Radial and between-family variations of the microfibril angle and the relationships with bending properties in Picea jezoensis families

With emphasis on tree breeding for wood quality in Picea jezoensis, we aimed to evaluate radial and between-family variations in the microfibril angle (MFA) of the S₂ layer in the latewood tracheids in 10 open-pollinated families of 43-year-old P. jezoensis trees. In addition, the relationships between MFA/wood density with the modulus of elasticity (MOE) or modulus of rupture (MOR) were investigated. Significant differences in MFA between families were found from the pith toward the bark. MFA showed higher values around the pith area, although some families showed relatively lower values than others around this area. In addition, due to a larger coefficient of variations of MFA near the pith, the potential for juvenile wood MFA improvement may be greater compared with mature wood. MOE was correlated with MFA in juvenile wood and with wood density in mature wood, whereas MOR was mainly correlated with wood density at radial positions in both woods. Therefore, to improve the MOE and MOR of P. jezoensis wood, both MFA and wood density would be factors to consider in both juvenile and mature woods. On the other hand, there are indications that, only wood density would be an important criterion for improving mature wood properties.     

Molecular identification of `Candidatus Mycoplasma haemovis' in sheep with hemolytic anemia

We examined the presence of hemoplasmas, hemotropic mycoplasmas, among 11 sheep (Ovis aries) with regenerative and hemolytic anemia and found six of them were positive by real-time PCR. The positive samples were then subjected to conventional PCR for direct sequencing of the 16S rRNA gene. Nucleotide sequences of all the positive samples were identified as the 16S rRNA gene of `Candidatus Mycoplasma haemovis' by phylogenetic analysis, demonstrating the infections with this particular hemoplasma species in Japan.     

Mechanical properties of wood in an unstable state due to temperature changes,and analysis of the relevant mechanism IV: effect of chemical components on destabilization of wood

In order to investigate the effects of chemical components and matrix structure on the destabilization of quenched wood, we examined the physical and mechanical properties of steam-treated wood, hemicellulose-extracted wood, and delignified wood, which were treated at different levels. For steam-treated and hemicellulose-extracted wood,the relative relaxation modulus of the quenched sample was lower than that of the respective control sample. For delignified wood, the relative relaxation modulus fell with weight loss and reached a minimum value at a certain weight loss, and subsequently increased significantly. The hygroscopicity of all treated samples changed slightly by steaming, whereas increased with removing the component. More-over, the average volumetric swelling per 1% MC at 100% relative humidity (RH) was less than at 75% RH and 93% RH for component-removed wood. It was clear that a void structure existed. As a result, the destabilization evaluated by the fluidity (1 - E _t/E ₀) of steam-treated wood was influenced by the amount of adsorbed water. For component-removed wood, destabilization increased temporarily at lower weight loss because of nonuniform cohesive structure. At high weight loss, destabilization will decreased because capillary-condensed water gathered in the voids and obstructed the motion of adsorbed water. However, the destabilization of all treated wood changed less than that of chemically modified wood.     

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.     

Interannual variability in stock abundance of the neon flying squid, Ommastrephes bartramii, in the North Pacific Ocean during 1979–1998: impact of driftnet fishing and oceanographic conditions

Variability in catch-per-unit-effort (CPUE) was examined for the autumn cohort of Ommastrephes bartramii collected with research driftnets during 1979–1998 along five longitudinal transects passing through the Subarctic, Transitional and Subtropical Domains in the North Pacific. CPUE was generally low during the period of intensive commercial driftnet fishing (1980–1992) and increased following the 1992 moratorium on the use of large-scale driftnets. However, CPUE levels were low for the cohorts hatched in 1992 and 1996 (captured in subsequent years owing to a one-year life of O. bartramii ) that experienced low sea surface temperatures from hatching to recruitment. Among similar-aged squid collected from 180° and 179°30'W in June, mantle lengths were significantly greater in 1997 than during 1995–96. These findings suggest that the driftnet fishery and sea surface temperatures from hatching to recruitment strongly affected stock abundance and possibly growth.     

A Recessive Lesion Mimic Mutant of Rice with Elevated Resistance to Fungal Pathogens

A gamma-ray-induced rice mutant, M1009, which spontaneously forms brown specks on leaves was isolated. In appearance, these lesions very much resemble those that are produced during the hypersensitive resistance response of rice to pathogens. A similar phenotype has been associated with a number of mutants in maize or Arabidopsis, which have been briefly categorized as disease lesion mimics. Brown speck formation was suppressed at temperatures of 25°C and above, and was severe at 20°C. Light irradiation is also required to initiate brown specks. In addition, the mutant exhibits heightened resistance to two major fungal pathogens of rice, Magnaporthe grisea and Cochliobolus miyabeanus. Genetic characterization of the mutant has indicated that its les-bs (lesion-brown speck) phenotype segregates as a monogenic recessive mutation. Received 13 September 1999/ Accepted in revised form 15 December 1999     

Relationship between zooplankton abundance and the early marine life history of juvenile chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis> in eastern Hokkaido,Japan

Interannual variations in abundance, timing of outmigration from rivers, growth rate and condition of juvenile chum salmon (Oncorhynchus keta) were studied in the Nemuro Strait (eastern Hokkaido, Japan) during 1999–2002 to establish a possible relationship to zooplankton abundance. The otolith microstructure of juveniles was examined each year in late June to determine their time and size at sea entry (i.e., outmigration), and to estimate the early marine growth rates. Salmon outmigration peaked in mid- or late May, which coincided, in three of the four study years, with the peak release of juveniles into rivers within the study area. Abundance, growth rate and condition of fish were higher in 2001, when—compared to other years—smaller fish experienced higher growth rates, coinciding with greater zooplankton abundance for that year. Our results suggest that high zooplankton abundance positively influenced juvenile chum salmon growth and the condition of the fish during their early marine life despite their small size at sea entry.     

Differentiation of canine bone marrow stromal cells into voltage- and glutamate-responsive neuron-like cells by basic fibroblast growth factor

We investigated the in vitro differentiation of canine bone marrow stromal cells (BMSCs) into voltage- and glutamate-responsive neuron-like cells. BMSCs were obtained from the bone marrow of healthy beagle dogs. Canine BMSCs were incubated with the basal medium for neurons containing recombinant human basic fibroblast growth factor (bFGF; 100 ng/ml). The viability of the bFGF-treated cells was assessed by a trypan blue exclusion assay, and the morphology was monitored. Real-time RT-PCR was performed to evaluate mRNA expression of neuronal, neural stem cell and glial markers. Western blotting and immunocytochemical analysis for the neuronal markers were performed to evaluate the protein expression and localization. The Ca²⁺ mobilization of the cells was evaluated using the Ca²⁺ indicator Fluo3 to monitor Ca²⁺ influx. To investigate the mechanism of bFGF-induced neuronal differentiation, the fibroblast growth factor receptor inhibitor, the phosphoinositide 3-kinase inhibitor or the Akt inhibitor was tested. The bFGF treatment resulted in the maintenance of the viability of canine BMSCs for 10 days, in the expression of neuronal marker mRNAs and proteins and in the manifestation of neuron-like morphology. Furthermore, in the bFGF-treated BMSCs, a high concentration of KCl and L-glutamate induced an increase in intracellular Ca²⁺ levels. Each inhibitor significantly attenuated the bFGF-induced increase in neuronal marker mRNA expression. These results suggest that bFGF contributes to the differentiation of canine BMSCs into voltage- and glutamate-responsive neuron-like cells and may lead to the development of new cell-based treatments for neuronal diseases.     

Fibrodysplasia ossificans progressiva-like condition in a cat

Fibrodysplasia ossificans progressiva (FOP)-like condition was diagnosed in a Japanese domestic cat with stiffness, marked atrophy of the muscles, and limited mobility of all joints in both the pelvic limbs. Etretinate, a retinoid, was used for medical management; however, no improvement in the clinical signs was observed. Inheritance of the disorder has not yet been demonstrated. Furthermore, the clinical signs and histopathological findings of feline FOP-like condition in the present case differed from those of the previously reported cases.