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121.
Local habitat use by botos (Amazon river dolphins,Inia geoffrensis) using passive acoustic methods 下载免费PDF全文
Yukiko Yamamoto Tomonari Akamatsu Vera M. F. da Silva Shiro Kohshima 《Marine Mammal Science》2016,32(1):220-240
We monitored the underwater behavior of botos (Inia geoffrensis) using stereo acoustic data loggers to observe their local habitat use and its diel changes at the Mamirauá Sustainable Development Reserve, Brazil. A‐tags were set at five sites in three different habitat types: Lake (low current), Channel (middle current), and Junction (junction of two channels). The presence index during nighttime was significantly greater than during daytime in the Lake and Junction. Underwater movement was estimated from the changing pattern (trajectory) of the relative angle of the sound source from A‐tags. A staying‐type trajectory was dominant in the Lake, although the prevalence of moving‐type trajectory increased at night. More than 80% of detected trajectories were the staying type in the Junction, while moving‐type trajectories dominated in the Channel. The frequency of click trains was greatest in the Lake, followed by the Junction and Channels. The average interpulse interval, which reflects the mean target distance of echolocation, was shortest in the Lake, followed by the Junction and Channel. These results suggest that the botos used the Lake as their primary habitat for active behaviors like foraging, especially at night, and the Junction as their primary habitat for relatively inactive behaviors at night. 相似文献
122.
An acid carboxypeptidase (EC 3.4.16.1) has been isolated from the culture filtrate of a wood-degrading Basidiomycete, Pycnoporus sanguineus and the molecular and enzymatic properties of the enzyme were determined. The extracellular acid carboxypeptidase was homogeneous on polyacrylamide gel electrophoresis at pH 9.4 and SDS-disc gel electrophoresis. The MWs as determined by gel filtration and SDS-gel electrophoresis were 50 000 and 54 000, respectively. The isoelectric point was pH 4.78 using electrofocusing. The purified enzyme had a pH optimum of 3.4, a Km of 0.74 mM and a kcat of 16/sec with benzyloxycarbonyl-l-glutamyl-l-tyrosine. The Km and kcat values for bradykinin at pH 3.4 and 30° were 2.0 mM and 25/sec. Values for angiotensin at pH 3.4 and 30° were 0.76 mM and 2.4/sec, respectively. 相似文献
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124.
The genetic basis of negative selection of Tcrb-Vll+ T cells 总被引:1,自引:0,他引:1
Non-H-2 genes responsible for negative selection of Tcrb-V 11+ T cells were examined using backcross mice of various strains with C58, which does not delete Tcrb-V 11+ T cells. Two independently segregating genes were found: one leading to partial deletion was closely linked toLy-2/Ly-3 on chromosome 6, and the second giving virtually complete deletion has not yet been mapped. The A strain had only the former, whereas BALB/c, BALBK, B10.BR, CBA-T6, C3H/He, and DBA/2 expressed both of these genes. Although a gene(s) of the NIH strain led only to partial deletion, the chromosomal localization of the gene(s) has not yet been determined: no informative polymorphic molecules are expressed from genes on chromosome 6 of this strain. 相似文献
125.
A rat antibody against a structure functionally related to the mouse T-cell receptor/T3 complex 总被引:14,自引:0,他引:14
Kyuhei Tomonari 《Immunogenetics》1988,28(6):455-458
126.
Makiko Horikawa Yosuke Kakiuchi Daiki Kashima Kenichiro Ogawa Masahiro Kawahara 《Biotechnology and bioengineering》2022,119(1):287-298
As protein–protein interactions (PPIs) are involved in many cellular events, development of mammalian cytosolic PPI detection systems is important for drug discovery as well as understanding biological phenomena. We have previously reported a c-kit-based PPI screening (KIPPIS) system, in which proteins of interest were fused with a receptor tyrosine kinase c-kit, leading to intracellular PPI-dependent cell growth. However, it has not been investigated whether PPI can be detected using other receptors. In this study, we employed a thrombopoietin receptor, which belongs to the Type I cytokine receptor family, to develop a thrombopoietin receptor-based PPI screening (THROPPIS) system. To improve the sensitivity of THROPPIS, we examined two strategies of (i) localization of the chimeric receptors on the cell membrane, and (ii) addition of a helper module to the chimeric receptors. Intriguingly, the nonlocalized chimeric receptor showed the best performance of THROPPIS. Furthermore, the addition of the helper module dramatically improved the detection sensitivity. In total, 5 peptide–domain interactions were detected successfully, demonstrating the versatility of THROPPIS. In addition, a peptide–domain interaction was detected even when insulin receptor or epidermal growth factor receptor was used as a signaling domain, demonstrating that this PPI detection system can be extended to other receptors. 相似文献
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128.
Mitsuhiro Wada Rie Kurogi Amal Kaddoumi Mihoko N Nakashima Kenichiro Nakashima 《Luminescence》2007,22(3):157-162
Pentazocine (PZ) in rat hair and plasma was determined by HPLC-fluorescence detection with 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoyl chloride (DIB-Cl) as a labelling reagent and cyclazocine (CZ) as an internal standard (IS). PZ and IS extracted from hair or plasma sample were derivatized with DIB-Cl and the resulted solution was cleaned up with solid phase extraction. The isocratic separation of DIB-PZ and -CZ within 20 min could be achieved by a Wakopak Handy-ODS column (250 x 4.6 mm i.d.) using a mobile phase composed of 0.1 mol/L acetate buffer (pH 6.2):acetonitrile (25:75, v/v). The detection limits of PZ at a signal-to-noise ratio of 3 for rat hair and plasma were 0.18 ng/mg and 0.57 ng/mL, respectively. Reproducible and precise results could be obtained by an IS method with RSD values less than 6.6% for within- and between-day measurements. The method was successfully applied for the monitoring of PZ levels in Zucker rat hair and plasma samples after a single administration of 25 mg/kg PZ. Moreover, incorporation rates of PZ into black and white hair of Zucker rat were evaluated. 相似文献
129.
One hundred and seventy three Cenozoic vertebrate track sites from Miocene to 1600 A.D have been reported in Japan. Three ichnofaunas can be recognized: a perissodactyl and artiodactyl ichnofauna in the Miocene, an artiodactyl and proboscidean ichnofauna in the Plio-Pleistocene, and human ichnofauna from about 900–800 B.C. to about 1400–1600 A.D. Track data indicate that a predominance of large vertebrates in fluvio-lacustrine environment in lowland changed from perissodactyls to proboscidean through Miocene to Plio-Pleistocene, and ancient people then occupied lowlands instead of large animals. Pes length of proboscidean tracks revealed temporal variation, and the relationship between proboscidean body sizes and tracks was observed. The Cenozoic Japanese proboscidean trackways can be distinguished on the basis of trackway width, as narrow- and wide-gauge, but the difference between of those narrow- and wide-gauge trackways probably indicates generic level differences. The Cenozoic Japanese bird tracks can be identified as four types: ?crane (Family Gruidae?), ?heron (Family Ardeidae?), ?stork (Family Ciconiidae?), and ?shorebird tracks. 相似文献
130.
Takahashi K Makita N Manaka K Hisano M Akioka Y Miura K Takubo N Iida A Ueda N Hashimoto M Fujita T Igarashi T Sekine T Iiri T 《The Journal of biological chemistry》2012,287(3):2099-2106
Inactivating mutations of the V2 vasopressin receptor (V2R) cause cross-linked congenital nephrogenic diabetes insipidus (NDI), resulting in renal resistance to the antidiuretic hormone AVP. In two families showing partial NDI, characterized by an apparently normal response to diagnostic tests and an increase in the basal ADH levels suggesting AVP resistance, we have identified two V2R mutations, Ser-333del and Y128S. Both mutant V2Rs, when expressed in COS-7 cells, show partial defects in vasopressin-stimulated cAMP accumulation and intracellular localization. The inhibition of internalization does not rescue their localization. In contrast, the non-peptide V2R antagonists OPC41061 and OPC31260 partially rescue the membrane localization and basal function of these V2R mutants, whereas they inhibit the basal activity of the wild-type V2R. These results indicate that a partial loss of function of Ser-333del and Y128S mutant V2Rs results from defective membrane trafficking. These findings further indicate that V2R antagonists can act as protean agonists, serving as pharmacological chaperones for inactivating V2R mutants and also as inverse agonists of wild-type receptors. We speculate that this protean agonism could underlie the possible dual beneficial effects of the V2R antagonist: improvement of hyponatremia with heart failure or polycystic kidney disease and potential rescue of NDI. 相似文献