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- Creators: Marine Biological Laboratory Archives
Description
The goal of the studies described in this thesis was to determine the changes in vascular density in the paraventricular nucleus (PVN) of the hypothalamus following prenatal exposure to the synthetic glucocorticoid hormone, dexamethasone (DEX). DEX is a synthetic glucocorticoid used clinically in women at risk for preterm delivery or in preterm infants to promote proper pulmonary development in high-risk neonates. Prenatal exposure to glucocorticoids such as DEX may change the development of important brain regulatory centers such as the PVN, resulting in increased risk for diseases in adulthood.
Previous studies have demonstrated that the hypothalamus regulates neuroendocrine and autonomic function and behavior. Within the hypothalamus, the paraventricular nucleus (PVN) is an integratory node that contains neurons associated with the control of neuroendocrine and autonomic responses. The PVN also has one of the highest density of blood vessels within the brain. Alterations of normal PVN angiogenesis by dexamethasone could potentially result in long-term modifications of brain and endocrine functions.
Timed-pregnant Sprague Dawley female rats received DEX on gestational days 18-21 and the resulting progeny were sacrificed at Postnatal Day (PND) 0, 4, 14, and 21. A tomato lectin, Lycopersicon Esculentum labeled with DyLight594 was used to stain blood vessels in the PVN and scanning confocal microscopy was used to analyze the experimental brains for PVN blood vessel density
Analysis of data using a 3-way analysis of variance (ANOVA) with age, sex and treatment as main factors, showed a significant age effect in vascular density. Analysis of female data by 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A Student‘s t-test of a planned comparison on PND2 showed a significant reduction by DEX treatment (p < 0.05). Analysis of data from females, using 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A planned comparison at PND 2 using Student’s t-test indicated a significant reduction by dex treatment.
The results of these studies demonstrate that there is significant postnatal angiogenic programming and that the vascular density of the PVN is altered by prenatal dexamethasone administration at PND2. The time-course shows developmental fluctuations in vessel density that may prove to be physiologically significant for normal brain function and developmental programming of brain and behavior.
Previous studies have demonstrated that the hypothalamus regulates neuroendocrine and autonomic function and behavior. Within the hypothalamus, the paraventricular nucleus (PVN) is an integratory node that contains neurons associated with the control of neuroendocrine and autonomic responses. The PVN also has one of the highest density of blood vessels within the brain. Alterations of normal PVN angiogenesis by dexamethasone could potentially result in long-term modifications of brain and endocrine functions.
Timed-pregnant Sprague Dawley female rats received DEX on gestational days 18-21 and the resulting progeny were sacrificed at Postnatal Day (PND) 0, 4, 14, and 21. A tomato lectin, Lycopersicon Esculentum labeled with DyLight594 was used to stain blood vessels in the PVN and scanning confocal microscopy was used to analyze the experimental brains for PVN blood vessel density
Analysis of data using a 3-way analysis of variance (ANOVA) with age, sex and treatment as main factors, showed a significant age effect in vascular density. Analysis of female data by 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A Student‘s t-test of a planned comparison on PND2 showed a significant reduction by DEX treatment (p < 0.05). Analysis of data from females, using 2-way ANOVA demonstrated a significant effect of age, but no treatment or interaction effects. Post-hoc analysis shows significant differences at PND 2, 4, 14, and 21 compared to PND0. A planned comparison at PND 2 using Student’s t-test indicated a significant reduction by dex treatment.
The results of these studies demonstrate that there is significant postnatal angiogenic programming and that the vascular density of the PVN is altered by prenatal dexamethasone administration at PND2. The time-course shows developmental fluctuations in vessel density that may prove to be physiologically significant for normal brain function and developmental programming of brain and behavior.
ContributorsWidener, Andrew John-Claude (Author) / Handa, Robert (Thesis director) / Orchinik, Miles (Committee member) / Mustard, Julie (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
A coincidence reporter construct, consisting of the p21-promoter and two luciferase genes (Firefly and Renilla), was constructed for the screening of drugs that might inhibit Olig2's tumorigenic role in glioblastoma. The reporter construct was tested using an Olig2 inhibitor, HSP990, as well as short hairpin RNA targeting Olig2. Further confirmatory analysis is needed before the reporter cell line is ready for high-throughput screening at the NIH and lead compound selection.
ContributorsCusimano, Joseph Michael (Author) / LaBaer, Joshua (Thesis director) / Mangone, Marco (Committee member) / Mehta, Shwetal (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2014-05
Description
Background
The transmission dynamics of Tuberculosis (TB) involve complex epidemiological and socio-economical interactions between individuals living in highly distinct regional conditions. The level of exogenous reinfection and first time infection rates within high-incidence settings may influence the impact of control programs on TB prevalence. The impact that effective population size and the distribution of individuals’ residence times in different patches have on TB transmission and control are studied using selected scenarios where risk is defined by the estimated or perceive first time infection and/or exogenous re-infection rates.
Methods
This study aims at enhancing the understanding of TB dynamics, within simplified, two patch, risk-defined environments, in the presence of short term mobility and variations in reinfection and infection rates via a mathematical model. The modeling framework captures the role of individuals’ ‘daily’ dynamics within and between places of residency, work or business via the average proportion of time spent in residence and as visitors to TB-risk environments (patches). As a result, the effective population size of Patch i (home of i-residents) at time t must account for visitors and residents of Patch i, at time t.
Results
The study identifies critical social behaviors mechanisms that can facilitate or eliminate TB infection in vulnerable populations. The results suggest that short-term mobility between heterogeneous patches contributes to significant overall increases in TB prevalence when risk is considered only in terms of direct new infection transmission, compared to the effect of exogenous reinfection. Although, the role of exogenous reinfection increases the risk that come from large movement of individuals, due to catastrophes or conflict, to TB-free areas.
Conclusions
The study highlights that allowing infected individuals to move from high to low TB prevalence areas (for example via the sharing of treatment and isolation facilities) may lead to a reduction in the total TB prevalence in the overall population. The higher the population size heterogeneity between distinct risk patches, the larger the benefit (low overall prevalence) under the same “traveling” patterns. Policies need to account for population specific factors (such as risks that are inherent with high levels of migration, local and regional mobility patterns, and first time infection rates) in order to be long lasting, effective and results in low number of drug resistant cases.
The transmission dynamics of Tuberculosis (TB) involve complex epidemiological and socio-economical interactions between individuals living in highly distinct regional conditions. The level of exogenous reinfection and first time infection rates within high-incidence settings may influence the impact of control programs on TB prevalence. The impact that effective population size and the distribution of individuals’ residence times in different patches have on TB transmission and control are studied using selected scenarios where risk is defined by the estimated or perceive first time infection and/or exogenous re-infection rates.
Methods
This study aims at enhancing the understanding of TB dynamics, within simplified, two patch, risk-defined environments, in the presence of short term mobility and variations in reinfection and infection rates via a mathematical model. The modeling framework captures the role of individuals’ ‘daily’ dynamics within and between places of residency, work or business via the average proportion of time spent in residence and as visitors to TB-risk environments (patches). As a result, the effective population size of Patch i (home of i-residents) at time t must account for visitors and residents of Patch i, at time t.
Results
The study identifies critical social behaviors mechanisms that can facilitate or eliminate TB infection in vulnerable populations. The results suggest that short-term mobility between heterogeneous patches contributes to significant overall increases in TB prevalence when risk is considered only in terms of direct new infection transmission, compared to the effect of exogenous reinfection. Although, the role of exogenous reinfection increases the risk that come from large movement of individuals, due to catastrophes or conflict, to TB-free areas.
Conclusions
The study highlights that allowing infected individuals to move from high to low TB prevalence areas (for example via the sharing of treatment and isolation facilities) may lead to a reduction in the total TB prevalence in the overall population. The higher the population size heterogeneity between distinct risk patches, the larger the benefit (low overall prevalence) under the same “traveling” patterns. Policies need to account for population specific factors (such as risks that are inherent with high levels of migration, local and regional mobility patterns, and first time infection rates) in order to be long lasting, effective and results in low number of drug resistant cases.
ContributorsMoreno Martinez, Victor (Author) / Espinoza Cortes, Baltazar (Author) / Barley, Kamal (Author) / Paredes Gutierrez, Marlio (Author) / Bichara, Derdei (Author) / Mubayi, Anuj (Author) / Castillo-Chavez, Carlos (Author) / Simon M. Levin Mathematical, Computational and Modeling Sciences Center (Contributor) / College of Liberal Arts and Sciences (Contributor) / School of Human Evolution and Social Change (Contributor)
Created2017-01-11
Description
Serial femtosecond crystallography (SFX) using X-ray free-electron laser sources is an emerging method with considerable potential for time-resolved pump-probe experiments. Here we present a lipidic cubic phase SFX structure of the light-driven proton pump bacteriorhodopsin (bR) to 2.3 Å resolution and a method to investigate protein dynamics with modest sample requirement. Time-resolved SFX (TR-SFX) with a pump-probe delay of 1 ms yields difference Fourier maps compatible with the dark to M state transition of bR. Importantly, the method is very sample efficient and reduces sample consumption to about 1 mg per collected time point. Accumulation of M intermediate within the crystal lattice is confirmed by time-resolved visible absorption spectroscopy. This study provides an important step towards characterizing the complete photocycle dynamics of retinal proteins and demonstrates the feasibility of a sample efficient viscous medium jet for TR-SFX.
ContributorsNogly, Przemyslaw (Author) / Panneels, Valerie (Author) / Nelson, Garrett (Author) / Gati, Cornelius (Author) / Kimura, Tetsunari (Author) / Milne, Christopher (Author) / Milathianaki, Despina (Author) / Kubo, Minoru (Author) / Wu, Wenting (Author) / Conrad, Chelsie (Author) / Coe, Jesse (Author) / Bean, Richard (Author) / Zhao, Yun (Author) / Bath, Petra (Author) / Dods, Robert (Author) / Harimoorthy, Rajiv (Author) / Beyerlein, Kenneth R. (Author) / Rheinberger, Jan (Author) / James, Daniel (Author) / Deponte, Daniel (Author) / Li, Chufeng (Author) / Sala, Leonardo (Author) / Williams, Garth J. (Author) / Hunter, Mark S. (Author) / Koglin, Jason E. (Author) / Berntsen, Peter (Author) / Nango, Eriko (Author) / Iwata, So (Author) / Chapman, Henry N. (Author) / Fromme, Petra (Author) / Frank, Matthias (Author) / Abela, Rafael (Author) / Boutet, Sebastien (Author) / Barty, Anton (Author) / White, Thomas A. (Author) / Weierstall, Uwe (Author) / Spence, John (Author) / Neutze, Richard (Author) / Schertler, Gebhard (Author) / Standfuss, Jorg (Author) / College of Liberal Arts and Sciences (Contributor) / Department of Physics (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Biodesign Institute (Contributor) / Applied Structural Discovery (Contributor) / School of Molecular Sciences (Contributor)
Created2016-08-22
Description
The effects of meditation on attention control have been widely studied in recent years. However, the methodological flaws of many of these studies raise serious concerns on the validity of meditation training as a cognitive enhancer. This study investigated the near and far transfer effects of mindfulness meditation training on attention control when a stringent experimental design was implemented. Participants in the experimental group practiced meditation for three twenty-minute sessions, and participants in the active control group listened to an audio book about meditation for similar times. No significant effect of meditation on change in performance on cognitive tasks was found. This study suggests that short-term mindfulness meditation training does not result in increased attention control.
ContributorsPatel, Sachi Rajul (Author) / Brewer, Gene (Thesis director) / Presson, Clark (Committee member) / Davis, Mary (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor) / Department of Psychology (Contributor) / School of Historical, Philosophical and Religious Studies (Contributor)
Created2013-05
Description
ASU4Food's objective is to increase the visibility of the statewide hunger crisis among Arizona State University's campuses, and to raise monetary and food donations to alleviate this issue. By collaborating with a multitude of organizations both on and off-campus, we aim to become a well-known, powerful, and stable student organization. This thesis will cover the endeavors of Elana Niren, Theresa Reckamp, and Sidath Wijetunga regarding the maintenance, growth, and expansion of ASU4Food. ASu4Food has been striving to gain connections and the reputation that would allow it to become an "umbrella organization" with the ability to coordinate all of the food-raising endeavors at ASU. The effects of our actions can be seen in the club's stability. We are now being sought out by organizations such as the Salvation Army, Sunflower Farmers Market, and Shutterfly. However, there is still more work to be done, and we hope that this thesis will act as a guide for future generation of club members and officers, and that ASU4Food will continue improving in activity and efficiency for many years to come.
ContributorsNiren, Elana (Co-author) / Reckamp, Theresa (Co-author) / Wijetunga, Sidath (Co-author) / Eaton, John (Thesis director) / Mokwa, Michael (Committee member) / Southergill, Keith (Committee member) / Barrett, The Honors College (Contributor) / Department of Chemistry and Biochemistry (Contributor)
Created2013-05
ContributorsMarine Biological Laboratory Archives (Publisher) / Arizona Board of Regents (Publisher)
Created1928
ContributorsMarine Biological Laboratory Archives (Publisher) / Arizona Board of Regents (Publisher)
ContributorsMarine Biological Laboratory Archives (Publisher) / Arizona Board of Regents (Publisher)
Created1928
ContributorsMarine Biological Laboratory Archives (Publisher) / Arizona Board of Regents (Publisher)
Created1928