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1.
Environ Sci Technol ; 58(26): 11492-11503, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38904357

RESUMEN

Soil organic carbon (SOC) plays a vital role in global carbon cycling and sequestration, underpinning the need for a comprehensive understanding of its distribution and controls. This study explores the importance of various covariates on SOC spatial distribution at both local (up to 1.25 km) and continental (USA) scales using a deep learning approach. Our findings highlight the significant role of terrain attributes in predicting SOC concentration distribution with terrain, contributing approximately one-third of the overall prediction at the local scale. At the continental scale, climate is only 1.2 times more important than terrain in predicting SOC distribution, whereas at the local scale, the structural pattern of terrain is 14 and 2 times more important than climate and vegetation, respectively. We underscore that terrain attributes, while being integral to the SOC distribution at all scales, are stronger predictors at the local scale with explicit spatial arrangement information. While this observational study does not assess causal mechanisms, our analysis nonetheless presents a nuanced perspective about SOC spatial distribution, which suggests disparate predictors of SOC at local and continental scales. The insights gained from this study have implications for improved SOC mapping, decision support tools, and land management strategies, aiding in the development of effective carbon sequestration initiatives and enhancing climate mitigation efforts.


Asunto(s)
Carbono , Clima , Suelo , Suelo/química , Ciclo del Carbono , Secuestro de Carbono
2.
Nat Immunol ; 12(8): 761-9, 2011 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-21706006

RESUMEN

The migration of neutrophils into inflamed tissues is a fundamental component of innate immunity. A decisive step in this process is the polarized migration of blood neutrophils through endothelial cells (ECs) lining the venular lumen (transendothelial migration (TEM)) in a luminal-to-abluminal direction. By real-time confocal imaging, we found that neutrophils had disrupted polarized TEM ('hesitant' and 'reverse') in vivo. We noted these events in inflammation after ischemia-reperfusion injury, characterized by lower expression of junctional adhesion molecule C (JAM-C) at EC junctions, and they were enhanced by blockade or genetic deletion of JAM-C in ECs. Our results identify JAM-C as a key regulator of polarized neutrophil TEM in vivo and suggest that reverse TEM of neutrophils can contribute to the dissemination of systemic inflammation.


Asunto(s)
Moléculas de Adhesión Celular/inmunología , Endotelio Vascular/inmunología , Inmunoglobulinas/inmunología , Inflamación/inmunología , Neutrófilos/inmunología , Migración Transendotelial y Transepitelial/inmunología , Animales , Endotelio Vascular/citología , Endotelio Vascular/patología , Procesamiento de Imagen Asistido por Computador , Inflamación/patología , Ratones , Microscopía Confocal , Daño por Reperfusión/inmunología , Daño por Reperfusión/patología
3.
FASEB J ; 36(1): e22065, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34847625

RESUMEN

Neutrophil trafficking is a key component of the inflammatory response. Here, we have investigated the role of the immunomodulatory lectin Galectin-9 (Gal-9) on neutrophil recruitment. Our data indicate that Gal-9 is upregulated in the inflamed vasculature of RA synovial biopsies and report the release of Gal-9 into the extracellular environment following endothelial cell activation. siRNA knockdown of endothelial Gal-9 resulted in reduced neutrophil adhesion and neutrophil recruitment was significantly reduced in Gal-9 knockout mice in a model of zymosan-induced peritonitis. We also provide evidence for Gal-9 binding sites on human neutrophils; Gal-9 binding induced neutrophil activation (increased expression of ß2 integrins and reduced expression of CD62L). Intra-vital microscopy confirmed a pro-recruitment role for Gal-9, with increased numbers of transmigrated neutrophils following Gal-9 administration. We studied the role of both soluble and immobilized Gal-9 on human neutrophil recruitment. Soluble Gal-9 significantly strengthened the interaction between neutrophils and the endothelium and inhibited neutrophil crawling on ICAM-1. When immobilized, Gal-9 functioned as an adhesion molecule and captured neutrophils from the flow. Neutrophils adherent to Gal-9 exhibited a spread/activated phenotype that was inhibited by CD18 and CD44 neutralizing antibodies, suggesting a role for these molecules in the pro-adhesive effects of Gal-9. Our data indicate that Gal-9 is expressed and released by the activated endothelium and functions both in soluble form and when immobilized as a neutrophil adhesion molecule. This study paves the way for further investigation of the role of Gal-9 in leukocyte recruitment in different inflammatory settings.


Asunto(s)
Antígenos CD18/metabolismo , Galectinas/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Receptores de Hialuranos/metabolismo , Neutrófilos/metabolismo , Migración Transendotelial y Transepitelial , Animales , Adhesión Celular , Humanos , Ratones
4.
Am J Med Genet A ; 191(11): 2728-2735, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37698238

RESUMEN

Grange syndrome (GRNG-MIM#135580) is a rare recessive disorder associating variable features including diffuse vascular stenosis, brachysyndactyly, osteopenia with increased bone fragility, cardiac malformations, and variable developmental delay. Since its first description in 1998, only 15 individuals from 10 families have been reported, carrying homozygous or compound heterozygous frameshift or nonsense variants in YY1AP1. In a patient with cutaneous and bone syndactyly and a hemorrhagic stroke at the age of 16 months, consistent with a clinical diagnosis of GRNG, we performed exome sequencing after negative array-CGH and congenital limb malformation panel results. Copy number variant analysis from exome data identified a homozygous intragenic out-of-frame deletion of 1.84 kb encompassing exons seven and eight of YY1AP1, confirming a molecular diagnosis of GRNG. Genetic counseling led to the identification of additional family members compatible with GRNG. Here, we provide new insights into the phenotypic variability associated with GRNG and highlight the utility of the detection of small copy number variants to identify the molecular causes of heterogeneous malformative genetic disorders.

5.
BMC Health Serv Res ; 23(1): 386, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085862

RESUMEN

BACKGROUND: With the development of next generation sequencing technologies in France, exome sequencing (ES) has recently emerged as an opportunity to improve the diagnosis rate of patients presenting an intellectual disability (ID). To help French policy makers determine an adequate tariff for ES, we aimed to assess the unit cost per ES diagnostic test for ID from the preparation of the pre-analytical step until the report writing step and to identify its main cost drivers. METHODS: A micro-costing bottom-up approach was conducted for the year 2018 in a French setting as part of the DISSEQ study, a cost-effectiveness study funded by the Ministry of Health and performed in collaboration with the GAD (Génétique des Anomalies du Développement), a genetic team from the Dijon University Hospital, and a public sequencing platform, the Centre National de Recherche en Génomique Humaine (CNRGH). The analysis was conducted from the point of view of these two ES stakeholders. All of the resources (labor, equipment, disposables and reagents, reusable material) required to analyze blood samples were identified, collected and valued. Several sensitivity analyses were performed. RESULTS: The unit nominal cost per ES diagnostic test for ID was estimated to be €2,019.39. Labor represented 50.7% of the total cost. The analytical step (from the preparation of libraries to the analysis of sequences) represented 88% of the total cost. Sensitivity analyses suggested that a simultaneous price decrease of 20% for the capture kit and 50% for the sequencing support kit led to an estimation of €1,769 per ES diagnostic test for ID. CONCLUSION: This is the first estimation of ES cost to be done in the French setting of ID diagnosis. The estimation is especially influenced by the price of equipment kits, but more generally by the organization of the centers involved in the different steps of the analysis and the time period in which the study was conducted. This information can now be used to define an adequate tariff and assess the efficiency of ES. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT03287206 on September 19, 2017.


Asunto(s)
Discapacidad Intelectual , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Exoma , Francia
6.
Opt Express ; 30(22): 40188-40195, 2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36298955

RESUMEN

Quantum cascade detectors (QCDs) are devices operating at zero external bias with a low dark-current. They show linear detection and high saturation intensities, making them suitable candidates for heterodyne detection in long-wave infrared (LWIR) free space optical communication systems. We present an approach to mitigate the performance limitation at long wavelengths, by a comparison of similar single and multi-period QCDs for optimizing their responsivity and noise behaviour. Our InGaAs/InAlAs/InP ridge QCDs are designed for operation at λ = 9.124 µm. Optical waveguide simulations support the accurate optical characterization. A detailed device analysis reveals room-temperature responsivities of 111 mA/W for the 15-period and 411 mA/W for the single-period device.

7.
J Cell Sci ; 132(5)2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30745334

RESUMEN

Mesenchymal stromal cells (MSCs) upregulate podoplanin at sites of infection, chronic inflammation and cancer. Here, we investigated the functional consequences of podoplanin expression on the migratory potential of MSCs and their interactions with circulating platelets. Expression of podoplanin significantly enhanced the migration of MSCs compared to MSCs lacking podoplanin. Rac-1 inhibition altered the membrane localisation of podoplanin and in turn significantly reduced MSC migration. Blocking Rac-1 activity had no effect on the migration of MSCs lacking podoplanin, indicating that it was responsible for regulation of migration through podoplanin. When podoplanin-expressing MSCs were seeded on the basal surface of a porous filter, they were able to capture platelets perfused over the uncoated apical surface and induce platelet aggregation. Similar microthrombi were observed when endothelial cells (ECs) were co-cultured on the apical surface. Confocal imaging shows podoplanin-expressing MSCs extending processes into the EC layer, and these processes could interact with circulating platelets. In both models, platelet aggregation induced by podoplanin-expressing MSCs was inhibited by treatment with recombinant soluble C-type lectin-like receptor 2 (CLEC-2; encoded by the gene Clec1b). Thus, podoplanin may enhance the migratory capacity of tissue-resident MSCs and enable novel interactions with cells expressing CLEC-2.


Asunto(s)
Plaquetas/fisiología , Endotelio Vascular/fisiología , Glicoproteínas de Membrana/metabolismo , Células Madre Mesenquimatosas/metabolismo , Trombosis/metabolismo , Movimiento Celular , Células Cultivadas , Endotelio Vascular/patología , Humanos , Lectinas Tipo C/metabolismo , Glicoproteínas de Membrana/genética , Microscopía Confocal , Comunicación Paracrina , Agregación Plaquetaria , ARN Interferente Pequeño/genética , Proteína de Unión al GTP rac1/metabolismo
8.
Haematologica ; 105(5): 1248-1261, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31467123

RESUMEN

Interactions between platelets, leukocytes and the vessel wall provide alternative pathological routes of thrombo-inflammatory leukocyte recruitment. We found that when platelets were activated by a range of agonists in whole blood, they shed platelet-derived extracellular vesicles which rapidly and preferentially bound to blood monocytes compared to other leukocytes. Platelet-derived extracellular vesicle binding to monocytes was initiated by P-selectin-dependent adhesion and was stabilised by binding of phosphatidylserine. These interactions resulted in the progressive transfer of the platelet adhesion receptor GPIbα to monocytes. GPIbα+-monocytes tethered and rolled on immobilised von Willebrand Factor or were recruited and activated on endothelial cells treated with TGF-ß1 to induce the expression of von Willebrand Factor. In both models monocyte adhesion was ablated by a function-blocking antibody against GPIbα. Monocytes could also bind platelet-derived extracellular vesicle in mouse blood in vitro and in vivo Intratracheal instillations of diesel nanoparticles, to model chronic pulmonary inflammation, induced accumulation of GPIbα on circulating monocytes. In intravital experiments, GPIbα+-monocytes adhered to the microcirculation of the TGF-ß1-stimulated cremaster muscle, while in the ApoE-/- model of atherosclerosis, GPIbα+-monocytes adhered to the carotid arteries. In trauma patients, monocytes bore platelet markers within 1 hour of injury, the levels of which correlated with severity of trauma and resulted in monocyte clearance from the circulation. Thus, we have defined a novel thrombo-inflammatory pathway in which platelet-derived extracellular vesicles transfer a platelet adhesion receptor to monocytes, allowing their recruitment in large and small blood vessels, and which is likely to be pathogenic.


Asunto(s)
Plaquetas , Vesículas Extracelulares , Animales , Células Endoteliales , Humanos , Inflamación , Ratones , Monocitos , Complejo GPIb-IX de Glicoproteína Plaquetaria
9.
Catheter Cardiovasc Interv ; 95(7): 1277-1284, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32105408

RESUMEN

AIMS: Peripheral arteries are constantly exposed to deformation (elongation, twisting, shortening, compression) making bioresorbable scaffolds (BRS) a potentially attractive therapeutic alternative to metallic stents. We conducted a long-term pilot preclinical study of a novel sirolimus-eluting BRS in peripheral arteries. METHODS AND RESULTS: Fourteen BRS were deployed in iliofemoral arteries of seven healthy Yucatan miniswine and examined with imaging, pharmacokinetic, histopathologic, and polymer degradation techniques at 0, 30, 90, 180 days, 1, 2, and 3.3 years. Angiographic late luminal loss remained unchanged at 30 and 180 days but significantly decreased from 1 to 3.3 years. optical coherence tomography (OCT) showed late increase in lumen area (1 year: 14.70 ± 3.58 mm2 , 2 years 22.04 ± 3.81 mm2 , and 3.3 years 23.45 ± 7.07 mm2 ; p < .05) primarily due to scaffold area enlargement between 1 and 3.3 years, while there was no difference in the percent area stenosis at all time points. Histologic evidence of scaffold degradation was observed starting at 2 years, with minimal inflammatory reaction. At 3.3 years, BRS struts were rarely discernible by OCT, confirmed by a nearly complete polymer degradation by molecular weight analysis. CONCLUSIONS: In this pilot study, novel sirolimus-eluting BRS showed promising acute and chronic performance in the iliofemoral arteries of Yucatan miniswine.


Asunto(s)
Implantes Absorbibles , Angioplastia de Balón/instrumentación , Fármacos Cardiovasculares/administración & dosificación , Arteria Femoral/efectos de los fármacos , Arteria Ilíaca/efectos de los fármacos , Sirolimus/administración & dosificación , Angioplastia de Balón/efectos adversos , Animales , Fármacos Cardiovasculares/farmacocinética , Diseño de Equipo , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/patología , Arteria Ilíaca/diagnóstico por imagen , Arteria Ilíaca/patología , Ensayo de Materiales , Modelos Animales , Proyectos Piloto , Sirolimus/farmacocinética , Porcinos , Porcinos Enanos , Factores de Tiempo
10.
Tob Control ; 29(3): 282-288, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31088915

RESUMEN

BACKGROUND: In the UK, a ban on the open display of tobacco products at the point of sale (POS) was phased in between 2012 and 2015. We explored any impact of the ban on youth before, during and after implementation. METHODS: A repeat cross-sectional in-home survey with young people aged 11-16 years old in the UK was conducted preban (2011, n=1373), mid-ban (2014, n=1205) and postban (2016, n=1213). The analysis focuses on the never-smokers in the sample (n=2953 in total). Preban, we quantified the associations of noticing cigarettes displayed at POS and cigarette brand awareness with smoking susceptibility. We measured any change in noticing cigarettes displayed at POS, cigarette brand awareness and smoking susceptibility between preban, mid-ban and postban. Postban, we assessed support for a display ban, perceived appeal of cigarettes and perceived acceptability of smoking as a result of closed displays. RESULTS: Preban, noticing cigarettes displayed at POS (adjusted OR [AOR]=1.97, 95% CI 1.30 to 2.98) and higher brand awareness (AOR=1.15, 95% CI 1.03 to 1.29) were positively associated with smoking susceptibility. The mean number of brands recalled declined from 0.97 preban to 0.69 postban (p<0.001). Smoking susceptibility decreased from 28% preban to 23% mid-ban and 18% postban (p for trend <0.001). Postban, 90% of never-smokers supported the display ban and indicated that it made cigarettes seem unappealing (77%) and made smoking seem unacceptable (87%). CONCLUSIONS: Both partial and full implementation of a display ban were followed by a reduction in smoking susceptibility among adolescents, which may be driven by decreases in brand awareness.


Asunto(s)
Conducta del Adolescente , Conducta Infantil , Fumar Cigarrillos , Comercio/legislación & jurisprudencia , Mercadotecnía/legislación & jurisprudencia , Industria del Tabaco/legislación & jurisprudencia , Productos de Tabaco/legislación & jurisprudencia , Adolescente , Niño , Femenino , Conductas Relacionadas con la Salud , Política de Salud , Promoción de la Salud , Estado de Salud , Humanos , Legislación de Medicamentos , Masculino , Oportunidad Relativa , Industria del Tabaco/economía , Productos de Tabaco/economía , Reino Unido
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