Pharmacy and Pharmaceutical Sciences Commons^™

Pkpd-Model Based Preclinical Characterization Of The Activity Of Spectinamide 1599 Against Mycobacterial Subpopulations. And The Identification Of Potential Partners For Combination Therapy, Zaid Hanif Temrikar

Theses and Dissertations (ETD)

Tuberculosis is one of the top 10 causes of death worldwide and the leading cause of death from a single infectious agent prior to COVID19. Mycobacterium tuberculosis (Mtb) is the causative agent of TB. The interaction between Mtb and the immune system leads to development of diverse environmental niches and physiology within the lung of the TB patients. Mtb is thought to adapt and thrive in such an environment by transforming to different phenotypic variants. Such variants are difficult to kill and are thought to prolong TB pharmacotherapy. Spectinamide 1599 is a synthetic modification of spectinomycin that has demonstrated excellent …

Physiologically-Based Pharmacokinetic (Pbpk) Modeling For The Preclinical Development Of Spectinamide Antibiotics, Keyur R. Parmar

Theses and Dissertations (ETD)

Despite being an ancient disease caused by Mycobacterium tuberculosis (Mtb) and after decades of research, tuberculosis (TB) still affects millions of people every year worldwide. In 2018, the World Health Organization (WHO) reported that 10 million people developed tuberculosis and 1.5 million died of the disease. With the increase in the multidrug-resistant (MDR) and extensively drug-resistant (XDR) cases, the treatment for TB with the standard first and second-line therapy is becoming increasingly difficult. Therefore, there is an urgent need to find new anti-TB drugs as combination partners of existing and experimental classes of antimicrobial agents to shorten and simplify the …

Computer-Aided Drug Discovery For Helicobacter Pylori, Nicole Ann Vita

Theses and Dissertations (ETD)

Helicobacter pylori is a high-priority drug-resistant pathogen and is currently the only bacteria considered to be a class I carcinogen and there is a critical need to identify novel chemical matter to treat H. pylori infections. Hp is responsible for greater than 60% of gastric cancer related deaths and 89% of all gastric cancer morbidities. In a previous study, our lab identified novel Hp thienopyrmidine inhibitors that target respiratory complex I, an essential enzyme in respiration. Respiratory complex I is a large asymmetric multidomain and membrane bound enzyme and due to these innate features, it is not practical for biophysical …

Antibiotic Tolerance And Heteroresistance: Associated Fitness Costs And Potential In Evading Antibiotic Killing, Tina H. Dao

Theses and Dissertations (ETD)

Streptococcus pneumoniae is a prominent human pathogen that causes both invasive and non-invasive diseases, such as otitis media, pneumonia, meningitis, and bacteremia. Although it is frequently an asymptomatic colonizer of the human nasopharynx, S. pneumoniae is a major cause of morbidity and mortality in the immune compromised population, young children, and the elderly. Up until the 1970s, S. pneumoniae was susceptible to almost all antibiotics. Since then, this pathogen has gained resistance to a variety of antibiotic treatments, including beta-lactams, macrolides, and fluoroquinolones.

In the first chapter, we focused on fluoroquinolone resistance in S. pneumoniae. Fluoroquinolones are one of the …

Model-Based Dose-Exposure-Response Assessment For Lead And Backup Spectinamide In A Mouse Model Of Tuberculosis, Santosh Janardan Wagh

Theses and Dissertations (ETD)

Despite decades of research, tuberculosis remains the oldest pathogen-based disease that is the leading cause of death from a single infectious agent. Among many anti-tubercular therapies under investigation, the semisynthetic compounds spectinamides are a promising novel class of anti-tuberculosis agents. One such lead candidate, spectinamide 1810, and backup spectinamide 1599 have demonstrated excellent efficacy, safety, and drug-like properties in various in vitro and in vivo assessments. The dose-ranging and dose fractionation studies were designed to characterize the dose-exposure-response relationship for lead and backup spectinamide in a mouse model of Mycobacterium tuberculosis infection. In this current study, we used 26 and …

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 …

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 - …

Development And Evaluation Of Amphotericin B Loaded Iron Oxide Nanoparticles For Targeted Drug Delivery To Systemic Fungal Infections, Pavan Balabathula

Theses and Dissertations (ETD)

A targeted nanotheronostic drug delivery system to diagnose and treat life threatening invasive fungal infections (IFIs) such as cryptococcal meningitis was designed, developed, characterized, and evaluated. To address the development processes, first, iron oxide nanoparticles (IONP) (34-40 nm) coated with bovine serum albumin (BSA), loaded and targeted with amphotericin B (AMB) (AMB-IONP) was formulated by applying a layer by layer approach. Several designs (A, B, C, D, & E) of AMB-IONP were developed and their physicochemical properties such as drug loading with HPLC method, particle size, poly dispersity index (PDI), and ζ-potential using dynamic light scattering (DLS) technique, morphology with …

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 …

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 …

Pharmacokinetic And Pharmacodynamic Studies Of A Novel Spectinamide Series Of Antituberculosis Agents, V. N. R. Pavan Kumar Vaddady

Theses and Dissertations (ETD)

Spectinamides are novel amide derivatives of the antibiotic spectinomycin that have emerged as a new class of agents to treat tuberculosis. These agents showed potent in vitro activity against Mycobacterium tuberculosis (MTB) compared to spectinomycin and in a preliminary in vivo study in interferon gamma (IFN‑γ) knockout mice, spectinamide Lee1329 reduced the lung bacillary load of TB comparable to streptomycin. We hypothesized that the application of an iterative pharmacokinetics and pharmacodynamics (PK/PD) guided approach would facilitate the optimization of these lead compounds suitable for further development.

A series of in vitro experiments including parallel artificial membrane permeability assay (PAMPA), microsomal …

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 …