Trace elements influenced by environmental changes in Lake Biwa: (I) Seasonal variations under suboxic hypolimnion conditions during 2007 and 2009

Dissolved oxygen (DO) in the Lake Biwa hypolimnion reached its lowest level of <1 mg kg^?1 in 2007. In this paper, we report the variations in the total dissolvable (TD), dissolved (D), and labile particulate (LP) fractions of Al, Si, P, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Mo, W, and U in Lake Biwa 2007 and 2009. Al and Fe species were predominantly in the form of LP-Al and LP-Fe and were strongly correlated with one another (r = 0.99), suggesting that the weathering of aluminous minerals and the supply of clay mineral particles are the main factors that influence the distributions of Al and Fe. Although D-Al increased in the summer epilimnion, D-Fe was relatively low, probably as a result of uptake by plants. Reductive release of Fe from the bottom was not seen. Mn was also dominated by LP-Mn, but this fraction showed a different distribution to those of LP-Al and LP-Fe. The D-Mn and LP-Mn concentrations varied by factors of 700–1000 and showed marked increases in the bottom water during stratification in 2007. We believe that Mn²⁺ was released from the sediments and oxidized by DO in the bottom water. Ni, Cu, Zn, and Cr, which exist as cationic species, had LP/TD ratios of 0.1–0.7 and relatively uniform distributions. Si, P, V, As, Mo, W, and U, which form oxoacid species, had LP/TD ratios of 0–0.8. Si, P, and As were characterized by nutrient-like profiles, V, W, and U showed summer maxima in the epilimnion, and Mo had a uniform distribution. TD-Mo increased in the bottom water along with TD-Mn, while TD-V and TD-W showed significant decreases. These results are likely attributable to differences in the adsorption of these elements onto manganese oxides and iron hydroxides.     

Urinary excretion of uric acid,allantoin, and 8-OH-Deoxyguanosine in uricase-knockout mice

ABSTRACT

Although uricase-knockout (Uox KO) mice are reported to develop uric acid (UA) nephropathy, those that mature without severe nephropathy could be useful for research into purine metabolism in humans. In this study, we measured the urinary excretion of creatinine, UA, allantoin, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) collected from Uox KO mice housed in metabolic cages. UA and allantoin were determined using liquid chromatography–mass spectrometry and creatinine and 8-OHdG were measured with a commercial kit. Uox KO mice excreted significantly higher levels of UA than wild-type mice (C57BL/6), while the excretion of allantoin was significantly lower. Urinary allantoin was detected in Uox KO mice despite a lack of uricase, which is the same as in humans. In contrast to the elevated levels of UA, the daily excretion of 8-OHdG, an oxidative stress marker, was lower in Uox KO mice. UA is thought to act as an anti-oxidizing agent in humans; thus, these results show that Uox KO mice are potential animal models for research into human purine metabolism.     

Synthesis of the (9R,13R)-isomer of LDS1, a flower-inducing oxylipin isolated from Lemna paucicostata

The first synthesis of the (9R,13R)-stereoisomer of LDS1, a flower-inducing oxylipin isolated from Lemna paucicostata, has been achieved from a known allylic alcohol by a seven-step sequence that involves the Horner–Wadsworth–Emmons olefination to construct its full carbon framework and an enzymatic hydrolysis of a penultimate methyl ester intermediate to provide the target molecule.     

FOXO1 delays skeletal muscle regeneration and suppresses myoblast proliferation

Unloading stress, such as bed rest, inhibits the regenerative potential of skeletal muscles; however, the underlying mechanisms remain largely unknown. FOXO1 expression, which induces the upregulated expression of the cell cycle inhibitors p57 and Gadd45α, is known to be increased in the skeletal muscle under unloading conditions. However, there is no report addressing FOXO1-induced inhibition of myoblast proliferation. Therefore, we induced muscle injury by cardiotoxin in transgenic mice overexpressing FOXO1 in the skeletal muscle (FOXO1-Tg mice) and observed regeneration delay in skeletal muscle mass and cross-sectional area in FOXO1-Tg mice. Increased p57 and Gadd45α mRNA levels, and decreased proliferation capacity were observed in C2C12 myoblasts expressing a tamoxifen-inducible active form of FOXO1. These results suggest that decreased proliferation capacity of myoblasts by FOXO1 disrupts skeletal muscle regeneration under FOXO1-increased conditions, such as unloading.     

Artificial cationic peptides that increase nuclease resistance of siRNA without disturbing RNAi activity

Properties of cationic peptides bearing amino or guanidino groups with various side chain lengths that bind to double stranded RNAs (dsRNAs) were investigated. Peptides with shorter side chain lengths effectively bound to dsRNAs (12mers) increasing their thermal stability. NMR measurements suggested that the cationic peptide binds to the inner side of the major groove of dsRNA. These peptides also increased the thermal stability of siRNA and effectively protected from RNase A digestion. On the other hand, both peptides containing amino groups and guanidine groups did not disturb RNAi activity.     

EcoBalance 2018—Nexus of ideas: innovation by linking through life cycle thinking (9–12 October 2018, Tokyo,Japan)

The International Journal of Life Cycle Assessment -     

Analysis of finger vein variety in patients with various diseases using vein authentication technology

In finger vein authentication technology, near‐infrared rays penetrate the finger and are absorbed by the hemoglobin in blood. The veins appear as dark areas. The finger vein pattern images of patients with various diseases were acquired; a new evaluation method applying image processing technique (“E value”) was developed, and it was examined whether the patterns have any characteristics differentiating them from those of healthy volunteers. As a result, low E values appeared in systemic sclerosis, mixed connective tissue disease, Sjögren's syndrome, and polymyositis/dermatomyositis. No statistical reduction in E value was shown in patients with rheumatoid arthritis, pernio (without rheumatic diseases), arteriosclerosis obliterans, diabetes, hypertension, hypothyroidism and alopecia areata. This technology could be used for screening and evaluation of some diseases and their conditions with impaired peripheral venous circulation. E value may be useful as an indicator of venous circulation.