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34.29
Research experience
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Jul 2002–
presentResearch: University of Florida
University of Florida · Department of Small Animal Clinical SciencesUSA · Gainesville -
Jun 2001
Research: University of Guelph
University of GuelphCanada · Guelph -
Jan 1997–
May 2001Research: University of Minnesota
University of Minnesota Twin Cities · College of Veterinary MedicineUSA · St. Paul
Publications (91) View all
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Article: Renal infection by a new coccidian genus in big brown bats (Eptesicus fuscus).
Arno Wünschmann, James F X Wellehan, Anibal Armien, William J Bemrick, Donald Barnes, Gary A Averbeck, Richard Roback, Marc Schwabenlander, Edgar D'Almeida, Ron Joki, April L Childress, Roberto Cortinas, Chris H Gardiner, Ellis C Greiner[show abstract] [hide abstract]
ABSTRACT: A novel coccidian parasite from the kidney of big brown bats (Eptesicus fuscus) is described. This coccidian (Nephroisospora eptesici nov. gen., n. sp.) was associated with a generally mild, focal or multifocal, well-demarcated cortical renal lesion less than 1 mm in diameter. The lesion represented cystic, dilated tubules with hypertrophied tubular epithelial cells and was present in the kidneys of 29 of 590 bats. Numerous coccidian parasites in various stages of development were present within the tubular epithelial cells and within the cyst lumina. Oocysts were collected from cystic dilated tubules. Thin-walled, sporulated ellipsoidal oocysts measuring an average of 18.9 x 20.8 microm were present in kidney tissue. The oocysts contained 2 sporocysts with 4 sporozoites. A polar body and a prominent oocyst residuum were present in the oocysts, but no micropyle, sporocyst residuum, or Stieda bodies were detected. Analysis of the 18S rRNA gene sequence put the parasite in the Sarcocystidae. The parasite is closely related to Besnoitia, Hammondia, Neospora, and Toxoplasma. Ultrastructural features, such as the presence of an apical complex in merozoites, support the identification of a coccidian. A new genus and species, Nephroisospora eptesicii, is proposed for this unusual coccidian in which the entire cycle is completed in the kidney of a single host; it has a membrane-like oocyst wall, sporogony occurs in the host rather than in the abiotic environment, and the positioning of the parasite by nucleic acid sequence indicates it to be closely allied to Sarcocystis and Besnoitia.Journal of Parasitology 10/2009; 96(1):178-83. · 1.40 Impact Factor -
SourceAvailable from: James Wellehan
Article: Massive visceral pentastomiasis caused by Porocephalus crotali in a dog.
[show abstract] [hide abstract]
ABSTRACT: The testes of a 5-year-old, male, crossbred Schnauzer dog were the indicator organs for detection of massive pentastomiasis. Necropsy revealed numerous additional encysted parasites within the mesenteric lymph nodes, omentum, liver, sub-serosa of the small and large intestines, mesentery, and lungs. The nymphs had a pseudosegmented body, containing large eosinophilic glands and a chitinous cuticle with characteristic pores. Their hook configuration was consistent with that of Porocephalus. A pentastomid-specific 18S rRNA polymerase chain reaction (PCR) was designed and used to amplify template for sequencing. The sequence of the PCR product was 99.7% homologous with the reference sequence for P. crotali. This pentastomid parasite has been reported in North American snakes of genera Crotalus and Agkistrodon. Mammals are intermediate hosts, and snakes are the definitive hosts. Porocephalus crotali has been reported in dogs only once, and molecular methods have not been used previously to identify the species in clinical pentastomiasis.Veterinary Pathology 02/2009; 46(3):460-3. · 1.95 Impact Factor -
Article: Partial characterization of a new adenovirus lineage discovered in testudinoid turtles.
Andor Doszpoly, James F X Wellehan Jr, April L Childress, Zoltán L Tarján, Endre R Kovács, Balázs Harrach, Mária Benkő[show abstract] [hide abstract]
ABSTRACT: In the USA and in Hungary, almost simultaneously, adenoviruses of a putative novel lineage were detected by PCR and sequencing in turtles belonging to four different species (including two subspecies) of the superfamily Testudinoidea. In the USA, partial sequence of the adenoviral DNA-dependent DNA polymerase was obtained from samples of a captive pancake tortoise (Malacochersus tornieri), four eastern box turtles (Terrapene carolina carolina) and two red-eared sliders (Trachemys scripta elegans). In Hungary, several individuals of the latter subspecies as well as some yellow-bellied sliders (T. s. scripta) were found to harbor identical, or closely related, putative new adenoviruses. From numerous attempts to amplify any other genomic fragment by PCR, only a nested method was successful, in which a 476-bp fragment of the hexon gene could be obtained from several samples. In phylogeny reconstructions, based on either DNA polymerase or hexon partial sequences, the putative new adenoviruses formed a clade distinct from the five accepted genera of the family Adenoviridae. Three viral sub-clades corresponding to the three host genera (Malacochersus, TerrapeneTrachemys) were observed. Attempts to isolate the new adenoviruses on turtle heart (TH-1) cells were unsuccessful. Targeted PCR screening of live and dead specimens revealed a prevalence of approximately 25% in small shelter colonies of red-eared and yellow-bellied sliders in Hungary. The potential pathology of these viruses needs further investigation; clinically healthy sliders were found to shed the viral DNA in detectable amounts. Based on the phylogenetic distance, the new adenovirus lineage seems to merit the rank of a novel genus.Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 04/2013; · 3.22 Impact Factor -
Article: A novel gammaherpesvirus in a large flying fox (Pteropus vampyrus) with blepharitis.
A Paige Brock, Galaxia Cortés-Hinojosa, Caryn E Plummer, Julia A Conway, Shannon R Roff, April L Childress, James F X Wellehan[show abstract] [hide abstract]
ABSTRACT: A novel gammaherpesvirus was identified in a large flying fox (Pteropus vampyrus) with conjunctivitis, blepharitis, and meibomianitis by nested polymerase chain reaction and sequencing. Polymerase chain reaction amplification and sequencing of 472 base pairs of the DNA-dependent DNA polymerase gene were used to identify a novel herpesvirus. Bayesian and maximum likelihood phylogenetic analyses indicated that the virus is a member of the genus Percavirus in the subfamily Gammaherpesvirinae. Additional research is needed regarding the association of this virus with conjunctivitis and other ocular pathology. This virus may be useful as a biomarker of stress and may be a useful model of virus recrudescence in Pteropus spp.Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 04/2013; · 1.21 Impact Factor -
SourceAvailable from: James Wellehan
Article: A novel gammaherpesvirus found in oral squamous cell carcinomas in sun bears (Helarctos malayanus).
Lydia Lam, Michael M Garner, Christine L Miller, Victoria E Milne, Kimberly A Cook, Gary Riggs, James F Grillo, April L Childress, James F X Wellehan[show abstract] [hide abstract]
ABSTRACT: A novel herpesvirus was detected in sun bears (Helarctos malayanus) with oral squamous cell carcinoma. Five captive sun bears from 4 institutions in the United States presented with oral lesions ranging from erythema and mild erosions to nodular, ulcerated masses. All 5 were diagnosed with squamous cell carcinoma. The tumors were treated with surgical resection but recurrence, local extension, or appearance of new lesions was noted in all cases. Intralesional chemotherapy was administered in 2 cases, and the nonsteroidal anti-inflammatory drug piroxicam was administered in 3 cases. Virus was detected in 4 of the 5 bears' tissue samples using a consensus herpesvirus polymerase chain reaction. Nucleotide sequencing and phylogenetic analysis showed that this herpesvirus is in the subfamily Gammaherpesvirinae and distinct from other known herpesviruses. The association between the herpesvirus and squamous cell carcinoma is unknown. The current study presents a novel gammaherpesvirus within the order Ursidae, with the name Ursid herpesvirus 1 proposed.Journal of veterinary diagnostic investigation: official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc 01/2013; 25(1):99-106. · 1.21 Impact Factor