The glycoprotein IIb/IIIa antagonist c7E3 inhibits platelet aggregation in the presence of heparin-associated antibodies

AbstractPurpose: Heparin-associated antibodies (HAAb), in the presence of heparin, can cause platelet activation and aggregation. The purpose of this study was to assess whether a platelet glycoprotein (GP) IIb/IIIa receptor antagonist, c7E3, would inhibit platelet aggregation in the presence of HAAb. If aggregation is inhibited by c7E3, enzyme-linked immunosorbent assays (ELISA) would be done to determine whether c7E3 interfered with the binding of heparin and the HAAb.Methods: HAAb-positive plasmas from 21 patients (determined by platelet aggregation assays) were studied. Normal donor platelet-rich plasmas (PRP) were incubated (1 minute) with either saline solution or 3 μg/ml of c7E3. Platelet-poor plasma from patients with HAAb and one of three sources of heparin (25 μl, 10 U/ml; porcine heparin, bovine heparin, and low molecular weight heparin [enoxaparin]) were added to the PRP mixture. Aggregation was determined using a platelet aggregometer by measuring time to aggregation, the slope of the aggregation curve, and the percent change in optical density.Results: Platelet aggregation occured in 100%, 100%, and 95% of the saline solution incubations exposed to porcine heparin, bovine heparin, and enoxaparin, respectively. Incubation with c7E3 caused 100% inhibition of platelet aggregation in plasma exposed to porcine heparin, bovine heparin, and enoxaparin. The optical density curves obtained from the ELISA, which were dependent on the binding of HAAb to heparin, were not significantly different when c7E3 was compared to buffer alone.Conclusions: The GP IIb/IIIa receptor antagonist, c7E3, inhibits HAAb-induced platelet aggregation via a mechanism that does not appear to interfere with the binding between heparin and HAAb. Clinical trials are warranted to assess whether GP IIb/IIIa antagonists may allow patients with HAAb to safely receive heparin. (J Vasc Surg 1997;25:124-30.

Continuous Uniform Finite Time Stabilization of Planar Controllable Systems

Continuous homogeneous controllers are utilized in a full state feedback setting for the uniform finite time stabilization of a perturbed double integrator in the presence of uniformly decaying piecewise continuous disturbances. Semiglobal strong $\mathcal{C}^1$ Lyapunov functions are identified to establish uniform asymptotic stability of the closed-loop planar system. Uniform finite time stability is then proved by extending the homogeneity principle of discontinuous systems to the continuous case with uniformly decaying piecewise continuous nonhomogeneous disturbances. A finite upper bound on the settling time is also computed. The results extend the existing literature on homogeneity and finite time stability by both presenting uniform finite time stabilization and dealing with a broader class of nonhomogeneous disturbances for planar controllable systems while also proposing a new class of homogeneous continuous controllers

2009 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

This document details the results of revegetation and mitigation monitoring conducted in 2009, including 25 revegetation/restoration projects, one revegetation/mitigation project, and three bat mitigation projects

Infections by Renibacterium salmoninarum and Nanophyetus salmincola Chapin are associated with reduced growth of juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), in the Northeast Pacific Ocean

We examined 1454 juvenile Chinook salmon, Oncorhynchus tshawytscha (Walbaum), captured in nearshore waters off the coasts of Washington and Oregon (USA) from 1999 to 2004 for infection by Renibacterium salmoninarum, Nanophyetus salmincola Chapin and skin metacercariae. The prevalence and intensities for each of these infections were established for both yearling and subyearling Chinook salmon. Two metrics of salmon growth, weight residuals and plasma levels of insulin- like growth factor- 1, were determined for salmon infected with these pathogens/parasites, both individually and in combination, with uninfected fish used for comparison. Yearling Chinook salmon infected with R. salmoninarum had significantly reduced weight residuals. Chinook salmon infected with skin metacercariae alone did not have significantly reduced growth metrics. Dual infections were not associated with significantly more severe effects on the growth metrics than single infections; the number of triple infections was very low and precluded statistical comparison. Overall, these data suggest that infections by these organisms can be associated with reduced juvenile Chinook salmon growth. Because growth in the first year at sea has been linked to survival for some stocks of Chinook salmon, the infections may therefore play a role in regulating these populations in the Northeast Pacific Ocean.Keywords: pathogen, survival, parasite, disease ecologyKeywords: pathogen, survival, parasite, disease ecolog

Singularly Perturbed Monotone Systems and an Application to Double Phosphorylation Cycles

The theory of monotone dynamical systems has been found very useful in the modeling of some gene, protein, and signaling networks. In monotone systems, every net feedback loop is positive. On the other hand, negative feedback loops are important features of many systems, since they are required for adaptation and precision. This paper shows that, provided that these negative loops act at a comparatively fast time scale, the main dynamical property of (strongly) monotone systems, convergence to steady states, is still valid. An application is worked out to a double-phosphorylation ``futile cycle'' motif which plays a central role in eukaryotic cell signaling.Comment: 21 pages, 3 figures, corrected typos, references remove

Estimation of the release and migration of lead through soils and groundwater at the Hanford Site 218-E-12B Burial Ground. Volume 2, Appendices

This report describes the technical basis for a groundwater transport analysis that was conducted to evaluate migration of potentially hazardous materials from the Hanford Site 218-E-12B burial ground. The analysis characterized the geologic, chemical, and hydrologic properties of the disposal site, and used that information to perform a screening analysis for transport of materials from the burial ground to downgradient groundwater locations and to the Columbia River. Subsequent sections of the appendix describe the geologic setting, geochemistry, and hydrology of the disposal site and their relationship to the transport analysis

Growth and condition of juvenile coho salmon Oncorhynchus kisutch relate positively to species richness of trophically transmitted parasites

The aims of this study were first, to test the hypothesis that metrics of fish growth and condition relate positively to parasite species richness (S[subscript R]) in a salmonid host; second, to identify whether S[subscript R] differs as a function of host origin; third, to identify whether acquisition of parasites through marine v. freshwater trophic interactions was related to growth and condition of juvenile salmonids. To evaluate these questions, species diversity of trophically transmitted parasites in juvenile coho salmon Oncorhynchus kisutch collected off the coast of the Oregon and Washington states, U.S.A. in June 2002 and 2004 were analysed. Fish infected with three or more parasite species scored highest in metrics of growth and condition. Fish originating from the Columbia River basin had lower SR than those from the Oregon coast, Washington coast and Puget Sound, WA. Parasites obtained through freshwater or marine trophic interactions were equally important in the relationship between SR and ocean growth and condition of juvenile O. kisutch salmon.This is the publisher’s final pdf. The article is copyrighted by the Fisheries Society of the British Isles and published by John Wiley & Sons Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291095-8649

Amblyomma imitator Ticks as Vectors of Rickettsia rickettsii, Mexico

Real-time PCR of Amblyomma imitator tick egg masses obtained in Nuevo Leon State, Mexico, identified a Rickettsia species. Sequence analyses of 17-kD common antigen and outer membrane protein A and B gene fragments showed to it to be R. rickettsii, which suggested a potential new vector for this bacterium

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007

This document is the first annual report for the study titled “Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River.” Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council’s Columbia Basin Fish and Wildlife Program