Acanthomatous ameloblastoma with atypical foci in five dogs.

Acanthomatous ameloblastoma is a common, locally invasive, nonmetastasizing tumor of the canine oral cavity. The long-term prognosis for canine acanthomatous ameloblastoma is good if complete excision can be achieved, usually by maxillectomy or mandibulectomy. A variant of acanthomatous ameloblastoma with atypical foci was noted in 5 dogs. There was no age, breed, or sex predisposition. Atypical cells were pleomorphic with a high mitotic rate. They were immunohistochemically negative for cytokeratin, vimentin, melan A, PNL2, CD3, Pax5, CD18, chromogranin A, and synaptophysin. Ultrastructurally, the atypical cells had modest amounts of electron-lucent cytoplasm, abundant rough endoplasmic reticulum, zonula adherens junctions, cleaved or irregular nuclei, and occasional cytoplasmic structures consistent with secretory granules or lysosomes. Complete excision was achieved by maxillectomy or mandibulectomy in 3 dogs; the lesion was incompletely excised in 2 dogs. No ancillary therapy was elected in any patient. No local recurrence or distant metastasis was reported in any case. One patient died of heart failure 20 mo following complete excision; all other patients were alive at last follow-up (average follow-up: 18.8 mo, range: 6-30 mo). The histogenesis of the atypical foci is unclear, but atypical foci within acanthomatous ameloblastoma do not appear to be associated with metastasis or with a poor prognosis relative to acanthomatous ameloblastoma with typical histologic morphology.

Classification and clinical features in 88 cases of equine cutaneous lymphoma.

Equine cutaneous lymphoma is an uncommon disease that can present with variable clinical signs, immunosuppression, and rapid systemic disease progression. Various subtypes of equine lymphoma have been described and classified according to a veterinary adaptation of the World Health Organization classification system, but little data is available regarding the association between lymphoma subtypes and epidemiological criteria and/or clinical outcome. The objective of the current study was to classify previously diagnosed cases of equine cutaneous lymphoma and correlate subtypes with clinical data to investigate epidemiological trends and prognostic implications. Results from the study confirm T-cell-rich, large B-cell lymphoma (TCRLBCL) as the predominant subtype in equine cutaneous lymphoma. Cutaneous T-cell lymphoma (CTCL) was the second most common phenotype in the current study. To the authors' knowledge, a description of the morphological and immunohistochemical features of CTCL in horses, an epitheliotropic neoplasm similar to the cutaneous epitheliotropic lymphoma variant (mycosis fungoides) observed in human beings and canids, has not been previously described. Less common lymphoma subtypes identified in the study include diffuse large B-cell lymphoma and anaplastic large T-cell lymphoma. Quarter Horses almost exclusively developed TCRLBCL, while the frequency of CTCL was increased significantly in Thoroughbreds compared with other breeds. TCRLBCLs more frequently presented as multiple masses while CTCLs were more often solitary nodules. When multiple regions of the body were affected, 100% of cases were TCRBCL. Finally, there was an observable trend for longer survival in cases of TCRLBCL without local recurrence, suggesting adequate surgical excision may be an effective treatment modality.

Subcutaneous fluid port-associated soft tissue sarcoma in a cat.

A 20-year-old male castrated domestic longhair cat was evaluated for assessment of its chronic kidney disease (CKD) and a non-healing ulcerated mass at the site of a previously placed and subsequently removed GIF tube. The cat had been diagnosed with CKD 10 years prior and two GIF tubes had been placed over a 5-year period, the second of which was associated with secondary infection. Biopsy of the non-healing ulcerated mass was consistent with grade 2 soft tissue sarcoma. At necropsy there was a discrete, serpentine, subcutaneous mass measuring approximately 8 mm in diameter that extended approximately 20 cm along the dorsum to the caudal thorax, following the path of the GIF tube, from the main intrascapular, ulcerated mass where the fluid port injection site was located. This is the first report of a fibrosarcoma arising at the site of a subcutaneous fluid port in a cat. Although the cat's owners were pleased with the 4 years of quality of life provided by this device, this complication should be considered when a decision to place ports for long-term management of disease is made.

Biaryl piperidines as potent and selective delta opioid receptor ligands.

The design and synthesis of novel opiates are reported. Based on the message-address principle a novel class of 4,4- and 3,3-biaryl piperidines was designed and synthesized. Biological evaluation confirmed that these compounds exhibit high affinity and selectivity for the delta opioid receptor. Key structure-activity relationships that influence affinity, selectivity, functional activity and clearance are reported.

Specific enzymatic diagnosis and ultrastructural analysis of peripheral leukocytes in infantile form of Niemann-Pick sphingomyelinosis.

Acute infantile type of Niemann-Pick sphingomyelin lipidosis has been published concentrating to the morphological and biochemical specific enzyme investigations. The electronmicroscopical study of the peripheral lymphocytes proved to be of diagnostic value for lysosomal lipidoses.