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11.
Ammonia fungi of iriomote Island in the southern Ryukyus,Japan and a new ammonia fungus,Hebeloma luchuense 总被引:1,自引:1,他引:0
Species composition and fruiting season of ammonia fungi were investigated in Iriomote Island of the southern Ryukyus, Okinawa Prefecture, Japan.Castanopsis andPinus forests were surveyed and 10 species of ammonia fungi were collected, including one new agaric species,Hebeloma luchuense sp. nov. This new fungus is characterized by having a rooting, squamulose-scaly stipe and cortinate veil and forms ectomycorrhizae withCastanopsis cuspidata var.sieboldii. Although the general mushroom season in theCastanopsis forest in Iriomote island was very short and restricted to summer, ammonia fungi were observed to fruit throughout the year in urea-treated plots. 相似文献
12.
Polygalacturonase-inhibiting protein accumulates in Phaseolus vulgaris L. in response to wounding, elicitors and fungal infection 总被引:7,自引:0,他引:7
Carl W. Bergmann Yuki Ito Darrell Singer Peter Albersheim Alan G. Darvill Nicole Benhamou Laurence Nuss Giovanni Salvi Felice Cervone Giulia De Lorenzo 《The Plant journal : for cell and molecular biology》1994,5(5):625-634
Polygalacturonase-inhibiting protein (PGIP) is a cell wall-associated protein that specifically binds to and inhibits the activity of fungal endopolygalacturonases. The Phaseolus vulgaris gene encoding PGIP has been cloned and characterized. Using a fragment of the cloned pgip gene as a probe in Northern blot experiments, it is demonstrated that the pgip mRNA accumulates in suspension-cultured bean cells following addition of elicitor-active oligogalacturonides or fungal glucan to the medium. Rabbit polyclonal antibodies specific for PGIP were generated against a synthetic peptide designed from the N-terminal region of PGIP; the antigenicity of the peptide was enhanced by coupling to KLH. Using the antibodies and the cloned pgip gene fragment as probes in Western and Northern blot experiments, respectively, it is shown that the levels of PGIP and its mRNA are increased in P. vulgaris hypocotyls in response to wounding or treatment with salicylic acid. Using gold-labeled goat-anti-rabbit secondary antibodies in EM studies, it has also been demonstrated that, in bean hypocotyls infected with Colletotrichum lindemuthianum, the level of PGIP preferentially increases in those cells immediately surrounding the infection site. The data support the hypothesis that synthesis of PGIP constitutes an active defense mechanism of plants that is elicited by signal molecules known to induce plant defense genes. 相似文献
13.
Takashi Ninomiya Masumi Hirabayashi Junko Sagara Atsushi Yuki 《Molecular reproduction and development》1994,37(3):276-283
Fragments containing 5′ flanking regions of four bovine milk protein genes—alpha lactalbumin (bαLA), alpha S1 casein (bαS1CN), beta casein (bβCN), kappa casein (bkCN)—and mouse whey acidic protein (mWAP) gene were prepared by PCR and ligated to human growth hormone (hGH) gene. These recombinant DNAs were microinjected into rat embryos to produce transgenic rats, and the functions of the 5′ regions to direct secretion of hGH in the milk were tested. Although milk was obtained only in 5 of 19 mWAP/hGH rat lines, more than two-thirds of the rats carrying the other four DNAs produced milk. More than 80% of the lactated rats carrying bαLA/, bβCN/, and mWAP/hGH, and 33% of the laclated bαS1CN/hGH rats secreted detectable amounts of hGH (> 0.05 μg/ml) in the milk. In some rats, the hGH concentrations in the milk were comparable to or more than that of the corresponding milk protein in bovine milk. The ranges of hGH concentrations in the milk of bαLA/, bβCN/, bαS1CN/, and mWAP/hGH rats were 1.13–4,360 μg/ml, 0.11–10,900 μg/ml, 86.8–6,480 μg/ml, and 6.87–151 μg/ml, respectively. HGH was also detected in the sera of these rats, and some abnormalities of growth and reproduction were observed. All but one virgin mWAP/hGH rat secreted up to 0.0722 μg/ml of hGH in the serum, and more than half of them showed abnormal fat accumulations at their abdomen. None of the bαCN/hGH rats secreted detectable amount of hGH into their milk, whereas 8 of the 11 lines secreted hGH into their sera. For the production of hGH in transgenic rat milk, the 5′ region of bαS1CN was shown most suitable, because the bαS1CN/hGH rat secreted > 6,000 μg/ml of hGH into the milk and could be reproduced. © 1994 Wiley-Liss, Inc. 相似文献
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Pancreatic cancer is a highly aggressive form of cancer with a poor prognosis, partly due to ‘austerity’, a phenomenon of tolerance to nutrient deprivation and survival in its hypovascular tumor microenvironment. Anti-austerity agents which preferentially diminish the survival of cancer cells under nutrition starvation is regarded as new generation anti-cancer agents. This study investigated the potential of Piper longum constituents as anti-austerity agents. The ethanolic extract of Piper longum was found to have preferential cytotoxicity towards PANC-1 human pancreatic cancer cells in a nutrient-deprived medium (NDM). Further investigation led to the identification of pipernonaline ( 3 ) as the lead compound with the strongest anti-austerity activity, inducing cell death and inhibiting migration in a normal nutrient medium, as well as strongly inhibiting the Akt/mTOR/autophagy pathway. Therefore, pipernonaline ( 3 ) holds promise as a novel antiausterity agent for the treatment of pancreatic cancer. 相似文献
18.
The gonyaulacoid dinofiagellate Alexandrium satoanum Yuki et Fukuyo sp. nov. is described from Matoya Bay, Pacific coast of central Japan. The species is distinctive in its conical epitheca with almost straight sides and dorsal concavity of the hypotheca. The plate formula is Po, pc, 4′, 6″, 6c, 10s, 5″″, and 2″″, including two accessory plates inside the sulcus. The apical pore plate is triangular and possesses an anterior attachment pore at the right margin. The first apical plate does not make contact with the apical pore plate and lacks a ventral pore. A posterior attachment pore lies at the center of the posterior sulcal plate. In Matoya Bay, vegetative cells occur as solitary cells or sometimes in pairs during late spring and early summer in low concentrations. In connection with this study, the following new combination is proposed: Alexandrium pseudogonyaulax (Biecheler) Horiguchi ex Yuki et Fukuyo comb. nov. 相似文献
19.
Hidekazu Nishimura Kanetsu Sugawara Peng Gao Yasushi Muraki Seiji Hongo Fumio Kitame Kiyoto Nakamura 《Microbiology and immunology》1995,39(9):737-740
The HMV-II cells infected with influenza C virus were labeled with inorganic [32P]phosphate to identify phosphorylated proteins. Analysis by radioimmunoprecipitation with antiviral serum or monoclonal antibodies revealed that three major structural proteins of the virus, hemagglutinin-esterase (HE), nucleoprotein (NP), and matrix protein (M1) are all phosphorylated in both infected cells and virions. It was also observed that, in the presence of trypsin (10 μg/ml), the unphosphorylated form of the HE glycoprotein was cleaved efficiently whereas the phosphorylated form was not, raising the possibility that phosphorylation of HE may influence its susceptibility to degradation by proteolytic enzymes. 相似文献
20.
Le Van Phung Yuki Han Shiro Oka Hisako Hotta Michael D. Smith Prapit Theeparakun Eiko Yabuuchi Ikuya Yano 《FEMS immunology and medical microbiology》1995,12(3-4):259-264
Abstract The serodiagnosis of melioidosis is commonly performed with tests using protein or polysaccharide as antigen. However, due to the low sensitivity, specificity and difficulty in the preparation of the antigens, more simple, precise and reproducible diagnostic tests were required. A purified glycolipid antigen (GL) which is a specific lipid component of Burkholderia pseudomallei has been used in an ELISA. With this antigen, specific immunoglobulin G (IgG) was detected in 49 out of 50 melioidosis sera. IgG was also detected in 2 out of 185 (Japanese) and 16 out of 181 (Vietnamese) control sera. Thus, the sensitivity was 98.0%, and specificity was 98.9% and 91.1% in the Japanese and Vietnamese sera, respectively. When the ELISA and indirect haemagglutination (IHA) tests were combined, a sensitivity of 100% and specificity of 97.8% were achieved. The advantages of the glycolipid antigen are ease of preparation, stability, high sensitivity and specificity. 相似文献