基于CiteSpace分析核酸适体（Aptamer）技术研究现状

利用可视化分析软件,客观、全面地展示和分析适体的研究现状、研究热点和发展趋势,为适体的研究提供指导和参考。以SCI数据库Web of Science平台为数据源,采用CiteSpace 5.5.R2软件对1900年1月1日至2020年12月31日的适体相关文献进行分析。共纳入文献14 939篇。在该领域发表论文最多的作者是WEIHONG TAN、KHALIL ABNOUS等;近年来突现的主题词是“wide linear range”“pg ml”“clinical diagnosis”“early diagnosis”等,是目前该领域的研究热点;作者共被引分析和文献共被引分析表明,该领域的研究主要集中在适体的体外筛选、适体构象的变化、适体在药物靶向治疗中的应用及适体生物传感器。结果表明,利用CiteSpace软件对Web of Science数据库中已发表的适体文献进行分析,揭示了该领域的研究热点从体外筛选和适体构象变化（1992—2002）到适体在药物靶向治疗和适体生物传感器中的应用（2002—2020）。结合近年来突现的主题词预测适体在药物靶向治疗和适体生物传感器中的应用仍将是未来的研究热点。     

Plasma Homocysteine Is Associated with Aortic Arterial Stiffness but not Wave Reflection in Chinese Hypertensive Subjects

Objective

Elevated plasma total homocysteine (tHcy) acts synergistically with hypertension to exert a multiplicative effect on cardiovascular diseases risk. The aim of this study was to determine the relationship between tHcy concentration and blood pressure, and to evaluate the role of plasma tHcy in arterial stiffness and wave reflection in hypertension.

Methods

In this cross-sectional study, a community-based sample of 1680 subjects (mean age 61.6 years) was classified into four groups according to tHcy level (<21.6 vs. ≥21.6 µmol/l) and blood pressure (hypertensive vs. normotensive). Levels of plasma tHcy and other biochemical parameters (e.g., lipids, glucose) were determined. Central arterial blood pressure, reflected pressure wave, and carotid-femoral pulse wave velocity (cf-PWV) were assessed by tonometry within 2 days of obtaining the blood specimen.

Results

Neither peripheral nor central blood pressure differed according to tHcy levels in normotensive and hypertensive subjects. Differences in cf-PWV according to tHcy were observed only in hypertensive subjects; differences in cf-PWV in normotensive subjects were not significant after adjusting for confounding factors. Central augmentation index did not differ according to tHcy level in either normotensive or hypertensive subjects. Results of univariate analysis revealed significant correlations between blood pressure parameters and tHcy concentration only among normotensive subjects; however, these correlations were not significant in a partial correlation analysis. Results of multiple regression analysis showed that plasma tHcy levels were independently correlated with cf-PWV in hypertensive subjects (β = 0.713, P = 0.004). The independent relationship between tHcy and central augmentation index was not significant by further multiple analyses in normotensive or hypertensive individuals.

Conclusions

Plasma tHcy level is strongly and independently correlated with arterial stiffness measured as cf-PWV only in hypertensive subjects. Thus, hypertension is a major link between tHcy and aortic arterial stiffness.     

干热处理法对人免疫球蛋白某些特性的影响

人免疫球蛋白制品以蔗糖为热稳定剂经６０℃８０小时和７２℃８０小时干热处理后理化性质的改变结果表明,６０℃８０小时干热处理后ＩｇＧ各成份相对含量,重新溶解后外观等结果与干热处理前基本相同,经选择不同种类糖作热稳定剂比较,以７－８％蔗糖浓度稳定效果较好     

长期围封对疏勒河源区高寒草甸地表节肢动物多样性的影响

围封会促进退化高寒草甸植被和土壤环境恢复,长期围封也会导致生物多样性及其功能下降,影响高寒草甸生态系统的稳定,但这种影响会随着季节和生境条件变化而异。为了探究不同退化程度高寒草甸地表节肢动物群落变化对围封禁牧的响应,利用陷阱法调查了疏勒河源区沼泽化草甸、草甸和草原化草甸3种不同退化梯度高寒草甸围封禁牧和自由放牧处理下地表节肢动物群落结构变化。结果表明：围封禁牧对高寒草甸地表节肢动物群落组成及多样性的影响随生境条件不同而异。禁牧降低了沼泽化草甸地表节肢动物的物种丰富度,而提高了草甸和草原化草甸地表节肢动物的物种丰富度;围封禁牧对沼泽化草甸地表节肢动物群落结构影响较小,显著降低了草甸生境地表节肢动物活动密度、提高了地表节肢动物多样性和均匀度,相反,禁牧显著提高了草原化草甸生境地表节肢动物活动密度、降低其多样性和均匀度;豹蛛属1种是高寒草甸主要的地表节肢动物类群（相对多度为67.0%）,高寒草甸土壤水分有效性等生境条件不同影响了豹蛛属1种对围封禁牧的响应模式,进而影响了地表节肢动物群落结构变化。总之,高寒草甸退化程度影响了地表节肢动物多样性对禁牧和放牧的响应模式,沼泽化草甸适度放牧有利于提高地表节肢动物多样性及其功能。     

Association of lipid metabolism-related gene promoter methylation with risk of coronary artery disease

Molecular Biology Reports - Coronary artery disease (CAD) is a complex disease that is influenced by environmental and genetic factors. Lipid levels are regarded as a major risk factor for CAD, and...     

Population study of atmospheric bacteria at the Fengtai district of Beijing on two representative days

Summary We collected bacteria from the atmosphere (5–6 m above ground level) with an Andersen microbial sampler at Fengtai District, Beijing, in the spring and autumn of 1989. The 195 strains of bacteria collected and isolated were identified according to their morphological, biochemical and physiological characteristics. The results showed that there were 11 bacterial genera in the atmosphere of the town, the most abundant beingStaphylococcus andBacillus. The order of prevailing genera of the two seasons is similar. In morphology, gram positive (G⁺) bacteria predominate among atmospheric bacteria (G⁺ cocci, G⁺ rods and G⁺ endospore-forming rods). It seems that the constitution of atmospheric bacteria is influenced not only by the source strength of the various bacteria in the environment, but also by their somewhat resistant mechanisms such as protective pigments and spore structure. From our experience, in order to avoid the possible data loss from selecting and identifying some «representative» colonies of samples, all strains isolated should be identified when studying ecological distribution of microbes in the atmosphere.     

RcMYBPA2 of Rosa chinensis functions in proanthocyanidin biosynthesis and enhances abiotic stress tolerance in transgenic tobacco

Plant Cell, Tissue and Organ Culture (PCTOC) - Proanthocyanidins (PAs) are major antioxidant flavonoids that play a key role in protecting plants against adverse environmental stress, but the...