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1.
Yokoo M Shimizu T Kimura N Tunjung WA Matsumoto H Abe H Sasada H Rodriguez-Martinez H Sato E 《The Journal of reproduction and development》2007,53(2):263-270
Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte maturation in pigs. We demonstrate here in that CD44 has a key role in oocyte maturation but not in cumulus expansion. Previous studies have reported the physiological significance of cumulus expansion in oocyte maturation. However, our results suggest that cumulus expansion is a necessary condition for oocyte maturation, but that it is not sufficient on its own. Furthermore, western blot analysis demonstrated that the CD44 of the in vitro-matured cumulus-oocyte complexes (COCs) had a larger molecular weight and more terminal sialic acid, which has been proven to inhibit the hyaluronan-binding ability of the receptor, than the CD44 of the in vivo-matured COCs, indicating that the hyaluronan-CD44 interactions during in vitro maturation might be insufficient compared with those in vivo. The insufficient interactions of hyaluronan-CD44 during in vitro maturation may cause the inferior capacity of fertilization and development of oocytes matured in vitro. 相似文献
2.
Sequential leaching experiments using H2O, H2O2, NH4Cl, and HCl were performed on surface soils on an andesite substrate at four sites in the Kawakami mountainous area, central Japan. The solutions extracted from the dehydrated soil by H2O, H2O2, and NH4Cl have relatively constant ratios with respect to Ca, Mg, and Sr, while they have variable 87Sr/86Sr ratios depending on the site. The elemental ratios and Sr isotopes in the extracted solution are different from those of the soil minerals but identical to those of the soil solution and the plants. Sr isotopic data indicate that the residues after extraction from fine-grained minerals by NH4Cl and HCl are a mixture of acid-resistant minerals derived from bedrock and from arid areas in China. We suggest that there is a vital exchange of Sr and other cations between plants and the soil pool of exchangeable cations through the soil solution, while soil minerals, except chlorite, do not participate in the exchange reaction. 相似文献
3.
Udayanga KG Yamamoto K Miyata H Yokoo Y Mantani Y Takahara EI Kawano J Yokoyama T Hoshi N Kitagawa H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(5):597-605
The apoptosis process in rat esophageal epithelium was investigated using enzyme-immunohistochemistry and transmission electron microscopy. As a result, Fas and Fas-L were expressed in the epithelial cell membrane and cytoplasm from the stratum spinosum (SS) to the stratum granulosum (SG). No TNF-R1 show immunopositivity in the cell membranes. TNF-α and caspase-8 were not observed in any layer. Caspase-10, cleaved caspase-3, XIAP and DNase-1 were found in the epithelial cytoplasm from the SS to the SG, whereas Bid, Apaf-1 and cleaved caspase-9 were detected only in the SG. Cytochrome c was observed as cytoplasmic granular positivity from the stratum basale (SB) and altered into homogeneous immunopositivity in the SG. Bcl-2 and Bcl-X immunopositivity was detected in cytoplasm from the SB to the SG. Immunoreactions of Bak in the cytoplasm and Bax beneath the cell membrane were observed from the upper portion of the SS with increasing intensity toward the SG. In the sites with the hyperproliferation of indigenous bacteria, TNF-R1, TNF-α and caspase-8 were detected in the SG and the immunopositive intensities of Bid, Apaf-1 and cleaved caspase-9 were altered to be strong. Prominently swollen cells and decreased mitochondria were ultrastructurally confirmed in the uppermost layers of stratum corneum. These findings suggest that the Fas-Fas-L-interaction initially induces apoptosis through a mitochondria-independent pathway and secondarily through a mitochondria-dependent pathway, leading to eventual epithelial cell death in the rat esophageal epithelium. The bacterial stimuli probably enhance the mitochondria-dependent pathway through the TNF-R1-TNF-α interaction. 相似文献
4.
M.J. Yokoo L.G. Albuquerque R.B. Lbo L.A.F. Bezerra F.R.C. Araujo J.A.V. Silva R.D. Sainz 《Livestock Science》2008,117(2-3):147-154
The aim of the present study was to evaluate the genetic and environmental factors affecting records of longissimus muscle area (LMA) and backfat thickness (BF) obtained between the 12th and 13th ribs, and rump fat thickness (RF) between the hook and pin bones, measured by real-time ultrasound in Nelore cattle. Also, weight records of 22,778 animals born from 1998 to 2003, in ten farms across six Brazilian states were used. Carcass traits as measured by ultrasound of the live animal were recorded from 2002 to 2004 in 2590 males and females with ages varying from 450 to 599 days. Fixed models including farm, year and season of birth, sex and type of feed effects, and the covariates age of dam (AOD) and age of animal at measurement were used to study the effect of environmental factors on these traits. The genetic parameters for LMA, BF and RF were estimated with two and three-trait animal models with 120-day weights using a restricted maximum likelihood method. All environmental effects significantly affected carcass traits, with the exception of year of birth for BF and RF and AOD for LMA. The heritability estimates for LMA, BF and RF were 0.35, 0.51 and 0.39, respectively. Standard errors obtained in one-trait analyses were from 0.07 to 0.09. Genetic correlation estimates between LMA and the two traits of subcutaneous fat were low (close to zero) and 0.74 between BF and RF, indicating that the selection for LMA should not cause antagonism in the genetic improvement of subcutaneous fat measured by real-time ultrasound. 相似文献
5.
Michele R. S. Simões Joal J. B. Leal Alessandro P. Minho Cláudia C. Gomes Michael D. MacNeil Rodrigo F. Costa Vinícius S. Junqueira Patrícia I. Schmidt Fernando F. Cardoso Arione A. Boligon Marcos J. Yokoo 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(2):177-188
Our goal was to define a breeding objective for Brangus beef cattle in Brazil. Bioeconomic models were produced and used to estimate economic values (EVs). The scenarios simulated were typical full-cycle beef production systems that are used in tropical and subtropical regions. The breeding objective contained pregnancy rate (PR), warm carcass weight (WCW), mature cow weight (MCW), number of nematode eggs per gram of faeces (EPG) and tick count (TICK). Two models were used in series to estimate the EV. A deterministic model was used to simulate effects of PR, WCW and MCW on profitability with a constant parasite load. Subsequently, stochastic models were used to estimate economic values for TICK and EPG as consequences of their environmental effects on weight gains, mortality and health costs. The EV of PR, WCW, MCW, EPG and TICK, was US$1.59, US$2.11, −US$0.24, −US$5.35 and −US$20.88, respectively. Results indicate positive emphasis should be placed on PR (12.49%) and WCW (65.07%) with negative emphasis on MCW (13.92%), EPG (2.77%) and TICK (5.75%). In comparison with the indexes usually used, these results suggest a reformulation in the selection indexes of the beef production system in tropical and subtropical regions in order to obtain greater profitability. 相似文献
6.
Reaction between maleic anhydride (MA) and wood specimens was carried out in a vapor phase reaction system. Reaction conditions
such as the ratio of supplied MA to wood, initial moisture content, and reaction temperature were optimized. The MA supplied
to the reaction system was effectively absorbed by the wood, and a satisfactorily high dimensional stability was achieved
even at a low MA/wood ratio. The dimensional stability increased with rising initial moisture content. When the reaction was
conducted at an elevated temperature (180°C), high dimensional stability was attained without remarkable weight increase and
bulking. The mechanism of dimensional stabilization was discussed on the basis of the dimensional changes at high humidity
and during repeated water soaking and drying. It was shown that the dimensional stabilization arises mainly from a decrease
of hygroscopicity. When the reaction was conducted at 180°C, the formation of cross-links in the cell wall was apparent. Following
the MA treatment, the antifungal property was remarkably enhanced and met the Japanese Industrial Standard K1571. Therefore,
MA treatment in the vapor phase is an effective method to attain antifungal properties as well as high dimensional stability
with a small amount of nontoxic reagent. 相似文献
7.
Furuya Y Uchida K Tateyama S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1339-1341
A subcutaneous mass at the digit of the left-hind limb of a 12-year-old, male mongrel dog was examined. A white firm mass, approximately 1 x 2 cm in diameter, was excided surgically. Histopathologically, the mass formed multiple nodules consisting of mixed proliferation of round epithelioid cells arranged in cord or sheet-like structures and small spindle cells forming loose irregular bundles. The epithelioid cells often showed proliferation around the blood vessels. A few giant cells scattering in the neoplastic foci were observed. The neoplastic cells were positive for alpha-smooth muscle actin and vimentin, and were negative for cytokeratin (AE1/AE3), desmin, factor-VIII related antigen, S-100 protein, and neuron specific enolase. On the basis of these findings, this tumor was diagnosed as glomus tumor. Since the present neoplasm had neither recurrence nor distal metastasis during the 12 month after surgical resection, the biological natures of the present neoplasm are supposed to be benign. 相似文献
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10.
Takanori Nakano Yoriko Yokoo Masao Okumura Seo-Ryong Jean Kenichi Satake 《Water, air, and soil pollution》2012,223(9):5575-5597
To elucidate the influence of airborne materials on the ecosystem of Japan??s Yakushima Island, we determined the elemental compositions and Sr and Nd isotope ratios in streamwater, soils, vegetation, and rocks. Streamwater had high Na and Cl contents, low Ca and HCO3 contents, and Na/Cl and Mg/Cl ratios close to those of seawater, but it had low pH (5.4 to 7.1), a higher Ca/Cl ratio than seawater, and distinct 87Sr/86Sr ratios that depended on the bedrock type. The proportions of rain-derived cations in streamwater, estimated by assuming that Cl was derived from sea salt aerosols, averaged 81?% for Na, 83?% for Mg, 36?% for K, 32?% for Ca, and 33?% for Sr. The Sr value was comparable to the 28?% estimated by comparing Sr isotope ratios between rain and granite bedrock. The soils are depleted in Ca, Na, P, and Sr compared with the parent materials. At Yotsuse in the northwestern side, plants and the soil pool have 87Sr/86Sr ratios similar to that of rainwater with a high sea salt component. In contrast, the Sr and Nd isotope ratios of soil minerals in the A and B horizons approach those of silicate minerals in northern China??s loess soils. The soil Ca and P depletion results largely from chemical weathering of plagioclase and of small amounts of apatite and calcite in granitic rocks. This suggests that Yakushima??s ecosystem is affected by large amounts of acidic precipitation with a high sea salt component, which leaches Ca and its proxy (Sr) from bedrock into streams, and by Asian dust-derived apatite, which is an important source of P in base cation-depleted soils. 相似文献