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Biomedical subjects

A Marcos

Publications and source records attributed to A Marcos.

104 records · Page 6Linked to original sources
PubMed1987

[Changes in the metabolism of muscle RNA in rats given a high protein diet].

The effect of a high protein diet (20% casein + D,L-methionine) administered to adult Wistar rats on some aspects of muscle RNA metabolism has been studied. Body weight increased in spite of lower intake. However, gastrocnemius muscle remained unmodified, although protein content increased. Total RNA decreased in the whole muscle although RNA/DNA ratio did not change. Protein synthesis capacity diminished 81% relative to controls in spite the fact that an excessive amount of available amino acids exists. RNA loss might depend on a high catabolism, since acid RNase activity increased over control values. Therefore, it may be concluded that a high protein diet leads to a lower protein synthesis capacity through an elevated RNA breakdown.

Animals↗
PubMed1986

[High protein diet in pregnancy. Effects on neonatal metabolism].

The effect of a high protein diet (20% casein + D,L-methionine) administered to Wistar rats during pregnancy on some aspects of cellular growth and RNA metabolism of progeny has been studied. Comparisons were made with well-nourished (10% casein + D,L-methionine) controls. Newborns individual weight, litter weight and number of newborns per litter were unmodified. However, neonate protein content dropped significantly when compared with controls. Both rate of DNA and number of nuclei were unchanged. Protein/DNA ratio (cellular size relative to protein) decreased, which might have led to an atrophy phenomenon, even if the newborn weight/number of nuclei ratio was not modified. Acid DNase activity rose, bringing about DNA breakdown. Total RNA content together with RNase activity fell in newborn from rats suffering high protein diet. Moreover, protein synthesis capacity (RNA/protein ratio) did not change. These results suggest that the administration of a high protein diet to pregnant rats lead to changes in newborn protein rate and nucleic acid turnover by modulating specific nuclease activity.

Animals↗
PubMed1986

[Additive effects of protein malnutrition and cortisol on plasma proteins and immunoglobulins of pregnant rats, and their offsprings].

This research work was carried out to study the effects of two immunosuppressive mechanisms: protein malnutrition and cortisol treatment on the feto-maternal unit. Therefore, plasma Ig G and Ig M levels were tested in pregnant rats submitted to a low protein diet (4%) and cortisol treatment (0.5 mg/100 g b.w.) during pregnancy and in their offspring. Nutritional status was evaluated by measuring ponderal parameters and plasma protein levels in rat dams and their neonates. Thus, a fall in ponderal parameters and in plasma protein levels was observed, both in rat dams suffering protein malnutrition as well as in their newborns. Cortisol treatment produced a decrease in the ponderal parameters of the control group, and an increase in plasma protein levels of the malnourished one, both in rat dams and in their neonates. Apparently, protein malnutrition might lead to a low functionality of B lymphocytes, caused by a decrease in Ig G and Ig M rates of malnourished rat dams. Ig M levels, however, increased in neonates as a consequence of possible concomitant infections. Cortisol treatment promoted humoral immune deficiency, since Ig G and Ig M levels decreased both in the control and in the malnourished pregnant rat groups. Nevertheless, cortisol administration seemed to increase susceptibility to infection in the newborns, especially in those born from malnourished rat dams.

Animals↗
PubMed1986

[Dietary protein level during pregnancy. Its influence on maternal-fetal exchange of substrates].

It is well known that the dietary protein level influences both the pregnancy process and development of the offspring. Therefore, a study was carried out to determine the effect that different protein percentages: 10%, 4% and 20% in diets administered to rats during pregnancy, had on food efficiency and on the substrates partition between rat dams and their neonates. Experimentation was thus carried out over a period of 21 days (pregnancy) and comparisons were made with well-nourished rats receiving 10% protein (controls) and between one and other group. Moreover, the effect on pregnancy was observed by comparing pregnant rats with non pregnant rats within each dietary situation. Food intake, weight parameters and food efficiency ratio were recorded in adult rats. Weight parameters were also evaluated in newborns. As results revealed, the highest the protein level in the diet, the highest the food efficiency ratio, both in the pregnant group and in the non pregnant group. Weight changes were determined in rat dams and their neonates, as a consequence of the different protein intakes. These also involved alterations in the substrates partition between the mothers and their offspring. Such findings might lead to the retention of substrates by the maternal tissues and, hence, to impairment of neonatal development.

Animal Nutritional Physiological Phenomena↗
PubMed1984

[Changes at the liver cell level in rats subjected to protein-calorie malnutrition].

The effect of a low protein-calorie diet (restricted diet) on cellular growth and on RNA metabolism in Wistar rat liver has been studied. Experimentation was carried out over 30 days and the comparisons were made against well-nourished group (10% protein, controls). Liver weight and hepatic proteins dropped significantly in malnourished rats. Both rate of DNA and number of nuclei were unchanged. However, protein/DNA and liver weight/number of nuclei ratios decreased, which led to an atrophy phenomenon. DNase specific activity however, was not modified. Liver RNA content together with RNase activity dropped in deficient rats. Protein synthesis capacity (RNA/protein) did not change. These results suggest that restricted diet leads to a lower hepatocyte size with a decreased rat of RNA turnover.

Animals↗
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↗
PubMed1981

Effect of protein deficiency on the lysosomal enzyme activities of the spleen and thymus of weanling rats.

The effect of a low protein (4%) diet on the activity of the hydrolytic enzymes ribonuclease, deoxyribonuclease, acid and alkaline phosphatases, beta-glucuronidase and lysozyme has been studied in the spleen and thymus of weanling Wistar rats. Experimentation was carried out over 20 and 30 days, and comparisons were made with well-nourished (12% protein) controls. Body weight decreased during the terminal period in protein-deficient animals (P less than 0.001). Spleen and thymus absolute net weights also dropped significantly (P less than 0.001). In terms of organ weight relative to body weight, there was a clear decrease in thymus compared with controls (P less than 0.001). Enzyme activities expressed per total organ fell significantly. Thus, in spleen at 20 days the decrease was maximum in ribonuclease activity (91.15%) and minimum in acid phosphatase activity (44.09%). Thymus decreases ranged from 83.60% activity in beta-glucuronidase and 93.56% in ribonuclease. At 30 days decreases were accentuated; the maximum value in spleen was 92.34% lysozyme and, in thymus, 97.09% acid phosphatase. A large increase in hydrolytic activity expressed per milligram of protein was registered, especially at 30 days. This increase reached a maximum of 78.08% beta-glucuronidase in thymus and a minimum of 56.1% alkaline phosphatase; acid phosphatase and ribonuclease activities were not modified. In spleen, however, acid phosphatase (34.00%), alkaline phosphatase (62.50%), deoxyribonuclease (39.25%), and beta-glucuronidase (36.01%) increased, but lysozyme and ribonuclease enzymes decreased. We concluded that a low protein diet increases catabolism in spleen and thymus through an enhancement of lysosomal hydrolase activities.

Acid Phosphatase↗
PubMedDate not supplied

Improvements in hepatic parenchymal transection for living related liver donor.

INTRODUCTION: To eliminate mortality and morbidity risk in living related liver donors, we developed a new surgical technique to resect hepatic parenchyma using an ultrasonic surgical aspirator in association with a monopolar floating ball cautery. METHODS: We performed 17 right hepatectomies and 2 left hepatectomies using this technique. We performed a retrospective analysis of perioperative mortality, length of hospitalization (LOS), blood transfused during surgery (IBT), intraoperative blood lost (IBL), biliary complications (BC), and aspartate aminotransferase (AST)/alanine aminotransferase (ALT) peak in the first postoperative week. This group of patients (Group A) was compared, using the analysis of variance (ANOVA) test (P < .05) with 2 different groups of 19 patients: Group B with liver neoplasms that had the same technique as Group A, and Group C wherein a crushing clamp technique was used. RESULTS: All of the analyzed variables showed significative statistical differences, especially between Group A and Group C (IBL, P < .000; IBT, P < .006; LOS, P < .028; BC, P < .000; AST peak, P < .041; and ALT peak, P < .023). DISCUSSION: The association of these 2 techniques seems to reduce the LOS, and the need for intraoperative blood transfusions. Moreover, the surgical complications (biliary leaks) and the postoperative parenchymal cytonecrosis seem to be less using this technique.

Adult↗
PubMedDate not supplied

Use of imaging for living donor liver transplantation.

Living donor liver transplantation is emerging as an alternative to cadaveric liver transplantation. The authors present multimodality images obtained in 44 cases of living donor liver transplantation. The images in this article were derived from the pre-, intra-, and postoperative imaging protocol for their institutional transplantation program. Preoperative magnetic resonance (MR) imaging in the donor allows detection of focal liver lesions and accurate determination of liver volume. The latter is crucial to ensure adequate postoperative liver function for donors and recipients. MR cholangiography depicts donor biliary anatomy. MR angiography and digital subtraction arteriography are performed to assess vascular anatomy. Intraoperative ultrasonography (US) helps determine the resection plane during donor hepatectomy. Postoperative MR imaging documents liver regrowth. MR imaging, US, and computed tomography help assess complications in donors and recipients.

Diagnostic Imaging↗
PubMedDate not supplied

[Effect of the diet on the nutritional status of ballerinas: immunologic markers].

UNLABELLED: Athletes have special nutritional needs that will vary with sex, age, body composition and most importantly by the type, intensity, frequency and duration of the physical exercise. However the diet of certain groups of athletes such as ballet dancers is inadequate due to overly restrictive habits as a consequence of their obsession with losing or maintaining a low body weight that reflects an aesthetic preference for thinness. Physical exercise implies energy expenditure and thus, an increase in the energy intake is required to avoid possible situations of malnutrition. Both a negative energy balance and physical exertion have been shown to induce immunological changes which have been implicated as a possible explanation for increased susceptibility to illness and infections. OBJECTIVE: To find out the influence of a restricted energy intake on the immune system of 14 ballet dancers (20-25 h/w) in comparison with a control sedentary group (n = 23) by evaluating dietetic, anthropometric and some immunological parameters. RESULTS: Ballet dancers consumed a hypocaloric diet (mean: 1555 kcal), the energy intake being significantly lower than in the control group. None of both groups showed a similar calorie profile to the recommended intake for Spanish population, especially fat percentage was higher than it should. Regarding weight, ideal body weight and BMI values, no significant differences were shown between both groups. However, all the skinfolds thickness and the sum of skinfolds were significantly lower in ballet dancers than in controls. Leukocytes, lymphocytes and all lymphocyte subset counts were lower in ballet dancers in comparison with controls. CONCLUSIONS: In view of these results, ballet dancers may suffer from an impaired nutritional status, determined by a depletion of anthropometric and immunological parameters. The nutritional requirements for this population should be increased in order to compensate their high-energy expenditure, avoid a negative energy balance and lessen the nutritional damage.

Adolescent↗
PubMedDate not supplied

[Feeding and assessment of nutritional status of spanish adolescents (AVENA study). Evaluation of risks and interventional proposal. I.Methodology].

BACKGROUND: Adolescence is a decisive period in human life due to the multiple physiological and psychological changes that take place. These changes will condition both nutritional requirements and eating/physical activity behavior. It has been demonstrated that these "adolescence" factors are of significant influence in health status during adult life. Due to its importance and adequate development the project has been granted by the Fondo de Investigación Sanitaria of the Institute of Health Carlos III. OBJECTIVE: To develop a methodology to evaluate the health and nutritional status of a representative population of Spanish adolescents. Specific attention is paid to three specific health problems: obesity, anorexia nervosa/bulimia, dislipidemia. METHODOLOGY: The following magnitudes will be studied: 1) dietary intake, food habits and nutrition knowledge; 2) daily physical activity and personal approach; 3) physical condition; 4) anthropometry and body composition; 5) hematobiochemical study: plasma lipid phenotypic and metabolic profile, blood cell counts; 6) genotipic profile of cardiovascular risk lipid factors; 7) immune function profile related to nutritional status; 8) psychological profile. CONCLUSION: This project includes the co-ordinate activity of five Spanish centers of five different cities (Granada, Madrid, Murcia, Santander, Zaragoza). Each center is specialized in a specific area and will be responsible for the corresponding part of the study. From the data obtained, we will elaborate a specific intervention program in order to improve nutrition and neutralize the risk for nutritional related problems in adolescence. By this, we will contribute to improve the health status of the Spanish population in the new millennium.

Adolescent↗
PubMedDate not supplied

[Contribution to the intake of macro and micro nutrients exerted by moderate beer consumption].

OBJECTIVE: Moderate beer consumption can be part of a healthy diet, like the Mediterranean diet. The aim of the present study was to analyse the contribution a moderate beer consumption makes to energy and nutrient intake in Spanish healthy adults. MATERIAL AND METHODS: As part of a larger intervention study, dietary intake was measured by means of a 7-day food dietary record in 24 men and 22 women (age 34.18 +/- 5.80 years) twice: during the last week of the 30 days of complete alcohol abstinence and during the last week of 30 days of moderate beer consumption. Energy and nutrient content of food was analysed by means of the GEA program, based on the Spanish food composition tables. RESULTS: In women, moderate beer consumption increased significantly (p < 0.05) mean vitamin B6 (1.24 +/- 0.32 to 1.47 +/- 0.34 mg), B12 (3.87 +/- 1.46 to 5.58 +/- 2.76 microg), A (614.45 +/- 224.75 to 788.3 +/- 486.1 microg), and folate (139.5 +/- 39.88 to 168.25 +/- 56.32 microg) intake, whereas there was a decrease in mean iodine intake (327.1 +/- 148.4 to 281.2 +/- 135.02 microg). In men, mean vitamin B2 (1.64 +/- 0.62 to 1.91 +/- 0.46 mg), B6 (1.54 +/- 0.63 to 1.80 +/- 0.37 mg), niacin (30.01 +/- 8.13 to 34.78 +/- 6.26 mg) and folate (153.23 +/- 68.70 to 192.32 +/- 46.73 mg) intake also increased significantly. Energy, macronutrient and mineral intake had non-significant oscillations. CONCLUSION: Moderate beer consumption can improve diet quality in regard to B vitamins in healthy adults.

Adult↗
PubMedDate not supplied

[Splenic abscess, a diagnostic and therapeutic problem].

Splenic abscess remains a rare entity, reserved for patients with predisposing factors or immunosuppressive conditions. In our 13 patients in which a splenic abscess was diagnosed pre- or intra-operatively, an average of 14 days past before the diagnosis was made. Main symptoms were fever, upper left abdominal pain, auscultatory left basal anomalies and splenomegaly. Culture from the spleen material included E. coli, Staphylococcus, Proteus, Salmonella and Streptococcus v. Although splenectomy has been considered the standard procedure for this pathology, we treated our last three patients by means of Computed Tomography Percutaneous Drainage (C.T.G.P.D.). There was no need for splenectomy after this procedure and there were no complications associated with the C. T. G. P. D.

Abscess↗