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Full-Text Articles in Engineering
Development Of A Novel System For The Analysis Of The Cardiovascular And Autonomic Nervous Systems, Seyedmohsen Dehghanojamahalleh
Development Of A Novel System For The Analysis Of The Cardiovascular And Autonomic Nervous Systems, Seyedmohsen Dehghanojamahalleh
Theses and Dissertations
Chapter 1 - An introduction to autonomic nervous system (ANS) and cardiovascular system (CVS): The performance of the ANS can be evaluated by quantizing the changes made by the autonomic nervous system. The most common parameters that are being used in autonomic nervous system assessment tests are blood pressure, heart rate, pressure pulse wave velocity, heart rate variability, and pulse waveform. In this dissertation, we designed and developed a system that assesses the activity of these two systems. Therefore, we represented four methods to 1- evaluate the dependence of neuro- and cardiovascular systems on sex, 2- non-invasively estimate the blood …
Gene Expression Studies For Analyzing Effects Of Space Radiation In Tissues, Amatulshakoor Mohammed Farooqui
Gene Expression Studies For Analyzing Effects Of Space Radiation In Tissues, Amatulshakoor Mohammed Farooqui
Theses and Dissertations
Human exploration beyond the earth's orbit poses many risks for the crew on these missions. One of the major health risks is exposure to space radiation environment beyond the earth’s magnetic field. The space environment exposes astronauts to high levels of ionizing radiation such as galactic cosmic rays. The radiations can have acute and delayed effects on the human body. The primary response to tissue injury is increased oxidative stress and inflammation. The overall objective of this study was to analyze the effects of ionizing radiation in heart tissue by quantifying its impact on the expression of genes that correlate …
Controlling Co Dose From Corm-Loaded Electrospun Scaffolds With Diffusion-Based Modeling And Experimental Assessment Of Endothelial Cell Response, Kenyatta S. Washington
Controlling Co Dose From Corm-Loaded Electrospun Scaffolds With Diffusion-Based Modeling And Experimental Assessment Of Endothelial Cell Response, Kenyatta S. Washington
Theses and Dissertations
Cardiovascular disease (CVD) accounts for one in every five deaths in the United States alone due to occlusion in small diameter (< 6 mm) vessels. The current treatment options includes bypass grafting; however, more than 30 percent of patients do not have viable saphenous veins for autologous grafting [1]. Therefore, tissue engineering is being considered as an alternative approach. The overall goals of this project were to develop a tissue engineered vascular graft with the incorporation of carbon monoxide releasing molecules (CORMs) and to determine the impacts of carbon monoxide (CO) on endothelial cells (ECs) with the goal of promoting a functional endothelium within the graft. This was accomplished through two complementary studies: investigating the impacts of CO-loaded electrospun scaffolds on ECs for cardiovascular applications and diffusion-based modeling of drug delivery of gasotransmitters from tissue engineered scaffolds. In the first study, we extended the maximum in vitro incubation time to permit better cellular attachment and proliferation with a newly-synthesized, more hydrophobic CORM (DK3) and established the impact of CORMs on EC viability and function (e.g. reactive oxygen species (ROS) products, and ROS levels). We further investigated toxicity and biocompatibility of a newly synthesized CORM (DK4) loaded within PCL thin films and nanoparticles. We concluded that the DK4 and other compounds are not toxic at doses ranging from 0 – 50 μg/mL to the ECs both within nanoparticles that can be internalized within cells. We also conducted an in vivo pilot study to determine graft biocompatibility and preliminary results showed that CORM implants maintain mechanical integrity, support blood flow, and do not show toxicity for up to six weeks. In the second study, we validated a computational model and analyzed the output of CO delivery to better understand and control local dose. For CO release, this model is necessary because of the limitations with real-time experimental analysis and the need to better understand the dose available to the cells. We demonstrated that the validated model can be used to predict drug availability to cells for a variety of scaffolds and drug molecules. Our simulated results suggest that only a fraction of the initial concentration of gasotransmitters released from fibers that enters the interstitial fluid in vivo, or culture media in vitro, will be available to cells. We also demonstrated that fiber orientation and fiber diameter are important for drug delivery, but fiber density provides even more important information. The more contact area within the fiber scaffolds is equivalent to experimental conditions with more cell attachment and spreading. These parameters are not only important for traditional tissue engineering, but also for drug delivery. Overall, these results demonstrate the feasibility of making a tissue engineered vascular graft with the incorporation of CORMs and validating he importance of computational modeling of diffusion-based transport of CO. Future work will involve performing surface modifications to enhance cell attachment and proliferation, using the developed computational model to better predict dose available to cells, and experimentally determining impact of CO dose on ECs.
Bioprinting Of 3d Perfusable Structures Using An Extrusion-Based System, Prabhuti Kharel
Bioprinting Of 3d Perfusable Structures Using An Extrusion-Based System, Prabhuti Kharel
Theses and Dissertations
Bioprinting is a technique of creating 3D cell laden structures by accurately dispensing biomaterial to form complex synthetic tissue. Bioprinting is a process of additive manufacturing where the cell functionality and viability is preserved within the printed structure. Bioprinting is a promising alternative to produce physiologically relevant 3D structures that mimic the native tissue. However, fabrication of complex structures with vascularization has been a major challenge in bioprinting. To overcome this challenge sacrificial printing in combination with fugitive inks has been explored to create vascularize structures. The objective of this study is to fabricate hollow channels within the bioprinted structure …
Hrv - Ecg Generator: Software For Testing Heart Rate Variability Detection, Matthew Joseph Pogorelec
Hrv - Ecg Generator: Software For Testing Heart Rate Variability Detection, Matthew Joseph Pogorelec
Theses and Dissertations
Heart rate variability (HRV) has been shown to serve as an effective diagnostic and prognostic tool in a variety of clinical applications, including for patients who have suffered from myocardial infarction, sepsis and liver cirrhosis. There currently exist a variety of devices and software to quantify HRV based on RR interval series collected from ECG data. However, as the uses for HRV expand, a greater variety of devices for different applications are being designed and developed. Thus, it is useful to have available a method for efficiently testing preliminary software. The HRV/ECG Generator software is designed to build both an …