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)

The addition of 1% (w/v) carboxymethyl cellulose to the culture medium induces the formation of neurites of clone N18 neuroblastoma cells even in the presence of normal (5-10%) serum supplement concentrations, which rivals that previously observed by growth in low 0.1% serum. Heavy metal ions associated with the carboxymethyl cellulose were responsible for small increases in the sizes of cell bodies during treatment. Pretreatment of the PC12 pheochromocytoma line of neuroblasts with carboxymethyl cellulose for 1 day prior to their stimulation with nerve growth factor resulted in an acceleration in the rate, but not extent, of neurite outgrowth.
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PMID:Carboxymethyl cellulose stimulation of neurite outgrowth of neuroblastoma cells in culture. 57 24

We describe the determination of 3-methoxy-4-hydroxy-phenylacetic acid, 3-methoxy-4-hydroxyphenylamandelic acid, and 3-methoxy-4-hydroxyphenylethylene glycol in amniotic fluid by means of mass fragmentography, with use of deuterated internal standards. The results expressed in terms of absolute concentration and creatinine concentration, are given as a function of gestational age. In the 15th to 17th week, concentrations in amniotic fluid are a reflection of those in the mother's serum, whereas in the 32nd to 40th week, these concentrations, expressed in terms of creatinine, are similar to those found in the urine of newborns. We discuss the possible usefulness of the determination of catecholamine metabolites in amniotic fluid in the diagnosis of congenital neuroblastoma, maternal pheochromocytoma, and underdevelopment.
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PMID:Mass-fragmentographic determination of catecholamine metabolites in amniotic fluid and its possible clinical usefulness. 70 17

We report the determination of 3-methoxy-4-hydroxyphenylpyruvic acid, 3,4-dihydroxyphenylmandelic acid, and 3,4-dihydroxyphenylethylene glycol in urine, by use of gas chromatography/mass spectrometry in combination with a simple purification method and deuterium-labeled internal standards. Normal excretion values in terms of creatinine, expressed as a function of age, are given, together with results obtained for patients with neuroblastoma, pheochromocytoma, or parkinsonism treated with L-DOPA + peripheral decarboxylase inhibitor, and for a patient receiving dopamine. We were unable to identify 3, 4-dihydroxyphenyllactic acid in urine. The results obtained and their relation to other catecholamine metabolites and catecholamine-precursor metabolites in urine are discussed.
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PMID:Determination of 3-methoxy-4-hydroxyphenylpyruvic acid, 3,4-dihydroxyphenylethylene glycol, and 3,4-dihydroxyphenylmandelic acid in urine by mass fragmentography, with use of deuterium-labeled internal standards. 70 35

Ultrastructural features of neoplastic cells can provide clues for correct diagnosis when light microscopy fails. Secretory granules are characteristic in the following tumors: mucin granules in poorly differentiated adenocarcinomas, zymogen granules in acinic cell carcinomas, lysosomal granules in prostatic carcinomas, melanin granules in malignant melanoma, carcinoid, islet cell tumors, pheochromocytoma, and neuroblastoma granules in the corresponding neoplasms. Among cytoplasmic organelles, rough surfaced endoplasmic reticulum characterizes adrenocortical, ovarian, and hepatocellular carcinomas and plasmacytomas. Tonofibrils are characteristic of squamous cell carcinomas. Glycogen deposits distinguish Ewing's sarcoma from lymphoreticular neoplasms. Intercellular relationships and membrane specialization are important features in the differential diagnosis of various undifferentiated tumors. The frequent resolution of difficult diagnostic problems by electron microscopy outweighs the disadvantages of this technique, such as the expense and time required.
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PMID:The usefulness of electron microscopy in the diagnosis of human tumors. 115 Feb 21

Quantitative analytical methods for plasma catecholamines and their conjugates by the use of gas-liquid chromatography have been developed. Epinephrine and dopamine have also been determined by mass fragmentography. The contents of catecholamines in the plasma of normal adults and patients with hypertension, neuroblastoma and pheochromocytoma have been demonstrated.
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PMID:Gas-liquid chromatographic and mass fragmentographic determination of catecholamines in human plasma. 117 83

Plasma 3-O-methylated catecholamines, i.e. 3-methoxytyramine, normetanephrine and metanephrine, were separated from catecholamines by passing through alumina and further purified by adsorbing on weakly acidic resin and Amberlite XAD-4. The amines were trifluoroacetylated and determined by gas chromatography or mass fragmentography. Tracer quantities of tritiated 3-MT, NMN or MN were used as internal standards for total recovery estimations. The contents of 3-O-methylated catecholamines in the plasma of normal persons and patients with hyperthyroidism, hypertension, neuroblastoma and pheochromocytoma were measured.
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PMID:Gas-liquid chromatographic and mass fragmentographic determination of 3-O-methylated catecholamines in human plasma. 117 84

Presentation of a series of 14 cases of neural crest derived tumours located in the retroperitoneal space in adult patients (five pheochromocytoma, six paraganglioma, two ganglioneuroma, and one neuroblastoma), and review and update of the diagnostic and therapeutic aspects. All pheochromocytoma cases presented high BP and the classic triad of sudation, tachycardia and headaches, as well as high levels of blood and urine catecholamines and/or their metabolites. CAT, ultrasound scanning and 123MIBG were the main diagnostic techniques used. All four paraganglioma were functioning and generally located surrounding both kidneys (one case was paired). No malignancy was found in any of the 11 tumours while controls remain with normal BP and normal levels of urine catecholamine metabolites. None of the two ganglioneuromas showed specific signs and symptoms but were diagnosed accidentally. The one neuroblastoma was juxtavesical showing a highly unfavourable evolution in spite of radical surgery, radiotherapy and multiple chemotherapy and the patient died within 16 months with local recurrence and haematogenous dissemination to bones and lungs.
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PMID:[Neural crest derived retroperitoneal tumors. General review]. 131 88

GTP cyclohydrolase I exhibits a positive homotropic cooperative binding to GTP, which raises the possibility of a role for GTP in regulating the enzyme reaction (Hatakeyama, K., Harada, T., Suzuki, S., Watanabe, Y., and Kagamiyama, H. (1989) J. Biol. Chem. 264, 21660-21664). We examined whether or not the intracellular GTP level is within the range of affecting GTP cyclohydrolase I activity, using PC-12 rat pheochromocytoma and IMR-32 human neuroblastoma cells. Since GTP cyclohydrolase I was the rate-limiting enzyme for the biosynthesis of tetrahydrobiopterin in these cell lines, the intracellular activities of this enzyme were reflected in the tetrahydrobiopterin contents. We found that the addition of guanine or guanosine increased GTP but not tetrahydrobiopterin in these cells. On the other hand, three IMP dehydrogenase inhibitors, tiazofurin, 2-amino-1,3,4-thiadiazole, and mycophenolic acid, decreased both GTP and tetrahydrobiopterin in a parallel and dose-dependent manner, and these effects were reversed by the simultaneous addition of guanine or guanosine. There was no evidence suggesting that these inhibitors inhibited other enzymes involved in the biosynthesis and regeneration of tetrahydrobiopterin. Comparing intracellular activities of GTP cyclohydrolase I in the inhibitor-treated cells with its substrate-velocity curve, we estimated that the intracellular concentration of free GTP is 150 microM at which point the activity of GTP cyclohydrolase I is elicited at its maximum velocity. Below this GTP concentration, GTP cyclohydrolase I activity is rapidly decreased. Therefore GTP can be a regulator for tetrahydrobiopterin biosynthesis.
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PMID:IMP dehydrogenase inhibitors reduce intracellular tetrahydrobiopterin levels through reduction of intracellular GTP levels. Indications of the regulation of GTP cyclohydrolase I activity by restriction of GTP availability in the cells. 135 83

It is well documented that cold stress induces a rapid trans-synaptically mediated increase in the relative abundance of rat adrenomedullary tyrosine hydroxylase (TH) mRNA. To investigate the transcriptional mechanisms regulating the cold stress response, we have employed a gel mobility shift assay, using DNA fragments prepared from the proximal 5' flanking region of the bovine TH gene as a heterologous molecular probe. In pilot studies, this region of the bovine TH promoter (nucleotides -246 to +21) was fused to the bacterial reporter gene, chloramphenicol acetyltransferase, and the chimeric construct transfected into human neuroblastoma SK-N-BE(2)-C, hepatoma HepG2, and rat pheochromocytoma PC-12 cells. Results of this analysis indicate that the proximal 5' flanking region of the bovine TH gene contains sufficient information to drive transient reporter gene expression in both human and rat catecholaminergic clonal cell lines. The findings derived from the gel mobility shift studies demonstrate that cold exposure causes rapid and selective alterations in the binding of adrenomedullary nuclear proteins to the proximal 5' flanking region of the TH gene. The most striking cold stress-induced alteration in DNA/nucleoprotein binding occurs in a region of the TH promoter (nucleotides -246 to -189) which contains an element bearing marked sequence similarity to an AP1 binding site and is highly conserved among animal species. This alteration occurs within 1 hr of cold exposure and persists for up to 48 hr after the onset of stress. The results of adrenal denervation experiments indicate that the cold-induced change in DNA/nucleoprotein binding is neurally mediated, requiring intact sympathetic innervation of the gland.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cold-induced alterations in the binding of adrenomedullary nuclear proteins to the promoter region of the tyrosine hydroxylase gene. 136 May 41

A phase III clinical study of 131I-metaiodobenzylguanidine (131I-MIBG) was performed in 66 patients with tumors of sympathetic and adrenomedullary origin, including 32 patients with suspected pheochromocytoma, 25 with suspected neuroblastoma, 7 pre- or postoperative medullary carcinoma of the thyroid and each with carcinoid and suspected Sipple's syndrome. A total of 150 sites which were confirmed for presence (72 sites) or absence (78 sites) of tumors were examined on 131I-MIBG scintigrams. True positive ratio of the scintigraphy was 84.7% (61/72) and true negative ratio was 94.9% (74/78). Positive scintigraphy was obtained in 86.5% (32/37) of pheochromocytoma, 78.6% (22/28) of neuroblastoma and 100% (6/6) of medullary carcinoma of the thyroid. Accumulation of 131I-MIBG was seen in 16.8% of normal adrenal glands. Neither adverse reactions nor abnormal laboratory findings were noted in relation to 131I-MIBG injections. Our study indicates that 131I-MIBG is a safe and clinically useful radiotracers for the visualization and localization of tumors of sympathetic and adrenomedullary origin.
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PMID:[The assessment of clinical usefulness of 131I-MIBG scintigraphy for localization of tumors of sympathetic and adrenomedullary origin--a report of multicenter phase III clinical trials]. 136 May 49


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