Search PubMed⌕ Search

Biomedical subjects

H Uchiyama

Publications and source records attributed to H Uchiyama.

At least 163 records · Page 9Linked to original sources
PubMed1992

Isolation and characterization of cesium-accumulating bacteria.

Cesium-accumulating bacteria, strains CS98 and CS402, were isolated from soil by a radioactive autoradiographic method using 137Cs. These strains displayed the rod-coccus growth cycle and contained mesodiaminopimelic acid, mycolic acids, and tuberculostearic acids. The major menaquinone of CS98 was MK-8(H2). On the basis of these characteristics, strain CS98 was identified as Rhodococcus erythropolis and strain CS402 was classified in the genus Rhodococcus. The maximum values of cesium removal efficiencies in the liquid culture containing 10 mumol of cesium per liter for strains CS98 and CS402 were 90 and 47%, respectively. The maximum cesium contents in strains CS98 and CS402 were 52.0 and 18.8 mumol/g (dry weight) of cells, respectively. Maximum values of cesium concentration factors for strains CS98 and CS402 were 3.5 x 10(4) and 3.6 x 10(3), respectively.

Autoradiography↗
PubMed1992

Role of heterotrophic bacteria in complete mineralization of trichloroethylene by Methylocystis sp. strain M.

Biodegradation experiments with radioactively labeled trichloroethylene showed that 32% of the radioactive carbon was converted to glyoxylic acid, dichloroacetic acid and trichloroacetic acid and that the same percentage was converted to CO2 and CO after 140 h of incubation by a pure culture of a type II methane-utilizing bacterium, Methylocystis sp. strain M, isolated from a mixed culture, MU-81, in our laboratory. In contrast, these water-soluble (14C)trichloroethylene degradation products were completely or partially degraded further and converted to CO2 by the MU-81 mixed culture. This phenomenon was attributed to the presence of a heterotrophic bacterium (strain DA4), which was identified as Xanthobacter autotrophicus, in the MU-81 culture. The results indicate that the heterotrophic bacteria play an important role in complete trichloroethylene degradation by methanotrophs.

Biodegradation, Environmental↗
PubMed1992

Changes in retinal projections and ganglion cell morphology after unilateral enucleation in the common carp.

Changes in retinal projections and ganglion cell morphology were studied in one-eyed individuals of the common carp, Cyprinus carpio, which were enucleated at a juvenile stage (within 6 months after hatching) and kept for 18 months after the operation. Gross examination of the brains showed a marked atrophy of the contralateral optic tectum and a fine attenuated optic tract ipsilateral to the remaining eye. All retinal recipient areas were bilateral, but numerous projections were heavier contralaterally. Terminal branches in the recipient areas showed more complex patterns with tortuous courses and larger numbers of terminal swellings than in normal animals. Total numbers and distribution patterns of ganglion cells in Nissl-stained retinal whole mounts of one-eyed carp were compared with those in normal carp. The total number of ganglion cells was estimated to be 14 x 10(4)-18 x 10(4) in both one-eyed and normal carp. No difference was observed in isodensity maps and soma area histograms between one-eyed and normal carp. Following injections of horseradish peroxidase and nuclear yellow into the optic tectum of each side, three different types of tectal projecting ganglion cells were observed in the remaining retina: contralaterally projecting (CP) cells, ipsilaterally projecting (IP) cells, and bilaterally projecting (BP) cells. The distribution pattern of CP and BP cells in the retina suggested normal retinotopy. However, BP cells were found in a more restricted zone within the CP cell distribution area. The IP cells had a tendency to be scattered sparsely in a wide central area and a dorsal quadrant of the retina. No IP or BP cells were found in the peripheral retina. The time course and morphological changes in axons of these cells are discussed.

Animals↗
PubMed1992

Importance of coronary artery spasm in alcohol-related unexplained syncope.

To examine the role of coronary artery spasm in patients with syncope after alcohol ingestion, we performed an intracoronary ergonovine provocation test in 7 male patients (39 to 73 years old, mean 54 years) with alcohol-related syncope which remained unexplained despite noninvasive cardiovascular and neurological examinations. No patients had structural heart disease or significant coronary artery stenosis. Ergonovine was continuously infused into each coronary artery at a rate of 10 micrograms/min for up to 5 min. Coronary artery spasm with ST-segment elevation was induced in 4 of 7 patients. Chest pain before syncope or history of chest pain were not present in 3 of 4 patients with a positive ergonovine test. Multivessel coronary artery spasm was induced in 3 patients. One patient presented with triple vessel coronary artery spasm progressing to near syncope as a result of profound hypotension and ventricular tachycardia during provocation. Coronary artery spasm was promptly relieved by intracoronary isosorbide dinitrate infusion. All patients with a positive ergonovine test were treated with calcium antagonist and did not experience syncope during follow-up. These results suggest that coronary artery spasm is one of the important causes of syncope after alcohol ingestion.

Adult↗
PubMed1992

Acute hemodynamics of pimobendan in chronic heart failure. A comparative crossover study of captopril and pimobendan.

Acute hemodynamics of pimobendan were compared to captopril in a crossover trial in patients with chronic heart failure (NYHA II-III). Heart failure had been stabilized by conventional therapy with diuretics and digitalis for more than 2 weeks. Patients receiving vasodilators were excluded. The hemodynamics were analyzed using a Swan-Ganz catheter at the bedside during drug administration. Following an intravenous injection of 2.5 mg of pimobendan, there was a significant increase in heart rate and decrease in mean pulmonary artery pressure, total pulmonary resistance, mean arterial pressure, systemic vascular resistance and mean right atrial pressure 2 hours after the injection. Captopril (12.5 mg, orally) significantly decreased mean arterial pressure, systemic vascular resistance and double product 2 hours after administration. In this study, the inotropic effect was evaluated through the relation between the stroke volume index and diastolic pulmonary artery pressure, and also between the stroke volume index and mean arterial pressure. Although decreases of diastolic pulmonary artery pressure and mean arterial pressure were seen with both drugs, the differences in stroke volume index were not significant. In comparison with captopril, the acute hemodynamics of pimobendan are characterized as follows: 1) the systemic arteriovasodilating effects of the two drugs were equal, 2) the pulmonary arteriovasodilating effect of pimobendan was marked, 3) a venodilating effect, documented through a decrease of mean right atrial pressure, was seen only with pimobendan. This study concluded that pimobendan is a stronger arterio-venodilator than captopril.

Aged↗
PubMed1992

[Effects of prednisolone farnesylate (PNF) gel on skin and ocular mucosa].

Various tests for irritation, phototoxicity, contact sensitivity and photocontact sensitivity of PNF gel were conducted. The results were as follows. 1) In the primary dermal irritation test and trypan blue test, slight erythema was noted in the rabbits treated with 0.8 and 1.6% PNF gel, although similar reaction occurred in those treated with the base. 2) In the test for the primary irritation to the ocular mucosa, severe irritant reactions were caused by 0.8 and 1.6% PNF gel and its base. However these reactions disappeared 7 days after irritation. 3) In the phototoxicity test and contact sensitivity test, no positive reactions were detected by 0.8 and 1.6% PNF gel. On the other hand, in the photocontact sensitivity test, positive reaction were noted in the guinea pig treated with 0.8 and 1.6% PNF gel and its base.

Animals↗
PubMed1992

[A case of small cell lung cancer occurring in a patient with pulmonary sarcoidosis].

A 62-year-old man was diagnosed as having sarcoidosis on the basis of uveitis, and the findings of bronchial alveolar lavage and transbronchial lung biopsy, in April 1988. He was admitted to hospital in September 1990, because of left hemiplegia. The chest X-ray film on admission revealed a new mass shadow in the left S6 and some increase of nodular shadows in both lung fields. A bronchial biopsy from the left B6 bronchus revealed small cell lung cancer. Although he was treated with whole brain irradiation and combination chemotherapy, he died of respiratory failure after three months. Speculations about the association between sarcoidosis and lung cancer have been made, but the mechanism is not understood, and their co-existence in the same patient is rare.

Brain Neoplasms↗
PubMed1992

[Acute hemodynamic effects of pimobendan and captopril: a comparative study in the same patients with chronic heart failure].

In this study, the acute hemodynamic effects of pimobendan (2.5 mg), a new drug, was compared with that of captopril (12.5 mg) in the same 8 patients with chronic heart failure (NYHA class II-III); 3 with dilated cardiomyopathy and 5 with regurgitant valvular heart disease. The hemodynamics were serially assessed before and after drug administration for at most 6 hours. Pimobendan reduced mean blood pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, right atrial pressure, total systemic vascular resistance, and total pulmonary vascular resistance but it increased heart rate. By contrast, captopril reduced mean blood pressure and double product. No significant changes were noted in the cardiac index, stroke volume index, AV-O2 difference or the arterial oxygen pressure between the 2 drugs. In conclusion, pimobendan seems to function as a strong arterio-veno-dilator rather than as an inotropic agent in patients with chronic heart failure.

Aged↗
PubMed1991

Presence of activin (erythroid differentiation factor) in unfertilized eggs and blastulae of Xenopus laevis.

Activin A, a member of the transforming growth factor beta superfamily, has recently been found to have potent mesoderm-inducing activity on isolated early Xenopus animal-cap cells. We measured the activin activity of the Xenopus egg extract by using an erythroid-differentiating test with Friend leukemia cells. The results showed that an activin homologue is, indeed, contained in unfertilized eggs and blastulae of Xenopus laevis in a considerable amount. This activity was eluted at the same retention time as human activin A when fractionated by reversed-phase HPLC. Furthermore, the fraction containing erythroid-differentiating factor activity had mesoderm-inducing activity on Xenopus animal-cap cells. The mesoderm-inducing activity of this fraction was suppressed when coincubated with follistatin, an activin-binding protein. These results suggest that an endogenous activin may be a natural mesoderm-inducing factor acting in Xenopus embryogenesis.

Activins↗
PubMed1991

Protein kinase C in tumoricidal activation of mouse macrophage cell lines.

A potential role of protein kinase C (PKC) in lipopolysaccharide- (LPS-) induced tumoricidal activation of macrophages was investigated by using two mouse macrophage cell lines (P388D1 and J774). J774 cells are stimulated by LPS to kill target P815 mastocytoma cells, whereas P388D1 cells fail to develop such an ability. Pretreatment of J774 cells with H-7 or phorbol myristate acetate resulted in a significant inhibition of LPS-induced cytotoxicity, whereas pretreatment with H-8, ML-7, HA1004, or W-7 did not. Since these results suggested a critical role of PKC in the activation process, the properties of PKC in the two cell lines were compared. Western blotting with rabbit antiserum specific for the PKC beta regulatory domain allowed detection of a protein of 79 kilodaltons (kDa) in the detergent lysates of both cell lines that were not stimulated by LPS. However, LPS treatment resulted in the appearance of a second protein of 40 kDa only in J774 cells and not in P388D1 cells. Furthermore, two forms of protein kinase (one basic and the other acidic) were identified in the cytosol of J774 cells by HPLC on DEAE-5PW, whereas only the basic form was found in P388D1 cells. On the basis of the response of the basic and acidic form protein kinases to phosphatidylserine (PS), diolein, and Ca2+, the basic form was found to contain both regulatory and catalytic domains of PKC, whereas the acidic form was suggested to represent the PKC catalytic domain.(ABSTRACT TRUNCATED AT 250 WORDS)

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1991

Soluble thrombomodulin antigen in conditioned medium is increased by damage of endothelial cells.

Thrombomodulin (TM) exists not only in endothelial cells but also in circulating plasma as soluble heterogeneous fragments. A release mechanism of soluble TM antigen from endothelial cells was investigated. Cultured human umbilical vein endothelial cells released about 0.6% of total cellular TM antigen into conditioned medium during 24 h. The release of TM antigen was not influenced by addition of various concentrations (0.01-5.0 microM) of monensin, which inhibits intracellular transport of secretory proteins, though the secretion of plasminogen activator inhibitor-1 from the cells was inhibited. The release of TM antigen was not increased when total cellular TM level increased 1.3- or 1.4-fold relative to control cells after stimulation with 0.1-1.0 U/ml thrombin or 3 mM dibutyryl cAMP, respectively. Exposure of endothelial cells for 6 h to mixture of 1 microM N-formyl-methionyl-leucyl-phenylalanine (FMLP) and 100 ng/ml lipopolysaccharide (LPS) decreased cellular TM level by 30% relative to control cells without increase in the TM release. The FMLP and LPS-stimulated leukocyte treatment of the cells increased the release of TM antigens into the medium in a time-dependent manner and the increased release of TM antigen paralleled the extent of cell damage as measured by 51Cr release. Hydrogen peroxide treatment of the cells increased the release of TM antigens into the medium in a time- and concentration-dependent manner. The increased release of TM antigen by hydrogen peroxide also paralleled the extent of cell damage.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Western↗
PubMed1991

Changes in the structure and biological property of N----O sulfate-transferred, N-resulfated heparin.

The N----O sulfate transfer of heparin has been investigated as an approach to chemical 3-O-sulfation of the D-glucosamine residues in heparin. The pyridinium salt of porcine heparin was heated at 90 degrees C in solid state for 90 min (in vacuo over P2O5) to effect the transfer of the N-sulfate groups to the HO groups in the polysaccharide, followed by N-resulfation. The product (N----O sulfate-transferred, N-resulfated heparin (ST heparin] was depolymerized with HONO to generate a mixture of di- and higher oligosaccharides. The borohydride-reduced oligosaccharides were separated on Bio-Gel P-4 and DEAE-Sephacel. The disaccharide trisulfate fraction (10.4% yield) was found to be a mixture of nearly equal amounts of IdoA(2-SO4)-AManR(3,6-diSO4) and IdoA(2,3-diSO4)-AManR(6-SO4), where IdoA represents L-iduronic acid and AManR represents the alditol formed by reduction of 2,5-anhydro-D-mannose with NaBH4. Chemical and NMR spectroscopic analyses revealed that the N----O sulfate transfer proceeded preferentially at HO-3 positions in both 6-O-sulfo-D-glucosamine and 2-O-sulfo-L-iduronic acid residues. Chromatography on antithrombin III-Sepharose gel indicated that the structural change involved in ST heparin resulted in an obvious increase in the ability to bind antithrombin III. Biological examination also indicated that this structural change resulted in moderate increases in all the activities (blood anti-clotting, anti-Factor IIa, and anti-Factor Xa) and in the strength of intrinsic fluorescence of antithrombin III.

Animals↗
PubMed1991

The vegetalizing factor from chicken embryos: its EDF (activin A)-like activity.

The erythroid differentiation capacity of the HPLC-purified mesoderm- and endoderm-inducing vegetalizing factor from chicken embryos and of recombinant erythroid differentiation factor (EDF = activin A), an evolutionary highly conserved member of the TGF-beta protein superfamily have been compared. Both factors stimulate the synthesis of hemoglobin in erythroleukemia cells in the same concentration range. The EDF-activity of the mesoderm-inducing HPLC-fractions is inhibited by follistatin, an EDF-binding protein. The factor induces in ectoderm of Triturus taeniatus all kinds of mesodermal organs. The wide spectrum of organs is very likely to be induced by secondary interactions. At higher concentration (15 ng/ml), notochord- and endoderm-like tissues are induced in a high percentage.

Activins↗
PubMed1991

Comparative study of Vibrio cholerae non-O1 isolated from 2 rivers according to antibiotics and metals susceptibility.

Vibrio cholerae non-O1 was isolated at six locations on each of two different rivers in 1984 and 1985. A study of the strains isolated from these rivers according to antibiotic and metal susceptibility and the incidence of resistant strains produced the following results. 1) Tests to determine susceptibility to eight antibiotics (chloramphenicol, tetracycline, streptomycin, kanamycin, ampicillin, gentamicin, nalidixic acid and polymyxin-B) indicated that there was virtually no difference in the susceptibility of strains isolated from the two rivers. Of the 115 environmental strains, 81 (70.4%) showed resistance to one or more drugs. However, no strains were resistant to gentamicin. There was considerable variation in the concentration of susceptibility to polymyxin-B, and for this reason it was difficult to determine the resistance concentration. 2) 64.3% (74/115) of the strains isolated from the two rivers showed ampicillin resistance and produced beta-lactamase. 3) 67.9% (55/81) of all resistant strains were resistant only to ampicillin, while 16.0% (13/81) were resistant to ampicillin and nalidixic acid. The rate of resistance to these substances was higher than to the other drugs. 4) The incidence of resistant strains differed according to environmental conditions along the two rivers. These variations appear to reflect the influence of environmental conditions in the catchment areas. 5) There was no metallic contamination in either the Sagami River, which has good water quality, or the Sakai River, which is heavily polluted. This meant that there was no variation in the metal susceptibility of the isolated strains according to differences in the degree of water pollution. Furthermore, none of the strains showed resistance to metals.

Anti-Bacterial Agents↗
PubMed1991

[Study of IgE.IgG4 antibodies on eczema in infants. II. Clinical characteristics of infants with egg white.RAST 4+].

The author made an assessment in his first report, regarding relationship to the degree of skin involvement. As a result, it was suggested that the extent of eczema is a good index for determining the severity of the allergy and also that the severity of the allergy early in the infancy has a good correlation with egg white.specific IgE antibody. Therefore, an assessment had been made this time regarding the clinical characteristics of 32 infants who have strong reactions (egg white.RAST 4+) to egg white. The results were as follows; 1. All the infants with egg white.RAST 4+ had a systemic eczema, and their IgE antibodies showed high values of 445.6 +/- 626.9 IU/ml. 2. There were many cases with positive multiple allergens. Particularly, all the infants with egg white.RAST 1+ - 2+ were negative to rice and wheat, while 7 cases positive RAST score to rice and 9 cases to wheat were seen out of the 32 who showed the RAST 4+ to egg.white early in the infancy (rice; p less than 0.02 and wheat; p less than 0.01). 3. If the growth curves of the group from which egg and milk were completely eliminated are compared with the curves of the healthy infants, the height and head circumference were entirely in the normal range while the weight and Kaup index had a trend of being a little low, though they were within the normal range. 4. Regarding family history of allergies, past histories of atopic dermatitis on the mother's side were observed at a high rate.

Dermatitis, Atopic↗