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1.
Lancet ; 395(10241): 1919-1926, 2020 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-32473682

RESUMEN

BACKGROUND: Individuals with cancer, particularly those who are receiving systemic anticancer treatments, have been postulated to be at increased risk of mortality from COVID-19. This conjecture has considerable effect on the treatment of patients with cancer and data from large, multicentre studies to support this assumption are scarce because of the contingencies of the pandemic. We aimed to describe the clinical and demographic characteristics and COVID-19 outcomes in patients with cancer. METHODS: In this prospective observational study, all patients with active cancer and presenting to our network of cancer centres were eligible for enrolment into the UK Coronavirus Cancer Monitoring Project (UKCCMP). The UKCCMP is the first COVID-19 clinical registry that enables near real-time reports to frontline doctors about the effects of COVID-19 on patients with cancer. Eligible patients tested positive for severe acute respiratory syndrome coronavirus 2 on RT-PCR assay from a nose or throat swab. We excluded patients with a radiological or clinical diagnosis of COVID-19, without a positive RT-PCR test. The primary endpoint was all-cause mortality, or discharge from hospital, as assessed by the reporting sites during the patient hospital admission. FINDINGS: From March 18, to April 26, 2020, we analysed 800 patients with a diagnosis of cancer and symptomatic COVID-19. 412 (52%) patients had a mild COVID-19 disease course. 226 (28%) patients died and risk of death was significantly associated with advancing patient age (odds ratio 9·42 [95% CI 6·56-10·02]; p<0·0001), being male (1·67 [1·19-2·34]; p=0·003), and the presence of other comorbidities such as hypertension (1·95 [1·36-2·80]; p<0·001) and cardiovascular disease (2·32 [1·47-3·64]). 281 (35%) patients had received cytotoxic chemotherapy within 4 weeks before testing positive for COVID-19. After adjusting for age, gender, and comorbidities, chemotherapy in the past 4 weeks had no significant effect on mortality from COVID-19 disease, when compared with patients with cancer who had not received recent chemotherapy (1·18 [0·81-1·72]; p=0·380). We found no significant effect on mortality for patients with immunotherapy, hormonal therapy, targeted therapy, radiotherapy use within the past 4 weeks. INTERPRETATION: Mortality from COVID-19 in cancer patients appears to be principally driven by age, gender, and comorbidities. We are not able to identify evidence that cancer patients on cytotoxic chemotherapy or other anticancer treatment are at an increased risk of mortality from COVID-19 disease compared with those not on active treatment. FUNDING: University of Birmingham, University of Oxford.


Asunto(s)
Antineoplásicos/uso terapéutico , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/mortalidad , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Neumonía Viral/complicaciones , Neumonía Viral/mortalidad , Factores de Edad , Anciano , Betacoronavirus , COVID-19 , Causas de Muerte , Comorbilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Pandemias , Estudios Prospectivos , Factores de Riesgo , SARS-CoV-2 , Factores Sexuales
2.
Epigenetics Chromatin ; 12(1): 33, 2019 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-31164147

RESUMEN

BACKGROUND: Both tissue-specific and ubiquitously expressed transcription factors, such as Sp-family members, are required for correct development. However, the molecular details of how ubiquitous factors are involved in programming tissue-specific chromatin and thus participate in developmental processes are still unclear. We previously showed that embryonic stem cells lacking Sp1 DNA-binding activity (Sp1ΔDBD/ΔDBD cells) are able to differentiate into early blood progenitors despite the inability of Sp1 to bind chromatin without its DNA-binding domain. However, gene expression during differentiation becomes progressively deregulated, and terminal differentiation is severely compromised. RESULTS: Here, we studied the cooperation of Sp1 with its closest paralogue Sp3 in hematopoietic development and demonstrate that Sp1 and Sp3 binding sites largely overlap. The complete absence of either Sp1 or Sp3 or the presence of the Sp1 DNA-binding mutant has only a minor effect on the pattern of distal accessible chromatin sites and their transcription factor binding motif content, suggesting that these mutations do not affect tissue-specific chromatin programming. Sp3 cooperates with Sp1ΔDBD/ΔDBD to enable hematopoiesis, but is unable to do so in the complete absence of Sp1. Using single-cell gene expression analysis, we show that the lack of Sp1 DNA binding leads to a distortion of cell fate decision timing, indicating that stable chromatin binding of Sp1 is required to maintain robust differentiation trajectories. CONCLUSIONS: Our findings highlight the essential contribution of ubiquitous factors such as Sp1 to blood cell development. In contrast to tissue-specific transcription factors which are required to direct specific cell fates, loss of Sp1 leads to a widespread deregulation in timing and coordination of differentiation trajectories during hematopoietic specification.


Asunto(s)
Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Factor de Transcripción Sp1/metabolismo , Factor de Transcripción Sp3/metabolismo , Animales , Sitios de Unión , Diferenciación Celular/genética , Línea Celular , Proteínas de Unión al ADN/metabolismo , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Ratones , Regiones Promotoras Genéticas , Unión Proteica , Factores de Transcripción/metabolismo , Factores de Transcripción/fisiología , Transcripción Genética
3.
Cell ; 162(3): 527-39, 2015 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-26232223

RESUMEN

About 12,000 years ago in the Near East, humans began the transition from hunter-gathering to agriculture-based societies. Barley was a founder crop in this process, and the most important steps in its domestication were mutations in two adjacent, dominant, and complementary genes, through which grains were retained on the inflorescence at maturity, enabling effective harvesting. Independent recessive mutations in each of these genes caused cell wall thickening in a highly specific grain "disarticulation zone," converting the brittle floral axis (the rachis) of the wild-type into a tough, non-brittle form that promoted grain retention. By tracing the evolutionary history of allelic variation in both genes, we conclude that spatially and temporally independent selections of germplasm with a non-brittle rachis were made during the domestication of barley by farmers in the southern and northern regions of the Levant, actions that made a major contribution to the emergence of early agrarian societies.


Asunto(s)
Evolución Biológica , Hordeum/fisiología , Dispersión de Semillas , Secuencia de Aminoácidos , Hordeum/anatomía & histología , Hordeum/genética , Datos de Secuencia Molecular , Fenotipo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Alineación de Secuencia
4.
PLoS One ; 9(3): e85761, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24614886

RESUMEN

Using Roche/454 technology, we sequenced the chloroplast genomes of 12 Triticeae species, including bread wheat, barley and rye, as well as the diploid progenitors and relatives of bread wheat Triticum urartu, Aegilops speltoides and Ae. tauschii. Two wild tetraploid taxa, Ae. cylindrica and Ae. geniculata, were also included. Additionally, we incorporated wild Einkorn wheat Triticum boeoticum and its domesticated form T. monococcum and two Hordeum spontaneum (wild barley) genotypes. Chloroplast genomes were used for overall sequence comparison, phylogenetic analysis and dating of divergence times. We estimate that barley diverged from rye and wheat approximately 8-9 million years ago (MYA). The genome donors of hexaploid wheat diverged between 2.1-2.9 MYA, while rye diverged from Triticum aestivum approximately 3-4 MYA, more recently than previously estimated. Interestingly, the A genome taxa T. boeoticum and T. urartu were estimated to have diverged approximately 570,000 years ago. As these two have a reproductive barrier, the divergence time estimate also provides an upper limit for the time required for the formation of a species boundary between the two. Furthermore, we conclusively show that the chloroplast genome of hexaploid wheat was contributed by the B genome donor and that this unknown species diverged from Ae. speltoides about 980,000 years ago. Additionally, sequence alignments identified a translocation of a chloroplast segment to the nuclear genome which is specific to the rye/wheat lineage. We propose the presented phylogeny and divergence time estimates as a reference framework for future studies on Triticeae.


Asunto(s)
Evolución Molecular , Genoma del Cloroplasto/genética , Genoma de Planta/genética , Hordeum/genética , Secale/genética , Análisis de Secuencia de ADN , Triticum/genética , Secuencia de Bases , Teorema de Bayes , Núcleo Celular/genética , Cloroplastos/genética , Mapeo Cromosómico , Haplotipos/genética , Datos de Secuencia Molecular , Filogenia , Poliploidía , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie , Factores de Tiempo
5.
Plant J ; 73(2): 347-56, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23057663

RESUMEN

A 454 sequencing snapshot was utilised to investigate the genome composition and nucleotide diversity of transposable elements (TEs) for several Triticeae taxa, including Triticum aestivum, Hordeum vulgare, Hordeum spontaneum and Secale cereale together with relatives of the A, B and D genome donors of wheat, Triticum urartu (A), Aegilops speltoides (S) and Aegilops tauschii (D). Additional taxa containing the A genome, Triticum monococcum and its wild relative Triticum boeoticum, were also included. The main focus of the analysis was on the genomic composition of TEs as these make up at least 80% of the overall genome content. Although more than 200 TE families were identified in each species, approximately 50% of the overall genome comprised 12-15 TE families. The BARE1 element was the largest contributor to all genomes, contributing more than 10% to the overall genome. We also found that several TE families differ strongly in their abundance between species, indicating that TE families can thrive extremely successfully in one species while going virtually extinct in another. Additionally, the nucleotide diversity of BARE1 populations within individual genomes was measured. Interestingly, the nucleotide diversity in the domesticated barley H. vulgare cv. Barke was found to be twice as high as in its wild progenitor H. spontaneum, suggesting that the domesticated barley gained nucleotide diversity from the addition of different genotypes during the domestication and breeding process. In the rye/wheat lineage, sequence diversity of BARE1 elements was generally higher, suggesting that factors such as geographical distribution and mating systems might play a role in intragenomic TE diversity.


Asunto(s)
Elementos Transponibles de ADN/fisiología , ADN de Plantas/genética , Genoma de Planta , Poaceae/genética , Poaceae/metabolismo , Elementos Transponibles de ADN/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Variación Genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Especificidad de la Especie
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