Histopathological and immunohistochemical features of proliferative lesions in the pituitary pars distalis of rats

Pituitary proliferative lesions derived from the endocrine cells of the pars distalis are frequently encountered and adenomas/carcinomas are a common cause of death in standard 2-year carcinogenicity studies using various rat strains, especially Sprague-Dawley. This report describes the immunohistochemical characteristics of pituitary tumors derived from the pars distalis in rats. Prolactin (PRL)-containing tumors are the most common, with PRL/growth hormone (GH) dual positive tumor masses (PRL/GH co-positive tumor masses) being more prevalent than only PRL-positive tumor masses (PRL single-positive tumor masses). GH-containing tumors are relatively numerous and many of these are also PRL/GH co-positive tumor masses. TSH-containing tumors are common in females. PRL-containing tumors have been shown to increase the incidence of hyperlactation in males and mammary adenomas/adenocarcinomas in females, suggesting that these masses are functional tumors.     

Isolation of an equine coronavirus from adult horses with pyrogenic and enteric disease and its antigenic and genomic characterization in comparison with the NC99 strain

A new equine coronavirus was isolated from the feces of adult horses with pyrogenic and enteric disease. The disease outbreak was mainly observed among 2- to 4-year-old horses living in stables of a draft-horse racetrack in Japan. On comparing the isolated virus (isolate Tokachi09) with the equine coronavirus NC99 strain, no significant differences were observed in several biological properties such as hemagglutinating activity, antigenicity (in indirect immunofluorescence and neutralization tests), and one-step growth (in cell culture). The sequences of the nucleocapsid and spike genes of isolate Tokachi09 showed identical size (1341 and 4092 nucleotides, 446 and 1363 amino acids, respectively) and high similarity (98.0% and 99.0% at the nucleotides, 97.3% and 99.0% at the amino acids, respectively) to those of strain NC99. However, the isolate had a 185-nucleotide deletion from four bases after the 3'-terminal end of the spike gene, resulting in the absence of the open reading frame predicted to encode a 4.7-kDa nonstructural protein in strain NC99. These results suggest that the 4.7-kDa nonstructural protein is not essential for viral replication, at least in cell culture, and that the Japanese strain probably originated from a different lineage to the North American strain. This is the first equine coronavirus to be isolated from adult horses with pyrogenic and enteric disease.     

Effect of the expression level of an AGAMOUS-like gene on the petaloidy of stamens in the double-flowered lily, ‘Elodie’

Double-flowered lilies, in which stamens are converted to petaloid organs, are valuable for horticulturists. ‘Elodie’ is a double-flowered lily cultivar in which stamens are homeotically converted into petaloid organs in whorl 3. The ‘Elodie’ cultivar shows individual variation in stamen structure and it was therefore classified into the following three types according to the strength of petaloidy of the stamens: weak (type-I), intermediate (type-II), and strong (type-III) phenotypes. The AGAMOUS (AG) gene is a class C floral identity gene in Arabidopsis thaliana that is involved in the formation of stamens and carpels. An AG-like gene was isolated from ‘Elodie’ (LelAG1) and its expression was compared between flower types. The LelAG1 gene was expressed in whorls 3 and 4, but not in whorls 1 and 2 in all flower types. In type-I flowers, LelAG1 was expressed strongly in whorls 3 and 4, while its expression was significantly decreased in whorl 3 in type-III flowers. In type-II intermediate phenotype flowers, the expression level of LelAG1 in whorl 3 was reduced by 60%. These results suggest that the expression level of AG-like genes is correlated with the degree of petaloidy of the stamens.     

Isolation of a Megatrypanum trypanosome from sika deer (Cervus nippon yesoensis) in Japan

A trypanosome was isolated from a sika deer (Cervus nippon yesoensis) in Hokkaido, Japan, during the primary culture of sika deer renal cells. This is the first report of isolation of a Megatrypanum trypanosome from Japanese Cervidae. The trypanosome, designated TSD1, was propagated and maintained in Eagle's modified essential medium containing 20% fetal bovine serum with sika deer renal cells as feeder. The TSD1 trypanosome was morphometrically similar to Trypanosoma cervi, which is commonly isolated from American and European deer. PCR analysis with primers for 18S ribosomal DNA and nucleotide sequencing showed that TSD1 is a member of genus Trypanosoma, subgenus Megatrypanum. Phylogenetically TSD1 is closely related to T. theileri, a common trypanosome of cattle, but is distinguishable from T. theileri by some morphometrical and biological features.     

Histological dermal changes caused by preparation and application procedures in percutaneous dose toxicity studies in dogs,rabbits and rats

We reevaluated histological slides of dorsal skin in control animals from past percutaneous dose toxicity studies using dogs, rabbits and rats to provide background data concerning histological changes related to preparation and application procedures and vehicles or embrocations of every variety. Acanthosis, dermal or perifollicular inflammatory cell infiltration in dogs; hyperkeratosis, acanthosis, dermal inflammatory cell infiltration or hemorrhage in rabbits; and acanthosis, dermal inflammatory cell infiltration, crust or foreign body granuloma in rats were present as procedure-related underlying histological changes in the control animals. Four mechanical acts, (1) rubbing with gauze to remove an administered substance for reapplication, (2) use of a taut bandage to avoid slipping from the application site, (3) peeling a patch off as a preparation procedure for reapplication, and (4) clipping or shaving, were considered to cause injury to the skin. The degree of influence of the various application procedures was found to be as follows: sham, lotion < cream < ointment and tape in dogs; untreated control, sham < lotion < tape and poultice in rabbits; and sham, sodium carboxymethylcellulose < olive oil and lotion < ointment and tape in rats. The degree of ointment influence on rabbits is equivocal.     

Plant Opal in Japanese soils

Several years ago the writers (6) found peculiar amorphous grains having a low refractive index (n = 1.45) in the tine sand fraction of Japanese volcanic-ash soils, especially in the A horizons of glassy-ash soils (Onji type). These grains have been considered PELE's tears (liquid lava drops) or bead-like glassy grains on the basis of their relative abundance in volcanic-ash soils. Their morphological, and chemical characteristics have been reported elsewhere by the authors (6). Furthermore, it has been noticed that many of red-yellow soils and paddy soils contain varying amounts of these grains. Some Japanese agronomists and phytopathologists have previously pointed out that silica cells in leaves of Oryza sativa have the effective power of resistance to blast (Imochi disease).     

Clay minerals of red-yellow soils derived from pleistocene sediments in Japan

Red-Yellow soils are widely developed on terraces and hilly lands in the south-western half of Japan. They do not show any evidence of bleaching in the lower part of the A horizon, and are characterized by an extremely strong acid reaction, and a very low base-status⁹⁾. There are few studies on clay mineralogy of Red-Yellow soils in Japan. Egawa et al⁴⁾. have reported on clay mineralogy of soils derived from the Pleistocene and the Tertiary sediments most of which may be regarded as Red-Yellow soils. Matsui and Katô¹⁰⁾ have described clay minerals of Red-Yellow soils derived from the Pleistocene sediment in the environs of Shinjobara, Shizuoka Prefecture. These investigations indicated that clay minerals of Red-Yellow soils derived from the Pleistocene sediments consisted mainly of kaolin minerals, whereas those of Red-Yell ow soils derived from the Tertiary sediments were of the kaolin-illite association.     

Glassy volcanic-ash soils in Japan

Introduction

In Tottori district, there can be seen an extensive sand-dune region, which develops on the coastal terrace of the volcanogenous diluvium running from east to west along the shore of the Japan Sea. There is about 9750 hectares in total area: 5265 hectares comprising numerous inter-dune depressions are used for tillage field, 1207 hectares afforested and 3278 hectares left barren.     

A scheme for soil classification of paddy fields in Japan with special reference to mineral paddy soils

Introduction

Paddy (irrigated) rice is the most important single crop in Japan. Nearly half of the total arable lands covering approximately 6.5 million hectares, are devoted to the growing of the rice plant. It is grown mainly on the alluvial plains which are intensively cultivated, and are the most productive soils of the country. Since the idea of modern pedology was introduced into Japan, some work has been done by some Japanese investigators to classify paddy soils on the basis of their morphological characteristics. A brief historical review on the soil survey work in Japan has been given by Kamoshita⁸⁾. In 1936 Kawamura described methods of soil survey in Korea through a careful study of the work developed by Stremme and his colleagues in Danzig. In those days Kamoshita⁹⁾,¹⁰⁾ devised a scheme of paddy soil classification by applying the concept of the wet soil types (mineralische Nassböden) proposed by Stremme, and he established five predominant soil types as follows: Bog soils (Moorböden), Half-bog soils (anmoorige Böden), Meadow soils (Wiesenböden), Gray lowland soils (graue Auenböden), and Brown lowland soils (braune Auenböden). The names in parentheses represent the wet soil types proposed by Stremme. These soil types are subdivided into soil kinds (Bodenarten) on the basis of differences in texture, rusty mottling, and humus content. The soil kinds were used as both categorical and cartographical units for detailed soil surveys.