Matching Items (11)
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- All Subjects: Regenerative Medicine
- All Subjects: 3D Printing
- Creators: Pizziconi, Vincent
Description
The objective of this research is to investigate the relationship among key process design variables associated with the development of nanoscale electrospun polymeric scaffolds capable of tissue regeneration. To date, there has been no systematic approach toward understanding electrospinning process parameters responsible for the production of 3-D nanoscaffold architectures with desired levels quality assurance envisioned to satisfy emerging regenerative medicine market needs. , As such, this study encompassed a more systematic, rational design of experiment (DOE) approach toward the identification of electrospinning process conditions responsible for the production of dextran-polyacrylic acid (DEX-PAA) nanoscaffolds with desired architectures and tissue engineering properties. The latter includes scaffold fiber diameter, pore size, porosity, and degree of crosslinking that together can provide a range of scaffold nanomechanical properties that closely mimics the cell microenvironment. The results obtained from this preliminary DOE study indicate that there exist electrospinning operation conditions capable of producing Dex-PAA nanoarchitecture having potential utility for regenerative medicine applications.
ContributorsEspinoza, Roberta (Author) / Pizziconi, Vincent (Thesis advisor) / Massia, Stephen (Committee member) / Garcia, Antonio (Committee member) / Arizona State University (Publisher)
Created2013
Description
The Larynx plays a pivotal role in our ability to breathe and to speak. It is in our best interest to continue improving the status of tissue regeneration concerning the larynx so that patient voice quality of life can be less hindered in the face of laryngeal cancers and diseases. Modern technology can allow us to use CT scans for both diagnosis and treatment. This medical imaging can be converted into three-dimensional patient specific models that are actualized through 3D printing. These implants improve upon the current state of the art because they can be produced in a timely manner, are developed with materials and methods ensuring their biocompatibility, and follow architectures and geometries best suited for the patient to improve their voice quality of life. Additionally they should be able to allow patient speech in the case of partial laryngectomies where the arytenoid has been removed by acting as a permanent vocal fold This treatment process for laryngectomies aligns itself with personalized medicine by targeting its geometry based on that of the patient. Technologies and manufacturing processes utilized to produce them are accessible and could all be used within the clinical space. The life-saving implant required for the laryngectomy healing and recovery process can be ready to implant for the patient within a few days of imaging them.
ContributorsBarry, Colin Patrick (Author) / Pizziconi, Vincent (Thesis director) / Lott, David (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2015-05
Description
Many industries require workers in warehouse and stockroom environments to perform frequent lifting tasks. Over time these repeated tasks can lead to excess strain on the worker's body and reduced productivity. This project seeks to develop an exoskeletal wrist fixture to be used in conjunction with a powered exoskeleton arm to aid workers performing box lifting types of tasks. Existing products aimed at improving worker comfort and productivity typically employ either fully powered exoskeleton suits or utilize minimally powered spring arms and/or fixtures. These designs either reduce stress to the user's body through powered arms and grippers operated via handheld controls which have limited functionality, or they use a more minimal setup that reduces some load, but exposes the user's hands and wrists to injury by directing support to the forearm. The design proposed here seeks to strike a balance between size, weight, and power requirements and also proposes a novel wrist exoskeleton design which minimizes stress on the user's wrists by directly interfacing with the object to be picked up. The design of the wrist exoskeleton was approached through initially selecting degrees of freedom and a ROM (range of motion) to accommodate. Feel and functionality were improved through an iterative prototyping process which yielded two primary designs. A novel "clip-in" method was proposed to allow the user to easily attach and detach from the exoskeleton. Designs utilized a contact surface intended to be used with dry fibrillary adhesives to maximize exoskeleton grip. Two final designs, which used two pivots in opposite kinematic order, were constructed and tested to determine the best kinematic layout. The best design had two prototypes created to be worn with passive test arms that attached to the user though a specially designed belt.
ContributorsGreason, Kenneth Berend (Author) / Sugar, Thomas (Thesis director) / Holgate, Matthew (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The advent of medical imaging has enabled significant advances in pre-procedural planning, allowing cardiovascular anatomy to be visualized noninvasively before a procedure. However, absolute scale and tactile information are not conveyed in traditional pre-procedural planning based on images alone. This information deficit fails to completely prepare clinicians for complex heart repair, where surgeons must consider the varied presentations of cardiac morphology and malformations. Three-dimensional (3D) visualization and 3D printing provide a mechanism to construct patient-specific, scale models of cardiovascular anatomy that surgeons and interventionalists can examine prior to a procedure. In addition, the same patient-specific models provide a valuable resource for educating future medical professionals. Instead of looking at idealized images on a computer screen or pages from medical textbooks, medical students can review a life-like model of patient anatomy.
In cases where surgical repair is insufficient to return the heart to normal function, a patient may proceed to advanced heart failure, and a heart transplant may be required. Unfortunately, a finite number of available donor hearts are available. A mechanical circulatory support (MCS) device can be used to bridge the time between heart failure and reception of a donor heart. These MCS devices are typically constructed for the adult population. Accordingly, the size associated to the device is a limiting factor for small adults or pediatric patients who often have smaller thoracic measurements. While current eligibility criteria are based on correlative measurements, the aforementioned 3D visualization capabilities can be leveraged to accomplish patient-specific fit analysis.
The main objectives of the work presented in this dissertation were 1) to develop and evaluate an optimized process for 3D printing cardiovascular anatomy for surgical planning and medical education and 2) to develop and evaluate computational tools to assess MCS device fit in specific patients. The evaluations for objectives 1 and 2 were completed with a collection of qualitative and quantitative validations. These validations include case studies to illustrate meaningful, qualitative results as well as quantitative results from surgical outcomes. The latter results present the first quantitative supporting evidence, beyond anecdotal case studies, regarding the efficacy of 3D printing for pre-procedural planning; this data is suitable as pilot data for clinical trials. The products of this work were used to plan 200 cardiovascular procedures (including 79 cardiothoracic surgeries at Phoenix Children's Hospital), via 3D printed heart models and assess MCS device fit in 29 patients across 6 countries.
In cases where surgical repair is insufficient to return the heart to normal function, a patient may proceed to advanced heart failure, and a heart transplant may be required. Unfortunately, a finite number of available donor hearts are available. A mechanical circulatory support (MCS) device can be used to bridge the time between heart failure and reception of a donor heart. These MCS devices are typically constructed for the adult population. Accordingly, the size associated to the device is a limiting factor for small adults or pediatric patients who often have smaller thoracic measurements. While current eligibility criteria are based on correlative measurements, the aforementioned 3D visualization capabilities can be leveraged to accomplish patient-specific fit analysis.
The main objectives of the work presented in this dissertation were 1) to develop and evaluate an optimized process for 3D printing cardiovascular anatomy for surgical planning and medical education and 2) to develop and evaluate computational tools to assess MCS device fit in specific patients. The evaluations for objectives 1 and 2 were completed with a collection of qualitative and quantitative validations. These validations include case studies to illustrate meaningful, qualitative results as well as quantitative results from surgical outcomes. The latter results present the first quantitative supporting evidence, beyond anecdotal case studies, regarding the efficacy of 3D printing for pre-procedural planning; this data is suitable as pilot data for clinical trials. The products of this work were used to plan 200 cardiovascular procedures (including 79 cardiothoracic surgeries at Phoenix Children's Hospital), via 3D printed heart models and assess MCS device fit in 29 patients across 6 countries.
ContributorsRyan, Justin Robert (Author) / Frakes, David (Thesis advisor) / Collins, Daniel (Committee member) / LaBelle, Jeffrey (Committee member) / Pizziconi, Vincent (Committee member) / Pophal, Stephen (Committee member) / Arizona State University (Publisher)
Created2015
Description
A much anticipated outcome of the rapidly emerging field of personalized medicine is a significant increase in the standard of care afforded to patients. However, before the full potential of personalized medicine can be realized, key enabling technologies must be further developed. The purpose of this study was to use enabling technologies such as medical imaging, image reconstruction, and rapid prototyping to create a model of an implant for use in vocal fold repair surgery. Vocal fold repair surgery is performed for patients with great difficulty in phonation, breathing, and swallowing as a result of vocal fold damage caused by age, disease, cancer, scarring, or paralysis. This damage greatly hinders patients' social, personal, and professional lives due to difficulty in efficient communication. In this project, the image reconstruction of a subject's vocal fold in 3D is demonstrated utilizing NIH-funded advanced image processing software known as ITK-SNAP, which uniquely allows both semi-automatic and manual image segmentation. The hyoid bone, thyroid cartilage, arytenoid cartilage, and empty airway of the larynx were isolated using active contouring for use as anatomical benchmarks. Then, the vocal fold mold, including the vocal fold, a superior extension along the thyroid cartilage, and an inferior extension along the airway, was modeled with manual segmentation. The configured, isolated, and edited vocal fold model was converted into an STL file. This STL file can be imported to a 3D printer to fabricate a mold for reconstruction of a patient specific vocal fold biocompatible implant. This feasibility study serves as a basis to allow ENT surgeons at the Mayo Clinic to dramatically improve reparative surgery outcomes for patients. This work embodies the strategic importance of multidisciplinary teams working at the interface of technology and medicine to optimize patient outcomes.
ContributorsPatel, Anjana Ketan (Author) / Pizziconi, Vincent (Thesis director) / Lott, David (Committee member) / Department of Psychology (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Tissues within the body enable proper function throughout an individual’s life. After severe injury or disease, many tissues do not fully heal without surgical intervention. The current surgical procedures aimed to repair tissues are not sufficient to fully restore functionality. To address these challenges, current research is seeking new tissue engineering approaches to promote tissue regeneration and functional recovery. Of particular interest, biomaterial scaffolds are designed to induce tissue regeneration by mimicking the biophysical and biochemical aspects of native tissue. While many scaffolds have been designed with homogenous properties, many tissues are heterogenous in nature. Thus, fabricating scaffolds that mimic these complex tissue properties is critical for inducing proper healing after injury. Within this dissertation, scaffolds were designed and fabricated to mimic the heterogenous properties of the following tissues: (1) the vocal fold, which is a complex 3D structure with spatially controlled mechanical properties; and (2) musculoskeletal tissue interfaces, which are fibrous tissues with highly organized gradients in structure and chemistry. A tri-layered hydrogel scaffold was fabricated through layer-by-layer stacking to mimic the mechanical structure of the vocal fold. Furthermore, magnetically-assisted electrospinning and thiol-norbornene photochemistry was used to fabricate fibrous scaffolds that mimic the structural and chemical organization of musculoskeletal interfacial tissues. The work presented in this dissertation further advances the tissue engineering field by using innovative techniques to design scaffolds that recapitulate the natural complexity of native tissues.
ContributorsTindell, Raymond Kevin (Author) / Holloway, Julianne (Thesis advisor) / Green, Matthew (Committee member) / Pizziconi, Vincent (Committee member) / Stephanopoulos, Nicholas (Committee member) / Acharya, Abhinav (Committee member) / Arizona State University (Publisher)
Created2021
Description
Lab-grown food products of animal cell origin, now becoming popularly coined as, ‘Cellular Agriculture’ is a revolutionary breakthrough technology that has the potential to penetrate the lives of every American or citizen of the world. It is important to recognize that the impetus for developing this technology is fueled by environmental concerns with climate change, rising geopolitical instability, and population growth projections, where farm-grown food has now become a growing national security issue. Notwithstanding its potential, in addition to the necessary technological innovation and economic scalability, the market success of cellular agriculture will depend greatly on regulatory oversight by multiple government agencies without which it can cause undue harm to individuals, populations, and the environment. Thus, it is critical for those appropriate United States governing bodies to ensure that the technology being developed is both safe and of an acceptable quality for human consumption and has no adverse environmental impact. As such, animal foods, derived from farms, previously regulated almost exclusively by the United States Department of Agriculture (USDA) are now being regulated under a joint formal agreement between the US Food and Drug Administration (US FDA) and the USDA if derived from the lab, i.e., lab-grown animal foods. The main reason for joint oversight between the FDA and the USDA is that the FDA has developed the in-house expertise to oversee primary cell harvesting and cell storage, as well as, cell growth and differentiation for the development of 3D-engineered tissues intended for tissue and organ replacement for the emerging field of regenerative medicine. As such, the FDA has been given the authority to oversee the ‘front end’ of lab-grown food processes which relies on the very same processes utilized in engineered human tissues to produce food-grade engineered tissues. Oversight then transitions to the USDA-FSIS (Food Safety and Inspection Service) during the harvesting stage of the cell culture process. The USDA-FSIS then oversees the further production and labeling of these products. Included in the agreement is the understanding that both bodies are responsible for communicating necessary information to each other and collaboratively developing new regulatory actions as needed. However, there currently lacks clarity on some topics regarding certain legal, ethical, and scientific issues. Lab-grown meat products require more extensive regulation than farm-grown animal food products to ensure that they are safe and nutritious for consumption. To do this, CFSAN can create new classes of lab-grown foods, such as ‘lab-grown USDA foods,’ ‘lab-grown non-USDA foods,’ ‘lab-grown extinct foods,’ ‘lab-grown human food tissues,’ and ‘medically activated lab-grown foods.’
ContributorsBanen, Samuel (Author) / Pizziconi, Vincent (Thesis director) / Feigal, David (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor) / School of Molecular Sciences (Contributor)
Created2023-05
Description
This thesis aims to incorporate exosomes into an electrospun scaffold for tissue engineering applications. The motivation for this work is to develop an implant to regenerate tissue for patients with laryngeal defects. It was determined that it is feasible to incorporate exosomes into an electrospun scaffold. This addition of exosomes does alter the scaffold properties, by decreasing the average fiber diameter by roughly a factor of three and increasing the average modulus by roughly a factor of two. Cells were cultured on a scaffold with exosomes incorporated and were found to proliferate more than on a scaffold alone. This research lays the groundwork for further developing and optimizing an electrospun scaffold with exosomes incorporated to elicit a tissue regenerative response.
ContributorsKennedy, Maeve (Author) / Pizziconi, Vincent (Thesis director) / McPhail, Michael (Committee member) / School of International Letters and Cultures (Contributor) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Tissue engineering scaffold fabrication methods often have tradeoffs associated with them that prevent one method from fulfilling all design requirements of a desired scaffold. This undergraduate thesis seeks to combine 3D printing and electrospinning tissue engineering fabrication methods into a hybrid fabrication method that can potentially fulfill more design requirements than each method alone. The hybrid scaffolds were made by inserting electrospun scaffolds between layers of 3D printed scaffolds of increasing print temperature and effects on adhesion and mechanical properties were characterized. The fabrication method proved to be feasible and print temperature affected both adhesion and mechanical properties of the scaffolds. A positive, non-linear relationship was seen between print temperature and adhesion and resulting force. Insertion of electrospun mats led to increased damping of scaffolds. Evidence from characterization indicated factors other than print temperature were likely contributing to adhesion and mechanical properties. If studied further, this fabrication method could potentially be used to improve overall structure and regenerative potential of tissue engineering scaffolds.
ContributorsCornella, Joseph Paul (Author) / Pizziconi, Vincent (Thesis director) / McPhail, Michael J (Committee member) / School of Music (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Protein crystallization is a technique for the formation of three-dimensional protein crystals, which is widely utilized by scientists, engineers, and researchers. Protein crystallography allows for protein structures and functions to be studied. As proteins play a central role in biological systems and life itself, a deeper understanding of their structure-function properties is crucial to elucidating fundamental behaviors, such as protein folding in addition to the role that they play in emerging fields, such as, tissue engineering with application to the emerging field of regenerative medicine. However, a significant limitation toward achieving further advancements in this field is that in order to determine detailed structure of proteins from protein crystals, high-quality and larger size protein crystals are needed. Because it is difficult to produce adequate size, high-quality crystals, it remains difficult to determine the structure of many proteins. However, a new method using a microgravity environment to crystallize proteins has proven effective through various studies conducted on the International Space Station (ISS). In the presence of microgravity, free convection is essentially absent in the bulk solution where crystallization occurs, thus allowing for purely random Brownian motion to exist which favors the nucleation and growth of high-quality protein crystals. Many studies from the ISS to date have demonstrated that growing protein crystals in a microgravity environment produces larger and higher-quality crystals. This method provides new opportunities for better structure identification and analysis of proteins. Although there remains many more limitations and challenges in the field, microgravity protein crystallization holds many opportunities for the future of biotechnology and scientific development. The objective of this thesis was to study the crystallization of hen egg white lysozyme (HEWL) and determine the effects of both unit and microgravity on growth/size and quality of HEWL. Through preliminary trials using a universal ground-based reduced-gravity system, the crystallization of HEWL in a simulated microgravity environment was successfully conducted and the results reported are promising. The utility of continuous, scalable ground-based, microgravity platforms for studies on a wide range of material systems and behavior, such as, protein crystallization, has significant implications regarding its impact on many industries, including drug development as well as regenerative medicine.
ContributorsTran, Amanda Marie (Author) / Pizziconi, Vincent (Thesis director) / Alford, Terry (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12