Graduation Year


Date of Thesis Acceptance

Fall 5-10-2011

Major Department or Program

Biochemistry, Biophysics and Molecular Biology


Doug Juers


Pulmonary Hypertension (PH) is a disease marked by abnormally hig h blood pressure in the pulmonary circulation. The disease often causes death from right heart failure as a result of the greatly increased cardiac load. Pulmonary vascular stiffening has been shown to contribute to up to 30 - 40% of the increased cardiac load seen in PH patients. Extracellular matrix proteins collagen and elastin, proven players in the pathology of pulmonary hypertension, have also been proven to contribute to the stiffness of large elastic arteries. We examined the relationship of three specific structural properties of collagen, the tortuocity locking stretch, orientation, and total locking stretch, to stiffening in bovine main pulmonary arteries. We investigated locking stretch by imaging collagen using Second Harmonic Generation (SHG ). Locking stretches and orientations of collagen fibers were measured from SHG images using a MATLAB based image processing program. We sought to validate this method by comparing its results to data from hand tracing collagen fibers. The data produced by these two methods did not match, and thus we failed to validate our MATLAB based image processing method. However we have shown the hand tracing method to be considerably flawed, casting doubt on the validity of that data. In the future we hope to va lidate the MATLAB based method by analyzing a series of random sine curves of known locking stretch and orientation. Once our method has been validated we can begin to examine the relationship between collagen structure and pulmonary vascular stiffening i n patients with pulmonary hypertension.

Page Count


Subject Headings

Pulmonary hypertension -- Diagnosis‚ Pulmonary hypertension -- Classification‚ Hypertension -- Research -- United States‚ Arteries -- Diseases -- Etiology‚ Arteries -- Elastic properties‚ Collagen -- Structure‚ Cattle -- Anatomy and histology‚ Computer-Assisted Image Processing -- Instrumentation -- Methods‚ Ultrastructure (Biology) -- Examinations and questions‚ MATLAB‚ Whitman College -- Dissertation collection 2011 -- Biochemistry‚ Biophysics‚ and Molecular Biology

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Public Accessible Thesis

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