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Cell and Developmental Biology

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Altered Entrainment To The Day/Night Cycle Attenuates The Daily Rise In Circulating Corticosterone In The Mouse, Patricia J. Sollars, Michael J. Weiser, Andrea E. Kudwa, Jayne R. Bramley, Malcolm D. Ogilvie, Robert L. Spencer, Robert J. Handa, Gary E. Pickard Jan 2014

Altered Entrainment To The Day/Night Cycle Attenuates The Daily Rise In Circulating Corticosterone In The Mouse, Patricia J. Sollars, Michael J. Weiser, Andrea E. Kudwa, Jayne R. Bramley, Malcolm D. Ogilvie, Robert L. Spencer, Robert J. Handa, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

The suprachiasmatic nucleus (SCN) is a circadian oscillator entrained to the day/night cycle via input from the retina. Serotonin (5-HT) afferents to the SCN modulate retinal signals via activation of 5-HT1B receptors, decreasing responsiveness to light. Consequently, 5-HT1B receptor knockout (KO) mice entrain to the day/night cycle with delayed activity onsets. Since circulating corticosterone levels exhibit a robust daily rhythm peaking around activity onset, we asked whether delayed entrainment of activity onsets affects rhythmic corticosterone secretion. Wheel-running activity and plasma corticosterone were monitored in mice housed under several different lighting regimens. Both duration of the light:dark cycle (T …


The Catabolite Control Protein E (Ccpe) Affects Virulence Determinant Production And Pathogenesis Of Staphylococcus Aureus, Torsten Hartmann, Grégory Baronian, Nadine Nippe, Meike Voss, Bettina Schulthess, Christiane Wolz, Janina Eisenbeis, Kerstin Schmidt-Hohagen, Rosmarie Gaupp, Cord Sunderkötter, Christoph Beisswenger, Robert Bals, Greg A. Somerville, Mathias Herrmann, Virginie Molle, Markus Bischoff Jan 2014

The Catabolite Control Protein E (Ccpe) Affects Virulence Determinant Production And Pathogenesis Of Staphylococcus Aureus, Torsten Hartmann, Grégory Baronian, Nadine Nippe, Meike Voss, Bettina Schulthess, Christiane Wolz, Janina Eisenbeis, Kerstin Schmidt-Hohagen, Rosmarie Gaupp, Cord Sunderkötter, Christoph Beisswenger, Robert Bals, Greg A. Somerville, Mathias Herrmann, Virginie Molle, Markus Bischoff

School of Veterinary and Biomedical Sciences: Faculty Publications

Carbon metabolism and virulence determinant production are often linked in pathogenic bacteria, and several regulatory elements have been reported to mediate this linkage in Staphylococcus aureus. Previously, we described a novel protein, catabolite control protein E (CcpE) that functions as a regulator of the tricarboxylic acid cycle. Here we demonstrate that CcpE also regulates virulence determinant biosynthesis and pathogenesis. Specifically, deletion of ccpE in S. aureus strain Newman revealed that CcpE affects transcription of virulence factors such as capA, the first gene in the capsule biosynthetic operon; hla, encoding α-toxin; and psmα, encoding the phenol-soluble modulin cluster α. Electrophoretic mobility …


Sumoylation Differentially Regulates Sp1 To Control Cell Differentiation, Lili Gong, Wei-Ke Ji, Xiao-Hui Hu, Wen-Feng Hu, Xiang-Cheng Tang, Zhao-Xia Huang, Ling Li, Mugen Liu, Shi-Hua Xiang, Erxi Wu, Zachary Woodward, Yi-Zhi Liu, Quan Dong Nguyen, David Wan-Cheng Li Jan 2014

Sumoylation Differentially Regulates Sp1 To Control Cell Differentiation, Lili Gong, Wei-Ke Ji, Xiao-Hui Hu, Wen-Feng Hu, Xiang-Cheng Tang, Zhao-Xia Huang, Ling Li, Mugen Liu, Shi-Hua Xiang, Erxi Wu, Zachary Woodward, Yi-Zhi Liu, Quan Dong Nguyen, David Wan-Cheng Li

School of Veterinary and Biomedical Sciences: Faculty Publications

The mammalian small ubiquitin-like modifiers (SUMOs) are actively involved in regulating differentiation of different cell types. However, the functional differences between SUMO isoforms and their mechanisms of action remain largely unknown. Using the ocular lens as a model system, we demonstrate that different SUMOs display distinct functions in regulating differentiation of epithelial cells into fiber cells. During lens differentiation, SUMO1 and SUMO2/3 displayed different expression, localization, and targets, suggesting differential functions. Indeed, overexpression of SUMO2/3, but not SUMO1, inhibited basic (b) FGF-induced cell differentiation. In contrast, knockdown of SUMO1, but not SUMO2/3, also inhibited bFGF action. Mechanistically, specificity protein 1 …


Protective Humoral Immune Response Induced By An Inactivated Porcine Reproductive And Respiratory Syndrome Virus Expressing The Hypo-Glycosylated Glycoprotein 5, Jung-Ah Lee, Byungjoon Kim, Fernando A. Osorio, Asit K. Pattnaik, Nak-Hyung Lee, Sang-Won Lee, Seung-Yong Park, Chang-Seon Song, In-Soo Choi, Joong-Bok Lee Jan 2014

Protective Humoral Immune Response Induced By An Inactivated Porcine Reproductive And Respiratory Syndrome Virus Expressing The Hypo-Glycosylated Glycoprotein 5, Jung-Ah Lee, Byungjoon Kim, Fernando A. Osorio, Asit K. Pattnaik, Nak-Hyung Lee, Sang-Won Lee, Seung-Yong Park, Chang-Seon Song, In-Soo Choi, Joong-Bok Lee

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome (PRRS) causes significant economic losses to the swine industry worldwide. Although inactivated and live vaccines are commercially available for the control of PRRS, both types of vaccine have not always proven successful in terms of generating a protective immune response, particularly in the case of inactivated vaccines. In this study, we tested whether an inactivated vaccine could induce a humoral immune response to PRRS during a homologous challenge. Amino acid substitutions were introduced into glycoprotein (GP) 5 of the FL12 strain of the PRRS virus (PRRSV) using site-directed mutagenesis with a pFL12 infectious clone. The …


Light Stimulates The Mouse Adrenal Through A Retinohypothalamic Pathway Independent Of An Effect On The Clock In The Suprachiasmatic Nucleus, Silke Kiessling, Patricia J. Sollars, Gary E. Pickard Jan 2014

Light Stimulates The Mouse Adrenal Through A Retinohypothalamic Pathway Independent Of An Effect On The Clock In The Suprachiasmatic Nucleus, Silke Kiessling, Patricia J. Sollars, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

The brain’s master circadian pacemaker resides within the hypothalamic suprachiasmatic nucleus (SCN). SCN clock neurons are entrained to the day/night cycle via the retinohypothalamic tract and the SCN provides temporal information to the central nervous system and to peripheral organs that function as secondary oscillators. The SCN clock-cell network is thought to be the hypothalamic link between the retina and descending autonomic circuits to peripheral organs such as the adrenal gland, thereby entraining those organs to the day/night cycle. However, there are at least three different routes or mechanisms by which retinal signals transmitted to the hypothalamus may be conveyed …


Moraxella Spp. Isolated From Field Outbreaks Of Infectious Bovine Keratoconjunctivitis: A Retrospective Study Of Case Submissions From 2010 To 2013, John Dustin Loy, Bruce W. Brodersen Jan 2014

Moraxella Spp. Isolated From Field Outbreaks Of Infectious Bovine Keratoconjunctivitis: A Retrospective Study Of Case Submissions From 2010 To 2013, John Dustin Loy, Bruce W. Brodersen

School of Veterinary and Biomedical Sciences: Faculty Publications

Infectious bovine keratoconjunctivitis (IBK), also known as pinkeye, is the most costly eye disease of cattle. The principal etiologic agent of IBK is the Gram-negative bacterium Moraxella bovis. However, there have been reports of IBK outbreaks associated with Moraxella bovoculi. A retrospective study of IBK diagnostic cases submitted from July 1, 2010, through October 31, 2013, was conducted. Included in the study were 1,042 Moraxella isolates from 1,538 swabs of lacrimal secretions collected from 282 herds from 30 U.S. states. Moraxella isolates were identified to the species level and were composed of M. bovoculi (701 isolates), M. bovis …


In Situ Detection Of Autoreactive Cd4 T Cells In Brain And Heart Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilamany, Arunakumar Gangaplara, Ting Jia, Christian Elowsky, Qingsheng Li, You Zhou, Jay Reddy Jan 2014

In Situ Detection Of Autoreactive Cd4 T Cells In Brain And Heart Using Major Histocompatibility Complex Class Ii Dextramers, Chandirasegaran Massilamany, Arunakumar Gangaplara, Ting Jia, Christian Elowsky, Qingsheng Li, You Zhou, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

This report demonstrates the use of major histocompatibility complex (MHC) class II dextramers for detection of autoreactive CD4 T cells in situ in myelin proteolipid protein (PLP) 139-151-induced experimental autoimmune encephalomyelitis (EAE) in SJL mice and cardiac myosin heavy chain-α (Myhc) 334-352-induced experimental autoimmune myocarditis (EAM) in A/J mice. Two sets of cocktails of dextramer reagents were used, where dextramers+ cells were analyzed by laser scanning confocal microscope (LSCM): EAE, IAs/PLP 139-151 dextramers (specific)/anti- CD4 and IAs/Theiler’s murine encephalomyelitis virus (TMEV) 70-86 dextramers (control)/anti-CD4; and EAM, IAk/Myhc 334-352 dextramers/ anti-CD4 and IAk/bovine ribonuclease (RNase) 43-56 dextramers (control)/anti-CD4. LSCM analysis of …


Generation Of Calves Persistently Infected With Hobi-Like Pestivirus And Comparison Of Methods For Detection Of These Persistent Infections, F. V. Bauermann, S. M. Falkenberg, B. Vander Ley, N. Decaro, Bruce W. Brodersen, A. Harmon, B. Hessman, E. F. Flores, J. F. Ridpath Jan 2014

Generation Of Calves Persistently Infected With Hobi-Like Pestivirus And Comparison Of Methods For Detection Of These Persistent Infections, F. V. Bauermann, S. M. Falkenberg, B. Vander Ley, N. Decaro, Bruce W. Brodersen, A. Harmon, B. Hessman, E. F. Flores, J. F. Ridpath

School of Veterinary and Biomedical Sciences: Faculty Publications

The identification and elimination of persistently infected (PI) cattle are the most effective measures for controlling bovine pestiviruses, including bovine viral diarrhea virus (BVDV) and the emerging HoBi-like viruses. Here, colostrum-deprived calves persistently infected with HoBi-like pestivirus (HoBi-like PI calves) were generated and sampled (serum, buffy coat, and ear notches) on the day of birth (DOB) and weekly for 5 consecutive weeks. The samples were subjected to diagnostic tests for BVDV—two reverse transcriptase PCR (RT-PCR) assays, two commercial real-time RT quantitative PCR (RT-qPCR), two antigen capture enzyme-linked immunosorbent assays (ACE), and immunohistochemistry (IHC)—and to HoBi-like virus-specific RT-PCR and RT-qPCR assays. …


Generation And Screening Of A Comprehensive Mycobacterium Avium Subsp. Paratuberculosis Transposon Mutant Bank, Govardhan Rathnaiah, Elise A. Lamont, N. Beth Harris, Robert J. Fenton, Denise K. Zinniel, Xiaofei Liu, Josh Sotos, Zhengyu Feng, Ayala Livneh-Kol, Nahum Y. Shpigel, Charles J. Czuprynski, Srinand Sreevatsan, Raul G. Barletta Jan 2014

Generation And Screening Of A Comprehensive Mycobacterium Avium Subsp. Paratuberculosis Transposon Mutant Bank, Govardhan Rathnaiah, Elise A. Lamont, N. Beth Harris, Robert J. Fenton, Denise K. Zinniel, Xiaofei Liu, Josh Sotos, Zhengyu Feng, Ayala Livneh-Kol, Nahum Y. Shpigel, Charles J. Czuprynski, Srinand Sreevatsan, Raul G. Barletta

School of Veterinary and Biomedical Sciences: Faculty Publications

Mycobacterium avium subsp. paratuberculosis (MAP) is the etiologic agent of Johne’s Disease in ruminants. This enteritis has significant economic impact and world wide distribution. Vaccination is one of the most cost effective infectious disease control measures. Unfortunately, current vaccines reduce clinical disease and shedding, but are of limited efficacy and do not provide long-term protective immunity. Several strategies have been followed to mine the MAP genome for virulence determinants that could be applied to vaccine and diagnostic assay developent. In this study, a comprehensive mutant bank of 13,536 MAP K-10 Tn5367 mutants (P>95% )was constructed and screened in …


Noninvasive Assessment Of Cardiac Abnormalities In Experimental Autoimmune Myocarditis By Magnetic Resonance Microscopy Imaging In The Mouse, Chandirasegara Massilamany, Vahid Khalilzad-Sharghi, Arunakumar Gangaplara, David Steffen, Shadi F. Othman, Jay Reddy Jan 2014

Noninvasive Assessment Of Cardiac Abnormalities In Experimental Autoimmune Myocarditis By Magnetic Resonance Microscopy Imaging In The Mouse, Chandirasegara Massilamany, Vahid Khalilzad-Sharghi, Arunakumar Gangaplara, David Steffen, Shadi F. Othman, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Myocarditis is an inflammation of the myocardium, but only ~10% of those affected show clinical manifestations of the disease. To study the immune events of myocardial injuries, various mouse models of myocarditis have been widely used. This study involved experimental autoimmune myocarditis (EAM) induced with cardiac myosin heavy chain (Myhc)-α 334-352 in A/J mice; the affected animals develop lymphocytic myocarditis but with no apparent clinical signs. In this model, the utility of magnetic resonance microscopy (MRM) as a non-invasive modality to determine the cardiac structural and functional changes in animals immunized with Myhc-α 334-352 is shown. EAM and healthy mice …


Intricacies Of Cardiac Damage In Coxsackievirus B3 Infection: Implications For Therapy, Chandirasegara Massilamany, Arunakumar Gangaplara, Jay Reddy Jan 2014

Intricacies Of Cardiac Damage In Coxsackievirus B3 Infection: Implications For Therapy, Chandirasegara Massilamany, Arunakumar Gangaplara, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Heart disease is the leading cause of death in humans, and myocarditis is one predominant cause of heart failure in young adults. Patients affected with myocarditis can develop dilated cardiomyopathy (DCM), a common reason for heart transplantation, which to date is the only viable option for combatting DCM. Myocarditis/DCM patients show antibodies to coxsackievirus B (CVB)3 and cardiac antigens, suggesting a role for CVB-mediated autoimmunity in the disease pathogenesis; however, a direct causal link remains to be determined clinically. Experimentally, myocarditis can be induced in susceptible strains of mice using the human isolates of CVB3, and the disease pathogenesis of …


Direct Staining With Major Histocompatibility Complex Class Ii Dextramers Permits Detection Of Antigen- Specific, Autoreactive Cd4 T Cells In Situ, Chandirasegaran Massilamany, Arunakumar Gangaplara, Ting Jia, Christian Elowsky, Guobin Kang, Jean-Jack Riethoven, Qingsheng Li, You Zhou, Jay Reddy Jan 2014

Direct Staining With Major Histocompatibility Complex Class Ii Dextramers Permits Detection Of Antigen- Specific, Autoreactive Cd4 T Cells In Situ, Chandirasegaran Massilamany, Arunakumar Gangaplara, Ting Jia, Christian Elowsky, Guobin Kang, Jean-Jack Riethoven, Qingsheng Li, You Zhou, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

We report here the utility of major histocompatibility complex (MHC) class II dextramers for in situ detection of self-reactive CD4 T cells in two target organs, the brain and heart. We optimized the conditions for in situ detection of antigen-specific CD4 T cells using brain sections obtained from SJL mice immunized with myelin proteolipid protein (PLP) 139–151; the sections were costained with IAs/PLP 139–151 (specific) or Theiler’s murine encephalomyelitis virus (TMEV) 70–86 (control) dextramers and anti-CD4. Analysis of sections by laser scanning confocal microscope revealed detection of cells positive for PLP 139–151 but not for TMEV 70–86 dextramers …


Influence Of Iron And Aeration On Staphylococcus Aureus Growth, Metabolism, And Transcription, Nagender Ledala, Bo Zhang, Javier Seravalli, Robert Powers, Greg Somerville Jan 2014

Influence Of Iron And Aeration On Staphylococcus Aureus Growth, Metabolism, And Transcription, Nagender Ledala, Bo Zhang, Javier Seravalli, Robert Powers, Greg Somerville

School of Veterinary and Biomedical Sciences: Faculty Publications

Staphylococcus aureus is a prominent nosocomial pathogen and a major cause of biomaterial-associated infections. The success of S. aureus as a pathogen is due in part to its ability to adapt to stressful environments. As an example, the transition from residing in the nares to residing in the blood or deeper tissues is accompanied by changes in the availability of nutrients and elements such as oxygen and iron. As such, nutrients, oxygen, and iron are important determinants of virulence factor synthesis in S. aureus. In addition to influencing virulence factor synthesis, oxygen and iron are critical cofactors in enzymatic and …


Construction Of A Live-Attenuated Hiv-1 Vaccine Through Genetic Code Expansion, Nanxi Wang, Yue Li, Wei Niu, Ming Sun, Ronald Cerny, Qingsheng Li, Jiantao Guo Jan 2014

Construction Of A Live-Attenuated Hiv-1 Vaccine Through Genetic Code Expansion, Nanxi Wang, Yue Li, Wei Niu, Ming Sun, Ronald Cerny, Qingsheng Li, Jiantao Guo

Qingsheng Li Publications

A safe and effective vaccine against human immunodeficiency virus type 1 (HIV-1) is urgently needed to combat the worldwide AIDS pandemic, but still remains elusive. The fact that uncontrolled replication of an attenuated vaccine can lead to regaining of its virulence creates safety concerns precluding many vaccines from clinical application. We introduce a novel approach to control HIV-1 replication, which entails the manipulation of essential HIV-1 protein biosynthesis through unnatural amino acid (UAA*)-mediated suppression of genome-encoded blank codon. We successfully demonstrate that HIV-1 replication can be precisely turned on and off in vitro.

Includes supporting information.


Sjl Mice Infected With Acanthamoeba Castellanii Develop Central Nervous System Autoimmunity Through The Generation Of Cross-Reactive T Cells For Myelin Antigens, Jay Reddy, Chandirasegaran Massilamany, Francine Marciano-Cabral, Bruno Da Rocha-Azevedo, Melissa Jamerson, Arunakumar Gangaplara, David Steffen, Rana Zabad, Zsolt Illes, Raymond Sobel Jan 2014

Sjl Mice Infected With Acanthamoeba Castellanii Develop Central Nervous System Autoimmunity Through The Generation Of Cross-Reactive T Cells For Myelin Antigens, Jay Reddy, Chandirasegaran Massilamany, Francine Marciano-Cabral, Bruno Da Rocha-Azevedo, Melissa Jamerson, Arunakumar Gangaplara, David Steffen, Rana Zabad, Zsolt Illes, Raymond Sobel

School of Veterinary and Biomedical Sciences: Faculty Publications

We recently reported that Acanthamoeba castellanii (ACA), an opportunistic pathogen of the central nervous system (CNS) possesses mimicry epitopes for proteolipid protein (PLP) 139–151 and myelin basic protein 89–101, and that the epitopes induce experimental autoimmune encephalomyelitis (EAE) in SJL mice reminiscent of the diseases induced with their corresponding cognate peptides. We now demonstrate that mice infected with ACA also show the generation of crossreactive T cells, predominantly for PLP 139–151, as evaluated by T cell proliferation and IAs/dextramer staining. We verified that PLP 139–151-sensitized lymphocytes generated in infected mice contained a high proportion of T helper 1 cytokineproducing cells, …


Characterizing Dsrna Production In Virus-Infected Fish Cells, Amal Brek Aloufi Jan 2014

Characterizing Dsrna Production In Virus-Infected Fish Cells, Amal Brek Aloufi

Theses and Dissertations (Comprehensive)

Viral dsRNA is produced by almost all viruses sometime during their replicative cycle. These viral nucleic acids are potent inducers of both innate and adaptive immune responses, and are therefore considered important immuno-modulators. Previous studies have shown that viruses produce dsRNA when replicating in mammalian cells; however, to date no one has demonstrated viral dsRNA production in virus infected fish cells. Therefore, the goal of this study is to investigate dsRNA production by fish viruses in fish cells, verifying production and performing initial characterization of the dsRNA molecules being produced. Three different rainbow trout cell lines were used in this …


Structure-Function Analysis Of Zapc, An Ftsz-Ring Stabilizer, In Escherichia Coli Cytokinesis, Lukasz Tchorzewski Jan 2014

Structure-Function Analysis Of Zapc, An Ftsz-Ring Stabilizer, In Escherichia Coli Cytokinesis, Lukasz Tchorzewski

Dissertations and Theses

In Escherichia coli, cell division is defined by the polymerization and constriction of a cytokinetic ring (Z ring) formed by FtsZ, a tubulin-like GTPase, at midcell. Division also involves the formation of a multi-protein complex at midcell known as the divisome. Several divisome proteins promote the assembly/disassembly processes of FtsZ, thereby exercising spatiotemporal control over division. Among FtsZ regulatory proteins are the FtsZ ringassociated proteins (Zap), which either directly or indirectly stabilize the Z-ring by increasing lateral interactions amongst FtsZ protofilaments in the Z-ring. ZapA-D are recruited during early cytokinesis and have overlapping functions in stabilizing FtsZ at midcell, but …


Development Of Novel Subunit Vaccine Against H5n1 Influenza, Lu Zhang Dec 2013

Development Of Novel Subunit Vaccine Against H5n1 Influenza, Lu Zhang

Graduate Theses and Dissertations

Influenza is a common infectious disease resulting from a frequently mutated RNA virus. Vaccination is currently the most effective method to prevent people from seasonal or pandemic influenza. The production of traditional egg-based influenza vaccine is time-consuming and provides limited effect against new strains. Therefore, it is necessary to develop a rapid method to produce influenza vaccines. We proposed a novel influenza vaccine based on the E.coli expression system. Hemagglutinin (HA) is the major target surface protein of influenza virus for vaccine development. In this study, we sub-cloned the HAs encoding gene into an E. coli expression vector; the signal …


C-Jun N-Terminal Kinases Regulate Adenovirus-Mediated Autophagy And Antigen Presentation, Sarah R. Klein Dec 2013

C-Jun N-Terminal Kinases Regulate Adenovirus-Mediated Autophagy And Antigen Presentation, Sarah R. Klein

Dissertations and Theses (Open Access)

Targeted immunotherapy with recombinant, oncolytic adenoviruses is under investigation for the treatment of cancer. Evidence indicates adenoviruses induce autophagy that is required for oncolysis, but the molecular regulation of autophagy in infected cells remains under investigation. Our data suggested the canonical pathway regulating starvation-induced autophagy was not implemented in adenovirus-induced autophagy; however, adenovirus infection triggered phosphorylation of c-Jun N-terminal kinases (JNK) that was essential for autophagy. Adenoviral replication within the host cell elicited JNK pathway activation leading to B cell lymphoma-2 (Bcl-2) phosphorylation. JNK-dependent Bcl-2 phosphorylation stimulated the dissociation of Bcl-2/beclin 1 heterodimers, enabling beclin 1 to initiate autophagy. Moreover, …


In-Situ Quantification Of The Interfacial Rheological Response Of Bacterial Biofilms To Environmental Stimuli, Patrick Rühs, Lukas Böni, Gerald Fuller, R. Inglis, Peter Fischer Nov 2013

In-Situ Quantification Of The Interfacial Rheological Response Of Bacterial Biofilms To Environmental Stimuli, Patrick Rühs, Lukas Böni, Gerald Fuller, R. Inglis, Peter Fischer

Biology Department Faculty Works

Understanding the numerous factors that can affect biofilm formation and stability remain poorly understood. One of the major limitations is the accurate measurement of biofilm stability and cohesiveness in real-time when exposed to changing environmental conditions. Here we present a novel method to measure biofilm strength: interfacial rheology. By culturing a range of bacterial biofilms on an air-liquid interface we were able to measure their viscoelastic growth profile during and after biofilm formation and subsequently alter growth conditions by adding surfactants or changing the nutrient composition of the growth medium. We found that different bacterial species had unique viscoelastic growth …


Small Molecule Antagonists Of Melanopsin-Mediated Phototransduction, Kenneth A. Jones, Megumi Hatori, Ludovic S. Mure, Jayne R. Bramley, Roman Artymyshyn, Sang-Phyo Hong, Mohammad Marzabadi, Huailing Zhong, Jeffrey Sprouse, Quansheng Zhu, Andrew T. E. Hartwick, Patricia J. Sollars, Gary E. Pickard, Satchidananda Panda Oct 2013

Small Molecule Antagonists Of Melanopsin-Mediated Phototransduction, Kenneth A. Jones, Megumi Hatori, Ludovic S. Mure, Jayne R. Bramley, Roman Artymyshyn, Sang-Phyo Hong, Mohammad Marzabadi, Huailing Zhong, Jeffrey Sprouse, Quansheng Zhu, Andrew T. E. Hartwick, Patricia J. Sollars, Gary E. Pickard, Satchidananda Panda

School of Veterinary and Biomedical Sciences: Faculty Publications

Melanopsin, expressed in a subset of retinal ganglion cells, mediates behavioral adaptation to ambient light and other non-image forming photic responses. This has raised the possibility that pharmacological manipulation of melanopsin can modulate several CNS responses including photophobia, sleep, circadian rhythms and neuroendocrine function. Here we describe the identification of a potent synthetic melanopsin antagonist with in vivo activity. Novel sulfonamide compounds inhibiting melanopsin (opsinamides) compete with retinal binding to melanopsin and inhibit its function without affecting rod/cone mediated responses. In vivo administration of opsinamides to mice specifically and reversibly modified melanopsin-dependent light responses including the pupillary light reflex and …


Pseudomonas Aeruginosa Exotoxin Y-Mediated Tau Hyperphosphorylation Impairs Microtubule Assembly In Pulmonary Microvascular Endothelial Cells, Ron Balczon, Nutan Prasain, Cristhiaan Ochoa, Jason Prater, Bing Zhu, Mikhail Alexeyev, Sarah Sayner, Dara W. Frank, Troy Stevens Sep 2013

Pseudomonas Aeruginosa Exotoxin Y-Mediated Tau Hyperphosphorylation Impairs Microtubule Assembly In Pulmonary Microvascular Endothelial Cells, Ron Balczon, Nutan Prasain, Cristhiaan Ochoa, Jason Prater, Bing Zhu, Mikhail Alexeyev, Sarah Sayner, Dara W. Frank, Troy Stevens

University Faculty and Staff Publications

Pseudomonas aeruginosa uses a type III secretion system to introduce the adenylyl and guanylyl cyclase exotoxin Y (ExoY) into the cytoplasm of endothelial cells. ExoY induces Tau hyperphosphorylation and insolubility, microtubule breakdown, barrier disruption and edema, although the mechanism(s) responsible for microtubule breakdown remain poorly understood. Here we investigated both microtubule behavior and centrosome activity to test the hypothesis that ExoY disrupts microtubule dynamics. Fluorescence microscopy determined that infected pulmonary microvascular endothelial cells contained fewer microtubules than control cells, and further studies demonstrated that the microtubule-associated protein Tau was hyperphosphorylated following infection and dissociated from microtubules. Disassembly/reassembly studies determined that …


Resistance Of Human Cytomegalovirus To Cyclopropavir Maps To A Base Pair Deletion In The Open Reading Frame Of Ul97, Brian G. Gentry, Laura E. Vollmer, Ellie D. Hall, Katherine Z. Borysko, Jiri Zemlicka, Jeremy P. Kamil, John C. Drach Sep 2013

Resistance Of Human Cytomegalovirus To Cyclopropavir Maps To A Base Pair Deletion In The Open Reading Frame Of Ul97, Brian G. Gentry, Laura E. Vollmer, Ellie D. Hall, Katherine Z. Borysko, Jiri Zemlicka, Jeremy P. Kamil, John C. Drach

Oncology Faculty Publications

Human cytomegalovirus (HCMV) is a widespread pathogen in the human population, affecting many immunologically immature and immunocompromised patients, and can result in severe complications, such as interstitial pneumonia and mental retardation. Current chemotherapies for the treatment of HCMV infections include ganciclovir (GCV), foscarnet, and cidofovir. However, the high incidences of adverse effects (neutropenia and nephrotoxicity) limit the use of these drugs. Cyclopropavir (CPV), a guanosine nucleoside analog, is 10-fold more active against HCMV than GCV (50% effective concentrations [EC50s] = 0.46 and 4.1 μM, respectively). We hypothesize that the mechanism of action of CPV is similar to that …


Barrier To Autointegration Factor (Baf) Inhibits Vaccinia Virus Intermediate Transcription In The Absence Of The Viral B1 Kinase, Nouhou Ibrahim, April Wicklund, Augusta Jamin, Matthew S. Wiebe Sep 2013

Barrier To Autointegration Factor (Baf) Inhibits Vaccinia Virus Intermediate Transcription In The Absence Of The Viral B1 Kinase, Nouhou Ibrahim, April Wicklund, Augusta Jamin, Matthew S. Wiebe

Nebraska Center for Virology: Faculty Publications

Barrier to autointegration factor (BAF/BANF1) is a cellular DNA-binding protein found in the nucleus and cytoplasm. Cytoplasmic BAF binds to foreign DNA and can act as a defense against vaccinia DNA replication. To evade BAF, vaccinia expresses the B1 kinase, which phosphorylates BAF and blocks its ability to bind DNA. Interestingly, B1 is also needed for viral intermediate gene expression via an unknown mechanism. Therefore, we evaluated the impact of B1-BAF signaling on vaccinia transcription. Strikingly, the decrease in vaccinia transcription caused by loss of B1 can be rescued by depletion of BAF. The repressive action of BAF is greatest …


Early Innate Immunity Determines Outcome Of Mycobacterium Tuberculosis Pulmonary Infection In Rabbits, Selvakumar Subbian, Nirmalya Bandyopadhyay, Liana Tsenova, Paul O'Brien, Viraj Khetani, Nicole L. Kushner, Blas Peixoto, Patricia Soteropoulos, Joel S. Bader, Petros C. Karakousis, Dorothy Fallows, Gilla Kaplan Aug 2013

Early Innate Immunity Determines Outcome Of Mycobacterium Tuberculosis Pulmonary Infection In Rabbits, Selvakumar Subbian, Nirmalya Bandyopadhyay, Liana Tsenova, Paul O'Brien, Viraj Khetani, Nicole L. Kushner, Blas Peixoto, Patricia Soteropoulos, Joel S. Bader, Petros C. Karakousis, Dorothy Fallows, Gilla Kaplan

Publications and Research

Background: Pulmonary infection of humans by Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), results in active disease in 5-10% of individuals, while asymptomatic latent Mtb infection (LTBI) is established in the remainder. The host immune responses that determine this differential outcome following Mtb infection are not fully understood. Using a rabbit model of pulmonary TB, we have shown that infection with the Mtb clinical isolate HN878 (a hyper-virulent W-Beijing lineage strain) leads to progressive cavitary disease similar to what is seen in humans with active TB. In contrast, infection with Mtb CDC1551 (a hyper-immunogenic clinical isolate) is efficiently …


Osmotic Stress, Not Aldose Reductase Activity, Directly Induces Growth Factors And Mapk Signaling Changes During Sugar Cataract Formation, Peng Zhang, Kuiyi Xing, James Randazzo, Karen Blessing, Marjorie F. Lou, Peter Kador Aug 2013

Osmotic Stress, Not Aldose Reductase Activity, Directly Induces Growth Factors And Mapk Signaling Changes During Sugar Cataract Formation, Peng Zhang, Kuiyi Xing, James Randazzo, Karen Blessing, Marjorie F. Lou, Peter Kador

School of Veterinary and Biomedical Sciences: Faculty Publications

In sugar cataract formation in rats, aldose reductase (AR) actitvity is not only linked to lenticular sorbitol (diabetic) or galactitol (galactosemic) formation but also to signal transduction changes, cytotoxic signals and activation of apoptosis. Using both in vitro and in vivo techniques, the interrelationship between AR activity, polyol (sorbitol and galactitol) formation, osmotic stress, growth factor induction, and cell signaling changes have been investigated. For in vitro studies, lenses from Sprague Dawley rats were cultured for up to 48 hrs in TC-199-bicarbonate media containing either 30 mM fructose (control), or 30 mM glucose or galctose with/without the aldose reductase inhibitors …


T-Cell Treatments For Solid And Hematological Tumors, Drew C. Deniger Aug 2013

T-Cell Treatments For Solid And Hematological Tumors, Drew C. Deniger

Dissertations and Theses (Open Access)

Cell-based therapies have demonstrated potency and efficacy as cancer treatment modalities. T cells can be dichotomized by their T cell receptor (TCR) complexes where alpha/beta T cells (95% of T cells) and gamma/delta T cells (+T cells proliferated to clinically significant numbers and ROR1+ tumor cells were effectively targeted and killed by both ROR1-specific CAR+ T cell populations, although ROR1RCD137 were superior to ROR1RCD28 in clearance of leukemia xenografts in vivo. The second specific aim focused on generating bi-specific CD19-specific CAR+ gamma/delta T cells with polyclonal TCRgamma/delta repertoire on CD19+ artificial antigen presenting cells (aAPC). …


Heterogeneous Nuclear Ribonucleoprotein K Supports Vesicular Stomatitis Virus Replication By Regulating Cell Survival And Cellular Gene Expression, Phat X. Dinh, Anshuman Das, Rodrigo Franco, Asit K. Pattnaik Jul 2013

Heterogeneous Nuclear Ribonucleoprotein K Supports Vesicular Stomatitis Virus Replication By Regulating Cell Survival And Cellular Gene Expression, Phat X. Dinh, Anshuman Das, Rodrigo Franco, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

The heterogeneous nuclear ribonucleoprotein K (hnRNP K) is a member of the family of hnRNPs and was recently shown in a genome-wide small interfering RNA (siRNA) screen to support vesicular stomatitis virus (VSV) growth. To decipher the role of hnRNP K in VSV infection, we conducted studies which suggest that the protein is required for VSV spreading. Virus binding to cells, entry, and nucleocapsid uncoating steps were not adversely affected in the absence of hnRNP K, whereas viral genome transcription and replication were reduced slightly. These results indicate that hnRNP K is likely involved in virus assembly and/or release from …


Use Of Image Cytometry For Quantification Of Pathogenic Fungi In Association With Host Cells, Charlotte A. Berkes, Leo Li-Ying Chan, Alisha Wilkinson, Benjamin Paradis Jun 2013

Use Of Image Cytometry For Quantification Of Pathogenic Fungi In Association With Host Cells, Charlotte A. Berkes, Leo Li-Ying Chan, Alisha Wilkinson, Benjamin Paradis

Biology Faculty Publications

Studies of the cellular pathogenesis mechanisms of pathogenic yeasts such as Candida albicans, Histoplasma capsulatum, and Cryptococcus neoformans commonly employ infection of mammalian hosts or host cells (i.e. macrophages) followed by yeast quantification using colony forming unit analysis or flow cytometry. While colony forming unit enumeration has been the most commonly used method in the field, this technique has disadvantages and limitations, including slow growth of some fungal species on solid media and low and/or variable plating efficiencies, which is of particular concern when comparing growth of wild-type and mutant strains. Flow cytometry can provide rapid quantitative information regarding yeast …


Analysis Of The Chondroitinase Operon Of Flavobacterium Columnare, Erin L. Sorlien May 2013

Analysis Of The Chondroitinase Operon Of Flavobacterium Columnare, Erin L. Sorlien

Senior Honors Projects

Analysis of the chondroitinase operon of Flavobacterium columnare

Erin Sorlien

Major

Cell and Molecular Biology, Chemistry

Advisor

Dr. David R. Nelson

Date

May 2, 2013

Keywords

Flavobacterium columnare, columnaris disease, chondroitin AC lyase, complementation, csl operon

Abstract
Flavobacterium columnare, an opportunistic bacterial pathogen of fish, is the causative agent of columnaris disease (CD). The bacterium is a Gram-negative rod that exhibits gliding motility and avidly forms biofilms. CD affects both wild and cultured freshwater fish, and continues to cause large economic losses to the fish farming industry. According to an investigation conducted by the National Animal Health Monitoring System, CD …