Combined effects of EPS and HRT enhanced biofouling on a submerged and hybrid PAC-MF membrane bioreactor.

The goal of this study was to quantify and demonstrate the dynamic effects of hydraulic retention time (HRT), organic carbon and various components of extracellular polymeric substances (EPS) produced by microorganisms on the performance of submersed hollow-fiber microfiltration (MF) membrane in a hybrid powdered activated carbon (PAC)-MF membrane bioreactor (MBR). The reactors were operated continuously for 45 days to treat surface (river) water before and after pretreatment using a biofiltration unit. The real-time levels of organic carbon and the major components of EPS including five different carbohydrates (D(+) glucose and D(+) mannose, D(+) galactose, N-acetyl-D-galactosamine and D-galactose, oligosaccharides and L(-) fucose), proteins, and polysaccharides were quantified in the influent water, foulants, and in the bulk phases of different reactors.

A regional biogeography of shore molluscs: influence of the Kuroshio current and the two capes.

The regional pattern of shore molluscan assemblages was investigated along a 650-km coastline of the Kii Peninsula in central Japan. Hydrography of the coastal waters differed between three subareas, the Inner Kii Channel (IKC), the Outer Kii Channel (OKC), and the Sea of Kumano (SOK), which are demarcated by the two prominent capes, Cape Hinomisaki and Cape Shionomisaki. The water of OKC was warm, saline, and transparent compared to that of the other subareas, due to the influence of the intruding Kuroshio current.

Effect of photoreactivation on ultraviolet inactivation of Microcystis aeruginosa.

Microcystis aeruginosa forms algal bloom in lakes. They produce toxic compounds such as microcystin. Against such algal problems, the effect of UV treatment was examined.

Development of a real-time RT-PCR assay combined with ethidium monoazide treatment for RNA viruses and its application to detect viral RNA after heat exposure.

A method was developed for discriminating damaged viruses or naked viral RNA from intact viruses by ethidium monoazide (EMA) treatment before RT-PCR. The applied EMA treatment consisted of three steps: (1) EMA dose, (2) exposure to light, and (3) additional purification by spin-column gel filtration. Approximately 4-log reduction in viral RNA concentration was observed by adding a dose of 10 μg/mL-EMA with 300 s of light irradiation.

[Determination of substances in polylactic acid products for food-contact use and mutagenicity of their migration solutions].

Specification tests defined in the Japanese Food Sanitation Law were conducted on 7 polylactic acid food-contact products. Moreover, the content and migration of other compounds were examined by means of ICP-AES, GC/MS and mutagenicity tests. All products met their specifications, and migration levels of heavy metals were negligible.

Detection and genetic analysis of human sapoviruses in river water in Japan.

We investigated the prevalence of sapoviruses (SaVs) in the Tamagawa River in Japan from April 2003 to March 2004 and performed genetic analysis of the SaV genes identified in river water. A total of 60 river water samples were collected from five sites along the river, and 500 ml was concentrated using the cation-coated filter method. By use of a real-time reverse transcription (RT)-PCR assay, 12 (20%) of the 60 samples were positive for SaV.

Real-time PCR detection of adenoviruses, polyomaviruses, and torque teno viruses in river water in Japan.

The prevalence of DNA viruses in water from the Tamagawa River, Japan was quantitatively surveyed for 6months, from April to September 2003. A total of 18 river water samples were subjected to virus concentration method using an electronegative membrane, followed by DNA extraction and direct quantitative real-time polymerase chain reaction (qPCR) for DNA viruses. Adenoviruses of serotypes 40 and 41 were detected most frequently in the river water samples tested (61.

Detection of genogroup IV norovirus in wastewater and river water in Japan.

Aims: To test wastewater and river water in Japan for genogroup IV norovirus (GIV NoV).

Methods And Results: Influent and effluent samples from a wastewater treatment plant and the Tamagawa River water samples were collected monthly for a year. The water samples were concentrated by the adsorption-elution method, using an HA electronegative filter with acid rinse procedure, followed by quantitative detection of GIV NoV using TaqMan-based real-time RT-PCR.

Recovery of human norovirus from water by virus concentration methods.

The aim of this study was to evaluate the applicability of virus concentration methods to detect human norovirus (HuNoV) in water. One conventional virus concentration method using an electropositive filter (1MDS-method) and two methods developed by our research group using an electronegative filter (Mg-method and Al-method) were subjected to recovery tests of the HuNoV strain GII.4, which was obtained from a diarrhea patient, and poliovirus (PV) type 1 inoculated into 5 kinds of water samples.

First detection of genotype 3 hepatitis E virus RNA in river water in Cambodia.

To identify and describe hepatitis E virus (HEV) strains in aquatic environments in Cambodia, we collected two river-water samples from upstream and downstream sites along the Siem Reap River and examined them for HEV using a virus concentration method followed by TaqMan reverse transcription PCR and genetic analysis of the PCR product. Genotype 3 HEV strain was detected from the river-water sample collected from the river downstream, indicating that genotype 3 HEV strains are circulating in this region. To our knowledge, this is the first report demonstrating HEV contamination in aquatic environments in Cambodia.

Kinetics of Microcystis aeruginosa growth and intracellular microcystins release after UV irradiation.

The release of intracellular microcystins following ultraviolet (UV) irradiation was studied and modeled. Experimental results indicated that 90 mJ cm(-2) of UV fluence were required to inhibit Microcystis aeruginosa growth. The release of intracellular microcystins was also suppressed at higher UV fluence; microcystins concentrations in water did not increase as much in UV-irradiated samples as in controls.

Bacterial contamination of raw vegetables, vegetable-related water and river water in Ho Chi Minh City, Vietnam.

The study attempts to identify the potential routes of bacterial infection via consumption of raw vegetables, drinking water and vegetable-related water in Ho Chi Minh City (HCMC). Vegetables in the markets and restaurants had higher total coliforms and E. coli counts than the vegetables at the vegetable cultivation fields.

Quantification and genotyping of torque teno virus at a wastewater treatment plant in Japan.

Torque teno virus (TTV) DNA was quantitatively detected in influent and effluent samples collected from a wastewater treatment plant in Japan, with the highest concentration being 4.8 x 10(4) copies/liter. Genogroup-specific nested PCR demonstrated that TTV of genogroup 3 was the most abundant in wastewater among the five genogroups tested.

Development of sample storage methods for detecting enteric viruses in environmental water.

In a field survey of enteric viruses, water samples collected sometimes need to be stored for a long duration before analysis is performed. The aim of this study was to develop an appropriate sample storage method for detecting viruses in environmental water. Three types of sample storage methods were evaluated using MilliQ water, pond water, and treated sewage inoculated with poliovirus and norovirus: (i) storage followed by the full concentration procedure, (ii) filtration and storage followed by the remaining concentration procedure, and (iii) the full concentration procedure before storage.

Quantitative detection of sapoviruses in wastewater and river water in Japan.

Aims: To detect sapoviruses at a wastewater treatment plant (WWTP) and in a river in Japan, quantitatively.

Methods And Results: Influent and effluent samples at a WWTP and river water samples were collected monthly for 1 year. The water samples were subjected to virus concentration using an HA electronegative filter, followed by quantification of sapoviruses using real-time PCR.

Quantitative analysis of human enteric adenoviruses in aquatic environments.

Aims: The aim of this study was to determine human adenoviruses (HuAdVs) in aquatic environments by real-time polymerase chain reaction (PCR).

Methods And Results: In order to describe the ratio of enteric serotypes to the total HuAdVs, the primer set specific for the enteric serotypes 40 and 41 was used in parallel with the universal primer set for all 51 serotypes of HuAdVs. The enteric serotypes of HuAdVs were detected at the concentration of 7.

One-year monthly quantitative survey of noroviruses, enteroviruses, and adenoviruses in wastewater collected from six plants in Japan.

Sewerage systems are important nodes to monitor human enteric pathogens transmitted via water. A quantitative virus survey was performed once a month for a year to understand the seasonal profiles of noroviruses genotype 1 and genotype 2, enteroviruses, and adenoviruses in sewerage systems. A total of 72 samples of influent, secondary-treated wastewater before chlorination and effluent were collected from six wastewater treatment plants in Japan.

Identification of ISG12b as a putative interferon-inducible adipocytokine which is highly expressed in white adipose tissue.

Aim: A number of adipocytokines have been suggested to be involved in the disruption of glucose metabolism, and also in the development of various diabetic complications. We attempted to identify and analyze additional adipocytokines, to better understanding the roles of adipocytes and adipocytokines.

Methods: An oligo-capping signal sequence trap, developed in our laboratory for screening the cDNAs of secretory proteins, was used to sreen cDNAs expressed in mouse white adipose tissue.

Inactivation of Legionella pneumophila and Pseudomonas aeruginosa: evaluation of the bactericidal ability of silver cations.

In this study, silver cations dissolved as silver nitrate at various concentrations were exposed to Legionella pneumophila, Pseudomonas aeruginosa, and Escherichia coli to quantitatively estimate the bactericidal ability of silver. Observed data were analyzed using a newly developed model (Cs x T) that introduced a specific amount of chemisorbed silver onto a bacterial cell (Cs), which represented the chemisorption properties of silver on the bacterial cell body. Silver cations were rapidly chemisorbed onto bacterial cells after injection into samples, and Cs values (initial concentration of silver was 0.

Effects of low or medium-pressure UV irradiation on the release of intracellular microcystin.

UV irradiation could be an alternative growth inhibition treatment against toxic Microcystis blooms in lakes. This study examined the effect of UV irradiation on the release of toxic intracellular microcystin. Conventional algicidal treatment (e.

Recovery of naked viral genomes in water by virus concentration methods.

The recovery efficiency of naked poliovirus-RNA in water using virus concentration methods was determined to evaluate the possibility of detecting naked viral genomes. Two conventional virus concentration methods (1MDS-method and HA-method) and two methods developed by our research group (Mg-method and Al-method) were applied to recovery tests of poliovirus-RNA from four kinds of water sample, in parallel with recovery tests of poliovirus-virions. Mean recovery yields of poliovirus-RNA by the Mg-method were 5.

Seasonal profiles of human noroviruses and indicator bacteria in a wastewater treatment plant in Tokyo, Japan.

The seasonal profiles of microorganisms in raw sewage, secondary-treated sewage, and final effluent at a wastewater treatment plant in Tokyo, Japan, were quantitatively determined each month for one year, from July 2003 to June 2004. Human noroviruses, which were determined by real-time PCR, in raw sewage varied from 0.17-260 copies/mL for genotype 1 and from 2.

Effect of intracellular resuscitation of Legionella pneumophila in Acanthamoeba polyphage cells on the antimicrobial properties of silver and copper.

The property of Legionella pneumophila entering into a viable but noncultivable (VBNC) state under drinking water conditions (50 mL, pH 7.0, and 25 degrees C) and the intracellular resuscitation in Acanthamoeba polyphage cells were investigated. Then, the survival profiles of L.