Commentary: the role of the toxicologic pathologist in academia.

Veterinary pathologists working as toxicologic pathologists in academic settings fill many vital roles, such as diagnosticians, educators, and/or researchers. These individuals have spent years investigating pathology problems that mainly or exclusively focus on the reactions of cells, organs, or systems to toxic materials. Thus, academic toxicologic pathologists are uniquely suited both to help trainees understand toxicity as a cause of pathology responses and also to provide expert consultation on toxicologic pathology. Most toxicologic pathologists in academia are employed at colleges of medicine or veterinary medicine, even though specific toxicologic pathology faculty appointments are uncommon in Europe and North America. Academic toxicologic pathologists typically receive lower financial compensation than do toxicologic pathologists in industry, but academic positions generally provide alternative rewards, such as higher workplace autonomy and scheduling flexibility, professional enrichment through student interactions, and enhanced opportunities for collaborative research and advanced diagnostic investigations. Regular participation by academic toxicologic pathologists in professional training opportunities (eg, as pathology and toxicology instructors in medical and veterinary medical courses, graduate programs, and residencies) offers an important means of engendering interest and inspiring veterinarians to select toxicologic pathology and toxicology as their own areas of future expertise.

Does Osgood-Schlatter disease exist in the dog?

Osgood-Schlatter disease (OSD) is a condition affecting human adolescents in which there is partial separation of bone fragments from the tibial tuberosity at the site of insertion of the patellar ligament to the tibial tuberosity. Tensile trauma seems to be the most likely aetiology. Clinical signs in people consist of swelling and pain at the proximal part of the tibial tuberosity and around the distal end of patellar ligament. Radiographs frequently show small ossicles at the patellar ligament insertion. Conservative treatment is usually curative. The term OSD has also been used for the canine patient. However, radiographs of these patients typically show an enlarged radiolucent line at the apophyseal plate of the tibial tuberosity. This finding is consistent with a mild avulsion fracture of the canine tibial tuberosity. Based on the radiographic differences between the two species, it seems more appropriate to use the term OSD only for people. The purpose of this paper is to review the literature on OSD in people and the reports of injuries to the proximal tibial tuberosity in dogs. In addition, a new classification system for tibial tuberosity avulsion injuries in the immature dog is proposed, with an algorithm for management of this injury.

Transglutaminase 1-deficient recessive lamellar ichthyosis associated with a LINE-1 insertion in Jack Russell terrier dogs.

BACKGROUND: Congenital, nonepidermolytic cornification disorders phenotypically resembling human autosomal recessive ichthyosis have been described in purebred dog breeds, including Jack Russell terrier (JRT) dogs. One cause of gene mutation important to humans and dogs is transposon insertions. OBJECTIVES: To describe an autosomal recessive, severe nonepidermolytic ichthyosis resembling lamellar ichthyosis (LI) in JRT dogs due to insertion of a long interspersed nucleotide element (LINE-1) in the transglutaminase 1 (TGM1) gene. METHODS: Dogs were evaluated clinically, and skin samples were examined by light and electron microscopy. Phenotypic information and genotyping with a canine microsatellite marker suggested TGM1 to be a candidate gene. Genomic DNA samples and cDNA generated from epidermal RNA were examined. Consequences of the mutation were evaluated by Western blotting, quantitative reverse transcription-polymerase chain reaction (RT-PCR) and enzyme activity from cultured keratinocytes. RESULTS: Affected dogs had generalized severe hyperkeratosis. Histological examination defined laminated to compact hyperkeratosis without epidermolysis; ultrastructurally, cornified envelopes were thin. Affected dogs were homozygous for a 1980-bp insertion within intron 9 of TGM1. The sequence of the insertion was that of a canine LINE-1 element. Quantitative RT-PCR indicated a significant decrease in TGM1 mRNA in affected dogs compared with wild-type. TGM1 protein was markedly decreased on immunoblotting, and membrane-associated enzyme activity was diminished in affected dogs. CONCLUSIONS: Based on morphological and molecular features, this disease is homologous with TGM1-deficient LI in humans, clinically models LI better than the genetically modified mouse and represents its first spontaneous animal model. This is the first reported form of LI due to transposon insertion.