Predation risk management of sea stars (Asterias amurensis and Distolasterias nipon) by adjusting the density and size of seeded scallops (Mizuhopecten yessoensis): an improvement to local mariculture     

Miyoshi  Koji  Chiba  Susumu 《Aquaculture International》2022,30(1):429-443

Optimizing the release density and size of juvenile commercial species for local ecosystems is a critical issue that should be considered when countering predation impacts. To ascertain whether mariculture production of the Japanese scallop (Mizuhopecten yessoensis) could be enhanced by modifying releasing practices, we experimentally investigated the effects of density and size of scallop seeds on their survival in the presence of two sea star species, Asterias amurensis and Distolasterias nipon, with different predation capacities. Under current mariculture practices, the juveniles are briefly exposed to air just before release; therefore, we also examined how air exposure stress increased the predation risk. Scallop survival in the presence of both sea stars increased by?>?20% by increasing scallop size from 30 to 50 mm. Increasing scallop density (range: 5 to 30 scallops m^?2) increased each individual’s survival in the presence of A. amurensis but had no significant effect on predation by D. nipon. Therefore, the release of smaller quantities of large-sized scallops rather than larger quantities of small scallops is recommended to reduce D. nipon predation. In the presence of sea stars, especially by D. nipon, the predation impact on small scallops increased after just a few hours of air exposure, indicating that air exposure of juvenile scallops should be minimized. Our results will mitigate the economic cost of mariculture by facilitating the determination of optimal release conditions for juvenile scallops.

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Whole-genome resequencing using genomic DNA extracted from horsehair roots for gene-doping control in horse sports     

Teruaki TOZAKI  Aoi OHNUMA  Mio KIKUCHI  Taichiro ISHIGE  Hironaga KAKOI  Kei-ichi HIROTA  Natasha A. HAMILTON  Kanichi KUSANO  Shun-ichi NAGATA 《Journal of Equine Science》2020,31(4):75

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Transcriptome analysis of the duodenum in Wistar rats fed a trypsin inhibitor derived from squid viscera     

Adachi K  Fukumorita K  Araki M  Zaima N  Chiba S  Kishimura H  Saeki H 《Journal of agricultural and food chemistry》2011,59(16):9001-9010

To investigate the effects of oral administration of a trypsin inhibitor (TI), normal Wistar rats were fed a TI derived from squid (Todarodes pacificus) for 10 weeks and gene expression profiles in the duodenum, pancreas, liver, and muscle were then analyzed using DNA microarrays. Although no significant changes could be observed in growth, food intake, tissue weight, or blood tests among the tissues tested, the duodenum showed the most remarkable changes in the global gene expression profile. Significant up-regulation of mRNAs encoding gastrin, gastrokine, cholecystokinin and somatostatin in the duodenum was validated by qPCR analysis. In gene ontology (GO) analysis of the up-regulated differentially expressed genes (DEGs), GO terms related to keratinization and innate mucosal defense were enriched (p < 0.001) in the category of biological processes in addition to assumable terms such as regulation of secretion and response to nutrients, vesicle-mediated transport, and so forth. In the same analysis, calcium ion binding was listed at the deepest hierarchy in the category of molecular function. These results indicate that the duodenum responds to TI treatment by a wider range of physiological processes than previously assumed such as keratinocyte differentiation and innate mucosal defense, in which calcium plays a crucial role.  相似文献   

Epizootiological study of tick-borne encephalitis virus infection in Japan     

Yoshii K  Mottate K  Omori-Urabe Y  Chiba Y  Seto T  Sanada T  Maeda J  Obara M  Ando S  Ito N  Sugiyama M  Sato H  Fukushima H  Kariwa H  Takashima I 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(3):409-412

Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis in humans. Rodent species that are potential hosts for TBEV are widely distributed in various regions in Japan. In this study, we carried out large-scale epizootiological surveys in rodents from various areas of Japan. A total of 931 rodent and insectivore sera were collected from field surveys. Rodents seropositive for TBEV were found in Shimane Prefecture in Honshu and in several areas of Hokkaido Prefecture. These results emphasize the need for further epizootiological and epidemiological research of TBEV and preventive measures for emerging tick-borne encephalitis in Japan.  相似文献   

Immunobiotic lactic acid bacteria beneficially regulate immune response triggered by poly(I:C) in porcine intestinal epithelial cells     

Hosoya S  Villena J  Shimazu T  Tohno M  Fujie H  Chiba E  Shimosato T  Aso H  Suda Y  Kawai Y  Saito T  Alvarez S  Ikegami S  Itoh H  Kitazawa H 《Veterinary research》2011,42(1):111

ABSTRACT: This study analyzed the functional expression of TLR3 in various gastrointestinal tissues from adult swine and shows that TLR3 is expressed preferentially in intestinal epithelial cells (IEC), CD172a+CD11R1high and CD4+ cells from ileal Peyer's patches. We characterized the inflammatory immune response triggered by TLR3 activation in a clonal porcine intestinal epitheliocyte cell line (PIE cells) and in PIE-immune cell co-cultures, and demonstrated that these systems are valuable tools to study in vitro the immune response triggered by TLR3 on IEC and the interaction between IEC and immune cells. In addition, we selected an immunobiotic lactic acid bacteria strain, Lactobacillus casei MEP221106, able to beneficially regulate the anti-viral immune response triggered by poly(I:C) stimulation in PIE cells. Moreover, we deepened our understanding of the possible mechanisms of immunobiotic action by demonstrating that L. casei MEP221106 modulates the interaction between IEC and immune cells during the generation of a TLR3-mediated immune response.  相似文献   

Boophilus microplus cathepsin L-like (BmCL1) cysteine protease: specificity study using a peptide phage display library     

Clara RO  Soares TS  Torquato RJ  Lima CA  Watanabe RO  Barros NM  Carmona AK  Masuda A  Vaz IS  Tanaka AS 《Veterinary parasitology》2011,181(2-4):291-300

The tick Rhipicephalus (Boophilus) microplus is one of the most important bovine ectoparasites, a disease vector responsible for losses in meat and milk productions. A cysteine protease similar to cathepsin L, named BmCL1, was previously identified in R. microplus gut, suggesting a role of the enzyme in meal digestion. In this work, BmCL1 was successfully expressed in Pichia pastoris system, yielding 54.8 mg/L of culture and its activity was analyzed by synthetic substrates and against a R. microplus cysteine protease inhibitor, Bmcystatin. After rBmCl1 biochemical characterization it was used in a selection of a peptide phage library to determine rBmCL1 substrate preference. Obtained sequenced clones showed that rBmCL1 has preference for Leu or Arg at P(1) position. The preference for Leu at position P(1) and the activation of BmCL1 after a Leu amino acid residue suggest possible self activation.  相似文献   

Generation of pluripotent stem cells from adult mouse liver and stomach cells   总被引：1，自引：0，他引：1  

Aoi T  Yae K  Nakagawa M  Ichisaka T  Okita K  Takahashi K  Chiba T  Yamanaka S 《Science (New York, N.Y.)》2008,321(5889):699-702

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Comparison of the effects of chemical anesthesia and electroanesthesia on plasma cortisol levels in the Japanese eel Anguilla japonica     

Hiroaki Chiba  Tadamichi Hattori  Hideaki Yamada  Munehico Iwata 《Fisheries Science》2006,72(3):693-695

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Ontogenetic changes of alpha-melanocyte-stimulating hormone (α-MSH)-like immunoreactivity in the brain and hypophysis of a scyliorhinid dogfish (Scyliorhinus torazame): An immunohistochemical study     

A. Chiba  S. Oka 《Fish physiology and biochemistry》2001,25(2):165-170

Ontogenetic development of α-MSH-IR (alpha-melanocyte-stimulating hormone-like immunoreactivity) in the brain and hypophysis of a scyliorhinid dogfish (Scyliorhinus torazame) was studied immunohistochemically. α-MSH-IR first appeared in the hypothalamus of the brain in embryos at the 43-mm stage. Thereafter, α-MSH-positive cells and fibers gradually increased in number in mainly the tuberculum posterius of the hypothalamus during the embyonic periods. In the post-hatching juveniles at the 95-mm and 125-mm stages, α-MSH-positive structures in the brain were comparable to those in adult fish, although the distributional range of α-MSH-IR structures in the brain was less extensive than those in adult fish. In the hypophysis, α-MSH-positive cells first appeared in the caudal part of the adenohypophysis at the 54-mm stage, approximately coincident with the onset of pigmentation in the skin. During ontogenesis, the MSH-producing cells increased in number straightforwardly in the adenohypophysis. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Horizontal and vertical variations in photosynthetic capacity in a Pinus densiflora crown in relation to leaf nitrogen allocation and acclimation to irradiance     

Han Q  Kawasaki T  Katahata S  Mukai Y  Chiba Y 《Tree physiology》2003,23(12):851-857

We measured horizontal and vertical gradients of light (rPPFD) along four first-order branches of a Pinus densiflora Sieb. & Zucc. crown, and compared variations in specific leaf area (SLA), needle nitrogen concentration (N), chlorophyll concentration (Chl) and photosynthetic capacity (i.e., maximum rate of carboxylation (V(cmax))) along the two axes. The horizontal gradient of rPPFD along first-order branches was similar in magnitude to the vertical gradient of rPPFD from the upper to the lower crown. None of the measured parameters (i.e., SLA, N, Chl and Vcmax) were strictly proportional to rPPFD, although they were more or less correlated with light when data obtained for all of the crown were pooled (r(2) = 0.31-0.80). The slope of rPPFD against N on an area basis (Narea) for a branch in the middle of the crown orientated northward was significantly greater than the slope for a similar branch orientated southward. Horizontal variations were unrelated to age effects because measurements were all on 1-year-old needles. We conclude that factors other than light (i.e., orientation) may influence N allocation within branches. There was considerably less variation in the relationship of Vcmax to Narea (r2 = 0.58) than in the relationship of Vcmax to rPPFD (r2 = 0.41). Fractional N distribution among components of the photosynthetic machinery was constant within the crown. Together with the relationships between rPPFD and N on a mass basis (r2 = 0.80) and SLA and Vcmax (r2 = 0.60), these findings suggest that most light acclimation in P. densiflora occurs through changes in needle morphology (e.g., SLA) during development.  相似文献