Biomedical Engineering and Bioengineering Commons^™

Fluorescent Biosensors To Measure Endothelial Cell Responses To Fluid Shear Stress, Natalie Noll

UROP Posters

The response of endothelial cells, innermost layer of blood vessels, to blood flow is thought to be critical in the initiation and progression of atherosclerosis. Atherosclerosis in the human body is non-random and is highly correlated to vessel sites which experience oscillatory and reversing blood flow. Endothelial cells (ECs), the inner most cell layer of blood vessels are highly responsive to the drag force from blood flow, known as shear stress. To study endothelial cell responses to shear stress we used a parallel plate flow chamber in which we exposed endothelial cells to defined fluid shear stress. Using fluorescence resonance …

Hemodynamic Responses To Thermal Stimulation In The Prefrontal Cortex Of The Brain Measured By Fnirs, Koumudi Chari

Bioengineering Theses - Archive

Although FMRI has marked its importance in the neurological research by understanding the brain activities, FNIRS has also set a new standard in the brain imaging study research with non-invasive and easy to use technology. FNIRS is a portable, inexpensive optical imaging method that measures the changes in the oxygenated and de-oxygenated hemoglobin of the brain that results from the neurological activity. In this study, FNIRS has been used to study the pain processing in humans by measuring the pre-frontal cortex area of the brain. Eight (n=8) healthy subjects were induced with pain using a thermal stimulator device with temperatures …

An Investigation Of The Covariations Between Variations In Exhaled Carbon Dioxide And Cerebral Blood Flow Levels During Apnea, Varun Ajay Kanal

Bioengineering Theses - Archive

Sleep apnea is a breathing disorder characterized by repetitive reduction or cessation of breathing during sleep. It is estimated that that around 17% of adults suffer from mild to severe sleep disordered breathing. The aim of this study was to investigate the level of correlation between variations in exhaled CO2 and cerebral blood flow (CBF) during apnea. It is difficult to measure the CBF during sleep. This relationship was found in an effort to substitute the measurement of the changes in CBF with the changes in the CO2. The relationship between these two physiological parameters was first studied in healthy …

Thermosensitive Gel Containing Cellulose Acetate Phthalate-Efavirenz Combination Nanoparticles For Prevention Of Hiv-1 Infection, Abhijit A. Date, Annemarie Shibata, Emily Mcmullen, Krista La Bruzzo, Patrick Bruck, Michael Belshan, You Zhou, Christopher J. Destache

Nebraska Center for Biotechnology: Faculty and Staff Publications

The objective of this investigation was to develop and evaluate a nano-microbicide containing a combination of cellulose acetate phthalate (HIV-1 entry inhibitor) and efavirenz (anti-HIV agent) for HIV prophylaxis. Cellulose acetate phthalate-efavirenz combination nanoparticles (CAP-EFV-NPs) were fabricated by the nanoprecipitation method and were characterized for particle size, zeta potential and encapsulation efficiency of efavirenz. CAP-EFV-NPs were incorporated into a thermosensitive gel (CAP-EFV-NP-Gel). CAP-EFV-NPs, CAP-EFV-NP-Gel and efavirenz solution were evaluated for cytotoxicity to HeLa cells and for in vitro short-term (1-day) and long-term (3-day) prophylaxis against HIV-1 infection in TZM-bl cells. CAP-EFV-NPs had size < 100 nm, negative surface charge and encapsulation efficiency of efavirenz was > 98%. CAP-EFV-NPs and CAP-EFV-NP-Gel were significantly less …

Technoeconomics And Sustainability Of Renewable Methanol And Ammonia Productions Using Wind Power-Based Hydrogen, Michael J. Matzen, Mahdi H. Alhajji, Yaşar Demirel

Yaşar Demirel Publications

This study analyzes and compares the economics and sustainability aspects of two hydrogenation processes for producing renewable methanol and ammonia by using wind-power based electrolytic hydrogen. Carbon dioxide from an ethanol plant is used for producing methanol, while the nitrogen is supplied by an Air Separation Unit (ASU) for producing ammonia. The capacities are 99.96 mt/day methanol and 1202.55 mt/day anhydrous ammonia. The methanol plant requires 138.37 mt CO₂/day and 19.08 mt H₂/day. The ammonia is synthesized by using 217.72 mt H₂/day and 1009.15 mt N₂/day. The production costs and the carbon …

Quantifying Magnetic Moments And Susceptibilities Of Small Cylindrical And Spherical Objects In Mri, Ching-Yi Hsieh

Wayne State University Dissertations

Purpose: The purpose of this PhD work is to develop a method for accurately quantifying effective magnetic moments and susceptibility of either cylindrical or spherical-like small objects from magnetic resonance imaging (MRI). A standard 3D gradient echo sequence with only one echo time is intended for our approach to measure the effective magnetic moment of a given object of interest. For the quantification of the susceptibility in the cylindrical objects at different orientations, a standard 3D gradient echo sequence with only one or two echo times is needed.

Methods: Our method is to sum over complex MR signals around the …

Biom 4110/6110: The Science Of Medicine, Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Integration of fundamental principles from physics, chemistry, biology and mathematics, and applications of these principles to solve problems in medicine.

Biomimetic Oral Mucin From Polymer Micelle Networks, Sundar Prasanth Authimoolam

Theses and Dissertations--Chemical and Materials Engineering

Mucin networks are formed by the complexation of bottlebrush-like mucin glycoprotein with other small molecule glycoproteins. These glycoproteins create nanoscale strands that then arrange into a nanoporous mesh. These networks play an important role in ensuring surface hydration, lubricity and barrier protection. In order to understand the functional behavior in mucin networks, it is important to decouple their chemical and physical effects responsible for generating the fundamental property-function relationship. To achieve this goal, we propose to develop a synthetic biomimetic mucin using a layer-by-layer (LBL) deposition approach. In this work, a hierarchical 3-dimensional structures resembling natural mucin networks was generated …

Noncontact Diffuse Correlation Tomography Of Breast Tumor, Lian He

Theses and Dissertations--Biomedical Engineering

Since aggressive cancers are frequently hypermetabolic with angiogenic vessels, quantification of blood flow (BF) can be vital for cancer diagnosis. Our laboratory has developed a noncontact diffuse correlation tomography (ncDCT) system for 3-D imaging of BF distribution in deep tissues (up to centimeters). The ncDCT system employs two sets of optical lenses to project source and detector fibers respectively onto the tissue surface, and applies finite element framework to model light transportation in complex tissue geometries. This thesis reports our first step to adapt the ncDCT system for 3-D imaging of BF contrasts in human breast tumors. A commercial 3-D …

Layered, Flexible Drug Delivery Films For The Prevention Of Fibrotic Scar Tissue Formation, Cheryl L. Rabek

Theses and Dissertations--Biomedical Engineering

Open wounds account for about 50% of military injuries and 10% of non‐fatal traffic injuries. Scar tissue formation in these wounds may be reduced or prevented if treated with a combination of molecules whose release is tuned to the healing phases. The goal of this research was to develop flexible, layered drug delivery films for sequential, localized release of anti‐inflammatory, anti‐oxidant, and anti‐fibrotic molecules to soft tissue.

Films were composed of cellulose acetate phthalate (CAP) and Pluronic F‐127 (Pluronic). To impart flexibility, plasticizers, triethyl citrate (TEC) or tributyl citrate (TBC), were added. Mechanical analysis was performed on films as prepared …

Du06, Center For Orthopaedic Biomechanics, Michael D. Harris, Phd, Kevin Shelburne, Phd

Natural Knee Data

No abstract provided.

Experimental-Computational Analysis Of Vigilance Dynamics For Applications In Sleep And Epilepsy, Farid Yaghouby

Theses and Dissertations--Biomedical Engineering

Epilepsy is a neurological disorder characterized by recurrent seizures. Sleep problems can cooccur with epilepsy, and adversely affect seizure diagnosis and treatment. In fact, the relationship between sleep and seizures in individuals with epilepsy is a complex one. Seizures disturb sleep and sleep deprivation aggravates seizures. Antiepileptic drugs may also impair sleep quality at the cost of controlling seizures. In general, particular vigilance states may inhibit or facilitate seizure generation, and changes in vigilance state can affect the predictability of seizures. A clear understanding of sleep-seizure interactions will therefore benefit epilepsy care providers and improve quality of life in patients. …

A Local, Sustained Delivery System For Zoledronic Acid And Rankl-Inhibitory Antibody As A Potential Treatment For Metastatic Bone Disease, Rohith Jayaram

Theses and Dissertations--Biomedical Engineering

Cancerous solid tumors can migrate and lead to metastatic bone disease. Drugs prescribed to reduce bone resorption from metastasis, such as zoledronic acid and the RANKL-inhibitory antibody Denosumab, cause side effects such as osteonecrosis of the jaw when delivered systemically. This project used two biocompatible materials, acrylic bone cement (PMMA) and poly(lactic-co-glycolic acid) (PLGA), to incorporate and sustain release of anti-resorptive agents. Results showed similar mechanical properties for acrylic bone cements loaded up to 6.6% drug by weight. Results showed sustained zoledronic acid release for 8 weeks from both systems, with PMMA releasing up to 22% of loaded drug and …

Improving Practices In Nanomedicine Through Near Real-Time Pharmacokinetic Analysis, Isidro B. Magana

Doctoral Dissertations

More than a decade into the development of gold nanoparticles, with multiple clinical trials underway, ongoing pre-clinical research continues towards better understanding in vivo interactions. The goal is treatment optimization through improved best practices. In an effort to collect information for healthcare providers enabling informed decisions in a relevant time frame, instrumentation for real-time plasma concentration (multi-wavelength photoplethysmography) and protocols for rapid elemental analysis (energy dispersive X-Ray fluorescence) of biopsied tumor tissue have been developed in a murine model. An initial analysis, designed to demonstrate the robust nature and utility of the techniques, revealed that area under the bioavailability curve …

A Probabilistic Fracture Assessment Of Vertebral Cortical Bone, Tarun Goswami, Isaac Mabe

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Cortical bone is a material with a porous structure. The presence of pores creates local stress concentrations and the likelihood of premature failure. Assuming that pores are present in all bone, vertebral endplates, for example, can subside. Subsidence has taken place at rates as high as 77 percent. A computational probabilistic assessment of the pore size distribution and their contribution to the fracture toughness has been presented in this paper. A Monte Carlo simulation was used to develop and assign random pores. Also the model compared crack sizes to the thickness of the cortical bone present as a limiting case. …

Du05, Center For Orthopaedic Biomechanics, Michael D. Harris, Phd, Kevin Shelburne, Phd

Natural Knee Data

No abstract provided.

Du04, Center For Orthopaedic Biomechanics, Michael D. Harris, Phd, Kevin Shelburne, Phd

Natural Knee Data

No abstract provided.

Du03, Center For Orthopaedic Biomechanics, Michael D. Harris, Phd, Kevin Shelburne, Phd

Natural Knee Data

No abstract provided.

Du01, Center For Orthopaedic Biomechanics, Michael D. Harris, Phd, Kevin Shelburne, Phd

Natural Knee Data

No abstract provided.

In Situ Oh Generation From O2- And H2o2 Plays A Critical Role In Plasma Induced Cell Death, Dehui Xu, Dingxing Liu, Biqing Wang, Chen Chen, Zeyu Chen, Dong Li, Yanjie Yang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

Reactive oxygen and nitrogen species produced by cold atmospheric plasma (CAP) are considered to be the most important species for biomedical applications, including cancer treatment. However, it is not known which species exert the greatest biological effects, and the nature of their interactions with tumor cells remains ill-defined. These questions were addressed in the present study by exposing human mesenchymal stromal and LP-1 cells to reactive oxygen and nitrogen species produced by CAP and evaluating cell viability. Superoxide anion (O₂-) and hydrogen peroxide (H₂O₂) were the two major species present in plasma, but their …