Fish assemblage structure response to seagrass bed degradation due to overgrazing by the green sea turtle Chelonia mydas at Iriomote Island,southern Japan

Ichthyological Research - The fish assemblage structure response to rapid degradation of Enhalus acoroides seagrass beds due to overgrazing by green sea turtles (Chelonia mydas) was investigated at...     

Corrected photochemical reflectance index (PRI) is an effective tool for detecting environmental stresses in agricultural crops under light conditions

Journal of Plant Research - High-throughput detection of plant environmental stresses is required for minimizing the reduction in crop yield. Environmental stresses in plants have primarily been...     

Curcumin attenuates oxidative stress following downhill running-induced muscle damage

Downhill running causes muscle damage, and induces oxidative stress and inflammatory reaction. Recently, it is shown that curcumin possesses anti-oxidant and anti-inflammatory potentials. Interestingly, curcumin reduces inflammatory cytokine concentrations in skeletal muscle after downhill running of mice. However, it is not known whether curcumin affects oxidative stress after downhill running-induced muscle damage. Therefore, the purpose of this study was to investigate the effects of curcumin on oxidative stress following downhill running induced-muscle damage. We also investigated whether curcumin affects macrophage infiltration via chemokines such as MCP-1 and CXCL14. Male C57BL/6 mice were divided into four groups; rest, rest plus curcumin, downhill running, or downhill running plus curcumin. Downhill running mice ran at 22 m/min, −15% grade on the treadmill for 150 min. Curcumin (3 mg) was administered in oral administration immediately after downhill running. Hydrogen peroxide concentration and NADPH-oxidase mRNA expression in the downhill running mice were significantly higher than those in the rest mice, but these variables were significantly attenuated by curcumin administration in downhill running mice. In addition, mRNA expression levels of MCP-1, CXCL14 and F4/80 reflecting presence of macrophages in the downhill running mice were significantly higher than those in the rest mice. However, MCP-1 and F4/80 mRNA expression levels were significantly attenuated by curcumin administration in downhill running mice. Curcumin may attenuate oxidative stress following downhill running-induced muscle damage.     

The role of Rubisco and cell walls in the interspecific variation in photosynthetic capacity

Photosynthetic capacity is known to vary considerably among species. Its physiological cause and ecological significance have been one of the most fundamental questions in plant ecophysiology. We studied the contents of Rubisco (a key enzyme of photosynthesis) and cell walls in leaves of 26 species with a large variation in photosynthetic rates. We focused on photosynthetic nitrogen-use efficiency (PNUE, photosynthetic rate per nitrogen), which can be expressed as the product of Rubisco-use efficiency (RBUE, photosynthetic rate per Rubisco) and Rubisco nitrogen fraction (RNF, Rubisco nitrogen per total leaf nitrogen). RBUE accounted for 70% of the interspecific variation in PNUE. The variation in RBUE was ascribed partly to stomatal conductance, and other factors such as mesophyll conductance and Rubisco kinetics might also be involved. RNF was also significantly related to PNUE but the correlation was relatively weak. Cell wall nitrogen fraction (WNF, cell wall nitrogen per total leaf nitrogen) increased with increasing leaf mass per area, but there was no correlation between RNF and WNF. These results suggest that nitrogen allocation to cell walls does not explain the variation in PNUE. The difference in PNUE was not caused by a sole factor that was markedly different among species but by several factors each of which was slightly disadvantageous in low PNUE species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.