Publications by authors named "Miho Nomura"
NPPs (Non-phthalate plasticizers) are used as alternative plasticizers to phthalate esters, but there is limited knowledge on environmental residues, and they have not been reported in Japan. A method to analyze NPPs in seawater using solid-phase extraction was developed, and the residual burden of Diisobutyl adipate (DIBA), Acetyl tributyl citrate (ATBC), Di-(2-ethylhexyl) adipate (DEHA), Di-(2-ethylhexyl) sebacate (DEHS) and Trioctyl trimellitate (TOTM) in seawater and sediment from the Osaka Bay was measured. Using an Oasis Max column and acetone as the eluting solvent, the recovery of the target substances in seawater is >68 %.
View Article and Find Full Text PDFA previous study suggested that inflammatory bowel disease (IBD) patients have low plasma levels of trimethylamine N-oxide (TMAO). In the present study, we examined this hypothesis using Mendelian randomization analysis. We used summary statistics data for single-nucleotide polymorphisms associated with plasma levels of TMAO, and the corresponding data for IBD from a genome-wide association meta-analysis of 59,957 individuals (25,042 diagnosed IBD cases, 34,915 controls).
View Article and Find Full Text PDFArticle Synopsis
- - The study investigated the effects of acetyl tributyl citrate (ATBC), a nonphthalate plasticizer, on sex hormone activity and gonadal differentiation in fish, particularly Japanese medaka.
- - Exposure to ATBC showed no significant changes in the normal development of testes and ovaries; it did not induce intersex conditions or alter sex differentiation in medakas.
- - While ATBC reduced the expression of certain liver biomarker genes in XX medakas and showed no change in XY medakas, it suggested a lack of estrogenic activity but possible weak androgenic effects.
Purpose: Observational studies have suggested that polyunsaturated fatty acids (PUFAs) decrease the risk of anorexia nervosa (AN). In the present study, we examined this hypothesis using a Mendelian randomization analysis.
Methods: We used summary statistics for single-nucleotide polymorphisms associated with plasma levels of n-6 (linoleic acid and arachidonic acid) and n-3 PUFAs (alpha-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid, and docosahexaenoic acid) and the corresponding data for AN from a genome-wide association meta-analysis of 72,517 individuals (16,992 diagnosed AN cases and 55,525 controls).
Effects of non-phthalate plasticizer bis(2-ethylhexyl) sebacate (DEHS) on the endocrine system in Japanese medaka (Oryzias latipes).
Comp Biochem Physiol C Toxicol Pharmacol
February 2023
Article Synopsis
- Water pollution from plasticizers, particularly phthalates, poses a significant environmental threat as they can disrupt endocrine systems in animals.
- This study focused on the non-phthalate plasticizer DEHS and its effects on gene expression related to thyroid hormones and reproduction in Japanese medaka fish, finding that DEHS suppressed certain thyroid-related gene expression and negatively impacted swimming performance.
- The research represents the first evidence that DEHS can interfere with thyroid-related metabolism in fish, while not significantly affecting reproduction-related gene expression.
Bisphenol A alters sexual dimorphism and gene expression in marine medaka Oryzias melastigma.
Environ Sci Pollut Res Int
February 2023
Article Synopsis
- Bisphenol A (BPA) is found in both freshwater and marine environments and is known to disrupt endocrine systems, but its long-term toxicity in marine fish, specifically the male marine medaka, has not been fully established.
- In experiments, exposure to BPA led to the development of testis-ova and alterations in male anal fin shapes toward more female characteristics, indicating that anal fin shape is a particularly sensitive indicator of BPA exposure.
- The study also found that BPA exposure decreased the expression of gonadal soma-derived factor (gsdf) and increased liver vitellogenin (vtg) expression in a dose-dependent manner, suggesting these factors could serve as useful biomarkers for assessing the impact of estrogenic endocrine disruptors in
Pollution of water bodies with plasticizers is a serious environmental problem worldwide. In this study, we investigated the effects of plasticizers bis-(2-ethylhexyl) phthalate (DEHP) and bis-(2-ethylhexyl) adipate (DEHA) in Japanese medaka (Oryzias latipes). DEHP significantly increased the expression of all the genes tested: thyroid stimulating hormone beta subunit (tshβ-like), tshβ, deiodinase 1 (dio1), deiodinase 2 (dio2), and thyroid hormone receptor alpha (trα) and beta (trβ).
View Article and Find Full Text PDFWe examined ingestion and retention rates of microplastics (MPs) by two freshwater (Japanese medaka and zebrafish) and two marine fish species (Indian medaka and clown anemonefish) to determine their color preferences and gastrointestinal-tract retention times. In our ingestion experiments, clown anemonefish ingested the most MP particles, followed by zebrafish, and then Japanese and Indian medaka. Next, we investigated color preferences among five MP colors.
View Article and Find Full Text PDFWe compared the influence of thyroid hormone-disrupting chemicals (heptafluorobutanoic acid, PFBA and tris[1,3-dichloro-2-propyl] phosphate, TDCPP) and thyroid hormone (3,3',5-triiodo-L-thyronine, T3) on swim bladder inflation and thyroid hormone-related gene expression in Japanese medaka and zebrafish. The swim bladder of most larvae had inflated at 4 h post hatching (hph) in Japanese medaka and at 48 hph in zebrafish in controls. In both fish species, the swim bladder inflation was inhibited in larvae exposed to PFBA (lowest observed effect concentration [LOEC] in medaka: 40 mg/L; in zebrafish: 80 mg/L), TDCPP (LOEC in medaka: 1 mg/L; in zebrafish: 0.
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