Medicine and Health Sciences Commons^™

Enhancement Of Reactive Oxygen Species Production And Chlamydial Infection By The Mitochondrial Nod-Like Family Member Nlrx1, Ali A. Abdul-Sater, Najwene Saïd-Sadier, Verissa M. Lam, Bhavni Singh, Matthew A. Pettengill, Fraser Soares, Ivan Tattoli, Simone Lipinski, Stephen E. Girardin, Philip Rosenstiel, David M. Ojcius

All Dugoni School of Dentistry Faculty Articles

Chlamydia trachomatis infections cause severe and irreversible damage that can lead to infertility and blindness in both males and females. Following infection of epithelial cells, Chlamydia induces production of reactive oxygen species (ROS). Unconventionally, Chlamydiae use ROS to their advantage by activating caspase-1, which contributes to chlamydial growth. NLRX1, a member of the Nod-like receptor family that translocates to the mitochondria, can augment ROS production from the mitochondria following Shigella flexneri infections. However, in general, ROS can also be produced by membrane-bound NADPH oxidases. Given the importance of ROS-induced caspase-1 activation in growth of the chlamydial vacuole, we investigated the …

H-Ns Binding And Repression Of The Ctx Promoter In Vibrio Cholerae, Emily A. Stonehouse, Robin R. Hulbert, Melinda B. Nye, Karen Skorupski, Ronald K. Taylor

Dartmouth Scholarship

Expression of the ctx and tcp genes, which encode cholera toxin and the toxin coregulated pilus, the Vibrio cholerae O1 virulence determinants having the largest contribution to cholera disease, is repressed by the nucleoid-associated protein H-NS and activated by the AraC-like transcriptional regulator ToxT. To elucidate the molecular mechanism by which H-NS controls transcription of the ctxAB operon, H-NS repression and binding were characterized by using a promoter truncation series, gel mobility shift assays, and DNase I footprinting. Promoter regions found to be important for H-NS repression correlated with in vitro binding. Four main H-NS binding regions are present at …

Study Of Two Human Myotubularin Homologs (Atmtm1 And Atmtm2) In Arabidopsis, Yang Zhao

School of Biological Sciences: Dissertations, Theses, and Student Research

Phosphatidylinositol 5 phosphate is appearing to play an important role in signal transduction as lipid second messenger. The synthesis of this lipid signal is mainly conducted by a group of phosphatase called myotubularins (MTM) which can dephosphorylate on the 3’s position of Phosphatidylinositol (3, 5) bi-phosphate. Mutations in active myotubularins lead to severe diseases in human. However, this essential family has been scarcely studied in plants. Recently, two myotubularins (AtMTM1 and AtMTM2) have been identified as the homologs of human MTM Related protein 2 (MTMR2) in Arabidopsis. While some evidence has been provided to suggest the function of AtMTM1, …

Campylobacter Ureolyticus: An Emerging Gastrointestinal Pathogen?, Susan Bullman, Daniel Corcoran, James O'Leary, Brigid Lucey, Deirdre Byrne, Roy D. Sleator

Department of Biological Sciences Publications

A total of 7194 faecal samples collected over a 1-year period from patients presenting with diarrhoea were screened for Campylobacter spp. using EntericBios, a multiplex-PCR system. Of 349 Campylobacter-positive samples, 23.8% were shown to be Campylobacter ureolyticus, using a combination of 16S rRNA gene analysis and highly specific primers targeting the HSP60 gene of this organism. This is, to the best of our knowledge, the first report of C. ureolyticus in the faeces of patients presenting with gastroenteritis and may suggest a role for this organism as an emerging enteric pathogen.

Network Science: Using Information Technology To Enable Collaboration, Arden L. Bement Jr.

PPRI Digital Library

No abstract provided.

Mycotoxins In Grains – Causes, Prevention And Control, Hester F. Vismer

INTSORMIL Presentations

Discusses mycotoxins, their effect on grain, mitigation considerations, and resulting human toxicology.

An Assessment Of The Use Of Chimpanzees In Hepatitis C Research Past, Present And Future: 2. Alternative Replacement Methods, Jarrod Bailey

Experimentation Collection

The use of chimpanzees in hepatitis C virus (HCV) research was examined in the report associated with this paper (1: Validity of the Chimpanzee Model), in which it was concluded that claims of past necessity of chimpanzee use were exaggerated, and that claims of current and future indispensability were unjustifiable. Furthermore, given the serious scientific and ethical issues surrounding chimpanzee experimentation, it was proposed that it must now be considered redundant — particularly in light of the demonstrable contribution of alternative methods to past and current scientific progress, and the future promise that these methods hold. This paper builds on …

An Assessment Of The Use Of Chimpanzees In Hepatitis C Research Past, Present And Future: 1. Validity Of The Chimpanzee Model, Jarrod Bailey

Experimentation Collection

The USA is the only significant user of chimpanzees in biomedical research in the world, since many countries have banned or limited the practice due to substantial ethical, economic and scientific concerns. Advocates of chimpanzee use cite hepatitis C research as a major reason for its necessity and continuation, in spite of supporting evidence that is scant and often anecdotal. This paper examines the scientific and ethical issues surrounding chimpanzee hepatitis C research, and concludes that claims of the necessity of chimpanzees in historical and future hepatitis C research are exaggerated and unjustifiable, respectively. The chimpanzee model has several major …

Lateral Blood Flow Velocity Estimation Based On Ultrasound Speckle Size Change With Scan Velocity, Tiantian Xu, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Conventional (Doppler-based) blood flow velocity measurement methods using ultrasound are capable of resolving the axial component (i.e., that aligned with the ultrasound propagation direction) of the blood flow velocity vector. However, these methods are incapable of detecting blood flow in the direction normal to the ultrasound beam. In addition, these methods require repeated pulse-echo interrogation at the same spatial location. A new method has been introduced which estimates the lateral component of blood flow within a single image frame using the observation that the speckle pattern corresponding to blood reflectors (typically red blood cells) stretches (i.e., is smeared) if the …

Mechanism Of N-Methylation By The Trna M1g37 Methyltransferase Trm5., Thomas Christian, Georges Lahoud, Cuiping Liu, Katherine Hoffmann, John J Perona, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

Trm5 is a eukaryal and archaeal tRNA methyltransferase that catalyzes methyl transfer from S-adenosylmethionine (AdoMet) to the N(1) position of G37 directly 3' to the anticodon. While the biological role of m(1)G37 in enhancing translational fidelity is well established, the catalytic mechanism of Trm5 has remained obscure. To address the mechanism of Trm5 and more broadly the mechanism of N-methylation to nucleobases, we examined the pH-activity profile of an archaeal Trm5 enzyme, and performed structure-guided mutational analysis. The data reveal a marked dependence of enzyme-catalyzed methyl transfer on hydrogen ion equilibria: the single-turnover rate constant for methylation increases by one …

Caffeine Supplementation And Moderate Intensity Exercise Modulates The Cytotoxic Lymphocyte Subset (Cd+8) In Naive And Tolerant Individuals, Elizabeth Ann Fedor

Masters Theses & Specialist Projects

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, …

Arkansas Animal Science Department Report 2010, David L. Kreider

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Staphylococcus Aureus Virulence Factors Synthesis Is Controlled By Central Metabolism, Yefei Zhu

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Staphylococcus aureus is a versatile pathogen that can survive in diverse host environments. This versatility depends on its ability to sense nutrients and respond by modulating gene expression, including the synthesis of virulence determinants. In addition to its ability to synthesize virulence factors, the capacity of S. aureus to form biofilms is an important mediator of virulence in certain infections. Biofilms are a complex aggregation of bacteria commonly encapsulated by an adhesive exopolysaccharide matrix (polysaccharide intercellular adhesin; PIA). To study S. aureus biofilm formation, we assessed the metabolic requirements of S. aureus growing in a biofilm and found the bacteria …

Effects Of A Simulated Tennis Match On Lymphocyte Subset Measurements, Holly Kell

Masters Theses & Specialist Projects

Research has shown that maximal exercise has a significant effect on cells of the immune system. Specifically, lymphocyte count increases during exercise and decreases to a value lower than baseline following an acute exhaustive bout of exercise. The overall lymphocyte response is well characterized, however, the ability of exercise to affect lymphocyte subfractions is unknown to our knowledge. The purpose of this study was to assess and evaluate the affects of a simulated tennis match across two sessions on lymphocyte subsets.

Initial measurements such as age, height, weight, skinfold analysis, and heart rate were recorded for each player, as well …

Development And Validation Of A Rapid Multi-Class Method For The Confirmation Of Fourteen Prohibited Medicinal Additives In Pig And Poultry Compound Feed By Liquid Chromatography Tandem Mass Spectrometry, Mark Cronly, Patrice Behan, Barry Foley, Liam Regan, Marella Gallagher, Sean Earley, Paula Shearan, Edward Malone

Articles

A confirmatory method has been developed to allow for the analysis of fourteen prohibited medicinal additives in pig and poultry compound feed. These compounds are prohibited for use as feed additives although some are still authorised for use in medicated feed. Feed samples are extracted by acetonitrile with addition of sodium sulphate. The extracts undergo a hexane wash to aid with sample purification. The extracts are then evaporated to dryness and reconstituted in initial mobile phase. The samples undergo an ultracentrifugation step prior to injection onto the LC-MS/MS system and are analysed in a run time of 26 minutes. The …

Minimum Description Length And Empirical Bayes Methods Of Identifying Snps Associated With Disease, Ye Yang, David R. Bickel

COBRA Preprint Series

The goal of determining which of hundreds of thousands of SNPs are associated with disease poses one of the most challenging multiple testing problems. Using the empirical Bayes approach, the local false discovery rate (LFDR) estimated using popular semiparametric models has enjoyed success in simultaneous inference. However, the estimated LFDR can be biased because the semiparametric approach tends to overestimate the proportion of the non-associated single nucleotide polymorphisms (SNPs). One of the negative consequences is that, like conventional p-values, such LFDR estimates cannot quantify the amount of information in the data that favors the null hypothesis of no disease-association.

We …

An Archaeal Trna-Synthetase Complex That Enhances Aminoacylation Under Extreme Conditions, Vlatka Godinic-Mikulcic, Jelena Jaric, Corinne D. Hausmann, Michael Ibba, Ivana Weygand-Durasevic

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Aminoacyl-tRNA synthetases (aaRSs) play an integral role in protein synthesis, functioning to attach the correct amino acid with its cognate tRNA molecule. AaRSs are known to associate into higher-order multi-aminoacyl-tRNA synthetase complexes (MSC) involved in archaeal and eukaryotic translation, although the precise biological role remains largely unknown. To gain further insights into archaeal MSCs, possible protein-protein interactions with the atypical Methanothermobacter thermautotrophicus seryl-tRNA synthetase (MtSerRS) were investigated. Yeast two-hybrid analysis revealed arginyl-tRNA synthetase (MtArgRS) as an interacting partner of MtSerRS. Surface plasmon resonance confirmed stable complex formation, with a dissociation constant (KD) of 250 nm. Formation of the MtSerRS·MtArgRS complex …

Role Of Alpha 7 Nicotinic Acetylcholine Receptor In Calcium Signaling Induced By Prion Protein Interaction With Stress-Inducible Protein 1, Flavio H. Beraldo, Camila P. Arantes, Tiago G. Santos, Nicolle G. T. Queiroz, Kirk Young, Jane R. Rylett, Regina P. Markus, Marco A. M. Prado, Vilma R. Martins

Anatomy and Cell Biology Publications

The prion protein (PrP(C)) is a conserved glycosylphosphatidyl-inositol-anchored cell surface protein expressed by neurons and other cells. Stress-inducible protein 1 (STI1) binds PrP(C) extracellularly, and this activated signaling complex promotes neuronal differentiation and neuroprotection via the extracellular signal-regulated kinase 1 and 2 (ERK1/2) and cAMP-dependent protein kinase 1 (PKA) pathways. However, the mechanism by which the PrPC-STI1 interaction transduces extracellular signals to the intracellular environment is unknown. We found that in hippocampal neurons, STI1-PrP(C) engagement induces an increase in intracellular Ca(2+) levels. This effect was not detected in PrP(C)-null neurons or wild-type neurons treated with an STI1 mutant unable to …

A Comparison Of Job Responsibility And Activities Between Registered Dietitians With A Bachelor's Degree And Those With A Master's Degree, Stephanie M. Pillow

FIU Electronic Theses and Dissertations

Minimal educational requirements for Registered Dietitians (RDs) include a bachelor’s degree and practice program. Recently, a master’s degree was recommended. Studies have not established whether education affects employment. A secondary analysis of 2005 Dietetics Practice Audit data determined whether job responsibility, individuals supervised, and activities differed between 1,626 bachelor’s RDs (B-RDs) and 767 master’s (M-RDs) RDs, registered ≤5 years. Chi-square and ANOVA analyzed differences between B-RDs and M-RDs, at entry-level (0-3 years experience) and beyond-entry-level (3+-5 years experience). Beyond-entry-level B-RDs (31.8%) and entry-level M-RDs (31.9%) reported “supervisor/executive” responsibility more than entry-level B-RDs (26.5%; p=0.01). A higher percentage of M-RDs supervised …

Qualitative Study To Determine Quality Of Life Factors Based On Reported Efnep Sucess Stories, Megan L. Hlavacek

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

The purpose of this study was to develop an understanding of how adult participants describe quality of life during or after participation in the Expanded Food and Nutrition Education Program (EFNEP) at sites across the United States. The study analyzed success stories submitted by EFNEP staff and participants from sites in nine states from the years 2004 to 2010. A total of 1,057 success stories were analyzed.

The success stories were descriptions of the participants’ experiences with EFNEP. The stories were analyzed by highlighting words, phrases, and/or sentences, and creating a short one to three word codes that would best …

Predicting Intentions To Continue Exclusive Breastfeeding For 6 Months: A Comparison Among Racial/Ethnic Groups, Yeon Bai, Shahla M. Wunderlich, Alyce D. Fly

Department of Nutrition and Food Studies Scholarship and Creative Works

The purpose of this study was to explore how mothers of different races/ethnicities make decisions to continue exclusive breastfeeding (EBF) for 6 months under the Theory of Planned Behavior. Participants were recruited from hospitals and WIC clinics in Central Indiana and Southern New Jersey from 2008 to 2009. Mothers (N = 236: 93 non-Hispanic African American, 72 non-Hispanic white, 71 Hispanic/Latina) completed a self-administered questionnaire that measured theoretical constructs and beliefs related to their intention to practice EBF for 6 months. Intentions to continue EBF for 6 months were similar (P = 0.15) across racial/ethnic groups. Significant proportions of the …

Endogenous Sirnas And Noncoding Rna-Derived Small Rnas Are Expressed In Adult Mouse Hippocampus And Are Up-Regulated In Olfactory Discrimination Training., Neil Smalheiser, G Lugli, Jyothi Thimmapuram, E.H. Cook, J Larson

Cyber Center Publications

We previously proposed that endogenous siRNAs may regulate synaptic plasticity and long-term gene expression in the mammalian brain. Here, a hippocampal-dependent task was employed in which adult mice were trained to execute a nose-poke in a port containing one of two simultaneously present odors in order to obtain a reward. Mice demonstrating olfactory discrimination training were compared to pseudo-training and nose-poke control groups; size-selected hippocampal RNA was subjected to Illumina deep sequencing. Sequences that aligned uniquely and exactly to the genome without uncertain nucleotide assignments, within exons or introns of MGI annotated genes, were examined further. The data confirm that …

Egf Receptor Kinase Activity Is Required For Gap Junction Closure And For Part Of The Decrease In Ovarian Follicle Cgmp In Response To Luteinizing Hormone, Rachael P. Norris, Marina Freudzon, Viacheslav O. Nikolaev, Laurinda A. Jaffe

UCHC Articles - Research

The meiotic cell cycle in mouse oocytes is arrested in prophase, and then restarted when luteinizing hormone (LH) acts on the surrounding granulosa cells. The granulosa cells keep meiosis arrested by providing a source of cGMP that diffuses into the oocyte through gap junctions, and LH restarts the cell cycle by closing the junctions and by decreasing granulosa cell cGMP, thus lowering oocyte cGMP. Epidermal growth factor receptor (EGFR) activation is an essential step in triggering LH-induced meiotic resumption, but its relationship to the cGMP decrease in the follicle is incompletely understood, and its possible function in causing gap junction …

Mhc Class I And Tcr Avidity Control The Cd8 T Cell Response To Il-15/Il-15rα Complex, Thomas A. Stoklasek, Sara L. Colpitts, Henry M. Smilowitz, Leo Lefrançois

UCHC Articles - Research

IL-15 operates via a unique mechanism termed transpresentation. In this system, IL-15 produced by one cell type is bound to IL-15Rα expressed by the same cell and is presented to apposing cells expressing the IL-15Rβ/γC complex. We have shown that administering soluble IL-15Rα complexed with IL-15 can greatly enhance IL-15 activity. We now show that the naive CD8 T cell response to exogenous IL-15/IL-15Rα complex is MHC class I dependent. In the absence of β2 microglobulin, naive CD8 T cells scarcely proliferated in response to IL-15/IL-15Rα complex, whereas memory cells proliferated, although to a lesser extent, compared with levels in …

The Decade Of The Dendritic Nmda Spike, Srdjan D. Antic, Wen-Liang Zho, Anna R. Moore, Shaina M. Shor, Katerina D. Ikonomu

UCHC Articles - Research

In the field of cortical cellular physiology, much effort has been invested in understanding thick apical drites of pyramidal neurons and the regenerative sodium and calcium spikes that take place in the apical trunk. Here we focus on thin dendrites of pyramidal cells (basal, oblique, and tuft dendrites), and we discuss one relatively novel form of an electrical signal (“NMDA spike”) that is specific for these branches. Basal, oblique, and apical tuft dendrites receive a high density of glutamatergic synaptic contacts. Synchronous activation of 10–50 neighboring glutamatergic synapses triggers a local dendritic regenerative potential, NMDA spike/plateau, which is characterized by …

Optimising Maternal Sources Of Breastfeeding During The First Six Weeks Of Postpartum, Roslyn Tarrant, Katherine Younger, Margaret Sheridan-Pereira, John M. Kearney

Conference Papers

No abstract provided.

3,4-Methylenedioxymethamphetamine Alters Left Ventricular Function And Activates Nuclear Factor-Kappa B (Nf-Kappab) In A Time And Dose Dependent Manner, David A. Tiangco, Sapna Halcomb, Frank A. Lattanzio Jr, Barbara Y. Hargrave

Bioelectrics Publications

3,4-Methylenedioxymethamphetamine (MDMA) is an illicit psychoactive drug with cardiovascular effects that have not been fully described. In the current study, we observed the effects of acute MDMA on rabbit left ventricular function. We also observed the effects of MDMA on nuclear factor-kappa B (NF-kappa B) activity in cultured rat ventricular myocytes (H9c2). In the rabbit, MDMA (2 mg/kg) alone caused a significant increase in heart rate and a significant decrease in the duration of the cardiac cycle. Inhibition of nitric oxide synthase (NOS) by pretreatment with L-NAME (10 mg/kg) alone caused significant dysfunction in heart rate, systolic pressure, diastolic pressure, …

Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, Jon C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig

Collected Faculty and Staff Scholarship

Mutations in the Plasmodium falciparum chloroquine (CQ) resistance transporter (PfCRT), are major determinants of verapamil (VP)-reversible CQ resistance (CQR). In the presence of mutant PfCRT, additional genes contribute to the wide range of CQ susceptibilities observed. It is not known if these genes influence mechanisms of chemosensitization by CQR reversal agents. Using quantitative trait locus (QTL) mapping of progeny clones from the HB3 × Dd2 cross, we show that the P. falciparum multidrug resistance gene 1 (pfmdr1) interacts with the Southeast Asiaderived mutant pfcrt haplotype to modulate CQR levels. A novel chromosome 7 locus is predicted to contribute with the …

Neonatal Mortality And Prevalence Of Practices For Newborn Care In A Squatter Settlement Of Karachi, Pakistan: A Cross-Sectional Study., Afsheen Ayaz, Sarah Saleem

Department of Pathology and Laboratory Medicine

Background: During the past two decades there has been a sustained decline in child and infant mortality, however neonatal mortality has remained relatively unchanged. Almost all neonatal deaths (99%) occur in developing countries, where the majority are delivered at homes. Evidence suggests that these deaths could be prevented by simple, inexpensive practices and interventions during the pregnancy, delivery and postnatal period. In Pakistan over the last decade extensive efforts have been made by the international donors and government to implement these practices. However, limited attempts have been made to explore if these efforts have made a difference at the grass …

Chronic Gastritis And Helicobacter Pylori: A Histopathological Study Of Gastric Mucosal Biopsies, Mohammad Yawar Yakoob, Akbar Shah Hussainy

Department of Pathology and Laboratory Medicine

The aim of this study was to observe the histological features of chronic gastritis and associated effects due to Helicobacter pylori infection in 176 randomly selected antral biopsy specimens of chronic gastritis cases. The specimens were reviewed for the presence or absence of H.pylori. The activity (neutrophilic infiltration) of gastritis and the presence or absence of mucosa-associated lymphoid tissue (MALT) were also noted. Chi-square test (Pearson value) was used to analyze categorical variables. H.pylori was detected in 110 (62.5%) cases of chronic gastritis. There was a significant association between H.pylori infection and activity of chronic gastritis (p=0.002). Lymphoid aggregates were …