PubMed Health⌕ Search

Biomedical subjects

T Maeyama

Publications and source records attributed to T Maeyama.

At least 55 records · Page 3Linked to original sources
PubMed1988

Laryngeal reflex mechanism during deglutition--observation of subglottal pressure and afferent discharge.

In this investigation, particular attention was paid to elucidate the laryngeal reflex mechanism of protective closure and the sensory function of the larynx during deglutition. For this purpose, three different experimental procedures were adopted: (1) subglottal pressure of felines was measured during deglutition using a pressure transducer; (2) subglottal pressure of human beings was measured during deglutition using a pressure transducer; and (3) afferent discharges from superior and recurrent laryngeal nerves of felines were recorded. The following conclusions appear justified. (1) Feline and human subglottal pressure during deglutition showed the following pattern. The pressure rises with onset of deglutition, temporarily drops during laryngeal elevation, rises again during the downward movement of the larynx, and drops again at the end of the glutition. This pattern was not affected by the resection of the unilateral recurrent laryngeal nerve. (2) The superior laryngeal nerve is involved in the sensory function of the pharynx, larynx, and trachea. At least two types of afferent discharges from superficial and internal sensory nerves are suspected. Afferent discharges from the recurrent laryngeal nerves in the larynx and trachea are not as distinct as those of the superior laryngeal nerve, and this seems to correspond with various changes in the thorax. During deglutition, afferent discharges were recorded from superior to recurrent laryngeal nerves.

Animals↗
PubMed1988

A new gustometer for computer evaluation of taste responses in men and animals.

Many previous attempts to acquire gustatory evoked potentials (GEPs) in both men and animals could not satisfy strict requirements on purely unimodal stimulation free of contaminating artifacts. Therefore we developed an advanced new gustometer, based on our previous experience on olfactory evoked potentials, especially on magnetic valves as also used in our "Erlangen olfactometer". Several newly constructed magnetic valves were tested; the best one (MV3) enables us to fulfill the following indispensable conditions for proper averaging by computer: precise onset and duration of stimulus, and shortest possible stimulus rise and fall times. Tactile artifacts were avoided by constant rinsing of the tongue with neutral water, in which the taste stimulus was embedded without turbulences. By recording and averaging the galvanic skin response (GSR) at the same time, its influence on GEPs was compensated. To evaluate successfully objective correlates of taste sensation in man is believed to be of great basic and clinical importance.

Animals↗
PubMed1987

Sensory nerve endings in the mucosa of the epiglottis--morphologic investigations with silver impregnation, immunohistochemistry, and electron microscopy.

This study was conducted in order to investigate the structure of sensory nerve endings of the human epiglottis and substance P immunoreactive nerve fibers of the canine epiglottis in relationship to physiologic functions of the larynx. The human epiglottis was observed by light microscopy (silver impregnation) and electron microscopy, and the canine epiglottis was studied by peroxidase-anti-peroxidase (PAP) immunohistochemistry. The results are summarized as follows: (1) In the membranes of the epiglottis, we observed free endings of simple or complex tree shape, corpuscle endings with glomerular patterns, and taste-bud-like structures, and (2) electron microscopic studies revealed varicosity of the terminal axon with processes that contained small, clear and large, dense cored vesicles. Substance P was observed in these structures, and it was suggested that substance P was related to perception in the larynx.

Animals↗
PubMed1987

Substance P immunoreactive nerve fibers of the canine laryngeal mucosa.

Substance P (SP) immunoreactive nerve endings in the laryngeal mucosa were studied by PAP immunohistochemistry with light and electron microscopy. SP immunoreactive sensory endings were observed in the epithelium as intra-epithelial free nerve endings and taste bud-like structures. A small number of autonomic SP immunoreactive nerve fibers were observed running parallel to arterioles which were over 30 micron in diameter and terminated in glandular cells. Contrary to findings by silver impregnation, intraepithelial free nerve endings were more frequently observed on the lower surface of the vocal cord. The taste bud-like structures were classified into two different types: simple terminations and reticular terminations, according to the mode of the SP immunoreactive nerve fiber. Immature or degenerated taste bud-like structures in the larynx were assumed to be mechanical receptors because these receptors lacked outer taste pores and taste hairs.

Animals↗
PubMed1986

Bio-medico-mechanical behavior of natural artery blood vessel under constant and variable internal pulsatile pressure flow test in vitro.

Studies have been carried out on the bio-medico-mechanical behavior in vitro of natural blood vessel (dogs) under constant and variable internal pulsatile pressure flow. The apparatus designed by us well simulated the arterial system. The studies were made for the case of pressure amplitude kept as constant, of the two-step-multi-duplicated pulsatile pressure and of the fluctuating pressure. For the case of the fluctuating pressure, the strength of the artery becomes considerably lower than those under constant amplitude and two-step-multi-duplicated pulsatile pressure. SEM observations of the inner walls of the artery shows that collagen fibers are more elongated under fluctuating pulsatile pressure flow. In conclusion, in order to avoid the mechanical deterioration of the artery strength, it is useful to keep the pulsatile blood pressure at constant amplitude. Even for the case of the blood pressure fluctuation, it is necessary to manage to keep the blood pressure as near a regular wave as possible, the total number of repeated pulse being equal.

Animals↗
PubMed1986

The effect of a macrolide antibiotic against experimental sinusitis.

The effect of a macrolide antibiotic on experimentally induced sinusitis in rabbits was evaluated. Compared with the control group, the effect on sinus mucosal pathology was significantly superior in the drug-treated groups. Inflammation models as used in the present study will contribute to the establishment of a suitable pharmacotherapy for sinusitis.

Animals↗
PubMed1983

[Clinical evaluation of ototoxicity associated with intravenous drip infusion of amikacin].

On the 53 patients with ENT (ears, nose, and throat) diseases, ototoxicity after intravenous drip infusion of amikacin (Biklin AMK) was studied. Each dose of AMK was 400 mg/day in adults and 4--8 mg/kg/day in children. From audiometric analysis, there were no patients with any hearing disturbances and subjective complaints concerning labyrinth injury. Also abnormal laboratory findings were not found in them. An intravenous drip infusion of AMK in adequate dosage would be beneficial to use against some infectious diseases of otorhinolaryngologic field.

Adolescent↗