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Abstract Biofilms are surface-associated communities of bacteria that grow in a self-produced matrix of polysaccharides, proteins, and extracellular DNA (eDNA). Sub-minimal inhibitory concentrations (sub-MIC) of antibiotics induce biofilm formation, potentially as a defensive response to antibiotic stress. However, the mechanisms behind sub-MIC antibiotic-induced biofilm formation are unclear. We show that treatment of Pseudomonas aeruginosa with multiple classes of sub-MIC antibiotics with distinct targets induces biofilm formation. Further, addition of exogenous eDNA or cell lysate failed to increase biofilm formation to the same extent as antibiotics, suggesting that the release of cellular contents by antibiotic-driven bacteriolysis is insufficient. Using a genetic screen for stimulation-deficient mutants, we identified the outer membrane porin OprF and the ECF sigma factor SigX as important. Similarly, loss of OmpA – the Escherichia coli OprF homolog – prevented sub-MIC antibiotic stimulation of E. coli biofilms. Our screen also identified the periplasmic disulfide bond-forming enzyme DsbA and a predicted cyclic-di-GMP phosphodiesterase encoded by PA2200 as essential for biofilm stimulation. The phosphodiesterase activity of PA2200 is likely controlled by a disulfide bond in its regulatory domain, and folding of OprF is influenced by disulfide bond formation, connecting the mutant phenotypes. Addition of reducing agent dithiothreitol prevented sub-MIC antibiotic biofilm stimulation. Finally, activation of a c-di-GMP-responsive promoter follows treatment with sub-MIC antibiotics in the wild-type but not an oprF mutant. Together, these results show that antibiotic-induced biofilm formation is likely driven by a signaling pathway that translates changes in periplasmic redox state into elevated biofilm formation through increases in c-di-GMP.

No Money No Time (NMNT) is a culinary nutrition website designed to optimize diet quality. The primary aim was to evaluate the impact of an online targeted nutrition challenge email campaign that encouraged engagement with NMNT and goal setting to improve diet quality and weekly food expenditure. A secondary aim was to assess NMNT engagement. Australian adults ≥18 years were recruited to the eHealth nutrition challenge delivered via weekly emails. Diet quality was assessed using the Healthy Eating Quiz (HEQ) diet quality tool. Engagement was assessed using email open and click-through rates. Intention-to-treat (ITT) analysis was conducted using mixed effects linear regression. Of 481 adults (49.7 ± 13.9 years, 84% female) who enrolled 79 (16%) completed the challenge. ITT results indicated statistically significant 6-week increases in diet quality score (+3.8 points p ≤ 0.001, d = 0.58) with sub-scale improvements in vegetables (+0.9 points, p = 0.01, d = 0.32), fruit (+1.2 points, p ≤ 0.001, d = 0.55), and dairy (+0.9 points, p ≤ 0.001, d = 0.58). There were significant post-challenge reductions in household spending on takeaway/snacks/coffee of AUD 8.9 per week (p = 0.01, d = 0.29), body weight reduction (−0.6 kg, p = 0.03, d = 0.26), and BMI (−0.2 kg/m2p = 0.02, d = 0.28). The email open rate remained constant at around 67% (56% to 75%), with an average click-through rate of 18% (7.1% to 37.9%). The eHealth nutrition challenge significantly improved diet quality while reducing BMI and money spent on discretionary foods. Strategies to scale the challenge should be tested as an innovative population strategy for improving diet quality, health indicators, and managing household food budgets.

Abstract Background There is a lack of understanding of the potential utility of a chatbot integrated into a website to support healthy eating among young adults. Therefore, the aim was to interview key informants regarding potential utility and design of a chatbot to: (1) increase young adults’ return rates and engagement with a purpose-built healthy eating website and, (2) improve young adults’ diet quality. Methods Eighteen qualitative, semi-structured interviews were conducted across three stakeholder groups: (i) experts in dietary behaviour change in young adults (n = 6), (ii) young adult users of a healthy eating website (n = 7), and (iii) experts in chatbot design (n = 5). Interview questions were guided by a behaviour change framework and a template analysis was conducted using NVivo. Results Interviewees identified three potential roles of a chatbot for supporting healthy eating in young adults; R1: improving healthy eating knowledge and facilitating discovery, R2: reducing time barriers related to healthy eating, R3: providing support and social engagement. To support R1, the following features were suggested: F1: chatbot generated recommendations and F2: triage to website information or externally (e.g., another website) to address current user needs. For R2, suggested features included F3: nudge or behavioural prompts at critical moments and F4: assist users to navigate healthy eating websites. Finally, to support R3 interviewees recommended the following features: F5: enhance interactivity, F6: offer useful anonymous support, F7: facilitate user connection with content in meaningful ways and F8: outreach adjuncts to website (e.g., emails). Additional ‘general’ chatbot features included authenticity, personalisation and effective and strategic development, while the preferred chatbot style and language included tailoring (e.g., age and gender), with a positive and professional tone. Finally, the preferred chatbot message subjects included training (e.g., would you like to see a video to make this recipe?), enablement (e.g., healthy eating doesn’t need to be expensive, we’ve created a budget meal plan, want to see?) and education or informative approaches (e.g., “Did you know bananas are high in potassium which can aid in reducing blood pressure?”). Conclusion Findings can guide chatbot designers and nutrition behaviour change researchers on potential chatbot roles, features, style and language and messaging in order to support healthy eating knowledge and behaviours in young adults.

Exposure of Escherichia coli to sub-inhibitory antibiotics stimulates biofilm formation through poorly characterized mechanisms. Using a high-throughput Congo Red binding assay to report on biofilm matrix production, we screened ~4000 E. coli K12 deletion mutants for deficiencies in this biofilm stimulation response. We screened using three different antibiotics to identify core components of the biofilm stimulation response. Mutants lacking acnA, nuoE, or lpdA failed to respond to sub-MIC cefixime and novobiocin, implicating central metabolism and aerobic respiration in biofilm stimulation. These genes are members of the ArcA/B regulon-controlled by a respiration-sensitive two-component system. Mutants of arcA and arcB had a 'pre-activated' phenotype, where biofilm formation was already high relative to wild type in vehicle control conditions, and failed to increase further with the addition of sub-MIC cefixime. Using a tetrazolium dye and an in vivo NADH sensor, we showed spatial co-localization of increased metabolic activity with sub-lethal concentrations of the bactericidal antibiotics cefixime and novobiocin. Supporting a role for respiratory stress, the biofilm stimulation response to cefixime and novobiocin was inhibited when nitrate was provided as an alternative electron acceptor. Deletion of a gene encoding part of the machinery for respiring nitrate abolished its ameliorating effects, and nitrate respiration increased during growth with sub-MIC cefixime. Finally, in probing the generalizability of biofilm stimulation, we found that the stimulation response to translation inhibitors, unlike other antibiotic classes, was minimally affected by nitrate supplementation, suggesting that targeting the ribosome stimulates biofilm formation in distinct ways. By characterizing the biofilm stimulation response to sub-MIC antibiotics at a systems level, we identified multiple avenues for design of therapeutics that impair bacterial stress management.

Introduction Approximately 15%–20% of the adult population self-report symptoms of addictive eating. There are currently limited options for management. Motivational interviewing-based interventions, containing personalised coping skills training, have been found to be effective for behaviour change in addictive disorders (eg, alcohol). This project builds upon foundations of an addictive eating feasibility study previously conducted and co-design process involving consumers. The primary aim of this study is to examine the efficacy of a telehealth intervention targeting addictive eating symptoms in Australian adults compared with passive intervention and control groups.Methods and analysis This three-arm randomised controlled trial will recruit participants 18–85 years, endorsing ≥3 symptoms on the Yale Food Addiction Scale (YFAS) 2.0, with body mass index >18.5 kg/m2. Addictive eating symptoms are assessed at baseline (pre-intervention), 3 months (post-intervention) and 6 months. Other outcomes include dietary intake and quality, depression, anxiety, stress, quality of life, physical activity and sleep hygiene. Using a multicomponent clinician-led approach, the active intervention consists of five telehealth sessions (15–45 min each) delivered by a dietitian over 3 months. The intervention uses personalised feedback, skill-building exercises, reflective activities and goal setting. Participants are provided with a workbook and website access. The passive intervention group receives the intervention via a self-guided approach with access to the workbook and website (no telehealth). The control group receives personalised written dietary feedback at baseline and participants advised to follow their usual dietary pattern for 6 months. The control group will be offered the passive intervention after 6 months. The primary endpoint is YFAS symptom scores at 3 months. A cost–consequence analysis will determine intervention costs alongside mean change outcomes.Ethics and dissemination Human Research Ethics Committee of University of Newcastle, Australia provided approval (H-2021-0100). Findings will be disseminated via publication in peer-reviewed journals, conference presentations, community presentations and student theses.Trial registration number Australia New Zealand Clinical Trials Registry (ACTRN12621001079831).

ABSTRACT Iron is essential for many biological functions in bacteria, but its poor solubility is a limiting factor for growth. Bacteria produce siderophores, soluble natural products that bind iron with high affinity, to overcome this challenge. Siderophore-iron complexes return to the cell through specific outer membrane transporters. The opportunistic pathogen Pseudomonas aeruginosa makes multiple transporters that recognize its own siderophores, pyoverdine and pyochelin, and xenosiderophores produced by other bacteria or fungi, which gives it a competitive advantage. Some antibiotics exploit these transporters to bypass the membrane to reach their intracellular targets—including the thiopeptide antibiotic, thiostrepton (TS), which uses the pyoverdine transporters FpvA and FpvB to cross the outer membrane. Here, we assessed TS susceptibility in the presence of various siderophores and discovered that ferrichrome and ferrioxamine B antagonized TS uptake via FpvB. Unexpectedly, we found that FpvB transports ferrichrome and ferrioxamine B with higher affinity than pyoverdine. Site-directed mutagenesis of FpvB coupled with competitive growth inhibition and affinity label quenching studies suggested that the siderophores and antibiotic share a binding site in an aromatic pocket formed by the plug and barrel domains but have differences in their binding mechanism and molecular determinants for uptake. This work describes an alternative uptake pathway for ferrichrome and ferrioxamine B in P. aeruginosa and emphasizes the promiscuity of siderophore transporters, with implications for Gram-negative antibiotic development via the Trojan horse approach. IMPORTANCE Gram-negative bacteria express a variety of outer membrane transporters to import critical nutrients such as iron. Due to its insolubility, iron is taken up while bound to small-molecule chelators called siderophores. Pseudomonas aeruginosa takes up its own siderophores pyoverdine and pyochelin but can also steal siderophores produced by other bacteria and fungi, giving it a competitive advantage in iron-limited environments. Here, we used whole-cell reporter assays to show that FpvB, originally identified as a secondary transporter for pyoverdine, transports the chemically distinct fungal siderophore ferrichrome and the bacterial siderophore ferrioxamine B with high affinity. FpvB is also used by thiopeptide antibiotic thiostrepton for uptake. We predicted that all of these ligands bind to a common hydrophobic pocket in FpvB and used site-directed mutagenesis coupled with phenotypic assays to identify residues required for uptake. These analyses showed that siderophore and antibiotic uptake could be uncoupled. Our data show that FpvB is a promiscuous transporter of multiple chemically distinct ligands and fills in missing details of ferrichrome transport by P. aeruginosa. A clearer picture of the spectrum of outer membrane transporter substrate specificity is useful for the design of novel siderophore-antibiotic conjugates that can exploit nutrient uptake pathways to kill challenging Gram-negative pathogens.

Objective: Although parenting responsibilities are correlated with gender disparities in professional development and salary, the nature of parental challenges is not well characterized. The aims of this study were to (1) illuminate faculty physicians' experiences with parenting and (2) identify system challenges and opportunities for improvement. Materials and Methods: In October 2019, a survey about parenting was sent to all physician faculty at a large Midwest academic medical center. Qualitative analysis of free-text response to the survey item ?is there anything you wish to share about your experience of pregnancy or parenting as a physician? was performed. Themes were inductively identified and developed from the responses in a team-based iterative approach. Results: Of 2069 total physician faculty, 1085 (52.4%) responded to the survey and 253 (23%) of the respondents provided free-text comments. From these comments, the authors identified three themes as sources of challenges for physician parents: operational constraints, gender biases, and nontraditional or nonheteronormative family structures. Operational factors pertained to lack of scheduling flexibility, childcare challenges, lactation, colleague coverage, and transparency of policies. Responses indicated that gender biases are encountered by all genders, and expectations built on assumptions of ?traditional? gender roles and family structure are problematic for many physician parents. Conclusion: Addressing the challenges and opportunities identified in the study is critical to building a more supportive institutional culture around parenting and to increase gender parity in academic medicine.

Research into the complexities of addictive eating behaviours continues to develop, as a deeper understanding of this construct beyond self-report diagnostic tools emerges. In this study, we undertook structured interviews with 40 participants engaged in a personality-based management program for addictive eating, to gain insight into what situations lead people with addictive eating behaviours to overeat, and how they believe their lives would be different if they had control over their eating. A phenomenological analysis to explore compulsion and control in the context of food experiences for participants was used to construct two main themes of the addictive eating paradox and striving to transition from ‘other’ to ‘normal’. The addictive eating paradox identified multiple contradictory experiences of a situation, e.g., ‘loving food’ but ‘hating food’. Striving to transition from ‘other’ to ‘normal’ encompassed the idea that participants envisaged that by gaining control over their eating they could become ‘normal’. This study emphasises the need to provide support and strategies to help people navigate paradoxical thoughts and presents new ideas to increase the effectiveness of interventions for individuals struggling with the complex self-beliefs held by those with addictive eating behaviours.

IntroductionMany university students have poor mental health, and co-occurring health risk behaviors. Targeting health behavior change in this population may improve mental health outcomes. This scoping review describes the extent and range of randomized controlled trials (RCT) evaluating interventions targeting health risk behaviors and measuring a mental health outcome, among university students.MethodsSix electronic databases were searched for RCTs published until the 18th May 2021. Eligible RCTs included university students, evaluated interventions that promoted health behavior change (i.e., dietary intake, physical activity, sedentary behavior, alcohol and drug use, smoking, and sleep), and measured a mental health-related outcome.ResultsFifty-nine RCTs met the inclusion criteria that were published from 2000 to 2021, and over half (n = 33) were conducted in the United States. Interventions evaluated within the RCTs (n = 92) predominantly targeted changes to dietary intake (n = 41 interventions), physical activity (n = 39), or alcohol intake (n = 35). Most interventions targeted one (n = 51) or two (n = 27) health behaviors only. Included RCTs considered mental ill health outcomes (n = 24), psychological wellbeing outcomes (n = 20), or both (n = 15).DiscussionThis scoping review identified a moderate volume of experimental research investigating the impact of health behavior interventions on university students' mental health. There is scope for further research examining health behavior interventions targeting university students, particularly interventions taking a multi-behavioral approach.

Abstract Background To describe a-priori diet quality indices used in children and adolescents, appraise the validity and reliability of these indices, and synthesise evidence on the relationship between diet quality and physical and mental health, and growth-related outcomes. Methods Five electronic databases were searched until January 2019. An a-priori diet quality index was included if it applied a scoring structure to rate child or adolescent (aged 0–18-years) dietary intakes relative to dietary or nutrient guidelines. Diagnostic accuracy studies and prospective cohort studies reporting health outcomes were appraised using the Academy of Nutrition and Dietetics Quality Criteria Checklist. Results From 15,577 records screened, 128 unique paediatric diet quality indices were identified from 33 countries. Half of the indices’ scores rated both food and nutrient intakes (n = 65 indices). Some indices were age specific: infant (

Bacterial type IV pilus-like systems catalyse the formation of pilin fibres but it is unknown how they are powered. Here, the authors present crystal and cryo-EM structures of the hexameric motor ATPases PilB and PilT from Type IVa Pilus that reveal different conformational states, classify the conformations of all PilT-like ATPase structures and propose a model for PilT function.

With the growing popularity of touchscreen cognitive testing in rodents, it is imperative to understand the fundamental effects exposure to this paradigm can have on the animals involved. In this study, we set out to assess hippocampal-dependant learning in the APP/PS1 mouse model of Alzheimer’s disease (AD) on two highly translatable touchscreen tasks – the Paired Associate Learning (PAL) task and the Trial Unique Non-Matching to Location (TUNL) task. Both of these tests are based on human tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and are sensitive to deficits in both mild cognitive impairment (MCI) and AD. Mice were assessed for deficits in PAL at 9–12 months of age, then on TUNL at 8–11 and 13–16 months. No cognitive deficits were evident in APP/PS1 mice at any age, contrary to previous reports using maze-based learning and memory tasks. We hypothesized that daily and long-term touchscreen training may have inadvertently acted as a cognitive enhancer. When touchscreen-tested mice were assessed on the Morris water maze, they showed improved task acquisition compared to naïve APP/PS1 mice and wild-type (WT) littermate controls. In addition, we show that touchscreen-trained WT and APP/PS1 mice show increased cell proliferation and immature neuron numbers in the dentate gyrus compared to behaviorally naïve WT and APP/PS1 mice. This result indicates that the touchscreen testing paradigm could improve cognitive performance, and/or mask an impairment, in experimental mouse models. This touchscreen-induced cognitive enhancement may involve increased neurogenesis, and possibly other forms of cellular plasticity. This is the first study to show increased numbers of proliferating cells and immature neurons in the hippocampus following touchscreen testing, and that touchscreen training can improve cognitive performance in maze-based spatial navigation tasks. This potential for touchscreen testing to induce cognitive enhancement, or other phenotypic shifts, in preclinical models should be considered in study design. Furthermore, touchscreen-mediated cognitive enhancement could have therapeutic implications for cognitive disorders.

Adolescence is considered an important period of neurodevelopment. It is a time for the emergence of psychosocial vulnerabilities, including symptoms of depression, eating disorders, and increased engagement in unhealthy eating behaviours. Food addiction (FA) in adolescents is an area of study where there has been substantial growth. However, to date, limited studies have considered what demographic characteristics of adolescents may predispose them to endorse greater symptoms of FA. Studies have found a variety of factors that often cluster with and may influence an adolescent’s eating behaviour such as sleep, level of self-control, and parenting practices, as well as bullying. Therefore, this study investigated a range of socio-demographic, trait, mental health, and lifestyle-related profiles (including self-control, parenting, bullying, and sleep) as proximal factors associated with symptoms of FA, as assessed via the Yale Food Addiction Scale for Children (YFAS-C) in a large sample of Australian adolescents. Following data cleaning, the final analysed sample included 6587 students (age 12.9 years ± 0.39; range 10.9–14.9 years), with 50.05% identifying as male (n = 3297), 48.5% as female (n = 3195), 1.02% prefer not to say (n = 67), and 0.43% as non-binary (n = 28). Self-control was found to be the most significant predictor of total FA symptom score, followed by female gender, sleep quality, and being a victim of bullying. Universal prevention programs should therefore aim to address these factors to help reduce the prevalence or severity of FA symptoms within early adolescent populations.

(1) Background: School professionals such as teachers and counsellors are uniquely positioned to facilitate discussion around disordered eating and body image; however, little is known about the needs of school professionals with respect to eating disorder prevention. This study aimed to explore the needs and perceptions of Australian school professionals regarding eating disorder prevention. (2) Methods: School professionals were recruited to a mixed-methods online cross-sectional survey. The survey assessed demographics and perceived needs and attitudes to eating disorder prevention. (3) Results: Most participants (92%) were willing to participate in eating disorder prevention; however, only 61% reported good knowledge and 41% reported feeling confident in implementing eating disorder prevention. Those who had received training in eating disorders (24%) reported higher confidence (p = 0.02) and knowledge (p = 0.04). Only 66% of respondents reported that all teachers should be involved in eating disorder prevention while barriers including workload, knowledge, and resources were commonly highlighted. Fewer respondents working in primary school settings reported the need for prevention approaches (p = 0.046). (4) Conclusions: Despite a willingness to be involved in the prevention of eating disorders, there are inconsistencies in attitudes regarding the role of school professionals in eating disorder prevention. The findings of this study reinforce that understanding professional roles, school settings, and personal attitudes is critical in the development of more efficacious school professional training and prevention interventions.

The prodromal phase of Parkinson’s disease (PD) is characterised by many non-motor symptoms, and these have recently been posited to be predictive of later diagnosis. Genetic rodent models can develop non-motor phenotypes, providing tools to identify mechanisms underlying the early development of PD. However, it is not yet clear how reproducible non-motor phenotypes are amongst genetic PD rodent models, whether phenotypes are age-dependent, and the translatability of these phenotypes has yet to be explored. A systematic literature search was conducted on studies using genetic PD rodent models to investigate non-motor phenotypes; cognition, anxiety/depressive-like behaviour, gastrointestinal (GI) function, olfaction, circadian rhythm, cardiovascular and urinary function. In total, 51 genetic models of PD across 150 studies were identified. We found outcomes of most phenotypes were inconclusive due to inadequate studies, assessment at different ages, or variation in experimental and environmental factors. GI dysfunction was the most reproducible phenotype across all genetic rodent models. The mouse model harbouring mutant A53T, and the wild-type hα-syn overexpression (OE) model recapitulated the majority of phenotypes, albeit did not reliably produce concurrent motor deficits and nigral cell loss. Furthermore, animal models displayed different phenotypic profiles, reflecting the distinct genetic risk factors and heterogeneity of disease mechanisms. Currently, the inconsistent phenotypes within rodent models pose a challenge in the translatability and usefulness for further biomechanistic investigations. This review highlights opportunities to improve phenotype reproducibility with an emphasis on phenotypic assay choice and robust experimental design.

Purpose: Quantitative susceptibility mapping (QSM) is a novel MR technique that allows mapping of tissue susceptibility values from MR phase images. QSM is an ill-conditioned inverse problem, and although several methods have been proposed in the field, in the presence of a wide range of susceptibility sources, streaking artifacts appear around high susceptibility regions and contaminate the whole QSM map. QSMART is a post-processing pipeline that uses two-stage parallel inversion to reduce the streaking artifacts and remove banding artifact at the cortical surface and around the vasculature. Method: Tissue and vein susceptibility values were separately estimated by generating a mask of vasculature driven from the magnitude data using a Frangi filter. Spatially dependent filtering was used for the background field removal step and the two susceptibility estimates were combined in the final QSM map. QSMART was compared to RESHARP/iLSQR and V-SHARP/iLSQR inversion in a numerical phantom, 7T in vivo single and multiple-orientation scans, 9.4T ex vivo mouse data, and 4.7T in vivo rat brain with induced focal ischemia. Results: Spatially dependent filtering showed better suppression of phase artifacts near cortex compared to RESHARP and V-SHARP, while preserving voxels located within regions of interest without brain edge erosion. QSMART showed successful reduction of streaking artifacts as well as improved contrast between different brain tissues compared to the QSM maps obtained by RESHARP/iLSQR and V-SHARP/iLSQR. Conclusion: QSMART can reduce QSM artifacts to enable more robust estimation of susceptibility values in vivo and ex vivo.

Schizophrenia (SZ) is a psychiatric disorder that constitutes one of the top 10 global causes of disability. More recently, a potential pathogenic role for the gut microbial community (microbiota) has been highlighted, with numerous studies describing dysregulated microbial profiles in SZ patients when compared to healthy controls. However, no animal model of SZ has previously recapitulated the gut dysbiosis observed clinically. Since the metabotropic glutamate receptor 5 (mGlu5) knockout mice provide a preclinical model of SZ with strong face and predictive validity, in the present study we performed gut microbiome profiling of mGlu5 knockout (KO) and wild-type (WT) mice by 16S rRNA sequencing of bacterial genomic DNA from fecal samples, analyzing bacterial diversity and taxonomic composition, as well as gastrointestinal parameters as indicators of gut function. We found a significant genotype difference in microbial beta diversity. Analysis of composition of microbiomes (ANCOM) models were performed to evaluate microbiota compositions, which identified a decreased relative abundance of the Erysipelotrichaceae family and Allobaculum genus in this mouse model of SZ. We also identified a signature of bacteria discriminating between the genotypes (KO and WT), consisting of the Erysipelotrichales, Bacteroidales, and Clostridiales orders and macroscopic gut differences. We thus uncovered global differential community composition in the gut microbiota profile between mGlu5 KO and WT mice, outlining the first evidence for gut dysbiosis in a genetic animal model of SZ. Our findings suggest that this widely used preclinical model of SZ also has substantial utility for investigations of gut dysbiosis and associated signaling via the microbiota–gut–brain axis, as potential modulators of SZ pathogenesis. Our discovery opens up new avenues to explore gut dysbiosis and its proposed links to brain dysfunction in SZ, as well as novel therapeutic approaches to this devastating disorder.

BACKGROUND:The ability to predict risk allows healthcare providers to propose which patients might benefit most from certain therapies, and is relevant to payers' demands to justify clinical and economic value. To understand the robustness of risk prediction models for heart failure (HF), we conducted a systematic literature review to (1) identify HF risk-prediction models, (2) assess statistical approach and extent of validation, (3) identify common variables, and (4) assess risk of bias (ROB). METHODS:Literature databases were searched from March 2013 to May 2018 to identify risk prediction models conducted in an out-of-hospital setting in adults with HF. Distinct risk prediction variables were ranked according to outcomes assessed and incorporation into the studies. ROB was assessed using Prediction model Risk Of Bias ASsessment Tool (PROBAST). RESULTS:Of 4720 non-duplicated citations, 40 risk-prediction publications were deemed relevant. Within the 40 publications, 58 models assessed 55 (co)primary outcomes, including all-cause mortality (n = 17), cardiovascular death (n = 9), HF hospitalizations (n = 15), and composite endpoints (n = 14). Few publications reported detail on handling missing data (n = 11; 28%). The discriminatory ability for predicting all-cause mortality, cardiovascular death, and composite endpoints was generally better than for HF hospitalization. 105 distinct predictor variables were identified. Predictors included in >5 publications were: N-terminal prohormone brain-natriuretic peptide, creatinine, blood urea nitrogen, systolic blood pressure, sodium, NYHA class, left ventricular ejection fraction, heart rate, and characteristics including male sex, diabetes, age, and BMI. Only 11/58 (19%) models had overall low ROB, based on our application of PROBAST. In total, 26/58 (45%) models discussed internal validation, and 14/58 (24%) external validation. CONCLUSIONS:The majority of the 58 identified risk-prediction models for HF present particular concerns according to ROB assessment, mainly due to lack of validation and calibration. The potential utility of novel approaches such as machine learning tools is yet to be determined. REGISTRATION NUMBER:The SLR was registered in Prospero (ID: CRD42018100709).

[This corrects the article DOI: 10.1371/journal.pone.0224135.].

Due to global advances in technology, image-based food record methods have emerged as an alternative to traditional assessment methods. The use of image-based food records in low and lower-middle income countries such as Tanzania is limited, with countries still using traditional methods. The current study aimed to determine the feasibility of using a new voice and image-based dietary assessment system (VISIDA) in Dar es Salaam, Tanzania. This mixed-method study recruited 18 nutritionists as participants who collected image-based records of food and drinks they consumed using the VISIDA smartphone app. Participants viewed an online demonstration of the VISIDA web platform and the analysis process for intake data collected using the VISIDA app. Then, participants completed an online survey and were interviewed about the VISIDA app and web platform for food and nutrient intake analysis. The method was reported as being acceptable and was found to be easy to use, although technical challenges were experienced by some participants. Most participants indicated a willingness to use the VISIDA app again for one week or longer and were interested in using the VISIDA system in their current role. Participants acknowledged that the VISIDA web platform would simplify some aspects of their current job. Image-based food records could potentially be used in Tanzania to improve the assessment of dietary intake by nutritionists in urban areas. Participants recommended adding sound-on notifications, using the VISIDA app in both Apple and Android phones, enabling installation from the app store, and improving the quality of the fiducial markers.

Accuracy in quantifying energy intake (EI) using common dietary assessment methods is crucial for interpreting the relationship between diet and chronic disease. The aim of this systematic review was to evaluate the validity of dietary assessment methods used to estimate the EI of adults in comparison to total energy expenditure (TEE) measured by doubly labeled water (DLW). Articles in English across nine electronic databases, published between 1973 and February 2019 were retrieved. Studies were included if participants were adults (≥18 years) and used the DLW technique to measure TEE compared to self-reported EI. A total of 59 studies were included, with a total of 6,298 free living adults and a mean of 107 participants per study. The majority of studies including 16 studies that included a technology based method reported significant (P < 0.05) under-reporting of EI when compared to TEE, with few over-reporting EI. Misreporting was more frequent among females compared to males within recall based dietary assessment methods. The degree of under-reporting was highly variable within studies using the same method, with 24 h recalls having less variation and degree of under-reporting compared to other methods.

This three-arm randomised controlled trial evaluated whether (1) a multi-component weight loss intervention targeting diet, physical activity (PA), and sleep was effective at improving dietary intake over six months and 12 months, compared with a control, and (2) the enhanced diet, PA, and sleep intervention was more effective at improving dietary intake than the traditional diet and PA intervention. A total of 116 adults (70% female, 44.5 years, BMI 31.7 kg/m2) were randomised to either traditional diet and PA intervention; enhanced diet, PA, and sleep intervention; or wait-list control. To examine between-group differences, intervention groups were pooled and compared with the control. Then, the two intervention groups were compared. At six months, the pooled intervention group consumed 1011 fewer kilojoules/day (95% CI −1922, −101), less sodium (−313.2 mg/day; 95% CI −591.3, −35.0), and higher %EI from fruit (+2.1%EI; 95% CI 0.1, 4.1) than the controls. There were no differences in intake between the enhanced and traditional groups at six months. At 12 months, the pooled intervention and control groups reported no significant differences. However, compared to the traditional group, the enhanced reported higher %EI from nutrient-dense foods (+7.4%EI; 95% CI 1.3, 13.5) and protein (+2.4%EI; 95% CI 0.1, 4.6), and reduced %EI from fried/takeaway foods (−3.6%EI; 95% CI −6.5, −0.7), baked sweet products (−2.0%EI; 95% CI −3.6, −0.4), and packaged snacks (−1.1%EI; 95% CI −2.2, −0.3). This weight loss intervention reduced total energy and sodium intakes as well as increased fruit intake in adults at six months. The enhanced intervention group reported improved dietary intake relative to the traditional group at 12 months.

Research on the concept of food addiction (FA) has steadily grown and, based on a widely used self-report, FA is estimated to affect between 16–20% of the adult population. However, there are few interventions available for people with self-reported FA, and their efficacy is unclear. The primary aim of the review was to examine the efficacy of different interventions, including behavioural/lifestyle, medication and surgical approaches, for reducing symptoms and/or changing diagnosis of FA among adolescents and adults. A secondary aim was to examine the influence of sex as a moderator of intervention effects. A systematic search was performed from 2008–2020 to identify studies that used the YFAS to assess the effectiveness of interventions on FA. Nine studies were identified (n = 7 adults, n = 2 adolescents) including a total of 812 participants (range 22–256) with an average of 69% females per study. The types of interventions included medications (n = 3), lifestyle modification (n = 3), surgical (n = 2) and behavioural (n = 1), with FA being assessed as a secondary outcome in all studies. Five studies in adults reported a significant reduction in FA symptoms or diagnosis from pre to post-intervention, two when compared to a control group and three in the intervention group only. Efficacious interventions included: medication (combination of naltrexone and bupropion, as well as pexacerfont), bariatric surgery and lifestyle modification. No significant changes in FA were reported in adolescent studies. Given few studies were identified by the review, there is insufficient evidence to provide clear recommendations for practice; however, some interventions show potential for reducing self-reported FA outcomes in adults. Future research should explore the longer-term efficacy of interventions and the effectiveness of treatments with sufficient sample sizes.

Bacterial type IVa pili are protein filaments used for motility and protein secretion. Here the authors present crystal structures of theGeobacter metallireducensPilB ATPase in two nucleotide states, and suggest a clockwise rotation of the central sub-pores of PilB that would support the assembly of a right-handed helical pilus.

Background: The study evaluates a group of Military Service Members specialized in blast explosive training called “Breachers” who are routinely exposed to multiple low-level blasts while teaching breaching at the U.S. Marine Corps in Quantico Virginia. The objective of this study was to determine if there are any acute or long-term auditory changes due to repeated low-level blast exposures used in training. The performance of the instructor group “Breachers” was compared to a control group, “Engineers”. Methods: A total of 11 Breachers and four engineers were evaluated in the study. The participants received comprehensive auditory tests, including pure-tone testing, speech-in-noise (SIN) measures, and central auditory behavioral and objective tests using early and late (P300) auditory evoked potentials over a period of 17 months. They also received shorter assessments immediately following the blast-exposure onsite at Quantico. Results: No acute or longitudinal effects were identified. However, there were some interesting baseline effects found in both groups. Contrary to the expected, the onsite hearing thresholds and distortion product otoacoustic emissions were slightly better at a few frequencies immediately after blast-exposure than measurements obtained with the same equipment weeks to months after each blast-exposure. Conclusions: To date, the current study is the most comprehensive study that evaluates the long-term effects of blast-exposure on hearing. Despite extensive testing to assess changes, the findings of this study suggest that the levels of current exposures used in this military training environment do not seem to have an obvious deleterious effect on hearing.

Background: It has been suggested that addictive behaviors related to consumption of specific foods could contribute to overeating and obesity. Although energy-dense, hyper-palatable foods are hypothesized to be associated with addictive-like eating behaviors, few studies have assessed this in humans. Objective: To evaluate in young adults whether intakes of specific foods are associated with ‘food addiction’, as assessed by the Yale Food Addiction Scale (YFAS), and to describe the associated nutrient intake profiles. Design: Australian adults aged 18–35 years were invited to complete an online cross-sectional survey including demographics, the YFAS and usual dietary intake. Participants were classified as food addicted (FAD) or non-addicted (NFA) according to the YFAS predefined scoring criteria. Results: A total 462 participants (86% female, 73% normal weight) completed the survey, with 14.7% (n = 68) classified as FAD. The FAD group had a higher proportion of females (p = .01) and higher body mass index (p

Targeting kinases linked to insulin resistance (IR) and inflammation may help in reducing the risk of type 2 diabetes (T2D) and Alzheimer’s disease (AD) in its early stages. This study aimed to determine whether DHA-rich fish oil supplementation reduces glycogen synthase kinase (GSK-3), which is linked to both IR and AD. Baseline and post-intervention plasma samples from 58 adults with abdominal obesity (Age: 51.7 ± 1.7 years, BMI: 31.9 ± 0.8 kg/m2) were analysed for outcome measures. Participants were allocated to 2 g DHA-rich fish oil capsules (860 mg DHA + 120 mg EPA) (n = 31) or placebo capsules (n = 27) per day for 12 weeks. Compared to placebo, DHA-rich fish oil significantly reduced GSK-3β by −2.3 ± 0.3 ng/mL. An inverse correlation (p < 0.05) was found between baseline insulin and IR and their changes following intervention only in participants with C-reactive protein levels higher than 2.4 mg/L. DHA-rich fish oil reduces GSK-3 and IR, suggesting a potential role of long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) in ameliorating AD risk.

Dietary supplementation with curcumin has been previously reported to have beneficial effects in people with insulin resistance, type 2 diabetes (T2D) and Alzheimer’s disease (AD). This study investigated the effects of dietary supplementation with curcumin on key peptides implicated in insulin resistance in individuals with high risk of developing T2D. Plasma samples from participants recruited for a randomised controlled trial with curcumin (180 mg/day) for 12 weeks were analysed for circulating glycogen synthase kinase-3 β (GSK-3β) and islet amyloid polypeptide (IAPP). Outcome measures were determined using ELISA kits. The homeostasis model for assessment of insulin resistance (HOMA-IR) was measured as parameters of glycaemic control. Curcumin supplementation significantly reduced circulating GSK-3β (−2.4 ± 0.4 ng/mL vs. −0.3 ± 0.6, p = 0.0068) and IAPP (−2.0 ± 0.7 ng/mL vs. 0.4 ± 0.6, p = 0.0163) levels compared with the placebo group. Curcumin supplementation significantly reduced insulin resistance (−0.3 ± 0.1 vs. 0.01 ± 0.05, p = 0.0142) compared with placebo group. Dietary supplementation with curcumin reduced circulating levels of IAPP and GSK-3β, thus suggesting a novel mechanism through which curcumin could potentially be used for alleviating insulin resistance related markers for reducing the risk of T2D and AD.

Optimal dietary intake is important for the health and physical performance of military personnel. For military veterans, the complex nature of transition into civilian life and sub-optimal dietary intake is a leading contributor to the increased burden of disease. A scoping review was undertaken to determine what is known about the assessment and reporting of dietary intakes within both military and veteran populations. In addition, this review determines if studies reporting on the dietary intake of military personnel or veterans include comparisons with dietary guidelines. Six databases were searched to identify papers published from the database inception to April 2019. Observational and intervention studies were searched to identify if they assessed and reported whole dietary intake data, reported data exclusively for a military or veteran population, and included only healthy populations. A total of 89 studies were included. The majority of studies used one dietary assessment method (n = 76, 85%) with fewer using multiple methods (n = 13, 15%). The most frequent methodology used was food frequency questionnaires (FFQ) (n = 40, 45%) followed by 24-hour recalls (n = 8, 9%) and food records (n = 8, 9%). The main dietary outcomes reported were macronutrients: carbohydrate, protein, fat, and alcohol (n = 66, 74%) with total energy intake reported in n = 59 (66%). Fifty four (61%) studies reported a comparison with country-specific dietary guidelines and 14 (16%) reported a comparison with the country-specific military guidelines. In conclusion, dietary intake in military settings is most commonly assessed via FFQs and 24-hour recalls. Dietary intake reporting is mainly focused around intakes of energy and macronutrients. Most studies compare against dietary guidelines, however, comparison to specific military dietary guidelines is minimal.

ABSTRACT Motility is an important virulence trait for many bacterial pathogens, allowing them to position themselves in appropriate locations at appropriate times. The motility structures type IV pili and flagella are also involved in sensing surface contact, which modulates pathogenicity. In Pseudomonas aeruginosa, the PilS-PilR two-component system (TCS) regulates expression of the type IV pilus (T4P) major subunit PilA, while biosynthesis of the single polar flagellum is regulated by a hierarchical system that includes the FleSR TCS. Previous studies of Geobacter sulfurreducens and Dichelobacter nodosus implicated PilR in regulation of non-T4P-related genes, including some involved in flagellar biosynthesis. Here we used transcriptome sequencing (RNA-seq) analysis to identify genes in addition to pilA with changes in expression in the absence of pilR. Among the genes identified were 10 genes whose transcription increased in the pilA mutant but decreased in the pilR mutant, despite both mutants lacking T4P and pilus-related phenotypes. The products of these inversely dysregulated genes, many of which were hypothetical, may be important for virulence and surface-associated behaviors, as mutants had altered swarming motility, biofilm formation, type VI secretion system expression, and pathogenicity in a nematode model. Further, the PilSR TCS positively regulated transcription of fleSR, and thus many genes in the FleSR regulon. As a result, pilSR deletion mutants had defects in swimming motility that were independent of the loss of PilA. Together, these data suggest that in addition to controlling T4P expression, PilSR could have a broader role in the regulation of P. aeruginosa motility and surface sensing behaviors. IMPORTANCE Surface appendages such as type IV pili and flagella are important for establishing surface attachment and infection in a host in response to appropriate cues. The PilSR regulatory system that controls type IV pilus expression in Pseudomonas aeruginosa has an established role in expression of the major pilin PilA. Here we provide evidence supporting a new role for PilSR in regulating flagellum-dependent swimming motility in addition to pilus-dependent twitching motility. Further, even though both pilA and pilR mutants lack PilA and pili, we identified sets of genes downregulated in the pilR mutant and upregulated in a pilA mutant as well as genes downregulated only in a pilR mutant, independent of pilus expression. This finding suggests that change in the inner membrane levels of PilA is only one of the cues to which PilR responds to modulate gene expression. Identification of PilR as a regulator of multiple motility pathways may make it an interesting therapeutic target for antivirulence compounds.

One in five Australian pre-schoolers are overweight or obese, meaning the first years of life are vital for obesity primary prevention. Parent child feeding practices impact on children’s dietary intake, which in turn impacts on their weight status. Parents’ child feeding beliefs are heavily influenced by parenting peers. The aim of this cohort study is to evaluate the impact of the Parents in Child Nutrition Informing Community (PICNIC) study on parents feeding practices and diet quality. The secondary outcomes are the perceptions of trained peer educators and education recipients based on their involvement in PICNIC. One hundred parents with a child aged 0−2 years at time of recruitment will participate in peer educator training, then disseminate nutrition and child feeding content to other parents over an intervention period of 12 months, supported by project-specific, evidence-based social media pages and website. An additional 100 new parents, recruited by peer educators, will participate in the study as nutrition education recipients. Both peer educators and education recipients will complete quantitative child feeding surveys before and during the 12 month intervention and a dietary intake survey at a time point 12 months post intervention. Following the intervention, 30 education recipients will be asked to participate in semi-structured phone interviews about their experiences with PICNIC. Peer educators will contribute as co-researchers and active participants in the evolution of the PICNIC model. This study will contribute to enhanced understanding of contemporary health literacy strategies for communicating nutrition and feeding messages to new parents and the impact of these strategies on parents feeding practices and children’s dietary intake in a community setting.

Type IV pili (T4P) are surface-exposed protein fibers that play key roles in the bacterial life cycle via surface attachment/adhesion, biofilm formation, motility, and development. The order Myxococcales (myxobacteria) are members of the class Deltaproteobacteria and known for their large genome size and complex social behaviors, including gliding motility, fruiting body formation, biofilm production, and prey hunting. Myxococcus xanthus, the best-characterized member of the order, relies on the appropriate expression of 17 type IVa (T4aP) genes organized in a single cluster plus additional genes (distributed throughout the genome) for social motility and development. Here, we compared T4aP genes organization within the myxobacteria to understand their evolutionary origins and diversity. We found that T4aP genes are organized as large clusters in suborder Cystobacterineae, whereas in other two suborders Sorangiineae and Nannocystineae, these genes are dispersed throughout the genome. Based on the genomic organization, the phylogeny of conserved proteins, and synteny studies among 28 myxobacterial and 66 Proteobacterial genomes, we propose an evolutionary model for the origin of myxobacterial T4aP genes independently from other orders in class Deltaproteobacteria. Considering a major role for T4P, this study further proposes the origins and evolution of social motility in myxobacteria and provides a foundation for understanding how complex-behavioral traits, such as gliding motility, multicellular development, etc., might have evolved in this diverse group of complex organisms.

Type IV pili are expressed by a wide range of prokaryotes, including the opportunistic pathogen Pseudomonas aeruginosa. These flexible fibres mediate twitching motility, biofilm maturation, surface adhesion, and virulence. The pilus is composed mainly of major pilin subunits while the low abundance minor pilins FimU-PilVWXE and the putative adhesin PilY1 prime pilus assembly and are proposed to form the pilus tip. The minor pilins and PilY1 are encoded in an operon that is positively regulated by the FimS-AlgR two-component system. Independent of pilus assembly, PilY1 was proposed to be a mechanosensory component that-in conjunction with minor pilins-triggers up-regulation of acute virulence phenotypes upon surface attachment. Here, we investigated the link between the minor pilins/PilY1 and virulence. pilW, pilX, and pilY1 mutants had reduced virulence towards Caenorhabditis elegans relative to wild type or a major pilin mutant, implying a role in pathogenicity that is independent of pilus assembly. We hypothesized that loss of specific minor pilins relieves feedback inhibition on FimS-AlgR, increasing transcription of the AlgR regulon and delaying C. elegans killing. Reporter assays confirmed that FimS-AlgR were required for increased expression of the minor pilin operon upon loss of select minor pilins. Overexpression of AlgR or its hyperactivation via a phosphomimetic mutation reduced virulence, and the virulence defects of pilW, pilX, and pilY1 mutants required FimS-AlgR expression and activation. We propose that PilY1 and the minor pilins inhibit their own expression, and that loss of these proteins leads to FimS-mediated activation of AlgR that suppresses expression of acute-phase virulence factors and delays killing. This mechanism could contribute to adaptation of P. aeruginosa in chronic lung infections, as mutations in the minor pilin operon result in the loss of piliation and increased expression of AlgR-dependent virulence factors-such as alginate-that are characteristic of such infections.