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Biomedical subjects

K Misaki

Publications and source records attributed to K Misaki.

At least 19 recordsLinked to original sources
PubMed2000

Iron K Line Variability in the Low-Luminosity Active Galactic Nucleus NGC 4579.

We present results of new ASCA observations of the low-luminosity active galactic nucleus (LLAGN) NGC 4579 obtained on 1998 December 18 and 28, and we report on the detection of variability of an iron K emission line. The X-ray luminosities in the 2-10 keV band for the two observations are nearly identical (LX approximately 2x1041 ergs s(-1)), but they are approximately 35% larger than that measured in 1995 July by Terashima et al. An Fe K emission line is detected at 6.39+/-0.09 keV (source rest frame), which is lower than the line energy 6.73+0.13-0.12 keV in the 1995 observation. If we fit the Fe lines with a blend of two Gaussians centered at 6.39 and 6.73 keV, the intensity of the 6.7 keV line decreases, while the intensity of the 6.4 keV line increases, within an interval of 3.5 yr. This variability rules out thermal plasmas in the host galaxy as the origin of the ionized Fe line in this LLAGN. The detection and variability of the 6.4 keV line indicates that cold matter subtends a large solid angle viewed from the nucleus and that it is located within approximately 1 pc from the nucleus. It could be identified with an optically thick standard accretion disk. If this is the case, a standard accretion disk is present at the Eddington ratio of Lbol/LEdd approximately 2x10-3. A broad disk-line profile is not clearly seen, and the structure of the innermost part of accretion disk remains unclear.

Journal Article↗
PubMed2000

[Treatment of 522 patients with sudden deafness performed oxygenation at high pressure].

INTRODUCTION: Oxygenation at high pressure (OHP) is thought to be useful, even though regional blood flow is decreased, because increasing dissolved oxygen prevents the death of nerve tissue. In this report, we retrospectively investigated the effect of OHP on sudden deafness. OBJECT AND METHOD: We reviewed 522 patients treated with OHP at Kagawa Rosai Hospital over a ten-year period (January 1989 to December 1998). We discussed some prognostic factors: comparison between cases which had been treated with OHP previously and those which had not, number of days between onset and beginning of the treatment which included OHP, age, initial averaged five-frequency hearing level, vertigo, tinnitus, complications of OHP, cases of relapse and the time of the onset, which is about season, month and week. OHP was administered at a pressure of 2.5 atmospheres for 80 minutes a day from 10 to 15 times. All patients also received a course of intravenous administration of steroid, vitamin B12, Prostaglandin E1, ATP, and low-molecular dextran. RESULTS: Overall, complete recovery occurred in 19.7% of the patients, definite improvement in 34.9% (complete recovery included), and slight improvement in 58.1% (definite improvement included). Most of the patients (78.0%) were referred by other hospitals, because our hospital was the only one in the Sikoku area which had a big equipment of OHP. All 161 patients had already been treated in other hospitals over 8 days, but they had shown little improvement after the initial therapy. Of this group, complete recovery after the second course of treatment occurred in 13.0% of the patients, definite improvement in 19.3%, and slight improvement in 39.1%. OHP was thus effective for about 40% of patients who had been unresponsive to the initial therapy. Delay in treatment usually produces poor hearing recovery. There was a significant difference between those patients treated within 14 days and those treated 15 days or more after onset. The improvement rate also decreased with age. The prognosis of patients with vertigo was worse than those without vertigo. Tinnitus had no influence on the prognosis. There were no severe complications during the course of OHP, but otitis media with effusion occurred in 90 patients, and paracentesis was performed for 53 patients. CONCLUSION: The treatment of sudden deafness with OHP has been discussed in this report. Important prognostic factors were time between onset and beginning of the treatment which included OHP, age, vertigo, and the initial averaged five-frequency hearing level. We conclude that OHP should be performed within 14 days from onset, and that OHP was able to achieve hearing improvement in many cases unresponsive to the initial therapy if it was performed very early.

Adolescent↗
PubMed1999

Interaction of PKN with a neuron-specific basic helix-loop-helix transcription factor, NDRF/NeuroD2.

By the yeast two-hybrid screening of a human brain cDNA library with the amino-terminal regulatory region of PKN as a bait, a clone encoding a neuron-specific basic Helix-Loop-Helix (bHLH) transcription factor, NDRF/NeuroD2 was isolated. NDRF/NeuroD2 was co-precipitated with PKN from the lysate of COS-7 cells transfected with both expression constructs for NDRF/NeuroD2 and PKN. In vitro binding studies using the deletion mutants of NDRF/NeuroD2 synthesized in a rabbit reticulocyte lysate indicated that the internal region containing the bHLH domain of NDRF/NeuroD2 was necessary and sufficient for the interaction with PKN. In addition, recombinant NDRF/NeuroD2 purified from Escherichia coli could bind PKN, suggesting the direct interaction between NDRF/NeuroD2 and PKN. Transient transfection assays using P19 cells revealed that expression of NDRF/NeuroD2 increased the transactivation of the rat insulin promoter element 3 (RIPE3) enhancer up to approximately 12-fold and that co-expression of catalytically active form of PKN, but not kinase-deficient derivative, resulted in a further threefold increase of NDRF/NeuroD2-mediated transcription. These findings suggest that PKN may contribute to transcriptional responses through the post-translational modification of the NDRF/NeuroD2-dependent transcriptional machinery.

Animals↗
PubMed1999

Non-linear analysis of the sleep EEG.

A sleep electroencephalogram was analyzed by non-linear analysis. The polysomnography of a healthy male subject was analyzed and the correlation dimensions calculated. The correlation dimensions decreased from the 'awake' stage to sleep stages 1-3 and increased during rapid eye movement (REM) sleep. These results were seen during each sleep cycle. In each sleep cycle, the correlation dimensions decrease for slow wave sleep, and increase for REM sleep.

Adult↗
PubMed1998

Effect of flunitrazepam on sleep and memory.

Flunitrazepam's (FNZ) effect on sleep and memory 1 mg and 2 mg was investigated in 6 healthy volunteers (mean age 21.5 +/- 0.8 years) by polysomnography (PSG) and memory testing. A PSG was recorded on each study night. Memory testing was done before sleep (40 min after taking FNZ or placebo), and after waking (560 min after medication). Rapid eye movement (REM) latency was found to be prolonged on the FNZ 2 mg night (FNZ2N) compared to the baseline night (BN). Percentage of stage 2 sleep was increased in the FNZ2N as compared to BN, while REM percentage on both FNZ nights did not significantly differ from BN. The number of total REM and REM density were decreased in the FNZ2N compared to BN. Memory testing showed significant differences between before sleep and after waking on the FNZ2N. There was a significant correlation between the degree of impairment on memory testing and the rate of reduced REM density, but there was no significant correlation between degree of impairment on memory testing and the rate of increased non-REM sleep on the FNZ2N. The results of this study suggest that impairments in memory result from the dose of FNZ, and that there is a possibility of a relationship between memory disturbance and REM sleep suppression caused by this benzodiazepine.

Adult↗
PubMed1998

Alcohol effect on sleep electroencephalography by fast Fourier transformation.

The influence of alcohol (ethanol) on sleep was investigated in 10 men. Polysomnography (PS) was recorded on a baseline night (BL-N) and an ethanol (0.8 g/kg) night (Et-N). On visual score rapid eye movement (REM) sleep was reduced, REM latency was prolonged on Et-N as compared to BL-N. Using the fast Fourier transformation method, electroencephalographic power density of REM sleep in delta frequencies band and in the 10-12 Hz range of non-REM sleep were enhanced. REM sleep and non-REM sleep changes were prominent in the second-half and first-half of the night, respectively.

Adult↗
PubMed1998

Scar tissue distribution on palates and its relation to maxillary dental arch form.

OBJECTIVE: This study investigated the relationship between maxillary dental arch form and distribution of postsurgical scar tissue on previously denuded bone in isolated cleft palate patients. METHOD: The palatal blood flow of 21 Japanese isolated cleft palate patients (6 males, 15 females) was examined by laser doppler flowmetry to determine the scar tissue areas. All had undergone pushback operations for palatal repair at around 18 months of age. Tissue blood flow was examined at a time ranging from 11 years, 5 months to 19 years, 9 months of age. To evaluate the maxillary dental arch form, dental casts obtained at the start of orthodontic treatment (a mean age of 8 years, 4 months) were analyzed. RESULTS/CONCLUSIONS: Scar tissue distribution in the 21 cases was classified into five types. Characteristic features in the maxillary dental arch form were found in each of the five types according to the extent of the scar tissue. It was evident that the severity of the maxillary dental arch constriction was closely related to the scar tissue distribution on palates.

Adolescent↗
PubMed1998

[Limited operation for stage I lung cancer: a retrospective study].

Although lobectomy is standard therapy for Stage I non-small cell lung cancer, it often cannot be performed in poor-risk patients. In this report, we describe the results of a retrospective study to assess the usefulness of limited operation for stage I lung cancer. Over a 21-year period, 1,286 lung cancers were resected at our center. Among the 497 patients with stage I lung cancer, 36 sublobar resections were performed. There was only one surgery-related death, and the 5-year survival rate was 46% for all patients. At 5 years, survival was 69.2% for patients with squamous cell carcinoma and 33.7% for patients with adenocarcinoma. Survival rates were higher in patients who underwent mediastinoscopy than those who did not, and depended on histological findings and accurate pathological staging.

Adenocarcinoma↗
PubMed1997

Nocturnal melatonin profiles before and one year after beginning shift-work.

Nocturnal serum melatonin profiles were determined twice for seven single women, during their time of employment as nurses (baseline), and after one year (follow up), in order to investigate the effects of shift-work on nocturnal melatonin secretion. All subjects were working in the same hospital under an irregularly rotating three-shift system. Five (5) mL blood samples were drawn six times at 2 h intervals between 20:00-06:00 hours under dim light conditions (< 50 lux). The same sampling procedures were repeated the following year. The results showed pronounced inter-individual differences in melatonin concentrations. There was a trend towards increasing maximum melatonin concentration (MAX melatonin) at follow up, with a similar tendency seen in summed melatonin (the sum of six measured melatonin concentrations). A trend was also seen towards increasing melatonin ratio at 06:00 hours (the percentage of melatonin concentration at 06:00 hours by summed melatonin) at follow up. Melatonin concentration at 06:00 hours was significantly higher at follow up, and a significant correlation between Morningness-Eveningness score (M-E score) at baseline and increased summed melatonin at follow up was also seen. These results suggest that: nocturnal melatonin secretion does not significantly increase after beginning shift-work; and that greater increases in melatonin secretion at follow up are found in subjects with higher M-E scones (increased morning type). With more subjects, however, there may be significant increase in MAX melatonin and/or summed melatonin in the follow-up study.

Adult↗
PubMed1995

[A case of acute eosinophilic pneumonia: bronchoalveolar lavage findings before and after steroid treatment].

An 18-year-old woman presented with coughing, fever, progressive dyspnea, and diffuse infiltrates on the chest X-ray film. Analysis of bronchoalveolar lavage fluid showed 73% eosinophils. Acute eosinophilic pneumonia was diagnosed. Methylprenisolone, 1 g per day was given for three days and her condition improved dramatically. No relapse was observed. Analysis of bronchoalveolar lavage fluid also showed lymphocytosis, abnormally high concentrations of ECP, GM-CSF, IL-5 and sICAM-1, and hypersegmentation of eosinophil nuclei. After steroid treatment almost all these findings returned to normal; only lymphocytosis remained. Precipitating antibodies against four kinds of fungi, including Trichoderma viridae, were noted in the serum, but the environmental provocation test was negative and those fungi were not detected in the environmental culture growth. Comparison of bronchoalveolar lavage findings obtained before and after steroid treatment can provide information on the mechanism of eosinophil accumulation in the lung. This case also draws attention to the relationship between acute and chronic eosinophilic pneumonia.

Acute Disease↗
PubMed1991

[A rare case of allergic granulomatous angitis (Churg Strauss syndrome) with positive anti-glomerular basement membrane (GBM) antibody in serum].

A 33-year-old man with a 6-month history of rhinitis and bronchial asthma was referred to our hospital with polyarthralgia, severe anemia, hypoxemia, mononeuropathy multiplex, and renal insufficiency with hematuria. Marked eosinophilia was observed in his sputum, peripheral blood, and bronchoalveolar lavage fluid (BALF). In addition, his sputum contained many hemosiderin-laden macrophages, indicative of pulmonary hemorrhage. His chest roentgenogram on admission showed diffuse ground grass appearance. High resolution computed tomography (HRCT) demonstrated diffuse high density areas throughout the lung fields and characteristic irregularity and enlargement of the peripheral pulmonary arteries. His general condition rapidly deteriorated, but dramatically improved with oral steroid administration, and his major symptoms disappeared within a few days. Examination of the biopsied lung tissue revealed unequivocal evidence of pulmonary angitis with marked eosinophilic infiltration and perivascular granulomas. Bone marrow biopsy showed hyperplasia of eosinophilic leukocytes in contrast to the low cellularity. Suppression of erythroid hemopoiesis was thought to be the primary cause for his rapidly progressive anemia. Serum anti-GBM antibody titer returned to within the normal range soon after the initiation of steroid therapy.

Adult↗
PubMed1991

[Endobronchial osteochondroma--report of a case].

Endobronchial osteochondroma, a rare neoplasm of the tracheobronchial tree, was treated successfully by surgery in our hospital. A 70-year-old male was admitted with obstructive pneumonia. Bronchoscopy showed an intrabronchial tumor almost completely occluding the orifice of the right B(8+9+10). Biopsy of the tumor did not lead to a specific diagnosis. Right lower lobectomy was performed. The tumor was 1.5 x 1.0 x 1.4 cm in size. The histological diagnosis was osteochondroma. The postoperative course was uneventful, and he is in good condition 19 months after surgery.

Aged↗
PubMed1984

Tumor-forming acute myeloid leukemia with facial paralysis.

A 55-year-old male with acute myeloid leukemia, which had been well controlled for 2 years, developed a sudden onset of facial palsy. Otologic examinations proved the right mastoid bone to be infiltrated by leukemic cells, which formed a nonchloroma to occlude the right external auditory canal. The precise site for the right facial paralysis by tumor formation was found in the intrastapedial region of peripheral portion of the right facial nerve. Regarding the tumor formation in myeloid leukemia, its frequency (particularly among Japanese subjects), complications (particularly in otologic field), possible pathogeneses, and treatments were discussed.

Audiometry↗