Effect of Pueraria mirifica on the sexual skin coloration of aged menopausal cynomolgus monkeys

To investigate the estrogenic effect of Pueraria mirifica (PM), a Thai herbal plant that contains many phytoestrogens, sexual skin coloration was studied in cynomolgus monkeys. Aged menopausal monkeys were divided into three groups. Each group (n=3) was fed 10, 100, or 1,000 mg of PM daily. The treatment schedule was divided into three periods, a 30-day pre-treatment period, 90-day treatment period, and 60-day post-treatment period. The results show that the sexual skin exhibited reddish coloration within 24 h after PM-treatment and remained this way for the first half of the PM-feeding period. The changes in sexual skin coloration were not dose-dependent. The present results indicate that PM had estrogenic action by increasing reddish sexual skin coloration in aged menopausal monkeys.     

The muscle protein Dok-7 is essential for neuromuscular synaptogenesis

The formation of the neuromuscular synapse requires muscle-specific receptor kinase (MuSK) to orchestrate postsynaptic differentiation, including the clustering of receptors for the neurotransmitter acetylcholine. Upon innervation, neural agrin activates MuSK to establish the postsynaptic apparatus, although agrin-independent formation of neuromuscular synapses can also occur experimentally in the absence of neurotransmission. Dok-7, a MuSK-interacting cytoplasmic protein, is essential for MuSK activation in cultured myotubes; in particular, the Dok-7 phosphotyrosine-binding domain and its target in MuSK are indispensable. Mice lacking Dok-7 formed neither acetylcholine receptor clusters nor neuromuscular synapses. Thus, Dok-7 is essential for neuromuscular synaptogenesis through its interaction with MuSK.     

Identification of a novel locus Rmo2 conditioning resistance in barley to host-specific subgroups of Magnaporthe oryzae

Barley cultivars show various patterns of resistance against isolates of Magnaporthe oryzae and M. grisea. Genetic mechanisms of the resistance of five representative barley cultivars were examined using a highly susceptible barley cultivar, 'Nigrate', as a common parent of genetic crosses. The resistance of the five cultivars against Setaria, Oryza, Eleusine, and Triticum isolates of M. oryzae was all attributed to a single locus, designated as Rmo2. Nevertheless, the Rmo2 locus in each cultivar was effective against a different range of isolates. Genetic analyses of pathogenicity suggested that each cultivar carries an allele at the Rmo2 locus that recognizes a different range of avirulence genes. One allele, Rmo2.a, corresponded to PWT1, which conditioned the avirulence of Setaria and Oryza isolates on wheat, in a gene-for-gene manner. The other alleles, Rmo2.b, Rmo2.c, and Rmo2.d, corresponded to more than one avirulence gene. On the other hand, the resistance of those cultivars to another species, M. grisea, was conditioned by another locus, designated as Rmo3. These results suggest that Rmo2 is effective against a broad range of blast isolates but is specific to M. oryzae. Molecular mapping revealed that Rmo2 is located on the 7H chromosome.     

Persistence of inclusions and antigens of chicken anemia virus in Marek's disease lymphoma

The pathogenesis of the co-infection of CAV to MDV is complicated. In order to investigate the impact of CAV on the transformation phase of MD, MDV and, subsequently, CAV, were inoculated at 1day and 4weeks of age, respectively. Chickens were divided into six groups; vvMDV, vvMDV-CAV, vMDV, vMDV-CAV, CAV and a control group. The CAV inclusions and antigens were continuously detected in MD lymphomas in the vMDV-CAV and vvMDV-CAV groups in large bizarre-shape (presumably CD4(+) T cells) and small MD lymphoid cells (presumably CD8(+) T cells). The MD lymphomas were composed primarily of CD4(+) T cells, but CD8(+) T cells were infiltrated singly or in clusters. CAV enhanced the MDV-induced brain lesions in the vMDV-CAV group. The lymphoproliferative lesion (LP) in the vvMDV-CAV and vMDV-CAV groups was non-significantly higher than those in vvMDV and vMDV groups, respectively. CAV significantly increased the LP lesion in sciatic nerves. In conclusion, MD lymphomas enabled CAV replication and dissemination. The depletion of CTLs by CAV did not significantly affect progression of MD lymphoma, although they are essential for possible transition of lymphomatous to inflammatory lesion.     

Estimation of glomerular filtration rate in calves using the contrast medium iodixanol

To develop a simple procedure for estimating glomerular filtration rate (GFR) in calves, a three-sample method using iodixanol was first compared to that using the standard agent inulin. Iodixanol and inulin were co-administered intravenously to calves at 40 mg I/kg and 40 mg/kg, respectively, and blood was collected 30, 60, 120, and 180 min later. Serum iodixanol and inulin concentrations were separately determined by high performance liquid chromatography and colorimetry. Serum urea nitrogen (UN) and creatinine concentrations were also measured. GFR estimated by iodixanol was consistent with that using inulin in clinically healthy calves. Based on GFR estimations in healthy calves and those renal-loaded with iodixanol, it was found that the serum creatinine concentrations became elevated when GFR decreased to 60% of the reference value. In contrast, serum UN concentrations fluctuated widely, presumably due to extra-renal factors. When GFR was estimated using the three-sample method and compared with the single-blood-sample method, 62/69 (90%) of samples tested were within the agreement plots. The results demonstrated that the single-blood-sample method using iodixanol may be useful in monitoring GFR in calves.     

Vertical soil–air CO2 dynamics at the Takayama deciduous broadleaved forest AsiaFlux site

At the Takayama deciduous broadleaved forest Asiaflux site in Japan, the ecosystem carbon dynamics have been studied for more than two decades. In 2005, we installed non-dispersive infrared CO₂ sensors in the soil below the site’s flux tower to systematically study vertical soil–air CO₂ dynamics and explain the behavior of soil surface CO₂ efflux. Soil–air CO₂ concentrations measured from June 2005 through May 2006 showed sinusoidal variation, with maxima in July and minima in winter, similar to the soil CO₂ effluxes measured simultaneously using open-flow chambers. Soil–air CO₂ concentrations increased with soil depth from 5 to 50 cm: from 2,000 to 8,000 ppm in the summer and from 2,000 to 3,000 ppm in the winter under snow. Summer soil–air CO₂ concentrations were positively correlated with soil moisture on daily and weekly scales, indicating that the Oi, Oe, and A horizons, where decomposition is accelerated by high-moisture conditions, contributed substantially to CO₂ emissions. This result is consistent with the short residence time (about 2 h) of CO₂ in the soil and larger emissions in shallow soil layers based on our diffusion model. We revealed for the first time that soil–air CO₂ concentrations in winter were correlated with both snow depth and wind speed. CO₂ transfer through the snow was hundreds of times the gas diffusion rates in the soil. Our estimate of the CO₂ efflux during the snow-cover season was larger than previous estimates at TKY, and confirmed the important contribution of the snow-cover season to the site’s carbon dynamics.     

Dual potential of microalgae as a sustainable biofuel feedstock and animal feed

The rise in global population has led to explorations of alternative sources of energy and food. Because corn and soybean are staple food crops for humans, their common use as the main source of dietary energy and protein for food-producing animals directly competes with their allocation for human consumption. Alternatively, de-fatted marine microalgal biomass generated from the potential biofuel production may be a viable replacement of corn and soybean meal due to their high levels of protein, relatively well-balanced amino acid profiles, and rich contents of minerals and vitamins, along with unique bioactive compounds. Although the full-fatted (intact) microalgae represent the main source of omega-3 (n-3) polyunsaturated fatty acids including docohexaenoic acid (DHA) and eicosapentaenoic acid (EPA), the de-fatted microalgal biomass may still contain good amounts of these components for enriching DHA/EPA in eggs, meats, and milk. This review is written to highlight the necessity and potential of using the de-fatted microalgal biomass as a new generation of animal feed in helping address the global energy, food, and environmental issues. Nutritional feasibility and limitation of the biomass as the new feed ingredient for simple-stomached species are elaborated. Potential applications of the biomass for generating value-added animal products are also explored.     

Secretion of inhibin in male Japanese quail (Coturnix japonica) from one week of age to sexual maturity

The objective of this study was to investigate the changes in secretion of inhibin and cellular localization of the inhibin alpha and inhibin/activin (beta(A) and beta(B)) subunits in male Japanese quail from 1 to 7 weeks after hatching. The post-hatch profile of plasma luteinizing hormone (LH), immunoreactive (ir) inhibin and testosterone were measured by radioimmunoassay. Testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against inhibin alpha, inhibin/activin beta(A) and inhibin/activin beta(B) from one week of age to sexual maturity. Testicular weight increased gradually until 4 weeks and abruptly increased from 5 weeks of age onwards. The plasma concentrations of LH and ir-inhibin increased significantly at 5 weeks of age, and the plasma concentration of testosterone increased significantly at 6 weeks of age. Pituitary contents of LH showed a steady increase until 6 weeks of age and then abruptly increased at 7 weeks of age. Coincident to the increase in plasma testosterone, the testicular contents of testosterone significantly increased from 5 weeks through sexual maturity. Immunohistochemically, localization of the inhibin/activin alpha, beta(A) and beta(B) subunits was found in the Sertoli and Leydig cells at all ages of development from one week of age to sexual maturity. These results suggest that Sertoli and Leydig cells are the major source of inhibin secretion during development in male Japanese quail.