As-built design specification for Boundary Detection And Registration Program (BDARP1)

There are no author-identified significant results in this report

Mutant and chimeric recobinant plasminogen activatorsproduction in eukaryotic cellsand preliminary characterization

Mutant urokinase-type plasminogen activator (u-PA) genes and hybrid genes between tissue-type plasminogen activator (t-PA) and u-PA have been designed to direct the synthesis of new plasminogen activators and to investigate the structure-function relationship in these molecules. The following classes of constructs were made starting from cDNA encoding human t-PA or u-PA: 1) u-PA mutants in which the Arg156 and Lys158 were substituted with threonine, thus preventing cleavage by thrombin and plasmin; 2) hybrid molecules in which the NH2-terminal regions of t-PA (amino acid residues 1-67, 1-262, or 1-313) were fused with the COOH-terminal region of u-PA (amino acids 136-411, 139-411, or 195-411, respectively); and 3) a hybrid molecule in which the second kringle of t-PA (amino acids 173-262) was inserted between amino acids 130 and 139 of u-PA. In all cases but one, the recombinant proteins, produced by transfected eukaryotic cells, were efficiently secreted in the culture medium. The translation products have been tested for their ability to activate plasminogen after in situ binding to an insolubilized monoclonal antibody directed against urokinase. All recombinant enzymes were shown to be active, except those in which Lys158 of u-PA was substituted with threonine. Recombination of structural regions derived from t-PA, such as the finger, the kringle 2, or most of the A-chain sequences, with the protease part or the complete u-PA molecule did not impair the catalytic activity of the hybrid polypeptides. This observation supports the hypothesis that structural domains in t-PA and u-PA fold independently from one to another

Vapor phase infiltration for transforming polymers into organic-inorganic hybrid materials: Processing science, structural complexity, and emerging applications

Vapor phase infiltration (VPI) exposes polymers to gaseous metalorganic molecules that sorb, diffuse, and become entrapped in the bulk polymer, transforming it into a complex organic-inorganic hybrid material.1 This process is pictured in Figure 1. While VPI’s gaseous dosing sequences may appear similar to other vapor deposition techniques (e.g., atomic layer deposition) the set of atomic scale processes occurring during synthesis constitute a fundamentally different process that results in not just a simple coating on the polymer but rather a complete alteration of the polymer’s bulk chemistry. Please click Additional Files below to see the full abstract

Simplification of Caribbean Reef-Fish Assemblages over Decades of Coral Reef Degradation

Caribbean coral reefs are becoming structurally simpler, largely due to human impacts. The consequences of this trend for reef-associated communities are currently unclear, but expected to be profound. Here, we assess whether changes in fish assemblages have been non-random over several decades of declining reef structure. More specifically, we predicted that species that depend exclusively on coral reef habitat (i.e., habitat specialists) should be at a disadvantage compared to those that use a broader array of habitats (i.e., habitat generalists). Analysing 3727 abundance trends of 161 Caribbean reef-fishes, surveyed between 1980 and 2006, we found that the trends of habitat-generalists and habitat-specialists differed markedly. The abundance of specialists started to decline in the mid-1980s, reaching a low of ~60% of the 1980 baseline by the mid-1990s. Both the average and the variation in abundance of specialists have increased since the early 2000s, although the average is still well below the baseline level of 1980. This modest recovery occurred despite no clear evidence of a regional recovery in coral reef habitat quality in the Caribbean during the 2000s. In contrast, the abundance of generalist fishes remained relatively stable over the same three decades. Few specialist species are fished, thus their population declines are most likely linked to habitat degradation. These results mirror the observed trends of replacement of specialists by generalists, observed in terrestrial taxa across the globe. A significant challenge that arises from our findings is now to investigate if, and how, such community-level changes in fish populations affect ecosystem function

Prior specification in Bayesian occupancy modelling improves analysis of species occurrence data

Multi-species biodiversity indicators are increasingly used to assess progress towards the 2020 ‘Aichi’ targets of the Convention on Biological Diversity. However, most multi-species indicators are biased towards a few well-studied taxa for which suitable abundance data are available. Consequently, many taxonomic groups are poorly represented in current measures of biodiversity change, particularly invertebrates. Alternative data sources, including opportunistic occurrence data, when analysed appropriately, can provide robust estimates of occurrence over time and increase the taxonomic coverage of such measures of population change. Occupancy modelling has been shown to produce robust estimates of species occurrence and trends through time. So far, this approach has concentrated on well-recorded taxa and performs poorly where recording intensity is low. Here, we show that the use of weakly informative priors in a Bayesian occupancy model framework greatly improves the precision of occurrence estimates associated with current model formulations when analysing low-intensity occurrence data, although estimated trends can be sensitive to the choice of prior when data are extremely sparse at either end of the recording period. Specifically, three variations of a Bayesian occupancy model, each with a different focus on information sharing among years, were compared using British ant data from the Bees, Wasps and Ants Recording Society and tested in a simulation experiment. Overall, the random walk model, which allows the sharing of information between the current and previous year, showed improved precision and low bias when estimating species occurrence and trends. The use of the model formulation described here will enable a greater range of datasets to be analysed, covering more taxa, which will significantly increase taxonomic representation of measures of biodiversity change

A cost effective RFLP method to genotype Solute carrier organic anion 1B1 (SLCO1B1) c.1929A>C (p.Leu643Phe, rs34671512); a variant with potential effect on rosuvastatin pharmacokinetics

Objective: This study describes a restriction fragment polymorphism protocol for rapidly screening the polymorphism SLCO1B1 c.1929A>C in genomic DNA samples. The polymorphism SLCO1B1 c.1929A>C has been associated with increased activity resulting in increased hepatic uptake of drugs. Currently SLCO1B1 c.1929A>C is genotyped using direct sequencing techniques and 5′ nuclease based assays which can be cost prohibiting in resource limited settings. The aim of this study therefore was to design and validate a cost effective RFLP for genotyping the SLCO1B1 c.1929A>C polymorphism. This study was designed to investigate the effect of the polymorphism SLCO1B1 c.1929A>C on interindividual variability in rosuvastatin pharmacokinetics in healthy volunteers of African descent. Results We describe a restriction fragment length polymorphism method to genotype SLCO1B1 c.1929A>C polymorphism using the restriction enzyme Ase1. A student’s t test with Welch correction was used to establish association between the SLCO1B1 c.1929A>C variant and rosuvastatin exposure. The frequency of the SLCO1B1 c.1929C allele amongst Zimbabweans was 6%. The SLCO1B1 c.1929C allele was associated with a 75% reduction (P C may therefore play a significant role in rosuvastatin response. The RFLP method is quick and cost effective

Temporal correlations in population trends: Conservation implications from time-series analysis of diverse animal taxa

Population trends play a large role in species risk assessments and conservation planning, and species are often considered threatened if their recent rate of decline meets certain thresholds, regardless how large the population is. But how reliable an indicator of extinction risk is a single estimate of population trend? Given the integral role this decline-based approach has played in setting conservation priorities, it is surprising that it has undergone little empirical scrutiny. We compile an extensive global dataset of time series of abundance data for over 1300 vertebrate populations to provide the first major test of the predictability of population growth rates in nature. We divided each time series into assessment and response periods and examined the correlation between growth rates in the two time periods. In birds, population declines tended to be followed by further declines, but mammals, salmon, and other bony fishes showed the opposite pattern: past declines were associated with subsequent population increases, and vice versa. Furthermore, in these taxa subsequent growth rates were higher when initial declines were more severe. These patterns agreed with data simulated under a null model for a dynamically stable population experiencing density dependence. However, this type of result could also occur if conservation actions positively affected the population following initial declines—a scenario that our data were too limited to rigorously evaluate. This ambiguity emphasizes the importance of understanding the underlying causes of population trajectories in drawing inferences about rates of decline in abundance

Bleeding time prolongation and bleeding during infusion of recombinant tissue-type plasminogen activator in dogs: Potentiation by aspirin and reversal with aprotinin

AbstractThrombolytic therapy is associated with a bleeding tendency that may be exacerbated by adjunctive antiplatelet agents. The effect of recombinant tissue-type plasminogen activator (rt-PA) alone or in combination with aspirin on serial measurements of template bleeding time, ex vivo platelet aggregation and coagulation factors and the frequency of bleeding was studied in dogs. During infusion of rt-PA (15, 30 or 60 μg/kg per min for 90 min), a dose-related increase in bleeding tine was observed.In a randomized blinded study of 25 dogs, the baseline bleeding time (mean ± SD) was 3.5 ± 1 min in control animals and 4 ± 2 min after oral aspirin (15 mg/kg body weight). Infusion of rt-PA (15 μg/kg per min for 90 min) prolonged the bleeding time to a maximum of 15 ± 12 min. In contrast, combined aspirin and rt-PA therapy produced an increase to >30 min during infusion, reverting to 13 ± 10 min within 2 h after cessation of infusion. Recurrent continuous bleeding from incision sites occurred in one of six dogs given aspirin alone, two of seven given rt-PA alone and all six dogs given both aspirin and rt-PA (p = 0.02). Bleeding time >9 min correlated significantly with bleeding frequency (p < 0.0001), with a sensitivity of 100% and a specificity of 87%.Intravenous bolus injection of aprotinin (29,000 kallikrein inhibitor units/kg body weight) in six dogs given both rt-PA and aspirin produced a decrease in bleeding time from >30 min to 9.5 ± 9 min and resulted in cessation of bleeding. Thus, bleeding and bleeding time prolongation te this canine model are potentiated by a marked interactive effect of rt-PA and aspirin that is rapidly reversible. Template bleeding times may provide a useful quantitative index for monitoring the bleeding tendency associated with thrombolytic therapy