Ascochlorin inhibits growth factor-induced HIF-1α activation and tumor-angiogenesis through the suppression of EGFR/ERK/p70S6K signaling pathway in human cervical carcinoma cells

Ascochlorin, a non-toxic prenylphenol compound derived from the fungus Ascochyta viciae, has been shown recently to have anti-cancer effects on various human cancer cells. However, the precise molecular mechanism of this anti-cancer activity remains to be elucidated. Here, we investigated the effects of ascochlorin on hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression in human epidermoid cervical carcinoma CaSki cells. Ascochlorin inhibited epidermal growth factor (EGF)-induced HIF-1α and VEGF expression through multiple potential mechanisms. First, ascochlorin selectively inhibited HIF-1α expression in response to EGF stimulation, but not in response to hypoxia (1% O(2)) or treatment with a transition metal (CoCl(2)). Second, ascochlorin inhibited EGF-induced ERK-1/2 activation but not AKT activation, both of which play essential roles in EGF-induced HIF-1α protein synthesis. Targeted inhibition of epidermal growth factor receptor (EGFR) expression using an EGFR-specific small interfering RNA (siRNA) diminished HIF-1α expression, which suggested that ascochlorin inhibits HIF-1α expression through suppression of EGFR activation. Finally, we showed that ascochlorin functionally abrogates in vivo tumor angiogenesis induced by EGF in a Matrigel plug assay. Our data suggest that ascochlorin inhibits EGF-mediated induction of HIF-1α expression in CaSki cells, providing a potentially new avenue of development of anti-cancer drugs that target tumor angiogenesis.     

斜带石斑鱼经葡萄糖灌喂后的代谢反应

糖类的主要生理功能是为动物机体提供能量,而且是比蛋白质和脂肪更为廉价的能源。相对于陆生恒温动物,鱼类尤其是肉食性鱼类对糖的利用能力低下,似乎先天性地具有糖尿病患者的某些生理特征。饲料中过高的糖水平会导致鱼类抗病力下降、生长速度减缓、死亡率增加等症状。鱼类解除葡萄糖负荷的能力有限从而表现     

国产悬钩子属绢毛亚组新资料

报道了采自西藏墨脱县悬钩子属绢毛亚组Rubus subsect.Lineati (Focke) Yü et Lu两个中国新纪录种,即酒红悬钩子R.calophyllus Clarke.和炫丽悬钩子R splendidissimus Hara.     

The long-distance migration of Nilaparvata lugens (Stål) (Delphacidae) in China: radar observations of mass return flight in the autumn

Abstract.

• 1 A case study is presented of the autumn migration of the brown planthopper, Nilaparvata lugens (Stål), in the area of Nanjing in the People's Republic of China. The study was made using a high frequency (8 mm wavelength) radar and a net suspended from a kytoon.
• 2 The observations confirmed that long-distance return migrations occur in China in mid and late September, with N.lugens being carried on the prevailing north-easterly wind towards the autumn infestation and overwintering areas of the species.
• 3 After mass take-off in the late afternoon or at dusk, the migrants flew for several hours during the evening, often in a dense layer which formed at heights between about 400 and 1000m above ground. These layers often had well-defined ceilings corresponding to an air temperature of about 16°C. The migration height was above the top of the surface temperature inversion, i.e. the migrants did not fly at the height of the warmest air.
• 4 The dense layer concentrations overflying the radar were backtracked to source areas up to 240 km away in the north-east of Jiangsu Province. Planthoppers observed emigrating from the Nanjing area would reach areas in south Anhui Province or north Jiangxi Province if they flew for 12 h.
• 5 There was a second period of mass take-off at dawn. Insect layers sometimes formed but did not last longer than 1–2h.
• 6 The present results were strikingly different from those previously observed in the dry season in the Philippines, where migratory flight durations were largely confined to periods of about 30min at dusk and dawn.
• 7 Our observations are discussed in relation to the equator-wards return migrations undertaken in autumn by other insect species, and the importance of these migrations for the maintenance of long-flying genotypes in the overwintering populations is considered.

     

红细胞抗高血压因子降压作用的进一步研究

我们曾报道原发性高血压患者(EHS)红细胞抗高血压因子(AHF)具有缓慢而持久的降压作用。本工作表明,AHF对卒中易感型自发性高血压大鼠(SHRsp)还具有快速短暂的降压作用,注射AHF后10—30s,SHRsp收缩压从原水平的26.8±1.7kPa降至20.1±1.5kPa(P<0.001)。正常人和大鼠红细胞AHF的降压作用明显强于EHS和高血压大鼠AHF。此外我们还发现EHS血浆中存在升压物质。以上结果提示,AHF缺乏和升压物质含量相对较高可能是原发性高血压发病的一个重要原因。     

蝴蝶兰组培快繁及热激处理抑制褐变的研究

以9个蝴蝶兰品种的花梗和无菌苗叶片为试材,研究了不同品种间不定芽诱导率及增殖系数的差异,并选出增殖系数高、中、低的3个代表性品种‘内山姑娘’、‘梦幻兄弟’和‘万花筒’,对不定芽增殖条件进行优化,并对培养过程中褐变严重的品种‘内山姑娘’进行了热激处理抑制褐变的研究。结果表明:(1)相同条件下,不同蝴蝶兰品种间不定芽诱导率和增殖(分化)系数存在显著差异,且花梗芽诱导率和繁殖系数高的品种,其叶片的不定芽诱导率和分化系数也较高。(2)6-BA是影响蝴蝶兰不定芽增殖的主要因素,椰汁次之。培养基1/2MS+7.0mg.L-16-BA+0.2mg.L-1 NAA+100mL.L-1椰汁适于‘内山姑娘’和‘梦幻兄弟’品种的不定芽增殖,1/2MS+5.0mg.L-1 6-BA+0.2mg.L-1 NAA+50mL.L-1椰汁适合‘万花筒’品种的不定芽增殖。(3)40℃热激处理9min恢复48h后再切割接种能够显著减轻蝴蝶兰‘内山姑娘’叶片的褐变程度,热激处理后叶片组培过程中的褐变指数、总酚含量以及苯丙氨酸解氨酶(PAL)活性均显著低于对照,且三者的两两之间均具有极显著正相关关系,证明短时间的热激处理可降低酚合成酶PAL的活性,减少酚类化合物的积累,从而减轻组培过程中的褐变伤害。     

布氏杆菌脑膜炎病例报道2例及文献复习

目的:目前布氏杆菌性脑膜炎在国内只是偶见报道,本文报道2例布氏杆菌性脑膜炎,对其诊断及治疗进行探讨,并对布氏杆菌脑膜炎进行文献回顾.方法:我们近期连续通过检查脑脊液内布氏杆菌抗体的办法诊断了2例布氏杆菌性脑膜炎,并通过给予四环素、利福霉素及链霉素治疗1个月并通过随访.结果:半年后脑脊液内布氏杆菌抗体恢复阴性,临床症状完全消失.结论:通过我们的观察应用上述3联药物综合治疗1月对布氏杆菌性脑膜炎是有效的.     

不同降水条件下科尔沁沙地南缘疏林草地樟子松针叶δ13C和叶性状特征

通过比较不同自然降水年份(极端干旱和极端湿润)19年生疏林草地樟子松的针叶δ¹³C、比叶面积和干物质含量,结合土壤含水量和地下水埋深,探讨了极端降水对樟子松水分利用的影响.结果表明: 干旱年份(2009)樟子松林土壤含水量显著低于湿润年份(2010),但樟子松当年生针叶的δ¹³C在两年间没有显著差异,且两年相同月份间亦无显著差异;干旱年份当年生针叶的比叶面积显著低于湿润年份,而不同年份间干物质含量的差异不显著.在两种极端降水条件下,樟子松的水分利用效率没有明显变化,主要通过改变当年生针叶的比叶面积来适应降水量的变化.对于地下水埋深高于3.0 m的疏林草地樟子松人工林生态系统,极端干旱不会严重影响樟子松的存活和生长.     

带鱼下脚料水解物对大鼠血管内皮损伤的影响

通过检测带鱼下脚料蛋白酶水解物的药理作用,为带鱼下脚料的开发利用提供理论依据。用带鱼下脚料三酶混合水解物喂养盐酸肾上腺素造成血管内皮损伤模型的大鼠,检测大鼠血清中血管内皮生长因子(VEGF)和血管性血友病因子(vWF)的含量变化。结果表明:实验不给药组与空白对照组及实验给药组相比,VEGF和vWF的含量存在显著差异。注射盐酸肾上腺素成功制造了血管内皮损伤模型,带鱼下脚料蛋白酶水解物对内皮损伤没有显著影响,但对损伤后的内皮修复有明显的促进作用。     

不同芥酸含量油菜品系FAD2基因克隆测序分析

对高芥酸品系M136、0Coγ辐照得到的高芥酸油菜突变体H27和低芥酸品系742的FAD2基因克隆并测序。结果发现,FAD2基因存在两个拷贝FAD2.1(1155bp)、FAD2.2(1140bp)。H27的FAD2.1与M13序列相同,但FAD2.2核苷酸序列中M13在409位点A(腺嘌呤)变成了T(鸟嘌呤),导致密码子由AGA变换为TGA(终止密码子),使H27中的FAD2.2基因的功能丧失,这可能是芥酸含量的提高原因。