Changes in collagen fiber content and hepatic stellate cell distribution in the liver of chick embryos and growing chickens

The content of collagen and the distribution of hepatic stellate cells (HSCs) were studied to elucidate the occurrence of sex‐dependent variations in the liver of developing embryos and growing chickens. Chick embryos from embryonic days (e) 12 to e20 and chicks at 1, 4 and 8 weeks were analyzed. Liver tissue was processed using NaOH maceration and freeze‐dried to obtain the collagen fiber specimens. HSCs were identified by double fluorescent immunohistochemistry for desmin and vimentin. There were no sex‐dependent variations in the percentage of collagen fiber per liver weight and HSC area during embryonic stages. However, the content of collagen fiber increased during embryonic development in both sexes. On the other hand, the area of HSCs significantly increased in growing males but did not show any change in females. Importantly, sex differences were observed in both collagen fiber content and HSC area in the liver at 8 weeks. These results indicate that the occurrence of collagen content variations takes place at 8 weeks in chicken liver, suggesting that a sex‐dependent hormone may play an important role on the collagen production of HSCs in the growing chicken liver.     

Invasion and colonization of mature apple fruit by Erwinia amylovora tagged with bioluminescence genes

Invasion and colonization of mature apple fruit by a transformant of Erwinia amylovora tagged with bioluminescence genes from Vibrio fischeri was examined. The transformant was deposited on cut surfaces of fruit stems, wounds on the shoulders and calyces, injured fruit-bearing twigs of harvested apple fruit, and cut fruit flesh. After incubation in closed stainless steel or plastic boxes at 25°C, fruit were periodically observed with a two-dimensional luminometer. The presence of the transformant in luminous areas was confirmed by isolating it on selective media. E. amylovora, when deposited in fruit stems: (1) can invade mature as well as immature apple fruit; (2) vertically and horizontally spreads and colonizes along vascular bundles, increasing its population; (3) reaches the calyx end and the flesh just under the exocarp within 3–4 days after inoculation; (4) when deposited on cut fruit flesh, irrespective of its maturity, can easily increase its population and survive 2–4 weeks or more at 25°C; and (5) even at the time of fruit maturation, can migrate within twigs rapidly and reaches the abscission layers between fruit-bearing twigs and fruit stems.     

Determination of antigenic proteins of housedust mites in 90 dogs suffering from atopic dermatitis

Housedust mites, Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae), are the important causative agents of allergic diseases in human and animals. By using 165 dogs suffering from atopic dermatitis (AD), serum levels of immunogloblin E (IgE) antibody against 25 kinds of allergen including housedust mites were determined. Housedust mites were the most frequent allergen against which 90 of the 165 allergic dogs (54.5%) by IMMUNODOT assay. With the further analysis of immunoblotting assay in the 90 dogs sensitized with housedust mites, antigenic proteins of housedust mites recognized by IgE antibodies were with the apparent molecular masses of 15, 76, 90, 98, and 170-kD. Among them, the 15-kD protein that might be identical to Group 2 antigens (Der f2, Der p2) was prominently observed (52/90). This study indicates that about a half of dogs with AD were sensitized to housedust mites, suggesting that Group 2 antigens of housedust mites may be a major allergen in canine AD.     

Modeling the spatially dynamic distribution of humans in the Oregon (USA) Coast Range

A common approach to land use change analyses in multidisciplinary landscape-level studies is to delineate discrete forest and non-forest or urban and non-urban land use categories to serve as inputs into sets of integrated sub-models describing socioeconomic and ecological processes. Such discrete land use categories, however, may be inappropriate when the socioeconomic and ecological processes under study are sensitive to a range of human habitation. In this paper, we characterize the spatial dynamic distribution of humans throughout the forest landscape of western Oregon (USA). We develop an empirical model describing the spatial distribution and rate of change in historic building densities as a function of a gravity index of development pressure, existing building densities, slope, elevation, and existing land use zoning. We use the empirical model to project changes in building densities that are applied to a 1995 base map of building density to describe future spatial distributions of buildings over time. The projected building density maps serve as inputs into a multidisciplinary landscape-level analysis of socioeconomic and ecological processes in Oregon's Coast Range Mountains. This revised version was published online in July 2006 with corrections to the Cover Date.     

Serological Differences among Erwinia amylovora Biovars

Serological properties were compared among four biovars of Erwinia amylovora. Two biovars (bvs. 1 and 2) from Maloideae sources outside of Japan, one (bv. 3) from Rubus idaeus and one causing bacterial shoot blight of pear (bv. 4) had different reactions in Ouchterlony double diffusion tests using living cells and lipopolysaccharides (LPS) as antigens. These findings indicate that E. amylovora can be classified into three serotypes; i.e., bvs. 1 and 2, bv. 3 and bv. 4. From results of Ouchterlony double diffusion tests and immunoblots, the specific antigen of the three serotypes may each exist in the LPS of E. amylovora strains. Received 27 March 2002/ Accepted in revised form 2 July 2002     

Th2 immune responses and alternatively activated macrophages (AAMacs) in helminth infection in aged mice

This study aims to understand Th2 immune responses and alternative macrophage activation against nematode parasites in aged mice. Eighteen-month (18 M) and three-month (3 M) old C3H/HeN mice were inoculated with Heligmosomoides polygyrus (Hp) larvae. Real-time PCR analysis indicated that interleukin (IL)-4 and IL-13 gene expression was elevated in both groups after infection, but the expression level was significantly low in 18 M mice. Macrophage phenotype was monitored by measuring arginase-1 gene expression and immunofluorescence staining in small intestine, showing a decrease in the number of alternatively activated macrophages (AAMacs) around worm cysts in 18 M mice. These results suggest that the Th2 immune response in aged mice against a nematode parasite was not sufficiently induced to promote AAMacs.     

Effects of oral glucosamine hydrochloride administration on plasma free amino acid concentrations in dogs

We examined the effects of oral glucosamine hydrochloride (GlcN), N-acetyl-D-glucosamine (GlcNAc) and d-glucose (Glc) administration on plasma total free amino acid (PFAA) concentrations in dogs. The PFAA concentrations increased in the control group and the GlcNAc group at one hour after feeding, and each amino acid concentration increased. On the other hand, in the GlcN group and the Glc group PFAA concentrations decreased at one hour after feeding. A significant decrease in amino acid concentration was observed for glutamate, glycine and alanine. Our results suggest the existence of differences in PFAA dynamics after oral administration of GlcN and GlcNAc in dogs.     

Leak-preventing effect of synthetic soil conditioners in paddy field

Synthetic soil conditioners have been studied by many soil scientists, but their studies were mainly on the formation of the water-stable aggregate of soils. But it may be possible that, if synthetic soil conditioners, the water-soluble polymers, are spread on the plowsole of the leaky paddy field, the leakage of water is prevented by the thin layer of the polymer formed by the swelling with irrigation water.