Veterinary Microbiology and Immunobiology Commons^™

Histological Findings In Free-Ranging Sarasota Bay Bottlenose Dolphin (Tursiops Truncatus) Skin: Mercury, Selenium, And Seasonal Factors., Debra Miller, V. Woshner, E. Styer, S. Ferguson, K. Knott, Matthew Gray, R. Wells, T. O'Hara

Debra L Miller

Full-thickness epidermal biopsy samples were collected from free-ranging common bottlenose dolphins (Tursiops truncatus) in Sarasota Bay, Florida, USA. Season (summer or winter) of collection, mercury (Hg) concentration, and selenium (Se) concentration were compared to histologic parameters. Epidermal Hg concentration was positively related to age (P<0.001) and negatively related to height of the stratum spinosum (P<0.05). The mitotic index and heights of the stratum externum and intermedium were lower in summer than in winter (P<0.01). Transmission electron microscopic examination revealed variation in the diameters (60–138 nm) and arrangements of collagen fibers, regardless of age ...

Differential Induction Of Reactive Oxygen Species Through Erk1/2 And Nox-1 By Fk228 For Selective Apoptosis Of Oncogenic H-Ras-Expressing Human Urinary Bladder Cancer J82 Cells, Shambhunath Choudhary, Kusum Rathore, H. Wang

Shambhunath Choudhary DVM, PhD

PURPOSE: This study sought to reveal mechanisms for differential regulation of reactive oxygen species (ROS) in histone deacetylase inhibitor FK228-induced selective apoptosis of oncogenic H-Ras-expressing human cancer cells.

METHODS: Human urinary bladder cancer J82 and oncogenic H-Ras-expressing J82 cells were used to reveal FK228-induced differential Erk1/2 activation, Nox-1 elevation, ROS production, glutathione (GSH) depletion, caspase activation, and apoptosis. Specific inhibitors were used to suppress Nox-1 activity and ROS production. Mek1/2 inhibitor was used to suppress Erk1/2 activation. Validated-specific siRNAs were used to knock down Nox-1. ROS levels, GSH levels, and caspase-3/7 activities were measured by GSH ...

Reactive Oxygen Species-Mediated Therapeutic Control Of Bladder Cancer., Shambhunath Choudhary, Hwa-Chain Wang

Shambhunath Choudhary DVM, PhD

Urinary bladder cancer is the fifth most common cancer in the US and the most costly cancer to manage because it requires life-long surveillance to monitor for recurrence and advanced progression. Urothelial carcinomas account for more than 90% of urinary bladder cancer cases. Transurethral resection and intravesical chemotherapy or immunotherapy are effective short-term treatments of urothelial carcinoma, but long-term management has not yet been optimized. Recent therapeutic strategies emphasize the targeted interference with aberrantly-regulated signaling modulators that result from genomic alterations. However, targeted therapeutic agents might not distinguish cancer cells from their normal counterparts, resulting in undesirable adverse effects. Thus ...

Intersex Condition Of Shoal Bass In The Flint River, Georgia., D. Ingram, Debra Miller, T. Ingram, J. Tannehill

Debra L Miller

We examined male shoal bass Micropterus cataractae from the Flint River, Georgia, to determine the prevalence of intersex. During March and April 2010, we sampled 61 shoal bass from six sites along the Flint River. Testes were examined histologically and classified as intersex if the presence of oocytes was noted. Using a severity index, we compared samples collected on different dates and from different locations according to age and testis weight. No significant variations were noted among any of the groupings. Further investigation is needed to determine whether the intersex condition in shoal bass is severe enough to warrant concern ...

Phylogeny, Life History, And Ecology Contribute To Differences In Amphibian Susceptibility To Ranaviruses., J. Hoverman, Matthew Gray, Nathan Haislip, Debra Miller

Debra L Miller

Research that identifies the potential host range of generalist pathogens as well as variation in host susceptibility is critical for understanding and predicting the dynamics of infectious diseases within ecological communities. Ranaviruses have been linked to amphibian die-off events worldwide with the greatest number of reported mortality events occurring in the United States. While reports of ranavirus-associated mortality events continue to accumulate, few data exist comparing the relative susceptibility of different species. Using a series of laboratory exposure experiments and comparative phylogenetics, we compared the susceptibilities of 19 amphibian species from two salamander families and five anurans families for two ...

Differential Induction Of Reactive Oxygen Species Through Erk1/2 And Nox-1 By Fk228 For Selective Apoptosis Of Oncogenic H-Ras-Expressing Human Urinary Bladder Cancer J82 Cells, Shambhunath Choudhary, Kusum Rathore, Hwa-Chain Wang

Kusum Rathore MS, PhD, College of Veterinary Medicine

More than 35% of human urinary bladder cancers involve oncogenic H-Ras activation. The goal of this study was to investigate the role of the ERK pathway in mediating apoptotic signals induced by oncogenic H-Ras, FK228 treatment, and exogenous H(2) O(2) treatment to increase Nox-1 elevation, leading to production of intracellular reactive oxygen species (ROS) for inducing apoptosis in human bladder cancer J82 cells. Our study revealed that FK228 combined with exogenous H(2)O(2) cooperatively induced activation of Mek1/2 and Erk1/2 to increase Nox-1 elevation, intracellular ROS production, caspase activation, and cell death. Expression of ...

Ecopathology Of Ranaviruses Infecting Amphibians., Debra Miller, Matthew Gray, A. Storfer

Debra L Miller

Ranaviruses are capable of infecting amphibians from at least 14 families and over 70 individual species. Ranaviruses infect multiple cell types, often culminating in organ necrosis and massive hemorrhaging. Subclinical infections have been documented, although their role in ranavirus persistence and emergence remains unclear. Water is an effective transmission medium for ranaviruses, and survival outside the host may be for significant duration. In aquatic communities, amphibians, reptiles and fish may serve as reservoirs. Controlled studies have shown that susceptibility to ranavirus infection and disease varies among amphibian species and developmental stages, and likely is impacted by host-pathogen coevolution, as well ...

Detection Of Human Papillomavirus Dna In Feline Premalignant And Invasive Squamous Cell Carcinoma, Sh O'Neill, Kim Newkirk, Ea Anis, R Brahmbhatt, La Frank, Stephen Kania

Stephen A Kania

No abstract provided.

Streptococcus Phocae Isolated From A Spotted Seal ( Phoca Largha) With Pyometra In Alaska., K. Hueffer, C. Lieske, L. Mcgilvary, R. Hare, Debra Miller, T. O'Hara

Debra L Miller

A spotted seal harvested by subsistence hunters in Kotzebue Sound, Alaska (USA), showed a grossly enlarged uterus and associated lymph nodes. Streptococcus phocae was isolated from the purulent uterine discharge. Histopathologic examination revealed inflammation that was limited to the uterine mucosa. Lymph nodes draining the affected organ were reactive but no evidence of active infection was found in the lymph nodes. This report is the first Streptococcus phocae isolated from spotted seals as well as the first report of pyometra as the main pathologic finding associated with this pathogen. Isolation of this pathogen from Alaska expands the reported range to ...

Development Of An In Vivo Rnai Protocol To Investigate Gene Function In The Filarial Nematode, Brugia Malayi, Chuanzhe Song, Jack M. Gallup, Timothy A. Day, Lyric C. Bartholomay, Michael J. Kimber

Entomology Publications

Our ability to control diseases caused by parasitic nematodes is constrained by a limited portfolio of effective drugs and a paucity of robust tools to investigate parasitic nematode biology. RNA interference (RNAi) is a reverse-genetics tool with great potential to identify novel drug targets and interrogate parasite gene function, but present RNAi protocols for parasitic nematodes, which remove the parasite from the host and execute RNAi in vitro, are unreliable and inconsistent. We have established an alternative in vivo RNAi protocol targeting the filarial nematode Brugia malayi as it develops in an intermediate host, the mosquito Aedes aegypti. Injection of ...

Sensitivity And Specificity Of A Nested Polymerase Chain Reaction For Detection Of Lentivirus Infection In Lions (Panthera Leo), H Adams, M Van Vuuren, Stephen Kania, A Bosman, D Keet, J New, Melissa Kennedy

Melissa A. Kennedy

Feline immunodeficiency virus (FIV) is a lentivirus in the Retroviridae family that causes lifelong infection in domestic cats. The lentivirus of African lions (Panthera leo), referred to as FIVple, is endemic in certain lion populations in eastern and southern Africa. Lentivirus infection leads to immunologic dysfunction and immunosuppressive disease in domestic cats; however, little is known about the pathogenic effects of infection in lions, nor about the epidemiologic impact on free-ranging and captive populations. Whole blood and serum samples were collected opportunistically from free-ranging lions in Kruger National Park, Republic of South Africa (RSA). Whole blood and serum samples were ...

Efficacy Of A Doxycycline Treatment Regimen Initiated During Three Different Phases Of Experimental Ehrlichiosis, Jennifer C. Mcclure, Michelle L. Crothers, John J. Schaefer, Patrick D. Stanley, Glen R. Needham, S A. Ewing, Roger W. Stich

John J Schaefer

Doxycycline is the treatment of choice for canine monocytic ehrlichiosis (CME), a well-characterized disease and valuable model for tick-borne zoonoses. Conflicting reports of clearance of Ehrlichia canis after treatment with doxycycline suggested that the disease phase during which treatment is initiated influences outcomes of these treatments. The purpose of this study was to evaluate the efficacy of a 28-day doxycycline regimen for clearance of experimental E. canis infections from dogs treated during three phases of the disease. Ten dogs were inoculated with blood from E. canis carriers and treated with doxycycline during acute, subclinical, or chronic phases of CME. Daily ...

Detection Of Flaviviruses And Orthobunyaviruses In Mosquitoes In The Yucatan Peninsula Of Mexico In 2008, Jose A. Farfan-Ale, Maria A. Loroño-Pino, Julian E. Garcia-Rejon, Victor Soto, Ming Lin, Molly Staley, Karin S. Dorman, Lyric C. Bartholomay, Einat Hovav, Bradley J. Blitvich

Entomology Publications

A total of 191,244 mosquitoes from 24 species were collected in the Yucatan Peninsula of Mexico from January to December 2008, and tested for the presence of cytopathic virus by virus isolation in Vero cells. Eighteen virus isolates were obtained, all of which were orthobunyaviruses. These were identified by reverse transcription-polymerase chain reaction (RT-PCR) and nucleotide sequencing as Cache Valley virus (n = 17) and South River virus (n = 1). A subset (n = 20,124) of Culex quinquefasciatus collected throughout the year was further tested by RT-PCR using flavivirus-specific primers. Flavivirus RNA was present in this mosquito species year-round. The ...

Methicillin Resistance In Staphylococcus Pseudintermedius, Chad Christopher Black

Doctoral Dissertations

Staphylococcus pseudintermedius affecting dogs is analogous to S. aureus on humans, acting as both normal flora and opportunistic pathogen. Methicillin resistance in S. pseudintermedius is recent, with the first documented occurrence of an isolate bearing the methicillin resistance gene, mecA, in 1999. This gene encodes penicillin binding protein 2a, which renders all beta-lactam drugs ineffective and functions as a “gateway” antibiotic resistance determinant. In the presence of ineffective antibiotics, opportunities for mutational events and acquisition of mobile genetic elements increase as microbial densities increase, often leading to multi-drug resistance. Methicillin-resistant S. pseudintermedius (MRSP) infections have become increasingly common. For example ...

Avian-Pathogenic Escherichia Coli Strains Are Similar To Neonatal Meningitis E. Coli Strains And Are Able To Cause Meningitis In The Rat Model Of Human Disease, Kelly A. Tivendale, Catherine M. Logue, Subhashinie Kariyawasam, Dianna Jordan, Ashraf Hussein, Ganwu Li, Yvonne Wannemuehler, Lisa K. Nolan

Veterinary Microbiology and Preventive Medicine Publications

Escherichia coli strains causing avian colibacillosis and human neonatal meningitis, urinary tract infections, and septicemia are collectively known as extraintestinal pathogenic E. coli (ExPEC). Characterization of ExPEC strains using various typing techniques has shown that they harbor many similarities, despite their isolation from different host species, leading to the hypothesis that ExPEC may have zoonotic potential. The present study examined a subset of ExPEC strains: neonatal meningitis E. coli (NMEC) strains and avian-pathogenic E. coli(APEC) strains belonging to the O18 serogroup. The study found that they were not easily differentiated on the basis of multilocus sequence typing, phylogenetic typing ...

Differential Splenic Cytokine Responses To Dietary Immune Modulation By Diverse Chicken Lines, S. B. Redmond, R. M. Tell, D. Coble, C. Mueller, D. Palić, Claire B. Andreasen, Susan J. Lamont

Animal Science Publications

Nutritional modulation of the immune system is an often exploited but poorly characterized process. In chickens and other food production animals, dietary enhancement of the immune response is an attractive alternative to antimicrobial use. A yeast cell wall component, β-1,3/1,6-glucan, augments the response to disease in poultry and other species; however, the mechanism of action is not clear. Ascorbic acid and corticosterone are better characterized immunomodulators. In chickens, the spleen acts both as reservoir and activation site for leukocytes and, therefore, splenic gene expression reflects systemic immune function. To determine effects of genetic line and dietary immunomodulators ...

Molecular Analysis Of Methicillin-Resistant Staphylococcus Pseudintermedius Of Feline Origin From Different European Countries And North America, K Kaldec, S Schwarz, V Perreten, U Andersson, M Finn, C Greko, A Moodley, Stephen Kania, L Frank, D Bemis, A Franco, M Iurescia, A Battisti, B Duim, J Wagenaar, E Van Duijkeren, J Weese, J Fitzgerald, A Rossano, L Guardabassi

Stephen A Kania

No abstract provided.

Innate Immunology Of Bovine Respiratory Disease, Mark R. Ackermann, Rachel Derscheid, James A. Roth

Veterinary Microbiology and Preventive Medicine Publications

Pneumonia is a leading cause of loss to the cattle industry in the United States and Europe. Of cattle diseases, it has the greatest economic impact. Respiratory pathogens can cause serious outbreaks of acute pneumonia in neonatal, weaned and growing calves. Chronic infection leads to debilitation, decreased performance, and culling in older animals. The means to enhance effective and non-injurious immune responses are needed because of the high incidence of pneumonia in cattle, ubiquity of respiratory pathogens, the increasing frequency of antibiotic resistance, and the general expectation by consumers for producers to use antibiotics less frequently. The lung has a ...

Genome-Wide Transposon Mutagenesis Reveals A Role For Po157 Genes In Biofilm Development In Escherichia Coli O157:H7 Edl933, Supraja Puttamreddy, Nancy A. Cornick, F. Chris Minion

Veterinary Microbiology and Preventive Medicine Publications

Enterohemorrhagic Escherichia coli O157:H7, a world-wide human food-borne pathogen, causes mild to severe diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome. The ability of this pathogen to persist in the environment contributes to its dissemination to a wide range of foods and food processing surfaces. Biofilms are thought to be involved in persistence, but the process of biofilm formation is complex and poorly understood in E. coli O157:H7. To better understand the genetics of this process, a mini-Tn5 transposon insertion library was constructed in strain EDL933 and screened for biofilm-negative mutants using a microtiter plate assay. Ninety-five of ...

Clonal Spread Of Methicillin-Resistant Staphylococcus Pseudintermedius In Europe And North America: An International Multicentre Study, V Perreten, K Kadlec, S Schwarz, U Grönlund Andersson, M Finn, C Greko, A Moodley, Stephen Kania, L Frank, D Demis, A Franco, M Iurescia, A Battisti, B Duim, J Wagenaar, E Van Duijkeren, J Weese, J Fitzgerald, A Rossano, L Guardabassi

Stephen A Kania

OBJECTIVES: The aim of this study was to determine the phenotypic and genotypic resistance profiles of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and to examine the clonal distribution in Europe and North America. METHODS: A total of 103 MRSP isolates from dogs isolated from several countries in Europe, the USA and Canada were characterized. Isolates were identified by PCR-restriction fragment length polymorphism (RFLP), antimicrobial susceptibility was determined by broth dilution or gradient diffusion, and antimicrobial resistance genes were detected using a microarray. Genetic diversity was assessed by multilocus sequence typing (MLST), PFGE and spa typing. Staphylococcal cassette chromosome mec (SCCmec) elements were ...