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1.
Cell ; 170(5): 845-859.e19, 2017 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-28823557

RESUMEN

The lateral ventricle subventricular zone (SVZ) is a frequent and consequential site of pediatric and adult glioma spread, but the cellular and molecular mechanisms mediating this are poorly understood. We demonstrate that neural precursor cell (NPC):glioma cell communication underpins this propensity of glioma to colonize the SVZ through secretion of chemoattractant signals toward which glioma cells home. Biochemical, proteomic, and functional analyses of SVZ NPC-secreted factors revealed the neurite outgrowth-promoting factor pleiotrophin, along with required binding partners SPARC/SPARCL1 and HSP90B, as key mediators of this chemoattractant effect. Pleiotrophin expression is strongly enriched in the SVZ, and pleiotrophin knock down starkly reduced glioma invasion of the SVZ in the murine brain. Pleiotrophin, in complex with the binding partners, activated glioma Rho/ROCK signaling, and ROCK inhibition decreased invasion toward SVZ NPC-secreted factors. These findings demonstrate a pathogenic role for NPC:glioma interactions and potential therapeutic targets to limit glioma invasion. PAPERCLIP.


Asunto(s)
Neoplasias Encefálicas/patología , Proteínas Portadoras/metabolismo , Citocinas/metabolismo , Glioma/patología , Ventrículos Laterales/patología , Invasividad Neoplásica/patología , Anciano , Animales , Neoplasias Encefálicas/metabolismo , Comunicación Celular , Niño , Sistemas de Liberación de Medicamentos , Femenino , Glioma/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Xenoinjertos , Humanos , Ventrículos Laterales/metabolismo , Masculino , Ratones , Trasplante de Neoplasias , Transducción de Señal , Proteínas de Unión al GTP rho/metabolismo
2.
Cell ; 155(1): 242-56, 2013 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-24074872

RESUMEN

The complex network of specialized cells and molecules in the immune system has evolved to defend against pathogens, but inadvertent immune system attacks on "self" result in autoimmune disease. Both genetic regulation of immune cell levels and their relationships with autoimmunity are largely undetermined. Here, we report genetic contributions to quantitative levels of 95 cell types encompassing 272 immune traits, in a cohort of 1,629 individuals from four clustered Sardinian villages. We first estimated trait heritability, showing that it can be substantial, accounting for up to 87% of the variance (mean 41%). Next, by assessing ∼8.2 million variants that we identified and confirmed in an extended set of 2,870 individuals, 23 independent variants at 13 loci associated with at least one trait. Notably, variants at three loci (HLA, IL2RA, and SH2B3/ATXN2) overlap with known autoimmune disease associations. These results connect specific cellular phenotypes to specific genetic variants, helping to explicate their involvement in disease.


Asunto(s)
Citometría de Flujo/métodos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Enfermedades del Sistema Inmune/genética , Polimorfismo de Nucleótido Simple , Humanos , Fenotipo
3.
EMBO J ; 40(14): e106317, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-34003511

RESUMEN

Fibrodysplasia ossificans progressiva (FOP) and diffuse intrinsic pontine glioma (DIPG) are debilitating diseases that share causal mutations in ACVR1, a TGF-ß family type I receptor. ACVR1R206H is a frequent mutation in both diseases. Pathogenic signaling via the SMAD1/5 pathway is mediated by Activin A, but how the mutation triggers aberrant signaling is not known. We show that ACVR1 is essential for Activin A-mediated SMAD1/5 phosphorylation and is activated by two distinct mechanisms. Wild-type ACVR1 is activated by the Activin type I receptors, ACVR1B/C. In contrast, ACVR1R206H activation does not require upstream kinases, but is predominantly activated via Activin A-dependent receptor clustering, which induces its auto-activation. We use optogenetics and live-imaging approaches to demonstrate Activin A-induced receptor clustering and show it requires the type II receptors ACVR2A/B. Our data provide molecular mechanistic insight into the pathogenesis of FOP and DIPG by linking the causal activating genetic mutation to disrupted signaling.


Asunto(s)
Receptores de Activinas Tipo I/genética , Receptores de Activinas Tipo I/metabolismo , Activinas/genética , Activinas/metabolismo , Fosforilación/genética , Animales , Línea Celular , Análisis por Conglomerados , Células HEK293 , Humanos , Ratones , Mutación/genética , Miositis Osificante/genética , Células 3T3 NIH , Transducción de Señal/genética
4.
N Engl J Med ; 386(26): 2471-2481, 2022 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-35767439

RESUMEN

BACKGROUND: Pediatric patients with diffuse intrinsic pontine glioma (DIPG) have a poor prognosis, with a median survival of less than 1 year. Oncolytic viral therapy has been evaluated in patients with pediatric gliomas elsewhere in the brain, but data regarding oncolytic viral therapy in patients with DIPG are lacking. METHODS: We conducted a single-center, dose-escalation study of DNX-2401, an oncolytic adenovirus that selectively replicates in tumor cells, in patients with newly diagnosed DIPG. The patients received a single virus infusion through a catheter placed in the cerebellar peduncle, followed by radiotherapy. The primary objective was to assess the safety and adverse-event profile of DNX-2401. The secondary objectives were to evaluate the effect of DNX-2401 on overall survival and quality of life, to determine the percentage of patients who have an objective response, and to collect tumor-biopsy and peripheral-blood samples for correlative studies of the molecular features of DIPG and antitumor immune responses. RESULTS: A total of 12 patients, 3 to 18 years of age, with newly diagnosed DIPG received 1×1010 (the first 4 patients) or 5×1010 (the subsequent 8 patients) viral particles of DNX-2401, and 11 received subsequent radiotherapy. Adverse events among the patients included headache, nausea, vomiting, and fatigue. Hemiparesis and tetraparesis developed in 1 patient each. Over a median follow-up of 17.8 months (range, 5.9 to 33.5), a reduction in tumor size, as assessed on magnetic resonance imaging, was reported in 9 patients, a partial response in 3 patients, and stable disease in 8 patients. The median survival was 17.8 months. Two patients were alive at the time of preparation of the current report, 1 of whom was free of tumor progression at 38 months. Examination of a tumor sample obtained during autopsy from 1 patient and peripheral-blood studies revealed alteration of the tumor microenvironment and T-cell repertoire. CONCLUSIONS: Intratumoral infusion of oncolytic virus DNX-2401 followed by radiotherapy in pediatric patients with DIPG resulted in changes in T-cell activity and a reduction in or stabilization of tumor size in some patients but was associated with adverse events. (Funded by the European Research Council under the European Union's Horizon 2020 Research and Innovation Program and others; EudraCT number, 2016-001577-33; ClinicalTrials.gov number, NCT03178032.).


Asunto(s)
Neoplasias del Tronco Encefálico , Glioma Pontino Intrínseco Difuso , Viroterapia Oncolítica , Virus Oncolíticos , Adenoviridae , Adolescente , Astrocitoma/radioterapia , Astrocitoma/terapia , Neoplasias del Tronco Encefálico/mortalidad , Neoplasias del Tronco Encefálico/patología , Neoplasias del Tronco Encefálico/radioterapia , Neoplasias del Tronco Encefálico/terapia , Niño , Preescolar , Glioma Pontino Intrínseco Difuso/mortalidad , Glioma Pontino Intrínseco Difuso/radioterapia , Glioma Pontino Intrínseco Difuso/terapia , Glioma/radioterapia , Glioma/terapia , Humanos , Infusiones Intralesiones , Viroterapia Oncolítica/efectos adversos , Viroterapia Oncolítica/métodos , Calidad de Vida , Microambiente Tumoral
5.
FASEB J ; 38(4): e23468, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38334433

RESUMEN

The endothelial regulation of platelet activity is incompletely understood. Here we describe novel approaches to find molecular pathways implicated on the platelet-endothelium interaction. Using high-shear whole-blood microfluidics, employing coagulant or non-coagulant conditions at physiological temperature, we observed that the presence of human umbilical vein endothelial cells (HUVEC) strongly suppressed platelet adhesion and activation, via the collagen receptor glycoprotein VI (GPVI) and the PAR receptors for thrombin. Real-time monitoring of the cytosolic Ca2+ rises in the platelets indicated no major improvement of inhibition by prostacyclin or nitric oxide. Similarly under stasis, exposure of isolated platelets to HUVEC reduced the Ca2+ responses by collagen-related peptide (CRP-XL, GPVI agonist) and thrombin (PAR agonist). We then analyzed the label-free phosphoproteome of platelets (three donors), exposed to HUVEC, CRP-XL, and/or thrombin. High-resolution mass spectrometry gave 5463 phosphopeptides, corresponding to 1472 proteins, with good correlation between biological and technical replicates (R > .86). Stringent filtering steps revealed 26 regulatory pathways (Reactome) and 143 regulated kinase substrates (PhosphoSitePlus), giving a set of protein phosphorylation sites that was differentially (44) or similarly (110) regulated by HUVEC or agonist exposure. The differential regulation was confirmed by stable-isotope analysis of platelets from two additional donors. Substrate analysis indicated major roles of poorly studied protein kinase classes (MAPK, CDK, DYRK, STK, PKC members). Collectively, these results reveal a resetting of the protein phosphorylation profile in platelets exposed to endothelium or to conventional agonists and to endothelium-promoted activity of a multi-kinase network, beyond classical prostacyclin and nitric oxide actors, that may contribute to platelet inhibition.


Asunto(s)
Glicoproteínas de Membrana Plaquetaria , Trombina , Humanos , Glicoproteínas de Membrana Plaquetaria/metabolismo , Trombina/metabolismo , Proteínas Quinasas/metabolismo , Óxido Nítrico/metabolismo , Células Endoteliales/metabolismo , Activación Plaquetaria/fisiología , Plaquetas/metabolismo , Endotelio/metabolismo , Prostaglandinas I
6.
Theor Appl Genet ; 137(10): 244, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39354106

RESUMEN

Pearl millet is an essential crop worldwide, with noteworthy resilience to abiotic stress, yet the advancement of its breeding remains constrained by the underutilization of molecular-assisted breeding techniques. In this study, we collected 1,455,924 single nucleotide polymorphism (SNP) and 124,532 structural variant (SV) markers primarily from a pearl millet inbred germplasm association panel consisting of 242 accessions including 120 observed phenotypes, mostly related to the yield. Our findings revealed that the SV markers had the capacity to capture genetic diversity not discerned by SNP markers. Furthermore, no correlation in heritability was observed between SNP and SV markers associated with the same phenotype. The assessment of the nine genomic prediction models revealed that SV markers performed better than SNP markers. When using the SV markers as the predictor variable, the genomic BLUP model achieved the best performance, while using the SNP markers, Bayesian methods outperformed the others. The integration of these models enabled the identification of eight candidate accessions with high genomic estimated breeding values (GEBV) across nine phenotypes using SNP markers. Four candidate accessions were identified with high GEBV across 22 phenotypes using SV markers. Notably, accession 'P23' emerged as a consistent candidate predicted based on both SNP and SV markers specifically for panicle number. These findings contribute valuable insights into the potential of utilizing both SNP and SV markers for genomic prediction in pearl millet breeding. Moreover, the identification of promising candidate accessions, such as 'P23', underscores the accelerated prospects of molecular breeding initiatives for enhancing pearl millet varieties.


Asunto(s)
Genoma de Planta , Pennisetum , Fenotipo , Fitomejoramiento , Polimorfismo de Nucleótido Simple , Pennisetum/genética , Pennisetum/crecimiento & desarrollo , Marcadores Genéticos , Selección Genética , Teorema de Bayes , Genómica/métodos , Genotipo
7.
Curr Gastroenterol Rep ; 26(6): 166-171, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38558135

RESUMEN

PURPOSE OF REVIEW: This review evaluates the current literature on ileus, impaired gastrointestinal transit (IGT), and acute gastrointestinal injury (AGI) and its impact on multiple organ dysfunction syndrome. RECENT FINDINGS: Ileus is often under recognized in critically ill patients and is associated with significant morbidity and is potentially a marker of disease severity as seen in other organs like kidneys (ATN).


Asunto(s)
Enfermedad Crítica , Ileus , Insuficiencia Multiorgánica , Humanos , Insuficiencia Multiorgánica/etiología , Insuficiencia Multiorgánica/fisiopatología , Insuficiencia Multiorgánica/diagnóstico , Ileus/etiología , Ileus/fisiopatología , Ileus/diagnóstico , Tránsito Gastrointestinal/fisiología
8.
Nature ; 624(7990): 46-48, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37993618
10.
Sensors (Basel) ; 24(18)2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39338614

RESUMEN

The microfluidic measurement of capillary flow can be used to evaluate the response of biological samples to stimulation, where distance and velocity are altered. Melt-extruded multi-bored microfluidic capillaries allow for high-throughput testing with low device cost, but simple devices may limit control over sample flow when compared to the more complex "lab-on-a-chip" devices produced using advanced microfluidic fabrication methods. Previously, we measured the dynamics of global haemostasis stimulated by thrombin by dipping straight vertical microcapillaries into blood, but only the most rapid response could be monitored, as flow slowed significantly within 30 s. Here, we show an innovative method to extend both the stimulation process and flow measurement time without increasing the cost of the device by adding simple loops to the flexible extruded device. The loops enable longer time-scale measurements by increasing resistance to flow, thereby reducing the dependence on high stimulus concentrations for rapid reactions. The instantaneous velocity and equilibrium heights of straight and looped vertical microcapillary films were assessed with water, plasma and whole blood, showing that the loops create additional frictional resistances, reduce flow velocity and prolong residence times for increased time scales of the stimulation process. A modified pressure balance model was used to capture flow dynamics with the added loop. Looped devices loaded with thrombin and collagen showed an improved detection of blood stimulation responses even with lower stimulus concentrations, compared to straight vertical capillaries. Thrombin-activated blood samples in straight capillaries provided a maximum measurement zone of only 4 mm, while the looped design significantly increased this to 11 mm for much longer time scale measurements. Our results suggest that extending stimulation times can be achieved without complex microfluidic fabrication methods, potentially improving concentration-response blood stimulation assays, and may enhance the accuracy and reliability. We conclude adding a loop to low-cost extruded microfluidic devices may bring microfluidic devices closer to delivering on their promise of widespread, decentralized low-cost evaluation of blood response to stimulation in both research and clinical settings.


Asunto(s)
Dispositivos Laboratorio en un Chip , Trombina , Humanos , Técnicas Analíticas Microfluídicas/instrumentación , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/métodos , Microfluídica/instrumentación
11.
J Integr Plant Biol ; 66(4): 683-699, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38358036

RESUMEN

Drought is a major threat to alfalfa (Medicago sativa L.) production. The discovery of important alfalfa genes regulating drought response will facilitate breeding for drought-resistant alfalfa cultivars. Here, we report a genome-wide association study of drought resistance in alfalfa. We identified and functionally characterized an MYB-like transcription factor gene (MsMYBH), which increases the drought resistance in alfalfa. Compared with the wild-types, the biomass and forage quality were enhanced in MsMYBH overexpressed plants. Combined RNA-seq, proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1, MsMCP2, MsPRX1A and MsCARCAB to improve their expression. The outcomes of such interactions include better water balance, high photosynthetic efficiency and scavenge excess H2O2 in response to drought. Furthermore, an E3 ubiquitin ligase (MsWAV3) was found to induce MsMYBH degradation under long-term drought, via the 26S proteasome pathway. Furthermore, variable-number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms, and the variation is associated with promoter activity. Collectively, our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought-resistant alfalfa. This discovery also offers new insights into the mechanisms of drought resistance in alfalfa.


Asunto(s)
Resistencia a la Sequía , Plantones , Plantones/genética , Medicago sativa/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Estudio de Asociación del Genoma Completo , Peróxido de Hidrógeno/metabolismo , Fitomejoramiento , Sequías
12.
Plant Biotechnol J ; 21(11): 2348-2357, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37530223

RESUMEN

Millets are a class of nutrient-rich coarse cereals with high resistance to abiotic stress; thus, they guarantee food security for people living in areas with extreme climatic conditions and provide stress-related genetic resources for other crops. However, no platform is available to provide a comprehensive and systematic multi-omics analysis for millets, which seriously hinders the mining of stress-related genes and the molecular breeding of millets. Here, a free, web-accessible, user-friendly millets multi-omics database platform (Milletdb, http://milletdb.novogene.com) has been developed. The Milletdb contains six millets and their one related species genomes, graph-based pan-genomics of pearl millet, and stress-related multi-omics data, which enable Milletdb to be the most complete millets multi-omics database available. We stored GWAS (genome-wide association study) results of 20 yield-related trait data obtained under three environmental conditions [field (no stress), early drought and late drought] for 2 years in the database, allowing users to identify stress-related genes that support yield improvement. Milletdb can simplify the functional genomics analysis of millets by providing users with 20 different tools (e.g., 'Gene mapping', 'Co-expression', 'KEGG/GO Enrichment' analysis, etc.). On the Milletdb platform, a gene PMA1G03779.1 was identified through 'GWAS', which has the potential to modulate yield and respond to different environmental stresses. Using the tools provided by Milletdb, we found that the stress-related PLATZs TFs (transcription factors) family expands in 87.5% of millet accessions and contributes to vegetative growth and abiotic stress responses. Milletdb can effectively serve researchers in the mining of key genes, genome editing and molecular breeding of millets.


Asunto(s)
Barajamiento de ADN , Mijos , Humanos , Mijos/genética , Estudio de Asociación del Genoma Completo , Multiómica , Genómica/métodos
13.
Blood ; 137(6): 830-843, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-32822477

RESUMEN

Connexins oligomerise to form hexameric hemichannels in the plasma membrane that can further dock together on adjacent cells to form gap junctions and facilitate intercellular trafficking of molecules. In this study, we report the expression and function of an orphan connexin, connexin-62 (Cx62), in human and mouse (Cx57, mouse homolog) platelets. A novel mimetic peptide (62Gap27) was developed to target the second extracellular loop of Cx62, and 3-dimensional structural models predicted its interference with gap junction and hemichannel function. The ability of 62Gap27 to regulate both gap junction and hemichannel-mediated intercellular communication was observed using fluorescence recovery after photobleaching analysis and flow cytometry. Cx62 inhibition by 62Gap27 suppressed a range of agonist-stimulated platelet functions and impaired thrombosis and hemostasis. This was associated with elevated protein kinase A-dependent signaling in a cyclic adenosine monophosphate-independent manner and was not observed in Cx57-deficient mouse platelets (in which the selectivity of 62Gap27 for this connexin was also confirmed). Notably, Cx62 hemichannels were observed to function independently of Cx37 and Cx40 hemichannels. Together, our data reveal a fundamental role for a hitherto uncharacterized connexin in regulating the function of circulating cells.


Asunto(s)
Plaquetas/metabolismo , Conexinas/fisiología , Animales , Comunicación Celular/fisiología , Línea Celular , Conexinas/sangre , Conexinas/química , Conexinas/deficiencia , Conexinas/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Uniones Comunicantes/fisiología , Hemostasis/fisiología , Humanos , Integrinas/sangre , Megacariocitos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Modelos Moleculares , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/síntesis química , Fragmentos de Péptidos/farmacología , Adhesividad Plaquetaria , Agregación Plaquetaria , Conformación Proteica , Multimerización de Proteína , Relación Estructura-Actividad , Trombosis/sangre
14.
Phytopathology ; 113(8): 1506-1514, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36989124

RESUMEN

Samples from potato fields with lesions with late blight-like symptoms were collected from eastern North Carolina in 2017 and the causal agent was identified as Phytophthora nicotianae. We have identified P. nicotianae in potato and tomato samples from North Carolina, Virginia, Maryland, Pennsylvania, and New York. Ninety-two field samples were collected from 46 fields and characterized for mefenoxam sensitivity, mating type, and simple sequence repeat genotype using microsatellites. Thirty-two percent of the isolates were the A1 mating type, while 53% were the A2 mating type. In six cases, both A1 and A2 mating types were detected in the same field in the same year. All isolates tested were sensitive to mefenoxam. Two genetic groups were discerned based on STRUCTURE analysis: one included samples from North Carolina and Maryland, and one included samples from all five states. The data suggest two different sources of inoculum from the field sites sampled. Multiple haplotypes within a field and the detection of both mating types in close proximity suggests that P. nicotianae may be reproducing sexually in North Carolina. There was a decrease in the average number of days with weather suitable for late blight, from 2012 to 2016 and 2017 to 2021 in all of the North Carolina counties where P. nicotianae was reported. P. nicotianae is more thermotolerant than P. infestans and grows at higher temperatures (25 to 35°C) than P. infestans (18 to 22°C). Late blight outbreaks have decreased in recent years and first reports of disease are later, suggesting that the thermotolerant P. nicotianae may cause more disease as temperatures rise due to climate change.

15.
Sensors (Basel) ; 23(16)2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37631606

RESUMEN

BACKGROUND: Head impacts in sports can produce brain injuries. The accurate quantification of head kinematics through instrumented mouthguards (iMG) can help identify underlying brain motion during injurious impacts. The aim of the current study is to assess the validity of an iMG across a large range of linear and rotational accelerations to allow for on-field head impact monitoring. METHODS: Drop tests of an instrumented helmeted anthropometric testing device (ATD) were performed across a range of impact magnitudes and locations, with iMG measures collected concurrently. ATD and iMG kinematics were also fed forward to high-fidelity brain models to predict maximal principal strain. RESULTS: The impacts produced a wide range of head kinematics (16-171 g, 1330-10,164 rad/s2 and 11.3-41.5 rad/s) and durations (6-18 ms), representing impacts in rugby and boxing. Comparison of the peak values across ATD and iMG indicated high levels of agreement, with a total concordance correlation coefficient of 0.97 for peak impact kinematics and 0.97 for predicted brain strain. We also found good agreement between iMG and ATD measured time-series kinematic data, with the highest normalized root mean squared error for rotational velocity (5.47 ± 2.61%) and the lowest for rotational acceleration (1.24 ± 0.86%). Our results confirm that the iMG can reliably measure laboratory-based head kinematics under a large range of accelerations and is suitable for future on-field validity assessments.


Asunto(s)
Boxeo , Deportes , Fenómenos Biomecánicos , Aceleración , Movimiento (Física)
16.
Int J Mol Sci ; 24(17)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37686158

RESUMEN

Proteoglycans form a heterogeneous family of proteins with covalently bound sulfated glycosaminoglycans. The extracellular matrix proteoglycan perlecan has been proposed to bind to the platelet- and megakaryocyte-specific receptor G6bB, co-regulating platelet glycoprotein VI (GPVI) signaling. The derived non-sulfate proteoglycan endorepellin was previously shown to enhance platelet adhesion via the collagen receptor, integrin α2ß1. Here, we compared the roles of perlecan and other matrix proteoglycans in platelet responses and thrombus formation. We used multi-color flow cytometry to measure the degranulation and integrin αIIbß3 activation of washed platelets in response to various proteoglycans and collagen-related peptide (CRP), the GPVI agonist. Perlecan, but not endorepellin, enhanced the CRP-induced activation of platelets in a time- and concentration-dependent manner. Similar to collagen, immobilized perlecan, but not other proteoglycans, supported static platelet adhesion and spreading. In-flowed whole-blood perlecan diminished shear-dependent platelet adhesion, while it enforced GPVI-dependent thrombus formation-to a larger extent than endorepellin-to induce more contracted aggregates of activated platelets. We concluded that the sulfated proteoglycan perlecan enhances GPVI-dependent platelet responses extending to thrombus formation, but it does so at the expense of reduced adhesion of platelets under flow.


Asunto(s)
Proteoglicanos de Heparán Sulfato , Trombosis , Humanos , Proteínas de la Matriz Extracelular , Adhesividad Plaquetaria
17.
Radiology ; 304(1): 174-182, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35412366

RESUMEN

Background Diffuse midline gliomas (DMG) are characterized by a high incidence of H3 K27 mutations and poorer outcome. The HERBY trial has provided one of the largest cohorts of pediatric DMGs with available radiologic, histologic-genotypic, and survival data. Purpose To define MRI and molecular characteristics of DMG. Materials and Methods This study is a secondary analysis of a prospective trial (HERBY; ClinicalTrials.gov identifier, NCT01390948) undertaken between October 2011 and February 2016. Among 121 HERBY participants, 50 had midline nonpontine-based tumors. Midline high-grade gliomas were reclassified into DMG H3 K27 mutant, H3 wild type with enhancer of zest homologs inhibitory protein overexpression, epidermal growth factor receptormutant, or not otherwise stated. The epicenter of each tumor and other radiologic characteristics were ascertained from MRI and correlated with the new subtype classification, histopathologic characteristics, surgical extent, and outcome parameters. Kaplan-Meier curves and log-rank tests were applied to determine and describe survival differences between groups. Results There were 42 participants (mean age, 12 years ± 4 [SD]; 23 girls) with radiologically evaluable thalamic-based DMG. Eighteen had partial thalamic involvement (12 thalamopulvinar, six anteromedial), 10 involved a whole thalamus, nine had unithalamic tumors with diffuse contiguous extension, and five had bithalamic tumors (two symmetric, three partial). Twenty-eight participants had DMG H3 K27 mutant tumors; there were no differences in outcome compared with other DMGs (n = 4). Participants who underwent major debulking or total or near-total resection had longer overall survival (OS): 18.5 months vs 11.4 months (P = .02). Enrolled participants who developed leptomeningeal metastatic dissemination before starting treatment had worse outcomes (event-free survival, 2.9 months vs 8.0 months [P = .02]; OS, 11.4 months vs 18.5 months [P = .004]). Conclusion Thalamic involvement of diffuse midline gliomas ranged from localized partial thalamic to holo- or bithalamic with diffuse contiguous spread and had poor outcomes, irrespective of H3 K27 subtype alterations. Leptomeningeal dissemination and less than 50% surgical resection were adverse risk factors for survival. Clinical trial registration no. NCT01390948 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Widjaja in this issue.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Niño , Femenino , Glioma/diagnóstico por imagen , Glioma/genética , Glioma/patología , Histonas/genética , Humanos , Imagen por Resonancia Magnética , Mutación/genética , Estudios Prospectivos , Tálamo/patología
18.
Plant Biotechnol J ; 20(3): 592-609, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34717292

RESUMEN

Melilotus species are used as green manure and rotation crops worldwide and contain abundant pharmacologically active coumarins. However, there is a paucity of information on its genome and coumarin production and function. Here, we reported a chromosome-scale assembly of Melilotus albus genome with 1.04 Gb in eight chromosomes, containing 71.42% repetitive elements. Long terminal repeat retrotransposon bursts coincided with declining of population sizes during the Quaternary glaciation. Resequencing of 94 accessions enabled insights into genetic diversity, population structure, and introgression. Melilotus officinalis had relatively larger genetic diversity than that of M. albus. The introgression existed between M. officinalis group and M. albus group, and gene flows was from M. albus to M. officinalis. Selection sweep analysis identified candidate genes associated with flower colour and coumarin biosynthesis. Combining genomics, BSA, transcriptomics, metabolomics, and biochemistry, we identified a ß-glucosidase (BGLU) gene cluster contributing to coumarin biosynthesis. MaBGLU1 function was verified by overexpression in M. albus, heterologous expression in Escherichia coli, and substrate feeding, revealing its role in scopoletin (coumarin derivative) production and showing that nonsynonymous variation drives BGLU enzyme activity divergence in Melilotus. Our work will accelerate the understanding of biologically active coumarins and their biosynthetic pathways, and contribute to genomics-enabled Melilotus breeding.


Asunto(s)
Cumarinas , Melilotus , Cumarinas/metabolismo , Melilotus/química , Melilotus/genética , Melilotus/metabolismo , Fitomejoramiento , Biología de Sistemas , Transcriptoma/genética
19.
Brain ; 144(1): 53-69, 2021 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-33300045

RESUMEN

Paediatric high-grade gliomas (HGGs) account for the most brain tumour-related deaths in children and have a median survival of 12-15 months. One promising avenue of research is the development of novel therapies targeting the properties of non-neoplastic cell-types within the tumour such as tumour associated macrophages (TAMs). TAMs are immunosuppressive and promote tumour malignancy in adult HGG; however, in paediatric medulloblastoma, TAMs exhibit anti-tumour properties. Much is known about TAMs in adult HGG, yet little is known about them in the paediatric setting. This raises the question of whether paediatric HGGs possess a distinct constituency of TAMs because of their unique genetic landscapes. Using human paediatric HGG tissue samples and murine models of paediatric HGG, we demonstrate diffuse midline gliomas possess a greater inflammatory gene expression profile compared to hemispheric paediatric HGGs. We also show despite possessing sparse T-cell infiltration, human paediatric HGGs possess high infiltration of IBA1+ TAMs. CD31, PDGFRß, and PDGFB all strongly correlate with IBA1+ TAM infiltration. To investigate the TAM population, we used the RCAS/tv-a system to recapitulate paediatric HGG in newborn immunocompetent mice. Tumours are induced in Nestin-positive brain cells by PDGFA or PDGFB overexpression with Cdkn2a or Tp53 co-mutations. Tumours driven by PDGFB have a significantly lower median survival compared to PDGFA-driven tumours and have increased TAM infiltration. NanoString and quantitative PCR analysis indicates PDGFB-driven tumours have a highly inflammatory microenvironment characterized by high chemokine expression. In vitro bone marrow-derived monocyte and microglial cultures demonstrate bone marrow-derived monocytes are most responsible for the production of inflammatory signals in the tumour microenvironment in response to PDGFB stimulation. Lastly, using knockout mice deficient for individual chemokines, we demonstrate the feasibility of reducing TAM infiltration and prolonging survival in both PDGFA and PDGFB-driven tumours. We identify CCL3 as a potential key chemokine in these processes in both humans and mice. Together, these studies provide evidence for the potent inflammatory effects PDGFB has in paediatric HGGs.


Asunto(s)
Neoplasias Encefálicas/inmunología , Encefalitis/inmunología , Proteínas Proto-Oncogénicas c-sis/inmunología , Macrófagos Asociados a Tumores/inmunología , Adolescente , Adulto , Animales , Neoplasias Encefálicas/genética , Células Cultivadas , Quimiocinas/genética , Niño , Preescolar , Encefalitis/genética , Femenino , Glioma , Humanos , Lactante , Recién Nacido , Masculino , Ratones Endogámicos C57BL , Transcriptoma , Adulto Joven
20.
Sensors (Basel) ; 22(10)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35632119

RESUMEN

Achieving global goals for sustainable nutrition, health, and wellbeing will depend on delivering enhanced diets to humankind. This will require instantaneous access to information on food-source quality at key points of agri-food systems. Although laboratory analysis and benchtop NIR spectrometers are regularly used to quantify grain quality, these do not suit all end users, for example, stakeholders in decentralized agri-food chains that are typical in emerging economies. Therefore, we explored benchtop and portable NIR instruments, and the methods that might aid these particular end uses. For this purpose, we generated NIR spectra for 328 grain samples from multiple cereals (finger millet, foxtail millet, maize, pearl millet, and sorghum) with a standard benchtop NIR spectrometer (DS2500, FOSS) and a novel portable NIR-based instrument (HL-EVT5, Hone). We explored classical deterministic methods (via winISI, FOSS), novel machine learning (ML)-driven methods (via Hone Create, Hone), and a convolutional neural network (CNN)-based method for building the calibrations to predict grain protein out of the NIR spectra. All of the tested methods enabled us to build relevant calibrations out of both types of spectra (i.e., R2 ≥ 0.90, RMSE ≤ 0.91, RPD ≥ 3.08). Generally, the calibration methods integrating the ML techniques tended to enhance the prediction capacity of the model. We also documented that the prediction of grain protein content based on the NIR spectra generated using the novel portable instrument (HL-EVT5, Hone) was highly relevant for quantitative protein predictions (R2 = 0.91, RMSE = 0.97, RPD = 3.48). Thus, the presented findings lay the foundations for the expanded use of NIR spectroscopy in agricultural research, development, and trade.


Asunto(s)
Proteínas de Granos , Agricultura , Calibración , Grano Comestible , Espectroscopía Infrarroja Corta/métodos
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