Trichinella: Becoming a parasite.

Phylogenetic evidence indicates that free-living nematodes gave rise to parasitic nematodes where parasitism evolved independently at least 15 times. The high level of genetic and biological diversity among parasites dictates an equally high level of diversity in the transition to parasitism. We previously hypothesized that horizontal gene transfer (HGT) played an important role in the evolution of parasitism among early ancestors of Trichinella, mediated by an interplay of ecological and evolutionary pathways that contributed to persistence and diversification.

*Inactivation of encysted muscle larvae of Trichinella spiralis in pigs using Mebendazole.

We evaluated the effect of 4 anthelmintic treatments on the viability of Trichinella spiralis encysted muscle larvae (ML) 55 days post infection (PI) in experimentally infected pigs. Muscle larvae were isolated from pig muscle by artificial digestion after oral treatment of pigs with Levamisole (8 mg/kg, daily for 5 days) and Mebendazole (50 mg/kg, daily for 5 days); Doramectin (0.3 mg/kg, single IM injection), and Moxidectin (0.

Gastrointestinal parasites of a reintroduced semi-wild plains bison () herd: Examining effects of demographic variation, deworming treatments, and management strategy.

Bison ( spp) are being reintroduced into semi-wild, spatially constrained herds across North America and Europe. Herd managers are concerned about gastrointestinal (GI) nematode parasites as they care for the health of their bison. We examine how demographics, grazing location, herd management, and anthelmintic treatments affect the fecal egg counts (FECs) of GI nematodes within a reintroduced Plains bison () herd in the Great Plains.

Wild ruminants as reservoirs of domestic livestock gastrointestinal nematodes.

Gastrointestinal nematode (GIN) infections in cattle cause appetite suppression which leads to poor feed conversion, reduced weight gain and reduced milk production. Overuse and exclusive reliance on anthelmintic drugs has resulted in widespread resistance in many parasitic nematode species infecting livestock making control increasingly difficult. Wild ruminants are competent hosts of a number of nematode species that typically infect and are best adapted for cattle, sheep, and goats.

Analysis of the Trichuris suis excretory/secretory proteins as a function of life cycle stage and their immunomodulatory properties.

Parasitic worms have a remarkable ability to modulate host immune responses through several mechanisms including excreted/secreted proteins (ESP), yet the exact nature of these proteins and their targets often remains elusive. Here, we performed mass spectrometry analyses of ESP (TsESP) from larval and adult stages of the pig whipworm Trichuris suis (Ts) and identified ~350 proteins. Transcriptomic analyses revealed large subsets of differentially expressed genes in the various life cycle stages of the parasite.

Cholesterol of lipid rafts is a key determinant for entry and post-entry control of porcine rotavirus infection.

Background: Lipid rafts are major structural components in plasma membranes that play critical roles in many biological processes including virus infection. However, few reports have described the relationship between lipid rafts and porcine rotavirus (PRV) infection. In this study, we investigated whether or not the locally high concentrations (3-5 fold) of cholesterol present in lipid rafts are required for PRV infection, and further examined which stages of the infection process are most affected.

Long-read sequencing improves assembly of Trichinella genomes 10-fold, revealing substantial synteny between lineages diverged over 7 million years.

Genome assemblies can form the basis of comparative analyses fostering insight into the evolutionary genetics of a parasite's pathogenicity, host-pathogen interactions, environmental constraints and invasion biology; however, the length and complexity of many parasite genomes has hampered the development of well-resolved assemblies. In order to improve Trichinella genome assemblies, the genome of the sylvatic encapsulated species Trichinella murrelli was sequenced using third-generation, long-read technology and, using syntenic comparisons, scaffolded to a reference genome assembly of Trichinella spiralis, markedly improving both. A high-quality draft assembly for T.

Trichinella Nativa Outbreak With Rare Thrombotic Complications Associated With Meat From a Black Bear Hunted in Northern Ontario.

Background: Although trichinellosis is known to cause thrombotic disease, serious thrombotic events are rare and have not been previously associated with Trichinella nativa infection.

Methods: Patient interviews and medical chart reviews were conducted on 10 men who became ill following consumption of a common source of black bear meat. Trichinella serology on patient sera as well as polymerase chain reaction (PCR) and larval identification of the meat samples was conducted.

Hybridization is limited between two lineages of freeze-resistant Trichinella during coinfection in a mouse model.

Hybridization between two closely related but distinct genetic lineages may lead to homogenization of the two lineages with potentially novel phenotypes, or selective pressure to avoid hybridization if the two lineages are truly distinct. Trichinella nativa and Trichinella T6 are zoonotic nematode parasites which can be distinguished genetically despite occasional hybridization. Here, using an experimental murine model, we attempt to determine whether there are barriers to hybridization when sizeable numbers of each lineage are allowed to coinfect a host.

Effectiveness of current anthelmintic treatment programs on reducing fecal egg counts in United States cow-calf operations.

During the United States Department of Agriculture (USDA) National Animal Health Monitoring System's (NAHMS) 2007-2008 beef study, producers from 24 states were offered the opportunity to evaluate their animals for internal parasites and for overall responses to treatment with anthelmintics. A lapse of 45 d was required between initial sampling and any previous treatments. Choice of anthelmintic (oral benzimidazoles, and both injectable and pour-on endectocides) was at the discretion of the producer so as not to alter the local control programs.

Prevalence of internal parasites in beef cows in the United States: Results of the National Animal Health Monitoring System's (NAHMS) beef study, 2007-2008.

During the United States Department of Agriculture (USDA) National Animal Health Monitoring System's (NAHMS) 2007-2008 beef study, 567 producers from 24 US States were offered the opportunity to collect fecal samples from weaned beef calves and have them evaluated for the presence of parasite eggs (Phase 1). Participating producers were provided with instructions and materials for sample collection. Up to 20 fresh fecal samples were collected from each of the 99 participating operations.

Putative phage-display epitopes of the porcine epidemic diarrhea virus S1 protein and their anti-viral activity.

Porcine epidemic diarrhea virus (PEDV) is a pathogen of swine that causes severe diarrhea and dehydration resulting in substantial morbidity and mortality in newborn piglets. Phage display is a technique with wide application, in particular, the identification of key antigen epitopes for the development of therapeutic and diagnostic reagents and vaccines. To identify antigen epitopes with specificity for PEDV, a monoclonal antibody (MAb-5E12) against the immunodominant region of the PEDV Spike protein (S1) was used as the target for biopanning a 12-mer phage display, random peptide library.

Anthropogenics: human influence on global and genetic homogenization of parasite populations.

The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This includes the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been challenging. In-depth comparisons among parasite populations extending to landscape-level processes affecting disease emergence have remained elusive.

An overview of live attenuated recombinant pseudorabies viruses for use as novel vaccines.

Pseudorabies virus (PRV) is a double-stranded, DNA-based swine virus with a genome approximating 150 kb in size. PRV has many nonessential genes which can be replaced with genes encoding heterologous antigens but without deleterious effects on virus propagation. Recombinant PRVs expressing both native and foreign antigens are able to stimulate immune responses.

A phage-displayed peptide recognizing porcine aminopeptidase N is a potent small molecule inhibitor of PEDV entry.

Three phage-displayed peptides designated H, S and F that recognize porcine aminopeptidase N (pAPN), the cellular receptor of porcine transmissible gastroenteritis virus (TGEV) were able to inhibit cell infection by TGEV. These same peptides had no inhibitory effects on infection of Vero cells by porcine epidemic diarrhea virus (PEDV). However, when PEDV, TGEV and porcine pseudorabies virus were incubated with peptide H (HVTTTFAPPPPR), only infection of Vero cells by PEDV was inhibited.

Antiviral effect of diammonium glycyrrhizinate on cell infection by porcine parvovirus.

Porcine parvovirus (PPV) can cause reproductive failure in swine, resulting in economic losses to the industry. Antiviral effects of diammonium glycyrrhizinate (DG) have been reported on several animal viruses; however, to date it has yet to be tested on PPV. In this study, the antiviral activity of DG on swine testis (ST) cell infection by PPV was investigated using an empirically determined, non-toxic concentration of DG and three different experimental designs: (1) pre-treatment of virus prior to infection; (2) pre-treatment of cells prior to infection; and (3) direct treatment of virus-infected cells.

Transmissible gastroenteritis virus: identification of M protein-binding peptide ligands with antiviral and diagnostic potential.

The membrane (M) protein is one of the major structural proteins of coronavirus particles. In this study, the M protein of transmissible gastroenteritis virus (TGEV) was used to biopan a 12-mer phage display random peptide library. Three phages expressing TGEV-M-binding peptides were identified and characterized in more depth.

New pieces of the Trichinella puzzle.

Contrary to our understanding of just a few decades ago, the genus Trichinella now consists of a complex assemblage of no less than nine different species and three additional genotypes whose taxonomic status remains in flux. New data and methodologies have allowed advancements in detection and differentiation at the population level which in turn have demonstrably advanced epidemiological, immunological and genetic investigations. In like manner, molecular and genetic studies have permitted us to hypothesise biohistorical events leading to the worldwide dissemination of this genus, and to begin crystalising the evolution of Trichinella on a macro scale.

Evolution and homologous recombination of the hemagglutinin-esterase gene sequences from porcine torovirus.

The objective of the present study was to gain new insights into the evolution, homologous recombination, and selection pressures imposed on the porcine torovirus (PToV), by examining the changes in the hemagglutinin-esterase (HE) gene. The most recent common ancestor of PToV was estimated to have emerged 62 years ago based upon HE gene sequence data obtained from PToV isolates originating from Spain, South Korea, Netherlands, Hungary, and Italy and using the HE gene of Bovine torovirus isolates Niigata1 (AB661456) and Niigata3 (AB661458) as outgroups. The HE gene sequence data segregated all the PToV isolates into two well-supported monophyletic groups; however, various isolates from Spain, Italy, and South Korea did not segregate geographically suggesting very recent translocation of the viruses to these localities.

Transcriptome analyses reveal protein and domain families that delineate stage-related development in the economically important parasitic nematodes, Ostertagia ostertagi and Cooperia oncophora.

Background: Cooperia oncophora and Ostertagia ostertagi are among the most important gastrointestinal nematodes of cattle worldwide. The economic losses caused by these parasites are on the order of hundreds of millions of dollars per year. Conventional treatment of these parasites is through anthelmintic drugs; however, as resistance to anthelmintics increases, overall effectiveness has begun decreasing.

Incidence rates and deaths of tuberculosis in HIV-negative patients in the United States and Germany as analyzed by new predictive model for infection.

Incidence and mortality due to tuberculosis (TB) have been decreasing worldwide. Given that TB is a cosmopolitan disease, proper surveillance and evaluation are critical for controlling dissemination. Herein, mathematical modeling was performed in order to: 1) demonstrate a correlation between the incidence of TB in HIV-free patients in the US and Germany, and their corresponding mortality rates; 2) show the utility of the newly developed D-R algorithm for analyzing and predicting the incidence of TB in both countries; and 3) inform us on population death rates due to TB in HIV-negative patients.

Discernible but limited introgression has occurred where Trichinella nativa and the T6 genotype occur in sympatry.

The genetic diversity within and among parasite populations provides clues to their evolutionary history. Here, we sought to determine whether mitochondrial and microsatellite DNA variation could be used to evaluate the extent of differentiation, gene flow and historical reproductive isolation among the freeze resistant parasites Trichinella nativa and the Trichinella T6 genotype infecting wolverines (Gulo gulo) in Nunavut, Canada. To this end, we genotyped Trichinella isolates derived from the diaphragms of 39 wolverines from this locale to reference strains of T.

Use of the D-R model to define trends in the emergence of Ceftazidime-resistant Escherichia coli in China.

Objective: To assess the efficacy of the D-R model for defining trends in the appearance of Ceftazidime-resistant Escherichia coli.

Methods: Actual data related to the manifestation of Ceftazidime-resistant E. coli spanning years 1996-2009 were collected from the China National Knowledge Internet.

The draft genome of the parasitic nematode Trichinella spiralis.

Genome evolution studies for the phylum Nematoda have been limited by focusing on comparisons involving Caenorhabditis elegans. We report a draft genome sequence of Trichinella spiralis, a food-borne zoonotic parasite, which is the most common cause of human trichinellosis. This parasitic nematode is an extant member of a clade that diverged early in the evolution of the phylum, enabling identification of archetypical genes and molecular signatures exclusive to nematodes.