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  1. Article: Microcalcifications, Their Genesis, Growth, and Biomechanical Stability in Fibrous Cap Rupture.

    Cardoso, Luis / Weinbaum, Sheldon

    Advances in experimental medicine and biology

    2018  Volume 1097, Page(s) 129–155

    Abstract: For many decades, cardiovascular calcification has been considered as a passive process, accompanying atheroma progression, correlated with plaque burden, and apparently without a major role on plaque vulnerability. Clinical and pathological analyses ... ...

    Abstract For many decades, cardiovascular calcification has been considered as a passive process, accompanying atheroma progression, correlated with plaque burden, and apparently without a major role on plaque vulnerability. Clinical and pathological analyses have previously focused on the total amount of calcification (calcified area in a whole atheroma cross section) and whether more calcification means higher risk of plaque rupture or not. However, this paradigm has been changing in the last decade or so. Recent research has focused on the presence of microcalcifications (μCalcs) in the atheroma and more importantly on whether clusters of μCalcs are located in the cap of the atheroma. While the vast majority of μCalcs are found in the lipid pool or necrotic core, they are inconsequential to vulnerable plaque. Nevertheless, it has been shown that μCalcs located within the fibrous cap could be numerous and that they behave as an intensifier of the background circumferential stress in the cap. It is now known that such intensifying effect depends on the size and shape of the μCalc as well as the proximity between two or more μCalcs. If μCalcs are located in caps with very low background stress, the increase in stress concentration may not be sufficient to reach the rupture threshold. However, the presence of μCalc(s) in the cap with a background stress of about one fifth to one half the rupture threshold (a stable plaque) will produce a significant increase in local stress, which may exceed the cap rupture threshold and thus transform a non-vulnerable plaque into a vulnerable one. Also, the classic view that treats cardiovascular calcification as a passive process has been challenged, and emerging data suggest that cardiovascular calcification may encompass both passive and active processes. The passive calcification process comprises biochemical factors, specifically circulating nucleating complexes, which would lead to calcification of the atheroma. The active mechanism of atherosclerotic calcification is a cell-mediated process via cell death of macrophages and smooth muscle cells (SMCs) and/or the release of matrix vesicles by SMCs.
    MeSH term(s) Atherosclerosis/pathology ; Calcinosis/pathology ; Fibrosis ; Humans ; Necrosis ; Plaque, Atherosclerotic/pathology
    Language English
    Publishing date 2018-10-12
    Publishing country United States
    Document type Journal Article ; Review
    ISSN 2214-8019 ; 0065-2598
    ISSN (online) 2214-8019
    ISSN 0065-2598
    DOI 10.1007/978-3-319-96445-4_7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Fulfilling the dream: the importance of doing what you believe and being taken seriously. BMES Inaugural Diversity Award and Lecture: BMES Annual Meeting, October 10, 2009.

    Weinbaum, Sheldon

    Annals of biomedical engineering

    2010  Volume 38, Issue 3, Page(s) 1132–1140

    Abstract: In this Inaugural Diversity Lecture I trace the diversity struggles in my own life over the past 46 years since the historic 1963 "I Have a Dream" speech of Martin Luther King, which has changed this nation forever. After a brief personal history, the ... ...

    Abstract In this Inaugural Diversity Lecture I trace the diversity struggles in my own life over the past 46 years since the historic 1963 "I Have a Dream" speech of Martin Luther King, which has changed this nation forever. After a brief personal history, the paper is divided into three major parts; "My consciousness raising years", "Fulfilling the dream", and NIH Minority Scholars Program. The paper ends with some concluding thoughts on the importance of being taken seriously.
    MeSH term(s) Biomedical Engineering/history ; Cultural Diversity ; History, 20th Century ; History, 21st Century ; Industry/history ; New York
    Language English
    Publishing date 2010-03-20
    Publishing country United States
    Document type Historical Article ; Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 185984-5
    ISSN 1573-9686 ; 0191-5649 ; 0090-6964
    ISSN (online) 1573-9686
    ISSN 0191-5649 ; 0090-6964
    DOI 10.1007/s10439-009-9893-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: A Lifetime Achievement in Bioengineering: Professor Shu Chien.

    Weinbaum, Sheldon / Li, Yi-Shuan Julie / Schmid-Schönbein, Geert W

    Annals of biomedical engineering

    2019  Volume 47, Issue 11, Page(s) 2147–2150

    MeSH term(s) Bioengineering/history ; Hemodynamics ; History, 20th Century ; History, 21st Century ; Mechanotransduction, Cellular ; Rheology
    Language English
    Publishing date 2019-10-24
    Publishing country United States
    Document type Biography ; Editorial ; Historical Article ; Portrait
    ZDB-ID 185984-5
    ISSN 1573-9686 ; 0191-5649 ; 0090-6964
    ISSN (online) 1573-9686
    ISSN 0191-5649 ; 0090-6964
    DOI 10.1007/s10439-019-02390-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: The Glycocalyx and Its Role in Vascular Physiology and Vascular Related Diseases.

    Weinbaum, Sheldon / Cancel, Limary M / Fu, Bingmei M / Tarbell, John M

    Cardiovascular engineering and technology

    2020  Volume 12, Issue 1, Page(s) 37–71

    Abstract: ... of the endothelial glycocalyx layer (Weinbaum in Annu Rev Biomed Eng 9:121-167, 2007). Since then there has been ... the new formulation of the century old Starling principle, now referred to as the Michel-Weinbaum ...

    Abstract Purpose: In 2007 the two senior authors wrote a review on the structure and function of the endothelial glycocalyx layer (Weinbaum in Annu Rev Biomed Eng 9:121-167, 2007). Since then there has been an explosion of interest in this hydrated gel-like structure that coats the luminal surface of endothelial cells that line our vasculature due to its important functions in (A) basic vascular physiology and (B) vascular related diseases. This review will highlight the major advances that have occurred since our 2007 paper.
    Methods: A literature search mainly focusing on the role of the glycocalyx in the two major areas described above was performed using electronic databases.
    Results: In part (A) of this review, the new formulation of the century old Starling principle, now referred to as the Michel-Weinbaum glycoclayx model or revised Starling hypothesis, is described including new subtleties and physiological ramifications. New insights into mechanotransduction and release of nitric oxide due to fluid shear stress sensed by the glycocalyx are elaborated. Major advances in understanding the organization and function of glycocalyx components, and new techniques for measuring both its thickness and spatio-chemical organization based on super resolution, stochastic optical reconstruction microscopy (STORM) are presented. As discussed in part (B) of this review, it is now recognized that artery wall stiffness associated with hypertension and aging induces glycocalyx degradation, endothelial dysfunction and vascular disease. In addition to atherosclerosis and cardiovascular diseases, the glycocalyx plays an important role in lifestyle related diseases (e.g., diabetes) and cancer. Infectious diseases including sepsis, Dengue, Zika and Corona viruses, and malaria also involve the glycocalyx. Because of increasing recognition of the role of the glycocalyx in a wide range of diseases, there has been a vigorous search for methods to protect the glycocalyx from degradation or to enhance its synthesis in disease environments.
    Conclusion: As we have seen in this review, many important developments in our basic understanding of GCX structure, function and role in diseases have been described since the 2007 paper. The future is wide open for continued GCX research.
    MeSH term(s) Atherosclerosis ; Cardiovascular Diseases ; Endothelial Cells ; Glycocalyx ; Humans ; Mechanotransduction, Cellular ; Zika Virus ; Zika Virus Infection
    Keywords covid19
    Language English
    Publishing date 2020-09-21
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Review
    ZDB-ID 2543111-0
    ISSN 1869-4098 ; 1869-408X
    ISSN (online) 1869-4098
    ISSN 1869-408X
    DOI 10.1007/s13239-020-00485-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: The effect of plaque morphology, material composition and microcalcifications on the risk of cap rupture: A structural analysis of vulnerable atherosclerotic plaques.

    Corti, Andrea / De Paolis, Annalisa / Grossman, Pnina / Dinh, Phuc A / Aikawa, Elena / Weinbaum, Sheldon / Cardoso, Luis

    Frontiers in cardiovascular medicine

    2022  Volume 9, Page(s) 1019917

    Abstract: Background: The mechanical rupture of an atheroma cap may initiate a thrombus formation, followed by an acute coronary event and death. Several morphology and tissue composition factors have been identified to play a role on the mechanical stability of ... ...

    Abstract Background: The mechanical rupture of an atheroma cap may initiate a thrombus formation, followed by an acute coronary event and death. Several morphology and tissue composition factors have been identified to play a role on the mechanical stability of an atheroma, including cap thickness, lipid core stiffness, remodeling index, and blood pressure. More recently, the presence of microcalcifications (μCalcs) in the atheroma cap has been demonstrated, but their combined effect with other vulnerability factors has not been fully investigated.
    Materials and methods: We performed numerical simulations on 3D idealized lesions and a microCT-derived human coronary atheroma, to quantitatively analyze the atheroma cap rupture. From the predicted cap stresses, we defined a biomechanics-based vulnerability index (VI) to classify the impact of each risk factor on plaque stability, and developed a predictive model based on their synergistic effect.
    Results: Plaques with low remodeling index and soft lipid cores exhibit higher VI and can shift the location of maximal wall stresses. The VI exponentially rises as the cap becomes thinner, while the presence of a μCalc causes an additional 2.5-fold increase in vulnerability for a spherical inclusion. The human coronary atheroma model had a stable phenotype, but it was transformed into a vulnerable plaque after introducing a single spherical μCalc in its cap. Overall, cap thickness and μCalcs are the two most influential factors of mechanical rupture risk.
    Conclusions: Our findings provide supporting evidence that high risk lesions are non-obstructive plaques with softer (lipid-rich) cores and a thin cap with μCalcs. However, stable plaques may still rupture in the presence of μCalcs.
    Language English
    Publishing date 2022-10-06
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2781496-8
    ISSN 2297-055X
    ISSN 2297-055X
    DOI 10.3389/fcvm.2022.1019917
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: In Memoriam: Shmuel Einav, 1942-2022.

    Bluestein, Danny / Dewey, C Forbes / Elad, David / Gharib, Morteza Mory / Kamm, Roger D / Lieber, Barry B / Margulies, Susan S / Slepian, Marvin J / Tarbell, John / Weinbaum, Sheldon Shelly

    Journal of biomechanical engineering

    2022  Volume 144, Issue 8

    Language English
    Publishing date 2022-06-14
    Publishing country United States
    Document type Journal Article
    ZDB-ID 243094-0
    ISSN 1528-8951 ; 0148-0731
    ISSN (online) 1528-8951
    ISSN 0148-0731
    DOI 10.1115/1.4054797
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Regulation of glomerulotubular balance: flow-activated proximal tubule function.

    Wang, Tong / Weinbaum, Sheldon / Weinstein, Alan M

    Pflugers Archiv : European journal of physiology

    2017  Volume 469, Issue 5-6, Page(s) 643–654

    Abstract: The purpose of this review is to summarize our knowledge and understanding of the physiological importance and the mechanisms underlying flow-activated proximal tubule transport. Since the earliest micropuncture studies of mammalian proximal tubule, it ... ...

    Abstract The purpose of this review is to summarize our knowledge and understanding of the physiological importance and the mechanisms underlying flow-activated proximal tubule transport. Since the earliest micropuncture studies of mammalian proximal tubule, it has been recognized that tubular flow is an important regulator of sodium, potassium, and acid-base transport in the kidney. Increased fluid flow stimulates Na
    MeSH term(s) Animals ; Glomerular Filtration Rate ; Humans ; Kidney Tubules, Proximal/metabolism ; Kidney Tubules, Proximal/physiology ; Renal Reabsorption ; Sodium-Hydrogen Exchanger 3/genetics ; Sodium-Hydrogen Exchanger 3/metabolism ; Sodium-Potassium-Exchanging ATPase/genetics ; Sodium-Potassium-Exchanging ATPase/metabolism
    Chemical Substances Sodium-Hydrogen Exchanger 3 ; Sodium-Potassium-Exchanging ATPase (EC 3.6.3.9)
    Language English
    Publishing date 2017-03-07
    Publishing country Germany
    Document type Journal Article ; Review ; Research Support, N.I.H., Extramural
    ZDB-ID 6380-0
    ISSN 1432-2013 ; 0031-6768
    ISSN (online) 1432-2013
    ISSN 0031-6768
    DOI 10.1007/s00424-017-1960-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Fulfilling the Dream: The Importance of Doing What You Believe and Being Taken Seriously

    Weinbaum, Sheldon

    Annals of biomedical engineering. 2010 Mar., v. 38, no. 3

    2010  

    Abstract: In this Inaugural Diversity Lecture I trace the diversity struggles in my own life over the past 46 years since the historic 1963 “I Have a Dream” speech of Martin Luther King, which has changed this nation forever. After a brief personal history, the ... ...

    Abstract In this Inaugural Diversity Lecture I trace the diversity struggles in my own life over the past 46 years since the historic 1963 “I Have a Dream” speech of Martin Luther King, which has changed this nation forever. After a brief personal history, the paper is divided into three major parts; “My consciousness raising years”, “Fulfilling the dream”, and NIH Minority Scholars Program. The paper ends with some concluding thoughts on the importance of being taken seriously.
    Language English
    Dates of publication 2010-03
    Size p. 1132-1140.
    Publisher Springer US
    Publishing place Boston
    Document type Article
    ZDB-ID 185984-5
    ISSN 1573-9686 ; 0191-5649 ; 0090-6964
    ISSN (online) 1573-9686
    ISSN 0191-5649 ; 0090-6964
    DOI 10.1007/s10439-009-9893-9
    Database NAL-Catalogue (AGRICOLA)

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  9. Article ; Online: Flow-activated proximal tubule function underlies glomerulotubular balance.

    Du, Zhaopeng / Duan, Yi / Yan, QingShang / Weinbaum, Sheldon / Weinstein, Alan M / Wang, Tong

    The Kitasato medical journal

    2019  Volume 46, Issue 1, Page(s) 105–117

    Abstract: Flow-modulated salt and water transport in proximal tubules has been recognized for more than four decades. Recent work has made major progress in defining the underlying cellular mechanisms. First, we demonstrated that perfusion-absorption balance is ... ...

    Abstract Flow-modulated salt and water transport in proximal tubules has been recognized for more than four decades. Recent work has made major progress in defining the underlying cellular mechanisms. First, we demonstrated that perfusion-absorption balance is present in the isolated perfused proximal tubule of the mouse kidney, and thus is independent of neuronal control and systemic hormonal regulation. In proximal tubule, higher axial flow rates stimulate sodium and bicarbonate absorption by increased apical membrane Na
    Language English
    Publishing date 2019-04-03
    Publishing country Japan
    Document type Journal Article
    ISSN 2187-9699
    ISSN (online) 2187-9699
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Changing views of the biomechanics of vulnerable plaque rupture: a review.

    Cardoso, Luis / Weinbaum, Sheldon

    Annals of biomedical engineering

    2013  Volume 42, Issue 2, Page(s) 415–431

    Abstract: This review examines changing perspectives on the biomechanics of vulnerable plaque rupture over the past 25 years from the first finite element analyses (FEA) showing that the presence of a lipid pool significantly increases the local tissue stress in ... ...

    Abstract This review examines changing perspectives on the biomechanics of vulnerable plaque rupture over the past 25 years from the first finite element analyses (FEA) showing that the presence of a lipid pool significantly increases the local tissue stress in the atheroma cap to the latest imaging and 3D FEA studies revealing numerous microcalcifications in the cap proper and a new paradigm for cap rupture. The first part of the review summarizes studies describing the role of the fibrous cap thickness, tissue properties, and lesion geometry as main determinants of the risk of rupture. Advantages and limitations of current imaging technologies for assessment of vulnerable plaques are also discussed. However, the basic paradoxes as to why ruptures frequently did not coincide with location of PCS and why caps >65 μm thickness could rupture at tissue stresses significantly below the 300 kPa critical threshold still remained unresolved. The second part of the review describes recent studies in the role of microcalcifications, their origin, shape, and clustering in explaining these unresolved issues including the actual mechanism of rupture due to the explosive growth of tiny voids (cavitation) in local regions of high stress concentration between closely spaced microinclusions oriented along their tensile axis.
    MeSH term(s) Animals ; Biomechanical Phenomena ; Humans ; Plaque, Atherosclerotic/metabolism ; Plaque, Atherosclerotic/pathology ; Plaque, Atherosclerotic/physiopathology ; Rupture, Spontaneous ; Stress, Physiological
    Language English
    Publishing date 2013-07-11
    Publishing country United States
    Document type Journal Article ; Research Support, American Recovery and Reinvestment Act ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S. ; Review
    ZDB-ID 185984-5
    ISSN 1573-9686 ; 0191-5649 ; 0090-6964
    ISSN (online) 1573-9686
    ISSN 0191-5649 ; 0090-6964
    DOI 10.1007/s10439-013-0855-x
    Database MEDical Literature Analysis and Retrieval System OnLINE

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