Abstracts are listed alphabetically by
the last name of the first author listed.
Research
SympOSIUM
INTERMOLECULAR INTERACTIONS IN PHE-NYLHYDRAZONE
Trina M. Arola
and William H. Ojala (Advisor)
Department of Chemistry
We are working toward preparing new
crystalline materials by co-crystallizing molecules we have designated
“bridge-flipped isomers.” In these isomers, two major parts of the molecule are
joined by a bridge of atoms; changing the bridge orientation relates one isomer
to the other. We are currently examining phenylhydrazones, in which the
bridge-flipped isomerism is Ar–NH–N=CH–Ar’ vs. Ar–CH=N-NH–Ar’ (where Ar =
aryl). Co-crystallization would be facilitated if the bridge-flipped isomers
were isostructural (same molecular packing arrangement). We are determining the
solid-state structures of phenylhydrazones by single-crystal X-ray diffraction
to identify isostructural bridge-flipped isomeric pairs for future
co-crystallization experiments. Intermolecular interactions linking molecules
into similar chains in the two solid isomers might encourage their
isostructuralism, so we have prepared phenylhydrazones substituted with halogen
atoms and nitrile groups to encourage intermolecular Lewis acid–Lewis base
interactions. We find H-bonding between the bridge N–H and the nitrile group to
be a competing and differentiating interaction.
INTERGENERIC HYBRIDIZATION BETWEEN THE SAND DOLLARS Encope
michelini AND Mellita isometra (ECHINODERMATA: ECHINOIDEA: MELLITIDAE)
Department of Biology
Hybridization may be viewed as
an obstacle to speciation and evolution or as a source of creative recom-bination
leading to positive adaptations. This research presents a case study of a
possible intergeneric hybridi-zation event between two groups of echinoids on
the
In 2004, research at the National Museum of Natural
History was conducted to investigate the origin of these sand dollars. Various
morphological characteristics of specimens of the presumed hybrids were
compared with those of the presumed parent taxa, Mellita isometra and Encope
michelini. Statistical analysis was not poss-ible due to the small sample
sizes; however, this study provides a broad analysis of many characteristics.
In some characteristics the hybrids fell directly within the broad limits of
variation of the proposed parents. In other cases, the presumed hybrids seemed
to be quite distinct, falling outside the range of variation of the presumed
parent taxa. Further study is required, including additional breeding
experiments, DNA analysis, and additional morphometric data sampling, including
examination of the plate structure and analysis of the internal skeleton.
WETLAND POND MACROINVERTEBRATE COMM-UNITIES ON THE ST.
OLAF CAMPUS
H. L. A. Austin and M. C. S.
Swift (Advisor)
Department of Biology
Aquatic macroinvertebrates
are invertebrates that are visible to the naked eye which live in both pond and
stream habitats. The purpose of this study was to learn to identify
macroinvertebrates, and to compile a reference macroinvertebrate profile for
ten ponds located on
EVIDENCE OF
DEPOSITION OF COMMERCIAL FERTILIZER IN AN UNPLOWED FLOODPLAIN PRAIRIE REMNANT
Elizabeth Bach and Marty Condon (Advisor)
Department of
Biology
Do unplowed areas of
remnant tallgrass prairie offer the best examples of unaltered or
"natural" prairie systems? Remnants that are on floodplains may show
evidence of human alteration even though the area has never been plowed or
intentionally altered. My project investigated the soil under Wearin Prairie, a
floodplain remnant, for evidence of alteration indirectly caused by human
actions. Specifically, my experiments were design-ned to test for the presence
of available phosphorus, a component of commercial fertilizer which might be de-posited
during flooding events. The results showed a correlation between the
concentration of available pho-sphorus and proximity of the sample site to the
MODERATION OF HUMAN RIBONUCLEASE INHIBITOR OXIDATION
SENSITIVITY BY SITE-DIRECTED MUTAGENESIS
Johann S. Bergholz, Barbara A
Hirschman, Sarah B. Miller, and Kimberly A. Dickson (Advisor)
Department of Biology
Human ribonuclease inhibitor
(RI) is a cytosolic protein critical for protecting cells from RNA degradation
by ribonucleases. With a femtomolar affinity, the binding of RI with
pancreatic-type ribonucleases is one of the strongest protein interactions
observed in nature. RI is built from highly conserved, alternating A and B
leucine-rich repeats (LRRs), each of which contains an α-helix and
β-sheet. Reduced cysteine residues contained in these repeats are critical
to protein structure but quickly oxidize under extracellular conditions,
complicating efforts to utilize RI as a laboratory reagent. Using site-directed
mutagenesis, we will mutate two highly conserved cys-teine residues at
positions 10 and 17 of the A-repeats in an effort to increase the stability of
RI. In order to main-tain molecular interactions within the tertiary structure
of RI position A10 will be replaced with a serine residue, while valine will be
substituted for the cysteine residue in position A17. Mutated proteins will be
isolated and puri-fied to ensure that structure and function have been main-tained.
PERTURBATION
OF AUXIN-MEDIATED TRAN-SCRIPTION VIA SYNTHESIS OF MOLECULAR INHIBITORS
Johann S. Bergholz, Sarah B. Miller, Ronald G.
Brisbois (Advisor), and Paul J. Overvoorde (Advisor)
Department of
Biology
Auxin, commonly
exemplified by indole-3-acetic acid (IAA), is known to play a role in plant
growth and development by affecting gene expression. The Aux/IAA family of
genes encodes short-lived nuclear proteins that can be induced within five
minutes to one hour upon exposure to IAA. The molecular mechanisms of auxin-mediated
gene expression, however, are not completely understood. Current research
points to the activation of auxin-response genes by directing proteolysis of
the Aux/ IAA family of proteins by the ubiquitin protein ligase SCFTIR1,
resulting in the activation of auxin response factors (ARFs), a known set of
transcription factors that would then arbitrate auxin-mediated gene expression.
Compound A, a furylacrylate ester of a thiadiazole hetero-cycle, has been shown
to inhibit auxin-mediated tran-scription, but neither the mechanism of action
nor the active part of this molecule are known. In this study we synthesized
different analogues of compound A to deci-pher the active core moiety of the
compound by GUS and qPCR analyses. With these results at hand, we will be able
to identify the target for compound A and gain a better understanding of auxin
functioning at the molecular level.
CREATION OF AN OXIDATION-RESISTANT RIBONUCLEASE
INHIBITOR
Owen Brafford, Catlin
Shortridge, and Kimberly A. Dickson (Advisor)
Department of Biology
Human Ribonuclease Inhibitor (RI) is a leucine-rich
repeat, horseshoe-shaped protein that binds to pan-creatic-type ribonucleases
to inhibit the degradation of RNA. The tertiary structure of RI is
characterized by repeating structural elements called A and B units. Each of
these units contains an α-helix and a β-sheet. RI contains 32
cysteine residues that create oxidative instability in the protein. Our goal
was to replace the cysteine residues with amino acids that would conserve the
structure of the protein without compromising its function. We replaced two A21
and five B21 cysteine residues with serine residues. Post-mutagenesis, the
mutant RI proteins were characterized for function and binding activity.
Possible benefits of an oxidation-insensitive RI would be as a useful
laboratory reagent and as a new tool for exploring and modulating interactions
with pancreatic-type ribonucleases.
MATE CHOICE MEDIATED BY SIZE AND CHEM-ICAL DEFENSE IN Nyssodesmus
python (POLYDES-MIDA: PLATYRHACIDAE)
Mercedes Burns and Mark A.
Davis (Advisor)
Department of Biology
Large mates are preferred in a variety of species,
presumably because larger size typically confers greater fitness. In chemically
protected species, mates may prefer more toxic partners for the same reason.
The common for-est millipede Nyssodesmus
python displays sexual dimor-phism in
body size and also produces a defensive com-pound containing hydrogen cyanide,
making it an organ-ism well suited to an experiment on mate preferences
highlighting both size and presence of defense compounds.
In research conducted as part of a study abroad course
with the CIEE Monteverde,
MICROWAVE SYNTHESIS OF IONIC LIQUIDS IN ORGANIC
CHEMISTRY LABORATORY
Nathan Burrows and David
Blackburn (Advisor)
Department of Natural Sciences
The topics of microwave synthesis, ionic liquids,
green chemistry, and neat (solventless) reactions are seldom taught in the
undergraduate laboratory setting. This lab provides a method to introduce and
experience all of these topics in a simple and easily available method.
Students produce butylmethylimidazolium bromide, a hydrophilic low-melting
ionic liquid, using a household microwave and a simple equipment setup using
common lab glassware. Students can then perform an ion exchange producing
butylmethylimidazolium hexafluorophosphate, a hydrophobic room-temperature
ionic liquid, as a liquid precipitate. Two of the 12 principles of green
chemistry, prevention of waste and atom economy, are exercised in this lab
through a neat reaction and purification method.
TURN
STRUCTURES OF A MODEL PEPTIDE SYSTEM: INSIGHTS FROM CIRCULAR DICHR-OISM
Sara J. Bush,
Kristine L. Carlson, and Kathryn A. Thomasson
Department of Chemistry
Cyclo(Gly-L-Pro-L-Pro)2 (cGPP2) is a
peptide model for cis and torsionally strained peptide bonds that exhibits a
strong distinctive UV circular dichroic (CD) spectrum. Circular dichroic
spectra were computed for the amide pi-pi* transition using the dipole
interaction model for various conformations of the peptide. Conformations of
cGPP2 were created initially from crystal and NMR data, and followed by energy
minimizations via molecular mechanics using three force fields: CVFF, CFF91,
and AMBER. A series of dielectric constants, representing various solvent
conditions from gas (0) to water (78.5), were used for the minimizations. The
minimized struc-tures were examined for structural features such as beta- and
gamma-turns. The CD spectra for each conformation were calculated using a
variety of parameters, and each result was compared with the published
experimental spectrum in acetonitrile.
STRESS FIBER FORMATION IS ESSENTIAL FOR
CELLULAR MIGRATION IN CHINESE HAMSTER LUNG FIBROBLASTS
Jenny L. Canine,
Joseph J. Provost (Advisor), and Mark A. Wallert (Advisor)
Department of Biosciences
The coordinated reorganization of the
actin cytoskeleton is a common cellular event. In a variety of cell types
including lymphocytes, the formation of stress fibers is indicative of a
stabilized attachment state where the cells no longer migrate. The research
presented here demonstrates that stress fiber formation is essential for
cellular migration in CCL39 cells, Chinese Hamster Lung fibroblasts. As in
virtually all other mammalian cells, the Sodium–Hydrogen Exchanger (NHE) is
present and plays a dual role in pH regulation and cytoskeletal attachment to
the plasma membrane. In this second role, NHE is also essential for the
formation of stress fibers in cells. Previous research from our laboratory has
shown that phenylephrine (PE) stimulates NHE and induces stress fiber formation
in these cells. To investigate the role of stress fiber formation, CCL39 cells
were allowed to grow into a confluent monolayer in a 35 mm culture dish. The
cells were then serum deprived 12 to 18 hours. At this point the monolayer was
wounded using a standard cell scraper. The cells were then allowed to migrate
into the wounded area for 24 hours in one of four conditions: serum-free media,
serum-free media with PE, 10% serum media, and 10% serum media with PE. Our
data show that in PE-stimulated CCL39 cells, stress fibers are present in the
cell immediately adjacent to the wound area and in cells that have migrated
into the wound. These studies indicate that stress fiber formation has a direct
involvement in cell migration.
STRUCTURAL INSIGHT FROM
CIRCULAR DICHROISM
Kristine
L. Carlson, Mark R. Hoffmann, and Kathryn A. Thomasson
Department of Chemistry
The tricyclic structure
of the substituted diketo-piperazine cyclo(L-Pro-L-Pro) constrains its possible
geo-metric conformations to three minimum energy structures. The relationship
of these three structures was examined via comparison of UV circular dichroic
spectra calculated using the classical dipole interaction model with experi-mental
CD (Bowman, R. L.; Kellerman, M.; Johnson, W. C., Jr. Biopolymers 1983, 22, 1045). Starting with crystal structure data for the platter
conformation, the three conformations were obtained by geometric optimization
using MP2, DFT, and three molecular mechanics force fields. The pi-pi* spectrum
produced by each conform-ation was distinct but followed a pattern with a
negative band at ~ 185 nm and a positive band at ~ 210 nm.
The CFF91 force field
was the only classical force field to produce structures whose composite CD
resembled experiment, but conformations were not clearly defined by CD due to
the high (~ 20 degrees) amide bond torsion angles. Inclusion of water as
solvent in the class-ical optimizations through the use of a dielectric
constant resulted in very small changes in geometry for each con-formation and
little or no shift in weighted CD, although the energies obtained using the
CFF91 force field permit-ted real occupation of the chair and boat
conformations (18% and 31%, respectively). DFT and MP2 energy calc-ulations
indicated that the population of the molecule in the three conformations is
roughly equal (MP2: 34% platter, 33% chair, 33% boat). Boltzmann-weighted
composite CD supported this conclusion through accurate description of the two
pi-pi* peaks with respect to one another.
SOY PROTEIN ISOLATE
Michelle Caron
and Gina Mancini-Samuelson (Advisor)
Department of Chemistry
The purpose of this project is to develop
a case study for the Advanced Analytical class that focuses on the High
Performance Liquid Chromatography instrument. The project focuses on the
isolation of Soy Protein Isolate, 11S, and 7S protein from soy flour and
other soy products.
MOLECULAR ANALYSIS OF A TRANSCRIP-TIONAL SILENCER IN Drosophila melanogaster
Chris Chamberlain and Presley
Martin (Advisor)
The MM-50 transgenic line of Drosophila melanogaster contains a D. melanogaster Alcohol dehydrogenase (Adh) transgene inserted at
position 25C of chromosome 2. Previous analysis has shown that expression of
this Adh transgene is inhibited by a silencing activity located in an 1180 b.p.
region near the 51 end of the inserted gene. The sequence of the
silencer region revealed the existence of two 20 b.p. homologies, which have
been shown to inhibit Adh expression by 50%. The objective of this
investigation was to determine what other sequences within the silencing region
are required to produce the near 100% inhibition of expression observed when
the whole region is present. Seven unique fragments of the silencer sequence
were cloned using PCR and purified using standard procedures. Two fragments
contain the first homology of the sequence, one fragment contains the second
homology, and four fragments contain neither of the homologies. Each of the
seven fragments were transformed into plasmids containing a functional Adh
gene, thus yielding seven complete plasmids, each containing one of the
fragments and one copy of the Adh gene. Each plasmid will be injected into Drosophila embryos and the larvae will
be assayed for the level of Adh gene expression.
THE EFFECTS OF OPIOID ANTAGONIST NAL-TREXONE IN
ANIMALS MOTIVATED TO EAT BY TASTE
Munya Chimukangara and Tim
Shaw (Advisor)
Department of Biological Sciences
It is well known that the opioid system plays a
significant role in the regulation of palatable food intake. Generally
speaking, opioid agonists increase feeding while opioid antagonists decrease
feeding in non-food-restricted animals. These drugs, however, have a substan-tially
reduced effect in food-deprived animals. These data are based predominantly on
studies performed on the peripheral opioid system. Not much is known about the
effects of these drugs when administered into the opioid receptors of the
central nervous system. However there are data suggesting that food intake
regulation is also dependent on brain sites in the hypothalamus. The hypo-thalamus
is known to have nuclei associated with energy-and-reward-related feeding. In
this study I was therefore trying to find out if the administration of
Naltrexone in the hypothalamic paraventricular nucleus (PVN) would decrease
food intake more effectively in a food-restricted (energy needs-related) model
than in a non-food-restricted (reward-related) model. My results suggest that
Naltrex-one more effectively decreases intake of food in the food-restricted
model than in the non-food-restricted model. The data also suggest that the PVN
is primarily involved in energy-needs-driven-food intake in comparison with
reward-driven food intake.
ANALYSIS OF
THE EXTRACELLULAR HEMO-GLOBIN FROM Lumbriculus variegatus
Jessica Curtis, Rebecca Derby, Melissa Seefeld, Lee
Vang, and Kay Tweeten (Advisor)
Department of
Biology
The major carrier of
oxygen in the
The hemoglobin was
isolated from homogenates of worm tissue by ultracentrifugation and size
exclusion chromatography. The morphology, subunit composition, and size of the
hemoglobin were determined by electron microscopy and showed that the structure
consisted of two hexagonal-shaped rings that were 265 Å in width and composed
of six subunits each. Western blot analysis showed that antibodies against
human hemoglobin bound to four of the proteins with molecular weights of
14,900, 15,300, 16,100, and 16,500 daltons, suggesting these are the
oxygen-binding proteins. Five to six potential linker proteins with molecular
weights ranging from 26,200 to 36,000 daltons were also observed. The
glycoprotein composition of L. variegatus hemoglobin appeared to be
more complex than that of earthworm hemoglobin with all four oxygen-binding
proteins and the predominant linker protein being glycosylated. Hemoglobins
from L. variegatus and Lumbricus terrestris were compared by
two-dimensional gel electrophoresis to further evaluate the similarities and
differences in the proteins composing these assemblages.
THE GENDER GAP IN EARNINGS: DOES URBAN LOCATION
MATTER?
Amanda Demeules and Marsha
Blumenthal (Advisor)
Department of Economics
Dating back to ancient
times one can find references and data pointing to women not earning as much as
men. In fact Leviticus (27: 3–4) states that a woman is worth 30 shekels of
silver and a man 50 shekels of silver. This paper aims to explore the modern
gender gap in earnings in midwestern
states, specifically, examining the influence of metropolitan location.
Individual data from the Current
Population Survey will be used to construct an
PROJECTIONS OF RVM NEURONS TO PAIN-RELAY SITES
David H. Do and Martin W.
Wessendorf (Advisor)
Department of Neuroscience
Pain, which warns the body of potentially harmful
stimuli, could hinder one’s ability to act protectively in dangerous
situations. It is speculated that, during a “fight or flight” response, neurons
in the rostral ventromedial medulla (RVM) of the brainstem send inhibitory
signals down the spinal cord to block trans-mission of pain. Activation of m-opioid receptors in the RVM by drugs such as morphine
and heroin utilize these pathways to regulate pain in much the same ways. In
contrast, in the case of neuropathic pain, RVM cells appear to work in an
excitatory manner to enhance nociception. These phenomena are well documented,
but the mechanisms by which they occur are less understood.
The RVM is populated by cholinergic (ChAT) and
serotonergic (5-HT) neurons, among others. These neurons, which signal via the
neurotransmitters acetyl-choline and serotonin, respectively, may play a key
role in pain facilitation by preventing or amplifying signals relayed by
neurons in the spinal cord. In this experiment, the potential role of these RVM
neurons in pain modula-tion was examined by finding neural connections to the
dorsal horn and the spinal trigeminal nucleus, two regions of the nervous
system where peripheral sensory information is integrated.
GENETIC SCREEN OF
SECRETION MUTANTS IN Chlamydomonas
Dina
Dobraca, Milkeesso Foge, Srividya
Gainedi, Sarah Merkel, Paul Sarjo, and
Anton Sanderfoot (Advisor)
Department of Plant
Biology
Secretion is an
essential activity that plays important roles in numerous cell functions, such
as cell-to-cell communication, waste disposal, and cell defense. The purpose of
this project is to characterize previously unidentified genes involved in
secretion in the model organism Chlamydomonas
reinhardtii, a unicellular haploid green alga. We expect that Chlamydomonas will be a useful model
organism for characterizing secretion mutants because only one gene copy of the
haploid organism needs to be mutated for the strain to have a mutant phenotype
and the unicellular plant may survive with defects that may be lethal in
complex, multicellular plants.
Using a forward genetic
approach, a collection of mutant strains will be screened for secretion defects
using an endogenous secreted enzyme as a primary screen. A secondary screen
will use a synthetic, secreted green fluorescent protein (GFP) construct to
confirm secretion defects and to determine the location of the blocked
secretion product. Briefly, wild-type Chlamydomonas
will secrete the GFP extracellularly; in a mutant with a secretion blockage,
the GFP will accumulate inside the cell at the point of blockage. We are at the
stage of creating and confirming the expression of the fluorescent protein
constructs. In the future, we hope to use these tools to identify plant-specific
secretion genes in Chlamydomonas and
apply these results to multicellular crop plants.
Readability
Levels of High School and College Chemistry Textbooks
Elizabeth A.
Drommerhausen and Dr. Jeffrey R. Pribyl (Advisor)
Department of Chemistry and Geology
In many science classes the textbook is
frequently the determining factor for the content of a course. This is
particularly the case where chemistry education is concerned. Just how
effective is that heavy, expensive tool? While textbook content is critical,
another factor just as critical is often overlooked. That factor is the reading
level, also known as the readability level. Chemistry textbooks typically are
written at a reading level that is well above secondary students’ or college
students’ abilities. Numerous high school and college chemistry textbooks were
analyzed for their readability level using the Fry and Raygor readability
graphs. The results of this work confirm that the readability level of
chemistry textbooks is often times well above the reading level of the target
audience.
THE INVISIBLE HAND OF NATURAL SELEC-TION: SMITH,
John Dukich and Mark Borrello
(Advisor)
Department of Ecology, Evolution and Behavior
Although Adam Smith published The Wealth of Nations in 1776 and Charles Darwin published The Origin of Species in 1858 their
ideas have had a profound impact on modern thought. How have these two ideas,
in the context of eighteenth- and nineteenth-century thought, helped to create
the global gap between the wealthy and the poor? Smith and Darwin, as well as
other thinkers of their time, were influenced by contemporary society and
ideas. These ideas, of reductionism, mechanism, and scientific materialism,
have been inherited by modern science and modern societies, which in turn have
shaped how humanity perceives itself and what’s expected of itself. After
putting Smith and Darwin in historical con-text, I argue that such a wide gap
between the wealthy and the poor has arisen, in part, due to misinterpretations
of their respective works as well as due to the inherited ideas of the past 300
to 400 years. I conclude with what is necessary to overcome these obstacles and
the implications this would have.
ERK ACTIVATION BY PHOSPHOLIPASE D THROUGH
THE α-1 ADRENERGIC RECEPTOR IS Ras DEPENDENT
Matthew P. Duval,
Joseph J. Provost (Advisor), and Mark A. Wallert (Advisor)
Biosciences Department
Phospholipase D (PLD) is considered an
important signaling molecule in many growth factor pathways. PLD converts
phosphatidylcholine into choline and phosphatidic acid (PA). The PA generated
by PLD is thought to recruit Raf to the lipid rafts of cell membranes, leading
to stimulation of growth factor signaling com-plexes. Previous experiments in
our laboratory have shown the addition of primary butanol inhibits ERK
activation by blocking PA production. While this work suggests that PLD is
involved in the activation of the ERK signaling pathway, it does not explain
its mech-anism. To investigate the role of PLD in ERK activation, two
short-chain, cell-permeable phosphatidic acids
(1,2-Dihexanoyl-sn-Glycero-3-Phosphate and 1,2-Dilauroyl-sn-Glycero-3-Phosphate)
were incubated at several times and concentrations with CCL39 fibroblasts. Both
short chain phosphatidic acids (scPA) act as endogenously added PLD product.
Both the 6 and 12 acyl scPA stim-ulated ERK activation in a dose- and time-dependent
manner with maximum ERK activation observed with the 6 acyl scPA. Ras
activation pull down assays conducted with phenylephrine (PE) stimulating cells
showed Ras activation. When a primary butanol was added prior to stimulation,
PE did not activate Ras. Additional evidence for a Ras-dependent PLD-ERK
activation was determined through dominant negative Ras (D/N Ras). Expression
of D/N Ras blocked activation of ERK by PE. The ability of D/N Ras to inhibit
PA activation of ERK was also invest-igated. This is a novel mechanism for PLD
involvement in growth factor pathways. This work was supported by a grant from
the NIH, Award number 1 R15 HL074924-01A1.
SEQUENCE AND EXPRESSION OF THE FGF-10 GENE IN Xenopus
laevis LUNG DEVELOPMENT
Brett D. Einerson and Brian
Hyatt (Advisor)
Department of Biological Sciences
During lung bud morphogenesis, reciprocal interactions
between the epithelial endoderm and the mesenchyme surrounding it lead to early
branching of the pulmonary system. Members of the fibroblast growth factor
(FGF) family, along with their receptors, have been shown to play an integral
part in mediating these inter-actions. FGF-10 specifically has been shown to be
an essential regulator in lung formation. The FGF-10 gene was isolated from Xenopus laevis, and its expression
during lung development was examined. X.
laevis serves as an effective model organism for this study. Gathering
information about gene expression in this organism expands our understanding of
pulmonary development.
ANALYZE THIS! A CASE STUDY APPROACH IN THE
ANALYTICAL CHEMISTRY LABORATORY
Sarah Evans, Gina
Mancini-Samuelson (Advisor)
Department of Chemistry
If one contemplates art and science for a minute,
artists are really quite similar to chemists.
Both are personally engaged in combining, transforming, and
experimenting with materials. In my
personal opinion, the relation of art to chemistry is, in fact, the most overt
among all the scientific disciplines.
This research project incorporates art with chemistry creating that
unforeseen bond. In this project, a case
study was created for the use in Advanced Analytical Chemistry course at the
A SPECTRAL ANALYSIS TEST OF THE FEMALE MIMICRY
HYPOTHESIS OF DELAYED PLUM-AGE MATURATION
Ben
Freeman and Mark A. Davis (Advisor)
Department of Biology
Delayed plumage maturation (DPM) in birds is the
retention of subadult plumages by individuals of one sex when sexually mature.
The female mimicry hypo-thesis of DPM suggests that subadult males are selected
to mimic females in appearance, as has been demonstrated in animals from
insects to lizards, and in adult males of one bird species (Langmore et. al.
1999). Additionally, the female mimicry hypothesis has been suggested to apply
more widely to birds with DPM and female-like subadult plumages. A
full-spectrum analysis of two bird species with the above characteristics,
painted buntings (Passerina ciris) and American redstarts (Setophaga
ruticilla), revealed at least one distinguishing plumage patch in P.
ciris and none in S. ruticilla. The distin-guishing plumage patch in
P. ciris was the lower back, which could be a concealable badge.
Thus, the female mimicry hypothesis could, at least from this spectral
perspective, apply to both species.
THE ROLE OF 5-HYDROXYTRYPTAMINE (5-HT) AND
THE 5-HT1A RECEPTOR IN HUMAN T CELL PROLIFERATION
Audrey Geiger,
Melinda Hexum, Kate Ruter, and Dr. Jodi Goldberg (Advisor)
Biology Department
Previous research has shown that the
neurotransmitter serotonin, or 5HT, is necessary for T cell proliferation.
However, these studies have employed heterogeneous culture systems. In
order to determine the specific impact of 5-HT on human T cell proliferation, T
cells were first purified from whole blood to greater than 98% purity. T cells
were then labeled with a fluorescent dye and active-ted in one of two manners.
T cells were activated in the absence of other cells by incubating purified T
cells with anti-CD3/anti-CD28 coated beads (accessory cell inde-pendent
activation). Alternately, T cells were activated in the presence of
accessory cells and the T cell mitogen phytohemagglutinin (PHA), a plant lectin
(accessory cell dependent activation). The role of 5-HT in this
activation was assessed by either adding the 5-HT synthesis inhi-bitor pCPA or
by adding 5-HT receptor antagonists to the cultures. Flow cytometry was
used to measure T cell proliferation as a decrease in T cell associated fluor-escence.
Inhibition of proliferation by pCPA was observ-ed at a lower concentration in
accessory cell dependent cultures than in accessory cell independent cultures.
Inhibition by Methiothepin, a general 5-HT receptor antagonist, was observed in
cells stimulated by both accessory cell dependent and accessory cell
independent methods at equal concentration. No inhibition by Nan-190, a
specific 5-HT1A receptor antagonist, was observ-ed. Reversal of inhibition of T
cell proliferation in these cultures by the introduction of 5HT into the cell
cultures has not yet been achieved.
STRUCTURAL STUDY OF ALPHA-AMYLASE:
SELECTION OF SCAFFOLDING STRUCTURES AND DOMAIN SWAPPING
Robyn Gilbertson
and Paul Tavernier (Advisor)
Department of Chemistry
The structure of Bacillus licheniformis alpha-amylase was studied by viewing its pbd
file 1BLI with Rasmol. The 11th alpha-helix was selected for use in
this project. Similar sequence helices were found using online bioinformatics
databases such as Conserved Domain Database and Protein Data Bank. An
alpha-helix in hydro-lase from Pseudomonas
stutzeri was selected for the domain swap. Stratagene's QuikChange II
Site-Directed Mutagenesis Kit was used to delete the 30-base-pair DNA sequence
coding for the selected alpha-helix from AmyE, the gene for alpha-amylase in B. licheni-formis. Plasmid pRL298
containing AmyE was the DNA template used for the mutagenesis. Using the
successful deletion plasmid, the DNA sequence for the P. stutzeri helix was inserted using the QuikChange Kit. Results
were verified by growth on LB agar plates containing kanamycin and starch and
by molecular weight deter-mined by gel electrophoresis.
AdS_2 SOLITON
DYNAMICS
Kassahun Haileyesus and Tonnis Ter
Veldhuis (Advisor)
Department of
Physics and Astronomy
The dynamics of a
soliton in a two-dimensional curved space-time is worked out. Transformation
rules in AdS_2 space are found and Maurer Carton one forms are used to
construct a Lagrangian that is invariant under AdS_2 transformations. This
Lagrangian is shown to be equivalent to the Lagrangian of a relativistic
Harmonic oscillator. Conserved quantities associated with symme-tries are found
using Noether's method and they are used to find solutions to the Euler
Lagrange equations of mo-tion. From the invariant action, the conjugate
momentum is determined and the Hamiltonian is constructed. This Hamiltonian is
then shown to be equivalent to that of a conformal mechanics in one dimension.
THE EFFECTS OF LIPOPHOSPHOGLYCAN STIMULATION ON
MACROPHAGE GENE EXPRESSION
Cassondra Halsted and Joyce
Doan (Advisor)
Department of Biology
Leishmania spp. are protozoan parasites which are transmitted by
sandflies or, to a lesser extent, by the sharing of needles. Leishmania parasites are found all over
the world, although infection with these organisms is much less common in the
EFFECTS OF
NEUROTENSIN ON THE SMOOTH MUSCLE TISSUE OF THE
MOUSE UTERUS
Nellie Hangge and Teresa
DeGolier (Advisor)
Department of Biology
Research has shown neurotensin (NT), a biolog-ically
active peptide, to produce various effects in mam-malian smooth muscle tissue.
NT inhibits rat intestine yet stimulates guinea pig colon. This study
investigated whether NT would have an effect on smooth muscle tissues of the
isolated mouse uterus. Oxytocin was used as a positive control for uterine
contraction. Uterine horns from mice in the diestrus stage of the cycle that
were suspended in the smooth muscle bath and subjected to higher doses of NT
(10-7-10-6M) increased contractile frequency. Oxytocin caused an increase in
strength of contraction within tissues from mice in estrus at these same doses.
These results suggest that NT may play a role in uterine contraction during
diestrus and, therefore, mouse reproduction.
DESIGN AND SYNTHESIS OF TRPV1 ANTAGON-ISTS:
PROBING THE D-REGION BINDING SITE USING AMIDOALKYL SUBSTITUENTS
Victoria D. Held
and David B. Rusterholz (Advisor)
Department of Chemistry
University of Wisconsin–River Falls,
TRPV1 (transient receptor potential
vanilloid subfamily 1) is a membrane-bound ion channel protein that mediates
the pain response elicited by capsaicin, resiniferatoxin, and similar
drugs. Structure activity studies of
compounds that bind to TRPV1 indicate several binding sites, namely: (1) an
aromatic “A” region, (2) a polar “B” region, and (3) a hydrophobic “C” region. Recently a fourth region has been proposed
based on the structure of resiniferatoxin. This fourth “D” region is thought to
be responsible for the high potency exhibited by resiniferatoxin. A new series
of potential TRPV1 antagonists was designed that incorporates molecular
features intended to interact with the known A, B, and C binding sites. In
order to investigate the interaction of the D binding region, amidoalkyl groups
were incorporated into the target structures. The synthesis of several of
members of the target series was accomplished using a convergent synthetic
strategy. Ultimately these compounds will be tested for their effectiveness as
TRPV1 antagonists.
THE EFFECTS
OF INHIBITION OF SEROTONIN SYNTHESIS ON T CELL PROLIFERATION
Melinda Hexum, Audrey Geiger, Katelyn Ruter, and Dr. Jodi Goldberg (Advisor)
Department of
Biology
Previous research has
indicated that serotonin (5-hydroxytryptamine, 5HT) is a signal necessary for
human T cell proliferation. The role of 5HT in T cell prolifer-ation was
investigated by examining the impact of p-chlorophenylalanine (pCPA), a
serotonin synthesis inhib-itor, on the proliferation of purified human
peripheral blood T cells activated by accessory cell independent (anti-CD3/CD28
beads) and accessory cell dependent (phytohemagglutinin, PHA) methods. T cell
proliferation in response to either method of activation was inhibited by pCPA,
though T cells activated by PHA and accessory cells were inhibited at
significantly lower doses than pure T cells activated with antibody-coated
beads. Inhibition of proliferation with
pCPA was most effective when added upon initiation of T cell activation, with
inhibitory effects progressively reduced when pCPA was added on day 1 or 2
after activation. Attempts were made to reverse the inhibitory effects of pCPA
on T cell proliferation by providing pCPA treated cells with exogenous 5HT or
5-hydroxytryptophan (5HTP), but neither restored prolifer-ation at any
concentration tested. These data suggest that T cells are inhibited by pCPA,
but that non-T cells may be more sensitive to pCPA’s effects. It remains to be
determined if the inhibition occurs via a serotonin-dependent pathway.
GAS CHROMATOGRAPHY DETECTION OF TERBUFOS
Cori Hollingsworth, Ian
MacRae, and Julie E. Larson (Advisor)
Department of Chemistry
Terbufos, an active ingredient in granular pesticide
(Counterâ-BASF), is applied to
cultivated soil in
SEX SELLS: THE ECONOMICS OF PROSTITU-TION
Anna C. Hovde and
Fahima Aziz (Advisor)
Department of Management and Economics
Prostitution is illegal in most countries
of the world, but the market for paid sexual services still flour-ishes. The
United Nations estimates that prostitution is a $7 billion-a-year industry.
Prostitution is openly adver-tised in many local newspapers, and street
prostitutes can be seen in major cities even where prostitution is illegal.
This study examines why the market for sexual services exists and the costs it
imposes on society. The supply and demand sides of the
EXPERIMENTAL INVESTIGATION OF AN ELEC-TROPHILIC
AROMATIC ADDITION REACTION
Michael Huehn and Jack Waas
(Advisor)
Department of
In 2005, Chi and coworkers reported an unusual
electrophilic aromatic addition reaction (AdEAr) (Choi, H. Y.;
Srisook, E.; Jang, K. S.; Chi, D. Y. J.
Org. Chem. 2005, 70, 1222-1226). The AdEAr
and electrophilic aromatic substitution (EAS) pathways share a common initial
mechanistic step. After one electrophilic aromatic bromination of the usual
variety, the addition of a second bromine is thought to proceed with further
addition of methanol rather than deprotonation. This addition of methoxy is
observed only under basic methanolic condi-tions, and requires either a
pyridine moiety or added pyridine. This is contrary to what is normally
observed under acidic or neutral conditions which result in EAS only. Our
initial results indicate that the report of the AdEAr occurs in the
manner reported by Chi and cowork-ers. These results are based on experiments
performed on naphthalene and quinoline derivatives. Chi and coworkers reported
their experimental results but did not report any computational results. Our
preliminary semi-empirical and DFT calculations compare reaction energies of AdEAr
with those of EAS. Our research will contribute to the advancement of organic
chemistry and have possible applications in pharmaceuticals.
SULFONATION
OF COMPLEX BIOMOLECULES BY THE BIOCATALYTIC TRANSFER OF SULFINYL DERIVATIVES
Tuere A. Hughes, (Romas J.
Kazlauskas), Christopher K. Savile, and Paul F. Mugford
Department of Biochemistry, Molecular Biology, and
Biophysics
Sulfate groups on
complex biomolecules in nature, such as hormones, sugars, and aminoglycans,
play a key role in their physiological function. These sulfate groups are
essential in hormone regulation, cellular degradation, blood coagulation, and
cell–cell recognition processes such as cell adhesion, developmental cell
signaling, bacterial and viral pathogenesis, and tumor metathesis. A major
barrier to determining the structure–function relationships of sulfate groups
in biology is the great difficulties in the chemical and biochemical syn-theses
of complex sulfonated biomolecules and analogs. Chemical methods cannot select
among the many groups with similar reactivity in a complex biomolecule, and
biosynthetic methods that mimic natural biosynthesis yield only trace amounts
of products. We propose to use unnatural reactions coupled with biocatalytic
methods to overcome these difficulties. The use of enzyme catalysis will
provide the advantage over chemical methods by showing selectivity for specific
groups. The use of unnatural reactions and conditions will allow for the
production of large amounts of desired products.
Our aim is to identify proteases and sulfinyl group donors for the
biocatalytic synthesis of complex biomolecules containing sulfates. Our
working hypothesis is that sulfinyl groups are similar enough in structure and
chemical reactivity to acyl groups, that proteases that normally transfer acyl
groups will also transfer sulfinyl groups. We propose
a two-step method involving an initial protease-catalyzed addition of a
sulfinyl group, followed by chemical oxidation to a sulfate. We synthe-sized
and tested the enzymatic hydrolysis of dibenzyl sulfite and diphenyl sulfite by
reacting with six proteases: subtilisin Carlsberg, subtilisin BL, pronase,
pepsin, alpha-chymotrypsin, and penicillin acylase.
ECOLOGICAL
GENOMICS: ANALYZING GENE-TIC DATA FROM Marchantia USING ISSRs AND THE CEQ 8000
Eun
Hyuk Chang, Linda Fuselier (Advisor), and Michelle Malott (Advisor)
Biosciences Department
Ecological genomics is an
emerging field at the interface of ecology, evolutionary biology, and genomics.
The application of genetic information such as genome structure, DNA sequence,
DNA variation, and gene function is helping researchers better understand the fundamental
mechanisms of evolutionary and developmental biology.
This, in turn, contributes to our understanding of
the ecology of a variety of organisms.
Most genomic applications
involve isolation of DNA, polymerase chain reaction (PCR) amplification of specific
regions of DNA, and the analysis of the resulting amplification products in a
manner relevant to the question being asked. For example, examining the DNA
sequence and determining the amount of genetic diversity of a population of
organisms can be helpful in addressing questions involving reproductive
behaviors, evolutionary changes, and overall health of the species.
Traditionally, analysis of amplification products is done by gel
electrophoresis and visual scoring of gels. This can be a time-laborious
process when attempting to analyze many samples (i.e., different individuals) from different sample sites or
locations in a statistically meaningful manner. This poster describes the use
of a new instrument, the CEQ 8000, at MSUM for examining the genetic diversity
of Marchantia species.
IS THERE A ROLE FOR Rap1 IN THE MAMMAL-IAN
CELL CYCLE?
Andrea Johnson
and Jennifer L. Cruise (Advisor)
Department of Biology
The small G-protein Rap1 has been linked to a number of
signaling pathways involved in the cell cycle, but its exact role is unknown.
Prior research demonstrating that endogenous Rap1 expression is down-regulated
prior to the onset of DNA synthesis has led to the hypothesis that Rap1
activity regulates the cell cycle. We are testing the predictions that
increasing active Rap1 in cells would decrease DNA synthesis and cell
proliferation, and decreasing active Rap1 would increase DNA synthesis and cell
proliferation, using mammalian MRC-5 (fibroblast) and MDCK (epithelial) cells.
These cells were transfected transiently or stably with either an activated
Rap1 gene, a control plasmid, or a dominant-negative Rap1 gene. The cell cycle
was then monitored through flow cytometry, BrdU labeling index assays, and cell
counts using a hemacytometer. Flow cytometry experiments and BrDU labeling
studies thus far have suggested that active Rap1 reduces baseline DNA synthesis
and response to growth factor stimulation. Dominant-negative Rap1 appears, at
least to some extent, to have the opposite effect, increasing baseline DNA
synthesis and response to growth factors. In addition, cell counts in MDCK
stable cell lines reveal a higher overall proliferation rate in cells
expressing dominant-negative Rap1, and a lower rate in cells expressing
increased active Rap1, when compared with controls. These preliminary data
support our hypothesis that Rap1 has a regulatory effect on the mammalian cell
cycle, but further, more specific experimentation is necessary to confirm our
results and identify the cell signaling components that may explain this
pattern of regulation.
THE ROLE OF OXIDATIVE STRESS IN MATER-NAL
mtDNA INHERITANCE
Frank L. Johnson
Jr. and Dr. Ellen Brisch (Advisor)
Department of Biosciences
The purpose of this investigation is to
determine if, and to what extent, oxidative stress plays a role in maternal
mtDNA inheritance. Upon fertilization, the paternal mitochondria are tagged
with ubiquitin and degraded by proteolytic enzymes; therefore the paternal
mtDNA is not incorporated into the zygote. Free radical oxygen (O2-)
is a known byproduct of oxidative phosphorylation and is also known to destroy
biological tissues by the mechanisms of oxidation. The methods employed in this
investigation are used to determine the extent of oxidative damage to paternal
mtDNA. This may offer evidence as to why paternal mtDNA is not inherited.
AN
EXAMINATION OF ROCK PHOSPHORY-LATION OF THE NHE1 CARBOXYL TERMINUS
Jessica F. Johnson, Jason T. Grosam, Diane L. Nelson,
Mark A. Wallert (Advisor), and Joseph J. Provost (Advisor)
Department of
Biosciences
Minnesota
State University–Moorhead,
The sodium hydrogen
exchanger isoform one (NHE1) is key in the regulation of intracellular pH, cell
volume, and cell motility in nearly all eukaryotic cells. Regulation of NHE1
activity occurs primarily through post-translational modification of the
cytoplasmic carboxyl-terminal tail.
Rho-Associated Kinase
(ROCK) is a serine/ threonine kinase involved in upstream signaling pathways
that regulate NHE1 activity. We propose that ROCK directly phosphorylates NHE1
in an α1-adrenergic receptor-dependent fashion. This will be demonstrated
through the use of an NHE1 carboxyl–terminal tail fusion protein, CTNHE1.
Phosphorylation of CTNHE1 via a ROCK dependent pathway will first be examined
using cell lysates after stimulation with phenylephrine, a specific
α1-adrenergic receptor agonist.
Control and
agonist-stimulated lysates will be combined with purified CTNHE1 in an in vitro
kinase assay. Phosphorylation of CTNHE1 will be assessed by Western blotting
using phosphoserine/threonine anti-bodies. To show direct phosphorylation of
CTNHE1 by ROCK, purified forms of ROCK will be combined in vitro with purified CTNHE1 and analyzed by Western blot. Subsequently,
specific ROCK phosphorylation site(s) of NHE1 will be predicted based on known
ROCK substrate sequences. Ser/Thr-to-Ala mutations of the CTNHE1 construct will
be prepared and analyzed for phosphorylation by ROCK. We expect the net results
to show that ROCK directly phosphorylates CTNHE1 in an α1-adrenergic
receptor response. Consequently our results could enable greater understanding
of disease states in which NHE1 activity is altered, such as tumor formation
and migration. This work was supported from a grant from the NIH, award number
1 R15 HL074924-01A1.
SURFACTANT PROTEIN B AND SURFACTANT PROTEIN C CHARACTERIZATION AND EXPRESSION IN Xenopus laevis
Natalie S. Johnson and Brian
Hyatt (Advisor)
Department of Biological Sciences
Surfactant Protein B (SP-B) and Surfactant Protein C
(SP-C) are molecules expressed exclusively in lung tissue. They are expressed
early in lung development and continue to be expressed in the adult lung.
Previously these two genes had been sequenced only in mammals. The internal
gestation of mammals has made it difficult to research the early development of
lungs, however. Xenopus laevis was
therefore examined as a possible model for allowing easier access to, and
manipulation of, the embryo during lung development. Sequence analysis of the
coding regions of Xenopus SP-C and
SP-B determined that they have high homology with the human and mouse gene
sequences. RT-PCR and in situ hybridi-zation
techniques showed that the expression of these genes in Xenopus laevis was located exclusively in the lung tissue and was
also seen in the early stages of lung development. The expression patterns of
SP-C and SP-B in Xenopus laevis are
consistent with those seen in mammalian subjects. In light of these similarities
it is believed that Xenopus laevis
would be a good model for further study of SP-B and SP-C and may also be a good
subject for further studies on lung development.
TOXIC AND MUTAGENIC EFFECTS OF ARNICA
Nate Johnson and Gregg
Johnson (Advisor)
Department of Biological Sciences
Arnica (Arnica
It was the purpose of this investigation to test the
toxic effects of Arnica on gram – and + bacteria (Serratia marcescens, and
Saracina lutea) and on representative fungi (asperigillus, and
penicillium). We also tested the
genotoxic effect of Arnica on cultured human lymphocytes using the sister
chromatid exchange (SCE) technique as well as counts of micronuclei, and
bridges as measures of DNA damage. Our
results indicate that Arnica does not possess antibacterial or antifungal
properties. It does appear that there is
significant increase in SCE, micronuclei, and DNA bridge formation and
depressed mitotic index in cultured human lymphocytes treated with Arnica.
EFFECTS OF Rap 1 ON CELLULAR MIGRATION AND
ADHESION
Daniel Kolar and
Jennifer L. Cruise (Advisor)
Department of Biology
Cellular migration is involved in a number
of events including wound healing and development. Rap 1 is a small GTPase that
has been implicated in cell migration and adhesion. Rap is known to effect
E-cad-herins and integrin-matrix interactions, which influence cell’s
attachment to each other and to surfaces, respect-ively.
Wound assays can be used to observe the
rate of migration in monolayers of cells. In these assays, clearing cells from
a region of a culture plate is followed by photomicroscopic monitoring of
migration of cells into the wounded area. The rate, density, and pattern of
migra-tion can be analyzed in photos over time. We examined the effect of Rap 1
on the migration response in three stably transfected MDCK epithelial cell
lines. One expressed an activated Rap1 gene and one a dominant-negative form of
Rap1; a control line was stably trans-fected with an empty vector plasmid. Two
clones of each cell type were examined. We found migration to be significantly
impaired by activated Rap1, compared with controls. This suggests that Rap1
inhibits migration. We also characterized the effect of Rap 1 on the expression
of integrin-matrix interactions, using adhesion assays. Ad-hesion to three
different coatings: fibronectin, coll-agen, and BSA (control), were tested.
Cells expressing active Rap1 adhered more strongly to collagen than did
controls.
We have found that active Rap 1 decreases
mi-gration and increases adhesion. The relationship between the two processes
and the mechanism(s) of Rap1's effect requires further research.
PHOTOLYSIS OF NORFLOXACIN UNDER ENVI-RONMENTALLY
RELEVANT CONDITIONS
Andrew Korte and Kristine
Wammer (Advisor)
Department of Chemistry
Norfloxacin, a member of the
fluoroquinolone class of antibiotics, was examined to predict its photo-chemical
fate in natural waters. Contamination poses a threat to humans as low-level
environmental presence may give rise to bacterial resistance. Additionally, the
products of photolysis may also have adverse effects. Samples of a norfloxacin
solution were photolyzed using borosilicate-filtered Hg-vapor lamps and
analyzed by HPLC to determine concentrations at set time intervals. Rates for
photodegradation in deionized water at a range of pH values were compared with
those in 0.2 micron-filtered water obtained from
Photodegradation rates of norfloxacin were rapid in
both deionized water and
ANALYSIS OF VOLATILE COMPOUNDS OF
DIAGNOSTIC INTEREST USING A MICRO-DIALYSIS PROBE EXTRACTION TECHNIQUE
Ashley Kramer and Dr. Anthony
Borgerding (Advisor)
Department of Chemistry
Microdialysis has become useful in sampling
non-volatile compounds in biochemical systems such as different places in the
human body. Our lab has had success
using microdialysis sampling probes for volatile compound extraction from
aqueous solutions into the gas phase.
Experiments with breath analysis in the biomed-ical field currently use
a breathing apparatus as a diag-nostic tool, to measure volatile compounds in
the body such as acetone, formaldehyde and dimethyl sulfide. Our research lab is currently testing our
probes on these com-pounds for the long-term goal of using microdialysis as an
in-vivo method. We have analyzed these
compounds over a variety of concentrations.
Acetone, for example, was measured over a concentration range of
0.001-0.5% acetone by weight.
USE OF CORNMEAL FOR ALGAE REMEDIA-TION IN
URBAN LAKES
Scott Kronholm
and Bryan Anderson (Advisor)
Department of Biological Sciences
In nature, algae levels in lakes and
streams are usually found in relatively low numbers due to limiting factors
such as nutrient availability. Due to the use of products such as lawn care and
industrial fertilizers, which contain high amounts of nitrates and phosphates,
there can sometimes be a surplus of the normally limiting nutrients. Algal
blooms (large growths of algae) are typically found in metro area lakes and
streams due to high nutrient levels. Not only are blooms unpleasant to look at,
smell, or swim around, they can be toxic as well. Certain genera of algae
produce toxins which, if in sufficient quantity, can make those who drink the
water ill and have been known to be fatal in some cases. It has been shown that
the use of cornmeal is an effective and relatively inexpensive way to reduce
numbers of certain genera of algae. In this research I used four genera: Anabaena, Oscillatoria, Pediastrum, and Spyrogyra. The process by which cornmeal
reduces algal growth is not currently well understood; however, some theories
are currently being tested. This research deals with the application of
cornmeal rather than the process by which cornmeal effects algae.
COMPUTATIONAL STUDIES OF THE ATMO-SPHERIC IMPACT OF
CYCLOALKENE OZO-NOLYSIS
Brianna Kujala and Keith
Kuwata (Advisor)
Department of Chemistry
The hydroxyl radical is the most important oxidi-zing
agent in the atmosphere. It is responsible for oxidi-zing hydrocarbons, the
deposition of acid onto Earth’s surface, and the production of peroxyl
radicals. In the absence of light, the hydroxyl and peroxyl radicals are
produced via non-photolysis methods, most importantly through the ozonolysis of
alkenes in the atmosphere. Furthermore, because the time period over which a
single hydroxyl radical is present in the atmosphere is so small, computational
studies are needed to better determine the amounts of hydroxyl radical being
produced in our atmosphere and the rates at which it is being produced. This
study looks at the ozonolysis of cyclopropene, a model cycloalkene compound.
Through computational studies involving density functional theory and other
methods, this work attempts to completely characterize the reaction pathways
involved in this mechanism with respect to their rates and overall reaction
yields. Reaction energies, and energies of activation, for formation of the exo
and endo primary ozonides, for their cycloreversion into anti and syn carbonyl
oxides, and for their isomeri-zation into dioxiranes and hydroperoxides have
all been determined. Preliminary results, for the exo cylcoaddition transition
state as the entrance channel, give fractional yields of 0.6817 for the
dioxiranes and 0.3175 for the hydroperoxides. Yields for the endo cycloaddition
tran-sition state as the entrance channel are 0.6633 for the dioxiranes and
0.3346 for the hydroperoxides. Yields for formation of the secondary ozonide
are negligible.
LEWIS ACID/LEWIS BASE INTERACTIONS IN
HALOGEN/CYANO-BENZYLIDENEANILINES: A COMPARSON WITH SOME METHYL ANALOGUES
Marika K. Kuspa
and William H. Ojala (Advisor)
Department of Chemistry
The object of this study has been to
determine whether the two isomeric benzylideneanilines bearing a methyl group
in one para-position and a nitrile
group in the other assume identical molecular packing arrangements in the solid
state (are isostructural with each other) and whether this solid-state
similarity extends to any of the corresponding halogen/nitrile benzylide-neanilines.
A previous study showed that the isomeric p-cyano-p’-iodobenzylideneanilines pack
similarly (but not identically) due to intermolecular Lewis acid–base
interactions between the halogen atom and the nitrile group. These interactions
are absent from the bromo/ nitrile and chloro/nitrile analogues, which do not
form isostructural crystals. We have found that p-cyano-N-(p-methylbenzylidene)aniline and its
“bridge-flipped” isomer p-methyl-N-(p-cyanobenzylidene)aniline
do not pack similarly to the halogenated compounds, but they do pack rather
similarly (but not identically) to each other. The two crystal structures have
similar unit cell volumes and have similar cell axial lengths and interaxial
angles, but as in the case of the iodo/nitrile benzylideneanilines, the packing
arrangement differs at the three-dimensional level of molecular stacking. The
presence of intermolecular Lewis acid–base interactions in the solid state does
not guarantee isostructuralism for these isomers; at the same time, the
similarity between the methyl/cyano benzylide-neaniline crystal structures at
least suggests that the absence of these interactions does not preclude it.
AQUATIC INVERTEBRATE BIOTIC INDEXING OF THE
Tyler Kutscheid and
Department of Biology
Aquatic bio-monitoring is becoming an impor-tant tool
for both citizens and conservationists alike due to its ability to detect
long-term water conditions and its relative low cost. Most biotic indexes tend
to make prefer-ential use of the orders Ephemeroptera, Plecoptera, and
Trichoptera. However, most Midwestern biotic index values have been developed
specifically for
MICRODIALYSIS SAMPLING FOR THE ANAL-YSIS
OF NITRIC OXIDE
Christine C.
L'Abbe and Anthony Borgerding (Advisor)
Department of Chemistry
The purpose of this research project is to
design a noninvasive method of rapidly measuring nitric oxide in the brain.
This method allows for the study of the nature of nitric oxide and its role in
critical physiological func-tions and neurological diseases. Microdialysis
probes are used in combination with a chemiluminescence detector to analyze
nitric oxide samples at several dilute concen-trations in order to determine
the limits and efficiency of the microdialysis measurement system.
CHARACTERIZATION OF ANDROGEN REGULA-TION
OF ZEB-1 AND PSA IN 22Rz1 IN PROSTATE CANCER CELLS
Lisa LaGoo and
Bynthia Anose (Advisor)
Department of Chemistry
Human
prostatic carcinoma accounts for 30% of cancer cases diagnosed in men.
According to a February 2006 report of the American Cancer Society, the
five-year survival rate for a patient with localized prostate cancer (PCa) was
100%, but once the cancer had metastasized, the survival rate dropped to 34%.
This significant decline in prognosis with the onset of metastasis has
highlighted the need for identifying metastatic biomarkers in addition to
currently utilized cancer transformation biomarkers. The commonly assayed-for
prostate specific antigen (PSA), while touted as a transformation biomarker,
has recently proven to be problematic in the area of false positive diagnoses.
It remains, however, a hallmark gene for studying androgen regulation, as its
expression is reliably simulated by androgens such as dihydrotestoster-one (DHT).
The goal
of this project is to investigate the effects of flutamide (an anti-androgen)
and DHT on the expression of PSA and zinc finger E-box binding protein (ZEB-1).
Previous research has identified ZEB-1 as a possible biomarker for the onset of
metastasis in PCa. The gene has been shown to be androgen-regulated, and its
expression decreases sharply at metastasis. This study will confirm the
feasibility of using ZEB-1 as a PCa metastatic biomarker using the highly
sensitive technique of real-time polymerase chain reaction. The effects of 1
and 10 nM flutamide, in combination with 1 and 10 nM DHT, on expression of
ZEB-1 and PSA will be studied in 22Rv1, an androgen-responsive human prostate
carcinoma cell line.
PREPARATION
AND CHARACTERIZATION OF SYMMETRICALLY SUBSTITUTED TRIOLS AS
Brian A. Loy and
Wade A. Neiwert (Advisor)
Department of Chemistry
This research project aimed at preparing
and characterizing various triol-substituted organic com-pounds of the general
form RC(CH2OH)3 (where R can be various organic groups).
These triols are able to covalent-ly bind to redox active vanadium-oxo clusters
via self-assembly reactions. If “R” is able to support multiple triols (such as
R = benzene), then multiple vanadium complexes can be bridged by these organic
linkers, resulting in linear chains (with two triols) or two-dimen-sional
arrays (with three triols). Recent efforts have fo-cused on the preparation of
a tris-triol species with for-mula 1,3,5–C6H3(CºCC6H4CONH(CH2OH)3)3.
FT-NMR and FT-IR spectroscopy have been used to characterize the compound and
the isolated reaction intermediates, with hopes of preparing an X-ray quality
crystal of the triol for diffraction studies.
IDENTIFICATION OF WOUND RESPONSIVE GENES IN Avena sativa SEEDLINGS
USING AFLP FINGERPRINTING
Kathleen Lynch and Debra
Martin (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
All plants are faced with the dilemma that they must
compete to survive and propagate while being immobile. To protect themselves
from competitors on the surface, plants have a coating of cutin and subrin. How-ever,
if a wound occurs on the surface, the plant becomes susceptible to injurious
invaders. When injured, plants produce special proteins that assist in repair
and protect-tion against disease. Wound-induced proteins are believed to be
involved in such plant defense mechanisms. The objective of this research
project was to identify potential wound responsive genes from oat (Avena sativa). To begin, mRNA was
isolated from wounded oat leaves. The cDNA was amplified by PCR. Using
fluorescently labeled primers, the cDNA was re-amplified to generate AFLP
fragments to be analyzed on the LiCor Gene Analyzer.
THE ROLE OF
UROKINASE PLASMINOGEN ACTIVATOR IN THE REGULATION OF ERK, STRESS FIBER
FORMATION, AND NHE IN CCL39 FIBROBLASTS
Lisa Magstadt, Joe Provost (Advisor), and Mark Wallert
(Advisor)
Department of Biosciences
Minnesota
State University–Moorhead,
Cell migration
requires control of several signal-ing mechanisms including reorganization of
the actin cytoskeleton and adhesion to the extracellular matrix. Urokinase
plasminogen activator (uPA) is a thrombolytic agent that possesses a role both
dependent and indepen-dent of binding to its receptor, uPAR. Receptor
activation of uPAR localizes proteolytic activity to the leading edge of
cellular migration and facilitates cellular penetration of tissue boundaries.
Expression of both uPA
and uPAR correlates with invasive cancer cell phenotype; however, the mecha-nism
by which uPAR transduces its signals to regulate cell migration remains largely
uncharacterized. Our focus is to investigate the signaling of uPA in CCL39
fibro-blasts to determine a role for NHE in cytoskeletal remod-eling and cell
migratory events. ERK activation by uPA stimulation has been shown in a few
cell lines.
Smooth muscle cell
inhibition of the sodium hydrogen exchanger (NHE) reduces cell proliferation and
migration caused by uPA. Here we report that both the amino terminal fragment
and recombinant uPA stimulate ERK phosphorylation in a bimodal fashion. The
early peak of activity was observed within 5 minutes and a later chronic
stimulation of ERK was seen after 190 minutes. Both forms of uPA induced the
formation of stress fibers in CCL39 fibroblasts and the amino terminal fragment
of uPA induced over a two-fold increase in NHE transport. These findings
identify a potential new signaling role for uPA and suggest an important role
for NHE in cell migra-tion and invasion. This work was supported by a grant
from the NIH, Award number 1 R15 HL074924-01A1.
DETERMINING THE ELECTRONIC STRUCTURE OF
TaO USING LASER SPECTROSCOPY
Kara Manke, Tyson
Vervoort, and Thomas D. Varberg (Advisor)
Department of Chemistry
We have recorded hyperfine resolved laser
excitation spectra of the B2F5/2 –X12D3/2 and C2D 3/2 –X12D3/2 electronic transitions of TaO. The
electronic spectrum of this molecule was first explored by Cheetam and Barrow
using a grating spectrograph. A Ti:sapphire ring laser was used to analyze TaO
molecules that were produced with a hollow cathode discharge. We achieved
hyperfine resolution using the sub-Doppler technique of inter-modulated
florescence spectroscopy. A least-squares fit of the transition frequencies was
used to determine improved values for the rotational parameters and values for
the magnetic dipole and electric quadrupole para-meters of these states.
CREATION OF
A CDC 28 “KNOCKOUT” (BY GENERATING A TEMPERATURE-SENSITIVE LOSS OF FUNCTION)
MUTANT TO OBSERVE MITOCHONDRIAL INHERITANCE IN Saccharomyces cerevisae
Kyle Marthaller and Ellen Brisch (Advisor)
Department of
Biosciences
Minnesota
State University–Moorhead,
In Saccharomyces cerevisae, the inheritance
of mitochondria from mother cell to daughter bud during cell division is an
essential feature of yeast growth. The anal-ysis of mutants defective in
mitochondrial morphology and inheritance has led to the identification of a
number of proteins that control mitochondrial inheritance. This experiment
focuses on a certain gene, CDC 28, that en-codes a protein that drives the cell
through mitosis. Using PCR, a knockout construct was generated. This construct
was then isolated via gel electrophoresis and successfully purified. This
construct will be transformed into yeast cells and through the use of a
copper-induced promoter be selectively activated. Through mitochondrial
staining, the role of CDC 28 in mitochondrial inheritance will be observed.
DAY IN THE LIFE OF Daphnia:
AN INTENSIVE ACOUSTIC STUDY ASSESSING
THE PATCHI-NESS OF ZOOPLANKTON
Rachel J.
McAlpine and Leif Hembre (Advisor)
Department of Biology
Advances in technology using high
frequency sonar have allowed researchers to visualize patches of zooplankton in
large geographical areas. Sonar may be used to assess the relative importance
of abiotic versus biotic factors that influence zooplankton patchiness. In this
study sonar was used to determine the spatial distrib-ution of Daphnia in
PREPARATION AND CHARACTERIZATION OF
ZINC(II)-SUBSTITUTED POLYOXOMETALATES AS
Elisabeth
Melander and Wade A. Neiwert (Advisor)
Department of Chemistry
The goal of this project is the synthesis
and characterization of zinc(II)-substituted A-type Keggin sandwich
polyoxometalate (POM) complexes of the general form [(Zn(H2O)2)x(WO)3–x(PW9O34)2]–(6+2x)
(x = 1, 2, or 3). The trivacant [PW9O34]9–
anion was prepared and characterized according to literature methods. Treatment
of an aqueous solution of the POM with Zn2+ affords the
trisubstituted sandwich [(Zn(H2O)2)3 (PW9O34)2]12–.
Methods to substitute a W(VI) cation in place of the Zn(II) were investigated,
and isolated products were characterized by FT-IR and NMR spectro-scopy. In
addition to the interesting catalytic properties POMs possess, these
sandwich-type complexes have the potential to serve as building blocks for
inorganic–organic hybrid materials through coordination of ligands to the
sandwiched metal cations. The mono- and di-substituted complexes will limit the
polymerization and therefore serve as structural models.
SYNTHESIS AND GENETIC ANALYSIS: SMALL MOLECULE-INDUCED
PERTURBATION OF AUXIN SIGNALING IN Arabidopsis thaliana
Sarah B. Miller1,
Johann S. Bergholz V.1, 2, Paul J. Overvoorde1 (Advisor),
and Ronald Brisbois2 (Advisor)
1Department of
Biology
2Department of
Chemistry
Auxin is a plant hormone that is essential for
numerous processes in plant development. However, many of the mechanisms by
which this hormone modu-lates such processes remain unclear. Chemical genetics
provides a novel means by which to investigate the auxin response pathway in Arabidopsis thaliana. A previously
conducted high-throughput screen of 10,000 small molecules yielded four
compounds that strongly inhibited auxin signaling. Here, we have synthesized
various analogs of one of these inhibitory molecules, Compound A. Through
quantitative real-time PCR and GUS assays, we aim to assess the inhibitory
capabilities of each Compound A analog. This information will provide insight
as to the active core moiety of Compound A, which will ultimately aid us in
devising a scheme for purification of the protein target of this inhibitor.
SYNTHESIS OF
TITANIUM(IV) TRISPHENOLATE CATALYSTS IN RING-OPENING POLYMERIZA-TION
William Mitchell, Sarah Russell, and Gretchen
Hofmeister (Advisor)
Department of
Chemistry
The ring-opening
polymerization of lactide is of great interest because a variety of plastics
can be made using an annually renewable feedstock. Catalysts with high
stereoselectivity are desired to create polymers with commercial application.
Although our titanium trisphen-olate catalyst has good stereoselectivity and
excellent molecular weight control (PDI < 1.10), the mechanism leading to
stereocontrol is unclear. To better understand this system and improve catalyst
design, we have been investigating the kinetics of this reaction. Preliminary
results are presented, including the dependence of this reaction on lactide. An
induction period is observed be-fore polymerization begins, presumably due to the
forma-tion of the active catalytic species. Further work will focus around
investigating the induction period and determining the dependence of the
reaction on titanium.
THE USE OF DNA
MICROSATELLITES TO ASS-ESS REPRODUCTIVE BEHAVIOR IN FATHEAD MINNOWS (Pimephales promelas)
Jill Moes, Laura Matzke, Rebecca Lande, and Michelle
Malott (Advisor)
Biosciences
Department
The fathead minnow (Pimephales promelas) is a freshwater
fish with a wide geographic distribution. We are specifically interested in the
fish population found in
THE EFFECTS OF GNC MELATONIN ON THE HUMORAL IMMUNE
RESPONSE IN FEMALE CD-1 MICE
Ashley M. Munson and Jeanne
Minnerath (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
Melatonin, which is a natural neurotransmitter, is a
derivative of serotonin and is released by the pineal gland. Recently,
researchers have begun to discover that melatonin has many functions within the
body. Among those functions, one is to enhance an immune response. Previous
research completed at Saint Mary’s University has shown that administration of
pure, chemically defined melatonin elicits an increased humoral immune response
in mice. However, it is unclear whether or not melatonin capsules that are
commercially available to the consumer have the same effect. This research
project examined the effects of General Nutrition Center (GNC) melatonin on
antibody production in female CD-1 mice. To complete the study, 30 mice were
split into three groups and fed peanut butter with or without melatonin (GNC
melatonin or chemically defined melatonin) for nine weeks. Three weeks into the
project, the mice were immunized with the foreign proteins, cow cytochrome c and ovalbumin, to elicit an immune
response. At three different times during the experiment, blood samples were
collected and ELISAs were completed to determine whether or not melatonin
caused an increase in antibody titers. Results indicate that mice treated with
either GNC melatonin or chemically defined melatonin did exhibit an increased
antibody titer in comparison with control mice. However, this increase was not
statistically significant. These results suggest that commercially available as
well as chemically defined melatonin may help enhance the humoral immune
response in mice.
NEST
PREDATION AND HUMAN INFLUENCE ON THE
Marla Nelson and
Kathleen L. Shea (Advisor)
Department of Biology
Nest predation on the olive
ridley sea turtle (Lepidochelys olivacea)
was investigated at Ostional and Nosara beaches of Ostional National Wildlife
Refuge in
MAP kinase
phosphatase-3 Regulation in Colorectal Carcinoma
Ngozika Okoye,
Marion Zillhardt, Nicholette Zeliadt, Dr. Elizabeth Wattenberg, and Dr. Laura
Mauro (Advisor)
Departments of Animal Science and
Environmental Health Sciences
LONG-TERM OUTCOMES OF PATIENTS WITH MITRAL REGURGITATION UNDERGOING PER-CUTANEOUS
CORONARY INTERVENTION
Catherine Pastorius1,
(Advisor Lin Aanonsen1), Paul Sanders2, Timothy Henry2,
Denise Windenberg2, Jessica Wilson2, Howard Liang2,
Tom Knickelbine2, and Kevin M. Harris2
1Department of Biology
2Minneapolis Heart Institute,
Mitral regurgitation (MR) is abnormal leaking of blood
from the left ventricle to the left atrium of the heart through the mitral
valve. The most appropriate treatment for patients with MR is often debated.
Evidence suggests that MR has prognostic importance in patients undergoing
coronary artery bypass surgery. Long-term outcome of those undergoing
percutaneous coronary intervention (PCI) is less well defined. We evaluated 711
patients who underwent PCI at our institution in the year 2000 and had
qualitative assessment of MR by left ventriculography and/or echocardiography.
Perioperative death was recorded and mortality was determined by social
security death index. MR severity was divided into three strata: none (n=420,
59%), mild (n=209, 29%), and moderate to severe (n=82, 12%).
Patients with progressively more severe MR were older,
more frequently female, with lower left ven-tricular ejection fraction (EF) of
45±14.2, higher inci-dence of previous myocardial infarctions, and higher
creatinine (all p<0.003). Patients with ischemic MR undergoing PCI have
significantly decreased survival rates over 30 days, 1 year, and 5 years, and
MR is an important predictor of survival. Given a 5-year survival of only 58%,
further study will need to evaluate whether concomitant percutaneous valve
repair or coronary artery bypass with repair would improve outcome in patients
with moderate to severe MR requiring revascularization.
MEASURING ADVENTITIOUS ROOTING: AN ASSAY TO DETERMINE INDIVIDUAL FUNCTION AMONG THE Aux/TAA GENESBen Pederson, Can Sungur, Amelia Mueller, Sam Nalle, and Paul Overvoorde
Department of Biology
The current picture of the spatial and functional relationships between each of the 29 Aux/IAA genes in Arabidopsis is incomplete. Together with the ARF gene family, they are involved in auxin-mediated changes in gene expression. Since the Aux/IAA proteins are able to homo- and heterodimerize, the number of combinatorial interactions is large, and offers a possible molecular mechanism to explain developmental events mediated by auxin. One such event is the formation of adventitious roots, which can originate in a variety of tissue locations from clusters of mature cells that renew their cell division activity and develop into a root apical meristem in a sim-ilar fashion as lateral roots. The ability of Arabidopsis to form adventitious roots provides it a flexible way to re-spond to environmental changes or injury and is a quant-ifiable trait that reflects auxin metabolism.In order to piece together the relationship between the Aux/IAA genes in this auxin-mediated event, and to investigate the potential role of ethylene in the gene-expression pathways governed by auxin, we deve-loped an assay to assess differential capacities of single, double, and triple knockout mutants of the Aux/IAA gene family to form adventitious roots. Furthermore, the application of exogenous auxins allowed us to amplify the formation of adventitious rooting, allowing us to better quantifiably analyze the extent to which each of the Aux/ IAA genes tested was responsible for the formation of adventitious roots. We determined that the triple knockout Aux/IAA (i5i6i19) mutant had an increase in adventitious root formation when compared with single knockout mutants of the same genes. This demonstrates that the IAA proteins translated by i5, i6, and i19 overlap in function, working together to dampen the influence of both endo- and exogenous auxins in adventitious rooting. Moreover, the application of ethylene appears to increase the number of adventitious rooting in most genotypes. These data were further supported by the lack of adven-titious rooting within the ethylene-insensitive mutants etr, ctr and ein. EXPLORING DINOSAUR PALEOECOLOGY OF A VERTEBRATE
MICROFOSSIL ASSEMBLAGE IN THE LATE CRETACEOUS LANCE FORMATION,
Walter S. Persons and Raymond R. Rogers (Advisor)
Geology Department
Here I attempted a
paleoecological reconstruct-tion using data collected from a vertebrate
microfossil assemblage found in the Lance Formation near Glen Rock,
THE SYNTHESIS OF META-CHLORO- AND META-BROMO- ANALOGS OF
CAPSAICIN: POTENTIAL NEW ANALGESIC AGENTS
Katherine M. Phalen and
David B. Rusterholz (Advisor)
Department of Chemistry
University of Wisconsin–River
Falls,
Capsaicin is the
substance in hot chili peppers that is responsible for causing the burning pain
sensation for which these peppers are so well known. When a capsaicin molecule
comes in contact with one of these sensory nerves, it first attaches to a
receptor molecule called TRPV1. The goal of this research project was to create
several new substances that have affinity for the TRPV1 receptor, but do not
activate it. It is hoped that biological testing will reveal that these
compounds have the qualities needed in a useful pain-relieving drug. The target
structures were based on the capsaicin structure with several modifications.
Most important, the target structures contained atoms of bromine or chlorine in
the position where capsaicin has a methoxy group. This change was expected to
enhance the pain-relieving qualities of the resulting compounds. The synthesis
of the target compounds was accomplished by a convergent synthetic
strategy. The final step involved the
formation of a thiourea linkage between an isothiocyanate precursor bearing the
hydrophobic C region and a benzylamine bearing the halogen-modified A region.
Details of the synthesis will be presented and discussed.
A NON-RADIOACTIVE ASSAY TO DETERMINE
ISOFORM ACTIVATION OF PLD BY PHENYL-EPHRINE IN CCL39 CELLS
Danielle E.
Rastedt, Mark A. Wallert (Advisor), and Joseph J. Provost (Advisor)
Phospholipase D (PLD) is an enzyme found
in the cells of higher mammals and plants. The process of PLD acting on
phosphatidylcholine (PC) to produce phospatidic acid (PA) and choline is
important in cell signaling. PA acts as a bioactive lipid activating a number
of protein kinases and other effectors and can be further metabolized to
diacylglycerol, an activator of protein kinase C (PKC). There are two isoforms
of PLD, PLD1 and PLD2. PLD1 activity is activated by the small G proteins RhoA
and ARF as well as PKC, while PLD2 is constitutively active and can be
stimulated by ARF. There is great interest in understanding which isoform is
activated by various hormones. Therefore, several methods have been developed
to determine its enzymatic activity. The current method used to determine
enzymatic activity is an in vivo PLD assay using radioactive lipids. Our
plan is to use fluorescent labels to measure PLD activity in a non-radioactive
assay. Three types of fluorescent lipids were used in these experiments. Two
free fatty acids 4,4-difluoro-5-octyl-4-bora-3a,4a-diaza-s-indacene-3-pentanoic
acid (BODIPY C8, C5);
4,4-difluoro-5-methyl-4-bora-3a,4a-diaza-s-inda-cene-3-do-decanoic acid (BODIPY
C1, C12); and 1-myristoyl-2-[, 12-[(7-nitro-2-1,
3-benzoxadiazol-4-yl)amino] dodecan-oyl]-sn-glycero-3-phosphocholine (NBD-PC).
We found that both NBD-PC and BODIPY C1, C12 but not
BODIPY C8, C5 were incorporated into the membrane as PC.
Furthermore, there is a dose- and time-dependent manner in the labeling of
starved CCL39 fibroblasts. We plan to show which PLD isoform(s) is activated by
stress hormones in CCL39 cells using this technique.
THE EFFECTS OF EXPOSURE TO DIMETHYL-SULFOXIDE ON MALE
FERTILITY IN Mus musculus
Jennifer Reiman and Randy
Krainock (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona MN.
Interruptions in the process of spermatogenesis can
affect the fertility of the male. Dimethylsulfoxide (DMSO), a common chemical
solvent, was previously found to have a negative affect on the male fertility
of Mus musculus: the data, however,
were ambiguous. The objective of this experiment was to test if there was a
negative affect on male fertility when DMSO was admin-istered topically or
orally. Mice were sorted into three groups: a control group, a topically
treated group, and an orally treated group. The topical and oral group mice all
received 0.61 μl DMSO/day. After 36 days, the control and treated males
were mated with untreated females. No significant differences were found
between the groups’ offspring litter quantities. Testes were collected and the
measured mass and length demonstrated no significant differences among the
groups. Sperm was extracted from the epididymis and vas deferens: the total
sperm counts and motility were not significantly different. There was a
significantly greater number of abnormal sperm morpho-logies with DMSO
exposure. Gas chromatography mass spectrometer analysis was conducted on the
blood serum of the male mice. There was no detectable DMSO within the serum
samples from the mice.
INTERPRETING
GENETIC VARIATION IN LO-LLYPOP DARTERS (Etheostoma neopterum) AND
BLACKFIN DARTERS (Etheostoma nigripinne) FROM
Elizabeth Rivers and Jean Porterfield (Advisor)
Department of
Biology
The lollypop
darter (Etheostoma neopterum) and
blackfin darter (Etheostoma nigripinne)
are members of a group of freshwater fishes called fantail darters (subgenus Catonotus). Recent phylogenetic analysis
of cytochrome b DNA sequences of the
20 species of Catonotus suggested
introgression of E. nigripinne mitochondrial
DNA (mtDNA) into E. neopterum
populations via hybridization. In order to test the hypothesis that
hybridization has occurred between these two species, additional E. nigripinne and E. neopterum were sampled from populations from 11 sites in and
around the Shoal Creek system in
THE EFFECTS OF ESTROGEN-TREATED Bonasa
umbellus EGGS IN REGARD TO FERAL PREDA-TION
Anna Robertson and Ray Faber
(Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
In southeastern
Chicken eggs were injected with 10 mg of
17α-ethinyl estradiol mixed in 1 ml of canola oil. The eggs were then
rinsed in a weak solution of grouse scent to simulate natural grouse eggs.
Beginning on March 1st, three separate
sites, each with 90 eggs, were established and monitored frequently for egg
consumption for a period of two weeks. Two sites had treated eggs, the third
served as a control. On March 31st, a second two-week period of
monitoring egg consumption of untreated eggs began in the same locations.
Ultimately, if a correlation can be shown between estrogen-treated eggs and
decreased predation rates, the placement of estrogen-treated eggs before the
season of B. umbellus begins may
become an accepted management practice.
CHARACTERIZATION OF INSULIN ADSORP-TION TO
GOLD-COATED QUARTZ CRYSTAL SURFACES
Amy Rohly, Megan
Schwartzbauer, and Ken Rohly (Advisor)
Department of Chemistry
The purpose of this study is to evaluate
the adsorption profile of human recombinant insulin on gold surfaces.
Gold-coated quartz crystals were initially sub-jected to a cleaning procedure
in order to remove contam-inants from the surface. They were then loaded onto a
quartz crystal microbalance (QCM; Q-sense E4), which was the primary method of
measuring the adsorption profile. The gold crystals vibrate at approximately
4.95 MHz and adsorbed insulin changes the vibrational fre-quency, which can be
converted to mass. The dissipation pattern yields information about the
orientation of the insulin on the surface. The gold crystals were also char-acterized
by atomic force microscopy (AFM) after the cleaning procedure and after protein
adsorption to image the change in surface topography. Since gold has a high
affinity for adsorbing impurities, the goal is to obtain cleaning and adsorption
procedures that yield repro-ducible data.
1,10-DIOXA-4,7,13,16-TETRAAZACYCLOOCT-ADECANE
CAUSES LEAD (II) TO SELF-LUMIN-ESCE WHEN EXCITED BY A LASER
Robert Rounds†
and Marc Percovik* (Advisor)
Departments of Chemistry
†
*
The 18-crown-6 derivative
1,10-dioxa-4,7,13,16-tetraazacyclooctadecane was synthesized. The compound was
mixed with lead(II) nitrate in water, yielding a com-plex. This complex was
then characterized using NMR and UV-VIS spectroscopy. Emission of the complex
at low temperature was examined with a Nd:YAG laser. It was demonstrated that
the binding of the macrocycle lig-and enables the lead(II) ion to emit in the
500-nm range when excited by the laser, and that the empty ligand is incapable
of emission in the observed region without the lead(II) ion.
SOLID-STATE STRUCTURES OF SOME ortho-SUBSTITUTED
BENZYLIDENEANILINES
Benjamin L.
Sanders and William H. Ojala (Advisor)
Department of Chemistry
We describe isomeric benzylideneanilines
as “bridge-flipped” isomers if they differ only in the orientation of the
linkage connecting the two aryl groups (Ar–CH=N–Ar’ vs. Ar–N=CH–Ar’). The
existence of crystalline benzylideneanilines in which disorder exchanges the
–CH= and =N– moieties has led us to consider whether bridge-flipped
benzylideneanilines could be co-crystallized to produce new solid-state
materials. Because co-crystallization requires similarity in molecular
conformation, we have determined the X-ray crystal structure of a
benzylideneaniline bearing an ortho-hydroxyl
group to compare the conformation and packing arrangement of this molecule with
those of its bridge-flipped isomer. Intramolecular H-bonding produces two
different conformations for these isomers, but both are nearly planar. Here we
compare the crystal structures of these benzylideneanilines with that of a
recently prepared analogue in which the hydroxyl group has been replaced by a
fluoro substituent. All three benzylideneanilines assume different packing
arrangements and engage in different intermolecular interactions in the
crystal.
OPTIMIZATION
OF A PROPOSED UNDERGRAD-UATE BIOCHEMISTRY LABORATORY INVOL-VING MOLECULAR
BIOLOGICAL TECHNIQUES
Noël Santora and
Ashley Mahoney (Advisor)
Department of Chemistry
This project involves the integration of
numerous biochemical and molecular biological techniques in order to develop a
semester-long undergraduate biochemistry laboratory. This laboratory will
include a series of related experiments designed to reinforce the significance
and versatility of the employed techniques. The objectives of the proposed
laboratory are to subclone the β-galactosi-dase gene from a mammalian
vector into an E. coli vector using
specific restriction endonucleases, to express pos-itive clones and purify
β-galactosidase using a nickel resin, to visualize the enzyme of interest
using SDS–PAGE and Western blotting, and to determine the activity of
β-galactosidase using a specific assay.
CHROMOSOME TRANSGENICS IN OAT–MAIZE ADDITION LINES:
IMMUNOCYTOLOGICAL ANALYSIS OF THE ENZYME MALATE DEHY-DROGENASE
Krista Schoeder, Jeanne
Minnerath (Advisor), and Richard Kowles (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
Oat-maize chromosome addition lines have been
successfully generated at the
AN INCREASE IN THE MITOTIC INDEX OF Vicia faba ROOT TIP CELLS WITH MITOGEN COMBI-NATIONS
Beth Schubert and Richard
Kowles (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
Many studies depend on obtaining an increase in
metaphases and a spread of visible chromosomes in cell division. In order to
obtain visible chromosomes such as these in high frequency, the cell cycle must
be interrupted in metaphase by disallowing spindle fiber formation. In these
experiments, the lateral root tips of Vicia
faba were treated with colchicine, a chemical that disallows spindle fiber
formation, as well as phytohemaglutinin (PHA) and hydroxyurea (HU), which are
both mitogens. In all combinations, an increased number of mitoses coupled with
the lack of spindle fibers resulted in an overall higher mitotic index in Vicia faba root tips. The mitotic index
of root tip cells treated in colchicine (10.95%) was higher than that of root
tip cells treated in either PHA (6.86%) or HU (4.61%) (p < .001 in both
instances). However, cells treated with PHA and HU together, but without colchi-cine,
did not have a significantly higher mitotic index than the control group
treated in water (p = .45). The highest mitotic indices were achieved through
treatments consis-ting of one mitogen (either PHA or HU) plus colchicine
(14.31% and 13.58%, respectively). Using these combina-tions, the mitotic index
was increased over colchicine by itself and nearly 6-fold over the control
group (mitotic index = 2.75%) (p < .001). The reason for the lack of
increased mitogenic effects in the presence of both mito-gens may be due to an
interaction between PHA and HU. Increasing the mitotic index has useful
applications with regard to karyotyping, in
situ hybridization, and other
cytogenetic studies.
INVESTIGATION OF EFFECTS OF TESTOSTER-ONE DERIVATIVES
ON HUMAN PROSTATE CANCER
Jamie K. Schwendinger and
Bynthia M. Anose (Advisor)
Department of Chemistry
Human prostatic carcinoma is initially an exquisitely
androgen-responsive cancer. Clinical admin-istration of anti-androgen steroids
promotes a rapid regression of the disease; however, in time, the cancer
frequently recurs in a far more aggressive form. The resurgent prostate cancer
is typically both metastatic and resistant to androgen ablation. Past research
had implicated the testosterone derivative dihydrotestosterone (DHT) as the
most potent stimulator of prostate cell growth; this hormone has therefore been
the one primarily targeted for androgen ablation. However, many analogs of DHT
exist that have not been examined or therapeutically characterized.
In our study, the chemically similar testosterone
propionate and dehydroisoandrosterone will be assayed for androgenic
capabilities and the potential to stimulate uncontrolled prostate cell growth.
22Rv1 (a human prostatic cancer cell line) will be treated with 10 nM DHT,
testosterone propionate, or dehydroisoandrosterone. The effects of these
mitogens on the expression of the growth-stimulating gene prostate-specific
antigen (PSA) will be tested. PSA mRNA levels will be quantified via the highly
sensitive, reverse transcription real-time polymerase chain reaction,
technique. Stimulation of PSA expression by DHT is both measurable and
clinically significant, and as such provides an excellent control for
investigating potentially androgenic agents.
EFFECTS OF PRESCRIBED BURNING ON AVIAN USE OF RESTORED
PRAIRIES
Rachel Spike and Dr. Jeff
Port (advisor)
Department of Biological Sciences
Periodic fire has long been recognized as a key
component of the North American grassland ecosystem. The importance of
fire in suppressing woody growth is well documented and its use to control
invasive species is a commonly practiced management tool. During the
summers of 2003-2005, data was gathered for the purpose of documenting the
impacts of a controlled burn on songbird populations utilizing a 21 acre
restored prairie. Data collected during 2003 and 2005 comprise non-burn
years and provided the opportunity to monitor the avian populations one year
pre- and post-burn. The most prominent species were the Clay-colored
Sparrow (Spizella pallida), Sedge
Wren (Cistothorus plantensis),
and Song Sparrow (Melospiza melodia).
Fewer foraging adults birds (= 21.67, SD = 4.76) and only two nests were observed during the burn
year, while many more adults (= 52.14, SD =3.17) and 26 and 34 nests were located during the non-burn
years of 2003 and 2005, respectively. This study suggests that bird
populations can quickly recover from small scale periodic fires and nearby
refugia may aid in this recovery.
INTERMOLECULAR INTERACTIONS AND MO-LECULAR
PACKING IN ISOMERIC BENZYLID-ENEANILINES
Jill M. Spude and
William H. Ojala (Advisor)
Department of Chemistry
Pairs of benzylideneanilines we have
designated “bridge-flipped isomers” differ only in the orientation of the chain
or bridge of atoms connecting the two aryl groups; the isomerism is Ar-CH=N-Ar’
vs. Ar-N=CH-Ar’. Our goal is to prepare new solid materials having properties
that can be controlled or modified by co-crystallizing various proportions of
bridge-flipped benzylideneaniline isomers. Mutual solid-state solubility is
most extensive for components that have the same molecular packing arrangement
in their respective crystals, so we are preparing benzylideneaniline bridge-flipped
isomeric pairs and determining their crystal structures to identify
isostructural pairs that would be especially suitable for co-crystallization.
Among these structures we have recently discovered our first isostructural
pair: 2-trifluoromethyl-N-(2-methylbenzyl-idene)aniline
and 2-methyl-N-(2-trifluoromethylbenzyl-idene)aniline.
Unlike the only other isostructural bridge-flipped benzylideneanilines of which
we are currently aware, 4-chloro-N-(4-methylbenzylidene)aniline
and 4-methyl-N-(4-chlorobenzylidene)aniline,
our compounds assume an ordered molecular packing arrangement in the solid
state.
CELL CYCLE ANALYSIS OF MURINE B-LYM-PHOCYTES GROWN IN
THE PRESENCE OF MELALEUCA OIL
Tom Stewart and Debra Martin
(Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
Melaleuca oil is a natural health product that is
manufactured in a natural process, and therefore the FDA does not regulate it.
Melaleuca oil is isolated from the Australian tea tree and is said to have
healing affects on a multitude of different ailments including both topical and
internal medical issues.
Previous research has shown that Melaleuca oil had an
inhibitory effect of on mammalian cell growth and viability. This experiment
was intended to determine if the cell cycle of the B-lymphocytes is what the
Melaleuca oil is affecting. The cells used were murine Z70, a pre B-lymphocyte.
Suspensions of these cells were treated with a concentration of Melaleuca oil
that was known to have inhibitory affects on cell division (0.01%). Control sus-pensions
of the same cells were treated with glycerol in the same concentration. The
suspensions were then anal-yzed using flow cytometry to determine the possible
cell cycle effects. The cell cycle results from the flow cyto-meter will be
presented and discussed.
PHENYLEPHRINE STIMULATES CELL MIGRA-TION THROUGH
PHOSPHOLIPASE D ISOFORM 1 AND NOT ISOFORM 2
Lisa Streitz, Blake Heinz,
Joe Provost (Advisor), and Mark Wallert (Advisor)
Department of Biosciences
Minnesota State University–Moorhead,
Phospholipase D (PLD) is involved in tumor-genesis in
several cell lines through the formation of phosphatidic acid (PA) and its
downstream metabolites. PLD regulates proliferation and cytoskeletal rearrange-ments.
Two mammalian PLD isoforms are known: PLD1 and 2. Small G proteins, protein
interactions, and protein kinases regulate both. PLD2 is thought to be the
predom-inant isoform involved in signaling. Our experiments sought to determine
the PLD isoform responsible for mitogenic events. Phenylephrine (PE), an
α1-adrenergic receptor agonist, leads to the activation of ERK, stress
fibers, and cell migration in Chinese hamster lung fibro-blasts. Using
dominant–negative (DN) PLD isoforms, we determined that PLD1 is responsible for
these actions.
In earlier studies, 50 µM PE stimulated ERK 3–5 fold
in a PLD-dependent fashion. Expression of DN PLD 1 but not 2 decreased PE
induced ERK activation. Addi-tionally, in stress fiber experiments,
transfection with DN PLD2 had little effect while DN PLD1 abrogated PE-induced
stress fibers. In wounding assays, PE enhanced cell migration. DN PLD1
specifically blocked this increase. Preliminary data suggest that cells
transfected with DN PLD2 migrate into the wound whereas cells with DN PLD1 do
not. Our data show that PLD1, not PLD2, mediates α1-adrenergic regulation
of migratory events and define a unique role for PLD1 in signaling. This work
was supported by a grant from the NIH, Award number 1 R15 HL074924-01A1.
INFLUENCE OF PHOTOPERIOD ON MAMMAL-IAN
CIRCADIAN FUNCTION: CAN MY MOUSE TELL SUMMER FROM WINTER?
Jeremy J.
Stubblefield, Leo S. McNamara, Kumiko Ijichi, and Dwight E. Nelson (Advisor)
In
mammals, circadian rhythms in behavior and physiology are driven by endogenous
circadian oscillators. Environmental light cycles entrain these central
pacemakers to synchronize an organism’s internal physiology and behavior with
daily changes in the environment. Seasonal modulations of behavior and
physiology are also thought to involve the circadian system through the effects
of daylength on circadian release of pineal
melatonin. We are examining photoperiod-induced changes in the circadian system
in C57BL/6 mice―a strain
commonly regarded as insensitive to photoperiod due to a lack of melatonin.
Mice (n = 12/group) were entrained to long (16L:8D) or short days (8L:16D) and
then released into constant darkness (DD). Light pulses were delivered to each
mouse in DD to assess the photic responsiveness of the circadian system using
phase shifts. Free-running period and duration of activity were also measured.
To test whether the full duration of light was necessary for photoperiodic
changes, we also tested mice (n = 12/group) pre-entrained to “skeleton” LD
cycles that matched the short day (1h L:6 h D:1h L:16h D) and long day
photoperiod (1h L: 14 h D: 1h L:8h D). Mice entrained to long days displayed
significantly smaller shifts (-82+/-11min) than mice entrained to short days
(-167+/-11min; ANOVA; Tukey, F=19.15, P<0.0001). Shifts following full
photoperiods were not significantly different from those measured following
skeleton photoperiods (ANOVA; Tukey, P>0.94). We obtained similar results
for circadian period and duration of activity. Surprisingly, there is a very large
influence of photoperiod on circadian functions in “non-photoperiodic” C57BL/6
mice.
OXIDATION-RESISTANT RIBONUCLEASE INHIBITOR
Can Sungur, Anna Krawisz, and
Kimberly A. Dickson (Advisor)
Department of Biology
Ribonuclease inhibitor (RI) is a
cytosolic protein that inhibits the activity of ribonuclease A and angiogenin
by binding to their active sites with fentomolar affinity. Its previously
described anti-angiogenic properties can currently only be of use intracellularly
due to the oxid-ation sensitivity of RI. This research attempts to create a
ribonuclease inhibitor that is oxidation-resistant by exchanging 11 cysteines
for other amino acids. The amino acid substitutions were chosen to preserve the
polarity and bulk of the cysteines; this avoids interrupting the second-dary
structures of RI. Mutations were verified by sequen-cing. Binding assays were
conducted to characterize the affinity of mutagenized RI for RNase A. This
oxidation-resistant RI may have important implications for the extracellular
inhibition of angiogenin, and thus, for the prevention of angiogenesis and
tumor metastasis. Also, it may prove to be a valuable laboratory reagent for
explor-ing or modulating interactions with ribonucleases.
ACTIVATION OF MATRIX METALLOPROTEIN-ASE 9
BY PHENYLEPHRINE REQUIRES SODIUM HYDROGEN EXCHANGER 1
Jennifer M.
Taves, Joseph J. Provost (Advisor), and Mark A. Wallert (Advisor)
Biosciences Department
Matrix metalloproteinases (MMP) are a
group of enzymes that play a critical role in digesting the extracellular
matrix. Degradation of the extracellular matrix by MMP in migrating cells
provides a vital function for tumor metastasis and angiogenesis. The link
between extracellular MMP activity and the sodium hydrogen exchanger (NHE) has
been suggested, yet not identified. We studied the relationship between NHE and
MMP activity in CCL39 fibroblasts containing NHE1, PS120 cells (NHE1 null
derived from CCL39 cells), and PS127 cells (PS120 cells expressing NHE1).
Initial studies with CCL39 cells found resting cells had moderate MMP9
activity. This activity increased 2.5 fold after 12-hour phenylephrine (PE)
stimulation. Western blot analysis of culture media identified MMP9. We found
MMP9 activity was dependent upon expression and activation of NHE1. In both
CCL39 and PS127 cells, MMP9 was activated in the presence of 100 µM PE. In
PS120 cells no MMP was activated in the presence of PE. Incubation of cells
with amiloride before PE addition resulted in a notable decrease in MMP9
activation compared with control. Incubation of cells with 0.5% butanol prior
to PE stimulation decreased MMP9 activity similar to the control level, while
expression of either dominant–negative phospholipase D1 or 2 caused a decrease
in MMP9 activity less than untransfected cells. This work, for the first time,
describes an agonist-induced relationship between NHE1 and MMP and a new
potential role for NHE1 in tumor formation. This work was supported by a grant
from the NIH, Award number 1 R15 HL074924-01A1.
SMALL MAMMAL
VEGETATION PREFERENCE IN RESTORED PRAIRIE
Jennifer Thorson and Teresa
DeGolier (Advisor)
Department of Biology
One of the
difficulties in restoring damaged habitats is knowing what made up the original
habitat and what components would most benefit the organisms in the habitat. In
prairie restoration it is important to determine carefully what vegetation
types would be optimal for the land, the vegetation, and the animals in the
habitat. This study examines (1) four different types of vegetation on old
farmland that has been converted to restored prairie, (2) the small mammals
that utilize these restorations, and (3) effects of restoration burns on the
small mammal populations. The four types of vegetations were old fields
composed of cool-season grasses, low-diversity-warm season grasses,
high-diversity-sixth-year plantings, and high-diversity-seventh-year plantings.
Small mammals including the meadow vole (Microtus
pennsylvanicus), meadow jumping mouse (Zapus
hudsonius), and white-footed mouse (Peromyscus
leucopus) were trapped, marked, and released. Zapus hudsonius showed strong preference for
low-diversity-warm-season grasses following a burn, while Microtus pennsylvanicus showed a strong preference for cool-season
grasses following a non-burn year. These results reject the null hypothesis
that small mammal populations are independent of vegetation type. These results
also support the require-ment of a diversity of reconstruction types to support
a diversity of mammal types.
HOW
DOES HOSTING THE OLYMPIC GAMES IMPACT EMPLOYMENT IN THE
Lee Tucker and Dr.
Mark Kanazawa (Advisor)
Department
of Economics
Despite the
size and prestige of the Olympic Games, few studies exist to determine whether
or not the Games benefit host cities. Existing studies suggest that the
Olympics may lead to increased employment, but they reach little consensus on
the size or length of that impact. Controlling for the effects of GDP and price
levels, I measure the size and shape of the “Olympic effect” with a series of
time-period dummies and a fixed-effects model. My study examines all Summer
Games from 1984 to 2004 in the first panel study of employment surrounding the
Olympics. Using a Prais–Winsten method to correct for heteroscedasticity and
AR(1) autocorrelation, I find evidence of a significant employment increase
lasting in general from 6 years before to 1 year after the Olympic Games, with
a marginally significant boost lasting up to 8 years afterward. I also find
that higher Olympic expenditures are negatively correlated with the size of the
Olympic effect, and that the employment impact of the Olympics may be larger in
wealthier countries.
CHROMOSOME TRANSGENICS IN OAT–MAIZE ADDITION LINES:
IMMUNOCYTOLOGICAL ANALYSIS OF THE ORGANELLE ENZYME MAL-ATE DEHYDROGENASE
Autumn Valk, Jeanne Minnerath
(Advisor), and Richard Kowles (Advisor)
Department of Biology
Saint Mary’s University of Minnesota, Winona, MN
Oat–maize addition lines result from the
cross between oat plants (C3 photosynthesis) and maize (C4 photosynthesis). One
complete maize chromosome is successfully incorporated into the oat genome. The
lines are generated at the
SYNTHESIS AND
CHARACTERIZATION OF N-PHENETHYLPYRIDINECARBOXAMIDES
AS POTENTIAL INDUCERS OF APOPTOSIS
Brianna Zemke and
Karl P. Peterson (Advisor)
Department of Chemistry
University
of Wisconsin–River Falls,
Apoptosis is a biological process in which
cells “switch-on” a series of pathways that lead to programmed cell death. This
process operates to control cell growth and tissue organization throughout the
life of an organism. Faulty regulation of apoptosis has been implicated in such
common disease states as Alzheimer’s disease, Parkinson’s disease, and cancer.
Small molecules that have the ability to induce or inhibit apoptosis are of
tremendous interest as potential pharmaceutical agents and as tools to study
the molecular biology of apoptosis. Studying these types of molecules provides
insight into the mechanism of how thet interact in the apoptotic pathways.
Understanding these interactions could allow for new small molecules to be
designed that have an enhanced ability either to induce or inhibit apoptosis.
The synthesis and characterization of a series of N-phenethylpyridinecarboxamides that bear structural similarity to
compounds recently reported to selectively induce apoptosis in cancer cells
will be presented.