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T Teodosiu

Publications and source records attributed to T Teodosiu.

15 recordsLinked to original sources
PubMed1977

Effects of cobalt-60 gamma-irradiation in association with prostaglandin E1 treatment on the cyclic AMP levels of some radiosensitive tissues.

The amounts of cyclic AMP in brain, liver and intestinal mucosa have been measured in rats, at constant intervals, up to 18 days after whole-body exposure to either a unique moderate dose (500 rd) or a unique lethal dose (750 rd) of cobalt-60 gamma-radiation in association with a preliminary intraperitoneally treatment with prostaglandin E1 (5 microgram/100 g body weight/day) during five days. The amounts of tissular cyclic AMP in these two experimental groups were compared with those obtained from control groups identically irradiated or treated with prostaglandin E1. The effects of gamma-irradiation and prostaglandin E1 treatment on the cyclic AMP levels were found to be quite specific in these organs, suggesting that they contain different adenyl cyclase-cyclic AMP-phosphodiesterase systems: a cerebral system which is influenced by both gamma-radiation and prostaglandin E1, a hepatic system which is "radioresistant" and an intestinal system which is not influenced by prostaglandin E1. When associated with gamma-radiation, this prostaglandin is capable, on the one hand, to annul the "radioresistance" of the hepatic cyclic AMP system and, on the other hand, to annul the "radiosensitivity" of the intestinal cyclic AMP system.

Animals↗
PubMed1976

Endogenous biochemical factors affecting the efficiency of some radioprotective or radiosensitizing drugs: sulfhydryl groups and lipid peroxides.

The changes in the amounts of blood and tissular sulfhydryl groups and lipid peroxides were investigated in lethally gamma-irradiated rats treated with cystamine, AET (radioprotectors) or alpha-methyl-dopa (a radiosensitizer). The results of experiments revealed the following findings: 1. The ionizing radiation generally causes increases in the levels of tissular sulfhydryl groups and lipid peroxides (excepting the hepatic levels of these compounds). 2. AET and, especially, cystamine are able to reverse the radiation-induced changes in the tissular amounts of sulfhydryl groups and lipid peroxides; there are close relationships between this effect (including its intensity and extension) and the radioprotective action of these drugs. 3. In spite of its radiosensitizing action, alpha-methyl-dopa induces approximately similar changes in the tissular amounts of sulfhydryl groups and lipid peroxides, suggesting that biochemical processes other than an excessive yield of free radicals are also involved in radiosensitivity.

Animals↗
PubMed1976

Dynamics of the changes in the tissular levels of cyclic AMP after cobalt-60 gamma-irradiation.

The total amounts of cyclic AMP in liver, brain and intestinal mucosa have been measured in rats, at constant intervals, up to 18 days after whole body exposure to either a unique moderate dose (500 rd) or a unique lethal dose (750 rd) of cobalt-60 gamma-radiation. This radiation, even in a lethal dose, was found to induce no significant changes in the hepatic levels of cAMP. In contrast, an abrupt short-lasting increase in the levels of cAMP was observed in brain and intestinal mucosa after a 500-rd-irradiation, and a progressive long-lasting increase in its levels in the intestinal mucosa and, especially, in the brain was found after a 750-rd-irradiation. It is concluded that these organs contain different cAMP systems, which would explain, at least in part, their dissimilar responses to the ionizing rays.

Adenosine Triphosphate↗
PubMed1967

Monilethrix.

Explore the source record for details and available documents.

Adult↗
PubMedDate not supplied

Changes in the activities of blood and tissue adenosinetriphosphatase and lactate dehydrogenase after exposure to 60Co gamma-rays in association with some drug treatments.

Experiments in rats exposed to a moderate dose of 60Co gamma-radiation and treated with either cystamine, AET, complamin or alpha-methyldopa suggested that the efficiency of a radioprotective drug might be related to its ability to maintain low levels of ATP-ase activity in blood and tissues after irradiation.

Adenosine Triphosphatases↗
PubMedDate not supplied

Comparative study of the gamma-radiation-induced changes in the tissular levels of acyclic and cyclic adenosine phosphates.

Periodical measurement of total adenosine phosphates and cAMP in liver, intestinal mucosa and brain carried out in rats after irradiation with either 500 rads or 750 rads generally revealed high intratissular levels of these compounds, suggesting both a stimulated cellular synthesis and an abnormal redistribution in different tissues. The most interesting findings were those regarding the brain considering their close relationships with the clinical evolution of the animals and other previously described biochemical observations.

Adenosine Monophosphate↗
PubMedDate not supplied

Dynamics of the changes in the cerebral amounts of cyclic AMP and some prostaglandins during cobalt-60 gamma-radiation-induced brain edema.

The total amounts of cyclic AMP (cAMP), prostaglandin E1 (PGE1) and prostaglandin F2alpha (PGF2alpha) in cerebra have been measured in rats, at constant intervals, up to 18 days after whole body exposure to either a unique moderate dose (500 rads) or a unique lethal dose (750 rads) of cobalt-60 gamma-radiation. The experimental findings indicate that this radiation (i) results in an abrupt short-lasting increase in the amount of cerebral cAMP after a 500 rad-irradiation and a progressive long-lasting increase in its amount after a 750 rad-irradiation, and (ii) induces no change in the normally, existing correlation between cerebral PGE1 and cAMP, but affects deeply the normally existing correlation between cerebral PGF2alpha and cAMP. These biochemical alterations generally parallel the evolution of the radiation-induced brain edema.

Animals↗
PubMedDate not supplied

Adrenal function in early and metastatic breast cancer: dexamethasone suppression of plasma cortisol.

Plasma cortisol, 17-hydroxyprogesterone (17-OH-P), progesterone, FSH, LH and prolactin were determined by RIA, in 14 cancer patients without metastases aged between 40 and 74 years (6 cases of breast cancer: T123, N01, M0 and 8 with other forms of cancer). The cancer patients were investigated: (A) under basal conditions, (B) after three days' adrenal suppression by dexamethasone, 3 mg/day and (C) immediately after local radiation therapy (4500 rads). The basal mean hormonal values in these patients showed increased cortisol, decrease 17-OH-P and normal values of progesterone, FSH, LH and prolactin. Plasma cortisol was significantly reduced by adrenal suppression with a percentage reduction of 19.44 without differences between breast cancer patients and patients with other forms of cancer; adrenal suppression induced an increase of 17-OH-P only in male cancer patients. The only significant hormonal changes after local radiation therapy were increased plasma 17-OH-P values in both female and male cancer patients. A second group investigated in the present study consisted of 11 patients (6 castrated and 5 postmenopausal women) with metastatic breast cancer and presented increased plasma cortisol values, decreased 17-OH-P values, and a great scatter in the estrone values, some of them being very high.

Adrenal Glands↗