Veterinary Pathology and Pathobiology Commons^™

Low Levels Of Hydrogen Peroxide Stimulate Corneal Epithelial Cell Adhesion, Migration, And Wound Healing, Qing Pan, Wen-Ya Qiu, Ya-Nan Huo, Yu-Feng Yao, Marjorie F. Lou

School of Veterinary and Biomedical Sciences: Faculty Publications

PURPOSE. Intracellular reactive oxygen species have been reported to associate with growth factor and integrin signalings in promoting cell adhesion in many cell types. This study is to explore if exogenous H2O2 at low levels can be beneficial to cell adhesion, migration, and wound healing.

METHODS. Primary rabbit corneal epithelial cells treated with 0–70 M H2O2 were tested for viability by MTT assay, adhesion by centrifugation assay, focal contacts of vinculin and F-actin by immunofluorescence, activated Src(pY416), EGF receptor (pY845), vinculin(pY1065), FAK(pY397), and FAK(pY576) by immunoblotting. Cell migration was examined with 0–50 M H2O2 using the scratch wound technique. Corneal …

Roles Of The 15-Kda Selenoprotein (Sep15) In Redox Homeostasis And Cataract Development Revealed By The Analysis Of Sep 15 Knockout Mice, Marina V. Kasaikina, Dmitri E. Fomenko, Vyacheslav M. Labunskyy, Salil A. Lachke, Wenya Qiu, Juliet A. Moncaster, Jie Zhang, Mark W. Wojnarowicz, Sathish Kumar Natarajan, Mikalai I. Malinouski, Ulrich Schweizer, Petra A. Tsuji, Bradley A. Carlson, Richard L. Maas, Marjorie F. Lou, Lee E. Goldstein, Dolph L. Hatfield, Vadim N. Gladyshev

School of Veterinary and Biomedical Sciences: Faculty Publications

The 15-kDa selenoprotein (Sep15) is a thioredoxin-like, endoplasmic reticulum-resident protein involved in the quality control of glycoprotein folding through its interaction with UDP-glucose:glycoprotein glucosyltransferase. Expression of Sep15 is regulated by dietary selenium and the unfolded protein response, but its specific function is not known. In this study, we developed and characterized Sep15 KO mice by targeted removal of exon 2 of the Sep15 gene coding for the cysteinerich UDP-glucose:glycoprotein glucosyltransferase-binding domain. These KO mice synthesized a mutant mRNA, but the shortened protein product could be detected neither in tissues nor in Sep15 KO embryonic fibroblasts. Sep15 KO mice were viable …

Arbovirus Phenotype Alters Transmission Potential, Rebecca C. Christofferson

LSU Doctoral Dissertations

Extrinsic and environmental factors are known to affect the transmission of arthropod-borne viruses (arboviruses), including variations in the arthropod vector populations. Differences among these factors have been associated with differential transmission and are sometimes used to control the spread of an arbovirus through a vertebrate population in an effort to prevent or disrupt an outbreak. However, diversity in intrinsic viral populations, such as genetic and phenotypic variability, is not often accounted for when considering alterations in transmission. Presented in this dissertation are four experimental studies that explore the contribution of viral intrinsic factors, especially phenotypic variability, to the transmission potential …

The Tick Response To Rickettsial Dissemination During Typical And Atypical Rickettsial Infection, Piyanate Sunyakumthorn

LSU Doctoral Dissertations

Ticks are the only disease vectors for spotted fever group (SFG) Rickettsia which are obligate intracellular bacteria belonging to the genus Rickettsia. In nature, ticks maintain the infection of SFG Rickettsia via vertical and horizontal transmission. However, the prevalence of rickettsial transmission is limited to certain species of ticks, and this limitation is known as a specific tick/Rickettsia relationship. Due to the continuous increase of tick-borne rickettsial disease cases in the United States, which contrasts with very low prevalence of Rickettsia in tick vectors, the study of vector competence of tick to Rickettsia is needed in order to understand the …

Mapping And Modeling Of Neglected Tropical Diseases In Brazil And Bolivia, Paula Mischler

LSU Doctoral Dissertations

Accurately defining disease distributions and calculating disease risk is an important step in the control and prevention of diseases. This study used geographical information systems and remote sensing technologies within the MaxEnt ecological niche modeling program to create predictive risk maps for leprosy and Schistosomiasis in Brazil and Chagas disease in both Brazil and Bolivia. New disease cases were compiled for leprosy, Schistosomiasis, and Chagas disease from the Brazilian ministry of Health for 2001 to 2009 and the data was stratified to a 10,000 population for each municipality. Bolivian Chagas prevalence rates were calculated from 2007 to 2009 survey data. …

Development, Optimization, And Validation Of A Classical Swine Fever Virus Real-Time Reverse Transcription Polymerase Chain Reaction Assay, August J. Eberling, Jill Bieker-Stefanelli, Monica M. Reising, David Siev, Barbara M. Martin, Michael T. Mcintosh, Tammy R. Beckham

Zoonotics and Wildlife Disease: Publications

Classical swine fever (CSF) is an economically devastating disease of pigs. Instrumental to the control of CSF is a well-characterized assay that can deliver a rapid, accurate diagnosis prior to the onset of clinical signs. A real-time fluorogenicprobe hydrolysis (TaqMan) reverse transcription polymerase chain reaction (RT-PCR) for CSF was developed by the United States Department of Agriculture (USDA) at the Plum Island Animal Disease Center (CSF PIADC assay) and evaluated for analytical and diagnostic sensitivity and specificity. A well-characterized panel including Classical swine fever virus (CSFV), Bovine viral diarrhea virus (BVDV), and Border disease virus (BDV) isolates was utilized in …

Carbenoxolone Blocks The Light-Evoked Rise In Intracellular Calcium In Isolated Melanopsin Ganglion Cell Photoreceptors, Jayne R. Bramley, Erin M. Wiles, Patricia J. Sollars, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Retinal ganglion cells expressing the photopigment melanopsin are intrinsically photosensitive (ipRGCs). These ganglion cell photoreceptors send axons to several central targets involved in a variety of functions. Within the retina ipRGCs provide excitatory drive to dopaminergic amacrine cells via glutamatergic signals and ipRGCs are coupled to widefield GABAergic amacrine cells via gap junctions. However, the extent to which ipRGCs are coupled to other retinal neurons in the ganglion cell layer via gap junctions is unclear. Carbenoxolone, a widely employed gap junction inhibitor, greatly reduces the number of retinal neurons exhibiting non-rod, non-cone mediated light-evoked Ca²⁺ signals suggesting extensive …

Y-Like Retinal Ganglion Cells Innervate The Dorsal Raphe Nucleus In The Mongolian Gerbil (Meriones Unguiculatus), Liju Luan, Chaoran Ren, Benson Wui-Man Lau, Jian Yang, Gary E. Pickard, Kwok-Fai So, Mingliang Pu

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: The dorsal raphe nucleus (DRN) of the mesencephalon is a complex multi-functional and multi-transmitter nucleus involved in a wide range of behavioral and physiological processes. The DRN receives a direct input from the retina. However little is known regarding the type of retinal ganglion cell (RGC) that innervates the DRN. We examined morphological characteristics and physiological properties of these DRN projecting ganglion cells.

Methodology/Principal Findings: The Mongolian gerbils are highly visual rodents with a diurnal/crepuscular activity rhythm. It has been widely used as experimental animals of various studies including seasonal affective disorders and depression. Young adult gerbils were used …

Challenges And Opportunities For Toxicology In Mexico, Rodrigo Franco, Balam Muñoz

School of Veterinary and Biomedical Sciences: Faculty Publications

We have developed this Special Issue titled “Challenges and Opportunities for Toxicology in Mexico” with the aim to highlight not only the challenges toxicology research faces in Mexico, but also the efforts and drive towards cutting edge research to address them. Altogether, this special issue should be a valuable source of information for all readers with an interest in toxicology and human health.

Mexico is an important economy worldwide and is a major exporter of several supplies and commodities. Because of this, its industry is a source of occupational exposure to several chemical derivatives (Nieusma 2011). The situation of occupational …

Intrinsically Photosensitive Retinal Ganglion Cells, Gary E. Pickard, Patricia J. Sollars

School of Veterinary and Biomedical Sciences: Faculty Publications

Intrinsically photosensitive retinal ganglion cells (ipRGCs) respond to light in the absence of all rod and cone photoreceptor input. The existence of these ganglion cell photoreceptors, although predicted from observations scattered over many decades, was not established until it was shown that a novel photopigment, melanopsin, was expressed in retinal ganglion cells of rodents and primates. Phototransduction in mammalian ipRGCs more closely resembles that of invertebrate than vertebrate photoreceptors and appears to be mediated by transient receptor potential channels. In the retina, ipRGCs provide excitatory drive to dopaminergic amacrine cells and ipRGCs are coupled to GABAergic amacrine cells via gap …

Long-Term Clinicopathological Characteristics Of Alpacas Naturally Infected With Bovine Viral Diarrhea Virus Type Ib, D. Bedenice, Edward J. Dubovi, Clayton Kelling, Jamie N Henningson, Christina L. Topliff, N. Parry

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Substantial bovine viral diarrhea virus (BVDV)-related production losses in North American alpaca herds have been associated with BVDV type Ib infection.

Objectives: To classify and differentiate the long-term clinicopathological characteristics of BVDV type Ib infection of al- paca crias, after natural virus exposure. We hypothesized that persistently infected (PI) alpacas specifically demonstrate growth retardation, clinicopathological evidence of opportunistic infections, and early mortality.

Animals: Thirty-five crias naturally exposed to BVDV (18 acute, 3 chronic, 14 PIs), and 19 healthy cohort controls of 5 northeastern alpaca farms were prospectively evaluated over 2 years (September 2005–September 2008).

Methods: Observational cohort-control study.

Results: …

Rnai Screening Reveals Requirement For Host Cell Secretory Pathway In Infection By Diverse Families Of Negative-Strand Rna Viruses, Debasis Panda, Anshuman Das, Phat X. Dinh, Sakthivel Subramaniam, Debasis Nayak, Nicholas J. Barrows, James L. Pearson, Jesse Thompson, David L. Kelly, Istvan Ladunga, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Negative-strand (NS) RNA viruses comprise many pathogens that cause serious diseases in humans and animals. Despite their clinical importance, little is known about the host factors required for their infection. Using vesicular stomatitis virus (VSV), a prototypic NS RNA virus in the family Rhabdoviridae, we conducted a human genomewide siRNA screen and identified 72 host genes required for viral infection. Many of these identified genes were also required for infection by two other NS RNA viruses, the lymphocytic choriomeningitis virus of the Arenaviridae family and human parainfluenza virus type 3 of the Paramyxoviridae family. Genes affecting different stages of …

Consensus-Based Reporting Standards For Diagnostic Test Accuracy Studies For Paratuberculosis In Ruminants, Ian A. Gardner, Søren S. Nielsen, Richard J. Wittington, Michael T. Collins, Douwe Bakker, Beth Harris, Srinand Sreevatsan, Jason E. Lombard, Raymond Sweeney, David R. Smith, Jerrie Gavalchin, Shigetoshi Eda

School of Veterinary and Biomedical Sciences: Faculty Publications

The Standards for Reporting of Diagnostic Accuracy (STARD) statement was developed to encourage complete and transparent reporting of key elements of test accuracy studies in human medicine. The statement was motivated by widespread evidence of bias in test accuracy studies and the finding that incomplete or absent reporting of items in the STARD checklist was associated with overly optimistic estimates of test performance characteristics. Although STARD principles apply broadly, specific guidelines do not exist to account for unique considerations in livestock studies such as herd tests, potential use of experimental challenge studies, a more diverse group of testing purposes and …

Characterization Of Spiroplasma Mirum And Its Role In Transmissible Spongiform Encephalopathies, Hilari Maree French

LSU Doctoral Dissertations

There are many contradictory reports in the literature involving the culture of Spiroplasma mirum, its resistance to disinfectants and antibiotics, and its potential role in Transmissible Spongiform Encephalopathies (TSEs). These contradictions led to an interest in a possible link between spiroplasma and TSEs and the development of a research plan to elucidate this connection. It was hypothesized that Spiroplasma was associated with a neurodegenerative disease such as TSE. In this work we further characterized S. mirum laboratory strains and continued to evaluate the possible correlations they have with TSE infections and the prion. To optimize recovery of S. mirum from …

Arginine Metabolism In The Edwardsiella Ictaluri- Channel Catfish Macrophage Dynamic, Wes Arend Baumgartner

LSU Doctoral Dissertations

Edwardsiella ictaluri encodes a urease operon and an arginine decarboxylase (AdiA) that are required for virulence in head kidney derived macrophages (HKDM). The urease produces ammonia in amounts sufficient to alter environmental pH from acid to neutral. A hypothetical model was proposed, involving arginine metabolism in E. ictaluri infected HKDM, focusing on bacterial urease, AdiA, a second arginine decarboxylase (SpeA), and agmatinase (SpeB). Using fluorescence based ratiometric pH determination of E. ictaluri in live HKDM, it was shown that E. ictaluri modulates HKDM phagosome pH to above six. Urease and AdiA mutants failed to up-regulate vacuole pH, while vacuole pH …

Importance Of Wildlife Disease Surveillance, Jerrold L. Belant, Amanda R. Deese

Human–Wildlife Interactions

A commentary on the importance of wildlife disease surveillance.

The Lack Of An Inherent Membrane Targeting Signal Is Responsible For The Failure Of The Matrix (M1) Protein Of Influenza A Virus To Bud Into Virus-Like Particles, Dan Wang, Aaron Harmon, Jing Jin, David H. Francis, Jane Christopher-Hennings, Eric A. Nelson, Ronald C. Montelaro, Feng Li

Veterinary and Biomedical Sciences Faculty Publications

The matrix protein (M1) of influenza A virus is generally viewed as a key orchestrator in the release of influenza virions from the plasma membrane during infection. In contrast to this model, recent studies have indicated that influenza virus requires expression of the envelope proteins for budding of intracellular M1 into virus particles. Here we explored the mechanisms that control M1 budding. Similarly to previous studies, we found that M1 by itself fails to form virus-like-particles (VLPs). We further demonstrated that M1, in the absence of other viral proteins, was preferentially targeted to the nucleus/perinuclear region rather than to the …

Spontaneous Feline Mammary Intraepithelial Lesions As A Model For Human Estrogen Receptor- And Progesterone Receptor-Negative Breast Lesions, Giovanni P. Burrai, Sulma Mohammed, Margaret A. Miller, Vincenzo Marras, Salvatore Pirino, Maria F. Addis, Sergio Uzzau, Elisabetta Antuofermo

Department of Comparative Pathobiology Faculty Publications

Background: Breast cancer is the most frequently diagnosed cancer in women. Intraepithelial lesions (IELs), such as usual ductal hyperplasia (UH), atypical ductal hyperplasia (ADH), and ductal carcinoma in situ (DCIS) are risk factors that predict a woman’s chance of developing invasive breast cancer. Therefore, a comparative study that establishes an animal model of pre-invasive lesions is needed for the development of preventative measures and effective treatment for both mammary IELs and tumors. The purpose of this study was to characterize the histologic and molecular features of feline mammary IELs and compare them with those in women. Methods: Formalin-fixed, paraffin-embedded specimens …

Role Of All Of The Prrsv Glycoproteins In Protective Immune Response, Asit K. Pattnaik

School of Veterinary and Biomedical Sciences: Faculty Publications

Porcine reproductive and respiratory syndrome virus (PRRSV) contains the major glycoprotein, GP5, as well as three other minor glycoproteins, namely, GP2a, GP3, and GP4, on the virion envelope, all of which are required for generation of infectious virions. To study their interactions amongst each other and with the cellular receptor for PRRSV, we have cloned each of the viral glycoproteins and CD163 receptor in expression vectors and examined their expression and interaction with each other in transfected cells by co-immunoprecipitation (co-IP) assay using monospecific antibodies. Our results show that strong interaction exists between GP4 and GP5 proteins, although weak interactions …

Cell-Type Specific Distribution Of Chloride Transporters In The Rat Suprachiasmatic Nucleus, Michael A. Belenky, Patricia J. Sollars, David B. Mount, Seth L. Alper, Yosef Yarom, Gary E. Pickard

School of Veterinary and Biomedical Sciences: Faculty Publications

The suprachiasmatic nucleus (SCN) is a circadian oscillator and biological clock. Cell-to-cell communication is important for synchronization among SCN neuronal oscillators and the great majority of SCN neurons use γ-aminobutyric acid (GABA) as a neurotransmitter, the principal inhibitory neurotransmitter in the adult central nervous system. Acting via the ionotropic GABAA receptor, a chloride ion channel, GABA typically evokes inhibitory responses in neurons via Cl− influx. Within the SCN GABA evokes both inhibitory and excitatory responses although the mechanism underlying GABA-evoked excitation in the SCN is unknown. GABA-evoked depolarization in immature neurons in several regions of the brain is a function …