bluuebunny/crossref_metadata_2025_split huggingface dataset:
α1‐acid glycoprotein and serum binding of drugs in healthy and diseased dogs
Authors: BELPAIRE F. M. , RICK A. DE , DELLO C. , FRAEYMAN N. , BOGAERT M. G. 
Published: April 2008

Belpaire, F.M., De Rick, A., Dello, C., Fraeyman, N. & Bogaert, M.G. apacid glycoprotein and serum binding of drugs in healthy and diseased dogs. J. vet. Pharmacol. Therap. 10, 43–48.Inter‐individual variation in drug serum protein binding was studied in healthy dogs and in dogs with inflammatory diseases for lidocaine, oxprenolol and propranolol, which bind mainly to α1‐acid glycoprotein (α1‐AGP), and for diazepam, digitoxin and phenytoin, which bind mainly to albumin. For the drugs mostly bound to α1‐AGP, in both groups of dogs binding varied considerably, and it was markedly higher in dogs with inflammatory disease. For the other drugs, the variation in binding was smaller and did not differ between the two groups of dogs. In both groups of dogs, the α1‐AGP concentration varied widely; it was higher in the serum of the dogs with inflammation, while the concentration of albumin was lower in these animals. There was a significant negative correlation between percentage free lidocaine, oxprenolol or propranolol and α1‐AGP concentration, suggesting that the inter‐individual variation in binding of these drugs is due to the variation in α1‐AGP concentration. There was a marked intra‐individual variation in lidocaine binding and in serum α1‐AGP concentration, studied over a period of 3 weeks in healthy dogs; a significant negative correlation between percentage free lidocaine and α1‐AGP concentration was obtained.
Pharmacokinetics of oxfendazole in goats: a comparison with sheep
Authors: BOGAN J. , BENOIT E. , DELATOUR P. 
Published: April 2008

Bogan, J., Benoit, E. & Delatour, P. Pharmacokinetics of oxfendazole in goats: a comparison with sheep. J. vet. Pharmacol. Therap. 10, 305–309.In goats, there was a linear correlation of area under the plasma concentration–time curve (AUC) with dose in the range 0–20 mg/kg as single dosages of oxfendazole (OFZ). The bioavailability of OFZ after oral administration was lower in goats than in sheep. The repetition of three administrations at 24 h intervals produced significant increase in the AUC in comparison with a single administration equivalent to the total dosage (1 × 5.0 and 3 × 1.7 mg/kg). Infection with O. circumcincta produced a 33% decrease in the bioavailability of OFZ.
Colonic α2‐adrenoceptor‐mediated responses in the pony
Authors: ROGER T. , RUCKEBUSCH Y. 
Published: April 2008

Roger, T. & Ruckebusch, Y. Colonic α2‐adrenoceptor‐mediated responses in the pony. J. vet. Pharmacol. Therap. 10, 310–318.The motor responses of the caecum and colon to stimulation of α2‐adrenoceptors by xylazine and detomidine at the recommended dose levels of 0.6 and 0.1 mg/kg were investigated in three ponies. The motor changes of the left ventral colon induced by continuous intra‐arterial infusion of a prostaglandin (PGF2α) were used to assess the relative inhibitory effects of xylazine and detomidine in a colic model. The administration of α2‐agonists inhibited the spiking activity on the whole of the large intestine for 20–30 min (xylazine) or 2–3 h (detomidine). However, the detomidine‐induced inhibition was preceded by a short period of increased smooth muscle basal tone as indicated by strain‐gauge force transducer measurements. This pattern of activity was neither reversed nor prevented by the administration of tolazoline (10 μg/kg/min) intra‐arterially. In contrast, inhibition of the colonic phasic and tonic motor activity by α‐adrenoceptor stimulation was reversed competitively by tolazoline. The intra‐arterial infusion of prostaglandin F2α (10 μg/kg/min) induced prolonged and sustained spiking activity that might be related to signs of mild colic. Detomidine, and to a lesser extent xylazine, relaxed the whole of the large intestine and this was accompanied by alleviation of the signs of visceral pain.
Dose‐dependent plasma elimination of subcutaneously administered calcium heparin in horses
Authors: GERHARDS H. , KIETZMANN M. 
Published: April 2008

Gerhards, H., & Kietzmann, M. Dose‐dependent plasma elimination of subcutaneously administered calcium heparin in horses.J. vet. Pharmacol. Therap.11, 77–83.Pharmacokinetic parameters for subcutaneous low dose heparin in horses have been determined. Four groups of five and one group of eleven mature, healthy horses of various breeds were given single subcutaneous injections of 60, 80, 100, 125, and 150 units of calcium heparin/kg of body weight (U/kg) in the pectoral region. Jugular blood samples were collected prior to, and at hourly intervals for 12 h after injection. Heparin plasma concentrations were measured using a commercially available amidolytic assay. Peak concentrations 4 h after administration were 0.021 ± 0.016 (mean ± SD) units of heparin/ml of plasma (U/ml) after 60 U/kg, 0.035 ± 0.025 U/ml after 80 U/kg, 0.023 ± 0.004 U/ml after 100 U/kg, 0.034 ±0.019 U/ml after 125 U/kg, and 0.053 ±0.019 U/ml after 150 U/kg. Data from groups given 60 and 100 U/kg could not be used for kinetic calculations. Elimination constant (1/h), elimination half‐life (h), and elimination time (h) calculated to reach base‐line values after 80 U/kg were 0.182 ± 0.041 1/h, 3.8 ± 0.9 h, and 9.7 + 2.2 h. After 125 U/kg, corresponding values were 0.211 ± 0.019 1/h, 3.3 ± 0.3 h, 13.4 ± 1.2 h, and after 150 U/kg 0.098 ± 0.015 1/h, 7.1 ± 1.1 h, and 20.6 ± 3.2 h. Calculated heparin concentrations 12 h after administration of 80, 125, and 150 U/kg were 0.011 ± 0.002, 0.010 ± 0.001, and 0.027 ± 0.004 U/ml. After seven successive injections of 150 U/kg at 12 h intervals in one horse, the elimination constant decreased from 0.23/h after the first to 0.08/h after the seventh injection, and the elimination time increased from 10 h to 40 h. Reducing the dosage from 150 U/kg initially to 125 U/kg for six successive injections reduced the prolonged elimination after repeated injections.
Zearanol metabolism by subcellular fractions from lamb liver
Authors: POMPA G. , MONTESISSA C. , LAURO F. M. DI , FADINI L. , CAPUA C. 
Published: April 2008

Pompa, G., Montesissa, C., Di Lauro, F.M., Fadini, L. & Capua, C. Zearanol metabolism by subcellular fractions from lamb liver.J, vet. Pharmacol. Therap. 11, 197–203.Zearanol (7‐α‐zearalanol or α‐ZAL) metabolism in vitro by subcellular fractions (microsome and cytosol) from lamb livers was investigated. The use of a high performance liquid chromatography (HPLC) technique capable of resolving epimers, revealed that when nicotinamide adenine dinucleotide (NAD) was added as a co‐factor to metabolic mixtures, the oxidized form, zearalanone (ZAN) was the major metabolite, although a small amount of 7‐β‐zearalanol (β‐ZAL) was also produced. In order to confirm β‐ZAL as a product of ZAN reduction, the metabolism of the latter, by microsome and cytosol in the presence of NADH as co‐factor, was investigated. The results obtained revealed that both α‐ZAL and β‐ZAL were present at the end of the incubation, the former at a higher concentration than the latter. When NAD and NADH were added as co‐factors to incubation mixtures containing α‐ZAL, the production of β‐ZAL was increased as a consequence of the higher ZAN reduction in the presence of the reducing co‐factor. Nevertheless, ZAN remained the major metabolite produced from α‐ZAL by both the subcellular fractions investigated.
Pharmacokinetics, metabolism and renal clearance of flumequine in veal calves
Authors: MEVIUS D.J. , BREUKINK H.J. , GUELEN P. J. M. , JANSEN T. , De GRÈVE B. 
Published: April 2008

Mevius, D.J., Breukink, H.J., Guelen, P.J.M., Jansen, T. & de Grève, B. Pharmacokinetics, metabolism and renal clearance of flumequine in veal calves. J. vet. Pharmacol. Therap. 13, 159–169.The pharmacokinetics of flumequine was studied in 1‐, 5‐and 18‐week‐old veal calves. A two‐compartment model was used to fit the plasma concentration‐time curve of flumequine after the intravenous injection of 10 mg/kg of a 10% solution. The elimination half‐life (t1/2 ß) of the drug ranged from 6 to 7 h. The Vd ß and ClB of 1‐week‐old calves (1.07 1/kg, 1.78 ml/min/kg) were significantly lower than those of 5‐week‐old (1.89 1/kg, 3.23 ml/min/kg) and 18‐week‐old calves (1.57 1/kg, 3.10 ml/min/kg). After the oral administration of 10 mg/kg of a 2% flumequine formulation mixed with milk replacer, the Cmax was highest in 1‐week‐old (9.27 μg/ml) and lowest in 18‐week‐old calves (4.47 μg/ml). The absorption was rapid (Tmax of approximately 3 h) and complete. When flumequine itself and a formulation containing 2% flumequine and 20 times 106 iu of colistin sulphate were mixed with milk replacer and administered at the same dose rate, absorption was incomplete and Cmax was lower. The main urinary metabolite of flumequine was the glucuronide conjugate (approximately 40% recovery within 48 h of intravenous injection) and the second most important metabolite was 7‐hydroxy‐flumequine (approximately 3% recovery within 12 h of intravenous injection). Only 3.2–6.5% was excreted in the urine unchanged. After oral administration a ‘first‐pass’ effect was observed, with a significant increase in the excretion of conjugated drug. For 1‐week‐old calves it is recommended that the 2% formulation should be administered at a dose rate of 8 mg/kg every 24 h or 4 mg/kg every 12 h; for calves over 6 weeks old, the dose should be increased to 15 mg/kg every 24 h or 7.5 mg/kg every 12 h. The formulation containing colistin sulphate should be administered to 1‐week‐old calves at a flumequine dose of 12 mg/kg every 24 h or 6 mg/kg every 12 h. Dr D. J. Mevius, Department of Large Animal Medicine and Nutrition, Yalelaan 16, 3508 TD Utrecht, the Netherlands.
The effects of dexamethasone, betamethasone, flunixin and phenylbutazone on bovine naturalkiller‐cell cytotoxicity
Authors: O'BRIEN M. A. , DUFFUS W. P. H. 
Published: April 2008

O'Brien, M.A. & Duffus, W.P.H. The effects of dexamethasone, betamethasone, flunixin and phenylbutazone on bovine natural‐killer‐cell cytotoxicity. J. vet. Pharmacol. Therap, 13, 292–297.A series of in‐vitro experiments was performed utilizing the ability of bovine peripheral‐blood mononuclear cells (PBMC) to induce lysis of Madin‐Darby bovine kidney (MDBK) cells infected with bovine herpesvirus 1 (BHV1), in an antibody‐independent natural‐killer(NK)‐cell cytotoxic assay. The effects of dexamethasone (dexamethasone sodium phosphate), betamethasone (betamethasone sodium phosphate), flunixin (flunixin meglumine) and phenylbutazone on this NK cytolysis were studied using concentrations of the drugs ranging from well below to well above those normally attained in plasma at recommended therapeutic doses. All four drugs inhibited NK activity. For each agent a minimum inhibitory concentration (MIC50) required to inhibit NK activity by approximately 50% was calculated. For dexamethasone, betamethasone and flunixin the MIC50 was lower after a 24‐h pre‐incubation of PBMC with each drug, although a marked inhibition was seen when the drug was only present during the 5‐h NK assay itself. In contrast the MIC50 for phenylbutazone rose after a 24‐h pre‐incubation with PBMC. Dr W. P. H. Duffus, Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 OES, UK.
Influence of feeding on the bioavailability of ronidazole prolonged‐release formulations in pigeons
Authors: BAERT L. , HERMAN J. , REMON J. P. 
Published: April 2008

Baert, L., Herman, J. & Remon, J.P. Influence of feeding on the bioavailability of ronidazole prolonged‐release formulations in pigeons. J. vet. Pharmacol Therap. 13, 304–308.The influence of feeding on the bioavailability of ronidazole (5 mg per animal) formulated as a hydrophilic‐matrix tablet or as lipophilic pellets, was evaluated in pigeons. Administered to fed pigeons, prolonged drug absorption was obtained for both formulations. In non‐fed pigeons an immediate grinding of the formulations in the gizzard resulted in rapid drug absorption. This indicates that prolonged residence of the prolonged‐release formulations in the crop obtained in the fed condition seemed the only possible means of obtaining prolonged drug release in pigeons. J. P. Remon, Laboratory of Pharmaceutical Technology, State University of Gent, Harelbekestraat 72, B‐9000 Gent, Belgium.
The development of drug‐metabolizing enzymes in female sheep livers
Authors: KADDOURI M. , LARRIEU G. , EECKHOUTTE C. , GALTIER P. 
Published: April 2008

Kaddouri, M., Larrieu, G., Eeckhoutte, C. & Galtier, P. The development of drug‐metabolizing enzymes in female sheep livers. J. vet. Pharmacol. Therap. 13, 340–349.The purpose of this investigation was to determine age‐related changes of some hepatic drug‐metabolizing activities in Lacaune ewes in the foetal, neonatal (1 and 4 weeks), growing (7 months), pregnant (11 months) and adult (6 years) stages. Although microsomal cytochrome P‐450 was not detected in 3‐month‐old foetuses, it increased regularly from 1‐week‐to 11‐month‐old animals. Among mixed‐function oxidases, the development of aminopyrine and ethylmorphine N‐demethylases, benzo(α)pyrene hydroxylase and ethoxycoumarin O‐deethylase were correlated to that of total cytochrome P‐450. Due to their presence in foetal liver or their more rapid evolution, cytochrome b5, NADPH cytochrone c reductase, aniline hydroxylase, benzphetamine N‐demethylase and erythromycin N‐demethylase did not parallel the ontogenesis of cytochrome P‐450. Hepatic transferases showed different developmental patterns from mono‐oxygenases, so UDP glucuronyltransferase was detected in the foetus, reached maximum activity in all young ages up to the pregnant stage and subsequently fell in adult ewes. Concerning glutathione S‐transferase accepting l‐chloro‐2,4‐dinitrobenzene as substrate, similar values were obtained in the foetus and all young animals, whereas five‐to tenfold higher values were obtained in both pregnant and adult female sheep. N‐acetyltransferase using sulphamethazine did not significantly change from foetuses to adults but there were large differences in the capacity of hepatic acetylation between animals belonging to the same group. P. Galtier, Laboratoire de Pharmacologie‐Toxicologie, INRA, 180 chemin de Tournefeuille, BP 3, 31931 Toulouse, France.
Biliary secretion and enterohepatic recycling of fenbendazole metabolites in sheep
Authors: HENNESSY D. R. , STEEL J. W. , PRICHARD R. K. 
Published: April 2008

Fenbendazole (FBZ) was administered intraruminally at 5.0 mg/kg, containing a trace of [14C]‐FBZ, to sheep fitted with a permanent bile duct cannula and the behaviour of FBZ and its metabolites examined in bile and plasma. Of the administered radiolabeled dose, 47% was secreted in bile of which 34% was accounted for as conjugated and 4% as unconjugated (free) metabolites. Hydroxylated oxfendazole (OH.OFZ) was the major biliary metabolite contributing 66%, and hydroxy‐FBZ (OH.FBZ) 27%, of the total metabolites characterized. Small amounts of OFZ and hydroxy FBZ sulphone (OH. FBZ.SO2) were also present in bile. The rapid appearance of OH.OFZ in bile, even before maximum concentrations of OFZ occurred in plasma, indicated that sulphoxidation and hydroxylation was the major route of FBZ metabolism.Following intraduodenal infusion of free biliary metabolites, FBZ and its metabolites rapidly appeared in bile indicating absorption from the small intestine. When conjugated metabolites were infused they continued to appear in bile for a further 15–20 h after cessation of infusion indicating that absorption of hydroxylated metabolites occurred largely after bacterial deconjugation in the large intestine. Approximately 40% of biliary metabolites were estimated to undergo enterohepatic reabsorption but they contributed minimally to the metabolite content in plasma. It is suggested that during the process of recycling, biliary metabolites make substantial contact with parasites in the mucosa of the small and large intestine thereby contributing to the anthelmintic activity of FBZ.
Three phase elimination of oxytetracycline in veal calves; the presence of an extended terminal elimination phase
Authors: MEIJER L. A. , CEYSSENS K. G. F. , DEJONG W. TH. , GREVE B. I.J. A. C. DE 
Published: April 2008

The pharmacokinetics of oxytetracycline were studied after both intravenous (i.v.) and intramuscular (i.m.) administration to a group of five veal calves. Blood samples were taken frequently during the terminal elimination phase in order to calculate a reliable elimination rate constant. Because of the low limit of quantification of the method of analysis used, oxytetracycline plasma concentrations could be monitored over a 12‐day period of time.After the intravenous administration of oxytetracycline, data were fitted according a three‐compartment model. After i.m. administration, plasma‐concentration‐time curves could best be described by a two‐compartment model. It was demonstrated that a very slow terminal elimination phase was present both after i.v. and i.m. administration with a half‐life of approximately 95 h. The data show that this phase cannot be explained by slow absorption from the injection site and that release of oxytetracycline incorporated into bone is not a likely explanation.
A conservation paradox for the 21st century: the European wild rabbitOryctolagus cuniculus, an invasive alien and an endangered native species
Authors: LEES ALEXANDER C. , BELL DIANA J. 
Published: April 2008

ABSTRACTThis review highlights the status of the European wild rabbitOryctolagus cuniculus, which is threatened within its native range and yet is a highly successful colonizer across its worldwide, introduced range.The European wild rabbit is a keystone species in Iberia, and the survival of a range of threatened predator species, including the Iberian lynxLynx pardinusand Spanish imperial eagleAquila aldabertii, is dependent upon the restoration of rabbit populations. Although not native to the UK, the rabbit also performs significant ecosystem services for nationally rare UK species, by maintaining short sward heights in heathland and grassland ecosystems, and serving as a prey item for populations of predators.We identify the European wild rabbit as an excellent model to demonstrate the wide range of complex effects that an introduced mammalian species may exert on ecosystems to which it has been introduced. These effects include habitat degradation following overgrazing, competition with native mammals and facilitating meso‐predator release and hyperpredation.We also show that rabbit eradication from some sites may generate more problems than are solved because of the impacts of trophic cascades stemming from dependence on rabbits by native predator assemblages.
Structure and rheology of lithosphere in Italy and surrounding
Authors: Panza G. F. , Raykova R. B. 
Published: April 2008

AbstractWe define the structure and rheology of the lithosphere in Italy and surrounding, combining the cellular velocity models derived from nonlinear tomographic inversion with the distribution vs. depth of hypocentres to assess the brittle properties of the Earth’s crust. We average, over cells sized 1 × 1 degree, the mechanical properties of the uppermost 60 km of the Earth, along with seismicity, grouping hypocentral depths in 4‐km intervals. For most of the cells, the earthquake energy is concentrated in the upper crust (4–12 km). For some regions, where orogenic processes occur, the release of earthquake energy is shallower and limited to the uppermost 10 km of the crust. Ambiguities in the structural models are minimized considering the hypocentral distribution, mainly to define the location of the Moho boundary, when its identification, based on shear‐wave velocities, is not straightforward.
Inter‐dependence of dimerization and organelle binding in myosin XI
Authors: Li Jian‐Feng , Nebenführ Andreas 
Published: April 2008

SummaryCytoplasmic streaming is a ubiquitous process in plant cells that is thought to be driven by the active movement of myosin XI motor proteins along actin filaments. These myosin motors bind to organelles through their C‐terminal globular tail domain, although recent studies have also suggested a role for the central coiled‐coil region during organelle binding. Here we have investigated the relationship between these two protein domains of MYA1, an Arabidopsis myosin XI, in a series of in vivo experiments demonstrating that dimerization of the coiled‐coil region stabilizes organelle binding of the globular tail. Surprisingly, yeast two‐hybrid assays, bimolecular fluorescence complementation, Förster resonance energy transfer and in vitro pull‐down experiments all demonstrated that dimerization of the 174‐residue MYA1 coiled coils by themselves was unstable. Furthermore, only the first of the two major coiled‐coil segments in MYA1 contributed significantly to dimer formation. Interestingly, dimerization of myosin tail constructs that included the organelle‐binding globular tail was stable, although the globular tails by themselves did not interact. This suggests an inter‐dependent relationship between dimerization and organelle binding in myosin XI, whereby each process synergistically stimulates the other.
Deletion of the chloroplast‐localized AtTerC gene product in Arabidopsis thaliana leads to loss of the thylakoid membrane and to seedling lethality
Authors: Kwon Kwang‐Chul , Cho Myeon Haeng 
Published: April 2008

SummaryEarly seedling development in plants depends on the biogenesis of chloroplasts from proplastids, accompanied by the formation of thylakoid membranes. An Arabidopsis thaliana gene, AtTerC, whose gene product shares sequence similarity with bacterial tellurite resistance C (TerC), is shown to be involved in a critical step required for the normal organization of prothylakoids and transition into mature thylakoid stacks. The AtTerC gene encodes an integral membrane protein, which contains eight putative transmembrane helices, localized in the thylakoid of the chloroplast, as shown by localization of an AtTerC–GFP fusion product in protoplasts and by immunoblot analysis of subfractions of chloroplasts. T‐DNA insertional mutation of AtTerC resulted in a pigment‐deficient and seedling‐lethal phenotype under normal light conditions. Transmission electron microscopic analysis revealed that mutant etioplasts had normal prolamellar bodies (PLBs), although the prothylakoids had ring‐like shapes surrounding the PLBs. In addition, the ultrastructures of mutant chloroplasts lacked thylakoids, did not have grana stacks, and showed numerous globular structures of varying sizes. Also, the accumulation of thylakoid membrane proteins was severely defective in this mutant. These results suggest that the AtTerC protein plays a crucial role in prothylakoid membrane biogenesis and thylakoid formation in early chloroplast development.
Do consecutive flower visits within a crown diminish fruit set in mass‐flowering Hancornia speciosa (Apocynaceae)?
Authors: Pinto C. E. , Oliveira R. , Schlindwein C. 
Published: April 2008

Abstract Hancornia speciosa is a self‐incompatible, mass‐flowering, sphingophilous fruit crop (mangaba) of northeast and central Brazil. The flowers have a precise pollination apparatus, which optimizes pollen transfer between flower and pollinator. While the pollination mechanism avoids self‐pollination, mass‐flowering promotes geitonogamy. During a flower visit, almost half of the exogenous pollen grains adhering to the proboscis are deposited on the stigma surface. A pollination experiment with a nylon thread simulating six consecutive flower visits within a crown revealed that only the first two flowers visited (positions 1 and 2) are highly likely to set fruit. Super‐production of flowers, and consequently obligate low fruit set, seem to be part of the reproductive strategy of the obligate outcrossing plant, Hancornia speciosa.