ABSTRACT
1. This study was conducted to determine the effects of heat stress on fearfulness, leucocyte components, oxidative stress and lipid peroxidation in two commercial broiler strains, Cobb (C) and Ross (R). 2. At 36 and 37 d of age birds were exposed to 38 +/- 1 degree C for 3 h. Rectal temperatures, duration of tonic immobility (TI), haematocrit values, proportions of leucocyte components (heterophil, lymphocyte, basophil, eosinophil, monocyte), malondialdehyde (MDA) concentrations and antioxidant enzyme activities (CAT, SOD, GPx) of all the birds were determined, before and after heat treatment. 3. Rectal temperatures increased and haematocrit values decreased in birds exposed to heat stress. Heat stress caused a significant increase in heterophil/lymphocyte and in basophil ratios. 4. Exposing birds to heat stress increased duration of TI, suggesting heat-stressed birds tended to be more fearful. 5. Heat stress resulted in a significant Genotype x Treatment interaction for MDA concentration. CAT, SOD and GPx activities; MDA concentrations in heat-stressed R strain birds were greater than in heat-stressed C strain birds.
Subject(s)
Chickens/physiology , Lipid Peroxidation/physiology , Oxidative Stress/physiology , Poultry Diseases/physiopathology , Stress, Physiological/veterinary , Animals , Body Temperature , Catalase/blood , Glutathione Peroxidase/blood , Hematocrit , Hot Temperature , Leukocyte Count , Malondialdehyde/blood , Restraint, Physical , Stress, Physiological/physiopathology , Superoxide Dismutase/bloodABSTRACT
The ethanol and methanol extracts of Arbutus unedo leaves were screened for antioxidant activity. The antioxidant activity was determined by an improved assay based on the decolorization of the radical monocation of [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)] (ABTS). The ethanol and methanol extract of A. unedo leaves displayed potent antioxidant activity.
Subject(s)
Antioxidants/chemistry , Ericaceae , Phytotherapy , Plant Extracts/chemistry , Chromans , Humans , Plant LeavesABSTRACT
1. This study was conducted to determine metabolic and physiological responses of 2 commercial broiler strains, Hubbard (H) and Cobb (C), exposed to an ambient temperature of 38 degrees +/- 1 degree C for 2 h at 14 and 15 d of age. 2. Exposure to high temperature at an early age resulted in weight loss in strain C, which was not compensated for by 35 d of age but there was no weight loss in strain H. 3. Exposure of broilers to heat stress (38 degrees +/- 1 degree C) at 35 d of age resulted in an increase in rectal temperature, regardless of previously high temperature experience but acid-base balance and haematocrit values were not affected by heat stress. 4. Malondialdehyde concentration was higher in unexposed birds than in previously exposed ones and did not significantly differ between strains.
Subject(s)
Chickens/physiology , Heat Stress Disorders/veterinary , Hot Temperature/adverse effects , Poultry Diseases/physiopathology , Animals , Blood Gas Analysis/veterinary , Body Temperature , Body Weight , Chickens/growth & development , Chickens/metabolism , Heat Stress Disorders/physiopathology , Hematocrit/veterinary , Hydrogen-Ion Concentration , Malondialdehyde/analysis , Potassium/blood , Random Allocation , Seasons , Sodium/blood , TurkeyABSTRACT
In order to explore the possibility of supplanting the requirement of a 5'-triphosphate moiety for the activation of the 2-5A-dependent endonuclease (RNase L) of mouse L-cells, two new tetrameric analogues of 2-5A were synthesized. The first tetramer, obtained by both a modified prebiotic synthetic approach as well as a phosphite triester solid phase oligonucleotide synthesis method, was p5'A2'p5'A2'p5'(br8A)2'p5'(br8A). The second oligonucleotide was derived from the former by a sequence involving periodate oxidation, reaction with n-hexylamine, and cyanoborohydride reduction, resulting in conversion of the 2'-terminal adenosine residue to 9-(3'-aza-4'-hexyl-1',2',3',4'-tetradeoxyhexopyranos-1(1)-yl)-8-++ +bromoadenine. Both of these oligomers, bearing only 5'-monophosphate groups, were found to be as potent as 2-5A itself as activators of the RNase L of mouse L-cells.
Subject(s)
Adenine Nucleotides/chemical synthesis , Deoxyadenosines/chemical synthesis , Oligoribonucleotides/chemical synthesis , Protein Synthesis Inhibitors/pharmacology , Ribonucleases/metabolism , Adenine Nucleotides/metabolism , Adenine Nucleotides/pharmacology , Animals , Deoxyadenosines/metabolism , Deoxyadenosines/pharmacology , Enzyme Activation/drug effects , Mice , Oligoribonucleotides/metabolism , Oligoribonucleotides/pharmacologyABSTRACT
The oligonucleotide ppp5'A2'p5'A2'p5'A, known as 2-5A, is a potent translational inhibitor involved in some aspects of interferon action. To explore the specific function of the charged 5'-triphosphate moiety, we prepared a series of congeners in which the 5' region was hypermodified. Thus, uronic acid derivatives were substituted for the 5' terminal adenosine residue of 2-5A. Compounds 9, 10, 11 and 12 carried adenosine 5'-uronic acid, ethyl adenosine 5'-uronate, adenosine 5'-uronamide, and adenosine 5'-(N-ethyl)uronamide, respectively, in place of the 5' terminal adenosine triphosphate moiety of 2-5A. While all the analogues showed some weak interaction with the 2-5A-dependent endonuclease (RNase L), compound 9 showed the strongest binding ability, and while unable to activate the mouse RNase L, could activate human RNase at a concentration 100-fold greater than that required for the parent 2-5A. This result suggests that the function of the 5'(poly)phosphate moiety of 2-5A may be fulfilled by some other anionic moiety.
Subject(s)
Adenine Nucleotides/chemical synthesis , Oligonucleotides/chemical synthesis , Oligoribonucleotides/chemical synthesis , Protein Synthesis Inhibitors/chemical synthesis , Uronic Acids/chemical synthesis , Adenine Nucleotides/pharmacology , Animals , Cell Line , Endoribonucleases/metabolism , Humans , Liver/drug effects , Liver/enzymology , Lymphoid Tissue/cytology , Lymphoid Tissue/drug effects , Lymphoid Tissue/enzymology , Mice , Oligonucleotides/pharmacology , Oligoribonucleotides/pharmacology , Protein Synthesis Inhibitors/pharmacology , Uronic Acids/pharmacologyABSTRACT
8-Methyladenosine-substituted analogues of 2-5A, p5'A2'p5'A2'p5'(me8A), p5'A2'p5'(me8A)2'p5'(me8A), p5'(me8A)2'p5'(me8A)2'p5'(me8A), and p5'(me8A) 2'p5'A2'p5'A, were prepared via a modification of a lead ion-catalyzed ligation reaction. These 2-5A monophosphates were converted into the corresponding 5'-triphosphates. Substitution of an 8-methyladenosine residue at the third position (2'-terminus) of the oligonucleotides increased the stability to snake venom phosphodiesterase digestion. Both binding and activation of mouse liver 2-5A dependent ribonuclease (RNase L) by the various 8-methyladenosine-substituted 2-5A analogues were examined. Among the 8-methyladenosine-substituted trimer analogues, the analogues with 8-methyladenosine residing in the 2'-terminal position showed the strongest binding affinity and were several times more effective than 2-5A itself as an inhibitor of translation.
Subject(s)
Adenine Nucleotides/metabolism , Adenosine/analogs & derivatives , Oligoribonucleotides/metabolism , Protein Biosynthesis/physiology , RNA/metabolism , Adenine Nucleotides/chemical synthesis , Adenine Nucleotides/chemistry , Adenosine/chemistry , Animals , Endoribonucleases/metabolism , Kinetics , Liver Extracts , Magnetic Resonance Spectroscopy , Methylation , Oligoribonucleotides/chemical synthesis , Oligoribonucleotides/chemistry , Phosphodiesterase I , Phosphoric Diester Hydrolases/metabolism , RatsABSTRACT
In this study the activity of a membrane-bound enzyme, gamma-glutamyl transferase GGT (gamma-glutamyl transpeptidase - GGTP), was investigated in the peripheral blood lymphocytes (PBL) from patients with Behçet's disease. Lymphocyte GGT activity in Behçet's disease was found to be significantly lower than that of control lymphocytes (p less than 0.01). This altered activity may be due to the abnormality in the membrane of lymphocytes of Behçet's disease patients.
