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- Title
- SWIM PERFORMANCE VARIABILITY OF THREE SPECIES OF JUVENILE ELASMOBRANCHS AND ITS RELATIONSHIP TO PREDATOR AVOIDANCE.
- Author
- Wilborn, Rachel Elizabeth, Bennett, Wayne A., Smith, David J., Ryals, Phillip E., University of West Florida
- Abstract/Description
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Maximum swimming velocity, oxygen consumption, and plasma lactate levels are useful indicators for evaluating metabolic performance limits in fish. Metabolic costs of exertion, maximum swim velocities, and ventilation rates in juvenile blue-spotted ribbontail stingrays (Taeniura lymma), Atlantic stingrays (Dasyatis sabina), and white-spotted bamboo sharks (Chiloscyllium plagiosum) were quantified. All species showed a decrease in oxygen consumption postexertion, with Atlantic stingrays being...
Show moreMaximum swimming velocity, oxygen consumption, and plasma lactate levels are useful indicators for evaluating metabolic performance limits in fish. Metabolic costs of exertion, maximum swim velocities, and ventilation rates in juvenile blue-spotted ribbontail stingrays (Taeniura lymma), Atlantic stingrays (Dasyatis sabina), and white-spotted bamboo sharks (Chiloscyllium plagiosum) were quantified. All species showed a decrease in oxygen consumption postexertion, with Atlantic stingrays being significantly lower (Independent t-test; P=0.0425). Significantly higher values in plasma lactate were evident in bamboo sharks pre and postexertion (0.02 and 0.35 mmol l-1, respectively); however, values for Atlantic stingrays remained unchanged (0.91 and 0.64 mmol l-1). Atlantic and ribbontail stingrays obtained greater relative speeds (9.224 and 5.163 BL sec-1, respectively) than bamboo sharks (1.060 BL sec-1). In addition, preexertion ventilation rates in Atlantic and ribbontail stingrays were faster than bamboo sharks (71.18, 70.67, 46.75 breaths min-1, respectively), while only Atlantic stingray ventilation rates postexertion differed from either bamboo sharks or ribbontail stingrays (77.69, 62.69, 49.40 breaths min-1, respectively). These data suggest that all three species utilized aerobic metabolism in conjunction with behavioral adaptations as predator avoidance strategies, making minimal use of anaerobic metabolism for locomotion.
Show less - Date Issued
- 2007
- Identifier
- WFE0000083, uwf:60686
- Format
- Document (PDF)
- Title
- SALINITY EFFECT ON UREA AND TMAO LEVELS IN BLOOD PLASMA OF ATLANTIC STINGRAY, DASYATIS SABINA.
- Author
- Ferer, Erin Jennifer, Bennett, Wayne A., Pomory, Christopher, Ryals, Phillip E., University of West Florida
- Abstract/Description
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The range of osmolyte adjustment tolerated by euryhaline species such as the Atlantic stingray has never been quantified. The purpose of my experiments was to determine how salinity affects osmolytes involved in osmoregulation of Atlantic stingray. Plasma osmolality and TMAO and urea concentrations were measured for 50 Atlantic stingrays acclimated at five salinity treatments between 5 and 60. Although Atlantic stingrays in my experiments stopped eating above 50, fish showed the typical...
Show moreThe range of osmolyte adjustment tolerated by euryhaline species such as the Atlantic stingray has never been quantified. The purpose of my experiments was to determine how salinity affects osmolytes involved in osmoregulation of Atlantic stingray. Plasma osmolality and TMAO and urea concentrations were measured for 50 Atlantic stingrays acclimated at five salinity treatments between 5 and 60. Although Atlantic stingrays in my experiments stopped eating above 50, fish showed the typical hyperosmotic pattern at salinities up to 60. Osmolality remained constant (721 mOsm) at salinities below 20 but increased more slowly than ambient salinity above 20. Urea concentrations in my study were consistent with reports for Atlantic stingray and other elasmobranchs. Euryhaline elasmobranch species seem to exhibit a greater capacity for urea retention. Concentrations of TMAO were nearly 45% lower than levels in other elasmobranchs. Although other osmolytes are shown to be important in some elasmobranchs, it is unclear what role they may play for Atlantic stingray. Steady increases in TMAO levels even after fish stopped eating, indicate that TMAO levels are likely controlled by physiology and not diet. Low TMAO values in spite of high urea and osmolality leave open the question of how Atlantic stingrays fill the osmotic deficit.
Show less - Date Issued
- 2007
- Identifier
- WFE0000099, uwf:60712
- Format
- Document (PDF)
- Title
- PHOSPHATIDYLINOSITOL SYNTHASE OF TETRAHYMENA: UTILIZATION OF INOSITOL ISOMERS IN THE HEADGROUP EXCHANGE REACTION.
- Author
- Riggs, Bridget May, Ryals, Phillip E., Fox, Theodore C., Snyder, Richard A., University of West Florida
- Abstract/Description
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Phosphatidylinositol synthase [CDP-diacylglycerol: myo-inositol 3-phosphatidyltransferase, E.C. 2.7.8.11] is present in all eukaryotic cells and some bacterial cells. Predominantly found on the cytoplasmic side of the endoplasmic reticulum, this bifunctional enzyme catalyzes the de novo synthesis of phosphatidylinositol from cytidine diphosphate-diacylglycerol and myo-inositol. The enzyme also catalyzes a headgroup exchange reaction wherein the inositol headgroup of phosphatidylinositol is...
Show morePhosphatidylinositol synthase [CDP-diacylglycerol: myo-inositol 3-phosphatidyltransferase, E.C. 2.7.8.11] is present in all eukaryotic cells and some bacterial cells. Predominantly found on the cytoplasmic side of the endoplasmic reticulum, this bifunctional enzyme catalyzes the de novo synthesis of phosphatidylinositol from cytidine diphosphate-diacylglycerol and myo-inositol. The enzyme also catalyzes a headgroup exchange reaction wherein the inositol headgroup of phosphatidylinositol is exchanged for a different molecule of inositol. Headgroup exchange activity associated with phosphatidylinositol synthase from the protist Tetrahymena was investigated to establish whether isomers of inositol other than myo-inositol are suitable substrates. This investigation revealed that eight of the nine isomers of inositol examined were used as substrates in the headgroup exchange reaction. Furthermore, cytidine monophosphate was shown to be necessary for maximal headgroup exchange activity. These data provide evidence for a mechanism by which novel phosphatidyl-non-myo-inositols can be formed in vivo.
Show less - Date Issued
- 2006
- Identifier
- WFE0000030, uwf:60755
- Format
- Document (PDF)
- Title
- VENOM TOXICITY AND BIOENERGETICS OF THE SPINE FROM ATLANTIC STINGRAY, DASYATIS SABINA.
- Author
- Enzor, Laura Ann, Bennett, Wayne A., Pomory, Christopher M., Ryals, Phillip E., University of West Florida
- Abstract/Description
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Atlantic stingray, Dasyatis sabina, possess a venomous spine thought to be useful in defense. Anecdotal evidence as well as observations of stinging incidents in nature illustrate that these fish are reluctant to use the spine when threatened or attacked, and in cases where the spine is used, it is not an effective predator deterrent. Venomous systems have been shown to be metabolically expensive, raising the question of why stingrays invest in a system that is inadequate for defense. This...
Show moreAtlantic stingray, Dasyatis sabina, possess a venomous spine thought to be useful in defense. Anecdotal evidence as well as observations of stinging incidents in nature illustrate that these fish are reluctant to use the spine when threatened or attacked, and in cases where the spine is used, it is not an effective predator deterrent. Venomous systems have been shown to be metabolically expensive, raising the question of why stingrays invest in a system that is inadequate for defense. This study determines stingray venom toxicity (LC50) and quantifies metabolic costs associated with the venom delivery system. Acute toxicity tests determined a LC50 value of 0.018 mg protein·g fish-1 with the average protein content of 35.71 mg·mL venom-1. Respirometry determined that approximately 0.000162 kcal·g-1·h-1 are devoted to maintenance of venomous tissues and the spine. Caloric density of spines was measured using ballistic bomb calorimetry. The average number of kilo-calories per gram of spine weight was 0.238. Empirical and observational evidence from laboratory and field studies suggest that the spine may serve key roles in reproductive behavior and in establishing social hierarchies as well as defense.
Show less - Date Issued
- 2008
- Identifier
- WFE0000102, uwf:60849
- Format
- Document (PDF)
- Title
- THE EFFECTS OF LITHIUM AND VALPROIC ACID ON THE PHENOTYPIC STATE, PHOSPHORYLATED PROTEOME AND CALCIUM-BINDING PROTEOME OF TETRAHYMENA PATULA.
- Author
- Sprinkel, Katie Connors, Ryals, Phillip E., Fox, Theodore C., Huggins, Michael T., University of West Florida
- Abstract/Description
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The effects of lithium and valproic acid on the phenotypic state of Tetrahymena patula were investigated. As related to the effects on phenotype, the phosphorylated proteome and calcium-binding proteome of T. patula were examined for changes in order to gain insight into the biochemical targets of lithium and valproic acid. Samples taken from various treatments were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Gels were stained with Pro-Q Diamond stain for...
Show moreThe effects of lithium and valproic acid on the phenotypic state of Tetrahymena patula were investigated. As related to the effects on phenotype, the phosphorylated proteome and calcium-binding proteome of T. patula were examined for changes in order to gain insight into the biochemical targets of lithium and valproic acid. Samples taken from various treatments were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis. Gels were stained with Pro-Q Diamond stain for phosphoproteins and Sypro Ruby stain for total proteins in order to discern changes in degree of treatmentdependent protein phosphorylation. Changes were digitally quantified. Separate gels were also stained to visualize any qualitative change in the presence of calcium-binding proteins. Patterns of treatment-dependent morphological changes correlated to changes with an increase in the degree of phosphorylation of a 59 kDa protein and 43 kDa protein. These changes may implicate the involvement of phosphoinositide signaling in the dedifferentiation of T. patula. The changes in the presence of 60 kDa and 115 kDa calcium-binding proteins appeared to be treatment-dependant and related to morphological change.
Show less - Date Issued
- 2011
- Identifier
- WFE0000268, uwf:60893
- Format
- Document (PDF)
- Title
- KETAMINE INCREASES SUSCEPTIBILITY TO INFLUENZA IN MICE.
- Author
- Hemphill, Melissa Ann, Nash, Paul B., Behan, Kristina J., Hahn, Angela M., Ryals, Phillip E., University of West Florida
- Abstract/Description
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Influenza is a constant threat to public health. For this reason, many research hours and dollars have been invested in understanding the virus and how to better protect humans from the sometimes-deadly effects of influenza. BALB/c and C57Bl/6 mice have been common models for studying influenza, and ketamine anesthetization has been commonly used when inoculating mice with influenza. Recent literature indicates that ketamine may be affecting the immune response by interfering with the...
Show moreInfluenza is a constant threat to public health. For this reason, many research hours and dollars have been invested in understanding the virus and how to better protect humans from the sometimes-deadly effects of influenza. BALB/c and C57Bl/6 mice have been common models for studying influenza, and ketamine anesthetization has been commonly used when inoculating mice with influenza. Recent literature indicates that ketamine may be affecting the immune response by interfering with the functional maturation of dendritic cells and other innate immune mediators. This study shows that ketamine increases susceptibility to the H1N1 influenza virus, A/PR/8/34. Most of the effect is shown to be due to the presence of ketamine independent of anesthetization. In this study, TPCK-trypsin parameters were also evaluated in MDCKpropagated influenza. Replenishing trypsin 24 hours post-infection increased the viral titer. MDCK-propagated influenza was also tested for infectivity in multiple cells lines, MDCK, NF-1, Sp2/0-Ag14, and JAWSII. Only MDCK and NF-1 showed influenza growth 48 hours after infection.
Show less - Date Issued
- 2013
- Identifier
- WFE0000396, uwf:61021
- Format
- Document (PDF)
- Title
- ROLE OF SALICYLIC ACID AND ABSCISIC ACID IN THE DEFENSE RESPONSE OF DIOSCOREA BULBIFERA L. TO FUNGAL PATHOGENS.
- Author
- Penabade, Alexander Luis, Fox, Theodore C., Ryals, Phillip E., Lepo, Joe E., University of West Florida
- Abstract/Description
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Plant-microbe interactions occur frequently in nature and can be detrimental to survival of the plant. In order for plants to survive these negative interactions with microbes the plant must recognize and appropriately respond to the attacking pathogen. In the response to pathogen attack signaling molecules are induced to initiate expression of pathogenesis-related proteins. These signaling molecules interact to form a fine tuned defense response to combat different pathogens in different...
Show morePlant-microbe interactions occur frequently in nature and can be detrimental to survival of the plant. In order for plants to survive these negative interactions with microbes the plant must recognize and appropriately respond to the attacking pathogen. In the response to pathogen attack signaling molecules are induced to initiate expression of pathogenesis-related proteins. These signaling molecules interact to form a fine tuned defense response to combat different pathogens in different ways. The defense response in invasive plants has not been well studied. This study focuses on the response to fungal pathogens in an invasive plant (Dioscorea bulbifera L.). Here, two classes of pathogenesis related proteins, PR-2 and PR-3, which are comprised of glucanases and chitinases, were used to monitor the defense response after treatments with fungal elicitor or the signaling molecules salicylic acid and abscisic acid. This study provides evidence that the reproductive tissue has constitutive expression of these pathogenesis related proteins whereas leaves (vegetative tissue) exhibit an induced response to pathogen attack. Further investigation into D. bulbifera L. may elucidate which signaling pathway is involved with the constitutive defense response in reproductive tissue, as well as, the response to fungal pathogens in leaves.
Show less - Date Issued
- 2014
- Identifier
- WFE0000458, uwf:61086
- Format
- Document (PDF)
- Title
- PATHOGENESIS RELATED PROTEINS IN DIOSCOREA BULBIFERA L.: A STUDY OF THE EXPRESSION PATTERNS OF PUTATIVE DEFENSE PROTEINS IN AN INVASIVE PLANT SPECIES.
- Author
- Bradley, Allyson Joy, Fox, Theodore C., Ryals, Phillip E., Huggins, Michael T., University of West Florida
- Abstract/Description
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Plants experience a myriad of diverse stress stimuli, and because they are sessile organisms they have had to evolve intricate defense mechanisms for survival. Defenses include a unique family of proteins called pathogenesis related (PR) proteins. These low molecular weight proteins can be constitutively expressed or highly inducible upon elicitation by fungal pathogens. The signaling pathways that lead to the expression of the PR proteins are regulated by the plant hormones salicylic acid ...
Show morePlants experience a myriad of diverse stress stimuli, and because they are sessile organisms they have had to evolve intricate defense mechanisms for survival. Defenses include a unique family of proteins called pathogenesis related (PR) proteins. These low molecular weight proteins can be constitutively expressed or highly inducible upon elicitation by fungal pathogens. The signaling pathways that lead to the expression of the PR proteins are regulated by the plant hormones salicylic acid (SA), jasmonic acid (JA), and abscisic acid (ABA). Western blot data provide evidence that the PR proteins chitinase and a-1,3-glucanase are present in both leaf and tuber tissues of Dioscorea bulbifera L. Upon treatment of leaf tissue with SA, expression of a 47 kDa chitinase was up regulated after both 24 and 48 hours. Leaves treated with Fusarium graminearum cell wall fragments exhibited a unique triplet of bands with molecular weights of 28, 24, and 16 kDa. Tuber tissues exhibited constitutive expression of a 119 kDa and a 34 kDa chitinase and a 31 kDa a-1,3-glucanase across all treatments. This thesis provides evidence that supports the role of chitinases and a-1,3-glucanases as part of a defense response in aerial tubers and leaves of D. bulbifera L.
Show less - Date Issued
- 2014
- Identifier
- WFE0000459, uwf:61089
- Format
- Document (PDF)
- Title
- LATITUDINAL PATTERNS OF CILIATE RDNA DIVERSITY IN THE SURFACE PLANKTON OF THE PACIFIC OCEAN.
- Author
- Covell, Marthe Adrienne, Caffrey, Jane M., Moss, Joseph A., Jeffrey, Wade H., Ryals, Phillip E., University of West Florida
- Abstract/Description
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Unicellular organisms known as ciliates (Phylum: Ciliophora) are a widespread and ecologically important group of eukaryotic microorganisms. Despite their critical roles in the microbial and planktonic food webs, their global distribution patterns remain poorly understood. It is unclear whether ciliates follow the same latitudinal gradient patterns that have been identified for macroscopic organisms, which generally show an increase in biodiversity and species richness approaching the equator...
Show moreUnicellular organisms known as ciliates (Phylum: Ciliophora) are a widespread and ecologically important group of eukaryotic microorganisms. Despite their critical roles in the microbial and planktonic food webs, their global distribution patterns remain poorly understood. It is unclear whether ciliates follow the same latitudinal gradient patterns that have been identified for macroscopic organisms, which generally show an increase in biodiversity and species richness approaching the equator. Some microbial ecologists believe that ciliates do not have the same types of dispersal limitations as larger organisms and therefore will have ubiquitous distribution, while others argue that there is evidence of endemic species in specialized oceanic environments In this study, ciliate rDNA diversity was examined along a 15,400 km transect of the Pacific Ocean in order to identify distributional patterns. A combination of molecular techniques including terminal restriction fragment length polymorphism (T-RFLP) analysis, molecular cloning, and DNA sequencing were used to document patterns of biodiversity. Statistical analyses show that there is no significant relationship between latitude and ciliate distribution. This study provides a broad understanding of the distribution patterns of marine ciliates, as well as adds to our understanding of the global biogeography of microscopic organisms.
Show less - Date Issued
- 2016
- Identifier
- WFE0000553, uwf:61241
- Format
- Document (PDF)