Isolation of genes showing increased expression during bovine adipocyte differentiation

The adipocyte is important not only for the storage of excess energy as fat, but also for the secretion of homeostatic factors. Gene expression profiles during adipocyte differentiation have been reported previously for mouse 3T3‐L1 cells. However, the profiles of adipogenic gene expression in mice and cattle may be different because several metabolic pathways of the ruminant adipose tissue are different from those of non‐ruminants. The gene expression profile in a clonal bovine intramuscular preadipocyte cell line during adipogenesis was examined using the polymerase chain reaction‐subtraction method. Six hundred and twenty‐one clones, which were expressed at an early stage of differentiation, from the preadipocyte to adipocyte, were isolated and characterized. Further detailed studies were carried out for 86 selected genes using northern blotting. Ten genes were found to be highly expressed after differentiation of bovine intramuscular preadipocyte cells. In particular, the expression profiles of genes for stearoyl CoA desaturase and FK506 binding protein were quite different from the time course of differentiation of that seen in the 3T3‐L1 cells reported previously. In addition, these genes were assigned to bovine chromosomes using a bovine/hamster somatic cell hybrid panel and public database.     

Olfactory neuroepithelioma in a dog: an immunohistochemical and electron microscopic study

A case of olfactory neuroepithelioma was investigated electron microscopically and immunohistochemically. The tumor mass was found in the nasal cavities of a 10-year-old female dog, which showed epistaxis, nasal discharge and facial swelling. The tumor tissue consisted of tubular structure of cuboidal to columnar cells and compactly arranged nests of small cells surrounded by a fibrovascular stroma. Mitotic figures were frequently observed. Immunohistochemically, the tumor cells frequently showed positive for neurofilament protein, synaptophysin and/or carnosine in addition to keratin. Ultrastructurally, tight junction was observed between the tumor cells. No dense-cored secretory granules were shown in the tumor cells. These findings indicated that the present tumor had neuronal and epithelial features probably originating from the olfactory epithelium.     

Mediastinal lymphoma with complete atrioventricular block in a horse

A 15-year-old, neutered-male pony presented with a history of weight loss during 4 months. Clinical evaluation revealed severe bradycardia and complete atrioventricular block. At necropsy, a lobulated mass in the anterior mediastinum and moderate enlargement of the superficial cervical lymph nodes were observed. The vagus nerve and the brachiocephalic trunk were embedded in this anterior mediastinal tumor. Histologically, the mass was composed of sheets of neoplastic lymphoid cells expressing CD3, with a low mitotic rate. To the best of our knowledge, this is the first reported case of mediastinal lymphoma associated with complete atrioventricular block in horses.     

Quantitative structure–activity studies of optically active 2-methoxy-1,3,2-oxazaphospholidine 2-sulfides against Musca domestica L

The quantitative relationship between the structure of optically active 4-substituted 2-methoxy-1,3,2-oxazaphospholidine 2-sulfides (4-RMOS) and their insecticidal activity on the house fly, Musca domestica L., was analysed using reported physicochemical parameters and regression analysis. The configuration at the C₄ atom was more important for insecticidal activity than that at the phosphorus atom, since the coefficient of the dummy parameter for the C₄- configuration was larger than that for the configuration of the phosphorus atom: (S)c(R)p diastereoisomers showed the highest insecticidal activity, and the activity decreased in the order of (S)c(R)p > (S)c(S)p > (R)c(R)p > (R)c(S)p. The electronic nature of the substituent at the C₄ position was the most important, followed by the steric and hydrophobic effects: the more electron-donating, the less bulky and the more hydrophobic the 4-substituent, the higher the insecticidal activity. Thus the highest activity was obtained for the isopropyl derivatives, and the activity decreased in the order of isopropyl > isobutyl > ethyl > sec-butyl > benzyl > phenyl > methyl > tert-butyl.     

Multiple osseous metastases of a carotid body tumor in a dog

Metastasis of malignant carotid body tumor to multiple bones was detected in a 13-year-old female Siberian husky dog. Radiographs exhibited an abnormal mass in the retropharyngeal site and osteolytic lesions in the vertebral bodies, spinous process, tibia, and ribs. At necropsy, multiple masses were observed in the bones as well as at the dorsal area of the retropharynx. Histologically, the tumor cells, arranged in sheets and clusters, had eosinophilic finely granular cytoplasm. Immunohistochemistry showed the tumor cells were positive for neuron-specific enolase and synaptophysin. Electron microscopy demonstrated a number of dense membrane-bound granules in the cytoplasm of the tumor cells. Based on these findings, this case was diagnosed as multiple bone metastases of a malignant carotid body tumor. Spinal cord damage induced by the tumor mass was the cause of the hind limb paralysis of the present dog.     

Cryoprotective effects of shrimp head protein hydrolysate on gel forming ability and protein denaturation of lizardfish surimi during frozen storage

ABSTRACT:   The effects of shrimp head protein hydrolysate (SHPH) from three species of shrimp (northern pink shrimp [ Pandalus eous ], endeavour shrimp [ Metapenaeus endeavouri ], black tiger shrimp [ Penaeus monodon ]) on gel forming ability and protein denaturation of lizardfish surimi during frozen storage at −25°C were evaluated. The quality of lizardfish surimi with 5% (dried matter) of any of the three SHPH or sodium glutamate (Na-Glu) was examined in terms of gel strength, whiteness, Ca-ATPase activity and the amount of unfrozen water, comparing with those of surimi without additive as the control. The residual Ca-ATPase activity and gel strength of surimi with SHPH were higher than those of the control throughout 180 days of frozen storage, regardless of shrimp species. The highest effect was found in surimi with Na-Glu. The gel strength and Ca-ATPase activity found a high positive correlation. The addition of SHPH to surimi also increased the amount of unfrozen water by approximately 1.29–1.36 fold higher than the control, however kamaboko gels of the control was significantly whiter. From these results, freeze-induced denaturation of lizardfish muscle protein could be lessened by the addition of SHPH, resulting in a high gel strength and Ca-ATPase activity.