Bovine herpesvirus glycoprotein D: a review of its structural characteristics and applications in vaccinology

The viral envelope glycoprotein D from bovine herpesviruses 1 and 5 (BoHV-1 and -5), two important pathogens of cattle, is a major component of the virion and plays a critical role in the pathogenesis of herpesviruses. Glycoprotein D is essential for virus penetration into permissive cells and thus is a major target for virus neutralizing antibodies during infection. In view of its role in the induction of protective immunity, gD has been tested in new vaccine development strategies against both viruses. Subunit, DNA and vectored vaccine candidates have been developed using this glycoprotein as the primary antigen, demonstrating that gD has the capacity to induce robust virus neutralizing antibodies and strong cell-mediated immune responses, as well as protection from clinical symptoms, in target species. This review highlights the structural and functional characteristics of BoHV-1, BoHV-5 and where appropriate, Human herpesvirus gD, as well as its role in viral entry and interactions with host cell receptors. Furthermore, the interactions of gD with the host immune system are discussed. Finally, the application of this glycoprotein in new vaccine design is reviewed, taking its structural and functional characteristics into consideration.     

A clinical evaluation of a headless, titanium, variable-pitched, tapered, compression screw for repair of nondisplaced lateral condylar fractures in thoroughbred racehorses

OBJECTIVE: To report clinical evaluation of headless compression screws for repair of metacarpal/metatarsal (MC/MT3) condylar fractures in horses. STUDY DESIGN: Retrospective case study. SAMPLE POPULATION: Racing Thoroughbreds (n=16) with nondisplaced lateral condylar fractures of MC/MT 3. METHODS: Medical records (1999-2004) of horses with nondisplaced longitudinal fractures of the lateral condyle of MC/MT3 were reviewed. Pre-operative variables retrieved were: patient age, gender, limb involvement, injury occurrence, fracture length, and width, evidence of palmar comminution and degenerative joint disease, number of pre-injury starts, and pre-injury earnings. Post-operative variables retrieved were: surgical complications, surgical time, number of race starts, and post-operative earnings. RESULTS: MC3 (n=11) and MT3 (5) nondisplaced longitudinal fractures of the lateral condyle were repaired with Acutrak Equine (AE) screws. Left front limb fractures were most common (8) followed by left hind (5) and right front (3). Nine fractures occurred during training and 7 during racing; 4 fractures had palmar comminution. No surgical complications occurred. Of 15 horses that returned to training, 11 (73%) raced 306+/-67 days after injury and had greater mean (+/-SD) post-injury earnings/start ($5290.00+/-$8124.00) than pre-injury ($4971.00+/-$2842.00). Screw removal was not required in any horse. CONCLUSION: The AE screw is a viable option for repair of nondisplaced lateral condylar MC/MT3 fractures in Thoroughbred racehorses. CLINICAL RELEVANCE: Adequate stability of nondisplaced lateral condylar fractures can be achieved with a headless tapered compression screw while avoiding impingement on the collateral ligaments and joint capsule of the fetlock joint.     

Preliminary analysis of toxicity of benzoxazinones and their metabolites for folsomia Candida

The overall objective of this study was to explore the toxicity of benzoxazinone allelochemicals and their metabolites to Folsomia candida (Collembola: Isotomidae) (Willem, 1902). Experimental tests showed transformation products to have more pronounced toxicity than parent compounds. The underlying relationship between the chemical structure and toxicity was then studied using three-dimensional QSAR approaches, and results highlighted the role of the steric contribution.     

Comparison of the use of new handheld tonometers and established applanation tonometers in dogs

OBJECTIVE: To examine the practical aspects, accuracy, and reproducibility of 2 new automatic handheld tonometers in dogs and compare them with results for 2 established applanation tonometers. ANIMALS: 15 freshly enucleated canine eyes for manometric evaluation and 20 conscious research dogs, 20 client-owned dogs, and 12 dogs with acute glaucoma for clinical tonometry. PROCEDURE: Calibration curves were determined for all 4 tonometers on 15 enucleated canine eyes. Intraocular pressure (IOP) was measured with each tonometer consecutively in conscious dogs, with the MacKay-Marg applanation tonometer as the reference device. Measurements were repeated in 20 sedated dogs. An induction-impact tonometer was evaluated clinically on dogs with acute glaucoma. Additionally, measurements obtained by an experienced and an inexperienced examiner and with or without use of topical anesthesia were compared. RESULTS: The portable pneumatonometer was cumbersome and time-consuming. Compared with results for the reference applanation tonometer, and confirmed by manometry, the portable pneumatonometer increasingly underestimated actual IOP values with increasing IOP. The induction-impact tonometer provided accurate and reproducible measurement values. There was a significant strong correlation between the IOP values obtained by the 2 examiners (r2, 0.82) and also with or without topical anesthesia (r2, 0.86). In dogs with glaucoma, the fitted line comparing values for the reference applanation tonometer and induction-impact tonometer closely resembled an ideal 1:1 relationship. CONCLUSIONS AND CLINICAL RELEVANCE: Use of the portable pneumatonometer in dogs appears to have disadvantages. The induction-impact tonometer appears to provide a promising alternative to the use of applanation tonometers in dogs.     

Microbiological baseline study of poultry slaughtered in provincially inspected abattoirs in Alberta, Canada

Studies to determine baseline levels of microbial contaminants and foodborne bacterial pathogens are needed to evaluate the effectiveness of Hazard Analysis Critical Control Point (HACCP) programs, Good Manufacturing/Production Practices, and various interventions. In 2004 and 2005 poultry carcass rinses from provincially inspected abattoirs in Alberta, Canada, were tested to determine the levels of aerobic plate count bacteria, coliform bacteria, and generic Escherichia coli, the prevalence and levels of Campylobacter spp., and the prevalence of Salmonella spp. and Shiga toxin-producing E. coli (STEC). Samples were collected from 3 high volume and 62 low volume abbatoirs. All samples (1296) were positive for aerobic plate count bacteria, with 98.8% of samples having counts of 100 000 or less colony forming units (CFU)/cm². Coliform bacteria were isolated from 99.7% of the 1296 carcasses and were recovered at levels of ≤ 1000 CFU/cm² for 98.3% of the samples. Generic E. coli were recovered from 99.1% of the 1296 carcasses at levels of ≤ 1000 CFU/cm² for 98.6% of the samples. Seventy five percent of 1234 samples that were tested for Campylobacter were positive; 37.5% of 1295 samples that were tested for Salmonella were positive; and only 2 of 1296 samples tested for STEC were positive (0.15%).     

A comprehensive study of dog bites in Spain, 1995-2004

Dog bites in humans are a complex problem embracing public health and animal welfare. To prevent dog bites it is necessary to have comprehensive epidemiological data that allow the identification of associated risk patterns. This study was aimed at investigating the problem posed by dog bites in Spain. The epidemiology of medically attended dog bite-related incidents reported in Aragón was analysed from 1995 to 2004. Bite incidents were mostly associated with: (1) low-population areas (71.3/100,000 inhabitants); (2) males and children, particularly those aged 5–9; (3) single injuries directed to the head and neck area in children and to the extremities in adults; (4) young, male, medium to large, owned dogs that were known to the victim; (5) summer months, and (6) specific circumstances such as human interference with knocked down and fighting dogs. In the light of these risk patterns, a wide range of specific preventive measures could be proposed.     

Contrasting mitochondrial DNA diversity estimates in Austrian Scutovertex minutus and S. sculptus (Acari, Oribatida, Brachypylina, Scutoverticidae)

Important insights into the evolutionary and demographic history of species can be obtained from inter-specific comparisons of patterns and from determing the degree of genetic diversity. Analysis of sequences of the mitochondrial cytochrome oxidase I (COI) gene revealed remarkable differences in mtDNA diversity estimates and the distribution of mitochondrial lineages between the two closely related oribatid mite species Scutovertex sculptus and S. minutus in Austria. Divergence time estimates revealed an age of approximately 48-74 Myr for the split between the two Scutovertex species and age estimates of about 2-3 and 8-12 Myr for the most recent common ancestors of Austrian S. minutus and S. sculptus, respectively. Genetic diversity was considerably lower in S. minutus than in S. sculptus. A clear geographic sub-division into samples originating from north and south of the Central Alps became evident in S. minutus, whereas no phylogeographic structure was found in S. sculptus. Together with a high genetic diversity this is suggestive of a panmictic population and exceptional dispersal ability, most probably facilitated by phoresy on birds. The lack of sub-structure with regard to habitat types in S. sculptus suggests that this species can cope with a wide range of environmental conditions.     

Limitations to using benomyl in evaluating mycorrhizal functioning

Arbuscular mycorrhizal (AM) grasses compete for nutrients with ectomycorrhizal (EM) pine in the southeastern United States. Our objective was to determine if benomyl could be used to selectively inhibit the function of AM and thereby reduce grass competition in the field. The effects of Benlate (active ingredient: benomyl) in the greenhouse and field were evaluated. No effect was observed on pine inoculated with Pisolithus tinctorius in the greenhouse. Colonized root length of benomyl-treated Zea mays L. plants inoculated with Glomus sp. in the greenhouse remained static over time and the response was not dose dependent at concentrations of 0, 20, 60 and 150kg benomyl ha^–1 equivalent. In contrast, colonization of nontreated plants increased over time. In the field, a minimal reduction of grass colonization was observed following four applications of benomyl ranging from 5 to 20kgha^–1. We conclude that benomyl can successfully inhibit development of AM fungi under controlled conditions in the greenhouse with no inhibitory effects on the EM fungus P. tinctorius; however, in the field several factors may interfere with the effect of benomyl on AM fungi. These factors include: (a) the presence of ground cover which obstructs penetration of the fungicide to the soil, (b) timing of application in relation to mycorrhizal development, and (c) the application method of benomyl, a soil drench being preferable to a foliar spray. Received: 30 September 1996     

Relationships between salicylic acid content,phenylalanine ammonia-lyase (PAL) activity,and resistance of barley to aphid infestation

It has been suggested that salicylic acid (SA) is a signal in acquired resistance to pathogens in several plants. Also, it has been suggested that infestation of plants causes an increase in the activity of phenylalanine ammonia-lyase (PAL), a key phenolic biosynthesis enzyme. The purpose of this work was to investigate whether the induction of SA and PAL activity is related to the susceptibility of barley to aphid infestation. The induction of free and conjugated SA in two barley cultivars that differ in susceptibility to aphids was analyzed. Analyses of several physiological parameters showed that cv. UNA-80 was more susceptible to the aphid Schizaphis graminum than cv. LM-109. Salicylic acid was not detected in noninfested plants. Levels of free and conjugated SA in cv. LM-109 and of conjugated SA in cv. UNA-80 increased with aphid infestation, whereas the levels of free SA in cv. UNA-80 remained high under all infestation degrees. Maximum values reached in both cultivars were not significantly different. With respect to PAL activity, cv. LM-109 showed a significantly higher specific activity than cv. UNA-80, the more susceptible cultivar. The relationship between the susceptibility of a plant to aphid and SA induction and PAL activity is discussed.     

Chemical basis for the antifeedant activity of natural hydroxamic acids and related compounds

Natural hydroxamic acids and related compounds derived from the 1,4-benzoxazin-3-one structure show antifeedant activity against the aphid Rhopalosiphum padi. This antifeeding activity is based on the electrophilic character of the hydroxamic acid function, the opening of the hemiacetal function and the lipophilic character of the molecule. In addition, the antifeedant activity of the aqueous extracts of different tissues of Acanthus mollis (Acanthaceae) was determined. The activity observed is attributed to the presence of 2,4-dihydroxy-1,4-benzoxazin-3-one in the extracts.