Comprehensive Impurity Profiling of mRNA: Evaluating Current Technologies and Advanced Analytical Techniques.

In vitro transcription (IVT) of mRNA is a versatile platform for a broad range of biotechnological applications. Its rapid, scalable, and cost-effective production makes it a compelling choice for the development of mRNA-based cancer therapies and vaccines against infectious diseases. The impurities generated during mRNA production can potentially impact the safety and efficacy of mRNA therapeutics, but their structural complexity has not been investigated in detail yet. This study pioneers a comprehensive profiling of IVT mRNA impurities, integrating current technologies with innovative analytical tools. We have developed highly reproducible, efficient, and stability-indicating ion-pair reversed-phase liquid chromatography and capillary gel electrophoresis methods to determine the purity of mRNA from different suppliers. Furthermore, we introduced the applicability of microcapillary electrophoresis for high-throughput (<1.5 min analysis time per sample) mRNA impurity profiling. Our findings revealed that impurities are mainly attributed to mRNA variants with different poly(A) tail lengths due to aborted additions or partial hydrolysis and the presence of double-stranded mRNA (dsRNA) byproducts, particularly the dsRNA 3'-loop back form. We also implemented mass photometry and native mass spectrometry for the characterization of mRNA and its related product impurities. Mass photometry enabled the determination of the number of nucleotides of different mRNAs with high accuracy as well as the detection of their size variants [i.e., aggregates and partial and/or total absence of the poly(A) tail], thus providing valuable information on mRNA identity and integrity. In addition, native mass spectrometry provided insights into mRNA intact mass, heterogeneity, and important sequence features such as poly(A) tail length and distribution. This study highlights the existing bottlenecks and opportunities for improvement in the analytical characterization of IVT mRNA, thus contributing to the refinement and streamlining of mRNA production, paving the way for continued advancements in biotechnological applications.

Analytical and Functional Characterization of Plasmid DNA Topological Forms and Multimers.

Plasmid DNA (pDNA) is an essential tool in genetic engineering that has gained prevalence in cell and gene therapies. Plasmids exist as supercoiled (SC), open circular (OC), and linear forms. Plasmid multimerization can also occur during the manufacturing process. Even though the SC forms are thought to provide optimal knock-in (KI) efficiency, there is no strong consensus on the effect of the topological forms and multimers on the functional activity. In addition, the results obtained for conventional pDNAs (>5 kbp) do not necessarily translate to smaller pDNAs (∼3 kbp). In this study, a workflow was developed for the analytical and functional characterization of pDNA topological forms and multimers. An anion exchange chromatography (AEC) method was first developed to quantify the topological forms and multimers. Four AEC columns were initially compared, one of which was found to provide superior chromatographic performance. The effect of mobile phase pH, various salts, column temperature, and acetonitrile content on the separation performance was systematically studied. The method performance, including precision and accuracy, was evaluated. The final AEC method was compared to capillary gel electrophoresis (CGE) by analyzing several pDNA sequences and lots. A forced degradation study revealed unexpectedly high degradation of the SC forms. Finally, the KI efficiency was compared for the SC and OC forms, and the multimers.

Use of artificial intelligence-guided echocardiography to detect cardiac dysfunction and heart valve disease in rural and remote areas: Rationale and design of the AGILE-echo trial.

BACKGROUND: Transthoracic echocardiography (TTE) is essential in the diagnosis of cardiovascular diseases (CVD), including but not limited to heart failure (HF) and heart valve disease (HVD). However, its dependence on expert acquisition means that its accessibility in rural areas may be limited, leading to delayed management decisions and potential missed diagnoses. Artificial intelligence-guided (AI)-TTE offers a solution by permitting non-expert image acquisition. The impact of AI-TTE on the timing of diagnosis and early initiation of cardioprotection is undefined. METHODS: AGILE-Echo (use of Artificial intelligence-Guided echocardiography to assIst cardiovascuLar patient managEment) is a randomized-controlled trial conducted in 5 rural and remote areas around Australia. Adults with CV risk factors and exercise intolerance, or concerns regarding HVD are randomized into AI-TTE or usual care (UC). AI-TTE participants may have a cardiovascular problem excluded, identified (leading to AI-guided interventions) or unresolved (leading to conventional TTE). UC participants undergo usual management, including referral for standard TTE. The primary endpoint is a composite of HVD or HF diagnosis at 12-months. Subgroup analysis, stratified based on age range and sex, will be conducted. All statistical analyses will be conducted using R. RESULTS: Of the first 157 participants, 78 have been randomized into AI-TTE (median age 68 [IQR 17]) and 79 to UC (median age 65 [IQR 17], P = .034). HVD was the primary concern in 37 participants (23.6%) while 84.7% (n = 133) experienced exercise intolerance. The overall 10-year HF incidence risk was 13.4% and 20.0% (P = .089) for UC and AI-TTE arm respectively. Atrial remodeling, left ventricular remodeling and valvular regurgitation were the most common findings. Thirty-three patients (42.3%) showed no abnormalities. CONCLUSIONS: This randomized-controlled trial of AI-TTE will provide proof-of-concept for the role of AI-TTE in identifying pre-symptomatic HF or HVD when access to TTE is limited. Additionally, this could promote the usage of AI-TTE in rural or remote areas, ultimately improving health and quality of life of community dwelling adults with risks, signs or symptoms of cardiac dysfunction.

Restoring microvascular circulation with diagnostic ultrasound and contrast agent: rationale and design of the REDUCE trial.

OBJECTIVES: This study aims to evaluate the efficacy and cost-effectiveness of sonothrombolysis delivered pre and post primary percutaneous coronary intervention (pPCI) on infarct size assessed by cardiac MRI, in patients presenting with STEMI, when compared against sham procedure. BACKGROUND: More than a half of patients with successful pPCI have significant microvascular obstruction and residual infarction. Sonothrombolysis is a therapeutic use of ultrasound with contrast enhancement that may improve microcirculation and infarct size. The benefits and real time physiological effects of sonothrombolysis in a multicentre setting are unclear. METHODS: The REDUCE (Restoring microvascular circulation with diagnostic ultrasound and contrast agent) trial is a prospective, multicentre, patient and outcome blinded, sham-controlled trial. Patients presenting with STEMI will be randomized to one of 2 treatment arms, to receive either sonothrombolysis treatment or sham echocardiography before and after pPCI. This tailored design is based on preliminary pilot data from our centre, showing that sonothrombolysis can be safely delivered, without prolonging door to balloon time. Our primary endpoint will be infarct size assessed on day 4±2 on Cardiac Magnetic Resonance (CMR). Patients will be followed up for 6 months post pPCI to assess secondary endpoints. Sample size calculations indicate we will need 150 patients recruited in total. CONCLUSIONS: This multicentre trial will test whether sonothrombolysis delivered pre and post primary PCI can improve patient outcomes and is cost-effective, when compared with sham ultrasound delivered with primary PCI. The results from this trial may provide evidence for the utilization of sonothrombolysis as an adjunct therapy to pPCI to improve cardiovascular outcomes in STEMI. ANZ Clinical Trial Registration number: ACTRN 12620000807954.

Prophylaxis to Prevent Cardiotoxicity in Patients Receiving Anthracycline for Breast Cancer: A Combined Bayesian and Frequentist Network Meta-Analysis of Randomised Controlled Trials.

BACKGROUND: The benefits in survivorship gained with anthracycline (ANT)-based chemotherapies for breast cancer are unfortunately mitigated for some patients by irreversible cardiotoxicity. Randomised controlled trials (RCTs) have explored multiple cardioprotection options, however, it remains unclear which drug is most effective in preserving left ventricular ejection fraction (LVEF). This study aimed to perform a systematic review and network meta-analysis, using Bayesian and frequentist approaches, of RCTs evaluating cardioprotective agents. METHODS: Two authors searched four databases (CENTRAL, Cochrane Reviews, MEDLINE, SCOPUS), to find RCTs evaluating cardioprotective agents. Trial populations were limited to patients with breast cancer without prior ANT exposure. The primary outcome was mean LVEF change pre and post ANT dosing. Our primary analysis utilised a Bayesian approach, while our sensitivity analysis used frequentist methodology (Prospero registration number CRD42020199580). RESULTS: From 4,007 search results, we identified 12 RCTs, with their various trial arms considered separately-nine beta-blocker (BB), two angiotensin-converting enzyme inhibitor /angiotensin receptor blockers [(AA)+BB=AABB], one AA, one spironolactone, one statin-evaluating 1,126 patients (age 50.5 years). Bayesian network meta-analysis showed no difference in LVEF preservation between AA (1.3%, 95% credible interval [-0.20, 2.9]), BB (0.77, [-0.21, 1.8]), AABB (0.84 [-1.1, 2.8]), spironolactone (0.72, [-2.3, 3.7]) or statin (0.60, [-2.4, 3.6]) when compared against placebo. However, the frequentist analysis showed benefits from using AA (mean difference, 1.32% [0.32, 2.33]) and BB (mean difference, 0.76% [0.12, 1.4]). CONCLUSIONS: There is insufficient evidence to support prophylactic cardioprotection to prevent EF reduction. However, frequentist analysis suggested that AA or BBs provide cardioprotection. Thus, for those already on other anti-hypertensives, switching to AA or BBs could be considered.

Rationale and Design of the Cessation Of Pharmacotherapy In Recovered Chemotherapy-induced cardioToxicity (COP-RCT): A Pilot Study.

BACKGROUND: Cancer therapeutics-related cardiac dysfunction (CTRCD) is a well-recognised complication of cancer treatment. Treatment of CTRCD involves cardioprotective therapy (CPT) which can lead to a recovery of CTRCD with normalisation of the left ventricular ejection fraction (LVEF). As a result, there are potentially millions of cancer survivors with recovered CTRCD on CPT. Cardioprotective therapy can be associated with an undesirable long-term pill burden, financial costs, and side effects. Cancer survivorship is anticipated to increase significantly by the end of this decade. To date, there is no evidence of the safety of stopping CPT in this setting. This study seeks to evaluate the hypothesis that ceasing cardioprotective medication is a feasible and safe option without significant impact on LVEF in low-risk patients who have recovered from CTRCD. METHODS AND ANALYSIS: We will perform a multicentre prospective open-label randomised controlled trial with blinded endpoint (PROBE) of supervised CPT cessation compared to continuing CPT (control). The primary study end point is the change in LVEF by cardiac magnetic resonance imaging at 6 months of enrolment between the two groups. Secondary end points include changes in quality-of-life questionnaires, other cardiac imaging parameters, and recurrence of heart failure. CONCLUSION: Cessation Of Pharmacotherapy In Recovered Chemotherapy-induced cardioToxicity (COP-RCT) is one of the first studies currently underway to evaluate the safety of ceasing CPT in recovered CTRCD. The results will inform clinical practice in this evidence-free zone.

Long-Term Follow-Up of Mortality and Heart Failure Hospitalisation in Patients With Intracardiac Device-Related Tricuspid Regurgitation.

INTRODUCTION: Tricuspid regurgitation (TR) is a known complication of cardiac implantable electronic devices (CIED). A better understanding of the patient population affected by this complication and their outcomes is needed. The aims of our study were to: 1) describe the incidence of CIED-related tricuspid regurgitation; 2) identify patient characteristics conferring risk; 3) assess the long-term risk of hospitalisation for heart failure and mortality in patients with this complication. METHODS: This was a retrospective cohort study of 2,265 patients that had a de novo device implantation at a tertiary referral centre between January 2010 and December 2017. Patients with echocardiograms prior to and at least 3 months after device implantation were included. Patients with moderate or severe TR at baseline were excluded. RESULTS: Following screening of medical records, 165 patients were analysed. Forty-four (44) (27%) patients developed new-onset moderate or severe device-related TR, without a significant difference between patients with permanent pacemaker (PPM) and implantable cardioverter-defibrillator (ICD). Patients with CIED-related tricuspid regurgitation had a higher rate of hospitalisation for heart failure than those without (63.6% vs 34.7%, p=0.001) during a median follow-up of 29 months (IQR 13-60 months). Subsequent analyses showed that the association between CIED-related TR and heart failure hospitalisation only became significant in the period beyond 12 months following CIED implantation. Piecewise Cox regression analysis stratified at 12 months of follow-up showed that CIED-related TR was associated with an increased risk of heart failure hospitalisation beyond 12 months after adjustment for differences in baseline characteristics (HR 1.99, 95% CI 1.05-3.76, p=0.03). There was a higher mortality rate in the group with CIED-related TR; however, this did not reach significance (36.3% vs 22.3%, p=0.09). CONCLUSION: CIED-related TR is common and clinically significant with serious implications for long-term outcomes, especially congestive heart failure.

Predictive In Vitro Vitreous and Serum Models and Methods to Assess Thiol-Related Quality Attributes in Protein Therapeutics.

In vitro models that mimic the in vivo environment can greatly facilitate and support criticality assessment of product quality attributes for therapeutic drugs to ensure product quality. An in vitro model is established to study and predict the impact of thiol-related attributes on safety or efficacy of intraocular antibody products. This model simulates the physiological redox environment of rabbit vitreous and maintains a steady-state redox potential using reduced and oxidized forms of glutathione. A similar in vitro model that mimics the thiol redox conditions of human blood has been previously established and has become a predictive tool to study intravenous (IV) therapeutic proteins. We utilized both vitreous and serum models to study the potential impact of antibody variants (trisulfides and free-thiols) on product qualities of different antibodies. The studies demonstrate that both models are effective tools to monitor changes of thiol-related attributes under physiological conditions, providing insights on these thiol-related attributes and allowing for more informed assessment of biological relevance and criticality of the attributes. Furthermore, we propose that the approach using an in vitro study for the product quality attribute assessment can be used to predict in vivo effects for future molecules during the development of biopharmaceuticals, reducing the need for live subject studies.

Mining the Stiffness-Sensitive Transcriptome in Human Vascular Smooth Muscle Cells Identifies Long Noncoding RNA Stiffness Regulators.

OBJECTIVE: Vascular extracellular matrix stiffening is a risk factor for aortic and coronary artery disease. How matrix stiffening regulates the transcriptome profile of human aortic and coronary vascular smooth muscle cells (VSMCs) is not well understood. Furthermore, the role of long noncoding RNAs (lncRNAs) in the cellular response to stiffening has never been explored. This study characterizes the stiffness-sensitive (SS) transcriptome of human aortic and coronary VSMCs and identifies potential key lncRNA regulators of stiffness-dependent VSMC functions. APPROACH AND RESULTS: Aortic and coronary VSMCs were cultured on hydrogel substrates mimicking physiological and pathological extracellular matrix stiffness. Total RNAseq was performed to compare the SS transcriptome profiles of aortic and coronary VSMCs. We identified 3098 genes (2842 protein coding and 157 lncRNA) that were stiffness sensitive in both aortic and coronary VSMCs (false discovery rate <1%). Hierarchical clustering revealed that aortic and coronary VSMCs grouped by stiffness rather than cell origin. Conservation analyses also revealed that SS genes were more conserved than stiffness-insensitive genes. These VSMC SS genes were less tissue-type specific and expressed in more tissues than stiffness-insensitive genes. Using unbiased systems analyses, we identified MALAT1 as an SS lncRNA that regulates stiffness-dependent VSMC proliferation and migration in vitro and in vivo. CONCLUSIONS: This study provides the transcriptomic landscape of human aortic and coronary VSMCs in response to extracellular matrix stiffness and identifies novel SS human lncRNAs. Our data suggest that the SS transcriptome is evolutionarily important to VSMCs function and that SS lncRNAs can act as regulators of stiffness-dependent phenotypes.

A Rapid Access Chest Pain Clinic (RACPC): Initial Australian Experience.

BACKGROUND: Chest pain is the second most common presenting symptom to emergency departments (ED) in Australia, although up to 85% of these patients do not have an acute coronary syndrome (ACS). Cardiologist-led rapid access chest pain clinics (RACPC) have been proposed overseas to assist in the management of such patients, with prompt outpatient assessment if patients are deemed low risk and discharged from the ED. The use of RACPCs in Australia has been only recently proposed; we therefore sought to examine one such RACPC in an Australian context. METHODS AND RESULTS: 1133 consecutive patients were seen at a metropolitan RACPC, between August 2008 and February 2017. There was a high preponderance of cardiovascular risk factors. Exercise stress testing (EST) was the default investigation upon discharge from ED, with a total of 1038 ESTs performed in 1113 patients (93%), with low numbers of other functional tests, and a small, but increasing number of coronary computed tomography (CT) scans performed over this period. Eighteen patients subsequently underwent revascularisation (1.6% of the total cohort), and none of these patients were readmitted at any time with an ACS between the interval of their index ED presentation to these investigations or treatments. Five (0.4%) patients represented to ED within 48hours, none due to a cardiovascular cause. A total of 24 (2.1%) patients represented between 2 and 28 days, with none of these due to an ACS. CONCLUSIONS: Following ED assessment of acute chest pain as low risk-with direct ED referral for exercising testing followed by RACPC review-results in very low readmission rates at 48hours and at 28 days. Moreover, these readmissions were almost always not of cardiovascular aetiology, and occurred despite relatively longer waiting periods for both EST (8 days) and between EST and RACPC review (11 days), than the prespecified 72 to 96hours as defined by the clinic protocol. Further investigation into this model of care in Australia is suggested.

Host cell protein testing by ELISAs and the use of orthogonal methods.

Host cell proteins (HCPs) are among the process-related impurities monitored during recombinant protein pharmaceutical process development. The challenges of HCP detection include (1) low levels of residual HCPs present in large excess of product protein, (2) the assay must measure a large number of different protein analytes, and (3) the population of HCP species may change during process development. Suitable methods for measuring process-related impurities are needed to support process development, process validation, and control system testing. A multi-analyte enzyme-linked immunosorbent assay (ELISA) is the workhorse method for HCP testing due to its high throughput, sensitivity and selectivity. However, as the anti-HCP antibodies, the critical reagents for HCP ELISA, do not comprehensively recognize all the HCP species, it is especially important to ensure that weak and non-immunoreactive HCPs are not overlooked by the ELISA. In some cases limited amount of antibodies to HCP species or antigen excess causes dilution-dependent non-linearity with multi-product HCP ELISA. In our experience, correct interpretation of assay data can lead to isolation and identification of co-purifying HCP with the product in some cases. Moreover, even if the antibodies for a particular HCP are present in the reagent, the corresponding HCP may not be readily detected in the ELISA due to antibody/antigen binding conditions and availability of HCP epitopes. This report reviews the use of the HCP ELISA, discusses its limitations, and demonstrates the importance of orthogonal methods, including mass spectrometry, to complement the platform HCP ELISA for support of process development. In addition, risk and impact assessment for low-level HCPs is also outlined, with consideration of clinical information.

Coronary Flow Velocity Reserve Declines After Anthracycline Therapy in Breast Cancer Patients.

Anthracycline therapy (ANT) is associated with cancer therapy-related cardiac dysfunction. Coronary flow velocity reserve (CFVR) has shown prognostic utility in non-cancer cohorts, but no data have been obtained in a cardio-oncology setting. We investigated the acute effect of ANT on CFVR in breast cancer patients. A total of 12 female breast cancer patients undergoing ANT had pre- and post-ANT CFVR assessment. A significant decline in CFVR occurred (baseline: 2.66 ± 0.41 vs post-ANT: 2.47 ± 0.37, P = 0.016). This prospective study is the first to identify ANT-related coronary physiology changes in humans. Further studies are required to determine their clinical significance.

Le traitement par l'anthracycline est associé à une dysfonction cardiaque liée au traitement anticancéreux. La réserve de débit coronaire a démontré son utilité pronostique dans les cohortes sans cancer, mais aucune donnée n'a été obtenue dans un contexte de cardio-oncologie. Nous avons étudié l'effet aigu de l'anthracycline sur la réserve de débit coronaire chez des patientes atteintes d'un cancer du sein. La réserve de débit coronaire a été évaluée avant et après le traitement par l'anthracycline chez un total de 12 femmes atteintes d'un cancer du sein. Un déclin important de la réserve de débit coronaire est survenu (valeur initiale de 2,66 ± 0,41 par rapport à 2,47 ± 0,37 après le traitement par l'anthracycline, p = 0,016). Cette étude prospective est la première à déceler des changements dans la physiologie coronarienne liés à l'anthracycline chez les humains. D'autres études sont nécessaires pour en déterminer la portée clinique.

Sonothrombolysis Before and After Percutaneous Coronary Intervention Provides the Largest Myocardial Salvage in ST Segment Elevation Myocardial Infarction.

BACKGROUND: Sonothrombolysis is a therapeutic application of ultrasound with ultrasound contrast for patients with ST elevation myocardial infarction (STEMI). Recent trials demonstrated that sonothrombolysis, delivered before and after primary percutaneous coronary intervention (pPCI), increases infarct vessel patency, improves microvascular flow, reduces infarct size, and improves ejection fraction. However, it is unclear whether pre-pPCI sonothrombolysis is essential for therapeutic benefit. We designed a parallel 3-arm sham-controlled randomized controlled trial to address this. METHODS: Patients presenting with first STEMI undergoing pPCI within 6 hours of symptom onset were randomized 1:1:1 into 3 arms: sonothrombolysis pre-/post-pPCI (group 1), sham pre- sonothrombolysis post-pPCI (group 2), and sham pre-/post-pPCI (group 3). Our primary end point was infarct size (percentage of left ventricular mass) assessed by cardiac magnetic resonance imaging at day 4 ± 2. Secondary end points included myocardial salvage index (MSI) and echocardiographic parameters at day 4 ± 2 and 6 months. RESULTS: Our trial was ceased early due to the COVID pandemic. From 122 patients screened between September 2020 and June 2021, 51 patients (age 60, male 82%) were included postrandomization. Median sonothrombolysis took 5 minutes pre-pPCI and 15 minutes post-, without significant door-to-balloon delay. There was a trend toward reduction in median infarct size between group 1 (8% [interquartile range, 4,11]), group 2 (11% [7, 19]), or group 3 (15% [9, 22]). Similarly there was a trend toward improved MSI in group 1 (79% [64, 85]) compared to groups 2 (51% [45, 70]) and 3 (48% [37, 73]) No major adverse cardiac events occurred during hospitalization. CONCLUSIONS: Pre-pPCI sonothrombolysis may be key to improving MSI in STEMI. Multicenter trials and health economic analyses are required before clinical translation.

Cardiac magnetic relaxometry versus ejection fraction in anthracycline-related cardiac changes: a systematic review and meta-analysis.

PURPOSE: The purpose of this meta-analysis is to compare the magnitude of the changes in left ventricular ejection fraction (LVEF) and cardiac magnetic resonance (CMR) relaxometry techniques soon after the completion of anthracycline therapy. Anthracyclines are associated with myocardial functional and morphological changes. LVEF is currently used to identify the functional changes. Anthracyclines can also cause myocardial inflammation and oedema. This can be assessed using CMR relaxometry techniques; T1 and T2 mapping and extracellular volume (ECV) fraction. METHODS: Three databases were systematically searched for studies evaluating CMR relaxometry parameter at baseline and 1±1 months after anthracycline completion (the last search date 17 March 2023). CMR parameters pre and post anthracycline-based chemotherapy were abstracted. A random effects model was used to pool mean difference (MD) in LVEF and ECV. Standardised mean difference (SMD) was also calculated for T1 and T2 mapping due to the variations in techniques, normal ranges and for the comparison among the parameters. RESULTS: A total of 296 patients were included from 10 studies. 84% were female with a mean age of 54.9 years. Statistically significant alterations were observed in LVEF (MD -3.38% (95% CI -5.13%, -1.62%)) and ECV (1.92% (1.30%, 2.53%)). The pooled SMDs were also significant in LVEF, T1, T2 and ECV with -0.61 (-0.91, -0.30), 0.53 (0.16, 0.90), 0.59 (0.22, 0.96) and 0.74 (0.41, 1.06), respectively. CONCLUSIONS: Our meta-analysis demonstrated small but significant alterations in CMR relaxometry parameters soon after anthracycline therapy, where ECV was superior to LVEF and T1 or T2 mapping. However, these short-term MDs were below the minimal detectable differences. PROSPERO REGISTRATION NUMBER: CRD42020196296.

Non-line-of-sight snapshots and background mapping with an active corner camera.

The ability to form reconstructions beyond line-of-sight view could be transformative in a variety of fields, including search and rescue, autonomous vehicle navigation, and reconnaissance. Most existing active non-line-of-sight (NLOS) imaging methods use data collection steps in which a pulsed laser is directed at several points on a relay surface, one at a time. The prevailing approaches include raster scanning of a rectangular grid on a vertical wall opposite the volume of interest to generate a collection of confocal measurements. These and a recent method that uses a horizontal relay surface are inherently limited by the need for laser scanning. Methods that avoid laser scanning to operate in a snapshot mode are limited to treating the hidden scene of interest as one or two point targets. In this work, based on more complete optical response modeling yet still without multiple illumination positions, we demonstrate accurate reconstructions of foreground objects while also introducing the capability of mapping the stationary scenery behind moving objects. The ability to count, localize, and characterize the sizes of hidden objects, combined with mapping of the stationary hidden scene, could greatly improve indoor situational awareness in a variety of applications.

A Robust Purity Method for Biotherapeutics Using New Peak Detection in an LC-MS-Based Multi-Attribute Method.

New peak detection (NPD), as part of the LC-MS-based multi-attribute method (MAM), allows for sensitive and unbiased detection of new or changing site-specific attributes between a sample and reference that is not possible with conventional UV or fluorescence detection-based methods. MAM with NPD can serve as a purity test that can establish whether a sample and the reference are similar. The broad implementation of NPD in the biopharmaceutical industry has been limited by the potential presence of false positives or artifacts, which increase the analysis time and can trigger unnecessary investigations of product quality. Our novel contributions to the success of NPD are the curation of false positives, use of the known peak list concept, pairwise analysis approach, and the development of a NPD system suitability control strategy. In this report, we also introduce a unique experimental design utilizing sequence variant co-mixes to measure NPD performance. We show that NPD has superior performance relative to conventional control system methods in the detection of an unexpected change as compared with the reference. NPD is a new frontier in purity testing that reduces subjectivity, need for analyst intervention, and potential for missing unexpected product quality changes.

Role of Cardiac Magnetic Resonance Imaging and Troponin T in Definitive Diagnosis of Myocardial Infarction With Nonobstructive Coronary Arteries (MINOCA).

BACKGROUND: It is unknown whether the degree of high-sensitivity troponin T (hsTropT) elevation in patients with suspected myocardial infarction without obstructive coronary arteries (MINOCA) presentations can help predict the likelihood of an abnormal cardiac magnetic resonance (CMR) scan. In this study we describe the diagnostic utility of CMR in patients with MINOCA and assesses the effect of peak hsTropT levels at presentation on CMR diagnostic yield. METHODS: Records of consecutive patients (n = 1407) referred for CMR at a tertiary referral hospital between January 2016 and September 2021 were reviewed. A total of 70 patients met the criteria of MINOCA including ischemic chest pain, elevated peak hsTropT, and nonobstructive coronary artery disease (< 50% stenosis). The peak hsTropT levels within 72 hours of admission were identified. CMR images were generated using a 3.0 T Siemens scanner. Predictors of having an abnormal CMR were evaluated. RESULTS: CMR established a diagnosis in 71% (n = 50) of patients, with the most common CMR diagnosis being myopericarditis (n = 27; 39%). Time to CMR was an independent predictor of a normal CMR scan (odds ratio, 0.98; 95% confidence interval, 0.97-0.999). Peak hsTropT had a high diagnostic accuracy for identifying patients with an abnormal CMR scan (area under the receiver operator characteristic curve, 0.81; P < 0.001). The optimal hsTropT cutoff was 166 ng/L, with 72% sensitivity and specificity. A troponin value ≥ 166 ng/L was independently predictive of an abnormal CMR scan (odds ratio, 4.76; 95% confidence interval, 1.32-17.11). CONCLUSIONS: HsTropT and early CMR imaging are independently predictive of an abnormal CMR scan in patients with MINOCA. Additionally, the use of a hsTropT cutoff provides incremental predictive value to clinical parameters and time to CMR scanning in determining an abnormal scan.