Matching Items (10)
Description
Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative brain disease that results from repetitive brain trauma causing brain structure, personality, behavioral, and cognitive changes. CTE is currently undiagnosable and untreatable in living patients. This thesis investigates research surrounding CTE and presents a comparative discussion of the advantages and disadvantages of current

Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative brain disease that results from repetitive brain trauma causing brain structure, personality, behavioral, and cognitive changes. CTE is currently undiagnosable and untreatable in living patients. This thesis investigates research surrounding CTE and presents a comparative discussion of the advantages and disadvantages of current diagnostic methods used for other neurodegenerative diseases that may be useful for the diagnosis of CTE.
ContributorsBlair, Sierra (Co-author) / Blair, Taylor (Co-author) / Brafman, David (Thesis director) / Stabenfeldt, Sarah (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
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Description
Several debilitating neurological disorders, such as Alzheimer's disease, stroke, and spinal cord injury, are characterized by the damage or loss of neuronal cell types in the central nervous system (CNS). Human neural progenitor cells (hNPCs) derived from human pluripotent stem cells (hPSCs) can proliferate extensively and differentiate into the various

Several debilitating neurological disorders, such as Alzheimer's disease, stroke, and spinal cord injury, are characterized by the damage or loss of neuronal cell types in the central nervous system (CNS). Human neural progenitor cells (hNPCs) derived from human pluripotent stem cells (hPSCs) can proliferate extensively and differentiate into the various neuronal subtypes and supporting cells that comprise the CNS. As such, hNPCs have tremendous potential for disease modeling, drug screening, and regenerative medicine applications. However, the use hNPCs for the study and treatment of neurological diseases requires the development of defined, robust, and scalable methods for their expansion and neuronal differentiation. To that end a rational design process was used to develop a vitronectin-derived peptide (VDP)-based substrate to support the growth and neuronal differentiation of hNPCs in conventional two-dimensional (2-D) culture and large-scale microcarrier (MC)-based suspension culture. Compared to hNPCs cultured on ECMP-based substrates, hNPCs grown on VDP-coated surfaces displayed similar morphologies, growth rates, and high expression levels of hNPC multipotency markers. Furthermore, VDP surfaces supported the directed differentiation of hNPCs to neurons at similar levels to cells differentiated on ECMP substrates. Here it has been demonstrated that VDP is a robust growth and differentiation matrix, as demonstrated by its ability to support the expansions and neuronal differentiation of hNPCs derived from three hESC (H9, HUES9, and HSF4) and one hiPSC (RiPSC) cell lines. Finally, it has been shown that VDP allows for the expansion or neuronal differentiation of hNPCs to quantities (>1010) necessary for drug screening or regenerative medicine purposes. In the future, the use of VDP as a defined culture substrate will significantly advance the clinical application of hNPCs and their derivatives as it will enable the large-scale expansion and neuronal differentiation of hNPCs in quantities necessary for disease modeling, drug screening, and regenerative medicine applications.
ContributorsVarun, Divya (Author) / Brafman, David (Thesis advisor) / Nikkhah, Mehdi (Committee member) / Stabenfeldt, Sarah (Committee member) / Arizona State University (Publisher)
Created2016
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Description

Alzheimer’s disease is a disease that can affect cognition, perception and behavior and is currently untreatable. It was discovered in the early 20th century and while significant scientific advancements have occurred, there is ambiguity that remains to be researched and understood. Latinos are the largest ethnic minority in the United

Alzheimer’s disease is a disease that can affect cognition, perception and behavior and is currently untreatable. It was discovered in the early 20th century and while significant scientific advancements have occurred, there is ambiguity that remains to be researched and understood. Latinos are the largest ethnic minority in the United States and while data still needs to be uncovered, possible risk factors for developing Alzheimer’s include heart issues, poverty and obesity, age and education level, to name a few. Poverty is linked to obesity, diabetes and a low education level, which in turn have been found to have an impact on Alzheimer’s and all factors impact cardiovascular and vascular health. Due to the collectivistic culture that is deeply rooted in Latinos, there is a strong sense of family that is upheld when caring for relatives who are afflicted and may be hesitant to receive the care that is needed. Other barriers include financial stability, linguistic and cultural barriers, underutilizing resources and health literacy. There are still research gaps that are yet to be filled like brain health and longitudinal studies for Latinos, but current treatments like diet and culturally competent professionals can help with the prognosis. Alzheimer’s is a complex disease, but with the numerous efforts made thus far, such as creating the LatinosAgainstAlzheimer’s Network, it will soon be able to be understood and hopefully eradicated.

ContributorsJimenez, Brittney (Author) / Wilson, Melissa (Thesis director) / Susan, Holechek (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description

The ever-increasing importance of cancer and neurodegenerative diseases continues to grow as populations across the world are affected by death and aging. The vitamin A (RXR) and vitamin D (VDR) receptor pathways offer promising potential to aid in treatment of cancer and Alzheimer’s disease. This thesis discusses the potential application

The ever-increasing importance of cancer and neurodegenerative diseases continues to grow as populations across the world are affected by death and aging. The vitamin A (RXR) and vitamin D (VDR) receptor pathways offer promising potential to aid in treatment of cancer and Alzheimer’s disease. This thesis discusses the potential application of novel analogs of Bexarotene (RXR agonist), MeTC7 (a new potent VDR antagonist), and vitamin D as possible therapeutics for cancer and Alzheimer’s disease.

ContributorsHong, Jennifer (Author) / Jurutka, Peter (Thesis director) / Wagner, Carl (Committee member) / Marshall, Pamela (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Natural Sciences (Contributor)
Created2023-05
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Description

Shoukhrat Mitalipov, Masahito Tachibana, and their team of researchers replaced the mitochondrial genes of primate embryonic stem cells via spindle transfer. Spindle replacement, also called spindle transfer, is the process of removing the genetic material found in the nucleus of one egg cell, or oocyte, and placing it in another

Shoukhrat Mitalipov, Masahito Tachibana, and their team of researchers replaced the mitochondrial genes of primate embryonic stem cells via spindle transfer. Spindle replacement, also called spindle transfer, is the process of removing the genetic material found in the nucleus of one egg cell, or oocyte, and placing it in another egg that had its nucleus removed. Mitochondria are organelles found in all cells and contain some of the cell’s genetic material. Mutations in the mitochondrial DNA can lead to neurodegenerative and muscle diseases. Mitalipov and Tachibana used spindle replacement to produce healthy offspring from an egg with mutated mitochondria in rhesus macaques (Macaca mulatta). The experiment showed that spindle transfer eliminated the chance of transmission of mitochondrial diseases from the affected primates to their offspring, offering the potential to eliminate mitochondrial diseases in humans.

Created2018-01-10
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Description

In 2009, Shoukhrat Mitalipov, Masahito Tachibana, and their team of researchers developed the technology of mitochondrial gene replacement therapy to prevent the transmission of a mitochondrial disease from mother to offspring in primates. Mitochondria contain some of the body's genetic material, called mitochondrial DNA. Occasionally, the mitochondrial DNA possesses mutations.

In 2009, Shoukhrat Mitalipov, Masahito Tachibana, and their team of researchers developed the technology of mitochondrial gene replacement therapy to prevent the transmission of a mitochondrial disease from mother to offspring in primates. Mitochondria contain some of the body's genetic material, called mitochondrial DNA. Occasionally, the mitochondrial DNA possesses mutations. Mitalipov and Tachibana, researchers at the Oregon National Primate Research Center in Beaverton, Oregon, developed a technique to remove the nucleus of the mother and place it in a donor oocyte, or immature egg cell, with healthy mitochondria. The resulting offspring contain the genetic material of three separate individuals and do not have the disease. Mitalipov and Tachibana's technology of mitochondrial gene replacement built on decades of research by different scientists and enables researchers to prevent the transmission of human mitochondrial diseases from mother to offspring.

Created2017-09-06
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Description
This dissertation explores applications of machine learning methods in service of the design of screening tests, which are ubiquitous in applications from social work, to criminology, to healthcare. In the first part, a novel Bayesian decision theory framework is presented for designing tree-based adaptive tests. On an application to youth

This dissertation explores applications of machine learning methods in service of the design of screening tests, which are ubiquitous in applications from social work, to criminology, to healthcare. In the first part, a novel Bayesian decision theory framework is presented for designing tree-based adaptive tests. On an application to youth delinquency in Honduras, the method produces a 15-item instrument that is almost as accurate as a full-length 150+ item test. The framework includes specific considerations for the context in which the test will be administered, and provides uncertainty quantification around the trade-offs of shortening lengthy tests. In the second part, classification complexity is explored via theoretical and empirical results from statistical learning theory, information theory, and empirical data complexity measures. A simulation study that explicitly controls two key aspects of classification complexity is performed to relate the theoretical and empirical approaches. Throughout, a unified language and notation that formalizes classification complexity is developed; this same notation is used in subsequent chapters to discuss classification complexity in the context of a speech-based screening test. In the final part, the relative merits of task and feature engineering when designing a speech-based cognitive screening test are explored. Through an extensive classification analysis on a clinical speech dataset from patients with normal cognition and Alzheimer’s disease, the speech elicitation task is shown to have a large impact on test accuracy; carefully performed task and feature engineering are required for best results. A new framework for objectively quantifying speech elicitation tasks is introduced, and two methods are proposed for automatically extracting insights into the aspects of the speech elicitation task that are driving classification performance. The dissertation closes with recommendations for how to evaluate the obtained insights and use them to guide future design of speech-based screening tests.
ContributorsKrantsevich, Chelsea (Author) / Hahn, P. Richard (Thesis advisor) / Berisha, Visar (Committee member) / Lopes, Hedibert (Committee member) / Renaut, Rosemary (Committee member) / Zheng, Yi (Committee member) / Arizona State University (Publisher)
Created2023
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Description

Receptor-interacting serine/threonine protein kinase 1 (RIPK1) is an enzyme whose interaction with tumor necrosis factor receptor 1 (TNFR1) has been found to regulate cell death pathways, such as apoptosis and necroptosis, and neuroinflammation. Accumulating evidence in the past two decades has pointed to increased RIPK1 activity in various degenerative disorders,

Receptor-interacting serine/threonine protein kinase 1 (RIPK1) is an enzyme whose interaction with tumor necrosis factor receptor 1 (TNFR1) has been found to regulate cell death pathways, such as apoptosis and necroptosis, and neuroinflammation. Accumulating evidence in the past two decades has pointed to increased RIPK1 activity in various degenerative disorders, including Amyotrophic Lateral Sclerosis (ALS), stroke, traumatic brain injury (TBI) and Alzheimer’s Disease (AD). Given the work showing elevated RIPK1 in neurodegenerative disorders, to further understand the role of RIPK1 in disease pathogenesis, we created a conditional mouse overexpressing neuronal RIPK1 on a C57BL/6 background. These conditional transgenic mice overexpress murine RIPK1 under the CAMK2a neuronal promoter and the transgene is under the control of doxycycline. The removal of doxycycline turns on the RIPK1 transgene. Two cohorts of transgenic mice overexpressing neuronal RIPK1 (RIPK1 OE) were produced, and both had doxycycline removed at post-natal day 21. One cohort was behaviorally tested at 3-months-of-age and the second cohort was tested at 9-months-of-age. Behavioral testing included use of the RotaRod and the Morris water maze to assess motor coordination and spatial cognition, respectively. We found that the RIPK1 OE mice showed no deficits in motor coordination at either age but displayed spatial reference learning and memory deficits at 3- and 9-months-of-age. A subset of mice from two independent cohorts were utilized to assess RIPK1 levels and neuronal number. In these two cohorts of mice used for postmortem analysis, we found that at 3 months of age, ~2 months after transgene activation, RIPK1 levels are not higher in the hippocampus or cortex of the RIPK1 OE mice, however at 9 months, ~8 months after transgene activation, RIPK1 levels are significantly higher in the hippocampus and cortex of RIPK1 OE mice compared to the NonTg counterparts. A subset of tissue was stained against the neuronal marker NeuN. Using unbiased stereology to quantify hippocampal CA1 pyramidal neurons, we found no neuronal loss in the 3-month-old RIPK1 OE mice, but a 34.01% reduction in NeuN+ neuron count in 9-month-old RIPK1 OE mice. Collectively our data shows that RIPK1 overexpression impairs spatial reference learning and memory and reduces neuron number in the CA1 of the hippocampus, underlining the potential of RIPK1 as a target for ameliorating CNS pathology.

ContributorsBoiangiu, Mara-Clarisa (Author) / Velazquez, Ramon (Thesis director) / Newbern, Jason (Committee member) / Barrett, The Honors College (Contributor) / School of Human Evolution & Social Change (Contributor) / Department of Psychology (Contributor)
Created2022-05
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Description
Healthy mitochondria are essential for cell survival. Described herein is the synthesis of a family of novel aminoquinone antioxidants designed to alleviate oxidative stress and prevent the impairment of cellular function. In addition, a library of bleomycin disaccharide analogues has also been synthesized to better probe the tumor targeting properties

Healthy mitochondria are essential for cell survival. Described herein is the synthesis of a family of novel aminoquinone antioxidants designed to alleviate oxidative stress and prevent the impairment of cellular function. In addition, a library of bleomycin disaccharide analogues has also been synthesized to better probe the tumor targeting properties of bleomycin. The first study involves the synthesis of a benzoquinone natural product and analogues that closely resemble the redox core of the natural product geldanamycin. The synthesized 5-amino-3-tridecyl-1,4-benzoquinone antioxidants were tested for their ability to protect Friedreich's ataxia (FRDA) lymphocytes from induced oxidative stress. Some of the analogues synthesized conferred cytoprotection in a dose-dependent manner in FRDA lymphocytes at micromolar concentrations. The biological assays suggest that the modification of the 2-hydroxyl and N-(3-carboxypropyl) groups in the natural product can improve its antioxidant activity and significantly enhance its ability to protect mitochondrial function under conditions of oxidative stress. The second project focused on the synthesis of a library of bleomycin disaccharide-dye conjugates and monitored their cellular uptake by fluorescence microscopy. The studies reveal that the position of the carbamoyl group plays an important role in modulating the cellular uptake of the disaccharide. It also led to the discovery of novel disaccharides with improved tumor selectivity.
ContributorsMathilakathu Madathil, Manikandadas (Author) / Hecht, Sidney M. (Thesis advisor) / Rose, Seth (Committee member) / Woodbury, Neal (Committee member) / Arizona State University (Publisher)
Created2013
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Description
It is hypothesized that changes in brain tissue microstructure, particularly degradation of neurites (i.e,. axons and dendrites) and synapses, are early drivers of Alzheimer's disease (AD) pathogenesis. Quantitative magnetic resonance imaging (MRI) tools like diffusion tensor imaging (DTI) have long been used to study AD pathogenesis. Using DTI metrics, structural

It is hypothesized that changes in brain tissue microstructure, particularly degradation of neurites (i.e,. axons and dendrites) and synapses, are early drivers of Alzheimer's disease (AD) pathogenesis. Quantitative magnetic resonance imaging (MRI) tools like diffusion tensor imaging (DTI) have long been used to study AD pathogenesis. Using DTI metrics, structural insights of neuro tissue can be inferred but not directly measured. DTI has proven to be an effective tool indicating fractional anisotrophy (FA) differences between groups of varying AD risk factor, but it does not explicitly quantify pathophysiologically-relevant features like neurite density and complexity. This study aims to develop and validate an advanced diffusion MRI acquisition and biophysical modeling platform that can be used to explicitly quantify changes to brain tissue microstructure, specifically neurite density and complexity. Ultimately, this platform will be used to study the pathogenic mechanisms that drive AD in the pre-clinical and clinical setting.
ContributorsYamada, Nelson Garr (Author) / Beeman, Scott (Thesis advisor) / Schaefer, Sydney (Committee member) / Su, Yi (Committee member) / Arizona State University (Publisher)
Created2023