The literature has reports on the influence of spontaneous otoacoustic emission (SOAE) on transiently evoked otoacoustic emission (TEOAE), but most do not take factors such as age, gender, and hearing level into considera-tion. We focused on these conditions.
Subjects were 78 women with normal hearing aged 19 to 24 years (mean=21.4). All had pure tone thresholds of 15dB HL or better at 1kHz, 2kHz, and 4kHz. ILO88 was used to record TEOAE and SOAE. Echo power (EP) and reproducibility (Repro) were compared between groups with and without SOAE. No significant audiometric difference was seen between groups. Total echo power (TEP) and whole reproducibility (WR) were significantly greater in the group having SOAE, consistent with previous reports (p<0.01). EP and Repro classified by frequency bands were also significantly greater in the group having SOAE at 1kHz to 4kHz. Subjects were divided based on the number of SOAE and the above parameters compared. We found that as the SOAE number increased, EP and Repro increased, In conclusion, the existence of SOAE influences TEOAE parameters and must be taken into account during clinical testing.

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The most common symptoms of patients with carcinomas of the middle ear or mastoid are otorrhea, facial paralysis, and hearing loss, including a sensorineural element and vertigo. The latter two symptoms are indicators of inner ear damage. However, few reports have been made concerning the histopathological changes that occur in the inner ear in the presence of a tumor. The present study was performed to determine the pattern of tumor invasion in the inner ear and the histopathological changes that occur in the inner ear in cases of ear carcinomas. Temporal bone sections from five patients (age: #39-73 years; 3 males and 2 females) who died from a primary carcinoma of the ear were studied histologically. The following features were examined: 1) localization of the tumor in the temporal bone, 2) pattern of tumor invasion in the inner ear, 3) pathological changes in the inner ear, including the cochlea, vestibule and semicircular canals. Tumor cells were still present in the temporal bone sections of all the patients except one, even though the patients had received various treatments for the carcinoma, including radiation therapy, surgery and chemotherapy. Marked inflammatory and necrotic changes were observed in cases where the tumor had invaded the external auditory canal, middle ear cleft, internal auditory canal, and in some cases the inner ear. In cases where the tumor invaded the inner ear via the internal auditory canal rather than directly from the middle ear, the otic capsule is thought to have acted as a barrier against tumor invasion. In addition, marked degenerative changes throughout the entire inner ear structures were noted. These changes may have arisen from an attenuated blood supply to the inner ear as a result of pressure from the tumor in the internal auditory canal, tumor infiltration of the labyrinthine artery.

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The distribution of metastatic foci in the opposite lobe has not been studied in detail despite of several reports on the high incidence of contralateral metastasis. Whether foci spread to the upper one-third of the contralateral lobe influences the choice of total or subtotal thyroidectomy. Metastasis was studied in 66 patients 11 men and 55 women aged 24-73 years (mean:51.3), undergoing primary total thyroidectomy from 1988 to 1996. Serial blocks of the opposite lobe, approximately 5mm thick were sliced and stained by hematoxylin-eosin. Metastases were found in 44 patients (67%). Based on the size of the primary focus, these patients were divided into group A (smaller than one-third of the lobe) and group B (greater than that of group A).
The average size of the primary focus was 21mm in group A and 36mm in group B. The contralateral metastatic rate was 64% (14/22) in group A and 68% (30/44) in group B. The distribution of metastatic foci in the opposite lobe was studied in 44 positive patients. The spread to the upper one third occurred in 61% (27/44); 29% (4/14) in group A and 76% (23/30) in group B a significant difference (p<.003).
We thus concluded that the larger the primary focus, the wider the spread of metastatic foci to the opposite lobe.

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While globus pharyngeus is a common disorder, the cause of this anomaly remains unclear. Gustroesophageal reflux, cricopharyngeal spasm, and many other etiologies have been considered as possible causes. Some researchers believe that the disorder is probably multifactorial in origin. Patients with globus pharyngeus are usually female, and the majority of them are menopausal. These middle aged females often have a reduced bone mineral density. This study was undertaken to determine whether males and females with globus pharyngeus have a reduced bone mineral density.
We studied 12 men and 17 women with globus pharyngeus who came to Tokai University, Isehara Kyodo Hospital and the Hagino E. N. T. Clinic between February 1992 and February 1994 and compared them to a control group of 12 males and 15 females. Each patient met the criteria for 'primary globus pharyngeus' (Bradley 1987) as determined by endoscopy and none of the patients showed any signs of inflammation, tumors, or gastroesophageal reflux. The second midcarpal bone mineral density of each subject was measured using a computed X-ray densitometer and analyzed using microdensitometry.
Compared with control group, patients with globus pharyngeus had a lower bone mineral density in their second mldcarpal bone. The ΣGS/D was significantly lower in the globus pharyngeus patients than in the control group (p<0.01) and significantly lower in the female patients than in the female control group (p<0.01). The GSmax was significantly lower in the patients than in the control group (p<0.01) and significantly lower in the female patients than in the female control group (p<0.01). The GSmin was significantly lower in the patients than in the control group (p<0.01), significantly lower in the female patients than in the female control group (p<0.01), and significantly lower in the male patients than in the male control group (p<0.05).
In conclusion, globus pharyngeus appears to be related to a decrease in bone mineral density.

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CNV (contingent negative variation), an event-related potential, is induced when an oncoming imperative stimulus (S2) is anticipated after recognition of a warning stimulus (S1). With this in mind, we assessed the usefulness of electrogustometry using CNV as an objective gustatory test with an electric gustatory stimulus as a warning stimulus, S1
A gustatory test was performed on a total of 100 sides of the tongue in 50 subjects. Excluding no response cases on 5 sides in 5 subjects, the CNV threshold was successfully determined on 95 sides in 50 subjects. When the CNV threshold values obtained and the conventionally measured subjective threshold values were compared, a very high correlation was demonstrated between the two thresholds, with a correlation coefficient of 0.961. To assess the reliability of the CNV threshold, three additional measurements on 5 sides in 5 subjects with normal subjective threshold values were performed on different days, and the CNV threshold value variation among the three measurements in all 5 subjects never exceeded 13μA. Separately, subjective threshold and CNV threshold values were compared in 4 patients with facial palsy (hence with gustatory abnormality) who consented to a follow-upexamination. The difference between the subjective threshold and CNV threshold values in all 4 patients never exceeded 10μA. These findings demonstrate that the reliability of the CNV threshold is satisfactory.
Next, a gustatory imitation experiment was performed to assess the usefulness of electrogustometry using CNV as a means of detecting gustatory abnormality malingering. The experiment was performed on a total of 6 subjects: 3 physicians with knowledge of CNV (knowledge group) and 3 others with no knowledge of CNV (no-knowledge group). The differences between the imitated threshold and the subjective threshold values in all of these subjects never exceeded 10μA, and the difference between imited threshold and CNV threshold values never exceeded13μA. Comparison between the knowledge group and the no-knowledge groups showed that the imitated threshold values were very close to the subjective threshold and CNV threshold values.
Based on the above results, it was concluded that gustometry using CNV is useful and can serve well as a method of objective evaluation of gustatory sensation. The results also suggested that it will be useful in diagnosing malingering.

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Various types of carcinoma cells have been shown to escape immune recognition by constitutive resistance to Fas receptor (Fas)-mediated apoptosis. The purpose of this study was to examine the sensitivity to Fas-mediated apoptosis of human head and neck squamous cell carcinoma (HNSCC) cells. We applied an anti-Fas monoclonal antibody (CHll) to HNSCC cell lines and monitored their cell death. All three HNSCC cell lines examined expressed Fas protein but not Fas-ligand mRNA. CHll did not induce cell death (CHll-resistant) in any of the three HNSCC cell lines examined. Treatment with actinomycin D (ActD) converted the phenotypes of the CHll-resistant HNSCC cell lines from CHll-resistant to CHll-sensitive, suggesting that the resistance to CHll-induced apoptosis was dependent on RNA synthesis. Western blot analysis did not show any differences in expression of Bcl-2 between the non-treated and ActD-treated HNSCC cell lines. Expression of Bcl-XL, on the other hand, was greatly reduced in the ActD-treated HNSCC cell lines, implying that Fas signaling in the CHll-resistant HNSCC cell lines might be regulated by an Bcl-XL-inhibitable step.

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Paclitaxel has been reported to be effective for the treatment of CDDP resistant tumors. Thus, the efficacy of paclitaxel on CDDP resistant HEp-2 and KB head and neck squamous carcinoma cell lines was evaluated in monolayer and multicellular tumor spheroids (MTS). Cell lines with a tenfold resistance to CDDP were used in this study (Tanaka, K. et al, Keio J Med, 70. 1993). MTS were developed using the liquid overlay culture technique. After exposure to graded concentrations of drugs and different exposure time, the cells were subjected to a clonogenic assay. The effect of paclitaxel on both monolayer and MTS was dependent on the drug concentration and related to the exposure time. For HEp-2 MTS, 10-7M/L of paclitaxel resulted in a cell death rate of approximately 90% in both parent and resistant cells. For KB MTS, the cells were more resistant to paclitaxel than the HEp-2 cells, and a 72 hour exposure time was needed to achieve a cell death rate of approximately 90%. These data suggest that paclitaxel may be effective for treating CDDP resistant head and neck cancer.

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The vestibulo-ocular reflex (VOR) serves to stabilize images on the retina. To maintain appropriate perfor-mance and minimize image slippage throughout life, the VOR is subject to long-term adaptive regulation in response to visual input. Adaptive changes in VOR gain (eye velocity/head velocity) can be evboked either by fitting subjects with magnifying, miniaturizing, or reversing spectacles during normal behavior or by moving a large visual field in or out of phase relative to the subject's head movement. These changes exhibit frequency-selectivity. Here, we examine the flexibility of VOR gains by causing VOR in similar directions to undergo different behavioral gain changes.
Nine healthy adults, ranging in age from 24 to 38 (mean 28.5) with no history of neurotological symptoms participated in the study. All subjects demonstrated clinically normal functioning on a screening battery of tests that included combined neurologic and otologic physical examinations. Horizontal and vertical eye positions were recorded by bitemporal DC coupled electrooculography (EOG). The subject sat in a rotating chair. The axis of rotation of the body was always earth-vertical, the interaural axis crossing the axis of rotation of the chair. The head was positioned at 20degrees down in all experiments and was stabilized in this position using a chin rest. The chair was 78cm in diameter and was shielded by a half-cylindrical optokinetic screen positioned in front of the subjects. Random dot patterns were projected onto this screen. During per- and postadaptation periods, goggles were fitted to ensure that the subject was in complete darkness and the chair was rotated sinusoidally. The amplitude of the rotating chair was 30degrees and 60degrees. Frequencies of rotation were 0.1Hz, 0.2Hz, 0.3Hz and 0.4Hz for amplitudes of 30degrees and 0.1Hz, 0.2Hz, and 0.3Hz for amplitudes of 60degrees. To induce VOR adaptation, the retinal slippage velocity caused by the visual input of a large field was changed for short-term; the change was produced by a combination of sinusoidal head rotation and random dot patterns. During each adaptation session, the frequencies of sinusoidal head rotation were either 0.1Hz or 0.3Hz and the amplitude was 30degrees. The random dot patterns were synchronized with the sinusoidal head rotation in the same direction to make the retinal slippage zero (x0 experiment) and in the opposite direction to double the retinal slippage (x2 experiment). Therefore, a total of four adaptation protocols were tested. The subjects were asked to fix their eyes on a single dot by looking straightahead in the x0 experiment and to follow the dot in the random dot pattern in the x2 experiment. Each adaptation session lasted for 30 minutes. Each subject participated in couple of adaptation experiments everyday. The average VOR gain and phase lag were calculated using a Fourier transformation.
Out of all the subjects who participated in the x2 adaptation experiment at 0.3Hz with an amplitude of 30degrees, seven subjects showed a steady increase in VOR gain during a couple of the trials. One out of the remaining two subjects showed a decrease in VOR gain in all three trials. Another subject showed an increase in VOR gain during three trials and a decrease in two trials. In the x2 adaptation experiment with a range of 30degrees at 0.3Hz (peak velocity: 28degrees/s), the percent change in gain (post-pre/pre) was 133% at the same stimula-tion and 100% at 0.4Hz (peak velocity: 37degrees/s). The percent change in gain was 65% for amplitudes of 60degrees at 0.1Hz (peak velocity: 18degrees/s) and 64% for amplitudes 60degrees at 0.2Hz (peak velocity: 37degrees/s). In the x1 adaptation experiment (30degrees at 0.3Hz), the percent change in gain was -62% for the same conditions and -50% for amplitude of 60degrees at 0.1Hz and -30% for amplitudes of 60degrees at 0.2Hz. No change, in VOR gain was observed at the other frequencies.

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