PubMed Health⌕ Search

Biomedical subjects

T Ueda

Publications and source records attributed to T Ueda.

At least 1,261 records · Page 70Linked to original sources

Comparison of macroscopic, postmortem, angiographic and two-dimensional echocardiographic findings of coronary aneurysms in children with Kawasaki disease.

To assess why the results of 2-dimensional echocardiography (2-D echo) for diagnosis of coronary aneurysm in patients with Kawasaki disease differed from those of cineangiography, the macroscopic, postmortem, angiographic and 2-D echocardiographic findings of 8 autopsied hearts of infants and children with Kawasaki disease were compared. Postmortem angiography and 2-D echo yielded similar results in aneurysms in which there was no thrombus, organization or marked thickening of the arterial wall. However, in aneurysms with complete or incomplete occlusion of the dilated cavity due to thrombi, organization or marked thickening of arterial wall, angiographic results reflected only the free cavity of the coronary aneurysm, but could not detect the original aneurysm. Two-dimensional echocardiography disclosed an echo-free space representing the original aneurysm, in which some materials, suggesting thrombi or organization, were found. However, it did not reveal whether the aneurysm was occlusive. This finding indicates that the discrepancies between the results of cineangiography and 2-D echo are attributable to the formation of large thrombi, organization or marked thickening of the arterial wall in the aneurysmal cavity. It is clinically important to know these limitations of angiography and 2-D echo.

Angiocardiography↗

Purification and characterization of Ca2+/H+ antiporter from Bacillus subtilis.

Ca2+ was accumulated in inside-out membrane vesicles of Bacillus subtilis when NADH was used as an energy source. A delta pH (acid interior) could also drive Ca2+ accumulation in the membrane vesicles and the accumulation was inhibited by carbonylcyanide p-trifluoromethoxyphenylhydrazone and nigericin plus K+. These results indicate the presence of a Ca2+/H+ antiporter (exchanger) in this organism. The antiporter was isolated and purified to homogeneity from the membrane proteins by chromatography on hydroxyapatite, diethylaminoethyl(DEAE)-Toyopearl 650 M and butyl-Toyopearl 650 M. The purified antiporter has a molecular mass of about 45 000 daltons and an isoelectric point of 5.0. The fluorescence quenching of a cyanine dye (3,3'-dipropylthiodicarbocyanine iodide [diS-C3-(5)] during Ca2+ accumulation in proteoliposomes by the purified antiporter showed the generation of a membrane potential (interior negative) suggesting a H+/Ca2+ stoichiometry above 2 in the transport. This was also supported by the result that the K+-diffusion potential, interior positive, stimulated the Ca2+ uptake in the presence of a delta pH. The apparent Km for Ca2+ of the antiporter was about 40 microM and La3+ inhibited the transport. Amino acid analysis of the purified antiporter indicated the presence of large amounts of glutamic and aspartic acids and small amounts of histidine, lysine and arginine. This is consistent with the low isoelectric point (about 5.0) of the protein.

Amino Acids↗

Orientation of synaptic plasma membrane vesicles containing calcium pump and sodium-calcium exchange activities.

Sidedness of synaptic plasma membrane vesicles isolated from brain synaptosomes has been assessed by two distinct experimental approaches: first, analysis of (Na+ + K+)-ATPase, Mg2+-ATPase, and (Ca2+ + Mg2+)-ATPase activities before and after permeabilization of vesicles; second, analysis of Ca2+ fluxes via the Na+/Ca2+ exchanger, before and after modification of an imposed Na+ gradient by penetrating or nonpenetrating Na+ channel-modifying drugs. 0.05% saponin, which completely permeabilizes the vesicles, increases digitoxigenin-sensitive (Na+ + K+)-ATPase, basal Mg2+-ATPase, and (Ca2+ + Mg2+)-ATPase activities by 51.0, 47.4, and 83.6%, respectively. Saponin increases only the Vmax of the latter activity, the Km for Ca2+ (0.13 microM; the same as that for Ca2+-pumping) being unaltered by saponin. An increment of 20.5% in the Vmax of (Ca2+ + Mg2+)-ATPase activity with 10 microM A23187, reveals that the enzyme activity in nonpermeabilized vesicles is limited by the formation of a Ca2+ gradient. Thus, the saponin-induced increment in (Ca2+ + Mg2+)-ATPase due only to exposure of occluded sites (as opposed to Ca2+ gradient dissipation) is actually 52%, which is similar to values for both other ATPases, and suggests that 32-35% of plasma membranes exist in an inverted orientation. Vesicle orientation was independently assessed by the differential actions of tetrodotoxin (a membrane impermeant blocker) and veratridine (a membrane permeant agonist) on Na+-channel opening measured indirectly by dissipation of an imposed Na+ gradient utilized to drive a large 45Ca2+ accumulation via the Na+/Ca2+ exchanger. Tetrodotoxin reverses 35-44% of veratridine-mediated Na+ gradient-dissipation, the relative membrane-permeability of the two channel modifiers, suggesting that 56-65% of sealed vesicles are inverted. The concurrence of these two independent measurements of vesicle orientation reinforces their validity.

Animals↗

Influence of inositol 1,4,5-trisphosphate and guanine nucleotides on intracellular calcium release within the N1E-115 neuronal cell line.

The Ca2+ accumulating properties of a nonmitochondrial intracellular organelle within cultured N1E-115 neuroblastoma cells containing an (ATP + Mg2+)-dependent Ca2+ pump were recently described in detail (Gill, D. L., and Chueh, S. H. (1985) J. Biol. Chem. 260, 9289-9297). Using both saponin-permeabilized N1E-115 cells and microsomal membranes from cells, this report describes the effectiveness of both inositol 1,4,5-trisphosphate (IP3) and guanine nucleotides in mediating Ca2+ release from this internal organelle, believed to be endoplasmic reticulum. Using permeabilized N1E-115 cells, 2 microM IP3 effects rapid release (t1/2 less than 20 s) of approximately 40% of accumulated Ca2+ releasable with 5 microM A23187. Half-maximal Ca2+ release occurs with 0.5 microM IP3, and maximal release with 3 microM IP3. Using a frozen microsomal membrane fraction isolated from lysed cells, 2 microM IP3 rapidly releases (t1/2 less than 30 s) 10-20% of A23187-releasable Ca2+ accumulated within nonmitochondrial Ca2+-pumping vesicles, although only in the presence of 3% polyethylene glycol (PEG). 10 microM GTP, but not guanosine 5'-(beta, gamma-imido)triphosphate (GMPPNP), increases the extent of release in the presence of IP3. Importantly, however, GTP alone induces a substantial release of Ca2+ (up to 40% of releasable Ca2+) with a t1/2 value (60-90 s) slightly longer than that for IP3. The effects of IP3 and GTP are approximately additive, and both effects require 3% PEG. Half-maximal Ca2+ release occurs with 1 microM GTP, with maximal release at 3-5 microM GTP; 20 microM GMPPNP has no effect on release and only slightly inhibits 5 microM GTP; 20 microM GDP promotes full release, but only after a 90-s lag, and initially inhibits the action of 5 microM GTP. Using permeabilized N1E-115 cells, 5 microM GTP with 3% PEG releases greater than 50% of releasable Ca2+; without PEG, GTP still mediates approximately 30% release of Ca2+ from cells. Neither IP3, GTP, or both together (with or without PEG) effects release of Ca2+ accumulated within synaptic plasma membrane vesicles. The profound effectiveness of GTP on Ca2+ release has important implications for intracellular Ca2+ regulation and is probably related to Ca2+ release mediated by IP3.

Adenosine Triphosphate↗

Carbocyclic inosine as a potent anti-leishmanial agent: the metabolism and selective cytotoxic effects of carbocyclic inosine in promastigotes of Leishmania tropica and Leishmania donovani.

Carbocyclic inosine is a potent inhibitor for the growth of the promastigote form of Leishmania tropica and Leishmania donovani. In culture, the EC50 values of carbocyclic inosine are 8.3 X 10(-8) and 1.3 X 10(-7) M for the promastigotes of L. tropica and L. donovani, respectively. On the other hand, it is less toxic towards mouse mammary tumor FM3A cells: the EC50 value is 2.7 X 10(-4) M. Carbocyclic inosine is metabolized by Leishmania promastigotes to give carbocyclic adenosine-5'-triphosphate (aristeromycin-5'-triphosphate) and carbocyclic guanosine-5'-triphosphate. This metabolic conversion provides a mechanism for the parasite-selective toxicity of carbocyclic inosine.

Adenosine↗

Structure- and sequence-specificity of ozone degradation of supercoiled plasmid DNA.

Ozone-reactive sites on the nucleobase moieties in supercoiled pBR322 DNA were investigated by using sequencing procedures. Ozonolysis in the absence of salt resulted in degradation of thymine residues in the A + T rich region located at 3100-3400bp. In the presence of salt, such as NaCl or MgCl2, a conformational change of plasmid DNA was induced. Subsequently the thymine and guanine residues in the loop of the cruciform located at 3120bp and 3220bp were degraded. In addition, central thymine residues present in sequences GTA, GTT and ATA were also degraded.

Base Sequence↗

CD spectra and some properties of deoxyoligonucleotide duplexes having a C:G terminus (nucleosides and nucleotides. Part 69).

In the course of an investigation of the mode of recognition of nucleotide sequences with restriction endonucleases, several deoxyoligonucleotide duplexes having G:C terminal base pairs were synthesized. The oligonucleotides having a 5'-C (3'-G) terminus showed unusual CD spectra with a negative band at the longer wavelength region, when compared to those of the same internal sequences but a 5'-G (3'-C) terminus, which showed a positive band like the B- or A-DNA type. The nature of these CD spectra was compared with those of the Z-DNAs on the effect of salt concentrations, intercalation with ethidium bromide, or 31P-NMR spectra. These unusual spectra may be attributed to the terminal effect of the 5'-C:3'-G pairs.

Base Sequence↗

Serum immunosuppressive acidic protein in renal cell carcinoma.

Serum immunosuppressive acidic protein (IAP) was determined in 45 patients with renal cell carcinoma (20 preoperative and 25 postoperative) and 12 healthy adults. The mean values of serum IAP in patients with renal cell carcinoma of low stage (566.3 +/- 197.7 micrograms/ml) and high stage (936.9 +/- 208.8 micrograms/ml) were statistically higher than those of controls (368.8 +/- 84.5 micrograms/ml). Positive rate of IAP levels was found in 58.3% and 100% of patients with low stage and high stage, respectively. The mean value of serum IAP was 756.4 +/- 361.0 micrograms/ml in patients with metastases, while patients without metastases had a value of 434.7 +/- 170.9 micrograms/ml. There was a statistically significant difference between the two populations. These results suggest that IAP levels appear to provide a useful diagnostic and follow-up marker in renal cell carcinoma patients.

Adult↗

Subcellular distributions of calcium/calmodulin-stimulated and guanine nucleotide-regulated adenylate cyclase activities in the cerebral cortex.

The subcellular distribution of Ca2+/calmodulin-stimulated adenylate cyclase activity was studied in comparison with that of guanine nucleotide-stimulated cyclase activity. The distributions of these activities were similar among the crude fractions but differed among the purified subsynaptosomal fractions. The specific activity of Ca2+/calmodulin-stimulated cyclase was highest in a light synaptic membrane fraction, which has few, if any, postsynaptic densities, whereas that of guanine nucleotide-stimulated cyclase was highest in a heavier synaptic membrane fraction rich in postsynaptic densities. These results suggest that the Ca2+/calmodulin-stimulated cyclase has, at least in part, a different cellular or subcellular location than the guanine nucleotide-stimulated cyclase.

Adenylyl Cyclase Inhibitors↗

Sigmoidocystoplasty after total cystectomy for bladder cancer: a follow-up study.

Data on 47 patients who underwent sigmoidocystoplasty after total cystectomy for bladder cancer from 1960 to 1979 are presented. The overall survival rates were 53.3 per cent at 5 years and 41.3 per cent at 10 years, respectively. The urethral recurrence of cancer occurred in 8 (17 per cent) patients with bladder neck or multiple cancers. Long-term follow-up studies revealed that hydronephrosis with vesico-ureteral reflux and mild acidosis occurred in some patients, but severe deterioration of renal function was nil. We emphasize that sigmoidocystoplasty should widely be considered for patients with extratrigonal bladder cancers infiltrating but not extending beyond the muscle layer.

Adult↗

Spatial and temporal organization of intracellular adenine nucleotides and cyclic nucleotides in relation to rhythmic motility in Physarum plasmodium.

Spatio-temporal organization of a migrating plasmodium was studied both by analysing intracellular concentrations of adenine and cyclic nucleotides and by applying image processing for recording oscillatory changes in thickness with use of microcomputers. ATP and ADP concentrations were about twice as high in the front as in the rear, while AMP distributed uniformly. On the other hand, cAMP and cGMP concentrations were several times higher in the rear than in the front, showing oscillations in between. The cAMP concentrations at the front oscillated with a phase advancing about one-third of the period with respect to the phase of the thickness oscillation, while cGMP concentration there varied only little. ATP concentration oscillated concomitantly with H+. A feedback control loop consisting of (ATP-H+)-cAMP-Ca2+ is proposed. The possible mechanism of rhythmic contractions involving mitochondria which may excrete pulses of Ca2+ and induce cell polarization is discussed.

Adenine Nucleotides↗

High activity of 17 alpha-oxidoreductase in neonatally grafted mouse testes in adult female mice.

Male and female (WB-C57BL/6)F1 hybrid mice were used. Two testes from neonatal mice were grafted into the spleen of adult male and female mice, and the grafted testes were removed 30 and 60 days after grafting. Normal testes from 30- and 60-day old mice were also used. Testicular homogenates were incubated with [14C]4-androstene-3,17-dione or [3H]progesterone, and enzyme activities per g wet tissue and progesterone metabolism were examined. Activity of 17 alpha-oxidoreductase in the grafted testes in females (20 nmol/g/h) was approx. 10 times the activity in the grafted testes in males or in the normal testes, whereas 17 beta-oxidoreductase activity in the grafted testes in females was the lowest among these testes. The bilateral ovariectomy performed 1 month before the grafting of neonatal testes, artificial cryptorchidism performed at 20 days of age, and estrogen treatment for 10 days by diethylstilbestrol pellets resulted in no significant changes in 17 alpha-oxidoreductase activities in 30- and 60-day old grafted, cryptorchid or normal testes. The major 17-hydroxy-C19-steroids formed in vitro from progesterone by the grafted testes in female mice were testosterone and 17 alpha-hydroxy-4-androsten-3-one (epitestosterone), but the formation of epitestosterone was insignificant in the normal testes. The present results demonstrate for the first time that epitestosterone is formed as one of major C19-steroids in neonatally grafted mouse testes in females but not in those in males or in normal mouse testes. However, the mechanisms remain unexplained.

17-Hydroxysteroid Dehydrogenases↗

Hyperprolactinemia enhances LH-stimulated 4-ene-5 alpha-reductase activity but inhibits LH-induced 17-hydroxylase activity in testes of hypophysectomized immature rats.

Two pituitaries from 7-week old female rats (Sprague-Dawley strain) were grafted under the capsule of the left kidney of 21-day old male rat. The pituitary grafted and sham-operated rats were hypophysectomized at 27 days of age. The hypophysectomized rats, in groups of 4, were given daily injections of 9 micrograms NIAMDD-oLH-23 (minimum effective dose) or saline for 3 days starting from day 29. Testicular homogenates were incubated with [3H]progesterone or [14C]4-androstene-3,17-dione, and enzyme activities per testes were estimated. Testicular HCG-binding sites were also measured. Hypophysectomy caused significant decreases in activities of testicular 5 alpha-reductase, 17-hydroxylase, and 17 beta-hydroxysteroid oxidoreductase. These decreased enzyme activities were significantly stimulated by LH treatment. Although pituitary grafts alone showed no effects on these enzyme activities in the testes of the hypophysectomized rats, the grafts significantly enhanced LH-stimulated 5 alpha-reductase activities but inhibited LH-stimulated 17-hydroxylase activity. Testicular LH/HCG receptors were significantly increased by the grafts, especially in the presence of LH, without affecting affinity for HCG. The present results demonstrate for the first time that hyperprolactinemia directly stimulates LH-stimulated 5 alpha-reductase activity in rat testes. The results also show that the same grafts directly inhibit LH-stimulated 17-hydroxylase activity, probably via postreceptor mechanisms.

17-Hydroxysteroid Dehydrogenases↗

Traumatic stenosis of the internal carotid artery in children.

Two cases of stenosis of the internal carotid artery after blunt craniocervical trauma in children are described. Their neurological symptoms developed a few hours after the injury. A superficial temporal artery-middle cerebral artery anastomosis was performed in one, and the other was conservatively treated because of the spontaneous resolution of the stenosis. The pathophysiology and treatment of this clinical entity, especially in children, are discussed.

Accidents, Home↗

Hodgkin's disease in Osaka, Japan (1964-1985).

In the present study, 96 cases of HD selected from 937 cases of malignant lymphomas in Osaka, Japan were reviewed to evaluate a time trend of HD. The results showed that, during the periods from 1964-74 to 1975-85, (1) ratio of HD among all malignant lymphomas decreased from 14.8% to 8.9%, (2) MC decreased and NS increased, and (3) the age of onset fell.

Adolescent↗

A rapid enzyme immunoassay for measurement of HBK in blood.

An enzyme immunoassay has been developed for the measurement of HBK (4-amino-2-hydroxybutylyldibekacin) a new semisynthetic aminoglycoside antibiotic. Antisera were raised in rabbits by immunization with HBK conjugated to bovine serum albumin (BSA). 3'-Eno-HBK conjugated to alkaline phosphatase (ALP) was used as an enzyme labeled antigen. The antibody-bound drug was separated from free using goat anti-rabbit IgG serum. The assay can be completed within one hr by co-incubating the first and the second antibody. The present immunoassay allows detection of 10 ng HBK per ml of serum, and is applicable for monitoring HBK level in blood. HBK concentrations in human sera were determined by the immunoassay during and after infusion and the levels were compared with those determined by high performance liquid chromatography (HPLC) and antimicrobial assay.

Aminoglycosides↗