Biomedical subjects

Y Waseda

Publications and source records attributed to Y Waseda.

17 recordsLinked to original sources

PubMed2001

Effects of facial affect recognition on the auditory P300 in healthy subjects.

We examined the effects of facial affect recognition on auditory ERP using facial drawings depicting sadness, no emotion, pleasure and anger. Auditory ERP were recorded using an oddball paradigm in 13 women and 13 men while pictures and test tones were presented. P300 peak amplitude, area, and latency, and also subject's reaction time, were evaluated. The face showing pleasure resulted in the smallest P300 peak amplitude. Amplitudes were successively greater with anger, sadness, and no emotion. The P300 area showed facial affect effects resembling effects on peak amplitude. However, facial expression influenced P300 latency in different patterns suggesting the involvement of independent mechanisms. The reproducibility between sessions of the P300 measurements was tested. Both the P300 amplitude and area were largest when viewing neutral pictures, but smallest when viewing pleasant pictures in both sessions. While amplitude and the area of P300 were significantly larger in women than in men, gender was a less potent modifier of the influence of facial expression on P300 parameters. Reduced P300 amplitude and area apparently reflected an inhibitory effect of attention by emotion from facial expressions, especially for pleasure.

Adult↗

PubMed2001

Abnormal exploratory eye movements in schizophrenic patients vs healthy subjects.

OBJECTIVE: We examined previously described exploratory eye movements abnormalities as biologic markers in schizophrenic patients in comparison with age-matched healthy subjects. MATERIAL AND METHODS: Using an eye-mark recorder, eye movements were analysed for mean gazing time, total number of gazing points, mean eye scanning length, total eye scanning length, and total gazing times as subjects viewed six simple pictures in preparation for copying them. RESULTS: In-patients, and to a lesser extent, out-patients, with schizophrenia showed a longer gazing time, fewer gazing points, a shorter mean and total eye scanning length. and longer gazing time than healthy subjects. In schizophrenic patients. negative symptom scores were positively correlated with mean gazing time (r = 0.33), and negatively correlated with the total number of gazing points (r = -0.29) as well as, the mean (r = -0.40) and total scanning length (r = -0.46). CONCLUSION: Exploratory eye movements are a biologic marker useful for evaluation of schizophrenia.

Adult↗

PubMed2001

Changes in auditory P300 with clinical remission in schizophrenia: effects of facial-affect stimuli.

The auditory P300 is affected by arousal and emotion. We examined the effect of drawings expressing sadness or pleasure on auditory event-related potentials (ERP) during recovery from schizophrenia. Oddball-paradigm auditory ERP were recorded while presenting one of these drawings to nine patients with paranoid schizophrenia and seven patients with other types of schizophrenia during the acute stage and again during remission. P300 parameters (amplitude, area, and latency), reaction time, and symptom scores were evaluated. P300 amplitude and area were significantly greater in the recovery than in the acute phase. Increases were larger when viewing drawings that expressed sadness than when viewing drawings that expressed pleasure. In paranoid-type patients, P300 when viewing pleasurable drawings was similar to that when viewing sad drawings during the acute phase; in remission, P300 was significantly larger when viewing sad drawings than when viewing pleasurable drawings. In non-paranoid patients, P300 while viewing pleasurable drawings was significantly larger than that while viewing sad drawings during the acute phase; this difference disappeared during recovery. P300 latency and reaction time were not influenced by facial-affect stimuli or recovery. A significant negative correlation was noted between amplitude and negative symptom scores. P300 amplitude and area may be useful state markers during recovery in schizophrenic patients. Effects involving attention resources and emotional arousal are also involved.

Adolescent↗

PubMed2000

Anomalous X-ray scattering for determining the partial structural functions of binary liquids.

The availability of intense white X-rays from synchrotron radiation sources has greatly improved both acquisition and quality of anomalous X-ray scattering (AXS) measurements. A demonstration is given of the usefulness of the AXS method for determining three partial structural functions of liquid matter by some selected examples of molten salts such as CuBr and RbBr.

Journal Article↗

PubMed2000

Thermal remediation of PCDD/Fs contaminated soil by zone combustion process.

A new thermal process has been proposed for remediating soils contaminated by chlorinated organic compounds, e.g., PCDD/Fs and PCBs. This is to apply the "zone combustion process" which utilizes stable combustion of coke particles in the packed bed to soils with air flow across the bed. The usefulness and validity were obtained the results showing that more than 98.9% of PCDD/Fs in the soil was successfully removed in a laboratory-scale experiment. Some pretreatment of the soil sample, such as drying, pre-granulation and addition of limestone was found to make the removal efficiency better. Although, some fundamentals on the behavior of PCDD/Fs, e.g., decomposition/vaporization ratios and formation of other compounds cannot be certainly identified yet, the present results clearly show a way to remediate the contaminated soils and solid wastes.

Benzofurans↗

PubMed2000

Therapeutic progress of two sibling cases exhibiting sleep-wake rhythm disorder.

In this study, two females, siblings who exhibited a non-24 h sleep-wake rhythm (non-24 h) at home were observed. However, they showed a delayed sleep phase syndrome (DSPS) immediately after admission to Kurume University Hospital. Melatonin (3 mg) was commenced following chronotherapy and this improved their sleep-wake rhythm. Polysomnography (PSG) showed decreased sleep latency and increased sleep stage. In these cases, the involvement of environmental factors was strongly suggested for the sleep-wake rhythm abnormalities as well as familial factors.

Adolescent↗

PubMed2000

Papain-hydrolyzed pork meat reduces serum cholesterol level and premature atherosclerosis in dietary-induced hypercholesterolemic rabbits.

The effects of the low-molecular-weight fraction of papain-hydrolyzed pork meat (LMF) on the plasma cholesterol level and the generation of atherosclerosis were studied in rabbits fed a cholesterol-enriched diet. In LMF-fed rabbits, the plasma and liver cholesterol concentrations were both significantly lower (p<0.0 1) than in rabbits fed untreated pork meat (PM). Similarly, the cholesterol concentrations of the chylomicron and VLDL fractions were significantly lower in LMF-fed rabbits than in rabbits fed PM. Deposition of lipid in transverse sections of the aortic arch was significantly less in rabbits fed LMF than in those fed PM. Electron microscopic studies revealed preventive effects against premature atherosclerotic lesions in the aorta of rabbits fed LME These results indicate that LMF has a hypocholesterolemic action and preventive effects against premature atherosclerosis.

Animals↗

PubMed1999

Experimental neonatal respiratory failure induced by lysophosphatidylcholine: effect of surfactant treatment.

The purpose of this study was to characterize the toxic effects of lysophosphatidylcholine (lyso-PC) on neonatal lung function. Various doses of lyso-PC (from 0 to 40 mg/kg) were administered to near-term newborn rabbits. Lung-thorax compliance during mechanical ventilation was significantly decreased by doses >/=10 mg/kg, and static lung volumes during deflation were decreased by doses >/=20 mg/kg. Using the same experimental model, we investigated the effects of modified porcine surfactant (Curosurf, 200 mg/kg). Animals exposed to lyso-PC at birth and treated simultaneously with surfactant showed a satisfactory therapeutic response, whereas those treated after 30 min failed to respond. These animals also had a much larger leak of albumin into the air spaces and an elevated minimum surface tension of the lavage fluid in a pulsating bubble surfactometer, suggesting inactivation of the exogenous surfactant. Timing of surfactant administration may thus be essential for the therapeutic effect in this experimental model of acute lung injury.

Acute Disease↗

PubMed1998

Partial structural functions of binary liquids estimated from anomalous X-ray scattering measurements.

A new apparatus has been built for structural studies of high-temperature liquids using the anomalous X-ray scattering (AXS) method with synchrotron radiation. AXS measurements were made in the asymmetrical reflection mode for a free liquid surface by changing the beam direction using an additional mirror system. The usefulness and capabilities of this new equipment were confirmed by obtaining the individual partial structural functions of liquid Bi(30)Ga(70) alloy.

Journal Article↗

PubMed1996

Internal Structure Analysis of Monodispersed Pseudocubic Hematite Particles by Electron Microscopy.

Morphology and internal structure of monodispersed pseudocubic hematite (alpha-Fe(2)O(3)) particles produced by the gel-sol method were investigated in detail through high-resolution electron microscopy on their thin sections prepared with an ultramicrotome. It was confirmed that the c-axis of a particle corresponded to the longest diagonal axis of the particle. High-resolution electron micrographs of thin sections directly revealed the polycrystallinity of the particles and clearly showed the arrangement of the subcrystals and their crystallographic orientations. The subcrystals near the surface of a particle were of a rectangular shape bound by the $ \{01\overline{1}2\} $ planes, and their width was about 12-16 nm with small variation of the length depending on the position in a particle. The subcrystals were radially developed from the center of a particle in all directions, but most preferentially in the longest diagonal axis of a particle. Besides, it was found from EDX analysis that the adsorbed Cl(-) ions as a shape controller were incorporated into the pseudocubic hematite particles during their growth.

Journal Article↗

PubMed1996

Disparity between tidal and static volumes of immature lungs treated with reconstituted surfactants.

We biologically assessed functions of several reconstituted surfactants with the same minimum surface tension (2-3 mN/m) as "complete" porcine pulmonary surfactant (natural surfactant) but with longer surface adsorption times. Administration of natural surfactant (adsorption time 0.29 s) into the lungs of surfactant-deficient immature rabbits brought a tidal volume of 16.1 +/- 4.4 (SD) ml/kg during mechanical ventilation with 40 breaths/min and 20 cmH2O insufflation pressure. In static pressure-volume recordings, these animals showed a lung volume of 62.4 +/- 9.7 ml/kg at 30 cmH2O airway pressure and maintained 55% of this volume when the pressure decreased to 5 cmH2O. With two reconstituted surfactants consisting of synthetic lipids or isolated lipids from porcine lungs plus surfactant-associated hydrophobic proteins (adsorption times 0.57 and 0.78 s, respectively), tidal volumes were < 38% of that with natural surfactant (P < 0.05), but static pressure-volume recordings were not different. Care is therefore needed in estimating the in vivo function of surfactant preparations from minimum surface tension or static pressure-volume measurements.

Animals↗

PubMed1977