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Description
Down Syndrome (DS), caused by the trisomy 21, is the most common intellectual developmental disorder. Children with DS display deficits in ample memory tasks attributed to alterations in memory-related brain structures, including the hippocampus. Although, many studies in DS focused on development of the brain during prenatal stages, little

Down Syndrome (DS), caused by the trisomy 21, is the most common intellectual developmental disorder. Children with DS display deficits in ample memory tasks attributed to alterations in memory-related brain structures, including the hippocampus. Although, many studies in DS focused on development of the brain during prenatal stages, little is known about the cellular evolution of the hippocampus in postnatal periods in DS. Therefore, here we examined the neurochemical spatiotemporal development of neuronal profiles in pediatric postnatal hippocampus in DS and neurotypical developing (NTD) controls. A quantitative and qualitative neuronal distribution was performed in hippocampal sections containing the proper hippocampus, dentate gyrus (DG) and subiculum obtained at autopsy from 1 day to 3 year-old infants in DS and NTD age-matched controls using antibodies against the non-phosphorylated high-molecular-weight neurofilament, a marker of differentiated neurons (SMI-32), the calcium binding protein calbindin D-28k (CAB), and the migration neuronal marker microtubule-associated protein doublecortin (DCX). In addition, Aβ and phosphorylated tau was also immunohistochemically examined in the hippocampus using 6E10, Aβ1-42 and the phosphorylated CP-13 and AT8 tau antibodies, respectively. We found APP/Aβ immunoreactivity, but not Aβ1-42, in diffuse-like plaques in the hippocampus from 1 day to 3 year old infants and young children in DS and NTD cases. By contrast, phosphorylated fetal tau was not immunodetected in the hippocampus at any age in both groups. SMI-32 immunolabeled neurons were observed in the hilus, CA2 field and subiculum in early postnatal cases in DS and NTD. The number of SMI-32 immunoreactive (ir) granule cells in the DG were significantly decreased in DS compared to NTD. While a strong DCX immunoreactivity was observed in the granule cells of the DG in the hippocampus in both groups at early postnatal stages, a more accelerated reduction was observed in DS. CAB-ir neuronal distribution in the postnatal hippocampus was comparable between the youngest and the oldest infants in NTD and DS. In addition, strong positive correlations were observed between DG-DCX-ir cells numbers and both DG-CAB-ir and DG-SMI-32-ir values as well as negative correlations between the brain weight and DG granule cell-ir numbers for all markers in DS. These findings suggest that neuronal maturation and migration in the hippocampus are compromised in early postnatal stages of the development in DS and may contribute to the intellectual disabilities observed in this group.
ContributorsMoreno, David (Co-author) / Perez, Sylvia E. (Co-author, Thesis director) / Velazquez, Ramon (Thesis director) / Schafernak, Kristian T. (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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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

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
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Description
Immunology, the study of the immune system and its ability to distinguish self from non-self, is a rapidly advancing sector of molecular biology. Cancer, being host derived, provides a difficult challenge for immune cells to distinguish it from normal tissue. The historic treatment of cancer has had three main methods:

Immunology, the study of the immune system and its ability to distinguish self from non-self, is a rapidly advancing sector of molecular biology. Cancer, being host derived, provides a difficult challenge for immune cells to distinguish it from normal tissue. The historic treatment of cancer has had three main methods: radiation, chemotherapy, and surgery (1). Due to recent advancements in understanding the regulatory role of adaptive immunity against cancer, researchers have been attempting to engineer therapies to enhance patients’ immunities against their cancer. Immunotherapies, both passive and active, demonstrate potential for combating many diseases. Passive immunization provides temporary protection against a pathogen, whereas active immunization teaches the patient’s system to respond to the antigen independently, giving life-long immunity. Passive immunization, generally, is a much more expensive method of providing immunity and is commonly used in emergency situations. Anti-venom, for example, uses antibodies grown in lab to neutralize venom. Examples of active immunization are vaccines, which mimic the wild-type pathogen in a way that elicits an immune response, specifically naïve lymphocyte activation and maturation into memory lymphocytes. In terms of cancer therapy, both passive and active immunization are being tested for efficacy (2).
ContributorsMarquardt, Charles Andrew (Author) / Anderson, Karen S. (Thesis director) / Mason, Hugh S. (Committee member) / Lake, Douglas F. (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Background: Despite a multitude of health initiatives, obesity rates in America have continued to increase yearly, with obese or overweight people making up two-thirds of the population. Due to a lack of significant results from diet and weight-loss medication, new methods of weight-loss are increasingly considered. This paper looks beyond

Background: Despite a multitude of health initiatives, obesity rates in America have continued to increase yearly, with obese or overweight people making up two-thirds of the population. Due to a lack of significant results from diet and weight-loss medication, new methods of weight-loss are increasingly considered. This paper looks beyond traditional Western treatments for weight loss and will analyze views and treatments for overweight and obesity in traditional Chinese medicine (TCM).
Methods: Three databases were used to search for papers published after 2010 until October 2019 discussing obesity, overweight and TCM. No forms of Chinese medicine were excluded from the search. Studies were excluded if they did not meet the date criteria or if they overlapped with papers found in other databases.
Results: Six of the selected papers covered acupuncture (electro, balance or catgut embedding acupuncture methods) either jointly with other treatments or alone, one exclusively on moxibustion and three studies on three different types of TCM herbal medicine. Each study showed a statistically significant effect on body mass index (BMI) value decrease or total weight loss (TWL). The six acupuncture papers all showed statistical significance at the 95% CI against control groups (sham acupuncture or no acupuncture) and against before-treatment BMI values or TWL values.
Conclusion: Of the treatments reviewed, almost all acupuncture studies were shown to be consistently effective in treating overweight or obese individuals within this selection of studies, as well as in another meta-analysis. This may be due to acupuncture’s ties to a neuroendocrine mechanism. Future studies should further explore the neuroendocrine connection between acupuncture and weight loss. Herbal medication was also shown to have a significant effect in reducing weight in each study; however, two studies used mice or rats as subjects, therefore understanding the effects on human subjects is limited.
ContributorsTung, Kiram Yeo (Author) / Lateef, Dalya (Thesis director) / Capco, David (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Abiotic stresses, such as heat, can drive protein misfolding and aggregation, leading to inhibition of cellular function and ultimately cell death. Unexpectedly, a thermotolerant Escherichia coli was identified from a pool of antibiotic resistant RNA polymerase β subunit (rpoB) mutants. This stress tolerant phenotype was characterized through exposure to high

Abiotic stresses, such as heat, can drive protein misfolding and aggregation, leading to inhibition of cellular function and ultimately cell death. Unexpectedly, a thermotolerant Escherichia coli was identified from a pool of antibiotic resistant RNA polymerase β subunit (rpoB) mutants. This stress tolerant phenotype was characterized through exposure to high temperature and ethanol. After 30-minute exposure of cells to 55°C or 25% ethanol, the mutant displayed 100 times greater viability than the wild-type, indicating that the rpoB mutation may have broadly affected the cellular environment to reduce protein misfolding and/or prevent protein aggregation. To further test this hypothesis, we examined thermotolerance of cells lacking heat shock chaperone DnaJ (Hsp40), which is a cochaperone of one of the most abundant and conserved chaperones, DnaK (Hsp70). The deletion of dnaJ led to severe growth defects in the wild-type, namely a slower growth rate and extreme filamentation at 42°C. The severity of the growth defects increased after additionally deleting DnaJ analog, CbpA. However, these defects were significantly ameliorated by the rpoB mutation. Finally, the rpoB mutant was found to be minimally affected by the simultaneous depletion of DnaK and DnaJ compared to the wild-type, which failed to form single colonies at 37°C and 42°C. Based on these observations, it is proposed that the rpoB mutant’s robust thermotolerant phenotype results from a cellular environment protective against protein aggregation or improper folding. The folding environment of the rpoB mutants should be further examined to elucidate the mechanism by which both antibiotic resistance and thermotolerance can be conferred.
ContributorsYeh, Melody (Author) / Misra, Rajeev (Thesis director) / Wang, Xuan (Committee member) / Kelly, Keilen (Committee member) / School of Life Sciences (Contributor) / School of International Letters and Cultures (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Spaceflight and spaceflight analogue culture enhance the virulence and pathogenesis-related stress resistance of the foodborne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium). This is an alarming finding as it suggests that astronauts may have an increased risk of infection during spaceflight. This risk is further exacerbated as multiple studies indicate

Spaceflight and spaceflight analogue culture enhance the virulence and pathogenesis-related stress resistance of the foodborne pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium). This is an alarming finding as it suggests that astronauts may have an increased risk of infection during spaceflight. This risk is further exacerbated as multiple studies indicate that spaceflight negatively impacts aspects of the immune system. In order to ensure astronaut safety during long term missions, it is important to study the phenotypic effects of the microgravity environment on a range of medically important microbial pathogens that might be encountered by the crew. This ground-based study uses the NASA-engineered Rotating Wall Vessel (RWV) bioreactor as a spaceflight analogue culture system to grow bacteria under low fluid shear forces relative to those encountered in microgravity, and interestingly, in the intestinal tract during infection. The culture environment in the RWV is commonly referred to as low shear modeled microgravity (LSMMG). In this study, we characterized the stationary phase stress response of the enteric pathogen, Salmonella enterica serovar Enteritidis (S. Enteritidis), to LSMMG culture. We showed that LSMMG enhanced the resistance of stationary phase cultures of S. Enteritidis to acid and thermal stressors, which differed from the LSSMG stationary phase response of the closely related pathovar, S. Typhimurium. Interestingly, LSMMG increased the ability of both S. Enteritidis and S. Typhimurium to adhere to, invade into, and survive within an in vitro 3-D intestinal co-culture model containing immune cells. Our results indicate that LSMMG regulates pathogenesis-related characteristics of S. Enteritidis in ways that may present an increased health risk to astronauts during spaceflight missions.
ContributorsKoroli, Sara (Author) / Nickerson, Cheryl (Thesis director) / Barrila, Jennifer (Committee member) / Ott, C. Mark (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Transcranial Current Stimulation (TCS) is a long-established method of modulating neuronal activity in the brain. One type of this stimulation, transcranial alternating current stimulation (tACS), is able to entrain endogenous oscillations and result in behavioral change. In the present study, we used five stimulation conditions: tACS at three different frequencies

Transcranial Current Stimulation (TCS) is a long-established method of modulating neuronal activity in the brain. One type of this stimulation, transcranial alternating current stimulation (tACS), is able to entrain endogenous oscillations and result in behavioral change. In the present study, we used five stimulation conditions: tACS at three different frequencies (6Hz, 12Hz, and 22Hz), transcranial random noise stimulation (tRNS), and a no-stimulation sham condition. In all stimulation conditions, we recorded electroencephalographic data to investigate the link between different frequencies of tACS and their effects on brain oscillations. We recruited 12 healthy participants. Each participant completed 30 trials of the stimulation conditions. In a given trial, we recorded brain activity for 10 seconds, stimulated for 12 seconds, and recorded an additional 10 seconds of brain activity. The difference between the average oscillation power before and after a stimulation condition indicated change in oscillation amplitude due to the stimulation. Our results showed the stimulation conditions entrained brain activity of a sub-group of participants.
ContributorsChernicky, Jacob Garrett (Author) / Daliri, Ayoub (Thesis director) / Liss, Julie (Committee member) / School of Life Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Although the interpersonal (e.g., deceitful, manipulative, grandiose) and affective (e.g., lack of empathy/guilt) features of adult psychopathy have been associated with an increased risk for criminal activity (Boccio & Beaver, 2018; Hare, 1993; Porter, Birt, & Boer, 2001), there remains a subgroup of individuals with these features who are able

Although the interpersonal (e.g., deceitful, manipulative, grandiose) and affective (e.g., lack of empathy/guilt) features of adult psychopathy have been associated with an increased risk for criminal activity (Boccio & Beaver, 2018; Hare, 1993; Porter, Birt, & Boer, 2001), there remains a subgroup of individuals with these features who are able to avoid being convicted of a serious crime. However, it remains unclear what factors differentiate individuals with high psychopathic traits who are convicted for serious offending from those who are not convicted. To address this gap, the current study aims to answer the following: 1.) Do economic, social, or intelligence factors differentiate convicted versus non-convicted individuals with high psychopathic traits? and 2.) Are non-convicted individuals with high psychopathic traits less likely to engage in self-report offending than convicted individuals with these traits? Data was drawn from the youngest and oldest cohorts of the Pittsburgh Youth Study (N=806), a longitudinal study that followed adolescent (ages 13-16) males from Pittsburgh, PA over 22 years in order to examine the development of delinquency, substance use, and mental health problems. Significant between-group differences were examined using ANOVA and chi-squared analyses. Results showed no difference between convicted and non-convicted men with high psychopathic traits in terms of intelligence or relationship quality. However, non-convicted men with high psychopathic traits were more likely to be employed and less likely to be on public assistance that men with high psychopathic traits. Further, high psychopathic trait non-convicted men were less likely to report adult offending than their convicted counterparts, but were more likely to offend than men with low psychopathic traits who were not convicted. These results suggest that men with high psychopathic traits who elude conviction exhibit better adult adjustment than men with these characteristics that have been convicted, even though they report engaging in adult offending.
ContributorsKrob, Casaundra Kendal (Author) / Pardini, Dustin (Thesis director) / Sweeten, Gary (Committee member) / School of Life Sciences (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Analyzing human DNA sequence data allows researchers to identify variants associated with disease, reconstruct the demographic histories of human populations, and further understand the structure and function of the genome. Identifying variants in whole genome sequences is a crucial bioinformatics step in sequence data processing and can be performed using

Analyzing human DNA sequence data allows researchers to identify variants associated with disease, reconstruct the demographic histories of human populations, and further understand the structure and function of the genome. Identifying variants in whole genome sequences is a crucial bioinformatics step in sequence data processing and can be performed using multiple approaches. To investigate the consistency between different bioinformatics methods, we compared the accuracy and sensitivity of two genotyping strategies, joint variant calling and single-sample variant calling. Autosomal and sex chromosome variant call sets were produced by joint and single-sample calling variants for 10 female individuals. The accuracy of variant calls was assessed using SNP array genotype data collected from each individual. To compare the ability of joint and single-sample calling to capture low-frequency variants, folded site frequency spectra were constructed from variant call sets. To investigate the potential for these different variant calling methods to impact downstream analyses, we estimated nucleotide diversity for call sets produced using each approach. We found that while both methods were equally accurate when validated by SNP array sites, single-sample calling identified a greater number of singletons. However, estimates of nucleotide diversity were robust to these differences in the site frequency spectrum between call sets. Our results suggest that despite single-sample calling’s greater sensitivity for low-frequency variants, the differences between approaches have a minimal effect on downstream analyses. While joint calling may be a more efficient approach for genotyping many samples, in situations that preclude large sample sizes, our study suggests that single-sample calling is a suitable alternative.
ContributorsHowell, Emma (Co-author) / Wilson, Melissa (Thesis director) / Stone, Anne (Committee member) / Phung, Tanya (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Objective: To provide insight into the World Health Organization SAGE Working Group Vaccine Hesitancy Survey by applying the tool to populations across Maricopa County, Arizona. Design: An online survey was conducted using the Qualtrics Survey Software, of individuals residing in Maricopa County, Arizona during the month of October 2019. Results:

Objective: To provide insight into the World Health Organization SAGE Working Group Vaccine Hesitancy Survey by applying the tool to populations across Maricopa County, Arizona. Design: An online survey was conducted using the Qualtrics Survey Software, of individuals residing in Maricopa County, Arizona during the month of October 2019. Results: Of 209 respondents, the followed demonstrated to be the top 3 reasons for either having not received the flu shot yet or having not planned to receive the flu shot: “I’m healthy, I don’t need it”(20.1%); “Worried I might get the flu from it”(17.7%); “I don’t think it works”(17.7%) Statistical analysis demonstrated that vaccine hesitant and non-hesitant respondents are likely to respond differently to topics covering: safety of vaccines; self-perceived health status; importance of the flu shot among one’s peers; flu vaccine related knowledge Conclusions: The WHO VHS applied to the population of Maricopa County, Arizona reported little hesitancy towards the seasonal flu vaccine. Statistical analysis of Vaccine Hesitant respondents vs. Non-Hesitant respondents demonstrates that specified public health education focused on the immunological implications of vaccines may be needed for the hesitant population to gain confidence in vaccine efficacy. A more diverse respondent group that consists of residents beyond the county lines of Maricopa is needed to understand the full scope of vaccine hesitancy that exists in Arizona.
ContributorsMaroofi, Hanna (Co-author, Co-author) / Jehn, Megan (Thesis director) / Muabyi, Anuj (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05