BACKGROUND
Transfusion of plasma from recovered patients after
Ebolavirus
(EBOV) infection, typically called “convalescent plasma,” is an effective treatment for active disease available in endemic ...areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV+RB) is effective against multiple enveloped, negative‐sense, single‐stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV+RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of Ebola virus disease (EVD).
STUDY DESIGN AND METHODS
Four in vitro experiments were conducted to evaluate effects of UV+RB on green fluorescent protein EBOV (EBOV‐GFP), wild‐type EBOV in serum, and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1 to 3 were 4.21 log GFP units/mL, 4.96 log infectious units/mL, and 4.23 log plaque‐forming units/mL. Conditions tested in the first three experiments included the following: 1—EBOV‐GFP plus UV+RB; 2—EBOV‐GFP plus RB only; 3—EBOV‐GFP plus UV only; 4—EBOV‐GFP without RB or UV; 5—virus‐free control plus UV only; and 6—virus‐free control without RB or UV.
RESULTS
UV+RB reduced EBOV titers to nondetectable levels in both nonhuman primate serum (≥2.8‐ to 3.2‐log reduction) and human whole blood (≥3.0‐log reduction) without decreasing protective antibody titers in human plasma.
CONCLUSION
Our in vitro results demonstrate that the UV+RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV+RB can improve convalescent blood product safety is indicated.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
BACKGROUND: Emergency whole blood transfusion is a lifesaving procedure employed on modern battlefields. Rapid device tests (RDTs) are frequently used to mitigate transfusion‐transmitted infection ...risks.
STUDY DESIGN AND METHODS: A limited evaluation of the RDT formerly used on battlefields was performed using 50 donor plasma samples and commercially available panels. Five hepatitis C virus (HCV) RDTs with sufficient stated sensitivity and thermostability were assessed using 335 HCV‐positive and 339 HCV‐negative donor plasma samples, 54 seroconversion panel plasma samples, and 84 HCV‐positive and 84 HCV‐negative spiked whole blood under normal, hot, and cold storage conditions and normal and hot test conditions, plus an ease‐of‐use survey.
RESULTS: BioRapid HCV test sensitivity on donor plasma was 84% (95% confidence interval CI, 70.9%‐92.8%). Using all positive plasma samples, OraQuick HCV sensitivity exceeded all comparators (99.4%, 95% CI, 98.0%‐99.9%, p < 0.05). Specificity was consistently high, led by OraQuick HCV at 99.7% (95% CI, 98.6%‐100%), statistically superior only to Axiom HCV (p < 0.05). Using seroconversion panels, only OraQuick HCV showed equivalent or earlier HCV detection compared to the gold standard. Using spiked whole blood, specificity was consistently high, and sensitivity ranged significantly from 34.5% (95% CI, 25.0%‐45.1%) for CORE HCV to 98.8% (95% CI, 94.3%‐99.9%) for OraQuick HCV. All comparator RDTs were significantly less sensitive than OraQuick HCV at one or more stress condition.
CONCLUSION: This HCV RDT comparison identified significant sensitivity differences, particularly using whole blood under extreme storage and testing conditions. These data support OraQuick HCV superiority and illustrate the value of RDT evaluation under simulated field conditions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Injection drug use (IDU), specifically non-intravenous “skin-popping” of heroin, seems to provide optimal conditions for Clostridial infection and toxin production. IDU is therefore a major risk ...factor for wound botulism and Clostridial necrotizing soft tissue infections (NSTI) and continues to be linked to cases of tetanus. Case clusters of all 3 diseases have occurred among IDUs in Western U.S. and Europe. Medical personnel who care for the IDU population must be thoroughly familiar with the clinical presentation and management of these diseases. Wound botulism presents with bulbar symptoms and signs that are easily overlooked; rapid acquisition and administration of antitoxin can prevent neuromuscular respiratory failure. In addition to Clostridium perfringens, IDU-related NSTIs can be caused by Clostridium sordellii and Clostridium novyi, which may share a distinct clinical presentation. Early definitive NSTI management, which decreases mortality, requires a low index of suspicion on the part of emergency physicians and low threshold for surgical exploration and debridement on the part of the surgeon. Tetanus should be preventable in the IDU population through careful attention to vaccination status.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
El efecto Peltier, el cual se origina por el paso de una corriente eléctrica a través de la unión de dos conductores distintos, es un fenómeno que puede ser aprovechado para procesos de refrigeración ...y aire acondicionado. Para obtener el efecto refrigerante, con un dispositivo o celda Peltier, solo es necesario realizar trabajo eléctrico. Sin embargo, su uso es limitado debido a su bajo coeficiente de desempeño (COP).Los sistemas de refrigeración termoeléctricos no están en condiciones de competir con sistemas convencionales, debido a su desempeño energético. A pesar de ello, es una opción que debe ser explotada, debido a que su principal ventaja es no utilizar gases refrigerantes. Para ello, los parámetros relacionados con el coeficiente de performance (COP) deben ser diseñados, de tal forma que el sistema opere cerca del punto de máximo desempeño.Las superficies extendidas (aletas), son componentes que permiten el intercambio de calor, forman parte esencial de un sistema de refrigeración termoeléctrica. La magnitud de las resistencias térmicas influye en el desempeño de la celda Peltier. Por lo tanto, para el presente trabajo se realiza el análisis del comportamiento del sistema, formado por una celda Peltier el cual utiliza superficies extendidas. El objetivo principal es determinar la relación entre el coeficiente de desempeño de celda Peltier seleccionada, la cual permita extraer una carga de refrigeración de 100 W con las resistencias térmicas de sus focos frío y caliente. Se considera que las superficies extendidas son de aluminio y se ha elegido una celda Peltier comercial (TEC1-24126), formado por termopares de telururo de bismuto (Bi2Te3).En el modelamiento se ha considerado los procesos de transferencia de calor en superficies extendidas; flujo interno del aire y las relaciones termodinámicas entre los flujos de calor y trabajo en la celda Peltier. Las ecuaciones planteadas se han resuelto utilizando el software: “Engenering Equation Solver (EES)”, que utiliza una variación del método de Newton, para resolver sistemas de ecuaciones no lineales.Para el prototipo propuesto se ha comprobado la magnitud de cada resistencia térmica. La resistencia total en lado frío y caliente, respectivamente son 0,0838 W/K y 0,0840 W/K. Cada resistencia térmica está conformada por la resistencia de contacto, la resistencia de constricción o propagación y la resistencia térmica de la superficie extendida, la resistencia térmica más significativa corresponde a la superficie extendida que representa el 83%, luego la de constricción o propagación que representa un 12%, finalmente la resistencia térmica de contacto con un 5%. Con dichos valores, la celda Peltier seleccionada puede extraer una carga térmica de 101,4 W, con un coeficiente de desempeño de 0,65.
We describe the equivariant cohomology ring of rationally smooth projective embeddings of reductive groups. These embeddings are the projectivizations of reductive monoids. Our main result describes ...their equivariant cohomology in terms of roots, idempotents, and underlying monoid data. Also, we characterize those embeddings whose equivariant cohomology ring is obtained via restriction to the associated toric variety. Such characterization is given in terms of the closed orbits.
We provide a notion of algebraic rational cell with applications to intersection theory on singular varieties with torus action. Based on this notion, we study the algebraic analogue of ...\(\mathbb{Q}\)-filtrable varieties: algebraic varieties where a torus acts with isolated fixed points, such that the associated Bialynicki-Birula decomposition consists of algebraic rational cells. We show that the rational equivariant Chow group of any \(\mathbb{Q}\)-filtrable variety is freely generated by the cell closures. We apply this result to group embeddings, and more generally to spherical varieties. This paper is an extension of arxiv.org/abs/1112.0365 to equivariant Chow groups.
We study \(T\)-linear schemes, a class of objects that includes spherical and Schubert varieties. We provide a localization theorem for the equivariant Chow cohomology of these schemes that does not ...depend on resolution of singularities. Furthermore, we give an explicit presentation of the equivariant Chow cohomology of possibly singular complete spherical varieties admitting a smooth equivariant envelope (e.g. group embeddings).
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