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51.
Sasaki T Abe M Nakayama S Moriyama K Tahara H Takita T 《Bioscience, biotechnology, and biochemistry》2005,69(10):1898-1904
The effect of the heat-dried product of Shochu distillery by-products (HSDB) derived from sweet potato on mammary carcinogenesis in rats was investigated. HSDB was fed at 2.5% or 5% of the total feed weight. Dietary HSDB at the 5% level suppressed the incidence and number of tumors, and delayed the latency of mammary tumor development relative to the control diet. Experiments were conducted to determine the relative polarity of the anticarcinogenic constituent(s). The number of tumors per tumor-bearing rat was lower in the diet group fed with an ethyl acetate extract of HSDB than in the control group. The tumor incidence evaluated at both palpation and autopsy was slightly lower in the group fed with a methanol extract than in the control group. These results suggest that HSDB contained at least two constituents of differing polarity that counteracted mammary carcinogenesis. 相似文献
52.
Keiko?YamajiEmail author Yukiharu?Fukushi Yasuyuki?Hashidoko Satoshi?Tahara 《Ecological Research》2005,20(1):103-107
Picea glehnii seedlings are affected by damping-off fungi in nurseries. The aims of this study were (1) to isolate fungi grown in the seedling rhizosphere in forest soil of P. glehnii, (2) to select fungi that produce antifungal compounds against Pythium vexans, and (3) to examine whether or not selected fungi can protect seedlings from P. vexans. Penicillium frequentans from Picea glehnii seedling roots produced antibiotic penicillic acid. Penicillic acid did not cause significant phytotoxicity to the seedlings. Penicillium frequentans increased the average percentage of surviving seedlings when inoculated together with Pythium vexans, but the increase was not significant. Vigorous mycelial growth of P. frequentans around seedling roots seems to be one of the mechanisms for protection, but the amount of penicillic acid was too low to show antifungal activity in the seedling rhizosphere. 相似文献
53.
54.
Cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone, 1), known as a host-specific attractant towards the zoospores of Aphanomyces cochlioides, a cause of root rot and damping-off diseases of Chenopodiaceae, was found in the Amaranthaceae plant, Celosia cristata, that is susceptible to the pathogen. The content of 1 in Celosia seedlings was quantified as 1.4 microg/g fresh weight. A new isoflavone, cristatein (5-hydroxy-6-hydroxymethyl-7,2'-dimethoxyisoflavone, 2), and five known flavonoids were also identified. 相似文献
55.
56.
Sano S Okawa A Nakajima A Tahara M Fujita K Wada Y Yamazaki M Moriya H Sasho T 《Cell and tissue research》2006,323(2):245-252
To investigate the mechano-transduction system of cells, we identified genes responsive to a cyclic mechanical stimulus. MC3T3.E1
cells were cultured on a computer-controlled vacuum-pump-operated device designed to provide a cyclic mechanical stimulus.
A maximum elongation of 15% of membrane at 10 cycles/min (3 s extension followed by 3 s relax per cycle) was repeated for
48 h. By means of a differential display, the gene expression pattern of cells exposed to the stimulus was compared with that
of unexposed cells. As a result, a gene fragment that was exclusively expressed in mechanically stressed cells was identified.
By using expressed sequence tag walking together with the oligo-capping method, this gene was identified as phosphatidylinositol
4-phosphate 5-kinase type II β (initially known as Pip5k2β but now reclassified as Pip4k2β). The specific up-regulation of Pip4k2β upon mechanical stimulus was also confirmed by using another apparatus, viz. a computer-controlled linearized-stepping motor
system. To examine the involvement of the cyclic mechanical stimulus in the regulation of Pip4k2β expression in musculoskeletal tissue, we created an Achilles tendon transection model in rabbits. The temporal expression
of Pip4k2β was assessed by means of a quantitative reverse-transcribed polymerase chain reaction. In the gastrocnemius muscle, expression
of Pip4k2β rapidly decreased 1 week after transection but was restored to normal levels at 4 weeks. In the Achilles tendon, however,
expression remained decreased until 4 weeks after transection. We suggest that the expression of Pip4k2β can be used as a marker for cells receiving a suitable mechanical stimulus.
This study was supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, Sports and Culture
of Japan. 相似文献
57.
Aust G Wandel E Boltze C Sittig D Schütz A Horn LC Wobus M 《Cell and tissue research》2006,324(1):139-147
CD97, an epidermal growth factor (EGF)-TM7 receptor, is not restricted to hematopoetic and carcinoma cells but is also found
on smooth muscle cells (SMC). We have examined its location and biochemical structure in various normal and tumorigenic SMC-containing
tissues. SMC of the urinary bladder, lung bronchi and bronchioles, myometrium, and gastrointestinal tract were immunohistologically
stained by using monoclonal antibodies (mabs) to the CD97 stalk region (CD97stalk). Mabs directed against an N-glycosylation-dependent epitope within the EGF-domains (CD97EGF) did not bind to normal SMC. Vascular SMC, which was also CD97EGF-negative, showed further CD97 heterogeneity. Only a few, if any, SMC from the aorta or elastic arteries of the systemic circulation
were positive for CD97 mRNA and therefore also for CD97stalk. CD97stalk-positive SMC were slightly more numerous in muscular and peripheral arteries. In contrast, most venous SMC expressed CD97stalk. A comparison with other SMC molecules revealed a similar but not identical staining pattern for CD97stalk and desmin. Further CD97 heterogeneity was observed during SMC transformation. All leiomyomas (n=5) and nine out of 21 leiomyosarcomas were positive for both CD97stalk and CD97EGF. As expected, CD97EGF-positive SMC tumors expressed partly N-glycosylated CD97. Seven out of 21 leiomyosarcomas were completely devoid of CD97.
Thus, CD97 showed variable expression in vascular and biochemical modification in tumorigenic SMC, suggesting that the function
of the molecule is specific for the SMC subtype.
This study was supported by a joint grant from the German Research Council (DFG; project AU 132/3-1) and by the Interdisziplinary
Center of Clinical Research (IZKF) Leipzig at the Faculty of Medicine, University of Leipzig (project D6). E. Wandel is a
fellow of the IZKF. 相似文献
58.
59.
Amelioration of amyloid load by anti-Abeta single-chain antibody in Alzheimer mouse model 总被引:1,自引:0,他引:1
Fukuchi K Accavitti-Loper MA Kim HD Tahara K Cao Y Lewis TL Caughey RC Kim H Lalonde R 《Biochemical and biophysical research communications》2006,344(1):79-86
Parenteral immunization of transgenic mouse models of Alzheimer disease (AD) with synthetic amyloid beta-peptide (Abeta) prevented or reduced Abeta deposits and attenuated their memory and learning deficits. A clinical trial of immunization with synthetic Abeta, however, was halted due to brain inflammation, presumably induced by a toxic Abeta, T-cell- and/or Fc-mediated immune response. Another issue relating to such immunizations is that some AD patients may not be able to raise an adequate immune response to Abeta vaccination due to immunological tolerance or age-associated decline. Because peripheral administration of antibodies against Abeta also induced clearance of amyloid plaques in the model mice, injection of humanized Abeta antibodies has been proposed as a possible therapy for AD. By screening a human single-chain antibody (scFv) library for Abeta immunoreactivity, we have isolated a scFv that specifically reacts with oligomeric Abeta as well as amyloid plaques in the brain. The scFv inhibited Abeta amyloid fibril formation and Abeta-mediated cytotoxicity in vitro. We have tested the efficacy of the human scFv in a mouse model of AD (Tg2576 mice). Relative to control mice, injections of the scFv into the brain of Tg2576 mice reduced Abeta deposits. Because scFvs lack the Fc portion of the immunoglobulin molecule, human scFvs against Abeta may be useful to treat AD patients without eliciting brain inflammation. 相似文献
60.
Kakefuda A Suzuki T Tobe T Tahara A Sakamoto S Tsukamoto Si 《Bioorganic & medicinal chemistry》2002,10(6):1905-1912
In the search for a novel class of selective antagonists for the human V(1A) receptor, high-throughput screening (HTS) of the Yamanouchi chemical library using CHO cells expressing the cloned human V(1A) (hV(1A)) receptor led to the discovery of 5-(4-biphenyl)-4-(2-methoxyphenyl)-3-methyl-1,2,4-triazole (3) which possessed the novel 4,5-diphenyl-1,2,4-triazole structure. Subsequent structure-activity relationships studies on a series of the 4,5-diphenyl-1,2,4-triazole derivatives related to 3 revealed that the 4,5-diphenyl-1,2,4-triazole structure played an essential role in exerting high affinity for the hV(1A) receptor and that introduction of a basic amine moiety to the methoxy part of the 4-phenyl ring was effective in the improvement of both affinity for the hV(1A) receptor and selectivity versus the hV(2) receptor. Compound 3 and the 2-(morphorino)ethoxy derivative (11b) were shown to be antagonists for the hV(1A) receptor, from their effects on AVP-induced [Ca(2+)](i) response in CHO cells expressing the hV(1A) receptor. 相似文献