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Biomedical subjects

G Varela

Publications and source records attributed to G Varela.

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

[Changes in hydrolytic lysosomal enzymes of liver associated with protein and protein-calorie malnutrition].

The effect of a low protein (1%) diet (protein-deficient diet) and a low protein-calorie diet (restricted diet) on the activity of the hydrolytic enzymes acid ribonuclease, acid deoxiribonuclease, acid and alkaline phosphatases and beta-glucuronidase has been studied in the liver of Wistar rts. Experimentation was carried out over 30 days and then comparisons were made against well-nourished (10% protein, controls), and one another. Body weight of deficient animals decreased in deficient animals, especially in protein-deficient rats. Liver weight also dropped significantly in malnourished rats. In terms of organ weight relative to body weight, there was a clear increase of protein-deficient rats, compared with controls. Enzyme activities expressed per total organ fell significantly in deficient rats compared with controls, but alkaline phosphatase activity increased. A large increase in hydrolytic activity expressed per mg of protein in beta-glucuronidase and alkaline phosphatase values was registered in protein-deficient and restricted rats. Also, acid ribonuclease activity increased in deficient-protein animals, but it fell in protein-calorie deficient animals compared with controls. However, acid deoxiribunuclease and acid phosphatase activities were not modified. We therefore concluded that protein-deficient and restricted diets increase catabolism in liver through a modulation of lysosomal hydrolase activities.

Animals↗
PubMed1982

Vitamin status of the Spanish population.

The Recommended Nutrient Intakes (R.I.) of all the nutrients are studied and fixed for our census (1980), according to the age, sex and activity. Comparative studies are also carried out through Balance Sheets and Nutrition survey of vitamins consumption. In our country, as in others, we have not enough information about clinical or subclinical deficiencies, neither about loss due to cooking processes, that is why the data obtained from the consumption of nutrient, must be relativized in order to consider the nutritional status of the population. The study is carried out with data of the years 1973, first data sufficiently solvent, and 1974 and 1979 period of important economic crisis which repercussion in nutrition can be interesting. The incidence on the consumption of the touristic population has also been considered. Our diet is at the same level than in the other european countries, with an excess of energetic consumption (40% higher of the R.I.) and normal caloric contribution between the different macronutrients. The average consumptions of vitamins are satisfactory, except for the riboflavin, dangerously situated near the R.I. levels which could reflect problems of deficiency in wide groups of population.

Adolescent↗
PubMed1982

[Rapid visualization and separation of serum lipoproteins of the rat by ultracentrifugation in saline density gradients].

A method is presented for the visualization and location of lipoprotein bands in density gradient ultracentrifugation. A 3 hour spin results in a good separation of the major rat serum lipoprotein classes: very low, low and high density lipoproteins, by using small centrifuge tubes and highspeed rotors. In addition, the concentration of cholesterol, triglyceride, phospholipid and protein in the lipoprotein fractions obtained by this technique was also determined.

Animals↗
PubMed1981

Effect of intestinal resection in dogs on different digestive parameters.

Some aspects of the digestive secretions in intact dogs (Control group) and the same dogs after resections of either 50 or 80% of the small intestine starting from the ileocaecal valve have been studied. In all of the animals the duodenal content flow, duodenal content pH, bile salts and amylase production have been determined; under fasting conditions, response to food (4% fat) and response to cholecystokinin-pancreozymin (CCK-PZ) injection (2 i.u./kg). Our results showed a decrease of pH and amylase production in resected animals, but duodenal content flow and bile salt production were not affected. The increase in duodenal content flow in response to feeding was delayed at onset in resected dogs. The pH and bile salts production were unchanged in response to food and to CCK-PZ injection in all animals, but amylase production decreased in response to food and particularly to CCK-PZ administration in resected animals.

Amylases↗
PubMed1981

[Effect of lindane on protein nutritive utilization in trout (Salmo gairdneri) (author's transl)].

Rainbow trout weighing 100 + 10 g were fed three diets of different proteic content (67.6%, 53.2% and 36.1%) and exposed to 0.01 and 0.001 ppm of Lindane in water during 21 days. The parameters calculated were: Protein Productive Value (PPV), Conversion Index (CI) and Protein Efficiency Ratio (PER). The PPV parameter increased with a diet proteic level decrease, at control and at Lindane treated groups. Minimum protein utilization corresponds to 67.6% proteic content diet and 0.01 ppm Lindane, while maximum, to 36.1% proteic content and Lindane 0.001 ppm. The CI and PER parameters were markedly different in groups on extreme diets (67.6% and 36.1%) with higher contamination level (0.01 ppm) from all the others. The experimental parameters were not practically affected by the presence or absence of Lindane in groups on diets of medium proteic content.

Animals↗
PubMed1981

[Cortisol influence on some typical parameters of protein malnutrition in rats (author's transl)].

A daily v.s. dose of cortisol administered to rats, induces certain metabolic modifications, which after using the "pair-fed" system have been proven to be at least partially independent of the ingesta decrease originated by cortisol. Both cortisol treatment and experimental proteic malnutrition, originate a decrease in corporal weight, a lessening of the gamma-globulins plasmatic fraction, and an elimination increase in total nitrogen, protein, creatine and creatinine in urine. Cortisol treatment determines an increase in blood red cells number, as well as an increase in total serum proteins, especially albumin, without provoking a lessening in the beta-globulins fraction, as happens in cases of proteic malnutrition.

Animals↗
PubMed1980

[Repercussions of prolonged ingestion of dieldrin on digestibility of nutrients and nitrogen balance in the quail].

The presence of organochlorated pesticides in foods intended for animal and human consumption is on one hand a real fact and on the other hand, it is known that they could alter some enzymes activities and, consequently, modify, at a larger or lesser extent, the metabolic pathways where they are implicated. According to this, it seemed interesting to study the influence of one of such molecules, dieldrin, on nutrients utilization. The work was carried out on adult quails (Coturnix coturnix japonica) of both sexes; 20 ppm, were mixed in their diets, during a period of 48 days. Dieldrin does not affect food intake in both sexes, but produces a significant weight decrease in the males. Nutritive utilization of protein, judged by digestibility coefficient and nitrogen balance do not suffered any alterations. Furthermore, dieldrin does not affect carbohydrate utilization (nitrogen free extract) and raw fiber. On the contary, fat digestibility decreased in pesticide treated males and was not altered in females and this effect dependend upon the exposition time to the contaminant.

Administration, Oral↗
PubMed1980

[Intestinal resections in rat: influence on protein absorption (author's transl)].

The effect of resections of 50% and 80% of small intestine, starting from the ileocecal valve on the nutritive utilization of protein, has been studied in rats. As a result of the resections, in the second week after the operation, the intake and weight of the animals decreased in both kinds of resections. The biggest decrease occurred in rats with 80% resection, while the loss of nitrogen in the faeces was greatly increased and, as a result, the digestibility coefficient was significantly reduced. The resected animals tended to recover gradually, but it was hardly noticeable at six and nine weeks after the operation. However, after three months, the recovery, although not total, was quite obvious, and the recovery rate was greater in the rats with 50% than in those with 80% resection.

Animals↗
PubMed1980

[Absorption of calcium by growing goats: effect of oxalates].

The influence of sodium oxalate and calcium oxalate upon calcium digestibility was studied in growing goats. Furthermore, and in the same animals, calcium absorption efficiency was estimated after performing duodenal fistula which allowed us to introduce calcium chloride or calcium oxalate and sodium oxalate, in order to avoid ruminal bacteria action upon the forementioned compounds. Finally, calcium absorption of an isolated intestine loop was studied in conscious goats with a Crocker Markowitz fistula, in the presence or absence of oxalate. The addition of sodium oxalate to the diet did not significantly decrease calcium absorption; but when calcium was given as oxalate, absorption was considerably lower. When calcium was introduced as calcium chloride through duodenal fistula, absorption was the same as when the substance was given in the diet. Calcium absorption drastically decreased when sodium oxalate was introduced directly into the duodenum, this fact is confirmed when calcium absorption is estimated in a jejunal loop, which shows that the differences found in relation to the effect of dietary sodium oxalate or directly introduced in duodenum are due to the substance destruction by ruminal bacteria.

Absorption↗
PubMed1979

[The age as a factor on the nutritive utilization of protein by rainbow trout (author's transl)].

Nutritive utilization of protein was studied in three age weight rainbow trout (Salmo gairdnerii) groups fed on a 37.5% casein-protein diet. As to digestive efficiency age was found to have no influence on the apparent and true digestibility coefficient for protein. On the other hand Biological Value, Net Protein Utilization and Protein Productive Value decreased with age-weight increases, the results being significantly correlated (P less than 0.001) between these parameters and the age-weight of the animals. Relative intake, weight increment and Protein Efficiency Ratio also decreased with age-weight increases.

Age Factors↗
PubMed1978

Dieldrin, Ca and P balance, and characteristics of the egg in the quail (Coturnix coturnix japonica).

A study was made of the Ca and P balance, Ca and P content in the femur, physical characteristics of the egg, mineral structure of the shell, and the number of eggs in quails treated with dieldrin (20 mg/kg of diet) for 48 days. The diet contained 3.24% Ca and 0.72% P. The Ca and P balance, the bone contents of Ca and P and the calcemia in the males were not changed by the pesticide. In the females, the pesticide decreased the amount of excreted Ca and Ca in the egg, for which reason the coefficient of nutritive utilization (CNU), the coefficient of corporal retention (CCR), and the Ca level in the femur were greater in treated laying quails. The calcemia remained stable, and the balance of P was not significantly modified by the dieldrin. The study of weight, size, and strength of the egg did not reveal any influence of the dieldrin, and egg production fluctuated throughout the test period.

Animals↗