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Biomedical subjects

Y Hirose

Publications and source records attributed to Y Hirose.

At least 163 records · Page 9Linked to original sources
PubMed1996

Elevated serum levels of manganese superoxide dismutase in polymyositis and dermatomyositis.

We studied serum concentrations of manganese superoxide dismutase (Mn SOD) and copper-zinc superoxide dismutase (Cu/Zn SOD) in 22 patients with polymyositis and dermatomyositis (PM/DM), 87 patients with four types of muscular dystrophy, 20 patients with amyotrophic lateral sclerosis, and 15 patients with collagen vascular diseases (CVD). Serum levels of Mn SOD were increased only in the patients with PM/DM and CVD, and the elevation was more prominent in those with PM/DM. Levels of Cu/Zn SOD were slightly elevated in some patients with PM/DM and Duchenne muscular dystrophy. In patients with PM/DM, the change in Mn SOD levels corresponded to disease activity as closely as or more closely than those of creatine kinase. The results indicate that serum Mn SOD may be a useful clinical marker for PM/DM.

Adolescent↗
PubMed1996

Maladaptation of vascular response in frontal area of patients with orthostatic hypotension.

UNLABELLED: To clarify the relationship between abnormalities in cerebral blood flow (CBF) and in blood pressure regulation, we performed 99mTc-HMPAO brain SPECT in association with measurement of plasma norepinephrine and blood pressure in both the upright and supine positions. METHODS: We studied six patients with orthostatic hypotension and six normal patients. No patient had any significant stenosis of the carotid arteries on echocardiography-Doppler ultrasound and no abnormalities on brain MRI or CT. Changes in systolic blood pressure were monitored during the upright test, and 8-ml blood samples were taken at baseline and at 1 and 5 min after the upright position. RESULTS: Systolic blood pressure decreased by a mean of 38 +/- 10 and 9 +/- 3 mmHg in the orthostatic hypotension and normal groups, respectively. Compared with baseline values, plasma norepinephrine levels at 1 and 5 min after the upright test did not increase in the orthostatic hypotension group but did increase significantly in the normal group. In the orthostatic hypotension group, 99mTc-HMPAO brain SPECT showed postural cerebral hypoperfusion in the bilateral frontal areas, of which the mean count ratio of the frontal-to-cerebellar area between the upright and supine positions significantly changed from 0.871 +/- 0.029 to 0.942 +/- 0.067 and from 0.881 +/- 0.035 to 0.954 +/- 0.073 in the right and left areas, respectively. No postural change in CBF was evident in other areas in the orthostatic hypotension group. In the normal group, there were no such changes in CBF, blood pressure and plasma norepinephrine levels during the upright test. CONCLUSION: Postural cerebral hypoperfusion in the frontal areas in the orthostatic hypotension group might relate to maladaptation of the vascular response during the upright test.

Blood Pressure↗
PubMed1996

[Evaluation of remote effect to supratentorial areas in cerebellar infarction: a semiquantitative analysis using 99mTc-HM-PAO SPECT].

We studied 18 patients with unilateral cerebellar infarction to investigate its remote effect to the supratentorial areas with 99mTc-HM-PAO SPECT. Asymmetry indexes (AI) were calculated in the cerebellum and in seven supratentorial areas (thalamus, basal ganglia, superior and inferior frontal areas, temporal area, parietal area and occipital area). Mean AIs of supratentorial areas ranged from -0.64 +/- 2.74% to +1.04 +/- 2.03%. In cerebellar infarction of acute or subacute phase, the mean AI showed larger values (+1.13%) than that of chronic phase (+0.21%), but this difference did not reach statistical significance. There was no significant difference among supratentorial AIs grouped according to cerebellar infarction size. There was also no significant correlation among AIs of cerebellar and the supratentorial areas (r = -0.32 to +0.38). Crossed hemispheric hypoperfusion is thought to be related to the interruption of cerebellocortical tracts. We concluded that the detection of the remote effect to supratentorial areas in cerebellar infarction was difficult with 99mTc-HM-PAO SPECT.

Adult↗
PubMed1996

[Usefulness of 123I-BMIPP scanning for distinction of ischemic from nonischemic dilated cardiomyopathy].

To determine if imaging of blood flow (using 201Tl) and fatty acid (using 123-I-BMIPP) with SPECT can distinguish cardiomyopathy of coronary artery disease from nonischemic dilated cardiomyopathy, 24 patients with severe left ventricular dysfunction were evaluated. The origin of left ventricular dysfunction had been previously determined by coronary angiography to be ischemic (9 patients) or nonischemic (15 patients). Images were visually analyzed by three observers on a graded scale (score 0; normal, 1; mild uptake reduction, 2; severe uptake reduction, and 3; defect) in 20 left ventricular segments revealed higher defect score in ICM compared with NCM for 123I-BMIPP (35.5 +/- 14.4 versus 14.1 +/- 9.3, p <0.0005) and 201Tl (27.6 +/- 14.6 versus 12.1 +/- 7.4, p <0.005). The defect score/segment ratio also revealed higher value in ICM compared with NCM for 123I-BMIPP (2.25 +/- 0.52 versus 1.36 +/- 0.36, p <0.0001) and 201Tl (1.92 +/- 0.51 versus 1.24 +/- 0.42, p <0.005). Myocardium of ICM is more severely damaged than that of NCM. Thus, noninvasive SPECT imaging with 123I-BMIPP is helpful in distinguishing patients with severe left ventricular dysfunction secondary to coronary artery disease from those with nonischemic cardiomyopathy.

Adult↗
PubMed1996

[Significance of 123I-metaiodobenzylguanidine SPECT for detecting left ventricular involvement in patients with arrhythmogenic right ventricular dysplasia].

The right ventricle being primarily involved in ARVD, recent reports indicate the presence of histological and functional abnormalities in the left ventricle for some patients with ARVD. The aim of this study was to evaluate the significance of myocardial sympathetic dysfunction as an early sign of left ventricular (LV) involvement by 123I-MIBG (MIBG) SPECT and to compare the findings with those of 201TlCl (Tl) SPECT, radionuclide left ventriculography, ultrafast computed tomography (UFCT), magnetic resonance imaging (MRI) and echo-cardiography in 10 patients (pts) with ARVD. MIBG defects in LV regions were detected in 9 pts. Seven of the 9 pts showed MIBG defects in LV regions adjacent to RV. The subjects were divided into 2 groups based on left ventriculography, 5 with normal LVEF (> 55%) and 5 with reduced LVEF. In the normal LVEF group, 4 pts showed MIBG defects and 2 pts showed TI defects, and MIBG defects were larger than TI defects (ES: 14 +/- 6 vs. 5 +/- 7, p <0.05). In reduced LVEF group, all of 5 pts showed MIBG and TI defects, and MIBG defects were larger than TI defects (ES: 42 +/- 12 vs. 25 +/- 3, p <0.05). In comparison with normal LVEF group, reduced LVEF group showed larger and more severe MIBG defects (ES: 42 +/- 12 vs. 14 +/- 6, p <0.01, SS: 44 +/- 31 vs. 8 +/- 7, p <0.05). UFCT and MRI showed abnormal findings indicating LV fatty infiltration in only 3 of reduced LVEF group. Thus, MIBG showed abnormal distributions in the left ventricle with the highest frequency in all these modalities. These results suggest that MIBG SPECT provides a sensitive marker for detecting LV involvement in ARVD. Also, the extent of MIBG distribution abnormalities is helpful in assessing the severity of left ventricular involvement in patients with ARVD.

3-Iodobenzylguanidine↗
PubMed1996

[Amrinone administration exerts no deleterious effect on platelet counts and blood transfusion volume during CABG].

The purpose of this study was to examine retrospectively the effect of amrinone on platelet counts and blood transfusion volume during CABG. Patients were divided into two groups. Amrinone group included 40 patients and for comparison another group included 33 patients who had undergone CABG without amrinone. Anesthesia and surgical procedures were standardized and similar for all patients. Platelet counts and hematocrit levels were measured in the arterial blood before CPB, at the end of CPB (after treatment with amrinone in amrinone group), 1 day, 3 days, and 7 days after surgery. Time course of changes in platelet counts was the same between the groups at the following points: before CPB, after CPB, 1 day, 3 days, and 7 days after surgery. We administered amrinone to patients who underwent CABG. The titrated dose of amrinone (about 29mg.kg-1) has not affected the time course of changes in platelet counts and blood transfusion volume.

Aged↗
PubMed1996

Cerebral hypoperfusion in orthostatic hypotension with globally denervated myocardium.

A 57-yr-old woman had frequent syncope when rising from a seated position. Her blood pressure fell from 140/80 mmHg to 60-70/40 mmHg while changing positions. Iodine-123-metaiodobenzylguanidine ([123I]MIBG) did not accumulate in the heart, whereas 201Tl-Cl (201Tl) did. Raise-up 99mTc-hexamethyl-propyleneamine oxime (99mTc-HMPAO) brain SPECT revealed decreased activity in the bilateral frontal areas, and subsequent supine 99mTc-HMPAO brain SPECT revealed filling in these areas, indicating that the cerebral blood flow (CBF) was transiently decreased in the frontal areas more than others in a standing position. The plasma norepinephrine (NE) level of this patient was normal during supine rest, but when she stood up, failure to increase the plasma level of NE uncovered a sympathetic nervous dysfunction. The CBF abnormality in patients with orthostatic hypotension may be due to a "functional" hemodynamic mechanism that induces orthostatic stress. This patient had transient hypoperfusion in the frontal areas when standing, without organic cerebral arterial stenosis. Only CBF in the frontal areas revealed relative hypoperfusion. These regions might be highly susceptible to a change in blood flow. The causes of orthostatic hypotension of this patient were autonomic failure with a disturbance of the sympathetic nerve endings, which was revealed by 99mTc-HMPAO brain SPECT and cardiac [123l]MIBG imaging.

3-Iodobenzylguanidine↗
PubMed1996

[Idiopathic intracranial hypotension associated with decreased blood concentration of vitamin A].

We report a case of idiopathic intracranial hypotension, a clinically rare syndrome. A 28-year-old woman was admitted with orthostatic headaches associated with nausea secondary to intracranial hypotension. Lumbar puncture yielded an opening pressure of 4 cmH2O in the lateral recumbent position, and the spinal fluid protein concentration was 56 mg/dl. There was no history of lumbar puncture or clear history of head trauma before the onset of symptoms. Spinal and cranial MRI showed no evidence of CSF leakage, and there was diffuse meningeal enhancement following gadolinium infusion. Cranial MRI showed no evidence of brain displacement due to low CSF pressure, such as tonsillar herniation. Radioisotope cisternography (RIC) showed rapid accumulation of isotope within the bladder and early disappearance of radioactivity from the head. About 2 months later the headaches resolved spontaneously, and repeated lumbar puncture yielded opening pressure elevation to 10.5 cmH2O with a decrease in protein concentration to 28 mg/dl. The abnormal MRI and RIC findings had become normal. On the other hand, the patient had a low blood concentration of vitamin A, which is thought to play some role in the production of CSF. The results of RIC suggested that the patient may have become symptomatic because of undetectable CSF leakage or hyperabsorption, but diminished production of CSF due to lower blood vitamin A concentrations may also have been a factor predisposing to this syndrome.

Adult↗
PubMed1996

Relationship between peptidase activity from Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus and attachment loss.

As a diagnostic test, "Periocheck" can detect the N-carbobenzoxyglycyl-glycy-arginyl peptidase that is produced by Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus. The aim of this study was to clarify the relationship between peptidase activity and attachment loss. After Phase 1 and surgical therapy, a total of 111 sites from 47 adult periodontitis patients were divided into four groups according to peptidase activity (trypsin unit, TU): A, < 0.1 TU; B, 0.1-0.2 TU; C and D > or = 0.2 TU. All sites in groups A, B, and C were untreated, whereas both subgingival 3% hydrogen peroxide irrigation and 2% minocycline application were undertaken every 45 days throughout the experiment in group D. All subjects were recalled at 3-month intervals. Peptidase activity and clinical assessments were measured for the 18-month period. Significant attachment loss associated with high values of the peptidase activity was found through the experimental period in groups B and C. In contrast, no obvious change of attachment loss was found in groups A and D following low peptidase activity at 6, 12, and 18 months. The mean attachment loss throughout the 18-month period was 0.22 mm in group A, 1.04 mm in group B, 1.53 mm in group C, and -0.35 mm in group D. Probing depth and percentages of bleeding on probing significantly increased in group C, whereas they decreased in group D. This peptidase test displayed a 77.8% sensitivity and 68.6% specificity regarding the detection of > or = 1 mm attachment loss with a cut-off value of 0.1 TU. Multiple linear regression analysis showed a close relationship between peptidase activity and predictable attachment loss within a 12-month period. These findings suggest that this peptidase test is useful in identifying the risk sites for predictable attachment loss.

Bacterial Proteins↗
PubMed1995

DNA fragmentation in granular cells of human cerebellum following global ischemia.

Vulnerability of human cerebellum in two autopsy cases following global brain ischemia was examined histologically by using a specific in situ nick-end labeling method for DNA breaks. In both cases, DNA fragmentation was observed in approximately one-third of the granular cells in cerebellar cortex, whereas Purkinje cells were still alive and no DNA fragmentation was recognized in the nuclei. The present study suggests that some granular cells of cerebellar cortex are more vulnerable to transient ischemia than Purkinje cells and death of granular cells is induced by an apoptotic DNA fragmentation following global brain ischemia.

Adult↗
PubMed1995

Chemoprevention of azoxymethane-induced colon carcinogenesis by dietary feeding of S-methyl methane thiosulfonate in male F344 rats.

Modifying effects of dietary exposure of S-methyl methane thiosulfonate (MMTS) isolated from cauliflower Brassica oleracea L. var. botrytis on rat colon carcinogenesis induced by azoxymethane (AOM) and on the expression of cell proliferation biomarkers were investigated in two experiments. In experiment 1, male F344 rats were given three s.c. injections of AOM (15 mg/kg body weight) and fed 100 ppm MMTS for 5 weeks, starting 1 week before the first dose of AOM. The frequency of colonic aberrant crypt foci was determined at 5 weeks after the start. Feeding of 100 ppm MMTS for 5 weeks significantly decreased the number of aberrant crypt foci/colon. Colonic mucosal ornithine decarboxylase activity and the number of silver-stained nucleolar organizer regions per nucleus in colonic epithelium were significantly decreased by MMTS treatment compared with those of AOM alone. In experiment 2, effects of dietary feeding of MMTS at two doses (20 and 100 ppm) during the postinitiation phase on intestinal tumorigenesis initiated with AOM were investigated by using a long-term experiments in male F344 rats. Incidence of intestinal neoplasms of rats fed MMTS-containing diets after AOM exposure were reduced in a dose-dependent manner. Feeding of MMTS during the postinitiation phase decreased the number of aberrant crypt foci/colon, colonic ornithine decarboxylase activity, 5-bromodeoxyuridine-labeling index in colonic epithelium, and polyamine level in blood compared with those of AOM alone. These results suggest that MMTS might be a possible chemopreventive agent for intestinal neoplasia.

Animals↗
PubMed1995

Expression, purification, and neurotrophic activity of amyloid precursor protein-secreted forms produced by yeast.

The secreted form of amyloid precursor protein (APPs) including most of the extracellular domain of APP is released from the cell surface, suggesting physiological significance of APPs in vivo. We used the methylotrophic yeast Pichia pastoris as a host system for the production of recombinant APPs (rAPPs). Two rAPPss derived from isoforms of APP (APP695 and APP770) were secreted into the culture medium from the yeast, which carried cDNA encoding the N-terminal portion of APP under the control of a P. pastoris alcohol oxidase promoter. Like APPss produced by the transfected COS-1 cells, the purified rAPPss from yeast were shown to be biologically active in terms of neurite outgrowth of embryonic rat neocortical explants. These rAPPss could be valuable tools for investigating the biological functions of APPss.

Amino Acid Sequence↗
PubMed1995

Suppression of azoxymethane-induced colonic aberrant crypt foci by dietary exposure to a novel synthesized retinoidal butenolide, 5-hydroxy-4-(2-phenyl-(E)ethenyl)-2(5H)-furanone, in rats.

The modifying effect of dietary exposure to a novel synthesized retinoidal butenolide, 5-hydroxy-4-(2-phenyl-(E)ethenyl)-2(5H)-furanone (KYN-5) on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) was investigated in male F344 rats. Animals were given weekly s.c. injections of AOM (15 mg/kg body wt.) for 3 weeks to induce ACF. These rats were fed diet containing 100 or 200 ppm KYN-54 for 5 weeks, starting 1 week before the first dosing of AOM. All rats were killed 2 weeks after the last AOM injection, to measure the number of ACF, ornithine decarboxylase (ODC) activity, mucosal polyamine level, and silver-stained nucleolar organizer regions protein (AgNORs) count per nucleus in the colon. In rats given AOM and KYN-54, the frequency of ACF/colon was significantly decreased compared with that in rats given AOM alone. ODC activity and polyamine levels, and the mean AgNORs number in the colon of rats given AOM and KYN-54 at both doses were also significantly lower than that of rats treated with AOM alone. These results provide further evidence that KYN-54 could be a chemopreventive agent against rat colon carcinogenesis.

4-Butyrolactone↗
PubMed1995

Myocardial damage after successful thrombolysis is associated with the duration of ST re-elevation at reperfusion.

The purpose of this study was to investigate the significance of ST re-elevation at reperfusion using strict criteria for patient inclusion and exclusion. Twenty-nine patients who had a first anterior infarction with single-vessel disease, successful recanalization by intracoronary thrombolysis (ICT) with urokinase, and an angiographically confirmed patent infarct-related artery after 4 weeks, were divided into three groups according to the deviation of the ST segment at reperfusion: Group A, 10 patients with sustained ST re-elevation; Group B, 10 patients with transient ST re-elevation; and Group C, 9 patients with ST reduction. Left ventricular (LV) function was evaluated from cineventriculograms performed in the 30 degrees right anterior projection 4 weeks after ICT. LV ejection fraction and regional wall motion of the infarct area, evaluated by the centerline method (SD/chords), were significantly lower in Group A (44 +/- 10%, -3.2 +/- 0.4) than in Group B (61 +/- 9%, -1.9 +/- 0.7) and Group C (60 +/- 5%, -2.0 +/- 0.4) (p < 0.01). Peak creatine kinase (CK) activity was significantly higher in Group A (5848 +/- 2112 IU) than in Group B (2485 +/- 1254 IU) and Group C (1889 +/- 1525 IU) (p < 0.05). These data suggest that a sustained ST re-elevation at reperfusion was strongly associated with marked LV dysfunction and higher peak CK activity. It was concluded that sustained, not transient, ST re-elevation associated with successful reperfusion indicates extensive myocardial damage.

Aged↗
PubMed1995

No involvement of Ki-ras or p53 gene mutations in colitis-associated rat colon tumors induced by 1-hydroxyanthraquinone and methylazoxymethanol acetate.

1-Hydroxyanthraquinone (1-HA), which is present in some herbs, and methylazoxymethanol (MAM) acetate, a metabolite of azoxymethane, show synergistic carcinogenicity in rat colon, and 1-HA induces ulcerative changes with simultaneous severe inflammation of the entire colon. In this study, mutations in Ki-ras (exons 1 and 2) and p53 (exons 4-7) were studied by polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) analysis. Of 18 adenomas and 38 adenocarcinomas induced in male F344 rats (52 tumors induced by 1-HA plus MAM acetate, three by 1-HA alone, and one by MAM acetate alone), no mutations in Ki-ras or p53 were detected under two conditions of PCR-SSCP analysis. Because human colon carcinomas from patients with ulcerative colitis have a very low incidence of Ki-ras mutation, this experimental system would be a good animal model of human colon carcinomas with ulcerative colitis and of human colon carcinomas without Ki-ras or p53 mutations.

Animals↗