Indigenous Women and Their Nutrition During Pregnancy (the Mums and Bubs Deadly Diets Project): Protocol for a Co-designed mHealth Resource Development Study.

BACKGROUND: Nutrition in pregnancy is pivotal to optimizing infant growth and maternal well-being. The factors affecting Indigenous people's food and nutrition intake are complex with a history of colonization impacting the disproportionate effect of social determinants to this day. Literature regarding the dietary intake or dietary priorities of Indigenous women in Australia is scarce, with supportive, culturally appropriate resources developed for and with this group rare. Research suggests mobile health (mHealth) tools are effective in supporting health knowledge of Indigenous people and positive health behavior changes when designed and developed with the expertise of Indigenous communities. OBJECTIVE: This study seeks to build the body of knowledge related to nutrition needs and priorities for Indigenous women in Australia during pregnancy. Further, this project team and its participants will co-design an mHealth digital tool to support these nutrition needs. METHODS: The Mums and Bubs Deadly Diets study recruits Indigenous women and health care professionals who support Indigenous women during pregnancy into 2 phases. Phase 1 (predesign) uses a mixed methods convergent design using a biographical questionnaire and social or focus groups to inform phase 2 (generative). Phase 2 will use a participatory action research process during co-design workshops to iteratively develop the digital tool; the exact actions within a workshop will evolve according to the participant group decisions. RESULTS: To date, this project has undertaken phase 1 focus groups at all Queensland sites, with New South Wales and Western Australia to begin in early to mid-2023. We have recruited 12 participants from Galangoor Duwalami, 18 participants from Carbal in Toowoomba, and 18 participants from Carbal in Warwick. We are expecting similar numbers of recruits in Western Australia and New South Wales. Participants have been both community members and health care professionals. CONCLUSIONS: This study is an iterative and adaptive research program that endeavors to develop real-world, impactful resources to support the nutrition needs and priorities of pregnant Indigenous women in Australia. This comprehensive project requires a combination of methods and methodologies to ensure Indigenous voices are heard at each stage and in all aspects of research output. The development of an mHealth resource for this cohort will provide a necessary bridge where there is often a gap in access to nutrition resources for women in pregnancy in Indigenous communities. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/45983.

Autolysin-mediated peptidoglycan hydrolysis is required for the surface display of Staphylococcus aureus cell wall-anchored proteins.

Peptidoglycan hydrolases, or autolysins, play a critical role in cell wall remodeling and degradation, facilitating bacterial growth, cell division, and cell separation. In Staphylococcus aureus, the so-called "major" autolysin, Atl, has long been associated with host adhesion; however, the molecular basis underlying this phenomenon remains understudied. To investigate, we used the type V glycopeptide antibiotic complestatin, which binds to peptidoglycan and blocks the activity of autolysins, as a chemical probe of autolysin function. We also generated a chromosomally encoded, catalytically inactive variant of the Atl enzyme. Autolysin-mediated peptidoglycan hydrolysis, in particular Atl-mediated daughter cell separation, was shown to be critical for maintaining optimal surface levels of S. aureus cell wall-anchored proteins, including the fibronectin-binding proteins (FnBPs) and protein A (Spa). As such, disrupting autolysin function reduced the affinity of S. aureus for host cell ligands, and negatively impacted early stages of bacterial colonization in a systemic model of S. aureus infection. Phenotypic studies revealed that Spa was sequestered at the septum of complestatin-treated cells, highlighting that autolysins are required to liberate Spa during cell division. In summary, we reveal the hydrolytic activities of autolysins are associated with the surface display of S. aureus cell wall-anchored proteins. We demonstrate that by blocking autolysin function, type V glycopeptide antibiotics are promising antivirulence agents for the development of strategies to control S. aureus infections.

A genetic platform to investigate the functions of bacterial drug efflux pumps.

Efflux pumps are a serious challenge for the development of antibacterial agents. Overcoming efflux requires an in-depth understanding of efflux pump functions, specificities and the development of inhibitors. However, the complexities of efflux networks have limited such studies. To address these challenges, we generated Efflux KnockOut-35 (EKO-35), a highly susceptible Escherichia coli strain lacking 35 efflux pumps. We demonstrate the use of this strain by constructing an efflux platform comprising EKO-35 strains individually producing efflux pumps forming tripartite complexes with TolC. This platform was profiled against a curated diverse compound collection, which enabled us to define physicochemical properties that contribute to transport. We also show the E. coli drug efflux network is conditionally essential for growth, and that the platform can be used to investigate efflux pump inhibitor specificities and efflux pump interplay. We believe EKO-35 and the efflux platform will have widespread application for the study of drug efflux.

Preclinical Evaluation of Recombinant Microbial Glycoside Hydrolases as Antibiofilm Agents in Acute Pulmonary Pseudomonas aeruginosa Infection.

The bacterium Pseudomonas aeruginosa can colonize the airways of patients with chronic lung disease. Within the lung, P. aeruginosa forms biofilms that can enhance resistance to antibiotics and immune defenses. P. aeruginosa biofilm formation is dependent on the secretion of matrix exopolysaccharides, including Pel and Psl. In this study, recombinant glycoside hydrolases (GHs) that degrade Pel and Psl were evaluated alone and in combination with antibiotics in a mouse model of P. aeruginosa infection. Intratracheal GH administration was well tolerated by mice. Pharmacokinetic analysis revealed that, although GHs have short half-lives, administration of two GHs in combination resulted in increased GH persistence. Combining GH prophylaxis and treatment with the antibiotic ciprofloxacin resulted in greater reduction in pulmonary bacterial burden than that with either agent alone. This study lays the foundation for further exploration of GH therapy in bacterial infections.

PROcalcitonin and NEWS2 evaluation for Timely identification of sepsis and Optimal use of antibiotics in the emergency department (PRONTO): protocol for a multicentre, open-label, randomised controlled trial.

INTRODUCTION: Sepsis is a common, potentially life-threatening complication of infection. The optimal treatment for sepsis includes prompt antibiotics and intravenous fluids, facilitated by its early and accurate recognition. Currently, clinicians identify and assess severity of suspected sepsis using validated clinical scoring systems. In England, the National Early Warning Score 2 (NEWS2) has been mandated across all National Health Service (NHS) trusts and ambulance organisations. Like many clinical scoring systems, NEWS2 should not be used without clinical judgement to determine either the level of acuity or a diagnosis. Despite this, there is a tendency to overemphasise the score in isolation in patients with suspected infection, leading to the overprescription of antibiotics and potentially treatment-related complications and rising antimicrobial resistance. The biomarker procalcitonin (PCT) has been shown to be useful in specific circumstances to support appropriate antibiotics prescribing by identifying bacterial infection. PCT is not routinely used in the care of undifferentiated patients presenting to emergency departments (EDs), and the evidence base of its optimal usage is poor. The PROcalcitonin and NEWS2 evaluation for Timely identification of sepsis and Optimal (PRONTO) study is a randomised controlled trial (RCT) in adults with suspected sepsis presenting to the ED to compare standard clinical management based on NEWS2 scoring plus PCT-guided risk assessment with standard clinical management based on NEWS2 scoring alone and compare if this approach reduces prescriptions of antibiotics without increasing mortality. METHODS AND ANALYSIS: PRONTO is a parallel two-arm open-label individually RCT set in up to 20 NHS EDs in the UK with a target sample size of 7676 participants. Participants will be randomised in a ratio of 1:1 to standard clinical management based on NEWS2 scoring or standard clinical management based on NEWS2 scoring plus PCT-guided risk assessment. We will compare whether the addition of PCT measurement to NEWS2 scoring can lead to a reduction in intravenous antibiotic initiation in ED patients managed as suspected sepsis, with at least no increase in 28-day mortality compared with NEWS2 scoring alone (in conjunction with local standard care pathways). PRONTO has two coprimary endpoints: initiation of intravenous antibiotics at 3 hours (superiority comparison) and 28-day mortality (non-inferiority comparison). The study has an internal pilot phase and group-sequential stopping rules for effectiveness and futility/safety, as well as a qualitative substudy and a health economic evaluation. ETHICS AND DISSEMINATION: The trial protocol was approved by the Health Research Authority (HRA) and NHS Research Ethics Committee (Wales REC 2, reference 20/WA/0058). In England and Wales, the law allows the use of deferred consent in approved research situations (including ED studies) where the time dependent nature of intervention would not allow true informed consent to be obtained. PRONTO has approval for a deferred consent process to be used. Findings will be disseminated through peer-reviewed journals and presented at scientific conferences. TRIAL REGISTRATION NUMBER: ISRCTN54006056.

North American Study for the Treatment of Recurrent Epistaxis with Doxycycline: The NOSTRIL trial.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is a vascular bleeding disorder characterized by mucocutaneous telangiectasias and visceral arteriovenous malformations. A frequently debilitating symptom is spontaneous recurrent epistaxis. OBJECTIVE: To evaluate whether doxycycline therapy improves epistaxis in HHT by using a prospective, randomized, placebo-controlled crossover study design. PATIENTS/METHODS: Twenty-two eligible patients between December 2017 and July 2020 at a single center were randomized to one of two study arms: doxycycline treatment followed by placebo, or vice versa. Primary outcomes measured differences in epistaxis severity between treatments. Changes in quality of life, laboratory markers of bleeding, and number of monthly blood transfusions or iron infusions were assessed as secondary endpoints. Additional post hoc endpoints included frequency and duration of dripping epistaxis and gushing epistaxis. A post hoc longitudinal analysis assessed effects of doxycycline over time. RESULTS/CONCLUSIONS: Doxycycline was safe and well tolerated. However, there was no reduction in the three primary outcome measures, nosebleed frequency (p = .16), nosebleed duration (p = .05), and Epistaxis Severity Score (p = .19). Quality of life, hemoglobin level, and number of blood transfusions and iron infusions did not differ between groups. Post hoc analysis demonstrated reduction in instances of gushing (p = .02) with doxycycline, although this finding is of unclear clinical significance. Post hoc longitudinal analysis showed reduction in frequency (mean estimate of coefficient = -0.19, standard error = 0.07, p = .01) and duration (mean estimate of coefficient = -2.33, standard error = 1.08, p = .03) of epistaxis over time. Post hoc findings suggest possible benefit of doxycycline but should be interpreted with caution given the overall negative study. Further investigation is needed with a larger sample size and a longer treatment duration.

Genicular Artery Embolization for the Treatment of Symptomatic Knee Osteoarthritis.

Genicular artery embolization (GAE) is a novel therapy to treat patients with symptomatic knee osteoarthritis (OA) by reducing synovial arterial hypervascularity. This study evaluates the safety and efficacy of GAE for the treatment of symptomatic knee OA. METHODS: A prospective, single-center, open-label U.S. Food and Drug Administration-approved investigational device exemption study was conducted. Patients enrolled in the study were 40 to 80 years old, with moderate or severe knee OA (Kellgren-Lawrence grade 2, 3, or 4), who previously had failure of conservative therapy. Baseline pain (visual analog scale [VAS]) and symptom scores (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]) were assessed. After femoral arterial access was achieved, GAE of 1, 2, or 3 genicular arteries supplying the location of the subject's pain, as determined by digital subtraction angiography and cone-beam computed tomography, was performed using 100-µm particles. Adverse events and symptoms scores were assessed at 1 week, 1 month, 3 months, 6 months, and 1 year after GAE. RESULTS: Over a 10-month period, 40 subjects were enrolled. The median age was 69 years (range, 49 to 80 years). The median body mass index was 29 kg/m2 (range, 19 to 44 kg/m2). Knee OA severity was grade 2 in 18% of the patients, grade 3 in 43%, and grade 4 in 40%. Technical success was achieved in 100% of the subjects. Transient skin discoloration and transient mild knee pain after the procedure were common and expected. Treatment-related adverse events included a groin hematoma requiring overnight observation in 1 subject, self-resolving focal skin ulceration in 7 subjects, and an asymptomatic small bone infarct on magnetic resonance imaging at 3 months in 2 subjects. The WOMAC total and VAS pain scores decreased by 61% and 67% at 12 months from a median baseline of 52 (of 96) and 8 (of 10), respectively. Twenty-seven patients (68%) had a reduction of ≥50% in both WOMAC total and VAS pain scores. CONCLUSIONS: This prospective trial demonstrates that GAE is effective and durable in reducing pain symptoms from moderate or severe knee OA that is refractory to other conservative therapy, with an acceptable safety profile. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Perioperative outcomes for patients on chronic buprenorphine undergoing spine surgery: A case series.

OBJECTIVE: Pain management following spine surgery can be challenging as patients routinely suffer from chronic pain and opioid tolerance. The increasing popularity of buprenorphine use for pain management in this population may further complicate perioperative pain management due to the limited efficacy of other opioids in the presence of buprenorphine. This study describes perioperative management and outcomes in patients on chronic buprenorphine who underwent elective inpatient spine surgery. DESIGN: The authors performed a retrospective chart review of all patients >18 years of age taking chronic buprenorphine for any indication who had elective inpatient spine surgery at a single institution. Perioperative pain management data were analyzed for all patients who underwent spine surgery and were maintained on buprenorphine during their hospital stay. SETTING: The study was performed at a single tertiary academic medical center. MAIN OUTCOME MEASURES: The primary outcome measures were post-operative pain scores and analgesic medication requirements. RESULTS: Twelve patients on buprenorphine underwent inpatient spine surgery. Acceptable pain control was achieved in all cases. Management included preoperative dose limitation of buprenorphine when indicated and the extensive use of multimodal analgesia. CONCLUSION: The question whether patients presenting for painful, elective surgery should continue using buprenorphine perioperatively is an area of controversy, and the present manuscript provides more evidence for the concept of therapy continuation with buprenorphine.

Preclinical Evaluation of Recombinant Microbial Glycoside Hydrolases in the Prevention of Experimental Invasive Aspergillosis.

Aspergillus fumigatus is a ubiquitous mold that can cause invasive pulmonary infections in immunocompromised patients. Within the lung, A. fumigatus forms biofilms that can enhance resistance to antifungals and immune defenses. Aspergillus biofilm formation requires the production of a cationic matrix exopolysaccharide, galactosaminogalactan (GAG). In this study, recombinant glycoside hydrolases (GH)s that degrade GAG were evaluated as antifungal agents in a mouse model of invasive aspergillosis. Intratracheal GH administration was well tolerated by mice. Pharmacokinetic analysis revealed that although GHs have short half-lives, GH prophylaxis resulted in reduced fungal burden in leukopenic mice and improved survival in neutropenic mice, possibly through augmenting pulmonary neutrophil recruitment. Combining GH prophylaxis with posaconazole treatment resulted in a greater reduction in fungal burden than either agent alone. This study lays the foundation for further exploration of GH therapy in invasive fungal infections. IMPORTANCE The biofilm-forming mold Aspergillus fumigatus is a common causative agent of invasive fungal airway disease in patients with a compromised immune system or chronic airway disease. Treatment of A. fumigatus infection is limited by the few available antifungals to which fungal resistance is becoming increasingly common. The high mortality rate of A. fumigatus-related infection reflects a need for the development of novel therapeutic strategies. The fungal biofilm matrix is in part composed of the adhesive exopolysaccharide galactosaminogalactan, against which antifungals are less effective. Previously, we demonstrated antibiofilm activity with recombinant forms of the glycoside hydrolase enzymes that are involved in galactosaminogalactan biosynthesis. In this study, prophylaxis with glycoside hydrolases alone or in combination with the antifungal posaconazole in a mouse model of experimental aspergillosis improved outcomes. This study offers insight into the therapeutic potential of combining biofilm disruptive agents to leverage the activity of currently available antifungals.

The C.A.R.E. model of employee bereavement support.

Virtually every employee will experience bereavement and grief at some point in their careers, but organizations are often ill-prepared to support grieving employees. Little empirical work has been conducted on the experience of grief in the workplace, and this study answers calls for research on the subject. We interviewed bereaved employees (N = 14) who continued to work full-time. Data was analyzed using thematic analysis conducted by three independent coders. The results suggested four key themes that characterized effective bereavement support in the workplace and that together comprise the C.A.R.E. model of bereavement support-vis: (1) communication, (2) accommodation, (3) recognition of the loss, and (4) emotional support. The results provide insight into critical ways that employers, leaders, and coworkers can support grieving employees. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Randomised controlled trial and economic evaluation of a targeted cancer awareness intervention for adults living in deprived areas of the UK.

BACKGROUND: Cancer outcomes are poor in socioeconomically deprived communities, with low symptom awareness contributing to prolonged help-seeking and advanced disease. Targeted cancer awareness interventions require evaluation. METHODS: This is a randomised controlled trial involving adults aged 40+ years recruited in community and healthcare settings in deprived areas of South Yorkshire and South-East Wales. INTERVENTION: personalised behavioural advice facilitated by a trained lay advisor. CONTROL: usual care. Follow-up at two weeks and six months post-randomisation. PRIMARY OUTCOME: total cancer symptom recognition score two weeks post-randomisation. RESULTS: Two hundred and thirty-four participants were randomised. The difference in total symptom recognition at two weeks [adjusted mean difference (AMD) 0.6, 95% CI: -0.03, 1.17, p = 0.06] was not statistically significant. Intervention participants reported increased symptom recognition (AMD 0.8, 95% CI: 0.18, 1.37, p = 0.01) and earlier intended presentation (AMD -2.0, 95% CI: -3.02, -0.91, p < 0.001) at six months. "Lesser known" symptom recognition was higher in the intervention arm (2 weeks AMD 0.5, 95% CI: 0.03, 0.97 and six months AMD 0.7, 95% CI: 0.16, 1.17). Implementation cost per participant was £91.34, with no significant between-group differences in healthcare resource use post-intervention. CONCLUSIONS: Improved symptom recognition and earlier anticipated presentation occurred at longer-term follow-up. The ABACus Health Check is a viable low-cost intervention to increase cancer awareness in socioeconomically deprived communities. CLINICAL TRIAL REGISTRATION: ISRCTN16872545.

Protective Liquid Crystal Nanoparticles for Targeted Delivery of PslG: A Biofilm Dispersing Enzyme.

The glycoside hydrolase, PslG, attacks and degrades the dominant Psl polysaccharide in the exopolymeric substance (EPS) matrix of Pseudomonas aeruginosa biofilms and is a promising therapy to potentiate the effect of antibiotics. However, the need for coadministration with an antibiotic and the potential susceptibility of PslG to proteolysis highlights the need for an effective delivery system. Here, we compared liposomes versus lipid liquid crystal nanoparticles (LCNPs) loaded with PslG and tobramycin as potential formulation approaches to (1) protect PslG from proteolysis, (2) trigger the enzyme's release in the presence of bacteria, and (3) improve the total antimicrobial effect in vitro and in vivo in a Caenorhabditis elegans infection model. LCNPs were an effective formulation strategy for PslG and tobramycin that better protected the enzyme against proteolysis, triggered and sustained the release of PslG, improved the antimicrobial effect by 10-100-fold, and increased the survival of C. elegans infected with P. aeruginosa. Digestible LCNPs had the advantage of triggering the enzyme's release in the presence of bacteria. However, compared to nondigestible LCNPs, negligible differences arose between the LCNPs' ability to protect PslG from proteolysis and potentiate the antimicrobial activity in combination with tobramycin. In C. elegans, the improved antimicrobial efficacy was comparable to tobramycin-LCNPs, although the PslG + tobramycin-LCNPs achieved a greater than 10-fold reduction in bacteria compared to the unformulated combination. Herewith, LCNPs are showcased as a promising protective delivery system for novel biofilm dispersing enzymes combined with antibiotics, enabling infection-directed therapy and improved performance.

Preventing Pseudomonas aeruginosa Biofilms on Indwelling Catheters by Surface-Bound Enzymes.

Implanted medical devices such as central venous catheters are highly susceptible to microbial colonization and biofilm formation and are a major risk factor for nosocomial infections. The opportunistic pathogen Pseudomonas aeruginosa uses exopolysaccharides, such as Psl, for both initial surface attachment and biofilm formation. We have previously shown that chemically immobilizing the Psl-specific glycoside hydrolase, PslGh, to a material surface can inhibit P. aeruginosa biofilm formation. Herein, we show that PslGh can be uniformly immobilized on the lumen surface of medical-grade, commercial polyethylene, polyurethane, and polydimethylsiloxane (silicone) catheter tubing. We confirmed that the surface-bound PslGh was uniformly distributed along the catheter length and remained active even after storage for 30 days at 4 °C. P. aeruginosa colonization and biofilm formation under dynamic flow culture conditions in vitro showed a 3-log reduction in the number of bacteria during the first 11 days, and a 2-log reduction by day 14 for PslGh-modified PE-100 catheters, compared to untreated catheter controls. In an in vivo rat infection model, PslGh-modified PE-100 catheters showed a ∼1.5-log reduction in the colonization of the clinical P. aeruginosa ATCC 27853 strain after 24 h. These results demonstrate the robust ability of surface-bound glycoside hydrolase enzymes to inhibit biofilm formation and their potential to reduce rates of device-associated infections.

Recruitment and retention of participants from socioeconomically deprived communities: lessons from the Awareness and Beliefs About Cancer (ABACus3) Randomised Controlled Trial.

BACKGROUND: Recruitment of research participants poses challenges in socioeconomically deprived areas. The Awareness and Beliefs About Cancer (ABACus) phase 3 Randomised Control Trial recruited adult participants from socioeconomically deprived areas using a combined healthcare/community engagement model. We report the strategies used to successfully recruit and retain our trial participant sample. METHODS: Community and healthcare settings in areas of high socioeconomic deprivation were identified by lay advisors who recruited participants opportunistically or by appointment. Follow-up was done by telephone or post at 2-weeks and 6-months after recruitment, and all participants were offered financial incentives. Qualitative interviews were conducted with lay advisors regarding their experience and reflections. RESULTS: The lay advisors identified and contacted 107 potential recruitment venues across South and West Yorkshire and South East Wales of which 41.1% (n = 42) were opened for recruitment. A total of 234 participants were recruited, with 91% (n = 212) retention at 2-weeks and 85% (n = 199) at 6-months. Community settings yielded 75% (n = 176) of participants. Participants had a mean age of 61.3 years and 63.3% (n = 148) were female, with 66% (n = 154) resident in the most deprived geographical areas. Lay advisors described recruitment as intensive, although engaging participants was easier in community settings. CONCLUSIONS: The ABACus3 trial achieved recruitment and high retention with a population that is often "hard to reach" or entirely missed in health research. Strategies were specifically tailored to engage the venues and adult residents of highly deprived areas. Future studies recruiting adults living in the most deprived areas might benefit from community recruitment and from collaborating with local gatekeepers who are key to engagement. This study adheres to CONSORT guidelines. TRIAL REGISTRATION: Retrospectively registered with ISRCTN ( http://www.isrctn.com/ISRCTN16872545 ) on 12.01.2018.

Factors influencing contraceptive use or non-use among Aboriginal and Torres Strait Islander people: a systematic review and narrative synthesis.

BACKGROUND: The Australian population has an unmet need for contraception. However, evidence suggests contraceptive patterns of Aboriginal and Torres Strait Islander populations are unique. To tailor contraceptive services and meet the contraceptive needs of Aboriginal and Torres Strait Islander people, it is important to understand the contributing factors to contraceptive use and non-use. METHODS: This study aimed to systematically review and narratively synthesise the evidence exploring the factors influencing contraceptive use among Aboriginal and Torres Strait Islander people. A systematic literature search was initially run in September 2016 and was updated again in April and August of 2018. A qualitative narrative synthesis was conducted from 2018 to 2019. Factors influencing contraceptive use or non-use were explored using a Social Ecological Model. RESULTS: The review identified 17 studies meeting the inclusion criteria published between 1972 and 2018. Most of the included studies were qualitative (n = 11), with the remaining studies being mixed methods (n = 3) or quantitative (n = 3). The majority focused on either a localised geographic area or specific Aboriginal or Torres Strait Islander community (n = 11). One study specifically focused on factors influencing contraceptive use, albeit among postpartum women. The remaining studies discussed factors influencing contraceptive use within the context of risky behaviour, sexual transmitted infections, or contraceptive practices more generally. Factors unique to individual communities included community attitudes (e.g. importance of not being too young to have a baby), specific cultural norms (e.g. subincising the penis as part of transition to manhood), and access to culturally appropriate health services. Other factors, including contraceptive characteristics (e.g. discomfort of condoms) and reproductive coercion (e.g. partner wants a baby), were similar to those found in the broader population of Australia and internationally. Most studies were lacking in quality, warranting more methodologically sound studies in the future to further assess the factors contributing to contraceptive use or non-use among Aboriginal and Torres Strait Islander people. CONCLUSIONS: Identifying community specific facilitators, as well as understanding the more broadly applicable factors contributing to contraceptive use or non-use, is essential if wanting to offer appropriate contraceptive services within an Aboriginal or Torres Strait Islander community.

A Key Glycine in Bacterial Steroid-Degrading Acyl-CoA Dehydrogenases Allows Flavin-Ring Repositioning and Modulates Substrate Side Chain Specificity.

A wide variety of steroid metabolites synthesized by eukaryotes are all ultimately catabolized by bacteria; while generally saprophytic, pathogenic Mycobacteria have repurposed these pathways to utilize host intracellular cholesterol pools. Steroid degradation is complex, but a recurring theme is that cycles of ß-oxidation are used to iteratively remove acetyl- or propanoyl-CoA groups. These ß-oxidation cycles are initiated by the FAD-dependent oxidation of acyl groups, catalyzed by acyl-CoA dehydrogenases (ACADs). We show here that the tcur3481 and tcur3483 genes of Thermomonospora curvata encode subunits of a single ACAD that degrades steroid side chains with a preference for three-carbon over five-carbon substituents. The structure confirms that this enzyme is heterotetrameric, with active sites only in the Tcur3483 subunits. In comparison with the steroid ACAD FadE26-FadE27 from Mycobacterium tuberculosis, the active site is narrower and closed at the steroid-binding end, suggesting that Tcur3481-Tcur3483 is in a catalytically productive state, while FadE26-FadE27 is opened up to allow substrate entry. The flavin rings in Tcur3481-Tcur3483 sit in an unusual pocket created by Gly363, a residue conserved as Ala in steroid ACADs narrowly specific for five-carbon side chains, including FadE34. A Gly363Ala variant of Tcur3481-Tcur3483 prefers five-carbon side chains, while an inverse Ala691Gly FadE34 variant enables three-carbon side chain steroid oxidation. We determined the structure of the Tcur3483 Gly363Ala variant, showing that the flavin rings shift into the more conventional position. Modeling suggests that the shifted flavin position made possible by Gly363 is required to allow the bulky, inflexible three-carbon steroid to bind productively in the active site.

The steroid side-chain-cleaving aldolase Ltp2-ChsH2DUF35 is a thiolase superfamily member with a radically repurposed active site.

An aldolase from the bile acid-degrading actinobacterium Thermomonospora curvata catalyzes the C-C bond cleavage of an isopropyl-CoA side chain from the D-ring of the steroid metabolite 17-hydroxy-3-oxo-4-pregnene-20-carboxyl-CoA (17-HOPC-CoA). Like its homolog from Mycobacterium tuberculosis, the T. curvata aldolase is a protein complex of Ltp2 with a DUF35 domain derived from the C-terminal domain of a hydratase (ChsH2DUF35) that catalyzes the preceding step in the pathway. We determined the structure of the Ltp2-ChsH2DUF35 complex at 1.7 Å resolution using zinc-single anomalous diffraction. The enzyme adopts an αßßα organization, with the two Ltp2 protomers forming a central dimer, and the two ChsH2DUF35 protomers being at the periphery. Docking experiments suggested that Ltp2 forms a tight complex with the hydratase but that each enzyme retains an independent CoA-binding site. Ltp2 adopted a fold similar to those in thiolases; however, instead of forming a deep tunnel, the Ltp2 active site formed an elongated cleft large enough to accommodate 17-HOPC-CoA. The active site lacked the two cysteines that served as the nucleophile and general base in thiolases and replaced a pair of oxyanion-hole histidine residues with Tyr-246 and Tyr-344. Phenylalanine replacement of either of these residues decreased aldolase catalytic activity at least 400-fold. On the basis of a 17-HOPC-CoA -docked model, we propose a catalytic mechanism where Tyr-294 acts as the general base abstracting a proton from the D-ring hydroxyl of 17-HOPC-CoA and Tyr-344 as the general acid that protonates the propionyl-CoA anion following C-C bond cleavage.

Validation Study of the Transfusion Risk and Clinical Knowledge (TRACK) Tool in Cardiac Surgery Patients: A Retrospective Analysis.

OBJECTIVE: The Transfusion Risk and Clinical Knowledge (TRACK) scoring system has been developed for predicting perioperative blood transfusions. However, the TRACK score needs to be validated externally in the US population. The primary objective of this study is to validate TRACK at the authors' institution. DESIGN: This study was a single-center retrospective analysis. SETTING: Operating room and intensive care units of academic medical center. PARTICIPANTS: Adult cardiac surgery patients. INTERVENTIONS: The authors retrospectively queried all cardiac surgeries at the authors' institution between 2010 and 2015 from the Society of Thoracic Surgeons database. The TRACK scores were determined for all patients. The authors used receiver operating characteristic (ROC) curves to assess the discriminatory power of TRACK in predicting any perioperative, intraoperative, and postoperative transfusions. The maximum Youden's index was used to determine optimal cutoff scores for predicting perioperative transfusions. MEASUREMENTS AND MAIN RESULTS: The authors analyzed 2,776 cardiac surgery patients with 51.8% transfused perioperatively. The average TRACK score (mean ± standard deviation) in transfused versus non-transfused patients was 12.4 ± 7.2 versus 6.1 ± 5.4, respectively (p < 0.001). The area under the ROC curve was 0.768 (95% confidence interval 0.800-0.835, p < 0.001) for any perioperative transfusion. Optimal sensitivity (67%) and specificity (73%) for predicting any perioperative transfusions was achieved with a TRACK score cutoff of greater than or equal to 22 of 32. CONCLUSION: This study demonstrates the validity of the TRACK score in predicting blood perioperative transfusions in cardiac surgery patients at the authors' institution. This study supports the external validity of TRACK and adds to its clinical utility by establishing cutoff scores for identifying patients at high risk of transfusion.

Development and Validation of the LEADS Scale.

LEADS in a Caring Environment has been adopted as the primary leadership framework by the Canadian Health Leadership Network. This study developed and validated a 20-item behaviourally anchored rating scale to assess the twenty LEADS capabilities. Canadian healthcare employees and support staff (N = 156) were asked to rate their managers using the scale and also completed measures of transformational leadership, job-related affective well-being, and intent to stay for validation purposes. Exploratory factor analysis suggested that the scale was best represented by a single factor structure. A shorter five-item scale was also developed and tested based on factor loadings. Internal consistency of both tools was high (α ≥ 0.96) and results supported their criterion validity for predicting turnover intentions and job-related affective well-being and convergent validity with a measure of transformational leadership.

The effect of ice slurry ingestion on body temperature and cycling performance in competitive athletes.

The effects of pre cooling on endurance performance are widely known. In contrast, the approach of cooling during endurance exercise in combination with pre-exercise cooling has been poorly understood. The purpose of the present study was to determine whether the effects of precooling and cooling during exercise enhance exercise performance compared to the ingestion of a thermo-neutral beverage (20 °C) or precooling alone in cycling performance. This was an experimental study using a randomised crossover design in which 7 cyclists underwent three trials comprising of 45 min steady state cycling (SS) at 70% VO2 max and a subsequent 10 km time trial (TT) in hot conditions (32 °C, 50% relative humidity). Rectal temperature (Tre), heat storage (HS), heart rate (HR), blood lactate concentration (BLA) and thermal sensation (TS) were measured. The intervention consisted of: (1) ingestion of thermo-neutral beverage before and during SS cycling (TN), (2) ingestion of ice slurry beverage and application of iced towels (precooling) prior to exercise, and then ingestion of thermo-neutral beverage during SS (PRE) and (3) precooling strategy as above plus ice slurry ingestion during SS cycling (PRE + MID). The intake of thermo-neutral or ice slurry beverage (14 g/kg) occurred over 30 min before and every 15 min during SS cycling. There was no significant difference in TT performance between all the conditions (P =0.72). However, PRE and PRE + MID caused a significant decrease in Tre (P < 0.05) from TN during exercise. Accordingly, both precooling and a combination of precooling and mid-cooling during exercise in hot conditions may be a practical and effective way of reducing core temperature. Future studies should investigate longer distance events and timing of ice slurry ingestion.