1,393 results match your criteria: "Tokyo University of Marine Science[Affiliation]"

Microplastic pollution in marine environments poses significant environmental risks due to its widespread presence. Traditional micro-imaging measurement of microplastics often rely on post-cruise laboratory analyses. In this study, we explored the feasibility of onboard microplastic measurement using Raman spectroscopy, with a focus on polyethylene (PE).

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Sea urchins, integral to marine ecosystems and valued as a delicacy in Asia and Europe, contain physiologically important long-chain (>C) polyunsaturated fatty acids (PUFA) in their gonads, including arachidonic acid (ARA, 20:4n-6), eicosapentaenoic acid (EPA, 20:5n-3) and unusual non-methylene-interrupted fatty acids (NMI-FA) such as 20:2. Although these fatty acids may partially be derived from their diet, such as macroalgae, the present study on has uncovered multiple genes encoding enzymes involved in long-chain PUFA biosynthesis. Specifically, 3 fatty acid desaturases (FadsA, FadsC1 and FadsC2) and 13 elongation of very-long-chain fatty acids proteins (Elovl-like, Elovl1/7-like, Elovl2/5-like, Elovl4-like, Elovl8-like and Elovl6-like A-H) were identified in their genome and transcriptomes.

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Auxiliary metabolic genes encoded by bacteriophages can influence host metabolic function during infection. In temperate phages, auxiliary metabolic genes may increase host fitness when integrated as prophages into the host genome. However, little is known about the contribution of prophage-encoded auxiliary metabolic genes to host metabolic properties.

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sp. nov., a crude oil aggregation-forming anaerobic bacterium isolated from marine sediment.

Int J Syst Evol Microbiol

January 2025

Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato, Tokyo 108-8477, Japan.

A crude oil aggregation-forming, strictly anaerobic, Gram-stain-positive, spore-forming, rod-shaped, motile and mesophilic bacterium, named strain SH18-2, was isolated from marine sediment near Sado Island in the Sea of Japan. The temperature, salinity and pH ranges of this strain for the growth were 15-40 °C (optimum 35 °C), 0.5-6.

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Recent rapid sea ice reduction in the Pacific sector of the Arctic Ocean is potentially associated with inflow of Pacific-origin water via the Bering Strait. For the first time, we detected remarkable subsurface warming around the Chukchi Borderland in the Arctic Ocean over the recent two decades (i.e.

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The characteristics and prospective applications of North Pacific krill chitin and chitosan are currently unexplored, and their conventional isolation method is time- and energy-consuming. In this study, chitin and chitosan were extracted from North Pacific krill using conventional and microwave-assisted methods, followed by comprehensive characterisation and evaluation of chitosan film potential. The extracted chitin was identified as an α-polymorph, and chitosan exhibited a remarkable degree of deacetylation (90 %) in both methods.

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Influence of mesh selectivity on risk assessment of marine microplastics.

Mar Pollut Bull

January 2025

Department of Ocean Sciences, Tokyo University of Marine Science and Technology, Konan 4-5-7, Minato-Ku, Tokyo 108-8477, Japan. Electronic address:

In this study, environmental microplastic samples (>30 μm) were collected from surface seawater and the water column, characterized, and used to assess ecological risks. The influence of mesh selectivity on ecological risks was also evaluated through subsampling. Results show that surface microplastic concentrations (>30 μm) range from 92 to 3306 pieces/m along Japan's southwest coast, with significant increases at Stas.

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The brown alga (SF) is historically consumed as a food material in Japan. A steaming process is often required for SF products on the market due to their moderate hardness and astringent taste. This investigation aimed to elucidate the effect of steaming on the anti-diabetic activity of SF and its related chemical components.

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Identification of two novel α-amylase inhibitory activity peptide from Russian sea cucumber body wallprotein hydrolysate.

Int J Biol Macromol

January 2025

State Key Laboratory of Food Nutrition and Safety, Engineering Research Center of Food Biotechnology, Ministry of Education, Tianjin University of Science & Technology, Tianjin 300457, China. Electronic address:

This study aimed to identify novel α-amylase inhibitory peptides from Russian sea cucumbers and elucidate their inhibitory mechanisms. Among the 52 identified sea cucumber peptide (SCP), two peptides with potential α-amylase inhibitory activity, FPSPPLVA (SCP1) and GPPMPPPPLP (SCP2), were selected from the sequences researched. The results showed that both SCP1 and SCP2 exhibited α-amylase inhibitory activity with IC of 0.

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Helicobacter pylori-Related Chronic Gastritis as a Risk Factor for Lower Bone Mineral Density.

Calcif Tissue Int

January 2025

Department of Gastroenterology, School of Medicine, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama, 641-0012, Japan.

We evaluated the role of Helicobacter pylori (H. pylori)-related chronic gastritis in the development of osteoporosis in a population-based study. A total of 1690 subjects in the cohort of the Research on Osteoarthritis/ osteoporosis Against Disability (ROAD) were investigated, and the association between gastritis and osteoporosis was evaluated by the presence of serologically assessed H.

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A microfluidics platform for simultaneous evaluation of sensitivity and side effects of anti-cancer drugs using a three-dimensional culture method.

Sci Rep

January 2025

Laboratory of Veterinary Pharmacology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu , Tokyo, 183-8509, Japan.

Organoids are stem cell-derived three-dimensional tissue cultures composed of multiple cell types that recapitulate the morphology and functions of their in vivo counterparts. Organ-on-a-chip devices are tiny chips with interconnected wells and channels designed using a perfusion system and microfluidics to precisely mimic the in vivo physiology and mechanical forces experienced by cells in the body. These techniques have recently been used to reproduce the structure and function of organs in vitro and are expected to be promising alternatives for animal experiments in the future.

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In recent years, in vitro skin sensitization assays have been recommended as animal-free alternatives for the safety assessment of cosmetics and topical drugs, and these methods have been adopted in OECD test guidelines. However, existing assays remain complex and costly. To address this, we recently developed a more efficient, cost-effective, and accurate method for evaluating skin sensitizers by using immune cell-derived THP-1 cells as a biosensor, coupled with an RT-PCR-based assay.

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Plastic pollution and marine mussels: Unravelling disparities in research efforts, biological effects and influences of global warming.

Sci Total Environ

January 2025

Université de Lille, CNRS, Université du Littoral Côte d'Opale, IRD, UMR 8187, LOG, Laboratoire d'Océanologie et de Géosciences, Station marine de Wimereux, F-59000 Lille, France; Department of Marine Resources and Energy, Tokyo University of Marine Science and Technology, 4-5-7 Konan, Minato-ku, Tokyo 108-8477, Japan; Department of Zoology and Entomology, Rhodes University, Grahamstown 6140, South Africa.

The ever-growing contamination of the environment by plastics is a major scientific and societal concern. Specifically, the study of microplastics (1 μm to 5 mm), nanoplastics (< 1 μm), and their leachates is a critical research area as they have the potential to cause detrimental effects, especially when they impact key ecological species. Marine mussels, as ecosystem engineers and filter feeders, are particularly vulnerable to this type of pollution.

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The Gram-negative bacterium is a serious shrimp pathogen. Here, we present the genome sequence of TUMSAT-2019, which was isolated from a kuruma shrimp () that originated from a shrimp farm in Okinawa Prefecture. The assembly totaled 5.

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Article Synopsis
  • Harmful algal blooms (HABs), especially those from toxin-producing microalgae like Prorocentrum micans, are a recurring issue in Patagonian fjords, and a significant HB-HAB occurred in Northwest Chilean Patagonia during February-March 2022.
  • Observations showed a dramatic increase in P. micans cell density from low levels in January to a peak of over 8.3 x 10 cells/mL by mid-February, associated with warmer sea temperatures and varying salinity.
  • Satellite images and oceanographic modeling revealed that water currents and temperature variations in the Gulf of Ancud supported the development and maintenance of this harmful algal bloom, indicating a hotspot for both HABs and HB-HAB
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The lack of a classical adaptive immunity renders the development of disease control and prevention measures in shrimp challenging. In this study, the concept of trained immunity was exploited in the development of a feed supplement. Penaeus vannamei shrimp was fed with feed supplemented with freeze-dried whole culture of Lactiplantibacillus plantarum (FD-LAB) for 15 days.

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The pejerrey (Odontesthes bonariensis) is a key species for recreational and commercial fisheries in Argentina and holds significant aquaculture potential. It has been introduced to various countries worldwide, including Japan, where intensive aquaculture has developed. However, infectious diseases present major challenges to its cultivation, as pejerrey is susceptible to diverse pathogens, including bacteria, fungi and parasites.

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Background: Shrimp gill health is an indicator of their overall health and environmental stress, as gills are in direct contact with the external environment. Organic selenium (OS), known for its high bioavailability and antioxidant properties, potentially enhances shrimp growth, survival, and immune responses. This study investigated the physiological features through comprehensive gill gene expression profiling and growth parameters by incorporating OS into Penaeus vannamei diets.

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During a survey of the shallow water decapod fauna in the Miura Peninsula, Kanagawa Prefecture, central Japan, four specimens of a new palaemonid shrimp, Palaemon parvibrachium n. sp., were collected from sea grass beds of Nanozostera japonica (Ascherson & Graebner) Tomlinson & Posluszny, 2001.

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We investigated the carbonyl index (CI) of small microplastics (SMPs; 50-350 μm) and large microplastics (LMPs; >350 μm) in the surface waters of the Tokai region and Tokyo Bay in Japan. The degradation was evaluated by determining the CI from the infrared spectrum of microplastics (MPs) adopting the specified area under the band technique. Average CIs of SMPs and LMPs in polyethylene were 2.

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Cell lines derived from fish tissues are resistant to premature senescence under typical culture conditions. Previously, we demonstrated that fish genomes do not have a p16/Arf locus and that the absence of this locus underlies the lack of senescence in cultured fish cells. However, other factors may also contribute to this resistance.

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Aquatic microplastics research in the ASEAN region: Analysis of challenges and priorities.

Mar Pollut Bull

January 2025

Research Institute for Applied Mechanics, Kyushu University, Kasuga, Japan; Center for Ocean Plastic Studies, Kyushu University, CU Research Building, Bangkok, Thailand.

Research on microplastics must be harmonized. Therefore, we thoroughly evaluated in the Association of Southeast Asian Nations (ASEAN) region, addressing challenges and priorities in protocol harmonization and microplastics research promotion. Of the 615 papers searched by the Web of Science, 164 were used for this systematic review.

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Article Synopsis
  • The COVID-19 pandemic caused significant disruptions in healthcare use in Japan, especially during its later stages (2022-2023), which had not been thoroughly studied before.
  • A quasi-Poisson regression model was used to analyze trends in inpatient and outpatient healthcare utilization in Japan, revealing that inpatient volumes remained consistently lower than pre-pandemic levels and that psychiatric care saw a decline in occupancy rates.
  • The findings indicate that the pandemic has led to lasting changes in healthcare patterns, with reduced inpatient volumes and prolonged psychiatric hospital stays, highlighting the need for ongoing monitoring of healthcare services.
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White spot syndrome virus (WSSV) poses a significant threat to shrimp aquaculture, leading to substantial economic losses. This study aims to evaluate the virulence and evolution of recent WSSV outbreaks in Japan. Shrimp infected with WSSV were collected from Okinawa, Miyakojima and Miyazaki prefectures, yielding a total of seven isolates.

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