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1.
Rev Sci Instrum ; 94(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909838

RESUMO

LNG (Liquefied Natural Gas) has widely been used as an efficient and clean energy source. However, the storage and transportation of LNG is a big problem that the vacuum degree is difficult to measure in LNG pipeline transportation, especially without the vacuum test port. A measurement method for the vacuum degree of the LNG pipeline based on the second law of thermodynamics (the principle of temperature field) was proposed, and the vacuum degree of the pipeline was measured in this paper. The vacuum degree was obtained as a function of the ambient temperature T0 and the outer wall temperature T1 of the outer tube. The feasibility of this method was verified through test bench and field experiments, and the functional expressions of the outer wall temperature of the outer pipe and pipeline vacuum degree at 22, 24, and 26 °C were combined and verified, which provided a powerful way for measuring LNG pipeline vacuum.

2.
Plant Biotechnol J ; 21(4): 839-853, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36597709

RESUMO

Phased, small interfering RNAs (phasiRNAs) are important for plant anther development, especially for male sterility. PhasiRNA biogenesis is dependent on genes like RNA polymerase 6 (RDR6), DICER-LIKE 4 (DCL4), or DCL5 to produce 21- or 24 nucleotide (nt) double-strand small RNAs. Here, we generated mutants of DCL4, DCL5 and RDR6 using CRISPR/Cas9 system and studied their effects on plant reproductive development and phasiRNA production in wheat. We found that RDR6 mutation caused sever consequence throughout plant development starting from seed germination and the dcl4 mutants grew weaker with thorough male sterility, while dcl5 plants developed normally but exhibited male sterility. Correspondingly, DCL4 and DCL5, respectively, specified 21- and 24-nt phasiRNA biogenesis, while RDR6 contributed to both. Also, the three key genes evolved differently in wheat, with TaDCL5-A/B becoming non-functioning and TaRDR6-A being lost after polyploidization. Furthermore, we found that PHAS genes (phasiRNA precursors) identified via phasiRNAs diverged rapidly among sub-genomes of polyploid wheat. Despite no similarity being found among phasiRNAs of grasses, their targets were enriched for similar biological functions. In light of the important roles of phasiRNA pathways in gametophyte development, genetic dissection of the function of key genes may help generate male sterile lines suitable for hybrid wheat breeding.


Assuntos
Infertilidade Masculina , Triticum , Masculino , Humanos , Triticum/genética , Triticum/metabolismo , Sistemas CRISPR-Cas/genética , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Interferente Pequeno/genética , Mutagênese/genética , Plantas/genética , Infertilidade Masculina/genética , RNA de Plantas/genética , Regulação da Expressão Gênica de Plantas
3.
Plant J ; 108(3): 829-840, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34492155

RESUMO

High-molecular-weight glutenin subunits (HMW-GS) are major components of seed storage proteins (SSPs) and largely determine the processing properties of wheat (Triticum aestivum) flour. HMW-GS are encoded by the GLU-1 loci and regulated at the transcriptional level by interaction between cis-elements and transcription factors (TFs). We recently validated the function of conserved cis-regulatory modules (CCRMs) in GLU-1 promoters, but their interacting TFs remained uncharacterized. Here we identified a CCRM-binding NAM-ATAF-CUC (NAC) protein, TaNAC100, through yeast one-hybrid (Y1H) library screening. Transactivation assays demonstrated that TaNAC100 could bind to the GLU-1 promoters and repress their transcription activity in tobacco (Nicotiana benthamiana). Overexpression of TaNAC100 in wheat significantly reduced the contents of HMW-GS and other SSPs as well as total seed protein. This was confirmed by transcriptome analyses. Conversely, enhanced expression of TaNAC100 increased seed starch contents and expression of key starch synthesis-related genes, such as TaGBSS1 and TaSUS2. Y1H assays also indicated TaNAC100 binding with the promoters of TaGBSS1 and TaSUS2. These results suggest that TaNAC100 functions as a hub controlling seed protein and starch synthesis. Phenotypic analyses showed that TaNAC100 overexpression repressed plant height, increased heading date, and promoted seed size and thousand kernel weight. We also investigated sequence variations in a panel of cultivars, but did not identify significant association of TaNAC100 haplotypes with agronomic traits. The findings not only uncover a useful gene for wheat breeding but also provide an entry point to reveal the mechanism underlying metabolic balance of seed storage products.


Assuntos
Proteínas de Plantas/genética , Sementes/metabolismo , Amido/biossíntese , Triticum/fisiologia , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Pleiotropia Genética , Haplótipos , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Proteínas de Armazenamento de Sementes/genética , Proteínas de Armazenamento de Sementes/metabolismo , Sementes/genética , Amido/genética
4.
BMC Genomics ; 21(1): 200, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131726

RESUMO

BACKGROUND: PhasiRNAs (phased secondary siRNAs) play important regulatory roles in the development processes and biotic or abiotic stresses in plants. Some of phasiRNAs involve in the reproductive development in grasses, which include two categories, 21-nt (nucleotide) and 24-nt phasiRNAs. They are triggered by miR2118 and miR2275 respectively, in premeiotic and meiotic anthers of rice, maize and other grass species. Wheat (Triticum aestivum) with three closely related subgenomes (subA, subB and subD), is a model of allopolyploid in plants. Knowledge about the role of phasiRNAs in the inflorescence development of wheat is absent until now, and the evolution of PHAS loci in polyploid plants is also unavailable. RESULTS: Using 261 small RNA expression datasets from various tissues, a batch of PHAS (phasiRNA precursors) loci were identified in the young spike of wheat, most of which were regulated by miR2118 and miR2275 in their target site regions. Dissection of PHAS and their trigger miRNAs among the diploid (AA and DD), tetraploid (AABB) and hexaploid (AABBDD) genomes of Triticum indicated that distribution of PHAS loci were dominant randomly in local chromosomes, while miR2118 was dominant only in the subB genome. The diversity of PHAS loci in the three subgenomes of wheat and their progenitor genomes (AA, DD and AABB) suggested that they originated or diverged at least before the occurrence of the tetraploid AABB genome. The positive correlation between the PHAS loci or the trigger miRNAs and the ploidy of genome indicated the expansion of genome was the major drive force for the increase of PHAS loci and their trigger miRNAs in Triticum. In addition, the expression profiles of the PHAS transcripts suggested they responded to abiotic stresses such as cold stress in wheat. CONCLUSIONS: Altogether, non-coding phasiRNAs are conserved transcriptional regulators that display quick plasticity in Triticum genome. They may be involved in reproductive development and abiotic stress in wheat. It could be referred to molecular research on male reproductive development in Triticum.


Assuntos
MicroRNAs/genética , RNA Interferente Pequeno/genética , Triticum/crescimento & desenvolvimento , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Poliploidia , RNA de Plantas/genética , Triticum/genética
5.
Acta Diabetol ; 54(6): 569-579, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28341960

RESUMO

AIMS: This subanalysis of a cross-sectional, nationwide study was undertaken to assess the relationship between healthy lifestyle behaviors and multiple cardiovascular risk factors among people with type 2 diabetes mellitus (T2DM). METHODS: Data collected from 25,454 participants, including demographics, lifestyle behaviors and cardiovascular risk profiles, were analyzed. Blood pressure control as well as blood glucose and blood lipid (3Bs) levels were measured as multi-risk factors for cardiovascular disease. Healthy lifestyle behaviors included regular exercise, nonsmoking status and no alcohol consumption. The relationship between the healthy lifestyle behavior(s) and control of 3B(s) was calculated. RESULTS: Of the 25,454 eligible participants, 4171 (16.4%) were current smokers, 2011 (7.9%) currently consumed alcohol, and 11,174 (43.9%) did not exercise. In total, 654 (2.6%) reported all three unhealthy lifestyle behaviors. Most participants (71.1%) had received at least a high school education and were more likely to smoke and drink as compared to those with lower education. Unhealthy lifestyle behaviors were commonly found in participants with low atherosclerosis risk, such as non-elderly people and those with an above-college education level. Unhealthy lifestyle is associated with poor 3B control and worse medication adherence. CONCLUSIONS: Unhealthy lifestyles are common in Chinese people with T2DM, especially in people who are non-elderly and above-college educated. Interventions aimed at changing risky lifestyle behaviors are required for improved outcomes for Chinese patients with T2DM.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Estilo de Vida Saudável/fisiologia , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Povo Asiático/estatística & dados numéricos , Glicemia/análise , Pressão Sanguínea , Doenças Cardiovasculares/etiologia , China/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Exercício Físico/fisiologia , Feminino , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia
6.
Atherosclerosis ; 237(1): 99-105, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25238215

RESUMO

OBJECTIVE: To objectively evaluate lipid-lowering therapy and low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) goal attainment in metabolic syndrome (MetS) patients in China. METHODS: Data regarding patient demographics, lipid-lowering agents, lipid parameters, and cardiovascular risk profiles were analyzed for 25,317 patients of the Dyslipidemia International Study-China. MetS was defined according to criteria of the NCEP-ATP III and the 2007 Chinese Guidelines on Prevention and Treatment of Dyslipidemia in Adults. RESULTS: The prevalence of MetS was 39.9% and 37.4% according to the NCEP-ATP III and 2007 Chinese Guidelines, respectively. LDL-C goal attainment occurred less frequently among MetS patients than in those without MetS (NCEP-ATP III: 46.9% vs 68.6%; 2007 Chinese Guidelines: 52.2% vs 67.1%; p < 0.001). Similar results were obtained for non-HDL-C goal attainment (2007 Chinese Guidelines: 51.0% vs 72.0%; p < 0.001). As the risk class increased, LDL-C and non-HDL-C goal attainment decreased. In multivariate logistic regression analysis, DM, CHD, ischemic cerebrovascular disease, and higher SBP were independently associated with failure to achieve LDL-C and non-HDL-C goal attainment. The type of lipid-lowering agent was not significantly correlated with LDL-C not at goal attainment but was correlated with non-HDL-C not at goal attainment. CONCLUSION: Goal attainment for both LDL-C and non-HDL-C occurs less frequently in MetS patients than in those without MetS. The residual risk due to elevated non-HDL-C levels should be considered in MetS patients. Strategies for controlling multiple risk factors in order to decrease the residual risk related to dyslipidemia in MetS patients should be recommended in future guidelines.


Assuntos
Anticolesterolemiantes/uso terapêutico , Dislipidemias/epidemiologia , Lipídeos/sangue , Síndrome Metabólica/sangue , Idoso , Antropometria , Doenças Cardiovasculares/sangue , China , LDL-Colesterol/sangue , Estudos Transversais , Complicações do Diabetes/sangue , Dislipidemias/tratamento farmacológico , Dislipidemias/etnologia , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Prevalência , Análise de Regressão , Fatores de Risco , Fumar
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