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Mechanism By Which Insulin And Its Mimetics, Selenate And Vanadate, Regulate Glucose-6-Phosphate Dehydrogenase Gene Expression, Sanjay M. Jivraj

Masters Theses

Glucose-6-phosphate dehydrogenase (G6PDH) is a key enzyme of the pentose phosphate pathway. It controls the carbon flow through this pathway, producing reducing equivalents in the form of NADPH to meet the cellular need for reductive biosynthesis and the maintenance of the cellular redox state. Hepatic expression of G6PDH has been shown to be regulated by hormones, nutrients and some growth factors, however the mechanism by which these factors regulate G6PDH gene expression has not been characterized. Here we investigate the mechanism by which insulin and its mimetics, selenate and vanadate, regulate G6PDH gene expression.

Insulin exerts its tissue specific affect …

Stage-Dependent Expression Of Target-Derived Influences Stimulates Axon Outgrowth In Hirudo Medicinalis, Tina M. Harik

Masters Theses

Our lab has been investigating the development of neuronal phenotype and circuitry in Hirudo medicinalis. Early in embryogenesis the heart excitor (HE) motor neuron selectively extends multiple arbors into the body wall prior to heart tube (HT) formation. HE contact with HT primordium at later stages of development results in remodeling such that arbors are elaborated on the HT, while those in the body wall are retracted. HT-derived cues are necessary for HE remodeling (Jellies, 1995. Am. Zool. 35:529; Jellies and Kopp, 1995. Invert. Neurosci. 1:145). HT and body wall explants were co-cultured to investigate the possible influences of …

Identification Of A Family Of Zinc Transporter Genes From Arabidopsis That Respond To Zinc Deficiency, Natasha Grotz, Tama Fox, Erin Connolly, Walter Park, Mary Lou Guerinot, David Eide

Dartmouth Scholarship

Millions of people worldwide suffer from nutritional imbalances of essential metals like zinc. These same metals, along with pollutants like cadmium and lead, contaminate soils at many sites around the world. In addition to posing a threat to human health, these metals can poison plants, livestock, and wildlife. Deciphering how metals are absorbed, transported, and incorporated as protein cofactors may help solve both of these problems. For example, edible plants could be engineered to serve as better dietary sources of metal nutrients, and other plant species could be tailored to remove metal ions from contaminated soils. We report here the …

Sec35p, A Novel Peripheral Membrane Protein, Is Required For Er To Golgi Vesicle Docking, Susan M. Vanrheenen, Xiaochun Cao, Vladimir V. Lupashin, Charles Barlowe, M. Gerard Waters

Dartmouth Scholarship

SEC35 was identified in a novel screen for temperature-sensitive mutants in the secretory pathway of the yeast Saccharomyces cerevisiae (Wuestehube et al., 1996. Genetics. 142:393–406). At the restrictive temperature, the sec35-1 strain exhibits a transport block between the ER and the Golgi apparatus and accumulates numerous vesicles. SEC35 encodes a novel cytosolic protein of 32 kD, peripherally associated with membranes. The temperature-sensitive phenotype of sec35-1 is efficiently suppressed by YPT1, which encodes the rab-like GTPase required early in the secretory pathway, or by SLY1-20, which encodes a dominant form of the ER to Golgi target …

Ecosystem Responses To Internal And Watershed Organic Matter Loading: Consequences For Hypoxia In The Eutrophying Neuse River Estuary, North Carolina, Usa, Hans W. Paerl, James L. Pinckney, John M. Fear, Benjamin L. Peierls

Faculty Publications

The contrasting impacts of externally supplied (runoff) and internally generated (nutrient stimulated phytoplankton blooms) organic matter on oxygen (0₂) depletion were examined and evaluated in the eutrophic, salinity-stratified Neuse River Estuary, North Carolina, USA. This nitrogen (N)- limited estuary is experiencing increasing anthropogenic N loading from expanding urban, agricultural and industrial development in its watershed. Resultant algal blooms, which provided organic matter loads capable of causing extensive low 0₂ (hypoxic) and depleted 0₂ (anoxic) conditions, have induced widespread mortality of resident fin- and shellfish. Phytoplankton blooms followed periods of elevated N loading, except during extremely high …

Shrimp Aquaculture: An Analysis Of Its Evolution And Organization; And The Development Of A Shrimp Growth Model, Adam Rana

Honors Theses

This paper examines the impetus for the development and subsequent rise of the shrimp aquaculture industry and continues by exploring a model that seeks to improve shrimp farmers' harvests by identifying specific variables affecting shrimp growth. Evidence reviewed from 1980 through today suggest that technological advancements, reduced prices, and increases in both the supply and demand for shrimp are positively associated with the industry's rapid ascent. The introduction of vertically integrated shrimp farms along with the ability for shrimp farmers to differentiate their products are also correlated with the industry's growth. Variables affecting shrimp growth were also studied to determine …

Invasion Genetics Of The Mediterranean Fruit Fly: Variation In Multiple Nuclear Introns, F. X. Villablanca, G. K. Roderick, S. R. Palumbi

Biological Sciences

Biological invasions generally start from low initial population sizes, leading to reduced genetic variation in nuclear and especially mitochondrial DNA. Consequently, genetic approaches for the study of invasion history and population structure are difficult. An extreme example is the Mediterranean fruit fly, Ceratitis capitata (Medfly), for which successive invasions during this century have resulted in a loss of 60% of ancestral genetic variation in isozymes and 75% of variation in mitochondrial DNA. Using Medflies as an example, we present a new approach to invasion genetics that measures DNA sequence variation within introns from multiple nuclear loci. These loci are so …

Phytotoxicity Of Pseudomonas Chlororaphis Strain O6: Role Of Phenazines And Implications For Biocontrol, Elizabeth Thomas

Biology

Phenazines, the water-soluble pigments produced naturally by bacteria with distinct antimicrobial properties, have been implicated in the biological control of several plant diseases. Pseudomonas chlororaphis strain O6, obtained from the rhizosphere of wheat, is known to produce at least three different phenazines, which include phenazine-1-carboxylic acid, 2-hydroxyphenazine-1-carboxylic acid, and 2-hydroxyphenazine. A field trial conducted in the fall of 1994 to test the biocontrol properties of O6 indicated that this strain inhibited wheat seed germination, which led me to hypothesize that phenazines cause phytotoxicity. Mutants of O6 created by Tn5 lux insertion (Phz^- mutants) that did not produce the pigments …

The Development Of A Bluetongue Virus Diagnostic Assay Using Heterologously Expressed Structural Protein Vp7 And Nonstructural Protein Ns2, Mary Anne Wise

Biology

The S1 gene of bluetongue virus that encodes major inner core protein, VP7, was cloned and expressed in the Thiofusion Expression Vector System. The VP7-thioredoxin protein was then partially purified. The nonstructural protein NS2 having previously been cloned into the GST Gene Fusion Vector System was also expressed and purified as NS2-GST fusion protein. These two viral proteins were used together in an immunologic detection assay. This assay was able to distinguish between bluetongue virus infected, vaccinated and noninfected sheep. Assayed serum samples of infected sheep, cattle, bison, and goats showed detectable antibodies to both VP7 and NS2, whereas vaccinated …

Improved Culture Of Tumor-Infiltrating Lymphocytes, Roger A. Burger

Biology

Adoptive immunotherapy using in vitro expanded tumor-infiltrating lymphocytes (TIL) continues to be the subject of research and clinical trials for the treatment of cancer. However, the culture methods used to expand large numbers of TIL are limited and often ineffective. In this study using murine TIL, the level of in vitro expansion, expression of adhesion molecules and infiltration into tumors after infusion was evaluated. A comparison was made between lymphocyte culture fluid (LCF), a bovine plasma-based medium, and a bovine serum-based medium (SCM) as the culture media. Because plasma-based media lack the lymphocyte inhibitory factors associated with serum-based media, it …

The Effects Of Pool Size On The Microinvertebrate Populations Of Chaney Lake, An Ephemeral Wetland Located In Bowling Green, Kentucky, Shannon Gaines

Mahurin Honors College Capstone Experience/Thesis Projects

Studies concerning the microinvertebrate communities of differing pool sizes were conducted at Chaney Lake, an ephemeral, karst wetland located in Bowling Green, Kentucky. As the lake begins to dry in the early summer, smaller, isolated ponds begin to form. Several ponds of various sizes were marked for analysis. Microinvertebrate samples and physiochemical readings were taken at each of the sites and were counted in the lab. T-tests were performed on the samples to determine if the microinvertebrate densities differed between ponds that dried later in the season as opposed to those that dried earlier. Ostracoda densities of the late dry …

The Reproductive Biology And Ecology Of Penstemon Harringtonii (Scrophulariacea): Implications For Conservation, Romaine L. Nielson

Biology

I examined the reproductive biology of Harrington's Penstemon, a rare endemic of the Colorado Plateau, to obtain information important to conservation efforts for this species. I applied four different hand-pollination treatments to P. harringtonii's flowers and found that it is partially self-compatible but sets more fruits when cross-pollinated by insects. Plant placement in new populations may be important because pollinators are more attracted to dense floral resources. Thus, the fruit set of plants within a 450 cm² area was compared with those at least 3 m apart. Unexpectedly, aggregated plants produced 16.1 fruits per plant compared to 21.0 …

Phylogenetic Characterization Of Endosymbionts In Psyllids (Hemiptera: Sternorrhyncha), Allen W. Spaulding

Biology

Most sternorrhynchan insects harbor endosymbiotic bacteria in specialized cells (bacteriocytes) near the gut, which provide essential nutrients for hosts. In lineages investigated so far with molecular methods (aphids, mealybugs, whiteflies), endosymbionts apparently have arisen from independent infections of common host ancestors and cospeciated with their hosts. Some endosymbionts also exhibit putatively negative genetic effects from their symbiotic association. In this study, the identity of endosymbionts in one major sternorrhynchan lineage, psyllids (Psylloidea), was investigated to determine their position in eubacterial phylogeny and relationship to other sternorrhynchan endosymbionts. Small-subunit ribosomal RNA genes (16S rDNA) from bacteria in three psyllid species (families …

The Reproductive Ecology, Demography, And Population Genetic Structure Of Arctomecon Californica Torrey & Fremont (Papaveraceae) In Fragmented And Unfragmented Habitat, Laura L. Hickerson

Biology

Arctomecon californica (the Las Vegas bearpoppy) is endemic to gypsum outcrops of the northern Mojave Desert. Native habitat of this plant in the Las Vegas Valley has been severely fragmented, while relatively undisturbed, unfragmented habitat still exists in the Lake Mead National Recreation Area. I studied the reproductive ecology and population genetic structure of this rare plant. Comparisons were then drawn between fragmented and unfragmented habitat. Arctomecon californica flowers are mostly self-incompatible, and require a pollen vector for successful seed production. Evidence of pollinator limitation was found in both habitat types, but plants in fragmented habitat were much less successful …

Velocity, Force, Power, And Ca2+ Sensitivity Of Fast And Slow Monkey Skeletal Muscle Fibers, Robert Fitts, Sue C. Bodine, Janell Romatowski, Jeffrey J. Widrick

Biological Sciences Faculty Research and Publications

In this study, we determined the contractile properties of single chemically skinned fibers prepared from the medial gastrocnemius (MG) and soleus (Sol) muscles of adult male rhesus monkeys and assessed the effects of the spaceflight living facility known as the experiment support primate facility (ESOP). Muscle biopsies were obtained 4 wk before and immediately after an 18-day ESOP sit, and fiber type was determined by immunohistochemical techniques. The MG slow type I fiber was significantly smaller than the MG type II, Sol type I, and Sol type II fibers. The ESOP sit caused a significant reduction in the diameter of …

Confocal Microscopy: A Powerful Tool For Biological Research, Amit Singh, K. P. Gopinathan

Biology Faculty Publications

Conventional light microscopy allows the observation of living as well as fixed cells and tissues to generate two-dimensional images. The out-of-focus information often obscures the ultrastructural details, especially in thick specimens with overlapping structures. The earliest available light microscopy visualized the objects in hydrated state in two-dimensions during their temporal development. The emergence of electron microscopy (EM) provided superb resolution of ultrastructural details, but it was applicable only for objects in the dehydrated state and thereby potentially introducing handling artifacts. The usefulness of optical methods, however, has been limited by the poor depth discrimination. Often, the fluorescence and reflectance images …

Changes In The Breeding Bird Community Of Subtropical Evergreen Forest In The Lower Rio Grande Valley Of Texas, 1970s-1990s, Timothy Brush, Alberto Cantu

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Breeding-bird censuses conducted in 1994-1996 at the Santa Ana National Wildlife, southern Texas were compared to those done on the same site in 1973-1978. The study site was described as subtropical evergreen forest in the 1970s, but is now thorn-forest with remnant evergreen forest. Canopy cover was incomplete and lower and trees were smaller and more densely packed in 1994-1996 than in 1973-1978. Seven bird species typical of thorn-forest and thorn-scrub, which were not present in 1973-1978, made up 20% of the breeding bird community in 1994-1996. Species tolerant of thorn-forest and thorn-scrub made up 76.0% of the breeding bird …

The Biology Of Xenopus By R. C. Tinsley And H. C. Kobel, Rafael O. De Sá

Biology Faculty Publications

The Biology of Xenopus presents a summary of current knowledge about a single genus resulting from a symposium held at the Zoological Society of London in September 1992. This approach to summarizing available information has also been taken for other taxa, such as Atelopus (Lotters, 1996). However, the task of compiling data for Xenopus is enormous relative to any other amphibian group, because Xenopus laevis has become a model system for molecular and development research (Cannatella and de Sa, 1993). Unfortunately, most of our knowledge of Xenopus is biased toward this single species. There are about 20 recognized species of …

Characterization Of The Prion Protein (Prp) Gene In Ten Breeds Of Sheep, A. R. Stephens, S. Wang, G. R. Holyoak, O. G. Timofeevskaia, T. L. Shay, W. Vernon, S. Ellis, J. Beever, Noelle E. Cockett

Undergraduate Honors Capstone Projects

Transmissible Spongiform Encephalopathies (TSE's) are neurodegenerative disorders characterized by a long generation time, spongy degeneration in the cerebral gray matter, neuronal loss and proliferation and hypertrophy of glial cells. An abnormal form of the prion protein (PrP) plays a major part in TSE pathogenesis and has been hypothesized to be the only component of the infectious agent. Some animals exposed to scrapie, the TSE affecting sheep and goats, seem to be resistant to development of the disease. Alleles encoding amino acid substitutions at codons 136 (A/V) and 171 (Q/R/H) have been associated with scrapie resistance. Other amino acid substitutions at …

Short-Eared Owl Post-Fledging Survival And Breeding Season Diet, Thomas A. Rivest

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

My research primarily focused on the survival of short-eared owls (Asio flammeus) from leaving the nest until their emigration from their natal territories during 1993 and 1994. I attached tarsal-mounted radio transmitters to nestlings prior to fledging. Of 25 fledgling short-eared owls monitored, 16 (64%) died prior to dispersal and one (4%) died after dispersing. Mammalian predation (5, 29.4%) was the primary cause of mortality followed by starvation (4, 23.5%), exposure (2, 11.8%), auto collision (1, 5.9%), burial (1, 5.9%), and unknown causes (4, 23.5%). Hatch date was found to be negatively correlated with fledgling survival.

A secondary …

Organic Compounds In Cyanea Capillata And Chrysaora Quinquecirrha, Kris Mitchell '98

Honors Projects

Cyanea capillata and Chrysaora quinquecirrha are two species of jellyfish which emit an "iodoform-like" odor. Attempts to identify the compound(s) which produce this odor have been made using chromatography techniques. Thus far, results obtained from column chromatography and GC-MS analysis have been inconclusive. However, these data suggest an hypothesis that may explain the origin of the odor. A low molecular-weight, highly volatile compound, such as ethylene, is a likely candidate for this elusive, odor-causing chemical.

Sustainable Development In The Third World: An Assessment Of The Conservation Actions In South Africa, Brazil, Malaysia, And Madagascar, Carol Rizkalla

Honors Theses

As a library research project, this thesis has gone beyond research in the library, and it could not have been possible without the aid of several people. First I must thank the organizations which responded to my request for information: the Center for Environmental Information, the Rainforest Action Network, the World Wildlife Fund, and Conservation International Specifically, Jill McLaughlin in the Communications Department of CI was· most gracious in sending me management plans for parks in Brazil and Madagascar. Carla Langeveld of the WWF, was very helpful during my visit to their library, and subsequently in my request for the …

The Effects Of Tactile/Kinesthetic Instructional Strategies In The Biology Classroom, Janice Batten Sees

Theses and Dissertations

The purpose of this study was to determine whether the addition of tactile/kinesthetic instruction to the biology classroom could significantly increase learning. Various kinds of tactile/kinesthetic lessons were taught to three experimental groups who also received visual and auditory instruction. These tactile/kinesthetic lessons included task cards, task puzzles, manipulatives, total body movement, and large floor games. The control group only received visual and auditory instruction. The subjects were 84 College Biology students from Buena Regional High School, a school in rural South Jersey. The classes varied in gender and race. The same instructor taught all classes and the length of …

Experimental Manipulation Of The Cost Of Thermal Acclimation In Drosophila Melanogaster, Robert A. Krebs, Martin E. Feder

Biological, Geological, and Environmental Faculty Publications

Acclimation to environmental change can impose costs on organisms. One potential cost is the energy and nutrients consumed by a physiological response, e.g. the resources required for expression of heat-shock proteins (Hsps). We examined the significance of this cost by genetic manipulation. We isolated four isofemale lines from a Drosophila melanogaster population previously transformed with a hsp70-kcZ fusion. Lines were similar in Hsp70 expression but differed in P-galactosidase expression upon heat shock, and replicates of each line were reared on a high quantity and low quantity medium. Multiple heat shock reduced survival in all lines, but did not increase developmental …

The Age Of The Kirkdale Cave Palaeofauna, Donald A. Mcfarlane, Derek C. Ford

WM Keck Science Faculty Papers

The Kirkdale Cave palaeofauna represents the original and classic 'warm', interglacial mammalian cave deposit in Britain. Although long considered to be 'Ipswichian' in age, no previous attempts to obtain radiometric dates have been recorded. Here we report a uranium-series disequilibrium date of 121,000 ± 4000 yr BP on a flowstone capping that overlay the original bone bed. The precision of the date exceeds that obtained at any other British Interglacial cave site, and permits tentative correlation with the high precision ice core records now available.

Energy Absorption During Running By Leg Muscles In A Cockroach, Robert J. Full, Darrell R. Stokes, Anna N. Ahn, Robert K. Josephson

All HMC Faculty Publications and Research

Biologists have traditionally focused on a muscle's ability to generate power. By determining muscle length, strain and activation pattern in the cockroach Blaberus discoidalis, we discovered leg extensor muscles that operate as active dampers that only absorb energy during running. Data from running animals were compared with measurements of force and power production of isolated muscles studied over a range of stimulus conditions and muscle length changes. We studied the trochanter-femoral extensor muscles 137 and 179, homologous leg muscles of the mesothoracic and metathoracic legs, respectively. Because each of these muscles is innervated by a single excitatory motor axon, …

Staphylococcus Succi Nus Sp. Nov., Isolated From Dominican Amber, L. H. Lambert, T. Cox, K. Mitchell, R. A. Rosselló-Mora, C. Del Cueto, D. E. Dodge, P. Orkand, R. J. Cano

Biological Sciences

Two bacterial isolates, designated AMG-D1^Tand AMG-D2, were recovered from 25-35-million-year-old Dominican amber. AMG-D1^Tand AMG-D2 biochemically most closely resemble Staphylococcus xylosus; they differ physiologically from other staphylococci. Fatty acid analysis and comparisons with extensive databases were unable to show relatedness to any specific taxon. Moreover, AMG-D1^Tand AMG-D2 contain tuberculostearic acid and meso-diaminopimelic acid, characteristic of the G+C-rich coryneform bacteria, as opposed to L-lysine characteristic of staphylococci. AMG-D1^Tand AMG-D2 have a G+C ratio of 35 mol%. Phylogenetic analysis with the 16S rRNA gene indicated that AMG-D1^Tand AMG-D2 were most closely …

Summary Of Submissions To Fisheries Management Paper No 108 - Issues Affecting Western Australia's Inshore Crab Fishery, Cathy Campbell

Fisheries Management Papers

The summary of submissions is a record of comments offered in respect to the contet of Fisheries Management Paper No. 108 : Issues affecting Western Australia's inshore crab fishery (the Issues Paper) and submitted by groups or individuals who have an interest in inshore crab fishing activity in this State. Concerns of the respective parties included a percieved decline in recreational crab catches at specific locations; instances of conflict between commerical and recreational crabs fishers in Geographe Bay; concern for the types of gear used to take crabs; a substantial rise in the catch of crabs in the Cockburn Sound …

Breeding Birds At The Idaho National Engineering And Environmental Laboratory, 1985 - 1991, James R. Belthoff, Leon R. Powers, Timothy D. Reynolds

Biology Faculty Publications and Presentations

During the summers of 1985-1991, bird censuses were conducted along 13 permanent routes located at the 2315-km² Idaho National Engineering and Environmental laboratory (INEEL, formerly INEL) in southeastern Idaho. The objectives of the surveys were to (1) compare avifauna in and near facility complex sites with remote, relatively undisturbed habitats, (2) identify trends in populations of sagebrush-obligate species and other common shrug-steppe species, and (3) determine the presence, abundance, and population status of species of special concern. Five routes were official U.S. Geological Survey, Biological Resources Division 40.0-km Breeding Bird Survey (BBS) routes (formerly administered by the U.S. Fish …

Characterization Of Swinepox Virus Secretory Polypeptides, Takeshi Shimamura

Masters Theses

Swinepox virus (SPV) is the only known member of the genus Suispoxvirus. SPV causes a mild disease in swine characterized by slight fever, and weight loss, associated with lesions restricted to the skin. There have been few studies on SPV. Other poxviruses, such as vaccinia virus, have been well characterized and the biological activities of their secretory polypeptides have been analyzed. This study describes a major SPV secretory polypeptide with an apparent molecular mass of 35kDa. Poxvirus encoded polypeptides secreted during infection are known to exhibit immunomodulatory activities. The 35kDa SPV secretory polypeptide was tested.for its ability to inhibit …