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S Ono

Publications and source records attributed to S Ono.

At least 559 records · Page 31Linked to original sources
PubMed1989

Increased accumulation of N-isopropyl-p-(123I)-iodoamphetamine in two cases with mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes (MELAS).

We present two cases with mitochondrial encephalopathy with lactic acidosis and strokelike episodes (MELAS), which showed both increased and decreased accumulation of N-isopropyl-p-(123I)-iodoamphetamine (123I-IMP) in single photon emission computed tomography (SPECT). The increased accumulation of the tracer occurred, before low density appeared on conventional computed tomography, suggesting that 123I-IMP SPECT may be useful in pathophysiological study of MELAS.

Acidosis, Lactic↗
PubMed1989

Intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies in myotonic dystrophy: a quantitative morphological study.

Intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies have been studied in four patients with myotonic dystrophy (MyD), eight patients with other neurological diseases (control A), and eight patients without neurological diseases (control B). The percentages of the affected cells were calculated by dividing the number of neurons including intracytoplasmic inclusion bodies of the thalamus and the substantia nigra, and Marinesco bodies, by the total cell count in these respective regions. Statistical analyses were performed with regard to the frequency of these bodies by using Student's t test. There was a significantly higher incidence of intracytoplasmic inclusion bodies of the thalamus (13.2% versus 0.7%, P less than 0.001) and the substantia nigra (20.4% versus 2.7%, P less than 0.001), and Marinesco bodies (37.4% versus 4.1%, P less than 0.001) in patients with MyD than in controls A and B. From our observations, it is suggested that the presence with a high frequency, in combination, of these bodies is not an incidental finding but may have an intimate and important relationship with the pathogenesis of MyD, and may be a conspicuous and diagnostically important feature of MyD.

Adult↗
PubMed1989

Differential diagnosis between amyotrophic lateral sclerosis and spinal muscular atrophy by skin involvement.

Amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA) might be clinical variants caused by the same etiology, or different diseases altogether. We studied the skin in 12 patients with ALS and 7 patients with SMA. The "delayed return phenomenon" (DRP) was observed only in ALS patients. On light microscopy, collagen bundles in ALS dermis were seen to be less numerous, thinner and more loosely woven than in SMA. Electron microscopy revealed that in ALS (1) collagen fibers became thinner as the disease lasted longer, and (2) collagen bundles were separated by much more amorphous material. These findings were not observed in SMA. Our observations show that ALS may be distinguished from SMA by the presence of abnormal dermal collagen. Therefore, we suggest that comparable clinical and pathological skin analysis is the most important diagnostic tool in differentiating between ALS and SMA.

Adult↗
PubMed1989

Amyotrophic lateral sclerosis: electrophoretic study of amorphous material of skin.

We studied skin from patients with amyotrophic lateral sclerosis (ALS) and controls by electron microscopy, and analyzed it by sodium dodecyl sulfate-poly-acrylamide gel electrophoresis (SDS-PAGE) and two-dimensional gel electrophoresis. On electron microscopy, the most conspicuous finding in ALS was a markedly increased amount of amorphous material in the ground substance, which became more marked in proportion to the duration of ALS. SDS-PAGE analysis showed that in ALS patients the staining intensity of a low-molecular weight band (approx. 12.5 kDa, band "g") became more marked with the duration of ALS. Two-dimensional gel electrophoresis revealed that band "g" consisted of a single component with a basic isoelectric point. It is thought that the substance corresponding to band "g" is a major constituent of the amorphous material.

Aged↗
PubMed1989

Lack of a modifying effect by the diuretic drug furosemide on the development of neoplastic lesions in rat two-stage urinary bladder carcinogenesis.

The effect of the diuretic drug furosemide on two-stage urinary bladder carcinogenesis in F344 rats initiated by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) was investigated with regard to possible promoting activity. BBN was administered at 2 doses, 0.01 or 0.05%, in drinking water for 4 wk, and thereafter furosemide was given by gavage 3 times weekly for 32 wk, 250 mg/kg body weight. Furosemide ingestion induced diuresis with an alkaline, hypotonic urine. No significant difference with regard to incidences of bladder lesions were apparent between furosemide and control groups. The present investigation indicated that neither furosemide nor its related polyuria acted as a promoter in two-stage urinary bladder carcinogenesis.

Animals↗
PubMed1989

Cluster formation among small resting B lymphocytes leading to B cell activation.

Intercellular contacts are thought to be a crucial event in various aspects of immune responses. We have recently suggested that the self class II MHC-restricted B-B cell interaction is a prerequisite process in the polyclonal B cell differentiation induced by a novel T cell-derived lymphokine B151-TRF2 or LPS. The results have led us to the possibility that such a class II MHC-restricted B-B cell interaction promotes the formation of B cell clusters responsible for the development of IgM-producing cells upon subsequent stimulation with the polyclonal B cell activator. To examine directly this possibility, the present study has utilized a recently devised ACAS470 work station capable of sorting out desired cells in a tissue culture plate in situ. Clusters and non-clusters were observed after 2 day preculture of murine resting B cells in the absence of the polyclonal B cell activator. Interestingly, B cells in clusters purified by the ACAS470 gave rise to IgM-producing cells when stimulated with B151-TRF2 or LPS for an additional 2 days, whereas non-clustered B cells failed to differentiate. Moreover, such a B cell activation was not observed when the 2 day preculture of the resting B cells was conducted in the presence of anti-class II MHC mAb but not of anti-class I MHC mAb. Thus, the present results support the notion that cluster formation among small resting B cells accompanying the class II MHC-restricted B-B cell interaction makes the B cells responsive to differentiation signals of polyclonal B cell activator.

Animals↗
PubMed1989

Application of the trimethylsilyl trifluoromethanesulfonate deprotecting procedure for the synthesis of porcine peptide YY (PYY).

A 36-residue peptide amide corresponding to the entire amino acid sequence of porcine peptide YY (PYY) was synthesized by assembling eight peptide fragments of established purity, followed by hard acid deprotection with 1M trimethylsilyl trifluoromethanesulfonate in trifluoroacetic acid. beta-Cycloheptylaspartate, Asp(OChp), was employed to minimize the base-catalyzed succinimide formation. When administered to dogs, synthetic PYY was active as natural peptide in its effects on exocrine pancreatic secretion and pancreatic tissue blood flow.

Amino Acid Sequence↗
PubMed1989

Portal blood flow: measurement with MR imaging.

Portal blood flow was measured by means of direct bolus imaging (DBI), a method of measuring flow velocity with magnetic resonance imaging. DBI allows immediate visualization of fluid movement, thereby enabling calculation of a flow velocity from fluid displacement. In a study of 14 healthy male volunteers, portal blood flow was measured with electrocardiographic gating during the 18 seconds subjects could suspend respiration. These measurements showed a close correlation (r = .968) with those obtained by means of Doppler ultrasound (US). Increases in portal blood flow after oral administration of ethanol and glucose were measured with DBI. Glucose caused a statistically greater increase in portal blood flow volume in healthy control subjects than in patients with chronic hepatitis. Blood sugar, on the other hand, showed a significantly greater increase in these patients, possibly reflecting the greater vascular resistance of the liver. DBI is a useful noninvasive method of measuring portal blood flow without the limitations imposed on Doppler US by obesity and intestinal gas.

Blood Flow Velocity↗
PubMed1989

Effects of pH and light exposure on the riboflavin-binding capacity in the rat lens.

To elucidate the binding mode of riboflavin to rat lens protein, we examined the effects of light exposure, different pH (4.0, 7.0 and 9.0) and dialysis on the lenticular riboflavin-binding capacity (LRBC). LRBC increased remarkably by light exposure, irrespective of pH. By dialysis, LRBC of a light-exposed incubation mixture decreased remarkably at pH 9.0, however, at pH 4.0 and 7.0, dialysis did not affect it significantly. Decrease in LRBC in light-exposed dialyzed samples at the higher pH may result from release of dialyzable bound riboflavin from binding protein. These data suggest that the dialyzed bound riboflavin at the higher pH may be responsible for a photosensitization of lens protein.

Animals↗
PubMed1989

Solution synthesis of human neuropeptide Y (hNPY).

Human neuropeptide Y (hNPY) was synthesized in a conventional manner by assembling seven peptide fragments followed by reduction of the Met(O) residue with phenylthiotrimethylsilane and subsequent deprotection with 1 M trimethylsilyl trifluoromethanesulfonate (TMSOTf)-thioanisole in trifluoroacetic acid (TFA). Alternatively, deprotection was performed in a two-step manner; first, treatment with 1 M trimethylsilyl bromide-thioanisole in TFA, and then with 1 M TMSOTf-thioanisole in TFA. After purification by gel-filtration on Sephadex G-25, followed by reversed-phase high-performance liquid chromatography, a highly purified sample of synthetic hNPY was obtained in both cases. When administered in dogs, synthetic hNPY was as active as porcine NPY in terms of the effects on systemic arterial blood pressure, pancreatic blood flow, and superior mesentric artery (SMA) blood flow. Met(O)17-hNPY was found to be as active as the parent sample in these bioassays.

Amino Acid Sequence↗
PubMed1989

Clinical significance of exercise-induced negative U-waves in patients with anterior myocardial infarction.

To elucidate the clinical significance of the exercise-induced negative U-wave (NU) in patients with anterior myocardial infarction, we compared the angiographic and scintigraphic findings in 15 patients with and 20 patients without NU, and obtained the following results: 1) On coronary angiography, all patients in the NU (+) group showed over 90% stenosis or total occlusion of the left anterior descending coronary artery (LAD). In the latter cases moderate to abundant collaterals were visualized on the anterior wall. In contrast, such a tendency was not observed in the NU (-) group. 2) Segments composed of viable myocardium (estimated by preservation of contraction at rest and T1-201 redistribution after exercise) numbered 30 of 45 segments (67%) in the NU (+) group, and 13 of 60 segments (22%) in the NU (-) group. Segments composed of lost myocardium (estimated by loss of contraction at rest and persistent defect in T1-201 uptake) numbered 7 of 45 segments (16%) in the NU (+) group, and 38 of 60 segments (63%) in the NU (-) group. 3) Exercise-induced NU was frequently observed on R-wave preserved leads with ST depression, but was also observed over abnormal Q waves, ST elevation and in isolation in some instances. 4) In 3 patients, preexisting exercise-induced NU was no longer observed and a transient stress-induced T1-201 defect disappeared after successful LAD revascularization. In conclusion, exercise-induced NU on precordial leads in patients with anterior myocardial infarction may be a sign suggesting the presence of jeopardized, but still salvageable, myocardium in the infarcted area.

Aged↗
PubMed1989

Expression forms and characteristics of Carr-Purcell-Meiboom-Gill sequence magnetic resonance images.

We propose two expression forms of Carr-Purcell-Meiboom-Gill (CPMG) sequence magnetic resonance images using the imaging parameters of recovery time (Tr), echo interval (Te), echo number (n) from 1 to N (number of echoes). An echo image can be expressed as a form of CPMG (Tr, Texn) and the other image synthesized by summing consecutive echo images numbered from n1 to n2 (l less than or equal to n1 less than n2 less than or equal to N) as a form of CPMG (Tr, Te x n1-n2). The CPMG (Tr, Te x n) images are weighted by T1, T2 or proton density and show the better morphological representation and contrast resolution of brain tumor lesion. The difference of signal intensities among the tissues is enhanced on the synthesized CPMG (Tr, Te x n1-n2) images with the increased signal-to-noise ratio. The calculated T2 images are also observed. These forms expound the scanning conditions and image characteristics and make easy to be compared with the spin echo images.

Brain Neoplasms↗
PubMed1989

Collapse and reexpansion of lungs increase microvascular permeability in sheep.

The pathogenesis of reexpansion pulmonary edema has not been well studied. We tested the hypothesis that both long term collapse and subsequent reexpansion of the lungs cause reexpansion pulmonary edema by increasing pulmonary microvascular permeability. We investigated lymph dynamics in 15 experiments on collapsed lung and 10 experiments after lung reexpansion in 14 unanesthetized sheep with chronic lymph fistulas. We found that 24-hr left lung collapse increased lymph flow through the caudal mediastinal lymph node from the baseline of 1.71 +/- 0.97 (mean +/- S.D.) g/15 min to 2.01 +/- 0.99 g/15 min, although 2-hr collapse did not affect lymph flow. The L/P ratio did not fall below baseline in either experiment. Pulmonary arterial pressure increased by only about 6 cmH2O both in 2-hr and 24-hr collapse. Reexpansion after 24-hr lung collapse also increased lymph flow from the baseline of 1.64 +/- 0.52 g/15 min to 3.20 +/- 0.79 g/15 min during the first 2 hr after reexpansion. The lymph-to-plasma protein concentration ratio did not fall below the baseline. Reexpansion after 2-hr collapse did not affect these variables. We conclude that both long term lung collapse and subsequent reexpansion lead to reexpansion pulmonary edema by increasing pulmonary microvascular permeability.

Animals↗
PubMed1989

A modified signal intensity equation of Carr-Purcell-Meiboom-Gill pulse sequence for MR imaging.

The signal intensity equation of Carr-Purcell-Meiboom-Gill (CPMG) pulse sequences for magnetic resonance imaging was modified to: S(n) = k.M0.exp (-n.Te/T2) [1-exp (-Tr/T1)] where S(n) is a signal intensity of "n-th" echo; k, constant; M0, initial longitudinal magnetization; n, echo number; Te, echo interval; and Tr, recovery time [Tr = TR-(N-1/2).Te; TR, repetition time; N, number of echoes]. To evaluate the accuracies of T1 and T2 values calculated from this modified equation, a phantom experiment using five tubes filled with 0.5 to 8 mM copper sulfate solutions was performed using a 0.14-T resistive whole-body MR scanner and a spectrometer system. The differences between the image values by this equation and the bulk values by the spectrometer were less than 6.2% (mean +/- S.D., 3.3 +/- 2.1%) in T2 and 15.6% (10.4 +/- 4.9%) in T1 (except 8 mM). By this modification, not only the image T2 value with a high accuracy but the image T1 value can be obtained simultaneously.

Magnetic Resonance Imaging↗
PubMed1989

Regional cerebral blood flow in the persistent vegetative state.

Regional cerebral blood flow (CBF) in eight patients in a persistent vegetative state was measured and compared with that in five healthy volunteers. The patients were classified into three groups: Group 1 (locked-in syndrome) consisted of a single patient, Group 2 (typical vegetative state) of five patients, and Group 3 (prolonged coma) of two patients. CBF was measured early after onset by single photon emission computed tomography with 123I-N-isopropyl-p-iodo-amphetamine and/or 99mTc-hexamethyl-propyleneamine oxime. The regions of interest (ROIs) were the bilateral frontal, temporal, parietal, occipital, and cerebellar areas and basal ganglia. The values obtained in these areas were averaged, and the ratio for each ROI [(the value in the ROI/the mean value) x 100] was calculated. "Hyperfrontal distribution" of CBF was found to be rare in both the normal condition and the vegetative state. Higher CBF values were noted in the left than in the right frontal area in four of the five volunteers but in only four of the eight patients. CBF distribution in the frontal lobe was characteristic for each group: Group 1 showed high CBF bilaterally, although the elevation was statistically significant only on the right side, and Group 3 exhibited significantly low values. In Group 2, CBF was variable but, for the most part, within normal limits. Awareness was closely correlated with frontal lobe function and alteration of CBF in the frontal region.

Adult↗