Life Sciences Commons^™

An Engineered Nonsense Ura3 Allele Provides A Versatile System To Detect The Presence, Absence And Appearance Of The [Em>Psi+] Prion In Saccharomyces Cerevisiae, Anita L. Manogaran, Kathryn T. Kirkland, Susan W. Liebman

Biological Sciences Faculty Research and Publications

Common methods to identify yeast cells containing the prion form of the Sup35 translation termination factor, [PSI⁺], involve a nonsense suppressor phenotype. Decreased function of Sup35p in [PSI⁺] cells leads to readthrough of certain nonsense mutations in a few auxotrophic markers, for example, ade1-14. This readthrough results in growth on adenine deficient media. While this powerful tool has dramatically facilitated the study of [PSI⁺], it is limited to a narrow range of laboratory strains and cannot easily be used to screen for cells that have lost the [PSI^{+ …}

New Bioassay Method To Assess The Pathogenicity Of Colombian Strains Of Metarhizium Anisopliae (Metsch.) Sorokin And Paecilomyces Sp. (Deuteromycotina: Hyphomycetes) Against The Subterranean Burrower Bug Cyrtomenus Bergi Froeschner (Hemiptera: Cydnidae), Juliana Jaramillo, Christian Borgemeister

All Peer-Reviewed Publications

Using a new sand bioassay method, the pathogenicity of three Colombian strains of Metarhizium anisopliae (i.e., CIAT 224, 245, and 230) and one strain of Paecilomyces sp. (CIAT 308) were tested against fourth instars of the subterranean burrower bug Cyrtomenus bergi Froeschner (Hem.: Cydnidae) in the laboratory. The proposed bioassay simulates the habitat of C. bergi and at the same time enables the evaluation of a large number of insects in a short period of time and under controlled conditions. All tested fungal species/strains were pathogenic against C. bergi. However, only low levels of mortality were obtained, and never exceeded …

The Dot Chromosome Of Drosophila: Insights Into Chromatin States And Their Change Over Evolutionary Time, Nicole Riddle, Sarah C.R. Elgin

Biology Faculty Research

Historically, chromatin has been subdivided into heterochromatin, transcriptionally inactive regions that remain densely packaged throughout the cell cycle, and euchromatin, transcriptionally active regions that take on a diffuse appearance as the cell enters interphase. The banded portion of the small fourth chromosome (dot chromosome) of Drosophila melanogaster is unusual in exhibiting many characteristics of heterochromatic domains, and at the same time maintaining a gene density typical of euchromatin. Similar to genes embedded in pericentric heterochromatin, many of the dot chromosome genes have adapted to a heterochromatic environment. Little is known about the regulation of these genes and less about their …

The Involvement Of Calcium And Map Kinase Signaling Pathways In The Production Of Radiation-Induced Bystander Effects, Fiona Lyng, Paula Maguire, B. Mcclean, C. Seymour, Carmel Mothersill

Articles

Much evidence now exists regarding radiation-induced bystander effects, but the mechanisms involved in the transduction of the signal are still unclear. The mitogen-activated protein kinase (MAPK) pathways have been linked to growth factor-mediated regulation of cellular events such as proliferation, senescence, differentiation and apoptosis. Activation of multiple MAPK pathways such as the ERK, JNK and p38 pathways have been shown to occur after exposure of cells to radiation and a variety of other toxic stresses. Previous studies have shown oxidative stress and calcium signaling to be important in radiation-induced bystander effects. The aim of the present study was to investigate …

Disinfection Of Swine Wastewater Using Chlorine, Ultraviolet Light And Ozone, John J. Macauley, Zhimin Qiang, Rao Y. Surampalli, Melanie R. Mormile, Craig D. Adams

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Veterinary antibiotics are widely used at concentrated animal feeding operations (CAFOs) to prevent disease and promote growth of livestock. However, the majority of antibiotics are excreted from animals in urine, feces, and manure. Consequently, the lagoons used to store these wastes can act as reservoirs of antibiotics and antibiotic-resistant bacteria. There is currently no regulation or control of these systems to prevent the spread of these bacteria and their genes for antibiotic resistance into other environments. This study was conducted to determine the disinfection potential of chlorine, ultraviolet light and ozone against swine lagoon bacteria. Results indicate that a chlorine …

Evaluating The Biogeochemical Cycle Of Selenium In San Francisco Bay Through Modeling, Shannon L. Meseck, Gregory A. Cutter

OES Faculty Publications

A biogeochemical model was developed to simulate salinity, total suspended material, phytoplankton biomass, dissolved selenium concentrations (selenite, selenate, and organic selenide), and particulate selenium concentrations (selenite + selenate, elemental selenium, and organic selenide) in the San Francisco Bay estuary. Model-generated estuarine profiles of total dissolved selenium reproduced observed estuarine profiles at a confidence interval of 91- 99% for 8 different years under various environmental conditions. The model accurately reproduced the observed dissolved speciation at confidence intervals of 81-98% for selenite, 72-91% for selenate, and 60-96% for organic selenide. For particulate selenium, model-simulated estuarine profiles duplicated the observed behavior of total …

Dynamics Of Carbon Allocation In A Deep-Water Population Of The Deciduous Kelp Pleurophycus Gardeneri (Laminariales), Clare M. Dominik, Richard C. Zimmerman

OES Faculty Publications

Pleurophycus gardneri (Laminariales) is common in the low intertidal of the Northeast Pacific, but dominates many deep (30 to 40 m) rocky reefs in central California. Seasonal dynamics of productivity and resource allocation of a deep-water population of this deciduous, stipitate kelp were studied to understand how blade abscission affects the annual carbon budget. Patterns of growth, metabolism, and carbon storage and mobilization were measured monthly for 1 yr relative to in situ light and temperature, and used to model the annual carbon budget. The resulting carbon budget was used to determine if blade abscission effectively reduced respiratory demand during …

Nitrogen Fixation And Release Of Fixed Nitrogen By Trichodesmium Spp. In The Gulf Of Mexico, Margaret R. Mulholland, Peter W. Bernhardt, Cynthia A. Heil, Deborah A. Bronk, Judith M. O'Neil

OES Faculty Publications

During a 3-yr study in the Gulf of Mexico, we measured dinitrogen (N₂) fixation and nitrogen (N) release by Trichodesmium and compared these rates with water column N demand and the estimated N necessary to support blooms of Karenia brevis, a toxic dinoflagellate that severely affects the West Florida shelf. Net and gross N₂ fixation rates were compared in simultaneous incubations using ¹⁵N₂ uptake and acetylene reduction, respectively. The difference between net and gross N₂ fixation is assumed to be an approximation of the rate of N release. Results demonstrate that Trichodesmium in …

The Role Of Lipids During Embryonic Development Of The Euphausiids Euphausia Pacifica And Thysanoessa Spinifera, Se-Jong Ju, H. Rodger Harvey, Jaime Gómez-Gutiérrez, William T. Peterson

OES Faculty Publications

To understand the role of lipids during early embryogenesis, major lipid classes together with individual fatty acid and sterol composition were determined in embryos from multiple developmental stages of the euphausiids Euphausia pacifica and Thysanoessa spinifera. Average lipid content in embryos of E. pacifica and T. spiniferafrom the earliest stage (multicell) were 4.45 and 3.69 µg embryo^-1,respectively. During development, the lipid content decreased at similar rates in the embryos of both species. In contrast to many crustacean eggs, phospholipids were the dominant lipid class in all embryonic stages, with decreasing concentrations seen during development. Individual …

Angiotensin Ii And Aldosterone Increase With Fasting In Breeding Adult Male Northern Elephant Seals (Mirounga Angustirostris), Rudy M. Ortiz, Daniel E. E. Crocker, Dorian S. Houser, Paul M. Webb

Arts & Sciences Faculty Publications

The renin‐angiotensin‐aldosterone system (RAAS) appears to contribute significantly to osmoregulation of fasting northern elephant seal (Mirounga angustirostris) pups; however, RAAS has not been characterized in fasting adult seals. Therefore, this study examined the contribution of RAAS to water turnover rates in fasting adult male northern elephant seals. Blood samples were obtained twice during their breeding fast at an interval of 6.5 wk, and water efflux rate was estimated by isotopic dilution during the same period. Serum electrolytes (Na⁺, K⁺, Cl⁻) and osmolality were unaltered between the two sampling periods, indicating ionic and …

High-Level Resistance To Moxifloxacin And Gatifloxacin Associated With A Novel Mutation In Gyrb In Toxin-A-Negative, Toxin-B-Positive Clostridium Difficile, Denise Drudy, T. Quinn, R. O'Mahony, L. Kyne, P. O'Gaora, S. Fanning

Articles

OBJECTIVES:

To determine the mechanism of high-level resistance to fluoroquinolone antimicrobials in toxin-A-negative, toxin-B-positive (A- B+) Clostridium difficile isolates.

METHODS:

Following culture 16-23S PCR ribotyping was used to determine genomic relationships between A- B+ C. difficile isolates. Antimicrobial susceptibilities were determined using Etests in the presence and absence of the efflux pump inhibitors reserpine (20 microg/mL), L-phenylalanine-L-arginine-beta-naphthylamide (PAbetaN; 20 microg/mL) and verapamil (100 microg/mL). Genomic regions including the quinolone-resistance-determining-region (QRDR) of gyrA and gyrB were amplified and characterized.

RESULTS:

PCR ribotyping profiles identified one major cluster of A- B+ C. difficile, universally resistant to the fluoroquinolones tested (ofloxacin, ciprofloxacin, levofloxacin, …

Characterisation Of Cell Types In Abalone (Haliotis Spp.) Tissues Using Immunohistochemical Techniques, Leanne Harris, Nuala O'Byrne-Ring, Helen Lambkin

Articles

The increasing popularity of abalone as a seafood delicacy has led to the rapid development of abalone aquaculture worldwide. The commercial and economic importance of this industry has resulted in an increasing interest in the biology of this particular shellfish genus. In this study we focus on the identification of structural, functional and proliferative proteins in two species of abalone shellfish, Haliotis discus hannai and Haliotis tuberculata. Monoclonal and polyclonal antibodies that react with proteins in vertebrate and invertebrate tissues were selected and applied to abalone tissues. Cross sections of whole animals were analysed using avidin–biotin immunoperoxidase staining protocols. In …

Generality Of Vertebrate Developmental Patterns: Evidence For A Dermomyotome In Fish, S. H. Devoto, W. Stoiber, C. L. Hammond, P. Steinbacher, J. R. Haslett, M. J.F. Barresi, S. E. Patterson, E. G. Adiarte, S. M. Hughes

Biological Sciences: Faculty Publications

The somitic compartment that gives rise to trunk muscle and dermis in amniotes is an epithelial sheet on the external surface of the somite, and is known as the dermomyotome. However, despite its central role in the development of the trunk and limbs, the evolutionary history of the dermomyotome and its role in nonamniotes is poorly understood. We have tested whether a tissue with the morphological and molecular characteristics of a dermomyotome exists in nonamniotes. We show that representatives of the agnathans and of all major clades of gnathostomes each have a layer of cells on the surface of the …

Influences Of Host Size And Host Quality On Host Use In A Seed-Feeding Beetle, Angela Rocío Amarillo-Suárez

University of Kentucky Doctoral Dissertations

For insects that develop inside discrete hosts both host size and host quality constrain offspring growth, influencing the evolution of body size and life history traits. This dissertation examines the effects of host size, host quality, and intraspecific competition on life history and associated traits of populations of the seed-feeding beetle S. limbatus adapted to different host plants, and quantifies population differences in phenotypic plasticity. Populations of the study correspond to divergent clades of the species phylogeography (Colombia and United States).

Clades compared differ genetically for all traits when beetles were raised in a common garden. Contrary to expectations from …

Phylogeography Of Marine Meiofaunal Nemerteans Of The Ototyphlonemertes Fila Species Complex, Alexander Tulchinsky

Theses and Dissertations

Morphological conservatism combined with intraspecific variability has obstructed studies of speciation and species boundaries among marine meiofauna. Ototyphlonemertes is a genus of meiofaunal nemerteans inhabiting the interstitial spaces of marine sediments. Its members lack pelagic larvae and dispersal potential is believed to be poor. A phylogeographic study of Ototyphlonemertes fila is presented using mitochondrial (cox3) and nuclear (ISSR) molecular markers. Deep genetic divergence (approximately 18% in cox3) was observed between sympatric mitochondrial lineages in Florida. This divergence was reflected in the nuclear marker as well, suggesting the presence of two cryptic species. The first contains Florida and New England populations …

Development Of Single Nanoparticle Optical Assays For Imaging Single Living Cells, William John Brownlow

Chemistry & Biochemistry Theses & Dissertations

Multi-drug resistance (MDR) has been reported in both prokaryotes and eukaryotes; the pathogenic gram-negative bacteria Pseudomonas aeruginosa can extrude a variety of structurally and functionally diverse substrates via a number of membrane transport systems leading to MDR. We have developed a novel nanoparticle assay to characterize both the membrane transport system composed of the MexAB-OprM efflux pump and the membrane permeability induced by antibiotics. Gold (Au) and silver (Ag) nanoparticles were investigated for use as probes to explore membrane transport in P. aeruginosa.

The surface plasmon absorption (color) of Au nanoparticle solutions was found to change in the presence …

I. Comparison Of Translesion Bypass Of Guanine–N2 Monoadducts Of Mitomycin C And Guanine-N7 Monoadducts Of 2,7-Diaminomitosene By T7 Exo-, Klenow Exo-, Eta And Klenow Exo+ Dna Polymerases. Ii. Structure-Based Design, Synthesis, Structure-Conformation And Structure-Activity Relationships Studies Of D-Phe-Pro-D-Arg-P1’-Conh2 Tetrapeptides With Inhibitory Activity For Thrombin., Cristina C. Clement

Dissertations, Theses, and Capstone Projects

The guanine (G)-N² DNA monoadduct of mitomycin C (MC), a cytotoxic anticancer drug, inhibits translesion bypass by DNA polymerases. 2,7-Diaminomitosene (2,7-DAM) is the major metabolite of MC in tumor cells, generated by the reduction of MC. 2,7-DAM alkylates DNA in the cell in situ, forming an adduct at the N7 position of 2'-deoxyguanosine (2,7-DAM-dG) and is noncytotoxic. In part I of this study we tested a potential correlation between the lack of cytotoxicity of 2,7-DAM and the relative ease of bypass of this adduct as compared with the MC adduct. 24-mer and 27-mer templates, adducted at a single …

Identification Of A Lactic Bacterium Strain Used For Obtaining A Pollen-Based Probiotic Product, Adrian Vamanu, Emanuel Vamanu, Manuel Drugulescu, Ovidiu Popa, Gheorghe Campeanu

Turkish Journal of Biology

This study concerns the identification of a Lactobacillus acidophilus strain by conventional taxonomic techniques (cultivation at different temperatures, different pH values, use of different carbon sources, development on different media and determination of antibioresistance) and by molecular genetic techniques (determination of G and C content). The strain is used for inoculation in media with ground or unground pollen and honey, in order to obtain a probiotic product. Over 72 h the glucid consumption, cell viability and acid production is measured.

Nucleic Acid Extraction From Clinical Specimens For Pcr Applications, Ashabil Aygan

Turkish Journal of Biology

Polymerase chain reaction (PCR) has been widely used due to its high specificity, sensitivity, and rapid turn-around time. However, the major limitation of PCR based diagnosis is inhibition of the reaction caused by a variety of components within clinical specimens. The demand for PCR diagnosis in medical microbiology has highlighted the need for efficient methods of nucleic acid extraction. Although there has been progress in the simplification and purification of microbial nucleic acids, many researchers' procedures are still inconvenient for routine use with any specimen and a universal method has not been devised yet. In this review, some of the …

Characterization Of Rhizobium Sp. Isolated From Bean, Çi̇ğdem Küçük, Meri̇h Kivanç, Engi̇n Kinaci

Turkish Journal of Biology

Thirty nodule isolates from bean (Phaseolus vulgaris L.) grown in Eskişehir were studied for their physiological and biochemical characteristics. Most isolates produced abundant extracellular polysaccharides, tolerated high salt concentration (5% NaCl), grew at a temperature of 42 °C, and synthesized melanin. They were able to grow at pHs ranging from 3.5 to 9.0. The majority of the isolates showed an intrinsic resistance to the antibiotics chloramphenicol (20 and 50 µg ml^{-1}), erythromycin (30 µg ml^{-1}), kanamycin (10 µg ml^{-1}), and streptomycin (40, 80, and 100 µg ml^{-1}). Plasmid DNA profiles of the isolates were identified and it was determined that …

Evidence For The Presence Of A Second Electron Donor For The Cytoplasmic Thioredoxins In The Yeast Saccharomyces Cerevisiae, Ahmet Koç, Hüseyi̇n Ç. Karakaya, Ercan S. Ünlü

Turkish Journal of Biology

In yeast, the cytoplasmic thioredoxin system is composed of NADPH, thioredoxin reductase-1 (TRR1) and 2 thioredoxin genes (TRX1, TRX2). In this study, using yeast knockout mutants for TRR1, TRX1 and TRX2 genes, the role of the thioredoxin system in methionine sulfoxide reduction was investigated. Cells lacking both TRX1 and TRX2 genes simultaneously were not able to reduce methionine sulfoxides to methionine; however, mutants missing the TRR1 gene were able to reduce methionine sulfoxides to methionine, which showed that electrons could be transferred from NADPH to thioredoxins in the absence of TRR1. Similar results were observed for 3-phosphoadenosine 5-phosphosulfate reduction in …

The Effect Of Ferrum (Feso_4) On Culture Mushroom: Pleurotus Ostreatus (Jacq.) Kumm., Abdunnasir Yildiz, Ömer Faruk Yeşi̇l

Turkish Journal of Biology

This study was conducted on the growth, ratio of protein and cultivation of Pleurotus ostreatus on local celluosic wastes in different concentrations of the ferrous (Fe^{++}). It was observed that Fe^{++} had effect on the formation and growth of the basidiocarps. The shortest and longest period of basidiocarps formation and growth were obtained in 100 ppm and 300 ppm Fe^{++}, respectively. The higher total amount of yield was found for 100 ppm Fe^{++} when compared with control, 200 and 300 ppm Fe^{++}. Significant (P < 0.05) difference was found between the control and 100 ppm Fe^{++}, but the best yield was obtained. Mushroom protein ratio of all concentrations of ferrous (Fe^{++}) were found to be lower than control.

Synthesising Life-Sciences And Control Engineering: An Outline Survey And A Practical Example, Aidan O'Dwyer

Conference papers

There is an increasing interest in life science related areas in the electrical and control engineering community [1]. One manifestation of this interest is the development of interdisciplinary programmes, such as the B.Sc. in Medical Physics and Bioengineering, offered by the Dublin Institute of Technology from September 2005. A significant amount of research work in control engineering has focused on aspects of human physiological system, for example blood glucose regulation [2], cardiovascular modelling and control [3], and limb control [4]. There is an increasing emphasis on interdisciplinary research; in recognition of this, the Institute of Electrical Engineers (IEE) has starting …

The History Of Seafood In Irish Cuisine And Culture, Mairtin Mac Con Iomaire

Conference papers

Fish is one of the most abundant wild foods available to a small island nation. Certain species of seafood have moved from being ‘poor man’s food’ to ‘luxury food’ over time. It may be said that the Irish do not behave as island people since we have little or no history of exploiting the sea compared to our European partners. Ireland was late developing its fishing industry and now suffers reduced EU fish quotas, the unfortunate but necessary result of decades of over-fishing on European waters. This paper investigates the historical role seafood has played in Irish cuisine and culture …

Taking A Bite Out Of Hypertrophic Cardiomyopathy: Soy Diet And Disease, Cathy J. Hatcher, Craig T. Basson

PCOM Scholarly Works

Some forms of hypertrophic cardiomyopathy (HCM) are caused by mutations in cardiac sarcomeric genes, but environmental factors are believed to influence the hypertrophic response. A highly variable but potentially significant environmental factor is diet. Since soy-rich diets have been speculated to confer protection against cardiovascular disease, Stauffer et al. have explored the influence of a soy diet on cardiac growth and function in a transgenic mouse model of HCM (see the related article beginning on page 209). They report that mice fed a soy diet exhibited significantly worse HCM than mice fed a soy-free (milk protein) diet. This study provides …

Physical Fitness Of Children With Motor Learning Difficulties, Beth P. Hands, Dawne Larkin

Health Sciences Papers and Journal Articles

Children with motor learning difficulties (MLD) tend to be less physically active than their coordinated peers and one likely consequence is a reduced level of physical fitness. In this study, 52 children with MLD aged 5 to 8 years, were compared to 52 age- and gender-matched control children across a range of health and skill related fitness components. Analyses of variance revealed significantly lower scores in the group with MLD on the tests for cardiorespiratory endurance, flexibility, abdominal strength, speed, and power than the control group. Furthermore, the group with MLD had a significantly higher Body Mass Index (BMI). These …

The Use Of Genomewide Enu Mutagenesis Screens To Unravel Complex Mammalian Traits: Identifying Genes That Regulate Organ-Specific And Systemic Autoimmunity, Gerard F. Hoyne, Christopher C. Goodnow

Health Sciences Papers and Journal Articles

T-cell development is perhaps one of the best understood processes of mammalian cell differentiation, as many of the genes and pathways have been identified. By contrast, relatively little is known about the genes and pathways involved in immunological tolerance to self-antigens. Here, we describe the challenges associated with a genomewide screen designed at identifying new immune regulatory genes that uses a model of organ-specific autoimmunity leading to type 1 diabetes. The successful propagation and identification of the new gene variants will shed light on the various developmental checkpoints in lymphocyte development that are crucial for establishing tolerance to self-antigens.

Vitrification And Dehydration For The Preservation Of Gametes, Allison E. Moisan

LSU Doctoral Dissertations

Of the 36 species of felines in the world, all except the domestic cat are listed as endangered or threatened. To preserve the genetic diversity of felines and other species, genome resource banks have been established. Due to limited availability of germ cells for research, studies must use models to optimize the techniques before they are applied to endangered species. In this study, preservation of oocytes and spermatozoa was examined using the bovine as a model for felines. In the first series of experiments, bovine and feline oocytes were dehydrated, vitrified, warmed and cultured to assess their ability to undergo …

Self-Determination In Injury Rehabilitation: Designing A Climate For Promoting Adherence, Ryan Mark Green

LSU Doctoral Dissertations

The purpose of this dissertation was to use self-determination as a theoretical framework to investigate factors that influence college athletes’ adherence to injury rehabilitation programs. A two-part study, quantitative and qualitative approaches were used to gain insight into athletes’ motivation and decisions that they make regarding their engagement in injury rehabilitation. The focus of the quantitative study was to investigate the relationships between personal autonomy, levels of self-determination, perceived autonomy support, and perceived competence in injury rehabilitation. Participants (N=193 college athletes) completed surveys in a retrospective design. Autonomy orientations were positively related to higher levels of self-determination and the perception …

Physical Activity Behavior Of University Students: An Ecological Approach, Lisa Gaye Johnson

LSU Doctoral Dissertations

Despite the health benefits associated with active lifestyles, a majority of adults do not engage in sufficient levels of physical activity (PA). Few individual-focused interventions have produced sustained changes in PA behavior. Therefore, public health officials are promoting the use of ecological approaches to examine the multidimensional factors that influence choices about PA and other health behaviors. National statistics are mirrored in college populations, with one-half of students in the US failing to meet current PA recommendations and one-third classified as either overweight or obese. In light of this, increasing PA and obesity prevention have been identified as the top …