RESUMO
Coronavirus Disease 19 (COVID-19) caused by the SARS-CoV-2 virus remains a global pandemic having a serious impact on national economies and healthcare infrastructure. Accurate infection detection protocols are key to policy guidance and decision making. In this pilot study, we compared single versus replicate PCR testing for effective and accurate SARS-CoV-2 infection detection. One-Step Real-Time RT-PCR was employed for the detection of SARS-CoV-2 RNA isolated from individual nasopharyngeal swabs. A total of 10,014 swabs, sampled from the general public (hospital admissions, A&E, elective surgeries, cancer patients, care home residents and healthcare staff), were tested using standard replicate testing. Our analysis demonstrates that approximately 19% of SARS-CoV-2 infected individuals would have been reported as false negative if single sample Real-Time PCR testing was used. Therefore, two replicate tests can substantially decrease the risk of false negative reporting and reduce hospital and community infection rates. As the number of variants of concern increases, we believe that replicate testing is an essential consideration for effective SARS-CoV-2 infection detection and prevention of further outbreaks. A strategic approach limiting the number of missed infections is crucial in controlling the rise of new SARS-CoV-2 variants as well as the management of future pandemics.
Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiologia , Humanos , Pandemias/prevenção & controle , Projetos Piloto , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/genéticaAssuntos
Biomarcadores Tumorais/metabolismo , Hematopoese , Mediadores da Inflamação/metabolismo , Células-Tronco Mesenquimais/patologia , Síndromes Mielodisplásicas/patologia , NF-kappa B/metabolismo , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Células Cultivadas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Células-Tronco Mesenquimais/imunologia , Células-Tronco Mesenquimais/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/metabolismo , NF-kappa B/genética , Prognóstico , Fatores de RiscoRESUMO
Cardiac stem/progenitor cells hold great potential for regenerative therapies; however, the mechanisms regulating their expansion and differentiation remain insufficiently defined. Here we show that Ldb1 is a central regulator of genome organization in cardiac progenitor cells, which is crucial for cardiac lineage differentiation and heart development. We demonstrate that Ldb1 binds to the key regulator of cardiac progenitors, Isl1, and protects it from degradation. Furthermore, the Isl1/Ldb1 complex promotes long-range enhancer-promoter interactions at the loci of the core cardiac transcription factors Mef2c and Hand2. Chromosome conformation capture followed by sequencing identified specific Ldb1-mediated interactions of the Isl1/Ldb1 responsive Mef2c anterior heart field enhancer with genes that play key roles in cardiac progenitor cell function and cardiovascular development. Importantly, the expression of these genes was downregulated upon Ldb1 depletion and Isl1/Ldb1 haplodeficiency. In conclusion, the Isl1/Ldb1 complex orchestrates a network for heart-specific transcriptional regulation and coordination in three-dimensional space during cardiogenesis.
Assuntos
Diferenciação Celular , Cromatina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Genoma , Proteínas com Domínio LIM/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Células-Tronco Multipotentes/citologia , Miócitos Cardíacos/citologia , Fatores de Transcrição/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem da Célula , Cromatina/química , Proteínas de Ligação a DNA/química , Elementos Facilitadores Genéticos/genética , Epistasia Genética , Regulação da Expressão Gênica no Desenvolvimento , Loci Gênicos , Células HEK293 , Coração/embriologia , Humanos , Proteínas com Domínio LIM/química , Fatores de Transcrição MEF2/metabolismo , Células-Tronco Multipotentes/metabolismo , Miócitos Cardíacos/metabolismo , Conformação de Ácido Nucleico , Organogênese , Regiões Promotoras Genéticas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Multimerização Proteica , Estrutura Terciária de Proteína , Proteólise , Peixe-ZebraRESUMO
The first site exhibiting hematopoietic activity in mammalian development is the yolk-sac blood island, which originates from the hemangioblast. Here we performed differentiation assays, as well as genome-wide molecular and functional studies in blast colony-forming cells to gain insight into the function of the essential Ldb1 factor in early primitive hematopoietic development. We show that the previously reported lack of yolk-sac hematopoiesis and vascular development in Ldb1(-/-) mouse result from a decreased number of hemangioblasts and a block in their ability to differentiate into erythroid and endothelial progenitor cells. Transcriptome analysis and correlation with the genome-wide binding pattern of Ldb1 in hemangioblasts revealed a number of direct-target genes and pathways misregulated in the absence of Ldb1. The regulation of essential developmental factors by Ldb1 defines it as an upstream transcriptional regulator of hematopoietic/endothelial development. We show the complex interplay that exists between transcription factors and signaling pathways during the very early stages of hematopoietic/endothelial development and the specific signaling occurring in hemangioblasts in contrast to more advanced hematopoietic developmental stages. Finally, by revealing novel genes and pathways not previously associated with early development, our study provides novel candidate targets to manipulate the differentiation of hematopoietic and/or endothelial cells.
