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- Creators: School of Molecular Sciences
- Creators: Harrington Bioengineering Program
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Description
Ethnic groups experience different societal and economic circumstances that contribute to their well-being. Life satisfaction and happiness are commonly used as a measure of well-being; but they are not often used to evaluate well-being in lower income countries. This study focuses on the self-reported life satisfaction and happiness of members of ethnic groups from low- and middle-income countries and its correlation with ethnic privilege, gender opportunity, and income. Using two self-reported measures of well-being—life satisfaction and happiness—among 110,391 women in 27 countries (ages 15-49) surveyed in Multiple Indicator Cluster Surveys, this study examines how country-level indicators of gender opportunity, ethnic-level indicators of privilege and household-level measures of wealth are associated with well-being. Our findings indicate a significant relationship between ethnic privilege, gender opportunity and income on life satisfaction. The results from this study provide valuable data and implications for lower income countries to identify and reduce modifiable risk factors that affect a population’s well-being.
ContributorsChavez Lopez, Giselle (Co-author, Co-author) / Hruschka, Daniel (Thesis director) / Gonzales, Angela (Committee member) / School of Molecular Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Spasticity is a neurological disorder in which a target group of muscles remain in a contracted state. In addition to interfering with the function of these muscles, spasticity causes chronic pain and discomfort. Often found in patients with cerebral palsy, multiple sclerosis, or stroke history, spasticity affects an estimated twelve million people worldwide. Not only does spasticity cause discomfort and loss of function, but the condition can lead to contractures, or permanent shortenings of the muscle and connective tissue, if left untreated. Current treatments for spasticity are primarily different forms of muscle relaxant pharmaceuticals. Almost all of these drugs, however, carry unwanted side effects, including total muscle weakness, liver toxicity, and possible dependence. Additionally, kinesiotherapy, conducted by physical therapists at rehabilitation clinics, is often prescribed to people suffering from spasticity. Since kinesiotherapy requires frequent practice to be effective, proper treatment requires constant professional care and clinic appointments, discouraging patient compliance. Consequently, a medical device that could automate relief for spasticity outside of a clinic is desired in the market. While a number of different dynamic splints for hand spasticity are currently on the market, research has shown that these devices, which simply brace the hand in an extended position, do not work through any mechanism to decrease spastic tension over time. Two methods of temporarily reducing spasticity that have been observed in clinical studies are cryotherapy, or the decrease of temperature on a target area, and electrotherapy, which is the delivery of regulated electrical pulses to a target area. It is possible that either of these mechanisms could be incorporated into a medical device aimed toward spastic relief. In fact, electrotherapy is used in a current market device called the SaeboStim, which is advertised to help stroke recovery and spastic reduction. The purpose of this paper is to evaluate the viability of a potential spastic relief device that utilizes cryotherapy to a current and closest competitor, the SaeboStim. The effectiveness of each device in relieving spasticity is reviewed. The two devices are also compared on their ability to address primary customer needs, such as convenience, ease of use, durability, and price. Overall, it is concluded that the cryotherapy device more effectively relieves hand spasticity in users, although the SaeboStim's smaller size and better convenience gives it market appeal, and reveals some of the shortcomings in the preliminary design of the cryotherapy device.
ContributorsWiedeman, Christopher Blaise (Author) / Kleim, Jeffrey (Thesis director) / Buneo, Christopher (Committee member) / W.P. Carey School of Business (Contributor) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Cocaine is a powerful psychomotor stimulant that can affect serotonin (5HT), dopamine, and norepinephrine systems in the brain. Previous studies with 5HT1B receptor agonist, CP94253, have shown dose-dependent decreases in cocaine-self administration in male rats during maintenance. However, these studies do not take into consideration sex differences between male rats and female rats. Female rats introduce a new complexity because they constantly undergo an estrous cycle that consists of four phases, metestrus, diestrus, proestrus, and estrus. It was hypothesized that cocaine infusions and active lever response rates would greatly decrease during proestrus and estrus in comparison to metestrus and diestrus due to hormonal level differences of LH, FSH, progesterone, and estradiol. In this study, female rats were trained to self-administer a training dose of 0.75 mg/kg/infusion on a fixed progressive ratio (FR5). Rats were then pretreated with CP94253 to test the effects of this 5HT1B agonist on female rat cocaine self-administration during the estrous cycle. Results showed there was no three-way interaction between cycle phase, pretreatment, and cocaine dose on infusions or active lever responses. However, pretreatment with CP94253 decreased cocaine intake and active lever responses at high cocaine doses, regardless of cycle phase. Lastly, there was a two-way interaction between pretreatment and cycle phase in which active lever responses decreased during diestrus and proestrus. These results imply that CP94253 enhances cocaine's effect regardless of cycle phase. Future work can work with ovariectomized (OVX) female rats to observe cocaine self-administration during controlled cycle phases.
ContributorsNguyen, Toan Thai Tran (Author) / Neisewander, Janet (Thesis director) / Gipson-Reichardt, Cassandra (Committee member) / Scott, Samantha (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Vagal Nerve Stimulation (VNS) has been shown to be a promising therapeutic technique in treating many neurological diseases, including epilepsy, stroke, traumatic brain injury, and migraine headache. The mechanisms by which VNS acts, however, are not fully understood but may involve changes in cerebral blood flow. The vagus nerve plays a significant role in the regulation of heart rate and cerebral blood flow that are altered during VNS. Here, we examined the effects of acute vagal nerve stimulation on both heart rate and cerebral blood flow. Laser Speckle Contrast Analysis (LASCA) was used to analyze the cerebral blood flow of male Long\u2014Evans rats. Results showed two distinct patterns of responses whereby animals either experienced a mild or severe decrease in heart rate during VNS. Further, animals that displayed mild heart rate decreases showed an increase in cerebral blood flow that persisted beyond VNS. Animals that displayed severe decreases showed a transient decrease in cerebral blood flow followed by an increase that was greater than that observed in mild animals but progressively decreased after VNS. The results suggest two distinct patterns of changes in both heart rate and cerebral blood flow that may be related to the intensity of VNS.
ContributorsHillebrand, Peter Timothy (Author) / Kleim, Jeffrey (Thesis director) / Helms Tillery, Stephen (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Higher plant Rubisco activase (Rca) is a stromal ATPase responsible for reactivating Rubisco. It is a member of the AAA+ protein superfamily and is thought to assemble into closed-ring hexamers like other AAA+ proteins belonging to the classic clade. Progress towards modeling the interaction between Rca and Rubisco has been slow due to limited structural information on Rca. Previous efforts in the lab were directed towards solving the structure of spinach short-form Rca using X-ray crystallography, given that it had notably high thermostability in the presence of ATP-γS, an ATP analog. However, due to disorder within the crystal lattice, an atomic resolution structure could not be obtained, prompting us to move to negative stain electron microscopy (EM), with our long-term goal being the use of cryo-electron microscopy (cryo-EM) for atomic resolution structure determination. Thus far, we have screened different Rca constructs in the presence of ATP-γS, both the full-length β-isoform and truncations containing only the AAA+ domain. Images collected on preparations of the full-length protein were amorphous, whereas images of the AAA+ domain showed well-defined ring-like assemblies under some conditions. Procedural adjustments, such as the use of previously frozen protein samples, rapid dilution, and minimizing thawing time were shown to improve complex assembly. The presence of Mn2+ was also found to improve hexamer formation over Mg2+. Calculated class averages of the AAA+ Rca construct in the presence of ATP-γS indicated a lack of homogeneity in the assemblies, showing both symmetric and asymmetric hexameric rings. To improve structural homogeneity, we tested buffer conditions containing either ADP alone or different ratios of ATP-γS to ADP, though results did not show a significant improvement in homogeneity. Multiple AAA+ domain preparations were evaluated. Because uniform protein assembly is a major requirement for structure solution by cryo-EM, more work needs to be done on screening biochemical conditions to optimize homogeneity.
ContributorsHernandez, Victoria Joan (Author) / Wachter, Rebekka (Thesis director) / Chiu, Po-Lin (Committee member) / Redding, Kevin (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Objective
The objective of this study is to compare amyloid β (Aβ) PET positive and negative patients to their neuropsychological profiles. There is a definitive link between Aβ deposits and cognitive disorders such as MCI or Alzheimer’s disease (AD), but does its presence justify the costly imaging tests based on its clinical context?
Background
Amnestic MCI is largely considered prodromal to AD/dementia in a high majority of cases. [1] Many studies have shown a positive correlation between Aβ PET positive individuals and their likelihood to progress to AD. Aβ deposits in the brain are not always a sign of AD or even MCI, and many elderly people live normal lives with elevated levels. The presence of Aβ in the brain should be carefully considered alongside other tests before making a clinical diagnosis of MCI or AD.
Methods
130 subjects from Barrow Neurological Institute (Phoenix, AZ) were included in this study. Amyloid PET report data was pulled from Dignity Health St. Joseph’s Hospital and Medical Center Outpatient Imaging. Amyloid PET scans obtained by using F-18 florbetapir compound and reviewed by an expert radiologist providing a qualitative status of amyloid-beta positive (+) or negative (-). All data was anonymized and categorized into positive amyloid PET, negative amyloid PET, and clinical diagnosis based on neuropsychological profiles.
Results
The demographic data indicated that 38.5% of the 91 patients diagnosed as amnestic MCI were amyloid PET negative while 61.5% were amyloid PET positive. Of the 39 patients diagnosed as Dementia or AD 15.4% were amyloid PET negative and 84.6% were amyloid PET positive. Correlational analysis between diagnosis and neuropsychological variables suggests that some variables correlate well while others do not. There is a significant correlation between diagnosis and dementia rating scale (DRS) r(24) = -.762, between diagnosis and TrailsB Test r(39) = .397, between diagnosis and phonetic fluency r(30) = -.383, between diagnosis and semantic fluency r(29) = -.369, and between diagnosis and the Boston Naming Test (BNT) r(36) = -.312. Comparing the PET positive and PET negative groups there is a marginal significance in the Boston Naming Test (T=1.945, P=.060) suggesting PET positive individuals test lower than PET negative.
Conclusion
Based on all the results of this study, amyloid PET is still a clinical indicator that an individual might be MCI or dementia/AD, but it has its exceptions. A small number of patients diagnosed as dementia/AD had a negative amyloid PET suggesting that beta amyloid plaques are not the only cause of the disease. There is a strong suggestion that amyloid plaques are a major factor in the progression of dementia or AD, however the results from an amyloid PET cannot be directly related to a diagnosis.
The objective of this study is to compare amyloid β (Aβ) PET positive and negative patients to their neuropsychological profiles. There is a definitive link between Aβ deposits and cognitive disorders such as MCI or Alzheimer’s disease (AD), but does its presence justify the costly imaging tests based on its clinical context?
Background
Amnestic MCI is largely considered prodromal to AD/dementia in a high majority of cases. [1] Many studies have shown a positive correlation between Aβ PET positive individuals and their likelihood to progress to AD. Aβ deposits in the brain are not always a sign of AD or even MCI, and many elderly people live normal lives with elevated levels. The presence of Aβ in the brain should be carefully considered alongside other tests before making a clinical diagnosis of MCI or AD.
Methods
130 subjects from Barrow Neurological Institute (Phoenix, AZ) were included in this study. Amyloid PET report data was pulled from Dignity Health St. Joseph’s Hospital and Medical Center Outpatient Imaging. Amyloid PET scans obtained by using F-18 florbetapir compound and reviewed by an expert radiologist providing a qualitative status of amyloid-beta positive (+) or negative (-). All data was anonymized and categorized into positive amyloid PET, negative amyloid PET, and clinical diagnosis based on neuropsychological profiles.
Results
The demographic data indicated that 38.5% of the 91 patients diagnosed as amnestic MCI were amyloid PET negative while 61.5% were amyloid PET positive. Of the 39 patients diagnosed as Dementia or AD 15.4% were amyloid PET negative and 84.6% were amyloid PET positive. Correlational analysis between diagnosis and neuropsychological variables suggests that some variables correlate well while others do not. There is a significant correlation between diagnosis and dementia rating scale (DRS) r(24) = -.762, between diagnosis and TrailsB Test r(39) = .397, between diagnosis and phonetic fluency r(30) = -.383, between diagnosis and semantic fluency r(29) = -.369, and between diagnosis and the Boston Naming Test (BNT) r(36) = -.312. Comparing the PET positive and PET negative groups there is a marginal significance in the Boston Naming Test (T=1.945, P=.060) suggesting PET positive individuals test lower than PET negative.
Conclusion
Based on all the results of this study, amyloid PET is still a clinical indicator that an individual might be MCI or dementia/AD, but it has its exceptions. A small number of patients diagnosed as dementia/AD had a negative amyloid PET suggesting that beta amyloid plaques are not the only cause of the disease. There is a strong suggestion that amyloid plaques are a major factor in the progression of dementia or AD, however the results from an amyloid PET cannot be directly related to a diagnosis.
ContributorsSorenson, Keaton Andrew (Author) / Azuma, Tamiko (Thesis director) / DeCourt, Boris (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The goal of this study was to investigate the possibility of catch bond formation between nectin and actin during cellular adhesion by modeling the actin-filament binding protein, afadin, out of equilibrium. This was done through the in silico methodology of Molecular Dynamics (MD); more specifically using Steered Molecular Dynamics (SMD) and Replica Exchange Molecular Dynamics (REMD). The methodology of this experiment centered around generating physiologically probable structures through REMD, then using MD and SMD methods to generate structures in the absence and presence of force respectively. These structures were then analyzed through Solvent Accessible Surface Area (SASA) measurements to assess the overall compactness of the structure, which led to implicit observations on the overall resistance of force that this structure has. Overall, it was found that the structure displayed more compact conformations in the presence of force as the SASA values of the binding pocket and individual residues involved in the system tend to decrease as force was applied. This is indicative of more stable conformations and a force resistant quality that is indicative of catch bonding, thus leading to the natural conclusion that this structure displays catch bond character.
ContributorsChapman, Jonathan (Author) / Singharoy, Abhishek (Thesis director) / Beckstein, Oliver (Committee member) / Ros, Robert (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2024-05
Description
The primary channel responsible for cold thermo-transduction in mammals is the transient receptor potential melastatin 8 (TRPM8) channel. TRPM8 is a polymodal, nonselective cation channel with an activation that is dependent on a variety of signals, including the membrane potential, calcium concentration, temperature, and ligands such as menthol. Mathematical modeling provides valuable insight into biochemical phenomena, such as the activity of these channels, which are difficult to observe experimentally. Here, we propose a TRPM8 gating model, represented as a system of ordinary differential equations with menthol, calcium, voltage, and temperature dependencies. We use voltage-clamp data from transfected HEK293 cells in the presence of menthol to create a menthol-dependent voltage shift of activation. We fit the parameters of the TRPM8 gating model to replicate experimental TRPM8 transfected HEK293 cell voltage clamp electrophysiology data using a genetic algorithm. Using k-means clustering, we note eight clusters within 110 total parameter sets consisting of parameter solutions that provide a good fit to the experimental data. We then replicate novel fixed-voltage temperature ramp and fixed-temperature voltage ramp experimental data, demonstrating that our model can replicate the dynamic behaviors of TRPM8. With this TRPM8 gating model, we analyze the various parameter sets obtained from the genetic algorithm and find that different parameter combinations of calcium decay, calcium voltage shift of activation, and temperature sensitivity are able to match static voltage clamp data although differ in their effects on hysteresis and maximal current within prolonged temperature ramp simulations.
ContributorsDudebout, Eric (Author) / Crook, Sharon (Thesis director) / Van Horn, Wade (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2024-05
Description
As an incoming STEM student, it can be intimidating thinking about the long academic road ahead. That is why I have written a short book about my greatest success strategies and takeaways from my past four years as a STEM student. I dive into topics including communication, teamwork, time management, growth mindsets, and self-care.
ContributorsConway, Kayla (Author) / Reeves, Scott (Thesis director) / del Mar Navarro, María (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2024-05
DescriptionIn this project we explored the possibility of creating an international student festival here at ASU through interviews and research. We compiled together everything that would be needed to run such an event efficiently and properly.
ContributorsLacno, James (Author) / Coleman, Audrey (Co-author) / Seagrave, Adam (Thesis director) / Bhatti-Klug, Renee (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor)
Created2024-05