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After the Fukushima Nuclear Power Plant accident, most of radiocesium-contaminated soil generated from decontamination activities outside Fukushima prefecture has been stored at decontamination sites such as schools, parks and residential lands (storage at sites) according to the Decontamination Guidelines. However, additional exposure due to the present storage has not been evaluated. Moreover, entering storage sites, which is not restricted for storage at sites, was not considered in safety assessment conducted in the guidelines. To continue the storage and confirm the effectiveness, understanding of present possible exposures is important. In this study, we evaluated exposure doses for residents and users of storage sites based on the present situation. As a result, annual doses due to residence were 10−2 to 10−3 mSv y–1 and doses due to annual entries were of the order of 10−3 mSv y–1. Hence, we confirmed that the exposure due to present storage outside Fukushima is significantly <1 mSv y–1. [ABSTRACT FROM AUTHOR]

Sulfur is the seventh most abundant element measurable in the human body and is supplied mainly by the intake of methionine ( Met), an indispensable amino acid found in plant and animal proteins. Met controls the initiation of protein synthesis, governs major metabolic and catalytic activities, and may undergo reversible redox processes safeguarding protein integrity. Withdrawal of Met from customary diets causes the greatest downsizing of lean body mass following either unachieved replenishment (malnutrition) or excessive losses (inflammation). These physiopathologically unrelated morbidities nevertheless stimulate comparable remethylation reactions from homocysteine, indicating that Met homeostasis benefits from high metabolic priority. Inhibition of cystathionine-β-synthase activity causes the upstream sequestration of homocysteine and the downstream drop in cysteine and glutathione. Consequently, the enzymatic production of hydrogen sulfide and the nonenzymatic reduction of elemental sulfur to hydrogen sulfide are impaired. Sulfur operates as cofactor of several enzymes critically involved in the regulation of oxidative processes. A combination of malnutrition and nutritional deprivation of sulfur maximizes the risk of cardiovascular disorders and stroke, constituting a novel clinical entity that threatens plant-eating population groups. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) has been recognized as a smooth muscle relaxant. Cystathionine γ-lyase, which is localized to smooth muscle, is thought to be the major H2S-producing enzyme in the thoracic aorta. Here we show that 3-mercaptopyruvate sulfurtransferase (3MST) and cysteine aminotransferase (CAT) are localized to vascular endothelium in the thoracic aorta and produce H2S. Both 3MST and CAT were localized to endothelium. Lysates of vascular endothelial cells produced H2S from cysteine and α-ketoglutarate. The present study provides a new insight into the production and release of H2S as a smooth muscle relaxant from vascular endothelium. [ABSTRACT FROM PUBLISHER]

Abstract: Objective: Hypoxia-inducible factor 1 (HIF-1) regulates the expression of angiogenic growth factors. We analyzed the effect of intramuscular (i.m.) delivery of AdCA5, an adenovirus encoding a constitutively active form of the HIF-1α subunit, in a novel model of limb ischemia. Methods: AdCa5 or AdLacZ (6×108 pfu) was injected into male New Zealand White rabbits that were untreated or subjected to occlusion of the left superficial femoral artery by endovascular coils. Expression of mRNAs was quantified 1, 3, and 7 days after adenovirus injection into rabbits without occlusion. Calf blood pressure (BP), angiography, and immunohistochemical analyses were performed 14 days after arterial occlusion and adenovirus injection. Results: AdCA5 increased the expression of HIF-1α, monocyte chemotactic protein-1, placental growth factor, platelet-derived growth factor B, stromal-derived factor 1α, and vascular endothelial growth factor (VEGF) mRNA as well as HIF-1α and VEGF protein. On day 14, AdCA5-injected limbs showed improved calf BP ratios (0.89±0.13 vs. 0.51±0.05, p =0.02), angiographic perfusion scores (3.50±0.56 vs. 8.33±1.31, p =0.007), and distal deep femoral artery diameter ratio (1.84±0.25 vs. 0.93±0.22, p =0.02) relative to those receiving AdLacZ. The capillary/myocyte ratio (0.93±0.03 vs. 0.78±0.06, p =0.04) and arterial luminal area (0.32±0.05 mm2 vs. 0.21±0.03 mm2, p =0.04) were significantly increased in the AdCA5 group. Conclusion: In a model that resembles atherosclerotic obstruction of peripheral arteries in patients, the i.m. administration of AdCA5 promoted arteriogenic and angiogenic responses. [Copyright &y& Elsevier]