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Glycans modify lipids and proteins to mediate inter- and intramolecular interactions across all domains of life. RNA is not thought to be a major target of glycosylation. Here, we challenge this view with evidence that mammals use RNA as a third scaffold for glycosylation. Using a battery of chemical and biochemical approaches, we found that conserved small noncoding RNAs bear sialylated glycans. These "glycoRNAs" were present in multiple cell types and mammalian species, in cultured cells, and in vivo. GlycoRNA assembly depends on canonical N-glycan biosynthetic machinery and results in structures enriched in sialic acid and fucose. Analysis of living cells revealed that the majority of glycoRNAs were present on the cell surface and can interact with anti-dsRNA antibodies and members of the Siglec receptor family. Collectively, these findings suggest the existence of a direct interface between RNA biology and glycobiology, and an expanded role for RNA in extracellular biology.
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Membrana Celular/metabolismo , Polisacáridos/metabolismo , ARN/metabolismo , Animales , Anticuerpos/metabolismo , Secuencia de Bases , Vías Biosintéticas , Línea Celular , Supervivencia Celular , Humanos , Espectrometría de Masas , Ácido N-Acetilneuramínico/metabolismo , Poliadenilación , Polisacáridos/química , ARN/química , ARN/genética , ARN no Traducido/metabolismo , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismo , Coloración y EtiquetadoRESUMEN
The capacity for terrestrial ecosystems to sequester additional carbon (C) with rising CO2 concentrations depends on soil nutrient availability1,2. Previous evidence suggested that mature forests growing on phosphorus (P)-deprived soils had limited capacity to sequester extra biomass under elevated CO2 (refs. 3-6), but uncertainty about ecosystem P cycling and its CO2 response represents a crucial bottleneck for mechanistic prediction of the land C sink under climate change7. Here, by compiling the first comprehensive P budget for a P-limited mature forest exposed to elevated CO2, we show a high likelihood that P captured by soil microorganisms constrains ecosystem P recycling and availability for plant uptake. Trees used P efficiently, but microbial pre-emption of mineralized soil P seemed to limit the capacity of trees for increased P uptake and assimilation under elevated CO2 and, therefore, their capacity to sequester extra C. Plant strategies to stimulate microbial P cycling and plant P uptake, such as increasing rhizosphere C release to soil, will probably be necessary for P-limited forests to increase C capture into new biomass. Our results identify the key mechanisms by which P availability limits CO2 fertilization of tree growth and will guide the development of Earth system models to predict future long-term C storage.
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Dióxido de Carbono , Secuestro de Carbono , Bosques , Fósforo , Microbiología del Suelo , Árboles , Biomasa , Dióxido de Carbono/metabolismo , Dióxido de Carbono/análisis , Fósforo/metabolismo , Rizosfera , Suelo/química , Árboles/crecimiento & desarrollo , Árboles/metabolismo , Cambio ClimáticoRESUMEN
To maintain a stable and clear image of the world, our eyes reflexively follow the direction in which a visual scene is moving. Such gaze-stabilization mechanisms reduce image blur as we move in the environment. In non-primate mammals, this behaviour is initiated by retinal output neurons called ON-type direction-selective ganglion cells (ON-DSGCs), which detect the direction of image motion and transmit signals to brainstem nuclei that drive compensatory eye movements1. However, ON-DSGCs have not yet been identified in the retina of primates, raising the possibility that this reflex is mediated by cortical visual areas. Here we mined single-cell RNA transcriptomic data from primate retina to identify a candidate ON-DSGC. We then combined two-photon calcium imaging, molecular identification and morphological analysis to reveal a population of ON-DSGCs in the macaque retina. The morphology, molecular signature and GABA (γ-aminobutyric acid)-dependent mechanisms that underlie direction selectivity in primate ON-DSGCs are highly conserved with those in other mammals. We further identify a candidate ON-DSGC in human retina. The presence of ON-DSGCs in primates highlights the need to examine the contribution of subcortical retinal mechanisms to normal and aberrant gaze stabilization in the developing and mature visual system.
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Movimientos Oculares , Macaca , Retina , Células Ganglionares de la Retina , Animales , Humanos , Movimientos Oculares/fisiología , Estimulación Luminosa , Retina/citología , Retina/fisiología , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/fisiología , Movimiento (Física) , Análisis de Expresión Génica de una Sola Célula , Ácido gamma-Aminobutírico/metabolismo , Señalización del Calcio , Fijación Ocular/fisiologíaRESUMEN
Atmospheric carbon dioxide enrichment (eCO2) can enhance plant carbon uptake and growth1-5, thereby providing an important negative feedback to climate change by slowing the rate of increase of the atmospheric CO2 concentration6. Although evidence gathered from young aggrading forests has generally indicated a strong CO2 fertilization effect on biomass growth3-5, it is unclear whether mature forests respond to eCO2 in a similar way. In mature trees and forest stands7-10, photosynthetic uptake has been found to increase under eCO2 without any apparent accompanying growth response, leaving the fate of additional carbon fixed under eCO2 unclear4,5,7-11. Here using data from the first ecosystem-scale Free-Air CO2 Enrichment (FACE) experiment in a mature forest, we constructed a comprehensive ecosystem carbon budget to track the fate of carbon as the forest responded to four years of eCO2 exposure. We show that, although the eCO2 treatment of +150 parts per million (+38 per cent) above ambient levels induced a 12 per cent (+247 grams of carbon per square metre per year) increase in carbon uptake through gross primary production, this additional carbon uptake did not lead to increased carbon sequestration at the ecosystem level. Instead, the majority of the extra carbon was emitted back into the atmosphere via several respiratory fluxes, with increased soil respiration alone accounting for half of the total uptake surplus. Our results call into question the predominant thinking that the capacity of forests to act as carbon sinks will be generally enhanced under eCO2, and challenge the efficacy of climate mitigation strategies that rely on ubiquitous CO2 fertilization as a driver of increased carbon sinks in global forests.
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Atmósfera/química , Dióxido de Carbono/análisis , Dióxido de Carbono/metabolismo , Secuestro de Carbono , Bosques , Árboles/metabolismo , Biomasa , Eucalyptus/crecimiento & desarrollo , Eucalyptus/metabolismo , Calentamiento Global/prevención & control , Modelos Biológicos , Nueva Gales del Sur , Fotosíntesis , Suelo/química , Árboles/crecimiento & desarrolloRESUMEN
Cell size and cell count are adaptively regulated and intimately linked to growth and function. Yet, despite their widespread relevance, the relation between cell size and count has never been formally examined over the whole human body. Here, we compile a comprehensive dataset of cell size and count over all major cell types, with data drawn from >1,500 published sources. We consider the body of a representative male (70 kg), which allows further estimates of a female (60 kg) and 10-y-old child (32 kg). We build a hierarchical interface for the cellular organization of the body, giving easy access to data, methods, and sources (https://humancelltreemap.mis.mpg.de/). In total, we estimate total body counts of ≈36 trillion cells in the male, ≈28 trillion in the female, and ≈17 trillion in the child. These data reveal a surprising inverse relation between cell size and count, implying a trade-off between these variables, such that all cells within a given logarithmic size class contribute an equal fraction to the body's total cellular biomass. We also find that the coefficient of variation is approximately independent of mean cell size, implying the existence of cell-size regulation across cell types. Our data serve to establish a holistic quantitative framework for the cells of the human body, and highlight large-scale patterns in cell biology.
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Recuento de Células , Niño , Humanos , Femenino , Masculino , Biomasa , Tamaño de la Célula , Correlación de DatosRESUMEN
The Siglecs (sialic acid-binding immunoglobulin-like lectins) are glycoimmune checkpoint receptors that suppress immune cell activation upon engagement of cognate sialoglycan ligands. The cellular drivers underlying Siglec ligand production on cancer cells are poorly understood. We find the MYC oncogene causally regulates Siglec ligand production to enable tumor immune evasion. A combination of glycomics and RNA-sequencing of mouse tumors revealed the MYC oncogene controls expression of the sialyltransferase St6galnac4 and induces a glycan known as disialyl-T. Using in vivo models and primary human leukemias, we find that disialyl-T functions as a "don't eat me" signal by engaging macrophage Siglec-E in mice or the human ortholog Siglec-7, thereby preventing cancer cell clearance. Combined high expression of MYC and ST6GALNAC4 identifies patients with high-risk cancers and reduced tumor myeloid infiltration. MYC therefore regulates glycosylation to enable tumor immune evasion. We conclude that disialyl-T is a glycoimmune checkpoint ligand. Thus, disialyl-T is a candidate for antibody-based checkpoint blockade, and the disialyl-T synthase ST6GALNAC4 is a potential enzyme target for small molecule-mediated immune therapy.
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Neoplasias , Proteínas Proto-Oncogénicas c-myc , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico , Animales , Humanos , Ratones , Antígenos CD/metabolismo , Ligandos , Macrófagos/metabolismo , Neoplasias/metabolismo , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismoRESUMEN
Microglia maintain homeostasis in the central nervous system through phagocytic clearance of protein aggregates and cellular debris. This function deteriorates during ageing and neurodegenerative disease, concomitant with cognitive decline. However, the mechanisms of impaired microglial homeostatic function and the cognitive effects of restoring this function remain unknown. We combined CRISPR-Cas9 knockout screens with RNA sequencing analysis to discover age-related genetic modifiers of microglial phagocytosis. These screens identified CD22, a canonical B cell receptor, as a negative regulator of phagocytosis that is upregulated on aged microglia. CD22 mediates the anti-phagocytic effect of α2,6-linked sialic acid, and inhibition of CD22 promotes the clearance of myelin debris, amyloid-ß oligomers and α-synuclein fibrils in vivo. Long-term central nervous system delivery of an antibody that blocks CD22 function reprograms microglia towards a homeostatic transcriptional state and improves cognitive function in aged mice. These findings elucidate a mechanism of age-related microglial impairment and a strategy to restore homeostasis in the ageing brain.
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Envejecimiento/fisiología , Encéfalo/citología , Homeostasis/efectos de los fármacos , Microglía/efectos de los fármacos , Ácido N-Acetilneuramínico/farmacología , Fagocitosis/efectos de los fármacos , Lectina 2 Similar a Ig de Unión al Ácido Siálico/antagonistas & inhibidores , Envejecimiento/efectos de los fármacos , Envejecimiento/genética , Animales , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Cognición/efectos de los fármacos , Cognición/fisiología , Femenino , Homeostasis/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía/citología , Ácido N-Acetilneuramínico/química , Fagocitosis/genética , Análisis de Secuencia de ARN , Lectina 2 Similar a Ig de Unión al Ácido Siálico/genética , Lectina 2 Similar a Ig de Unión al Ácido Siálico/metabolismoRESUMEN
Rationale: Airway tree morphology varies in the general population and may modify the distribution and uptake of inhaled pollutants. Objectives: We hypothesized that smaller airway caliber would be associated with emphysema progression and would increase susceptibility to air pollutant-associated emphysema progression. Methods: MESA (Multi-Ethnic Study of Atherosclerosis) is a general population cohort of adults 45-84 years old from six U.S. communities. Airway tree caliber was quantified as the mean of airway lumen diameters measured from baseline cardiac computed tomography (CT) (2000-2002). Percentage emphysema, defined as percentage of lung pixels below -950 Hounsfield units, was assessed up to five times per participant via cardiac CT scan (2000-2007) and equivalent regions on lung CT scan (2010-2018). Long-term outdoor air pollutant concentrations (particulate matter with an aerodynamic diameter ⩽2.5 µm, oxides of nitrogen, and ozone) were estimated at the residential address with validated spatiotemporal models. Linear mixed models estimated the association between airway tree caliber and emphysema progression; modification of pollutant-associated emphysema progression was assessed using multiplicative interaction terms. Measurements and Main Results: Among 6,793 participants (mean ± SD age, 62 ± 10 yr), baseline airway tree caliber was 3.95 ± 1.1 mm and median (interquartile range) of percentage emphysema was 2.88 (1.21-5.68). In adjusted analyses, 10-year emphysema progression rate was 0.75 percentage points (95% confidence interval, 0.54-0.96%) higher in the smallest compared with largest airway tree caliber quartile. Airway tree caliber also modified air pollutant-associated emphysema progression. Conclusions: Smaller airway tree caliber was associated with accelerated emphysema progression and modified air pollutant-associated emphysema progression. A better understanding of the mechanisms of airway-alveolar homeostasis and air pollutant deposition is needed.
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Contaminantes Atmosféricos , Enfisema Pulmonar , Humanos , Anciano , Masculino , Femenino , Persona de Mediana Edad , Anciano de 80 o más Años , Enfisema Pulmonar/diagnóstico por imagen , Contaminantes Atmosféricos/efectos adversos , Progresión de la Enfermedad , Tomografía Computarizada por Rayos X , Contaminación del Aire/efectos adversos , Estados Unidos/epidemiología , Material Particulado/efectos adversos , Susceptibilidad a Enfermedades , Estudios de CohortesRESUMEN
Rationale Dysanapsis refers to a mismatch between airway tree caliber and lung size arising early in life. Dysanapsis assessed by computed tomography (CT) is evident by early adulthood and associated with chronic obstructive pulmonary disease (COPD) risk later in life. Objective By examining the genetic factors associated with CT-assessed dysanapsis, we aimed to elucidate its molecular underpinnings and physiological significance across the lifespan. Methods We performed a genome-wide association study (GWAS) of CT-assessed dysanapsis in 11,951 adults, including individuals from two population-based and two COPD-enriched studies. We applied colocalization analysis to integrate GWAS and gene expression data from whole blood and lung. Genetic variants associated with dysanapsis were combined into a genetic risk score that was applied to examine association with lung function in children from a population-based birth cohort (n=1,278) and adults from the UK Biobank (n=369,157). Measurements and Main Results CT-assessed dysanapsis was associated with genetic variants from 21 independent signals in 19 gene regions, implicating HHIP, DSP, and NPNT as potential molecular targets based on colocalization of their expression. Higher dysanapsis genetic risk score was associated with obstructive spirometry among 5 year old children and among adults in the 5th, 6th and 7th decades of life. Conclusions CT-assessed dysanapsis is associated with variation in genes previously implicated in lung development and dysanapsis genetic risk is associated with obstructive lung function from early life through older adulthood. Dysanapsis may represent an endo-phenotype link between the genetic variations associated with lung function and COPD.
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Tropical forests contribute a major sink for anthropogenic carbon emissions essential to slowing down the buildup of atmospheric CO2 and buffering climate change impacts. However, the response of tropical forests to more frequent weather extremes and long-recovery disturbances like fires remains uncertain. Analyses of field data and ecological theory raise concerns about the possibility of the Amazon crossing a tipping point leading to catastrophic tropical forest loss. In contrast, climate models consistently project an enhanced tropical sink. Here, we show a heterogeneous response of Amazonian carbon stocks in GFDL-ESM4.1, an Earth System Model (ESM) featuring dynamic disturbances and height-structured tree-grass competition. Enhanced productivity due to CO2 fertilization promotes increases in forest biomass that, under low emission scenarios, last until the end of the century. Under high emissions, positive trends reverse after 2060, when simulated fires prompt forest loss that results in a 40% decline in tropical forest biomass by 2100. Projected fires occur under dry conditions associated with El Niño Southern Oscillation and the Atlantic Multidecadal Oscillation, a response observed under current climate conditions, but exacerbated by an overall decline in precipitation. Following the initial disturbance, grassland dominance promotes recurrent fires and tree competitive exclusion, which prevents forest recovery. EC-Earth3-Veg, an ESM with a dynamic vegetation model of similar complexity, projected comparable wildfire forest loss under high emissions but faster postfire recovery rates. Our results reveal the importance of complex nonlinear responses to assessing climate change impacts and the urgent need to research postfire recovery and its representation in ESMs.
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Dióxido de Carbono , Incendios , Bosques , Árboles , Carbono , Cambio ClimáticoRESUMEN
Increasing spike rates drive greater neuronal energy demand. In turn, mitochondrial ATP production leads to the generation of reactive oxygen species (ROS) that can modulate ion channel gating. Does ROS production autoregulate the excitability of a neuron? We investigated the links between retinal ganglion cell (RGC) excitability and spike activity-driven ROS production in male and female mice. Changes to the light-evoked and current-evoked spike patterns of functionally identified αRGC subtypes, along with their NaV channel-gating properties, were recorded during experimentally induced decreases and increases of intracellular ROS. During periods of highest spike rates (e.g., following light onset in ON sustained RGCs and light offset in OFF sustained RGCs), these αRGC subtypes responded to reductions of ROS (induced by catalase or glutathione monoethyl ester) with higher spike rates. Increases in ROS (induced by mercaptosuccinate, antimycin-A, or H2O2) lowered spike rates. In ON and OFF transient RGCs, there were no changes in spike rate during ROS decreases but increased ROS increased spiking. This suggests that endogenous ROS are intrinsic neuromodulators in RGCs having high metabolic demands but not in RGCs with lower energy needs. We identified ROS-induced shifts in the voltage-dependent gating of specific isoforms of NaV channels that account for the modulation of ON and OFF sustained RGC spike frequency by ROS-mediated feedback. ROS-induced changes to NaV channel gating, affecting activation and inactivation kinetics, are consistent with the differing spike pattern alterations observed in RGC subtypes. Cell-autonomous generation of ROS during spiking contributes to tuning the spike patterns of RGCs.SIGNIFICANCE STATEMENT Energy production within retinal ganglion cells (RGCs) is accompanied by metabolic by-products harmful to cellular function. How these by-products modulate the excitability of RGCs bears heavily on visual function and the etiology of optic neuropathies. A novel hypothesis of how RGC metabolism can produce automodulation of electrical signaling was tested by identifying the characteristics and biophysical origins of changes to the excitability of RGCs caused by oxidizing by-products in the retina. This impacts our understanding of the pathophysiology of RGC dysfunction, supporting an emerging model in which increases in oxidizing chemical species during energy production, but not necessarily bioenergetic failure, lead to preferential degeneration of specific subtypes of RGCs, yielding loss of different aspects of visual capacity.
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Peróxido de Hidrógeno , Células Ganglionares de la Retina , Ratones , Femenino , Masculino , Animales , Especies Reactivas de Oxígeno , Células Ganglionares de la Retina/fisiología , Retina , Transducción de SeñalRESUMEN
The Pseudomonas aeruginosa toxin ExoS, secreted by the type III secretion system (T3SS), supports intracellular persistence via its ADP-ribosyltransferase (ADPr) activity. For epithelial cells, this involves inhibiting vacuole acidification, promoting vacuolar escape, countering autophagy, and niche construction in the cytoplasm and within plasma membrane blebs. Paradoxically, ExoS and other P. aeruginosa T3SS effectors can also have antiphagocytic and cytotoxic activities. Here, we sought to reconcile these apparently contradictory activities of ExoS by studying the relationships between intracellular persistence and host epithelial cell death. Methods involved quantitative imaging and the use of antibiotics that vary in host cell membrane permeability to selectively kill intracellular and extracellular populations after invasion. Results showed that intracellular P. aeruginosa mutants lacking T3SS effector toxins could kill (permeabilize) cells when extracellular bacteria were eliminated. Surprisingly, wild-type strain PAO1 (encoding ExoS, ExoT and ExoY) caused cell death more slowly, the time extended from 5.2 to 9.5 h for corneal epithelial cells and from 10.2 to 13.0 h for HeLa cells. Use of specific mutants/complementation and controls for initial invasion showed that ExoS ADPr activity delayed cell death. Triggering T3SS expression only after bacteria invaded cells using rhamnose-induction in T3SS mutants rescued the ExoS-dependent intracellular phenotype, showing that injected effectors from extracellular bacteria were not required. The ADPr activity of ExoS was further found to support internalization by countering the antiphagocytic activity of both the ExoS and ExoT RhoGAP domains. Together, these results show two additional roles for ExoS ADPr activity in supporting the intracellular lifestyle of P. aeruginosa; suppression of host cell death to preserve a replicative niche and inhibition of T3SS effector antiphagocytic activities to allow invasion. These findings add to the growing body of evidence that ExoS-encoding (invasive) P. aeruginosa strains can be facultative intracellular pathogens, and that intracellularly secreted T3SS effectors contribute to pathogenesis.
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ADP Ribosa Transferasas/metabolismo , Permeabilidad de la Membrana Celular , Exotoxinas/metabolismo , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/metabolismo , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Muerte Celular , Células Epiteliales/metabolismo , Células Epiteliales/microbiología , Proteínas Activadoras de GTPasa/metabolismo , Células HeLa , Interacciones Huésped-Patógeno , Humanos , Mutación , Pseudomonas aeruginosa/efectos de los fármacos , Sistemas de Secreción Tipo III/metabolismo , Vacuolas/metabolismoRESUMEN
BACKGROUND: Targeted axillary dissection (TAD) facilitates nodal staging in cN1 breast cancer after neoadjuvant chemotherapy (NAC). Completion axillary node dissection (cALND) remains the standard of care for TAD-positive patients. This study investigated factors associated with additional positive nodes at cALND (cALND+) and the impact on the residual cancer burden (RCB). METHODS: Retrospective review of cN1 breast cancer patients treated with NAC and TAD was conducted from July 2013 to June 2023. The review defined cN1 status by ultrasound (US) and biopsy. Patient, tumor, and treatment characteristics were evaluated. Multivariate analysis was performed to identify factors associated with cALND+, and RCB was calculated. RESULTS: Of 902 patients who underwent TAD, 554 (61.4%) were TAD-positive. 457 underwent cALND, and 124 (27%) were cALND+ (average 4.1 additional +nodes). The cALND+ patients had larger primary tumors at diagnosis (4 vs 3.5 cm; p = 0.04), more than three suspicious nodes on initial US (30% vs 13%; p ≤ 0.0001), larger residual primary tumors on pathology (median, 3 vs 2.1 cm; p = 0.0004), and more positive TAD nodes (median, 2 vs 1; p ≤ 0.0001). In the multivariate analysis, the factors associated with cALND+ were more than three suspicious nodes on initial US (odds ratio [OR], 2.9; p ≤ 0.0001), more positive TAD nodes (OR, 1.1; p ≤ 0.0001), larger clipped node metastasis (OR, 1.1; p ≤ 0.0001), and larger residual tumor on pathology (OR, 1.1; p = 0.006). Of 65 cALND+ patients with RCB class I or II, 29 (45%) had an increase in RCB based on cALND. CONCLUSION: Of cN1 breast cancer patients treated with NAC who are TAD-positive, approximately 25% will have additional nodal disease on cALND. In these patients, positive cALND is associated with greater disease burden, which has potential implications for RCB status and prognosis.
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BACKGROUND: Mucus plugs have been described in the airways of asthmatic subjects, particularly those with associated with type 2 inflammation and sputum eosinophilia. In the current study we addressed the question of whether smoking, neutrophilic inflammation and airway dimensions affected the prevalence of mucus plugs. METHODS: In a cohort of moderate to severe asthmatics (n = 50), including a group of ex-smokers and current smokers, the prevalence of mucus plugs was quantified using a semi-quantitative score based on thoracic computerized tomography. The relationships between mucus score, sputum inflammatory profile and airway architecture were tested according to patient's smoking status. RESULTS: Among the asthmatics (37% former or active smokers), 74% had at least one mucus plug. The median score was 3 and was unrelated to smoking status. A significant but weak correlation was found between mucus score, FEV1 and FEV1/FVC. Mucus score was significantly correlated with sputum eosinophils. Among former and active smokers, mucus score was correlated with sputum neutrophils. Mucus score was positively associated with FeNO in non-smoking subjects. The lumen dimensions of the main and lobar bronchi were significantly inversely correlated with mucus score. CONCLUSION: Airway mucus plugs could define an asthma phenotype with altered airway architecture and can occur in asthmatic subjects with either neutrophilic or eosinophilic sputum according to their smoking status.
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Asma , Humanos , Moco , Esputo , Bronquios , InflamaciónRESUMEN
Point of Care Ultrasound (POCUS) has seen increasing use in the prehospital environment over the last decade, primarily with the extended focused assessment with sonography in trauma (eFAST) exam. Previous studies have shown prehospital eFAST exams are feasible in the helicopter transport environment but have yet to demonstrate effects on clinical care. This retrospective case series identified 655 patients with blunt thoraco-abdominal trauma or concern for pneumothorax due to penetrating injury transported by a single helicopter EMS (HEMS) program over a two-year period after introducing POCUS. Of those patients, 258 received prehospital ultrasound which was reported to change clinical care in seven cases (2.7%, 95%-CI [1.1-5.5]). This was primarily through preventing unnecessary needle thoracostomy and initiating blood transfusion for treatment of hemorrhagic shock in cases where the degree of shock was unclear due to inconsistent vital signs. This study highlights the improvements in clinical care that may result from the introduction of eFAST exams in the prehospital environment.
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Ambulancias Aéreas , Servicios Médicos de Urgencia , Humanos , Estudios Retrospectivos , Masculino , Servicios Médicos de Urgencia/métodos , Femenino , Adulto , Toma de Decisiones Clínicas/métodos , Persona de Mediana Edad , Sistemas de Atención de Punto , Ultrasonografía/métodos , Evaluación Enfocada con Ecografía para Trauma/métodos , Heridas no Penetrantes/diagnóstico , Heridas no Penetrantes/terapiaRESUMEN
Glyco-immune checkpoint receptors, molecules that inhibit immune cell activity following binding to glycosylated cell-surface antigens, are emerging as attractive targets for cancer immunotherapy. Defining biologically relevant ligands that bind and activate such receptors, however, has historically been a significant challenge. Here, we present a CRISPRi genomic screening strategy that allowed unbiased identification of the key genes required for cell-surface presentation of glycan ligands on leukemia cells that bind the glyco-immune checkpoint receptors Siglec-7 and Siglec-9. This approach revealed a selective interaction between Siglec-7 and the mucin-type glycoprotein CD43. Further work identified a specific N-terminal glycopeptide region of CD43 containing clusters of disialylated O-glycan tetrasaccharides that form specific Siglec-7 binding motifs. Knockout or blockade of CD43 in leukemia cells relieves Siglec-7-mediated inhibition of immune killing activity. This work identifies a potential target for immune checkpoint blockade therapy and represents a generalizable approach to dissection of glycan-receptor interactions in living cells.
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Antígenos de Diferenciación Mielomonocítica/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Genoma Humano , Lectinas/metabolismo , Polisacáridos/metabolismo , Secuencias de Aminoácidos , Antígenos de Diferenciación Mielomonocítica/química , Línea Celular Tumoral , Membrana Celular/metabolismo , Glicopéptidos/metabolismo , Humanos , Sinapsis Inmunológicas/metabolismo , Células Asesinas Naturales/metabolismo , Lectinas/química , Leucosialina/química , Leucosialina/metabolismo , Ligandos , Unión ProteicaRESUMEN
PURPOSE: To investigate the biomechanical effects of tape-reinforced graft suturing and graft retensioning for all-soft tissue quadriceps tendon (ASTQT) anterior cruciate ligament reconstruction (ACLR) in a full-construct human cadaveric model. METHODS: Harvested cadaveric ASTQT grafts were assigned to either (1) double-suspensory adjustable-loop cortical button device (ALD) fixation in which both graft ends were fixed with a suspensory fixation device with (n = 5) or without (n = 5) tape-reinforced suturing or (2) single-suspensory distal tendon fixation in which only the patellar end was fixed with an ALD (n = 5) or fixed-loop cortical button device (FLD) (n = 5). All specimens were prepared using a No. 2 whipstitch technique, and tape-reinforced specimens had an integrated braided tape implant. Graft preparation time was recorded for double-suspensory constructs. Samples were tested on an electromechanical testing machine using a previously published protocol simulating rehabilitative kinematics and loading. RESULTS: Tape-reinforced graft suturing resulted in greater graft load retention after cycling (11.9% difference, P = .021), less total elongation (mean [95% confidence interval (CI)], 5.57 mm [3.50-7.65 mm] vs 32.14 mm [25.38-38.90 mm]; P < .001), greater ultimate failure stiffness (mean [95% CI], 171.9 N/mm [158.8-185.0 N/mm] vs 119.4 N/mm [108.7-130.0 N/mm]; P < .001), and less graft preparation time (36.4% difference, P < .001) when compared with unreinforced specimens. Retensioned ALD constructs had less cyclic elongation compared with FLD constructs (mean total elongation [95% CI], 7.04 mm [5.47-8.61 mm] vs 12.96 mm [8.67-17.26 mm]; P = .004). CONCLUSIONS: Tape-reinforced graft suturing improves time-zero ASTQT ACLR construct biomechanics in a cadaveric model with 83% less total elongation, 44% greater stiffness, and reduced preparation time compared with a whipstitched graft without tape reinforcement. ALD fixation improves construct mechanics when compared with FLD fixation as evidenced by 46% less total elongation. CLINICAL RELEVANCE: Tape-reinforced implants and graft retensioning using ALDs improve time-zero ACLR graft construct biomechanics in a time-zero biomechanical model. Clinical studies will be necessary to determine whether these implants improve clinical outcomes including knee laxity and the incidence of graft rupture.
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Reconstrucción del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior , Humanos , Ligamento Cruzado Anterior/cirugía , Fenómenos Biomecánicos , Autoinjertos , Tendones/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , CadáverRESUMEN
The study aimed to evaluate the feasibility of using QR code-enabled medical bracelets for congenital heart disease (CHD) patients after hospital discharge to ensure quick communication of vital information to other medical personnel in emergency situations. A prospective study was conducted where QR code-enabled medical bracelets were given to families of postoperative pediatric cardiac patients. The QR code linked to a secure medical information sheet detailing the patient's cardiac history. Post-study surveys were completed by providers and families to assess their experiences with the bracelet. Of the 20 participants enrolled, 65% used the QR bracelet when seeking medical care. 55% found the bracelet useful, and 70% rated their experience as either "positive" or "very positive". Additionally, 80% recommended the bracelet for other patients undergoing cardiac procedures. The use of QR code bracelets for postoperative CHD patients has shown high levels of satisfaction from families and providers, potentially reducing medical errors and treatment delays.
Asunto(s)
Cardiopatías Congénitas , Humanos , Cardiopatías Congénitas/terapia , Cardiopatías Congénitas/cirugía , Proyectos Piloto , Estudios Prospectivos , Femenino , Masculino , Cuidados Posoperatorios/métodos , Niño , Estudios de Factibilidad , Preescolar , Procedimientos Quirúrgicos Cardíacos , Lactante , Alta del Paciente , Encuestas y CuestionariosRESUMEN
BACKGROUND: The Statin Use in Persons with Diabetes (SUPD) measure is a Star measure by the Center for Medicare & Medicaid Services. The Duke Population Health Management Office (PHMO) has a team of pharmacists and pharmacy students who conduct targeted outreach to patients at risk of failing statin quality measures. Pharmacy services are embedded in select primary care clinics and other clinics are supported remotely. OBJECTIVE: The primary objective of this review is to compare the initiation rates of recommended statin prescriptions between embedded pharmacist vs remote pharmacist vs remote student pharmacist outreach groups, all of which have different levels of autonomy within pharmacy practice. The secondary objectives are to identify the barriers to the implementation of statin therapy and to assess the statin drugs and intensity of the statins prescribed. METHODS: A single-center, retrospective chart review was performed for SUPD patients with Medicare insurance. SUPD patients included patients 40-75 years of age, diagnosed with type 2 diabetes, and were not dispensed at least one statin medication of any intensity during the 6-month measurement period. The primary outcome was the initiation of recommended statin medications prescribed, or pended for the PCP to prescribe, for qualifying patients by embedded, remote, and remote student pharmacists. Secondary outcomes included the reasons for the non-implementation of statin recommendations, reasons statin therapy was not prescribed to patients contributing to the SUPD measure gap, and statin drug and dose prescribed for appropriateness. RESULTS: A total of 189 patients were included in the evaluation. In this study, 34.9% of the patients filled the prescribed or pended statin prescription and 83.3% of patients filled the prescribed or pended statin prescription at the recommended intensity according to the ACC/AHA guidelines, effectively closing the SUPD measure gap. The initiation rates of recommended statin prescriptions between the embedded pharmacist, remote pharmacist, and remote student pharmacist outreach were numerically different at 36.7%, 28.2%, and 36.7%, respectively, even though not statistically different (p=0.61). CONCLUSION: Remote student pharmacists' performance was equal to that of the embedded pharmacists when comparing the initiation rates of statin medications prescribed or pending the PCP's approval. The most common reason for non-implementation of statin therapy is that the statin was refused by the patient. Atorvastatin and rosuvastatin were the two most commonly prescribed statins.
RESUMEN
Growth factors are commonly added to cell culture media in cellular agriculture to mimic the endogenous process of proliferation and differentiation of cells. Many of these growth factors are endogenous to humans and known to be present in the edible tissues and milk of food animals. However, there is little or no information on the use of growth factors intentionally added in food production before the advent of cultivated meat. Ten commonly used growth factors have been reviewed to include information on their mode of action, bioavailability, occurrence in food and food animals, endogenous levels in humans, as well as exposure and toxicological information drawn from relevant animal studies and human clinical trials with a focus on oral exposure. In addition, a comparison of homology of growth factors was done to compare the sequence homology of growth factors from humans and domestic animal species commonly consumed as food, such as bovine, porcine, and poultry. This information has been gathered as the starting point to determine the safety of use of growth factors in cultivated meat meant for human consumption. The change in levels of growth factors measured in human milk and bovine milk after pasteurization and high-temperature treatment is discussed to give an indication of how commercial food processing can affect the levels of growth factors in food. The concept of substantial equivalence is also discussed together with a conservative exposure estimation. More work on how to integrate in silico assessments into the routine safety assessment of growth factors is needed.