Biology Commons^™

Gestational Diabetes And Its Effects On The Fetus, Todd Pollack

The Science Journal of the Lander College of Arts and Sciences

Although the common effects of gestational diabetes on the fetus are known, the outcome of a diabetic gestation is ambiguous. There is concern for complications in the fetus at delivery due to enlarged size of the fetus, as well as concerns for birth defects, fetal distress, diabetes and obesity. Yet, although there is a correlation in the previous disorders and gestational diabetes, many of the mechanisms that cause these complications are unknown. By studying the pathology of gestational diabetes, researchers have learnt that the placenta controls fetal growth and provides a great deal of protection for the fetus. Therefore, many …

Reproductive Isolation Between Two Sympatric Simultaneous Hermaphroditic Shrimp, Lysmata Wurdemanni And L. Boggessi, Dong Zhang, Junda Lin, Jörg D. Hardege, Andrew L. Rhyne

Arts & Sciences Faculty Publications

To investigate pre- and post-zygotic isolation between two sympatric and phylogenetically related species of Lysmata shrimp, two assays were conducted in the laboratory: (1) no specific mate choice where mating between the two species was ‘forced’; (2) specific mate choice or preference where a female had a choice between conspecific and heterospecifc males. Behavioural studies reveal that female L. wurdemanni accepted only conspecific male shrimp, whereas L. boggessi females would mate with an interspecific male if there was no conspecific male present. When males of both species were present, L. boggessi females always mated with the conspecific male. Male L. …

Factors Affecting Breeding Territory Size And Placement Of The Florida Grasshoper Sparrow (Ammodramus Savannarum Floridanus), Jill Aldredge

Electronic Theses and Dissertations

For most taxa, maximizing fitness depends on maintaining access to adequate resources. Territories provide exclusive use of resources for an individual or a family group, thus facilitating successful reproduction. The economic defensibility of a territory depends on the quality, abundance, and distribution of its resources as well as the amount of competition that an individual must endure to maintain exclusive access. The benefits of defense must outweigh the costs for territoriality to be profitable. Territory owners may benefit from territories with high quality resources, but they also may incur greater costs defending these resources from competitors. In contrast, territories with …

Structural Studies Of Talin-Mediated Integrin Activation, Esen Bakhautdin

ETD Archive

Activation of heterodimeric (alpha/beta) integrin transmembrane receptors by the cytoskeletal protein talin is essential for many important cell adhesive responses including cell-extracellular matrix contact, cell motility and survival. A key step in this process involves interaction of phosphotyrosine-binding (PTB) domain in the N-terminal head of talin (talin-H) with integrin beta3membrane-proximal cytoplasmic tails (beta-MP-CTs). Compared to talin-H, intact talin exhibits low potency in inducing integrin activation. Using TROSY NMR spectroscopy, we found that the large C-terminal rod domain of talin (talin-R) interacts with talin-H and allosterically restrains talin in a closed conformation. Structural, mutational, and biochemical analyses demonstrate that talin-R specifically …

Homeostatic Regulation Of Interleukin-4-Mediated Cell Signaling, Rikhia Chakraborty

ETD Archive

Cytokines are intracellular messengers that activate multiple signaling pathways and regulate cell survival, differentiation, migration, apoptosis and immune responses. We are investigating the homeostatic control of cytokine-mediated cell signaling using interleukin-4 (IL-4) as a model cytokine. Protein tyrosine phosphorylation is essential for cytokine-dependent signal transduction through the Janus Kinase-Signal Transducer and Activator of Transcription (Jak-STAT) pathway. Therefore, protein tyrosine dephosphorylation is a key mechanism providing the homeostatic control of the pathway. Here, we have shown for the first time that immediately following ligand-dependent activation, IL-4 receptor induces an intracellular calcium flux via insulin receptor substrate (IRS)-phosphoinositide 3-kinase (PI3K)-phospholipase C (PLC)-gamma …

Role Of Kcnma1 In The Pathogenesis Of Gepd Syndrome, Wei Du

ETD Archive

No abstract provided.

Regulation Of Monocyte Nadph Oxidase;Role Of Pattern Recognition Receptors, Deena H. Elsori

ETD Archive

No abstract provided.

Regulation Of Apoptosis By The Muscle Regulatory Transcription Factor Myod, Terri J. Harford

ETD Archive

We have previously reported that the level of MyoD expression correlates with the level of apoptosis that occurs in a subpopulation of skeletal myoblasts induced to differentiate by serum withdrawal. Herein we document that MyoD expression dictates the apoptotic threshold in myoblasts and fibroblasts in response to a variety of apoptotic stimuli. Specifically, re-expression of MyoD in skeletal myoblasts rendered defective for both differentiation and apoptosis by the expression of oncogenic Ras restores their ability to undergo both differentiation and apoptosis in response to serum withdrawal. Further, using a fibroblast cell line expressing an estrogen receptor:MyoD fusion protein, we have …

Overcoming Barriers To Natural Orifice Translumenal Endoscopic Surgery (Notes), Steve J. Schomisch

ETD Archive

Natural Orifice Translumenal Endoscopic Surgery (NOTES) avoids skin incisions by accessing the abdominal cavity through natural orifices. Benefits include less pain, fewer complications and no scars. The aims of this study were to evaluate safety and efficacy of access techniques for natural orifice surgery, to investigate safety and efficacy of closure methodologies and to compare the inflammatory response induced by NOTES with that following conventional surgery. Access techniques were evaluated for safety and efficacy by measuring resultant injury and time required to access the peritoneal cavity in an acute porcine model. Four different gastrotomy closure modalities were evaluated for safety …

Myf5 Does Not Induce Apoptosis In Skeletal Myoblasts But Is Regulated By Oncogenic Ras Expression, Alexander Phillip Talarico

ETD Archive

Skeletal myogenesis is initiated by a family of muscle regulatory factors (MRFs) composed of the transcription factors MyoD, Myf5, MRF4, and myogenin. Of these, MyoD was the first discovered, is the most studied, and plays a well-characterized role in skeletal myoblast determination and differentiation. Our laboratory has also discovered that MyoD plays an important role in the apoptotic process that occurs in a subpopulation of myoblasts induced to differentiate. Expression of oncogenic Ras is known to inhibit myoblast differentiation and to decrease the expression of MyoD mRNA and protein. Our laboratory was the first to report that expression of oncogenic …

Cloning And Expression Of Aquaporin In The Antennal Gland Of Crayfish, Procambarus Clarkii, Yang Gao

Browse all Theses and Dissertations

Aquaporins (AQPs) are responsible for transferring water and other small molecules across the cell membrane. Relatively little research has been conducted on AQPs in crustaceans. To study the AQPs in crayfish, I hypothesis that 1) AQP is expressed in the antennal gland (kidney analogue) of crayfish; 2) crayfish AQP will show greater expression in tissues (gill and antennal gland) associated with volume regulation; 3) AQP mRNA expression in antennal gland and gill will increase in premolt and decrease in postmolt compared with intermolt level. RT-PCR and Real-time PCR assay were applied to test the hypothesis. A partial AQP gene was …

Functional Morphology And Fluid Interactions During Early Development Of The Scyphomedusa Aurelia Aurita, K. E. Feitl, A. F. Millett, Sean Colin, John O. Dabiri, John H. Costello

Arts & Sciences Faculty Publications

Scyphomedusae undergo a predictable ontogenetic transition from a conserved, universal larval form to a diverse array of adult morphologies. This transition entails a change in bell morphology from a highly discontinuous ephyral form, with deep clefts separating eight discrete lappets, to a continuous solid umbrella-like adult form. We used a combination of kinematic, modeling, and flow visualization techniques to examine the function of the medusan bell throughout the developmental changes of the scyphomedusa Aurelia aurita. We found that flow around swimming ephyrae and their lappets was relatively viscous (1 < Re < 10) and, as a result, ephyral lappets were surrounded by thick, overlapping boundary layers that occluded flow through the gaps between lappets. As medusae grew, their fluid environment became increasingly influenced by inertial forces (10 < Re < 10,000) and, simultaneously, clefts between the lappets were replaced by organic tissue. Hence, although the bell undergoes a structural transition from discontinuous (lappets with gaps) to continuous (solid bell) surfaces during development, all developmental stages maintain functionally continuous paddling surfaces. This developmental pattern enables ephyrae to efficiently allocate tissue to bell diameter increase via lappet growth, while minimizing tissue allocation to inter-lappet spaces that …

Caspase Cleavage Of The Amyloid Precursor Protein Is Prevented After Overexpression Of Bcl-2 In A Triple Transgenic Mouse Model Of Alzheimer’S Disease, Debra K. Kumasaka, Veronica Galvan, Elizabeth Head, Troy T. Rohn

Biology Faculty Publications and Presentations

A recent study demonstrated the lack of beta-amyloid (Aβ) plaque formation and accumulation of the amyloid precursor protein (APP) in a triple transgenic mouse model of Alzheimer’s disease (3xTg-AD) following overexpression of the anti-apoptotic protein, Bcl-2 (Rohn et al., J. Neurosci. 28: 3051-9, 2008). The supposition from that study was the accumulation of APP resulted from a decrease in caspase-mediated processing of APP. To determine a direct role for the caspase-cleavage of APP in 3xTg-AD mice, we designed a site-directed caspasecleavage antibody to APP and demonstrated it is a specific marker for caspase-cleaved APP. Application of this antibody revealed neuronal …

Afforestation Alters The Composition Of Functional Genes In Soil And Biogeochemical Processes In South American Grasslands, Sean T. Berthrong, Christopher W. Schadt, Gervasio Piñeiro, Robert B. Jackson

Scholarship and Professional Work - LAS

Soil microbes are highly diverse and control most soil biogeochemical reactions. We examined how microbial functional genes and biogeochemical pools responded to the altered chemical inputs accompanying land use change. We examined paired native grasslands and adjacent Eucalyptus plantations (previously grassland) in Uruguay, a region that lacked forests before European settlement. Along with measurements of soil carbon, nitrogen, and bacterial diversity, we analyzed functional genes using the GeoChip 2.0 microarray, which simultaneously quantified several thousand genes involved in soil carbon and nitrogen cycling. Plantations and grassland differed significantly in functional gene profiles, bacterial diversity, and biogeochemical pool sizes. Most grassland …

A Global Meta-Analysis Of Soil Exchangeable Cations, Ph, Carbon, And Nitrogen With Afforestation, Sean T. Berthrong, Esteban G. Jobbagy, Robert B. Jackson

Scholarship and Professional Work - LAS

Afforestation, the conversion of non-forested lands to forest plantations, can sequester atmospheric carbon dioxide, but the rapid growth and harvesting of biomass may deplete nutrients and degrade soils if managed improperly. The goal of this study is to evaluate how afforestation affects mineral soil quality, including pH, sodium, exchangeable cations, organic carbon, and nitrogen, and to examine the magnitude of these changes regionally where afforestation rates are high. We also examine potential mechanisms to reduce the impacts of afforestation on soils and to maintain long-term productivity.

Across diverse plantation types (153 sites) to a depth of 30 cm of mineral …

The Mechanism Of Expansion And The Volatility It Created In Three Pheromone Gene Clusters In The Mouse (Mus Musculus) Genome, Robert C. Karn, Christina M. Laukaitis

Scholarship and Professional Work - LAS

Three families of proteinaceous pheromones have been described in the house mouse: androgen-binding proteins (ABPs), exocrine gland–secreting peptides (ESPs), and major urinary proteins (MUPs), each of which is thought to communicate different information. All three are encoded by large gene clusters in different regions of the mouse genome, clusters that have expanded dramatically during mouse evolutionary history. We report copy number variation among the most recently duplicated Abp genes, which suggests substantial volatility in this gene region. It appears that groups of these genes behave as low copy repeats (LCRs), duplicating as relatively large blocks of genes by nonallelic homologous …

Wolf Spiders Of The Pacific Region: The Genus Zoica (Araneae, Lycosidae), Volker W. Framenau, James W. Berry, Joseph A. Beatty

Scholarship and Professional Work - LAS

The wolf spider genus Zoica Simon 1898 is currently known only from the Indo-Australasian region, including India in the west to northern Western Australia and Papua New Guinea in the east. Here we extend the known distribution of the genus into the Pacific region by describing two new species, Z. carolinensis new species from the Caroline Islands, Federated States of Micronesia, and Z. pacifica new species from the Republic of the Marshall Islands.

Assessment Of River Herring And Striped Bass In The Connecticut River: Abundance, Population Structure, And Predator/Prey Interactions, Justin P. Davis, Eric T. Schultz, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring A. aestivalis, collectively referred to as river herring, have declined in the Connecticut River. An explanatory hypothesis for these declines is that predation pressures have increased as a result of recent increases in abundance of sympatric striped bass Morone saxatilis. We sampled river herring and striped bass from the stretch of the Connecticut River between Wethersfield, CT and Holyoke, MA during the vernal migration seasons of 2005-2008. The objectives of the sampling program were to assess abundance, temporal/spatial distribution, and population structure of both river herring and striped bass, …

Tthe Immature Stages And Natural History Of Antirrhea Adoptiva Porphyrosticta (Watkins, 1928) In Eastern Ecuador (Lepidoptera, Nymphalidae, Morphinae), Harold F. Greeney, Philip J. Devries, Carla M. Penz, Rafael B. Granizo-T, Heidi Connahs, John O. Stireman Iii, Thomas R. Walla, Lee A. Dyer

Biological Sciences Faculty Publications

Here we describe the immature stages and ecological associations of Antirrhea adoptiva porphyrosticta Watkins, 1928 (Lepidoptera:Nymphalidae:Morphinae). The cloud forest bamboo, Chusquea scandens Kunth (Bambusoidea: Poaceae), serves as the larval food plant for this butterfly in eastern Ecuador, the first hostplant record for Antirrhea outside the family Arecaceae. The larvae of A. adoptiva porphyrosticta are superficially similar to those of other Antirrhea species. We also provide observations on adult and larval behavior. Caterpillars of this butterfly species are parasitized by tachinid flies, as well as by Ichneumonidae and a newly described braconid wasp.

Viability Of Subitaneous Eggs Of The Copepod, Acartia Tonsa (Dana), Following Exposure To Various Cryoprotectants And Hypersaline Water, Cortney L. Ohsa, Andrew L. Rhyne, Erik Stenn

Arts & Sciences Faculty Publications

Subitaneous eggs were obtained from monocultures of the calanoid copepod Acartia tonsa (Dana), Gulf of Mexico strain. Eggs were exposed to methanol, ethylene glycol, propylene glycol, glycerine, and DMSO at 0.0, 0.1, 0.5, 1.0, 2.0, and 5.0 M and hypersaline water at 50, 75, 100, 150, and 200 g/L. Treatments were evaluated after 10 and 20 min of exposure and at 4 and 26 °C. Viability (percent hatched) was determined after 24 h of incubation in 35 g/L saltwater at 26 °C.

Methanol, ethylene glycol, and glycerine had high viability up to 2M, and all experienced large decreases at 5M …

Seal Bounties In Maine And Massachusetts, 1888 To 1962, Barbarai Lelli, David Harris Ph.D, Aboueissa Abouel-Makarim

Faculty Publications

Maine and Massachusetts paid bounties on seals during the 19th and 20th centuries. To determine the number of seals killed for bounty, we examined historical records of bounty claims, and used geographic information systems and multiple linear regression to find predictors of places where large numbers of bounties were paid. We found records of 24,831 bounties paid in Maine (1891-1945) and 15,690 in Massachusetts (1888-1962), Considering possible fraud, missing data, and seals struck and lost, this suggests that 72,284 to 135,498 seals were killed in the bounty hunt, probably enough to account for regional declines in seal populations. Larger numbers …

Erk Activation Requires Cam Kinases In Mcf-7 Breast Cancer Cells, John M. Schmitt, Ellen Abell

Faculty Publications - Department of Biological & Molecular Science

Abstract A key signaling pathway involved in regulating cell growth and proliferation throughout the body is the ERK signaling pathway. ERK is activated via numerous pathways including intracellular calcium release downstream of G-Protein Coupled Receptors (GPCRs). Carbachol, a GPCR-agonist, both increases intracellular calcium and ERK activation in MCF-7 cells. ERK activation and control of cell growth may act through the transcription factor Elk-1. Our goal was to elucidate the specific proteins and kinases upstream of ERK in MCF-7 cells treated with carbachol. Secondly, we wanted to investigate the potential involvement of Elk-1 downstream of ERK. Carbachol treatment of MCF-7 cells …

Cam Kinase Kinase Control Of Prostate Cancer Cell Survival, John M. Schmitt, Brendon Hart

Faculty Publications - Department of Biological & Molecular Science

Abstract AKT has been implicated in promoting cell survival within certain cells. Current research has shown that hormones that increase the concentration of intracellular calcium can activate AKT that in turn leads to cancer cell survival. Interestingly, LNCaP cells express the M3-subtype of GPCR's that may couple to increases in intracellular calcium and activation of the Ca2+/Calmodulin-dependent Protein Kinases (CaM Ks). Specifically CaM Kinase Kinase (CaM KK) phosphorylates its direct substrates CaM Kinase I, CaM Kinase IV, and AKT. AKT promotes cell survival through phosphorylation of its target BAD that prevents caspase activation. Our goals were to examine the mechanism …

Primary Culture Of Isolated Cardiac Myocytes From The Bullfrog, Rana Catesbeiana, Jeff Duerr, Silvianne Luft

Faculty Publications - Department of Biological & Molecular Science

Comparative vertebrate studies into physiological responses to adverse conditions can yield great insight into the design of robust systems and provide fundamental knowledge of stress adaptations. The classically studied cellular stress response is the mitogen-activated protein kinase (MAPK) pathway. Prior investigations in our laboratory indicated a differential response of MAPK family activation to progressive dehydration in cardiac tissue from two species of anuran amphibians: Rana catesbeiana and Bufo marinus. Western blot analysis indicated that pERK increased by three-fold in Bufo and 2-fold in Rana. pJNK levels remained unchanged in Bufo whereas in Rana increased by 50%. pp38 did not exhibit …

Element Stoichiometry Of Ochromonas Danica As A Function Of Growth Rate And Temperature, Savannah Simonds

Biology Theses - Archive

The microbial loop stresses the importance of flagellated protozoa as predators of bacteria and regenerators of nutrients, the outcome of which affects higher trophic levels. The element stoichiometry of flagellates has only been examined while feeding upon bacteria or phytoplankton. In this study, the element stoichiometry of the protozoan flagellate, Ochromonas danica, was determined while growing osmotrophically thus eliminating the potential errors due to element contributions of prey in food vacuoles. The element and nucleic acid content of the flagellate were examined under a range of environmentally relevant temperatures and growth rates using chemostat cultures. Growth rate was the driving …

Diversity And Community Organization In The Periphyton Of Recirculating Streams Channels Are Defined By Current Velocity And Nutrient Supply, Chad A. Larson

Biology Dissertations - Archive

In a series of experiments taking place in recirculating artificial stream channels, periphyton communities growing on ceramic tiles were subjected to variations in current velocity and nutrient supply. The first experiment used stream water and manipulated current velocity, subjecting periphyton communities to either high or low current velocities (30 and 10 cm * sec-1 respectively), while in experiments 2-4, modified WC media was used and periphyton communities subjected to different nutrient (low and high) and current regimes (low, high, and variable flow). Each experimental run lasted 35 days. In all experiments, greater species richness of periphyton communities was observed in …

Natural Hybridization And Speciation In Toads Of The Anaxyrus Americanus Group., Brian E. Fontenot

Biology Dissertations - Archive

The goal of speciation research is to elucidate the processes that lead to the formation of new species. Examining natural hybridization and the evolution of reproductive isolating barriers provides an opportunity to understand the dynamic processes that occur before, during, and after speciation events. Here, I use true toads of the Anaxyrus americanus group to examine the effects of natural hybridization on (1) the evolution of reproductive isolation using previously published laboratory hybridization data on multiple species within the family Bufonidae, (2) morphological variation using morphometric analysis of known Anaxyrus americanus group hybrids, and (3) molecular variation and genetic population …

Evolutionary Morphology Of The Speckled Rattlesnakes (Viperidae: Crotalus Mitchellii Group), Jesse Malcolm Meik

Biology Dissertations - Archive

I examined various facets of morphological variation and evolution in the speckled rattlesnake (Crotalus mitchellii) species group. I performed three separate, but related, studies pertaining to the following topics: body size of putative ancestral source species and patterns of snake occupancy on islands in the Baja California region, the evolution and prevalence of gigantism and dwarfism among insular populations of speckled rattlesnakes, and the climatic correlates of scalation patterns in speckled rattlesnakes.I examined the influence of body size of mainland source species on insular distribution patterns by using a species index that weights isolation of islands while simultaneously penalizing island …

Morphology And Habitat Use Among Insular Populations Of The Lizard Anolis Lemurinus From The Cayos Cochinos Archipelago Of Honduras, Michael Latter Logan

Biology Theses - Archive

In Honduras, Anolis lemurinus is distributed along the Atlantic versant of the mainland and on the Caribbean island system consisting of the Bay Islands and Cayos Cochinos archipelagos. In the Cayos Cochinos, A. lemurinus occurs on the two largest islands, Cayo Mayor and Cayo Menor, which are separated by less than 1km. A previous study using genetic (amplified fragment-length polymorphisms) and morphometric (mass and SVL) data suggested that populations of A. lemurinus in the Cayos Cochinos did not differ from each other (Klutsch et al. 2007). Despite the extremely close proximity of Cayo Mayor and Cayo Menor populations, I hypothesized …

How Soil Nutrient Availability Affects Plant Sexual Reproduction And Seedling Recruitment In Alaskan Dry Heath Tundra: Implications For Response To Climate Change, Carol Moulton

Biology Theses - Archive

The harsh growing conditions of the arctic biome, in particular low temperatures and soil nutrient availability, restrict the growth and reproduction of arctic plant species. Recent and ongoing changes in climate are increasing air and soil temperatures in these ecosystems, thus affecting decomposition rates of arctic soils. As decomposition increases, nutrients that are currently immobilized in the soil organic layer become available to nutrient-limited tundra plants. Plant species within the tundra communities then compete for the newly available nutrients, potentially causing a shift in community composition. As an important component of plant life cycles, seeds provide new individuals and genetic …