Biomedical subjects

Masaaki Kato

Publications and source records attributed to Masaaki Kato.

At least 19 recordsLinked to original sources

PubMed2006

Reduced frontal asymmetry of delta waves during all-night sleep in schizophrenia.

Delta wave deficits during sleep have been observed in patients with schizophrenia. Decreased slow-wave sleep is reported to be associated with negative symptoms. Frontal lobe dysfunction is also believed to underlie negative symptoms of schizophrenia. This study was designed to identify functional abnormalities in schizophrenia manifested on patients' electroencephalograms. Polysomnograph examinations were performed in 12 healthy male volunteers and 11 male outpatients with schizophrenia. We investigated the laterality of frontal cortical delta waves in patients with schizophrenia and in healthy control subjects. Laterality of frontal cortex delta wave counts during all-night sleep was investigated by computer analysis. Total delta wave counts were lower in patients with schizophrenia than in control subjects. Control subjects showed significantly higher delta wave counts in the right frontal cortex than in the left. This asymmetry was not observed in patients with schizophrenia. These findings suggest that reduced right frontal delta wave dominance is involved in the pathophysiology of schizophrenia.

Adolescent↗

PubMed2006

Factor structure of the Dimensional Assessment of Personality Pathology-Basic Questionnaire and its relationship with the revised NEO personality inventory in a Japanese sample.

The Dimensional Assessment of Personality Pathology, Basic Questionnaire (DAPP-BQ) was developed to assess 18 personality traits that provide a systematic representation of personality disorder. This study investigates the reliability and validity of the Japanese version of the DAPP-BQ and the relationship between the DAPP-BQ and Revised NEO Personality Inventory (NEO-PI-R) in a heterogeneous general population sample (n = 1485). Internal consistency (coefficient alpha) and test-retest reliability over a 3-week period was satisfactory for all scales. Factor analysis yielded 4 factors labeled "emotional dysregulation," "dissocial behavior," "inhibition," and "compulsivity" that accounted for 76.0% of the total variance. Subsequently, we investigated the relationships between the 18 dimensions and the 5 dimensions of the NEO-PI-R in a second heterogeneous general population sample (n = 717). Combined factor analysis of the 2 scales again yielded 4 factors accounting for 70.4% of the total variance. Finally, we used multiple regression analyses to examine the extent to which the 5 NEO-PI-R scales could be used to predict individual DAPP-BQ scales. These indicated that the NEO-PI-R does not have content that covers some DAPP-BQ dimensions, especially conduct problems, narcissism, and stimulus seeking.

Adult↗

PubMed2006

Alteration of familial ALS-linked mutant SOD1 solubility with disease progression: its modulation by the proteasome and Hsp70.

Accumulation of misfolded Cu/Zn superoxide dismutase (SOD1) occurs in patients with a subgroup of familial amyotrophic lateral sclerosis (fALS). To identify the conversion of SOD1 from a normally soluble form to insoluble aggregates, we investigated the change of SOD1 solubility with aging in fALS-linked H46R SOD1 transgenic mice. Mutant SOD1 specifically altered to insoluble forms, which were sequentially separated into Triton X-100-insoluble/sodium dodecyl sulfate (SDS)-soluble and SDS-insoluble/formic acid-soluble species. In spinal cords, the levels of SDS-dissociable soluble SOD1 monomers and SDS-stable soluble dimers were significantly elevated before motor dysfunction onset. In COS-7 cells expressing H46R SOD1, treatment with proteasome inhibitors recapitulated the alteration of SOD1 solubility in transgenic mice. In contrast, overexpression of Hsp70 reduced accumulation of mutant-specific insoluble SOD1. SDS-soluble low molecular weight species of H46R SOD1 may appear as early misfolded intermediates when their concentration exceeds the capacity of the proteasome and molecular chaperones.

Age Factors↗

PubMed2006

Active cerebral perfusion during carotid endarterectomy.

A patient with critical stenoses in the bilateral internal carotid arteries (ICA) required multivessel coronary revascularization. The diameter of the left ICA was far greater than the right, which strongly suggested that the cerebral circulation was highly dependent on the left. During left ICA endarterectomy, active cerebral perfusion of 300 mL x min(-1) at 23 degrees C using an extracorporeal circulation was employed through the ICA under repair. Subsequently, coronary bypass was performed on-pump with the heart beating. The postoperative course was very good.

Carotid Artery, Internal↗

PubMed2006

[Successful salvage of a patient with cardiac arrest caused by multiple pulmonary emboli and lung abscesses due to infective endocarditis of the tricuspid valve: a case report].

A 28-year-old female developed infective endocarditis in the tricuspid valve and multiple lung abscesses due to septic pulmonary emboli early after intensive therapy for ulcerative colitis. The pathogen was methicillin-resistant Staphylococcus aureus. Usual antibiotic agents and linezolid were administered. Three weeks later, she fell into cardiopulmonary arrest due to further pulmonary emboli and required mechanical circulatory assist. Fatal brain damage was suggested at first. Two days later, she fully regained consciousness and underwent tricuspid valve replacement using mechanical valve and extirpation of septic pulmonary embolus. Mechanical circulatory assist was discontinued on the next day. After strenuous administration of linezolid and other drugs for 9 weeks, she was discharged from hospital on foot. We believe that early surgical intervention should be considered in patients with infective endocarditis in the right heart and subsequent septic pulmonary emboli. Linezolid was very useful in this patient.

Acetamides↗

PubMed2006

[Epilepsy and pseudoseizures derived from their dissociation].

Many epileptic patients have pseudoseizures (psychogenic nonepileptic seizures mimicking epileptic seizures) derived from their dissociation (conversion) or other psychiatric symptoms. The pseudoseizure cast many problems on medical support for their management. In this article I reported the result of investigation of pseudoseizures in an epilepsy unit in department of psychiatry, National Center Hospital for Mental, Nervous, and Muscular Disorders, National Center of Neurology and Psychiatry. And I reffered to treatment and prognosis of pseudoseizures. The key points for psychiatrists in treating epileptic patients having pseudoseizures were; 1) not to hesitate to consult with specialists about diagnosis, 2) to distinguish a pseudoseizure from an epileptic seizure and to treat them separately, 3) not to treat seizure phenomena but patients by keeping reliable relationship with them.

Conversion Disorder↗

PubMed2006

[Total arch graft implantation with open stent-graft placement for aortic arch aneurysm or dissection].

We have developed and routinely performed the total arch graft implantation with open stent-graft placement for aortic arch aneurysm or dissection. This method is easy and respiratory-troubleless method, because of ascending and arch replacement with 4 branched graft and descending graft implantation with stent-graft from opened aortic arch. This method is useful for the patient with aortic arch diseases concomitant with coronary artery bypass candidate, respiratory dysfunction and aortic dissection.

Aortic Dissection↗

PubMed2005

Effect of benzodiazepine hypnotic triazolam on relationship of blood pressure and Paco2 to cerebral blood flow during human non-rapid eye movement sleep.

We sought to clarify the effect of short-acting benzodiazepine hypnotic on the relationship of arterial blood pressure and arterial partial pressure of carbon dioxide (Paco2) to regional cerebral blood flow (rCBF) during human non-rapid-eye-movement (non-REM) sleep. Nine young normal volunteers were treated in a randomized, crossover design with triazolam or placebo and underwent positron emission tomography at night. During wakefulness and stage 2 and slow wave (stages 3 and 4) sleep, we measured mean arterial blood pressure (MAP), Paco2, and absolute CBF. With triazolam compared to placebo, MAP reduced gradually. During stage 2 sleep, Paco2 increased and whole-brain mean CBF decreased. With triazolam, relative rCBF of the left orbital basal forebrain decreased more during stage 2 than slow wave sleep, whereas absolute CBF of the occipital cortex and cerebral white matter remained constant. During triazolam-induced stage 2 sleep, absolute CBF of the cerebral white matter correlated more strongly to both MAP and Paco2 than during placebo sleep and also correlated more strongly to both MAP and Paco2 than absolute CBF of the occipital cortex. In the frontal white matter, during triazolam-induced stage 2 sleep compared to wakefulness, absolute CBF was significantly better correlated to MAP, but not to Paco2. During triazolam-induced stage 2, the cerebral white matter may receive a modulated CBF regulation having the strengthened relationship of Paco2 to CBF and, more locally, the frontal white matter may depend precariously on CBF regulation.

Adult↗

PubMed2005

Successful bridge to resynchronization therapy with a left ventricular assist system in a patient with idiopathic dilated cardiomyopathy.

Implantation of a left ventricular assist system (LVAS) in patients with idiopathic dilated cardiomyopathy (DCM) may improve cardiac function and allow explantation of the device. Generally, an ejection fraction of more than 40% is considered necessary for successful weaning from an LVAS, but less than 10% of DCM patients with an LVAS can achieve such a significant recovery of cardiac function. Cardiac resynchronization therapy, or atrial-synchronized biventricular pacing, has been found to treat congestive heart failure and ventricular dyssynchrony effectively. Here we report on a patient with an LVAS, in whom enough functional recovery could be obtained with resynchronization therapy for the device to be explanted successfully. A 32-year-old man was implanted with a Toyobo-NCVC paracorporeal LVAS to treat his intractable heart failure caused by idiopathic dilated cardiomyopathy. While on the LVAS for 8 months, his cardiac function recovered to some extent. The ejection fraction of his left ventricle (LVEF) improved from 9% to 41%. He chose explantation of the device rather than heart transplantation. Because he occasionally showed a wide QRS pattern on his ECG, epicardial biventricular pacing leads as well as a biventricular pacemaker were implanted on LVAS explantation surgery. An echocardiogram 2 weeks after explantation showed a marked difference in his LVEF by switching his biventricular pacing on and off (40% with biventricular pacing on and 29% with it off). Biventricular pacing may help recovery of cardiac function in selected LVAS patients and contribute to the increase in bridge to recovery cases.

Adult↗

PubMed2005

Expression profiling with progression of dystrophic change in dysferlin-deficient mice (SJL).

The SJL mouse is a model for human dysferlinopathy (limb-girdle muscular dystrophy type 2B and Miyoshi myopathy). We used cDNA microarrays to compare the expression profiles of 10,012 genes in control and SJL quadriceps femoris muscles in order to find genes involved in the degeneration and regeneration process and in dysferlin's functional network. Many genes involved in the process of muscle regeneration are observed to be up-regulated in SJL mice, including cardiac ankyrin repeated protein (CARP), Neuraminidase 2, interleukin-6, insulin-like growth factor-2 and osteopontin. We found the upregulation of S100 calcium binding proteins, neural precursor cell expressed, developmentally down-regulated gene 4-like (NEDD4L) with C2 domain, and intracellular protein traffic associated proteins (Rab6 and Rab2). These proteins have the potential to interact with dysferlin. We must reveal some other molecules which may work with dysferlin in order to clarify the pathological network of dysferlinopathy. This process may lead to future improvements in the therapy for human dysferlinopathy.

Animals↗

PubMed2005

Influence of functional appliances on masticatory muscle activity.

The purpose of the present study was to investigate the influence of an activator appliance and a spring active appliance on masticatory muscle activity by means of electromyography (EMG). Twelve adult males with good general health were recruited as subjects. Three functional appliances were used in each subject for long-period EMG recording during daytime and sleep and short-time EMG recording during voluntary biting. Following findings were obtained. (1) The activity of all muscles was greater during biting than during daytime and sleep, (2) the muscle activities tended to increase in the digastric muscle and to decrease in the temporal muscle with activators under all conditions, and (3) the temporalis-masseter ratios became lower with the biting use of appliances. Therefore, this study suggests that functional appliances should be used during sleep and during the day in combination with voluntary biting to achieve adaptation and development of the masticatory muscles.

Adaptation, Physiological↗

PubMed2005

Hoarseness due to bilateral vocal cord paralysis as an initial manifestation of familial amyotrophic lateral sclerosis.

Bulbar palsy is unusual as an initial manifestation of amyotrophic lateral sclerosis (ALS), although common in the advanced stages. In terms of bulbar palsy as a presenting symptom, dysarthria and dysphagia are of common features. Hoarseness, however, is an initial symptom of ALS in only a small number of patients. We report a 43-year-old female with hoarseness due to bilateral vocal cord paralysis as the first manifestation of ALS. Gene analysis revealed a heterozygous missense mutation in the SOD1 gene, which resulted in an amino acid substitution of isoleucine 149 by threonine. Hoarseness can be the initial symptom of ALS. Therefore, in cases of bilateral vocal cord paralysis of unknown etiology, ALS should be taken into consideration.

Adult↗

PubMed2005

Intellectual disability and psychotic disorders of adult epilepsy.

PURPOSE: To investigate the prevalence, psychopathology, and cognitive functions associated with psychotic disorders among adult epilepsy patients with intellectual disability (ID) based on a multicenter study in Japan. METHODS: The study was divided into three phases: a prevalence study of psychotic disorders among new referrals of epilepsy, a polydiagnostic comparative study of patients with psychotic epilepsy and those with schizophrenia, and a neuropsychological study of patients with psychotic epilepsy and education level-matched controls. RESULTS: Among 336 new referrals of epilepsy, a higher prevalence of psychotic disorders was found among patients with ID (24%) than among those with normal intelligence (6%). The psychotic symptoms and operational diagnoses of psychotic epilepsy patients with ID were similar to those of patients with normal intelligence. A wide range (7-86%) of psychotic epilepsy patients was diagnosed as having schizophrenia, depending on the operational criteria used. Patients with psychotic epilepsy had more disturbances in verbal memory and attention functions than controls. CONCLUSIONS: Epilepsy patients with ID show a predisposition to develop psychotic disorders. Distinguishing their psychotic symptoms from those of schizophrenia is difficult. Subtle cognitive disturbances predispose to psychotic disorders in epilepsy.

Adult↗

PubMed2005

Intellectual prognosis of status epilepticus in adult epilepsy patients: analysis with Wechsler Adult Intelligence Scale-revised.

PURPOSE: Status epilepticus (SE) appears to cause cognitive dysfunction as well as other serious neurologic sequelae. To confirm whether SE produces a subsequent intellectual decline, we evaluated intellectual function prospectively in adult epilepsy patients with and without SE. METHODS: Of 1,685 patients with epilepsy who underwent comprehensive neuropsychological testing in two national hospitals in Japan, 15 patients experienced an episode of SE afterward and underwent the second neuropsychological examination after the SE episode. Forty clinically matched patients with epilepsy, but without an episode of SE since their initial neuropsychological examination, were also reevaluated. We compared IQs and subscores from the Wechsler Adult Intelligence Scale-Revised between the two groups by repeated measures analysis of variance. In the patients who experienced an SE episode, SE-related variables (i.e., age at the SE episode and type and duration of SE) and epilepsy-related variables such as epilepsy type, lateralization of EEG abnormalities, the presence of mesial temporal sclerosis, and previous history of SE, were evaluated in relation to intellectual outcome. RESULTS: Patients with SE, in comparison to those without SE, failed to show any significant post-SE intellectual decline. Furthermore, neither the SE-related variables nor the clinical characteristics were correlated with intellectual outcome. CONCLUSIONS: Our findings suggest that SE does not lead to a significant intellectual decline in adult patients receiving treatment for epilepsy.

Adult↗

PubMed2005

[Coronary artery bypass grafting in patients undergoing chronic hemodialysis: importance of wound healing and hypoproteinemia].

OBJECTIVES: Outcome of coronary artery bypass grafting (CABG) in patients undergoing chronic hemodialysis was studied. METHODS: Between January 1996 and August 2004, 49 consecutive hemodialysis patients [38 males and 11 females, mean age 60.0 years (range 47-74 years)] underwent CABG using cardiopulmonary bypass. Duration of hemodialysis was 5.2 years (range 1 month-21 years), and 32 patients were diabetics. Surgery was conducted on the emergency/urgency basis in 12 patients, and intraaortic balloon pumping was placed in 7. Left ventricular ejection fraction was 57.7 +/- 16.3% (range 27-84%). Nine patients underwent concomitant valve surgery. CABG was performed under hypothermic cardiopulmonary bypass and ventricular fibrillation except in one patient, and intraoperative hemodialysis was also performed. Continuous hemodiafiltration was used in the early period after surgery. RESULTS: Number of bypass grafts was 3.0 +/- 1.0 (range 1-6), and the unilateral internal thoracic artery was used in 29 patients. Operation time, cardiopulmonary bypass time, and aorta clamp time were 313 +/- 87, 145 +/- 63, and 49 +/- 43 min, respectively. Diffuse pericardial adhesion was present in five patients. Severely atheromatous ascending aorta precluded manipulation in seven patients. Although the 30-day mortality was 2.0% (one case), all in-hospital mortality over 9 months was 14.3% (seven cases). The morbid events were mediastinitis in seven cases, reexploration for hemorrhage in seven, pneumonia in two, abdominal complication in three, and stroke in one. Delayed onset mediastinitis was common. Risk factors for death were mediastinitis and serum albumin levels < 3.5 g/dl (both p < 0.05), both of which were wound healing-related factors. CONCLUSIONS: CABG in hemodialysis patients carries a high risk. Patients with hypoalbuminemia appear to require special consideration.

Aged↗

PubMed2005

[Active infective endocarditis remaining latent for six weeks after discontinuation of antibiotic therapy: a case report].

A 75-year-old man was treated for 4 weeks with penicillin administration for infective endocarditis in the mitral valve caused by Enterococcus faecalis. The infection recurred, so he received penicillin administration for a further 6 weeks. He remained afebrile and all laboratory examinations were within normal limits for 6 weeks after the antibiotic treatment was discontinued, but the vegetation remained large and highly mobile. Since the onset, possible embolic episodes had occurred three times. He underwent mitral valve repair with annuloplasty. Although the infection appeared to have healed by antibiotic therapy, resected tissue was strongly positive for Enterococcus faecalis. This case suggests that surgery should be aggressively considered if the vegetation does not shrink markedly.

Aged↗

PubMed2004

Cerebral white matter blood flow is constant during human non-rapid eye movement sleep: a positron emission tomographic study.

This study aimed to identify brain regions with the least decreased cerebral blood flow (CBF) and their relationship to physiological parameters during human non-rapid eye movement (NREM) sleep. Using [(15)O]H(2)O positron emission tomography, CBF was measured for nine normal young adults during nighttime. As NREM sleep progressed, mean arterial blood pressure and whole brain mean CBF decreased significantly; arterial partial pressure of CO(2) and, selectively, relative CBF of the cerebral white matter increased significantly. Absolute CBF remained constant in the cerebral white matter, registering 25.9 +/- 3.8 during wakefulness, 25.8 +/- 3.3 during light NREM sleep, and 26.9 +/- 3.0 (ml.100 g(-1).min(-1)) during deep NREM sleep (P = 0.592), and in the occipital cortex (P = 0.611). The regression slope of the absolute CBF significantly differed with respect to arterial partial pressure of CO(2) between the cerebral white matter (slope 0.054, R = - 0.04) and frontoparietal association cortex (slope - 0.776, R = - 0.31) (P = 0.005) or thalamus (slope - 1.933, R = - 0.47) (P = 0.004) and between the occipital cortex (slope 0.084, R = 0.06) and frontoparietal association cortex (P = 0.021) or thalamus (P < 0.001), and, with respect to mean arterial blood pressure, between the cerebral white matter (slope - 0.067, R = - 0.10) and thalamus (slope 0.637, R = 0.31) (P = 0.044). The cerebral white matter CBF keeps constant during NREM sleep as well as the occipital cortical CBF, and may be specifically regulated by both CO(2) vasoreactivity and pressure autoregulation.

Adult↗

PubMed2004

A polydiagnostic and dimensional comparison of epileptic psychoses and schizophrenia spectrum disorders.

After establishing the validity of the Japanese version of the Operational Criteria Checklist for Psychotic Illness (OPCRIT), we applied it to 58 consecutive patients with epileptic psychoses (index group) and to age- and sex-matched controls with schizophrenia spectrum disorders (control group). Compared with the control group, the index group had a low family history of schizophrenia, high premorbid personality disorder and unemployment, abrupt or acute onset of psychosis, good recovery with single or multiple episodes, and low deterioration from a premorbid level of function. From 9% to 52% of the index group and 38% to 84% of the control group were diagnosed with schizophrenia according to the operational criteria used. The percentages of patients diagnosed with schizophrenia based on various diagnostic criteria in the two groups were similar. In the index group, a diagnosis of schizophrenia was more commonly made among patients with inter-ictal psychosis than among those with post-ictal psychosis. An exploratory factor analysis identified five factor solutions of manic, negative, depressive, vegetative, and positive symptoms. Although positive and negative factor values were lower in the index group than in the control group, the two groups shared a similar factor profile. These results indicate that the difference in symptomatology between the two groups was quantitative rather than qualitative.

Adult↗