Biology Commons^™

Biophysical Investigation Of The Cataract Associated Mutant, E107a Of Human Gamma-D Crystalline And Constructing A Fluorescent System For Manipulating Pip2 Concentration In The Plasma Membrane Of Xenopus Oocytes., Julita Patrosz

Biological Sciences

Chapter 1: Biophysical investigation of the cataract associated mutant, E107A of human gamma-D crystallin. Several human genetic cataracts are associated with mutations in a single amino acid residue of the protein known as D crystallin. Recently, the Glu107Ala (or E107A) mutation has been included in this list, and it has been associated with a nuclear congenital cataract. We have made recombinant human D crystallin and its E107A mutant and conducted preliminary comparisons of its structure and biophysical properties with that of the wild-type protein. In this process we made use of several techniques – Circular Dichroism (CD), Iso-electric focusing (IEF) …

The Anti-Epileptic Drugs Phenytoin And Valproate Produce Reproductive Endocrine Dysfunction Among Reproductive Endocrine Dysfunction Among Female Rats Through Its Effects On Progesterone And Its 5 Alpha-Reduced Metabolites, Fareed Haddad

Biological Sciences

Background: Many people with seizure disorder experience reproductive endocrine dysfunction (RED). The extent to which RED is due to intrinsic aspects of seizure disorder, and/or therapies used to manage epilepsy, is not well understood. Many anti-epileptic drugs (AEDs), such as phenytoin or valproate, can have effects that alter endocrine status. Phenytoin is a cytochrome p450 enzyme-inducing drug. Valproate is a cytochrome p450 enzyme-reducing AED. Objective: To evaluate the effects and mechanism of some AEDs on RED in a rodent model. Hypothesis: If AEDs produce RED in part by altering the activities of cytochrome p450 enzymes, then AEDs that disrupt estrous …

1 The Mechanical Function Of The Postorbital Bar In Eulemur Fulvus Analyzed Using Finite Element Analysis, Danielle Parisi

Biological Sciences

No abstract provided.

Ethnobotanical History And Seed Oil Chemistry Of The Physic Nut, Jatropha Curcas, Nathan M. Leclear

Theses and Dissertations - UTB/UTPA

Jatropha curcas L., Euphorbiaceae, is a small tree native to the neotropics. Despite renewed economic interests in Physic Nut, mainly for biodiesel production, a comprehensive analysis of the ethnobotanical history of J. curcas is lacking. An account of the pre-Columbian neotropical distribution of this species and its historical uses are presented. Using capillary gas chromatography, studies were conducted to quantify the natural variation in seed oil content and fatty acid composition of the seed oil from several species of Jatropha, including assessment of how these parameters change during seed maturation. Natural variation in seed oil content was detected (F7,93 = …

The Effects Of Betadine®, Polyvinylpyrrolidone (Pvp), And Iodine On Regeneration In The Planarian Dugesia Tigrina., Traci R. Shaffer

Electronic Theses and Dissertations

The freshwater planarian has a great capacity to regenerate and is an ideal animal model in the study of stem cell and regeneration biology. In this study planarian regenerating new tails were exposed to nonlethal doses of Betadine®, Polyvinylpyrrolidone (PVP), and Iodine. Betadine® is a topical antiseptic commonly used in the healthcare setting and may have a detrimental effect on wound healing. PVP is linked to iodine to create povidone-iodine, the active ingredient in Betadine®. Initially, a preliminary test was performed on the worms to determine the nonlethal concentrations of these chemicals . After this nonlethal concentration was determined, tails …

Effects Of Pluronics On A Beneficial Soil Microbe Pseudomonas Putida Strain Kt2440, Priyanka Gajjar

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report summarizes the effects of a range of Pluronics on cellular responses in bacterial and mammalian cells through a review of published findings. Effects of Pluronics on drug delivery, efflux systems, growth, and nutrition are reported for eukaryotic cells. For microbial cells, their effects on adhesion, movement, biofilm formation, energy status and secondary metabolism are discussed. Guided by findings in the literature, a series of experiments were conducted exploring the responses of a beneficial environmental soil microbe, Pseudomonas putida strain KT2440, to selected Pluronics. These results are presented. The report has four sections: an Introduction 4 that covers published …

Preeclampsia, Autoimmunity And The At1 Receptor, Roxanna A. Irani

Dissertations and Theses (Open Access)

Preeclampsia (PE) is a disease of late pregnancy characterized by maternal hypertension and proteinuria. It is associated with preterm delivery and significant perinatal morbidity and mortality. Despite affecting ~7% of first pregnancies, there is no effective screening method to identify women at risk, nor is there a definitive treatment other than delivery of the baby and placenta. Though the pathogenesis of PE remains unclear, an imbalance in the renin-angiotensin and immune systems are thought to be major contributors. Bridging these two concepts, it has recently been shown that women with PE harbor specific autoantibodies: the angiotensin II type 1 receptor …

Gsk3 Mediates Signaling Upstream Of Akt, Debra L. Smith

Dissertations and Theses (Open Access)

The phosphatidylinositide 3 kinase (PI3K)/Akt signaling network plays a pivotal role in multiple cellular functions. PI3K links the extracellular growth factor receptors to the serine-threonine kinase Akt which, through phosphorylation of numerous intracellular proteins, mediates increased cell growth, survival, motility and proliferation. The significance of the PI3K/Akt signaling network to human malignancy is demonstrated by cancer-associated genetic aberrations at multiple levels in the PI3K/Akt pathway in many tumor lineages. These aberrations include mutation or amplification of Akt, catalytic and regulatory subunits of PI3K, and growth factor receptors upstream of PI3K. Inactivating mutations and decreased expression of the PTEN, a major …

Myogenin Modulates Exercise Endurance By Altering Skeletal Muscle Metabolism, James Eric Meadows

Dissertations and Theses (Open Access)

The function of myogenic regulatory factors (MRFs) during adult life is not well understood. The requirement of one of these MRFs, myogenin (Myog), during embryonic muscle development suggests an equally important role in adult muscle. In this study, we have determined the function of myogenin during adult life using a conditional allele of Myog. In contrast to embryonic development, myogenin is not required for adult viability, and Myog-deleted mice exhibited no remarkable phenotypic changes during sedentary life. Remarkably, sedentary Myog-deleted mice demonstrated enhanced exercise endurance during involuntary treadmill running. Altered blood glucose and lactate levels in sedentary Myog-deleted mice after …

A New Tumor Suppressor Gene Candidate Regulated By The Non-Coding Rna Pca3 In Human Prostate Cancer, Alessandro K. Lee

Dissertations and Theses (Open Access)

Prostate cancer is the second leading cause of cancer-related death and the most common non-skin cancer in men in the USA. Considerable advancements in the practice of medicine have allowed a significant improvement in the diagnosis and treatment of this disease and, in recent years, both incidence and mortality rates have been slightly declining. However, it is still estimated that 1 man in 6 will be diagnosed with prostate cancer during his lifetime, and 1 man in 35 will die of the disease.

In order to identify novel strategies and effective therapeutic approaches in the fight against prostate cancer, it …

The Consequences Of Disrupting The Mdm2-P53 Balance In Hematopoiesis, Hussein A. Abbas

Dissertations and Theses (Open Access)

The bone marrow accommodates hematopoietic stem cells and progenitors. These cells provide an indispensible resource for replenishing the blood constituents throughout an organism’s life. A tissue with such a high turn-over rate mandates intact cycling checkpoint and apoptotic pathways to avoid inappropriate cell proliferation and ultimately the development of leukemias. p53, a major tumor suppressor, is a transcription factor that regulates cell cycle, and induces apoptosis and senescence. Mice inheriting a hypomorphic p53 allele in the absence of Mdm2, a p53 inhibitor, have elevated p53 cell cycle activity and die by postnatal day 13 due to hematopoietic failure. Hematopoiesis progresses …

New Target Genes For Tumor Suppressors P53 And P73 In Regenerating Liver, Svitlana M. Kurinna

Dissertations and Theses (Open Access)

The p53-family of proteins regulates expression of target genes during tissue development and differentiation. Within the p53-family, p53 and p73 have hepatic-specific functions in development and tumor suppression. Despite a growing list of p53/p73 target genes, very few of these have been studied in vivo, and the knowledge regarding functions of p53 and p73 in normal tissues remains limited. p53+/-p73+/- mice develop hepatocellular carcinoma (HCC), whereas overexpression of p53 in human HCC leads to tumor regression. However, the mechanism of p53/p73 function in liver remains poorly characterized. Here, the model of mouse liver regeneration is used to identify new target …

Learning Ability And Factors Influencing Nest Establishment Of The Solitary Bees Osmia Lignaria And Megachile Rotundata (Hymenoptera: Megachilidae), Cory A. Vorel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last several decades, the use of solitary bees as an alternative to honey bees (Apis mellifera L.) for pollination of commercial crops has increased, in part as a response to ongoing problems faced by commercial honey bee populations. Two solitary bee species have exhibited great commercial potential: the blue orchard bee, Osmia lignaria Say, and the alfalfa leafcutting bee, Megachile rotundata Fabricius (Hymenoptera: Megachilidae). However, growth of O. lignaria and M. rotundata populations is limited in commercial systems, mainly due to low establishment of females at provided nesting sites, possibly due to mortality, dispersal, or other causes. …

Targeting Fatty Acid-Activated Pathways In The Somatosensory System, Tian Yu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Given the dramatic rise in obesity and the diseases linked with it, it is becoming increasingly important to understand the mechanisms that underlie the body's ability to recognize fat. The chemoreception of dietary fat in the oral cavity has largely been attributed to activation of the somatosensory system that relays the textural properties of fat. However, the ability of fatty acids, which are believed to represent the proximate stimulus for fat taste, to activate trigeminal ganglionic neurons has remained unexplored. In general, my research has provided the first evidence of fatty acids activating the somatosensory system by increasing the intracellular …

Farnesol Signaling In Candida Albicans, Melanie L. Langford

School of Biological Sciences: Dissertations, Theses, and Student Research

Candida albicans is a polymorphic fungus that causes a range of disease in humans, from mucosal infections to systemic disease. Its ability to cause disease is linked to conversion between yeast and filamentous forms of growth, and the first quorum-sensing molecule discovered in an eukaryote, farnesol, blocks this transition. In C. albicans, farnesol also kills mating-competent opaque cells, inhibits biofilm formation, protects the cells from oxidative stress, and can be a virulence factor or protective agent in disseminated and mucosal mouse models of infection, respectively. While much emphasis has been placed on determining its effect on C. albicans morphology, …

Annual Rainfall And Seasonality Predict Pan‐Tropical Patterns Of Liana Density And Basal Area, Saara J. Dewalt, Stefan A. Schnitzer, Jérôme Chave, Frans Bongers, Robyn J. Burnham, Zhiquan Cai, George B. Chuyong, David B. Clark, Corneille E.N. Ewango, Jeffrey J. Gerwing, Esteban Gortaire, Terese Hart, Guillermo Ibarra-Manriquez, Kalan Ickes, David Kenfack, Manuel J. Macía, Jean-Remy Makana, Miguel Martinez-Ramos, Joseph Mascaro, Sainge Moses, Helene C. Muller-Laudau, Marc P.E. Parren, Narayanaswamy Parthasarathy, Diego R. Perez-Salicrup, Francis E. Putz, Hugo Romero-Saltos, Duncan W. Thomas

Biological Sciences Faculty Research and Publications

We test the hypotheses proposed by Gentry and Schnitzer that liana density and basal area in tropical forests vary negatively with mean annual precipitation (MAP) and positively with seasonality. Previous studies correlating liana abundance with these climatic variables have produced conflicting results, warranting a new analysis of drivers of liana abundance based on a different dataset. We compiled a pan‐tropical dataset containing 28,953 lianas (≥2.5 cm diam.) from studies conducted at 13 Neotropical and 11 Paleotropical dry to wet lowland tropical forests. The ranges in MAP and dry season length (DSL) (number of months with mean rainfall < 100 mm) represented by these datasets were 860–7250 mm/yr and 0–7 mo, respectively. Pan‐tropically, liana density and basal area decreased significantly with increasing annual rainfall and increased with increasing DSL, supporting the hypotheses of Gentry and Schnitzer. Our results suggest that much of the variation in liana density and basal area in the tropics can be accounted for by the relatively simple metrics of MAP and DSL.

Does The Manipulation Of Tail Position Facilitate Extinction Of Canine Phobic Behavior?, Rebecca A. Zarate

Theses and Dissertations - UTB/UTPA

The phobic behavior of interest is tail tucking which is indicative of submission. In this study the tail was physically manipulated by the use of a custom made harness to hold the tail up in a dominant position to ideally extinguish phobic behavior through reciprocal inhibition. The harness did not hold the tail up the entire duration of the interventions, although it still held the base of the tail up. The intervention did not appear to have an affect on the two of the five subjects. The three more phobic canines did display some behavioral changes, although the changes noticed …

Phylogeography Of Two Closely Related Anurans, The Relict Leopard Frog (Rana Onca) And Lowland Leopard Frog (Rana Yavapaiensis), Viktoria Hemmings

UNLV Theses, Dissertations, Professional Papers, and Capstones

I investigate the phylogeography of the relict and lowland leopard frogs (Rana onca; R. yavapaiensis) inhabiting the Mojave and Sonoran deserts. In Chapter 1, I summarize literature describing taxonomy, phylogenetics, and the possible effects of Quaternary climate change on distribution. Examples of phylogeographic patterns from generally co-distributed organisms are provided to develop background for interpreting the structure. In Chapter 2, I investigate the phylogeography of these frogs using mitochondrial DNA data. The analysis supports a previously determined phylogenetic break between taxa however further dividing R. yavapaiensis into two lineages. I estimate a possible Early Pleistocene divergence of R. onca and …

Bronzed Cowbird (Molothrus Aeneus) Habitat Use And Differential Response To Playback Of Host Song, Mary Jennifer Gorton

Theses and Dissertations - UTB/UTPA

During the breeding seasons of 2008 - 2009, 180 fixed-radius point-count surveys and broadcasts of host song were conducted in Santa Ana (SANWR) and Laguna Atascosa (LANWR, 2009 only) National Wildlife Refuges to identify Bronzed Cowbird (Molothrus aeneus) habitat use and test the predictions of the host activity hypothesis. Surveys demonstrated that Bronzed Cowbirds were distributed across all habitat types in both refuges, although there were differences in abundance between the sexes for interior and edge habitats and between habitat types. Bronzed Cowbirds responded differentially to host species playbacks based on suitability and abundance of the host species. The results …

Biogeography And Microhabitat Distribution Of Myxomycetes In High-Elevation Areas Of The Neotropics, Carlos Alonso Rojas-Alvarado

Graduate Theses and Dissertations

Myxomycetes are a group of amoeboid organisms with the capacity of forming fruiting bodies that resemble some macrofungi. The ecology and global distribution of species within the group have been studied only during the last half century. For this reason, a number of questions regarding the nature of the interactions that exist between myxomycetes and their environment still lack the empirical evidence required to obtain complete answers. In the Neotropical region, species assemblages have been moderately well studied, but their biogeography and macroecology have received little attention. In high-elevation areas of this region, the situation is especially precarious, due the …

Habitat Variables, Mammal Interactions, And Recovery Approaches Important To A Rare, New Mexican Butterfly, Euphydryas Anicia Cloudcrofti (Lepidoptera: Nymphalidae), Julie Lincoln Mcintyre

Biology ETDs

This research investigated three study topics pertaining to the habitat and ecology of the Sacramento Mountains checkerspot butterfly (Euphydryas anicia cloudcrofti) with the goal of contributing to effective conservation for this rare species. In the first study, abiotic and biotic habitat variables were found to be different between occupied and unoccupied habitat. Connectivity, host plant resource concentration, and plant structural diversity corresponded with butterfly presence at the scales of landscape, meadow, host plant patch, and natal host plant. High habitat quality, low isolation, broad host plant patch area, and high host plant patch density were associated with occupied habitats. Adults …

Tracing Deuterium Through The Food Web And Into Birds And Mammals Along An Elevational Gradient In The Southern Rocky Mountains, Matthew J. Baumann

Biology ETDs

Animals incorporate local δ2H values from available water and dietary sources during tissue synthesis, which can provide evidence of elevational movements if multiple tissues with different turnover times are examined. Here we test the applicability of using δ2H as an indicator of altitudinal movements by examining multiple tissues (δ2Hbw (body water), δ2Hfeather, δ2Hfur, and δ2Hclaw) in birds and mammals in the Sangre de Cristo Mountains. Additionally, we measured δ2Hsw (stem water) and insect δ2bw and δ2wb (whole body) values to assess changes with elevation. We sampled 15 species of birds and two small mammal species along with potential food sources …

Dispersal, Facilitation, And Burrow Architecture In Banner-Tailed Kangaroo Rats, Andrew J. Edelman

Biology ETDs

The largest and most dominant kangaroo rat species in the Chihuahuan Desert is the banner-tailed kangaroo rat (Dipodomys spectabilis). This keystone species constructs mounds containing a complex burrow system around which their ecosystem engineering activities are centered. I studied a population of banner-tailed kangaroo rats at the Sevilleta National Wildlife Refuge, New Mexico from 2005-2009. Specifically, I examined how banner-tailed kangaroo rats: 1) modify their mounds in response to seasonal conditions; 2) spatially affect harvester ants (Pogonomyrmex rugosus) through ecosystem engineering activities; and 3) differ in timing of natal dispersal between sexes. I used mark-recapture, genetic, experimental, and spatially-explicit methods …

Respiratory Physiology During Gravidity In Crotaphytus Collaris And Gambelia Wislizenii, Casey Anderson Gilman

Biology ETDs

During gravidity lizards experience a significant decrease in lung volume as a result of compression by growing eggs within the body cavity. In order to understand the effect of this decrease in lung volume on respiratory physiology of gravid egg-laying lizards I measured changes in: total lung volume, resting and post-exercise expired volume, minute volume, respiratory frequency, and carbon dioxide production during reproduction in Crotaphytus collaris and Gambelia wislizenii. I found that compression of the lungs by eggs resulted in an average 48% (range: 26 to 70%) decrease in total lung volume in C. collaris, and an average 38% (range: …

Molecular Phylogenetic Investigation Of Microbial Diversity And Nitrogen Cycling In Lava Tubes, Jennifer Jane Marshall Hathaway

Biology ETDs

Worldwide, lava tubes host colorful microbial mats on their walls and ceilings. Little is known about the diversity and ecological roles of the bacteria communities in the subsurface ecosystem of lava tubes. White and yellow microbial mats were collected from four lava tubes from the Azorean island of Terceira and from four lava tubes on the Big Island of Hawaii, to compare and contrast the diversity of bacteria found in lava tubes. The 16S rRNA gene was sequenced in order to determine the diversity within these caves, and to begin to elucidate the environmental controls on microbial diversity in the …

Relationships Between Particle Properties And Scattering In Coastal Waters Of The Northern Gulf Of Mexico Influenced By The Mississippi River, Bruce Alan Spiering

Dissertations

This study was conducted to determine how the characteristics of an assemblage of suspended particles, including their composition and size affect the relationship between the optical scattering coefficient b (m-1), and the dry mass of the particles in suspension. Knowledge of the scattering to total suspended matter (TSM) ratio, i.e. the mass specific scattering coefficient b* (m2/g), is important because the light detected by optical imaging sensors used for remote sensing is the light that has been scattered by particles back through the water surface. If this ratio is not known or varies within the region of interest, accurate estimates …

The Role Of Il-1beta, Il-6, And Tnf-Alpha In Radiation-Induced Bone Loss, Stephanie Riffle

All Theses

Bone fractures greatly decrease an individual's quality of life, as well as increase an individual's risk for further complications, including death. Ionizing radiation causes bone loss, leaving bones at increased risk of fracture. This exposure, particularly in the context of cancer patients receiving radiotherapy, results in damage to normal (non-tumor) tissue. Inflammation is a common response to radiation-induced tissue damage, characterized by increased presence of pro-inflammatory cytokines, such as IL-1beta, IL-6, and TNF-alpha. However, little is known about the roles of these cytokines in radiation-induced bone loss. This thesis hypothesized that the up regulation of pro-inflammatory cytokines (IL-1beta, IL-6, and …

Assessment Of Different Seed Mixture Planting Using Ground Beetles (Coleoptera, Carabidae) As Environmental Indicators Along A Disturbance Corridor In Lawrence County, Kentucky, Michelle M. Staley

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michelle M. Staley on April 30, 2010.

Spatial And Temporal Distribution Of Larval Fishes In A Large Tidal River., Harold Seelig

Theses and Dissertations

There are few published studies of larval fish assemblages from unregulated, tidal freshwater rivers. Patterns in the spatial and temporal distribution of larval fishes in the Mattaponi River were examined. Sampling took place on a weekly basis from February through August, 2006 and 2007. Larval fishes were categorized by taxa, reproductive guild, and residency guild. Group comparisons using multi-response permutation procedures (MRPP) indicated significant spatial and temporal differences in assemblage composition on multiple scales. Differences in assemblage composition were analyzed using non-metric multidimensional scaling (NMS). Interannual differences were attributable to anadromous and semi-migratory species. Seasonal differences were attributable to herrings, …

Expression & Purification Of Recombinant Plasmodium Falciparum Erythrocyte-Binding Ligands, Seward Joann Cofie

Theses and Dissertations

Plasmodium falciparum, the most virulent malarial parasite, is capable of invading all known human blood types. Erythrocyte invasion depends on specific parasite ligand and erythrocyte receptor interactions. These interactions are mediated by Region II of the P. falciparum erythrocyte binding ligands. Although invasion does not seem dependent upon a singular ligand, their individual contributions to the invasion process are yet to be explained. In this study, Region II of P. falciparum binding ligands BAEBL and JESEBL were transiently expressed as hexahistidyl recombinant proteins in COS-1 cells. Purification by column chromatography yielded 0.52 mg of BAEBL and 0.433 mg of JESEBL. …