department of biology senior research symposium...1 department of biology senior research symposium...

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Department of Biology Senior Research Symposium

April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session One: Monday, April 28, 2008 8:30 a.m. Section 01 lab Moderator: Mr. Nourian 8:30 Introduction 8:40 THE IMPACT OF THE INVASIVE SPECIES LONICERA MAACKII ON SOIL NUTRIENT LEVELS Joseph R. Lally, Shannon M. Chambers, Touraj Karkevandian (Dr. Brent Blair) The invasive species Lonicer Maackii (Amur Honeysuckle) is thought to have a competitive advantage over native species in Southern Ohio which accounts for its high distribution. We believe that Honeysuckle alters soil nutrient content and thereby has a competitive advantage over native species. Our group collected soil samples from Honeysuckle infested areas and natural areas in Cincinnati forests to observe potential differences in pH, nitrate and ammonia levels. Honeysuckle demonstrated more acidic soils compared to native soils while the nitrogen tests were inconclusive and need further study. The understanding of how Honeysuckle alters its environment for its own success is important in controlling future invasions of Honeysuckle and other invasive species.

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9:00 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Katherine Bartholomew, Megan K. Farrell, Jennifer L. Frank, Jamie Gentile, Omari Jones-Nelson, Kara Knight, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population. 9:20 EVALUATING THE RELATIONSHIP BETWEEN H2O2-ASSOCIATED OXIDATIVE STRESS AND VON HIPPEL LINDAU (VHL) PROTEIN Danielle Maue, Sarah Gillian, and Ashley Roberts (Dr. Waltke Paulding)

Many environmental factors, including hypoxia, can induce oxidative stress. Cells that are subjected to oxidative stress often generate reactive oxygen species (ROS), which include hydrogen peroxide (H2O2). Familial von Hippel-Lindau (VHL) disease develops in individuals that are born heterotrophic for the wild-type (wt)VHL gene, and who subsequently lose the remaining wt-VHL allele due to mutation. Excessive, unregulated quantities of ROS are known to damage cellular macromolecules, including proteins lipids and nucleic acids. We are currently examining the oxidative status of cells that express (wt-VHL) or lack (mut-VHL) the VHL protein, as a decrease in a cell’s ability to maintain “oxidative homeostasis” may be related to DNA damage, and expression of VHL pathology. Results from experiments in which H2O2 production was measured in VHL(+) or VHL(-) cell lines, under either normoxic (21% O2) or hypoxic (1% O2) conditions, revealed higher, basal amounts of H2O2 in VHL(-) cells in normoxic conditions, as contrasted to VHL(+) cells. Hypoxia reduced production of H2O2 in both VHL(+) and VHL(-) cell lines. Evaluation of expression levels of superoxide dismutase (SOD) and catalase, the 2 main enzymes involved in regulating H2O2 levels in the oxidative stress pathway, continue.

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Department of Biology

Senior Research Symposium

April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Two: Monday, April 28, 2008 10:30 a.m. Section 02 lab Moderator: Mr. Tehrani 10:30 Introduction 10:40 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Emmanuel A. Ofori, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.

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11:00 MEASURING NITROGEN-FIXING ABILITIES OF A RELATIONSHIP BETWEEN WINTER WHEAT (TRITICUM AESTIVUM) AND THE BACTERIUM AZOSPIRILLUM BRASILENSE Katie M. Zak, Maricor K. Docena, (Dr. Linda Finke)

The nitrogen fixing bacteria Azospirillum brasilense can colonize wheat plant roots and provide the plant with essential nitrogen in the form of ammonia. While symbiotic nitrogen fixing relationships are well understood, this experiment explores looser associations such as the one between A. brasilense and winter wheat, which seems to be beneficial to plant growth. Plants were grown hydroponically and the experimental group was inoculated with A. brasilense in the absence of nitrogen in the plant medium. Plants given a complete nitrogen-containing medium and those given a nitrogen-free medium without bacteria served as controls. Plant growth was recorded photographically and by final dry weight. Acetylene reduction assay of plant roots was performed to measure nitrogenase activity, the enzyme responsible for the nitrogen fixing abilities of such bacteria. Preliminary photographic results indicated that positive control plants with nitrogen-containing medium had the best growth while the experimental and second control group appeared the same.

11:20 NON-INVASIVE MEASUREMENT OF FECAL CORTICOSTERONE TO ASSESS STRESS Paul Blair, Jon Salman, Tomilyn Thornberry, and Alexis Wickersham (Dr. Waltke Paulding) Corticosterone is a hormone produced by the adrenal gland that is commonly measured as an indicator of physiological stress. Accurate quantification of corticosterone levels typically requires measuring the hormone in blood plasma and may also require the use of radioisotopes. Because obtaining blood samples from animals is a complicated, stressful process, which likely increases corticosterone production, and use of radioisotopes is hazardous, expensive, and requires special training and authorization, the goal of our project is to develop a non-invasive, non-radioactive method to quantify corticosterone. Fecal samples were obtained from several birds and mice and conditions for measurement of corticosterone using an immunometric assay are being standardized. Once developed, this test will be utilized to quantify the effect of various environmental stressors in mocking birds.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Three: Monday, April 28, 2008 2:30 p.m. Section 03 lab Moderator: Dr. Matre 2:30 Introduction 2:40 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Megan K. Farrell, Katherine Bartholomew, Jennifer L. Frank, Jamie Gentile, Omari Jones-Nelson, Kara Knight, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population.

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3:00 ANALYZING LEAF LITTER DECOMPOSITION RATES OF THE INVASIVE AMUR HONEYSUCKLE WITH NATIVE SPECIES IN SOUTHWESTERN OHIO FORESTS Manuel Alvarez, Joseph Dagher, Maya Webb (Dr. Brent Blair)

The Amur honeysuckle (Lonicera mackii), native to Asia, was introduced to Southwestern Ohio forests in the 1800s, and has become extremely invasive. This multi- stem shrub has begun to dominate the understory of many forests, preventing many native saplings to take root. Leaf litter decomposition rates of the honeysuckle were compared to native species of oak and maple. Litter was collected and air dried, then placed into 15cm x 15cm mesh bags, and placed on the forest floor to decompose. In all situations, the honeysuckle decomposed faster than each of the native species, even when placed on forest floors where honeysuckle was not present. The data support the hypothesis that the Amur honeysuckle leaf litter would have a faster decomposition rate than its native counterparts, affecting soil fertility to enhance its invasiveness in non-native communities. 3:20 VARIATION IN SEASONAL SWIM BEHAVIOR AMONG CAPTIVE FLORIDA MANATEES David N. Phillips, Cody Dangelser, Anthony Kurian (Dr. Charles Grossman) This study attempted to analyze the swim behavior of captive Florida manatees throughout the four seasons of the calendar year. In the wild, Florida manatees will swim more frequently during the summer months as food is plentiful and the water temperature is high. However, wild manatees’ swimming activity decreases greatly as the temperature declines in the winter months. The alternative habitat provided by the Cincinnati Zoo, with consistent environmental features, was expected to cause the captive manatees to deviate from their natural swimming behaviors. The manatees traversed an average of 12.3 blocks per run during the summer months of June, July, and August while navigating an average of 3.4 blocks per run during the winter months of December, January, and February. Though more data seems to be necessary, from the current results found, it can be concluded as of now, the captive manatees; swim behavior is similar to those in the wild.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Four: Monday, April 28, 2008 4:30 p.m. Section 04 lab Moderator: Mr. Pecquet 4:30 Introduction 4:40 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Charles A. Gabis, Jacqueline K. Baker, Nilay J. Choksi, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.








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5:00 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Jennifer L. Frank, Katherine Bartholomew, Megan K. Farrell, Jamie Gentile, Omari Jones-Nelson, Kara Knight, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population. 5:20 THE EFFECTS OF ZETIA ON 3T3-L1 ADIPOCYTES Rosevear, John, Labonte, Eric, Hui, David (Dr. Engle) Zetia® (ezetimibe) is a plasma cholesterol reducing drug that inhibits dietary cholesterol absorption in the enterocytes of the gut. While the mechanism of action for ezetimibe remains controversial, it has been shown to be an effective inhibitor of cellular cholesterol uptake and may also interfere with cholesterol intracellular trafficking at higher concentrations. In order to ascertain the importance of cholesterol in adipogenesis, rat 3T3-L1 carcinoma preadipocytes were treated with ezetimibe. Ezetimibe treatment (40 μM) of 3T3-L1 cells accelerated lipid vacuole formation and altered gene expression consistent with adipocyte differentiation. At 100 μM, ezetimibe induced cell death. The proposed molecular target for ezetimibe, Niemann-Pick C1-like 1 (NPC1L1), has very little mRNA expression in 3T3-L1 cells (1000-fold less than intestine) and is unchanged by differentiation or drug treatment. This data suggests that sterol metabolism contributes to the regulation of adipogenesis and that ezetimibe may have other targets than NPC1L1.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Five: Tuesday, April 29, 2008 8:00 a.m. Section 05 lab Moderator: Mr. Nourian 8:00 Introduction 8:10 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Kara Knight, Katherine Bartholomew, Megan K. Farrell, Jennifer L. Frank, Jamie Gentile, Omari Jones-Nelson, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population.

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8:30 ANALYZING LEAF LITTER DECOMPOSITION RATES OF THE INVASIVE AMUR HONEYSUCKLE WITH NATIVE SPECIES IN SOUTHWESTERN OHIO FORESTS Maya Webb, Joseph Dagher, Manuel Alvarez (Dr. Brent Blair)

The Amur honeysuckle (Lonicera mackii), native to Asia, was introduced to Southwestern Ohio forests in the 1800s, and has become extremely invasive. This multi- stem shrub has begun to dominate the understory of many forests, preventing many native saplings to take root. Leaf litter decomposition rates of the honeysuckle were compared to native species of oak and maple. Litter was collected and air dried, then placed into 15cm x 15cm mesh bags, and placed on the forest floor to decompose. In all situations, the honeysuckle decomposed faster than each of the native species, even when placed on forest floors where honeysuckle was not present. The data support the hypothesis that the Amur honeysuckle leaf litter would have a faster decomposition rate than its native counterparts, affecting soil fertility to enhance its invasiveness in non-native communities. 8:50 CHANGES IN NFκB p50 SUBUNIT DISTRIBUTION ASSOCIATED WITH DIABETES PROVIDE A MECHANISM BEHIND THE DEVELOPMENT OF ALLODYNIA Bridget M. Larkin (Dr. Dorothy Engle) We investigated whether the ubiquitous transcription factor NFκB plays a role in the development of allodynia in diabetic rats. As NFκB is known to mediate inflammatory pain and diabetic retinopathy, altered NFκB activity in diabetic dorsal root ganglia (DRG) might lead to sensory neuropathy. We hypothesized that an upregulation of NFκB would be seen in the DRGs of diabetic animals that develop allodynia. The cellular distribution of p50 and p65, NFκB subunits, was investigated via immunohistochemistry in diabetic and control lumbar DRG. Neither subunit showed greater activation of the NFκB pathway in diabetic vs. control neurons. However, there were large, polarized clumps of p50 staining in the diabetic neurons’ cytoplasm that were not present in control neurons. From the present study, we conclude that there is clearly a difference in the neuronal distribution of p50 in DRGs between diabetic and control rats, but further investigation is necessary to determine what this means.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Six: Tuesday, April 29, 2008 10:30 a.m. Section 06 lab Moderator: Dr. Matre 10:30 Introduction 10:40 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Nilay J. Choksi, Jacqueline K. Baker, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.








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11:00 VARIATION IN WEIGHT AND LENGTH DISTRIBUTIONS OF EUROPEAN WALL LIZARDS IN TWO LOCATIONS IN CINCINNATI, OHIO Jason L. Go, Ashlee A. Dieckmann, Thomas P. McComas, Jason W. Westerbeck (Dr. George Farnsworth) The European Wall Lizard, Podarcis muralis, is an introduced species in Cincinnati. The species is well adapted to urban environments consisting of many cracks like unmortared stone walls. We compared populations in two locations: Eden Park and Torrence Parkway. Approximately 200 lizards were captured in 2007 and 2008. Lizards larger than 3 cm snout-to-vent were permanently tagged with subcutaneous RFID tags. For each of these lizards we also recorded date, time of capture, weather conditions, and weight. The weight data was assigned to five classes and a G-test was performed to determine whether or not the weights were independent of the two locations. A t-test was also performed on the averages of weight and length to compare populations. The populations were different between sites (P<0.05). Larger lizards were found in Eden Park compared to Torrence Parkway. This may be due to differences in the structure of the two habitats.

11:20 THE EFFECT OF ROYAL PEAT INOCULANT ON PHASEOLUS ACUTIFOLIUS, AND ITS ABILITY TO FIX NITROGEN Aaron M. Brooking, Tim M. Burns (Dr. Linda Finke)

Nitrogen fixation is a process required for the biological conversion of atmospheric nitrogen into usable forms. Nitrogen fixation can occur through a symbiotic relationship between a legume plant and its nitrogen fixing bacterial symbiont, or in associations between free-living diazotrophs and plant root systems. The tepary bean (Phaseolus acutifolius) is a drought-adapted legume from the southwestern U.S whose roots may be colonized by nodule-producing symbionts in its home range. The main objective of this experiment was to test for the effectiveness in nodule production of an inoculant that is used to inoculate other, more commonly grown species of beans, and to measure the amount of nitrogen fixation, if any occurs. Ten seeds of Phaseolus acutifolius were obtained and planted in individual pots with the addition of Royal Peat inoculum. Root systems were inspected for the presence of nodules, and nodulated systems were assayed for nitrogenase activity by the acetylene reduction method.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Seven: Tuesday, April 29, 2008 2:30 p.m. Section 07 lab Moderator: Mr. Nourian 2:30 Introduction 2:40 OPTIMIZING LENTIVIRAL PRODUCTION FOR THE VECTOR-MEDIATED GENE THERAPY TREATMENT OF MUCOPOLYSACCHARIDOSES I Jorden L. Arnett (Dr. Dorothy Engle) This study was conducted in order to determine the most effective way to generate high titer concentrated lentiviral vectors for use in in vivo gene therapy procedures. Proper transfection, harvest schedule, and concentration protocol can all greatly impact the titer of a lentiviral vector. A variety of harvest schedules and concentration protocols currently exist in an effort to obtain the highest titer lentiviral vectors possible. This study compared three harvest schedules using three different transfer vectors in each procedure. Two concentration protocols were also compared in order to determine which protocol generated the greatest percent change in titer after concentration. I was found that an alternating 12 and 21 hour harvest schedule yielded the least significant decrease in titer, compared to the first harvest titer, for each of the three vectors tested. The incorporation of a sucrose cushion resulted in a percent increase in titer of 5.34x103%, while the protocol omitting the sucrose cushion resulted in a percent increase in titer of 3.82x104%.

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3:00 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Omari Jones-Nelson, Katherine Bartholomew, Megan K. Farrell, Jennifer L. Frank, Jamie Gentile, Kara Knight, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population.

3:20 EVALUATING THE RELATIONSHIP BETWEEN H2O2-ASSOCIATED OXIDATIVE STRESS AND VON HIPPEL LINDAU (VHL) PROTEIN Ashley Roberts, Sarah Gillian, Danielle Maue (Dr. Waltke Paulding)

Many environmental factors, including hypoxia, can induce oxidative stress. Cells that are subjected to oxidative stress often generate reactive oxygen species (ROS), which include hydrogen peroxide (H2O2). Familial von Hippel-Lindau (VHL) disease develops in individuals that are born heterotrophic for the wild-type (wt)VHL gene, and who subsequently lose the remaining wt-VHL allele due to mutation. Excessive, unregulated quantities of ROS are known to damage cellular macromolecules, including proteins lipids and nucleic acids. We are currently examining the oxidative status of cells that express (wt-VHL) or lack (mut-VHL) the VHL protein, as a decrease in a cell’s ability to maintain “oxidative homeostasis” may be related to DNA damage, and expression of VHL pathology. Results from experiments in which H2O2 production was measured in VHL(+) or VHL(-) cell lines, under either normoxic (21% O2) or hypoxic (1% O2) conditions, revealed higher, basal amounts of H2O2 in VHL(-) cells in normoxic conditions, as contrasted to VHL(+) cells. Hypoxia reduced production of H2O2 in both VHL(+) and VHL(-) cell lines. Evaluation of expression levels of superoxide dismutase (SOD) and catalase, the 2 main enzymes involved in regulating H2O2 levels in the oxidative stress pathway, continue.

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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Eight: Tuesday, April 29, 2008 4:30 p.m. Section 08 lab Moderator: Dr. Jaskowiak 4:30 Introduction 4:40 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Quyen M. Nguyen, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.

4:40 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION








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Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) See Abstract Listed Above

5:10 VARIATION IN SEASONAL SWIM BEHAVIOR AMONG CAPTIVE FLORIDA MANATEES Anthony Kurian, Cody Dangelser, David N. Phillips (Dr. Charles Grossman) This study attempted to analyze the swim behavior of captive Florida manatees throughout the four seasons of the calendar year. In the wild, Florida manatees will swim more frequently during the summer months as food is plentiful and the water temperature is high. However, wild manatees’ swimming activity decreases greatly as the temperature declines in the winter months. The alternative habitat provided by the Cincinnati Zoo, with consistent environmental features, was expected to cause the captive manatees to deviate from their natural swimming behaviors. The manatees traversed an average of 12.3 blocks per run during the summer months of June, July, and August while navigating an average of 3.4 blocks per run during the winter months of December, January, and February. Though more data seems to be necessary, from the current results found, it can be concluded as of now, the captive manatees; swim behavior is similar to those in the wild.

5:30 A STUDY OF THE EFFECT OF DESICCATION ON NITROGEN FIXATION IN WHITE CLOVER Ryan M. Blandford (Dr. Linda Finke) This study was undertaken to determine whether desiccation (water deprivation) of white clover (Trifolium repens) would have an effect on the nitrogen fixing ability of its symbiotic bacteria (Rhizobium leguminosarum – Biovar trifolii, Sinorhizobium meliloti). It was hypothesized that desiccation would have the effect of reducing nitrogen fixation activity. Clover was planted in three separate pots at a rate of two hundred seeds per pot, and plants were regularly watered to enhance germination and early development. Once seedlings were well-established, the watering regimen was altered so that a different moisture level was produced in each pot, at levels of one, three, and five as determined on a Lincoln Irrigation hygrometer. After two weeks of this differential water treatment, randomly selected plants from each pot were carefully removed and their root systems were assayed for nitrogenase activity by the acetylene reduction assay.








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April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Nine: Wednesday, April 30, 2008 8:30 a.m. Section 01 lab Moderator: Mr. Nourian 8:30 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Amanda N. Snyder, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.

8:50 AZOSPIRILLUM BRASILENSE NITROGEN FIXATION IN AUXIN INDUCED PARA-NODULES OF ORYZA SATIVA L. (WETLAND RICE) UNDER








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HYDROPONIC CONDITIONS Adam M. McHenry (Dr. Linda Finke)

A unique symbiotic relationship between Azospirillum brasilense nitrogen-fixing bacteria and the roots of wetland rice was studied in this experiment. Because this symbiosis does not occur naturally with grasses, the plant growth hormone auxin was utilized to mediate this relationship by enhancing the growth of root para-nodules, similar to those seen in legume roots. Seedlings in the experimental group were both treated with auxin and inoculated with bacteria, while three control groups were treated with bacteria, auxin, or neither. A simple hydroponic system enabled the precise control of nutrient levels as the seedlings were cultivated at 30ºC (±2 ºC) under natural light conditions. Initial and final plant mass was recorded and acetylene reduction assays were conducted at the close of the experiment. The acetylene reduction assay quantifies nitrogen fixation, and it was used to test both the potentially symbiotic root systems of experimental groups as well as the bacteria alone.

9:10 VOCALIZATION DIFFERENCES BETWEEN MALE AND FEMALE CAPTIVE FLORIDA MANATEES Melissa M. O’Brien, Gina Mittenzwei, Mary C. Ansbro (Dr. Charles J. Grossman, Ph.D.) Vocalizations of captive Florida manatees (Trichechus manatus latirostris) were studied to determine if there are any differences in the rate of vocalization frequency or length of squeaks between males and females. Given that the females must communicate with their young in the wild, we hypothesize that female manatees will vocalize at an increased rate compared to males, and that the length of squeaks will differ between the sexes. Two male manatees housed at the Cincinnati Zoo and two female manatees housed at the Columbus Zoo were studied over the course of eight months. Preliminary statistical analysis of the data collected suggested that female squeaks are significantly longer (p= 1.385x10-7) than male squeaks with a mean time of 0.308 seconds for the females and a mean time of 0.275 seconds for the males. The data has also shown a highly significant difference (p=6.816x10-6) between the rate of male and female manatee vocalizations with a mean time between female squeaks of 62.92 seconds and a mean time of 113.3 seconds between male squeaks. From these preliminary studies, the results also suggest that vocalizations taking place are complex enough to be used for communication between animals. Additional data is currently being analyzed in order to further explore differences in manatee vocalization. 9:10 VOCALIZATION DIFFERENCES BETWEEN MALE AND FEMALE CAPTIVE FLORIDA MANATEES Gina Mittenzwei, Melissa M. O’Brien, Mary C. Ansbro (Dr. Charles J. Grossman, Ph.D.) See above listed abstract.

19



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Ten: Wednesday, April 30, 2008 10:30 a.m. Section 02 lab Moderator: Ms. Tehrani 10:30 VARIATION IN WEIGHT AND LENGTH DISTRIBUTIONS OF EUROPEAN WALL LIZARDS IN TWO LOCATIONS IN CINCINNATI, OHIO Jason W. Westerbeck, Ashlee A. Dieckmann, Jason L. Go, Thomas P. McComas, (Dr. George Farnsworth) The European Wall Lizard, Podarcis muralis, is an introduced species in Cincinnati. The species is well adapted to urban environments consisting of many cracks like unmortared stone walls. We compared populations in two locations: Eden Park and Torrence Parkway. Approximately 200 lizards were captured in 2007 and 2008. Lizards larger than 3 cm snout-to-vent were permanently tagged with subcutaneous RFID tags. For each of these lizards we also recorded date, time of capture, weather conditions, and weight. The weight data was assigned to five classes and a G-test was performed to determine whether or not the weights were independent of the two locations. A t-test was also performed on the averages of weight and length to compare populations. The populations were different between sites (P<0.05). Larger lizards were found in Eden Park compared to Torrence Parkway. This may be due to differences in the structure of the two habitats.

20

10:50 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Jamie Gentile, Katherine Bartholomew, Megan K. Farrell, Jennifer L. Frank, Omari Jones-Nelson, Kara Knight, Zak Woods (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population.

11:10 THE IMPACT OF THE INVASIVE SPECIES LONICERA MAACKII ON SOIL NUTRIENT LEVELS Touraj Karkevandian, Shannon M. Chambers, Joseph R. Lally (Dr. Brent Blair) The invasive species Lonicer Maackii (Amur Honeysuckle) is thought to have a competitive advantage over native species in Southern Ohio which accounts for its high distribution. We believe that Honeysuckle alters soil nutrient content and thereby has a competitive advantage over native species. Our group collected soil samples from Honeysuckle infested areas and natural areas in Cincinnati forests to observe potential differences in pH, nitrate and ammonia levels. Honeysuckle demonstrated more acidic soils compared to native soils while the nitrogen tests were inconclusive and need further study. The understanding of how Honeysuckle alters its environment for its own success is important in controlling future invasions of Honeysuckle and other invasive species.

21



April 28, 29, 30, May 1, 2008

Albers Hall - 307 Session Eleven: Wednesday, April 30, 2008 2:30 p.m. Section 03 lab Moderator: Dr. Matre 2:30 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Katherine L. von Brecht, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder (Dr. Close-Jacob)

L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.








22

2:30 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Nicholas A. Jabre, Katherine L. von Brecht, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Jaclyn M. Stenger, Amanda N. Snyder (Dr. Close-Jacob) See abstract listed above. 3:00 NON-INVASIVE MEASUREMENT OF FECAL CORTICOSTERONE TO ASSESS STRESS Alexis Wickersham, Paul Blair, Jon Salman, Tomilyn Thornberry (Dr. Waltke Paulding) Corticosterone is a hormone produced by the adrenal gland that is commonly measured as an indicator of physiological stress. Accurate quantification of corticosterone levels typically requires measuring the hormone in blood plasma and may also require the use of radioisotopes. Because obtaining blood samples from animals is a complicated, stressful process, which likely increases corticosterone production, and use of radioisotopes is hazardous, expensive, and requires special training and authorization, the goal of our project is to develop a non-invasive, non-radioactive method to quantify corticosterone. Fecal samples were obtained from several birds and mice and conditions for measurement of corticosterone using an immunometric assay are being standardized. Once developed, this test will be utilized to quantify the effect of various environmental stressors in mocking birds.








23



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Twelve: Wednesday, April 30, 2008 4:30 p.m. Section 04 lab Moderator: Mr. Pecquet 4:30 THE EFFECT OF ROYAL PEAT INOCULANT ON PHASEOLUS ACUTIFOLIUS, AND ITS ABILITY TO FIX NITROGEN Tim M. Burns, Aaron M. Brooking, (Dr. Linda Finke)

Nitrogen fixation is a process required for the biological conversion of atmospheric nitrogen into usable forms. Nitrogen fixation can occur through a symbiotic relationship between a legume plant and its nitrogen fixing bacterial symbiont, or in associations between free-living diazotrophs and plant root systems. The tepary bean (Phaseolus acutifolius) is a drought-adapted legume from the southwestern U.S whose roots may be colonized by nodule-producing symbionts in its home range. The main objective of this experiment was to test for the effectiveness in nodule production of an inoculant that is used to inoculate other, more commonly grown species of beans, and to measure the amount of nitrogen fixation, if any occurs. Ten seeds of Phaseolus acutifolius were obtained and planted in individual pots with the addition of Royal Peat inoculum. Root systems were inspected for the presence of nodules, and nodulated systems were assayed for nitrogenase activity by the acetylene reduction method.

24

4:50 VARIATION IN WEIGHT AND LENGTH DISTRIBUTIONS OF EUROPEAN WALL LIZARDS IN TWO LOCATIONS IN CINCINNATI, OHIO Ashlee A. Dieckmann, Jason L. Go, Thomas P. McComas, Jason W. Westerbeck (Dr. George Farnsworth) The European Wall Lizard, Podarcis muralis, is an introduced species in Cincinnati. The species is well adapted to urban environments consisting of many cracks like unmortared stone walls. We compared populations in two locations: Eden Park and Torrence Parkway. Approximately 200 lizards were captured in 2007 and 2008. Lizards larger than 3 cm snout-to-vent were permanently tagged with subcutaneous RFID tags. For each of these lizards we also recorded date, time of capture, weather conditions, and weight. The weight data was assigned to five classes and a G-test was performed to determine whether or not the weights were independent of the two locations. A t-test was also performed on the averages of weight and length to compare populations. The populations were different between sites (P<0.05). Larger lizards were found in Eden Park compared to Torrence Parkway. This may be due to differences in the structure of the two habitats.

5:10 THE IMPACT OF THE INVASIVE SPECIES LONICERA MAACKII ON SOIL NUTRIENT LEVELS Shannon M. Chambers, Touraj Karkevandian, Joseph R. Lally (Dr. Brent Blair) The invasive species Lonicer Maackii (Amur Honeysuckle) is thought to have a competitive advantage over native species in Southern Ohio which accounts for its high distribution. We believe that Honeysuckle alters soil nutrient content and thereby has a competitive advantage over native species. Our group collected soil samples from Honeysuckle infested areas and natural areas in Cincinnati forests to observe potential differences in pH, nitrate and ammonia levels. Honeysuckle demonstrated more acidic soils compared to native soils while the nitrogen tests were inconclusive and need further study. The understanding of how Honeysuckle alters its environment for its own success is important in controlling future invasions of Honeysuckle and other invasive species.

25



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Thirteen: Thursday, May 1, 2008 8:00 a.m. Section 05 lab Moderator: Mr. Nourian 8:00 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Anthony J. Parr, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Jaclyn M. Stenger, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.








26

8:20 QUANTIFYING FUNGAL VIABILITY IN AIR AND WATER SAMPLES USING QUANTITATIVE PCR AFTER TREATMENT WITH PROPIDIUM MONOAZIDE (PMA) Chris Hartmann (Stephen Vesper, U.S. EPA) This study focused on developing a new method that would differentiate between viable and non-viable fungal cells. The fungal cells used in the study were Aspergillus fumigatus, A. flavus, A. terreus, Mucor racemosus, Rhizopus stolonifer and Paecilomyces variotti. These fungal species were chosen because they represent some of the most harmful and infectious fungi in the United States. To determine fungal viability propidium monoazide (PMA) was used to stain dead cells. PMA was able to enter the cell membrane of dead cells and intercalate the DNA. After a quick incubation time samples were exposed to intense blue LEDs which inactivated remaining PMA. Mold samples were then quantified using mold specific quantitative polymerase chain reaction (MSQPCR). It was found that dead and live fungal cells showed a 100 to 1,000-fold difference in cell viability. These results were consistent with the findings of traditional culturing methods.

8:40 NON-INVASIVE MEASUREMENT OF FECAL CORTICOSTERONE TO ASSESS STRESS Tomilyn Thornberry, Paul Blair, Jon Salman, and Alexis Wickersham (Dr. Waltke Paulding) Corticosterone is a hormone produced by the adrenal gland that is commonly measured as an indicator of physiological stress. Accurate quantification of corticosterone levels typically requires measuring the hormone in blood plasma and may also require the use of radioisotopes. Because obtaining blood samples from animals is a complicated, stressful process, which likely increases corticosterone production, and use of radioisotopes is hazardous, expensive, and requires special training and authorization, the goal of our project is to develop a non-invasive, non-radioactive method to quantify corticosterone. Fecal samples were obtained from several birds and mice and conditions for measurement of corticosterone using an immunometric assay are being standardized. Once developed, this test will be utilized to quantify the effect of various environmental stressors in mocking birds.

27



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Fourteen: Thursday, May 1, 2008 10:30 a.m. Section 06 lab Moderator: Dr. Matre 10:30 VOCALIZATION DIFFERENCES BETWEEN MALE AND FEMALE CAPTIVE FLORIDA MANATEES Mary C. Ansbro, Melissa M. O’Brien, Gina Mittenzwei (Dr. Charles J. Grossman, Ph.D.) Vocalizations of captive Florida manatees (Trichechus manatus latirostris) were studied to determine if there are any differences in the rate of vocalization frequency or length of squeaks between males and females. Given that the females must communicate with their young in the wild, we hypothesize that female manatees will vocalize at an increased rate compared to males, and that the length of squeaks will differ between the sexes. Two male manatees housed at the Cincinnati Zoo and two female manatees housed at the Columbus Zoo were studied over the course of eight months. Preliminary statistical analysis of the data collected suggested that female squeaks are significantly longer (p= 1.385x10-7) than male squeaks with a mean time of 0.308 seconds for the females and a mean time of 0.275 seconds for the males. The data has also shown a highly significant difference (p=6.816x10-6) between the rate of male and female manatee vocalizations with a mean time between female squeaks of 62.92 seconds and a mean time of 113.3 seconds between male squeaks. From these preliminary studies, the results also suggest that vocalizations taking place are complex enough to be used for communication between animals. Additional data is currently being analyzed in order to further explore differences in manatee vocalization.

28

10:50 ANALYZING LEAF LITTER DECOMPOSITION RATES OF THE INVASIVE AMUR HONEYSUCKLE WITH NATIVE SPECIES IN SOUTHWESTERN OHIO FORESTS Joseph Dagher, Maya Webb, Manuel Alvarez (Dr. Brent Blair)

The Amur honeysuckle (Lonicera mackii), native to Asia, was introduced to Southwestern Ohio forests in the 1800s, and has become extremely invasive. This multi- stem shrub has begun to dominate the understory of many forests, preventing many native saplings to take root. Leaf litter decomposition rates of the honeysuckle were compared to native species of oak and maple. Litter was collected and air dried, then placed into 15cm x 15cm mesh bags, and placed on the forest floor to decompose. In all situations, the honeysuckle decomposed faster than each of the native species, even when placed on forest floors where honeysuckle was not present. The data support the hypothesis that the Amur honeysuckle leaf litter would have a faster decomposition rate than its native counterparts, affecting soil fertility to enhance its invasiveness in non- native communities. 11:10 NON-INVASIVE MEASUREMENT OF FECAL CORTICOSTERONE TO ASSESS STRESS Jon Salman, Paul Blair, Tomilyn Thornberry, and Alexis Wickersham (Dr. Waltke Paulding) Corticosterone is a hormone produced by the adrenal gland that is commonly measured as an indicator of physiological stress. Accurate quantification of corticosterone levels typically requires measuring the hormone in blood plasma and may also require the use of radioisotopes. Because obtaining blood samples from animals is a complicated, stressful process, which likely increases corticosterone production, and use of radioisotopes is hazardous, expensive, and requires special training and authorization, the goal of our project is to develop a non-invasive, non-radioactive method to quantify corticosterone. Fecal samples were obtained from several birds and mice and conditions for measurement of corticosterone using an immunometric assay are being standardized. Once developed, this test will be utilized to quantify the effect of various environmental stressors in mocking birds.

29



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Fifteen: Thursday, May 1, 2008 2:30 p.m. Section 07 lab Moderator: Mr. Nourian 2:30 ROLE OF L- AND T-TYPE CA2+ CHANNELS IN BOVINE CORONARY ARTERY CONTRACTION Jaclyn M. Stenger, Jacqueline K. Baker, Nilay J. Choksi, Charles A. Gabis, Nicholas A. Jabre, Quyen M. Nguyen, Emmanuel A. Ofori, Anthony J. Parr, Amanda N. Snyder, Katherine L. von Brecht (Dr. Close-Jacob) L-type and T-type Ca2+-channels mediate contractions in smooth muscle. Studies have shown that hypoxia inhibits L-type Ca+2-channels, causing relaxation. We investigated the role of these channels in force maintenance under normoxic and hypoxic conditions. We also explored the role of L-type Ca2+-channels in oscillatory behavior during sustained contraction. Bovine LAD coronary arteries were isolated and contracted with 5x10-8M U46619. Tissues were then separately subjected to either hypoxic conditions or treated with nifedipine or mibefradil, L-type and T-type inhibitors, respectively. Hypoxic conditions showed an average 17% relaxation in arterial force. L-type inhibitors showed an average 35% relaxation, and T-type inhibitors showed an average 6% relaxation. In the event of oscillating contractions, NiCl2 or hypoxia were used to investigate the involvement of L-type Ca2+-channels. Hypoxic conditions eliminated oscillations completely, while NiCl2 caused no change. While hypoxia and nifedipine results support a role for L-type channels in sustained force in bovine coronary artery contractions, mibefradil results indicate a possible role for T-type channels in force maintenance as well.








30

2:50 EXAMINATION OF THE SEX RATIO OF THE NORTHERN MOCKINGBIRD BY CHD GENE INTRON REGION AMPLIFICATION Matthew C. Broderick, Dan J. Schoeff, Brett E. Schrand, Christopher C. Stobart (Drs. Dorothy Engle and George Farnsworth) The sex ratio of offspring in some species may be different from 1:1. This may arise if male and female offspring offer different reproductive value. In birds, females are heterogametic (ZW) and males are homogametic (ZZ). A molecular sexing technique has been developed which amplifies an intron region homologous to both chromosomes and can be a diagnostic tool for avian sexing (Griffiths et al. 1998). We successfully adapted this technique to the molecular sexing of a Northern Mockingbirds (Mimus polyglottos). We collected feathers from 70 Northern Mockingbird nestlings sampled over three breeding seasons. We used PCR and agarose gel electrophoresis to visualize the DNA amplified by primers P2 and P8. In all, 42 chicks were males and 28 chicks were females, not a significant bias in nestling sex ratio (P > 0.05). Future studies may use this technique as a means of investigating the sex ratio of other avian species. 3:10 MEASURING NITROGEN-FIXING ABILITIES OF A RELATIONSHIP BETWEEN WINTER WHEAT (TRITICUM AESTIVUM) AND THE BACTERIUM AZOSPIRILLUM BRASILENSE

Maricor K. Docena, Katie M. Zak (Dr. Linda Finke)

The nitrogen fixing bacteria Azospirillum brasilense can colonize wheat plant roots and provide the plant with essential nitrogen in the form of ammonia. While symbiotic nitrogen fixing relationships are well understood, this experiment explores looser associations such as the one between A. brasilense and winter wheat, which seems to be beneficial to plant growth. Plants were grown hydroponically and the experimental group was inoculated with A. brasilense in the absence of nitrogen in the plant medium. Plants given a complete nitrogen-containing medium and those given a nitrogen-free medium without bacteria served as controls. Plant growth was recorded photographically and by final dry weight. Acetylene reduction assay of plant roots was performed to measure nitrogenase activity, the enzyme responsible for the nitrogen fixing abilities of such bacteria. Preliminary photographic results indicated that positive control plants with nitrogen-containing medium had the best growth while the experimental and second control group appeared the same.

31



April 28, 29, 30, May 1, 2008

Albers Hall - 307

Session Sixteen: Thursday, May 1, 2008 4:30 p.m. Section 06 lab Moderator: Dr. Jaskowiak 4:30 CRANIODENTAL MORPHOLOGY IN SKUNKS AND MONGOOSES Luke J. Rothan (Dr. William Anyonge) This study was undertaken in order to investigate the generation of bite forces in the skulls of the common mongoose (Herpestes edwardsi), the striped skunk (Mephitis mephitis), the western spotted skunk (Spilogale gracilis), and the meerkat (Suricata suricata) in relation to their dietary preferences. All of these species share an omnivorous diet, feeding heavily on insects, spiders, small mammals, lizards, birds, eggs, nuts, and berries. In addition, H. edwardsi and S. suricata are well known for their swift speed and skill in killing poisonous snakes with a single bite to the neck without being hurt. Based on these predatory habits of H. edwardsi and the S. suricata, it was hypothesized that these species would exhibit a larger bite force at the front of their jaws (where greater force is needed to swiftly kill prey), namely at the first canines, than M. mephitis and S. gracilis. Four cranial and 7 mandibular measurements were made on each skull and then used to compute several indices that estimated the size of jaw- closing muscles (masseter and the temporalis) and their relative moment-arms. An analysis of variance (ANOVA) was performed on the transformed indices and tested for significant differences. The results did not support the hypothesis. S. gracilis and M. mephitis exhibited greater mechanical advantage (larger bite forces) at both the first lower molars and lower canines in comparison to H. edwardsi and S. suricata. H. gracilis and M. mephitis displayed also larger temporalis muscles and shorter jaw lengths. It can be inferred that the latter species have evolved skull morphologies that are adapted to generating large bite forces.

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4:50 EVALUATING THE RELATIONSHIP BETWEEN H2O2-ASSOCIATED OXIDATIVE STRESS AND VON HIPPEL LINDAU (VHL) PROTEIN Sarah Gillian, Danielle Maue, and Ashley Roberts (Dr. Waltke Paulding)

Many environmental factors, including hypoxia, can induce oxidative stress. Cells that are subjected to oxidative stress often generate reactive oxygen species (ROS), which include hydrogen peroxide (H2O2). Familial von Hippel-Lindau (VHL) disease develops in individuals that are born heterotrophic for the wild-type (wt)VHL gene, and who subsequently lose the remaining wt-VHL allele due to mutation. Excessive, unregulated quantities of ROS are known to damage cellular macromolecules, including proteins lipids and nucleic acids. We are currently examining the oxidative status of cells that express (wt-VHL) or lack (mut-VHL) the VHL protein, as a decrease in a cell’s ability to maintain “oxidative homeostasis” may be related to DNA damage, and expression of VHL pathology. Results from experiments in which H2O2 production was measured in VHL(+) or VHL(-) cell lines, under either normoxic (21% O2) or hypoxic (1% O2) conditions, revealed higher, basal amounts of H2O2 in VHL(-) cells in normoxic conditions, as contrasted to VHL(+) cells. Hypoxia reduced production of H2O2 in both VHL(+) and VHL(-) cell lines. Evaluation of expression levels of superoxide dismutase (SOD) and catalase, the 2 main enzymes involved in regulating H2O2 levels in the oxidative stress pathway, continue. 5:10 GENETIC ANALYSIS OF CINCINNATI AREA PODARCIS MURALIS POPULATION AS A INDICATOR OF ACCURACY IN BOTTLENECK POPULATION TESTS Zak Woods, Katherine Bartholomew, Megan K. Farrell, Jennifer L. Frank, Jamie Gentile, Omari Jones-Nelson, Kara Knight, (Dr. Dorothy Engle) A small population of Podarcis muralis lizards were brought to the greater Cincinnati area from Milan, Italy in the 1950’s. The lizards have adapted to the area and continue to successfully propagate. The Lizard population is known to have experienced a bottleneck. Therefore by using this population as a control, several mathematical equations can be analysed, to see if the equations can predetermine if a given population has experienced a bottleneck. This experiment is intended to use the genetic variability found in the local wall lizard population to determine the validity of such a test. After extracting DNA from the tails of the experimental organisms, three different microsatellite loci were analysed for levels of heterozygosity and observed using capillary electrophoresis. The results of the capillary electrophoresis will be entered into the test, and the results should validate the equations being tested for the presence of a bottleneck population.

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