Medical Biochemistry Commons^™

Phytochemical And In-Vitro Cytotoxic Analyses Of Flavonoid Species Isolated From Chromolaena Leivensis, Luke A. Bryant

Electronic Theses and Dissertations

As a leading cause of death worldwide, cancer and its treatments remain a primary source of interest among researchers. Modern studies are looking into bioselective cytotoxicity to create new chemotherapies that do not have the same harsh side effects as those we use today. Natural product research has a promising future for the development of such treatments. Specifically, polar flavonoids may be the key to a bioselective treatment. Such flavonoid species are native to plants, often within flower petals or within the body. A natural antioxidant, they are designed not to harm healthy cells. This study focuses on the plant …

Kras-Independent Factors Drive Pi3k Signaling And Circumvent The Necessity Of Kras-Driven Pi3k Activation In Pdac, Lucas Christopher Bialousow

MUSC Theses and Dissertations

Pancreatic ductal adenocarcinoma (PDAC) has one of the lowest five-year survival rates among cancers and is characterized by near-ubiquitous occurrence of oncogenic KRAS mutations. Oncogenic KRAS activates several downstream pathways, including ERK 1/2 MAPK and PI3K, which are critical for PDAC. However, accumulating evidence suggests that PI3K activity can be maintained independent of oncogenic KRAS. The high prevalence of KRAS^G12R in PDAC challenges the prevailing model of KRAS-driven PI3K activation, as this mutant is defective in direct engagement with PI3Kα. These observations raise important questions regarding how PI3K signaling is sustained in PDAC. Here, we investigated KRAS-independent mechanisms that …

Differential Roles Of Moesin And Vasp In Β-Catenin-Associated Networks During Zebrafish Heart Regeneration, Allen Rutman

Undergraduate Theses, Capstones, and Recitals

With cardiovascular disease remaining as the leading cause of mortality worldwide, it is largely due to the limited regenerative capacity of the human heart. However, zebrafish (Danio rerio) can fully regenerate cardiac tissue following injury, providing a valuable model for studying the mechanisms of heart repair. To investigate these mechanisms, we used proteomics methods in the past. Proximity labeling is a technique that identifies proteins based on their physical proximity to a protein of interest. It can be applied in organisms and in living cells (Roux et al., 2012; Cho et al., 2020). We used proximity labeling to characterize protein …

Exploration Of A Relationship Between The Activities Of Trail And 4’-Trifluoromethoxychalcone., Abigail C. Ernst

Undergraduate Theses

Cancer is the overgrowth of dysregulated or mutated cells that affects 1 in 3 Americans. Chalcones are natural products with many possible derivatives, such as 4’-trifluromethoxychalcone (4TF), developed in Dr. Krzysiak’s lab, which exhibit anticancer activity against cancer cell lines. Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) is a tumor surveillance cytokine that acts on two receptor types: death receptors and decoy receptors. One way cancer cells can become resistant to TRAIL is by upregulating decoy receptors and/or downregulating death receptors. In this study, MTS assays evaluated the potential relationship between TRAIL and 4TF that sensitizes A549 cells to TRAIL. The …

Engineering Enac Constructs To Examine Pip2 And Ubiquitin Competition On Enac Regulation And Stability, Lacie Johnson

Chemistry & Biochemistry Undergraduate Honors Theses

The epithelial sodium channel (ENaC) plays a critical role in sodium homeostasis, fluid balance, and blood pressure regulation. ENaC activity is tightly controlled by post-translational mechanisms, including ubiquitination-mediated degradation and phosphatidylinositol 4,5-bisphosphate (PIP2) dependent channel activation. PIP2 is a phospholipid necessary to facilitate the maximal channel opening. Previous studies suggest that intracellular PIP2 binding sites are located in proximity to ubiquitination sites on ENaC subunits, raising the possibility of PIP2 binding to influence channel stability and function. This thesis aimed to engineer and validate molecular tools capable of examining the interplay between PIP2 binding and ubiquitination in ENaC regulation. A …

Hepatocyte Peroxisome Biogenesis And Phytol-Induced Metabolic Stress In Liver Disease, William Galloway

Theses, Dissertations and Capstones

Hepatocyte peroxisomes are required for metabolism of phytol-derived branched-chain fatty acids through the ACOX2-SCPx beta-oxidation pathway. This study tests whether hepatocyte-specific deletion of PEX16 (Pex16^Alb-Cre), which eliminates peroxisome biogenesis, sensitizes the liver to phytol-induced injury. The Pex16^Alb-Cre mice and their normal control Pex16^fl/fl mice were fed the Lieber-DeCarli liquid with or without 0.1 percent phytol for eight weeks. Serum alanine aminotransferase (ALT) and liver index were measured. Liver sections were stained with hematoxylin and eosin and Masson’s trichrome. Immunoblot analysis of peroxisomal enzyme expression was also performed. Phytol had no effect in Pex16^fl/fl mice as …

Evaluating The Efficacy And Safety Of Inactivated Dengue Vaccines In Vulnerable Populations, Alaa Daghash

Honors Undergraduate Theses

Dengue virus is a mosquito-borne flavivirus responsible for over 390 million annual cases worldwide. While there are live-attenuated vaccines available to prevent dengue, none are currently approved for use in the United States, and existing platforms pose significant risks of viral reactivation and antibody-dependent enhancement in vulnerable populations, such as pregnant women, children under the age of nine, and the immunocompromised. This widespread exclusion of vulnerable populations exposes a significant vaccine equity gap in dengue prevention, as the populations most at risk for severe dengue are the same ones who are currently excluded from vaccination. In this study, I conducted …

Green Synthesis Of And Antimicrobial Susceptibility Testing Of (2z)-2-[(4-Fluorophenyl)Methylidene]-1-Benzofuran-3-One, Rod Albert C. Olofernes

Honors Theses

Antimicrobial resistance is a global health challenge, rendering once-effective antibiotics less potent or entirely ineffective. In response, there is increasing interest in developing antimicrobial agents through environmentally sustainable methods. In this study, a fluorinated aurone derivative, (2Z)-2-[(4-fluorophenyl)methylidene]-1-benzofuran-3-one, was synthesized using a green Knoevenagel condensation approach. Eco-friendly catalysts were employed to minimize environmental impact and avoid hazardous byproducts. Product formation was confirmed to avoid wasting resources. The compound was evaluated for antimicrobial properties using a Kirby-Bauer plate, but did not demonstrate consistent or significant antimicrobial activity, therefore lacking promise as a standalone antibiotic.

Microneedle-Based Lc-Ms/Ms Profiling Of Dermal Interstitial Fluid Reveals Early Lipid Dysregulation Contributing To Painful Neuropathy In Prediabetic And Type 2 Diabetic Rats, Srinivasa Rao Gadam

Biomedical Sciences ETDs

Painful diabetic neuropathy (PDN), a complication of type 1 and type 2 diabetes, also occurs in obesity and prediabetes, with dyslipidemia as a modifiable risk factor. The distal-to-proximal neuropathy pattern and length-dependent intraepidermal nerve fiber loss suggest peripheral contributions. We hypothesized that elevated neurotoxic lipid intermediates—diacylglycerols (DAG), free fatty acids (FFA), and acylcarnitines (CARs)—in the dermal interstitial fluid (ISF) drive metabolism-associated hyperalgesia in prediabetic and diabetic rats. Using a microneedle array (MIA) with LC-MS/MS, we profiled ISF and serum lipids from high-fat diet (HFD) and HFD + streptozotocin (STZ) rat models alongside Hargreaves testing. ISF lipid changes appeared earlier (weeks …

Novel Piperidone And Bispidine Derivatives: A New Approach In Cancer Therapy, Lereen Khaled Youssry

Theses and Dissertations

Cancer remains the second leading cause of death worldwide. As a result, scientists have been trying to find novel therapeutic approaches that target specific metabolic pathways selective to tumor cells. In this study, two novel piperidone and bispidine derivatives, organic molecules that target polyamine metabolism, were synthesized, and their potential cytotoxic, antioxidant and anti-inflammatory effects were investigated. Polyamines are naturally occurring metabolites that were reported to be in excess at cancer cells and were accounted for tumor proliferation, invasion and metastasis. Accordingly, the novel piperidone and bispidine derivatives were expected to disrupt tumor growth and progression via up-regulation of key …

Carbon Monoxide Releasing Polymeric Micelles, Riya Joshi

Electronic Theses and Dissertations

Carbon monoxide (CO), traditionally known as a toxic gas, has emerged as a potential therapeutic agent due to its cytoprotective, anti-inflammatory, and vasodilatory properties. This study explores the development of CO-releasing polymeric micelles as a controlled delivery system for biomedical applications. Using ring-opening metathesis polymerization (ROMP), we synthesized diblock copolymers incorporating CO-releasing moiety diphenylcyclopropenone (DPCP) with hydrophilic polyethylene glycol (PEG) to enhance solubility and stability of the overall CO releasing system. Dynamic light scattering (DLS) and electron microscopy (EM) confirmed the formation of well-defined micelles, while fluorescence assays demonstrated efficient CO release with the use of Iridium photocatalyst under 470 …

The Impact Of An Iron-Rich Diet On Fatigue In Menstruating Women With Non-Anemic Iron Deficiency, Meagan Seraydar, Lauren Latimer, Sam Miragliatto

Department of Nutrition Student Projects

Fatigue without diagnosed anemia is prevalent in menstruating women, with iron deficiency being a potential contributor. While iron supplementation is a standard intervention, dietary sources of iron may offer a sustainable alternative. This study aims to assess the impact of an iron-rich diet on fatigue levels in menstruating women. A 12-week randomized controlled trial (RCT) will be conducted, assigning participants to either an iron-rich diet group or a control group following their usual diet without specific iron recommendations. Fatigue will be measured using the Fatigue Severity Scale (FSS) at baseline, six weeks, and twelve weeks, alongside iron status biomarkers, including …

Synthetic Protein Mimetic Based Therapies For Neurodegeneration, Nicholas H. Stillman

Electronic Theses and Dissertations

Protein-protein interactions (PPIs) are crucial for the regulation of a majority of, if not every fundamental cellular process. Despite their role in regular biological processes, dysregulated and/or aberrant protein-protein interactions (aPPIs) are often related to the onset of disease including cancer, viral infection, and amyloid diseases. aPPIs have historically been deemed ‘undruggable’ due to their large surface area and lack of a binding cavity; however, today, more than 40 disease-related aPPIs have been targeted with small molecules and several of those have reached clinical trials.

A class of synthetic protein mimetics called oligopyridylamides (OPs) has been shown to inhibit disease-related …

Alpha-Synuclein Interaction With Gedunin, Tony Matundura Nyabayo

Graduate Theses/Dissertations

Parkinson’s disease (PD) and other Proteinopathies develop when α-synuclein misfolds and aggregates into toxic amyloids. While existing treatments for PD are primarily focused on managing its symptoms, a viable solution for slowing down the progress of Parkinson’s disease involves targeting the toxic α-synuclein amyloids. Gedunin, a natural inhibitor of heat shock protein 90, has been extensively used to treat malaria. Also, recent research investigations have shed light on its potential beyond malaria therapy, indicating that Gedunin may offer a possible solution for treating a variety of neurodegenerative diseases. Using plate-based assays, we examined how Gedunin influences α-synuclein fibrillation and its …

Targeting The Cholesterol Storage Enzyme Acat1/Soat1 In Brain Cells And Mouse Model: A Novel Approach To Address Aging And Apoe4-Related Neuroinflammation, Thao Nguyen Phuong Huynh Krumeich

Dartmouth College Ph.D Dissertations

Alzheimer’s Disease (AD) is a progressive neurodegenerative disease that significantly impacts nearly 7 million people in the United States. AD is characterized by the deposition of amyloid beta (Ab) plaque, tau neurofibrillary tangles (NFTs), lipids granules, and neuroinflammation. Age and apolipoprotein E4 (APOE4) are the two biggest risk factors for AD. Recent AD therapeutic development has mostly benefited the patient population with milder symptoms while causing serious side effects in APOE4 carriers, leaving the most impacted patients’ group - aged APOE4 carriers with no treatment option. With the increasing aging population, there is an urgent need for a …

Combination Therapy Of Ido1 Inhibition And Anti-Pd1 Mediates Anti-Tumor Immunity By Promoting Memory Immunity Development And Cytotoxicity Of Γδ T And Nk Cells Via Il-2 Signaling And By Overcoming Pro-Tumor Effects Of Tgf-Β Signaling, Hyuk Jee

Dartmouth College Master’s Theses

Cutaneous melanoma is the most aggressive form of skin cancer even though it takes only about 1% of all skin cancers. Even among all cutaneous melanomas, NRAS-mutant melanoma is more aggressive than any other, and about 10-25% of all cutaneous melanoma cases have mutations in NRAS. NRAS is a member of the RAS family of proto-oncogenic GTPase proteins, and it plays a key role in signal transduction pathways responsible for cellular survival, proliferation, and metabolism. Immunotherapy is the first line of defense against NRAS-mutant melanoma because, despite tremendous efforts made for decades, it has not been successful to develop small …

E6 Inhibtion-Mediated Combinatorial Therapy For Hpv+ Hnscc, Sonia Whang

Loma Linda University Electronic Theses, Dissertations & Projects

High-risk human papillomaviruses (HPV) are the causative agents of virtually all cases of cervical cancer and up to 80% of head and neck squamous cell carcinoma (HNSCC). Current treatment options include chemo- and radiotherapy, though the effectiveness of these therapies is limited by the viral oncoprotein E6, which disrupts apoptotic pathways by binding to and accelerating the degradation of molecules such as p53 and caspase- 8. Our hypothesis was that inhibiting E6 and rescuing the apoptotic mediators would increase the effectiveness of apoptotic agents. The aims of this study were to first, develop an HPV+ HNSCC xenograft model to test …

Sex And Age Differences In Near-Infrared Spectroscopy Responses And The Resulting Influences On Cognition, Miranda K. Traylor

Graduate Theses and Dissertations (2019 - present)

Vascular dysfunction is the earliest known marker of neurodegeneration. However, limited research has been conducted to determine if changes in peripheral vascular function track differences in brain health. Therefore, the purpose was to determine if previously reported sex differences in near-infrared spectroscopy (NIRS) vascular occlusion test (VOT) parameters persist across the lifespan and if these differences track age- and sex-related differences in a cognitive task. Ninety-nine healthy, cognitively intact adults (50 women, 49 men) across the adult lifespan (19-81 yrs) were used for analysis. The combination of NIRS-VOT was used to quantify microvascular function. Cognition was defined as the time …

Immunotherapeutic Properties Of Virus Like Particles Displaying Allergens In A Mouse Model Of House Dust Mite Allergy, Piyachat Patniboon

Chulalongkorn University Theses and Dissertations (Chula ETD)

House dust mite (HDM) represents one of the most prominent sources of allergens. The rising prevalence of HDM-induced allergic diseases such as allergic rhinitis, allergic asthma or atopic dermatitis is a major global health challenge. Allergen immunotherapy (AIT), by frequent administrations of HDM allergen extracts, is the unique treatment capable of alleviating the Th2-biased allergic response through the induction of immune tolerance. However, AIT faces limitations in terms of duration, efficacy and safety, explaining the poor patient adherence. Clinical efficacy of HDM extract-based AIT was shown to be dependent on the selection of patients sensitized to the two major HDM …

Depletion Of Oxalate In High-Oxalate Beverages By Positively Charged Particles, Sukrita Aungsuthan

Chulalongkorn University Theses and Dissertations (Chula ETD)

Excessive dietary intake of oxalate is a key risk factor of calcium oxalate (CaOx) nephrolithiasis. Therefore, limiting daily oxalate intake is recommended to prevent CaOx stone formation. Black tea and coffee are commonly consumed beverages that are rich in oxalate, and avoidance of tea and coffee consumption is relatively hard. In this study, therefore, we aimed to develop a novel tool for depleting oxalate in black tea and coffee. Since oxalate is negatively charged, we hypothesized that positively charged particles would be an effective tool for capturing and removing oxalate. Hydroxyapatite (HA) and calcium alginate (Ca-Alg) beads were fabricated and …

Exploring The Skin Microbiome Of Alopecic Cynomolgus Macaques (Macaca Fascicularis) Based On Oxford Nanopore Technologies, Natthanit Phokkhasub

Chulalongkorn University Theses and Dissertations (Chula ETD)

Alopecia or hair loss in captive non-human primates (NHPs) such as cynomolgus macaques is a major concern of animal welfare in many primate facilities. The purpose of this study is to investigate the association between alopecic and healthy skin microbiome in cynomolgus macaques. This study included skin swab samples (head, arm, leg, ventral, and dorsal areas) collected from 33 healthy and 50 alopecic macaques housed at the NPRCT-CU. LEfSe analysis revealed the significant bacteria found in multiple areas of the alopecic group, including P. copri and L. animalis. The significant fungi found in double areas (arm-dorsal, dorsal-head, and leg-ventral) of …

Roles Of Mtor Complex 2 Signaling In The Sphingolipid Production Of Brain Cancer Cell Lines, Nuanwan Songcharoen

Chulalongkorn University Theses and Dissertations (Chula ETD)

Gliomas, which include low- and high-grade types, represent a particularly aggressive form of primary brain tumor, especially glioblastoma (GBM). Metabolic reprogramming in lipid metabolism supports cell proliferation; alterations in the sphingolipid pathway, elevated glucosylceramide (GlcCer) levels through glucosylceramide synthase (GCS), promote the production of glycosphingolipids, which serve as building blocks for cancer cells. Furthermore, mTORC2, which is a kinase protein, contributes to lipid metabolism. Thus, the study aims to investigate the roles of mTORC2 signaling in lipid metabolism through lipid accumulation, which was reduced with AZD8055 treatment as the mTORC2 inhibitor. Additionally, p-AKT (S473), which is downstream of mTORC2, was …

Ftsk Regulates The Assembly Of The Division Machinery In The Ftsz-Less Chlamydia Trachomatis, Mckenna Katherine Harpring

Theses and Dissertations (ETD)

In evolving to obligate intracellular dependence, Chlamydia trachomatis serovar L2 (Ct), has eliminated several gene products essential for cell division in most other bacteria, including FtsZ, the central coordinator of divisome assembly. In the absence of FtsZ, we show that divisome assembly in Ct is initiated by FtsK, a chromosomal translocase. Chlamydial FtsK forms discrete foci at the septum and at the base of the progenitor mother cell, and our data indicate that FtsK foci at the base of the mother cell mark the location of nascent divisome complexes that form at the site where a daughter cell will emerge …

The Role Of Uric Acid In Metabolic Abnormalities Of Obesity, Andrew P. Giromini

Graduate Theses, Dissertations, and Problem Reports (ETD)

Uric acid (UA) is the single most tightly associated metabolite for obesity and type 2 diabetes. While the field varies on whether UA is causative or correlative of the metabolic dysfunction allied to obesity, these studies use different diets and animal models to make these claims. It is the goal of this dissertation to compare different diets commonly used in this research to delve deeper into the data and determine which diets induce elevated circulating UA levels as well as which diets also induce metabolic dysfunction. Early chapters of this dissertation examine the comparison of high fructose consumption, both in …

Investigating The Role Of Maternal Adiposity On Human Breast Milk And Preterm Infant Stool Short Chain Fatty Acid And Microbiome Profiles, Kristy L. Thomas

Electronic Theses and Dissertations

Preterm birth is the number one cause of death in neonates, accounting for 35% of neonatal mortality. The preterm birth rate in the U.S. in 2021 was 10.5%, disproportionally affected by race and ethnicity. Obese women have an increased risk of preterm pregnancy, and if delivered before 37 weeks of gestation, the offspring have higher rates of complications that extend from the neonatal period into life-long metabolic and immune adverse outcomes. In the early months after delivery, preterm infants have higher rates of adverse health outcomes than term infants, including infections, extrauterine growth restrictions, respiratory, metabolic, and neurological complications, necrotizing …

Design Of An Fgf-1-Fgf-2 Heterodimer Variant With Enhanced Stability And Cell Proliferation Activity, Nicholas Alan Pohlman

Chemistry & Biochemistry Undergraduate Honors Theses

The FGF-1 subfamily, composed of FGF-1 and FGF-2, assists in broad health-related processes such as cell proliferation and angiogenesis respectively.^1,2 The subfamily shows promising signs as a therapeutic, however, the inherent thermal instability leads to a low half-life in vivo.³ To assist in improving the stability, FGF-1 and FGF-2 were connected via a 12-residue glycine linker ultimately producing a heterodimer. This heterodimer was further examined to discover its novel properties. Inspiration for this project was drawn from previous research which performed five mutations on FGF-1 ultimately improving stability in the protein complex. In addition to these five …

Molecular And Biochemical Analysis Of Cytochrome P450 2c19 And 2d6, Reema Saleous

Theses

Pharmacogenomics (PGx) is a relatively new field of study. It links genetics to pharmacology since it deals with the influence of the genetic makeup of the individual on their ability to respond to specific medications. Some of the most important genes in this field, dubbed very important pharmacogenes (VIPs), belong to the cytochrome P450 (CYP) superfamily of drug metabolizing enzymes. The two members of this family that are the main focus of this thesis are CYP2C19 and CYP2D6. They play major roles in the metabolism of numerous medications, and it is therefore imperative that variations within those genes in various …

Exogenous Exposure To Dihydroxyacetone Mimics High Fructose Induced Oxidative Stress And Mitochondrial Dysfunction, Raj Mehta

Honors Theses

Dihydroxyacetone (DHA) is a three-carbon sugar that is the active ingredient in sunless tanning products and a by-product of electronic cigarette (e-cigarette) combustion. Increased use of sunless tanning products and e-cigarettes has elevated exposures to DHA through inhalation and absorption. Studies have confirmed that DHA is rapidly absorbed into cells and can enter into metabolic pathways following phosphorylation to dihydroxyacetone phosphate (DHAP), a product of fructose metabolism. Recent reports have suggested metabolic imbalance and cellular stress results from DHA exposures. However, the impact of elevated exposure to DHA on human health is currently under-investigated. We propose that exogenous exposures to …

Photodynamic Therapy Agents: The Power Of Mjöllnir To Eradicate Cancer, Sidney M. Hopper

Honors College Theses

After its discovery back in the 1900s, photosensitizers became a critical study for potential treatments and cures for medical issues, including cancer. It was discovered that porphyrins appeared to target and accumulate in proliferating cells, and to reach the cells, a certain wavelength of light with maximum absorbance associated with the porphyrin was necessary to achieve cell death. Photodynamic therapy involves making use of porphyrins or metalloporphyrins as activators when exposed to such light. When activated, these compounds generate reactive oxygen species (ROS), such as HO- or O2-, which can react with nucleic acids found in DNA and RNA. In …

Fragment Based Drug Development Based On 6,7-Dimethoxyquinazoline As A Core Scaffold, Cody M. Orahoske

ETD Archive

The work entitled “Fragment Based Drug Design based on 6,7- Dimethoxyquinazoline core structure” presents a unique approach to drug discovery, specifically focusing on the pharmacophore 6,7-dimethoxyquinazoline. This study explores the structural diversity of 6,7-Dimethoxyquinazoline derivatives to identify other pharmacologically relevant targets, with evidence indicating that this core structure possesses intrinsic properties that make it suitable as a base structure of small molecule drugs. Furthermore, this pharmacophore has been observed in various approved therapeutics or drug candidates under investigation, highlighting its importance in drug discovery. My research showcases of 6,7-dimethoxyquinazoline core structure been derivatized to generate an anti-trypanosomiasis drug candidates and …