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H Honda

Publications and source records attributed to H Honda.

At least 343 records · Page 19Linked to original sources
PubMed1991

[Role of MRI in diagnosis of adrenal tumors].

The authors evaluated the ability of magnetic resonance imaging (MRI) at 1.5 T to characterize 33 adrenal masses, using visual analysis and the following quantitative variables: signal intensity ratios of tumor/liver, tumor/muscle, and (tumor--muscle)/(fat--muscle) on T2- and T1-weighted images, and the calculated T2 relaxation time of the adrenal masses. All 15 tumors of less than 3 cm in diameter were visually homogeneous on all pulse sequences, whereas the other 18 tumors of over 3 cm appeared to be inhomogeneous. The signal intensity ratios of tumor/liver and tumor/muscle and the calculated T2 relaxation time were not helpful in distinguishing tumors from one another. The ratios of tumor/fat and (tumor--muscle)/(fat--muscle) were useful in distinguishing pheochromocytoma and myelolipoma from other tumors on T2- and T1-weighted images, respectively. However, differentiation among other adrenal tumors appeared to be difficult. The authors concluded that, although MRI might have considerable potential in characterizing adrenal masses, the use of conventional MRI in such analysis is still quite limited.

Adenoma↗
PubMed1991

Preservation of the C-terminus of dystrophin molecule in the skeletal muscle from Becker muscular dystrophy.

Duchenne muscular dystrophy (DMD) is a fatal X-linked recessive disorder of muscle in children. The DMD gene product, "dystrophin", is absent from DMD, while the allelic disease, Becker muscular dystrophy (BMD), exhibits dystrophin of abnormal size and/or quantity. But we are still uncertain about the scenario that internally deleted (or duplicated) dystrophin in BMD possesses its carboxy (C)-terminal region, and severely truncated dystrophin in DMD does not. Here we use a new monoclonal antibody directed against an peptide in the C-terminal end of the dystrophin molecule to show that the C-terminus is preserved in 30 BMD and 24 control skeletal muscles but not in 21 DMD specimens. This result, taken together with data on deletions of the dystrophin gene, emphasizes both the diagnostic and biological importance of the C-terminal domain which is required for proper function and stability of dystrophin, and substantiates the validity of the reading frame hypothesis for DMD versus BMD deletions on a biochemical level.

Amino Acid Sequence↗
PubMed1991

The time courses of visual mislocalization and of extraretinal eye position signals at the time of vertical saccades.

The time course of perceptual mislocalization at the time of vertical saccades was compared with that reported previously for horizontal saccades. Despite the difference in the oculomotor system involved in generating these saccades with different directions, the time course of the perceptual mislocalization and that of the extraretinal eye position signal estimated on the basis of visual mislocalization were the same between vertical and horizontal saccades. The results are discussed in relation to the outflow theory of subtraction, and it is argued that there is a common neural center for producing extraretinal eye position signals for both vertical and horizontal saccades.

Humans↗
PubMed1991

Analysis of interleukin 6 (IL-6)/IL-6 receptor system using monoclonal anti-IL-6 antibodies.

To investigate the IL-6/IL-6 receptor system, we obtained five murine monoclonal antibodies against human IL-6, which neutralize its biological activity. We classified them into two groups (Type I mAb and Type II mAb) according to the epitopes they recognized. These two types of antibodies showed no difference in the manner in which they neutralized IL-6 activity, but they differed in the way they inhibited the binding of IL-6 to its receptor. While Type I mAb inhibited IL-6 binding to its receptor completely, Type II mAb inhibited only partially, even at a concn of Type II mAb sufficient to neutralize biological activity. Scatchard plot analysis revealed that in the case of the human myeloma cell line, the U266 cell, which showed two-phase binding of IL-6 to its receptor, the high affinity binding disappeared and the affinity of the low affinity binding decreased in the presence of Type II mAb. These results suggest that Type I mAb neutralizes IL-6 activity by the blocking of IL-6 binding to its receptor directly. In contrast, Type II mAb neutralizes IL-6 activity not by direct blocking of IL-6 binding to its receptor, but by modulating the binding affinity of IL-6 to its receptor, that is, inhibiting the formation of high affinity binding in IL-6 receptor system. This also indicates that the formation of high affinity may be necessary to transduce the IL-6 signal.

Antibodies, Monoclonal↗
PubMed1991

Computerized tomography for detection and staging of localized and pathologically defined upper tract urothelial tumors.

Between 1980 and 1989, 94 patients were evaluated for upper tract urothelial tumors. Preoperative computerized tomography (CT) scans and pathology reports were available in 30 patients who also had nephroureterectomy for treatment of transitional cell carcinoma. Retrospective evaluation of these CT scans was done without knowledge of the final pathological status to determine accuracy of tumor detection and staging. Pathological findings were also reviewed and the pathological staging was compared to that of CT. At pathological evaluation the 30 renal units contained 34 grossly visible, distinct papillary tumors: 7 were ureteral and 27 were in the renal pelvis. Of the renal units 8 also contained carcinoma in situ that was not visible on any study. Conventional excretory urograms and/or retrograde or antegrade pyelograms detected 28 (82%) and CT 17 (50%) of the 34 papillary tumors. Excluding suboptimal scans due to early generation machines, inadequate intravenous contrast medium or too widely spaced slices caused CT sensitivity to increase to 15 of 22 (68%). It was not possible to distinguish stages Ta to T2 lesions on any radiological study. CT sensitivity for parenchymal invasion was 75% with a specificity of 43%. CT sensitivity for fat invasion was 67% with a specificity of 44%. We conclude that CT is limited in usefulness for detection and staging of low stage upper tract urothelial tumors. While CT is the best current imaging modality over-all for staging of upper tract urothelial tumors, results obtained in low stage tumors must be viewed with caution particularly when precise preoperative clinical staging is essential, such as before nephron-sparing procedures.

Carcinoma in Situ↗
PubMed1991

Time course of satisfaction of search.

"Satisfaction of search" (SOS) refers to the effect in which a second lesion remains undetected after detection of another lesion on the same radiograph. The objective of this study was to clarify our understanding of SOS by relating it to total time of inspection and time intervals before, between, and after discovery of lesions. Detection accuracy of native lesions in chest radiographs, before and after the addition of a simulated nodular lesion, was measured for ten observers. Analysis of data from this and a previous experiment showed that average perceptual accuracy of individual receiver operating characteristic curves was significantly reduced with the addition of the nodules. Plots and analyses of search time revealed that, on average, during a typical 46-second inspection of a case, simulated nodules were found at 18 seconds, native abnormalities at 25 seconds, and false positives occurred at 33 seconds. Time needed to find nodules did not depend on whether native lesions were present; time to find native lesions did not change with addition of nodules; and total search time was the same for images with one, two, or no lesions. The detection results show that the SOS effect was obtained, but that interrupting search in order to measure it also diminishes accuracy. Analysis of the time course data relates SOS to perceptual capture and strategic halting of search.

Diagnostic Errors↗
PubMed1991

Organization and chromosomal localization of the human platelet-derived endothelial cell growth factor gene.

Human platelet-derived endothelial cell growth factor (hPD-ECGF) is a novel angiogenic factor which stimulates endothelial cell growth in vitro and promotes angiogenesis in vivo. We report here the cloning and sequencing of the gene for hPD-ECGF and its flanking regions. This gene is composed of 10 exons dispersed over a 4.3-kb region. Its promoter lacks a TATA box and a CCAAT box, structures characteristic of eukaryotic promoters. Instead, six copies of potential Sp1-binding sites (GGGCGG or CCGCCC) were clustered just upstream of the transcription start sites. Southern blot analysis using genomic DNAs from several vertebrates suggested that the gene for PD-ECGF is conserved phylogenetically among vertebrates. The gene for hPD-ECGF was localized to chromosome 22 by analysis of a panel of human-rodent somatic cell hybrid lines.

Animals↗
PubMed1991

Transient pulsus alternans induced by isosorbide dinitrate: echocardiographic and hemodynamic evidence of reduced venous return--a case report.

Transient pulsus alternans was induced by isosorbide dinitrate (ISDN) in a patient with postmyocarditis congestive heart failure under diuretic therapy. The severity and duration of pulsus alternans depended on the dose of ISDN. According to the echocardiographic and hemodynamic examinations, the superimposed preload reduction caused by ISDN combined with decreased blood volume owing to diuretic therapy most likely contributed to the development of pulsus alternans.

Adult↗
PubMed1991

Vibration analysis of the human left ventricular posterobasal wall at the moment of the first heart sound emission.

We examined whether human left ventricular (LV) wall vibration at the first heart sound emission (LVvibr) could be a potential source of information about the left ventricular physical properties, as has been demonstrated by experimental forced vibration studies. LV posterobasal wall vibration in 51 subjects characterized by functional murmur (n = 13), mitral stenosis (n = 8), hypertrophic cardiomyopathy (HCM, n = 8), ischemic heart disease with old myocardial infarction (n = 12) and without prior infarction (n = 10), was detected with a miniature intraesophageal vibration sensor. Peak frequency, sharpness and peak power of LVvibr in patients with functional murmur and mitral stenosis were linearly related to the Q-vibration interval. HCM patients showed a higher peak frequency and sharper configuration in the power spectrum. However, differing from previous reports, we found no characteristic difference in configuration of power spectrum in patients with ischemic heart disease. These results suggest that human LVvibr possibly includes information demonstrated by experimental forced vibration analysis.

Adolescent↗
PubMed1991

Bilirubin conjugation and biliary bilirubin excretion after intravenous bilirubin injection in dogs.

This study was undertaken to investigate the bilirubin clearance, bilirubin conjugation and biliary bilirubin excretion after an intravenous single bilirubin injection (5 mg/kg or 10 mg/kg) in 10 mongrel dogs. Serum total bilirubin concentration increased after the bilirubin injection, and then it immediately decreased. Biliary excretion of loaded bilirubin induced a rapid increase of the bile total bilirubin concentration and bilirubin-monoconjugate. In the 10 mg/kg group, the increase was larger than in the 5 mg/kg group and remained high up to 4 hr after injection, whereas in the 5 mg/kg group these bile components tended to decrease and returned to the preinjection levels within 4 hr. The total bile acid concentration in the bile remained unchanged in both groups. The bile flow did not change in the 5 mg/kg group, but in the 10 mg/kg group it decreased after bilirubin loading. Significantly positive correlations were observed between total bilirubin and bilirubin monoconjugate concentrations in bile both before and 1 hr after injection, but the slopes of regression lines were markedly different from each other. These results suggest that a bilirubin load surpassing the conjugating capacity of the hepatocytes increases bile bilirubin monoconjugate and also enhances the conjugating activity in the liver.

Animals↗
PubMed1991

A kinetic analysis of cell disruption by bead mill. The influence of bead loading, bead size and agitator speed.

The influence of operating parameters such as bead loading, peripheral velocity and bead size on the kinetic behavior of cell disruption in a bead mill was investigated. The bead mill was equipped with a single rotating disc and operated batchwise. Analysis of the data showed that the frequency of bead collision may be correlated to the observed first-order process, applying a new concept called effective disruption volume. It was found that the first-order rate constant was proportional to the square of bead loading within the other experimental conditions examined and increased with the decrease in bead diameter. A new disruption kinetics was proposed, explaining all the observed data in terms of the frequency of bead collision and the concept of effective disruption volume. Although other types of microorganisms were not examined, the concept may well be extended to various kinds of cells.

Saccharomyces cerevisiae↗
PubMed1991

Prevention of posttransfusional non-A, non-B hepatitis by a screening test for hepatitis C virus antibody of donor bloods.

The preventive effect on posttransfusional non-A, non-B hepatitis (PTH) of screening out HCV-Ab positive blood and the prevalence of HCV-Ab-positive donor blood were examined. The incidence of HCV-Ab-positivity in donor blood A was 0.9% and that in donor blood B was 1.35%. The mean ALT and guanase levels were 11.5 +/- 5.8 and 0.58 +/- 0.24 IU/l in HCV-Ab negative blood and 17.3 +/- 7.9 and 0.84 +/- 0.23 IU/l in HCV-Ab-positive blood. Both levels were significantly higher in HCV-Ab-positive blood. These differences were considered to be nonspecific, but there may be some relationship between the levels of ALT and guanase in donor blood and the HCV carrier status. After adoption the screening test for HCV-Ab positive blood, there was no case of a definite diagnosis of PTH, although 4 patients (6.6%) suspected of developing PTH. So, the incidence of PTH was clearly lower than the lowest incidence before adoption of this test. Therefore, we conclude that screening for HCV-Ab in donor blood should be routinely used for prevention of PTH.

Blood Donors↗
PubMed1991

Ultrasonographic anatomy of veins draining the left lobe of the liver. Feasibility of live related transplantation.

The anatomic variations of the left hepatic vein (LHV) in 182 patients with normal liver functions were analyzed using ultrasonography in order to clarify the feasibility of live related hepatic transplantation (LRHT). LHV was demonstrated in 151 patients (83%). Based on the location of the confluence of the middle hepatic vein (MHV) and LHV and the ramifications of the left medial vein (LMV) and the left superior vein (LSV), the livers were classified into 3 types: a) intrahepatic confluence (42/151 livers, 27.8%); b) extrahepatic confluence (69/151 livers, 45.7%); c) separate insertion (40/151 livers, 26.5%); and 23 subtypes. The length of the common trunk and the intrahepatic common trunk of MHV and LHV and the distance from LMV or LSV to the confluence of MHV and LHV were measured. Overall, the control of LHV in situ for LRHT appeared easy in 34/151 patients (22.5%), while in 44/151 patients (29.1%), the length of free LHV and the common trunk was less than optimal for procurement of a left hepatic lobe graft with complete venous outflow and sufficient extraparenchymal length of LHV.

Adult↗
PubMed1991

[A family with autosomal dominant hereditary myoedema, muscular irritability, stiffness and hypertrophy].

A familial case with autosomal dominantly transmitted myoedema, muscular irritability, stiffness and hypertrophy was reported. The patient is 54 years old and his father, two sisters and niece had suffered from the similar symptoms. He had noticed a feeling of stiffness and pain in the femoral muscles after several minutes of erect position from the age of 5-6 years. He had observed that light tapping of muscles caused a bulge which persisted for several seconds in the whole body. These symptoms were not progressive. The patients had an athletic appearance, hypertrophy of gastrocnemius muscles, pes cavus and hammer toes. Mild muscular weakness and wasting were noted in the intrinsic hand muscles and the anterior tibial muscles. Myoedema was seen in the muscles of the whole body. His thyroid functions were normal. EMG studies showed no myotonic discharges. Light microscopy of biopsy specimens from the biceps brachii muscle showed unspecific myopathic changes. Electron microscopy showed many vacuoles between myofibrils. The symptoms and signs of this case are very like to those of the cases which Torbergsen described in 1975 and only four families were reported after that. The family presented here is the first report in Japan.

Edema↗
PubMed1991

[New method for estimating left ventricular myocardial elasticity by vibration analysis].

We solved numerical solutions of Advani-Lee's equation, which treats free vibrations of fluid-filled spherical shells, and forms the basis for non-invasive estimation of left ventricular myocardial elasticity. Numerical results showed that elasticity is approximated by E = 86.5.a2.f2 (E: elasticity (dyn/cm2), a: internal radius (cm), f: eigen-frequency (Hz)). To examine the accuracy of this theoretical equation in estimating elasticity, we made 7 spherical shells of silicone rubber, and compared the estimated elasticity by this equation with that by a standard stretch test. The elasticity calculated by Advani-Lee's equation and by stretch test proved to be nearly identical. Therefore, we concluded that we can estimate the elasticity of a spherical shell using this equation. We calculated the myocardial elasticity at the first heart sound emission in 25 normal persons with a simplified (approximated form of) Advani-Lee's equation. The mean elasticity in normal subjects was (7.04 +/- 2.46) x 10(5) dyn/cm2.

Elasticity↗
PubMed1991

[Technetium-99m-pyrophosphate myocardial scintigraphy in polymyositis--a case report].

A patient with polymyositis who had cardiac involvement underwent myocardial scan with technetium-99m-pyrophosphate. We used Activity Index for evaluating myocardial uptake of technetium-99m-pyrophosphate, which correlated with the degree of serum creatine phosphokinase elevation. Our findings indicate that these examinations may be helpful for identifying patients who have cardiac involvement and evaluating their response to the treatment with corticosteroids or immunosuppressants.

Cardiomyopathies↗