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Biomedical subjects

S Abe

Publications and source records attributed to S Abe.

At least 703 records · Page 39Linked to original sources

Novel phosphonoglycosphingolipids containing pyruvylated galactose from the nervous system of Aplysia kurodai.

We have reported the existence of a phosphonoglycosphingolipid containing a pyruvylated galactose, FGL-IIb, in nerve fibers of Aplysia kurodai (Araki, S., Abe, S., Ando, S., Kon, K., Fujiwara, N. & Satake, M. (1989) J. Biol. Chem. 264, 19922-19927). We have now isolated two other pyruvylated galactose-containing phosphonoglycosphingolipids, named FGL-V and FGL-IIa, from the nervous tissue of Aplysia, and characterized them as [3,4-O-(S-1-carboxyethylidene)]Gal beta 1----3GalNAc alpha 1----3[6'-O-(2- aminoethylphosphonyl)Gal alpha 1----2] (2-aminoethylphosphonyl----6) Gal beta 1----4Glc beta 1----1 ceramide and [3,4,O-(S-1-carboxyethylidene)] Gal beta 1----3GalNAc alpha 1----3[6'-O-(2-aminoethylphosphonyl)Gal alpha 1----2]Gal beta 1----4Glc beta 11----ceramide, respectively. Their major aliphatic components are palmitic acid, octadeca-4-sphingenine and anteisononadeca-4-sphingenine. Thus, the nervous system of Aplysia contains several pyruvylated phosphonoglycolipids.

Animals↗

Structure of triphosphonoglycosphingolipid containing N-acetylgalactosamine 6-O-2-aminoethylphosphonate in the nervous system of Aplysia kurodai.

A phosphonoglycosphingolipid, named F-21, was found in the nervous system of Aplysia kurodai by two-dimensional thin-layer chromatography (Abe, S., Araki, S., and Satake, M. (1986) Biomed. Res. (Tokyo) 7, 47-51). F-21 was isolated from the nervous tissue of Aplysia in this study, and its chemical structure was characterized as follows, where 2-AEP is 2-aminoethylphosphonate. (Formula; see text) The major aliphatic components of the ceramide portion were palmitic acid (75%), stearic acid (22%), octadeca-4-sphingenine (43%), and anteisononadeca-4-sphingenine (54%). Some information on the steric interactions in the sugar moiety was obtained by NMR spectroscopy. The ring protons of the internal galactose, H1, H3, and H4 and the H3 of the side chain galactose were shifted, as compared to the corresponding protons of dephosphonylated F-21. This may indicate the interactions between the 2-AEP residue of N-acetylgalactosamine and the internal galactose and between the N-acetyl group of N-acetylgalactosamine and the side chain galactose, implying a sterically restricted and unique structure that may relate to some biological functions of F-21.

Acetylgalactosamine↗

Purification and immunological characterization of a new form of gamma-glutamyltransferase of human semen.

A new form of gamma-glutamyltransferase was purified from human seminal plasma. The purified enzyme was composed of two non-identical subunits with apparent molecular masses of 150 and 95 kDa on polyacrylamide gel electrophoresis (PAGE) in the presence of sodium dodecyl sulfate (SDS), and showed a molecular mass of 500 and 250 kDa on gel filtration in the absence and presence of 1% Triton X-100, respectively. This enzyme was different from human renal gamma-glutamyltransferase not only in apparent molecular masses, but also in amino acid compositions of both the subunits to each other. Experiments with the antisera raised against the purified enzyme revealed that the enzyme was different from the renal, hepatic and testicular enzymes in reactivity to the antibody though partially related to those enzymes. Ouchterlony double diffusion analysis indicated that both human seminal plasma and prostatic extract contained two types of gamma-glutamyltransferase, one is that we purified and the other the renal type. Hence, it is most likely that gamma-glutamyltransferase accounting for most of the enzyme activity in semen results from prostata followed by secretion to seminal plasma.

Amino Acids↗

Induction of morphological change by tyrosine kinase inhibitors in Rous sarcoma virus-transformed rat kidney cells.

Erbstatin and methyl 2,5-dihydroxycinnamate, related tyrosine kinase inhibitors, induced a morphological change in temperature-sensitive Rous sarcoma virus-transformed rat kidney (RSVts-NRK) that brought the cells close to the morphology of their normal counterpart. Erbstatin did not change the morphology of normal or Kirsten sarcoma virus-transformed rat kidney cells. Erbstatin also inhibited morphological transformation of RSVts-NRK cells induced by a shifting in temperature. Actin stress fibres were observed only in normal cells and not in transformed cells. Erbstatin induced stress fibre organization in transformed cells. Erbstatin and methyl 2,5-dihydroxycinnamate increased fibronectin gene expression in RSV-transformed cells. Thus, tyrosine kinase inhibitors induced normal phenotypes specifically in v-src-expressing cells.

Actins↗

Transgenic mice susceptible to poliovirus.

Poliovirus-sensitive transgenic mice were produced by introducing the human gene encoding cellular receptors for poliovirus into the mouse genome. Expression of the receptor mRNAs in tissues of the transgenic mice was analyzed by using RNA blot hybridization and the polymerase chain reaction. The human gene is expressed in many tissues of the transgenic mice just as in tissues of humans. The transgenic mice are susceptible to all three poliovirus serotypes, and the mice inoculated with poliovirus show clinical symptoms similar to those observed in humans and monkeys. Rabbit antipoliovirus serum detects the antigens mainly in motor neurons in the anterior horn of the spinal cord and in nerve cells in the medulla oblongata and pons of the paralyzed transgenic mice. Therefore, cell types sensitive to poliovirus in the central nervous system of the transgenic mice appear to be identical to those of humans and monkeys. Furthermore, many more doses of oral poliovirus vaccine strains than of the virulent strains are required to cause paralysis in the transgenic mice. This may reflect the observation that the virulent strain multiplies more efficiently in the central nervous system than the attenuated strain. Thus, the transgenic mice may become an excellent new animal model to study molecular mechanisms of pathogenesis of poliovirus and to assess oral poliovirus vaccines.

Animals↗

Nucleolar organizer regions in precancerous and cancerous lesions of the bronchus.

Using a silver staining technique, nucleolar organizer region-associated proteins (Ag-NOR) were studied in paraffin sections of five specimens of normal bronchial epithelium, eight of atypical squamous metaplasia, five of carcinoma in situ, and seven of microinvasive squamous cell carcinoma. The mean number of Ag-NOR in the nucleus were normal epithelium 1.2 +/- 0.1 (mean +/- SD), atypical squamous metaplasia (borderline lesion) 2.2 +/- 0.5, carcinoma in situ 3.8 +/- 0.6, and microinvasive squamous cell carcinoma 4.8 +/- 1.1. There was a highly significant difference between the Ag-NOR numbers in the atypical squamous metaplasia and those in the carcinoma in situ (P less than 0.01). The Ag-NOR staining is a useful technique for the differential diagnosis of difficult borderline lesions in the bronchial epithelium.

Bronchial Neoplasms↗

Picture archiving and communication system in Hokkaido University Hospital: advantage and disadvantage of HU-PACS chest roentgenogram images in the outpatient clinic.

A new Hokkaido University picture archiving and communication system (HU-PACS) has been in clinical use in the outpatient clinic at HU Hospital. To evaluate the quality of the cathode-ray tube (CRT) monitor images, we compared the detectability of line shadows in the chest roentgenogram images on the CRT monitor with those on the computed radiography (CR) film. We randomized chest roentgenograms from 20 patients who were admitted to the outpatient clinic with pulmonary disease. Two physicians, whose speciality is chest roentgenogram diagnosis, checked whether they could recognize a horizontal fissure line (hairline) on the posteroanterior view and a minor fissure line and major fissure lines on the lateral view. Only 30% of hairlines were recognized on CRT monitor as compared with 65% on CR film. On the lateral view, only 68% of major fissures and 53% of minor fissures on CRT monitor were recognized as compared with 89% and 79%, respective on CR film. Furthermore, it was somewhat difficult to follow entire lines on some of the CRT monitor images. Clinically, the greatest advantage of the PACS is immediate availability of images, including chest roentgenogram, chest computed tomography (CT) and magnetic resonance imaging (MRI). PACS is also convenient for consulting colleagues in other departments. Unfortunately, the quality of the image on the CRT monitor is not yet good enough to visualize line shadows and small solitary lesions on the chest roentgenogram image. Recent advances in high technology have been so rapid, however, that higher resolution CRT monitors will be available soon.

Computer Terminals↗

Management and clinical utilization of computed tomography, magnetic resonance imaging, and angiography in Hokkaido University Hospital picture archiving and communication system.

We made a preliminary assessment of the Hokkaido University picture archiving and communication system (HU-PACS). Data access time from either imaging machines or data base to workstations was 1.5 minutes, which is great benefit for data communication in routine examinations. Image quality of the work station was estimated in terms of brain computed tomography (CT) and digitized cerebral angiograms. Cerebral infarction was definitely observed on the cathode-ray tube (CRT) monitor of the work station. Although the picture quality of CRT was acceptable, we had to manipulate window level and width for CRT diagnosis of cerebral angiography. Data compression was routinely used without significant degradation of those image quality. Nevertheless, further improvement of maneuverability of the workstation should be considered.

Angiography, Digital Subtraction↗

Functional recovery of hibernating myocardium after coronary bypass surgery: does it coincide with improvement in perfusion?

To determine the relationship between functional recovery and improvement in perfusion after coronary artery bypass graft surgery (CABG), 49 patients were studied. Radionuclide angiography was performed before, 1 month after, and 6 to 12 months after CABG to evaluate regional wall motion. Exercise thallium-201 myocardial perfusion imaging was done before and 1 month after CABG to assess regional perfusion. Preoperative asynergy was observed in 108 segments, and 74 of them showed an improvement in wall motion 1 month after CABG (segment A). Sixty-six of these segments (89%) were associated with an improvement in perfusion. Eight segments that had not improved 1 month after CABG demonstrated a delayed recovery of wall motion 6 to 12 months after CABG (segment B). However, seven of eight segments (88%) already showed an improvement in perfusion 1 month after CABG. A total of 82 segments exhibited functional recovery after CABG and were considered hibernating segments. In the preoperative study segment B more frequently had areas of akinesis or dyskinesis than segment A (75% vs 34%, p less than 0.05). The mean percent thallium-201 uptake in segment B was lower than that in segment A (74% +/- 9% vs 83% +/- 8%, p less than 0.05). Functional recovery of hibernating myocardium usually coincided with an improvement in perfusion. However, delayed functional recovery after reperfusion was observed in some instances. Severe asynergy and severe thallium-201 defects were more frequently observed in these segments with delayed recovery. Hibernating myocardium might remain stunned during those recovery periods.

Coronary Artery Bypass↗

Determination of plasma leukotrienes in antigen-induced bronchoconstrictive guinea pigs.

Convenient extraction and radioimmunoassay methods for measurement of leukotrienes C4 and D4 (LTC4 and LTD4) in biological fluids are described. LTC4 or LTD4 in plasma was extracted with acetonitrile, and the extract was washed with dichloromethane then adjusted to pH 3.5 or 6.0, respectively. Each leukotriene was partially purified by using a C18-bonded silica cartridge and quantitated by radioimmunoassay. Amounts of LTC4 and LTD4 in the range of 0.025-1.6 ng could be assayed in plasma. This procedure was employed to examine the increase in plasma LTC4 (0.249 +/- 0.036 ng/ml) and LTD4 (1.399 +/- 0.235 ng/ml) of guinea pigs during intravenous challenge-induced anaphylactic bronchoconstriction, and the suppression of the increase of bronchoconstriction and leukotrienes by the administration of 5-lipoxygenase inhibitors such as E6080 (6-hydroxy-2-(4-sulfamoylbenzyl-amino)- 4,5,7-trimethylbenzothiazole hydrochloride), AA861 (2,3,5-trimethyl-6-(12-hydroxy-5,10-dodecadiynyl)-1,4-benzoquinone ) and phenidone. On the other hand, LTC4 and LTD4 were not detected in plasma after an inhaled challenge, though significant bronchoconstriction was provoked. It was concluded that the present study validates a new technique for quantitating plasma leukotrienes on the basis of pH and a suitable method for evaluating the pharmacological efficacy of 5-lipoxygenase inhibitors.

Administration, Inhalation↗

Evidence for the existence of cytoskeleton-bound polysomes in plants.

When conventional, high ionic strength buffers were used for the isolation of polysomes from pea plants, less than 20% were retained in the detergent-insoluble pellet. Reducing Tris, K+ and Mg++ to 10 mM increased retention to 70%, and when a new, microfilament-stabilizing buffer was used, retention increased to 80%. Conditions which favoured polysome pelleting at lower g forces permitted the retention of actin in the pellet. The data are consistent with the hypothesis that higher plants, like animals, contain cytoskeleton-(actin)-bound polysomes.

Cytoskeleton↗

Effect of a novel 5-lipoxygenase inhibitor, E6080 on bronchospasm, airway cellular infiltration and leukotriene production in guinea pigs.

6-Hydroxy-2-(4-sulfamoylbenzylamino)-4,5,7-trimethylbenzothiazo le hydrochloride (E6080), an orally active and selective 5-lipoxygenase inhibitor, dose-dependently inhibited the bronchospasm induced by antigen (ovalbumin) inhalation in sensitized conscious guinea pigs. The inhibitory effect of E6080 was more potent than that of a typical 5-lipoxygenase inhibitor, AA861, but less than that of a leukotriene (LT) antagonist, LY171883. When airway infiltration of neutrophils and eosinophils was measured in bronchoalveolar lavage fluid (BALF) at 6 h after antigen inhalation by passively sensitized guinea pigs, the inhibitory effect of E6080 on neutrophil infiltration was more marked than that on eosinophil infiltration. The inhibitory effect of E6080 on bronchoalveolar cellular infiltration and bronchoepithelial damage was confirmed by examination of photomicrographs of the lung. In addition to the above pharmacological effects, E6080 inhibited the increase in BALF levels of both i-LTC4 and i-LTB4. These results suggest that E6080 may prove to be effective for the treatment of asthma, in which large amounts of leukotrienes (LTs) are elaborated.

Acetophenones↗

An overview of pregnancy in women with underlying renal disease.

This is a report of a retrospective study of the effects of preexisting glomerular disease and pregnancy on each other. Two hundred forty pregnancies in 166 Japanese women who delivered between 1970 and 1988 were analyzed. There were 206 (86%) live births, 14 (6%) perinatal deaths, and 20 (8%) spontaneous abortions. Perinatal loss was greatest in women with hypertension and/or glomerular filtration rate (GFR) less than 70 mL/min before conception. Pregnancy did not appear to adversely affect the underlying glomerular disease if GFR was greater than 70 mL/min and blood pressure was below 140/90 mm Hg. However, with moderately impaired renal function (creatinine greater than 124 mumol/L [1.4 mg/dL] or GFR less than 50 mL/min), the long-term prognosis was poorer, despite generally favorable obstetrical outcomes. Gravidas with membranoproliferative glomerulonephritis had the highest rates of hypertension (29%) and decreased renal function (33%) at final follow-up, ie, the type and severity of glomerulonephritis had a major impact on clinical course.

Female↗

Pregnancy in IgA nephropathy.

The impacts of IgA nephropathy and pregnancy on each other were evaluated in 118 women who conceived 168 times between 1970 and 1988. Rates of spontaneous abortion, normal delivery, live birth and perinatal death were 9, 66, 87 and 4%, respectively. Infants born to women with glomerular filtration rates (GFR) lower than 70 ml/min prior to conception had a higher perinatal mortality rate (14% vs. 3%, P less than 0.001). This was also true if pre-pregnancy blood pressures were consistently higher than 140/90 mm Hg (33% vs. 1%, P less than 0.001). These were the figures for the whole 18 year period, but stratification of the data revealed that most adverse results occurred in the 1970's, during which the perinatal death rate was 9%, while it was 0% in the 1980's. Eighty-five women were followed for three years or more. At final follow-up, the rates of decrease in GFR, and increases in blood pressure and proteinuria were 19, 11 and 7%, respectively. In most patients the natural history of IgA nephropathy was similar to that of women who had not experienced pregnancy, but there were five instances where gestation seemed to accelerate functional loss, with rapid development of end-stage or near end-stage renal failure. Most women with IgA nephropathy should anticipate few problems with pregnancy, if they are normotensive and their preconception GFR exceeds 70 ml/min. The gestation in such instances should have little influence on the natural history of their nephropathy.

Blood Pressure↗

Investigation of the active site of Bacillus macerans cyclodextrin glucanotransferase by use of modified maltooligosaccharides.

The active site of Bacillus macerans cyclodextrin glucanotransferase (CGTase) was examined by use of derivatives of phenyl alpha-maltopentaoside and phenyl alpha-glucoside as the substrates and acceptors, respectively. The active site of this enzyme is considered to be composed of tandem subsites (S4, S3, S2, S1, S1', S2', etc.) geometrically complementary to several glucose residues, and the alpha-1,4-glycosidic linkage of a substrate is split between S1 and S1'. The features of subsites S3 and S4 of the glycon binding site were estimated from the modes of the enzymatic action on phenyl alpha-maltopentaoside (G-G-G-G-G-phi; G, glucose residue; phi, phenyl residue; -, alpha-1,4-glycosidic bond) and its derivatives in which the CH2OH groups of the non-reducing-end glucose residues were converted to CH2I (IG-G-G-G-G-phi; IG, 6-deoxy-6-iodo-D-glucose residue), CH2NH2 (AG-G-G-G-G-phi; AG, 6-amino-6-deoxy-D-glucose residue), or COOH (CG-G-G-G-G-phi; CG, glucuronic acid residue). p-Nitrophenyl alpha-glucopyranoside (G-P; P, p-nitrophenyl residue) was used as an acceptor. HPLC analysis of the digests revealed that the CG residue of CG-G-G-G-G-phi was excluded from subsite S3, while it was accommodated in subsite S4. The Km and Vmax values for CG-G-G-G-G-phi were remarkably larger and smaller, respectively, than those for any other substrates.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacillus↗

Macular choroidal occlusion in dysplasminogenemia.

The authors describe a family with dysplasminogenemia. This diagnosis was based on a lowered ratio of functional plasminogen activity to immunologic plasminogen antigen level, associated with fundus abnormalities. The proband is a 31-year-old woman with Graves disease who had choroidal occlusive lesions of the macula in both eyes. The results of the laboratory examination indicated that the patient was a homozygote for dysplasminogenemia. Similar examinations of the patient's parents and siblings showed their plasminogen levels to be 50% below normal. The thrombotic tendency in this disorder appeared to be responsible for the pathogenesis of the macular choroidal occlusion.

Adult↗

Repeated intestinal ulcerations in a patient with systemic lupus erythematosus and high serum antiphospholipid antibody levels.

We report the case of a patient with SLE who had repeated ulceration of the small intestine requiring emergency surgery. Pathologic examination revealed microthrombosis and vasculitis at the site of the intestinal ulcers. High levels of antiphospholipid antibodies, thrombocytopenia, and prolonged prothrombin time coincided with the episodes of intestinal ulceration. Antiphospholipid antibodies may be involved in the development of thrombosis resulting in the repeated episodes of intestinal ulceration in this patient. This possibility should be considered in patients with SLE who have intestinal ulceration and appropriate antithrombotic medication should be administered.

Adult↗