Long-term Performance of Repairs to Reinforced Concrete Exposed to Coastal Conditions

Reinforced concrete (RC) specimens were treated using different combinations of surface coating and/or patch repair methods and materials, left in a coastal region with frost damage risk, and their properties characterized after 25 years of exposure. Specimens were prepared by chipping away concrete from one section of concrete block with embedded reinforcement bars to expose the bars, followed by patch repair and then surface coating. Four types of material were used for patch repair: cement mortar, styrene-butadiene rubber (SBR) polymer cement mortar, rust-resistant SBR polymer cement mortar, and lightweight epoxy mortar. Two types of material were used for surface coating: multi-layer textured and thin textured coating. Following exposure, cracks were visible only on the surfaces of untreated specimens, apparently due to rebar corrosion; they were absent from all specimens that had undergone surface coating and/or patch repair. In addition, the corrosion resistance of these methods and materials was investigated by measuring and comparing the surface areas of corroded rebar between three segments: the repaired part, the unrepaired part, and the boundary between them. Concrete carbonation and rebar corrosion were greatly dependent on surface coating material, with the multilayer-textured coating especially effective at blocking chloride penetration. In addition, rebar corrosion was more effectively prevented by patch repair with the SBR polymer cement mortar than with the lightweight epoxy mortar

Coping Behaviors and Collaboration among Staff of Multiple Occupation Classifications during Norovirus

In December 2012 a norovirus infection outbreak occurred in the Orthopedic Surgery Ward of Hospital A in Japan. This study aims to establish details of coping behaviors used by nurses, physicians, physiotherapists, and pharmacists of the facility, and examine the issues involved in infection control by team collaboration as well as the ways employed to deal with the infections. Participants in this study were thirty-seven medical professionals who were working in the Orthopedic Surgery Ward of Hospital A at the time the infection outbreak occurred, and who were still working there when the interviews were conducted. Interviews were conducted from January to April 2015, and the data from the interviews were analyzed using the “Trend Search 2008” text mining software. As a result of the analysis it was found that the nurses primarily communicated information by passing messages to the nurses who took over the duty at shift changes, but did not pass on the information to staff in other occupations or to the ward as a whole. The nurses clearly remembered that the ward was closed and it was a difficult experience, but did not remember details of the patients they were in charge of. The physicians clearly remembered individual patients they were in charge of, but they were not aware of the situation and state throughout the ward. The findings suggest that this difference is due to the differences in the occupational nature and sense of values of the staff involved. It is also found that physiotherapists did not feel a sense of crisis about the norovirus outbreak because they felt the patients in the ward appeared to be in better condition than patients in other wards, and that pharmacists lacked communication with staff in other occupations because they usually have heavy workloads. In concept mappings of physicians, physiotherapists, and pharmacists, the keyword places in the center of the maps, and is linked to and . Because the nurse plays a central role to report information among the four occupations, nurses should be aware of and assigned to play the role to coordinate team collaboration

Role of CFTR in Campylobacter jejuni infection

Campylobacter jejuni (C. jejuni) is gastroenteritis inducible food-born pathogen. Invasion and adhesion process are essential for leading gastroenteritis in C. jejuni infection process. As against bacterial strategy for efficacy invasion and adhesion, mucosal layer play a key role in defense systems, which modulated by several ion channels and transporters mediated water flux on the intestine. Cystic fibrosis transmembrane conductance regulator (CFTR) play the main role in waterfulux in intestine, and it closely related with bacterial clearance. We previously reported that C. jejuni infection suppresses CFTR channel activity in intestinal epithelial cells, however the mechanism and importance of this suppression is unclear. This study seeks to elucidate the role of CFTR in C. jejuni-infection. Using HEK293 cells that stably express wild type and mutated CFTR, we found that CFTR attenuated C. jejuni invasion, it was not involved bacterial adhesion or intracellular survival but associated with microtubule-dependent cellular transport. Moreover we revealed that CFTR attenuated function of microtubule motor protein but not microtubule stability, which causes inhibition of C. jejuni-invasion. Meanwhile, the CFTR mutant G551D-CFTR, which has defects in channel activity, suppressed C. jejuni-invasion, whereasΔF508-CFTR, which has defects in maturation, did not suppress, suggesting that CFTR suppression of C. jejuni-invasion is related to CFTR maturation but not channel activity. Taken together, mature CFTR inhibited C. jejuni invasion by regulating microtubule-mediated pathways. We suggest that CFTR plays a critical role in cellular defenses against C. jejuni-invasion, and CFTR suppression may be an initial step in promoting cellular invasion during C. jejuni-infection

Campylobacter jejuni感染はT-84細胞におけるCFTR活性化によるCl⁻分泌亢進を抑制する

Campylobacter jejuni causes foodborne disease associated with abdominal pain, gastroenteritis, and diarrhea. These symptoms are induced by bacterial adherence and invasion of host epithelial cells. C. jejuni infection can occur with a low infective dose, suggesting that C. jejuni may have evolved strategies to cope with the bacterial clearance system in the gastrointestinal tract. The mucosa layer is the first line of defense against bacteria. Mucus conditions are maintained by water and anion (especially Cl-) movement. Cystic fibrosis transmembrane conductance regulator (CFTR) is the main Cl- channel transporting Cl- to the lumen. Mutations in CFTR result in dehydrated secreted mucus and bacterial accumulation in the lungs, and recent studies suggest that closely related pathogenic bacteria also may survive in the intestine. However, the relationship between C. jejuni infection and CFTR has been little studied. Here, we used an 125I- efflux assay and measurement of short-circuit current to measure Cl- secretion in C. jejuni-infected T-84 human intestinal epithelial cells. The basic state of Cl- secretion was unchanged by C. jejuni infection, but CFTR activator was observed to induce Cl- secretion suppressed in C. jejuniinfected T-84 cells. The suppression of activated Cl- secretion was bacterial dose-dependent and duration-dependent. A similar result was observed during infection with other C. jejuni strains. The mechanism of suppression may occur by affecting water movement or mucus condition in the intestinal tract. A failure of mucus barrier function may promote bacterial adhesion or invasion of host intestinal epithelial cells, thereby causing bacterial preservation in the host intestinal tract

タイトジャンクションは極性化上皮細胞においてCampylobacter jejuniの細胞側面からの効率的な侵入を妨げ炎症によるバリアの破綻は菌の侵入を促進する

Campylobacter jejuni invasion is closely related to C. jejuni pathogenicity. The intestinal epithelium contains polarized epithelial cells that form tight junctions (TJs) to provide a physical barrier against bacterial invasion. Previous studies indicated that C. jejuni invasion of non-polarized cells involves several cellular features, including lipid rafts. However, the dynamics of C. jejuni invasion of polarized epithelial cells are not fully understood. Here we investigated the interaction between C. jejuni invasion and TJ formation to characterize the mechanism of C. jejuni invasion in polarized epithelial cells. In contrast to non-polarized epithelial cells, C. jejuni invasion was not affected by depletion of lipid rafts in polarized epithelial cells. However, depletion of lipid rafts significantly decreased C. jejuni invasion in TJ disrupted cells or basolateral infection and repair of cellular TJs suppressed lipid raft-mediated C. jejuni invasion in polarized epithelial cells. In addition, pro-inflammatory cytokine, TNF-a treatment that induce TJ disruption promote C. jejuni invasion and lipid rafts depletion significantly reduced C. jejuni invasion in TNF-a treated cells. These data demonstrated that TJs prevent C. jejuni invasion from the lateral side of epithelial cells, where they play a main part in bacterial invasion and suggest that C. jejuni invasion could be increased in inflammatory condition. Therefore, maintenance of TJs integrity should be considered important in the development of novel therapies for C. jejuni infection

Infection risk in hemodialysis patient

Chronic care patients undergoing hemodialysis for treatment of end-stage renal failure experience higher rates of bloodstream-associated infection due to the patients' compromised immune system and management of the bloodstream through catheters. Staphylococcus species are a common cause of hemodialysis catheter-related bloodstream infections. We investigated environmental bacterial contamination of dialysis wards and contamination of hemodialysis devices to determine the source of bacteria for these infections. All bacterial samples were collected by the swab method and the agarose stamp method. And which bacterium were identified by BBL CRYSTAL Kit or 16s rRNA sequences. In our data, bacterial cell number of hemodialysis device was lower than environment of patient surrounds. But Staphylococcus spp. were found predominantly on the hemodialysis device (46.8%), especially on areas frequently touched by healthcare-workers (such as Touch screen). Among Staphylococcus spp., Staphylococcus epidermidis was most frequently observed (42.1% of Staphylococcus spp.), and more surprising, 48.2% of the Staphylococcus spp. indicated high resistance for methicillin. Our finding suggests that hemodialysis device highly contaminated with bloodstream infection associated bacteria. This study can be used as a source to assess the risk of contamination-related infection and to develop the cleaning system for the better prevention for bloodstream infections in patients with hemodialysis

Promotion of Seedling Growth of Seeds of Rice (Oryza sativa L. cv. Hitomebore) by Treatment with H2O2 before Sowing

High germinability of seeds and establishment of young seedlings in rice (Oryza sativa L.) are necessary for direct seeding in paddy fields. We investigated whether germinability and seedling growth were promoted by treatment of rice seeds (cv. Hitomebore) with hydrogen peroxide solution (H2O2) during the imbibition for 24 h. H2O2 treatment with 50 mM H2O2 promoted seed germination, and seedling growth (shoot length, root length and shoot fresh weight) in agar culture under a low temperature condition (18°C day/14°C night). Seedling growth was promoted by H2O2 treatment not only under the low-temperature condition but also under a normal (23°C day/18°C night) temperature condition. Furthermore, H2O2 treatment promoted seedling growth under a flooding condition in a greenhouse. These results suggest that H2O2 treatment of rice seeds during the imbibition is advantageous for direct seeding. We discussed the relation between the promotion of the seed germinability and the seedling growth under a low-temperature condition, and the expression of some genes encoding ROS scavenger enzymes induced by H2O2 treatment

Feasibility study on real-time γ-ray spectrum / dose measurement system

Recently, medical applications of radiation have been widely spread. However, exposure of medical staffs is sometimes not focused on because treatment of patients is the first priority. It is thus important to decrease exposure for them as much as possible. The purpose of this study is to develop a system which can measure energy spectrum and dose of gamma-rays at the same time in real time in medical application spots. As a result, the medical staff could be guided to aware the risk of radiation and finally the exposure dose to them could be suppressed substantially. We first decided to use a CsI(Tl) scintillator as the gamma-ray detection device. A Multi-Pixel Photon Counter (MPPC) was attached to the scintillator to detect gamma-ray signals. Pulse height spectra were measured with several standard gamma-ray sources. The detection efficiency and energy resolution were deduced from the measured results and the detection efficiency was compared with the calculation result by MCNP5. After evaluating the response function, the energy spectrum was derived with the spectrum type Bayesian estimation and the sequential Bayesian estimation procedure. From the result, it was confirmed that the sequential Bayesian estimation could be applied to real time measurement of gamma-ray energy spectrum and dose