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1.
Nature ; 628(8007): 326-332, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38480891

RESUMEN

Heteroarenes are ubiquitous motifs in bioactive molecules, conferring favourable physical properties when compared to their arene counterparts1-3. In particular, semisaturated heteroarenes possess attractive solubility properties and a higher fraction of sp3 carbons, which can improve binding affinity and specificity. However, these desirable structures remain rare owing to limitations in current synthetic methods4-6. Indeed, semisaturated heterocycles are laboriously prepared by means of non-modular fit-for-purpose syntheses, which decrease throughput, limit chemical diversity and preclude their inclusion in many hit-to-lead campaigns7-10. Herein, we describe a more intuitive and modular couple-close approach to build semisaturated ring systems from dual radical precursors. This platform merges metallaphotoredox C(sp2)-C(sp3) cross-coupling with intramolecular Minisci-type radical cyclization to fuse abundant heteroaryl halides with simple bifunctional feedstocks, which serve as the diradical synthons, to rapidly assemble a variety of spirocyclic, bridged and substituted saturated ring types that would be extremely difficult to make by conventional methods. The broad availability of the requisite feedstock materials allows sampling of regions of underexplored chemical space. Reagent-controlled radical generation leads to a highly regioselective and stereospecific annulation that can be used for the late-stage functionalization of pharmaceutical scaffolds, replacing lengthy de novo syntheses.


Asunto(s)
Carbono , Técnicas de Química Sintética , Compuestos Heterocíclicos con 1 Anillo , Preparaciones Farmacéuticas , Carbono/química , Ciclización , Compuestos Heterocíclicos con 1 Anillo/síntesis química , Compuestos Heterocíclicos con 1 Anillo/química , Solubilidad , Oxidación-Reducción , Fotoquímica , Preparaciones Farmacéuticas/síntesis química , Preparaciones Farmacéuticas/química , Técnicas de Química Sintética/métodos
2.
Nature ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38843825

RESUMEN

The ability to tame high-energy intermediates is critical for synthetic chemistry, enabling the construction of complex molecules and propelling advances in the field of synthesis. Along these lines, carbenes and carbenoid intermediates are particularly attractive, but often elusive, high-energy intermediates.1,2 Classical methods to access metal carbene intermediates exploit two-electron chemistry to form the critical carbon-metal bond. However, these methods are often prohibitive due to reagent safety concerns, limiting their broad implementation in synthesis.3-6 Mechanistically, an alternative approach to carbene intermediates that could circumvent these pitfalls would involve two single-electron steps: radical addition to a metal to forge the initial carbon-metal bond followed by redox-promoted α-elimination to yield the desired metal carbene intermediate. Herein, this strategy is realized through a metallaphotoredox platform that exploits iron carbene reactivity using readily available chemical feedstocks as radical sources and α-elimination from six classes of previously underexploited leaving groups. These discoveries permit cyclopropanation and σ-bond insertion into N-H, S-H, and P-H bonds from abundant and bench-stable carboxylic acids, amino acids, and alcohols, thereby providing a general solution to the challenge of carbene-mediated chemical diversification.

3.
Immunity ; 50(2): 378-389.e5, 2019 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-30784579

RESUMEN

Currently, we lack an understanding of the individual and combinatorial roles for chemokine receptors in the inflammatory process. We report studies on mice with a compound deletion of Ccr1, Ccr2, Ccr3, and Ccr5, which together control monocytic and eosinophilic recruitment to resting and inflamed sites. Analysis of resting tissues from these mice, and mice deficient in each individual receptor, provides clear evidence for redundant use of these receptors in establishing tissue-resident monocytic cell populations. In contrast, analysis of cellular recruitment to inflamed sites provides evidence of specificity of receptor use for distinct leukocyte subtypes and no indication of comprehensive redundancy. We find no evidence of involvement of any of these receptors in the recruitment of neutrophils or lymphocytes to resting or acutely inflamed tissues. Our data shed important light on combinatorial inflammatory chemokine receptor function and highlight Ccr2 as the primary driver of myelomonocytic cell recruitment in acutely inflamed contexts.


Asunto(s)
Eosinófilos/inmunología , Inflamación/inmunología , Monocitos/inmunología , Receptores CCR/inmunología , Animales , Quimiocinas/inmunología , Quimiocinas/metabolismo , Eosinófilos/metabolismo , Perfilación de la Expresión Génica/métodos , Inflamación/genética , Inflamación/metabolismo , Linfocitos/inmunología , Linfocitos/metabolismo , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Monocitos/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Receptores CCR/genética , Receptores CCR/metabolismo , Receptores CCR1/inmunología , Receptores CCR1/metabolismo , Receptores CCR2/inmunología , Receptores CCR2/metabolismo , Receptores CCR3/inmunología , Receptores CCR3/metabolismo , Receptores CCR5/inmunología , Receptores CCR5/metabolismo
4.
Nature ; 577(7788): 89-94, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31894144

RESUMEN

Screening mammography aims to identify breast cancer at earlier stages of the disease, when treatment can be more successful1. Despite the existence of screening programmes worldwide, the interpretation of mammograms is affected by high rates of false positives and false negatives2. Here we present an artificial intelligence (AI) system that is capable of surpassing human experts in breast cancer prediction. To assess its performance in the clinical setting, we curated a large representative dataset from the UK and a large enriched dataset from the USA. We show an absolute reduction of 5.7% and 1.2% (USA and UK) in false positives and 9.4% and 2.7% in false negatives. We provide evidence of the ability of the system to generalize from the UK to the USA. In an independent study of six radiologists, the AI system outperformed all of the human readers: the area under the receiver operating characteristic curve (AUC-ROC) for the AI system was greater than the AUC-ROC for the average radiologist by an absolute margin of 11.5%. We ran a simulation in which the AI system participated in the double-reading process that is used in the UK, and found that the AI system maintained non-inferior performance and reduced the workload of the second reader by 88%. This robust assessment of the AI system paves the way for clinical trials to improve the accuracy and efficiency of breast cancer screening.


Asunto(s)
Inteligencia Artificial/normas , Neoplasias de la Mama/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Femenino , Humanos , Mamografía/normas , Reproducibilidad de los Resultados , Reino Unido , Estados Unidos
5.
Nucleic Acids Res ; 52(D1): D33-D43, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37994677

RESUMEN

The National Center for Biotechnology Information (NCBI) provides online information resources for biology, including the GenBank® nucleic acid sequence database and the PubMed® database of citations and abstracts published in life science journals. NCBI provides search and retrieval operations for most of these data from 35 distinct databases. The E-utilities serve as the programming interface for most of these databases. Resources receiving significant updates in the past year include PubMed, PMC, Bookshelf, SciENcv, the NIH Comparative Genomics Resource (CGR), NCBI Virus, SRA, RefSeq, foreign contamination screening tools, Taxonomy, iCn3D, ClinVar, GTR, MedGen, dbSNP, ALFA, ClinicalTrials.gov, Pathogen Detection, antimicrobial resistance resources, and PubChem. These resources can be accessed through the NCBI home page at https://www.ncbi.nlm.nih.gov.


Asunto(s)
Bases de Datos Genéticas , National Library of Medicine (U.S.) , Biotecnología/instrumentación , Bases de Datos de Ácidos Nucleicos , Internet , Estados Unidos
6.
Proc Natl Acad Sci U S A ; 120(25): e2301727120, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37307460

RESUMEN

Poaching for horns and tusks is driving declines of megaherbivores worldwide, including the critically endangered African black rhinoceros (Diceros bicornis). By proactively dehorning entire rhinoceros populations, conservationists aim to deter poaching and prevent species loss. However, such conservation interventions may have hidden and underestimated effects on animals' behavior and ecology. Here, we combine >15 y of black rhino-monitoring data across 10 South African game reserves, comprising >24,000 sightings of 368 individuals, to determine the consequences of dehorning for black rhino space use and social interactions. While preventative dehorning at these reserves coincided with a nationwide decrease in black rhino mortality from poaching and did not infer increased natural mortality, dehorned black rhinos decreased their home range area by, on average, 11.7 km2 (45.5%) and were 37% less likely to engage in social encounters. We conclude that dehorning black rhinos as an antipoaching measure alters their behavioral ecology, although the potential population-level effects of these changes remain to be determined.


Asunto(s)
Fenómenos de Retorno al Lugar Habitual , Perisodáctilos , Interacción Social , Animales , Conducta Animal
7.
Nucleic Acids Res ; 51(D1): D29-D38, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36370100

RESUMEN

The National Center for Biotechnology Information (NCBI) provides online information resources for biology, including the GenBank® nucleic acid sequence database and the PubMed® database of citations and abstracts published in life science journals. NCBI provides search and retrieval operations for most of these data from 35 distinct databases. The E-utilities serve as the programming interface for most of these databases. New resources include the Comparative Genome Resource (CGR) and the BLAST ClusteredNR database. Resources receiving significant updates in the past year include PubMed, PMC, Bookshelf, IgBLAST, GDV, RefSeq, NCBI Virus, GenBank type assemblies, iCn3D, ClinVar, GTR, dbGaP, ALFA, ClinicalTrials.gov, Pathogen Detection, antimicrobial resistance resources, and PubChem. These resources can be accessed through the NCBI home page at https://www.ncbi.nlm.nih.gov.


Asunto(s)
Bases de Datos Genéticas , Bases de Datos de Ácidos Nucleicos , Estados Unidos , National Library of Medicine (U.S.) , Alineación de Secuencia , Biotecnología , Internet
8.
Circulation ; 148(10): 808-818, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37463608

RESUMEN

BACKGROUND: In hypertrophic cardiomyopathy (HCM), myocyte disarray and microvascular disease (MVD) have been implicated in adverse events, and recent evidence suggests that these may occur early. As novel therapy provides promise for disease modification, detection of phenotype development is an emerging priority. To evaluate their utility as early and disease-specific biomarkers, we measured myocardial microstructure and MVD in 3 HCM groups-overt, either genotype-positive (G+LVH+) or genotype-negative (G-LVH+), and subclinical (G+LVH-) HCM-exploring relationships with electrical changes and genetic substrate. METHODS: This was a multicenter collaboration to study 206 subjects: 101 patients with overt HCM (51 G+LVH+ and 50 G-LVH+), 77 patients with G+LVH-, and 28 matched healthy volunteers. All underwent 12-lead ECG, quantitative perfusion cardiac magnetic resonance imaging (measuring myocardial blood flow, myocardial perfusion reserve, and perfusion defects), and cardiac diffusion tensor imaging measuring fractional anisotropy (lower values expected with more disarray), mean diffusivity (reflecting myocyte packing/interstitial expansion), and second eigenvector angle (measuring sheetlet orientation). RESULTS: Compared with healthy volunteers, patients with overt HCM had evidence of altered microstructure (lower fractional anisotropy, higher mean diffusivity, and higher second eigenvector angle; all P<0.001) and MVD (lower stress myocardial blood flow and myocardial perfusion reserve; both P<0.001). Patients with G-LVH+ were similar to those with G+LVH+ but had elevated second eigenvector angle (P<0.001 after adjustment for left ventricular hypertrophy and fibrosis). In overt disease, perfusion defects were found in all G+ but not all G- patients (100% [51/51] versus 82% [41/50]; P=0.001). Patients with G+LVH- compared with healthy volunteers similarly had altered microstructure, although to a lesser extent (all diffusion tensor imaging parameters; P<0.001), and MVD (reduced stress myocardial blood flow [P=0.015] with perfusion defects in 28% versus 0 healthy volunteers [P=0.002]). Disarray and MVD were independently associated with pathological electrocardiographic abnormalities in both overt and subclinical disease after adjustment for fibrosis and left ventricular hypertrophy (overt: fractional anisotropy: odds ratio for an abnormal ECG, 3.3, P=0.01; stress myocardial blood flow: odds ratio, 2.8, P=0.015; subclinical: fractional anisotropy odds ratio, 4.0, P=0.001; myocardial perfusion reserve odds ratio, 2.2, P=0.049). CONCLUSIONS: Microstructural alteration and MVD occur in overt HCM and are different in G+ and G- patients. Both also occur in the absence of hypertrophy in sarcomeric mutation carriers, in whom changes are associated with electrocardiographic abnormalities. Measurable changes in myocardial microstructure and microvascular function are early-phenotype biomarkers in the emerging era of disease-modifying therapy.


Asunto(s)
Cardiomiopatía Hipertrófica , Hipertrofia Ventricular Izquierda , Humanos , Sarcómeros/genética , Imagen de Difusión Tensora , Predisposición Genética a la Enfermedad , Mutación , Cardiomiopatía Hipertrófica/diagnóstico , Fenotipo , Biomarcadores , Fibrosis
9.
J Pediatr ; 267: 113897, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38171471

RESUMEN

OBJECTIVE: To assess the relationships between (1) environmental and demographic factors and executive function (EF) in preschool children with congenital heart disease (CHD) and controls and (2) clinical and surgical risk factors and EF in preschool children with CHD. STUDY DESIGN: At 4-6 years of age, parents of children with CHD (n = 51) and controls (n = 124) completed the Behavior Rating Inventory of Executive Function, Preschool Version questionnaire and the Cognitively Stimulating Parenting Scale (CSPS). Multivariable general linear modeling assessed the relationship between Behavior Rating Inventory of Executive Function, Preschool Version composite scores (Inhibitory Self-Control Index [ISCI], Flexibility Index [FI], and Emergent Metacognition Index [EMI]) and group (CHD/control), sex, age at assessment, gestational age, Index of Multiple Deprivation, and CSPS scores. The relationships between CHD type, surgical factors, and brain magnetic resonance imaging injury rating and ISCI, FI, and EMI scores were assessed. RESULTS: The presence of CHD, age at assessment, sex, and Index of Multiple Deprivation were not associated with EF scores. Lower gestational age was associated with greater ISCI and FI scores, and age at assessment was associated with lower FI scores. Group significantly moderated the relationship between CSPS and EF, such that CSPS significantly predicted EF in children with CHD (ISCI: P = .0004; FI: P = .0015; EMI: P = .0004) but not controls (ISCI: P = .2727; FI: P = .6185; EMI: P = .3332). There were no significant relationships between EF scores and surgical factors, CHD type, or brain magnetic resonance imaging injury rating. CONCLUSIONS: Supporting parents to provide a cognitively stimulating home environment may improve EF in children with CHD. The home and parenting environment should be considered when designing intervention studies aimed at improving EF in this patient group.


Asunto(s)
Función Ejecutiva , Cardiopatías Congénitas , Humanos , Preescolar , Ambiente en el Hogar , Responsabilidad Parental , Padres , Cardiopatías Congénitas/complicaciones
10.
J Pediatr ; 266: 113838, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37995930

RESUMEN

OBJECTIVE: To examine the relationship between perioperative brain injury and neurodevelopment during early childhood in patients with severe congenital heart disease (CHD). STUDY DESIGN: One hundred and seventy children with CHD and born at term who required cardiopulmonary bypass surgery in the first 6 weeks after birth were recruited from 3 European centers and underwent preoperative and postoperative brain MRIs. Uniform description of imaging findings was performed and an overall brain injury score was created, based on the sum of the worst preoperative or postoperative brain injury subscores. Motor and cognitive outcomes were assessed with the Bayley Scales of Infant and Toddler Development Third Edition at 12 to 30 months of age. The relationship between brain injury score and clinical outcome was assessed using multiple linear regression analysis, adjusting for CHD severity, length of hospital stay (LOS), socioeconomic status (SES), and age at follow-up. RESULTS: Neither the overall brain injury score nor any of the brain injury subscores correlated with motor or cognitive outcome. The number of preoperative white matter lesions was significantly associated with gross motor outcome after correction for multiple testing (P = .013, ß = -0.50). SES was independently associated with cognitive outcome (P < .001, ß = 0.26), and LOS with motor outcome (P < .001, ß = -0.35). CONCLUSION: Preoperative white matter lesions appear to be the most predictive MRI marker for adverse early childhood gross motor outcome in this large European cohort of infants with severe CHD. LOS as a marker of disease severity, and SES influence outcome and future intervention trials need to address these risk factors.


Asunto(s)
Lesiones Encefálicas , Cardiopatías Congénitas , Lactante , Humanos , Preescolar , Encéfalo/patología , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Imagen por Resonancia Magnética , Factores de Riesgo
11.
Int J Mol Sci ; 25(2)2024 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-38255817

RESUMEN

Demyelination in the central nervous system (CNS) resulting from injury or disease can cause loss of nerve function and paralysis. Cell therapies intended to promote remyelination of axons are a promising avenue of treatment, with mesenchymal stromal cells (MSCs) a prominent candidate. We have previously demonstrated that MSCs derived from human olfactory mucosa (hOM-MSCs) promote myelination to a greater extent than bone marrow-derived MSCs (hBM-MSCs). However, hOM-MSCs were developed using methods and materials that were not good manufacturing practice (GMP)-compliant. Before considering these cells for clinical use, it is necessary to develop a method for their isolation and expansion that is readily adaptable to a GMP-compliant environment. We demonstrate here that hOM-MSCs can be derived without enzymatic tissue digestion or cell sorting and without culture antibiotics. They grow readily in GMP-compliant media and express typical MSC surface markers. They robustly produce CXCL12 (a key secretory factor in promoting myelination) and are pro-myelinating in in vitro rodent CNS cultures. GMP-compliant hOM-MSCs are comparable in this respect to those grown in non-GMP conditions. However, when assessed in an in vivo model of demyelinating disease (experimental autoimmune encephalitis, EAE), they do not significantly improve disease scores compared with controls, indicating further pre-clinical evaluation is necessary before their advancement to clinical trials.


Asunto(s)
Antibacterianos , Células Madre Mesenquimatosas , Humanos , Técnicas de Cultivo , Axones , Transporte Biológico
12.
Biophys J ; 122(11): 2203-2215, 2023 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-36604961

RESUMEN

The precise spatiotemporal control of nanoscale membrane shape and composition is the result of a complex interplay of individual and collective molecular behaviors. Here, we employed single-molecule localization microscopy and computational simulations to observe single-lipid diffusion and sorting in model membranes with varying compositions, phases, temperatures, and curvatures. Supported lipid bilayers were created over 50-nm-radius nanoparticles to mimic the size of naturally occurring membrane buds, such as endocytic pits and the formation of viral envelopes. The curved membranes recruited liquid-disordered lipid phases while altering the diffusion and sorting of tracer lipids. Disorder-preferring fluorescent lipids sorted to and experienced faster diffusion on the nanoscale curvature only when embedded in a membrane capable of sustaining lipid phase separation at low temperatures. The curvature-induced sorting and faster diffusion even occurred when the sample temperature was above the miscibility temperature of the planar membrane, implying that the nanoscale curvature could induce phase separation in otherwise homogeneous membranes. Further confirmation and understanding of these results are provided by continuum and coarse-grained molecular dynamics simulations with explicit and spontaneous curvature-phase coupling, respectively. The curvature-induced membrane compositional heterogeneity and altered dynamics were achieved only with a coupling of the curvature with a lipid phase separation. These cross-validating results demonstrate the complex interplay of lipid phases, molecular diffusion, and nanoscale membrane curvature that are critical for membrane functionality.


Asunto(s)
Membrana Dobles de Lípidos , Simulación de Dinámica Molecular , Temperatura , Difusión , Transporte de Proteínas , Membrana Celular
13.
J Am Chem Soc ; 145(1): 17-24, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36548788

RESUMEN

Selective functional group interconversions in complex molecular settings underpin many of the challenges facing modern organic synthesis. Currently, a privileged subset of functional groups dominates this landscape, while others, despite their abundance, are sorely underdeveloped. Amines epitomize this dichotomy; they are abundant but otherwise intransigent toward direct interconversion. Here, we report an approach that enables the direct conversion of amines to bromides, chlorides, iodides, phosphates, thioethers, and alcohols, the heart of which is a deaminative carbon-centered radical formation process using an anomeric amide reagent. Experimental and computational mechanistic studies demonstrate that successful deaminative functionalization relies not only on outcompeting the H-atom transfer to the incipient radical but also on the generation of polarity-matched, productive chain-carrying radicals that continue to react efficiently. The overall implications of this technology for interconverting amine libraries were evaluated via high-throughput parallel synthesis and applied in the development of one-pot diversification protocols.


Asunto(s)
Amidas , Aminas , Catálisis , Bromuros , Cloruros
14.
Am J Emerg Med ; 74: 14-16, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37734202

RESUMEN

OBJECTIVE: Transesophageal echocardiography (TEE) is becoming increasingly utilized by emergency medicine providers during cardiac arrest. Intra-arrest, TEE confers several benefits including shorter pauses in chest compressions and direct visualization of cardiac compressions. Many ultrasound probe manufacturers recommend against performing defibrillation with the TEE probe in the mid-esophagus for fear of causing esophageal injury or damage to the probe, however no literature exists that has investigated this concern. To assess this, we performed cardiopulmonary resuscitation (CPR) and multiple defibrillations in 8 swine with a TEE probe in place. METHODS: We performed TEE on 8 adult swine during CPR and performed multiple 200 J defibrillations with the TEE probe in the mid-esophagus. Post-mortem, esophagi were dissected and inspected for evidence of injury. RESULTS: On macroscopic inspection of 8 esophagi, no evidence of hematoma, thermal injury, or perforation was noted. CONCLUSION: Our study suggests that performing defibrillation during CPR with a TEE probe in place in the mid-esophagus is likely safe and low risk for significant esophageal injury. This further bolsters the use of TEE in CPR and would enable continuous visualization of cardiac activity without the need to remove the TEE probe for defibrillation.


Asunto(s)
Traumatismos Abdominales , Reanimación Cardiopulmonar , Paro Cardíaco , Traumatismos Torácicos , Animales , Porcinos , Reanimación Cardiopulmonar/efectos adversos , Paro Cardíaco/etiología , Paro Cardíaco/terapia , Ecocardiografía Transesofágica , Esófago/diagnóstico por imagen , Tórax
15.
Am J Emerg Med ; 63: 182.e5-182.e7, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36280542

RESUMEN

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is most commonly used to manage non-compressible torso hemorrhage. It is also emerging as a promising treatment for non-traumatic refractory cardiac arrest. Aortic occlusion during chest compressions increases cardio-cerebral perfusion, increasing the potential for sustained return of spontaneous circulation (ROSC) or serving as a bridge to extracorporeal cardiopulmonary resuscitation (ECPR). Optimal patient selection and post-ROSC management in such cases is uncertain and not well reported in the literature. We present a case of non-traumatic out-of-hospital cardiac arrest in which REBOA was placed in the emergency department with subsequent ROSC. Transesophageal echocardiography was used to guide post-ROSC REBOA management and balloon deflation.


Asunto(s)
Oclusión con Balón , Paro Cardíaco , Humanos , Retorno de la Circulación Espontánea , Paro Cardíaco/etiología , Paro Cardíaco/terapia
16.
Proc Natl Acad Sci U S A ; 117(26): 14978-14986, 2020 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-32554490

RESUMEN

AB5 bacterial toxins and polyomaviruses induce membrane curvature as a mechanism to facilitate their entry into host cells. How membrane bending is accomplished is not yet fully understood but has been linked to the simultaneous binding of the pentameric B subunit to multiple copies of glycosphingolipid receptors. Here, we probe the toxin membrane binding and internalization mechanisms by using a combination of superresolution and polarized localization microscopy. We show that cholera toxin subunit B (CTxB) can induce membrane curvature only when bound to multiple copies of its glycosphingolipid receptor, GM1, and the ceramide structure of GM1 is likely not a determinant of this activity as assessed in model membranes. A mutant CTxB capable of binding only a single GM1 fails to generate curvature either in model membranes or in cells, and clustering the mutant CTxB-single-GM1 complexes by antibody cross-linking does not rescue the membrane curvature phenotype. We conclude that both the multiplicity and specific geometry of GM1 binding sites are necessary for the induction of membrane curvature. We expect this to be a general rule of membrane behavior for all AB5 toxins and polyomaviruses that bind glycosphingolipids to invade host cells.


Asunto(s)
Membrana Celular/química , Membrana Celular/efectos de los fármacos , Toxina del Cólera/farmacología , Receptores de Superficie Celular/metabolismo , Animales , Células COS , Membrana Celular/metabolismo , Chlorocebus aethiops , Receptores de Superficie Celular/genética
17.
J Med Internet Res ; 25: e39742, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36626192

RESUMEN

BACKGROUND: The rhetoric surrounding clinical artificial intelligence (AI) often exaggerates its effect on real-world care. Limited understanding of the factors that influence its implementation can perpetuate this. OBJECTIVE: In this qualitative systematic review, we aimed to identify key stakeholders, consolidate their perspectives on clinical AI implementation, and characterize the evidence gaps that future qualitative research should target. METHODS: Ovid-MEDLINE, EBSCO-CINAHL, ACM Digital Library, Science Citation Index-Web of Science, and Scopus were searched for primary qualitative studies on individuals' perspectives on any application of clinical AI worldwide (January 2014-April 2021). The definition of clinical AI includes both rule-based and machine learning-enabled or non-rule-based decision support tools. The language of the reports was not an exclusion criterion. Two independent reviewers performed title, abstract, and full-text screening with a third arbiter of disagreement. Two reviewers assigned the Joanna Briggs Institute 10-point checklist for qualitative research scores for each study. A single reviewer extracted free-text data relevant to clinical AI implementation, noting the stakeholders contributing to each excerpt. The best-fit framework synthesis used the Nonadoption, Abandonment, Scale-up, Spread, and Sustainability (NASSS) framework. To validate the data and improve accessibility, coauthors representing each emergent stakeholder group codeveloped summaries of the factors most relevant to their respective groups. RESULTS: The initial search yielded 4437 deduplicated articles, with 111 (2.5%) eligible for inclusion (median Joanna Briggs Institute 10-point checklist for qualitative research score, 8/10). Five distinct stakeholder groups emerged from the data: health care professionals (HCPs), patients, carers and other members of the public, developers, health care managers and leaders, and regulators or policy makers, contributing 1204 (70%), 196 (11.4%), 133 (7.7%), 129 (7.5%), and 59 (3.4%) of 1721 eligible excerpts, respectively. All stakeholder groups independently identified a breadth of implementation factors, with each producing data that were mapped between 17 and 24 of the 27 adapted Nonadoption, Abandonment, Scale-up, Spread, and Sustainability subdomains. Most of the factors that stakeholders found influential in the implementation of rule-based clinical AI also applied to non-rule-based clinical AI, with the exception of intellectual property, regulation, and sociocultural attitudes. CONCLUSIONS: Clinical AI implementation is influenced by many interdependent factors, which are in turn influenced by at least 5 distinct stakeholder groups. This implies that effective research and practice of clinical AI implementation should consider multiple stakeholder perspectives. The current underrepresentation of perspectives from stakeholders other than HCPs in the literature may limit the anticipation and management of the factors that influence successful clinical AI implementation. Future research should not only widen the representation of tools and contexts in qualitative research but also specifically investigate the perspectives of all stakeholder HCPs and emerging aspects of non-rule-based clinical AI implementation. TRIAL REGISTRATION: PROSPERO (International Prospective Register of Systematic Reviews) CRD42021256005; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=256005. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/33145.


Asunto(s)
Inteligencia Artificial , Aprendizaje Automático , Humanos , Personal de Salud , Investigación Cualitativa
18.
Pediatr Emerg Care ; 39(8): 555-561, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-36811547

RESUMEN

OBJECTIVES: Patients with multisystem inflammatory disease in children (MIS-C) are at risk of developing shock. Our objectives were to determine independent predictors associated with development of delayed shock (≥3 hours from emergency department [ED] arrival) in patients with MIS-C and to derive a model predicting those at low risk for delayed shock. METHODS: We conducted a retrospective cross-sectional study of 22 pediatric EDs in the New York City tri-state area. We included patients meeting World Health Organization criteria for MIS-C and presented April 1 to June 30, 2020. Our main outcomes were to determine the association between clinical and laboratory factors to the development of delayed shock and to derive a laboratory-based prediction model based on identified independent predictors. RESULTS: Of 248 children with MIS-C, 87 (35%) had shock and 58 (66%) had delayed shock. A C-reactive protein (CRP) level greater than 20 mg/dL (adjusted odds ratio [aOR], 5.3; 95% confidence interval [CI], 2.4-12.1), lymphocyte percent less than 11% (aOR, 3.8; 95% CI, 1.7-8.6), and platelet count less than 220,000/uL (aOR, 4.2; 95% CI, 1.8-9.8) were independently associated with delayed shock. A prediction model including a CRP level less than 6 mg/dL, lymphocyte percent more than 20%, and platelet count more than 260,000/uL, categorized patients with MIS-C at low risk of developing delayed shock (sensitivity 93% [95% CI, 66-100], specificity 38% [95% CI, 22-55]). CONCLUSIONS: Serum CRP, lymphocyte percent, and platelet count differentiated children at higher and lower risk for developing delayed shock. Use of these data can stratify the risk of progression to shock in patients with MIS-C, providing situational awareness and helping guide their level of care.


Asunto(s)
COVID-19 , Choque , Niño , Humanos , Ciudad de Nueva York/epidemiología , Estudios Retrospectivos , Estudios Transversales , Síndrome de Respuesta Inflamatoria Sistémica
19.
Scand J Psychol ; 64(3): 352-367, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36510394

RESUMEN

This archival study was the first in Sweden, and the first outside of the US and the UK, to apply the (Kelly et al., Psychology, Public Policy, and Law, 9, 165-178, 2013) taxonomy of interrogation methods framework to repeated police interrogations of adult suspects in high-stakes crimes. Audio/video recordings (N = 19) were collected from the Swedish Police Authority of repeated interrogations of three suspects in three criminal cases. The interaction between interrogators and suspects were scored according to the taxonomy framework (Kelly et al., Psychology, Public Policy, and Law, 9, 165-178, 2013; Kelly et al., Law and Human Behavior, 40, 295-309, 2016). First, there was an association between the use of different domains. Rapport and relationship building was moderately and negatively associated with confrontation/competition and presentation of evidence. Moreover, confrontation/competition was moderately and positively related to emotion provocation and presentation of evidence. Second, changes were observed during the interrogations. Presentation of evidence was lower in the beginning than in the middle block. Suspect cooperation was higher in the beginning than both the middle and end blocks. Third, an ordered logistic regression showed that rapport and relationship building were associated with increased suspect cooperation, and confrontation/competition and presentation of evidence were associated with decreased cooperation. The study's results are mostly in line with other taxonomy studies on high-stakes crimes from the US and the UK. The findings are discussed in light of theoretical frameworks, empirical findings, and current police practice. We also highlight the need for further research.


Asunto(s)
Crimen , Policia , Adulto , Humanos , Suecia , Policia/psicología , Crimen/psicología , Emociones , Relaciones Interpersonales
20.
Stroke ; 53(12): 3652-3661, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36300371

RESUMEN

BACKGROUND: Infants with congenital heart disease are at risk of brain injury and impaired neurodevelopment. The aim was to investigate risk factors for perioperative brain lesions in infants with congenital heart disease. METHODS: Infants with transposition of the great arteries, single ventricle physiology, and left ventricular outflow tract and/or aortic arch obstruction undergoing cardiac surgery <6 weeks after birth from 3 European cohorts (Utrecht, Zurich, and London) were combined. Brain lesions were scored on preoperative (transposition of the great arteries N=104; single ventricle physiology N=35; and left ventricular outflow tract and/or aortic arch obstruction N=41) and postoperative (transposition of the great arteries N=88; single ventricle physiology N=28; and left ventricular outflow tract and/or aortic arch obstruction N=30) magnetic resonance imaging for risk factor analysis of arterial ischemic stroke, cerebral sinus venous thrombosis, and white matter injury. RESULTS: Preoperatively, induced vaginal delivery (odds ratio [OR], 2.23 [95% CI, 1.06-4.70]) was associated with white matter injury and balloon atrial septostomy increased the risk of white matter injury (OR, 2.51 [95% CI, 1.23-5.20]) and arterial ischemic stroke (OR, 4.49 [95% CI, 1.20-21.49]). Postoperatively, younger postnatal age at surgery (OR, 1.18 [95% CI, 1.05-1.33]) and selective cerebral perfusion, particularly at ≤20 °C (OR, 13.46 [95% CI, 3.58-67.10]), were associated with new arterial ischemic stroke. Single ventricle physiology was associated with new white matter injury (OR, 2.88 [95% CI, 1.20-6.95]) and transposition of the great arteries with new cerebral sinus venous thrombosis (OR, 13.47 [95% CI, 2.28-95.66]). Delayed sternal closure (OR, 3.47 [95% CI, 1.08-13.06]) and lower intraoperative temperatures (OR, 1.22 [95% CI, 1.07-1.36]) also increased the risk of new cerebral sinus venous thrombosis. CONCLUSIONS: Delivery planning and surgery timing may be modifiable risk factors that allow personalized treatment to minimize the risk of perioperative brain injury in severe congenital heart disease. Further research is needed to optimize cerebral perfusion techniques for neonatal surgery and to confirm the relationship between cerebral sinus venous thrombosis and perioperative risk factors.


Asunto(s)
Lesiones Encefálicas , Cardiopatías Congénitas , Accidente Cerebrovascular Isquémico , Transposición de los Grandes Vasos , Trombosis de la Vena , Lactante , Recién Nacido , Femenino , Humanos , Transposición de los Grandes Vasos/cirugía , Transposición de los Grandes Vasos/complicaciones , Transposición de los Grandes Vasos/patología , Cardiopatías Congénitas/epidemiología , Cardiopatías Congénitas/cirugía , Cardiopatías Congénitas/complicaciones , Factores de Riesgo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Lesiones Encefálicas/patología , Trombosis de la Vena/complicaciones
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