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There is a wealth of literature on the observed association between childhood trauma and psychotic illness. However, the relationship between childhood trauma and psychosis is complex and could be explained, in part, by gene–environment correlation.
The association between schizophrenia polygenic scores (PGS) and experiencing childhood trauma was investigated using data from the Avon Longitudinal Study of Parents and Children (ALSPAC) and the Norwegian Mother, Father and Child Cohort Study (MoBa). Schizophrenia PGS were derived in each cohort for children, mothers, and fathers where genetic data were available. Measures of trauma exposure were derived based on data collected throughout childhood and adolescence (0–17 years; ALSPAC) and at age 8 years (MoBa).
Within ALSPAC, we found a positive association between schizophrenia PGS and exposure to trauma across childhood and adolescence; effect sizes were consistent for both child or maternal PGS. We found evidence of an association between the schizophrenia PGS and the majority of trauma subtypes investigated, with the exception of bullying. These results were comparable with those of MoBa. Within ALSPAC, genetic liability to a range of additional psychiatric traits was also associated with a greater trauma exposure.
Results from two international birth cohorts indicate that genetic liability for a range of psychiatric traits is associated with experiencing childhood trauma. Genome-wide association study of psychiatric phenotypes may also reflect risk factors for these phenotypes. Our findings also suggest that youth at higher genetic risk might require greater resources/support to ensure they grow-up in a healthy environment.
To understand price incentives to upsize combination meals at fast-food restaurants by comparing the calories (i.e. kilocalories; 1 kcal = 4·184 kJ) per dollar of default combination meals (as advertised on the menu) with a higher-calorie version (created using realistic consumer additions and portion-size changes).
Combination meals (lunch/dinner: n 258, breakfast: n 68, children’s: n 34) and their prices were identified from online menus; corresponding nutrition information for each menu item was obtained from a restaurant nutrition database (MenuStat). Linear models were used to examine the difference in total calories per dollar between default and higher-calorie combination meals, overall and by restaurant.
Ten large fast-food chain restaurants located in the fifteen most populous US cities in 2017–2018.
There were significantly more calories per dollar in higher-calorie v. default combination meals for lunch/dinner (default: 577 kJ (138 kcal)/dollar, higher-calorie: 707 kJ (169 kcal)/dollar, difference: 130 kJ (31 kcal)/dollar, P < 0·001) and breakfast (default: 536 kJ (128 kcal)/dollar, higher-calorie: 607 kJ (145 kcal)/dollar, difference: 71 kJ (17 kcal)/dollar, P = 0·009). Results for children’s meals were in the same direction but were not statistically significant (default: 536 kJ (128 kcal)/dollar, higher-calorie: 741 kJ (177 kcal)/dollar, difference: 205 kJ (49 kcal)/dollar, P = 0·053). Across restaurants, the percentage change in calories per dollar for higher-calorie v. default combination meals ranged from 0·1 % (Dunkin’ Donuts) to 55·0 % (Subway).
Higher-calorie combination meals in fast-food restaurants offer significantly more calories per dollar compared with default combination meals, suggesting there is a strong financial incentive for consumers to ‘upsize’ their orders. Future research should test price incentives for lower-calorie options to promote healthier restaurant choices.
A systematic review and network meta-analysis were conducted to assess the relative efficacy of internal or external teat sealants given at dry-off in dairy cattle. Controlled trials were eligible if they assessed the use of internal or external teat sealants, with or without concurrent antimicrobial therapy, compared to no treatment or an alternative treatment, and measured one or more of the following outcomes: incidence of intramammary infection (IMI) at calving, IMI during the first 30 days in milk (DIM), or clinical mastitis during the first 30 DIM. Risk of bias was based on the Cochrane Risk of Bias 2.0 tool with modified signaling questions. From 2280 initially identified records, 32 trials had data extracted for one or more outcomes. Network meta-analysis was conducted for IMI at calving. Use of an internal teat sealant (bismuth subnitrate) significantly reduced the risk of new IMI at calving compared to non-treated controls (RR = 0.36, 95% CI 0.25–0.72). For comparisons between antimicrobial and teat sealant groups, concerns regarding precision were seen. Synthesis of the primary research identified important challenges related to the comparability of outcomes, replication and connection of interventions, and quality of reporting of study conduct.
A systematic review and meta-analysis were conducted to determine the efficacy of selective dry-cow antimicrobial therapy compared to blanket therapy (all quarters/all cows). Controlled trials were eligible if any of the following were assessed: incidence of clinical mastitis during the first 30 DIM, frequency of intramammary infection (IMI) at calving, or frequency of IMI during the first 30 DIM. From 3480 identified records, nine trials were data extracted for IMI at calving. There was an insufficient number of trials to conduct meta-analysis for the other outcomes. Risk of IMI at calving in selectively treated cows was higher than blanket therapy (RR = 1.34, 95% CI = 1.13, 1.16), but substantial heterogeneity was present (I2 = 58%). Subgroup analysis showed that, for trials using internal teat sealants, there was no difference in IMI risk at calving between groups, and no heterogeneity was present. For trials not using internal teat sealants, there was an increased risk in cows assigned to a selective dry-cow therapy protocol, compared to blanket treatment, with substantial heterogeneity in this subgroup. However, the small number of trials and heterogeneity in the subgroup without internal teat sealants suggests that the relative risk between treatments may differ from the determined point estimates based on other unmeasured factors.
A systematic review and network meta-analysis were conducted to assess the relative efficacy of antimicrobial therapy given to dairy cows at dry-off. Eligible studies were controlled trials assessing the use of antimicrobials compared to no treatment or an alternative treatment, and assessed one or more of the following outcomes: incidence of intramammary infection (IMI) at calving, incidence of IMI during the first 30 days in milk (DIM), or incidence of clinical mastitis during the first 30 DIM. Databases and conference proceedings were searched for relevant articles. The potential for bias was assessed using the Cochrane Risk of Bias 2.0 algorithm. From 3480 initially identified records, 45 trials had data extracted for one or more outcomes. Network meta-analysis was conducted for IMI at calving. The use of cephalosporins, cloxacillin, or penicillin with aminoglycoside significantly reduced the risk of new IMI at calving compared to non-treated controls (cephalosporins, RR = 0.37, 95% CI 0.23–0.65; cloxacillin, RR = 0.55, 95% CI 0.38–0.79; penicillin with aminoglycoside, RR = 0.42, 95% CI 0.26–0.72). Synthesis revealed challenges with a comparability of outcomes, replication of interventions, definitions of outcomes, and quality of reporting. The use of reporting guidelines, replication among interventions, and standardization of outcome definitions would increase the utility of primary research in this area.
Invasive species drive biodiversity loss and lead to changes in parasite–host associations. Parasites are linked to invasions and can mediate invasion success and outcomes. We review theoretical and empirical research into parasites in biological invasions, focusing on a freshwater invertebrate study system. We focus on the effects of parasitic infection on host traits (behaviour and life history) that can mediate native/invader trophic interactions. We review evidence from the field and laboratory of parasite-driven changes in predation, intraguild predation and cannibalism. Theoretical work shows that the trait-mediated effects of parasites can be as strong as classical density effects and their impact on the host’s trophic interactions merits more consideration. We also report on evidence of broader cascading effects warranting deeper study. Biological invasion can lead to altered parasite–host associations. Focusing on amphipod invasions, we find patterns of parasite introduction and loss that mirror host invasion pathways, but also highlight the risks of introducing invasive parasites. Horizon scanning and impact predictions are vital in identifying future disease risks, potential pathways of introduction and suitable management measures for mitigation.
Introduction: Competency-based skills development has driven the evolution of medical education. Simulation-based education is established as an essential tool to supplement clinical encounters and it provides the opportunity for low-stakes practice of common and high-acuity low-occurrence (HALO) procedures and scenarios. This is particularly important for emergency medicine trainees working to build confidence, knowledge, and skills in the field. Methods: In the procedural training sessions, learners rotate through 6 small-group stations over a 3-hour period. Skills topics are determined from faculty input, prior session feedback, and literature reviews. Topics included chest tubes, airway intervention, lumbar punctures and trauma interventions. Online content and brief written materials are used for pre-session learning. The small groups use hands-on faculty-guided training, with real-time feedback. Printed materials supplement key learning points at the stations. A combination of low-fidelity task trainers and simulated patients are used for practice and demonstration. R3 EM residents have the opportunity to mentor junior learners. Brief participant surveys are distributed at each session to gather qualitative and quantitative feedback. Results: Feedback forms were completed by 79/85 (92.9%) learners over a period of 4 years (2015-2018). Participants included medical students (11.8%), EM residents (52.9%), and non-EM residents (35.3%). 84.8% (67/79) gave positive qualitative feedback on the sessions, citing points such as the beneficial practice opportunities, quality of instruction, and utility of the models. Updated surveys (N = 26) used a 5-point Likert scale (1 = disagree strongly; 5 strongly agree) in addition to qualitative feedback. Participants indicated that sessions were valuable, and informative (M = 4.692, SD = 0.462; M = 4.270, SD = 0.710). They reported increased understanding of procedures discussed, and they were likely to recommend the session (M = 4.301, SD = 0.606; M = 4.808, SD = 0.394). Conclusion: The ongoing evaluation of our mentor guided hands-on low-fidelity and hybrid simulation-based procedural skills sessions facilitates meaningful programmatic changes to best meet the needs of EM learners. Sessions also provide a forum for EM resident mentorship of junior learners. Feedback indicates learners enjoyed the sessions and found this to be an engaging and effective instructional modality.
The smr and qacA/B genes in Staphylococcus aureus confer tolerance to antiseptics and are associated with nosocomial acquisition of infection and underlying medical conditions. Such antiseptic tolerance (AT) genes have also been reported in coagulase-negative staphylococci (CoNS) and enterococci, however, few data are available regarding their prevalence. We sought to describe the frequency of AT genes among bloodstream isolates of S. aureus, CoNS and enterococci at Texas Children’s Hospital (TCH).
Banked CoNS, S. aureus and enterococci isolated from blood cultures collected bewteen October 1, 2016, and October 1, 2017, were obtained from the TCH clinical microbiology laboratory. All isolates underwent polymerase chain reaction (PCR) assay for the qacA/B and smr genes. Medical records were reviewed for all cases.
In total, 103 CoNS, 19 Enterococcus spp, and 119 S. aureus isolates were included in the study, and 80.6% of the CoNS possessed at least 1 AT gene compared to 37% of S. aureus and 43.8% of E. faecalis isolates (P < .001). Among CoNS bloodstream isolates, the presence of either AT gene was strongly associated with nosocomial infection (P < .001). The AT genes in S. aureus were associated with nosocomial infection (P = .025) as well as the diagnosis of central-line–associated bloodstream infection (CLABSI; P = .04) and recent hospitalizations (P < .001). We found no correlation with genotypic AT in E. faecalis and any clinical variable we examined.
Antiseptic tolerance is common among bloodstream staphylococci and E. faecalis isolates at TCH. Among CoNS, the presence of AT genes is strongly correlated with nosocomial acquisition of infection, consistent with previous studies in S. aureus. These data suggest that the healthcare environment contributes to AT among staphylococci.
Multiple studies have demonstrated that daily chlorhexidine gluconate (CHG) bathing is associated with a significant reduction in infections caused by gram-positive pathogens. However, there are limited data on the effectiveness of daily CHG bathing on gram-negative infections. The aim of this study was to determine whether daily CHG bathing is effective in reducing the rate of gram-negative infections in adult intensive care unit (ICU) patients.
We searched MEDLINE and 3 other databases for original studies comparing daily bathing with and without CHG. Two investigators extracted data independently on baseline characteristics, study design, form and concentration of CHG, incidence, and outcomes related to gram-negative infections. Data were combined using a random-effects model and pooled relative risk ratios (RRs), and 95% confidence intervals (CIs) were derived.
In total, 15 studies (n = 34,895 patients) met inclusion criteria. Daily CHG bathing was not significantly associated with a lower risk of gram-negative infections compared with controls (RR, 0.89; 95% CI, 0.73–1.08; P = .24). Subgroup analysis demonstrated that daily CHG bathing was not effective for reducing the risk of gram-negative infections caused by Acinetobacter, Escherichia coli, Klebsiella, Enterobacter, or Pseudomonas spp.
The use of daily CHG bathing was not associated with a lower risk of gram-negative infections. Further, better designed trials with adequate power and with gram-negative infections as the primary end point are needed.
The aim of this retrospective review was to assess the overall burden and trend in spinal tuberculosis (TB) at tertiary hospitals in the Western Cape Province of South Africa. All spinal TB cases seen at the province's three tertiary hospitals between 2012 and 2015 were identified and clinical records of each case assessed. Cases were subsequently classified as bacteriologically confirmed or clinically diagnosed and reported with accompanying clinical and demographic information. Odds ratios (OR) for severe spinal disease and corrective surgery in child vs. adult cases were calculated. A total of 393 cases were identified (319 adults, 74 children), of which 283 (72%) were bacteriologically confirmed. Adult cases decreased year-on-year (P = 0.04), however there was no clear trend in child cases. Kyphosis was present in 60/74 (81%) children and 243/315 (77%) adults with available imaging. Corrective spinal surgery was performed in 35/74 (47%) children and 80/319 (25%) adults (OR 2.7, 95% confidence interval 1.6–4.5, P = 0.0003). These findings suggest that Western Cape tertiary hospitals have experienced a substantial burden of spinal TB cases in recent years with a high proportion of severe presentation, particularly among children. Spinal TB remains a public health concern with increased vigilance required for earlier diagnosis, especially of child cases.