The occurrence of polysialogangliosides including ganglio-N-tetraose series in adult bovine nasal cartilage

We extracted glycolipids from adult bovine nasal cartilage and purified some glycolipids by DEAE-Sephadex A-25 and Iatrobeads column chromatography. Cartilage contained 20 nmol of lipid bound sialic acid per gram wet tissue. The relative content of mono, di, tri, and tetrasialo gangliosides were 14%, 40%, 28% and 18%, respectively, as sialic acid content. We characterized some by examining carbohydrate composition, methylation analysis, sialidase treatment and mild acid hydrolysis. The ganglio-N-tetraose series, including GDla, GDlb, GTla, GTlb and GQlb, was identified as one of the major ganglioside groups of this cartilage.     

Effects of combinations of transforming growth factor-beta 1 and tumor necrosis factor on induction of differentiation of human myelogenous leukemic cell lines

Effects of transforming growth factor-beta 1 (TGF-beta 1), either alone or in combination with TNF, on the induction of differentiation of human myelogenous leukemic cell lines were examined. TGF-beta 1 alone induced differentiation of a human monocytic leukemia U-937 line into the cells with macrophage characteristics. When combined with TNF, TGF-beta 1 synergistically or additively induced differentiation associated properties. A human myeloblastic leukemia cell line, ML-1, differently responded to TGF-beta 1 in induction of differentiation. FcR activity and phagocytic activity induced by TNF were suppressed by TGF-beta 1. However, nitroblue tetrazolium reducing activity was synergistically induced by combinations of TGF-beta 1 and TNF. Scatchard analysis of TNF receptors indicated that the number of binding sites and dissociation constant of TNF for its receptors on U-937 or ML-1 cells were not changed by treatment with TGF-beta 1. Although IFN-gamma, IL-6, granulocyte CSF, and granulocyte-macrophage CSF-induced nitroblue tetrazolium reducing activity of U-937 cells, only IFN-gamma, and TNF induced it synergistically in combination with TGF-beta 1. Synergism between TGF-beta 1 and TNF was also observed in inhibition of growth of U-937 and ML-1 cells. Although TGF-beta 1 induction of differentiation of other monocytoid leukemic THP-1 cells was similar to that of U-937 cells, TGF-beta 1 only slightly induced differentiation of promyelocytic leukemic HL-60 cells, either alone or in combination with TNF. Our observations indicate that TGF-beta 1 strongly modulates differentiation and proliferation of human myelogenous leukemia cells, macrophage precursors.     

Enzymatic removal of bilirubin toxicity by bilirubin oxidase in vitro and excretion of degradation products in vivo

The toxic effects of the degradation products of bilirubin that were formed by reaction with bilirubin oxidase were investigated with the C 1300 mouse neuroblastoma cell line by examining the following parameters: growth inhibition, morphologic characteristics, membrane transport, DNA synthesis, and protein synthesis. The addition of bilirubin to the cells resulted in definite cytotoxic effects on all of these parameters in a dose-dependent fashion; the addition of bilirubin oxidase reversed the toxic effects on the C 1300 cells in vitro. Furthermore, we found that most of these enzymatic degradation products of bilirubin were excreted by the kidney into the urine in a few hours after intravenous injection of the degradation products; in contrast, no intact bilirubin was excreted. Thus, these findings suggest that hyperbilirubinemia in newborn infants (kernicterus) may be prevented by administering polyethylene glycol-conjugated bilirubin oxidase, with a longer plasma half-life which has been reported previously to oxidize bilirubin to its nontoxic components in the bloodstream.     

Recovery of aSasa tsuboiana population after mass flowering and death

The recovery process of aSasa tsuboiana population after a mass flowering and death in 1977 was investigated by 15 years of observation in the Hira Mountains, Kinki district, western Japan. Seed production was high (6600–13 800 seeds m⁻² inSasa plots and 3900 seeds m⁻² in a forest plot) but emergent seedling density was low (14–21 seedlings m⁻²), probably because of seed predation byMicrotus montebelli occurring between seed shedding and the next spring. The seedling density had decreased further by the next year and theS. tsuboiana population recovered from only a limited number of seedlings. In spite of such a low initial density, theS. tsuboiana population was able to regenerate successfully and attained the previous full stand height in 7–16 years.Miscantbus sinensis invaded and delayed the recovery ofS. tsuboiana in one plot, butS. tsuboiana became dominant as it caught up with the height ofM. sinensis. Seedling growth patterns, such as frequent tillering, the onset of rhizome extension in the early stage of seedling growth and frequent culm production from rhizomes, played important roles in the successful regeneration ofS. tsuboiana.     

An extracellular β-galactosidase secreted from cell suspension cultures of carrot. Its purification and involvement in cell wall-polysaccharide hydrolysis

β-Galactosidase (β-Galase, EC 3.2.1.23) activity has been detected in a culture medium of cell suspension cultures of carrot ( Daucus carota L. cv. Kintoki). The extracellular β-Galase (β-Galase-II) was purified to electrophoretic homogeneity from the concentrated medium using ammonium sulfate precipitation, chromatography on CM-Sephadex C-50. DEAE-Sepharose CL-6B and Sephacryl S-200HR, and preparative PAGE. The molecular mass of the purified enzyme was estimated to be 65 kDa by Sephacryl S-200HR gel-permeation, and 60 kDa by SDS-PAGE after treatment with SDS and 2-mercaptoethanol. The pI was 6.5. The K_m and V_max values for p -nitrophenyl (PNP)-β-D-galactopyranoside were 0.17 m M and 31.9 μmol (mg protein)^-1, h^-1, respectively. The optimal activity in McIlvaine's buffer occurred at pH 4.0–4.4. The enzyme activity was inhibited by Co²⁴, Cu²⁺, Hg^2-, p -chloromercuribenzoate (PCMB) and D-galactono-1,4-lactone. The enzyme acted on citrus galactan and larchwood arabinogalactan in an exo-fashion, and was slightly involved in the hydrolysis of an acidic pectic polymer containing arabinosyl and galactosyl residues and in the breakdown of cell walls isolated from carrot cell cultures.     

Origin ofd-serine present in urine of mutant mice lackingd-amino-acid oxidase activity

Summary Urine of ddY/DAO mice lackingd-amino-acid oxidase contained 5.7 times more serine than that of normal ddY/DAO⁺ mice. Most of the serine wasd-isomer. The origin of this^d-serine was examined. Oral administration of 0.02% amoxicillin and 0.004% minocycline to the ddY/ DAO^- mice for 7 days did not reduce the urinaryd-serine, indicating that thed-serine was not of intestinal bacterial origin. When the mouse diet was changed to one with different compositions, the urinaryd-serine was considerably reduced. Furthermore, starvation of the ddY/DAO^- mice for 24 hours reduced the urinaryd-serine to 33% of the original level. These results indicate that most of the urinaryd-serine comes from the diet. However, the urine of the starved ddY/DAO^- mice still contained 4.6 times mored-serine than that of the ddY/DAO⁺ mice, suggesting a part of the D-serine have an endogenous origin.