bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacokinetics of clindamycin HCl administered intravenously, intramuscularly and subcutaneously to dogs
Authors: Lavy  , Ziv  , Shem‐Tov  , Glickman  , Dey  
Published: March 2003

A buffered aqueous solution of clindamycin Hcl (200 mg/mL) was injected intravenously (i.v.) intramuscularly (i.m.) and subcutaneously (s.c.) in a non‐randomized, partial cross‐over trial involving six male and six female dogs. Blood samples were collected at conventional, predetermined time periods and serum drug concentrations were determined by microbiological assay. Dogs were observed clinically for signs of pain, and activity of serum creatine phosphokinase (CPK) was monitored after i.m. dosing.The i.v. data from five of the dogs best fitted a two‐compartment open‐system pharmacokinetic model whereas a non‐compartment model was most suitable for analysis of the data from the remaining seven dogs. The mean i.v. elimination half‐life (t½β) and the mean residence time (MRT) were 124 and 143 min, respectively. The mean volume of distribution at steady state (Vss) was 0.86 L/kg. Little pain was recorded upon i.m. injection; mean peak serum drug concentration (Cmax) was 4.4 μg/mL, the elimination half‐life (t½el) was 247 min and the calculated bioavailability (F) was 115% of the i.v dose. Serum CPK activity was elevated to 25‐fold the pretreatment level in samples collected 4, 8 and 12 h after i.m. injection. Pain was not recorded after s.c. drug administration; the meanCmaxof 20.8 μg/mL was significantly greater than the corresponding value for the i.m. route, andFwas 310%. The s.c. route appears to be superior to the i.m. route in terms of local tolerance and serum drug level; a 10 mg/kg SID treatment regimen is suggested for treatment of canine infections due to clindamycin sensitive bacteria.
Differential inhibition of equine neutrophil function by phosphodiesterase inhibitors
Authors: Rickards K. J. , Page C. P. , Lees P. , Cunningham F. M. 
Published: March 2003

Rickards, K. J., Page, C. P., Lees, P., Cunningham, F. M. Differential inhibition of equine neutrophil function by phosphodiesterase inhibitorsJ. vet. Pharmacol. Therap.24,275–281.Neutrophils are recruited to the lungs of horses with chronic obstructive pulmonary disease (COPD) and exhibit increased activity after antigen challenge, which may contribute to inflammation and lung damage. Inhibition of phosphodiesterase isoenzymes (PDEs) has been shown to attenuate human neutrophil functions including superoxide production, leukotriene (LT)B4biosynthesis, enzyme and chemokine release. As equine neutrophils contain predominantly the isoenzyme, PDE4, the present study was undertaken to investigate the effects of rolipram, a PDE4 inhibitor, on equine neutrophil function. For comparison, the effects of the nonselective PDE inhibitor, theophylline, were examined. Cells from both normal horses and COPD horses in remission were used. Superoxide production was significantly inhibited by both rolipram [32.2 ± 2.6 vs. 10.1 ± 1.1 nmol/106cells and 49.8 ± 6.8 vs. 22.7 ± 2.2 nmol/106cells for normal and COPD susceptible horses, respectively, in response to 10–7 Mhuman recombinant (hr) C5a] and theophylline (19.0 ± 0.6 vs. 10.2 ± 0.6 nmol/106cells and 24.3 ± 2.1 vs. 10.7 ± 0.9 nmol/106cells for normal and COPD susceptible horses, respectively, in response to 10–7 MC5a). However, superoxide production induced by serum treated zymosan was inhibited only by theophylline (10–3 M). Neither hrC5a‐ nor platelet activating factor (PAF)‐induced neutrophil adherence to fibronectin coated plastic was reduced by rolipram (10–5 M). These results demonstrate that the effects of PDE inhibitors on equine neutrophils are both stimulus and function dependent. The PDE4 inhibitors may reduce neutrophil activationin vivoin horses with COPD.
Pharmacokinetics and pharmacokinetic/pharmacodynamic integration of marbofloxacin in calf serum, exudate and transudate
Authors: ALIABADI F. SHOJAEE , LEES P. 
Published: March 2003

Aliabadi, F. S., Lees, P. Pharmacokinetics and pharmacokinetic/pharmacodynamic integration of marbofloxacin in calf serum, exudate and transudate.J. vet. Pharmacol. Therap.25,161–174.Marbofloxacin is a fluoroquinolone antimicrobial drug used in cattle for the treatment of respiratory infections. In this investigation the pharmacokinetics (PK) of marbofloxacin were determined after intravenous and intramuscular dosing at a dosage of 2 mg/kg. In addition theex vivopharmacodynamics (PD) of the drug were determined in serum and three types of tissue cage fluid (transudate, inflammatory exudate generated by carrageenan and exudate generated by lipopolysaccharide). Marbofloxacin PK was characterized by a high volume of distribution after dosing by both routes (1.28 L/kg intravenous and 1.25 L/kg intramuscular). Corresponding area under the concentration–time curve (AUC) and elimination half‐life (t½el) values were 9.99 and 10.11 μg h/mL and 4.23 and 4.33 h, respectively. Values ofAUCfor carrageenan‐induced exudate, lipopolysaccharide‐induced exudate and transudate were, respectively, 8.28, 7.83 and 7.75 μg h/mL after intravenous and 8.84, 8.53 and 8.52 μg h/mL after intramuscular dosing. Maximum concentration (Cmax) values were similar for the three tissue cage fluids after intravenous and intramuscular dosing. Forin vivoPK data values ofAUC:minimum inhibitory concentration (MIC) (AUIC) ratio for serum were 250 and 253, respectively, after intravenous and intramuscular dosing of marbofloxacin against a pathogenic strain ofMannheimia haemolytica(MIC=0.04 μg/mL). For all tissue cage fluidsAUICvalues were >194 and >213 after intravenous and intramuscular dosing, andCmax/MICratios were 9 or greater, indicating a likely high level of effectiveness in clinical infections caused byM. haemolyticaofMIC0.04 μg/mL or less. This was confirmed by bothin vitro(serum) andex vivo(serum, exudate and transudate) measurements, which demonstrated a concentration‐dependent killing profile for marbofloxacin againstM. haemolytica. Ex vivo, after 24‐h incubation, virtually all bacteria were killed (<10 cfu/mL) in all samples collected up to 9 h (serum), 24 h (carrageenan‐induced exudate and transudate) and 36 h (lipopolysaccharide‐induced exudate). Application of the sigmoidEmaxequation to theex vivoantibacterial data provided, for serum,AUIC24 hvalues of 37.1 for bacteriostasis, 46.3 for bactericidal activity and 119.6 for elimination of bacteria. These data may be used as a rational basis for setting dosing schedules which optimize clinical efficacy and minimize the opportunities for emergence of resistant organisms.
Autocorrelated data in telemetry studies: time to independence and the problem of behavioural effects
Authors: Rooney S. M. , Wolfe A. , Hayden T. J. 
Published: March 2003

AbstractIndependence of locational fixes, to reduce the effects of autocorrelation, is often deemed a prerequisite for estimation of home range size and utilization when using data derived from telemetric studies. Three methods of estimating times to independence using movement estimates, along with a statistical method of estimating the level of autocorrelation of locational data, were examined for two species of mammal. Attempts to achieve statistically independent data by subsampling resulted in severe redundancy in the data and significant underestimation of range size and rates of movement. Even a sample interval of one fix per week did not guarantee independence and also resulted in underestimation of range size despite range asymptotes being reached. It would appear that the correct strategy for the best possible estimation of range size and use from telemetry would be the repeated use of as short a sampling interval as is possible over an extended period of time. Statistical methods to measure levels of autocorrelation in locational data may be useful for comparing rates of range use between different populations of the same species or between species, as long as the same sample interval is used.
The origins and character of ‘aboriginal subsistence’ whaling: a global review
Authors: REEVES RANDALL R. 
Published: March 2003

ABSTRACTThe International Whaling Commission (IWC) recognizes aboriginal subsistence whaling to be distinct from commercial whaling, and these two broad categories of whaling are subject to different management approaches. This paper describes recent, ongoing and likely future whale hunts that qualify, or may qualify, for aboriginal subsistence status within the IWC’s management framework. To ensure conservation of the whale populations, a forthright exposition of the origins, development and character of these hunts is needed in addition to stock assessment, a risk‐averse catch limit algorithm and appropriate mechanisms within the whaling communities to ensure compliance. The hunts for Bowhead Whales (Balaena mysticetus) and Gray Whales (Eschrichtius robustus) in the Arctic and North Pacific, respectively, and Sperm Whales (Physeter macrocephalus) in Indonesia have long histories and local origins. Those for Humpback Whales (Megaptera novaeangliae) in the Lesser Antilles and at Tonga in the South Pacific were introduced by foreign commercial whalers. Whale hunting in the Philippines appears to have originated both locally and as a result of foreign influence. The relatively recent initiation of whaling for Fin Whales (Balaenoptera physalus) and Minke Whales (Balaenoptera acutorostrata) in Greenland required introduced technology but can be viewed as a modern adaptation of an ancient tradition. Consensus in deciding how to classify and manage non‐industrial whaling has been, and will remain, elusive. Even with common definitions of key terms such as ‘subsistence’, ‘commercial’ and ‘aboriginal’, interpretations will depend on whether one’s priorities are whale‐centred or human‐centred.
Dissemination barriers to Ross River virus in Aedes vigilax and the effects of larval nutrition on their expression
Authors: Jennings C. D. , Kay B. H. 
Published: March 2003

SummaryEffects of larval nutrition on vector competence of the mosquito Aedes vigilax (Skuse) (Diptera: Culicidae) from Townsville, north Queensland, for Ross River virus (RR) were examined. Larvae were reared on three different diets to create three significantly different size classes of adult mosquito. These were fed on serial dilutions of RR and then sampled on alternate days so the progression of the virus through the mosquito could be examined. No differences of vector competence could be attributed to larval nutrition. Barriers to infection and the correlation between infection rate, viral titre and transmission of RR by Ae. vigilax were also examined. The mesenteronal barrier was the only infection barrier expressed. No correlation between viral titre and transmission was detected, but a strong correlation was found between salivary gland infection and transmission rate. From this it was possible to estimate that 98.7 ± 1.3% of Ae. vigilax with infected salivary glands transmit RR.
Biochemical characterization of insecticide resistance in the German cockroach, Blattella germanica, from Malaysia
Authors: Lee C. Y. , Hemingway J. , Yap H. H. , Chong N. L. 
Published: March 2003

SummaryThe possible insecticide resistance mechanisms of four Malaysian field‐collected strains of the German cockroach,Blattella germanica(Linnaeus) (Dictyoptera: Blattellidae), were characterized with biochemical assays and native polyacrylamide gel electrophoresis (PAGE). Elevated esterase activity (at low to moderate frequency) and altered acetylcholinesterase (low frequency) were detected in all field strains, while elevated glutathione S‐transferase levels were present in only two strains. Seven esterase bands were separated by native PAGE; a greater intensity occurred in three bands in the resistant strains compared to the susceptible strain. Inhibition studies using specific inhibitors on polyacrylamide gels suggested that the slowest of these three esterases is a cholinesterase, while the other two are carboxylesterases with a preference for β‐ over α‐naphthyl acetate.
Human sweat and 2‐oxopentanoic acid elicit a landing response from Anopheles gambiae
Authors: Healy T. P. , Copland M. J. W. 
Published: March 2003

SummaryA wind tunnel bioassay and video to observe mosquitoes landing on heated glass cylinders were used to test sweat and some derivatives for responses of Anopheles gambiae Giles (Diptera: Culicidae), a highly anthropophilic African species of malaria vector. Filter papers impregnated with human sweat and a diethyl ether extract from the filter papers elicited significantly more landings than a water control (P < 0.001). The concentration of lactic acid in the extract was determined by GLC assay, but bioassays of an equivalent dose of lactic acid (from a commercial supplier) did not elicit landings. Chemical analysis of the extract by combined GLC/mass spectrometry indicated the presence of 73 compounds, of which 40 were tentatively identified. The major components of the extract were aliphatic carboxylic acids. An artificial blend of 22 carboxylic acids did not elicit landings. Bioassays of 2‐oxopentanoic acid elicited significantly more landings (P < 0.001). The possible importance of oxo‐carboxylic acids for host‐seeking by anthropophilic mosquitoes is discussed and their use for trapping is suggested.
Control of flea populations in a simulated home environment model using lufenuron, imidacloprid or fipronil
Authors: Jacobs D. E. , Hutchinson M. J. , Ryan W. G. 
Published: March 2003

SummaryControl strategies were evaluated over a 6‐month period in a home simulation model comprising a series of similar carpeted pens, housing matched groups of six cats, in which the life‐cycle of the fleaCtenocephalides felis felisBouché (Siphonaptera: Pulicidae) had been established. Additional adult fleas were placed on the cats at intervals to mimic acquisition of extraneous fleas from outside the home. Treatment strategies included a single subcutaneous deposition of injectable lufenuron supported by initial treatments with a short‐acting insecticidal spray, or monthly topical applications of imidacloprid or fipronil. An untreated control group indicated that conditions were suitable for flea replication and development. Controls had to be combed on 18 occasions to remove excessive flea burdens and two developed allergic reactions. Lufenuron cats were combed once and required two insecticidal treatments in the first month to achieve control. Even so, small flea burdens were constantly present thereafter. Imidacloprid and fipronil treatments appeared to give virtually complete control throughout. Single fleas were found on imidacloprid cats on two occasions, whereas none were recovered from fipronil cats at any time after the first treatment. Tracer cats were used to monitor re‐infestation rates at the end of the trial period. Small numbers of host‐seeking fleas were demonstrated in all treatment pens, indicating that total eradication had not been accomplished. It is concluded that the home environment simulation model incorporating tracer animals could provide a powerful tool for studying flea population dynamics under controlled conditions but improved techniques are needed for quantifying other off‐host life‐cycle stages.
Development and integration of CAL: a case study in medicine
Authors: Hamilton  , Furnace  , Duguid  , Helms  , Simpson  
Published: March 2003

ContextThe Faculty of Medicine and Medical Sciences at the University of Aberdeen viewed the use of Computer Assisted Leaning (CAL) and other IT based learning resources as a possible way of coping with an increase in student numbers whilst maintaining or increasing the quality of medical teaching.ObjectivesOur primary objective was to develop and integrate Computer Assisted Learning (CAL) applications into the undergraduate medical curriculum.Subjects/MaterialsA wide spectrum of CAL applications were developed dealing with many topics in the curriculum.MethodsWe formulated a structured approach to CAL development by establishing a team of professionals (forming a CAL Unit), using existing expertise and by implementing a process to ensure that the CAL had a maximum impact upon the curriculum. The CAL included multimedia tutorials, learning guides, computer aided assessment (CAA) and Model Patients.ResultsThere are now over 150 IT based learning resources in our curriculum and course evaluation has showed that these have been well received by students.ConclusionsWe conclude that with the wise use of the many skills and facilities usually available within an institution and by promoting collaborative projects with others, the production of high quality CAL is possible within most institutions.
A Delphi technique to identify and evaluate criteria for construction of PBL problems
Authors: Marchais Jacques E Des 
Published: March 2003

IntroductionIn the process of PBL implementation, faculty members often ask what are the criteria for constructing problems and subsequently evaluating them. Although experts agree on a fundamental theoretical basis for developing problems, mostly prototypical, it is difficult to find specific criteria that could be used in constructing PBL problems.MethodA Delphi technique using six independent judges from the Rouen School of Medicine, France, answered this question. It took four rounds and five months.ResultsNine criteria were identified and rank‐ordered according to their relative importance: 1 – stimulating thinking, analysis, and reasoning (openness 6·8 points); 2 – assuring self‐directed learning (autonomy 6·5); 3 – using previous basic knowledge (richness 6·2); 4 – proposing a realistic context (attractiveness 5·7); 5 – leading to the discovery of learning objectives (coverage 5·0); 6 –arousing curiosity (inquisitiveness 5·0); 7 – choosing topics related to public health (relevance 5·0); 8 – assuring contextual breadth (comprehensiveness 4·8); and 9 – choosing an appropriate vocabulary (medical encoding 4·7).DiscussionThe identification represents a fresh outlook on the PBL process, from judges who had recent experience in constructing PBL problems. Related to Barrow’s dimensions, these criteria could be seen as a more concrete and specific level of conceptualization. Paired with those found in the literature, they match six out nine already identified, although not prioritized criteria.ConclusionJudges from a school just having implemented PBL, found that Reasoning and Autonomy are the most important criteria for constructing PBL problems.
A population genetic comparison of large‐ and small‐bodied sage grouse in Colorado using microsatellite and mitochondrial DNA markers
Authors: Oyler‐mccance S. J. , Kahn N. W. , Burnham K. P. , Braun C. E. , Quinn T. W. 
Published: March 2003

AbstractSage grouse (Centrocercus urophasianus) from southwestern Colorado and southeastern Utah (United States) are 33% smaller than all other sage grouse and have obvious plumage and behavioural differences. Because of these differences, they have been tentatively recog—nized as a separate ‘small‐bodied’ species. We collected genetic evidence to further test this proposal, using mitochondrial sequence data and microsatellite markers to determine whether there was gene flow between the two proposed species. Significant differences in the distribution of alleles between the large‐ and small‐bodied birds were found in both data sets. Analysis of molecular variance (amova) revealed that 65% of the variation in mitochondrial DNA (mtDNA) haplotypes could be explained by the large‐ vs. small‐bodied distinction. Genetic distances and neighbour‐joining trees based on allelic frequency data showed a distinct separation between the proposed species, although cladistic analysis of the phylogenetic history of the mitochondrial sequence haplotypes has shown a lack of reciprocal monophyly. These results further support the recognition of the small‐bodied sage grouse as a distinct species based on the biological species concept, providing additional genetic evidence to augment the morphological and behavioural data. Furthermore, small‐bodied sage grouse had much less genetic variation than large‐bodied sage grouse, which may have implications for conservation issues.
Distribution of Gymnostoma spp. microsymbiotic Frankia strains in New Caledonia is related to soil type and to host‐plant species
Authors: Navarro E. , Jaffre T. , Gauthier D. , Gourbiere F. , Rinaudo G. , Simonet P. , Normand P. 
Published: March 2003

AbstractThe diversity of the Frankia strains that are naturally in symbiosis with plants belonging to the Gymnostoma genus in New Caledonia was investigated. A direct molecular characterization of DNA extracted from nodules was performed, followed by characterization by restriction fragment length polymorphism (RFLP) of the ribosomal rrs–rrl (16S–23S) intergenic spacer (IGS) polymerase chain reaction (PCR)‐amplified region. Seventeen different patterns were identified among the 358 microsymbiotic strains studied in the eight species of host plant present in New Caledonia. This genotypical approach permitted us to show that a large diversity existed among the patterns and that these did not exhibit a strict specificity to any host‐plant species comparable with that previously found in the Casuarina and Allocasuarina symbioses in Australia. Despite this lack of specificity, a correspondence analysis nevertheless showed that the distribution of these patterns was related to soil type and to host‐plant species. Furthermore, several Frankia strains were exclusively associated with the ultramafic soils.
Interaction between the endophytic fungus Epichloë bromicola and the grass Bromus erectus: effects of endophyte infection, fungal concentration and environment on grass growth and flowering
Authors: Groppe K. , Steinger T. , Sanders I. , Schmid B. , Wiemken A. , Boller T. 
Published: March 2003

Abstract Epichloë bromicola is an endophytic fungal species that systemically and perennially colonizes intercellular spaces of leaf blades, leaf sheaths and culms of Bromus grass species. E. bromicola causes choke disease in B. erectus, suppressing maturation of most, if not all, host inflorescences. In an investigation of the interaction between fungus and host, we used a quantitative polymerase chain reaction technique to estimate the amount of fungal DNA, and thereby fungal concentration, in host plants. Fungal concentration was directly correlated with vegetative vigour of the plant, as measured by longest leaf length, number of tillers and vegetative above‐ground biomass, suggesting that, during vegetative growth, the endophytic fungus is most beneficial for the plant when present in high concentrations. In contrast, the reproduction of the plant, as measured by the number of functional inflorescences, was inversely correlated with fungal concentration: the majority of infected plants, and all that were associated with high concentrations of fungi, were diseased. Thus, the benefit of endophyte infection for the plant is coupled with the disadvantages of infertility. Fungal concentration was shown to be at least in part genetically determined because fungal concentration differed significantly in different plant–endophyte genotype combinations (symbiotum). In a field experiment with normal and CO2‐enriched environments, elevated CO2 levels favoured fungal reproductive vigour over host reproductive vigour, suggesting that these plant endophytes would be at a selective advantage in a corresponding environmental‐change scenario. We conclude that a dynamic and complex relationship between fungal endophyte infection, fungal concentration, genotype and environment affects growth and fecundity of B. erectus and should contribute to the evolution of these plant–fungal interactions.