assuntos
Colchicina/efeitos adversos , Estradiol/análogos & derivados , Transtornos da Memória/induzido quimicamente , Microtúbulos/efeitos dos fármacos , Doença de Alzheimer/patologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Aprendizagem da Esquiva/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/patologia , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Estradiol/uso terapêutico , Supressores da Gota/efeitos adversos , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/patologia , Microtúbulos/patologia , Ratos , Ratos Sprague-Dawley
20.
Magn Reson Med Sci ; 3(1): 1-9, 2004 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16093614

RESUMO

MRI (magnetic resonance imaging) with 129Xe has gained much attention as a diagnostic methodology because of its affinity for lipids and possible polarization. The quantitative estimation of net detectability and stability of hyperpolarized 129Xe in the dissolved phase in vivo is valuable to the development of clinical applications. The goal of this study was to develop a stable hyperpolarized 129Xe experimental 3T system to statistically analyze the dissolved-phase 129Xe signal in the rat lungs. The polarization of 129Xe with buffer gases at the optical pumping cell was measured under adiabatic fast passage against the temperature of an oven and laser absorption at the cell. The gases were insufflated into the lungs of Sprague-Dawley rats (n = 15, 400-550 g) through an endotracheal tube under spontaneous respiration. Frequency-selective spectroscopy was performed for the gas phase and dissolved phase. We analyzed the 129Xe signal in the dissolved phase to measure the chemical shift, T2*, delay and its ratio in a rat lungs on 3T. The polarizer was able to produce polarized gas (1.1+/-0.47%, 120 cm3) hundreds of times with the laser absorption ratio (25%) kept constant at the cell. The optimal buffer gas ratio of 25-50% rendered the maximum signal in the dissolved phase. Two dominant peaks of 211.8+/-0.9 and 201.1+/-0.6 ppm were observed with a delay of 0.4+/-0.9 and 0.9+/-1.0 s from the gas phase spectra. The ratios of their average signal to that of the gas phase were 5.6+/-5.2% and 4.4+/-4.7%, respectively. The T2* of the air space in the lungs was 2.5+/-0.5 ms, which was 3.8 times shorter than that in a syringe. We developed a hyperpolarized 129Xe experimental system using a 3T MRI scanner that yields sufficient volume and polarization and quantitatively analyzed the dissolved-phase 129Xe signal in the rat lungs.


Assuntos
Pulmão/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Isótopos de Xenônio , Administração por Inalação , Animais , Aumento da Imagem , Gases Nobres/administração & dosagem , Gases Nobres/farmacocinética , Ratos , Ratos Sprague-Dawley , Isótopos de Xenônio/administração & dosagem , Isótopos de Xenônio/farmacocinética
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