大肠癌筛查新策略及研究进展

大肠癌是全世界最常见的恶性肿瘤之一,由于其发病率和死亡率较高严重影响了人类健康。由于大肠癌的发病是缓慢渐进的,早期进行有效的筛查可以延长患者的寿命及改善其生活质量并达到预防和治疗的目的。近几年,随着分子生物学及基因组学的不断发展,出现了许多新的筛查方法,这为大肠癌的防治提供了更多的机会,也给患者及其家庭带来了生命的曙光。目前国内外对大肠癌筛查新方法相关方面的研究尚不多,综述也较少。现就近几年国内外大肠癌的一些筛查新策略及研究进展综述如下。     

假单胞菌脂肪酶的研究进展

脂肪酶是一种重要的工业用酶,来自于假单胞菌的脂肪酶较来自其它菌株的具有更强的温度、有机溶剂耐受性等比较优势,在有机合成、食品工业、药物制造、油脂深加工等工业应用方面应用潜力巨大。对假单胞菌脂肪酶的分类及性质、结构、表达调控和分泌机制等进行了简要的概述。     

Possibilities for agroforestry development in Bulgaria: Outlooks and limitations

Current conditions in Bulgaria are favorable for the development of agroforestry due to socio-economic incentives and environmental necessities. As a scientific theory and practice, agroforestry is less familiar than other farming systems in Bulgaria. Hence, to ensure successful agroforestry development in Bulgaria, four necessary movements (or collective national ‘moments’) are described here: (1) wide-scale popularization of agroforesty's fundamental tenets, including its nature as a production system, types of agroforestry systems, structural components, methods for design, construction, maintenance and management, advantages and disadvantages and possible applications in Bulgaria; (2) a comprehensive research program on agroforestry, in areas such as high-tech selection of plant and animal species suitable for agroforestry technologies (including cultivation of lesser-known indigenous species that may be better suited to local conditions), studies of how to balance the biophysical interactions of agroforestry species to optimize and conserve natural recourses (e.g., sunlight, soil, water, microclimate), knowledge of best cultural practices (e.g., fertilization, irrigation, IPM) and economic analyses of various agroforestry systems; (3) education and preparation of interdisciplinary specialists for the development of this new economic direction; (4) realization of government policies to enhance and encourage the development of agroforestry in ways that are economically appropriate for the nation. These policies should include long-term development strategies, national and regional program plans and structures, financial incentives (loans, subsidies, tax reductions, ensuring production sales, awards, etc.) and establishment of agroforestry demonstration sites.     

中国科学院古脊椎动物与古人类研究所成立暨北京猿人第一个头盖骨发现65周年庆典在京举行

中国科学院古脊椎动物与古人类研究所成立暨北京猿人第一个头盖骨发现６５周年庆典在京举行１９９４年是北京猿人第一个头盖骨发现６５周年,也是古脊椎动物与古人类所的前身──中国地质调查所新生代研究室成立６５周年;更重要的是古脊椎所几代人盼望已久并为之做出不懈...     

Stimulation of hepatic glycogenolysis by 12-O-tetradecanoylphorbol-13-acetate (TPA) via a calcium requiring process

12-O-Tetradecanoylphorbol-13-acetate (TPA) stimulated glycogenolysis in perfused rat liver which was perfused with Krebs-Ringer-bicarbonate buffer containing 1 mM CaCl2 but no substrate. Verapamil (100 microM), diltiazem (100 microM) and trifluoperazin (100 microM), all inhibited the effect of TPA in the presence of CaCl2. Omission of CaCl2 from the perfusate or the addition of EGTA markedly attenuated the effect of TPA. TPA decreased net release of 45Ca from 45Ca-preloaded liver. The effect of maximal concentration of TPA (20 ng/ml) was not additive to that of 0.6 microM A23187. These data suggest that TPA increases calcium influx into hepatocytes and stimulates glycogenolysis through a calcium-calmodulin dependent mechanism.     

人类疾病遗传易感性研究方法进展

遗传易感性是指基于个人遗传背景的多基因遗传病发病风险,即来源于父母一方或双方的特定遗传变异在某些情况下会诱发疾病。在特定疾病的发病机制中某些高外显率的遗传变异发挥重要作用,此类疾病通过患病家系分析即可定位疾病相关遗传变异;但另一些低外显率变异的作用则不明显,需要大规模患病人群分析来解析遗传机制。近年来,随着二代测序和多组学分析技术的发展和基因组数据的大量积累,癌症、代谢性疾病、心脑血管疾病和精神疾病等疾病遗传易感性研究中取得了显著进展,为疾病的早期筛查和诊断治疗提供了参考。     

Structural characterization of lichenysin A components by fast atom bombardment tandem mass spectrometry

The structural characterization of the cyclic lipoheptapeptide surfactant lichenysin A components, produced by Bacillus licheniformis strains via the non-ribosomal pathway on a corresponding peptide synthetase, was carried out using a tandem mass spectrometry (MS/MS) under fast atom bombardment (FAB) conditions. Based on the analysis of the collision-induced fragment-ion spectrum of the single charged molecular ions of both native and partially hydrolyzed forms of lipopeptide, a new general structure of lichenysin A components was elucidated. It varies from previously proposed structure by having in the peptide portion of lipopeptide the l-Gln-1 and l-Asp-5 residues instead of l-Glu-1 and l-Asn-5. The verified chemical structure of lichenysin A was found to be reflected in the structural organization of the corresponding lichenysin A synthetase, LchA, described recently.