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T Gaál

Publications and source records attributed to T Gaál.

At least 19 recordsLinked to original sources
PubMed2006

Free radicals, lipid peroxidation and the antioxidant system in the blood of cows and newborn calves around calving.

The oxidative stress of birth in cattle (Bos taurus) was evaluated by measuring steady state concentration of free radicals in whole blood, rate of lipid peroxidation and activity of antioxidant enzymes in erythrocytes, antioxidant capacity of blood plasma in 14 calves at birth and four times after birth until 3 weeks of age and also in their mothers at calving. The same parameters were also measured in 58 dairy cows before calving, at parturition and after calving. Free radical concentration in the blood of newborn calves was higher than in cows confirming that birth means oxidative stress for calves. Red blood cell malondialdehyde in calves was the highest at birth and following the first solid feed intake at the third week. Superoxide dismutase activity increased in calves during the first three weeks of life. Ferric reducing ability of plasma was higher in calves at birth than in cows and decreased thereafter. Higher superoxide dismutase activity in red blood cells and lower ferric reducing ability of plasma in dairy cows was found at calving compared to the average of all pre- and post-calving results. We conclude that the blood of newborn calves is well prepared to deal with the oxidative stress of birth, and that such a stress is present even when some fingerprint markers of redox imbalance show no apparent alterations. Stress of calving has minor effects on the antioxidant system of cows.

Animals↗
PubMed2005

Morphological evaluation of canine platelets on Giemsa- and PAS-stained blood smears.

The morphology of canine platelets (changes in size, shape, staining characteristics, degree of activation and clump formation, distribution of granules, appearance of vacuoles on Giemsa-stained smears) was investigated in 20 healthy control and 181 diseased dogs. In the group of the sick dogs 84 animals suffered from disorders affecting directly the haematological parameters or the haematopoietic organs such as bleeding, thymic haemorrhage, haemolytic disorders, lymphoma, immune-mediated thrombocytopenia, and other 97 dogs were affected by other diseases (hepatopathy, nephropathy, hepatic, splenic or intestinal neoplasm, skin diseases, diabetes mellitus, Cushing's syndrome, sepsis). The alterations found in platelet morphology were not specific for any disorder. The most common platelet abnormalities were polychromasia and the presence of giant platelets. These changes occurred in a high number in disorders accompanied by bleeding or haemolysis. Anisocytosis was the most frequent finding in hepatic, splenic or intestinal neoplasms and in certain endocrinopathies. Microcytosis was observed in immune-mediated thrombocytopenia, hepatic neoplasms and endocrine disorders. Extreme platelet activation was common in haemolysis, hepatopathies, neoplastic diseases and sepsis. Vacuolisation was present in thymic haemorrhage, pancreatitis, diabetes mellitus and Cushing's syndrome. A new morphologic phenomenon, i.e. a ring-like formation of granules, was described in the cytoplasm of the platelets both in healthy and diseased animals. In addition, two forms of pathologic granulation were also described for the first time in Giemsa-stained blood smears: the pseudonuclear and the spot-like formation of granules, which were observed especially in disorders affecting the blood cells. The granulation and morphological characteristics of platelets on smears stained by periodic acid-Schiff reaction (PAS) were also studied. Three localisations of granulation were observed, such as peripheral, eccentric and diffuse. The ratio of PAS-positive and -negative platelets was evaluated in several diseases. Our findings support the diagnostic value of platelet evaluation by light microscopy and help clinicians/clinical pathologists to understand why morphologic changes of thrombocytes might be expected in several diseases.

Animals↗
PubMed2004

Effect of supplementation with methionine and different fat sources on the glutathione redox system of growing chickens.

The effect of supplementary methionine and fats of different saturation levels on the glutathione redox system of growing broiler cockerels was studied. The diet of three groups of chicks was supplemented with corn germ oil, beef tallow and fish oil at the levels of 30 g/kg and 50 g/kg of feed, respectively. The diet of further three groups was supplemented with methionine (5 g/kg of feed) in addition to the different fat sources. Control chicks were fed with a compound feed without methionine and fat supplementation. Reduced glutathione (GSH) and glutathione disulphide (GSSG) content as well as glutathione peroxidase activity in the liver were determined and GSH/GSSG ratio was calculated at day old and then at one and three weeks of age. Our results indicate that supplementary methionine stimulates both the synthesis of the glutathione redox system and glutathione peroxidase activity in growing chickens in the first period of postnatal life, when the risk of lipid peroxidation is high due to feeding unsaturated fats in the diet.

Animal Feed↗
PubMed2002

Relationship between concentration of citrate and ketone bodies in cow's milk.

The authors' hypothesis is that the members of the tricarboxylic acid cycle (TCA cycle) such as citrate decrease in association with increased ketone body formation. To prove this hypothesis the connection between ketone bodies and citrate formation of milk was studied. A fluorimetric method was used to determine citrate and a headspace sampling gas chromatographic (GC) method was developed for determination of ketone bodies. Under real conditions of milk sampling, transport and storage, preserved milk samples of 119 clinically healthy dairy cows obtained in the 48 hours after milking were investigated. A low level of acetoacetate (ACAC) was found in all samples. This fact can be explained by the spontaneous decarboxylation of acetoacetate during sample storage (previously decarboxylised acetoacetate = pdACAC) and, consequently, the majority of the amount of acetoacetate in the samples (AC + pdACAC) appeared in the measured acetone concentrations. Based on the measured acetone concentration of milk samples two groups were formed retrospectively: HA (high-acetone) group (n = 41) with an AC + pdACAC concentration of > 0.4 mmol/l and a LA (low-acetone) group (n = 78) with an AC + pdACAC level of < or = 0.4 mmol/l. In the milk of cows of Group HA a positive correlation (r = +0.623) and linear connection between acetone (AC + pdACAC) and beta-hydroxybutyrate (BOHB) levels was found [BOHB = 2.491 + 0.586 x (pdAC + ACAC)]. Furthermore, in this group a negative correlation between citrate and BOHB and AC + pdACAC was also established (r = -0.579). Focusing on the results of this group the authors found a significant drop of AC + pdACAC and citrate during the metabolically critical first 1-4 weeks of lactation. For this reason they suggest that simple, easy, automated methods (i.e. flow injection analysis, Fourier transformation infrared analysis) should be introduced for the simultaneous determination of acetone and citrate concentration in milk to make the evaluation of the energy status of high-producing dairy cows easier and more certain.

Animals↗
PubMed2002

Effect of deferoxamine and L-arginine treatment on lipid peroxidation in an intestinal ischaemia-reperfusion model in rats.

This study investigated lipid peroxidation (LPO) changes during intestinal ischaemia-reperfusion with and without deferoxamine or L-arginine treatment. White Wistar rats were allotted into four groups as follows: sham-operated (Group SOP), ischaemia-reperfusion only (Group I/R), I/R with deferoxamine (Group D) or L-arginine (Group A) treatment. Concentration of thiobarbituric acid reactive substances (TBARS), overall concentration of malondialdehyde and 4-hydroxy-alkenals (LPO586), activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX) of the jejunal homogenates were determined. The same analytes except LPO586 were assayed in RBC haemolysates. Measurements of ferric reducing ability (FRAP), total antioxidant status (TAS) and nitric oxide (NO) concentrations of plasma samples were also completed. The only significant change observed in the SOP group was an increased SOD activity after the ischaemic period. In the I/R group significant increase of intestinal LPO586 concentration was observed during hypoxia that was followed by similar changes in intestinal and RBC TBARS and plasma FRAP values upon reperfusion. In Group D the intestinal TBARS and LPO586 concentrations were significantly lower while FRAP and NO concentrations were significantly higher compared to the I/R group. At the same time RBC TBARS concentration and GPX activity significantly decreased within Group D. In Group A the intestinal LPO586 concentration was significantly lower than in the I/R group whilst RBC TBARS concentration showed a similar pattern. Plasma FRAP and NO concentration showed similar changes to those seen in Group D. It is concluded that I/R increased the LPO in the intestinal tissue and altered some parameters of plasma and RBCs, too. Deferoxamine treatment prevented these effects, while the usefulness of L-arginine remained doubtful.

Animals↗
PubMed2002

Percutaneous ultrasound-guided cholecystocentesis in dogs.

Percutaneous ultrasound-guided cholecystocentesis was performed on 13 healthy beagle dogs to determine whether percutaneous ultrasound-guided cholecystocentesis in the dog was a feasible and safe procedure. Clinical, laboratory and ultrasonographic examinations were done at 0 and 10 minutes, in the 2nd and 16th hour, and on the 7th day. They included a detailed physical examination of the mucous membranes, cardiorespiratory system and abdominal organs. Laboratory examinations of the blood consisted of a complete blood count, determination of packed cell volume (PCV), haemoglobin (Hb), total plasma protein (TPP), parameters of haemostasis including prothrombin time (PT), activated partial thromboplastin time (APTT), and enzyme activities reflecting hepatobiliary function, i.e. aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT). Ultrasonographic findings of the gallbladder (size, shape, wall, content) and appearance of the biliary tract and the surrounding cranial intraabdominal organs were also evaluated. Percutaneous ultrasound-guided cholecystocentesis was performed easily during the study, and dogs tolerated well the procedure performed without anaesthesia. All laboratory parameters of the blood remained within normal limits throughout the study. However, some follow-up values, i.e. PCV, TPP, APTT and ALT, demonstrated statistically significant differences when compared to baseline measurements, which might reflect the effect of 24-hour fasting before the experiment, as well as day-to-day metabolic fluctuations due to feeding and water supply during the study. There were no visible signs of bleeding from the liver, bile leakage from the gallbladder or accumulation of free peritoneal fluid during repeated ultrasonographic examinations. Percutaneous ultrasound-guided cholecystocentesis seems to be an important diagnostic procedure in canine gallbladder diseases and can be used safely and easily to gain gallbladder bile for diagnosis of bacterial cholecystitis or for investigating hepatobiliary function in the dog.

Animals↗
PubMed2001

Chronic hepatitis in the dog--a review.

Chronic hepatitis is a heterogeneous group of inflammatory-necrotizing diseases of the liver. There is controversy in both human and veterinary medicine about the classification of chronic hepatitis and this is likely to remain until a classification based on aetiology rather than on morphology is introduced. Controversy exists as to whether chronic hepatitis in dogs is comparable to the human disorder. The aetiology of chronic hepatitis in dogs is poorly understood, whereas in humans an increasing number of viral causes have been found. Liver biopsy is essential for the diagnosis of chronic hepatitis both in dogs and in humans. Histopathological evaluation of the liver is required to make the diagnosis, which is based on the presence of liver cell necrosis and inflammatory reaction. The proposed criteria for the classification of hepatitis in dogs are then as follows: aetiology is the primary denominator (infectious, drug induced, autoimmune, or, if unknown, idiopathic). The other criteria are histopathological, with severity reflecting the severity of the necro-inflammatory activity (minimal, mild, moderate or severe) and chronicity reflecting the extent of fibrosis (none, mild, moderate, severe or cirrhosis).

Animals↗
PubMed2001

Biochemical and antioxidant changes in plasma and erythrocytes of pentathlon horses before and after exercise.

Physical exercise in the horse induces a series of normal physiological and biochemical adaptations. Increasing metabolism and oxygen uptake may induce oxidative stress in various organs. The aim of this study was to examine exercise-induced changes in some plasma and RBC biochemical and antioxidant variables in pentathlon horses. Blood samples were taken from 14 horses before, immediately after, and 24 hours after competing in two 1-minute runs of intense exercise over jumps. The peak intensity periods were preceded by a 20-minute warm-up and separated by a 20-minute break. The following plasma biochemical analytes were determined: total protein, uric acid, and lactate concentrations, and lactate dehydrogenase (LDH) and creatine kinase (CK) activities. Total antioxidant status (TAS) and the ferric reducing ability of plasma (FRAP) also were measured. Thiobarbituric acid-reactive substances (TBARS), reduced glutathione (GSH), and total protein concentrations, and glutathione peroxidase (GSHPx) and superoxide dismutase (SOD) activities were determined in RBC hemolysates. Significantly increased concentrations of total protein, lactate, and FRAP, and increased activities of CK and LDH were observed immediately postexercise compared with pre-exercise samples (P<0.05). All results returned to approximately initial values after 24 hours of rest. RBC GSH and TBARS concentrations did not change immediately after exercise, but decreased after 24 hours of rest (P<0.05). Plasma uric acid and FRAP values were positively correlated in a linear model (r = 0.78). In summary, the type of exercise applied in this study, which can be considered quite usual for pentathlon horses, caused detectable biochemical and lipid peroxidative changes in plasma and RBCs. FRAP and TAS values changed in opposite directions, indicating that when antioxidant capacity is assessed using different methods, highly different results may be obtained.

Journal Article↗
PubMed2001

Rate of lipid peroxidation in brain and liver tissues and the total antioxidant status of blood plasma in developing chicks.

Age-related changes of tissue lipid peroxidation (LPO) of liver and brain, as well as plasma antioxidant capacity of broiler chicken cockerels were investigated. Tissue LPO was characterised by the spectrophotometric assessment of thiobarbituric acid reactive substances (TBARS). Plasma antioxidant power was evaluated by the measurement of total antioxidant status (TAS). Newly hatched broiler chicks had similar TAS value (1.19 mmol/l) as newborns of mammalian species. Significant changes (p < 0.05) were observed in the time course of all parameters. Tissue TBARS concentration was higher in the brain than in the liver at hatching, while the latter organ was found to have more effective antioxidant defence during embryonic life. The concentration of TBARS increased up to the 10th day in the liver but only up to the 21st day in the brain, and the former was accompanied by an approximately 50% decrease of plasma antioxidant capacity. This suggests that the liver plays an important role in forming the antioxidant defence mechanisms of the blood plasma in broiler chicks.

Age Factors↗
PubMed2000

Dog feeding test for assessing the nutritional adequacy of practical diets.

The nutritive value of dog foods declared by the manufacturer as nutritionally complete and balanced can be best assessed by feeding trials with dogs. A protocol of a feeding trial has been developed and tested with working dogs fed two different commercial complete and balanced diets for 8 weeks. The parameters used for evaluating the effect of diets were general health status, body and hair coat condition, change of body weight, haematological parameters (white blood cell (WBC) count, red blood cell (RBC) count, haemoglobin, packed cell volume), and biochemical parameters in blood serum (alanine aminotransferase, urea, albumin). The trial protocol proved to be appropriate to monitor the dogs' nutritional status and to reveal differences between diets. This method of evaluation is recommended for use in supporting the nutritional claims (labelling) of dog foods.

Animal Feed↗
PubMed2000

Effects of saturated and unsaturated fats with vitamin E supplementation on the antioxidant status of broiler chicken tissues.

The influence of fish oil (highly unsaturated) and beef tallow (highly saturated) with vitamin E (100 IU/kg) supplementation on the antioxidant status of broiler chicken cockerels was investigated. Chicks were fed a control diet with no added fat, 40 g/kg each of fish oil and beef tallow diets, respectively, from 11 to 42 days of age. Tocopherol concentration and the rate of lipid peroxidation, thiobarbituric acid reactive substance (TBARS) in liver, fatty acid composition of the liver lipids, blood serum total antioxidant status (TAS), and reduced glutathione (GSH) content were determined. Vitamin E supplementation of the diet increased liver alpha-tocopherol content in chicks regardless of the type of dietary fat. Fish oil diet resulted in higher liver TBARS value while beef tallow diet showed lower values compared to the control diet. Vitamin E supplementation reduced liver TBARS as well as serum GSH, and raised serum TAS for all diets. Serum GSH was the same for vitamin E supplemented diets regardless of the fat supplement. Fish oil diets resulted in a significant increase in hepatic lipid n-3 PUFA content. A significant positive correlation was found between liver TBARS and n-3 PUFA content. No relationships were established, however, between liver TBARS and n-6 PUFA or saturated fatty acids. The results suggest that feeding oils rich in n-3 PUFA increases tissue concentration of these fatty acids, consequently increasing tissue lipid peroxidation and reducing the antioxidative status of broiler chickens. Supplementing high levels of vitamin E with such oils may increase tissue oxidative stability. Serum TAS or GSH may be used as a measure of antioxidative status in chickens.

Animal Feed↗
PubMed1997

Epidemiology of congenital coronary artery anomalies: a coronary arteriography study on a central European population.

The anatomical patterns and frequency of occurrence of congenital coronary anomalies (CCA) in a Central European cohort has not yet been studied. The angiographic data of 7,694 consecutive patients undergoing coronary arteriography at the Albert Szent-Györgyi Medical University, Szeged, Hungary, from 1984 to 1994 were analyzed. CCA were found in 103 patients (1.34% incidence). Ninety-eight of them (95.2%) had anomalies of origin and distribution, and five (4.8%) had coronary artery fistulae. The incidence was the highest for the separate origin of left descending artery and left circumflex from the left sinus of Valsalva (52.42%). Anomalous origin of the left circumflex coronary artery from the right coronary was 8.7% while from the right sinus of Valsalva 18.4%. CCA, which may be associated with potentially serious events, such as ectopic coronary origin from the opposite aortic sinus (1.9%) and single coronary arteries (3.88%), were not frequent. The incidence of CCA in the Central European cohort under study was similar to that of the largest North American study. The anatomic classification presented can be useful from both clinical and surgical standpoints.

Adult↗
PubMed1997

Changes in some red blood cell and clinical laboratory parameters in young and old Beagle dogs.

Routine laboratory and lipid peroxidase parameters in the blood of Beagle dogs under 1 year of age (7 males, 7 females) and over 9 years of age (7 males, 7 females) were compared. The mean corpuscular haemoglobin (MCH) and haemoglobin (Hb) values, plasma total protein (TP) and globulin concentrations in the older dogs were significantly higher than in the younger ones by 13%, 6%, 10% and 15%, respectively. The plasma inorganic phosphate concentration, however, was 30% lower in the older dogs than in the young ones. The concentration of malondialdehyde (MDA) was 30% higher, while the glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities were around twice as high in the older dogs as in the young ones. However, in the older males the concentration of reduced glutathione (GSH) was 43% and in the older females 9% less than in the young ones. Extremely high levels of MDA and low levels of GSH were only found in the older males. GSH-Px and SOD activities were significantly higher in the older male dogs than in the young ones. The activities of these enzymes were highest in the older females. From our results, we suspect that old dogs, especially males, are particularly exposed to the harmful effects of free radicals and lipid peroxidation.

Aging↗
PubMed1997

Nutritional metabolic diseases of poultry and disorders of the biological antioxidant defence system.

Deficiencies or disturbances of nutrition cause a variety of diseases and can arise in different ways. The amount of a particular nutrient in the diet may be insufficient to meet the requirements, the diet may contain substances that inactivate the nutrient or inhibit its absorption/utilisation, or metabolism may be upset by the interaction of dietary and environmental factors. Peroxidation of lipids or oxygen free radical generation in general is a physiological process important for cell metabolism, division and differentiation and also for the biosynthesis of hormones and prostaglandins. Free radicals generated through these processes are effectively scavenged by the antioxidant defence system. Uncontrolled lipid oxidation caused by disturbances of that system may play a crucial role in some important poultry diseases and toxicoses. The first route of lipid peroxide loading of the organism is via the feed, such as through oxidised lipids. Oxidised fatty acids are absorbed from the intestine mainly in the form of unsaturated keto compounds and initiate lipid peroxidation in the tissues. The second problem is the insufficient amount of antioxidants in the feed, e.g. vitamin E deficiency. Nutritional encephalomalacia is a problem in poultry production which depends both on the actual vitamin E supply and the dietary amount of polyunsaturated fatty acids. In young birds the primary target of vitamin E deficiency is the brain because it contains low amounts of vitamin E, and the vitamin E content of the liver acting as store decreases rapidly during the first week of life. Besides vitamin E, other components of the antioxidant system, e.g. the antioxidant enzymes (catalase and glutathione peroxidase) also have low activity in the brain as compared to other major tissues. The brain is highly susceptible to oxidative stress because of the accumulation of polyunsaturated fatty acids. The third source of free radical generation is the toxic level of different feed ingredients, e.g. toxicoses caused by vitamin A, selenium, and ionophore antibiotics. Other important aspects of antioxidants (e.g. vitamin E and selenium) in poultry are stimulation of the immune response (e.g. in the case of vaccination) and reduction of the risks of free radical formation as a result of macrophage function.

Animals↗
PubMed1996

[Correlations between clinical picture and coronary angiography in unstable angina].

In a one year period (from 01.07. 1993 to 30. 06. 1994) 103 patients were admitted to the Central Intensive Care Unit of the Albert Szent-Györgyi Medical University with the diagnosis of unstable angina. In this cohort of patients the authors assessed the correlation of clinical and angiographic data. Significant coronary artery disease was found in 84% (85 patients), single-vessel disease in 23% (24 patients), double-vessel disease in 38% (29 patients), triple-vessel disease in 20% (21 patients), left main stenosis in 8% (8 patients). The culprit lesion was determined in 73 cases. The distribution of the culprit lesion severity was the following: 50-70% in 17% (12 cases), 70-90% in 27% (20 cases), greater than 90% in 44% (32 cases), 100% in 12% (9 cases). Simplex lesions were seen in 43 cases, complex lesions in 9 cases, diffuse irregularities in 5 cases and total occlusions in 9 cases. Abnormalities indicating intracoronary thrombin-us were seen on 5 coronarograms. No correlation could be demonstrated between the clinical classes according to Braunwald and the angiographic morphology.

Adult↗
PubMed1996

Influence of a deficient intake of high and low degradable protein on body composition, metabolic adaptation, production and reproductive performance in early lactation dairy cows.

High-yielding dairy cows (n = 34) were divided into high (HD) and low (LD) protein degradability groups after delivery, and used for a feeding trial which lasted up to day 80 +/- 10 of lactation. The cows were regularly weighed, their body condition was scored (BCS), and their reproductive status assessed. Blood samples were taken simultaneously, and ruminal fluid was collected on the last day of the trial. On postpartum day 45 +/- 6 and 11 days thereafter two prostaglandin F2 alpha (PGF2 alpha) injections were administered. The ammonia and urea concentrations of the ruminal fluid were higher in cows of group HD. The C2:C3 ratio was 2.7:1 vs. 2.3:1 in HD and LD cows, respectively. The amino acid and lipid composition of blood reflected the dietary treatments. The BCS and blood urea concentration were slightly higher in HD animals. The average daily milk production of LD cows was 1.5 kg higher than that of HD cows. The pregnancy rates of the two groups at day 200 after calving did not differ, but LD cows showed their first visible oestrus and reconceived significantly (p < 0.05) later. It can be concluded that--at a marginal energy supply-a moderate (13%) deficiency of rumen-degradable protein during the first 10 weeks after calving can be more detrimental to reproductive performance than a severe (27%) deficiency of undegradable protein.

Adaptation, Physiological↗
PubMed1995

[Unstable angina pectoris associated with surgically treated coronary artery atresia].

A case report of a rare, presumably congenital form of "single coronary artery", is presented. The authors review the classification and clinical significance of the entity with special emphasis with regard to anginal symptoms and the so called sudden unexpected death syndrome. Details and result of surgical intervention (conventional aorto-coronary saphenous bypass) are discussed.

Angina, Unstable↗