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Biomedical subjects

K Satoh

Publications and source records attributed to K Satoh.

At least 1,027 records · Page 57Linked to original sources
PubMed1986

Rapid induction of nucleoside-diphosphate kinase in HeLa S3 cells by human-type interferons.

Nucleoside-diphosphate (NDP)-kinase can be considered to be induced by human-type interferons (HuIFNs) rapidly, since an enzyme increase was detected within 2 h of incubation of HeLa S3 cells with HuIFNs, while incubation with heterologous mouse IFNs had no such effect. The enzyme increase induced by HuIFNs reached a plateau at 6 h after treatment. Actinomycin D (0.5 microgram/ml) significantly blocked the enzyme increase induced by HuIFNs in the cells. A possible biological role of the enzyme in the IFN-induced biochemical events is discussed.

Adenosine Diphosphate↗
PubMed1986

DDAVP in acquired von Willebrand syndrome associated with multiple myeloma.

The response to a single intravenous infusion of 1-deamino-8-D-arginine vasopressin (DDAVP, desmopressin) was studied in two patients with acquired von Willebrand syndrome associated with IgG-kappa myeloma. Following infusion of DDAVP (0.3-0.4 micrograms/kg), prolonged bleeding time was normalized; plasma ristocetin cofactor activity, von Willebrand factor antigen, and factor VIII activity were remarkably increased; and high-molecular-weight forms of von Willebrand factor were demonstrated by crossed immunoelectrophoresis in both patients. Excellent hemostasis was achieved following administration of DDAVP in one patient when it was used for the treatment of gum bleeding and for the prophylaxis of bleeding during and after dental extractions. These observations suggest that DDAVP is an effective alternative to blood products for at least some patients with acquired von Willebrand syndrome in addition to patients with inherited von Willebrand disease, hemophilia A, and uremia.

Blood Coagulation Tests↗
PubMed1986

Cholinergic innervation of the rat's labyrinth.

Efferent vestibular and cochlear neurons were identified in the rat's brain stem by retrograde labelling with True Blue (TB) or wheat germ agglutinin - horseradish peroxidase (WGA-HRP) injected into the utricle. Such cells were found at the same locations described in 1983 by White and Warr (ipsilateral superior olivary nucleus (LSO), bilateral latero-ventral nucleus of the trapezoid body (LTz) bilateral group E medial and lateral to the genu facialis) and, in addition, bilaterally in the caudal pontine reticular nucleus (CPR) at the level of the descending facial nerve. Cholinergic neurons were identified by counterstaining sections containing TB filled perikarya for acetylcholinesterase (AChE) following pretreatment with diisopropylfluorophosphate (DFP) or choline acetyltransferase (ChAT), by immunohistochemistry with highly specific monoclonal antibodies. Many, but not all, vestibular efferent cell bodies located in group E were shown to be cholinergic. These and other recently published data suggest that the efferent octavus system may consist of a number of chemically distinct cell groups.

Acetylcholinesterase↗
PubMed1986

Torsion of the gallbladder.

A 77-year-old Japanese woman with torsion of the gallbladder was surgically treated. Perhaps because of its rarity, the diagnosis is seldom made clinically, the condition generally being recognized only at laparotomy. Discussed herein are the possibility of preoperative diagnosis of this condition and the usefulness of ultrasonotomography.

Aged↗
PubMed1986

Metabolism of arachidonic acid and synthesis of prostanoids in human endometrium and decidua.

Arachidonic acid metabolism and prostanoid synthesis were investigated using [14C]-arachidonic acid (AA) in human endometrium obtained at different phases of the ovarian cycle and decidua in early pregnancy. Prostaglandins (PG) identified in endometrium and decidua were PGE2 and PGF2 alpha. The capacity for the production of PGE2 and PGF2 alpha was higher in the secretory phase of endometrium than in the proliferative phase, and the maximum formation of PGE2 and PGF2 alpha was found in the mid secretory phase and in the late secretory phase, respectively. However, the production of PGs was markedly suppressed in decidua. On the other hand, more than 70% of [14C]AA was incorporated into total neutral lipids, whereas less than 22% was incorporated into glycerophospholipids in both endometrium and decidua. Secretory endometrium showed a higher uptake of [14C]AA into glycerophospholipids than did proliferative endometrium, whereas the incorporation into neutral lipids was lower in secretory endometrium than in the proliferative phase. Moreover, decidua showed a similar pattern of incorporation of [14C]AA to the proliferative phase. The changes of arachidonic acid metabolism and PG formation in both endometrium and decidua are discussed in terms of implantation and maintenance of early pregnancy.

Arachidonic Acid↗
PubMed1986

The localization of central cholinergic neurons.

Over the past decade our understanding of the localization of central cholinergic neurons has greatly increased. Interest in these systems has also intensified due to the involvement of cholinergic mechanisms in Alzheimer's disease. The distribution of central cholinergic neurons is reviewed, focusing on recent work in experimental animals. The pharmacohistochemical procedure for acetylcholinesterase and the development of antibodies to choline acetyltransferase are two of the major technical advances that have shaped our knowledge of the distribution of central cholinergic neurons. The results, advantages and limitations of both techniques are discussed. A discussion of the phenomenon of coexistence of acetylcholine with neuroactive peptides in central neurons is also included.

Acetylcholinesterase↗
PubMed1986

Modification potentials of ethyl alcohol and acetaldehyde on development of preneoplastic glutathione S-transferase P-form-positive liver cell foci initiated by diethylnitrosamine in the rat.

The modification potentials of ethyl alcohol (EA) and acetaldehyde (AA) on development of immunohistochemical glutathione S-transferase (placental type)-positive (GST-P+) liver cell foci were examined in an in vivo short-term assay system. Rats were given a single intraperitoneal injection of diethylnitrosamine (DEN) and then various concentrations of EA (20, 10, 5%) or AA (5, 2.5%) in their drinking water from week 2 till termination in week 6. All rats were subjected to two-thirds partial hepatectomy in week 3. Animals given EA (20% and 10%) or AA showed significant decrease in liver and body weight. However, only EA caused significant dose-related inhibition of development of areas of foci (mm2/cm2), but AA had no effect on their development.

Acetaldehyde↗
PubMed1986

Neuropeptides and NADPH-diaphorase activity in the ascending cholinergic reticular system of the rat.

A major group of cholinergic neurons is present in the midbrain and pontine tegmentum. These cells could be selectively stained using either monoclonal antibodies to choline acetyltransferase, the pharmacohistochemical acetylcholinesterase procedure, or reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry. Using these three techniques, the precise distribution of this cell group was determined. By combining these techniques with immunohistochemical staining for various neuropeptides, examples of peptide-cholinergic coexistence could be demonstrated in this cell group. Approximately 30% of these cholinergic neurons displayed substance P immunoreactivity. Most of these cells also showed corticotropin-releasing factor immunoreactivity and bombesin/gastrin-releasing peptide immunoreactivity. These results therefore provide evidence for the coexistence of various neuropeptides together with NADPH-diaphorase activity in the ascending cholinergic reticular system.

Acetylcholinesterase↗
PubMed1986

The effects of osmotic tissue dehydration and air drying on morphology and energy transfer in two species of porphyra.

Studies were conducted to document the effects on morphology and energy transfer in photosynthesis of severe tissue dehydration induced either by air-drying or by immersing the tissues of two Porphyra species in hyperosmotic solutions. These studies showed that the dehydration-tolerant intertidal alga, Porphyra perforata J.Ag., was almost unaffected by either of these treatments, while the dehydration-sensitive Porphyra nereocystis Anders. was damaged similary by both treatments. Damage to that sensitive species was characterized by ruptured organelles as seen by interference microscopy as well as by increased fluorescence emission at 682 nanometers emanating from allophycocyanin. These results suggest that a disruption of energy transfer between allophycocyanin and chlorophyll a occurs because of the damage to membranes following tissue dehydration, and that the increase in the yield of phycobilin fluorescence is a good indicator of these phenomena. Thus, air-drying and osmotic-dehydration appear to have similar physiological consequences in a dehydration-sensitive alga but almost no effect in a tolerant species.

Journal Article↗
PubMed1986

No effect of atrial natriuretic factor on cardiac rate, force and transmitter release.

The effects of atrial natriuretic factor (ANF, 1-300 nmol/l) on cardiac rate, force and neurotransmitter release were examined in guinea-pig isolated heart preparations. Synthetic ANF had little effect on the contractile force of electrically driven papillary muscle regardless of the presence or absence of isoprenaline. The pulse period of spontaneously beating right atria was not affected by ANF. Neither the positive nor negative chronotropic effect of isoprenaline or bethanechol respectively were changed in the presence of ANF. ANF did not affect the release of neurotransmitter from the nerve endings in the isolated atrium. ANF was confirmed to relax isolated aortic rings precontracted with either noradrenaline (ANF,IC50 = 3 nmol/l,s.e.m. = 0.2, n = 5) or potassium (ANF,IC50 = 24 nmol/l, s.e.m. = 0.2, n = 5). These results demonstrate that ANF within doses effective for vasorelaxation has no appreciable effect on myocardial function or neutrotransmitter release in the heart.

Adrenergic Fibers↗
PubMed1986

Endothelium-dependent relaxation is unaltered by hypertension, cholesterol or intimal thickening.

The effect of cellophane wrap hypertension (WRAP) and hypercholesterolemia (1% cholesterol diet, CHOL) for 4 weeks was assessed on the endothelium-dependent vasodilator response to acetylcholine in conscious rabbits after pharmacological autonomic blockade. Dose-response curves for the hindlimb vascular resistance (ear artery pressure/lower aortic blood flow; Doppler flowmeter) and acetylcholine infusion (i.v.) doses were unaltered in sensitivity (ED50) for any of the treatment groups. The range and slope of the curves were significantly altered by WRAP, CHOL or WRAP plus CHOL for acetylcholine and adenosine infusions consistent with medial hypertrophy in resistance vessels and raised serum viscosity. The effect of intimal thickening on the response to endothelium derived relaxing factor (EDRF) was tested in dog carotid artery ring segments in vitro 4 weeks after endothelium removal. The relaxation responses to acetylcholine (EDRF-dependent) and adenosine or nitroglycerin were not significantly altered by the neo-intima. Therefore the response to EDRF released by acetylcholine in resistance vessels was unaltered by hypertension, hypercholesterolemia or both together. Neo-intimal thickening in response to initial endothelium loss does not appear to alter EDRF responses in the carotid artery.

Animals↗
PubMed1986

Alpha 2-adrenoceptors and endothelium-dependent relaxation in canine large arteries.

Ring preparations from the carotid, coronary, renal, mesenteric and femoral arteries of the dog were precontracted with the thromboxane mimetic U46619, after ensuring that the resting conditions were comparable from the Laplace relationship. In the presence of prazosin (1 microM) and propranolol (3 microM), noradrenaline (NA) relaxed the arteries in the order coronary greater than carotid greater than femoral greater than renal = mesenteric. When maximum relaxation to nitroglycerin (10 microM) was taken to be 100% the maximum relaxation to noradrenaline in each artery was: coronary 70%; carotid 34%; femoral 19%; renal 7% and mesenteric 2%. In endothelium-intact arteries UK14304 mimicked the relaxation responses to NA and idazoxan shifted the curves to both agonists to the right, consistent with an alpha 2-adrenoceptor classification. Substance P relaxed the arteries in the same order as for NA but showed higher efficacy i.e.: coronary 100%; carotid 80%; femoral 71% renal 49%; and mesenteric 41%. Removal of the endothelium abolished the relaxation to NA. We conclude that endothelium-dependent relaxation to NA and substance P varies greatly across 5 large arteries of the dog. This may indicate that endothelium-derived relaxing factor (EDRF) release is site-dependent or that the efficacy of EDRF on smooth muscle varies; being greatest in the coronary and weakest in the renal and mesenteric arteries.

Animals↗
PubMed1986

Single-serum diagnosis of rubella by combined use of the hemagglutination inhibition and passive hemagglutination tests.

We explored the feasibility of using the passive hemagglutination (PHA) test in combination with the hemagglutination inhibition (HI) test for the single-serum diagnosis of rubella. We found by sedimentation analysis of the serum that early 7S antibody produced within 1 month after the onset of the rash had high HI but much lower PHA titers, whereas the PHA titers of antibody produced later were slightly higher than the HI titers. (19S antibody in the early serum had some PHA activity.) This disparity between the HI and PHA activities of the early 7S antibody could be used for the routine diagnosis of rubella. A comparison of the HI titers of the test serum with the PHA titers of mercaptoethanol-treated serum constitutes a simple method for determining whether the serum sample was taken shortly or remotely after the infection.

Antibodies, Viral↗
PubMed1986

Cardiohemodynamic effects of nipradilol (K-351) in the dog: comparison with propranolol, nadolol and prazosin.

The cardiohemodynamic effects of nipradilol (K-351) were studied in comparison with those of propranolol, nadolol and prazosin in anesthetized, open-chest dogs. All drugs were administered intravenously. Nipradilol produced dose-dependent decreases in systemic blood pressure (BP), heart rate (HR), venous return (VR) and cardiac output (COP), but virtually no change in right atrial pressure (RAP). Propranolol decreased HR, tended to decrease VR and COP and increased RAP, but produced no change in systemic BP. Nadolol also decreased HR, VR and COP and increased RAP, but did not change systemic BP. Prazosin decreased systemic BP, VR and COP and tended to decrease RAP, but scarcely affected HR. After propranolol or nadolol, nipradilol failed to reduce HR, but still produced definite decreases in systemic BP, VR and COP and a slight decrease in RAP. After prazosin, nipradilol still produced decreases in systemic BP, HR, VR and COP. These results suggest that nipradilol decreases VR and COP mainly by increasing venous capacitance through direct venodilator action and in part by increasing resistance to VR through beta-adrenoceptor blockade. This effect also appears to be responsible for its hypotensive effect.

Adrenergic beta-Antagonists↗
PubMed1986

Spontaneous autoimmune thyroiditis in Bio Breeding/Worcester (BB/W) rat.

We investigated the serial changes in the plasma levels of anti-thyroglobulin antibody (ATA) by solid-phase enzyme immunoassay, thyroid hormones and blood glucose, since spontaneous occurring lymphocytic thyroiditis (LT) has been found in spontaneously diabetic Bio Breeding/Worcester (BB/W) rat. We also observed the correlation between these levels and histological findings in the thyroid gland. The incidence of diabetes was 0% in 5 week old rats (group A), 70% in 11 week old rats (group B), and 86% in 20 week old rats (group C), while LT was observed in 0% in group A, 20% in group B and 48% in group C. Although the incidence of both increased with age, there was no link between LT and diabetes. Plasma ATA levels were 91.4 +/- 28.5 (OD492 X 1,000, mean +/- SEM) in the control (14 week old Wistar Furth) rats. 49.5 +/- 15.4 in group A, 197.8 +/- 41.5 in group B, and 376.7 +/- 48.7 in group C, again showing a clear increase with age. In group C, the plasma levels of ATA in rats with LT were significantly higher than those without LT. In addition, 6 out of 11 rats without LT had abnormaly high ATA levels. In group C, the plasma levels of free 3,5,3'-triiodothyronine (FT3) and total thyroxine (TT4), and also the FT3/TT4 ratio were significantly lower and the plasma levels of blood glucose were higher than in the other groups. There was no difference between the plasma thyroid hormone levels in rats with LT and those without LT. These studies suggest that LT may occur independently of insulitis, namely diabetes, ATA levels and the incidence of LT increase with age, the site of ATA production may not be confined to the thyroid gland, and the derangement of glucose metabolism may be one of the factors in the decrease in plasma thyroid hormone. The BB/W rat is not only a useful animal model to use in exploring the pathogenesis of human insulin-dependent diabetes mellitus, but also spontaneous autoimmune thyroiditis.

Age Factors↗
PubMed1986

Comparative study of coronary vasodilator and cardiac effects of nitrendipine by use of isolated, blood-perfused dog heart preparations.

The coronary vasodilator and cardiac effects of 3-ethyl-5-methyl-1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl) -3,5-pyridinedicarboxylate (nitrendipine, Bay e 5009) were compared in isolated, blood-perfused sinoatrial (SA) node, atrioventricular (AV) node and papillary muscle preparations of dogs with i.a. administration. In all preparations nitrendipine increased (coronary) blood flow. In SA node preparations nitrendipine reduced sinus rate but the reduction remained only about 13% of the basal value even at the highest dose. The dose estimated to produce a 15% (nearly a half maximum) decrease in sinus rate was about 8 times the dose which doubled coronary blood flow. In AV node preparations nitrendipine prolonged AV conduction time when injected into the artery supplying the AV node but the prolongation remained only about 12% of the basal value even at the highest dose. The dose estimated to produce a 15% (nearly a half maximum) increase in AV conduction time was about 11 times the dose which doubled coronary blood flow. When injected into the artery supplying the His-Purkinje ventricular system of AV node preparations, nitrendipine was entirely ineffective on AV conduction. In paced papillary muscle preparations nitrendipine reduced force of contraction. The reduction, however, remained less than 50% of the basal value even at the highest dose. The dose estimated to reduce force of contraction by half was about 11 times the dose which doubled coronary blood flow. Nitrendipine was entirely ineffective on ventricular beating rate of spontaneously beating papillary muscle preparations. These results indicate that nitrendipine is highly vasoselective, and warrant its high efficacy as an antianginal drug.

Animals↗
PubMed1986

The alpha adrenoceptors on endothelial cells.

Endothelial cells release a powerful factor (endothelium-derived relaxing factor [EDRF]) that relaxes smooth muscle cells in response to some vasodilating agents such as acetylcholine. Contraction curves to norepinephrine (NE) in greyhound, mongrel dog, and pig coronary artery rings were studied in vitro in the presence of propranolol. Removal of endothelium increased the sensitivity and maximum contraction in response to NE. In other experiments pig coronary rings were precontracted with a thromboxane mimetic U 46619 in the presence of propranolol. NE relaxed these arteries only if endothelium was present. Methoxamine was without effect but the relaxation response to NE was antagonized by phentolamine, idazoxan, and yohimbine, which suggests that there are alpha 2 adrenoceptors on endothelial cells that mediate the release of EDRF. Greyhound and mongrel dog large coronary arteries relaxed to NE only if prazosin was present, which suggests that alpha 1-adrenoceptor stimulation on the vascular smooth muscle can override the relaxation response to EDRF. Comparison of NE responses in carotid, mesenteric, renal, and femoral large arteries of the pig, greyhound, and mongrel dog indicate the nonuniformity of distribution of alpha 2 adrenoceptors on endothelium and alpha 1 and alpha 2 adrenoceptors on vascular smooth muscle. The integrity of the endothelium must now be considered in interpreting the vascular responses to alpha-adrenoceptor agonists.

Animals↗