Receptors for recombinant feline interferon-omega in hemocytes of the Japanese pearl oyster Pinctada fucata martensii

In a previous study we determined that administration of recombinant feline interferon-omega (rFeIFN-omega) could protect Japanese pearl oysters Pinctada fucata martensii from akoya-virus infection. Our results suggested that rFeIFN-omega enhanced the potential of agranulocytes to phagocytize necrotic cells and to produce collagen fibers that repair the lesions caused by the akoya-virus. In the present study, using an indirect immunofluorescence technique with an anti-rFeIFN-omega rabbit serum, we examined whether hemocytes bear receptors that bind rFeIFN-omega. rFeIFN-omega receptors were present on agranulocytes and bound rFeIFN-omega, and appeared as green fluorescent spots in the cytoplasm under a fluorescent microscope. Around 56% of agranulocytes in Japanese pearl oysters bore the rFeIFN-omega receptors.     

Ethylene glycol bis (beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) inhibits the growth of Escherichia coli at alkaline pH

The growth of Escherichia coli was inhibited by ethylene glycol bis (beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) in a medium of initial pH 8.8. The growth inhibition was reversed by the addition of CaCl(2). E. coli could grow in the presence of EGTA at pH values below 8. The concentration of free calcium ions increases with a decrease in medium pH because of a decrease in the calcium binding capacity of EGTA. So, although the results suggest that calcium ions are essential for the growth of E. coli, the minimum concentration required is very low.     

Treatment of Irradiated Mice with High-Dose Ascorbic Acid Reduced Lethality

Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure.     

Role of roots in differences in seed cadmium concentration among soybean cultivars—proof by grafting experiment

Soybean cultivars show significant differences in cadmium (Cd) concentrations in seeds, due primarily to genetics, not environmental factors. We previously suggested that low-Cd cultivars accumulate Cd in their roots and thus prevent its translocation to the rest of the plant. Through grafting experiments, we drew the following conclusions about Cd absorption and translocation: (1) The amount of Cd accumulated in shoots is determined by the Cd accumulation capacity of roots: cultivars with a small capacity to accumulate Cd in roots translocate more Cd and accumulate it in shoots; (2) The Cd concentration in shoots is determined by the Cd accumulation capacity of roots and the shoot productive ability of the scion cultivar; (3) The Cd tolerance of shoots differs among cultivars. Enrei, with a high-Cd accumulation capacity of roots, had a low Cd tolerance of shoots compared with Suzuyutaka and Hatayutaka, with a low Cd accumulation capacity of roots; (4) Cultivars differ in their distribution of Cd to seed; (5) These results show that seed Cd concentration is influenced by the differences among cultivars in ease of translocation of Cd to seed and in Cd accumulation capacity of roots.     

Reconstruction of paleodemographic characteristics from skeletal age at death distributions: perspectives from Hitotsubashi, Japan

This is a demographic exploration of the city of Edo, which reveals the changes that accompanied its urbanization and analyzes the skeletal remains of 207 individuals from a specific site in Tokyo (Hitotsubashi), using several paleodemographic approaches. A comparison of the three methods employed herein suggests that the Bayesian and maximum likelihood estimation techniques provide more plausible mortality patterns than the direct method of age estimation because the direct method of age estimation relies on published age intervals for the auricular surface and that would account for the underestimation of old people relative to the other two methods. Analyses using these new approaches indicate a short life span tendency for the people of Hitotsubashi. Although we cannot rule out methodological problems of adult-age estimation, one plausible interpretation of that life expectancy is an inadequate food supply and a poor public health situation. This study suggests that, in Tokugawa Japan, urbanization might have imposed health risks, increasing the risk of mortality. Analysis of demographic data from Hitotsubashi has refined our understanding on the impact of urbanization on the Edo period, and presents new perspectives on paleodemography in Japan.     

Construction of a tailor-made L (2S,3S)-butanediol dehydrogenase by exchanging domains between native structural analogs

The development of a stable L-BDH chimera was attempted by exchanging whole domains between two native structural analogs, L-BDH and meso-BDH, because the S-configuration specificity of L-BDH is valuable from the standpoint of its application but its activity is unstable, whereas meso-BDH is stable. The domain chimeras obtained indicated that the leaf-like structures constituting three domains were likely to be mainly associated with chiral recognition, and the fourth domain, the basic domain, is likely to be mainly associated with enzyme stability. A combination of the leaf domains of L-BDH and the basic domain of meso-BDH attained a sufficient level of practical use as an artificial L-BDH chimera, because the resulting enzyme had both stability and S-configuration specificity. However, the levels of stability and specificity were slightly lower than those of the respective enzymes from which they were derived.