Debugging and consolidating multiple synthetic chromosomes reveals combinatorial genetic interactions.

The Sc2.0 project is building a eukaryotic synthetic genome from scratch. A major milestone has been achieved with all individual Sc2.0 chromosomes assembled. Here, we describe the consolidation of multiple synthetic chromosomes using advanced endoreduplication intercrossing with tRNA expression cassettes to generate a strain with 6.5 synthetic chromosomes. The 3D chromosome organization and transcript isoform profiles were evaluated using Hi-C and long-read direct RNA sequencing. We developed CRISPR Directed Biallelic URA3-assisted Genome Scan, or "CRISPR D-BUGS," to map phenotypic variants caused by specific designer modifications, known as "bugs." We first fine-mapped a bug in synthetic chromosome II (synII) and then discovered a combinatorial interaction associated with synIII and synX, revealing an unexpected genetic interaction that links transcriptional regulation, inositol metabolism, and tRNASerCGA abundance. Finally, to expedite consolidation, we employed chromosome substitution to incorporate the largest chromosome (synIV), thereby consolidating >50% of the Sc2.0 genome in one strain.

Genome-wide association reveals host-specific genomic traits in Escherichia coli.

BACKGROUND: Escherichia coli is an opportunistic pathogen which colonizes various host species. However, to what extent genetic lineages of E. coli are adapted or restricted to specific hosts and the genomic determinants of such adaptation or restriction is poorly understood. RESULTS: We randomly sampled E. coli isolates from four countries (Germany, UK, Spain, and Vietnam), obtained from five host species (human, pig, cattle, chicken, and wild boar) over 16 years, from both healthy and diseased hosts, to construct a collection of 1198 whole-genome sequenced E. coli isolates. We identified associations between specific E. coli lineages and the host from which they were isolated. A genome-wide association study (GWAS) identified several E. coli genes that were associated with human, cattle, or chicken hosts, whereas no genes associated with the pig host could be found. In silico characterization of nine contiguous genes (collectively designated as nan-9) associated with the human host indicated that these genes are involved in the metabolism of sialic acids (Sia). In contrast, the previously described sialic acid regulon known as sialoregulon (i.e. nanRATEK-yhcH, nanXY, and nanCMS) was not associated with any host species. In vitro growth experiments with a Δnan-9 E. coli mutant strain, using the sialic acids 5-N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) as sole carbon source, showed impaired growth behaviour compared to the wild-type. CONCLUSIONS: This study provides an extensive analysis of genetic determinants which may contribute to host specificity in E. coli. Our findings should inform risk analysis and epidemiological monitoring of (antimicrobial resistant) E. coli.

Mendelian randomisation study of body composition and depression in people of East Asian ancestry highlights potential setting-specific causality.

BACKGROUND: Extensive evidence links higher body mass index (BMI) to higher odds of depression in people of European ancestry. However, our understanding of the relationship across different settings and ancestries is limited. Here, we test the relationship between body composition and depression in people of East Asian ancestry. METHODS: Multiple Mendelian randomisation (MR) methods were used to test the relationship between (a) BMI and (b) waist-hip ratio (WHR) with depression. Firstly, we performed two-sample MR using genetic summary statistics from a recent genome-wide association study (GWAS) of depression (with 15,771 cases and 178,777 controls) in people of East Asian ancestry. We selected 838 single nucleotide polymorphisms (SNPs) correlated with BMI and 263 SNPs correlated with WHR as genetic instrumental variables to estimate the causal effect of BMI and WHR on depression using the inverse-variance weighted (IVW) method. We repeated these analyses stratifying by home location status: China versus UK or USA. Secondly, we performed one-sample MR in the China Kadoorie Biobank (CKB) in 100,377 participants. This allowed us to test the relationship separately in (a) males and females and (b) urban and rural dwellers. We also examined (c) the linearity of the BMI-depression relationship. RESULTS: Both MR analyses provided evidence that higher BMI was associated with lower odds of depression. For example, a genetically-instrumented 1-SD higher BMI in the CKB was associated with lower odds of depressive symptoms [OR: 0.77, 95% CI: 0.63, 0.95]. There was evidence of differences according to place of residence. Using the IVW method, higher BMI was associated with lower odds of depression in people of East Asian ancestry living in China but there was no evidence for an association in people of East Asian ancestry living in the USA or UK. Furthermore, higher genetic BMI was associated with differential effects in urban and rural dwellers within China. CONCLUSIONS: This study provides the first MR evidence for an inverse relationship between BMI and depression in people of East Asian ancestry. This contrasts with previous findings in European populations and therefore the public health response to obesity and depression is likely to need to differ based on sociocultural factors for example, ancestry and place of residence. This highlights the importance of setting-specific causality when using genetic causal inference approaches and data from diverse populations to test hypotheses. This is especially important when the relationship tested is not purely biological and may involve sociocultural factors.

Occupational physical activity, mortality and CHD events in the Italian Longitudinal Study.

PURPOSE: Several recent studies have suggested a 'physical activity paradox' whereby leisure-time physical activity benefits health, but occupational physical activity is harmful. However, other studies imply that occupational physical activity is beneficial. Using data from a nationally representative Italian sample, we investigate if the context, or domain, of physical activity matters for mortality and coronary heart disease (CHD) events. METHODS: Among 40,220 men and women aged 40-55 at baseline, we used Cox models to compare associations of occupational, domestic and leisure-time physical activity with risk of mortality and CHD events over a follow-up period of up to 14 years. We accounted for sociodemographic factors, smoking, body mass index (BMI), physical and mental health, and educational qualifications. RESULTS: Occupational physical activity was not significantly associated with risk of mortality or CHD events for women, or with CHD events for men. In crude models, risk of mortality was higher for men in the highest occupational activity group, compared to the lowest (HR 1.26, 95% CI 1.01, 1.57). This attenuated with adjustment for health-related behaviours, health, and education (HR 1.03, 95% CI 0.77, 1.38). In crude models, leisure-time physical activity was significantly associated with decreased mortality and CHD risk only for men. Domestic physical activity was not associated with either outcome for either gender. CONCLUSION: In a large sample of middle-aged Italian workers, we found limited evidence of harmful or beneficial effects of occupational physical activity on mortality or CHD events. However, confidence intervals were wide, and results consistent with a range of effects in both directions.

Socioeconomic position and adverse childhood experiences as risk factors for health-related behaviour change and employment adversity during the COVID-19 pandemic: insights from a prospective cohort study in the UK.

BACKGROUND: Non-pharmaceutical interventions to reduce the spread of COVID-19 may have disproportionately affected already disadvantaged populations. METHODS: We analysed data from 2710 young adult participants of the Avon Longitudinal Study of Parents and Children. We assessed the associations of socioeconomic position (SEP) and Adverse Childhood Experiences (ACEs, e.g. abuse, neglect, measures of family dysfunction) with changes to health-related behaviours (meals, snacks, exercise, sleep, alcohol and smoking/vaping), and to financial and employment status during the first UK lockdown between March-June 2020. RESULTS: Experiencing 4+ ACEs was associated with reporting decreased sleep quantity during lockdown (OR 1.53, 95% CI: 1.07-2.18) and increased smoking and/or vaping (OR 1.85, 95% CI: 0.99-3.43); no other associations were seen between ACEs or SEP and health-related behaviour changes. Adverse financial and employment changes were more likely for people with low SEP and for people who had experienced multiple ACEs; e.g. a history of 4+ ACEs was associated with being furloughed or on other leave during lockdown (OR 1.92, 95% CI: 1.35-2.74). CONCLUSIONS: In this sample of young adults, there was little evidence that lockdown worsened inequalities in health-related behaviours. However, adverse financial and employment consequences of lockdown were more likely to be experienced by people who have already experienced socioeconomic deprivation or childhood adversity, thereby widening social inequalities and demonstrating the need for support into adulthood for those with a history of ACEs.

Leveraging DNA-Methylation Quantitative-Trait Loci to Characterize the Relationship between Methylomic Variation, Gene Expression, and Complex Traits.

Characterizing the complex relationship between genetic, epigenetic, and transcriptomic variation has the potential to increase understanding about the mechanisms underpinning health and disease phenotypes. We undertook a comprehensive analysis of common genetic variation on DNA methylation (DNAm) by using the Illumina EPIC array to profile samples from the UK Household Longitudinal study. We identified 12,689,548 significant DNA methylation quantitative trait loci (mQTL) associations (p < 6.52 × 10-14) occurring between 2,907,234 genetic variants and 93,268 DNAm sites, including a large number not identified by previous DNAm-profiling methods. We demonstrate the utility of these data for interpreting the functional consequences of common genetic variation associated with > 60 human traits by using summary-data-based Mendelian randomization (SMR) to identify 1,662 pleiotropic associations between 36 complex traits and 1,246 DNAm sites. We also use SMR to characterize the relationship between DNAm and gene expression and thereby identify 6,798 pleiotropic associations between 5,420 DNAm sites and the transcription of 1,702 genes. Our mQTL database and SMR results are available via a searchable online database as a resource to the research community.

A phase II study of addition of pracinostat to a hypomethylating agent in patients with myelodysplastic syndromes who have not responded to previous hypomethylating agent therapy.

Hypomethylating agents (HMAs) are standard of care for higher-risk myelodysplastic syndromes (MDS). However, less than half of patients achieve objective responses and most eventually lose their response. Pracinostat is a pan-histone deacetylase inhibitor with demonstrated activity in advanced myeloid malignancies. This phase II study explored the benefit of adding pracinostat to HMAs in MDS patients who did not respond to single-agent HMA treatment. The goal was to estimate the clinical improvement rate [complete remission (CR), marrow CR, partial response (PR) and haematological improvement]. Group 1 included patients with primary/secondary HMA failures; Group 2 included those who did not achieve response but had stable disease (SD) after single-agent HMAs. Forty-five patients (39 Group 1, 6 Group 2) received a median of 3 cycles. Among all patients, 1 (2%) had CR, 7 (16%) had marrow CR and 18 (40%) had SD; disease progression occurred in 3 (7%). Median overall survival was 5·7/5·6 months for Group 1/2. Grade ≥3 adverse events occurred in 38 patients (84%) leading to treatment discontinuation in 12 (33%). Adding pracinostat to HMAs did not improve outcomes in patients previously treated with HMAs. Frequent dose modifications/early discontinuation resulted in suboptimal drug exposure. A reduced pracinostat dose may improve tolerability and efficacy.

A functional evolutionary approach to identify determinants of nucleosome positioning: a unifying model for establishing the genome-wide pattern.

Although the genomic pattern of nucleosome positioning is broadly conserved, quantitative aspects vary over evolutionary timescales. We identify the cis and trans determinants of nucleosome positioning using a functional evolutionary approach involving S. cerevisiae strains containing large genomic regions from other yeast species. In a foreign species, nucleosome depletion at promoters is maintained over poly(dA:dT) tracts, whereas internucleosome spacing and all other aspects of nucleosome positioning tested are not. Interestingly, the locations of the +1 nucleosome and RNA start sites shift in concert. Strikingly, in a foreign species, nucleosome-depleted regions occur fortuitously in coding regions, and they often act as promoters that are associated with a positioned nucleosome array linked to the length of the transcription unit. We suggest a three-step model in which nucleosome remodelers, general transcription factors, and the transcriptional elongation machinery are primarily involved in generating the nucleosome positioning pattern in vivo.

Telephone interventions for symptom management in adults with cancer.

BACKGROUND: People with cancer experience a variety of symptoms as a result of their disease and the therapies involved in its management. Inadequate symptom management has implications for patient outcomes including functioning, psychological well-being, and quality of life (QoL). Attempts to reduce the incidence and severity of cancer symptoms have involved the development and testing of psycho-educational interventions to enhance patients' symptom self-management. With the trend for care to be provided nearer patients' homes, telephone-delivered psycho-educational interventions have evolved to provide support for the management of a range of cancer symptoms. Early indications suggest that these can reduce symptom severity and distress through enhanced symptom self-management. OBJECTIVES: To assess the effectiveness of telephone-delivered interventions for reducing symptoms associated with cancer and its treatment. To determine which symptoms are most responsive to telephone interventions. To determine whether certain configurations (e.g. with/without additional support such as face-to-face, printed or electronic resources) and duration/frequency of intervention calls mediate observed cancer symptom outcome effects. SEARCH METHODS: We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 1); MEDLINE via OVID (1946 to January 2019); Embase via OVID (1980 to January 2019); (CINAHL) via Athens (1982 to January 2019); British Nursing Index (1984 to January 2019); and PsycINFO (1989 to January 2019). We searched conference proceedings to identify published abstracts, as well as SIGLE and trial registers for unpublished studies. We searched the reference lists of all included articles for additional relevant studies. Finally, we handsearched the following journals: Cancer, Journal of Clinical Oncology, Psycho-oncology, Cancer Practice, Cancer Nursing, Oncology Nursing Forum, Journal of Pain and Symptom Management, and Palliative Medicine. We restricted our search to publications published in English. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs that compared one or more telephone interventions with one other, or with other types of interventions (e.g. a face-to-face intervention) and/or usual care, with the stated aim of addressing any physical or psychological symptoms of cancer and its treatment, which recruited adults (over 18 years) with a clinical diagnosis of cancer, regardless of tumour type, stage of cancer, type of treatment, and time of recruitment (e.g. before, during, or after treatment). DATA COLLECTION AND ANALYSIS: We used Cochrane methods for trial selection, data extraction and analysis. When possible, anxiety, depressive symptoms, fatigue, emotional distress, pain, uncertainty, sexually-related and lung cancer symptoms as well as secondary outcomes are reported as standardised mean differences (SMDs) with 95% confidence intervals (CIs), and we presented a descriptive synthesis of study findings. We reported on findings according to symptoms addressed and intervention types (e.g. telephone only, telephone combined with other elements). As many studies included small samples, and because baseline scores for study outcomes often varied for intervention and control groups, we used change scores and associated standard deviations. The certainty of the evidence for each outcome was interpreted using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. MAIN RESULTS: Thirty-two studies were eligible for inclusion; most had moderate risk of bias,often related to blinding. Collectively, researchers recruited 6250 people and studied interventions in people with a variety of cancer types and across the disease trajectory, although many participants had breast cancer or early-stage cancer and/or were starting treatment. Studies measured symptoms of anxiety, depression, emotional distress, uncertainty, fatigue, and pain, as well as sexually-related symptoms and general symptom intensity and/or distress. Interventions were primarily delivered by nurses (n = 24), most of whom (n = 16) had a background in oncology, research, or psychiatry. Ten interventions were delivered solely by telephone; the rest combined telephone with additional elements (i.e. face-to-face consultations and digital/online/printed resources). The number of calls delivered ranged from 1 to 18; most interventions provided three or four calls. Twenty-one studies provided evidence on effectiveness of telephone-delivered interventions and the majority appeared to reduce symptoms of depression compared to control. Nine studies contributed quantitative change scores (CSs) and associated standard deviation results (or these could be calculated). Likewise, many telephone interventions appeared effective when compared to control in reducing anxiety (16 studies; 5 contributed quantitative CS results); fatigue (9 studies; 6 contributed to quantitative CS results); and emotional distress (7 studies; 5 contributed quantitative CS results). Due to significant clinical heterogeneity with regards to interventions introduced, study participants recruited, and outcomes measured, meta-analysis was not conducted. For other symptoms (uncertainty, pain, sexually-related symptoms, dyspnoea, and general symptom experience), evidence was limited; similarly meta-analysis was not possible, and results from individual studies were largely conflicting, making conclusions about their management through telephone-delivered interventions difficult to draw. Heterogeneity was considerable across all trials for all outcomes. Overall, the certainty of evidence was very low for all outcomes in the review. Outcomes were all downgraded due to concerns about overall risk of bias profiles being frequently unclear, uncertainty in effect estimates and due to some inconsistencies in results and general heterogeneity. Unsubstantiated evidence suggests that telephone interventions in some capacity may have a place in symptom management for adults with cancer. However, in the absence of reliable and homogeneous evidence, caution is needed in interpreting the narrative synthesis. Further, there were no clear patterns across studies regarding which forms of interventions (telephone alone versus augmented with other elements) are most effective. It is impossible to conclude with any certainty which forms of telephone intervention are most effective in managing the range of cancer-related symptoms that people with cancer experience. AUTHORS' CONCLUSIONS: Telephone interventions provide a convenient way of supporting self-management of cancer-related symptoms for adults with cancer. These interventions are becoming more important with the shift of care closer to patients' homes, the need for resource/cost containment, and the potential for voluntary sector providers to deliver healthcare interventions. Some evidence supports the use of telephone-delivered interventions for symptom management for adults with cancer; most evidence relates to four commonly experienced symptoms - depression, anxiety, emotional distress, and fatigue. Some telephone-delivered interventions were augmented by combining them with face-to-face meetings and provision of printed or digital materials. Review authors were unable to determine whether telephone alone or in combination with other elements provides optimal reduction in symptoms; it appears most likely that this will vary by symptom. It is noteworthy that, despite the potential for telephone interventions to deliver cost savings, none of the studies reviewed included any form of health economic evaluation. Further robust and adequately reported trials are needed across all cancer-related symptoms, as the certainty of evidence generated in studies within this review was very low, and reporting was of variable quality. Researchers must strive to reduce variability between studies in the future. Studies in this review are characterised by clinical and methodological diversity; the level of this diversity hindered comparison across studies. At the very least, efforts should be made to standardise outcome measures. Finally, studies were compromised by inclusion of small samples, inadequate concealment of group allocation, lack of observer blinding, and short length of follow-up. Consequently, conclusions related to symptoms most amenable to management by telephone-delivered interventions are tentative.

Socioeconomic Position and DNA Methylation Age Acceleration Across the Life Course.

Accelerated DNA methylation age is linked to all-cause mortality and environmental factors, but studies of associations with socioeconomic position are limited. Researchers generally use small selected samples, and it is unclear how findings obtained with 2 commonly used methods for calculating methylation age (the Horvath method and the Hannum method) translate to general population samples including younger and older adults. Among 1,099 United Kingdom adults aged 28-98 years in 2011-2012, we assessed the relationship of Horvath and Hannum DNA methylation age acceleration with a range of social position measures: current income and employment, education, income and unemployment across a 12-year period, and childhood social class. Accounting for confounders, participants who had been less advantaged in childhood were epigenetically "older" as adults: In comparison with participants who had professional/managerial parents, Hannum age was 1.07 years higher (95% confidence interval: 0.20, 1.94) for participants with parents in semiskilled/unskilled occupations and 1.85 years higher (95% confidence interval: 0.67, 3.02) for those without a working parent at age 14 years. No other robust associations were seen. Results accord with research implicating early life circumstances as critical for DNA methylation age in adulthood. Since methylation age acceleration as measured by the Horvath and Hannum estimators appears strongly linked to chronological age, researchers examining associations with the social environment must take steps to avoid age-related confounding.

Associations of C-reactive protein and psychological distress are modified by antidepressants, supporting an inflammatory depression subtype: Findings from UKHLS.

BACKGROUND: Clinical evidence increasingly suggests inflammation may be important specifically for an etiologically distinct depression subtype, characterised by resistance to antidepressant medication. However, epidemiological investigations of the relationship of inflammation with depression and psychological distress have failed to acknowledge these developments, which may have resulted in bias or masking of associations driven by the subtype. This may have contributed to inconsistent results in epidemiological studies, and equivocal support for an inflammation-depression link. METHODS: An antidepressant-resistant, inflammatory depression subtype would result in stronger associations of depressive symptomatology with inflammation among antidepressant users than non-users, due to over-representation of subtype individuals among antidepressant users experiencing severe or persistent symptoms. We investigate, in a sample of 10,363 UK adults aged 16-98, modification by antidepressants of cross-sectional and longitudinal associations between C-reactive protein and psychological distress (General Health Questionnaire score, GHQ). We account for confounding by age, gender, income, inflammatory somatic illness, body mass index and, in longitudinal models, baseline psychological distress. Sensitivity analyses consider smoking, ethnicity, and other medications. RESULTS: Robust associations of log-CRP and GHQ were seen for antidepressant users but not for non-users in both cross-sectional (coeff: 0.54, p=0.01vs 0.06, p=0.28) and longitudinal models (coeff: 0.57, p=0.006vs 0.04, p=0.39 two waves post-baseline). Cross-sectional associations were strongest for tricyclic users, and longitudinal associations strongest for SSRI users. In multilevel, repeated-measures longitudinal models, associations for antidepressant users peaked two waves after baseline before declining. CONCLUSIONS: Results suggest evidence for existence of an inflammatory depression subtype. Previous studies' exclusion of antidepressant users and failure to consider interactive effects may have obscured associations driven by the subgroup. Follow-up work is now needed in community samples with clinical depression measures and prescription histories, to further elucidate the mechanisms involved.

Unemployment and inflammatory markers in England, Wales and Scotland, 1998-2012: Meta-analysis of results from 12 studies.

INTRODUCTION: Unemployment represents for many affected individuals a substantial source of psychosocial stress, and is linked to both increased risk of morbidity and mortality and adverse health-related behaviours. Few studies have examined the association of unemployment with systemic inflammation, a plausible mediator of the associations of psychosocial stress and health, and results are mixed and context dependent. This study examines the association of unemployment with C-reactive protein (CRP) and fibrinogen, two markers of systemic inflammation. METHODS: A random-effects meta-analysis was performed using a multilevel modelling approach, including 12 national UK surveys of working-age participants in which CRP and fibrinogen were measured between 1998 and 2012 (N=30,037 economically active participants). The moderating impact of participant age and UK country was explored. RESULTS: CRP and fibrinogen were elevated in unemployed compared to employed participants; jobseekers were also more likely (Odds Ratio: 1.39, p<0.001) to have CRP levels corresponding to high cardiovascular risk (>3mg/L), after adjustment for age, gender, education, long-term illness, smoking, and body mass index. Associations were not explained by mental health. Associations peaked in middle-age, and were stronger in Scotland and Wales than in England. CONCLUSIONS: Our study demonstrates that systemic inflammation is associated with an important but little-studied aspect of the social environment, as it is elevated in unemployed compared to employed survey participants. Modifications suggest the association of unemployment and inflammation is substantially influenced by contextual factors, and may be especially strong in Wales, where further investigation of this relationship is needed.

Unemployment, underweight, and obesity: Findings from Understanding Society (UKHLS).

Elevated morbidity and mortality among jobseekers may be partly explained by adiposity, but previous studies of unemployment and body mass index (BMI), which have usually modelled associations as linear, have produced inconsistent results. However, both underweight and obesity are associated with mortality, and both weight loss and weight gain associated with a stressful environment. If unemployment is associated with both underweight and obesity for different subgroups, these associations may previously have masked each other, whilst affecting health through divergent pathways. We investigated whether there is a previously overlooked U-shaped association of unemployment and BMI, which could help explain jobseekers' elevated morbidity and mortality, and identify groups vulnerable to underweight and obesity during unemployment. We used multinomial models to simultaneously investigate associations of unemployment with BMI-defined underweight, overweight, and obesity in 10,737 working-age UK adults from Understanding Society (UKHLS) in 2010-12. Moderating impacts of unemployment duration, demographic factors and smoking were explored. Current jobseekers were more likely to be underweight (Odds ratio (OR): 4.05, 95% confidence interval (CI): 2.12-7.73) and less likely to be overweight (OR: 0.71, CI: 0.55, 0.92) adjusted for gender, age, education, health, smoking and physical activity, while unemployed non-smokers had increased odds of obesity (OR: 1.52, CI: 1.06-2.18). Underweight and overweight associations were more apparent for longer-term jobseekers, men, and jobseekers from lower-income households. We conclude that unemployment is associated with underweight and, in nonsmokers, obesity. Results show the unemployment-adiposity relationship cannot be properly studied assuming unidirectionality of effects, and suggest unemployment may affect health of different groups via divergent adiposity-mediated pathways.

The Clostridium difficile cell wall protein CwpV confers phase-variable phage resistance.

Bacteriophages are present in virtually all ecosystems, and bacteria have developed multiple antiphage strategies to counter their attacks. Clostridium difficile is an important pathogen causing severe intestinal infections in humans and animals. Here we show that the conserved cell-surface protein CwpV provides antiphage protection in C. difficile. This protein, for which the expression is phase-variable, is classified into five types, each differing in their repeat-containing C-terminal domain. When expressed constitutively from a plasmid or the chromosome of locked 'ON' cells of C. difficile R20291, CwpV conferred antiphage protection. Differences in the level of phage protection were observed depending on the phage morphological group, siphophages being the most sensitive with efficiency of plaquing (EOP) values of < 5 × 10(-7) for phages ϕCD38-2, ϕCD111 and ϕCD146. Protection against the myophages ϕMMP01 and ϕCD52 was weaker, with EOP values between 9.0 × 10(-3) and 1.1 × 10(-1). The C-terminal domain of CwpV carries the antiphage activity and its deletion, or part of it, significantly reduced the antiphage protection. CwpV does not affect phage adsorption, but phage DNA replication is prevented, suggesting a mechanism reminiscent of superinfection exclusion systems normally encoded on prophages. CwpV thus represents a novel ubiquitous host-encoded and phase-variable antiphage system in C. difficile.

Induced ectopic expression of HigB toxin in Mycobacterium tuberculosis results in growth inhibition, reduced abundance of a subset of mRNAs and cleavage of tmRNA.

In Mycobacterium tuberculosis, the genes Rv1954A-Rv1957 form an operon that includes Rv1955 and Rv1956 which encode the HigB toxin and the HigA antitoxin respectively. We are interested in the role and regulation of this operon, since toxin-antitoxin systems have been suggested to play a part in the formation of persister cells in mycobacteria. To investigate the function of the higBA locus, effects of toxin expression on mycobacterial growth and transcript levels were assessed in M. tuberculosis H37Rv wild type and in an operon deletion background. We show that expression of HigB toxin in the absence of HigA antitoxin arrests growth and causes cell death in M. tuberculosis. We demonstrate HigB expression to reduce the abundance of IdeR and Zur regulated mRNAs and to cleave tmRNA in M. tuberculosis, Escherichia coli and Mycobacterium smegmatis. This study provides the first identification of possible target transcripts of HigB in M. tuberculosis.

Arabidopsis thaliana and Pisum sativum models demonstrate that root colonization is an intrinsic trait of Burkholderia cepacia complex bacteria.

Burkholderia cepacia complex (Bcc) bacteria possess biotechnologically useful properties that contrast with their opportunistic pathogenicity. The rhizosphere fitness of Bcc bacteria is central to their biocontrol and bioremediation activities. However, it is not known whether this differs between species or between environmental and clinical strains. We investigated the ability of 26 Bcc strains representing nine different species to colonize the roots of Arabidopsis thaliana and Pisum sativum (pea). Viable counts, scanning electron microscopy and bioluminescence imaging were used to assess root colonization, with Bcc bacteria achieving mean (±sem) levels of 2.49±0.23×10(6) and 5.16±1.87×10(6) c.f.u. per centimetre of root on the A. thaliana and P. sativum models, respectively. The A. thaliana rhizocompetence model was able to reveal loss of colonization phenotypes in Burkholderia vietnamiensis G4 transposon mutants that had only previously been observed in competition experiments on the P. sativum model. Different Bcc species colonized each plant model at different rates, and no statistical difference in root colonization was observed between isolates of clinical or environmental origin. Loss of the virulence-associated third chromosomal replicon (>1 Mb DNA) did not alter Bcc root colonization on A. thaliana. In summary, Bcc bacteria possess intrinsic root colonization abilities irrespective of their species or source. As Bcc rhizocompetence does not require their third chromosomal replicon, the possibility of using synthetic biology approaches to engineer virulence-attenuated biotechnological strains is tractable.

Genetic associations of risk behaviours and educational achievement.

Risk behaviours are common in adolescent and persist into adulthood, people who engage in more risk behaviours are more likely to have lower educational attainment. We applied genetic causal inference methods to explore the causal relationship between adolescent risk behaviours and educational achievement. Risk behaviours were phenotypically associated with educational achievement at age 16 after adjusting for confounders (-0.11, 95%CI: -0.11, -0.09). Genomic-based restricted maximum likelihood (GREML) results indicated that both traits were heritable and have a shared genetic architecture (Risk h 2 = 0.18, 95% CI: -0.11,0.47; education h 2 = 0.60, 95%CI: 0.50,0.70). Consistent with the phenotypic results, genetic variation associated with risk behaviour was negatively associated with education ( r g = -0.51, 95%CI: -1.04,0.02). Lastly, the bidirectional MR results indicate that educational achievement or a closely related trait is likely to affect risk behaviours PGI (ß=-1.04, 95% CI: -1.41, -0.67), but we found little evidence that the genetic variation associated with risk behaviours affected educational achievement (ß=0.00, 95% CI: -0.24,0.24). The results suggest engagement in risk behaviour may be partly driven by educational achievement or a closely related trait.

Psychological predictors of performance-based physical functioning among pediatric pain program participants.

PURPOSE: The purpose of the present study was to evaluate changes in performance-based physical functioning and investigate psychological predictors of physical functioning over time in pediatric patients with chronic pain who completed an interdisciplinary rehabilitation intensive outpatient program (IOP). METHODS: Participants (N = 55; mean age = 14.92 years; 12.7% male, 87.3% female; 83.6% White, 5.6% African-American/Black; 9.1% Latinx) completed baseline measures assessing pain intensity and modifiable psychological factors (i.e., pain catastrophizing, kinesiophobia, anxiety and depressive symptoms). Participants were administered performance-based assessments of physical functioning (i.e., physical endurance, high-level motor abilities) before and after IOP completion. RESULTS: Pain intensity was not significantly associated with physical functioning at either timepoint. There was significant improvement on measures of physical functioning after completion of the IOP when controlling for the effects of sex, race, and ethnicity. Depressive symptoms were associated with baseline physical endurance, ß = - .28, p = .047, while pain catastrophizing was associated with baseline gross motor abilities, ß = - .28, p = .032. CONCLUSION: Participation in an IOP led to significant improvement in physical endurance and high-level motor ability. Depressive symptoms and pain catastrophizing were associated with physical functioning at baseline but not post-program completion. Integration of pain psychology and physical therapy in an IOP can help address the interrelated psychological and physical factors impacting physical functioning to improve outcomes for children with chronic pain.

Single and Combined Effects of Cannabigerol (CBG) and Cannabidiol (CBD) in Mouse Models of Oxaliplatin-Associated Mechanical Sensitivity, Opioid Antinociception, and Naloxone-Precipitated Opioid Withdrawal.

Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most prevalent and dose-limiting complications in chemotherapy patients, with estimates of at least 30% of patients experiencing persistent neuropathy for months or years after treatment cessation. An emerging potential intervention for the treatment of CIPN is cannabinoid-based pharmacotherapies. We have previously demonstrated that treatment with the psychoactive CB1/CB2 cannabinoid receptor agonist Δ9-tetrahydrocannabinol (Δ9-THC) or the non-psychoactive, minor phytocannabinoid cannabidiol (CBD) can attenuate paclitaxel-induced mechanical sensitivity in a mouse model of CIPN. We then showed that the two compounds acted synergically when co-administered in the model, giving credence to the so-called entourage effect. We and others have also demonstrated that CBD can attenuate several opioid-associated behaviors. Most recently, it was reported that another minor cannabinoid, cannabigerol (CBG), attenuated cisplatin-associated mechanical sensitivity in mice. Therefore, the goals of the present set of experiments were to determine the single and combined effects of cannabigerol (CBG) and cannabidiol (CBD) in oxaliplatin-associated mechanical sensitivity, naloxone-precipitated morphine withdrawal, and acute morphine antinociception in male C57BL/6 mice. Results demonstrated that CBG reversed oxaliplatin-associated mechanical sensitivity only under select dosing conditions, and interactive effects with CBD were sub-additive or synergistic depending upon dosing conditions too. Pretreatment with a selective α2-adrenergic, CB1, or CB2 receptor selective antagonist significantly attenuated the effect of CBG. CBG and CBD decreased naloxone-precipitated jumping behavior alone and acted synergistically in combination, while CBG attenuated the acute antinociceptive effects of morphine and CBD. Taken together, CBG may have therapeutic effects like CBD as demonstrated in rodent models, and its interactive effects with opioids or other phytocannabinoids should continue to be characterized.