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  1. Article ; Online: ADAMTS13 autoantibodies cloned from patients with acquired thrombotic thrombocytopenic purpura: 1. Structural and functional characterization in vitro.

    Ostertag, Eric M / Kacir, Stephen / Thiboutot, Michelle / Gulendran, Gayathri / Zheng, X Long / Cines, Douglas B / Siegel, Don L

    Transfusion

    2016  Volume 56, Issue 7, Page(s) 1763–1774

    Abstract: Background: Acquired thrombotic thrombocytopenia purpura (TTP) is a life-threatening illness caused by autoantibodies that decrease the activity of ADAMTS13, the von Willebrand factor-cleaving protease. Despite efficacy of plasma exchange, mortality ... ...

    Abstract Background: Acquired thrombotic thrombocytopenia purpura (TTP) is a life-threatening illness caused by autoantibodies that decrease the activity of ADAMTS13, the von Willebrand factor-cleaving protease. Despite efficacy of plasma exchange, mortality remains high and relapse is common. Improved therapies may come from understanding the diversity of pathogenic autoantibodies on a molecular or genetic level. Cloning comprehensive repertoires of patient autoantibodies can provide the necessary tools for studying immunobiology of disease and developing animal models.
    Study design and methods: Anti-ADAMTS13 antibodies were cloned from four patients with acquired TTP using phage display and characterized with respect to genetic origin, inhibition of ADAMTS13 proteolytic activity, and epitope specificity. Anti-idiotypic antisera raised to a subset of autoantibodies enabled comparison of their relatedness to each other and to polyclonal immunoglobulin (Ig)G in patient plasma.
    Results: Fifty-one unique antibodies were isolated comprising epitope specificities resembling the diversity found in circulating patient IgG. Antibodies directed both to the amino terminal domains and to those requiring the ADAMTS13 cysteine-rich/spacer region for binding inhibited proteolytic activity, while those solely targeting carboxy-terminal domains were noninhibitory. Anti-idiotypic antisera raised to a subset of antibody clones crossreacted with and reduced the inhibitory activity of polyclonal IgG from a set of unrelated patients.
    Conclusions: Anti-ADAMTS13 autoantibodies isolated by repertoire cloning display the diversity of epitope specificities found in patient plasma and provide tools for developing animal models of acquired TTP. Shared idiotypes of inhibitory clones with circulating IgG from multiple patients suggest common features of pathogenic autoantibodies that could be exploited for developing more targeted therapies.
    MeSH term(s) ADAMTS13 Protein/immunology ; Adult ; Antibody Specificity ; Autoantibodies/isolation & purification ; Cell Surface Display Techniques ; Child ; Cloning, Molecular ; Cross Reactions/immunology ; Epitope Mapping ; Humans ; Immunoglobulin G/blood ; Middle Aged ; Purpura, Thrombotic Thrombocytopenic/immunology
    Chemical Substances Autoantibodies ; Immunoglobulin G ; ADAMTS13 Protein (EC 3.4.24.87) ; ADAMTS13 protein, human (EC 3.4.24.87)
    Language English
    Publishing date 2016-04-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 208417-x
    ISSN 1537-2995 ; 0041-1132
    ISSN (online) 1537-2995
    ISSN 0041-1132
    DOI 10.1111/trf.13584
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: ADAMTS13 autoantibodies cloned from patients with acquired thrombotic thrombocytopenic purpura: 2. Pathogenicity in an animal model.

    Ostertag, Eric M / Bdeir, Khalil / Kacir, Stephen / Thiboutot, Michelle / Gulendran, Gayathri / Yunk, Lenka / Hayes, Vincent M / Motto, David G / Poncz, Mortimer / Zheng, X Long / Cines, Douglas B / Siegel, Don L

    Transfusion

    2016  Volume 56, Issue 7, Page(s) 1775–1785

    Abstract: Background: Acquired thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease in which ultralarge von Willebrand factor (UL-VWF) multimers accumulate as a result of autoantibody inhibition of the VWF protease, ADAMTS13. Current treatment ...

    Abstract Background: Acquired thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease in which ultralarge von Willebrand factor (UL-VWF) multimers accumulate as a result of autoantibody inhibition of the VWF protease, ADAMTS13. Current treatment is not specifically directed at the responsible autoantibodies and in some cases is ineffective or of transient benefit. More rational, reliable, and durable therapies are needed, and a human autoantibody-mediated animal model would be useful for their development. Previously, TTP patient anti-ADAMTS13 single-chain variable-region fragments (scFv's) were cloned that inhibited ADAMTS13 proteolytic activity in vitro and expressed features in common with inhibitory immunoglobulin G in patient plasma. Here, pathogenicity of these scFv's is explored in vivo by transfecting mice with inhibitory antibody cDNA.
    Study design and methods: Hydrodynamic tail vein injection of naked DNA encoding human anti-ADAMTS13 scFv was used to create sustained ADAMTS13 inhibition in mice. Accumulation of UL-VWF multimers was measured and formation of platelet (PLT) thrombi after focal or systemic vascular injury was examined.
    Results: Transfected mice expressed physiological plasma levels of human scFv and developed sustained ADAMTS13 inhibition and accumulation of unprocessed UL-VWF multimers. Induced focal endothelial injury generated PLT thrombi extending well beyond the site of initial injury, and systemic endothelial injury induced thrombocytopenia, schistocyte formation, PLT thrombi, and death.
    Conclusions: These results demonstrate for the first time the ability of human recombinant monovalent anti-ADAMTS13 antibody fragments to recapitulate key pathologic features of untreated acquired TTP in vivo, validating their clinical significance and providing an animal model for testing novel targeted therapeutic approaches.
    MeSH term(s) ADAMTS13 Protein/antagonists & inhibitors ; ADAMTS13 Protein/immunology ; Animals ; Autoantibodies/genetics ; Cloning, Molecular ; DNA, Complementary/administration & dosage ; Humans ; Mice ; Models, Animal ; Molecular Targeted Therapy/methods ; Purpura, Thrombotic Thrombocytopenic/immunology ; Purpura, Thrombotic Thrombocytopenic/therapy ; Single-Chain Antibodies/genetics ; Single-Chain Antibodies/toxicity ; von Willebrand Factor/metabolism
    Chemical Substances Autoantibodies ; DNA, Complementary ; Single-Chain Antibodies ; von Willebrand Factor ; ADAMTS13 Protein (EC 3.4.24.87) ; ADAMTS13 protein, human (EC 3.4.24.87)
    Language English
    Publishing date 2016-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 208417-x
    ISSN 1537-2995 ; 0041-1132
    ISSN (online) 1537-2995
    ISSN 0041-1132
    DOI 10.1111/trf.13583
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Chikungunya: a potentially emerging epidemic?

    Thiboutot, Michelle M / Kannan, Senthil / Kawalekar, Omkar U / Shedlock, Devon J / Khan, Amir S / Sarangan, Gopalsamy / Srikanth, Padma / Weiner, David B / Muthumani, Karuppiah

    PLoS neglected tropical diseases

    2010  Volume 4, Issue 4, Page(s) e623

    Abstract: Chikungunya virus is a mosquito-borne emerging pathogen that has a major health impact in humans and causes fever disease, headache, rash, nausea, vomiting, myalgia, and arthralgia. Indigenous to tropical Africa, recent large outbreaks have been reported ...

    Abstract Chikungunya virus is a mosquito-borne emerging pathogen that has a major health impact in humans and causes fever disease, headache, rash, nausea, vomiting, myalgia, and arthralgia. Indigenous to tropical Africa, recent large outbreaks have been reported in parts of South East Asia and several of its neighboring islands in 2005-07 and in Europe in 2007. Furthermore, positive cases have been confirmed in the United States in travelers returning from known outbreak areas. Currently, there is no vaccine or antiviral treatment. With the threat of an emerging global pandemic, the peculiar problems associated with the more immediate and seasonal epidemics warrant the development of an effective vaccine. In this review, we summarize the evidence supporting these concepts.
    MeSH term(s) Africa/epidemiology ; Alphavirus Infections/epidemiology ; Alphavirus Infections/prevention & control ; Alphavirus Infections/virology ; Asia, Southeastern/epidemiology ; Chikungunya virus/immunology ; Chikungunya virus/isolation & purification ; Communicable Diseases, Emerging/epidemiology ; Communicable Diseases, Emerging/prevention & control ; Communicable Diseases, Emerging/virology ; Europe/epidemiology ; Humans ; Travel ; United States/epidemiology ; Viral Vaccines/immunology
    Chemical Substances Viral Vaccines
    Keywords covid19
    Language English
    Publishing date 2010-04-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2429704-5
    ISSN 1935-2735 ; 1935-2727
    ISSN (online) 1935-2735
    ISSN 1935-2727
    DOI 10.1371/journal.pntd.0000623
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Chikungunya

    Michelle M Thiboutot / Senthil Kannan / Omkar U Kawalekar / Devon J Shedlock / Amir S Khan / Gopalsamy Sarangan / Padma Srikanth / David B Weiner / Karuppiah Muthumani

    PLoS Neglected Tropical Diseases, Vol 4, Iss 4, p e

    a potentially emerging epidemic?

    2010  Volume 623

    Abstract: Chikungunya virus is a mosquito-borne emerging pathogen that has a major health impact in humans and causes fever disease, headache, rash, nausea, vomiting, myalgia, and arthralgia. Indigenous to tropical Africa, recent large outbreaks have been reported ...

    Abstract Chikungunya virus is a mosquito-borne emerging pathogen that has a major health impact in humans and causes fever disease, headache, rash, nausea, vomiting, myalgia, and arthralgia. Indigenous to tropical Africa, recent large outbreaks have been reported in parts of South East Asia and several of its neighboring islands in 2005-07 and in Europe in 2007. Furthermore, positive cases have been confirmed in the United States in travelers returning from known outbreak areas. Currently, there is no vaccine or antiviral treatment. With the threat of an emerging global pandemic, the peculiar problems associated with the more immediate and seasonal epidemics warrant the development of an effective vaccine. In this review, we summarize the evidence supporting these concepts.
    Keywords Arctic medicine. Tropical medicine ; RC955-962 ; Public aspects of medicine ; RA1-1270
    Language English
    Publishing date 2010-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article: Behavior of energetic materials in ground water at an anti-tank range.

    Martel, Richard / Mailloux, Michel / Gabriel, Uta / Lefebvre, René / Thiboutot, Sonia / Ampleman, Guy

    Journal of environmental quality

    2009  Volume 38, Issue 1, Page(s) 75–92

    Abstract: An environmental issue has arisen with M-72 malfunction on anti-tank ranges ... mass balance on a transect perpendicular to ground water flow, about 300 m downgradient of the impact area ...

    Abstract An environmental issue has arisen with M-72 malfunction on anti-tank ranges because many of these rockets break into pieces without exploding on impact, dispersing their energetic materials content on the ground surface and exposing them to transport by infiltration of rainfall and snowmelt. A case study (1998--2005) at Arnhem Anti-Tank Range (Garrison Valcartier, Canada, in operation since the 1970s) revealed octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) contamination and traces of 1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) in ground water at varying concentrations, with all detected HMX concentrations below the USEPA guideline for drinking water of 400 microg L(-1). An HMX mass balance on a transect perpendicular to ground water flow, about 300 m downgradient of the impact area, indicated an HMX flux of about 3 g d(-1) (0.7-1 kg yr(-1), 2005). The HMX mass in the impact area on the sand terrace was estimated at 7 to 10 kg (in 2005). The annual dissolved HMX flux represents about 10% of the source. The dissolved HMX plume in ground water consisted of a series of slugs, generated at each significant infiltration event. HMX is weakly retarded by sorption and is neither biotransformed nor mineralized under the aerobic conditions of the aquifer. TNT and RDX exceeded the USEPA guideline (2 microg L(-1) RDX and 1 microg L(-1) TNT) in three and two samples, respectively. The TNT plume was discontinuous because this compound was not always present at the ground surface. TNT is biotransformed, weakly sorbed, and not mineralized. In two wells, perchlorate associated with the propellant was found at concentrations above the Health Canada preliminary guideline of 6 microg L(-1) near the firing position.
    MeSH term(s) Adsorption ; Azocines/analysis ; Biodegradation, Environmental ; Canada ; Industrial Waste/analysis ; Metals/analysis ; Military Science ; Nitrogen Compounds/analysis ; Perchlorates/analysis ; Photolysis ; Soil Pollutants/analysis ; Triazines/analysis ; Trinitrotoluene/analysis ; Water/analysis ; Water/chemistry ; Water Pollutants, Chemical/analysis ; Weapons
    Chemical Substances Azocines ; Industrial Waste ; Metals ; Nitrogen Compounds ; Perchlorates ; Soil Pollutants ; Triazines ; Water Pollutants, Chemical ; Water (059QF0KO0R) ; Trinitrotoluene (118-96-7) ; octogen (LLW94W5BSJ) ; perchlorate (VLA4NZX2P4) ; cyclonite (W91SSV5831)
    Language English
    Publishing date 2009-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.2134/jeq2007.0606
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: Hydrogeological study of an anti-tank range.

    Mailloux, Michel / Martel, Richard / Gabriel, Uta / Lefebvre, René / Thiboutot, Sonia / Ampleman, Guy

    Journal of environmental quality

    2008  Volume 37, Issue 4, Page(s) 1468–1476

    Abstract: ... variable flow velocities (from < 3 to 1200 m/yr) and transient flow regime in the regional aquifer below ...

    Abstract The Arnhem Anti-Tank Range (Canadian Forces Base [CFB] Valcartier, Canada, in operation since the 1970s) has been characterized, including the drilling, installation, and characterization of 25 wells and a ground-penetrating radar survey. The observed particular features of this site include highly variable flow velocities (from < 3 to 1200 m/yr) and transient flow regime in the regional aquifer below the contaminant source zone of the impact area, sharp flow direction shifts, discontinuous stratigraphy and a local perched aquifer. A transient ground water flow model permitted us to understand how the complex hydrogeological setting shapes contaminant transport in the regional aquifer. The model explains the highly variable energetic material (EM) concentrations measured in the plume with peaks associated to spring and to a lesser extent to fall recharge events. As a conclusion from this work, the authors suggest that the characterization of contaminant sources on slopes should extend over all seasons to be sure to detect potential transient flow conditions and variable contaminant concentrations.
    MeSH term(s) Environmental Monitoring/methods ; Geological Phenomena ; Geology ; Radar ; Water
    Chemical Substances Water (059QF0KO0R)
    Language English
    Publishing date 2008-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.2134/jeq2007.0605
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Behavior of Energetic Materials in Ground Water at an Anti-Tank Range

    Martel, Richard / Ampleman, Guy / Gabriel, Uta / Lefebvre, René / Mailloux, Michel / Thiboutot, Sonia

    Journal of environmental quality. 2009 Jan., v. 38, no. 1

    2009  

    Abstract: An environmental issue has arisen with M-72 malfunction on anti-tank ranges ... on a transect perpendicular to ground water flow, about 300 m downgradient of the impact area, indicated an HMX ...

    Abstract An environmental issue has arisen with M-72 malfunction on anti-tank ranges because many of these rockets break into pieces without exploding on impact, dispersing their energetic materials content on the ground surface and exposing them to transport by infiltration of rainfall and snowmelt. A case study (1998–2005) at Arnhem Anti-Tank Range (Garrison Valcartier, Canada, in operation since the 1970s) revealed octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) contamination and traces of 1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) in ground water at varying concentrations, with all detected HMX concentrations below the USEPA guideline for drinking water of 400 μg L−1 An HMX mass balance on a transect perpendicular to ground water flow, about 300 m downgradient of the impact area, indicated an HMX flux of about 3 g d−1 (0.7–1 kg yr−1, 2005). The HMX mass in the impact area on the sand terrace was estimated at 7 to 10 kg (in 2005). The annual dissolved HMX flux represents about 10% of the source. The dissolved HMX plume in ground water consisted of a series of slugs, generated at each significant infiltration event. HMX is weakly retarded by sorption and is neither biotransformed nor mineralized under the aerobic conditions of the aquifer. TNT and RDX exceeded the USEPA guideline (2 μg L−1 RDX and 1 μg L−1 TNT) in three and two samples, respectively. The TNT plume was discontinuous because this compound was not always present at the ground surface. TNT is biotransformed, weakly sorbed, and not mineralized. In two wells, perchlorate associated with the propellant was found at concentrations above the Health Canada preliminary guideline of 6 μg L−1 near the firing position.
    MeSH term(s) Adsorption ; Azocines/analysis ; Biodegradation, Environmental ; Industrial Waste/analysis ; Metals/analysis ; Military Science ; Nitrogen Compounds/analysis ; Perchlorates/analysis ; Photolysis ; Soil Pollutants/analysis ; Triazines/analysis ; Trinitrotoluene/analysis ; Water Pollutants, Chemical/analysis ; Water/analysis/chemistry ; Weapons
    Keywords aquifers ; case studies ; drinking water ; explosives ; groundwater contamination ; hydrogeology ; infiltration (hydrology) ; military lands ; perchlorates ; trinitrotoluene ; wells ; Canada
    Language English
    Dates of publication 2009-01
    Size p. 75-92.
    Publishing place American Society of Agronomy, Crop Science Society of America, Soil Science Society
    Document type Article
    Note epub
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.2134/jeq2007.0606
    Database NAL-Catalogue (AGRICOLA)

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  8. Article: Hydrogeological Study of an Anti-Tank Range

    Mailloux, Michel / Ampleman, Guy / Gabriel, Uta / Lefebvre, René / Martel, Richard / Thiboutot, Sonia

    Journal of environmental quality. 2008 July, v. 37, no. 4

    2008  

    Abstract: ... variable flow velocities (from < 3 to 1200 m/yr) and transient flow regime in the regional aquifer below ...

    Abstract The Arnhem Anti-Tank Range (Canadian Forces Base [CFB] Valcartier, Canada, in operation since the 1970s) has been characterized, including the drilling, installation, and characterization of 25 wells and a ground-penetrating radar survey. The observed particular features of this site include highly variable flow velocities (from < 3 to 1200 m/yr) and transient flow regime in the regional aquifer below the contaminant source zone of the impact area, sharp flow direction shifts, discontinuous stratigraphy and a local perched aquifer. A transient ground water flow model permitted us to understand how the complex hydrogeological setting shapes contaminant transport in the regional aquifer. The model explains the highly variable energetic material (EM) concentrations measured in the plume with peaks associated to spring and to a lesser extent to fall recharge events. As a conclusion from this work, the authors suggest that the characterization of contaminant sources on slopes should extend over all seasons to be sure to detect potential transient flow conditions and variable contaminant concentrations.
    MeSH term(s) Environmental Monitoring/methods ; Geological Phenomena ; Geology ; Radar ; Water
    Keywords aquifers ; explosives ; ground-penetrating radar ; groundwater contamination ; groundwater flow ; hydrogeology ; hydrologic models ; military lands ; perchlorates ; pollutants ; slope ; stratigraphy ; trinitrotoluene ; Quebec
    Language English
    Dates of publication 2008-07
    Size p. 1468-1476.
    Publishing place American Society of Agronomy, Crop Science Society of America, Soil Science Society
    Document type Article
    Note epub
    ZDB-ID 120525-0
    ISSN 1537-2537 ; 0047-2425
    ISSN (online) 1537-2537
    ISSN 0047-2425
    DOI 10.2134/jeq2007.0605
    Database NAL-Catalogue (AGRICOLA)

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