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51.
We previously reported that smenospongine, a sesquiterpene aminoquinone isolated from the marine sponge Dactylospongia elegans, showed antiproliferative or cytotoxic activities on leukemia cells. In this study, we investigated the effect of smenospongine on solid tumors. Since angiogenesis is well known to be closely involved in growth and metastasis of solid tumors, the antiangiogenic effect of smenospongine was determined. We found that smenospongine inhibited proliferation, migration and tube formation of human umbilical vein endothelial cells (HUVEC). Moreover, the inhibitory activity of smenospongine on growth of solid tumor cells was investigated. Smenospongine inhibited the growth of 39 human solid cancer cells in vitro, with a mean Log GI(50) value of -5.55. In conclusion, smenospongine exhibits antitumor activity on solid tumors via two mechanisms, an antiangiogenic effect on endothelial cells and direct inhibition of growth of tumor cells.  相似文献   
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To further our understanding of wood decay in living light red meranti (Shorea smithiana) trees, microscopic characteristics of the cell and cell wall degradations of S. smithiana wood in the presence of the decay fungi, the identity of the causal fungi, and the decay potential and pattern by an isolated fungus were investigated. Cell wall degradations, including cell wall thinning, bore holes formation, rounded pit erosion, and eroded channel opening were clearly observed under light and scanning electron microscopy. In transverse view, many large voids resulting from a coalition of degraded wood tissue appeared in the decayed canker zone. All these observations suggest the well-known simultaneous decay pattern caused by white-rot fungi. By phylogenetic analysis based on the sequences of internal transcribed spacer region of ribosomal DNA, a basidiomycete fungus isolated from the decayed wood was identified as Schizophyllum commune. The degradation caused by this fungus on sound S. smithiana wood in an in situ laboratory decay test was classified as the early stage of simultaneous decay, and showed a similar pattern to that observed in the wood samples naturally decayed.  相似文献   
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Shyamal C  MAHATA  Ryoichi  MITSUO  Jun-Ya  AOKI  Hironori  KATO  Takao  ITAKURA 《Fisheries Science》2003,69(3):615-624
ABSTRACT:     The cytochrome P450 (CYP) represents a large group of microsomal monooxygenases that catalyze drugs as well as a host of lethal environmental contaminants such as dioxins, leading to either detoxification and excretion from the animal or generation of carcinogenic intermediates. In the present study two forms of cDNA were cloned (Eu MC1 and Eu MC2) for European eel CYP1A genes by polymerase chain reaction (PCR) techniques. The cDNA of Eu MC1 was 3368 bp long coding 521 amino acid residues, and that of Eu MC2 was 2464 bp long coding 517 amino acid residues. Identities of deduced amino acid sequences between Eu MC1 and Japanese eel CYP1A1 and that between Eu MC2 and the second form of Japanese eel CYP1A were 98% and 97%, respectively, showing decisively that Eu MC1 and Eu MC2 are orthologous to Japanese eel CYP1A1 and the second form of CYP1A, respectively. A striking difference between the two eel species was that the Eu MC1 peptide was two amino acid residues longer than that of the Japanese eel CYP1A1. Existence of two loci of CYP1A in Japanese and European eels may suggest that the two forms of CYP1A exist widely among the eel species, because the divergence between the two eel species has been shown to be close to the basal divergence among eels. The identities in CYP1A may help to estimate genetic distance between European and Japanese eels.  相似文献   
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A 4-year-old male Shiba dog initially presented with pain of an undetermined origin and hypersensitivity to touch. Seven days later, the dog developed ataxia, hind-leg weakness and knuckling. The dog died on 20 days after presentation. Postmortem examination revealed a mass in the body of thoracic vertebra. Histopathologically, the mass consisted of granulomatous inflammation, including fungal organisms that were immunohistochemically positive for Candida albicans. Similar granulomatous lesions were observed in the systemic lymph nodes, kidneys, pancreas, spleen, prostate gland, thyroid glands and heart. This case was diagnosed as systemic candidiasis with spondylitis.  相似文献   
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Lasiodiplodia theobromae, Thielaviopsis paradoxa, Colletotrichum musae, C. gloeosporioides, Fusarium verticillioides, and F. oxysporum were screened in vitro for sensitivity to Na2CO3, NaHCO3, CaCl2, NaCl, and NaClO. The spore germination of all pathogens was completely inhibited by Na2CO3 4g/l, NaClO 5g/l, and NaHCO3, CaCl2, and NaCl 6g/l each. Dipping the bananas for 10–15min in these concentrations reduced the incidence of crown rot (compared with the untreated fruits) 17 days after harvest in fruits treated with NaClO by 67%, with NaHCO3 by 62%, with NaCl by 38%, and with CaCl2 by 33%. Na2CO3-treated fruits had the same incidence of crown rot as untreated fruits.  相似文献   
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Silicone tubes filled with estradiol‐17β (E2) or the xenestrogen, bisphenol A (BPA) were covered with a polyethylene tube and implanted into mice subcutaneously. The releasing patterns from the tube in vivo were obtained from the volume of estrogen remaining in the tube by measurement with high performance lipid chromatography. E2 in glycerol was released in a few days from a silicone tube, which was not covered with a polyethylene tube (Type A). However, E2 in sesame oil was released very slowly from the silicone tube covered with a polyethylene tube (Type B) and approximately 10% of E2 remained in the tube at 56 days after implantation into the mice. The mean linear regression equation for E2 was Y = 70.967 ? 1.2271X (R2 = 0.9268) and the quadratic regression equation was Y = 77.97 ? 2.2773X + 0.0194 × 2 (R2 = 0.9864). The remainder rate curves of E2 and BPA were not significantly different throughout the experimental period of 56 days. The Type B tube in the present experiment might be useful for long‐term administration of estrogens.  相似文献   
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