Simplification of a registry-based algorithm for ejection fraction prediction in heart failure patients: Applicability in cardiology centres of the Netherlands.

Background: Left ventricular ejection fraction (EF) is used to categorize heart failure (HF) into phenotypes but this information is often missing in electronic health records or non-HF registries.

Methods: We tested the applicability of a simplified version of a multivariable algorithm, that was developed on data of the Swedish Heart Failure Registry to predict EF in patients with HF. We used data from 4,868 patients with HF from the Cardiology Centers of the Netherlands database, an organization of 13 cardiac outpatient clinics that operate between the general practitioner and the hospital cardiologist.

Combined strategy of upfront CTCA and optimal treatment for stable chest pain: rationale and design of the CLEAR-CAD trial.

Background: Patients with stable chest pain suspected of coronary artery disease (CAD) usually undergo multiple diagnostic tests to confirm or rule out obstructive CAD. Some tests may not effectively assess the presence of CAD, precluding optimal treatment. A diagnostic strategy of upfront computed tomography coronary angiography (CTCA) combined with optimal medical therapy (OMT) tailored to the extent of CAD may be superior to standard care in preventing major adverse cardiac events.

Microfluidic capillary electrophoresis - mass spectrometry for rapid charge-variant and glycoform assessment of monoclonal antibody biosimilar candidates.

Early-stage cell line screening is a vital step in developing biosimilars of therapeutic monoclonal antibodies (mAbs). While the quality of the manufactured antibodies is commonly assessed by charge-based separation methods employing UV absorbance detection, these methods lack the ability to identify resolved mAb variants. We evaluated the performance of microfluidic capillary electrophoresis coupled to mass spectrometry (MCE-MS) as a rapid tool for profiling mAb biosimilar candidates from clonal cell lines.

Can eHealth programs for cardiac arrhythmias be scaled-up by using the KardiaMobile algorithm?

Background: Remote monitoring devices for atrial fibrillation are known to positively contribute to the diagnostic process and therapy compliance. However, automatic algorithms within devices show varying sensitivity and specificity, so manual double-checking of electrocardiographic (ECG) recordings remains necessary.

Objective: The purpose of this study was to investigate the validity of the KardiaMobile algorithm within the Dutch telemonitoring program (HartWacht).

Investigating direct current potentials that affect native protein conformation during trapped ion mobility spectrometry-mass spectrometry.

Trapped ion mobility spectrometry-time-of-flight mass spectrometry (TIMS-TOFMS) has emerged as a tool to study protein conformational states. In TIMS, gas-phase ions are guided across the IM stages by applying direct current (DC) potentials (D1-6), which, however, might induce changes in protein structures through collisional activation. To define conditions for native protein analysis, we evaluated the influence of these DC potentials using the metalloenzyme bovine carbonic anhydrase (BCA) as primary test compound.

Fingerprinting of hydroxy propyl methyl cellulose by comprehensive two-dimensional liquid chromatography-mass spectrometry of monomers resulting from acid hydrolysis.

Hydroxypropyl methyl cellulose (HPMC) is a type of cellulose derivative with properties that render it useful in e.g. food, cosmetics, and pharmaceutical industry.

Online multimethod platform for comprehensive characterization of monoclonal antibodies in cell culture fluid from a single sample injection - Intact protein workflow.

Background: Therapeutic monoclonal antibodies (mAbs) comprise a large structural variability with respect to charge, size and post-translational modifications. These critical quality attributes (CQAs) need to be assessed during and after the production of mAbs. This normally requires off-line purification and sample preparation as well as several chromatographic selectivities, which makes the whole process time-consuming and error-prone.

Characterization of Dye-Loaded Poly(lactic--glycolic acid) Nanoparticles by Comprehensive Two-Dimensional Liquid Chromatography Combining Hydrodynamic and Reversed-Phase Liquid Chromatography.

Analytical methods for the assessment of drug-delivery systems (DDSs) are commonly suitable for characterizing individual DDS properties, but do not allow determination of several properties simultaneously. A comprehensive online two-dimensional liquid chromatography (LC × LC) system was developed that is aimed to be capable of characterizing both nanoparticle size and encapsulated cargo over the particle size distribution of a DDS by using one integrated method. Polymeric nanoparticles (NPs) with encapsulated hydrophobic dyes were used as model DDSs.

'The goddess that we serve': projecting international community at the first serial chemistry conferences, 1893-1914.

The emergence of conferences in the late nineteenth century significantly changed the ways in which the international scientific community functioned and experienced itself. In the early modern Republic of Letters, savants mainly related through print and correspondence, and apart from at local and later national levels, scholars rarely met. International conferences, by contrast, brought scientists together regularly, in the flesh and in great numbers.

The art of gathering: histories of international scientific conferences.

Hundreds of thousands of conferences have taken place since their first appearance in the late eighteenth century, yet the history of science has often treated them as stages for scientific practice, not as the play itself. Drawing on recent work in the history of science and of international relations, the introduction to this special issue suggests avenues for exploring the phenomenon of the international scientific conference, broadly construed, by highlighting the connected dimensions of communication, sociability and international relations. It lays out a typology of scientific conferences as a way of gaining an overview of their diversity in the nineteenth and twentieth centuries.

Capacitively coupled contactless conductivity detection to account for system-induced gradient deformation in liquid chromatography.

The time required for method development in gradient-elution liquid chromatography (LC) may be reduced by using an empirical modelling approach to describe and predict analyte retention and peak width. However, prediction accuracy is impaired by system-induced gradient deformation, which can be especially prominent for steep gradients. As the deformation is unique to each LC instrument, it needs to be corrected for if retention modelling for optimization and method transfer is to become generally applicable.

Micro-flow size-exclusion chromatography for enhanced native mass spectrometry of proteins and protein complexes.

Size-exclusion chromatography (SEC) employing aqueous mobile phases with volatile salts at neutral pH combined with native mass spectrometry (nMS) is a valuable tool to characterize proteins and protein aggregates in their native state. However, the liquid-phase conditions (high salt concentrations) frequently used in SEC-nMS hinder the analysis of labile protein complexes in the gas phase, necessitating higher desolvation-gas flow and source temperature, leading to protein fragmentation/dissociation. To overcome this issue, we investigated narrow SEC columns (1.

Trapped ion mobility mass spectrometry of new psychoactive substances: Isomer-specific identification of ring-substituted cathinones.

New psychoactive substances (NPS) are synthetic derivatives of illicit drugs designed to mimic their psychoactive effects. NPS are typically not controlled under drug acts or their legal status depends on their molecular structure. Discriminating isomeric forms of NPS is therefore crucial for forensic laboratories.

Characterizing Non-covalent Protein Complexes Using Asymmetrical Flow Field-Flow Fractionation On-Line Coupled to Native Mass Spectrometry.

We report an online analytical platform based on the coupling of asymmetrical flow field-flow fractionation (AF4) and native mass spectrometry (nMS) in parallel with UV-absorbance, multi-angle light scattering (MALS), and differential-refractive-index (UV-MALS-dRI) detectors to elucidate labile higher-order structures (HOS) of protein biotherapeutics. The technical aspects of coupling AF4 with nMS and the UV-MALS-dRI multi-detection system are discussed. The "slot-outlet" technique was used to reduce sample dilution and split the AF4 effluent between the MS and UV-MALS-dRI detectors.

High-Throughput Venomics.

In this study, we present high-throughput (HT) venomics, a novel analytical strategy capable of performing a full proteomic analysis of a snake venom within 3 days. This methodology comprises a combination of RP-HPLC-nanofractionation analytics, mass spectrometry analysis, automated in-solution tryptic digestion, and high-throughput proteomics. In-house written scripts were developed to process all the obtained proteomics data by first compiling all Mascot search results for a single venom into a single Excel sheet.

Principles and potential of solvent gradient size-exclusion chromatography for polymer analysis.

The properties of a polymeric material are influenced by its underlying molecular distributions, including the molecular-weight (MWD), chemical-composition (CCD), and/or block-length (BLD) distributions. Gradient-elution liquid chromatography (LC) is commonly used to determine the CCD. Due to the limited solubility of polymers, samples are often dissolved in strong solvents.

Composition mapping of highly substituted cellulose-ether monomers by liquid chromatography-mass spectrometry and probability-based data deconvolution.

Cellulose ethers (CEs) are semi-synthetic polymers produced by derivatization of natural cellulose, yielding highly substituted products such as ethyl hydroxyethyl cellulose (EHEC) or methyl ethyl hydroxyethyl cellulose (MEHEC). CEs are commonly applied as pharmaceutical excipients and thickening agents in paints and drymix mortars. CE properties, such as high viscosity in solution, solubility, and bio-stability are of high interest to achieve required product qualities, which may be strongly affected by the substitution pattern obtained after derivatization.

Coronary calcification measures predict mortality in symptomatic women and men.

Objective: To assess the prognostic value of absolute and sex-specific, age-specific and race/ethnicity-specific (Multi-Ethnic Study of Atherosclerosis, MESA) percentiles of coronary artery calcification in symptomatic women and men.

Methods: The study population consisted of 4985 symptomatic patients (2793 women, 56%) visiting a diagnostic outpatient cardiology clinic between 2009 and 2018 who were referred for cardiac CT to determine Coronary Artery Calcium Score (CACS). Regular care data were used and these data were linked to the databases of Statistics Netherlands for all-cause mortality data.

A Combined Bioassay and Nanofractionation Approach to Investigate the Anticoagulant Toxins of Mamba and Cobra Venoms and Their Inhibition by Varespladib.

Envenomation by elapid snakes primarily results in neurotoxic symptoms and, consequently, are the primary focus of therapeutic research concerning such venoms. However, mounting evidence suggests these venoms can additionally cause coagulopathic symptoms, as demonstrated by some Asian elapids and African spitting cobras. This study sought to investigate the coagulopathic potential of venoms from medically important elapids of the genera (true cobras), (rinkhals), and (mambas).

Chemometric Strategies for Fully Automated Interpretive Method Development in Liquid Chromatography.

The majority of liquid chromatography (LC) methods are still developed in a conventional manner, that is, by analysts who rely on their knowledge and experience to make method development decisions. In this work, a novel, open-source algorithm was developed for automated and interpretive method development of LC(-mass spectrometry) separations ("AutoLC"). A closed-loop workflow was constructed that interacted directly with the LC system and ran unsupervised in an automated fashion.

Accuracy of mobile 6-lead electrocardiogram device for assessment of QT interval: a prospective validation study.

Introduction: Ambulatory assessment of the heart rate-corrected QT interval (QTc) can be of diagnostic value, for example in patients on QTc-prolonging medication. Repeating sequential 12-lead electrocardiograms (ECGs) to monitor the QTc is cumbersome, but mobile ECG (mECG) devices can potentially solve this problem. As the accuracy of single-lead mECG devices is reportedly variable, a multilead mECG device may be more accurate.

Recycling gradient-elution liquid chromatography for the analysis of chemical-composition distributions of polymers.

Synthetic polymers typically show dispersity in molecular weight and potentially in chemical composition. For the analysis of the chemical-composition distribution (CCD) gradient liquid chromatography may be used. The CCD obtained using this method is often convoluted with an underlying molecular-weight distribution (MWD).