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  • 1
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    Unknown
    Chapel Hill, N.C. : Periodicals Archive Online (PAO)
    Social Forces. 57:2 (1978:Dec.) 762 
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  • 2
    ISSN: 1432-0843
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The glycoproteins on the surface of HL-60/S wild-type, drug-sensitive human leukemia cells and HL-60/AR anthracycline-resistant cells which do not overexpress the P-glycoprotein, were characterized by labeling with [35S]-methionine, NaB[3H4], phosphorus 32, or sodium iodide I 125. HL-60/S and HL-60/AR cell lysates and membrane fractions tagged with [35S]-methionine or phosphorus 32 showed no significant differences in their protein patterns as analyzed by sodium dodecyl sulfatepolyacrylamide gel electrophoresis (SDS-PAGE) and by autoradiography. HL-60/S cells labeled with NaB[3H4] yielded glycoproteins that were smeared predominantly in the molecular-weight range of 210,000 and 160,000 Da, with pI values ranging between pH 4 and pH 4.4. In contrast, NaB[3H4]-labeled HL-60/AR cells showed 7–8 discrete glycoproteins within a molecular-weight range of 170,000 and 140,000 Da, with pI values also ranging between pH 4 and pH 4.4. In addition, [3H]-glucosamine incorporation into HL-60/S and HL-60/AR cells revealed that the latter showed lower uptake of [3H]-glucosamine than did the former. Following treatment with tunicamycin, [3H]-glucosamine uptake in HL-60/S cells decreased, whereas that in HL-60/AR cells remained unchanged. Surface-membrane radioiodination of HL-60/S and HL-60/AR cells showed two distinct protein electrophoretic patterns, with differences being observed in both the high-(220–95 kDa) and low-molecular-weight ranges (21 kDa). Flow cytometric analysis of HL-60/S and HL-60/AR cells using myeloid and lymphoid antigen-specific antibodies demonstrated no antigenic differences between HL-60/S and HL-60/AR cells. HL-60/S cells incubated in the presence of tunicamycin, an inhibitor ofN-linked glycosylation, or the protein kinase C agonist phorbol 12-myristate 13-acetate (PMA) developed a glycoprotein pattern similar to that observed in HL-60/AR cells. In addition, tunicamycin treatment of HL-60/S cells decreased daunorubicin (DNR) retention and altered its intracellular distribution as compared with that in HL-60/AR cells. These data indicate that HL-60/AR cells do not possess either de novo or amplified high-molecular-weight surface-membrane proteins; instead, existing proteins are hypoglycosylated. These results also show that HL-60/AR cells exhibit the multidrug-resistant phenotype in association with altered membrane glycoproteins of both high (220–95 kDa) and low molecular weight (21 kDa), but without overexpression of the P-glycoprotein. Furthermore, in HL-60/S cells, the multidrug-resistant phenotype is partially inducible by inhibition ofN-linked glycosylation of cell-surfac proteins.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Cancer immunology immunotherapy 13 (1982), S. 85-88 
    ISSN: 1432-0851
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Forty-eight patients with acute myeloblastic leukemia in remission were treated with immunotherapy in addition to remission-maintenance chemotherapy. The first 16 patients were treated with weekly BCG and a leukemia cell vaccine (group 1). The next 32 patients were randomly allocated to receive BCG and a leukemia cell vaccine given once monthly (group 2) or BCG given monthly with no leukemia cell vaccine (group 3). There was no significant difference in remission duration or survival between the randomly allocated groups (2 and 3). Comparisons with group 1 are limited by the non-random allocation to this group, but selection bias was unlikely and clinical features were similar in the three patient groups. No significant difference in remission duration or survival was seen amongst the three groups studied. There was no advantage in the addition of leukemia cell vaccine (groups 1 and 2) to BCG alone (group 3) and no advantage to weekly (group 1) versus monthly immunotherapy (groups 2 and 3). Only 7 of the 48 patients achieved a second remission, and 4 of these were short-term partial remissions.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0851
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Immunological data were obtained during the course of a randomized trial comparing intrapleural BCG plus oral isoniazid (INH) with intrapleural saline plus oral placebo after resection of stage I non-small cell lung cancer. Immunological testing with a variety of assays was carried out with good standardization among six collaborating laboratories and with good reproducibility within each laboratory. Those patients with larger tumors tended to have higher initial white cell counts. The percentage of lymphocytes in the differential was greatest in those with non-squamous cancer histology. Otherwise, no associations were found between initial immunologic parameters and baseline variables. The main effect of BCG/INH therapy was to cause statistically significant increases in purified protein derivative (PPD) skin test induration and PPD in vitro blastogenesis compared with controls. Other skin tests and in vitro assays increased more in the saline/placebo control group, but these treatment differences were usually not statistically significant. Initial white count and neutrophil count elevations were found to be associated with increased risk of recurrence. Even after adjustment for treatment and tumor stage, initial neutrophil count elevation was associated with increased risk of recurrence. Surprisingly, a low 29° C T cell rosette index was associated with a decreased risk of recurrence, though the differences were minimal. Serial immunological tests were carried out to evaluate their potential for monitoring disease recurrence. White count elevations continued to be significantly associated with increased risk of recurrence, but more follow-up data are needed before other associations can be assessed.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1573-4986
    Keywords: glycosyltransferase ; O-glycan ; β6-N-acetylglucosaminyltransferase ; α3-sialyltransferase ; specificity ; leukemia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract To elucidate control mechanisms ofO-glycan biosynthesis in leukemia and to develop biosynthetic inhibitors we have characterized core 2 UDP-GlcNAc:Galβ1-3GalNAc-R(GlcNAc to GalNAc) β6-N-acetylglucosaminyl-transferase (EC 2.4.1.102; core 2 β6-GlcNAc-T) and CMP-sialic acid: Galβ1-3GalNAc-R α3-sialyltransferase (EC 2.4.99.4; α3-SA-T), two enzymes that are significantly increased in patients with chronic myelogenous leukemia (CML) and acute myeloid leukemia (AML). We observed distinct tissue-specific kinetic differences for the core 2 β6-GlcNAc-T activity; core 2 β6-GlcNAc-T from mucin secreting tissue (named core 2 β6-GlcNAc-T M) is accompanied by activities that synthesize core 4 [GlcNAcβ1-6(GlcNAcβ1-3)GalNAc-R] and blood group I [GlcNAcβ1-6(GlcNAcβ1-3)Galβ-R] branches; core 2 β6-GlcNAc-T in leukemic cells (named core 2 β-GlcNAc-T L) is not accompanied by these two activities and has a more restricted specificity. Core 2 β6-GlcNAc-T M and L both have an absolute requirement for the 4- and 6-hydroxyls ofN-acetylgalactosamine and the 6-hydroxyl of galactose of the Galβ1-3GalNAcα-benzyl substrate but the recognition of other substituents of the sugar rings varies, depending on the tissue. α3-sialytransferase from human placenta and from AML cells also showed distinct specificity differences, although the enzymes from both tissues have an absolute requirement for the 3-hydroxyl of the galactose residue of Galβ1-3GalNAcα-Bn. Galβ1-3(6-deoxy)GalNAcα-Bn and 3-deoxy-Galβ1-3GalNAcα-Bn competitively inhibited core 2 β6-GlcNAc-T and α3-sialyltransferase activities, respectively.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1573-4986
    Keywords: GlcNAc-transferase V ; substrate specificity ; inhibition ; leukaemia ; N-linked glycans
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract UDP-GlcNAc:GlcNAc β1-2Manα1-6R (GlcNAc to Man) β1,6-N-acetylglucosaminyltransferase V (GlcNAc-T V) adds a GlcNAcβ1-6 branch to bi- and triantennaryN-glycans. An increase in this activity has been associated with cellular transformation, metastasis and differentiation. We have used synthetic substrate analogues to study the substrate specificity and inhibition of the partially purified enzyme from hamster kidney and of extracts from hen oviduct membranes and acute myeloid leukaemia leukocytes. All compounds with the minimum structure GlcNAcβ1-2Manα1-6Glc/Manβ-R were good substrates for GlcNAc-T V. The presence of structural elements other than the minimum trisaccharide structure affected GlcNAc-T V activity without being an absolute requirement for activity. Substrates with a biantennary structure were preferred over linear fragments of biantennary structures. Kinetic analysis showed that the 3-hydroxyl of the Manα1-3 residue and the 4-hydroxyl of the Manβ- residue of the Manα1-6(Manα1-3)Manβ-RN-glycan core are not essential for catalysis but influence substrate binding. GlcNAcβ1-2(4,6-di-O-methyl-)Manα1-6Glcβ-pnp was found to be an inhibitor of GlcNAc-T V from hamster kidney, hen oviduct microsomes and acute and chronic myeloid leukaemia leukocytes.
    Type of Medium: Electronic Resource
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