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Modulation of thermal killing of bovine lymphocytes and preimplantation mouse embryos by alanine and taurine.
1992
Malayer J.R. | Pollard J.W. | Hansen P.J.
Addition of alanine and taurine blocked killing of lymphocytes caused by culture at 45 C. The optimal concentration for thermoprotection was achieved at 12.5 mM for L-alanine and 5 mM for taurine. Both D and L forms of alanine provided thermoprotection. The effect of these agents was not simply to increase osmolarity of the culture medium, because NaCl did not provide thermoprotection at comparable concentrations. Alanine and taurine were each tested at concentration of 50 mM for ability to block heat shock-induced killing and developmental retardation of 8- to 16-cell mouse embryos. Both agents enhanced embryo development after exposure to high temperature, though development remained less than that for embryos not exposed to high temperature. In one experiment, for example, 81% of embryos cultured at 38 C advanced in development during culture vs 0% at 42 C, 15% at 42 C with alanine, and 32% at 42 C with taurine. The beneficial effect of alanine at high temperature may have been partly attributable to effects independent of thermoprotection, because development of embryos cultured at 38 C was also improved by alanine.
Afficher plus [+] Moins [-]Clinicopathological studies on the subclinical fascioliasis in the Korean native cows in Chonnam area.
1989
Lee C.G. | Wee S.H. | Park S.J.
Fecal samples were taken from 402 cows in Posung, Chonnam which was designated as a place for Korean native cattle breeding. Prevalence of internal parasitisms were determined by the fecal examinations using the floatation and sedimentation procedures. 62.9 % of the cows were found as positive cases with excretion of the eggs of Fasciola hepatica in the fecal specimens. Of those infected with F. hepatica 97 cows free of other pathogenic intestinal parasites were chosen for albendazole treatment. Albendazole tablets (10mg/Kg) were administered to the cows twice at the interval of 4 weeks. Blood samples were collected via jugular vein prior to the first treatment, four weeks after the first treatment and four weeks after the second treatment, respectively. At the same time fecal samples were collected for parasitological examinations by sedimentation methods. The mean pretreatment count was 44 fluke eggs per gram of feces, which compared with 27 epg and 17 epg four weeks after the first and second treatment, respectively. Most of the hematological and biochemical values fluctuated within the normal ranges during the experiment. Eosinophil counts were high initially, decreased after the first treatment and thereafter remained steady. The opposite was the case with aspartate and alanine aminotransferases.
Afficher plus [+] Moins [-]Effect of bathing in a 0.1% aqueous solution of ethacridine lactate on selected physiological parameters of Cornu aspersum Müller edible snails
2020
Ziętek, Jerzy | Dzięgiel, Beata | Wójcik, Alicja | Wilczyńska, Anna | Adaszek, Łukasz | Winiarczyk, Stanisław
The prohibition of antibiotic use in edible snails obligates breeders to treat bacterial infections by different means, of which a common one is a bath in Gram-positive– and partially Gram-negative–bactericidal ethacridine lactate solution. The aim of the study was to determine the effect of bathing Cornu aspersum Müller snails in a 0.1% aqueous solution of ethacridine lactate on selected physiological parameters of haemolymph. The study included 80 snails, divided into two equal groups (study and control). The study group was subjected to bathing in ethacridine lactate and the control group to bathing in tap water. Both groups were treated daily for seven days. The number of haemocytes in the haemolymph, the activity of alanine (ALT) and aspartate (AST) aminotransferases, and the concentration of urea were determined. In the study group, after exposure to ethacridine lactate solution an increase in ALT activity, changes in the De Ritis ratio, an increase in the amount of haemocytes, and a decrease in body weight were found. No such changes were detected in the control group snails or in animals after the first bath. Multiple applications of a 0.1% ethacridine lactate bath may adversely affect Cornu aspersum Müller snails.
Afficher plus [+] Moins [-]Protective effects of bisoprolol against cadmium-induced myocardial toxicity through inhibition of oxidative stress and NF-κΒ signalling in rats
2021
Liu, Jinhua | Xie, Ying | Han, Zhujun | Wang, Hailong | Xu, Wenhu
The aim of the study was to investigate the mitigative effects of bisoprolol (BIS) in cadmium-induced myocardial toxicity on oxidative stress and its inhibitive effect on nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) signalling in rats. Male albino Wistar rats were assigned to control, Cd, BIS 2 (2 mg/kg b.w.) and BIS 8 (8 mg/kg b.w.) groups with nine rats in each. Over four weeks, the control group was administered 1% gum acacia, all other groups received 3mg/kg b.w. CdCl₂ dissolved in distilled water, and the BIS groups were additionally given bisoprolol in gum acacia. Blood samples were collected for biochemical estimations. Blood pressure and serum biomarker (lactate dehydrogenase, aspirate transaminase, alanine transferase and creatine kinase-MB, enzyme (superoxide dismutase, lipid hydroxy peroxidase, catalase and malondialdehyde), and tumour necrosis factor alpha (TNF-α) concentrations were measured. Western blot analysis was conducted for NF-κB and glutathione S-transferase (GST). After sacrificing the rats, cardiac tissue samples were examined histopathologically. Our findings pointed to a significant decrease (P < 0.05) in the studied serum biomarkers and levels of the relevant enzymes in the BIS 8 group compared to the Cd group. A significant decrease (P < 0.05) in NF-kB p65 expression and TNF-α levels was noted in the BIS 8 group relative to the BIS 2 and Cd groups, indicating a reduction at a higher dose. In microscopy, histopathological changes in the cardiac muscles of the BIS 8 group were evident compared to those of the Cd group. BIS seemed to have protective effects against cardiac injury induced by cadmium and could be considered a novel therapeutic drug and prognostic biomarker in the pathology of the many cardiovascular diseases caused by heavy metal intake.
Afficher plus [+] Moins [-]Regional variations and age-related changes detected with magnetic resonance spectroscopy in the brain of healthy dogs
2014
Objective-To investigate age-related and regional differences in estimated metabolite concentrations in the brain of healthy dogs by means of magnetic resonance spectroscopy (MRS). Animals-15 healthy Beagles. Procedures-Dogs were grouped according to age as young (n = 5; all dogs were 2 months old), adult (5; mean age, 4.5 years), or geriatric (5; all dogs were 12 years old). Imaging was performed by use of a 1.5-T MRI system with T1- and T2-weighted spin-echo and fluid-attenuated inversion recovery sequences. Signal intensity measurements for N-acetyl aspartate, creatine, choline, and lactate-alanine (the spectroscopic peaks associated with alanine and lactate could not be reliably differentiated) were determined with MRS, and areas under the spectroscopic peaks (representing concentration estimates) were calculated. Ratios of these metabolite values were compared among age groups and among brain regions with regression analysis. Results-The choline-to-creatine ratio was significantly higher in young dogs, compared with other age groups. The N-acetyl aspartate-to-choline ratio was significantly lower in young dogs and geriatric dogs than in adult dogs. When all age groups were considered, the choline-to-creatine ratio was significantly higher and N-acetyl aspartate-to-choline ratio was significantly lower in the frontal lobe than in all other regions. The N-acetyl aspartate-to-creatine ratio was significantly lower in the cerebellum than in other regions. Conclusions and Clinical Relevance-Metabolite ratios varied significantly among age groups and brain regions in healthy dogs. Future studies should evaluate absolute concentration differences in a larger number of dogs and assess clinical applications in dogs with neurologic diseases.
Afficher plus [+] Moins [-]Concentrations of amino acids in the plasma of neonatal foals with septicemia
1991
Zicker, S.C. | Spensley, M.S. | Rogers, Q.R. | Willits, N.H.
Concentrations of amino acids in the plasma of 13 neonatal foals with septicemia were compared with the concentrations of amino acids in the plasma of 13 age-matched neonatal foals without septicemia. Analysis of the results revealed significantly lower concentrations of arginine, citrulline, isoleucine, proline, threonine, and valine in the plasma of foals with septicemia. The ratio of the plasma concentrations of the branched chain amino acids (isoleucine, leucine, and valine) to the aromatic amino acids (phenylalanine and tyrosine), was also significantly lower in the foals with septicemia. In addition, the concentrations of alanine, glycine, and phenylalanine were significantly higher in the plasma of foals with septicemia. Therefore, neonatal foals with septicemia had significant differences in the concentrations of several amino acids in their plasma, compared with concentrations from healthy foals. These differences were compatible with protein calorie inadequacy and may be related to an alteration in the intake, production, use, or clearance of amino acids from the plasma pool in sepsis.
Afficher plus [+] Moins [-]Effects of superoxide dismutase on injury induced by anoxia and reoxygenation in equine small intestine in vitro
1991
Johnston, J.K. | Odoh, Bethrand Toochukwu | Gillette, D. | Soma, L.R.
Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxygenation; and (5) anoxia for 30 minutes. Anoxia reduced the accumulation of radiolabeled L-alanine and caused cell swelling, as indicated by an increase in tissue water and tissue Na contents. Reoxygenation improved the tissue's ability to accumulate L-alanine, but tissue swelling continued after this treatment. Tissue Na content and L-alanine accumulation were restored to control values by reoxygenation with superoxide dismutase in the bathing medium. The grade of structural damage, as indicated by separation of eptihelial cells from villi, was equally severe after all, but control, conditions. Superoxide dismutase had no effect on the tissue control conditions. Results of this study suggest that superoxide radicals are involved in the pathogenesis of reperfusion injury in equine jejunal mucosa and that this may be of clinical importance in cases of small intestinal strangulation obstruction.
Afficher plus [+] Moins [-]Modulation of thermal killing of bovine lymphocytes and preimplantation mouse embryos by alanine and taurine
1992
Malayer, J.R. | Pollard, J.W. | Hansen, P.J.
Addition of alanine and taurine blocked killing of lymphocytes caused by culture at 45 C. The optimal concentration for thermoprotection was achieved at 12.5 mM for L-alanine and 5 mM for taurine. Both D and L forms of alanine provided thermoprotection. The effect of these agents was not simply to increase osmolarity of the culture medium, because NaCl did not provide thermoprotection at comparable concentrations. Alanine and taurine were each tested at concentration of 50 mM for ability to block heat shock-induced killing and developmental retardation of 8- to 16-cell mouse embryos. Both agents enhanced embryo development after exposure to high temperature, though development remained less than that for embryos not exposed to high temperature. In one experiment, for example, 81% of embryos cultured at 38 C advanced in development during culture vs 0% at 42 C, 15% at 42 C with alanine, and 32% at 42 C with taurine. The beneficial effect of alanine at high temperature may have been partly attributable to effects independent of thermoprotection, because development of embryos cultured at 38 C was also improved by alanine.
Afficher plus [+] Moins [-]In vitro transport of L-alanine by equine cecal mucosa
1989
Odoh, Bethrand Toochukwu | Kleinzeller, A. | Donawick, W.J. | Topkis, V.A.
When sheets of mucosa from the cecum of clinically normal horses were incubated in vitro with radiolabeled L-alanine, they could accumulate this amino acid against an apparent concentration gradient after 60 to 150 minutes of incubation. The active transport system for L-alanine was on the serosal surface of the mucosal sheet only. L-Alanine accumulation at 60 minutes was partly inhibited by 20 mM glycine (P < 0.01), 0.5 mM ouabain (P < 0.05), and Na deprivation (P < 0.02). Anoxia for 60 minutes increased L-alanine accumulation, but had adverse effects on cell structure and intracellular cation distributions. Transmucosal fluxes induced a small, but significant (P < 0.05), net secretion of L-alanine, and the mean (+/- SEM) transmucosal potential difference was 7.3 +/- 0.7 mV over the period of flux measurement. It was concluded that L-alanine was accumulated by the serosal surface of the cecal mucosa, possibly to provide substrate for tissue metabolism. There was no evidence that the cecal mucosa could actively transport this amino acid from the luminal bathing medium.
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