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991.
To ascertain the feeding habits of benthic juvenile yellowfin goby Acanthogobius flavimanus, the gut contents of 599 specimens (15–41 mm in standard length, SL), collected on a tidal mudflat in the Tama River estuary
throughout the diel cycle, were examined. The major prey items changed from harpacticoid copepods to errant and sedentary
polychaetes at ca. 20 mm SL. Prey width increased with fish size. Fish of 26–28 mm SL fed mainly from sunset to morning, with
highest feeding intensity during twilight hours and/or high tide. Based on the gut evacuation rate estimated from a forced
feeding experiment in the laboratory and data for the diel change of mean gut-content volume in the field, the daily ration
of juvenile yellowfin goby (26–28 mm SL) was calculated to be 13.8 mm3 fish−1 day−1. This volume is approximately equivalent to 3.9 individuals of the errant polychaete Ceratonereis erythraeensis (9.7 mm in body length, BL) or 8.1 individuals of the sedentary polychaete Prionospio japonica (14.8 mm BL), both species occurring abundantly on the mudflat during the study. 相似文献
992.
Root respiration rate before and just after clear-felling in a mature,deciduous, broad-leaved forest 总被引:12,自引:0,他引:12
Soil respiration was measured throughout the year (June 1992 to May 1993) in a mature, deciduous, broad-leaved forest and
an adjacent, clear-felled stand which was made in November 1991, in Hiroshima Prefecture, west Japan. The same soil temperature
and soil moisture content as those in the forest stand were maintained in two frame boxes covered with sheets of white netting
in the clear-felled stand to observe soil respiration. A herbicide was applied to the cut end of all stumps in one of the
two frame boxes in order to kill the root system. There was no significant difference in the aboveground biomass and soil
environmental conditions between the forest and the frame boxes in the clear-felled stands. The difference in soil respiration
rate between the forest and the frame box, in which the root system was killed by the herbicide, was considered to be due
largely to the contribution of root respiration. Taking into consideration CO2 evolution due to the decomposition of roots killed and the change in A0 layer respiration rate after clear-felling, the proportion of root respiration to the total soil respiration before clear-felling
was estimated to be 51% annually, which coincides closely with those values estimated previously in mature forests by other
methods. The difference in the soil respiration rate between the two frame boxes (one with killed roots and the other with
undisturbed roots) suggested that the annual root respiration rate just after clear-felling dropped to about two-thirds (70%)
of that before clear-felling. 相似文献
993.
Koji Ueda Sachiko Takami Naomi Saichi Yataro Daigo Nobuhisa Ishikawa Nobuoki Kohno Masaru Katsumata Akio Yamane Minoru Ota Taka-Aki Sato Yusuke Nakamura Hidewaki Nakagawa 《Molecular & cellular proteomics : MCP》2010,9(9):1819-1828
Characterization and interpretation of disease-associated alterations of protein glycosylation are the central aims of the emerging glycoproteomics projects, which are expected to lead to more sensitive and specific diagnosis and improve therapeutic outcomes for various diseases. Here we report a new approach to identify carbohydrate-targeting serum biomarkers, termed isotopic glycosidase elution and labeling on lectin-column chromatography (IGEL). This technology is based on glycan structure-specific enrichment of glycopeptides by lectin-column chromatography and site-directed tagging of N-glycosylation sites by 18O during the elution with N-glycosidase. The combination of IGEL with 8-plex isobaric tag for relative and absolute quantitation (iTRAQ) stable isotope labeling enabled us not only to identify N-glycosylation sites effectively but also to compare glycan structures on each glycosylation site quantitatively in a single LC/MS/MS analysis. We applied this method to eight sera from lung cancer patients and controls, and finally identified 107 glycopeptides in their sera, including A2GL_Asn151, A2GL_Asn290, CD14_Asn132, CO8A_Asn417, C163A_Asn64, TIMP1_Asn30, and TSP1_Asn1049 which showed the significant change of the affinity to Concanavalin A (ConA) lectin between the lung cancer samples and the controls (p < 0.05 and more than twofold change). These screening results were further confirmed by the conventional lectin-column chromatography and immunoblot analysis using additional serum samples. Our novel methodology, which should be valuable for diverse biomarker discoveries, can provide high-throughput and quantitative profiling of glycan structure alterations.Glycan structure variations often show highly organ-specific manners (1, 2), as well as those manners that correlate with diverse disease states, (3, 4) e.g., cancer and inflammation. Thus, the carbohydrates are currently attracting a great deal of attention as specific targets of cancer biomarkers and therapy (5). In fact, certain changes of glycan structures are already in clinical use as serum biomarkers, such as AFP-L3 (6), and glycosylation at the specific site of therapeutic antibody proved to be essential for its therapeutic effect (7). Advances in proteomic technologies and analysis have stimulated a great interest in application of MS to identify glycosylation sites (8, 9) or analyze glycan structures (10, 11) from various biological specimens, but the comprehensive techniques which allow quantitative profiling of glycan structures on each glycosylation site have not been developed.The two major issues facing recent glycoproteomic studies are the difficulties in glycopeptide-specific enrichment tools involving lectin-column chromatography and the detection of glycopeptides in mass spectrometers. In the conventional lectin-column chromatography experiments, glycoprotein enrichment from complicated protein mixtures, such as human sera, resulted in a heavy contamination of hapten sugar, salts, and nonspecific proteins caused by protein-protein interactions of serum proteins (12). Even when the digested peptide mixture was subjected to the lectin-column chromatography, salt contamination and the eluting sugar-dependent biases of elution efficiency were inevitable. Moreover, the straightforward analysis of the eluted glycopeptides by MS was hardly possible without further deglycosylation and desalting steps.In this study we report our new approach for the identification of carbohydrate-targeting biomarkers, termed isotopic glycosidase elution and labeling on lectin-column chromatography (IGEL),1 which is based on glycan structure-specific enrichment of glycopeptides by lectin- column chromatography and site-directed labeling of N-glycosylation sites by water-18O during the elution with N-glycosidase. We combined this method with 8-plex isotobaric tag for relative and absolute quantitation (iTRAQ) labeling for relative quantification of glycopeptides and applied them to search for carbohydrate-targeting serum biomarkers in lung cancer patient sera. 相似文献
994.
995.
996.
M. J. Micallef Kenshi Yoshida Sachiko Kawai Toshiharu Hanaya Keizo Kohno Shigeyuki Arai Tadao Tanimoto Kakuji Torigoe Mitsukiyo Fujii Masao Ikeda Masashi Kurimoto 《Cancer immunology, immunotherapy : CII》1997,43(6):361-367
Interferon-γ-inducing factor/interleukin-18 is a novel cytokine that reportedly augments natural killer (NK) activity in
human and mouse peripheral blood mononuclear cell cultures in vitro and has recently been designated IL-18. In this study,
IL-18 exhibited significant antitumor effects in BALB/c mice challenged intraperitoneally (i.p.) with syngeneic Meth A sarcoma
when administered i.p. on days 1, 2 and 3 after challenge. Intravenous (i.v.) administration also induced antitumor effects
in the tumor-bearing mice; however, subcutaneous (s.c.) administration did not. When mice were twice pretreated with 1 μg
IL-18 3 days and 6 h before tumor challenge, all mice survived whereas control mice died within 3 weeks of challenge. Inhibitory
effects on Meth A cell growth in vitro were not observed with either IL-18 or interferon γ. The effects of IL-18 pretreatment
were abrogated by abolition of NK activity after mice had been injected with anti-asialo GM1 antibody 48 h before and, 24
h and 72 h after tumor challenge. Mice pretreated with IL-18 and surviving tumor challenge resisted rechallenge with Meth
A cells but could not reject Ehrlich ascites carcinoma, and spleen cells from the resistant mice, but not control mice, exhibited
cytotoxic activity against Meth A cells in vitro after restimulation with mitomycin C-treated Meth A cells for 5 days. The
effector cells in the spleen cell preparations from resistant mice appear to be CD4+ cells because cytolytic activity was significantly inhibited after depletion of this subset by monoclonal antibodies and
complement. In conclusion, IL-18 exhibits in vivo immunologically (primarily NK) mediated antitumor effects in mice challenged
with syngeneic Meth A sarcoma and induces immunological memory and the generation of cytotoxic CD4+ cells.
Received: 17 September 1996 / Accepted: 8 November 1996 相似文献
997.
Cytogenetic studies were performed on two types of Japanese hagfish (Eptatretus okinoseanus) that eliminate about 45% (type A) and 55% (type B) of their DNA from presumptive somatic cells during the differentiation of somatic cells. The observations revealed inter- and intraindividual variations in the number of chromosomes in germ cells of both types of hagfishes. Although the modal number of chromosomes in the germ cells was 54 in both types, the percentage of cells with the modal number was rather low (38.6% [51/132] in five specimens of type A and 22.7% [25/110] in eight specimens of type B). In addition, one of seven type B specimens clearly had a modal number of 62 chromosomes. Another specimen of type B had a bimodal distribution of chromosome numbers, with peaks of 54 and 59 chromosomes. The observation of interindividual variations was supported by data on the amount of DNA in germ cells of type B specimens. However, these variations were rarely observed in somatic cells. These results suggest that supernumerary (B) chromosomes are maintained in germ cells and are eliminated together with some other chromosomes and/or chromatin from somatic cells. 相似文献
998.
Stability of YACs Containing Ribosomal or RCP/GCP Locus DNA in Wild-type S. cerevisiae and RAD Mutant Strains 总被引:1,自引:0,他引:1
Kohno Kyoko; Wada Morimasa; Schlessinger David; D'urso Michele; Tanabe Sumiko; Oshiro Tomoko; Imamoto Fumio 《DNA research》1994,1(4):191-199
About 2% of human YAC clones, including tandemly repeated segmentscolor vision pigment DNA, ribosomal DNA and alphoid DNA havebeen reported to be inherently unstable in yeast hosts, producingmore stable deletion products. YACs containing color visionred pigment gene DNA or 1.5 rDNA tandem repeat units were transformedinto hosts bearing lesions at the RAD1, RAD6, RAD51, or RAD52loci. YACs susceptible to deletion during outgrowth of wild-typecells (or in preliminary experiments, in RAD6 transformants)were stable for up to 100 generations or more in the other strains.Thus both the RAD1 and RAD51/RAD52 epistatic pathways are apparentlyinvolved in the instability of YACs containing tandem repeatloci, presumably during recombination-based deletion formation;and a yeast host disarmed in these pathways will likely maintainYACs intact that are otherwise unstable. 相似文献
999.
ABSTRACT: Extraskeletal myxoid chondrosarcoma (EMC) is a rare soft-tissue sarcoma, which primarily occurs deep in the extremities, especially in skeletal muscle, or tendon. EMC of the pleura has been described, however, no case of primary EMC arising from lung has been previously reported. We describe herein, a 51-year-old Asian female initially manifested with signs of severe anemia who presented with a lung mass unrelated to pleura that was morphologically typical EMC, with strong immunoreactivity for vimentin and NSE. Two weeks after resection, the anemia was cured. The patient continued with follow-up, without sign of abnormality 32 months after operation.Virtual slidesThe virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2882199847396682. 相似文献
1000.