Organisms Commons^™

Detection And Quantification Of Bacterial Species Important To Mental And Physical Health, David G. Leonard

Theses and Dissertations

The human gut microbiome contains an abundance of microorganisms which could influence mental health as well as physical health. These microorganisms produce chemicals which affect the brain and the body in various ways. Probiotic bacteria and yeasts have been studied to determine effects they have on mice, rats, and humans to illustrate the importance these microorganisms on health. Studies have shown that adding beneficial microorganisms to the human diet can have positive effects on mental and physical health, to include lessening symptoms of depression and anxiety, lessen gastrointestinal inflammation, displacing pathogens, and improving immunomodulatory response. A quantitative way to identify …

Chrysin‐Loaded Chitosan Nanoparticles Potentiates Antibiofilm Activity Against Staphylococcus Aureus, Busi Siddhardha, Uday Pandey, K. Kaviyarasu, Rajasekharreddy Pala, Asad Syed, Ali K. Bahkali, Abdallah M. Elgorban

Pharmacy Faculty Articles and Research

The application of nanotechnology in medicine is gaining popularity due to its ability to increase the bioavailability and biosorption of numerous drugs. Chrysin, a flavone constituent of Orocylumineicum vent is well‐reported for its biological properties. However, its therapeutic potential has not been fully exploited due to its poor solubility and bioavailability. In the present study, chrysin was encapsulated into chitosan nanoparticles using TPP as a linker. The nanoparticles were characterized and investigated for their anti‐biofilm activity against Staphylococcus aureus. At sub‐Minimum Inhibitory Concentration, the nanoparticles exhibited enhanced anti‐biofilm efficacy against S. aureus as compared to its bulk counterparts, chrysin …

Immune-Endocrine Links To Gregariousness In Wild House Mice, Patricia C. Lopes, Esther H. D. Carlitz, Morgan Kindel, Barbara König

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Social interactions are critically important for survival and impact overall-health, but also impose costs on animals, such as exposure to contagious agents. The immune system can play a critical role in modulating social behavior when animals are sick, as has been demonstrated within the context of “sickness behaviors.” Can immune molecules affect or be affected by social interactions even when animals are not sick, therefore serving a role in mediating pathogen exposure? We tested whether markers of immune function in both the blood and the brain are associated with gregariousness, quantified as number of animals interacted with per day. To …

Lavender Aromatherapy: Ready For Prime-Time Office Use?, Dennis J. Baumgardner

Journal of Patient-Centered Research and Reviews

The editor-in-chief of Journal of Patient-Centered Research and Reviews comments on the perioperative use of lavender aromatherapy and its potential to relieve pain and anxiety during minor primary care office procedures.

Prevalence Of The Hypervirulent Nap1/Bi/027 Strain Of C. Difficile In Southwestern Virginia And Risk Factors Associated With Infection, Andrew O. Hanna, Anthony Baffoe-Bonnie, Shikha Vasudeva

Graduate Medical Education (GME) Resident and Fellow Research Day Posters

C. difficile infection (CDI) incidence has increased over the last several decades. The BI/NAP1/027 ribotype was discovered in 2005 and has since been responsible for multiple outbreaks in the US and Canada. This subtype of C. Difficile is known to be more virulent in vivo and produce more severe disease. Limited regional data of the prevalence of this ribotype is available, which could help guide treatment. Using infection control data from a large regional hospital and a VA medical center, this study documented the prevalence of the 027 ribotype in Southwest Virginia. Patients were included if they were tested at …

Characterization Of The Gonococcal Calprotectin Zn-Acquisition System, Tdfh, And The Efficacy Of Metal Starvation For Treating Gonococcal Disease, Michael T. Kammerman

Theses and Dissertations

Abstract

Characterization of the Gonococcal Calprotectin Zn-Acquisition System, TdfH, and the Efficacy of Metal Starvation for Treating Gonococcal Disease.

By Michael T. Kammerman, B.S.

A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University

Virginia Commonwealth University, 2020

Major Director: Cynthia Nau Cornelissen, Ph.D.

Professor, Department of Microbiology and Immunology

Neisseria gonorrhoeae, the bacterial agent that is responsible for the human disease gonorrhea, has had a steady increase in the number of infections per year. In 2018 the WHO estimated over 87 million infections occurred world-wide, and the CDC …

Prediction Of The Vaginal Microbiome Using Urine Samples, Christopher R. Diachok

Theses and Dissertations

The vaginal microbiome is associated with women’s health, including but not limited to the pathogenesis of bacterial vaginosis, adverse pregnancy outcomes including preterm birth and sexually transmitted infections. However, there has been very limited research on the urinary microbiome and its relationship to the vaginal microbiome. We sought to predict the vaginal microbiome profile using clean catch urine samples from the same person. Here, paired vaginal and urine samples were collected and sequenced by 16S ribosomal RNA sequencing. Alpha and beta diversity analysis showed that there was no significant difference between the paired vaginal and urine microbiomes. In fact, a …

Effects Of (R,S)-Ketamine And (2r,6r)-Hydroxynorketamine: A Preclinical Study, Remington Rice

Theses and Dissertations

In 2017, 7.1% of US adults were diagnosed with depression, and 50% of patients received medication to treat their depression. Depression can cause severe interruptions in an individual's cognitive functioning and behaviors like sleeping, eating, working, and socializing. Unfortunately, approximately 40% of patients do not respond to treatment with monoaminergic medications (e.g. Prozac) and therapeutic effects may be delayed 2-8 weeks. Due to these therapeutic shortcomings, faster acting and more efficacious treatments are needed. Recent preclinical findings indicate potential for glutamatergic drugs like (R,S)-ketamine and (2R,6R) hydroxynorketamine to produce more rapid and longer-acting therapeutic effects. The antidepressant effectiveness of (R,S)-ketamine …

Characterization Of The Physical And Chemical Effect Of Membrane Disruption And Protein Inhibiting Treatments On E. Coli, Khadijah Wright

Honors Undergraduate Theses

The increase in antibacterial resistance has placed the issue of microbial multi-drug resistance on a global stage (Gurunathan, 2019). This issue poses a threat to human and animal health as well as to the environment (Aslam et al., 2018). It affects not only the efficacy of treatment but also how those treatments are conducted (Friedman, Temkin, & Carmeli, 2016). As a result of this ongoing threat, new treatments that have potent effects on bacteria are necessary. One scientific response to this issue has been the development of multifunctional nanoparticles (NPs)(H. Wang et al., 2018). NPs have the ability to be …

Assessing Morphology Of Iprgcs After Traumatic Brain Injury, Brian Foresi, Matt Smith

Williams Honors College, Honors Research Projects

ipRGCs are retinal ganglion cells that project to visual processing centers of the brain for nonimage forming visual functions. The relation of ipRGCs to tramatic brain injury (TBI) is emerging as data has been published describing ipRGC functional changes in TBI affected military veterans. Major symptomologies of concussions, a mild form of TBI, also overlap with the function governed by sites in the brain with major ipRGC projection percentages. Assesing if a morphological change is occuring in the ipRGCs after a TBI could support the idea of a pathological mechanism of the injury. This study could also indicate further relevance …

Structural Biology Of The Enterovirus Replication-Linked 5'-Cloverleaf Rna And Associated Virus Proteins, Steven M. Pascal, Ravindranath Garimella, Meghan S. Warden, Komala Ponniah

Chemistry & Biochemistry Faculty Publications

Although enteroviruses are associated with a wide variety of diseases and conditions, their mode of replication is well conserved. Their genome is carried as a single, positive-sense RNA strand. At the 5′ end of the strand is an approximately 90-nucleotide self-complementary region called the 5′ cloverleaf, or the oriL. This noncoding region serves as a platform upon which host and virus proteins, including the 3B, 3C, and 3D virus proteins, assemble in order to initiate replication of a negative-sense RNA strand. The negative strand in turn serves as a template for synthesis of multiple positive-sense RNA strands. Building on structural …

The Role Of Manganese In Streptococcus Sanguinis, Tanya M. Puccio

Theses and Dissertations

Streptococcus sanguinis is primarily associated with oral health as a commensal bacterium. As an opportunistic pathogen, S. sanguinis is capable of colonizing heart valve vegetations, leading to the disease infective endocarditis. Previous studies from our lab have identified the high-affinity manganese transporter SsaACB as important for endocarditis virulence. The impact that manganese depletion has on S. sanguinis had never been evaluated and a secondary manganese transporter has not been identified. Thus, we employed the use of a fermentor to control large-scale growth over time and depleted manganese in an ΔssaACB mutant using a metal chelator, EDTA. The changes in …

Extensively Drug-Resistant Pseudomonas Aeruginosa In Vitro Susceptibility And Mechanisms Of Resistance, Chanah Gallagher

Theses and Dissertations--Pharmacy

Pseudomonas aeruginosa causes severe healthcare-associated infections. Forty-eight extensively drug-resistant (XDR)-P. aeruginosa isolates were selected from 287 isolates collected for evaluation based on clinical susceptibility data. In vitro activity of commonly utilized antimicrobials (i.e. antipseudomonal beta-lactams, aminoglycosides, fluoroquinolones, and polymyxins) plus ceftolozane-tazobactam, ceftazidime-avibactam, and aztreonam-avibactam against XDR-P. aeruginosa were determined. The mechanism of resistance profile was determined through phenotypic expression analysis. Overall, polymyxin B and colistin were 100% susceptible. Apart from the polymyxins, ceftolozane-tazobactam had the highest susceptibility (94%) followed by ceftazidime-avibactam (90%) and amikacin (83%). Ceftolozane-tazobactam activity was not significantly different from ceftazidime-avibactam (p=0.6831). Only 40% of isolates …

Novel Small Molecule Antifungals For Invasive Fungal Infections, Emily Dennis

Theses and Dissertations--Pharmacy

Human fungal pathogens cause a range of diseases from benign skin conditions (i.e., ringworm) to thrush, mucosal membrane infections, and life-threatening systemic infections including bloodstream infections (i.e., aspergillosis and candidiasis) and Cryptococcal meningitis. These systemic infections occur most often in immunocompromised individuals and have high mortality rates. Current antifungal agents used in the clinic belong to three main classes: the polyenes (e.g., amphotericin B (AmB)), the echinocandins (e.g., caspofungin (CFG)), and the azoles (e.g., fluconazole (FLC)). In addition, the antimetabolite pyrimidine analogue flucytosine is used in combination with AmB. The …

Antifungal Defense Molecules From Bacterial Symbionts Of North American Trachymyrmex Ants, Georgia Scherer

CMC Senior Theses

Defensive symbioses, in which microbes provide molecular defenses for an animal host, hold great potential as untapped sources of therapeutically useful antibiotics. Fungus-growing ants use antifungal defenses from bacterial symbionts to suppress pathogenic fungi in their nests. Preliminary chemical investigations of symbiotic bacteria from this large family of ants have uncovered novel antifungal molecules with therapeutic potential, such as dentigerumycin and selvamicin.

In this study, the bacterial symbionts of North American Trachymyrmex fungus-growing ants are investigated for antifungal molecules. Plate-based bioassays using ecologically-relevant fungal pathogens confirmed that these bacteria have antifungal activity. In order to purify and identify the antifungal …

Mapping Misinformation In The Coronavirus Outbreak, Ana Santos Rutschman

All Faculty Scholarship

The coronavirus outbreak has sent ripples of fear and confusion across the world. These sentiments—and our collective responses to the outbreak—are made worse by rampant misinformation surrounding the new strain of the virus, COVID-2019. In this post, I survey some of the most pervasive areas of tentacular coronavirus-related misinformation that has proliferated online -- as well as the responses of social media companies like YouTube, Facebook, Pinterest and TikTok that may ultimately prove inadequate given the magnitude of the problem.

Understanding The Host Immune Response Against Pseudomonas Aeruginosa To Develop Novel Therapeutics And Vaccines, Emel Sen Kilic

Graduate Theses, Dissertations, and Problem Reports

Pseudomonas aeruginosa is a Gram-negative opportunistic bacterium that causes a broad range of acute and chronic infections. The high adaptability and emergence of multidrug-resistant strains of this bacterium pose a significant threat to human health. Particularly, pneumonia caused by this pathogen is associated with high morbidity and mortality in immunocompromised patients. To prevent these infections, we aimed to develop novel vaccine strategies by characterizing the host immune response against P. aeruginosa. During respiratory infections, P. aeruginosa first contacts with epithelial cells along the respiratory tract. Using RNA-sequencing, we were able to characterize transcriptional changes of the epithelial cells in …

Neuroanatomy Of The Blackspotted Rockskipper, Entomacrodus Striatus, Pooja Dayal

Williams Honors College, Honors Research Projects

Here I characterized the central neuroanatomy of the Blackspotted Rockskipper, Entomacrodus striatus, native to French Polynesia. The neuroanatomy of E. striatus has not been studied prior to this paper. I used several histology and antibody staining techniques to accomplish this, including Crystal Violet, immunohistochemistry, immunofluorescence, and Bielschowsky’s Silver Nitrate staining. This paper describes the most successful techniques used, identifies major structures in the species’ neuroanatomy, and also explains why studying E. striatus is important in the future of vertebrate research.

Probiotics And The Prevention Of Clostridioides Difficile: A Review Of Existing Systematic Reviews, Andrea L. Onstad

All Graduate Theses, Dissertations, and Other Capstone Projects

Clostridioides difficile is the leading cause of infectious diarrhea (Vernaya et al., 2017). Probiotics have been proposed to provide a protective benefit against Clostridioides difficile infection (CDI). The objective of this literature review was to examine the research evidence pertaining to the use of probiotics for the prevention of CDI in individuals receiving antibiotic therapy. A systematic literature review of studies published between 2015 and 2019 was performed. Five databases were searched, which yielded 10 systematic reviews that met strict inclusion criteria. Overall, the majority of evidence indicated that probiotics versus no treatment, placebo, or usual care have the potential …

Tick-Borne Infections In New Hampshire: An Evaluation Of The Diagnostic Process In A Local Patient Population, Katherine Anderson

Honors Theses and Capstones

Overall, approximately 95 percent of reported cases of vector-borne disease were associated with ticks, making these the most medically important group of arthropods in the United States.¹ Despite the prevalence of tick-borne infections, the process for the diagnosis of this condition is not well studied. This study aims to analyze data from a pool of 100 patients who underwent testing for tick-borne disease in the same institution in Dover, New Hampshire during the most recent peak tick season of 2019. Information utilized in this study included: patient age, sex, location of testing (inpatient versus outpatient), diagnostic testing methods used …