1. Resources
  2. Citations Library

Citation Details

You are viewing citation details. You can save or export citation(s) below, access an article, or start a new search.

471–480 of 499 records found matching your query:
Back to Search
Select All  |  Deselect All

Headers act as filters

      1. Author :
        Filip K. Swirski, Matthias Nahrendorf, Martin Etzrodt, Moritz Wildgruber, Virna Cortez-Retamozo, Peter Panizzi, Jose-Luiz Figueiredo, Rainer H. Kohler, Aleksey Chudnovskiy, Peter Waterman, Elena Aikawa, Thorsten R. Mempel, Peter Libby, Ralph Weissleder and Mikael J. Pittet
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Science
      6. Products :
      7. Volume :
        325
      8. Issue :
        5940
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research; Immunology
      11. Keywords :
        splenic monocytes; in vivo imaging; ProSense; FMT; fluorescence molecular tomography
      12. Abstract :
        A current paradigm states that monocytes circulate freely and patrol blood vessels but differentiate irreversibly into dendritic cells (DCs) or macrophages upon tissue entry. Here we show that bona fide undifferentiated monocytes reside in the spleen and outnumber their equivalents in circulation. The reservoir monocytes assemble in clusters in the cords of the subcapsular red pulp and are distinct from macrophages and DCs. In response to ischemic myocardial injury, splenic monocytes increase their motility, exit the spleen en masse, accumulate in injured tissue, and participate in wound healing. These observations uncover a role for the spleen as a site for storage and rapid deployment of monocytes and identify splenic monocytes as a resource that the body exploits to regulate inflammation.
      13. URL :
        http://www.sciencemag.org/content/325/5940/612.abstract
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4567
      1. Author :
        Matthias Nahrendorf, Peter Waterman, Greg Thurber, Kevin Groves, Milind Rajopadhye, Peter Panizzi, Brett Marinelli, Elena Aikawa, Mikael J Pittet, Filip K Swirski and Ralph Weissleder
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Arteriosclerosis, Thrombosis, and Vascular Biology
      6. Products :
      7. Volume :
        29
      8. Issue :
        10
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        FMT-CT; molecular imaging; atherosclerosis; protease activity; inflammation; in vivo imaging; fluorescence molecular tomography; ProSense
      12. Abstract :
        Objective: Proteases are emerging biomarkers of inflammatory diseases. In atherosclerosis, these enzymes are often secreted by inflammatory macrophages, digest the extracellular matrix of the fibrous cap and destabilize atheromata. Protease function can be monitored with protease activatable imaging probes and quantitated in vivo by fluorescence molecular tomography (FMT). To address two major constraints currently associated with imaging of murine atherosclerosis (lack of highly sensitive probes and absence of anatomical information), we compared protease sensors (PS) of variable size and pharmacokinetics and co-registered FMT datasets with computed tomography (FMT-CT).

        Methods and results: Co-registration of FMT and CT was achieved with a multimodal imaging cartridge containing fiducial markers detectable by both modalities. A high-resolution CT angiography protocol accurately localized fluorescence to the aortic root of atherosclerotic apoE-/- mice. To identify suitable sensors, we first modeled signal kinetics in-silico and then compared three probes with identical oligo-L-lysine cleavage sequences: PS-5, 5nm in diameter containing 2 fluorochromes , PS-25, a 25nm version with an elongated lysine chain and PS-40, a polymeric nanoparticle. Serial FMT-CT showed fastest kinetics for PS-5 but, surprisingly, highest fluorescence in lesions of the aortic root for PS-40. PS-40 robustly reported therapeutic effects of atorvastatin, corroborated by ex vivo imaging and qPCR for the model protease cathepsin B.

        Conclusions: FMT-CT is a robust and observer-independent tool for non-invasive assessment of inflammatory murine atherosclerosis. Reporter-containing nanomaterials may have unique advantages over small molecule agents for in vivo imaging.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2746251/?tool=pubmed
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4568
      1. Author :
        Filip K. Swirski, Ralph Weissleder and Mikael J. Pittet
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        N/A
      5. Publication :
        Arteriosclerosis, Thrombosis, and Vascular Biology
      6. Products :
      7. Volume :
        N/A
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        atherosclerosis; in vivo imaging; monocytes; VivoTag; FMT; fluorescence molecular tomography
      12. Abstract :
        Monocytes and macrophages play active roles in atherosclerosis, a chronic inflammatory disease that is a leading cause of death in the developed world. The prevailing paradigm states that, during human atherogenesis, monocytes accumulate in the arterial intima and differentiate into macrophages, which then ingest oxidized lipoproteins, secrete a diverse array of proinflammatory mediators, and eventually become foam cells, the key constituents of a vulnerable plaque. Yet monocytes are heterogeneous. In the mouse, one subset (Ly-6Chi) promotes inflammation, expands in hypercholesterolemic conditions, and selectively gives rise to macrophages in atheromata. A different subset (Ly-6Clo) attenuates inflammation and promotes angiogenesis and granulation tissue formation in models of tissue injury, but its role in atherosclerosis is largely unknown. In the human, monocyte heterogeneity is preserved but it is still unresolved how subsets correspond functionally. The contradistinctive properties of these cells suggest commitment for specific function before infiltrating tissue. Such commitment argues for discriminate targeting of deleterious subsets while sparing host defense and repair mechanisms. In addition to advancing our understanding of atherosclerosis, the ability to target and image monocyte subsets would allow us to evaluate drugs designed to selectively inhibit monocyte subset recruitment or function, and to stratify patients at risk for developing complications such as myocardial infarction or stroke. In this review we summarize recent advances of our understanding of the behavioral heterogeneity of monocytes during disease progression and outline emerging molecular imaging approaches to address key questions in the field.
      13. URL :
        http://atvb.ahajournals.org/cgi/content/abstract/ATVBAHA.108.180521v1
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4569
      1. Author :
        Thomas Christen, Matthias Nahrendorf, Moritz Wildgruber, Filip K. Swirski, Elena Aikawa, Peter Waterman, Koichi Shimizu, Ralph Weissleder and Peter Libby
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Circulation
      6. Products :
      7. Volume :
        119
      8. Issue :
        14
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        In vivo imaging; inflammation; leukocytes; rejection; transplantation; fluorescence molecular tomography; FMT; Prosense
      12. Abstract :
        Background: Clinical detection of transplant rejection by repeated endomyocardial biopsy requires catheterization and entails risks. Recently developed molecular and cellular imaging techniques that visualize macrophage host responses could provide a noninvasive alternative. Yet, which macrophage functions may provide useful markers for detecting parenchymal rejection remains uncertain.

        Methods and Results: We transplanted isografts from B6 mice and allografts from Balb/c mice heterotopically into B6 recipients. In this allograft across major histocompatability barriers, the transplanted heart undergoes predictable progressive rejection, leading to graft failure after 1 week. During rejection, crucial macrophage functions, including phagocytosis and release of proteases, render these abundant innate immune cells attractive imaging targets. Two or 6 days after transplantation, we injected either a fluorescent protease sensor or a magnetofluorescent phagocytosis marker. Histological and flow cytometric analyses established that macrophages function as the major cellular signal source. In vivo, we obtained a 3-dimensional functional map of macrophages showing higher phagocytic uptake of magnetofluorescent nanoparticles during rejection using magnetic resonance imaging and higher protease activity in allografts than in isografts using tomographic fluorescence. We further assessed the sensitivity of imaging to detect the degree of rejection. In vivo imaging of macrophage response correlated closely with gradually increasing allograft rejection and attenuated rejection in recipients with a genetically impaired immune response resulting from a deficiency in recombinase-1 (RAG-1-/-).

        Conclusions: Molecular imaging reporters of either phagocytosis or protease activity can detect cardiac allograft rejection noninvasively, promise to enhance the search for novel tolerance-inducing strategies, and have translational potential.
      13. URL :
        http://circ.ahajournals.org/cgi/content/abstract/circulationaha;119/14/1925
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4640
      1. Author :
        Farouc A. Jaffer, Peter Libby and Ralph Weissleder
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Arteriosclerosis, Thrombosis, and Vascular Biology
      6. Products :
      7. Volume :
        29
      8. Issue :
        7
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        In vivo imaging; fluorescence molecular tomography; FMT; ProSense; OsteoSense; atherosclerosis; molecular imaging; optical, fluorescence; multimodality; nanoparticle
      12. Abstract :
        Imaging approaches that visualize molecular targets rather than anatomic structures aim to illuminate vital molecular and cellular aspects of atherosclerosis biology in vivo. Several such molecular imaging strategies stand ready for rapid clinical application. This review describes the growing role of in vivo optical molecular imaging in atherosclerosis and highlights its ability to visualize atheroma inflammation, calcification, and angiogenesis. In addition, we discuss advances in multimodality probes, both in the context of multimodal imaging as well as multifunctional, or “theranostic,” nanoparticles. This review highlights particular molecular imaging strategies that possess strong potential for clinical translation.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2733228/?tool=pubmed
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4642
      1. Author :
        Wallis de Vries BM, van Dam GM, Tio RA, Hillebrands JL, Slart RH and Zeebregts CJ
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2008
      5. Publication :
        Journal of Vascular Surgery
      6. Products :
      7. Volume :
        48
      8. Issue :
        6
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        In vivo imaging; MMPSense; atherosclerotic carotid plaque
      12. Abstract :
        BACKGROUND: There is increasing evidence that plaque vulnerability, rather than the degree of stenosis, is important in predicting the occurrence of subsequent cerebral ischemic events in patients with carotid artery stenosis. The many imaging modalities currently available have different properties with regard to the visualization of the extent of vulnerability in carotid plaque formation.

        METHODS: Original published studies were identified using the MEDLINE database (January 1966 to March 2008). Manual cross-referencing was also performed.

        RESULTS: There is no single imaging modality that can produce definitive information about the state of vulnerability of an atherosclerotic plaque. Each has its own specific drawbacks, which may be the use of ionizing radiation or nephrotoxic contrast agents, an invasive character, low patient tolerability, or simply the paucity of information obtained on plaque vulnerability. Functional molecular imaging techniques such as positron emission tomography (PET), single photon emission-computed tomography (SPECT) and near infra-red spectroscopy (NIRS) do seem able accurately to visualize and even quantify features of plaque vulnerability and its pathophysiologic processes. Promising new techniques like near infra-red fluorescence imaging are being developed and may be beneficial in this field.

        CONCLUSION: There is a promising role for functional molecular imaging modalities like PET, SPECT, or NIRS related to improvement of selection criteria for carotid intervention, especially when combined with CT or MRI to add further anatomical details to molecular information. Further information will be needed to define whether and where this functional molecular imaging will fit into a clinical strategy.
      13. URL :
        http://www.jvascsurg.org/article/S0741-5214(08)01146-4/abstract
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4643
      1. Author :
        N/A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Circulation
      6. Products :
      7. Volume :
        119
      8. Issue :
        20
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        In vivo imaging; MMPSense
      12. Abstract :
        An extract of the first 250 words of the full text is provided, because this article has no abstract:

        Formation of unstable atherosclerotic plaque in the internal carotid artery carries a high risk for emboli and subsequent cerebral ischemic events. The fibrous cap of such a plaque may become thin and rupture as a result of the depletion of matrix components through the activation of proteolytic enzymes such as matrix-degrading proteinases. Enhanced matrix breakdown has been attributed primarily to a family of matrix-degrading metalloproteinases (MMPs) that are highly concentrated in atherosclerotic plaques by inflammatory cells (eg, macrophages, foam cells), smooth muscle cells and endothelial cells.

        Elevated serum MMP-9 concentration is associated with carotid plaque instability and the presence of infiltrated macrophages. Furthermore, analysis of the presence of MMP-9 protein by ELISA within excised carotid plaques revealed high MMP-9 protein mass in calcified segments at or near the carotid bifurcation and in segments with intraplaque hemorrhage. Gelatin zymography showed an increased gelatinase activity of MMP-9 in these segments. These data favor the important role of MMP-9 in the pathogenesis of plaque instability. We analyzed the topographic distribution of MMPs within an excised human carotid plaque by applying multispectral near-infrared fluorescence (NIRF) imaging (IVIS Spectrum, Caliper Life Sciences, Hopkinton, Mass).

        A surgical endarterectomy was performed on a 74-year-old women with a left-sided, symptomatic, >70% carotid stenosis. Immediately after endarterectomy, the plaque was placed in PBS and transported to the NIRF system. The plaque was then stretched out and fixed on a silicon plate with 25G needles. A PBS NIRF image was generated from both the intraluminal and extraluminal side of the . . .
      13. URL :
        http://circ.ahajournals.org/cgi/content/extract/119/20/e534
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4644
      1. Author :
        Jason R. McCarthy, Purvish Patel, Ion Botnaru, Pouneh Haghayeghi, Ralph Weissleder and Farouc A. Jaffer
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2009
      5. Publication :
        Bioconjugate Chemistry
      6. Products :
      7. Volume :
        20
      8. Issue :
        6
      9. Page Numbers :
        N/A
      10. Research Area :
        Cardiovascular Research
      11. Keywords :
        In vivo imaging; thrombi; VivoTag
      12. Abstract :
        Thrombosis underlies numerous life-threatening cardiovascular syndromes. Development of thrombosis-specific molecular imaging agents to detect and monitor thrombogenesis and fibrinolysis in vivo could improve the diagnosis, risk stratification, and treatment of thrombosis syndromes. To this end, we have synthesized efficient multimodal nanoagents targeted to two different constituents of thrombi, namely, fibrin and activated factor XIII. These agents are targeted via the conjugation of peptide-targeting ligands to the surface of fluorescently labeled magnetic nanoparticles. As demonstrated by in vitro and in vivo studies, both nanoagents possess high affinities for thrombi, and enable mutimodal fluorescence and magnetic resonance imaging.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/19456115
      14. Call Number :
        PKI @ sarah.piper @
      15. Serial :
        4647
Back to Search
Select All  |  Deselect All