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T Fuse

Publications and source records attributed to T Fuse.

At least 55 records · Page 3Linked to original sources
PubMed1996

Delayed and progressive hearing loss after microvascular decompression of cranial nerves.

An unusual case of unilateral delayed and progressive hearing loss following a microvascular decompression operation on cranial nerves V, VII, and VIII on the left side is reported. Preoperative and postoperative audiologic evaluation revealed a mild high-frequency hearing loss for both ears, normal thresholds for the acoustic middle ear reflex response, and normal brain stem auditory evoked potentials. Three years after this microvascular decompression procedure, the patient noticed slowly decreasing hearing in her left ear, and subsequent serial audiograms revealed a progressive sensorineural hearing loss and a decrease in her speech discrimination score. Brain stem auditory evoked potentials showed progressive changes. Because of the patient's increasing symptoms of vertigo and tinnitus in the left ear, reexploration of the eighth cranial nerve was performed 5 1/2 years after the initial procedure. This second operation revealed reactive tissue around the eighth cranial nerve that was atrophic and yellow. We interpret the delayed and progressive hearing loss to be a result of reactive scar tissue and progressive atrophy of the auditory nerve.

Cicatrix↗
PubMed1996

[Problems encountered with a programmable pressure valve (SOPHY) positioned in the chest wall].

Sixty-eight hydrocephalic patients were treated with a shunt system that incorporated a SOPHY programmable valve. This device is very effective for treating disorders of CSF circulation. However, when the valve is placed on the scalp, it produces artifacts on MR imaging due to its small magnetic rotor, and may cause necrosis of the scalp above it. On the other hand, when it is positioned on the chest, MR artifacts decrease and exchanging the valve devices becomes easier. Therefore, we have positioned the device on the chest. However, some complications were encountered, such as the turning over of the valve in the subcutaneous pocket and the twisting of the shunt tube. Moreover, the shunt tube may stretch due to growth of the neck during development in infantile patients or extension of the neck during exercise. These complications are associated only with subcutaneous placement on the chest, so we conclude that such a valve, if placed on the chest, should be placed in a lower position on the chest, and if MR examination will not be performed in the foreseeable future, we recommend that it be placed on the occipital scalp, especially in infantile patients.

Aged↗
PubMed1996

Frequency specificity of 80-Hz amplitude-modulation following response.

The usefulness of 80-Hz amplitude-modulation following response (AMFR) detected by phase coherence to predict the hearing threshold during sleep was evaluated in 90 ears of 53 children with hearing impairment. The threshold of 80-Hz AMFR at carrier frequency of 1,000 Hz and the threshold of auditory brainstem response (ABR) elicited by 1,000 Hz tone pips in children during sleep were compared with behavioral hearing threshold, which was determined by standard pure-tone audiometry or play audiometry. In 12 ears of 12 children with various patterns of hearing impairment, 80-Hz AMFR at different carrier frequencies were examined, and the threshold pattern was compared with the pure-tone audiogram to investigate the frequency specificity of 80-Hz AMFR detected by phase coherence. The mean and standard deviation of the difference between 80-Hz AMFR and pure-tone thresholds was 4.3 and 12.1 dB, respectively, and that between ABR and pure-tone thresholds was 6.6 and 14.2 dB, respectively. The threshold patterns of 80-Hz AMFR very closely resembled the corresponding audiogram patterns in all types of hearing impairment. The measurement of 80-Hz AMFR in children during sleep thus appeared to be more accurate in hearing prediction than that by ABR elicited with tone pips and to have a good frequency specificity.

Adolescent↗
PubMed1995

A novel Ti-plasmid-convertible lambda phage vector system suitable for gene isolation by genetic complementation of Arabidopsis thaliana mutants.

A new lambda phage vector system, lambda TI, has been constructed to facilitate genetic complementation of higher plant mutations. The lambda TI vectors are stable, and by using the Cre-lox site-specific recombination, are automatically convertible into Ti-plasmid binary vectors which are capable of expressing genes in higher plants. Two lambda TI vectors were constructed: (i) lambda TI1, which can generate a Ti-plasmid that contains the cauliflower mosaic virus (CaMV) 35S promoter and is suitable for the expression of cDNA in transformed plants and (ii) lambda TI2, which can generate a Ti-plasmid with the multicloning site (MCS). cDNA and genomic libraries, which were constructed from the cruciferous plant Arabidopsis thaliana in these lambda TI vectors, can be probed by large DNA fragments of more than 100 kb, such as yeast artificial chromosomes (YACs), enabling the direct screening of the clones in the chromosome region containing a specified genetic locus. These libraries will certainly become powerful tools for the genetic complementation of Arabidopsis mutant phenotypes by quickly providing transformation-competent clones.

Agrobacterium tumefaciens↗
PubMed1995

Primary intracranial epithelioid angiosarcoma--case report.

A 39-year-old male presented with an exceedingly rare primary intracranial epithelioid angiosarcoma in the right parietal lobe manifesting as weakness of the left hand. Neuroimaging revealed a well-defined intensely enhanced lesion in the right parietal lobe with peripheral cerebral edema. The tumor was grossly totally removed. Light microscopy of the surgical specimens revealed features typical of an epithelioid vascular tumor. The tumor cells showed intense positive immunohistochemical staining for cytokeratin and vimentin and focally positive staining for both Ulex europaeus agglutinin and anti-human endothelial cells, CD31. Tumor regrowth required two further operations. This progressive growth was consistent with an angiosarcoma. The tumor was diagnosed as an epithelioid angiosarcoma based on the histological and clinical characteristics. He became progressively obtunded and finally died. This is the first intracranial epithelioid angiosarcoma which expressed epithelial markers detectable by immunohistochemical methods.

Adult↗
PubMed1995

[Primary intracranial malignant epidermoid--case report].

Intracranial malignant epidermoid is uncommon. We report a case of a 74-year-old woman with a primary intracranial malignant epidermoid in the parapontine region. The tumor was visualized as two components (a low-density benign prepontine lesion and a malignant enhanced cerebellopontine angle lesion) on CT scan. On MRI, the benign portion demonstrated low-signal intensity on T1 weighted images and markedly increased heterogeneous signal intensity on T2 weighted images, while the malignant portion showed iso-signal intensity on T1 weighted images that was markedly enhanced and heterogeneous signal intensity on T2 weighted images. Lack of contrast enhancement is a typical finding in benign epidermoid, although rim enhancement has been described in a few cases. In our patient, the contrast enhancement on CT scan in the otherwise typical epidermoid cyst suggested malignant degeneration. Using MR imaging, we could distinguish malignant epidermoid from benign epidermoid cyst more precisely.

Aged↗
PubMed1995

[A study of effective administration of recombinant interferon-gamma in renal cell carcinoma regarding immunological influence on peripheral blood lymphocytes].

Immunological effect of recombinant interferon gamma (IFN-gamma) was studied in 18 cases of renal cell carcinoma. Sixteen of them were administered IFN-gamma as post-operative adjuvant therapy. Two of them were administered IFN-gamma for metastatic renal cell carcinoma. All of them were followed for at least 1 year. We divided the patients into two groups. One group subcutaneously received IFN-gamma every other day for 16 days, then 4 weeks later every week for one year (group A), and the other group, received alternate subcutaneous IFN-gamma every other day for 16 days and every week for 4 weeks (group B). For immunological testing, peripheral blood lymphocytes were obtained before treatment on day 1, 2 weeks later, 6 months later and 12 months later. The cells were tested for natural killer activity (NK), antibody dependent cellular cytotoxicity (ADCC), positive lymphocytes of CD3, CD4, CD8 and CD11b. Both ADCC and NK activity were increased after therapy, especially in group B. CD3, CD4 and CD8 positive lymphocytes were increased by means of IFN-gamma. On the other hand, CD11b-positive lymphocytes could not be elicited in group B. Tumor regression was observed in 2 cases of metastatic renal cell carcinomas. When clinical responses were observed, both ADCC and NK were elicited as compared with the pretreatment values. Our findings indicated that ADCC and NK could be elicited in group B.

Adult↗
PubMed1994

Pure-tone threshold prediction by 80-Hz amplitude-modulation following response.

The usefulness of 80-Hz amplitude-modulation following response (AMFR) detected by phase spectral analysis to predict the hearing threshold during sleep was evaluated in 20 normal adults, 8 normal children and 37 children with hearing impairment. The onset effect of tonal stimulus on 80-Hz steady state response was studied in normal adults during sleep and a threshold of 80-Hz AMFR detected by phase spectral analysis was compared with that of ABR elicited by tone pips in children during sleep. Although 80-Hz AMFR is not appropriate for the assessment of hearing in adults, it appears useful for evaluating hearing in young children during sleep. Hearing prediction by 80-Hz AMFR appears to be more accurate than that by ABR elicited with tone pips. The onset effect of stimulus on 80-Hz AMFR with modulation depth of 95% was less than 80-Hz SSR evoked by clicks.

Acoustic Stimulation↗
PubMed1994

Effects of aging on amplitude-modulation following response.

Phase spectral analysis as developed by Fridman (1982) was used to detect amplitude-modulation following response (AMFR). The threshold of AMFR was determined with greater sensitivity and accuracy by phase spectral analysis than by visual analysis. Using this method, a modulation frequency (MF) of 80 Hz was found optimal for detecting AMFR in young children (ranging in age from 2 to 4 years) during sleep, for whom there is no advantage in recording 40-Hz steady-state responses. To determine the optimal MF for detecting AMFR during sleep in children less than 2 years of age and age limitation for using 80-Hz MAFR in objective audiometry, AMFR as a function of MF was investigated during sleep in 25 children with normal hearing ranging from 4 months to 15 years of age, and 10 normal hearing adults. The stimulus was a 1000 Hz, 50 dBnHL sinusoidally amplitude modulated tone with a modulation depth of 95%. MF was varied from 20 to 200 Hz in 20 Hz steps. Response was determined by phase spectral analysis and the S/N ratio calculated by spectral amplitude at the modulation frequency and noise level around the modulation frequency using fast Fourier transform. Phase spectral analysis showed AMFR at MF of 80 Hz to be the most stable and reliable in all children during sleep among MFs from 20 to 200 Hz. Spectral amplitude analysis demonstrated 80-Hz AMFR to have a high S/N ratio in all children.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustic Stimulation↗
PubMed1994

Effects of aging on hearing results in tympanoplasty.

The effects of aging on the preoperative and postoperative hearing results of tympanoplasty were assessed in 642 patients with chronic suppurative otitis media (COM) or cholesteatoma (CHL). Analysis focused on the correlation between hearing results and age for each disease and type of tympanoplasty. Data were evaluated by calculating the regression line, mainly using second order polynomial regression analysis. Averaged air and bone conduction thresholds (PTA) in patients were appreciably poorer in younger patients and increased with age, compared with physiological hearing impairment in old age (presbyacusis). Regression lines for PTA of air and bone conduction in patients and for normal data (air conduction) separated from each other after the age of 30 and hearing impairment gradually accelerated with age. Means of air-borne gap, however, were almost the same in each age group, though hearing thresholds in individual patients were distributed widely. This was more dominant in patients who had undergone type III or IV tympanoplasty than those with type I tympanoplasty, and in patients with COM than with CHL. Labyrinthine function thus appears to be gradually aggravated with age in patients with chronic inflammatory ear disease. Patients with chronic otitis media should be thus recommended to undergo tympanoplasty at an early age.

Adolescent↗
PubMed1994

Frequency analysis of transiently evoked otoacoustic emissions in sensorineural hearing disturbance.

Transiently evoked otoacoustic emissions (TEOAE) are present in nearly all normal hearing ears and recognized as useful for objective auditory screening. In the spectral analysis of TEOAE with click stimuli, the normal power spectrum of TEOAE has yet to be obtained. In this study, the normal range of the power spectrum was determined for 42 adults with normal hearing and compared with sensorineural hearing disturbance data. The power spectrum of TEOAE in normal hearing adults sloped down at high frequencies and was the same for right and left ears in both males and females. For comparison with sensorineural hearing disturbance, a significant correlation between the audiogram and power spectrum of TEOAE was sought. Frequency specificity was noted in the power spectrum of TEOAE with click stimulation.

Adult↗
PubMed1994

[Clinical trial of inhalant recombinant interferon-gamma in patients with pulmonary metastasis from renal tumor (preliminary report)].

Recently, we applied inhalation of recombinant interferon (IFN)-gamma, to 4 patients with pulmonary metastatic tumor (3 with renal cell carcinoma and 1 with renal pelvic tumor). Of the patients with renal cell carcinoma 2 had received previous nephrectomy, 1 patient had received embolization alone, 1 subcutaneous IFN-gamma in 1, and 1 systematic chemotherapy. All 4 patients inhaled 1 x 10(6) JR U-2 x 10(6) JR U recombinant IFN-gamma 3 times per day. Additionally, all metastatic renal cell carcinomas received subcutaneous injection of IFN-gamma. One patient with renal cell carcinoma achieved a complete response after inhalation therapy and 2 patients did not respond (NC: 1, PD: 1). A case of metastatic renal pelvic tumor did not respond. Immunohistochemical staining with antibody to Ber-MAC3 (stimulated macrophage) of this case revealed positive cells within the transitional cell carcinoma. According to these results, inhalation of IFN-gamma appears to be applicable as one treatment for pulmonary metastatic tumor of renal cell carcinoma.

Administration, Inhalation↗
PubMed1993

A gene encoding a chloroplast omega-3 fatty acid desaturase complements alterations in fatty acid desaturation and chloroplast copy number of the fad7 mutant of Arabidopsis thaliana.

Mutations at the fad7 locus of Arabidopsis thaliana (previously called fadD) cause decreased desaturation of dienoic fatty acids in chloroplast lipids in plants grown at elevated temperatures. This suggested that the fad7 locus encodes a chloroplast omega-3 desaturase that catalyzes the desaturation of lipid-linked 18:2 and 16:2 fatty acids. In order to clone the fad7 gene, it was first genetically mapped relative to the flanking restriction fragment length polymorphism markers 4547 and 2488A on chromosome 3, and yeast artificial chromosomes covering the locus were identified. A putative desaturase cDNA clone that was isolated by low stringency heterologous probing with a cDNA for an endoplasmic reticulum-localized omega-3 desaturase (fad3) hybridized to the yeast artificial chromosomes and could not be resolved from the locus by restriction fragment length polymorphism mapping. Expression of the cDNA in transgenic fad7 mutant plants resulted in restoration of wild type fatty acid composition and suppression of a previously observed effect of the fad7 mutation on chloroplast number, indicating genetic complementation. The structural gene contained seven introns within a coding sequence of 1338 base pairs, which encodes a 446-amino acid polypeptide of 51,172 daltons. The amino-terminal region of the fad7 gene product contained a consensus chloroplast transit peptide. Except for the amino-terminal domain, the deduced amino acid sequence of the fad7 gene product had high homology to the fad3 gene product, indicating that fad7 encodes an omega-3 desaturase and that the two genes arose from a common ancestral gene. There was no apparent effect of growth temperature on the steady-state levels of fad7 mRNA in wild type plants.

Amino Acid Sequence↗
PubMed1993

Optimal modulation frequency for amplitude-modulation following response in young children during sleep.

In young children, there appears to be no advantage to recording steady-state response (SSR) at a stimulus rate of 40 Hz. To determine the optimal modulation frequency in auditory SSR evoked by sinusoidally amplitude-modulated (SAM) tones (amplitude-modulation following response: AMFR) in children during sleep and compare response patterns of AMFR at different modulation frequencies while awake with those during sleep, AMFR was examined in 10 adults with normal hearing while awake and during sleep and in 10 young children with normal hearing during sleep. The stimulus was a 1000 Hz, 50 dBnHL SAM tone with a modulation depth of 95%. Modulation frequency was varied from 20 to 200 Hz in 20 Hz steps. Response was determined by phase spectral analysis and the S/N ratio calculated by spectral amplitude at the modulation frequency and noise level around the modulation frequency using fast Fourier transform. Although AMFR was clearly evoked only by a modulation frequency of 40 Hz in adults while awake, AMFRs at modulation frequencies of 80 and 100 Hz were detected during sleep, in addition to 40 Hz AMFR. In children, 40 Hz AMFR was difficult to detect, but response could be clearly detected at higher modulation rates, especially at modulation frequencies of 80 and 100 Hz, compared with response in adults during sleep. Modulation frequencies from 80 to 100 Hz would thus appear optimal for detecting AMFR during sleep in children.

Adult↗
PubMed1993

An application of phase spectral analysis to amplitude-modulation following response.

A phase spectral analysis developed by Fridman (1982) was applied to the detection of amplitude-modulated frequency following response (AMFR) and its clinical usefulness was evaluated. A 1000 Hz sinusoidally amplitude-modulated tone with a modulation frequency of 40 Hz and a modulation depth of 90% was delivered to the right ear of 10 normal-hearing subjects. According to Fridman's technique, an ensemble of sweeps was divided into 10 groups and group averages were obtained. Then phase variances were calculated using fast Fourier transform for the group averages. In order to determine the optimal conditions of analysis for constructing an automatic detection program using phase spectral analysis, frequency spacing, number of sampling points and number of sweeps averaged per group were investigated. The sensitivity of phase spectral analysis for automatic detection of AMFR was also evaluated. The results suggested that the optimal number of sampling points and frequency spacing are 512 points and 4.9 Hz (observation window 204.8 ms), respectively. Concerning the average number of sweeps, the synchrony measure of the frequency component corresponding to the modulation frequency increased as the number of sweeps increased. Furthermore, it was demonstrated that threshold determination by phase spectral analysis is more sensitive than detection of the threshold by visual analysis of waveform configuration.

Adult↗
PubMed1993

[Clinical application of transiently evoked otoacoustic emissions in screening for auditory dysfunction].

Transiently evoked otoacoustic emissions (TEOAE) should be used clinically as an objective and noninvasive screening test for auditory dysfunction in children. The features of TEOAE measured by "ILO88" with non linear click stimuli are discussed. The following results were obtained: 1) The normal range of a power spectrum was determined using 42 adults with normal hearing and compared with data for sensorineural hearing disturbance. The power spectrum of TEOAE in adults with normal hearing sloped downward at high frequency and was the same for right and left ears in both males and females. For comparison with sensorineural hearing disturbance, a significant correlation between the audiogram and power spectrum of TEOAE was sought. 2) Patients with otitis media with effusion (109 ears in 67 children) were examined by audiometry, tympanometry and TEOAE. The hearing disturbance threshold of 45 cases with TEOAE was lower than that in cases with no TEOAE. In tympanometry, low intratympanic pressure was noted in the absence of TEOAE. 3) TEOAE and spontaneous otoacoustic emission were examined in 42 adults with normal hearing and 27 neonates using the same probe and level of stimuli to clarify differences in TEOAE according to age. The amplitude of TEOAE and the highest peak of the frequency component at 4kHz in neonates exceeded those of adults. The peak stimuli recorded with the intracanal probe in neonates was also larger than that of adults. Three out of 15 neonates had spontaneous otoacoustic emission and essentially the same proportion was noted in young adults.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustic Impedance Tests↗
PubMed1993

[Regional phacomatosis with cerebral AVMs and cavernous hemangioma of the skull--report of a case].

We report the coexistence of multiple arteriovenous malformations (AVMs) and hemangioma of the skull in a 38-year-old man with associated varicose veins in his scalp. The patient also had hypotrophy of all right limb tissues with skin pigmentation and syndactyly of both feet. CT scans revealed intraventricular hemorrhage and a hemangioma of the skull at the posterior fossa. Because of the location of the arteriovenous malformations, surgical evacuation and resection were not attempted. The hemangioma was totally removed to decompress the posterior fossa. A few cases of regional phacomatosis with intracranial AVMs have been reported, but we could not find a report of the coexistence of intracranial multiple AVMs and hemangioma of the skull with associated varicose veins of the scalp and skeletal hypotrophy. We discuss on the etiology of the coexistence of regional phacomatosis and hemangioma and on the difference between our case and typical regional phacomatosis.

Adult↗