Calcinosis circumscripta is an uncommon syndrome of ectopic idiopathic, dystrophic, metastatic or iatrogenic mineralization characterized by deposition of calcium salts in soft tissues. This paper is a retrospective study of 77 canine cases. The age of dogs in the study varied from 4 months to 15 years and 55% were <1 year old, 74% <2 years old and 88% <4 years old. Several pure and mixed, typically large breed dogs were affected so that 28.6, 13 and 9% were German Shepherd, Rottweiler and Labrador Retriever respectively. The size of lesions varied from 2 mm to 13 cm in diameter but most lesions were between 0.5 cm and 3 cm in diameter. Lesions were solitary in 82% of the affected dogs, and occurred most commonly on the hind feet (50%) and tongue (23%). With multiple lesions there was no apparent body symmetry. Microscopically, most lesions were well-defined single or multiple variably sized aggregates of amorphous to granular, lightly to darkly basophilic material with or without peripheral granulomatous reaction and surrounded by varying amounts of fibrous connective tissue. Additionally, three small nodular masses in the wall of the jejunum of a dog were diagnosed as calcinosis circumscripta. This is the first reported case of idiopathic intestinal calcinosis circumscripta in the dog.

Abstract. Fifty-six dogs from St. John's, Newfoundland, Canada, were evaluated for Angiostrongylus vasorum infection. Small numbers of nematodes were found within pulmonary arteries of 6 dogs. Larvae were identified in fecal samples in 2 of 6 dogs. All 6 dogs had multifocal granulomatous pneumonia and sometimes foci of chronic thrombosis, which varied from very mild to severe. One dog had extensive pulmonary lesions resulting in cor pulmonale. Right heart failure was characterized by right ventricular hypertrophy, hepatic congestion, ascites, and hydrothorax. Microscopically, in most cases, eggs, larvae, and sometimes intravascular adults, were present within lung tissue sections. Small foci of granulomatous inflammation with and without larvae were present in kidney and brain in 4 dogs. An additional dog, diagnosed antemortem with angiostrongylosis via fecal examination, was also examined. Pathological findings consisted of severe pyogranulomatous interstitial pneumonia with myriad eggs, larvae, and numerous intravascular pulmonary adult nematodes with extensive arterial thrombosis. Five hundred and seventy-two adult worms were removed from pulmonary arteries. Foci of granulomatous inflammation, often associated with larvae and/or eggs, were present in tracheobronchial lymph nodes, adrenal gland, brain, and kidneys. Severe seizuring noted antemortem was attributed to several large, discrete areas of acute hemorrhagic infarction within the cerebrum and cerebellum. Natural A. vasorum infection in domestic dogs in eastern Newfoundland causes lung pathology of variable severity, which in some cases, may progress to cor pulmonale and which may be associated with extrapulmonary lesions and clinical signs.

Tissue samples and feces were collected from a dead, adult female coyote (Canis latrans) found at the side of the road in late March 2003 in the Avalon Peninsula region of Newfoundland, Canada. The coyote apparently died of vehicular-related trauma. Samples of lung, brain, heart, liver, and kidney were fixed in formalin and submitted for histologic examination. The entire remaining lung and heart also were submitted for examination. The coyote was diagnosed with moderate, multifocal, granulomatous interstitial pneumonia with eosinophilic vasculitis and many intralesional nematode eggs, larvae, and occasional intravascular adult worms. Adult nematodes recovered from the pulmonary arteries were identified as Angiostrongylus vasorum. Small foci of granulomatous inflammation, often containing nematode eggs and larvae, were scattered in the brain and kidney. To our knowledge, this is the first report of A. vasorum infection in a coyote from the only endemic area of infection in North America.

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A 4.5-year-old Quarter Horse gelding was referred for evaluation of a swollen right hind leg of 3 weeks duration, which had occurred after exercise. Lameness was not observed and cold hydrotherapy had resulted in little improvement. Two weeks before presentation, the gelding developed a swelling over the left zygomatic arch for which a tentative diagnosis of abscessation was made. However, the lesion was unresponsive to antibiotics, became pruritic, ulcerated, and exuded serosanguinous fluid. Two days before presentation, dexamethasone powder a was prescribed to treat the leg swelling. On the day of presentation, the gelding also developed a swelling overlying the xiphoid process and a swelling on the right lateral abdomen.At presentation, the gelding weighed 546 kg and had normal vital signs. The right hind fetlock was swollen circumferentially from the distal third of the metatarsus to the pastern. The swelling was warm, firm, and nonpitting. The gelding was grade 1/5 lame in the affected limb.1 The mass (5 cm diameter, 2 cm depth) over the zygomatic arch was firm, ulcerated, and immoveable. The xiphoid process swelling (1 cm diameter, 1 cm depth) was soft, nonfluctuant, and nonmobile. The soft tissue swelling (15 cm diameter, 1 cm depth) on the right lateral abdomen resembled cutaneous edema.Biochemical and hematologic values were within reference intervals except for mild eosinophilia. Radiographs of the right hind fetlock revealed a discrete osteophyte on the dorso-medial aspect of the 1st phalanx. Skull radiographs showed a discrete soft tissue swelling surrounding the left zygomatic arch.Ultrasonography of the right metatarsal area revealed thickening of the subcutaneous tissues (1.1 cm depth) and distention (3.5 cm diameter, 1.5 cm depth) of the digital flexor tendon sheath with anechoic fluid at the level of the fetlock and pastern.Histopathologic evaluation of a 5-mm-diameter punch biopsy from the mass on the head revealed a poorly defined tumor involving the subcutis and deep dermis. It was composed of multiple, densely cellular islands and nests of pale, neoplastic round cells embedded in large amounts of dense fibrous stroma. Mild-to-moderate infiltrates of eosinophils surrounded these neoplastic aggregates. Tumor cells had pale eosinophilic cytoplasm, uniform oval nuclei with finely stippled chromatin, and inapparent to single small nucleoli. Toluidine-blue staining revealed many fine metachromatic cytoplasmic granules. No mitotic figures were observed. This mass was diagnosed as a cutaneous mast cell tumor. Histopathologic evaluation of two 5-mm-diameter punch biopsies of the mass overlying the xiphoid process revealed marked subcutaneous fibrosis containing mild infiltrates of eosinophils with fewer lymphocytes and plasma cells. There was no evidence of neoplasia. The subcutis contained rare discrete aggregates of cell debris, amorphous hypereosinophilic material, and occasional hyalinized fragmented collagen fibers surrounded by a rim of epithelioid macrophages admixed with eosinophils consisten...

KO mice showed reduced expression of MMPs. This correlates well with our finding that stimulation of human OA synovium with WISP1 led to increased MMP expression. TGF-b signaling via Smad 2/3 is crucial for maintaining the homeostasis of the cartilage, while signaling via Smad 1/5/8 is associated with chondrocyte hypertrophy. In order to determine if WISP1 affects TGF-b signaling, we stained WT and WISP1 depleted joints for phosphorylated Smad 2/3. We found that Smad 2/3 signaling was increased in the WISP1 KO mice, suggesting that increased WISP1 expression during OA decreases Smad 2/3 signaling. In addition, recent data showed that WISP1 might not only act as a downstream target of canonical Wnt signaling, but could also regulate the accumulation of b-catenin, and positively control canonical Wnt signaling, further aggravating the OA pathology. To investigate if this mechanism was present in experimental OA, we stained our sections for b-catenin and found that WISP1 depleted tissues indeed have decreased levels of b-catenin accumulation in the cartilage. Conclusions: Overexpression of WISP1 in the synovium and cartilage, as is found in OA conditions, may play an important role in OA pathology via modulation of TGF-b signaling and via a positive feedback mechanism on canonical Wnt signaling. Because Wnt signaling is both extremely complex and tightly regulated and can affect many biological processes, upstream targeting of Wnt signaling is likely to produce undesired side-effects. Specific downregulation of WISP1 may more specifically target the pathological events that take place during OA without interfering with normal processes.

Abstract. This report details 2 outbreaks of dermatophytosis in 2 different mink ranches. On the first farm, only kits were affected, while on the second farm, small numbers of adults were infected. Affected mink were otherwise clinically healthy and in good body condition. Three animals were euthanized and submitted for autopsy. Grossly, mink exhibited locally extensive to coalescing areas of crusting alopecia but no other significant gross lesions in internal organs. Microscopically, skin lesions were characterized by chronic hyperplastic dermatitis with folliculitis, furunculosis, occasional intracorneal pustules, and large numbers of intrafollicular fungal arthrospores and hyphae. The dermatophyte was cultured and identified as Trichophyton equinum based on molecular barcoding of the internal transcribed spacer region of the ribosomal DNA gene.

Summary A 6‐month‐old Standardbred weanling presented with acute non‐ambulatory tetraparesis. Cranial nerve examination was normal and neuroanatomic localisation suggested there was a focal C1‐C5 spinal cord lesion. Post‐mortem examination identified a cervical vertebral epidural haematoma at the level of C2‐C3 causing spinal cord compression and neurological deficits. Histological examination determined the haematoma was several weeks old making the lesion chronic. Since the clinical progression was acute, this suggests an acute on chronic pathophysiology. Even with no history of trauma, an epidural haematoma should be on the differential list in young horses with acute tetraparesis.