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51.
Yuko Miyajima-Taga Reiji Masuda Yoh Yamashita 《Environmental Biology of Fishes》2017,100(10):1237-1249
Although many fish species are known to feed on jellyfish, only a few quantitative studies on this subject have been conducted in the field or laboratory. We combined field observations and feeding experiments to quantitatively evaluate the potential feeding capability of the black scraper Thamnaconus modestus on giant jellyfish Nemopilema nomurai in a jellyfish-abundant area. Underwater observations revealed that shoals of T. modestus fed voraciously on jellyfish when the jellyfish were close to the fish’s seaweed habitat. Gut contents of field-collected T. modestus almost exclusively consisted of jellyfish. In tank trials, feeding activity of black scraper was high when light intensity was between about 1.1 lx and 50 × 103 lx. The estimated feeding speed of T. modestus on the jellyfish in the Sea of Japan when the jellyfish bloom occurred was 10.0 ± 2.0 times fish body weight per day. The results support the prediction that T. modestus and probably other coastal medusivorous fishes have a substantial capability to eliminate jellyfish blooms. Considering that they are highly dependent on seaweed bed, protection of such habitats for these medusivores may be the most cost-efficient control method for jellyfish blooms. 相似文献
52.
We describe a case of inflammatory myofibroblastic tumor (IMT) that occurred in the retroperitoneum. The patient manifested systemic symptoms, such as intermittent fever, anemia, thrombocytosis, and hypergammaglobulinemia. In order to elucidate the mechanism of intermittent fever in IMT, we analyzed nuclear factor-kappa B (NF-kappaB) activation in peripheral blood mononuclear cells (PBMCs) using flow cytometry, and serum cytokine levels. NF-kappaB activation was observed in the peripheral blood T cells and monocytes/macrophages. Among the measured cytokines, only interleukin (IL)-6 levels were elevated. IL-6 levels during pyrexia in the afternoon were higher than those during apyrexia in the morning. In contrast to IL-6, NF-kappaB activation in PBMCs was lower during pyrexia than during apyrexia; this is considered to be because the activation is subject to negative feedback. The time lag between the increase of IL-6 in the serum and NF-kappaB activation in the PBMCs at the onset of intermittent fever in IMT may provide further insight into the role of cytokines and NF-kappaB activation in febrile inflammatory diseases. 相似文献
53.
Seasonal and interannual variation of subtidal fish assemblages in Wakasa Bay with reference to the warming trend in the Sea of Japan 总被引:1,自引:0,他引:1
Reiji Masuda 《Environmental Biology of Fishes》2008,82(4):387-399
A bi-monthly underwater visual census was conducted in the subtidal habitat of Nagahama, Wakasa Bay, Sea of Japan, over 5 years
from January 2002 to December 2006. A total of 83 fish species and 63,328 individuals were recorded over 120 1-h visual censuses
composed of three 2 × 200 m transects. The number of both total individuals (abundance) and species (richness) were strongly
correlated with the bottom-water temperature. Species richness was greatest in summer (July–September), with 10–20 species
per 400 m2, when the sea-bottom temperature was highest (24–28°C), and lowest in winter (January–March), with 1–8 species per 400 m2, when the temperature was lowest (10–12°C). Five species, i.e., rockfish, Sebastes inermis, wrasse, Pseudolabrus sieboldi, two species of goby, Acentrogobius pflaumii and Tridentiger trigonocephalus, and pygmy filefish, Rudarius ercodes, were frequently observed and present in more than 200 of the total of 360 total transects. While the presence of most fish
species was dependent on water temperature, some species were independent of water temperature, including anchovy, Engraulis japonicus, S. inermis, wasp fish, Hypodytes rubripinnis, A. pflaumii and pufferfish, Takifugu poecilonotus. Jack mackerel, Trachurus japonicus, was the most abundant fish, being most typically seen from spring through autumn, with a total of 21,850 individuals observed
over the whole census period. Some species showed strong annual fluctuations in abundance. The interannual stability in fish
abundance and species richness was probably because the fish assemblage was composed of a sufficiently large number of species,
but with the number of each species fluctuating over time. A comparison of the present survey to one in 1970–72 revealed that
over the last 30 years southern fish species have significantly increased whereas those indigenous to northern waters have
decreased.
相似文献
Reiji MasudaEmail: |
54.
Several sulfated sialoglycoconjugates have recently been shown to serve as ligands for selectins and siglecs. For instance, α2→3 sialylated 6-sulfo-Lewis x was found to serve as a ligand for selectins on skin-homing helper memory T cells, and α2→6 sialylated 6-sulfo-LacNAc to be a preferred ligand for CD22/siglec-2 on human naïve B cells. Monoclonal antibodies specific to sulfated sialoglycoconjugates are effective tools to dissect these ligands on minor subsets of human leukocytes. 相似文献
55.
Anthropogenic addition of reactive nitrogen (Nr) to the biosphere is increasing globally and some terrestrial ecosystems are
suffering from a state of excess Nr for biological nitrogen (N) demand, termed N saturation. Here, we review the ecological
risks in relation to N saturation and prospective responses to N saturation. Excess Nr increases the risks of local extinction
of rare plant species, encouragement of exotic plant species, disturbance of nutrient balance in plant organs, and increase
of herbivory in plant communities. On the ecosystem scale, excess bioavailable N induces forest decline, disturbance of nutrient
cycling within ecosystems, depending on vegetation, soil, land-use, and N-loading history. These Nr risks will increase in
the Asian region, where impacts of Nr in natural terrestrial ecosystems have been scarcely studied. Whether much of the terrestrial
ecosystems on a global level are in the sate of N saturation or not is still controversial, but the potential risks of excess
Nr seem to be increasing. The fundamental ways to mitigate Nr risks are to reduce Nr production, prevent Nr translocation,
and promote conversion of Nr to N2. Temporal, but promising actions against ecological N risks may include management of forests and riparian zones, and carbon
addition in grassland. 相似文献
56.
Kyogashima M Tamiya-Koizumi K Ehara T Li G Hu R Hara A Aoyama T Kannagi R 《Glycobiology》2006,16(8):719-728
By combining the partition method for enrichment of sulfatides without any chromatographic procedures and the preparation method of lysosulfatides, we succeeded in analyzing these sulfated glycosphingolipids from biological materials by matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) to reduce the complexity of mass fragmentation patterns within a day. We found that sulfated GalCer (HSO3-3Gal beta 1Cer) (SM4s [galactosylsulfatide]) was composed of different species. While composition of SM4s specifically depended on source materials, it always contained hydroxy fatty acids of various degrees. In addition to the common sphingoid 4-sphingenine (d18:1), uncommon/unusual sphingoids phytosphingosine (4-hydroxysphinganine) (t18:0), eicosasphinganine (d20:0), 4-eicosasphingenine (d20:1), and sphingadienine (d18:2) were easily detected. Finally, in addition to SM4s, sulfatide sulfated LacCer (HSO3-3Gal beta 4Glc beta 1Cer) (SM3 [sulfated lactosylceramide]) and sulfated Gg3Cer (GalNAc beta 4(HSO3-3)Gal beta 4Glc beta 1Cer) (SM2 [sulfated gangliotriaosylceramide]) were clearly detected in renal tubule cells. The major SM4s was composed of ceramides possessing d18:1 with C22 hydroxy fatty acids (C22:0 h), C23:0 h, and C24:0 h, whereas the major SM3/SM2 were composed of ceramides possessing t18:0 with C22 normal fatty acids (C22:0), C23:0, C24:0. Namely, in these two series of sulfatides, either fatty acids or sphingoids were hydroxylated, and chain lengths of these components were exactly the same, consequently resulting in a similar polarity of ceramide moieties in these sulfatide species. These results demonstrated diversities of sulfatide molecular species, not only with respect to sugar moieties but also to ceramide moieties, which are probably important for specific effective functions in particular microenvironments such as lipid membrane microdomains. 相似文献
57.
Saito S Kobayashi M Kimoto-Nira H Aoki R Mizumachi K Miyata S Yamamoto K Kitagawa Y Suzuki C 《FEMS microbiology letters》2011,316(1):70-76
Lactobacillus paraplantarum is a species phenotypically close to Lactobacillus plantarum. Several PCR methods were evaluated to discriminate L. paraplantarum strains and among them, a PCR using an enterobacterial repetitive intergenic consensus (ERIC) sequence differentiated L. paraplantarum from other Lactobacillus species. In addition, a combination of ERIC and random amplified polymorphic DNA (RAPD) analysis distinguished among seven strains of L. paraplantarum tested. ERIC-PCR profiles showed several strain-specific DNA fragments in L. paraplantarum, among them, a 2.2-kb ERIC marker, termed LpF1, found to be specific to strain FBA1, which improved the skin integrity in an animal model. The LpF1 encodes three proteins similar to Lactobacillus fermentum AroA, TyrA, and AroK, which are involved in the shikimate pathway. A primer pair specific to FBA1 based on the internal sequence of LpF1 amplified a 950-bp FBA1-specific fragment LpF2. Southern blot analysis of Dra I-digested genomic DNA of L. paraplantarum strains using LpF2 as a probe showed that LpF2 is distinctive of strain FBA1 among 16 L. paraplantarum strains. Because both ERIC- and RAPD-PCR are fast and technically simple methods, they are useful for the rapid discrimination of L. paraplantarum strains and for the development of new strain-specific DNA markers for identifying industrially important strains. 相似文献
58.
Tanaka K Yamada M Tamiya-Koizumi K Kannagi R Aoyama T Hara A Kyogashima M 《Glycoconjugate journal》2011,28(2):67-87
Free ceramides and glycosphingolipids (GSLs) are important components of the membrane microdomain and play significant roles
in cell survival. Recent studies have revealed that both fatty acids and long-chain bases (LCBs) are more diverse than expected,
in terms of i) alkyl chain length, ii) hydroxylation and iii) the presence or absence of double bonds. Electrospray ionization
mass spectrometry and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) have been
well utilized to characterize sphingolipids with high throughput, but reports to date have not fully characterized various
types of ceramide species such as hydroxyl fatty acids and/or trihydroxy-LCBs of both free ceramides and the constituent ceramides
in neutral GSLs. We performed a systematic analysis of both ceramide species, including LCBs with nona-octadeca lengths using
MALDI-TOF MS with high-energy collision-induced dissociation (CID) at 20 keV. Using both protonated and sodiated ions, this
technique enabled us to propose general rules to discriminate between isomeric and isobaric ceramide species, unrelated to
the presence or absence of sugar chains. In addition, this high-energy CID generated 3,5A ions, indicating Hex1-4Hex linkage in the sugar chains. Using this method, we demonstrated distinct differences among ceramide
species, including free ceramides, sphingomyelins, and neutral GSLs of glucosylceramides, galactosylceramides, lactosylceramides,
globotriaosylceramides and Forssman glycolipids in the equine kidneys. 相似文献
59.
Ito M Okui H Nakagawa H Mio S Kinoshita A Obayashi T Miura T Nagai J Yokoi S Ichinose R Tanaka K Kodama S Iwasaki T Miyake T Takashio M Iwabuchi J 《Bioorganic & medicinal chemistry》2003,11(5):761-768
This paper reports the synthesis and insecticidal activity of a series of novel 4-hydroxy-3-mesityl-1-methoxymethoxy-1,5-dihydro-2H-pyrrol-2-one derivatives, in which the substituents at the 5-position were varied with a number of alkyl and spirocycloalkyl groups. Investigation of the structure-activity relationships revealed that small alkyl and spirocyclohexyl groups had a favorable effect on the insecticidal activity of these agents against Myzus persicae. 相似文献
60.
Reiji Kojima Tatsukuni Ohno Motoyasu Iikura Toshiro Niki Mitsuomi Hirashima Keichi Iwaya Hitoshi Tsuda Shigeaki Nonoyama Akio Matsuda Hirohisa Saito Kenji Matsumoto Susumu Nakae 《PloS one》2014,9(1)
Galectin-9 (Gal-9), a lectin having a β-galactoside-binding domain, can induce apoptosis of Th1 cells by binding to TIM-3. In addition, Gal-9 inhibits IgE/Ag-mediated degranulation of mast cell/basophilic cell lines by binding to IgE, thus blocking IgE/Ag complex formation. However, the role of Gal-9 in mast cell function in the absence of IgE is not fully understood. Here, we found that recombinant Gal-9 directly induced phosphorylation of Erk1/2 but not p38 MAPK in a human mast cell line, HMC-1, which does not express FcεRI. Gal-9 induced apoptosis and inhibited PMA/ionomycin-mediated degranulation of HMC-1 cells. On the other hand, Gal-9 induced cytokine and/or chemokine production by HMC-1 cells, dependent on activation of ERK1/2 but not p38 MAPK. In addition, the lectin activity of Gal-9 was required for Gal-9-mediated cytokine secretion by HMC-1 cells. These observations suggest that Gal-9 has dual properties as both a regulator and an activator of mast cells. 相似文献