Ostertagia ostertagi Mediates Early Host Immune Responses via Macrophage and Toll-Like Receptor Pathways.

Ostertagia ostertagi is an abomasal parasite with significant economic impact on the cattle industry. Early host immune responses are poorly understood. Here, we examined time course expression of Toll-like receptors (TLRs) in peripheral blood mononuclear cells (PBMC) during infection where PBMC macrophages (Mϕ) generated both pro- and anti-inflammatory responses when incubated with excretory/secretory products (ESP) from fourth-stage larvae (OoESP-L4) or adult worms (OoESP-Ad). First, changes in cell morphology clearly showed that both OoESP-L4 and OoESP-Ad activated PBMC-Mϕ in vitro, resulting in suppressed CD40 and increased CD80 expression. Expression of mRNAs for TLR1, -4, -5, and -7 peaked 7 days postinfection (dpi) (early L4), decreased by 19 dpi (postemergent L4 and adults) and then increased at 27 dpi (late adults). The proinflammatory cytokine tumor necrosis factor alpha (TNF-α) (transcript and protein) increased in the presence of OoESP-Ad, and the anti-inflammatory cytokine interleukin 10 (IL-10) (protein) decreased in the presence of OoESP-L4 or OoESP-Ad; however, IL-10 mRNA was upregulated, and IL-6 (protein) was downregulated by OoESP-L4. When PBMC-Mϕ were treated with ligands for TLR4 or TLR5 in combination with OoESP-Ad, the transcripts for TNF-α, IL-1, IL-6, and IL-10 were significantly downregulated relative to treatment with TLR4 and TLR5 ligands only. However, the effects of TLR2 ligand and OoESP-Ad were additive, but only at the lower concentration. We propose that O. ostertagi L4 and adult worms utilize competing strategies via TLRs and Mϕ to confuse the immune system, which allows the worm to evade the host innate responses.

A simple molecular method to identify and quantify genera of gastrointestinal nematodes of cattle.

Classic approaches for antemortem identification of gastrointestinal nematodes (GIN) require coproculture of eggs and morphological examination. While adequate for diagnosis, many PCR techniques cannot easily quantify mixed infections without controls and/or standard curves. Herein, we developed a simple and rapid test for differentiating and quantifying mixed infections of GIN using PCR products separated by capillary electrophoresis. Among the cattle GIN, the ITS2 region is sufficiently distinct in length to delineate among the most common infecting genera, Ostertagia ostertagi = 373 bases (b), Haemonchus contortus (placei) = 366b, Cooperia punctata (oncophora) = 376b, Trichostrongylus axei = 372b, and Oesophagostomum radiatum = 357b. Conserved primers were synthesized that span the ITS2 where one primer was fluorescently labeled with 6-FAM. DNAs from infective L3 were PCR amplified then loaded onto an ABI 3130 sequencer adapted for size fragment analysis. Resulting peak amplitudes were both diagnostic and quantitative on a relative basis. As proof of principle, quantification was performed on PCR fragments from mixed species pairs of Ostertagia ostertagi, Cooperia punctata, and Haemonchus contortus and analyzed using Gene Marker V1.85 software. In all cases, linear responses were observed where R2 > 0.97 and line slopes ranged between 0.90 and 1.1. When tested on eggs from naturally infected animals, the assay showed superior results on two farms when compared to coproculture and morphological identification. Using wildlife-derived samples, results coincided well with deep amplicon sequencing. The assay is adaptable to large-scale studies, does not require comparative PCR controls, and should be compliant with GIN from small ruminant livestock.

Initial analysis of copy number variations in cattle selected for resistance or susceptibility to intestinal nematodes.

Genomic structural variation is an important and abundant source of genetic and phenotypic variation. We report an initial analysis of copy number variations (CNVs) in cattle selected for resistance or susceptibility to intestinal nematodes. We performed three array comparative genomic hybridization (CGH) experiments to compare Angus cattle with extreme phenotypes for fecal egg count and serum pepsinogen level. We identified 20 CNVs in total, of which 12 were within known chromosomes harboring or adjacent to gains or losses. About 85% of the CNV identified (17/20) overlapped with cattle CNV regions that were reported recently. Selected CNVs were further validated by independent methods using quantitative PCR (qPCR) and FISH. Pathway analyses indicated that annotated cattle genes within these variable regions are particularly enriched for immune function affecting receptor activities, signal transduction, and transcription. Analysis of transcription factor binding sites (TFBS) within the promoter regions of differentially expressed genes suggested that common transcription factors are probably involved in parasite resistance. These results provide valuable hypotheses for the future study of cattle CNVs underlying economically important health and production traits.

Recovery of cognitive function after traumatic brain injury: a multilevel modeling analysis of Canadian outcomes.

OBJECTIVE: To ascertain patterns of cognitive recovery during the first year after traumatic brain injury (TBI). Specifically, differential recovery across cognitive domains was investigated. DESIGN: Prospective, longitudinal, naturalistic, 1-year follow-up study. SETTING: Large, urban inpatient neurorehabilitation program. PARTICIPANTS: Patients (N=75) with moderate to severe TBI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Patients with TBI were followed over the course of 1 year, during which participants' neuropsychological status was repeatedly evaluated at 3 time points (2, 5, and 12 months postinjury). RESULTS: Multilevel modeling results were consistent with previous research, demonstrating that recovery in the first year postinjury is asymptotic in nature, with more accelerated recovery occurring during the first 5 to 6 months. Importantly, results also suggest that recovery is not uniform across cognitive domains. From 2 to 5 months postinjury, steeper recovery curves were revealed for indices of memory, speeded executive function, verbal abstraction, and manual dexterity relative to untimed tests of executive function and word knowledge. Recovery trajectories did not significantly vary as a function of cognitive domain over the course of the last 5 to 12 months. CONCLUSIONS: These results are the first to explore trajectories of recovery directly as a function of multiple cognitive domains. They are expected to have implications for rehabilitative efforts as well as our understanding of the architecture of natural recovery after TBI.

Prediction of return to productivity after severe traumatic brain injury: investigations of optimal neuropsychological tests and timing of assessment.

OBJECTIVES: (1) To examine predictive validity of global neuropsychological performance, and performance on timed tests (controlling for manual motor function) and untimed tests, including attention, memory, executive function, on return to productivity at 1 year after traumatic brain injury (TBI). (2) To compare predictive validity at 8 weeks versus 5 months postinjury. (3) To examine predictive validity of early degree of recovery (8wk-5mo postinjury) for return to productivity. DESIGN: Longitudinal, within subjects. SETTING: Inpatient neurorehabilitation and community. PARTICIPANTS: Patients (N=63) with moderate to severe TBI. INTERVENTIONS: Not applicable. PRIMARY OUTCOME: return to productivity at 1 year postinjury. Primary predictors: neuropsychological composite scores. Control variables: posttraumatic amnesia, acute care length of stay (LOS), Glasgow Coma Scale score, age, and estimated premorbid intelligence quotient. RESULTS: Return to productivity was significantly correlated with global neuropsychological performance at 5 months postinjury (P<.05) and showed a trend toward significance at 8 weeks. Performance on the untimed composite score, and more specifically executive and memory functions, mirrored this pattern. Logical Memory performance significantly predicted return to productivity, but not other memory tests. Timed tests showed no significance or trend at either time point. Early degree of recovery did not predict return to productivity. Among control variables, only acute care LOS was predictive of return to productivity. CONCLUSIONS: Findings validate utility of early neuropsychological assessment for predicting later return to productivity. They also provide more precise information regarding the optimal timing and test type: results support testing at 5 months postinjury on untimed tests (memory and executive function), but not simple attention or speed of mental processing. Findings are discussed with reference to previous literature.

Impact of wheeled seated mobility devices on adult users' and their caregivers' occupational performance: a critical literature review.

The prescription of wheeled seated mobility devices for clients with mobility impairment is a growing area in occupational therapy practice. The goal is to enhance client participation in occupation through technical intervention. This critical review examines the body of knowledge concerning the impact and effectiveness of the provision of wheeled seated mobility on the occupational performance of wheelchair users and their caregivers. The scope and gaps in the literature are defined to identify areas for future research. While the focus is on the methodological issues of the research reports, the relevance of findings to occupational therapy practice will also be reviewed. The results of the 46 studies in this review indicate that the majority of research conducted thus far have methodological limitations, which limits the extent to which this body of research can be drawn upon to provide evidence for the effectiveness of wheeled mobility systems. While most of the studies reviewed addressed constructs of relevance to occupational therapy practice, there was an emphasis on performance components and inadequate attention to engagement in occupations. This review is an important first step in building the ability of occupational therapists to demonstrate effectiveness in wheeled seating interventions.