DIPHOSPHONATE TREATMENT OF A PRIMARY OSTEOSARCOMA IN A DOG: A CASE REPORT

The following sequence of treatments was administered to a Saint Bernard dog with a primary distal right radius osteosarcoma: 54 days of daily disodium 1-hydroxyethylidenediphosphonate (HEDP) subcutaneous injections; 53 days of HEDP per os ; one ³²P-HEDP intravenous injection. During the pretreatment period, there was an extensive increase in calcific tumor growth and osteoblastic proliferation. After the subcutaneous HEDP treatment, almost complete tumor necrosis was seen. After the oral HEDP treatment, only the deepest tumor portion contained active osteoblasts, calcific growth of the tumor was completely blocked, and uptake of ^99mTc-Sn-HEDP was reduced to one fourth of the pretreatment uptake. After a single ³²P-HEDP dose, large areas of tumor necrosis were evident histopathologically. However, subsequent resumption of cellular activity occurred in the tumor, and the uptake of ^99mTc-Sn-HEDP increased to pretreatment values. These data suggest that systemically administered HEDP should be studied further for its possible therapeutic potential in the treatment of osteosarcoma and indicate a need for further study of ³²P-HEDP or possibly ³³P-HEDP.     

Biochemical evaluation of mitochondrial respiratory chain enzymes in canine skeletal muscle

OBJECTIVE: To perform respiratory chain enzymatic activity assays on canine skeletal muscle biopsy specimens and establish reference range values of skeletal muscle enzyme activities for dogs. SAMPLE POPULATION: Biopsy specimens from the vastus lateralis muscle were obtained from 24 dogs (8 sexually intact males and 14 sexually intact females) ranging from 15 months to 6 years of age. PROCEDURE: Mean values of citrate synthase, cytochrome-c oxidase, succinate dehydrogenase, succinate dehydrogenase-cytochrome-c reductase, nicotinamide adenine dinucleotide (NADH) dehydrogenase, and NADH dehydrogenase-cytochrome-c reductase activities were established by use of 6 standard spectrophotometric assays for respiratory chain enzyme analysis. RESULTS: Compared with published data for skeletal muscle enzyme activities in humans, skeletal muscle enzyme activities in dogs were 2- to 4-fold higher. Additionally, citrate synthase activity, a marker for mitochondrial volume, was positively correlated with age in dogs, suggesting that mitochondrial volume increases with age, although no apparent change in respiratory chain enzymatic activity with an increase in age was found. CONCLUSIONS AND CLINICAL RELEVANCE: Reference range values for skeletal muscle enzyme activities of dogs are needed to accurately interpret results of respiratory chain enzymatic activity assays. During investigation of metabolic myopathies, if skeletal muscle biopsy specimens are evaluated for respiratory chain enzyme kinetics, they should be performed and evaluated in concert with skeletal muscle biopsy specimens from clinically normal animals of the same species.     

Treatment of tracheal collapse with an intraluminal stent in a miniature horse

A 7-month-old miniature horse was referred for respiratory distress. Tracheal collapse at the level of the thoracic inlet was diagnosed. An intraluminal nitinol stent was placed with endoscopic guidance. Respiratory function was restored immediately after stent placement. The main complication observed during a 14-month follow-up period was growth of granulation tissue through the stent, which was controlled satisfactorily by electrocautery performed during endoscopy with the horse standing. Treatment of tracheal collapse with an intraluminal stent is an effective, practical, and minimally invasive procedure in miniature and young equids and ponies.     

Use of structured antedependence models for the genetic analysis of growth curves

Growth curve analysis is an important issue for many agricultural and laboratory species, for both phenotypic and genetic studies. The aim of this paper is to present the use of a novel statistical approach, namely the structured antedependence (SAD) models, to deal with this issue. The basic idea of these models is that an observation at time t can be explained by the previous observations. These models are especially appropriate to deal with cumulative traits such as growth, as BW at age t clearly depends on BW measures at ages (t -1), (t -2), etc. These models were applied on an INRA experimental Charolais herd data set. The data comprised BW records for 560 cows born over an 11-yr period (from 1988 to 1998) from 60 sires and 369 dams. The proposed SAD models were compared with the well-known random regression (RR) models that are already widely used in various areas of longitudinal data analysis. It was found that the SAD models fit the growth process better with far fewer parameters than the RR models (9 instead of 16 covariance parameters for the phenotypic analysis, and 14 instead of 21 for the genetic analysis). Despite this smaller number of covariance parameters, the likelihood value was found to be much higher with the SAD vs. the RR models, with a difference of 262.9 for the phenotypic analysis with a quartic polynomial for the RR and 751.5 for the genetic analysis with a cubic polynomial for both the genetic and environmental parts of the RR model. The SAD models also proved to be better able to interpolate missing values. Heritability, genetic, and environmental correlation coefficients were estimated for weights from birth to adulthood. The structured antedependence models proved, in this study, to be very appropriate to model growth data in a parsimonious and flexible way.     

The epidemiology and diagnosis of bluetongue with particular reference to Corsica

Bluetongue (BT) and/or BT viruses (BTV) have been identified in the Mediterranean basin and the Balkans each year from 1998 to 2002 and in particular BTV serotype 2 in the French Island of Corsica (2000 and 2001). In response to these virus incursions, the French Veterinary Authorities carried out epidemiological studies that included virological, serological and entomological analysis, and two vaccination campaigns performed in the winter of 2000/2001 and the winter and spring of 2001 and 2002. Rapid and reliable serotype differentiation is essential at the start of an outbreak to allow an early selection of vaccine to control the spread of the virus. Thus, molecular tools, that complement conventional methods, have been developed for early detection of infection, determination of the serotype, and differentiation between natural infection and vaccination. Serological results showed that the first vaccination campaign during the winter of 2000/2001 did not provide full protection for all sheep and during the summer of 2001, 335 sheep flocks in Corsica were again infected by BTV 2 (7-fold more that in 2000). Entomological studies have demonstrated that the only proven vector of the disease, Culicoides imicola, was present in the island in 2000 and that it has successfully established itself in Corsica. The safety and immunogenicity of the commercial South African vaccine were studied. Fourteen sheep were vaccinated and then observed for clinical signs. Blood, sera, spleen and lymph nodes were collected and analyzed, and the results confirmed the safety and potency of using this vaccine to protect sheep from clinical disease. As a result, an intensive vaccination campaign was performed during winter and spring 2001/2002. No cases of BT had been observed by the end of summer 2002, indicating that the vaccination campaign has been successful in protecting sheep from infection.     

Antioxidant capacity of black currant varies with organ, season, and cultivar

Small berries such as black currant constitute one of the important sources of potential health-promoting phytochemicals because these fruits are rich sources of compounds with high antioxidant properties. In this work, antioxidant capacities of different parts (buds, leaves, fruits) of various black currant cultivars were compared throughout the growing season with the aim to prepare extracts with high antioxidant capacity. Buds (opened, at the end of March) and leaves (in June) had a higher content in phenolics and antioxidants than fully ripened berries (in July) and the best yield (per branch) was obtained with the leaves collected in June due to their higher biomass. The differences observed among the eight cultivars tested were small. Concerning flavonols, quercetin was dominant in all organs and cultivars, myricetin varied widely among the cultivars, and kampferol was very low.     

Shedding routes of Coxiella burnetii in dairy cows: implications for detection and control

Reliable detection of Coxiella burnetii shedders is a critical point for the control of the spread of this bacterium among animals and from animals to humans. Coxiella burnetii is shed by ruminants mainly by birth products (placenta, birth fluids), but may also be shed by vaginal mucus, milk, and faeces, urine and semen. However, the informative value of these types of samples to identify shedders under field conditions is unknown. Our aim was then to describe the responses obtained using a real-time PCR technique applied to milk, vaginal mucus and faeces samples taken from 242 dairy cows in commercial dairy herds known to be naturally infected with Coxiella burnetii, and to assess their putative associations. Positive results were found in all types of tested samples even in faeces. No predominant shedding route was identified. Among the shedder cows, 65.4% were detected as shedders by only one route. By contrast, cows with positive results for all three samples were scarce (less than 7%). Testing a cow based on only one type of biological sample may lead to misclassify it with regards to its shedding of Coxiella burnetii and thereby underestimate the risk of bacterial spread within a herd.     

Genetic variant BDNF (Val66Met) polymorphism alters anxiety-related behavior

A common single-nucleotide polymorphism in the brain-derived neurotrophic factor (BDNF) gene, a methionine (Met) substitution for valine (Val) at codon 66 (Val66Met), is associated with alterations in brain anatomy and memory, but its relevance to clinical disorders is unclear. We generated a variant BDNF mouse (BDNF(Met/Met)) that reproduces the phenotypic hallmarks in humans with the variant allele. BDNF(Met) was expressed in brain at normal levels, but its secretion from neurons was defective. When placed in stressful settings, BDNF(Met/Met) mice exhibited increased anxiety-related behaviors that were not normalized by the antidepressant, fluoxetine. A variant BDNF may thus play a key role in genetic predispositions to anxiety and depressive disorders.