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51.
Alterations in copper and collagen metabolism in the Menkes syndrome and a new subtype of the Ehlers-Danlos syndrome 总被引:2,自引:0,他引:2
L Peltonen H Kuivaniemi A Palotie N Horn I Kaitila K I Kivirikko 《Biochemistry》1983,22(26):6156-6163
Cultured fibroblasts of 13 patients with the Menkes syndrome and two with a new subtype (type IX) of the Ehlers-Danlos syndrome (E-D IX patients) showed many very similar abnormalities in their copper and collagen metabolism. Both cell types had markedly increased copper concentrations and 64Cu incorporation, and this cation accumulated in metallothionein or a metallothionein-like protein, as previously established for Menkes cells. Histochemical staining indicated that copper was distributed diffusely throughout the cytoplasm in both cell types, this location being consistent with the accumulation in metallothionein. Both fibroblast types also had markedly low lysyl oxidase activity and distinctly increased extractability of newly synthesized collagen, whereas no abnormalities were present in cell viability, duplication rate, prolyl 4-hydroxylase activity, or collagen synthesis rate. A high negative correlation (P less than 0.001) was found in the pooled group of Menkes and E-D IX cells between cellular copper concentration (r = 0.804) or 64Cu incorporation (r = 0.863) and the logarithm of lysyl oxidase activity. There was also a high positive correlation (P less than 0.001) between cellular copper concentration and incorporation (r = 0.869). One of the two E-D IX patients was also shown to have similar changes in lysyl oxidase activity and collagen extractability in the skin biopsy specimen, suggesting that the abnormalities observed in cultured cells are similar to those present in vivo. The only distinct abnormality found in the cells of the parents of the E-D IX patients was an increased 64Cu incorporation in those of the mother, this finding being consistent with X-linked inheritance of the disorder. 相似文献
52.
Pearl Horn Cooper Irvin N. Hirshfield Werner K. Maas 《Molecular & general genetics : MGG》1969,104(4):383-390
Summary Mutants of Escherichia coli K-12 previously isolated in the authors' laboratory have reduced arginyl-tRNA synthetase activity. The mutants fall into two classes. All mutants grow slowly on arginine-free medium. On arginine-supplemented medium some mutants grow at a normal rate (Class I) while others still grow slowly (Class II). Matings were performed to located a Class I and a Class II mutation on the E. coli chromosome map, and on the basis of our results we have assigned both to one locus, argS. 相似文献
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Horoyuki Shimizu Deborah Wyatt Rebecca D. Knowles Corazon D. Bucana Eric J. Stanbridge Eugenie S. Kleinerman 《Cancer immunology, immunotherapy : CII》1989,28(3):185-192
Summary The characteristics of the binding of human monocytes to tumor cells were studied by a newly developed microassay. First, we determined the kinetics and optimal conditions of the binding. Monocytes recognized and bound to tumor cells very rapidly within 10–20 min of cellular interaction. Binding was also more efficient at 37°C suggesting that active metabolism of monocytes is required. Second, we determined that selective binding of monocytes to cells with tumorigenic phenotypes occurs. For this purpose, lymphocytic leukemia cell lines versus normal lymphocytes, and tumorigenic versus nontumorigenic hybrids from the same parental lines were compared as the targets of the binding assay. In both cases, neoplastic cells were selectively bound by monocytes. Although tumor cells were bound rapidly and selectively by monocytes, initial recognition and binding did not necessarily lead to subsequent tumor cell lysis. This is based on the observation that some tumorigenic parental and hybrid lines were avidly bound by monocytes yet not subsequently killed in a cytotoxicity assay.This work was supported in part by a grant from the National Institutes of Health CA42992 and a grant from the Kleberg foundation
Abbreviations used: [125I]IdUrd [125I]iododeoxyuridine; rIFN-, recombinant human interferon ; IL-1, interleukin 1; rTNF, recombinant human tumor necrosis factor 相似文献
60.
Forks and combs and DNA: the synthesis of branched oligodeoxyribonucleotides. 总被引:9,自引:4,他引:5
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Nucleoside phosphoramidite derivatives containing two protected primary hydroxyl functions have been incorporated into synthetic oligonucleotides as 'branching monomers'. With selective deprotection, multiple identical copies of an additional oligonucleotide can be incorporated to form fork- or comb-like structures for use as signal amplification materials in nucleic acid hybridization assays. 相似文献