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  1. Article ; Online: Persistent non-homeostatic remodeling of aortic collagen following a brief episode of hypertension: A computational study.

    Irons, Linda / Cavinato, Cristina / Humphrey, Jay D

    Journal of the mechanical behavior of biomedical materials

    2023  Volume 144, Page(s) 105966

    Abstract: The healthy adult aorta exhibits a remarkable homeostatic ability to respond to sustained changes in hemodynamic loads under many circumstances, but this mechanical homeostasis can be compromised or lost in natural aging and diverse pathological ... ...

    Abstract The healthy adult aorta exhibits a remarkable homeostatic ability to respond to sustained changes in hemodynamic loads under many circumstances, but this mechanical homeostasis can be compromised or lost in natural aging and diverse pathological processes. Herein, we investigate persistent non-homeostatic changes in the composition and mechanical properties of the thoracic aorta in adult wild-type mice following 14 days of angiotensin II-induced hypertension. We employ a multiscale computational model of arterial growth and remodeling driven by mechanosensitive and angiotensin II-related cell signaling pathways. We find that experimentally observed findings can only be recapitulated computationally if the collagen deposited during the transient period of hypertension has altered properties (deposition stretch, fiber angle, crosslinking) compared with the collagen produced in the original homeostatic state. Some of these changes are predicted to persist for at least six months after blood pressure is restored to normal levels, consistent with the experimental findings.
    MeSH term(s) Mice ; Animals ; Angiotensin II/adverse effects ; Angiotensin II/metabolism ; Hypertension ; Aorta/pathology ; Collagen/metabolism ; Aorta, Thoracic ; Homeostasis
    Chemical Substances Angiotensin II (11128-99-7) ; Collagen (9007-34-5)
    Language English
    Publishing date 2023-06-07
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2378381-3
    ISSN 1878-0180 ; 1751-6161
    ISSN (online) 1878-0180
    ISSN 1751-6161
    DOI 10.1016/j.jmbbm.2023.105966
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: World Health Organization Guidelines on Medicines for Diabetes Treatment Intensification.

    Kansagara, Devan / Humphrey, Linda L / Qaseem, Amir

    Annals of internal medicine

    2019  Volume 170, Issue 8, Page(s) 583–584

    MeSH term(s) Diabetes Mellitus, Type 2 ; Humans ; Hypoglycemic Agents ; World Health Organization
    Chemical Substances Hypoglycemic Agents
    Language English
    Publishing date 2019-03-28
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/L19-0069
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Update Alert: Use of N95, Surgical, or Cloth Masks to Prevent COVID-19 in Health Care and Community Settings: Living Practice Points From the American College of Physicians (Version 1).

    Qaseem, Amir / Etxeandia-Ikobaltzeta, Itziar / Yost, Jennifer / Humphrey, Linda L

    Annals of internal medicine

    2020  Volume 173, Issue 12, Page(s) 170

    MeSH term(s) COVID-19 ; Delivery of Health Care ; Humans ; Masks ; Physicians ; SARS-CoV-2 ; United States
    Keywords covid19
    Language English
    Publishing date 2020-10-27
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/L20-1268
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Update Alert 2: Should Clinicians Use Chloroquine or Hydroxychloroquine Alone or in Combination With Azithromycin for the Prophylaxis or Treatment of COVID-19? Living Practice Points From the American College of Physicians.

    Qaseem, Amir / Yost, Jennifer / Etxeandia-Ikobaltzeta, Itziar / Humphrey, Linda L

    Annals of internal medicine

    2020  Volume 173, Issue 5, Page(s) W88–W89

    MeSH term(s) Azithromycin ; Betacoronavirus ; COVID-19 ; Chloroquine ; Coronavirus Infections/drug therapy ; Coronavirus Infections/epidemiology ; Humans ; Hydroxychloroquine ; Pandemics ; Pneumonia, Viral/epidemiology ; SARS-CoV-2 ; United States ; COVID-19 Drug Treatment
    Chemical Substances Hydroxychloroquine (4QWG6N8QKH) ; Azithromycin (83905-01-5) ; Chloroquine (886U3H6UFF)
    Keywords covid19
    Language English
    Publishing date 2020-07-30
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/L20-1007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Should Remdesivir Be Used for the Treatment of Patients With COVID-19? Rapid, Living Practice Points From the American College of Physicians (Version 2, Update Alert 3).

    Qaseem, Amir / Yost, Jennifer / Etxeandia-Ikobaltzeta, Itziar / Abraham, George M / Jokela, Janet A / Forciea, Mary Ann / Miller, Matthew C / Humphrey, Linda L

    Annals of internal medicine

    2022  Volume 175, Issue 5, Page(s) W55–W57

    MeSH term(s) Adenosine Monophosphate/analogs & derivatives ; Adenosine Monophosphate/therapeutic use ; Alanine/analogs & derivatives ; Antiviral Agents/adverse effects ; COVID-19/drug therapy ; Humans ; Physicians
    Chemical Substances Antiviral Agents ; remdesivir (3QKI37EEHE) ; Adenosine Monophosphate (415SHH325A) ; Alanine (OF5P57N2ZX)
    Language English
    Publishing date 2022-03-01
    Publishing country United States
    Document type Letter
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/M21-4810
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Intracellular signaling control of mechanical homeostasis in the aorta.

    Irons, Linda / Estrada, Ana C / Humphrey, Jay D

    Biomechanics and modeling in mechanobiology

    2022  Volume 21, Issue 5, Page(s) 1339–1355

    Abstract: Mature arteries exhibit a preferred biomechanical state in health evidenced by a narrow range of intramural and wall shear stresses. When stresses are perturbed by changes in blood pressure or flow, homeostatic mechanisms tend to restore target values ... ...

    Abstract Mature arteries exhibit a preferred biomechanical state in health evidenced by a narrow range of intramural and wall shear stresses. When stresses are perturbed by changes in blood pressure or flow, homeostatic mechanisms tend to restore target values via altered contractility and/or cell and matrix turnover. In contrast, vascular disease associates with compromised homeostasis, hence we must understand mechanisms underlying mechanical homeostasis and its robustness. Here, we use a multiscale computational model wherein mechanosensitive intracellular signaling pathways drive arterial growth and remodeling. First, we identify an ensemble of cell-level parameterizations where tissue-level responses are well-regulated and adaptive to hemodynamic perturbations. The responsible mechanism is persistent multiscale negative feedback whereby mechanosensitive signaling drives mass turnover until homeostatic target stresses are reached. This demonstrates how robustness emerges despite inevitable cell and individual heterogeneity. Second, we investigate tissue-level effects of signaling node knockdowns (ATIR, ROCK, TGF[Formula: see text]RII, PDGFR, ERK1/2) and find general agreement with experimental reports of fault tolerance. Robustness against structural changes manifests via low engagement of the node under baseline stresses or compensatory multiscale feedback via upregulation of additional pathways. Third, we show how knockdowns affect collagen and smooth muscle turnover at baseline and with perturbed stresses. In several cases, basal production is not remarkably affected, but sensitivities to stress deviations, which influence feedback strength, are reduced. Such reductions can impair adaptive responses, consistent with previously reported aortic vulnerability despite grossly normal appearances. Reduced stress sensitivities thus form a candidate mechanism for how robustness is lost, enabling transitions from health towards disease.
    MeSH term(s) Aorta ; Arteries/physiology ; Stress, Mechanical ; Homeostasis ; Blood Pressure/physiology
    Language English
    Publishing date 2022-07-22
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2093052-5
    ISSN 1617-7940 ; 1617-7959
    ISSN (online) 1617-7940
    ISSN 1617-7959
    DOI 10.1007/s10237-022-01593-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Cell signaling model for arterial mechanobiology.

    Irons, Linda / Humphrey, Jay D

    PLoS computational biology

    2020  Volume 16, Issue 8, Page(s) e1008161

    Abstract: Arterial growth and remodeling at the tissue level is driven by mechanobiological processes at cellular and sub-cellular levels. Although it is widely accepted that cells seek to promote tissue homeostasis in response to biochemical and biomechanical ... ...

    Abstract Arterial growth and remodeling at the tissue level is driven by mechanobiological processes at cellular and sub-cellular levels. Although it is widely accepted that cells seek to promote tissue homeostasis in response to biochemical and biomechanical cues-such as increased wall stress in hypertension-the ways by which these cues translate into tissue maintenance, adaptation, or maladaptation are far from understood. In this paper, we present a logic-based computational model for cell signaling within the arterial wall, aiming to predict changes in extracellular matrix turnover and cell phenotype in response to pressure-induced wall stress, flow-induced wall shear stress, and exogenous sources of angiotensin II, with particular interest in mouse models of hypertension. We simulate a number of experiments from the literature at both the cell and tissue level, involving single or combined inputs, and achieve high qualitative agreement in most cases. Additionally, we demonstrate the utility of this modeling approach for simulating alterations (in this case knockdowns) of individual nodes within the signaling network. Continued modeling of cellular signaling will enable improved mechanistic understanding of arterial growth and remodeling in health and disease, and will be crucial when considering potential pharmacological interventions.
    MeSH term(s) Animals ; Arteries/physiology ; Humans ; Mice ; Models, Cardiovascular ; Signal Transduction
    Language English
    Publishing date 2020-08-24
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1008161
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Inaccuracies Describing Results of a Lung Cancer Screening Demonstration Project.

    Humphrey, Linda L / Deffebach, Mark / Midthun, David E

    JAMA internal medicine

    2017  Volume 177, Issue 9, Page(s) 1396–1397

    MeSH term(s) Early Detection of Cancer ; Humans ; Incidental Findings ; Lung Neoplasms ; Mass Screening
    Language English
    Publishing date 2017-09-05
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 2699338-7
    ISSN 2168-6114 ; 2168-6106
    ISSN (online) 2168-6114
    ISSN 2168-6106
    DOI 10.1001/jamainternmed.2017.3120
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  9. Article ; Online: Oral Pharmacologic Treatment of Type 2 Diabetes Mellitus.

    Barry, Michael J / Humphrey, Linda L / Qaseem, Amir

    Annals of internal medicine

    2017  Volume 167, Issue 1, Page(s) 75–76

    MeSH term(s) Administration, Oral ; Diabetes Mellitus, Type 2 ; Humans ; Hypoglycemic Agents ; Metformin
    Chemical Substances Hypoglycemic Agents ; Metformin (9100L32L2N)
    Language English
    Publishing date 2017--04
    Publishing country United States
    Document type Letter ; Comment
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/L17-0234
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Outpatient Treatment of Confirmed COVID-19: Living, Rapid Practice Points From the American College of Physicians (Version 2).

    Qaseem, Amir / Yost, Jennifer / Abraham, George M / Andrews, Rebecca / Jokela, Janet A / Miller, Matthew C / Humphrey, Linda L / Dunn, Andrew / Haeme, Ray / Lee, Rachael / Saini, Sameer D / Tschanz, Cdr Mark P / Etxeandia-Ikobaltzeta, Itziar / Harrod, Curtis / Shamliyan, Tatyana / Umana, Karla

    Annals of internal medicine

    2023  Volume 176, Issue 10, Page(s) 1396–1404

    MeSH term(s) Adult ; Humans ; Outpatients ; COVID-19 ; SARS-CoV-2 ; Physicians ; Antiviral Agents/therapeutic use
    Chemical Substances Antiviral Agents
    Language English
    Publishing date 2023-09-19
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 336-0
    ISSN 1539-3704 ; 0003-4819
    ISSN (online) 1539-3704
    ISSN 0003-4819
    DOI 10.7326/M23-1636
    Database MEDical Literature Analysis and Retrieval System OnLINE

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