On the Validation of Protein Force Fields Based on Structural Criteria

Molecular dynamics simulations depend critically on the quality of the force field used to describe the interatomic interactions and the extent to which it has been validated for use in a specific application. Using a curated test set of 52 high-resolution structures, 39 derived from X-ray diffraction and 13 solved using NMR, we consider the extent to which different parameter sets of the GROMOS protein force field can be distinguished based on comparing a range of structural criteria, including the number of backbone hydrogen bonds, the number of native hydrogen bonds, polar and nonpolar solvent-accessible surface area, radius of gyration, the prevalence of secondary structure elements, J-coupling constants, nuclear Overhauser effect (NOE) intensities, positional root-mean-square deviations (RMSD), and the distribution of backbone ϕ and ψ dihedral angles. It is shown that while statistically significant differences between the average values of individual metrics could be detected, these were in general small. Furthermore, improvements in agreement in one metric were often offset by loss of agreement in another. The work establishes a framework and test set against which protein force fields can be validated. It also highlights the danger of inferring the relative quality of a given force field based on a small range of structural properties or small number of proteins.

Nationally Automated Colonoscopy Performance Feedback Increases Polyp Detection: The NED APRIQOT Randomized Controlled Trial

BACKGROUND & AIMS

Postcolonoscopy colorectal cancer incidence and mortality rates are higher for endoscopists with low polyp detection rates. Using the UK's National Endoscopy Database (NED), which automatically captures real-time data, we assessed if providing feedback of case-mix-adjusted mean number of polyps (aMNP), as a key performance indicator, improved endoscopists' performance. Feedback was delivered via a theory-informed, evidence-based audit and feedback intervention.

METHODS

This multicenter, prospective, NED Automated Performance Reports to Improve Quality Outcomes Trial randomized National Health Service endoscopy centers to intervention or control. Intervention-arm endoscopists were e-mailed tailored monthly reports automatically generated within NED, informed by qualitative interviews and behavior change theory. The primary outcome was endoscopists' aMNP during the 9-month intervention.

RESULTS

From November 2020 to July 2021, 541 endoscopists across 36 centers (19 intervention; 17 control) performed 54,770 procedures during the intervention, and 15,960 procedures during the 3-month postintervention period. Comparing the intervention arm with the control arm, endoscopists during the intervention period: aMNP was nonsignificantly higher (7%; 95% CI, -1% to 14%; P = .08). The unadjusted MNP (10%; 95% CI, 1%-20%) and polyp detection rate (10%; 95% CI, 4%-16%) were significantly higher. Differences were not maintained in the postintervention period. In the intervention arm, endoscopists accessing NED Automated Performance Reports to Improve Quality Outcomes Trial webpages had a higher aMNP than those who did not (aMNP, 118 vs 102; P = .03).

CONCLUSIONS

Although our automated feedback intervention did not increase aMNP significantly in the intervention period, MNP and polyp detection rate did improve significantly. Engaged endoscopists benefited most and improvements were not maintained postintervention; future work should address engagement in feedback and consider the effectiveness of continuous feedback.

CLINICAL TRIALS REGISTRY

 www.isrctn.org ISRCTN11126923 .

Viable Vitreous Grafts of Whole Porcine Menisci for Transplant in the Knee and Temporomandibular Joints

The shortage of suitable donor meniscus grafts from the knee and temporomandibular joint (TMJ) impedes treatments for millions of patients. Vitrification offers a promising solution by transitioning these tissues into a vitreous state at cryogenic temperatures, protecting them from ice crystal damage using high concentrations of cryoprotectant agents (CPAs). However, vitrification's success is hindered for larger tissues (>3 mL) due to challenges in CPA penetration. Dense avascular meniscus tissues require extended CPA exposure for adequate penetration; however, prolonged exposure becomes cytotoxic. Balancing penetration and reducing cell toxicity is required. To overcome this hurdle, a simulation-based optimization approach is developed by combining computational modeling with microcomputed tomography (µCT) imaging to predict 3D CPA distributions within tissues over time accurately. This approach minimizes CPA exposure time, resulting in 85% viability in 4-mL meniscal specimens, 70% in 10-mL whole knee menisci, and 85% in 15-mL whole TMJ menisci (i.e., TMJ disc) post-vitrification, outperforming slow-freezing methods (20%-40%), in a pig model. The extracellular matrix (ECM) structure and biomechanical strength of vitreous tissues remain largely intact. Vitreous meniscus grafts demonstrate clinical-level viability (≥70%), closely resembling the material properties of native tissues, with long-term availability for transplantation. The enhanced vitrification technology opens new possibilities for other avascular grafts.

Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Effects of the multi-channeled oral irrigation (MCOI) unit in preventing dental plaque formation and gingivitis: A randomized controlled trial

PURPOSE

To evaluate the efficacy of COMORAL a new multi-channeled oral irrigation (MCOI) unit with pulsating water jet, in plaque score reduction and gingivitis.

METHODS

This was a single-blinded clinical randomized controlled trial (NCT05031260). Forty-two healthy subjects between 18 to 35 years old were initially recruited, and the control group (n = 20) and the intervention group (n = 17) were randomly assigned. Both groups were asked to brush their teeth one or two times a day without any supplementary oral hygiene products while the intervention group used COMORAL 3 times a day, 5 days a week. Clinical indices including gingival index (GI), plaque index (PI), bleeding on probing (BOP), pocket depth (PD), gingival recession (GR), and clinical attachment loss (CAL) were obtained at the baseline (D0), day 14 (D14), and day 28 (D28). Saliva was collected to examine the presence of periodontal pathogens. The repeated measures analysis of variance or generalized estimating equation was used to compare the interaction between groups and time points. The independent t-test or Mann-Whitney test were used for intergroup differences at each time point.

RESULTS

At V0, PI, GI, BOP, and PD scores showed no differences between the two groups. At V1 and V2, these scores showed significant difference between two groups (P < 0.05) such that the intervention group showed gradual decreases while the control group showed no change. There were no differences in GR, CAL, and periodontal pathogens between the two groups. COMORAL showed improvement in reducing gingival inflammation and dental plaque formation adjuvant to routine toothbrushing in healthy adults.

CLINICAL SIGNIFICANCE

The results of this study can be useful to clinicians when selecting oral hygiene devices that can help improve patients' routine oral hygiene practice and their overall oral health.

Early urodynamic findings after complete primary repair of exstrophy

INTRODUCTION

Detrusor contraction in bladder exstrophy (BE) patients following reconstruction is poorly understood as there are few published studies assessing urodynamic findings in this population. Understanding the ability of the detrusor to contract in BE patients early after closure may be able to inform the longer-term management and potential for the development of future continence in this population.

OBJECTIVE

We sought to evaluate early detrusor contraction using urodynamic studies (UDS) in children who had previously undergone complete primary repair of bladder exstrophy (CPRE). We hypothesized that a majority of children with BE would display the presence of normal detrusor contractile function after CPRE.

STUDY DESIGN

A retrospective review of our prospectively collected database was performed for all patients with a diagnosis of classic BE who underwent primary CPRE between 2013 and 2017. From this cohort we identified patients with at least one post-operative UDS at 3 years of age or older who had undergone an initial CPRE. Our primary outcome was the presence of a detrusor contraction demonstrated on UDS.

RESULTS

There were 50 children (31 male, 19 female) with CBE who underwent CPRE between 2013 and 2017.There were 26 (13 male, 13 female) who met inclusion criteria. Median age was 3.5 (IQR: 3.2-4.7) years at the time of UDS Sixteen of the 26 (61.5%) generated a sustained detrusor contraction generating a void, with a median peak voiding pressure of 38 cm H20 (IQR: 28-51). The median bladder capacity reached was 48 ml, which represented a median of 30% of expected bladder capacity. The median post void residual (PVR) for the entire cohort was 26 ml (IQR: 9, 47) or 51% (IQR: 20%-98%) of their actual bladder capacity, while the median PVR for those children with a sustained detrusor contraction was 18 ml (IQR: 5, 46) or 33% (IQR: 27%, 98%) of their actual bladder capacity. Intraoperative bladder width and bladder dome to bladder neck length did not correlate with the presence of voiding via a detrusor contraction (p = 0.64).

DISCUSSION

We present the first study assessing early UDS finding of detrusor contraction in BE patients after CPRE. In our cohort, 61.5% of patients were able to generate a sustained detrusor contraction on UDS which is a higher percentage than has been reported in previous series. A difference in initial surgical management may account for these findings.

CONCLUSION

At short term follow up, the majority of children in our cohort were able to produce sustained detrusor contractions sufficient to generate a void per urethra with a modest post void residual volume. Long-term follow-up and repeated UDS will be needed to track detrusor contractility rates, bladder capacities, compliance, post void residuals and ultimately continence rates over time.

Abstract 2780: Unique pharmacodynamic properties conferred by differential binding to BTK, pirtobrutinib vs covalent inhibitors

Covalent Bruton tyrosine kinase inhibitors (cBTKi) have transformed the treatment of B cell malignancies. Despite the efficacy of cBTKi, treatment failure often occurs through development of resistance or intolerance. Pirtobrutinib, a highly selective, non-covalent BTKi, potently inhibits both WT and C481 mutant BTK. Pirtobrutinib has favorable oral pharmacology, is well tolerated, and has shown promising efficacy in patients with poor prognosis B cell malignancies following prior therapy, including prior cBTKi. Here we report in vitro BTK binding, conformation, and activation differences between cBTKi and pirtobrutinib. Cellular studies showed pirtobrutinib inhibited BTK phosphorylation at both Y223 and Y551 in REC-1 and Ramos A1 human lymphoma cell lines. In contrast, despite inhibition of Y223 phosphorylation, both cell lines treated with cBTKi, ibrutinib, acalabrutinib or zanubrutinib, retained Y551 phosphorylation. The differential effects on Y551 were also observed in PBMC isolated from treatment naïve human CLL donors treated in vitro with pirtobrutinib or ibrutinib. To investigate the binding effects of cBTKi and pirtobrutinib on BTK stability and conformation, a series of biophysical and structural studies were performed. In a hydrogen/deuterium exchange mass spectrometry study using full length BTK, all compounds significantly inhibited exchange in regions surrounding the ATP binding site in the kinase domain. While cBTKi induced significantly increased exchange for peptides in the SH3 and SH2 domains, pirtobrutinib significantly reduced exchange in a portion of the SH3 domain, nearly the entire SH2 domain, and SH2 linker, suggesting that pirtobrutinib uniquely stabilizes BTK in a closed/inactive conformation. Consistent with this proposed model, crosslinking mass spectrometry results of inhibitor bound BTK showed that pirtobrutinib promoted different interactions between the SH2 domain and kinase domain than cBTKi. To confirm that pirtobrutinib promotes greater stabilization of BTK, a mass spectrometry based cellular thermal shift assay was performed in both Ramos and BTK overexpressing HEK293 cells. In both cell lines, pirtobrutinib showed significantly greater stabilization of BTK compared to cBTKi. In addition, crystallographic studies of BTK in complex with pirtobrutinib revealed domain organization consistent with stabilized SH2-SH3 interactions with the kinase domain. These data suggest pirtobrutinib may differentially impact BTK stability and conformation compared to cBTKi. The cellular and biophysical data are consistent with a model in which cBTKi shift BTK toward an open conformation, whereas pirtobrutinib allosterically stabilizes a closed BTK conformation, preventing activation by upstream kinases. Additional studies are underway to further characterize the differential effects of pirtobrutinib on BTK conformation.

Citation Format: Joshua A. Ballard, Kevin Ebata, Hetal S. Randeria, Garrett Tinline, Thomas Lee, Lauren M. Hanson, John A. Latham, E. Peder Cedervall, Jenny Chong, Kyle B. Del Valle, Bernard C. Collins, Tony H. Morales, Thomas C. Benedict, Marc A. Schureck, Ethan T. Bender, Christopher Mendoza, David Molina, Meagan Nakamoto, Hsiao-Chiao Shiah, Hao Xu, Alfonso Espada, Leticia Cano, Charles K. Allerston, Paul Schnier, Barbara J. Brandhuber. Unique pharmacodynamic properties conferred by differential binding to BTK, pirtobrutinib vs covalent inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2780.

Broadly neutralizing aptamers to SARS-CoV-2: A diverse panel of modified DNA antiviral agents

Since its discovery, COVID-19 has rapidly spread across the globe and has had a massive toll on human health, with infection mortality rates as high as 10%, and a crippling impact on the world economy. Despite numerous advances, there remains an urgent need for accurate and rapid point-of-care diagnostic tests and better therapeutic treatment options. To contribute chemically distinct, non-protein-based affinity reagents, we report here the identification of modified DNA-based aptamers that selectively bind to the S1, S2, or receptor-binding domain of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein. Several aptamers inhibit the binding of the spike protein to its cell-surface receptor angiotensin-converting enzyme 2 (ACE2) and neutralize authentic SARS-CoV-2 virus in vitro, including all variants of concern. With a high degree of nuclease resistance imparted by the base modifications, these reagents represent a new class of molecules with potential for further development as diagnostics or therapeutics.

Facilitating the structural characterisation of non-canonical amino acids in biomolecular NMR

Peptides and proteins containing non-canonical amino acids (ncAAs) are a large and important class of biopolymers. They include non-ribosomally synthesised peptides, post-translationally modified proteins, expressed or synthesised proteins containing unnatural amino acids, and peptides and proteins that are chemically modified. Here, we describe a general procedure for generating atomic descriptions required to incorporate ncAAs within popular NMR structure determination software such as CYANA, CNS, Xplor-NIH and ARIA. This procedure is made publicly available via the existing Automated Topology Builder (ATB) server (https://atb.uq.edu.au, last access: 17 February 2023) with all submitted ncAAs stored in a dedicated database. The described procedure also includes a general method for linking of side chains of amino acids from CYANA templates. To ensure compatibility with other systems, atom names comply with IUPAC guidelines. In addition to describing the workflow, 3D models of complex natural products generated by CYANA are presented, including vancomycin. In order to demonstrate the manner in which the templates for ncAAs generated by the ATB can be used in practice, we use a combination of CYANA and CNS to solve the structure of a synthetic peptide designed to disrupt Alzheimer-related protein-protein interactions. Automating the generation of structural templates for ncAAs will extend the utility of NMR spectroscopy to studies of more complex biomolecules, with applications in the rapidly growing fields of synthetic biology and chemical biology. The procedures we outline can also be used to standardise the creation of structural templates for any amino acid and thus have the potential to impact structural biology more generally.

PyThinFilm: Automated Molecular Dynamics Simulation Protocols for the Generation of Thin Film Morphologies

The performance of organic optoelectronic devices, such as organic light-emitting diodes (OLEDs) and organic solar cells (OSCs), is intrinsically related to the molecular-scale morphology of the thin films from which they are composed. However, the experimental characterization of morphology at the molecular level is challenging due to the often amorphous or at best semicrystalline nature of these films. Classical molecular modeling techniques, such as molecular dynamics (MD) simulation, are increasingly used to understand the relationship between morphology and the properties of thin-film devices. PyThinFilm (github.com/ATB-UQ/PyThinFilm) is an open-source Python package which allows fully automated MD simulations of thin film growth to be performed using vacuum and/or solution deposition processes. PyThinFilm utilizes the GROMACS simulation package in combination with interaction parameters from the Automated Topology Builder (atb.uq.edu.au). Here, PyThinFilm is described along with an overview of applications in which PyThinFilm has been used to study the thin films of organic semiconductor materials typically used in OLEDs and OSCs.

Intraarticular steroids as DMARD-sparing agents for juvenile idiopathic arthritis flares: Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) who achieve a drug free remission often experience a flare of their disease requiring either intraarticular steroids (IAS) or systemic treatment with disease modifying anti-rheumatic drugs (DMARDs). IAS offer an opportunity to recapture disease control and avoid exposure to side effects from systemic immunosuppression. We examined a cohort of patients treated with IAS after drug free remission and report the probability of restarting systemic treatment within 12 months.

METHODS

We analyzed a cohort of patients from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry who received IAS for a flare after a period of drug free remission. Historical factors and clinical characteristics and of the patients including data obtained at the time of treatment were analyzed.

RESULTS

We identified 46 patients who met the inclusion criteria. Of those with follow up data available 49% had restarted systemic treatment 6 months after IAS injection and 70% had restarted systemic treatment at 12 months. The proportion of patients with prior use of a biologic DMARD was the only factor that differed between patients who restarted systemic treatment those who did not, both at 6 months (79% vs 35%, p < 0.01) and 12 months (81% vs 33%, p < 0.05).

CONCLUSION

While IAS are an option for all patients who flare after drug free remission, it may not prevent the need to restart systemic treatment. Prior use of a biologic DMARD may predict lack of success for IAS. Those who previously received methotrexate only, on the other hand, are excellent candidates for IAS.

Proximalization through one incision of a wrist arteriovenous fistula and distal revascularization with interval ligation

In the setting of ischemic steal syndrome with tissue loss, patients with radiocephalic fistulas have limited options to preserve their conduit and treat their ischemic symptoms. To address this, we have proposed the technique of proximalization through one incision of a wrist arteriovenous fistula (POWR) with distal revascularization with interval ligation (DRIL) procedure. In the present retrospective, single-center, case series, we evaluated the outcomes of three patients with radiocephalic fistulas who had undergone POWR DRIL from 2017 to 2021. Their ischemic symptoms were monitored for regression. All three patients showed signs of regressing ischemia. The POWR DRIL represents an efficient procedure to address tissue loss and preserve the autogenous conduit.

Is Online Video-Based Education an Effective Method to Teach Basic Surgical Skills to Students and Surgical Trainees? A Systematic Review and Meta-analysis

BACKGROUND

Online education has been increasingly utilized over the past decades. The COVID-19 pandemic accelerated the transition of conventional face-to-face curricula to online platforms, with limited evidence for its teaching efficacy. This systematic review aims to assess the effectiveness of online video-based education compared with standard conventional education in teaching basic surgical skills to surgical trainees and students undergoing medical training.

METHODS

We performed a literature search in Embase, Medline, Cochrane CENTRAL and Scopus from inception until February 2022. Studies included were randomised controlled trials (RCTs) and observational studies. We included randomised controlled trials only for meta-analysis. The primary outcome was surgical skill proficiency. The secondary outcomes were participant perception, confidence and satisfaction. Two authors independently assessed the search results for eligibility, extracted the data and assessed the risk of bias using the Cochrane Risk of Bias tool 2. Where appropriate, we performed random effects meta-analyses of the pooled study data to calculate a standardized mean difference.

RESULTS

A total of 11 studies met the inclusion criteria totaling 715 participants; 603 were included in qualitative analysis and 380 in meta-analysis. All included studies were assessed as having a low risk of bias. The majority of studies found no significant difference between conventional and video-based education in teaching basic surgical skills, three studies found video-based education was superior and one study found conventional education was superior. There was no statistically significant difference in skill proficiency between the two groups (standardized mean difference of -0.02 (95% CI: -0.34, 0.30); p=0.90). Video-based education results in an equivalent improvement in confidence and satisfaction rates. Additional benefits of video-based education include convenience, accessibility and efficiency.

CONCLUSIONS

Basic surgical skills can be taught as effectively through online video-based education as conventional teaching methods. Online education should be utilized as an adjunct to medical curricula beyond the COVID-19 era.

The I4RON-HF study, Intravenous Iron Isomaltoside for Inpatients veRsus Outpatient Asians with Heart Failure

Background and purpose

Iron deficiency (ID) impacts ∼50% of heart failure (HF) patients [1] and is a risk factor and strong predictor for death and mortality with or without anaemia [2]. Oral iron appears to be ineffective whilst intravenous iron (IV-iron) has proven to be efficacious however data is primarily from a Caucasian population [3] despite ID being more prevalent amongst Asians. The I4RON-HF study assesses efficacy of high-dose IV-iron versus oral iron in stable outpatients and inpatients amongst an Asian population recovering from episodes of decompensated HF.

Methods

This is a single-centre randomized controlled study, where patients who had symptomatic heart failure (Ejection Fraction &lt;50% and New York Heart Association class 2–3) were randomized into two groups. The intervention arm received anywhere from 500mg to 1500mg of IV Iron Isomaltoside as a single infusion, whereas the control arm received routine iron supplements.

The primary study endpoint was the percentage of patients achieving iron repletion at 4,8 and 12 months after enrolment. Secondary endpoints included clinical parameters (6-minute walk test, NYHA status and 2D-Echocardiogram), and biochemical parameters (Serum NTproBNP, Cardiac Troponin-T and hemogloblin) at 4,8 and 12 months.

Results

A total of 65 patients were enrolled (male 55%), 33 in the interventional arm and 32 in the control arm. There were no patients lost to follow up. 96.9% of patients in the IV Iron arm achieved the primary endpoint at 4 months, compared to 68.7% in the control group. These findings we consistent at 8 months (90.9% vs 65.6%) and 12 months (90.9% vs 56.2%). Looking at the secondary endpoints, the IV Iron cohort recorded a 11.14% increase in Hemogloblin levels versus the control arm which recorded a reduction of 16.23%. There was also lower NTproBNP levels in the IV iron group (81.6% reduction) versus the control group (66.3% reduction). Clinically, the patients who received IV iron had a 42.98% increase in their 6-minute walk test from baseline, compared to an increase of 8.61% in the control arm. There were no significant echocardiographic changes.

Conclusion

These findings in our single-centre study support the efficacy of IV iron over oral supplements in the treatment of iron deficiency amongst Asian heart failure patients. The secondary endpoints also indicate better clinical and biochemical outcomes when iron stores are successfully repleted. Lastly, this study demonstrates the feasibility and safety of outpatient administration of high-dose IV-iron. Results from large-scale clinical studies looking at hard endpoints (mortality, HF hospitalization) are expected to further advance understandings.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): National Heart Institute (Institut Jantung Negara) FoundationCompai Pharma

Association of malnutrition with in-hospital and long-term outcomes among ST-elevation myocardial infarction patients receiving primary PCI

Background

The impact of malnutrition on outcomes in a contemporary ST-segment-elevation myocardial infarction (STEMI) population is unclear. We hypothesized that malnutrition severity amongst STEMI patients undergoing primary percutaneous coronary intervention (pPCI) is associated with worse long-term outcomes.

Purpose

The aim of this study was 2-fold: 1) to establish the prevalence of malnutrition among STEMI patients undergoing pPCI; 2) to determine the association of malnutrition severity on in-hospital and 1-year outcomes in STEMI patients receiving pPCI

Methods

We retrospectively identified 1,169 STEMI patients of age ≥65 years who had received pPCI (2013–2020). Patients who had presented with out-of-hospital cardiac arrest or those who received fibrinolytic therapy were excluded. The Controlling Nutritional Status (CONUT) score, based on serum albumin, total cholesterol and lymphocyte count, was used as a tool to assess the nutritional status of included patients. Malnourished patients were defined as those with a CONUT score of 5 to 12. To account for the impact of frailty, a frailty index (FI) was determined using the health deficit accumulation model (Table 1). The primary outcome was 1-year all-cause mortality. The secondary outcome was a composite of in-hospital heart failure, cardiogenic shock, re-infarction, major bleeding, stroke, and all-cause mortality. A multivariable model adjusting for baseline covariates, including frailty index score, was performed (Figure 1).

Results

Among 1,169 STEMI patients receiving pPCI, 315 (26.9%) were classified as malnourished. Malnourished patients were older (mean 77.4 vs. 76.0 years, p=0.009) and had a higher comorbidity burden. After multivariable adjustment, worsening malnutrition was associated with increased 1-year all-cause mortality (odds ratio [OR] = 1.29, p&lt;0.001). Worsening malnutrition was also associated with a higher incidence of the in-hospital composite adverse outcome (OR = 1.12, p=0.003) and increased in-hospital all-cause mortality (OR=1.41, p&lt;0.001).

Conclusion

Among STEMI patients receiving pPCI, 1 in 4 were malnourished. Malnutrition was associated with increased rate of in-hospital composite adverse outcome and worse long-term outcomes, even when accounting for frailty. Efforts to routinely identify malnourished STEMI patients and to implement best practices to reduce the risk of adverse events in this vulnerable population are warranted.

Funding Acknowledgement

Type of funding sources: None.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Using a Facebook Virtual Examination Room to Enhance ROP Training in Armenia

Purpose

Retinopathy of prematurity (ROP) is a leading cause of worldwide childhood blindness with increasing incidence in low and middle income countries (LMICs) due to advances in neonatal care. There are insufficient numbers of healthcare professionals specialized in ROP management and few local training opportunities in LMICs. Social media platforms provide a promising solution to enable interactive medical education across geographic and logistic barriers. As an adjunct to an ROP training program for ophthalmologists in Armenia, we implemented a Facebook Virtual Examination Room (VER) for case discussion with a global community of collaborators and preceptors. To evaluate training through VER, we operationalized engagement as a multilayer meta-construct that includes cognitive, behavioral, and social-emotional domains.

Methods

A concurrent mixed methods approach was taken to collect and analyze data from comments and activities within VER. Quantitative data was analyzed for descriptive statistics on group utilization, participant activity, and clinical metrics. Qualitative data was analyzed by conducting thematic analysis involving initial and pattern coding.

Results

Ten participants (7 trainees and 3 preceptors) interacted in the Facebook group across 153 unique cases, with 218 threads, 414 comments, and 216 likes. Of the 120 unique cases eligible for consensus evaluation, treatment was mentioned most frequently (87), followed by location (68), staging (65), and plus disease (31), with agreement ranging from 67% to 97%. Based on the qualitative analysis, the most common themes of discussion were clinical management, dilemma resolution, knowledge growth, and gratitude.

Conclusion

A closed Facebook group for case-based discussions can be a useful adjunct to an existing ROP training program by engaging learners across social-emotional, behavioral, and cognitive domains. For international training partnerships, the financial and logistical advantages can be significant, though focus should remain on the primary curriculum and training modality.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Taf2 mediates DNA binding of Taf14

The assembly and function of the yeast general transcription factor TFIID complex requires specific contacts between its Taf14 and Taf2 subunits, however, the mechanism underlying these contacts remains unclear. Here, we determined the molecular and structural basis by which the YEATS and ET domains of Taf14 bind to the C-terminal tail of Taf2 and identified a unique DNA-binding activity of the linker region connecting the two domains. We show that in the absence of ligands the linker region of Taf14 is occluded by the surrounding domains, and therefore the DNA binding function of Taf14 is autoinhibited. Binding of Taf2 promotes a conformational rearrangement in Taf14, resulting in a release of the linker for the engagement with DNA and the nucleosome. Genetic in vivo data indicate that the association of Taf14 with both Taf2 and DNA is essential for transcriptional regulation. Our findings provide a basis for deciphering the role of individual TFIID subunits in mediating gene transcription.