Biomedical Engineering and Bioengineering Commons^™

Study Of Iron Ion Transit Through Three-Fold Channel Of Ferritin Cage, Shah Alam Limon

Graduate Theses/Dissertations

Ferritin is an iron-storage globular protein with an ability to uptake, mineralize and release iron ions in a controllable manner. The globular hollow shell allows storage of mineralized iron, with several channels responsible for the transit of ions into the shell and out of it. Understanding of the detailed molecular functioning of ferritin is required for rational design of biomimetic conjugate nano-biosystems containing ferritin-like constituents. In this work, ferritin was investigated both numerically by all-atom molecular dynamics (MD) simulations, and experimentally by Raman spectroscopy. Molecular dynamic simulations of a model system comprising iron ions (Fe2+) and a ferritin trimer expressing …

Multiple Path Particle Dosimetry For Prediction Of Mouse Lung Deposition Of Nanoaerosol Particles, Mohammed Ali

Technology Faculty Publications and Presentations

Nanoaerosolized particle (dia.<200 >nm) antibiotic inhalation therapy was tested to treat pneumonic tularemia in mice caused by Francisella novicida infection. Very limited experimental techniques are available to properly estimate inhaled doses and distribution of the drug inside the mouse lungs. To overcome this problem, computational simulation of particle deposition based on the Multiple Path Particle Dosimetry (MPPD) model was employed to simulate in vivo experimental conditions which included nasal breathing with whole body exposure to the antibiotic in the form of nano-aerosolized medicine. The deposition results were compared with several in vivo experimental data reported in literature; and satisfactory agreements …

Effects Of Filtration Conditions On Clearance Of Bacteriophage, Rigen Te

Graduate Theses and Dissertations

Virus Clearance is one of the major challenges in biopharmaceutical industry, especially in the manufacturing of drugs. U.S. Food and Drug Administration (FDA) recommends using several model bacteriophages as surrogates of pathogenic mammalian virus for process validation. In this work, two bacteriophages were tested against 30 kDa, 100 kDa, 300 kDa polyethersulfone (PES) membranes to investigate the effects of pore size on virus clearance. Virus particles were spiked into the protein feed solutions containing bovine serum albumin (BSA) or lysozyme at different concentrations. Besides protein concentration, the effects of feed pH on the filtration performance and virus rejection were also …

Frequency Sensitive Mechanism In Low-Intensity Ultrasound Enhanced Bioeffects, April D. Miller, Abdoulkadri Chama, Tobias M. Louw, Anuradha Subramanian, Hendrik J. Viljoen

Department of Chemical and Biomolecular Engineering: Faculty Publications

This study presents two novel theoretical models to elucidate frequency sensitive nuclear mechanisms in low-intensity ultrasound enhanced bioeffects. In contrast to the typical 1.5 MHz pulsed ultrasound regime, our group previously experimentally confirmed that ultrasound stimulation of anchored chondrocytes at resonant frequency maximized gene expression of load inducible genes which are regulatory markers for cellular response to external stimuli. However, ERK phosphorylation displayed no frequency dependency, suggesting that the biochemical mechanisms involved in enhanced gene expression is downstream of ERK phosphorylation. To elucidate such underlying mechanisms, this study presents a theoretical model of an anchored cell, representing an in vitro …

Intravenous Administration Of Iron Oxide Nanoparticles In The Chicken Model, Huong Thi Ngoc Le

Graduate Theses and Dissertations

To be used in health care, the safety and effectiveness of nanoparticles needs to be tested in a living organism. The objective of this project was to develop the chicken as a convenient animal model to examine tissue targeting of intravenously (i.v.)-injected iron oxide (IO) nanoparticles. In Experiment 1, different doses of IO-COOH were i.v. injected into chickens; blood was collected at 0, 5, 15, 30, and 60 minutes post-injection; liver, spleen, lung, and kidney were collected after the last blood collection. For Experiment 2, IO-COOH and IO-PEG were i.v. injected into chickens; blood and the organs were collected at …

Biomechanical Testing Of An Exercise For Strengthening The Proximal Femur., Alyssa Osbourne

Electronic Theses and Dissertations

Based on the principles of cutting edge bone remodeling research, a unique therapeutic exercise device was designed specifically to improve bone quality at the most critical location of the proximal femur prone to fracture: the superior-lateral femoral neck where the fracture first initiates during a fall. The exercise/device is intended to work by inducing enough strain in the bone to stimulate the body’s natural bone remodeling mechanisms to increase bone density in the proximal femur and consequently prevent a fracture from arising if a fall to the side does occur.

In order to test the proposed exercise, experiments simulating the …

Custom Software For The 3d Printing Of Patient Specific Plate Bending Templates In Pelvic Fracture Repair., Gordon B Lents

Electronic Theses and Dissertations

The purpose of this work is to reduce the operative time and blood loss incurred during open reduction and internal fixation (ORIF) of traumatic pelvic injuries through the creation of patient specific bending templates for reconstruction plates. These templates are 3D printed in a resin capable of being sterilized and taken into the operating room so that bending may be performed by the surgeon before the patient is opened or by another team member in parallel with the surgeon.

A novel software extension was created in 3D modeling software to allow a surgeon to individually position screws on a pelvic …

The Effect Of Surface Roughness Modifications And Chitosan Surface Coatings On Biofilm Formation For Prevention Of Orthopaedic Infections, Nathan Dewayne Smith

All Theses

Infections have been reported to occur in up to 91% of patients after orthopaedic procedures. Many of these infections are caused by bacterial biofilm growth on the surface of the implanted device. Surface modifications of fracture fixation implants have been taken into consideration in order to reduce infection rates and improve clinical results in orthopaedic procedures. Effective surface treatments will also reduce the need for antibiotics and prevent formation of drug-resistant bacteria. Titanium alloy sample discs (N=144) were prepared with six surface roughness treatments through polishing as well as with four different concentrations of chitosan through spin coating. In vitro …

Mushroom Inoculation On Switchgrass Feedstock During Storage: Effects Of Subsequent Pre-Processing For Intended Biofuels Production, Amandeep Singh Turay

Graduate Theses and Dissertations

The objective of this project was to examine the effect of fungal treatment and liquid hot water pretreatment of switchgrass combine in view of increasing glucose release. The fungal treatment consisted of incubating Pleurotus ostreatus in square switchgrass bales, at 50% moisture content for 25 days, 54 days, and 82 days. The digestibility of the switchgrass biomass was subsequently evaluated using Accelerase 1500 enzyme. Lignin is an important barrier to enzymatic hydrolysis, and it was stipulated that incubation with P. ostreatus would disrupt plant cell walls, resulting in enhanced saccharification. Three different concentrations of P. ostreatus were evaluated: 0%, 2%, …

Defects In Skeletal Muscle Subsarcolmmal Mitochondria In A Non-Obese Model Of Type 2 Diabetes Mellitus, Nicola Lai, China Kummitha, Charles Hoppel

Electrical & Computer Engineering Faculty Publications

Skeletal muscle resistance to insulin is related to accumulation of lipid-derived products, but it is not clear whether this accumulation is caused by skeletal muscle mitochondrial dysfunction. Diabetes and obesity are reported to have a selective effect on the function of subsarcolemmal and interfibrillar mitochondria in insulin-resistant skeletal muscle. The current study investigated the role of the subpopulations of mitochondria in the pathogenesis of insulin resistance in the absence of obesity. A non-obese spontaneous rat model of type 2 diabetes mellitus, (Goto-Kakizaki), was used to evaluate function and biochemical properties in both populations of skeletal muscle mitochondria. In subsarcolemmal mitochondria, …

Anaplasma Phagocytophilum Infection Modulates Expression Of Megakaryocyte Cell Cycle Genes Through Phosphatidylinositol-3-Kinase Signaling, Supreet Khanal, Hameeda Sultana, John D. Catravas, Jason A. Carlyon, Girish Neelakanta

Biological Sciences Faculty Publications

Anaplasma phagocytophilum, the agent of human granulocytic anaplasmosis infects neutrophils and other cells from hematopoietic origin. Using human megakaryocytic cell line, MEG-01, we show that expression of cell cycle genes in these cells are altered upon A. phagocytophilum infection. Expression of several cell cycle genes in MEG-01 cells was significantly up regulated at early and then down regulated at later stages of A. phagocytophilum infection. Lactate dehydrogenase (LDH) assays revealed reduced cellular cytotoxicity in MEG-01 cells upon A. phagocytophilum infection. The levels of both PI3KCA (p110 alpha, catalytic subunit) and PI3KR1 (p85, regulatory subunit) of Class …

Stretch Control Of Adipocyte Insulin Signaling, Tasneem Bouzid

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Obesity and related metabolic disorders have reached global epidemic proportions in recent decades. Excess and hypertrophic adipose tissue has been implicated in the development of various pathological diseases and disorders including Type-2 diabetes mellitus (Type-2 DM). In addition to serving as energy storage for the body, evidence also suggests that adipose tissue behaves as an endocrine organ capable of secreting bioactive cytokines known as adipokines, which mediate insulin signaling pathways in various tissues. Physical exercise has been demonstrated to positively affect insulin signaling activities potentially through increasing the secretion of insulin sensitizing adipokines and/or decreasing the secretion of pro-inflammatory insulin …

Optimization Of Prosthetic Hands: Utilizing Modularity To Improve Grip Force, Grasp, And Versatility, Jordan William Harris

UNLV Theses, Dissertations, Professional Papers, and Capstones

It has been demonstrated that although many varieties of upper limb prosthetics exist, commercially available prosthetics are outdated and unsatisfactory. Ineffectiveness and limitations have led to some prosthesis wearers having to own multiple devices, whereas others have given up on them entirely. Even though ample research has been conducted to design and test new hand designs, the industry appears to rest in an overall stagnated state.

It was proposed here, that one problem with prosthetic research is an excess of variables involved in testing, and therefore the improper application of the scientific method. It seems that each time a research …

Open Source Software For Automatic Detection Of Cone Photoreceptors In Adaptive Optics Ophthalmoscopy Using Convolutional Neural Networks, David Cunefare, Leyuan Fang, Robert F. Cooper, Alfredo Dubra, Joseph Carroll, Sina Farsiu

Biomedical Engineering Faculty Research and Publications

Imaging with an adaptive optics scanning light ophthalmoscope (AOSLO) enables direct visualization of the cone photoreceptor mosaic in the living human retina. Quantitative analysis of AOSLO images typically requires manual grading, which is time consuming, and subjective; thus, automated algorithms are highly desirable. Previously developed automated methods are often reliant on ad hoc rules that may not be transferable between different imaging modalities or retinal locations. In this work, we present a convolutional neural network (CNN) based method for cone detection that learns features of interest directly from training data. This cone-identifying algorithm was trained and validated on separate data …

A Brief Review Of Opt101 Sensor Application In Near-Infrared Spectroscopy Instrumentation For Intensive Care Unit Clinics, Ting Li, Fulin Zhong, Boan Pan, Zebin Li, Chong Huang, Zishan Deng

Biomedical Engineering Faculty Publications

The optoelectronic sensor OPT101 have merits in advanced optoelectronic response characteristics at wavelength range for medical near-infrared spectroscopy and small-size chip design with build-in trans-impedance amplifier. Our lab is devoted to developing a series of portable near-infrared spectroscopy (NIRS) devices embedded with OPT101 for applications in intensive care unit clinics, based on NIRS principle. Here we review the characteristics and advantages of OPT101 relative to clinical NIRS instrumentation, and the most recent achievements, including early-diagnosis and therapeutic effect evaluation of thrombus, noninvasive monitoring of patients' shock severity, and fatigue evaluation. The future prospect on OPT101 improvements in noninvasive clinical applications …

Chelator-Free Radiolabeling Of Serrs Nanoparticles For Whole-Body Pet And Intraoperative Raman Imaging, Matthew A. Wall, Travis Shaffer, Stefan Harmsen, Darjus-Felix Tschaharganeh, Chun-Hao Huang, Scott W. Lowe, Charles Michael Drain, Moritz F. Kircher

Publications and Research

A single contrast agent that offers whole-body non-invasive imaging along with the superior sensitivity and spatial resolution of surface-enhanced resonance Raman scattering (SERRS) imaging would allow both pre-operative mapping and intraoperative imaging and thus be highly desirable. We hypothesized that labeling our recently reported ultrabright SERRS nanoparticles with a suitable radiotracer would enable pre-operative identification of regions of interest with whole body imaging that can be rapidly corroborated with a Raman imaging device or handheld Raman scanner in order to provide high precision guidance during surgical procedures. Here we present a straightforward new method that produces radiolabeled SERRS nanoparticles for …

High Throughput Analysis Of The Penetration Of Iron Oxide/Polyethylene Glycol Nanoparticles Into Multicellular Breast Cancer Tumor Spheroids, Jonathan Robert Gabriel

Theses and Dissertations

The purpose of this study was to design and optimize a system for the high-throughput analysis of multicellular tumor spheroids (MCTS), and validate the system through the study of a complex biological model. The system was successfully created and optimized, allowing the histological recovery of MCTS at rates up to 90% for microarrays of 24-spheroids. Arrays of 96-spheroids were recovered at rates up to 86%. The system was used to study the penetration of 5k Da-polyethylene coated superparamagnetic iron-oxide nanoparticles (5k-PEG SPIONs) into HTB-126 breast cancer spheroids cultured to a mean diameter of 486 micrometer (± 25.2 micrometer). Results were …

Biomechanics Of Snoring And Sleep Apnea, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Working Papers

To understand the mechanisms of snoring and sleep apnea a first-principles biomechanical analysis was done for airflow through branched parallel channels, separated by a freely movable soft palate, and converging to a common channel at the base of the tongue in a “Y-shaped” configuration. Branches of the Y describe slit-like passages on the nasal and oral sides of the soft palate, when the palate is pushed by backward movement of the tongue to form a wedge between the tongue surface and the posterior pharyngeal wall. The common channel of the Y describes the oropharyngeal passage between the base of the …

Application Of Advanced Biomechanical Methods In Studying Low Back Pain – Recent Development In Estimation Of Lower Back Loads And Large-Array Surface Electromyography And Findings, Babak Bazrgari, Ting Xia

Biomedical Engineering Faculty Publications

Low back pain (LBP) is a major public health problem and the leading disabling musculoskeletal disorder globally. A number of biomechanical methods using kinematic, kinetic and/or neuromuscular approaches have been used to study LBP. In this narrative review, we report recent developments in two biomechanical methods: estimation of lower back loads and large-array surface electromyography (LA-SEMG) and the findings associated with LBP. The ability to estimate lower back loads is very important for the prevention and the management of work-related low back injuries based on the mechanical loading model as one category of LBP classification. The methods used for estimation …

Modeling De Novo Granulation Of Anaerobic Sludge, Anna Doloman, Honey Varghese, Charles D. Miller, Nicholas Flann

Computer Science Faculty and Staff Publications

Background: A unique combination of mechanical, physiochemical and biological forces influences granulation during processes of anaerobic digestion. Understanding this process requires a systems biology approach due to the need to consider not just single-cell metabolic processes, but also the multicellular organization and development of the granule.

Results: In this computational experiment, we address the role that physiochemical and biological processes play in granulation and provide a literature-validated working model of anaerobic granule de novo formation. The agent-based model developed in a cDynoMiCs simulation environment successfully demonstrated a de novo granulation in a glucose fed system, with the average specific methanogenic …