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951.
Tamako MIYAZAKI Reiko UENOYAMA Takashi MATSUZAKI Tetsuro YAMASHITA Toh-ichi HIRATA Masao MIYAZAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):431
The blood luteinizing hormone (LH) surge in cows is well studied. However, little is known about urinary LH in cows. This study examined urinary LH concentrations after administration of gonadotropin-releasing hormone (GnRH) in six Japanese black cows to induce LH secretion from the pituitary gland into the bloodstream. Abrupt rises in plasma and urinary LH were observed after GnRH administration. Plasma and urinary LH peaked at 2 and 5 hr, respectively. A positive correlation was observed between plasma LH concentrations and urinary LH amounts. Ovulation was confirmed in the cows after 48 hr of GnRH administration. These data strongly suggest that urinary LH is derived from plasma LH, which triggers ovulation in cows. 相似文献
952.
Terumichi Kawahara Miki Kanouchi Yousuke Naniwa Masanori Koyago Takashi Numabe Keishi Mizutani Kentaro Tanemura Kenshiro Hara 《Animal Science Journal》2021,92(1):e13572
Aging is a major risk factor for spermatogenesis deterioration. However, the influence of age on spermatogenic stem cells and their progenitors in bulls is largely unknown. Here, we report age-related changes in undifferentiated and differentiating spermatogonia in Japanese Black cattle with nearly constant sperm output, by using spermatogonial markers. The numbers of differentiating spermatogonia and more differentiated spermatogenic cells were significantly decreased in aged bovine testes compared with those in young testes. In contrast, the number of undifferentiated spermatogonia was maintained, and their proliferative activity did not differ significantly between young and aged bovine testes. Although severe calcification was only observed to a small extent in aged testes, fewer Sertoli cells and interstitial fibrosis were observed in noncalcified testicular regions. These results suggest that, even in old bulls with nearly constant sperm output, testicular spermatogenic activity declined whereas undifferentiated spermatogonia numbers were maintained. Thus, we propose that undifferentiated spermatogonia may be resistant to age-related changes in bovine testes. Because undifferentiated spermatogonia may contain stem cell activity, our findings highlight the potential utility of undifferentiated spermatogonia as an agricultural resource to produce spermatozoa beyond the natural bovine lifetime through transplantation and in vitro spermatogenesis in future animal production. 相似文献
953.
Tanaka T Mine C Inoue K Matsuda M Kouno I 《Journal of agricultural and food chemistry》2002,50(7):2142-2148
Oxidation products of (-)-epicatechin and (-)-epigallocatechin by treatment with homogenates of 62 plants belonging to 49 families were compared. Forty-six plants were capable of synthesizing theaflavin, a black tea pigment, regardless of whether they contained catechins. Loquat, Japanese pear, and blueberry had activities higher than that of fresh tea leaves after 5 h of treatment; furthermore, these plants oxidized theaflavin to theanaphthoquinone. An additional new metabolite, dehydrotheasinensin, was generated on treatment with fresh tea leaves, eggplant, and unripened Japanese orange. Evidence for the oxidation of epigallocatechin and theaflavin by electron transfer to epicatechin quinone was demonstrated in a time course study using bananas and trapping the quinone intermediates as glutathione conjugates. 相似文献
954.
Ogo S Kabe R Uehara K Kure B Nishimura T Menon SC Harada R Fukuzumi S Higuchi Y Ohhara T Tamada T Kuroki R 《Science (New York, N.Y.)》2007,316(5824):585-587
Models of the active site in [NiFe]hydrogenase enzymes have proven challenging to prepare. We isolated a paramagnetic dinuclear nickel-ruthenium complex with a bridging hydrido ligand from the heterolytic cleavage of H2 by a dinuclear NiRu aqua complex in water under ambient conditions (20 degrees C and 1 atmosphere pressure). The structure of the hexacoordinate Ni(mu-H)Ru complex was unequivocally determined by neutron diffraction analysis, and it comes closest to an effective analog for the core structure of the proposed active form of the enzyme. 相似文献
955.
Imura A Tsuji Y Murata M Maeda R Kubota K Iwano A Obuse C Togashi K Tominaga M Kita N Tomiyama K Iijima J Nabeshima Y Fujioka M Asato R Tanaka S Kojima K Ito J Nozaki K Hashimoto N Ito T Nishio T Uchiyama T Fujimori T Nabeshima Y 《Science (New York, N.Y.)》2007,316(5831):1615-1618
alpha-klotho was identified as a gene associated with premature aging-like phenotypes characterized by short lifespan. In mice, we found the molecular association of alpha-Klotho (alpha-Kl) and Na+,K+-adenosine triphosphatase (Na+,K+-ATPase) and provide evidence for an increase of abundance of Na+,K+-ATPase at the plasma membrane. Low concentrations of extracellular free calcium ([Ca2+]e) rapidly induce regulated parathyroid hormone (PTH) secretion in an alpha-Kl- and Na+,K+-ATPase-dependent manner. The increased Na+ gradient created by Na+,K+-ATPase activity might drive the transepithelial transport of Ca2+ in cooperation with ion channels and transporters in the choroid plexus and the kidney. Our findings reveal fundamental roles of alpha-Kl in the regulation of calcium metabolism. 相似文献
956.
Alinne da Silva Raffaella Rossetto Juliana Bombecini Michel Piemonte Takashi Muraoka 《Journal of plant nutrition》2014,37(8):1227-1236
Vinasse is a liquid residue applied as a fertilizer in sugarcane crops. However, in areas far away from sugarcane mills the cost of the distribution can be very high due, the large volume of water. So, one solution is to concentrate the vinasse by the evaporation process to reduce transport costs. Considering that the nitrogen mineralization kinetics is not known in concentrated vinasse, the objective of this study was to evaluate the net and potential nitrogen mineralization in soil that received vinasse concentrated and not concentrated. The treatments with concentrated vinasse provided the highest values of net mineralization and total nitrogen, which presented significant correlation each other, the same way as the potential mineralization values had a positive correlation with the doses and the amounts of total nitrogen. The total nitrogen values can be used as an index of nitrogen availability in soils that received concentrated vinasse. 相似文献
957.
Tsuchiyama A Uesugi M Matsushima T Michikami T Kadono T Nakamura T Uesugi K Nakano T Sandford SA Noguchi R Matsumoto T Matsuno J Nagano T Imai Y Takeuchi A Suzuki Y Ogami T Katagiri J Ebihara M Ireland TR Kitajima F Nagao K Naraoka H Noguchi T Okazaki R Yurimoto H Zolensky ME Mukai T Abe M Yada T Fujimura A Yoshikawa M Kawaguchi J 《Science (New York, N.Y.)》2011,333(6046):1125-1128
Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time. 相似文献
958.
Suh J Rivest AJ Nakashiba T Tominaga T Tonegawa S 《Science (New York, N.Y.)》2011,334(6061):1415-1420
Associating temporally discontinuous elements is crucial for the formation of episodic and working memories that depend on the hippocampal-entorhinal network. However, the neural circuits subserving these associations have remained unknown. The layer III inputs of the entorhinal cortex to the hippocampus may contribute to this process. To test this hypothesis, we generated a transgenic mouse in which these inputs are specifically inhibited. The mutant mice displayed significant impairments in spatial working-memory tasks and in the encoding phase of trace fear-conditioning. These results indicate a critical role of the entorhinal cortex layer III inputs to the hippocampus in temporal association memory. 相似文献
959.
Akihisa T Tokuda H Yasukawa K Ukiya M Kiyota A Sakamoto N Suzuki T Tanabe N Nishino H 《Journal of agricultural and food chemistry》2005,53(3):562-565
Six azaphilones, monascin (1), ankaflavin (2), rubropunctatin (3), monascorburin (4), rubropunctamine (5), and monascorburamine (6), two furanoisophthalides, xanthomonasin A (7) and xanthomonasin B (8), and two amino acids, (+)-monascumic acid (9) and (-)-monascumic acid (10), isolated from the extracts of Monascus pilosus-fermented rice (red-mold rice) were evaluated for their inhibitory effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in mice, on the induction of Epstein-Barr virus early antigen (EBV-EA) by TPA in Raji cells, and on the activation of (+/-)-(E)-methyl-2[(E)-hydroxy-imino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitric oxide (NO) donor. Among the compounds tested, seven compounds (1-6 and 10) on TPA-induced inflammation, and six compounds (1, 3-5, 9, and 10) on EBV-EA activation, exhibited potent inhibitory effects. All of the compounds tested showed moderate inhibitory effects on NOR 1 activation. 相似文献
960.
Yoshimura T Kuribara H Matsuoka T Kodama T Iida M Watanabe T Akiyama H Maitani T Furui S Hino A 《Journal of agricultural and food chemistry》2005,53(6):2052-2059
The applicability of quantifying genetically modified (GM) maize and soy to processed foods was investigated using heat treatment processing models. The detection methods were based on real-time quantitative polymerase chain reaction (PCR) analysis. Ground seeds of insect resistant GM maize (MON810) and glyphosate tolerant Roundup Ready (RR) soy were dissolved in water and were heat treated by autoclaving for various time intervals. The calculated copy numbers of the recombinant and taxon specific deoxyribonucleic acid (DNA) sequences in the extracted DNA solution were found to decrease with time. This decrease was influenced by the PCR-amplified size. The conversion factor (Cf), which is the ratio of the recombinant DNA sequence to the taxon specific DNA sequence and is used as a constant number for calculating GM% at each event, tended to be stable when the sizes of PCR products of two DNA sequences were nearly equal. The results suggested that the size of the PCR product plays a key role in the quantification of GM organisms in processed foods. It is believed that the Cf of the endosperm (3n) is influenced by whether the GM originated from a paternal or maternal source. The embryos and endosperms were separated from the F1 generation seeds of five GM maize events, and their Cf values were measured. Both paternal and maternal GM events were identified. In these, the endosperm Cf was lower than that of the embryo, and the embryo Cf was lower than that of the endosperm. These results demonstrate the difficulties encountered in the determination of GM% in maize grains (F2 generation) and in processed foods from maize and soy. 相似文献