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Critical Comment: What We Don’T Recognize Can Hurt Us: A Plea For Awareness About Cryptic Species, Gerardo Pérez-Ponce De León, Steven A. Nadler Jan 2010

Critical Comment: What We Don’T Recognize Can Hurt Us: A Plea For Awareness About Cryptic Species, Gerardo Pérez-Ponce De León, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

We conducted an extensive literature review on studies that have used DNA sequences to detect cryptic species of parasites during the last decade. Each literature citation that included the term ‘‘cryptic’’ or ‘‘sibling’’ species was analyzed to determine the approach used by the author(s). Reports were carefully filtered to retain only those that recognized the existence of cryptic species centered on the use of DNA sequences. Based on analysis of these papers, we comment on the different ways that parasite cryptic species are discovered in studies focusing on different aspects of the host–parasite relationship, or disciplines, within parasitology. We found …


Chloroquine Susceptibility And Reversibility In A Plasmodium Falciparum Genetic Cross, Jigar J. Patel, Drew Thacker, John C. Tan, Perri Pleeter, Lisa Checkley, Joseph M. Gonzales, Bingbing Deng, Paul D. Roepe, Roland A. Cooper, Michael T. Ferdig Jan 2010

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

Biological Sciences Faculty Publications

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 x Dd2 cross, we show that the P. falciparum multidrug resistance gene 1 (pfmdr1) interacts with the South-East Asia-derived mutant pfcrt haplotype to modulate CQR levels. A novel chromosome 7 locus is predicted to contribute …


How Birds Combat Ectoparasites, Dale H. Clayton, Jennifer A. H. Koop, Christopher W. Harbison, Brett R. Moyer, Sarah E. Bush Jan 2010

How Birds Combat Ectoparasites, Dale H. Clayton, Jennifer A. H. Koop, Christopher W. Harbison, Brett R. Moyer, Sarah E. Bush

Harold W. Manter Laboratory of Parasitology: Library Materials

Birds are plagued by an impressive diversity of ectoparasites, ranging from feather-feeding lice, to feather-degrading bacteria. Many of these ectoparasites have severe negative effects on host fitness. It is therefore not surprising that selection on birds has favored a variety of possible adaptations for dealing with ectoparasites. The functional significance of some of these defenses has been well documented. Others have barely been studied, much less tested rigorously. In this article we review the evidence--or lack thereof--for many of the purported mechanisms birds have for dealing with ectoparasites. We concentrate on features of the plumage and its components, as well …


Phylogenetic Position Of The Acariform Mites: Sensitivity To Homology Assessment Under Total Evidence, Almir R. Pepato, Carlos E. F. Da Rocha, Jason A. Dunlop Jan 2010

Phylogenetic Position Of The Acariform Mites: Sensitivity To Homology Assessment Under Total Evidence, Almir R. Pepato, Carlos E. F. Da Rocha, Jason A. Dunlop

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: Mites (Acari) have traditionally been treated as monophyletic, albeit composed of two major lineages: Acariformes and Parasitiformes. Yet recent studies based on morphology, molecular data, or combinations thereof, have increasingly drawn their monophyly into question. Furthermore, the usually basal (molecular) position of one or both mite lineages among the chelicerates is in conflict to their morphology, and to the widely accepted view that mites are close relatives of Ricinulei.

Results: The phylogenetic position of the acariform mites is examined through employing SSU, partial LSU sequences, and morphology from 91 chelicerate extant terminals (forty Acariformes). In a static homology framework, …


Genbank, Dennis A. Benson, Ilene Karasch-Mizrachi, David J. Lipman, James Ostell, Eric W. Sayers Jan 2010

Genbank, Dennis A. Benson, Ilene Karasch-Mizrachi, David J. Lipman, James Ostell, Eric W. Sayers

Harold W. Manter Laboratory of Parasitology: Library Materials

GenBank(R) is a comprehensive database that contains publicly available nucleotide sequences for more than 380,000 organisms named at the genus level or lower, obtained primarily through submissions from individual laboratories and batch submissions from large-scale sequencing projects, including whole genome shotgun (WGS) and environmental sampling projects. Most submissions are made using the web-based BankIt or standalone Sequin programs, and accession numbers are assigned by GenBank staff upon receipt. Daily data exchange with the European Nucleotide Archive (ENA) and the DNA Data Bank of Japan (DDBJ) ensures worldwide coverage. GenBank is accessible through the NCBI Entrez retrieval system that integrates data …


Evolutionary History Of Mammalian Sucking Lice (Phthiraptera: Anoplura), Jessica E. Light, Vincent S. Smith, Julie M. Allen, Lance A. Durden, David L. Reed Jan 2010

Evolutionary History Of Mammalian Sucking Lice (Phthiraptera: Anoplura), Jessica E. Light, Vincent S. Smith, Julie M. Allen, Lance A. Durden, David L. Reed

Harold W. Manter Laboratory of Parasitology: Library Materials

Background

Sucking lice (Phthiraptera: Anoplura) are obligate, permanent ectoparasites of eutherian mammals, parasitizing members of 12 of the 29 recognized mammalian orders and approximately 20% of all mammalian species. These host specific, blood-sucking insects are morphologically adapted for life on mammals: they are wingless, dorso-ventrally flattened, possess tibio-tarsal claws for clinging to host hair, and have piercing mouthparts for feeding. Although there are more than 540 described species of Anoplura and despite the potential economical and medical implications of sucking louse infestations, this study represents the first attempt to examine higher-level anopluran relationships using molecular data. In this study, we …


New Species In The Genus Monoecocesuts (Cestoda: Anoplocephalidae) From Neotropical Rodents (Caviidae And Sigmodontidae), Terry R. Haverkost, Scott Lyell Gardner Jan 2010

New Species In The Genus Monoecocesuts (Cestoda: Anoplocephalidae) From Neotropical Rodents (Caviidae And Sigmodontidae), Terry R. Haverkost, Scott Lyell Gardner

Scott L. Gardner Publications

Anoplocephalid cestodes have a worldwide distribution, but relatively few species are known from South American rodents. By examining the collections of the Harold W. Manter Laboratory of Parasitology and the United States National Parasite Collection, 6 new species of Monoecocestus Beddard, 1914, are described, along with a redescription of Monoecocestus mackiewiczi Schmidt and Martin, 1978, based on the type specimens. The discussion includes commentary about uterine development, an important taxonomic character of the family, the vaginal dilation in immature segments (a character of potential taxonomic importance), and the implication of host usage to the evolutionary history and biogeography of species …


Structural Restoration Of Nematodes And Acanthocephalans Fixed In High Percentage Alcohol Using Dess Solution And Rehydration, Soraya Naem, Christopher Pagan, Steven A. Nadler Jan 2010

Structural Restoration Of Nematodes And Acanthocephalans Fixed In High Percentage Alcohol Using Dess Solution And Rehydration, Soraya Naem, Christopher Pagan, Steven A. Nadler

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Ninety-five percent ethanol is the most widely used field and laboratory preservative for nematodes and other helminth specimens intended for use in molecular systematics. Preservation of nematodes in high-concentration alcohols results in structural dehydration artifacts, including shrinkage and body surface distortions sufficient to obscure features required for morphological identification and analysis, thereby compromising precise morphometrics. However, treating dehydrated nematodes using a solution of DMSO, disodium EDTA, and NaCl, followed by rehydration in water produces marked improvements in specimen shape and surface features, resulting from diffusion of water into the tissues and pseudocoelom as the internal salt concentration is reduced. Following …


Soil-Transmitted Helminthiases: Implications Of Climate Change And Human Behavior, Haylee J. Weaver, John M. Hawdon, Eric P. Hoberg Jan 2010

Soil-Transmitted Helminthiases: Implications Of Climate Change And Human Behavior, Haylee J. Weaver, John M. Hawdon, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Soil-transmitted helminthiases (STHs) collectively cause the highest global burden of parasitic disease after malaria and are most prevalent in the poorest communities, especially in sub-Saharan Africa. Climate change is predicted to alter the physical environment through cumulative impacts of warming and extreme fluctuations in temperature and precipitation, with cascading effects on human health and wellbeing, food security and socioeconomic infrastructure. Understanding how the spectrum of climate change effects will influence STHs is therefore of critical importance to the control of the global burden of human parasitic disease. Realistic progress in the global control of STH in a changing climate requires …


Muellerius Capillaris Dominates The Lungworm Community Of Bighorn Sheep At The National Bison Range, Montana, Vanessa O. Ezenwa, Alicia M. Hines, Elizabeth A. Archie, Eric P. Hoberg, Ingrid M. Asmundsson, John T. Hogg Jan 2010

Muellerius Capillaris Dominates The Lungworm Community Of Bighorn Sheep At The National Bison Range, Montana, Vanessa O. Ezenwa, Alicia M. Hines, Elizabeth A. Archie, Eric P. Hoberg, Ingrid M. Asmundsson, John T. Hogg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Lungworm infections are common among bighorn sheep (Ovis canadensis) in North America, and the predominant species reported are Protostrongylus stilesi and P. rushi. The only records of another lungworm species, Muellerius capillaris, infecting bighorns come from South Dakota, USA. At the National Bison Range (NBR), Montana, USA we found that across six sampling periods, 100% of wild bighorn sheep surveyed were passing first-stage dorsal-spined larvae (DSL) which appeared to be consistent with M. capillaris. By contrast, only 39%or fewer sheep were passing Protostrongylus larvae. Using molecular techniques, we positively identified the DSL from the NBR …


Examination Of Homalometron Elongatum Manter, 1947 And Description Of A New Congener From Eucinostomus Currani Zahuranec, 1980 In The Pacific Ocean Off Costa Rica, Jessica H. Parker, Stephen S. Curran, Robin M. Overstreet, Vasyl V. Tkach Jan 2010

Examination Of Homalometron Elongatum Manter, 1947 And Description Of A New Congener From Eucinostomus Currani Zahuranec, 1980 In The Pacific Ocean Off Costa Rica, Jessica H. Parker, Stephen S. Curran, Robin M. Overstreet, Vasyl V. Tkach

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Homalometron elongatum is reexamined using heat-killed material that was not subjected to pressure during fixation from Gerres cinereus collected from San Juan Harbor, Puerto Rico, U.S.A. The new material is compared with some paratype specimens and differs by having a much less variable forebody length, and a median rather than submedian genital pore. Tegumental spines reportedly cover the anterior end of the body but we observed tegumental spines covering the entire body surface in both the paratype and new material. Homalometron lesliorum n. sp. is described from Eucinostomus currani from the Pacific coasts of Costa Rica and Nicaragua. The new …


How Specialists Can Be Generalists: Resolving The "Parasite Paradox" And Implications For Emerging Infectious Disease, Salvatore J. Agosta, Niklas Janz, Daniel R. Brooks Jan 2010

How Specialists Can Be Generalists: Resolving The "Parasite Paradox" And Implications For Emerging Infectious Disease, Salvatore J. Agosta, Niklas Janz, Daniel R. Brooks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The parasite paradox arises from the dual observations that parasites (broadly construed, including phytophagous insects) are resource specialists with restricted host ranges, and yet shifts onto relatively unrelated hosts are common in the phylogenetic diversification of parasite lineages and directly observable in ecological time. We synthesize the emerging solution to this paradox: phenotypic flexibility and phylogenetic conservatism in traits related to resource use, grouped under the term ecological fitting, provide substantial opportunities for rapid host switching in changing environments, in the absence of the evolution of novel host-utilization capabilities. We discuss mechanisms behind ecological fitting, its implications for defining specialists …


First Report Of Viral Pathogens Wssv And Ihhnv In Argentine Crustaceans [Note], Sergio Roberto Martorelli, Robin M. Overstreet, Jean A. Jovanovich Alvillar Jan 2010

First Report Of Viral Pathogens Wssv And Ihhnv In Argentine Crustaceans [Note], Sergio Roberto Martorelli, Robin M. Overstreet, Jean A. Jovanovich Alvillar

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The pathogenic penaeid shrimp viruses white spot syndrome virus (WSSV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV) are reported for the first time from Argentina. They both occurred in wild crustaceans in Bahia Blanca Estuary, with WSSV detected by polymerase chain reaction (pCR) or real time quantitative pCR (qpCR) methods as infecting samples as high as 56% of the penaeid Artemesia longinaris Bate, 1888, 67% of the grapsoid Cyrtograpsus angulatus dana, 1851, and 40% of the introduced palaemonid Palaemon macrodactylus Rathbun, 1902. The highest detected copy number was 39,600 copies/μg dNA. IHHNV was tested for using pCR in …


Discovery Of New Ohbayashinema Spp. (Nematoda: Heligmosomoidea) In Ochotona Princeps And Ochotona Cansus (Lagomorpha: Ochotonidae) From Western North America And Central Asia, With Considerations Of Historical Biogeography, M.-C. Durrette-Desset, Kurt E. Galbreath, Eric P. Hoberg Jan 2010

Discovery Of New Ohbayashinema Spp. (Nematoda: Heligmosomoidea) In Ochotona Princeps And Ochotona Cansus (Lagomorpha: Ochotonidae) From Western North America And Central Asia, With Considerations Of Historical Biogeography, M.-C. Durrette-Desset, Kurt E. Galbreath, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three new species of Ohbayashinema (Nematoda, Heligmosomoidea) are described from localities in western North America and central Asia. Two of these species, Ohbayashinema nearctica n. sp. and Ohbayashinema aspeira n. sp., are parasitic in American pika, Ochotona princeps. Ohbayashinema nearctica is differentiated from the 5 known species of the genus parasitic in Ochotonidae from the Old World by very long spicules and an oblique axis of orientation for the ridges composing the synlophe. Ohbayashinema aspeira, described only from females, is similar to Oh. nearctica based on the number of cuticular ridges at the midbody. It is mainly differentiated …


The Interplay Between Host Cells And The Human Pathogen Trypanosoma Cruzi: Role Of Toll-Like Receptors, Lilian Lie Nohara Jan 2010

The Interplay Between Host Cells And The Human Pathogen Trypanosoma Cruzi: Role Of Toll-Like Receptors, Lilian Lie Nohara

Open Access Theses & Dissertations

The protozoan parasite Trypanosoma cruzi is the etiologic agent of Chagas disease, a neglected infectious disease that is becoming a world health concern. This obligate intracellular parasite employs a diversity of molecules and strategies to successfully invade a wide variety of mammalian cells and modulate host immune responses, which are essential features for completion of its life cycle in the host. The major plasma membrane antigens of T. cruzi infective trypomastigote forms are glycosylphosphatidylinositol (tGPI)-anchored mucin-like glycoproteins. Although previous studies demonstrated that the proinflammatory responses induced by tGPIs are mediated by Toll-like receptor (TLR) 2, the involvement of other TLRs …


Community Structure And Seasonal Dynamics Of Dactylogyrus Spp. (Monogenea) On The Fathead Minnow (Pimephales Promelas) From The Salt Valley Watershed, Lancaster County, Nebraska, Alaine Knipes, John J. Janovy Jr. Dec 2009

Community Structure And Seasonal Dynamics Of Dactylogyrus Spp. (Monogenea) On The Fathead Minnow (Pimephales Promelas) From The Salt Valley Watershed, Lancaster County, Nebraska, Alaine Knipes, John J. Janovy Jr.

John J. Janovy, Jr. Publications

The gill monogene communities of Pimephales promelas (fathead minnow) in three distinct sites on converging streams were investigated from 2004 to 2006 in three different seasons. Thirty collections of P. promelas were made in southeastern Nebraska along three converging tributaries: Elk Creek (40.88534°N, 96.83366°W), West Oak Creek (40.9082°N, 96.81432°W), and Oak Creek (40.91402°N, 96.770583°W), Lancaster County, Nebraska. In all, 103 P. promelas were collected from Elk Creek, 115 from West Oak Creek, and 78 from Oak Creek and examined for gill monogenes. Among the P. promelas collected, 93.5% were infected with up to three species of Dactylogyrus, including Dactylogyrus …


Synlophe Structure For Species Of Longistrongylus (Nematoda: Trichostrongyloidea), Abomasal Parasites Among Ungulates From Sub-Saharan Africa, With Comparisons To The Global Ostertagiine Fauna, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt Dec 2009

Synlophe Structure For Species Of Longistrongylus (Nematoda: Trichostrongyloidea), Abomasal Parasites Among Ungulates From Sub-Saharan Africa, With Comparisons To The Global Ostertagiine Fauna, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The synlophe, or system of longitudinal cuticular ridges characteristic of some trichostrongyloid nematodes, is examined in detail for 6 of 8 species in Longistrongylus (Ostertagiinae) that occur in ungulates across sub-Saharan Africa. Among the species of Longistrongylus examined, 5 are characterized by a tapering pattern laterally in the cervical zone (anterior to the esophageal-intestinal junction), which is largely consistent among multiple male and female specimens; in contrast, for Longistrongylus meyeri the lateral pattern is parallel. The synlophe is bilaterally symmetrical, with ridges extending from the base of the cephalic expansion to near the caudal extremity in males and females. Ridges …


Exploring T. Brucei Hexokinase Biology: Localization And Inhibition Studies, Todd Lyda Dec 2009

Exploring T. Brucei Hexokinase Biology: Localization And Inhibition Studies, Todd Lyda

All Dissertations

Trypanosoma brucei, the causative agent of the disease African sleeping sickness
in humans and nagana in animals, is a scourge of sub-Saharan Africa. There is a
desperate need for more efficacious therapies for the disease; here we describe research
validating T. brucei hexokinase 1 (TbHK1) as a drug therapeutic target for T. brucei
infection and the identification and characterization of novel inhibitors of the enzyme by
both low throughput and high throughput means. Additionally this thesis introduces
efforts at characterizing a second T. brucei hexokinase, focusing mostly on cell biology
and the determination of localization.
The small molecule quercetin (QCN) …


Where Are The Parasites? [Letters], Susan J. Kutz, Andy P. Dobson, Eric P. Hoberg Nov 2009

Where Are The Parasites? [Letters], Susan J. Kutz, Andy P. Dobson, Eric P. Hoberg

Harold W. Manter Laboratory of Parasitology: Faculty Publications

First paragraph:

The review by E. Post et al. ("Ecological dynamics across the Arctic associated with recent climate change," 11 September 2009, p. 1,355) paid little heed to parasites and other pathogens. The rapidly growing literature on parasites in arctic and subarctic ecosystems provides empirical and observational evidence that climate-linked changes have already occurred. The life cycle of the protostrongylid lungworm of muskoxen, Umingmakstrongylus pallikuukensis, has changed, and the range of that organism and the winter tick, Dermacentor albipictus, has expanded.


Comparative Life Cycles And Life Histories Of North American Rhabdias Spp. (Nematoda: Rhabdiasidae): Lungworms From Snakes And Anurans, Gabriel J. Langford, John J. Janovy Jr. Oct 2009

Comparative Life Cycles And Life Histories Of North American Rhabdias Spp. (Nematoda: Rhabdiasidae): Lungworms From Snakes And Anurans, Gabriel J. Langford, John J. Janovy Jr.

John J. Janovy, Jr. Publications

The present study used experimental infections to compare the life cycles and life histories of 6 Rhabdias spp. infecting snakes and anurans. Free-living development of anuran lungworms was primarily limited to heterogonic reproduction, and females utilized matricidal endotoky exclusively, whereas snake lungworms primarily reproduced homogonically and, when heterogonic reproduction occurred, females used a combination of releasing eggs and matricidal endotoky. Infective snake lungworms survived for longer periods in fresh water compared to anuran worms. Infective anuran lungworms penetrated into the skin of frogs and toads; few infections resulted from per os infections. In contrast, snake lungworms were unable to penetrate …


Eimeria Spp. (Apicomplexa: Eimeriidae) From The Plateau Pika, Ochotona Curzoniae, From Haibei Area, Qinghai Province, China, With The Description Of Two New Species, Yi-Fan Cao, Run-Roung Ye, Jian-Hua Wu, Jiang-Hui Bian, Donald W. Duszynski Oct 2009

Eimeria Spp. (Apicomplexa: Eimeriidae) From The Plateau Pika, Ochotona Curzoniae, From Haibei Area, Qinghai Province, China, With The Description Of Two New Species, Yi-Fan Cao, Run-Roung Ye, Jian-Hua Wu, Jiang-Hui Bian, Donald W. Duszynski

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Fifty-two fecal samples from the Plateau pika, Ochotona curzoniae, collected in the Haibei Area, Qinghai Province, China, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five distinct morphotypes, all Eimeria species, were distinguished based on the structure of their sporulated oocysts. Three of these included Eimeria banffensis, Eimeria calentinei, and Eimeria cryptobarretti, all of which have been described previously from other Ochotona species. We also studied 2 morphotypes that we feel have sufficient qualitative and quantitative characters to distinguish them from all previously described species; herein, we identify them as putative new species. Eimeria qinghaiensis …


Sheep Updates 2009, Brown Besier, L. J. E. Karlsson, J. C. Greeff, A. C. Schlink, Mark Ferguson, Greg Lee, Sue Hatcher, Bruce Michael, Rob Woodgate, Darren Michael, Mandy Curnow, Julia Smith, John Young, Andrew Thompson, Chris Oldham Jul 2009

Sheep Updates 2009, Brown Besier, L. J. E. Karlsson, J. C. Greeff, A. C. Schlink, Mark Ferguson, Greg Lee, Sue Hatcher, Bruce Michael, Rob Woodgate, Darren Michael, Mandy Curnow, Julia Smith, John Young, Andrew Thompson, Chris Oldham

Sheep Updates

This session covers seven papers from different authors:

1. Scouring Management and Worm Control, Brown Besier, Department of Agriculture and Food, Western Australia

2.Breeding sheep for resistance to breech strike:- Selection results in WA, LJE Karlsson, JC Greeff & AC Schlink, Department of Agriculture and Food, Western Australia

3.Future Ewe - matching genetics to the production system, Mark Ferguson, Department of Agriculture and Food, Western Australia

4. Within-flock selection of ewes: opportunities for gains in reproduction, Greg Leeand Sue Hatcher, NSW Department of Primary Industries & Australian CRCforSheep Industry Innovation (Orange)

5. Managing Merinos …


American Society Of Parasitologists Newsletter, V. 31, No. 2, Summer 2009, Scott Lyell Gardner Jul 2009

American Society Of Parasitologists Newsletter, V. 31, No. 2, Summer 2009, Scott Lyell Gardner

American Society of Parasitologists: Newsletter

An issue of the American Society of Parasitologists' quarterly newsletter, also called the Journal of Parasitology Newsletter.


Lipid Targets Of The Antimalarial Trioxanes In Plasmodium Falciparum, Carmony Leah Hartwig Jul 2009

Lipid Targets Of The Antimalarial Trioxanes In Plasmodium Falciparum, Carmony Leah Hartwig

Biological Sciences Theses & Dissertations

Malaria is among the most debilitating diseases of man. The protozoan parasite, Plasmodium falciparum, causes over a million annual fatalities. The antimalarial trioxanes, exemplified by artemisinin, are among the few pharmaceuticals for which clinical resistance has not become widespread. Artemisinin is a naturally occurring sesquiterpene lactone, containing a unique endoperoxide pharmacophore. Despite extensive study, the precise antimalarial mechanism of action of trioxanes remains elusive. Heme iron-mediated cleavage of the endoperoxide within the parasite digestive vacuole is hypothesized to generate cytotoxic metabolites capable of alkylating heme and damaging cellular macromolecules. The hypothesis of this research is that the endoperoxide pharmacophore …


Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

Biology Faculty Publications

Studies on life cycles and epizootiology of North American frog bladder flukes indicate that adult frogs become infected predominantly by ingesting tadpoles or other frogs that serve as second intermediate hosts for gorgoderid metacercariae. Other studies have indicated that newly metamorphosed frogs are rarely infected with these parasites because they are gape-limited predators that cannot feed on large intermediate hosts such as tadpoles and other frogs. We examined the role of potential intermediate hosts in the recruitment of the frog bladder fluke, Gorgoderina attenuata, to metamorphosed northern leopard frogs, Woodhouse’s toads, and bullfrogs from western Nebraska. We completed the …


Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

Biology Faculty Publications

Morphological characters used to differentiate North American bladder flukes, Gorgoderina spp., are problematic and different authors use different morphological characteristics for distinguishing species. More importantly, no type specimens exist for four of the 12 North American species infecting anuran and caudatan hosts. A redescription of Gorgoderina attenuata (Stafford, 1902) Stafford, 1905 is based on new collections from 6 species of anurans from Arkansas, Nebraska, New York, and Wisconsin. Morphological comparisons between gravid G. attenuata recovered from bullfrogs and northern leopard frogs indicated statistically significant differences in 11 of 28 morphological characters examined. However, there was overlap among all of these …


Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

John J. Janovy, Jr. Publications

Morphological characters used to differentiate North American bladder flukes, Gorgoderina spp., are problematic and different authors use different morphological characteristics for distinguishing species. More importantly, no type specimens exist for four of the 12 North American species infecting anuran and caudatan hosts. A redescription of Gorgoderina attenuata (Stafford, 1902) Stafford, 1905 is based on new collections from 6 species of anurans from Arkansas, Nebraska, New York, and Wisconsin. Morphological comparisons between gravid G. attenuata recovered from bullfrogs and northern leopard frogs indicated statistically significant differences in 11 of 28 morphological characters examined. However, there was overlap among all of these …


Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr. Jun 2009

Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.

John J. Janovy, Jr. Publications

Studies on life cycles and epizootiology of North American frog bladder flukes indicate that adult frogs become infected predominantly by ingesting tadpoles or other frogs that serve as second intermediate hosts for gorgoderid metacercariae. Other studies have indicated that newly metamorphosed frogs are rarely infected with these parasites because they are gape-limited predators that cannot feed on large intermediate hosts such as tadpoles and other frogs. We examined the role of potential intermediate hosts in the recruitment of the frog bladder fluke, Gorgoderina attenuata, to metamorphosed northern leopard frogs, Woodhouse’s toads, and bullfrogs from western Nebraska. We completed the …


Robustostrongylus Aferensis Gen. Nov. Et Sp. Nov. (Nematoda: Trichostrongyloidea) In Kob (Kobus Kob) And Hartebeest (Alcelaphus Buselaphus Jacksoni) (Artiodactyla) From Sub-Saharan Africa, With Further Ruminations On The Ostertagiinae, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt Jun 2009

Robustostrongylus Aferensis Gen. Nov. Et Sp. Nov. (Nematoda: Trichostrongyloidea) In Kob (Kobus Kob) And Hartebeest (Alcelaphus Buselaphus Jacksoni) (Artiodactyla) From Sub-Saharan Africa, With Further Ruminations On The Ostertagiinae, Eric P. Hoberg, Arthur Abrams, Patricia A. Pilitt

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Abomasal nematodes (Ostertagiinae: Trichostrongyloidea), representing a previously unrecognized genus and species, were discovered in kob (Kobus kob) and kongoni (hartebeest) (Alcelaphus buselaphus jacksoni) from Uganda during surveys of ungulate parasites in the 1960s. Robustostrongylus aferensis gen. nov. et sp. nov. is characterized by a ventriculus-like, bilobed valve at the junction of the esophagus and intestine, a synlophe with unusually robust ridges, cervical papillae and excretory pore situated posterior to the mid-length of the esophagus, a unique body form and large diameter in males and females, a relatively anterior position for the vulva, and strongly convoluted and …


Daggerblade Grass Shrimp (Palaemonetes Pugio): A Reservoir Host For Yellow-Head Virus (Yhv), Hongwei Ma, Robin M. Overstreet, Jean A. Jovonovich Jun 2009

Daggerblade Grass Shrimp (Palaemonetes Pugio): A Reservoir Host For Yellow-Head Virus (Yhv), Hongwei Ma, Robin M. Overstreet, Jean A. Jovonovich

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Yellow-head virus (YHV) is a major pathogen in penaeid shrimps. We surveyed 13 crustacean species in eight families from two orders that are commonly found in the Mississippi coastal area and freshwater environments as potential reservoir or carrier hosts of YHV. Using semi-nested polymerase chain reaction (PCR) on relatively small sample sizes, we did not detect any natural infection. However, when the daggerblade grass shrimp, Palaemonetes pugio, and the blue crab, Callinectes sapidus, were exposed to YHV by injection and per os, YHV was detected in the tissue of P. pugio and in the hemolymph of C. sapidus …