Variation in E(rns) viral glycoprotein associated with failure of immunohistochemistry and commercial antigen capture ELISA to detect a field strain of bovine viral diarrhea virus

Bovine viral diarrhea virus (BVDV) affects cattle populations causing clinical signs that range from subclinical immunosuppression to severe reproductive and respiratory problems. Detection and removal of persistently infected (PI) calves is the single most important factor for control and eradication of BVDV. Current testing strategies to detect PI calves rely heavily on immunohistochemistry (IHC) and a commercially available antigen capture ELISA (ACE) assay. These viral assays depend on 1 or 2 monoclonal antibodies which target the E(rns) glycoprotein of BVDV. The sensitivity and specificity of these two tests have been reported previously. The purpose of this research was to characterize a strain of BVDV (AU501) that was undetectable using IHC and ACE based on a single monoclonal antibody, but was consistently detected in samples from a Holstein steer using virus isolation and PCR testing. Sequencing of this AU501 viral isolate revealed a unique mutation in the portion of the genome coding for the E(rns) glycoprotein. This unique field strain of BVDV demonstrates the risk of relying on a single monoclonal antibody for detection of BVDV. Multiple testing strategies, including polyclonal or pooled monoclonal antibodies that detect more than one viral glycoprotein may be necessary to detect all PI calves and facilitate eradication of BVDV.     

Episodic blindness and ataxia in a horse with cholesterinic granulomas

An 11‐year‐old Oldenburg mare presented following three episodes of acute, transient blindness, ataxia, and disorientation within the preceding 7 months. Clinical improvement, including return of vision, occurred within 1 week of initiating corticosteroid therapy for each of the three episodes. However, mild right‐sided miosis was a consistent finding on ophthalmic examinations. Routine clinicopathologic testing revealed no significant abnormalities, and testing of cerebral spinal fluid for selected infectious diseases was unrewarding. Computed tomography of the brain demonstrated a hyperattenuating mass with peripheral mineralization in the rostroventral aspect of each lateral ventricle. The mare was euthanized due to a guarded to poor prognosis. On histopathology, the masses consisted of clusters of cholesterol clefts admixed with leukocytes, mineral deposits, and connective tissue. Cholesterinic granulomas of the lateral ventricles and hydrocephaly were diagnosed. Cholesterinic granulomas should be considered a differential diagnosis in horses presenting for intermittent blindness.     

Expression of vascular endothelial growth factor in canine oral malignant melanoma

Serum, plasma and tissue expression of vascular endothelial growth factor (VEGF) was measured in 20 dogs previously diagnosed histologically with oral melanoma. The concentrations of VEGF in serum and plasma were significantly higher in dogs with melanoma than in a control population (P ≤ 0.002). Concentrations of VEGF in the serum and plasma of dogs with melanoma were highly correlated (r = 0.867). Ninety‐five per cent of melanoma tissues expressed VEGF. Two staining patterns were detected: diffuse and granular cytoplasmic staining. High blood concentrations of VEGF were correlated to a shorter survival time in dogs receiving definitive therapy (P = 0.002). Survival times were significantly longer in dogs receiving definitive therapy versus palliative therapy (median 496 versus 97 days, P = 0.007). Blood concentrations of VEGF were associated with stage (P < 0.05). Dogs with oral melanoma have increased serum, plasma and tissue concentrations of VEGF. Increased expression of VEGF may be a reasonable target for future therapy of canine oral melanoma.     

Serum 17-alpha-hydroxyprogesterone and corticosterone concentrations in dogs with nonadrenal neoplasia and dogs with suspected hyperadrenocorticism

OBJECTIVE: To assess serum 17-alpha-hydroxyprogesterone (17OHP) and corticosterone concentrations in dogs with nonadrenal neoplasia and dogs being screened for hyperadrenocorticism. DESIGN: Prospective study. ANIMALS: 16 clinically normal dogs, 35 dogs with nonadrenal neoplasia, and 127 dogs with suspected hyperadrenocorticism. PROCEDURE: ACTH stimulation tests were performed in all dogs. Baseline serum cortisol and corticosterone concentrations were measured in the healthy dogs; baseline serum cortisol concentration and ACTH-stimulated cortisol, corticosterone, and 17OHP concentrations were measured in all dogs. Endogenous plasma ACTH concentration was also measured before administration of ACTH in dogs with neoplasia. RESULTS: In 35 dogs with neoplasia, 31.4% had high serum 17OHP concentration and 22.9% had high serum corticosterone concentration. Of the 127 dogs with suspected hyperadrenocorticism, 59 (46.5%) had high ACTH-stimulated cortisol concentrations; of those, 42 of 59 (71.2%) and 32 of 53 (60.4%) had high serum 17OHP and corticosterone concentrations, respectively. Of dogs with serum cortisol concentration within reference range after ACTH administration, 9 of 68 (13.2%) and 7 of 67 (10.4%) had high serum 17OHP and corticosterone concentrations, respectively. In the dogs with neoplasia and dogs suspected of having hyperadrenocorticism, post-ACTH serum hormone concentrations were significantly correlated. CONCLUSIONS AND CLINICAL RELEVANCE: Serum concentrations of 17OHP or corticosterone after administration of ACTH may be high in dogs with nonadrenal neoplasia and no evidence of hyperadrenocorticism. Changes in serum 17OHP or corticosterone concentrations after administration of ACTH are proportionate with changes in cortisol concentration.     

Cation-ratio and accelerator radiocarbon dating of rock varnish on mojave artifacts and landforms

The first accelerator radiocarbon dates of rock varnishes are reported along with potassium/argon ages of lava flows and conventional radiocarbon dates of pluvial lake shorelines, in an empirical calibration of rock varnish K(+) + Ca(2+)/Ti(4+) ratios with age in the Mojave Desert, eastern California. This calibration was used to determine the cation-ratio dates of 167 artifacts. Although cation-ratio dating is an experimental method, some dates suggest human occupation of the Mojave Desert in the late Pleistocene.     

Immunoglobulin structure: variation in the sequence of Bence Jones proteins

Analysis of the amino acid sequence of one Bence Jones protein is almost comtplete. Many points of interchange occur in the amino terminal. portion of the molecule relative to partial-sequence data for other proteins. Most, but not all, are, compartible with one-step mutations. Such structural variation in immunoglobulin light chains may result from many related genes.     

Phacofragmentation and aspiration for cataract extraction in dogs: 56 cases (1980-1984)

Fifty-six cases of cataract removal in dogs by phacofragmentation and aspiration were reviewed. Improvement of vision was detected in the immediate postoperative period in 53 (94.6%) of 56 dogs. Vision was present in 25 (85.2%) of 29 dogs evaluated at 2 years after surgery, and in 5 (71.4%) of 7 dogs evaluated 4 years after surgery. Reasons for failure of visual improvement and complications in visual eyes were related primarily to development of postoperative anterior uveitis. Age of the dog at surgery was not a significant factor in the restoration of vision.     

Gastroprotectants in small animal veterinary practice – a review of the evidence. Part 1: cyto‐protective drugs

Diverse drugs with presumed cytoprotective effect have been used therapeutically in small animal veterinary practice for various gastro‐intestinal conditions such as oesophagitis, gastric ulceration, gastritis or chronic gastro‐enteropathies. Their efficacy has been doubted in human medicine, raising similar questions in the veterinary field. The aim of this review was to assess the current evidence on the efficacy and safety of these drugs in dogs and cats. Through a systematic review of the literature, we identified 37 articles on the use of misoprostol, sucralfate and other gastroprotectants in dogs and cats. There was evidence to support use of misoprostol in the prevention of aspirin‐induced gastroduodenal mucosal injury in dogs, and for use of sucralfate in the prevention of acid‐induced oesophagitis in cats. However, the overall quality of evidence supporting the use of these drugs in small animal patients was poor. In contrast, there was evidence of important adverse effects, especially drug interaction and gastro‐intestinal signs. We therefore recommend prescribing these drugs with caution until further well‐conducted studies reveal a useful gastroprotectant effect.