Advancing Strongyloides omics data: bridging the gap with Caenorhabditis elegans.

Among nematodes, the free-living model organism Caenorhabditis elegans boasts the most advanced portfolio of high-quality omics data. The resources available for parasitic nematodes, including Strongyloides spp., however, are lagging behind. While C. elegans remains the most tractable nematode and has significantly advanced our understanding of many facets of nematode biology, C. elegans is not suitable as a surrogate system for the study of parasitism and it is important that we improve the omics resources available for parasitic nematode species. Here, we review the omics data available for Strongyloides spp. and compare the available resources to those for C. elegans and other parasitic nematodes. The advancements in C. elegans omics offer a blueprint for improving omics-led research in Strongyloides. We suggest areas of priority for future research that will pave the way for expansions in omics resources and technologies. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'.

Strongyloides questions-a research agenda for the future.

The Strongyloides genus of parasitic nematodes have a fascinating life cycle and biology, but are also important pathogens of people and a World Health Organization-defined neglected tropical disease. Here, a community of Strongyloides researchers have posed thirteen major questions about Strongyloides biology and infection that sets a Strongyloides research agenda for the future. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'.

Mechanism of outside-in {alpha}IIb{beta}3-mediated activation of human platelets by the colonizing Bacterium, Streptococcus gordonii.

OBJECTIVE: To better understand the mechanism of platelet recruitment and activation by Streptococcus gordonii. The oral bacterium Streptococcus gordonii, is amongst the most common pathogens isolated from infective endocarditis patients, and has the property of being able to activate platelets, leading to thrombotic complications. The mechanism of platelet recruitment and activation by S. gordonii is poorly understood. METHODS AND RESULTS: Infective endocarditis is a bacterial infection of the heart valves that carries a high risk of morbidity and mortality. The oral bacterium, S gordonii, is among the most common pathogens isolated from patients with infective endocarditis and is able to activate platelets, leading to thrombotic complications. Platelets interact with S gordonii via glycoprotein Ibα- and α(IIb)ß(3)-recognizing S gordonii surface proteins haemaglutitin salivary antigen (Hsa) and platelet adherence protein A, respectively. The inhibition of glycoprotein Ibα or α(IIb)ß(3) using blocking antibodies or deletion of S gordonii Hsa or platelet adherence protein A significantly reduces platelet adhesion. Immunoreceptor tyrosine-based activation motif (ITAM)-containing proteins have recently played a role in transmitting activating signals into platelets. Platelet adhesion to immobilized S gordonii resulted in tyrosine phosphorylation of the ITAM-bearing receptor, FcγRIIa, and phosphorylation of downstream effectors (ie, spleen tyrosine kinase [Syk] and phospholipase C [PLC]-γ2). Tyrosine phosphorylation of FcγRIIa resulted in platelet-dense granule secretion, filopodial and lamellipodial extension, and platelet spreading. Inhibition of FcγRIIa ablated both dense granule release and platelet spreading. CONCLUSIONS: Streptococcus gordonii binding to the α(IIb)ß(3)/FcγRIIa integrin/ITAM signaling complex results in platelet activation that likely contributes to the thrombotic complications of infective endocarditis.

Methadone dosing and prescribed medication use in a prospective cohort of opioid-dependent pregnant women.

AIMS: This study aimed to (i) describe methadone dosing before, during and after pregnancy, (ii) to compare the incidence of neonatal abstinence syndrome (NAS) between those with dose decreases and those with steady or increasing doses and (iii) to describe prescribed medication use among opioid-dependent pregnant women. DESIGN: Prospective cohort study. SETTING: Two Irish tertiary care maternity hospitals. PARTICIPANTS: A total of 117 pregnant women on methadone maintenance treatment (MMT) recruited between July 2009 and July 2010. MEASUREMENTS: Electronic dispensing records from addiction clinics and the Primary Care Reimbursement Service were used to determine methadone doses and dispensed medications in the year preceding and the month following delivery. The Finnegan score was used to determine need for medical treatment of NAS. FINDINGS: Of the 117 participants, sufficient dosing data were available for 89 women treated with MMT throughout pregnancy; 36 (40.4%) had their dose decreased from a mean pre-pregnancy dose of 73.3 mg [standard deviation (SD) 25.5] to a third-trimester dose of 58.0 mg (SD 26.0). The corresponding figures for those with increased doses (n = 31, 34.8%) were 70.7 mg (SD 25.3) and 89.7 mg (SD 21.0), respectively. The incidence of medically treated NAS did not differ between dosage groups. Antidepressants were dispensed for 29 women (25.7%) during pregnancy, with the rate decreasing from pre-pregnancy to postpartum. Benzodiazepines were prescribed for 43 women (38.0%). CONCLUSION: In the Irish health service, opioid-dependent women frequently have their methadone dose decreased during pregnancy but this does not appear to affect the incidence of the neonatal abstinence syndrome in their babies.

Transcriptional response of Candida parapsilosis following exposure to farnesol.

In Candida albicans, the quorum-sensing molecule farnesol inhibits the transition from yeast to hyphae but has no effect on cellular growth. We show that the addition of exogenous farnesol to cultures of Candida parapsilosis causes the cells to arrest, but not at a specific stage in the cell cycle. The cells are not susceptible to additional farnesol. However, the cells do eventually recover from arrest. Unlike in C. albicans, in C. parapsilosis sterols are localized to the tips of budding cells, and this polarization is disrupted by the addition of farnesol. We used the results of a genome sequence survey to design and manufacture partial genomic microarrays that were applied to determining the transcriptional response of C. parapsilosis to the presence of exogenous farnesol. In both C. albicans and C. parapsilosis, exposure to farnesol results in increased expression of the oxidoreductases GRP2 and ADH7 and altered expression of genes involved in sterol metabolism. There is no effect on expression of C. parapsilosis orthologs of genes involved in hyphal growth in C. albicans. Farnesol therefore differs significantly in its effects on C. parapsilosis and C. albicans.

Solution-processed anodes from layer-structure materials for high-efficiency polymer light-emitting diodes.

The development of low-cost, large-area electronic applications requires the deposition of active materials in simple and inexpensive techniques at room temperature, properties usually associated with polymer films. In this study, we demonstrate the integration of solution-processed inorganic films in light-emitting diodes. The layered transition metal dichalcogenide (LTMDC) films are deposited through Li intercalation and exfoliation in aqueous solution and partially oxidized in an oxygen plasma generator. The chemical composition and thickness of the LTMDC and corresponding transition metal oxide (TMO) films are investigated by X-ray photoelectron spectroscopy. The morphology and topography of the films are studied by atomic force microscopy. X-ray powder diffraction is used to determine the orientation of the LTMDC film. Finally, the LTMDC and their corresponding oxides are utilized as hole-injecting and electron-blocking materials in polymer light-emitting diodes with the general structure ITO/LTMDC/TMO/polyfluorene/Ca/Al. Efficient hole injection and electron blocking by the inorganic layers result in outstanding device performance and high efficiency.