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Takatori S.,Osaka Prefectural Institute of Public Health | Akutsu K.,Osaka Prefectural Institute of Public Health | Kondo F.,Aichi Medical University | Ishii R.,Saitama Prefectural Institute of Public Health | And 2 more authors.
Chemosphere | Year: 2012

In vitro fertilization (IVF) is one of the most important treatments of infertility to provide a chance of conceiving. In IVF treatment, sperm are washed and motile sperm are isolated with sperm washing media (SWM) for the purpose of fertilization; fertilized ova are then incubated for a maximum of 5 or 6d in media for IVF (IVFM). The exposure of fertilized ova to chemicals via such media has not been studied. We determined the concentrations of two contaminants; di(2-ethylhexyl)phthalate (DEHP) and its hydrolyzed product mono(2-ethylhexyl)phthalate (MEHP) in IVFM, SWM, and protein sources (PS: human serum albumin or serum substitute) for IVFM and SWM. The DEHP and MEHP in these media were extracted by a liquid-liquid extraction method and their concentrations determined by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Fifteen IVFM, nine SWM, and six PS obtained in Japan were examined. The concentrations of DEHP and MEHP in IVFM and SWM were <10-114 and <2.0-263ngmL -1, respectively. The concentrations of both DEHP and MEHP were higher in the media containing PS than in those without PS. Either MEHP alone or both DEHP and MEHP were detected in PS. The concentrations of DEHP and MEHP in PS were <10-982 and 47.0-1840ngmL -1, respectively. The DEHP and MEHP detected in these media were derived from PS. This is the first study on the chemical contamination of IVFM, SWM, and PS. © 2011 Elsevier Ltd.


Yui T.,Chuo Livestock Hygiene Service Center | Yamamoto N.,Saitama Prefectural Institute of Public Health | Kon M.,Saitama Prefectural Institute of Public Health | Abe N.,Japan Institute for Environmental Sciences | And 2 more authors.
Parasitology Research | Year: 2014

We investigated the distribution of Cryptosporidium in pigs in Japan by immunofluorescence staining of fecal samples and characterization of isolates by multilocus sequencing. The 344 animals sampled on eight farms included pre-weaned piglets (<1 month old; n = 55), weaned piglets (1-2 months old; n = 65), finished pigs (2-4 months old, n = 105) and of 4-6 months old (n = 67), sows (n = 36), and boars (n = 16). Average prevalence of Cryptosporidium on farms was 32.6 %, ranging from 4.9 to 58.1 %, decreasing with animal age (prevalences of <1 month old, 1-2 months old, 2-4 months old, 4-6 months old, sows, and boars were 27.3, 47.7, 41.9, 22.4, 11.1, 18.8 %, respectively). Piglets (<1 and 1-2 months old) showing signs of diarrhea shed relatively more oocysts (5.28 in average log scale of oocysts per gram) in feces than piglets with normal or loose stools (those of 4.90). Thirty seven successful sequencing of the 18S ribosomal RNA gene among 62 examined samples revealed that all of the identified isolates were Cryptosporidium suis or Cryptosporidium scrofarum, which are generally specific to pigs, and that other species, such as zoonotic Cryptosporidium parvum, were absent. Interestingly, C. suis was frequently found in piglets younger than 2 months old, while C. scrofarum infection was more prevalent in older pigs which also showed increased prevalence of mixed C. suis and C. scrofarum infections. Sequencing of actin gene loci revealed the existence of variants of both Cryptosporidium species in pigs in Japan. Although the number of pigs examined in this study was relatively low, our results suggest that Cryptosporidium infection is widespread among pigs in Japan. In addition, the possibility of age-related specificity and pathogenicity in pig infections is also suggested. © 2013 Springer-Verlag Berlin Heidelberg.


PubMed | Otsuma Women's University, Hoshi University, Yamaguchi University, Meiji University and 7 more.
Type: | Journal: BioMed research international | Year: 2015

The regulation of transcription and genome stability by epigenetic systems are crucial for the proper development of mammalian embryos. Chemicals that disturb epigenetic systems are termed epimutagens. We previously performed chemical screening that focused on heterochromatin formation and DNA methylation status in mouse embryonic stem cells and identified five epimutagens: diethyl phosphate (DEP), mercury (Hg), cotinine, selenium (Se), and octachlorodipropyl ether (S-421). Here, we used human induced pluripotent stem cells (hiPSCs) to confirm the effects of 20 chemicals, including the five epimutagens, detected at low concentrations in maternal peripheral and cord blood samples. Of note, these individual chemicals did not exhibit epimutagenic activity in hiPSCs. However, because the fetal environment contains various chemicals, we evaluated the effects of combined exposure to chemicals (DEP, Hg, cotinine, Se, and S-421) on hiPSCs. The combined exposure caused a decrease in the number of heterochromatin signals and aberrant DNA methylation status at multiple gene loci in hiPSCs. The combined exposure also affected embryoid body formation and neural differentiation from hiPSCs. Therefore, DEP, Hg, cotinine, Se, and S-421 were defined as an epimutagen combination that is effective at low concentrations as detected in maternal peripheral and cord blood.


Wajima T.,Tokyo University of Pharmacy and Life Science | Chiba N.,Keio University | Morozumi M.,Keio University | Shouji M.,National Cancer Center Hospital | And 4 more authors.
Microbial Drug Resistance | Year: 2014

A GAS Surveillance Study Group was organized to analyze group A streptococci (GAS) isolated from patients with acute pharyngotonsillitis, with participating pediatricians submitting swab samples between April and October 2012. Molecular analysis of emm typing and multilocus sequence typing (MLST), as well as antimicrobial susceptibility testing, were carried out for 363 GAS isolates. Strains belonging to emm1 were most prevalent (25.6%), followed in turn by emm12 (23.7%), emm28 (16.3%), and emm89 (15.3%). In emm1, 87.2% of strains, typed as ST28 or ST661, showed macrolide (ML) resistance mediated by the mef(A) gene. In emm12 (ST36 and ST465), 64.3% of strains were resistant to MLs because of mef(A) or erm(B), as was also true for 81.7% of emm28 (ST52). In emm89 (ST101 and ST646), however, such resistance was not seen. Due to the high levels of ML resistance observed, GAS isolates from individuals with penicillin allergies need to be isolated and their antimicrobial susceptibility tested, rather than automatically giving the patient a ML. © Copyright 2014, Mary Ann Liebert, Inc. 2014.


Morita Y.,Tokyo Kasei University | Komoda E.,Tokyo Kasei University | Ono K.,Saitama Prefectural Institute of Public Health | Kumagai S.,University of Tokyo
Journal of the Food Hygienic Society of Japan | Year: 2011

We examined the survival of two biofilm-forming strains and two biofilm-deficient strains of non typhoid Salmonella (NTS) on stainless steel bolt threads under dry conditions. Five μL of tryptone soya broth or egg yolk emulsion containing NTS strains at a concentration of 9 log cfu/ mL was dropped onto the thread surfaces of hexagonal bolts. After inoculation, the bolts were screwed into the nuts, and then removed (Separate type) or not removed (Unit type). The two types of samples were kept in a dry environment (20.0-25.0°C, 2-15% humidity) and bacteria on the surfaces were periodically counted. Biofilm-forming strains were recovered from all samples after 336 days of incubation, but biofilm-deficient strains were isolated from only two of 8 samples after 336 days. This finding demonstrates that NTS can survive for approximately one year on bolt threads, providing direct evidence of the potential risk of constructions having crevices or uneven surfaces as possible contamination sources. The risk of cross-contamination may be higher for biofilm-forming strains than for biofilm-deficient strains.


Ishii R.,Saitama Prefectural Institute of Public Health | Takahashi K.,Saitama Prefectural Institute of Public Health | Matsumoto R.,Saitama Prefectural Institute of Public Health
Journal of the Food Hygienic Society of Japan | Year: 2011

A simple method using high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was investigated for the detection of the antiprotozoal drug imidocarb in 10 livestock and seafood products. Liquid chromatographic separation employed a TSK VMpak-25 column with ammonium acetate-acetonitrile as a mobile phase. Mass spectral acquisition was performed in the ESI positive-ion mode. Imidocarb was extracted from all samples using liquid extraction with acetonitrile under basic conditions. For samples other than honey, fatsoluble impurities were removed by acetonitrile-hexane partitioning. The salting-out technique was used for extraction from honey in order to improve the separation of the organic solvent and water added to the honey sample. The limit of quantitation was 0.005 μg/g (expressed as concentration in samples). The recoveries from all samples were 76-109%, and the repeatability and reproducibility were also satisfactory.


Takahashi K.,Saitama Prefectural Institute of Public Health
Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan | Year: 2013

A simple determination method of dinoseb and dinoterb in agricultural products, livestock products and seafood by LC-MS/MS was developed. Agricultural samples were extracted with acetone (in the case of rice, soybean and tea leaf, phosphoric acid was added). An aliquot of crude extract was partitioned with hexane and sat. sodium chloride solution. In the case of livestock products and seafood, samples were extracted with a mixture of acetone, hexane, water and sodium chloride, and the organic layer was collected. Clean-up was performed using a PSA mini column. The LC separation was performed on a C18 column with methanol-water (19 : 1) containing 0.005 v/v% acetic acid as a mobile phase, and MS with negative ion electrospray ionization was used for detection. The calibration curve was linear between 0.0005 to 0.04 μg/mL for each compound. Average recoveries (n=5) of dinoseb and dinoterb from 20 kinds of agricultural products, livestock products and seafood fortified at the MRLs were 77-111%, and the relative standard deviations were 2-15%. The limits of quantitation were 0.001 μg/g for both compounds.


Karahashi M.,Josai University | Ishii F.,Josai University | Yamazaki T.,Josai University | Imai K.,Saitama Prefectural Institute of Public Health | And 3 more authors.
Lipids | Year: 2013

The Goto-Kakizaki (GK) rat is an animal model for spontaneous-onset, non-obese type 2 diabetes. Despite abundant evidence about disorders in metabolism, little information is available about fatty acid metabolism in the liver of GK rats. This study aimed to investigate the characteristics of the fatty acid profile, particularly MUFA, and the mechanism underlying the alterations in fatty acid profiles in the liver of GK rats. The activities of enzymes that participate in the biosynthesis of MUFA, expressions of genes encoding these enzymes, and the fatty acid profile in the liver were compared with those of obese Zucker (fa/fa) (ZF) rats, which are obese and non-diabetic. Stearoyl-CoA desaturase (SCD) activity and SCD1 gene expression were considerably up-regulated in GK rats, and these levels were largely comparable to those in ZF rats. However, the proportions and contents of oleic acid and palmitoleic acid were very low considering the highly elevated activity of SCD in the liver of GK rats, when compared with ZF rats. Palmitoyl-CoA chain elongation (PCE) activity and fatty acid elongase (Elovl6) gene expression were markedly up-regulated in ZF rats, whereas PCE activity was up-regulated much less and Elovl6 gene expression was unchanged in GK rats. These results suggest the possibility that up-regulation of gene expression of Elovl6 along with SCD1 is indispensable to elevate the proportions and contents of oleic acid in the liver. © 2013 AOCS.


PubMed | Saitama Prefectural Institute of Public Health
Type: Journal Article | Journal: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan | Year: 2015

The purpose of the present study is to investigate the production of trans-1,3-pentadiene in a sorbic acid-containing food which was the subject of a complaint that it was off-flavor. Penicillium sp. was isolated from the off-flavor food. The isolated Penicillium sp. was identified as Penicillium chrysogenum by DNA sequencing of the internal transcribed spacer region and the D1/D2 region of the 28S subunit. When P. chrysogenum was cultured in the presence of potassium sorbate, trans-1,3-pentadiene was produced and detected by GC-MS after solid-phase micro extraction. The production of trans-1,3-pentadiene by P. chrysogenum in the culture solution was pH-dependent. These results suggest that the production of trans-1,3-pentadiene in the off-flavor food was mainly due to the decomposition of sorbic acid by P. chrysogenum.


PubMed | Saitama Prefectural Institute of Public Health
Type: Journal Article | Journal: Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan | Year: 2015

A method for the determination of ipfencarbazone in agricultural products, livestock products and seafood by LC-MS/MS was developed. Agricultural samples were extracted with acetone. An aliquot of crude extract was partitioned with n-hexane and sat. sodium chloride solution. Clean-up was performed using GC/PSA and C18 cartridges. In the case of livestock products and seafood, samples were extracted with a mixture of acetone and n-hexane, and the organic layer was collected. After acetonitrile-hexane partitioning, the extract was cleaned up using PAS and C18 cartridges. The gradient LC separation was performed on a C18 column with acetonitrile-water containing acetic acid as a mobile phase, and MS with positive ion electrospray ionization was used for detection. The average recoveries (n=5) of ipfencarbazone from 16 kinds of agricultural products, livestock products and seafood spiked at the MRLs or at the uniform limits (0.01 ppm) were 73-101%, and the relative standard deviations were 1.3-5.1%. The limit of quantitation of the developed method was 0.01 mg/kg for ipfencarbazone.

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