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N Shindo

Publications and source records attributed to N Shindo.

At least 55 records · Page 3Linked to original sources
PubMed1988

Rapid quantification of 11 prostanoids by combined capillary column gas chromatography and negative ion chemical ionization mass spectrometry: application to prostanoids released from normal human embryonic lung fibroblasts WI38 in a culture medium.

The rapid and simultaneous quantification of 11 prostanoids has been carried out with a short-capillary gas chromatograph and negative ion chemical ionization (ammonia) mass spectrometer. The methoxime-trimethylsilyl ether-pentafluorobenzyl esters (MO-TMS-PFB) of nine prostanoids, PGA1, PGA2, PGB1, PGB2, PGD2, PGE1, PGE2, 6-oxo-PGF1 alpha and TXB2 and the TMS-PFB of two prostanoids, PGF1 alpha and PGF2 alpha, were separated in less than 5.5 min on a bonded OV-1 capillary column 0.25 mm i.d. x 6 m (0.15 micron thickness) using hydrogen as a carrier gas. PGD2, PGE2, PGF2 alpha, 6-oxo-PGF1 alpha and TXB2 were quantified up to 2.5 fmol injected (0.1 pmol derivatized) and both PGA2 and PGB2 up to 25 fmol injected (1 pmol derivatized). In order to maintain the stability of the prostanoids containing a carbonyl group, such as TXB2 during the purification and derivatization steps of biological materials, methyl acetate was used in place of methyl formate as an eluant for Sep-Pak C18 purification. Normal human embryonic lung fibroblasts W138 (5.63 x 10(5) cells in a log phase) produced: PGA2 15.28, PGB2 13.48, PGD2 7.95, PGE1 2.62, PGE2 177.76, PGF2 alpha 25.14, 6-oxo-PGF1 alpha 27.33 and TXB2 61.00 pmol in 10 ml of Eagle minimal essential medium.

Calibration↗
PubMed1987

Nephritogenic glycoprotein. XII. Focal glomerulonephritis with myeloid bodies produced in rats by synthetic analogues of the glycopeptide, nephritogenoside.

Glomerular lesions were successfully induced in rats by a single footpad injection of synthetic analogues of nephritogenoside [alpha-Glc-(1----6)-alpha-Glc-(1-NHCO-Asn, and -Gln)]. Characteristic morphological changes of these glomerular lesions are (1) focal glomerulonephritis (FGN) and (2) the appearance of myeloid bodies in the epithelial cells of the podocytes. FGN produced by a single injection of the synthetic analogues of nephritogenoside may provide an experimental animal model of this potentially diffuse disease, since morphological changes in the early stage of sclerosing glomerulonephritis (end-stage kidney) induced by a single footpad injection of natural nephritogenoside are often identical to those of FGN.

Animals↗
PubMed1986

Biochemical mechanisms of aminoglycoside cell toxicity. I. The uptake of gentamicin by cultured skin fibroblasts and the alteration of lysosomal enzyme activities.

In order to study the toxicity of aminoglycoside, human skin fibroblasts were used as a model for basic studies, since they are known to have a specific aminoglycoside-binding site and to translocate the drug into the cells. Following the exposure of fibroblasts to gentamicin for 3 days, the cells formed many osmiophilic lamellar materials (myeloid bodies) in the lysosomes, while the other cellular structures appeared to remain normal. Although gentamicin was intensively accumulated within the lysosomes, intralysosomal pH, determined by the fluorescence intensity ratio method using fluorescein-isothiocyanate-labeled dextran, did not alter. Among the lysosomal enzymes, the activities of six different glycosidases were unchanged. On the other hand, sphingomyelinase and acid lipase activities were greatly decreased, while phospholipase A activity was increased. These results indicate that the lipid metabolism of fibroblasts is altered by gentamicin treatment, and that perturbation of intralysosomal pH can not be the cause of the changes observed in cell lysosomal enzyme activities.

Cells, Cultured↗
PubMed1984

Immunoelectron microscopic (IEM) studies on glutaraldehyde-fixed renal specimen.

Immunofluorescent microscopy (IF) has become an essential tool in the routine diagnosis of renal pathology. It is thought that glomerular IF patterns represent different forms of immunologically mediated glomerular lesions. However, in order to preserve antigenicity IF is usually done on frozen, unfixed specimen by light microscopy and it is difficult to locate target macromolecules in tissue with precision. In order to establish the precise location of such macromolecules in glomeruli in relation to the ultrastructure, we undertook an immunoelectron microscopic (IEM) study on renal biopsies. Percutaneously biopsied tiny specimen was fixed in glutaraldehyde and processed with protease. Using peroxidase-labeled antisera, a direct IEM was done. With this technique, target macromolecules corresponded well not only to electron-dense deposits but also to IF patterns. In one case of membranous nephropathy, immunoglobulin (Ig) was found to be outside of the glomerular basement membrane (GBM), while IgA was seen to be inside the GBM. For this same case, a similar localization of immunoglobulins was not revealed by IF. In conclusion, IEM is a useful technique that can broaden our knowledge of pathogenic mechanisms in glomerular disease.

Adult↗
PubMed1981

Determination of glutamic acid and gamma-aminobutyric acid in Ringer's solution without desalination at the femtomole level by gas chromatography chemical ionization mass spectrometry.

For the quantification of glutamic acid in Ringer's solution, pentafluoropropionic methyl ester was the most sensitive derivative. The detectable concentration was 0.01 microM glutamic acid in Ringer's solution; the amount of the preparation was 1 pmol and the injection into a gas chromatograph mass spectrometer was 10 fmol. For the quantification of gamma-aminobutyric acid in Ringer's solution, the trifluoroacetal-hexafluoropropionyl ester was quantification of gamma-aminobutyric acid in Ringer's solution, the trifluoroacetal-hexafluoropropionyl ester was detectable at a concentration of 0.01 microM. Ringer's salts facilitated acylation in the order heptafluorobutyric anhydride greater than pentafluoropropionic anhydride greater than trifluoroacetic anhydride. The effect depended on esterification of carboxy groups in the order methyl ester greater than hexafluoropropionyl ester greater than butyl ester. Sodium carbonate, sodium acetate and sodium citrate also facilitated acylation with pentafluoroproionic anhydride, while sodium phosphate inhibited the acylation and sodium sulfate inhibited it slightly. The pentafluoropropionic methyl ester of glutamic acid was stable for up to 10 days, when it was dissolved in acetone and stored at -18 degrees C.

Gas Chromatography-Mass Spectrometry↗
PubMed1980

[Studies on the stability of aclacinomycin hydrochloride. I. Stability of solution of aclacinomycin hydrochloride (author's transl)].

Aclacinomycin is an antitumor anthracycline antibiotic isolated from the culture broth of Streptomyces galilaeus MA144-M1. In this study, the effects of heat, light and pH on the aqueous solution of aclacinomycin hydrochloride (ACM-HCl) were investigated. The following results were found: (1) The kinetic studies revealed that the thermal inactivation of ACM-HCl solution (pH 4.5) was based on the apparent first-order reaction and that Arrhenius equation was confirmed to be established between the rate constants and temperatures. When ACM-HCl solution was stored at 20, 10 and 5 degrees C, the estimated term of ACM-HCl solution at the time when the initial activity (100%) reduced to 90% residual concentration was 1.5, 6 and 12 months, respectively. (2) It was clarified by pH-log k profile that ACM-HCl solution was most stable near at pH 4.5. (3) The higher the buffer concentration was used, the faster the degradation rate, but there was no difference between the residual activity ratios at the various concentrations of ACM-HCl solution. (4) The inactivation of ACM-HCl solution under sunlight occurred in a type of zero-order reaction so that the faster inactivation rates were obtained at the more diluted concentration of ACM-HCl. (5) The major degradation products of ACM-HCl solution were 1-deoxypyrromycin (DP), MA144 S1 (S1) and bisanhydroaklavinone (F1). DP and S1 were mainly found at pH below 4.0 and F1 at pH above 5.0. The degradation under sunlight gave L1 (N-monodemethyl ACM) accompanied by the degradation of aglycone moiety in part.

Aclarubicin↗
PubMed1977

Recommended method for the analysis of amino acids in biological materials.

Fifty-five ninhydrin-positive compounds in physiological fluids were determined with a Hitachi Model KLA-5 amino acid analyzer by a two-column chromatographic procedure. Both columns were packed with Hitachi Custom 2618 ion-exchange resin. The total analysis time was 9.5 h. In this procedure, particularly glucosamine, mannosamine and galactosamine were separated completely from normal "protein" amino acids, and NG-monomethylarginine, NG, NG-dimethylarginine and NG,NG-dimethylarginine, which were present in the myelin basic protein of several species and excreted in human urine, were separated from other basic amino acids. The method is useful for various applications with biological materials.

Amino Acids↗