Factors Associated with Shock at Presentation in Kawasaki Disease Versus Multisystem Inflammatory Syndrome in Children Associated with COVID-19.

Background: While clinical overlap between Kawasaki disease (KD) and multisystem inflammatory syndrome in children (MIS-C) has been evident, information regarding those presenting with shock has been limited. We sought to determine associations with shock within and between diagnosis groups.

Methods: The International KD Registry enrolled contemporaneous patients with either KD or MIS-C from 39 sites in 7 countries from 01/2020 to 01/2023.

Infectious etiology of intussusception in Indian children less than 2 years old: a matched case-control analysis.

Background: Enteric infections are hypothesized to be associated with intussusception in children. A small increase in intussusception following rotavirus vaccination has been seen in some settings. We conducted post-marketing surveillance for intussusception following rotavirus vaccine, Rotavac introduction in India and evaluated association of intussusception with enteric pathogens.

Modeling High Concentration Bisalt-in-Sulfolane Electrolytes and the Observation of Ligand-Bridged Cation-Pair Complexes.

Despite the abundance of sodium over lithium in Earth's crust and the copious amounts of expensive lithium salt required to make Li-ion high-concentration electrolytes (HCEs), studies of HCEs made from sodium salts remain sparse. A comparative molecular-level study of Li- and Na-ion HCEs and mixed cation or bisalt HCEs in an organic solvent is missing. To fill this gap, we studied model HCEs of pure and mixed Li and Na salts of bis(fluorosulfonyl)amide (FSI) in sulfolane using a confluence of classical molecular dynamics (MD), ab initio MD (AIMD) simulations, and quantum chemical cluster calculations.

HP35 Protein in the Mesopore of MIL-101(Cr) MOF: A Model to Study Cotranslocational Unfolding.

The immobilization of enzymes in metal-organic framework (MOF) cages is important in biotechnology. In this context, the mechanism of translocation of proteins through the cavities of the MOF and the roles played by confinement and MOF chemistry in giving rise to stable protein intermediates that are otherwise transiently populated in the physiological environment are important questions to be addressed. These unexplored aspects are examined with villin headpiece (HP35) as a model protein confined within a mesopore of MIL-101(Cr) using molecular dynamics simulations.

Sex-specific differences in systemic immune responses in MIS-C children.

Multisystem Inflammatory Syndrome in Children (MIS-C) is a rare manifestation of Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2) infection that can result in increased morbidity and mortality. Mounting evidence describes sex disparities in the clinical outcomes of coronavirus disease 2019 (COVID-19). However, there is a lack of information on sex-specific differences in immune responses in MIS-C.

Red Circularly Polarized Luminescence from Dimeric H-Aggregates of Acridine Orange by Chiral Induction.

Understanding the mechanism of chirality transfer from a chiral surface to an achiral molecule is essential for designing molecular systems with tunable chiroptical properties. These aspects are explored herein using l- and d-isomers of alkyl valine amphiphiles, which self-assemble in water as nanofibers possessing a negative surface charge. An achiral chromophore, acridine orange, upon electrostatic binding on these surfaces displays mirror-imaged bisignated circular dichroism and red-emitting circularly polarized luminescence signals with a high dissymmetry factor.

Liquid-Vapor Interface of Aqueous Ethylene Glycol Solutions: A Molecular Dynamics Study.

While the organic constituent in an aqueous binary solution enriches its liquid-vapor (l-v) interface, the extent of enrichment can depend nonlinearly on its mole fraction. A microscopic quantification and rationalization of this behavior are crucial to understand the dependence of properties such as surface tension and evaporation rate of the solution on its composition. Extensive all-atom molecular dynamics simulations of aqueous ethylene glycol (EG) solutions show that the composition of the solution at the l-v interface deviates the most from that in the bulk solution at an EG mole fraction of 0.

Lipase A from : Substrate Binding, Conformational Dynamics, and Signatures of a Lid.

Protein-ligand binding studies are crucial for understanding the molecular basis of biological processes and for further advancing industrial biocatalysis and drug discovery. Using computational modeling and molecular dynamics simulations, we investigated the binding of a butyrate ester substrate to the lipase A (LipA) enzyme of . Besides obtaining a close agreement of the binding free energy with the experimental value, the study reveals a remarkable reorganization of the catalytic triad upon substrate binding, leading to increased essential hydrogen bond populations.

Noncovalent interaction guided selectivity of haloaromatic isomers in a flexible porous coordination polymer.

Porous, supramolecular structures exhibit preferential encapsulation of guest molecules, primarily by means of differences in the order of (noncovalent) interactions. The encapsulation preferences can be for geometry (dimension and shape) and the chemical nature of the guest. While geometry-based sorting is relatively straightforward using advanced porous materials, designing a "chemical nature" specific host is not.

Understanding the Anomalous Diffusion of Water in Aqueous Electrolytes Using Machine Learned Potentials.

The diffusivity of water in aqueous cesium iodide solutions is larger than that in neat liquid water and vice versa for sodium chloride solutions. Such peculiar ion-specific behavior, called anomalous diffusion, is not reproduced in typical force field based molecular dynamics (MD) simulations due to inadequate treatment of ion-water interactions. Herein, this hurdle is tackled by using machine learned atomic potentials (MLPs) trained on data from density functional theory calculations.

Supramolecular Polymerization of a Pyrene-Substituted Diamide and Its Ensemble of Kinetically Trapped Configurations.

The prevalence of kinetically accessible states in supramolecular polymerization pathways has been exploited to control the growth of the polymer and thereby to obtain niche morphologies. Yet, these pathways themselves are not easily amenable for experimental delineation but could potentially be understood through molecular dynamics (MD) simulations. Herein, we report an extensive investigation of the self-assembly of pyrene-substituted diamide (PDA) monomers in solution, conducted using atomistic MD simulations and advanced sampling methods.

Structurally Induced Chirality of an Achiral Chromophore on Self-Assembled Nanofibers: A Twist Makes It Chiral.

The surface domains of self-assembled amphiphiles are well-organized and can perform many physical, chemical, and biological functions. Here, we present the significance of chiral surface domains of these self-assemblies in transferring chirality to achiral chromophores. These aspects are probed using l- and d-isomers of alkyl alanine amphiphiles which self-assemble in water as nanofibers, possessing a negative surface charge.

Levels of Complement Components in Children With Acute COVID-19 or Multisystem Inflammatory Syndrome.

Importance: Multisystem inflammatory syndrome in children (MIS-C) is a severe and unrestrained inflammatory response with multiorgan involvement, which occurs within a few weeks following the resolution of acute SARS-CoV-2 infection. The complement system is a vital part of the innate immune system and plays a role in COVID-19 pathogenesis.

Objective: To examine and compare the levels of complement components and regulators along with complement activation products in the different clinical spectrum of children with SARS-CoV-2 and a control group.

Endobronchial lesion in an adolescent with hemoptysis biopsy or not to biopsy?

An 11-year-old girl was brought with complaints of recurrent massive hemoptysis. A computerized tomography (CT) of the chest showed ground glass opacities on the right lower lobe, and a CT angiography showed hypertrophied right pulmonary artery. Flexible bronchoscopy revealed a sessile friable lesion in the right lower lobe, raising suspicion of either a tumor or a vascular malformation.

Revisiting the Burden Borne by Fumarase: Enzymatic Hydration of an Olefin.

Fumarate hydratase (FH) is a remarkable catalyst that decreases the free energy of the catalyzed reaction by 30 kcal mol, much larger than most exceptional enzymes with extraordinary catalytic rates. Two classes of FH are observed in nature: class-I and class-II, which have different folds, yet catalyze the same reversible hydration/dehydration reaction of the dicarboxylic acids fumarate/malate, with equal efficiencies. Using class-I FH from the hyperthermophilic archaeon (Mj) as a model along with comparative analysis with the only other available class-I FH structure from (Lm), we provide insights into the molecular mechanism of catalysis in this class of enzymes.

Role of matrix metalloproteinases in multi-system inflammatory syndrome and acute COVID-19 in children.

Introduction: Multisystem Inflammatory Syndrome in children (MIS-C) is a serious inflammatory sequela of SARS-CoV2 infection. The pathogenesis of MIS-C is vague and matrix metalloproteinases (MMPs) may have an important role. Matrix metalloproteinases (MMPs) are known drivers of lung pathology in many diseases.

Unique cellular immune signatures of multisystem inflammatory syndrome in children.

The clinical presentation of MIS-C overlaps with other infectious/non-infectious diseases such as acute COVID-19, Kawasaki disease, acute dengue, enteric fever, and systemic lupus erythematosus. We examined the ex-vivo cellular parameters with the aim of distinguishing MIS-C from other syndromes with overlapping clinical presentations. MIS-C children differed from children with non-MIS-C conditions by having increased numbers of naïve CD8+ T cells, naïve, immature and atypical memory B cells and diminished numbers of transitional memory, stem cell memory, central and effector memory CD4+ and CD8+ T cells, classical, activated memory B and plasma cells and monocyte (intermediate and non-classical) and dendritic cell (plasmacytoid and myeloid) subsets.

Molecular simulations explain the exceptional thermal stability, solvent tolerance and solubility of protein-polymer surfactant bioconjugates in ionic liquids.

Proteins complexed electrostatically with polymer surfactants constitute a viscous liquid by themselves, called the solvent-free protein liquid (SFPL). A solution of SFPL in a room temperature ionic liquid (PS-IL) offers the protein hyperthermal stability, higher solubility and greater IL tolerance. A generic understanding of these protein-polymer systems is obtained herein through extensive atomistic molecular dynamics simulations of three different enzymes (lipase A, lysozyme and myoglobin) under various conditions.

Conformer Selection Upon Dilution with Water: The Fascinating Case of Liquid Ethylene Glycol Studied via Molecular Dynamics Simulations.

The aqueous solution of ethylene glycol (EG) is a binary liquid mixture that displays rich conformational and structural behaviour, which has not yet been adequately explored through atomistic molecular dynamics simulations. Herein, employing an accurate force field for EG, several physical properties of this solution are calculated to be in quantitative agreement with experimental data. While 79 % of molecules in neat liquid EG exist with their central OCCO dihedral in the gauche state, this fraction increases to 89 % in the dilute aqueous solution, largely in response to the increase in the static dielectric constant of the solution from that of neat liquid EG.

Tailoring a robust Al-MOF for trapping CH and CH towards efficient CH purification from quaternary mixtures.

Light hydrocarbon separation is considered one of the most industrially challenging and desired chemical separation processes and is highly essential in polymer and chemical industries. Among them, separating ethylene (CH) from C2 hydrocarbon mixtures such as ethane (CH), acetylene (CH), and other natural gas elements (CO, CH) is of paramount importance and poses significant difficulty. We demonstrate such separations using an Al-MOF synthesised earlier as a non-porous material, but herein endowed with hierarchical porosity created under microwave conditions in an equimolar water/ethanol solution.

Gate Opening without Volume Change Triggers Cooperative Gas Interactions, Underpins an Isotherm Step in Metal-Organic Frameworks.

Three halogenated metal-organic frameworks (MOFs) reported recently exhibited a second step in their CO gas adsorption isotherms. The emergence of halogen-bonding interactions beyond a threshold gas pressure between the framework halogen and the CO guest was conjectured to be the underlying reason for the additional step in the isotherm. Our investigation employing periodic density functional theory calculations did not show significant interactions between the halogen and CO molecules.

Insights into substrate behavior in a solvent-free protein liquid to rationalize its reduced catalytic rate.

When proteins are engineered with a polymer surfactant coating on their surface, they can form a liquid phase by themselves, without the need for a solvent, such as, say, water. However, such solvent-free protein liquids (SFPL), despite their capability to function at temperatures above those in aqueous solutions, exhibit much reduced catalytic rates. A comprehensive understanding of the nature of substrates in such liquids is crucial to reason out the reduced catalytic activity of enzymes as SFPL media, and thus identify the means to improve the same.

Liquid ethylene glycol: prediction of physical properties, conformer population and interfacial enrichment with a refined non-polarizable force field.

Periodic density functional theory based molecular dynamics simulations confirm the fraction of molecules in neat liquid ethylene glycol with their central OCCO dihedral in the conformation to be 21% at ambient conditions, while the rest are conformers. Using this result as a benchmark, two non-polarizable force fields are developed herein to reproduce the conformer populations in the liquid, an important aspect inadequately addressed in several generic force fields. The mean dipole moment of a molecule in the liquid is estimated to be about 40% enhanced over its value in the gas phase, a feature discerned AIMD simulations and fairly reproduced by our force fields.

Ileal Perforation and Enteric Fever: Implications for Burden of Disease Estimation.

Background: Ileal perforation occurs in about 1% of enteric fevers as a complication, with a case fatality risk (CFR) of 20%-30% in the early 1990s that decreased to 15.4% in 2011 in South East Asia. We report nontraumatic ileal perforations and its associated CFR from a 2-year prospective enteric fever surveillance across India.