Effect of setting conditions on mechanical properties of acid-induced Kamaboko gel from squid <Emphasis Type="Italic">Todarodes pacificus</Emphasis> mantle muscle meat

Squid Todarodes pacificus suwari gels, set at various temperatures and times, and acid-induced kamaboko gel, which was prepared by soaking suwari gel in 5% acetic acid for 20 h, were studied to evaluate the mechanical properties that are affected by setting conditions. Unset squid meat paste did not form a gel when soaked in acetic acid. The breaking strength of both suwari gel and acid-induced kamaboko gel showed a tendency to increase with setting temperature and time. SDS-PAGE analysis of suwari gel and acid-induced kamaboko gel, which were set at various temperatures and times, showed that myosin heavy chain (MHC) was observed at 30°C only for the first hour. The intensity of the MHC band at 30°C gradually decreased with setting time, while the intensity of the polymer band gradually increased with setting time. These results suggest that the protein-protein bonds in suwari gel affect the final texture of acid-induced kamaboko gel. Based on the analysis of the mechanical properties, and in consideration of the fact that the purpose of this experiment was to reduce energy usage, the best setting condition was determined to be 40°C for 3 h.     

A piglet with concurrent polioencephalomyelitis due to porcine teschovirus and postweaning multisystemic wasting syndrome

A piglet developed respiratory distress followed by difficulty in standing and unsteady gait. The lesions were characterized by polioencephalomyelitis with the predominant distribution in the brain stem, as well as lymphocyte depletion and histiocyte infiltration with cytoplasmic inclusion bodies in the lymphoid tissues throughout the body and interstitial pneumonia. Porcine teschovirus (PTV) antigens were found in the former lesions and porcine circovirus 2 (PCV2) in the latter two lesions. PTV genes were detected from the diencephalon. The results suggest that the piglet was concurrently affected with polioencephalomyelitis due to PTV and postweaning multisystemic wasting syndrome (PMWS) associated with PCV2. They also suggest that the immunosuppressive condition developing in PMWS may have facilitated the infection of the brain with PTV.     

Relationship between retinoic acid receptor alpha gene expression and growth-inhibitory effect of all-trans retinoic acid on canine tumor cells

Retinoids show antitumor effects on human acute promyelocytic leukemia and other tumors via retinoid receptors. In dogs, the role of retinoid receptors in inhibiting tumor development remains unclear. To evaluate the correlation between the degree of expression of retinoic acid receptor alpha (RARalpha) mRNA and the antiproliferative effects of all-trans retinoic acid (ATRA) treatments, expression analysis of RARalpha mRNA and cell growth inhibition assay were performed on 17 established canine tumor cell lines, including 6 mammary gland tumor (MGT) cell lines, 3 osteosarcoma cell lines, 5 melanoma cell lines, and 3 mast cell tumor (MCT) cell lines. Among the cell lines investigated, all 3 MCT cell lines showed high expression of RARalpha, and the most effective cell growth inhibition was observed in ATRA-treated MCT cell lines. However, remarkable antiproliferative effects of ATRA treatments were not observed on other tumor cell lines with moderate or low RARalpha mRNA expression. As a result of the relationship between RARalpha mRNA expression and ATRA treatment with regression analysis, statistically significant correlation was suggested. Furthermore, real-time quantitative polymerase chain reaction analysis of RARalpha was performed on MCT tissue samples of dogs with spontaneous disease, and 5 of 9 tissues showed high expression. These results suggest that ATRA may be an effective antitumor agent for MCT in dogs, and that prior measurement of expression of RARalpha mRNA may be a good indicator of the effectiveness of ATRA treatment.     

Effects of dietary Nannochloropsis sp. powder and lipids on the growth performance and fatty acid composition of larval and postlarval kuruma shrimp,Marsupenaeus japonicus

The current study evaluated the effects of fish oil replacement with eicosapentaenoic acid‐enriched single‐cell microalgae in the diets of larval and postlarval kuruma shrimp. Experimental diets containing different level of Nannochloropsis sp. powder (10, 40, 70 g/kg) and lipids (2, 8, 10, 14, 35, 58 g/kg) were evaluated. The substitution of fish oil with algal powder significantly improved shrimp growth compared to that in the control group, with the highest final body weight recorded at 70 g/kg in larvae and 40 g/kg in postlarvae. Larvae fed algal lipids with a dry weight percentage in the diet of greater than 10 g/kg showed significantly lower performance than those in the control group. The neutral lipids in the tissue of the postlarvae that had been fed algal lipids had an improved fatty acid profile, as the content of highly unsaturated fatty acids increased compared to that in the other groups. The content of docosahexaenoic acid increased in the tissue, indicating the possible occurrence of the metabolism and accumulation of Nannochloropsis sp. essential fatty acids. Algal powder could replace FO up to 140 g/kg in shrimp diets without compromising growth and FA profiles.     

Induction of centrum defects in amberjack Seriola dumerili by exposure of embryos to hypoxia

ABSTRACT:   Artificially hatched Seriola species have the problem of malformation, mainly in their vertebrae, head, and mouth parts. To clarify the cause of vertebral malformation, the effects of hypoxia during embryogenesis on the induction of centrum defects was investigated in artificially hatched amberjack Seriola dumerili . Firstly, 7-somite stage embryos were exposed to waters of 0, 12.5, 25, 50, and 100% dissolved oxygen (DO) for 0.5, 1, 2, 3, 4, and 5 h to confirm the effective dose (DO concentration and duration of exposure) of hypoxia that induces somitic disturbances in newly hatched larvae. Exposure of embryos to 12.5% DO concentration for longer than 0.5 h induced somitic disturbances. Following this result, centrum defects in juveniles were investigated by an induction experiment with embryos exposed to 12.5% DO for 2 h at the gastrula, 1- or 2-somite, 10-somite, 15-somite, or heart beating stage. This experiment revealed that centrum defects were induced only during somitogenesis, and somitic disturbances were the premonitory symptom of centrum defects. These results indicate hypoxia during somitogenesis as a possible cause of centrum defects in amberjack.     

Combined ataxia telangiectasia mutated and DNA-dependent protein kinase inhibition radiosensitizes Madin–Darby canine kidney cells

Uncovering radiation toxicity is critical for the adaptation and expansion of advanced radiation therapies and for the development of novel cancer radiotherapy. In the near future, advanced radiotherapies, including heavy ion beam treatment, are expected to be applied in the treatment of dogs, but further basic research on the effects of radiation using canine normal and cancer cells is necessary to actually apply these techniques and achieve high therapeutic efficacy. The radiation sensitivity is varied by the activities of DNA damage response (DDR) and DNA repair. The development of radiosensitizers that target DDR- and DNA repair-kinases, like ataxia telangiectasia mutated (ATM) and DNA-dependent protein kinase (DNA-PK), is progressing and is expected to be introduced into canine radiotherapy. However, there are no cytotoxicity reports on using the combination of radiation and these sensitizers as treatment in canine cells. In this study, we examined the cytotoxic effects of X-rays and/or radiosensitizers on the Madin–Darby canine kidney (MDCK) cell line. Our results show that X-rays suppress MDCK cell colony formation and proliferation in a dose-dependent manner. Additionally, our observations imply that the combination treatment with ATM inhibitor KU-55933 and DNA-PK inhibitor NU7441 significantly increased X-ray cytotoxicity in MDCK cells compared with the drugs alone. Furthermore, our findings further suggest that MDCK cells might be useful in clarifying the cytotoxicity in canine epithelial cells due to radiation and/or radiosensitizers, such as molecule-targeted drugs.     

Effects of dopamine, dobutamine, amrinone and milrinone on regional blood flow in isoflurane anesthetized dogs

The effects of cyclic AMP increasing cardiotonics (dopamine, dobutamine, amrinone and milrinone) on the blood flow in most organs were compared using colored microsphere technique in isoflurane-anesthetized dogs. Dopamine increased blood flow in ventricular myocardium. Furthermore dopamine induced the increase in blood flow in intestine and kidney at low to middle dose, but not at high dose. Dobutamine induced the highest increase in blood flow in ventricular myocardium and skeletal muscle among the drugs evaluated at middle and high doses. Amrinone and milrinone increased blood flow in ventricular myocardium almost same with catecholamines, and milrinone decreased vascular resistance moderately in most other organs. Milrinone might be more useful than catecholamines for improvement of congestive heart failure or peripheral circulatory failure accompanied with exceeded vasoconstriction.     

Secondary erythrocytosis associated with schwannoma in a dog

An 11-year-old, spayed female mixed-breed dog showed clinical signs of right forelimb lameness and pain by palpation around the neck. Radiography and computed tomography (CT) revealed an extradural mass at the 6th and 7th cervical vertebrae, which compressed the spinal cord. The mass was surgically removed and histopathologically diagnosed as schwannoma. The dog recovered her normal gait after hemilaminectomy and removal of the mass. Ten months after the surgery, the tumor recurred with absolute erythrocytosis and was surgically removed again. This removal temporarily resolved the erythrocytosis with a decrease in plasma erythropoietin (EPO) concentration. EPO protein was detected immunohistochemically in the tumor cells. Erythrocytosis in this dog may be caused by ectopic EPO produced in the schwannoma tissues.     

Effects of antimicrobial peptides derived from the beetle Allomyrina dichotoma defensin on mouse peritoneal macrophages stimulated with lipopolysaccharide

We previously reported that synthetic peptides, RLYLRIGRR-NH2 (peptide A) and RLRLRIGRR-NH2 (peptide B), derived from the beetle Allomyrina dichotoma defensin, showed antimicrobial activity against both Gram-positive and negative bacteria and suppressed lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF-alpha) mRNA expression in a murine macrophage cell line. In this study, inhibitory effects of these peptides in LPS-induced mouse peritoneal macrophage activation were investigated. The supplement of peptide A to macrophages cultured with LPS resulted in a significant decrease in nitric oxide and TNF-alpha production. Furthermore, NF-kappaB activation was also blocked by addition of peptide A. These results indicated that peptide A blocked macrophage activation induced by LPS.     

Molecular cloning of canine mucosal addressin cell adhesion molecule-1 cDNA and its expression in normal tissues

A cDNA encoding canine mucosal addressin cell adhesion molecule-1 (MAdCAM-1) was cloned. The entire open reading frame of canine MAdCAM-1 cDNA comprises 1137 bp, corresponding to 378 amino acid residues. The deduced amino acid sequence of canine MAdCAM-1 was 55.2%, 53.7%, and 52.4% identical to rat, mouse, and human MAdCAM-1, respectively. Canine MAdCAM-1 appeared to contain two immunoglobulin-like domains at the N-terminus, followed by a mucin-like domain and a third immunoglobulin-like domain. The structures of the dog, rat, and mouse proteins are likely similar because all of the cysteine residues in the immunoglobulin-like domains were conserved. Canine MAdCAM-1 mRNA was confirmed to express extremely in the mesenteric lymph node by RT-PCR.