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Shigeki Kuzuhara

Publications and source records attributed to Shigeki Kuzuhara.

At least 19 recordsLinked to original sources
PubMed2006

Frontotemporal lobar degeneration with ubiquitin pathology: an autopsy case presenting with semantic dementia and upper motor neuron signs with a clinical course of 19 years.

We report a case of a right-handed 74-year-old man who showed semantic dementia with a disease duration of 19 years. He initially presented with excessive use of pronouns and semantic paraphasia at the age of 55 years. Impairment of object recognition developed 5 years after the onset. Face recognition impairment and stereotypic behaviors developed 11 years after onset, and pyramidal signs 2 years before death. Pathological examination disclosed circumscribed severe atrophy in not only the bilateral temporal tips but also in the left precentral gyrus and pars opercularis in a motor speech field. Pyramidal tract involvement and loss of Betz cells were also evident. On the other hand, neurons in the anterior horns and hypoglossal nuclei were spared in number, although astrocytes were mildly proliferated. Ubiquitin-positive lesions were observed in the hippocampus, and frontal and temporal cortices. Neither Bunina bodies nor Pick bodies were present. These features clinically fit the international diagnostic criteria of semantic dementia and, histopathologically, frontotemporal lobar degeneration with motor neuron disease (FTLD-MND). This case suggests that (1) the distribution of cortical lesions associated with language disturbance is not uniform in FTLD-MND. It may be that only some cases of FTLD with ubiquitin pathology develop semantic dementia despite the high incidence of language disturbance, and (2) the precentral gyrus can be severely affected in FTLD-MND. After reviewing previous cases of FTLD-MND with a clinical course of more than 10 years, we also noticed that (3) FTLD-MND cases with a long disease duration often show upper motor neuron-predominant involvement.

Age of Onset↗
PubMed2006

Four mutations of the spastin gene in Japanese families with spastic paraplegia.

Hereditary spastic paraplegia (HSP) is a group of genetically heterogeneous neurodegenerative disorders characterized by slowly progressive spasticity and weakness of the lower limbs. HSP is caused by failure of development or selective degeneration of the corticospinal tracts, which contain the longest axons in humans. The most common form of HSP is caused by mutations of the spastin gene (SPAST), located on chromosome 2p21-p22, which encodes spastin, one of the ATPases associated with diverse cellular activities (AAA). In this study, we detected four causative mutations of SPAST among 14 unrelated patients with spastic paraplegia. Two missense mutations (1447A-->G, 1207C-->G) and two deletion mutations (1465delT, 1475-1476delAA) were located in the AAA cassette region. Three of these four mutations were novel. Previous reports and our results suggest that the frequency of SPAST mutations is higher among Japanese patients with autosomal dominant HSP, although SPAST mutations are also observed in patients with sporadic spastic paraplegia.

Adenosine Triphosphatases↗
PubMed2006

Clinical evaluation of plasma free phenytoin measurement and factors influencing its protein binding.

The relationship between free phenytoin concentrations and clinical responses, and the factors influencing protein binding of phenytoin were investigated. A total of 119 plasma samples from 70 patients treated orally with phenytoin were analysed. The mean free phenytoin concentration was significantly higher in the patients who received phenytoin monotherapy and were classified as having a complete response (1.25 +/- 1.09 microg/ml) than that in the partial response group (0.59 +/- 0.07 microg/ml), whereas the mean total concentrations were not significantly different between the two groups. Samples were divided into three groups based on the free fraction of phenytoin, i.e. low, <5%; medium, 5%-10%; high, > 10%. The mean age (55.3 +/- 10.9 years) was significantly higher in the high group than in the low (42.7 +/- 21.2 years) and medium (42.8 +/- 16.0 years) groups. The mean creatinine clearance (CLcr) (55.3 +/- 10.9 ml/min) and serum albumin concentration (3.30 +/- 1.25 g/dl) were significantly lower in the high group than the low (88.3 +/- 29.0 ml/min and 4.08 +/- 0.50 g/dl, respectively) and medium (95.0 +/- 32.8 ml/min and 3.95 +/- 0.92 g/dl, respectively) groups. These results suggest that the free phenytoin concentration, rather than the total concentration, is more useful for monitoring antiepileptic effects in patients receiving phenytoin monotherapy. It was also found that the free phenytoin fraction was significantly influenced by aging, CLcr and serum albumin levels.

Adolescent↗
PubMed2006

[Correlation of the cognitive function and the duration of the illness with the regional cerebral blood flow in the patients with Parkinson's disease: objective evaluation using stereotactic extraction estimation analysis in 123I-IMP SPECT].

OBJECTIVE: To investigate the correlation of the cognitive function and the duration of the illness with the regional cerebral blood flow (rCBF) in patients with Parkinson's disease (PD), by means of an objective diagnostic index of brain imaging, stereotactic extraction estimation (SEE) of 123I-IMP SPECT. PATIENTS AND METHODS: We examined 123I-IMP SPECT in 24 patients with PD (age = 71.79 +/- 5.18 years; the Mini-Mental State Examination: MMSE score = 21.46 +/- 7.62 points; the duration of the illness = 6.63 +/- 3.91 years; Yahr scale = 3.29 +/- 0.74). A contrast database was created by averaging extracted database sets of the contrast group (numbers = 14 cases; age = 74.64 +/- 5.99 years, the MMSE score > or = 29 points). We applied SEE for Z-score images of three-dimensional stereotactic surface projection analysis (3D-SSP) for 123I-IMP SPECT, and calculated Z*extent ratio by taking advantage of severity of Z-score (the mean value) with extent ratio (%) in the frontal, occipital, temporal, parietal and posterior cingulate cortices, and precuneus, respectively. We investigated the correlation coefficient between the MMSE score and Z*extent ratio, and between the duration of the illness and Z*extent ratio in the six regions. In addition, we compared Z*extent ratio in the six regions between the non-demented group (numbers = 12 patients; MMSE > or = 24 points) and the demented group (numbers =12 patients; E score < or = 23 points). RESULTS: There were negative correlations between the MMSE score and Z*extent ratio in the temporal (p < 0.05) and posterior cingulate cortices (p < 0.05), and positive correlations between the duration of the illness and Z*extent ratio in the frontal (p < 0.01), temporal (p < 0.01), parietal (p < 0.05) and posterior cingulate cortices (p < 0.01). Z*extent ratio was significantly high only in the posterior cingulate cortex(p < 0.05) in the demented group. CONCLUSIONS: SEE for Z-score images of 3D-SSP revealed a close relationship between the decline of the MMSE score and the duration of the illness, and the perfusion reduction of the posterior cingulate cortex in patients with PD. These findings suggest that the perfusion reduction of the posterior cingulate cortex reflects the decline of cognitive impairment of patients with PD.

Aged↗
PubMed2006

[Diffusion-weighted magnetic resonance imagings at the acute stage in two patients with spectacular shrinking deficit due to cardioembolic stroke].

We report diffusion-weighted magnetic resonance imagings (DWI) at the acute stage of two patients with spectacular shrinking deficit (SSD) due to cardioembolic stroke. Patient 1 was a 74-year-old woman with atrial fibrillation (Af) who had been admitted for acute cholecystitis. She abruptly developed consciousness disturbance, global aphasia and right hemiparesis. Her neurological symptoms rapidly improved 30 minutes after onset, and completely disappeared in four hours. Patient 2 was a 84-year-old woman with Af who had been on medication of warfarin potassium for three years. She abruptly developed consciousness disturbance and left hemiplegia. Her neurological symptoms rapidly improved 90 minutes after onset, and almost completely disappeared in ten hours. Their conditions were consistent with SSD in acute cardioembolic stroke. DWI of Patient 1 taken 27 hours after onset showed hyperintense signal areas in the insular and temporal cortices of the left middle cerebral artery territory, and in the parietal cortex corresponding to the border zone between the territories of the left middle cerebral artery and posterior cerebral artery. DWI of Patient 2 taken 39 hours after onset showed hyperintense signal areas in the insular and frontal cortices of the right middle cerebral artery territory, and in the parietal cortex corresponding to the border zone between the territories of the right middle cerebral artery and posterior cerebral artery. They indicated multifocal ischemic injuries at the acute stage. The T2-weighted MRI of Patient 2 showed a slight hyperintense signal area only in the right parietal cortex, but the fluid-attenuated inversion recovery (FLAIR) in both patients showed no abnormal signals in the corresponding areas. To our knowledge, ischemic lesions in DWI of SSD at the acute stage after rapid recovery have not been reported previously. DWI is useful in SSD for detecting ischemic injuries of cardioembolic origin at the early stage.

Aged↗
PubMed2006

[The most probable clinical diagnosis to the applicants for the intractable disease registration of Parkinson's disease, spinocerebellar degeneration and amyotrophic lateral sclerosis].

Amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD) and spinocerebellar degeneration (SCD) are included in the 45 intractable diseases" acknowledged by the Ministry of Health, Labour and Welfare of Japan. The registration of applicants is based on the attending doctors' diagnosis, and medical costs of registered patients are covered by the government. However, the accuracy of the diagnoses has not been investigated previously. The aim of the present study is to investigate the accuracy of the diagnoses of patients registered as PD, SCD and ALS in Mie prefecture of Japan. The study design was cross-sectional and the survey was carried out using an anonymous questionnaire. We asked the attending doctors the most probable clinical diagnosis in each applicant for PD, SCD or ALS at the annual renewal of application form of the specified diseases by the Ministry. The questionnaires were sent to the 57 neurologists in 20 general hospitals and 2 neurology clinics in Mie prefecture, Japan. The survey was carried out from July to September, 2003. For each disorder (PD, ALS, SCD), the accuracy rates were calculated as the ratio of the number of patients with the most probable diagnosis of the consistent disease to the number of all patients registered each disease. Questionnaires on 678 patients replied from 31 neurologists, 27 of whom were the neurology specialists approved by the Japanese Society of Neurology, were retrieved and analyzed. They covered 41.1% of the total registered PD cases, 45.4% of total SCD cases, and 54.0% of total ALS cases in Mie prefecture. The final clinical diagnosis were made by such specialists in 641 cases (94.5%). The accuracy rate of PD was 97.3% for all degenerative parkinsonisms and 90.2% for idiopathic PD, 96.0% for SCD, and 77.8% for typical ALS and 81.5% for ALS and Kennedy-Alter-Sung syndrome. Although the most probable diagnoses were performed by the attending physicians without verification by other raters, the accuracy rates were excellently high in these diseases, partly because most of the attending physicians were neurology specialists. The relatively low accuracy rate in ALS may be caused partly by the difficulty in differentiating it from spine diseases, neuropathies or myopathies at the early stage of the disease when the patients had been registered, or by inclusion of other motor neuron diseases such as Kennedy-Alter-Sung syndrome.

Amyotrophic Lateral Sclerosis↗
PubMed2005

Atypical parkinsonism of Japan: amyotrophic lateral sclerosis-parkinsonism-dementia complex of the Kii peninsula of Japan (Muro disease): an update.

An update of the endemic parkinsonism-dementia complex (PDC) frequently associated with amyotrophic lateral sclerosis (ALS) in the high prevalence ALS focus of the Kii peninsula of Japan is presented. The initial symptom was parkinsonian gait or hypobulia/amnesia, which was followed by akinesia, rigidity, occasional tremor, bradyphrenia, abulia and amnesia, and finally by akinetic mutism. In several years, most of the patients developed ALS symptoms such as muscle atrophy, bulbar palsy, and upper motor neuron signs. Magnetic resonance imaging and computed tomography of the brain showed marked atrophy of the temporal and frontal lobes and the cerebral blood flow reduction on single-photon emission computed tomography. Marked loss of nerve cells associated with abundant neurofibrillar tangles (NFTs) in the entire central nervous system, most predominantly in the brainstem and temporal lobe was characteristic. Concomitant ALS pathology involving the upper and lower motor neurons was common, and senile plaques were absent in most cases. NFTs consisted of twisted tubules on electron microscopy. Western blot of tau protein showed three bands consisting of six tau isoforms, similar to those of Alzheimer's disease. A family history of ALS/PDC was recorded in more than 70% of patients, but no abnormal mutation or polymorphism was found in the genes of SOD1, tau, and apolipoprotein E. Familial nature and continuing morbidity of Kii ALS/PDC suggest that genetic factors may be more likely in its pathogenesis.

Aged↗
PubMed2005

A case of amusia caused by the infarction of anterior portion of bilateral temporal lobes.

It remains an unsettled question which brain regions participate in music perception. During singing a familiar song, the retrieval from long-term memory is necessary, but the mechanism of that retrieval is still unclear. We carried out a detailed examination of musical ability in a patient with amusia and control subjects and identified the lesion sites of our patient using MRI. Compared with controls, the patient manifested the following impairments in music perception: (i) the recognition and discrimination of familiar melodies; (ii) the discrimination of unfamiliar phrases; (iii) the discrimination of isolated chords. During singing familiar nursery songs, the patient showed the replacement of one phrase of the melody. In MRI, the patient had old infarction in the anterior portion of the temporal lobes bilaterally. In conclusion, the anterior temporal lobes participate in the perception and expression of music. During singing, the song is retrieved from long-term memory by a unit of one phrase. The dysfunction of that retrieval caused the replacement of the succeeding phrases of the original with the wrong tune, and we named this phenomenon paramelodia.

Aged↗
PubMed2005

[Iatrogenic neurological disorders in old people: a review].

Aged people are frequently the victims of iatrogenic diseases, especially adverse effects of drugs since they are affected by many age-related diseases and are given many drugs. Geriatric medicine in Japan has a bitter history of having produced many victims by adverse effects of cerebral vasodilators and cerebral stimulants; they included parkinsonism and depression induced by flunarizine and cinnarizine, and Reye-like encephalopathy induced by calcium hopantenate. Parkinsonism induced by sulpiride, tiapride, metoclopramide or atypical anti-psychotics, dyskinesia induced by anti-parkinsonian drugs or anti-psychotics, and psychotic symptoms induced by anti-parkinsonian drugs, anti-cholinergic drugs, anti-depressants or histamine H2 antagonists are still very common. Wernicke encephalopathy caused by intravenous glucose infusion without thiamine, central pontine myelinolysis by too rapid correction of hyponatremia are important though infrequent. Iatrogenic Creutzfeldt-Jakob disease by dura grafts is a warning against the easy use of medical materials produced with human organs or blood. Iatrogenic diseases are preventable, and geriatricians have to pay attention to the information on adverse effects of drugs and medical materials and carefully observe the early signs of iatrogenic diseases.

Aged↗
PubMed2004

Neurofibrillary tangles in ALS and Parkinsonism-dementia complex focus in Kii, Japan.

Brains of 41 residents without neurodegenerative diseases in the high-incidence area of ALS/parkinsonism-dementia complex (ALS/PDC) of the Kii Peninsula of Japan were neuropathologically examined. Neurofibrillary tangles (NFTs) in the hippocampal area were present in 11 of the 41 cases, but the frequency of NFT-positive cases in each age group was similar to that of the normal Japanese population and far less than that of Guamanians without ALS/PDC.

Adolescent↗
PubMed2004

Direct measurement of human sympathetic nerve conduction velocity.

We evaluated a method for direct measurement of conduction velocity (CV) in sympathetic nerves in humans using a double-recording method of skin sympathetic nerve activity (SSNA) by microneurography. SSNA in the tibial nerve was recorded simultaneously at proximal and distal sites in the popliteal fossa (short-distance study) or at the popliteal fossa and ankle (long-distance study). In both studies, CVs were determined by dividing the interelectrode distance on the skin by the difference in conduction time between the rising-phases (rising-phase analysis) or peaks of the integrated bursts (peak-to-peak analysis). The measurement using long distance and peak-to-peak analysis had the highest accuracy; it is an orthodromic conduction measurement, is unrelated to eliciting stimulus, has high temporal resolution, and is not affected by the effector organ conditions. The average CV of resting SSNA was 0.93 +/- 0.09 m/s.

Action Potentials↗
PubMed2004

[Successful treatment by tacrolimus in two patients with Osserman's grade III intractable myasthenia gravis and elderly IIb].

Tacrolimus, a potent immunosuppressive agent, has recently become available for the treatment of myasthenia gravis (MG). However, few reports have evaluated the usefulness of tacrolimus in the elderly and in intractable MG classified as Osserman's grade IIb or higher. In this study, we examined the effects of tacrolimus in two patients with postthymectomy Osserman's grade III and IIb MG. The effects of tacrolimus were evaluated using the modified quantitative MG score (QMG score) and anti-acetylcholine receptor antibody (AChRAb) titer. Patient 1 was a 39-year-old woman with Osserman grade III MG. Her MG score improved after tacrolimus administration (3 mg/day), allowing gradual decreases in the doses of prednisolone and pyridostigmine because of improvement in MG symptoms. The AChRAb titer also decreased from 100.0 to 25.7 nmol/l during tacrolimus treatment. The concentrations of tacrolimus in whole blood ranged from 5.5 to 8.2 ng/ml during treatment. Patient 2 was a 68-year-old man diagnosed with Osserman grade IIb MG. After the initiation of tacrolimus treatment, dysphagia improved dramatically, and he was able to swallow food without a nasal feeding tube. The AChRAb titer decreased from 42.4 to 23.4 nmol/l during the treatment period. The concentration of tacrolimus in whole blood was 7.0 ng/ml 6 days after the initiation of treatment. These findings suggest that tacrolimus is effective in intractable and elderly MG patients.

Adult↗
PubMed2004

Steroid-induced diabetes mellitus and related risk factors in patients with neurologic diseases.

STUDY OBJECTIVE: To determine the frequency of steroid-induced diabetes mellitus (SDM) and the related risk factors in patients with neurologic diseases who receive high doses of steroids. DESIGN: Retrospective chart review. SETTING: Neurology ward of a university-affiliated hospital. PATIENTS: Twenty-five patients with neurologic diseases who received prednisolone 30-60 mg/day orally after breakfast for more than 2 weeks. MEASUREMENTS AND MAIN RESULTS: Plasma glucose concentrations were determined immediately before and 2 hours after each meal. Steroid-induced diabetes mellitus was diagnosed if the patient had either a fasting glucose concentration of 126 mg/dl or greater, or a random glucose concentration of 200 mg/dl or greater. The patients were divided into two groups on the basis of whether SDM had developed (13 patients) or not (12 patients). Ages, body mass indexes, cumulative total doses and daily doses of prednisolone, duration of therapy, and serum cholesterol and triglyceride concentrations were compared between the groups. Thirteen of the 25 patients were identified with SDM, and all of them had plasma glucose concentrations of 200 mg/dl or greater 2 hours after lunch. Mean age (59.1 +/- 10.2 yrs) and cholesterol concentration after prednisolone treatment (226.8 +/- 36.4 mg/dl) in the SDM group were significantly higher than those values in the non-SDM group (41.3 +/- 18.0 yrs and 188.1 +/- 27.2 mg/dl, respectively, p<0.01). CONCLUSIONS: A close relationship among postprandial hyperglycemia, advanced age, and hypercholesterolemia is a characteristic of SDM in patients with neurologic diseases. Therefore, monitoring the plasma glucose concentration 2 hours after lunch may be useful to detect SDM in these patients.

Adult↗