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Biomedical subjects

H Asano

Publications and source records attributed to H Asano.

At least 109 records · Page 6Linked to original sources
PubMed1994

The predictive power of self-rated health, activities of daily living, and ambulatory activity for cause-specific mortality among the elderly: a three-year follow-up in urban Japan.

OBJECTIVE: To examine the predictive power of self-rated health, activities of daily living (ADL), and ambulatory activity for different causes of death in a representative sample of older persons. DESIGN: Three-year prospective cohort study. SETTING: Sendai City, Japan. PARTICIPANTS: 2,552 persons 65 years and older at baseline in 1988. MEASUREMENTS: Independent variables (measured by self-report of participants) were age, sex, self-rated health, ADL, ambulatory activity level, and use of medical care. Dependent variables were mortalities from cancer, stroke, and heart disease. MAIN RESULTS: Self-rated health significantly predicted cancer mortality but not the other two causes of mortality. ADL disability was a significant predictor for stroke mortality, and limitation in ambulatory activity significantly increased the risk of heart disease mortality. The associations between ADL and stroke mortality as well as between ambulatory activity and heart disease mortality remained significant even after excluding those who reported having the index disease in 1988. CONCLUSION: The predictive powers of self-rated health, ADL function, and ambulatory activity varied significantly with the underlying causes of death among the elderly.

Activities of Daily Living↗
PubMed1994

Growth analysis of marrow CD34-positive hematopoietic progenitor cells in patients with myelodysplastic syndromes.

The in vitro colony-forming capacities of marrow CD34-positive (CD34+) cells from 25 patients with myelodysplastic syndromes (MDS) were studied. In all patients this purified cell population showed erythroid (burst-forming unit erythroid; BFU-E) or non-erythroid colony growth, both of which were more restricted than non-purified mononuclear cell population under stimulation with erythropoietin (EPO) or granulocyte/macrophage colony-stimulating factor (GM-CSF) alone. MDS patients examined were put into two groups; refractory anemia (RA) or RA with ringed sideroblasts (RA/RARS) and RA with excess of blasts (RAEB) or RAEB in transformation (RAEB/RAEB-t). The CD34+ cells of both RA/RARS and RAEB/RAEB-t exhibited a similarity to the cells of normal individuals in their responsiveness to the addition of interleukin 6 (IL-6), IL-3 or stem cell factor (SCF). SCF caused powerful but highly variable responses in both erythroid and nonerythroid colony formation as compared with IL-6 or IL-3. We demonstrated that MDS marrow hematopoietic progenitor cells reactive to GM-CSF or EPO were additionally stimulated with early-acting hematopoietic growth factors including IL-6, IL-3 and SCF in a fashion similar to those of normal individuals.

Adult↗
PubMed1994

Effects of stem cell factor (SCF) on human marrow neutrophil, neutrophil/macrophage mixed, macrophage and eosinophil progenitor cell growth.

The effects of stem cell factor (SCF) on the subpopulations of granulocyte/macrophage colony-forming units (CFU-GM) were examined. Hematopoietic progenitor cells were enriched from normal adult bone marrow specimens by immunomagnetic beads using an anti-CD34 antibody and lineage marker antibodies for positive selection and negative selection, respectively. SCF enabled neutrophil and neutrophil/macrophage mixed progenitors to respond to granulocyte/macrophage colony-stimulating factor (GM-CSF) or interleukin 3 (IL-3) and to develop the colony and further cluster formation. The neutrophil colonies stimulated by GM-CSF or IL-3 consisted mainly of immature cells, while the colonies stimulated by granulocyte colony-stimulating factor (G-CSF) consisted of mature neutrophils irrespective of the addition of SCF. In macrophage and eosinophil lineages, SCF augmented the colony formation in the presence of GM-CSF or IL-3, whereas the enhancement of total progenitor cell growth (colonies plus clusters) was not so marked as compared with the neutrophil lineage. Time-course observation revealed that SCF could stimulate macrophage and eosinophil progenitors to form colonies rapidly. These findings indicate that SCF acts on late myeloid progenitor cells in manners different from the lineages of commitment.

Adult↗
PubMed1994

[Effect of LAK cells and BRM on the growth of pancreatic cancer cells injected into nude mice].

Effect of lymphokine activated killer (LAK) cells induced by in vitro or in vivo stimulation with biological response modifier (BRM) such as recombinant interleukin-2 (rIL-2) or OK-432 on the growth of pancreatic cancer cells injected into nude mice were studied. Human rIL-2 stimulated spleen cells from BALB/c nu/nu mice were used as effector LAK cells. Human pancreatic cancer cell lines PK-1 and PK-9 were used as target for cytolytic activities against pancreatic cancer. Cytolysis was estimated by 51Cr release assay in vitro, and tumor growth inhibition was estimated by Winn assay in vivo. NK, LAK and pancreatic cancer cell killing activities of LAK cells were elevated to significantly high level of 82%, 70% 51% (PK-1) and 33% (PK-9) respectively on the 2nd day after cultivation with rIL-2. Significantly high level of tumor inhibition rate (98%) was obtained when PK-1 cells were injected into nude mice subcutaneously with LAK cells compared with injection of PK-1 cells only (control). Spleen cells induced from nude mice injected intraperitoneally with rIL-2 or OK-432 showed significantly high cytolytic activities. These results indicate that LAK cells induced by in vitro or in vivo stimulation with BRM could inhibit the growth of pancreatic cancer.

Animals↗
PubMed1994

Cardiac effects of the novel pyridazinone derivative 6-[4-[2-[3-(5-chloro-2-cyanophenoxy)-2-hydroxypropylamino]- 2- methylpropylamino]phenyl]-4,5-dihydro-5-methyl-3(2H) pyridazinone monoethyl maleate and its metabolite in isolated heart preparations of guinea pigs and dogs.

The cardiovascular effects of 6-[4-[2-[3-(5-chloro-2-cyanophenoxy)-2- hydroxypropylamino]-2-methylpropylamino]phenyl]-4,5-dihydro- 5-methyl-3(2H) pyridazinone monoethyl maleate (salt) (TZC-5665, CAS 114856-47-2) and its main metabolite in human, M-2, were investigated in isolated atrial and ventricular muscles of guinea pigs and dogs, in guinea pig atrial and right ventricular papillary muscles. TZC-5665 showed negative chronotropic and inotropic effects, whereas M-2 showed a potent positive inotropic effect with a slight positive chronotropic effect. The positive inotropic effect of M-2 was not modified by phentolamine, propranolol and cimetidine, but completely depressed by carbachol. In blood-perfused dog heart preparations, M-2 increased the contractile force and coronary blood flow of paced papillary muscles and sinus rate. Although TZC-5665 scarcely affected the contractile force and sinus rate, it increased coronary blood flow. TZC-5665 scarcely affected atrio-ventricular (AV) conduction time, whereas M-2 slightly shortened AV conduction time. The rate of ventricular automaticity was slightly increased by M-2, but suppressed by TZC-5665 at higher doses. TZC-5665 showed a non-selective beta-adrenoceptor blocking activity comparable to that of propranolol in guinea-pig atrial and tracheal preparations. In enzyme preparations, TZC-5665 and M-2 were more potent and selective inhibitors of phosphodiesterase (PDE) III than milrinone. Combination of beta-adrenoceptor blocking effect of TZC-5665 and positive inotropic effect of M-2 could be useful in the treatment of congestive heart failure by mutual prevention of undesirable effects.

Adrenergic beta-Antagonists↗
PubMed1994

Analysis of the role of endothelin-A and endothelin-B receptors on nociceptive information transmission in the spinal cord with FR139317, an endothelin-A receptor antagonist, and sarafotoxin S6c, an endothelin-B receptor agonist.

Endothelin (ET)-A and ET-B receptors have been reported to exist in the spinal cord but the roles of ET-A and ET-B receptors in the spinal cord are poorly understood. To gain a better understanding of the roles of ET-A and ET-B receptors in nociceptive information transmission in the spinal cord, this study evaluated the effects of ET-1, ET-3, Sarafotoxin S6c (an ET-B receptor-selective agonist) and (R)2-[(R)-2-[(S)-2-[[1- (hexahydro-1H-azepinyl)]carbonyl]amino-4-methyl-pentanoyl]amino-3- [3-(1-methyl-1H-indolyl)]propionyl]amino-3-(2-pyridyl)propionic acid (FR139317, an ET-A receptor-selective antagonist) on the agitation behavior evoked by formaldehyde solution injection and on the thermal nociceptive test. The s.c. injection of formaldehyde solution into the hind paw evoked a biphasic flinching (phase 1, 0-9 min; phase 2, 10-60 min) of the injected paw. For the purpose of data analysis, phase 2 was further divided into two phases (phase 2a, 10-34 min; phase 2b, 35-60 min). Intrathecal injection of ET-1 depressed the phase 1 and 2 flinching behavior in a dose-dependent manner and this ET-1 effect was antagonized by FR139317. Intrathecal injection of either ET-3 or Sarafotoxin S6c enhanced the phase 2a flinching behavior in a dose-dependent manner. Intrathecal injection of the highest doses of ET-1, ET-3 and Sarafotoxin S6c had no effect on the thermal nociceptive test. These data indicate that ET-A and ET-B receptors have a powerful effect on spinal nociceptive processing evoked by formaldehyde solution injection but not that evoked by thermal stimulation.

Animals↗
PubMed1994

[Changes in physical disability among Japanese elderly].

In order to investigate the natural course of physical disability among the elderly, the ability to perform activities of daily living (ADL) was examined on a probability sample (N = 3384) of residents aged 65 years and over in Sendai City, Japan, in 1988 and 1991. Information on ability to perform four ADL tasks-dressing, eating, using the toilet, and bathing-were collected by self-report. In 1988, 7.2% of the males and 7.9% of the females reported at least one ADL dependency. The prevalence of disability was the highest in bathing, followed by dressing, using the toilet, and the lowest in eating. The Cox proportional hazard models on three-year mortality indicated that those who were ADL dependent at baseline had 4.1 times the mortality risk of those who were ADL independent. Among those who were ADL independent in 1988 and who were alive in 1991, 5.0% of the males and 4.8% of the females became dependent in at least one ADL task in 1991. The incidence of disability was the highest in bathing, followed by dressing, using the toilet, and the lowest in eating. Among those who were ADL dependent in 1988 and who were alive in 1991, about one-third of them improved in ADL functioning. Improvement was more common among those who were younger in age. These results suggest that levels of ADL functioning is highly dynamic, and that physical disability is, to a certain extent, reversible among the elderly.

Activities of Daily Living↗
PubMed1994

Prostaglandin H2 as an endothelium-derived contracting factor modulates endothelin-1-induced contraction.

OBJECTIVE: To investigate the possible involvement of prostaglandin H2, an endothelium-derived contracting factor in the rat aorta, in the development of the contraction induced by endothelin-1. METHODS: The aortic rings from spontaneously hypertensive rats (SHR) were prepared, and the changes of isometric tension of these rings developed by endothelin-1 were recorded with or without the treatment of several inhibitors or an antagonist. The concentrations of prostaglandins and thromboxane B2 in the bath solution with the rings contracted by endothelin-1 were measured by radioimmunoassay. The effects of a thromboxane A2/prostaglandin H2 receptor antagonist (ONO-3708) on endothelin-1-induced contraction were compared in SHR and Wistar-Kyoto (WKY) rats. RESULTS: Indomethacin (10(-5) mol/l) and ONO-3708 (10(-6) mol/l) significantly diminished endothelin-1 (3 x 10(-8) mol/l)-induced contractions in the aortic rings from SHR with but not without endothelium. The thromboxane A2 synthetase inhibitors OKY-046 (10(-5) mol/l) and RS-5186 (10(-5) mol/l) did not attenuate the contractions either with or without endothelium. Endothelin-1 significantly increased the release of 6-keto-prostaglandin F1 alpha, which is the metabolite of prostaglandin I2 and its precursor prostaglandin H2, from rings with endothelium of SHR, but the concentration of thromboxane B2 from aortic rings was unchanged. In the rings without endothelium the endothelin-1-induced release of 6-keto-prostaglandin F1 alpha was also observed. The half-maximal effective concentration of endothelin-1 for rings from SHR was shifted to the right by ONO-3708, but that of WKY rats was not changed, and significantly greater amounts of 6-keto-prostaglandin F1 alpha were released in the rings from SHR than in those from WKY rats by endothelin-1. CONCLUSIONS: Endothelin-1 induced the release of prostaglandin H2 from endothelial cells in the rat aorta, the effect being greater in the hypertensive state. The released prostaglandin H2, an endothelium-derived contracting factor, modulated the vasoconstriction that is induced by endothelin-1, another endothelium-derived contracting factor, in addition to the direct vasoconstrictive action of endothelin-1 on vascular smooth muscle.

6-Ketoprostaglandin F1 alpha↗
PubMed1993

Cloning and chromosome mapping of the human Mel-18 gene which encodes a DNA-binding protein with a new 'RING-finger' motif.

It has recently been reported that there exists a new 'RING-finger' protein family among the zinc-finger (Zf) proteins. Previously, we had isolated the mouse Mel-18 cDNA (mMel-18) encoding the nuclear RING-finger protein that exhibits an ability to bind to a nonspecific DNA column. Here, we have isolated and characterized the human Mel-18 cDNA (hMel-18) using the mMel-18 cDNA as a probe. The deduced hMel-18 protein contains 344 amino acids (38 kDa) with a RING-finger motif, a helix-loop-helix (HLH)-like structure and a Pro/Ser-rich region. The hMel-18 gene is conserved among vertebrates. Its mRNA is highly expressed in placenta, lung and kidney, but the level is low in liver, pancreas and skeletal muscle. Using in situ hybridization, we mapped hMel-18 to band q22 of chromosome 12. It is possible that the Mel-18/bmi-1 gene family represents a mammalian homologue of the Drosophila polycomb gene group.

Amino Acid Sequence↗
PubMed1993

Diagnosis of right ventricular infarction by overlap images of simultaneous dual emission computed tomography using technetium-99m pyrophosphate and thallium-201.

The validity of dual energy single-photon emission computed tomography (SPECT) with technetium-99m pyrophosphate (Tc-99m PPi) and thallium-201 for the diagnosis of right ventricular (RV) infarction, and the clinical features of RV infarction, were investigated in 190 patients with acute myocardial infarction. Diagnosis of RV infarction was performed by Tc-99m PPi accumulation in the RV myocardium on thallium-201 and Tc-99m PPi over-lay images at the dual SPECT with simultaneous imaging taken 2 to 9 days after the onset of myocardial infarction. Thirty RV infarctions were found among the 190 patients with left ventricular infarction (15.8%): 29 (97%) in association with the inferior and 1 (3%) with the lateral infarction. Tc-99m PPi accumulation was mostly observed in the posterior wall of the right ventricle. A total occlusion or a severe stenosis of the right coronary artery was demonstrated angiographically in 92% of the patients with RV infarction. The prevalence of RV infarctions was significantly lower in patients who achieved successful early reperfusion than in those who did not (26.7 vs 68.4%, respectively, p < 0.01). However, a successful early reperfusion therapy could not significantly decrease the rate of RV involvement in patients without significant collateral flow (p < 0.01). Thus, dual isotope SPECT with Tc-99m PPi and thallium-201 can be used as a reliable method for the diagnosis of RV infarction.

Aged↗
PubMed1993

The close relationship between DNA replication and the selection of differentiation lineages of human erythroleukemia cell lines K562, HEL, and TF1 into either erythroid or megakaryocytic lineages.

The selection of differentiation lineages into either erythroid or megakaryocytic series was analyzed with human erythroleukemia cell lines K562, HEL, and cytokine-dependent TF1. A tumor promoter, TPA, induced a megakaryocyte marker, glycoprotein IIb/IIIa (GP IIb/IIIa) or IIIa (GP IIIa), but suppressed erythroid differentiation. On the other hand, aphidicolin, which is a potent inhibitor of DNA replication, inhibited GP IIb/IIIa or IIIa expression, but induced the expression of erythroid phenotypes. These phenomena were observed in all erythroleukemia cell lines tested. The bromodeoxyuridine labeling experiments indicated that de novo DNA synthesis was completely suppressed by aphidicolin treatment but was well preserved in TPA-treated cells. Among these three cell lines, erythropoietin (EPO) treatment induced erythroid differentiation of TF1 cells, which was dependent on GM-CSF or IL-3. In this case, EPO functioned as the survival factor and mild stimulator for cell proliferation as well as the inducer of erythroid differentiation. However, when either GM-CSF or IL-3 was depleted from the culture medium, TF1 ceased cell growth; concomitantly, hemoglobin-positive cells appeared, which is consistent with the results obtained with aphidicolin. The incubation of K562 cells for 48 h with either TPA or aphidicolin induced the irreversible commitment of cells to megakaryocytic and erythroid lineages, respectively. Our results using three different erythroleukemia cell lines suggest that a possible linkage between the DNA replication system and the selection of a differentiation lineage is the common feature of human erythroleukemia cell lines, and that these culture systems provide a suitable model for the analysis of the signal transduction system for differentiation lineage selection.

Aphidicolin↗
PubMed1993

Role of prostaglandin H2 as an endothelium-derived contracting factor in diabetic state.

This study investigated the possible involvement of prostaglandin H2, an acetylcholine-induced endothelium-derived contracting factor in rat aorta, in the development of abnormality of the vasculature in diabetes. Rings of thoracic aorta were prepared from control Wistar-Kyoto and STZ-induced diabetic rats to examine the changes in isometric tension. In 10(-7) M norepinephrine-precontracted rings, acetylcholine induced relaxations, which were significantly impaired in diabetic rats. Inhibition of thromboxane A2-prostaglandin H2 receptors with ONO-3708 (10(-6) M) prevented the development of the impairment of relaxation in diabetic rats. Thromboxane A2 synthesis inhibition with OKY-046 (10(-5) M) did not affect the acetylcholine-induced relaxation in both control and diabetic rats. In aortic rings under resting tension, acetylcholine induced a contraction that was greater in diabetic than control rats, when the nitric oxide production was inhibited by NG-nitro-L-arginine methylester (10(-4) M). This acetylcholine-induced contraction was observed only in the rings with intact endothelium and was completely abolished by ONO-3708 (10(-6) M). The concentration of 6-keto-prostaglandin F1 alpha in the solution bathing diabetic rat aortic rings increased significantly after acetylcholine (10(-5) M) administration. Prostacyclin (10(-9)-10(-6) M) did not induce contractions at all. Prostacyclin is unlikely to mediate contractions because of its low contractile potency.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗
PubMed1993

The mouse Mel-18 "RING-finger" gene: genomic organization, promoter analysis and chromosomal assignment.

The chromosome gene for mouse Mel-18 (mMel-18) protein has been isolated and characterized. The entire mMel-18 gene is composed of thirteen exons spanning about 15 kilobases, in which the protein is encoded by exons 5-13. The "RING-finger" motif of Mel-18 protein that displays a significant evolutionary resemblance to other RING-finger nuclear proteins is encoded by exons 5 and 6. Exon 13 encodes a C-terminal proline/serine-rich domain that is homologous to some transactivator proteins. Sequence analysis of the 5'-flanking region revealed the presence of potential binding sites for transcription factors such as SP-1, NF-1, NF-kappa B and c-myc/max. At least two major cap sites and three minor cap sites were identified by S1 mapping and primer extension analysis. We propose that the mMel-18 gene is regulated by two different types of promoters, the CAAT-TATA box promoter and the GC-rich TATA-less promoter. The 2.4 kb DNA fragment of the 5'-flanking region exhibited constitutive promoter activity when transfected into L cells. By the in situ hybridization method, the mMel-18 gene was assigned to mouse chromosome 10C3.

Animals↗
PubMed1993

Ten-year experience in the use of double balloon catheter for kidney procurement from non-heart beating donors in cadaveric kidney transplantation.

One-hundred-and-twenty patients underwent first cadaveric kidney transplantation from the non-heart beating donors. All of the organs were procured with the use of double balloon catheter for in situ cooling. The mean warm ischemic time and cold ischemic time were 10.7 +/- 17.0 minutes and 18.9 +/- 11.4 hours, respectively. One- and 5-year graft survival rates were 85.0 and 72.7%, respectively. Among 120 recipients, 30 (25%) grafts functioned immediately (immediate function), 82 (68.3%) grafts functioned after varying length of oliguric periods (delayed function) and 8 (6.7%) grafts never functioned (non-function). The mean age of the donors in the group of immediate function (31.5 +/- 16.1 yr) was significantly lower than those of other two groups. The mean warm ischemic time in the group of immediate function (6.0 +/- 11.2 min) was significantly shorter than that of delayed function. However, there was no significant difference in donor hypotensive episode, types of preservation fluid and cold ischemic time between the groups. The conclusion is that the ultimate result of cadaveric kidney transplant from the non-heart beating donors with the use of double lumen catheter is acceptable despite a relatively high incidence of delayed graft function.

Adolescent↗
PubMed1993

[Measurement of the subretinal fluid volume using B-scan ultrasonography. Report 2. Measurement of the decrease rate of subretinal fluid in patients with rhegmatogenous retinal detachment].

I have previously reported the use of video-ultrasonography and an image computerized system to measure the volume of subretinal fluid (SRF). This measurement system was now used for 19 eyes with rhegmatogenous retinal detachment during absolute rest in bed for 24 hours and double patching. The mean age was 55 years (range, 18-69 years). The retinal detachment involved two quadrants or less of the retina in all eyes. The decrease rate of SRF was 0.051 +/- 0.033 microliter/mm2/hour (mean +/- standard deviation); 0.074 +/- 0.033 microliter/mm2/hour in 9 eyes in which the duration of retinal detachment was 14 days or less and 0.030 +/- 0.009 microliter/mm2/hour in 4 eyes in which the duration was 15 days or more. The rate was 0.032 +/- 0.009 microliter/mm2/hour in 3 eyes with atrophic holes. Three eyes with macular holes, which had retinal detachment underlying extensive staphyloma showed a rate of 0.028 +/- 0.022 microliter/mm2/hour. Though absolute rest in bed and double patching cannot completely block a transfer of fluid from vitreous to subretinal space via retinal break, the decrease rate of SRF appears to reflect the absorption of SRF across the retinal pigment epithelium.

Adolescent↗
PubMed1993

[Cerebral protection with selective cold blood cerebral perfusion by gravity during aortic arch reconstruction].

Selective cold blood cerebral perfusion by gravity using specially designed reservoir with a built-in heat exchanger was applied to 30 consecutive patients who required aortic arch reconstruction. Rectal and brain temperature during cerebral perfusion were maintained at 22 degrees C and 16 degrees C respectively. Patients were divided into two groups according to postoperative condition of consciousness. Twenty three patients had uneventful recovery of consciousness (Group-1), and 7 patients showed delayed recovery or disturbance of consciousness (Group-2). Age, sex, causes of aneurysm, rectal temperature and conditions of cerebral perfusate were not statistically significant in both groups. Selective cerebral perfusion time in Group-1 was 68 +/- 36 min and 85 +/- 31 min in Group-2 (statistically not significant). Extracorporeal circulation time in Group-2 (243 +/- 61 min) was significantly longer than in Group-1 (187 +/- 56 min) (p < 0.05). Five of seven patients (71%) in Group-2 were in shock pre- or early post-operative period contrary to 0% in Group-1 (p < 0.001). These results suggest that selective cold blood cerebral perfusion protects effectively the brain during aortic arch reconstruction in the patients without hemodynamic deterioration.

Adult↗
PubMed1992

Enalapril reduces the enhanced 1,2-diacylglycerol content and RNA synthesis in spontaneously hypertensive rat hearts before established hypertension.

There is evidence that cardiac hypertrophy in spontaneously hypertensive rats (SHR) occurs before the development of hypertension. 1,2-Diacylglycerol, which is thought to be a second messenger activating protein kinase C, is also produced in excess in SHR hearts at 4 weeks of age, before established hypertension. We determined myocardial 1,2-diacylglycerol content in SHR with and without prazosin and enalapril from 3 to 4 weeks of age. Hearts from untreated SHR had greater RNA and DNA synthesis and greater relative weights at 4 weeks of age than those from Wistar-Kyoto (WKY) rats. There was no difference in triglyceride content or phospholipid species between WKY rats and untreated SHR, except for a higher cholesterol content in SHR. Treatment of SHR with enalapril, but not prazosin, lowered not only 1,2-diacylglycerol content but also RNA synthesis to the levels of WKY rats. Moreover, fatty acids involved in 1,2-diacylglycerol were altered by enalapril despite the lack of a difference between WKY rats and untreated SHR. Prazosin did not have any effect on 1,2-diacylglycerol fatty acid composition. Enalapril may decrease cardiac hypertrophy in SHR by lowering myocardial 1,2-diacylglycerol production.

Animals↗