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G Sava

Publications and source records attributed to G Sava.

At least 91 records · Page 5Linked to original sources
PubMed1982

Metabolism and mechanism of the antileukemic action of isomeric aryldimethyltriazenes.

Mice bearing TLX5 lymphoma or P388 leukemia were treated with ortho, meta, and para isomers of the salts of (3,3-dimethyl-1-triazeno)benzoic acid. Survival time was markedly increased in mice given the para isomer; effects were less pronounced for the meta isomer and absent for the ortho isomer. The in vivo effects of the tested compounds did not correlate either with the propensity of the drugs to undergo oxidative N-demethylation and hydrolysis to diazonium cations or with in vitro cytotoxicity for TLX5 lymphoma cells. The para isomer did not reduce the number and viability of peritoneal TLX5 lymphoma cells after in vivo and in vitro treatment, whereas a dose-dependent reduction that can even result in the absence of clonogenic tumor cells occurred in the brains of the treated animals. These data indicate that the increased survival time of the tumor-bearing mice treated with the para isomer should not be ascribed to cytotoxic effects of the drug and might be attributed to inhibition of tumor cell dissemination in various organs of the host, as already observed for solid metastasizing tumors in mice.

Animals↗
PubMed1981

Selectivity of the antimetastatic and cytotoxic effects of 1-p-(3,3-dimethyl-1-triazeno)benzoic acid potassium salt (+/-)-1,2-di(3,5-dioxopiperazin-1-yl)propane, and cyclophosphamide in mice bearing Lewis lung carcinoma.

The effects of two selective antimetastatic agents, 1-p-(3,3-dimethyl-1-triazeno)benzoic acid potassium salt (DM-COOK), and (+/-)-1,2-di(3,5-dioxopiperazin-1-yl)propane, have been examined in comparison with those of a cytotoxic agent, cyclophosphamide, in mice bearing Lewis carcinoma. Cyclophosphamide at the two highest dosages causes a strictly related and pronounced inhibition (to less than 10%) of the weight of the s.c. tumor, spontaneous metastases, and lung colonies formed after i.v. injection of tumor cells (artificial metastases); this behavior is consistent with a purely cytotoxic mechanism. At the three dosages used, (+/-)-1,2-di(3,5-dioxopiperazin-1-yl)propane reduces the weight of spontaneous metastases to less than 3%. A dose-dependent reduction of artificial metastasis weight is also observed. At the highest dose, artificial metastasis weight is reduced to about 5%, and s.c. tumor mass is significantly lowered to 40%. These effects are consistent with the combined occurrence of cytotoxic and selective antimetastatic action, although the latter appears to be predominant. At the three dosages used, DM-COOK markedly depresses the weight and number of spontaneous metastases to about 10%, leaving the formation of artificial metastases unaffected and causing no significant effect on primary tumor growth. The effects of these agents on the fractional incorporation of [3H]thymidine in tumor cells further indicate that only DM-COOK is devoid of cytotoxic effects for pulmonary and s.c. tumors. In hosts pretreated with DM-COOK, no reduction in the formation either of spontaneous or of artificial metastases is observed. These data indicate that DM-COOK acts directly on tumor cells and that it presumably inhibits their release from the primary tumor into the bloodstream.

Animals↗
PubMed1980

Synthesis of 1-aryl-3-formyl-3-methyltriazenes, potential metabolites of 1-aryl-3,3-dimethyltriazenes.

Some para-substituted 1-aryl-3,3-dimethyltriazenes were oxidized with tert-butyl hydroperoxide in the presence of vanadium pentoxide as a catalyst. Under these conditions, the corresponding 1-aryl-3-formyl-3-methyltriazenes, 1-aryl-3-tert-butylperoxymethyl-3-methyltriazenes, and p-nitrobenzenes were obtained. The 1-aryl-3-formyl-3-methyltriazenes might play a role in the metabolic oxidation of the 1-aryl-3,3-dimethyltriazenes, which are active as mutagenic, carcinogenic, and antitumor agents.

Triazenes↗
PubMed1980

[Truncal vagotomy in the surgical management of bleeding duodenal ulcer. Report of 50 cases (author's transl)].

To control hemorrhage and eliminate the ulcerogenic mechanism, some surgeons have favored gastric resection and others have preferred the more conservative approach of a vagotomy. The analysis of our 50 cases has shown a high frequency of hemorrhage by arterial erosion. All the patients have been treated by transfixing the ulcer with a local suture, associated with a truncular vagotomy and a gastric drainage, the global mortality rate was 26%. The mortality rate in the group of patients with massive bleeding forcing emergency operation is 33%. No death was observed in the group of patients where bleeding was controlled firstly by non operative measures and operated on later. The patient's chances of survival are markedly improved in the group of younger patients. The analysis of literature have shown that the incidence of rebleeding is the same following vagotomy or partial gastrectomy. The post operative mortality rates after these two types of emergency operative procedures are also quite similar. In conclusion, direct ligation of the ulcer base in massive bleeding, coupled with vagotomy, seems to be the operation of choice.

Adult↗
PubMed1979

[Vasoactive intestinal peptide (VIP) in the Verner-Morrison syndrome (author's transl)].

An early diagnosis of the Verner-Morrison syndrome will greatly enhance the chances of curative resection. There is a striking need for a simple diagnostic test. A number of suggestions have been made for the presumed hormone mediator of this syndrome. Numerous reports have led to a wide acceptance that vasoactive intestinal peptide (VIP) is the responsible mediator for the pharmacologic actions of this peptide are similar to the physiological characteristics noted in the watery diarrhea syndrome. A raised plasma VIP concentration, on the other hand, would suggest the presence of a tumour. These observations argue for the radioimmunoassay measurement of plasma VIP in a patient with the watery diarrhea syndrome.

Adenoma, Islet Cell↗
PubMed1978

Antitumor action of rhodium (I) and iridium (I) complexes.

Several rhodium(I) and iridium(I) complexes displayed different degrees of antitumour activity when tested in mice bearing Ehrlich ascites carcinoma. Rhodium (I) and iridium (I) acetylacetonate derivatives caused a high percentage of cures. The rhodium (I) dimers were particularly interesting, since (bis(cycloocta-1,5-diene)micromicron' dichlorodirhodium(I) [RhCODCl]2) was highly effective, whereas its analogues, bis(bicyclo[2,2,1]hepta-2,5-diene)micromicron'-dichlorodirhodium(I) [RhNBDCl]2) and bis(1,5-hexadiene)micromicron' dichlorodirhodium(I) [RhEDCl]2) were virtually inactive. The absence of significant inhibition of DNA, RNA and protein syntheses in tumour cells found for [RhCODCl]2 at therapeutically active dosages, indicates that this substance has a different mechanism of action from that of cis-dichlorodiammine Pt(II) (cis-PDD). The amount of rhodium found in tumour cells after administration of active [RhCODCl]2 was higher than that for [RhEDCl]2, while the rhodium concentration in the ascitic fluid was much higher for [RhEDCl]2. A mechanism based on the chemical properties of the complexes is tentatively proposed for explaining these findings and selective toxicity for tumour cells.

Animals↗
PubMed1978

Operative injuries to the bile ducts. Report on 12 cases.

We have reported on a series of 12 operative injuries to the bile ducts. We estimate the frequency of these accidents at 0.2% during cholecystectomy and 0.4% after gastroduodenectomy. We stress the importance of systematic cholangiography during the operation to prevent unrecognized lesions. Immediate repair of these lesions by an end-to-end anastomosis appears to be the best technical method. When faced with a high mortality rate, often due to non-recognition of a lesion, we stress the importance of prevention to limit the risk of such accidents occurring and non-recognition of those that do occur.

Adult↗
PubMed1977

[Volvulus of the ascending colon. Apropos of 5 cases].

The authors report five cases of volvulus of the right side of the colon, including 3 with complications, which required segmental colonic resection. They recall the diagnostic and therapeutic problems, emphasising the interest of barium enema, the necessity of early diagnosis, the high level of mortality and the treatment of choice which is right hemicolectomy.

Adult↗