Biology Commons^™

T Cell Immunity In Pancreatic Cancer Is Undermined By Dendritic Cell Dysfunction, Samarth Hegde

Arts & Sciences Graduate Student Theses and Dissertations

Pancreatic cancer carries a dismal prognosis, and desperately needs viable therapeutic interventions beyond chemo-radiation. T cell-dependent immunotherapies have shown great promise in several tumor types, but have not been effective for the vast majority of pancreatic cancer patients. This is, in part, due to our limited understanding of how antigenicity of pancreatic lesions is recognized, and how adaptive immunity is overcome in this disease. We sought to study tumor-immune interactions and identify mechanisms for this immune-failure using several spontaneous and unperturbed mouse models of pancreatic adenocarcinoma. We found that early pancreatic lesions fail to elicit tumor-limiting CD4+ TH1 and CD8+ …

Elucidating Enhancer Function In Epidermal Development And Filaggrin Loss-Of-Function Variants In African American Atopic Dermatitis, Mary Elizabeth Mathyer

Arts & Sciences Graduate Student Theses and Dissertations

The epidermis is the outermost tissue of the skin and provides the body’s first line of defense against external assaults. The epidermis is primarily composed of keratinocytes that terminally differentiate and rise apically toward the surface to form the semipermeable barrier of the skin. A hallmark of keratinocyte terminal differentiation is the expression of genes from the Epidermal Differentiation Complex (EDC) locus. Many of the EDC protein products contribute to the structural integrity of the skin barrier, evidenced by several gene knockouts such as loricrin, and even genetic variation within gene coding sequences, that modulate the integrity of the skin …

Transcriptional Regulation Of Adipose Tissue Development By Pexrap And Med19, John Dean

Arts & Sciences Graduate Student Theses and Dissertations

Targeting adipose tissue function to decrease adiposity and improve insulin sensitivity could treat obesity and diabetes. How the nuclear receptor PPARγ regulates the development of two functionally distinct types of adipose tissue, brown and white fat (BAT and WAT), as well as the browning of white fat, remains unclear. Our previous studies suggest that PexRAP, a peroxisomal lipid synthetic enzyme, regulates PPARγ signaling and white adipogenesis.Here, we show that PexRAP is an inhibitor of brown adipocyte gene expression. PexRAP inactivation promoted adipocyte browning, increased energy expenditure, and decreased adiposity. Identification of PexRAP-interacting proteins suggests that PexRAP function extends beyond its …

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …

Physiologic And Pathologic Profiling Of Clonal Variations, Wing Hing Wong

Arts & Sciences Graduate Student Theses and Dissertations

This thesis sought to provide a better understanding of clonality in various malignant and non-malignant settings using a variety of genomic analytical tools. Clonality is pre-defined as the presence of a mixed population of cells in which each sub-population has distinct somatic mutation profile. It is a common feature in cancers where subpopulations of cells arise as a result of independent, yet continual acquisition of somatic mutations. The clonal architecture of cancers can be used as a diagnostic and prognostic biomarker as well as to monitor disease progression or resolution. Besides cancer, clonal variability and expansion is also implicated in …

Generation And Utilization Of Diverse Memory B Cells After Flavivirus Challenges, Rachel Wong

Arts & Sciences Graduate Student Theses and Dissertations

Over the course of an effective immune response to an infection, two distinct B cell populations are generated to provide protection against reinfection, long-lived plasma cells (LLPCs) and memory B cells (MBCs). LLPCs and MBCs originate from germinal center (GC) B cells that have undergone B cell receptor (BCR) affinity maturation through iterative rounds of somatic hypermutation, proliferation, and selection. Thus, LLPCs and MBCs can bind to their antigen with higher affinity than their naïve B cell precursors. LLPCs constitutively secrete antibodies and can provide sterilizing immunity that pre-exists subsequent infections. MBCs, on the other hand, are quiescent and provide …

Trade-Offs Between Survival And Reproduction In Starvation-Selected Drosophila Melanogaster, Tammara Beeghly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Evolutionary outcomes are demonstrated by traits that affect an organism’s schedule of reproduction and survival. These life history traits are reflected in an organism’s physiology, development and behavior. Environmental changes, such as availability of nutritional resources, can profoundly affect evolutionary outcomes of individuals and populations. When shortages arise, there will be trade-offs in the allocation of resources, where one trait prevails at the expense of another.

In the laboratory, we can mimic conditions in nature and study the specific effects of the conditions that we re-create. In our case, over 100 generations of Drosophila melanogaster have been selected for starvation …

The Effect Of Pleistocene Glacial - Interglacial Cycles On Patterns Of Genetic Diversity And Differentiation Of Populations Of Leptodactylus Albilabris (White-Lipped Frog) In The Puerto Rican Bank, Andre Nguyen

UNLV Theses, Dissertations, Professional Papers, and Capstones

The historical distributional shifts of various species have been attributed to the glacial-interglacial cycles of the Pleistocene Epoch (2.6 mya – 10,000 ya). Sea level changes caused by Pleistocene glacial-interglacial cycles impacted the total area of landmasses, particularly in island systems. Cooler, glacial periods increased emergent (subaerial) island area via lower sea levels. Adjacent islands may have become connected through emergent land bridges, resulting in a larger subaerial landmass. Warmer interglacial periods led to higher sea levels, which in turn reduced island area, and in some cases, submerged land bridges, fragmenting larger islands into separate, smaller units. The Puerto Rican …

Restructuring Of The Axon Initial Segment In Mouse Models Of Neurodevelopmental Disorders, Rachel Ali Rodriguez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Neurodevelopmental disorders (NDDs) affect more than 36% of children in countries with low- and middle- incomes (Boivin, 2015; McCoy, 2016). Interestingly, these heterogeneous disorders share a high incidence of epileptic seizures, suggesting a shared pathology. Seizures result when neuronal firing activity becomes disturbed and neurons fire excessively or in unregulated patterns. A key site in the control of neuronal firing patterns is the axon initial segment (AIS), where the local density of proteins and the morphology of the AIS in part determine the firing of neurons. We hypothesized that a disruption in the morphology and/or composition of the AIS can …

Mojave Desert Plant Community Long-Term Response To Disturbance, Dominic M. Gentilcore

UNLV Theses, Dissertations, Professional Papers, and Capstones

All vegetation communities have been shaped by disturbances. This dissertation consists of three separate chapters: Blackbrush (Coleogyne ramosissima) natural regeneration in the Great Basin-Mojave Desert Transition Zone on two fires, Long-term Response to Fire in Eastern Mojave Desert semi-arid shrubland communities, and an Annotated Checklist of Gold Butte National Monument in the Mojave-Colorado Plateau Transition Zone. The section on blackbrush natural regeneration was a long-term dataset from two fires in Basin and Range National Monument that burned in 2008 with monitoring events in 2009, 2010, 2011, 2018 and 2019. The monitoring documented some of the strongest post-fire regeneration for the …

An Evolving Epigenome That Determines Tissue And Cell Specificity, Renee Louise Sears

Arts & Sciences Graduate Student Theses and Dissertations

Understanding the mechanisms driving phenotypic variation is a major goal of biology that unifies classical genetics with the emerging fields of genomics and epigenomics. Human and mouse share over 90% of genes and global tissue-specific patterns of expression are maintained between the species. Thus, it is hypothesized that gene expression is influenced through distinctive regulation among species in order to account for the unmistakable phenotypic divergence. DNA methylation, histone modifications, open chromatin patterns, transcription factor binding, and other epigenetic factors are all associated with shaping, maintaining, and repressing regulatory regions which in turn coordinate gene expression. It is vital to …

Activation And Regulation Of The Alkbh3-Ascc Alkylation Repair Pathway, Josh Brickner

Arts & Sciences Graduate Student Theses and Dissertations

DNA repair is essential to prevent the cytotoxic or mutagenic effects of various types of DNA lesions. These lesions are sensed by distinct pathways to recruit repair factors specific to type of damage. In particular, the ALKBH family of proteins recognizes and repairs specific alkylated lesions, including 1-methyladenine (m1A) and 3-methylcytosine (m3C). A major outstanding question in the field is how the AlkB homologue ALKBH3 and its associated protein partners are recruited to sites of alkylation damage and how this repair activity is regulated. Understanding the upstream signaling events that mediate recognition and repair of DNA alkylation damage is particularly …

The Transcription Factor Bhlhe40 Regulates Tissue-Resident Macrophages And Type 2 Immunity, Nicholas N. Jarjour

Arts & Sciences Graduate Student Theses and Dissertations

Transcriptional control of gene expression is essential for life, tailoring protein production to development and environment to maintain organismal homeostasis. A limited set of proteins termed transcription factors are critical to this process. As our understanding of these central regulators has improved, new aspects of cell and organismal biology have been revealed. Herein, we demonstrate the importance of the transcription factor Bhlhe40 to tissue-resident macrophages, T helper type 2 cells, and type 2 immune responses, revealing novel transcriptional control of macrophages and unexpected cytokine regulation of helminth infection. We find that Bhlhe40 is cell-intrinsically required for normal proliferation of large …

Phylogenetic And Genomic Characterization Of The Host-Pathogen Arms Race Between Bacterial Pathogens And Gossypium Hirsutum, Anne Zimmerman Phillips

Arts & Sciences Graduate Student Theses and Dissertations

Hosts and pathogens are eternally intertwined in an evolutionary arms race. When a pathogen causes a disease outbreak, scientists must identify resistance strategies that can durably tilt the arms race in favor of the host. This requires a deep understanding of both the genetic and environmental contexts in which the outbreak occurs. In this thesis I investigate the bacterial pathogens Xanthomonas citri pv. malvacearum (Xcm) and Pseudomonas syringae that caused disease outbreaks on Gossypium hirsutum from 2011-2017. I use pathogen genomics and host transcriptomics to develop hypotheses for how these pathogens emerged and how they cause disease. Phylogenetics and virulence …

The Biomedical Application Of Chimeric Antigen Receptor T Cell Therapy, Jessica Devenport

Arts & Sciences Graduate Student Theses and Dissertations

No abstract provided.

Quantification Of Neuronal Specific Responses To Depletion Of The Nascent Polypeptide-Associated Complex In Caenorhabditis Elegans, Harrison Hall

Senior Honors Projects, 2010-2019

Cells experiencing misfolded protein stress can become debilitated and die, consistent with this stress being linked to numerous diseases. When misfolded proteins accumulate in the endoplasmic reticulum (ER), the unfolded protein response (UPR) initiates mechanisms that resolve this stress or trigger apoptosis, dependent on the severity and/or duration of the stress. The nascent polypeptide-associated complex (NAC) is a heterodimeric chaperone that mediates proper protein folding and localization during translation; depletion of the NAC promotes misfolded protein stress in the ER, resulting in the initiation of the UPR in affected cells. The relationship between the NAC and the UPR is not …

Investigating The Relationship Between Hormone Receptors Dax-1 And Estrogen Receptor Within Prostate Cancer Cell Lines, Meghana G. Vijayraghavan

Master's Theses

Prostate cancer (PCa) is estimated to be the second leading cause of cancer-related deaths among men in the United States in 2019. While most prostate tumors rely on androgens for growth signaling, there are subsets of tumors that become androgen-resistant, therefore resisting conventional androgen-depravation therapy. Consequently, research has focused on targeting different hormone receptors for novel therapeutics. One such receptor is Dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1 (DAX-1). DAX-1 is known to interact with other hormone receptors, such as androgen receptor (AR) and estrogen receptors (ERs) to suppress the proliferative effects …

Bio Buzz Newsletter, Issue 18, December 2019, Denison Biology Department

Biology Buzz Newsletter

No abstract provided.

Bio Buzz Newsletter, Issue 17, June 2019, Department Of Biology

Biology Buzz Newsletter

No abstract provided.

Fish Assemblages Of The Withlacoochee River Basin In South Georgia, Usa, Matthew J. Cannister, David L. Bechler

Georgia Journal of Science

An ichthyofauna review of literature prior to 2008 on the Withlacoochee River basin in south-central Georgia, USA, indicated that the fish fauna was underrepresented compared to other rivers, such as the Suwannee River basin in Florida of which the Withlacoochee River is a tributary. A survey would provide the state of Georgia potentially valuable additional information on the fish fauna within the basin. A 45-site survey within the eastern portion of the Withlacoochee River basin was conducted from 2008 to 2010 employing seines, gill nets, fish traps, trotlines, and creel surveys. Surveys yielded 51 fish species of which three, the …

Overcompensation In Aedes Mosquitoes Populations: Field Tests On Likelihood And An Agent-Based Model To Investigate The Influence Of Cohort Structure, Katherine G. Evans

Theses and Dissertations

The number of individuals in a competitive environment can affect the growth rate, survival, size, and fecundity of those individuals, which is known as density-dependent effects. Overcompensation may occur if few juveniles survive to adulthood in a high-density environment. Overcompensation arises when density dependent survival interacts with extrinsic sources of mortality, such that more juveniles survive to adulthood than if no extrinsic mortality had occurred.

I tested the hypothesis that density dependent effects are common and strong in the field for three mosquito species: Aedes aegypti, Aedes albopictus, and Aedes triseriatus. I surveyed naturally occurring densities in novel and established …

The Biosorption Of Lead From Aqueous Solutions By A Wood-Immobilized Fungal Biosorbent, Zomesh A N Maini, Niña Therese B. Flores, Enrico P. Muñoz

Biology Faculty Publications

Lead [Pb(II)] biosorption capacities of immobilized Talaromyces macrosporus on Moringa oleifera L. wood were compared against pure fungal and pure M. oleifera biomass. A Pb(II) contact test of 1000 ug/mL show similar Pb(II) removal of non-immobilized fungal biomass (F) and powdered wood colonized with fungi (WP+F), with WP+F producing more biomass. Powdered sorbents had higher Pb(II) uptake compared to whole sorbents analyzed through ICP-AES, possibly due to increased surface area for Pb(II) binding. FTIR analysis of the F, WP, and WP+F identified hydroxyl, amino, carbonyl, and sulfhydryl functional groups which constitute probable Pb(II)-affinitive binding sites. The biosorbents tested in a …

Biological And Psychological Implications Of Mindfulness Meditation For College Students, Kelsey Madison Dietrich

Honors Projects

The purpose of this capstone project was threefold: investigate the psychological implications of mindfulness meditation for college students enrolled in a semester-long course introducing these practices, investigate the biological implications of mindfulness meditation for these students, and create the Peer Education “Mindfulness” presentation for the Wellness Connection to introduce mindfulness meditation methods to a greater quantity of college students. The following paper describes the two components of this capstone project that examine the implications of mindfulness meditation opportunities available for college students specifically at Bowling Green State University in Bowling Green, Ohio.

Undergraduates And Stress, Mahra Crone

Honors Projects

America is facing a serious mental health crisis, which may be an effect of increased chronic stress. Students, in particular, are vulnerable to this hazard as most face a moderate to extreme amount of stress. The programs which colleges and universities have put into place are outdated. Ineffective treatment of mental health crises leads to disastrous consequences. The present study analyzed the effects of major and grade level on stress level and sources of stress for undergraduate universities at both a large, public university and a small, private college. The author found that a student’s grade level and choice of …

The 14-3-3 (Ywha) Proteins In Signalling And Development Of The Fruit Fly, Drosophila Melanogaster, Santanu De

Biology Faculty Articles

The 14-3-3 (YWHA or Tyrosine 3-Monooxygenase/Tryptophan 5-Monooxygenase Activation proteins) are a family of highly conserved, homologous proteins critical to diverse cellular events including cell cycle, signal transduction and embryonic development. Various species-specific isoforms of 14-3-3 exist, encoded by separate genes. They are expressed in a wide variety of organisms ranging from plants to animals, including the fruit fly or Drosophila melanogaster. Drosophila is one of the most universally accepted model systems to study complex cellular mechanisms of signalling and development. However, regulation of these processes in fruit flies by the 14-3-3 proteins have not been entirely understood. This mini …

Assessment Of Cytotoxic Activity Of Five Common Philippine Medicinal Plants Using Brine Shrimp Lethality Assay, Lloyd O. Balinado, Merab A. Chan

Biology Faculty Publications

A wide variety of plants in the Philippines are used to address several medical ailments; however, many of which have not yet undergone thorough pharmacological studies. The problem on the possible side effects caused by these medicinal preparations has, therefore, increased the interest in validating their safety for human use. The present study was conducted to determine the cytotoxicity of five common local medicinal plants. Annona muricata L., Cymbopogon citratus DC., Graptophyllum pictum (L.) Griff, Jatropha curcas L., and Piper betle L. were selected and subjected to crude aqueous leaf extraction. Extracts were then investigated for cytotoxicity potential using brine …

Design Of Reinforced Concrete Deep Beams Using Particle Swarm Optimization Technique, Qais F. Hasan, Dler A. Al-Mamany, Omer K. Fayadh

Karbala International Journal of Modern Science

Researches available in literature interrelating neural networks to civil engineering design problems, especially for beep beams, are very rare. Therefore, an optimization algorithm is developed and verified in this study and coded using MATLAB functions to determine the optimum cost design of reinforced concrete deep beams. ACI 318-14 code method is used benefiting from iterative particle swarm optimization technique due to its efficiency and reliability. Minimizing total cost is used as the objective function in terms of four decision variables. Self-adaptive penalty function technique is used to handle constraints for each of the 300 randomly selected particles, and in each …

Interaction Between Fusarium Head Blight And Crown Rot Disease Incidence And Environmental Factors And Soil Physiochemical Analysis On Wheat In The South Of Iraq, Basra Province, Mohammed Hussein Minati Dr., Mohanad Khalaf Mohammed-Ameen Dr.

Karbala International Journal of Modern Science

This study was conducted to evaluate the interaction between disease incidence of both Fusarium head blight (FHB) and crown rot (FCR) and physiochemical parameters for soil samples and environmental factors in 14 selected wheat fields in the North of Basra province. The results showed that both diseases were occurred in all surveyed fields. The level of FCR incidence was higher than FHB. The incidence of both diseases was increased with favourable weather conditions (high humidity and temperature ˃15 °C), reaching the highest levels in crucial periods before and during the ripening stage. The percentage of disease incidence ranged between 6 …

Artificial Bee Colony Algorithm For Solving Fuzzy Multi-Objective Bed Allocation Model, Abdulhakeem Luqman Hasan

Karbala International Journal of Modern Science

With the improvement of the medical services frameworks rivalry, hospitals face more and more challenges. In the interim, allotment of resource has a crucial influence on performing competitive benefits in a hospitals. To choose the suitable beds number is one of the most essential tasks in hospital administration. Anyway, in true condition, bed allotment choice is a multiple-side problem with weakness and haphazardness of the information available. It is so sophisticated. Therefore, the research about bed allotment difficulty is comparatively rare under considering multiple departments, nursing hours, and stochastic information about arrival and service of patients. In this paper, we …

Evaluation Of Atmospherically Gases Using Models Flaash And Quac To Hyper-Spectral Imagery, Asmaa Maher

Karbala International Journal of Modern Science

The important step is correction of the effect of atmospheric on hyper-spectral imagery of the VIS “visible”, short wave & NIR “near-infrared” spectral range. In general, the cause for limiting the use of hyperspectral images is the atmospheric effects, so, atmospheric correction is necessary for any accurate processing. In this work, two atmospheric correction techniques have been applied on Hyper-spectral image. From the raw original image and also from the FLAASH and QUAC atmospheric corrected images the spectra of vegetation, water and soil were extracted. The acquisition data for study contained Hyperion bands for year “2015” images over each of …