PubMed Health⌕ Search

Biomedical subjects

K Satoh

Publications and source records attributed to K Satoh.

At least 19 recordsLinked to original sources
PubMed1992

Interaction of beta-eudesmol with Na+,K(+)-ATPase: inhibition of K(+)-pNPPase activity.

The effect of beta-eudesmol, one of the major components in So-jutsu (Atractylodis Lanceae Rhizoma), on K(+)-dependent p-nitrophenyl phosphatase (K(+)-pNPPase) activity was studied. It inhibited K(+)-pNPPase activity with an I50 value of 4.1 x 10(-4) M. The inhibition rate decreased as the K+ concentration was increased, whereas greater inhibition was observed with high concentrations of either Na+ or ATP. The Ki values for Na+ in the presence of 0, 0.1 and 1 mM ATP were 140, 260 and 310 mM, respectively, but with the addition of beta-eudesmol, these values decreased to 90 mM regardless of the ATP concentration. This study on K(+)-pNPPase activity supports the conclusion obtained from the study on Na+,K(+)-ATPase activity (Satoh K et al., Biochem Pharmacol 44: 373-378, 1992) that is, beta-eudesmol interacts with enzyme in the Na.E1 form and inhibits the reaction step Na.E1----Na.E1-P. Furthermore, in the study of the effects of K+ and beta-eudesmol on K(+)-pNPPase activity, it was confirmed that beta-eudesmol prevents the conformational change of Na.E1----K.E2.

4-Nitrophenylphosphatase↗
PubMed1992

Inhibition of Na+,K(+)-ATPase activity by beta-eudesmol, a major component of atractylodis lanceae rhizoma, due to the interaction with enzyme in the Na.E1 state.

beta-Eudesmol, a major component of the crude drug "So-jutsu" (Atractylodis Lanceae Rhizoma), inhibited Na+, K(+)-ATPase activity most strongly among the various kinds of phosphatases examined. It also inhibited Ca(2+)-ATPase and H+, K(+)-ATPase, but to a lesser extent. Its effect on Mg(2+)-ATPase was minute. No effects on H(+)-ATPase or alkaline and acid phosphatase activities were observed. The effects of beta-eudesmol on horse kidney Na+, K(+)-ATPase were studied in detail, and the following results were obtained: (1) beta-eudesmol inhibited the Na+, K(+)-ATPase activity with an I50 value of 1.6 x 10(-4) M. The mode of its inhibition was uncompetitive with respect to ATP; (2) it prevented the stimulation of enzyme activity by Na+. The inhibition gradually increased in accord with the increase of Na+ concentration, and it was constant when Na+ was higher than 6.3 mM; (3) it did not alter the K+ concentration necessary for half-maximal activation (K0.5 for K+); and (4) it inhibited the enzyme activity with a mode of action different from ouabain. Phosphorylation of enzyme with [gamma-32P]ATP was inhibited by beta-eudesmol with an I50 of 1.4 x 10(-4) M. The inhibition was greater in 1 M NaCl than in 0.1 M NaCl. It had no effects on dephosphorylation steps, i.e. none of the non-specific, the ADP-sensitive (Na.E1-P----Na.E1) and the K(+)-dependent (E2-P----K.E2) dephosphorylation processes were affected. These results suggest that beta-eudesmol, a relatively specific inhibitor of Na+, K(+)-ATPase, interacts with the enzyme in the Na.E1 form and inhibits the reaction step Na.E1----Na.E1-P.

Adenosine Triphosphatases↗
PubMed1992

Vasodepressor mechanisms of 2-(1-octynyl)-adenosine (YT-146), a selective adenosine A2 receptor agonist, involve the opening of glibenclamide-sensitive K+ channels.

The vasodepressor mechanism of 2-(1-octynyl)-adenosine (YT-146), a selective adenosine A2 receptor agonist, was compared with that of adenosine in spinally anaesthetized dogs whose blood pressure was kept elevated with i.v. infusion of noradrenaline. Cumulative i.v. administration of YT-146 (1-1000 nmol/kg) caused a slowly developing and long-lasting decrease in mean blood pressure (MBP) and a small decrease in heart rate (HR) at high doses, whereas single i.v. administration of adenosine caused short-lived decreases in MBP and HR. In dogs given glibenclamide (6 mumol/kg i.v.) or theophylline (30 mumol/kg i.v.) dose-response curves for decrease in MBP due to YT-146 underwent parallel rightward shifts. The ED50 values for YT-146 were increased about 5.5-fold with glibenclamide and about 11.9-fold with theophylline. However, no further rightward shifts of the curves were obtainable in dogs given glibenclamide plus theophylline; the increase in ED50 values for YT-146 was about 6.8-fold, being close to the increase obtained with theophylline alone. The ED50 values for adenosine to lower MBP increased about 1.6-fold with theophylline but not with glibenclamide. Glibenclamide and theophylline failed to antagonize the negative chronotropic effects of both drugs. These results suggest that the vasodepressor effect of YT-146 involves two mechanisms following stimulation of adenosine A2 receptors; one is probably a cyclic AMP-dependent mechanism and the other is the opening of glibenclamide-sensitive K+ channels.

Adenosine↗
PubMed1992

Accumulation of a translation intermediate of D1 protein by light-dark transition in isolated spinach chloroplasts.

In an in vitro translation experiment using spinach chloroplasts, a novel protein band of about 17.5 kDa appeared by light to dark transition. The protein never accumulated in detectable amounts either in continuous illumination or in continuous darkness. The 17.5 kDa protein accumulated upon light-dark transition, on the other hand, disappeared by the subsequent illumination. Accumulation of the protein in light, however, was observed when stromal level of ATP in chloroplasts was lowered after preillumination by the addition of various chemical compounds which, irrespective of the mode of action, eventually decrease the ATP level, e.g. atrazine, carbonyl-cyanide-m-chlorophenyl hydrazone and glycerate. The dark-accumulated protein was concluded to be a translation intermediate of D1 protein based on the facts that this component precipitates with specific antibodies and is resistant to lysylendopeptidase treatment. The suppression by chloramphenicol of both appearance upon light-dark transition and disappearance by the subsequent illumination of the protein also supported this conclusion. The phenomenon was discussed in terms of pausing in the translation of psbA mRNA.

Chloramphenicol↗
PubMed1992

Cloning of 67-kDa laminin receptor cDNA and gene expression in normal and malignant cell lines of the human lung.

Cell-adhesive protein laminin and its specific receptor play an important role in the processes of cancer proliferation, invasion and metastasis. In the present study, we cloned the cDNAs of the 67-kDa laminin receptor both from a human lung cell line (IMR90) and from a human lung cancer cell line (SBC3), and determined the nucleotide sequences. In comparison with both cDNA sequences of the protein-coding region, three nucleotide differences were found. These differences in the secondary structure of the protein, however, were caused by nucleotide substitutions. It was also demonstrated that the level of 67-kDa-laminin receptor mRNA was higher in SBC3 than in IMR90.

Amino Acid Sequence↗
PubMed1992

Type I congenital plasminogen deficiency is not a risk factor for thrombosis.

The risk of thrombosis in type I congenital plasminogen (PLG) deficiency has been suggested, but is still not confirmed. We studied 40 members of two unrelated families with this disease, and found that 21 were heterozygotes of type I congenital PLG deficiency. Three of them had thrombosis, but the other 18 had no thrombosis. The percentages of family members with no history of thrombosis up to a given age among subjects with type I congenital PLG deficiency and healthy controls were analyzed by the Kaplan-Meier method. No significant difference between the two groups was observed by the generalized Wilcoxon test (p = 0.23). These results suggest that there is no significant correlation between type I congenital PLG deficiency and thrombosis.

Adult↗
PubMed1992

Increased expression of the 67kDa-laminin receptor gene in human small cell lung cancer.

Gene expression of the precursor of the 67kDa-laminin receptor was examined by Northern analysis using 11 established human lung cancer cell lines and 25 lung cancer tissues obtained by operation. As a result, one transcript, the size of which was 1.2 kb was shown in all cell lines and tissues examined. An increased level of mRNA was demonstrated in cell lines which proliferated rapidly and in small cell lung cancer cell lines. It was also indicated that gene expression of the laminin receptor was up-regulated especially in small cell lung cancer tissue. In this context, 67kDa-laminin receptor appears to be a marker for biological aggressiveness of human lung cancer.

Adenocarcinoma↗
PubMed1992

Induction of glutathione S-transferase P-form in primary cultured rat liver parenchymal cells by co-planar polychlorinated biphenyl congeners.

Alterations in protein synthesis in primary cultured rat liver parenchymal cells were examined after their exposure to the potent carcinogens, polychlorinated biphenyl (PCB) congeners. Co-planar PCB congeners (3,4,5,3',4'-PCB and 3,4,5,3',4',5'-PCB) (10 nM) induced a protein, the Mr of which was 25,000 (25 k protein) under denaturing conditions. However, non-co-planar PCB congeners and several xenobiotics, which induce microsomal proteins, did not induce the 25 k protein. By using immunoblotting, the 25 k protein was identified as glutathione S-transferase P-form (GST-P, 7-7, EC 2.5.1.18).

Animals↗
PubMed1992

Activity of platelet-activating factor acetylhydrolase exists in red cell membrane.

We have described the intracellular type of platelet-activating factor acetylhydrolase (PAF-AH) in the membrane extract of human red blood cells (RBCs). The enzymatic activity was inhibited by diisopropylfluorophosphate, trypsin or pronase E, but not affected by EDTA or the addition of 1-O-hexadecyl-2-hexadecanoyl-rac-glycero-3-phosphocholine or 1-O-hexadecyl-2-[(cis)-9-octadecenoyl]-rac-glycero-3-phosphocholin e. The activity in 10 healthy volunteers was 3.89 +/- 3.26 pmol/10(9) RBCs/min (or 148 +/- 73 nmol/g protein/min) (mean +/- SD). Since PAF-AH is also known to hydrolyze oxidized derivatives of phosphatidylcholine and since RBCs are not effector cells of PAF, the observed activity in RBC membranes may play a potential role in degrading oxidation products of membrane phospholipids.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗
PubMed1992

Determination of enzyme activities of energy metabolism in the maturing rat oocyte.

Enzyme activities were determined quantitatively in individual rat oocytes to study their energy metabolism during maturation. Low hexokinase activity and high activities of lactate dehydrogenase and enzymes in the phosphate pathway, i.e., glucose 6-P and 6-P gluconate dehydrogenases, were characteristic of immature oocytes. Hexokinase may be a rate-limiting enzyme that enables oocytes to use glucose as an energy source. During maturation, the activities of hexokinase, phosphofructokinase, and malate dehydrogenase increased significantly, suggesting that the glycolytic pathway, as well as the tricarboxylic acid cycle, developed as the first meiotic division proceeded. In contrast, the activities of glucose 6-P and 6-P gluconate dehydrogenases decreased in maturing oocytes. The observation that the enzyme pattern in mature oocytes resembles more closely that in somatic cells appears to be significant, especially in light of previous studies showing this developmental trend in preimplantation embryos.

Animals↗
PubMed1992

Effectiveness of planar image and single photon emission tomography of thallium-201 compared with gallium-67 in patients with primary lung cancer.

A comparative study of planar images and single photon emission tomography (SPET) of thallium-201 chloride and gallium-67 citrate was performed in 38 patients with proven primary lung cancer to detect the primary lung tumour and to establish the presence of metastasis in the lung hilum and mediastinum. The findings of planar images and SPET were compared with the pathological findings after thoracotomy. It was shown that 201Tl studies were superior to 67Ga studies for evaluation of the primary lesion and lymph node metastases.

Aged↗
PubMed1992

Factors influencing the response and survival of patients with liver metastases from breast cancer receiving OK-432-combined adoptive immunotherapy.

The response and survival of 26 patients with liver metastases from breast cancer, who received OK-432-combined adoptive immunotherapy from 1984 to 1990, were evaluated. OK-432-combined adoptive immunotherapy was comprised sequential treatment via the hepatic artery with a streptococcal preparation, OK-432 (1-5 KE), and adoptive transfer of lymphocytes expanded in T-cell growth factor and sonicated tumor extract antigen. Seventeen (65%) patients responded to the therapy. The median survival time of all patients after treatment was 13 months (range, 2-63 months). Of the 20 prognostic factors analyzed, performance status (PS) alone was related to response (P less than 0.01). The response rate of the patients with a PS of 0-2 was 83% but only 25% in those with a PS of 3 or 4. In univariate analysis, 11 factors significantly influenced the survival: tumor response; size of primary tumor; menopausal status; PS; serum bilirubin, albumin, lactate dehydrogenase and glutamate-oxalate transaminase (aspartate aminotransferase); the extent of liver involvement; and the number and the proliferation rate of transferred lymphocytes. The MST was 22.8 months for the responders versus 2.8 months for the nonresponders (P less than 0.01). In multivariate analysis, the most important factor associated with survival was the tumor response, as well as PS, liver involvement, lactate dehydrogenase and albumin. These results suggest that OK-432-combined adoptive immunotherapy can be considered a candidate for a randomised control study and these factors should be used for stratification.

Breast Neoplasms↗
PubMed1992

Therapeutic and life-prolonging effect of intrapleural injection with a streptococcal preparation, OK-432, and IL2-cultured effusion lymphocytes to breast cancer patients with malignant pleural effusion.

We developed a local AIT using PEL cultured with TCGF combined with preadministration of OK-432. Twenty-six patients of breast cancer with pleural effusion have been treated with this therapy since 1983. PEL expanded and tumor cells collapsed by day 9 in culture with TCGF. Cultured PEL possessed significantly higher cytotoxic activity against autologous tumor cells than PBL cultured in the same condition (p less than 0.05), but there was no difference between their cytotoxic activities against K562. The proliferation rate of PEL obtained after intrapleural administration of OK-432 was higher than that obtained before OK-432 (p less than 0.01). Moreover, the cytotoxic activities against both autologous tumor and K562 of cultured PEL obtained after OK-432 administration was significantly (p less than 0.05) higher than those cultured PEL obtained before. Cultured PEL (1 x 10(8)-6 x 10(9)) were transferred into the pleural cavity after the intrapleural administration of OK-432 (1-5 KE). The volume of pleural effusion increased temporarily after the administration of OK-432 but significantly (p less than 0.01) decreased after AIT. Tumor cells disappeared cytologically in 22 patients at the last puncture of pleural effusion. Pleural effusion disappeared completely in 19 of 26 patients and decreased by more than 50% in volume in 6 patients. Performance status improved in 22 patients. The response rate for OK-432-combined AIT in the present study was 96%. The survival period of the patients treated by OK-432-combined AIT in this trial was significantly (p less than 0.002) prolonged compared to that of the patients receiving chemotherapy alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

A modified Le Fort I osteotomy for maxillofacial deformity: a preliminary report.

A new technique of Le Fort I osteotomy using a wedge-shaped bony incision is described. After forward mobilisation of the osteotomised maxilla, the bone graft is held firmly in contact under some compression between the maxilla and the mobilised wedged portion to achieve greater stability. This is a very effective technique for those maxillary osteotomies which need bone graft stabilisation, such as in cleft lip and palate patients.

Adolescent↗
PubMed1992

Growth rate of myelin figures for phosphatidylcholine and phosphatidylethanolamine.

The growth length of myelin figures (or myelin tubes) was measured for several kinds of phospholipids using optical microscopy. The measurements were done for myelin figures with various thickness of tube wall. In spite of remarkable differences in morphology between the myelin figures of phosphatidylcholine and those of phosphatidylethanolamine, the growth rates for both were adapted to the expression proposed previously. The initial rate and the damping factor of the growth were inversely proportional to the wall thickness of myelin tubes.

In Vitro Techniques↗
PubMed1992

Loss of peroxisomal enzyme expression in preneoplastic and neoplastic lesions induced by peroxisome proliferators in rat livers.

Immunohistochemical staining of enoyl CoA hydratase (ECH), a key peroxisomal enzyme, revealed that the putative preneoplastic lesions induced in livers by administration of the peroxisome proliferator (PP) clofibrate (0.3% in diet) to rats for 60 weeks or more, lacked this enzyme so that they could be detected as ECH-negative foci. ECH and other peroxisomal enzymes such as acyl CoA oxidase, catalase and carnitine-dependent acetyltransferase were also either not or only weakly expressed in most hepatic hyperplastic nodules and hepatomas induced by ciprofibrate (0.025% in diet), Wy-14,643 (0.1%) or BR-931 (0.2%), while being strongly induced in surrounding hepatocytes. These results indicate that the expression of ECH and other peroxisomal enzymes is repressed in putative preneoplastic and neoplastic lesions induced by PPs in rat livers and that these peroxisomal enzymes might therefore be used as negative markers.

Animals↗