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L R Bevilacqua

Publications and source records attributed to L R Bevilacqua.

9 recordsLinked to original sources

[Experimental study of fecal excretion of nitrogen in different nutritional conditions].

Fecal nitrogen excretion in different nutritional conditions were studied in 32 adult Wistar rats, casually distributed in four groups: group A (12), with normal control rats; group B (6), with subcutaneous impalnt of Walker-256 carcinosarcoma, at the beginning of the experiment; group C (8), with tumor implant eight days before the experiment beginning; group D (6), with standard skin wound in 15th day. The animals were fed with normoproteic diet (25% casein content). Nitrogen ingestion and urinary and fecal excretion were daily measured. Evaluation selected parameters were: nitrogen ingestion and urinary, fecal and total excretion; nitrogen fecal excretion/ingestion, nitrogen fecal excretion/urinary excretion and nitrogen fecal excretion/total excretion ratios; nitrogen urinary excretion/ingestion and nitrogen urinary excretion/total excretion ratios. Adequate statistical analysis was done with p < 0.05 critical limit value. It was observed that in normal animals nitrogen fecal excretion was equal to 5.7% ingestion value, 12.0% urinary excretion and 10.8% total excretion. In presence of malignant tumor, nitrogen fecal excretion was equal to 79% of normal animals value. In rats with skin wound in cicatrization nitrogen fecal excretion was 70.5% of normal animals value.

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Effect of diets with different protein levels on the growth of Walker 256 carcinosarcoma in rats.

1. The effect of different nutritional situations on the growth of experimental Walker 256 carcinosarcoma was investigated in rats. Fifty adult male Wistar rats were randomly assigned to three groups: group NN received standard chow throughout the experiment; group DD initially received an isocaloric protein-free diet, and some of the animals in this group (DN) were fed normal chow from the 37th to the 53rd day of the study. 2. On the 42nd day of the experiments all animals were inoculated subcutaneously in the flank with 2.5 to 3.0 x 10(5) viable Walker 256 carcinosarcoma cells and tumor growth and rat body weight were monitored daily thereafter. 3. Significantly greater tumor growth was detected in well-nourished (group NNT) as compared with malnourished animals (group DDT), but not in protein-depleted-refed (group DNT) animals, whose tumor growth was not significantly different from that of constantly malnourished (group DDT) rats. 4. Comparison of tumor weight and of the tumor weight/carcass weight (TW/CW) ratio showed no significant difference between malnourished and malnourished/refed animals, whereas well-nourished animals showed higher tumor weight and TW/CW ratios. 5. TW/CW curves for malnourished rats were parallel to those for malnourished/refed rats. TW/CW curves for constantly malnourished rats differed from those for well-nourished rats during the first observation period but there was no difference during the second week of tumor growth. 6. Although the protein-free diet inhibited tumor growth and refeeding enhanced it, carcass weight increased at the same rate, and therefore no change was observed in the TW/CW ratio.(ABSTRACT TRUNCATED AT 250 WORDS)

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[Body composition in various nutritional conditions. Experimental study].

Body composition parameters were studied in different nutritional conditions in Wistar rats with experimental cancer. Results were submitted to statistical analysis. Under a hyperlipidic diet, fat increased in control rats and decreased in animals with tumor; sodium increase and potassium decrease was verified in rats with tumor. The NA/K ratio increased in both groups and the N/K ratio increased in rats with tumor under standard diet, but decreased in rats with tumor under hyperlipidic diet. Fat decreased in the animals with tumor under an aproteic diet, but sodium increased. Potassium increased in undernourished animals of both groups. The Na/K ratio increased in rats with tumor. A comparison was made according to two different standards: "fresh body weight" and "fat-free body mass". The parameters analysed showed no significant differences in body composition.

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[Body composition changes in cancer: an experimental study].

With the aim to study body composition changes in tumor bearing rats submitted to different nutritional conditions, Wistar rats were separated in three diet groups: regular chow, aproteic diet and regular chow after three weeks of aproteic diet. Afterwards the animals were divided in two subgroups: Waler 256 carcinossarcoma bearing rats and tumor free controls. After the sacrifice body composition measurements by the carcass analysis method were performed. Tumor bearing rats presented significant waste of total body fat, body cell mass and increase of Na/K ratio without relation to the nutritional regimen. From this data we conclude that Walker 256 carcinosarcoma causes protein caloric malnutrition even in already depleted rats. After adequate refeeding, body composition rebuilding was obtained in tumor bearing malnourished rats.

Adipose Tissue↗

An experimental study of the impact of cancer on nitrogen metabolism and wound healing.

In Wistar rats bearing a Walker-256 carcinoma flank tumor, a standard skin wound was inflicted on the backs of the animals. Nitrogen intake and nitrogen balance measures were obtained. The standard wound did not promote tumor growth. Wound contraction in tumor-bearing animals was not different from that in tumor-free animals. Tumor-bearing rats had anorexia, lower nitrogen intake and a tendency to lower their nitrogen balance. These findings suggest that both cancer and wound healing are privileged metabolic events, having as a consequence sacrifice of the host.

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[Influences of antitumoral chemotherapy on body composition and nitrogen balance: experimental study].

An experimental study was carried out with the purpose to examine the 4-epidoxorubicine (4-EPI) action on malignant tumor development and its repercussion on nutritional conditions of the host. Cancer and chemotherapy can generate malnutrition. In order to study the nutritional repercussions, 48 host Wistar rats were divided into 5 groups: Group C: 12 control rats; Group T: 5 rats bearing Walker-256 carcinosarcoma; Group TE: 11 rats given 4-epidoxorubicine (4-EPI) EV simultaneously with tumor implantation; Group T6E: 8 rats given 4-EPI 6 days after the tumor implantation; Group E: 11 rats given only 4-EPI. Tumor and carcass weight and nitrogen balance (by measuring total nitrogen ingested and excreted) were determined daily; the animals were sacrificed on the 20th day of the experiment and material was collected for determination of body composition parameters. A variance analysis was made and the differences were considered to be significative at p less than 0.05. A loss of food during a period following the 4-EPI injection was reflected by carcass weight loss. The accumulated nitrogen incorporation was lower in Groups TE and T6E in the periods of 0-5 days, 0-14 days, and 0-20 days. As for body composition it was verified that free fat solids and total body fat were reduced in Groups T ant T6E when compared to group C. However, 20 days after the use of 4-EPI there were no significative changes in the body composition. In rats bearing Walker-256-carcinosarcoma 4-EPI was effective.(ABSTRACT TRUNCATED AT 250 WORDS)

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