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Biomedical subjects

K Satoh

Publications and source records attributed to K Satoh.

At least 991 records · Page 55Linked to original sources

Aesthetic camouflage of bilateral cleft lip scars.

Two operative scar lines remain after bilateral cleft lip repair. A method has been devised in which the two scar lines are reduced into one. The characteristics of this method include (1) an inconspicuous scar, (2) elevation of the nasal tip using the prolabium, (3) repair of the whistling deformity, (4) a natural-looking mustache, (5) formation of a pout, and (6) psychological benefits. Good results have been obtained with this method. The disadvantage of this method is the maxillary retardation. However, this does not occur in adults and can be corrected easily in children.

Adolescent↗

Cardiac and coronary vasodilator profile of pimobendan, a new cardiotonic drug, revealed by use of isolated, blood-perfused dog heart preparations.

Cardiac and coronary vasodilator effects of pimobendan (UD-CG 115 BS) were assessed in isolated, blood-perfused papillary muscle, sinoatrial (SA) node, and atrioventricular (AV) node preparations of dogs. Pimobendan was administered intra-arterially. In paced papillary muscle preparations, the drug increased the force of contraction in a dose-dependent manner. In SA node preparations, the drug produced an increase in sinus rate. When the drug was injected into the artery supplying the AV node, the drug produced a decrease in AV conduction time by accelerating AV nodal conduction in AV node preparations. In spontaneously beating papillary muscle preparations, the drug increased the rate of ventricular automaticity. No ventricular arrhythmias were produced by the drug. In all preparations, the drug increased (coronary) blood flow. The order of effectiveness of pimobendan on the above cardiovascular variables was as follows: ventricular muscle contraction much greater than coronary blood flow greater than SA nodal automaticity greater than AV nodal conduction greater than ventricular automaticity. The results indicate that pimobendan is relatively specific for force and its cardiovascular profile is very similar to those of phosphodiesterase inhibitors. Therefore, it is likely that this cardiovascular profile would be determined by its inhibitory action on phosphodiesterase.

Animals↗

Acid glycosaminoglycans in experimental pleural effusions.

Acid glycosaminoglycans (GAG) were quantitated and partially characterized in pleural effusions in guinea pigs with experimental allergic pleurisy. Increase of GAG in the pleural effusion preceded the increase of effusion volume. Effusion was associated with the presence of cuboidal mesothelial cells on visceral pleura, and hemorrhage, infiltration of neutrophils, and destruction of the alveolar structure of the lung. A significant difference was found in the relative percentage of GAG subtypes in the effusion, serum, and the lung tissue of guinea pigs with experimental pleurisy. There was a difference in molecular size of hyaluronic acid in pleural effusion between the early and late stages of pleurisy. Presumably GAGs found in pleural effusion were released from the pleural tissue.

Animals↗

Isolation and characterization of a mucin-type glycoprotein from the lung lavage of a patient with alveolar proteinosis.

A high molecular weight glycoprotein was isolated from the lavage fluid of a patient with alveolar proteinosis by gel chromatography with Sepharose CL-4B. The glycoprotein gave a single band stainable with alcian blue and with periodate-Schiff reagent on the cellulose acetate membrane electrophoresis. The glycoprotein did not penetrate 3.3% polyacrylamide gel but moved into 1% agarose gel as a periodate-Schiff positive single band, when electrophoresed in the presence of sodium dodecyl sulfate. The chemical analysis and the results of the beta-elimination reaction showed the presence of O-linked carbohydrate chains characteristic for a mucin-type glycoprotein. These data provide the first characterization of a mucin-type glycoprotein isolated from lung in pulmonary alveolar proteinosis.

Amino Acids↗

Piperidine: a microelectrophoretic study in the mammalian brain.

Using unit recording and electrophoretic techniques, the action of piperidine on unit activity of the brain of the rat was studied. Piperidine excited 31%, and inhibited 4% of cortical cells tested. In the hippocampus and caudate nucleus, piperidine excited larger proportions of the cells tested. The actions of piperidine were blocked by tetraethylammonium but not by scopolamine.

Acetylcholine↗

Inversion of enantioselectivity in glutathione conjugation of 9,10-dihydrobenzo[a]pyrene 7,8-oxide in hepatic cytosol of rats following induction of hepatic hyperplastic nodules by chemical carcinogens.

Enantiomers of 9,10-dihydrobenzo[a]pyrene 7,8-oxide (DBPO) were stereoselectivity conjugated with glutathione (GSH) specifically at benzylic carbon (C7) in normal Sprague--Dawley (SD) rat liver cytosol: (7R,8S)-(+)- greater than (7S,8R)-(-)-DBPOs. In contrast, in liver cytosol of SD rats bearing hepatic hyperplastic nodules induced with chemical carcinogens, (7S,8R)-(-)-DBPO was preferentially conjugated with GSH to (7R,8S)-(+)-DBPO. GSH S-transferases (GSTs) having sub-unit protein 4 were strongly suggested to play an important role in the preferential conjugation of (7R,8S)-(+)-DBPO in the normal rat liver cytosol, while the preferential conjugation of (7S,8R)-(-)-DBPO in the liver cytosol of the rat bearing hepatic hyperplastic nodules, was most likely to be attributable to GST 7-7, a characteristically induced protein in the hepatic hyperplastic nodules.

Animals↗

Isolation of a photosystem II reaction center consisting of D-1 and D-2 polypeptides and cytochrome b-559.

A photosystem II reaction center complex consisting of D-1 and D-2 polypeptides and cytochrome b-559 was isolated from spinach grana thylakoids, treated with 4% (wt/vol) Triton X-100, by ion-exchange chromatography using DEAE-Toyopearl 650S. The isolated complex appears to contain five chlorophyll a, two pheophytin a, one beta-carotene, and one or two cytochrome b-559 heme(s) (molar ratio) and exhibits a reversible absorbance change attributable to the photochemical accumulation of reduced pheophytin typical for the intermediary electron acceptor of photosystem II reaction center. These results strongly suggest that the site of primary charge separation in photosystem II is located on the heterodimer composed of D-1 and D-2 subunits.

Journal Article↗

Single GST-P positive liver cells--putative initiated hepatocytes.

Immunohistochemical investigation of liver tissue 48 h after single doses of the hepatocarcinogens diethylnitrosamine (DEN), dimethylnitrosamine, aflatoxin B1 and methylazoxymethanol acetate revealed the generation of a population of single glutathione S-transferase placental form (GST-P) positive hepatocytes. Yield was carcinogen dose dependent. Although the mixed function enzyme inducers sodium phenobarbital (PB), methylcholanthrene (Mech), polychlorinated biphenyls (PCB) and isosafrole (IS) did not in themselves induce comparable single cell lesions, their application prior to DEN caused significant alteration in the resultant numbers of GST-P positive hepatocytes observed. While PB and IS were associated with decreased yield, Mech and PCB, in contrast, brought about an increase. The results gained from investigation of the effects of 3-aminobenzamide administration and partial hepatectomy carried out at different times after carcinogen treatment also pointed to an 'initiated' character for the lesions and suggest that GST-P may be a useful marker for analyzing factors relevant to the initiation stage of hepatocarcinogenesis. Thus the interplay between carcinogen metabolism, DNA adduct formation and repair, toxicity and proliferation may be assessable in terms of numbers of enzyme-altered solitary hepatocytes.

Animals↗

Immunohistochemically demonstrated altered expression of cytochrome P-450 molecular forms and epoxide hydrolase in N-ethyl-N-hydroxyethylnitrosamine-induced rat kidney and liver lesions.

A comparison of N-ethyl-N-hydroxyethylnistrosamine (EHEN)-induced preneoplastic and neoplastic lesions in the rat liver and kidney was made with respect to the expression of different drug metabolizing enzymes. Four cytochrome P-450 species (cyt. P-450 UT50, PB3a, MC1 and MC2) and microsomal epoxide hydrolase (mEHb) were investigated along with two glutathione S-transferase species (GST-P and A forms) earlier shown to be elevated in putative preneoplastic lesions in the liver and kidney, respectively. In contrast to the liver lesions, which showed clear decrease in all forms of cyt. P-450s and increase of mEHb, elevated levels of cyt. P-450 PB3a and, to a lesser extent, the other P-450 forms and early elevation to late decrease in mEHb characterized the renal tubular lesions. Thus opposite shift in enzyme phenotype was observed in carcinogen-induced focal lesions of the two organs. Variation in binding levels in the different nephron segments and zones of the liver acinus indicated physiological specialization with regard to the enzymes investigated and suggested that the altered phenotype of preneoplastic populations might be of adaptive significance.

Animals↗

Comparison of vasodilator effects of DN-9693, a selective inhibitor of cyclic AMP phosphodiesterase, and isobutylmethylxanthine, a non-selective one, in dogs.

The present experiments were performed in anesthetized dogs in order to determine if DN-9693, a new antiplatelet agent known to selectively inhibit cyclic AMP phosphodiesterase (PDE), and isobutylmethylxanthine (IBMX), which inhibits both cyclic AMP and GMP PDEs, have different cardiovascular actions. With intra-arterial administration into the left anterior descending coronary, femoral, cranial mesenteric and renal arterial beds perfused at constant pressure with autologous blood, both agents increased blood flow in a similar dose range. DN-9693 was longer-acting than IBMX. Both agents were nearly equi-effective in the femoral circulation, but DN-9693 was 1.5-2 times less effective than IBMX in the others. With intravenous administration, both agents were equi-effective in increasing the maximum rate of rise of left ventricular pressure heart rate and myocardial oxygen consumption and in reducing mean blood pressure. However, DN-9693 was less effective in increasing coronary sinus outflow than IBMX. These results suggest the following: 1) Vasodilation in the somatic rather than the visceral circulation is important in reducing mean blood pressure. 2) Cyclic GMP may not be involved in the cardiac action of PDE-inhibitors. 3) Cyclic GMP may be involved in the vasodilator effect of PDE-inhibitors in the coronary, mesenteric and renal circulations but least involved in the femoral circulation.

1-Methyl-3-isobutylxanthine↗

The inhibitory effect of cytosolic fraction of human decidua on prostaglandin synthesis.

To elucidate the mechanism of suppression of prostaglandin (PG) production in decidua in early pregnancy, the PG synthetase activity of decidua and mid-secretory endometrium was studied. The microsomal fractions and their supernatants were prepared from the tissue by ultracentrifugation at 105,000 g. The standard incubation mixture consisted of the microsomal fraction and 14C arachidonic acid with cofactors, with incubation being carried out for 10 minutes at 37 degrees C. After extraction, the radioactivity of PGE2 was measured and PG synthetase activity was assayed. The apparent Km value for PG synthetase in decidua was 4.6 +/- 0.14 x 10(-6) M (n = 4), whereas that in endometrium was 4.6 +/- 1.18 x 10(-6) M (n = 3). Subsequently, kinetic studies on PG synthetase inhibitor in decidua were carried out. When sheep seminal vesicle was used as an enzyme source, the decidual supernatant showed competitive inhibition. The inhibitory substance in decidua was inactivated after incubation for 15 minutes at 65 degrees C. It seems likely that the suppression of PG biosynthesis in human decidua in early pregnancy is not due to the difference in PG synthetase found in decidua and in endometrium, but due to the existence of PG synthetase inhibitor in decidua.

Cell Extracts↗

[Evaluation of pN factors in patients with primary lung cancer by using perfusion, inhalation and ventilation studies].

The interpretation of scintigraphic patterns and the role of pathophysiological mechanisms in patients with primary lung cancer were investigated. To determine the relative roles of perfusion, inhalation and ventilation scintigraphy, the relationship between the count ratio of the affected side to the healthy side and the post-surgical histological lymph nodes factors were observed in this study. These scintigraphic count ratio's in patients with primary lung cancer did not reflect the pN factors except in the perfusion study in patients with hilar primary lung cancer.

Humans↗

[Enzyme alterations during chemical hepatocarcinogenesis].

Biochemical phenotypes such as the forms of enzyme proteins alter during the promotion and progression stages in chemical hepatocarcinogenesis. Many enzymes or isoenzymes have been identified as markers of (pre) neoplastic hepatic tissues and used for analysis of the carcinogenic process. The levels of hepatic isoenzymes decrease and those of prototypic or fetal isozymes increase during the progression of hepatocarcinogenesis. Some drug-metabolizing enzymes are also very variable at the promotion stage in rat chemical carcinogenesis; Phase I enzymes such as cytochrome P-450 decrease and Phase II (iso)-enzymes such as UDP-glucuronyl-transferase, glutathione S-transferase (GST) and gamma-glutamyl transpeptidase (gamma-GTP) increase. A new neutral GST form with pI 7.0 (GST-P) has been identified by us as one of the best markers for rat chemical hepatocarcinogenesis. GST-P is a homodimer consisting of a subunit (Mr 26,000, more accurately 23,307, and pI 6.7), the smallest among rat GST subunits, and differs immunochemically from any other GST form. It is present in very low levels in normal rat liver and is not inducible by most drugs including carcinogens without the appearance of preneoplastic hepatocyte nodules (HN) but it is increased by several ten-fold in HN-bearing liver and hepatomas induced by different carcinogens. Immunohistochemically, it is localized in HN and very early and small GST-positive foci are detectable using anti-GST-P antibody. (Pre) neoplastic hepatic lesions induced by nongenotoxic carcinogens such as hypolipidemic peroxisome-proliferating agents do not express GST-P as well as gamma-GTP.

Animals↗

Spontaneous in vitro production of thyroglobulin specific helper factor in patients with autoimmune thyroid diseases.

We have investigated regulatory cell abnormalities in patients with autoimmune thyroid diseases through in vitro thyroglobulin (Tg) specific helper factor production. Helper activities were measured in the mice spleen cell assays, using hapten-carrier system. Peripheral blood leukocytes (PBL) from 5 out of 6 patients produced the Tg specific helper factor not only when they were stimulated in vitro with Tg but also when they were not stimulated. On the contrary, normal PBL did not produce the factor when they were not stimulated in vitro. However, 3 out of 5 normal PBL did produce the factor when they were stimulated in vitro with Tg. From several lines of studies, this helper factor was specific for Tg in its production and action. From these results it is concluded that (a) Tg specific helper T cells are already activated in vivo in patients with autoimmune thyroid diseases, indicating the presence of immunoregulatory abnormalities in these patients, and that (b) normal PBL have a potential to produce this helper factor when they are appropriately stimulated.

Biological Assay↗

Comparison of the inhibitory effects of cilostazol, acetylsalicylic acid and ticlopidine on platelet functions ex vivo. Randomized, double-blind cross-over study.

A randomized double-blind cross-over study was conducted to determine the inhibitory effects of acetylsalicylic acid (ASA), ticlopidine (TP) and cilostazol (OPC-13013; in the following briefly called CS), a new antithrombotic agent on platelet functions ex vivo. Nine patients with cerebral thrombosis were enrolled in this study. Patients were given each of the three drugs for one week in a complete cross-over design according to a randomization schedule, followed by a wash-out period with a placebo for one week. It was found that CS and TP significantly inhibited platelet aggregation induced by ADP. Collagen- and arachidonic acid-induced platelet aggregation was all inhibited by CS, TP and ASA. Duncan's multiple range test to compare the anti-platelet effects of the three drugs revealed that: CS greater than ASA and TP greater than ASA in inhibiting ADP-induced platelet aggregation and CS greater than TP and ASA greater than TP in inhibiting arachidonic acid-induced platelet aggregation. These results may suggest that CS is superior to ASA and TP in inhibiting platelet aggregation ex vivo.

Aged↗

[A study on the activity of the PGI2 producing enzyme system derived from maternal and fetal vessels of toxemia of pregnancies].

We investigated the conversion rate from arachidonic acid (A.A.) to PGI2 and the activity of PGI2 producing enzyme system in endothelial cells of umbilical veins (U.V.) and maternal omental veins (O.V.) in normal pregnancy (NOR) and toxemia of pregnancy (TOX). The conversion rate from A.A. to PGI2 for U.V. and O.V. in NOR was higher than that in TOX. There was a significant difference between NOR and TOX with the conversion rate for U.V. at a concentration of 172.4 nM/ml A.A. The apparent Vmax value for PGI2 producing enzyme system (nM/mg) in U.V. in NOR (n = 7) was 0.88 +/- 0.21 (mean +/- S.E.) and that for TOX (n = 3) was 1.63 +/- 0.18. The apparent Km value for the enzyme system (microM) in U.V. in NOR (n = 7) was 0.75 +/- 0.25, and that for TOX (n = 3) was 3.26 +/- 0.78. Significant differences (p less than 0.05) between NOR and TOX were observed with Vmax and Km values. The apparent Vmax value for the enzyme system in O.V. in NOR (n = 3) was 0.32 +/- 0.13, and that for TOX (n = 3) was 2.12 +/- 0.38. The apparent Km value for the enzyme system in O.V. of NOR (n = 3) was 0.26 +/- 0.06, and that for TOX (n = 3) was 0.97 +/- 0.09. There was a significant difference between (p less than 0.05) the Vmax and Km values for NOR and TOX. The present study showed that U.V. (fetal vessel) and O.V. (maternal vessel) in TOX had a lower activity PGI2 producing enzyme system than those in NOR due mainly to an imbalance between the substrate supply and cyclooxygenase activity.

Adult↗