Organisms Commons^™

Development Of Oral Vaccines Against Lyme Disease, Rita Raquel Dos Anjos De Carvalho E Melo

Theses and Dissertations (ETD)

Lyme Disease, caused by the spirochete Borrelia burgdorferi, is the most common vector-borne disease in the United States and Europe. If left untreated, it can lead to permanent damage to the nervous and musculoskeletal systems. In some cases, patients that receive the recommended antibiotic therapy develop a debilitating health condition associated with substantial health care costs. Despite current preventive measures, the incidence and the geographic distribution of Lyme Disease continues to increase. Recent estimates from CDC suggest that the true number of cases of Lyme Disease in the US is approximately 300,000 per year. Yet, there is currently no vaccine …

Genetic Control Of Survival And Weight Loss During Pneumonic Burkholderia Pseudomallei (Bp) Infection, Felicia D. Emery

Theses and Dissertations (ETD)

Burkholderia pseudomallei (Bp) is a saprophytic, gram-negative aerobe and the causative agent of the disease melioidosis. Melioidosis is an infectious disease that occurs in humans and animals and is prevalent in Southeast Asia, northern Australia and other tropical areas. Transmission occurs through direct contact with the organism via ingestion, inhalation, or through open wounds and skin abrasions. Clinical presentation is extremely variable and can range from acute septicemia with bacterial dissemination to distant sites, to an isolated pulmonary infection. Treatment of melioidosis can be problematic because it is often difficult to diagnose and Bp is resistant to a diverse group …

Erg11-Mediated Azole Resistance In Candida Albicans, Stephanie Ann Flowers

Theses and Dissertations (ETD)

Although many medically important Candida species are commensal to the gut or colonizers of the skin, these organisms have the propensity to cause disease in the event of a waning immune system. Clinical manifestations of infections with Candida species can range from superficial mucosal infections to deep organ involvement usually resulting from haematogenous spread of infection. Despite significant progress made in the management of patients with fungal infections, the emergence of antifungal resistant clinical isolates creates significant problem in regards to antifungal prophylaxis and empirical treatment strategies. Antifungal resistance is associated with high mortality rates and hefty medical costs. The …

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 …

Interactions Of Francisella Tularensis With Components Of The Host Fibrinolytic System, Shawn Russell Clinton

Theses and Dissertations (ETD)

Francisella tularensis (FT) is a Gram-negative coccobacillus and causative agent of a life-threatening disease commonly referred to as tularemia. Due to the highly infectious nature of the organism, its previous development as a biowarfare agent and its potential use in acts of bioterrorism, this bacterium is listed as a Category A select agent by the Centers for Disease Control and Prevention (CDC). Efforts to understand the pathogenic mechanisms of FT within the host environment are vital for the development of safe and effective vaccines, as well as treatments, against tularemia. Though considered an intracellular pathogen, FT research of late has …

Transcriptional Regulation Of Azole Antifungal Resistance And Tolerance In Candida Glabrata, Kelly E. Caudle

Theses and Dissertations (ETD)

Azole antifungal resistance has emerged as a significant problem in the management of infections caused by fungi including Candida species. In recent years, Candida glabrata has become the second most common cause of mucosal and invasive fungal infections in humans second to Candida albicans. Not only are systemic C. glabrata infections characterized by high mortality rates, treatment failures to the azole class of antifungals, the most widely used antifungal for treatment of Candida infections, have been reported. Contributing to this problem, C. glabrata exhibits intrinsic reduced susceptibility to the azole antifungals, and the development of high-level azole resistance …

Transcriptional Regulation Of Azole Antifungal Resistance In Candida Albicans, Teresa T. Liu

Theses and Dissertations (ETD)

Candida albicans is a pathogenic fungi found in the mucosa, gastrointestinal, and urogenital tracts of humans. Oropharyngeal candidiasis (OPC), an opportunistic mucosal infection caused by C. albicans, occurs most frequently in patients infected with human immunodeficiency virus (HIV). OPC is usually treated with azole antifungals, a class of antifungals that target ergosterol biosynthesis, at low doses over long periods of time. This course of treatment allows for the development of azole resistance.

Two major mechanisms of azole resistance exist in C. albicans, the up-regulation of genes encoding efflux pumps and the up-regulation of ERG11, a gene encoding the azole drug …

Biochemical And Immunological Mechanisms Underlying Differential Interaction Of Superantigens With Host Immunogenetic Factors In Streptococcal Sepsis, Mohammed Nooh

Theses and Dissertations (ETD)

Group A streptococci (GAS) are serious human pathogens that can cause a wide array of diseases ranging from pharyngitis to streptococcal toxic shock (STSS), which is caused by excessive cytokines responses triggered by streptococcal superantigens (Strep SAgs). SAgs interact simultaneously with HLA class II molecules on antigen presenting cells (APC) and with the T cell receptor beta chain variable elements (TCR V) and cause excessive stimulation of both cell types and massive release of inflammatory mediators.

The Strep SAgs include the streptococcal pyrogenic exotoxins (Spes), which play a crucial role in the pathogenesis of severe invasive streptococcal diseases, including Strep …