Cyclosporine A inhibits the mRNA expressions of IL-2, IL-4 and IFN-gamma, but not TNF-alpha, in canine mononuclear cells

The effects of the calcineurin inhibitors cyclosporine A (CsA) and FK506 on the mRNA expressions of various cytokines were evaluated in dogs to determine whether the effects of CsA and FK506 in dogs were similar to those in humans. The mRNA expression levels of the cytokines IL-2, IL-4, IFN-gamma and TNF-alpha were measured in PHA-stimulated canine PBMC using real-time RT-PCR after incubation with CsA or FK506 for 5 hr. Both reagents inhibited IL-2, IL-4 and IFN-gamma mRNA expressions in a dose-dependent manner. However, CsA hardly inhibited the mRNA expression of TNF-alpha. These findings are important for assessing the indications of CsA treatment in dogs.     

Impact of land use on nitrogen concentration in groundwater and river water

Abstract

The aim of this study was to evaluate the impact of land use on nitrate nitrogen (NO₃-N) in shallow groundwater (G-N) and total nitrogen (N) in river water (R-N). The study area consisted of 26 watersheds (1342 km²) covering 72% of Kagawa Prefecture in Japan. We estimated G-N specific concentrations, which showed the magnitude of the upland fields, paddy fields, forests and urban land-use contributions to watershed-mean G-N. G-N specific concentrations were gained as partial regression coefficients using a multiple regression analysis of the watershed-mean G-N concentrations and the land-use ratios in each of the 26 watersheds. The results showed that the G-N specific concentration, which was gained as the partial regression coefficient for the multiple regression analysis, was 15.2 mg L^?1, 10.3 mg L^?1, 2.3 mg L^?1 and 2.5 mg L^?1 for the upland fields, paddy fields, forests and urban land-use types, respectively. R-N pollution load runoff to the river mouth was calculated by multiplying R-N specific concentration (previously reported) by river flow at the river mouth. Similarly, G-N pollution load arrival to groundwater was calculated by multiplying G-N specific concentration by the groundwater flow. The R-N pollution load runoff was 19.3 kg ha^?1 y^?1, 7.7 kg ha^?1 y^?1, 1.7 kg ha^?1 y^?1 and 7.6 kg ha^?1 y^?1, while the G-N pollution load arrival was 7.3 kg ha^?1 y^?1, 5.0 kg ha^?1 y^?1, 1.1 kg ha^?1 y^?1 and 1.2 kg ha^?1 y^?1, for upland fields, paddy fields, forests and urban areas, respectively. These results showed that the N in river water and groundwater was derived mainly from runoff and leaching from croplands. Therefore, the relationships between watershed-mean non-absorbed, applied nitrogen (NAA-N: nitrogen applied to cropland via fertilizer and manure without being absorbed by crops), R-N concentration and watershed-mean G-N concentration were investigated. A curvilinear correlation was observed between NAA-N and R-N concentrations (r² = 0.68) except for one small, high-density, urban watershed, and a weak linear correlation was observed between NAA-N and G-N concentrations (r² = 0.42).     

Characterization of ethylene biosynthesis and its regulation during fruit ripening in kiwifruit,Actinidia chinensis ‘Sanuki Gold’

Ethylene biosynthesis in kiwifruit, Actinidia chinensis ‘Sanuki Gold’ was characterized using propylene, an ethylene analog, and 1-methylcyclopropene (1-MCP), an inhibitor of ethylene perception. In fruit harvested between a young stage (66 days after pollination) (DAP) and an early commercial harvesting stage (143 DAP), 2 days of exposure to propylene were sufficient to initiate ethylene biosynthesis while in fruit harvested at commercial harvesting stage (154 DAP), 4 days of propylene treatment were required. This observation suggests that response of ethylene biosynthesis to propylene treatment in kiwifruit declined with fruit maturity. Propylene treatment resulted in up-regulated expression of AC-ACO1, AC-ACO2, AC-SAM1 and AC-SAM2, prior to the induction of AC-ACS1 and ethylene production, confirming that AC-ACS1 is the rate limiting step in ethylene biosynthesis in kiwifruit. Treatment of fruit with more than 5 μL L^?1 of 1-MCP after the induction of ethylene production subsequently suppressed ethylene production and expression of ethylene biosynthesis genes. Treatment of fruit with 1-MCP at harvest followed with propylene treatment delayed the induction of ethylene production and AC-ACS1 expression for 5 days. These observations suggest that in ripening kiwifruit, ethylene biosynthesis is regulated by positive feedback mechanism and that 1-MCP treatment at harvest effectively delays ethylene production by 5 days.     

Immunohistochemical analysis of pseudorabies virus spread through neurons innervating the eyeball

Pseudorabies virus (PRV) was inoculated intraocularly into BALB/c mice, and the distribution pattern of cells positive for several neurotransmitters and viral antigens in the eyeball, trigeminal nerve ganglia, and superior cervical ganglia was examined immunohistochemically to clarify the neural route of the virus spread. In the eyeball, substance P (SP)- and calcitonin gene-related peptide (CGRP)-positive cells were detected in the ipsilateral iris and ciliary body, neuropeptide tyrosine (NPY)-positive cells were detected in the choloid membrane, and tyrosine hydroxylase (TH)-positive cells were detected in the ipsilateral inner nuclear layer of the retina; all these cells contained viral antigens. In the superior cervical ganglia, viral antigen-positive cells containing TH or NPY were found at bilateral sites. In the trigeminal nerve ganglia, viral antigen-positive cells containing SP or CGRP were found at bilateral sites. These findings indicated that the SP- and CGRP-positive ganglion cells of the trigeminal nerve ganglia innervating the iris or ciliary body, and the NPY-positive ganglion cells of the superior cervical ganglia innervating the iris, ciliary body, and choroid membrane served as the route for the virus spread. These findings also suggested that dopaminergic neurons, such as the TH-positive retinal cells and TH-positive ganglion cells of the superior cervical ganglia, served as the route for virus spread.     

Susceptibility of Djungarian hamsters (Phodopus sungorus) to Neospora caninum infection

Djungarian hamsters were examined for the susceptibility to Neospora caninum infection. After 29 Djungarian hamsters were intraperitoneally inoculated with 5 x 10(6) N. caninum tachyzoites of JPA1 strain, some animals showed symptoms such as ataxia, and many tissue cysts were detected in the brain and a cyst in the muscular tunics of stomach. Especially, more than 100 cysts per head were observed after 5 weeks post inoculation. It is suggested that the Djungarian hamster is a model useful to examine neosporosis.     

Langerhans cells within the follicular epithelium and the intradermal sweat duct in equine insect hypersensitivity "Kasen"

Histopathologic and electron microscopic observations were given on Langerhans cells (LCs) within the follicular epithelium (FE) and intradermal sweat duct (ISD) of equine "Kasen". By light microscopy, LCs were present in the greatest numbers within the FE and ISD than within the epidermal layer and the normal skin, with an occasional formation of several aggregated foci. By electron microscopy, LCs within the FE and ISD widely extended their dendritic processes between the keratinocytes and contained Birbeck granules (Bgs), mitochondria, rough endoplasmic reticula and ribosomes in the cytoplasm. Numerous Type 2 LCs, with a number of Bgs and endocytosis, and Type 3 LCs, with multivesicular bodies and endosomes of various sizes, were recognized within the FE and ISD, although inactive Type 1 LCs, with a narrow and lucid cytoplasm, were rarely seen. LCs observed within the FE and ISD in the "Kasen" skin lesions might express the particular stage corresponded to recognize, intake and process the antigens which permeate them.     

Ultrastructural study of Langerhans cells in equine insect hypersensitivity "Kasen"

Ultrastructural features of Langerhans cells (LCs) of equine "Kasen" were studied. Electron microscopic observation revealed that LCs were dendritic and had irregular nuclear membranes. A number of Birbeck granules (Bgs) of various types were observed in the cytoplasm of LCs. In LCs in the upper stratum spinous, many Bgs were observed (Type 2 LC). LCs in the epidermo-dermal junction (EDJ) had a few Bgs, vesicles (multivesicular bodies) and highly electron-dense granular endosomes in the cytoplasm (Type 3 LC). Inactive LCs were also observed between the keratinocytes (Type 1 LC). Various types of LCs observed in the skin lesions of equine "Kasen" were interpreted as representing those that recognize, intake and process antigens.