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Insulin Treatment Attenuates Renal Adam17 And Ace2 Shedding In Akita Diabetic Mice, Esam Said Busah Salem

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Diabetic patients have a 40%-50% lifetime chance of developing chronic kidney disease, which remains one of the leading causes of morbidity and mortality. Alterations within renin angiotensin system balance contribute to the pathogenesis of diabetic kidney disease. Angiotensin converting enzyme 2 (ACE2) has an endogenous renoprotective role due to its ability to form angiotensin (1-7) (Ang 1-7) by degrading angiotensin II (Ang II). We have shown previously that hyperglycemia increases urinary ACE2 and albumin excretion in db/db diabetic mice. The protease, disintegrin and metalloprotease (ADAM) 17, is involved in the shedding of several transmembrane proteins, including ACE2 in vitro. Tissue …

Physical Exercise Training But Not Metformin Attenuates Albuminuria And Shedding Of Ace2 In Type 2 Diabetic Db/Db Mice, Hari Krishna Somineni

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Angiotensin II (Ang II), a potent vasoconstrictor cleaved from Ang I, is responsible for renal damage in diabetes. Angiotensin converting enzyme 2 (ACE2) is highly expressed in the kidney and has been shown to be renoprotective by degrading Ang II to Ang-(1-7). A Disintegrin and Metalloproteinases (ADAMs) were recently identified as an ectodomain sheddases of transmembrane proteins. ADAM17 mediated shedding of renal ACE2 could contribute to the pathogenesis of diabetic nephropathy. In our previous study, rosiglitazone treatment normalized hyperglycemia and improved renal injury by preventing ACE2 shedding. The aim of this study is to test the hypothesis that improved glucose …

Regulation Of The Stability And Cellular Localization Of The Coxsackievirus And Adenovirus Receptor (Car), Ran Yan

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In polarized epithelia, the seven exon isoform of the Coxsackievirus and adenovirus receptor (CAR^Ex7) is a basolateral cell-cell adhesion protein that is inaccessible for viral infection. In contrast, the eight-exon CAR isoform (CAR^Ex8) localizes at the apical surface and mediates adenovirus (AdV) infection. A PDZ-domain containing protein, MAGI-1, interacts with both isoforms of CAR. I hypothesized that each CAR isoform interacts with specific MAGI-1 PDZ domain(s). Co-immunoprecipitation, FRET and binding assays showed that CAR^Ex7 and CAR^Ex8 both interact with MAGI-1-PDZ3 with high affinity. CAR^Ex8 also interacts with MAGI-1-PDZ1. Whereas the CAR^Ex7-PDZ3 …

Bioaccumulation And Neuroinflammation Of Gold Nanoparticles In The Central Nervous System, Fahimeh Fallahi

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Gold nanoparticles (GNPs) possess unique physicochemical properties that may facilitate entry into the central nervous system (CNS) where they may act therapeutically. There is little information on biodistribution or inflammatory effects of GNPs in specific brain regions. Brain Localization and neuroinflammatory response to citrate-capped spherical GNP (10 nm) was determined 24 hours after intravenous (IV) injection in male C57Bl mice. A known inflammogen, lipopolysaccharide (LPS, 2 mg kg-1, SC), was tested as a positive control supplement. Aggregation of GNPs was measured using various Phosphate-Buffered Saline (PBS) concentrations (10, 1, 0.1, 0.01 X) to determine the optimal buffer concentration to maintain …

Elucidating A Role Of Btf And Trap150 In Pre-Mrna Processing And Cell Cycle Progression, Sapna N. Varia

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Transcription of protein-coding genes is coordinated with pre-mRNA processing as well as mRNP assembly and nuclear export in mammalian cells. In this dissertation, I examined the functions of two homologous non-classical serine-arginine-rich (SR) proteins, Btf (BCLAF1) and TRAP150 in these steps of gene regulation. Since Btf and TRAP150 share 39% sequence identity and 66% sequence similarity, I also examined whether Btf and TRAP150 have overlapping or distinct functions in pre-mRNA processing. Using two different reporter loci, I showed in-situ recruitment of Btf and TRAP150 at reporter transcription sites, and I identified both Btf and TRAP150 being associated with a core …

Amp-Activated Protein Kinase Knockdown In Labyrinthine Trophoblast Cells Results In Altered Morphology And Function, Erica Ashton Kayleigh Carey

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The placenta is a transient organ that develops upon initiation of pregnancy and is essential for fetal development and survival. The rodent placenta consists of three layers with predominantly analogous cell types in the human placenta. The labyrinth layer, which lies closest to the fetus, facilitates nutrient and waste exchange between mother and baby. Abnormalities of the placenta may occur as a result of cellular stress and have been associated with the pregnancy-associated disorders, intrauterine growth restriction and placental insufficiency. AMP-activated protein kinase (AMPK) is a master sensor of cellular stress and changes in AMPK expression or activation could be …

C-Bouton Coverage Of Alpha-Motoneurons Following Peripheral Nerve Injury, Esra Salah Shermadou

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Peripheral nerve injuries (PNI) cause alternations in central synapses leading to loss of function. The C-bouton synapses onto a-motoneurons in the ventral horn, and has a role in regulating motor output. Following tibial nerve ligation, the somatic C-bouton coverage is depleted (Alvarez et al., 2011), however, it is unknown what happens following crush type injuries. PNI causes neuroglia activation and proliferation that contribute to synaptic alterations, a response that has not been well-characterized in the ventral horn, where motoneurons are located. Therefore, I hypothesize that glia activation following peripheral nerve injury correlates to the degree of depletion of synaptic coverage …

K-Cl Cotransport: Role Of Kcc3 In Cellular Potassium (K) Homeostasis In Kcc3- Transfected Hek-293 Cells, Nagendra Babu Ravilla

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K-Cl cotransport (KCC) mediated by four protein isoforms, KCC1 to KCC4, plays a significant role in cell volume regulation, and in K and Cl homeostasis. In this study, we demonstrate the importance of KCC3 and its two threonine (T) phosphorylation sites T991 and T1048 in cellular K homeostasis in isogenic human embryonic kidney (HEK-293) cells transfected with KCC3 wild type (WT) or constitutively active double mutant KCC3 (AA) expressed under tetracycline or doxycycline control. In both WT and AA cells, under baseline conditions, the Na-K-2Cl cotransport (NKCC) (55 %- 60 %) was the major contributor of Rb influx followed by …

Reactive Oxygen Modulates B Lymphocyte Function Via The Nfκb/Rel Pathway, Eric J. Romer

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Reactive Oxygen Intermediates (ROI) can significantly affect B Lymphocyte function, but the effects on key signaling pathways and gene expression in activated and non-activated B lymphocytes are largely undefined. This study demonstrates a concentration dependent effect of exogenous hydrogen peroxide on the transcriptional regulation of a 3' regulatory region of the Immunoglobulin heavy chain gene (3'IghRR). Specifically, low μM hydrogen peroxide induces an enhancing effect while higher μM hydrogen peroxide (greater than or equal to 100 μM) is suppressive. The enhancing effects of hydrogen peroxide on 3'IghRR activity are dependent on the NFκB/Rel pathway, and appear to be most prominent …

A Comprehensive Tool And Analytical Pathway For Differential Molecular Profiling And Biomarker Discovery, Claude Curtis Grigsby

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The key requirements to any empirically based study are to: (1) accurately measure and then compare the collected results in determining the result of the hypothesis being tested; and (2) collect a sample representative of the entities being studied. To demonstrate that an informatics tool can be designed that provides spectral registration, spectral and chromatographic alignment, visualization, and comparative analysis for data generated from multiple analytical platforms, e.g., LC-MS and GC-MS, the results and data analysis of five unique sets of experiments using a suite of novel informatics tools are presented. Comprehensive and reproducible sample collection techniques were developed concomitantly …

Simulating Hemodynamics In In Vitro Culture Models: Implications On Nano-Biointeractions, Monita Sharma

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Gold nanoparticles (Au-NPs) have demonstrated great potential in the development of a variety of tools with applications ranging from biomedical to military fields. Consequently, there is increasing concern regarding the toxic potential of these nanomaterials. Biodistribution studies demonstrate clearance of Au-NPs from peripheral circulation and bulk localization primarily in the liver and spleen post- intravenous administration. Deposition of Au-NPs in spleen suggests the potential for direct exposure of immune cells to these foreign materials under relatively static conditions. Although much less, due to the Blood Brain Barrier (BBB), Au-NPs appear to also deposit in the brain, suggesting that the resident …

Chronic Swim Stress Attenuates Endocrine Response And Improves Cardiac Function In Mice Lacking The Angiotensin Ii Type 1a Receptor, Najat Khalifa Almahroug

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Stress is a stimulus that causes an often abrupt but always large change in autonomic activity and hormone secretion. Angiotensin II (AngII) is one of the main neurohormonal mediators that are stimulated by stress. AngII mediates most of its relevant biological effects via AngII type1 receptor (AT1R) activation. Stress increases tissue and circulating levels of Ang II which contributes to stimulation of adrenal AT1R, mediating stressinduced hormone release. Ang II through the activation of AT1R not only elevates blood pressure but also has a patho-physiological relevance in cardiac remodeling. The goal of this study was to assess the influence of …

The Effect Of Hsv-1 Infection On Differentiated And Polarized U937 Cells, Allolo Dreiwish Aldreiwish

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Herpes simplex virus type 1 (HSV-1) challenges the host immune system through several mechanisms (Frey, et al., 2009). In vitro, U937 cells (human macrophage-like precursor cell line) are not susceptible to HSV-1 infection when they are not differentiating (Lopez-Guerrero and Alonso, 1997). Differentiation of these cells resistance can abrogates their resistance to HSV-1 (Tenney and Morahan, 1991). In this study, we examined the effect of HSV-1 infection on differentiated and polarized U937 cells. U937 cells are differentiated to M0 cells.

Then, M0 cells are polarized to distinct phenotypes, M1 or M2. M1 are proinflammatory macrophages while M2 are anti-inflammatory cells. …

The Molecular Genetics Learning Progressions: Revisions And Refinements Based On Empirical Testing In Three 10th Grade Classrooms, Amber Nicole Todd

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In the past few decades, there has been a large push for increasing scientific literacy (AAAS, 1989; AAAS, 1993; Achieve, 2013; NRC, 1996; NRC, 2012), especially in areas that are rapidly advancing, like molecular genetics. Much research has been done on student understandings of molecular genetics and the consensus is that the concepts are difficult both to learn and teach (Fisher, 1992; Horwitz, 1996; Kindfield, 1992; Lewis & Kattmann, 2004; Marbach-Ad & Stavy, 2000; Stewart et al., 2005; Venville & Treagust, 1998; etc.). Two learning progressions in molecular genetics have been produced (Duncan et al., 2009; Roseman et al. 2006), …

Libraries From Libraries Approach To The Synthesis Of Arylidene Oxindoles, Kyle James Knisley

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A libraries from libraries combinatorial chemistry approach was employed to synthesize fluorinated derivatives of both oxindoles and isatins as potential pharmaceuticals or targeting agents for imaging purposes related to cancer or Alzheimer's disease. Synthesis for these fluorinated derivatives are described by routes involving, either: a) N-alkylation of 5-substituted isatins followed by Wolff-Kishner reduction to the corresponding oxindoles and final Knoevenagel condensation with aryl aldehydes, or; b) Wolff-Kishner reduction of the isatins followed by condensation and finishing with the N-alkylation of the aldol products. In specific cases, a click reaction followed the N-alkylation of the aldol products to form the isatin …

Establishment Of A Quiscence Herpes Simplex Type 1 Infection In L929 Fibroblasts And Neuro-2a Cells By A Nucleoside Analogue Acyclovir, Noura Shaklawoon

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Herpes simplex type 1 (HSV-1) quiescent infection was established in L929 cells, murine fibroblasts, and in Neuro-2A (N2A) cells, mouse neuroblastoma, by treating them with the nucleoside analogue acyclovir (ACV) 24 hours before infection. Subsequent release of virus from the non-productive state was accomplished by treating the cells with the histone deacetylase inhibitor trichostatin A (TSA). Treatment of both L929 and N2A cell lines with ACV 24 hours before infection induced protection from HSV-1 cytopathic effect. A quiescent state was confirmed by absence of virus plaques when supernatant fluids from ACV-treated HSV-1 infected cultures were titered on Vero cell monolayers. …

Trace Metals In Sediments On The Continental Margin Of The Northwest Atlantic Ocean, Daniel L. Marsh

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Trace metals in the ocean are derived from natural and anthropogenic sources. Despite increased human impact on the marine environment and biological productivity of continental margins, trace metal studies in marine sediments have focused primarily on near-shore regions. I investigated 22 metals in sediments on the continental margin of the northwest Atlantic Ocean to calculate enrichment factors (EF) relative to upper continental crust and identify spatial variations with distance from shore and depth below the sediment-seawater interface. Metals were well correlated with Al, Fe, organic matter, or CaCO3. No clear trends in metal EFs with distance from shore were evident …

"Characterization Of Red Diamondback Rattlesnake Venom Proteins On Cell Death And Function", Venus Ebrahimian

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Snake venom is composed of many different toxins and protein components such as metalloproteases and phospholipase A2. Together, these proteins cause an up regulation in cell death pathways and disrupt the overall homeostasis of a living cell. The Red Diamondback Rattlesnake is abundantly available and well-known specie and has been used as a source for development of new drugs. It has been mainly used for the purposes of making anti-venom but it has also been therapeutically used for surgical purposes to act as an anti-aggregate. Integrins derived from RDB venom has been used for cancer cell treatment as well. Specifically …

Locating Chelerythrine, An Alkaloid, Within A Cytosolic Environment By Maldi-Tof Mass Spectrometry, Bradley Allen Williams

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The quaternary benzo-phenanthridine alkaloid (QBA) chelerythrine (CET) is a well-known inhibitor of PKC and cancer growth (Herbert et al., 1990). In human lens epithelial cells (HLECs), CET almost completely inhibits the Na+/K+ pump ATPase (NKA) without changes in phosphorylation (Lauf et al. 2013). Protein alignment studies revealed B-lymphocyte type 2 protein (Bcl-2) BH1- like motifs within the a1 subunit of the NKA to which CET, a drug mimicking Bcl-2 protein BH3-like motifs, might bind thus disrupting NKA function (Lauf et al, 2013). It is unknown by which mechanism CET crosses the plasma membrane to reach its intracellular targets, especially the …

N-Glycosylation, Localization And Trafficking Of Endogenous Nkcc1 In Cos7 Cells, Richa Singh

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The Na+K+2Cl^- co-transporter-1 (NKCC1) effects the electroneutral movement of Na+, K+ and 2Cl^- ions across plasma membranes. NKCC1 is considered a widely distributed, highly N-glycosylated ion transporter involved in the regulation of the intracellular chloride concentration ([Cl^-]i), cell volume and salt secretion. NKCC1 locates in the plasma membrane of all cells studied so far, particularly on the basolateral side of most polarized cells. However, the majority of immunoreactive NKCC1 distributes in intracellular compartments of unknown nature whereas a small proportion of the transporter appears to be located in the plasma membrane. Here, we identified and characterized …

Rwanda: (Limited) Effects Of The First Female Parliamentary Majority In The World, Charlene Anita Raman-Preston

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The case of Rwanda provides a laboratory to explore a unique set of circumstances. This thesis builds upon feminist theory, the literature on post-conflict situations and failed states. It finds that although Rwanda's post-conflict situation provided unexpected and historic opportunities for women to enter politics (a record 64 percent of the members of parliament are female), more women in parliament does not mean the end of patriarchy. Since 1994, Rwanda has experienced significant yet limited progress toward gender equality in employment and education. However, much remains to be done and gender dynamics have not changed substantively. Rather, increasing the numbers …

Computational Analysis Of Vortex Structures In Flapping Flight, Zongxian Liang

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Vortex structures and vortical formation in flapping flight are directly related to the force production. To analyze the connection between vortex structures and aerodynamic performance of flapping flight, we have developed highly efficient algorithms for large-scale flow simulations with moving and deforming bodies. To further understand the underlying mechanisms of force generation caused by the coherent structures of the vortex formation, a new analysis method has been developed to measure the influence of Proper Orthogonal Decomposition (POD) modes on aerodynamic forces.

It is challenging to finish three-dimensional Direct Numerical Simulations (DNS) of insect flight in a limited amount of time. …

Accurate Splicing Of Hdac6 Requires Son, Vishnu Priya Chowdary Battini

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Pre-mRNA splicing requires proper splice site selection mediated by many factors including snRNPs and serine-arginine rich (SR) splicing factors. Son is the largest known SR splicing factor, and it has several putative functional domains including an RS domain, a glycine rich patch (G-patch) and double stranded RNA binding domain (DSRBD). One-third of Son's amino acid sequence consists of novel repetitive sequence motifs of unknown function (Sharma et al., 2010). Son is essential for organization of pre-mRNA processing factors in nuclear speckles and for cell cycle progression (Sharma et al., 2010; Sharma et al., 2011; Ahn et al 2011). Exon array …

Effects Of Red Diamondback Rattlesnake Venom On Keloid Dermal Fibroblasts In Vitro, Mackenzie Shelby Newman

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Keloid scarring is an inflammatory healing response to physical injury such as incision or piercing in the dermis. It is characterized by aberrant extracellular matrix production, the overaccumulation of mature collagen, and excessive fibroblast proliferation and migration beyond the borders of the original wound site. This results in swelling, depigmentation, itchiness, and pain akin to a benign tumor. Although there are myriad treatments for the condition, most are invasive and exhibit a high recurrence rate. Previous studies have shown that rattlesnake venom stimulates apoptosis in the skin via multiple specific mechanisms, largely composed of extracellular matrix and its receptors' interactions. …

Out On The Land: Income, Subsistence Activities, And Food Sharing Networks In Nain, Labrador, Kirk Dombrowski, Emily Channell, Bilal Khan, Joshua Moses, Evan Misshula

Publications and Research

In recent Inuit ethnography, a major concern has been how and to what extent contemporary Inuit participate in and depend on subsistence activities, particularly in the context of increasing wage employment and growing participation in the cash economy. This paper provides an analysis of these activities in the predominately Inuit community of Nain, Labrador. Using social network data and demographic information collected between January and June 2010, we examine the interconnections between subsistence activities—obtaining “country food” through activities such as hunting, fishing, and collecting—with access to the means of obtaining subsistence resources (such as snow mobiles, cabins, and boats), employment …

Arkansas Animal Science Department Report 2012, David L. Kreider

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Probabilistic Cue Combination: Less Is More, Daniel Yurovsky, Ty W. Boyer, Linda B. Smith, Chen Yu

Psychology: Faculty Publications

Learning about the structure of the world requires learning probabilistic relationships: rules in which cues do not predict outcomes with certainty. However, in some cases, the ability to track probabilistic relationships is a handicap, leading adults to perform non-normatively in prediction tasks. For example, in the dilution effect, predictions made from the combination of two cues of different strengths are less accurate than those made from the stronger cue alone. Here we show that dilution is an adult problem; 11-month-old infants combine strong and weak predictors normatively. These results extend and add support for the less is more hypothesis: limited …

The Phylogenetics Of Tachinidae (Insecta: Diptera) With An Emphasis On Subfamily Structure, Daniel J. Davis

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The parasitoid flies of the Tachinidae family are an important and diverse (>10,000 species) lineage of insects. However, tachinids are not well studied partially due to their confusing classification and taxonomy. DNA sequences were obtained from twenty tribal representatives of Tachinidae, along with eight outgroups in order to phylogenetically reconstruct the superfamilial, subfamilial and tribal relationships of Tachinidae. Seven gene regions of six genes (18S, 28S, COI, CAD, Ef1a, and TPI) were sequenced for each taxon (6214 bp total). Both maximum likelihood and Bayesian methods were used to infer phylogenies. The Sarcophagidae and Oestridae were usually reconstructed as monophyletic. …

The Synthesis Of Haplomyrtin Utilizing The Triisopropylsilyl Protecting Group, William S. Barrow

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The synthesis of the arylnaphthalene lignan haplomyrtin using vanillin as a starting material is synthesized via: 1) a bromination of vanillin, 4-hydroxy-5-methoxybenzaldehyde, to produce 6-bromovanillin 2) a hydroxyl protection step of 6-bromovanillin with triisopropylsilylchloride to produce 2-bromo-4-triisopropylsilyoxy-5-methoxybenzaldehyde 3) an aldehyde protection step through a cyclic acetal formation using ethylene glycol to produce 2-(2-bromo-4-triisopropylsilyloxy-5-methoxyphenyl)-1,3-dioxolane 4) a lithium for halogen exchange of the doubly protected 6-bromovanillin leads to neucleophilic coupling with piperonal producing 1,3-benzodioxol-5-yl-[5-triisopropylsilyloxy-2-(1,3-dioxolane-2-yl)-4-methoxyphenyl]methanol and 5) an acid catalyzed intramolecular cycloaddition /Diels Alder adduct with dimethyl acetylenedicarboxylate producing dimethyl 1-(1,3-benzodioxol-5-yl)-4-hydroxy-6-methoxy-7-triisopropylsilyloxynaphthalene-2,3-dicarboxylate.

Can Antibiotics From Recently Discovered Marine Actinobacteria Slow The Tide Of Antibiotic Resistance?, Lorraine Susan Tangeman

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Actinobacteria, one phylum of gram positive bacteria, are found throughout all the environments on earth. Actinobacteria have long been studied for the benefits they provide, both to their environment and to humans, and have a great capacity for adaptation and evolution. They decompose organic matter, replenishing nutrients into the soil, and as such are important members of the food chain. Humans benefit from the exploitation of Actinobacterial metabolites as antimicrobial drugs. These antimicrobials have been effectively utilized for decades in the fight against infectious disease. Despite the success of this drug arsenal we are now in the midst of an …