Biomedical subjects

Y Inoue

Publications and source records attributed to Y Inoue.

At least 1,441 records · Page 80Linked to original sources

PubMed1990

Some electrical properties of human pregnant myometrium.

Membrane properties of the human pregnant myometrium were investigated with the conventional microelectrode and patch clamp methods. The majority of preparations produced spontaneous action potentials at a very low frequency, and action potentials were inhibited in sodium-deficient or calcium-free solutions. With the patch clamp technique with 120 mmol/L cesium-20 mmol/L tetraethylammonium in the pipette, the inward current was evoked by a depolarizing pulse above -40 mV from a holding potential of -60 mV and maximum amplitude was obtained at 0 mV. At a holding potential of -100 mV, the inward current could be evoked with less positive depolarizing pulses, and the membrane potential that evoked the maximum amplitude of inward current was shifted to a more negative potential. Single-channel current recording revealed that two types of calcium channels existed in human pregnant myometrium, with single-channel conductances of 12 and 29 pS. One of the calcium channels (12 pS) was inactivated at a holding potential of -60 mV.

Action Potentials↗

PubMed1990

Differential response of B cells in the lymph node and the spleen to bacterial lipopolysaccharide.

In vivo polyclonal activation of B cells in the lymph nodes and the spleens of mice injected with bacterial lipopolysaccharide (LPS) was compared. The peak of anti-trinitrophenylated sheep red blood cells plaque-forming cell (PFC) response in the lymph node was reached 6-8 days after the injection of LPS while that in the spleen was reached at 2 days. The maximal increase in the total number of Ig-producing cells in the lymph node also occurred at the later stage. These differences in time courses of polyclonal activation of B cells between the lymph node and the spleen were not due to the absence of B cells in the lymph node, migration of PFC from the spleen to the lymph node, or qualitative differences of B cells. This phenomenon was dependent on the environmental difference between the lymph node and the spleen, because B cells from the lymph node could respond to LPS rapidly in the spleen. Further, the polyclonal activation of B cells was accelerated in the lymph nodes of mice receiving prior injection of LPS. In in vitro cultures of lymph node cells of those mice, a significant amount of interleukin-1 could be detected by stimulation of LPS. It was possible that the delayed activation of B cells in the lymph node was due to the time lag necessary for construction of the environmental condition suitable for activation of B cells, whereas in the spleen this condition can be provided without delay.

Animals↗

PubMed1990

Architecture of Purkinje cells of the reeler mutant mouse observed by immunohistochemistry for the inositol 1,4,5-trisphosphate receptor protein P400.

P400 protein, which is identical to the inositol 1,4,5-trisphosphate receptor protein, is a glycoprotein closely associated with the membranes of Purkinje cells. Three types of monoclonal antibodies against P400 protein were employed for the immunohistochemical detection of Purkinje cells in the cerebellum and brainstem of the normal and reeler mouse. Purkinje cells in both types of mice were immunoreactive against anti-P400 antibodies, and the soma, dendrites, axon and even terminal boutons in the cerebellar and vestibular nuclei could be clearly visualized. In the cerebellum of the reeler mutant, the heterotopic Purkinje cells both within and below the granule cell layer were also immunopositive and could be clearly differentiated from the deep cerebellar nuclei, in which neurons were immunonegative. The molecular layer of the reeler cerebellum varied in thickness and certain parts were completely defective. The dendrites within the molecular layer extended from Purkinje cells whose cell bodies were located in the normal position, abnormally in the granule cell layer, or at the surface of the central mass. Outside the cortex of the cerebellum, ectopic Purkinje cells were demonstrated in 3 cerebellar nuclei, the cerebellar medulla and peduncle, and brainstem of the normal and reeler mouse.

Animals↗

PubMed1990

Effect of SQ29,852, a new angiotensin converting enzyme (ACE) inhibitor with a phosphonic acid group, on the activity of angiotensin converting enzyme from human kidney.

1. An in vitro experiment was carried out to compare the inhibitory effect of SQ29,852 on human renal angiotensin converting enzyme (ACE) with those of captopril, enalapril and enalaprilat. 2. SQ29,852 strongly inhibited human renal ACE; its IC50 value was 1.5 x 10(-8) M. In terms of the IC50, SQ29,852's efficacy was about 1/10 of that of captopril and 1/28 of that of enalaprilat, but it was about 14 times more potent than enalapril. 3. SQ29,852 showed no inhibitory effects on cathepsin D, urinary kallikrein, renal renin, pepsin, trypsin and chymotrypsin. Its ACE-specificity was higher than that of captopril. 4. ACE inhibition by SQ29,852 was shown to be competitive, as revealed by Lineweaver-Burk plots. The affinity of SQ29,852 to ACE was shown to be high by a Ki value of 1.2 x 10(-8) M.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1990

REM sleep abnormalities in severe athetoid cerebral palsy.

Various abnormalities of sleep have been reported in extrapyramidal diseases in adults. We have investigated the disturbances of REM sleep (SREM) in severe athetoid cerebral palsy (ACP) originating perinatally. Ten ACP patients, 5 males and 5 females ranging from 15 to 30 years old, were studied by means of all-night polygraphic examination. Three cases showed a marked decrease in rapid eye movements in SREM. Moreover, the tone of submental muscle in SREM was also disturbed in three. Regarding body movements during sleep, gross movements and twitch movements of the submental muscle were analyzed. In most of the patients, an abnormal distribution of body movements according to sleep stages was observed, the rate being significantly reduced in SREM. REMs, atonia and body movements are considered to be related to the brainstem function in animals. The results of the present study suggest that perinatal extrapyramidal diseases could also coincide with brainstem dysfunctions.

Adolescent↗

PubMed1990

Synthesis and antibacterial activity of thiazolo-, oxazolo-, and imidazolo[3,2-a][1,8]naphthyridinecarboxylic acids.

It is known that thiazolo[3,2-a][1,8]naphthyridine derivatives (3a) exhibit good antibacterial activity. Accordingly, several analogues of 3a, viz. oxazolo- and imidazolo[3,2-a][1,8]naphthyridine derivatives 3b and 3c, were synthesized and evaluated for antibacterial activity in vitro and for inhibitory activity against DNA gyrase of Escherichia coli K-12 C600. Compound 3a exhibited antibacterial activity comparable to that of ofloxacin and enoxacin against Gram-positive and Gram-negative bacteria and displayed antibacterial activity superior to that of 3b and 3c. The antibacterial activities of 3b and 3c decreased in that order. DNA gyrase inhibitory activities of 3a-c in E. coli K-12 C600 paralleled their in vitro antibacterial activity. It was found that enhancement of the DNA gyrase inhibitory activity of 3a was dependent on a certain feature of the sulfur atom of the thiazole ring.

Anti-Bacterial Agents↗

PubMed1990

Synthesis of antimicrobial agents. 3. Syntheses and antibacterial activities of 7-(4-hydroxypiperazin-1-yl)quinolones.

A series of novel pyridone carboxylic acids having a 4-hydroxypiperazinyl group at the 7-position of norfloxacin and ciprofloxacin were prepared. The in vivo antibacterial efficacies of these compounds were superior to those of corresponding piperazinyl derivatives. From the results of the studies on the pharmacokinetic profile and toxicity, the 4-hydroxypiperazinyl derivatives were confirmed to be pharmacologically superior to corresponding piperazinyl derivatives. Thus, a 4-hydroxypiperazinyl group was revealed to be a beneficial substituent for potential use in future quinolone antibacterials.

Administration, Oral↗

PubMed1990

Molecular cloning and characterization of cDNAs coding for apopolysialoglycoproteins in cherry salmon (Oncorhynchus masou) eggs.

Recently we have cloned the cDNAs and genomic DNAs for apopolysialoglycoproteins (apoPSGPs) of Salmo gairdneri (rainbow trout) [Sorimachi, H., Emori, Y., Kawasaki, H., Kitajima, K., Inoue, S., Suzuki, K., & Inoue, Y. (1988) J. Biol. Chem. 262, 17678-17684], and the sequence analyses have indicated that the mRNAs for apoPSGPs vary in length and contain different numbers of identical 39-bp repeating units encoding the tridecapeptide (Asp-Asp-Ala-Thr-Ser-Glu-Ala-Ala-Thr-Gly-Pro-Ser-Gly) as well as highly conserved sequences encoding pre-, pro-, and telo-peptide regions. In this study we isolated cDNA clones for yamame (cherry salmon, river resident form; Oncorhynchus masou ishikawai) apoPSGP using a genomic DNA fragment for rainbow trout apoPSGP as a probe. The nucleotide sequence analyses revealed that the structures of mRNAs for yamame apoPSGP including the noncoding regions are essentially identical to those for rainbow trout, showing 90% sequence identity. Within the repeating region, 4 bp out of the 39 were replaced, producing a different tridecapeptide, Asp-Asp-Ala-Thr-Ser-Glu-Ala-Ala-Thr-Gly-Pro-Ser-Ser. This tridecapeptide is unique to yamame and common among all cDNAs obtained from yamame. Genomic Southern blot analysis showed that the yamame apoPSGP genes constituted a multiple gene family with a similar gene organization to that of rainbow trout. Oligodeoxynucleotide probes (18 bases) synthesized based on specific sequences for the yamame repeating unit hybridized only to the yamame DNA and not to the rainbow trout DNA, and vice versa.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1990

Sexual response of Saccharomyces cerevisiae: phosphorylation of yeast glyoxalase I by a cell extract of mating factor-treated cells.

The phosphorylation of glyoxalase I was observed when the phosphatase-treated enzyme was incubated in the presence of [gamma-32P]ATP and a cell extract prepared from alpha-type yeast cells which had been treated with the culture supernatant of a-type yeast cells. The phosphorylated protein was identified as glyoxalase I by using anti-glyoxalase I rabbit immunoglobulin G.

Basidiomycota↗

PubMed1990

Mn K-edge XANES spectroscopy of a photosynthetic O2-evolving complex. High-quality pre-edge features and distinct fine structures in the S1- and S2-states.

High-resolution XANES (X-ray Absorption Near Edge Structure) spectroscopy for Mn in the S1 and S2 states of the spinach photosynthetic O2-evolving complex revealed distinct features in K-edge spectra, when a high signal-to-noise (S/N) ratio of ca. 80 with a low and constant background-to-signal (B/S) ratio of 0.15 to 0.18 was attained. Six features resolved in each S-state spectrum involve a pre-edge feature due to 1s----3d transitions, a main-edge feature possibly due to 1s----4s transitions and four fine structures superimposed on the principal absorption bands due to 1s----4p* transitions. The high-quality pre-edge features were analyzed according to a parametric ligand-field theory in comparison with those of some typical authentic Mn complexes. It was deduced that i) all of the four Mn ions in the S1-state are octahedrally coordinated and two of them constitute a di-mu-oxo bridged Mn(III, III) dimeric subunit; ii) the bridged Mn(III) ions are further bridged by a deprotonated water dimer, (HOHOH)-, and coordinated by imidazole-N and carboxylate-O- on the opposite side of the Mn atom from the di-mu-oxo bridge; iii) the other two Mn ions exist in the form of Mn(III) monomeric subunits; and iv) upon the S1----S2 transition, only the bridged Mn(III,III) is oxidized to Mn(III,IV). The distinct change in the principal absorption band shape upon the S1----S2 transition is briefly discussed to obtain the XANES evidence for a tetrameric Mn-cluster.

Cell Membrane↗

PubMed1990

Induction of killer cells from lymphocytes in pleural effusion of advanced lung cancer patients.

We analyzed the phenotype and cytotoxic ability of pleural exudative lymphocytes (PLEL) which were obtained from 18 advanced lung cancer patients. Freshly isolated PLEL were mainly CD4(+) T cells and had weak natural killer, autologous tumor killing and lymphokine-activated killer activities. After cultivation of PLEL with interleukin-2, cytotoxicity of PLEL against autologous tumor cells was increased at 2 weeks, but it was remarkably reduced at 4 weeks. When PLEL were stimulated by mitomycin C-treated autologous tumor cells during culture, autologous tumor killing activity of PLEL was significantly enhanced even after 4 weeks of cultivation. Cold target inhibition analysis and binding inhibition assays using monoclonal antibodies indicated that autologous tumor stimulation could induce major histocompatibility complex class I restricted cytotoxic T lymphocytes specific for autologous tumor cells in some cases.

Adenocarcinoma↗

PubMed1990

Ventricular enlargement in normal weight bulimia.

Cranial computed tomography (CT) scans of 17 patients with bulimia were compared with those of 21 age- and sex-matched controls. The ventricular brain ratio (VBR) of the bulimics was 7.29, which was significantly greater than the 4.55 seen in controls. However, no correlation was found between VBRs and clinical variables, endocrine or metabolic parameters.

Adolescent↗

PubMed1990

Endothelin augments unitary calcium channel currents on the smooth muscle cell membrane of guinea-pig portal vein.

1. The effects of endothelin (ET) on the Ca2+ channel current in smooth muscle cells of the guinea-pig portal vein were investigated using the patch-clamp technique with whole-cell and cell-attached configurations. 2. ET augmented the macroscopic Ba2+ current in a dose-dependent manner; this effect was inhibited by nifedipine or Cd2+. Augmentation of the inward current by ET did not depend on the amplitude of the depolarizing pulse. Further, when the membrane potential was held at -60 mV, ET increased the amplitude of the Ba2+ inward current measured at the peak and end of the depolarizing pulse to the same extent. 3. By contrast, when the membrane potential was held at -80 mV, depolarizing pulses to potentials more negative than 0 mV produced greater augmentation of the inward current than did those more positive than 0 mV. Moreover, when a depolarizing pulse to below 0 mV was applied, ET increased the peak amplitude of the inward current more than the amplitude measured at the end of pulse. 4. Using the patch-clamp technique with cell-attached configuration, two types of unitary Ba2+ current with conductances of 22 and 12 pS were obtained in 50 mM-Ba2+ solution. Nifedipine inhibited both types of unitary channel current, but the sensitivity of the 22 pS Ca2+ channel to nifedipine was 20-fold higher than the 12 pS Ca2+ channel. 5. Bath application of ET prolonged the mean open time, reduced the number of sweeps in which no Ca2+ channel was opened ('blank' sweep), and increased the number of channel openings evoked by each depolarizing pulse without changes of conductance. As a consequence, ET increased the open probability of both channels. 6. Augmentation of the 12 pS channels by ET was seen only in the early phase of a depolarizing pulse (57 ms from the onset of 170 ms pulse), while augmentation of the 22 pS channels was seen during the entire period of a depolarizing pulse. 7. When ET was added to the pipette solution, the activity of both Ca2+ channels was increased. However, this effect was less frequently observed than when ET was applied in the bath. 8. These results suggest that ET augments both the nifedipine-sensitive and resistant Ca2+ channels in the smooth muscle cell membrane of the guinea-pig portal vein, but in different ways. Presumably, ET acts indirectly on the voltage-dependent Ca2+ channel.

Animals↗

PubMed1990

Purification and characterization of a novel nucleoside phosphorylase from a Klebsiella sp. and its use in the enzymatic production of adenine arabinoside.

An adenosine-assimilating bacterium, Klebsiella sp. strain LF1202, inducibly formed a novel nucleoside phosphorylase which acted on both purine and pyrimidine nucleosides when the cells were cultured in medium containing adenosine as a sole source of carbon and nitrogen. The enzyme was purified (approximately 83-fold, with a 17% activity yield) to the homogeneous state by polyacrylamide gel electrophoresis. The molecular weight of the purified enzyme was calculated to be 125,000 by gel filtration of Sephadex G-200 column chromatography, although the enzyme migrated as a single protein band with a molecular weight of 25,000 on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis; thus, it was thought to consist of five identical subunits. Besides purine nucleosides (adenosine, inosine, and guanosine), the purified enzyme also acted on pyrimidine nucleosides such as uridine, 2'-deoxyuridine, and thymidine. The purified enzyme catalyzed the synthesis of adenine arabinoside, a selective antiviral pharmaceutic agent, from uridine arabinoside and adenine.

Adenine↗

PubMed1990

Bacterial Accumulation of Metallic Compounds.

Xanthomonas maltophilia accumulated metals or metallic compounds within the cell in the form of one or a few particles, in a peculiar condition similar to that of an electrolyte solution in an electric cell. The particles consisted of many little granules, most of which were assumed to be composed mainly of a compound of zinc and phosphorus in an amorphous state.

Journal Article↗

PubMed1990

Rapid and reversible inhibition by low density lipoprotein of the endothelium-dependent relaxation to hemostatic substances in porcine coronary arteries. Heat and acid labile factors in low density lipoprotein mediate the inhibition.

The effects of hemostatic substances on the vascular tone in porcine coronary arteries and the influence of low density lipoprotein on tension were investigated. Thrombin induced a marked concentration-dependent relaxation in prostaglandin F2 alpha-precontracted strips with intact endothelium, whereas it produced a modest constriction in endothelium-denuded arteries. Methylene blue abolished the relaxation, but indomethacin did not affect it significantly. An exposure of the intact strips to low density lipoprotein resulted in a marked inhibition of the relaxation to thrombin but did not interfere with vasodilation by sodium nitroprusside. The inhibition by low density lipoprotein was reversed completely by washing. In contrast, high density lipoprotein lacked such inhibitory effects. Adenosine diphosphate, calcium ionophore A23187, and platelet-activating factor also produced relaxation in the intact strips. An exposure of the strips to low density lipoprotein almost abolished relaxation to these substances. The inhibition was also reversible. Heat treatment or acid treatment of low density lipoprotein resulted in a complete loss of the inhibitory effects, but diisopropyl fluorophosphate treatment did not alter the effect. It is concluded that low density lipoprotein may play a new pathological role in promotion of coronary vasospasm through rapid and reversible inhibition in endothelium-dependent relaxation to hemostatic substances.

Acids↗

PubMed1990

Dual action of FRC8653, a novel dihydropyridine derivative, on the Ba2+ current recorded from the rabbit basilar artery.

Actions of FRC8653 on the macroscopic and unitary Ba2+ currents were studied using the rabbit basilar artery. Application of (+/-)-FRC8653 (less than 1 microM) increased the amplitude of the inward current when depolarization pulses more negative than -10 mV were applied but inhibited it when depolarization was more positive than 0 mV (in each case from a holding potential of -80 mV). At a holding potential of -40 mV, (+/-)-FRC8653 (greater than 0.1 nM) consistently inhibited the inward current. (-)-FRC8653 (greater than 1 nM) inhibited the amplitude of the inward current evoked by a depolarizing pulse more positive than -10 mV (the holding potential being -80 mV). At the holding potential of -80 mV, but not at -40 mV, (+)-FRC8653 (1 microM) enhanced the current amplitude evoked by a depolarizing pulse more negative than -10 mV but inhibited the current evoked by a pulse more positive than 0 mV. (+/-)-FRC8653 shifted the voltage-dependent inhibition curves to the left, and the slope of the curve became steeper (test pulse of +10 mV). Two types of single Ca2+ channel currents (12 and 23 pS) were recorded from the basilar artery by the cell-attached patch-clamp method. Opening of the 12-pS channel occurred with a depolarizing pulse (-20 mV) from a holding potential of -80 mV, but not from one of -60 mV. (+)-FRC8653 activated, and (-)-FRC8653 inhibited, the 23-pS channel.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1990

Studies on sustained-release suppositories. III. Rectal absorption of morphine in rabbits and prolongation of its absorption by alginic acid addition.

Rectal absorption of morphine from various kinds of suppository bases was investigated. The extent of bioavailability of morphine by rectal administration varied with the bases used (30.5-97.5%), but every value was higher than that in the case of oral administration (13.5%). Witepsol bases were preferable to macrogol base for the rectal absorption of morphine. In particular, Witepsol S-55 or W-35 gave a higher plasma peak level than H-15 or E-75, whereas the difference in the mean residence times obtained from these bases could not be regarded as significant. Sustained-release suppositories of morphine could be prepared simply by mixing alginic acid (Alg) with morphine in a suppository base. Further, prolonged rectal absorption could be obtained by using these sustained-release suppositories, and the absorption rate was controlled by the amount of Alg added. It seems likely that the sustained release was due to the binding of morphine to Alg from the results of partition coefficient and binding ratio measurements in aqueous solution. The rapid initial absorption and the subsequent prolonged absorption of morphine simultaneously obtained from the morphine-Alg suppository may be useful in the clinical context.

Alginates↗