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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Characterization of Zic2 as an Oncoprotein in Prostate Cancer

Davis, Keira C. 22 May 2017 (has links)
The field of prostate cancer research is in need of biological markers that predict which cancers do not need treatment, those that can be treated successfully with a localized treatment and more specific cases in which patients are likely to have an aggressive form of cancer that will require more aggressive surgical and chemotherapeutic treatments. ZIC2 is one of five members of a family of proteins that play critical roles in neural crest and mesoderm growth in normal embryonic brain development and in the adult cerebellum of vertebrates. Found throughout the animal kingdom, ZIC1-5 genes encode five distinct ZIC proteins containing five highly conserved C2H2-type zinc finger motifs whose structural integrity is important in carrying out its function as a transcription factor. We hypothesize that ZIC2 has functional significance at the molecular and cellular levels in the initiation of prostate adenocarcinoma (PRAD) and the progression to metastatic and/or castration resistant prostate cancer (CRPC). Bioinformatic predictions suggest that the function of ZIC2 is regulated by post-translational modifications, such as phosphorylation, ubiquitination and sumoylation. This proposal further outlines the research hypothesis for investigating the role of ZIC2 in prostate cancer progression and the effects of the post-translational modification, ubiquitination, on the loss or gain of function of ZIC2.
12

Directed Nickel-Catalyzed Allyl Methylation of Unactivated Alkenes Utilizing a Monodentate L-Type Directing Group

Gallagher, Timothy 01 January 2019 (has links)
Transition-metal-catalyzed cross-coupling reactions are reliable tools for forging C–C bonds. The Engle Lab has previously pioneered the intermolecular difunctionalization of unactivated alkenes facilitated by nickel catalysis, where regioselectivity is controlled through the use of a bidentate directing group. A limitation of existing methods is that allyl groups have not yet been successfully incorporated, as the electrophile scope has been limited to alkyl and aryl species. Fundamentally, C–C p-bonds have served as key building blocks for the assembly of complex molecules, and the ability to introduce allyl moieties in a controlled manner enables diverse, downstream functionalization in multi-step synthesis. This work focuses on the use of diverse azaheterocycle directing groups connected to non-conjugated alkenes. Through the use of nickel catalysis, we have been able to successfully introduce and preserve allyl and cinnamyl species at the g-position and alkyl zinc nucleophiles at the b-position with high yield under mild conditions. This novel, 1,2-allylalkylation can accommodate a vast array of substituents with different electronic and steric properties (>20 examples). Our efforts have shifted to exploring different monodentate directing groups and to conduct mechanistic studies to shed light on the catalytic cycle. Interestingly, electron-rich electrophiles provide nearly quantitative NMR and isolated yields, whereas electron-poor electrophiles lead to lower yields. We report a competition experiment to further elucidate this mechanism. While isolated yields were generally higher for electron-rich groups, a competition between p-OMe and p-CF3 electrophiles led to preferential incorporation of the trifluoromethyl-substituted coupling partner, which supports oxidative addition as the product-determining step.
13

EFFECTIVENESS OF A PHYSICAL ACTIVITY ENHANCING PROGRAM FOR USE DURING INDOOR RECESS

Blase, Cassandra M. 01 January 2018 (has links)
Purpose: The purpose of this study was to determine if a novel physical activity intervention game (Bingocize®) designed for use in confined spaces and modified to include age appropriate activities would increase the time spent engaged in physical activity (PA) during indoor recess. Methods: Fifty-two third grade children wore triaxial accelerometers during three different recess conditions. The recess conditions included: “typical” indoor recess (TIR), indoor recess with children engaged in Bingocize® (IRB), and “typical” outdoor recess (TOR). Results: There were significant (p < 0.05) differences among the recess conditions for the time spent in sedentary, light, moderate-to-vigorous physical activity (MVPA) intensity categories, as well as PA counts, and steps. During IRB, TIR, and TOR the subject were sedentary 42.4% (±0.10), 71.9%(±0.10), and 17.5% (±0.10) of the recess time, respectively. During IRB, TIR and TOR the subjects spent 43.4%(±0.10), 18.5%(±0.10), and 74.2%(±0.12) engaged in MVPA, respectively. Conclusions: These results indicate that Bingocize® promotes increased PA during times when inclement weather necessitates indoor recess and larger space requirements for activity are not available.
14

Lorcaserin as a potential opioid-sparing adjunct

Lippold, Kumiko M 01 January 2018 (has links)
Opioids, such as oxycodone, morphine, and fentanyl, are commonly used medications in the treatment of moderate to severe pain. In spite of their efficacious analgesic properties, their increased prescribing rates by physicians and inherent abuse-related effects have led to the ongoing opioid epidemic. Their clinical utility is limited by the risk of adverse dose-dependent side effects, such as constipation and respiratory depression, and the development of tolerance and dependence. Opioid-sparing adjunctive therapies are sought to address these issues by reducing the dose of opioid needed to achieve analgesia through alternative non-opioidergic mechanisms and as a result, reduce the incidence of the previously mentioned side effects. Serotonin type-2C receptor agonists have demonstrated antinociceptive efficacy in preclinical models of chronic pain. Lorcaserin is a selective 5-HT2C receptor agonist and was reported to attenuate the abuse-related effects of oxycodone. The antinociceptive properties of 5-HT2C receptor agonists and their potential to alter the abuse-related effects of commonly abused drugs suggest that lorcaserin may be a potential opioid-sparing therapeutic. The goal of these studies was to evaluate the utility of lorcaserin, in combination with opioids, in a preclinical model of acute pain. Based on previous studies demonstrating the antinociceptive activity of 5-HT2C agonists, the hypotheses for these studies were that lorcaserin would increase the acute antinociceptive effects of opioids and would attenuate the development of tolerance associated with chronic opioid consumption. The results demonstrate that the acute antinociceptive effects and the time-course of activity of opioids were enhanced by doses of lorcaserin. These effects were mediated through activation of the 5-HT2C receptor and were not blocked by administration of naloxone. Additionally, the acute effects of lorcaserin to increase opioid potency and time course was not mediated through changes in opioid distribution in the blood or central tissues. Opioid tolerance was evaluated in vivo, and tolerance was developed using two methods of treatment: an acute (single dose administration) model of tolerance and a multiple-injection model. Testing the effect of lorcaserin in these models was important because current research suggests that the mechanisms that underlie both models of tolerance are distinct from one another. The results demonstrate that lorcaserin significantly blocked the development of acute tolerance in the whole animal and on a single cell level in dorsal root ganglion cell cultures. In the multiple-day tolerance model, lorcaserin partially attenuated the development of opioid antinociceptive tolerance. Chronic administration of an opioid is associated with desensitization of the MOR, and the effect of lorcaserin on opioid tolerance may be mediated through changes in MOR functional activity. Upon further investigation using agonist-stimulated [35S]GTPyS, the results showed that lorcaserin altered basal binding of [35S]GTPyS but not agonist-stimulated binding in mice that received chronic opioid treatment. These data suggest that the effect of lorcaserin on opioid tolerance, in the multiple-injection model, is not mediated through changes in MOR functional activity. Collectively, the tolerance studies suggest that the effect of 5-HT2C receptor activation by lorcaserin has differential effects on the stages of opioid tolerances and further supports the notion that the mechanisms that underlie the stages of opioid tolerance are distinct. Given the efficacy of lorcaserin to increase the acute antinociceptive effects of opioids and its ability to impair the development of opioid tolerance, collectively, these data suggest that lorcaserin may be a useful opioid-sparing adjunctive therapy.
15

LPS-Induced iNOS mRNA and the Pro-Apoptotic Signaling Pathway in Leukocytes of Fit and Unfit Males

Zuniga, Tiffany M 01 January 2018 (has links)
Overexpression of the enzyme iNOS induces apoptotic cellular death by increasing indices of pro-inflammation and oxidative stress. Aerobic physical activity has been known to have anti- inflammatory benefits and reduce oxidative stress. Purpose: Therefore, this study aimed to examine the impact of aerobic fitness on LPS-induced iNOS mRNA expression and the relationship of this expression with indices of oxidative stress, pro-inflammation and apoptosis in isolated leukocytes. Methods: Whole blood samples from aerobically fit and unfit males were stimulated with and without LPS. Thereafter, iNOS mRNA expression and MDA, TNF-α and p53 concentrations were analyzed. Results: iNOS mRNA expression levels following LPS stimulation were not increased in both groups, and correlational analyses were not consistent with mechanistic predictions. Discussion: Numerous factors including timing of sample quantification, the high level of health of the subject population, and alternative intracellular mechanisms impacting biomarkers analyzed, may have influenced leukocyte iNOS mRNA expression levels.
16

Naturvetenskap och Bilderböcker : Naturvetenskaplig Begreppsbildning och Grundläggande Naturvetenskapliga Matoder / Science and Picture Books : Science Concepts and Basic Science Skills

Skanse, Maria January 2010 (has links)
Preschool has a long tradition of using picture books, both as entertainment and as a resource for educational activities. In science there are two main application areas. The first one is science concepts and the second is to teach basic science process skills. These skills, observing, communicating, inferring, classifying, measuring and predicting reflects the methods used by scientists. Picture books potential to put science concepts and activities that promote the use of science process skills in a meaningful context, recommends using picture books for this purpose. However there is an issue about finding an appropriate selection of books, mainly when used for science concept formation. This study focuses on fictional picture books and discusses potentials and limitations of using them as a resource for preschool science. / I förskolan finns en lång tradition av att använda bilderböcker, både som underhållning och underlag för pedagogiska aktiviteter. Inom det naturvetenskapliga området finns två huvudsakliga användningsområden. Det första är naturvetenskaplig begreppsbildning och det andra är att använda bilderboken som utgångspunkt för att lära ut grundläggande naturvetenskapliga förmågor. Dessa förmågor, att observera, kommunicera, dra slutsats, klassificera, mäta och att förutspå, reflekterar det arbetssätt som används av forskare. Bilderbokens möjlighet att sätta naturvetenskapliga begrepp respektive aktiviteter som uppmuntrar barnen att använda naturvetenskapliga metoder i ett för barnen meningsfullt sammanhang, talar för att bilderboken används som utgångspunkt för detta. Ett problem som finns är att det är svårt att ta fram ett lämpligt urval. Detta gäller framförallt när bilderboken används som utgångspunkt för begreppsbildning. Denna studie är fokuserad på ett skönlitterärt urval, och diskuterar de möjligheter och begränsningar som finns med att använda skönlitterära bilderböcker som utgångspunkt för naturvetenskap i förskolan.
17

Caffeine Supplementation and Moderate Intensity Exercise Modulates the Cytotoxic Lymphocyte Subset (CD+8) in NaIve and Tolerant Individuals

Fedor, Elizabeth Ann 01 December 2010 (has links)
The purpose of this investigation was to determine the effects of caffeine supplementation on caffeine tolerant and caffeine naïve individual’s lymphocyte counts, apoptosis and migration levels. In addition, effects of exercise on post-caffeine ingestion lymphocyte counts, apoptosis and migration levels were determined. It was hypothesized that caffeine would alter the immune system cell counts, but that exercise would be able to restore the immune system to homeostasis. Seventeen Western Kentucky University students were tested (males n=7, females n=10; n=7: caffeine tolerant= 200mg or more per day group, n=9: caffeine naïve= 50mg or less per day group). In this double-blind investigation, all participants completed two exercise bouts: 30 min of treadmill running at 60-80% HRR once with a placebo drink before exercise and once with 6 mg/kg body weight of caffeine drink completed in a counterbalanced manner. Blood was taken at rest, 30 min after drink ingestion, immediately post exercise, and 60 min post exercise. Blood was stained with antibody markers (Annexin V to determine apoptotic cell counts, CX3CR1 to determine cell migration, CD4=helper T cells, CD8=cytotoxic T cells, CD19=B cells). Blood was analyzed using flow cytometry. We found that cytotoxic T cells showed significant increases following the caffeinated run in both groups combined (tolerant and naïve, p=0.001) and specifically in the naïve group on the caffeine run (p=.004). We did not see any significant changes in CD4, or CD19 cell counts. There were no significant changes in CD4, CD8 or CD19 cell migration or apoptosis. Our results showed that caffeine supplementation causes an increased effect on cytotoxic T cells counts when combined with exercise, and this effect was greater for the caffeine naïve group. The combined effects of caffeine and exercise may have elevated the plasma catecholamine and cortisol levels which are associated with immune cell function and movement. CD8 cells have a greater density of β-receptors, which are influenced by catecholamine, and may explain the increase in their cell counts compared to CD4 and CD19.
18

Towards an Action Spectrum for Photoentrainment of the <i>Chlamydomonas ReinhardtII</i> Circadian Clock

Gaskill, Christa 01 December 2008 (has links)
No description available.
19

The Effect of Orally Administered Butylated Hydroxytoluene on Herpes Simplex Keratitis

Carson, Donald 01 November 1983 (has links)
Some studies have reported in vitro inactivation of membrane enveloped viruses by Butylated hydroxytoluene (BHT). This study investigates the effect of orally administered BHT on primary infections of Herpes simplex virus (HSV) using rabbit corneas as the assay system. Assigned levels of BHT were incorporated into the diet of New Zealand White rabbits with HSV-1 McKrae strain on the corneal surface of the eyes. The degree of infection was measured by a subjective assay. Rabbits receiving BHT in their diet consistently experienced lower levels of infection. The interpretation of this data is that orally administered BHT can be an effective inhibitor of primary infections by HSV in rabbits.
20

Aqueous Micellar Gels of Multiresponsive Hydrophilic ABA Linear Triblock Copolymers

Woodcock, Jeremiah Wallace 01 December 2011 (has links)
This dissertation presents the synthesis of a series of well-defined multiresponsive hydrophilic ABA linear triblock copolymers and the study of their aqueous micellar gels. By incorporating a small amount of stimuli-responsive groups into thermosensitive outer blocks of ABA triblock copolymers, the lower critical solution temperatures (LCST) of thermosensitive blocks can be modified by external stimuli. Consequently, the sol-gel transition temperatures (Tsol-gel) of their aqueous solutions can be altered. Chapter 1 describes the synthesis and solution behavior of a series of thermo- and light-sensitive triblock copolymers, poly(ethoxytri(ethylene glycol) acrylate-co-o-nitrobenzyl acrylate)-b-poly(ethylene oxide)-b-poly(ethoxytri(ethylene glycol) acrylate-co-o-nitrobenzyl acrylate), with different contents of light-responsive o-nitrobenzyl groups. Aqueous solutions of these block copolymers with a 10.0 wt% concentration exhibited thermo-induced sol-gel transitions. Upon UV irradiation, the hydrophobic o-nitrobenzyl groups were cleaved, resulting in an increase in the LCST and consequently gel-to-sol transitions. The UV-irradiated solutions again underwent temperature-induced sol-gel transitions but at higher temperatures. The change of Tsol-gel was, in general, larger for the copolymer with a higher o-nitrobenzyl content after UV irradiation. Chapter 2 presents the synthesis of thermo- and enzyme-responsive ABA triblock copolymers, poly(ethoxydi(ethylene glycol) acrylate-co-4-((dihydroxyphosphoryl)oxy)butyl acrylate)-b-poly(ethylene oxide)-b-poly(ethoxydi(ethylene glycol) acrylate-co-4-((dihydroxyphosphoryl)oxy)butyl acrylate), and the enzyme-induced formation of thermoreversible micellar gels from their moderately concentrated aqueous solutions at 37 °C. The dephosphorylation by acid phosphatase decreased the LCST of thermosensitive outer blocks from above to below 37 °C. The enzyme-induced gelation of 7.9 wt % aqueous polymer solutions at pH 4.4 was monitored by rheological measurements. The Tsol-gel decreased and the gel strength increased with the increase of reaction time. The gels formed were thermoreversible. Chapter 3 presents the synthesis of two thermo- and pH-sensitive tertiary amine-containing ABA triblock copolymers and the sol-gel transitions of their aqueous solutions with a 10 wt% concentration at different pH values. Chapter 4 describes the use of reversible addition-fragmentation chain transfer (RAFT) polymerization for the synthesis of well-defined thermosensitive polymethacrylates and polyacrylates. Eight chain transfer agents were synthesized. The RAFT polymerizations of alkoxyoligo(ethylene glycol) (meth)acrylates using these chain transfer agents were well controlled, producing well-defined polymers. A summary of this dissertation research and future work are presented in Chapter 5.

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