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Biomedical subjects

H Onishi

Publications and source records attributed to H Onishi.

At least 109 records · Page 6Linked to original sources
PubMed1995

The putative actin-binding role of hydrophobic residues Trp546 and Phe547 in chicken gizzard heavy meromyosin.

In the course of myosin-catalyzed ATP hydrolysis, certain amino acid residues in myosin interact with counterparts in actin to produce the relational changes that underlie muscle contraction; some of these interactions are ionic, but the stronger interactions are hydrophobic. In an effort to identify myosin residues participating in hydrophobic interactions, myosin (from smooth muscle) fragments with mutations at suspected sites were engineered and compared with wild-type fragments. It was found that the ATPase of doubly mutated (Trp546Ser and Phe547His) fragments was minimally activated by actin and did not decorate actin well to form the regular arrowhead pattern characteristic of myosin binding to actin filaments. Thus, we suggest that Trp546 and Phe547 are important participants in the hydrophobic actin-myosin interaction.

Actins↗
PubMed1995

Plasma neuropeptide Y is reduced in patients with Alzheimer's disease.

Neuropeptide Y (NPY) is demonstrated to be involved in the pathophysiology of Alzheimer's disease, as well as somatostatin. We measured the plasma NPY content in patients with Alzheimer's disease and healthy control subjects (n = 25) by HPLC coupled with radioimmunoassay. The difference in screening pattern of NPY-like immunoreactivity in 50 fractions eluted by HPLC obtained from the plasma peptide-rich fraction between patients with Alzheimer's disease and healthy controls suggested the abnormal metabolism of plasma NPY in patients with Alzheimer's disease. Plasma NPY in patients with Alzheimer's disease was significantly decreased compared with that in healthy controls, which was compatible with the findings obtained from the brain and cerebrospinal fluid and could be involved in the pathogenesis or pathophysiology of Alzheimer's disease.

Aged↗
PubMed1995

Functional chicken gizzard heavy meromyosin expression in and purification from baculovirus-infected insect cells.

The heavy chain and the essential and the regulatory light chains of chicken gizzard heavy meromyosin (HMM) were coexpressed in Spodoptera frugiperda (fall armyworm) cells infected with a mixture of two recombinant Autographa californica baculoviruses. Soluble HMM consisting of the heavy chain and the two types of light chains was obtained. The recombinant HMM was purified from the virus-infected cells and characterized. The regulatory light chain of the isolated recombinant HMM was phosphorylated by myosin light chain kinase in the presence of calmodulin in a Ca(2+)-dependent manner. The ATPase of the recombinant HMM was activated by rabbit skeletal muscle actin when myosin light chain kinase, calmodulin, and Ca2+ were present in the reaction medium. Chicken gizzard tropomyosin enhanced the actin-activated ATPase activity. The recombinant HMM decorated actin filaments, displaying the characteristic arrowhead pattern along the filaments. This report on a functional recombinant double-headed smooth muscle myosin fragment opens the way to detailed studies on the molecule.

Actins↗
PubMed1995

MvaI polymorphism in the proteolipid protein (PLP) gene.

We report a rare polymorphism in the human proteolipid protein (PLP) gene. A synonymous mutation, 168 A-->G, was detected in exon 2 of the PLP gene. Mutations in this gene have been reported in some cases of Pelizaeus-Merzbacher disease.

Base Sequence↗
PubMed1995

Metabolic profile of opioid peptides differs in the hippocampus and striatum of seizure-susceptible E1 mice.

We previously suggested that a deficit of anticonvulsant endogenous methionine enkephalin, in the cerebral cortex, septal area, hippocampus, and striatum of seizure-susceptible El mice plays a role in the pathogenesis of seizures. To determine whether a hypofunction of enkephalinergic neuron may be due to metabolic abnormalities of opioid peptides in the El mouse brain, we measured methionine enkephalin-like immunoreactivity (ME-LI) of 50 fractions eluted by high performance liquid chromatography obtained from those four regions of the brain of El and seizure-nonsusceptible ddY mice (the mother strain of El mice). We observed the same ME-LI patterns of 50 fractions in the cerebral cortex and septal area in El and ddY mice, whereas exhibited differing ME-LI patterns in the hippocampus and striatum in the two stains. Different ME-LI patterns may imply the difference in the metabolic profile of opioid peptides. Thus, an abnormal metabolism of opioid peptides in the hippocampus and striatum of the El mouse may be involved in the pathogenesis of seizures.

Animals↗
PubMed1995

HPLC/RIA analysis of bioactive methionine enkephalin content in the seizure-susceptible El mouse brain.

We previously reported a deficit of methionine enkephalin-like immunoreactivity (ME-LI), in the cerebral cortex, septal area, hippocampus, and striatum and the abnormal metabolism of opioid peptides in the hippocampus and striatum of seizure-susceptible El mice, which are involved in the pathogenesis of seizures. However, these findings suggest that the ME-LI does not necessarily reflect the bioactive methionine enkephalin (ME). Herein, we measured the biologically active peptide, ME excluding cross-reactive substances by using HPLC coupled with radioimmunoassay to clarify the abnormal function of enkephalinergic neurons in the El mouse brain. The ME content in 25-day-old El mice that had no seizures was significantly decreased in the hippocampus and septal area, as compared with corresponding regions in ddY mice (seizure-nonsusceptible; the mother strain of El). At the age of 50 days when El mice displayed abortive seizures, this content in both stimulated El[s] and nonstimulated El[ns] was significantly reduced in the septal area and cerebral cortex. At the age of 150 days when El mice exhibit tonic-clonic seizures, this content in both El[s] and El[ns] was significantly reduced in the septal area, cerebral cortex and striatum. These findings were generally compatible with our previous findings. This study further supports our hypothesis that a deficit of anticonvulsant endogenous ME, in the cerebral cortex, septal area, and hippocampus of seizure-susceptible El mice play an important role in the pathogenesis of seizures.

Animals↗
PubMed1995

Increasing the thermal dose in transurethral microwave thermotherapy produces no improvement in therapeutic efficacy.

BACKGROUND: Transurethral microwave thermotherapy (TUMT) is a minimally invasive treatment for benign prostatic hyperplasia (BPH). It has been reported that increased thermal dose and higher intraprostatic temperatures resulted in improved clinical response. Recently we treated BPH patients with the prostatron device using a new version of software (Prostasoft 2.5), which was intended to increase thermal delivery by allowing maximum power up to 70W. The safety and clinical results were compared between the patients treated with Prostasoft 2.5 and those treated with the currently available software (Prostasoft 2; maximum power up to 50W). METHODS: A total of 105 patients were treated successively with two treatment protocols. Sixty-three patients were treated with Prostasoft 2 between September 1992 and July 1993, while 42 were treated with Prostasoft 2.5 between August 1993 and April 1994. Therefore, this investigation was a retrospective nonrandomized study. There was no significant difference in the baseline patient characteristics between the two groups. RESULTS: Total thermal dose delivered to the prostate was significantly higher in the Prostasoft 2.5 group than that in the Prostasoft 2 group (137 kJ versus 116 kJ, P < 0.05). No serious complications were encountered in either group. Six months after TUMT, in both the Prostasoft 2.5 and Prostasoft 2 groups there was an improvement in patient condition as measured by the mean I-PSS, QOL, and peak flow rate values, as well as the overall therapeutic efficacy. The two groups differed in the amount of posttreatment improvement from between 8% and 22%, but this difference was not statistically significant. CONCLUSIONS: Our study suggests that higher thermal dose attained by Prostasoft 2.5 does not necessarily result in more pronounced clinical improvement, although clinical response to TUMT has often been reported to be dependent upon thermal dose.

Aged↗
PubMed1995

Transurethral microwave thermotherapy for benign prostatic hyperplasia: clinical results after a 1-year follow-up.

Since September 1992, 63 patients with symptomatic benign prostatic hyperplasia (BPH) have been treated with transurethral microwave thermotherapy (TUMT) using the Prostatron device. The International Prostate Symptom Score (I-PSS) and quality of life (QOL) score were used to evaluate subjective symptoms. The mean I-PSS (total, irritative and obstructive scores) and QOL scores had decreased by 40, 38, 45 and 40%, respectively, at 12 months (p < 0.0001). While the mean peak flow rate had increased by 72% (p < 0.001). The clinical efficacy at 12 months was 42%, using a modification of the response criteria proposed at the 2nd International Consultation on Benign Prostatic Hyperplasia. There were no significant differences in the baseline and treatment parameters between those who responded favorably to TUMT and those who did not. The total thermal dose delivered to the prostate did not predict clinical response. However, there was a positive correlation between I-PSS or QOL at baseline and % reduction at 3, 6 and 12 months, and a negative correlation between peak flow rate at baseline and % increase at 3 and 6 months. There were no major complications associated with TUMT during the follow-up period. In summary, our 1-year clinical results are compatible with previous reports, suggesting that TUMT is a safe, effective and lasting non-surgical treatment for BPH. However, evaluation of efficacy should be based on uniform criteria to facilitate comparisons of different clinical trials. The most suitable patient profiles for TUMT could not be identified by retrospective analysis.

Aged↗
PubMed1995

[Immunohistochemical study of PCNA, EGFR, c-erbB-2 and p53 in carcinomas of large intestine].

Immunohistochemical stainings for EGFR, c-erbB-2, p53 and PCNA were performed on 36 and 30 cases of intramucosal and advanced carcinomas of large intestine. Positive rate was 58.3%, 41.6%, 58.3% and 60.6% for EGFR, c-erbB-2, p53 and PCNA in the intramucosal cases, and 66.7%, 50%, 66.7% and 72.6% in the advanced ones, respectively. Relationship between EGFR and c-drbB-2 was more significant in the advanced carcinomas than that in the intramucosal ones. It seemed likely that relationship between p53 and c-erbB-2 was more significant than that between p53 and EGFR. Positive rate of PCNA was of intimate relationship among that of EGFR, c-erbB-2 and p53, and the positive rate increased in the advanced carcinomas.

Biomarkers, Tumor↗
PubMed1995

[A case of granulomatous orchitis].

A 69-year-old man complained of a painless left scrotal swelling. The scrotal mass was enlarged to a hen's egg size with a smooth surface. The scrotal ultrasonogram showed diffuse hypoechogenicity. A testicular tumor was suspected and left high orchiectomy was performed. Histopathological diagnosis was granulomatous orchitis.

Aged↗
PubMed1995

Effects of bifemelane hydrochloride on plasma neuropeptide Y, 3-methoxy-4-hydroxyphenylethylene glycol and 5-hydroxy-indole acetic acid concentrations in patients with cerebral infarction.

Bifemelane hydrochloride (BH) is widely employed in Japan in the treatment of cerebral infarction patients with depressive symptoms and its antidepressant action is considered to be caused by the normalizing effects of neurotransmitters. The relationship between the normalizing effects of neurotransmitters of BH and the depressive state of patients with cerebral infarction was examined. BH 150 mg/day was administered for three months to 13 cerebral infarction patients with depressive state. We measured the plasma neuropeptide Y (NPY), 3-methoxy-4-hydroxyphenylethylene glycol (MHPG) and 5-hydroxy-indole acetic acid (5-HIAA), and assessed the depressive symptoms using the 21-item Hamilton's Rating Scale for Depression (HRSD) before and after administration of BH. After treatment, the plasma NPY concentration was significantly increased, the plasma MHPG concentration and total score of HRSD were significantly decreased, and the plasma 5-HIAA concentration showed no changes. These findings suggest that the antidepressant effect of BH is caused by the normalizing effects of NPY and noradrenalinergic neurons.

Aged↗
PubMed1994

Polar lipids of a non-alkaliphilic extremely halophilic archaebacterium strain 172: a novel bis-sulfated glycolipid.

Extremely halophilic archaebacteria which require high salt concentrations for growth and survival contain glycerol diether analogues of phospholipids and sulfated glycolipids as major membrane polar lipids. A non-alkaliphilic, non-pigmented rod-shaped extreme halophile, isolated from sea sand in Japan and designated 'strain 172', was found to contain two phospholipids, phosphatidylglycerol (PG) and phosphatidylglyceromethylphosphate (PGP-Me), derived from both C20-C20- and C20-C25-glycerol diethers, and a novel major glycolipid (designated SGL-X). This glycolipid has been identified as a bis-sulfated diglycosyl C20-C20- or C20-C25-glycerol diether, on the basis of its TLC mobility, positive-staining behavior with sugar and sulfate-staining reagents, its mole ratio sulfate/glycolipid = 2.2, and by spectrometric analysis (IR and FAB-MS) of the intact and the desulfated SGL-X. The sugars were identified as mannose and glucose, after acid hydrolysis of SGL-X, by paper chromatography of the free sugars and GC-MS of the derivatized sugars (alditol acetates). Permethylation analysis and 1H- and 13C-NMR analysis established the position and configuration of the sugar linkages and the positions of the sulfate groups. The final structure of SGL-X (now designated S2-DGD-1) is proposed to be: 2,3-diphytanyl- or phytanyl-sesterterpenyl-1-[2,6-(HSO3)2-alpha-Manp-1--> 2- Glcp]-sn-glycerol. This lipid is the first bis-sulfated glycolipid to be reported in extremely halophilic archaebacteria, and is the first in the biosphere that possesses two sulfate groups attached to the same monosaccaride.

Archaea↗
PubMed1994

[Clinical study of 15 children with acute suppurative thyroiditis].

From 1969 to 1990, 15 children with acute suppurative thyroiditis (AST) were diagnosed in our hospital. Their clinical, laboratory and radiologic findings were reviewed. The characteristic features were as follows: 1) Males to female ratio was 1.5:1. 2) The ages at diagnosis ranged from 3 to 14 years, with a mean age of 6 years. 3) A painful, tender mass in the anterior neck was detected in all cases and fever was detected in 10 cases (67%). 4) The left lobe of the thyroid was affected in 11 cases (73%), whereas the right lobe was affected in the remaining 4 cases. No cases was bilateral. 5) Five cases (33%) were found to be recurrent. 6) Eight pathogenic organisms were identified on culture from 7 cases; among them 3 were due to anaerobic pathogen. 7) Leukocytosis was increased and acute-phase reactant tests were positive in most cases. 8) Thyroid function was found to be normal in all 9 cases examined. 9) Radiologic studies, which included radionuclide thyroid scan, ultrasonography, computed tomography and barium esophagogram, were very helpful for the diagnosis of AST. 10) A barium esophagogram was performed in 9 cases and a fistula originating from the pyriform sinus was found in 4 cases (44%). 11) Three cases (20%) had the complete removal of the fistula as a permanent cure. This report summarizes the clinical features of 15 children with acute suppurative thyroiditis diagnosed in our hospital during the past twenty years.

Acute Disease↗
PubMed1994

Reversibility of transient focal cerebral ischemia evaluated by somatosensory evoked potentials in cats.

We designed this study to determine whether somatosensory evoked potentials (SEP) could be a reliable indicator to detect development of cerebral infarction or to predict reversibility of cerebral ischemia by investigating relationship among SEP, local cerebral blood flow (l-CBF), and histological changes after transient occlusion of the middle cerebral artery (MCA) in 36 cats. In 24 cats (group 1), gradual recovery of the cortical SEP was observed despite continued MCA occlusion, whereas the SEP remained lost in the remaining 12 cats (group 2). In group 1, amplitude of cortical SEP recovered completely 6 hours after recirculation following 30, 60, or 120 minutes of MCA occlusion, and only one developed cortical infarction. In six cats of group 2, the circulation was restored after 30 minutes of MCA occlusion. All showed complete recovery of SEP amplitude and none developed cortical infarction. When the MCA occlusion lasted 60 minutes in the remaining six cats, there was no recovery of the SEP amplitude and large cortical infarction was found in all six cats. Our findings suggest that SEP is a useful monitor for detecting cerebral infarction after MCA occlusion and that the critical time to avoid cerebral infarction would be 30 minutes when cortical SEP remains lost.

Animals↗