A5023227044- Water Treatment and Disinfection
- Wastewater Treatment and Nitrogen Removal
- Pharmaceutical and Antibiotic Environmental Impacts
- Microbial Community Ecology and Physiology
- Antibiotic Resistance in Bacteria
- Fecal contamination and water quality
- Heavy metals in environment
- Urban Stormwater Management Solutions
- Water Quality Monitoring and Analysis
- Analytical chemistry methods development
- Environmental Toxicology and Ecotoxicology
- Water Quality and Pollution Assessment
- Microbial bioremediation and biosurfactants
- Constructed Wetlands for Wastewater Treatment
- Environmental Chemistry and Analysis
- Environmental DNA in Biodiversity Studies
- Mercury impact and mitigation studies
- Isotope Analysis in Ecology
- SARS-CoV-2 detection and testing
- Asphalt Pavement Performance Evaluation
- Water Systems and Optimization
- Antibiotics Pharmacokinetics and Efficacy
- Antibiotic Use and Resistance
- Chromium effects and bioremediation
- Vibrio bacteria research studies
The University of Tokyo
2016-2025
Nagasaki University
2024
Vietnam National University, Hanoi
2019-2022
National Defense Academy of Japan
2020
National Institute of Public Health
2007
Molecular changes in dissolved organic matter (DOM) from treatment processes at two drinking water plants Japan were investigated using unknown screening analysis by Orbitrap mass spectrometry. DOM formulas with carbon, hydrogen and oxygen (CHO–DOM) the most abundant class samples, over half of them commonly found both plants. Among processes, ozonation induced drastic to DOM. Mass peak intensities less saturated CHO–DOM (positive (oxygen subtracted double bond equivalent per carbon...
Tigecycline is important as a last-resort antimicrobial and effective against antimicrobial-resistant bacteria, such carbapenem-producing Enterobacterales (CPE), whose infections are difficult to treat with antimicrobials. Since 2019, mobile tigecycline resistance genes, tet (X) tmexCD-toprJ , their variants have been reported mainly from China, it has become understand epidemiological situation detailed genetic mechanisms.
Tigecycline resistance mediated by the mobile tigecycline-inactivating enzyme gene tet(X) in Gram-negative bacteria is an emerging concern for global public health. However, limited information available on distribution of natural environment. In this study, we investigated presence environmental bacteria. A carbapenem- and tigecycline-resistant Shewanella xiamenensis isolate (NUITM-VS1) was obtained from urban drainage Hanoi, Vietnam, March 2021. Whole-genome sequencing analysis performed...
Antimicrobial resistance (AMR) is a serious public health concern. Many countries have implemented AMR surveillance programs for humans and animals, but scheme monitoring in the environment has not yet been established. Class 1 integrons, which can acquire antimicrobial genes (ARGs) to gene cassettes, were proposed as candidate evaluate anthropogenic impacts on AMR. However, association between class integrons ARGs aquatic environments less studied requires further elucidation. This study...
To identify the microorganisms involved in benzene degradation, DNA-stable isotope probing (SIP) with 13C-benzene was applied to a methanogenic benzene-degrading enrichment culture. Pyrosequencing of ribosomal RNA (rRNA) gene sequences revealed that community structure highly complex spite 3-year incubation only benzene. The culture degraded 98% approximately 1 mM and mineralized 72% within 63 d. terminal restriction fragment length polymorphism (T-RFLP) profiles buoyant density fractions...
In premise plumbing, microbial water quality may deteriorate under certain conditions, such as stagnation. Stagnation results in a loss of disinfectant residual, which lead to the regrowth microorganisms, including opportunistic pathogens. present study, was investigated at eight faucets building over four seasons one year. Water samples were obtained before and after 24 h first 100 mL stagnation, total cell counts measured by flow cytometry increased 14- 220-fold with simultaneous...
Molecular-level characterization of dissolved organic matter (DOM) in different urban water resources (river water, groundwater, reclaimed and rainwater) was performed by Orbitrap Fourier transform mass spectrometry (FT-MS). The spectra, which were fingerprints DOM composition, clearly among samples. Based on accurate molecular determination, about 300 formulae identified. Most the molecules composed carbon, hydrogen oxygen. Molecular river consisted CHO mostly much less N- S-containing...
The health burden of waterborne nontuberculous mycobacteria (NTM) is a rising concern. While the water supply systems can serve as potential reservoir for NTM, their abundance, diversity, and transmission pathways remain unknown. This study aimed to characterize prevalence regrowth NTM in building system hospital where many M. abscessus were isolated from patients. depletion residual chlorine after stagnation warm at point use promoted significant microbial regrowth, including hospital....
The influence of backwashing on the biofilm community developed biological activated carbon (BAC) used in a drinking water treatment plant was investigated by means bacterial cell enumeration and terminal-restriction fragment length polymorphism (T-RFLP) fingerprinting analysis eukaryotic ribosomal RNA genes (rDNA). After backwashing, attached abundance top layer BAC bed decreased to 64% that before backwashing. level changes caused were examined through T-RFLP profiles. In 16S rDNA...