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1.
Front Genet ; 13: 850201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401668

RESUMO

The genus Thuniopsis was recently proposed for a rare orchid species T. cleistogama formerly classified in the genus Thunia. The relationships between Thuniopsis and its related genera have not yet been conclusively resolved. Recognition of the genus provides a new perspective to illustrate the morphological diversity and plastome evolution within Coelogyninae. In this study, we sequenced and assembled complete chloroplast (cp) genomes for three accessions of Thuniopsis cleistogama and two accessions of Thunia alba. A total of 135 genes were annotated for each cp genome, including 89 protein-coding genes, 38 tRNA genes, and eight rRNA genes. The ENC-plot and neutrality plot analyses revealed that natural selection dominated over mutation pressure in their evolutionary process. Specially, we found that selection played a vital role in shaping the codon usage in Thunia alba cp genome. General characteristics of the cp genomes were further analyzed and compared with those published plastomes of four other related species. Despite the conserved organization and structure, the whole individual cp genome size ranged from 158,394 bp to 159,950 bp. In all the examined plastomes, sequences in the inverted repeat (IR) regions were more conserved than those in the small single copy (SSC) and large single copy (LSC) regions. However, close examination identified contraction and expansion of the IR/SSC boundary regions, which might be the main reason for the cp genome size variation. Our comparative analysis of the cp genomes revealed that single nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) provided valuable information for identifying genetic variations within and among genera. Furthermore, sequence variations in the protein-coding regions were more conserved than those in the non-coding regions. We selected eight divergence hotspots with nucleotide sequence diversities (Pi values) higher than 0.08. Most of these polymorphisms were located in the intergenic regions. Phylogenomic analyses recovered largely congruent relationships among major clades and strongly supported the monophyly of Thuniopsis. The results obtained in this study can improve our understanding of the classification of this enigmatic genus. The chloroplast genomic data presented here provide valuable insights into the phylogeny and evolutionary patterns of the Coelogyninae as well as the orchids as a whole.

2.
Mitochondrial DNA B Resour ; 7(4): 593-595, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386637

RESUMO

Actinidia chinensis Planch. 'Hongyang' Wu and Li 1993, also known as red-fleshed kiwifruit, has a high vitamin C content and with high economic and nutritional value. Here, we assembled the complete chloroplast genome of A. chinensis Planch. 'Hongyang', which was 156,267 bp in length, contained a large single-copy region (LSC) of 87,866 bp, a small single-copy region (SSC) of 20,335 bp, and two inverted repeat (IR) regions of 24,033 bp. In addition, the chloroplast genome contained 132 genes, including 85 protein-coding, 39 tRNA, and eight rRNA genes. Overall GC content in the genome was 37.2%, with the corresponding values in the LSC, SSC, and IR regions of 35.5%, 31.1%, and 42.9%, respectively. Phylogenetic analysis indicated that A. chinensis Planch. 'Hongyang' was clustered with that of A. callosa var. strigillosa, A. deliciosa, A. melanandra, A. chinensis and A. setosa in the same branch.

3.
Food Chem ; 387: 132895, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35413551

RESUMO

Resistant starches (RS), which are considered as one of the dietary fibers, could exert widely beneficial impacts, reduce fat accumulation, show significant effects on regulating blood glucose metabolism and insulin levels, and have protective effects on the gut. Five types of RS have different responses to chronic disease by modulating gut microbiota. Short-chain fatty acids are the linkage between gut microbiota and RS, and RS could improve the metabolism of gut microbiota as well as increase the abundance of beneficial microbes in the gut. The composition of gut microbiota is associated with RS properties, which is reflected by the changes of butyrate-producing bacteria primarily influenced by consumption of RS with various fine structures and types of crystallinities. RS with different fine structures and properties is consumed to varying degrees by gut microbiota, which can be applied to produce functional foods for gut health in future.


Assuntos
Microbioma Gastrointestinal , Amido Resistente , Fibras na Dieta , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/fisiologia , Amido/metabolismo
4.
Food Chem ; 374: 131586, 2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-34839969

RESUMO

Various structural types of polysaccharides are recognized by toll-like receptor 4 (TLR4). However, the mechanism of interaction between the polysaccharides with different structures and TLR4 is unclarified. This review summarized the primary structure of polysaccharides related to TLR4, mainly including molecular weight, monosaccharide composition, glycosidic bonds, functional groups, and branched-chain structure. The optimal primary structure for interacting with TLR4 was obtained by the statistical analysis. Besides, the dual-directional regulation of TLR4 signaling cascade by polysaccharides was also elucidated from an immune balance perspective. Finally, the 3D interaction model of polysaccharides to TLR4-myeloid differentiation factor 2 (MD2) complex was hypothesized according to the LPS-TLR4-MD2 dimerization model and the polysaccharides solution conformation. The essence of polysaccharides binding to TLR4-MD2 complex is a multivalent non-covalent bond interaction. All the arguments summarized in this review are intended to provide some new insights into the interaction between polysaccharides and TLR4.


Assuntos
Antígeno 96 de Linfócito , Receptor 4 Toll-Like , Lipopolissacarídeos , Antígeno 96 de Linfócito/metabolismo , Polissacarídeos , Transdução de Sinais , Receptor 4 Toll-Like/metabolismo
5.
Front Genet ; 12: 744220, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899836

RESUMO

NAC (NAM, ATAF1/2, and CUC2) proteins play a pivotal role in modulating plant development and offer protection against biotic and abiotic stresses. Until now, no systematic knowledge of NAC family genes is available for the food security crop, sweet potato. Here, a comprehensive genome-wide survey of NAC domain-containing proteins identified 130 ItbNAC and 144 ItfNAC genes with full length sequences in the genomes of two diploid wild relatives of cultivated sweet potato, Ipomoea triloba and Ipomoea trifida, respectively. These genes were physically mapped onto 15 I. triloba and 16 I. trifida chromosomes, respectively. Phylogenetic analysis divided all 274 NAC proteins into 20 subgroups together with NAC transcription factors (TFs) from Arabidopsis. There were 9 and 15 tandem duplication events in the I. triloba and I. trifida genomes, respectively, indicating an important role of tandem duplication in sweet potato gene expansion and evolution. Moreover, synteny analysis suggested that most NAC genes in the two diploid sweet potato species had a similar origin and evolutionary process. Gene expression patterns based on RNA-Seq data in different tissues and in response to various hormone, biotic or abiotic treatments revealed their possible involvement in organ development and response to various biotic/abiotic stresses. The expression of 36 NAC TFs, which were upregulated in the five tissues and in response to mannitol treatment, was also determined by real-time quantitative polymerase chain reaction (RT-qPCR) in hexaploid cultivated sweet potato exposed to drought stress. Those results largely corroborated the expression profile of mannitol treatment uncovered by the RNA-Seq data. Some significantly up-regulated genes related to drought stress, such as ItbNAC110, ItbNAC114, ItfNAC15, ItfNAC28, and especially ItfNAC62, which had a conservative spatial conformation with a closely related paralogous gene, ANAC019, may be potential candidate genes for a sweet potato drought tolerance breeding program. This analysis provides comprehensive and systematic information about NAC family genes in two diploid wild relatives of cultivated sweet potato, and will provide a blueprint for their functional characterization and exploitation to improve the tolerance of sweet potato to abiotic stresses.

6.
Rev. bras. med. esporte ; 27(3): 245-248, July-Sept. 2021. tab
Artigo em Inglês | LILACS | ID: biblio-1288572

RESUMO

ABSTRACT Introduction The research on the promotion of physical fitness of the human body by exercise has also attracted widespread attention in sports and rehabilitation medicine. Object This article uses ultrasound to study the bone density health of the human body, thereby establishing the relationship between sports and bone density health. We hope to use the research results of this article to improve people's awareness of sports health. Method We used ultrasound to test the bone mineral density of two groups of students (exercise group and non-exercise group) to explore the relationship between different sports items and the students' bone mineral density. Results There is a significant difference in bone density between the two groups of students. There is no gender difference in bone density. Conclusion Students need to strengthen physical exercise in the growth and development stage to improve bone density. Level of evidence II; Therapeutic studies - investigation of treatment results.


RESUMO Introdução A pesquisa sobre a promoção da aptidão física do corpo humano por meio do exercício também tem atraído atenção generalizada na medicina esportiva e de reabilitação. Objeto este artigo usa o ultrassom para estudar a saúde da densidade óssea do corpo humano, estabelecendo assim a relação entre esportes e saúde da densidade óssea. Esperamos usar os resultados da pesquisa deste artigo para aumentar a conscientização das pessoas sobre a saúde no esporte. Método Usamos ultrassom para testar a densidade mineral óssea de dois grupos de alunos (grupo de exercícios e grupo de não exercícios) para explorar a relação entre diferentes itens esportivos e a densidade mineral óssea dos alunos. Resultados Existe uma diferença significativa na densidade óssea entre os dois grupos de alunos. Não há diferença de gênero na densidade óssea. Conclusão Os alunos precisam fortalecer os exercícios físicos na fase de crescimento e desenvolvimento para melhorar a densidade óssea. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción La investigación sobre la promoción de la aptitud física del cuerpo humano mediante el ejercicio también ha atraído una amplia atención en la medicina deportiva y de rehabilitación. Objeto Este artículo utiliza la ecografía para estudiar la salud de la densidad ósea del cuerpo humano, estableciendo así la relación entre el deporte y la salud de la densidad ósea. Esperamos utilizar los resultados de la investigación de este artículo para mejorar la conciencia de las personas sobre la salud deportiva. Método Utilizamos ultrasonido para probar la densidad mineral ósea de dos grupos de estudiantes (grupo de ejercicio y grupo sin ejercicio) para explorar la relación entre diferentes artículos deportivos y la densidad mineral ósea de los estudiantes. Resultados Existe una diferencia significativa en la densidad ósea entre los dos grupos de estudiantes. No hay diferencia de género en la densidad ósea. Conclusión Los estudiantes necesitan fortalecer el ejercicio físico en la etapa de crecimiento y desarrollo para mejorar la densidad ósea. Nivel de evidencia II; Estudios terapéuticos: investigación de los resultados del tratamiento.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Esportes/fisiologia , Densidade Óssea/fisiologia , Saúde , Aptidão Física/fisiologia , Promoção da Saúde , Modelos Teóricos
7.
Sensors (Basel) ; 21(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062928

RESUMO

In this study, a novel piezoelectric energy harvester (PEH) based on the array composite spherical particle chain was constructed and explored in detail through simulation and experimental verification. The power test of the PEH based on array composite particle chains in the self-powered system was realized. Firstly, the model of PEH based on the composite spherical particle chain was constructed to theoretically realize the collection, transformation, and storage of impact energy, and the advantages of a composite particle chain in the field of piezoelectric energy harvesting were verified. Secondly, an experimental system was established to test the performance of the PEH, including the stability of the system under a continuous impact load, the power adjustment under different resistances, and the influence of the number of particle chains on the energy harvesting efficiency. Finally, a self-powered supply system was established with the PEH composed of three composite particle chains to realize the power supply of the microelectronic components. This paper presents a method of collecting impact energy based on particle chain structure, and lays an experimental foundation for the application of a composite particle chain in the field of piezoelectric energy harvesting.

8.
J Agric Food Chem ; 69(25): 7000-7015, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34139119

RESUMO

High intake of dietary fibers was found to be inversely associated with type-2 diabetes (T2D), whereas the difference among different dietary fibers on T2D remains unclear. Therefore, we have investigated the effects of different dietary fibers on T2D. Nine types of dietary fibers were used to investigate and evaluate their effects on type-2 diabetic rats via physiology, genomics, and metabolomics. We found that supplementation with ß-glucan, arabinogalactan, guar gum, apple pectin, glucomannan, and arabinoxylan significantly reduced the fasting blood glucose, whereas carrageenan, xylan, and xanthan gum did not affect glycemic control in diabetic rats. Also, bioactive dietary fibers (ß-glucan, arabinogalactan, guar gum, and apple pectin) associated with the increased butyric acid level and abundance of beneficial bacteria (Lachnobacterium, Parabacteroides, Faecalibacterium, Akkermansia, and some butyric acid-producing bacteria), as well as improved host metabolism by decreasing 12α-hydroxylated bile acids, acylcarnitines, and amino acids (leucine, phenylalanine, citrulline, etc.), thereby exert beneficial effects on T2D. It was also found that ß-glucan might attenuate insulin resistance via downregulation of Prevotella copri-mediated biosynthesis of branched-chain amino acids in T2D. Together, our study uncovered the effects of different dietary fibers on T2D, along with their potential mechanism.


Assuntos
Diabetes Mellitus Experimental , Microbioma Gastrointestinal , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Fibras na Dieta , Hipoglicemiantes , Prevotella , Ratos
9.
Food Funct ; 12(6): 2617-2630, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33634806

RESUMO

Obesity is a chronic disease characterized by overweight resulting from fat accumulation, along with disturbance of metabolism and gut microbiota. Fermentation, as a green processing method, is beneficial for improving the nutrition capacity of food components. Polysaccharides are considered as one of the important components in food and are also potential supplements for anti-obesity treatment. This study aimed to investigate the anti-obesity effects of polysaccharides from fermented and non-fermented Momordica charantia L. with Lactobacillus plantarum NCU116 (FP and NFP) on obese rats by serum metabolomics and gut microbiota analysis. Metabolomics results revealed that abnormal lipid metabolism was formed due to obesity. The supplement of FP and NFP improved the glycerophospholipids, glycosphingolipids, and amino acid metabolism of the obese rats, which alleviated the hypercholesterolemia and overweight in rats. Furthermore, the disorder of gut microbiota was ameliorated by FP and NFP. FP promoted the growth of beneficial bacteria, such as phylum Firmicutes, Actinobacteria, and genera Anaerostipes, Coprococcus, Lactobacillus, and Bifidobacterium. FP also reduced several harmful bacteria belonging to the phylum Proteobacteria and genera Helicobacter. The positive correlation of the weight loss and lowering of serum lipids with the increased beneficial bacteria further elucidated that the anti-obesity effect of FP in obese rats is associated with the regulation of gut microbiota and serum metabolites. The results of this study could provide information for developing probiotic products in the future that may have beneficial effects on the prevention or treatment of obesity.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Lactobacillus plantarum , Momordica charantia/química , Polissacarídeos/farmacologia , Probióticos/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Fermentação , Lipídeos/sangue , Masculino , Doenças Metabólicas/metabolismo , Metaboloma/efeitos dos fármacos , Obesidade , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley
10.
Crit Rev Food Sci Nutr ; : 1-23, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33591236

RESUMO

Food nutrients plays a crucial role in human health, especially in gastrointestinal (GI) health. The effect of food nutrients on human health mainly depends on the digestion and fermentation process in the GI tract. In vitro GI digestion and fermentation models had the advantages of reproducibility, simplicity, universality, and could integrally simulate the in vivo conditions to mimic oral, gastric, small intestinal and large intestinal digestive processes. They could not only predict the relationship among material composition, structure and digestive characteristics, but also evaluate the bioavailability of material components and the impact of digestive metabolites on GI health. This review systematicly summarized the current state of the in vitro simulation models, and made detailed descriptions for their applications, advantages and disadvantages, and specially their applications in food carbohydrates. In addition, it also provided the suggestions for the improvement of in vitro models and firstly proposed to establish a set of standardized methods of in vitro dynamic digestion and fermentation conditions for food carbohydrates, which were in order to further evaluate more effects of the nutrients on human health in future.

11.
BMC Plant Biol ; 21(1): 21, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407149

RESUMO

BACKGROUND: DNA methylation is a conserved and important epigenetic modification involved in the regulation of numerous biological processes, including plant development, secondary metabolism, and response to stresses. However, no information is available regarding the identification of cytosine-5 DNA methyltransferase (C5-MTase) and DNA demethylase (dMTase) genes in the orchid Dendrobium officinale. RESULTS: In this study, we performed a genome-wide analysis of DoC5-MTase and DodMTase gene families in D. officinale. Integrated analysis of conserved motifs, gene structures and phylogenetic analysis showed that eight DoC5-MTases were divided into four subfamilies (DoCMT, DoDNMT, DoDRM, DoMET) while three DodMTases were divided into two subfamilies (DoDML3, DoROS1). Multiple cis-acting elements, especially stress-responsive and hormone-responsive ones, were found in the promoter region of DoC5-MTase and DodMTase genes. Furthermore, we investigated the expression profiles of DoC5-MTase and DodMTase in 10 different tissues, as well as their transcript abundance under abiotic stresses (cold and drought) and at the seedling stage, in protocorm-like bodies, shoots, and plantlets. Interestingly, most DoC5-MTases were downregulated whereas DodMTases were upregulated by cold stress. At the seedling stage, DoC5-MTase expression decreased as growth proceeded, but DodMTase expression increased. CONCLUSIONS: These results provide a basis for elucidating the role of DoC5-MTase and DodMTase in secondary metabolite production and responses to abiotic stresses in D. officinale.


Assuntos
Metilação de DNA/genética , DNA-Citosina Metilases/genética , Dendrobium/enzimologia , Dendrobium/genética , Oxirredutases/genética , Polissacarídeos/genética , Polissacarídeos/metabolismo , Arabidopsis/genética , DNA-Citosina Metilases/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Estudo de Associação Genômica Ampla , Oryza/genética , Oxirredutases/metabolismo
12.
Int J Biol Macromol ; 170: 636-651, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33385451

RESUMO

Glutaredoxins (GRXs) are disulfide oxidoreductases that are involved in various biological processes. However, little information on the role of GRXs in the regulation of fruit ripening and the response to stress is available. In this study, we isolated 64 GRX genes from banana genome. Their encoded GRX proteins could be classified into four classes: CC, CGFS, CPYC and GRL types. The distribution and synteny of these GRXs on chromosomes, the gene structures, the promoter sequences, and the possible protein subcellular localizations were characterized. Molecular interaction network analysis suggested that MaGRX might interact with glutathione reductase (GR), sulfiredoxin, peroxiredoxin (Prx), and NADPH-dependent thioredoxin reductase C (NTRC), contributing to the antioxidative defense of banana fruit. MicroRNA prediction showed that MaGRX genes might be targeted by different miRNAs. Transcriptome analysis characterized the expression profiles of different MaGRX genes during banana fruit ripening, and in response to different storage stresses. The results suggested that CC-type, CPYC-type and GRL-type MaGRXs might be more active than CGFS-type MaGRXs during banana fruit ripening and the response to stress. Moreover, MaGRX6/7/9/11/17/23/28 and MaGRL3/16/19 might play important roles in regulating fruit ripening or in response to low and high temperature, or Fusarium proliferatum infection.


Assuntos
Frutas/genética , Glutarredoxinas/genética , Musa/genética , Proteínas de Plantas/genética , Estresse Fisiológico/genética , Transcriptoma/genética , Cromossomos de Plantas/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Estudo de Associação Genômica Ampla/métodos , MicroRNAs/genética , Regiões Promotoras Genéticas/genética
13.
Anal Chem ; 93(3): 1515-1522, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33356146

RESUMO

Trans-interfacial behaviors of multiple ionic species at the interface between two immiscible electrolyte solutions (ITIES) are of importance to biomembrane mimicking, chemical and biosensing, and interfacial molecular catalysis. Utilizing host-guest interaction to facilitate ion transfer is an effective and commonly used method to decrease the Gibbs energy of transfer of a target molecule. Herein, we investigated a facilitated ion transfer (FIT) process of poly(amidoamine)dendrimer (PAMAM, G0-G2) by dibenzo-18-crown-6 (DB18C6) at the microinterfaces between water and 1,2-dichloroethane (µ-W/DCE). Because of the host-guest interaction between a dendrimer and a ligand, negative shifts of the transfer potentials were observed using cyclic voltammetry or Osteryoung square wave voltammetry. From the FIT behavior of the dendrimer, we revealed that each DB18C6 could selectively coordinate with one amino group. We first evaluated the protonated status of the intermediate state (1:2) exactly under the conditions the dendrimer (G1) transfers across the interface using the electrochemical mass spectrometry (EC-MS)-hyphenated technique, which is much smaller than the protonated status in the water phase (1:8 to 14). Using the same methodology, we also studied the facilitated transfer behaviors of G0 and G2. Based on these results, we put forward the mechanism of the FIT process, which might involve a deprotonating process at the interface for higher-generation dendrimers.

14.
Front Genet ; 11: 830, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193565

RESUMO

The great northern snakehead (Channa argus) is one of the most important economic and conservational fish in China. In this study, the melanocytes in the skin of two distinct color morphs C. argus were investigated and compared through employment of the microscopic analysis, hematoxylin and eosin (H&E) and Masson Fontana staining. Our results demonstrated the uneven distribution of melanocytes with extremely low density and most of them were in the state of aging or death. Meanwhile, there was no obvious pigment layer and melanocytes distribution pattern found in the albino-type (AT), while the melanocytes were evenly distributed with abundance in the bicolor-type (BT). The transcriptome analysis through Illumina HiSeq sequencing showed that a total of 34.93 Gb Clean Data was obtained, and Q30 base percentage reached 92.66%. The BT and AT northern snakeheads transcriptome data included a total of 56,039,701 and 60,410,063 clean reads (n = 3), respectively. In gene expression analyses, the sample correlation coefficients (r) were ranged between 0.92 and 1.00; the contribution of PC1 and PC2 were 50.25 and 13.73% by using PCA cluster analysis, the total number of DEGs were 1024 (559 up-regulated and 465 down-regulated), and the number of annotated DEGs was 767 (COG 172, KEGG 262, GO 288, SwissProt 548, Pfam 579 and NR 765). Additionally, 46,363 ± 873 and 44,947 ± 392 single nucleotide polymorphisms (SNPs) were compiled via genetic structure analysis, respectively. Ten key pigment-related genes were screened using qRT-PCR. And all of them revealed extremely higher expression levels in the skin of BT than those of AT. This is the first study to analyze the mechanism of albino characteristics of Channa via histology and transcriptomics, and also provide the oretical and practical support for the protection and development of germplasm resources for C. argus.

15.
PLoS One ; 15(10): e0240939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091041

RESUMO

The plasma seed treatment is effective for promoting seed germination in many crops. However, the biological mechanism remains unclear. Therefore, mRNA sequencing was used to screen differentially expressed genes in the germination process of Andrographis paniculata seeds treated with air plasma (power density = 8.99 J/cm3). Following plasma treatment, the germination percentages were significantly higher than those of the control, they were 3.5±0.6% vs. 0 at 28 hours after sowing (HAS) and 50.3±2.6% vs. 37.3±1.7% at 48 HAS. After unigenes were assembled and annotated, 125 differentially expressed genes (DEGs) were detected at 28 HAS, compared with nine DEGs at 48 HAS, but no DEGs were detected at 0 HAS, indicating that air plasma treatment mainly changed the gene expression of A. paniculata seeds at 28 HAS. The NCED5 expression level of the treated group was less than one-fifth of the control, and the expressions of three ethylene response factors were significantly higher than the control at 28 HAS, indicating that lower abscisic acid levels play an important role and ethylene signal transduction also participates in radicle protrusion. ACO, NRT1 and PRP3 expressions were significantly higher than in the control at 48 HAS, suggesting that higher ethylene levels cause the endosperm cap to weaken and start to grow root hairs and lateral roots earlier. These findings reveal that plasma promotes seed germination mainly by regulating the expression of hormone-related genes. And the possible signal transduction of related hormones was discussed.


Assuntos
Andrographis/genética , Germinação/genética , Sementes/genética , Transcriptoma/genética , Ácido Abscísico/metabolismo , Ar , Andrographis/metabolismo , Endosperma/genética , Etilenos/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Sementes/metabolismo
16.
Sci Prog ; 103(3): 36850420951056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32907490

RESUMO

Vertical screw conveyors are used widely in industry for elevating bulk materials over relatively short distances, but the problem of insufficient feeding and low conveying efficiency always exist in the vertical conveying process. In this paper, a vertical screw conveyor with variable screw section is presented, and the characteristics of vertical screw conveyor are investigated under the variable screw sections using discrete element method (DEM). The results show that the particle volume fraction in the inlet and the mass flow rate increase in the condition of variable screw section, and the screw rotational speed has a significant influence on mass flow rate. It is evident that the design of variable screw section provides an effective way in improving the particle feeding rate and the conveying efficiency.

17.
BMC Plant Biol ; 20(1): 406, 2020 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-32878602

RESUMO

BACKGROUND: Oat (Avena sativa L.) is a recognized health-food, and the contributions of its different candidate A-genome progenitor species remain inconclusive. Here, we report chloroplast genome sequences of eleven Avena species, to examine the plastome evolutionary dynamics and analyze phylogenetic relationships between oat and its congeneric wild related species. RESULTS: The chloroplast genomes of eleven Avena species (size range of 135,889-135,998 bp) share quadripartite structure, comprising of a large single copy (LSC; 80,014-80,132 bp), a small single copy (SSC; 12,575-12,679 bp) and a pair of inverted repeats (IRs; 21,603-21,614 bp). The plastomes contain 131 genes including 84 protein-coding genes, eight ribosomal RNAs and 39 transfer RNAs. The nucleotide sequence diversities (Pi values) range from 0.0036 (rps19) to 0.0093 (rpl32) for ten most polymorphic genes and from 0.0084 (psbH-petB) to 0.0240 (petG-trnW-CCA) for ten most polymorphic intergenic regions. Gene selective pressure analysis shows that all protein-coding genes have been under purifying selection. The adjacent position relationships between tandem repeats, insertions/deletions and single nucleotide polymorphisms support the evolutionary importance of tandem repeats in causing plastome mutations in Avena. Phylogenomic analyses, based on the complete plastome sequences and the LSC intermolecular recombination sequences, support the monophyly of Avena with two clades in the genus. CONCLUSIONS: Diversification of Avena plastomes is explained by the presence of highly diverse genes and intergenic regions, LSC intermolecular recombination, and the co-occurrence of tandem repeat and indels or single nucleotide polymorphisms. The study demonstrates that the A-genome diploid-polyploid lineage maintains two subclades derived from different maternal ancestors, with A. longiglumis as the first diverging species in clade I. These genome resources will be helpful in elucidating the chloroplast genome structure, understanding the evolutionary dynamics at genus Avena and family Poaceae levels, and are potentially useful to exploit plastome variation in making hybrids for plant breeding.


Assuntos
Avena/genética , Evolução Molecular , Genoma de Cloroplastos/genética , Genoma de Planta/genética , Filogenia , Polimorfismo Genético
18.
BMC Genomics ; 21(1): 524, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727352

RESUMO

BACKGROUNDS: Paphiopedilum is an important genus of the orchid family Orchidaceae and has high horticultural value. The wild populations are under threat of extinction because of overcollection and habitat destruction. Mature seeds of most Paphiopedilum species are difficult to germinate, which severely restricts their germplasm conservation and commercial production. The factors inhibiting germination are largely unknown. RESULTS: In this study, large amounts of non-methylated lignin accumulated during seed maturation of Paphiopedilum armeniacum (P. armeniacum), which negatively correlates with the germination rate. The transcriptome profiles of P. armeniacum seed at different development stages were compared to explore the molecular clues for non-methylated lignin synthesis. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that a large number of genes associated with phenylpropanoid biosynthesis and phenylalanine metabolism during seed maturation were differentially expressed. Several key genes in the lignin biosynthetic pathway displayed different expression patterns during the lignification process. PAL, 4CL, HCT, and CSE upregulation was associated with C and H lignin accumulation. The expression of CCoAOMT, F5H, and COMT were maintained at a low level or down-regulated to inhibit the conversion to the typical G and S lignin. Quantitative real-time RT-PCR analysis confirmed the altered expression levels of these genes in seeds and vegetative tissues. CONCLUSIONS: This work demonstrated the plasticity of natural lignin polymer assembly in seed and provided a better understanding of the molecular mechanism of seed-specific lignification process.


Assuntos
Lignina , Orchidaceae , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Germinação/genética , Lignina/metabolismo , Orchidaceae/metabolismo , Sementes/genética , Sementes/metabolismo , Transcriptoma
19.
J Environ Manage ; 269: 110854, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32561025

RESUMO

Coal dust diffusion during coal transportation and storage causes serious environmental pollution. The existing dust suppressant in previous studies was unable to achieve the expected effects owing to severe wind damage and rain erosion. Therefore, the current study synthesized and prepared an efficient and applicable dust suppressant for coal transportation and storage. Infrared spectroscopy and scanning electron microscope experiments were conducted during the synthesis to analyze the microstructure changes in the synthetic products. Moreover, viscosity was used as the evaluation index in the single-factor experiments to obtain the optimal synthesis conditions. Performance measurement results showed that the prepared dust suppressant had a strong protective effect on coal powder and could effectively resist the impact of wind damage and rain erosion. Compared with other dust suppressants, the proposed dust suppressant prepared showed more evident positive effects and longer lasting action time in the quantitative test. Moreover, the dried product could synergistically combust with coal powder, thereby possibly mitigating the tedious post-treatment process and increasing the utilization rate of resources.


Assuntos
Minas de Carvão , Carvão Mineral , Poeira , Monitoramento Ambiental , Poluição Ambiental , Vento
20.
Acad Radiol ; 27(5): 603-608, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32204987

RESUMO

Coronavirus disease is an emerging infection caused by a novel coronavirus that is moving rapidly. High resolution computed tomography (CT) allows objective evaluation of the lung lesions, thus enabling us to better understand the pathogenesis of the disease. With serial CT examinations, the occurrence, development, and prognosis of the disease can be better understood. The imaging can be sorted into four phases: early phase, progressive phase, severe phase, and dissipative phase. The CT appearance of each phase and temporal progression of the imaging findings are demonstrated.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Inteligência Artificial , COVID-19 , Infecções por Coronavirus/diagnóstico , Progressão da Doença , Diagnóstico Precoce , Humanos , Pulmão/patologia , Pandemias , Isolamento de Pacientes , Pneumonia Viral/diagnóstico
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