What determines the distribution of a flightless bush-cricket (<Emphasis Type="Italic">Metrioptera brachyptera</Emphasis>) in a fragmented landscape?

Based on metapopulation theory, isolation, patch size and habitat quality within patches have recently been identified as the most critical parameters determining the persistence of species. In the special case of flightless and sedentary Orthoptera species, taking into account the low dispersal ability, species survival probably depends more on habitat quality than on isolation. The aim of this study was to document how landscape (patch size, isolation and climate) and microhabitat (vegetation structure, microclimate and land use) factors influence patch occupancy and population densities, respectively, of a flightless bush-cricket (Metrioptera brachyptera) in fragmented calcareous grasslands. In summer 2005 patch occupancy of M. brachyptera was assessed in 68 calcareous grassland patches of the Diemel Valley (central Germany). Among these, 26 patches with 80 plots were selected to characterise M. brachyptera habitats in detail. On each plot, bush-cricket density was sampled in an area of 20 m² using a 0.5 m² box quadrat. At the landscape level (patches) in 46 (68%) of 68 studied calcareous grassland patches M. brachyptera was present. Patch occupancy increased with annual precipitation and patch size but was independent of altitude, annual temperature and isolation. At the microhabitat level (plots), population density of M. brachyptera decreased with land-use intensity and increased with vegetation height. In addition, a high litter accumulation was adverse for M. brachyptera. Given the low explanatory power of isolation for patch occupancy, conservation of flightless and sedentary insects, such as M. brachyptera, should primarily focus on improving habitat quality. For M. brachyptera and other stenotopic calcareous grassland species we therefore recommend traditional rough grazing with sheep, which creates a heterogenous habitat structure and avoids the accumulation of too much litter.     

Production and characteristics of human tissue plasminogen-activator antibodies with region-oriented synthetic peptides.

We selected six peptide sequences as belonging to potential epitopes of tissue plasminogen activator (tPA) using, as the main criterion for their choice, the location of the peptide sequences on the surface of the protein molecule. The six peptides (corresponding to amino acids 4-8, 11-16, 96-101, 272-277, 371-376 and 514-519) were synthesized, coupled to carrier proteins and injected into rabbits. All of these peptides elicited antibodies and 15-75% binding of the corresponding iodinated peptide was obtained with a 1:100 dilution of antiserum. Only two anti-(peptide) sera [anti-(tPA96-101) and anti-(tPA272-277)] reacted with intact tPA and its heavy chain in Western immunoblotting analysis. These two peptides sequences and fragment tPA11-16 appear to be involved in the structure of native antigenic epitopes of tPA, since they were recognized and antibodies present in antisera raised against native tPA. There was no interaction between anti-(tPA4-8) and anti-(tPA371-376) sera with intact one-chain or two-chain tPA. In the case of anti-(tPA4-8) cleavage of one-chain tPA to two-chain tPA and reduction of disulfide bonds exposed this epitope.     

Microhabitat selection in a grassland butterfly: a trade-off between microclimate and food availability

Understanding the factors that determine habitat quality is vital to ensuring appropriate habitat management. The main objective of this study was to assess the microhabitat preferences of egg-depositing females of the Grizzled Skipper (Pyrgus malvae) in calcareous grasslands of the Diemel Valley (Central Germany) for defining habitat quality. Based on this knowledge, we make management recommendations for the conservation of this threatened species. P. malvae generally preferred open and warm oviposition sites. However, there were considerable differences in the environmental conditions, depending on the selected host plant. On the small Potentilla tabernaemontani plants that grew in sparse vegetation with low-growing turf, mostly only one egg was found per plant. In contrast, occupied Agrimonia eupatoria host plants were larger and more prominent, regularly having more than one egg, and grew at sites with a taller and denser vegetation. The observed oviposition pattern reflects a trade-off between microclimate and food availability: Usually, occupied P. tabernaemontani plants grow under favourable microclimatic conditions. However, during hot years the risk of desiccation is high, leading to food shortage. In contrast, A. eupatoria generally provides more biomass, thrives on deeper soils and the vegetation has a cooler microclimate: hence, food shortage is somewhat unlikely. To meet the described habitat requirements of P. malvae, traditional rough grazing by sheep and goats seemed to be the most appropriate land management strategy. The re-introduction of coppicing in woodlands, particularly adjacent to calcareous grasslands, would also be beneficial.     

The peptide beta 43-47 which increases microvascular permeability is released by plasmin during cleavage of fragment Y of fibrinogen

A synthetic pentapeptide corresponding to sequence 43-47 of human fibrinogen B beta chain elicited, in rabbits, antibodies that during immunoblotting recognized intact fibrinogen, fragments X and Y as well as the B beta chain. Since fragment Y is the last peptide product which reacts with anti-beta 43-47 antibodies, splitting of fragment Y into fragment D and fragment E must be accompanied by plasmin cleavage of the peptide bond beta Lys-47-Ala-48.     

The role of macropters during range expansion of a wing-dimorphic insect species

Marked changes in distribution in consequence of global warming have been observed not only for highly mobile insect taxa, which are capable of flight, but also for wing-dimorphic species with predominantly short-winged individuals. In the special case of wing-dimorphic species, it is likely that the rarer long-winged (macropterous) morph plays an important role in the dispersal process, but little is known about how and to what extent it is involved. The aim of our study was to provide more information on the mechanisms behind dispersal processes in wing-dimorphic insects at expanding range margins. As solitary individuals are believed to play an important role in the range expansion of wing-dimorphic species (potential dispersers), we recorded the number of long-winged and short-winged solitary males at the local range margin of our model organism Metrioptera roeselii (Orthoptera: Tettigoniidae) in NW Germany. To investigate differences in dispersal capability (% macropters) between populations with different colonisation histories, we studied 43 populations of M. roeselii. Our results show that about 2/3 of the solitary males were long-winged and these long-winged individuals were significantly more frequent in recently colonised areas. Moreover, M. roeselii had a significantly higher dispersal capability (% macropters) in high-density populations and in recently established populations at the expanding range margin compared to populations characterised by medium- or long-term establishment nearer to the range core. Our study is the first that quantifies the importance of macropters for the recent range expansion of a wing-dimorphic species and it provides for the first time detailed insights into the complex dispersal processes that take place at the expanding range margin. It is likely that density stress and a changed genetic predisposition to become macropterous, and thus a combination of both ecological and evolutionary effects, leads to a high percentage of macropters in recently colonised areas.     

A pilot to examine the logistical and feasibility issues in testing deceased tissue donors for vCJD using tonsil as the analyte

Transplanted tissues have transmitted transmissible spongiform encephalopathies and in the UK there have been more cases of variant Creutzfeldt-Jakob disease (vCJD) than elsewhere in the world. A pilot study was undertaken to look at the feasibility of testing for vCJD in deceased donors using tonsillar tissue. This pilot showed that obtaining consent for removal and testing tonsil tissue was feasible. Donor eligibility for inclusion in the pilot was limited to tissue donors from the National Health Service Blood and Transplant, Tissue Services and to donors shared with the Corneal Transplant Service Eye Banks. Obtaining tonsillar tissue in the immediate post–mortem period was limited by the presence of rigor mortis. Tonsillar tissue was suitable for routine analysis for the presence of prion associated with vCJD in deceased tissue donors. Production and processing of tissue was straightforward and a low assay background was obtained from most samples. Since palatine and lingual tonsil tissue can be obtained in pairs it was possible, in the majority of cases, to set aside an intact sample for confirmatory testing if required. In one instance a sample was reactive by Western blot. However, the pattern of reactivity was not typical for that obtained from vCJD patients. Unfortunately the sample was not of sufficient quality for the confirmatory test to provide a conclusive result.     

Anti-(Arg-Gly-Asp-Ser) antibody and its interaction with fibronectin, fibrinogen and platelets

An antibody population recognizing the sequence Arg-Gly-Asp-Ser (RGDS) in fibronectin, anti-(RGDS)N, was isolated by immunoadsorption. Between 2.5% and 4.9% of antibodies were obtained from two different anti-fibronectin sera indicating that this region represents an antigenic epitope in native fibronectin. Complete inhibition of binding of 125I-fibronectin to anti-(RGDS)N was produced only by nonreduced and reduced fibronectin. Fibrinogen and synthetic RGDS tetrapeptide, each at concentration of 10 microM, showed only a slight inhibition of 22% and 17%, respectively. Measurements of the conformational constant, the equilibrium constant for the interconversion of the non-native and native conformations of this epitope, showed that less than 0.0001% of the RGDS molecules adopt the native conformation in aqueous solutions. It indicates that long-range interactions in fibronectin and fibrinogen result in different conformations of the RGDS sequence in both proteins. Anti-(RGDS)N antibodies purified from anti-fibronectin serum had a strong inhibitory effect on thrombin-stimulated platelet aggregation. They also inhibited binding of fibronectin and fibrinogen to thrombin-stimulated platelets, supporting the primary role of the RGDS sequence in the direct interaction of these proteins with platelet membrane receptors.     

European coding system for tissues and cells: a challenge unmet?

The Comité Européen de Normalisation (European Committee for Standardization, CEN) Workshop on Coding of Information and Traceability of Human Tissues and Cells was established by the Expert Working Group of the Directorate General for Health and Consumer Affairs of the European Commission (DG SANCO) to identify requirements concerning the coding of information and the traceability of human tissues and cells, and propose guidelines and recommendations to permit the implementation of the European Coding system required by the European Tissues and Cells Directive 2004/23/EC (ED). The Workshop included over 70 voluntary participants from tissue, blood and eye banks, national ministries for healthcare, transplant organisations, universities and coding organisations; mainly from Europe with a small number of representatives from professionals in Canada, Australia, USA and Japan. The Workshop commenced in April 2007 and held its final meeting in February 2008. The draft Workshop Agreement went through a public comment phase from 15 December 2007 until 15 January 2008 and the endorsement period ran from 9 April 2008 until 2 May 2008. The endorsed CEN Workshop Agreement (CWA) set out the issues regarding a common coding system, qualitatively assessed what the industry felt was required of a coding system, reviewed coding systems that were put forward as potential European coding systems and established a basic specification for a proposed European coding system for human tissues and cells, based on ISBT 128, and which is compatible with existing systems of donation identification, traceability and nomenclatures, indicating how implementation of that system could be approached. The CWA, and the associated Workshop proposals with recommendations, were finally submitted to the European Commission and to the Committee of Member States that assists its management process under article 29 of the Directive 2004/23/EC on May 25 2008. In 2009 the European Commission initiated an impact assessment on the Workshop proposals and recommendations. In the absence of an agreed pan-European direction various initiatives have continued work using, adopting or adapting their preferred, or existing, methods.