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G Muzio

Publications and source records attributed to G Muzio.

44 records · Page 3Linked to original sources
PubMed1986

New data on kinetics of lipid peroxidation in experimental hepatomas and preneoplastic nodules.

Lipid peroxidation has been found decreased in several hepatomas. The decline has been shown already at the level of preneoplastic nodules obtained after DEN treatment of rats. A substantial exception is represented by the hepatoma cell line MH1C1, deriving from a slightly deviated Morris tumor. Most of the described experiments estimated lipid peroxidation levels in terms of malonaldehyde production by the thiobarbituric acid test. It is now clear that this test does not account for several other aldehydes produced during lipid peroxidation. We now investigated by high performance liquid chromatography (HPLC) the whole range of non-polar aldehydes produced by tumor homogenates and by preneoplastic nodules both in basal conditions and after stimulation with ADP-iron or ascorbate. It was reduced in the preneoplastic nodules as well as in the DEN-induced hepatoma. The susceptibility to the prooxidant effect of ADP-iron or ascorbate was strongly decreased in all hepatomas as well as in preneoplastic nodules. It has been recently published that hepatoma cells are more susceptible than normal liver to the toxic action of aldehydes. This was attributed at least in part to the decreased activity of aldehyde dehydrogenases, as well as to their different distribution in tumor cells. A deeper study on aldehyde metabolism in hepatomas has shown that alcohol dehydrogenase and NADPH-aldehyde reductase also are markedly decreased in Yoshida hepatoma cells and the MH1C1 cell line. However, glutathione transferase, that can use hydroxynonenal as a substrate, is strongly decreased in Yoshida hepatoma cells but not in MH1C1 cells.

Alcohol Dehydrogenase↗
PubMed1986

Glutathione synthesis in normal liver and in Yoshida AH-130 hepatoma.

The amount of reduced glutathione in transplantable hepatomas and in a primary DEN-induced hepatoma is lower than in normal liver. In all tumors examined, the glutathione decrease is not due to an increase of oxidized glutathione. In this paper the in vitro activities of two enzymes involved in glutathione synthesis, gamma-glutamylcysteine synthetase and glutathione synthetase, are studied in normal adult rat liver, in regenerating rat liver and in highly anaplastic Yoshida AH-130 hepatoma cells. The activity of these enzymes was determined in the postmicrosomal supernatant fraction as nmoles of [U-14C]-glutamate incorporated into product per mg of soluble protein. In Yoshida AH-130 hepatoma, the gamma-glutamylcysteine synthetase and glutathione synthetase activities are lower in respect to normal liver. This is in agreement with the low glutathione content observed in the hepatoma cells. On the other hand, in regenerating liver, there are minimal differences in comparison with normal liver.

Animals↗
PubMed1985

The effect of various aldehydes on the respiration of rat liver and hepatoma AH-130 cells.

Some aldehydes, produced during lipid peroxidation of liver lipids, are able to inhibit the respiration of mitochondria and of intact cells both in normal hepatocytes and in Yoshida hepatoma. In mitochondria, the respiratory stimulation produced by addition of ADP and dinitrophenol is decreased more in hepatoma than in normal liver. Two- to four-fold higher concentrations of aldehydes are needed to obtain the same degree of inhibition in normal liver mitochondria as in tumorous organs. The effect of aldehydes on intact cell respiration is absent or very low in hepatocytes, but it is consistently observed in hepatoma cells.

Aldehydes↗
PubMed1984

Functional alterations of the endoplasmic reticulum and the detoxification systems during diethyl-nitrosamine carcinogenesis in rat liver.

The mixed-function oxidase system shows a number of variations in the liver of diethyl-nitrosamine (DEN) treated rats. These include a decrease of the cytochrome P450 content and of the aminopyrine demethylase activity both in the hyperplastic nodules and in the hepatoma. Processes of detoxification, such as the glutathione system, show some modifications. These alterations are in accordance with the decrease of glutathione peroxidase and the increase of gamma-glutamyltranspeptidase during diethyl-nitrosamine carcinogenesis.

Aminopyrine N-Demethylase↗
PubMedDate not supplied

[Etiopathogenesis of hand syndactyly in the light of several experimental findings].

The limb developmental program is comprised of processes of cell multiplication and of cell determination, differentiation and morphogenesis. Many of these processes depend on cell-cell communications within tissues and between different tissue types. The Authors present a review of the more significant data about the etiology of the syndactylies of the hand, both in their physiopathogenic aspects and in their clinical typology. The peculiarity of these malformations is outlined, supported by literature data and personal experimental experiences.

Humans↗
PubMedDate not supplied

Conventional isolated hyperthermic antiblastic perfusion in the treatment of recurrent limb melanoma.

Hyperthermic Antiblastic Perfusion (HAP) is a widely used method for the treatment of recurrent limb melanoma. In terms of tumor response, locoregional control and survival HAP has led to better results than those achieved with any other treatment. The aim of this report is to analyze our own experience with HAP in locally advanced limb melanoma. Thirty-two patients were submitted to HAP. HAP lasted 60 minutes, with maximal local temperature of 40.5-42 degrees C using melphalan 10 mg/L limb volume as antiblastic agent. Twenty patients had in-transit metastases and 12 local recurrence. Regional nodes were involved in 12 patients. Systemic leakage monitored with 125I or 99Tc ranged between 5-30% (mean 14%). No operative mortality nor major complications occurred. Local toxicity scored Wieberdink grade I in 8 patients, grade II in 17, grade III in 6 and grade IV in 1 case. Response rate (UICC) in the 16 patients treated with unexcised lesions was 94% (56% complete responses). With a median follow-up of 29 months (2-126) 14 patients relapsed after a median time of 10 months, and 17 patients are currently disease free, 3 of these are being reexcised and 3 re-perfused. Actuarial 5 years survival was 64%, with 39% disease free to the first relapse. Our results are consistent with the literature indicating HAP as a safe procedure with a high evidence of clinical responses.

Adult↗