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Biomedical subjects

S Aoki

Publications and source records attributed to S Aoki.

At least 469 records · Page 26Linked to original sources
PubMed1989

Doppler color flow mapping of an invasive mole.

We report here Doppler color flow mapping carried out before and after chemotherapy for an invasive mole. This mapping revealed an abnormal color blood flow within the echo-free space in the uterine myometrium, and pulsed Doppler ultrasound showed a prominent arteriovenous shunt flow. Similar features were obtained by pelvic angiography (PAG). After 4 courses of chemotherapy, the area of abnormal colored flow was reduced and findings on the PAG were supportive. The patient is being closely followed, using Doppler color flow mapping.

Adult↗
PubMed1989

Umbilical artery blood flow velocity waveforms and associations with fetal abnormality.

Blood flow velocity waveforms from the umbilical artery of 126 normal fetuses with no evident complications at 20-42 weeks of gestation and 15 fetuses with various abnormalities at 25-42 weeks were recorded using pulsed Doppler ultrasound. The resistance index (RI) was assessed on each blood flow velocity waveform. In 9 fetuses with a slight abnormality, the values of RI were within the mean +/- 2 SD of normal fetuses, and the outcome was good. In 3 of 6 fetuses with a serious abnormality, the values of the RI were high, and 2 of these fetuses died in utero within a few days after the recording. Another fetus with a high RI and 3 with a normal RI died neonatally. Therefore, Doppler ultrasound assessments of the umbilical artery blood flow velocity waveform in utero aid in predicting the outcome for fetuses with major abnormalities.

Blood Flow Velocity↗
PubMed1989

Transvaginal Doppler color flow mapping.

Transvaginal Doppler color flow mapping was performed on 8 Japanese women (normal, 1; menopause, 2; uterine myoma, 1; endometriosis, 2; pregnant, 2). In all 8, bilateral uterine arteries and branches could be clearly identified in shades of blue and/or red. The color flows were abundant in the pregnant women. Transvaginal Doppler color flow mapping is expected to be an important diagnostic tool for assessing uterine arterial blood flows in physiologic and pathologic conditions of the pelvis.

Endometriosis↗
PubMed1989

Effect of dose, pH, and osmolarity on nasal absorption of secretin in rats. III. In vitro membrane permeation test and determination of apparent partition coefficient of secretion.

Nasal absorption of secretin in rats was enhanced in an acid solution and the maximum absorption was observed at a sodium chloride solution molarity of 0.462. In order to predict how changes in the secretin molecule would affect its absorption through the nasal mucosa independently of structural changes in the epithelial membrane, an artificial membrane permeation test was conducted, and the apparent partition coefficient between octanol and a test solution was determined. The concentration of secretin was measured using high performance liquid chromatography. The amount of secretin that permeated through an artificial membrane was hardly affected by changes in pH, which suggest that the size of the secretin molecule was not changed. The apparent partition coefficient, however, increased as the pH of the test solution rose from 3.81 to 7.0, which suggested that the hydrophobicity of secretin was enhanced. In relation to the osmolarity of the test solution, the amount of permeation was hardly affected by the concentration of sodium chloride, but the partition coefficient increased with the concentration of the sodium chloride solution. It was supposed that the size of the secretin molecule was not changed in spite of the increasing hydrophobicity, and the nasal absorption of secretin at a sodium chloride molarity of 0.462 was dependent on a change in the epithelial cells. When sorbitol was used as an osmoregulatory agent, the apparent partition coefficient hardly varied as the osmolarity of the solution was increased, whereas the amount of permeation decreased, and these findings reflected the nasal absorption in rats.

Absorption↗
PubMed1989

Inhibition of PAF-induced eosinophil accumulation in pulmonary airways of guinea pigs by anti-asthma drugs.

Intraperitoneal (i.p.) injection of platelet activating factor (PAF) in guinea pigs caused a dose-related increase in the number of eosinophils recovered from bronchoalveolar lavage fluid (BALF). The prevalence of eosinophils in BALF had significantly increased within 1 hr of i.p. injection of PAF (10 micrograms/animal) and was maximal after 24 hr. Subcutaneous osmotic mini-pumps were used to administer drugs for 5 days prior to i.p. injection of PAF (10 micrograms/animal) and for the subsequent 24 hr. The percentage increase of eosinophils in BALF, due to PAF, was inhibited in animals treated with dexamethasone, aminophylline, cromoglycate, tranilast or ketotifen, but not in animals treated with oxatomide, azelastine, amlexanox, ibudilast or AA-861. These results suggest that inhibition of pulmonary eosinophilia may be a necessary property of prophylactic anti-asthma drugs and provide indirect evidence favoring a role for PAF in eosinophilia of asthma.

Animals↗
PubMed1989

Effects of ryanodine and 9,21-didehydroryanodine on caffeine-induced contraction of rat and guinea pig aortae.

We compared the effects of ryanodine and 9,21-didehydroryanodine (DH-ryanodine), which are present in commercial preparations of 'ryanodine', on the contractions of rat and guinea pig aortae induced by 20 mM caffeine and tested the dependence of the action of each substance on external Ca2+. With the first protocol, the aortae were incubated with ryanodine or DH-ryanodine for 20 min in Ca2(+)-containing medium, and caffeine was added at 2 min incubation in Ca2(+)-free medium. With the second protocol, each substance was added when the external medium was changed to Ca2(+)-free medium, and 20 min later, caffeine was applied. Ryanodine and DH-ryanodine inhibited the caffeine-induced contractions in a similar way; i.e., with maximal effects at 3 microM and lesser effects at 10 microM. The potencies of inhibition by both substances were similar except that the effect of ryanodine at 1.5 microM was more potent than that of DH-ryanodine with the second protocol. The response by muscles previously loaded with Ca2+ to a second application of caffeine was more greatly inhibited by both compounds (use-dependent effect). The inhibition of the contraction due to the first or second application of caffeine was greater when either agent was applied in Ca2+-containing medium than in Ca2(+)-free medium. These results indicate that ryanodine and DH-ryanodine are similar in their effects on caffeine-induced Ca2+ release in vascular smooth muscle and that cellular Ca2+ levels may affect the action of ryanodine.

Alkaloids↗
PubMed1989

[Effects of noise on sleep. Part 1. Development of an automatic analysing system for all-night sleep polygraphy by microcomputer].

In order to assess the effects of noise on sleep, the authors have developed a microcomputer system which determines the sleep stage based on an all-night EEG (electroencephalogram), rapid eye movement and an EMG (electromyogram). All the polygraphic parameters for each epoch (including spindle, rapid eye movement, alpha and delta waves, and amount of muscle tension), which are necessary to determine the sleep stage, were determined by a microcomputer using a digital data processing program. Recognition of EEG waves is based on Fujimori's method with some modifications. The rules of Rechtschaffen et al. were adopted for judging sleep stage with a slight modification. Data were obtained from six healthy students of a university. Each student was polygraphed for five to six nights under various conditions of noise exposure. Judgements of the sleep stage were made by two medical doctors. Using randomly selected 10 nights' data, the agreement between judgements by the microcomputer system and by the doctor was 77%. The percentage of agreement increased to 84% for the epochs in which the two doctors agreed. It takes about one hour to determine all-night sleep stages by this system.

Adult↗
PubMed1989

[Effects of noise on sleep. Part 2. A case report of the effects of three levels of stationary sound on sleep parameters].

The effect of steady noise on sleep was examined experimentally for 24 nights by sleep polygraphy of a twenty-eight-year-old man. The parameters used for sleep polygraphy were sleep stage, sleep latency, frequency of sleep stage shift per hour, average sleep depth, the gradient and intercept of a regression line of sleep depth against time, and subjective sleep. The sleep stage was judged and estimated based on the criteria of Rechtschaffen & Kales by the authors' original system using a microcomputer. For the calculation of sleep depth at a given time, stages W (waking), 1, REM, 2, 3 and 4 were weighted to be 0, 1, 1.5, 2, 3 and 4, respectively. Sleep parameters were compared between the data of non-noise and noise-exposed nights. The noise exposure was overnight stationary pink noise of 40, 50 and 60 dB (A). General findings were a decreased REM stage, an increased stage 2, and deepened average sleep depth of the 60 dB (A)-night sleep compared with the control and 40 dB(A) exposure nights. When the control nights were excluded and parameters were compared between the three levels of stationary noise exposure, stage 2, the intercept of the regression line, and average sleep depth were increased almost in proportion to the increased noise exposure. In contrast, sleep latency, frequencies of sleep stage shift, stages W, 1, 3, MT, and REM, as well as the gradient of the regression line were decreased with increased noise exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Effects of noise on sleep. Part 3. A case report of the effects of three levels of intermittent sound on sleep parameters].

One healthy twenty-eight-year old man was exposed all night to intermittent, rectangular pink noise of 5 and 10 seconds' duration 9 times per hour. The peak levels prepared were 40, 50 and 60 dB(A). One level of the noise was exposed throughout a single night. Ten non-exposed control nights were also prepared. The sleep electroencephalogram was analysed by a microcomputer system of the authors' devising. Increases of sleep latency and stage W, and decreases of the REM stage and mean sleep depth, especially in the early sleep hours, were confirmed in the sleep polygraph of the 60 dB(A) exposure but not in that of the control, 40, and 50 dB(A) exposures. It was concluded from these results that the intermittent 60 dB(A) pink noise exposure clearly disturbed sleep, and that the threshold of the effect should exist between 50 and 60 dB(A) exposure.

Adult↗
PubMed1989

[Baseline study of sleep electroencephalography--daily variation and individual variation].

The aims of the present study were to observe the daily habituation to night sleep in a laboratory environment and to make clear the daily and individual sleep variations by using polygraph parameters, including electroencephalography (EEG). Sleep EEG records were obtained from a subject who slept ten successive nights, and from six subjects who each slept one night in the laboratory. The parameters used were as follows: sleep stage %, sleep latency (SL), REM latency (RL), number of stage shifts, subjective sleep, integral EMG, and slope (a) and intersect (b) of a regression equation used to estimate the sleep depth against sleep time. Stage WAKE and SL, slope (a), intersect (b) and the mean depth of sleep were found to become stable from the fifth night. Stage MT, the number of stage shifts, and integral EMG increased significantly from the fifth night and later, showing p less than 0.01, p less than 0.01, and p less than 0.05, respectively. Judging from these findings, the sleep habituation of the subject in the laboratory was completed within the first four nights. Coefficients of variation of sleep stage 2 and stage REM of the ten-nights' EEG were the lowest among all the sleep parameters examined. Almost all the parameters of day-to-day sleep of the subject who slept for ten successive nights in the laboratory showed smaller variations than those of the other six subjects. It may be concluded that the mist effect on sleep could be assessed more precisely by using an individual repeatedly than by using a group of subjects.

Adult↗
PubMed1989

Fetal cardiac time intervals determined by Doppler echocardiography.

One-hundred and eleven Doppler echocardiographic examinations were performed on 88 normal fetuses, ranging from 16 to 41 weeks of gestation. Aortic and pulmonary maximal velocity (MV), acceleration time (AT), ejection time (ET), MV/AT (acceleration velocity: AV) and AT/ET ratio in systole were assessed on each blood flow velocity waveform. Aortic MV and pulmonary MV correlated well with gestational age, respectively. Good correlations between aortic AT, pulmonary AT and gestational age were evident. There were correlations between aortic AT/ET ratio, pulmonary AT/ET ratio and gestational age, respectively. However, there was no correlation between aortic AV, aortic ET, pulmonary AV, pulmonary ET and gestational age, respectively. These findings may relate to alterations in pulmonary and placental vascular resistance with advance in gestation.

Echocardiography, Doppler↗
PubMed1989

[A case of nasopharyngeal amyloidosis].

A case of amyloidosis localized in the nasopharynx was reported. The patient was a 62-year-old female who complained of persistent nasal obstruction. The gross appearance of this tumor showed a thumb-sized red-yellowish mass, in part covered with white coating. The systemic amyloidosis was excluded by several clinical examinations including rectal biopsy. Histopathological examination revealed diffuse deposits of homogeneous eosinophilic substances. A polarized microscopic examination by congo-red stain showed that deposit's substances were amyloid. A typical amyloid fibril was observed under electron microscope. The mass was removed with Beckmann adenotome. Bleeding was minimal.

Amyloidosis↗
PubMed1989

Doppler ultrasound assessment of tumor vascularity in gynecologic disorders.

Real-time two-dimensional and pulsed-wave Doppler ultrasonic examinations were performed on 8 normal volunteers and 97 patients with various gynecologic disorders; the objective was to assess uterine and tumor vascularities. Each arterial blood flow velocity wave-form was classified into two types. The resistance indices of normal and abnormal flows were greater than .7 and less than .7, respectively. In normal volunteers, abnormal flows were nil. In 8 of 44 patients with benign tumors (18.2%), abnormal flows were evident and all proved to be cases of leiomyoma or adenomyosis. Doppler signals were not detected in 18 of 36 patients with cervical carcinoma (50%) and abnormal flows were noted in only 6 (16.7%). In all cases of endometrial carcinoma, ovarian carcinoma, and trophoblastic disease, typically abnormal flows were noted. Moreover, in most subjects a decrease in blood flows was observed after chemotherapy by anticancer drugs or irradiation. Therefore, Doppler ultrasound is a pertinent and noninvasive tool that can be used repeatedly for assessing the tumor vascularity in gynecologic disorders.

Adult↗
PubMed1989

[A case of advanced uterine cervical cancer responsive to continuous intra-arterial chemotherapy using an implanted drug delivery system].

Selective intra arterial hypertensive infusion of CDDP (100 mg) and PEP (40 mg) with angiotensin II was performed in a 64 year-old housewife with inoperable uterine cervical cancer stage IVa and transitional cell cancer of bladder (grade 1-2). PEP at 5 mg/day was also administered for 20 days (total 100 mg) using an implanted Drug Delivery System through the left internal iliac artery combined with irradiation therapy. There were hardly any side effects due to this treatment except for a slight upper digestive tract disturbance and bone marrow suppression, and the cancerous lesion gradually regressed following this treatment. This case suggested the efficacy of intra-arterial infusion using an implanted Drug Delivery System for advanced uterine cervical cancer. There has been no sign of recurrence six months after this treatment.

Angiotensin II↗
PubMed1989

[Laboratory and clinical studies of clarithromycin in pediatric fields].

We have carried out laboratory and clinical studies on clarithromycin (TE-031, A-56268). The results are summarized as follows. Serum and urinary concentrations of TE-031 were determined in 5 children with ages between 6 and 11 years given single oral doses of 5, 6.7, 10 and 15 mg/kg. Serum concentrations peaked at 1 hour after administration of 5, 6.7 and 15 mg/kg, and respective peak values were 1.98 micrograms/ml, 2.21 micrograms/ml and 5.58 micrograms/ml. Biological half-lives for the drug at 5, 6.7 and 15 mg/kg dose were 2.99 hours, 2.08 hours and 2.09 hours, respectively. Mean serum concentrations peaked at 2 hours after administration of 10 mg/kg, and peak values were 3.91 +/- 1.64 micrograms/ml. Biological half-lives were 3.00 +/- 0.58 hours. The 6-hour urinary recovery rates ranged from 22.7% to 23.8% after administration of 10 mg/kg, and the 6-hour urinary recoveries were 30.1%, 20.5% and 39.1% after administration of 5 mg/kg, 6.7 mg/kg and 15 mg/kg, respectively. Therapeutic responses were recorded as excellent or good in 35(89.7%) of the children, comprising 5 with tonsillitis, 3 with pharyngitis, 7 with bronchitis, 5 with pneumonia, 15 with Mycoplasma pneumonia, 1 with whooping cough and 3 with Campylobacter enteritis. The microbiological effectiveness of TE-031 on identified pathogens comprising 2 strains of Streptococcus pneumoniae, 5 strains of Haemophilus influenzae, 2 strains of Haemophilus parainfluenzae, 5 strains of Mycoplasma pneumoniae and Campylobacter spp. was satisfactory as evidenced by an eradication rate of 82.4%. No significant side effect due to the drug was observed in any cases. In conclusion, TE-031 was found to be efficacious and safe for the treatment of bacterial infections in children.

Age Factors↗