Matching Items (257)
Filtering by
- Language: English
Description
In the decade since Yamanaka and colleagues described methods to reprogram somatic cells into a pluripotent state, human induced pluripotent stem cells (hiPSCs) have demonstrated tremendous promise in numerous disease modeling, drug discovery, and regenerative medicine applications. More recently, the development and refinement of advanced gene transduction and editing technologies have further accelerated the potential of hiPSCs. In this review, we discuss the various gene editing technologies that are being implemented with hiPSCs. Specifically, we describe the emergence of technologies including zinc-finger nuclease (ZFN), transcription activator-like effector nuclease (TALEN), and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 that can be used to edit the genome at precise locations, and discuss the strengths and weaknesses of each of these technologies. In addition, we present the current applications of these technologies in elucidating the mechanisms of human development and disease, developing novel and effective therapeutic molecules, and engineering cell-based therapies. Finally, we discuss the emerging technological advances in targeted gene editing methods.
ContributorsBrookhouser, Nicholas (Author) / Raman, Sreedevi (Author) / Potts, Chris (Author) / Brafman, David (Author) / Ira A. Fulton Schools of Engineering (Contributor)
Created2017-02-06
Description
Traumatic brain injury (TBI) may result in numerous pathologies that cannot currently be mitigated by clinical interventions. Stem cell therapies are widely researched to address TBI-related pathologies with limited success in pre-clinical models due to limitations in transplant survival rates. To address this issue, the use of tissue engineered scaffolds as a delivery mechanism has been explored to improve survival and engraftment rates. Previous work with hyaluronic acid \u2014 laminin (HA-Lm) gels found high viability and engraftment rates of mouse fetal derived neural progenitor/stem cells (NPSCs) cultured on the gel. Furthermore, NPSCs exposed to the HA-Lm gels exhibit increased expression of CXCR4, a critical surface receptor that promotes cell migration. We hypothesized that culturing hNPCs on the HA-Lm gel would increase CXCR4 expression, and thus enhance their ability to migrate into sites of tissue damage. In order to test this hypothesis, we designed gel scaffolds with mechanical properties that were optimized to match that of the natural extracellular matrix. A live/dead assay showed that hNPCs preferred the gel with this optimized formulation, compared to a stiffer gel that was used in the CXCR4 expression experiment. We found that there may be increased CXCR4 expression of hNPCs plated on the HA-Lm gel after 24 hours, indicating that HA-Lm gels may provide a valuable scaffold to support viability and migration of hNPCs to the injury site. Future studies aimed at verifying increased CXCR4 expression of hNPCs cultured on HA-Lm gels are necessary to determine if HA-Lm gels can provide a beneficial scaffold for stem cell engraftment therapy for treating TBI.
ContributorsHemphill, Kathryn Elizabeth (Author) / Stabenfeldt, Sarah (Thesis director) / Brafman, David (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
In an industrialized world that relies heavily on low cost production and packaging produced without a viable end-of-life strategy, the accumulation of non-biodegradable plastics in the environment and particularly the oceans today is an urgent problem of global proportions. Plastics pose a significant threat to marine mammals due to mistaken ingestion as well as potential release of plasticizers and other chemicals. However, the interactions and consequences of ingestion of oceanic plastics by marine mammals have not been thoroughly studied. In this literature review, information regarding plastic ingestion by marine mammals was compiled to estimate the magnitude of adverse impacts and identify major knowledge gaps. Using comprehensive Boolean search terms in Web of Science of literature published between 1960 and 2020, it was determined that there were large discrepancies in the amount of research conducted among 10 different categories of marine mammals, with cetaceans being the primary focus group of most studies (70.3). In addition, different areas of the world, such as southern Africa, were found to have a disproportionately small number of studies on plastic impacts on marine mammalian life in their surrounding marine waters. Differences were found in the amount of plastics ingested by marine animals and a hypothesis of explaining these observations was formulated, attributing potential ingestion of plastic to the debris resembling different food sources in the mammals’ diets as well as different feeding mechanisms.
ContributorsFredette-Roman, Cassidy (Author) / Polidoro, Beth (Thesis director) / Rolsky, Charles (Committee member) / Halden, Rolf (Committee member) / School of Life Sciences (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
The Tale of the Tigers is a children’s picture book in which a tiger named Guava is transported from his world of Serenia to our world. In an attempt to find someone to help him with this situation, Guava meets another tiger named Papaya. After having his prey scared away by Guava, Papaya begins to explain the different hardships and dangers that tigers face in their natural habitat. Papaya also teaches Guava about the different programs and activities that humans have been doing to help increase and restore tiger populations. At the end of the story, Guava returns to his world and spreads awareness to those that live in Serenia about how tigers are threatened in other places and what’s being done to help them. Papaya uses basic ecological concepts to explain the importance of tigers in their ecosystem. These concepts include habitat loss, trophic levels, landscape fragmentation, and poaching. The story also incorporates different conservation methods, including captive breeding and the use of camera traps.
ContributorsMooney, Lena (Author) / Jesse, Lewis (Thesis director) / Meloy, Elizabeth (Committee member) / College of Integrative Sciences and Arts (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Current culturing methods allow for human neural progenitor cells to be differentiated into neurons for use in diagnostic tools and disease modeling. An issue arises in the relatively low number of cells that can be successfully expanded and differentiated using these current methods, making the progress of research dependent on these cultures as a large number of cells are needed to conduct relevant assays. This project focuses on the expansion and differentiation of human neural progenitor cells cultured on microcarriers and within a rotating bioreactor system as a way to increase the total number of cells generated. Additionally, cryopreservation and the characteristics of these neurons post thaw is being investigated to create a way for long term storage, as well as, a method for standardizing cell lines between multiple experiments at different time points. The experiments covered in this study are aimed to compare the characteristics of differentiated human neurons, both demented and non-demented cell lines between pre-cryopreservation, freshly differentiated neurons and post-cryopreservation neurons. The assays conducted include immunofluorescence, calcium imaging, quantitative polymerase chain reaction, flow cytometry and ELISA data looking at Alzheimer’s disease traits. With the data collected within this study, the use of bioreactors, in addition to, cryopreservation of human neurons for long term storage can be better implemented into human neural progenitor cell research. Both of these aspects will increase the output of these cultures and potentially remove the bottleneck currently found within human neural disease modeling.
ContributorsHenson, Tanner Jay (Author) / Brafman, David (Thesis director) / Kodibagkar, Vikram (Committee member) / School of Life Sciences (Contributor) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Food provides nutrients and sustenance that are essential to life. Humans rely on food to fuel our thoughts and actions. However, food isn’t just a source of energy; it’s a fundamental part of culture and connection. Simply sharing a meal with someone can build teamwork and create a bond. Throughout this short memoir, I explored the ways in which food creates a connection across language and cultural barriers through reflection on specific experiences that I had in India, Uganda, and South Africa. While my experiences in each of these three countries were vastly different, there was one defining theme that brought them together: food. This memoir uses mixed media (personal reflection, research, recipes, and photos) to connect the three different international experiences. Reflection on my own family traditions and history bridges the gap between my upbringing and my interactions with people while spending time abroad. Popular recipes from each of the three countries are mixed into the personal reflection, showing how preparing food in a different geographic location can change the experience of preparation and eating. In addition to personal experience, included is a synthesis of research done on the effects of sharing a plate or a meal on negotiations tactics, how eating the same food increases trust, the ways in which food sharing is an act of social intimacy, and how it can build community. Food is an important part of family connection, a tool in many rituals such as Sunday dinners or breaking bread, a critical aspect of many religions, and is tied to the celebration of both birth and death in cultures around the globe. We all need to eat; food is the great commonality among people.
ContributorsRivard-Lentz, Haley Marie Anne (Co-author) / Rivard-Lentz, Haley (Co-author) / Fette, Donald (Thesis director) / Jacobs, Mark (Committee member) / School of Sustainability (Contributor) / School of Public Affairs (Contributor) / Watts College of Public Service & Community Solut (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Optical Communications are at a high point of interest by the space engineering community. After successful projects like the Lunar Laser Communications Demonstration (LLCD), NASA has become interested in augmenting their current Deep Space Network (DSN) with optical communication links. One such link is Deep Space Optical Communications (DSOC) which will be launching with the Psyche mission. To gain a full understanding of the advantages of this network, this thesis will go over the history and benefits of optical communications both on Earth and in space. This thesis will then go in depth on NASAs DSOC project through an algorithmic implementation of the communications channel.
ContributorsHorton, Paul Alexander (Author) / Mauskopf, Philip (Thesis director) / Sandy, Douglas (Committee member) / Martin, Thomas (Committee member) / Software Engineering (Contributor) / College of Integrative Sciences and Arts (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05