Histopathological and immunohistochemical analysis of the endocrine and exocrine pancreas in twelve cattle with insulin-dependent diabetes mellitus (IDDM).

Histological and immunohistochemical studies were carried out on the pancreas of twelve cattle of insulin-dependent diabetes mellitus (IDDM). They showed clinical signs such as persistent hyperglycemia, glycosuria and decreased glucose tolerance, and some cases accompanied with or without ketonuria. Histopathologically, eight cattle were diagnosed as chronic IDDM, while others were acute IDDM. The most characteristic lesions of the pancreas in chronic IDDM showed a decrease in the size and number of pancreatic islets, interlobular and interacinar fibrosis, mild lymphocytic insulitis, and vacuolation of a few islets. Almost all cells in the atrophied islets had a small amount of ungranulated cytoplasm. Immunohistochemical examination revealed that the atrophied islet cells did not react to anti-insulin antibody, but occasionally reacted to anti-glucagon or somatostatin antibodies. A few solitary islets with mild lymphocytic infiltration, necrotic islets with occasional calcification, and atrophied islets with mild fibrosis were also observed. A few islets consisted of many islet cells with vacuolated cytoplasm including a small number of insulin-positive granules. Accumulation of glycogen granules was occasionally observed in these islets. Islet fibrosis was due to the proliferation of collagen fibers reactive to both anti-collagen type I and type III antibodies. In acute IDDM, the major islets consisted of the cells with vacuolated cytoplasm indicating the degranulation of islet cells. These islets contained many islet cells with shrunken cytoplasm and karyorrhectic nuclei. Lymphocytic infiltration was frequently observed in the islets which consisted of many islet cells having karyorrhectic nuclei and vacuolated and severely degranulated cytoplasm. Immunohistochemically, islet cells with vacuolated cytoplasm had a small amount of insulin-positive granules, suggesting severe degranulation of beta-cells. An increase in acinar islet-cells and proliferation of ductal epithelial cells showing insulin-immunoreactivity were observed. Bovine IgG-immunoreactive islet cells were frequently seen in the vacuolated islets. In summary, pathological observations suggested that beta-cells were being destroyed by an inflammatory process which selectively affected the pancreatic islets. Lymphocytic insulitis and anti-bovine immunoreactive islet cells were thought to be the most significant changes in determining the etiology and pathogenesis of bovine IDDM, and suggested their role in anti-islet autoimmunity in this form of diabetes.     

Large granular lymphocytic leukemia in a mixed breed dog

A mixed breed dog was diagnosed with large granular lymphocytic leukemia. Immunophenotypic analysis indicated the lymphocytes were CD3+, CD8+ T cells expressing the alpha beta T cell receptor and a leukointegrin, alpha d. Chemotherapy and splenectomy resulted in an initial reduction in the lymphocyte count.     

Detection and identification of Mycoplasma from bovine mastitis infections using a nested polymerase chain reaction.

A polymerase chain reaction (PCR) test was compared with culture for the detection and diagnosis of bovine Mycoplasma intramammary infection. The PCR test was applied to 24-hour Mycoplasma enrichment cultures of milk from cows with suspected mastitis and from bulk tank milk. In comparison to culture, the sensitivity and specificity of the PCR method were 96.2% and 99.1% for individual cow milk and 100% and 99.8% for the bulk tank milk, respectively. However, in discrepant cases where PCR was positive and culture was negative, the PCR test was correct; subsequent PCR tests and culturing of the individual cow's milk yielded positive results. The PCR test simultaneously detected and differentiated among 11 bovine Mycoplasma species.     

A Comparison of the Plasma Fructose Concentrations in Dogs and Cats and Changes in the Fructose Concentrations in Dogs Following Intravenous Administration of Fructose

The plasma concentrations of fructose, glucose, free fatty acids (FFA) and triglycerides (TG) were measured in dogs and cats. Changes in these concentrations were investigated in dogs by an intravenous fructose tolerance test (IVFTT) at a dose of 0.1 g/kg body weight. Fructose concentrations in the plasma of dogs were significantly higher than those of cats. There was no significant difference in plasma glucose concentrations between dogs and cats. Plasma FFA concentrations decreased and TG concentrations increased after feeding in both dogs and cats. During the IVFTT, the plasma fructose concentrations in the dogs increased rapidly to a peak by 2 min and then decreased to half of the peak by 5 min after the administration of fructose. Administration of fructose resulted in an increase in the plasma TG concentrations and reduced plasma FFA concentrations in the dogs. Only 4% of the administered fructose was detected in the urine of dogs following IVFTT. Plasma fructose was considered to be rapidly absorbed and metabolized in both dogs and cats. However, as with glucose metabolism, there appear to be some differences in fructose metabolism between dogs and cats.     

A retrospective study of canine house soiling: diagnosis and treatment

A retrospective study was conducted to determine the relative frequency and type of elimination problem seen in dogs at a university referral practice and to evaluate the efficacy of the suggested treatments. Cases presented to the Animal Behavior Clinic at Cornell University between 1987 and 1996 were reviewed. Of 1,173 cases, 105 (9%) were house-soiling cases. Of these cases, the authors obtained outcome information from 70. Within the diagnosis of house soiling, incomplete housebreaking (n=59; 84%) were the most frequent referral cases, of which 48 cases (81%; 95% confidence interval, 69% to 90%) improved. Separation anxiety was considered the second most common underlying cause (n=27; 39%), of which 85% (n=23; 95% confidence interval, 66% to 96%) improved. Behavior modification was the most often suggested treatment (n=58), with 48 (83%) cases improving. Behavior modification consisted of accompanying the dog to the preferred elimination area, rewarding the dog for eliminating there, and punishing the dog only when caught in the act of house soiling. These results suggest that correct house training, behavior modification involving positive reinforcement, and appropriate punishment are essential to diminish house-soiling problems in dogs.     

Analysis of gene expression of prostaglandin EP4 receptor in canine osteosarcoma

In many human cancers, the expression of the prostaglandin receptor EP4 (EP4R) is associated with the development of malignancy and a poor prognosis. The expression of EP4R has not yet been evaluated in canine tumors. The objective of this study was to characterize the messenger RNA (mRNA) expression of EP4R in canine osteosarcoma (OSA). Gene expression of EP4R was evaluated using RNA in-situ hybridization (RNAscope). In all canine OSA samples evaluated, strong universal positive expression of EP4R was identified. Gene expression was significantly higher in OSA tissue samples than in normal nasal turbinate bone, possibly implicating EP4R in the pathogenesis of canine OSA.     

Monoclonal Antibody C219 Immunohistochemistry Against P-Glycoprotein: Sequential Analysis and Predictive Ability in Dogs With Lymphoma

In the present study, the prevalence of positive staining for P-glycoprotein using C219 monoclonal antibody was assessed in 58 tissue samples of high-grade lymphoma from dogs before initiation of chemotherapy. Samples were also evaluated at relapse in 22 dogs, at necropsy in 34 dogs, and at all 3 times in 15 dogs. The frequency of positive staining was significantly higher than that found prior to the initiation of chemotherapy at the following times: relapse ( P = .0001), necropsy ( P < .0001), and both relapse and necropsy ( P < .001, sequential data). The frequency of positive staining prior to the initiation of chemotherapy was significantly inversely related to remission ( P < .001) and survival times ( P = .0012). Similarly, when populations below and above the median initial C219 score were compared with respect to remission and survival times, the population with scores greater than the median had significantly lower remission ( P < .001) and survival ( P = .008) times, respectively. The frequency of positive staining determined at relapse was significantly inversely related to the time from relapse to death ( P = .0102). Similarly, when populations below and above the median relapse C219 score were compared with respect to the time from relapse to death, the population with C219 scores greater than the median had a significantly lower time from relapse to death ( P = .006). It appears that this immunohistochemical methodology may be used as a predictor of remission time, survival time, and the time from relapse to death. Additional studies are required to confirm the usefulness of C219 as a true marker of P-glycoprotein and to evaluate P-glycoprotein as a useful prognostic factor in dogs with lymphoma.     

Spontaneous and experimental glycoprotein storage disease of goats induced by Ipomoea carnea subsp fistulosa (Convolvulaceae)

Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine.