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Electroporation-mediated locoregional delivery of FLT3L-based immunotherapy promotes anticancer immunity
No full textDendritic cells (DCs) are a unique group of immune cells that can orchestrate antigen-specific immunity against cancer cells. However, DC functions are often compromised within the tumor microenvironment (TME) due to the inherent immunosuppressive signals. There is a potential to enhance cytotoxic T cell response against cancer malignancies by manipulating DCs to overcome this hurdle. One approach is to administer Fms-like tyrosine kinase receptor 3 ligand (Flt3L), a vitally important cytokine for DC expansion and differentiation. In this study, the electroporation-mediated delivery of a novel albumin-fused Flt3L DNA (alb-Flt3L DNA) was tested to induce an antitumor immune response. Our findings demonstrated that this albumin fusion construct exhibits prolonged bioactivity in targeted tissues. Also, alb-Flt3L administration to TC-1-bearing-C57BL/6 mice led to better tumor control and superior survival. Immunological analysis revealed that alb- Flt3L DNA administration promoted robust cDC1 expansion in the blood, lymph node, and tumor. There was an increased level of IFN-γ-secreting CD8+ lymphocytes associated with the greater cDC1 population. Altogether, our data presents a novel DC-based immunotherapy via a DNA construct to promote an antitumor effect
CT TO POINT CLOUD FUSION FOR AUTONOMOUS ROBOTIC TUMOR RESECTION
Get PDFIn order to track the location of tumors during surgery, information from the
preoperative CT scans is used to determine the location of the tumor. How ever, as the surgeon operates, the tumor may be deformed which presents
a major hurdle for accurately resecting the tumor, and can lead to surgical
inaccuracy, increased operation time, and excessive margins. This issue is par ticularly pronounced in robot-assisted partial nephrectomy (RAPN), where
the kidney undergoes significant deformations during operation. Toward
addressing this, we introduce a novel occupancy network-based method for
the localization of tumors within kidney phantoms undergoing deformations
at interactive speeds. We validate our method by introducing a 3D hydrogel
kidney phantom embedded with exophytic and endophytic renal tumors. It
closely mimics real tissue mechanics to simulate kidney deformation during
in vivo surgery, providing excellent contrast and clear delineation of tumor
margins to enable automatic threshold-based segmentation. Our findings in dicate that the proposed method can localize tumors in moderately deforming
kidneys with a margin of 10mm to 12mm, while providing essential volumet ric 3D information at over 60Hz. This capability directly enables downstream
tasks such as robotic resection
Essays in Applied Microeconomics
Get PDFThese essays study policy questions using the tools of empirical microeconomics. Chapter one studies how governments should design policies to integrate private and public markets for health insurance. Chapter two quantifies the marginal labor supply disincentives of welfare. Chapter three documents the profile of individuals that adopted self-protective health behaviors during the Covid-19 pandemic.
Chapter one develops and implements a framework that captures how health insurance firms endogenously choose which markets to enter and products to offer. These decisions depend on government policies and how consumers will sort into and utilize healthcare within an insurance plan based on their health status and elasticity of healthcare consumption. I use this model to simulate the effects of an alternate policy that is able to generate similar levels of firm participation and enrollment in the private insurance market while lowering government spending by approximately 6\%.
Chapter two reexamines the literature on the impact of welfare on labor supply by incorporating more general forms of unobserved heterogeneity into consumer preferences for welfare participation and labor supply. We estimate the marginal labor supply response to changes in welfare using state-level variation in barriers to welfare participation. We then use these estimates to document significantly different marginal labor supply responses to three reforms.
In chapter three we analyze novel survey data to document the take-up of self-protective behaviors during the early phase of the Covid-19 pandemic. We demonstrate socioeconomic gradients in the adoption of these behaviors, which are partially explained by low-income people reporting more circumstances that make engaging in these actions more difficult, such as an inability to tele-work
EXPERIMENTAL DETERMINATION OF LYOPHILIZATION HEAT TRANSFER COEFFICIENT AND VARIANCE-BASED SENSITIVITY ANALYSIS OF PRIMARY DRYING LYOPHILIZATION MODELING
Get PDFLyophilization or freeze drying is an important process in pharmaceutical industry that can enable the storage of drug product for longer durations at common storage conditions (typically 2-8° C) while preserving the potency of the active pharmaceutical ingredients. The primary drying stage of lyophilization involves the sublimation of ice formed during the freezing stage of lyophilization driven by a vapor pressure difference between the surface of the frozen product and the condenser. Because primary drying is the most energy and time-consuming step of lyophilization, optimizing the stage for faster sublimation rate and shorter drying time using primary drying model is crucial to saving costs in production. The primary drying model used connects inputs including chamber pressure and shelf temperature with outputs such as product temperature to allow for optimization of laboratory and production scale optimization.
The first part of this study uses gravimetric method to measure heat transfer coefficient of select locations within lyophilizer to analyze differences between different vial locations. The result of the study is compared to TDLAS batch records to illustrate the advantages and the disadvantages of the two methods. In the second part of the study, a variance-based global sensitivity method is used to quantify the uncertainty of the inputs and how they affect the uncertainties of drying time and product temperature. The most influential inputs and their contribution to output variance are identified for each of drying time and product temperature. Three different drug products are analyzed with global sensitivity analysis and their results compared to show the applications of sensitivity analysis. When the output is cycle time, shelf temperature has the most influence on PRODUCT 3 and PRODUCT 2 cycles, while heat transfer coefficient is the dominating influencer for the PRODUCT 1 cycle. When the output is cycle time, chamber pressure is most influential for the PRODUCT 1 cycle, shelf temperature has the largest impact on the PRODUCT 2 cycle. The PRODUCT 3 cycle is significantly influenced by both temperature and pressure. Sensitivity analysis serves as an important tool when creating lyophilization design spaces to account for uncertainties within and between different variables
CES HIPPIES DONT ON PARLE TANT : CULTURAL PASSEURS AND DISCOURSES ON AMERICAN COUNTERCULTURE IN FRANCE (1965-1975)
Get PDFThis dissertation investigates the intricacies of cultural passage as brokered by mediators, referred to as passeurs, between the United States and France during the transformative period from 1965 to 1975. Its central object is that of the intercultural translation of countercultural discourse: how do passeurs navigate multifaceted obstacles, ranging from physical and linguistic to moral and political, to relay aspects of the American counterculture to a French public? Through analyses of writings by journalists and sociologists such as Michel Lancelot, Alain Dister, and Edgar Morin, alongside influential countercultural magazines like Actuel and Rock & Folk, the study delves into the means by which 1960s-era counterculture as embodied by the hippie movement was disseminated in France. It explores the meticulous construction of an ethos of sincerity and authenticity by passeurs whose sympathetic relationship to youth facilitated the transmission in and through print of countercultural ideas. Furthermore, the research sheds light on the construction of a distinctly French version of counterculture, notably within the pages of the magazine Actuel. Not only did Actuel work to transmit American ideas and models; it also served as a crossroads, enabling French readers to build communities and identities emancipated from the parent culture’s restrictions. The example of the French production of the hit stage musical Hair exposes the challenges posed by commercial recuperation that ultimately weakened the countercultural ethos, as evidenced by the demise of Actuel itself. Core to the study's concerns is the concept of "soft activism," which in contrast to the hard activism that French youth forged in 1968 favored a nuanced and individualized approach to the dissemination of counterculture. In its focus on the legibility of the American hippie movement for a metropolitan French public, the dissertation contributes to a deeper understanding of the transnational dynamics of counterculture and of the key intermediary role of the passeur as cultural trader
DEVELOPMENT OF DIGITAL MOLECULAR DIAGNOSTIC ASSAYS FOR MULTIPLEXED NUCLEIC ACID DETECTION AT SINGLE-MOLECULE RESOLUTION
Get PDFNucleic acids are the predominant target material in molecular diagnostics, serving as essential biomarkers for genetic diseases, cancers, and pathogen identification. Existing nucleic acid detection methods include nucleic acid amplification tests (NAAT), such as polymerase chain reaction (PCR) and isothermal amplification, and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-based approaches. While each method has its distinct advantages and disadvantages, a common limitation they share is the restricted capacity for multiplexing. Despite numerous strategies to enhance the multiplexing capability of current NAAT methods, they often suffer from non-specific exponential amplification and amplification bias, which significantly impact the sensitive detection and accurate quantification of multiple targets. Furthermore, current CRISPR-based genotyping methods require two separate assays with extensive screening of CRISPR guide RNA (crRNA) to precisely determine the mutation status of a specific gene of interest.
Digital technology has enhanced the diagnostic capabilities of NAAT as a novel method that distributes each target molecule into microreactors and produces binary signals for absolute quantification of target nucleic acids. Leveraging its single-molecule detection capability, digital technology allows simultaneous detection and quantification of multiple nucleic acid targets with existing multiplexing strategies. Despite significant improvements, existing multiplexed digital assays are often too labor-intensive, rely exclusively on instruments available in limited laboratories, have complicated assay design criteria, or still face the risk of non-specific exponential amplification. There remains a need for simple, reliable, and easily accessible multiplexed nucleic acid detection assays for broad applications.
This thesis is devoted to the development of multiplexed molecular diagnostic assays that address the previously mentioned limitations of existing nucleic acid detection methods on multiplexing. We start by outlining various molecular diagnostic methods for nucleic acid detection and discussing their limitations on multiplexing (Chapter 1). Then, we develop a new multiplexing strategy of PCR-based assay that utilizes universal primers and probes with limited fluorescence colors and simple design criteria, termed “Fluorescence-coding PCR” (Chapter 2). Next, we further employ digital technology into the fluorescence-coding PCR for simultaneous detection of multiple nucleic acid targets via single-molecule detection technique (Chapter 3). We also utilize digital technology into the CRISPR-based nucleic acid detection method to expand the potential of CRISPR-based assay on nucleic acid biosensing (Chapter 4), and further develop digitized kinetic analysis method to overcome the ‘one-crRNA-one-target’ limitation and improve the multiplexing capability of CRISPR-based genotyping (Chapter 5)
ANTIMICROBIAL STRATEGIES FOR TREATMENT OF BACTERIAL AND VIRAL INFECTION
No full textAntimicrobial resistance is an unavoidable threat to global public health. One strategy to address this concern is through the identification and validation of uncharted antimicrobial targets. Broadly speaking, bacterial central metabolism is an underexplored target space. 1-Deoxy-D-xylulose 5-phosphate synthase (DXPS) is an emerging and novel antimicrobial target in bacterial central metabolism. DXPS converts its canonical substrates, pyruvate and D-glyceraldehyde 3-phosphate (D-GAP), to DXP. Research on the unique mechanism of DXPS and its function in bacterial central metabolism have greatly contributed to the development of inhibitors and strategies to target this bacterial enzyme. The work in this thesis, in part, focuses on the development of probes, inhibitors, and prodrugs towards the study of DXPS as a novel antimicrobial target.
Chapter 2 discusses challenges and successes towards generating chemical probes as tools to support the study of DXPS. We designed an activity-based probe inspired by the structure of well-known inhibitors of DXPS, alkyl acetylphosphonates (alkylAPs), and which represents the first activity-based probe for DXPS. Potent inhibition of DXPS is achieved with bisubstrate analog alkylAPs, triazole acetylphosphonates (TrAPs). Chapter 3 includes a targeted structure-activity relationship study of TrAP compounds. This study produced a TrAP compound that is the most potent AP-based DXPS inhibitor to date. Bisubstrate analog inhibitors are potent in vitro, but lack antimicrobial activity. Chapter 4 explores a prodrug strategy that masks TrAP carboxylate towards improving their antimicrobial efficacy.
The second part of this thesis focuses on a strategy for the treatment of HIV infection. Antiretroviral therapy has drastically improved treatment outcomes for HIV-positive patients. While effective, these treatments include lifelong daily oral combination therapy, which can lead to pill fatigue in patients. Long-acting (LA) formulations reduce the frequency of antiretroviral dosing, lessening pill burden in HIV-positive patients. However, hydrophilic nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs), a cornerstone of antiretroviral therapy, are not amenable to nanoformulation approaches used to generate long-acting regimens. The final Chapter of this thesis, Chapter 5, explores a reversible masking strategy for NRTIs to aid in their incorporation into LA formulations of antiretroviral drugs
EXPLORING HIV RISK PERCEPTIONS AND PRE-EXPOSURE PROPHYLAXIS AWARENESS AND PREFERENCES AMONG BLACK CISGENDER WOMEN IN BALTIMORE, MARYLAND
Get PDFBackground: Black cisgender women in Baltimore continue to be disproportionately affected by HIV. Though HIV preexposure prophylaxis (PrEP) is effective in reducing HIV transmission through sexual contact, Black cisgender women are underrepresented among PrEP users. There is a need to explore factors affecting PrEP interest among Black women.
Methods: This qualitative study utilized 26 semi-structured interviews with emerging (aged 18 to 29) and older (aged 30 to 44) adult Black cisgender women in Baltimore, Maryland between October 2021 and April 2023. Black women were eligible for this study if they were PrEP-naïve but eligible based on a self-reported HIV status of negative and reported HIV risk behaviors. Six member-checking interviews were completed. HIV risks and vulnerabilities were assessed using a combination of an interpretive phenomenological approach and case study analysis. PrEP barriers and facilitators were assessed using aspects of a grounded theory approach. PrEP preferences were assessed using an inductive approach, which began with a priori codes from a conceptual framework and the literature.
Results: Many Black women did not see themselves at risk for HIV either because of individual behavior or relationship factors. Women who considered themselves at high risk reported having condomless sex or multiple sexual partnerships, as well as engaging in sex work, injection drug use, or group sex. While Black women tried to protect themselves by using condoms and getting tested for HIV, sociostructural factors such as unequal relationship power and poverty limited their ability to protect themselves from HIV. While emerging adult and older adult Black women thought PrEP had HIV prevention benefits, they expressed many barriers to PrEP interest, including barriers at the individual- (e.g., perceived PrEP candidacy), relationship- (e.g., monogamy and trust), community- (e.g., HIV stigma), and structural-level (e.g., medical mistrust). While EA Black women preferred oral PrEP, OA Black women preferred injectable PrEP. Black women wanted to expand PrEP marketing and communication strategies.
Conclusion: This dissertation describes how sociostructural factors outside of Black women’s control, such as poverty, can influence HIV risk. Our findings highlight how systems differentially impact Black women’s uptake of PrEP
Labor, Gender, and Violence at the Missions of Seventeenth-Century Florida
Get PDFThis dissertation explores the roles of missionary violence and Indigenous resistance in the evangelization of Florida (c. 1587-1704) in order to understand the complex relations between Catholic missionaries and Guale, Timucua, and Apalachee societies in Florida. Emphasizing the importance of pre-existing Indigenous and Spanish political and religious traditions, it focuses on conflicts around gendered labor as a flashpoint to analyze the clashes and controversies that shaped Spanish colonization in Florida.
This dissertation draws on manuscript and printed sources in seven different languages (European and Indigenous), across multiple colonial and religious research institutions. It uses seventeenth-century Franciscan teaching libraries to comprehend the Franciscan missionary theology they brought to Florida, and counterbalances European sources with archaeological data. It argues that conflicts over gendered labor shaped missionary violence and Indigenous resistance. Missionaries justified their labor demands—and their use of corporal punishment to coerce it—with specific theological texts and imperatives. Spanish colonial rule in this far-flung colony drew on and extended ongoing processes in Spain. I further argue that that the concept of “commensurability” helps to explain colonization in Florida: Spanish colonial authors frequently expressed a sense of recognition or commensurability between their own and Indigenous Floridian social systems and practices. Moments when Indigenous Catholics pushed back against colonial labor demands, however, reveal the limits of this alleged commensurability. Methodological interventions in this dissertation trace ways that colonialism affected gender roles and sexuality in Indigenous Floridian societies, contributing to Indigenous feminist and public health dialogues about the colonization (and decolonization) of gender ideologies. Finally, I connect the legacy of colonial-era Florida to long national and transatlantic currents of history and social change
NANOMEDICINE BASED APPROACHES FOR TREATING MUCOSAL CONDITIONS
No full textLocal drug delivery is often preferred over systemic delivery due to a decrease in off-target effects and increase in tissue targeting. Vaginal drug delivery systems, in particular, are often preferred for treating a variety of diseases and conditions of the female reproductive tract (FRT). However, there are many anatomical and biological barriers to effective treatment via the vaginal route. Further, biocompatibility with the local tissue and microbial microenvironment is desired. Here, we investigate the use of biocompatible drug delivery vehicles for improving vaginal and mucosal drug delivery.
Current vaginal products have drawbacks, including spontaneous ejection of drug-eluting rings and unpleasant discharge from vaginal creams. Here, we describe the development and characterization of a hypotonic, gel-forming, Pluronic-based delivery system for vaginal drug administration. The hypotonic, gel-forming formulation was found to form a thin, uniform gel layer along the vaginal epithelium in mice, in contrast to the rapidly forming conventional gelling formulation containing polymer above the CGC. When this vehicle was formulated in combination with a progesterone nanosuspension (ProGel), equivalent efficacy was observed in the prevention of chemically induced preterm birth (PTB) compared to commercial Crinone® vaginal cream. Further, ProGel showed marked benefits in reducing unpleasant discharge, reducing product-related toxicity, and improving compatibility with vaginal bacteria in vitro.
Estradiol hormone replacement therapy may be prescribed to alleviate symptoms of post-menopausal vaginal atrophy. We describe the development and characterization of a mucoinert estradiol nanosuspension (NS) formulation for improved vaginal estradiol delivery. We compare the pharmacokinetics to the clinical comparator vaginal cream (Estrace) and demonstrate increased delivery of estradiol to the vaginal tissue. We utilized ovariectomized (OVX) mice as a murine model of post-menopausal vaginal atrophy and demonstrated increased delivery of estradiol to vaginal tissue and equivalent efficacy in vaginal re-epithelialization when dosed with either the estradiol NS or Estrace cream. Further, we demonstrate compatibility of the estradiol NS with vaginal bacteria in vitro. Additionally, we formulated and utilized a sulconazole nanosuspension in a patient-like swine model of bowel strictures to prevent further fibrosis. Nanosuspensions pose a viable option for biocompatible drug delivery to and through mucosal tissues