PCR—SSCP技术及其在植物研究中的应用

简单介绍了PCR—SSCP技术的原理、方法、特点,并阐述了其在植物研究中的应用及发展前景。     

生态足迹模型的争论与发展

生态足迹模型自William Rees1992年提出、Mathis Wackemagel 1996年推广应用以来,在众多研究者的质疑和争论中不断发展、完善。目前,国内已有许多综述文章详细介绍了其理论假设、基本概念、计算方法、实证应用、一些缺陷改进等。在这些综述成果基础上,结合近2～3年的研究新进展,概括了10a来对其理论假设、均衡因子、产量因子、计算方法、过于静态性、缺乏预测性、结论单一性等方面存在的主要争论,聚焦了在概念发展、计算方法、均衡因子、产量因子、应用领域、时间序列、非线性科学研究方法、与其他社会经济指标相结合等方面进行的改进及发展,并指出今后生态足迹模型研究将要在计算方法改进、加强实践操作及市场化运作、与可持续发展政策的有机联系、与非线性科学研究方法相结合、长时间序列动态评估、单项指标等方面取得重要进展。这些争论、改进的综述及发展方向的提出,目的在于引发国内对生态足迹模型研究的新思考,推动生态足迹模型理论的进一步完善和发展。     

Development of the hand and wrist bones in chimpanzees

Skeletal developmental of chimpanzees was studied cross-sectionally. By application of the TW2 method, we described the skeletal development of chimpanzees and compared their skeletal development with humans'. A development pattern of chimpanzees repeated accelerations and decelerations displaying “early-juvenile trough,” “pre-adolescent peak,” “mid-adolescent trough,” and “post-adolescent peak” in incremental curves. Sex differences in skeletal development are slower development in males during infant and early juvenile phases, and greater increment around the adolescent phase in males. Females are fully mature at younger ages than males, e.g. about one and a half years. In comparison with chimpanzees, humans have such characteristics as a longer slower period of juvenile development and a shorter spurt-like adolescent fast period which ends with full maturity.     

Polymorphisms of interferon-inducible genes OAS-1 and MxA associated with SARS in the Vietnamese population

We hypothesized that host antiviral genes induced by type I interferons might affect the natural course of severe acute respiratory syndrome (SARS). We analyzed single nucleotide polymorphisms (SNPs) of 2',5'-oligoadenylate synthetase 1 (OAS-1), myxovirus resistance-A (MxA), and double-stranded RNA-dependent protein kinase in 44 Vietnamese SARS patients with 103 controls. The G-allele of non-synonymous A/G SNP in exon 3 of OAS-1 gene showed association with SARS (p=0.0090). The G-allele in exon 3 of OAS-1 and the one in exon 6 were in strong linkage disequilibrium and both of them were associated with SARS infection. The GG genotype and G-allele of G/T SNP at position -88 in the MxA gene promoter were found more frequently in hypoxemic group than in non-hypoxemic group of SARS (p=0.0195). Our findings suggest that polymorphisms of two IFN-inducible genes OAS-1 and MxA might affect susceptibility to the disease and progression of SARS at each level.     

Angiotensin-converting enzyme insertion/deletion polymorphism and risk of myocardial infarction in an updated meta-analysis based on 34 993 participants

The association between angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphism and risk of myocardial infarction (MI) has been extensively studied. However, the results were in controversy. This study aimed to explore the association between ACE I/D polymorphism and risk of MI by using a meta-analysis. We retrieved the following databases to indentify eligible studies: Medline, Embase, ISI, VIP, CBM and Wan Fang database. The latest update was 10th May, 2012. Odds ratio and 95% confidence interval (95% CI) were used to present the strength of the association. A total of 40 case–control studies with 34 993 participants were included. Overall, D allele of ACE I/D polymorphism was significantly associated with an increased risk of MI in genetic comparison models (OR (95% CI): 1.41 (1.22–1.64) for DD vs. II; 1.11 (1.01–1.21) for ID vs. II; 1.23 (1.10–1.37) for D carriers vs. II; 1.28 (1.15–1.43) for DD vs. I carriers and 1.06 (1.02–1.10) for D carriers vs. I carriers). Subgroup analyses, according to ethnicities and countries of participants also indicated that D allele was significantly associated with an increased risk of MI in Asians (especially for Chinese) and Caucasians (especially for English, French, Germans and Italians) (OR (95% CI) of DD vs. ID + II: 2.11 (1.65–2.70) for Asians and 1.15 (1.05–1.27) for Caucasians). In conclusion, this meta-analysis indicated that D allele of ACE I/D polymorphism was a possible risk factor for MI incidence for both Asians and Caucasians.     

高等植物激素受体的研究进展

高等植物体内的新陈代谢和生长发育主要受遗传信息及环境间的相互调节,细胞间通讯系统的主要信号分子就是植物激素.高等植物有别于动物在于其难以逃避或改变环境,因而适应多变环境来维持生存是主要的途径,而细胞间的通讯系统便是高等植物与环境适应的必不可少的重要桥梁和纽带.近年来,高等植物激素受体及信号系统的研究取得了许多进展,而且其激素受体研究的系统理论已经形成.结合本研究室部分工作及国内外进展及成果对本领域工作进行系统归纳并评述其发展方面存在的问题及前景.     

Enhanced ozone exposure of European beech (Fagus sylvatica) stimulates nitrogen mobilization from leaf litter and nitrogen accumulation in the soil

Abstract

In a lysimeter study with young beech trees, the effects of elevated ozone concentration on the decomposition and fate of nitrogen in ¹⁵N‐labeled leaf litter were analyzed after one growing season. Nitrogen in the litter was dominated by a relatively inert, residual fraction, but easily decomposable nitrogen was present in substantial amounts. Nitrogen loss was significantly higher at twice‐ambient ozone which was largely attributed to an enhanced mobilization of residual nitrogen. Enhanced mobilization of nitrogen from litter at twice‐ambient ozone exposure resulted in additional ¹⁵N incorporation into the soil down to 30 cm depth. Only 0.41–0.62% of the nitrogen in the litter was incorporated into plant material at both ozone concentrations. Twice‐ambient ozone exposure changed the distribution of the nitrogen taken up from litter inside the beech trees in favor of the shoot, where it may have been used in biosynthetic processes required for defense reactions.     

Ionic liquid-enabled synthesis,cholinesterase inhibitory activity,and molecular docking study of highly functionalized tetrasubstituted pyrrolidines

A small library of novel spiropyrrolidine heterocyclic hybrids has been prepared regioselectively in 1-butyl-3-methylimidazoliumbromide ([bmim]Br) with good to excellent yields using a [3+2] cycloaddition reaction. These synthesized compounds were evaluated as potential agents for treating Alzheimer’s disease. Compound 4b showed the most potent activity, with an IC₅₀ of 7.9 ± 0.25 µM against acetylcholinesterase (AChE). The inhibition mechanisms for the most active compounds on AChE and butyrylcholinesterase (BChE) receptors were elucidated using molecular docking simulations.