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Type 1 diabetes (T1D) is a prototypic T cell-mediated autoimmune disease. Because the islets of Langerhans are insulated from blood vessels by a double basement membrane and lack detectable lymphatic drainage, interactions between endocrine and circulating T cells are not permitted. Thus, we hypothesized that initiation and progression of anti-islet immunity required islet neolymphangiogenesis to allow T cell access to the islet. Combining microscopy and single cell approaches, the timing of this phenomenon in mice was situated between 5 and 8 wk of age when activated anti-insulin CD4 T cells became detectable in peripheral blood while peri-islet pathology developed. This "peri-insulitis," dominated by CD4 T cells, respected the islet basement membrane and was limited on the outside by lymphatic endothelial cells that gave it the attributes of a tertiary lymphoid structure. As in most tissues, lymphangiogenesis seemed to be secondary to local segmental endothelial inflammation at the collecting postcapillary venule. In addition to classic markers of inflammation such as CD29, V-CAM, and NOS, MHC class II molecules were expressed by nonhematopoietic cells in the same location both in mouse and human islets. This CD45- MHC class II+ cell population was capable of spontaneously presenting islet Ags to CD4 T cells. Altogether, these observations favor an alternative model for the initiation of T1D, outside of the islet, in which a vascular-associated cell appears to be an important MHC class II-expressing and -presenting cell.
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Diabetes Mellitus Tipo 1 , Ilhotas Pancreáticas , Humanos , Camundongos , Animais , Células Endoteliais , Antígenos de Histocompatibilidade Classe II , Inflamação/patologia , Camundongos Endogâmicos NODRESUMO
Abandonment of diversity, equity and inclusion programs undermines fairness and the productivity of research.
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The thermal distillation of crude oil mixtures is an energy-intensive process, accounting for nearly 1% of global energy consumption. Membrane-based separations are an appealing alternative or tandem process to distillation due to intrinsic energy efficiency advantages. We developed a family of spirocyclic polytriazoles from structurally diverse monomers for membrane applications. The resulting polymers were prepared by a convenient step-growth method using copper-catalysed azide-alkyne cycloaddition, providing very fast reaction rates, high molecular weights and solubilities in common organic solvents and non-interconnected microporosity. Fractionation of whole Arabian light crude oil and atmospheric tower bottom feeds using these materials enriched the low-boiling-point components and removed trace heteroatom and metal impurities (comparable performance with the lighter feed as the commercial polyimide, Matrimid), demonstrating opportunities to reduce the energy cost of crude oil distillation with tandem membrane processes. Membrane-based molecular separation under these demanding conditions is made possible by high thermal stability and a moderate level of dynamic chain mobility, leading to transient interconnections between micropores, as revealed by the calculations of static and swollen pore structures.
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Messenger RNA has now been used to vaccinate millions of people. However, the diversity of pulmonary pathologies, including infections, genetic disorders, asthma and others, reveals the lung as an important organ to directly target for future RNA therapeutics and preventatives. Here we report the screening of 166 polymeric nanoparticle formulations for functional delivery to the lungs, obtained from a combinatorial synthesis approach combined with a low-dead-volume nose-only inhalation system for mice. We identify P76, a poly-ß-amino-thio-ester polymer, that exhibits increased expression over formulations lacking the thiol component, delivery to different animal species with varying RNA cargos and low toxicity. P76 allows for dose sparing when delivering an mRNA-expressed Cas13a-mediated treatment in a SARS-CoV-2 challenge model, resulting in similar efficacy to a 20-fold higher dose of a neutralizing antibody. Overall, the combinatorial synthesis approach allowed for the discovery of promising polymeric formulations for future RNA pharmaceutical development for the lungs.
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COVID-19 , Animais , Camundongos , RNA Mensageiro/genética , SARS-CoV-2/genética , Polímeros/metabolismo , Pulmão , RNA/metabolismoRESUMO
Polymers of intrinsic microporosity (PIMs) have been used as precursors for the fabrication of porous carbon molecular sieve (CMS) membranes. PIM-1, a prototypical PIM material, uses a fused-ring structure to increase chain rigidity between spirobisindane repeat units. These two factors inhibit effective chain packing, thus resulting in high free volume within the membrane. However, a decrease of pore size and porosity was observed after pyrolytic conversion of PIM-1 to CMS membranes, attributed to the destruction of the spirocenter, which results in the "flattening" of the polymer backbone and graphite-like stacking of carbonaceous strands. Here, a spirobifluorene-based polymer of intrinsic microporosity (PIM-SBF) was synthesized and used to fabricate CMS membranes that showed significant increases in p-xylene permeability (approximately four times), with little loss in p-xylene/o-xylene selectivity (13.4 versus 14.7) for equimolar xylene vapor separations when compared to PIM-1-derived CMS membranes. This work suggests that it is feasible to fabricate such highly microporous CMS membranes with performances that exceed current state-of-the-art zeolites at high xylene loadings.
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PURPOSE OF REVIEW: This review navigates the landscape of precision anaesthesia, emphasising tailored and individualized approaches to anaesthetic administration. The aim is to elucidate precision medicine principles, applications, and potential advancements in anaesthesia. The review focuses on the current state, challenges, and transformative opportunities in precision anaesthesia. RECENT FINDINGS: The review explores evidence supporting precision anaesthesia, drawing insights from neuroscientific fields. It probes the correlation between high-dose intraoperative opioids and increased postoperative consumption, highlighting how precision anaesthesia, especially through initiatives like Safe Brain Initiative (SBI), could address these issues. The SBI represents multidisciplinary collaboration in perioperative care. SBI fosters effective communication among surgical teams, anaesthesiologists, and other medical professionals. SUMMARY: Precision anaesthesia tailors care to individual patients, incorporating genomic insights, personalised drug regimens, and advanced monitoring techniques. From EEG to cerebral/somatic oximetry, these methods enhance precision. Standardised reporting, patient-reported outcomes, and continuous quality improvement, alongside initiatives like SBI, contribute to improved patient outcomes. Precision anaesthesia, underpinned by collaborative programs, emerges as a promising avenue for enhancing perioperative care.
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Anestesia , Anestésicos , Humanos , Anestesia/métodos , Encéfalo , Assistência Centrada no Paciente , Assistência PerioperatóriaRESUMO
PURPOSE OF REVIEW: This review explores the intricacies of ethical anesthesia, exploring the necessity for precision anesthesia and its impact on patient-reported outcomes. The primary objective is to advocate for a defined aim, promoting the implementation of rules and feedback systems. The ultimate goal is to enhance precision anesthesia care, ensuring patient safety through the implementation of a teamwork and the integration of feedback mechanisms. RECENT FINDINGS: Recent strategies in the field of anesthesia have evolved from intraoperative monitorization to a wider perioperative patient-centered precision care. Nonetheless, implementing this approach encounters significant obstacles. The article explores the evidence supporting the need for a defined aim and applicable rules for precision anesthesia's effectiveness. The implementation of the safety culture is underlined. The review delves into the teamwork description with structured feedback systems. SUMMARY: Anesthesia is a multifaceted discipline that involves various stakeholders. The primary focus is delivering personalized precision care. This review underscores the importance of establishing clear aims, defined rules, and fostering effective and well tolerated teamwork with accurate feedback for improving patient-reported outcomes. The Safe Brain Initiative approach, emphasizing algorithmic monitoring and systematic follow-up, is crucial in implementing a fundamental and standardized reporting approach within patient-centered anesthesia care practice.
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Anestesia , Assistência Centrada no Paciente , Humanos , Anestesia/métodos , Anestesia/normas , Anestesia/ética , Anestesia/efeitos adversos , Assistência Centrada no Paciente/ética , Assistência Centrada no Paciente/normas , Anestesiologia/ética , Anestesiologia/normas , Segurança do Paciente/normas , Medicina de Precisão/métodos , Medicina de Precisão/ética , Medicina de Precisão/normas , Equipe de Assistência ao Paciente/ética , Equipe de Assistência ao Paciente/normas , Equipe de Assistência ao Paciente/organização & administração , Medidas de Resultados Relatados pelo Paciente , Monitorização Intraoperatória/métodos , Monitorização Intraoperatória/normasRESUMO
Azobenzenes (ABs) are versatile compounds featured in numerous applications for energy storage systems, such as solar thermal storages or phase change materials. Additionally, the reversible one-electron reduction of these diazenes to the nitrogen-based radical anion has been used in battery applications. Although the oxidation of ABs is normally irreversible, 4,4'-diamino substitution allows a reversible 2e- oxidation, which is attributed to the formation of a stable bis-quinoidal structure. Herein, we present a system that shows a bipolar redox behaviour. In this way, ABs can serve not only as anolytes, but also as catholytes. The resulting redox potentials can be tailored by suitable amine- and ring-substitution. For the first time, the solid-state structure of the oxidized form could be characterized by X-ray diffraction.
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The asialoglycoprotein receptor (ASGPR) is expressed in high density on hepatocytes. Multivalent variants of galactosyl carbohydrates bind ASGPR with high affinity, enabling hepatic delivery of ligand-bound cargo. Virus-like particle (VLP) conjugates of a relatively high-affinity ligand were efficiently endocytosed by ASGPR-expressing cells in a manner strongly dependent on the nature and density of ligand display, with the best formulation using a nanomolar-, but not a picomolar-level, binder. Optimized particles were taken up by HepG2 cells with greater efficiency than competing small molecules or the natural multigalactosylated ligand, asialoorosomucoid. Upon systemic injection in mice, these VLPs were rapidly cleared to the liver and were found in association with sinusoidal endothelial cells, Kupffer cells, hepatocytes, dendritic cells, and other immune cells. Both ASGPR-targeted and nontargeted particles were distributed similarly to endothelial and Kupffer cells, but targeted particles were distributed to a greater number and fraction of hepatocytes. Thus, selective cellular trafficking in the liver is difficult to achieve: even with the most potent ASGPR targeting available, barrier cells take up much of the injected particles and hepatocytes are accessed only approximately twice as efficiently in the best case.
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Células Endoteliais , Fígado , Animais , Camundongos , Receptor de Asialoglicoproteína , Ligantes , Células Endoteliais/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismoRESUMO
The therapeutic value of delivering recombinant uricase to human patients has been appreciated for decades. The development of therapeutic uricases has been hampered by the fact that humans do not encode an endogenous uricase and therefore most recombinant forms of the protein are recognized as foreign by the immune system and are therefore highly immunogenic. In order to both shield and stabilize the active enzyme, we encapsulated a functional ancestral uricase in recombinant, noninfectious Qß capsid nanoparticles and characterized its catalytic activity. Oral delivery of the nanoparticles moderated key symptoms of kidney dysfunction in uricase-knockout mice by lowering uric acid levels. Histological kidney samples of the treated mice suggest that delivery of recombinant uricase had a protective effect against the destructive effects of uric acid that lead to renal failure caused by hyperuricemia.
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Hiperuricemia , Nanopartículas , Humanos , Camundongos , Animais , Hiperuricemia/tratamento farmacológico , Hiperuricemia/genética , Ácido Úrico , Urato Oxidase/genética , Camundongos KnockoutRESUMO
Oligonucleotides are powerful molecules for programming function and assembly. When arrayed on nanoparticle scaffolds in high density, the resulting molecules, spherical nucleic acids (SNAs), become imbued with unique properties. We used the copper-catalyzed azide-alkyne cycloaddition to graft oligonucleotides on Qß virus-like particles to see if such structures also gain SNA-like behavior. Copper-binding ligands were shown to promote the click reaction without degrading oligonucleotide substrates. Reactions were first optimized with a small-molecule fluorogenic reporter and were then applied to the more challenging synthesis of polyvalent protein nanoparticle-oligonucleotide conjugates. The resulting particles exhibited the enhanced cellular uptake and protection from nuclease-mediated oligonucleotide cleavage characteristic of SNAs, had similar residence time in the liver relative to unmodified particles, and were somewhat shielded from immune recognition, resulting in nearly 10-fold lower antibody titers relative to unmodified particles. Oligonucleotide-functionalized virus-like particles thus provide an interesting option for protein nanoparticle-mediated delivery of functional molecules.
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Nanopartículas , Ácidos Nucleicos , Oligonucleotídeos/química , Cobre/química , Proteínas , Azidas/química , Alcinos/química , Química Click , Reação de CicloadiçãoRESUMO
Enzyme activity requires sequential binding and chemical transformation of substrates. While directed evolution and random mutagenesis are common methods for improving catalytic activity, these methods do not allow for independent control of KM and kcat. To achieve such control, we envisioned that the colocalization of aptamers and enzymes that act on the same molecule could increase catalytic efficiency through preconcentration of substrate. We explored this concept with cocaine esterase and anticocaine aptamers having varying KD values, both encapsulated in MS2 virus-like particles. Rate enhancements were observed with magnitudes dependent on both aptamer:enzyme stoichiometry and aptamer KD, peaking when aptamer KD and enzyme KM were roughly equivalent. This beneficial effect was lost when either aptamer binding was too tight or the aptamers were not constrained to be close to the catalyst. This work demonstrates a modular way to enhance catalysis by independently controlling substrate capture and release to the processing enzyme.
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Aptâmeros de Nucleotídeos , Catálise , Aptâmeros de Nucleotídeos/química , CinéticaRESUMO
We report the synthesis of 14 2,2'-disubstituted 9,9'-bifluorenylidenes as molecular balances for the quantification of London dispersion interactions between various dispersion energy donors. For all balances, we measured ΔGZ/E at 333 K using 1H NMR in seven organic solvents. For various alkyl and aryl substituents, we generally observe a preference for the "folded" Z-isomer due to attractive London dispersion interactions. The cyclohexyl-substituted system shows the largest Z-preference in this study with ΔGZ/E = -0.6 ± 0.05 kcal mol-1 in all solvents, owing to the rotational freedom of cyclohexyl groups paired with their large polarizability that maximizes London dispersion interactions. On the other hand, rigid and sterically more demanding substituents like tert-butyl unexpectedly favor the unfolded E-isomer. This is a result of the close relative position in which the functional groups are positioned in this molecular balance. This close proximity is the reason for the increase of Pauli repulsion in the Z-isomers with large rigid substituents (tert-butyl, adamantyl, and diamantyl) which leads to an equilibrium shift toward the unfolded E-form. While we were able to reproduce most of our experimental trends qualitatively using contemporary computational chemistry methods, quantitative accuracy of the employed methods still needs further improvement.
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BACKGROUND: The risk of superinfections and associations with mortality among patients with corona virus disease 2019 (COVID-19) receiving veno-venous extracorporeal membrane oxygenation (VV-ECMO) is poorly elucidated. METHOD: We identified all patients with COVID-19 treated with VV-ECMO >24 h at Rigshospitalet, Denmark from March 2020 to December 2021. Data were obtained by review of medical files. Associations between superinfections and mortality were assessed by logistic regression analyses adjusted for sex and age. RESULTS: Fifty patients, median age 53 years (interquartile range [IQR] 45-59), 66% male, were included. Median time on VV-ECMO was 14.5 days (IQR 6.3-23.5), 42% were discharged from hospital alive. Bacteremia, ventilator associated pneumonia (VAP), invasive candidiasis, pulmonary aspergillosis, herpes simplex virus, and cytomegalovirus (CMV) were detected in 38%, 42%, 12%, 12%, 14%, and 20% of patients, respectively. No patients with pulmonary aspergillosis survived. CMV was associated with increased risk of death, odds ratio 12.6 (95% confidence interval 1.9-257, p = .05), whereas we found no associations between other superinfections and risk of death. CONCLUSION: Bacteremia and VAP are common but does not seem to affect mortality, whereas pulmonary aspergillosis and CMV are associated with poor prognosis among COVID-19 patients treated with VV-ECMO.
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COVID-19 , Infecções por Citomegalovirus , Oxigenação por Membrana Extracorpórea , Aspergilose Pulmonar , Superinfecção , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , COVID-19/complicações , COVID-19/terapia , Oxigenação por Membrana Extracorpórea/efeitos adversos , Superinfecção/etiologia , Aspergilose Pulmonar/etiologia , Infecções por Citomegalovirus/etiologia , Estudos RetrospectivosRESUMO
Postoperative delirium (POD) is an adverse but often preventable complication of surgery and surgery-related anaesthesia, and increasingly prevalent. This article provides an overview on non-pharmacological preventive measures, divided into individualized and non-individualized measures. Non-individualized measures, such as the most minimally invasive surgical procedure, avoidance of unnecessary fasting before surgery, and the most tolerable anaesthesia are used to minimize the risk of POD in all patients. Based on the results of preoperative screenings for risk factors such as frailty or cognitive impairment, individualized measures may encompass prehabilitation, treatment of specific risk factors, operation room companionship or cognitive, motor, and sensory stimulation as well as social support. This article additionally lists several examples of best practice approaches already implemented in German-speaking countries and websites for further readings.
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Anestesia , Anestesiologia , Delírio do Despertar , Fragilidade , Humanos , Delírio do Despertar/prevenção & controle , JejumRESUMO
BACKGROUND: The Internet is commonly used by patients to acquire health information. To date, no studies have evaluated the quality of information available on YouTube regarding lymphangioleiomyomatosis (LAM). Our aim was to determine the quality and content of YouTube videos regarding LAM and to compare the information provided with current knowledge and guidelines about the disease. METHODS: The first 200 video hits on YouTube in English for the search term "lymphangioleiomyomatosis" were recorded. All videos suitable for patient education on LAM were included. Video quality was analyzed independently by two investigators utilizing the Health on the Net (HONcode) score, which assesses whether websites provide understandable, accessible, and trustworthy health information; the DISCERN score, which evaluates the quality of information about treatment decisions; and a newly developed LAM-related content score (LRCS) with 31 guideline elements. RESULTS: The search identified 64 eligible videos. The "engagement rate" of 0.3 was low, with a median number of views of 408 (range 42-73,943), a median of 4 likes (range 0-2082), and the majority (53%) receiving a low HONcode score (≤ 2) and only 10% of videos achieving a high score (> 5). The median DISCERN score was 28 (range 15-61, maximum possible score 80), indicating poor video quality and reliability. The median LRCS was 8 (range 0-29, maximum possible score 31) and videos frequently failed to provide sources of information. CONCLUSIONS: Online resources could contribute to the limited and often inaccurate information available to patients with LAM, with only a few YouTube videos providing high-quality patient-relevant information.
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Linfangioleiomiomatose , Mídias Sociais , Humanos , Disseminação de Informação , Linfangioleiomiomatose/diagnóstico , Linfangioleiomiomatose/terapia , Educação de Pacientes como Assunto , Reprodutibilidade dos Testes , Gravação em VídeoRESUMO
We evaluate the use of the cohesive energy density (ced) as a quantitative descriptor for solvophobic effects in organic solvents by measuring ΔGZ/E of the rigid Z- and E-2,2'-diethynyl-9,9'-bifluorenylidene. In line with previously employed balances, solvent-dependent changes in ΔGZ/E are predominantly induced by solvophobic effects, leading to a strong correlation with the solvent's ced. We re-emphasize the role of ceds as quantitative descriptors of solvophobic effects of organic solvents. Our experimental findings are well supported by B3LYP-D3/def2TZVP computations.
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Hidrocarbonetos , SolventesRESUMO
Virus-like particles (VLPs) derived from Leviviridae virions contain substantial amounts of cellular and plasmid-derived RNA. This encapsidated polynucleotide serves as a reservoir for the efficient binding of the intercalating dye thiazole orange (TO). Polyethylene glycol (PEG) molecules and oligopeptides of varying length, end-functionalized with TO, were loaded into VLPs up to approximately 50 % of the mass of the capsid protein (hundreds to thousands of cargo molecules per particle, depending on size). The kinetics of TO-PEG binding included a significant entropic cost for the reptation of long chains through the capsid pores. Cargo molecules were released over periods of 20-120â hours following simple reversible first-order kinetics in most cases. These observations define a simple general method for the noncovalent packaging, and subsequent release, of functional molecules inside nucleoprotein nanocages in a manner independent of modifications to the capsid protein.
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CapsídeoRESUMO
Virus-like particles (VLPs) constitute large, polyvalent platforms onto which a wide variety of functional units can be grafted. Their use in biological settings often depends on their specific binding to cells or receptors of interest; this can be compromised by excessive nonspecific association with other cells. We found that lysine residues mediate such nonspecific interactions, presumably by virtue of protonation and interaction with anionic membrane lipid headgroups and/or complementary residues of cell surface proteins and polysaccharides. Chemical acylation of surface-exposed amines of the Qß VLP led to a significant reduction in the association of particles with mammalian cells. Single-point mutations of particular lysine residues to either glutamine, glutamic acid, tryptophan, or phenylalanine were mostly well-tolerated and formed intact capsids, but the introduction of double and triple mutants was far less forgiving. Introduction of glutamic acid at position 13 (K13E) led to a dramatic increase in cellular binding, whereas removal of the lysine at position 46 (K46Q) led to an equally striking reduction. Several plasma membrane components were found to specifically interact with the Qß capsid irrespective of surface charge. These results suggest that specific cellular interactions are engaged or obviated by such mutations and provide us with more "benign" particles to which can be added binding functionality for targeted delivery applications.
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Allolevivirus , Mutação Puntual , Animais , Capsídeo , Proteínas do Capsídeo/genética , Membrana CelularRESUMO
The properties of enzymes packaged within the coat protein shell of virus-like particles (VLPs) were studied to provide a comprehensive assessment of such factors. Such entrainment did not seem to perturb enzyme function, but it did significantly enhance enzyme stability against several denaturing stimuli such as heat, organic solvents, and chaotropic agents. This improvement in performance was found to be general and independent of the number of independent subunits required and of the number of catalytically active enzymes packaged. Packaged enzymes were found by measurements of intrinsic tryptophan fluorescence to retain some of their native folded structure even longer than their catalytic activity, suggesting that protein folding is a significant component of the observed catalytic benefits. While we are unable to distinguish between kinetic and thermodynamic effects - including inhibition of enzyme unfolding, acceleration of refolding, and biasing of folding equilibria - VLP packaging appears to represent a useful general strategy for the stabilization of enzymes that operate on diffusible substrates and products.