Nomenclature systems for the neuroprostanes and for the neurofurans

The isolation of two new classes of human docosahexaenoic acid oxidation products, the neuroprostanes and the neurofurans, have been reported. Facile nomenclature systems that will allow the rational differentiation of each of the isomeric structures comprising the families of NeuroP's and NeuroF's, represented, respectively, by 17-F(4t)-NeuroP 1 and 10-epi-ST-Delta(15)-11-NeuroF 2 are presented.     

The future for plants and plants for the future

A report of the 2007 EMBO Conference Series on Plant Molecular Biology 'From basic genomics to systems biology', Ghent, Belgium, 2-4 May 2007.     

Molecular signatures for the Crenarchaeota and the Thaumarchaeota

Crenarchaeotes found in mesophilic marine environments were recently placed into a new phylum of Archaea called the Thaumarchaeota. However, very few molecular characteristics of this new phylum are currently known which can be used to distinguish them from the Crenarchaeota. In addition, their relationships to deep-branching archaeal lineages are unclear. We report here detailed analyses of protein sequences from Crenarchaeota and Thaumarchaeota that have identified many conserved signature indels (CSIs) and signature proteins (SPs) (i.e., proteins for which all significant blast hits are from these groups) that are specific for these archaeal groups. Of the identified signatures 6 CSIs and 13 SPs are specific for the Crenarchaeota phylum; 6 CSIs and >250 SPs are uniquely found in various Thaumarchaeota (viz. Cenarchaeum symbiosum, Nitrosopumilus maritimus and a number of uncultured marine crenarchaeotes) and 3 CSIs and ~10 SPs are found in both Thaumarchaeota and Crenarchaeota species. Some of the molecular signatures are also present in Korarchaeum cryptofilum, which forms the independent phylum Korarchaeota. Although some of these molecular signatures suggest a distant shared ancestry between Thaumarchaeota and Crenarchaeota, our identification of large numbers of Thaumarchaeota-specific proteins and their deep branching between the Crenarchaeota and Euryarchaeota phyla in phylogenetic trees shows that they are distinct from both Crenarchaeota and Euryarchaeota in both genetic and phylogenetic terms. These observations support the placement of marine mesophilic archaea into the separate phylum Thaumarchaeota. Additionally, many CSIs and SPs have been found that are specific for different orders within Crenarchaeota (viz. Sulfolobales—3 CSIs and 169 SPs, Thermoproteales—5 CSIs and 25 SPs, Desulfurococcales—4 SPs, and Sulfolobales and Desulfurococcales—2 CSIs and 18 SPs). The signatures described here provide novel means for distinguishing the Crenarchaeota and the Thaumarchaeota and for the classification of related and novel species in different environments. Functional studies on these signature proteins could lead to discovery of novel biochemical properties that are unique to these groups of archaea.     

Evidence for linkage between the locus for the AB0-system and the locus for phosphoglucoseisomerase (PGI)

Summary The investigation of 2 families with 9 informative siblings seems to give some evidence for linkage between the structural loci for AB0 and PGI. The recombination frequency is 1/9 or 0.1.Supported by the Deutsche Forschungsgemeinschaft.     

Evidence for the spatial separation of the binding sites for substrate and for cytoskeletal proteins on the enzyme aldolase

The effect of the proteolysis of aldolase on both the substrate specificity of the enzyme and binding capacity for actin have been studied. Carboxypeptidase A, trypsin, chymotrypsin and pepsin, all acted to cleave peptides from the C-terminal portion of the enzyme, resulting initially in a marked loss of activity towards fructose-1:6-bisphosphate (FBP), without impairment of activity towards fructose-1-phosphate (F1P). In some cases, however, further proteolysis caused reductions in activity with F1P as well. By correlating the size of the peptide fragments released by these enzymes with the known sequence of aldolase, evidence has been provided that cleavage of His-359 and/or Tyr-361 lead to the loss of FBP activity, while further cleavage of up to six amino acids begin to affect activity against F1P, as well. In regard to the ability of the proteolysed aldolase to bind to F-actin, it was evident from these studies that binding ability was not impaired in the initial stages of proteolysis referred to above, but was retained until the enzyme was extensively degraded. This differential behaviour of the active and binding sites on aldolase clearly establish their separate topographical localization. These results have been discussed in relation to the positioning of these separate sites on the enzyme, the nature of the interaction between aldolase and actin and the phenomenon of enzyme ambiquity in cells and tissues.     

Plants for Food and Medicine: Proceedings of the Joint Conference of the Society for Economic Botany and the International Society for Ethnopharmacology

Plants for Food and Medicine: Proceedings of the Joint Conference of the Society for Economic Botany and the International Society for Ethnopharmacology. H. D. V. Prendergast. N. L. Etkin. D. R. Harris. and P. J. Houghton. eds. Kew, Richmond, UK: Scientific Publications Dept., Royal Botanic Gardens, 1998. 438 pp.     

The case for the hybrid capital approach for the measurement of the welfare and sustainability

This paper provides an overview of the plethora of approaches that are available to measure welfare and sustainable development. Many methods exist but there is no consensus on the ‘correct’ approach. Furthermore, we also show that the wide variety of sustainable development indictor (SDI) sets which have been adopted also show significant differences. We argue that this is mostly because many of these studies do not use a theoretical approach. We argue that the ‘capital approach’, which is used in the sustainability debate, is the most promising method to enhance international harmonization. Support is mounting in the scientific, policy and statistical communities for this approach in which economic capital, human capital, natural capital and social capital are distinguished. Many applications of this method express these capital stocks in monetary units (the ‘monetary capital approach’). This paper argues that the ‘hybrid capital approach’, in which the capital stocks can also be measured in non-monetary units, is probably more likely to achieve consensus over a large number of countries and institutes. Also a number of challenges remain for the capital approach. We argue that ideally the indicators should be based on satellite accounts of the national accounting framework. Also the capital approach could be further expanded to current welfare, progress of societies, inequality, and the international dimension of sustainability. We conclude that if the hybrid capital approach is adopted it may become easier to make consistent, theoretically sound and policy relevant comparisons between countries.     

Scientific basis for the Soviet and Russian radiofrequency standards for the general public

The former Soviet Union (USSR) and the USA were the first countries to introduce standards limiting exposure to radiofrequency (RF) fields. However, the exposure limits in the USSR standards were always much lower than those in the USA and other countries. The objective of this article is to provide a history of the development of the Soviet and Russian RF standards. In addition, we summarize the scientific evidence used to develop the original USSR RF and subsequent Russian public health standards, as well as the mobile telecommunications standard published in 2003, but we do not critique them. We also describe the protective approaches used by the Soviet and Russian scientists for setting their limits. A translation of the papers of the key studies used to develop their standards is available in the online version of this publication. Bioelectromagnetics 33:623–633, 2012. © 2012 Wiley Periodicals, Inc.     

检验医学专业临床实习管理存在的问题及对策

临床实习是医学理论和临床实践工作有机结合的连接点,是医学生走向临床工作必不可少的重要环节。临床实习教学是医学生教育中一个重要的组成部分,是从课堂到临床、从理论到实践、从理性到感性的重要过程,也是巩固基础知识、理论联系实际、走向独立工作岗位的重要一步。在临床实践过程中,教职人员要培养学生获取、分析和处理疾病信息的能力,正确书写病历、熟练掌握诊疗技术以及与患者及家属和谐沟通的能力。医学检验学是运用现代物理化学方法、手段进行医学诊断的一门学科,通俗的说,就是利用仪器、试剂、CT扫描等检测人的各项指标是否正常,为临床诊断提供依据。因此,加强临床检验医学专业的实习管理工作至关重要。本文从建立合理的教学管理体系、加强临床实习考核制度、完善实习管理、加强教师队伍建设等几个方面,探讨临床检验学实习管理存在的问题,并提出相应的对策,为高等医学院校教学管理工作提供思路。     

Kinetic and thermodynamic parameters for tRNA binding to the ribosome and for the translocation reaction.

Kinetic analyses of tRNA binding to the ribosome and of the translocation reaction showed the following results. 1) The activation energy for the P site binding of AcPhe-tRNA to poly(U)-programmed ribosomes is relatively high (Ea = 72 kJ mol-1; 15 mM Mg2+). If only the P site is occupied with deacylated tRNA(Phe), then the E site can be filled more easily with tRNA(Phe) (no activation energy measurable) than the A site with AcPhe-tRNA (Ea = 47 kJ mol-1; 15 mM Mg2+). 2) A ribosome with blocked P and E sites represents a standard state of the elongation cycle, in contrast to a ribosome with only a filled P site. The two states differ in that AcPhe-tRNA binding to the A site of a ribosome with prefilled P and E sites requires much higher activation energy (87 versus 47 kJ mol-1). The latter reaction simulates the allosteric transition from the post- to the pretranslocational state, whereby the tRNA(Phe) is released from the E site upon occupation of the A site (Rheinberger, H.-J., and Nierhaus, K. H. (1986) J. Biol. Chem. 261, 9133-9139). The reversed transition from the pre- to the posttranslocational state (translocation reaction) requires about the same activation energy (90 kJ mol-1). 3) Both elongation factors EF-Tu and EF-G drastically reduce the respective activation energies. 4) The rate of the A site occupation is slower than the rate of translocation in the presence of the respective elongation factors. The data suggest that the A site occupation rather than, as generally assumed, the translocation reaction is the rate-limiting step of the elongation cycle.     

Tools and Materials for the Crafts

A brief examination of early childhood music education in South Africa, through an investigation of government documents and academic literature, leads to an impression that music is embraced in a broad framework of meeting young children's cultural and artistic needs. There is an overriding consciousness of the value of providing children with connections to their cultural heritage and instilling in them appreciation for one another's cultures and respect for diversity. More specific policy for each age level of early childhood in several governmental departments is needed to protect children's voices and to ensure not only that their musical heritage and artistic creativity are nourished and fostered but also that we listen to what they say through their music.     

Homochirality and the Need for Energy

The mechanisms for explaining how a stable asymmetric chemical system can be formed from a symmetric chemical system, in the absence of any asymmetric influence other than statistical fluctuations, have been developed during the last decades, focusing on the non-linear kinetic aspects. Besides the absolute necessity of self-amplification processes, the importance of energetic aspects is often underestimated. Going down to the most fundamental aspects, the distinction between a single object—that can be intrinsically asymmetric—and a collection of objects—whose racemic state is the more stable one—must be emphasized. A system of strongly interacting objects can be described as one single object retaining its individuality and a single asymmetry; weakly or non-interacting objects keep their own individuality, and are prone to racemize towards the equilibrium state. In the presence of energy fluxes, systems can be maintained in an asymmetric non-equilibrium steady-state. Such dynamical systems can retain their asymmetry for times longer than their racemization time.