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Biomedical subjects

K Kamio

Publications and source records attributed to K Kamio.

28 records · Page 2Linked to original sources
PubMed1992

[Characterization of glycolipid sulfotransferase fractionated from rat kidney and involvement of the enzyme in human cancer].

3'-Phosphoadenosine 5'-phosphosulphate: galactosylceramide sulfotransferase which catalyzes the sulfation of galactosylceramide (GalCer) was partially purified from a rat kidney light membrane fraction, and the properties were studied with special reference to substrate specificity. In order to study minimum molecular requirement of the acceptor substrate for the sulfotransferase, analogues of galactosylceramide where omega-amiocaproic or omega-aminododecanoic acid is substituted for the acyl moiety of the native glycolipid were chemically synthesized by improved procedures. The artificial glycolipids were sulfated effectively by the kidney enzyme, suggesting that the synthetic compounds will serve for affinity ligands for the purification of the enzyme. The extent of sulfation in the synthetic compounds was comparable with that of galactosylceramide containing normal acids and higher than that of galactosylsphingonine in which one of hydrocarbon chains is deleted from the native glycolipid. Through substrate specificity experiments, the sulfotransferase has relatively broad specificity acting on beta-linked galactosides at nonreducing ends of mono- and disaccharides which bind, at least, one hydrocarbon chain. Enzyme kinetic analysis by competition assay using mixed acceptors demonstrated that the same, single sulfotransferase catalyzes sulfation of galactosylceramide, lactosylceramide and galactosylsphingosine. As to human cancer, the sulfotransferase activity was hardly detectable in Wilms' tumor tissues that contrasts with renal cell carcinoma tissues where the markedly elevated level was previously demonstrated. When sera from patients with various cancers were examined for the enzyme level, many cases of hepatocellular carcinoma showed significantly increased activity, whereas the hepatoma tissues had hardly detectable level of the enzyme. These observations suggest that a humoral factor derived from the hepatoma induces the sulfotransferase.

Animals↗
PubMed1992

[Neuromyopathy induced by halothane anesthesia and muscle relaxants for status asthmaticus--report of 2 patients].

Two patients with status asthmaticus (a 30-year-old female and a 48-year-old male) who developed flaccid quadriplegia and sensory impairment of glove and stocking type after treatment with halothane, muscle relaxants (pancuronium and vecuronium) and steroid are described. They noted motor and sensory impairment immediately after recovery from control ventilation for treatment of status asthmaticus. Histochemical examinations of biopsied muscle demonstrated the necrosis and regeneration of muscle fibers and small diameters in type I fibers. These results suggested that the involvement of muscle (myopathy) was a consequence of the harmful action of halothane and muscle relaxants together with steroids on muscle fibers with subclinical fragility. The sensory impairment (neuropathy) was considered to have been produced mainly by the halothane together with muscle relaxants and aminoglycosides.

Adult↗
PubMed1992

Improved preparation method for lysogangliosides.

Lyso-GM3 and -GM1 gangliosides were prepared from the corresponding N,N'-dideacylated gangliosides using N-trifluoroacetylation at the sphingosine moiety, followed by N-acetylation and mild saponification. The blocking reaction was performed using a water-ether bilayer system at alkaline medium, in which the N-trifluoroacetylation occurred predominantly at the lipid moiety. Through the procedure, lysoGM3 and lysoGM1 were obtained with higher yields from the corresponding dideacylated gangliosides than through the previous method using 9-fluorenylmethoxycarbonyl chloride as a blocking group or of direct N-acetylation of it on liposomes containing starting ganglioside and other lipid. Chemical structures of the lysogangliosides and the synthetic intermediates were confirmed by the proton nuclear magnetic resonance spectrometry and negative fast atom bombardment-mass spectrometry.

Acetates↗
PubMed1992

Galactosylceramide containing omega-amino-fatty acids: preparation, characterization, and sulfotransferase acceptor.

For preparation of an affinity ligand, an N-fatty acyl moiety of galactosylceramide (GalCer) was chemically replaced with omega-amino-fatty acid including amino-n-hexanoic acid or amino-n-dodecanoic acid to obtain omega-aminoGalCer. For the synthesis of the compound, galactosylsphingosine (GalSph) was coupled with N-trifluoroacetyl omega-amino-fatty acid which was prepared by a reaction with S-ethyltrifluorothioacetate. After removal of the N-trifluoroacetyl group in a mild alkaline solution, in which an N-fatty acyl group was retained, aminoGalCer composed of an N-hexanoyl or an N-dodecanoyl group was obtained with an overall yield of 90%. Their chemical structures were confirmed by proton nuclear magnetic resonance and fast atom bombardment-mass spectrometries. These aminoGalCers and GalSph as well as immobilized aminoGalCer were sulfated by a glycolipid sulfotransferase from rat kidney. Furthermore, immobilized aminoGalCer on gel matrix was used for affinity chromatography of the sulfotransferase, resulting in an excellent increase in the purification (14,000-fold) with a recovery rate of 40%.

Aminocaproic Acid↗
PubMed1991

Elevated serum level of glycolipid sulfotransferase in patients with hepatocellular carcinoma.

Activity of glycolipid sulfotransferase (cerebroside sulfotransferase) in serum was elevated in 21 (33%) of 63 patients with hepatocellular carcinoma (HCC, mean +/- S.E., 349 +/- 32 pmol/ml per h, n = 63, P less than 0.001) compared to healthy subjects (172 +/- 12, n = 85). Ho significant elevation of the sulfotransferase level was observed in liver cirrhosis (219 +/- 28, n = 10) in which many of biochemical HCC markers increase concomitantly. The elevation of sulfotransferase was independent of the production of alpha-fetoprotein and of aminotransferase levels in HCC, providing complementary value for alpha-fetoprotein-negative HCC cases. However, the sulfotransferase levels (234 +/- 21, n = 32, P less than 0.01) in sera from patients with renal cell carcinoma, in whose involved tissues the enzyme was demonstrated to increase markedly, were less than in HCC.

Carcinoma, Hepatocellular↗
PubMed1991

Distinctive glycolipid patterns in Wilms' tumor and renal cell carcinoma.

Glycolipid patterns were analysed chromatographically in Wilms' tumor and renal cell carcinoma tissues and compared with those of uninvolved tissue. Ganglioside GM3 was found to be increased in both cancer tissues, whereas sulfatides accumulated only in renal cell carcinoma, as reported earlier. Neolactotetraosylceramide was detected in both cancer tissues, but not in the uninvolved kidney tissues. In four cases of Wilms' tumors, only a low level of sulfotransferase towards galactosylceramide was found in one case, while no activity was detected in the three other cases. Present results show that the increased sulfatide(s) in the renal cell carcinoma and the deficiency of the sulfatides in Wilms' tumors appear to be biochemical characteristics of histologically different carcinomas.

Carcinoma, Renal Cell↗
PubMed1990

Tenotomy and postoperative brace treatment for muscular torticollis.

A postoperative corrective brace for congenital muscular torticollis is introduced and the results and indications for its use are presented. Thirty-three of 55 patients who underwent open tenotomy of the sternocleidomastoid muscle with application of the brace following surgery were evaluated in follow-up. Tenotomy was performed at the sternoclavicular origin of the muscle. The mean age at operation was six years; the mean follow-up period was seven years. The results were good in 21 patients (64%), fair in seven (21%), and poor in five (15%). Facial asymmetry remained in all patients over the age of ten who underwent operation. Alopecia, one of the complications of the brace, was found only in patients under age five. This combined treatment with tenotomy and postoperative brace is considered best indicated for patients between six and ten years of age.

Adolescent↗
PubMed1989

Association of elevated sulfatides and sulfotransferase activities with human renal cell carcinoma.

Lactosylceramide sulfate and galactosylceramide sulfate were found to increase markedly in human renal cell carcinoma (adenocarcinoma) as compared to uninvolved tissue. Activities of two sulfotransferases toward galactosylceramide and lactosylceramide as substrates were significantly elevated in the carcinoma compared to the uninvolved tissue resulting in enhanced synthesis of the two sulfatides in the carcinoma. The elevation of the two sulfotransferases was parallel in most tumors, suggesting that the same enzyme is responsible for the enhanced synthesis of two sulfatides. No consistent difference in the activity of arylsulfatase A, which desulfates the two sulfatides, was observed between the carcinoma and uninvolved tissue. Both the present and previous results show that the increased synthesis of the sulfatide(s) due to elevated sulfotransferase activity could be a biochemical characteristic common to adenocarcinomas derived from different tissues.

Adenocarcinoma↗