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Temperature Drives Epidemics In A Zooplankton-Fungus Disease System: A Trait-Driven Approach Points To Transmission Via Host Foraging, Marta S. Shocket, Alexander T. Strauss, Jessica L. Hite, Maja Šljivar, David J. Civitello, Meghan A. Duffy, Carla E. Cáceres, Spencer R. Hall

School of Biological Sciences: Faculty Publications

Climatic warming will likely have idiosyncratic impacts on infectious diseases, causing some to increase while others decrease or shift geographically. A mechanistic framework could better predict these different temperature-disease outcomes. However, such a framework remains challenging to develop, due to the nonlinear and (sometimes) opposing thermal responses of different host and parasite traits and due to the difficulty of validating model predictions with observations and experiments. We address these challenges in a zooplanktonfungus (Daphnia dentifera–Metschnikowia bicuspidata) system. We test the hypothesis that warmer temperatures promote disease spread and produce larger epidemics. In lakes, epidemics that start earlier and warmer in …

Acinetobacter Bacteriophage Discovery In Soil, Michael Plaskett

Rose-Hulman Undergraduate Research Publications

The Acinetobacter genus is home to a wide range of bacteria that are gram-negative, aerobic, non-motile, oxidase-negative, catalase positive, and coccobacilli with a G+C content of 39 to 47% (Bergogne-Berezin, 1996). These bacteria are universal as they reside in the soil, water, sewage, various surfaces; and are also able to infect humans; however, a majority of the infections are caused by the species Acinetobacter baumannii. This bacterium is the most prevalent etiological cause of the Acinetobacter infections due to it being a nosocomial infection or one that is acquired in a health care setting. The infections that occur in a …

Agrochemicals Increase Risk Of Human Schistosomiasis By Supporting Higher Densities Of Intermediate Hosts, Neal T. Halstead, Christopher M. Hoover, Arathi Arakala, David J. Civitello, Guilio A. De Leo, Manoj Gambhir, Steve A. Johnson, Nicolas Jouanard, Kristin A. Loerns, Karena Nguyen, Jason R. Rohr

Integrative Biology Faculty and Staff Publications

Schistosomiasis is a snail-borne parasitic disease that ranks among the most important water-based diseases of humans in developing countries. Increased prevalence and spread of human schistosomiasis to non-endemic areas has been consistently linked with water resource management related to agricultural expansion. However, the role of agrochemical pollution in human schistosome transmission remains unexplored, despite strong evidence of agrochemicals increasing snail-borne diseases of wildlife and a projected 2- to 5-fold increase in global agrochemical use by 2050. Using a field mesocosm experiment, we show that environmentally relevant concentrations of fertilizer, a herbicide, and an insecticide, individually and as mixtures, increase densities …

Experimental Evidence Of A Pathogen Invasion Threshold, Tad Dallas, Martin Krkošek, John M. Drake

Faculty Publications

Host density thresholds to pathogen invasion separate regions of parameter space corresponding to endemic and disease-free states. The host density threshold is a central concept in theoretical epidemiology and a common target of human and wildlife disease control programmes, but there is mixed evidence supporting the existence of thresholds, especially in wildlife populations or for pathogens with complex transmission modes (e.g. environmental transmission). Here, we demonstrate the existence of a host density threshold for an environmentally transmitted pathogen by combining an epidemiological model with a microcosm experiment. Experimental epidemics consisted of replicate populations of naive crustacean zooplankton (Daphnia dentifera …

Landscape Genomics: Natural Selection Drives The Evolution Of Mitogenome In Penguins, Barbara Ramos, Daniel González-Acuña, David Loyola, Warren Johnson, Patricia Parker, Melanie Massaro, Gisele Dantas, Marcelo Miranda, Juliana Vianna

Biology Department Faculty Works

BackgroundMitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. However, selection over mitochondrial DNA (mtDNA) genes has usually been evaluated at the population level. We sequenced by NGS 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distributed from the equator to Antarctica. Signatures of selection of 13 mitochondrial protein-coding genes were evaluated by comparing among species within and among genera (Spheniscus, Pygoscelis, Eudyptula, Eudyptes and …

Novel Role Of Histone Deacetylase 11 (Hdac11) In Regulating Normal And Malignant Hematopoiesis, Jie Chen

USF Tampa Graduate Theses and Dissertations

During hematopoiesis, multilineage progenitor cells and the precursors are committed to individual hematopoietic lineages. In normal myelopoiesis, the immature myeloid cells (IMCs) differentiate into macrophages, neutrophils or dendritic cells. However, under tumor burden, these IMCs differentiate into myeloid derived suppressor cells (MDSCs) result in an up-regulation of immune suppressive factors and pro-tumor effect. The development of normal or malignant is tightly controlled by endogenous signals such as transcription factors and epigenetic regulations. HDAC11 is the newest identified members of the histone deacetylase (HDAC) family. Previous study in our group had identified HDAC11 as a negative regulator of interleukin 10 (IL-10) …

Positioning Animal Welfare In The One Health Concept Through Evaluation Of An Animal Welfare Center In Skopje, Macedonia, Miroslav Radeski

Department of Biological Sciences Publications

The Animal Welfare Center (AWC) in Macedonia was established in 2009. The objectives of the center are animal welfare (AW) education, research, raising public awareness of AW, and increasing cooperation between the stakeholders. One Health (OH) was not the major focus of the AWC work initially, but, rather, a focus that evolved recently. The objective of this study was to evaluate the AWC from the OH perspective as an example case for positioning the AW within the overall OH concept. Three types of evaluation were performed: (1) assessment of OH-ness, by quantitative measurement of the operational and infrastructural aspects of …

Exosomes Serve As Novel Modes Of Tick-Borne Flavivirus Transmission From Arthropod To Human Cells And Facilitates Dissemination Of Viral Rna And Proteins To The Vertebrate Neuronal Cells, Wenshuo Zhou, Michael Woodson, Biswas Neupane, Fengwei Bai, Michael B. Sherman, Kyung H. Choi, Girish Neelakanta, Hameeda Sultana

Faculty Publications

Molecular determinants and mechanisms of arthropod-borne flavivirus transmission to the vertebrate host are poorly understood. In this study, we show for the first time that a cell line from medically important arthropods, such as ticks, secretes extracellular vesicles (EVs) including exosomes that mediate transmission of flavivirus RNA and proteins to the human cells. Our study shows that tick-borne Langat virus (LGTV), a model pathogen closely related to tick-borne encephalitis virus (TBEV), profusely uses arthropod exosomes for transmission of viral RNA and proteins to the human- skin keratinocytes and blood endothelial cells. Cryo-electron microscopy showed the presence of purified arthropod/neuronal exosomes …

Conjugative Transposons And Their Cargo Genes Vary Across Natural Populations Of Rickettsia Buchneri Infecting The Tick Ixodes Scapularis, Rachael Hagen, Victoria I. Verhoeve, Joseph J. Gillespie, Timothy P. Driscoll

Faculty & Staff Scholarship

Rickettsia buchneri (formerly Rickettsia endosymbiont of Ixodes scapularis, or REIS) is an obligate intracellular endoparasite of the black-legged tick, the primary vector of Lyme disease in North America. It is noteworthy among the rickettsiae for its relatively large genome (1.8 Mb) and extraordinary proliferation of mobile genetic elements (MGEs), which comprise nearly 35% of its genome. Previous analysis of the R. buchneri genome identified several integrative conjugative elements named Rickettsiales amplified genomic elements (RAGEs); the composition of these RAGEs suggests that continued genomic invasions by MGEs facilitated the proliferation of rickettsial genes related to an intracellular lifestyle. In this study, …

Repeated Translocation Of A Gene Cassette Drives Sex-Chromosome Turnover In Strawberries, Jacob A. Tennessen, Na Wei, Shannon C.K. Straub, Rajanikanth Govindarajulu, Aaron Liston, Tia-Lynn Ashman

Faculty & Staff Scholarship

Turnovers of sex-determining systems represent important diversifying forces across eukary- otes. Shifts in sex chromosomes—but conservation of the master sex-determining genes— characterize distantly related animal lineages. Yet in plants, in which separate sexes have evolved repeatedly and sex chromosomes are typically homomorphic, we do not know whether such translocations drive sex-chromosome turnovers within closely related taxo- nomic groups. This phenomenon can only be demonstrated by identifying sex-associated nucleotide sequences, still largely unknown in plants. The wild North American octoploid strawberries (Fragaria) exhibit separate sexes (dioecy) with homomorphic, female heteroga- metic (ZW) inheritance, yet sex maps to three different chromosomes in …

Genetic Assessment Of Inbred Chicken Lines Indicates Genomic Signatures Of Resistance To Marek's Disease, Lingyang Xu, Yanghua He, George E. Liu, Huanmin Zhang, Hans H. Cheng, Robert L. Taylor Jr, Jiuzhou Song

Faculty & Staff Scholarship

Background: Marek’s disease (MD) is a highly contagious pathogenic and oncogenic disease primarily affecting chickens. However, the mechanisms of genetic resistance for MD are complex and not fully understood. MD-resistant line 63 and MD-susceptible line 72 are two highly inbred progenitor lines of White Leghorn. Recombinant Congenic Strains (RCS) were developed from these two lines, which show varied susceptibility to MD.

Results: We investigated genetic structure and genomic signatures across the genome, including the line 63 and line 72, six RCSs, and two reciprocally crossed flocks between the lines 63 and 72 (F1 63 × 72 and F1 72 × …

Monitoring Ohio Bat Communities And Populations Using Mobile Acoustics, Molly C. Simonis

Browse all Theses and Dissertations

The goal of my thesis is to: 1) provide baseline information of where Ohio bats are foraging in Wright State University's (WSU) campus woods in relation to forest age and habitat (Chapter 1), 2) determine potential roost availability for local bats (Chapter 1), and 3) examine changes in state-wide species composition following the introduction of White-nose Syndrome (WNS; Chapter 2). In Chapter 1, I created walking bat acoustic routes and used generalized linear models to determine what forest ages and habitats had the greatest bat activity in the WSU campus woods. I conducted habitat transects throughout all forest ages to …

Sequestered Alkaloid Defenses In The Dendrobatid Poison Frog Oophaga Pumilio Provide Variable Protection From Microbial Pathogens, K. J. Hovey, E. M. Seiter, Erin E. Johnson, Ralph Saporito

2018 Faculty Bibliography

Most amphibians produce their own defensive chemicals; however, poison frogs sequester their alkaloid-based defenses from dietary arthropods. Alkaloids function as a defense against predators, and certain types appear to inhibit microbial growth. Alkaloid defenses vary considerably among populations of poison frogs, reflecting geographic differences in availability of dietary arthropods. Consequently, environmentally driven differences in frog defenses may have significant implications regarding their protection against pathogens. While natural alkaloid mixtures in dendrobatid poison frogs have recently been shown to inhibit growth of non-pathogenic microbes, no studies have examined the effectiveness of alkaloids against microbes that infect these frogs. Herein, we examined …

Identification Of Novel Mites (Miniature Inverted-Repeat Transposable Elements) In Coxiella Burnetii: Implications For Protein And Small Rna Evolution, Shaun Wachter, Rahul Raghavan, Jenny Wachter, Michael F. Minnick

Biological Sciences Faculty Publications

Background: Coxiella burnetii is a Gram-negative gammaproteobacterium and zoonotic agent of Q fever. C. burnetii’s genome contains an abundance of pseudogenes and numerous selfish genetic elements. MITEs (miniature invertedrepeat transposable elements) are non-autonomous transposons that occur in all domains of life and are thought to be insertion sequences (ISs) that have lost their transposase function. Like most transposable elements (TEs), MITEs are thought to play an active role in evolution by altering gene function and expression through insertion and deletion activities. However, information regarding bacterial MITEs is limited.

Results: We describe two MITE families discovered during research on small non-coding …

Ms Environmental Biology Capstone Project, Annamaria Marcel

Regis University Student Publications (comprehensive collection)

Due to the worldwide decline of biodiversity, protected nature reserves are necessary for species facing extinction. Many frog species have been experiencing rapid population decline and extinction due to the threat of the fungus Batrachochytrium dendrobatidis (Bd), which inflicts the highly transmittable and deadly disease chytridiomycosis. Chytridiomycosis causes increased skin tissue growth which disrupts respiration and the maintenance of water balance, which can ultimately lead to death. Certain ecological and geographical characteristics have been studied in order to assess their influence on Bd’s prevalence. Specifically, it is hypothesized that high elevations, lotic habitats, and low species richness have a positive …

The Naked Mole Rat Possesses A Differently Phased Core Clock System Along With A Different Glucose Handling And Mtor Systems Compared To The Common Lab Mouse, Soumyaditya Ghosh

ETD Archive

INTRODUCTION The Naked Mole Rat [ Heterocephalus glaber] is a type of rodent -with the highest average lifespan-30 years-among all the rodent species. It lives underground in sealed burrow systems with little to no exposure to day-night transitions on the surface. It shows polyphasic round the clock activity within its subterranean burrow system. The activity and physiology of most animals are governed by the biological circadian clock. The biological circadian clock is a system that oscillates with a rough periodicity of 24 hours. Environmental zeitgebers regulate the entrainment of the circadian clock to the 24-hour day-night cycle and light is …

Modeling The Disappearance Of The Neanderthals Using Concepts Of Population Dynamics And Ecology, Michael F. Roberts, Stephen E. Bricher

Faculty Publications

Current hypotheses regarding the disappearance of Neanderthals (NEA) in Europe fall into two main categories: climate change, and competition. Here we review current research and existing mathematical models that deal with this question, and we propose an approach that incorporates and permits the investigation of the current hypotheses. We have developed a set of differential equations that model population dynamics of anatomically modern humans (AMH) and NEA, their ecological relations to prey species, and their mutual interactions. The model allows investigators to explore each of the two main categories or combinations of both, as well as various forms of competition …

Investigation Into The Role Of Manganese In The Growth Of The Opportunistic Pathogen Streptococcus Sanguinis, Brittany Spivey

AUCTUS: The Journal of Undergraduate Research and Creative Scholarship

While Streptococcus sanguinis plays a beneficial role in the oral cavity as a competitor of Streptococcus mutans and Streptococcus sobrinus, the bacteria that produce dental caries, it can cause deadly infective endocarditis if given the opportunity to colonize the vegetations that form over damaged endocardial tissue. Pre-existing heart conditions, surgery, and intravenous drug use predispose individuals to endocarditis. S. sanguinis growth and consequential virulence is significantly impeded by restriction to manganese. This is due to the resulting overwhelming oxidative stress and formation of reactive oxygen species which damage DNA and other cellular components. Manganese is essential for S. sanguinis proteins …

The Contributions Of Fc Gamma Receptors And Macropinocytosis To The Internalization, Sorting And Clearance Of Antibody Coated Nanovesicles In Macrophages, George Opoku-Kusi Jr.

Electronic Theses and Dissertations

Macrophages are tissue-resident phagocytes that play critical roles in immune response and tissue homeostasis. They have a tremendous capacity to internalize objects of various sizes ranging from nanoscale viral particles to micron sized bacteria and tumor cells. This phenomenon, termed phagocytosis for the uptake of large particles, or endocytosis for the uptake of small particles, is integral to the immune response in multicellular organisms. Macrophages express FcγRs, which are tyrosine kinase receptors that bind IgG on an opsonized target. Binding of IgG Fc domain to the extracellular domain of an FcγR triggers signaling cascades that coordinate internalization of the opsonized …

Identification Of Macropinocytosis Regulating Proteins And Signaling From Macropinosomes, Louise Monga

Electronic Theses and Dissertations

Understanding macrophage cell biology is important due to macrophages key roles in human health and diseases including proper immune function, wound healing, atherosclerosis, and cancer. Despite their importance, relatively little is understood about macrophage activation, growth factor signaling, and cytoskeletal regulation. This thesis presents data from investigations into mechanisms of macrophage growth factor signaling and actin polymerization for ruffling and macropinocytosis. Alt-R CRISPR-Cas9 method and dextran uptake assay were used to knock out individual genes (SHP-1, Lyn, Syk, BTK, Vav1) and determine their role in macropinocytosis and CSF-1R signaling. Dextran uptake was disrupted in SHP-1 and Lyn targeted knockout cells, …

Vector Competence Of Northern California Mosquitoes For Dirofilaria Immitis (Spirurida: Onchocercidae), Rebekah Lynn Dian

University of the Pacific Theses and Dissertations

Dirofilaria immitis, commonly known as dog heartworm, is a dangerous filarial nematode that is transmitted by a mosquito vector. Although this parasite is historically localized to regions closer to the equator, the last few decades have experienced an increase in the amount of dog heartworm cases in Northern California, most notably in Lake and San Joaquin Counties. The primary vector of D. immitis in Northern California is Aedes sierrensis, but it is not prevalent enough in some counties to explain the increase in infections. Because of this, more prevalent and abundant species should be assessed for their ability to transmit …

Treatment Of Hiv-Infected Individuals With The Histone Deacetylase Inhibitor Panobinostat Results In Increased Numbers Of Regulatory T Cells And Limits Ex Vivo Lipopolysaccharide-Induced Inflammatory Responses, Christel Rothe Brinkmann, Jesper Falkesgaard Højen, Thomas Aagaard Rasmussen, Anne Sofie Kjær, Rikke Olesen, Paul W. Denton, Lars Østergaard, Zhengyu Ouyang, Mathias Lichterfeld, Xu Yu, Ole Schmeltz Søgaard, Charles Dinarello, Martin Tolstrup

Biology Faculty Publications

Histone deacetylase inhibitors (HDACi) modulate the transcriptional activity of all cells, including innate and adaptive immune cells. Therefore, we aimed to evaluate immunological effects of treatment with the HDACi panobinostat in HIV-infected patients during a clinical phase IIa latency reversal trial. Using flow cytometry, we investigated changes in T cell activation (CD69, CD38, HLA-DR) and the expression of CD39 and CTLA4 on regulatory T cells (Tregs). Whole-blood stimulations were performed and cytokine responses measured using Luminex. Gene expression in purified peripheral blood mononuclear cells (PBMCs) was evaluated using an Affymetrix HTA 2.0 gene chip. We found that proportions of CD4+ …

The Dissemination, Regulatory Role, And Evolution Of Mycobacterial Inteins, Danielle Skye Kelley

Legacy Theses & Dissertations (2009 - 2024)

Inteins are intervening protein elements, capable of coordinating escape from a host protein through a self-catalyzed mechanism, called protein splicing. This results in free intein and a mature host protein product. Inteins are also mobile elements and many contain homing endonucleases that enable the targeting to ectopic sites and invasion of novel niches. Inteins have been found across all three domains of life and are often present in replication, recombination, and repair proteins. However, it is unclear if the observed distribution is simply a factor of endonuclease preference or if inteins have been selectively maintained due to an adaptation that …

Surveillance Of South Dakota Mosquito Abundance, Infection Rate, And Insecticide Susceptibility, Geoffrey P. Vincent

Electronic Theses and Dissertations

The aim of this dissertation was to survey and evaluate the abundance, infection rate, and insecticide susceptibility of mosquito fauna present in South Dakota. Mosquito surveillance has been conducted across South Dakota to record and track potential West Nile virus (WNV) vectors from 2004 to 2017. The nuisance mosquito Aedes vexans was found to be the most abundant species overall in the state and most abundant in many of the regions. The WNV vector, Culex tarsalis, was found to be the second most abundant mosquito and the most abundant vector mosquito across the state. However, geospatial variation did exist between …

Detection Of Cyanotoxins (Microcystins/Nodularins) In Hepatic Tissues And Epidermal Mats Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Northeast Florida, Amber Brown

UNF Graduate Theses and Dissertations

The St. Johns River (SJR; Jacksonville, FL, USA) is a large, brackish, estuarine system characterized by considerable anthropogenic pollution, recurrent harmful algal blooms (HABs), and diverse toxin-producing cyanobacteria. The most prevalent toxins in SJR water samples are microcystins/nodularins (MCs/NODs). Additionally, the SJR provides critical habitat for a genetically and behaviorally distinct estuarine community of bottlenose dolphins (Tursiops truncatus) that routinely uses and strands in low mesohaline and oligohaline areas of the river. This population has been subject to two unusual mortality events (UME) since 2010 and has since been described as having substantial declines in population health, characterized …

Establishing Relationships Among Environmental Stressors, Host Immune Status, And Wasting Disease Susceptibility In The Dominant Seagrass Species Thalassia Testudinum, Paige Joy Duffin

UNF Graduate Theses and Dissertations

A growing body of evidence supports the observation that marine disease outbreaks, especially those caused by opportunistic pathogens, are increasing in frequency and severity. One genus of such pathogens, Labyrinthula, has been identified as the causative agent of seagrass wasting disease, an epidemic that has historically plagued seagrass beds around the world. It is suspected that pathogenicity is intimately linked to the ability of the host to initiate defense responses, but a lack of compelling evidence prevents any meaningful application of preliminary observations. This body of work investigated the roles of host genotype, host immune status, and environmental stressors …

Distribution Of Porcine Endogenous Retrovirus (Perv) Variants In Domestic And Feral Pigs, Rashmi Acharya

Master's Theses or Doctor of Nursing Practice

Xenotransplantation is considered an alternative to allotransplantation to relieve the current shortage of human organs. Due to their similar size and physiology, the organs of pigs are of particular interest for this purpose. Endogenous retroviruses are a result of integration of retroviral genomes into the genome of infected germ cells as DNA copies (proviruses), which are then carried in all cells of the offspring of the organism. Porcine Endogenous Retroviruses (PERVs) are of special concern because they are found in pig organs and tissue that might be used for xenotransplantation. PERV proviruses, already incorporated into the pig’s genome, can be …

Identification And Characterization Of Tri-Colored Bat Hibernaculum In Russell County, Kansas, Angelica Sprague

Master's Theses or Doctor of Nursing Practice

Caves are often essential during hibernation, a sensitive stage in the life cycle of bats. Caves offer more stable conditions, such as temperature and relative humidity, during the changing seasons when food supply is limited, and weather is unstable. As caves in North-Central Kansas are sparse, the hibernating status of tri-colored bat (Perimyotis subflavus) is not well known. Bats are experiencing substantial population declines within the United States, caused primarily by white nose-syndrome, as well as habitat loss and degradation, and increased wind-power facilities. In the winter seasons of 2015 and 2016, I studied tri-colored bat hibernacula. A man-made “cave” …

Characterizing Borrelia Burgdorferi In Virginia : Lyme Disease Prevalence As A Matter Of Bacterial Genetic Variation, Hannah Cornman

Honors Theses

yme Disease (LD) incidence and spatial distribution has grown dramatically in the past 20 years. In Virginia, the growth has been especially drastic, primarily in the Western part of the state. This research project investigates how genetic variability of the Lyme Disease causing bacteria, Borrelia burgdorferi, might be contributing to this increase in LD incidence in western Virginia. To do this, B. burgdorferi samples were isolated from ticks found across the state and were characterized by multilocus sequence typing (MLST). Phylogenetic and minimum spanning tree analyses were also performed. It was hypothesized that the increasing number of Lyme disease infections …

Range Expansion And The Origin Of Usa300 North American Epidemic Methicillin-Resistant Staphylococcus Aureus, Lavanya Challagundla, Isabella A. Tickler, Xavier Didelot, David C. Coleman, Anna C. Shore, Geoffrey W. Coombs, Daniel O. Sordelli, Eric L. Brown, Robert Skov, Anders Rhod Larsen, Jinnethe Reyes, Iraida E. Robledo, Guillermo J. Vazquez, Paul Rivera, Paul D. Fey, Kurt Stevenson, Shu-Hua Wang, Barry N. Kreiswirth, Jose R. Mediavilla, Cesar A. Arias, Paul J. Planet, Rathel L. Nolan, Fred C. Tenover, Richard V. Goering, D. Ashley Robinson

Biology Faculty Publications

The USA300 North American epidemic (USA300-NAE) clone of methicillin-resistant Staphylococcus aureus has caused a wave of severe skin and soft tissue infections in the United States since it emerged in the early 2000s, but its geographic origin is obscure. Here we use the population genomic signatures expected from the serial founder effects of a geographic range expansion to infer the origin of USA300-NAE and identify polymorphisms associated with its spread. Genome sequences from 357 isolates from 22 U.S. states and territories and seven other countries are compared. We observe two significant signatures of range expansion, including decreases in genetic diversity …