The role of tissue type, sampling and nucleic acid purification methodology on the inferred composition of Pacific oyster (Crassostrea gigas) microbiome.

AIMS: This study evaluated methods to sample and extract nucleic acids from Pacific oysters to accurately determine the microbiome associated with different tissues. METHODS AND RESULTS: Samples were collected from haemolymph, gill, gut and adductor muscle, using swabs and homogenates of solid tissues. Nucleic acids were extracted from fresh and frozen samples using three different commercial kits. The bacterial DNA yield varied between methods (P < 0·05) and each tissue harboured a unique microbiota, except for gill and muscle. Higher bacterial DNA yields were obtained by swabbing compared to tissue homogenates and from fresh tissues compared to frozen tissues, without impacting the bacterial community composition estimated by 16S rRNA gene (V1-V3 region) sequencing. Despite the higher bacterial DNA yields with QIAamp® DNA Microbiome Kit, the E.Z.N.A.® Mollusc DNA Kit identified twice as many operational taxonomic units (OTUs) and eliminated PCR inhibition from gut tissues. CONCLUSIONS: Sampling and nucleic acid purification substantially affected the quantity and diversity of bacteria identified in Pacific oyster microbiome studies and a fit-for-purpose strategy is recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: Accurate identification of Pacific oyster microbial diversity is instrumental for understanding the polymicrobial aetiology of Pacific oyster mortality diseases which greatly impact oyster production.

"Fat is really a four-letter word": Exploring weight-related communication best practices in children with and without disabilities and their caregivers.

BACKGROUND: Health care professionals play a critical role in preventing and managing childhood obesity, but the American Academy of Pediatrics recently stressed the importance of using sensitive and nonstigmatizing language when discussing weight with children and families. Although barriers to weight-related discussions are well known, there are few evidence-based recommendations around communication best practices. Disability populations in particular have previously been excluded from work in this area. The objectives were to present the findings of a recent scoping review to children with and without disabilities and their caregivers for their reactions; and to explore the experiences and perceptions of the children and their caregivers regarding weight-related communication best practices. METHODS: Focus group and individual interviews were conducted with 7-18-year olds with and without disabilities and their caregivers. The interview guide was created using findings from a recent scoping review of weight-related communication best practices. Inductive thematic analysis was employed. RESULTS: Eighteen children (9 boys; 7 children with disabilities) and 21 caregivers (17 mothers, 1 step-father, 3 other caregivers) participated in 8 focus group and 7 individual interviews. Preferred communication strategies were similar across those with and without disabilities, although caregivers of children with autism spectrum disorder endorsed more concrete approaches. Discussions emphasizing growth and health were preferred over weight and size. Strengths-based, solution-focused approaches for weight conversations were endorsed, although had not been widely experienced. CONCLUSION: Perceptions of weight-related communication were similar across stakeholder groups, regardless of children's disability or weight status. Participants generally agreed with the scoping review recommendations, suggesting that they apply broadly across different settings and populations; however, tailoring them to specific circumstances is critical. Empirical evaluations are still required to examine the influence of weight-related communication on clinically important outcomes, including behaviour change and family engagement in care.

The internet as a source of support for youth with chronic conditions: A qualitative study.

BACKGROUND: Adolescents living with chronic conditions often portray themselves as "healthy" online, yet use the Internet as one of their top sources of health information and social communication. There is a need to develop online support programs specific to adolescents with chronic conditions in order to provide a private space to discuss concerns. This paper endeavors to increase our understanding of the online support needs and wants of these adolescents and their interest in and preferences for an online support program. METHODS: A qualitative descriptive study using semistructured interviews was completed. Stratified purposive sampling was utilized to ensure a representative sample based on age and diagnosis. English speaking adolescents (aged 12-18 years) diagnosed with a chronic condition were recruited from clinic and inpatient areas across 3 paediatric hospitals in Canada. RESULTS: Thirty-three participants aged 15.3 ± 1.8 years (64% female) completed the study. The main topics identified were (a) the purpose of current online activity, (b) the benefits and challenges of existing online supports, and (c) a description of ideal online resources. The purpose of online activity was social networking, information, online gaming, and social support. When accessing health information online, participants prioritized websites that were easy to access and understand despite the trustworthiness of the site. The reported benefits and challenges varied across participants with many areas perceived as both a benefit and a challenge. The majority of participants were interested in participating in an online support program that included both accurate disease-related information and a community of other adolescents to provide social support. CONCLUSIONS: Adolescents with chronic conditions are interested in online support that encompasses health information and social support that is flexible and easy to navigate. Findings can be used to develop or adapt existing online support programs for adolescents with chronic conditions to help increase engagement and utilization.

Parents' early healthcare transition experiences with preterm and acutely ill infants: a scoping review.

BACKGROUND: Parents undergo multiple transitions following the birth of an ill infant: their infant's illness-health trajectory, neonatal intensive care unit hospitalization and transfers from one healthcare setting to another, while also transitioning to parenthood. The objective of this review was to map and synthesize evidence on the experiences and needs of parents of preterm or ill infants as they transition within and between healthcare settings following birth. METHODS: The scoping review followed Arskey and O'Malley's () framework, enhanced by Levac et al. (). Relevant studies were identified through a comprehensive search strategy of scientific and grey literature databases, online networks, Web of Science and citation lists of relevant articles. Inclusion criteria encompassed a focus on infants undergoing a healthcare transition, and the experiences and needs of parents during transition. Studies were appraised for design quality, and data relevant to parent experiences were extracted and underwent thematic analysis. RESULTS: A total of 7773 records were retrieved, 90 full texts reviewed and 11 articles synthesized that represented a total sample of 435 parents of preterm or ill infants. Parents reported on their experiences in response to their infant's transition within and between hospitals and across levels of neonatal intensive care unit, intermediate and community hospital care. Ten studies used qualitative research methods, while one employed quantitative survey methods. Four key themes were identified: that of parent distress throughout transition, parenting at a distance, sources of stress and sources of support. Parents' stress resulted from not being informed or involved in the transition decision, inadequate communication and perceived differences in cultures of care across healthcare settings. CONCLUSIONS: Opportunities to improve parents' early transition experiences include enhanced engagement, communication, information-sharing and shared decision-making between health care providers and parents. Future areas of research should focus on early transition interventions to advance parent capacity, confidence and closeness as the primary nurturer.

Implementation of an inter-agency transition model for youth with spina bifida.

BACKGROUND: To address gaps in transfer of care and transition support, a paediatric hospital and adult community health care centre partnered to implement an inter-agency transition model for youth with spina bifida. Our objective was to understand the enablers and challenges experienced in the implementation of the model. METHODS: Using a descriptive, qualitative design, we conducted semi-structured interviews, in-person or over the phone, with 12 clinicians and nine key informants involved in implementing the spina bifida transition model. We recruited all 21 participants from an urban area of Ontario, Canada. RESULTS: Clinicians and key informants experienced several enablers and challenges in implementing the spina bifida transition model. Enablers included dedicated leadership, advocacy, funding, inter-agency partnerships, cross-appointed staff and gaps in co-ordinated care to connect youth to adult services. Challenges included gaps in the availability of adult specialty services, limited geographical catchment of adult services, limited engagement of front-line staff, gaps in communication and role clarity. CONCLUSIONS: Although the transition model has realized some initial successes, there are still many challenges to overcome in transferring youth with spina bifida to adult health care and transitioning to adulthood.

Comparison of recto-anal mucosal swab and faecal culture for the detection of Escherichia coli O157 and identification of super-shedding in a mob of Merino sheep.

We compared the use of recto-anal mucosal swab (RAMS) culture and faecal culture for the detection of E. coli O157 in a mob of Merino sheep. Fifty Merino wethers and maiden ewes housed in indoor pens were sampled on five occasions. We detected E coli O157 in 32% (16/50) of sheep, with weekly prevalence ranging from 4% (2/50) to 16% (8/50). Overall, 12·5% (2/16) were detected by RAMS culture only, and 37·5% (6/16) were detected by faecal culture only. The level of agreement between the two sampling methods was moderate [kappa statistic = 0·583, 95% confidence interval (CI) 0·460-0·707]. The relative sensitivities of RAMS and faecal culture were 67% (95% CI 41-86) and 57% (95% CI 34-77), respectively. We identified four super-shedding sheep using direct faecal culture. Although the majority of culture-positive sheep were detected at one sampling point only, 3/4 super-shedding sheep were culture-positive at two sampling points, and 1/4 was culture-positive at four sampling points. Persistent culture positivity may indicate sheep that could be considered 'super-shedders' at some point. The use of immunomagnetic separation further improved the rate of detection of E. coli O157, which was isolated from 1/34 animals that were previously negative by enrichment culture alone. A significant difference between sampling weeks was detected for both faecal (P = 0·021) and RAMS (P = 0·006), with the prevalence at the mid-point of sampling (week 4) significantly (P < 0·05) higher than at the beginning or end of the study. Study conditions (penned sheep) might have been responsible for the high prevalence and the epidemic pattern of infection observed, and could serve as a future model for studies of E. coli O157 transmission, shedding and super-shedding in sheep.

A qualitative exploration of the experiences of children with spina bifida and their parents around incontinence and social participation.

BACKGROUND: Urinary incontinence is frequently experienced by children with spina bifida, putting them at increased risk for low self-esteem and impacting upon participation in home, school and leisure activities. However, little is known about children's experiences of these continence issues. OBJECTIVE: This study explored the experiences of children and young people with spina bifida around continence issues, social participation and peer relationships, in order to identify potential areas of support healthcare professionals can provide. METHODS: Children and youth aged 6-18 years with diagnoses of spina bifida and neurogenic bladder and their parents were invited to participate in semi-structured interviews. Descriptive thematic analysis was employed. RESULTS: Eleven children (with a range of mobility levels, types of spina bifida and degrees of bladder control) and their parents participated in the study. Three broad themes were identified, which encompassed the following: (1) normal versus different; (2) independence, ownership and the road to continence; and (3) peer relationships and acceptance. DISCUSSION: The experiences discussed by the children and parents in this study ranged from minimal impact of incontinence on their day-to-day living to significant social isolation and rejection. The stigma of incontinence was apparent in all interviews. Children and youth who were able to control their bladder with minimal accidents had greater independence and more opportunities for social participation. Healthcare professionals need to take into account that parents and their children may differ in attitudes and desires about the management of incontinence.

A retrospective study of past graduates of a residential life skills program for youth with physical disabilities.

BACKGROUND: Young people with physical disabilities experience issues regarding employment, schooling, independent living and establishing meaningful personal relationships. A lack of life skills has been recognized as an important factor contributing to this lag. The Independence Program (TIP) is a short-term residential life skills program that aims to equip youth with the foundational life skills required to assume adult roles. This study retrospectively examined the achievements, skills acquired and program attributions of youth and young adults who took part in this three-week immersive teen independence program over a 20-year period. METHODS: A total of 162 past graduates were invited to take part, with 78 doing so (a 48% response rate). These past graduates completed an online survey assessing objective outcomes such as employment and independent living; subjective outcomes such as feeling in control and living meaningful lives; and reflections on skills acquired, opportunities experienced and attributions to TIP. RESULTS: The majority of respondents were female (71%), had a diagnosis of cerebral palsy (55%) and ranged from 20 to 35 years of age (92%). Despite a range of outcomes related to the achievement of adult roles, high levels of life satisfaction and overall quality of life were reported. Nearly every respondent reported using the skills they learned at the program in their lives afterwards and a high percentage attributed the acquisition and consolidation of core life skills to participating in this intensive immersive program. CONCLUSIONS: Although causality cannot be assumed, respondents reflected very positively on the opportunities provided by TIP to develop their independent living and life skills, extend their social networks and understand their strengths and weaknesses. Such findings validate the importance of targeted skill development to assist young people with physical disabilities in attaining their life goals and encourage focused investigations of key features in program design.

A four-part ecological model of community-focused therapeutic recreation and life skills services for children and youth with disabilities.

AIM: This article presents a four-part model of community-focused therapeutic recreation and life skills services for children's rehabilitation centres. METHOD AND RESULTS: The model is based on 15 years of clinical and management practice in a Canadian context combined with evidence from the literature on community-focused service delivery. The model incorporates an ecological approach and principles from models of therapeutic recreation, community capacity building, and health promotion, as well as client/family-centred care. The four pillars of the model reflect a set of integrated services and principles designed to support the participation of children and youth with disabilities in community activities. The pillars involve providing community outreach services, providing community development services, sharing physical and educational resources with community partners, and promoting the organization as a community facility that provides adapted physical space and specialized instruction. The lessons learned in implementing the model are discussed, including the importance of ensuring the sustainability of community recreation programmes. CONCLUSIONS: The model will be of use to managers and service organizations seeking to develop an integrated programme of community-focused therapeutic recreation and life skills services based on a collaborative capacity-building approach.

'It is life threatening but I don't mind'. A qualitative study using photo elicitation interviews to explore adolescents' experiences of renal replacement therapies.

BACKGROUND: Renal replacement therapy (RRT) transforms the life prospects of young people with established renal failure. However, these treatments can have significant physiological and psychological implications for adolescents as they prepare to transition into adulthood. Health policies increasingly emphasize children and youth's active participation and consultation as users of health services, yet studies infrequently seek their experiences directly. METHODS: Adolescents receiving RRT in a large UK teaching hospital took photographs illustrating the impact of their condition and treatment on their lives. Qualitative photo elicitation interviews were conducted to explore the significance of the images and the young person's experiences. Interviews were analysed using descriptive thematic analysis. RESULTS: Ten young people aged 13-17 years participated. Themes identified were: (1) understanding and acceptance of treatment; (2) living in a non-functioning body; (3) impact upon daily life; (4) sources of support. Young people found treatments challenging and experienced significant impact on relationships and daily routines. Yet, health was prioritized over body image and participants demonstrated great emotional resilience. Young people valued support from family and friends, although were wary of disclosing their condition in case it resulted in being highlighted as different. Young people reported hospital staff as being caring and professional, but their biggest virtue appeared to be their willingness to treat the young people as 'normal'. CONCLUSIONS: Young people engaged readily with the research, and frankly described the impact of RRT on their everyday lives. Service providers must ensure that adolescents' developmental needs are met as traditional tasks of adolescence may lose priority. However, it is also clear that young people's ability to cope with treatments should not be underestimated.

Strategies for improving disability awareness and social inclusion of children and young people with cerebral palsy.

BACKGROUND: Children and youth with disabilities are at a higher risk of being socially excluded or bullied while at school compared with their typically developing peers. This study explored disabled children's suggestions for improving social inclusion. METHODS: Fifteen children with cerebral palsy were interviewed or took part in a group discussion about social inclusion and bullying. All interviews and focus groups were audio-recorded and transcribed verbatim. RESULTS: The children and youth described several strategies to help improve social inclusion at school including: (1) disclosure of condition and creating awareness of disability; (2) awareness of bullying; (3) developing a peer support network and building self-confidence; and (4) suggestions on what teachers can do. CONCLUSIONS: It is recommended that children's suggestions be considered within the classroom context to enhance the social inclusion and participation of children with disabilities.

The severity of footrot lesions induced by aprV2-positive strains of Dichelobacter nodosus varies between strains.

OBJECTIVES: The primary objective of this study was to evaluate the clinical virulence of aprV2-positive lesser virulent field isolates of footrot bacteria Dichelobacter nodosus in comparison with an aprV2-positive clinically virulent reference strain. Correlations between the clinical expression of the disease and the presence of aprV2 (detected using PCR tests) have been inconsistent. A second objective was to evaluate the elimination of D. nodosus following treatment of sheep as some strains of D. nodosus have been reported to be difficult to eliminate. METHODS: The virulence of three aprV2-positive field isolates of D. nodosus which had lesser virulent phenotypes, and an aprV2-positive virulent reference strain was evaluated in a sheep trial using a pasture-based experimental infection model. In the second phase of the study, treatments including footbathing and a long-acting antibiotic were administered and their efficacy in elimination of these strains was evaluated. RESULTS: Severe underrun (score 4) lesions developed in sheep infected with the aprV2-positive virulent reference strain but not in sheep infected with the field isolates; they had mild lesions (score 2 or 3). The three field isolates and the virulent reference strain of D. nodosus were eliminated by intensive foot bathing and antibiotic therapy in combination with housing the animals in dry conditions post-treatment. CONCLUSION: The results suggest that the presence of aprV2 gene in isolates of D. nodosus may not be a reliable indicator of virulence and that further investigation of the factors that determine clinical virulence is required. While the treatment regime was successful, based on a range of considerations, the use of such an intensive treatment involving antibiotics should be limited to small groups of high-value animals, such as rams.

Atomic force microscopy investigation of vaccinia virus structure.

Vaccinia virus was treated in a controlled manner with various combinations of nonionic detergents, reducing agents, and proteolytic enzymes, and successive products of the reactions were visualized using atomic force microscopy (AFM). Following removal of the outer lipid/protein membrane, a layer 20 to 40 nm in thickness was encountered that was composed of fibrous elements which, under reducing conditions, rapidly decomposed into individual monomers on the substrate. Beneath this layer was the virus core and its prominent lateral bodies, which could be dissociated or degraded with proteases. The core, in addition to the lateral bodies, was composed of a thick, multilayered shell of proteins of diverse sizes and shapes. The shell, which was readily etched with proteases, was thoroughly permeated with pores, or channels. Prolonged exposure to proteases and reductants produced disgorgement of the viral DNA from the remainders of the cores and also left residual, flattened, protease-resistant sacs on the imaging substrate. The DNA was readily visualized by AFM, which revealed some regions to be "soldered" by proteins, others to be heavily complexed with protein, and yet other parts to apparently exist as bundled, naked DNA. Prolonged exposure to proteases deproteinized the DNA, leaving masses of extended, free DNA. Estimates of the interior core volume suggest moderate but not extreme compaction of the genome.

Heterogeneous and epitaxial nucleation of protein crystals on mineral surfaces.

Fifty different mineral samples were tested as potential heterogeneous or epitaxial nucleants for four commonly crystallized proteins. It was found, by conventional protein crystallization techniques, that for each protein there was a set of mineral substrates that promoted nucleation of crystals at lower critical levels of supersaturation than required for spontaneous growth. Numerous examples, involving all four proteins, were observed of modification of crystal habit and, in some cases, unit cell properties promoted by the presence of the mineral nucleants. In at least one case, the growth of lysozyme on the mineral apophyllite, it was shown by lattice analysis and x-ray diffraction that the nucleation and growth of the protein crystal on the mineral was likely to involve a direct lattice match.

The mechanism of binding of a polynucleotide chain to pancreatic ribonuclease.

The crystalline complex of pancreatic ribonuclease (RNase) with oligomers of d(pA)4 has been solved by x-ray diffraction methods and refined by standard procedures to a conventional crystallographic R factor of 0.22 at 2.5 angstrom resolution. The asymmetric unit is a complex of one RNase molecule associated with four d(pA)4 oligomers. Although the DNA in this complex is segmented, and therefore shows some discontinuities, it nevertheless traces a continuous path 12 nucleotides in length that passes through the active site cleft of the enzyme and over the surface of the protein. The DNA makes a series of eight to nine electrostatic bonds between its phosphate groups and lysine and arginine residues on the protein, as well as specific chemical interactions at the active site. The path described by the sequence of nucleotides is likely to be that taken by an extended polynucleotide chain when it is bound by the enzyme.

Three-dimensional structure of yeast phenylalanine transfer RNA: folding of the polynucleotide chain.

At 4 A resolution the polynucleotides in yeast phenylalanine transfer RNA are seen in a series of electron dense masses about 5.8 A apart. These peaks are probably associated with the phosphate groups, while lower levels of electron density between segments of adjacent polynucleotide chains are interpreted as arising from hydrogen-bonded purine-pyrimidine base pairs. It is possible to trace the entire polynucleotide chain with only two minor regions of ambiguity. The polynucleotide chain has a secondary structure consistent with the cloverleaf conformation; however, its folding is different from that proposed in any model. The molecule is made of two double-stranded helical regions oriented at right angles to each other in the shape of an L. One end of the L has the CCA acceptor; the anticodon loop is at the other end, and the dihydrouridine and TpsiC loops form the corner.

Three-dimensional tertiary structure of yeast phenylalanine transfer RNA.

The 3-angstrom electron density map of crystalline yeast phenylalanine transfer RNA has provided us with a complete three-dimensional model which defines the positions of all of the nucleotide residues in the moleclule. The overall features of the molecule are virtually the same as those seen at a resolution of 4 angstroms except that many additional details of tertiary structure are now visualized. Ten types of hydrogen bonding are identified which define the specificity of tertiary interactions. The molecule is also stabilized by considerable stacking of the planar purines and pyrimidines. This tertiary structure explains, in a simple and direct fashion, chemical modification studies of transfer RNA. Since most of the tertiary interactions involve nucleotides which are common to all transfer RNA 's, it is likely that this three-dimensional structure provides a basic pattern of folding which may help to clarify the three-dimensional structure of all transfer RNA's.

Selective transport of polymeric immunoglobulin A in bile. Quantitative relationships of monomeric and polymeric immunoglobulin A, immunoglobulin M, and other proteins in serum, bile, and saliva.

In 17 adults, serum, hepatic bile, and saliva samples were analyzed for their sedimentation profile of IgA and secretory component (SC), and for their concentrations of albumin, orosomucoid, transferrin, IgG, IgA, alpha 2-macroglobulin (alpha 2M), IgM, and SC. Polymeric IgA(p-IgA) averaged 13% (50-700 micrograms/ml) of total IgA in serum, 70% (43-88%) in bile, and 93% (74-98%) in saliva. Most of the p-IgA in bile sedimented with SC, which also occurred free (8-44%), and with IgM. In bile, albumin (155-1,485 micrograms/ml) was the predominant protein, followed by IgG (32-480 micrograms/ml), and total IgA (37-209 micrograms/ml). In saliva, p-IgA (72-902 micrograms/ml) predominated, followed by albumin (16-385 micrograms/ml) and IgG (9-178 micrograms/ml). Secretion-to-serum albumin-relative concentration ratios (S/S-ARCR = 1 for albumin) in bile averaged 22 for p-IgA, 1.91 for IgM, 1.28 for monomeric IgA (m-IgA), 0.70 for IgG, and 0.57 for alpha 2M, indicating for p-IgA, IgM, and to a lesser extent for m-IgA, a selective excretion into bile. In saliva, a 16-fold greater selective excretion of p-IgA (mean S/S-ARCR = 354) was found. Labeled m- and p-IgA were injected intravenously into five patients. Specific activities indicated that for p-IgA 50% was serum derived in bile, as compared with 2% in saliva, and to 85% for m-IgA in bile. In the patient with the highest excretion of 125I-p-IgA in bile, only 2.8% of the injected dose was recovered in bile within 24 h after injection. Compared with rats and rabbits, the serum-to-bile transport of p-IgA in humans is much smaller.

Satellite tobacco mosaic virus RNA: structure and implications for assembly.

The initial appearance of 45% of the single-stranded RNA of satellite tobacco mosaic virus in electron density maps suggested the entire RNA conformation could be delineated. Subsequent work has localized nearly 80% of the RNA as stem-loop elements. Connection of the stem-loops in the most efficient manner produces a persuasive model for the encapsidated RNA. This arrangement has significant implications for virus assembly and for the essential role of RNA.

Communicating with children and families about obesity and weight-related topics: a scoping review of best practices.

BACKGROUND: Healthcare professionals have called for direction on how best to communicate about weight-related topics with children and families. Established scoping review methodology was used to answer the question: 'How can healthcare professionals best communicate with children and their families about obesity and weight-related topics?' METHODS: We searched four scientific databases, two grey literature repositories and 14 key journals (2005-2016). Inclusion criteria were (i) children up to and including 18 years of age and/or their parents; (ii) communication about healthy weight, overweight, obesity or healthy/active living; and (iii) healthcare setting. RESULTS: Thirty-two articles were included. Evidence-based best practices were largely absent from the literature, although the following guiding principles were identified: (i) include all stakeholders in discussions; (ii) raise the topic of weight and health early and regularly; (iii) use strengths-based language emphasizing health over weight; (iv) use collaborative goal-setting to engage children and parents and (v) augment discussions with appropriate tools and resources. Guidance on how to implement these principles and how to negotiate relevant contextual factors (e.g. age, culture and disability) is still needed. CONCLUSION: Despite agreement on a number of guiding principles, evidence-based weight-related communication best practices are lacking. Rigorous, empirical evaluations of communication approaches are urgently required, especially those that include children's perspectives.