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Biomedical subjects

K Nagamatsu

Publications and source records attributed to K Nagamatsu.

At least 19 recordsLinked to original sources

Intraoperative localisation of the lip sensory area by somatosensory evoked potentials.

Accurate localisation of the central sulcus enables maximum tumour resection with minimum morbidity in peri-Rolandic surgery. We investigated intraoperative somatosensory evoked potentials (SSEPs) with combined recording of lower lip and median nerve stimuli during craniotomy in nine patients with peri-Rolandic glioma. Using a custom clip electrode, the lip mucous membrane was stimulated with biphasic pulses with 0.2 ms duration, 10-14 mA intensity and a frequency of 0.7 Hz. Polarity inversion of the SSEP was detected across the central sulcus using median nerve and/or lower lip stimulation in eight of the nine patients in whom the tumour did not infiltrate the lip or hand sensory area. Recording of SSEPs with lower lip stimulation is useful if the resection margin is planned lateral to the hand representation area, if the hand representation area is not exposed by the craniotomy, or if the SSEPs for median nerve stimulation are not clear due to tumour infiltration.

Adult↗

Neuromagnetic separation of secondarily bilateral synchronized spike foci: report of three cases.

To demonstrate the high spatiotemporal resolution of magnetoencephalography (MEG), we report three cases with focal epilepsy that exhibited bilateral synchronized spikes on simultaneous scalp EEG and MEG recording. Constant time lags (19.4 +/- 3.0 ms and 20.0 +/- 5.5) between the leading and the following contralateral spikes were noted on MEG and the current dipole sources were localized in the bilateral homotopic regions symmetrically in Cases 1 and 3. In Case 2, MEG indicated leading spikes in the left frontal region, with a time lag of 42.3 +/- 8.4 ms to reach the contralateral frontal and bilateral temporal regions as well. Chronic subdural EEG recording in Cases 1 and 2 confirmed that the leading spike focus in MEG was close to the seizure onset zone in cortical EEG. Spatio-temporal analysis of MEG spikes may be useful to identify the primary epileptic region in patients with synchronized bilateral epileptiform discharges.

Adolescent↗

Neuromagnetic localization of N15, the initial cortical response to lip stimulus.

The initial cortical response of the trigeminal somatosensory evoked magnetic fields was measured for electrical stimulation of the lower lip in eleven subjects. The stimulus frequency was 0.7 Hz and stimulus intensity was nine times sensory threshold. The initial contralateral response was detected in 20 hemispheres at a latency of 14.6+/-1.3 ms and was named N15m. The equivalent current dipole of N15m was localized at the posterior bank of the central sulcus with anterior-superior orientation, and inferior to the dipole of N20m for median nerve stimulation.

Adult↗

Somatosensory evoked fields in comatose survivors after severe traumatic brain injury.

OBJECTIVE: To evaluate the cortical function quantitatively in patients in the chronic phase of severe traumatic brain injury. METHODS: Thirteen patients with severe traumatic brain injury due to traffic accident followed by persistent consciousness disturbance and disability were studied. Somatosensory evoked magnetic fields (SEFs) for unilateral median nerve stimulation were measured using a whole-head magnetoencephalography system. The latency and electrical current dipole (ECD) moment for the N20m, P30m, N45m and P60m components were calculated and compared with those of 14 age-matched healthy adults. RESULTS: The peak latency of N20m was longer (P<0.05) and those of P30m and N45m were shorter (P<0.01) in the patients than in normal adults. The ECD moment of N20m and P30m was smaller and that of N45m and P60m was larger in the patients than in normal adults (P<0.01). CONCLUSIONS: These results can be explained by the hypothesis that diffuse brain injury induces decreased and delayed input of the somatosensory afferent and compensational amplification of the response in the primary somatosensory cortex. Middle-latency SEFs may be applicable as a cortical functional measure for patients with severe traumatic brain injury.

Adult↗

[A case of motor neuron disease with presenile dementia showing bilateral degeneration of the pyramidal tract on cranial MRI].

A 58-year-old man developed dysarthria followed by a personality change. Subsequently, he developed muscle weakness and atrophy of the left upper and lower limbs, leading to repeated falls when he tried to walk. Neurological examination showed mild dementia, dysarthria, dysphagia, atrophy and fasciculation of the tongue, and muscle weakness and atrophy of all four extremities, particularly on the left side. Deep tendon reflexes were slightly diminished in the upper limbs and slightly exaggerated in the lower limbs without Babinski's sign. Cranial MRI revealed marked atrophy of the medial portions of the temporal lobes, more striking on the right, and T2-weighted imaging revealed symmetrical high-intensity signals from the posterior limbs of the internal capsules to the cerebral peduncles in the midbrain, extending to the pons on the left. 125I-IMP SPECT showed diffuse reduction of RI uptake in the frontal and temporal lobes, which was more marked on the right. We diagnosed this is a case of motor neuron disease with presenile dementia, which Mitsuyama et al. proposed as a new clinical entity, as well as a rare example of bilateral degeneration of the pyramidal tract on cranial MRI.

Alzheimer Disease↗

Remote discharges in the posterior language area during basal temporal stimulation.

A 23-year-old woman with refractory complex partial seizures underwent implantation of subdural grid electrodes over the left hemisphere to map epileptic foci and language function. Aphasic symptoms occurred during stimulation of the basal temporal area, which were always associated with intrastimulus remote discharges (ISRDs) in the classical posterior language area. No sequential language deficits occurred after anterior temporal lobectomy including the basal temporal area. These results suggest a close functional relationship between the basal temporal area and posterior language area in patients with temporal lobe epilepsy. ISRDs may explain the paradoxical observation that resection of the basal temporal language area results in no language deficits.

Adult↗

[A familial case of spinocerebellar ataxia type 8 (SCA 8)--its clinical findings and an issue about the genetic basis].

We report a 28-year-old woman with spinocerebellar ataxia type 8 (SCA 8). This patient began to exhibit dysarthria at the age of 19. At the age of 25, she fell and hit her head while drunk and then a neurosurgeon found that her cerebellum was atrophic on cranial CT and MRI. Neurological examination on admission to our hospital revealed ataxic speech, limb ataxia and mild hyperreflexia without Babinski's sign. Cranial MRI showed only mild atrophy of the cerebellar hemispheres and vermis. Based on the results of genetic analysis, which showed expanded CTG repeats[(CTA) 13 (CTG) 5 (CCG) 4 (CTG) 124] on the SCA 8 locus at 13q21, she was diagnosed as having SCA 8. As clinical signs of SCA 8, Koob et al. reported limb spasticity and diminished vibration perception including cerebellar ataxia. Furthermore, Hirose et al. and Satoh et al. reported cases showing involuntary movements such as myoclonus or chorea including cerebellar ataxia. Our case and Ikeda's cases presented a pure cerebellar phenotype. We think that SCA 8 exhibits clinical heterogeneity. On the other hand, Stevanin et al. and Worth et al. expressed doubt as to whether the SCA 8 locus at 13q21 is the gene actually responsible for autosomal dominant cerebellar ataxia (ADCA). We conclude that it is necessary to accumulate additional case reports, and to further investigate the relationship between the clinical findings and the results of genetic analysis in order to determine whether or not the SCA 8 locus at 13q21 is the genetic basis for ADCA.

Adult↗

Autosomal dominant familial spinal and bulbar muscular atrophy with gynecomastia.

The proband, a 53-year-old man, developed progressive spinal and bulbar muscular atrophy and gynecomastia at the age of 50. His father had weakness of lower limbs, and his son had a nasal voice, ocular movement abnormalities, and gynecomastia, whereas two of the proband's brothers showed either gynecomastia or tongue fasciculations. None of the patients showed any expansion of CAG repeat in the androgen receptor gene or any hormonal abnormality. Thus, this family is affected by a form of autosomal dominant spinal and bulbar muscular atrophy with gynecomastia.

Chromosome Aberrations↗

[A family with probable autosomal dominant bulbospinal muscular atrophy with gynecomastia].

We reported a 52-year-old man and his family with bulbospinal muscle atrophy (BSMA) and gynecomastia. The propositus presented with the clinical picture of late onset progressive bulbospinal muscular atrophy including postural tremor, general hyporeflexia, mild maturity onset diabetes, gynecomastia and sexual impotence. One of his brother and his two sons had gynecomastia. His elder son had ocular movement abnormality, associated movement of facial muscle and finger tremor. One of his brothers showed tongue fasciculation without gynecomastia. None of members examined had abnormal expansion of CAG repeats in the androgen receptor gene. We speculate that this family has a new clinical entity characterized by bulbospinal muscular atrophy with an autosomal dominant inheritance.

Aged↗

[Superselective angiographic findings of ipsilateral middle meningeal artery of chronic subdural hematoma in adults].

The authors reported the results of continuous superselective angiography of the ipsilateral middle meningeal artery (MMA) in cases of chronic subdural hematoma (CSH) in adults. MMA angiography was performed twice, at an interval of approximately two weeks, in 3 cases of conservative and 1 case of surgical treatment. The features of MMA angiographic findings were diffuse dilatation of MMA and visualization of scattered abnormal vascular networks (VN), which seemed to be macrocapillaries in the outer membrane of the CSH. In two out of the three cases of conservative treatment, these VN revealed a dynamic change temporarily and spatially, i.e. either enlargement or reduction. In one case with a long clinical course a stable MMA angiogram was seen. The operated case showed dramatic change on the second (postoperative) MMA angiogram. The VN around burr hole portion was huge and dark, and several newly visualized small arteries penetrated the enlarged VN, which was thought to have been caused by the operation. The mean blood pressure in the MMA was 103 mmHg. The reason for the acute enlargement of the CSH might be explained as arterial bleeding into the hematoma cavity, caused by rupture of thin walled macrocapillaries by direct arterial pressure.

Aged↗

[A case of thoracic extradural spinal cord teratoma with neurological sequelae more than 10 years after surgery].

We describe a rare case of a 42-year-old man with extradural spinal cord teratoma who presented with left Brown-Séquard syndrome more than 10 years after surgery for a left posterior mediastinal tumor. When he was 29 years old, he underwent an operation for a posterior mediastinal tumor. Histological findings showed adenocarcinoma in teratoma. Ten years after the operation, the patient developed left leg weakness. Three years later, he developed superficial sensory disturbance in his right leg. MRI showed extradural tumor formation at the level of the Th 9 vertebra, which compressed the spinal cord from the left posterior side. At surgery, the tumor was well encapsulated and extended to the left posterior side of the spinal cord through the intervertebral foramen. The histological findings were almost identical to those from the mediastinal tumor. This dumbbell tumor apparently developed from the remainder of the posterior mediastinal tumor over a period of more than 10 years.

Adenocarcinoma↗

Varicella pneumonia in a healthy adult presenting with severe respiratory failure.

We describe a case of varicella pneumonia in a 24-year-old healthy man presenting with severe respiratory failure. A chest radiograph showed diffuse, bilateral airspace consolidation; additional complications included liver dysfunction and thrombocytopenia. However, treatment with intravenous acyclovir and gamma-globulin improved his clinical symptoms and signs. A greater than four-fold change in paired titers of the varicella-zoster virus antibody was observed. Bronchoalveolar lavage performed during the recovery phase revealed increased total cell and lymphocyte counts and a decreased CD4:CD8 ratio of T lymphocytes. Transbronchial lung biopsy findings were compatible with a diagnosis of interstitial pneumonia.

Acyclovir↗

[A case of Kennedy-Alter-Sung (KAS) syndrome presenting as hypersexuality and elevated serum CK: usefulness of genetic analysis].

We report a unique case of KAS syndrome presenting as hypersexuality and elevated serum creatine kinase (CK). None of the other members of the patient's family had KAS. The patient had engaged in sexual behavior 4 approximately 5 times a week since his marriage. He did not have gynecomastia or hepatomegaly. Neurological examination revealed facial twitching and tongue atrophy and fasciculations. Mild to moderate muscular atrophy and weakness were evident in the proximal portion of the upper and the distal portion of the lower extremities. Deep tendon reflexes were absent, as were sensory disturbance and sphincter dysfunction. Laboratory data showed mild elevation of transaminase (GOT 113 U/L, GPT 69 U/L) and extreme elevation of CK (4,600 U/L) in serum. Electromyography and muscle biopsy from the left biceps showed chronic neurogenic atrophy. Genetic analysis showed increased expansion of a CAG repeat (44 repeats) in exon 1 of the androgen receptor gene. We diagnosed KAS syndrome based on the genetic analysis. This case is important in illustrating the clinical varieties of KAS syndrome, as well as the importance of genetic analysis in KAS syndrome cases presenting with atypical manifestations and without a family history.

Creatine Kinase↗

Accentuation by pertussis toxin of the 5-hydroxytryptamine-induced potentiation of ATP-evoked responses in rat pheochromocytoma cells.

We previously demonstrated that 5-hydroxytryptamine (5-HT) enhances the cationic current activated by extracellular ATP in rat pheochromocytoma PC12 cells. We report here that pertussis toxin (PTX) modulates this 5-HT-dependent enhancement in these cells. 5-HT potentiated ATP-evoked intracellular Ca2+ concentration ([Ca]i) rise and dopamine release over a concentration range from 1 to 100 microM. When cells were pre-treated with PTX, this potentiation was accentuated. Pretreatment with PTX also accentuated the 5-HT-dependent enhancement of the ATP-activated current. These results suggest that the enhancement by 5-HT of the ATP-evoked responses is negatively regulated by a mechanism mediated through PTX-sensitive GTP-binding protein.

Adenosine Triphosphate↗

Immunological abnormality in patients with lysinuric protein intolerance.

Lysinuric protein intolerance (LPI) is a rare hereditary disorder manifesting hyperammonemia induced by low levels of basic amino acids, these low levels being due to the impaired transport of these acids in the intestinal mucosa and the renal tubules. Low serum arginine levels and probably the consequently low in vivo levels of nitric oxide (NO), which against acts as a physiological and immunological mediator/modulator, are thought to influence the immunological status in patients with LPI. Accordingly, this study was conducted to. We found that patients with LPI had leukocytopenia, high serum IgG levels, a high ratio of CD44B4-positive lymphocytes (helper inducer) to CD42H4-positive lymphocytes (suppressor inducer), low levels of leukocyte phagocytic, cytotoxic, and natural killer cell activity, and increased spontaneous proliferation of lymphocytes. These results were probably the consequence of persistent low NO levels in vivo.

Adult↗