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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anaerobic culture conditions (95% argon/5% CO2) caused a slightly greater increase in total lipids of Ehrlich ascites tumor cells than a gas phase of 20% O2, 75% N2, 5% CO2. Whereas the rate of [U-14C]acetate incorporation into total lipids and lipid-subclasses rose markedly in the absence of oxygen, a drastic decrease of [U-14C]pyruvate and [1-14C]octanoate incorporation as well as a 30% reduction of 3H incorporation into lipids from tritiated water were observed under these conditions. Since profound changes in the metabolic state of cells cause alterations in the specific activity of the acetyl-CoA pool but do not alter the specific activity of intracellular water, this precursor is considered to be an adequate monitor for lipogenesis under aerobic and anaerobic culture conditions. Therefore, it is concluded that Ehrlich ascites tumor cells are not able to reoxidize NADH/NADPH in the absence of oxygen by a stimulation of biosynthesis of fatty acids as is discussed to be the case in normal cells. The slight increase in total lipids of anaerobically cultured cells seems to be the result of an imbalance between normal uptake and impaired utilization of lipids from serum-supplemented culture medium.
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PMID:Lipogenesis in Ehrlich ascites tumor cells under anaerobic culture conditions. 52 49

Comparison of a water-soluble (27-487) with a water-insoluble (VP-16-213) podophyllotoxin derivative in seven murine neoplasms revealed slight therapeutic superiortiy of VP-16-213 but also slightly greater toxicity when compared with 27-487. A strikingly good response of the Taper liver tumor to both compounds was observed, providing further incentive to the use of podophyllotoxin derivatives in human hepatomas.
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PMID:Comparison of a water-soluble and a water-insoluble podophyllotoxin derivative in murine neoplasms. 52 64

The renal reabsorption of water independent of solute is the result of the coordinated function of the collecting duct and the ascending limb of the loop of Henle. The unique juxtaposition of the ascending and descending portions of the loop of Henle and of the vasa recta permits the function of a counter-current multiplier system in which water is removed from the tubular lumen and reabsorbed into the circulation. The driving force for reabsorption is the osmotic gradient in the renal medulla which is dependent, in part, on chloride (followed by sodium) pumping from the thick ascending loop of Henle. Urea trapping is also thought to play an important role in the generation of a hypertonic medullary interstitium. Arginine vasopressin (AVP) acts by binding to receptors on the cell membrane and activating adenylate cyclase. This, inturn, results in the intracellular accumulation of cyclic adenosine monophosphate (AMP) which in some fashion abruptly increases the water permeability of the luminal membrane of cells in the collecting duct. As a consequence, water flows along an osmotic gradient out of the tubular lumen into the medullary interstitium. Diabetes insipidus is the clinical condition associated with either a deficiency of or a resistance to AVP. Central diabetes insipidus is due to diminished release of AVP following damage to either the neurosecretory nuclei or the pituitary stalk. Possible causes include idiopathic, familial, trauma, tumor, infection or vascular lesions. Patients present with polyuria, usually beginning over a period of a few days. The diagnosis is made by showing that urinary concentration is impaired after water restriction but that there is a good response to exogenous vasopressin therapy. Nephrogenic diabetes insipidus can be identified by a patient's lack of response to AVP. Nephrogenic diabetes insipidus is caused by a familial defect, although milder forms can be acquired as a result of various forms of renal disease. Central diabetes insipidus is eminently responsive to replacement therapy, particularly with dDAVP, a long lasting analogue of AVP. Nephrogenic diabetes insipidus is best treated with a combination of thiazide diuretics as well as a diet low in sodium and protein.
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PMID:The clinical physiology of water metabolism. Part II: Renal mechanisms for urinary concentration; diabetes insipidus. 54 67

We have experienced with 50 cases of parasellar tumors, four cases of which had persistent thirst, polydipsia, polyuria, and reversible temporary hyponatremia secondary to hypernatriuresis. The mechanism of the syndrome in these four cases could not be explained by either that of the syndrome of hypernatremia or of the so-called SIADH. We tentatively named this syndrome as "CEREBRAL POLYURIC HYPONATREMIA" and the criteria of this syndrome as as follows: 1) persistent thirst, polydipsia polyuria, 2) reversible temporary hyponatremia secondary to hypernatriuresis, 3) exception of the following items--administration of uretic drugs, renal and adrenal dysfunction, hyperglycemia, hyperlipemia, overadministration of water, and poor administration of NaCl. The mechanism of this syndrome is presumed as follows: 1) compression by a tumor or surgical attack to the anterior hypothalamus, 2) disturbance of the mechanism of ADH secret-on, 3) extrasecretion of natriuretic factor possibly produced in the anterior hypthalamus, and 4) preservation of the thirst center.
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PMID:[Cerebral polyuric hyponatremia--discussion of a new syndrome with disturbance of electrolyte balance of central origin (author's transl)]. 55 42

We have developed an experimental model of spinal cord compression in rats. Tumor injected anterior to the T-12 vertebral body grows through the intervertebral foramina to compress the cord and produces paraplegia in 3 to 4 weeks. Evidence for vasogenic edema in spinal cord compressed by tumor includes increased water content, leakage of horseradish peroxidase into gray matter, and histologic evidence of edema. The vascular supply to the cord overlying the tumor appears to be compromised. Both spinal cord edema and clinical symptoms are lessened by treating symptomatic animals with dexamethasone.
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PMID:Experimental spinal cord compression by epidural neoplasm. 55 45

A case of extracalvarial meningioma was reported. 75-year-old man was admitted to our department on November 11, 1974 because of a slowly growing tumor in the right frontoparietal area. The tumor was ovoid and 15x13 cm in size, protruding 5 cm above the skin level, and covered by the normal scalp. Neurological and electroencephalographic examination were negative. Spinal tap showed an opening pressure of 90 mm of water and clear CSF with 62 mg/dl of protein content. Plain roentgenogram and laminagram of the skull revealed both osteolytic and osteoblastic change in the outer and inner table of the skull just beneath the tumor. A right external carotid angiography disclosed a homogeneous extracalvarial tumor stain supplied by the superficial temporal artery and draining into the superficial temporal vein. A right carotid angiogram showed a 1 cm thick avacular area. The segmentally occluded superior sagittal sinus was displaced inward together with bridging collateral channels. Radiologically these picture corresponded to "intracranial non-globoid shape or avascular meningioma" discussed by Huckman et al. The tumor was well-circumscribed, encapsulated and loosely adherent to the periosteum and the skull except for a small portion through which the tumor was communicated with its intracranial part. Histological examination revealed that it was a typical endotheliomatous meningioma. This case should be allocated to the transitional or intermediate type between Lopez II and III type. In the schematical presentation (Fig. 6) we tried to readjust the rather confusing concept and classification of the extracalvarial meningioma.
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PMID:[Extracalvarial meningioma--report of a case (author's transl)]. 55 60

The intracellular distribution of Na+, K+, Cl- and water has been studied in the Ehrlich ascites tumor cell. Comparison of the ion and water contents of whole cells with those of cells exposed to La3+ and mechanical stress indicated that La3+ treatment results in selective damage to the cell membrane and permits evaluation of cytoplasmic and nuclear ion concentrations. The results show that Na+ is sequestered within the nucleus, while K+ and Cl- are more highly concentrated in the cell cytoplasm. Reduction of the [Na+] of the incubation medium by replacement with K+ results in reduced cytoplasmic [Na+], increased [Cl-] and no change in [K+]. Nuclear concentrations of these ions are virtually insensitive to the cation composition of the medium. Concomitant measurements of the membrane potential were made. The potential in control cells was -13.7 mV. Reduction of [Na+] in the medium caused significant depolarization. The measured potential is describable by the Cl- equilibrium potential and can be accounted for in terms of cation distributions and permeabilities. The energetic implications of the intracellular compartmentation of ions are discussed.
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PMID:Intracellular compartmentation of Na+, K+ and Cl- in the Ehrlich ascites tumor cell: correlation with the membrane potential. 56 Apr 90

Intravenous infusion of glucose in high dosage was given to 42 tumor patients, attaining a hyperglycemia of about 40 mg/100 ml over a period of 24 hours. This hyperglycemia is a part of the so-called "cancer-multistep-therapie". During the period of glucose-infusion a water-turnover of about 6,000 ml can be registered which is connected with a requirement of glucose of about 2,000 g. Only 1/3 of this amount is loosing by renal excretion, but 2/3 are metabolised to correspond with a glucose-uptake of 0,94 g and a glucosuria of 0,32 g per kg bodyweight and hour. Requirement of glucose and glucose uptake are in inverse proportion to the age of the patients and to the duration of hyperglycemia. Further a "glucose-potassium-equivalent" existed: about 10 mval potassium per 100 g infused glucose, whereas the netto uptake of potassium is 0,049 mval per g of metabolised glucose. Acid-base-equilibrium and red blood-picture did not show any relevant variations while typical deviations of some other parameters (cardiac-frequency, body-temperature), white blood-picture) are can be associated with the so-called "general adaptation syndrom". The findings are discussed in view of their general importance for the parenteral application of glucose.
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PMID:[Glucose and K+ balance during high-dosage intravenous glucose infusion]. 56 Oct 30

A solution of 2% succinic acid 2,2-dimethylhydrazide was given continuously in the drinking water of 6-week-old randomly bred albino mice for the remainder of their lives. The treatment gave rise to tumors of blood vessels, lungs, and kidneys. The tumor incidences in these tissues in the controls were 6, 18, and 0%, whereas in the treated groups the corresponding tumor incidences were 73, 73, and 5%. Light microscopic examination revealed typical angiomas and angiosarcomas of blood vessels, adenomas and adenocarcinomas of lungs, and adenomas of kidneys. The study thus demonstrates the tumorigenicity of the herbicide, succinic acid 2,2-dimethylhydrazide. Since the residues of this chemical occur in fruit, the human population is exposed to it. The environmental implication of this finding and the fact that the hydrazines as a class have tumorigenic properties are discussed.
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PMID:Induction of tumors in mice with the herbicide succinic acid 2,2-dimethylhydrazide. 56 52

N'-Acetyl-4-(hydroxymethyl)phenylhydrazine was administered as a 0.0625% solution in drinking water continuously for the life span of Swiss mice, from 6 weeks of age. Compared to that in untreated controls, in treated animals the lung tumor incidence rose from 15 to 34% in females and 22 to 48% in males, whereas the incidence of blood vessel tumors increased from 8 to 32% in females and from 5 to 30% in males. Histopathologically, the tumors were classified as adenomas and adenocarcinomas of the lungs and angiomas and angiosarcomas of the blood vessels. The commonly eaten mushroom Agaricus bisporus contains beta-N-[gamma-L(+)-glutamyl]-4-hydroxymethylphenylhydrazine, which under certain conditions yields 4-hydroxymethylphenylhydrazine and L-glutamic acid. Since 4-hydroxymethylphenylhydrazine is relatively unstable, its acetyl derivative was synthesized for this study. The possible environmental significance of the findings is discussed.
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PMID:Tumor induction with the N'-acetyl derivative of 4-hydroxymethyl-phenylhydrazine, a metabolite of agaritine of Agaricus bisporus. 56 87


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