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1.
BMC Psychiatry ; 22(1): 486, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858846

RESUMO

BACKGROUND: The COVID-19 pandemic that began in late 2019 is caused by infection with the severe acute respiratory syndrome coronavirus-2. Since that time, many neuropsychiatric sequelae including psychosis, neurocognitive disorders, and mood disorders have been observed. The mechanism underlying these effects are currently unknown, however several mechanisms have been proposed. CASE PRESENTATION: A 47-year-old woman with past medical history including hypertension and premenstrual syndrome but no psychiatric history presented to the psychiatric hospital with new onset mania. She had developed symptoms of COVID-19 and was later diagnosed with COVID pneumonia. During quarantine, she reported high levels of stress, grief, and anxiety. Seventeen days into her illness, she developed altered mental status, sleeplessness, elevated mood, talkativeness, and preoccupations. Her spouse was concerned for her safety and contacted emergency medical services who brought her to the psychiatric hospital. She had not slept for five days prior to her arrival and exhibited flight of ideas, talkativeness, and grandiose ideas. She reported a family history of bipolar disorder but no past manic or depressive episodes. She was diagnosed with acute mania and stabilized using antipsychotics, a mood stabilizer, and a short course of a benzodiazepine. Many of her symptoms improved, including her elevated mood, increased activity level, and flight of ideas though she continued to have decreased need for sleep as her benzodiazepine was tapered. She and her partner were agreeable to transitioning to outpatient care after her mood stabilized. CONCLUSIONS: This report emphasizes the link between COVID-19 and neuropsychiatric symptoms. Acute mania has no recognized association with COVID-19, but similar presentations have been reported. The patient's age and time to onset of psychiatric symptoms is consistent with previous reports. Given the growing body of evidence, this association warrants further investigation. Severe acute respiratory syndrome coronavirus-2 causes systemic inflammation and has been shown to be neurotropic. In addition, patients undergoing quarantine experience anxiety related to the disease in addition to social isolation. Psychiatric practitioners should be aware of these effects and advocate for psychiatric evaluation following COVID-19 infection. Understanding the sequelae of infectious disease is crucial for responding to future pandemics.


Assuntos
Antipsicóticos , Transtorno Bipolar , COVID-19 , Antipsicóticos/uso terapêutico , Benzodiazepinas/uso terapêutico , Transtorno Bipolar/complicações , Transtorno Bipolar/diagnóstico , COVID-19/complicações , Feminino , Humanos , Mania , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2
2.
BMC Bioinformatics ; 19(1): 28, 2018 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-29385983

RESUMO

BACKGROUND: The clinical sequencing of cancer genomes to personalize therapy is becoming routine across the world. However, concerns over patient re-identification from these data lead to questions about how tightly access should be controlled. It is not thought to be possible to re-identify patients from somatic variant data. However, somatic variant detection pipelines can mistakenly identify germline variants as somatic ones, a process called "germline leakage". The rate of germline leakage across different somatic variant detection pipelines is not well-understood, and it is uncertain whether or not somatic variant calls should be considered re-identifiable. To fill this gap, we quantified germline leakage across 259 sets of whole-genome somatic single nucleotide variant (SNVs) predictions made by 21 teams as part of the ICGC-TCGA DREAM Somatic Mutation Calling Challenge. RESULTS: The median somatic SNV prediction set contained 4325 somatic SNVs and leaked one germline polymorphism. The level of germline leakage was inversely correlated with somatic SNV prediction accuracy and positively correlated with the amount of infiltrating normal cells. The specific germline variants leaked differed by tumour and algorithm. To aid in quantitation and correction of leakage, we created a tool, called GermlineFilter, for use in public-facing somatic SNV databases. CONCLUSIONS: The potential for patient re-identification from leaked germline variants in somatic SNV predictions has led to divergent open data access policies, based on different assessments of the risks. Indeed, a single, well-publicized re-identification event could reshape public perceptions of the values of genomic data sharing. We find that modern somatic SNV prediction pipelines have low germline-leakage rates, which can be further reduced, especially for cloud-sharing, using pre-filtering software.


Assuntos
Genoma Humano , Células Germinativas/metabolismo , Polimorfismo de Nucleotídeo Único , Algoritmos , Humanos , Internet , Neoplasias/genética , Neoplasias/patologia , Interface Usuário-Computador , Sequenciamento Completo do Genoma
3.
Nat Methods ; 12(7): 623-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25984700

RESUMO

The detection of somatic mutations from cancer genome sequences is key to understanding the genetic basis of disease progression, patient survival and response to therapy. Benchmarking is needed for tool assessment and improvement but is complicated by a lack of gold standards, by extensive resource requirements and by difficulties in sharing personal genomic information. To resolve these issues, we launched the ICGC-TCGA DREAM Somatic Mutation Calling Challenge, a crowdsourced benchmark of somatic mutation detection algorithms. Here we report the BAMSurgeon tool for simulating cancer genomes and the results of 248 analyses of three in silico tumors created with it. Different algorithms exhibit characteristic error profiles, and, intriguingly, false positives show a trinucleotide profile very similar to one found in human tumors. Although the three simulated tumors differ in sequence contamination (deviation from normal cell sequence) and in subclonality, an ensemble of pipelines outperforms the best individual pipeline in all cases. BAMSurgeon is available at https://github.com/adamewing/bamsurgeon/.


Assuntos
Benchmarking , Crowdsourcing , Genoma , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Algoritmos , Humanos
4.
Lancet Oncol ; 18(1): 132-142, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864015

RESUMO

BACKGROUND: Improvements to prognostic models in metastatic castration-resistant prostate cancer have the potential to augment clinical trial design and guide treatment strategies. In partnership with Project Data Sphere, a not-for-profit initiative allowing data from cancer clinical trials to be shared broadly with researchers, we designed an open-data, crowdsourced, DREAM (Dialogue for Reverse Engineering Assessments and Methods) challenge to not only identify a better prognostic model for prediction of survival in patients with metastatic castration-resistant prostate cancer but also engage a community of international data scientists to study this disease. METHODS: Data from the comparator arms of four phase 3 clinical trials in first-line metastatic castration-resistant prostate cancer were obtained from Project Data Sphere, comprising 476 patients treated with docetaxel and prednisone from the ASCENT2 trial, 526 patients treated with docetaxel, prednisone, and placebo in the MAINSAIL trial, 598 patients treated with docetaxel, prednisone or prednisolone, and placebo in the VENICE trial, and 470 patients treated with docetaxel and placebo in the ENTHUSE 33 trial. Datasets consisting of more than 150 clinical variables were curated centrally, including demographics, laboratory values, medical history, lesion sites, and previous treatments. Data from ASCENT2, MAINSAIL, and VENICE were released publicly to be used as training data to predict the outcome of interest-namely, overall survival. Clinical data were also released for ENTHUSE 33, but data for outcome variables (overall survival and event status) were hidden from the challenge participants so that ENTHUSE 33 could be used for independent validation. Methods were evaluated using the integrated time-dependent area under the curve (iAUC). The reference model, based on eight clinical variables and a penalised Cox proportional-hazards model, was used to compare method performance. Further validation was done using data from a fifth trial-ENTHUSE M1-in which 266 patients with metastatic castration-resistant prostate cancer were treated with placebo alone. FINDINGS: 50 independent methods were developed to predict overall survival and were evaluated through the DREAM challenge. The top performer was based on an ensemble of penalised Cox regression models (ePCR), which uniquely identified predictive interaction effects with immune biomarkers and markers of hepatic and renal function. Overall, ePCR outperformed all other methods (iAUC 0·791; Bayes factor >5) and surpassed the reference model (iAUC 0·743; Bayes factor >20). Both the ePCR model and reference models stratified patients in the ENTHUSE 33 trial into high-risk and low-risk groups with significantly different overall survival (ePCR: hazard ratio 3·32, 95% CI 2·39-4·62, p<0·0001; reference model: 2·56, 1·85-3·53, p<0·0001). The new model was validated further on the ENTHUSE M1 cohort with similarly high performance (iAUC 0·768). Meta-analysis across all methods confirmed previously identified predictive clinical variables and revealed aspartate aminotransferase as an important, albeit previously under-reported, prognostic biomarker. INTERPRETATION: Novel prognostic factors were delineated, and the assessment of 50 methods developed by independent international teams establishes a benchmark for development of methods in the future. The results of this effort show that data-sharing, when combined with a crowdsourced challenge, is a robust and powerful framework to develop new prognostic models in advanced prostate cancer. FUNDING: Sanofi US Services, Project Data Sphere.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Modelos Estatísticos , Nomogramas , Neoplasias de Próstata Resistentes à Castração/mortalidade , Adolescente , Adulto , Idoso , Teorema de Bayes , Crowdsourcing , Docetaxel , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Prognóstico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/secundário , Taxa de Sobrevida , Taxoides/administração & dosagem , Adulto Jovem
5.
Nucleic Acids Res ; 42(Database issue): D184-90, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24271392

RESUMO

The ease of generating high-throughput data has enabled investigations into organismal complexity at the systems level through the inference of networks of interactions among the various cellular components (genes, RNAs, proteins and metabolites). The wider scientific community, however, currently has limited access to tools for network inference, visualization and analysis because these tasks often require advanced computational knowledge and expensive computing resources. We have designed the network portal (http://networks.systemsbiology.net) to serve as a modular database for the integration of user uploaded and public data, with inference algorithms and tools for the storage, visualization and analysis of biological networks. The portal is fully integrated into the Gaggle framework to seamlessly exchange data with desktop and web applications and to allow the user to create, save and modify workspaces, and it includes social networking capabilities for collaborative projects. While the current release of the database contains networks for 13 prokaryotic organisms from diverse phylogenetic clades (4678 co-regulated gene modules, 3466 regulators and 9291 cis-regulatory motifs), it will be rapidly populated with prokaryotic and eukaryotic organisms as relevant data become available in public repositories and through user input. The modular architecture, simple data formats and open API support community development of the portal.


Assuntos
Bases de Dados Genéticas , Redes Reguladoras de Genes , Algoritmos , Archaea/genética , Archaea/metabolismo , Bactérias/genética , Bactérias/metabolismo , Gráficos por Computador , Perfilação da Expressão Gênica , Internet , Motivos de Nucleotídeos , Elementos Reguladores de Transcrição , Software , Integração de Sistemas , Fatores de Transcrição/metabolismo
6.
Genome Res ; 21(11): 1892-904, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21750103

RESUMO

Assembly of genes into operons is generally viewed as an important process during the continual adaptation of microbes to changing environmental challenges. However, the genome reorganization events that drive this process are also the roots of instability for existing operons. We have determined that there exists a statistically significant trend that correlates the proportion of genes encoded in operons in archaea to their phylogenetic lineage. We have further characterized how microbes deal with operon instability by mapping and comparing transcriptome architectures of four phylogenetically diverse extremophiles that span the range of operon stabilities observed across archaeal lineages: a photoheterotrophic halophile (Halobacterium salinarum NRC-1), a hydrogenotrophic methanogen (Methanococcus maripaludis S2), an acidophilic and aerobic thermophile (Sulfolobus solfataricus P2), and an anaerobic hyperthermophile (Pyrococcus furiosus DSM 3638). We demonstrate how the evolution of transcriptional elements (promoters and terminators) generates new operons, restores the coordinated regulation of translocated, inverted, and newly acquired genes, and introduces completely novel regulation for even some of the most conserved operonic genes such as those encoding subunits of the ribosome. The inverse correlation (r=-0.92) between the proportion of operons with such internally located transcriptional elements and the fraction of conserved operons in each of the four archaea reveals an unprecedented view into varying stages of operon evolution. Importantly, our integrated analysis has revealed that organisms adapted to higher growth temperatures have lower tolerance for genome reorganization events that disrupt operon structures.


Assuntos
Evolução Molecular , Genoma Arqueal , Transcriptoma , Adenosina Trifosfatases/genética , Archaea/classificação , Archaea/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica em Archaea , Genes Arqueais , Óperon , Filogenia , Regiões Promotoras Genéticas , Biossíntese de Proteínas/genética , Transporte de RNA , Transcrição Gênica , Ativação Transcricional
7.
Appl Environ Microbiol ; 79(20): 6407-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23934496

RESUMO

Free-living protozoa play an important role in the ecology and epidemiology of human-pathogenic bacteria. In the present study, the interaction between Yersinia enterocolitica, an important food-borne pathogen, and the free-living amoeba Acanthamoeba castellanii was studied. Several cocultivation assays were set up to assess the resistance of Y. enterocolitica to A. castellanii predation and the impact of environmental factors and bacterial strain-specific characteristics. Results showed that all Y. enterocolitica strains persist in association with A. castellanii for at least 14 days, and associations with A. castellanii enhanced survival of Yersinia under nutrient-rich conditions at 25°C and under nutrient-poor conditions at 37°C. Amoebae cultivated in the supernatant of one Yersinia strain showed temperature- and time-dependent permeabilization. Intraprotozoan survival of Y. enterocolitica depended on nutrient availability and temperature, with up to 2.8 log CFU/ml bacteria displaying intracellular survival at 7°C for at least 4 days in nutrient-rich medium. Transmission electron microscopy was performed to locate the Yersinia cells inside the amoebae. As Yersinia and Acanthamoeba share similar ecological niches, this interaction identifies a role of free-living protozoa in the ecology and epidemiology of Y. enterocolitica.


Assuntos
Acanthamoeba castellanii/fisiologia , Interações Microbianas , Viabilidade Microbiana , Yersinia enterocolitica/fisiologia , Microscopia Eletrônica , Temperatura
8.
Nucleic Acids Res ; 39(Web Server issue): W125-31, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21602264

RESUMO

Transcriptome profiling studies have produced staggering numbers of gene co-expression signatures for a variety of biological systems. A significant fraction of these signatures will be partially or fully explained by miRNA-mediated targeted transcript degradation. miRvestigator takes as input lists of co-expressed genes from Caenorhabditis elegans, Drosophila melanogaster, G. gallus, Homo sapiens, Mus musculus or Rattus norvegicus and identifies the specific miRNAs that are likely to bind to 3' un-translated region (UTR) sequences to mediate the observed co-regulation. The novelty of our approach is the miRvestigator hidden Markov model (HMM) algorithm which systematically computes a similarity P-value for each unique miRNA seed sequence from the miRNA database miRBase to an overrepresented sequence motif identified within the 3'-UTR of the query genes. We have made this miRNA discovery tool accessible to the community by integrating our HMM algorithm with a proven algorithm for de novo discovery of miRNA seed sequences and wrapping these algorithms into a user-friendly interface. Additionally, the miRvestigator web server also produces a list of putative miRNA binding sites within 3'-UTRs of the query transcripts to facilitate the design of validation experiments. The miRvestigator is freely available at http://mirvestigator.systemsbiology.net.


Assuntos
Regiões 3' não Traduzidas , Regulação da Expressão Gênica , MicroRNAs/química , MicroRNAs/metabolismo , Software , Animais , Perfilação da Expressão Gênica , Humanos , Internet , Camundongos , Ratos , Análise de Sequência de RNA
9.
Mol Syst Biol ; 7: 554, 2011 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-22108796

RESUMO

Numerous lineage-specific expansions of the transcription factor B (TFB) family in archaea suggests an important role for expanded TFBs in encoding environment-specific gene regulatory programs. Given the characteristics of hypersaline lakes, the unusually large numbers of TFBs in halophilic archaea further suggests that they might be especially important in rapid adaptation to the challenges of a dynamically changing environment. Motivated by these observations, we have investigated the implications of TFB expansions by correlating sequence variations, regulation, and physical interactions of all seven TFBs in Halobacterium salinarum NRC-1 to their fitness landscapes, functional hierarchies, and genetic interactions across 2488 experiments covering combinatorial variations in salt, pH, temperature, and Cu stress. This systems analysis has revealed an elegant scheme in which completely novel fitness landscapes are generated by gene conversion events that introduce subtle changes to the regulation or physical interactions of duplicated TFBs. Based on these insights, we have introduced a synthetically redesigned TFB and altered the regulation of existing TFBs to illustrate how archaea can rapidly generate novel phenotypes by simply reprogramming their TFB regulatory network.


Assuntos
Adaptação Fisiológica/genética , Proteínas Arqueais/genética , Halobacterium salinarum/metabolismo , Fator de Transcrição TFIIB/genética , Fator de Transcrição TFIIB/metabolismo , Proteínas Arqueais/metabolismo , Evolução Molecular , Regulação da Expressão Gênica em Archaea , Halobacterium salinarum/genética , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tolerância ao Sal , Estresse Fisiológico
10.
J Environ Radioact ; 255: 106968, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36148707

RESUMO

In 2015 and 2016, atmospheric transport modeling challenges were conducted in the context of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification, however, with a more limited scope with respect to emission inventories, simulation period and number of relevant samples (i.e., those above the Minimum Detectable Concentration (MDC)) involved. Therefore, a more comprehensive atmospheric transport modeling challenge was organized in 2019. Stack release data of Xe-133 were provided by the Institut National des Radioéléments/IRE (Belgium) and the Canadian Nuclear Laboratories/CNL (Canada) and accounted for in the simulations over a three (mandatory) or six (optional) months period. Best estimate emissions of additional facilities (radiopharmaceutical production and nuclear research facilities, commercial reactors or relevant research reactors) of the Northern Hemisphere were included as well. Model results were compared with observed atmospheric activity concentrations at four International Monitoring System (IMS) stations located in Europe and North America with overall considerable influence of IRE and/or CNL emissions for evaluation of the participants' runs. Participants were prompted to work with controlled and harmonized model set-ups to make runs more comparable, but also to increase diversity. It was found that using the stack emissions of IRE and CNL with daily resolution does not lead to better results than disaggregating annual emissions of these two facilities taken from the literature if an overall score for all stations covering all valid observed samples is considered. A moderate benefit of roughly 10% is visible in statistical scores for samples influenced by IRE and/or CNL to at least 50% and there can be considerable benefit for individual samples. Effects of transport errors, not properly characterized remaining emitters and long IMS sampling times (12-24 h) undoubtedly are in contrast to and reduce the benefit of high-quality IRE and CNL stack data. Complementary best estimates for remaining emitters push the scores up by 18% compared to just considering IRE and CNL emissions alone. Despite the efforts undertaken the full multi-model ensemble built is highly redundant. An ensemble based on a few arbitrary runs is sufficient to model the Xe-133 background at the stations investigated. The effective ensemble size is below five. An optimized ensemble at each station has on average slightly higher skill compared to the full ensemble. However, the improvement (maximum of 20% and minimum of 3% in RMSE) in skill is likely being too small for being exploited for an independent period.


Assuntos
Poluentes Radioativos do Ar , Monitoramento de Radiação , Humanos , Radioisótopos de Xenônio/análise , Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/métodos , Canadá , Cooperação Internacional
11.
J Anim Physiol Anim Nutr (Berl) ; 95(6): 701-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21114690

RESUMO

The aim of this study was to examine whether and to what extent the supplementation of feed with a coated or non-coated mixture of fatty acids (caprylic and capric acid) affects broiler chickens experimentally infected with Campylobacter jejuni. The study was carried out using 48 chickens divided into four experimental groups. Throughout the whole rearing period (1-42 days), the chickens were fed a diet supplemented with 0.25% caprylic and capric acid (1:1), coated or non-coated. At the age of 14 and 28 days, chickens were orally challenged with C. jejuni. At regular time intervals post-inoculation, the shedding of C. jejuni was assayed using quantitative real-time PCR. Both supplements significantly decreased faecal C. jejuni counts by 1.2-4.1 log(10) CFU/g 4 days post-inoculation; after this time period, the effect of medium-chain fatty acids (MCFA) was less pronounced or absent. Campylobacter jejuni counts in excreta samples were significantly lower in chickens fed coated MCFA than in those fed non-coated MCFA. No effect of MCFA on feed intake or growth of chickens was observed. In conclusion, (i) MCFA are active against C. jejuni and (ii) the encapsulation enhanced the efficacy of the acids. These results allow the recommendation of using MCFA as feed additives in chickens, preferably 2-3 days before slaughter.


Assuntos
Infecções por Campylobacter/veterinária , Galinhas , Ácidos Graxos/química , Ácidos Graxos/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Infecções por Campylobacter/prevenção & controle , Campylobacter jejuni , Dieta/veterinária , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Fezes/microbiologia , Masculino , Doenças das Aves Domésticas/microbiologia
12.
BMC Bioinformatics ; 11: 382, 2010 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-20642854

RESUMO

BACKGROUND: High-density tiling arrays and new sequencing technologies are generating rapidly increasing volumes of transcriptome and protein-DNA interaction data. Visualization and exploration of this data is critical to understanding the regulatory logic encoded in the genome by which the cell dynamically affects its physiology and interacts with its environment. RESULTS: The Gaggle Genome Browser is a cross-platform desktop program for interactively visualizing high-throughput data in the context of the genome. Important features include dynamic panning and zooming, keyword search and open interoperability through the Gaggle framework. Users may bookmark locations on the genome with descriptive annotations and share these bookmarks with other users. The program handles large sets of user-generated data using an in-process database and leverages the facilities of SQL and the R environment for importing and manipulating data.A key aspect of the Gaggle Genome Browser is interoperability. By connecting to the Gaggle framework, the genome browser joins a suite of interconnected bioinformatics tools for analysis and visualization with connectivity to major public repositories of sequences, interactions and pathways. To this flexible environment for exploring and combining data, the Gaggle Genome Browser adds the ability to visualize diverse types of data in relation to its coordinates on the genome. CONCLUSIONS: Genomic coordinates function as a common key by which disparate biological data types can be related to one another. In the Gaggle Genome Browser, heterogeneous data are joined by their location on the genome to create information-rich visualizations yielding insight into genome organization, transcription and its regulation and, ultimately, a better understanding of the mechanisms that enable the cell to dynamically respond to its environment.


Assuntos
Genômica/métodos , Biologia de Sistemas/métodos , Bacillus anthracis/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genoma Arqueal , Halobacterium salinarum/genética , Software
13.
Mol Syst Biol ; 5: 285, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19536208

RESUMO

Despite the knowledge of complex prokaryotic-transcription mechanisms, generalized rules, such as the simplified organization of genes into operons with well-defined promoters and terminators, have had a significant role in systems analysis of regulatory logic in both bacteria and archaea. Here, we have investigated the prevalence of alternate regulatory mechanisms through genome-wide characterization of transcript structures of approximately 64% of all genes, including putative non-coding RNAs in Halobacterium salinarum NRC-1. Our integrative analysis of transcriptome dynamics and protein-DNA interaction data sets showed widespread environment-dependent modulation of operon architectures, transcription initiation and termination inside coding sequences, and extensive overlap in 3' ends of transcripts for many convergently transcribed genes. A significant fraction of these alternate transcriptional events correlate to binding locations of 11 transcription factors and regulators (TFs) inside operons and annotated genes-events usually considered spurious or non-functional. Using experimental validation, we illustrate the prevalence of overlapping genomic signals in archaeal transcription, casting doubt on the general perception of rigid boundaries between coding sequences and regulatory elements.


Assuntos
Genes Arqueais , Óperon , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Simulação por Computador , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Genoma Bacteriano , Halobacterium salinarum/genética , Halobacterium salinarum/fisiologia , Modelos Genéticos , Método de Monte Carlo , RNA/genética , Reprodutibilidade dos Testes , Fatores de Transcrição/metabolismo , Transcrição Gênica
14.
J Appl Microbiol ; 109(5): 1566-78, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20569273

RESUMO

AIMS: Evaluation of a sampling method to recover free-living protozoa (FLP) from plastic surfaces. Application of the method on different areas inside domestic refrigerators. METHODS AND RESULTS: Plastic coupons seeded with representatives of FLP were swabbed with cotton wools. The recovery efficiency was the highest for Chilomonas paramecium, followed by Tetrahymena pyriformis and the lowest for Acanthamoeba polyphaga. From 43 refrigerators, 19 and 26 were considered FLP positive when sample cultures were incubated at 7°C and 20°C, respectively. The number of FLP-positive cultures was the highest in samples taken from vegetable trays followed by discharge gutters, whereas interior walls were rarely FLP positive. Higher numbers of taxa were observed in enrichment cultures incubated at 20°C instead of 7°C. The combination of microscopy and denaturing gradient gel electrophoresis revealed that discharge gutters occasionally were contaminated with a persistent protozoan population of flagellates (Cercozoa) and amoebae (Tubulinea). The FLP-positive status of refrigerator surfaces was correlated with a high aerobic plate count. CONCLUSIONS: The cotton wool sampling method is useful to sample FLP from plastic surfaces. FLP are part of the microbial communities in domestic refrigerators. SIGNIFICANCE AND IMPACT OF THE STUDY: Knowledge on the occurrence of FLP in food-related indoor environments is scarce. For the first time, a high protozoan diversity in domestic refrigerators is described.


Assuntos
Acanthamoeba/fisiologia , Biodiversidade , Cilióforos/fisiologia , Criptófitas/fisiologia , Microbiologia Ambiental , Técnicas Microbiológicas/métodos , Refrigeração/instrumentação , Animais , Fibra de Algodão , Eletroforese em Gel de Gradiente Desnaturante , Técnicas Microbiológicas/instrumentação , Temperatura
15.
J Cell Biol ; 106(3): 585-96, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3126192

RESUMO

A cDNA clone encoding a portion of Drosophila nuclear lamins Dm1 and Dm2 has been identified by screening a lambda-gt11 cDNA expression library using Drosophila lamin-specific monoclonal antibodies. Two different developmentally regulated mRNA species were identified by Northern blot analysis using the initial cDNA as a probe, and full-length cDNA clones, apparently corresponding to each message, have been isolated. In vitro transcription of both full-length cDNA clones in a pT7 transcription vector followed by in vitro translation in wheat germ lysate suggests that both clones encode lamin Dm0, the polypeptide precursor of lamins Dm1 and Dm2. Nucleotide sequence analyses confirm the impression that both cDNA clones code for the identical polypeptide, which is highly homologous with human lamins A and C as well as with mammalian intermediate filament proteins. The two clones differ in their 3'-untranslated regions. In situ hybridization of lamin cDNA clones to Drosophila polytene chromosomes shows only a single locus of hybridization at or near position 25F on the left arm of chromosome 2. Southern blot analyses of genomic DNA are consistent with the notion that a single or only a few highly similar genes encoding Drosophila nuclear lamin Dm0 exist in the genome.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Genes , Proteínas Nucleares/genética , Precursores de Proteínas/genética , RNA Mensageiro/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA/genética , Feminino , Imunoensaio , Laminas , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Biossíntese de Proteínas , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
16.
Science ; 272(5268): 1668-71, 1996 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-8658145

RESUMO

The basal cell nevus syndrome (BCNS) is characterized by developmental abnormalities and by the postnatal occurrence of cancers, especially basal cell carcinomas (BCCs), the most common human cancer. Heritable mutations in BCNS patients and a somatic mutation in a sporadic BCC were identified in a human homolog of the Drosophila patched (ptc) gene. The ptc gene encodes a transmembrane protein that in Drosophila acts in opposition to the Hedgehog signaling protein, controlling cell fates, patterning, and growth in numerous tissues. The human PTC gene appears to be crucial for proper embryonic development and for tumor suppression.


Assuntos
Síndrome do Nevo Basocelular/genética , Proteínas de Drosophila , Genes Supressores de Tumor , Proteínas de Membrana/genética , Adulto , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA de Neoplasias , Drosophila , Feminino , Mutação da Fase de Leitura , Humanos , Hormônios de Inseto/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Receptores Patched , Receptor Patched-1 , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Conformação Proteica , Receptores de Superfície Celular
17.
Genome Biol ; 19(1): 188, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30400818

RESUMO

BACKGROUND: The phenotypes of cancer cells are driven in part by somatic structural variants. Structural variants can initiate tumors, enhance their aggressiveness, and provide unique therapeutic opportunities. Whole-genome sequencing of tumors can allow exhaustive identification of the specific structural variants present in an individual cancer, facilitating both clinical diagnostics and the discovery of novel mutagenic mechanisms. A plethora of somatic structural variant detection algorithms have been created to enable these discoveries; however, there are no systematic benchmarks of them. Rigorous performance evaluation of somatic structural variant detection methods has been challenged by the lack of gold standards, extensive resource requirements, and difficulties arising from the need to share personal genomic information. RESULTS: To facilitate structural variant detection algorithm evaluations, we create a robust simulation framework for somatic structural variants by extending the BAMSurgeon algorithm. We then organize and enable a crowdsourced benchmarking within the ICGC-TCGA DREAM Somatic Mutation Calling Challenge (SMC-DNA). We report here the results of structural variant benchmarking on three different tumors, comprising 204 submissions from 15 teams. In addition to ranking methods, we identify characteristic error profiles of individual algorithms and general trends across them. Surprisingly, we find that ensembles of analysis pipelines do not always outperform the best individual method, indicating a need for new ways to aggregate somatic structural variant detection approaches. CONCLUSIONS: The synthetic tumors and somatic structural variant detection leaderboards remain available as a community benchmarking resource, and BAMSurgeon is available at https://github.com/adamewing/bamsurgeon .


Assuntos
Benchmarking , Simulação por Computador , Crowdsourcing , Variação Genética , Genoma Humano , Genômica/métodos , Neoplasias/genética , Algoritmos , Bases de Dados Genéticas , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Software
18.
BMC Bioinformatics ; 8: 456, 2007 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-18021453

RESUMO

BACKGROUND: Information resources on the World Wide Web play an indispensable role in modern biology. But integrating data from multiple sources is often encumbered by the need to reformat data files, convert between naming systems, or perform ongoing maintenance of local copies of public databases. Opportunities for new ways of combining and re-using data are arising as a result of the increasing use of web protocols to transmit structured data. RESULTS: The Firegoose, an extension to the Mozilla Firefox web browser, enables data transfer between web sites and desktop tools. As a component of the Gaggle integration framework, Firegoose can also exchange data with Cytoscape, the R statistical package, Multiexperiment Viewer (MeV), and several other popular desktop software tools. Firegoose adds the capability to easily use local data to query KEGG, EMBL STRING, DAVID, and other widely-used bioinformatics web sites. Query results from these web sites can be transferred to desktop tools for further analysis with a few clicks. Firegoose acquires data from the web by screen scraping, microformats, embedded XML, or web services. We define a microformat, which allows structured information compatible with the Gaggle to be embedded in HTML documents. We demonstrate the capabilities of this software by performing an analysis of the genes activated in the microbe Halobacterium salinarum NRC-1 in response to anaerobic environments. Starting with microarray data, we explore functions of differentially expressed genes by combining data from several public web resources and construct an integrated view of the cellular processes involved. CONCLUSION: The Firegoose incorporates Mozilla Firefox into the Gaggle environment and enables interactive sharing of data between diverse web resources and desktop software tools without maintaining local copies. Additional web sites can be incorporated easily into the framework using the scripting platform of the Firefox browser. Performing data integration in the browser allows the excellent search and navigation capabilities of the browser to be used in combination with powerful desktop tools.


Assuntos
Biologia Computacional , Internet/organização & administração , Design de Software , Interface Usuário-Computador , Apresentação de Dados , Bases de Dados Genéticas , Perfilação da Expressão Gênica/métodos , Halobacterium salinarum , Humanos , Hipermídia , Disseminação de Informação/métodos , Armazenamento e Recuperação da Informação/métodos , Análise de Sequência com Séries de Oligonucleotídeos , Integração de Sistemas
19.
J Environ Radioact ; 175-176: 135-148, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28544976

RESUMO

To investigate the transport of xenon emissions, the Provisional Technical Secretariat (PTS) operates an Atmospheric Transport Modelling (ATM) system based on the Lagrangian Particle Dispersion Model FLEXPART. The air mass trajectory ideally provides a "link" between a radionuclide release and a detection confirmed by radionuclide measurements. This paper investigates the long-range transport of Xe-133 emissions under convective and non-convective conditions, with special emphasis on evaluating the changes in the simulated activity concentration values due to the inclusion of the convective transport in the ATM simulations. For that purpose a series of 14 day forward simulations, with and without convective transport, released daily in the period from 1 January 2011 to 30 June 2013, were analysed. The release point was at the ANSTO facility in Australia. The simulated activity concentrations for the period January 2011 to February 2012 were calculated using the daily emission values provided by the ANSTO facility; outside the aforementioned period, the median daily emission value was used. In the simulations the analysed meteorological input data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF) were used with the spatial resolution of 0.5°. It was found that the long-range transport of Xe-133 emissions under convective conditions, where convection was included in the ATM simulation, led to a small decrease in the activity concentration, as compared to transport without convection. In special cases related to deep convection, the opposite effect was observed. Availability of both daily emission values and measured Xe-133 activity concentration values was an opportunity to validate the simulations. Based on the paired t-test, a 95% confidence interval for the true mean difference between simulations without convective transport and measurements was constructed. It was estimated that the overall uncertainty lies between 0.08 and 0.25 mBq/m3. The uncertainty for the simulations with the convective transport included is slighted shifted to the lower values and is in the range between 0.06 and 0.20 mBq/m3.


Assuntos
Poluentes Radioativos do Ar/análise , Monitoramento de Radiação , Radioisótopos de Xenônio/análise , Austrália , Modelos Teóricos , Compostos Radiofarmacêuticos/análise
20.
Bone Joint J ; 99-B(2): 184-191, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28148659

RESUMO

AIMS: The pelvis rotates in the sagittal plane during daily activities. These rotations have a direct effect on the functional orientation of the acetabulum. The aim of this study was to quantify changes in pelvic tilt between different functional positions. PATIENTS AND METHODS: Pre-operatively, pelvic tilt was measured in 1517 patients undergoing total hip arthroplasty (THA) in three functional positions - supine, standing and flexed seated (the moment when patients initiate rising from a seated position). Supine pelvic tilt was measured from CT scans, standing and flexed seated pelvic tilts were measured from standardised lateral radiographs. Anterior pelvic tilt was assigned a positive value. RESULTS: The mean pelvic tilt was 4.2° (-20.5° to 24.5°), -1.3° (-30.2° to 27.9°) and 0.6° (-42.0° to 41.3°) in the three positions, respectively. The mean sagittal pelvic rotation from supine to standing was -5.5° (-21.8° to 8.4°), from supine to flexed seated was -3.7° (-48.3° to 38.6°) and from standing to flexed seated was 1.8° (-51.8° to 39.5°). In 259 patients (17%), the extent of sagittal pelvic rotation could lead to functional malorientation of the acetabular component. Factoring in an intra-operative delivery error of ± 5° extends this risk to 51% of patients. CONCLUSION: Planning and measurement of the intended position of the acetabular component in the supine position may fail to predict clinically significant changes in its orientation during functional activities, as a consequence of individual pelvic kinematics. Optimal orientation is patient-specific and requires an evaluation of functional pelvic tilt pre-operatively. Cite this article: Bone Joint J 2017;99-B:184-91.


Assuntos
Acetábulo/fisiopatologia , Artroplastia de Quadril , Osteoartrite do Quadril/fisiopatologia , Ossos Pélvicos/diagnóstico por imagem , Postura/fisiologia , Acetábulo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/cirurgia , Ossos Pélvicos/fisiopatologia , Amplitude de Movimento Articular , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Adulto Jovem
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