Chromosomal Aberrations in Canine Gliomas Define Candidate Genes and Common Pathways in Dogs and Humans.

Spontaneous gliomas in dogs occur at a frequency similar to that in humans and may provide a translational model for therapeutic development and comparative biological investigations. Copy number alterations in 38 canine gliomas, including diffuse astrocytomas, glioblastomas, oligodendrogliomas, and mixed oligoastrocytomas, were defined using an Illumina 170K single nucleotide polymorphism array. Highly recurrent alterations were seen in up to 85% of some tumor types, most notably involving chromosomes 13, 22, and 38, and gliomas clustered into 2 major groups consisting of high-grade IV astrocytomas, or oligodendrogliomas and other tumors.

Qualitative and Quantitative Characteristics of the Electroencephalogram in Normal Horses during Administration of Inhaled Anesthesia.

Background: The effects of anesthesia on the equine electroencephalogram (EEG) after administration of various drugs for sedation, induction, and maintenance are known, but not that the effect of inhaled anesthetics alone for EEG recording.

Objective: To determine the effects of isoflurane and halothane, administered as single agents at multiple levels, on the EEG and quantitative EEG (qEEG) of normal horses.

Animals: Six healthy horses.

Electroencephalogram of Healthy Horses During Inhaled Anesthesia.

Background: Previous study of the diagnostic validity of electroencephalography (EEG) to detect abnormalities in equine cerebral cortical function relied on the administration of various drugs for sedation, induction, and maintenance of general anesthesia but used identical criteria to interpret recordings.

Objectives: To determine the effects of 2 inhalation anesthetics on the EEG of healthy horses.

Animals: Six healthy horses.

Molecular signalling pathways in canine gliomas.

In this study, we determined the expression of key signalling pathway proteins TP53, MDM2, P21, AKT, PTEN, RB1, P16, MTOR and MAPK in canine gliomas using western blotting. Protein expression was defined in three canine astrocytic glioma cell lines treated with CCNU, temozolamide or CPT-11 and was further evaluated in 22 spontaneous gliomas including high and low grade astrocytomas, high grade oligodendrogliomas and mixed oligoastrocytomas. Response to chemotherapeutic agents and cell survival were similar to that reported in human glioma cell lines.

Electrophysiologic confirmation of heterogenous motor polyneuropathy in young cats.

Background: Reports of motor polyneuropathies in young cats are scarce. Further, in-depth electrophysiologic evaluation to confirm a motor polyneuropathy in young cats of various breeds other than 2 Bengal cats is lacking.

Hypothesis/objectives: To confirm a motor polyneuropathy in young cats of various breeds.

Sensory nerve conduction and somatosensory evoked potentials of the trigeminal nerve in horses with idiopathic headshaking.

Background: Idiopathic headshaking (HSK) in horses is a distressing disorder in which the etiology and pathophysiology are unknown.

Hypothesis: Differences in sensory function of the trigeminal nerve exist between healthy and affected horses.

Animals: Six healthy mature geldings and 6 mature geldings with idiopathic HSK.

Magnetic resonance imaging features of intracranial granular cell tumors in six dogs.

Magnetic resonance (MR) imaging characteristics of intracranial granular cell tumors (GCTs) have been previously reported in three dogs. The goal of this retrospective study was to examine a larger number of dogs and determine whether distinctive MR characteristics of intracranial GCTs could be identified. Six dogs with histologically confirmed intracranial GCTs and MR imaging were included.

Qualitative and quantitative characteristics of the electroencephalogram in normal horses after sedation.

Background: The administration of certain sedatives has been shown to promote sleep in humans. Related agents induce sleep-like behavior when administered to horses. Interpretation of electroencephalograms (EEGs) obtained from sedated horses should take into account background activity, presence of sleep-related EEG events, and the animal's behavior.

TP53 mutations in canine brain tumors.

The p53 tumor suppressor gene (TP53) is the most frequently altered gene in human cancer. Mutation of the gene has been shown to be an important mechanism of p53 pathway inactivation in a variety of human brain tumors, particularly those of astrocytic origin. Genomic DNA from a series of 37 glial and 51 nonglial canine brain tumors was sequenced to determine the frequency of TP53 gene mutations involving exons 3-9.

Evaluation of epidemiological, clinical, and pathological features of neuroaxonal dystrophy in Quarter Horses.

Objective: To describe epidemiological, clinical, and pathological features of neuroaxonal dystrophy in Quarter Horses (QHs) on a single farm.

Design: Prospective case series. Animals-148 horses.

Repetitive stimulation of the common peroneal nerve as a diagnostic aid for botulism in foals.

Background: Botulism is a potentially fatal paralytic disorder for which definitive diagnosis is difficult.

Objectives: To determine if repetitive stimulation of the common peroneal nerve will aid in the diagnosis of botulism in foals.

Animals: Four control and 3 affected foals.

Effects of isoflurane anesthesia on cerebrovascular autoregulation in horses.

Objective: To test a hypothesis predicting that isoflurane would interfere with cerebrovascular autoregulation in horses and to evaluate whether increased mean arterial blood pressure (MAP) would increase cerebral blood flow and intracranial pressure (ICP) during isoflurane anesthesia.

Animals: 6 healthy adult horses.

Procedures: Horses were anesthetized with isoflurane at a constant end-tidal concentration sufficient to maintain MAP at 60 mm Hg.

Canine spontaneous glioma: a translational model system for convection-enhanced delivery.

Canine spontaneous intracranial tumors bear striking similarities to their human tumor counterparts and have the potential to provide a large animal model system for more realistic validation of novel therapies typically developed in small rodent models. We used spontaneously occurring canine gliomas to investigate the use of convection-enhanced delivery (CED) of liposomal nanoparticles, containing topoisomerase inhibitor CPT-11. To facilitate visualization of intratumoral infusions by real-time magnetic resonance imaging (MRI), we included identically formulated liposomes loaded with Gadoteridol.

Spontaneous canine gliomas: overexpression of EGFR, PDGFRalpha and IGFBP2 demonstrated by tissue microarray immunophenotyping.

Fifty-seven spontaneous canine gliomas were histologically classified and graded using the latest World Health Organization (WHO 2007) criteria for classification of human gliomas. A total of 19 canine astrocytomas were classified as follows: grade IV (GBM) n = 7; grade III n = 5; and grade II, n = 7. Thirty-eight oligodendrogliomas were classified as either grade III (anaplastic) n = 35 or low grade II n = 3.

Evaluation of deafness in American Paint Horses by phenotype, brainstem auditory-evoked responses, and endothelin receptor B genotype.

Objective: To evaluate deafness in American Paint Horses by phenotype, clinical findings, brainstem auditory-evoked responses (BAERs), and endothelin B receptor (EDNBR) genotype.

Design: Case series and case-control studies.

Animals: 14 deaf American Paint Horses, 20 suspected-deaf American Paint Horses, and 13 nondeaf American Paint Horses and Pintos.

Vacuolar myopathy in a dog resembling human sporadic inclusion body myositis.

Sporadic inclusion body myositis (sIBM) is the most common myopathy in people over the age of 50 years. While immune-mediated inflammatory myopathies are well documented in dogs, sIBM has not been described. An 11-year-old dog with chronic and progressive neuromuscular dysfunction was evaluated for evidence of sIBM using current pathologic, immunohistochemical and electron microscopic diagnostic criteria.

Anatomic compression caused by high-volume convection-enhanced delivery to the brain.

Objective: Our group has pioneered the use of gadoteridol-loaded liposomes (GDLs) in convection-enhanced delivery (CED) using real-time magnetic resonance imaging (MRI) to visualize the distribution of therapeutic agents in nonhuman primate and canine brains. We have shown that this procedure is highly predictable and safe. In the course of recent studies, however, we noted that infusion of large volumes caused local anatomic alterations, such as ventricular compression, to occur.

Quantitative assessment of blood volume and permeability in cerebral mass lesions using dynamic contrast-enhanced computed tomography in the dog.

Rationale And Objectives: To evaluate cerebral blood volume (CBV) and permeability (PS) in spontaneously occurring cerebral neoplastic and non-neoplastic lesions in dogs using dynamic contrast-enhanced computed tomography (DCE-CT).

Materials And Methods: Dogs presenting with spontaneous intracranial lesions (n = 16) underwent DCE-CT at the level of the lesion followed by a histologically confirmed diagnosis from a CT-guided stereotactic biopsy. Data post-processing was performed with commercially available CT software (GEMS Advantage Workstation 4.

Expression of the tumor suppressor genes NF2, 4.1B, and TSLC1 in canine meningiomas.

Meningiomas are common primary brain tumors in dogs; however, little is known about the molecular genetic mechanisms involved in their tumorigenesis. Several tumor suppressor genes have been implicated in meningioma pathogenesis in humans, including the neurofibromatosis 2 (NF2), protein 4.1B (4.

Muscular dystrophy associated with alpha-dystroglycan deficiency in Sphynx and Devon Rex cats.

Recent studies have identified a number of forms of muscular dystrophy, termed dystroglycanopathies, which are associated with loss of natively glycosylated alpha-dystroglycan. Here we identify a new animal model for this class of disorders in Sphynx and Devon Rex cats. Affected cats displayed a slowly progressive myopathy with clinical and histologic hallmarks of muscular dystrophy including skeletal muscle weakness with no involvement of peripheral nerves or CNS.