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Masanori Nakagawa

Publications and source records attributed to Masanori Nakagawa.

At least 19 recordsLinked to original sources
PubMed2006

Cognitive impairment and frontal-subcortical geriatric syndrome are associated with metabolic syndrome in a stroke-free population.

BACKGROUND: Metabolic syndrome (Met.S) consists of a conglomeration of obesity, hypertension, glucose intolerance, and dislipidemia. Frontal-subcortical geriatric syndrome (FSCS) is caused by ischemic disruption of the frontal-subcortical network. It is unknown if Met.S is associated with FSCS. METHODS: We evaluated 422 community-dwelling elderly (> or =60) in Brazil. FSCS was defined as the presence of at least one frontal release sign (grasping, palmomental, snout, or glabellar) plus coexistence of > or =3 the following criteria: (1) cognitive impairment, (2) late-onset depression, (3) neuromotor dysfunction, and (4) urgency incontinence. All values were adjusted to age and gender. RESULTS: Met.S was present in 39.3% of all subjects. Cases without any of the FSCS components represented 37.2% ('successful neuroaging' group). People with 1-3 of the FSCS components ('borderline pathological neuroaging' group) were majority (52.6%), whereas those with 4-5 of these components (FSCS group) were minority (10.2%). Met.S was significantly associated with FSCS (OR=5.9; CI: 1.5-23.4) and cognitive impairment (OR=2.2; CI: 1.1-4.6) among stroke-free subjects. Number of Met.S components explained 30.7% of the variance on the number of FSCS criteria (P<0.001). If Met.S were theoretically removed from this population, prevalence of FSCS would decline by 31.6% and that of cognitive impairment by 21.4%. CONCLUSIONS: Met.S was significantly associated with a 5.9 and 2.2 times higher chance of FSCS and cognitive impairment, respectively. Met.S might be a major determinant of 'successful' or 'pathological' neuroaging in western societies.

Aged↗
PubMed2006

Decreased alpha-synuclein in cerebrospinal fluid of aged individuals and subjects with Parkinson's disease.

There is ample biochemical, pathological, and genetic evidence that the metabolism of alpha-synuclein (alpha-syn) plays a crucial role in the pathogenesis of Parkinson disease (PD). To examine whether quantification of alpha-syn in cerebrospinal fluid (CSF) is potentially informative in the diagnosis of PD, we developed a specific ELISA system and measured the concentration of alpha-syn in CSF from 33 patients with PD (diagnosed according to UK PD Society Brain Bank criteria) and 38 control subjects including 9 neurologically healthy individuals. We found that PD patients had significantly lower alpha-syn levels in their CSF than the control groups (p<0.0001) even after adjusting for gender and age. Age was independently associated with lower alpha-syn levels. Logistic regression analysis showed that reduction in CSF alpha-syn served as a significant predictor of PD beyond age and gender alone (area under ROC curve, c=0.882). Furthermore, we observed a close inverse correlation between alpha-syn levels in CSF and assigned Hoehn and Yahr score in this cohort of 71 living subjects (p<0.0001), even after adjusting for age. These findings identify in the quantification of alpha-syn from CSF a potential laboratory marker to aid the clinical diagnosis of PD.

Adolescent↗
PubMed2006

Molecular mechanism of rigid spine with muscular dystrophy type 1 caused by novel mutations of selenoprotein N gene.

Mutations of selenoprotein N, 1 gene (SEPN1) cause rigid spine with muscular dystrophy type 1 (RSMD1), multiminicore disease, and desmin-related myopathy. We found two novel SEPN1 mutations in two Japanese patients with RSMD1. To clarify the pathomechanism of RSMD1, we performed immunohistochemical studies using a newly developed antibody for selenoprotein N. Selenoprotein N was diffusely distributed in the cytoplasm of the control muscle, but was reduced and irregularly expressed in the cytoplasm of a patient with RSMD1. The expression pattern was very similar to that of calnexin, a transmembrane protein of the endoplasmic reticulum. Selenoprotein N seems to be an endoplasmic reticulum glycoprotein, and loss of this protein leads to disturbance of muscular function. One of the families had the SEPN1 homozygous mutation in the initiation codon 1_2 ins T in exon 1 and showed truncated protein expression. The other had a homozygous 20-base duplication mutation at 80 (80_99dup, frameshift at R27) which, in theory, should generate many nonsense mutations including TGA. These nonsense mutations are premature translation termination codons and they degrade immediately by the process of nonsense-mediated decay (NMD). However, truncated selenoprotein N was also expressed. A possible mechanism behind this observation is that SEPN1 mRNAs may be resistant to NMD. We report on the possible molecular mechanism behind these mutations in SEPN1. Our study clarifies molecular mechanisms of this muscular disorder.

Adult↗
PubMed2006

Microbleeds in Alzheimer disease are more related to cerebral amyloid angiopathy than cerebrovascular disease.

Cerebral amyloid angiopathy (CAA) is one of the cardinal pathological features in the vascular components of Alzheimer's disease (AD). CAA itself results in disrupted microvasculature, mainly in the cerebral cortex, eventually leading to a brain cortical or subcortical hemorrhage in a population of elderly people, but clinically overt brain hemorrhages are not so frequent in AD patients. Here we assessed 50 AD patients and 26 controls to detect latent brain hemorrhages with gradient-echo T(2)*-weighted images, a sensitive magnetic resonance imaging technique to detect hemosiderin components in the brain. Microbleeds, demarcated as low-intensity spots in T(2)*-weighted images, were detected in 16.7% of AD patients without cerebrovascular disease (CVD) and in 12.5% of those with CVD, while no microbleeding was detected in the control subjects. No significant difference was observed between the microbleed-positive group and the microbleed-negative counterpart in their clinical background, such as hypertension, the use of antiplatelet drugs and smoking. In addition, white matter high intensities in the T(2)-weighted image were significantly more confluent in the microbleed-positive AD group than its negative counterpart. In conclusion, our evaluation of AD brains revealed that latent microbleeds in AD patients are more frequent than in normal controls. Microbleeds not being related to common hemorrhagic risk factors, but being significantly related to white matter pathologies suggested that microbleeds in AD may be associated with CAA, but not with hypertension or CVD.

Aged↗
PubMed2006

Oculomotor nerve palsy evaluated by diffusion-tensor tractography.

INTRODUCTION: The aim of the study was to test the feasibility of the tractography technique based on diffusion-tensor imaging (DTI) for the assessment of small infarcts involving the brainstem. METHODS: A patient who presented with an isolated left third cranial nerve palsy underwent magnetic resonance examination. Images were obtained by use of a whole-body, 1.5-T imager. Data were transferred to an off-line workstation for fiber tracking. RESULTS: The conventional diffusion-weighted imaging (DWI) performed using a 5 mm slice thickness could only depict an equivocal hyperintensity lesion located at the left paramedian midbrain. An additional thin-slice DTI was performed immediately after the initial DWI using a 3 mm slice thickness and was able to delineate the lesion more clearly. Image postprocessing of thin-slice DTI data revealed that the lesion location involved the course of the third cranial nerve tract, corresponding with the patient's clinical symptoms. CONCLUSION: The tractography technique can be applied to assess fine neuronal structures of the brainstem, enabling direct clinicoradiological correlation of small infarcts involving this region.

Aged↗
PubMed2006

Anaplastic astrocytoma presenting as reversible posterior leukoencephalopathy syndrome.

We report a 60-year-old man with grade III astrocytoma, who presented with status epilepticus. The initial MRI did not demonstrate typical findings of an astrocytoma but rather showed reversible posterior leukoencephalopathy syndrome (RPLS). N-Isopropil-p-[I] iodoamphetamine single photon emission computed tomography (SPECT) demonstrated hyperperfusion in this area. A brain tumor should be considered and the patient carefully followed by MRI, even if the MRI white matter lesion pattern suggests RPLS. This is especially relevant in the presence of atypical findings for RPLS on SPECT.

Astrocytoma↗
PubMed2006

Toenail arsenic levels among residents in Amami-Oshima Island, Japan.

In order to evaluate the current arsenic exposure status and its determinants in Japan, we collected toenail samples from 212 subjects residing in a town with a population of 6,900 in Amami-Oshima Island in August 1999. We measured arsenic concentrations of the toenails using inductively coupled plasma mass spectrometry. In addition, we examined the association of arsenic levels with lifestyles and dietary habits, including the consumption of fish, seaweed, and rice. The mean toenail arsenic level was 0.41 ppm (95% confidence interval, 0.36-0.47), which was about 3-fold higher than those observed in other populations of mainland Kagoshima. Arsenic levels were elevated among current smokers (mean = 0.65; 95% confidence interval, 0.32-1.29) when compared with non-smokers (mean = 0.40; 95% confidence interval, 0.34-0.46), and among the residents consuming 4 bowls or more, of rice every day (mean = 1.97; 95% confidence interval, 0.25-15.75) when compared to residents consuming 3 bowls or less (mean = 0.39; 95% confidence interval, 0.34-0.45). Sex, age, alcohol intake, fish consumption, or seaweed consumption was not associated with toenail arsenic concentration. Further studies seem warranted to examine the cause of relatively high arsenic levels in our study area.

Aged↗
PubMed2006

[A case of amyotrophic lateral sclerosis presenting as motor aphasia in its early stage].

A 76-year-old right-handed woman complained of speech disturbance and difficulity of singing was admitted to our hospital. Examination showed motor aphasia and mild cognitive impairment. After she was discharged, dementia and weakness of the extremities had rapidly progressed. She was readmitted eight month after the first visit, when she was almost abulic, her skeletal and bulbar muscles were remarkably atrophic, and hyperreflexia of the extremities were seen. Electromyographcal study showed neurogenic pattern. These findings suggest amyotrophic lateral sclerosis (ALS) with dementia. Pathological findings were atrophy at the anterior horn of the spinal cord. The brain was diffusely atrophic. The extent of degenerative change was not lateralized. This case is a discriminative type of ALS with dementia, that its first symptom is motor aphasia.

Aged↗
PubMed2005

Autosomal dominant leukodystrophy with axonal spheroids and pigmented glia: clinical and neuropathological characteristics.

We report two autopsy cases of siblings with adult-onset autosomal dominant leukodystrophy characterized by destruction of cerebral white matter, large numbers of axonal spheroids and pigmented glia in the fronto-temporal lobes. Both patients presented with motor and cognitive symptoms and aphasia, 2-3 years before death. At autopsy, the brain showed brown coloration and decreased volume of white matter in the frontal and temporal lobes as well as corpus callosum. Microscopically, marked loss of myelin and axons and abundant axonal spheroids without apparent neuronal loss were observed in the frontal and temporal lobes, which was consistent with hereditary diffuse leukodystrophy with spheroids (HDLS). In addition, glial cells, most consistent with macrophages and containing pigments that were stained by Sudan III and PAS, were found in the white matter lesions. The present cases showed overlapping features with HDLS and pigmentary type of orthochromatic leukodystrophy, suggesting that the pathomechanisms of these two diseases are closely related.

Axons↗
PubMed2005

Autonomic nervous evaluation in the early stages of olivopontocerebellar atrophy.

The clinical significance of evaluating autonomic nervous system functions in the early stages of olivopontocerebellar atrophy (OPCA) has been investigated in 13 OPCA out-patients (7 males and 6 females, mean age: 51.0 years). We have employed measurements of blood pressure, plasma norepinephrine (NE), CVR-R, low-frequency power/high-frequency power ratio (L/H), high-frequency power (HF) score and heart rate (HR) monitoring using Holter ECG recording for evaluation of CVR-R. We have also carried out urodynamic examinations, focusing on the possible existence of bladder dysfunction. Although no significant changes were noted between control and OPCA groups concerning HR, CVR-R, L/H, plasma levels of norepinephrine and systolic blood pressure, HF (high-frequency power) (ms(2)), especially at night time, invariably showed a significant decline in OPCA groups. All OPCA patients who showed a decreased circadian HF also exhibited a tendency towards urinary bladder dysfunction. The present results appear to relate to disorder of the parasympathetic autonomic nervous system and neuromuscular dysfunction in the lower urinary tract. In conclusion, HRV (heart rate variability) analysis is a useful and safe tool and a keen predictor for evaluating functional states of autonomic nervous activity, especially in the early stages of OPCA. This study has also suggested the possible efficacy of urodynamic measurements in OPCA patients as an indicator of neuromuscular dysfunction in the lower urinary tract and of parasympathetic malfunction.

Adult↗
PubMed2005

Local tissue anisotropy decreases in cerebellopetal fibers and pyramidal tract in multiple system atrophy.

BACKGROUND: One of the cardinal features in multiple system atrophy (MSA) is the white matter pathology: loss of myelin, astrocytosis, and glial cytoplasmic inclusions. The pathological changes of tissue microstructure can modify the diffusion behavior of water molecules, which can be assessed by diffusion tensor imaging (DTI). OBJECTIVES: To explore the hypothesis of white matter degeneration in MSA. METHODS: We studied 11 patients with clinically probable MSA and 10 age-matched controls. DTI was performed in both groups to measure fractional anisotropy (FA) in various regions of interest: the inferior cerebellar peduncle (ICP), middle cerebellar peduncle (MCP), superior cerebellar peduncle (SCP), basis pontis, internal capsule, and corpus callosum. RESULTS: FA values in SCP and corpus callosum showed no significant difference between the MSA group and controls. By contrast, FA values decreased in the MSA group in the MCP, basis pontis and internal capsule. In addition, FA values in the MCP were negatively correlated with ataxia severity in the MSA group. CONCLUSION: The areas showing decreased tissue anisotropy in DTI corresponded well with pathologically vulnerable areas in MSA. In addition, the local tissue anisotropy of MCP decreased in accordance with functional disability. These observations implied that DTI is a feasible method for in vivo evaluation of the white matter pathology in MSA.

Aged↗
PubMed2005

Discrepancy between clinical and pathological diagnoses of CBD and PSP.

Progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD) are often clinically confused with each other. Moreover, the discrepancy between clinical and pathological diagnoses of CBD and PSP are still controversial. We report here two atypical cases of PSP and CBD. A 73-year old woman was admitted with right hand rigidity, limb kinetic apraxia and cortical sensory loss. Brain atrophy, hypoperfusion and hypometabolism predominantly in the left frontoparietal lobes indicated CBD clinically. Pathological studies revealed neuronal loss and spongy change without ballooned neurons (BN) in the cerebral cortex. Modified Gallyas-Braak (G-B) staining revealed neurofibrillary tangles (NFTs) and tufted astrocytes, indicating pathological diagnosis of PSP. A 75-year-old man admitted with vertical gaze palsy, neck dystonia, parkinsonism and dementia. Atrophy of the frontal lobes and tegmentum of the midbrain and symmetrical frontal hypoperfusion in SPECT indicated PSP. However, neuronal loss and BN in the frontal lobes and clusters of astrocytic plaques indicated CBD pathologically. The G-B staining was useful for differentiating between CBD and PSP, but our atypical cases bring up a new issue about differential diagnosis of CBD and PSP.

Aged↗
PubMed2005

The severity of Minamata disease declined in 25 years: temporal profile of the neurological findings analyzed by multiple logistic regression model.

Minamata disease (MD) was caused by ingestion of seafood from the methylmercury-contaminated areas. Although 50 years have passed since the discovery of MD, there have been only a few studies on the temporal profile of neurological findings in certified MD patients. Thus, we evaluated changes in neurological symptoms and signs of MD using discriminants by multiple logistic regression analysis. The severity of predictive index declined in 25 years in most of the patients. Only a few patients showed aggravation of neurological findings, which was due to complications such as spino-cerebellar degeneration. Patients with chronic MD aged over 45 years had several concomitant diseases so that their clinical pictures were complicated. It was difficult to differentiate chronic MD using statistically established discriminants based on sensory disturbance alone. In conclusion, the severity of MD declined in 25 years along with the modification by age-related concomitant disorders.

Adolescent↗
PubMed2005

[Prognosis of patients with myasthenia gravis].

AIM: To study the correlation between therapy and outcome of patients with late adult onset and ocular type myasthenia gravis (MG). METHODS: The 58 MG patients admitted to our hospitals from 1991 to 2003 were classified into juvenile (younger than 20), early adult onset (20-64) and late adult onset (65 or older) groups, or also ocular and generalized types. We evaluated their therapeutic outcomes. RESULTS: The late adult onset group consisted of 11 patients, classified as 4 ocular and 7 generalized types. There were more women than men in both the late and early adult onset groups. Anti-acetylcholine receptor (anti-AchR) antibodies were positive in all patients. Four patients had thymus lesions. Ten patients received treatment as follows: steroid therapy in 6, thymectomy in 4 and only choline-esterase (ChE) inhibitor therapy in 4 patients. However 4 patients worsened after treatment because of inadequate steroid therapy, 2 of whom experienced myasthenic crisis. On the other hand 21 patients were ocular type, of whom anti-AchR antibodies were positive in 12. They received treatments of the 21, steroid therapy was given to 12, thymectomy was performed in 4 and only ChE inhibitor therapy was given to 8 patients. One ocular type patient progressed to the generalized type. Six of 16 improved patients showed distinct recovery. CONCLUSION: In the late adult onset group careful assessment concerning timings of administration and reduction of steroid are required to avoid side effects and complications. One ocular type patient progressed to the generalized type and most patients had a good outcome, which might be related to steroid therapy.

Adult↗
PubMed2005

[Clinical classification for lacunar infarct. An investigation of 130 consecutive cases of lacunar infarctions].

A lacunar infarct is defined as the occlusion of a single perforating artery. Certain researchers have proposed that patients with lacunar infarcts can be classified into two clinically distinct entities: patients with a single, symptomatic lacunar infarct, and patients with multiple lacunar infarcts together with hypertension and leukoaraiosis. The present study attempted to delineate the characteristics of lacunar infarcts and evaluate the validity of the aforementioned hypothesis. A total of 130 consecutive patients with first-time symptomatic lacunar infarct were studied. All patients were dichotomized into two groups according to two different kinds of models as follows. Model-1: patients with a single lacune and patients with multiple lacunes; and Model-2: patients with large lacune and patients with small lacune. Associated factors for the multiple lacune group compared with the single lacune group as well as the large lacune group compared with the small lacune group, were analyzed by multivariate logistic regression analysis. Associated factors included age, sex, hypertension, diabetes mellitus, dyslipidemia, smoking, extracranial and intra-cranial vascular lesions, extent of lacunes and white matter lesions, progression status and blood pressure in the acute stage, and coagulation markers such as fibrinogen, thrombin-antithrombin complex, D-dimer, beta-thromboglobulin, platelet factor 4. Results for Model-1: hypertension (age-and sex-adjusted OR: 2.58, p = 0.017) and elevated systolic blood pressure (>160mmHg for the mean value during the first post-ictal week; OR: 2.55, p = 0.016) were significantly associated with the multiple lacune group. Large lacunes (>10mm in diameter) were negatively associated with the multiple lacune group (OR: 0.38, p = 0.017). Association between confluent white matter lesions and the multiple lacune group approached significance (OR: 2.16, p = 0.056). Results for Model-2: female sex (OR: 0.39, p = 0.021), mild stenosis of intracranial and extracranial arteries (<25%) (intracranial; OR: 5.42, p = 0.0042, extracranial; OR: 3.30, p = 0.016), progressing stroke (OR: 6.77, p<0.0001), and high levels of TAT (>3ng/ml) (OR: 2.80, p = 0.039) were significantly associated with the large lacune group. Multiple lacunes (OR: 0.38, p = 0.016) and confluent white matter lesions (OR: 0.28, p = 0.007) exhibited a significant negative association with the large lacune group. In conclusion, underlying vasculopathy in the presence of multiple lacunes may correspond to lipohyalinosis resulting from hypertension. Moreover, large lacune may correspond to microatheroma at the orifice of penetrating arteries.

Aged↗
PubMed2005

Effect of thin-section diffusion-weighted MR imaging on stroke diagnosis.

BACKGROUND AND PURPOSE: Diffusion-weighted (DW) imaging has limited spatial resolution, especially in the z direction. We decreased the section thickness of DW imaging to 3 mm to determine if this change improves the depiction of small infarcts and if it affects stroke diagnosis. METHODS: We studied conventional (5-mm section thickness, 1-mm intersection gap) and thin-section (3-mm section thickness, no intersection gap) DW imaging data in 49 patients with symptoms of acute cerebral ischemia. Two radiologists who were not aware of the clinical findings reviewed all images and diagnosed the stroke subtype according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) method. Accuracies of stroke diagnosis with an experienced neuroradiologist and with a second-year radiology resident were compared. To quantify lesion conspicuity, contrast-to-noise ratios (CNRs) were measured. The CNR of thin-section DW imaging was then divided by the CNR of conventional DW imaging to yield the relative CNR (rCNR). RESULTS: The experienced neuroradiologist made the correct final diagnoses in 78% of cases with conventional DW imaging, improving to 100% with thin-section DW imaging. The resident made the correct diagnoses in 71% of cases with conventional DW imaging, improving to 94% with thin-section DW imaging. Lesion conspicuity was improved on thin-section DW imaging (rCNR = 1.47 +/- 0.63), especially for supratentorial lesions (rCNR = 1.51 +/- 0.63). CONCLUSION: Compared with conventional DW imaging, thin-section DW imaging permitted better lesion conspicuity and more precise stroke diagnosis.

Aged↗
PubMed2005

Neuro-Behçet disease mimicking brain tumor.

Neuro-Behcet disease is one of the clinical forms of Behcet disease. We report a case of neuro-Behcet disease mimicked a brain tumor. This case was initially considered as a brain tumor from mass lesion with edema at left basal ganglia on radiologic images. The lesion, however, was not neoplasia by pathologic diagnosis. By using steroid therapy, the size had been markedly shrunken on the follow-up images. The clinical symptoms were also improved.

Adult↗