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61.
Erika HAYASHI Sayaka WAKAYAMA Daiyu ITO Ayumi HASEGAWA Keiji MOCHIDA Masatoshi OOGA Atsuo OGURA Teruhiko WAKAYAMA 《The Journal of reproduction and development》2022,68(2):118
Mammalian embryos are most commonly cryopreserved in liquid nitrogen; however, liquid nitrogen is not available in special environments, such as the International Space Station (ISS), and vitrified embryos must be stored at −80°C. Recently, the high osmolarity vitrification (HOV) method was developed to cryopreserve mouse 2-cell stage embryos at −80°C; however, the appropriate embryo is currently unknown. In this study, we compared the vitrification resistance of in vivo-derived, in vitro fertilization (IVF)-derived, and intracytoplasmic sperm injection (ICSI)-derived mouse 2-cell embryos against cryopreservation at −80°C. The ICSI embryos had lower survival rates after warming and significantly lower developmental rates than the in vivo and IVF embryos. Further, IVF embryos had a lower survival rate after warming, but a similar rate to the in vivo embryos to full-term development. This result was confirmed by simultaneous vitrification of in vivo and IVF embryos in the same cryotube using identifiable green fluorescent protein-expressing embryos. We also evaluated the collection timing of the in vivo embryos from the oviduct and found that late 2-cell embryos had higher survival and developmental rates to full-term than early 2-cell embryos. Some early 2-cell embryos remained in the S-phase, whereas most late 2-cell embryos were in the G2-phase, which may have affected the tolerance to embryo vitrification. In conclusion, when embryos must be cryopreserved under restricted conditions, such as the ISS, in vivo fertilized embryos collected at the late 2-cell stage without long culture should be employed. 相似文献
62.
Ying-Hong He Sayaka Isono Yoko Kawaguchi-Ito Akito Taneda Ken-ichi Kondo Akihiko Iijima Kazuaki Tanaka Teruo Sano 《Journal of General Plant Pathology》2010,76(5):324-330
A 303-nucleotide viroid was isolated from an apple tree (Malus × domestica, ‘Fuji’) cultivated in Japan. The viroid had 84.9% overall nucleotide sequence homology to Apple dimple fruit viroid (ADFVd), a member of Pospiviroidae, reported from Italy. This viroid differed from the Italian variant by 47 mutations (38 substitutions, six deletions and three insertions), and most of these mutations occurred on either side of the central conserved region. The leaves and branches of the infected trees did not have any disease symptoms, but the fruits were dimpled and yellow. The infected scions were top-grafted onto a healthy ‘Fuji’ apple tree, which tested positive for this viroid in a northern hybridization analysis, and yellow dimple fruits were produced in the second growing season. We propose that this viroid is a new variant of ADFVd and causes yellow dimple fruit formation in ‘Fuji’ apple trees. 相似文献
63.
Xiu‐Lian Ju Sayaka Fusazaki Hiroyuki Hishinuma Xiaomu Qiao Izumi Ikeda Yoshihisa Ozoe 《Pest management science》2010,66(9):1002-1010
BACKGROUND: Bicyclophosphorothionates (2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane‐1‐sulfides) are blockers (or non‐competitive antagonists) of γ‐aminobutyric acid (GABA) receptor channels. Twenty‐two bicyclophosphorothionates with different 3‐ and 4‐substituents were synthesised, and [3H]4′‐ethynyl‐4‐n‐propylbicycloorthobenzoate (EBOB) binding assays were performed to evaluate their affinities for housefly and rat GABA receptors. RESULTS: Introduction of an isopropyl group at the 3‐position enhanced the affinity of bicyclophosphorothionates for housefly GABA receptors and reduced the affinity towards rat GABA receptors. The 4‐isopentyl‐3‐isopropylbicyclophosphorothionate showed the highest affinity for housefly GABA receptors (IC50 = 103 nM ) among the analogues tested, while the 4‐cyclohexylbicyclophosphorothionate showed the highest affinity for rat GABA receptors (IC50 = 125 nM ). Among the bicyclophosphorothionates synthesised to date, the former analogue exhibited the highest selectivity for housefly GABA receptors, with an IC50rat/IC50fly ratio of approximately 97. Three‐dimensional GABA receptor models successfully explained the structure–activity relationships of the bicyclophosphorothionates. CONCLUSION: The results indicate that minor structural modifications of blockers can change their selectivity for insect versus mammalian GABA receptors. The substituent at the 3‐position of the bicyclophosphorothionates dictates selectivity for housefly versus rat GABA receptors. This information should prove useful for the design of safer insecticides and parasiticides. Copyright © 2010 Society of Chemical Industry 相似文献
64.
Kazunari USHIDA Takahiro SEGAWA Sayaka TSUCHIDA Koichi MURATA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):251-257
Preservation of indigenous gastrointestinal microbiota is deemed to be critical for successful captivebreeding of endangered wild animals, yet its biology is poorly understood. Here, we investigated cecalbacterial communities in wild Japanese rock ptarmigans (Lagopus muta japonica) and comparedthem with those in Svalbard rock ptarmigans (L. m. hyperborea) in captivity. Ultra-deepsequencing of 16S rRNA gene indicated that the community structure of cecal microbiota in wild rock ptarmiganswas remarkably different from that in captive Svalbard rock ptarmigans. Fundamental differences betweenbacterial communities in the two groups of birds were detected at the phylum level. Firmicutes,Actinobacteria, Bacteroidetes and Synergistetes were the major phyla detected in wild Japanese rockptarmigans, whereas Firmicutes alone occupied more than 80% of abundance in captive Svalbard rock ptarmigans.Furthermore, unclassified genera of Coriobacteriaceae, Synergistaceae, Bacteroidaceae, Actinomycetaceae,Veillonellaceae and Clostridiales were the major taxa detected in wild individuals, whereas in zoo-rearedbirds, major genera were Ruminococcus, Blautia, Faecalibacterium andAkkermansia. Zoo-reared birds seemed to lack almost all rock ptarmigan-specific bacteria intheir intestine, which may explain the relatively high rate of pathogenic infections affecting them. We showevidence that preservation and reconstitution of indigenous cecal microflora are critical for successfulex situ conservation and future re-introduction plan for the Japanese rock ptarmigan. 相似文献
65.
Natsuki USHIGOME Sayaka WAKAYAMA Kango YAMAJI Daiyu ITO Masatoshi OOGA Teruhiko WAKAYAMA 《The Journal of reproduction and development》2022,68(4):262
Freeze-dried sperm (FD sperm) are of great value because they can be stored at room temperature for long periods of time, However, the birth rate of offspring derived from FD sperm is low and the step in the freeze-drying process particularly responsible for low offspring production remains unknown. In this study, we determined whether the drying process was responsible for the low success rate of offspring by producing vacuum-dried sperm (VD sperm), using mouse spermatozoa dried in a vacuum without being frozen. Transfer of embryos fertilized with VD sperm to recipients resulted in the production of several successful offspring. However, the success rate was slightly lower than that of FD sperm. The volume, temperature, and viscosity of the medium were optimized to improve the birth rate. The results obtained from a comet assay indicated that decreasing the drying rate reduced the extent of DNA damage in VD sperm. Furthermore, even though the rate of blastocyst formation increased upon fertilization with VD sperm, full-term development was not improved. Analysis of chromosomal damage at the two-cell stage through an abnormal chromosome segregation (ACS) assay revealed that reduction in the drying rate failed to prevent chromosomal damage. These results indicate that the lower birth rate of offspring from FD sperm may result from the drying process rather than the freezing process. 相似文献
66.
Nitrogen (N) budget was estimated with dissolved inorganic N (DIN) and dissolved organic N (DON) in a forested mountainous watershed in Tsukui, Kanagawa Prefecture, about 50 km west of Tokyo in Central Japan. The forest vegetation in the watershed was dominant by Konara oak (Quercus serrata) and Korean hornbeam (Carpinus tschonoskii), and Japanese cedar (Cryptomeria japonica). Nitrate (NO3 ?) concentration in the watershed streamwater was averagely high (98.0 ±± 19 (±± SD, n = 36) μmol L?1) during 2001–2003. There was no seasonal and annual changes in the stream NO? 3 concentration even though the highest N uptake rate presumably occurred during the spring of plant growing season, a fact indicating that N availability was in excess of biotic demands. The DON deposition rates (DON input rates) in open area and forest area were estimated as one of the main N sources, accounting for about 32% of total dissolved N (TDN). It was estimated that a part of the DON input rate contributed to the excessive stream NO? 3 output rate under the condition of the rapid mineralization and nitrification rates, which annual DON deposition rates were positively correlated with the stream NO3 ? output rates. The DON retention rate in the DON budget had a potential capacity, which contributed to the excessive stream NO? 3 output rate without other N contributions (e.g. forest floor N or soil N). 相似文献
67.
Mizuki MAEDA Sayaka KITAUCHI Tetsushi HIRANO Yoshinori IKENAKA Misaki NISHI Asuka SHODA Midori MURATA Youhei MANTANI Yoshiaki TABUCHI Toshifumi YOKOYAMA Nobuhiko HOSHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):542
Recently, it has been reported that neonicotinoid pesticides (NNs) are transferred from mother to child and are assumed to affect the next generation, but the behavioral effects of NN exposure at different developmental stages have not been investigated. We exposed mice to no-observed-adverse-effect level (NOAEL) doses of clothianidin (CLO) during the fetal and lactational period, and then evaluated the neurobehavioral effects in juvenile and adult mice. Significant increases in anxiety-like behavior and locomotor activity were observed in juveniles and adults, respectively, and neuronal activity and neurogenesis in the hippocampal dentate gyrus were affected in both stages. These results suggest that fetal and lactational exposure to CLO may inhibit neurogenesis and cause different behavioral abnormalities at different developmental stages. 相似文献
68.
Yuji IWATA Yoshihiro NAKASHIMA Sayaka TSUCHIDA Pierre Philippe Mbehang NGUEMA Chieko ANDO Kazunari USHIDA Juichi YAMAGIWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1247-1252
African rainforest harbors herbivores at high density. However, because plants and soils
typically lack in some essential minerals, rainforest is not always a suitable habitat for
herbivores. How they fulfill the mineral requirements is therefore an important question
to animal ecology and conservation. Although large marshes, called ‘bais’, are often
mentioned as efficient mineral-resource, little information on other sodium resources has
still been available. Our laboratory works and field surveys found that a peculiar item,
decaying wood stumps of Anthostema aubryanum, played as a major sodium
resource for herbivores in Moukalaba-Doudou National Park, Gabon. When A.
aubryanum is alive, the sodium content of its bark is low and its latex is
toxic. Sodium is accumulated in decaying stumps (mean=1,343 mg/kg dry matter). Eight
herbivores visited stumps to ingest the dead wood. Fecal sample analysis revealed that
western lowland gorillas, a species most-frequently using the stumps, consumed large
amount of the dead wood as regular food. Our findings suggest that decaying A.
aubryanum is critical sodium-resources and is a key species for herbivores in
our study area. Importance of the A. aubryanum may be particularly large
there, because it is a limited sodium-rich material that is available year round. Our
study site is known as the site where the densities of several herbivores are among the
highest at Central Africa. The relatively high herbivores density in our study site may
partly depend on decaying A. aubryanum as sodium resources. 相似文献
69.
Pierre Philippe MBEHANG NGUEMA Torahiko OKUBO Sayaka TSUCHIDA Shiho FUJITA Juichi YAMAGIWA Yutaka TAMURA Kazunari USHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):619-623
Prevalence of drug-resistant bacteria in wildlife can reveal the actual level of
anthropological burden on the wildlife. In this study, we isolated two multiple
drug-resistant strains, GG6-2 and GG6-1-1, from 27 fresh feces of wild western lowland
gorillas in Moukalaba-Doudou National Park, Gabon. Isolates were identified as
Achromobacter xylosoxidans and Providencia sp.,
respectively. Minimum inhibitory concentrations of the following 12 drugs—ampicillin
(ABPC), cefazolin (CEZ), cefotaxime (CTX), streptomycin (SM), gentamicin (GM), kanamycin
(KM), tetracycline (TC), nalidixic acid (NA), ciprofloxacin (CPFX), colistin (CL),
chloramphenicol (CP) and trimethoprim (TMP)—were determined. Isolate GG6-2 was resistant
to all antimicrobials tested and highly resistant to CTX, SM, TC, NA and TMP. Isolate
GG6-1-1 was resistant to ABPC, CEZ, TC, CL, CP and TMP. 相似文献
70.
Airanthi MK Sasaki N Iwasaki S Baba N Abe M Hosokawa M Miyashita K 《Journal of agricultural and food chemistry》2011,59(8):4156-4163
Brown seaweed lipids from Undaria pinnatifida (Wakame), Sargassum horneri (Akamoku), and Cystoseira hakodatensis (Uganomoku) contained several bioactive compounds, namely, fucoxanthin, polyphenols, and omega-3 polyunsaturated fatty acids (PUFA). Fucoxanthin and polyphenol contents of Akamoku and Uganomoku lipids were higher than those of Wakame lipids, while Wakame lipids showed higher total omega-3 PUFA content than Akamoku and Uganomoku lipids. The levels of docosahexaenoic acid (DHA) and arachidonic acid (AA) in liver lipids of KK-A(y) mouse significantly increased by Akamoku and Uganomoku lipid feeding as compared with the control, but not by Wakame lipid feeding. Fucoxanthin has been reported to accelerate the bioconversion of omega-3 PUFA and omega-6 PUFA to DHA and AA, respectively. The higher hepatic DHA and AA level of mice fed Akamoku and Uganomoku lipids would be attributed to the higher content of fucoxanthin of Akamoku and Uganomoku lipids. The lipid hydroperoxide levels of the liver of mice fed brown seaweed lipids were significantly lower than those of control mice, even though total PUFA content was higher in the liver of mice fed brown seaweed lipids. This would be, at least in part, due to the antioxidant activity of fucoxanthin metabolites in the liver. 相似文献