A case of protein-losing enteropathy treated with methotrexate in a dog

A 9-year-old female Pug was presented to us with chronic diarrhea. Hematologic findings indicated severe hypoproteinemia and hypoalbuminemia, and endoscopy revealed severe edema of the duodenal mucosa. Based on these results and on additional histopathological findings, we made a diagnosis of protein-losing enteropathy caused by lymphocytic-plasmacytic enteritis with lymphangiectasia. The dog was initially treated with prednisolone and cyclosporine. This treatment regimen was not effective. However, when methotrexate was substituted for cyclosporine, progress was obtained and the diagnosis was confirmed.     

Spontaneous Erythroid Leukemia in a 7-Week-Old Crl:CD (SD) Rat

A young male Crl:CD (SD) rat with erythroid leukemia that presented with emaciation, abdominal distension and a pale visible mucosal membrane was euthanized at 7 weeks of age. At necropsy, enlargement of liver, spleen and pancreatic lymph node was noted. Analysis of blood smear samples revealed many mono- or binucleated erythroblasts that had PAS-positive vacuoles in the cytoplasm. Histopathologically, neoplastic proliferation of atypical cells was observed in the hepatic sinusoids, splenic red pulp, bone marrow, pancreatic lymph node, kidney and lung. Neoplastic cells showed a round to spindle shape, and some neoplastic cells had deeply stained small nuclei and small cytoplasms and resembled erythroblasts. Immunohistochemically, many neoplastic cells were positive for hemoglobin. To our knowledge, this is the first report of erythroid leukemia in a rat of this age. The observed features were similar to those of pure erythroid leukemia in humans.     

Regulation of secondary follicle growth by theca cells and insulin-like growth factor 1

Ovaries contain follicles at various stages of development, including primordial, primary, secondary, antral and Graafian follicles. Although the growth of these follicles is controlled to maintain regular ovulation, the mechanism through which this occurs remains unclear. In our study, we found that the growth rate of cultured secondary follicles separated from mice ovaries differed between follicles. After 4 days of culture, the size of some secondary follicles was markedly increased, while that of others had either slightly increased, remained unchanged or shrunk. We compared the expression levels of growth factors between these secondary follicles and found that the growth rate of cultured secondary follicles correlated with the expression level of insulin-like growth factor 1 (Igf1) mRNA. Igf1 mRNA expression level in secondary follicles containing theca cells was higher than that in secondary follicles without theca cells, and the granulosa cell proliferation around follicles containing theca cells was increased. Furthermore, an IGF1 inhibitor also inhibited the granulosa cell proliferation, and administration of IGF1 to secondary follicles without growth promoted granulosa cell proliferation. These results indicated that the theca cells of secondary follicles induced the expression of IGF1 and promoted the follicle growth.     

CD44 expression in the bile duct epithelium is related to hepatic fibrosis in nonalcoholic steatohepatitis rats induced by a choline-deficient,methionine-lowered, L-amino acid diet

Nonalcoholic steatohepatitis is a lifestyle-related disease and an increasing threat worldwide. Hepatic fibrosis, which results from chronic hepatic diseases including nonalcoholic steatohepatitis, is closely correlated with mortality among hepatic lesions, such as steatosis and inflammation. Thus, it is important to identify factors that can serve as diagnostic and therapeutic targets for hepatic fibrosis. In this study, we examined the function of CD44 in the development of hepatic fibrosis in choline-deficient, methionine-lowered, L-amino-acid diet-fed rats, especially with respect to the proliferation of bile duct epithelium. Male Fischer 344 rats were fed a choline-deficient, methionine-lowered, L-amino-acid diet for 2, 4, 13, or 26 weeks. This diet decreased the body weight; increased the levels of serum parameters indicating liver injury, such as aspartate and alanine aminotransferase; upregulated inflammation- and fibrosis-related gene expression in the liver; and resulted in the development of hepatic lesions, including fatty changes in hepatocytes, inflammatory cell infiltration, and fibrosis. Hepatic hyaluronan was synthesized and deposited in the liver tissue. The expression of both CD44 mRNA and protein was significantly increased throughout the experimental period. CD44 protein was observed in some of the bile duct epithelium, around which hyaluronic acid was deposited, and these bile duct lesions were concordant with the area of hepatic fibrosis. Thus, CD44 expressed in the bile duct epithelium may be a target for controlling nonalcoholic steatohepatitis-related hepatic fibrosis.     

Molecular cloning and sequencing of feline CD7

Human CD7 is one of the earliest molecules to appear in T cell development. In this study, putative feline CD7 cDNA was identified based on its similarities with human and mouse CD7 genes. The feline CD7 cDNA contained an open reading frame consisting of 630 nucleotides. The amino acid sequence of feline CD7 had 47.7% identity with that of human CD7, and 52.9% with that of mouse CD7. In addition, the feline CD7 protein fused with histidine tag was expressed in 293T cells. The expression was confirmed by indirect immunofluorescence assay.     

A case of spontaneous Zymbal’s gland carcinoma with lung metastasis in an aged Fischer 344 rat

Zymbal’s gland neoplasms are induced in rats through the administration of various carcinogens, but spontaneous neoplasia is rare. This report describes a spontaneous Zymbal’s gland carcinoma with lung metastasis found in an aged male Fischer 344 rat. Macroscopically, the dome-like tumor nodule, approximately 30 mm in diameter with ulceration, was located near the ear canal of the rat. No healthy tissue or structure of Zymbal’s gland was identified on the corresponding side, while the normal salivary glands and a lacrimal gland were observed. Histologically, a large part of the tumor mass was occupied by poorly differentiated neoplastic cells, the shapes of which were oval to polygonal or fusiform. Additionally, clusters of sebaceous-like foamy cells and squamous metaplasia with prominent keratinization were observed. Tumor cells were found to metastasize to the lung; these cells displayed histological similarities, including a sebaceous gland-like pattern, to those in the primary site. The tumor cells were immunohistochemically positive for cytokeratin AE1/AE3 or vimentin but negative for CD68, S100, α-smooth muscle actin, von Willebrand factor, and desmin. Our results indicate that the tumor was a poorly differentiated Zymbal’s gland carcinoma with lung metastasis.     

The effect of 7.2% hypertonic saline solution on the duration of sodium gradient between the cerebrospinal fluid and the venous circulation in the dog

To determine the duration of water movement from cerebrospinal fluid (CSF) into venous blood by the infusion of 7.2% hypertonic saline solution (HSS), the sodium gradient between venous blood and CSF were examined. Venous sodium concentrations remained higher than that in CSF for duration of 60 min following HSS infusion. By 90 min, the CSF sodium concentration reached the equilibrium with venous sodium concentration. Those data suggests that the duration of time during which water moved from CSF into capillaries in brain by the gradient of sodium concentration was less than 90 min.     

Effects of feeding calves genetically modified corn bt11: a clinico-biochemical study

Genetically modified corn Bt11 is insect-resistant and expresses Cry1Ab toxin, an insecticidal protein, in kernels. Although Bt11 corn is considered safe based on animal performance, there are no reports available on the clinico-biochemical effects of feeding it to cattle. In this study, we evaluated the effects of feeding Bt11 to calves, using blood and ruminal clinico-biochemical parameters. Our three-month-long feeding experiment demonstrated that calves (n=6), fed with a ration containing 43.3% of Bt11 corn kernels as dry matter, did not develop any discernible clinical, hematological, biochemical, or ruminal abnormalities as compared with control calves (n=6) fed non-Bt11 corn. The results suggest that the transgenic Bt11 has no negative clinico-biochemical effects on calves.