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T Takács

Publications and source records attributed to T Takács.

At least 55 records · Page 3Linked to original sources
PubMed1994

Time-course changes in pancreatic laboratory and morphologic parameters in two different acute pancreatitis models in rats.

The aim of this work was to study in rats the temporal course of laboratory parameters and morphologic features in acute pancreatitis induced by cholecystokinin octapeptide (CCK-8) or by a closed duodenal loop. Pancreatitis was induced either with an overdose of CCK-8 (3 x 75 micrograms/kg at 1 h intervals) or by ligation of the duodenum on both sides of the bilio-pancreatic duct. The animals were examined at 0, 2, 4, 8, 16 and 24 h after AP induction. In CCK-8-induced acute pancreatitis, the pancreatic weight/body weight ratio (8.2 +/- 1.1 mg/g) and the amylase level (44.8 +/- 7.5 x 10(3) U/ml) were significantly increased vs. the controls (4.5 +/- 0.8 mg/g and 3.3 +/- 0.2 x 10(3) U/ml, respectively) 2 h after the intervention. The plasma CCK was significantly increased at 4 h (4.55 +/- 1.7 pM) and remained elevated thereafter. The tissue malonyldialdehyde concentration was significantly elevated at 8 h (0.28 +/- 0.07 mumol/mg pancreas) vs. the controls (0.20 +/- 0.02 mumol/mg pancreas). In closed duodenal loop-induced acute pancreatitis, the ratio pancreatic weight/body weight steadily increased during the study; it reached its maximum level at 24 h (7.1 +/- 0.5 mg/g) vs. the sham-operated control (4.8 +/- 0.9 mg/g). The serum amylase level was significantly elevated at 2 h (47.1 +/- 9.3 x 10(3) U/ml), and then decreased steadily. Plasma CCK values were significantly higher than the controls throughout the study. A significant increase in the tissue malonyldialdehyde concentration (0.94 +/- 0.15 mumol/mg vs. 0.20 +/- 0.01 mumol/mg pancreas) appeared at 4 h. Our data indicate that in CCK-8-induced acute pancreatitis the laboratory signs of pancreatitis are most expressed at 4 h, whereas the morphologic changes culminate 8 h, following the last CCK injection. In closed duodenal loop-induced acute pancreatitis, the histologic findings showed a progressive deterioration. Endogenous CCK and oxygen-derived free radicals seem to play a role in the pathogenesis of both types of acute pancreatitis.

Acute Disease↗
PubMed1994

Production of antibodies against adenovirus hexons in Escherichia coli by recombinant phages (a note).

For the study of complex antigen structures, such as the adenovirus hexon capsomer, monoclonal antibodies proved to be very useful tools. Production and stabilization of monoclonal antibodies in a larger amount is complicated and requires special infrastructural background, if we apply the convential hybridoma techniques. Recombinant DNA and gene amplification technology, however, has made it possible to clone antibody genes in bacteria, and to produce antibodies in bacterial cultures.

Adenoviridae↗
PubMed1991

Perspectives of CCK antagonists in pancreatic research. Part II. Experimental studies.

In this article, the effects of different classes of cholecystokinin (CCK) receptor antagonists in CCK-related physiological processes of the pancreas have been discussed. Both glutaramic acid derivatives and natural (benzodiazepine) analogs are potent, competitive antagonists of peripheral CCK receptors. These compounds thus provide a powerful tool for investigating the physiological and pharmacological actions of CCK in the gastrointestinal system, and have already clarified the role of CCK in pancreatic secretion and trophism or growth.

Animals↗
PubMed1990

Bacterial contamination of the uterus after parturition and its effect on the reproductive performance of cows on large-scale dairy farms.

The bacteriological status of the uteri of 150 cows was examined on 14 large-scale dairy farms 10 to 20 d after parturition and then twice again in 2-wk intervals during uterine involution. The degree of bacterial contamination and the proportion of the infected uterus as well as the composition of the isolated flora were determined. The antibiotic sensitivity of the important bacterium strains was also studied. The relationship between the reproductive data and bacterial contamination of the uteri was analyzed, and the influence of certain environmental and genetic factors on the rate of infection was examined. The proportion of cows having moderate or more serious uterine infection remained above 30 % at the end of involution on more than 35 % of the farms. Infections were caused mainly by streptococci, E. coli and corynebacteria. The bacterium strains showed broad resistance against commericially available antibiotics. There were significant differences in the length of time from the parturition to the first insemination and conception among cows at the various farms. There was a significant correlation between these differences and the bacteriological status of the uteri. Reproductive data were the lowest in the group of cows infected with Corynebacterium pyogenes. The rate of the infected uteri was considerably higher after the third parturition and in cows producing less than 20 l of milk per day. No connection was found between the bacteriological status of the uteri and the breed, type of housing, and season of the parturitions.

Journal Article↗
PubMed1990

The effect of CR 1409, a potent CCK receptor antagonist, on basal and stimulated pancreatic secretion in rat.

The effect of a specific cholecystokinin (CCK) receptor blocker from Rotta Research Laboratorium (Monza/Milano, Italy), CR 1409 (Lorglumide), on pancreatic secretion was investigated. CR 1409 caused a rightward and parallel shift in the dose-response curve of CCK-8-stimulated pancreatic protein secretion in anesthetized rats, demonstrating a competitive mechanism of inhibition. The mean pA2 value, showing the 50% inhibitory dose of CR 1409, was 6.4. CR 1409 proved to be about 1,000 times more potent as a CCK receptor blocker than proglumide, the first glutaramic acid analogue with anti-CCK potential. In conscious rats, pancreatic protein and water secretion were significantly diminished for about 2 h in response to 300 micrograms/kg of CR 1409 given subcutaneously during diversion of pancreatic juice, demonstrating inhibition of endogenous CCK by this new glutaramic acid derivative. By contrast, during reintroduction of precollected pancreatic juice into the duodenum, when the release of CCK is almost totally eliminated, pancreatic secretion was not modified by the same dose.

Animals↗
PubMed1990

The effect of long-term administration of lorglumide (CR 1409) on rat pancreatic growth and enzyme composition.

The effects of lorglumide (CR 1409), a potent cholecystokinin (CCK) receptor blocker developed recently by the Rotta Research Laboratories, were studied on pancreatic growth and enzyme composition. In secretory studies, the inhibitory effect of 4 mg/kg of lorglumide administered subcutaneously proved to last more than 3 h. The trophic effect of exogenous CCK (600 ng/kg given three times daily for 2 weeks) was significantly decreased by the simultaneous administration of 4 mg/kg of lorglumide. To study the role of endogenous CCK released by feeding while maintaining pancreatic trophism, 4 mg/kg of lorglumide was administered subcutaneously four times daily during the feeding period for 2 weeks. Lorglumide significantly decreased pancreatic weight, pancreatic content of soluble protein, trypsinogen, and chymotrypsinogen, while decreases in DNA, lipase, and amylase failed to reach statistical significance. According to our experiments, high-doses of lorglumide could inhibit not only the trophic effect of exogenous CCK but also the effect of endogenous CCK released by food and lorglumide itself.

Amylases↗
PubMed1989

Mechanisms of action of alcohol administration on the trophic effect of soybean trypsin inhibitor and cholecystokinin octapeptide in rat.

Influence of alcohol administration on the trophic effect of cholecystokinin-octapeptide and soybean trypsin inhibitor administration was examined in male Wistar rats. Two x 4 mL of 20% alcohol given intragastrically during 2 wk did not significantly influence pancreatic weight, DNA, protein, trypsin, chymotrypsin, amylase, lipase, or trypsin inhibitor contents of the pancreas. It diminished the hypertrophy but not the hyperplasia seen after CCK-8 treatment, and eliminated the hyperplasia, as well as the hypertrophy provoked by SBTI administration. Secretory studies and CCK measurements demonstrated decreased CCK release in response to SBTI stimulation after 3-d alcohol administration. The results indicate that alcohol inhibits the enzyme synthesis of the CCK stimulated dividing and/or newly formed acinar cells and the endogenous CCK release.

Amylases↗
PubMed1988

The anti-CCK effect of glutaramic acid derivatives in anesthetized and conscious rats.

The effects of specific gastrin-cholecystokinin (CCK) receptor blockers (proglumide and a new, more potent product of Rotta Research Laboratorium, CR-1392) on pancreatic secretion were studied. Proglumide and CR-1392 caused a rightward and parallel shift, respectively, in the dose-response curve of CCK8 stimulated pancreatic protein secretion in anesthetized rats, demonstrating a competitive-like mechanism of inhibition. The mean PA2 values, demonstrating the 50% inhibitory dose of proglumide and CR-1392 were 3.7 and 5.7, respectively; i.e., CR-1392 proved to be about 100 times more potent than proglumide. In conscious rats, protein output and the volume of pancreatic juice were significantly decreased for about 2 h in response to 150 mg/kg of proglumide or 3 mg/kg of CR-1392 administered s.c. during diversion of pancreatic juice, demonstrating inhibition of endogenous CCK by glutaramic acid derivatives. Indeed, during reintroduction of precollected pancreatic juice into the duodenum, when the release of CCK is known to be almost totally eliminated, pancreatic secretion was not significantly modified by the same doses.

Anesthesia↗
PubMed1987

Flow cytometric determination of the sperm cell number in diluted bull semen samples by DNA staining method.

Flow cytometric determination of the number of bull sperm cells showed that the number of spermatozoa measured by light scattering may considerably differ from the actual number of sperm cells in the samples, depending on the proportion of contaminating particles, similar in size to sperm cells. No accurate information can be obtained from the sum of live and dead cells distinguished by means of double fluorescence staining, since a part of the sperm cell population is in a transitory state i.e. between the viable and dead states, so it cannot be stained by either dye. The number of spermatozoa in the sample can be determined very accurately if the sample is treated first with Nonidet-P-40 detergent then stained with propidium iodide. With this procedure the DNA content of each cell nucleus can be labeled and, through detecting the fluorescence signals, the actual sperm cell count of the sample can be determined with the accuracy of 95-98%.

Animals↗
PubMed1986

Effects of somatostatin on basal and stimulated pancreatic secretion in conscious rat.

The effects of somatostatin on pancreatic secretion were studied in conscious rats during diversion and recirculation of pancreatic juice. Pancreatic secretion was significantly inhibited by low doses (2 micrograms/kg/h) of somatostatin during diversion of pancreatic juice. The inhibitory effect was more marked on bicarbonate and protein output than on volume, while in bicarbonate and protein output a rebound effect was observed. These data suggest a combined inhibitory effect of somatostatin on endogenous CCK release and cholinergic mechanisms. During recirculation of pancreatic juice there was no rebound effect, thus only the inhibition of cholinergic mechanisms seems to be involved in the inhibitory effect of somatostatin. During recirculation, CCK-OP-stimulated bicarbonate and protein secretion was strongly inhibited by somatostatin. Even water secretion not stimulated by CCK-OP was significantly inhibited demonstrating a supplementary inhibitory effect on basal cholinergic mechanisms. Somatostatin decreased only slightly the synthetic secretin-stimulated water and bicarbonate secretion. The more effective inhibition of protein output was explained by an additive effect of somatostatin on basal cholinergic tone.

Animals↗