Biomedical subjects

T Gaál

Publications and source records attributed to T Gaál.

At least 37 records · Page 2Linked to original sources

PubMed1995

Evaluation of blood lipid peroxidation parameters in carbon tetrachloride (CCl4) toxicity in sheep.

Seven female, 2-year-old, nonpregnant, Merino ewes were treated with a nonlethal dose of 0.3 ml/kg body mass carbon tetrachloride (CCl4) in 1:1 v/v dilution with paraffin oil via a stomach tube into the rumen. Blood samples were collected one day before and on the first, second, third, seventh and tenth day after toxin exposure to study the changes of the lipid peroxidation (LP) status of red blood cell haemolyzate (RBC-haem). The severity of liver damage was monitored by determination of aspartate aminotransferase (AST) activity and bilirubin concentration in the blood plasma. Twenty-four h after CCl4 exposure all animals became lethargic and anorexic, their heart rate and respiratory rate increased. On the subsequent two days these signs became more severe, but by the 10th day the symptoms disappeared. On the 1st and 2nd day following CCl4 exposure the concentration of malondialdehyde (MDA)--an end product of LP--in RBC-haem significantly increased. A slight decrease was found on the 3rd, 7th and 10th day, but MDA values remained significantly higher than the basal ones. The activity of glutathione peroxidase (GPX) in RBC-haem increased slowly on the 1st and 2nd day, then it rose intensively on the third day. GPX activity remained elevated until the 7th day, but on the 10th day it dropped again. Catalase (Cat) activity in RBC-haem did not show any significant changes during the experiment. AST activity in blood plasma showed a two-fold increase in the first three days; later on the high values decreased. Total and direct plasma bilirubin concentration slightly increased on the 3rd day, then both decreased. LP effects in CCl4-induced hepatocellular injury were significant in sheep, in line with the results of experiments on other species such as rats. The LP effects were demonstrated by the elevated MDA concentration and GPX activity.

Animals↗

PubMed1993

Naturally occurring deuterium is essential for the normal growth rate of cells.

The role of naturally occurring D in living organisms has been examined by using deuterium-depleted water (30-40 ppm D) instead of water containing the natural abundance of D (150 ppm). The deuterium-depleted water significantly decreased the growth rate of the L929 fibroblast cell line, and also inhibited the tumor growth in xenotransplanted mice. Eighty days after transplantation in 10 (59%) out of 17 tumorous mice the tumor, after having grown, regressed and then disappeared. We suggest that the naturally occurring D has a central role in signal transduction involved in cell cycle regulation.

Adenocarcinoma↗

PubMed1993

Effect of fasting on blood lipid peroxidation parameters of sheep.

The effects of three-day fasting and one-day refeeding on some blood metabolites and parameters of lipid peroxidation were studied in eight non-pregnant merino ewes. Fasting produced an immediate decrease in blood glucose accompanied by an increase of free fatty acid, total lipid, total cholesterol and urea in the plasma. Starvation increased the concentration of thiobarbituric acid-reactive substances (malondialdehyde), with a slower but more sustained increase in the plasma than in the red blood cell haemolysate. Changes in glutathione peroxidase activity were the reverse of those in malondialdehyde concentration. Catalase activity was not measurable in plasma but was consistently increased in the haemolysate on fasting. Superoxide dismutase activity in the whole blood haemolysate significantly increased only on the first day of food deprivation. The vitamin E content of plasma showed no significant changes. The results indicate that energy deficiency, a well-known phenomenon in ruminants, affects not only the metabolic parameters of the blood but its lipid peroxidative status as well.

Animals↗

PubMed1993

Changes of lipid peroxidation parameters in dogs with alloxan diabetes.

Diabetic human patients and laboratory animals show abnormalities which can be observed also in enhanced lipid peroxidation (LPO) induced in vitro. It seemed to be necessary to demonstrate the presence of these processes also in dogs with experimentally induced alloxan diabetes. In a 5-day experiment, five 1 to 5-year-old dogs of mixed sex were examined. Blood samples were taken before the intravenous administration of 60 mg alloxan/kg body mass and then daily for a period of 5 days. After the administration of alloxan, the dogs became depressed and lost their appetite. Their urine contained varying concentrations of glucose detectable with a test strip. As compared to the physiological values, blood glucose concentration increased considerably throughout. Alanine aminotransferase (ALT) enzyme activity underwent an 8-fold increase by the 24th hour; subsequently, it remained practically unaltered. The malonyldialdehyde (MDA) concentration of red blood cell (RBC) haemolysate also rose with respect to the basal values. Glutathione-peroxidase (GSH-Px) activity increased only transiently, up to the second day of the experiment; subsequently, its activity dropped below the basal values. Similar changes were found in catalase activity, while the activity changes of superoxide dismutase (SOD) were identical in tendency to the above ones; in fact, it hardly showed any alterations. Besides the severe pancreatic and liver damage caused by alloxan, increased MDA production in the RBC haemolysate indicated enhanced peroxidation of polyunsaturated fatty acids, i.e. intensification of the LPO processes. The increase of GSH-Px and catalase activity, followed by their decrease was suggestive of changes in the enzymatic defence mechanism acting against free radicals.

Alanine Transaminase↗

PubMed1992

[Ergometric stress test using Tl-201 myocardial perfusion. Tomographic or planar imaging?].

The clinical performance of the planar vs. tomographic ergometric stress 201-Tl myocard perfusion scintigraphy was compared. The results of the investigations of 80 patients were analysed retrospectively. In 59 patients planar, in 21 tomographic imaging was performed. As a consequence of clinical decision making cardiac catheterization was made in all of the patients, within 3 months after the perfusion scintigraphy. The sensitivity of the planar method was 23/27 (85%), the specificity 18/32 (56%), the accuracy 41/59 (69%). The respective values of the SPECT technique were: Sensitivity: 12/12 (100%), specificity 6/9 (66%), accuracy 18/21 (86%). It is concluded, that in comparison to the planar imaging the SPECT technique is superior in the detection of the perfusion abnormalities of the myocard due to significant coronary narrowings.

Coronary Disease↗

PubMed1992

Effect of bulk feeds (alfalfa hay, corn silage) on the metabolism and liver parameters of growing geese.

Rearing experiments were conducted with a total of 90 liver hybrid geese from Babat, divided into three groups of 30 birds each. The effect exerted by all-concentrate feeding (group 1), concentrate feeding supplemented with alfalfa hay (group 2) or with corn silage (group 3) ad libitum on the blood glucose level, blood plasma total lipid, total cholesterol and free fatty acid level, and on total lipid content of the liver was studied. In addition, aspartate aminotransferase (AST) activity of the blood plasma and carotene, vitamin A and vitamin E concentration of the blood plasma and the liver were determined. It was found that the blood and liver parameters of goose groups fed different diets changed within the physiological limits typical of the species. Excessive fibre intake resulted in reduced lipid transport within the organism at an unchanged plasma cholesterol level; at the same time, blood glucose level remained unchanged. Ad libitum feeding of alfalfa hay and corn silage enhanced carotene and vitamin A transport and carotene storage but did not affect the transport of vitamin E. The results confirm earlier data of the literature that beta-carotene and vitamin A together impair vitamin E metabolism.

Animal Feed↗

PubMed1991

[Diagnosis of femoral pseudoaneurysm and factors contributing to its incidence after heart catheterization].

Two-hundred patients who underwent heart catheterization between 30 November 1989 and 30 September 1990, were followed up to establish the frequency of the vascular complications (mainly femoral pseudoaneurysm) of the procedure. Factors were evaluated which may promote the occurrence of femoral pseudoaneurysms. This complication was diagnosed in 6 cases. Two-dimensional and Doppler echocardiography (conventional and colour-coded) played an important role in the diagnosis. Systemic hypertension, anticoagulant therapy, obesity and technical difficulties (multiple punctures and catheter guidance problems) proved to be factors promoting femoral pseudoaneurysms. Serial echocardiograms revealed a tendency to spontaneous healing even in cases of relatively large pseudoaneurysms.

Aneurysm↗

PubMed1991

[Systemic thrombolysis in acute obstruction of an artificial valve].

Prosthetic valve thrombosis is a characteristic, but fortunately not frequent complication of surgical valve replacement. Its occurrence may lead to haemodynamic catastrophe. Three cases involving prosthetic valve thrombosis are presented. Two patients suffered from thrombosis after tricuspid valve replacement (St. Jude Medical), while the third occurred after mitral valve replacement (Sorin). In the acute phase, systemic thrombolysis was initiated (2 MU Streptokinase during 22-28 hours). The obstruction of one of the tricuspid valves and the mitral valve was eliminated. Lysis of the other tricuspid valve was not complete, but it helped the patient to survive the acute phase until reoperation. Embolization occurred in the inferior extremity after thrombolysis of the mitral prosthetic valve, but it was cured. Two-dimensional and Doppler echocardiography (conventional and colour-coded) played an important role in the diagnosis of the obstruction and in the follow-up of the effectivity of thrombolysis. Systemic thrombolysis may be a lifesaving procedure in acute prosthetic valve thrombosis. In spite of the potentially dangerous complications, it has to be attempted.

Adult↗

PubMed1991

[Judging the severity of regurgitation in acquired heart defects using color-coded Doppler echocardiography].

In the study, 139 valvular regurgitations of 120 patients (55 mitral and 84 aortic regurgitations) were investigated and compared by means of colour flow mapping and heart catheterization. During the echocardiographic examination, the length and width of the regurgitant jets were measured and the jet area was planimetered besides the subjective grades. The above parameters were correlated with the angiographic grades. Good agreement was found between the results of the two methods. As concerns the different parameters of the regurgitant jets in mitral regurgitation, the most severe (grade IV) category was easily distinguished from the others, while in aortic regurgitation all four categories were differentiated by colour flow mapping. These measurements indicated that colour-coded Doppler echocardiography is a suitable tool for detection of the severity of valvular regurgitations in a noninvasive way.

Aortic Valve Insufficiency↗

PubMed1990

[Cardiolite (99m-Tc-isonitrile) SPECT studies in patients prior to coronary bypass surgery].

The authors studied with 99m-Tc Cardiolite (methoxy-isobutyl-isonitrile) SPECT examination the effect of coronary bypass operation on the myocardial perfusion. One week before and 3 weeks after the operation examinations were performed first with dipyridamol loading and 24 hours later in rest. The regional perfusion of the myocardium was studied on the basis of transversal section-pictures of corrected axis position. In the examinations preceding the operation the global sensitivity of the method was found to be 100%. In the demonstration of the structures of the ramus descendens 95%, of the ramus circumflexus and of the right coronary artery 100% sensitivity was reached. In postoperative examinations following the bridging of the ramus descendens anterior the improvement of the perfusion of the corresponding ventricular segment was found in 15/20 during the loading and in 7/8 cases following the bridging of the ramus circumflexus and right coronary artery. Improving perfusion was demonstrated in 17/20 and in 6/8 cases in rest. On the basis of the results the authors consider their method suitable for the study of the regional blood perfusion and for the examination of the changes taking place upon coronary bypass operations.

Aged↗

PubMed1989

[Morphologic studies of emdomyocardial biopsy specimens].

Authors have studied 153 heart biopsies of 120 patients and results of 133 endomyocardial biopsies studied by light and electron microscopy are described. In addition to typical morphological picture of myocarditis, in majority of cases non-specific changes appearing also in idiopathic cardiomyopathy were observed and their ultrastructure is fully stated. Results are compared to relevant data of literature. Indications, informative value, practical and scientific research significance of myocardial biopsies are briefly overviewed.

Biopsy↗

PubMed1989

[The significance of ketonuria in lactating cows].

In two large sized farms in Hungary and in several small and medium farms in Bavaria the authors studied the development of ketonuria in cows after calving. In two flocks without problems 30 percent of the cows developed ketonuria, whereas the rate was 56 percent in one problematic flock. Milk yield of the cows observed was above 5000 kg per year, their age differing only slightly. Cows with ketonuria revealed an increased enzyme activity of AST and a decreased plasma-glucose concentration in comparison to the ketone-free animals. Also, the ketonuria cows showed higher amounts of free fatty acids in plasma and lower amounts of total cholesterol. Additionally, these animals more often revealed reproductive disorders. The rate of culling and emergency slaughter was also increased, whereas their pregnancy rate was decreased.

Animals↗

PubMed1988