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Miwa Katagiri,1,2 Makoto Kuroda,2 Tsuyoshi Sekizuka,2 Norihide Nakada,3 Yukitaka Ito,4 Masanobu Otsuka,4 Manabu Watanabe,1 Shinya Kusachi1 1Department of Surgery, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, Japan; 2Laboratory of Bacterial Genomics, Pathogen Genomics Center, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo, Japan; 3Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, Otsu-shi, Shiga, Japan; 4Division of Clinical Microbiology Laboratory, Toho University Ohashi Medical Center, Meguro-ku, Tokyo, JapanCorrespondence: Miwa KatagiriDepartment of Surgery, Toho University Ohashi Medical Center, 2-22-36 Ohashi, Meguro-ku, Tokyo, 153-8515, JapanTel +81354333086Fax +81354333091Email girioyoshikazu0513@gmail.comMakoto KurodaLaboratory of Bacterial Genomics, Pathogen Genomics Center, National Institute of Infectious Diseases, 1-23-1 Toyama, Shinjuku-ku, Tokyo, 162-8640, JapanTel +81352851111Fax +81352851150Email makokuro@niid.go.jpBackground: Excrement containing antimicrobial-resistant bacteria (ARB) is discharged from the hospital sewage through wastewater treatment plants (WWTP) into rivers, increasing the antimicrobial resistance (AMR) burden on the environment.Purpose: We illustrate the contamination of hospital sewage tanks with ARB harboring antimicrobial resistance genes (ARGs) using comprehensive metagenomic sequencing. During the study period, we moved to a new hospital building constructed for renovation. Therefore, we investigated the difference in bacterial flora in the sewage tanks for each building with different departments, and the change in bacterial flora over time in new sewage tanks. Furthermore, we performed a comparative genome analysis of extended spectrum β-lactamase (ESBL)-producing organisms (EPOs) from hospital sewage and clinical samples. Residual antibiotics in the sewage tank were also measured.Methods: Metagenomic analysis was performed on the hospital sewage samples, followed by whole genome sequencing of EPOs.Results: The bacterial composition of new sewage tanks was comparable with that of old tanks within 1 month after relocation and was instantly affected by excrement. The bacterial composition of sewage tanks in the old and new buildings, containing rooms where seriously ill patients were treated, was similar. Selection on CHROMagar ESBL allowed detection of EPOs harboring blaCTX-M and carbapenemase genes in all sewage tanks. One of the sewage Escherichia coli strain comprising ST393 harboring blaCTX-M-27 corresponded to the clinical isolates based on core genome analysis. Moreover, the levels of levofloxacin and clarithromycin in the hospital sewage were 0.0325 and 0.0135 μg/mL, respectively.Conclusion: Hospital sewage was contaminated with many ARB species, ARGs and residual antibiotics, which can cause a burden on WWTP sewage treatment. The bacterial flora in the sewage tank was rapidly affected, especially by the ward with seriously ill patients. AMR monitoring of hospital sewage may help detect carriers prior to nosocomial ARB-associated outbreaks and control the outbreaks.Keywords: hospital sewage, antimicrobial resistance, antimicrobial resistance gene, metagenome analysis, whole genome sequencing, residual antimicrobial reagents

Interstitial-free steels containing 1–3% Ni were tensile tested. A clear yield point and yield point elongation were observed in each steel, even though they contained no solute carbon or nitrogen in the ferrite matrix. The mechanism could be explained by grain refinement strengthening enhanced by the addition of Ni, which is derived from the increase in Hall–Petch coefficient caused by grain boundary segregation. [ABSTRACT FROM AUTHOR]

The behavior of antibacterial triclosan, insect-repellent diethyltoluamide (DEET), anticonvulsant carbamazepine, and antipruritic crotamiton was investigated at two sewage treatment plants (STPs) to clarify their complete mass balance. Twenty-four-hour flow-proportional composite samples were collected from the influent and effluent of primary and final sedimentation tanks, a biofiltration tank and disinfection tanks. Sludge samples (i.e., activated and excess sludge) and samples of the return flow from the sludge treatment process were collected in the same manner. The analytes in both the dissolved and particulate phases were individually determined by a gas chromatograph equipped with mass spectrometer. Triclosan was dominantly detected in the particulate phase especially in the early stage of treatment (up to 83%) and was efficiently removed (over 90%) in STPs, mainly by sorption to sewage sludge. Limited removal was observed for DEET (55±24%), while no significant removal was demonstrated for crotamiton or carbamazepine. The solid-water distribution coefficients (Kd, n=4) for triclosan (log Kd: 3.7-5.1), DEET (1.3-1.9) and crotamiton (1.1-1.6) in the sludge samples are also determined in this study. These findings indicate the limitations of current sewage treatment techniques for the removal of these water-soluble drugs (i.e. DEET, carbamazepine, and crotamiton). [ABSTRACT FROM AUTHOR]

The occurrence of 70 pharmaceutical and personal care products (PPCPs) was investigated in the Tone River. The river has the largest basin in Japan, and the water is utilized not only for farming, but also as a source of water supply. One day in both January and October 2006, surface waters in the river and its tributaries and effluents from sewage treatment plants (STPs) directly discharging into the Tone River were collected, the location of which ranged over 150 km along the river. The 70 PPCPs in the samples were concentrated by solid phase cartridge and were measured by LC-MS/MS using three analytical methods. Fifty-seven PPCPs were detected in one or more samples. Bezafibrate, caffeine, carbamazepine, clarithromycin, crotamiton and sulpiride were frequently detected. Mass flow profiles of some PPCPs (e.g., crotamiton) were comparable to cumulative inhabitants in the basin, suggesting that these PPCPs could be markers of population. Total load of each PPCP into the basin from upstream, the tributaries, and the STPs were calculated. The contribution of selected PPCPs from the tributaries with lower sewerage system coverage was dominant compared to those from upstream and the STPs, suggesting the installation of sewerage systems is necessary to reduce the load of PPCPs in the Tone River basin. [ABSTRACT FROM AUTHOR]

Residual pharmaceutical products in sewage and other water environments have recently become a serious social problem in advanced countries. Among these pharmaceutical products, antibiotics have attracted special attention due to their serious impact on the ecosystem and connections to the emergence of drug-resistant bacteria. Our research intended to develop a new method to analyse the three antibiotics estimated to be released out of the body in large amounts in Japan; levofloxacin (LVFX), clarithromycin (CAM) and azithromycin (AZM), and survey the state of pollution in the sewerage. The concentrations of the water-phase antibiotics LVFX, CAM and AZM were measured in each process of activated sludge process in six wastewater treatment plants. Liquid chromatography tandem mass spectrometry (LC/MS/MS) was used to analyse solutions of the antibiotics after pretreatment with a solid phase extraction. The limits of quantification and the average recoveries for these antibiotics in the influent were 1.2 to 29 ng/L and 46 to 93%, respectively. In the influent, LVFX, CAM and AZM were detected at concentrations of 552, 647 and 260 ng/L, respectively, while their removal efficiencies were 42, 43 and 49%, respectively. Although the CAM and AZM concentrations decreased as the treatment progressed, it was shown that the LVFX concentration increased in activated sludge reactors in some cases. Despite differences in octanol-water partition coefficients among LVFX, CAM and AZM, their removal efficiency showed no major difference. This indicates that this removal phenomenon cannot be explained by simple adsorption by the activated sludge. [ABSTRACT FROM AUTHOR]

Understanding of the fate of oestrogen and oestrogenic compounds is important in improving the removal efficiency for oestrogens in wastewater treatment plants (WWTPs). In this study an attempt was made to clarify the fate of oestrogen, oestrogen sulphates, and oestrogenic compounds (synthetic oestrogen, nonylphenol and its relatives) by an instrumental analysis, and the fate of oestrogenicity by an in vitro assay. The investigation was conducted in an activated sludge WWTP in winter and summer, focusing on identification of the primary substances that induce oestrogenicity. Wastewater samples were analysed by employing the silica-gel fractionation technique in conjunction with two-step column chromatography. The results revealed that, in winter, the WWTP efficiencies for the removal of nitrogen and oestrogens decreased and the oestrone level increased with the progress of the treatment. Oestrone and oestrogenic substances are likely to circulate between the aeration tank and the final sedimentation tank. In summer, however, these compounds were effectively removed in the WWTP. The results of the column chromatography coupled with the bioassay suggested that E1 and E2 are the predominant contributors to the oestrogenicity in the influent, return sludge and effluent of the WWTP. The measurement by the instrumental analysis supported these findings. [ABSTRACT FROM AUTHOR]

Contamination of surface waters by pharmaceutical chemicals is an emerging environmental problem. This study evaluated the toxic effects of the antibacterial agents levofloxacin (LVFX) and clarithromycin (CAM), which are widely used in Japan, on aquatic organisms. Ecotoxicity tests using a bacterium, alga and crustacean were conducted. Microtox test using a marine fluorescent bacterium showed that LVFX and CAM have no acute toxicity to the bacterium. From the results of the Daphnia immobilisation test, LVFX and CAM did not show acute toxicity to the crustacean. Meanwhile, an algal growth inhibition test revealed that LVFX and CAM have high toxicity to the microalga. The phytotoxicity of CAM was about 100-fold higher than that of LVFX from a comparison of EC50 (median effective concentration) value. From the Daphnia reproduction test, LVFX and CAM also showed chronic toxicity to the crustacean. Concentrations of LVFX and CAM in the aquatic environment were compared with PNEC (predicted no effect concentration) to evaluate the ecological risk. As a result, the ecological risk of LVFX is considered to be low, but that of CAM is higher, suggesting that CAM discharged into an aquatic environment after therapeutic use may affect organisms in the aquatic environment. [ABSTRACT FROM AUTHOR]

Estrogen-like substances have been suspected to cause feminization of wild fish in rivers in Japan. To elucidate the influence of estrogen-like substances on fish in river, we have started to develop the on-site continuous fish exposure system using medaka Oryzias latipes that were placed in water quality monitoring stations along a river. Adult male medaka were exposed to the river water in a glass exposure tank placed in the monitoring stations. Flow rate of water and water temperature were controlled at 30 L/hour and 26 °C respectively, and a light: dark cycle was maintained 16:8 hours. A commercial diet free from phytoestrogens was fed 4 times in a day using automatic feeder. After 2-week exposure, hepatic vitellogenin concentration of each male medaka was measured. The exposure tests were repeatedly performed at both the upstream and the downstream of sewage treatment plants along the River Tama which is a representative urbanized river in Japan. At the control site Haijimabashi monitoring station, vitellogenin was not detected in male medaka. On the other hand, at the Ishihara monitoring station which is the most downstream in this test area, every male medaka were produced vitellogenin in the test performed in the spring of 2004. As the results of the water quality analysis, it could be inferred that the estrone derived from effluents of sewage treatment plants caused the feminization of male medaka. The reason why the concentrations of the estrone and the estrogenic activity using DNA recombinant yeast varied in proportion to the electric conductivity of river water measured at the water quality monitoring station. Furthermore, after continuous 2-week exposure, the vitellogenin production of male medaka was reduced similar to the decrease of the concentrations of the estrone and the estrogenic activity of river water. [ABSTRACT FROM AUTHOR]

Abstract Background To elucidate relations of invasion of ulcerative colitis (UC)-associated carcinoma with its prognosis, the characteristics of invasive fronts were analyzed in comparison with sporadic colonic carcinomas. Methods Prognoses of 15 cases of UC-associated colonic carcinoma were compared with those of sporadic colon carcinoma cases, after which 75 cases of sporadic invasive adenocarcinoma were collected. Tumor budding was examined histologically at invasive fronts using immunohistochemistry (IHC) of pancytokeratin. Expressions of beta-catenin with mutation analysis, CD44 extracellular domain, Zo-1, occludin, matrix matalloproteinase-7, laminin-5γ2, and sialyl Lewis X (LeX) were immunohistochemically evaluated. Results UC-associated carcinoma showed worse prognosis than sporadic colon carcinoma in all the cases, and exhibited a tendency to become more poorly differentiated when carcinoma invaded the submucosa or deeper layers than sporadic carcinoma. When the lesions were compared with sporadic carcinomas considering differentiation grade, reduced expression of CD44 extracellular domain in UC-associated carcinoma was apparent. Laminin-5γ2 and sialyl-LeX expression showed a lower tendency in UC-associated carcinomas than in their sporadic counterparts. There were no differences in the numbers of tumor budding foci between the two lesion types, with no apparent relation to nuclear beta-catenin levels in IHC. Conclusions UC-associated carcinoma showed poorer differentiation when the carcinoma invaded submucosa or deeper parts, which may influence the poorer prognosis. The invasive behavior of UC-associated carcinoma is more associated with CD44 cleavage than with basement membrane disruption or sialyl-Lewis-antigen alteration.

An InGaN multiple-quantum-well light-emitting diode (LED) containing a GaN/AlGaN distributed Bragg reflector has been grown on a sapphire substrate by metalorganic chemical vapor deposition. Comparing with the conventional LED, the output power has been improved from 79 to 120 μW under 20 mA direct current biasing condition and the external quantum efficiency has been also improved from 0.16% to 0.23% under 10 mA dc current. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]