68 research outputs found

    Cross-reactions of immunoglobulin M and G antibodies with enterovirus-specific viral structural proteins

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    We analysed the reactivity of enterovirus-specific human IgM and IgG antibodies with the structural proteins of different enteroviruses by the immunoblot technique. In general, all immunoglobulin G antibodies of the tested sera reacted with capsid polypeptide VP 1 of the viruses tested (echoviruses 9 and 11, coxsackievirus B3 and poliovirus 2). In contrast, enterovirus specific immunoglobulin M antibodies of adults reacted with capsid polypeptides VP 1, VP 2, and/or VP 3 of the viruses mentioned above. The reactions with VP 2 and/or VP 3 were often stronger than with VP 1. IgM antibodies from sera of newborns infected by echovirus 11 reacted with VP 1 and VP 2/3 of echovirus 11 and also with VP 2 and VP 3 of poliovirus 2. Preabsorption experiments indicate that cross-reactive IgG antibodies react with epitopes of VP 1 not present on the surface of intact virus particles. The results from the immunoblot technique were compared to data from microneutralization tests and M-antibody capture radioimmunoassay

    Two-dimensional model studies of the effect of supersonic aircraft operations on the stratospheric ozone content

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    For a fleet of 250 aircraft, the change in the ozone column is predicted to be very close to zero; in fact, the ozone overburden may actually increase as a result of show that above 25 to 30 km the ozone abundance decreases via catalytic destruction, but at lower heights it increases, mainly as a result of coupling with odd hydrogen species. Water vapor released in the engine exhaust is predicted to cause ozone decreases; for the hypothetical engines used in the study, the total column ozone changes due to water vapor emission largely offset the predicted ozone increases due to NOx emission. The actual effect of water vapor may be less than calculated because present models do not include thermal feedback. Feedback refers to the cooling effect of additional water vapor that would tend to slow the NOx reactions which destroy ozone

    SOLIDIFICATION OF THE HANFORD LAW WASTE STREAM PRODUCED AS A RESULT OF NEAR-TANK CONTINUOUS SLUDGE LEACHING AND SODIUM HYDROXIDE RECOVERY

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    The U.S. Department of Energy (DOE), Office of River Protection (ORP), is responsible for the remediation and stabilization of the Hanford Site tank farms, including 53 million gallons of highly radioactive mixed wasted waste contained in 177 underground tanks. The plan calls for all waste retrieved from the tanks to be transferred to the Waste Treatment Plant (WTP). The WTP will consist of three primary facilities including pretreatment facilities for Low Activity Waste (LAW) to remove aluminum, chromium and other solids and radioisotopes that are undesirable in the High Level Waste (HLW) stream. Removal of aluminum from HLW sludge can be accomplished through continuous sludge leaching of the aluminum from the HLW sludge as sodium aluminate; however, this process will introduce a significant amount of sodium hydroxide into the waste stream and consequently will increase the volume of waste to be dispositioned. A sodium recovery process is needed to remove the sodium hydroxide and recycle it back to the aluminum dissolution process. The resulting LAW waste stream has a high concentration of aluminum and sodium and will require alternative immobilization methods. Five waste forms were evaluated for immobilization of LAW at Hanford after the sodium recovery process. The waste forms considered for these two waste streams include low temperature processes (Saltstone/Cast stone and geopolymers), intermediate temperature processes (steam reforming and phosphate glasses) and high temperature processes (vitrification). These immobilization methods and the waste forms produced were evaluated for (1) compliance with the Performance Assessment (PA) requirements for disposal at the IDF, (2) waste form volume (waste loading), and (3) compatibility with the tank farms and systems. The iron phosphate glasses tested using the product consistency test had normalized release rates lower than the waste form requirements although the CCC glasses had higher release rates than the quenched glasses. However, the waste form failed to meet the vapor hydration test criteria listed in the WTP contract. In addition, the waste loading in the phosphate glasses were not as high as other candidate waste forms. Vitrification of HLW waste as borosilicate glass is a proven process; however the HLW and LAW streams at Hanford can vary significantly from waste currently being immobilized. The ccc glasses show lower release rates for B and Na than the quenched glasses and all glasses meet the acceptance criterion of < 4 g/L. Glass samples spiked with Re{sub 2}O{sub 7} also passed the PCT test. However, further vapor hydration testing must be performed since all the samples cracked and the test could not be performed. The waste loading of the iron phosphate and borosilicate glasses are approximately 20 and 25% respectively. The steam reforming process produced the predicted waste form for both the high and low aluminate waste streams. The predicted waste loadings for the monolithic samples is approximately 39%, which is higher than the glass waste forms; however, at the time of this report, no monolithic samples were made and therefore compliance with the PA cannot be determined. The waste loading in the geopolymer is approximately 40% but can vary with the sodium hydroxide content in the waste stream. Initial geopolymer mixes revealed compressive strengths that are greater than 500 psi for the low aluminate mixes and less than 500 psi for the high aluminate mixes. Further work testing needs to be performed to formulate a geopolymer waste form made using a high aluminate salt solution. A cementitious waste form has the advantage that the process is performed at ambient conditions and is a proven process currently in use for LAW disposal. The Saltstone/Cast Stone formulated using low and high aluminate salt solutions retained at least 97% of the Re that was added to the mix as a dopant. While this data is promising, additional leaching testing must be performed to show compliance with the PA. Compressive strength tests must also be performed on the Cast Stone monoliths to verify PA compliance. Based on testing performed for this report, the borosilicate glass and Cast Stone are the recommended waste forms for further testing. Both are proven technologies for radioactive waste disposal and the initial testing using simulated Hanford LAW waste shows compliance with the PA. Both are resistant to leaching and have greater than 25% waste loading

    An ecological framework for microbial metabolites in the ocean ecosystem

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    The ocean microbe-metabolite network involves thousands of individual metabolites that encompass a breadth of chemical diversity and biological functions. These microbial metabolites mediate biogeochemical cycles, facilitate ecological relationships, and impact ecosystem health. While analytical advancements have begun to illuminate such roles, a challenge in navigating the deluge of marine metabolomics information is to identify a subset of metabolites that have the greatest ecosystem impact. Here, we present an ecological framework to distill knowledge of fundamental metabolites that underpin marine ecosystems. We borrow terms from macroecology that describe important species, namely "dominant," "keystone," and "indicator" species, and apply these designations to metabolites within the ocean microbial metabolome. These selected metabolites may shape marine community structure, function, and health and provide focal points for enhanced study of microbe-metabolite networks. Applying ecological concepts to marine metabolites provides a path to leverage metabolomics data to better describe and predict marine microbial ecosystems

    Selective disappearance of two secreted host proteins in the course of Semliki Forest virus infection of Aedes albopictus cells

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    One secreted host protein of molecular weight 54,000 (SP 54) disappeared (from 24 to 48 h after infection) in Semliki Forest virus-infected Aedes albopictus cell clone C6/36 grown in both Mitsuhashi-Maramorosch basal medium and tissue culture medium 199 and reappeared when cells went into the permanently infected state. C6/36 is a high virus producer showing a cytopathic effect. A second secreted host protein of molecular weight 62,000 (SP 62) was prominent if cell clone C6/36 was grown in tissue culture medium 199. After infection in this medium, the protein showed a behavior similar to that described for SP 54. These secreted proteins were not affected in two original Aedes albopictus cell lines. SP 54 and SP 62 are monomeric proteins and structurally not related.</jats:p

    Cross-reactions of immunoglobulin M and G antibodies with enterovirus-specific viral structural proteins

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    SUMMARYWe analysed the reactivity of enterovirus-specific human IgM and IgG antibodies with the structural proteins of different enteroviruses by the immunoblot technique. In general, all immunoglobulin G antibodies of the tested sera reacted with capsid polypeptide VP 1 of the viruses tested (echoviruses 9 and 11, coxsackievirus B3 and poliovirus 2). In contrast, enterovirus specific immunoglobulin M antibodies of adults reacted with capsid polypeptides VP 1, VP 2, and/or VP 3 of the viruses mentioned above. The reactions with VP 2 and/or VP 3 were often stronger than with VP 1. IgM antibodies from sera of newborns infected by echovirus 11 reacted with VP 1 and VP 2/3 of echovirus 11 and also with VP 2 and VP 3 of poliovirus 2. Preabsorption experiments indicate that cross-reactive IgG antibodies react with epitopes of VP 1 not present on the surface of intact virus particles. The results from the immunoblot technique were compared to data from microneutralization tests and M-antibody capture radioimmunoassays.</jats:p

    Reaction pattern of immunoglobulin M and G antibodies to echovirus 11 structural proteins

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    The immunoglobulin M and G specific immune response of humans to echovirus 11 proteins during an echovirus 11 outbreak was studied by the immunoblot technique. Whereas immunoglobulin G antibodies were directed most exclusively to the VP 1 protein, the immunoglobulin M antibodies were directed against VP 1, VP 2, and VP 3.</jats:p

    Cross-reactions of immunoglobulin M and G antibodies with enterovirus-specific viral structural proteins.

    Get PDF
    We analysed the reactivity of enterovirus-specific human IgM and IgG antibodies with the structural proteins of different enteroviruses by the immunoblot technique. In general, all immunoglobulin G antibodies of the tested sera reacted with capsid polypeptide VP 1 of the viruses tested (echoviruses 9 and 11, coxsackievirus B3 and poliovirus 2). In contrast, enterovirus specific immunoglobulin M antibodies of adults reacted with capsid polypeptides VP 1, VP 2, and/or VP 3 of the viruses mentioned above. The reactions with VP 2 and/or VP 3 were often stronger than with VP 1. IgM antibodies from sera of newborns infected by echovirus 11 reacted with VP 1 and VP 2/3 of echovirus 11 and also with VP 2 and VP 3 of poliovirus 2. Preabsorption experiments indicate that cross-reactive IgG antibodies react with epitopes of VP 1 not present on the surface of intact virus particles. The results from the immunoblot technique were compared to data from microneutralization tests and M-antibody capture radioimmunoassays

    Detection of reverse transcriptase activity in live attenuated virus vaccines.

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    BACKGROUND: Safety considerations require that biological products for human use are free from any agent that might pose a potential health hazard. One method to detect the presence of retroviral particles is the reverse transcriptase (RT) assay. This assay is capable of detecting all infectious retrovirus particles, irrespective of genome or protein composition. Recently, a family of ultrasensitive RT tests, named product-enhanced reverse transcriptase (PERT) assays, has been designed with a detection limit that is 10(6) - 10(7) times lower than that of conventional RT tests. OBJECTIVES: To investigate with the PERT assay whether RT activity is detectable in live attenuated virus vaccines and to characterize eventual RT activities. STUDY DESIGN: A total of 12 different monovalent and one trivalent virus vaccines containing live attenuated viruses were tested for RT activity with the PERT assay and a conventional RT test. RT activities were investigated with respect to their susceptibility to RT inhibitors, association with physical particles, and their possible origin. RESULTS: One trivalent and five different monovalent vaccines contained RT activity when tested with the PERT assay, but were negative in a conventional RT assay. All lots tested of these vaccines showed RT activity. The activity in all vaccines was sensitive to AZT-triphosphate and ddTTP and at least part of it was associated with particles. Mg(2+)-dependent RT activity banded at a density of 1.14 g/ml. All positive vaccines were produced using chicken cells. CONCLUSIONS: The data indicate the systematic presence of partially particle-associated retroviral reverse transcriptase in attenuated live virus vaccines that are produced in chicken-derived cells. The identification and further characterization of these particles, as well as the elucidation of possible interactions with the human organism are imperative goals despite the fact that these vaccines have been safely used for many years
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