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Articles 1 - 30 of 34
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The Influence Of Mir-322 On Skeletal Muscle Differentiation, Miles Alexander Soyer
The Influence Of Mir-322 On Skeletal Muscle Differentiation, Miles Alexander Soyer
Legacy Theses & Dissertations (2009 - 2024)
Skeletal muscle plays a crucial role in coordinating voluntary movement and accounts for nearly 50% of total body mass. Dysregulation in skeletal muscle development is known to cause muscle degenerative diseases including the devastating Duchenne Muscular Dystrophy (DMD). The majority of the biological studies investigating muscle development were based on myogenic transcription factors and signaling molecules including: Pax7, Myf5, MyoD, WNT, TGF-β and BMP. After the discovery of non-coding RNAs including microRNAs, it was postulated that these molecules could regulate gene expression and thus affect differentiation and development. MicroRNAs are small non-coding RNAs (~17-25 nucleotides) that regulate gene expression negatively …
An Assessment Of Combinatorial Transcription Factor Activity At P53 Enhancer Elements, Sylvia Kuang
An Assessment Of Combinatorial Transcription Factor Activity At P53 Enhancer Elements, Sylvia Kuang
Biological Sciences
Certain non-coding DNA sequences in the eukaryotic genome regulate gene expression. These non-coding regulatory regions, including promoters and enhancers, are controlled by the binding of multiple transcription factors which act together to regulate gene transcription. The number of potential transcription factor combinations regulating any gene presents a massive experimental challenge. One well-known transcription factor, p53, activates multiple transcription pathways involved in tumor suppression, primarily through engagement with enhancers. p53 is one member of a paralogous transcription factor family, which includes the factor p63. Whereas p53 is involved in tumor suppression, p63 is a transcription factor responsible for maintaining epithelial cell …
Rna Secondary Structure Of 3’Utr Regulates Translation Control, M. Grace Hren
Rna Secondary Structure Of 3’Utr Regulates Translation Control, M. Grace Hren
Biological Sciences
According to the central dogma of biology, DNA is transcribed into mRNA. This mRNA is then translated into a protein. Translation of mRNA into protein is extremely precise, and as such is controlled by many different factors, both spatially and temporally. This phenomenon is known as translation control. Many times, this regulation is influenced by secondary structures, often in the form of stem loops on the mRNA. These secondary structures found on mRNA, specifically in the 3’Untranslated Region (3’UTR) of mRNA, can influence cellular gene expression. These genes can be upregulated or down regulated, depending on stem loop function. When …
Pre-Administration Of Medium Chain Triglycerides In Vivo Can Attenuate Or Block The Effects Of Recurrent Hypoglycemia, Dhanisha Nandigama
Pre-Administration Of Medium Chain Triglycerides In Vivo Can Attenuate Or Block The Effects Of Recurrent Hypoglycemia, Dhanisha Nandigama
Biological Sciences
Hypoglycemia is a state of abnormally low blood glucose. Many patients who use insulin, primarily for the treatment of diabetes, experience multiple bouts of hypoglycemia, termed recurrent hypoglycemia (RH). Because RH impairs cognitive function and ability to appropriately respond to a subsequent episode of hypoglycemia, it is critical to develop treatments. One approach, which we have taken here, is to attempt to preserve neuronal fuel supply during a hypoglycemic episode. Medium-chain triglycerides are medium-chain fatty acid (MCT) esters of glycerol that can provide an alternative fuel source to the brain via ketones; the hippocampus is known to express transporters for …
Investigating The Effects Of Intrahippocampal Glucose Administration On Spatial Working Memory In Rats, Jeremy Carter
Investigating The Effects Of Intrahippocampal Glucose Administration On Spatial Working Memory In Rats, Jeremy Carter
Biological Sciences
Insulin is a peptide hormone released by beta pancreatic cells . Insulin’s best-known function is to regulate absorption of glucose into peripheral tissue: this occurs via activation of the phosphoinositide 3-kinase (PI3K) signaling cascade and subsequent translocation of glucose transporter 4 (GLUT4) to the cell surface. This canonical peripheral insulin signaling pathway appears to exist in essentially identical form within the central nervous system (CNS), so that insulin promotes entry of glucose into neural cells and subsequent increased metabolism. In order to maintain proper function, insulin-responsive hippocampal neurons and glia require glucose metabolism; a catabolic energy-yielding process that requires insulin …
The Efficacy Of Ventral Pallidum- Deep Brain Stimulation In Rat Models Of Epilepsy, Fu Yee Chua
The Efficacy Of Ventral Pallidum- Deep Brain Stimulation In Rat Models Of Epilepsy, Fu Yee Chua
Biological Sciences
Antiepileptic drugs have been a primary option for patients with epilepsy worldwide, however, about one-third of patients do not respond to pharmacotherapy. For these individuals, resective surgery can be performed but seizures are still reported in some cases. With that in mind, neuromodulation or deep brain stimulation (DBS) is a plausible alternative to provide seizure freedom for refractory individuals. Vagus nerve stimulation (VNS), anterior thalamus DBS and responsive neurostimulation (RNS) are FDA approved as neuromodulatory approaches for epilepsy. They reduce and delay seizures but do not prevent or abolish seizures. In the previous study, the Shin lab showed that DBS …
Current And Future Environmental And Human Health Impacts Associated With Biofuel/Biofuel Feedstock Production, Eun Kyung Lee
Current And Future Environmental And Human Health Impacts Associated With Biofuel/Biofuel Feedstock Production, Eun Kyung Lee
Legacy Theses & Dissertations (2009 - 2024)
Background: The demand for biobased products, such as food, fuel, and chemicals, has been continuously increasing. Meanwhile, agricultural production, serving as the primary stage of biobased products, is one of the largest contributors to greenhouse gas (GHG) emissions and nutrient releases. Although assessing spatially and temporally explicit environmental releases and impacts are required to inform a sustainable trajectory for agricultural production, such analyses are largely lacking due to data unavailability and feasibility of data analysis. Moreover, our current understanding of health impacts associated with biofuel production are lacking due to the limited assessment of health impacts resulted from biofuels’ entire …
Premature Rho-Dependent Transcription Termination In Escherichia Coli : Link To Translation And Gene Regulation, Gabriele Baniulyte
Premature Rho-Dependent Transcription Termination In Escherichia Coli : Link To Translation And Gene Regulation, Gabriele Baniulyte
Legacy Theses & Dissertations (2009 - 2024)
Transcription termination factor Rho is an essential protein in Escherichia coli and related bacteria. The primary function of Rho is to clear unproductive RNA polymerases from the DNA template to minimize negative effects associated with uncontrolled transcription. Although most of the Rho termination events are constitutive, premature Rho-mediated termination was observed at 3% of all affected transcripts indicating active regulation of Rho activity. In this work, we investigated the regulatory mechanism behind premature Rho-dependent transcription termination in two unrelated genes: suhB and topAI. We show that in both cases transcription is terminated inside the coding gene as a consequence of …
Evaluation Of Fingerprint Content For Forensic Crime Scene Analysis And Drug Metabolite Detection, Erica Kathryn Brunelle
Evaluation Of Fingerprint Content For Forensic Crime Scene Analysis And Drug Metabolite Detection, Erica Kathryn Brunelle
Legacy Theses & Dissertations (2009 - 2024)
With respect to criminal investigations, one key piece of evidence that often gets overlooked are fingerprints. For years, fingerprint samples have been believed to be useful only for matching purposes using their unique ridges, shapes, and sizes. With the rapid growth of forensic science, it has become evident that the development of fingerprint analysis has been stagnant. The traditional approach has been advantageous for the identification of many individuals; however, many fingerprint samples have been labeled “unusable” due to smudging, smearing, or any one of a myriad of reasons that could cause inconclusive matches. These samples can, however, still be …
Tribute From The Underworld : The Historical Ecology Of The Maya Postclassic Fish Trade With Isotopic Analysis Of Otoliths From MayapáN And Caye Coco, Jeffrey Michael Bryant
Tribute From The Underworld : The Historical Ecology Of The Maya Postclassic Fish Trade With Isotopic Analysis Of Otoliths From MayapáN And Caye Coco, Jeffrey Michael Bryant
Legacy Theses & Dissertations (2009 - 2024)
This dissertation investigates the Maya fish trade through the extensive analysis of fish otoliths (ear stones), from the Postclassic sites of Mayapán, and Caye Coco, and provides an initial foundation for the development of a historical ecology program. Through osteometry, thin-section microscopy of growth rings, and microscale stable isotope analysis (δC13 and δO18), a spectrum of data is produced to characterize the Postclassic fish trade. These data are used to illuminate themes of the seasonality of the fish harvest, diet, biodiversity, fish population demography, environmental change, sustainability, and resilience. The timing of a seasonal intensification of the harvest is viewed …
Contrasting Roles Rna Binding Proteins G3bp1 And Hur Influence Zika Virus And A Proposed Mechanism By Which Zika Virus Induces Neurological Complications, Gaston Bonenfant
Contrasting Roles Rna Binding Proteins G3bp1 And Hur Influence Zika Virus And A Proposed Mechanism By Which Zika Virus Induces Neurological Complications, Gaston Bonenfant
Legacy Theses & Dissertations (2009 - 2024)
Globalization and climate change have contributed to the rampant spread of mosquitos from tropical and subtropical climates into more moderate climates, and thus also the spread of a number of vector-borne viruses. As of 2016, the World Health Organization (WHO) estimates that of all human infections world-wide, 16% result from vectors such as flies, ticks, and mosquitos. The spread of such viruses has encouraged expedient evolutionary pressures resulting in more pathogenic viruses that continually pose a serious threat to public health. First discovered in 1947, Zika virus (ZIKV) has only recently presented as a detriment to public health. The importance …
Phenotypic And Genetic Variation Of The Brazilian Malaria Vector Nyssorhynchus Darlingi At Regional And Local Scales, Virginia Mildred Chu
Phenotypic And Genetic Variation Of The Brazilian Malaria Vector Nyssorhynchus Darlingi At Regional And Local Scales, Virginia Mildred Chu
Legacy Theses & Dissertations (2009 - 2024)
There have been major successes in the fight to eliminate malaria in the Americas, with 11
Of Donuts And Promo : In Silico Approaches To Identification Of Transcriptional Regulators Of Salivary Acinar Differentiation, Connor Cillian Duffy
Of Donuts And Promo : In Silico Approaches To Identification Of Transcriptional Regulators Of Salivary Acinar Differentiation, Connor Cillian Duffy
Legacy Theses & Dissertations (2009 - 2024)
The salivary gland is an organ often taken for granted by most people. However, its proper function is essential for several everyday activities, such as speaking, swallowing, and tasting. As such, impaired salivary gland function, such as that caused by Sjögren’s Syndrome or radiotherapy for head and neck cancers, can lead to a significantly reduced quality of life. The cells that produce saliva in salivary glands are known as acinar cells, which arise from proacinar cells generated during embryonic development. As such, in studying the promoter regions of proacinar and acinar genes, it may be possible to identify common transcription …
Saliva As A Diagnostic Biological Fluid And The Human Salivary Proteome, Jessica Ghassan Emsies
Saliva As A Diagnostic Biological Fluid And The Human Salivary Proteome, Jessica Ghassan Emsies
Legacy Theses & Dissertations (2009 - 2024)
Saliva is a unique biologic fluid that contains a varying spectrum of proteins, nucleic acids, electrolytes, and hormones.31 It is an exocrine secretion of the salivary glands which is hypotonic in nature with a pH of 7.2-7.4.31 Saliva plays an important role in the oral cavity.33 It lubricates, hydrates, and bathes the oral cavity, therefore, aiding speech and mastication.33 Saliva forms a barrier on the teeth, protects against demineralization, and aids in remineralization.33 Saliva is required for chewing and food bolus preparation, it contains enzymes necessary for digestion, and mediates the sense of taste.33 It also helps wound healing and …
The Effect Of Maternal Dietary Habits During Pregnancy On Neonate Leptin Methylation Patterns And Gestational Age, Sean Fitzpatrick
The Effect Of Maternal Dietary Habits During Pregnancy On Neonate Leptin Methylation Patterns And Gestational Age, Sean Fitzpatrick
Legacy Theses & Dissertations (2009 - 2024)
The health of a newborn baby is inextricably linked to the health status of its mother and in turn the mother’s diet during pregnancy. Leptin (LEP) is an adipokine hormone involved in metabolism regulation and has been linked fetal development through the hypothalamic-pituitary-adrenal axis (HPA). Prior work suggests that gestational epigenetic alterations the LEP gene may be sensitive to adverse exposures during pregnancy, which in turn could explain variation in neonate outcomes. However, no prior work has examined this possibility explicitly. The objective of this study was to investigate the association between dietary patterns of mothers during pregnancy and their …
Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra
Defining And Harnessing Nature's Selection Of Geranylation In Rna Modification, Phensinee Haruehanroengra
Legacy Theses & Dissertations (2009 - 2024)
Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. Geranylated-2-thiouridine is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, namely E. coli, E. aerogenes, P. aeruginosa and S. typhimurium by Liu group. It has been found as a post-transcription modification on the wobble position of anticodon of tRNAs specific for glutamic acid, glutamine and lysine. Geranylated-tRNA was shown to correct the frameshifting during the translation of E. coli. However, the reason of the existing of the modification is still largely unclear. To understand why nature incorporates such a hydrophobic group in …
The Role Of Rock Signaling On Salivary Gland Organoid Formation, Matthew Koslow
The Role Of Rock Signaling On Salivary Gland Organoid Formation, Matthew Koslow
Legacy Theses & Dissertations (2009 - 2024)
Salivary glands are crucial organs that are responsible for secreting saliva which is important for the breakdown of carbohydrates, providing lubrication of the mouth, and maintenance of oral health. Patients diagnosed with Sjögren's Syndrome or receiving treatment for head and neck cancer, can permanently lose salivary gland function, which is referred to as salivary hypofunction. As a result, these patients develop Xerostomia, or the feeling of dry mouth, and suffer from an overall decreased quality of life. To combat the negative effects of salivary hypofunction, stem cell therapy is an attractive option, as implantation of specific cell populations can rescue …
The Role Of Progesterone Receptor In The Developing Medial Preoptic Nucleus, Diana Lalitsasivimol
The Role Of Progesterone Receptor In The Developing Medial Preoptic Nucleus, Diana Lalitsasivimol
Legacy Theses & Dissertations (2009 - 2024)
Numerous neurodevelopmental and neuropsychiatric diseases have a distinct sex bias in
Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy
Post-Translational Modifications And Functional Studies Of Dksa In Escherichia Coli, Andrew Charles Isidoridy
Legacy Theses & Dissertations (2009 - 2024)
DksA is a bacterial gene regulator that functions synergistically with the stress alarmone ppGpp to mediate the stringent response. DksA also functions independently of ppGpp to regulate transcription of a number of genes. DksA function is dependent on its binding affinity to RNA polymerase and requires specific interactions between RNAP and catalytic amino acids located on the coiled coil tip, D74 and A76. While much of the previous work on DksA has focused on understanding the mechanisms of action and the numerous gene targets for transcriptional regulation, little is known about the mechanisms by which DksA expression and function may …
Epitranscriptomic Writer Systems And Codon Bias Regulate The Response To Environmental Stress, Andrea Leonardi
Epitranscriptomic Writer Systems And Codon Bias Regulate The Response To Environmental Stress, Andrea Leonardi
Legacy Theses & Dissertations (2009 - 2024)
Epitranscriptomic marks in the form of enzyme-catalyzed modifications to RNA nucleosides can be important regulators of translation and play integral roles in the response to stress. Dynamic changes in tRNA modification status can regulate the translation of stress response proteins whose transcripts have distinct codon biases. The epitranscriptomic writer Alkylation repair homolog 8 (ALKBH8) plays a crucial part in the translation of codon biased transcripts, as it regulates stop codon recoding, which is a specialized form of translation used to generate selenoproteins. ALKBH8 modifies the wobble uridine of selenocysteine tRNA (tRNASec) to promote the decoding of an internal UGA codon …
Environmental Influences On Rates Of Osteo- And Rheumatoid Arthritis, Azad Abdulrahman Mohammed
Environmental Influences On Rates Of Osteo- And Rheumatoid Arthritis, Azad Abdulrahman Mohammed
Legacy Theses & Dissertations (2009 - 2024)
Abstract
The Role Of Progesterone Receptor In The Development Of The Mesocortical Serotonergic Pathway, Allyssa Phillips
The Role Of Progesterone Receptor In The Development Of The Mesocortical Serotonergic Pathway, Allyssa Phillips
Legacy Theses & Dissertations (2009 - 2024)
The mesocortical serotonergic pathway, consisting of serotonergic fibers projecting from the dorsal raphe nucleus (DRN) to the prefrontal cortex (PFC), regulates higher order executive functions and complex cognitive behaviors. Disruptions in this pathway lead to dysfunction in behavior and have been linked to several clinical disorders, including anxiety and ADHD. While this pathway continues to change throughout the lifespan, it is during early development that this pathway undergoes a rapid period of maturation, with the greatest rate of fiber innervation and synaptogenesis occurring in the mesocortical serotonergic pathway at this time. The development of a properly functioning circuit is directed …
Characterization Of A Novel, Stress-Responsive Sexually Dimorphic Corticotropin-Releasing Factor Receptor 1 (Crfr1) Nucleus In The Rostral Anteroventral Periventricular Nucleus Of The Mouse, Zachary Julius Rosinger
Characterization Of A Novel, Stress-Responsive Sexually Dimorphic Corticotropin-Releasing Factor Receptor 1 (Crfr1) Nucleus In The Rostral Anteroventral Periventricular Nucleus Of The Mouse, Zachary Julius Rosinger
Legacy Theses & Dissertations (2009 - 2024)
Within the United States, women are at double the risk of men to develop a stress-related mood disorder (e.g., anxiety or depression) during their reproductive years (Kornstein et al., 2000; Kessler et al., 2005). Many factors contribute to the potential sex difference in such disorders, including gonadal hormones (hypothalamic-pituitary-gonadal axis; HPG) and how they interact with the stress response system, or hypothalamic-pituitary-adrenal (HPA) axis. Corticotropin-releasing factor (CRF) signals through binding the GS-coupled receptor, CRF receptor 1 (CRFR1), and activity between CRF/CRFR1 regulates the hormonal and behavioral stress response (Chen et al., 1993; Bale and Vale, 2004; Heinrichs et al., 1995; …
The Effect Of Anthropogenic Environmental Modifications On Malaria Vectors In Amazonian Peru And Brazil, Catharine Prussing
The Effect Of Anthropogenic Environmental Modifications On Malaria Vectors In Amazonian Peru And Brazil, Catharine Prussing
Legacy Theses & Dissertations (2009 - 2024)
Malaria is the most deadly vector borne disease, causing substantial morbidity and hundreds of thousands of deaths worldwide each year. In the Americas, the incidence of malaria has increased steadily since 2014. The factors driving continued malaria transmission are complex and highly variable across endemic areas. These factors include inadequate access and financial commitment to prevention, diagnosis, and treatment, and a failure to target interventions to heterogeneous malaria transmission patterns and vector populations. Nyssorhynchus darlingi (formerly Anopheles darlingi), the predominant malaria vector in Latin America, is known for behavioral, phenotypic, and genetic variability across its range, which allow it to …
Developmental Changes In The Activation And Structure Of The Contextual Fear Neural Circuit From Infancy To Adulthood, Anthony John Santarelli
Developmental Changes In The Activation And Structure Of The Contextual Fear Neural Circuit From Infancy To Adulthood, Anthony John Santarelli
Legacy Theses & Dissertations (2009 - 2024)
The contextual fear circuit, centered on the basolateral nucleus of the amygdala (BLA), is comprised of projections from the hippocampal formation and prefrontal cortex, and mediates an animals ability to learn and predict associations between the environment and biologically relevant stimuli. While the function and structure of this circuit has been well characterized in adult species, relatively little is known about its development as an animal transitions from infancy to adulthood. Recent evidence has begun to suggest that infants, juveniles, and adolescents may show remarkable heterogeneity in the behavioral, activational, and structural properties of the circuit. In this thesis, I …
Inteins From Pathogenic Microbes As Regulatory Elements And Potential Drug Targets, Cathleen Maria Schiraldi
Inteins From Pathogenic Microbes As Regulatory Elements And Potential Drug Targets, Cathleen Maria Schiraldi
Legacy Theses & Dissertations (2009 - 2024)
Inteins are self-splicing elements that orchestrate the autocatalytic process of protein splicing, during which the intein excises itself from a host polypeptide. This multistep reaction involves a series of coordinated nucleophilic attacks and peptide bond rearrangements that remove the intein and reassemble the flanking halves, called exteins, to form the mature host protein. Some inteins are also mobile elements, and can spread to the same or ectopic sites using an internal homing endonuclease domain.
Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen
Significance Of Rna 2'-5' Linkage And Metal-Ion Mediated Base Pairs, Fusheng Shen
Legacy Theses & Dissertations (2009 - 2024)
It has been known that the template-directed RNA chemical replication reaction produces mixture of backbones containing both 3’-5’ and 2’-5’ linkages. This backbone heterogeneity has been a significant problem in studying the emergence of RNA World from the prebiotic chemistry. However, very recently, it is reported that FMN binding aptamer and a hammerhead ribozyme are still able to retain considerable functions in the presence of certain 2’-5’ linkages, indicating that RNA backbones may be quite flexible and this backbone heterogeneity problem may not be as severe as originally thought. This finding also brings two related important questions: First, how does …
Examining The Mechanisms Of Nucleic Acid Structural Rearrangements Using Nanospray Ionization Mass Spectrometry, Botros Toro
Examining The Mechanisms Of Nucleic Acid Structural Rearrangements Using Nanospray Ionization Mass Spectrometry, Botros Toro
Legacy Theses & Dissertations (2009 - 2024)
RNA’s diverse gene regulatory functions are tied to its ability to adopt and rearrange between an ensemble of three-dimensional structures. This concept is illustrated by the process of genome dimerization in HIV-1 and other retroviruses, which is mediated by the dimerization initiation site (DIS) of viral RNA. This essential stem-loop domain establishes a metastable kissing complex (KC) intermediate that seeds the structural rearrangements necessary to stabilize genome dimerization. Most approaches applied to study RNA structure provide us with a snapshot of RNA at equilibrium, leaving key details on dynamics concealed. This thesis explored the merits of nanospray ionization mass spectrometry …
Development Of A Neutropenic Murine Model For Invasive Candida Auris Infection, Steven Torres
Development Of A Neutropenic Murine Model For Invasive Candida Auris Infection, Steven Torres
Legacy Theses & Dissertations (2009 - 2024)
In less than a decade, the emerging fungal pathogen Candida auris has become a major public health threat due to its multidrug resistant (MDR) phenotype, high transmissibility, and high mortality rates that range between 30%-60%. Unlike other Candida species, C. auris has acquired high levels of resistance to an already limited arsenal of antifungals. As an emerging pathogen, there are currently a limited number of documented murine models of C. auris infection. These animal models using a range of inoculums from 105 –108 cells per mouse, and the environmental and occupational exposure of working with these models has not been …
Accumulation And Spatial Distribution Of Lead And Other Trace Elements In Keratinized Tissues : Investigations Based On Analytical Atomic Spectrometry, Mina W. Tehrani
Accumulation And Spatial Distribution Of Lead And Other Trace Elements In Keratinized Tissues : Investigations Based On Analytical Atomic Spectrometry, Mina W. Tehrani
Legacy Theses & Dissertations (2009 - 2024)
Human biomonitoring for toxic metals such as lead (Pb) provides information about absorbed dose from all exposure routes, and is critical for identifying exposed individuals and assessing health risks. Blood Pb and bone Pb are the primary validated biomarkers for assessing short-term and historical Pb exposures, respectively, while non-traditional matrices, including keratinized tissues, can provide complementary exposure information. Hard keratinized tissues – including hair, nails, hooves, and horns – grow incrementally, potentially preserving chemical exposure histories over a span of days to years. Analytical limitations and poor interlaboratory reproducibility, however, have led to debate around the use of human nails …