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Featured researches published by Koichi Ushiro.


Acta Oto-laryngologica | 1993

Kinetics of Epidermal Growth Factor in Saliva

Motoko Ino; Koichi Ushiro; Chiyonori Ino; Toshio Yamashita; Tadami Kumazawa

Human epidermal growth factor (hEGF) stimulates the growth and differentiation of various tissues. We measured EGF levels in saliva (n = 128), urine (n = 94), and serum (n = 99) with radioimmunoassay in order to study the kinetics of hEGF in saliva of normal subjects and patients with oral disease. Salivary EGF levels showed an apparent diurnal rhythm related to the taking of meals. Urinary and serum EGF levels showed no obvious diurnal rhythm. There was no significant correlation between salivary and urinary EGF levels, nor between salivary and serum EGF levels. Salivary EGF levels were significantly lower in the younger group (0-9 years old, 3.06 +/- 0.32 ng/ml, p < 0.05) than in the elder group (10-79 years old, 4.78 +/- 3.5 ng/ml), but did not correlate with age in the elder group. There was no significant difference between males and females between EGF levels in saliva, urine or serum. The relative proportion of EGF levels in submandibular gland saliva, parotid saliva, and whole saliva was 1:6:4. The positive rate of immunohistochemical EGF showed no significant differences between submandibular gland, parotid gland, sublingual gland or minor salivary gland. Salivary EGF levels were markedly low in patients with oral inflammations (stomatitis aphthosa, or peritonsillar abscess) or head and neck tumors (squamous cell carcinoma of the tongue, oral cavity, hypopharynx or larynx). These findings may be significant pathophysiologically. Low salivary EGF levels may reduce the capacity of oral mucosal defense mechanisms to fight against injury by physiochemical agents.


Acta Oto-laryngologica | 1981

Experimental Study of the Pumping Function of the Eustachian Tube

Iwao Honjo; Nobuhiro Okazaki; Tsuneki Nozoe; Koichi Ushiro; Tadami Kumazawa

To determine the muscle responsible for the pumping function of the Eustachian tube and to examine the detailed processes of this function, we conducted (1) a measurement of tympanal pressure during swallowing and during selective stimulation of the tensor and the levator muscles, and (2) visual and radiographic observation of fluid in the tube; in cats, dogs and a monkey. the results were: (1) formation of negative pressure in the tube by contraction of the tensor muscle; and (2) displacement of the fluid from the tympanum to the pharynx through the tube by repeated contractions of the tensor. It was concluded that contractions and relaxations of the tensor muscle cause the pumping function of the tube, which expells any fluid from there into the pharynx.


Acta Oto-laryngologica | 1993

Enhanced MRI in Patients with Ramsay-Hunt's Syndrome

Masahiro Yanagida; Koichi Ushiro; Toshio Yamashita; Tadami Kumazawa; Tsutomu Katoh

Enhanced MRI was performed in 14 patients with Ramsay-Hunts syndrome to investigate the pathogenesis of this syndrome. All MRI studies were performed on a 0.5T superconductivity MRI system using a head coil with Gd-DTPA. Enhancement was observed in the areas of the distal internal auditory canal and labyrinthine segment in many patients, and was especially prominent in patients suffering from vertigo, tinnitus, and hearing loss. In some patients it involved not only the facial nerve of the internal auditory canal but also the cochlear nerve and vestibular nerves. Since histological changes of the facial nerve in patients with Ramsay-Hunts syndrome are assumed to occur in the distal internal auditory canal and labyrinthine segment, which is more proximal than the geniculate ganglion, and the possibility is suggested that inflammation may spread to the vestibular and cochlear nerve via the internal auditory canal.


Acta Oto-laryngologica | 1993

Otitis Media with Effusion and Eustachian Tube Dysfunction in Adults and Children

Tadashi Iwano; Takuya Kinoshita; Eimoto Hamada; Tadashi Doi; Koichi Ushiro; Tadami Kumazawa

Eustachian tube (ET) function was studied in 162 ears with otitis media with effusion (OME) and chronic otitis media (COM), using tubo-tympanoaerodynamic graphy, patency and pressure equilibration test in the inflation-deflation test. Severe impairment of active opening function was found in both OME children and adults compared with that of COM patients. This impairment in active opening was thought to result from functional obstruction of the ET in 71.8% of OME children and 51.8% of OME adults. However, 45.6% of OME adults had an organic obstruction while such was present only in 28.2% of OME children. We deduce from this study that impaired active opening function of the ET in both OME children and adults is the result of functional obstruction rather than organic obstruction, but organic obstruction is considered to be related to the pathogenesis of OME in adults.


European Archives of Oto-rhino-laryngology | 1983

Cineroentgenographic and electromyographic studies of Eustachian tube function

Iwao Honjo; Koichi Ushiro; Tsuneki Nozoe; Nobuhiro Okazaki

ZusammenfassungZur Feststellung des Öffnungs- und Schließungsvorganges der Tube während des Schluckens wurden an drei Affen simultan das Röntgenkinematogramm und das Elektromyogramm registriert. Dabei zeigte sich, daß sich die knorpelige Tube synchron zur Aktivität des M. tensor veli palatini für ca. 250 ms durch eine Bewegung der lateralen Wand nach außen öffnet. Daneben erweitert sich die pharyngeale Tubenöffnung für eine relativ lange Zeit synchron mit der Aktivität des M. levator veli palatini. Diese Zeitverzögerung zwischen den beiden Tubenabschnitten scheint die Pumpfunktion der Tube zu unterstützen.SummaryTo determine the opening and closing process of the Eustachian tube during swallowing, the simultaneous recording of cineroentgenograms and electromyograms (EMG) was carried out in three monkeys. It was revealed that synchronous with the activity of the tensor veli palatini muscle, the cartilaginous tube opened for a very short time (ca. 250 ms) by an outward movement of its lateral wall. On the other hand, the pharyngeal orifice of the tube dilated for a relatively long time synchronous with the activity of the levator veli palatini muscle. These time lags between two parts of the tube seemed to help the pumping function of the tube.


Acta Oto-laryngologica | 1993

Eustachian Tube Function Tests and their Diagnostic Potential in Normal and Diseased Ears

Tadami Kumazawa; Tadashi Iwano; Koichi Ushiro; Takuya Kinoshita; Eimoto Hamada; Akihiro Kaneko

We have summarized various methods for testing Eustachian tube function since the 1980s. There have been numerous contributions to our knowledge on Eustachian tube and middle ear functions, and the pathophysiology of disorders of the middle ear has been clarified. Understanding of the Eustachian tube function and controlling the Eustachian tube dysfunction are mandatory for adequate clinical management and for improvement of the prognosis.


Acta Oto-laryngologica | 1993

Active opening function of the human eustachian tube: comparison between sonotubometry and pressure equilibration test.

Tadashi Iwano; Koichi Ushiro; Naoya Yukawa; Tadashi Doi; Takuya Kinoshita; Eimoto Hamada; Tadami Kumazawa

Sonotubometry and pressure equilibration test are representative test methods to evaluate the active opening capacity of the Eustachian tube. We applied these tests to 72 ears with otitis media with effusion and 21 ears with chronic otitis media. In 73 ears, both tests showed identical results (11 ears with good active function and 62 ears with poor function). Twenty ears showed good active opening by sonotubometry despite inability to relieve applied negative pressure by swallowing. This inconsistency is believed to result from a too short duration of the tubal opening, by which sound is transmitted through the Eustachian tube, without pressure change in the middle ear cavity. We propose that sonotubometry is a suitable method of detecting impairment of the tubal active opening function, but that a good result by sonotubometry does not always indicate a satisfactory pressure equilibration capacity of the Eustachian tube.


Acta Oto-laryngologica | 1988

Clinical Evaluation of S-CMC Syrup Applied in the Treatment of Otitis Media with Effusion: Double Blind Comparative Test with Placebo

Tadami Kumazawa; Koichi Ushiro

We carried out a double blind comparative trial with placebo serving as control using 250 cases of infant otitis media with effusion (OME) in order to objectively evaluate the clinical usefulness of S-carboxymethylcysteine (S-CMC), an oral mucolytic agent, against OME. The results obtained were as follows. 1) Global improvement rate, when judged in items of overall improvement, was 79.8% in S-CMC group and 58.2% in placebo group, S group being significantly better when compared to P. 2) The degree of improvement in each item for evaluation revealed significantly better results in S group compared to P, in both objective findings of the effusion amount and its property, and in audiological findings. 3) Adverse reactions observed in 3 cases (2.5%) in S group and in 2 (1.5%) in P group were not serious, and were eliminated through suspension or discontinuation of the medication. The results obtained suggested the usefulness of S-CMC when used in the treatment of OME.


Plastic and Reconstructive Surgery | 1984

Evaluation of velopharyngeal closure by CT scan and endoscopy.

Iwao Honjo; Tokichiro Mitoma; Koichi Ushiro; Michio Kawano

Computerized tomography (CT) and endoscopy were used for the objective evaluation of velopharyngeal closure. In 19 patients with cleft palates and 9 normal subjects, CT scans of the velopharynx were made both at rest and during vowel phonation with a scanning time of 3.0 seconds and slicing width of 3 mm. At the same time, endoscopic observations of the velopharynx through the nose were carried out both at rest and during phonation. CT scan during phonation clearly demonstrated the mobility of the velopharynx, i.e., elevation of the soft palate, inward movement of the lateral pharyngeal walls, and protrusion of the posterior pharyngeal wall, in a single picture. Its disadvantage is exposure to x-rays and a rather complicated procedure. However, endoscopy is simple with no exposure to x-rays, but its disadvantage is occasional incomplete visualization because of the dead angle created by the elevated soft palate. Thus the combined use of CT and endoscopy can help to determine a rational choice of treatment for cleft palates.


Auris Nasus Larynx | 1991

Sensation of Ear Fullness Caused by Eustachian Tube Dysfunctions

Tadashi Iwano; Takuya Kinoshita; Eimoto Hamada; Koichi Ushiro; Toshio Yamashita; Tadami Kumazawa

One hundred and ninety-four patients with a sensation of ear fullness were examined with the audiometry, tympanometry, and tubotympanoaero-dynamic graphy (TTAG) as a eustachian tube ventilatory test. In 74 cases of 194, the eustachian tube dysfunction was thought to cause an ear fullness sensation and patulous tube was found in 19 patients which is more frequent than expected. Functional unbalance of the both eustachian tubes which results from minimum ventilatory disturbance on the complaining side was also thought to be one of the causes of this symptom. The eustachian tube dysfunctions like stenotic or patulous tube could not be fully diagnosed by the audiometry and tympanometry because most patients with the eustachian tube dysfunctions showed normal middle ear pressure measured by the tympanometry. From our study, it could be concluded that eustachian ventilatory test like TTAG was very available in the patient with an ear fullness feeling which is one of the most common symptoms in the otolaryngological field.

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Tadami Kumazawa

Kansai Medical University

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Tadashi Iwano

Kansai Medical University

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Yasuo Hosoda

Kansai Medical University

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Eimoto Hamada

Kansai Medical University

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Tadashi Doi

Kansai Medical University

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