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从云南省会泽县产近无毛灰岩香茶莱〔Rabdosia calcicola (Hand. -Mazz.) Hara var. subculva (Hand. -Mazz.) C. Y. Wu et H. W. Li〕叶中分得两个二萜化合物,一个为新化合物,命名为灰岩香茶菜甲素(calcieolin A),另一个为已知化合物维西香茶菜甲素(weisiensin A),经各项光谱数据和化学反应确定,灰岩香茶菜甲素为3β-羟基-1α,6α,7β,11β-四乙酰氧基-对映-贝壳杉-16-烯-15-酮(1);维西香茶菜甲素结构应为3β,6α-二羟基-1α,7β,11β-三乙酰氧基-对映—贝壳杉-16-烯-15酮(2)。 相似文献
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道孚香茶菜的二萜成分 总被引:1,自引:0,他引:1
从河南省新县产道孚香茶莱[Rabdosia dawoensis(Hand. Mazz.)Hara]叶中分离到两个二萜化合物,根据各种光谱数据推断一个为新化合物,其化学结构为:对映-11α-羟基-3α,6β,7α-一三乙酰氧基-16-贝壳杉烯-15-酮,命名为道孚香茶菜甲素(dowoensin A),另一个为已知化合物信阳冬凌草甲素(xindongnin A). 相似文献
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蓝萼香茶菜化学成分的研究 总被引:25,自引:0,他引:25
从长白山产蓝萼香茶菜[Ralxlosia Japonica(Burm.f.)Hara var.glaucocalyx(Maxim.)Hara]地上全草中分得13个化合物,根据理化常数和波谱学数据分别鉴定为:木栓酮(1)、β-谷淄醇(2)、乙酰熊果酸(3)、齐墩果酸(4)、熊果酸(5)、蓝萼香茶菜素A(6)、2α-羟基熊果酸(7)、2α,3α-二羟基熊果酸(8)、ent-7β,14α,15三羟基-16-贝壳杉烯-3-酮(9)、山香三萜二烯酸(10)、槲皮素(11)、β-谷甾醇3-O-β-D-吡喃葡萄糖苷(12)和果糖(13)。化合物8为第一次从该植物中分得,化合物10为第一次从该属植物中分得。 相似文献
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鲁山冬凌草戊素的结构 总被引:2,自引:0,他引:2
从鲁山冬凌草叶中分得一个新的二萜化合物,鲁山冬凌草戊素(lushanrubesensin E),其结构经各项光谱数据确定为对映-2α,11β-二羟基-3α,6β-二乙酰氧基-16-贝壳杉烯-15-酮。 相似文献
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由采自云南大理苍山的苍山香茶菜[Rabdosia bulleyana(Diels)Hara]叶的乙醚抽提物中,分到一个新的对映-贝壳杉烯型二萜化合物,命名为苍山香茶菜素(bulleya-nin)。根据光谱和化学证据,其化学结构被阐明为对映-12β-羟基-1α,3α,7β,14α-四乙酰氧基-16-贝壳杉烯-15-酮(Ⅰ)(ent-12β-hydroxy-1α,3α,7β,14α-tetraacetoxy-16-Kauren-15-oneⅠ)。收率为生药的0.4%,它对小鼠艾氏腹水癌ECA,小鼠肉瘤S-180,小鼠肝癌腹水均显示较强抑制。 苍山香茶菜素及其衍生物的~1H NMR数据,苍山素和脱氢苍山素的~(13)C NMR 数据已指定。~(13)C NMR的指定是结合应用质子噪声去偶,偏共振去偶和相关化合物的比较。 相似文献
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甘肃产蓝萼香茶菜二萜化学成分研究 总被引:7,自引:0,他引:7
对甘肃天水小陇山产蓝萼香茶菜进行二萜化学成分研究。采用硅胶柱色谱法分离纯化,通过薄层色谱及波谱法进行结构鉴定,SRB法分别对分离化合物进行了体外细胞毒活性测试。共鉴定出5个二萜化合物,它们分别为:1α,6,11β,15β-四乙酰基-6,7-断裂-7,20-内酯-对映-贝壳杉-16-烯(1α,6,11β,15β-tetraacetoy-6,7-seco-7,20-olide-ent-kaur-16-en,Ⅰ),6β,11α-二羟基-6,7-断裂-6,20-环氧-1α,7-内酯-对映-贝壳杉-16-烯-15-酮(6β,11α-di-hydroxy-6,7-seco-6,20-epoxy-1α,7-olide-ent-kaur-16-en-15-one,Ⅱ),6β,7β,14β-三羟基-1α-乙酰氧基-7α,20-环氧-对映-贝壳杉-16烯-15-酮(6β,7β,14β-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one,Ⅲ),6β,11α,15α-三羟基-6,7-断裂-6,20-环氧-1α,7-内酯-对映-贝壳杉-16-烯(6β,11α,15α-trihydroxy-6,7-seco-6,20-epoxy-1α,7-olide-ent-kaur-16-en,Ⅳ),1α,6β,7β,14β-四羟基-7α,20-环氧-对映-贝壳杉-16-烯-15-酮(1α,6β,7β,14β-tetrahydroxy-7α-20-ep-oxy-ent-kaur-16-en-15-one,Ⅴ)。化合物Ⅲ、Ⅳ、Ⅴ均为首次从该植物中分离得到,并且以上5个二萜化合物对人肝癌细胞株Bel-7402和人卵巢癌细胞株HO-8910均显示了良好的细胞毒活性。 相似文献
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紫萼香茶菜甲素的结构 总被引:2,自引:1,他引:1
从紫萼香茶菜叶的乙醚提取物中分得一个新的二萜化合物,命名为紫萼香茶菜甲素(rabdoforrestin A),根据波谱和化学证据,其结构为对映-11β-羟基-2α,3α,6β,7α-四乙酰氧基-16-贝壳杉烯-15-酮(ent-11β-hydroxy-2α,3α,6β,7α-tetraacetoxy-16-kauren-15-one)。另外还分离到已知黄酮化合物线蓟素(cirsilioi 4)。 相似文献
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利用Ad5腺病毒载体系统构建人Sema4C基因重组腺病毒表达载体并在成肌细胞系C2C12中表达,并初步探讨Sema4C基因在成肌发育过程中的可能作用。利用脂质体介导重组腺病毒载体转染HEK293细胞,包装出完整的腺病毒;将重组腺病毒载体感染C2C12成肌细胞后,利用激光共聚焦显微镜观察发现12h即有绿色荧光表达,24h后绿色荧光蛋白表达最强;流式细胞仪检测病毒的感染效率几乎达100%。WB检测结果表明感染重组腺病毒载体组C2C12细胞Sema4C蛋白的表达量明显高于空载体对照组(P<0.01)。为了进一步观察Sema4C基因对C2C12细胞增殖分化的影响,流式细胞仪检测了病毒感染48h后C2C12细胞的增殖指数,并对感染后诱导分化的C2C12细胞的分化情况进行了观察。我们的结果首次表明,过表达外源性人Sema4C基因不仅能使C2C12细胞的G0/G1期比例增加,细胞的增殖指数下降,同时在分化培养条件下还能促进C2C12细胞肌管的形成。 相似文献
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Jűrg Tschopp Eckhard R. Podack 《Biochemical and biophysical research communications》1981,100(3):1409-1414
The lytic property of isolated C9 was shown by using heat (48°C) to induce polymerization of C9, which was then exposed to egg lecithin vesicles containing carboxyfluorescein. In this environment, C9 penetrated the vesicles and released the marker. C5b-9 and C5b-8 also released carboxyfluorescein at 48°C, as did C5b-7 to a lesser extent. However, neither isolated C5b-6, C7, C8 nor albumin caused such release. At 30°C, the C9 remained in the monomeric form and could not lyse the vesicles.C9 polymers formed at 48°C were ring-shaped with an internal diameter of approximately 100 Å and an outer diameter of approximately 180 Å. These rings of C9 polymers strikingly resembled the ultrastructures formed by the membrane attack complex of complement, viewed from the top.Our results indicate that polymeric C9 causes the membranolysis of phospholipid vesicles and, hence, that C9 alone is a cytotoxic molecule. 相似文献
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绵羊Myostatin基因启动子的功能分析 总被引:3,自引:0,他引:3
相比于Myostatin基因的作用机制而言, 对Myostatin基因转录和表达的调控机制了解很少. 为了更好地了解Myostatin基因5’调控区的结构和功能, 深入研究Myostatin基因的转录调控机制, 在最近的研究中克隆了绵羊Myostatin基因的启动子(Pro)序列(GenBank 登录号为AY918121). 进一步以EGFP为报告基因, 构建了各种长度的野生型MSTNProW-EGFP载体和E-box元件突变型MSTNProEM-EGFP载体, 通过转染C2C12小鼠骨骼肌成肌细胞系或绵羊成纤维细胞后, 对各种情况下EGFP的瞬时或稳定表达进行荧光定量分析而比较不同条件下绵羊Myostatin基因启动子的转录调控活性. 结果表明, 0.3~1.2 kb的绵羊Myostatin基因启动子都能不同程度地驱动EGFP在C2C12细胞中的转录和表达, 其中1.2 kb片段的转录调控活性最高. 然 而, 将绵羊1.2 kb MSTNProW-EGFP载体转染绵羊成纤维细胞后并未观察到EGFP的表达, 说明Myostatin基因表达的肌肉特异性源于启动子的转录特异性. 对稳定转染绵羊1.2 kb MSTNProW-EGFP载体的C2C12细胞进行荧光分析, 结果表明细胞生长密度的增加可以反馈性抑制Myostatin基因的转录和表达. 在C2C12分化状态下, 1.2 kb野生型绵羊Myostatin基因启动子的活性比成肌状态时显著升高, 而1.2 kb E(3+5+7)突变型Myostatin基因启动子的活性在C2C12分化前后并未表现出差别. 这一结果暗示肌肉调控因子MyoD可能是通过与E-box结合而引起Myostatin基因在C2C12分化和生长状态时转录和表达差异的一个原因. 相似文献
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报道中国海产刚毛藻科(Cladophoraceae),沙生刚毛藻Cladophora arenaria,蝾螺刚毛藻C. conchopheria,暗色刚毛藻C. opaca,透明刚毛藻C. pellucida,微小刚毛藻C. pusilla,棉形刚毛藻C. rudolphiana,光毛刚毛藻C. sericea,美丽刚毛藻C. speciosa。 相似文献
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eterachopsis was proposed by the senior author as an independent genus of
the family Aspleniaceae in 1940 with 2 species. Since then much study on its morphology, anatomy, gametophyte and palynology has been carried out by Nayar, Bir, Chandra & Nayar and Chang et al., and they are of the opinion that the genus like Ceterach,
is a comparatively primitive element in the family Aspleniaceae. The queer zigzag patern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae,
and also suggests its antiquity in evolution. So far only 3 species (C. dalhousiae, C.
paucivenosa and C. magnifica) are recognized, the former from W. Himalayas, also
known from Africa, while the latter two from W. S. China (Yunnan). However, in
the past forty years the Chinese botanists have discovered 2 more species as new in N.
W. Yunnan, thus bringing the total known species of the genus up to 5. The present
paper is a brief summary on the genus Ceterachopsis, which will be published in detail
in the Flora Sinica vol. 4.
Pteridologists are also divided in their views regarding the generic status of Ceterachopsis with 5 well-defined species in Yunnan and the East Himalayas. We prefer
to mintain it as a genus separate from Asplenium on account of its distinct morphological features. It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way. 相似文献
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Activation of protein kinase C by a tumor-promoting phorbol ester in pancreatic islets 总被引:2,自引:0,他引:2
Rat pancreatic islet homogenates display protein kinase C activity. This phospholipid-dependent and calcium-sensitive enzyme is activated by diacylglycerol or the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). In the presence of TPA, the Ka for Ca2+ is close to 5 microM. TPA does not affect phosphoinositide turnover but stimulates [32P]- and [3H]choline-labelling of phosphatidylcholine in intact islets. Exogenous phospholipase C stimulates insulin release, in a sustained and glucose-independent fashion. The secretory response to phospholipase C persists in media deprived of CaCl2. It is proposed that protein kinase C participates in the coupling of stimulus recognition to insulin release evoked by TPA, phospholipase C and, possibly, those secretatogues causing phosphoinositide breakdown in pancreatic islets. 相似文献
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从武夷山和张家界自然保护区发现三虫草新种,武夷山虫草Cordyceps wuyishanensis, 张家界虫草Cordyceps zhangjiajiensis和拟茂兰虫草Cordyceps maolanoides。武夷山虫草和其近缘种的主要区别是,可孕部分柱状、非多年生、子囊孢子不断裂和间细胞长达6~10祄。张家界虫草与其近缘种相比较的鉴别特征为非木质化的较小子座、子囊壳表生和具有较长的(15~23祄)次生子囊孢子。拟茂兰虫草和近缘种茂兰虫草C.maolanoides的形态特征相近,其主要差别是前者的子座和子囊壳都小得多。报道了玫烟色拟青霉Paecilomyces fumosoroseus与蜣螂虫草Cordyceps geotrupis 有密切关系。研究标本保存于贵州大学真菌资源研究室(LFRGU)。 相似文献