Biochemistry, Biophysics, and Structural Biology Commons^™

Electrohydrodynamic Simulations Of Capsule Deformation Using A Dual Time-Stepping Lattice Boltzmann Scheme, Charles Leland Armstrong

Mathematics & Statistics Theses & Dissertations

Capsules are fluid-filled, elastic membranes that serve as a useful model for synthetic and biological membranes. One prominent application of capsules is their use in modeling the response of red blood cells to external forces. These models can be used to study the cell’s material properties and can also assist in the development of diagnostic equipment. In this work we develop a three dimensional model for numerical simulations of red blood cells under the combined influence of hydrodynamic and electrical forces. The red blood cell is modeled as a biconcave-shaped capsule suspended in an ambient fluid domain. Cell deformation occurs …

The Effects Of Sugar Osmolytes On Reverse Micelle Systems, Jenna Deckard, Bridget Gourley Phd

Annual Student Research Poster Session

Reverse Micelles (RM) are nanoscopic pools of water encapsulated by an amphipathic surfactant molecule that allows the water pool to be suspended in a nonpolar solvent. We use RM systems because they allow for the study of water and dissolved osmolyte interactions in confinement. Gaining an understanding of how sugars interact with water in confinement has significant implications for biological systems. This project seeks to understand the effects of galactose as an osmolyte on the interactions, loading limits, and size of RMs when compared to RMs containing only water and RMs containing glucose. Galactose and glucose have slight structural differences, …

Awegnn: Auto-Parametrized Weighted Element-Specific Graph Neural Networks For Molecules., Timothy Szocinski, Duc Duy Nguyen, Guo-Wei Wei

Mathematics Faculty Publications

While automated feature extraction has had tremendous success in many deep learning algorithms for image analysis and natural language processing, it does not work well for data involving complex internal structures, such as molecules. Data representations via advanced mathematics, including algebraic topology, differential geometry, and graph theory, have demonstrated superiority in a variety of biomolecular applications, however, their performance is often dependent on manual parametrization. This work introduces the auto-parametrized weighted element-specific graph neural network, dubbed AweGNN, to overcome the obstacle of this tedious parametrization process while also being a suitable technique for automated feature extraction on these internally complex …

Host-Parasite Interactions Within Food Webs, Adam Zvanut Hasik

Graduate Theses and Dissertations

Parasitism is one of the most common life history strategies employed in nature, yet the effects of parasites are often thought to be minimal, and the vast majority of studies fail to consider parasites and their effects on host organisms. This is likely a problem, as the magnitude of parasite-mediated effects on their hosts can be quite large. Additionally, the effects of parasites are known to extend beyond the host to affect other species interactions. I used a series of approaches to gain a more integral understanding of host-parasite interactions by studying (1) the effects of parasites on biotic interactions …

Divergent Regulatory Roles Of Nurd Chromatin Remodeling Complex Subunits Gatad2 And Chd4 In Caenorhabditis Elegans, Nicole Lynn Golden

Theses and Dissertations

During stress, a protective cellular network known as the heat shock response (HSR) is induced to maintain protein-folding homeostasis, or proteostasis. While the HSR is essential for stress resistance, its misregulation is associated with neurodegenerative disease and cancer. Using the nematode model organism Caenorhabditis elegans, we have identified the chromatin remodeling complex NuRD (nucleosome remodeling and deacetylase) as a novel regulator of the HSR. Here, we begin with a brief introduction of the HSR and chromatin remodeling complexes in C. elegans, prior to presenting our findings in a series of two chapters. In chapter one, we outline a set of …

Genetically Encoded Multivalent Liquid Glycan Array Displayed On M13 Bacteriophage, Amira Khalil, Mirat Sojitra, Jasmine Maghera, Emily Rodrigues, Eric J. Carpenter, Shaurya Seth, Daniel Ferrer Vinals, Todd L. Lowary

Pharmacy

The central dogma of biology does not allow for the study of glycans using DNA sequencing. We report a liquid glycan array (LiGA) platform comprising a library of DNA ‘barcoded’ M13 virions that display 30–1,500 copies of glycans per phage. A LiGA is synthesized by acylation of the phage pVIII protein with a dibenzocyclooctyne, followed by ligation of azido-modified glycans. Pulldown of the LiGA with lectins followed by deep sequencing of the barcodes in the bound phage decodes the optimal structure and density of the recognized glycans. The LiGA is target agnostic and can measure the glycan-binding profile of lectins, …

Distinct Spatiotemporal Regulation Of The Cytoprotective Heat Shock Response In Caenorhabditis Elegans, Rosemary Nadine Plagens

Theses and Dissertations

Every organism studied to-date utilizes the heat shock response (HSR) to maintain protein-folding homeostasis (proteostasis) during temperature or other protein-folding stress. The HSR has been well characterized using acute heat stress (HS) in single-celled models, but less is known about how distinct cell types and tissues respond to HS. Furthermore, how metazoans respond to prolonged HS at the molecular level remains relatively unexplored. The model organism C. elegans, with its genetic tractability and distinct tissues and behaviors, has been used extensively in the field to characterize the acute HSR, but with considerable variability across labs regarding HS temperature and duration. …

Survival Kinetics And Antimicrobial Interventions To Mitigate Foodborne Pathogen Contamination Of Low-Moisture Foods, Rajat Sharma

Theses and Dissertations

Contamination of low-moisture foods (LMFs) with foodborne pathogens such as Salmonella and Shiga-toxin producing Escherichia coli (STEC) has been rising over the last couple of years. Commodity groups such as peanuts, tree nuts, and their products are frequently recalled when associated with illness outbreaks resulting from these pathogens. In this project, two major challenges related to understanding the survival kinetics of pathogens and the efficacy of novel antimicrobial treatments in mitigating their risk in LMFs were systematically investigated. Studies were conducted for determining the survival kinetics of three Salmonella spp. strains in three different tree nut flours (i.e., almond, chestnut, …

Toward Sustainable Production Of Value-Added Bioenergy And Industrial Oils In Oilseed And Biomass Feedstocks, Kiyoul Park, Sanju A. Sanjaya, Truyen Quach, Edgar B. Cahoon

Department of Biochemistry: Faculty Publications

Plant fatty acids are used for food, feed, fuel, and industrial materials. Structurally and chemically diverse fatty acids, referred to as unusual or specialized fatty acids, are found in the seed oils of diverse plant species. Many unusual fatty acids have potential use as alternative and renewable sources of biofuels and bio-based industrial feedstocks due to their variant structures' physical or functional properties. Oils enriched in these fatty acids can increase the value of oilseed crops and provide co-products that can be readily extracted from lignocellulosic materials in biomass crops. Here, we describe recent progress on strategies for enhancement of …

Administrative Coding In Electronic Health Care Record-Based Research Of Nafld: An Expert Panel Consensus Statement, Hannes Hagström, Leon A Adams, Alina M Allen, Christopher D Byrne, Yoosoo Chang, Henning Grønbaek, Mona Ismail, Peter Jepsen, Fasiha Kanwal, Jennifer Kramer, Jeffrey V Lazarus, Michelle T Long, Rohit Loomba, Philip N Newsome, Ian A Rowe, Seungho Ryu, Jörn M Schattenberg, Marina Serper, Nick Sheron, Tracey G Simon, Elliot B Tapper, Sarah Wild, Vincent Wai-Sun Wong, Yusuf Yilmaz, Shira Zelber-Sagi, Fredrik Åberg

Faculty, Staff and Students Publications

BACKGROUND AND AIMS: Electronic health record (EHR)-based research allows the capture of large amounts of data, which is necessary in NAFLD, where the risk of clinical liver outcomes is generally low. The lack of consensus on which International Classification of Diseases (ICD) codes should be used as exposures and outcomes limits comparability and generalizability of results across studies. We aimed to establish consensus among a panel of experts on ICD codes that could become the reference standard and provide guidance around common methodological issues.

APPROACH AND RESULTS: Researchers with an interest in EHR-based NAFLD research were invited to collectively define …

Factors Associated With Access To And Receipt Of Liver Transplantation In Veterans With End-Stage Liver Disease, Fasiha Kanwal, Ruben Hernaez, Yan Liu, Thomas J Taylor, Abbas Rana, Jennifer R Kramer, Aanand D Naik, Donna Smith, Tamar Taddei, Steven M Asch

Faculty, Staff and Students Publications

IMPORTANCE: Organ scarcity means few patients with advanced liver disease undergo a transplant, making equitable distribution all the more crucial. Disparities may arise at any stage in the complex process leading up to this curative therapy.

OBJECTIVE: To examine the rate of and factors associated with referral, wait-listing, and receipt of liver allografts.

DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used linked data from comprehensive electronic medical records and the United Network of Organ Sharing. Adult patients with cirrhosis and a Model for End-Stage Liver Disease with addition of sodium score of at least 15 points between October 1, …

Central And Peripheral Arterial Diseases In Chronic Kidney Disease: Conclusions From A Kidney Disease: Improving Global Outcomes (Kdigo) Controversies Conference, Kirsten L Johansen, Pranav S Garimella, Caitlin W Hicks, Philip A Kalra, Dearbhla M Kelly, Sven Martens, Kunihiro Matsushita, Pantelis Sarafidis, Manish M Sood, Charles A Herzog, Michael Cheung, Michel Jadoul, Wolfgang C Winkelmayer, Holger Reinecke, Conference Participants

Faculty, Staff and Students Publications

Chronic kidney disease (CKD) affects about 10% of all populations worldwide, with about 2 million people requiring dialysis. Although patients with CKD are at high risk of cardiovascular disease and events, they are often underrepresented or excluded in clinical trials, leading to important knowledge gaps about how to treat these patients. KDIGO (Kidney Disease: Improving Global Outcomes) convened the fourth clinical Controversies Conference on the heart, kidney and vasculature in Dublin, Ireland, in February 2020, entitled Central and Peripheral Arterial Diseases in Chronic Kidney Disease. A global panel of multidisciplinary experts from the fields of nephrology, cardiology, neurology, surgery, radiology, …

Sex-Related Disparities In Cardiovascular Health Care Among Patients With Premature Atherosclerotic Cardiovascular Disease, Michelle T Lee, Dhruv Mahtta, David J Ramsey, Jing Liu, Arunima Misra, Khurram Nasir, Zainab Samad, Dipti Itchhaporia, Safi U Khan, Richard S Schofield, Christie M Ballantyne, Laura A Petersen, Salim S Virani

Faculty, Staff and Students Publications

IMPORTANCE: There is a paucity of data regarding secondary prevention care disparities in women with premature and extremely premature atherosclerotic cardiovascular disease (ASCVD), defined as an ASCVD event at 55 years or younger and 40 years or younger, respectively.

OBJECTIVE: To evaluate sex-based differences in antiplatelet agents, any statin, high-intensity statin (HIS) therapy, and statin adherence in patients with premature and extremely premature ASCVD.

DESIGN, SETTING, AND PARTICIPANTS: This was a cross-sectional, multicenter, nationwide VA health care system-based study with patients enrolled in the Veterans With Premature Atherosclerosis (VITAL) registry. The study assessed patients who had at least 1 primary …

Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams

Senior Theses

Colitis is an inflammatory bowel disorder (IBD) whose etiology is attributed to modification in the luminal microbiota and dysregulation in the immune response. Indole is a signaling molecule which is naturally produced by gut luminal microbiota. Indole-3- carbinol (I3C) is a compound commonly found in vegetables and a ligand for the aryl hydrocarbon receptor (AhR). Previous studies have detected decreased expression and activation on the AhR receptor in colitis patients, thought to possibly alter gut microbiota metabolism, subsequently promoting colitis. 1 AhR, expressed in a variety of immune and epithelial cells, contributes to gut homeostasis by affecting vital mediators such …

Characterization Of Iron-Sulfur Cluster Biogenesis In Methanogenic Archaea, Thomas Modlin Deere

Graduate Theses and Dissertations

Iron-sulfur (Fe-S) clusters are among the oldest cofactors on the planet, used by proteins in almost all forms of life on Earth to carry out processes ranging from energy transfer to DNA replication. Among the organisms believed to use these Fe-S proteins more extensively than almost any others are the methanogens, an ancient lineage of archaeal microbes that produce methane as a required product of their metabolism. Methane, the primary component of commercial natural gas, is both a potent greenhouse gas and an important fossil fuel. It can also be renewably produced as a biofuel. Biogenic methane is almost entirely …

The Characterization Of Angiopoietin-Like Protein 4 Overexpression In Triple Negative Breast Cancer, Jodi Simeon

Graduate Theses and Dissertations

Triple Negative Breast Cancer (TNBC) is highly invasive and metastatic with approximately 15% of patients developing liver metastases. The primary treatment of metastatic TNBC is chemotherapy, however, there is an increased chance of resistance to this therapeutic technique. If Breast Cancer Liver Metastasis (BCLM) is left untreated most patients survive only 4 to 8 months with a very rare 5-year survival. Therefore, it is imperative to analyze markers and molecular pathways that TNBC cells use to progress, invade, and metastasize to the liver. The aim of this study was to examine the overexpression of angiopoietin-like 4 (ANGPTL4) in TNBC cells …

Evaluating Bioenergetics And Mitochondrial Dynamics In Patient Fibroblasts With Pathogenic Mitochondrial Dna Mutations Causing Leigh Syndrome, Ajibola Bakare

Graduate Theses and Dissertations

Leigh syndrome (LS) is a rare fatal mitochondrial disorder of infants caused by pathogenic mutations in the nuclear (nDNA) or mitochondrial DNA (mtDNA) leading to mitochondrial dysfunction. The extent to which pathogenic mtDNA variants regulate disease severity in LS is not well understood. The heterogeneous nature of this disorder, based in part by complex mitochondrial genetics, and the nuclear and mitochondrial cross-talk has made it particularly challenging to investigate and develop therapies for treating LS . While the prognosis is poor, several studies are underway to understand the pathophysiology of LS. This dissertation provides a comprehensive structural and functional analysis …

A Time-Course Characterization Of Muscle Function And Mitochondrial Markers During Colorectal Cancer-Induced Cachexia In Tumor-Bearing Male Mice, Ana Cabrera Ayuso

Graduate Theses and Dissertations

Cachexia is a multisystemic and multifactorial syndrome prevalent in cancer patients. It is clinically defined by involuntary loss of >5% weight in a six-month window, despite nutritional interventions. A negative energy balance characterizes cancer cachexia (CC), it is associated with weakness and fatigue in skeletal muscle. Impaired muscle function is associated with lower quality of life in cancer patients. Defects in mitochondrial function are strongly associated with muscle wasting. This study explored muscular contractile function and mitochondrial quality control (MQC) markers in soleus, gastrocnemius, and tibialis anterior (TA) muscles of C26-induced male tumor-bearing mice during a 25-day time course. It …

Characterization Of Ph – Responsive Nanocage Based On The Ferritin Iron Storage Protein, Satyam Singh

Theses and Dissertations

The iron-storage protein ferritin (Ftn) assembles into a protein cage structure with 24 subunits and octahedral (4-fold, 3-fold, 2-fold) symmetry. Each monomeric subunit contains a robust four-helix bundle fold. The fully assembled Ftn structure has a high degree of thermal stability (up to 100°C), a mono dispersed size (12 nm in diameter), and a large central cavity (7-8 nm in diameter). The central cavity stores ferric iron in phylogenetically diverse group of organisms, including humans. The central cavity has been used for encapsulation of cargoes such as other metals, contrast agents for imaging, small molecule drugs for therapy, …

High Burden Of Subclinical And Cardiovascular Disease Risk In Adults With Metabolically Healthy Obesity: The Atherosclerosis Risk In Communities (Aric) Study, Yvonne Commodore-Mensah, Mariana Lazo, Olive Tang, Justin B Echouffo-Tcheugui, Chiadi E Ndumele, Vijay Nambi, Dan Wang, Christie Ballantyne, Elizabeth Selvin

Faculty, Staff and Students Publications

OBJECTIVE: It is controversial whether adults who are obese but "metabolically healthy" have cardiovascular disease (CVD) risk comparable with that of normal-weight adults. High-sensitivity cardiac troponin T (hs-cTnT), a biomarker of myocardial damage, is useful in characterizing subclinical CVD. We categorized obesity phenotypes and studied their associations with subclinical and clinical CVD and CVD subtypes, including heart failure (HF).

RESEARCH DESIGN AND METHODS: We conducted cross-sectional and prospective analyses of 9,477 adults in the Atherosclerosis Risk in Communities (ARIC) study. We used the Adult Treatment Panel III criteria and BMI to define obesity phenotypes as follows: metabolically healthy normal weight, …

Computational Analysis Of Type 3 Iodothyronine Deiodinase: Potential Inhibitors, Substrate Binding, And Dimer Structure, Eric Scott Marsan

Chemistry & Biochemistry Theses & Dissertations

Thyroid hormones (THs) in mammalian tissues are crucial for development and maintaining metabolic homeostasis. Iodothyronine deiodinases (Dios) remove iodines from THs by a selenocysteine (Sec) residue, which either activates or inactivates them. Halogen bonding (XB) has been proposed to describe the interaction between the Se and I atoms of the T4-Dio complex. Disruption of TH homeostasis by xenobiotics, such as polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) can cause deleterious effects on the endocrine system. Experimental studies have indicated that PBDEs and PCBs could disrupt TH homeostasis by inhibiting Dio through XB formation. However, no current quantitative study exists …

Hierarchical Harmonization Of Atom-Resolved Metabolic Reactions Across Metabolic Databases, Huan Jin, Hunter N. B. Moseley

Molecular and Cellular Biochemistry Faculty Publications

Metabolic models have been proven to be useful tools in system biology and have been successfully applied to various research fields in a wide range of organisms. A relatively complete metabolic network is a prerequisite for deriving reliable metabolic models. The first step in constructing metabolic network is to harmonize compounds and reactions across different metabolic databases. However, effectively integrating data from various sources still remains a big challenge. Incomplete and inconsistent atomistic details in compound representations across databases is a very important limiting factor. Here, we optimized a subgraph isomorphism detection algorithm to validate generic compound pairs. Moreover, we …

Free Three-Dimensional Carborane Carbanions, H.D.A. Zzzchathumal Jayaweera, Md. Mamdudur Rahman, Perry J. Pellechia, Mark D. Smith, Dmitry V. Peryshkov

Faculty Publications

Carbon atom functionalization via generation of carbanions is the cornerstone of carborane chemistry. In this work, we report the synthesis and structural characterization of free ortho-carboranyl [C₂B₁₀H₁₁]⁻, a three-dimensional inorganic analog of the elusive phenyl anion that features a “naked” carbanion center. The first example of a stable, discrete C(H)-deprotonated carborane anion was isolated as a completely separated ion pair with a crown ether-encapsulated potassium cation. An analogous approach led to the isolation and structural characterization of a doubly deprotonated 1,1′-bis(o-carborane) anion [C₂B₁₀H₁₀] …

Isolation And Characterization Of Ethyl Acetate Fraction From Abroma Augusta L As An Anti-Inflammatory Agent, Madyawati Latief, Indra Lasmana Tarigan, Muhaimin Muhaimin, Hilda Amanda, Nike Desvi Yulianti

Makara Journal of Science

Abroma augusta is a bush plant that lives on the edge of the river. This plant is commonly used as an anti-inflammatory drug for joints and broken bones. It contains several secondary metabolites, such as alkaloids, triterpenoids, steroids, and flavonoids, which exhibit anti-inflammatory activity. UV-visible (UV-Vis) spectrophotometry of isolate 1.3 indicated absorption at a maximum wavelength of 282 nm. The wavelength suggested that the electron transition π–π* is the absorption of UV spectra typical for triterpenoid compounds that have chromophores in the form of non-conjugated double bonds. FT-IR spectrophotometer characterization data from isolate 1.3 revealed the presence of triterpenoid compounds …

Gene Therapy Knockdown Of Hippo Signaling Induces Cardiomyocyte Renewal In Pigs After Myocardial Infarction, Shijie Liu, Ke Li, Leonardo Wagner Florencio, Li Tang, Todd R Heallen, John P Leach, Yidan Wang, Francisco Grisanti, James T Willerson, Emerson C Perin, Sui Zhang, James F Martin

Faculty, Staff and Students Publications

Human heart failure, a leading cause of death worldwide, is a prominent example of a chronic disease that may result from poor cell renewal. The Hippo signaling pathway is an inhibitory kinase cascade that represses adult heart muscle cell (cardiomyocyte) proliferation and renewal after myocardial infarction in genetically modified mice. Here, we investigated an adeno-associated virus 9 (AAV9)–based gene therapy to locally knock down the Hippo pathway gene Salvador (Sav) in border zone cardiomyocytes in a pig model of ischemia/reperfusion-induced myocardial infarction. Two weeks after myocardial infarction, when pigs had left ventricular systolic dysfunction, we administered AAV9-Sav …

Evolution Of Targeted Therapy Resistance In Eml4-Alk Positive Non-Small Cell Lung Cancer, Robert Vander Velde

USF Tampa Graduate Theses and Dissertations

Targeted therapies have emerged as potent treatments that lead to the remission of many tumors. However, they rarely cure cancers in advanced, metastatic settings. This is due to the evolution of resistance, which in turn can be ascribed to the survival of small subpopulations of tolerant and/or resistant cells. Here we investigated the evolution of resistance to EML4-ALK inhibitors in non-small cell lung cancer (NSCLC) and demonstrated that resistance evolves gradually, from unique pre-treatment sub-populations, as multiple resistance mechanisms accumulate in a Darwinian fashion. Despite accumulating multiple changes, cells evolved, in parallel, toward similar inhibitor specific phenotypes. Evolving cells have …

Transcriptomic And Functional Investigation Of Bacterial Biofilm Formation, Brooke R. Nemec

USF Tampa Graduate Theses and Dissertations

Staphylococcus aureus and Acinetobacter baumannii are two highly successful human pathogens, which have adopted very different, but effective survival strategies. The success of S. aureus is attributed to the tight regulation of an arsenal of virulence factors. Conversely, A. baumannii lacks what would be considered traditional virulence factors and, instead, has developed a high tolerance for environmental stress, which allows it to persist in unforgiving environments, including nosocomial settings and the human body. One common characteristic of these two organisms is their proclivity for biofilm formation. Herein, we discuss the diverse mechanisms governing biofilm formation for A. baumannii and S. …

Somatic Inhibition By Microscopic Magnetic Stimulation, Hui Ye

Biology: Faculty Publications and Other Works

Electric currents can produce quick, reversible control of neural activity. Externally applied electric currents have been used in inhibiting certain ganglion cells in clinical practices. Via electromagnetic induction, a miniature-sized magnetic coil could provide focal stimulation to the ganglion neurons. Here we report that high-frequency stimulation with the miniature coil could reversibly block ganglion cell activity in marine mollusk Aplysia californica, regardless the firing frequency of the neurons, or concentration of potassium ions around the ganglion neurons. Presence of the ganglion sheath has minimal impact on the inhibitory effects of the coil. The inhibitory effect was local to the …

Flow Visualization And Aerosol Characterization Of Respiratory Jets Exhaled From A Mannequin Simulator, Sindhu Reddy Mutra

USF Tampa Graduate Theses and Dissertations

It is important to understand the airborne transmission of infectious diseases due to the COVID-19 pandemic. Physical experiments were conducted to understand the dispersion of aerosols emitted from a mannequin simulator replicating human tidal breathing through the nose and mouth with and without a protective face mask in an enclosed space. Flow patterns are observed via high-speed visualization, and the concentration and size distribution of the particles is measured as a function of distance from the mannequin using an optical particle sizer. Masks were shown to effectively reduce the horizontal dispersion of aerosol for both mouth and nose breathing. Further, …

Cytoplasmic Polyadenylation Element Binding Protein 2 Alternative Splicing Regulates Hif1Α During Chronic Hypoxia, Emily M. Mayo

USF Tampa Graduate Theses and Dissertations

Chronic pulmonary hypoxia commonly results in the sustained expression of HIF1 (hypoxia inducible factor 1), a heterodimeric transcription factor, that, if unrestrained, can result in dramatic vasculature remodeling, pulmonary arterial hypertension, and right-sided heart failure. Together, these pulmonary disorders cost approximately $100 billion annually to treat due to the limited therapeutic targets designed to inhibit HIF1 expression. In this study, we introduce a translational regulator of HIF1 expression, known as Cytosolic polyadenylation element binding proteins 2 (CPEB2). Our lab has previously demonstrated in cancer cells that alternatively spliced isoforms of CPEB2 regulate the translation of the HIF1 oxygen-dependent subunit, HIF1α, …