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J Llopis

Publications and source records attributed to J Llopis.

At least 73 records · Page 4Linked to original sources
PubMed1990

[Evaluation of the nutritional status in a population of Andalusian schoolchildren].

The nutritional status of a population of school children was assessed with anthropometric data and information on nutrient intake. The three groups of subjects, all from the area around Vélez Málaga (Málaga-Spain), were aged 6-7, 10-12 and 13-15 years. The data revealed no significant departures from normal anthropometric patterns with the exception of triceps skin fold thickness, which was lower for both sexes in all groups than the normal figure established for these groups in the spanish population. Although no serious imbalances were recorded in nutrient intake, fat intake was higher than the recommended levels for spanish children's, while carbohydrate, fiber, calcium, magnesium, iron and zinc intake was lower in all groups, and vit. B2 intake was lower in the 10-12 years old group.

Adolescent↗
PubMed1989

Study of the redox properties of naphthazarin (5,8-dihydroxy-1,4-naphthoquinone) and its glutathionyl conjugate in biological reactions: one- and two-electron enzymatic reduction.

Naphthazarin (5,8-dihydroxy-1,4-naphthoquinone), the basic unit of several tetracyclic antitumor antibiotics, and its glutathione conjugate were reduced by the one- and two-electron transfer flavoproteins NADPH-cytochrome P450 reductase and DT-diaphorase to their semi- and hydroquinone forms, respectively. Kinetic studies performed on purified DT-diaphorase showed the following results: KNADPHm = 68 microM, KQuinonem = 0.92 microM, and Vmax 1300 nmol X min-1 X microgram enzyme-1. Similar studies performed on purified NADPH-cytochrome P450 reductase indicated a lower KNADPHm (10.5 microM) and higher KQuinonem (2.3 microM). The Vmax values were 20-fold lower (46 nmol X min-1 X micrograms enzyme-1) than those observed with DT-diaphorase. DT-diaphorase reduced the naphthazarin-glutathione conjugate with an efficiency 5-fold lower than that observed with the parent quinone. The nucleophilic addition of GSH to naphthazarin proceeded with GSH consumption at rates slower than those observed with 1,4-naphthoquinone and its monohydroxy derivative, 5-hydroxy-1,4-naphthoquinone. The initial rate of GSH consumption during these reactions did not vary whether the assay was carried out under anaerobic or aerobic conditions. Autoxidation accompanied the DT-diaphorase and NADPH-cytochrome P450 reductase catalysis of naphthazarin and its glutathionyl adduct as well as the 1,4-reductive addition of GSH to naphthazarin. Superoxide dismutase at catalytic concentrations (nM range) enhanced slightly (1.1- to 1.6-fold) the autoxidation following the enzymatic catalysis of naphthazarin. Autoxidation during the GSH reductive addition to 1,4-naphthoquinones decreased with increasing number of -OH substituents, 1,4-naphthoquinone greater than 5-hydroxy-1,4-naphthoquinone greater than 5,8-dihydroxy-1,4-naphthoquinone, thus revealing that the contribution of redox transitions other than autoxidation, e.g., cross-oxidation, to the decay of the primary product of nucleophilic addition increases with increasing number of -OH substituents. Superoxide dismutase enhanced substantially the autoxidation of glutathionyl-naphthohydroquinone adducts, thereby affecting only slightly the total GSH consumed and GSSG formed during the reaction. The present results are discussed in terms of the relative contribution of one- and two-electron transfer flavoproteins to the bioreductive activation of naphthazarin and its glutathionyl conjugate as well as the importance of autoxidation reactions in the mechanism(s) of quinone cytotoxicity.

Animals↗
PubMed1989

Glutathione depletion by hyperphagia-induced obesity.

Reduced glutathione (GSH) levels in freeze-clamped livers of rats and mice in which hyperphagia is induced by cafeteria diet are 45% lower than in controls. Freshly isolated hepatocytes from mice fed cafeteria diet show a 45% decrease in GSH concentration and a 54% decrease in oxidized glutathione (GSSG) concentration when compared with controls. The rate of GSH synthesis in isolated hepatocytes from control mice is significantly higher than in those from mice fed cafeteria diet. Oral GSH is effective to prevent the decrease in hepatic GSH levels found in cafeteria fed mice.

Animals↗
PubMed1989

Influence of hydrocortisone acetate administered to the lactating rat on lipid composition of the milk and serum lipid levels in dams and pups.

The influence of i.m. administration of hydrocortisone acetate to the mother (doses of 0.4, 0.8 or 2 mg/100 g body weight/day) during the first 15 days of lactation on milk composition in fatty acids mother and pups serum levels of lipids and their effect on pups' growth is studied. Serum levels of cholesterol and triglycerides in mothers increase at any of the experimental doses. Daily injections of 2 mg/100 g bw to the mother cause an increase in the percentage of C16 as well as in the level of fatty acids derived from linoleic and linolenic acids while reducing the percentage of C18:1. The treatment brings about a higher level in total lipids in the milk which is proportional to the dose. Doses of 0.4 and 0.8 mg increase the percentage of C8 and C10, while the dose of 2 mg enhances the % of C16. A fall in the uptake of linoleic acid by the mammary gland is observed when using any of the experimental doses. No change is observed either in the weight of pups or in serum cholesterol levels while triglyceride level is increased by the effect of treatment. The higher dose increases the level of linolenic acid and some of its derivates.

Animals↗
PubMed1989

Nutritional availability of magnesium and calcium in magnesium-supplemented diets.

The nutritive utilization of magnesium and calcium was studied using two different formulations of Mg: MgCO3 and an organic dietary Mg preparation. The influence of supplementation with the latter was also studied. The dietary organic magnesium did not modify food intake, which remained adequate in all animals used in the present experiments. Magnesium in both inorganic compound and organic preparation form was well absorbed; furthermore, absorption levels of the latter remained quite stable throughout the different experimental periods. Mg balance in both muscle and femur was similar in all groups studied. Digestive utilization of Ca and Ca content in the longissimus dorsi were higher in animals fed the organic Mg preparation while Ca levels in blood and femur were not affected.

Animals↗
PubMed1987

Influence of hydrocortisone acetate on the magnesium metabolism during pregnancy in rats.

The influence of hydrocortisone acetate i.m. administered (4 mg/100 g of body weight and day) to pregnant rats, on magnesium nutritive utilization and bone magnesium content in the mothers and its possible repercussions on newborn Mg content are studied. Hydrocortisone acetate treatment significantly reduces Mg content in the litters, which can be explained on the basis of a significant decrease in both the magnesium absorption and retention by the hormone-treated mothers. The mobilization of femoral magnesium and the increase in the urinary excretion of the cation provoke a reduction in magnesium retention in the treated mothers.

Animals↗
PubMed1987

Influence of hydrocortison acetate on the evolution of the nutritive utilization of calcium and phosphorus and their contents on the longissimus dorsi muscle during gestation in the rat.

The evolution of the nutritive utilization and plasma and muscular content of calcium and phosphorus in rats is studied, as well as the influence that hydrocortisone acetate has (4 mg/100 g weight and day), on them. In pregnant rats injected with saline solution, the retention of calcium is higher on the days 15-18 as a consequence of the increase on the net absorption of the cation. The balance of phosphorus reaches its maximum hight on days 18-21 of gestation, due to the decrease of the urinary excretion during these days. The administration of hydrocortisone acetate to pregnant rats originate a decrease of the net absorption and an increase of the urinary excretion of calcium and phosphorus, which leads to significantly lower balances than those of animals injected with saline solution. The hormone maintains the animals in a negative balance of phosphorus until day 18 of gestation. Besides, it impedes the high retention of calcium which is found with the control pregnant rats on days 15-18. In general, the content in calcium and phosphorus by gram of dry matter of Longissimus dorsi muscle is not modified during gestation. From day 9 of the treatment with hydrocortisone acetate a significant decrease of calcium and phosphorus of the muscle is observed, that in calcium is the more marked the more the treatment is prolonged. This effect seems to be due to the catabolic action of the hormone.

Animals↗
PubMed1987

Nutritive utilization of Ca and Mg in Mg-deficient rats: a recovery study.

Recovery from Mg deficiency was studied in adult Wistar rats fed a semisynthetic diet containing 0.04% Mg in the form of magnesium carbonate. Daily administration of a diet containing recommended levels of calcium carbonate to Mg-deficient rats led to the recovery, within the first seven days of treatment, of normal values in most of the parameters studied: gain in weight/day, and Mg retention and content in the Longissimus dorsi muscle and femur. Mg levels in whole blood, however, did not fully recovery until the second week of treatment. Net Ca absorption (ADC) and balance were significantly higher in Mg-deficient rats than in controls and remained elevated although to a lesser extent in the femur. Longissimus dorsi muscle, blood and plasma were unchanged by Mg deficiency.

Animals↗
PubMed1986

Magnesium utilization during gestation in the rat and effect of hydrocortisone on it.

The changes of magnesium utilization during pregnancy in rat and the influence of hydrocortisone acetate on it was studied. In the late days of gestation the Mg balance and magnesium content of bone increased significantly. This may be due to a greater requirement at this stage and to bone acting as a store for this cation. Hydrocortisone acetate at a dose of 4 mg/100 g body weight/day decreased the magnesium balance but did not modify the bone content of this mineral. The hormone had a catabolic effect on Longissimus dorsi muscle, producing a loss in magnesium. The effect is directly proportional to the duration of treatment.

Animals↗
PubMed1985

Influence of gestation and hydrocortisone-acetate treatment on the nutritive utilization of protein.

The effect of pregnancy and of cortisol on the digestive and metabolic utilization of protein in Wistar rats was studied. The cortisol is i.m. administered during 21 days in a pharmacological dose (4 mg/100 g weight per day) to female Wistar rats. Pregnancy is observed to increase and cortisol to decrease significantly the food intake (g dry matter/rat per day); the intake of nitrogen follows the same pattern. Pregnancy significantly increases the weight of both groups: pregnant rats as comparison to non-pregnant rats saline injected and pregnant rats cortisol-treated in relation to the animals pregnant but not hormone-treated. The increase being greater in the last 5 days of pregnancy. Cortisol in the pregnant and non pregnant rats considerably reduces the weight. The protein absorption is unaltered by pregnancy but is diminished by the effect of cortisol. Pregnancy increases the balance of nitrogen in both sets of rats; the increase being significantly greater in the last period of pregnancy. When administered to non pregnant rats, cortisol produces a negative balance of nitrogen. The protein of good quality (casein + 5% DL-methionine at a level of 12%) partially equalizes the negative effect of cortisol in spite of the long treatment and high doses used.

Animals↗
PubMed1983

Effect of cortisol on some nutritional and biochemical parameters in pregnant rats and their foetuses.

The influence of hydrocortisone acetate treatment (4 mg/100 g body weight i.m. and daily injected) was studied in pregnant rats and their litters. The parameters controlled were: food intake, body weight and body nitrogen, and liver enzimatic activity of PEPCK, in the mothers and number of foetus, weight, body nitrogen content and liver PEPCK activity in the litter. The hormonal treatment induces a significant reduction of food intake and weight of the mothers. In the same way the total body nitrogen content, is reduced but not its concentration (body nitrogen content/g body weight). Likewise, cortisone injection reduces the number of newborns, and, significantly, the individual weight of the same. At the 21st gestation day, the nitrogen content of the litter, given by g of weight, is also significantly reduced. Liver activity of PEPCK was significantly increased in the pregnant rat in all days under study and was not detected in the foetus in the 21st day.

Animal Nutritional Physiological Phenomena↗
PubMed1982

[Effect of the dietary protein level and hydrocortisone acetate treatment to pregnant rats on the newborns].

The influence of dietary protein level (three diets provided with 4% (D1), 12% (D2) and 14% (D3) of protein were tested) and hydrocortisone acetate administration (4 mg/100 g body wt. were daily injected), to rats during pregnancy, were studied. The parameters considered were the number, weight and nitrogen content of the litter. The D3 diet caused a significant increase in the newborns number, whether the mothers were hormone-treated or not. Cortisol associated to the D1 diet led to an appreciable fall in this parameter. Total N content of the litter, which had revealed independent of the dietary protein level in the control groups (rats without hormonal treatment), decreased significantly after cortisol administration in both the three experimental groups. This latter effect was more intense in litters coming from rats fed on the D1 diet. When the N content is expressed as mg N/g litter weight, this parameter decreased significantly only when the cortisol treatment was associated to the D1 diet.

Animals↗
PubMedDate not supplied

[Evaluation of the body composition by anthropometry and bioelectric impedance in a group of elderly patients recovering from cerebrovascular accidents].

Body composition was assessed by bioelectrical impedance and anthropometry in 25 subjects, 13 men and 12 women aged 68 +/- 9 with approximately 1 year of recovering from stroke. Most of them with a high independence in their diary activities. The main purpose of this study is to know the body composition of elderly patients with this pathology and how affects the two compartments, fat mass and fat free mass when they are measured by two different techniques anthropometry and BIA. Body Mass Index was higher in women than in men and correlation coefficient (r = 0.6) with body fat per cent was similar with both methods: BIA and anthropometry. The body fat per cent values obtained by BIA showed the same trend to be lower for men than for women and in general were higher than the anthropometric values; the high correlation between the body fat per cent by anthropometry and by BIA support this tendency (r = 0.748, p < 0.01). The comparative studies of ours results in elderly subjects recovered from stroke and the literature data in healthy elderly subjects suggests that this pathology do not lean to important changes in body composition. However, further research is necessary to confirm these results.

Aged↗