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Aims: Point-of-care (POC) high-sensitivity troponin (hs-cTn) assays within a clinical pathway may safely reduce length of stay (LoS) for patients presenting to the emergency department (ED) with possible acute myocardial infarction (AMI). In this early report, we present the first evaluation of a POC hs-cTn in real-life care., Methods and Results: In adult patients presenting to ED investigated for possible AMI, we compared the LoS in patients assessed with a troponin in the 8 weeks before (usual-care phase) and the 8 weeks following introduction of the Siemens Atellica VTLi POC hs-cTnI for decision-making (intervention phase). The VTLi replaced the laboratory (Beckman Coulter) assay as the default hs-cTn test within the clinical pathway. This was the only change to the pathway process. The safety outcome was first event AMI or cardiac death within 30 days. There were 2376 presentations in the usual-care phase with 188 individuals with AMI and 2392 in the intervention phase with 198 AMI. In the intervention phase, there was a mean (95% CI) reduction in LoS of 32 min (22-41 min) compared with the usual-care phase. This represents 21.4 fewer patient-hours in the ED each day (1196 in the 8-week period). In both phases, the pathway correctly identified all cases of AMI at index attendance. There were four follow-up events (two usual-care, two intervention) within 30 days., Conclusion: The deployment of a hs-cTn POC analyser into a large ED safely reduced length of stay. If translatable to other EDs, this could represent an important advancement to patient care., Trial Registration: Australia New Zealand Clinical Trials Registry, No. ACTRN12619001189112., Competing Interests: Conflict of interest: J.W.P. has received fees for statistical consulting from Siemens Healthineers, Radiometer, OrthoQuidel, and Upstream Medical Technologies and has non-disclosure agreements with Abbott and Roche. M.P.T. has received honoraria, consultancy fees, and research funding from Abbott, Alere, Beckman, QuidelOrtho, Radiometer, Roche, and Siemens Healthineers. No other author has conflicts of interest to declare., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)

Objective: To evaluate gender authorship trends in the official journal of the Australasian College for Emergency Medicine (ACEM), Emergency Medicine Australasia (EMA)., Methods: A bibliometric review of author gender in EMA during the 10-year period 2013-2022. The gender of first/last authors were determined by www.genderize.io, or a manual internet search where gender was not determined with at least 90% certainty. Descriptive statistics were used with percentages of women as first and last author compared to current percentages of ACEM Fellows (FACEMs) who identify as women., Results: The final analysis included 1703 articles. Women accounted for 27.4% fewer authors than men (36.3% vs 63.7%). Women were outnumbered by men by 20.0% among first authors (40% vs 60%), and 36.2% (31.9% vs 68.1%) for last authors. When the last author was a woman, there was a similar rate of women (49.2%) and men (50.8%) as first authors. However, when the last author was a man, first authors were 37.1% women versus 62.9% men. If the last author was a woman, there was a 60% greater probability that the first author was also a woman (odds ratio 1.6, 95% CI 1.3-2.1). First authorship rate by women was equal to or exceeds the proportion of women FACEMs, however, last authorship by women still lags behind., Conclusion: The emergency medicine community in Australasia must continue to tackle existing gender disparities which exist in our specialty. A creative and active strategy on the part of publishers, editors, academics and authors is needed to redress this balance., (© 2024 Australasian College for Emergency Medicine.)

Bacterial membranes are complex and dynamic, arising from an array of evolutionary pressures. One enzyme that alters membrane compositions through covalent lipid modification is MprF. We recently identified that Streptococcus agalactiae MprF synthesizes lysyl-phosphatidylglycerol (Lys-PG) from anionic PG, and a novel cationic lipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), from neutral glycolipid Glc-DAG. This unexpected result prompted us to investigate whether Lys-Glc-DAG occurs in other MprF-containing bacteria, and whether other novel MprF products exist. Here, we studied protein sequence features determining MprF substrate specificity. First, pairwise analyses identified several streptococcal MprFs synthesizing Lys-Glc-DAG. Second, a restricted Boltzmann machine-guided approach led us to discover an entirely new substrate for MprF in Enterococcus , diglucosyl-diacylglycerol (Glc 2 -DAG), and an expanded set of organisms that modify glycolipid substrates using MprF. Overall, we combined the wealth of available sequence data with machine learning to model evolutionary constraints on MprF sequences across the bacterial domain, thereby identifying a novel cationic lipid., Competing Interests: PC, JM, AU, LJ, YW, ZG, FM, KP No competing interests declared, (© 2024, Christensen, Martin et al.)

Bacterial cell surface components such as lipoteichoic acids (LTAs) play critical roles in host-microbe interactions and alter host responses based on their chemical structures. Mitis group streptococci have commensal and pathogenic interactions with the human host and produce Type IV LTAs that are slightly different in chemical structures between species. To reveal the molecular bases for the intricate interactions between MGS and human hosts, a detailed understanding of the structure and biosynthetic process of MGS LTAs is needed. In this study, we used genomic and lipidomic techniques to elucidate the biosynthetic processes of Type IV LTA and its associated glycolipid anchors, monohexosyl-diacylglycerol and dihexosyl-diacyglycerol, in the infectious endocarditis isolate Streptococcus sp. strain 1643. Through establishing a murine sepsis model, we validated the essentiality of these glycolipids in the full virulence of S. mitis . Additionally, we found that these glycolipids play an important role in protecting the bacteria from antimicrobials. Overall, results obtained through this study both confirm and dispute aspects of the existing model of glycolipids biosynthesis, provide insights into the fundamental roles of bacterial glycolipids, as well as suggest the potential of targeting glycolipids for developing antimicrobial therapeutics.

Group B Streptococcus (GBS) is a Gram-positive pathobiont that commonly colonizes the gastrointestinal and lower female genital tracts but can cause sepsis and pneumonia in newborns and is a leading cause of neonatal meningitis. Despite the resulting disease severity, the pathogenesis of GBS is not completely understood, especially during the early phases of infection. To investigate GBS factors necessary for blood stream survival, we performed a transposon (Tn) mutant screen in our bacteremia infection model using a GBS mariner transposon mutant library previously developed by our group. We identified significantly underrepresented mutations in 539 genes that contribute to survival in the blood, including those encoding known virulence factors such as capsule, the β-hemolysin, and inorganic metal ion transport systems. Most of the underrepresented genes have not been previously characterized or studied in GBS, including gloA and gloB, which are homologs for genes involved in methylglyoxal (MG) detoxification. MG is a byproduct of glycolysis and a highly reactive toxic aldehyde that is elevated in immune cells during infection. Here, we observed MG sensitivity across multiple GBS isolates and confirm that gloA contributes to MG tolerance and invasive GBS infection. We show specifically that gloA contributes to GBS survival in the presence of neutrophils and depleting neutrophils in mice abrogates the decreased survival and infection of the gloA mutant. The requirement of the glyoxalase pathway during GBS infection suggests that MG detoxification is important for bacterial survival during host-pathogen interactions.

Bacterial membranes are complex and dynamic, arising from an array of evolutionary pressures. One enzyme that alters membrane compositions through covalent lipid modification is MprF. We recently identified that Streptococcus agalactiae MprF synthesizes lysyl-phosphatidylglycerol (Lys-PG) from anionic PG, and a novel cationic lipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), from neutral glycolipid Glc-DAG. This unexpected result prompted us to investigate whether Lys-Glc-DAG occurs in other MprF-containing bacteria, and whether other novel MprF products exist. Here, we studied protein sequence features determining MprF substrate specificity. First, pairwise analyses identified several streptococ-cal MprFs synthesizing Lys-Glc-DAG. Second, a restricted Boltzmann machine-guided approach led us to discover an entirely new substrate for MprF in Enterococcus , diglucosyl-diacylglycerol (Glc 2 -DAG), and an expanded set of organisms that modify glycolipid substrates using MprF. Overall, we combined the wealth of available sequence data with machine learning to model evolutionary constraints on MprF sequences across the bacterial domain, thereby identifying a novel cationic lipid.

Aim: To assess the equity of care of patients with non-traumatic dental presentations (NTDP) to Christchurch Emergency Department (ED) in Aotearoa New Zealand., Methods: This retrospective observational study reviews NTDP to Christchurch ED over a 2-year period (2018-2020). ED and hospital outcomes were compared for Māori, Pacific peoples and NZ Europeans. Results are interpreted utilising Te Ao Māori principles and discussed referencing a Kaupapa Māori framework., Results: There were a total of 2,034 NTDPs, with Māori (27.0%) and Pacific peoples (6.9%) being over-represented compared to local population estimates (9.4% and 3.2% respectively). Māori experienced shorter wait times (45 minutes, 95% CI 22-86) compared to NZ Europeans (56 minutes, 95% CI 24-97) and Pacific peoples (54 minutes, 95% CI 23-97). Māori had the highest age-standardised incidence of admission, but shorter hospital length of stay (0.9 days, IQR 0.4-2.3) compared to Pacific peoples (3.8 days, IQR 1.8-3.9) and NZ Europeans (2.0 days, IQR 1.0-3.7)., Conclusion: This is the first paper to employ a Kaupapa Māori approach examining NTDP patients presenting to the ED. While outcome measures were largely positive, differences in demographic variables indicate upstream failures, specifically barriers to accessing primary oral healthcare and a paucity of Kaupapa Māori initiatives. Further action and accountability are required to provide high-quality, equitable care for Māori., Competing Interests: Nil., (© PMA.)

Streptococcus agalactiae [group B Streptococcus (GBS)] is a leading cause of neonatal meningitis, with late-onset disease (LOD) occurring after gastrointestinal tract colonization in infants. Bacterial membrane lipids are essential for host-pathogen interactions, and the functions of glycolipids are yet to be fully elucidated. GBS synthesizes three major glycolipids: glucosyl-diacylglycerol (Glc-DAG), diglucosyl-DAG (Glc 2 -DAG), and lysyl-Glc-DAG (Lys-Glc-DAG). Here, we identify the enzyme, IagB, as responsible for biosynthesis of Glc-DAG, the precursor for the two other glycolipids in GBS. To examine the collective role of glycolipids to GBS virulence, we adapted a murine model of neonatal meningitis to simulate LOD. The GBS∆ iagB mutant traversed the gut-epithelial barrier comparable to wild type but was severely attenuated in bloodstream survival, resulting in decreased bacterial loads in the brain. The GBS∆ iagB mutant was more susceptible to neutrophil killing and membrane targeting by host antimicrobial peptides. This work reveals an unexplored function of GBS glycolipids with their ability to protect the bacterial cell from host antimicrobial killing.

Aims: Emergency departments (EDs) around the world are increasingly overcrowded, which is associated with significant patient harm. Alcohol use is a known contributor to ED overcrowding. This study aimed to assess trends in the characteristics of alcohol-related ED presentations over time., Methods: A cross-sectional observational study of Christchurch ED attendances during 3-week waves of data collection in November-December 2013, 2017 and 2022 was conducted. Potential participants were those patients attending the Christchurch Hospital ED who had ingested alcohol in the 4 hours prior to arrival, and/or the presentation was thought to be related to alcohol. Those who consented to take part were interviewed to examine amount and source of alcohol., Results: There has been a change in the age profile towards a greater proportion of older patients attending the ED with alcohol-related issues. In 2022, a greater proportion of alcohol was purchased from on-licence venues compared to previous years, although off-licence alcohol purchase and consumption in private locations remained the most common., Conclusion: Alcohol use and harm places a significant, yet preventable, burden on EDs and the wider healthcare system. Implementation of evidence-based alcohol policies is urgently needed to reduce the impact of alcohol in the ED and improve the health of communities., Competing Interests: None to declare., (© PMA.)

Objective: Youth mental health is a growing issue, which can be worsened by alcohol and other drug (AOD) use. The present study aimed to characterise the association of AOD use in youth presenting to an ED with a mental health crisis., Methods: A retrospective observational study of paediatric patients presenting with mental health concerns to a tertiary ED in New Zealand in 2019-2020, with an examination of use of alcohol or other drugs before presentation., Results: There were 842 ED presentations, made up of 491 unique individuals, examined from the 2-year period. Overdose (63.1%) was the most common reason for presentation, with 39.9% of overdoses involving prescription-only medications, 36.7% over-the-counter, and 20.0% a combination. Seventy-four (8.8%) presentations had documented use of alcohol or other drugs (excluding those taken in overdose) before arrival, with alcohol (51 presentations), followed by cannabis (19 presentations), being the most commonly recorded drugs used. Concurrent AOD use was not associated with any significant difference in triage, length of stay or admission status., Conclusion: In New Zealand, it is not legal to sell alcohol to persons under 18 years; however, this was the most commonly identified drug impacting on youth mental health presentations. There is a known association between alcohol use and adverse mental health symptoms; therefore, efforts to decrease access to alcohol in this age group must continue, and harm reduction interventions to reduce clinically significant overdoses recommended., (© 2023 The Authors. Emergency Medicine Australasia published by John Wiley & Sons Australia, Ltd on behalf of Australasian College for Emergency Medicine.)

Objective: To identify factors associated with death secondary to haemorrhage following major trauma., Methods: A retrospective case-control study was conducted on data from adult major trauma patients attending Christchurch Hospital ED between 1 June 2016 and 1 June 2020. Cases (those who died due to haemorrhage or multiple organ failure [MOF]), were matched to controls (those who survived) in a 1:5 ratio from the Canterbury District Health Board major trauma database. A multivariate analysis was used to identify potential risk factors for death due to haemorrhage., Results: One thousand, five hundred and forty major trauma patients were admitted to Christchurch Hospital or died in ED during the study period. Of them, 140 (9.1%) died from any cause, most attributed to a central nervous system cause of death; 19 (1.2%) died from haemorrhage or MOF. After controlling for age and injury severity, having a lower temperature on arrival in ED was a significant modifiable risk factor for death. Additionally, intubation prior to hospital, increased base deficit, lower initial haemoglobin and lower Glasgow Coma Scale were risk factors associated with death., Conclusions: The present study reaffirms previous literature that lower body temperature on presentation to hospital is a significant potentially modifiable variable in predicting death following major trauma. Further studies should investigate whether all pre-hospital services have key performance indicators (KPIs) for temperature management, and causes for failure to reach these. Our findings should promote development and tracking of such KPIs where they do not already exist., (© 2023 The Authors. Emergency Medicine Australasia published by John Wiley & Sons Australia, Ltd on behalf of Australasian College for Emergency Medicine.)

Objective: Atrial fibrillation/flutter (AF/AFL) accounts for high rates of ED presentations and hospital admissions. There is increasing evidence to suggest that delaying cardioversion for acute uncomplicated AF is safe, and that many patients will spontaneously revert to sinus rhythm (SR). We conducted a before-and-after evaluation of AF/AFL management after a change in ED pathway using a conservative 'rate-and-wait' approach, incorporating next working day outpatient clinic follow-up and delayed cardioversion if required., Methods: We performed a before-and-after retrospective cohort study examining outcomes for patients who presented to the ED in Christchurch, New Zealand, with acute uncomplicated AF/AFL in the 1-year period before and after the implementation of a new conservative management pathway., Results: A total of 360 patients were included in the study (182 'Pre-pathway' vs 178 'Post-Pathway'). Compared to the pre-pathway cohort, those managed under the new pathway had an 81.2% reduction in ED cardioversions (n = 32 vs n = 6), and 50.7% reduction in all cardioversions (n = 65 vs n = 32). There was a 31.6% reduction in admissions from ED (n = 54 vs n = 79). ED length of stay (3.9 h vs 3.8 h, net difference -0.1 h, 95% confidence interval [CI] -0.6 to 0.3), 1-year ED AF representation (32.4% vs 26.4%, net difference -6.0% [95% CI -16.0% to 3.9%]), 1-year ED ischaemic stroke presentation (2.2% in both groups) and 7-day all-cause mortality rates (hazard ratio 1.05 [95% CI 0.6 to 1.9]) were all similar., Conclusions: Using a conservative 'rate-and-wait' strategy with early follow-up for patients presenting to ED with AF/AFL can safely reduce unnecessary cardioversions and avoidable hospitalisations., (© 2023 The Authors. Emergency Medicine Australasia published by John Wiley & Sons Australia, Ltd on behalf of Australasian College for Emergency Medicine.)

The arachnoid barrier, a component of the blood-cerebrospinal fluid barrier (B-CSFB) in the meninges, is composed of epithelial-like, tight-junction-expressing cells. Unlike other central nervous system (CNS) barriers, its' developmental mechanisms and timing are largely unknown. Here, we show that mouse arachnoid barrier cell specification requires the repression of Wnt-β-catenin signaling and that constitutively active β-catenin can prevent its formation. We also show that the arachnoid barrier is functional prenatally and, in its absence, a small molecular weight tracer and the bacterium group B Streptococcus can cross into the CNS following peripheral injection. Acquisition of barrier properties prenatally coincides with the junctional localization of Claudin 11, and increased E-cadherin and maturation continues after birth, where postnatal expansion is marked by proliferation and re-organization of junctional domains. This work identifies fundamental mechanisms that drive arachnoid barrier formation, highlights arachnoid barrier fetal functions, and provides novel tools for future studies on CNS barrier development., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Competing Interests: The authors have declared that no competing interests exists.

The viridans group streptococci (VGS) are a large consortium of commensal streptococci that colonize the human body. Many species within this group are opportunistic pathogens causing bacteremia and infective endocarditis (IE), yet little is known about why some strains cause invasive disease. Identification of virulence determinants is complicated by the difficulty of distinguishing between the closely related species of this group. Here, we analyzed genomic data from VGS that were isolated from blood cultures in patients with invasive infections and oral swabs of healthy volunteers and then determined the best-performing methods for species identification. Using whole-genome sequence data, we characterized the population structure of a diverse sample of Streptococcus oralis isolates and found evidence of frequent recombination. We used multiple genome-wide association study tools to identify candidate determinants of invasiveness. These tools gave consistent results, leading to the discovery of a single synonymous single nucleotide polymorphism (SNP) that was significantly associated with invasiveness. This SNP was within a previously undescribed gene that was conserved across the majority of VGS species. Using the growth in the presence of human serum and a simulated infective endocarditis vegetation model, we were unable to identify a phenotype for the enriched allele in laboratory assays, suggesting a phenotype may be specific to natural infection. These data highlighted the power of analyzing natural populations for gaining insight into pathogenicity, particularly for organisms with complex population structures like the VGS. IMPORTANCE The viridians group streptococci (VGS) are a large collection of closely related commensal streptococci, with many being opportunistic pathogens causing invasive diseases, such as bacteremia and infective endocarditis. Little is known about virulence determinants in these species, and there is a distinct lack of genomic information available for the VGS. In this study, we collected VGS isolates from invasive infections and healthy volunteers and performed whole-genome sequencing for a suite of downstream analyses. We focused on a diverse sample of Streptococcus oralis genomes and identified high rates of recombination in the population as well as a single genome variant highly enriched in invasive isolates. The variant lies within a previously uncharacterized gene, nrdM , which shared homology with the anaerobic ribonucleoside triphosphate reductase, nrdD , and was highly conserved among VGS. This work increased our knowledge of VGS genomics and indicated that differences in virulence potential among S. oralis isolates were, at least in part, genetically determined.

Aims: To examine reported levels of violence and aggression within a tertiary level emergency department in New Zealand, and to compare incident reporting within a dedicated yearly audit period to standard organisational reporting procedures., Method: A prospective, longitudinal cohort study involving repeated yearly audits of violence and aggression reported by emergency department staff from 2014-2020., Results: Episodes of violence and aggression were reported at high levels during audit months compared to standard reporting, suggesting current systems do not accurately reflect the presence of violence and aggression. Levels of reported violence and aggression remained relatively static over a seven-year period, despite increasing emergency department attendances. Most events reported involved verbal abuse from patients, and occurred on weekend and night shifts. A number of potentially contributing factors were identified., Conclusions: Persistently higher levels of violence and aggression were reported during the targeted audit months, while reporting via the organisation's formal system during the intervening months remained at low levels. Further research is essential to monitor trends, assess the effectiveness of interventions to improve reporting, modify factors contributing to violence and aggression, and to address the impact on staff and bystanders affected in emergency departments., Competing Interests: Nil.

Bacterial membrane lipids are critical for membrane bilayer formation, cell division, protein localization, stress responses, and pathogenesis. Despite their critical roles, membrane lipids have not been fully elucidated for many pathogens. Here, we report the discovery of a novel cationic glycolipid, lysyl-glucosyl-diacylglycerol (Lys-Glc-DAG), which is synthesized in high abundance by the bacterium Streptococcus agalactiae (Group B Streptococcus, GBS). To our knowledge, Lys-Glc-DAG is more positively charged than any other known lipids. Lys-Glc-DAG carries 2 positive net charges per molecule, distinct from the widely described lysylated phospholipid lysyl-phosphatidylglycerol (Lys-PG) that carries one positive net charge due to the presence of a negatively charged phosphate moiety. We use normal phase liquid chromatography (NPLC) coupled with electrospray ionization (ESI) high-resolution tandem mass spectrometry (HRMS/MS) and genetic approaches to determine that Lys-Glc-DAG is synthesized by the enzyme MprF in GBS, which covalently modifies the neutral glycolipid Glc-DAG with the cationic amino acid lysine. GBS is a leading cause of neonatal meningitis, which requires traversal of the endothelial blood-brain barrier (BBB). We demonstrate that GBS strains lacking mprF exhibit a significant decrease in the ability to invade BBB endothelial cells. Further, mice challenged with a GBSΔmprF mutant developed bacteremia comparably to wild-type (WT) infected mice yet had less recovered bacteria from brain tissue and a lower incidence of meningitis. Thus, our data suggest that Lys-Glc-DAG may contribute to bacterial uptake into host cells and disease progression. Importantly, our discovery provides a platform for further study of cationic lipids at the host-pathogen interface., Competing Interests: The authors have declared that no competing interests exist

Aim: Atrial fibrillation/flutter (AF/AFL) is associated with high rates of emergency department (ED) visits and acute hospitalisation. A recently established multidisciplinary acute AF treatment pathway seeks to avoid hospital admissions by early discharge of haemodynamically stable, low risk patients from the ED with next-working-day return to a ward-based AF clinic for further assessment. We conducted a preliminary analysis of the clinical outcomes of this pathway., Methods: We retrospectively reviewed clinical records of all patients assessed at the AF clinic at Christchurch Hospital, New Zealand, over a 12-month period. Data related to presentation, patient characteristics, treatment, and 12-month outcomes were analysed., Results: A total of 143 patients (median age 65, interquartile range: 57-74 years, 59% male, 87% European) were assessed. Of these, 87 (60.8%) presented with their first episode of AF/AFL. Spontaneous cardioversion occurred in 41% at ED discharge, and this increased to 73% at AF clinic review. Electrical cardioversion was subsequently performed in 16 patients (11.2%), and 16 (11.2%) ultimately required hospital admission (eight to facilitate electrical cardioversion). At a median of 1 day, 83.9% were discharged from the AF clinic in sinus rhythm. During 12-month follow-up, there were 25 AF-related hospitalisations (20 patients, 14%) and one patient underwent electrical cardioversion; additionally, one patient had had a stroke and eight had bleeding complications giving a combined outcome rate of 6.3%., Conclusion: Utilising a rate-control strategy with ED discharge and early return to a dedicated AF clinic can safely prevent the majority of hospitalisations, avert unnecessary procedures, and facilitate longitudinal care., (Copyright © 2021 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Aim: To describe the variation in volumes and types of paediatric presentations to a tertiary emergency department in New Zealand during the national level 4 lockdown for COVID-19., Methods: A retrospective, comparative cohort study in Christchurch Hospital Emergency Department, New Zealand., Results: There was a 37% reduction in all emergency presentations during the 33-day lockdown period. Paediatric presentations reduced significantly more than non-paediatric presentations (53% paediatric vs. 34% non-paediatric, P < 0.00001). The decrease in both overall and paediatric presentations was significantly different than similar periods in 2019 and 2018 (P < 0.00001). The proportion of New Zealand European paediatric presentations during lockdown increased by 6.09% (P = 0.01), while Pacific peoples decreased by 3.36% (P = 0.005). The proportion of <1-year-old presentations increased by 5.56% (P = 0.001), while 11-15 years decreased by 7.91% (P = 0.0001). Respiratory-related paediatric presentations decreased by 30% and proportional decreased by 4.92% (P = 0.001)., Conclusion: This study has identified a significant reduction in paediatric presentations to a tertiary emergency department in New Zealand during the national Alert Level 4 Lockdown for COVID-19. The proportional increase in the <1-year-old group may suggest a greater need for community-based child health services during the COVID-19 pandemic. Mental health support services may also need to adapt and expand to provide adequate psychological support for children during this crisis. Recognising the needs of these vulnerable groups will be critical during the ongoing COVID-19 pandemic in addition to informing response plans for similar events in the future., (© 2021 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).)

Streptococcus pneumoniae , S. pyogenes (Group A Streptococcus ; GAS) and S. agalactiae (Group B Streptococcus ; GBS) are major aetiological agents of diseases in humans. The cellular membrane, a crucial site in host-pathogen interactions, is poorly characterized in streptococci. Moreover, little is known about whether or how environmental conditions influence their lipid compositions. Using normal phase liquid chromatography coupled with electrospray ionization MS, we characterized the phospholipids and glycolipids of S. pneumoniae , GAS and GBS in routine undefined laboratory medium, streptococcal defined medium and, in order to mimic the host environment, defined medium supplemented with human serum. In human serum-supplemented medium, all three streptococcal species synthesize phosphatidylcholine (PC), a zwitterionic phospholipid commonly found in eukaryotes but relatively rare in bacteria. We previously reported that S. pneumoniae utilizes the glycerophosphocholine (GPC) biosynthetic pathway to synthesize PC. Through substrate tracing experiments, we confirm that GAS and GBS scavenge lysoPC, a major metabolite in human serum, thereby using an abbreviated GPC pathway for PC biosynthesis. Furthermore, we found that plasmanyl-PC is uniquely present in the GBS membrane during growth with human serum, suggesting GBS possesses unusual membrane biochemical or biophysical properties. In summary, we report cellular lipid remodelling by the major pathogenic streptococci in response to metabolites present in human serum.

Objective: To describe mental health presentations to a tertiary ED in New Zealand during a national COVID-19 lockdown., Methods: A retrospective, comparative cohort study in Christchurch Hospital, New Zealand., Results: There was a 3510 (37%)-patient decrease in all presentations to Christchurch Hospital ED during the 5-week COVID-19 lockdown period from 26 March 2020 to 28 April 2020, compared to a 111 (1.2%)-patient decrease in the same time period in the previous year (P < 0.00001). There is usually a seasonal reduction in mental health attendances at this time of year compared to the weeks before. In 2019, there was a 49 (9.8%)-patient reduction in mental health presentations, whereas in 2020 there was a 193 (34%)-patient reduction (P < 0.001). In 2020, the proportion of mental health attendances compared to all ED attendances during the 5-week lockdown period was similar to the 5-week pre-lockdown period (564/9460 vs 371/5950, P = 0.48). The proportion of mental health patients presenting due to overdose increased by 6.5% (158/564 vs 128/371, P = 0.035); those due to self-harm increased by 3.5% (35/564 vs 36/371, P = 0.049). The proportion of mental health presentations due to anxiety, depression and other non-self-harm/overdose complaints decreased by 10% (371/564 vs 207/371, P = 0.002). The proportion of overdoses of paracetamol and ibuprofen increased by 13.4% during lockdown (22/158 vs 35/128, P = 0.005)., Conclusions: During the COVID-19 lockdown, both overall ED presentations as well as mental health-related presentations decreased. There was a relative increase in overdoses and self-harm, particularly involving paracetamol and ibuprofen., (© 2020 Australasian College for Emergency Medicine.)

Lipoteichoic acid (LTA) is a Gram-positive bacterial cell surface polymer that participates in host-microbe interactions. It was previously reported that the major human pathogen Streptococcus pneumoniae and the closely related oral commensals S. mitis and S. oralis produce type IV LTAs. Herein, using liquid chromatography/mass spectrometry-based lipidomic analysis, we found that in addition to type IV LTA biosynthetic precursors, S. mitis , S. oralis , and S. pneumoniae also produce glycerophosphate (Gro-P)-linked dihexosyl (DH)-diacylglycerol (DAG), which is a biosynthetic precursor of type I LTA. cdsA and pgsA mutants produce DHDAG but lack (Gro-P)-DHDAG, indicating that the Gro-P moiety is derived from phosphatidylglycerol (PG), whose biosynthesis requires these genes. S. mitis , but not S. pneumoniae or S. oralis , encodes an ortholog of the PG-dependent type I LTA synthase, ltaS By heterologous expression analyses, we confirmed that S. mitis ltaS confers poly(Gro-P) synthesis in both Escherichia coli and Staphylococcus aureus and that S. mitis ltaS can rescue the growth defect of an S. aureus ltaS mutant. However, we do not detect a poly(Gro-P) polymer in S. mitis using an anti-type I LTA antibody. Moreover, Gro-P-linked DHDAG is still synthesized by an S. mitis ltaS mutant, demonstrating that S. mitis LtaS does not catalyze Gro-P transfer to DHDAG. Finally, an S. mitis ltaS mutant has increased sensitivity to human serum, demonstrating that ltaS confers a beneficial but currently undefined function in S. mitis Overall, our results demonstrate that S. mitis , S. pneumoniae , and S. oralis produce a Gro-P-linked glycolipid via a PG-dependent, ltaS -independent mechanism. IMPORTANCE The cell wall is a critical structural component of bacterial cells that confers important physiological functions. For pathogens, it is a site of host-pathogen interactions. In this work, we analyze the glycolipids synthesized by the mitis group streptococcal species, S. pneumoniae , S. oralis , and S. mitis We find that all produce the glycolipid, glycerophosphate (Gro-P)-linked dihexosyl (DH)-diacylglycerol (DAG), which is a precursor for the cell wall polymer type I lipoteichoic acid in other bacteria. We investigate whether the known enzyme for type I LTA synthesis, LtaS, plays a role in synthesizing this molecule in S. mitis Our results indicate that a novel mechanism is responsible. Our results are significant because they identify a novel feature of S. pneumoniae , S. oralis , and S. mitis glycolipid biology., (Copyright © 2021 Wei et al.)

The mitis group streptococci include the major human pathogen Streptococcus pneumoniae and the opportunistic pathogens Streptococcus mitis and Streptococcus oralis , which are human oral cavity colonizers and agents of bacteremia and infective endocarditis in immunocompromised patients. Bacterial membrane lipids play crucial roles in microbe-host interactions; for many pathogens, however, the composition of the membrane is poorly understood. In this study, we characterized the lipidomes of selected species of mitis group streptococci and investigated the mechanistic basis for biosynthesis of the phospholipid phosphatidylcholine (PC). PC is a major lipid in eukaryotic cellular membranes, but it is considered to be comparatively rare in bacterial taxa. Using liquid chromatography-mass spectrometry in conjunction with stable isotope tracing, we determined that mitis group streptococci synthesize PC via a rare host-metabolite-scavenging pathway, the glycerophosphocholine (GPC) pathway, which is largely uncharacterized in bacteria. Our work demonstrates that mitis group streptococci, including S. pneumoniae , remodel their membranes in response to the major human metabolites GPC and lysophosphatidylcholine. IMPORTANCE We lack fundamental information about the composition of the cellular membrane even for the best-studied pathogens of critical significance for human health. The mitis group streptococci are closely linked to humans in health and disease, but their membrane biology is poorly understood. Here, we demonstrate that these streptococci scavenge major human metabolites and use them to synthesize the membrane phospholipid PC. Our work is significant because it identifies a mechanism by which the major human pathogen S. pneumoniae and the primary human oral colonizers S. mitis and S. oralis remodel their membranes in response to host metabolites., (Copyright © 2019 Joyce et al.)

Synthesis and integrity of the cytoplasmic membrane are fundamental to cellular life. Experimental evolution studies have hinted at unique physiology in the Gram-positive bacteria Streptococcus mitis and S. oralis These organisms commonly cause bacteremia and infectious endocarditis (IE) but are rarely investigated in mechanistic studies of physiology and evolution. Unlike in other Gram-positive pathogens, high-level (MIC ≥ 256 μg/ml) daptomycin resistance rapidly emerges in S. mitis and S. oralis after a single drug exposure. In this study, we found that inactivating mutations in cdsA are associated with high-level daptomycin resistance in S. mitis and S. oralis IE isolates. This is surprising given that cdsA is an essential gene for life in commonly studied model organisms. CdsA is the enzyme responsible for the synthesis of CDP-diacylglycerol, a key intermediate for the biosynthesis of all major phospholipids in prokaryotes and most anionic phospholipids in eukaryotes. Lipidomic analysis by liquid chromatography-mass spectrometry (LC-MS) showed that daptomycin-resistant strains have an accumulation of phosphatidic acid and completely lack phosphatidylglycerol and cardiolipin, two major anionic phospholipids in wild-type strains, confirming the loss of function of CdsA in the daptomycin-resistant strains. To our knowledge, these daptomycin-resistant streptococci represent the first model organisms whose viability is CdsA independent. The distinct membrane compositions resulting from the inactivation of cdsA not only provide novel insights into the mechanisms of daptomycin resistance but also offer unique opportunities to study the physiological functions of major anionic phospholipids in bacteria., (Copyright © 2017 Adams et al.)

We have previously reported that the Ser9Gly dopamine D3 receptor (DRD3) polymorphism was associated with increased rates of obsessive-compulsive personality disorder (OCPD) symptomology. We tested the replicability of this association within a further two independent groups of individuals with a history of depression, from a clinical sample (n = 149) and a family study (n = 213). The data from the replication samples and the original sample, within which the association was found, were compiled within a meta-analysis. Although the independent samples did not replicate the original finding, the meta-analysis elucidated significant evidence supporting the association. An individual with Gly/Gly genotype is 2.4 (P = 0.017) times more likely to be diagnosed with OCPD. Male gender was also found to be a significant predictor of OCPD diagnosis (OR = 2.82, P = 0.001). An exploration of an association of DRD3 with Axis I anxiety disorder diagnoses and Temperament and Character Inventory (TCI) traits, in particular persistence, revealed no support for an association. We conclude that DRD3 may contribute to the development of OCPD.