Bioimaging and Biomedical Optics Commons^™

Optical Spectrsocopy Of Murine Breast Tumor To Distinguish Indolent From Aggressive Disease, Joel Rodriguez Troncoso

Biomedical Engineering Undergraduate Honors Theses

Breast cancer accounts for 30% of all cancer. Metastasis is the primary cause of death among breast cancer patients. Additionally, current molecular profiling methods such as Oncotype DX, which are expensive and not widely available at all clinical facilities, only determine the risk of recurrence after treatment. Therefore, there are no current method capable of identifying metastatic patients in advance.As a result, there is an unmet clinical need to develop a cost-effective prognostic to differentiate between indolent and aggressive breast tumors. In this study, we implemented diffuse reflectance spectroscopy (DRS) system to evaluate functional changes in tumor xenografts originated from …

Quantitative Analysis Techniques For Assessing Organelle Organization And Dynamics In Individual Cells, Isaac Vargas

Graduate Theses and Dissertations

In biomedical optics and microscopy, the organization and morphology of organelles have been widely studied. In spite of novel imaging techniques, there is still a lack of quantitative tools to easily measure cellular characteristics from image data. Previous studies have explored multiple approaches to assess organelle organization and alignment, resulting in complicated and extensive algorithms that are both subject to multiple steps of image processing and influenced by non-cellular artifacts. In this thesis, a technique called the Modified Blanket Method (MBM) is introduced to quantify organelle organization through measurements of fractal dimension (FD) on a pixel-by-pixel basis. With the use …

In Vivo Metabolic And Vascular Response To Hypoxia In Twist Knockdown Murine Breast Cancer, Brandon Sturgill

Graduate Theses and Dissertations

Twist transcription factor is often overexpressed in aggressive tumors. Although needed in early embryonic development for organogenesis, Twist is known to induce an epithelial to mesenchymal transition in cells. In cancer, epithelial to mesenchymal transitions can lead to increased motility and invasiveness. It has also been linked to metabolic reprogramming and increased metastatic risk. Furthermore, metabolic preferences can increase proliferation, enhance metastatic potential, and influence the site of metastasis. We hypothesize that Twist directly affects the metabolism of cancer cells. We expect to see in vivo what we have seen in vitro; Twist overexpression should promote a shift away from …

Investigation Of The Effect Of Age On Regenerative Outcomes Following Treatment Of Volumetric Muscle Loss Injuries, John Taehwan Kim

Graduate Theses and Dissertations

Volumetric muscle loss (VML) is a traumatic injury in skeletal muscle resulting in the bulk loss of more than 20% of the muscle’s volume. Included in the bulk loss of muscle is the skeletal muscle niche comprised of nerve bundles, vasculature, local progenitor cells, basal lamina, and muscle fibers, overwhelming innate repair mechanisms. The hallmark of VML injury is the excessive accumulation of non-contractile, fibrotic tissue and permanent functional deficits. Though predominant in the younger demographic, the elderly population is also captured within VML injuries. There are many factors that change with aging in skeletal muscle that may further hinder …

Automatic Methods To Enhance The Quality Of Colonoscopy Video, Nidhal Kareem Shukur Azawi

Graduate Theses and Dissertations

Colonoscopy is a form of endoscopy because it uses colonoscopy device to help the doctor to understand a colon patient. Enhancing the quality of Colonoscopy images is a challenge because of the wet and dynamic environment inside the colon causes many problems even the colonoscope devise has a good quality. Some of these problems are blurriness, specular highlights shiny areas.

In this work, different kinds of techniques have been investigated in order to improve the quality of colonoscopy images. Also, variety of preprocessing approaches (removing bad images, resizing images, median filtration with and without image resizing) have been conducted to …

Visualizing Ischemic Skin Flap Necrosis Through Phasor Analysis Of Autofluorescence Lifetime Images, Hallie Ramser Toomer

Graduate Theses and Dissertations

Necrotic skin flaps are difficult to predict and treat due to the lack of quantitative biomarkers. Label-free multiphoton microscopy is well suited for non-invasively monitoring skin metabolism through NAD(P)H and other intrinsic fluorophores, and offers immediate future directions for assessing necrosis in the clinic. The objective of this study was to assess whether phasor FLIM could be used to evaluate skin flap status and treatment efficacy in ex vivo skin sections. Phasor maps revealed differences in growth factor treatment and region, but changes in skin flap autofluorescence at 755nm excitation and 460nm emission were not just related to NAD(P)H. A …

Investigation Of Acute Radiation-Induced Changes In Oxygenation In A Murine Breast Tumor Model, Alaa Abdelgawad

Biomedical Engineering Undergraduate Honors Theses

Around 50-60% of all cancer patients undergo radiation therapy. Although some patients show complete response with no recurrence, a significant proportion of the population still develop radiation resistance. It is important to identify tumor resistance at early stages of therapy in order to adjust treatment protocol and avoid extra exposure to radiation. Current methods to assess treatment response are only limited to anatomical measurements of tumor volume after therapy. Novel approaches that shed the light on any functional information during the course of radiotherapy could significantly improve our ability to identify patients who do not respond to radiation therapy. Diffuse …

Modeling And Validation Of Tissue Optical Properties In The Photon Transport Regime, Katelyn Heath

Biomedical Engineering Undergraduate Honors Theses

Early detection of changes in epithelial cells, such as the development of neoplastic formations seen in epithelial dysplasia, can indicate regions of the epithelial tissue that are at a high risk for cancerous formation. Using concepts from diffuse reflectance spectroscopy, a Monte Carlo model was developed to predict the reflectance measured by a detector at a small source-detector separation on a microendoscope. The Monte Carlo results were then used to calculate a mathematical relationship between the reflectance and distance that can be used to determine optical properties in a tissue sample. This model was validated with liquid phantoms of specified …

Vector Flow Imaging In Pediatric Cardiology - Extracting And Validating Data, Mason Belue

Biomedical Engineering Undergraduate Honors Theses

In the field of bedside cardiac diagnostic imaging, Doppler Ultrasound (DU) is the gold standard for diagnosing heart conditions. The largest benefit of DU is its ability to noninvasively image cardiac flow and allow the estimation of blood velocity and quantification of anatomical disease. However, to get correct velocity estimation, the position of the transducer in relation to the flow field needs to be known. This is the problem of angle/direction dependency and limits DUs accuracy when imaging in areas where perfect alignment or exact position of the transducer in relation to flow field is not possible or known, such …

Autofluorescence To Study The Effects Of Acid Concentration On Cellular Metabolism In Vitro, Robin L. Raley

Chemistry & Biochemistry Undergraduate Honors Theses

Ultraviolet (UV) radiation-induced sunburns and their accompanying afflictions are a growing public health concern in the United States. There is a need for techniques that can accurately and non-invasively characterize the physiology of sunburned skin tissue directly after UV-damage and applying a topical skin treatment to relieve pain and promote healing. Two-photon excited fluorescence (TPEF) microscopy and fluorescence lifetime imaging (FLIM) can be used to investigate metabolic processes in live cells through endogenous fluorescence of the cofactors, NADH and FAD. These methods employ the optical redox ratio of FAD/(NADH+FAD), mean NADH lifetime, and the separation of the free and bound …

Diffuse Reflectance Spectroscopy To Quantify In Vivo Tissue Optical Properties: Applications In Human Epithelium And Subcutaneous Murine Colon Cancer, Gage Joseph Greening

Graduate Theses and Dissertations

Colorectal cancer is the 4th most common and 2nd deadliest cancer. Problems exist with predicting which patients will respond best to certain therapy regimens. Diffuse reflectance spectroscopy has been suggested as a candidate to optically monitor a patient’s early response to therapy and has been received favorably in experimentally managing other cancers such as breast and skin. In this dissertation, two diffuse reflectance spectroscopy probes were designed: one with a combined high-resolution microendoscopy modality, and one that was optimized for acquiring data from subcutaneous murine tumors. For both probes, percent errors for estimating tissue optical properties (reduced scattering coefficient and …

Morphological Features Of Dysplastic Progression In Epithelium: Quantification Of Cytological, Microendoscopic, And Second Harmonic Generation Images, Sandra Patricia Gordon

Graduate Theses and Dissertations

Advances in imaging technology have led to a variety of available clinical and investigational systems. In this collection of studies, we tested the relevance of morphological image feature quantification on several imaging systems and epithelial tissues. Quantification carries the benefit of creating numerical baselines and thresholds of healthy and abnormal tissues, to potentially aid clinicians in determining a diagnosis, as well as providing researchers with standardized, unbiased results for future dissemination and comparison.

Morphological image features in proflavine stained oral cells were compared qualitatively to traditional Giemsa stained cells, and then we quantified the nuclear to cytoplasm ratio. We determined …

Quantification Of Tumor-Associated Macrophages Following Immunomodulation Therapy In A Murine Allograft Model Of Colorectal Carcinoma, Caroline Spainhour

Biomedical Engineering Undergraduate Honors Theses

Colorectal Carcinoma (CRC) is one of the deadliest cancers in the world, with 150,000 new cases annually in the United States. Traditional treatments include chemotherapy and invasive surgery; however, research has shown that only 25% of patients that undergo traditional treatment have a positive result. Immunotherapy is an emerging form of cancer treatment that utilizes the patients’immune system to fight cancer cells by targeting inflammation, which plays a large role in the proliferation and metastasis of cancer cells.

Tumor-associated macrophages (TAMs) are immune cells that affect the inflammatory microenvironment of tumors. TAMs are M1 in the early stages of tumors, …

Experimental And Model-Based Terahertz Imaging And Spectroscopy For Mice, Human, And Phantom Breast Cancer Tissues, Tyler Bowman

Graduate Theses and Dissertations

The goal of this work is to investigate terahertz technology for assessing the surgical margins of breast tumors through electromagnetic modeling and terahertz experiments. The measurements were conducted using a pulsed terahertz system that provides time and frequency domain signals. Three types of breast tissues were investigated in this work. The first was formalin-fixed, paraffin-embedded tissues from human infiltrating ductal and lobular carcinomas. The second was human tumors excised within 24-hours of lumpectomy or mastectomy surgeries. The third was xenograft and transgenic mice breast cancer tumors grown in a controlled laboratory environment to achieve more data for statistical analysis.

Experimental …

Comparison Of Varying Tissue Freezing Methods On Murine Colonic Tissue, James Hughes

Biomedical Engineering Undergraduate Honors Theses

Histology often requires a tissue specimen to be embedded so that it may be sectioned, stained, and mounted on a microscope slide for viewing. One common method of tissue embedding for rapid histology is freezing, since freezing allows tissue to be stored without the need for fixing. Frozen tissue is often embedded in a medium such as Optimal Cutting Temperature (OCT) compound so that it can be sectioned using a cryostat. However, factors such as ice-crystal formation during the freezing process can cause damage to the tissue. As such, the protocol used to freeze the tissue can affect the quality …

Extraction And Analysis Of Vector Flow Imaging Data In A Pediatric Population, Bailey Stinnett

Biomedical Engineering Undergraduate Honors Theses

Vector flow imaging (VFI) is a new ultrasound technology that provides real time, angle-independent visualization of flow velocities in the heart and great vessels. Thus far, VFI has been used for superficial applications due to the limited penetration depth of available transducer probes; however, this depth in smaller pediatric patients enables adequate aortic views. In this project, VFI was used to study pediatric aortic stenosis (PAS)—a congenital heart defect that results in the narrowing of the aorta and/or aortic valve. The decision to refer PAS patients for surgical or catheter-based intervention is initially based on Doppler ultrasound. VFI is potentially …

Optical Imaging Of Metabolic Adaptability As A Biomarker For Metastatic Potential In Breast Cancer Cells, Mason G. Harper

Biomedical Engineering Undergraduate Honors Theses

Breast cancer metastasis is the main cause for mortality in breast cancer patients. However, knowledge of metastatic recurrence is limited, and there is a need to understand metastatic recurrence in order to treat breast cancer patients more effectively. Highly invasive metastatic breast cancer has shown to exhibit metabolic adaptability, transitioning from glycolysis to oxidative phosphorylation in the presence of microenvironmental stress. NADH and FAD are naturally occurring cofactor products during glycolysis and oxidative phosphorylation, respectively, and they are of particular importance during these metabolic processes due to their endogenous fluorescence. Measuring the ratio of fluorescence intensities of these cofactors through …

Detection Of Leukocytes Stained With Acridine Orange Using Unique Spectral Features Acquired From An Image-Based Spectrometer, Courtney J. Hunter

Biomedical Engineering Undergraduate Honors Theses

A leukocyte differential count can be used to diagnosis a myriad blood disorders, such as infections, allergies, and efficacy of disease treatments. In recent years, attention has been focused on developing point-of-care (POC) systems to provide this test in global health settings. Acridine orange (AO) is an amphipathic, vital dye that intercalates leukocyte nucleic acids and acidic vesicles. It has been utilized by POC systems to identify the three main leukocyte subtypes: granulocytes, monocytes, and lymphocytes. Subtypes of leukocytes can be characterized using a fluorescence microscope, where the AO has a 450 nm excitation wavelength and has two peak emission …

Characterization Of The Response Of Trpv4 To Chemical Stimulation, Jacob V. Schluns

Biomedical Engineering Undergraduate Honors Theses

Traumatic Brain Injury (TBI) is a source of acute and chronic health issues for many patients. One of the components of the brain’s response to injury is astrogliosis, in which astrocytes that normally function to repair the brain instead form scar tissue that halts repair processes. Transient Receptor Potential Vanilloid Type 4 (TRPV4) is a trans-membrane calcium channel involved in astrogliosis. Through Fura-2AM based calcium imaging, the base activity of this channel in mouse astrocyte cells was recorded. The cells were then subjected to TRPV4 agonist and antagonist stimulation and their subsequent activity levels were recorded. The data showed that …

Optimizing A Standard Fasting Time For 2-Nbdg Uptake Studies In Murine Breast Cancers, Andrew C. Briley

Biomedical Engineering Undergraduate Honors Theses

Recently, there has been a larger use of 2-NBDG, a fluorescent glucose analog, to study glucose uptake in different cell types. These cell types have ranged anywhere from bacteria to human cancer cells. However, there has yet to be a standard procedure and practice for using 2-NBDG. In this study, our goal is to create a standard fasting time for the cells before introducing 2-NBDG to them. This study uses 4T07 cells, a murine breast cancer cell line, to help optimize this fasting time. These cells were fasted at different time points in order to find the ideal fasting time. …

In Vivo Multi-Parametric Imaging Of Metastatic And Non-Metastatic Breast Cancer, Raisa B. Rasul

Biomedical Engineering Undergraduate Honors Theses

A current issue in cancer therapy is the characterization of metastatic tumors, which can increase ease of treatment and patient trials. We present an in vivo study of metastatic (4T1) and non-metastatic (4T1-TWIST KO) breast tumor sister cell lines to understand their metabolic behavior, determine differences in two modes of imaging (reflection & transmission), and observe effect of breathing higher oxygen percentage on vascular hemoglobin oxygen saturation. After injection of 10,000 cells into mice dorsal window chambers, the glucose intake and hemoglobin oxygen saturation was measured using a fluorescent glucose analog (2-NBDG) and hyperspectral trans-illumination imaging from 520-620 nm at …

Metabolic Response To Stress Differentiates Heterogeneous Cancer Cells With Varying Metastatic Potential, Kinan Alhallak

Biomedical Engineering Undergraduate Honors Theses

Intratumoral heterogeneity is ubiquitously present within primary tumors and contributes to intractable behaviors such as metastasis and mutability spatiotemporally. Mounting evidence has shown that heterogeneous cell populations can adversely affect cell metabolism and metastatic potential. The cell’s only fluorescent molecules within the electron transport chain, flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide (NADH), can allow the quantitation of cell metabolism. We demonstrate the use of the optical redox ratio (FAD/(NADH+FAD)) to determine the metabolic behaviors of a heterogeneous panel of cells with varying metastatic programs at normal conditions and following acute hypoxia. At normal conditions, we reveal an attenuation …

Development Of Breast Tissue Phantoms For Enhanced Terahertz Imaging Utilizing Microdiamond And Nano-Onion Particles, Alec Walter

Electrical Engineering Undergraduate Honors Theses

This thesis presents the work performed to develop tissue phantoms and a contrast agent that will be used in future research of terahertz time-domain imaging of breast tumor margins. Since an excised breast tumor can contain healthy fibrous and fatty tissues along with invasive ductal carcinoma (IDC), three phantom materials were developed. Solid phantom materials were made by using TX151 to solidify water in order to tune the refractive index and absorption coefficient of the fibrous tissue phantom and IDC phantom to the properties of freshly excised breast tissue. Various amounts of olive oil were added to the water prior …

Determining The Effect Of Delivery Rate On Glucose Uptake By Cancer Cells, Luke Felton

Biomedical Engineering Undergraduate Honors Theses

Radiation therapy is one of the most commonly performed cancer treatment therapies today. Radiation therapy can cause can changes to tumor vasculature and affect blood flow rates. It is important to determine how changes in blood flow rates affect tumor glycolytic uptake to better understand tumor response to radiation therapy (1). The goal of this study was to use a fluorescent analog of glucose, 2-NBDG, to study the effect of varying flow rates on glucose uptake. A microfluidic device was constructed to flow 2-NBDG through. A murine metastatic breast cancer cell line was then cultured inside this microfluidic channel, and …

Atomic Force Microscopy Based Dna Analysis, Drew Creighton

Mechanical Engineering Undergraduate Honors Theses

This report explores dry and wet scanning of a surface and DNA pickup using an AFM, as well as fluorescent staining of DNA. Dry and wet scans of DNA were obtained using a cantilever AFM tip in tapping mode. Dry scans were found to be clearer than wet scans; however, the drying process was found to decrease the thickness of DNA 2–4 times less than its original thickness. Alternately, wet scans were found to be less clear than dry scans and introduced more noise into the images obtained. Additionally, DNA kept its initial thickness during wet scanning. DNA was capable …

Optimized Protocol For Measuring 2-Nbdg Uptake As A Cellular Marker Of Glycolytic Demand, Drew Folgmann

Biomedical Engineering Undergraduate Honors Theses

2[N-(7-nitrobenz-2-oxa-1,2-diaxol-4-yl)amino]-2-deoxyglucose (2-NBDG) a fluorescently tagged analog of FDG is ideal for in vitro studies and imaging. 2-NBDG has been proven to be an adequate marker for glucose uptake in many different types of cells [1]. However, across the spectrum of 2-NBDG use a lack of consensus is observed for the following questions. What is the ideal time to fast cells to optimize cellular uptake of 2-NBDG? Also, what is the ideal concentration of 2-NBDG to be used when quantifying glucose uptake? Finally, what is the effect of serum on the uptake of 2-NBDG? To answer these questions and understand glucose …

Design Of A 3d-Printed Device For Diffuse Reflectance Spectroscopy Calibration As A Step Towards Clinical Translation, Nontapoth Vongkittiargorn

Biomedical Engineering Undergraduate Honors Theses

The diffusive reflectance and spectroscopic microendoscopy (DRSME) is a multimodal imaging system that harnesses its usefulness from different light sources. One of the modalities, diffuse reflectance spectroscopy (DRS), has been used in our lab to investigate optical properties of epithelial tissues using a broadband white light as the main source. Calibration of DRS is required as it can obtain the maximum intensity and convert it to absolute reflectance. Current manual-adjusted calibration can be lengthy and often lead to inconsistent results. Therefore, a new method of calibration is introduced where additive manufacturing (or 3D printing) technology is fully utilized.

The instrumentation …

Multiphoton Imaging Of Labeled Breast Cancer Cells To Quantify Intra And Extracellular Receptors, Sydney C. Wiggins

Biomedical Engineering Undergraduate Honors Theses

Every year 200,000 women in the United States are diagnosed with breast cancer. Of the cases diagnosed, 10% -15% are classified as triple negative breast cancer (TNBC) due to the absence of estrogen, progesterone, and HER-2/Neu receptors. This breast cancer sub-type is markedly more aggressive and twice as likely to develop in premenopausal women. TNBC is resistant to endocrine therapies and current targeted agents, making clinical need for the development of validated therapeutics for TNBC a pressing matter. To initiate drug development, the internalization of directly immunolabeled epidermal growth factor receptors (EGFR) in SK-BR-3 human breast adenocarcinoma cells was quantitated …

Intravital Microscopy Of Tumor Oxygenation And Glycolytic Demand, Jesse D. Ivers

Biomedical Engineering Undergraduate Honors Theses

There is growing concern about the over treatment of cancer because treatments are based primarily on tumor anatomy. In this study, we aim to begin the process of addressing that issue by developing an intravital technique for optically analyzing tumor biology. Two traits were identified as having significant importance in the aggression of a tumor, vascular oxygenation (SO2) and glycolytic demand. Dorsal skin flap window chambers were implanted and 4T1 and 67NR cancer cells were injected to provide a tumor model for the development of this intravital quantification technique. This study provides a detailed protocol from instrumentation setup to surgical …

Experimental Terahertz Imaging And Spectroscopy Of Ex-Vivo Breast Cancer Tissue, Tyler C. Bowman

Graduate Theses and Dissertations

This thesis presents experimental results of terahertz imaging and spectroscopy techniques to analyze excised breast cancer tissue. The pulsed terahertz system at the University of Arkansas was used to assess formalin-fixed, paraffin-embedded breast cancer tissue obtained from 22, 40, and 46 year old patients. The tissue for this research was sliced to relatively thin sections of 10 μm thick and mounted on glass slides. Terahertz reflection time and frequency domain images of the breast cancer tissue were then obtained and compared to histopathology slides from the same patient. Results showed good correlation between the reflection images and histopathology slides for …