Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31.221
Filtrar
1.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-LISBR1.1-47414

RESUMO

A ACT Promoção da Saúde e outras organizações assinam nota conjunta sobre estudo que sugeriu um suposto efeito protetor da nicotina no combate ao COVID-19. A nota destaca que o estudo em questão não foi revisado por pares e que ao menos um dos autores do estudo já foi financiado no passado pela indústria do tabaco.


Assuntos
Tabagismo , Tabaco , Vírus da SARS , Coronavirus , Nicotina
2.
Pestic Biochem Physiol ; 165: 104523, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359551

RESUMO

Tobacco black shank (TBS) caused by Phytophthora nicotianae is destructive to almost all tobacco cultivars and is widespread in many tobacco-growing countries. Through lab study and field test, we isolated plant growth-promoting rhizobacteria (PGPR) strain Ba168 which is a promising biocontrol strain of TBS. Ba168 was isolated from 168 soil samples and identified as Bacillus velezensis by its genetic and phenotypic characteristics. A susceptibility test indicated that the P. nicotianae antagonistic materials of Ba168 in extracellular metabolites were composed of effective and stable proteins/peptides. P. nicotianae's growth was suppressed by the ammonium sulfate precipitation of Ba168 culture filtrates (ASPBa) at a minimum inhibitory concentration of 5 µg/mL. Extracellular conductivity, pH, and the wet/dry weights of P. nicotianae's mycelia, along with scanning electron microscope analysis, suggested that Ba168-derived proteins/peptides could effectively inhibit P. nicotianae by causing irreversible damage to its cell walls and membranes. Protein identification of ASPBa supported these results and identified many key proteins responsible for various biocontrol-related pathways. Field assays of TBS control efficacy of many PGPRs and agrochemicals showed that all PGPR preparations reduced the disease index of tobacco, but Ba168 was the most effective. These results demonstrated the importance of Bacillus-derived proteins/peptides in the inhibition of P. nicotianae through irreversible damage to its cell wall and membrane; and the effectiveness of PGPR strain B. velezensis Ba168 for biocontrol of the soil-borne disease caused by P. nicotianae.


Assuntos
Bacillus , Phytophthora , Doenças das Plantas , Tabaco
4.
Sheng Wu Gong Cheng Xue Bao ; 36(4): 700-706, 2020 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-32347064

RESUMO

The responsibility of root is absorbing water and nutrients, it is an important plant tissue, but easily to be affected by biotic and abiotic stresses, affecting crop growth and yield. The design of a synthetic root-specific promoter provides candidate promoters for the functional analysis and efficient expression of stress-related genes in crop roots. In this study, a synthetic root-specific module (pro-SRS) was designed using tandem four-copies of root specific cis-acting elements (OSE1ROOTNODULE, OSE2ROOTNODULE, SP8BFIBSP8AIB, and ROOTMOTIFAPOX1), and fused with minimal promoter from the CaMV 35S promoter to synthesize an artificially synthetic SRSP promoter. The SRSP promoter was cloned in pCAMBIA2300.1 by replacing CaMV 35S promoter so as to drive GUS expression. The constructs with SRSP promoter were transformed in tobacco by Agrobacterium-mediated method. SRSP promoter conferred root-specific expression in transgenic tobacco plants through Real-time PCR (RT-PCR) analysis and GUS histochemical staining analysis. It is indicated that the repeated arrangement of cis-acting elements can realize the expected function of the promoter. This study laid a theoretical foundation for the rational design of tissue-specific promoters.


Assuntos
Regulação da Expressão Gênica de Plantas , Raízes de Plantas , Regiões Promotoras Genéticas , Tabaco , Agrobacterium/genética , Clonagem Molecular , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Estresse Fisiológico , Tabaco/genética , Tabaco/crescimento & desenvolvimento , Transformação Genética
5.
Pestic Biochem Physiol ; 164: 40-46, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32284135

RESUMO

Plant viral diseases cause severe economic losses in agricultural production. Development of microorganism-derived antiviral agents provides an alternative strategy to efficiently control plant viral diseases. In this study, the antiviral effect and mechanism of a combined biological agent Cytosinpeptidemycin and Chitosan oligosaccharide (CytPM-COS) were investigated. CytPM-COS effectively inhibited tobacco mosaic virus (TMV) in Nicotiana glutinosa, suppressed viral RNA and CP accumulation in BY-2 protoplast and affected the subcellular localization as well as punctate formation of TMV MP in N. benthamiana leaves. In addition, CytPM-COS triggered reactive oxygen species (ROS) production and induced up-regulation of various defense responsive genes including PR-1, PR-5, FLS2, Hsp70. Our results indicated that CytPM-COS can potentially act as a pesticide for integrated control of plant viruses in the future.


Assuntos
Antivirais , Quitosana , Vírus do Mosaico do Tabaco , Fatores Biológicos , Citosina/análogos & derivados , Oligossacarídeos , Doenças das Plantas , Folhas de Planta , Tabaco
6.
Gene ; 741: 144522, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32145329

RESUMO

Virus-induced gene silencing (VIGS) is a transient based reverse genetic tool used to elucidate the function of novel gene in N. benthamiana. In current study, 14 UDP-D-glucuronate 4-epimerase (GAE) family members were identified and their gene structure, phylogeny and expression pattern were analyzed. VIGS system was optimized for the functional characterization of NbGAE6 homologous genes in N. benthamiana. Whilst the GAE family is well-known for the interconversion of UDP-D-GlcA and UDP-D-GalA during pectin synthesis. Our results revealed that the downregulation of these genes significantly reduced the amount of GalA in the homogalacturunan which is the major component of pectin found in primary cell wall. Biphenyl assay and high performance liquid chromatography analysis (HPLC) depicted that the level of 'GalA' monosaccharide reduced to 40-51% in VIGS plants as compared to the wild type plants. Moreover, qRT-PCR also confirmed the downregulation of the NbGAE6 mRNA in VIGS plants. In all, this is the first comprehensive study of the optimization of VIGS system for the provision of rapid silencing of GAE family members in N. benthamiana, eliminating the need of stable transformants.


Assuntos
Proteínas de Arabidopsis/genética , Carboidratos Epimerases/genética , Parede Celular/metabolismo , Pectinas/genética , Tabaco/genética , Arabidopsis/genética , Parede Celular/genética , Parede Celular/virologia , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Vetores Genéticos/genética , Monossacarídeos/metabolismo , Pectinas/biossíntese , Peptídeos , Vírus de Plantas/genética , RNA Mensageiro/genética , Tabaco/virologia
8.
Med Sci Monit ; 26: e920793, 2020 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-32201430

RESUMO

BACKGROUND Chronic obstructive pulmonary disease (COPD), a general airway disease, is featured by progressive and chronic immunoreaction in the lung. Increasing evidences have showed that cigarette smoking is the main reason in the COPD progression, and human pulmonary microvascular endothelial cell (HPMEC) apoptosis often be observed in COPD, while its pathogenesis is not yet fully described. Upregulation of long noncoding RNA (lncRNA) maternally expressed gene 3 (MEG3) was observed in COPD patients, but the specific mechanism of lncRNA MEG3 in COPD remains unknown. The objective of this research was to explore the role of lncRNA MEG3 in cigarette smoke extract (CSE)-induced HPMECs. MATERIAL AND METHODS HPMECs were induced by a series of concentrations of CSE (0%, 0.1%, 1%, and 10%). Then cell apoptosis was analyzed by flow cytometry. Cell apoptosis related proteins were tested using western blot assay. Finally, we applied knockdown and over-expression system to explore the lncRNA MEG3 functions in CSE-induced HPMECs. RESULTS Our results indicated that various concentrations of CSE (0%, 0.1%, 1%, and 10%) significantly promoted cell apoptosis, augmented caspase-3 activity, upregulated Bax expression, decreased Bcl-2 expression, and enhanced lncRNA MEG3 level in HPMECs. LncRNA MEG3-plasmid transfection resulted in the upregulation of lncRNA MEG3, more apoptotic HPMECs, and higher caspase-3 activity. While lncRNA MEG3 knockdown presented the opposite effects. Further investigation suggested that all the effects of CSE treatment on HPMECs were markedly reversed by lncRNA MEG3-shRNA (short hairpin RNA). CONCLUSIONS Our study illustrated a protective effect of lncRNA MEG3-shRNA on CSE-induced HPMECs, indicting lncRNA MEG3 can be a new therapeutic approach for COPD treatment.


Assuntos
Doença Pulmonar Obstrutiva Crônica/metabolismo , RNA Longo não Codificante , Transdução de Sinais/fisiologia , Tabaco/efeitos adversos , Apoptose/fisiologia , Células Cultivadas , Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Fumaça/efeitos adversos
9.
Asian Pac J Cancer Prev ; 21(3): 667-673, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32212792

RESUMO

BACKGROUND: Lung cancer coexisting with idiopathic pulmonary fibrosis (IPF) or chronic obstructive pulmonary disease (COPD) can lead to poor prognosis.  Telomere-related polymorphisms may be implicated in the pathogenesis of these three lung diseases.  As to elucidate the mechanism of lung cancer via IPF or COPD may enable early detection and early treatment of the disease, we firstly examined the association between telomere-related polymorphisms and the risk of IPF and COPD in a case-control study. MATERIALS AND METHODS: A total of 572 patients with IPF (n = 155) or COPD (n = 417), who were derived from our on-going cohort study, and controls (n = 379), who were derived from our previous case-control study, were included in this study.  Telomerase reverse transcriptase (TERT) rs2736100, telomere RNA component (TERC) rs1881984, and oligonucleotide/oligosaccharide-binding fold containing1 (OBFC1) rs11191865 were genotyped with real-time PCR using TaqMan fluorescent probes. Unconditional logistic regression was used to assess the adjusted odds ratios and 95% confidence intervals. RESULTS: TERT rs2736100 was significantly associated with the risk of IPF; increases in the number of this risk allele increased the risk of IPF (Ptrend = 0.008).  Similarly, TERT rs2736100 was associated with the risk of COPD.  In regard to the combined action of the three loci, increasing numbers of "at-risk" genotypes increased the risk of IPF in a dose-dependent manner (P trend=0.003). CONCLUSIONS: TERT rs2736100 was associated with the risks of both IPF and COPD in a Japanese population. A combination of the "at-risk" genotypes might be important to identify the population at risk for IPF more clearly.


Assuntos
Fibrose Pulmonar Idiopática/genética , Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Doença Pulmonar Obstrutiva Crônica/genética , Telomerase/genética , Feminino , Humanos , Masculino , Sistema de Registros , Fatores de Risco , Tabaco/efeitos adversos
10.
Washington, D.C.; PAHO; 2020-03-27. (PAHO/NMH/20-0004).
em Inglês | PAHO-IRIS | ID: phr-51952

RESUMO

This scorecard has been developed by PAHO to highlight the country capacity for noncommunicable diseases and showcase regional results from the global NCD Progress Monitor 2020. It provides a snapshot of key NCD indicators across all countries in the Region of the Americas, and complements the country profiles published on the WHO 2020 Progress Monitor for Noncommunicable Diseases. The tool aims to promote understanding of the response to NCDs and assist decision-making for NCD program improvement. The WHO Progress Monitor 2020 for Noncommunicable Diseases (NCDs), the third of a series, provides information on the country capacity for NCDs, measured by the 19 indicators on NCDs. They include setting time-bound targets to reduce NCD deaths; developing all-of-government policies to address NCDs; implementing key tobacco demand reduction measures, measures to reduce harmful use of alcohol and unhealthy diets and promote physical activity; and strengthening health systems through primary health care and universal health coverage. Noncommunicable diseases (NCDs) and their risk factors are the leading causes of morbidity, mortality, and disability in the Americas, and they represent both a public health challenge and a serious threat to economic and social development. In the Region of the Americas, NCDs cause approximately 5.5 million deaths per year, representing 80.7% of all deaths in the region. Of the total deaths from NCDs, 38.9% are premature deaths occurring in people under 70 years of age.


Assuntos
Doenças não Transmissíveis , Vigilância , Aptidão Física , Ambientes Livres de Fumo , Tabaco , Consumo de Bebidas Alcoólicas , Dieta Saudável , Programas e Políticas de Nutrição e Alimentação , Política Antifumo , Política Ambiental
11.
Plant Mol Biol ; 103(1-2): 185-196, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124178

RESUMO

As a key integrator of shoot branching, BRANCHED 1 (BRC1) coordinates and is orchestrated by endogenous and environmental signals involved in the regulation of axillary bud outgrowth. In the present study, we characterized the regulatory roles of five BRC gene members in tobacco (Nicotiana tabacum L.) using CRISPR site-directed mutagenesis and overexpression assays. It was shown that lateral branching was negatively regulated by NtBRC1A-1, 1B-1, and 1B-2, but was unexpectedly promoted by NtBRC2A. Suppression of bud growth may be attained by direct binding of NtBRCs to the Tassels Replace Upper Ears 1 (TRU1) genes. It was speculated that NtBRC2A probably confers a dominant negative effect by interfering with the branching-inhibitory BRC1 genes. Our results suggested that highly homologous gene family members may function antagonistically in the same signaling pathway. However, the molecular mechanism underlying NtBRC2A-mediated outgrowth of axillary buds needs to be further addressed. KEY MESSAGE: Axillary bud outgrowth in general is negatively regulated by the BRANCHED gene. Here we show that the BRANCHED genes play opposing regulatory roles in tobacco lateral branching.


Assuntos
Genes de Plantas , Desenvolvimento Vegetal/genética , Tabaco/crescimento & desenvolvimento , Sistemas CRISPR-Cas , Regulação para Baixo , Regulação da Expressão Gênica de Plantas , Filogenia , Interferência de RNA , Transdução de Sinais , Tabaco/genética , Transcriptoma , Regulação para Cima
12.
Nat Rev Cancer ; 20(4): 199, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32112043
15.
PLoS One ; 15(2): e0229256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084204

RESUMO

Cigarette smoke (CS) contains multiple gaseous and particulate materials that can cause lung inflammation, and smoking is the major cause of chronic obstructive pulmonary disease (COPD). We sought to determine the mechanisms of how CS triggers lung inflammation. Nur77, a nuclear hormone receptor belonging to the immediate-early response gene family, controls inflammatory responses, mainly by suppressing the NF-κB signaling pathway. Because it is unknown if Nur77's anti-inflammatory role modulates COPD, we assessed if and how Nur77 expression and activity are altered in CS-induced airway inflammation. In lung tissues and bronchial epithelial cells from COPD patients, we found Nur77 was downregulated. In a murine model of CS-induced airway inflammation, CS promoted lung inflammation and also reduced Nur77 activity in wild type (WT) mice, whereas lungs of Nur77-deficient mice showed exaggerated CS-induced inflammatory responses. Our findings in in vitro studies of human airway epithelial cells complemented those in vivo data in mice, together showing that CS induced threonine-phosphorylation of Nur77, which is known to interfere with its anti-inflammatory functions. In summary, our findings point to Nur77 as an important regulator of CS-induced inflammatory responses and support the potential benefits of Nur77 activation for COPD treatment.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Doença Pulmonar Obstrutiva Crônica/genética , Fumaça/efeitos adversos , Tabaco/química , Animais , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Inflamação/genética , Pulmão/patologia , Camundongos , Fosforilação/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/patologia , Treonina/metabolismo
16.
Sci Total Environ ; 711: 135028, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000334

RESUMO

Telomere length and mitochondrial DNA content are considered biomarkers of cellular aging, oxidative stress, and inflammation, but there is almost no information on their association with tobacco smoke exposure in fetal and early life. The aim of this study was to assess whether prenatal and childhood tobacco exposure were associated with leukocyte telomere length (LTL) and mitochondrial DNA (mtDNA) content in children. As part of a multi-centre European birth cohort study HELIX (Human Early-Life Exposome) (n = 1396) we assessed maternal smoking status during pregnancy through questionnaires, and through urinary cotinine levels that were then used to classify women as not exposed to smoking (<10 µg/L), exposed to secondhand smoke (SHS) (10-50 µg/L) and active smokers (>50 µg/L). When the children were around 8 years of age (range: 5.4-12.0 years), childhood SHS tobacco smoke exposure was assessed through an extensive questionnaire and through measurements of urinary cotinine (<3.03 µg/L non-detected, >3.03 µg/L detected). Leukocyte mtDNA content and LTL were measured in the children at 8 years employing real time polymerase chain reaction (qPCR). Effect estimates were calculated using multivariate linear regression models for prenatal and childhood exposures adjusted for potential confounders. Maternal cotinine levels indicative of SHS exposure during pregnancy were associated with a decrease of 3.90% in LTL in children (95% CI: -6.68, -0.91), compared with non-smoking, whereas the association for maternal cotinine levels indicative of active smoking did not reach statistical significance (-3.24%; 95% CI: -6.59, 0.21). Childhood SHS tobacco exposure was not associated with LTL in children. Global SHS exposure during childhood was associated with an increase of 3.51% (95% CI: 0.78, 6.27) in mtDNA content. Our findings suggest that tobacco smoke exposure during pregnancy, even at SHS levels, may accelerate telomere shortening in children and thus induce biological aging from an early age.


Assuntos
Tabaco , Criança , Pré-Escolar , Estudos de Coortes , Cotinina , Feminino , Humanos , Gravidez , Telômero , Poluição por Fumaça de Tabaco
17.
Nat Commun ; 11(1): 725, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024833

RESUMO

The rice orthologue of maize domestication gene Teosinte branched 1 (Tb1) affects tillering. But, unlike maize Tb1 gene, it was not selected during domestication. Here, we report that an OsTb1 duplicate gene (OsTb2) has been artificially selected during upland rice adaptation and that natural variation in OsTb2 is associated with tiller number. Interestingly, transgenic rice overexpressing this gene shows increased rather than decreased tillering, suggesting that OsTb2 gains a regulatory effect opposite to that of OsTb1 following duplication. Functional analyses suggest that the OsTb2 protein positively regulates tillering by interacting with the homologous OsTb1 protein and counteracts the inhibitory effect of OsTb1 on tillering. We further characterize two functional variations within OsTb2 that regulate protein function and gene expression, respectively. These results not only present an example of neo-functionalization that generates an opposite function following duplication but also suggest that the Tb1 homologue has been selected in upland rice.


Assuntos
Oryza/fisiologia , Proteínas de Plantas/genética , Adaptação Biológica , Irrigação Agrícola , Evolução Molecular , Duplicação Gênica , Regulação da Expressão Gênica de Plantas , Mutação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Tabaco/genética
18.
Sci Total Environ ; 714: 136700, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32028551

RESUMO

The leaching behavior of Al, Cr, Ni, Cu, Zn, As, Se, Cd, Ba, Hg and Pb in water from two types of heat-not-burn tobacco sticks is presented here, and compared to that from conventional cigarettes. The total concentration of each metal in solid tobacco products was initially determined. Concentrations in used and unused tobacco sticks were similar and generally, lower than those in unused conventional cigarettes. Studies on the contribution of paper, filter and tobacco revealed that tobacco was the major source of metal contamination. Smoking conventional cigarettes reduced the total metal concentrations since a substantial amount of metals was retained in the ash; a post-consumption waste that is difficult to collect. Batch leaching tests were performed to determine dissolved concentrations as a function of time. With the exceptions of As and (in most cases) Hg that were not detected, metals were released at varying rates. At 24 h of soaking the percentage of metals leached ranged from 0.2-43%. The contribution of paper, filter and tobacco to the dissolved concentrations at 24 h of leaching was investigated and in almost all cases tobacco was the major source of metal contamination. The dissolved concentrations from ash were low as metals were strongly bound. Varying the pH, ionic strength and humic acids content at environmentally relevant values did not affect leaching of metals at 24 h of soaking. The use of river water, rain water and seawater as leachants was also not found to alter dissolved concentrations at 24 h compared to ultrapure water. The results presented here suggest that the consequences of improper disposal of tobacco products in the environment are two-sided and that next to the generation of plastic litter, discarded tobacco products can also act as point sources of metal contamination. Public education campaigns focusing on the environmental impact and best disposal practices are urgently needed.


Assuntos
Produtos do Tabaco , Água Doce , Temperatura Alta , Metais , Tabaco
19.
Cell Host Microbe ; 27(3): 405-417.e6, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32101702

RESUMO

In certain plant hybrids, immunity signaling is initiated when immune components interact in the absence of a pathogen trigger. In Arabidopsis thaliana, such autoimmunity and cell death are linked to variants of the NLR RPP7 and the RPW8 proteins involved in broad-spectrum resistance. We uncover the molecular basis for this autoimmunity and demonstrate that a homolog of RPW8, HR4Fei-0, can trigger the assembly of a higher-order RPP7 complex, with autoimmunity signaling as a consequence. HR4Fei-0-mediated RPP7 oligomerization occurs via the RPP7 C-terminal leucine-rich repeat (LRR) domain and ATP-binding P-loop. RPP7 forms a higher-order complex only in the presence of HR4Fei-0 and not with the standard HR4 variant, which is distinguished from HR4Fei-0 by length variation in C-terminal repeats. Additionally, HR4Fei-0 can independently form self-oligomers, which directly kill cells in an RPP7-independent manner. Our work provides evidence for a plant resistosome complex and the mechanisms by which RPW8/HR proteins trigger cell death.


Assuntos
Proteínas de Arabidopsis/imunologia , Arabidopsis/imunologia , Morte Celular , Imunidade Vegetal , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Multimerização Proteica , Tabaco/imunologia
20.
Nature ; 578(7794): 224-226, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32042085
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA