Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
World J Surg ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109792

RESUMO

OBJECTIVE: It has recently been suggested that the formation of pulmonary vein stump thrombus (PVST) after anatomical lung resection is an underlying cause of arterial thromboembolism including cerebrovascular infarction. This study aimed to investigate the incidence and risk factors of PVST and to evaluate the efficacy and safety of anticoagulant therapy for PVST. METHODS: Patients who underwent anatomical lung resection for malignant lung tumors were eligible for inclusion in this study. Chest contrast-enhanced (CE) computed tomography (CT) was performed after surgery to detect PVST. If PVST was observed, patients received anticoagulant therapy. The size of the PVST was followed-up by repeated chest CE-CT. RESULTS: In total, 176 patients were enrolled in this study. Chest CE-CT was performed on postoperative day 1-13 (median, postoperative day 6). PVST was detected in 22 (12.5%) patients. The median size of PVST was 9.5 (4.1-33.4) mm. Thrombus was most commonly observed in patients who underwent left upper lobectomy (9/36, 25.0%). Hypertension, dyslipidemia, arteriosclerosis, and arrhythmia were not associated with PVST formation. Anticoagulant therapy was administered to all 22 patients with PVST until the PVST disappeared. The median duration between the detection and disappearance of PVST was 77 days (range: 6-146 days). During the period between the detection and disappearance of PVST, cerebrovascular infarction or arterial thromboembolic events were not observed. CONCLUSIONS: Postoperative PVST is commonly observed, especially in patients who undergo left upper lobectomy. Anticoagulant therapy for PVST was safely introduced and was efficient to improve PVST without subsequent arterial thromboembolic events.

2.
J Stroke Cerebrovasc Dis ; 26(7): 1521-1527, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28363514

RESUMO

BACKGROUND: Ischemic stroke is one form of cancer-associated thrombosis that can greatly worsen a patient's performance status. The present investigation aimed to elucidate the characteristic distribution pattern(s) of cryptogenic stroke lesions using a voxel-based lesion-mapping technique and examine the differences in clinical manifestations between cryptogenic and conventional strokes in patients with advanced cancer. METHODS: Data from 43 patients with advanced cancer who developed acute ischemic stroke were retrospectively collected. Stroke etiology was grouped into either cryptogenic or conventional stroke etiology according to the ASCO stroke score. Clinical data were reviewed, and voxel-based lesion mapping using diffusion-weighted imaging (DWI) was performed to visualize the cross-patient spatial distribution of the lesions. RESULTS: Of the 43 patients, 25 were classified as having cryptogenic stroke etiology and 18 were classified as having conventional stroke etiology. Median survival time of patients from stroke onset was 96 days for cryptogenic stroke etiology and 570 days for conventional stroke etiology (P = .01). D-dimer of patients was significantly higher in cryptogenic stoke etiology than in conventional stroke etiology (P = .006). Voxel-based lesion mapping showed that DWI hyperintense lesions accumulated at cortical and internal watershed areas of the cerebrum and at the vascular border zone of the superior cerebellar and posterior inferior cerebellar arteries at the cerebellum. CONCLUSIONS: Voxel-based lesion mapping for cryptogenic stroke in patients with advanced cancer showed that lesions accumulated at vascular border zones within the brain both at the cerebrum and at the cerebellum, but not at perforating arterial territories.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Interpretação de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo
3.
Yakugaku Zasshi ; 144(4): 381-385, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38556311

RESUMO

NMR is well known as one of the most important methods for elucidating the structure of organic compounds. Furthermore, it has recently been recognized as a powerful tool for quantitative analysis. The quantitative NMR (qNMR) has become an official analytical method described in detail in the Japanese Pharmacopoeia. And today, it is widely applied in drug development. The qNMR method offers many new advantages over traditional and conventional quantitative analysis methods. For example, this method requires only a few milligrams of the analyte and allows absolute quantitation of the analyte without using a qualified reference standard as a control sample. Then, it can be easily applied to most chemicals without expending significant time and resources on method development. In addition, residual solvent can be determined using qNMR methods. The peak area of an NMR spectrum is directly proportional to the number of protons contributing to the resonance. Based on this principle, the residual solvent can be determined by counting the signal corresponding to the residual solvent in the sample solution. We have applied qNMR as an alternative to GC. Thus, qNMR is an innovative and promising analytical technique that is expected to make significant progress in the future. Recently, the analytical research and quality control departments have been working together to expand this technology to a wide range of areas in the pharmaceutical industry.


Assuntos
Indústria Farmacêutica , Espectroscopia de Ressonância Magnética/métodos , Controle de Qualidade , Padrões de Referência , Solventes
4.
J Clin Microbiol ; 46(10): 3397-403, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18685011

RESUMO

Norovirus (NoV) infections are the major cause of food- and waterborne nonbacterial gastroenteritis in Japan. Some individuals showed long-term excretion of the virus into feces in 29 outbreaks of acute nonbacterial gastroenteritis that occurred in Toyama Prefecture, Japan, in fiscal year 2006. In one of these cases, single base substitutions from A to G in the capsid region of the NoV genome were commonly detected in two individuals during virus shedding by direct sequencing of PCR products. The A-to-G substitution was accompanied by an N-to-S amino acid change. The population of clones that possessed A at the corresponding site was gradually replaced by those with G during the infectious course. Although other substitutions were observed in the complete open reading frame 2 sequence, they were not common in these two individuals. NoVs are capable of evolving in the gastroenteric tract.


Assuntos
Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/genética , Gastroenterite/virologia , Norovirus/genética , Mutação Puntual , Eliminação de Partículas Virais , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Sequência de Bases , Infecções por Caliciviridae/epidemiologia , Surtos de Doenças , Doenças Endêmicas , Fezes/virologia , Gastroenterite/epidemiologia , Humanos , Japão/epidemiologia , Dados de Sequência Molecular , Norovirus/classificação , Norovirus/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência
5.
Eur Neurol ; 60(3): 137-41, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18628632

RESUMO

AIMS: To find neurological or neuroimaging signs to predict neurological deterioration in acute lacunar infarctions. METHODS: Sixty-one consecutive patients with a supratentorial lacunar infarct, who were admitted within 48 h, were studied retrospectively. Progressive-type stroke (PS) was defined as progressive motor deficits that arose within 7 days after onset, by using the motor ratings of the National Institutes of Health Stroke Scale. RESULTS: Sixteen patients (26%) were classified into the PS group. In the PS group, fluctuating or progressing onset (81 vs. 42%, p = 0.009), leg-predominant motor deficits on admission (63 vs. 16%, p = 0.001) and corona radiata lesion on diffusion-weighted MRI (100 vs. 69%, p = 0.013) were all more frequent than in the non-PS group. CONCLUSION: Bedside neurological assessment and MRI findings may allow us to predict PS and start early intensive treatment for preventing further neurological deterioration.


Assuntos
Infarto Encefálico/diagnóstico , Encéfalo/patologia , Imageamento por Ressonância Magnética , Idoso , Criança , Progressão da Doença , Humanos , Lactente , Exame Neurológico , Prognóstico , Estudos Retrospectivos
6.
Eur Neurol ; 59(1-2): 38-43, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17917456

RESUMO

BACKGROUND/AIMS: The aim of this study is to clarify the relationship between lesion detectability by diffusion-weighted magnetic resonance imaging (DWI) and the etiology of transient ischemic attacks (TIAs). METHODS: A retrospective study was performed on 72 patients with carotid TIAs who underwent DWI studies within 2 weeks after the last episode. RESULTS: Lesions were detected in 24 of 72 patients (33%). The detectability of lesions was 12% (3/25) in the large-artery atherosclerosis (LA) group, 57% (8/14) in the cardioembolism (CE) group, 8% (1/13) in the small-artery occlusion (SA) group, and 60% (12/20) in the other etiology or undetermined etiology (UD) group. Detectabilities in the CE group and the UD group were higher than those in the LA and SA groups. Of 24 patients with DWI-positive lesions, 17 (71%) had embolic sources in the heart; 9 were classified in the UD group because they had embolic sources both in the heart and large artery. CONCLUSION: Ischemic DWI lesions in TIAs are most likely caused by a cardioembolic mechanism. In TIA patients showing lesions on DWI, heart disease should be surveyed as the possible embolic source.


Assuntos
Infarto Cerebral/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Embolia/complicações , Ataque Isquêmico Transitório/diagnóstico , Ataque Isquêmico Transitório/etiologia , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo
7.
AJNR Am J Neuroradiol ; 26(4): 809-14, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15814925

RESUMO

BACKGROUND AND PURPOSE: Multiple acute brain infarctions in both cerebral hemispheres usually suggest an embolic mechanism, particularly one of aortic or cardiac origin. The purpose of this study was to clarify the etiologic mechanisms and topographic features of bihemispheric infarctions depicted on diffusion-weighted imaging (DWI). METHODS: Among 411 consecutive patients with ischemic stroke who underwent MR imaging in the acute phase, DWI showed bilateral infarctions in 19 (4.6%). In these patients, we analyzed the presence of carotid, aortic or cardiac embolic sources by using ultrasonography, cerebral angiography, and/or transesophageal echocardiography and evaluated the size and topographic distribution of the lesions. We assessed intracranial cross-flow through the anterior communicating artery, mainly on the basis of the anatomic information obtained from angiography or MR angiography. RESULTS: Bilateral lesions were derived from cardiac and/or aortic embolic sources in 16 (84%) of 19 patients and appeared to originate from unilateral carotid diseases in three (16%). In nine (82%) of 11 patients with cardiac embolic sources, at least one large territorial or subcortical lesion was found in either hemisphere, whereas in all eight patients without a cardiac embolic source, the lesions were small and disseminated bilaterally. CONCLUSION: Unilateral carotid lesions can cause bihemispheric infarctions through cross-flow in the anterior communicating artery. On DWI, small bihemispheric, disseminated lesions strongly suggest an artery-to-artery embolism. In such cases, aortic and carotid lesions should be assessed as potential embolic sources.


Assuntos
Infarto Encefálico/diagnóstico , Infarto Encefálico/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Idoso , Idoso de 80 Anos ou mais , Circulação Cerebrovascular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Intern Med ; 44(5): 434-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15942089

RESUMO

OBJECTIVE: Purpose was to assess the stroke mechanism in patients with patent foramen ovale (PFO). METHODS: We reviewed the medical records of 111 stroke patients with PFO and sinus rhythm (PFO-S group), 25 with PFO and atrial fibrillation (AF) (PFO-AF group) and 67 with AF but not PFO (AF group), who had received contrast transesophageal echocardiography. The clinical and neuroradiological findings were then compared among the three groups. Deep vein thrombosis was investigated in 93 patients with PFO. We determined the number of patients with definite paradoxical embolism who met three criteria: deep vein thrombosis, neuroradiological features indicating embolic stroke, and the absence of other sources of emboli. We also evaluated those with probable paradoxical embolism who met two of the three criteria. RESULTS: The PFO-S group more frequently exhibited hypercholesterolemia (p<0.0001) and lesions limited to the posterior circulation (p<0.0004), and less frequently exhibited large or cortical lesions in the anterior circulation (p=0.0008, p<0.0001, respectively), than the PFO-AF and AF groups. In the PFO-S and PFO-AF groups, other sources of emboli such as a cardiac source of emboli, cerebral artery stenosis > or =50%, or complicated atheroma in the aortic arch were identified in 72 cases (52.9%). In the 93 patients with examination for deep vein thrombosis, the definite and probable criteria of paradoxical embolism were fulfilled only in three (3.2%) and 33 cases (35.5%), respectively. CONCLUSION: In stroke patients with PFO, not only paradoxical brain embolism through the PFO but also other causes of stroke may contribute to the development of stroke.


Assuntos
Embolia Paradoxal/complicações , Comunicação Interatrial/complicações , Infarto da Artéria Cerebral Anterior/etiologia , Infarto da Artéria Cerebral Posterior/etiologia , Idade de Início , Idoso , Artéria Cerebral Anterior , Artérias Carótidas/diagnóstico por imagem , Angiografia Cerebral , Ecocardiografia Transesofagiana , Eletrocardiografia , Embolia Paradoxal/diagnóstico , Embolia Paradoxal/epidemiologia , Feminino , Seguimentos , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interatrial/fisiopatologia , Humanos , Incidência , Infarto da Artéria Cerebral Anterior/diagnóstico , Infarto da Artéria Cerebral Anterior/epidemiologia , Infarto da Artéria Cerebral Posterior/diagnóstico , Infarto da Artéria Cerebral Posterior/epidemiologia , Japão/epidemiologia , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Posterior , Estudos Retrospectivos , Fatores de Risco
9.
Stroke ; 35(6): 1426-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15118179

RESUMO

BACKGROUND AND PURPOSE: Aortic arch atherosclerotic lesions are often associated with embolic brain infarction. We investigated the relationship between stroke recurrence and the characteristics of aortic arch atherosclerotic lesions. METHODS: Among 487 stroke patients who underwent transesophageal echocardiography, 283 patients with brain embolism diagnosed without significant occlusive lesions (> or =50%) in their cerebral arteries were included in this study. We measured the intima-media thickness (IMT) and evaluated the extension and mobility of the aortic arch atherosclerotic lesions. During a mean follow-up period of 3.4 years, we investigated the relationship between stroke recurrence and the various characteristics of the aortic arch atherosclerotic lesions. RESULTS: An IMT > or =4.0 mm was found in 67 patients (25.3%). In 51 of these patients, the aortic lesions extended to the origin of the branches of the arch. Recurrences of cerebral ischemic events were found in 32 patients (recurrence group) and not in the other 251 (nonrecurrence group). Aortic atheroma > or =4.0 mm (41% versus 22%), aortic atheroma extending to the branches (63% versus 39%), and both (38% versus 16%) were more frequently seen in the recurrence group than in the nonrecurrence group (P<0.05, P<0.1, P<0.01, respectively). After adjustment for age and the presence of hypertension, an aortic atheroma that was > or =4.0 mm as well as extending to the branches was found to be an independent predictor of ischemic stroke recurrence (hazard ratio=2.42, P<0.05). CONCLUSIONS: Stroke recurrence is associated with the severity of the atheroma (IMT > or =4.0 mm) and plaque extension to the branches.


Assuntos
Aorta Torácica/patologia , Arteriosclerose/patologia , Isquemia Encefálica/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Arteriosclerose/complicações , Infarto Encefálico/etiologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Incidência , Embolia Intracraniana/complicações , Masculino , Pessoa de Meia-Idade , Recidiva , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia
10.
Neurosci Res ; 44(4): 483-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12445636

RESUMO

In auditory evoked magnetic fields (AEFs), the latency of temporal N100m response elicited by the ipsilateral ear stimulation (Ipsi-Stim) is generally longer than that of N100m response elicited by the contralateral ear stimulation (Cont-Stim). The reason for this difference remains unclear. We measured AEFs in patients with fronto-temporal or frontal lobe infarction to clarify this question. In the patients with fronto-temporal lobe infarction, the N100m peak latencies in the healthy hemisphere by Ipsi-Stim measurements were significantly longer than the corresponding normal values. Such a latency prolongation was not observed in the patients with frontal lobe infarction. The results suggest that auditory impulses originated from the ear may first arrive at the contralateral temporal cortex and then return to the ipsilateral temporal cortex mediating through the corpus callosum. The disturbance of interhemispheric conduction by ischemic temporal lesions likely delays the N100m latency at the contralateral temporal cortex. The mediation of interhemispheric route may, thus, make the ipsilateral N100m latency generally longer than the contralateral N100m latency.


Assuntos
Vias Auditivas/fisiopatologia , Infarto Cerebral/fisiopatologia , Corpo Caloso/fisiopatologia , Lobo Frontal/fisiopatologia , Lateralidade Funcional/fisiologia , Lobo Temporal/fisiopatologia , Estimulação Acústica , Idoso , Vias Auditivas/patologia , Mapeamento Encefálico , Infarto Cerebral/patologia , Potenciais Evocados Auditivos/fisiologia , Feminino , Lobo Frontal/patologia , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Tempo de Reação/fisiologia , Lobo Temporal/patologia
11.
Neurosci Res ; 44(3): 273-83, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12413656

RESUMO

The purpose of this study was to determine whether the auditory cortex is sensitive to cortical insults and to determine the specificity of the insults in three clinical situations with different cortical involvement. Auditory-evoked magnetic fields of ten normal subjects, 8 patients with right hemispheric infarction, 11 with chronic dizziness, and 2 with moyamoya disease were measured. To analyze the abnormality of auditory neural networks, the magnitude ratio and the angle difference (Deltatheta) between response vectors, which were determined from maximum current arrows corresponding to the N100m peak for contralateral and ipsilateral stimuli were used. A normal range of the parameters was defined so that abnormal values could be determined. Of the three parameters, Deltatheta was the most sensitive: 4 patients with right hemispheric infarction, 4 with chronic dizziness, and 1 with moyamoya disease had abnormal Deltatheta. The electrical activity in the patients with such abnormal Deltathetas had a circular current pattern. These findings suggest that right infarction lesions sometime affect the left auditory neural network, dizziness is caused by abnormal neural networks between the vestibular cortical area and the auditory cortex or by an imbalance between left and right auditory-cortex activities, and moyamoya-disease patients have almost normal auditory-electrical activity.


Assuntos
Percepção Auditiva/fisiologia , Infarto Cerebral/fisiopatologia , Tontura/fisiopatologia , Doença de Moyamoya/fisiopatologia , Rede Nervosa/fisiopatologia , Estimulação Acústica , Adulto , Idoso , Algoritmos , Doença Crônica , Feminino , Lateralidade Funcional/fisiologia , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade
12.
Neurosci Res ; 46(3): 281-8, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12804789

RESUMO

The aim of this study was to investigate neural activity during period of vertiginous sensation, induced by caloric stimulation. After caloric vestibular stimulation (CVS) by cold water of five volunteers (n=5, age: 30+/-10), auditory evoked magnetic fields (AEFs) during the subsequent period of vertiginous sensations were measured by magnetoencephalography (MEG). Current-arrow maps (CAMs) were produced to estimate the spatial current distribution of the AEF responses, and a rotation value (dI(rot)) was calculated from the CAM. The worth of the dI(rot) values as indicators of vertigo was evaluated by comparing them with earlier reported values for elderly control (n=11, age: 67+/-5) and chronic dizziness (CD) (n=27, age: 68+/-8) groups (obtained from AEF responses with no the CVS). Although all volunteers felt vertigo during the AEF measurements, the AEF waveforms and CAM pattern only showed slight changes. While the dI(rot) values (1.43+/-0.73) just after CVS were not significantly different from those (1.59+/-0.46) for the elderly controls, they were significantly different from those (3.54+/-1.34) for the CD patients. These findings suggest that (i) the new parameter (dI(rot)) is more sensitively indicates dizziness (non-rotatory sensation) than vertigo (ii) the auditory cortical region may play an important role in body-balance perception of floating sensations.


Assuntos
Testes Calóricos , Temperatura Baixa/efeitos adversos , Magnetoencefalografia/métodos , Vertigem/fisiopatologia , Estimulação Acústica , Adulto , Idoso , Envelhecimento , Algoritmos , Mapeamento Encefálico , Doença Crônica , Tontura/fisiopatologia , Eletronistagmografia/métodos , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rotação , Lobo Temporal/fisiopatologia , Fatores de Tempo
13.
Neurosci Res ; 49(2): 253-60, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15140567

RESUMO

To develop a new measurement tool for quantitatively detecting the finger movement of a patient with Parkinson's disease (PD), we designed a magnetic sensing system consisting of a magnetic induction coil, a sensing coil, and a circuit unit. The sensing coil detects the inducted magnetic field that varies with the distance between the two coils, and the detected signals are demodulated in the circuit unit in order to obtain the variation voltage from the oscillation frequency. To obtain a coefficient for converting voltage to distance, we measured the output voltages for seven fixed finger positions of 12 normal volunteers. The voltage differences corresponding to the finger movement in 20 PD patients, six age-matched controls, and 12 normal volunteers were then recorded for 30s. To investigate the velocity and acceleration of the finger movement, we calculated their waveforms from the measured displacement waveform. We also detected the main frequency of the tapping rhythm by using a fast Fourier transform (FFT). The averaged amplitude of each waveform decreased with the disorder in the Hoehn-Yahr (HY) stage, while the averaged tapping frequency of PD patients did not have any correlation with this stage. It can be concluded that this magnetic sensing system can assess finger movement quantitatively.


Assuntos
Dedos/fisiopatologia , Movimento/fisiologia , Doença de Parkinson/fisiopatologia , Desempenho Psicomotor/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Eletricidade , Feminino , Análise de Fourier , Lateralidade Funcional/fisiologia , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Tempo de Reação , Fatores Sexuais , Pesos e Medidas
14.
Brain Res ; 957(2): 373-81, 2002 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-12445982

RESUMO

A long-lasting dizzy sensation is a common complaint in elderly subjects. The pathogenesis and effective treatment of such chronic dizziness (CD), however, have not yet been fully elucidated because of lack of methods for evaluating this sensation. On the basis of assumption that CD may be attributable partly to cortical functional abnormality, we attempted to estimate the function of auditory cortex by measurements of auditory-evoked magnetic fields (AEFs). Magnetic field signals in the parieto-temporal cortex were evoked by 1000-Hz tone-burst with 90-dB normal hearing level sounds, and the highest-amplitude magnetic waveforms at approximately 100-ms (N100m) were analyzed as electrical current arrows in normal subjects (n=11), patients with CD (n=27) and patients with cerebral infarction but no dizzy sensation (n=9). In the normal subjects, the current arrows pointed to a nearly straight line with small directional distortion as indicated by a rotation-degree parameter, dI(rot) of 1.59+/-0.46. In 17 of 27 CD patients, the directions of current arrows were markedly distorted showing abnormally high dI(rot) values greater than 2.50 (the mean plus two standard deviations of normal values) and disclosed a clockwise or counter-clockwise rotation in either side or both sides of parieto-temporal cortex. In all the patients with cerebral infarction, the current arrows exhibited the similar pattern as the normal subjects. None of them exhibited abnormally high dI(rot) values. We hypothesized that the rotational abnormality may be caused by abnormal neuronal excitation, since non-evoked magnetic fields in temporal lobe epilepsy demonstrated the similar current rotational abnormality as reported previously. Seven CD patients were treated with anticonvulsants, and four showed remarkable amelioration of dizzy sensation. In all the four patients with symptomatic amelioration, the disappearance of rotational abnormality in AEFs or the tendency towards disappearance was observed following symptomatic amelioration. The results of the present study suggest that the auditory center may contribute to the maintenance of equilibrium, and its dysfunction may lead to the development of CD. AEFs measurements may make it possible to evaluate the functional abnormality of auditory center and may be useful for studying the pathophysiology and treatment of CD.


Assuntos
Córtex Auditivo/fisiopatologia , Doenças Auditivas Centrais/fisiopatologia , Tontura/fisiopatologia , Potenciais Evocados Auditivos/fisiologia , Estimulação Acústica , Idoso , Anticonvulsivantes/uso terapêutico , Córtex Auditivo/efeitos dos fármacos , Doenças Auditivas Centrais/tratamento farmacológico , Mapeamento Encefálico , Infarto Cerebral/patologia , Infarto Cerebral/fisiopatologia , Doença Crônica , Tontura/tratamento farmacológico , Feminino , Lateralidade Funcional/fisiologia , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Lobo Parietal/fisiopatologia , Equilíbrio Postural/fisiologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Rotação , Ácido Valproico/uso terapêutico
15.
Rinsho Shinkeigaku ; 44(8): 522-6, 2004 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-15471087

RESUMO

We report a 46-year-old woman with Buerger's disease who presented vascular dementia. In her early thirties, she began to feel cold sensation and pain in the lower extremities and later developed Raynaud's phenomenon in the upper extremities. The diagnosis of Buerger's disease was established on the basis of angiographic findings which showed the obstruction of peripheral vessels in both anterior tibial arteries. She was admitted to our hospital because of a transient attack of left brachial monoparesis and two episodes of epileptic seizure with progressive cognitive impairment for preceding five years. Neurological examination revealed acalculia, constructional apraxia, recent memory disturbance, and hyperreflexia of the left limbs without motor disturbance. Brain MRI revealed multiple infarctions mainly located in the border zone territories of the major cerebral arteries. Conventional angiography failed to detect abnormalities of cerebral vessels. She had no cardiovascular abnormality or coagulopathy. Cerebrovascular complications, so-called cerebral thoromboangiitis obliterans (CTAO), occur approximately in 2% of patients with Buerger's disease. CTAO has two types. Type 1 is associated with large artery changes and type 2 is associated with medium and small artery changes. Patients with type 2 CTAO usually have multiple infarcts in the cerebral arterial border zones and may develop progressive cognitive decline without motor deficit. Her clinical features are compatible with type 2 CTAO. While CTAO is a relatively rare manifestation of Buerger's disease, it should be suspected in cases of Buerger's disease in association with cognitive impairment of unknown onset.


Assuntos
Infarto Cerebral/etiologia , Tromboangiite Obliterante/complicações , Feminino , Humanos , Pessoa de Meia-Idade
16.
Rinsho Shinkeigaku ; 44(1): 7-13, 2004 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-15199731

RESUMO

Paradoxical embolism through a patent foramen ovale (PFO) is a recognized cause of stroke, but its prognosis is not well known. The aim of our study is to evaluate differences in risk factors, recurrent stroke subtypes and effects of various preventive therapies between PFO associated stroke patients with and without deep vein thrombosis (DVT). A total of 63 patients who had an embolic stroke with a PFO within 3 months from stroke onset were enrolled. Venous ultrasonography, which was performed in all the patients, revealed DVT in 26 patients (41%). Venous thrombosis was confined to the isolated calf veins in 24 of 26 cases (92%). For prevention of stroke recurrence, warfarin was administrated in 32 patients, antiplatelet therapy was given in 21 patients, and combination of warfarin and antiplatelet therapy was chosen in 10 patients. Three patients with DVT and three other patients without DVT had recurrent ischemic events during a mean follow-up period of 14.6 months. In all the 3 patients without DVT, complicated aortic arch lesions were also observed, and 2 of them had lacunar infarcts. In all the three patients with DVT recurrent embolic stroke or TIA occurred in spite of anticoagulant therapy. Their INR values at the time of recurrence were all below 1.7, and 2 of them were associated with atrial septal aneurysm (ASA). Association with PFO, ASA, and DVT may be a substantial risk factor for recurrent stroke. Higher INR value in anticoagulation may be recommended for such patients to prevent stroke recurrence.


Assuntos
Comunicação Interatrial/complicações , Embolia Intracraniana/complicações , Acidente Vascular Cerebral/etiologia , Trombose Venosa/diagnóstico por imagem , Idoso , Anticoagulantes/uso terapêutico , Ecocardiografia Transesofagiana , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Acidente Vascular Cerebral/prevenção & controle , Trombose Venosa/diagnóstico , Varfarina/uso terapêutico
18.
Drugs R D ; 10(3): 155-63, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20945946

RESUMO

BACKGROUND AND OBJECTIVE: Stroke patients with severe leg paralysis are often bedridden in the acute and subacute phase, which increases the risk of disuse muscle atrophy in the chronic phase. The evidence to date indicates that oxidative stress plays an important role in the mechanism of disuse muscle atrophy. Therefore, the aim of this study was to determine if long-term radical scavenger treatment with edaravone following an acute stroke prevents the progression of disuse muscle atrophy and improves leg locomotor function in the chronic phase. METHODS: This randomized controlled pilot study was conducted at 19 acute stroke and rehabilitation centers across Japan. Forty-seven ischemic stroke patients with at least leg motor weakness admitted within 24 hours of onset were randomly assigned to receive continuous intravenous infusions of edaravone 30 mg twice daily for 3 days (short-term group) or 10-14 days (long-term group). The primary endpoints of the study included the degree of leg disuse muscle atrophy, as measured by the percentage change from baseline in femoral muscle circumference 15 cm above the knee, and the improvement in leg locomotor function, as assessed by the maximum walking speed over 10 m, 3 months after the onset of stroke. RESULTS: Three-month follow-up was completed by a total of 41 patients (21 in the short-term group and 20 in the long-term group). On admission, there was no significant difference in the severity of stroke or the grade of leg paresis between the two treatment groups. The grade of disuse muscle atrophy and incidence of gait impairment 3 weeks after stroke onset were also similar between the short- and long-term groups. However, disuse muscle atrophy of the paretic and non-paretic legs was significantly less severe in the long-term versus the short-term treatment group (3.6 ± 5.9% and 1.5 ± 6.0% vs 8.3 ± 5.2% and 5.7 ± 6.4%; p < 0.01 and p < 0.05) 3 months after stroke onset. Additionally, the maximum walking speed over a distance of 10 m was significantly greater in the long-term group (98 ± 67 vs 54 ± 55 cm/sec; p < 0.05). CONCLUSION: Edaravone treatment for up to 14 days suppresses the progression of disuse muscle atrophy and improves leg locomotor function to a greater extent than shorter-term treatment in acute stroke patients. This suggests that the management of stroke may be improved with long-term edaravone therapy by providing myoprotective effects that ameliorate functional outcome in the chronic phase.


Assuntos
Antipirina/análogos & derivados , Isquemia Encefálica/tratamento farmacológico , Sequestradores de Radicais Livres/uso terapêutico , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/prevenção & controle , Acidente Vascular Cerebral/tratamento farmacológico , Caminhada/fisiologia , Idoso , Antipirina/administração & dosagem , Antipirina/farmacologia , Antipirina/uso terapêutico , Isquemia Encefálica/complicações , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Esquema de Medicação , Edaravone , Feminino , Sequestradores de Radicais Livres/farmacologia , Humanos , Infusões Intravenosas , Perna (Membro)/patologia , Masculino , Atrofia Muscular/complicações , Paresia/tratamento farmacológico , Projetos Piloto , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/fisiopatologia
19.
Cerebrovasc Dis ; 21(5-6): 367-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16490949

RESUMO

BACKGROUND: Approximately one quarter of the acute ischemic stroke patients notice the event at awakening. Such patients with stroke at awakening are usually excluded from thrombolysis, since the time of stroke onset cannot be definitely identified. We compared the hyperacute CT findings of awakening stroke patients with those of stroke patients with known onset to assess whether the time of stroke onset is shortly before awakening. METHODS: Subjects were cardioembolic stroke patients who were consecutively admitted to our department within 3 h after the recognition of stroke during the period between January 2000 and March 2003. The patients were classified into three groups: group A with stroke of known onset, group B with stroke at awakening, and group C with stroke of unknown onset due to lack of a witness. The clinical and CT findings in each group were compared. RESULTS: A total of 81 patients fulfilled the study criteria. There were 46 patients in group A, 17 patients in group B, and 18 patients in group C. There was no significant difference in CT findings between groups A and B. In group C, however, definite hypodense areas were more commonly found than in group A (56 vs. 0%; p<0.001) or in group B (56 vs. 11%; p=0.012). CONCLUSION: Based on our CT findings, stroke at awakening seems to be developing shortly before in a large subset of patients, making them potential candidates for acute stroke therapies.


Assuntos
Embolia Intracraniana/diagnóstico por imagem , Sono , Acidente Vascular Cerebral/diagnóstico por imagem , Vigília , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Embolia Intracraniana/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Tomografia Computadorizada por Raios X
20.
Cerebrovasc Dis ; 21(1-2): 26-31, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16282686

RESUMO

BACKGROUND AND PURPOSE: Severe atheroma >or=4 or 5 mm of the aortic arch is a risk factor for stroke. We investigated the most predictive characteristics of arch atheroma, including maximal plaque thickness, for subsequent cardiovascular events, and also examined whether moderate atheroma<4 mm is a risk of cerebral emboli. METHODS: The maximal plaque thickness (MPT) and plaque morphologies of the aortic arch were evaluated by transesophageal echocardiography in 236 patients with ischemic stroke. We assessed the relationship between the incidence of cardiovascular events, recurrent stroke or myocardial infarction, and the characteristics of the atheroma. We also investigated the thickness of atheroma in patients with known causes of stroke (n=148) and in patients with undetermined causes (n=19). RESULTS: Cardiovascular events occurred in 47 patients in the follow-up period with a mean of 3.5 years. MPT was a significant risk factor of the cardiovascular events, although plaque morphologies were not. For the receiver operator characteristics curve analysis, the suitable cutoff point of MPT associated with the cardiovascular events was 3.5 mm. Patients with MPT >or=3.5 mm had a higher risk of cardiovascular events than did those with MPT<3.5 mm. In addition, aortic atheroma with MPT >or=3.5 mm was more frequently observed in patients with undetermined causes of stroke than those with known causes at 68 vs. 39% (p=0.024). CONCLUSIONS: MPT >or=3.5 mm is the best predictor of subsequent cardiovascular events and a possible cause of embolic stroke.


Assuntos
Aorta Torácica , Aterosclerose/complicações , Aterosclerose/patologia , Isquemia Encefálica/etiologia , Embolia Intracraniana/etiologia , Acidente Vascular Cerebral/etiologia , Idoso , Aterosclerose/diagnóstico por imagem , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA