Scanning electron microscopy of root resorption of feline teeth

Scanning electron microscopy was carried out on 10 feline extracted permanent teeth from 3 cases with root resorption. Various-sized resorption lacunae were well defined, showing an etched pattern and configuration as shown in human deciduous teeth. In cats, regardless of the shape and depth of lacunae, the resorption lacunae showed opening dentinal tubules in the wall with or without cement matrix apperring only in the deep and round lacunae of human cases. Some specific process of mineralization for repairing dental root resorption was suggested in cats.     

Nutrient dynamics in decomposing forest leaf litter: A comparison of field and laboratory microcosm approach

The effect of incubation setting (greenhouse: GM and field: FM microcosms) on nutrient element dynamics during decomposition of Japanese Konara Oak (Quercus serrata Murray) and Japanese Red Pine (Pinus densiflora Sieb et. Zucc.) litter was studied. Results show a disparity in relative concentrations and amounts of the same type of litter when incubated in different settings. The nutrient mobility, however, showed similar trend. The order of elemental mobility after 12 months forQuercus in FM was: P>K>Mg>C>Mn>Ca>N>Al>Cu>Zn>Fe; for GM it was: P>K>Mn>Mg>C>Ca>N>Al>Cu>Zn>Fe. ForPinus, elemental mobility in FM was: K>Mg>C>Mn>N>P>Cu>Zn>Al>Fe; while for GM was: K>C>Mn>N>Ca>Mg>Cu>Al>P>Zn>Fe. The elements inQuercus that lost their mass were P, K, Mg, Ca, Mn and C while those that increased were N, Cu, Al, Fe and Zn. ForPinus, K and Mg lost their nutrient mass while the other elements had increased or fluctuated but tended to increase. Three patterns of nutrient mobility were observed: first, the concentration increased while the nutrient mass (absolute amount) decreased; second, both concentration and nutrient mass increased; third, the concentration and nutrient mass decreased. On tracing nutrient mobility over time, the linear regression of nutrient element mass and litter element mass was preferred over the carbon to element ratios because the former gave a clearer picture of the relationship. On the over-all, the pattern of nutrient changes in greenhouse microcosms were different from those observed in the field, hence nutrient cycling studies using greenhouse-microcosm approach alone may give inaccurate results. This study was conducted while the senior author holds a Japanese government scholarship (MONBUSHO Grant No. 920205).     

Low pathogenicity H5N2 avian influenza outbreak in Japan during the 2005-2006

At the end of May 2005, a low-pathogenicity avian influenza (LPAI) virus of subtype H5N2 was isolated for the first time from chickens in Japan. Through active and epidemiological surveillance, 5.78 million chickens on 41 farms were found to be affected and 16 H5N2 viruses were isolated. Antigenic analysis revealed antigenic similarity of these isolates. Phylogenetic analysis showed that they originated from a common ancestor and clustered with the H5N2 strains prevalent in Central America that have been circulating since 1994. Experimental infection of chickens with the index isolate (A/chicken/Ibaraki/1/05) demonstrated that this virus replicated efficiently in the respiratory tract without clinical signs, and dust-borne and/or droplet-borne transmission was considered as a possible mode of transmission. These results suggested that the H5N2 LPAI viruses isolated in Japan were highly adapted to chickens.     

Effect of germanium,poly-trans-[2-carboxyethyl] germasesquioxane on natural killer (NK) activity in dogs

In an attempt to study the immunological effects on normal and adenocarcinoma (AC) dogs, the natural killer (NK) activity was determined. Augmentation of NK cell activities in responsive normal and AC dogs that indicatedanergy in the phaseolus vulgaris agglutinin (PHA) skin-test was manifested when the animals were accordingly treated with germanium (GN).     

Clinical significance of circulating vascular endothelial growth factor in dogs with mammary gland tumors

Increase in circulating vascular endothelial growth factor (VEGF) is suggested as a prognostic indicator in human patients with malignant tumors. The purpose of this study was to evaluate the clinical significance of circulating VEGF in dogs with mammary gland tumors (MGT). Both plasma and serum VEGF were significantly higher in dogs with MGT when compared with those in the healthy dogs. In dogs with MGT, the plasma and serum VEGF of the malignant group increased significantly compared with those of the benign group. Additionally, there was a significant difference between the plasma and serum VEGF in the groups with postoperative metastasis and no metastasis. Circulating VEGF is expected to be clinically available for the determination of prognosis in canine MGT.     

Assessment of left ventricular function using pulsed tissue Doppler imaging in healthy dogs and dogs with spontaneous mitral regurgitation

Pulsed tissue Doppler imaging (pulsed TDI) has been demonstrated to be useful for the estimation of left ventricular (LV) systolic and diastolic functions in various human cardiac diseases. The objectives of this study were to investigate the relationship between pulsed TDI and LV function by using cardiac catheterization in healthy dogs and to evaluate the clinical usefulness of pulsed TDI in dogs with spontaneous mitral regurgitation (MR). The peak early diastolic velocity (E'), peak atrial systolic velocity (A'), and peak systolic velocity (S') were detectable in the velocity profiles of the mitral annulus in all the dogs. In the healthy dogs, S' and E' were correlated with LV peak +dP/dt and -dP/dt, respectively. E' was lower in dogs with MR than in dogs without cardiac diseases. E/E' in the MR dogs with decompensated heart failure was significantly increased in comparison with those with compensated heart failure. The sensitivity and specificity of the E/E' cutoff value of 13.0 for identifying decompensated heart failure were 80% and 83%, respectively. In addition, E/E' was significantly correlated with the ratio of left atrial to aortic diameter. These findings suggest that canine pulsed TDI can be applied clinically for estimation of cardiac function and detection of cardiac decompensation and left atrial volume overload in dogs with MR.     

New virulent race of Phialophora gregata f. sp. adzukicola associated with continuous cultivation of adzuki bean cultivar Acc259

Adzuki bean cultivar Acc259, which is resistant to races 1 and 2 of Phialophora gregata f. sp. adzukicola, was used as a breeding resource for resistance to brown stem rot (BSR). During the third year after two successive cultivations of Acc259, a severe outbreak of BSR occurred in an experimental plot at the Tokachi Agricultural Experiment Station, Hokkaido, Japan. The isolates obtained from diseased plants were virulent to Erimo-shozu (susceptible to all races) and Acc259 but avirulent to Kita-no-otome (resistant to race 1 but susceptible to race 2). The existence of a new race of P. gregata f. sp. adzukicola, designated race 3, was determined; and its frequency in the plot soil was shown to increase from 16.7% before planting Acc259 to 100% after the third year. Of 140 isolates from the commercial production area that were formerly identified as race 1, 13 were actually race 3 and were restricted to certain limited fields.     

Distribution of the androgen receptor in the diencephalon and the pituitary gland in goats: Co-localisation with corticotrophin releasing hormone, arginine vasopressin and corticotrophs

Previously it has been shown that androgen suppresses transportation-induced increases in plasma adrenocorticotropic hormone (ACTH), possibly by suppressing the secretion of corticotrophin releasing hormone (CRH) or arginine vasopressin (AVP) from the hypothalamus, or secretion of ACTH from the pituitary gland. The aim of the present study was to examine androgen target sites in the caprine diencephalon and pituitary gland using immunohistochemical methods. The androgen receptor (AR) was expressed strongly in the bed nucleus of the stria terminalis, the medial preoptic area, the arcuate nucleus, the ventromedial hypothalamic nucleus and the suprachiasmatic nucleus in the diencephalon. Between 8% and 11% of CRH and AVP neurons in the paraventricular hypothalamic nucleus (PVN) expressed AR. In the pituitary gland, 7.1% of corticotrophs expressed AR. The results are consistent with the proposal that androgen acts directly and indirectly on CRH and/or AVP neurons in the PVN. The possibility of a direct action of androgen on the corticotrophs in the pituitary gland was also considered.     

Successful treatment by percutaneous transvenous coil embolization in a small-breed dog with intrahepatic portosystemic shunt

A Miniature Dachshund, 3-month-old, 3.1 kg, was diagnosed as an intrahepatic portosystemic shunt (PSS) with the shunting vessel in 6-mm diameter. Percutaneous transvenous coil embolization (PTCE) was performed with a stainless steel coil in 8-mm diameter. Intraoperative portal pressure elevated about 2.5 times after one-stage coil occlusion. Two weeks after the PTCE, serum bile acid levels reduced within the normal range. The portogram showed complete occlusion of the shunting vessel 4 months after the PTCE. Approximately 3 years after the PTCE, the patient has shown no clinical signs. PTCE could be performed more easily and less invasively in a small-breed dog. It is therefore suggested that PTCE is a promising therapeutic technique in canine intrahepatic PSS.