Organisms Commons^™

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …

The Use Of Probiotics To Prevent Ventilator-Associated Pneumonia In Adults, Michael Roper, Paige Douthett

Physician Assistant Capstones, 2016 to 2019

Objective: To assess the efficacy and safety of preventing the acquisition of ventilator- associated pneumonia with the use of probiotic supplementation, as compared to a placebo, among hospitalized adult men and women receiving more than 24 hours of mechanical ventilation. Design: Systematic Literature Review. Methods: Systematic searches were conducted through PubMed and Scopus using the search terms “ventilator”, “probiotics”, and “prevention”. Records were excluded from the analysis if they were published before 2015, full text was not available, studies other than randomized control trial or cohort studies, and if the study population was less than 18 years old. Results: Of …

Plasticity In The Human Gut Microbiome Defies Evolutionary Constraints, Andres Gomez, Ashok Kumar Sharma, Elizabeth K. Mallott, Klara J. Petrzelkova, Carolyn A. Jost Robinson, Carl J. Yeoman, Franck Carbonero, Barbora Pafco, Jessica M. Rothman, Alexander Ulanov, Klara Vickova, Katherine R. Amato, Stephanie L. Schnorr, Nathaniel J. Dominy, David Modry, Angelique Todd, Manolito Torralba, Karen E. Nelson, Michael B. Burns, Ran Blekhman, Melissa Remis, Rebecca M. Stumpf, Brenda A. Wilson, H. Rex Gaskins, Paul A. Garber, Bryan A. White, Steven R. Leigh

Anthropology Faculty Research

The gut microbiome of primates, including humans, is reported to closely follow host evolutionary history, with gut microbiome composition being specific to the genetic background of its primate host. However, the comparative models used to date have mainly included a limited set of closely related primates. To further understand the forces that shape the primate gut microbiome, with reference to human populations, we expanded the comparative analysis of variation among gut microbiome compositions and their primate hosts, including 9 different primate species and 4 human groups characterized by a diverse set of subsistence patterns (n = 448 samples). The results …

Infection Potential Of Rickettsia Felis Via Ingestion, Matthew M. Schexnayder

LSU Master's Theses

Rickettsia felis is the etiologic agent of flea-borne spotted fever (FBSF) in humans and a poorly described cause of fever in animals. It is transmitted by its primary arthropod vector and reservoir host, the cat flea Ctenocephalides felis. Known routes of Rickettsia felis transmission between Rickettsia felis-infected cat fleas and vertebrate hosts include cutaneous bites and contamination of cutaneous wounds with infective flea feces. The bulk of FBSF infections occur in young children in Africa, though infections of people at all ages all over the world have been confirmed. As mammals and young children frequently come into contact …

Anti-Crispr Vs. Crispr: The Evolutionary Arms Race Between Microorganisms, Rachael M. St. Jacques

Masters Theses, 2010-2019

CRISPR arrays are a defense mechanism employed by bacteria against viral invaders. Cas proteins do the work in detecting, capturing, and integrating the viral DNA into the CRISPR array (Barrangou et al., 2007). Anti-CRISPR proteins are produced by phages, viruses that infect bacteria, to stop the bacterial host’s CRISPR-Cas complex from interrupting the phage life cycle (Bondy-Denomy, et al., 2015).

SEA-PHAGES is a course-based bacteriophage research network composed of 120 colleges and known at James Madison University as Viral Discovery. JMU uses the unsequenced Streptomyces griseus ATCC10137 as a host for bacteriophage discovery and propagation, and in this study we …

Investigation Of The In Vitro Interactions Between Two Common Cystic Fibrosis Pathogens, Staphylococcus Aureus And Stenotrophomonas Maltophilia., Matthew Hill

College of Arts & Sciences Senior Honors Theses

Cystic Fibrosis (CF) is one of the most common autosomal disorders in Caucasian populations. This disorder creates a very opportune environment for many pathogens within the patient’s lung. Two common pathogens that infect CF patient’s lungs are Staphylococcus aureusand Stenotrophomonas maltophilia. These two species of bacteria can colonize host environments and establish mats of cells known as biofilms that become very difficult to eradicate with antibiotics. Once inside a CF lung, these pathogens must not only evade the host immune response but they also interact and compete with each other; however, how bacterial pathogens interact inside the host lung …

Effects Of Ambient And Laser Light On Water Evaporation From The Surface Of Polyurethane Swabs Doped With Surfactant, Collin Campbell

Chemical Engineering Undergraduate Honors Theses

Polyurethane swabs are a common instrument for environmental sampling in the food, medical, and forensic fields due to their high recovery of organisms like viruses, spores, and bacteria. For sampling microbes in food and medical facilities, storage of the collected samples occurs under the absence of light to promote growth for more accurate testing. In the forensic fields, microbial growth results in sample contamination so the inhibition of this growth requires the drying of the swabs. This work studies the evaporation rates of water from polyurethane swabs under zero watt incident light, 30 W fluorescent bulb, 50 mW 532 nm …

Ultramicrobacteria Genome Database Project, Abdullah A. Salim, Tien Tran, Andrew Putt, Terry C. Hazen

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Ultramicrobacteria (UMB) are a largely uncultured, globally abundant, and metabolically active group of bacteria. UMB have cell diameters ≤0.3μm, cell volumes ≤0.1 μm3, and small streamlined genomes. Recent findings indicate that UMB aid in bioremediation and nutrient cycling, but future investigations and comprehension of current findings are skewed by highly variable nomenclature and a lack of databases for functional, genomic, geochemical, or spatial data specific to candidate UMB. We aim to develop a user-friendly open-access database of various UMB candidates linked to an open-access online map where researchers can gather genomic, spatial, and geochemical data. Our comprehensive review of literature …

Human Gut Microbiome, Enrico José Aveiro Johannsen, Mandy Peak

Posters

The human gut microbiome has been an area of interest for researchers due to its established link with human metabolism, nutrition, physiology, and immune functions. The research presented further investigates the microbiome to better understand it. Stools from two healthy young African males and a French obese individual were analyzed using MALDI-TOF MS and the enrichment culture technique. For the identification of bacterial species metagenomics, genomics, and culturomics were used. The results showed a much broader biodiversity in the human gut than previously predicted, as well as better results when using culturomics for measuring biodiversity in large-scale isolation.

The Effects Of Bacterial Endotoxin Lps On Synaptic Transmission At The Neuromuscular Junction, Robin L. Cooper, Micaiah Mcnabb, Jeremy Nadolski

Biology Faculty Publications

The direct action of bacterial lipopolysaccharides (LPS) endotoxin was shown to enhance synaptic transmission and hyperpolarize the membrane potential at low doses, but block glutamatergic receptors and decrease observable spontaneous events at a high dosage. The dosage effects are LPS type specific. The hyperpolarization is not due to voltage-gated potassium channels or to activation of nitric oxide synthase (NOS). The effects are induced directly by LPS, independent of an immune response.

Spore Forming Actinobacterial Diversity Of Cholistan Desert Pakistan: Polyphasic Taxonomy, Antimicrobial Potential And Chemical Profiling, Adeela Fatima, Usman Aftab, Khaled A. Shaaban, Jon S. Thorson, Imran Sajid

Center for Pharmaceutical Research and Innovation Faculty Publications

Background: Actinobacteria are famous for the production of unique secondary metabolites that help in controlling the continuously emerging drug resistance all over the globe. This study aimed at the investigation of an extreme environment the Cholistan desert, located in southern Punjab, Pakistan, for actinobacterial diversity and their activity against methicillin resistant Staphylococcus aureus (MRSA). The Cholistan desert is a sub-tropical and arid ecosystem with harsh environment, limited rainfall and low humidity. The 20 soil and sand samples were collected from different locations in the desert and the actinobacterial strains were selectively isolated. The isolated strains were identified using a polyphasic …

Spatial-Temporal Variability Of In Situ Cyanobacteria Vertical Structure In Western Lake Erie: Implications For Remote Sensing Observations, Karl Bosse, Michael Sayers, Robert Shuchman, Gary L. Fahnenstiel, Steven A. Ruberg, David L. Fanslow, Dack G. Stuart, Thomas H. Johengen, Ashley M. Burtner

Michigan Tech Publications

Remote sensing has provided expanded temporal and spatial range to the study of harmful algal blooms (cyanoHABs) in western Lake Erie, allowing for a greater understanding of bloom dynamics than is possible through in situ sampling. However, satellites are limited in their ability to specifically target cyanobacteria and can only observe the water within the first optical depth. This limits the ability of remote sensing to make conclusions about full water column cyanoHAB biomass if cyanobacteria are vertically stratified. FluoroProbe data were collected at nine stations across western Lake Erie in 2015 and 2016 and analyzed to characterize spatio-temporal variability …

Severity Of Disease And Mortality For Hospitalized Patients With Community-Acquired Viral Pneumonia Compared To Patients With Community-Acquired Bacterial Pneumonia, Richard Y. Kim, Thomas Chandler, Stephen P. Furmanek, Timothy Lee Wiemken, Rodrigo Cavallazzi

The University of Louisville Journal of Respiratory Infections

Background: There exists a large body of literature to help identify, diagnose, treat, and manage community-acquired pneumonia (CAP). Despite this, there is little data that directly compares the clinical syndromes and complications of pure bacterial pneumonia to pure viral pneumonia. Our study compares the clinical presentation, morbidity and mortality of viral vs. bacterial etiologies of CAP.

Methods: This was a secondary data analysis of the Community-Acquired Pneumonia Organization (CAPO) international study database. Data was collected concerning patient demographics, physical examination findings, laboratory findings, radiological findings, severity of illness, and clinical outcomes and stratified according to the two study groups, CAVP …

Characterization Of Immunomodulatory Microbial Factors In Medicinal Plants, Kriti Kalpana

Dissertations, Theses, and Capstone Projects

Medicinal plants are one of the biggest sources of natural products with therapeutic importance. There are currently over 28,000 plants with putative medicinal values. Plant-derived compounds have been explored extensively for various biological activities ranging from anti-cancer, immune-boosting to anti-inflammatory and anti-oxidant. Some of the most important therapeutic agents are of plant-origin, such as paclitaxel from Pacific yew (Taxus brevifolia) and artemisinin from qinghao su (a Chinese medicinal herb; a.k.a. Artemisia annua) to name a few.

The study presented in this thesis started out as classical pharmacognosy research, which focused on the identification of immunostimulatory factors in …

Examination Of Strain-Dependent Differences In S. Sanguinis Virulence And Growth, Shannon Baker

Theses and Dissertations

Streptococcus sanguinis, an abundant and benign inhabitant of the oral cavity, is an important etiologic agent of infective endocarditis, particularly in people with pre-disposing cardiac valvular damage. Although commonly isolated from patients with IE, little is known about the factors that make any particular S. sanguinis isolate more virulent than another or, indeed, whether significant differences in virulence exist among isolates. To investigate the virulence of multiple isolates, a variation of the Bar-seq (barcode sequencing) method was employed. A conserved chromosomal site was identified for subsequent insertion of a barcode identifier, unique for each strain. Barcode insertion did not …

Adaptation Of The Streptococcal Collagen-Like Protein 1, Scl1, Of Group A Streptococcus To Recognize Fibronectin Type Iii Repeats, Dudley H. Mcnitt

Graduate Theses, Dissertations, and Problem Reports

Background: Group A Streptococcus (GAS) is responsible more than 700 million infections worldwide each year. Most of these infections start with initial colonization of the throat and skin, which is augmented by surface adhesins. The streptococcal collagen-like protein 1 (Scl1) is a major adhesin expressed by GAS that contains an N-terminal sequence-variable (V) domain, protruded away from the cell surface by the collagen domain. The Scl-V domain is comprised of three pairs of anti-parallel α-helices interconnected by surface-exposed loops. For attachment, GAS adhesins require a portal of entry, such as a wound or breach in the epithelium, to enter …

Pyocyanin, A Virulence Factor Produced By Sepsis-Causing Pseudomonas Aeruginosa, Promotes Adipose Wasting And Cachexia, Nika Larian

Theses and Dissertations--Pharmacology and Nutritional Sciences

Sepsis is a leading cause of death among critically ill patients that results in metabolic alterations including hypercatabolism, lipoatrophy, and muscle wasting, contributing to the development of cachexia. Septic cachexia is associated with loss of body weight, fat mass, and lean mass and dysregulated immune function. There are currently no efficacious treatment strategies for septic cachexia, and nutritional interventions have limited success in preventing hypercatabolic wasting. Pyocyanin is a virulence factor produced by sepsis-causing Pseudomonas aeruginosa that has been shown to activate the aryl hydrocarbon receptor (AhR), increase inflammation, and produce reactive oxygen species. Thus, pyocyanin represents a novel mechanistic …