Browsing Student Research Forum 2006 by Title
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Onyszchuk, Gregory (July 7, 2006)[more][less]
Abstract: Each year, traumatic brain injury (TBI) claims over 50,000 lives, and leaves 35% of survivors with long term disabilities. Elderly adults often suffer greater morbidity and mortality from TBI. Despite the large and increasing burden of TBI in the elderly, little research has been done to investigate how old age modulates the mechanisms involved in damage and repair after TBI. In previous work, we established a mouse model of sensorimotor TBI, using a controlled cortical impact (CCI) device, magnetic resonance imaging (MRI), and a simple set of behavioral assessments. We now present data regarding age-related questions, using adult male mice (5-6 months old), and aged male mice (22-24 months old). Preliminary data from MRI indicates that while lesion volumes at 14 days post-injury are similar, the extent of edema at 24 hours may be greater in the aged animals (n=4 adult, n=4 aged), suggesting a greater degree of excitoxicity or inflammation. Preliminary data from coronal brain sections stained with the anionic fluorescein Fluoro-Jade B (n=3 adult, n=3 aged), a marker for degenerating neurons, indicate increased damage to hippocampal structures in the aged group, suggesting increased vulnerability of these neurons in the aged brain. Behavioral evaluations (n=8 adult, n=5 aged) show trends towards greater Rotarod deficits in the old animals, and greater deficits in forelimb footfaults in the gridwalk test. Differences in behavioral outcome, MRI and extent of cell death will allow assessment of mechanistic hypotheses. Description: Neuroscience IV Room 1028 Dykes 3:36 PM Abstract 180 URI: http://hdl.handle.net/2271/180 Files in this item: 1
03_36_Onyszchuk_180.ppt (2.635Mb) -
Guggenmos, David (June 30, 2006)[more][less]
Abstract: Nonalcoholic steatohepatitis (NASH) is an inflammation of the liver, usually found in conjunction with Type II diabetes, and results in fibrosis and a buildup of fatty acids. A current mouse model of this disease combines a knockout of the leptin receptor (db/db) and a methionine and choline deficient (MCD) diet. Most fatty acids are synthesized in the liver and transported to the brain, where they are essential for the structure and function of the nervous system. Due to the growing prevalence of type II diabetes and NASH, a pilot study in the mouse model was conducted to see what effect this disease had on fatty acid composition in the brain. Wild-type and db/db knockout mice were maintained on standard or MCD diets for 4 weeks. Whole brain total phospholipids were quantified using thin layer and gas chromatography. Compared to the wild type without the MCD diet, the NASH model (db/db knockout with MCD diet) had significant differences in five of the 24 fatty acids measured (P<0.05) by ANOVA and Tukey’s test. Increases were observed in fatty acids 16:1 (+20%), 20:3n6 (+8%), and 22:5n3 (+51%), whereas decreases in fatty acids 20:1n9 (-10%) and 22:5n6 (-36%) were detected. These fatty acid alterations were the result of the combined effect of the knockout and the MCD diet. These observations suggest that alterations in brain phospholipid fatty acid composition may occur in NASH. The functional significance of these alterations must be determined in future studies. Description: Neuroscience II Room 1028 Dykes 10:12 AM Abstract 156 URI: http://hdl.handle.net/2271/151 Files in this item: 1
10_15_GUGGENMOS_156.ppt (246.7Kb) -
Jones, Karra (May 23, 2006)[more][less]
Abstract: Diabetic neuropathy (DN) is a common complication of both diabetes mellitus type I and II. DN has traditionally been described as a “dying-back” neuropathy, where the distal ends of sensory axons degenerate and denervate peripheral tissues. Patients with DN can show a loss of large- and/or small-diameter sensory fibers. When large fibers are involved, the patients exhibit proprioceptive deficits and impaired balance. Muscle spindles are innervated by both sensory and motor neurons and send proprioceptive information about the muscle to the central nervous system. To date, no studies have specifically addressed the innervation of muscle spindles in the setting of DN. We hypothesize that diabetes-induced denervation of muscle spindles underlies, in part, the development of proprioceptive abnormalities in DN. To test this hypothesis, we utilize a mouse model of type I diabetes induced by streptozotocin. To explore the relationship between muscle spindle deficits and proprioception, we are evaluating the proprioceptive abilities of control and diabetic mice using a rotorod, which tests coordination and balance. In addition, muscle spindle innervation is evaluated in the gastrocnemius muscle using immunohistochemical techniques. Using antibodies against S46 to visualize spindle bag fibers and neurofilament heavy chain to visualize sensory and motor axons innervating the spindles, and bungarotoxin to label the neuromuscular junction, the sensory (Ia and II) and motor (gamma) innervation of the spindle is assessed. Overall, these results will provide important information about the relationship between muscle spindles and proprioceptive deficits in DN. Description: Neuroscience I Room 1028 Dykes 9:08 AM Abstract 197 URI: http://hdl.handle.net/2271/88 Files in this item: 1
09_08_Jones_197.ppt (1.111Mb) -
Schulze, Ryan (June 29, 2006)[more][less]
Abstract: Borrelia spirochetes are unique among diderm bacteria in their abundance of surface-displayed lipoproteins, some of which play important roles in the athogenesis of Lyme disease and relapsing fever. To identify the lipoprotein-sorting signals in Borrelia burgdorferi, we generated chimeras between the outer surface lipoprotein OspA, the periplasmic oligopeptide-binding lipoprotein OppAIV and mRFP1, a monomeric red fluorescent reporter protein. Localization of OspA and OppAIV point mutants showed that Borrelia lipoproteins do not follow the '+2' sorting rule which targets lipoproteins to the cytoplasmic or outer membrane of Gram-negative bacteria via the Lol pathway. Fusions of mRFP1 to short N-terminal lipopeptides of OspA, and surprisingly OppAIV, were targeted to the spirochetal surface. Mutagenesis of the OspA N-terminus defined less than five N-terminal amino acids as the minimal secretion-facilitating signal. With the exception of negative charges, which can act as partial subsurface retention signals in certain peptide contexts, lipoprotein secretion occurs independent of N-terminal sequence. Together, these data indicate that Borrelia lipoproteins are targeted to the bacterial surface by default, but can be retained in the periplasm by sequence-specific signals. Description: Molecular and Cell Biology II Room G027 Dykes 1:54 PM Abstract 183 URI: http://hdl.handle.net/2271/129 Files in this item: 1
01_54_Schulze_183.ppt (1.803Mb) -
Champion, Thomas (July 6, 2006)[more][less]
Abstract: Acute pancreatitis is an inflammatory disorder of the pancreas. Most progress in research of its pathogenesis was obtained from experimental models in rats and mice. In the initial onset, trypsinogen activation plays a critical role. Proteomic studies of exocrine pancreatic tissue revealed differences in trypsinogen isoform patterns of various mouse strains. In the present study, we asked what is the extent of trypsinogen activation, if any, in caerulein-hyperstimulated pancreatic acini prepared from four different mouse strains. The strains used were CD1 and NMRI, which are vigorously outbred, and C57BL/6 and FVB, which are inbred. The pancreatic acini were isolated from the pancreata using collagenase digestion. Acini were stimulated with 0.1µM caerulein. Trypsin activity was fluorometrically measured with the fluorogenic substrate BZiPAR (Molecular Probes/USA). Protein concentration in acini homogenates was estimated by Bradford. Cell injury in acini suspensions was quantified based on measurement of lactate dehydrogenase (LDH) activity with the Cytotoxicity Detection Kit (Roche/Germany). C57BL/6 showed four to five times higher trypsin activation than the other three strains, although initial trypsinogen content was not statistically different. Cell injury measured by LDH release, does not correlate with the levels of trypsin activity. Higher trypsin activity in caerulein hyperstimulated acini of C57BL/6 is accompanied by an increased Cathepsin B activitiy. Different levels of trypsinogen activation in various strains might be caused by different quantities of various trypsinogen isoforms in mouse strains, different activities of trypsinogen-activation enzymes (such as Cathepsin B), and/or various levels of trypsin inhibitors. Future studies will focus on these questions. Description: Molecular & Cell Biology III Room G027 Dykes 3:00 PM Abstract 187 URI: http://hdl.handle.net/2271/176 Files in this item: 1
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Ammar, Chad (July 5, 2006)[more][less]
Abstract: Thromboxane A2 (TXA2) is an arachidonic acid metabolite that is released during tissue trauma and elicits platelet aggregation and vascular smooth muscle contraction. Previous research has shown that TXA2 stimulates pulmonary and cardiac vagal afferent neurons. In addition, it has also been shown that TXA2 receptor (TP)mRNA is expressed in a sub-population of neurons in the nodose ganglia. This study was designed to further characterize the afferent vagal neurons that express TXA2 receptor gene transcript. We hypothesize that TP is expressed in nociceptive (pain-sensing) neurons. To test this, multiplex single-cell RT-PCR was employed on cultured nodose ganglion neurons from the rabbit. Primers for neurofilament medium (NFM), TP, and the capsaicin receptor (TRPV1) were added to the RT-PCR reaction. NFM was used as a positive neuronal marker, while the presence of TRPV1 was used to distinguish nociceptive from non-nociceptive neurons. Ninety-three cells were isolated from culture and RT-PCR was carried out on individual cells. Of the 79 NFM positive cells, 55 were TRPV1 positive and 20 were TP positive. Of the 20 TP positive cells, 13 (65%) were TRPV1 positive. Therefore, we conclude that the presence of TP mRNA in a subset of nociceptive neurons allows for the possibility that TXA2 may contribute to the onset of pain or activation of reflexes during myocardial ischemia by stimulating or modulating vagal afferent neurons. Description: Cardiovascular Biology Room G025 Dykes 1:42 PM Abstract 149 URI: http://hdl.handle.net/2271/160 Files in this item: 1
01_42_Ammar_149.ppt (2.803Mb) -
Branstetter, Jo Ellen (May 19, 2006)[more][less]
Abstract: Purpose: To explore the impact of childhood chronic illness/disability on family communication patterns. Method: Sixty interviews (30 parent/sibling dyads, selected) done upon completion of an intervention study (N = 252) provided data for this report; with semi-structured interview guides, parents and siblings were interviewed separately. Transcriptions of the interviews were analyzed using qualitative methods. Line by line analysis was used to identify codes, categories, and themes reflecting the content, significance, and impact of chronic illness, and an intervention on family communication patterns.Findings: Four themes emerged from the data: (1) Giving Voice: A process of positive movement in communication through which the internal self gains voice to express feelings, wants, needs, concerns, fears, and questions; (2) Communication: A Reflection of Relationships and Roles: A reflection of the dependent nature of roles and relationships experienced internally, manifested externally, and reflected in individual and family communication; (3) Staying Connected: A dynamic process of valuing communication, remaining available for communication and regulating the content and quality of communication to strengthen family adaptation and cohesion; and (4) Struggling for Normalcy: A process of problem-solving that culminated in shared meaning of the illness/disability experience. A conceptual model was developed to illustrate the interrelationships among the themes. Implications/Conclusions: Findings may be used by health care providers to strengthen communication patterns, adaptation, and cohesion in families of children with chronic illness/disability. Description: Cinical Studies I Room G026 Dykes 9:32 AM Abstract 110 URI: http://hdl.handle.net/2271/78 Files in this item: 1
09_32_Branstetter_110.ppt (566.2Kb) -
McIntire, Kevin (June 30, 2006)[more][less]
Abstract: Trunk rotational strength asymmetry has been suggested in adolescents with idiopathic scoliosis (IS). This finding has yet to be confirmed against a group of healthy adolescents. This study compares the isometric trunk rotational strength, in the neutral position, of a group of healthy adolescent females, n=10, mean age 14.3 years (± 2.4) with that of a group of female adolescents with IS, n=13 mean age 13.4 (± 1.4) years, mean Cobb 28° (±8°, range 19°-41°). Each participant’s isometric trunk rotational strength was tested using a reliable procedure. Torque values were normalized to lean body weight (LBW). AIS individuals’ torque values were also normalized to their primary curve direction so that rotational directions were in the direction of the convexity or concavity of the primary curve. The healthy group of adolescents had an average normalized torque of 0.89 Nm/Kg (±0.29, range 0.41-1.41) to the right and 0.87 Nm/Kg (±.23, range 0.56-1.27) to the left, not significant (p<0.46). The scoliosis group had an average of 0.92 Nm/Kg (±.2, range 0.33-1.25) towards the convexity of the curve and 0.84 Nm/Kg (±.2, range 0.35-1.03) towards the concavity, not significant (p<0.15). There were also no differences between the healthy group and scoliosis group. These results may need to be further confirmed in a larger sample size. Description: Musculoskeletal Room G027 Dykes 10:12 AM Abstract 215 URI: http://hdl.handle.net/2271/145 Files in this item: 1
10_12_McIntire_215.ppt (1.000Mb) -
Stucky, Chee-Chee (July 5, 2006)[more][less]
Abstract: Background: While the prevalence of obesity continues to increase in our society, outdated resting energy expenditure (REE) prediction equations may over-predict energy requirements in obese patients. Therefore, many physicians now advocate the use of the Cunningham equation (CE) based on fat free mass (FFM). Accurate feeding is essential since overfeeding has been demonstrated to adversely affect outcomes. Objectives: The first objective was to compare REE calculated by prediction equations to the measured REE in obese trauma and burn patients. Our hypothesis was an equation using FFM would give a more accurate prediction. The second objective was to consider the effect of a commonly used injury factor on the predicted REE. Methods: A retrospective chart review was performed on 33 patients. REE was measured using indirect calorimetry and compared with the Harris-Benedict Equation (HBE), CE and an equation using type II diabetes as a factor (DE). Statistical analyses used were paired t-test, ±95% confidence interval, and the Bland-Altman method. Results: Measured average REE in trauma and burn patients was 21.37±5.26 and 21.81±3.35 kcal/kg-day, respectively. HBE under-predicted REE in trauma by 11.98±21.28% and in burn by 13.05±21.42%. CE under-predicted REE in trauma by 31.26±26.05% and in burn by 31.15±25.22%. DE under-predicted REE in trauma by 15.25±23.32% and in burn by 16.63±18.84%. Using a standard injury factor of 1.2, CE under-estimated by 9.38±21.71% in trauma and 9.29±21.02% in burn patients. HBE over-estimated by 6.68±17.73% in trauma and 5.79±17.85% in burn patients. DE over-estimated by 3.96±19.43% in trauma and 2.81±15.37% in burn patients. Conclusions: The measured average REE is significantly less than current guidelines of 25-27 kcal/kg-day. This suggests that a hypocaloric regimen may be worth considering for ICU individuals possibly using the CE. Also, if an injury factor of 20% is incorporated in either the HBE or DE, patients may be given too many kilocalories possibly leading to worsening outcomes. Description: Clinical Studies II Room G026 Dykes 1:54 PM Abstract 144 URI: http://hdl.handle.net/2271/165 Files in this item: 1
01_54_Stucky_144.ppt (1.560Mb) -
Crane, Jennifer (June 30, 2006)[more][less]
Abstract: Cranial neural crest cells are a multipotent migratory cell population that gives rise to the majority of the developing head and face, including bones, cartilage, connective tissue, cranial nerves and pigment cells. During embryonic development, a population of cranial neural crest cells migrates toward the developing frontonasal prominence (FNP) and gives rise to specific mid-facial structures such as the nasal, premaxillary and maxillary bones. The ectoderm of the FNP is known to be essential for neural crest cell viability and differentiation. Although many genes are known to be involved in the patterning of this region, FGF8 signaling has been implicated in playing a particularly critical role. To examine the role of FGF8 signaling in the developing mid-facial region, we conditionally inactivated the Fgf8 gene specifically in the frontonasal ectoderm, using the Cre-loxP recombination system and an Ap2a promoter. Tissue specific inactivation was confirmed by the loss of Fgf8 expression in the FNP and not in the apical ectodermal ridge of the limbs. Embryonic day (E)10.5 embryos display transient crania bifida (delayed closure of the forebrain neuropore), ring-shaped FNP and an absence medial and lateral nasal pits. In addition mutant embryos also lack the maxillary component of the first branchial arch and have a reduced manibular prominence. Skeletal preparations of E14.5 embryos demonstrate a tubular shaped hypoplastic nasal cartilage, absence of distal lower and upper jaw components, including the nasal bones which persist through to E17.5. In addition, E17.5 embryos lacked multiple bones of the skull vault. Only the frontal bones were present and these were abnormal in shape and did not project medially. We are currently investigating the effects of the conditional inactivation of Fgf8 on the migration and viabililty of cranial neural crest cells as part of the mechanistic origins of the craniofacial anomalies observed. Collectively, these results demonstrate a tissue specific requirement for FGF8 signaling in the frontonasal region as a critical component of normal craniofacial morphogenesis. Description: Developmental Biology Room G026 Dykes 10:12 AM Abstract 146 URI: http://hdl.handle.net/2271/139 Files in this item: 1
10_12_Crane_146.ppt (1.743Mb) -
Griffin, Darcy (May 22, 2006)[more][less]
Abstract: The existence of monosynaptic connections between primary motor cortex neurons and motoneurons is well established (Lemon and Porter, 1993). These Corticomotor (CM) neurons and the signals they carry are integral to understanding mechanisms underlying movement execution. Such a direct synaptic connection is assumed to drive motoneuron activity and ultimately muscle activity during skilled movements. If this is the case, the activity of a CM cell would be expected to covary closely with that of its target muscles during voluntary movement. To test this hypothesis, the presence of postspike facilitation (PSpF) in spike-triggered averages of electromyographic (EMG) activity was used to identify cortical neurons with excitatory synaptic linkages to motoneurons. Cell-target muscle covariation was quantified by plotting the average firing rate of each CM cell against the EMG activity of each of its facilitated target muscles. The Spearman’s Correlation Coefficient, obtained from the resulting scatter plot, was used to quantify the covariation of CM cell and target muscle activity. The majority of cell-target muscle pairs covaried positively during the task (83.5%). The strength of covariation between the activity of CM cell-target muscle pairs was related to 1) the magnitude of PSpF (r = .26, P < .01) and 2) mean CM cell firing rate (r = .22, P < .01). Our data establishes the existence of correlation between CM cell and target muscle activity and for the first time demonstrates that the strength of CM cell-target muscle correlation varies as a function of the strength of the CM synaptic linkage. Description: Neuroscience I Room 1028 Dykes 8:32 AM Abstract 132 URI: http://hdl.handle.net/2271/85 Files in this item: 1
SRF2006_Covariation.ppt (8.143Mb) -
Swink, Jason (May 19, 2006)[more][less]
Abstract: The repair of injuries to tendons, ligaments, and other connective tissue is performed in hospitals every day. The standard method of tendon repair involves bringing the edges of the severed tendon in contact and suturing them together. Generally, both a core stitch and an epitenon stitch are used. The core stitch provides strength and the epitenon holds the edges in very close proximity, to facilitate healing. Currently, the stitches are performed by hand by a surgeon, and perform very well. This goal of this project was to design a tool to automatically suture, in order to speed up the process, and to provide a high degree of reproducibility and resolution. RESULTS: A machine was designed, using the Autodesk Inventor software for drafting. The initial design accounted for only an epitenon stitch. Preliminary work was performed on construction of a scaled-up model of the machine. Although a testable model has not been completed, the major mechanical impediments have been solved. CONCLUSION: A working model can be constructed from the completed design. It will perform with great fidelity and speed the tiny stitches required to repair a severed flexor tendon. More work is required to discover the ideal materials for all parts, as well as to build a testable model. Once a model is available, a study can be performed to compare repaired tendon strength with a tendon repaired by hand. Description: Clinical Studies I Room G026 Dykes 8:56 AM Abstract 118 URI: http://hdl.handle.net/2271/76 Files in this item: 1
08_56_Swink_118.ppt (1.468Mb) -
Smith, Casey (June 30, 2006)[more][less]
Abstract: Reliable and comparable biomechanical testing of total ankle replacement (TAR) systems can only be accomplished with an accurate standardized simulation of ankle mechanics. Information about the kinetics and forces acting on the tibiotalar joint is vital to developing accurate and comparable simulations. Current simulation models rely on extrapolation of 2D force plate information or on mathematical model predictions to approximate the forces at this joint. The main goal of this project was to design an implantable force sensor to isolate and directly measure the axial compressive force acting on the tibiotalar joint during the gait cycle. The ultra high molecular weight polyethylene (UHMWPE) mobile bearing of the Scandinavian Total Ankle Replacement (STAR) was chosen for modification due to the design’s inherent isolation of the axial compressive force. Initial design has focused on creating a radiopaque fluid force sensor that can give reliable and repeatable force measurements at the tibiotalar joint after implantation. The force sensor can be monitored in vivo using fluoroscopic video methods allowing force measurements during weight bearing movements of the ankle joint. Using this data, 2D pattern recognition techniques can be used to recreate a 3D model of the TAR components and model the ankle kinematics corresponding to the compressive force information. Design is currently in the preliminary, feasibility testing stages. Initial tests support the feasibility of the design, but additional design modification and feasibility tesing are required to optimize and validate the design. Description: Musculoskeletal Room G027 Dykes 11:24 AM Abstract 172 URI: http://hdl.handle.net/2271/149 Files in this item: 1
11_24_Smith_172.ppt (14.66Mb) -
Hansen, Philip (July 7, 2006)[more][less]
Abstract: Through the use of Schistosoma mansoni antigens we attempted to develop a non-invasive assay that would diagnose an infection of intestinal schistosomiasis. We isolated parts of the Schistosoma mansoni parasite shed during its infestation of the host (e.g. skin, eggs, tegument, circulating cathoiodic antigen [CCA], circulating aniodic antigen [CAA]) from the urine of infected individuals to develop mono-clonal antibodies against the parasite. The antibodies would be used in dipstick assays to detect the presence of S. mansoni antigens in the urine of infected people. The assay can be a valuable tool in field for the diagnoses of schistosomiasis without the need for bulky lab equipment. Quick, sensitive and easy to use, the dipstick assay requires no formal training in its application. Description: Neuroscience IV Room 1028 Dykes 3:00 PM Abstract 208 URI: http://hdl.handle.net/2271/178 Files in this item: 1
03_00_Hansen_208.ppt (548.3Kb) -
Veeh, Jessica (July 6, 2006)[more][less]
Abstract: Objective: Identification of the key transcription factors that regulate the expression of human TIMM8A gene. Background: TIMM8A belongs to a family of evolutionary conserved proteins located in the mitochondrial space involved in mediating import and insertion of hydrophobic membrane proteins into the mitochondrial inner membrane. The purpose of this study was to look at the promoter sequence of the TIMM8A gene and determine which transcription factors play a vital role in the successful transcription of the TIMM8A gene. Methods: Using the promoter region of the TIMM8A gene, gene reporter constructs with serial deletions and site-directed mutagenesis of the promoter region were developed and amplified via PCR. The PCR constructs were then ligated to the pGL3-basic vector and transformated to competent cells for growth. Plasmids were isolated via minipreps and proper insertion verified by restriction digestion and gel electrophoresis. The plasmids were then transfected to HeLa S3 and A204 cells and luciferase activity was recorded. Results: Luciferase showed a major decrease in activity between constructs 7 (-101) and 8 (-29) indicating that construct 7 contains the binding site(s) for the transcription factor(s) regulating the expression of TIMM8A but construct 8 lacks this(these) factor(s). In fact, binding sites for NRF-1 and Sp1 are in the promoter region encompassed by construct 7. Conclusions: We obtained preliminary results indicating that NRF-1 and Sp1 are the major transcription factors involved in the regulation of human TIMM8A expression. New constructs and other experiments (EMSAs, ChIP…) are necessary to precisely identify the role of these factors. Additional constructs were developed around the area of interest. Description: Genetics Room G026 Dykes 3:48 PM Abstract 186 URI: http://hdl.handle.net/2271/172 Files in this item: 1
03_48_Veeh_186.ppt (675.8Kb) -
Fried, Kristian (June 29, 2006)[more][less]
Abstract: Although the perception of dioxins is predominantly negative, they have also been shown to exert beneficial effects in animal models, such as immunostimulation, reduced cancer rates and prolongation of life at sufficiently low (hormetic) doses. Furthermore, some effects at supra-hormetic doses can be considered desirable under certain conditions. Lowering of body weight or increased insulin sensitivity could contribute to the quest for treating obesity or diabetes mellitus type II. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) binds readily to the aryl hydrocarbon receptor (AhR), and, thereby exerts many of its effects. The binding of potential drug candidates to the AhR, however, is often considered detrimental. The expected subsequent induction of CYP1A1 activity is still associated with the metabolic activation of potential carcinogens despite naturally occurring AhR agonists in food. Therefore, a separation of AhR interaction and downstream effects could lead to the exploitation of the beneficial effects of dioxins. A competitive displacement assay was applied to quantitate the binding affinity of the TCDD analog 2,3,7,8-tetrachlorophenothiazine (TCPT) to the AhR. It has been reported previously that the ability of TCPT to induce CYP1A1 activity is 370-times lower than that of TCDD. This binding assay, however, revealed that the Ki of TCPT is 0.85 nM, as compared to a Kd of 0.37 nM for TCDD, i.e. the affinity of TCPT to the AhR is less than three times lower than that of TCDD. Therefore, the high affinity of TCPT to the AhR combined with its much lower potency regarding CYP1A1 induction are promising properties for drug development. Description: Molecular and Cell Biology II Room G027 Dykes 1:30 PM Abstract 109 URI: http://hdl.handle.net/2271/127 Files in this item: 1
01_30_Fried_109.ppt (904.1Kb) -
Johnson, Megan S (June 30, 2006)[more][less]
Abstract: The perpetual state of hyperglycemia existing in diabetes can permanently damage peripheral nerves, resulting in diabetic neuropathy (DN). The most common long-term complication of diabetes, DN causes reductions in intraepidermal nerve fiber (IENF) density that are extensively reported in humans and diabetic animal models. Currently, most studies focus on overall fiber density using PGP9.5, a marker of all epidermal fibers, in part because visualizing markers of fiber subtypes is technically problematic. However, neuronal subpopulations can be differentially vulnerable to settings of nerve injury or disease, perhaps accounting for different sensory symptoms associated with each condition. This study was undertaken to assess whether diabetes differentially affects nerve fiber subtypes, in particular peptidergic and nonpeptidergic subpopulations. To address the inherent difficulties associated with visualizing different subpopulations at the epidermal level, we used transgenic mice expressing green fluorescent protein (GFP) from the MrgD gene promoter, the product of which is expressed only in nonpeptidergic neurons innervating the skin. Diabetes was induced in 8-week-old MrgD mice by intraperitoneal injection of streptozotocin. After 4 weeks, control and diabetic mice were sacrificed and their hindpaw footpads removed and fixed in Zamboni’s fixative. Nonpeptidergic innervation was quantified in 30μm sections by counting the number of GFP-fluorescent IENF. Using GFP fluorescence in conjunction with PGP9.5 immunostaining, peptidergic IENF density was extrapolated. Results from this study will allow us to characterize the contribution of these different subpopulations to the overall fiber loss seen in DN as well as deepen our understanding of their functional roles in nociception. Description: Neuroscience III Room 1028 Dykes 1:42 PM Abstract 202 URI: http://hdl.handle.net/2271/156 Files in this item: 1
01_42_Johnson_202.ppt (16.09Mb) -
McGinnis, Lynda (June 30, 2006)[more][less]
Abstract: Multiple signaling pathways are initiated during egg activation and fertilization in mammals. In this project we sought to determine the dynamics of active src family kinases (SFK). The relative distribution of SFK potential target substrates was studied by localizing tyrosine phosphorylated proteins (P-Tyr) in mouse eggs undergoing fertilization during progression from meiosis (MII) through to extrusion of the second polar body. Female CF1 mice were superovulated with PMSG and hCG and mated to B6D2F1 males and oviductal oocytes were collected 14-16 hours post-hCG and fixed in microtubule stabilization buffer with 2% formalin. Eggs were labeled for indirect immunofluoresence detection with appropriate primary antibodies against activated SFK or P-Tyr and all samples were counter stained for detection of f-actin (phalloidin), microtubules (alpha-tubulin) and chromatin (Hoechst). Activated SFK labeling was evenly distributed throughout the cytoplasm of eggs from MII through second polar body extrusion with no apparent changes in distribution during the completion of meiosis. In contrast, P-Tyr labeled proteins were enriched in the egg cortex and appeared to be polarized to the region overlying the meiotic spindle in most oocytes. There was pronounced labeling of activated SFK to the MII spindle that persisted in mid-body microtubules during polar body extrusion, while P-Tyr was restricted to a small region of the spindle poles. These findings suggest that active SFKs are sequestered within the meiotic spindle components of mouse oocytes and further studies are ongoing to determine the role of SFKs in mouse fertilization and early embryo development. Description: Developmental Biology Room G026 Dykes 10:24 AM Abstract 199 URI: http://hdl.handle.net/2271/140 Files in this item: 1
10_24_McGinnis_199.ppt (891.9Kb) -
Stephanopoulos, Ourania (June 30, 2006)[more][less]
Abstract: Background: Epileptic patients take multiple antiepileptic drugs (AEDs) which have been shown to increase the risk of bone fractures. Few studies have investigated the affects of AED monotherapy. Objective: To assess the risk of fracture of epilepsy patients taking Carbamazepine (Tegretol) monotherapy via bone mineral density as measured by dual energy X-ray absorptiometry (DEXA) scan T-scores of femoral necks and spine. Methods: A retrospective chart review was conducted for 123 epileptic patients, between the ages of 12-80, at the Via-Christi Comprehensive Epilepsy Center in Wichita, Kansas who were on antiepileptic medications for at least two years, and had undergone a DEXA bone scan. Results: Of 123 patients 5 were found to be on Carbamazepine monotherapy. Of these 5 patients there were 4 females and 1 male with an average age of 42 years and an average duration on Carbamazepine therapy of 5.7 years. The average DEXA scan T score was noted to be in the good bone health range with a value of -0.07. The lowest DEXA T score was attributed to the single male and found to be in the osteopenic range with a value of -1.2. The single male case did not have the longest duration of carbamazepine therapy though he was the only patient among the 5 to be non-ambulatory. A negative correlation was found between duration on carbamazepine therapy and DEXA T-score. Patients taking carbamazepine for greater than 9 years developed osteopenia. Conclusions: Overall the longer patients were taking Carbamazepine (Tegretol) the lower their DEXA femoral neck and spine T scores were suggesting that carbamazepine may increase the risk of bone fractures. The male patient case had the lowest T-score, but not the longest duration of carbamazepine therapy, suggesting that risk of fracture and bone mineral density have multiple contributing factors including the ability to ambulate and hormonal effects. Further investigation with a larger sample size is warranted to better assess these contributing factors. Description: Musculoskeletal Room G027 Dykes 10:24 AM Abstract 176 URI: http://hdl.handle.net/2271/146 Files in this item: 1
10_24_Stephanopoulos_176.ppt (1.073Mb) -
Leiker, Tona (June 29, 2006)[more][less]
Abstract: The turnover rate of certified nursing assistants (CNAs) within the nursing home setting is greater than 100% in Kansas. Understanding turnover is vital to the recruitment and retention of CNAs. The purpose of this study was to understand the meaning of CNAs' experiences in a nursing home setting using the hermeneutic phenomenological research method. Student researchers completed observations and interviews with four CNAs in one nursing home over a 3-month period. Using an iterative reduction approach, hermeneutical interpretation of the data was conducted through thematic analysis and participant other dialogue. Findings revealed that CNAs constantly strived to balance a dynamic tension between multiple opposing forces. The metaphor, balancing dynamic tension, unified opposing forces in two thematic categories: Tension Between Conflicting Cultures and Tension Between Job and Self. CNAs are expected to balance industry expectations of efficiency with the patience necessary to provide individualized care, to discern between normal and unusual variations in the residents' well-being, and to maintain a sense of community while attempting to balance discrepant and shifting levels of valuing and voice afforded them within the nursing home. When experiencing tension between job and self, the CNAs job required both physical and emotional strength, self protection from injury, and maintenance of connections with residents. These findings offered insights into CAN experiences such as feelings of loss and the need for protection. Support for CNAs may be provided by listening and responding respectfully, recognizing CNAs as expert in knowing, valuing, caring, and increasing CNAs involvement in planning resident care. Description: Public Health & Outcome II Room G025 10:48 AM Abstract 131 URI: http://hdl.handle.net/2271/130 Files in this item: 1
10_48_Leiker_131.ppt (2.418Mb)
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