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Biomedical subjects

H Shono

Publications and source records attributed to H Shono.

At least 37 records · Page 2Linked to original sources
PubMed1997

Mechanisms of limited maximum coronary flow in severe single-vessel coronary artery disease in humans due to vertical steal.

We evaluated the usefulness of a decrease in the average peak velocity from 4 to 10 minutes after infusion of dipyridamole for detecting myocardial ischemia in 50 patients, including patients with a prior myocardial infarction. The decrease in the average peak velocity from 4 to 10 minutes associated with vertical steal and combined with a coronary flow reserve of < 1.6 had a high predictive value for myocardial ischemia in patients with or without prior myocardial infarction.

Aged↗
PubMed1997

A new predictor of restenosis after successful percutaneous transluminal coronary angioplasty in patients with multivessel coronary artery disease.

With the goal of improving prediction of restenosis after percutaneous transluminal coronary angioplasty (PTCA) for multivessel coronary artery disease (CAD), we evaluated the usefulness of serial exercise treadmill tests. We previously reported that an increase in the deltaST/delta heart rate (HR) index at follow-up over the value obtained several days after PTCA was useful for detecting restenosis following PTCA for 1-vessel CAD. In that report, comparison of the deltaST/deltaHR index was made based on measurements from the lead disclosing the greatest ST displacement before PTCA. This method was not applicable to patients with multivessel CAD. Seventy-eight patients with multivessel CAD before and several days after PTCA and just before follow-up performed exercise treadmill tests. Simple HR-adjusted indexes of ST-segment depression during exercise (deltaST/deltaHR index) and the sum of the deltaST/deltaHR index in leads II, III, aVF, V4, V5, and V6 (sigma deltaST/deltaHR index) were determined. We compared the predictive power of an increase in sigma deltaST/deltaHR index at follow-up with that of a positive exercise treadmill test and a positive thallium scintigram for restenosis. At follow-up, 37 of the 78 patients showed restenosis. The sigma deltaST/deltaHR index had increased in 30 of these 37 patients (81%), and in 12 of the 41 patients (29%) without restenosis. An increase in sigma deltaST/deltaHR index had a significantly higher sensitivity than the other methods and a significantly higher specificity than a positive exercise treadmill test.

Aged↗
PubMed1997

The effect of behavioral states on fetal heart rate and middle cerebral artery flow-velocity waveforms in normal full-term fetuses.

OBJECTIVES: To evaluate the effect of fetal behavioral states on the relationship between fetal heart rate (FHR) and middle cerebral artery resistance index (MCA RI) in normal fetuses. METHODS: The FHR and MCA RI of 10 normal cases from 37 to 40 weeks of gestation were recorded consecutively over a 45-min period. Correlations between the MCA RI and FHR during resting and active phases, classified by an actocardiotocogram, were analyzed by simple regression analysis. RESULTS: The mean FHR and MCA RI were significantly higher during the active phase (140.3 +/- 6.6 bpm, 0.79 +/- 0.06) than those during the resting phase (137.4 +/- 6.8 bpm, 0.75 +/- 0.07, P < 0.01, two sample t-test). There was a significant negative correlation (r = - 0.22, n = 2642, P < 0.01) between RI and FHR during the active phase and a significant positive correlation (r = 0.28, n = 2066, P < 0.001) during the resting phase. CONCLUSIONS: The relationship between FHR and the MCA RI during the resting phase is different from during the active phase.

Behavior↗
PubMed1996

Increase in the delta ST/delta heart rate (HR) index: a new predictor of restenosis after successful percutaneous transluminal coronary angioplasty.

With the goal of improving the prediction of restenosis after percutaneous transluminal coronary angioplasty (PTCA), we evaluated the usefulness of the delta ST/delta heart rate (HR) index derived from serial exercise treadmill tests. Exercise treadmill tests were performed by 125 patients with single-vessel coronary artery disease before and several days after PTCA, and just before follow-up angiography 3 to 12 months later. Simple HR-adjusted indexes of ST-segment depression during exercise (delta ST/delta HR index) were derived. We compared the usefulness of the increase in delta ST/delta HR index at follow-up over the value obtained several days after PTCA for prediction of restenosis with that of a positive exercise treadmill test and a positive thallium scintigram at follow-up. At follow-up, 47 of the 125 patients showed restenosis. The delta ST/delta HR index increased in 43 of 47 patients in the restenosis group and in 18 of 78 patients without restenosis (p < 0.0001). Separate analysis of each criterion revealed the following respective values for sensitivity, specificity, and positive and negative predictive values for prediction of restenosis; increased delta ST/delta HR index of follow-up: 91%, 77%, 70%, and 94%; positive exercise treadmill test: 83%, 65%, 59%, and 86%; and positive thallium scintigram: 79%, 78%, 69%, and 86%. The increased delta ST/delta HR index had a significantly (p < 0.05) higher sensitivity than the positive thallium scintigram and a significantly (p < 0.01) higher specificity than the positive exercise treadmill test. An increased delta ST/delta HR index at follow-up identifies subgroups of patients who are at high risk for restenosis after PTCA.

Aged↗
PubMed1996

Diurnal variations in resting-active cycles in full-term fetal heart rate changes.

To elucidate the mechanism of the resting-active cycles (RAC) of fetal heart rates (FHR), in the resting and non-resting phases (RP and NRP), 24-h FHR recordings were made on 16 normal full-term pregnant women. RP, NRP, RAC-1 (NRP-NRP cycle), and RAC-2 (RP-RP cycle) were defined based on the criteria of Nijhuis et al. Frequency distributions were plotted separately for the entire 24-h period as well as for the day-time (07:00-21:00 h) and night-time (21:00-07:00 h), and were compared using Kolmogorov-Smirnov two-sample tests. The mean durations (+/- S.D.) (min) of RP, NRP, RAC-1, and RAC-2 were 22.7 +/- 11.2, 67.3 +/- 47.2, 90.0 +/- 47.6, and 89.9 +/- 48.6 during 24-h periods, 20.1 +/- 7.7, 68.3 +/- 52.3, 88.6 +/- 53.1, and 88.4 +/- 53.0 during the day-time, and 25.4 +/- 13.2, 66.2 +/- 41.2, 91.4 +/- 41.0, and 91.5 +/- 43.4 during the night-time. Length of RP was the only factor significantly different during the day and night (P < 0.05). We propose that there are different mechanisms controlling RP and NRP.

Activity Cycles↗
PubMed1995

Chronological changes in subjective symptoms during pregnancy in nulliparous and multiparous women.

BACKGROUND: To investigate chronological changes of subjective symptoms during a normal pregnancy in nulliparous and multiparous women. METHODS: Prospective data were collected using a 20-item questionnaire (general fatigue, headache, palpitation, nausea/vomiting, fever, insomnia, edema, abnormal abdominal size, urinary frequency, lumbago, fetal descent, genital bleeding, watery discharge, high frequency of uterine contraction, increase in frequency of uterine contraction, strong intensity of uterine contraction, increase in intensity of uterine contraction, no change of uterine contraction at rest, high frequency of fetal movements, strong intensity of fetal movements) at Tsushima Izuhara Hospital in Nagasaki Prefecture, Japan. Seven hundred and twenty-nine nulliparous and 588 multiparous normal pregnant women were questioned from 1988 to 1992. A simple (chi-square test) analysis of appearance percentages in each item for every term of pregnancy was made. RESULTS: Each symptom showed different chronological patterns. In the simple analysis, there were significant differences (p < 0.05) in 10 symptoms (headache, palpitation, fever, insomnia, lumbago, fetal descent, watery discharge, increase in frequency of uterine contraction, strong intensity of uterine contraction, strong intensity of fetal movements) between nulliparous and multiparous subjects. In the multiparous group, there was a higher severity in eight of the ten symptoms, except for fever and watery discharge. CONCLUSIONS: The multiparous group had more complaints than did the nulliparous subjects. These normal patterns are of practical clinical use concerning subjective symptoms of pregnancy.

Chronology as Topic↗
PubMed1994

Neonatal assessment using the Apgar fuzzy expert system.

We applied fuzzy theory to the Apgar scoring system (APG) to devise an Apgar fuzzy expert system (AFES). Three AFESs were determined separately by each one of three doctor groups (four inexperienced obstetricians, four experienced obstetricians and four expert neonatologists) in order to demonstrate that the AFES reflected the examiner's expertise and situation. Two-hundred and sixty-seven neonates were assessed 1 min after birth by an experienced obstetrician using the APG and the three AFESs. Statistical analysis of the relationship between the APG and the three AFESs in the acidosis group showed that the AFES determined by four expert neonatologists had the highest sensitivity and were significantly different (p < 0.05) from the APG. The AFES determined by the four expert neonatologists was revealed to be a valuable tool.

Acidosis↗
PubMed1994

Prognostic implications of novel beta cardiac myosin heavy chain gene mutations that cause familial hypertrophic cardiomyopathy.

Three novel beta cardiac myosin heavy chain (MHC) gene missense mutations, Phe513Cys, Gly716Arg, and Arg719Trp, which cause familial hypertrophic cardiomyopathy (FHC) are described. One mutation in exon 15 (Phe513Cys) does not alter the charge of the encoded amino acid, and affected family members have a near normal life expectancy. The Gly716Arg mutation (exon 19; charge change of +1) causes FHC in three family members, one of whom underwent transplantation for heart failure. The Arg719Trp mutation (exon 19; charge change of -1) was found in four unrelated FHC families with a high incidence of premature death and an average life expectancy in affected individuals of 38 yr. A comparable high frequency of disease-related deaths in four families with the Arg719Trp mutation suggests that this specific gene defect directly accounts for the observed malignant phenotype. Further, the significantly different life expectancies associated with the Arg719Trp vs. Phe513Cys mutation (P < 0.001) support the hypothesis that mutations which alter the charge of the encoded amino acid affect survival more significantly than those that produce a conservative amino acid change.

Adolescent↗
PubMed1994

Fetal heart rate recorder for long-duration use in active full-term pregnant women.

We sought to assess the signal consistency and accuracy of a long-duration fetal heart rate (FHR) recorder (a 1-MHz ultrasonic Doppler transducer composed of six miniprobes and an autocorrelation technique) in active, full-term pregnant women. The FHR data of 15 normal full-term fetuses were obtained every 250 milliseconds in various maternal positions using the new Doppler system or a direct scalp electrocardiographic (ECG) transducer. Differences between simultaneous Doppler and ECG measures were small and within acceptable limits except for short-term variability. Signal loss, assessed in 15 subjects in various positions, was less than 10% except during sitting or walking. The mean (+/- standard deviation) percentages of FHR signals lost over 2 hours in bed, 1 hour out of bed, and 24 hours in and out of bed were 1.2 +/- 2.1, 12.9 +/- 16.2, and 3.8 +/- 4.4, respectively. This system for recording FHR is suitable for clinical research and routine FHR monitoring, and provides data comparable to Holter ECG monitoring in patients with heart disease.

Electrocardiography↗
PubMed1992

Application of fuzzy logic to the Apgar scoring system.

Apgar fuzzy expert system (AFES) applied fuzzy logic to the Apgar Scoring System (APG). We prepared the AFESs for both an inexperienced obstetrician (resident A) and an experienced obstetrician (specialist B) separately. We then compared their evaluations of the same 80 neonates at 1 min after birth using both the AFES and the APG. Analysis of the relationship of the general evaluation by the APG (scores below 6 or over 7) and the AFES (bad or good) to the umbilical arterial blood gases (pH below or above 7.20) showed that the sensitivities were 0.36 for the APG evaluation by resident A, 0.50 for the APG evaluation by specialist B, 0.60 for the AFES rating by resident A, and 0.71 for the AFES rating by specialist B. The specificities were 0.94, 0.95, 0.97 and 0.97, respectively. These results demonstrated that the AFES was capable of reflecting the recognition of the examiner.

Apgar Score↗
PubMed1992

Right ventricular wall motion disturbance and determinants of the appearance of hemodynamic right ventricular infarction.

In order to elucidate the mechanisms of the appearance of hemodynamic right ventricular infarction (RVI), we studied right and left ventriculograms and hemodynamic findings in 52 patients with acute inferior myocardial infarction. Right ventricular wall motion disturbance (RVWMD) was detected in 69% of patient but hemodynamic RVI was observed only in 16%. Among patients with RVWMD, there was no significant difference in right ventricular ejection fraction between those with (group III) and without (group II) hemodynamic RVI, suggesting that right ventricular (RV) systolic dysfunction does not independently produce hemodynamic RVI. Right ventricular end-diastolic volume index was similar in groups II and III in spite of higher mRA in group III. The result suggested that the RV compliance of group III was decreased. Heart rate (HR) was significantly lower in group III than in group II. Not only physiologic pacing but also VVI pacing significantly improved hemodynamics in patients with hemodynamic RVI. A positive correlation between HR and cardiac index was observed (r = 0.56, p < 0.001) in patients with RVWMD. Decreased RV compliance and bradycardia were considered to be determinants of the appearance of hemodynamic RVI. Volume loading did not improve hemodynamics significantly in patients with hemodynamic RVI.

Angiography, Digital Subtraction↗
PubMed1992

[Clinical study on myocardial imaging with beta-methyl-p-(123I)-iodophenyl-pentadecanoic acid in patients with mitochondrial myopathy].

Myocardial imaging with beta-methyl-p-(123I)-iodophenyl-pentadecanoic acid (123I-BMIPP), a new radiopharmaceutical designed to evaluate myocardial fatty acid metabolism, was performed in 7 patients with mitochondrial myopathy to detect their myocardial damages in comparison with 201Tl myocardial imaging. These patients were divided into 4 chronic progressive external ophthalmoplegia (CPEO) cases, 2 mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) cases and 1 myoclonus epilepsy with ragged-red fibers (MERRF). In visual assessment, we observed more myocardial segments with decreased uptake of 123I-BMIPP compared to 201Tl in MELAS cases than in CPEO cases. The mean myocardial uptake of 123I-BMIPP was higher than that of 201Tl in CPEO cases. On the other hand, in MELAS and MERRF cases, the mean myocardial uptake of 123I-BMIPP was lower than that of 201Tl. Abnormal findings suggesting myocardial damages were observed in echocardiogram and/or in electrocardiogram in MELAS and MERRF cases, while no such abnormal findings were observed in CPEO cases. Along with the previously reported experimental result that the impairment of rat myocardial mitochondria decreased myocardial uptake of 125I-BMIPP, these results suggest that 123I-BMIPP may be useful to detect myocardial damages in patients with mitochondrial myopathy.

Adolescent↗
PubMed1991

Ritodrine-induced agranulocytosis.

This is the first reported case of development of agranulocytosis induced by continuous intravenous infusion of a large quantity of ritodrine hydrochloride for tocolysis. It is suspected that the pathophysiological mechanism is a dose-related toxic reaction and a cell loss maturation process of myelocytes.

Adult↗
PubMed1991

Chaos and fractals which 1/f spectrum below 10(-2) Hz demonstrates full-term fetal heart rate changes during active phase.

Human fetal heart rate changes were analysed using power spectral density (PSD). The data for analysis were obtained from 25 normal fetuses between the 37th and 40th week of gestation. Pulse interval distribution showed an almost Gaussian distribution. PSD was calculated by first Fourier transform technique, and showed the particular fluctuation below 10(-2) Hz to be inversely proportional to frequency (so called '1/f spectrum') during the active phase after the 37th week of gestation. These results revealed that the 1/f spectrum of the human heart rate had already appeared below 10(-2) Hz in full term of pregnancy.

Echocardiography↗
PubMed1991

Changes in auditory brainstem responses of normal neonates immediately after birth.

To clarify the functional changes in the acoustic conduction pathway in the human immediately after birth, auditory brainstem responses (ABR) in 58 normal neonates were examined. In longitudinal and cross-sectional analysis, the peak latency of wave 1 showed significant shortening (p less than 0.05) from 1.82 +/- 0.23 ms (mean +/- SD) at 30 min after birth to 1.69 +/- 0.26 ms at 2 h after birth. It continued to decrease gradually therafter. The interpeak latency of waves 1-3 decreased gradually (not significant) from 2.82 +/- 0.19 ms (30 min after birth) to 2.74 +/- 0.15 ms (1 month after birth), while the interpeak latency of waves 3-5 decreased significantly from 2.63 +/- 0.27 ms (30 min after birth) to 2.47 +/- 0.23 ms (24 h after birth; p less than 0.01). These results indicate that functional changes in the acoustic system immediately after birth represent rapid adaptation of the peripheral region to extrauterine environment and development of the more central region.

Evoked Potentials, Auditory, Brain Stem↗