Bacterial Infections and Mycoses Commons^™

Intravaginal Cooling Provides Symptom Relief In Women With Vulvovaginal Candidiasis And Reduces Immunopathology In An Accompanying Mouse Model, Junko Yano, Kimberly Langdon, Michael Swor, Mairi C. Noverr, Paul L. Fidel

School of Dentistry Faculty Publications

BACKGROUND: Vulvovaginal candidiasis (VVC), caused primarily by Candida albicans, is currently treated with either prescription or over-the-counter antifungal drugs, often with variable efficacy and relapses. New and improved therapeutic strategies, including drug-free treatment alternatives, are needed. Upon overgrowth or environmental triggers, C. albicans yeast transitions into hyphae that results in an aberrant immunopathologic response by neutrophils, contributing to the characteristic vulvovaginal symptoms. The purpose of this study was to evaluate the efficacy of a patented intravaginal cooling device (Vlisse®) to provide symptom relief in women with VVC via putative reversal of C. albicans hyphae to the commensal yeast form, with …

Impaired Neutrophil Extracellular Trap-Forming Capacity Contributes To Susceptibility To Chronic Vaginitis In A Mouse Model Of Vulvovaginal Candidiasis, Junko Yano, Paul L. Fidel

School of Dentistry Faculty Publications

Vulvovaginal candidiasis (VVC), caused by is characterized by aberrant inflammation by polymorphonuclear neutrophils (PMNs) in the vaginal lumen. Data from the established murine model shows that despite potent antifungal properties, PMNs fail to clear due to local heparan sulfate that inhibits the interaction between PMNs and , resulting in chronic vaginal immunopathology. To understand the role of neutrophil extracellular traps (NETs) in defense against at the vaginal mucosa, we investigated the NET-forming capacity of PMNs in chronic VVC-susceptible (CVVC-S/C3H) and -resistant (CVVC-R/CD-1) mouse strains. Immunofluorescence revealed the formation of NETs (release of DNA with PMN-derived antimicrobial proteins) in PMN cocultures …

Examining How Non-Antifungal Medications Impact Host-Fungal Interactions, Parker Ryan Reitler

Theses and Dissertations (ETD)

Invasive fungal infections (IFIs) are estimated to kill 1.5 million people each year with mortality rates remaining high (around 30-70%), despite the availability of three major classes of antifungal drugs. Furthermore, millions more suffer debilitating infections of the mucosal membranes or destructive subcutaneous mycoses. One of the most common IFIs is invasive candidiasis, mostly commonly caused by Candida albicans infections, with mortality rates of approximately 30%. In addition, the population of susceptible individuals and the incidences of both mucosal and systemic mycoses continue to rise due to the widespread use of broad-spectrum antibacterial agents, cancer chemotherapies, and the immune suppressive …

The Impact Of Candida Albicans Glycogen On Fitness, Virulence And Host Response, Jian Miao

Theses and Dissertations (ETD)

Candida albicans is an opportunistic human fungal pathogen that presents in healthy persons colonizing the oropharyngeal, esophageal, and gastrointestinal mucosa. This polymorphic fungal pathogen remains a leading cause of both invasive and superficial mycoses. C. albicans can cause oropharyngeal candidiasis (OPC) and disseminated candidiasis when normal host immunity is disturbed, while also causing vulvovaginal candidiasis (VVC) in healthy women. Adaptation to different host niches requires rapid and coordinated changes in Candida metabolism and physiology to cope with host immune surveillance and to counteract host-imposed constraints such as glucose limitation. Although largely unexplored in C. albicans, the glycogen metabolism pathway is …

Tiny But Mighty, An Exploration Of Microbes And Plants As Sources Of Small Novel Bioactive Compounds Against Invasive Mycoses., Hannah Mai Peacock, James Anthony O'Connor

SURE Journal: Science Undergraduate Research Experience Journal

Despite the high mortality rate involved with invasive cerebral mycoses, there is a relative lack of research available around antifungals capable of crossing the blood brain barrier.

In this study the metabolites of four plants (Crocus vernus, Miniature Narcissus (daffodil), Osmanthus delavayi and Taraxacum officinale (common dandelion)) and two bacteria (Lacticaseibacillus paracasei and Staphylococcus epidermidis) were extracted and assayed for antifungal activity against Candida albicans and Saccharomyces cerevisiae. Thin layer chromatography and bioautography were then employed to assess the activity of the constituent components of sources showing antifungal activity.

Metabolites of S.epidermidis, and extracts …

Sensing Surfaces: A Non-Filamentous C. Albicans Response, Elias Smith

Theses/Capstones/Creative Projects

Resulting infections of mucosal tissues by Candida albicans present difficulty in treatment due to the formation of biofilms and invasion of tissue directed by thigmo-tropic responses of hyphal cells. Initiation of biofilm formation, however, is largely dependent on yeast-form cells. Their ability to sense surfaces, however, has yet to be examined. In the present study, an initial genetic profiling of the surface sensing response by non-filamentous Candida albicans was generated. In order to assess the ability for yeast-form C. albicans cells to recognize surfaces, four differentially solidified YPD plate types were created using agar, noble agar, Gelrite, and carrageenan. Genetic …

Validation And Application Of A Novel Target-Based Whole-Cell Screen To Identify Antifungal Compounds, Christian Alexander Dejarnette

Theses and Dissertations (ETD)

Traditional approaches to drug discovery are inefficient and have several key limitations that constrain our capacity to rapidly identify and develop novel experimental therapeutics. To address this, we have devised a second-generation target-based whole-cell screening assay based on the principles of competitive fitness, which can rapidly identify target-specific and physiologically-active compounds. Briefly, strains expressing high, intermediate, and low levels of a preselected target protein were constructed, tagged with spectrally distinct fluorescent proteins (FPs), and mixed together. The pooled strains were then grown in the presence of various small molecules, and the relative growth of each strain within the mixed culture …

The Effects Of Farnesol, A Quorum Sensing Molecule From Candida Albicans, On Alcaligenes Faecalis, Savannah Hutson

Undergraduate Honors Theses

Quorum sensing molecules have become a recent focus of study to learn if and how they can be used, both on their own and in conjecture with current antimicrobial methods, as a means of bacterial control. One such quorum sensing molecule is the sesquiterpene alcohol, Farnesol, which is synthesized and released by the fungus, Candida albicans. In most in-vivo cases, our laboratory has shown that Alcaligenes faecalis overtakes C. albicans, preventing its growth. However, as a way to counteract this inhibitory effect, Farnesol may be one way that Candida has found to fight back. In this study, we …

Investigation Of Novel Virulence Mechanisms In Candida Albicans, Elisa Marie Tafoya Vesely

Dissertations and Theses (Open Access)

Candida albicans is the most important fungal species associated with humans. Normally present in the human microbiome as a commensal colonizer, C. albicans is also the fourth most prevalent organism isolated from bloodstream infections in hospitals. Disseminated infections have an associated mortality rate of around 40%. The results of the work described in this dissertation cover the broad subject of C. albicans adaptation to the host and the mechanisms by which this organism is able to survive and cause infection through a variety of means. A key determinant in disease progression is interaction with innate immune cells, specifically macrophages and …

Novel Determinants That Influence Azole Susceptibility In Candida Glabrata And Candida Albicans, Sarah Garland Whaley

Theses and Dissertations (ETD)

Despite the scientific and medical communities’ best efforts, the incidence of fungal infections in susceptible populations continues to rise. The most common cause of these opportunistic fungal infections is Candida. In fact, Candida is the fourth most common pathogen associated with nosocomial blood stream infections. Reported mortality rates for patients with candidemia vary, but have not decreased in the past fifteen years and are reported to be as high as 50%. Candida glabrata, second only to Candida albicans among Candida infections, expresses high rates of resistance to treatment with arguably the best class of currently available antifungals - …

Filamentous Fungal Carbon Catabolite Repression Supports Metabolic Plasticity And Stress Responses Essential For Disease Progression, Sarah R. Beattie, Kenneth Mark, Arsa Thammahong, Laure Nicolas Annick Ries, Sourabh Dhingra, Alayna Caffrey-Carr, Chao Cheng

Dartmouth Scholarship

Aspergillus fumigatus is responsible for a disproportionate number of invasive mycosis cases relative to other common filamentous fungi. While many fungal factors critical for infection establishment are known, genes essential for disease persistence and progression are ill defined. We propose that fungal factors that promote navigation of the rapidly changing nutrient and structural landscape characteristic of disease progression represent untapped clinically relevant therapeutic targets. To this end, we find that A. fumigatus requires a carbon catabolite repression (CCR) mediated genetic network to support in vivo fungal fitness and disease progression. While CCR as mediated by the transcriptional repressor CreA is …

Identification Of Transcription Factors Gzf3, Rfx1, Orf19.3928 As Being Implicated In Candida-Bacterial Interactions., Joni Watson

Undergraduate Honors Theses

Candida albicans is an opportunistic pathogen that is present in the normal flora in a majority of individuals. One key factor in C. albicans virulence is the ability to change its morphology from yeast to an elongated or hyphal form. The regulation of this morphogenesis relies in part upon quorum sensing (QS) molecules. C. albicans often exists as part of a mixed culture alongside other microbes and is influenced by their presence as well as the presence of QS molecules that they produce. In this study, a library of diploid homozygous transcriptional regulator knockout (TRKO) mutants were screened to identify …

Signal Transduction And Transcriptional Regulation Pathways Essential For Azole Resistance In Candida Albicans, Erin M. Vasicek

Theses and Dissertations (ETD)

Candida albicans is the most prevalent human fungal pathogen, found as a commensal organism in the mucosa, gastrointestinal, and urogenital tracts of humans. This pathogenic fungus causes a wide spectrum of diseases, including the mucosal infection oropharyngeal candidiasis (OPC) which frequently effects patients with human immunodeficiency virus (HIV). The azole antifungals (such as fluconazole) are the most widely used and important ergosterol biosynthesis inhibitors (EBIs) for the treatment of Candida infections, including OPC. However, the azoles are fungistatic against C. albicans and therefore have limited efficacy against this organism, especially for immunocompromised patients. In C. albicans, the transcription factor Upc2 …

Analysis Of The Cyc1 Promoter In Candida Albicans, Tomica Blocker

McCabe Thesis Collection

Scientists are considering two factors that may be important in the pathogenesis of C. albicans', it's capability to morph from yeast to hyphal phase, and its differences in colony morphology, cell shape, cell surface and cell permeability. (5) Unfortunately, unlike the bacteria, yeasts do not yet have proven virulence factors. However, science is suggesting that some of the major factors which contribute to the virulence of Candida are its ability to form hyphae, its ability to resist phagocytosis, its ability to adhere to epithelial cell surfaces, its ability to grow well at 37 degrees Celsius, and its ability to secrete …