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T Kaneda

Publications and source records attributed to T Kaneda.

At least 163 records · Page 9Linked to original sources
PubMed1991

Iso- and anteiso-fatty acids in bacteria: biosynthesis, function, and taxonomic significance.

Branched-chain fatty acids of the iso and anteiso series occur in many bacteria as the major acyl constituents of membrane lipids. In addition, omega-cyclohexyl and omega-cycloheptyl fatty acids are present in several bacterial species. These two types of fatty acids are synthesized by the repeated condensation of malonyl coenzyme A with one of the branched-chain and cyclic primers by the same enzyme system. The pathway of de novo branched-chain fatty acid synthesis differs only in initial steps of synthesis from that of the common straight-chain fatty acid (palmitic acid) present in most organisms. The cell membranes composed largely of iso-, anteiso-, and omega-alicyclic acids support growth of bacteria, which inhabit normal as well as extreme environments. The occurrence of these types of fatty acids as major cellular fatty acids is an important criterion used to aid identification and classification of bacteria.

Bacteria↗
PubMed1991

Treatment of torsade de pointes with intravenous magnesium in idiopathic long QT syndrome.

A middle aged woman with idiopathic long QT syndrome was found to have repetitive ventricular tachycardia of the "torsade de pointes" type. The arrhythmia was resistant to mexiletine and lidocaine, but was controlled by intravenous magnesium sulfate (MgSO4). The recurrent attacks were abolished by a bolus of 2.0 g MgSO4, and extremely prolonged QTU interval was reduced by intravenous infusion of 5 mg/min MgSO4 for 36 h. This case shows the effectiveness of intravenous magnesium in controlling the attack of torsade de pointes in patients with idiopathic long QT syndrome.

Adult↗
PubMed1991

Effects of nebracetam (WEB 1881 FU), a novel nootropic, as a M1-muscarinic agonist.

We here investigated the effects of nebracetam (WEB 1881 FU 4-aminomethyl-1-benzylpyrrolidin-2-one-hemifumarate), a novel pyrrolidinone nootropic, on the rise of intracellular Ca2+ concentration ([Ca2+]i) in Jurkat cells, a human leukemic T cell line. Nebracetam induced a rise of [Ca2+]i in the medium with 1 mM Ca2+ and without Ca2+ (plus 1 mM EGTA). The nebracetam-induced [Ca2+]i rise was blocked by atropine greater than pirenzepine greater than AF-DX 116. From these results, nebracetam seems to act as an agonist for human M1-muscarinic receptors.

Animals↗
PubMed1991

Langerhans cells in the developing mucosal epithelium of mice.

The presence of Langerhans cells in the developing mucosal epithelium of mice was investigated by ATPase histochemistry and by electron microscopy. In the stratified squamous epithelium of the tongue and forestomach, a few ATPase-positive Langerhans cells could be recognized at 1 or 2 weeks after birth. They increased in number by 3 weeks of age, but the density was lower than that in the epidermis. The ATPase-positive cells in the mucosal epithelium had longer (18-22 microns) dendritic processes; each cell thus occupied a large space. The mucosal Langerhans cell with elongated dendritic processes may well be responsible for the surveillance of a wide area in the defense system of the mucous membrane. The cells had a clear cytoplasm among keratinocytes in the basal cell layer and, under the electron microscope, showed characteristics similar to those of the epidermal Langerhans cells; Birbeck granules were also recognizable in the cytoplasm.

Adenosine Triphosphatases↗
PubMed1991

Differential lectin binding on walls of thoraco-cervical blood vessels and lymphatics in rats.

Lectin binding in the walls of large to medium-sized blood vessels and lymphatics in the rat thoraco-cervical region was examined histochemically. The tunica intima of the aorta and superficial cervical artery showed positive reactions with wheat germ agglutinin (WGA) and Concanavalin A (ConA) but not with Dolichus biflorus agglutinin (DBA). The tunica media of the aorta exhibited intense WGA binding, especially on the smooth muscle cells, but the tunica media of the superficial cervical artery did not react with the lectin. Neither ConA nor DBA bound to the tunica media of the aorta and superficial cervical artery. The tunica adventitia of both arteries contained sites binding the three lectins, although DBA reactivity declined as the vascular diameter decreased. The tunica intima of the superior vena cava and azygos vein exhibited positive WGA and ConA binding, whereas DBA binding was noted on only part of the tunica intima of the superior vena cava and not on that of the azygos vein. The tunica media and tunica adventitia were reactive for all three lectins. The WGA and ConA binding sites in the tunica adventitia showed loose networks, suggesting lectin binding on connective tissue elements interlacing among smooth muscle bundles. Lectin binding sites in the walls of lymphatics exhibited an arrangement similar to those in the walls of the veins. Moreover valves protruding into the lumen showed intense WGA and ConA binding and scattered DBA binding. Three other lectins (Ulex europaeus agglutinin, peanut agglutinin, Maclura pomifera) were examined, but they showed no reactions with the vessels. Thus, the differential binding of lectins on the walls of blood vessels and lymphatics of various sizes suggests the functional complexity of monosaccharide residues in the vascular walls.

Animals↗
PubMed1991

[Effect of plasma on analysis of lymphocyte subsets].

We examined the effect of plasma on the analysis of lymphocyte subsets with a flow cytometer using whole blood cells. Removal of plasma from whole blood by washing them before labelling the lymphocytes with fluorescein-conjugated antibodies reduced the proportion of CD5+CD19+ cells and increased the proportions of CD16+ CD57- and CD16+ CD57+ cells, as compared with those measured without washing, but did not change the proportions of CD5+ CD19-, CD5- CD19+, CD4+ CD8-, CD4- CD8+ and CD16- CD57+ cells. Removal of plasma from whole blood also reduced the fluorescence intensity of CD4 and CD5 antigens and increased that of CD8, CD16, CD19 and CD57 antigens on each lymphocyte subsets. Characteristics of the changed lymphocyte subsets were to have a surface antigen with weak immunofluorescence on the flow cytometric analysis such as CD5 and CD16, and to have an unclear borderline between the positive and negative cells. Therefore, even slight changes in the fluorescence intensity of these antigens could change the proportion of CD5+ CD19+, CD16+ CD57- and CD16+ CD57+ cells. However, these changes were not observed, when using the washed blood cells as samples after readdition of plasma to them. These data suggest that removal of plasma from blood before labelling the lymphocytes with fluorescein-conjugated antibodies is necessary to make the sample condition equal for flow cytometric analysis of lymphocyte subsets.

Adult↗
PubMed1991

[The changes in total and free catecholamine level in plasma in a patient with status asthmaticus].

Halothane was administered in oxygen to a young man in status asthmaticus whose bronchospasm did not respond to usual treatments. Plasma catecholamine concentrations were measured during and after bronchospasm. Fifteen minute inhalation of halothane produced marked bronchodilatation as reflected in decreased peak airway pressure, decreased wheezing and fall in PaCO2 from 110 mmHg to 45 mmHg. Treatment with halothane was discontinued after 120 min inhalation. Arterial blood samples were obtained to determine free and total catecholamine (CA) on the following four occasions: 1. during status asthmaticus, 2. fifteen minutes after inhalation of halothane, 3. one day after bronchospasm and 4. two days after bronchospasm. During attack, free norepinephrine and epinephrine concentrations were markedly elevated. These values decreased remarkably after administration of halothane. Total norepinephrine and epinephrine were also elevated during bronchoconstriction, and these high concentrations persisted after bronchodilatation. The changes in CA levels suggest that sympathoadrenal hyperactivity elicited by acute asthma can be suppressed by halothane as evidenced by the decreased concentration in free catecholamines, which are physiologically active. The levels in total catecholamine did not correlate with the patient's condition. Therefore, judgement based only on the levels in total CA might lead to misinterpretation in estimating sympathoadrenal activity.

Administration, Inhalation↗
PubMed1991

[Changes in plasma endothelin in patients undergoing cardiac valve replacement under high dose fentanyl anesthesia].

We measured plasma endothelin (ET) in 11 patients undergoing cardiac valve replacement under high dose fentanyl (116.6 +/- 15.4 micrograms.kg-1, mean +/- SD) anesthesia. Arterial blood samples were obtained: 1) before induction of anesthesia (control), 2) just before the start of cardiopulmonary bypass (CPB), and 3) just before the end of CPB. Endothelin levels were analyzed by radioimmunoassay based on double antibody method using Silica ODS suspension. ET concentrations in period 1, 2, and 3 were 3.0 +/- 1.1, 4.2 +/- 1.7 and 4.5 +/- 1.8 pg.ml-1 (mean +/- SD), respectively. There were no significant differences among these three values (P less than 0.05). The results suggest that under high dose fentanyl anesthesia, surgical stress including that of CPB might not affect ET concentration in plasma.

Aged↗
PubMed1991

Expression of terminal deoxynucleotidyltransferase gene in a case of adult T-cell leukemia.

A 37-year-old male from Kagoshima Prefecture was admitted with adult T-cell leukemia (ATL). Monoclonal integration of HTLV-1 proviral DNA was found, but the integration site was different from that of terminal deoxynucleotidyltransferase (TdT)-positive MT-1 cells (an ATL cell line). The ATL cells expressed enzymatically active TdT and exhibited 2100 b TdT mRNA, which corresponds to the thymus type of TdT mRNA. The same size of TdT mRNA was also detected in MT-1. Southern blot analyses revealed no differences in the gene structure of the promoter region of TdT genes between this ATL case and TdT-positive lymphoblastic leukemia cells. There is little possibility that cis-acting viral elements promote TdT gene expression by proviral integration. The activation of TdT gene in ATL may be mediated by other trans-acting factors.

Adult↗
PubMed1991

Translocation of hsp-70 and protein synthesis during continuous heating at mild temperatures in HeLa cells.

We have investigated intracellular translocation of hsp-70 and the synthesis of hsp-70 and total protein during heating at moderate temperatures in HeLa cells. When cells were heated at temperatures above 41 degrees C, hsp-70 translocated from the cytoplasm into the nuclei and apparently accumulated in nucleoli within 10 min. At temperatures above 42 degrees C, hsp-70 remained in the nuclei during heating. When cells were heated at 41 degrees C, the hsp-70 which had translocated into the nuclei returned gradually to the cytoplasm during heating. Synthesis of hsp-70 increased to three- to fourfold that in control cells, then decreased to the control level by 6-8 h. Total protein synthesis first decreased to 60% of the control level, then gradually recovered by 4 h. This indicates the acquisition of translational tolerance during heating at 41 degrees C. The return of hsp-70 to the cytoplasm is related to the recovery of total protein synthesis. Similar results were obtained at 42 degrees C heating in heat-induced thermotolerant cells. From these results, it is suggested that translocation of hsp-70 into the nuclei is very important for the recovery of protein synthesis (acquisition of translational tolerance) during heating at moderate temperatures. Also, cycloheximide and puromycin appeared to lower the temperature threshold about 1 degree C with respect to the translocation of hsp-70.

Cycloheximide↗
PubMed1990

[Experimental study relating to the anti-cancer effect of doxifluridine].

UNLABELLED: We investigated the anti-cancer effect of Doxifluridine (5'-deoxy-5-fluorouridine: 5'-DFUR) on an experimentally prepared tumor bearing mouse. METHOD: A 20-methylcholanthrene induced squamous cell cancer was prepared on the skin of ddN female mouse and 5'-DFUR was administered orally by catheter (90 mg/kg, 150 mg/kg, 210 mg/kg and physiological saline 0.5 ml/body). The each group consisted of 10 mice. Oral medications were performed once a day for one week (6 days continuous duration) and these medications were continued during a total period of four weeks. Once a week, the general condition of the animals was checked and at the same time, the size (length x width) of the tumor was measured, and the anti-cancer effect was determined. RESULT: It was noted between the control and 5'-DFUR medication group that there was a marked effectiveness on the rate of decrease in size and disappear of the squamous cell cancer according to the medication of 5'-DFUR. It regarded to the amount of 5'-DFUR, that there was a significant difference in the anti-cancer effect between 90 mg/kg and 210 mg/kg groups and between 150 mg/kg or 210 mg/kg and control groups. However, the difference could not be observed between 90 mg/kg and 150 mg/kg groups and between 150 mg/kg and 210 mg/kg groups.

Administration, Oral↗
PubMed1990

Immunohistochemical analysis of inflammatory infiltrates around the injection site of a streptococcal preparation, OK-432, in rat tongue.

On the assumption that neutrophils around the injection site of OK-432, a heat- and penicillin-treated lyophilized preparation of the Su strain of Streptococcus pyogenes, enhance immunologic response through the production of Interleukin-1 (IL-1), OK-432 was injected into rat tongue, and specimens from the tongue were immunohistochemically investigated at various intervals after the injection, to clarify the process of inflammatory and immune responses at the injection site. Neutrophils and mononuclear cells appeared around the OK-432 injection site after 1 hour, increased to their maximum level at 24 hours, and then decreased from the 3rd to the 7th day. IL-1 was detected on neutrophils 3 hours after the injection, and OX-08-positive cells (suppressor/cytotoxic T cells and the majority of natural killer cells) remarkably increased. OX-39-positive cells (IL-2 receptor) appeared after 12 hours. These results suggest that neutrophils around the injection site of OK-432 at early phases of inflammation play a role in the expression of BRM function through IL-1.

Acute-Phase Reaction↗
PubMed1990

Liver phosphatidylcholine hydroperoxidation provoked by ethionine-containing choline-deficient diet in mice.

It is shown that peroxidation of phosphatidylcholine (PC) is enhanced in liver of mice fed a hepatocarcinogenic choline-deficient diet containing 0.1% w/w ethionine. Mice were divided into 4 groups and fed for 4 weeks one of the following diets: choline-supplemented; choline-supplemented containing ethionine; choline-deficient; and choline-deficient containing ethionine. Phosphatidylcholine hydroperoxide (PCOOH) of liver lipids was measured by high performance liquid chromatography using a chemiluminescence detector. Mice fed a choline-deficient diet containing ethionine showed 6-fold higher PCOOH levels than the choline-supplemented control mice: the PCOOH/PC molar ratios of liver lipids were 32.3 X 10(-5) and 5.6 X 10(-5), respectively. In addition to this remarkable degree of lipid peroxidation in liver of mice fed the choline-deficient diet containing ethionine, we also observed a significant liver fatty infiltration, a decrease in plasma and liver alpha-tocopherol, and an increase in liver injury-indicative enzyme activities. Also, marker enzymes for hepatocarcinogenesis, glucose-6-phosphatase and gamma-glutamyl transpeptidase were affected. These data suggest that enhanced hydroperoxidation of phosphatidylcholine may participate in hepatocarcinogenesis provoked by choline deficiency in the presence of ethionine.

Animals↗
PubMed1990

Activity of dipeptidyl peptidase II and dipeptidyl peptidase IV in human gingiva with chronic marginal periodontitis.

The activity of DPP II was higher in gingiva from patients with periodontitis, but the activity of DPP IV, post-proline cleaving enzyme and collagenase-like peptidase was not significantly higher than that of the control group. As DPP II activity is known to be altered in immunological diseases, these findings may suggest some role for DPP II in the pathogenesis of chronic marginal periodontitis.

Adult↗
PubMed1990

Phospholipid hydroperoxide accumulation in liver of rats intoxicated with carbon tetrachloride and its inhibition by dietary alpha-tocopherol.

The formation and accumulation of phospholipid hydroperoxides, especially of phosphatidylcholine hydroperoxide (PCOOH), a primary peroxidation product of phosphatidylcholine (PC), in livers of carbon tetrachloride-intoxicated rats was investigated. PCOOH in liver and blood plasma was measured by a chemiluminescence-high-performance liquid chromatography procedure originally developed by Miyazawa et al. (Anal. Lett. 20, 915, 1987; Free Radical Biol. Med. 7, 209, 1989). Male Sprague-Dawley rats (120 g body wt., 5 weeks of age) were used in the experiments. The amount of PCOOH in the liver of control rats (CCl4-untreated) was 160 +/- 20 pmol/100 mg protein (mean +/- SD) and the PCOOH/PC molar ratio was 1.1 +/- 0.1 X 10(-5). In CCl4 (0.1 ml/100 g body wt.)-dosed rats, the liver PCOOH was 289 +/- 65 pmol/100 mg protein (PCOOH/PC = 2.4 +/- 0.4 X 10(-5], 764 +/- 271 pmol/100 mg protein (PCOOH/PC = 5.2 +/- 1.7 X 10(-5], and 856 +/- 165 pmol/100 mg protien (PCOOH/PC = 6.0 +/- 0.8 X 10(-5] at 6 h, 24 h, and 1 week after the dose, respectively. Under such conditions, the liver phosphatidylethanolamine hydroperoxide (PEOOH) level was not altered and the concentration was less than 100 pmol/100 mg protein even after the dose. The increments of liver PCOOH were suppressed 56% by the oral supplementation of DL-alpha-tocopherol (5 mg/100 g body wt./day) for a week before CCl4 administration. A relatively larger amount of PEOOH was found after stimulation of PC hydroperoxidation in the liver of rats with a large amount of CCl4 (0.25 ml/100 g body wt.) rather than with the small amount of CCl4 (0.1 ml/100 g body wt.).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Immunohistochemical analysis of effects of cyclosporin A on gingival epithelium.

Cyclosporin A (CSA)-induced gingival overgrowth was immunohistochemically compared with that phenytoin-induced and nonspecific inflammatory gingiva, and CSA concentration was determined for dental plaque. Leu-6+ epithelial dendric cells (EDC) were found to significantly decrease in number in CSA-induced gingival overgrowth, while the ratio of HLA-DR+ EDC to Leu-6+ EDC did not change significantly. The expression of class II major histocompatibility complex antigens, such as HLA-DR, -DP and -DQ on keratinocytes did not change by CSA-treatment. Leu-4+ mononuclear cells in CSA-induced gingival overgrowth were located primarily in the connective tissue far outside the epithelium. CSA concentration was much higher in dental plaque than in blood and other tissues. Immune response thus appears to be suppressed in the epithelial layer of CSA-induced gingival overgrowth through decrease in Leu-6+ HLA-DR+ EDC and T cell infiltration, both due to CSA in dental plaque. DNA polymerase alpha was detected in much fewer basal keratinocytes of CSA- and phenytoin-induced gingival overgrowth. Epithelial hyperplasia may thus be not due to increased keratinocyte proliferation, but rather to enhanced keratinocyte life span.

Adolescent↗