生态系统健康研究进展

健康的生态系统一般被视为环境管理的终极目标,进行生态系统健康研究对探索区域与生态系统可持续发展具有重要意义。随着国际生态与健康学会(International Association for Ecology and Health)的解体,生态系统健康研究视角出现转型。系统梳理了近年来国际上有关生态系统健康概念及其评估方法、指标的新进展,通过文献统计和重要文献引用揭示了国际生态系统健康研究的发展历程,提出了从生态系统健康到生态健康再到生态文化健康的三大核心框架发展阶段,生态系统健康的研究对象和范围正在不断扩充。资源环境研究领域是国内研究者应用生态系统健康概念与方法的优势领域,在区域尺度上评价生态系统的健康更贴近资源环境和社会文化交互作用的复合表征理念。因此,我国生态系统健康研究的趋向不仅应包括在生态系统尺度上研究的继续深化,也应包含对生态文化健康概念的完善与应用,并发挥地理-生态视角的区域集成研究优势,从而有效指导区域生态与环境政策制定与实施。     

21世纪酶工程研究的新动向

概述了21世纪国际上酶工程研究的新进展和新趋势,着重介绍国际酶工程研究领域的“若干热点”和前沿课题,包括基因工程和蛋白质工程的应用,人工合成酶的模拟酶,核酸酶和抗体酶,分子酶学,功能酶学,酶的定向固定化技术,杂交酶,分子发动机,酶化学技术,非水酶学,糖生物学和糖基转移酶,酶标药物,端粒酶,极端环境微生物和不可培养微生物的新酶种,酶在环境保护方面的应用等。     

Chitin and its derivatives: New trends of applied research

The applications of chitin, chitosan and a number of their chemical and natural derivatives, proposed in very recent publications and patents (1977–1980) are reviewed in various fields, including fibre and film manufacture, as paper additives, in metal ion recovery, as semi-synthetic polymers, flocculants, fungicides and a number of aspects of biochemistry. A major trend in chitin applied research is towards more sophisticated applications dealing with immunochemistry, medical aids, enzyme immobilisation and membrane technology. Chitin, therefore, represents an important renewable resource.     

Future trends in pain research

In the future we shall need to modify the classical view that nerve impulses which signal the presence of injury are reliably transmitted by specified and automatic relay cells. We must investigate at least four different modifying mechanisms that are likely to generate chronic intractable pains. With a latency of milliseconds, combinations of afferent signals and of descending controls operate a rapid and powerful gate control. With a latency of minutes, impulses in C fibres change the excitability of peripheral endings and of spinal cord circuits. With a latency of days, chemical transport in C fibres from areas of damage further modifies cord connectivity with a disappearance of inhibitions and an expansion of receptive fields. With a latency of weeks and months, anatomical degeneration produces secondary changes in deafferented cells with atrophy, sprouting and abnormal firing patterns.     

Evolving research trends in bioinformatics

The cross-disciplinary nature of bioinformatics entails co-evolution with other biomedical disciplines, whereby some bioinformatics applications become popular in certain disciplines and, in turn, these disciplines influence the focus of future bioinformatics development efforts. We observe here that the growth of computational approaches within various biomedical disciplines is not merely a reflection of a general extended usage of computers and the Internet, but due to the production of useful bioinformatics databases and methods for the rest of the biomedical scientific community. We have used the abstracts stored both in the MEDLINE database of biomedical literature and in NIH-funded project grants, to quantify two effects. First, we examine the biomedical literature as a whole and find that the use of computational methods has become increasingly prevalent across biomedical disciplines over the past three decades, while use of databases and the Internet have been rapidly increasing over the past decade. Second, we study the recent trends in the use of bioinformatics topics. We observe that molecular sequence databases are a widely adopted contribution in biomedicine from the field of bioinformatics, and that microarray analysis is one of the major new topics engaged by the bioinformatics community. Via this analysis, we were able to identify areas of rapid growth in the use of informatics to aid in curriculum planning, development of computational infrastructure and strategies for workforce education and funding.     

Future trends in nitrogen research

N research effort has undergone major changes over recent decades with changing emphasis because of environmental problems and issues. This driving force, coupled with a universal desire to improve N-use efficiency, appreciation of the importance of maintaining soil resource quality and a need to provide integrated landscape managements, will continue to prompt new research areas and issues for study. Already, much information has been provided and new approaches and needs defined. It will be essential in future research to take full note of the many interactions that occur and to provide a mechanistic basis so that scaling of effects can be undertaken with the appropriate simplification without being superficial. Examples of interactions, as well as fundamental gaps in the basic processes are discussed and needs for future research identified.     

New ganglioside analogs that inhibit influenze virus sialidase

Synthetic thioglycoside-analogs of gangliosides such as Neu5Ac)2-S-6)Glc-(1-1)Ceramide (1) and the GM3 analog Neu5Ac(2-S-6)Gal-(1–4)Glc(1-1)Ceramide (2), competitively inhibited GM3 hydrolysis by the sialidase of different subtypes of human and animal influenza viruses with an apparent K_i value of 2.8×10^–6 and 1.5×10^–5 M, respectively. The inhibitory activity of the ganglioside GM4 analog [Neu5Ac-(2-S-6)Gal-(1-1)Ceramide (3)], in which the glucose of 1 was substituted by galactose, was lower than that of 1 (K_i =1.0×10^–4 M). The thioglycoside-analogs (1, 2, 3) of the gangliosides were nonhydrolyzable substrates for influenza virus sialidase. The inhibitory activity of 1 to bacterial sialidases fromClostridium perfringens andArthrobacter ureafaciens was considerably lower than that to influenza virus sialidase, indicating that the structure of the active site in bacterial and influenza virus sialidase may be different and the analogs may be useful to determine the orientation of the substrate to the active site of sialidases, especially of influenza viruses.Abbreviations Cer ceramide - GM3 Neu5Ac(2–3)Gal(1–4)Glc(1-1)Cer - GM4 Neu5Ac(2–3)Gal(1-1)Cer Gangliosides were abbreviated according to Svennerholm [1] and the recommendation of the IUPAC-IUB Commission on Biochemical Nomenclature [2].     

New trends in CLL treatment

We review here results obtained from the various treatment modalities that have been used in CLL patients: chemotherapy; radiotherapy; splenectomy; leukapheresis; monoclonal antibodies and other immunomodulating agents. We conclude that it is still unclear whether patients in stage A (good prognosis) should be treated; intermediate forms of the disease (stage B) should, in most cases, be treated, but a better treatment than chlorambucil has not emerged; results from the Cooperative Group on CLL of Société Fran?aise d'Hématologie indicate that significant progress in the therapy of the advanced stage (stage C) has been achieved with the introduction of the CHOP regimen, using low doses of adriamycin; radiotherapy, splenectomy and immunomodulators such as levamizol, interleukins or interferons, and possibly monoclonal antibodies, are now being actively tested; the results are not yet conclusive.     

New trends in microbial technology

Microbial technology includes not only the production of materials in bioreactors, or the production of new catalysts by genetic engineering but extends to aspects of both human and animal health care, waste and pollution management, enhanced oil recovery, mineral leaching, advanced plant breeding, diagnostics and analytical equipment, biosensors, bioelectronics and renewable energy system based on biomass feedstocks. National strategies of industrialized countries are being developed which identify microbial technology as a substantial factor in the attainment of industrial and economic goals. Although extremely promising microbial technology is not a quick fix and its application will only arise as a result of systematic programme of research and development. Such programme requires a broad base of disciplinary underpinning in molecular biology, genetics and bioengineering. The development of expertise of this kind in the tertiary educational institutions is the essential starting point. It should be developed by appropriate programmes and networking systems.