Biomedical subjects

S Kocsis

Publications and source records attributed to S Kocsis.

12 recordsLinked to original sources

PubMed2002

The decrease in body fat in mice fed conjugated linoleic acid is due to increases in energy expenditure and energy loss in the excreta.

We carried out energy balance studies in four groups of young, growing, 5-wk-old Balb-C mice (n = 12/group) that were either food restricted or nonrestricted and fed high fat diets (38 energy%) with or without 0.93 g/100 g conjugated linoleic acid (CLA) for 39 d. The energy in carcasses, excreta and food was measured in a bomb calorimeter. CLA lowered the percentage of the energy intake that was stored in the body from 1.9 +/- 0.8 to -2.3 +/- 0.7% (mean +/- SD, P < 0.05) in the nonrestricted mice and from 1.4 +/- 1.3 to -2.9 +/- 0.7% (P < 0.05) in the restricted mice. Thus, the CLA-treated mice had a net loss of body energy. The percentage of the energy intake eliminated in the excreta increased from 7.6 +/- 0.9% in controls to 8.7 +/- 1.0% (P < 0.05) in the CLA-treated mice that were nonrestricted and from 7.3 +/- 0.8 to 8.4 +/- 0.6 (P < 0.05) in the restricted mice. The amount of energy ingested minus the amount retained in carcasses and excreta equals the energy expenditure. The percentage of the energy intake that was expended as heat increased from 90.5 +/- 1.2 in controls to 93.6 +/- 1.5% (P < 0.05) in the CLA-treated nonrestricted mice and from 91.3 +/- 1.5 to 94.5 +/- 1.0% (P < 0.05) in the restricted mice. The lower energy storage in the CLA-fed mice was accounted for by an increase in the energy expenditure (74%) and by an increase in energy lost in the excreta (26%). Feeding CLA also increased liver weight, which may warrant further studies on the safety of CLA.

Adipose Tissue↗

PubMed2001

Specificity and reversibility of the training effects on the concentration of Na+,K+-Atpase in foal skeletal muscle.

The purpose of the present study was to determine whether training and detraining affect the Na+,K+-ATPase concentration in horse skeletal muscles, and whether these effects are specific for the muscles involved in the training programme. Twenty-four Dutch Warmblood foals age 7 days were assigned randomly to 3 groups: Box (box-rest without training), Training (box-rest with training: short-sprint) and Pasture (pasture without training). Exercise regimens were carried out for 5 months and were followed by 6 months of detraining. Five of the foals in each group were subjected to euthanasia at age 5 months and the remaining foals at 11 months. Muscle samples were collected from the deep part of the gluteus medius, semitendinosus and masseter muscles. The Na+,K+-ATPase concentration was quantified by [3H]ouabain binding. In the Training group, the concentration of Na+,K+-ATPase in gluteus medius and semitendinosus muscle, but not in masseter muscle, showed a relative increase of 20% (P<0.05) as compared to Box foals. After detraining for the subsequent 6 months, the concentration of Na+,K+-ATPase in semitendinosus muscle remained the same, while that in gluteus medius muscle was reduced by 10%. It is concluded that: 1) short-sprint training for 5 months induced an increase of the Na+,K+-ATPase concentration in gluteus medius and semitendinosus muscles of the foal. Interestingly, this effect persisted during the 6 months of the detraining period. Whether the higher Na+,K+-ATPase concentration due to training of young foals leads to a better athletic performance when they become mature still needs to be established; 2) the factors that initiate an increase in Na+,K+-ATPase concentration following training are likely to be located in the muscle itself and 3) the training effect may last for several months after returning to normal activity, especially in muscles containing a high percentage of fast-twitch fibres.

Animals↗

PubMed2000

Prolonged food restriction and mild exercise in Shetland ponies: effects on weight gain, thyroid hormone concentrations and muscle Na(+),K(+)-ATPase.

We determined the effects of food supply and low-intensity training on growth, serum thyroid hormone levels and the Na(+),K(+)-pump concentration in equine skeletal muscle. Twenty-two Shetland ponies were subjected to two different feeding regimes for 2(1/2) years (11 ponies per group): food restriction (body condition score kept at 2) or ad libitum fed (body condition score kept at 8). Five ponies in each group underwent low-intensity training. Gluteus medius muscle and serum samples were obtained in April 1998. Subsequently, all ponies were fed ad libitum and the training programme was stopped. Muscle biopsies and serum samples were collected again in November 1998. Food restriction was associated with a 30-50% reduction of body weight gain. While the total thyroxine (T(4)) level was increased, the free T(4) remained at the control level. The serum total tri-iodothyronine (T(3)) and free T(3) were reduced by 30% and 49% respectively. After 6 months of refeeding there were no differences in any of the hormone levels between the ad libitum fed and the food-restricted groups. Food restriction produced a minor, but not significant, decrease in the Na(+),K(+)-pump concentration in the gluteus medius muscle of the Shetland ponies. Low-intensity training reduced weight gain of the ad libitum fed group by 25%, but had no detectable effect on the concentration of the Na(+), K(+)-pumps. We conclude that prolonged food restriction in Shetland ponies results in a weight gain reduction of 30-50%, and is associated with similar decreases in serum total and free T(3). The reduction in serum T(3) only slightly influenced the Na(+), K(+)-ATPase concentration in skeletal muscle, indicating that muscle tissue of different species may respond differently to changes in circulating thyroid hormones.

Animals↗

PubMed1999

High calcium intake lowers apparent digestibility of energy in veal calves.

Veal calves aged 8 weeks were fed iso-energetic amounts of milk replacers with either a low (7.1 g of calcium/kg of air-dry diet) or a high concentration of calcium (11.6 g of calcium/kg of air-dry diet) for a period of 10 weeks. The extra calcium was added in the form of calcium formiate. Final body weight of the two dietary groups was similar. Faeces were collected during the final week of the trial. The high calcium diet raised faecal dry matter output by 87% and faecal energy by 70%. The extra output of faecal dry matter was composed of 36% and 37% of crude fat and ash, respectively. The extra faecal energy output was for 75% in the form of crude fat. The high versus low calcium intake not only depressed apparent digestibility of total lipids but also that of crude protein, carbohydrates and ash. It is concluded that a high calcium intake by veal calves reduced energy availability without affecting body weight gain.

Animals↗

PubMed1998

Age variance of left ventricular diameters in dogs with cardiac disease.

Ventricular size increases during growth, but often due to cardiac disease. This study aims to describe left ventricular dimension interrelations using a representation that is applicable to patients with cardiac disease, and subsequently to statistically study possible age and gender influences in a large population. In retrospect we analyzed echocardiographically obtained diameters of the left ventricle in 442 dogs of various breeds with congenital or acquired heart disease. Also, we compared our findings with published data on humans and other animals. Multivariate regression analysis was applied to assess possible influences of age and gender. A high correlation was found for end-systolic diameter (ESD) versus end-diastolic diameter (EDD): ESD (cm) = -1.01 cm + 0.93 x EDD (cm) with r = 0.94, p < .00001. Next, these patients were categorized into three age groups (divisions at 3 and 7 years). We detected a slight age dependent effect: the regression coefficients for the younger group differed from the two older groups. No significant gender-related influence was detected. The observation of a high correlation for the ESD versus EDD relationship could be confirmed by reanalysis of published data on normal individuals and human patients. The newly described relationship between ESD and EDD applies in particular to cardiac patients. This is a relevant finding, because clinically important indices of ventricular performance generally depend on ESD, EDD or both. Thus, ESD versus EDD offers a convenient framework for studies on cardiac volume regulation and performance in the cardiopathological spectrum, while permitting incorporation of modulating effects related to age.

Age Factors↗

PubMed1992