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1.
Acta Neuropathol Commun ; 11(1): 6, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36631900

RESUMEN

The most common malignant brain tumour in children, medulloblastoma (MB), is subdivided into four clinically relevant molecular subgroups, although targeted therapy options informed by understanding of different cellular features are lacking. Here, by comparing the most aggressive subgroup (Group 3) with the intermediate (SHH) subgroup, we identify crucial differences in tumour heterogeneity, including unique metabolism-driven subpopulations in Group 3 and matrix-producing subpopulations in SHH. To analyse tumour heterogeneity, we profiled individual tumour nodules at the cellular level in 3D MB hydrogel models, which recapitulate subgroup specific phenotypes, by single cell RNA sequencing (scRNAseq) and 3D OrbiTrap Secondary Ion Mass Spectrometry (3D OrbiSIMS) imaging. In addition to identifying known metabolites characteristic of MB, we observed intra- and internodular heterogeneity and identified subgroup-specific tumour subpopulations. We showed that extracellular matrix factors and adhesion pathways defined unique SHH subpopulations, and made up a distinct shell-like structure of sulphur-containing species, comprising a combination of small leucine-rich proteoglycans (SLRPs) including the collagen organiser lumican. In contrast, the Group 3 tumour model was characterized by multiple subpopulations with greatly enhanced oxidative phosphorylation and tricarboxylic acid (TCA) cycle activity. Extensive TCA cycle metabolite measurements revealed very high levels of succinate and fumarate with malate levels almost undetectable particularly in Group 3 tumour models. In patients, high fumarate levels (NMR spectroscopy) alongside activated stress response pathways and high Nuclear Factor Erythroid 2-Related Factor 2 (NRF2; gene expression analyses) were associated with poorer survival. Based on these findings we predicted and confirmed that NRF2 inhibition increased sensitivity to vincristine in a long-term 3D drug treatment assay of Group 3 MB. Thus, by combining scRNAseq and 3D OrbiSIMS in a relevant model system we were able to define MB subgroup heterogeneity at the single cell level and elucidate new druggable biomarkers for aggressive Group 3 and low-risk SHH MB.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Cerebelosas , Proteínas Hedgehog , Meduloblastoma , Humanos , Neoplasias Cerebelosas/metabolismo , Neoplasias Cerebelosas/patología , Proteínas Hedgehog/metabolismo , Hidrogeles/uso terapéutico , Meduloblastoma/metabolismo , Meduloblastoma/patología , Factor 2 Relacionado con NF-E2 , Análisis de la Célula Individual , RNA-Seq
2.
J Med Internet Res ; 24(12): e40035, 2022 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-36322788

RESUMEN

BACKGROUND: COVID-19 data have been generated across the United Kingdom as a by-product of clinical care and public health provision, as well as numerous bespoke and repurposed research endeavors. Analysis of these data has underpinned the United Kingdom's response to the pandemic, and informed public health policies and clinical guidelines. However, these data are held by different organizations, and this fragmented landscape has presented challenges for public health agencies and researchers as they struggle to find relevant data to access and interrogate the data they need to inform the pandemic response at pace. OBJECTIVE: We aimed to transform UK COVID-19 diagnostic data sets to be findable, accessible, interoperable, and reusable (FAIR). METHODS: A federated infrastructure model (COVID - Curated and Open Analysis and Research Platform [CO-CONNECT]) was rapidly built to enable the automated and reproducible mapping of health data partners' pseudonymized data to the Observational Medical Outcomes Partnership Common Data Model without the need for any data to leave the data controllers' secure environments, and to support federated cohort discovery queries and meta-analysis. RESULTS: A total of 56 data sets from 19 organizations are being connected to the federated network. The data include research cohorts and COVID-19 data collected through routine health care provision linked to longitudinal health care records and demographics. The infrastructure is live, supporting aggregate-level querying of data across the United Kingdom. CONCLUSIONS: CO-CONNECT was developed by a multidisciplinary team. It enables rapid COVID-19 data discovery and instantaneous meta-analysis across data sources, and it is researching streamlined data extraction for use in a Trusted Research Environment for research and public health analysis. CO-CONNECT has the potential to make UK health data more interconnected and better able to answer national-level research questions while maintaining patient confidentiality and local governance procedures.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Reino Unido/epidemiología
3.
Stem Cells Dev ; 30(24): 1215-1227, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34806414

RESUMEN

Hypertrophic cardiomyopathy (HCM) is characterized by increased left ventricular wall thickness that can lead to devastating conditions such as heart failure and sudden cardiac death. Despite extensive study, the mechanisms mediating many of the associated clinical manifestations remain unknown and human models are required. To address this, human-induced pluripotent stem cell (hiPSC) lines were generated from patients with a HCM-associated mutation (c.ACTC1G301A) and isogenic controls created by correcting the mutation using CRISPR/Cas9 gene editing technology. Cardiomyocytes (hiPSC-CMs) were differentiated from these hiPSCs and analyzed at baseline, and at increased contractile workload (2 Hz electrical stimulation). Released extracellular vesicles (EVs) were isolated and characterized after a 24-h culture period and transcriptomic analysis performed on both hiPSC-CMs and released EVs. Transcriptomic analysis of cellular mRNA showed the HCM mutation caused differential splicing within known HCM pathways, and disrupted metabolic pathways. Analysis at increasing contraction frequency showed further disruption of metabolic gene expression, with an additive effect in the HCM background. Intriguingly, we observed differences in snoRNA cargo within HCM released EVs that specifically altered when HCM hiPSC-CMs were subjected to increased workload. These snoRNAs were predicted to have roles in post-translational modifications and alternative splicing, processes differentially regulated in HCM. As such, the snoRNAs identified in this study may unveil mechanistic insight into unexplained HCM phenotypes and offer potential future use as HCM biomarkers or as targets in future RNA-targeting therapies.


Asunto(s)
Cardiomiopatía Hipertrófica , Vesículas Extracelulares , Células Madre Pluripotentes Inducidas , Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/metabolismo , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Mutación/genética , Miocitos Cardíacos , ARN Nucleolar Pequeño/metabolismo , ARN Nucleolar Pequeño/farmacología , Transcriptoma/genética
4.
PLoS Comput Biol ; 17(6): e1009108, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34115749

RESUMEN

Staphylococcus aureus is a serious human and animal pathogen threat exhibiting extraordinary capacity for acquiring new antibiotic resistance traits in the pathogen population worldwide. The development of fast, affordable and effective diagnostic solutions capable of discriminating between antibiotic-resistant and susceptible S. aureus strains would be of huge benefit for effective disease detection and treatment. Here we develop a diagnostics solution that uses Matrix-Assisted Laser Desorption/Ionisation-Time of Flight Mass Spectrometry (MALDI-TOF) and machine learning, to identify signature profiles of antibiotic resistance to either multidrug or benzylpenicillin in S. aureus isolates. Using ten different supervised learning techniques, we have analysed a set of 82 S. aureus isolates collected from 67 cows diagnosed with bovine mastitis across 24 farms. For the multidrug phenotyping analysis, LDA, linear SVM, RBF SVM, logistic regression, naïve Bayes, MLP neural network and QDA had Cohen's kappa values over 85.00%. For the benzylpenicillin phenotyping analysis, RBF SVM, MLP neural network, naïve Bayes, logistic regression, linear SVM, QDA, LDA, and random forests had Cohen's kappa values over 85.00%. For the benzylpenicillin the diagnostic systems achieved up to (mean result ± standard deviation over 30 runs on the test set): accuracy = 97.54% ± 1.91%, sensitivity = 99.93% ± 0.25%, specificity = 95.04% ± 3.83%, and Cohen's kappa = 95.04% ± 3.83%. Moreover, the diagnostic platform complemented by a protein-protein network and 3D structural protein information framework allowed the identification of five molecular determinants underlying the susceptible and resistant profiles. Four proteins were able to classify multidrug-resistant and susceptible strains with 96.81% ± 0.43% accuracy. Five proteins, including the previous four, were able to classify benzylpenicillin resistant and susceptible strains with 97.54% ± 1.91% accuracy. Our approach may open up new avenues for the development of a fast, affordable and effective day-to-day diagnostic solution, which would offer new opportunities for targeting resistant bacteria.


Asunto(s)
Diagnóstico por Computador/veterinaria , Mastitis Bovina/diagnóstico , Penicilina G/farmacología , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus , Animales , Proteínas Bacterianas/química , Bovinos , Biología Computacional , Diagnóstico por Computador/métodos , Diagnóstico por Computador/estadística & datos numéricos , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Mastitis Bovina/tratamiento farmacológico , Mastitis Bovina/microbiología , Staphylococcus aureus Resistente a Meticilina/química , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Mapas de Interacción de Proteínas , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Aprendizaje Automático Supervisado , Reino Unido
5.
Sci Rep ; 11(1): 7736, 2021 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-33833319

RESUMEN

Streptococcus uberis is one of the leading pathogens causing mastitis worldwide. Identification of S. uberis strains that fail to respond to treatment with antibiotics is essential for better decision making and treatment selection. We demonstrate that the combination of supervised machine learning and matrix-assisted laser desorption ionization/time of flight (MALDI-TOF) mass spectrometry can discriminate strains of S. uberis causing clinical mastitis that are likely to be responsive or unresponsive to treatment. Diagnostics prediction systems trained on 90 individuals from 26 different farms achieved up to 86.2% and 71.5% in terms of accuracy and Cohen's kappa. The performance was further increased by adding metadata (parity, somatic cell count of previous lactation and count of positive mastitis cases) to encoded MALDI-TOF spectra, which increased accuracy and Cohen's kappa to 92.2% and 84.1% respectively. A computational framework integrating protein-protein networks and structural protein information to the machine learning results unveiled the molecular determinants underlying the responsive and unresponsive phenotypes.


Asunto(s)
Antibacterianos/uso terapéutico , Industria Lechera , Aprendizaje Automático , Mastitis Bovina/tratamiento farmacológico , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Infecciones Estreptocócicas/veterinaria , Streptococcus/patogenicidad , Animales , Bovinos , Femenino , Mastitis Bovina/microbiología , Embarazo , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/microbiología , Streptococcus/aislamiento & purificación
6.
Viruses ; 12(10)2020 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-32992478

RESUMEN

Influenza A virus is a major global pathogen of humans, and there is an unmet need for effective antivirals. Current antivirals against influenza A virus directly target the virus and are vulnerable to mutational resistance. Harnessing an effective host antiviral response is an attractive alternative. We show that brief exposure to low, non-toxic doses of thapsigargin (TG), an inhibitor of the sarcoplasmic/endoplasmic reticulum (ER) Ca2+ ATPase pump, promptly elicits an extended antiviral state that dramatically blocks influenza A virus production. Crucially, oral administration of TG protected mice against lethal virus infection and reduced virus titres in the lungs of treated mice. TG-induced ER stress unfolded protein response appears as a key driver responsible for activating a spectrum of host antiviral defences that include an enhanced type I/III interferon response. Our findings suggest that TG is potentially a viable host-centric antiviral for the treatment of influenza A virus infection without the inherent problem of drug resistance.


Asunto(s)
Antivirales/farmacología , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H3N8 del Virus de la Influenza A/crecimiento & desarrollo , Tapsigargina/farmacología , Replicación Viral/efectos de los fármacos , Animales , Línea Celular , Embrión de Pollo , Chlorocebus aethiops , Perros , Estrés del Retículo Endoplásmico/efectos de los fármacos , Femenino , Interacciones Huésped-Patógeno/efectos de los fármacos , Humanos , Inmunidad Innata/efectos de los fármacos , Inmunidad Innata/inmunología , Gripe Humana/tratamiento farmacológico , Interferón Tipo I/efectos de los fármacos , Interferón Tipo I/inmunología , Interferones/efectos de los fármacos , Interferones/inmunología , Ratones , Ratones Endogámicos BALB C , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico/antagonistas & inhibidores , Porcinos , Respuesta de Proteína Desplegada/efectos de los fármacos , Células Vero , Interferón lambda
7.
Brain Res ; 1675: 51-60, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-28866055

RESUMEN

Iris neural stem/progenitor cells from mature porcine eyes were investigated using a new protocol for tissue culture, which consists of dispase treatment and Matrigel embedding. We used a number of culture conditions and found an intense differentiation of neuronal cells from both the iris pigmented epithelial (IPE) cells and the stroma tissue cells. Rod photoreceptor-like cells were also observed but mostly in a later stage of culture. Neuronal differentiation does not require any additives such as fetal bovine serum or FGF2, although FGF2 and IGF2 appeared to promote neural differentiation in the IPE cultures. Furthermore, the stroma-derived cells were able to be maintained in vitro indefinitely. The evolutionary similarity between humans and domestic pigs highlight the potential for this methodology in the modeling of human diseases and characterizing human ocular stem cells.


Asunto(s)
Diferenciación Celular/fisiología , Iris/citología , Iris/fisiología , Células-Madre Neurales/fisiología , Neuronas/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Animales , Células Cultivadas , Iris/química , Células-Madre Neurales/química , Neuronas/química , Células Fotorreceptoras Retinianas Bastones/química , Sus scrofa , Porcinos
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