Basic science knowledge underlies clinical science knowledge and clinical problem solving: evidence from veterinary medicine.

Medical sciences education emphasizes basic science learning as a prerequisite to clinical learning. Studies exploring relationships between achievement in the basic sciences and subsequent achievement in the clinical sciences generally suggest a significant positive relationship. Basic science knowledge and clinical experience are theorized to combine to form encapsulated knowledge- a dynamic mix of information that is useful for solving clinical problems. This study explores the relationship between basic science knowledge (BSK), clinical science knowledge (CSK), and clinical problem-solving ability, as measured within the context of four veterinary colleges using both college-specific measures and professionally validated, standardized measures of basic and clinical science knowledge and problem-solving ability. Significant correlations existed among all variables. Structural equation modeling and confirmatory factor analysis were used to produce models showing that newly acquired BSK directly and significantly predicted BSK retained over time and newly acquired CSK, as well as indirectly predicted clinical problem-solving ability (mediated by newly acquired CSK and BSK retained over time). These findings likely suggest a gradual development of schema (encapsulated knowledge) and not an isolated development of biomedical versus clinical knowledge over time. A broader implication of these results is that explicitly teaching basic science knowledge positively and durably affects subsequent clinical knowledge and problem-solving ability independent of instructional strategy or curricular approach. Furthermore, for veterinary colleges specifically, student performance as measured by both course-level and standardized tests are likely to prove useful for predicting subsequent academic achievement in classroom and clinical settings, licensing examination performance, and/or for identifying students likely in need of remediation in clinical knowledge.

Comparison of two portable lactate meters in dogs.

The objective of this study was to compare two portable lactate analyzers for testing canine patients in a clinical setting with a previously accepted methodology for measuring plasma lactate. Between Jan 1, 2005 and Jun 1, 2006, all samples were analyzed using two different portable analyzers (devices A and B), and 86 of those samples were also analyzed by a reference laboratory (REF). The concordance correlation coefficient (CCC) for device A and the REF was 0.949 (95% confidence interval [95% CI], 0.923-0.966). For device B and REF, the CCC was 0.990 (95% CI, 0.985-0.993). Only 8 of 85 samples (9.4%) exceeded a relative difference of 20% for device B (note that 1 of the 86 samples was not included because the lactate level fell below the detectable limit of device B), but 48 of 85 samples (56.5%) exceeded a relative difference of 20% for device A. Both portable lactate analyzers appeared to be effective in detecting clinically significant elevations in plasma lactate compared with the REF but device B had better agreement. A positive correlation among all three analyzers existed; however, the analyzers do not yield directly interchangeable results.

Theileriosis in a reindeer (Rangifer tarandus tarandus) associated with a potentially novel Theileria sp.

A 5-year-old male neutered reindeer (Rangifer tarandus tarandus) from Missouri was presented with a 3-week history of anorexia, respiratory distress, lethargy, and weight loss. Blood smear review revealed that a small percentage of RBCs contained small (1-2 µm in length) pleomorphic piroplasms (signet ring, rod- or pear-shaped, and elongate forms) with an eccentric magenta nucleus and basophilic cytoplasm. Nested PCR to specifically amplify a portion of the piroplasm small subunit ribosomal RNA (SSU rRNA) gene was performed on DNA extracted from an EDTA specimen of whole blood. Subsequent sequence analyses showed similarity between the reindeer hemoparasite and Theileria spp SSU rRNA gene sequences in the GenBank database, with highest similarity to those of a Theileria sp in a White-tailed deer from North Texas (AY735132, AY735133). The reindeer and North Texas Theileria sp are genetically distinct from, albeit closely related to, the White-tailed deer Theileria sp (subsequently referred to as T cervi). To the authors' knowledge, this is the first identification of Theileria of this genotype in a reindeer. Historically, T tarandirangiferis infection was found with associated mortality in reindeer in Russia, but reports predate molecular characterization. Hence, the relationship of T tarandirangiferis with either T cervi or this agent remains unknown. T cervi is not typically pathogenic in White-tailed deer in the US unless the animal is immune-compromised by stress or disease; however, mortality from T cervi infection in reindeer has been reported.

Locally invasive lymphangiosarcoma in a young domestic shorthair.

A 2-year-old, female spayed, domestic shorthair cat presented to the University of Missouri-Veterinary Medical Teaching Hospital (UMC-VMTH) with an approximately 11-month history of fluid-draining pockets along her ventral thorax and axillae. The skin in these regions was erythematous, and multiple areas drained a serous to serosanguinous fluid. Fluid-filled, nodules formed along the ventrum, but these nodules disappeared as fluid drained spontaneously. Histologic assessment of skin biopsies revealed areas of vascular proliferation extending along the deep margin of the section and rare instances of invasion into the superficial dermis. These vascular channels were devoid of cells, lined by variably pleomorphic endothelial cells which had a low mitotic index. Based on the mild to moderate pleomorphism, positive staining with prospero-related homeobox gene-1 (PROX-1), and the locally aggressive nature of the tumor, a final diagnosis of lymphangiosarcoma was made.

Surgical management of orbital nodular granulomatous episcleritis in a dog.

A 27 kg, 6-year-old, male castrated German shorthaired pointer presented to the University of Missouri, Veterinary Teaching Hospital with the complaint of progressive exophthalmia of 2 years duration optical density (OD). Lack of retropulsion OD was noted on physical examination. Anterior segment examination OU and fundic examination OS did not reveal any abnormalities. Examination of the fundus OD revealed focal scleral indentation of the inferior nasal globe. The indentation changed location with globe movement OD. MRI and CT scan revealed a well-circumscribed, approximately 2 cm in diameter mass located caudal and ventral to the affected globe that appeared to communicate with the nictitating membrane with absence of any bony involvement. A modified lateral orbitotomy was recommended and performed to remove the orbital mass and nictitating membrane en-bloc. Histopathology and immunohistochemistry of the mass confirmed a diagnosis of nodular granulomatous episcleritis (NGE). Postoperatively, the dog developed absolute keratoconjunctivitis sicca (KCS). Examples of primary episcleral inflammation in the dog include diffuse episcleritis, NGE, nodular fasciitis, fibrous histiocytoma, proliferative conjunctivitis/keratoconjunctivitis, pseudotumor, and Collie granuloma. The etiology of these episcleral inflammations is presumed to be immune mediated. To our knowledge, this is the first report of NGE affecting the orbital region of a dog. Development of absolute KCS resulting from excision of the nictitating membrane is also supported by this case.

Hypermethylation of the DLC1 CpG island does not alter gene expression in canine lymphoma.

BACKGROUND: This study is a comparative epigenetic evaluation of the methylation status of the DLC1 tumor suppressor gene in naturally-occurring canine lymphoma. Canine non-Hodgkin's lymphoma (NHL) has been proposed to be a relevant preclinical model that occurs spontaneously and may share causative factors with human NHL due to a shared home environment. The canine DLC1 mRNA sequence was derived from normal tissue. Using lymphoid samples from 21 dogs with NHL and 7 normal dogs, the methylation status of the promoter CpG island of the gene was defined for each sample using combined bisulfite restriction analysis (COBRA), methylation-specific PCR (MSP), and bisulfite sequencing methods. Relative gene expression was determined using real-time PCR. RESULTS: The mRNA sequence of canine DLC1 is highly similar to the human orthologue and contains all protein functional groups, with 97% or greater similarity in functional regions. Hypermethylation of the 5' and 3' flanking regions of the promoter was statistically significantly associated with the NHL phenotype, but was not associated with silencing of expression or differences in survival. CONCLUSION: The canine DLC1 is constructed highly similarly to the human gene, which has been shown to be an important tumor suppressor in many forms of cancer. As in human NHL, the promoter CpG island of DLC1 in canine NHL samples is abnormally hypermethylated, relative to normal lymphoid tissue. This study confirms that hypermethylation occurs in canine cancers, further supporting the use of companion dogs as comparative models of disease for evaluation of carcinogenesis, biomarker diagnosis, and therapy.

Cytologic and histopathologic evaluation of extruded canine degenerate disks.

OBJECTIVE: To describe the cytologic and histopathologic appearance of degenerate disk material in dogs with Hansen type I intervertebral disk disease (IVDD). STUDY DESIGN: Case series. ANIMALS: Dogs (n=45) that had surgical intervention for Hansen type I IVDD (January-November 2007). METHODS: Impression smears and histopathologic sections were prepared from surgically removed degenerate disk material. All slides were evaluated for overall cellularity, quantity and attributes of extracellular matrix, types of cells present, and their cytomorphology. Histopathologic sections were also examined for presence of neovascularization and hemorrhage. RESULTS: Cytologically, 11 of 45 samples consisted of only extracellular matrix, 30 had evidence of inflammation, and 20 contained dysplastic spindloid cells. Histologically, hyaline cartilage predominated in 35 of 45 samples, fibrocartilage in 4, and spindloid cells in 6; 37 of 45 were inflamed, 37 were hemorrhagic, and 13 had neovascularization. CONCLUSIONS: The cytologic and histopathologic appearance of extruded degenerate disk material in dogs is variable and can include dysplastic spindloid cells. CLINICAL RELEVANCE: The variability in cytologic findings and frequent presence of dysplastic spindloid cells suggest that cytology alone may not be a reliable tool to differentiate degenerate canine disk material from a mesenchymal neoplasm.

Comparison of systemic toxicities of 177Lu-DOTMP and 153Sm-EDTMP administered intravenously at equivalent skeletal doses to normal dogs.

UNLABELLED: Bone-seeking radiopharmaceuticals have been used to effectively treat cancer arising from and metastasizing to bone in humans and dogs. The rate of complete tumor control is low, and the geographic distribution of available compounds is limited by their half-lives. This experiment was done to evaluate in normal dogs the toxicity of (177)Lu-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene phosphonate ((177)Lu-DOTMP) used as a potential therapeutic radiopharmaceutical. METHODS: Four normal purpose-bred dogs were administered (177)Lu-DOTMP at a dose of 8.14 MBq/kg and monitored for 84 d for evidence of toxicity in the bone marrow and vital organs. RESULTS: No statistically significant alterations in the biochemical profile, white blood cell count, or platelet count were observed in any dog. Very mild decreases in the red cell count were seen on day 84. No microscopic evidence of toxicity was present at necropsy. CONCLUSION: The dogs receiving (177)Lu-DOTMP tolerated the administration and the effects of the compound without apparent clinical toxicity. The results of this experiment support the further evaluation in tumor-bearing dogs of (177)Lu-DOTMP as a potential therapy for metastatic bone cancer and primary bone tumors in humans and dogs.

Physical map and genome sequencing survey of Mycoplasma haemofelis (Haemobartonella felis).

Mycoplasma haemofelis is an uncultivable red-cell pathogen of cats. Isolated M. haemofelis DNA was used to create a bacterial artificial chromosome library and physical map. Random sequencing of this material revealed 75 genes that had not been previously reported for M. haemofelis or any other hemotrophic mycoplasma.