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- Title
- Thermodynamics-structure correlations of interactions between metalloproteinases and tissue inhibitors of metalloproteinase variants.
- Creator
- Wu, Ying., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The 23 matrix metalloproteinases (MMPs) in humans catalyze the turnover of all protein components of the extracellular matrix (ECM) and have important roles in tissue remodeling, wound healing, embryo implantation, cell migration and shedding of cell surface proteins. Excess MMP activities are associated with many diseases including arthritis, heart disease and cancer. The activities of MMPs are regulated by a family of four protein inhibitors, the tissue inhibitors of metalloproteinases ...
Show moreThe 23 matrix metalloproteinases (MMPs) in humans catalyze the turnover of all protein components of the extracellular matrix (ECM) and have important roles in tissue remodeling, wound healing, embryo implantation, cell migration and shedding of cell surface proteins. Excess MMP activities are associated with many diseases including arthritis, heart disease and cancer. The activities of MMPs are regulated by a family of four protein inhibitors, the tissue inhibitors of metalloproteinases (TIMPs), that are endogenous inhibitors of matrix metalloproteinases (MMPs), ADAMs (A Disintegrin And Metalloproteinase) and ADAMTS (disintegrin-metalloproteinase with thrombospmdin motifs) .... The balance between TIMPs and active metzinicins is very important and imbalances are linked to human diseases such as arthritis, cancer, and atherosclerosis. The engineering of TIMPs to produce specific inhibitors of individual MPs could provide new therapeutic principles for disease treatment, but this requires a detailed understanding of the biophysical and structural basis of the interactions of TIMPs and MMPs and ADAMs.
Show less - Date Issued
- 2012
- PURL
- http://purl.flvc.org/FAU/3356904
- Subject Headings
- Proteolytic enzymes, Metalloproteinase, Inhibitors, Apoptosis, Extracellular matrix proteins
- Format
- Document (PDF)
- Title
- Thermodynamic profiles of the interactions of suramin, chondroitin sulfate, and pentosan polysulfate with the inhibitory domain of tissue inhibitor of metalloproteinases 3.
- Creator
- Logue, Timothy, Brew, Keith, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Tissue inhibitor of metalloproteinase-3 (TIMP-3) is a protein with multiple functions that include regulating the turnover of the extracellular matrix (ECM) by inhibiting members of the metzincin family. Extracellular levels of soluble TIMP-3 are low, reflecting its binding to components of the ECM including sulfated glycosaminoglycans (SGAGs) and its endocytosis by low density lipoprotein receptor-related protein 1. Because TIMP-3 inhibits ECM-degrading enzymes, the ability of SGAG mimetics...
Show moreTissue inhibitor of metalloproteinase-3 (TIMP-3) is a protein with multiple functions that include regulating the turnover of the extracellular matrix (ECM) by inhibiting members of the metzincin family. Extracellular levels of soluble TIMP-3 are low, reflecting its binding to components of the ECM including sulfated glycosaminoglycans (SGAGs) and its endocytosis by low density lipoprotein receptor-related protein 1. Because TIMP-3 inhibits ECM-degrading enzymes, the ability of SGAG mimetics to elevate extracellular concentrations of TIMP3 is of interest for osteoarthritis treatment. However, previous studies of such interactions have utilized immobilized forms of the protein or ligands. Here we have quantified the thermodynamics of the interactions of the inhibitory domain of TIMP-3 with chondroitin sulfate (CS), pentosan polysulfate (PPS) and suramin in solution using isothermal titration calorimetry. All three interactions are driven by a (favorable) negative enthalpy ychange combined with an unfavorable decrease in entropy. The heat capacity change (ΔCp) for the interaction of N-TIMP-3 with CS, PPS, or suramin is essentially zero, indicating an insignificant contribution from the hydrophobic effect. Based on the effects of ionic strength on the interaction of N-TIMP-3 with suramin, their interaction appears to be driven by electrostatic interactions. Modeling supports the view that the negatively charged sulfates of CS, PPS, and suramin interact with a cationic region on N-TIMP-3 that includes Lys -26, -27, -30, and -possibly 76 on the opposite face of TIMP-3 from its reactive site for metalloproteases.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013328
- Subject Headings
- Tissue Inhibitor of Metalloproteinases, Osteoarthritis--Treatment, Suramin, Chondroitin Sulfates, Pentosans
- Format
- Document (PDF)
- Title
- THERMALLY INDUCED VARIATIONS IN VERTEBRAL NUMBER IN LUCANIA PARVA BAIRD (ANTHERINIFORMES: CYPRINODONTIDAE) REARED IN THE LABORATORY.
- Creator
- MCCARTHY, LINDA J., Florida Atlantic University, Courtenay, Walter R. Jr., Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Embryos of Lucania parva Baird from two sites in the Florida Keys were raised in four temperature regimes, 18°, 22°, 26°, and 30°C to determine the response of vertebral numbers to different incubation temperatures. The result was in inverse linear relationship, with vertebral numbers increasing with decreasing temperature. Temperature modified the developmental rates, causing the embryos in the warm temperatures to hatch earlier than those in the cold temperatures.
- Date Issued
- 1978
- PURL
- http://purl.flvc.org/fcla/dt/13951
- Subject Headings
- Biology, Zoology
- Format
- Document (PDF)
- Title
- Therapeutic Options for the Treatment of Breast Cancer: Using Cytoreg and Genistein Isoflavone.
- Creator
- Johnson, Michelle M., Kumi-Diaka, James, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
In spite the heavy investments in therapeutic research breast cancer still impacts the lives of women globally. The projected incidence of new cases in USA for 2008 is 67,770, with estimated 40,480 deaths. In this study, we investigated the therapeutic efficacy of Cytoreg®-genistein combination treatment on MCF-7 human breast cancer cells. MCF-7 cells were treated with genistein and Cytoreg® single and combination treatments for 24- 48hr; and the chemosensitivity assessed using bioassays:...
Show moreIn spite the heavy investments in therapeutic research breast cancer still impacts the lives of women globally. The projected incidence of new cases in USA for 2008 is 67,770, with estimated 40,480 deaths. In this study, we investigated the therapeutic efficacy of Cytoreg®-genistein combination treatment on MCF-7 human breast cancer cells. MCF-7 cells were treated with genistein and Cytoreg® single and combination treatments for 24- 48hr; and the chemosensitivity assessed using bioassays: Trypan Blue and MTT for cell viability; Ethidium bromide/Rhodamine 123 to assess apoptosis induction; F AM PolyCaspase binding assay for mechanism of action. The overall data indicated dose- and timedependent cell death in the MCF-cells and that apoptosis was the major means of treatmentinduced growth inhibition. There was evidence of Cytoreg®-induced autophagy in the cells. The overall findings indicated that genistein-Cytoreg® combination was more efficacious than either genistein or Cytoreg® alone. Cytoreg® enhanced the phytosensitivity of MCF-7 cells to genistein isoflavone.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00000777
- Subject Headings
- Breast--Cancer--Treatment, Phytochemicals--Physiological effect, Apoptosis--Molecular aspects, Phytoestrogens--Health aspects, Outcome assessment (Medical care)
- Format
- Document (PDF)
- Title
- THE USE OF CHEMICAL CUES BY SARGASSUM SHRIMPS LEANDER TENUICORNIS AND LATREUTES FUCORUM IN ESTABLISHING AND MAINTAINING A SYMBIOSIS WITH SARGASSUM ALGAE.
- Creator
- Frahm, Jaime L., Brooks, Randy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
A mutualistic symbiosis exists between the alga Sargassum spp. and two shrimp species, L. tenuicornis and L. fucorum. But little is known about how the shrimp locate their host alga. Both visual and chemical cues are potentially available. Visual cues would be presumably restricted at night but chemical cues are potentially available continuously. Additionally, a previous study has looked at both cue variables with results that are mixed. This current research elaborates on the previous study...
Show moreA mutualistic symbiosis exists between the alga Sargassum spp. and two shrimp species, L. tenuicornis and L. fucorum. But little is known about how the shrimp locate their host alga. Both visual and chemical cues are potentially available. Visual cues would be presumably restricted at night but chemical cues are potentially available continuously. Additionally, a previous study has looked at both cue variables with results that are mixed. This current research elaborates on the previous study in an attempt to fully understand Sargassum shrimp chemoreception. A y-maze and four-chambered apparatus were used to test if the shrimp were able to detect Sargassum cues, conspecific cues, and Dimethylsulfoniopropionate (DMSP) cues. Neither shrimp species showed a strong directional response to any of the chemical cues, but the Sargassum and DMSP cues did cause more shrimp to exhibit searching behavior. Additionally, several differences in response between male and female shrimp were found for each cue. A weaker dilution of DMSP was tested in an attempt to determine sensitivity of L. fucorum shrimp to the chemical cue. This weaker dilution also caused L. fucorum to exhibit searching behavior, but the sensitivity to the cue was not found and further research is needed to fully answer this question. These results show the shrimp are able to detect chemical cues in their environment and help determine more accurately the role of chemoreception in initiating and maintaining this shrimp/algal association.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013308
- Subject Headings
- Sargassum, Symbiosis, Shrimps, Leander (Crustacea), Hippolytidae
- Format
- Document (PDF)
- Title
- THE TRIFECTA: A NOVEL COMBINATORIAL THERAPY SPARES IMMUNE CELLS WHILE INDUCING IMMUNOGENIC CELL DEATH IN HUMAN MAMMARY ADENOCARCINOMA AND MOUSE MAMMARY CARCINOMA.
- Creator
- Motii, Youssef, Hartmann, James X., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
According to U.S. Breast Cancer Statistics, about 1 in 8 U.S. women will develop invasive breast cancer during their lifetime. Chemotherapeutics that are used on patients currently often lead to tumor resistance, bone marrow suppression and cachexia. This study evaluated a novel combination of three non-mutagenic compounds for their effectiveness against mammary tumor cells, toxicity towards immune cells, ability to provoke the expression of immunogenic cell death (ICD) markers, and killing...
Show moreAccording to U.S. Breast Cancer Statistics, about 1 in 8 U.S. women will develop invasive breast cancer during their lifetime. Chemotherapeutics that are used on patients currently often lead to tumor resistance, bone marrow suppression and cachexia. This study evaluated a novel combination of three non-mutagenic compounds for their effectiveness against mammary tumor cells, toxicity towards immune cells, ability to provoke the expression of immunogenic cell death (ICD) markers, and killing in 3D tumor models. Methotrexate (MTX), 2-deoxyglucose (2DG), and wogonin (WGN) were combined at doses well below their EC50 values yet effectively killed human and mouse breast cancer cells. The combination inhibited cancer cell colony formation and induced a high degree of cell death in multiple malignant tumor cell lines. Importantly, the combination did not significantly inhibit the viability of peripheral-blood mononuclear cells (PBMCs), even when employed at 3X the concentration that killed cancer cells. In marked contrast, low-dose doxorubicin, a common therapeutic for breast cancers, significantly decreased PBMC viability and increased the percentage of cell death. Our novel combinatorial therapy (Trifecta) elicited the significant expression of three ICD hallmarks: calreticulin surface expression, ATP secretion, and HMGB-1 release. In all cases, Trifecta elicited an equal or greater degree of ICD-marker expression compared to doxorubicin, a known inducer of ICD. We show significant efficacy of Trifecta against human and mouse mammary 3D tumor models grown in Matrigel® ECM-complex containing culture medium, and reaffirm the marked resistance of tumorspheres towards the conventional chemotherapeutic doxorubicin. The effectiveness of Trifecta in an acceptable surrogate model for mouse studies bodes well for translation of our findings to the clinic. In conclusion, Trifecta has proven highly effective against tumor cells grown either as monolayers or tumorspheres, without significant cytotoxic effects towards proliferating immune cells. Furthermore, treatment with this combination elicits ICD, which has the potential to prime an adaptive immune response against tumor cells and prevent future relapse. The drugs chosen for our combination target metabolic pathways that cancer cells are heavily dependent upon and do not interact with or induce mutations in DNA. These properties place Trifecta at the forefront of developing anticancer therapies.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013606
- Subject Headings
- Cancer--Treatment, Breast--Cancer, Methotrexate, Deoxyglucose, wogonin
- Format
- Document (PDF)
- Title
- The Role Of Disturbance In The Genotypic And Morphological Diversity Of Halodule Wrightii.
- Creator
- Tiling, Kathryn A., Proffitt, C. Edward, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Seagrasses are important foundation species in coastal ecosystems. Genetic diversity of seagrasses can influence a number of ecological factors including, but not limited to, disturbance resistance and resilience. Seagrasses in the Indian River Lagoon (IRL), Florida are considered to be highly disturbed due to frequent events, like algal blooms, that impair water quality, reducing available light for seagrass growth. Halodule wrightii is a dominant seagrass throughout the IRL, but its genetic...
Show moreSeagrasses are important foundation species in coastal ecosystems. Genetic diversity of seagrasses can influence a number of ecological factors including, but not limited to, disturbance resistance and resilience. Seagrasses in the Indian River Lagoon (IRL), Florida are considered to be highly disturbed due to frequent events, like algal blooms, that impair water quality, reducing available light for seagrass growth. Halodule wrightii is a dominant seagrass throughout the IRL, but its genetic diversity has only been quantified in a few Gulf of Mexico and Florida Bay populations and little is known about its potential ecological consequences. I quantified the genetic variation of H. wrightii using microsatellite markers in the southern IRL to determine: (i) how disturbance history influenced genetic diversity, (ii) if morphology of clones was, in part, genetically controlled and related to disturbance history, and (iii) if genotypes showed phenotypic plasticity in response to disturbances. In the IRL, H. wrightii populations exhibited moderate genetic diversity that varied with disturbance history. The disturbance history of a population was classified by the variance in the percent occurrence of H. wrightii over a 16-year period. Genotypic richness and clonal diversity of H. wrightii increased with increasing disturbance histories. Other genetic diversity measures (e.g., allelic richness, observed heterozygosity) did not change with disturbance history. These findings suggest that impacts to seagrass coverage over time can change the genotypic composition of populations. When different genotypes of H. wrightii were grown in a common garden, differences in leaf characteristics among genotypes provided evidence that morphological trait variation is, in part, explained by genetic variance. The disturbance history of genotypes did not directly affect morphological traits. However, significant genotype x site (within disturbance history) interactions found greater variation in shoot density and below ground traits of H. wrightii genotypes from sites of intermediate disturbance history. Traits of H. wrightii were shown to be phenotypically plastic. Significant genotype x environment interactions for shoot density and height demonstrated that genotypes responded differently by increasing, decreasing, and not changing sizes in response to light reduction. Genetic diversity of H. wrightii has strong implications for ecological function in coastal communities.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004661, http://purl.flvc.org/fau/fd/FA00004661
- Subject Headings
- Indian River (Fla. : Lagoon) -- Enviornmental conditions, Indian River Lagoon National Estuary Program (Fla.), Marine ecology -- Florida -- Indian River (Lagoon), Restoration ecology, Seagrasses -- Florida -- Indian River (Lagoon), Seagrasses -- Physiology
- Format
- Document (PDF)
- Title
- The Role of Chemical Cues in Locating Pelagic Sargassum by the Associated Fish Stephanolepis hispidus.
- Creator
- Cox, Derek, Brooks, W. Randy, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis...
Show moreThe ecosystem created by pelagic Sargassum is important in the life histories of a number of economically and ecologically important associated organisms. Fishes play a vital role in this food web and nutrient flow within these systems, but it is unknown how they locate these floating habitats. This study examined the role of natural chemical cues from Sargassum patches and the synthetic chemical Dimethylsulfonionpropionate (DMSP) for an associated fish, the planehead filefish (Stephanolepis hispidus) and a control fish species not associated with Sargassum, the masked goby (Coryphopterus personatus). Choice trials with a Y-maze apparatus determined that S. hispidus responded significantly to chemical cues from Sargassum while C. personatus did not. DMSP cues did not result in any significant behavioral responses for either fish. Demonstrating that S. hispidus can respond to chemical cues from Sargassum helps further our understanding of this unique floating algal reef and how fishes may locate it.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004684, http://purl.flvc.org/fau/fd/FA00004684
- Subject Headings
- Animal behavior, Habitat (Ecology), Marine algae, Marine chemical ecology, Predation (Biology), Sargassum -- Ecology
- Format
- Document (PDF)
- Title
- The role of BDNF in the survival and morphological development of adult-born olfactory neurons.
- Creator
- McDole, Brittnee, Guthrie, Kathleen, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Olfactory Granule cells (GCs) are a population of inhibitory interneurons responsible for maintaining normal olfactory bulb (OB) function and circuitry. Through dendrodendritic synapses with the OBs projection neurons, the GCs regulate information sent to the olfactory cortices. Throughout adulthood, GCs continue to integrate into the OB and contribute to olfactory circuitry. However, only ~50% will integrate and survive longterm. Factors aiding in the survival and morphological development...
Show moreOlfactory Granule cells (GCs) are a population of inhibitory interneurons responsible for maintaining normal olfactory bulb (OB) function and circuitry. Through dendrodendritic synapses with the OBs projection neurons, the GCs regulate information sent to the olfactory cortices. Throughout adulthood, GCs continue to integrate into the OB and contribute to olfactory circuitry. However, only ~50% will integrate and survive longterm. Factors aiding in the survival and morphological development of these neurons are still being explored. The neurotrophin brain-derived neurotrophic factor (BDNF) aids in the survival and dendritic spine maturation/maintenance in several populations of CNS neurons. Investigators show that increasing BDNF in the adult-rodent SVZ stimulates proliferation and increases numbers of new OB GCs. However, attempts to replicate these experiments failed to find that BDNF affects proliferation or survival of adult-born granule cells (abGCs). BDNFs regulation of dendritic spines in the CNS is well characterized. In the OB, absence of BDNF’s receptor on abGCs hinders normal spine development and demonstrates a role for BDNF /TrkB signaling in abGCs development. In this study, we use transgenic mice over-expressing endogenous BDNF in the OB (TgBDNF) to determine how sustained increased in BDNF affect the morphology of olfactory GCs and the survival and development of abGCs. Using protein assays, we discovered that TgBDNF mice have higher BDNF protein levels in their OB. We employed a Golgi-cox staining technique to show that increased BDNF expression leads to an increase in dendritic spines, mainly the mature, headed-type spine on OB GCs. With cell birth-dating using 5-bromo-2’- deoxyuridine (BrdU), immunofluorescent cell markers, TUNEL staining and confocal microscopy, we demonstrate that over-expression of BDNF in the OB does not increase survival of abGCs or reduce cell death in the GC population. Using virally labeled abGCs, we concluded that abGCs in TgBDNF mice had similar integration patterns compared to wild-type (WT) mice, but maintained increases in apical headed-type spine density from 12 to 60 days PI. The evidence combined demonstrates that although increased BDNF does not promote cell survival, BDNF modifies GC morphology and abGC development through its regulation of dendritic spine development, maturation and maintenance in vivo.
Show less - Date Issued
- 2018
- PURL
- http://purl.flvc.org/fau/fd/FA00013159
- Subject Headings
- Brain-Derived Neurotrophic Factor, Olfactory Bulb, Olfactory Pathways, Neurons
- Format
- Document (PDF)
- Title
- The role of air and waterborne odors in orientation and food detection in three species of marine turtles.
- Creator
- Kedzuf, Stephanie C., Salmon, Michael, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
The cues used by marine turtles to locate foraging areas in the open ocean are largely unknown though some species (especially the green turtle [Chelonia mydas], the loggerhead [Caretta caretta], and the leatherback [Dermochelys coriacea]) somehow locate areas of high productivity. Loggerheads can detect airborne odors, but a capacity to orient has not yet been investigated. In this comparative study, tethered loggerheads and leatherbacks were exposed to dimethyl sulfide (DMS) or food odors...
Show moreThe cues used by marine turtles to locate foraging areas in the open ocean are largely unknown though some species (especially the green turtle [Chelonia mydas], the loggerhead [Caretta caretta], and the leatherback [Dermochelys coriacea]) somehow locate areas of high productivity. Loggerheads can detect airborne odors, but a capacity to orient has not yet been investigated. In this comparative study, tethered loggerheads and leatherbacks were exposed to dimethyl sulfide (DMS) or food odors in a laminar flow of air. Turtles did not orient into the air current. Free-swimming loggerheads and green turtles were also exposed to air- or waterborne food (squid) odor plus a neutral visual stimulus. Both species showed increases in swimming activity and biting behavior to both stimuli. These results suggest that airborne odors are likely not used to locate distant areas, but that they are used in localized food searching efforts.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004296
- Subject Headings
- Animal behavior, Animal orientation, Population genetics, Predation (Biology), Sea turtles -- Habitat, Sea turtles -- Life cycles, Wildlife conservation
- Format
- Document (PDF)
- Title
- The physiological effects of Sargassum beach coverage on three species of sea turtle hatchlings.
- Creator
- Chaney, Abigail, Milton, Sarah L., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
Sea turtle hatchlings face a variety of obstacles as they crawl down the beach to the ocean after emergence. One of these obstacles is Sargassum, a floating brown macroalgae, that washes up in large quantities on beaches from Florida to South America. This study examined the physiological response and physical performance of three species of sea turtle hatchlings (D. coriacea, C. caretta, and C. mydas) after crawling over various heights of Sargassum. In all three species, the addition of...
Show moreSea turtle hatchlings face a variety of obstacles as they crawl down the beach to the ocean after emergence. One of these obstacles is Sargassum, a floating brown macroalgae, that washes up in large quantities on beaches from Florida to South America. This study examined the physiological response and physical performance of three species of sea turtle hatchlings (D. coriacea, C. caretta, and C. mydas) after crawling over various heights of Sargassum. In all three species, the addition of Sargassum significantly increased the amount of time it took to crawl down the pathway. There was no significant difference in righting response, blood glucose levels, or plasma corticosterone concentrations between different crawling treatments. During periods of high Sargassum accumulation, hatchlings will spend more time on the beach trying to navigate through the algae, leaving them vulnerable to predation for longer periods of time.
Show less - Date Issued
- 2022
- PURL
- http://purl.flvc.org/fau/fd/FA00013939
- Subject Headings
- Sea turtles, Sargassum, Sea turtles--Ecology
- Format
- Document (PDF)
- Title
- The Occurrence of Vibrio vulnificus, V. parahaemolyticus and V. cholerae in the Indian River Lagoon, Florida, with Implications for Human Health.
- Creator
- Barbarite, Gabrielle M., McCarthy, Peter J., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Vibrio bacteria are emerging pathogens responsible for 80,000 illnesses and 100 deaths in the United States each year. Infections are directly linked to the marine environment and are acquired by consuming contaminated seafood or exposing wounds during aquatic activities. Florida has the highest national incidence of vibriosis, with 20% of its cases reported from the Indian River Lagoon region, a popular recreation destination. This study utilized a combination of cultivation and molecular...
Show moreVibrio bacteria are emerging pathogens responsible for 80,000 illnesses and 100 deaths in the United States each year. Infections are directly linked to the marine environment and are acquired by consuming contaminated seafood or exposing wounds during aquatic activities. Florida has the highest national incidence of vibriosis, with 20% of its cases reported from the Indian River Lagoon region, a popular recreation destination. This study utilized a combination of cultivation and molecular techniques to investigate the local distribution of V. vulnificus, V. parahaemolyticus and V. cholerae in this local waterway. The targeted species were found in an array of samples which may facilitate their transmission to humans. Overall, these bacteria were abundant in estuarine sediments (Vp: 2,439 CFU/g, Vv: 303 CFU/g, Vc: 176 CFU/g), on the sharp edges of oyster shells (Vp: 82 CFU/cm, Vv: 102 CFU/cm, Vc: 41 CFU/cm), and in the water column (Vp: 3.78 CFU/ml, Vv: 5.51 CFU/ml, Vc: 2.46 CFU/ml). Vibrio also pose a hazard to recreational anglers as they were recovered from fish (Vp: 61%, Vv: 55%, Vc: 30%), live bait shrimp (Vp: 80%, Vv: 37%, Vc: 0%) and hooks (Vp: 32%, Vv: 18%, Vc: 0%). Additionally, a molecular analysis of the V. vulnificus virulence revealed that the local population was dominated by disease-causing (vcgC) strains, which may explain why wound-related infections are common in this region. Vibrio occurrence varied both spatially and temporally due to their relationship with salinity and temperature. These bacteria exhibited a strong negative correlation with salinity, being particularly abundant near freshwater discharge locations. Due to Florida’s year-round warm climate, these species were found to be permanent members of the local microbial community. Seasonal peaks in abundance occurred between August and October, a period which corresponds with the warmest water temperatures as well as frequent rainfall. Predictive models were constructed based on these parameters to provide a better understanding of how, when and where Vibrio spp. may be encountered by humans. This information is important for both water management and healthcare initiatives, with an overall goal of improving local recreational safety.
Show less - Date Issued
- 2016
- PURL
- http://purl.flvc.org/fau/fd/FA00004705
- Subject Headings
- Health risk assessment, Marine microbiology, Pathogenic microorganisms, Vibrio infections, Vibrionaceae
- Format
- Document (PDF)
- Title
- The multiple stress gradient hypothesis: expansion of the revised stress gradient hypothesis using a mangrove and salt marsh study system.
- Creator
- Coldren, Glenn A., Proffitt, C. Edward, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Plant interactions (e.g., competition, facilitation) are critical drivers in community development and structure. The Stress Gradient Hypothesis (SGH) provides a predictive framework for how plant species interactions vary inversely across an environmental stress gradient, predicting that facilitation is stronger with increasing levels of stress. The SGH has been supported in numerous ecosystems and across a variety of stress gradients, but recent research has demonstrated contradictory...
Show morePlant interactions (e.g., competition, facilitation) are critical drivers in community development and structure. The Stress Gradient Hypothesis (SGH) provides a predictive framework for how plant species interactions vary inversely across an environmental stress gradient, predicting that facilitation is stronger with increasing levels of stress. The SGH has been supported in numerous ecosystems and across a variety of stress gradients, but recent research has demonstrated contradictory results. These discrepancies have led to SGH revisions that expand its conceptual framework by incorporating additional factors, such as other stressor types and variations in species life history strategies. In this dissertation, I examine a further modification of the SGH by proposing and testing a Multiple Stress Gradient Hypothesis (MSGH) that considers how plant interactions vary along a continuous gradient of two co-occurring stressors using mangrove and salt marsh communities as a case study. In Chapter 1, I outline the predictive framework of a MSGH, by creating a series of predictions of species interactions. The components of the MSGH predict that stressors of similar types (e.g., resource and nonresource) will have similar effects and be additive. On the other hand, varying species life history strategies and life stages will lead to extremes of plant interactions. In Chapter 2, I performed a series of experiments to test the various components of the MSGH. In Chapter 3, I performed a large-scale observational study to test whether multiple co-occurring stressors altered the cumulative effects on plant interactions, and if these stressors should be grouped (e.g., resource and non-resource, abiotic and biotic, etc.) to enhance predictability. From a series of studies conducted herein, I concluded that co-occurring stressors are important factors that control complex species interactions as shown in my MSGH modeling approach. Further, future theories need to incorporate species-specific and stressor specific grouping when modeling how species interactions shape communities.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004011
- Subject Headings
- Coastal ecology, Ecophysiology, Mangrove ecology, Plant ecology, Salt marsh ecology
- Format
- Document (PDF)
- Title
- The impacts of nest microenvironment on sea turtle hatchling performance and their responses to thermal stress.
- Creator
- Seaman, Heather A., Milton, Sarah, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
-
As climate change threatens with sea-level rise and more storms, increased erosion could increase the need for beach nourishment. Alterations to sand characteristics may result in changes to the sea turtle nest microenvironment, impacting the temperature and oxygen levels which may affect hatchling performance. In this study, leatherback, loggerhead, and green nests were sampled from two sites with different sand characteristics in Juno Beach, Florida, USA. Gas exchange was higher in green...
Show moreAs climate change threatens with sea-level rise and more storms, increased erosion could increase the need for beach nourishment. Alterations to sand characteristics may result in changes to the sea turtle nest microenvironment, impacting the temperature and oxygen levels which may affect hatchling performance. In this study, leatherback, loggerhead, and green nests were sampled from two sites with different sand characteristics in Juno Beach, Florida, USA. Gas exchange was higher in green turtle nests with a greater mixture of sediment. Darker sediment elevated nest temperatures. Finer sediment and a greater mixture of sediment in leatherback nests elevated the nest temperatures; conversely finer sediment, and a greater mixture of sediment decreased loggerhead and green nest temperatures. Elevated nest temperatures reduced leatherback, loggerhead, and green turtle hatchling performance. Understanding the relationships between beach composition, nest environment, and hatchling performance will aid management decisions essential to sea turtle conservation.
Show less - Date Issued
- 2020
- PURL
- http://purl.flvc.org/fau/fd/FA00013542
- Subject Headings
- Sea turtles--Nests, Thermal stress (Biology), Sea turtles--Conservation, Beach nourishment
- Format
- Document (PDF)
- Title
- The impact of willow encroachment on water and carbon exchange in the vegetation of a subtropical wetland.
- Creator
- Budny, Michelle L., Benscoter, Brian, Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Shortened periods of inundation due to water management have led to the encroachment and expansion of Carolina willow (Salix caroliniana) in sawgrass (Cladium jamaicense) marsh communities. Morphologic and physiologic differences between sawgrass and willow have potential consequences for microhabitat conditions and ecosystem function such as a reduction in temperatures and light availability and changes in primary productivity. Since it is a woody shrub, willow is often assumed to exhibit...
Show moreShortened periods of inundation due to water management have led to the encroachment and expansion of Carolina willow (Salix caroliniana) in sawgrass (Cladium jamaicense) marsh communities. Morphologic and physiologic differences between sawgrass and willow have potential consequences for microhabitat conditions and ecosystem function such as a reduction in temperatures and light availability and changes in primary productivity. Since it is a woody shrub, willow is often assumed to exhibit higher rates of transpiration than non woody plants, which in turn can affect photosynthesis and carbon exchange and ultimately wetland water management. In this study willow was found to have higher rates of stomatal conductance (gs) and photosynthesis (Anet) than sawgrass. However, sawgrass had greater intrinsic water use efficiency (WUE) than willow. This suggests that willow is capable of greater gas exchange and carbon assimilation than sawgrass but requires more water. Understanding the implications of willow expansion will improve landscape models of wetland water and carbon exchange and inform water management decisions.
Show less - Date Issued
- 2015
- PURL
- http://purl.flvc.org/fau/fd/FA00004350, http://purl.flvc.org/fau/fd/FA00004350
- Subject Headings
- Biogeochemistry, Ecosystem management, Surfaces (Technology) -- Measurement, Vegetation dynamics, Wetland ecology
- Format
- Document (PDF)
- Title
- The Impact of Pharmacological Targeting of Abnormal Tumor Metabolism with 3-Bromopyruvate on Dendritic Cell Mediated Tumoral Immunity.
- Creator
- Lang, Kevin, Hartmann, James X., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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Studies have shown that tumor cells are susceptible to pharmacological targeting of their altered glycolytic metabolism with a variety of compounds that result in apoptosis. One such compound, 3-bromopyruvate (3-BP), has been shown to eradicate cancer in an animal model. However, no studies have shown whether the apoptotic fragments resulting from 3-BP treatment have the capacity to elicit an immunogenic cell death that activates dendritic cells, the primary antigen presenting cell in the...
Show moreStudies have shown that tumor cells are susceptible to pharmacological targeting of their altered glycolytic metabolism with a variety of compounds that result in apoptosis. One such compound, 3-bromopyruvate (3-BP), has been shown to eradicate cancer in an animal model. However, no studies have shown whether the apoptotic fragments resulting from 3-BP treatment have the capacity to elicit an immunogenic cell death that activates dendritic cells, the primary antigen presenting cell in the immune system. Immunogenic cell death is critical to eliciting an effective adaptive immune response that selectively kills additional target cells and generates immunological memory. We demonstrated that 3-bromopyruvate induced apoptosis in a number of different murine breast cancer cell lines, including the highly metastatic 4T1 line. The dying tumor cells stimulated immature dendritic cells (DCs) of the immortal JAWS II cell line to produce high levels of the pro-inflammatory cytokine IL-12, and increased their expression of key co-stimulatory molecules CD80 and CD86. The activated dendritic cells showed increased uptake of fragments from dying tumor cells that correlated with the increased levels of calreticulin on the surface and release of high group motility box 1 (HMGB1) of the latter following 3-BP treatment. Additionally, the anti-phagocytic signal CD47 present on breast cancer cells was reduced by treatment with 3-bromopyruvate when compared to the levels on untreated 4T1 cells. 3-BP treated breast cancer cells were able to activate dendritic cells through TLR4 signaling. Signaling was dependent on both the expression of surface calreticulin and on the extracellular release of high mobility group box 1 protein (HMGB1) during the process of immunogenic cell death. Killing by 3-BP was compared to mitoxantrone and doxorubicin, among the few chemotherapeutics that induce immunogenic cell death. 3-BP killing was likewise compared to camptothecin, a compound that fails to induce immunogenic cell death. Importantly, 3-BP did not markedly decrease the levels of the key peptide presenting molecule MHC I on DCs that were co-cultivated with dying tumor cells. Treatment of the highly aggressive triple negative BT-20 human breast cancer cell line with 3-BP also induced an immunogenic cell death, activating human dendritic cells in vitro.
Show less - Date Issued
- 2017
- PURL
- http://purl.flvc.org/fau/fd/FA00004834
- Subject Headings
- Apoptosis., Cellular signal transduction., Cell death., Breast--Cancer--Treatment., Carrier proteins., Cancer--Molecular aspects., Biological interfaces.
- Format
- Document (PDF)
- Title
- THE IMPACT OF NUTRIENT LOADING ON THE SOIL AND ROOT RESPIRATION RATES OF FLORIDA MANGROVES.
- Creator
- Faron, Natalie Therese, Benscoter, Brian, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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Coastal nutrient loading is a growing concern in urbanized communities and has led to alterations in above- and belowground processes throughout estuarine systems. Mangrove forests are highly productive coastal habitats that exhibit large carbon stocks contained mostly to the deep soils. Since nutrient enrichment has been found to increase mangrove aboveground growth, it’s presumed that nutrient enrichment will also increase belowground respiration rates. Disturbances in soil nutrient content...
Show moreCoastal nutrient loading is a growing concern in urbanized communities and has led to alterations in above- and belowground processes throughout estuarine systems. Mangrove forests are highly productive coastal habitats that exhibit large carbon stocks contained mostly to the deep soils. Since nutrient enrichment has been found to increase mangrove aboveground growth, it’s presumed that nutrient enrichment will also increase belowground respiration rates. Disturbances in soil nutrient content may alter the mangrove carbon cycle by increasing the amount of CO2 lost to the atmosphere from enhanced microbial and root respiration. In this study, soil respiration responded greatest to nitrogen enrichment, but pneumatophore root respiration responded greatest to phosphorus enrichment. Nutrient limitation can shift between different ecological processes and responses to nutrient enrichment tend to be system specific in tidally influenced ecosystems. Understanding the implications of coastal nutrient loading will improve ecosystem models of carbon exchange and belowground processes.
Show less - Date Issued
- 2021
- PURL
- http://purl.flvc.org/fau/fd/FA00013767
- Subject Headings
- Mangrove forests, Soil respiration, Carbon cycle (Biogeochemistry)
- Format
- Document (PDF)
- Title
- THE IMPACT OF ENVIRONMENTAL FACTORS ON LOGGERHEAD SEA TURTLE (CARETTA CARETTA) HATCHLING BIOLOGY.
- Creator
- Lolavar, Alexandra A., Wyneken, Jeanette, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
- Abstract/Description
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The eggs of all sea turtle species develop in underground nests on oceanic nesting beaches. Eggs are unattended and their incubation conditions are subject to effects of the environment. Nest temperature influences various aspects of hatchling biology, including sex determination. Past studies identified that sea turtle embryos have a warm female cool male response pattern and rainfall has been thought to cool nest temperature. The effects of rainfall or periods of drought were often inferred...
Show moreThe eggs of all sea turtle species develop in underground nests on oceanic nesting beaches. Eggs are unattended and their incubation conditions are subject to effects of the environment. Nest temperature influences various aspects of hatchling biology, including sex determination. Past studies identified that sea turtle embryos have a warm female cool male response pattern and rainfall has been thought to cool nest temperature. The effects of rainfall or periods of drought were often inferred but not verified. Using laboratory and field studies, I examined how changes in environmental factors during incubation, particularly sand moisture, can affect nest conditions and hatchling biology. I derived temperature-sex ratio response curves for eggs incubated at different moisture levels to determine the effect of moisture on how embryos respond to temperature. I also studied how increasing moisture levels in relocated nests through daily watering influence nest conditions and discuss if this method is an effective mitigation strategy for the detrimental effects of increasing temperatures on embryo survival and sex ratios. I investigated how environmental factors, nest conditions, and hatchling biology can differ among sites on a nesting beach. Extreme moisture conditions, both low and high, result in a narrower transition between one sex ratio bias to another. I demonstrated that watering nests decreases nest temperatures and increases hatching success but watering has a minimal impact on sex ratios. Ambient beach conditions vary slightly in air temperature, rainfall, solar radiation, and humidity, depending on beach location. Nest conditions such as nest temperature and moisture also differ, but hatching success and sex ratios do not vary among different sites on the same nesting beach in Boca Raton, Florida. Ultimately, these studies together help identify and demonstrate how these environmental factors and drivers can affect the nest environment during incubation. Further developing our understanding of environmental factors, particularly nest moisture, and their variability will provide better predictions of future climate change effects and perhaps create more effective mitigation strategies.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013390
- Subject Headings
- Loggerhead turtle, Sea turtles--Nests, Environment, Eggs--Hatchability, Eggs--Incubation, Moisture
- Format
- Document (PDF)
- Title
- The hawksbill rookery at Antigua, W.I.: nest success, hatchling behavior, and hatchling survival during offshore migration.
- Creator
- Reising, Megan, Salmon, Michael, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
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The younger life history stages of marine turtles (eggs, hatchlings) often fail to survive. To compensate, sea turtles nest several times/season and produce large clutches of eggs. The hawksbill produces the largest clutches (150 eggs) and the smallest hatchlings of any marine turtle. My study, done at Jumby Bay in Antigua, West Indies, was designed to determine whether they did so to compensate for loss in the nest, hatchling loss in the water, or both factors. I found that most of the eggs ...
Show moreThe younger life history stages of marine turtles (eggs, hatchlings) often fail to survive. To compensate, sea turtles nest several times/season and produce large clutches of eggs. The hawksbill produces the largest clutches (150 eggs) and the smallest hatchlings of any marine turtle. My study, done at Jumby Bay in Antigua, West Indies, was designed to determine whether they did so to compensate for loss in the nest, hatchling loss in the water, or both factors. I found that most of the eggs (79 %) survived to become hatchlings that left the nest and entered the sea. However, 88 % of the hatchlings swimming offshore were taken by predators within minutes after they began their migration. These results suggest that at Jumby Bay, large clutch size is favored in hawksbills because of predation pressures on the hatchlings.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fau/fd/FA0004049
- Subject Headings
- Animal migration -- Antigua -- Jumbo Bay, Animal orientation -- Antigua -- Jumbo Bay, Hawksbill turtle -- Research -- Antigua -- Jumbo Bay, Predation (Biology), Sea turtles -- Research -- Antigua -- Jumbo Bay, Wildlife conservation -- Antigua -- Jumbo Bay
- Format
- Document (PDF)
- Title
- The Functional Morphology of Shark Control Surfaces: A Comparative Analysis.
- Creator
- Hoffmann, Sarah Louise, Porter, Marianne E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
- Abstract/Description
-
Sharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded...
Show moreSharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded rostrum of saw shark species representing some of the anatomical extremes. Yet despite these obvious differences in morphology, physiology, and ecology, the challenges associated with studying hard to access, large bodied, pelagic animals have limited our comparative understanding of form and function as it relates to swimming within this group. The majority of shark swimming studies examine species that succeed in captivity, which are usually benthic associated sharks that spend time resting on the substrate. These studies have also been limited by the use of flumes, in which the unidirectional flow and small working area precludes the analysis of larger animals, volitional swimming, and maneuvering. The few existing volitional kinematics studies on sharks quantify two-dimensional kinematics which are unable to capture movements not observable in the plane of reference. With this study, we quantified the volitional swimming kinematics of sharks in relation to morphological, physiological, and ecological variation among species. We developed a technique to analyze three-dimensional (3D) kinematics in a semi-natural, large volume environment, which, to our knowledge, provides the first3D analysis of volitional maneuvering in sharks. We demonstrated that Pacific spiny dogfish and bonnethead sharks rotate the pectoral fins substantially during yaw (horizontal) maneuvering and is correlated with turning performance. We proposed that ecomorphological differences correlate with the varied maneuvering strategies we observed between the two species. We also found that there is some mechanical constraint on shark pectoral fin shape that is explained by phylogenetic relationships but describe a continuum of morphological variables within that range. We propose standardized terminology and methodology for the future assessment of shark pectoral fin morphology and function. As with previous studies, the ease of access to species was a challenge in this study and future studies should continue to assess the functional ecomorphology of shark pectoral fins among species.
Show less - Date Issued
- 2019
- PURL
- http://purl.flvc.org/fau/fd/FA00013217
- Subject Headings
- Sharks, Morphology (Animals), Kinematics
- Format
- Document (PDF)