Spelling suggestions: "subject:"smooth muscle."" "subject:"amooth muscle.""
291 |
Airway smooth muscle dynamicsIJpma, Gijs January 2010 (has links)
The current study aims to investigate the relative contributions of each of the processes that govern airway smooth muscle mechanical behaviour. Studies have shown that breathing dynamics have a substantial effect on airway constriction in healthy and diseased subjects, yet little is known about the dynamic response of the main instigator of airway constriction, Airway Smooth Muscle (ASM). In this work several models are developed to further the understanding of ASM dynamics, particularly the roles and interactions of the three dominant processes in the muscle: contractile dynamics, length adaptation and passive dynamics. Three individual models have been developed, each describing a distinct process or structure within the muscle. The first is a contractile model which describes the contractile process and the influence of external excitation on contractile behaviour. The second model incorporates the contractile model to describe length adaptation, which includes the reorganisation and polymerisation of contractile elements in response to length changes. The third model describes the passive behaviour of the muscle, which entails the mechanical behaviour of all non-contractile components and processes. As little data on the passive dynamics of the muscle was available in the literature, a number of experiments were conducted to investigate relaxed ASM dynamics. The experimental data and mathematical modelling showed that passive dynamics plays not only a dominant role in relaxed ASM, but contributes considerably to the dynamics of contracted muscle as well. A novel theory of sequential multiplication in passive ASM is proposed and implemented in a mathematical model. Experiments and literature validated the model simulations. Further integration of the models and improved force control modelling of length adaptation is proposed for future study. It is likely that the coupling of the models presented here with models describing other airway wall components will provide a more complete picture of airway dynamics, which will be invaluable for understanding respiratory disease.
|
292 |
Airway smooth muscle response to vibrationsDu, Youhua January 2006 (has links)
The main goal of this research was the in vitro investigation of the stiffness response of contracted airway smooth muscles under different external oscillations. Living animal airway smooth muscle tissues were dissected from pig tracheas and stimulated by a chemical stimulus (acetylcholine). These tissues were then systematically excited with different external vibrations. The force change was recorded to reflect the muscle stiffness change under vibration. The static and dynamic stiffness of contracted airway smooth muscles in isometric contraction were determined before, during and after vibrations. A continuum cross-bridge dynamic model (the fading memory model) was modified to accommodate smooth muscle behaviour and dynamically describes the cross-bridge kinetics. A two-dimensional finite element model (FEM) was developed to simulate longitudinal and transverse vibrations of the tissue. An empirical equation, derived from the experiments, is incorporated into the FEM. The results indicate that the stiffness of active smooth muscles can be physically reduced using external vibrations. This reduction is caused by a certain physical position change between actin and myosin. The dynamic stiffness has the tendency of decreasing as the frequency and/or amplitude of external vibration increases. However, the static stiffness decreases with an increase in the frequency and amplitude of excitation until it reaches a critical value of frequency where no variation in stiffness is observed. It is postulated that the tissue elasticity and mass inertia are the main contributors to the dynamic stiffness while the actin-myosin cross-bridge cycling is the main contributor to the static stiffness.
|
293 |
Nerve-induced release of nitric oxide in gastrointestinal and erectile tissue /Hallén, Katarina, January 2004 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.
|
294 |
On cellular sources for intimal hyperplasia after vascular interventions /Mellander, Stefan, January 2007 (has links)
Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2007. / Härtill 4 uppsatser.
|
295 |
Coronary artery reactivity in diabetes mellitusDick, Gregory M. January 1996 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves: 106-117). Also available on the Internet.
|
296 |
Role of the intermediate-conductance Ca²⁺-activated K⁺ channel (K[ca]3.1) in coronary smooth muscle cell phenotypic modulationTharp, Darla L., January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Vita. "December 2007" Includes bibliographical references.
|
297 |
Novel genes associated with airway smooth muscle proliferation in asthmaLau, Justine Y. January 2008 (has links)
Thesis (Ph. D.)--University of Sydney, 2009. / Title from title screen (viewed Aug. 11, 2009) Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Discipline of Pharmacology, Faculty of Medicine. Degree awarded 2009; thesis submitted 2008. Includes bibliographical references. Also available in print form.
|
298 |
The influence of PAR activators on allergen-induced pulmonary eosinophilia and hyperresponsiveness in mice /De Campo, Benjamin. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2008.
|
299 |
Mechanistic analysis of SRF and the myocardin family of coactivators during muscle developmentLi, Shijie. January 2005 (has links)
Thesis (Ph.D.) -- University of Texas Southwestern Medical Center at Dallas, 2005. / Embargoed. Vita. Bibliography: References located at the end of each chapter.
|
300 |
The sympathetic cotransmitters neuropeptide Y and ATP in the regulation of the vascular smooth muscle cell mitogenic effects, receptors and second messengers : aspects on clinical patophysiology /Erlinge, David. January 1994 (has links)
Thesis (doctoral)--Lund University, 1994. / Added t.p. with thesis statement inserted.
|
Page generated in 0.0282 seconds