Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
Cell ; 155(3): 567-81, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24139898

RESUMO

Mutation is a fundamental process in tumorigenesis. However, the degree to which the rate of somatic mutation varies across the human genome and the mechanistic basis underlying this variation remain to be fully elucidated. Here, we performed a cross-cancer comparison of 402 whole genomes comprising a diverse set of childhood and adult tumors, including both solid and hematopoietic malignancies. Surprisingly, we found that the inactive X chromosome of many female cancer genomes accumulates on average twice and up to four times as many somatic mutations per megabase, as compared to the individual autosomes. Whole-genome sequencing of clonally expanded hematopoietic stem/progenitor cells (HSPCs) from healthy individuals and a premalignant myelodysplastic syndrome (MDS) sample revealed no X chromosome hypermutation. Our data suggest that hypermutation of the inactive X chromosome is an early and frequent feature of tumorigenesis resulting from DNA replication stress in aberrantly proliferating cells.


Assuntos
Cromossomos Humanos X , Mutação , Neoplasias/genética , Inativação do Cromossomo X , Adulto , Idoso , Replicação do DNA , Feminino , Humanos , Masculino , Meduloblastoma/genética , Meduloblastoma/patologia , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Polimorfismo de Nucleotídeo Único , Fase S
2.
Nature ; 576(7786): 274-280, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31802000

RESUMO

Embryonal tumours with multilayered rosettes (ETMRs) are aggressive paediatric embryonal brain tumours with a universally poor prognosis1. Here we collected 193 primary ETMRs and 23 matched relapse samples to investigate the genomic landscape of this distinct tumour type. We found that patients with tumours in which the proposed driver C19MC2-4 was not amplified frequently had germline mutations in DICER1 or other microRNA-related aberrations such as somatic amplification of miR-17-92 (also known as MIR17HG). Whole-genome sequencing revealed that tumours had an overall low recurrence of single-nucleotide variants (SNVs), but showed prevalent genomic instability caused by widespread occurrence of R-loop structures. We show that R-loop-associated chromosomal instability can be induced by the loss of DICER1 function. Comparison of primary tumours and matched relapse samples showed a strong conservation of structural variants, but low conservation of SNVs. Moreover, many newly acquired SNVs are associated with a mutational signature related to cisplatin treatment. Finally, we show that targeting R-loops with topoisomerase and PARP inhibitors might be an effective treatment strategy for this deadly disease.


Assuntos
MicroRNAs/genética , Neoplasias Embrionárias de Células Germinativas/genética , RNA Helicases DEAD-box/genética , DNA Topoisomerases Tipo I/genética , Humanos , Mutação , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Inibidores de Poli(ADP-Ribose) Polimerases , Poli(ADP-Ribose) Polimerases/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante , Recidiva , Ribonuclease III/genética
3.
Infection ; 51(6): 1669-1678, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37166617

RESUMO

PURPOSE: Identification of patients at risk of complicated or more severe COVID-19 is of pivotal importance, since these patients might require monitoring, antiviral treatment, and hospitalization. In this study, we prospectively evaluated the SACOV-19 score for its ability to predict complicated or more severe COVID-19. METHODS: In this prospective multicenter study, we included 124 adult patients with acute COVID-19 in three German hospitals, who were diagnosed in an early, uncomplicated stage of COVID-19 within 72 h of inclusion. We determined the SACOV-19 score at baseline and performed a follow-up at 30 days. RESULTS: The SACOV-19 score's AUC was 0.816. At a cutoff of > 3, it predicted deterioration to complicated or more severe COVID-19 with a sensitivity of 94% and a specificity of 55%. It performed significantly better in predicting complicated COVID-19 than the random tree-based SACOV-19 predictive model, the CURB-65, 4C mortality, or qCSI scores. CONCLUSION: The SACOV-19 score is a feasible tool to aid decision making in acute COVID-19.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/diagnóstico , Estudos Prospectivos , SARS-CoV-2 , Hospitalização , Hospitais
4.
Nature ; 548(7668): 456-460, 2017 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-28813413

RESUMO

Developmental deconvolution of complex organs and tissues at the level of individual cells remains challenging. Non-invasive genetic fate mapping has been widely used, but the low number of distinct fluorescent marker proteins limits its resolution. Much higher numbers of cell markers have been generated using viral integration sites, viral barcodes, and strategies based on transposons and CRISPR-Cas9 genome editing; however, temporal and tissue-specific induction of barcodes in situ has not been achieved. Here we report the development of an artificial DNA recombination locus (termed Polylox) that enables broadly applicable endogenous barcoding based on the Cre-loxP recombination system. Polylox recombination in situ reaches a practical diversity of several hundred thousand barcodes, allowing tagging of single cells. We have used this experimental system, combined with fate mapping, to assess haematopoietic stem cell (HSC) fates in vivo. Classical models of haematopoietic lineage specification assume a tree with few major branches. More recently, driven in part by the development of more efficient single-cell assays and improved transplantation efficiencies, different models have been proposed, in which unilineage priming may occur in mice and humans at the level of HSCs. We have introduced barcodes into HSC progenitors in embryonic mice, and found that the adult HSC compartment is a mosaic of embryo-derived HSC clones, some of which are unexpectedly large. Most HSC clones gave rise to multilineage or oligolineage fates, arguing against unilineage priming, and suggesting coherent usage of the potential of cells in a clone. The spreading of barcodes, both after induction in embryos and in adult mice, revealed a basic split between common myeloid-erythroid development and common lymphocyte development, supporting the long-held but contested view of a tree-like haematopoietic structure.


Assuntos
Sítios de Ligação Microbiológicos/genética , Linhagem da Célula/genética , Rastreamento de Células/métodos , Código de Barras de DNA Taxonômico/métodos , Células-Tronco Hematopoéticas/citologia , Recombinação Genética/genética , Análise de Célula Única/métodos , Animais , Células Clonais/citologia , Células Clonais/metabolismo , Embrião de Mamíferos/citologia , Células Eritroides/citologia , Células Eritroides/metabolismo , Feminino , Células-Tronco Hematopoéticas/metabolismo , Integrases/metabolismo , Linfócitos/citologia , Linfócitos/metabolismo , Masculino , Camundongos , Mosaicismo , Células Mieloides/citologia , Células Mieloides/metabolismo
5.
Nature ; 547(7663): 311-317, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28726821

RESUMO

Current therapies for medulloblastoma, a highly malignant childhood brain tumour, impose debilitating effects on the developing child, and highlight the need for molecularly targeted treatments with reduced toxicity. Previous studies have been unable to identify the full spectrum of driver genes and molecular processes that operate in medulloblastoma subgroups. Here we analyse the somatic landscape across 491 sequenced medulloblastoma samples and the molecular heterogeneity among 1,256 epigenetically analysed cases, and identify subgroup-specific driver alterations that include previously undiscovered actionable targets. Driver mutations were confidently assigned to most patients belonging to Group 3 and Group 4 medulloblastoma subgroups, greatly enhancing previous knowledge. New molecular subtypes were differentially enriched for specific driver events, including hotspot in-frame insertions that target KBTBD4 and 'enhancer hijacking' events that activate PRDM6. Thus, the application of integrative genomics to an extensive cohort of clinical samples derived from a single childhood cancer entity revealed a series of cancer genes and biologically relevant subtype diversity that represent attractive therapeutic targets for the treatment of patients with medulloblastoma.


Assuntos
Análise Mutacional de DNA , Genoma Humano/genética , Meduloblastoma/classificação , Meduloblastoma/genética , Sequenciamento Completo do Genoma , Carcinogênese/genética , Proteínas de Transporte/genética , Estudos de Coortes , Metilação de DNA , Conjuntos de Dados como Assunto , Epistasia Genética , Genômica , Humanos , Terapia de Alvo Molecular , Proteínas Musculares/genética , Mutação , Oncogenes/genética , Fatores de Transcrição/genética , Proteínas Wnt/genética
6.
J Chem Phys ; 159(13)2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37787132

RESUMO

The precipitation of struvite, a magnesium ammonium phosphate hexahydrate (MgNH4PO4 · 6H2O) mineral, from wastewater is a promising method for recovering phosphorous. While this process is commonly used in engineered environments, our understanding of the underlying mechanisms responsible for the formation of struvite crystals remains limited. Specifically, indirect evidence suggests the involvement of an amorphous precursor and the occurrence of multi-step processes in struvite formation, which would indicate non-classical paths of nucleation and crystallization. In this study, we use synchrotron-based in situ x-ray scattering complemented by cryogenic transmission electron microscopy to obtain new insights from the earliest stages of struvite formation. The holistic scattering data captured the structure of an entire assembly in a time-resolved manner. The structural features comprise the aqueous medium, the growing struvite crystals, and any potential heterogeneities or complex entities. By analysing the scattering data, we found that the onset of crystallization causes a perturbation in the structure of the surrounding aqueous medium. This perturbation is characterized by the occurrence and evolution of Ornstein-Zernike fluctuations on a scale of about 1 nm, suggesting a non-classical nature of the system. We interpret this phenomenon as a liquid-liquid phase separation, which gives rise to the formation of the amorphous precursor phase preceding actual crystal growth of struvite. Our microscopy results confirm that the formation of Mg-struvite includes a short-lived amorphous phase, lasting >10 s.

7.
Eur J Immunol ; 51(1): 250-252, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32761616

RESUMO

In mouse myocardial infarction, we combined lineage tracing of cardiac macrophages, mapping their ontogeny, with an analysis of their phenotype and phagocytic functions. While embryo-derived macrophages were most abundant in homeostasis, bone marrow-derived MHC-IIlo macrophages increased in both numbers and phagocytic capacity to clear necrotic cardiomyocytes early after ischemia/perfusion injury.


Assuntos
Antígenos de Histocompatibilidade Classe II/metabolismo , Macrófagos/imunologia , Infarto do Miocárdio/imunologia , Miocárdio/imunologia , Animais , Receptor 1 de Quimiocina CX3C/metabolismo , Modelos Animais de Doenças , Embrião de Mamíferos/citologia , Embrião de Mamíferos/imunologia , Macrófagos/patologia , Camundongos , Camundongos Transgênicos , Infarto do Miocárdio/patologia , Miocárdio/patologia , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/patologia , Fagocitose/imunologia
8.
Eur J Nutr ; 61(5): 2847-2851, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35266046

RESUMO

PURPOSE: Caffeinated beverages are consumed daily throughout the world. Caffeine consumption has been linked to dysfunction of the autonomic nervous system. However, the exact effects are still insufficiently understood. METHODS: Sixteen healthy individuals were included in the present non-randomized cross-over interventional study. All study subjects consumed a commercial energy drink (containing 240 mg caffeine), and in a second independent session coffee (containing 240 mg caffeine). High-resolution digital ECGs in Frank-lead configuration were recorded at baseline before consumption, and 45 min after consumption of the respective beverage. Using customized software, we assessed ECG-based biomarker periodic repolarization dynamics (PRD), which mirrors the effect of efferent cardiac sympathetic activity on the ventricular myocardium. RESULTS: The consumption of energy drinks resulted in an increase in PRD levels (3.64 vs. 5.85 deg2; p < 0.001). In contrast, coffee consumption did not alter PRD levels (3.47 vs 3.16 deg2, p = 0.63). The heart rates remained unchanged both after coffee and after energy drink consumption. Spearman analysis showed no significant correlation between PRD changes and heart rate changes (R = 0.34, p = 0.31 for coffee, R = 0.31, p = 0.24 for energy drink). CONCLUSION: Our data suggests that sympathetic activation after consumption of caffeinated beverages is independent from caffeine and might be mediated by other substances. TRIAL NUMBER: NCT04886869, 13 May 2021, retrospectively registered.


Assuntos
Bebidas Energéticas , Cafeína , Café , Estudos Cross-Over , Frequência Cardíaca , Humanos
9.
Angew Chem Int Ed Engl ; 61(40): e202208475, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35785466

RESUMO

Small-molecular-weight (MW) additives can strongly impact amorphous calcium carbonate (ACC), playing an elusive role in biogenic, geologic, and industrial calcification. Here, we present molecular mechanisms by which these additives regulate stability and composition of both CaCO3 solutions and solid ACC. Potent antiscalants inhibit ACC precipitation by interacting with prenucleation clusters (PNCs); they specifically trigger and integrate into PNCs or feed PNC growth actively. Only PNC-interacting additives are traceable in ACC, considerably stabilizing it against crystallization. The selective incorporation of potent additives in PNCs is a reliable chemical label that provides conclusive chemical evidence that ACC is a molecular PNC-derived precipitate. Our results reveal additive-cluster interactions beyond established mechanistic conceptions. They reassess the role of small-MW molecules in crystallization and biomineralization while breaking grounds for new sustainable antiscalants.


Assuntos
Carbonato de Cálcio , Carbonato de Cálcio/química , Cristalização , Peso Molecular
10.
Acta Neuropathol ; 142(1): 191-210, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33929593

RESUMO

The genetic basis of brain tumor development is poorly understood. Here, leukocyte DNA of 21 patients from 15 families with ≥ 2 glioma cases each was analyzed by whole-genome or targeted sequencing. As a result, we identified two families with rare germline variants, p.(A592T) or p.(A817V), in the E-cadherin gene CDH1 that co-segregate with the tumor phenotype, consisting primarily of oligodendrogliomas, WHO grade II/III, IDH-mutant, 1p/19q-codeleted (ODs). Rare CDH1 variants, previously shown to predispose to gastric and breast cancer, were significantly overrepresented in these glioma families (13.3%) versus controls (1.7%). In 68 individuals from 28 gastric cancer families with pathogenic CDH1 germline variants, brain tumors, including a pituitary adenoma, were observed in three cases (4.4%), a significantly higher prevalence than in the general population (0.2%). Furthermore, rare CDH1 variants were identified in tumor DNA of 6/99 (6%) ODs. CDH1 expression was detected in undifferentiated and differentiating oligodendroglial cells isolated from rat brain. Functional studies using CRISPR/Cas9-mediated knock-in or stably transfected cell models demonstrated that the identified CDH1 germline variants affect cell membrane expression, cell migration and aggregation. E-cadherin ectodomain containing variant p.(A592T) had an increased intramolecular flexibility in a molecular dynamics simulation model. E-cadherin harboring intracellular variant p.(A817V) showed reduced ß-catenin binding resulting in increased cytosolic and nuclear ß-catenin levels reverted by treatment with the MAPK interacting serine/threonine kinase 1 inhibitor CGP 57380. Our data provide evidence for a role of deactivating CDH1 variants in the risk and tumorigenesis of neuroepithelial and epithelial brain tumors, particularly ODs, possibly via WNT/ß-catenin signaling.


Assuntos
Antígenos CD/genética , Neoplasias Encefálicas/genética , Caderinas/genética , Carcinoma/genética , Neoplasias Neuroepiteliomatosas/genética , Adenoma/genética , Adenoma/patologia , Compostos de Anilina/uso terapêutico , Animais , Diversidade de Anticorpos , Neoplasias Encefálicas/tratamento farmacológico , Carcinoma/tratamento farmacológico , DNA de Neoplasias/genética , Técnicas de Introdução de Genes , Variação Genética , Células HEK293 , Humanos , Neoplasias Neuroepiteliomatosas/tratamento farmacológico , Oligodendroglioma/genética , Oligodendroglioma/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Purinas/uso terapêutico , Ratos , Ratos Sprague-Dawley , Sequenciamento Completo do Genoma
11.
Arch Orthop Trauma Surg ; 141(1): 1-16, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32172318

RESUMO

INTRODUCTION: Global discussions regarding the treatment of Legg-Calvé-Perthes disease (LCPD) are still controversial. The aim of this study was to characterize the worldwide regional differences in nonoperative and operative treatment for LCPD. MATERIALS AND METHODS: Based on a comprehensive literature search, 123 studies describing the results of nonoperative and operative treatment for LCPD were included. Overall, disease and outcome parameters of 6,968 hips were recorded and compared among the continents-Europe, North America, Asia, Africa, South America, and Australia. RESULTS: Our results showed that the continents differed regarding initial disease progression and therapeutic decision-making, but the final outcome was comparable. The reported proportion of affected hips with mild presentation tended to be higher in Europe, North America, and Africa, whereas disease progression was more severe in Asia, Australia, and South America. Nonoperative treatment was reported more frequently in Europe and North America, while operative management was more common in the rest of the world. Femoral osteotomy was performed more frequently than pelvic osteotomy worldwide, but pelvic osteotomy was comparably more common in North America, Australia, and South America. CONCLUSIONS: The continents differed in terms of therapies for LCPD, while the final outcome was similar. Studies with greater evidence and larger sample size are needed to evaluate the effect of therapeutic measures on LCPD outcome. LEVEL OF EVIDENCE: III (systematic review of level III studies).


Assuntos
Doença de Legg-Calve-Perthes/terapia , Progressão da Doença , Fêmur/cirurgia , Humanos , Osteotomia , Pelve/cirurgia , Resultado do Tratamento
12.
Nature ; 511(7510): 428-34, 2014 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-25043047

RESUMO

Medulloblastoma is a highly malignant paediatric brain tumour currently treated with a combination of surgery, radiation and chemotherapy, posing a considerable burden of toxicity to the developing child. Genomics has illuminated the extensive intertumoral heterogeneity of medulloblastoma, identifying four distinct molecular subgroups. Group 3 and group 4 subgroup medulloblastomas account for most paediatric cases; yet, oncogenic drivers for these subtypes remain largely unidentified. Here we describe a series of prevalent, highly disparate genomic structural variants, restricted to groups 3 and 4, resulting in specific and mutually exclusive activation of the growth factor independent 1 family proto-oncogenes, GFI1 and GFI1B. Somatic structural variants juxtapose GFI1 or GFI1B coding sequences proximal to active enhancer elements, including super-enhancers, instigating oncogenic activity. Our results, supported by evidence from mouse models, identify GFI1 and GFI1B as prominent medulloblastoma oncogenes and implicate 'enhancer hijacking' as an efficient mechanism driving oncogene activation in a childhood cancer.


Assuntos
Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos/genética , Variação Estrutural do Genoma/genética , Meduloblastoma/genética , Oncogenes/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Animais , Criança , Cromossomos Humanos Par 9/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Meduloblastoma/classificação , Meduloblastoma/patologia , Camundongos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
13.
Nature ; 510(7506): 537-41, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24847876

RESUMO

Epigenetic alterations, that is, disruption of DNA methylation and chromatin architecture, are now acknowledged as a universal feature of tumorigenesis. Medulloblastoma, a clinically challenging, malignant childhood brain tumour, is no exception. Despite much progress from recent genomics studies, with recurrent changes identified in each of the four distinct tumour subgroups (WNT-pathway-activated, SHH-pathway-activated, and the less-well-characterized Group 3 and Group 4), many cases still lack an obvious genetic driver. Here we present whole-genome bisulphite-sequencing data from thirty-four human and five murine tumours plus eight human and three murine normal controls, augmented with matched whole-genome, RNA and chromatin immunoprecipitation sequencing data. This comprehensive data set allowed us to decipher several features underlying the interplay between the genome, epigenome and transcriptome, and its effects on medulloblastoma pathophysiology. Most notable were highly prevalent regions of hypomethylation correlating with increased gene expression, extending tens of kilobases downstream of transcription start sites. Focal regions of low methylation linked to transcription-factor-binding sites shed light on differential transcriptional networks between subgroups, whereas increased methylation due to re-normalization of repressed chromatin in DNA methylation valleys was positively correlated with gene expression. Large, partially methylated domains affecting up to one-third of the genome showed increased mutation rates and gene silencing in a subgroup-specific fashion. Epigenetic alterations also affected novel medulloblastoma candidate genes (for example, LIN28B), resulting in alternative promoter usage and/or differential messenger RNA/microRNA expression. Analysis of mouse medulloblastoma and precursor-cell methylation demonstrated a somatic origin for many alterations. Our data provide insights into the epigenetic regulation of transcription and genome organization in medulloblastoma pathogenesis, which are probably also of importance in a wider developmental and disease context.


Assuntos
Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Meduloblastoma/genética , Análise de Sequência de DNA/métodos , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Feminino , Genoma/genética , Histonas/metabolismo , Humanos , Meduloblastoma/patologia , Camundongos , Regiões Promotoras Genéticas/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
14.
J Am Chem Soc ; 141(11): 4490-4504, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30753066

RESUMO

"Non-classical" notions consider formation pathways of crystalline materials where larger species than monomeric chemical constituents, i.e., ions or single molecules, play crucial roles, which are not covered by the classical theories dating back to the 1870s and 1920s. Providing an outline of "non-classical" nucleation, we demonstrate that prenucleation clusters (PNCs) can lie on alternative pathways to phase separation, where the very event of demixing is primarily based on not the sizes of the species forming, as in the classical view, but their dynamics. Rationalizing, on the other hand, that precursors that can be analytically detected in pre-nucleation stages and that play a role in phase separation must be considered PNCs and cannot be explained by classical notions, we outline a variety of systems where PNCs are important. Indeed, in recent years, with the advent of "non-classical" theories, a primary focus of research concentrated on the fundamental understanding of oligomeric/polymeric and particulate species involved in nucleation and crystallization processes, respectively. At the same time, the near-to unfathomable potential of "non-classical" routes for the synthesis of inorganic functional materials slowly unfolds. An overview of recent developments in the fundamental and mechanistic understanding of "non-classical" nucleation and crystallization in this Perspective then allows us to map out the potential of cluster/particle-driven mineralization pathways to intrinsically tailor the properties of inorganic functional (hybrid) materials via structuration from the nano- to the mesoscale. This is of utter importance for the functionality and performance of materials, as it may even confer emergent properties such as self-healing. Biominerals-often formed via particle accretion mechanisms-demonstrate this impressively and thus can serve as a further source of inspiration how to exploit nonclassical crystallization routes for syntheses of structured and functional materials. These new avenues to synthetic approaches may finally provide a holistic material concept, in which fundamental chemistry and materials science synergistically alloy.

15.
Int J Cancer ; 141(5): 877-886, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28597939

RESUMO

Precision oncology implies the ability to predict which patients will likely respond to specific cancer therapies based on increasingly accurate, high-resolution molecular diagnostics as well as the functional and mechanistic understanding of individual tumors. While molecular stratification of patients can be achieved through different means, a promising approach is next-generation sequencing of tumor DNA and RNA, which can reveal genomic alterations that have immediate clinical implications. Furthermore, certain genetic alterations are shared across multiple histologic entities, raising the fundamental question of whether tumors should be treated by molecular profile and not tissue of origin. We here describe MASTER (Molecularly Aided Stratification for Tumor Eradication Research), a clinically applicable platform for prospective, biology-driven stratification of younger adults with advanced-stage cancer across all histologies and patients with rare tumors. We illustrate how a standardized workflow for selection and consenting of patients, sample processing, whole-exome/genome and RNA sequencing, bioinformatic analysis, rigorous validation of potentially actionable findings, and data evaluation by a dedicated molecular tumor board enables categorization of patients into different intervention baskets and formulation of evidence-based recommendations for clinical management. Critical next steps will be to increase the number of patients that can be offered comprehensive molecular analysis through collaborations and partnering, to explore ways in which additional technologies can aid in patient stratification and individualization of treatment, to stimulate clinically guided exploratory research projects, and to gradually move away from assessing the therapeutic activity of targeted interventions on a case-by-case basis toward controlled clinical trials of genomics-guided treatments.


Assuntos
Perfilação da Expressão Gênica/métodos , Oncologia/métodos , Neoplasias/genética , Medicina de Precisão/métodos , Humanos , Neoplasias/classificação
16.
Am J Pathol ; 186(10): 2569-76, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27658714

RESUMO

A single dose of N-ethyl-N-nitrosourea (ENU) during late prenatal or early postnatal development induces a high incidence of malignant schwannomas and gliomas in rats. Although T->A mutations in the transmembrane domain of the Neu (c-ErbB-2) gene are the driver mutations in ENU-induced malignant schwannomas, the molecular basis of ENU-induced gliomas remains enigmatic. We performed whole-genome sequencing of gliomas that developed in three BDIV and two BDIX rats exposed to a single dose of 80 mg ENU/kg body weight on postnatal day one. T:A->A:T and T:A->C:G mutations, which are typical for ENU-induced mutagenesis, were predominant (41% to 55% of all somatic single nucleotide mutations). T->A mutations were identified in all five rat gliomas at Braf codon 545 (V545E), which corresponds to the human BRAF V600E. Additional screening revealed that 33 gliomas in BDIV rats and 12 gliomas in BDIX rats all carried a Braf V545E mutation, whereas peritumoral brain tissue of either strain had the wild-type sequence. The gliomas were immunoreactive to BRAF V600E antibody. These results indicate that Braf mutation is a frequent early event in the development of rat gliomas caused by a single dose of ENU.


Assuntos
Etilnitrosoureia/efeitos adversos , Glioma/genética , Neurilemoma/genética , Proteínas Proto-Oncogênicas B-raf/genética , Substituição de Aminoácidos , Animais , Genótipo , Glioma/induzido quimicamente , Mutagênese , Neurilemoma/induzido quimicamente , Mutação Puntual , Proteínas Proto-Oncogênicas B-raf/metabolismo , Ratos , Análise de Sequência de DNA
17.
J Struct Biol ; 196(2): 260-287, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27620641

RESUMO

Recent research has shown that biominerals and their biomimetics (i) typically form via an amorphous precursor phase, and (ii) commonly display a nanogranular texture. Apparently, these two key features are closely related, underlining the fact that the formation of biominerals and their biomimetics does not necessarily follow classical crystallization routes, and leaves a characteristic nanotextural imprint which may help to disclose their origins and formation mechanisms. Here we present a general overview of the current theories and models of nonclassical crystallization and their applicability for the advance of our current understanding of biomineralization and biomimetic mineralization. We pay particular attention to the link between nonclassical crystallization routes and the resulting nanogranular textures of biomimetic CaCO3 mineral structures. After a general introductory section, we present an overview of classical nucleation and crystal growth theories and their limitations. Then, we introduce the Ostwald's step rule as a general framework to explain nonclassical crystallization. Subsequently, we describe nonclassical crystallization routes involving stable prenucleation clusters, dense liquid and solid amorphous precursor phases, as well as current nonclassical crystal growth models. The latter include oriented attachment, mesocrystallization and the new model based on the colloidal growth of crystals via attachment of amorphous nanoparticles. Biomimetic examples of nanostructured CaCO3 minerals formed via these nonclassical routes are presented which help us to show that colloid-mediated crystal growth can be regarded as a wide-spread growth mechanism. Implications of these observations for the advance in the current understanding on the formation of biomimetic materials and biominerals are finally outlined.


Assuntos
Coloides , Minerais/metabolismo , Nanopartículas/química , Biomimética/métodos , Carbonato de Cálcio/metabolismo , Cristalização , Minerais/química , Nanopartículas/metabolismo
18.
J Struct Biol ; 196(2): 244-259, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27456365

RESUMO

A distinct nanogranular fine structure is shared by a wealth of biominerals from several species, classes and taxa. This nanoscopic organization affects the properties and behavior of the biogenic ceramic material and confers on them attributes that are essential to their function. We present a set of structure-relationship properties that are rooted in the nanogranular organization and we propose that they rest on a common pathway of formation, a colloid-driven and hence nonclassical mode of crystallization. With this common modus operandi, we reveal the most fundamental and wide spread process-structure-property relationship in biominerals. With the recent increase in our understanding of nonclassical crystallization in vitro and in vivo, this significant process-structure-property relationship will serve as a source for new design approaches of bio-inspired materials.


Assuntos
Minerais/metabolismo , Nanopartículas/química , Animais , Calcificação Fisiológica , Coloides , Cristalização , Minerais/química
19.
Hum Mol Genet ; 23(10): 2511-26, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24412933

RESUMO

Ocular coloboma is a congenital defect resulting from failure of normal closure of the optic fissure during embryonic eye development. This birth defect causes childhood blindness worldwide, yet the genetic etiology is poorly understood. Here, we identified a novel homozygous mutation in the SALL2 gene in members of a consanguineous family affected with non-syndromic ocular coloboma variably affecting the iris and retina. This mutation, c.85G>T, introduces a premature termination codon (p.Glu29*) predicted to truncate the SALL2 protein so that it lacks three clusters of zinc-finger motifs that are essential for DNA-binding activity. This discovery identifies SALL2 as the third member of the Drosophila homeotic Spalt-like family of developmental transcription factor genes implicated in human disease. SALL2 is expressed in the developing human retina at the time of, and subsequent to, optic fissure closure. Analysis of Sall2-deficient mouse embryos revealed delayed apposition of the optic fissure margins and the persistence of an anterior retinal coloboma phenotype after birth. Sall2-deficient embryos displayed correct posterior closure toward the optic nerve head, and upon contact of the fissure margins, dissolution of the basal lamina occurred and PAX2, known to be critical for this process, was expressed normally. Anterior closure was disrupted with the fissure margins failing to meet, or in some cases misaligning leading to a retinal lesion. These observations demonstrate, for the first time, a role for SALL2 in eye morphogenesis and that loss of function of the gene causes ocular coloboma in humans and mice.


Assuntos
Códon sem Sentido , Coloboma/genética , Fatores de Transcrição/genética , Adolescente , Animais , Criança , Consanguinidade , Análise Mutacional de DNA , Proteínas de Ligação a DNA , Olho/embriologia , Olho/patologia , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Feminino , Expressão Gênica , Genes Recessivos , Estudos de Associação Genética , Predisposição Genética para Doença , Células HEK293 , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Homozigoto , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/metabolismo , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/genética , Fatores de Transcrição Box Pareados/metabolismo , Linhagem , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
20.
Ther Umsch ; 72(4): 247-53, 2015 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-25791048

RESUMO

The issue of the capacity of judgement or the lack thereof and the validity of legal actions performed in such conditions will become more and more important considering the longer life expectancy and the increasing number of people with diseases like dementia. This paper will discuss the capacity of judgement from a legal point of view. According to article 16 of the swiss civil code a person is capable of judgement within the meaning of the law if he or she does not lack the capacity to act rationally by virtue of being under age or because of a mental disability, mental disorder, intoxication or similar circumstances. Therefore, the incapacity of judgement requires the existence of one of the aforementioned conditions (objective aspect) which have to result in the lack of capacity to act rationally (subjective aspect). The capacity of judgement is relative and must always be evaluated within a given context, i. e. the capacity of judgement has to be confirmed or refuted for a specific transaction at a specific time. By law, the capacity of judgement is assumed (statutory presumption) and the opposite has to be proven. As part of a notarial procedure the capacity of judgement has to be verified by the notary public, although only in a brief and limited manner. If the capacity of judgement is disputed, only the competent civil judge has the power to render a legally binding judgement.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/psicologia , Julgamento , Competência Mental/legislação & jurisprudência , Idoso , Humanos , Suíça
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA