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Biomedical subjects

E Yanagisawa

Publications and source records attributed to E Yanagisawa.

At least 19 recordsLinked to original sources
PubMed1992

Determination of baicalin and baicalein in rat plasma by high-performance liquid chromatography with electrochemical detection.

A rapid and sensitive method, using electrochemical detection, has been developed for the determination of baicalin and baicalein, the flavonoid of Scutellariae radix, in rat plasma. Following separation by high-performance liquid chromatography, baicalin and baicalein were oxidized at a glassy carbon electrode to permit selective electrochemical detection. Absolute detection limits were found to be 5 ng/ml from 50 microliters of plasma for baicalin and 2 ng/ml from 100 microliters of plasma for baicalein. The resulting assays were suitable for pharmacokinetic studies of baicalin and baicalein in rats.

Animals↗
PubMed1992

Comparison of new telescopic video microlaryngoscopic and standard microlaryngoscopic techniques.

A new approach to microlaryngeal surgery using a specially designed video microlaryngoscope with a rigid endoscopic telescope and an attached video camera was introduced by Kantor et al in 1990. The ability to video document and perform surgery of the larynx by viewing a high-resolution television image was demonstrated. This method was recommended over the standard microscopic technique for increased visibility with greater depth of field, unimpeded instrument access, instant documentation, and superior teaching value. The authors tried this new method and the standard microscopic technique at the same sitting on a series of patients. This paper will compare these two different techniques and discuss their advantages and disadvantages. Although the new method has many advantages, the standard microscopic technique remains as a valuable method in laryngeal surgery.

Adult↗
PubMed1992

Changes in oxygen uptake-work rate relationship as a compensatory mechanism in patients with heart failure.

To assess the compensatory change in oxygen uptake (VO2) kinetics during exercise in patients with heart failure, we performed cardiopulmonary exercise testing using a cycle ergometer in 29 cardiac patients and 18 normal subjects. The work rate increased linearly (1w/6sec) after a 4 min, 20w warm-up. The ratio of increase in VO2 to increase in work rate (delta VO2/delta WR) was determined by linear regression of VO2 plots. Cardiac output by dye dilution method and plasma norepinephrine concentration (NE) were measured at rest and 20w warm-up. VO2 at rest and at 20w warm-up and delta VO2/delta WR decreased significantly with increasing severity in NYHA functional classification. delta VO2/delta WR showed significant negative correlation to the difference in NE levels at rest and at 20w (r = -0.69, p less than 0.001). The delta values of arteriovenous O2 content difference, calculated using Fick's principle, and cardiac index from rest to 20w warm-up failed to show significant relationship to delta VO2/delta WR. These results suggest that the decrease in VO2 requirement in heart failure patients is due probably to blood redistribution during exercise as a compensatory mechanism for exercise intolerance.

Adolescent↗
PubMed1992

The efficacy of aerobic exercise therapy on hypertensive patients with mild cardiac complications.

To investigate the antihypertensive efficacy of aerobic exercise therapy in essential hypertensives, 20 patients underwent eight weeks of cycle ergometer training at anaerobic threshold (AT) point. Cardiopulmonary exercise testings with ramp protocol were performed before and at two/four/eight weeks during the training period in order to determine AT and to evaluate the changes in blood pressure (BP), heart rate (HR), oxygen uptake (VO2; ml/min/kg), and O2 pulse (ml/min/beat) during exercise. 75g glucose tolerance test (OGTT) was measured before and after exercise therapy. The mean values of systolic blood pressure, oxygen uptake, O2 pulse, before and after exercise therapy were as follows: systolic blood pressure at rest = 160 +/- 19 mmHg and 135 +/- 11 mmHg, systolic blood pressure at AT = 195 +/- 13 mmHg and 180 +/- 10 mmHg, oxygen uptake AT = 12.0 +/- 0.9 ml/min/kg and 14.4 +/- 1.0 ml/min/kg, O2 pulse at AT = 6.8 +/- 1.5 ml/min/beat and 7.6 +/- 1.88 ml/min/beat. After exercise therapy, systolic blood pressure decreased (p less than 0.01), while O2 pulse and VO2 increased (p less than 0.01). Hyperresponse of serum insulin to glucose also improved. These results show that aerobic exercise therapy at AT level has beneficial effects on high blood pressure and improves exercise tolerance and hyperresponse of serum insulin to glucose without any complications.

Adult↗
PubMed1991

Supraglottic contributions to pitch raising. Videoendoscopic study with spectroanalysis.

Several questions pertaining to pitch raising recur frequently. Does the larynx rise with the production of higher frequencies? What happens to the pharyngeal walls between the soft palate and the larynx when the fundamental frequency is raised? How does the soft palate participate in pitch raising? To answer these questions, the present study was undertaken with the recently described simultaneous velolaryngeal endoscopy technique. Nine professional singers were asked to find the limits of their vocal range in any of six voice qualities: speech, falsetto, cry/sob, twang, belting, and opera. Simultaneous activities of the larynx, the pharyngeal walls, and the soft palate were submitted to videoendoscopy with synchronous voice recording and studied with spectroanalysis of discrete segments of the total phonation range. Our dual endoscopic study showed that 1) the larynx rose in all subjects with the production of higher frequencies, 2) with the highest fundamental frequency, the lateral pharyngeal walls significantly contracted toward the midline in an "upside-down V shape," creating a very narrow pharyngeal tube, and 3) the soft palate lifted and the velopharyngeal port narrowed considerably with higher frequencies.

Adult↗
PubMed1991

Laryngeal photography.

Various methods of still photography and videography of the larynx are described in this article, some simple, inexpensive, and recommended for residents and occasional laryngeal photographers, while others are more involved, costly, and recommended for serious laryngologists. The choice of a specific method depends upon the physician's need, the availability of the equipment, budget, and more importantly, photographic skill and imagination. Although still photography is a valuable method of laryngeal documentation today, videography increasingly is gaining favor. Because of its simplicity, reproducibility, time and cost effectiveness, and capacity to simultaneously record laryngeal images and voice, videography has distinct advantages and may someday replace still photography of the larynx.

Humans↗
PubMed1990

Role of the soft palate in laryngeal functions and selected voice qualities. Simultaneous velolaryngeal videoendoscopy.

The role of the soft palate in normal laryngeal functions and in the production of selected voice qualities was studied by a simultaneous velolaryngeal videoendoscopy technique. For this technique, the Olympus ENF-P flexible nasopharyngolaryngoscope was passed via one nostril to study the function of the larynx, while the Hopkins 70 degrees rhinoscopic telescope was passed via the other nostril to study the function of the soft palate and velopharyngeal closure. A Kay Elemetrics DSP Sona-Graph, model 5500, was used to analyze a complex vocal figure of five consecutive voice qualities, three of which were nasal, and two, oral. Simultaneous velolaryngeal videoendoscopy proved to be of great value for the understanding of the interaction of velar and laryngeal functions and for clarifying the mechanisms of nasal and twang qualities.

Adult↗
PubMed1989

Video nasopharyngoscopy: a comparison of fiberscopic, telescopic, and microscopic documentation.

Video nasopharyngoscopy is a most valuable method of documenting the anatomy and pathophysiology of the nasopharynx. Such a permanent record is useful for diagnosis, patient counselling, resident teaching, and the monitoring of therapy in nasopharyngeal disorders. To evaluate the various techniques for assessment of the nasopharynx, the authors have attempted to systematically compare flexible and rigid endoscopes and mirror examination during video recording. The pros and cons of 1) transnasal fiberscopic, 2) transnasal telescopic, 3) transoral telescopic, and 4) transoral microscopic mirror examination methods for video nasopharyngoscopy are discussed.

Adolescent↗
PubMed1987

Telescopic video-otoscopy using a compact home video color camera.

Our method of telescopic video-otoscopy using a telescope (Hopkins) and a compact home video camera is presented. Telescopic video-otoscopy is a most effective method of demonstrating and documenting the anatomy and pathology of the tympanic membrane, ear canal, and mastoid cavity. It is of considerable value for teaching, patient counseling, and making a permanent record. It obtains instantaneously a video print-out either in black-and-white or in color of video images of telescopic otoscopy. A simple and economical method of telescopic pneumatic otoscopy (pneumatic teleotoscopy) is also described. Telescopic video otoscopy combined with the use of a video printer is a useful addition to the clinical practice of otology.

Data Display↗
PubMed1986

Telescopic videorhinoscopy: a useful addition to the clinical practice of rhinology.

Telescopic videorhinoscopy using a rigid telescope and a color video camera is an effective method of demonstrating and documenting the anatomy and pathology of the nose. Its chief value is in making an accurate diagnosis. It is also an excellent method of teaching endoscopic surgery of the nose and sinuses. The authors present a useful method of telescopic videography of intranasal structures using Hopkins rigid telescopes and a reasonably priced video home system color camera. Telescopic videorhinoscopy is a useful addition to the daily practice and teaching of rhinology.

Endoscopes↗
PubMed1986

Instantaneous "video photography" with a low-cost black-and-white video printer: its value in otolaryngology and head and neck surgery.

Despite its shortcomings in black-and-white imagery and its print quality, the video printer described here is an inexpensive and convenient video image-printing instrument and is useful for documentation of anatomy and pathologic conditions of otolaryngologic structures. It is of great value in patient counselling and in development of a permanent pictorial record.

Head↗