Biomedical subjects

Hideyuki Honda

Publications and source records attributed to Hideyuki Honda.

4 recordsLinked to original sources

PubMed2005

An analytical system for determining delta17O in CO2 using continuous flow-isotope ratio MS.

We developed a simple measurement system for delta17O in nanomole quantities of CO2 using continuous flow isotope ratio mass spectrometry (CF-IRMS). The analytical system consisted of a sample injection system, a helium-purged CO2 purification line, a capillary GC, a combustion unit, and CF-IRMS. A unique feature of the system is that we use molecular CO2 to determine the isotopic compositions including delta17O. The delta17O of CO2 in a sample is calculated from the mass ratios of both 45/44 and 46/44 of two different kinds of CO2, which have been purified quantitatively from different aliquots of a sample. While one aliquot (rCO2) flows into IRMS directly, the other (eCO2) flows through a CuO unit (900 degrees C) prior to injection into IRMS, to exchange oxygen atoms in the sample CO2 molecules with those in CuO for which we can assume Delta17O = 0. In our system, we introduce both rCO2 and eCO2 alternately to IRMS repeatedly by using an automatic multianalytical system to improve analytical precision statistically. The standard deviation of 0.35 per thousand for Delta17O can be realized using as little as 8.7 nmol CO2 in a approximately 3-h analysis. Based on this system, we have quantified delta17O in the stratospheric CO2 over Japan.

Journal Article↗

PubMed2005

[Bilaterality in acute low-tone sensorineural hearing loss].

Bilaterality in acute low-tone sensorineural hearing loss (ALHL) is more generally recognized than that in idiopathic sudden sensorineural hearing loss. Subjects were 274 patients diagnosed with ALHL based on criteria of a study group of the Ministry of Health, Labor and Welfare of Japan, i.e., total of 3 low tone hearing of 70dB or more and, a total of 3 high-tone hearing of 60dB or less, and treated at the departments of otolaryngology at Yamanashi University and Suwa Central Hospital. ALHL involving bilateral ears symptoms and/or bilateral hearing impairment conforming to diagnostic criteria was selected and summarized. Clinical ear symptoms, clinical test results, and hearing levels (total 3 low tone hearing, 1kHz, and total of 3 high-tone hearing) were statistically analyzed. We also reviewed Japanese clinical reports of ALHL that include bilateral cases. In 32 cases (11.7%) of 274 cases, both ear symptoms and hearing impairment were bilateral. In 22 (8.0%) of the 274, bilateral ear symptoms were present, but showed unilateral hearing loss conforming to diagnostic criteria. Another 22 (8.0%) out the 274 reported unilateral ear symptoms, but hearing tests indicated bilateral ALHL. A total of 76 cases (27.7%) of the 274 had bilaterality in either ear symptoms or hearing loss. Our review indicated that 9.0% (162 of 1803) ALHL patients were bilaterally affected, possibly indicating that AIHL includes a larger number of bilateral cases than currently assumed, if the opposite side were given a especially detailed clinical interview. Statistical analysis (Mann Whitney test, P<0.01) of hearing of unilateral cases indicated that 3 low tone hearing was more affected than 3 high-tone hearing, even on the normal side. These results indicate that ALHL tends to be bilateral, possibly due to the mechanism of pathogenesis, and also that the mechanism may include both local and general conditions. This more closely resembles Meniere's disease than idiopathic sudden sensorineural hearing loss. Both sides of bilateral cases were not usually the same in hearing patterns, glycerol test results, or prognosis. A statistically significant difference (Mann Whitney test, P<0.01) in total of 3 low tone hearing was seen between worse and better sides in bilateral cases. The degree of disease on both sides in bilateral cases thus was not always the same. Bilateral cases may result from both the influence of general conditions such as fatigue, stress, and lack of sleep and local conditions such as pathogenesis of endolymphatic hydrops that may cause differences in both ears. No clear difference was seen in clinical symptoms, hearing levels, and clinical examination, e.g., Schellong and glyceol tests, between unilateral and bilateral cases. Bilateral cases had a poorer prognosis (lower complete recovery ratio; chi2 test P<0.01) than unilateral cases. Our results indicated that cautious evaluation of opposite ear is necessary in diagnosis, treatment, and prognostication of ALHL.

Acute Disease↗

PubMed2003

Carbon dioxide laser vaporization of the inferior turbinate for allergic rhinitis: short-term results.

Carbon dioxide laser vaporization of the turbinate has recently become accepted as a common treatment for allergic rhinitis. Usually, only a single procedure is applied to minimize trauma. However, repeated procedures on separate days are often required to achieve an adequate effect. Therefore, we attempted a new method of vaporization and evaluated the outcome, and also tried to determine which patients have good indications for laser treatment. To widely and deeply vaporize the inferior turbinate, we repeated the procedure 3 times in 1 session after removing the carbon coating from the previous vaporization under nasal endoscopic observation. After the procedure, most patients experienced complete nasal obstruction for 2 or 3 days, but there was no intraoperative or postoperative bleeding or severe pain. All patients obtained improvement of their chief complaints and were satisfied 2 months after the operation. In particular, 60% of the patients were completely relieved of refractory nasal obstruction. Most patients were more satisfied with the effects than are those treated by the usual methods. Completely successful cases (improvement in all symptoms and complete satisfaction obtained) were selected and were compared with other cases. Favorable prognostic factors are more severe complaints, longer symptomatic periods, stronger allergic reactions, and worse nasal resistance and its greater improvement with administration of decongestant nasal drops. This method may be especially accepted by patients with severe complaints, in particular nasal obstruction, who do not experience enough relief with conservative therapies or have enough time to make frequent visits to an outpatient clinic over a period of several weeks.

Adolescent↗

PubMed2002

Clinical study of acute low-tone sensorineural hearing loss: survey and analysis of glycerol test and orthostatic test.

Fifty patients (14 men and 36 women ranging in age from 16 to 66 years) with acute low-tone sensorineural hearing loss (ALHL) were retrospectively analyzed in this study. The glycerol test and the orthostatic test were performed. On the glycerol test, 43.8% of 16 ears of the 14 men and 33.3% of 39 ears of the 36 women with ALHL had a positive result. On the orthostatic test, 42.9% of the 14 men and 52.7% of the 36 women with ALHL had a positive result. In addition, 28.6% of the 14 men and 33.3% of the 36 women had hypotension with a systolic blood pressure of 100 mm Hg or less. Our results suggest that endolymphatic hydrops as shown by the glycerol test and an underlying autonomic imbalance and/or insufficient blood circulation as shown by the orthostatic test may be important factors in the causation of ALHL.

Acute Disease↗