Biological Sciences poster abstracts.
Antibiotic resistance is becoming more prevalent due to the common usages of antibiotics. Pharmaceutical companies are continuously developing new drugs to compensate for this resistance. Therapy regimes are becoming more complicated for physicians to try to combat infections. Bacteria are becoming more and more effective in surviving these treatments via their many mechanisms of DNA transfer and uptake. In wastewater treatment plants, these mechanisms are put to their most efficient use and may include transformation, transduction, and conjugation. Surveillance of resistance patterns has shown that wastewater treatments facilities are an opportune location for the transmission of antibiotic resistance. This project investigated the resistance of isolates from aerobic digest collected from the Five Mile Creek Wastewater Treatment facility in Birmingham, AL. Seventeen isolates were tested for their susceptibility to thirteen antibiotics. Influent to the aerobic digester and effluent from the aerobic digester was also tested for resistance.
Characterizing the role of NF-kappaB in gliomagenesis.Jordan A. Beard, Department of Biological and Environmental Sciences, Samford University, Birmingham, AL 35229. Susan Nozell and Etty N. Benveniste, University of Alabama at Birmingham, Birmingham, AL 35294.
Gliomas are the most common primary tumors of the central nervous system. The World Health Organization categorizes gliomas into four different grades, ranging from least to most aggressive. Because of their diffusely infiltrative nature, gliomas are difficult to detect, resect or treat. As such, patients diagnosed with grade IV gliomas or Glioblastoma, have the worst prognosis with a survival time of less than 12 months. The NF-kB transcription factor is an important mediator of inflammation and immune responses and consists of two subunits, p65 and p50. Although NF-kB is tightly regulated, during an immune or inflammatory response, NF-kB can induce the expression of many genes that regulate the processes of angiogenesis, cell growth, invasion and apoptosis. As such, in cancers, if NF-kB is inappropriately activated, it may contribute to the formation and/or progression of tumors. However, at present, the exact nature of NF-kB in gliomas is unclear and remains to be addressed. Herein, we propose to investigate the role of p65 in gliomagenic behavior. We hypothesize that through NF-kB, gliomas are empowered to grow, invade and evade apoptotic stimuli. To test this, we will use a glioma cell that inducibly regulates NF-kB activity by controlling endogenous p65 levels to analyze the effects of NF-kB on cell growth, invasion and apoptotic resistance.
Chemical defenses against diatom fouling in Antarctic macroalgae: insights from bioassay guided fractionation. Hamel P. Sevakl, Margaret O. Amsler', J. Alan Maschel (2)Charles D. Amslerl, James B. McCMntoekl, and Bill J. Baker2 IDept. of Biology, Univ. of Ala at Birmingham, Birmingham, AL 35294, USA 2Dept. of Chemistry, University of South Florida, Tampa, FL 33620.
The prevention of fouling in marine algae involves complex processes that are not yet completely understood. Some antifoulant activity may be attributable to single compounds, whereas others may require synergetic interactions between collections of compounds. Antarctic marine benthic systems are a particularly relevant habitat for studying diatom antifoulants because benthic diatoms are seasonally extraordinarily abundant. In a previous study, we investigated crude organic extracts of a broad suite of macroalgae from the western Antarctic Peninsula for toxicity against sympatric diatoms. In the present study, we bioassayed specific HPLC-generated fractions of crude extracts from four common macroalgae found in the western Antarctic Peninsula (Georgiella confluens, Desmarestia antarctica, Trematocarpus antarcticus, Gigartina skottsbergii). All species had shown significant activity against diatoms as crude organic extracts but not in feeding bioassays with sympatric herbivores. Diatom viability was measured with live/dead staining (fluorescein diacetate and Evans blue). Diatoms were exposed to macroalgal extracts at several concentrations (1x, 3x or 10x their calculated natural concentration on a volumetric basis). Bioactivity was not detected at even 10 x in any of the isolated fractions from the macroalgae. However, in all species except Trematocarpus antarcticus, a combination of all the isolated fractions at a 10 x concentration resulted in potent bioactivity with 99% diatom mortality. These findings indicate that in all species, individual compounds are inactive in diatom antifoulant assays. Rather, some as yet unknown combination of individual compounds results in an additive or synergistical biochemical effect that is toxic to diatoms.
EFFECTS OF HERBAL EXTRACTS ON BACTERIA AND HUMAN ADENOCARCINOMA CELLS. Florence Okafor, Tatiana Kuklitarev, Jennifer Jones, Leonard Williams & Mostafa Dokhanian. Alabama A&M University, Normal AL 35762.
Cancer is life a threatening disease that affects individuals of all ages. The well-known herb, Aloe vera, may alter the grim perception that accompanies cancer. Aloe vera is said to be effective against some forms of cancer. The purpose of our experiment is to determine if these assertions are correct. CaC02 cancer cells and Bacteria were exposed to Aloe vera, Garcinia kola and fennel extracts. Escherichia coli and Bacillus thuringiensis were exposed to Aloe vera and Garcinia kola as a pilot study. The bacteria species were grown in Brain Heart Infusion for 48hr to get exponential growth. The microorganisms were then exposed to the herbal extracts and allowed contact times of 30 minutes to one hour at ambient temperature including control plates. Aloe vera inhibited the growth both microorganisms. Garcinia kola had no effect on the growth of the experimental microorganisms. Human adenocarcinoma (CaCO2) cancer cells were grown in Hanks Balance Saline Solution (HBSS). Several plates were prepared including, a low control, a high control, and all were exposed to the experimental herbal extracts. Aloe vera and Garcinia kola caused apoptosis in the CaCO2 cells. Fennel had little or no effects on the CaCO2 cells, indicating that fennel does not cause apoptosis. This preliminary investigation confirmed that Aloe vera leads to programmed cell death in human adenocarcinoma cells.
EPIBRASSINOLIDE (EB) EFFECTS ON THE DEVELOPMENT OF JAPANESE MEDAKA FISH (ORYZIAS LAPTIPES) EGGS. James P. Weaver, B.S., Ryan A. Fogg, B.S., Ronald N. Hunsinger, Ph.D., W. Mike Howell, Ph.D. and Ronald L. Jenkins, Ph.D. (Deceased-Spring 2007), Department of Biological and Environmental Sciences, Samford University, Birmingham, AL 35229.
Epibrassinolide (EB) is a recently discovered type of plant steroid. Studies show that hormones like EB impact cell division, cell elongation, and root growth in plants. However, no research to date has been published concerning the effects of EB on animal cells. The purpose of this experiment was to monitor the effects of different levels of EB on developing Japanese Medaka fish embryos. Our results indicated that EB, with respect to controls, caused: 1) an earlier emergence of a heartbeat, 2) an accelerated heart rate, 3) an acceleration of egg hatching, 4) an acceleration of ocular development and 5) an acceleration of vascular development.
GLYCOSYLATION OF HUMAN IGA1: A MASS SPECTROMETRIC APPROACH AND ITS IMPLICATIONS FOR THE DISEASE IGA NEPHROPATHY. Stephanie Wall, Dept. of Chemistry, Univ. of Ala. at Birmingham. Stacy Hall, Bruce Julian, and Jan Novak, Dept. of Microbiology, Univ. of Ala. at Birmingham. Michelle Gomes and Andrew Herr, Dept. Molecular Genetics, Biochemistry & Microbiology, Univ. Cincinnati College of Medicine. Matthew Renfrow, Biochemistry and Molecular Genetics Department, University of Alabama at Birmingham. Birmingham, AL 35294.
IgA Nephropathy (IgAN) is a disease in which circulating immune complexes (CICs) with high amounts of Immunoglobulin A (IgA) become deposited in the kidney. IgA, of the isoform IgA 1, is normally glycosylated by up to six O-glycans and two N-glycans. The O-glycans are attached to serine and threonine residues within the hinge region, located between the first and second constant domains on the heavy chain of IgA. One of the two N-glycans is found attached within the second constant domain of the heavy chain. The other N-glycan is found attached to a tailpiece segment after the third constant domain of the heavy chain of IgA. The disease pathology of IgAN is thought to be due to abnormal glycosylation of IgA1. High resolution mass spectrometry was used to identify the various glycoforms IgAl within a single serum sample. The focus of this project is to develop analytical techniques to identify differences within the IgAl glycosylation patterns of IgAl from IgAN patients and IgAl from normal healthy controls.
Greenfly Orchid (Epidendrum magnoliae Muhl., Orchidaceae) in Alabama. Alvin Diamond, Department of Biological and Environmental Sciences, Troy University, Troy, AL 36082.
Epidendrum magnoliae is the most northerly distributed epiphytic orchid in the Western Hemisphere, occurring from North Carolina south and west to Louisiana and in north eastern Mexico. It is the only epiphytic orchid native to Alabama. The herbaria of Auburn University (AUA), the University of Alabama (UNA), the University of South Alabama (USAM), the University of West Alabama, Jacksonville State University (JSU), the Anniston Museum of Natural History, and Troy University (TROY) were searched for collection records of this species. This historical data along with field observations were used to determine the distribution of the species within Alabama, the specie's preferred habitat, host tree specificity, and dates of flowering and fruiting.
HERPETOLOGY AT JACKSONVILLE STATE UNIVERSITY. George Cline, James Rayburn, and Chris Murdock. Biology Dept., Jacksonville State University, Jacksonville, AL 36265-1602.
Herpetology research in Alabama has historically been driven by research at larger, Ph.D. granting institutions. Three faculty at Jacksonville State University now represent a core of researchers with complementary research methods that have herpetology interests. Dr. George Cline is a field herpetologist whose research topics include frog communication, herpetological community structure, herptile conservation biology, and amphibian and reptile ommunities. He is particularly interested in temporal and acoustical partitioning in frog communities. Dr. James Rayburn is an ecotoxicologist who's research interests lie in amphibian development and amphibian metamorphisis. He uses Frog Embryo Teratogenesis Assay- Xenopus (FETAX) as one of his research techniques to study the effects of chemicals and other environmental factors on amphibians, and biomarkers to study vitellogenin induction by anthropogenic estrogens. Research topics currently being addressed in Dr. Chris Murdock's laboratory include regulatory mechanisms within the hypothalamus-pituitary-gonad axis of snakes, along with possible temperature effects on sex determination in amphibians. In these studies herpetology is addressed from a molecular biology/biotechnology perspective in order to address the underlying physiological and development cascades in the reproductive axis of these organisms. Specific techniques currently being utilized include-. PCR, gene cloning, quantitative real-time PCR, and gene sequencing. The complementary approach to herp research at JSU represents a synergistic collaboration among individuals with diverse skills. This unique combination of faculty and skills offers exciting new ways to approach herpetological research
In Vitro Three Body Wear of 5 Composite Resins. AYESHA SWARN, D. CAKIR, L.C. RAMP, D. DEAN and J.O. BURGESS. Department of Material Science and Engineering, Department of Prosthodontics. University of Alabama at Birmingham, Birmingham, AL 35294.
Composite resins are being increasingly used as posterior restorative materials and their long term success depends upon their ability to resist wear under masticatory loads. Objective: To compare the in-vitro wear of 5 commercially available composite resins. Materials and Methods: Six mm thick flat composite specimens (n = 8) were prepared and polymerized with a curing light (560mW/cm2 Ivoclar VIVADENT Inc.) in 2mm intervals following the manufacturer's instructions. Specimens were stored at 37[degrees]C, for 24 hours. After storage, specimens were mounted in brass holders and loaded into an Alabama Wear Testing Device for 400,000 cycles at 1.2Hz applying a 75N force. The test was performed with a stainless steel antagonist. A slurry of 50um PMMA beads (15g PMMA/9g water) was used as a third body medium. The volumetric loss through wear of the specimens was determined using a 3D non-contact profilometer (Proscan 2000, Scantron Industrial Products Ltd. Taunton, England). A one-way ANOVA and Tukey's post-hoc test were used for data analysis. Results:The materials and corresponding wear volume in cubic mm were: EsthetX (0.067[+ or -]0.024); Filtek Supremeplus 0.045[+ or -]0.02); Miris2(0.076[+ or -]0.029); Premise(0.035[+ or -]0.008);Venus (0.049[+ or -]0.019) There are significant differences in between the in-vitro localized wear volume of Miris2 and Premise only. Conclusions: All materials tested showed wear in varying degrees. The materials with higher wear resistance are more favorable for posterior restorations. Supported in part by a grant from Coltene Whaledent.
INCUBATION TEMPERATURE EVALUATION FOR TURTLES WITH TEMPERATURE-DEPENDENT SEX DETERMINATION. Corie L. Therrien and Thane Wibbels, Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294.
A variety of reptiles, including all sea turtles, have temperature-dependent sex determination (TSD), where incubation temperature determines gender. This form of sex determination has significants conservational implications since it has the potential of producing highly biased sex ratios which can affect the reproductive output of a population. TSD is of particular interest to conservation programs that use hatcheries to artificially incubate eggs. Such programs need to select specific incubation temperatures in an effort to produce a desired sex ratio. The purpose of this study was to evaluate optimal temperatures for incubating eggs in hatchery programs. For example, if a 1:1 sex ratio is desired, is it better to incubate all the eggs at the pivotal temperature (where half the hatchlings will be male and half female) or is it better to incubate half the eggs at an all male-producing temperature and half at an all female-producing temperature? To address this question, the red eared slider turtle was used as a model since its TSD is similar to that of sea turtles. The reproductive tracts were compared between late-stage embryos incubated at temperatures that produced either all females, mostly females, mostly males, or all males. The gross morphology and histology of the reproductive tracts of these four groups were compared. The results indicate significant variation between the groups. This suggests that certain incubation temperatures may be optimal for producing the most reproductively-fit individuals.
ISOLATION AND CHARACTERIZATION OF SCARECROW SUPPRESSOR MUTANTS IN ARABIDOPSIS THALIANA. Vijaya K. Mekala and Joanna Wysocka-Diller, Dept. of Biological Sciences, College of Science and Mathematics, Auburn University, Auburn, AL-36849.
SCARECROW (SCR) is a transcriptional regulator that plays key roles in several developmental processes in a model plant Arabidopsis thaliana. SCR orthologs have been identified in agriculturally important plants such as rice and corn. It has also been demonstrated that at least some of the SCR functions have been conserved throughout plant kingdom. In Arabidopsis, among its many functions SCR is essential the maintenance of root meristem, the development of root and shoot endodermis and for normal shoot gravitropism. As a result, ser mutants exhibit many phenotypic defects relating to these functions such as, short roots, short hypocotyls, small leaves, shoot agravitropism as well as cell layer deletions in both roots and shoots. We have initiated a genetic screen to identify mutants that suppress ser mutant phenotype(s). In this ser supperssor screen we aim to identify and characterize other components of SCR-regulated pathways. Seeds homozygous for ser1 were mutagenized with EMS, germinated and grown to maturity. Seeds were collected in pools from approximately 100 plants in each pool. All the seeds from the first 29 pools, representing close to 3000 independent lines were screened for suppressor phenotypes. Over 200 potential suppressors were isolated. The majority of the putative suppressors had either longer roots or showed some degree of hypocotyls gravitropism. The potential suppressors were grown to maturity and seeds were collected from all the surviving and fertile plants. We collected seeds from 130 of the primary isolates. All of them were retested for suppressor phenotype and those that still had longer roots or gravitropic hypocotyls were tested for the presence of scrl allele. Six of the primary isolates have been confirmed as potential scr suppressors. Five of these mutants displays hypocotyl gravitropism and only one has a significantly increased root length. The suppressor with the long roots, 24R1, was selected for mapping analysis. 24R1 plants were crossed to scr3, which is in a different genetic background. One quarter of the progeny from the cross has long roots indicating that the suppressor is not allele specific. DNAs isolated from individual plants with long root phenotype were used for mapping using molecular markers. Two to three CAPS markers were used for each of the five Arabidopsis chromosomes. The only linkage was shown for chromosome 4. The mutation responsible for the suppressor phenotype in 24R1 maps to long arm of chromosome 4 about 17.3 cM away from the closest CAPS marker available.
Malaria vaccine development: Genotyping Plasmodium falciparum Merozoite Surface Protein 6 in the Peruvian Amazon. Aaron T. Neal, Stephen J. Jordan, OraLee H. Branch, Julian C. Rayner, University of Alabama at Birmingham, Birmingham, AL 35294.
Malaria is responsible for 1-3 million deaths annually, mostly in children under age five. With drug resistance on the rise, a vaccine seems to be the best solution to combat the most lethal form of the disease, Plasmodium falciparum. This study focuses on P. falciparum Merozoite Surface Protein 6 (PfMSP6), a promising vaccine candidate present on the surface of the P. falciparum parasite. Utilizing samples from P. falciparum infected patients in the Peruvian Amazon, PfMSP6 genotypes were tracked over four consecutive transmission seasons. The longitudinal nature of the study enabled us to compare PfMSP6 genotype frequencies between transmission seasons, villages, and consecutive infections in single individuals. The results of the study will establish the predominance of PfMSP6 genotypes and indicate any immune-related selection pressures; important factors when selecting genotypes to target in a vaccine. The data generated will provide important information to advance a PfMSP6-based malaria vaccine.
Manipulation of the Centaurin Alpha-1 gene in neurons via a Lentiviral Vector. Donna Hill, Dr. Anne Theibert, Dr. Mary Ballestas, Carlene Moore, Jennifer Larrimore, Christopher Chapleau, Sarah Worth,Sharday Ewell, Ireland Scholars Program University of Alabama at Birmingham, Department of Biology and Neurobiology., Birmingham, AL 35294.
Viruses have become an effective and common tool of many cellular and molecular biologists. One of their primary roles in cellular and molecular biology is that of transporting genetic material. Although viruses are useful because they have relatively high transfection efficiency, most are limited by their ability to only tranfect dividing cells. Unfortunately this excludes much brain research and many neurobiologists have not been able to exploit the ability of viruses to transport genetic material. However, lentiviruses are potentially good vectors for transporting genetic material into neurons because they can infect dividing and non-dividing cells. In this study we examine the ability of a lentiviral vector to deliver the centaurin alpha-1 gene. This gene has been implicated as an autism susceptibility gene. Its product, centaurin alpha-1, is a known to bind to Ptdlns (3,4,5) P3-binding protein with high affinity in the brain. It has been implicated in cystoskeletal construction, maintenance and remodeling. Its ability to affect the cytoskeleton allows for effective immunoflourescent examination of morphological changes due to an increase in protein expression. The presence of lentiviruses was detected using GFP. Finally, increased production of centaurin alpha-1 protein was detected using Western Blot analysis.
MARINE FUNGI ON SEAGRASS BEDS IN TWO FLORIDA LAGOONS. Linda A. Collier, Dept. of Marine Sciences Univ. of South Alabama, Mobile, AL 36688 and Dauphin Island Sea Lab, Dauphin Island, AL 36528. Juan L. Mata, Dept. of Biology, University of South Alabama, Mobile AL 36688. Just Cebrian, Dauphin Island Sealab, Dauphin Island AL, 36528 and Dept. of Marine Sciences, University of South Alabama, Mobile AL 36688.
Coastal plant and animal communities have been extensively studied for many years, but their mycological component has been largely neglected or poorly studied until recently. The discipline of marine mycology received only sporadic interest from researchers until the late 1940's. Since then, a total of 444 species have been described worldwide, distributed mostly in the higher groups of ascomycetes and basidiomycetes. A small number of these taxa have been documented for the Gulf Coast of the United States. Because only a few sites have been considered locally, it is unclear how much variation there is in fungal presence between sites. Furthermore, the ecological importance of marine fungi as decomposers of plant detritus is poorly understood compared to that of terrestrial and aquatic environments. Species composition data from more sites is needed as well as studies aimed at examining the ecological importance of marine fungi. The data presented here are from preliminary surveys from two seagrass beds in the North-Central Gulf Coast. One seagrass bed is approximately pristine while the other is highly impacted from wastewater and runoff from nearby homes and a roadway. So far, four species of ascomycetes have been recovered directly from plant material from the pristine site. These results are part of an ongoing graduate research project that aims to document the diversity and abundance of marine fungi associated with seagrass beds.
PANCREATIC STUDIES USING DIFFERENT MODELS EXAMINING REGULATION OF SECRETORY AND METABOLIC FUNCTION. Kimberly A. Hobbs, Debra L. Byrd, Emanuel Waddell, Jeriel L. Johnson, Adriel D. Johnson, Sr., Department of Biological Sciences, University of Alabama in Huntsville, Huntsville, AL, 35899. Jacqueline U. Johnson, Department of Food and Animal Science, Alabama A&M University, Normal, AL 35762.
In vitro culture techniques have been utilized as model systems to examine regulatory mechanisms of pancreatic secretions and metabolism in different animals. Studies in our laboratory have involved an avian pancreatic whole organ culture system used to investigate the role of muscarinic receptors regulating exocrine secretions (Autonomic Neuroscience: Basic & Clinical 105 (2003) 118-130). Recent studies using the embryonic organ culture system measured amylase release during incubation periods of 30 minutes-12 hours revealing loss of viability and morphological degeneration after 12 hours of incubation. Use of selective cholinergic antagonist has revealed that the majority of the receptor population present is functionally similar to the mammalian pancreas muscarinic subtype M3. Studies are being developed which will investigate rodent pancreatic islet cell free radical formation induced by alloxan monohydrate. In addition, we are examining the effects of prophylactic and therapeutic natural products with antioxidant characteristics that will serve as a model for the syndrome similar to type I and type II diabetes mellitus. Isolation of pancreatic cells from Sprague Dawley rats involved 1 mg/ml Type IV collagenase through ductal injection in order to digest tissue into a dispersion and then cultured in an atmosphere of 5% C[0.sub.2] at 37[degrees]C. Pancreatic diabetogenic cells will be examined using SEM techniques. Receptor populations will be examined using the RDAbs [R] Muscarinic M3 Receptor IFA kit for indirect immunofluorescence. Studying the contribution of muscarinic receptors in their regulatory role in endocrine and exocrine pancreatic function using cell cultures for alloxan induced experimental animals can be important in understanding the diabetic state.
POTENTIAL EFFECTS OF CLIMATE CHANGE ON ALABAMA'S PLANT LIFE. L. J. Davenport, Dept. of Biol. & Environmental Sciences and Vulcan Materials Center for Environmental Stewardship & Education, Samford University, Birmingham, AL 35229.
Alabama's native plant life, agricultural crops, forests, and invasive species were examined in light of models of future climate change. In general, tropical species will be enhanced under warmer-wetter conditions, while temperate species will be severely constricted or lost entirely. Mediterranean or arid-based species will flourish under hotter-drier conditions. With climate change, some of Alabama's current ecoregions will shift northward or northeastward; others, based on specific geological formations, will be greatly constricted or disappear. Alabama's future ecoregions will most likely present new associations of plant species, and the state's threatened and endangered plant species will decline further with predicted habitat losses. Temperate-based crops (such as wheat and peaches) will most likely be lost to the state's agriculture with climate change; tropical-based crops (such as tomatoes, melons and citrus) will be enhanced, but only if enough water is available. Under hotter-drier conditions, crop plants will suffer more frequent droughts and forests will experience more frequent fires. In addition to species migrations and losses, Alabama's forests will suffer increased pest problems and increased populations of vines. Alabama's future pest and invasive plant species will be more tropical-based.
Presence of diosgenin in Smilax (Smilacaceae). J. A. Beard, E. G. Dobbins and L. J. Davenport. Department of Biological and Environmental Sciences, Samford University, Birmingham, AL 35229.
Diosgenin, a steroid sapogenin of the saponin dioscin, can undergo oxidation to produce a progesterone-like structure that has been used to synthesize human sex hormones and to treat conditions that are regulated by these hormones. Diosgenin has been shown to be present in many species of Dioscorea (Dioscoreaceae), which includes wild and domesticated yams. Smilax, a very closely related genus in a different family (Smilacaceae), has been shown to contain diosgenin in two species, S. china and S. menispermoidea, but no evidence exists of diosgenin in other Smilax species. This subject is of interest because, due to recent molecular studies, the Smilacaceae and Dioscoreaceae have been placed in different orders (Liliales and Dioscoreales, respectively). By investigating the diosgenin content of two Smilax species, S. bona-nox and S. glauca, insight can be obtained on the chemical similarities and differences of the Smilacaceae and Dioscoreaceae. To investigate the presence of diosgenin in these species, methanol extraction was performed and this extract was further purified through solid phase extraction. The products were then analyzed using mass spectroscopy to verify presence of diosgenin. Our analysis showed that diosgenin was present in both species of Smilax when compared to mass spectroscopy data for a diosgenin standard. Despite the molecular data, this work demonstrate the existence of a chemical basis for a close relationship between Smilacaceae and Dioscoreaceae.
PROGESTERONE IN GYMNOSPERMS. John D. Carson, Dept. of Biology, Samford University, Birmingham, AL 35229. Elizabeth Dobbins Dept. of Biology, Samford University, Birmingham, AL 35229.
Progesterone in Gymnosperms John D. Carson, Elizabeth Dobbins Samford University, Birmingham, Al 35229 The loblolly pine tree (Pinus taeda), used for both pulp and lumber, is the most common source of timber in the southeastern United States. Progesterone was recently described in homogenized extracts from P. taeda (Carson et al., 2008). Progesterone in pulp mill effluent has demonstrably negative effects on the environment, including masculinizing mosquitofish (Gambusia affinis). The current study sought to identify progesterone in wood from other timber species. Eastern white pine (Pinusstrobus) and short leaf pine (Pinus echinata) are two other commercially valuable southeastern timber species. While P. echinata and P. taeda are from the same Subgenus (Pinus), P. strobus is from the Subgenus Strobus. It was expected that, like P. taeda, P. echinata would be likely to contain progesterone, while P. strobes would be less likely. As a control, the more phylogenitically divergent Bald Cyress (Taxodium distichum) of the Family Taxodiaceae was also tested. Homogenized samples of the four woods were methanol extracted, cleaned by filtering and solid phase extraction, and analyzed by liquid chromatography-mass spectroscopy. Contrary to expectations, only P. taeda contained measurable levels of progesterone. Since the P. taeda was collected in Louisiana and the others in Alabama, it is possible that there are regional effects on progesterone concentration in trees. Alternately, there may be a specific physiological purpose for progesterone in P. taeda as yet not understood.
SEX RATIOS AFFECTED BY DAILY WATER TREATMENTS IN A TURTLE WITH TEMPERATURE-DEPENDENT SEX DETERMINATION. Anne Marie LeBlanc and Thane Wibbels, Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294.
A variety of reptiles have temperature-dependent sex determination (TSD) in which the temperatures experienced during incubation appear to be the main factor affecting sex determination. Previous reports have suggested that sex determination in species with TSD may also be influenced by the hydric environment given certain laboratory conditions. However, other reports suggest that this relationship remains uncertain and currently, it is generally accepted that that the hydric environment has no role in sex determination. Recently, this question has resurfaced since sex rations produced from sea trutle nests on natural nesting beaches do not always match the sex rations predicted from laboratory studies using constant incubation temperatures. This suggests that other factors may be influencing sex determination. In order to examine the hydric environment's effects on TSD, the current study applied water treatments to eggs of the red-eared slider turtle. Eggs were incubated at a temperature (29.1 degrees Celcius) which produced predominantly females. Eggs were divided between control and experimental groups. The experimental groups received a daily water treatment (0.77 ml ddH20 per egg per day administered externally) during the temperature sensitive period. The control groups produced approximately 90% females (n = 53). The experimental groups (n = 84) produced significantly more males than the control groups (P < 0.05). The results suggest that water treatments, applied daily directly to the egg, can influence TSD. This could have implications when examining sex ratios from natural nesting beaches that are periodically exposed to rain and have the potential to alter management strategies.
Shear Bond Strength of Three Adhesives to Enamel and Dentin. P. JAMPANI, D. CAKIR, J. BURGESS, and L. RAMP, University of Alabama at Birmingham, Birmingham, AL 35294.
Bonding agents have evolved from total etch to two bottle and finally one bottle self etching systems. These newly developed systems may not bond as well to enamel or dentin as total etch materials. OBJECTIVES: To measure and compare the shear bond strength of three adhesives to enamel and dentin. METHODS: 60 extracted, intact, human molars were divided into two groups and wet ground with 600 grit to obtain flat enamel (E) and dentin (D) surfaces. The materials used were Adper Scotchbond SE (3M ESPE) a two component self etching adhesive, Adper Easy Bond (3M ESPE) a single component self etching adhesive and Adper Single Bond Plus (3M ESPE) a total etch one bottle adhesive. The adhesives were applied. A plastic tube (diameter~1.5mm) filled with composite-resin (Z100) was placed over the adhesive and cured for 40 seconds with a curing light (Fusion, output > 800 Mw/[cm.sup.2]). Samples (n=10) were stored in water for 24 hours at 37[degrees]C in an incubator. Specimens were placed in a special fixture mounted on a Universal testing machine (INSTRON, model number 5565) and loaded to failure at a crosshead speed of lmm/min. The failure load was converted to bond strength by dividing by the bonding area. The data were analyzed with 2-factor ANOVA (p=0.05). RESULTS: (n=10) (Mean[+ or -]SD). Adper Scotchbond SE Adper Easy Bond Single Bond Plus E 18.9[+ or -]6 19.2[+ or -]5 22.6[+ or -]7 D 23[+ or -]5 25.7[+ or -]5 26.1[+ or -]6 CONCLUSIONS: No significant difference was shown between the substrate or the bonding agent (p > .05). Early in vitro results show that the self etching adhesives show promise as effective bonding agents.
SHEAR BOND STRENGTH OF THREE ADHESIVES TO ENAMEL,GROUND-ENAMEL AND DENTIN.P. KADAM, R.S. ZADEH, D. CAKIR, J. BURGESS, and L. RAMP, University of Alabama at Birmingham, AL 35294.
Bonding agents continue to develop with basic changes from a total etch to self etching systems. However the self etching systems have a higher pH which decreases the bond to enamel. OBJECTIVES To measure and compare the shear bond strength of two experimental self-etch adhesives with a commercially available self-etching adhesive on enamel, ground-enamel and dentin. METHODS 90 extracted human molars were divided into 3 groups, 30 each. For the enamel group flattest surface was used. For the two other groups, the teeth were ground with a 600-grit wet SiC abrasive wheel to obtain flat enamel and dentin bonding surfaces. The adhesives used were Clearfil SE (Kuraray), SCB Experimental O-(Coltene Whaledent), SCB experimental P-(Coltene Whaledent). The adhesives were applied according to manufacturer's instructions. A plastic tube filled with composite-resin (Synergy/Coltene Whaledent) was placed over the adhesive and polymerized for 40s with Coltolux LED curing light (750 Mw/cm2). Samples were stored in water for 24 hours at 37[degrees]C in an incubator before testing. Specimens (n= 10) were loaded until failure at a crosshead speed of 1mm/min on a Universal testing machine (INSTRON, 5565). The data were analyzed with 2-factor ANOVA and Tukey/Kramer post-hoc tests (p=0.05). RESULTS: Mean[+ or -]SD in MPa UNGROUND ENAMEL GROUND ENAMEL DENTIN Clearfil SE 26.8[+ or -]4 31.6[+ or -]4 28.7[+ or -]2 SCB Experimental O 19.7[+ or -]4 23.6[+ or -]5 24.9[+ or -]3 SCB experimental P I7.9[+ or -]4 20.8[+ or -]2 21.7[+ or -]3 CONCLUSIONS Based on the results of this study, Clearfil SE showed higher shear bond strength for all three substrates (p < 0.05). Significant differences were found between dentin, ground enamel and enamel.
SHEAR BOND STRNGTH OF SELF ADHESIVE CEMENTS.T. GHUMAN, R.S. ZADEH, D. CAKIR, J. BURGESS, L.C. RAMP, and P. BECK, University of Alabama at Birmingham, AL 35294.
Self adhesive cements are becoming popular due to the reduced number of steps required for cementation. New self adhesive cements continue to develop and improve but further testing is required. OBJECTIVE: To measure shear bond strength to zirconia disks of seven commercially available and a new adhesive cements. METHODS: The surfaces of 80 Cercon dises were wet ground with 320-grit SiC abrasive paper for lmin, followed by air-abrasion with 25mm AL203. They were randomly assigned to eight groups (n=10). Light-cured composite rods of Z100 (d~2.35mm) were prepared and abraded with 25mm AL203 for 2s, followed by application of Clearfil SE bonding agent (light-cured for 20s). Rods were cemented to Zirconia using self-adhesive cements (G-Cem[G], RelyX Unicem Aplicap[UA], RelyX Unicem Clicker[UC], Biscem[B], Multilink Sprint [MS], Maxcem[M], Experimental Cement [K], Panavia F2.0 [P]) following manufacturer's instruction with constant weight of 400g and cured for 20s with Coltolux light (750 Mw/cm2). Samples were incubated at 37C for 24h, thermocycled between 6-600C with a 15s dwell time for 1000 cycles. They were debonded using a universal testing machine (Instron 5565) with crosshead speed of lmm/min. The results were analyzed with ANOVA followed by Tukey/Kramer (p=0.05). Samples were evaluated under SEM. RESULTS: Mean [+ or -] SD in MPa. G UA UC B MS M K P 11.4 [+ or -]1 14[+ or -]4 12.4[+ or -]4 8.3[+ or -]2 8.6 [+ or -] 2 5.8 [+ or -]11 4.8 [+ or -]5 10.5 [+ or -] 2 Tukey/Kramer post hoc test showed no significant difference (p > 0.05) between experimental cement (K) and G-Cem, Panavia F 2.0, Unicem cements.
Self adhesive cements continue to develop but further improvement should be continued
TEMPERATURE DEPENDENT VITELLOGENIN MRNA PRODUCTION IN THE MALE WESTERN MOSQUITOFISH, GAMBUSIA AFFINIS. Paul D. Melvin*, III, Dept. of Natural Sciences, Clayton State Univ., Morrow, GA 30260 and Robert Angus, Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294.
Many anthropogenic compounds with estrogenic activity have been detected in aquatic environments. Vitellogenin (VTG), an egg yolk protein produced by the liver in oviparous female vertebrates in response to estrogen, is not normally detectable in the serum of males. Various studies have indicated that environmental estrogens can induce VTG protein and mRNA in males of a variety of aquatic vertebrate species, including the western mosquito fish, Gambusia affinis. If the presence of VTG mRNA in males is to serve as a reliable estrogen biomarker, it is important to understand other factors that influence its production. Although the regulation of vitellogenesis is poorly understood, previous observations in our lab have suggested that temperature plays an important role. We hypothesize that estrogenic induction of VTG mRNA in males will decrease as water temperature decreases. In this study, male G. affinis -ethinylestradiol via diet at a concentration of (5 [micro]g/g of[alpha]were exposed to 17 food) for a period of one week. This concentration was previously shown to strongly induce VTG production in one week at 24 [degrees]C. During exposure, the fish were kept at a constant waC. VTG[degrees]ter temperature of 16, 20, or 24 ( [+ or -]. 1 [degrees]) induction at the mRNA level was examined by RT-PCR. It was shown there was significant downregulation of VTG mRNA induction at lower temperatures. These results demonstrate that temperature strongly affects the extent to which Gambusia affinis produces VTG mRNA in response to estrogen exposure. This work was supported in part by the Alabama Academy of Science.
The Fishes of Oak Mountain State Park David M. Frings, Dr. Robert Stiles, and Dr. Jason Heaton Samford University. Birmingham, AL 35229.
Oak Mountain State Park is located in the central portion of Shelby County, Alabama in a highly urbanized area of the state. The parks drainage system is included in the Cahaba River basin which has four primary tributaries that transect the park; Dry Brook, Hogpen Creek, Cahaba Valley Creek, and Peavine Branch. The purpose of this study is to collect data on the fish that occur in the park and compile a photographic record of each species. The study is a portion of a larger study by Samford University to document all of the fauna in Oak Mountain State Park so that there will be a baseline of data for future conservation efforts and planning. During this phase of the fish study, sampling was conducted in Dry Brook and Hogpen Creek. The second phase of the fish study will continue sampling in these tributaries and expand the sampling to Cahaba Valley Creek and Peavine Branch. Thirteen species of fish were collection during 2007 and the first quarter of 2008 that represent six families.
TORUS-BEARING PIT MEMBRANES IN THE WOOD OF PICCONIA (OLEACEAE). Kyle Paris, Charles Holloway, Roland Dute, Auburn University, Auburn, AL 36849. Steven Jansen, Jodrell Laboratory, Royal Botanic Gardens, Kew, UK.
Torus-bearing pit membranes that connect water-conducting cells are common in the wood of conifers and Ginkgo, but uncommon in flowering plants. Osmanthus (Oleaceac) is one of the few genera of the latter known to have pit membranes with tori. Recent molecular studies indicate a close relationship between Osmanthus and the genera Nestegis, Phillyrea, Notelaea, and Picconia. Investigations in our laboratory show the first three genera to lack tori. Only the two species of Picconia, P. excelsa and P. azorica, possess these structures. In P. excelsa, tori are common; in P. azorica they are rare and difficult to locate. Torus-bearing pit membranes in P. excelsa exist in both early and late wood. The torus on a pit membrane is circular, centrally located, and has a diameter greater than that of its adjacent pit aperture. Further studies are needed to clarify whether the torus represents a shared, primitive structure in this portion of the Olive Family, or whether it has evolved multiple times.
USING BACKBONE AMIDE H/D EXCHANGE MASS SPECTROMETRY TO STUDY PROTEIN STRUCTURE AND DYNAMICS. Laura S. Busenlehner, Department of Chemistry, The University of Alabama, Tuscaloosa, AL 35487.
The backbone of a protein contains a unique set of tandem chemical reporters, the amide NH group. Amide hydrogen/deuterium exchange mass spectrometry (H/D exchange MS) is emerging as an attractive technique that has been used for over three decades to investigate protein structure and dynamics. H/D exchange MS has certain advantages in that there is no practical size limitation to the protein, the working protein concentrations can be in the sub-micromolar range, and the technique can be easily extended to membrane proteins. Spatial resolution is typically achieved by proteolysis and mass analysis of the peptide fragments. Amide hydrogen/deuterium exchange kinetics can vary dramatically within a protein due to hydrogen bonding, solvent accessibility, and backbone flexibility. Therefore, the amide exchange rate is highly dependent on protein structure, as well as dynamics. The theory and experimental design of a typical H/D exchange MS experiment will be presented, along with several examples of applications of the technique. In particular, the advancement into membrane protein structure and protein-ligand interactions will be highlighted.
Herpetology at Jacksonville State University. George Cline, James Rayburn, and Chris Murdock. Biology Department, Jacksonville State University, 700 Pelham Road North, JAcksonville, AL 36265-1602
Herpetology research in Alabama has historically been driven by research at larger, Ph. D. granting institutions. Three faculty at Jacksonville State University now represent a core of researchers with complementary research methods that have herpetology interests. Dr. George Cline is a field herpetologist whose research topics include frog communication, herpetological community structure, herptile conservation biology, and amphibian and reptile natural histories. He is particularly interested in temporal and acoustical partitioning in frog communities. Dr. James Rayburn is an ecotoxicologist who's research interests lie in amphibian development and amphibian metamorphisis. He uses Frog Embryo Teratogenesis Assay - Xenopus (FETAX) as one of his research techniques to study the effects of chemicals and other environmental factors on amphibians, and biomarkers to study vitellogenin induction by anthropogenic estrogens. Research topics currently being addressed in Dr. Chris Murdock's laboratory include regulatory mechanisms within the hypothalamus-pituitary-gonad axis of snakes, along with possible temperature effects on sex determination in amphibians. In these studies herpetology is addressed from a molecular biology/biotechnology perspective in order to address the underlying physiological and development cascades in the reproductive axis of these organisms. Specific techniques currently being utilized include: PCR, gene cloning, quantitative real-time PCR, and gene sequencing. The complementary approach to herp research at JSU represents a synergistic collaboration among individuals with diverse skills. This unique combination of faculty and skills offers exciting new ways to approach herpetological research.
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|Publication:||Journal of the Alabama Academy of Science|
|Date:||Apr 1, 2008|
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