A Genome-wide Framework for Mapping Gene Regulation via Cellular Genetic Screens.

Over one million candidate regulatory elements have been identified across the human genome, but nearly all are unvalidated and their target genes uncertain. Approaches based on human genetics are limited in scope to common variants and in resolution by linkage disequilibrium. We present a multiplex, expression quantitative trait locus (eQTL)-inspired framework for mapping enhancer-gene pairs by introducing random combinations of CRISPR/Cas9-mediated perturbations to each of many cells, followed by single-cell RNA sequencing (RNA-seq). Across two experiments, we used dCas9-KRAB to perturb 5,920 candidate enhancers with no strong a priori hypothesis as to their target gene(s), measuring effects by profiling 254,974 single-cell transcriptomes. We identified 664 (470 high-confidence) cis enhancer-gene pairs, which were enriched for specific transcription factors, non-housekeeping status, and genomic and 3D conformational proximity to their target genes. This framework will facilitate the large-scale mapping of enhancer-gene regulatory interactions, a critical yet largely uncharted component of the cis-regulatory landscape of the human genome.

A Single-Cell Atlas of In Vivo Mammalian Chromatin Accessibility.

We applied a combinatorial indexing assay, sci-ATAC-seq, to profile genome-wide chromatin accessibility in ∼100,000 single cells from 13 adult mouse tissues. We identify 85 distinct patterns of chromatin accessibility, most of which can be assigned to cell types, and ∼400,000 differentially accessible elements. We use these data to link regulatory elements to their target genes, to define the transcription factor grammar specifying each cell type, and to discover in vivo correlates of heterogeneity in accessibility within cell types. We develop a technique for mapping single cell gene expression data to single-cell chromatin accessibility data, facilitating the comparison of atlases. By intersecting mouse chromatin accessibility with human genome-wide association summary statistics, we identify cell-type-specific enrichments of the heritability signal for hundreds of complex traits. These data define the in vivo landscape of the regulatory genome for common mammalian cell types at single-cell resolution.

Cell-free DNA Comprises an In Vivo Nucleosome Footprint that Informs Its Tissues-Of-Origin.

Nucleosome positioning varies between cell types. By deep sequencing cell-free DNA (cfDNA), isolated from circulating blood plasma, we generated maps of genome-wide in vivo nucleosome occupancy and found that short cfDNA fragments harbor footprints of transcription factors. The cfDNA nucleosome occupancies correlate well with the nuclear architecture, gene structure, and expression observed in cells, suggesting that they could inform the cell type of origin. Nucleosome spacing inferred from cfDNA in healthy individuals correlates most strongly with epigenetic features of lymphoid and myeloid cells, consistent with hematopoietic cell death as the normal source of cfDNA. We build on this observation to show how nucleosome footprints can be used to infer cell types contributing to cfDNA in pathological states such as cancer. Since this strategy does not rely on genetic differences to distinguish between contributing tissues, it may enable the noninvasive monitoring of a much broader set of clinical conditions than currently possible.

Cell-cell communication between malaria-infected red blood cells via exosome-like vesicles.

Cell-cell communication is an important mechanism for information exchange promoting cell survival for the control of features such as population density and differentiation. We determined that Plasmodium falciparum-infected red blood cells directly communicate between parasites within a population using exosome-like vesicles that are capable of delivering genes. Importantly, communication via exosome-like vesicles promotes differentiation to sexual forms at a rate that suggests that signaling is involved. Furthermore, we have identified a P. falciparum protein, PfPTP2, that plays a key role in efficient communication. This study reveals a previously unidentified pathway of P. falciparum biology critical for survival in the host and transmission to mosquitoes. This identifies a pathway for the development of agents to block parasite transmission from the human host to the mosquito.

The single-cell transcriptional landscape of mammalian organogenesis.

Mammalian organogenesis is a remarkable process. Within a short timeframe, the cells of the three germ layers transform into an embryo that includes most of the major internal and external organs. Here we investigate the transcriptional dynamics of mouse organogenesis at single-cell resolution. Using single-cell combinatorial indexing, we profiled the transcriptomes of around 2 million cells derived from 61 embryos staged between 9.5 and 13.5 days of gestation, in a single experiment. The resulting 'mouse organogenesis cell atlas' (MOCA) provides a global view of developmental processes during this critical window. We use Monocle 3 to identify hundreds of cell types and 56 trajectories, many of which are detected only because of the depth of cellular coverage, and collectively define thousands of corresponding marker genes. We explore the dynamics of gene expression within cell types and trajectories over time, including focused analyses of the apical ectodermal ridge, limb mesenchyme and skeletal muscle.

Disparities in Tuberculosis Incidence by Race and Ethnicity Among the U.S.-Born Population in the United States, 2011 to 2021 : An Analysis of National Disease Registry Data.

BACKGROUND: Elevated tuberculosis (TB) incidence rates have recently been reported for racial/ethnic minority populations in the United States. Tracking such disparities is important for assessing progress toward national health equity goals and implementing change. OBJECTIVE: To quantify trends in racial/ethnic disparities in TB incidence among U.S.-born persons. DESIGN: Time-series analysis of national TB registry data for 2011 to 2021. SETTING: United States. PARTICIPANTS: U.S.-born persons stratified by race/ethnicity. MEASUREMENTS: TB incidence rates, incidence rate differences, and incidence rate ratios compared with non-Hispanic White persons; excess TB cases (calculated from incidence rate differences); and the index of disparity. Analyses were stratified by sex and by attribution of TB disease to recent transmission and were adjusted for age, year, and state of residence. RESULTS: In analyses of TB incidence rates for each racial/ethnic population compared with non-Hispanic White persons, incidence rate ratios were as high as 14.2 (95% CI, 13.0 to 15.5) among American Indian or Alaska Native (AI/AN) females. Relative disparities were greater for females, younger persons, and TB attributed to recent transmission. Absolute disparities were greater for males. Excess TB cases in 2011 to 2021 represented 69% (CI, 66% to 71%) and 62% (CI, 60% to 64%) of total cases for females and males, respectively. No evidence was found to indicate that incidence rate ratios decreased over time, and most relative disparity measures showed small, statistically nonsignificant increases. LIMITATION: Analyses assumed complete TB case diagnosis and self-report of race/ethnicity and were not adjusted for medical comorbidities or social determinants of health. CONCLUSION: There are persistent disparities in TB incidence by race/ethnicity. Relative disparities were greater for AI/AN persons, females, and younger persons, and absolute disparities were greater for males. Eliminating these disparities could reduce overall TB incidence by more than 60% among the U.S.-born population. PRIMARY FUNDING SOURCE: Centers for Disease Control and Prevention.

Global HIV Incidence Analysis and Implications for Affordability Using Long-Acting Cabotegravir Versus Continuous and Event-Driven Oral Preexposure Prophylaxis.

BACKGROUND: The HIV Prevention Trials Network (HPTN) 083/084 trials showed up to 88% increased efficacy of long-acting cabotegravir (CAB-LA) versus continuous oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC). However, CAB-LA's high price limits the number of people who can be treated within fixed prevention budgets. Global human immunodeficiency virus (HIV) prevention budgets are highly limited, with TDF/FTC widely available as a low-cost generic. In randomized clinical trials, event-driven TDF/FTC has shown similar preventive efficacy to continuous TDF/FTC. METHODS: A systematic review of global HIV incidence studies was conducted. Weighted incidence was calculated in each at-risk population. HIV infection rates were evaluated for 5 prevention strategies, with additional HIV testing, education, and service access costs assumed for each ($18 per person per year). Assumed efficacies were 90% (continuous CAB-LA), 60% (continuous TDF/FTC), and 60% (event-driven TDF/FTC). Using weighted incidence and an assumed 100 000 target population, annual HIV infection rates by population were calculated for each prevention strategy. RESULTS: Ninety-eight studies in 5 230 189 individuals were included. Incidence per 100 person-years ranged from 0.03 (blood donors) to 3.82 (people who inject drugs). Using the number needed to treat to benefit for each strategy, a mean incidence of 2.6 per 100 person-years in at-risk populations, and a 100 000 target population, current-price continuous CAB-LA cost $949 487 per HIV infection successfully prevented, followed by target-price CAB-LA ($11 453), continuous TDF/FTC ($4231), and event-driven TDF/FTC ($1923). CONCLUSIONS: High prices of CAB-LA limit numbers treatable within fixed budgets. Low-cost event-driven TDF/FTC consistently prevents the most HIV infections within fixed budgets.

One-year follow-up after active aortic aneurysm sac treatment with shape memory polymer devices during endovascular aneurysm repair.

OBJECTIVE: To determine the safety and efficacy of treating abdominal aortic aneurysm (AAA) sacs with polyurethane shape memory polymer (SMP) devices during endovascular aneurysm repair (EVAR), using a technique to fully treat the target lumen after endograft placement (aortic flow volume minus the endograft volume). SMP devices self-expand in the sac to form a porous scaffold that supports thrombosis throughout its structure. METHODS: Two identical prospective, multicenter, single-arm studies were conducted in New Zealand and the Netherlands. The study population was adult candidates for elective EVAR of an infrarenal AAA (diameter of ≥55 mm in men and ≥50 mm in women). Key exclusion criteria were an inability to adequately seal a common iliac artery aneurysm, patent sac feeding vessels of >4 mm, and a target lumen volume of <20 mL or >135 mL. Target lumen volumes were estimated by subtracting endograft volumes from preprocedural imaging-based flow lumen volumes. SMP devices were delivered immediately after endograft deployment via a 6F sheath jailed in a bowed position in the sac. The primary efficacy end point was technical success, defined as filling the actual target lumen volume with fully expanded SMP at the completion of the procedure. Secondary efficacy outcome measures during follow-up were the change in sac volume and diameter, rate of type II endoleak and type I or III endoleaks, and the rate of open repair and related reinterventions, with data collection at 30 days, 6 months, and 1 year (to date). Baseline sac volumes and diameters for change in sac size analyses were determined from 30-day imaging studies. Baseline and follow-up volumes were normalized by subtraction of the endograft volume. RESULTS: Of 34 patients treated with SMP devices and followed per protocol, 33 patients were evaluable at 1 year. Preprocedural aneurysm volume was 181.4 mL (95% confidence interval [CI], 150.7-212.1 mL) and preprocedural aneurysm diameter was 60.8 mm (95% CI, 57.8-63.9 mm). The target lumen volume was 56.3 mL (95% CI, 46.9-65.8 mL). Technical success was 100% and the ratio of SMP fully expanded volume to estimated target lumen volume was 1.4 ± 0.3. Baseline normalized sac volume and diameter were 140.7 mL (95% CI, 126.6-154.9 mL) and 61.0 mm (95% CI, 59.7-62.3 mm). The adjusted mean percentage change in normalized volume at 1 year was -28.8% (95% CI, -35.3 to -22.3%; P < .001). The adjusted mean change in sac diameter at 1 year was -5.9 mm (95% CI, -7.5 to -4.4 mm; P < .001). At 1 year, 81.8% of patients (95% CI, 64.5%-93.0%) achieved a ≥10% decrease in normalized volume and 57.6% of patients (95% CI, 39.2%-74.5%) achieved a ≥5 mm decrease in diameter. No device- or study procedure-related major adverse events occurred through 1 year after the procedure. CONCLUSIONS: Treatment of AAA sacs with SMP devices during EVAR resulted in significant sac volume and diameter regression at 1 year with an acceptable safety profile in this prospective study.

Can the delivery of behavioural support be improved in the NHS England Low-Calorie Diet Programme? An observational study of behaviour change techniques.

BACKGROUND: Previous research has illustrated a drift in the fidelity of behaviour change techniques (BCTs) during the design of the pilot NHS England Low-Calorie Diet (NHS-LCD) Programme. This study evaluated a subsequent domain of fidelity, intervention delivery. Two research questions were addressed: (1) To what extent were BCTs delivered with fidelity to providers programme plans? (2) What were the observed barriers and facilitators to delivery? METHODS: A mixed-methods sequential explanatory design was employed. Remote delivery of one-to-one and group-based programmes were observed. A BCT checklist was developed using the BCT Taxonomy v1; BCTs were coded as present, partially delivered, or absent during live sessions. Relational content analysis of field notes identified observed barriers and facilitators to fidelity. RESULTS: Observations of 122 sessions across eight samples and two service providers were completed. Delivery of the complete NHS-LCD was observed for five samples. Fidelity ranged from 33% to 70% across samples and was higher for group-based delivery models (64%) compared with one-to-one models (46%). Barriers and facilitators included alignment with the programme's target behaviours and outcomes, session content, time availability and management, group-based remote delivery, and deviation from the session plan. CONCLUSIONS: Overall, BCTs were delivered with low-to-moderate fidelity. Findings indicate a dilution in fidelity during the delivery of the NHS-LCD and variation in the fidelity of programmes delivered across England. Staff training could provide opportunities to practice the delivery of BCTs. Programme-level changes such as structured activities supported by participant materials and with sufficient allocated time, might improve the delivery of BCTs targeting self-regulation.

A Randomized Controlled Trial of Topical Analgesia Post-Hemorrhoidectomy (TAPH Trial).

BACKGROUND: Postoperative pain remains the greatest problem after hemorrhoidectomy. Pain is hypothesized to arise from bacterial infection, sphincter spasm, and local inflammation. OBJECTIVE: A randomized controlled factorial trial was conducted to assess the effects of metronidazole, diltiazem, and lidocaine on post-hemorrhoidectomy pain. DESIGN: A double blinded randomized controlled factorial trial. SETTINGS: A multicenter trial was conducted in Auckland, New Zealand. PATIENTS: 192 Participants were randomized (1:1:1:1) into four parallel arms. INTERVENTIONS: Participants were randomized into one of four groups receiving topical treatment with 10% metronidazole (M), 10% metronidazole + 2% diltiazem (MD), 10% metronidazole + 4% lidocaine (ML), or 10% metronidazole + 2% diltiazem + 4% lidocaine (MDL). Participants were instructed to apply to the anal verge 3 times daily for 7 days. MAIN OUTCOME MEASURES: The primary outcome was pain on the visual analogue scale on day 4. The secondary outcomes included analgesia usage, pain on bowel motion, and functional recovery index. RESULTS: There was no significant difference in the pain and recovery scores when diltiazem or lidocaine was added to metronidazole (score difference between presence and absence of D in the formulation: -3.69, 95% CI: -13.3, 5.94, p = 0.46; between presence and absence of L: -5.67, 95% CI: -15.5, 3.80, p = 0.24). The combination of MDL did not further reduce pain. Secondary analysis revealed a significant difference between the best (ML) and worst (MDL) groups in both pain and functional recovery scores. There were no significant differences in analgesic usage, complications, or return to work between the groups. No clinically important adverse events were reported. The adverse event rate did not change in the intervention groups. LIMITATIONS: Topical metronidazole was utilized in the control group, rather than a pure placebo. CONCLUSION: There was no significant difference in pain when topical diltiazem or lidocaine, or both, was added to topical metronidazole. CLINICAL TRIAL REGISTRATION IDENTIFIER: NCT04276298.

Left Atrial Appendage Occlusion Versus Direct Oral Anticoagulants in the Prevention of Ischaemic Stroke in Patients with Atrial Fibrillation.

Introduction Existing randomised controlled trials assessing the safety and efficacy of left atrial appendage occlusion (LAAO) in atrial fibrillation (AF) were of relatively small sample size, or included patients who could receive oral anticoagulant treatment after device implantation. We compared the outcomes of patients with newly diagnosed AF who received percutaneous LAAO or direct oral anticoagulants (DOAC) treatment, in a large population from a global federated health network (TriNetX). Methods Patients with AF treated with percutaneous LAAO were matched with those treated with DOAC between 1st December 2010 and 1st October 2018. Outcomes were all-cause mortality, ischaemic stroke and intracranial haemorrhage (ICH) at 5 years. Results We included 200 patients with AF, who received either LAAO or DOAC. The risk of all-cause mortality, ischaemic stroke and ICH at 5 years was not significantly different between the two groups (Risk Ratio [RR] for all-cause mortality: 1.52, 95% confidence interval (CI): 0.97- 2.38, RR for ischaemic stroke: 1.09, 95% CI: 0.51- 2.36, and RR for ICH: 1.0, 95% CI: 0.44- 2.30). Conclusion Patients newly diagnosed with AF, eligible for DOAC, showed similar 5-year risk of death, ischemic stroke, and ICH when comparing those who underwent percutaneous LAAO to those receiving DOAC. Future randomised controlled trials are needed to confirm the findings and advise changes in guidelines.

Is routine histopathological analysis of hemorrhoidectomy specimens necessary? A systematic review and meta-analysis.

BACKGROUND: Hemorrhoidectomy is a common procedure used to treat symptomatic hemorrhoids. However, the necessity and cost-effectiveness of routinely conducting histopathological analysis on excised tissue samples are uncertain. METHODS: A systematic review was conducted using MEDLINE and EMBASE up to December 2023 for studies assessing the histopathological outcomes of hemorrhoidectomy specimens. Meta-analysis was performed on articles with combinable results to determine the pooled proportions of cancer and anal intraepithelial neoplasia (AIN) using the random effects model. RESULTS: From 2974 initial search results, 12 studies were included in the review, with 48,365 resected specimens from hemorrhoidectomy. Among these, there were 11 retrospective studies and one prospective study. A meta-analysis of 11 studies revealed that the prevalence of anal cancer was low, at 0.13% (95% CI: 0.05%-0.31%). The prevalence of anal cancer and AIN combined was 1.16% (95% CI: 0.53%-2.52%). CONCLUSION: This literature review estimated the probability of malignancy detection in hemorrhoid specimens sent for histopathological evaluation. The low incidence of malignant findings implies that routine analysis of hemorrhoidectomy samples may not be cost-effective. However, existing studies have yet to establish definitive risk factors for abnormal histological diagnoses to aid in the selection of specimens for selective histopathology.

Association between frailty, long-term mortality and functional outcomes for older adults undergoing emergency laparotomy.

BACKGROUND: An increasing number of older patients are undergoing emergency laparotomy (EL). Frailty is thought to contribute to adverse outcomes in this group. The best method to assess frailty and impacts on long-term mortality and other important functional outcomes for older EL patients have not been fully explored. METHODS: A prospective multicenter study of older EL patients was conducted across four hospital sites in New Zealand from August 2017 to September 2022. The Clinical Frailty Scale (CFS) was used to measure frailty-defined as a CFS of ≥5. Primary outcomes were 30-day and one-year mortality. Secondary outcomes were postoperative morbidity, admission for rehabilitation, and increased care level on discharge. A multivariate logistic regression analysis was conducted, adjusting for age, sex, and ethnicity. RESULTS: A total of 629 participants were included. Frailty prevalence was 14.6%. Frail participants demonstrated higher 30-day and 1-year mortality-20.7% and 39.1%. Following adjustment, frailty was directly associated with a significantly increased risk of short- and long-term mortality (30-day aRR 2.6, 95% CI 1.5, 4.3, p = <0.001, 1-year aRR 2.0, 95% CI 1.5, 2.8, p < 0.001). Frailty was correlated with a 2-fold increased risk of admission for rehabilitation and propensity of being discharged to an increased level of care, complications, and readmission within 30 days. CONCLUSION: Frailty was associated with increased risk of postoperative mortality up to 1-year and other functional outcomes for older patients undergoing EL. Identification of frailty in older EL patients aids in patient-centered decision-making, which may lead to improvement in outcomes.

Smoking data quality of primary care practices in comparison with smoking data from the New Zealand Maori and Pacific abdominal aortic aneurysm screening programme: an observational study.

BACKGROUND: Quality smoking data is crucial for assessing smoking-related health risk and eligibility for interventions related to that risk. Smoking information collected in primary care practices (PCPs) is a major data source; however, little is known about the PCP smoking data quality. This project compared PCP smoking data to that collected in the Maori and Pacific Abdominal Aortic Aneurysm (AAA) screening programme. METHODS: A two stage review was conducted. In Stage 1, data quality was assessed by comparing the PCP smoking data recorded close to AAA screening episodes with the data collected from participants at the AAA screening session. Inter-rater reliability was analysed using Cohen's kappa scores. In Stage 2, an audit of longitudinal smoking status was conducted, of a subset of participants potentially misclassified in Stage 1. Data were compared in three groups: current smoker (smoke at least monthly), ex-smoker (stopped > 1 month ago) and never smoker (smoked < 100 cigarettes in lifetime). RESULTS: Of the 1841 people who underwent AAA screening, 1716 (93%) had PCP smoking information. Stage 1 PCP smoking data showed 82% concordance with the AAA data (adjusted kappa 0.76). Fewer current or ex-smokers were recorded in PCP data. In the Stage 2 analysis of discordant and missing data (N = 313), 212 were enrolled in the 29 participating PCPs, and of these 13% were deceased and 41% had changed PCP. Of the 93 participants still enrolled in the participating PCPs, smoking status had been updated for 43%. Data on quantity, duration, or quit date of smoking were largely missing in PCP records. The AAA data of ex-smokers who were classified as never smokers in the Stage 2 PCP data (N = 27) showed a median smoking cessation duration of 32 years (range 0-50 years), with 85% (N = 23) having quit more than 15 years ago. CONCLUSIONS: PCP smoking data quality compared with the AAA data is consistent with international findings. PCP data captured fewer current and ex-smokers, suggesting ongoing improvement is important. Intervention programmes based on smoking status should consider complementary mechanisms to ensure eligible individuals are not missed from programme invitation.

Factors associated with low fruit and vegetable consumption among people with severe mental ill health.

Severe mental ill health (SMI) is associated with excess mortality, and poor diet is one associated modifiable risk factor. This study investigated factors associated with low consumption of fruit and vegetables among people with SMI (N = 9914). A total of 8.4% of participants ate no portions per day, while only 15% ate 5 + portions. Individuals who never consumed fruit and vegetables or ate < 5 portions per day were more likely to be male, younger than 65, unemployed, experience poorer general health, or perceive health as unimportant. Poor diet is common among people with SMI and tailored dietary improvement interventions are required.

Experiences of emotional eating in an Acceptance and Commitment Therapy based weight management intervention (SWiM): A qualitative study.

BACKGROUND: Emotional eating is a barrier to weight management. Interventions based on Acceptance and Commitment Therapy (ACT) promote the acceptance of uncomfortable feelings, which can reduce the urge to use food as a coping mechanism. We aimed to explore how participants of an ACT-based weight management intervention (WMI) experience emotional eating and relevant intervention content. METHODS: We conducted semi-structured telephone interviews with participants of a digital ACT-based guided self-help WMI. Fifteen participants were purposefully selected to represent a range of demographic characteristics and emotional eating scores. We used reflexive thematic analysis to explore experiences of emotional eating. RESULTS: We generated five themes. Participants improved emotional eating by disconnecting emotions from behaviours though increased self-awareness (theme 1) and by implementing alternative coping strategies, including preparation, substitution, and acceptance (theme 2). Most participants maintained improvements in emotional eating over time but wished for more opportunities to re-engage with intervention content, including more immediate support in triggering situations (theme 3). Participants who struggled to engage with emotional eating related intervention content often displayed an external locus of control over emotional eating triggers (theme 4). The perceived usefulness of the intervention depended on participants' prior experiences of emotional eating, and was thought insufficient for participants with complex emotional experiences (theme 5). DISCUSSION: This ACT-based WMI helped participants with emotional eating by improving self-awareness and teaching alternative coping strategies. Intervention developers may consider adding ongoing forms of intervention that provide both real-time and long-term support. Additionally, a better understanding of how to support people with an external locus of control and people with complex experiences of emotional eating is needed. Future research may explore ways of personalising WMIs based on participants' emotional needs.

microRNA-146a modulates behavioural activity, neuroinflammation, and oxidative stress in adult mice.

Small non-coding miRNA act as key regulators of several physiological processes due to their ability to interact with numerous target mRNA within a network. Whilst several miRNA can act in concert to regulate target mRNA expression, miR-146a has emerged as a critical modulator of inflammation by targeting key upstream signalling proteins of the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway and reductions in this miRNA have been observed in several neurological and neurodegenerative disorders. However, a targeted assessment of behaviour and neural tissues following the loss of miR-146a has not been documented. In this study, we examined the behavioural and neuroinflammatory phenotype of mice lacking miR-146a to determine the role of this miRNA in neurological function. Adult miR-146a-/- mice displayed no overt developmental phenotype with the exception of enlarged spleens. Behavioural testing revealed a mild but significant reduction in exploratory locomotor activity and increase in anxiety-like behaviour, with no changes in short-term spatial memory, fear conditioning, or sensorimotor gating. In the brain, the lack of miR-146a resulted in a significant compensatory miR-155 expression with no significant changes in expression of the target Interleukin 1 Receptor Associated Kinase (Irak) gene family. Despite these effects on upstream NF-κB mediators, downstream expression of cytokine and chemokine messengers was significantly elevated in miR-146a-/- mice compared to wild-type controls. Moreover, this increase in inflammatory cytokines was observed alongside an induction of oxidative stress, driven in part by nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, and included reduced thiol antioxidant concentrations and increased oxidised protein carbonyl concentrations. In female miR-146a mice, this increase in oxidative stress resulted in an increased expression of superoxide dismutase 1 (SOD1). Together, this suggests miR-146a plays a key role in regulating inflammation even in the absence of inflammatory stimuli and reduced levels of this miRNA have the capacity to induce limited behavioural effects whilst exacerbating both inflammation and oxidative stress in the brain.

The Prevalence and Management of Atrial Fibrillation in New Zealand Maori Detected through an Abdominal Aortic Aneurysm Screening Program.

BACKGROUND: Atrial fibrillation (AF) screening was incorporated into an abdominal aortic aneurysm screening (AAA) program for New Zealand (NZ) Maori. METHODS: AF screening was performed as an adjunct to AAA screening of Maori men aged 60-74 years and women aged 65-74 years registered with primary health care practices in Auckland, NZ. Pre-existing AF was determined through coded diagnoses or medications in the participant's primary care record. Subsequent audit of the record assessed accuracy of pre-screening coding, medication use and clinical follow-up. RESULTS: Among 1,933 people successfully screened, the prevalence of AF was 144 (7.4%), of which 46 (2.4% of the cohort) were patients without AF coded in the medical record. More than half of these were revealed to be known AF but that was not coded. Thus, the true prevalence of newly detected AF was 1.1% (n=21). An additional 48 (2.5%) of the cohort had been coded as AF but were not in AF at the time of screening. Among the 19 at-risk screen-detected people with AF, 10 started appropriate anticoagulation therapy within 6 months. Of the nine patients who did not commence anticoagulation therapy, five had a subsequent adverse clinical outcome in the follow-up period, including one with ischaemic stroke; two had contraindications to anticoagulants. Among those with previously diagnosed AF, the proportion receiving anticoagulation therapy rose from 57% pre-screening to 83% at 6 months post-screening (p<0.0001); among newly diagnosed AF the proportion rose from 0% to 53% (p<0.01). CONCLUSIONS: AF screening is a feasible low-cost adjunct to AAA screening with potential to reduce ethnic inequities in stroke incidence. However, effective measures are needed to ensure that high-risk newly diagnosed AF is managed according to best practice guidelines.

The mechanism of Pseudomonas aeruginosa outer membrane vesicle biogenesis determines their protein composition.

Gram-negative bacteria produce outer membrane vesicles (OMVs) and contain bacterial cargo including nucleic acids and proteins. The proteome of OMVs can be altered by various factors including bacterial growth stage, growth conditions, and environmental factors. However, it is currently unknown if the mechanism of OMV biogenesis can determine their proteome. In this study, we examined whether the mechanisms of OMV biogenesis influenced the production and protein composition of Pseudomonas aeruginosa OMVs. OMVs were isolated from three P. aeruginosa strains that produced OMVs either by budding alone, by explosive cell lysis, or by both budding and explosive cell lysis. We identified that the mechanism of OMV biogenesis dictated OMV quantity. Furthermore, a global proteomic analysis comparing the proteome of OMVs to their parent bacteria showed significant differences in the identification of proteins in bacteria and OMVs. Finally, we determined that the mechanism of OMV biogenesis influenced the protein composition of OMVs, as OMVs released by distinct mechanisms of biogenesis differed significantly from one another in their proteome and functional enrichment analysis. Overall, our findings reveal that the mechanism of OMV biogenesis is a main factor that determines the OMV proteome which may affect their subsequent biological functions.