Biology Commons^™

Mitochondria Imaging And Targeted Cancer Treatment, Tinghan Zhao

Dissertations

Mitochondria are essential organelles as the site of respiration in eukaryotic cells and are involved in many crucial functions in cell life. Dysfunction of mitochondrial metabolism and irregular morphology have been frequently found in human cancers. The capability of imaging mitochondria as well as regulating their microenvironment is important both scientifically and clinically. Mitochondria penetrating peptides (MPPs), certain peptides that are composed of cationic and hydrophobic amino acids, are good candidates for mitochondria targeting. Herein, a novel MPP, D-argine-phenylalanine-D-argine-phenylalanine-D-argine-phenylalanine-NH₂ (rFrFrF), is conjugated with a rhodamine-based fluorescent chromophore (TAMRA). The TAMRA-rFrFrF probe exhibits advantageous properties for long-term mitochondria tracking of …

Vines In The Neotropics: Phylogenomics, Biogeography And Systematics In Passion Flowers (Passiflora Subgenus Decaloba Section Decaloba), Serena Acha

Dissertations

With 600 species, Passiflora is a large, morphologically complex and broadly distributed genus in Passifloraceae that represents a major challenge to scientists interested in understanding the evolutionary history of tropical vines. Passiflora has been divided into subgenera, super sections and sections. One of the most enigmatic and species-rich (~120 spp.) groups in Passiflora is section Decaloba, which occurs in the Neotropics and is particularly diverse in Andean montane forests. In this study, we used phylogenomic and population genomic approaches to investigate the evolutionary history, biologeography, species boundaries, and taxonomy of Passiflora section Decaloba. We sampled herbarium specimens, extracted …

The Role Of Multidrug Resistance Regulators Mara, Soxs, Rob And Rama In Regulating Virulence Traits In Salmonella Enterica, Srinivas Thota

Dissertations

Enteric pathogens sense numerous signals specific to the anatomical location in the intestine and integrate them with the complex regulatory networks to temporally and spatially regulate their virulence genes. MarA, SoxS, Rob and RamA are homologous transcription factors that belong to AraC family of proteins in Salmonella enterica that primarily were thought to be involved in rendering antibiotic resistance to bacteria by up regulating efflux pumps and down regulating outer membrane porins. The fact that these transcription factors respond to the same intestinal compounds that regulate virulence genes in Salmonella motivated us to look for other roles of these transcription …

Taxonomy, Species Limits, And Phylogenetic Relationships Of Anoura Gray 1838 (Chiroptera: Phyllostomidae), Camilo Andres Calderon Acevedo

Dissertations

This dissertation addresses several aspects of the diversity and species limits in the nectarivorous bat genus Anoura Gray 1838(Chiroptera: Glossophaginae). Based on morphometric approaches, the current taxonomic arrangement for Anoura includes 8 to 10 species; however, previous taxonomic revisions did not include all closely related species in the genus. In Chapter 1, I investigate the identity of Anoura carishina and its position in the morphospace of the large-bodied Anoura using craniodental and external variables. I analyze traits thought to be diagnostic for these species, including 1) an elliptical Fourier transformation analysis of the shape of the third upper premolar …

Peroxisomal Protein Defects Disrupt Coordinated Peroxisomal Processes And Affect Early Seedling Development Through Accumulating Toxic Catabolic Intermediates, Ying Li

Dissertations

Many peroxisomal proteins act in β-oxidation processes on a range of substrates. It is unclear how these proteins are coordinated to determine the flux of peroxisomal processes and meet the requirements for plant growth and development. Using mutant analysis and metabolic profiling, I examined proteins predicted to act in fatty acid and indole-butyric-acid (IBA) β-oxidation. ECH2 confers enoyl-CoA hydratase activity for the auxiliary β-oxidation of fatty acids with an even cis-unsaturated bond. ECH2 was suggested to function in IBA β-oxidation, as ech2 seedlings have altered IBA response. ech2 seedlings have reduced root length and cotyledon area. ech2 seedlings accumulate 3-hydroxyoctenoate …

Deciphering The Molecular Mechanism Through Which Rhus Coriaria Exerts Its Anti-Cancer Activity, Khawlah Najib Saeed Athamneh

Dissertations

Cancer remains a major health problem around the globe. Among various types of treatments, plants have been shown to have great capacity in cancer treatment, one of which is Rhus coriaria. Commonly known as sumac, Rhus coriaria is a culinary herb that is known to possess different therapeutic values including anti-oxidant and anti-microbial activities.

In this Ph.D. project, we tested the effect of Rhus coriaria extract (RCE) on the migration, invasion, and metastasis of MDA-MB-231 human breast cancer cells. We showed that non-cytotoxic concentrations of RCE inhibited migration and invasion, blocked adhesion to fibronectin, and downregulated MMP-9. Additionally, we found …

Alcohol Induced Bacterial Changes In The Setting Of Colitis, Paulius Kuprys

Dissertations

Inflammatory bowel diseases (IBD) affect a large number of individuals around the world. This group of diseases is largely composed of two types: Crohn's disease (CD) and ulcerative colitis (UC). Upon development of IBD, patients experience cyclical episodes of inflammation, known as flares. Flare induction appears to arise from multiple factors, which can also vary on a person-to-person basis. Alcohol has been shown to trigger IBD flares and onset, though the underlying mechanism has not been established.Defining factors of the IBD intestinal environment include an altered microbiome, bacterial infiltration of the intestinal epithelium, and increased leakage of proinflammatory bacterial byproducts. …

Daxx As A Restrictor Of Tumor Initiating Cell Survival In Er+ Breast Cancer And Its Therapeutic Implications, Daniel Seamus Peiffer

Dissertations

Breast cancer overall is the second most common cause of cancer related death in women, with one in eight women being diagnosed during their lifetime. Breast cancer itself is divided into subtypes based on the expression levels of the hormone receptors including the estrogen receptor (ER) and the progesterone receptor (PR), as well as expression of the growth factor receptor epidermal growth factor receptor 2 (HER2). ER+ breast cancer is the most common breast cancer diagnosis, and these tumors are defined as being initially dependent on activation of the receptor for growth. Based on this, targeted endocrine therapies (ETs) have …