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Biomedical subjects

K Koike

Publications and source records attributed to K Koike.

At least 181 records · Page 10Linked to original sources
PubMed1999

Two new triterpenoid saponins from Platycodon grandiflorum.

Two new triterpenoid saponins, platycoside D [3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl-(1-->6)-beta-D- glucopyranosyl-2 beta, 3 beta, 16 alpha, 23-tetrahydroxyolean-12-ene-28-oic acid 28-O-beta-D- apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnop yranosyl- (1-->2)-alpha-L-arabinopyranoside] and platycoside E [3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl- (1-->6)-beta-D-glucopyranosyl-2 beta,3 beta,16 alpha,23,24-pentahydroxyolean-12-ene-28-oic acid 28-O-beta-D-apiofuranosyl-(1-->3)-beta-D-xylopyranosyl-(1-->4)-alp ha-L- rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside] were isolated from the roots of Platycodon grandiflorum. Structural determination is based on spectral and chemical evidence.

Carbohydrate Sequence↗
PubMed1999

[Pharmacological analysis of atypical beta-adrenoceptors in the guinea pig gastrointestinal tissue systems].

The purpose of the present study was to characterize the atypical beta-adrenoceptors involved in relaxant responses in guinea pig gastric fundus, duodenum and ileum in functional experiments with catecholamines (isoprenaline, noradrenaline and adrenaline), beta 3-adrenoceptor agonists (BRL37344 and CGP12177A) and a non-selective beta 1-, beta 2- and beta 3-adrenoceptor antagonist bupranolol, and to obtain further evidence to clarify whether there is a tissue difference in atypical beta-adrenoceptors in the guinea pig gastrointestinal tissue systems. The atypical beta-adrenoceptors are present in gastric fundus, duodenum and ileum of guinea pig. In the presence of propranolol (1 microM) or atenolol (100 microM) plus butoxamine (100 microM), bupranolol caused a concentration-dependent rightward shift of the concentration-response curves for catecholamines and beta 3-adrenoceptor agonists. There was not a significant difference of pA2 values for bupranolol against these agonists between gastric fundus, duodenum and ileum of guinea pig. These results suggest that guinea pig gastric fundus, duodenum and ileum relaxation are mediated predominantly by an atypical beta-adrenoceptor population whereas the classical beta 1- or/and beta 2-adrenoceptors play a subordinate function role and that the receptors of three tissues are pharmacological identified by functional approaches. There is not a tissue difference in atypical beta-adrenoceptors in the guinea pig gastrointestinal tissue systems between stomach and ileum.

Adrenergic beta-Agonists↗
PubMed1999

[The effects of fish supplementation of platelet function, count and metabolism in healthy Japanese].

To investigate changes in platelet function, count and metabolism following fish intake among Japanese, we conducted an experimental intervention study of seven healthy Japanese volunteers (4 males and 3 females) aged 28-58 years. We supplemented their diets with an approximate daily intake of 200-400 g fish which is equivalent to about 10 g n3-polyunsaturated fatty acids (about 3.5 g eicosapentaenoic acid plus 5.0 g docosahexaenoic acid) during the 17 days. The study continued until the 23rd day after returning to an ad libitum diet. The proportion of serum n3-polyunsaturated fatty acids increased two-fold on 5th day and three-fold on 15th day of fish supplementation, but decreased to one and a half-fold on the 2nd day and returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The proportion of serum n6-polyunsaturated fatty acids decreased by 17% to the level before fish supplementation on the 5th day, 33% on the 15th day of fish supplementation. However, the decrease was only 10% on the 2nd day and the proportion returned to the same level as before fish supplementation on the 12th day after returning to an ad libitum diet. As a result, the serum n3/n6 polyunsaturated fatty acid ratio increased four-fold on the 15th day of fish supplementation, and returned to the baseline level on the 12th day after returning to an ad libitum diet. Platelet counts decreased and the mean platelet volume increased during fish supplementation. Both parameters returned to the level before fish supplementation on the 12th day after returning to an ad libitum diet. The counts and proportion of large type platelets increased significantly during fish supplementation. Although platelet aggregation by ADP (adenosine 5'-diphosphate) did not change significantly, platelet aggregation by collagen tended to decrease during fish supplementation. Platelet factor 4, one of the indices of platelet activity, decreased significantly during fish supplementation. The mean serum triglyceride level declined during fish supplementation, but returned to the level just before fish supplementation on the 2nd day after returning to an ad libitum diet. The mean plasma fibrinogen level tended to decline during fish supplementation and remained lower until the 12th day after returning to an ad libitum diet. Habitual fish intake may attenuate the development of atherosclerosis and prevent ischemic heart disease through suppression of platelet activity, and by reducing platelet counts and serum triglyceride levels.

Adult↗
PubMed1999

Purification and properties of a low-molecular-weight, high-alkaline pectate lyase from an alkaliphilic strain of Bacillus.

A low-molecular-weight, high-alkaline pectate lyase (pectate transeliminase, EC 4.2.2.2) was found in an alkaline culture of Bacillus sp. strain KSM-P15, purified to homogeneity, and crystallized. The enzyme had a relative molecular weight of approximately 20,300 as measured by sedimentation equilibrium, with a sedimentation coefficient (s20,w0) of 1.73 S. It was a basic protein with an isoelectric point of pH 10.3, and the alpha-helical content was only 6.6%. In the presence of Ca2+ ions, the enzyme degraded polygalacturonic acid in a random manner to yield 4,5-unsaturated oligo-galacturonides and had its optimal activity around pH 10.5 and 50-55 degrees C. It also had a protopectinase-like activity on cotton fibers. The N-terminal amino acid sequences of the intact protein (28 amino acids) and its two lysyl endopeptidase-cleaved peptide fragments (8 and 12 amino acids) had very low sequence similarity with pectate lyases reported to date. These results strongly suggest that the pectate lyase of Bacillus sp. strain KSM-P15 may be a novel enzyme and belongs in a new family.

Amino Acid Sequence↗
PubMed1999

Peripheral arterial coil embolization for hepatic arteriovenous malformation in Osler-Weber-Rendu disease; useful for controlling high output heart failure, but harmful to the liver.

A 55-year-old Japanese housewife, who had Osler-Weber-Rendu disease, was admitted to our hospital because of frequent epistaxis and worsening exertional dyspnea. The computed tomography and hepatic arteriography revealed large hepatic arteriovenous malformation, which was considered to be the leading cause of her high output heart failure. Two series of hepatic arterial coil embolization procedures were performed to reduce hepatic shunt flow. They temporarily improved her cardiac condition, but gradually induced progressive hepatic failure due to intrahepatic cholangitis. Hepatic dysfunction restricted her quality of life and lead to a fatal clinical course one year after the second coil embolization.

Arteriovenous Malformations↗
PubMed1999

[Single-dose and high-volume Bretschneider cardioplegic solution for congenital heart surgery].

Bretschneider cardioplegic solution is used widely in Europe. The aim of this study is to investigate the efficacy of Bretschneider cardioplegic solution for open heart surgery of congenital heart disease in comparison with blood cardioplegia. From June 1995 to July 1997, we treated 32 congenital heart disease patients using Bretschneider cardioplegic solution and 20 patients using blood cardioplegia. Hospital mortality, water balance during operation, percentage of arrhythmia, and intubation time were not significant in both group. Also CPK and CPK-MB were not significant in both group. Bretschneider cardioplegic solution had preserved the heart as same as blood cardioplegia. This is a very convenient method so that we can use only one time infusion.

Cardiac Surgical Procedures↗
PubMed1999

[Co-infection of HBV with HCV and a possible role of HBV DNA in hepatocarcinogenesis].

HBV and HCV are two major etiologic agents of chronic hepatitis, which is closely related to the development of hepatocellular carcinoma (HCC). A possible involvement of HBV co-infection was investigated in ongoing HCV-related liver diseases in HCV-infected patients. A high prevalence of anti-HBC in anti-HCV-positive/HBsAg-negative chronic hepatitis patients was found and a low copy number of HBV DNA was detected in most of the liver biopsy samples of anti-HCV-positive/HBsAg-negative patients. The current data suggest that HBV co-infects frequently with HCV and may play an important role in the development of HCC in HCV-infected patients.

Carcinoma, Hepatocellular↗
PubMed1999

[Infant leukemia with t(1;22) presenting proliferation of erythroid and megakaryocytic cell lineages].

We report a case of infant leukemia with the proliferation of both erythroblast and megakaryoblast lineages. The blasts became double-positive for both erythroblastic and megakaryoblastic surface markers at the time of bone marrow relapse. A 9-month-old girl was admitted to our hospital presenting chiefly poor with weight gain and anemia. She also had splenomegaly, pleural effusion, leukocytosis, and thrombocytopenia. A bone marrow specimen showed 53.2% erythroblasts (PAS positive, alpha-NA positive, CD41 negative, MPO negative) and 20.4% megakaryoblasts with marked cytoplasmic blebs. We examined specimens by two-color flow cytometric analysis. At the onset, CD41+ glycophorin A- fraction and CD41- glycophorin A+ fraction were two major components. At the bone marrow relapse, the majority of blasts had altered to double-positive. Chromosomal analysis showed t (1; 22) (p13; q13), which has been reported to be specific for acute megakaryoblastic leukemia (M7) in infants. We reasoned that a leukemia had occurred in this patient at a progenitor cell level common to both erythroid and megakaryocytic lineages.

Bone Marrow Cells↗
PubMed1999

Autologous high-killing cytotoxic T lymphocytes against human lung cancer are induced using interleukin (IL)-1beta, IL-2, IL-4, and IL-6: possible involvement of dendritic cells.

Although CTLs bear main immune responses in human tumors, stable CTL clones against human lung cancer have rarely been generated. Our previous study demonstrated efficient autologous CTL induction in human gastric cancer and glioblastoma by cytokine combination of interleukin (IL)-1beta (167 IU/ml), IL-2 (67 IU/ml), IL-4 (67 IU/ml), and IL-6 (134 IU/ml). In this study, we demonstrated successful induction of autologous stable CTLs in five of six patients with lung adenocarcinoma from mixed-lymphocyte tumor culture using this cytokine combination. All CTLs revealed potent and specific killing activity against autologous target cells (over 75% in CD8+ CTLs and over 50% in CD4+ CTLs at an E:T ratio of 10 for 24 h). Using a series of antibodies, CD8+ CTLs showed to recognize tumor-specific antigens of lung cancer cells through HLA class I. In the separate experiments, failure of CTL induction from monocyte-depleted peripheral blood mononuclear cells and appearance of cells with characteristics of dendritic cells from adherent peripheral blood mononuclear cells in the culture of the same concentration of IL-1beta, IL-4, and IL-6 indicated that CTLs can be efficiently generated by this cytokine combination via possible dendritic cell induction. This is the first study of an efficient and reproducible in vitro CTL induction against human lung cancer.

Adenocarcinoma↗
PubMed1999

Lupus nephritis in juvenile myelomonocytic leukemia.

A 13-year-old girl developed lupus nephritis and Hashimoto thyroiditis in the chronic phase of juvenile myelomonocytic leukemia (JMML). At age 7 months, she was diagnosed as having JMML based on the hepatosplenomegaly, leukocytosis, thrombocytopenia, increased levels of fetal hemoglobin, and spontaneous in vitro growth of granulocyte-macrophage progenitors. At the onset of JMML, she had hypergammaglobulinemia, antinuclear antibodies, rheumatoid factors and anti-smooth muscle antibody. She had been placed on oral 6-mercaptopurine for about 12 years, with clinical improvement. At age 13 years, she was found to have hematuria and proteinuria. She also developed arthritis and Raynaud's phenomenon as well. She had antinuclear antibodies, rheumatoid factors, LE phenomenon, beta-1C (C3) nephritic factor (C3NeF), antithyroid antibodies, and hypocomplementemia. The renal biopsy specimens revealed a diffuse increase in the mesangial cells and matrix by light microscopy, and intense staining of IgG, Clq and C3 by immunofluorescence microscopy. The hormonal study ultimately showed decreased thyroid functions. So she was diagnosed as lupus nephritis and Hashimoto thyroiditis. The patient is the first example to show close relationship between stem cell abnormalities in JMML and development of overt autoimmune disorders.

Adolescent↗
PubMed1999

[Splanchnic hypoperfusion and distant organ injury].

Acute respiratory distress syndrome (ARDS) and multiple organ failure (MOF) are the most common causes of death in surgical intensive care units. A variety of stimuli, such as major surgery, trauma, shock, thermal injury, acute pancreatitis, and ischemia-reperfusion injury, initiate a systemic inflammatory response that contributes to the development of these complications. Splanchnic hypoperfusion is a common clinical event in critically ill patients. Recently, measurement of the adequacy of gut circulation has been demonstrated as an excellent tool for prediction of outcome in these patients. The emphasis of this review is on events associated with intestinal ischemia-reperfusion and subsequent distant organ injury.

Cytokines↗
PubMed1999

[The value of intracellular CD41 antigen detection to the diagnosis of acute megakaryoblastic leukemia].

An 11-month-old boy was transferred to our hospital because of fever and bleeding tendency on March 13, 1998. Laboratory studies showed a white blood cell count of 43,360/microliter with 75% blasts, a hemoglobin concentration of 8.4 g/dl, and a platelet count of 23 x 10(3)/microliter. Surface marker analysis with a flow cytometer revealed that only 21% and 11% of the blasts, respectively, were positive for CD41 and CD42b. Treatment with a permeabilizing agent apparently increased the reactivity of the blasts with anti-CD41 monoclonal antibody (MoAb), which can recognize IIb independently of IIIa. However no significant differences were observed in reactivity with anti-CD41 MoAb (which recognizes the IIb/IIIa complex) anti-CD61 MoAb and anti-CD42b MoAb before or after fixation. Blasts positive for platelet peroxidase were observed by electron microscopy, thus confirming the diagnosis of acute megakaryoblastic leukemia. We concluded that the detection of intracellular antigens is useful for the quick diagnosis of acute megakaryoblastic leukemia characterized by low surface expression of megakaryocytic lineage antigens.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

[Determination of lignan glycosides in the roots of Gaultheria yunnanensis Rehd. by HPLC].

OBJECTIVE: To determine the contents of four lignan glycosides in the root of Gaultheria yunnanensis, namely, D1: gaultheroside A, D2:(-)-8'-methoxyisolariciresinol-2a-O-beta-D-xylopyranoside, D3:(-)-isolariciresinol-2a-O-beta-D-xylopyranside, D4:(+)-lyoniresinol-2a-O-beta-D-glucoxylopyranoside. METHOD: Rp-HPLC was used to separate and analyze the lignan glycosides in the root of the title plant. RESULT: The method for sample preparation was set up; the gradient program for the mobile phase was established; and the retention times of four lignan glycosides were determined. CONCLUSION: The method has been proved to be accurate, reproducible and of higher recovery rate.

Chromatography, High Pressure Liquid↗
PubMed1998

Compensatory apoptosis in preneoplastic liver of a transgenic mouse model for viral hepatocarcinogenesis.

The HBx protein of hepatitis B virus has been shown to induce hepatocellular carcinoma in transgenic mice as direct evidence for its involvement in hepatocarcinogenesis. In these transgenic mice, however, it is not clear why hepatocytes do not acquire a neoplastic phenotype by 13 months old despite the continuous growth stimulation by the HBx protein from 2 months old. In this study, we show that the accelerated proliferation of hepatocytes is counterbalanced by apoptosis, which maintains liver homeostasis. A decrease in the extent of apoptosis seems to precede the emergence of neoplasia in the transgenic mouse liver. The disappearance or block of apoptotic signals, which may be the result of additional genetic or epigenetic aberrations, may result in the preneoplastic hepatocytes becoming neoplastic.

Aging↗
PubMed1998

Three-dimensional behavior of ice crystals and biological cells during freezing of cell suspensions.

Behavior of ice crystals and human red blood cells during extracellular-freezing was investigated in three-dimensions using a confocal laser scanning microscope(CLSM), which noninvasively produces tomograms of biological materials. Physiological saline and physiological saline with 2.4 M glycerol were used for suspension. Various cooling rates for directional solidification were used for distinctive morphology of the ice crystals. Addition of acridine orange as a fluorescent dye into the cell suspension enabled ice crystal, cells and unfrozen solution to be distinguished by different colors. The results indicate that the microscopic structure is three-dimensional for flat, cellular, and dendritic solid-liquid interfaces and that a CLSM is very effective in studying three-dimensional structure during the freezing of cell suspensions.

Blood Preservation↗
PubMed1998

Crystallization and preliminary X-ray analysis of pig E3, lipoamide dehydrogenase.

Pig heart lipoamide dehydrogenase was crystallized by the hanging-drop vapor-diffusion method. X-ray diffraction patterns show that the hexagonal crystals have unit-cell dimensions of a = b = 359. 3, c = 140.5 A. The crystal structure has been preliminarily solved by the molecular-replacement method in the space group P6322. Three dimeric molecules have been found in the asymmetric unit, one of them located on the crystallographic twofold axis.

Animals↗
PubMed1998

Cloning, structure, chromosomal localization and promoter analysis of human 2-oxoglutarate dehydrogenase gene.

Human 2-oxoglutarate dehydrogenase (OGDH) is an E1-component of the OGDH multi-enzyme complex and catalyzes both the ThDP-dependent decarboxylation of 2-oxoglutarate and the subsequent reductive succinylation of the lipoyl moiety which is covalently bound to the E2 component, dihydrolipoamide succinyltransferase. The cDNA and genomic DNA encoding human OGDH has been cloned and sequenced. The cDNA contains a 3006-bp open reading frame encoding a 40-amino acid leader peptide and a 962-amino acid mature OGDH protein (Mr=108878). The gene contains 22 exons spanning approximately 85 kb. The putative ThDP-binding sequence motif is identified in both DNAs. The gene is localized to chromosome 7 at p13-p14 by fluorescence in situ hybridization. With the TATA- and CAAT-less 5'-flanking region (wild type, -3276/+212) of the OGDH gene-luciferase reporter vector construct and its nested deletion or linker-scanning mutant constructs the transient reporter expression assays in BHK-21 cells reveal the existence of two 10-bp cis-acting elements (-53/-44 and -33/-24) and two trans-acting elements (-536/-496 and -93/-84). A nuclear factor that binds to the region from -63 to -24 including two cis-acting elements.

Amino Acid Sequence↗