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81.
M. I. Tajul Takayuki Motoyama Akikazu Hatanaka M. Sariah Hiroyuki Osada 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):91-100
Four green-odour compounds—trans-2-hexenal, cis-3-hexenol, n-hexanal, and cis-3-hexenal—were applied (0.85 μg ml−1 as vapour) to rice plants in laboratory conditions to observe their biological activity against the phytopathogenic fungus
Maganporthe oryzae, which causes rice blast disease worldwide. Two compounds, trans-2-hexenal and cis-3-hexenal, showed remarkable disease suppression efficacy (99.7% and 100% suppression, respectively), while n-hexanal had moderate (86.5%) and cis-3-hexenol had weak (20.8%) disease-suppressing effects. Pre-application and post-application of trans-2-hexenal or cis-3-hexenal had slight effects on blast incidence, suggesting that these compounds had direct effects to suppress M. oryzae infection. In fact, trans-2-hexenal and cis-3-hexenal exhibited a growth suppression effect on M. oryzae. Interestingly, these two compounds inhibited appressorium formation at lower concentrations than the growth suppression.
Studies on the hypersensitive response (HR)-like reaction and plant β-1,3-glucanase activity in rice plant confirmed that
induced resistance was not the major factor involved in the disease suppression mechanism. Results of this study conclusively
showed that trans-2-hexenal and cis-3-hexenal possess potent inhibitory activities against the growth and the appressorium formation of M. oryzae and could be used as antifungal agents to significantly reduce M. oryzae infections in rice. 相似文献
82.
Tong Ly Hiroyuki Fukuoka Asami Otaka Atsushi Hoshino Shigeru Iida Eiji Nitasaka Nobuyoshi Watanabe Tsutomu Kuboyama 《Breeding Science》2012,62(1):99-104
Although Japanese morning glory (Ipomoea nil (L.) Roth.) has been used intensively for genetic studies, DNA markers have not been developed in Ipomoea nil sufficient to cover all chromosomes. Therefore, we conducted microsatellite (simple sequence repeats, SSR) marker development in I. nil for future genetic studies. From 92,662 expressed sequence tag (EST) sequences, 514 unique microsatellite-containing ESTs were identified. Primer pairs were designed automatically in 326 SSRs. Of 150 SSRs examined, 75 showed polymorphisms among strains. A phenogram based on the SSR genotypes revealed the genetic relation among seven Japanese morning glories from five different regions of the world and an ivyleaf morning glory (I. hederacea Jacq.). The developed SSR markers might be applicable for genetic studies of morning glories and their relatives. 相似文献
83.
Sakai H Murakami M Mishima H Hoshino Y Mori T Maruo K Yanai T 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2012,41(2):291-294
A 10-year-old intact female Shetland Sheepdog with tenesmus had a subcutaneous mass at the left ventral aspect of the anus. On cytologic examination, 2 types of cells were observed. Most of the cells were oval to polygonal and had elliptical or elongate nuclei and a moderate amount of pale to basophilic cytoplasm. The remaining cells had round to oval nuclei and pale to basophilic cytoplasm. Cells of both types were loosely adhered to each other and were arranged in rosette-like structures. Both neoplastic cell types had fine homogenous chromatin and either a small indistinct nucleolus or no visible nucleolus. Mild anisokaryosis and anisocytosis were observed. Histologically, the mass consists of glandular structures formed by cuboidal cells admixed with bundles of spindle cells. Eosinophilic PAS- and Alcian blue-positive secretory material was found in the center of some glandular structures. Both neoplastic cell types had positive staining with paradoxical concanavalin A and expressed cytokeratin, but not vimentin, S-100, α-smooth muscle actin, or desmin. Based on location and histologic and immunohistochemical features, the final diagnosis was adenocarcinoma of the apocrine gland of the anal sac, which should be included as a cytologic differential diagnosis when spindle cells and typical epithelial cells are observed in masses in the region of the anal sac of dogs. 相似文献
84.
Mori E Fukuda H Imajoh-Ohmi S Mori T Takasaki S 《The Journal of reproduction and development》2012,58(1):117-125
Although the importance of carbohydrate recognition by sperm during egg zona pellucida binding has been widely reported, the sperm molecular species that recognize the carbohydrates are poorly characterized. Our previous cytochemical study indicated that two kinds of carbohydrate-binding proteins are expressed on porcine sperm heads-one recognizes N-acetyllactosamine (Galβ1-4GlcNAc-), and the other recognizes the Lewis X structure (Galβ1-4(Fucα1-3)GlcNAc-). For this report, we used proteomic techniques to characterize the sperm proteins that bind N-acetyllactosamine. Porcine sperm plasma membrane was solubilized with a detergent solution and subjected to sequential chromatography with dextran sulfate agarose, affinity, and hydroxyapatite, and the binding activities in the eluates were monitored by a solid-phase binding assay. The tryptic peptides of two proteins most likely associated with the binding activities were subjected to tandem mass spectrometry sequencing. A subsequent database search identified one of the two proteins as predicted disintegrin and metalloprotease domain-containing protein 20-like (XP_003128672). The other protein was identified as disintegrin and metalloprotease domain-containing protein 5 (AB613817) by database searches for homologous amino acid sequences, cDNA cloning, nucleotide sequencing and nucleotide database searches. Furthermore, two-dimensional blue native/SDS-PAGE demonstrated that they formed a variety of non-covalent complexes. Therefore, these ADAM complexes probably are responsible for the N-acetyllactosamine-binding activity. An affinity-purified fraction containing these ADAM complexes showed zona pellucida-binding activity, though the activity was relatively weak, and the presence of another zona pellucida-binding protein that probably works in concert with these ADAM complexes was suggested. Immunofluorescence testing suggested that ADAM20-like was localized on the anterior part of the sperm plasma membrane. 相似文献
85.
Five oleanolic acid triterpenoid saponins (OTS-1, 2, 3, 4 and 5) were isolated from the rhizome of Anemone raddeana. The effect of these triterpenoid saponins on stimulus-induced superoxide generation in human neutrophils was assayed by measuring the reduction of ferricytochrome c using a dual-beam spectrophotometer. The phosphorylation of neutrophil proteins, and translocation of p67(phox), p47(phox) and Rac to plasma membrane were investigated using specific monoclonal antibodies. The five oleanolic acid triterpenoid saponins used in this experiment suppressed N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner. OTS-1, 2 and 4 suppressed phorbol 12-myristate 13-acetate (PMA)- and arachidonic acid (AA)-induced superoxide generation in a concentration-dependent manner, but OTS-3 and 5 showed no effect. fMLP- and PMA-induced tyrosyl or serine/threonine phosphorylation, and fMLP-, PMA- and AA-induced translocation of p67(phox), p47(phox) and Rac to plasma membrane were in parallel with the suppression of the stimulus-induced superoxide generation. 相似文献
86.
Both stem and crown mass affect tree resistance to uprooting 总被引:1,自引:0,他引:1
Tsutomu Urata Masato Shibuya Akio Koizumi Hiroyuki Torita JooYoung Cha 《Journal of Forest Research》2012,17(1):65-71
To examine the hypothesis that both stem and crown mass affect the resistance of a tree to uprooting and that tree resistance
increases with increasing crown mass, we conducted tree-pulling experiments on three Picea glehnii plantations (stands A, B, and C: 27–32 years old) that differed in tree density and slenderness ratio. Allometries between
crown and stem masses and between the critical uprooting moment and stem mass differed significantly among the three stands,
with the crown mass and critical moment significantly larger in stand C than in stands A or B, despite the same stem mass.
These results quantitatively verified our hypothesis. Allometries between crown and stem masses and between critical uprooting
moment and stem mass were highly significant in each stand but were stand specific. Therefore, these allometries can be used
to estimate tree resistance to uprooting in a given stand but not for data compiled from stands of various conditions and
tree shapes. The allometry between critical moment and aboveground mass did not differ among the three Picea stands; thus, it is not stand specific and is generally appropriate to use for estimating tree resistance. To increase tree
resistance to uprooting, we recommend light management for Picea glehnii plantations and probably other coniferous plantations as well. 相似文献
87.
Michimasa Oguri Kanji Okano Hajime Ieki Masayuki Kitagawa Osamu Tadokoro Yoshinori Sano Kazato Oishi Hiroyuki Hirooka Hajime Kumagai 《Animal Science Journal》2013,84(9):650-655
Three types of bamboo pellets as a ruminant feed: P1 (ground bamboo (GB) cultured with the fungus Ceriporiopsis subvermispora (CGB) : soybean curd residue (T) : soy sauce cake (S) in a 5:4:1 ratio on a dry matter (DM) basis); P2 (GB : T : S = 5:4:1 on a DM basis); and P3 (CGB : T : S = 5.5:0.8:3.7 on a DM basis) were prepared. Four wethers were assigned in a 4 × 4 Latin square design experiment to evaluate the applicability of the bamboo pellets. The experimental treatments were C (control): fed alfalfa hay cubes (AC) only, and T1, T2 and T3: fed P1, P2, and P3 with AC by 1:1 on a DM basis, respectively. The digestibility of the DM, organic matter and acid detergent fiber of P1 were significantly higher than those of P2 and P3 (P < 0.05). The total digestible nutrient (TDN) contents of AC, P1, P2 and P3 were 56.5%, 60.2%, 53.2% and 47.0%, respectively. No significant differences in nitrogen retention or ruminal pH and NH3 were observed among the treatment groups. The results indicate that bamboo pellets cultured with C. subvermispora and mainly mixed with soybean curd residue improved nutritional quality of ground bamboo because of its high digestibility and TDN content. 相似文献
88.
Kosei Ando Mayu Mizutani Yusuke Taniguchi Hiroyuki Yamamoto 《Journal of Wood Science》2013,59(4):290-298
To understand the viscoelasticity of wood three dimensionally, matched samples of Japanese cypress were loaded in uniaxial tensile creep in the longitudinal (L), radial (R), and tangential (T) directions at approximately 9.7 % equilibrium moisture content. Longitudinal and transverse strains were measured for the determination of viscoelastic Poisson’s ratios and three-dimensional viscoelastic compliance tensors concerning the normal strain. The changes in the transverse strains showed the same tendencies as those in the longitudinal strains, in all directions of loading. That is, during creep, the absolute value of transverse strain continued to increase with the gradual reduction in the increase rate; immediately after the removal of the load, it recovered rapidly, after which it continued to recover slowly. The transverse strain increased most easily in the T direction, followed by R and L, during creep. All the viscoelastic Poisson’s ratios and the absolute values of all elements of the viscoelastic compliance increased logarithmically with creep time. The three-dimensional viscoelastic compliance matrix for Japanese cypress is concluded to be asymmetric. 相似文献
89.
Fuminori TANIHARA Michiko NAKAI Hiroyuki KANEKO Junko NOGUCHI Takeshige OTOI Kazuhiro KIKUCHI 《The Journal of reproduction and development》2013,59(4):385-392
In porcine oocytes, the function of the zona pellucida (ZP) with regard to sperm
penetration or prevention of polyspermy is not well understood. In the present study, we
investigated the effects of the ZP on sperm penetration during in vitro
fertilization (IVF). We collected in vitro-matured oocytes with a first
polar body (ZP+ oocytes). Some of them were freed from the ZP (ZP− oocytes) by two
treatments (pronase and mechanical pipetting), and the effects of these treatments on
sperm penetration parameters (sperm penetration rate and numbers of penetrated sperm per
oocyte) were evaluated. There was no evident difference in the parameters between the two
groups. Secondly, we compared the sperm penetration parameters of ZP+ and ZP− oocytes
using frozen-thawed epididymal spermatozoa from four boars. Sperm penetration into ZP+
oocytes was found to be accelerated relative to ZP− oocytes. Thirdly, we evaluated the
sperm penetration of ZP+ and ZP− oocytes at 1−10 h after IVF (3 h gamete co-incubation).
The proportions of oocytes penetrated by sperm increased significantly with time in both
groups; however, the number of penetrated sperm per oocyte did not increase in ZP−
oocytes. Finally, we performed IVF using ZP− oocytes divided into control (3 h) and
prolonged gamete co-incubation (5 h) groups. Greater numbers of sperm penetrated in the 5
h group than in the control group. These results suggest that the ZP and oolemma are not
competent factors for prevention of polyspermy in our present porcine IVF system. However,
it appears that ZP removal is one of the possibilities for reducing polyspermic
penetration in vitro in pigs. 相似文献