No abstract

No abstract

The properties of a ferric ion-reducing system which catalyzes the reduction of ferric ion with elemental sulfur was investigated with a pure strain of ThiobaciUusferrooxidans. In anaerobic conditions, washed intact cells of the strain reduced 6 mol of Fe3+ with 1 mol of elemental sulfur to give 6 mol of Fe2 4 1 mol of sulfate, and a small amount of sulfite. In aerobic conditions, the 6 mol of Fe2+ produced was immediately reoxidized by the iron oxidase of the cell, with a consumption of 1.5 mol of oxygen. As a result, Fe2+ production was never observed under aerobic conditions. However, in the presence of 5 mM cyanide, which completely inhibits the iron oxidase of the cell, an amount of Fe21 production comparable to that formned under anaerobic conditions was observed under aerobic conditions. The ferric ion-reducing system had a pH optimum between 2.0 and 3.8, and the activity was completely destroyed by 10 min of incubation at 60°C. A short treatment of the strain with 0.5% phenol completely destroyed the ferric ion-reducing system of the cell. However, this treatment did not affect the iron oxidase of the cell. Since a concomitant complete loss of the activity of sulfur oxidation by molecular oxygen was observed in 0.5% phenol-treated cells, it was concluded that the ferric ion-reducing system plays an important role in the sulfur oxidation activity of this strain, and a new sulfur-oxidizing route is proposed for T. ferrooxidans.

Effect of heavy metal ions on the growth and the ironoxidizing activity of Thiobacillus ferrooxidans were investigated.

We conducted this study to compare survival rates and morbidity of persons with spinal cord injury (SCI) versus general population, and to clarify the risk of SCI persons. The subjects of this study were 960 men with SCI who had been accommodated in the eight Labor Accident Rehabilitation Centers in Japan during the period of 1965-1995. The surveyed items were the year of birth, the year of injury, level of spinal cord injury and survival status. The classification of cause of death was taken from ICD-10. The cumulative survival rate by life table method was calculated. In order to compare the risks of each cause of death in SCI persons with general population, causespecific standardized mortality ratio (SMR) was examined. The leading cause of death was malignant neoplasms at 28 persons, and SMR (general population=100) was 184, followed by the circulatory system disease, external cause (including suicide) and the genitourinary system disease. In the subgroups of malignant neoplasms, the SMR was 6,619 for cutaneous carcinomas and 1,482 for bladder carcinomas (p<0.01). Thus aging-related diseases which had close correlation with lifestyle and environment were the major cause of deaths in SCI persons.

Human noroviruses are the major cause of non-bacterial acute gastroenteritis worldwide. Since no therapeutic agent has been proven to prevent human norovirus infection yet, preventive healthcare interventions to block the infection routes play an important role in infection control. One of the possible infection routes of human noroviruses are through contaminated hands, but no hand antiseptics have been proven effective. Olanexidine gluconate is a new biguanide compound that has already been approved for sale as an antiseptic for the surgical field in Japan. A new hand antiseptic was developed using olanexidine gluconate in this study, and its virucidal efficacy against human noroviruses was evaluated using modified RT-qPCR that can account for genome derived from intact viruses using RNase A and photo-reactive intercalators. We tested the virucidal efficacy of five materials; two olanexidine gluconate antiseptics (hand rub formulation and surgical field formulation), two kinds of ethanol solutions at different pH (approx. 3 or 7), and a base component of olanexidine gluconate hand rub formulation against 11 human norovirus genotypes by culture-independent methods. The infectivity of murine norovirus (MNV), a surrogate for human norovirus, was significantly reduced after use of the antiseptics. The olanexidine gluconate hand rub demonstrated the strongest virucidal efficacy against human norovirus among the five tested materials. This study showed that olanexidine gluconate has the potential to become a strong tool for the prevention of human norovirus infection.

The formation mechanism of zeolite-templated carbons (ZTCs) is investigated. The carbon uptake into zeolite nanochannels during chemical vapor deposition (CVD) is found to proceed in the following three stages: (i) initial rapid carbon uptake from zeolite-particle surface to its center, (ii) gradual increase of carbon density at a constant rate, and (iii) termination of carbon deposition. The molecular-level structure evolution is also analyzed in detail. By CVD, curved nanographenes are formed inside the nanochannels of zeolite, and they are not perfectly connected each other. The subsequent heat treatment (>800 °C) coalesces the nanographenes to form a continuous 3D framework, and at the same time, a significant number of dangling bonds (non-terminated edge sites) are formed that are protected from air by the zeolite so that they are stable at room temperature. However on template removal, the dangling bonds react with ambient H 2 O or O 2 and are terminated by oxygen-functional groups or H. The dangling bonds in the carbon/zeolite composite can also be terminated by H when the composite is subjected to a H 2 treatment at 700 °C. In this case, the number of dangling bonds in the carbon/zeolite composite is decreased, and the addition of oxygen-functional groups when the template is removed becomes less significant.

No abstract