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We have previously described the synthesis of a cytotoxic polymeric conjugate of spermine (Poly-SPM) which is able to inhibit the transport of polyamines (spermine, spermidine, and putrescine) into normal and malignant cells. Recent studies examining the toxicity of Poly-SPM in parental and
The salts of the natural polyamines, protamine sulphate, clupeine sulphate, spermidine phosphate, putrescine dihydrochloride and spermine diphosphate, and of the synthetic poly-L-lysine hydrobromide (mol. wt 85 k) and poly-L-arginine hydrochloride (mol. wt 50 k) were tested for their effect on film
Examination of blood polyamines in 38 patients with brain tumor and 17 normal volunteers was carried out by columnar chromatography--cellulose acetate membrane electrophoresis. The upper limits of the normal values; M.+2S.D. of the blood polyamine concentrations in 17 normal volunteers, were less
Chick embryo fibroblasts and chorioallantoic membranes of chick embryos infected with oncogenic or nononcogenic viruses were analyzed for polyamines. Nononcogenic viruses (influenze, Newcastle disease, or vaccinia virus) had no effect on the polyamine content of chorioallantoic membranes.
Putrescine in determinable amounts is contained in the tumour tissue, in the liver tissue of normal animals it was not detected by the applied method. The spermidine content in the tumour is also considerably higher, it is 15.-3 times as high as that in the normal liver both per 1 g of fresh tissue
Polyamine uptake and metabolism were studied in cultures of normal and Rous sarcoma virus-transformed chick embryo fibroblasts. The uptake of radioactive putrescine and spermidine by the transformed cells was faster than that of the normal controls. The amount of radioactive putrescine and
DL-alpha-Hydrazino-delta-aminovaleric acid (DL-HAVA) is a potent and fairly specific inhibitor of ornithine decarboxylase (EC 4.1.1.17). Its effect on polyamine metabolism and cell proliferation was investigated in sarcoma-180, inoculated into the axillary region of mice. In the tumor tissues, the
Tertiary cultures of chick embryo fibroblasts infected and transformed by the wild-type Rous sarcoma virus, when actively growing at 35 degrees C, had higher putrescine levels than the respective uninfected cells. Transformed cells also had much higher specific activity of ornithine decarboxylase
The antitumor effect of dicyclohexylammonium sulfate (DCHA), a potent inhibitor of spermidine synthase, was tested on mice inoculated with Ehrlich ascites carcinoma, Ehrlich solid carcinoma and solid sarcoma-180. DCHA prolonged the survival time of mice bearing Ehrlich ascites carcinoma at doses of
Putrescine (PU), spermidine (SPD) and spermine (SPM) levels in blood serum of MC Sa 1828 P-bearing rats have been studied in relation to tumour weight and the histological picture. A statistically significant increase of PU and SPD was found in the course of tumour development. Decrease in the level
The oxidation of spermine in vitro by a mixture of polyamine oxidase and diamine oxidase from pig kidney gives rise to malondialdehyde via 3-aminopropanol as the intermediate. Conversely, with spermidine, under similar experimental conditions, no evidence could be obtained for malondialdehyde
Spermine, spermidine, putrescine and agmatine were examined for their cytotoxicity to mammalian cells in tissue culture. Spermine exhibited the highest cytotoxicity among them. It was followed by spermidine. Putrescine and agmatine showed little toxicity but rather acceleration of cell proliferation
The dose effects of continuous alpha-difluoromethylornithine (DFMO) infusion on red blood cell (RBC) polyamine levels, host toxicity and tumor growth were determined. Male rats with and without a transplantable methylcholanthrene-induced sarcoma received intravenously either 0.45% NaCl or DFMO at
The effects of cytostatic treatment on urinary polyamine excretion have been investigated in tumor-bearing (either Ehrlich carcinoma of S 180 sarcoma) and in tumor-free mice. The animals were exposed to single or multiple treatment with various doses of cyclophosphamide, 5-fluorouracil, or