Parasites of the invasive tilapia Oreochromis mossambicus: evidence for co-introduction

Reduced parasite species diversity and infection intensity on invasive populations can facilitate establishment and spread of invasive species. We investigated the parasite diversity of invasive populations of tilapia Oreochromis mossambicus from published literature and necropsies conducted on 72 fish captured in the Ross River, north Queensland, Australia. The parasite diversity of invasive O. mossambicus from 13 countries was compared to published reports on endemic populations in African river systems and tributaries to determine parasite species that had likely been co-introduced. In total, four parasite species were shared between native and invasive tilapia. We propose that these parasites (three monogeneans, Cichlidogyrus tilapiae Paperna, 1960, Cichlidogyrus sclerosus Paperna and Thurston, 1969, Cichlidogyrus halli (Price and Kirk, 1967) and one trichodinid Trichodina heterodentata Duncan, 1977) have likely been co-introduced with invasive Oreochromis mossambicus populations. Invasive Australian O. mossambicus had substantially reduced parasite diversity (five species) compared to cumulative parasite species diversity documented from the native region (23 species). Australian O. mossambicus were infected by two co-introduced parasites and three additional parasite species that have not been recorded previously on this species in Africa indicating possible parasite "spillback" from Australian natives or alternatively, acquisition from other introduced fauna. The substantially reduced parasite diversity on invasive Australian O. mossambicus could contribute to the ability of this species to become a serious fish pest

Determination of an Interaction Network between an Extracellular Bacterial Pathogen and the Human Host

A major gap in understanding infectious diseases is the lack of information about molecular interaction networks between pathogens and the human host. Haemophilus ducreyi causes the genital ulcer disease chancroid in adults and is a leading cause of cutaneous ulcers in children in the tropics. We developed a model in which human volunteers are infected on the upper arm with H. ducreyi until they develop pustules. To define the H. ducreyi and human interactome, we determined bacterial and host transcriptomic and host metabolomic changes in pustules. We found that in vivo H. ducreyi transcripts were distinct from those in the inocula, as were host transcripts in pustule and wounded control sites. Many of the upregulated H. ducreyi genes were found to be involved in ascorbic acid and anaerobic metabolism and inorganic ion/nutrient transport. The top 20 significantly expressed human pathways showed that all were involved in immune responses. We generated a bipartite network for interactions between host and bacterial gene transcription; multiple positively correlated networks contained H. ducreyi genes involved in anaerobic metabolism and host genes involved with the immune response. Metabolomic studies showed that pustule and wounded samples had different metabolite compositions; the top ion pathway involved ascorbate and aldarate metabolism, which correlated with the H. ducreyi transcriptional response and upregulation of host genes involved in ascorbic acid recycling. These data show that an interactome exists between H. ducreyi and the human host and suggest that H. ducreyi exploits the metabolic niche created by the host immune response.IMPORTANCE Dual RNA sequencing (RNA-seq) offers the promise of determining an interactome at a transcriptional level between a bacterium and the host but has yet to be done on any bacterial infection in human tissue. We performed dual RNA-seq and metabolomics analyses on wounded and infected sites following experimental infection of the arm with H. ducreyi Our results suggest that H. ducreyi survives in an abscess by utilizing l-ascorbate as an alternative carbon source, possibly taking advantage of host ascorbic acid recycling, and that H. ducreyi also adapts by upregulating genes involved in anaerobic metabolism and inorganic ion and nutrient transport. To our knowledge, this is the first description of an interaction network between a bacterium and the human host at a site of infection

Improved estimates of digestion correction factors and passage rates for harbor seal (Phoca vitulina) prey in the northeast Atlantic

Diet composition in pinnipeds is widely estimated using hard prey remains recovered from feces. To estimate the size and number of prey represented in fecal samples accurately, digestion correction factors (DCFs) must be applied to measurements and counts of fish otoliths and cephalopod beaks. In this study, 101 whole prey feeding trials were conducted with six harbor seals (Phoca vitulina) and 18 prey species. We derived species- and grade-specific estimates of digestion coefficients (DCs) and species-specific recovery rates (RRs) to account for partial and complete digestion, respectively. Greater than 98% of otoliths were passed within three days of consumption. RRs were smallest for Atlantic salmon smolts (RR = 0.306, SE = 0.031) and increasingly larger for sandeels (RR = 0.494, SE = 0.017), flatfish (RR = 0.789, SE = 0.033), and large gadoids (RR = 0.944, SE = 0.034). Species-specific otolith width DCs were smallest for Trisopterus species (DC = 1.14, SE = 0.015) and increasingly larger for flatfish (DC = 1.27, SE = 0.045), large gadoids (DC = 1.32, SE = 0.067) and sandeels (DC = 1.57, SE = 0.035). RRs were similar to those from gray seals (Halichoerus grypus), but harbor seal species- and grade-specific DCs were generally smaller. Differences in partial and complete digestion rates among prey species and between seal species highlight the importance of applying DCFs when reconstructing diet.PostprintPeer reviewe

Quantitative phospho-proteomics reveals the Plasmodium merozoite triggers pre-invasion host kinase modification of the red cell cytoskeleton

The invasive blood-stage malaria parasite - the merozoite - induces rapid morphological changes to the target erythrocyte during entry. However, evidence for active molecular changes in the host cell that accompany merozoite invasion is lacking. Here, we use invasion inhibition assays, erythrocyte resealing and high-definition imaging to explore red cell responses during invasion. We show that although merozoite entry does not involve erythrocyte actin reorganisation, it does require ATP to complete the process. Towards dissecting the ATP requirement, we present an in depth quantitative phospho-proteomic analysis of the erythrocyte during each stage of invasion. Specifically, we demonstrate extensive increased phosphorylation of erythrocyte proteins on merozoite attachment, including modification of the cytoskeletal proteins beta-spectrin and PIEZO1. The association with merozoite contact but not active entry demonstrates that parasite-dependent phosphorylation is mediated by host-cell kinase activity. This provides the first evidence that the erythrocyte is stimulated to respond to early invasion events through molecular changes in its membrane architecture.</p

Effects of a demand-led evidence briefing service on the uptake and use of research evidence by commissioners of health services:A controlled before-and-after study

Background: The Health and Social Care Act 2012 has mandated research use as a core consideration of health service commissioning arrangements. We evaluated whether or not access to a demand-led evidence briefing service improved use of research evidence by commissioners compared with less intensive and less targeted alternatives. Design: Controlled before-and-after study. Setting: Clinical Commissioning Groups (CCGs) in the north of England. Main outcome measures: Change at 12 months from baseline of a CCG’s ability to acquire, assess, adapt and apply research evidence to support decision-making. Secondary outcomes measured individual clinical leads’ and managers’ intentions to use research evidence in decision-making. Methods: Nine CCGs received one of three interventions: (1) access to an evidence briefing service; (2) contact plus an unsolicited push of non-tailored evidence; or (3) an unsolicited push of non-tailored evidence. Data for the primary outcome measure were collected at baseline and 12 months post intervention, using a survey instrument devised to assess an organisation’s ability to acquire, assess, adapt and apply research evidence to support decision-making. In addition, documentary and observational evidence of the use of the outputs of the service was sought and interviews with CCG participants were undertaken. Results: Most of the requests were conceptual; they were not directly linked to discrete decisions or actions but intended to provide knowledge about possible options for future actions. Symbolic use to justify existing decisions and actions were less frequent and included a decision to close a walk-in centre and to lend weight to a major initiative to promote self-care already under way. The opportunity to impact directly on decision-making processes was limited to work to establish disinvestment policies. In terms of impact overall, the evidence briefing service was not associated with increases in CCGs’ capacity to acquire, assess, adapt and apply research evidence to support decision-making, individual intentions to use research findings or perceptions of CCGs’ relationships with researchers. Regardless of the intervention received, at baseline participating CCGs indicated that it felt it was inconsistent in its research-seeking behaviours and its capacity to acquire research remained so at follow-up. The informal nature of decision-making processes meant that there was little or no traceability of the use of evidence. Limitations: Low baseline and follow-up response rates (of 68% and 44%, respectively) and missing data limit the reliability of these findings. Conclusions: Access to a demand-led evidence briefing service did not improve the uptake and use of research evidence by NHS commissioners compared with less intensive and less targeted alternatives. Commissioners appear to be well intentioned but ad hoc users of research. Future work: Further research is required on the effects of interventions and strategies to build individual and organisational capacity to use research. Resource-intensive approaches to providing evidence may best be employed to support instrumental decision-making. Comparative evaluation of the impact of less intensive but targeted strategies on the uptake and use of research by commissioners is warranted. Funding: National Institute for Health Research Health Services and Delivery Research programme

Cadherin-4 plays a role in the development of zebrafish cranial ganglia and lateral line system

We previously reported that cadherin-4 (also called R-cadherin) was expressed by the majority of the developing zebrafish cranial and lateral line ganglia. Cadherin-4 (Cdh4) function in the formation of these structures in zebrafish was studied using morpholino antisense technology. Differentiation of the cranial and lateral line ganglia and lateral line nerve and neuromasts of the cdh4 morphants was analyzed using multiple neural markers. We found that a subset of the morphant cranial and lateral line ganglia were disorganized, smaller, with reduced staining, and/or with altered shape compared to control embryos. Increased cell death in the morphant ganglia likely contributed to these defects. Moreover, cdh4 morphants had shorter lateral line nerves and a reduced number of neuromasts, which was likely caused by disrupted migration of the lateral line primordia. These results indicate that Cdh4 plays a role in the normal formation of the zebrafish lateral line system and a subset of the cranial ganglia. Developmental Dynamics 236:893–902, 2007. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55963/1/21085_ftp.pd

Does sex education before college protect students from sexual assault in college?

Purpose College-bound young people experience sexual assault, both before and after they enter college. This study examines historical risk factors (experiences and exposures that occurred prior to college) for penetrative sexual assault (PSA) victimization since entering college. Methods A cross-sectional study, including an online population-based quantitiative survey with undergraduate students was conducted in spring 2016. Bivariate analyses and multivariable regressions examined risk and protective factors associated with ever experiencing PSA since entering college. Concurrently-collected in-depth ethnographic interviews with 151 students were reviewed for information related to factors identified in the survey. Results In bivariate analyses, multiple historical factors were significantly associated with PSA in college including adverse childhood experiences and having experienced unwanted sexual contact before college (for women) and initiation of alcohol, marijuana, and sexual behaviors before age 18. Significant independent risk factors for college PSA included female gender, experiencing unwanted sexual contact before college, first oral sex before age 18, and “hooking up” (e.g., causual sex or sex outside a committed partnership) in high school. Receipt of school-based sex education promoting refusal skills before age 18 was an independent protective factor; abstinence-only instruction was not. In the ethnographic interviews, students reported variable experiences with sex education before college; many reported it was awkward and poorly delivered. Conclusions Multiple experiences and exposures prior to college influenced the risk of penetrative sexual assault in college. Pre-college comprehensive sexuality education, including skills-based training in refusing unwanted sex, may be an effective strategy for preventing sexual assault in college. Sexual assault prevention needs to begin earlier; successful prevention before college should complement prevention efforts once students enter college

Environmental drivers of Culicoides phenology: how important is species-specific variation when determining disease policy?

Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of adult Culicoides females. Legislative measures therefore allow for the relaxation of ruminant movement restrictions during winter, when nightly light-suction trap catches of Culicoides fall below a threshold (the ‘seasonally vector free period’: SVFP). We analysed five years of time-series surveillance data from light-suction trapping in the UK to investigate whether significant inter-specific and yearly variation in adult phenology exists, and whether the SVFP is predictable from environmental factors. Because female vector Culicoides are not easily morphologically separated, inter-specific comparisons in phenology were drawn from male populations. We demonstrate significant inter-specific differences in Culicoides adult phenology with the season of Culicoides scoticus approximately eight weeks shorter than Culicoides obsoletus. Species-specific differences in the length of the SVFP were related to host density and local variation in landscape habitat. When the Avaritia Culicoides females were modelled as a group (as utilised in the SFVP), we were unable to detect links between environmental drivers and phenological metrics. We conclude that the current treatment of Avaritia Culicoides as a single group inhibits understanding of environmentally-driven spatial variation in species phenology and hinders the development of models for predicting the SVFP from environmental factors. Culicoides surveillance methods should be adapted to focus on concentrated assessments of species-specific abundance during the start and end of seasonal activity in temperate regions to facilitate refinement of ruminant movement restrictions thereby reducing the impact of Culicoides-borne arboviruses

Evaluation of a standard provision versus an autonomy promotive exercise referral programme: rationale and study design

Background The National Institute of Clinical Excellence in the UK has recommended that the effectiveness of ongoing exercise referral schemes to promote physical activity should be examined in research trials. Recent empirical evidence in health care and physical activity promotion contexts provides a foundation for testing the utility of a Self Determination Theory (SDT) -based exercise referral consultation. Methods/Design Design: An exploratory cluster randomised controlled trial comparing standard provision exercise on prescription with a Self Determination Theory-based (SDT) exercise on prescription intervention. Participants: 347 people referred to the Birmingham Exercise on Prescription scheme between November 2007 and July 2008. The 13 exercise on prescription sites in Birmingham were randomised to current practice (n=7) or to the SDT-based intervention (n=6). Outcomes measured at 3 and 6-months: Minutes of moderate or vigorous physical activity per week assessed using the 7-day Physical Activity Recall; physical health: blood pressure and weight; health status measured using the Dartmouth CO-OP charts; anxiety and depression measured by the Hospital Anxiety and Depression Scale and vitality measured by the subjective vitality score; motivation and processes of change: perceptions of autonomy support from the advisor, satisfaction of the needs for competence, autonomy, and relatedness via physical activity, and motivational regulations for exercise. Discussion This trial will determine whether an exercise referral programme based on Self Determination Theory increases physical activity and other health outcomes compared to a standard programme and will test the underlying SDT-based process model (perceived autonomy support, need satisfaction, motivation regulations, outcomes) via structural equation modelling. Trial registration The trial is registered as Current Controlled trials ISRCTN07682833

Acceptability and feasibility of a computer-based application to help Aboriginal and Torres Strait Islander Australians describe their alcohol consumption

We examined acceptability and feasibility of a tablet application (“App”) to record self-reported alcohol consumption among Aboriginal and Torres Strait Islander Australians. Four communities (1 urban; 3 regional/remote) tested the App, with 246 adult participants (132 males, 114 females). The App collected (a) completion time; (b) participant feedback; (c) staff observations. Three research assistants were interviewed. Only six (1.4%) participants reported that the App was “hard” to use. Participants appeared to be engaged and to require minimal assistance; nearly half verbally reflected on their drinking or drinking of others. The App has potential for surveys, screening, or health promotion