Life Sciences Commons^™

Histological Characterization Of Inter Ictal Epileptiform Discharges Generating Brain Regions Using A Preclinical Model Of Focal Cortical Dysplasia, Abhay S. Deshmukh

FIU Electronic Theses and Dissertations

Current clinical practice of resective surgery in focal epilepsy involves electroencephalogram (EEG) brain source imaging to localize irritative brain areas from where Inter-ictal epileptiform discharges (IEDs) emerge, useful to localize the seizures-onset zones. Unfortunately, there are no previous systematic studies to characterize the pathophysiological mechanisms and abnormal cellular substrates in these irritative areas since histological data are available only from the final resective zones. To address this issue we applied a combination of EEG brain imaging described by Bae et al. (2015) using cutting-edge technology for high-density scalp EEG in rodents and histological analysis on a chronic rat model of …

Regional Evolutionary Distinctiveness And Endangerment As A Means Of Prioritizing Protection Of Endangered Species, Emily K. Brantner

FIU Electronic Theses and Dissertations

Conservation is costly, and choices must be made about where to best allocate limited resources. I propose a regional evolutionary diversity and endangerment (RED-E) approach to prioritization of endangered species. It builds off of the evolutionary diversity and global endangerment (EDGE) approach, but will allow conservation agencies to focus their efforts on species in specific regions. I used the RED-E approach to prioritize mammal and bird species listed under the U.S. Endangered Species Act (ESA), as well as to make a ranking of species without ESA critical habitat (CH), as a practical application. Regional conservation approaches differ significantly from global …

Robust Modeling And Predictions Of Greenhouse Gas Fluxes From Forest And Wetland Ecosystems, Khandker S. Ishtiaq

FIU Electronic Theses and Dissertations

The land-atmospheric exchanges of carbon dioxide (CO₂) and methane (CH₄) are major drivers of global warming and climatic changes. The greenhouse gas (GHG) fluxes indicate the dynamics and potential storage of carbon in terrestrial and wetland ecosystems. Appropriate modeling and prediction tools can provide a quantitative understanding and valuable insights into the ecosystem carbon dynamics, while aiding the development of engineering and management strategies to limit emissions of GHGs and enhance carbon sequestration. This dissertation focuses on the development of data-analytics tools and engineering models by employing a range of empirical and semi-mechanistic approaches to robustly …

Development Of A Maldi-Tof-Ms Method For The Analysis Of Cyanobacterial Neurotoxin Β-N-Methylamino-L-Alanine (Bmaa) In Search Of Bmaa Incorporation In Biological Samples, Laura M. Conklin

FIU Electronic Theses and Dissertations

Beta-N-methylamino-L-alanine (BMAA) is a non-protein amino acid produced by many cyanobacteria, and thought to induce neurotoxic effects through excitotoxicity, contributing to neurodegenerative diseases such as Amyotrophic Lateral Sclerosis/Parkinsonism-dementia complex (ALS-PDC) and Alzheimer’s. The ubiquitous nature of cyanobacteria, and evidence of biomagnification through our food web, creates a dire need for the development of an analytical platform that will provide accurate identification and quantification of BMAA amounts in our ecosystem and potential food supply. The present study evaluated the ability of a MALDI-ToF-MS method to detect and quantify BMAA in a variety of biological matrices. Through validation procedures, it …

The Role Of Endothelin 3 In Melanoma Progression And Metastasis, Nikeisha L. Chin

FIU Electronic Theses and Dissertations

Endothelin receptor b (Ednrb) and its ligand Endothelin 3 (Edn3) have been implicated in melanoma. Several studies have shown an upregulation of EDNRB and EDN3 at both the protein and mRNA levels, as melanoma becomes more aggressive. This study investigated the putative role played by Edn3 over-expression in melanoma progression and angiogenesis in vivo. We crossed Tg(Grm1)Epv transgenic mice that aberrantly express metabotropic glutamate receptor1 under the Dopachrome tautomerase promoter, leading to spontaneous melanocytic lesions in the ears and tails that do not metastasize, with transgenics that overexpress Edn3 under the Keratin 5 promoter ( …

The Effect Of Disturbance And Freshwater Availability On Lower Florida Keys’ Coastal Forest Dynamics, Danielle E. Ogurcak

FIU Electronic Theses and Dissertations

Coastal forest retreat in the Florida Keys during the 20^th century has been attributed to a combination of sea level rise and hurricane storm surge impacts, but the interactions between these two disturbances leading to forest decline are not well understood. The goal of my research was to assess their effects over a period spanning more than two decades, and to examine the relationships between these press and pulse disturbances and freshwater availability in pine rockland, hardwood hammock, and supratidal scrub communities. Impacts and recovery from two storm surges, Hurricanes Georges (1998) and Wilma (2005), were assessed with satellite-derived …

Regulatory Mechanisms Of Leishmania Aquaglyceroporin Aqp1, Mansi Sharma

FIU Electronic Theses and Dissertations

Pentavalent antimonials [Sb(V)] are the primary drug of choice against all forms of leishmaniasis. Emergence of antimony unresponsiveness is a major issue. There is a dire need of understanding antimony resistance mechanisms in Leishmania. One important mechanism is the down regulation of the trivalent antimony [Sb(III)] (the active form of Sb(V)) uptake system. To date, Leishmania aquaglyceroporin AQP1 is the only reported facilitator of Sb(III). Leishmania do not have promoters. They primarily regulate their genes at post-transcriptional and/or post-translational levels. We reported that mitogen activated protein kinase 2 (MPK2) positively regulated AQP1 stability through the phosphorylation of the threonine …

The Effect Of Vitamin D Supplementation On Cardiovascular Risk Factors Among Minorities With Type 2 Diabetes, Joel Exebio

FIU Electronic Theses and Dissertations

The aim of the present study was to determine the effect of vitamin D supplementation (4000 IU or 6000 IU of cholecalciferol daily for 6 months) on fasting plasma glucose, fasting insulin, glycated hemoglobin, and lipid profile in a sample of African-Americans and Hispanics with T2D and vitamin D insufficiency. Seventy five participants were recruited by community outreach. Plasma glucose concentration was measured by hexokinase enzymatic method. Glycated hemoglobin was measured by the DCA2000+ system. Insulin in fasting blood was determined by radioimmunoassay. Plasma total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein cholesterol were assayed by enzymatic methods. Serum vitamin …

In Search Of Safety, Negotiating Everyday Forms Of Risk: Sex Work, Criminalization, And Hiv/Aids In The Slums Of Kampala, Serena Cruz

FIU Electronic Theses and Dissertations

This dissertation offers an in-depth descriptive account of how women manage daily risks associated with sex work, criminalization, and HIV/AIDS. Primary data collection took place within two slums in Kampala, Uganda over the course of fourteen months. The emphasis was on ethnographic methodologies involving participant observation and informal and unstructured interviewing. Insights then informed document analysis of international and national policies concerning HIV prevention and treatment strategies in the context of Uganda. The dissertation finds social networks and social capital provide the basis for community formation in the sex trade. It holds that these interpersonal processes are necessary components for …

Caffeine Intake And Its Association With Disease Progression, Sleep Quality And Anxiety Symptoms And Nutritional Alterations In People Living With Hiv In The Miami Adult Studies On Hiv Cohort, Venkataraghavan Ramamoorthy

FIU Electronic Theses and Dissertations

Miami-Dade County has approximately 27,000 people living with HIV (PLWH), and the highest HIV incidence in the nation. PLWH have reported several types of sleep disturbances. Caffeine is an anorexic and lipolytic stimulant that may adversely affect sleep patterns, dietary intakes and body composition. High caffeine consumption (>250 mg. per day or the equivalent of >4 cups of brewed coffee) may also affect general functionality, adherence to antiretroviral treatment (ART) and HIV care. This study assess the relationship of high caffeine intake with markers of disease progression, sleep quality, insomnia, anxiety, nutritional intakes and body composition.

A convenience sample …

Sex-Positive Curricula: An Investigation Of The Relationship Between Physical Fitness, Self-Concept And Sexual Functioning, Lia Jiannine

FIU Electronic Theses and Dissertations

Despite the well-recognized benefits of exercise, Americans are gaining weight in astounding proportions and levels of physical activity are on the decline. The purpose of this study was to investigate a relationship between physical fitness, self-concept and sexual health. There is a dearth of knowledge on this relationship specifically in the context of sex-negative curricula, which is the dominate discourse in the United States.

One hundred and thirty-three participants between the ages of 18 - 50 volunteered for fitness testing and data collection. Physical fitness was assessed through body fat, resting metabolic rate, cardiovascular endurance, muscular strength, muscular endurance and …

Label-Free Surface-Enhanced Raman Spectroscopy-Linked Immunosensor Assay (Slisa) For Environmental Surveillance, Vinay Bhardwaj

FIU Electronic Theses and Dissertations

The contamination of the environment, accidental or intentional, in particular with chemical toxins such as industrial chemicals and chemical warfare agents has increased public fear. There is a critical requirement for the continuous detection of toxins present at very low levels in the environment. Indeed, some ultra-sensitive analytical techniques already exist, for example chromatography and mass spectroscopy, which are approved by the US Environmental Protection Agency for the detection of toxins. However, these techniques are limited to the detection of known toxins. Cellular expression of genomic and proteomic biomarkers in response to toxins allows monitoring of known as well as …

Determination Of Extracellular Molecules Produced By Vibrio Harveyi Using Ms/Ms, Jose G. Roble

FIU Electronic Theses and Dissertations

Quorum sensing (QS) is a process that allows bacteria to sense the population density of cells around them by communicating with each other via autoinducer molecules. This cross-communication is crucial in the regulation of bacterial processes such as bioluminescence, virulence, and biofilm formation. Previous research by Milburn and Makemson on Vibrio harveyi suggested that in addition of the known biosynthesis of three well-characterized autoinducers, dozens of unknown molecules are also produced and released to the environment by V. harveyi. This study was performed using electrospray tandem mass spectrometry with the purpose of detection and characterization of the extracellular molecules …

Mangiferin As A Biomarker For Mango Anthracnose Resistance, Herma Pierre

FIU Electronic Theses and Dissertations

Mangos (Mangifera indica L.) are tropical/subtropical fruits belonging to the plant family Anacardiaceae. Anthracnose is the most deleterious disease of mango both in the field and during postharvest handling. It is most commonly caused by the Colletotrichum gloeosporioides complex. Mangiferin, a xanthanoid compound found in at least twelve plant families worldwide (Luo et al., 2012), is present in large amounts of the leaves and edible mangos. Even though this compound plays a pivotal role in the plant’s defense against biotic and abiotic stressors, no correlations been made between the compound and mango anthracnose resistance.

Mangos were collected, grouped …

Investigating Trophic Interactions Of Deep-Sea Animals (Sharks, Teleosts, And Mobile Scavengers) In The Gulf Of Mexico Using Stable Isotope Analysis, Diana A. Churchill

FIU Electronic Theses and Dissertations

The deep-sea is the largest habitat on earth, containing over 90 percent of the world’s oceans and home to over 20,000 species. Deep-sea ecosystems are increasingly impacted by human activities including fishing and oil extraction. To understand potential impacts on deep-sea food webs, it is crucial to gather baseline data in these systems. I quantified the trophic interactions of three groups of deep-water animals across a range of trophic levels living in the northern and eastern Gulf of Mexico using stable isotope analysis. First, I propose methods for correcting δ¹⁵N values for the presence of nitrogenous metabolic waste …

The Effects Of Fire On Spore Viability Of Lygodium Microphyllum (Old World Climbing Fern), Nicole Sebesta

FIU Electronic Theses and Dissertations

Lygodium microphyllum, native to the Old World tropics, has invaded central and southern Florida, destroying native habitats, reducing biodiversity and altering fire regimes. Prescribed fire, one of several methods used to manage L. microphyllum infestations, reduces fern biomass over large areas, but its effects on spore viability are unknown. To provide tools to evaluate whether fire-dispersed spores are viable, this research determined how heat affects spore viability. Spores were exposed to temperatures of 50°C to 300°C for durations of 5 seconds to 1 hour, then allowed to germinate on agar in petri plates. Percent germination was assayed after two …

Employing Limited Next Generation Sequence Data For The Development Of Genetic Loci Of Phylogenetic And Population Genetic Utility, Lauren Evenstone

FIU Electronic Theses and Dissertations

Massively parallel high throughput sequencers are transforming the scientific research by reducing the cost and time necessary to sequence entire genomes. The goal of this project is to produce preliminary genome assemblies of calliphorid flies using Life Technologies’ Ion Torrent sequencing and Illumina’s MiSeq sequencing. I located, assembled, and annotated a novel mitochondrial genome for one such fly, the little studied Chrysomya pacifica that is central to one hypothesis about blow fly evolution. With sequencing data from Chrysomya megacephala, its forensically relevant sister species, much insight can be gained by alignments, sequence and protein analysis, and many more tools …

Characterization Of An Epoxide Hydrolase From The Florida Red Tide Dinoflagellate, Karenia Brevis, Pengfei Sun

FIU Electronic Theses and Dissertations

Polyether compounds are a subgroup of natural products with regular occurrence of multiple C-O-C motifs. The biosynthetic origin of polycylic polethers has been studied and the majority of them are derived from polyketide or terpene pathways. Normally, the polycyclic polyethers can be divided into two groups based on their structural features: the first group features multiple rings that are interconnected by carbon-carbon single bond, which are produced by a biosynthetic cascade of exo epoxide-opening reactions; the other group has multiple fused cyclic ethers and are formed by an cascade of endo epoxide-opening reactions.

Karenia brevis (K. brevis) is …

Investigating The Driving Mechanisms Behind Differences In Bleaching And Disease Susceptibility Between Two Scleractinian Corals, Pseudodiploria Strigosa And Diploria Labyrinthiformis, Zoe A. Pratte

FIU Electronic Theses and Dissertations

Disease and bleaching are two conditions which commonly lead to coral death. Among coral species, susceptibility to disease and bleaching is variable, and Pseudodiploria strigosa tends to be diseased more than Diploria labyrinthiformis, while D. labyrinthiformis bleaches more readily. The focus of this dissertation was to investigate and compare multiple components of these two coral species, and identify how they may relate to disease and bleaching resistance. Compenetnts examined included the surface mucopolysacharide layer (SML) thickness, gene expression, microbial associates, and a white plague aquarium study. The SML thickness decresased with increasing temperature regardless of coral species, indicating that SML …

An Integrated Neuroimaging Approach For The Prediction And Analysis Of Alzheimer’S Disease And Its Prodromal Stages, Qi Zhou

FIU Electronic Theses and Dissertations

This dissertation proposes to combine magnetic resonance imaging (MRI), positron emission tomography (PET) and a neuropsychological test, Mini-Mental State Examination (MMSE), as input to a multidimensional space for the classification of Alzheimer’s disease (AD) and it’s prodromal stages including amnestic MCI (aMCI) and non-amnestic MCI (naMCI). An assessment is provided on the effect of different MRI normalization techniques on the prediction of AD. Statistically significant variables selected for each combination model were used to construct the classification space using support vector machines. To combine MRI and PET, orthogonal partial least squares to latent structures is used as a multivariate analysis …

The Effects Of Climate Warming On Plant-Herbivore Interactions, Nathan Lemoine

FIU Electronic Theses and Dissertations

Rising temperatures associated with climate change will alter the fundamental physiological processes of most ectothermic species. Drastic changes in catabolic and anabolic reaction rates exert strong effects on growth, reproduction, and consumption rates that cascade up through all levels of the biological hierarchy. This dissertation determined how climate warming might alter the important relationship between plants and insect herbivores, as mediated through changes in herbivore physiology. Consumption and fitness increased with temperature for almost all consumers. However, all consumers also exhibited a critical temperature, beyond which consumption declined rapidly through metabolism continued to increase. This mismatch in metabolic demands and …

Changing Bacterial Growth Efficiencies Across A Natural Nutrient Gradient In An Oligotrophic Estuary, Amber A. Kiger

FIU Electronic Theses and Dissertations

Recent studies have characterized coastal estuarine systems as important components of the global carbon cycle. This study investigated carbon cycling through the microbial loop of Florida Bay by use of bacterial growth efficiency calculations. Bacterial production, bacterial respiration, and other environmental parameters were measured at three sites located along a historic phosphorus-limitation gradient in Florida Bay and compared to a relatively nutrient enriched site in Biscayne Bay. A new method for measuring bacterial respiration in oligotrophic waters involving tracing respiration of ¹³C-glucose was developed. The results of the study indicate that ¹³C tracer assays may provide a better …

Pollination, Herbivory, And Habitat Fragmentation: Their Effects On The Reproductive Fitness Of Angadenia Berteroi, A Native Perennial Plant Of The South Florida Pine Rocklands, Beyte Barrios Roque

FIU Electronic Theses and Dissertations

Angadenia berteroi is a tropical perennial subshrub of the pine rocklands with large yellow flowers that set very few fruits. My dissertation seeks to elucidate the factors that affect the reproductive fitness of Angadenia berteroi a native species of the south Florida pine rocklands. I provide novel information on the pollination biology of this native species. I also assess the effects of herbivory on growth and the reproductive success of A. berteroi. Finally, I elucidate how habitat fragmentation and quality are correlated with reproductive fitness of this native perennial plant.

Using a novel experimental approach, I determined the most effective …

Intracranial Volume Estimation And Graph Theoretical Analysis Of Brain Functional Connectivity Networks, Saman Sargolzaei

FIU Electronic Theses and Dissertations

Understanding pathways of neurological disorders requires extensive research on both functional and structural characteristics of the brain. This dissertation introduced two interrelated research endeavors, describing (1) a novel integrated approach for constructing functional connectivity networks (FCNs) of brain using non-invasive scalp EEG recordings; and (2) a decision aid for estimating intracranial volume (ICV). The approach in (1) was developed to study the alterations of networks in patients with pediatric epilepsy. Results demonstrated the existence of statistically significant (p

Evaluation Of Some Statistical Methods For The Identification Of Differentially Expressed Genes, Andrew L. Haddon

FIU Electronic Theses and Dissertations

Microarray platforms have been around for many years and while there is a rise of new technologies in laboratories, microarrays are still prevalent. When it comes to the analysis of microarray data to identify differentially expressed (DE) genes, many methods have been proposed and modified for improvement. However, the most popular methods such as Significance Analysis of Microarrays (SAM), samroc, fold change, and rank product are far from perfect. When it comes down to choosing which method is most powerful, it comes down to the characteristics of the sample and distribution of the gene expressions. The most practiced method is …

The Effect Of Sample And Sample Matrix On Dna Processing: Mechanisms For The Detection And Management Of Inhibition In Forensic Samples, Lilliana I. Moreno

FIU Electronic Theses and Dissertations

The presence of inhibitory substances in biological forensic samples has, and continues to affect the quality of the data generated following DNA typing processes. Although the chemistries used during the procedures have been enhanced to mitigate the effects of these deleterious compounds, some challenges remain. Inhibitors can be components of the samples, the substrate where samples were deposited or chemical(s) associated to the DNA purification step. Therefore, a thorough understanding of the extraction processes and their ability to handle the various types of inhibitory substances can help define the best analytical processing for any given sample. A series of experiments …

A Comparative Study Of Concurrent Acoustic And Diver Survey Data, And Fish Community Descriptions Of A High Latitude Coral Reef, Florida, Usa, Adam M. Zenone

FIU Electronic Theses and Dissertations

Fisheries independent data on relatively unstudied nekton communities were used to explore the efficacy of new tools to be applied in the investigation of shallow coastal coral reef habitats. These data obtained through concurrent diver visual and acoustic surveys provided descriptions of spatial community distribution patterns across seasonal temporal scales in a previously undocumented region. Fish density estimates by both diver and acoustic methodologies showed a general agreement in ability to detect distributional patterns across reef tracts, though magnitude of density estimates were different. Fish communities in southeastern Florida showed significant trends in spatial distribution and seasonal abundance, with higher …

Intracellular Signaling And Trafficking In Cancer: Role Of Rab5-Gtpase In Migration And Invasion Of Breast Cells, Nicole Porther

FIU Electronic Theses and Dissertations

Metastasis is characterized pathologically by uncontrolled cell invasion, proliferation, migration and angiogenesis. Steroid hormones, such as estrogen, and growth factors, which include insulin growth factor I/II (IGF-1/IGF-2) therapy has been associated with most if not all of the features of metastasis. It has been determined that IGF-1 increases cell survival of cancer cells and potentiate the effect of E2 and other ligand growth factors on breast cancer cells. However not much information is available that comprehensively expounds on the roles of insulin growth factor receptor (IGFR) and Rab GTPases may play in breast cancer. The latter, Rab GTPases, are small …

Characterization Of The Poxab Operon Encoding A Class D Carbapenemase In Pseudomonas Aeruginosa,, Diansy Zincke

FIU Electronic Theses and Dissertations

Pseudomonas aeruginosa is a dreaded opportunistic pathogen that causes severe and often intractable infections in immunocompromised and critically ill patients. This bacterium is also the primary cause of fatal lung infections in patients with cystic fibrosis and a leading nosocomial pathogen responsible for nearly 10% of all hospital-acquired infections. P. aeruginosa is intrinsically recalcitrant to most classes of antibiotics and has the ability to acquire additional resistance during treatment. In particular, resistance to the widely used β-lactam antibiotics is frequently mediated by the expression of AmpC, a chromosomally encoded β-lactamase that is ubiquitously found in P. aeruginosa strains. This dissertation …

Overweight/Obesity And Hiv Disease Progression In Hiv+ Adults In Botswana, Sabrina Sales Martinez

FIU Electronic Theses and Dissertations

Studies indicate that overweight and obesity protect against HIV-disease progression in antiretroviral therapy (ART)-naïve patients. We examined retrospectively the relationship of overweight/obesity with HIV-disease progression in ART-naïve HIV+ adults in Botswana in a case-control study with 18-month follow-up, which included 217 participants, 139 with BMI 18.0-24.9 kg/m² and 78 with BMI ≥25 kg/m². Archived plasma samples were used to determine inflammatory markers: leptin and bacterial endotoxin lipopolysaccharide (LPS), and genotype single nucleotide polymorphisms (SNPs) of the Fat Mass and Obesity Associated Gene (FTO).

At baseline, BMI was inversely associated with risk for AIDS-defining conditions (HR=0.218; 95%CI=0.068, 0.701, …