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The Relationship Of Cyclic Amp Levels And Collagen Synthesis In Vascular Smooth Muscle Cells Following Estrogen Or Beta-Adrenergic Treatment, George John Dimopoulos

Doctoral Dissertations

The use of estrogens in postmenopausal women has become controversial. Estrogen replacement therapy has been used for many years to slow the progression of atherosclerosis. However, recent clinical studies have shown that menopausal women on hormone replacement therapy have higher incidences of myocardial infarctions and strokes than their counterparts without the therapy. Other studies have demonstrated that a decrease in collagen content in advanced atherosclerotic lesions may weaken the structural integrity of these lesions, resulting in rupture and clot formation. Within lesions, vascular smooth muscle cells (VSMCs) actively synthesize collagen and other types of extracellular matrix proteins during atherogenesis. Estrogen, …

Spatial Properties Of Photophobia, James Michael Stringham

Doctoral Dissertations

The squint response corresponding to photophobia (light-induced discomfort) was assessed via electromyography as a function of stimulus size, retinal locus (superior, inferior, temporal, nasal), and retinal eccentricity in three subjects. These results were compared to the same subjects' psychophysically-determined spatial distributions of macular pigment, to examine in detail the attenuation of photophobia by macular pigment. Results indicate that the photophobia response is preferentially biased to prevent the fovea from exposure to potentially damaging short-wavelength light. In this regard, macular pigment appears to act as a spatially-integrated filter, serving to attenuate photophobia to a great extent. Photophobia and macular pigment therefore …

Hydrodynamic Behavior And Thermal Stability Of A Pegylated Protein: Studies With Hen Egg Lysozyme, Yatin R. Gokarn

Doctoral Dissertations

We studied the effect of covalent attachment of polyethylene glycol (PEGylation) on the hydrodynamic behavior and thermal stability of a model protein---Hen Egg Lysozyme (HEL). HEL was modified with a linear, 20-kD, PEG to produce mono (PEG1-HEL), di (PEG2-HEL), and triPEGylated (PEG3-HEL) species.

The hydrodynamic properties of HEL were altered upon PEGylation. A decrease in sedimentation (s) and diffusion (D) coefficients was observed for all three PEG-HEL molecules in comparison to HEL (1.81 s). Despite differences in molecular weights of the PEG-HEL molecules (∼34, 55 and 80 kD), their s values were very close (1.0--1.1 s). Significant hydrodynamic non-ideality was …