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61.
The effects of five polybrominated diphenol ethers from a Marine Sponge, Phyllospongia dendyi, on the relative plating efficiencies in V79 cells and the cell proliferation and IL-8 production in PMA-stimulated HL-60 cells were examined. Three compounds, possessing two phenol units, were reported to inhibit the assembly of microtubule proteins and showed the inhibition of colony formation of V79 cells and increase in IL-8 production. Interestingly, a monomethoxy compound exhibited the stronger activity than the three active compounds in both bioassays. This compound did not inhibit the assembly of microtubule proteins. A dimethoxy compound was not active in either bioassays. In these experimental conditions, the biological activities were not high, but in future, these compounds will be expected to be made stronger by structural modifications.  相似文献   
62.
Journal of General Plant Pathology - Viruses that infect Ranunculus asiaticus L., a globally important greenhouse ornamental, have consistently caused serious damage in Japan. We coupled...  相似文献   
63.
N,N-Didesmethylgrossularine-1 (DDMG-1), a compound with a rare α-carboline structure, was isolated from an Indonesian ascidian Polycarpa aurata as responsible for the observed inhibitory activity against TNF-α production in lipopolysaccharide-stimulated murine macrophage-like RAW264.7 cells. DDMG-1 inhibited the mRNA level of mTNF-α, IκB-α degradation, and binding of NF-κB to the target DNA site in LPS-stimulated RAW 264.7 cells. Moreover, DDMG-1 had an inhibitory effect on the production of IL-8, which is produced in CD14+-THP-1 cells stimulated by LPS. DDMG-1 is thus a promising drug candidate lead compound for the treatment of chronic inflammatory diseases, such as rheumatoid arthritis.  相似文献   
64.
Kasuya M  Olivier AR  Ota Y  Tojo M  Honjo H  Fukui R 《Phytopathology》2006,96(12):1372-1379
ABSTRACT Suppressive effects of soil amendment with residues of 12 cultivars of Brassica rapa on damping-off of sugar beet were evaluated in soils infested with Rhizoctonia solani. Residues of clover and peanut were tested as noncruciferous controls. The incidence of damping-off was significantly and consistently suppressed in the soils amended with residues of clover, peanut, and B. rapa subsp. rapifera 'Saori', but only the volatile substance produced from water-imbibed residue of cv. Saori exhibited a distinct inhibitory effect on mycelial growth of R. solani. Nonetheless, disease suppression in such residue-amended soils was diminished or nullified when antibacterial antibiotics were applied to the soils, suggesting that proliferation of antagonistic bacteria resident to the soils were responsible for disease suppression. When the seed (pericarps) colonized by R. solani in the infested soil without residues were replanted into the soils amended with such residues, damping-off was suppressed in all cases. In contrast, when seed that had been colonized by microorganisms in the soils containing the residues were replanted into the infested soil, damping-off was not suppressed. The evidence indicates that the laimosphere, but not the spermosphere, is the site for the antagonistic microbial interaction, which is the chief principle of soil suppressiveness against Rhizoctonia damping-off.  相似文献   
65.
Fisheries Science - In the original publication the text in right column of page 330, the sequences of primers were incorrectly published as.  相似文献   
66.
The reference compound (9), with a partial structure of acteoside, was synthesized to elucidate the relation between structural features and the precipitation or solubility of the oxidation products of acteoside: 2-(3,4-dihydroxyphenyl)-ethyl 3-O-(-L-rhamnopyranosyl)--D-glucopyranoside (9). The glycosyl acceptor 2-O-benzoyl-3-O-(2,3,4-tri-O-acetyl--L-rhamnopyranosyl)-4,6-O-benzylidene--D-glucopyranosyl trichloroacetimidate (7) was prepared from allyl 2-O-benzoyl-3-O-(2,3,4-tri-O-acetyl--L-rhamnopyranosyl)-4,6-O-benzylidene--D-glucopyranoside (4) via isomerization of the allyl group with an iridium complex to the 1-propenyl group and its hydrolysis with HgCl2lHgO, followed by treatment with CCl3CN and DBU in a 65.5% overall yield. The glycosyl acceptor 3,4-diacetoxyphenethyl alcohol (16) was prepared from homoveratric acid via demethylation with 57% HI and its acetylation with Ac2O and 85% H3PO4, followed by selective reduction of the carboxyl group to the alcohol with a borane-tetrahydrofurane complex in a 61% overall yield. The glycosylation of7 with16 in dichloromethane promoted by BF3-Et2O gave a 74.3% yield of8. Hydrolysis of8 with 90% CF3COOH gave the debenzylidenated product, which was treated with NaOMe to afford a 32% overall yield of the desired compound9. This compound9 was identical with the natural specimen.This study was presented in part at the 46th annual meeting of the Japan Wood Research Society, Kumamoto, April 3–5, 1996  相似文献   
67.
We have recently isolated four new melophlins P (1), Q (2), R (3), and S (4) together with seven known melophlins A (5), D (6), E (7), G (8), H (9), I (10), and O (11) from two marine sponges of the genus Melophlus collected in Palau. In this study, the influence of these compounds on the colony formation of Chinese hamster V79 cells and the production of IL-8 in PMA-stimulated HL-60 cells were examined. These 11 compounds did not show any effect on IL-8 production. The EC50 values of compounds 2, 3, 4, 5, 7, 9, 10, and 11 against V79 cells were 44.0, 13.3, 16.7, 27.2, 19.8, 8.5, 23.1, and 9.6 μM, respectively. The linear-chain-type compounds (1, 6, and 8) were not active against V79 cells at 50 μM. Although the growth inhibitory activity of these melophlins was not remarkable, some structure-activity relationships of these compounds against V79 and murine leukemia L1210 cells were observed.  相似文献   
68.
The relationship between the taxa of airborne fungi and the decay risk was investigated. Airborne fungi in 1,000 l of air were trapped on Japanese cedar disks, and incubated in a damp container kept at 26oC. After 16-week incubation, filamentous fungi grown on the disks were isolated and DNA extracted from each isolate was amplified with the primers ITS4/ITS5. The DNA sequences of the amplified products were determined and compared to the sequence data of GenBank to determine the species or genus according to a BLAST search. This search revealed that the isolate consisted of 5 major taxa, namely Bjerkandera sp., Phanerochaete sp. (A), Phanerochaete sp. (B), Polyporales sp. Polyporus arcularius, and 6 minor ones. Statistical analysis revealed that the major taxa were trapped on the disks in similar weather conditions except for Bjerkandera sp., which was trapped at a cooler temperature. The analysis also proved the disks to which Phanerochaete spp. or Polyporales sp. were attached showed higher mass loss. It is concluded that, under these experimental conditions, related species of Phanerochaete sordida play an important role in increasing the decay risk caused by airborne wood-decay fungi.  相似文献   
69.
Although some clinical studies have suggested that spironolactone (SPL), a mineralocorticoid receptor (MR) antagonist, appears to increase the blood glucose levels, experimental studies have not supported this notion. Here, we investigated the effect of SPL on blood glucose levels in SHR/NDmcr-cp(cp/cp) (ND) rats, an animal model of metabolic syndrome, in comparison with that of eplerenone (EPL), another MR antagonist. At the same dose of 100 mg/kg, SPL and EPL increased the urinary sodium-to-potassium ratio to a comparable extent, indicating that both agents have similar renal MR antagonistic efficacy in ND rats. Interestingly, SPL but not EPL significantly increased the level of blood glucose. The oral glucose tolerance test revealed that treatment with SPL led to glucose intolerance. The levels of serum insulin and adiponectin, regulators of the blood glucose level, were virtually unaffected by treatment with SPL. On the other hand, SPL induced a marked increase in the blood level of aldosterone, known to be a risk factor for insulin resistance. These results demonstrate that in comparison with EPL, SPL characteristically impairs glucose tolerance in an animal model of metabolic syndrome, in association with a higher blood level of aldosterone.  相似文献   
70.
To determine whether neurophysiological taste responses of young and old rats are different, recordings were made from the whole chorda tympani nerve which innervates taste buds on the anterior tongue. SHR-SP (Stroke-Prone Spontaneously Hypertensive Rats) in two age groups were studied. Chemical stimuli included single concentrations of 250 mM NH(4)Cl, 100 mM NaCl, 100 mM KCl, 500 mM sucrose, 20 mM quinine-hydrochloride, 10 mM HCl, 10 mM monosodium glutamate (MSG), 10 mM L- glutamic acid (L-Glu) and an NaCl concentration series. The magnitude of the neural response (response ratio) was calculated by dividing the amplitude of the integrated response by the amplitude of the spontaneous activity that preceded it. Substantial neural responses to all chemicals were obtained at both ages. The responses to KCl, sucrose, quinine-hydrochloride, HCl, monosodium glutamate (MSG) and glutamic acid (Glu) did not change with age, but the response to NaCl did decrease significantly. The profile of the response/concentration function for NaCl differed with age. In particular, the responses to solutions more concentrated than 100 mM NaCl were significantly weaker in aged than in young SHR-SPs. We also observed that recovery from amiloride treatment on the tongue of SHR-SPs was faster in aged rats than in young ones, suggesting that there is some functional difference in the sodium-specific channels on the taste cell. These results suggest that aged SHR-SP may be less able than young SHR-SPs to discriminate among higher concentrations of NaCl solutions.  相似文献   
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