Environmental DNA (eDNA) is a promising tool for the continuous monitoring of fish ecology and diversity. However, its potential for describing the phenological activity of fish has rarely been examined. This study aimed to elucidate a linkage between the spatiotemporal distribution of eDNA and the phenology of an amphidromous fish, ayu Plecoglossus altivelis altivelis, in a river in Hokkaido, Japan, which is its northernmost distributional area.
View Article and Find Full Text PDFClarifying the effect of the sampling protocol on the detection of environmental DNA (eDNA) is essential for appropriately designing biodiversity research. However, technical issues influencing eDNA detection in the open ocean, which consists of water masses with varying environmental conditions, have not been thoroughly investigated. This study evaluated the sampling effort for the metabarcoding-based detection of fish eDNA using replicate sampling with filters of different pore sizes (0.
View Article and Find Full Text PDFSeven South Pacific anguillid eel species live from New Guinea to French Polynesia, but their spawning areas and life histories are mostly unknown despite previous sampling surveys. A July-October 2016 research cruise was conducted to study the spawning areas and times, and larval distributions of South Pacific anguillid eels, which included a short 155°E station-line northeast of New Guinea and five long transects (5-25°S, 160°E-140°W) crossing the South Equatorial (SEC) and other currents. This survey collected nearly 4000 anguilliform leptocephali at 179 stations using an Isaacs-Kidd Midwater Trawl accompanied by 104 CTD casts.
View Article and Find Full Text PDFBifidobacterium, one of the major components of intestinal microflora, shows anti-influenza virus (IFV) potential as a probiotic, partly through enhancement of innate immunity by modulation of the intestinal immune system. Bifidobacterium longum MM-2 (MM-2), a very safe bacterium in humans, was isolated from healthy humans and its protective effect against IFV infection in a murine model shown. In mice that were intranasally inoculated with IFV, oral administration of MM-2 for 17 consecutive days improved clinical symptoms, reduced mortality, suppressed inflammation in the lower respiratory tract, and decreased virus titers, cell death, and pro-inflammatory cytokines such as IL-6 and TNF-α in bronchoalveolar lavage fluid.
View Article and Find Full Text PDFInfluenza A virus (IAV) recognizes two types of N-acetylneuraminic acid (Neu5Ac) by galactose (Gal) linkages, Neu5Acα2,3Gal and Neu5Acα2,6Gal. Avian IAV preferentially binds to Neu5Acα2,3Gal linkage, while human IAV preferentially binds to Neu5Acα2,6Gal linkage, as a virus receptor. Shift in receptor binding specificity of avian IAV from Neu5Acα2,3Gal linkage to Neu5Acα2,6Gal linkage is generally believed to be a critical factor for its transmission ability among humans.
View Article and Find Full Text PDFInfluenza A virus (IAV) generally causes caspase-dependent apoptosis based on caspase-3 activation, resulting in nuclear export of newly synthesized viral nucleoprotein (NP) and elevated virus replication. Sulfatide, a sulfated galactosylsphingolipid, enhances IAV replication through promoting newly synthesized viral NP export induced by association of sulfatide with hemagglutinin delivered to the cell surface. Here, we demonstrated that sulfatide is involved in caspase-3-independent apoptosis initiated by the PB1-F2 protein of IAV by using genetically sulfatide-produced cells and PB1-F2-deficient IAVs.
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