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How parasites develop and survive, and how they stimulate or modulate host immune responses are important in understanding disease pathology and for the design of new control strategies. Microarray analysis and bulk RNA sequencing have provided a wealth of data on gene expression as parasites develop through different life-cycle stages and on host cell responses to infection. These techniques have enabled gene expression in the whole organism or host tissue to be detailed, but do not take account of the heterogeneity between cells of different types or developmental stages, nor the spatial organisation of these cells. Single-cell RNA-seq (scRNA-seq) adds a new dimension to studying parasite biology and host immunity by enabling gene profiling at the individual cell level. Here we review the application of scRNA-seq to establish gene expression cell atlases for multicellular helminths and to explore the expansion and molecular profile of individual host cell types involved in parasite immunity and tissue repair. Studying host-parasite interactions in vivo is challenging and we conclude this review by briefly discussing the applications of organoids (stem-cell derived mini-tissues) to examine host-parasite interactions at the local level, and as a potential system to study parasite development in vitro. Organoid technology and its applications have developed rapidly, and the elegant studies performed to date support the use of organoids as an alternative in vitro system for research on helminth parasites., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Common memory aids for people with dementia at home are recommended. However, rigorous evaluation is lacking, particularly what guidance or support is valued., Objective: To investigate effects of memory aids and guidance by dementia support practitioners (DSPs) for people in early-stage dementia through a pragmatic, randomised controlled trial., Methods: Of 469 people with mild-to-moderate dementia and their informal carers, 468 were randomised to a DSP with memory aids or to usual care plus existing dementia guide. Allocation was stratified by Trust/Health Board; time since first attendance at memory service; gender; age; and living with primary carer or not. Primary outcome was Bristol Activities of Daily Living Scale (BADLS) Score at 3 and 6 months (primary end-point). Secondary outcomes for people with dementia: quality of life (CASP-19; DEMQOL); cognition and functioning (Clinical Dementia Rating Scale; S-MMSE); capability (ICECAP-O); social networks (LSNS-R); and instrumental daily living activities (R-IDDD). Secondary outcomes for carers: psychological health (GHQ-12); sense of competence (SSCQ)., Results: DSPs were successfully trained, compliance was good and welcomed by participants. Mean 6 months BADLS Score increased to 14.6 (SD: 10.4) in intervention and 12.6 (SD: 8.1) in comparator, indicative of greater dependence in the activities of daily living. Adjusted between-group difference was 0.38 (95% CI: -0.89 to 1.65, p=0.56). Though this suggests greater dependency in the intervention group the difference was not significant. No differences were found in secondary outcomes., Conclusions: This intervention did not maintain independence in the activities of daily living with no improvement in other outcomes for people with dementia or carers., Trial Registration Number: Current Controlled Trials ISRCTN12591717., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Objectives: The DESCANT (Dementia Early Stage Cognitive Aids New Trial) intervention provided a personalised care package designed to improve the cognitive abilities, function and well-being of people with early-stage dementia and their carers, by providing a range of memory aids, together with appropriate training and support. This sub-study aimed to assess implementation and identify contextual factors potentially associated with participant outcomes., Method: A mixed-methods approach was adopted alongside the pragmatic randomised trial. Data were obtained from intervention records and interviews with five dementia support practitioners across seven National Health Service Trusts in England and Wales. A reporting framework was constructed from available literature and data assessed by descriptive statistics and thematic analysis., Results: Participation and engagement was high with 126 out of 128 participants completing the intervention with packages tailored to individual participants. Misplacing items and poor orientation to date and time were common areas of need. Memory aids frequently supplied included orientation clocks (91%), whiteboards (60%), calendars (43%) and notebooks (32%), plus bespoke items. Intervention duration and timing were broadly consistent with expectations. Variation reflected participants' needs, circumstances and preferences. Qualitative findings suggested a potentially positive impact on the well-being of people with dementia and their carers. Issues associated with successful roll-out of the intervention are explored in the discussion., Conclusion: Successful implementation increased confidence in future findings of the randomised trial. Depending on these, DESCANT may prove a scalable intervention with potential to improve the function and quality of life of people with dementia and their carers.

Helminth parasite infections of humans and livestock are a global health and economic problem. Resistance of helminths to current drug treatment is an increasing problem and alternative control approaches, including vaccines, are needed. Effective vaccine design requires knowledge of host immune mechanisms and how these are stimulated. Mouse models of helminth infection indicate that tuft cells, an unusual type of epithelial cell, may 'sense' infection in the small intestine and trigger a type 2 immune response. Currently nothing is known of tuft cells in immunity in other host species and in other compartments of the gastrointestinal (GI) tract. Here we address this gap and use immunohistochemistry and single cell RNA-sequencing to detail the presence and gene expression profile of tuft cells in sheep following nematode infections. We identify and characterize tuft cells in the ovine abomasum (true stomach of ruminants) and show that they increase significantly in number following infection with the globally important nematodes Teladorsagia circumcincta and Haemonchus contortus . Ovine abomasal tuft cells show enriched expression of tuft cell markers POU2F3, GFI1B, TRPM5 and genes involved in signaling and inflammatory pathways. However succinate receptor SUCNR1 and free fatty acid receptor FFAR3 , proposed as 'sensing' receptors in murine tuft cells, are not expressed, and instead ovine tuft cells are enriched for taste receptor TAS2R16 and mechanosensory receptor ADGRG6. We also identify tuft cell sub-clusters at potentially different stages of maturation, suggesting a dynamic process not apparent from mouse models of infection. Our findings reveal a tuft cell response to economically important parasite infections and show that while tuft cell effector functions have been retained during mammalian evolution, receptor specificity has diverged. Our data advance knowledge of host-parasite interactions in the GI mucosa and identify receptors that may potentiate type 2 immunity for optimized control of parasitic nematodes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Hildersley, McNeilly, Gillan, Otto, Löser, Gerbe, Jay, Maizels, Devaney and Britton.)