Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pollution from the Kjeldahl method for crude protein has been reduced by substituting a low level of copper (0.04 g CuSO4) for the mercury (0.7 g HgO) specified in the AOAC official method, 2.049. Adjustments were made in the salt-acid ratio so the new system could handle hard-to-digest samples in a reasonable time. The new method was rugged for lysine. HCl. It is designed to be used for crude protein in feeds or similar Kjeldahl work. Precision and accuracy were equal to or better than that for the official method in a study of 17 samples analyzed in duplicate on 3 different days. The following samples were used in the study: lysine. HCl, tryptophan, NBS standards, urea, meals, mixed feeds, grains, and forage. The average per cent nitrogen found was 9.52 by the official method and 9.53 by the copper method. The average standard deviation was 0.038 by the official method and 0.033 by the copper method, giving the corresponding relative standard deviations of 0.40 and 0.35%.
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PMID:Pollution-reduced Kjeldahl method for crude protein. 103 79

Chromatin was prepared from isolated nuclei of proliferating and differentiated cultures of C1300 mouse neuroblastoma cells. Differentiation was induced by serum withdrawal or treatment with dibutyryl cyclic AMP. The ability to support DNA-dependent RNA synthesis when assayed in a cell-free system is three times greater for chromatin from proliferating cells. Histones isolated from proliferating and differentiated cells were fractionated electrophoretically. The relative amounts of proteins present in the five major histone fractions were similar. In contrast, there were significant differences in the nonhistone chromosomal proteins synthesized and associated with the genome of proliferating and differentiating neuroblastoma cells. Such differences are reflected by modifications in the electrophoretic banding patterns and in incorporation of [3H]tryptophan into various molecular weight classes of nonhistone chromosomal polypeptides. A functional relationship between changes in the nonhistone chromosomal proteins and variations in the transcriptional activity accompanying differentiation of neuroblastoma cells may exist.
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PMID:Gene expression in mouse neuroblastoma cells: properties of the genome. 105 97

A semiautomated method consisting of digestion of animal feeds in a block digestor and determination of ammonia by ammonia-salicylate reaction has been studied collaboratively, along with the official final action Kjeldahl method, sec. 7.016. Each collaborator analyzed 16 feed samples, tryptophan, ammonium dihydrogen phosphate NBS standard, and ammonium sulfate primary standard. Statistical analysis showed that the 2 methods agreed. The semiautomated method has been adopted as official first action.
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PMID:Collaborative study of a semiautomated method for the determination of crude protein in animal feeds. 124 27

An automated macro Kjeldahl instrument determines per cent protein at the rate of 20 samples/hr. The methodology involved is similar to the present official final action Kjeldahl method, sec. 7.016. The 2 methods were compared in a collaborative study. Sixteen animal feeds, 4 meats, tryptophan, ammonium dihydrogen phosphate NBS standard, and ammonium sulfate primary standard were analyzed by the participating laboratories. The data were agreement between the 2 methods. The automated method has been adopted as official first action for the determination of crude protein in feeds, plants, and cereal foods.
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PMID:Collaborative study of an automated method for the determination of crude protein in animal feeds. 124 29

Bordetella pertussis produces a calmodulin-stimulated adenylyl cyclase that invades animal cells and raises intracellular cAMP levels [Confer, D. L., & Eaton, J. W. (1982) Science 217, 948-950; Shattuck, R. L., & Storm, D. R. (1985) Biochemistry 24, 6323-6328]. The mechanism for invasion of animal cells by this enzyme has not been defined, but there is considerable evidence that it does not enter by receptor-mediated endocytosis [Gordon, V. M., Leppla, S. H., & Hewlett, E. L. (1988) Infect. Immun. 56, 1066-1069; Donovan, M. G., & Storm, D. R. (1990) J. Cell. Physiol. 145, 444-449]. In this study, the importance of high-affinity calmodulin (CaM) binding for entry of the enzyme into neuroblastoma cells was evaluated using a mutant enzyme that has significantly lower affinity for calmodulin than the wild-type enzyme. Oligonucleotide-directed site-specific mutagenesis was used to create a point mutant at a critical tryptophan residue (Trp-242) within the proposed CaM binding domain of the B. pertussis adenylyl cyclase. Substitution of Trp-242 with Glu lowered the apparent affinity of the enzyme for calmodulin by 250-fold; however, the maximal enzyme activity in the presence of saturating calmodulin was equivalent to the wild-type enzyme. The Glu-242 mutant adenylyl cyclase was returned to B. pertussis by homologous recombination, and the enzyme produced by this strain was examined for invasion of neuroblastoma cells. Although the mutant enzyme stimulated the production of intracellular cAMP in neuroblastoma cells, the rate of cAMP accumulation was at least 10-fold lower than that caused by the wild-type enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:High-affinity calmodulin binding is required for the rapid entry of Bordetella pertussis adenylyl cyclase into neuroblastoma cells. 139 Jun 75

The human neuroblastoma cells NB69 are a catecholamine-rich cell line with pharmacological properties similar to dopamine neurons. This cell line was used to study the neurotoxicity of levodopa on catecholamine neurons. Levodopa, at 50 x 10(-6) M or higher concentrations, produced a dose- and time-dependent reduction in the number of live cells, [3H]thymidine uptake, levels of protein and DNA, and an enhancement of the quinone formation. This is a specific effect of levodopa since it did not happen in NB69 cells incubated with equimolar concentrations of leucine and tryptophan. Treatment with deprenyl, an inhibitor of monoamine oxidase type B, partially prevented levodopa neurotoxicity, suggesting that the mechanism of toxicity was, at least in part, related to an increase in the metabolism of dopamine catalyzed by monoamine oxidase.
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PMID:Neurotoxicity of levodopa on catecholamine-rich neurons. 155 63

Interferon-gamma-induced tryptophan metabolism of human macrophages was compared to ten human neoplastic cell lines of various tissue origin and to normal dermal human fibroblasts. Tryptophan and metabolites were determined in supernatants of cultures, after incubation for 48 h, by high-performance liquid chromatography with ultraviolet and fluorescence detection. With the exception of two cell lines (Hep G 2, hepatoma and CaCo 2, colon adenocarcinoma) in all of the ten other cells and cell lines tryptophan degradation was induced by interferon-gamma. Five of these ten formed only kynurenine (SK-N-SH, neuroblastoma; T 24, J 82, bladder carcinoma; A 431, epidermoid carcinoma; normal dermal fibroblasts), three formed kynurenine and anthranilic acid (U 138 MG, glioblastoma; SK-HEP-1, hepatoma; A 549, lung carcinoma). Only one line, A 498 (kidney carcinoma) showed the same pattern of metabolites as macrophages (kynurenine, anthranilic acid and 3-hydroxyanthranilic acid). Interferon-gamma regulated only the activity of indoleamine 2,3-dioxygenase. All other enzyme activities detected were independent of interferon-gamma, as shown by the capacity of the cells to metabolize L-kynurenine or N-formyl-L-kynurenine. Increasing the extracellular L-tryptophan concentration resulted in a marked induction of tryptophan degradation by macrophages. Contrarily, a significant decrease of the tryptophan degrading activity was observed when the extracellular L-tryptophan concentration was increased 2-fold with SK-N-SH, T 24 and J 82, 4-fold with A 431 and A 549 and 10-fold with U 138 MG and SK-HEP-1. The activity was unaffected by extracellular L-tryptophan with dermal fibroblasts and A 498. Though interferon-gamma was the most potent inducer of tryptophan metabolism, interferon-alpha and/or -beta showed small but distinct action on some of the cells. In all cells which reacted to interferon-gamma by enhanced expression of class I and/or class II major histocompatibility complex antigens tryptophan degradation was also inducible. These results demonstrate that induction of indoleamine 2,3-dioxygenase is a common feature of interferon-gamma action, that the extent of this induction is influenced by extracellular L-tryptophan concentrations and that indoleamine 2,3-dioxygenase is the only enzyme in the formation of 3-hydroxyanthranilic acid from tryptophan which is regulated by interferon-gamma.
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PMID:Characteristics of interferon induced tryptophan metabolism in human cells in vitro. 250 Sep 76

Peripherin, an intermediate filament protein, described recently, is expressed in well defined neuronal populations. We studied the phosphorylation, in vivo, of this protein in mouse neuroblastoma NIE 115 cell line and in sympathetic neurons labelled with [32P]-orthophosphate. The autoradiograms of proteins separated on two-dimensional polyacrylamide gels were compared with the Coomassie-blue stainings. The results show that peripherin occurs as a mixture of phosphorylated and non-phosphorylated isoforms, and that these forms coexist in both differentiated and non-differentiated cells. We demonstrate by cleavage at the unique tryptophan residue, a characteristic shared by most other intermediate filament proteins (IFP), that the phosphorylation sites are located on the amino-terminal half of peripherin as it is for vimentin and desmin. These results are discussed in relation to the organization of the filamentous network constituted by peripherin.
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PMID:Phosphorylation of peripherin, an intermediate filament protein, in mouse neuroblastoma NIE 115 cell line and in sympathetic neurons. 271 95

Trp-155 in bovine DNase A (EC 3.1.4.5) appeared to be unessential for the enzymatic activity for the following reasons: (1) A unique peptide which suggests the environmental difference of Trp-155 was obtained from porcine pancreatic DNase A. (2) Inactivation of the porcine DNase A by NBS modification was fairly paralleled with a decrease in the CD signal, which is characteristic of the "buried" tryptophan in the hydrophobic region (trp-191 in bovine DNase) but not of tryptophans in the hydrophilic portion. Binding of DNase to the poly I: poly C double helix confirmed the important role of this tryptophan.
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PMID:Functional evaluation of tryptophanyl residues of bovine and porcine pancreatic deoxyribonucleases. 345 85

Rubrophilin, a unique brain specific polypeptide, was purified to apparent homogeneity from microsomal fractions of bovine brains. The peptide stains pink with Coomassie Brilliant Blue R-250 (C.I. No. 42660) under specific conditions, has an apparent Mr of 53,000, and is acidic with an apparent pI of 4.9. The purification involves initial solubilization of delipidated microsomes in sodium dodecyl sulfate, followed by ammonium sulfate fractionation, reversed ammonium sulfate gradient elution from diatomaceous earth, gel filtration on polyacrylamide (Biogel P-200), gradient elution chromatography from hydroxylapatite, and reverse-phase chromatography from phenyl-Sepharose. A yield of about 5 mg of rubrophilin was obtained from 9 g of microsomal proteins. Amino acid analysis shows that rubrophilin contains only nine amino acids with residues/mol as follows: alanine (102), glutamic acid (97), lysine (65), proline (55), aspartic acid (48), glycine (44), serine (37), threonine (35), and valine (10). Cysteine, methionine, tryptophan, tyrosine, isoleucine, phenylalanine, histidine, and arginine could not be detected. Relative rubrophilin content of vertebrate brains was as follows: mammals greater than birds greater than reptiles greater than fishes. It is present in mouse retina and human neuroblastoma cell cultures but could not be detected in octopus optic lobe or in cultured C-6 rat glioma cells.
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PMID:Purification and properties of rubrophilin: a novel brain specific membrane polypeptide. 380 7


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