Esterase mutation is a mechanism of resistance to antimalarial compounds

Pepstatin is a potent peptidyl inhibitor of various malarial aspartic proteases, and also has parasiticidal activity. Activity of pepstatin against cultured Plasmodium falciparum is highly variable depending on the commercial source. Here we identify a minor contaminant (pepstatin butyl ester) as the active anti-parasitic principle. We synthesize a series of derivatives and characterize an analogue (pepstatin hexyl ester) with low nanomolar activity. By selecting resistant parasite mutants, we find that a parasite esterase, PfPARE (P. falciparum Prodrug Activation and Resistance Esterase) is required for activation of esterified pepstatin. Parasites with esterase mutations are resistant to pepstatin esters and to an open source antimalarial compound, MMV011438. Recombinant PfPARE hydrolyses pepstatin esters and de-esterifies MMV011438. We conclude that (1) pepstatin is a potent but poorly bioavailable antimalarial; (2) PfPARE is a functional esterase that is capable of activating prodrugs; (3) Mutations in PfPARE constitute a mechanism of antimalarial resistance

Transmission cluster of COVID-19 cases from Uruguay: emergence and spreading of a novel SARS-CoV-2 ORF6 deletion

BACKGROUND Evolutionary changes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) include indels in nonstructural, structural, and accessory open reading frames (ORFs) or genes. OBJECTIVES We track indels in accessory ORFs to infer evolutionary gene patterns and epidemiological links between outbreaks. METHODS Genomes from Coronavirus disease 2019 (COVID-19) case-patients were Illumina sequenced using ARTIC_V3. The assembled genomes were analysed to detect substitutions and indels. FINDINGS We reported the emergence and spread of a unique 4-nucleotide deletion in the accessory ORF6, an interesting gene with immune modulation activity. The deletion in ORF6 removes one repeat unit of a two 4-nucleotide repeat, which shows that directly repeated sequences in the SARS-CoV-2 genome are associated with indels, even outside the context of extended repeat regions. The 4-nucleotide deletion produces a frameshifting change that results in a protein with two inserted amino acids, increasing the coding information of this accessory ORF. Epidemiological and genomic data indicate that the deletion variant has a single common ancestor and was initially detected in a health care outbreak and later in other COVID-19 cases, establishing a transmission cluster in the Uruguayan population. MAIN CONCLUSIONS Our findings provide evidence for the origin and spread of deletion variants and emphasise indels’ importance in epidemiological studies, including differentiating consecutive outbreaks occurring in the same health facility

Visual methodologies, sand and psychoanalysis: employing creative participatory techniques to explore the educational experiences of mature students and children in care

Social science research has witnessed an increasing move towards visual methods of data production. However, some visual techniques remain pariah sites because of their association with psychoanalysis; and a reluctance to engage with psychoanalytically informed approaches outside of therapy based settings. This paper introduces the method of ‘sandboxing’, which was developed from the psychoanalytical approach of the ‘world technique’. ‘Sandboxing’ provides an opportunity for participants to create three-dimensional scenes in sand-trays, employing miniature figures and everyday objects. Data is presented from two studies conducted in Wales, UK. The first, exploring mature students’ accounts of higher education, and the second, exploring the educational experiences of children and young people in public care. The paper argues that psychoanalytical work can be adapted to enable a distinctive, valuable and ethical tool of qualitative inquiry; and illustrates how ‘sandboxing’ engendered opportunities to fight familiarity, enabled participatory frameworks, and contributed to informed policy and practice

Development and initial validation of the Influences on Patient Safety Behaviours Questionnaire

YesBackground: Understanding the factors that make it more or less likely that healthcare practitioners (HCPs) will perform certain patient safety behaviors is important in developing effective intervention strategies. A questionnaire to identify determinants of HCP patient safety behaviors does not currently exist. This study reports the development and initial validation of the Influences on Patient Safety Behaviors Questionnaire (IPSBQ) based on the Theoretical Domains Framework. Methods: Two hundred and thirty-three HCPs from three acute National Health Service Hospital Trusts in the United Kingdom completed the 34-item measure focusing on one specific patient safety behavior (using pH as the first line method for checking the position of a nasogastric tube). Confirmatory factor analysis (CFA) was undertaken to generate the model of best fit. Results: The final questionnaire consisted of 11 factors and 23 items, and CFA produced a reasonable fit: χ2 (175) = 345.7, p < 0.001; CMIN/DF = 1.98; GFI = 0.90 and RMSEA = 0.06, as well as adequate levels of discriminant validity, and internal consistency (r = 0.21 to 0.64). Conclusions: A reliable and valid theoretically underpinned measure of determinants of HCP patient safety behavior has been developed. The criterion validity of the measure is still unknown and further work is necessary to confirm the reliability and validity of this measure for other patient safety behaviors

Parental experiences of supporting children with clinically significant post-traumatic distress: a qualitative study of families accessing psychological services

The aim of this study was to investigate the experiences of parents in providing support to their child following trauma exposure in cases where children are experiencing clinically significant levels of post-traumatic distress. Qualitative interviews were conducted with parents whose child was exposed to a trauma and referred for psychological treatment. Parents reported considerable anxiety in coping with their child’s post-traumatic distress. Avoidance of trauma-related discussions was encouraged due to concerns that non-avoidant approaches may worsen children’s post-trauma difficulties. Nonetheless, parents were often sensitive to their child’s distress and offered reassurance and other forms of support. Many barriers existed to accessing psychological treatment, and perceptions of inadequate guidance from therapists on supporting child adjustment contributed to parental distress. The results illustrate the strategies used by parents in supporting their child post-trauma and may assist mental health professionals in providing acceptable guidance to parents following child trauma

Small-molecule inhibition of a depalmitoylase enhances Toxoplasma host-cell invasion.

Although there have been numerous advances in our understanding of how apicomplexan parasites such as Toxoplasma gondii enter host cells, many of the signaling pathways and enzymes involved in the organization of invasion mediators remain poorly defined. We recently performed a forward chemical-genetic screen in T. gondii and identified compounds that markedly enhanced infectivity. Although molecular dissection of invasion has benefited from the use of small-molecule inhibitors, the mechanisms underlying induction of invasion by small-molecule enhancers have never been described. Here we identify the Toxoplasma ortholog of human APT1, palmitoyl protein thioesterase-1 (TgPPT1), as the target of one class of small-molecule enhancers. Inhibition of this uncharacterized thioesterase triggered secretion of invasion-associated organelles, increased motility and enhanced the invasive capacity of tachyzoites. We demonstrate that TgPPT1 is a bona fide depalmitoylase, thereby establishing an important role for dynamic and reversible palmitoylation in host-cell invasion by T. gondii

A clinical and cost-effectiveness trial of a parent group intervention to manage challenging restricted and repetitive behaviours in young children with autism spectrum disorder: study protocol for a randomised controlled trial

Background Restricted and repetitive behaviours vary greatly across the autism spectrum, and although not all are problematic some can cause distress and interfere with learning and social opportunities. We have, alongside parents, developed a parent group based intervention for families of young children with autism, which aims to offer support to parents and carers; helping them to recognise, understand and learn how to respond to their child’s challenging restricted repetitive behaviours. Methods The study is a clinical and cost-effectiveness, multi-site randomised controlled trial of the Managing Repetitive Behaviours (MRB) parent group intervention versus a psychoeducation parent group Learning About Autism (LAA) (n = 250; 125 intervention/125 psychoeducation; ~ 83/site) for parents of young children aged 3–9 years 11 months with a diagnosis of autism. All analyses will be done under intention-to-treat principle. The primary outcome at 24 weeks will use generalised estimating equation (GEE) to compare proportion of children with improved RRB between the MRB group and the LAA group. The GEE model will account for the clustering of children by parent groups using exchangeable working correlation. All secondary outcomes will be analysed in a similar way using appropriate distribution and link function. The economic evaluation will be conducted from the perspective of both NHS costs and family access to local community services. A ‘within trial’ cost-effectiveness analysis with results reported as the incremental cost per additional child achieving at least the target improvement in CGI-I scale at 24 weeks. Discussion This is an efficacy trial to investigate the clinical and cost-effectiveness of a parent group based intervention designed to help parents understand and manage their child’s challenging RRB. If found to be effective, this intervention has the potential to improve the well-being of children and their families, reduce parental stress, greatly enhance community participation and potential for learning, and improve longer-term outcomes

Causes of decoupling between larval supply and settlement and consequences for understanding recruitment and population connectivity

Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Experimental Marine Biology and Ecology 392 (2010): 9-21, doi:10.1016/j.jembe.2010.04.008.Marine broadcast spawners have two-phase life cycles, with pelagic larvae and benthic adults. Larval supply and settlement link these two phases and are crucial for the persistence of marine populations. Mainly due to the complexity in sampling larval supply accurately, many researchers use settlement as a proxy for larval supply. Larval supply is a constraining variable for settlement because, without larval supply, there is no settlement. Larval supply and settlement may not be well correlated, however, and settlement may not consistently estimate larval supply. This paper explores the argument that larval supply (i.e., larval abundance near settlement sites) may not relate linearly to settlement. We review the relationship between larval supply and settlement, from estimates and biases in larval supply sampling, to non-behavioral and behavioral components, including small-scale hydrodynamics, competency, gregarious behavior, intensification of settlement, lunar periodicity, predation and cannibalism. Physical and structural processes coupled with behavior, such as small-scale hydrodynamics and intensification of settlement, sometimes result in under- or overestimation of larval supply, where it is predicted from a linear relationship with settlement. Although settlement is a function of larval supply, spatial and temporal processes interact with larval behavior to distort the relationship between larval supply and settlement, and when these distortions act consistently in time and space, they cause biased estimates of larval supply from settlement data. Most of the examples discussed here suggest that behavior is the main source of the decoupling between larval supply and settlement because larval behavior affects the vertical distribution of larvae, the response of larvae to hydrodynamics, intensification of settlement, gregariousness, predation and cannibalism. Thus, larval behavior seems to limit broad generalizations on the regulation of settlement by larval supply. Knowledge of the relationship is further hindered by the lack of a well founded theoretical relationship between the two variables. The larval supply- settlement transition may have strong general consequences for population connectivity, since larval supply is a result of larval transport, and settlement constrains recruitment. Thus, measuring larval supply and settlement effectively allows more accurate quantification and understanding of larval transport, recruitment and population connectivity.JP would like to thank WHOI Ocean Life Institute for partial funding. FP’s contribution is based upon research supported by the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation

Reading and Ownership

First paragraph: ‘It is as easy to make sweeping statements about reading tastes as to indict a nation, and as pointless.’ This jocular remark by a librarian made in the Times in 1952 sums up the dangers and difficulties of writing the history of reading. As a field of study in the humanities it is still in its infancy and encompasses a range of different methodologies and theoretical approaches. Historians of reading are not solely interested in what people read, but also turn their attention to the why, where and how of the reading experience. Reading can be solitary, silent, secret, surreptitious; it can be oral, educative, enforced, or assertive of a collective identity. For what purposes are individuals reading? How do they actually use books and other textual material? What are the physical environments and spaces of reading? What social, educational, technological, commercial, legal, or ideological contexts underpin reading practices? Finding answers to these questions is compounded by the difficulty of locating and interpreting evidence. As Mary Hammond points out, ‘most reading acts in history remain unrecorded, unmarked or forgotten’. Available sources are wide but inchoate: diaries, letters and autobiographies; personal and oral testimonies; marginalia; and records of societies and reading groups all lend themselves more to the case-study approach than the historical survey. Statistics offer analysable data but have the effect of producing identikits rather than actual human beings. The twenty-first century affords further possibilities, and challenges, with its traces of digital reader activity, but the map is ever-changing