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1.
Cell ; 153(3): 666-77, 2013 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-23622249

RESUMO

The analysis of exonic DNA from prostate cancers has identified recurrently mutated genes, but the spectrum of genome-wide alterations has not been profiled extensively in this disease. We sequenced the genomes of 57 prostate tumors and matched normal tissues to characterize somatic alterations and to study how they accumulate during oncogenesis and progression. By modeling the genesis of genomic rearrangements, we identified abundant DNA translocations and deletions that arise in a highly interdependent manner. This phenomenon, which we term "chromoplexy," frequently accounts for the dysregulation of prostate cancer genes and appears to disrupt multiple cancer genes coordinately. Our modeling suggests that chromoplexy may induce considerable genomic derangement over relatively few events in prostate cancer and other neoplasms, supporting a model of punctuated cancer evolution. By characterizing the clonal hierarchy of genomic lesions in prostate tumors, we charted a path of oncogenic events along which chromoplexy may drive prostate carcinogenesis.


Assuntos
Aberrações Cromossômicas , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Neoplasias da Próstata/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Estudos de Coortes , Estudo de Associação Genômica Ampla , Humanos , Masculino , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Neoplasias da Próstata/patologia
2.
Cell ; 150(2): 251-63, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22817889

RESUMO

Despite recent insights into melanoma genetics, systematic surveys for driver mutations are challenged by an abundance of passenger mutations caused by carcinogenic UV light exposure. We developed a permutation-based framework to address this challenge, employing mutation data from intronic sequences to control for passenger mutational load on a per gene basis. Analysis of large-scale melanoma exome data by this approach discovered six novel melanoma genes (PPP6C, RAC1, SNX31, TACC1, STK19, and ARID2), three of which-RAC1, PPP6C, and STK19-harbored recurrent and potentially targetable mutations. Integration with chromosomal copy number data contextualized the landscape of driver mutations, providing oncogenic insights in BRAF- and NRAS-driven melanoma as well as those without known NRAS/BRAF mutations. The landscape also clarified a mutational basis for RB and p53 pathway deregulation in this malignancy. Finally, the spectrum of driver mutations provided unequivocal genomic evidence for a direct mutagenic role of UV light in melanoma pathogenesis.


Assuntos
Estudo de Associação Genômica Ampla , Melanoma/genética , Mutagênese , Raios Ultravioleta , Sequência de Aminoácidos , Células Cultivadas , Exoma , Humanos , Melanócitos/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas B-raf/genética , Alinhamento de Sequência , Proteínas rac1 de Ligação ao GTP/genética
3.
BMC Med Educ ; 24(1): 758, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004704

RESUMO

BACKGROUND: Frequent attendance is a common issue for primary care health centres. The phenomenon affects the quality of care, increases doctors' workloads and can lead to burnout.This study presents the results of an educational intervention for primary care physicians, aimed at helping them to decrease the prevalence rate of excessive attendance by patients at their centres. METHODS: A training programme was carried out for 11 primary care doctors in Barcelona who had patient lists totalling 20,064 patients. The goal of the training was to provide the participating physicians with techniques to curb frequent attendance. Additionally, the programme sought to offer them strategies to prevent professional burnout and tools to better organize their everyday medical practice. The study used a quasi-experimental design for an evaluation of an educational intervention, featuring a pre-test assessment (before the training programme) and a post-test assessment (after the training programme), as well as comparison with a control group that did not undergo the training. The study assessed the effects of the programme on the rates of frequent attendance of patients served by the participating physicians. These rates were compared with those registered by the patients seen by the control group physicians over the same period. RESULTS: Among the group of physicians who received the training, the mean prevalence of patients who qualified as frequent attenders decreased from 22% prior to the training programme to 8% after completion of the programme. In other words, 14% of patients (2,809) limited the frequency of their visits to primary care physicians after their physicians had completed the training programme. Meanwhile, the study recorded an average decrease of 3.1 visits per year by the patients of the physicians who had undergone the training. Statistically significant differences between this group and the control group were observed. CONCLUSIONS: The educational intervention proved effective at helping primary care physicians to decrease their patients' rates of frequent attendance. It also contributes to the impact research of continuing education on doctors and their patients. We need to increase primary care spending from the current 14% to the 25%, to address this problem, among others.


Assuntos
Esgotamento Profissional , Médicos de Atenção Primária , Humanos , Masculino , Feminino , Esgotamento Profissional/prevenção & controle , Médicos de Atenção Primária/educação , Espanha , Pessoa de Meia-Idade , Adulto , Atenção Primária à Saúde , Educação Médica Continuada , Visita a Consultório Médico/estatística & dados numéricos
4.
Am J Obstet Gynecol ; 227(2): 277.e1-277.e16, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35351411

RESUMO

BACKGROUND: COVID-19 presents a spectrum of signs and symptoms in pregnant women that might resemble preeclampsia. Differentiation between severe COVID-19 and preeclampsia is difficult in some cases. OBJECTIVE: To study biomarkers of endothelial damage, coagulation, innate immune response, and angiogenesis in preeclampsia and COVID-19 in pregnancy in addition to in vitro alterations in endothelial cells exposed to sera from pregnant women with preeclampsia and COVID-19. STUDY DESIGN: Plasma and sera samples were obtained from pregnant women with COVID-19 infection classified into mild (n=10) or severe (n=9) and from women with normotensive pregnancies as controls (n=10) and patients with preeclampsia (n=13). A panel of plasmatic biomarkers was assessed, including vascular cell adhesion molecule-1, soluble tumor necrosis factor-receptor I, heparan sulfate, von Willebrand factor antigen (activity and multimeric pattern), α2-antiplasmin, C5b9, neutrophil extracellular traps, placental growth factor, soluble fms-like tyrosine kinase-1, and angiopoietin 2. In addition, microvascular endothelial cells were exposed to patients' sera, and changes in the cell expression of intercellular adhesion molecule 1 on cell membranes and von Willebrand factor release to the extracellular matrix were evaluated through immunofluorescence. Changes in inflammation cell signaling pathways were also assessed by of p38 mitogen-activated protein kinase phosphorylation. Statistical analysis included univariate and multivariate methods. RESULTS: Biomarker profiles of patients with mild COVID-19 were similar to those of controls. Both preeclampsia and severe COVID-19 showed significant alterations in most circulating biomarkers with distinctive profiles. Whereas severe COVID-19 exhibited higher concentrations of vascular cell adhesion molecule-1, soluble tumor necrosis factor-α receptor I, heparan sulfate, von Willebrand factor antigen, and neutrophil extracellular traps, with a significant reduction of placental growth factor compared with controls, preeclampsia presented a marked increase in vascular cell adhesion molecule-1 and soluble tumor necrosis factor-α receptor I (significantly increased compared with controls and patients with severe COVID-19), with a striking reduction in von Willebrand factor antigen, von Willebrand factor activity, and α2-antiplasmin. As expected, reduced placental growth factor, increased soluble fms-like tyrosine kinase-1 and angiopoietin 2, and a very high soluble fms-like tyrosine kinase-1 to placental growth factor ratio were also observed in preeclampsia. In addition, a significant increase in C5b9 and neutrophil extracellular traps was also detected in preeclampsia compared with controls. Principal component analysis demonstrated a clear separation between patients with preeclampsia and the other groups (first and second components explained 42.2% and 13.5% of the variance), mainly differentiated by variables related to von Willebrand factor, soluble tumor necrosis factor-receptor I, heparan sulfate, and soluble fms-like tyrosine kinase-1. Von Willebrand factor multimeric analysis revealed the absence of von Willebrand factor high-molecular-weight multimers in preeclampsia (similar profile to von Willebrand disease type 2A), whereas in healthy pregnancies and COVID-19 patients, von Willebrand factor multimeric pattern was normal. Sera from both preeclampsia and severe COVID-19 patients induced an overexpression of intercellular adhesion molecule 1 and von Willebrand factor in endothelial cells in culture compared with controls. However, the effect of preeclampsia was less pronounced than the that of severe COVID-19. Immunoblots of lysates from endothelial cells exposed to mild and severe COVID-19 and preeclampsia sera showed an increase in p38 mitogen-activated protein kinase phosphorylation. Patients with severe COVID-19 and preeclampsia were statistically different from controls, suggesting that both severe COVID-19 and preeclampsia sera can activate inflammatory signaling pathways. CONCLUSION: Although similar in in vitro endothelial dysfunction, preeclampsia and severe COVID-19 exhibit distinctive profiles of circulating biomarkers related to endothelial damage, coagulopathy, and angiogenic imbalance that could aid in the differential diagnosis of these entities.


Assuntos
Biomarcadores , COVID-19 , Pré-Eclâmpsia , Angiopoietina-2 , Biomarcadores/sangue , COVID-19/diagnóstico , Células Endoteliais , Feminino , Heparitina Sulfato , Humanos , Molécula 1 de Adesão Intercelular , Fator de Crescimento Placentário , Pré-Eclâmpsia/diagnóstico , Gravidez , Fator de Necrose Tumoral alfa , Molécula 1 de Adesão de Célula Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Proteínas Quinases p38 Ativadas por Mitógeno , Fator de von Willebrand
6.
Sensors (Basel) ; 20(11)2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32485791

RESUMO

Low-Power Wide-Area Network (LPWAN) is one of the enabling technologies of the Internet of Things (IoT), and focuses on providing long distance connectivity for a vast amount of smart devices. Currently, LoRa is one of the leading LPWAN solutions available for public use. In LPWANs, especially in LoRa, security is a major concern due to the resource constraints of the devices, the sensitivity level of the transmitted data, the large amount of connected devices, among other reasons. This paper studies the key management mechanism of LoRaWAN environments. A secure architecture for key management based on smart contracts and permissioned blockchain to enhance security and availability in LoRaWAN networks is proposed. To demonstrate the feasibility of the proposed blockchain-based LoRaWAN architecture, a working prototype has been created using open-source tools and commodity hardware. Performance analysis shows that the prototype presents similar execution time and latency values, when compared to a traditional system, especially for small and medium-sized LoRaWAN networks. We also discuss why the proposed solution can be used in environments with a large number of end-devices.

7.
Nature ; 499(7457): 214-218, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23770567

RESUMO

Major international projects are underway that are aimed at creating a comprehensive catalogue of all the genes responsible for the initiation and progression of cancer. These studies involve the sequencing of matched tumour-normal samples followed by mathematical analysis to identify those genes in which mutations occur more frequently than expected by random chance. Here we describe a fundamental problem with cancer genome studies: as the sample size increases, the list of putatively significant genes produced by current analytical methods burgeons into the hundreds. The list includes many implausible genes (such as those encoding olfactory receptors and the muscle protein titin), suggesting extensive false-positive findings that overshadow true driver events. We show that this problem stems largely from mutational heterogeneity and provide a novel analytical methodology, MutSigCV, for resolving the problem. We apply MutSigCV to exome sequences from 3,083 tumour-normal pairs and discover extraordinary variation in mutation frequency and spectrum within cancer types, which sheds light on mutational processes and disease aetiology, and in mutation frequency across the genome, which is strongly correlated with DNA replication timing and also with transcriptional activity. By incorporating mutational heterogeneity into the analyses, MutSigCV is able to eliminate most of the apparent artefactual findings and enable the identification of genes truly associated with cancer.


Assuntos
Heterogeneidade Genética , Mutação/genética , Neoplasias/genética , Oncogenes/genética , Artefatos , Período de Replicação do DNA , Exoma/genética , Reações Falso-Positivas , Expressão Gênica , Genoma Humano/genética , Humanos , Neoplasias Pulmonares/genética , Taxa de Mutação , Neoplasias/classificação , Neoplasias/patologia , Neoplasias de Células Escamosas/genética , Reprodutibilidade dos Testes , Tamanho da Amostra
8.
Nature ; 488(7409): 106-10, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22820256

RESUMO

Medulloblastomas are the most common malignant brain tumours in children. Identifying and understanding the genetic events that drive these tumours is critical for the development of more effective diagnostic, prognostic and therapeutic strategies. Recently, our group and others described distinct molecular subtypes of medulloblastoma on the basis of transcriptional and copy number profiles. Here we use whole-exome hybrid capture and deep sequencing to identify somatic mutations across the coding regions of 92 primary medulloblastoma/normal pairs. Overall, medulloblastomas have low mutation rates consistent with other paediatric tumours, with a median of 0.35 non-silent mutations per megabase. We identified twelve genes mutated at statistically significant frequencies, including previously known mutated genes in medulloblastoma such as CTNNB1, PTCH1, MLL2, SMARCA4 and TP53. Recurrent somatic mutations were newly identified in an RNA helicase gene, DDX3X, often concurrent with CTNNB1 mutations, and in the nuclear co-repressor (N-CoR) complex genes GPS2, BCOR and LDB1. We show that mutant DDX3X potentiates transactivation of a TCF promoter and enhances cell viability in combination with mutant, but not wild-type, ß-catenin. Together, our study reveals the alteration of WNT, hedgehog, histone methyltransferase and now N-CoR pathways across medulloblastomas and within specific subtypes of this disease, and nominates the RNA helicase DDX3X as a component of pathogenic ß-catenin signalling in medulloblastoma.


Assuntos
Neoplasias Cerebelares/genética , Exoma/genética , Genoma Humano/genética , Meduloblastoma/genética , Mutação/genética , Neoplasias Cerebelares/classificação , Criança , RNA Helicases DEAD-box/química , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , DNA Helicases/química , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Proteínas Hedgehog/metabolismo , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Meduloblastoma/classificação , Modelos Moleculares , Proteínas de Neoplasias/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Receptores Patched , Receptor Patched-1 , Regiões Promotoras Genéticas/genética , Estrutura Terciária de Proteína/genética , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular/genética , Proteínas Repressoras/genética , Transdução de Sinais , Fatores de Transcrição TCF/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Proteína Supressora de Tumor p53/genética , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
9.
Nature ; 485(7399): 502-6, 2012 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-22622578

RESUMO

Melanoma is notable for its metastatic propensity, lethality in the advanced setting and association with ultraviolet exposure early in life. To obtain a comprehensive genomic view of melanoma in humans, we sequenced the genomes of 25 metastatic melanomas and matched germline DNA. A wide range of point mutation rates was observed: lowest in melanomas whose primaries arose on non-ultraviolet-exposed hairless skin of the extremities (3 and 14 per megabase (Mb) of genome), intermediate in those originating from hair-bearing skin of the trunk (5-55 per Mb), and highest in a patient with a documented history of chronic sun exposure (111 per Mb). Analysis of whole-genome sequence data identified PREX2 (phosphatidylinositol-3,4,5-trisphosphate-dependent Rac exchange factor 2)--a PTEN-interacting protein and negative regulator of PTEN in breast cancer--as a significantly mutated gene with a mutation frequency of approximately 14% in an independent extension cohort of 107 human melanomas. PREX2 mutations are biologically relevant, as ectopic expression of mutant PREX2 accelerated tumour formation of immortalized human melanocytes in vivo. Thus, whole-genome sequencing of human melanoma tumours revealed genomic evidence of ultraviolet pathogenesis and discovered a new recurrently mutated gene in melanoma.


Assuntos
Genoma Humano/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Melanoma/genética , Mutação/genética , Luz Solar/efeitos adversos , Pontos de Quebra do Cromossomo/efeitos da radiação , Dano ao DNA , Análise Mutacional de DNA , Regulação Neoplásica da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Melanócitos/metabolismo , Melanócitos/patologia , Melanoma/patologia , Mutagênese/efeitos da radiação , Mutação/efeitos da radiação , Oncogenes/genética , Raios Ultravioleta/efeitos adversos
10.
Nature ; 486(7403): 405-9, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22722202

RESUMO

Breast carcinoma is the leading cause of cancer-related mortality in women worldwide, with an estimated 1.38 million new cases and 458,000 deaths in 2008 alone. This malignancy represents a heterogeneous group of tumours with characteristic molecular features, prognosis and responses to available therapy. Recurrent somatic alterations in breast cancer have been described, including mutations and copy number alterations, notably ERBB2 amplifications, the first successful therapy target defined by a genomic aberration. Previous DNA sequencing studies of breast cancer genomes have revealed additional candidate mutations and gene rearrangements. Here we report the whole-exome sequences of DNA from 103 human breast cancers of diverse subtypes from patients in Mexico and Vietnam compared to matched-normal DNA, together with whole-genome sequences of 22 breast cancer/normal pairs. Beyond confirming recurrent somatic mutations in PIK3CA, TP53, AKT1, GATA3 and MAP3K1, we discovered recurrent mutations in the CBFB transcription factor gene and deletions of its partner RUNX1. Furthermore, we have identified a recurrent MAGI3-AKT3 fusion enriched in triple-negative breast cancer lacking oestrogen and progesterone receptors and ERBB2 expression. The MAGI3-AKT3 fusion leads to constitutive activation of AKT kinase, which is abolished by treatment with an ATP-competitive AKT small-molecule inhibitor.


Assuntos
Neoplasias da Mama/classificação , Neoplasias da Mama/genética , Mutação/genética , Translocação Genética/genética , Algoritmos , Neoplasias da Mama/patologia , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade beta de Fator de Ligação ao Core/genética , Análise Mutacional de DNA , Exoma/genética , Feminino , Fusão Gênica/genética , Humanos , Proteínas de Membrana/genética , México , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Vietnã
11.
Nature ; 470(7333): 214-20, 2011 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21307934

RESUMO

Prostate cancer is the second most common cause of male cancer deaths in the United States. However, the full range of prostate cancer genomic alterations is incompletely characterized. Here we present the complete sequence of seven primary human prostate cancers and their paired normal counterparts. Several tumours contained complex chains of balanced (that is, 'copy-neutral') rearrangements that occurred within or adjacent to known cancer genes. Rearrangement breakpoints were enriched near open chromatin, androgen receptor and ERG DNA binding sites in the setting of the ETS gene fusion TMPRSS2-ERG, but inversely correlated with these regions in tumours lacking ETS fusions. This observation suggests a link between chromatin or transcriptional regulation and the genesis of genomic aberrations. Three tumours contained rearrangements that disrupted CADM2, and four harboured events disrupting either PTEN (unbalanced events), a prostate tumour suppressor, or MAGI2 (balanced events), a PTEN interacting protein not previously implicated in prostate tumorigenesis. Thus, genomic rearrangements may arise from transcriptional or chromatin aberrancies and engage prostate tumorigenic mechanisms.


Assuntos
Genoma Humano/genética , Neoplasias da Próstata/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/genética , Estudos de Casos e Controles , Moléculas de Adesão Celular/genética , Cromatina/genética , Cromatina/metabolismo , Aberrações Cromossômicas , Pontos de Quebra do Cromossomo , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica , Guanilato Quinases , Humanos , Masculino , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Recombinação Genética/genética , Transdução de Sinais/genética , Transcrição Gênica
12.
Nature ; 471(7339): 467-72, 2011 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-21430775

RESUMO

Multiple myeloma is an incurable malignancy of plasma cells, and its pathogenesis is poorly understood. Here we report the massively parallel sequencing of 38 tumour genomes and their comparison to matched normal DNAs. Several new and unexpected oncogenic mechanisms were suggested by the pattern of somatic mutation across the data set. These include the mutation of genes involved in protein translation (seen in nearly half of the patients), genes involved in histone methylation, and genes involved in blood coagulation. In addition, a broader than anticipated role of NF-κB signalling was indicated by mutations in 11 members of the NF-κB pathway. Of potential immediate clinical relevance, activating mutations of the kinase BRAF were observed in 4% of patients, suggesting the evaluation of BRAF inhibitors in multiple myeloma clinical trials. These results indicate that cancer genome sequencing of large collections of samples will yield new insights into cancer not anticipated by existing knowledge.


Assuntos
Genoma Humano/genética , Mieloma Múltiplo/genética , Mutação/genética , Sequência de Aminoácidos , Coagulação Sanguínea/genética , Ilhas de CpG/genética , Análise Mutacional de DNA , Reparo do DNA/genética , Éxons/genética , Complexo Multienzimático de Ribonucleases do Exossomo , Genômica , Histonas/metabolismo , Proteínas de Homeodomínio/genética , Homeostase/genética , Humanos , Metilação , Modelos Moleculares , Dados de Sequência Molecular , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/enzimologia , Mieloma Múltiplo/metabolismo , NF-kappa B/metabolismo , Oncogenes/genética , Fases de Leitura Aberta/genética , Biossíntese de Proteínas/genética , Conformação Proteica , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo , Processamento Pós-Transcricional do RNA/genética , Ribonucleases/química , Ribonucleases/genética , Transdução de Sinais/genética , Transcrição Gênica/genética
13.
Hum Mutat ; 36(4): E2423-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25703262

RESUMO

Oncotator is a tool for annotating genomic point mutations and short nucleotide insertions/deletions (indels) with variant- and gene-centric information relevant to cancer researchers. This information is drawn from 14 different publicly available resources that have been pooled and indexed, and we provide an extensible framework to add additional data sources. Annotations linked to variants range from basic information, such as gene names and functional classification (e.g. missense), to cancer-specific data from resources such as the Catalogue of Somatic Mutations in Cancer (COSMIC), the Cancer Gene Census, and The Cancer Genome Atlas (TCGA). For local use, Oncotator is freely available as a python module hosted on Github (https://github.com/broadinstitute/oncotator). Furthermore, Oncotator is also available as a web service and web application at http://www.broadinstitute.org/oncotator/.


Assuntos
Bases de Dados Genéticas , Neoplasias/genética , Biologia Computacional/métodos , Variação Genética , Genômica/métodos , Humanos , Internet , Neoplasias/diagnóstico , Neoplasias/metabolismo , Navegador
14.
Sensors (Basel) ; 15(1): 2104-36, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25608215

RESUMO

Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.


Assuntos
Redes de Comunicação de Computadores , Segurança Computacional , Tecnologia sem Fio , Algoritmos , Probabilidade
15.
J Proteome Res ; 13(11): 4676-85, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25227318

RESUMO

Deficient chloride transport through cystic fibrosis (CF) transmembrane conductance regulator (CFTR) causes lethal complications in CF patients. CF is the most common autosomal recessive genetic disease, which is caused by mutations in the CFTR gene; thus, CFTR mutants can serve as primary targets for drugs to modulate and rescue the ion channel's function. The first step of drug modulation is to increase the expression of CFTR in the apical plasma membrane (PM); thus, accurate measurement of CFTR in the PM is desired. This work reports a tandem enrichment strategy to prepare PM CFTR and uses a stable isotope labeled CFTR sample as the quantitation reference to measure the absolute amount of apical PM expression of CFTR in CFBE 41o- cells. It was found that CFBE 41o- cells expressing wild-type CFTR (wtCFTR), when cultured on plates, had 2.9 ng of the protein in the apical PM per million cells; this represented 10% of the total CFTR found in the cells. When these cells were polarized on filters, the apical PM expression of CFTR increased to 14%. Turnover of CFTR in the apical PM of baby hamster kidney cells overexpressing wtCFTR (BHK-wtCFTR) was also quantified by targeted proteomics based on multiple reaction monitoring mass spectrometry; wtCFTR had a half-life of 29.0 ± 2.5 h in the apical PM. This represents the first direct measurement of CFTR turnover using stable isotopes. The absolute quantitation and turnover measurements of CFTR in the apical PM can significantly facilitate understanding the disease mechanism of CF and thus the development of new disease-modifying drugs. Absolute CFTR quantitation allows for direct result comparisons among analyses, analysts, and laboratories and will greatly amplify the overall outcome of CF research and therapy.


Assuntos
Membrana Celular/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/tratamento farmacológico , Fibrose Cística/metabolismo , Modelos Moleculares , Proteômica/métodos , Animais , Biotinilação , Linhagem Celular , Cloretos/metabolismo , Cricetinae , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/química , Meia-Vida , Humanos , Transporte de Íons/fisiologia , Marcação por Isótopo , Espectrometria de Massas
16.
Nature ; 450(7171): 893-8, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-17982442

RESUMO

Somatic alterations in cellular DNA underlie almost all human cancers. The prospect of targeted therapies and the development of high-resolution, genome-wide approaches are now spurring systematic efforts to characterize cancer genomes. Here we report a large-scale project to characterize copy-number alterations in primary lung adenocarcinomas. By analysis of a large collection of tumours (n = 371) using dense single nucleotide polymorphism arrays, we identify a total of 57 significantly recurrent events. We find that 26 of 39 autosomal chromosome arms show consistent large-scale copy-number gain or loss, of which only a handful have been linked to a specific gene. We also identify 31 recurrent focal events, including 24 amplifications and 7 homozygous deletions. Only six of these focal events are currently associated with known mutations in lung carcinomas. The most common event, amplification of chromosome 14q13.3, is found in approximately 12% of samples. On the basis of genomic and functional analyses, we identify NKX2-1 (NK2 homeobox 1, also called TITF1), which lies in the minimal 14q13.3 amplification interval and encodes a lineage-specific transcription factor, as a novel candidate proto-oncogene involved in a significant fraction of lung adenocarcinomas. More generally, our results indicate that many of the genes that are involved in lung adenocarcinoma remain to be discovered.


Assuntos
Adenocarcinoma/genética , Genoma Humano/genética , Neoplasias Pulmonares/genética , Neoplasias/genética , Linhagem Celular Tumoral , Deleção Cromossômica , Cromossomos Humanos Par 14/genética , Amplificação de Genes/genética , Genômica , Genótipo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Perda de Heterozigosidade/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Proto-Oncogene Mas , Interferência de RNA , Fator Nuclear 1 de Tireoide , Fatores de Transcrição/genética
17.
J Immunother Cancer ; 11(4)2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37045474

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR)-T cell-based immunotherapy constitutes a revolutionary advance for treatment of relapsed/refractory hematological malignancies. Nevertheless, cytokine release and immune effector cell-associated neurotoxicity syndromes are life-threatening toxicities in which the endothelium could be a pathophysiological substrate. Furthermore, differential diagnosis from sepsis, highly incident in these patients, is challenging. Suitable laboratory tools could be determinant for their appropriate management. METHODS: Sixty-two patients treated with CAR-T cell immunotherapy for hematological malignancies (n=46 with CD19-positive diseases, n=16 with multiple myeloma) were included. Plasma samples were obtained: before CAR-T cell infusion (baseline); after 24-48 hours; at suspicion of any toxicity onset and 24-48 hours after immunomodulatory treatment. Biomarkers of endothelial dysfunction (soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble TNF receptor 1 (sTNFRI), thrombomodulin (TM), soluble suppression of tumorigenesis-2 factor (ST2), angiopoietin-2 (Ang-2)), innate immunity activation (neutrophil extracellular traps (NETs), soluble C5b-9 (sC5b-9)) and hemostasis/fibrinolysis (von Willebrand Factor antigen (VWF:Ag), ADAMTS-13 (A13), α2-antiplasmin (α2-AP), plasminogen activator inhibitor-1 antigen (PAI-1 Ag)) were measured and compared with those in cohorts of patients with sepsis and healthy donors. RESULTS: Patients who developed CAR-T cell toxicities presented increased levels of sVCAM-1, sTNFRI and ST2 at the clinical onset versus postinfusion values. Twenty-four hours after infusion, ST2 levels were good predictors of any CAR-T cell toxicity, and combination of ST2, Ang-2 and NETs differentiated patients requiring intensive care unit admission from those with milder clinical presentations. Association of Ang-2, NETs, sC5b-9, VWF:Ag and PAI-1 Ag showed excellent discrimination between severe CAR-T cell toxicities and sepsis. CONCLUSIONS: This study provides relevant contributions to the current knowledge of the CAR-T cell toxicities pathophysiology. Markers of endotheliopathy, innate immunity activation and hemostatic imbalance appear as potential laboratory tools for their prediction, severity and differential diagnosis.


Assuntos
Neoplasias Hematológicas , Hemostáticos , Sepse , Humanos , Linfócitos T , Fator de von Willebrand , Diagnóstico Diferencial , Inibidor 1 de Ativador de Plasminogênio , Proteína 1 Semelhante a Receptor de Interleucina-1 , Hemostasia , Neoplasias Hematológicas/terapia
18.
Sci Rep ; 13(1): 5665, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-37024714

RESUMO

Purkinje cell (PC) loss occurs at an early age in patients and animal models of Niemann-Pick Type C (NPC), a lysosomal storage disease caused by mutations in the Npc1 or Npc2 genes. Although degeneration of PCs occurs early in NPC, little is known about how NPC1 deficiency affects the postnatal development of PCs. Using the Npc1nmf164 mouse model, we found that NPC1 deficiency significantly affected the postnatal development of PC dendrites and synapses. The developing dendrites of Npc1nmf164 PCs were significantly deficient in mitochondria and lysosomes. Furthermore, anabolic (mTORC1) and catabolic (TFEB) signaling pathways were not only perturbed but simultaneously activated in NPC1-deficient PCs, suggesting a loss of metabolic balance. We also found that mice with conditional heterozygous deletion of the Phosphatase and Tensin Homolog Deleted on Chromosome 10 gene (Pten-cHet), an inhibitor of mTORC1, showed similar early dendritic alterations in PCs to those found in Npc1-deficient mice. However, in contrast to Npc1nmf164 mice, Pten-cHet mice exhibited the overactivation of the mTORC1 pathway but with a strong inhibition of TFEB signaling, along with no dendritic mitochondrial reductions by the end of their postnatal development. Our data suggest that disruption of the lysosomal-metabolic signaling in PCs causes dendritic and synaptic developmental deficits that precede and promote their early degeneration in NPC.


Assuntos
Doença de Niemann-Pick Tipo C , Células de Purkinje , Camundongos , Animais , Células de Purkinje/metabolismo , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Animais de Doenças , Lisossomos/metabolismo
19.
Expert Rev Respir Med ; 16(11-12): 1237-1245, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36351310

RESUMO

OBJECTIVE: We compared dexmedetomidine-remifentanil vs. propofol-remifentanil in terms of safety and quality during sedation for Endobronchial ultrasonography (EBUS). METHODS: A randomized, double-blind trial. Outpatients undergoing EBUS randomly received 1 µg/kg/hour dexmedetomidine or a target concentration of 2.5 µg/mL propofol, both combined with remifentanil initially targeted at 1.5 ng/mL and subsequently titrated. Additional sedatives were restricted. The primary outcome was the need for airway rescue interventions to treat oxygen desaturation. RESULTS: Twenty-eight patients received dexmedetomidine-remifentanil and 27 received propofol-remifentanil. Airway rescue interventions were fewer in the dexmedetomidine group vs. the propofol one (23 vs. 76% patients, relative risk 3.21 (95% CI 1.55-6.64, P < 0.002)). Desaturation in the dexmedetomidine group was always resolved by increasing nasal oxygen flow, whereas additional interventions were needed in 60% of patients receiving propofol. Hypotension was more frequent in the propofol group, while hypertension, bradycardia and coughing were similar in both. Bronchoscopists' and patients' satisfaction were similar, although in the dexmedetomidine group two patients needed additional sedatives and two patients would not repeat the sedation technique. CONCLUSION: Moderate sedation with dexmedetomidine-remifentanil for EBUS is safer than deep sedation with propofol-remifentanil but it would occasionally need additional sedatives to ensure patient satisfaction.


Assuntos
Sedação Profunda , Dexmedetomidina , Propofol , Humanos , Propofol/efeitos adversos , Remifentanil/efeitos adversos , Dexmedetomidina/efeitos adversos , Sedação Consciente/métodos , Hipnóticos e Sedativos , Oxigênio , Método Duplo-Cego
20.
Bone Marrow Transplant ; 57(5): 721-728, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35184147

RESUMO

Engraftment syndrome (ES) is a common complication after autologous hematopoietic cell transplantation (auto-HCT) whose pathophysiological substrate remains unclear. We investigated whether endothelial damage could contribute to ES. Circulating ECs-damage biomarkers were measured in plasma from patients with (ES; n = 14) or without ES (non-ES; n = 20), collected at different time points: before HCT, 5 (S5) and 10 days (S10) after HCT, and at either the ES onset (SON) or the discharge day (SDIS). Also, cultured endothelial cells (ECs) were exposed to serum samples, obtained at the same points, to evaluate changes in ECs-activation (ICAM-1, VE-Cadherin) biomarkers, the reactivity of ECs towards leukocytes, and activation of intracellular signaling proteins related to inflammation (p38MAPK) and proliferation (Erk1/2). Results showed that circulating VWF, sTNFR1 and sVCAM-1 levels were higher in ES patients at all the points assessed, especially at SON. In vitro results showed an increased ICAM-1 expression on ECs exposed to ES samples vs. non-ES samples, especially to S5, with elevated leukocyte adhesion. Also, a lower VE-Cadherin expression and an increased phosphorylation of p38MAPK and Erk1/2 proteins were observed in ECs exposed to ES vs. non-ES samples. Our results indicate that endothelial activation precedes ES development and could be one of its pathophysiological substrates.


Assuntos
Doenças Hematológicas , Transplante de Células-Tronco Hematopoéticas , Doenças do Sistema Imunitário , Biomarcadores/metabolismo , Células Endoteliais/metabolismo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Molécula 1 de Adesão Intercelular , Fenótipo
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