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Full-Text Articles in Organisms

Erg11-Mediated Azole Resistance In Candida Albicans, Stephanie Ann Flowers Dec 2013

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 Dec 2013

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 …


Regulating Rsma Expression In Pseudomonas Aeruginosa, Sean D. Stacey Aug 2013

Regulating Rsma Expression In Pseudomonas Aeruginosa, Sean D. Stacey

Electronic Theses and Dissertations

Pseudomonas aeruginosa, a Gram-negative bacillus, commonly infects immunocompromised individuals and uses a variety of virulence factors to persist in these hosts. The posttranscriptional regulator, RsmA, plays a role in the expression of many virulence factors in P. aeruginosa. RsmA up regulates virulence factors used in colonizing hosts. However, regulation of rsmA is not well elucidated. Transposon mutagenesis was performed on P. aeruginosa containing a transcriptional rsmA-lacZ fusion to answer this question. Mutants were screened via β-galactosidase assay and transposon insertions identified via arbitrary PCR. A probable MFS transporter, we named mtpX, was one significant transposon mutant identified. …


Effects Of Clostridium Difficile On The Human Immune Response, Mike Mcgovern Apr 2013

Effects Of Clostridium Difficile On The Human Immune Response, Mike Mcgovern

Honors Projects in Science and Technology

Clostridium difficile is a bacterium that is rapidly becoming a large issue in the medical community due to its tendency to infect hospital patients and its resistance to antibiotics. By studying the way in which the pathogen interacts with the human immune system, it is possible to better understand how the body naturally fights off the disease. This knowledge can allow medical professionals to develop treatments that can help curtail the infection before serious symptoms occur. Working under a grant program alongside Professors Kirsten Hokeness and Chris Reid, I was able to research the effects that exposure to the C. …


Pseudomonas Aeruginosa Ampr Transcriptional Regulatory Network, Deepak Balasubramanian Mar 2013

Pseudomonas Aeruginosa Ampr Transcriptional Regulatory Network, Deepak Balasubramanian

FIU Electronic Theses and Dissertations

In Enterobacteriaceae, the transcriptional regulator AmpR, a member of the LysR family, regulates the expression of a chromosomal β-lactamase AmpC. The regulatory repertoire of AmpR is broader in Pseudomonas aeruginosa, an opportunistic pathogen responsible for numerous acute and chronic infections including cystic fibrosis. Previous studies showed that in addition to regulating ampC, P. aeruginosa AmpR regulates the sigma factor AlgT/U and production of some quorum sensing (QS)-regulated virulence factors. In order to better understand the ampR regulon, the transcriptional profiles generated using DNA microarrays and RNA-Seq of the prototypic P. aeruginosa PAO1 strain with its isogenic ampR deletion …


Systematic Assessment Of The Contribution Of Superantigens To Nasopharyngeal Colonization In A Mouse Model Of Streptococcal Infection, Katherine J. Kasper Jan 2013

Systematic Assessment Of The Contribution Of Superantigens To Nasopharyngeal Colonization In A Mouse Model Of Streptococcal Infection, Katherine J. Kasper

Electronic Thesis and Dissertation Repository

Streptococcus pyogenes is adapted for persistence in humans. It typically colonizes the tonsils and skin, and humans are the only known reservoir. S. pyogenes can cause a wide range of mild to serious infections. Most streptococci-related deaths are due to complications of rheumatic fever and invasive infections. S. pyogenes produces virulence factors that contribute to the pathogen’s ability to colonize and cause disease, including streptococcal superantigens (SAgs), also known as streptococcal pyrogenic exotoxins (Spes). SAgs function by cross-linking T cells and antigen presenting cells (APC) which may cause a massive inflammatory response, and as such have been found to contribute …