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Biomedical subjects

S Kuzuhara

Publications and source records attributed to S Kuzuhara.

At least 37 records · Page 2Linked to original sources

[A 59-year-old woman with recurrent convulsive seizures, cerebral infarctions, dementia, and intracranial calcifications].

A 59-year-old woman with recurrent seizures and progressive dementia is reported. Her past history and familial history were unremarkable. She became short-tempered at 56 years old (Oct. 1991). She had the first seizure attack and was admitted to a hospital at March 4, 1993, with prolonged disturbance of consciousness and subsequent mental deterioration. Her brain CT showed multiple small calcifications in the subcortical white matter and pons. The laboratory data including blood count, serum chemistry, serological studies and CSF was normal. MRI and digital subtraction angiography of the cranial vessels were unremarkable. There was a decrease in accumulation in the right cerebral hemisphere on 123I IMP SPECT. Despite anti-convulsant therapy, she had recurrent seizures several times, with gradual worsening of her mental state. She had the latest seizure attack and was transferred to Matsusaka Chuo Hospital, on August 29, 1993. After the attack she had been in the apallic state, and died on Nov. 13, 1995. This case was discussed in a neurological CPC. The discussants suggested that the isolated angiitis of the central nervous system caused secondary seizures and cerebral infarctions. Post-mortem examination revealed the CNS findings of vasculitis at various stages, calcification or mineralization mainly in the subcortical white matter and pons, massive cerebral infarctions with massive exudate, fresh and old small bleedings and exudate around the inflamed or calcified vessels. The white matter degeneration resembled that of Binswanger leukoencephalopathy. The final pathological diagnosis was isolated angiitis of the central nervous system since there was no inflammatory changes or atherosclerotic change of the blood vessels in the extracranial organs.

Calcinosis↗

[Essential points to differentiate various diseases causing parkinsonism].

This review article deals with the cardinal features to differentiate various conditions which present with parkinsonism, other than Parkinson's disease, Lewy body disease, progressive supranuclear palsy and corticobasal degeneration. Special attention is paid to the distinctive clinical features, laboratory data and neuroimaging findings of frequent diseases as well as important ones including multiple system atrophies(MSA), drug-induced parkinsonism, vascular pseudo-parkinsonism and manganese intoxication due to parenteral nutrition. MRI is useful to diagnose MSA, vascular pseudo-parkinsonism and manganese intoxication. Benzamide derivatives including sulpiride, tiapride, metoclopramide and cisapride are the main causes of drug-induced parkinsonism in recent years in Japan.

Diagnosis, Differential↗

[Encephalomyelopathy demonstrated on MRI in a case of chronic toluene intoxication].

Myelopathy in chronic toluene intoxication is rare. We present obvious lesions of the spinal cord on MRI in a 30-year-old Japanese man with chronic toluene intoxication. He had abused toluene for more than 10 years, and developed visual impairment, horizontal nystagmus, pyramidal tract signs, postural tremor, Romberg's sign, and sensory disturbance below the level of Th 2 dermatome. Anti-HTLV-1 antibody titer and vitamin B12 level in the serum were within normal limits. Biochemical analysis showed no increase of very long chain fatty acids. Cerebrospinal fluid showed no abnormal findings. Auditory brainstem response showed delay of I-V interpeak latency. Somatosensory evoked potential with the median nerve stimulation showed delay of N13-N20 central conduction time, which was later followed by absence of N14-N20 components. On MRI in T2 weighted image, marked high intensity was demonstrated in the posterior limbs of the internal capsule, and in the posterior columns and lateral tracts from the cervical through the upper thoracic cord. Cerebral lesions probably reflect demyelination and axonal degeneration produced by chronic toluene abuse. Spinal cord lesions seem to be secondary to nerve fiber changes more proximal to the nerve cell bodies.

Adult↗

[Changes of autonomic functions by endoscopic upper thoracic sympathectomy on idiopathic hyperhidrosis].

Changes of autonomic functions before and after bilateral endoscopic upper thoracic sympathectomy (EUTS) were evaluated in 13 patients with idiopathic hyperhidrosis, with the sympathetic skin response, coefficient of variation of R-R intervals, mean heart rate, thermography, and non-invasive Valsalva test of the tonometry method. EUTS electronically destructs the upper thoracic sympathetic ganglions which innervate the upper extremities, and partially the heart. The decrement of mean heart rate, and persistent inhibition of the vascular contraction and hidrosis of the hands appeared after EUTS. These manifestations were effect produced by the abortion of sympathetic activity by EUTS. In 10 of the 12 cases, the baroreceptor sensitivity index II of Valsalva test which reflects the sympathetic autonomic nervous function of the heart showed normal pattern after EUTS. Four cases revealed reincrement of both the blood pressure and heart rate at the latter half phase of the second stage of the Valsalva test. The sympathetic dysfunction of the heart was limited to the decrement of mean heart rate although EUTS partially destroys sympathetic fibers innervating the heart. A long-term study is necessary to evaluate the effect of EUTS on the cardiac function.

Adolescent↗

Accumulation of neurofilaments and SOD1-immunoreactive products in a patient with familial amyotrophic lateral sclerosis with I113T SOD1 mutation.

OBJECTIVE: To report neuropathologic features of argyrophilic inclusions in the anterior horn cells, motor cortex Betz cells, and neurons of the medullary reticular formation, spinal posterior horn, and Clarke column in a Japanese case of familial amyotrophic lateral sclerosis with I113T substitution in exon 4 of the copper-zinc superoxide dismutase (SOD1) gene. METHODS AND RESULTS: These inclusions were stained pale pink on the hematoxylin-eosin stain and dark on the Bielschowsky stain. They were positive for antibodies to phosphorylated neurofilaments, ubiquitin, and SOD1. On electron microscopy, they consisted of abundant intermediate filaments of 10 to 20 nm in diameter with disordered array indicating neurofilaments. CONCLUSION: These findings suggest that the I113T mutation induces accumulation of neurofilaments and SOD1 in the central nervous system neurons.

Aged↗

Creutzfeldt-Jakob disease with florid-type plaques after cadaveric dura mater grafting.

BACKGROUND: Many reported cases of iatrogenic Creutzfeldt-Jakob disease (CJD) developed after grafting cadaveric dura mater contaminated with CJD prions (dura-associated CJD). They are known to be clinicopathologically similar to sporadic CJD. We report herein 2 autopsy cases of dura-associated CJD with atypical clinicopathological features. PATIENTS: Two patients presented with progressive ataxia and mental deterioration 10 or 11 years after neurosurgical treatment with cadaveric dural grafting, which led to their deaths at 8 and 17 months, respectively, after onset. RESULTS: The cases were clinically atypical in exhibiting no or late occurrence of myoclonus and periodic synchronous discharges on electroencephalographic studies. They were pathologically unique in several aspects. The most striking feature was the presence of many prion protein (PrP) plaques in multiple areas in the brain. Some of them were the "florid" type surrounded by a zone of spongiform changes known to be a hallmark for the new variant CJD. The distribution of spongiform degeneration was also unique in that it was intense in the thalamus, basal ganglia, and the dentate nuclei of the cerebellum but milder in the cerebrum. There were no mutations in the PrP gene of the patients. There was no major difference in the size and glycoform pattern between the abnormal isoform of PrP extracted from the brain tissue from the dura-associated cases of CJD and that from a sporadic case of CJD. CONCLUSIONS: These 2 cases are clinicopathologically distinct from typical dura-associated cases of CJD. They may be a subtype with florid-type plaques in dura-associated CJD.

Aged↗

A novel mutation in the gene for the adult skeletal muscle sodium channel alpha-subunit (SCN4A) that causes paramyotonia congenita of von Eulenburg.

BACKGROUND: Paramyotonia congenita (PMC) of von Eulenburg is an autosomal dominant muscular disease characterized by exercise- and cold-induced myotonia and weakness. To date, 18 missense mutations in the adult skeletal muscle sodium channel alpha-subunit (SCN4A) gene have been identified to cause a spectrum of muscular diseases, including PMC of von Eulenburg, PMC without cold paralysis, potassium-aggravating myotonia, and hyperkalemic periodic paralysis. However, no obvious correlations can be made between the location or nature of amino acid substitutions in SCN4A and its clinical phenotypes. OBJECTIVE: To describe clinical and genetic features of a family with PMC of von Eulenburg. RESULTS: A Japanese family with cold-induced myotonia and weakness was diagnosed as having PMC of von Eulenburg. This phenotype was identified to be caused by a novel mutation that substituted a glutamic acid residue for a highly conserved glycine residue in the fourth transmembrane segment (S4) of domain IV. This predicted a decrease in positive charge specific for the S4. CONCLUSION: In addition to the G1456E identified in this study, 4 mutations that cause a decrease in positive charge in the S4/D4 are associated with the phenotype of PMC of von Eulenburg. This provides an important genotype-phenotype correlation in sodium channelopathies.

Adult↗

Novel chloride channel gene mutations in two unrelated Japanese families with Becker's autosomal recessive generalized myotonia.

We investigated the skeletal muscle voltage-gated chloride channel gene (CLCN1) in two unrelated Japanese patients with Becker's myotonia congenita. The non-myotonic parents of each patient were consanguineous. The proband of each family shares generalized myotonia, transient weakness after rest, and leg muscle hypertrophy. However, the disease severity related to the degree of myotonia differed, even in view of the response to long train nerve stimulation tests. CLCN1 gene analysis revealed a novel Ala659Val missense mutation identified to be homozygous in the more severe patient, while a novel Gln445Stop nonsense mutation was present in the other patient. Both mutations were absent in 90 Japanese normal controls. This is the first report of Japanese cases of Becker's myotonia congenita with CLCN1 gene mutations.

Adult↗

Input-output organization of the foot motor area in humans.

OBJECTIVE: A well-organized input-output relation similar to that of the monkey motor cortex has been demonstrated in the human hand motor area (Terao Y, Ugawa Y, Uesaka Y, Hanajima R, Gemba-Shimizu K, Ohki Y, Kanazawa I. Input-output organization in the hand area of the human motor cortex, Electroenceph clin Neurophysiol 1995;97:375-381). The aim of this study is to investigate the input-output organization of the human foot motor area. METHODS: We studied the effect of tactile stimuli given to the toe tip on the sizes of following responses; motor evoked potentials (MEPs) elicited by transcranial magnetic or electrical stimulation (TMS or TES) over the motor cortex and magnetic stimulation at the foramen magnum level. RESULTS: Air stimuli applied to the toe tip facilitated magnetically evoked MEPs of mainly the muscle attached to that toe, although a less prominent facilitation was also noted in muscles attached to the adjacent toes. Neither responses evoked by TES, nor those by stimulation at the foramen magnum level, were affected by air stimuli. These results suggest that the observed facilitatory effect occurs at the cortical level. CONCLUSION: A fairly well-organized input-output relation is present also in the foot motor area in humans, although the facilitatory effect is not so topographically restricted as is noted for the hand motor area.

Adult↗

Apolipoprotein E phenotypes in healthy normal controls and demented subjects with Alzheimer's disease and vascular dementia in Mie Prefecture of Japan.

In order to clarify the association between apolipoprotein E4 (ApoE4) and the pathogenesis of Alzheimer's disease (AD), we analyzed the distribution of the apolipoprotein E (ApoE) phenotypes and the frequency of the apo E alleles epsilon2, epsilon3, and epsilon4 in Japanese healthy controls (n = 1090, an average age of 51.2+/-12.6 years) and demented patients (n=103, mean age of 73.6+/-9.2 years). Demented subjects were divided into three subgroups: early-onset AD group (EOAD; n=25, mean age 63.0+/-6.2 years), late-onset AD group (LOAD; n=33, mean age 79.3+/-5.1 years), and vascular dementia group (VD; n=45, mean age 75.3+/-8.0 years). The apolipoprotein E phenotype was determined by isoelectric focusing and immunoblotting. There were no significant differences in the distribution of the apo E phenotypes by gender or age, and the estimated frequencies of epsilon2, epsilon3 and epsilon4 were 0.05, 0.86 and 0.09, respectively, in the normal controls. There was a significant difference in the distribution of the apo E phenotypes between LOAD and elderly controls aged more than 65 years (P<0.0001). The distribution of the apo E phenotypes in EOAD was the same as that in LOAD. The frequency of the epsilon4 allele was significantly higher in LOAD (0.35, P<0.0001) and EOAD (0.28, P<0.0001) than that in the control subjects (0.07), but not in VD (0.12, P=0.1630). The present findings suggest that ApoE4 is related with both EOAD and LOAD, but not with VD, and support the hypothesis that it is a genetic risk factor of AD.

Age of Onset↗

[Phase 1 clinical study of 123I-FP-CIT, a new radioligand for evaluating dopamine transporter with SPECT (I): Biodistribution and absorbed dose].

A Phase 1 clinical study of 123I-FP-CIT, N-(3-fluoropropyl)-2 beta-carbomethoxy-3 beta-(4-iodophenyl)nortropane (123I), developed for evaluation of dopamine transporter (DA-T) by single photon emission computed tomography (SPECT), was performed in 12 healthy male volunteers. No adverse reactions to 123I-FP-CIT (167 MBq) injection were observed. In sequential whole-body images after intravenous injection, the radioactivity was distributed mainly in the liver, abdomen, lungs and brain, and it decreased gradually with time. The radioactivity was excreted mainly in the urine and no prolonged retention of radioactivity was observed in any organs at 2 days post-injection. The radiation absorbed dose of 123I-FP-CIT, calculated on the basis of the pharmacokinetics, was equal to or less than those of other brain diagnostic imaging agents. These results suggest that i.v. injection of 123I-FP-CIT causes no significant problems in terms of its safety, biodistribution or absorbed dose.

Adult↗

[Phase 1 clinical study of 123I-FP-CIT, a new radioligand for evaluating dopamine transporter by SPECT (II): Tracer kinetics in the brain].

The kinetics of 123I-FP-CIT in the brain for healthy subjects were studied. Twelve dynamic SPECT data sets (0- to 6-hr after an intravenous injection) from a Phase 1 clinical trial of 123I-FP-CIT were analyzed. Tracer concentrations in the striatum, midbrain, cerebellum and cerebral cortex were measured on the SPECT images co-registered with the corresponding MR images. High tracer accumulation was observed in the striatum, which peaked at 60 min post-injection, followed by slow elimination (3%/hr). The kinetics were similar both in the cerebellum and in the cerebral cortex, which peaked at 15 min post-injection, followed by rapid elimination. Tracer accumulation in the midbrain was higher than in the cerebellum and cerebral cortex. The striatal specific/nonspecific binding ratio ((striatal-occipital)/occipital concentration ratio) was stable at 3-hr post-injection and later at a value of 3, suggesting that the specific binding of 123I-FP-CIT could be evaluated from a single SPECT image at 3- to 6-hr post-injection. The specific/nonspecific binding ratio at 4-hr post-injection showed a negative correlation with aging (r = -0.70, p = 0.01), with a decrease rate of 11%/decade (95% confidence interval: 3%-19%/decade).

Adult↗