Biomedical subjects

H Aono

Publications and source records attributed to H Aono.

At least 55 records · Page 3Linked to original sources

PubMed1996

[Accurate placement of central venous catheters using right atrial electrocardiography].

We have evaluated the effectiveness of central venous catheter placement using right atrial electrocardiography (RAECG). Consecutive patients under general anesthesia (n = 42) who required a central venous catheter underwent RAECG-guided catheter insertion procedure via right internal jugular vein. Catheter tip position was verified by post procedure portable chest radiography. Forty of 42 catheter tips were placed above the superior vena cava-right atrial junction, and none of them had its associated complications. The average insertion depth of catheters was 16.4 cm. We also attempted to predict the optimal catheter insertion depth for each patient from the previous measurements of external landmarks, but it was found to be difficult to predict reliably. In this point of view, we should use RAECG technique to make sure the proper positioning of the catheter tip.

Aged↗

PubMed1996

Direct suppression of human synovial cell proliferation in vitro by salazosulfapyridine and bucillamine.

OBJECTIVE: The mechanism of disease modifying antirheumatic drugs (DMARD) is incompletely understood. We investigated in vitro the effect of DMARD such as bucillamine (Buc), salazosulfapyridine (SASP), and D-penicillamine (D-Pen) on the proliferation of human synovial cells in patients with rheumatoid arthritis (RA). METHODS: We evaluated the inhibitory effect of DMARD on [3H]-thymidine incorporation and cytokine production in synovial cells from patients with RA. Moreover, the expression of cytokine and protooncogene mRNA in synovial cells was determined by reverse transcription polymerase chain reaction methods. RESULTS: The proliferation of synovial cells and interleukin 1 beta (IL-1 beta) and interleukin 6 (IL-6) production of synovial cells were significantly inhibited by Buc and SASP in the concentration range of 1 to 100 microM in a dose dependent manner. In contrast D-Pen had no apparent effect at the same concentrations. Subsequently, the inhibitory effects of these compounds on transcriptional regulation of IL-1 beta, IL-6, and c-fos, which are well known to play an important role in synovial cell proliferation, were clarified. Overexpression of c-fos mRNA was inhibited by Buc and SASP. Moreover, the combination of low dose Buc and SASP inhibited synovial cell growth and transcriptional regulation of these mRNA. CONCLUSION: DMARD may have a direct inhibitory effect on rheumatoid synovial cell proliferation without the involvement of other cellular factors, which may be a mechanism of clinical remission induced by DMARD in patients with RA.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1996

Novel mechanisms of selective apoptosis in synovial T cells of patients with rheumatoid arthritis.

OBJECTIVE: To analyze whether T cells infiltrating the synovium of patients with rheumatoid arthritis (RA) express functional Fas antigen. METHODS: Mononuclear T cells, mainly from synovial tissues, synovial fluids (SF), and peripheral blood mononuclear cells (PBMC) from 14 patients with RA and 5 with osteoarthritis (OA), were treated with anti-Fas monoclonal antibody (Mab) (CH11) for 24 h in vitro. Cell viability and DNA fragmentation were examined. The expression of Fas antigen, Fas ligand, and T cell subpopulations was examined using flow cytometry and reverse transcription polymerase chain reaction. RESULTS: More than 50% of T cells from synovial tissue and SF of patients with RA underwent apoptosis, whereas no effect was observed in PBMC from RA or PBMC and synovial T cells from OA, suggesting that functional Fas antigens are specifically expressed on synovial T cells. Flow cytometric analysis demonstrated higher expression of Fas antigen in T cells from RA synovium than from PBMC. The T cell subpopulations susceptible to anti-Fas Mab were mainly CD45RO+ and CD4 or CD8 single positive T cells, indicating that activated mature T cells express functional Fas antigen. Fas ligand was overexpressed only in synovial nonadherent cells in RA at the level of mRNA, whereas T cells account for more than 60% of the total, but not in OA. CONCLUSION: These findings suggest the majority of activated T cells infiltrating the synovium express functional Fas antigen and Fas ligand specifically in patients with RA but not OA. This phenomenon may provide a clue to understanding the pathogenesis of RA.

Adult↗

PubMed1996

[Atherosclerosis and clinical examination: epidemiology of stroke and ischemic heart disease].

We discussed the risk factors for stroke and ischemic heart disease (IHD) as a main atherosclerotic disease. We showed that hypertension was the most principal risk factor for both cerebral hemorrhage and cerebral infarction, and the increase of total cholesterol (TCH) was inversely related with the incidence of cerebral hemorrhage. Many of the cerebral infarctions occurred where a large number of the cerebral hemorrhages did. We indicated that the mechanism of occurrence was different between stroke and IHD. In Japan, TCH has been recognized as a risk factor for IHD as same as western countries, but there are not many IHD. The mean of TCH was lower before one or two decade. But, it has increased in the last decade, and recently is nearing the level of American people in the thirties and forties. Death statistics of IHD became more accurate in Japan by reason for revision of the death certificate form from ICD-9 to ICD-10. The recognition of IHD death statistics will be changed. Incidence of stroke has been decreasing because of the decrease of hypertension. However, we will have to reconsider a preventive measure of IHD.

Adult↗

PubMed1995

Oligoclonal proliferation of human T-cell leukemia virus type I infected lymphocytes in lesions of virus-induced arthropathy.

To investigate the pathogenesis of human T-cell leukemia virus type I associated arthropathy, the mode of proviral integration in the pathological lesions was analyzed using ligation-mediated polymerase chain reaction. Peripheral blood mononuclear cells (PBMC) of these patients possessed multiple dominant clones of the virus-infected cells. On the other hand, synovial fluid cells of the affected joints exhibited fewer dominant clones even though the copy numbers of the provirus were comparable to those of PBMC. Thus, restricted HTLV-I infected T cell clones may proliferate and expand in the lesions.

Aged↗

PubMed1995

Apoptosis and functional Fas antigen in rheumatoid arthritis synoviocytes.

OBJECTIVE: To determine whether apoptosis occurs in rheumatoid arthritis (RA) synoviocytes, and if this phenomenon is dependent on the Fas/Apo-1 pathway. METHODS: Apoptotic change in vivo was examined in RA synovial cells by several standard methods. The ability of cells to undergo Fas-induced apoptosis was determined in vitro. RESULTS: Typical apoptotic change was demonstrated in RA synovial cells by each method. Anti-Fas antibody induced apoptotic synovial cell death in vitro. CONCLUSION: This is the first reported study to demonstrate apoptosis in RA synovial cells. The findings indicate that rheumatoid synoviocytes undergo Fas-mediated apoptosis.

Antibodies↗

PubMed1995

[Usefulness of rapid detection of plasma insulin levels during resection of insulinoma].

Insulinoma is one of the causes of hypoglycemia and can be cured by surgery. Using the enzyme immunoassay kit (ERUMOTEC INSULIN, Mochida Pharmacy Co.), immunoreactive insulin (IRI) can be measured within one hour. Curative operation was confirmed by normalized IRI level. A 58-year-old man had an episode of loss of consciousness. His blood glucose was below, and his IRI was above, normal. These and other examinations revealed that he was suffering from insulinoma. Tumor resection under general anesthesia was scheduled. Glucose was continuously administered intravenously to prevent hypoglycemia until the end of tumor resection. Frequent blood glucose measurement showed that he had no hypoglycemic episodes. Using the enzyme immunoassay kit, IRI was found to be 704 microU.ml-1 during manipulation of the tumor. At 30 minutes after the tumor resection, it decreased to 9.8 microU.ml-1 (within normal ranges). These data suggested that the operation was curative and that no further hypoglycemic attacks by remnant insulinomas would be anticipated.

Anesthesia, General↗

PubMed1995

Toxicity study of the angiotensin converting enzyme inhibitor rentiapril in rats.

A three-months toxicity study of an angiotensin converting enzyme (ACE) inhibitor, rentiapril (CAS 80830-42-8), was performed in Sprague-Dawley rats by oral administration. The dose levels of 0, 30, 125, 500 and 1000 mg/kg were tested in both sexes, in which each experimental group comprised 10 rats. Another ACE inhibitor, captopril, was used as a reference compound. Rentiapril at the highest dose of 1000 mg/kg caused low food consumption and death of some animals with signs of bloody feces and anemia. In males and females receiving 500 and 1000 mg/kg, there were low body weight gain, increases in water intake, urine volume and serum BUN level, and decreases in levels of various erythrocytic parameters. Kidney weight was increased dose-dependently in both sexes. Histopathologically, renal changes in the 500 and 1000 mg/kg groups consisted of proximal tubular degeneration, juxtaglomerular cell hyperplasia and interstitial cell infiltration. Similar, but mild, changes in proximal tubules were present in the female 125 mg/kg group. Dead animals from the highest dose groups further showed gastrointestinal hemorrhagic erosion and/or ulcer, decreased bone marrow erythropoiesis and hepatocytic vacuolar degeneration. There was no pathological alteration in rats from other rentiapril-treated groups, as well as in controls. These results indicate that the no-effect dose of rentiapril in rats by three months oral administration is 30 mg/kg in female and 125 mg/kg in male, and suggest that, like other ACE-inhibitors, this compound also has a toxic potential to affect renal tissues.

3-Mercaptopropionic Acid↗

PubMed1994

Establishment and characterization of synovial cell clones with integrated human T-cell leukemia virus type-I.

Human T cell leukemia virus type-I (HTLV-I)-integrated synovial cell clones (SCCs) were established from four HTLV-I-infected patients with chronic proliferative arthropathy. Extracted DNAs of these SCCs were examined for the existence of HTLV-I proviral DNA. Electron microscopic analysis and immunohistochemical staining were also performed to examine the nature of the HTLV-I integrated SCCs. SCCs derived from all four patients consisted of either HTLV-I integrated or nonintegrated cells. HTLV-I integrated SCCs also produced viral messenger RNA which was detected by reverse transcriptase-polymerase chain reaction as well as viral protein which was detected by immunohistochemical staining. Phenotypically, these SCCs containing HTLV-I proviral DNA were shown to be all cell types as observed by electron microscopic analysis and immunohistochemical analysis. Moreover, expression of HTLV-I glycoprotein was greater in SCCs with a monocyte marker. These findings suggest that SCCs harboring HTLV-I have an important role in synovial hyperplasia.

Aged↗

PubMed1994

[Perioperative management of a patient with myotonic dystrophy developing the cardiac symptoms initially prior to the neuromuscular symptoms].

The authors anesthetized a 48-year-old woman with endometrial cancer and a large ovarian cyst. She developed cardiac failure initially followed by the sick sinus syndrome and A-V block from hypertrophic cardiomyopathy, prior to neuromuscular symptoms. Epidural anesthesia assisted by general anesthesia was carried out safely without intravenous administration of any muscle relaxants. From this experience, it is considered that epidural anesthesia assisted with some other proper methods is suitable for surgery of lower abdomen.

Anesthesia, Epidural↗

PubMed1993

Radial and median nerve conduction velocities in workers exposed to lead, copper, and zinc: a follow-up study for 2 years.

To evaluate the interactive effects of lead, zinc, and copper on the peripheral nervous system in man, we measured maximal motor and sensory conduction velocities (MCV and SCV) in the distal radial and median nerves in 19 gun metal foundry workers with asymptomatic increased absorption of these metals twice at a 12-month interval. The workers' initial blood lead (BPb) concentrations ranged from 16 to 64 (mean, 42) micrograms/dl. The principal findings in the present study indicated that (1) radial and median nerve conduction velocities were significantly slowed in the gun metal foundry workers; (2) indicators of lead absorption were inversely related to radial nerve conduction velocities, whereas indicators of copper and zinc absorption were positively correlated with the radial and median nerve conduction velocities; and (3) yearly changes in MCV in the radial nerve and in SCV in the median nerve were positively correlated with the changes in indicators of copper and zinc absorption. These findings suggest that zinc and copper antagonize the subclinical neurologic effects of lead. Also, the radial and median nerve conduction velocities provide important indicators of subclinical lead toxicity.

Adolescent↗

PubMed1993

Overgrowth of human synovial cells driven by the human T cell leukemia virus type I tax gene.

One of the salient pathological features of rheumatoid arthritis is synovial cell proliferation with bone erosion. Despite extensive investigation, the factors essential for synovial cell proliferation remain to be identified. Recent studies suggest that human T cell leukemia virus type I (HTLV-I) may play an important role in synovial overgrowth observed in patients with one type of chronic inflammatory synovitis. In order to confirm and extend these observations, we have established synovial cell clones (SCCs) from three HTLV-I carriers who demonstrated synovial overgrowth but were otherwise asymptomatic. HTLV-I proviral DNA randomly integrated into the cellular genome was present in 20-30% of SCCs. The SCCs carrying HTLV-I proviral DNA and expressing the tax gene exhibited high levels of proliferative potential. HTLV-I was found to function as a transcriptional trans-activator in these SCCs. Moreover, transfection of the tax expression plasmid into SCCs resulted in the same phenotype of increased proliferation and cytokine expression as exhibited by HTLV-I provirus-carrying and tax-expressing SCCs. These data suggest that tax plays a critical role not only in leukemogenesis but also in synovial overgrowth in humans.

Arthritis↗

PubMed1991

[The CO2 absorption capacity and color indication of a newly developed soda lime (Wakolime)].

The CO2 absorption capacity and the color change of ethyl violet (color indicator) of Wakolime A (newer type). Wakolime (older type), and Sorb 800 were studied under the clinical anesthetic condition. A two chamber canister was filled with soda lime and anesthetic gas flowed upward through the canister at the rate of 4 ml.min-1. The wall temperature of each chamber was measured with surface temperature sensing device. After 30 hours of use, the colored soda lime in the first chamber was examined with a color analyzer. The change of wall temperature indicated that the CO2 absorption capacity of Sorb 800 was the largest and that of Wakolime was the smallest among the three. The indicator color of both Wakolime A and Sorb 800 was clearer and of more vivid violet than that of Wakolime, which was dull and grayish. These results indicated that Wakolime A is superior in the CO2 absorption capacity and color indication to Wakolime.

Absorption↗

PubMed1990

Central and peripheral nervous system effects of hand-arm vibrating tool operation. A study of brainstem auditory-evoked potential and peripheral nerve conduction.

To examine the effects of hand-arm vibrating tool operation on the central and peripheral nervous system, the brainstem auditory-evoked potential (BAEP), median nerve conduction velocity and hearing level were measured in twelve chain saw operators (6 operators had a history of white finger attack) and in eight brush saw operators (none had a history of the attack). Control subjects, matched to each chain saw and brush saw operator by sex and age, were selected randomly from healthy adults without otitis, deafness and tinnitus. The I-V interpeak latency (conduction from cochlear nerve to brainstem) and V peak latency of BAEP were significantly prolonged in chain saw operators; the I-V interpeak latency was significantly correlated with working years in brush saw operators. The median nerve conduction velocity was significantly slowed in both chain saw and brush saw operators. Moderate hearing loss was observed in the two groups. It is suggested that vibrating tool operation, i.e. the combined stressors of local vibration, noise, climate and heavy work, affected not only the peripheral nervous system but also the brainstem portion of the auditory pathway; the brainstem effect, if any, is less advanced than the peripheral nervous system effect of local vibration.

Adult↗

PubMed1989

Agonist activity of a novel compound, 1-[3-(3,4-methylenedioxyphenoxy)propyl]-4-phenyl piperazine (BP-554), at central 5-HT1A receptors.

We used an in vitro radioligand receptor binding assay with rat cerebral cortex, hippocampus and striatum membrane preparations to show that 1-[3-(3,4-methylenedioxyphenoxy)propyl]-4-phenyl piperazine (BP-554) had much higher affinity for 5-HT1A recognition sites than for 5-HT1-non-A, 5-HT2, benzodiazepine, dopamine D-2 and alpha 2-adrenergic recognition sites. The compound inhibited the activity of forskolin-stimulated adenylate cyclase in rat hippocampal membranes. Intraperitoneal injection of BP-554 to mice decreased the concentration of only 5-hydroxy-indoleacetic acid of the amines and their metabolites in the brain and decreased the accumulation of 5-hydroxytryptophan in the brain after decarboxylase inhibition by 3-hydroxybenzylhydrazine. Furthermore, the administration of BP-554 caused hypothermia and increased serum corticosterone levels in mice. The observed effects of BP-554 were similar to those of 8-hydroxy-2-(di-n-propylamino)tetralin. These results suggest that BP-554 acts as a selective 5-HT1A receptor agonist in vivo.

8-Hydroxy-2-(di-n-propylamino)tetralin↗

PubMed1989

Effects of water restriction and water loading on daily urinary excretion of heavy metals and organic substances in metal workers.

The effects of urinary volume on daily urinary excretion of seven heavy metals and four organic substances were examined in relation to the changes in their plasma and erythrocyte concentrations and urinary creatinine excretion in 19 metal workers. The examination was conducted under the conditions of water restriction and loading for six days. The major findings were as follows: (1) urinary excretion of all heavy metals and organic substances except mercury, together with creatinine excretion, significantly decreased under the water restrictive condition whereas under the water loading condition their excretion significantly increased and (2) daily variations in urinary excretion of lead, cadmium, chromium, copper, hippuric acid, delta-aminolaevulinic acid, and coproporphyrin did not differ significantly from the variation in urinary excretion of creatinine (profile analysis, p greater than 0.05). It is suggested that glomerular filtration is the major factor determining renal excretory mechanisms of the four heavy metals and three organic substances examined.

Adult↗

PubMed1988

Circadian rhythms in the urinary excretion of heavy metals and organic substances in metal workers in relation to renal excretory mechanism: profile analysis.

Circadian rhythms in the urinary excretion of eleven heavy metals and organic substances were examined under free, water-restrictive and water-loading conditions for 6 d (2 d for each of the three conditions) in twenty metal workers exposed to lead, zinc and copper. Circadian rhythms were found for all heavy metals and organic substances as well as for urinary flow (UF) rate, creatinine (Cn) and total urinary solutes (TUS). The Cn rhythm was significantly unparallel to the UF rhythm under the water-loading condition, indicating that the two rhythms were essentially different from each other. Circadian rhythms of the eleven urinary substances were then related to the Cn and UF rhythms, using profile analysis. The results indicated that the rhythms in the manganese, chromium, copper and beta-2-microglobulin excretion depend on the Cn rhythm, i.e. the rhythm of glomerular filtration; the rhythms in the hippuric acid, delta-aminolevulinic acid and TUS excretion are on the UF rhythm, i.e. the rhythm of reabsorption by the distal tubule and collecting duct. On the other hand, the rhythms in the lead, inorganic mercury, cadmium, zinc and coproporphyrin excretion were considered as reflecting complex renal excretory mechanisms.

Adult↗

PubMed1988

A gradient of responsiveness to the growth-promoting activity of ZPA (zone of polarizing activity) in the chick limb bud.

Limb bud mesoderm of stage 22-23 embryos was dissected into four pieces along the anteroposterior axis and dissociated cells of each region were separately cultured under various conditions. When the cells were cultured in medium containing 0.1% fetal calf serum (serum-poor medium) only a slight increase in cell number occurred in the cultures of all four regions. However, when the cells were cultured in medium containing 10% FCS, only cells of two central regions proliferated rapidly, and no growth promotion was observed in cells in the most anterior and posterior regions. Using the serum-poor medium, we examined the growth-promoting effects of cocultured limb bud fragments and of some growth factors on the cells of four regions. Anterior, distal, and proximal fragments promoted cell proliferation and their promotive effect on the cells of each region was equal. On the other hand, posterior fragments (containing ZPA) showed stronger promotive effects on preaxial cells than on postaxial cells. For comparison with the growth-promotive effect of the posterior fragment, fibroblast growth factor (FGF), epidermal growth factor (EGF), insulin, and retinoic acid were tested in cell culture. FGF showed position-dependent growth promotion, while EGF and insulin promoted growth in the cells of all four regions to a similar degree. Retinoic acid showed no effect on cell growth at low concentrations, and was rather toxic at high concentrations. These results suggest that the cells of the posterior region secrete an FGF-like growth factor(s), which controls normal limb development and experimental duplicate formation.

Animals↗