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Kiyoharu Inoue

Publications and source records attributed to Kiyoharu Inoue.

35 records · Page 2Linked to original sources
PubMed2004

Cognitive processes in two-point discrimination: an ERP study.

OBJECTIVE: To elucidate the temporal features of the cognitive process in two-point discrimination (TPD). METHODS: We measured somatosensory event-related potentials (ERPs) in 9 subjects during the TPD task, in which we provided a pair of electrical pulses simultaneously, altering the distance between the electrodes. We analyzed the TPD-related ERPs and investigated the relationship between the potentials and the subjects' judgments. RESULTS: During the TPD task, a negative potential approximately 140 ms after the stimulation (N140) was enhanced as compared to a stimulus counting task. Two late positive components, LPC-1 and LPC-2, whose peak latencies were 300 and 500 ms, respectively, were identified only in the TPD task. The LPC-1 was recorded dominantly in the fronto-central area, while the LPC-2 was detected dominantly in the centro-parietal area. The amplitude of the LPC-2 was significantly modulated by the degree of consistency in the subjects' judgment. On the other hand, these ERP components did not show significant difference between the alternate judgments, i.e. 'one-point' or 'two-point' judgment. CONCLUSIONS: Our results suggest that the N140 is related to the attention toward the stimulation. The LPC-1 and LPC-2 are likely to correspond to the processes represented by P3a and P3b, based on their temporal and spatial behavior.

Adult↗
PubMed2004

Effects of 1-Hz repetitive transcranial magnetic stimulation on acute pain induced by capsaicin.

The aim of this study is to investigate the efficacy of 1-Hz repetitive transcranial magnetic stimulation (rTMS) over the primary motor cortex (M1) on acute pain induced by intradermal capsaicin injection and to elucidate its mechanisms by single-photon emission computed tomography (SPECT). We compared time courses of a subjective scale of pain induced by intradermal capsaicin injection in seven normal subjects under three different conditions: rTMS over M1, sham stimulation, and control condition (natural course of acute pain without any stimulation). In ten normal subjects, using SPECT, we also studied differences in regional cerebral blood flow (rCBF) after capsaicin injection between two conditions: rTMS over M1 and the control condition. rTMS over M1 induced earlier recovery from acute pain compared with the sham or control conditions. Under rTMS over the right M1 condition compared with the control condition, the SPECT study demonstrated a significant relative rCBF decrease in the right medial prefrontal cortex (MPFC) corresponding to Brodmann area (BA) 9, and a significant increase in the caudal part of the right anterior cingulate cortex (ACC) corresponding to BA24 and the left premotor area (BA6). A region-of-interest analysis showed significant correlation between pain reduction and rCBF changes in both BA9 and BA24. We conclude that rTMS over M1 should have beneficial effects on acute pain, and its effects must be caused by functional changes of MPFC and caudal ACC.

Adult↗
PubMed2004

[Changes in visual event-related potentials and SPECT in dissociative amnesia].

A 29-year-old man was admitted because of sudden onset of retrograde amnesia. The patient was unable to recall events having occurred during the past 2 years. The impairment was especially serious with regard to personal memories during the 5 months prior to admission, while he had first been working as a full-time employee under stressful circumstance. A diagnosis of dissociative amnesia was made on the basis of absence of any systemic or neurological diseases that could cause amnesia, the inadaptable character of the patient, the nature of amnesia, and presence of stressful condition possibly related to the amnesia. Visual event-related potential (ERP) studies recorded with human face discrimination tasks demonstrated a P3a wave in response to a face of his superior in the office, whom he said that he had never seen before. The similar P3a wave was observed in response to a face quite familiar to the patient, his mother, but not to a face "truly" unknown to him. These findings suggest that the visual memory of his superior's face exists in the brain, but the patient is unable to retrieve it by some psychogenic mechanism. 131I-IMP SPECT revealed decreased perfusion in the left medial temporal lobe and the basal forebrain, suggesting the association between dissociative amnesia and focal brain dysfunction. While dissociative amnesia has been understood as psychogenic nature, both ERPs and SPECT are quite important tools to understand the association between the psychological phenomenon and biological changes of the brain in this disorder.

Adult↗
PubMed2004

[A case of heparin-induced thrombocytopenia that worsened preexisting cerebral infarction].

A 75-year-old man was admitted to our hospital with dysesthesia of the right lip, dysphagia and gait disturbance. He presented with right Wallenberg syndrome and brain MR image showed a fresh infarction in the right lateral medulla. Therapy with heparin and ozagrel sodium was started. For a time his symptom improved a little, but after 8 days he developed re-infarction, thrombocytopenia and DIC, while being treated with heparin for cerebral infarction. Heparin was discontinued, and these symptoms improved quickly. The clinical course and the positive anti-platelet factor 4-heparin complex antibody suggested that these symptoms were caused by heparin-induced thrombocytopenia (HIT). HIT should be included as a differential diagnosis for progression of ischemic stroke under heparin therapy.

Aged↗
PubMed2004

[A case of cardiac myxoma presenting with multiple cerebellar hemorrhages and elevation of interleukin-6 in the cerebrospinal fluid].

We report a 25-year old man with cardiac myxoma presenting with multiple cerebellar hemorrhages and elevation of interleukin-6 (IL-6) in the cerebrospinal fluid (CSF). The patient was first admitted to our hospital because of cerebral infarctions at the age of 23. After systemic exploration he was diagnosed as cardiac myxoma. In this patient, the serum level of IL-6 was elevated. The cardiac myxoma was resected and the serum IL-6 level returned to normal. His neurological symptoms improved almost to normal and he was discharged. The patient had been well for two years until he developed headache at the age of 25. Brain MRI revealed multiple cerebellar hemorrhages that overlaid old infarctions. The hemorrhages enlarged in a three months period and his headache became worse, and then he was admitted again. The IL-6 value was normal in serum at that time, but it was elevated in the CSF. The CSF IgG index was also elevated. Cerebral angiograms showed no abnormal vessel in the infratentorium, while multiple fusiform aneurysms were found in both middle cerebral arteries. A transesophageal echocardiography revealed no recurrence of cardiac myxoma. Craniotomy was performed and intracerebellar hematomas were removed. Histopathological examination showed only old and recent bleedings; no metastatic myxoma tissue was found. Although no myxoma tissue was found in biopsy specimen, it seemed reasonable that an elevated level of IL-6 in the CSF was due to metastasized intracranial myxoma, which caused cerebellar embolism, and then invaded the vessel walls and continued to grow. In reviewing the literature we have found no reported case of cardiac myxoma with analysis of IL-6 value in the CSF. We speculate that the level of IL-6 in the CSF might be a good marker for the neurological manifestations of cardiac myxoma.

Adult↗
PubMed2003

Adenoviral gene transfer of GDNF, BDNF and TGF beta 2, but not CNTF, cardiotrophin-1 or IGF1, protects injured adult motoneurons after facial nerve avulsion.

We examined neuroprotective effects of recombinant adenoviral vectors encoding glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), cardiotrophin-1 (CT1), insulin-like growth factor-1 (IGF1), and transforming growth factor-beta2 (TGFbeta2) on lesioned adult rat facial motoneurons. The right facial nerves of adult Fischer 344 male rats were avulsed and removed from the stylomastoid foramen, and adenoviral vectors were injected into the facial canal. Animals avulsed and treated with adenovirus encoding GDNF, BDNF, CNTF, CT1, IGF1 and TGFbeta2 showed intense immunolabeling for these factors in lesioned facial motoneurons, respectively, indicating adenoviral induction of the neurotrophic factors in these neurons. The treatment with adenovirus encoding GDNF, BDNF, or TGFbeta2 after avulsion significantly prevented the loss of lesioned facial motoneurons, improved choline acetyltransferase immunoreactivity and prevented the induction of nitric oxide synthase activity in these neurons. The treatment with adenovirus encoding CNTF, CT1 or IGF1, however, failed to protect these neurons after avulsion. These results indicate that the gene transfer of GDNF and BDNF and TGFbeta2 but not CNTF, CT1 or IGF1 may prevent the degeneration of motoneurons in adult humans with motoneuron injury and motor neuron diseases.

Adenoviridae↗
PubMed2003

Characterization of Danon disease in a male patient and his affected mother.

Danon disease, primary lysosome-associated membrane protein-2 (LAMP-2) deficiency, is histologically characterized by unusual vacuoles bound by membranes with sarcolemmal features in skeletal muscle. We studied skeletal muscle specimens from a male patient with genetically confirmed Danon disease who had two muscle biopsies, at age 20 months and 16 years, and from his mother with cardiomyopathy but without clinically apparent skeletal myopathy. In the patient, the number of vacuoles increased over the 14-year interval between biopsies, suggesting that the number of vacuolated fibers increases with age, and correlates with the development of muscle symptoms. In contrast, in the muscle biopsy from the mother there were no vacuoles even though she had decreased LAMP-2.

Adolescent↗
PubMed2003

Evaluation of baroreflex sensitivity by the sequence method using blood pressure oscillations and R-R interval changes during deep respiration.

BACKGROUND: Baroreflex sensitivity assessments have been considered to be important to evaluate cardiac autonomic neuropathy. The phenylephrine method, Valsalva maneuver or sequence method at rest caused several problems. We evaluated the usefulness of the sequence method during deep respiration. METHOD: Baroreflex sensitivity was evaluated in 20 normal volunteers and 50 patients with Parkinson's disease. R-R intervals and systolic blood pressures were obtained by electrocardiogram and tonometry using a continuous blood pressure monitoring system. The sequence method is an evaluation of baroreflex sensitivity using sequences of 3 or more consecutive beats for 4 min. Baroreflex sensitivity was also assessed by the Valsalva maneuver at 5 beats before the peak systolic blood pressure of phase IV. The slope of the linear interrelationship between systolic blood pressure and the following R-R interval, i.e. baroreflex sensitivity (ms/mm Hg), was calculated with a correlation coefficient greater than 0.8. RESULT: The mean value of baroreflex sensitivity obtained by the Valsalva maneuver was 7.91 in normal volunteers and 5.35 in patients with Parkinson's disease; the one obtained by the sequence method at rest was 9.10 in normal volunteers and 8.42 in patients with Parkinson's disease, and the one obtained by the sequence method during deep respiration was 10.23 in normal volunteers and 6.73 in patients with Parkinson's disease. In some cases with Parkinson's disease, baroreflex sensitivities could not be found, whereas in all patients with Parkinson's disease, the sequence method during deep respiration could be used for evaluations. Significant correlations were found among the baroreflex sensitivities obtained by the Valsalva maneuver, and the sequence method at rest or during deep respiration in normal volunteers and patients with Parkinson's disease. CONCLUSIONS: The baroreflex sensitivity obtained by the sequence method during deep respiration could be investigated noninvasively in all cases with PD, being thus a useful method for clinical evaluation of baroreflex sensitivity.

Aged↗
PubMed2003

The beneficial effect of donepezil on visual hallucinations in three patients with Parkinson's disease.

Visual hallucinations (VHs) are common psychiatric symptoms in patients with long-standing Parkinson's disease (PD). Treatment with neuroleptics or withdrawal of anti-PD drugs may improve VHs but will worsen motor dysfunctions. The authors report on 3 patients with long-standing PD who were treated with the cholinesterase inhibitor donepezil for the treatment of VHs. Each received a daily dose of 5 mg of donepezil, after reducing or discontinuing anti-PD medications had failed to relieve the VHs. In 2 patients (patient 1, 2), donepezil decreased VHs without worsening motor dysfunctions. In addition, the cognitive status of patient 2 improved. In patient 3, donepezil also resolved VHs, but delusions developed during treatment. After discontinuing donepezil, delusions disappeared and VHs reappeared. Donepezil may ameliorate visual hallucinations in PD patients, but controlled, double-blind trials are necessary to further clarify the effect of this drug on VHs in PD.

Aged↗
PubMed2003

[Sudomotor dysfunction in Parkinson's disease].

Autonomic dysfunction is often associated with the progression of Parkinson's disease (PD). The most frequent manifestations of autonomic dysfunction are cardiovascular symptoms, bladder and bowel dysfunction, and sudomotor dysfunction. However, sudomotor dysfunction in PD remains poorly understood. To evaluate sudomotor function in PD, we quantitatively measured sweating during untreated conditions in 20 patients with PD (age, 62 +/- 5 years) and in 10 age-matched control subjects (60 +/- 6 years). An evaporimeter can measure small amounts of water (g/m2h) evaporated from the body. This device was used to quantify sweating at different sites of the skin (forehead, arm, dorsal part of hand, chest wall, femur, and dorsal part of foot). Sweating demonstrated as amount of evaporated water (mean +/- SD g/m2h) was less in the patients with PD than in the control participants on the dorsal parts of the hand (13.7 +/- 5.2 vs. 23.9 +/- 5.5, p < 0.001) and foot (16.0 +/- 6.0 vs. 22.1 +/- 8.3, p < 0.05). On the dorsal part of the hand, sweating in the patients with PD at Yahr stages I and II was less than that in the control-Participants (15.2 +/- 6.3 vs. 23.9 +/- 5.5, p < 0.05). Sweating in the patients with PD at Yahr stages III and IV was less than that in the control participants on the dorsal parts of the hand (10.8 +/- vs. 2.7 vs. 23.9 +/- 5.5, p < 0.001), and foot (10.9 +/- 2.3 vs. 22.1 +/- 8.3, p < 0.005). Sweating on the dorsal part of the foot was less in the patients with PD at Yahr stages III and IV than that in those at Yahr stages I and II (10.9 +/- 2.3 vs. 18.4 +/- 6.1, p < 0.05). Sweating on the forehead in the patients with PD at Yahr stages I and II stage was slightly but not significantly less than that in the control participants (21.8 +/- 3.8 vs. 32.7 +/- 11.9, p < 0.2). Sweating on the forehead in the patients with PD at Yahr stages III and IV was sightly but not significantly greater than that in those at Yahr stages I and II (25.4 +/- 5.6 vs. 21.8 +/- 3.8, p < 0.2). Increased sweating on the forehead skin might compensate for decreased sweating on the extremital skin. Our results suggest that sudomotor dysfunction in PD primarily affects the distal parts of the upper and lower extremities. Sudomotor dysfunction affecting distal parts of the extremities worsens with increased severity of PD.

Aged↗
PubMed2003

[Cardiac sympathetic dysfunction in Parkinson's disease--relationship between results of 123I-MIBG scintigraphy and autonomic nervous function evaluated by the Valsalva maneuver].

We examined whether the results of 123I-MIBG scintigraphy reflect cardiac sympathetic nerve function in patients with Parkinson's disease (PD). The subjects were 62 patients with Parkinson's disease (age, 65.4 +/- 6.3 years) and 53 controls (65.2 +/- 7.1 years). All subjects underwent 123I-MIBG scintigraphy and QTc interval measurement on ECG. Hemodynamic autonomic function was estimated by the Valsalva maneuver in 37 subjects (63.9 +/- 5.2 years) randomly selected from the patients with PD. As control, the Valsalva maneuver was also done in 20 randomly selected controls (64.1 +/- 5.0 years), and 123I-MIBG scintigraphy was performed in 21 controls (67.7 +/- 5.3 years old). The subjects rested in a supine position for 20 min and were given an intravenous injection of 111 MBq 123I-MIBG. Relative organ uptake was determined by the region of interest (ROI) in the anterior view and the ratio of average pixel count in the heart (H) to that in the mediastinum (M) was calculated (H/M ratio) for early (after 15 min) and delayed (after 3 hrs) periods. The Valsalva maneuver was done by having the subjects exhale into a mouthpiece at an expiratory pressure of 40 mmHg for 15 seconds. Blood pressure and RR intervals were measured during the Valsalva maneuver by tonometry, using a noninvasive blood pressure monitoring system (ANS 508, Nihon Colin Co., Ltd.). Baroreceptor reflex sensitivities (BRS) of the second phase (BRS II) and fourth phase (BRS IV) of the Valsalva maneuver were calculated, and blood pressure elevations during the late second phase (IIp) and fourth phase (IVp) were measured. QTc was greater in the patients with PD (417 ms) than in the control subjects (409 ms). The H/M ratios of the early and delayed images in the patients with PD (1.76, 1.61) were significantly lower than those in the control subjects (2.56, 2.45). The early and delayed H/M ratios significantly correlated with the severity of disease according to Hoehn-Yahr stage. QTc interval and IVp significantly correlated with early and delayed H/M ratios. No other significant correlations were detected. The early H/M ratio in the patients with PD who had IVp within the normal range was lower than the early H/M ratio in control subjects. Our results show that early and delayed H/M ratio correlates with cardiac autonomic function, evaluated on the basis of QTc interval and the Valsalva maneuver, but not with baroreceptor reflex sensitivity or vasomotor autonomic function. Our findings suggest that silent cardiac autonomic dysfunction may be evaluated by 123I-MIBG scintigraphy, because early and delayed H/M ratios were lower in the patients with PD who had normal IVp than in the control subjects.

3-Iodobenzylguanidine↗