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)

To elucidate catecholamine (CA) secretory dynamics in neuroblastoma, urinary excretion of CAs and their metabolites was serially measured in 6 patients aged 3 months to 3 years before and during treatment. After tumor extirpation, increased urinary CAs were promptly normalized; the reduction reflected the amount of CA production from the tumor. Urinary dopamine (DA) showed the most prominent reduction, whereas DA content in the tumor was very small, indicating that the DA produced was immediately released from the tumor and metabolized in extra-tumor tissues. In contrast, patients receiving chemotherapy continued to excrete excess DA and homovanillic acid (HVA), which were increased further at recidivation. One patient showed an inverse correlation between DA and norepinephrine (NE) excretion; a decrease in DA was associated with an increase in NE and plasma DA-beta-hydroxylase (DBH) activity. A similar inverse correlation was also noted between NE and vanillylmandelic acid (VMA) or 3-methoxy-4-hydroxyphenylglycol (MHPG) excretion, while HVA and dihydroxyphenylacetic acid (DOPAC) were positively correlated with DA excretion. Urinary HVA and VMA were lineally correlated but in a patient excreting an enormous amount of DA, urinary VMA was markedly suppressed in terms of HVA excretion. Excessive DA induced an increase in renal water output but did not enhance Na and K excretion. These results indicate that endogenous DA overload in neuroblastoma inhibits NE production by suppressing DBH activity as well as by forming VMA and MHPG. This precursor regulation appears to be the characteristic of the CA metabolic pathway.
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PMID:Suppression of norepinephrine secretion by dopamine in children with neuroblastoma: evidence for precursor inhibition in catecholamine pathway. 258 66

A modification of a Dionex System 12 ion chromatograph is described which enables organic anions (acetate and formate), inorganic cations (ammonium, sodium and potassium) and inorganic anions (chloride, nitrate and sulphate) to be determined sequentially in one measuring procedure. The modified instrument consists of a programmable controller unit, a conductimetric meter, two conductimetric detectors of the Dionex System 12 ion chromatograph, the HPIC-AS4A and HPIC-CS3 modern separation units, AMMS-1 and CMMS-1 micro-membrane suppressor columns, a unique system of valves from Dionex and two dual pumps from Biotronik. The limits of detection are between about 1 and 3 micrograms/l for chloride, nitrate and sulphate and between about 2 and 10 micrograms/l for acetate, formate, ammonium, sodium and potassium. The reliability of the method was demonstrated by analysing two NBS simulated rain water Standard Reference Materials. Some examples are given of the application of the method to the sequential determination of the main precipitation components in typical samples from urban and rural regions of the F.R.G. The ion concentrations varied between about 0.02 and 300 mg/l.
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PMID:Modification of a Dionex System 12 ion chromatograph for sequential determination of the main components in atmospheric precipitation. 260 Jan 53

Lead has been demonstrated to induce precocious glial differentiation both in vitro and in vivo. Lead-treated rat glioma (C6) and cerebellar astrocytes exhibited cytoplasmic extensions and the presence of glial endfeet after a 3-day exposure to 10(-6) to 10(-4) M PbCl2. In similar experiments no effect was noted in neuroblastoma (Neuro-2a) or on neurite outgrowth from chick spinal cord explants. This prodifferentiative effect on glia was also seen in the cerebella of postnatal rats in which the developmental expression of glial-specific glutamine synthetase activity was significantly increased up to postnatal day 12 after chronic exposure to lead from time of birth via their dam's drinking water (400 mg PbCl2/l).
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PMID:Chronic low level lead exposure precociously induces rat glial development in vitro and in vivo. 289 24

The grey scale ultrasound features of 30 cases of Wilms' tumour examined using a water delay scanner are presented. Eighty-seven percent of masses were of uniform texture, with echogenicity equal to or slightly greater than that of liver with small hypo-echoic areas. There were no totally cystic tumours in the series. In 21 cases the mass was clearly arising from the ipsilateral kidney, but in 9 cases the ipsilateral kidney could not be distinguished from the tumour. The state of the intrahepatic inferior vena cava (IVC) was correctly diagnosed in 27 cases and further evaluation was needed in two patients in whom this segment could not be demonstrated. If this segment is sonographically normal, then the IVC need not be evaluated further. Differential diagnosis is discussed, with particular reference to neuroblastoma. In the majority of patients ultrasound is the only modality needed to diagnose Wilms' tumour pre-operatively.
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PMID:Ultrasound of Wilms' tumor. 300 60

Both high and low affinity receptors for nerve growth factor (NGF) have been described, but only the former appear to mediate NGF actions and uptake. To specifically characterize the molecular identity of the high affinity site and to compare it with the low affinity site, the water-soluble carbodiimide EDC was used to cross-link 125I-NGF to NGF receptors on: rat PC12 cells, PC12nnr5 cells (PC12 mutants that have only low affinity NGF binding), SH-SY5Y human neuroblastoma cells (which have only high affinity binding sites), and cultured rat sympathetic ganglion cells. A variety of criteria were used to distinguish the two classes of affinity-labeled receptors: competition with unlabeled NGF, dissociation rate, and selective solubilization by 0.1% Triton X-100. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that cross-linking generated only a single Mr approximately 103,000 125I-NGF affinity-labeled species which represents both the low and high affinity forms of the receptor. The 125I-NGF X receptor complexes formed with both affinity classes of the receptor were quantitatively immunoprecipitated by the monoclonal anti-NGF-receptor antibody 192-IgG and both showed identical shifts in mobility when subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. These findings indicate that both high and low affinity NGF receptors possess apparently identical NGF-binding moieties. The differences between the kinetic and functional properties of the two receptor types may therefore result from their interactions with other membrane components or with cytoplasmic proteins.
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PMID:A single Mr approximately 103,000 125I-beta-nerve growth factor-affinity-labeled species represents both the low and high affinity forms of the nerve growth factor receptor. 302 71

Dopamine inhibits and serotonin stimulates adenylate cyclase activity in a neuroblastoma X Chinese hamster brain explant cell line (NCB-20). The inhibition of cyclic AMP accumulation by dopamine was blocked by pretreatment of the cells with pertussis toxin. Carbachol and bradykinin stimulated the accumulation of water-soluble inositol phosphates whereas thyrotropin-releasing hormone, vasopressin, neurotensin, and phenylephrine were without effect. Dopamine and serotonin had no significant effect on carbachol-induced phosphoinositide hydrolysis or the levels of the parent lipids within the membrane. Forskolin induced a much larger stimulation of cyclic AMP than did serotonin, and caused an increase in the levels of phosphatidylinositol-4-phosphate and phosphatidyl inositol-4,5-bisphosphate in the cell membrane.
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PMID:Activation of dopamine receptors does not affect phosphoinositide turnover in NCB-20 cells. 303 93

The role of endogenous opioid systems (endogenous opioids and opioid receptors) in human cancer was explored using an opioid antagonist paradigm and neuroblastoma cells (SK-N-MC) transplanted into nude mice. Mice inoculated with 2.5 X 10(6) neuroblastoma cells received daily injections of either 0.1 or 10 mg/kg naltrexone (=0.1 and 10 NTX groups) which blocked the opioid receptor for 6-8 hr/day or the entire 24 hr/day, respectively, or sterile water. The latency for appearance of a measurable tumor (5 mm diameter) in the 0.1 NTX group was 27% longer than controls (11 days), and the first death in this group occurred 33% later than controls (day 27). Mice inoculated with tumor cells in the 10 NTX group had an acceleration (18%) in the latency of tumor appearance and, 2 weeks after cell inoculation, 70% of the mice in this group had tumors, in contrast to 10% of the controls. At the termination of the experiment (day 45), only 33% of the 10 NTX group were alive, in contrast to 90% of the controls. Receptor binding assays using DAGO, DADLE, or EKC revealed specific saturable binding only for DADLE and EKC. NTX administration resulted in a 148-186% increase in density for both binding sites, but no changes in binding affinity. Measures of opioid levels showed that tumor tissue levels of both beta-endorphin and methionine-enkephalin were elevated 2.5 to 6.5 fold from control values in both NTX groups, whereas plasma beta-endorphin was subnormal by 4 to 6 fold. These results indicate that endogenous opioid systems regulate human neuro-oncogenesis, with opioids being active inhibitors of growth. Opioid antagonists up-regulate receptors and increase tissue levels of endogenous opioids and, under conditions in which the opioid antagonist is short-acting (e.g., 0.1 NTX), can have an exaggerated antitumor effect during the interval when the antagonist is no longer present.
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PMID:Modulation of human neuroblastoma transplanted into nude mice by endogenous opioid systems. 304 Nov 43

Current protocols for the treatment of neuroblastoma emphasize total or near total resection of tumor to improve survival. This is preferentially performed as a primary procedure, or is attempted at a second-look operation. Unfortunately, this tumor often grows to large size with invasion of the spinal canal, or encasement of major vascular or other retroperitoneal structures. A primary attempt at complete removal may result in difficult-to-control hemorrhage or injury to, or loss of, vital organs. A second-look procedure carries other intrinsic risks. It often must be performed during a period of chemotherapeutically induced hematologic and immunologic suppression. The presence of adhesions and dense scar tissue increases the complexity of the dissection. The Cavitron Ultrasonic Surgical Aspirator (CUSA) combines continuous fragmentation, irrigation, and aspiration in one instrument. Tissues high in water content are selectively fragmented and aspirated, while tissues high in collagen and elastin (such as blood vessels and pseudocapsular walls) are selectively spared. Five patients, two with large pelvic dumbell tumors, two with large intrathoracic tumors, and one with a seemingly unresectable large right adrenal tumor (crossing the midline with extensive aortocaval nodal involvement) had total or near-total resection accomplished using the CUSA. In these patients, initial resection of the relatively soft inner part of the tumor left a collapsed pseudocapsule, which was then removed under greatly improved exposure in a relatively small field. The constant aspiration virtually eliminated tumor spillage. Since most vessels were skeletonized without penetration, total blood loss was minimized. There were no intraoperative or postoperative complications.
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PMID:Resection of advanced stage neuroblastoma with the cavitron ultrasonic surgical aspirator. 306 99

Neuroblastoma cells were used to determine the effect of high carbohydrate and polyol levels on myo-inositol metabolism. The presence of elevated concentrations of glucose or sorbitol caused a significant decrease in both inositol accumulation and incorporation into phospholipid. These conditions, however, did not alter the accumulation of the other phospholipid head groups or the growth rate and water content of the cells. Two weeks of growth in either of the modified conditions was necessary to obtain a maximal effect on inositol incorporation. In contrast, growth in elevated concentrations of fructose, mannitol, or dulcitol had no effect on inositol metabolism. The reduced inositol accumulation and incorporation into lipids seen with glucose or sorbitol supplementation resulted in a decrease in the total phosphatidylinositol content of the cell without changing the levels of the other phospholipids. Kinetic analysis of cells grown in the presence of elevated glucose indicated that V'max for inositol uptake was significantly decreased with little change in the K'm. These data suggest that glucose decreases myo-inositol uptake in this system by noncompetitive inhibition. Cells grown in the presence of increased glucose also had elevated levels of intracellular sorbitol and decreased levels of myo-inositol. These results suggest that the high levels of glucose and sorbitol which exist in poorly regulated diabetes may be at least partially responsible for diabetic neuropathy via a reduction in the cellular content of myo-inositol and phosphatidylinositol. This system may be a useful model to determine the effect of reduced inositol phospholipid levels on neural cell function.
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PMID:myo-Inositol metabolism in 41A3 neuroblastoma cells: effects of high glucose and sorbitol levels. 309 18

The continuous turnover of membrane phospholipids requires a steady supply of biosynthetic precursors. We evaluated the effects of decreasing extracellular Na+ concentration on phospholipid metabolism in cultured neuroblastoma (N1E 115) cells. Incubating cultures with 145 to 0 mM NaCl caused a concentration-dependent inhibition of [32P]phosphate uptake into the water-soluble intracellular pool and incorporation into phospholipid. Phospholipid classes were differentially affected; [32P]phosphate incorporated into phosphati-dylethanolamine (PE) and phosphatidylcholine (PC) was consistently less than into phosphatidylinositol (PI) and phosphatidylserine (PS). This could not be attributed to decreased phospholipid synthesis since under identical conditions, there was no effect on arachidonic acid or ethanolamine incorporation, and choline utilization for PC synthesis was increased. The effect of Na+ was highly specific since reducing phosphate uptake to a similar extent by incubating cultures in a phosphate-deficient medium containing Na+ did not alter the relative distribution of [32P]phosphate in phospholipid. Of several cations tested only Li+ could partially (50%) replace Na+. Incubation in the presence of ouabain or amiloride had no effect on [32P]phosphate incorporation into phospholipid. The differential effects of low Na+ on [32P]phosphate incorporation into PI relative to PC and PE suggests preferential compartmentation of [32P]phosphate into ATP in pools used for phosphatidic acid synthesis and relatively less in ATP pools used for synthesis of phosphocholine and phosphoethanolamine, precursors of PC and PE, respectively. This suggestion of heterogeneous and distinct pools of ATP for phospholipid biosynthesis, and of potential modulation by Na+ ion, has important implications for understanding intracellular regulation of metabolism.
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PMID:Compartmentation of phosphorylated precursors of phospholipid biosynthesis in cultured neuroblastoma cells. 311 15


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