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991.
André Eggen Mathieu Gautier Alain Billaut élisabeth Petit Hélène Hayes Pascal Laurent Catherine Urban Martha Pfister-Genskow Ken Eilertsen Michael D Bishop 《遗传、选种与进化》2001,33(5):543-548
A bovine artificial chromosome (BAC) library of 105 984 clones has been constructed in the vector pBeloBAC11 and organized in 3-dimension pools and high density membranes for screening by PCR and hybridization. The average insert size, determined after analysis of 388 clones, was estimated at 120 kb corresponding to a four genome coverage. Given the fact that a male was used to construct the library, the probability of finding any given autosomal and X or Y locus is respectively 0.98 and 0.86. The library was screened for 164 microsatellite markers and an average of 3.9 superpools was positive for each PCR system. None of the 50 or so BAC clones analysed by FISH was chimeric. This BAC library increases the international genome coverage for cattle to around 28 genome equivalents and extends the coverage of the ruminant genomes available at the Inra resource center to 15 genome equivalents. 相似文献
992.
993.
Development of a highly sensitive chemiluminescent assay for hydrogen peroxide under neutral conditions using acridinium ester and its application to an enzyme immunoassay
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Hidetoshi Arakawa Keiko Tsuruoka Ken‐ichi Ohno Noriko Tajima Hiromi Nagano 《Luminescence》2014,29(4):374-377
We developed a highly sensitive chemiluminescent (CL) assay for hydrogen peroxide using 10‐methyl‐9‐(phenoxycarbonyl) acridinium fluorosulfonate (PMAC) that produced chemiluminescence under neutral conditions and applied it to an enzyme immunoassay (EIA). One picomole of hydrogen peroxide could be detected using the optimized PMAC‐CL method and 6.2 × 10‐20 mol β‐d ‐galactosidase (β‐gal) could be detected by combining an indoxyl derivative substrate and the proposed PMAC‐CL method. This highly sensitive CL β‐gal assay was applied to an EIA for thyroid‐stimulating hormone (TSH) using β‐gal as a label enzyme; 0.02–100.0 μU/mL TSH in human serum could be assayed directly and with high reproducibility. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
994.
Hidehiko Kondo Iichiro Shimomura Ken Kishida Hiroshi Kuriyama Yasunaka Makino Hitoshi Nishizawa Morihiro Matsuda Norikazu Maeda Hiroyuki Nagaretani Shinji Kihara Yoshihisa Kurachi Tadashi Nakamura Tohru Funahashi Yuji Matsuzawa 《European journal of biochemistry》2002,269(7):1814-1826
Aquaporin adipose (AQPap), which we identified from human adipose tissue, is a glycerol channel in adipocyte [Kishida et al. (2000) J. Biol. Chem. 275, 20896-20902]. In the current study, we determined the genomic structure of the human AQPap gene, and identified three AQPap-like genes that resembled (approximately 95%) AQPap, with little expression in human tissues. The AQPap promoter contained a putative peroxisome proliferator response element (PPRE) at -46 to -62, and a putative insulin response element (IRE) at -542/-536. Deletion of the PPRE abolished the pioglitazone-mediated induction of AQPap promoter activity in 3T3-L1 adipocytes. Deletion and single base pair substitution analysis of the IRE abolished the insulin-mediated suppression of the human AQPap gene. Analysis of AQPap sequence in human subjects revealed three missense mutations (R12C, V59L and G264V), and two silent mutations (A103A and G250G). The cRNA injection of the missense mutants into Xenopus oocytes revealed the absence of the activity to transport glycerol and water in the AQPap-G264V protein. In the subject homozygous for AQPap-G264V, exercise-induced increase in plasma glycerol was not observed in spite of the increased plasma noradrenaline. We suggest that AQPap is responsible for the increase of plasma glycerol during exercise in humans. 相似文献
995.
Enhancement of maternal recognition of pregnancy with parthenogenetic embryos in bovine embryo transfer 总被引:1,自引:0,他引:1
Hiroki Hirayama Satoru Moriyasu Soichi Kageyama Ken Sawai Hitomi Takahashi Masaya Geshi Takashi Fujii Takeshi Koyama Keisuke Koyama Akio Miyamoto Motozumi Matsui Akira Minamihashi 《Theriogenology》2014
This study was performed to elucidate the changes in IFNT messenger RNA (mRNA) levels in in vivo–fertilized and parthenogenetic bovine embryos and their interferon-τ (IFNT) secretion amounts during the elongation phase. We assessed the induction capability of maternal recognition of pregnancy by parthenogenetic embryos and attempted cotransfer of in vivo–fertilized and parthenogenetic embryos. The expression level of IFNT mRNA in in vivo–fertilized embryos peaked on Day 18 after estrus, and the highest amount of uterine IFNT was observed on Day 20. Transfer of 10 parthenogenetic embryos produced a detectable amount of uterine IFNT. Transfer of one or three parthenogenetic embryos inhibited luteolysis. An increase in ISG15 mRNA levels in peripheral granulocytes was induced by the transfer of three parthenogenetic embryos. Cotransfer of three parthenogenetic embryos significantly improved the pregnancy rate on Day 40 in code 3 in vivo–fertilized embryos compared with single transfer without parthenogenetic embryos (65% vs. 35%). However, the pregnancy rate on Day 90 (35%) in cotransfer of code 3 in vivo–fertilized embryos did not differ from that upon single transfer (29%), because the cotransfer group had a higher incidence of pregnancy loss than with single transfer (47% vs. 17%) after Day 40. Cotransfer did not affect the pregnancy rate of code 2 in vivo–fertilized embryos. The incidence of pregnancy loss was higher in cotransfer of code 2 in vivo–fertilized embryos than in single transfer (30% vs. 7%). In conclusion, parthenogenetic embryos in the elongation phase secreted IFNT, enabling induction of maternal recognition of pregnancy. The present study revealed that enhancement of the maternal recognition of pregnancy using parthenogenetic embryos promoted the viability of poor-quality embryos until Day 40 of gestation. However, the incidence of pregnancy loss increased after Day 40 in the cotransfer of parthenogenetic embryos. A technique for promoting the full-term survival of poor-quality embryos is needed. 相似文献
996.
Microbial Community in Black Rust Exposed to Hot Ridge Flank Crustal Fluids 总被引:1,自引:0,他引:1
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Satoshi Nakagawa Fumio Inagaki Yohey Suzuki Bjrn Olav Steinsbu Mark Alexander Lever Ken Takai Bert Engelen Yoshihiko Sako Charles Geoffrey Wheat Koki Horikoshi Integrated Ocean Drilling Program Expedition Scientists 《Applied microbiology》2006,72(10):6789-6799
During Integrated Ocean Drilling Program Expedition 301, we obtained a sample of black rust from a circulation obviation retrofit kit (CORK) observatory at a borehole on the eastern flank of Juan de Fuca Ridge. Due to overpressure, the CORK had failed to seal the borehole. Hot fluids from oceanic crust had discharged to the overlying bottom seawater and resulted in the formation of black rust analogous to a hydrothermal chimney deposit. Both culture-dependent and culture-independent analyses indicated that the black-rust-associated community differed from communities reported from other microbial habitats, including hydrothermal vents at seafloor spreading centers, while it shared phylotypes with communities previously detected in crustal fluids from the same borehole. The most frequently retrieved sequences of bacterial and archaeal 16S rRNA genes were related to the genera Ammonifex and Methanothermococcus, respectively. Most phylotypes, including phylotypes previously detected in crustal fluids, were isolated in pure culture, and their metabolic traits were determined. Quantification of the dissimilatory sulfite reductase (dsrAB) genes, together with stable sulfur isotopic and electron microscopic analyses, strongly suggested the prevalence of sulfate reduction, potentially by the Ammonifex group of bacteria. Stable carbon isotopic analyses suggested that the bulk of the microbial community was trophically reliant upon photosynthesis-derived organic matter. This report provides important insights into the phylogenetic, physiological, and trophic characteristics of subseafloor microbial ecosystems in warm ridge flank crusts. 相似文献
997.
Takumi Chinen Kaho Yamazaki Kaho Hashimoto Ken Fujii Koki Watanabe Yutaka Takeda Shohei Yamamoto Yuka Nozaki Yuki Tsuchiya Daisuke Takao Daiju Kitagawa 《The Journal of cell biology》2021,220(2)
The pericentriolar material (PCM) that accumulates around the centriole expands during mitosis and nucleates microtubules. Here, we show the cooperative roles of the centriole and PCM scaffold proteins, pericentrin and CDK5RAP2, in the recruitment of CEP192 to spindle poles during mitosis. Systematic depletion of PCM proteins revealed that CEP192, but not pericentrin and/or CDK5RAP2, was crucial for bipolar spindle assembly in HeLa, RPE1, and A549 cells with centrioles. Upon double depletion of pericentrin and CDK5RAP2, CEP192 that remained at centriole walls was sufficient for bipolar spindle formation. In contrast, through centriole removal, we found that pericentrin and CDK5RAP2 recruited CEP192 at the acentriolar spindle pole and facilitated bipolar spindle formation in mitotic cells with one centrosome. Furthermore, the perturbation of PLK1, a critical kinase for PCM assembly, efficiently suppressed bipolar spindle formation in mitotic cells with one centrosome. Overall, these data suggest that the centriole and PCM scaffold proteins cooperatively recruit CEP192 to spindle poles and facilitate bipolar spindle formation. 相似文献
998.
Chris M Cirimotich Jaclyn C Scott Aaron T Phillips Brian J Geiss Ken E Olson 《BMC microbiology》2009,9(1):49
Background
Arthropod-borne viruses (arboviruses) can persistently infect and cause limited damage to mosquito vectors. RNA interference (RNAi) is a mosquito antiviral response important in restricting RNA virus replication and has been shown to be active against some arboviruses. The goal of this study was to use a recombinant Sindbis virus (SINV; family Togaviridae; genus Alphavirus) that expresses B2 protein of Flock House virus (FHV; family Nodaviridae; genus Alphanodavirus), a protein that inhibits RNAi, to determine the effects of linking arbovirus infection with RNAi inhibition. 相似文献999.
Though researchers have studied lowland gray langurs extensively, there is little information about the Himalayan populations.
We provide foraging data from a field study of Himalayan langurs in Langtang National Park, Nepal at 3000–4000 m elevation.
Phenological records show marked seasonality in resource abundance, with extremely low availability in winter, increasing
abundance in spring and monsoon, and a reduction in fall. Activity budgets indicated greater time devoted to feeding as total
vegetation abundance decreased. Diet included leaf buds, ripe fruit, and evergreen mature leaves in winter; deciduous young
leaves in spring; and deciduous mature leaves in the monsoon and fall. Supplemental resources, such as underground storage
organs, bark, and herbaceous vegetation, were also seasonally important. Among plant part classes included in the phenological
sample, abundance and consumption correlate positively for all primary food resources except evergreen mature leaves and unripe
fruit. Daily path lengths varied by season and, when controlled for overall vegetation abundance, positively relate to the
consumption of soft underground storage organs, fruits, and deciduous mature leaves. The results contradict the common generalization
of leaves as ubiquitous or nonpatchy resources. 相似文献
1000.
Katsuhiko Mikoshiba Shinichi Kohsaka Ken Takamatsu Yasuzo Tsukada 《Journal of neurochemistry》1981,37(1):186-191
Abstract: The 2-deoxyglucose autoradiographic method has been used to study activity in cerebellum of the weaver and nervous mutant mice. Patterns of 2-deoxyglucose incorporation into the cerebral hemispheres from weaver and nervous strains did not differ significantly from those of the controls. In the normal cerebellum, 2-deoxyglucose incorporation was maximal in the granular layer, where mossy fibers form synapses with the dendrites of granule cells. In the cerebellum of nervous mice, which lacks Purkinje cells, the incorporation of the 2-deoxyglucose was maximal in the granular layer, but the incorporation into the molecular layer appeared less than in the control. The incorporation into the cerebellum from weaver, which lacks granule cells, was much higher than that of the control, the maximal incorporation being found in the Purkinje cell layer and in cell masses located in the white matter. These data suggest that the heterologous synapses that mossy fibers or climbing fibers form with the cells in the Purkinje cell layer and the cells in the white matter in the weaver cerebellum are functional. 相似文献