New avenues for phage-display library to produce a Cryptococcus-specific anti-idiotypic antibody of HM-1 killer toxin

Existing antifungal drugs are notable for their inability to act rapidly, as well as their toxicity and limited spectrum. The identification of fungal-specific genes and virulence factors would provide targets for new and influential drugs. The display of repertories of antibody fragments on the surface of filamentous phage offers a new way to produce immunoreagents as defined specificities. Here we report the selection of Cryptococcus-specific targets by using phage-display panning from a cDNA library, where bactericidal antibodies have been developed against conserved surface-exposed antigens. A single-chain variable fragment (scFv) phage library was constructed from splenocyte of an immunized mouse by idiotypic vaccination with HM-1 killer toxin (HM-1) neutralizing monoclonal antibody (nmAb-KT) that was used for selection against Cryptococcus neoformans membrane fraction (CnMF). Key elements were the selection against antigen (nmAb-KT and CnMF) and the release of bound phages using competitive panning elution with CnMF at neutral pH condition. Isolated scFvs react specifically with C. neoformans and some other pathogenic and non-pathogenic fungal strain's cell wall receptors by exerting strong antifungal activity in vitro. A high affinity clone, designated M1 was selected for detailed characterization and tested anti-cryptococcal activity with IC(50) values at 5.33 × 10(-7) to 5.56 × 10(-7) M against C. neoformans. The method described here is a new technique for the isolation of cell membrane specific immunoreactive phages in the form of scFv using CnMF that contained cell membrane associated proteins.     

Climate change threatens European conservation areas

Europe has the world's most extensive network of conservation areas. Conservation areas are selected without taking into account the effects of climate change. How effectively would such areas conserve biodiversity under climate change? We assess the effectiveness of protected areas and the Natura 2000 network in conserving a large proportion of European plant and terrestrial vertebrate species under climate change. We found that by 2080, 58?±?2.6% of the species would lose suitable climate in protected areas, whereas losses affected 63?±?2.1% of the species of European concern occurring in Natura 2000 areas. Protected areas are expected to retain climatic suitability for species better than unprotected areas (P?相似文献   

Pharmacological modulation of NMDA receptor activity and the advent of negative and positive allosteric modulators

The NMDA receptor (NMDAR) family of l-glutamate receptors are well known to have diverse roles in CNS function as well as in various neuropathological and psychiatric conditions. Until recently, the types of agents available to pharmacologically regulate NMDAR function have been quite limited in terms of mechanism of action and subtype selectivity. This has changed significantly in the past two years. The purpose of this review is to summarize the many drug classes now available for modulating NMDAR activity. Previously, this included competitive antagonists at the l-glutamate and glycine binding sites, high and low affinity channel blockers, and GluN2B-selective N-terminal domain binding site antagonists. More recently, we and others have identified new classes of NMDAR agents that are either positive or negative allosteric modulators (PAMs and NAMs, respectively). These compounds include the pan potentiator UBP646, the GluN2A-selective potentiator/GluN2C and GluN2D inhibitor UBP512, the GluN2D-selective potentiator UBP551, the GluN2C/GluN2D-selective potentiator CIQ as well as the new NMDAR-NAMs such as the pan-inhibitor UBP618, the GluN2C/GluN2D-selective inhibitor QZN46 and the GluN2A inhibitors UBP608 and TCN201. These new agents do not bind within the l-glutamate or glycine binding sites, the ion channel pore or the N-terminal regulatory domain. Collectively, these new allosteric modulators appear to be acting at multiple novel sites on the NMDAR complex. Importantly, these agents display improved subtype-selectivity and as NMDAR PAMs and NAMs, they represent a new generation of potential NMDAR therapeutics.     

Diagnosis of complex coastal ecological systems: Environmental GIS analysis of a highly stressed Mediterranean lagoon through spatiotemporal indicators

This article explores the need for implementing spatiotemporal criteria in environmental planning of special protected areas, applying the analysis of reaction patterns in the case study of the Mar Menor, a Mediterranean coastal lagoon in South-Eastern Spain. To perform this, the Mar Menor environmental patterns suffering traditionally from intense coastal urbanization, and in recent years from important eutrophication problems, will be analyzed from an integrated approach and retrospectively assessed through territorial indicators. The evaluation will provide a clear example of a protected area regulated by multiple European Natura 2000 figures of protection that nevertheless is suffering from a strong and varied anthropic process over time. The results will show that paradoxically this process sometimes has little territorial linkage origin with the area concerned. This aspect will be addressed by using GIS indicators, to present the real correlation between coastal urbanization and agricultural land transformation with Mar Menor evolution over time (in which it is pointed out that the weight of the latter is much greater than the former) and how far it is necessary to establish an area of influence of the environmental impacts by proposing a new scope of application for the resolution of the current situation of eutrophication in its waters.     

A Relevance Index for the habitat areas of Natura 2000 Network based on their Rarity and Representativeness

The 231 habitat types included in the European Environmental Agency (EEA) database of the Natura 2000 Network are distributed throughout more than 22 thousand Sites of Community Importance (SCI) covering around 128 million hectares in Europe. However, individual habitat areas have different conservation relevance according to the Rarity of the habitat type and their Representativeness in relation to the whole type.We propose a Relevance Index and evaluate it for each area of each habitat type, taking into account the Rarity of the habitat type, assessed by the extent of its occurrence in the Natura 2000 Network, and the Representativeness of the area, as the contribution of that area to the total extent of that habitat type in the Network.Results allow for an objective analysis of the Natura 2000 Network indicating, for example, that rarity of a habitat type in Natura 2000 Network does not necessarily correlate with its priority status, suggesting the need for reevaluation of the situation.The Relevance Index proposed for a given habitat area is the product of the Rarity Index of its habitat type and the Representativeness of the area. We demonstrate the application of the Index for the areas of three different Natura 2000 Sites. The Relevance Index of one Site (SRI) will be the sum of the Relevance Indices of its corresponding habitat areas (HRI). The same approach is applicable to regions, countries or for any habitat cluster allowing for the quantification of their contribution to the whole Natura 2000 Network.It is suggested that the Relevance index can also be applied in monitoring the components of the Natura 2000 Network, and is useful to support management decisions for conservation in Europe.     

Origin of the First Cells on Earth: A Possible Scenario

A fundamental challenge in science is to understand the assembly of the first macromolecules necessary for cellular life and the order in which this occurred. The assembly events that led to the first minimal cell capable of growth and division are a highly debatable subject. Possibly, the formation of a primitive membrane or microsphere in a hydrophobic medium provided a suitable structure where subsequent biochemical self-replication and eventually enzyme catalysis, integrated biochemical pathways, and assembly of nucleic acids occurred. In this article, I examine a possible sequence of assembly for the first primitive cell(s) on the Earth.     

Climate effects on the distribution of wetland habitats and connectivity in networks of migratory waterbirds

The establishment and maintenance of conservation areas are among the most common measures to mitigate the loss of biodiversity. However, recent advances in conservation biology have challenged the reliability of such areas to cope with variation in climate conditions. Climate change can reshuffle the geographic distribution of species, but in many cases suitable habitats become scarce or unavailable, limiting the ability to migrate or adapt in response to modified environments. In this respect, the extent to which existing protected areas are able to compensate changes in habitat conditions to ensure the persistence of species still remains unclear. We used a spatially explicit model to measure the effects of climate change on the potential distribution of wetland habitats and connectivity of Natura 2000 sites in Italy. The effects of climate change were measured on the potential for water accumulation in a given site, as a surrogate measure for the persistence of aquatic ecosystems and their associated migratory waterbirds. Climate impacts followed a geographic trend, changing the distribution of suitable habitats for migrants and highlighting a latitudinal threshold beyond which the connectivity reaches a sudden collapse. Our findings show the relative poor reliability of most sites in dealing with changing habitat conditions and ensure the long-term connectivity, with possible consequences for the persistence of species. Although alterations of climate suitability and habitat destruction could impact critical areas for migratory waterbirds, more research is needed to evaluate all possible long-term effects on the connectivity of migratory networks.     

Probing the steric barrier of nonionic surfactant vesicles with melittin

The role of the surface polymer brush of nonionic surfactant vesicles (NSV) in inhibiting interactions with small membrane-perturbing molecules was investigated using the bee venom peptide melittin as a probe. The interaction between melittin and NSV was compared with that of distearoylphosphatidylcholine (DSPC) vesicles and sterically stabilised liposomes (SSL) containing 5 mol% pegylated distearoylphosphatidylethanolamine (DSPE.E₄₄). The degree of melittin interaction with the various vesicles was determined by measuring peptide binding and folding, using intrinsic tryptophan fluorescence and circular dichroism respectively, in addition to monitoring the release of encapsulated carboxyfluorescein dye. NSV composed of 1,2-di-O-octadecyl-rac-glyceryl-3-(ω-dodecaethylene glycol) (2C₁₈E₁₂) showed a strong affinity for melittin, whilst exhibiting ~ 50% less bound peptide than SSL. 2C₁₈E₁₂:Chol vesicles showed reduced melittin interaction, in a manner consistent with Chol incorporation into DSPC vesicles. These results are discussed with respect to the effect of Chol on the in-plane order of 2C₁₈E₁₂ bilayers and consequent attenuation of hydrophobic interactions with the peptide. NSV formed from equimolar mixtures of polyoxyethylene-n-stearoyl ethers C₁₈E₂ and C₁₈E₂₀ showed a greater interaction with melittin than 2C₁₈E₁₂. However, replacing C₁₈E₂₀ with C₁₈E₁₀ was sufficient to achieve an attenuation of melittin interaction similar to that observed in 2C₁₈E₁₂:Chol vesicles. This indicates that the presence of surface polymer brush alone may confer resistance to melittin, provided hydrophobic interactions between the peptide and the vesicles can be minimised, through improved in-plane bilayer order.     

Functional traits of woody plants: correspondence of species rankings between field adults and laboratory‐grown seedlings?

Abstract. Research into interspecific variation in functional traits is important for our understanding of trade‐offs in plant design and function, for plant functional type classifications and for understanding ecosystem responses to shifts in species composition. Interspecific rankings of functional traits are a function of, among other factors, ontogenetic or allometric development and environmental effects on phenotypes. For woody plants, which attain large size and long lives, these factors might have strong effects on interspecific trait rankings. This paper is the first to test and compare the correspondence of interspecific rankings between laboratory grown seedlings and field grown adult plants for a wide range of functional leaf and stem traits. It employs data for 90 diverse woody and semiwoody species in a temperate British and a (sub)Mediterranean Spanish flora, all collected according to a strict protocol. For 12 out of 14 leaf and stem traits we found significant correlations between the species ranking in laboratory seedlings and field adults. For leaf size and maximum stem vessel diameter > 50 % of variation in field adults was explained by that in laboratory seedlings. Two important determinants of plant and ecosystem functioning, specific leaf area and leaf N content, had only 27 to 36 and 17 to 31 % of variation, respectively, in field adults explained by laboratory seedlings, owing to subsets of species with particular ecologies deviating from the general trend. In contrast, interspecific rankings for the same traits were strongly correlated between populations of field adults on different geological substrata. Extrapolation of interspecific trait rankings from laboratory seedlings to adult plants in the field, or vice versa, should be done with great caution.