Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The diagnosis of pheochromocytoms is still made only post mortem in a high percentage of the cases. It is important to know both the diversity of clinical forms (of the 16 cases investigated 13 (80%) presented permanent AH, of which 12 cases with paroxysmal attacks, followed by collapse only in one case, and 3 (20%) with paroxysmal AH on a normotensive background) and the severity of cardiovascular accidents, which increases twofold during crises (arrhythmias, left ventricular failure, coronary insufficiency, cerebrovascular strokes, secondary adrenalinic shocks). These complications are preceded by the "alarm syndrome". The preoperatory treatment is associated: blocking of adrenergic alpha-receptors and beta-receptors; correction of hypovolemia, also applied during the surgical phase I (until the venous ligature is made and the tumor excised) under continuous monitoring (ECG, ABP and central venous pressure). In phase II vasoplegin should be promptly corrected by nor. E+E, and corticoids.
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PMID:Disorders induced by pheochromocytoma in the cardiovascular system. A therapeutic approach. 0 88

Immunological tolerance to Gross virus-specific transplantation antigens in rats given neonatae transfer of donor lymphoid cells beneath the kidney capsule of syngeneic recipient rats. Immune or normal donor cells invariably developed a cell-mediated immune reaction in kidneys of GV-tolerant recipients, presumably against GV antigens present on the surface of recipient lymphoid cells in the kidney. Spleen and lymph node cells from tolerant rats failed to develop a reaction in tolerant recipients, but developed a strong reaction to histoincompatible antigens in the kidneys of semisyngeneic tolerant rats. The immunologically tolerant state in the rats could be broken by adoptive transfer of spleen and lymph node cells from syngeneic rats immunized with GV-induced lymphoma cells. Immunotherapy of a GV-induced and also a GV-infected methylcholanthrene-induced fibrosarcoma growing in tolerant rats was successful when immune spleen and lymph node cells were administered i.p. 3 days after s.c. inoculation of 2 X 10(7) tumor cells in the case of the lymphoma, and 1 day after inoculation of 5 X 10(6) tumor cells in the case of the fibrosarcoma.
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PMID:Adoptive immunotherapy of a Gross virus producing lymphoma and a methylcholanthrene-induced fibrosarcoma in tolerant rats. 1 76

Three new tissue culture cell lines, CHP-100, CHP-126, and CHP-134, have been established from explant cultures of human neuroblastoma. The cell lines have been characterized with respect to morphology, chromosomes constitution, growth, neural enzyme content, and their ability to grow in nude mice. The cells grow as dense masses comprised of fibroblast-or neuroblast-like cells with small processes. The cell lines differ in their neural enzyme acitivity. The chromosomal content of the 3 cell lines is near diploid, and all are capable of forming tumors in nude mice. The morphological findings indicate that the cells in culture resemble those found in the tumor, and the enzyme activities are consistent with those of nervous tissue. This the morphological, biochemical, and tumorigenic properties confirm that the 3 cell lines are neoplastic cells of neural origin.
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PMID:Establishment and characterization of human neuroblastoma cell lines. 1 79

The objective of this investigation was to throw light on the biological behavior and metabolic regulation of hepatic enzymes of the nonoxidative branch of the pentose phosphate pathway. The activities of transaldolase (EC 2.2.1.2) and trasketolase (EC 2.2.1.1) Were compared in biological conditions that involve modulation of gene expression such as in starvation, in differentiation, after partial hepatectomy, and in a spectrum of hepatomas of different growth rates. The enzyme activities were determined under optimal kinetic conditions by spectrophotometric methods in the 100,000 X g supernatant fluids prepared from tissue homogenates. The kinetic properties of transaldolase and transketolase were similar in normal liver and in rapidly growing hepatoma 3924A. For transaldolase, apparent Km values of 0.13 mM (normal liver) and 0.17 mM (hepatoma) were observed for erythrose 4-phosphate and of 0.30 to 0.35 mM for fructose 6-phosphate. The pH optima in liver and hepatoma were at approximately 6.9 to 7.2. For the transketolase substrates, ribose 5-phosphate and xylulose 5-phosphate, the apparent Km values were 0.3 and 0.5 mM, respectively, in both liver and hepatoma. A broad pH optimum around 7.6 was observed in both tissues. In organ distribution studies, enzyme activities were measured in liver, intestinal mucosa, thymus, kidney, spleen, brain, adipose tissue, lung, heart, and skeletal muscle. Taking the specific activity of liver as 100%, transaldolase activity was the highest in intestinal mucosa (316%) and in thymus (219%); it was the lowest in heart (53%) and in skeletal muscle (21%). Transketolase activity was highest in kidney (155%) and lowest in heart (26%) and skeletal muscle (23%). Starvation decreased transaldolase and transketolase activities in 6 days to 69 and 74%, respectively, of those of the liver of the normal, fed rat. This was in the same range as the decrease in the protein concentration (66%y. In the liver tumors, transaldolase activity was increased 1.5- to 3.4-fold over the activities observed in normal control rat liver. Transketolase activity showed no relationship to tumor proliferation rate. In the regenerating liver at 24 hr after partial hepatectomy, the activity of both pentose phosphate pathway enzymes was in the same range as that of the sham-operated controls. In differentiation at the postnatal age of 5, 12, 23, and 32 days, hepatic transaldolase activities were 33, 44, 55, and 72%, respectively, of the activities observed in the 60-day-old, adult male rat. During the same period, transketolase activ-ties were 18, 21, 26, and 55% of the activities observed in liver of adult rat. The demonstration of increased transaldolase activity in hepatomas, irrespective of the degree of tumor malignancy, differentiation, or growth rate, suggests that the reprogramming of gene expression in malignant transformation is linked with an increase in the expression of this pentose phosphate pathway enzyme...
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PMID:Behavior of transaldolase (EC 2.2.1.2) and transketolase (EC 2.2.1.1) Activities in normal, neoplastic, differentiating, and regenerating liver. 1 80

L-Asparagine synthetase appears in serum approximately 7 days after the s.c. implantation of 1 X 10(5) cells of Leukemia 5178Y/AR (resistant to L-asparaginase) and increases in activity as the neoplasm grows and metastasizes. The principal source of the enzyme is the primary tumor. After intravranial inoculation of tumor, the rate of leakage of the enzyme is more pronounced than when the subcutaneous, intramuscular, or intraperitoneal routes are used. 1-(2-Chloroethyl)-3-cyclohexyl-1-nitrosourea (NSC 79037), a nitro-sourea effective in the palliation of L5178Y/AR, temporarily halts the influx of enzyme into the blood stream, as does surgical excision of the s.c. tumor nodules. Treatment of mice with L-asparaginase within 24 hr of inoculation of the tumor markedly augments both tumor growth and the rate of penetration of L-asparagine synthetase into the circulation. Several other L-asparagine synthetase into the circulation. Several other L-asparaginase-resistant tumors also were found to spill L-asparagine synthetase into the serum, but the correlation between this phenomenon and the specific activity of the enzyme in homogenates of the tumor was imperfect.
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PMID:L-Asparagine synthetase in serum as a marker for neoplasia. 1 81

A syndrome of male pseudohermaphroditism, cryptorchidism, and testicular neoplasia was diagnosed in 3 Miniature Schnauzers. The dogs had clinical signs of hyperestrogenism and were either unilateral or bilateral cryptorchids. At surgery, it was discovered that the dogs were male pseudohermaphrodites, having intra-abdominal testes containing Sertoli cell tumors and uteri that had undergone endometrial cystic hyperplasia.
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PMID:Male pseudohermaphroditism, cryptorchism, and Sertoli cell neoplasia in three miniature Schnauzers. 1 Feb 67

The kinetic and molecular properties of a phosphofructokinase derived from a transplantable rat thyroid tumor lacking regulatory control on the glycolytic pathway were studied. The properties of the near-purified enzyme (specific activity 140 units/mg) were compared with those of phosphofructokinase from normal rat thyroid (specific activity 134 units/mg). The electrophoretic mobilities and gel elution behavior of these two enzymes were almost similar. The thyroid tumor phosphofructokinase showed, however, a greater degree of size and/or shape heterogeneity in the presence of ATP than the normal thyroid enzyme, as determined by gel filtration and sucrose density gradient centrifugation. Kinetic studies below pH 7.4 showed a sigmoid response curve for both enzymes when the velocity was determined at 1 mM ATP with varying levels of fructose-6-P. The interaction coefficient, however, was 4.2 and 2.6 for normal and tumor thyroid phosphofructokinase, respectively. Ammonium sulfate decreased the cooperative interactions with the substrate fructose-6-P in both enzymes. The thyroid tumor enzyme, however, was less sensitive to the inhibition by ATP and by citrate. The reversal of citrate inhibition by cyclic 3':5'-adenosine monophosphate was also less effective with the thyroid tumor phosphofructokinase, while the protective effect of fructose-6-P was stronger. The difference in citrate inhibition between tumor and normal thyroid enzyme was not strongly affected by varying the MgCl2 concentration up to 10 mM. It is concluded that the complex allosteric regulation typical of the normal thyroid phosphofructokinase is still present in the enzyme isolated from the thyroid tumor tissue. The latter, however, is more loosely controlled by its physiological effectors, such as ATP, citrate, and cyclic AMP.
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PMID:Differences in phosphofructokinase regulation in normal and tumor rat thyroid cells. 1 Feb 94

Tumor incidence was studied in 1,2-dimethylhydrazine (DMH) injected male rats assigned at weaning to isoenergetic casein-sucorse deits containing 7.5%, 15%, or 22.5% protein with or without 2.5% urea. Twenty rats fed each diet were given weekly intraperitoneal injections of DMH (15 mg/kg body weight/week) for the first 24 weeks and 20 were given saline. Of 96 DMH-injected rats necropsied after 28 weeks, 88 were necropsied during the 32nd or final week of the experiment. Adenocarcinomas of the small and large intestine were larger and significantly more numberous in rats fed 15% and 22.5% dietary protein. Keratin producing papillomas of the sebaceous glands of the external ear were observed first at 21 weeks in DMH-injected rats fed 22.5% protein. These were subsequently observed in some rats from all DMH-treated groups. As time progressed, the ear tumors increased in size and number in all groups but the greatest incidence was in the group fed 22.5% protein. No tumors were observed in saline-injected rats. Urea feeding did not increase the number of tumors nor cause changes in pH, urease activity or ammonia concentration of contents of the colon or cecum, or blood cholesterol. As dietary protein increased, cecal ammonia concentrations rose while both colon and cecal pH dropped. Portal blood urea and cholesterol reose as dietary protein was increased. DMH-treated rats had significantly higher concentrations of colon and cecal ammonia and lower blood cholesterol. Altough the rats fed 7.5% protein gained significantly less weight during 0 to 6 weeks of feeding, their weight gain was significantly higher during 6 to 26 weeks. No tumors were found in rats necropsied at 16 weeks.
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PMID:Nitrogen intake and tumorigenesis in rats injected with 1,2-dimethylhydrazine. 1 Mar 59

Previous studies indicating the importance of catecholamine metabolism in neuroblastoma were briefly reviewed. Metabolic pathways were presented showing how the major urinary metabolites 3-methoxy-4-hydroxymandelic acid (VMA) and 3-methoxy-4-hydroxy-phenylacetic acid (HVA) are formed from norepinephrine and from dopamine plus 3,4-dihydroxyphenylalanine (DOPA), respectively. For 289 neuroblastoma patients at the time of diagnosis, the urinary excretion of VMA was significantly elevated in 75%, and HVA was elevated in 80%. Periodic assay of these metabolites during the course of the disease revealed that the excretion trends were of prognostic value with 80-90% reliability. By contrast, when the excretion in only the initial urine specimens was considered, the survival rate was the same for patients with normal, and with significantly elevated, excretion. Review of the results of tracer studies aimed at elucidating the in vivo metabolic origins of the urinary metabolites suggested that a) in neuroblastoma, the catecholamines were largely inactivated by intracellular metabolism in the tumor cells; b) there was excess production and excretion of the norepinephrine precursors, DOPA and dopamine; and c) in the tumors of most neuroblastoma patients, the initial enzyme in catecholamine synthesis, tyrosine hydroxylase, had an activity comparable with that in normal adrenal glands. The importance of the metabolism of catecholamines in patients with neuroblastoma was stressed: a) The excretion of elevated levels of urinary catecholamine metabolites were useful in diagnosis and in following the course of the disease, and b) study of the catecholamine metabolism in these patients permitted examination of possible relationships between the activity of the enzymes involved in catecholamine synthesis and the malignancy of this tumor.
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PMID:Catecholamine metabolism in neuroblastoma. 1 Apr 50

The activity of intracellular proteinases from Ehrlich ascites carcinoma bearing mice were compared with that from liver cells of normal mice and rats. The activity of intracellular proteinases was measured in the supernatant of Ehrlich ascites carcinoma cells homogenate. The activity of intracellular proteinases in normal mouse and normal rat liver were different at pH 3.5, pH 6.0 and pH 7.5. The activity in liver cells from Ehlrich ascites carcinoma bearing mouse at pH 3.5 was not significantly changed from normal mouse or rat liver cells, however at pH 6.0 and pH 7.5 the activity in the affected liver significantly decreased. The proteolytic activity in the supernatant of Ehrlich ascites tumor cell homogenate was 0.110 E750 mmu/mgN at pH 7.5, 0.154 E750 mmu/mgN at pH 3.5. The proteolytic activity at pH 6.0 was not detected in any experiment.
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PMID:Proteolytic activity in liver cells from mouse, rat, Ehrlich ascites carcinoma bearing mouse and in Ehrlich ascites carcinoma cells. 1 May 31


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