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1.
Front Psychol ; 13: 713678, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35391961

RESUMO

Many frameworks exist that explain how people interact with avatars. Our core argument is that the primary theoretical mechanisms of a user-avatar bond (i.e., UAB) rest with the way people engage avatars and, thereby, the broader digital environment. To understand and predict such engagement, we identify a person's skill in handling/engaging the avatar in the digital environment as an ordering parameter (i.e., organizing predictor). Accordingly, we define skill as a person's ability to enact their agency successfully to achieve desired states. To explain how skill orders experience, we ground our theorizing in ecological perception and systems theory. In our explication, we describe how stable action coupling (i.e., the linking of action inputs to perceived outcomes) enables a state of embeddedness (i.e., when the environment facilitates and constrains behaviors) in the digital environment. Then, we explain how embeddedness promotes motivational attunement (i.e., orienting of motivational systems) and what the digital environment affords to users at different levels of skill. Throughout, we consider how our theoretical scaffolding generates tractable contentions regarding how skill influences UABs.

2.
PLoS One ; 15(11): e0242516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211749

RESUMO

Small (s)RNAs play crucial roles in the regulation of gene expression and genome stability across eukaryotes where they direct epigenetic modifications, post-transcriptional gene silencing, and defense against both endogenous and exogenous viruses. It is known that Chlamydomonas reinhardtii, a well-studied unicellular green algae species, possesses sRNA-based mechanisms that are distinct from those of land plants. However, definition of sRNA loci and further systematic classification is not yet available for this or any other algae. Here, using data-driven machine learning approaches including Multiple Correspondence Analysis (MCA) and clustering, we have generated a comprehensively annotated and classified sRNA locus map for C. reinhardtii. This map shows some common characteristics with higher plants and animals, but it also reveals distinct features. These results are consistent with the idea that there was diversification in sRNA mechanisms after the evolutionary divergence of algae from higher plant lineages.


Assuntos
Chlamydomonas reinhardtii/genética , Loci Gênicos , RNA Antissenso/genética , RNA de Plantas/genética , Composição de Bases , Análise por Conglomerados , Metilação de DNA , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Aprendizado de Máquina , Anotação de Sequência Molecular
3.
Metab Eng ; 60: 168-182, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32335188

RESUMO

Bio-based production of industrial chemicals using synthetic biology can provide alternative green routes from renewable resources, allowing for cleaner production processes. To efficiently produce chemicals on-demand through microbial strain engineering, biomanufacturing foundries have developed automated pipelines that are largely compound agnostic in their time to delivery. Here we benchmark the capabilities of a biomanufacturing pipeline to enable rapid prototyping of microbial cell factories for the production of chemically diverse industrially relevant material building blocks. Over 85 days the pipeline was able to produce 17 potential material monomers and key intermediates by combining 160 genetic parts into 115 unique biosynthetic pathways. To explore the scale-up potential of our prototype production strains, we optimized the enantioselective production of mandelic acid and hydroxymandelic acid, achieving gram-scale production in fed-batch fermenters. The high success rate in the rapid design and prototyping of microbially-produced material building blocks reveals the potential role of biofoundries in leading the transition to sustainable materials production.


Assuntos
Bactérias/metabolismo , Microbiologia Industrial/métodos , Engenharia Metabólica/métodos , Benchmarking , Vias Biossintéticas , Indústria Química , Simulação por Computador , Fermentação , Ácidos Mandélicos/metabolismo , Estereoisomerismo
4.
Sci Rep ; 9(1): 19033, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31836745

RESUMO

Tackling the pressing sustainability needs of society will require the development and application of new technologies. Biotechnology, emboldened by recent advances in synthetic biology, offers to generate sustainable biologically-based routes to chemicals and materials as alternatives to fossil-derived incumbents. Yet, the sustainability potential of biotechnology is not without trade-offs. Here, we probe this capacity for sustainability for the case of bio-based nylon using both deliberative and analytical approaches within a framework of Constructive Sustainability Assessment. We highlight the potential for life cycle CO2 and N2O savings with bio-based processes, but report mixed results in other environmental and social impact categories. Importantly, we demonstrate how this knowledge can be generated collaboratively and constructively within companies at an early stage to anticipate consequences and to inform the modification of designs and applications. Application of the approach demonstrated here provides an avenue for technological actors to better understand and become responsive to the sustainability implications of their products, systems and actions.

5.
Bioessays ; 41(9): e1900048, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31264253

RESUMO

The organization of the genome into topologically associated domains (TADs) appears to be a fundamental process occurring across a wide range of eukaryote organisms, and it likely plays an important role in providing an architectural foundation for gene regulation. Initial studies emphasized the remarkable parallels between TAD organization in organisms as diverse as Drosophila and mammals. However, whereas CCCTC-binding factor (CTCF)/cohesin loop extrusion is emerging as a key mechanism for the formation of mammalian topological domains, the genome organization in Drosophila appears to depend primarily on the partitioning of chromatin state domains. Recent work suggesting a fundamental conserved role of chromatin state in building domain architecture is discussed and insights into genome organization from recent studies in Drosophila are considered.


Assuntos
Fator de Ligação a CCCTC/química , Proteínas de Ciclo Celular/metabolismo , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Drosophila/química , Drosophila/genética , Sequência de Aminoácidos , Animais , Fator de Ligação a CCCTC/metabolismo , Cromatina/química , Cromatina/genética , Sequência Conservada , Proteínas de Drosophila/metabolismo , Genoma de Inseto/genética , Mamíferos/genética , Domínios Proteicos , Transcrição Gênica , Coesinas
6.
Sustain Prod Consum ; 20: 58-73, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32051840

RESUMO

Emerging technologies are increasingly promoted on the promise of tackling the grand challenge of sustainability. A range of assessment and governance approaches seek to evaluate these claims, but these tend to be applied disparately and lack widespread operationalisation. They also face specific challenges, such as high levels of uncertainty, when it comes to emerging technologies. Building and reflecting on both theory and practice, this article develops a framework for Constructive Sustainability Assessment (CSA) that enables the application of sustainability assessments to emerging technologies as part of a broader deliberative approach. In order to achieve this, we discuss and critique current approaches to analytical sustainability assessment and review deliberative social science governance frameworks. We then develop the conceptual basis of CSA - blending life-cycle thinking with principles of responsible research and innovation. This results in four design principles - transdisciplinarity, opening-up, exploring uncertainty and anticipation - that can be followed when applying sustainability assessments to emerging technologies. Finally, we discuss the practical implementation of the framework through a three-step process to (a) formulate the sustainability assessment in collaboration with stakeholders, (b) evaluate potential sustainability implications using methods such as anticipatory life-cycle assessment and (c) interpret and explore the results as part of a deliberative process. Through this, CSA facilitates a much-needed transdisciplinary response to enable the governance of emerging technologies towards sustainability. The framework will be of interest to scientists, engineers, and policy-makers working with emerging technologies that have sustainability as an explicit or implicit motivator.

7.
J Pathol Clin Res ; 4(3): 154-166, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29659191

RESUMO

ARID1A is a tumour suppressor gene that is frequently mutated in clear cell and endometrioid carcinomas of the ovary and endometrium and is an important clinical biomarker for novel treatment approaches for patients with ARID1A defects. However, the accuracy of ARID1A immunohistochemistry (IHC) as a surrogate for mutation status has not fully been established for patient stratification in clinical trials. Here we tested whether ARID1A IHC could reliably predict ARID1A mutations identified by next-generation sequencing. Three commercially available antibodies - EPR13501 (Abcam), D2A8U (Cell Signaling), and HPA005456 (Sigma) - were optimised for IHC using cell line models and human tissue, and screened across a cohort of 45 gynaecological tumours. IHC was scored independently by three pathologists using an immunoreactive score. ARID1A mutation status was assessed using two independent sequencing platforms and the concordance between ARID1A mutation and protein expression was evaluated using Receiver Operating Characteristic statistics. Overall, 21 ARID1A mutations were identified in 14/43 assessable tumours (33%), the majority of which were predicted to be deleterious. Mutations were identified in 6/17 (35%) ovarian clear cell carcinomas, 5/8 (63%) ovarian endometrioid carcinomas, 2/5 (40%) endometrial carcinomas, and 1/7 (14%) carcinosarcomas. ROC analysis identified greater than 95% concordance between mutation status and IHC using a modified immunoreactive score for all three antibodies allowing a definitive cut-point for ARID1A mutant status to be calculated. Comprehensive assessment of concordance of ARID1A IHC and mutation status identified EPR13501 as an optimal antibody, with 100% concordance between ARID1A mutation status and protein expression, across different gynaecological histological subtypes. It delivered the best inter-rater agreement between all pathologists, as well as a clear cost-benefit advantage. This could allow patients to be accurately stratified based on their ARID1A IHC status into early phase clinical trials.


Assuntos
Adenocarcinoma de Células Claras/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Endometrioide/genética , Neoplasias dos Genitais Femininos/genética , Proteínas Nucleares/metabolismo , Neoplasias Ovarianas/genética , Fatores de Transcrição/metabolismo , Adenocarcinoma de Células Claras/diagnóstico , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma Endometrioide/diagnóstico , Carcinoma Endometrioide/metabolismo , Carcinoma Endometrioide/patologia , Proteínas de Ligação a DNA , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Neoplasias dos Genitais Femininos/metabolismo , Neoplasias dos Genitais Femininos/patologia , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Mutação , Proteínas Nucleares/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fatores de Transcrição/genética , Adulto Jovem
9.
Cancer Cell ; 31(1): 79-93, 2017 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-28073006

RESUMO

Chromosomal instability (CIN) contributes to cancer evolution, intratumor heterogeneity, and drug resistance. CIN is driven by chromosome segregation errors and a tolerance phenotype that permits the propagation of aneuploid genomes. Through genomic analysis of colorectal cancers and cell lines, we find frequent loss of heterozygosity and mutations in BCL9L in aneuploid tumors. BCL9L deficiency promoted tolerance of chromosome missegregation events, propagation of aneuploidy, and genetic heterogeneity in xenograft models likely through modulation of Wnt signaling. We find that BCL9L dysfunction contributes to aneuploidy tolerance in both TP53-WT and mutant cells by reducing basal caspase-2 levels and preventing cleavage of MDM2 and BID. Efforts to exploit aneuploidy tolerance mechanisms and the BCL9L/caspase-2/BID axis may limit cancer diversity and evolution.


Assuntos
Aneuploidia , Caspase 2/fisiologia , Neoplasias Colorretais/genética , Cisteína Endopeptidases/fisiologia , Proteínas de Ligação a DNA/fisiologia , Fatores de Transcrição/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/fisiologia , Caspase 2/análise , Segregação de Cromossomos , Cisteína Endopeptidases/análise , Proteínas de Ligação a DNA/genética , Células HCT116 , Humanos , Camundongos , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas c-mdm2/fisiologia , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/fisiologia
10.
Nat Genet ; 46(3): 225-233, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24487277

RESUMO

Clear cell renal carcinomas (ccRCCs) can display intratumor heterogeneity (ITH). We applied multiregion exome sequencing (M-seq) to resolve the genetic architecture and evolutionary histories of ten ccRCCs. Ultra-deep sequencing identified ITH in all cases. We found that 73-75% of identified ccRCC driver aberrations were subclonal, confounding estimates of driver mutation prevalence. ITH increased with the number of biopsies analyzed, without evidence of saturation in most tumors. Chromosome 3p loss and VHL aberrations were the only ubiquitous events. The proportion of C>T transitions at CpG sites increased during tumor progression. M-seq permits the temporal resolution of ccRCC evolution and refines mutational signatures occurring during tumor development.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Mutação , Classe I de Fosfatidilinositol 3-Quinases , Ilhas de CpG , Variações do Número de Cópias de DNA , Proteínas de Ligação a DNA , Progressão da Doença , Evolução Molecular , Exoma , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Histona-Lisina N-Metiltransferase/genética , Humanos , Proteínas Nucleares/genética , Fosfatidilinositol 3-Quinases/genética , Filogenia , Polimorfismo de Nucleotídeo Único , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genética
11.
Cancer Lett ; 340(2): 220-6, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23142290

RESUMO

The notions of inter- and intra-tumour heterogeneity (ITH) have been recognised for many years but recent advances in sequencing technology are allowing the true extent of both forms of heterogeneity to be revealed in detail for the first time. In this review we examine the current evidence for ITH, the possibility of cancers following a branched rather than linear evolutionary path and the potential implications both of these may have for the mechanisms of drug resistance acquisition. We also note that although clearly present in many cases, heterogeneity and branched evolution are not universal, with cases of tumour homogeneity and linear evolution still detected relatively frequently. The complexity induced by cases of ITH presents a considerable challenge for bioinformatics analyses and we illustrate this by describing the specific case of point mutation detection and a number of approaches which have been taken to combat these issues. Equally, the sequencing procedures which generate these data are rendered much more difficult in the face of ITH and we present a discussion of these problems in addition to describing some of the alternate paradigms being considered to overcome them.


Assuntos
Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Testes Genéticos , Genoma Humano , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Neoplasias/genética , Mutação Puntual , Animais , Biologia Computacional , Interpretação Estatística de Dados , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica/estatística & dados numéricos , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Genômica/estatística & dados numéricos , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Humanos , Cariotipagem , Neoplasias/diagnóstico , Neoplasias/terapia , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Medicina de Precisão , Valor Preditivo dos Testes , Prognóstico
12.
N Engl J Med ; 366(10): 883-892, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22397650

RESUMO

BACKGROUND: Intratumor heterogeneity may foster tumor evolution and adaptation and hinder personalized-medicine strategies that depend on results from single tumor-biopsy samples. METHODS: To examine intratumor heterogeneity, we performed exome sequencing, chromosome aberration analysis, and ploidy profiling on multiple spatially separated samples obtained from primary renal carcinomas and associated metastatic sites. We characterized the consequences of intratumor heterogeneity using immunohistochemical analysis, mutation functional analysis, and profiling of messenger RNA expression. RESULTS: Phylogenetic reconstruction revealed branched evolutionary tumor growth, with 63 to 69% of all somatic mutations not detectable across every tumor region. Intratumor heterogeneity was observed for a mutation within an autoinhibitory domain of the mammalian target of rapamycin (mTOR) kinase, correlating with S6 and 4EBP phosphorylation in vivo and constitutive activation of mTOR kinase activity in vitro. Mutational intratumor heterogeneity was seen for multiple tumor-suppressor genes converging on loss of function; SETD2, PTEN, and KDM5C underwent multiple distinct and spatially separated inactivating mutations within a single tumor, suggesting convergent phenotypic evolution. Gene-expression signatures of good and poor prognosis were detected in different regions of the same tumor. Allelic composition and ploidy profiling analysis revealed extensive intratumor heterogeneity, with 26 of 30 tumor samples from four tumors harboring divergent allelic-imbalance profiles and with ploidy heterogeneity in two of four tumors. CONCLUSIONS: Intratumor heterogeneity can lead to underestimation of the tumor genomics landscape portrayed from single tumor-biopsy samples and may present major challenges to personalized-medicine and biomarker development. Intratumor heterogeneity, associated with heterogeneous protein function, may foster tumor adaptation and therapeutic failure through Darwinian selection. (Funded by the Medical Research Council and others.).


Assuntos
Carcinoma de Células Renais/genética , Evolução Molecular , Heterogeneidade Genética , Neoplasias Renais/genética , Fenótipo , Biomarcadores Tumorais , Biópsia , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/secundário , Aberrações Cromossômicas , Everolimo , Exoma , Heterogeneidade Genética/efeitos dos fármacos , Humanos , Imunossupressores/farmacologia , Rim/patologia , Neoplasias Renais/patologia , Mutação , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Filogenia , Ploidias , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Sirolimo/análogos & derivados , Sirolimo/farmacologia
13.
PLoS One ; 5(11): e14093, 2010 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-21124856

RESUMO

BACKGROUND: Enteroaggregative Escherichia coli (EAEC) are defined by their stacked-brick adherence pattern to human epithelial cells. There is no all-encompassing genetic marker for EAEC. The category is commonly implicated in diarrhea but research is hampered by perplexing heterogeneity. METHODOLOGY/PRINCIPAL FINDINGS: To identify key EAEC lineages, we applied multilocus sequence typing to 126 E. coli isolates from a Nigerian case-control study that showed aggregative adherence in the HEp-2 adherence assay, and 24 other EAEC strains from diverse locations. EAEC largely belonged to the A, B1 and D phylogenetic groups and only 7 (4.6%) isolates were in the B2 cluster. As many as 96 sequence types (STs) were identified but 60 (40%) of the EAEC strains belong to or are double locus variants of STs 10, 31, and 394. The remainder did not belong to predominant complexes. The most common ST complex, with predicted ancestor ST10, included 32 (21.3%) of the isolates. Significant age-related distribution suggests that weaned children in Nigeria are at risk for diarrhea from of ST10-complex EAEC. Phylogenetic group D EAEC strains, predominantly from ST31- and ST394 complexes, represented 38 (25.3%) of all isolates, include genome-sequenced strain 042, and possessed conserved chromosomal loci. CONCLUSIONS/SIGNIFICANCE: We have developed a molecular phylogenetic framework, which demonstrates that although grouped by a shared phenotype, the category of 'EAEC' encompasses multiple pathogenic lineages. Principal among isolates from Nigeria were ST10-complex EAEC that were associated with diarrhea in children over one year and ECOR D strains that share horizontally acquired loci.


Assuntos
Proteínas de Bactérias/genética , Escherichia coli/genética , Tipagem de Sequências Multilocus/métodos , Filogenia , Estudos de Casos e Controles , Criança , Diarreia/microbiologia , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Humanos , Nigéria , Virulência/genética
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