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T Hosono

Publications and source records attributed to T Hosono.

64 records · Page 4Linked to original sources
PubMed1985

Responses of thalamic and hypothalamic neurons to scrotal warming in rats: non-specific responses?

Activities of thalamic and hypothalamic neurons in response to scrotal temperature change were investigated in urethanized (1.2-1.5 g/kg) rats with special attention to changes in cortical electroencephalogram (EEG). Somatosensory relay neurons were identified electrophysiologically in the ventrobasal complex (VB) of the thalamus. These neurons had tactile receptive fields in areas outside the scrotum. Forty out of 44 of these neurons responded to scrotal warming by increase in firing rate. The responses occurred abruptly at threshold temperatures ranging from 31 to 40 degrees C (switching response) with simultaneous changes in EEG from high to low voltages (desynchronization). In both the thalamus and the hypothalamus, neurons excited or inhibited by scrotal warming were also excited or inhibited, respectively, by noxious stimulation that produced EEG desynchronization. Neurons showing no response to scrotal warming were not affected by noxious stimulation. In deeply anesthetized (2.5 g/kg urethane) rats, VB relay neurons responded to tactile stimulation of their receptive fields, but scrotal warming produced no change in either EEG or activities of thalamic and hypothalamic neurons. These facts suggest that the responses of thalamic and hypothalamic neurons to scrotal warming may be 'non-specific'. Most thalamic and hypothalamic neurons showing switching responses did not appear to mediate specific information concerning scrotal skin temperature.

Anesthesia, General↗
PubMed1984

Threshold temperatures of diencephalic neurons responding to scrotal warming.

Neurons in the rat's thalamus and hypothalamus abruptly change their firing rates from minimum to maximum, or vice versa, with increase in scrotal temperature of 1 degree C or less ("switching response"). The threshold temperature of the switching response was compared in pairs of neurons simultaneously recorded from the right and left thalamus or from the right thalamus and the left hypothalamus. In dynamic conditions in which scrotal skin was gradually warmed at rates of 1-7 degrees C/min, the threshold temperatures of each neuron pair differed by only 0.4 degree C or less. The threshold temperatures of static responses of each pair of neurons, which was determined with step changes in scrotal temperature, fell in a range less than 0.8 degree C. Scrotal warming produced desynchronization of cortical EEG which was monitored during unit recordings. The change in EEG occurred at about the same scrotal temperature at which the switching responses of the diencephalic neurons were elicited.

Animals↗
PubMed1980

Model of interaction of ajmaline with polyvinylpyrrolidone.

The chemical shifts in the Fourier transform 13C-NMR spectrum of ajmaline were assigned from consideration of the acetylation shifts and multiplet splitting in the off-resonance decoupled spectrum. On the basis of the assigned signals, the changes of chemical shifts in ajmaline induced by polyvinylpyrrolidone were investigated, and an interaction model of ajmaline with polyvinylpyrrolidone in chloroform was proposed.

Ajmaline↗
PubMed1975

Comparative studies of parasympatholytic drugs on stomach (double blind test) and analysis of relation between gastric form and tonus.

Effects of 3 kinds of parasympatholytic drugs (timepidiumbromide, hyoscine-N-butylbromide and prifinium-bromide) and placebo (physiological saline solution) on the gastrointestinal tract were evaluated roentgenographically by double blind technique in a total of 101 male human subjects. The results may briefly be summarized as follows: 1. There were significant differences on hypotonic rate being one of the indexes of the gastric tonus between timepidium-bromide and placebo. The effects of 3 experimental drugs were significantly high as compared with that of placebo on peristaltic movement of the stomach. The effect of timepidium-bromide was significantly different from that of placebo on the site of arrival of barium. 2. The comparison of degrees of the gastric tonus between main and control tests revealed that the effect of placebo obtained in the main test was significantly inferior to that of hyoscine-N-butylbromide obtained in the control test, whereas there existed no significant differences of the effects among 3 active drugs. 3. Effects of each drug on the gastric tonus which was scored by hypertonic, normotonic and hypotonic state were evaluated by stratification. The result showed that the effect of timepidium-bromide was significantly greater than that of placebo. 4. All active drugs were not significantly different in terms of 7 observed values each on the gastric form.

Adhesiveness↗
PubMedDate not supplied

A case of fetal complete heart block recorded by magnetocardiography, ultrasonography and direct fetal electrocardiography.

Fetal magnetocardiograms (FMCGs) were recorded in a case of fetal complete heart block (CHB) from the 30th to the 37th week of gestation using the multichannel SQUID system (Hitachi, Japan). M-mode ultrasonography and direct fetal electrocardiography using needle electrodes revealed fetal CHB. We identified independent fetal P-waves and QRS complexes in the FMCG recorded in the 32nd week of gestation when the fetal atriums were close to the FMCG sensor. We also recorded FMCG P-waves in the 37th week of gestation when the fetal heart was larger. Fetal heart position and size are important for obtaining a useful FMCG. To establish FMCG as a diagnostic tool of fetal arrhythmia, comparative studies with FECG are needed.

Adult↗
PubMedDate not supplied

A fetal Wolff-Parkinson-White syndrome diagnosed prenatally by magnetocardiography.

We report a case of fetal Wolff-Parkinson-White (WPW) syndrome diagnosed prenatally by magnetocardiography (MCG). At 32 weeks' gestation, the fetus was diagnosed to have a paroxysmal supraventricular tachycardia by ultrasonography and direct fetal electrocardiogram (ECG). Transplacental fetal therapy by maternal oral administration of propranolol resolved the fetal tachyarrhythmia. Although the wave forms of the fetal MCG at 32 weeks' gestation were normal, the fetal MCG at 35 weeks' gestation showed a short PR interval and a long QRS complex duration with a delta wave, indicating WPW syndrome. The findings of the fetal MCG were confirmed by the postnatal ECG. MCG made the prenatal diagnosis of WPW syndrome possible.

Adult↗