Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
Cell Commun Signal ; 21(1): 295, 2023 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864183

RESUMO

BACKGROUND: When ectopically overexpressed, anticancer genes, such as TRAIL, PAR4 and ORCTL3, specifically destroy tumour cells without harming untransformed cells. Anticancer genes can not only serve as powerful tumour specific therapy tools but studying their mode of action can reveal mechanisms underlying the neoplastic transformation, sustenance and spread. METHODS: Anticancer gene discovery is normally accidental. Here we describe a systematic, gain of function, forward genetic screen in mammalian cells to isolate novel anticancer genes of human origin. Continuing with over 30,000 transcripts from our previous study, 377 cell death inducing genes were subjected to screening. FBLN5 was chosen, as a proof of principle, for mechanistic gene expression profiling, comparison pathways analyses and functional studies. RESULTS: Sixteen novel anticancer genes were isolated; these included non-coding RNAs, protein-coding genes and novel transcripts, such as ZNF436-AS1, SMLR1, TMEFF2, LINC01529, HYAL2, NEIL2, FBLN5, YPEL4 and PHKA2-processed transcript. FBLN5 selectively caused inhibition of MYC in COS-7 (transformed) cells but not in CV-1 (normal) cells. MYC was identified as synthetic lethality partner of FBLN5 where MYC transformed CV-1 cells experienced cell death upon FBLN5 transfection, whereas FBLN5 lost cell death induction in MCF-7 cells upon MYC knockdown. CONCLUSIONS: Sixteen novel anticancer genes are present in human genome including FBLN5. MYC is a synthetic lethality partner of FBLN5. Video Abstract.


Assuntos
Transformação Celular Neoplásica , Perfilação da Expressão Gênica , Animais , Humanos , Proteínas da Matriz Extracelular/metabolismo , Testes Genéticos , Mamíferos/metabolismo , Células MCF-7 , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Fosforilase Quinase , Fatores de Transcrição/genética
2.
Lancet Planet Health ; 7(7): e590-e599, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37438000

RESUMO

BACKGROUND: To improve physical activity in Latin American cities, several interventions have been promoted, such as Open Streets programmes. Our study aims to quantify the health and economic effects of Open Streets-related physical activity in 15 Latin American cities. METHODS: We used a quantitative health impact assessment approach to estimate annual premature deaths and disease incidence (ischaemic heart disease, ischaemic stroke, type 2 diabetes, colon cancer, breast cancer, and dementia) avoided, the disability-adjusted life-years (DALYs) gained, and the cost saving (from reduced premature mortality) related to increased physical activity from Open Streets programmes in 15 Latin American cities. Input data were obtained from scientific publications, reports, and open street city surveys spanning 2017 to 2019. Physical activity data were converted to metabolic equivalent of the task. Exposure-response relationship functions were applied to estimate relative risk and population-attributable fraction, enabling the assessment of premature deaths and disease incidence. FINDINGS: The percentage of male users of the Open Streets programmes ranged from 55% (27 500 of 50 000 in Guatemala) to 75% (2250 of 3000 in El Alto, Bolivia), and female users ranged from 25% (750; El Alto) to 45% (22 500; Guatemala). We estimated that the current Open Streets programmes in the 15 Latin American cities studied could prevent 363 (95% CI 271-494) annual premature deaths due to increased physical activity, with an annual economic impact of US$194·1 million (144·9 million-263·9 million) saved and an annual reduction of 1036·7 DALYs (346·7-1778·3). If one Open Streets event is added per week in each of those cities, the potential benefit could increase to 496 (370 to 677) premature deaths prevented each year. INTERPRETATION: Open Streets programmes in Latin America can provide health and economic benefits related to increased physical activity and can be used as a health promotion and disease prevention tool. FUNDING: EU's Horizon 2020 research and innovation programme.


Assuntos
Isquemia Encefálica , Diabetes Mellitus Tipo 2 , Acidente Vascular Cerebral , Feminino , Masculino , Humanos , América Latina/epidemiologia , Avaliação do Impacto na Saúde
3.
PLoS Pathog ; 19(7): e1011494, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37523412

RESUMO

Infections by Human T cell Leukaemia Virus type 1 (HTLV-1) persist for the lifetime of the host by integrating into the genome of CD4+ T cells. Proviral gene expression is essential for proviral survival and the maintenance of the proviral load, through the pro-proliferative changes it induces in infected cells. Despite their role in HTLV-1 infection and a persistent cytotoxic T lymphocyte response raised against the virus, proviral transcripts from the sense-strand are rarely detected in fresh cells extracted from the peripheral blood, and have recently been found to be expressed intermittently by a small subset of cells at a given time. Ex vivo culture of infected cells prompts synchronised proviral expression in infected cells from peripheral blood, allowing the study of factors involved in reactivation in primary cells. Here, we used bulk RNA-seq to examine the host transcriptome over six days in vitro, following proviral reactivation in primary peripheral CD4+ T cells isolated from subjects with non-malignant HTLV-1 infection. Infected cells displayed a conserved response to reactivation, characterised by discrete stages of gene expression, cell division and subsequently horizontal transmission of the virus. We observed widespread changes in Polycomb gene expression following reactivation, including an increase in PRC2 transcript levels and diverse changes in the expression of PRC1 components. We hypothesize that these transcriptional changes constitute a negative feedback loop that maintains proviral latency by re-deposition of H2AK119ub1 following the end of proviral expression. Using RNAi, we found that certain deubiquitinases, BAP1, USP14 and OTUD5 each promote proviral transcription. These data demonstrate the detailed trajectory of HTLV-1 proviral reactivation in primary HTLV-1-carrier lymphocytes and the impact on the host cell.


Assuntos
Infecções por HTLV-I , Vírus Linfotrópico T Tipo 1 Humano , Humanos , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Provírus/genética , Transcriptoma , Linfócitos T CD4-Positivos , Carga Viral , Ubiquitina Tiolesterase/metabolismo
4.
Mol Cell ; 83(16): 2925-2940.e8, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37499663

RESUMO

Homologous recombination (HR) is essential for error-free repair of DNA double-strand breaks, perturbed replication forks (RFs), and post-replicative single-stranded DNA (ssDNA) gaps. To initiate HR, the recombination mediator and tumor suppressor protein BRCA2 facilitates nucleation of RAD51 on ssDNA prior to stimulation of RAD51 filament growth by RAD51 paralogs. Although ssDNA binding by BRCA2 has been implicated in RAD51 nucleation, the function of double-stranded DNA (dsDNA) binding by BRCA2 remains unclear. Here, we exploit single-molecule (SM) imaging to visualize BRCA2-mediated RAD51 nucleation in real time using purified proteins. We report that BRCA2 nucleates and stabilizes RAD51 on ssDNA either directly or through an unappreciated diffusion-assisted delivery mechanism involving binding to and sliding along dsDNA, which requires the cooperative action of multiple dsDNA-binding modules in BRCA2. Collectively, our work reveals two distinct mechanisms of BRCA2-dependent RAD51 loading onto ssDNA, which we propose are critical for its diverse functions in maintaining genome stability and cancer suppression.


Assuntos
Proteína BRCA2 , Rad51 Recombinase , Humanos , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Proteínas de Ligação a DNA/metabolismo , DNA de Cadeia Simples/genética , DNA/metabolismo , Reparo do DNA , Ligação Proteica
5.
Mol Cell ; 82(24): 4664-4680.e9, 2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36455556

RESUMO

POLQ is a key effector of DSB repair by microhomology-mediated end-joining (MMEJ) and is overexpressed in many cancers. POLQ inhibitors confer synthetic lethality in HR and Shieldin-deficient cancer cells, which has been proposed to reflect a critical dependence on the DSB repair pathway by MMEJ. Whether POLQ also operates independent of MMEJ remains unexplored. Here, we show that POLQ-deficient cells accumulate post-replicative ssDNA gaps upon BRCA1/2 loss or PARP inhibitor treatment. Biochemically, cooperation between POLQ helicase and polymerase activities promotes RPA displacement and ssDNA-gap fill-in, respectively. POLQ is also capable of microhomology-mediated gap skipping (MMGS), which generates deletions during gap repair that resemble the genomic scars prevalent in POLQ overexpressing cancers. Our findings implicate POLQ in mutagenic post-replicative gap sealing, which could drive genome evolution in cancer and whose loss places a critical dependency on HR for gap protection and repair and cellular viability.


Assuntos
Quebras de DNA de Cadeia Dupla , Neoplasias , Humanos , Replicação do DNA/genética , Instabilidade Genômica , DNA de Cadeia Simples/genética , Mutações Sintéticas Letais , Reparo do DNA por Junção de Extremidades , Neoplasias/genética
6.
Artigo em Inglês | MEDLINE | ID: mdl-36078753

RESUMO

In Peru, major disasters like the 2007 Pisco earthquake have produced high rates of post-traumatic stress. However, evidence is still needed to strengthen interventions. In 2021, a major earthquake struck Piura, in northern Peru. In this context, we aimed to assess the prevalence of PTSD and its associated factors. A cross-sectional study was conducted during August-September 2021 in people who experienced the 6.1 Piura earthquake on 30 July 2021. The questionnaire included the PCL-C, CD-RISC, ISI, HFIAS, and additional demographic data. Generalized linear models were used. The prevalence of PTSD was 20.3%. Household income was between PEN 2001 and 3000 (PR = 4.26, 95% CI: 1.08-16.75), smoking (PR = 2.49, 95% CI: 1.03-6.01), experience of a nervous breakdown (PR = 1.83, 95% CI: 1.09-3.09), moderate food insecurity (PR = 2.91, 95% CI: 1.10-7.73), and severe insomnia (PR = 8.25, 95% CI: 2.22-30.71) increased the prevalence of PTSD. One out of five individuals experienced post-traumatic stress symptoms after the 2021 earthquake in Piura, which varies depending on socioeconomic, psychosocial, and individual factors. Further research should strengthen these findings to ensure a fair and early mental health intervention against new seismic events in this and other Peruvian regions.


Assuntos
Terremotos , Transtornos de Estresse Pós-Traumáticos , Estudos Transversais , Humanos , Peru/epidemiologia , Prevalência , Fatores de Risco , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários , Sobreviventes/psicologia
7.
Nature ; 601(7892): 268-273, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34937945

RESUMO

DNA double-stranded breaks (DSBs) are deleterious lesions, and their incorrect repair can drive cancer development1. HELQ is a superfamily 2 helicase with 3' to 5' polarity, and its disruption in mice confers germ cells loss, infertility and increased predisposition to ovarian and pituitary tumours2-4. At the cellular level, defects in HELQ result in hypersensitivity to cisplatin and mitomycin C, and persistence of RAD51 foci after DNA damage3,5. Notably, HELQ binds to RPA and the RAD51-paralogue BCDX2 complex, but the relevance of these interactions and how HELQ functions in DSB repair remains unclear3,5,6. Here we show that HELQ helicase activity and a previously unappreciated DNA strand annealing function are differentially regulated by RPA and RAD51. Using biochemistry analyses and single-molecule imaging, we establish that RAD51 forms a complex with and strongly stimulates HELQ as it translocates during DNA unwinding. By contrast, RPA inhibits DNA unwinding by HELQ but strongly stimulates DNA strand annealing. Mechanistically, we show that HELQ possesses an intrinsic ability to capture RPA-bound DNA strands and then displace RPA to facilitate annealing of complementary sequences. Finally, we show that HELQ deficiency in cells compromises single-strand annealing and microhomology-mediated end-joining pathways and leads to bias towards long-tract gene conversion tracts during homologous recombination. Thus, our results implicate HELQ in multiple arms of DSB repair through co-factor-dependent modulation of intrinsic translocase and DNA strand annealing activities.


Assuntos
Quebras de DNA de Cadeia Dupla , DNA Helicases , Reparo do DNA , Rad51 Recombinase , Proteína de Replicação A , DNA , DNA Helicases/metabolismo , DNA de Cadeia Simples , Rad51 Recombinase/metabolismo , Proteína de Replicação A/metabolismo
8.
Mol Cell ; 81(5): 1058-1073.e7, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421363

RESUMO

Homologous recombination (HR) is an essential DNA double-strand break (DSB) repair mechanism, which is frequently inactivated in cancer. During HR, RAD51 forms nucleoprotein filaments on RPA-coated, resected DNA and catalyzes strand invasion into homologous duplex DNA. How RAD51 displaces RPA and assembles into long HR-proficient filaments remains uncertain. Here, we employed single-molecule imaging to investigate the mechanism of nematode RAD-51 filament growth in the presence of BRC-2 (BRCA2) and RAD-51 paralogs, RFS-1/RIP-1. BRC-2 nucleates RAD-51 on RPA-coated DNA, whereas RFS-1/RIP-1 acts as a "chaperone" to promote 3' to 5' filament growth via highly dynamic engagement with 5' filament ends. Inhibiting ATPase or mutation in the RFS-1 Walker box leads to RFS-1/RIP-1 retention on RAD-51 filaments and hinders growth. The rfs-1 Walker box mutants display sensitivity to DNA damage and accumulate RAD-51 complexes non-functional for HR in vivo. Our work reveals the mechanism of RAD-51 nucleation and filament growth in the presence of recombination mediators.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Proteínas de Transporte/genética , DNA de Helmintos/genética , Proteínas de Ligação a DNA/genética , Rad51 Recombinase/genética , Reparo de DNA por Recombinação , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Transporte/metabolismo , Quebras de DNA de Cadeia Dupla , DNA de Helmintos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutação , Ligação Proteica , Rad51 Recombinase/metabolismo , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Transdução de Sinais , Imagem Individual de Molécula
9.
Artigo em Inglês | MEDLINE | ID: mdl-33467516

RESUMO

Background: Environmental health is a growing area of knowledge, continually increasing and updating the body of evidence linking the environment to human health. Aim: This study summarizes the epidemiological evidence on environmental risk factors from meta-analyses through an umbrella review. Methods: An umbrella review was conducted on meta-analyses of cohort, case-control, case-crossover, and time-series studies that evaluated the associations between environmental risk factors and health outcomes defined as incidence, prevalence, and mortality. The specific search strategy was designed in PubMed using free text and Medical Subject Headings (MeSH) terms related to risk factors, environment, health outcomes, observational studies, and meta-analysis. The search was limited to English, Spanish, and French published articles and studies on humans. The search was conducted on September 20, 2020. Risk factors were defined as any attribute, characteristic, or exposure of an individual that increases the likelihood of developing a disease or death. The environment was defined as the external elements and conditions that surround, influence, and affect a human organism or population's life and development. The environment definition included the physical environment such as nature, built environment, or pollution, but not the social environment. We excluded occupational exposures, microorganisms, water, sanitation and hygiene (WASH), behavioral risk factors, and no-natural disasters. Results: This umbrella review found 197 associations among 69 environmental exposures and 83 diseases and death causes reported in 103 publications. The environmental factors found in this review were air pollution, environmental tobacco smoke, heavy metals, chemicals, ambient temperature, noise, radiation, and urban residential surroundings. Among these, we identified 65 environmental exposures defined as risk factors and 4 environmental protective factors. In terms of study design, 57 included cohort and/or case-control studies, and 46 included time-series and/or case-crossover studies. In terms of the study population, 21 included children, and the rest included adult population and both sexes. In this review, the largest body of evidence was found in air pollution (91 associations among 14 air pollution definitions and 34 diseases and mortality diagnoses), followed by environmental tobacco smoke with 24 associations. Chemicals (including pesticides) were the third larger group of environmental exposures found among the meta-analyses included, with 19 associations. Conclusion: Environmental exposures are an important health determinant. This review provides an overview of an evolving research area and should be used as a complementary tool to understand the connections between the environment and human health. The evidence presented by this review should help to design public health interventions and the implementation of health in all policies approach aiming to improve populational health.


Assuntos
Poluição do Ar , Adulto , Poluição do Ar/efeitos adversos , Criança , Exposição Ambiental/efeitos adversos , Saúde Ambiental , Poluição Ambiental , Feminino , Humanos , Masculino , Fatores de Risco
10.
Artigo em Inglês | MEDLINE | ID: mdl-35010548

RESUMO

(1) Background: Health disparities across the United States (U.S.) are increasing. Large variations in risk factors and health outcomes have been described among states from the U.S. (2) AIM. This study aims to describe health trends in morbidity, mortality, and risk factors from 1990 to 2019 in the State of Colorado. (3) Methods: We describe the measures of health loss for 286 causes of death, 369 diseases and injuries, and 87 risk factors for the state of Colorado from the Global Burden of Disease project estimates between 1990 to 2019. (4) Results: We found that 21,171 and 40,724 deaths were estimated in 1990 and 2019, respectively, in Colorado. The leading cause of death, in both sexes, in 1990 and 2019 was ischemic heart disease (IHD). The top leading disability-adjusted life years (DALY) diagnoses were IHD, followed by low back pain, chronic obstructive pulmonary disease, and opioid use disorder. In 2019, the top risk factors by DALYs in Colorado were smoking, drug use, high body mass index (BMI), alcohol use, high fasting plasma glucose, and high systolic blood pressure. (5) Conclusion: Non-communicable diseases and their related risk factors are the top leading causes of DALYs in Colorado. Findings support the need for policies to prevent non-communicable diseases, with special attention to musculoskeletal disorders and interventions to reduce tobacco, alcohol, and drug use.


Assuntos
Pessoas com Deficiência , Carga Global da Doença , Colorado/epidemiologia , Anos de Vida Ajustados por Deficiência , Feminino , Saúde Global , Humanos , Expectativa de Vida , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Risco
11.
Environ Health Perspect ; 128(1): 17001, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31939704

RESUMO

BACKGROUND: Trihalomethanes (THMs) are widespread disinfection by-products (DBPs) in drinking water, and long-term exposure has been consistently associated with increased bladder cancer risk. OBJECTIVE: We assessed THM levels in drinking water in the European Union as a marker of DBP exposure and estimated the attributable burden of bladder cancer. METHODS: We collected recent annual mean THM levels in municipal drinking water in 28 European countries (EU28) from routine monitoring records. We estimated a linear exposure-response function for average residential THM levels and bladder cancer by pooling data from studies included in the largest international pooled analysis published to date in order to estimate odds ratios (ORs) for bladder cancer associated with the mean THM level in each country (relative to no exposure), population-attributable fraction (PAF), and number of attributable bladder cancer cases in different scenarios using incidence rates and population from the Global Burden of Disease study of 2016. RESULTS: We obtained 2005-2018 THM data from EU26, covering 75% of the population. Data coverage and accuracy were heterogeneous among countries. The estimated population-weighted mean THM level was 11.7µg/L [standard deviation (SD) of 11.2]. The estimated bladder cancer PAF was 4.9% [95% confidence interval (CI): 2.5, 7.1] overall (range: 0-23%), accounting for 6,561 (95% CI: 3,389, 9,537) bladder cancer cases per year. Denmark and the Netherlands had the lowest PAF (0.0% each), while Cyprus (23.2%), Malta (17.9%), and Ireland (17.2%) had the highest among EU26. In the scenario where no country would exceed the current EU mean, 2,868 (95% CI: 1,522, 4,060; 43%) annual attributable bladder cancer cases could potentially be avoided. DISCUSSION: Efforts have been made to reduce THM levels in the European Union. However, assuming a causal association, current levels in certain countries still could lead to a considerable burden of bladder cancer that could potentially be avoided by optimizing water treatment, disinfection, and distribution practices, among other possible measures. https://doi.org/10.1289/EHP4495.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Trialometanos , Neoplasias da Bexiga Urinária/epidemiologia , Poluentes Químicos da Água , Água Potável/química , Europa (Continente)/epidemiologia , União Europeia , Humanos , Purificação da Água
12.
Sci Adv ; 5(11): eaay6804, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31807710

RESUMO

Sister chromatid cohesion requires cohesin to act as a protein linker to hold chromatids together. How cohesin tethers chromatids remains poorly understood. We have used optical tweezers to visualize cohesin as it holds DNA molecules. We show that cohesin complexes tether DNAs in the presence of Scc2/Scc4 and ATP demonstrating a conserved activity from yeast to humans. Cohesin forms two classes of tethers: a "permanent bridge" resisting forces over 80 pN and a force-sensitive "reversible bridge." The establishment of bridges requires physical proximity of dsDNA segments and occurs in a single step. "Permanent" cohesin bridges slide when they occur in trans, but cannot be removed when in cis. Therefore, DNAs occupy separate physical compartments in cohesin molecules. We finally demonstrate that cohesin tetramers can compact linear DNA molecules stretched by very low force (below 1 pN), consistent with the possibility that, like condensin, cohesin is also capable of loop extrusion.


Assuntos
Trifosfato de Adenosina/química , Proteínas de Ciclo Celular/química , Proteínas Cromossômicas não Histona/química , DNA Fúngico/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/química , Trifosfato de Adenosina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cromátides/química , Cromátides/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , DNA Fúngico/metabolismo , Humanos , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Coesinas
13.
PLoS Pathog ; 15(11): e1008164, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738810

RESUMO

The human T cell leukemia virus HTLV-1 establishes a persistent infection in vivo in which the viral sense-strand transcription is usually silent at a given time in each cell. However, cellular stress responses trigger the reactivation of HTLV-1, enabling the virus to transmit to a new host cell. Using single-molecule RNA FISH, we measured the kinetics of the HTLV-1 transcriptional reactivation in peripheral blood mononuclear cells (PBMCs) isolated from HTLV-1+ individuals. The abundance of the HTLV-1 sense and antisense transcripts was quantified hourly during incubation of the HTLV-1-infected PBMCs ex vivo. We found that, in each cell, the sense-strand transcription occurs in two distinct phases: the initial low-rate transcription is followed by a phase of rapid transcription. The onset of transcription peaked between 1 and 3 hours after the start of in vitro incubation. The variance in the transcription intensity was similar in polyclonal HTLV-1+ PBMCs (with tens of thousands of distinct provirus insertion sites), and in samples with a single dominant HTLV-1+ clone. A stochastic simulation model was developed to estimate the parameters of HTLV-1 proviral transcription kinetics. In PBMCs from a leukemic subject with one dominant T-cell clone, the model indicated that the average duration of HTLV-1 sense-strand activation by Tax (i.e. the rapid transcription) was less than one hour. HTLV-1 antisense transcription was stable during reactivation of the sense-strand. The antisense transcript HBZ was produced at an average rate of ~0.1 molecules per hour per HTLV-1+ cell; however, between 20% and 70% of HTLV-1-infected cells were HBZ-negative at a given time, the percentage depending on the individual subject. HTLV-1-infected cells are exposed to a range of stresses when they are drawn from the host, which initiate the viral reactivation. We conclude that whereas antisense-strand transcription is stable throughout the stress response, the HTLV-1 sense-strand reactivation is highly heterogeneous and occurs in short, self-terminating bursts.


Assuntos
Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Leucócitos Mononucleares/virologia , Análise de Célula Única/métodos , Proteínas Virais/genética , Ativação Viral/genética , Latência Viral/genética , Células Cultivadas , Regulação Viral da Expressão Gênica , Infecções por HTLV-I/genética , Humanos , Hibridização in Situ Fluorescente , Cinética , Processos Estocásticos , Replicação Viral
14.
Nat Immunol ; 20(10): 1372-1380, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31451789

RESUMO

In multicellular organisms, duplicated genes can diverge through tissue-specific gene expression patterns, as exemplified by highly regulated expression of RUNX transcription factor paralogs with apparent functional redundancy. Here we asked what cell-type-specific biologies might be supported by the selective expression of RUNX paralogs during Langerhans cell and inducible regulatory T cell differentiation. We uncovered functional nonequivalence between RUNX paralogs. Selective expression of native paralogs allowed integration of transcription factor activity with extrinsic signals, while non-native paralogs enforced differentiation even in the absence of exogenous inducers. DNA binding affinity was controlled by divergent amino acids within the otherwise highly conserved RUNT domain and evolutionary reconstruction suggested convergence of RUNT domain residues toward submaximal strength. Hence, the selective expression of gene duplicates in specialized cell types can synergize with the acquisition of functional differences to enable appropriate gene expression, lineage choice and differentiation in the mammalian immune system.


Assuntos
Subunidades alfa de Fatores de Ligação ao Core/genética , Sistema Imunitário/fisiologia , Células de Langerhans/fisiologia , Especificidade de Órgãos/genética , Linfócitos T Reguladores/fisiologia , Animais , Diferenciação Celular , Linhagem da Célula , Sequência Conservada , Evolução Molecular , Duplicação Gênica , Humanos , Mamíferos , Transdução de Sinais , Transcriptoma
15.
Artigo em Inglês | MEDLINE | ID: mdl-30917598

RESUMO

Background: Environmental factors determine children's health. Quantifying the health impacts related to environmental hazards for children is essential to prioritize interventions to improve health in Europe. Objective: This study aimed to assess the burden of childhood disease due to environmental risks across the European Union. Methods: We conducted an environmental burden of childhood disease assessment in the 28 countries of the EU (EU28) for seven environmental risk factors (particulate matter less than 10 micrometer of diameter (PM10) and less than 2.5 micrometer of diameter (PM2.5), ozone, secondhand smoke, dampness, lead, and formaldehyde). The primary outcome was disability-adjusted life years (DALYs), assessed from exposure data provided by the World Health Organization, Global Burden of Disease project, scientific literature, and epidemiological risk estimates. Results: The seven studied environmental risk factors for children in the EU28 were responsible for around 211,000 DALYs annually. Particulate matter (PM10 and PM2.5) was the main environmental risk factor, producing 59% of total DALYs (125,000 DALYs), followed by secondhand smoke with 20% of all DALYs (42,500 DALYs), ozone 11% (24,000 DALYs), dampness 6% (13,000 DALYs), lead 3% (6200 DALYs), and formaldehyde 0.2% (423 DALYs). Conclusions: Environmental exposures included in this study were estimated to produce 211,000 DALYs each year in children in the EU28, representing 2.6% of all DALYs in children. Among the included environmental risk factors, air pollution (particulate matter and ozone) was estimated to produce the highest burden of disease in children in Europe, half of which was due to the effects of PM10 on infant mortality. Effective policies to reduce environmental pollutants across Europe are needed.


Assuntos
Saúde da Criança , Exposição Ambiental/efeitos adversos , Adolescente , Poluição do Ar/efeitos adversos , Criança , Pré-Escolar , Doença , Europa (Continente) , Formaldeído/efeitos adversos , Humanos , Umidade , Lactente , Mortalidade Infantil , Recém-Nascido , Chumbo/efeitos adversos , Ozônio/efeitos adversos , Material Particulado/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos
16.
Artigo em Inglês | MEDLINE | ID: mdl-30764538

RESUMO

The promotion of physical activity through better urban design is one pathway by which health and well-being improvements can be achieved. This study aimed to quantify health and health-related economic impacts associated with physical activity in an urban riverside park regeneration project in Barcelona, Spain. We used data from Barcelona local authorities and meta-analysis assessing physical activity and health outcomes to develop and apply the "Blue Active Tool". We estimated park user health impacts in terms of all-cause mortality, morbidity (ischemic heart disease; ischemic stroke; type 2 diabetes; cancers of the colon and breast; and dementia), disability-adjusted life years (DALYs) and health-related economic impacts. We estimated that 5753 adult users visited the riverside park daily and performed different types of physical activity (walking for leisure or to/from work, cycling, and running). Related to the physical activity conducted on the riverside park, we estimated an annual reduction of 7.3 deaths (95% CI: 5.4; 10.2), and 6.2 cases of diseases (95% CI: 2.0; 11.6). This corresponds to 11.9 DALYs (95% CI: 3.4; 20.5) and an annual health-economic impact of 23.4 million euros (95% CI: 17.2 million; 32.8 million). The urban regeneration intervention of this riverside park provides health and health-related economic benefits to the population using the infrastructure.


Assuntos
Planejamento Ambiental , Exercício Físico , Promoção da Saúde/métodos , Parques Recreativos , Saúde Pública , Reforma Urbana/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Custo-Benefício , Planejamento Ambiental/economia , Feminino , Promoção da Saúde/economia , Humanos , Masculino , Pessoa de Meia-Idade , Parques Recreativos/economia , Saúde Pública/economia , Saúde Pública/métodos , Anos de Vida Ajustados por Qualidade de Vida , Espanha , Reforma Urbana/economia , Adulto Jovem
17.
Science ; 362(6411)2018 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-30309918

RESUMO

The yeast SWR1 complex exchanges histone H2A in nucleosomes with Htz1 (H2A.Z in humans). The cryo-electron microscopy structure of the SWR1 complex bound to a nucleosome at 3.6-angstrom resolution reveals details of the intricate interactions between components of the SWR1 complex and its nucleosome substrate. Interactions between the Swr1 motor domains and the DNA wrap at superhelical location 2 distort the DNA, causing a bulge with concomitant translocation of the DNA by one base pair, coupled to conformational changes of the histone core. Furthermore, partial unwrapping of the DNA from the histone core takes place upon binding of nucleosomes to SWR1 complex. The unwrapping, as monitored by single-molecule data, is stabilized and has its dynamics altered by adenosine triphosphate binding but does not require hydrolysis.


Assuntos
Adenosina Trifosfatases/química , Nucleossomos/química , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatases/ultraestrutura , Trifosfato de Adenosina/metabolismo , Montagem e Desmontagem da Cromatina , Microscopia Crioeletrônica , Nucleossomos/ultraestrutura , Domínios Proteicos , Proteínas de Saccharomyces cerevisiae/ultraestrutura
18.
Med Clin (Barc) ; 151(5): 171-190, 2018 09 14.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30037695

RESUMO

BACKGROUND AND OBJECTIVES: The global burden of disease (GBD) project measures the health of populations worldwide on an annual basis, and results are available by country. We used the estimates of the GBD to summarise the state of health in Spain in 2016 and report trends in mortality and morbidity from 1990 to 2016. MATERIAL AND METHODS: GBD 2016 estimated disease burden due to 333 diseases and injuries, and 84 risk factors. The GBD list of causes is hierarchical and includes 3 top level categories, namely: 1) communicable, maternal, neonatal, and nutritional diseases; 2) non-communicable diseases (NCDs), and 3) injuries. Mortality and disability-adjusted life-years (DALYs), risk factors, and progress towards the sustainable development goals (SDGs) are presented based on the GBD 2016 data in Spain. RESULTS: There were 418,516 deaths in Spain in 2016, from a total population of 46.5 million, and 80.5% of them occurred in those aged 70 years and older. Overall, NCDs were the main cause of death: 388,617 (95% uncertainty interval 374,959-402,486), corresponding to 92.8% of all deaths. They were followed by 3.6% due to injuries with 15,052 (13,902-17,107) deaths, and 3.5% communicable diseases with 14,847 (13,208-16,482) deaths. The 5 leading specific causes of death were ischaemic heart disease (IHD, 14.6% of all deaths), Alzheimer disease and other dementias (13.6%), stroke (7.1%), chronic obstructive pulmonary disease (6.9%), and lung cancer (5.0%). Remarkable increases in mortality from 1990 to 2016 were observed in other cancers, lower respiratory infections, chronic kidney disease, and other cardiovascular disease, among others. On the contrary, road injuries moved down from 8th to 32nd position, and diabetes from 6th to 10th. Low back and neck pain became the number one cause of DALYs in Spain in 2016, just surpassing IHD, while Alzheimer disease moved from 9th to 3rd position. The greatest changes in DALYs were observed for road injuries dropping from 4th to 16th position, and congenital disorders from 17th to 35th; conversely, oral disorders rose from 25th to 17th. Overall, smoking is by far the most relevant risk factor in Spain, followed by high blood pressure, high body mass index, alcohol use, and high fasting plasma glucose. Finally, Spain scored 74.3 of 100 points in the SDG index classification in 2016, and the main national drivers of detrimental health in SDGs were alcohol consumption, smoking and child obesity. An increase to 80.3 points is projected in 2030. CONCLUSION: Low back and neck pain was the most important contributor of disability in Spain in 2016. There has seen a remarkable increase in the burden due to Alzheimer disease and other dementias. Tobacco remains the most important health issue to address in Spain.


Assuntos
Acidentes/estatística & dados numéricos , Doenças Transmissíveis/epidemiologia , Carga Global da Doença/estatística & dados numéricos , Doenças não Transmissíveis/epidemiologia , Acidentes de Trânsito/mortalidade , Dor nas Costas/epidemiologia , Causas de Morte , Pessoas com Deficiência/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Masculino , Cervicalgia/epidemiologia , Distúrbios Nutricionais/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Risco , Espanha/epidemiologia
19.
Sci Rep ; 7(1): 17383, 2017 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-29234107

RESUMO

Translesion DNA synthesis is an essential process that helps resume DNA replication at forks stalled near bulky adducts on the DNA. Benzo[a]pyrene (B[a]P) is a polycyclic aromatic hydrocarbon (PAH) that can be metabolically activated to benzo[a]pyrene diol epoxide (BPDE), which then can react with DNA to form carcinogenic DNA adducts. Here, we have used single-molecule florescence resonance energy transfer (smFRET) experiments, classical molecular dynamics simulations, and nucleotide incorporation assays to investigate the mechanism by which the model Y-family polymerase, Dpo4, bypasses a (+)-cis-B[a]P-N 2-dG adduct in DNA. Our data show that when (+)-cis-B[a]P-N 2-dG is the templating base, the B[a]P moiety is in a non-solvent exposed conformation stacked within the DNA helix, where it effectively blocks nucleotide incorporation across the adduct by Dpo4. However, when the media contains a small amount of dimethyl sulfoxide (DMSO), the adduct is able to move to a solvent-exposed conformation, which enables error-prone DNA replication past the adduct. When the primer terminates across from the adduct position, the addition of DMSO leads to the formation of an insertion complex capable of accurate nucleotide incorporation.


Assuntos
Benzo(a)pireno/metabolismo , Adutos de DNA/metabolismo , Reparo do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Simulação de Dinâmica Molecular , Sulfolobus solfataricus/enzimologia , Enzimas Reparadoras do DNA/metabolismo , Replicação do DNA
20.
Wellcome Open Res ; 2: 87, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29062917

RESUMO

Background: The human leukaemia virus HTLV-1 expresses essential accessory genes that manipulate the expression, splicing and transport of viral mRNAs.  Two of these genes, tax and hbz, also promote proliferation of the infected cell, and both genes are thought to contribute to oncogenesis in adult T-cell leukaemia/lymphoma.  The regulation of HTLV-1 proviral latency is not understood.  tax, on the proviral plus strand, is usually silent in freshly-isolated cells, whereas the minus-strand-encoded hbz gene is persistently expressed at a low level.  However, the persistently activated host immune response to Tax indicates frequent expression of tax in vivo.  Methods: We used single-molecule RNA-FISH to quantify the expression of HTLV-1 transcripts at the single-cell level in a total of >19,000 cells from five T-cell clones, naturally infected with HTLV-1, isolated by limiting dilution from peripheral blood of HTLV-1-infected subjects.  Results: We found strong heterogeneity both within and between clones in the expression of the proviral plus-strand (detected by hybridization to the tax gene) and the minus-strand ( hbz gene). Both genes are transcribed in bursts; tax expression is enhanced in the absence of hbz, while hbz expression increased in cells with high tax expression. Surprisingly, we found that hbz expression is strongly associated with the S and G 2/M phases of the cell cycle, independent of tax expression.  Contrary to current belief, hbz is not expressed in all cells at all times, even within one clone.  In hbz-positive cells, the abundance of hbz transcripts showed a very strong positive linear correlation with nuclear volume. Conclusions: The occurrence of intense, intermittent plus-strand gene bursts in independent primary HTLV-1-infected T-cell clones from unrelated individuals strongly suggests that the HTLV-1 plus-strand is expressed in bursts in vivo.  Our results offer an explanation for the paradoxical correlations observed between the host immune response and HTLV-1 transcription.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA