Biological Engineering Commons^™

Micro-Physiological Models To Mimic Mucosal Barrier Complexity Of The Human Intestine In Vitro, Abhinav Sharma

Doctoral Dissertations

The mucosal barrier in the intestine is vital to maintain selective absorption of nutrients while protecting internal tissues and maintaining symbiotic relationship with luminal microbiota. This bio-barrier consists of a cellular epithelial barrier and an acellular mucus barrier. Secreted mucus regulates barrier function via in situ biochemical and biophysical interaction with luminal content that continually evolves during digestion and absorption. Increasing evidence suggests that a mucus barrier is indispensable to maintain homeostasis in the gastrointestinal tract. However, the importance of mucus barrier is largely underrated for in vitro mucosal tissue modeling. The major gap is the lack of experimental material …

Assessment Of The Use Of Low Molecular Weight Diblock Copolymers For The Formation Of Stable, Tunable Droplet Interface Bilayers, Joseph Tawfik

Masters Theses

This thesis presents the use of diblock copolymers, poly(butadiene)-b-poly(ethylene oxide) (PB_m PEO_n) and poly(isoprene)-b-poly(ethylene oxide) (PI_mPEO_n), as amphiphilic molecular building blocks for the formation of synthetic polymer bilayer membranes using the droplet interface bilayer (DIB) technique. The DIB technique makes use of the self-assembly of amphiphilic macromolecules along oil-water droplet interfaces that can then be physically connected for the construction of liquid supported macromolecular bilayers at the droplet interface. These bilayer membranes are capable of hosting both naturally occurring and synthetic protein channels. This technique has been used to form synthetic bilayer membranes …

Incorporation Of Lignin In Natural And Synthetic Biomaterials To Alter Mechanical And Biochemical Properties For Enhanced Wound Healing, Jorge Alfonso Belgodere

LSU Doctoral Dissertations

It is estimated that chronic, non-healing wounds affect more than 6.5 million Americans annually, with an estimated healthcare cost beyond $14 billion. Here, we attempted to create composites of natural (collagen type I or gelatin-methacrylate) or synthetic (poly(ethylene glycol) polymers incorporating a natural plant component, lignin, to combat the costs and limitations current wound healing methods face. Three-dimensional matrices of collagen type I (Col I) are widely used in tissue engineering applications for its abundance in many tissues, bioactivity with many cell types, and excellent biocompatibility. Inspired by the structural role of lignin in plant tissue, we found that sodium …

Bacteria Analysis By Using A Supervised Machine Learning Algorithm Based On Droplet Microfluidics, Yulder Daniel Angarita

Electronic Theses and Dissertations

Sepsis is a major medical problem and massive resources have been invested in developing and evaluating alternative treatments. Statistics indicate that sepsis causes between one third and one half of all hospital deaths in the United States. Sepsis has a high impact on health care in the US, with direct sepsis costs in 2009 exceeding $15.4 billion. A research study found that a 1-hour delay in appropriate antimicrobial care resulted in a 7% - 10% rise in mortality. Several professional societies seek to reduce sepsis mortality by targeting the timely use of diagnostic tests and antimicrobial therapy. The diagnostic instruments …

Photo-Characterization Of Selective Luminescent Protein Aggregate Sensors - Oligo-P-Phenylene Ethynylene (Opes), Florencia A. Monge

Biomedical Engineering ETDs

Neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease,

and related tauopathies, are a global health care challenge due to the lack of early

treatment and diagnostic options. These diseases take an emotional and physical

toll on patients, caretakers, and a rather large economic toll on taxpayer-based

health care systems. The pathologies of these diseases are characterized by the

aggregation of misfolded proteins, amyloid-β (Aβ) and tau, into β-sheet rich

structures called amyloids. Research has found that the presence of protein

aggregates predates cognitive symptoms by years. Current diagnostic tools are

based on the detection of these amyloid aggregates, historically by …

Bio Circuits For Evolutionary Biotech, Camilo Toruno

ENGS 86 Independent Projects (AB Students)

The field of bioengineering has much promise for renewable chemical production, bioremediation, and of course medical applications. Developing new useful microorganisms is extremely time and capital intensive, typically taking 50 million USD and eight years. This is due in large part to the low throughput techniques that are characteristic of the field of metabolic engineering. Here we describe the modification of an existing synthetic biosensor to measure the pharmaceutical dopamine, and the use of a circuit simulator Cadence to predict improvements to the biosensor. This biosensor paired with directed evolution techniques could reach throughputs of 5 million cells per day …

Pilot Study Exploring The Effect Of Targeted Cox-2 Inhibition In Macrophages Responding To Neuronal Injury; Promoting Enhanced Axonal Regeneration, Alyssa Brauckmann

Electronic Theses and Dissertations

Celecoxib nanoemulsion (CXB-NE) has been developed as a macrophage targeted analgesics by Dr. Janjic and her team at Duquesne University, (Janjic et al, 2018; Liu et al, 2020; Saleem et al, 2019b; Vasudeva et al, 2014). The CXB-NE nanoemulsion carrying a Nonsteroidal Anti-inflammatory (NSAID) inhibitor of COX-2 activity result in a reduction in PGE2 expression in macrophages. Using CXB-NE in rats that have peripheral nerve injury constricting the sciatic nerve relieves hypersensitivity, a pain-like behavior. The treatment also decreases inflammation associated with this chronic constriction injury (Janjic et al, 2018; Saleem et al, 2019b; Stevens et al, 2019). In this …

Design Of A 3d Printed Bioreactor For Bone Cancer Research, Brooklyn K. Vanderwolde, Katelyn Hillson

The Journal of Undergraduate Research

Bone cancer is an aggressive disease and has peak occurrence during physiological stimulation of growth and aging. Astronauts who undergo long-term space missions also acquire an increased risk of bone tissue degeneration and cancer. Few in-vitro models currently exist capable of reproducing the complex microenvironment of bone tissue to support multicellular activity in a three-dimensional structure. This limits the ability to understand disease progression and develop suitable treatment strategies. Therefore, developing a bone tissue model and an associated bioreactor is critical to understand the risks associated with cancer progression and improve treatment and preventions related to those risks. The goal …

Cell Line-Specific Differences In Guided Differentiation Of Adipose-Derived Mesenchymal Stem Cells Towards Smooth Muscle Cells, Sherly Makar

Biomedical Engineering Undergraduate Honors Theses

Mesenchymal stem cells (MSCs) are a population of stromal cells found traditionally in the bone marrow and adipose tissues. They can also be found in other tissues including fallopian tube, core blood, peripheral blood, fetal liver, and lungs. Mesenchymal stem cells have profound effects in regenerative engineering, tissue repair and drug discovery owing to the excellent properties such as proliferation, self-renewal, and multipotency generating multiple cell types including adipocytes, osteocytes, cardiomyocytes (CMs), pericytes (PCs), and chondrocytes. MSCs are used as immunomodulators in generating progenitor cells to be used for transplantation, creating engineered organs, and preventing graft vs. host disease (GVHD). …

Transcriptomic Analysis Of Cytokine-Treated Tissue-Engineered Cartilage As An In Vitro Model Of Osteoarthritis, Jiehan Li

McKelvey School of Engineering Theses & Dissertations

Osteoarthritis (OA), as the most common form of arthritis and a leading cause of disability worldwide, currently has no disease-modifying drugs. Inflammation plays an important role in cartilage degeneration in OA, and pro-inflammatory cytokines, IL-1β and TNF-α, have been shown to induce degradative changes along with aberrant gene expression in chondrocytes, the only resident cells in cartilage. The goal of this study was to further understand the transcriptomic regulation of tissue-engineered cartilage in response to inflammatory cytokines using an in vitro miPSC model system. We performed RNA sequencing for the IL-1β or TNF-α treated tissue-engineered cartilage derived from murine iPSCs, …

From Soap Bubbles To Cell Membranes, Peter Beltramo

Science and Engineering Saturday Seminars

Have you ever blown a soap bubble and wondered - what causes the bubble to be so stable and produces those colorful reflections of light? The answer lies in a class of molecules known as surfactants, and they have remarkable similarities with the molecules that comprise the cell membrane of all living organisms. In this workshop, we will use the analogy of a soap bubble to describe cellular membrane properties such as chemistry, structure, membrane transport, and ion channel formation. The goals of this workshop are to 1) link initially intractable concepts in biology like intracellular transport to the intuitive …

Nanofiber Scaffolds As 3d Culture Platforms, Stephanie Bule

Dissertations, Master's Theses and Master's Reports

Cell culture has become the basis for understanding the fundamental mechanisms of cell, tissue and organ function. Although major advancements in uncovering the underlying processes and mechanisms of normal and diseased cell biology have been made by using two-dimensional (2D) cell culture, there is a recent shift in moving towards three-dimensional (3D) culture platforms. The motivation is to better recapitulate the microenvironment of cells in vivo to obtain results that are more indicative to actual cellular processes. In this study, electrospun nano-fibrous scaffolds made of polycaprolactone were used as a 3D culture tool to investigate difference in cell behavior and …

Higher Tensile Forces Across Cellular Junctions And An Intact Nuclear Linc Complex Is Required For Epithelial Function And Stability, Fnu Vani Narayanan

Theses and Dissertations

Recent advances in three-dimensional (3D) cell culture systems have provided key insights into the understanding of biochemical and physiological states of native tissue. A significant progress in the field of mechanobiology involves measuring cellular traction forces in a more native 3D environment. However, the effects of mechanical forces exerted across cellular junctions and the nuclear LINC complex, in an organized 3D system has not been investigated thus far. Epithelial cells spontaneously form acini (also known as cysts or spheroids) with a single, fluid-filled central lumen, when grown in 3D matrices. The size of the lumen is dependent on apical secretion …

The Impact Of Aging And Mechanical Injury On Alveolar Epithelial And Macrophage Responses In Acute Lung Injury And Inflammation, Michael S. Valentine

Theses and Dissertations

Patients with severe lung pathologies, such as Acute Respiratory Distress Syndrome (ARDS), often require mechanical ventilation as a clinical intervention; however, this procedure frequently exacerbates the original pulmonary issue and produces an exaggerated inflammatory response that potentially leads to sepsis, multisystem organ failure, and mortality. This acute lung injury (ALI) condition has been termed Ventilator-Induced Lung Injury (VILI). Alveolar overdistension, cyclic atelectasis, and biotrauma are the primary injury mechanisms in VILI that lead to the loss of alveolar barrier integrity and pulmonary inflammation. Stress and strains during mechanical ventilation are believed to initiate alveolar epithelial mechanotransduction signaling mechanisms that contribute …