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1.
Int J Mol Sci ; 25(12)2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38928338

RESUMO

The flavonoids in citrus fruits are crucial physiological regulators and natural bioactive products of high pharmaceutical value. Melatonin is a pleiotropic hormone that can regulate plant morphogenesis and stress resistance and alter the accumulation of flavonoids in these processes. However, the direct effect of melatonin on citrus flavonoids remains unclear. In this study, nontargeted metabolomics and transcriptomics were utilized to reveal how exogenous melatonin affects flavonoid biosynthesis in "Bingtangcheng" citrus fruits. The melatonin treatment at 0.1 mmol L-1 significantly increased the contents of seven polymethoxylated flavones (PMFs) and up-regulated a series of flavonoid pathway genes, including 4CL (4-coumaroyl CoA ligase), FNS (flavone synthase), and FHs (flavonoid hydroxylases). Meanwhile, CHS (chalcone synthase) was down-regulated, causing a decrease in the content of most flavonoid glycosides. Pearson correlation analysis obtained 21 transcription factors co-expressed with differentially accumulated flavonoids, among which the AP2/EREBP members were the most numerous. Additionally, circadian rhythm and photosynthesis pathways were enriched in the DEG (differentially expressed gene) analysis, suggesting that melatonin might also mediate changes in the flavonoid biosynthesis pathway by affecting the fruit's circadian rhythm. These results provide valuable information for further exploration of the molecular mechanisms through which melatonin regulates citrus fruit metabolism.


Assuntos
Citrus , Flavonoides , Frutas , Regulação da Expressão Gênica de Plantas , Melatonina , Metabolômica , Citrus/metabolismo , Citrus/efeitos dos fármacos , Citrus/genética , Melatonina/farmacologia , Melatonina/metabolismo , Flavonoides/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Frutas/metabolismo , Frutas/efeitos dos fármacos , Frutas/genética , Metabolômica/métodos , Perfilação da Expressão Gênica , Transcriptoma , Metaboloma/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética
2.
J Integr Plant Biol ; 66(2): 285-299, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38314502

RESUMO

Roots are fundamental for plants to adapt to variable environmental conditions. The development of a robust root system is orchestrated by numerous genetic determinants and, among them, the MADS-box gene ANR1 has garnered substantial attention. Prior research has demonstrated that, in chrysanthemum, CmANR1 positively regulates root system development. Nevertheless, the upstream regulators involved in the CmANR1-mediated regulation of root development remain unidentified. In this study, we successfully identified bric-a-brac, tramtrack and broad (BTB) and transcription adapter putative zinc finger (TAZ) domain protein CmBT1 as the interacting partner of CmANR1 through a yeast-two-hybrid (Y2H) screening library. Furthermore, we validated this physical interaction through bimolecular fluorescence complementation and pull-down assays. Functional assays revealed that CmBT1 exerted a negative influence on root development in chrysanthemum. In both in vitro and in vivo assays, it was evident that CmBT1 mediated the ubiquitination of CmANR1 through the ubiquitin/26S proteasome pathway. This ubiquitination subsequently led to the degradation of the CmANR1 protein and a reduction in the transcription of CmANR1-targeted gene CmPIN2, which was crucial for root development in chrysanthemum. Genetic analysis suggested that CmBT1 modulated root development, at least in part, by regulating the level of CmANR1 protein. Collectively, these findings shed new light on the regulatory role of CmBT1 in degrading CmANR1 through ubiquitination, thereby repressing the expression of its targeted gene and inhibiting root development in chrysanthemum.


Assuntos
Chrysanthemum , Chrysanthemum/genética , Chrysanthemum/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitinação , Ligação Proteica , Dedos de Zinco , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
3.
Int Wound J ; 21(1): e14403, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37735819

RESUMO

This analysis systematically reviewed the efficacy of evidence-based care on diabetic foot ulcers. A computerised literature search was conducted for randomised controlled studies (RCTs) of evidence-based care interventions for the treatment of diabetic foot ulcers using the PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), China Biomedical Literature Database (CBM) and Wanfang databases from the date of inception of each database to June 2023. The articles were independently screened, data were extracted by two researchers, and the quality of each study was assessed using the Cochrane bias assessment tool. Meta-analysis of the data was performed using RevMan 5.4 software. Twenty-five RCTs with a total of 2272 patients were included. Meta-analysis showed that, compared with other care methods, evidence-based care significantly improved the treatment efficacy of diabetic foot ulcers (odds ratio: 3.91, 95% confidence interval [CI]: 2.76 to 5.53, p < 0.001) and significantly reduced their fasting plasma glucose (mean difference [MD]: -1.10, 95% CI: -1.24 to -0.96, p < 0.001), 2-h postprandial glucose (2hPG) (MD: -1.69, 95% CI: -2.07 to -1.31, p < 0.001) and glycated haemoglobin (HbA1c) (MD: -0.71, 95% CI: -0.94 to -0.48, p < 0.001). Evidence-based care intervention is effective at reducing FPG, 2hPG and HbA1c levels and improving treatment efficacy in patients with diabetic foot ulcers.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/terapia , Medicina Baseada em Evidências , Hemoglobinas Glicadas , Resultado do Tratamento , China
4.
Small ; 19(16): e2206824, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683213

RESUMO

Nanoionic technologies are identified as a promising approach to modulating the physical properties of solid-state dielectrics, which have resulted in various emergent nanodevices, such as nanoionic resistive switching devices and magnetoionic devices for memory and computing applications. Previous studies are limited to single-type ion manipulation, and the investigation of multiple-type ion modulation on the coupled magnetoelectric effects, for developing information devices with multiple integrated functionalities, remains elusive. Here, a dual-ion solid-state magnetoelectric heterojunction based on Pt/HfO2- x /NiOy /Ni with reconfigurable magnetoresistance (MR) characteristics is reported for in-memory encryption. It is shown that the oxygen anions and nickel cations can be selectively driven by voltages with controlled polarity and intensity, which concurrently change the overall electrical resistance and the interfacial magnetic coupling, thus significantly modulate the MR symmetry. Based on this device, a magnetoelectric memory prototype array with in-memory encryption functionality is designed for the secure storage of image and digit information. Along with the advantages including simple structure, multistate encryption, good reversibility, and nonvolatile modulation capability, this proof-of-concept device opens new avenues toward next-generation compact electronics with integrated information functionalities.

5.
Sci Technol Adv Mater ; 24(1): 2162325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36684849

RESUMO

With the rapid development of intelligent robotics, the Internet of Things, and smart sensor technologies, great enthusiasm has been devoted to developing next-generation intelligent systems for the emulation of advanced perception functions of humans. Neuromorphic devices, capable of emulating the learning, memory, analysis, and recognition functions of biological neural systems, offer solutions to intelligently process sensory information. As one of the most important neuromorphic devices, Electrolyte-gated transistors (EGTs) have shown great promise in implementing various vital neural functions and good compatibility with sensors. This review introduces the materials, operating principle, and performances of EGTs, followed by discussing the recent progress of EGTs for synapse and neuron emulation. Integrating EGTs with sensors that faithfully emulate diverse perception functions of humans such as tactile and visual perception is discussed. The challenges of EGTs for further development are given.

6.
Crit Rev Food Sci Nutr ; 62(14): 3817-3832, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33406881

RESUMO

Hydrogels, polymeric network materials, are capable of swelling and holding the bulk of water in their three-dimensional structures upon swelling. In recent years, hydrogels have witnessed increased attention in food and biomedical applications. In this paper, the available literature related to the design concepts, types, functionalities, and applications of hydrogels with special emphasis on food applications was reviewed. Hydrogels from natural polymers are preferred over synthetic hydrogels. They are predominantly used in diverse food applications for example in encapsulation, drug delivery, packaging, and more recently for the fabrication of structured foods. Natural polymeric hydrogels offer immense benefits due to their extraordinary biocompatible nature. Hydrogels based on natural/edible polymers, for example, those from polysaccharides and proteins, can serve as prospective alternatives to synthetic polymer-based hydrogels. The utilization of hydrogels has so far been limited, despite their prospects to address various issues in the food industries. More research is needed to develop biomimetic hydrogels, which can imitate the biological characteristics in addition to the physicochemical properties of natural materials for different food applications.


Assuntos
Hidrogéis , Polímeros , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Polímeros/química , Polissacarídeos/química , Estudos Prospectivos
7.
Physiol Plant ; 174(1): e13596, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34761393

RESUMO

Sugars are essential regulatory molecules involved in plant growth and development and defense response. Although the relationship between sugars and disease resistance has been widely discussed, the underlying molecular mechanisms remain unexplored. Ring rot caused by Botryosphaeria dothidea (B. dothidea), which severely affects fruit quality and yield, is a destructive disease of apples (Malus domestica Borkh.). The present study found that the degree of disease resistance in apple fruit was closely related to glucose content. Therefore, the gene encoding a hexokinase, MdHXK1, was isolated from the apple cultivar 'Gala', and characterized during the defense response. Overexpression of MdHXK1 enhanced disease resistance in apple calli, leaves and fruits by increasing the expression levels of genes related to salicylate (SA) synthesis (PHYTOALEXIN DEFICIENT 4, PAD4; PHENYLALANINE AMMONIA-LYASE, PAL; and ENHANCED DISEASE SUSCEPTIBILITY 1, EDS1) and signaling (PR1; PR5; and NONEXPRESSER OF PR GENES 1, NPR1) as well as increasing the superoxide (O2- ) production rate and the hydrogen peroxide (H2 O2 ) content. Overall, the study provides new insights into the MdHXK1-mediated molecular mechanisms by which glucose signaling regulates apple ring rot resistance.


Assuntos
Ascomicetos , Malus , Ascomicetos/fisiologia , Resistência à Doença/genética , Glucose/metabolismo , Malus/genética , Malus/metabolismo , Doenças das Plantas/genética
8.
J Integr Plant Biol ; 64(4): 884-900, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35199464

RESUMO

Sugars are involved in plant growth, fruit quality, and signaling perception. Therefore, understanding the mechanisms involved in soluble sugar accumulation is essential to understand fruit development. Here, we report that MdPFPß, a pyrophosphate-dependent phosphofructokinase gene, regulates soluble sugar accumulation by enhancing the photosynthetic performance and sugar-metabolizing enzyme activities in apple (Malus domestica Borkh.). Biochemical analysis revealed that a basic helix-loop-helix (bHLH) transcription factor, MdbHLH3, binds to the MdPFPß promoter and activates its expression, thus promoting soluble sugar accumulation in apple fruit. In addition, MdPFPß overexpression in tomato influenced photosynthesis and carbon metabolism in the plant. Furthermore, we determined that MdbHLH3 increases photosynthetic rates and soluble sugar accumulation in apple by activating MdPFPß expression. Our results thus shed light on the mechanism of soluble sugar accumulation in apple leaves and fruit: MdbHLH3 regulates soluble sugar accumulation by activating MdPFPß gene expression and coordinating carbohydrate allocation.


Assuntos
Malus , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carboidratos , Frutas/genética , Frutas/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Malus/genética , Malus/metabolismo , Fosfofrutoquinases/genética , Fosfofrutoquinases/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Açúcares/metabolismo
9.
BMC Plant Biol ; 21(1): 79, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33549046

RESUMO

BACKGROUND: MADS-box transcription factors (TFs) are the key regulators of multiple developmental processes in plants; among them, a chrysanthemum MADS-box TF CmANR1 has been isolated and described as functioning in root development in response to high nitrate concentration signals. However, how CmANR1 affects root and shoot development remains unclear. RESULTS: We report that CmANR1 plays a positive role in root system development in chrysanthemum throughout the developmental stages of in vitro tissue cultures. Metabolomics combined with transcriptomics assays show that CmANR1 promotes robust root system development by facilitating nitrate assimilation, and influencing the metabolic pathways of amino acid, glycolysis, and the tricarboxylic acid cycle (TCA) cycle. Also, we found that the expression levels of TFs associated with the nitrate signaling pathways, such as AGL8, AGL21, and LBD29, are significantly up-regulated in CmANR1-transgenic plants relative to the wild-type (WT) control; by contrast, the expression levels of RHD3-LIKE, LBD37, and GATA23 were significantly down-regulated. These results suggest that these nitrate signaling associated TFs are involved in CmANR1-modulated control of root development. In addition, CmANR1 also acts as a positive regulator to control shoot growth and development. CONCLUSIONS: These findings provide potential mechanisms of MADS-box TF CmANR1 modulation of root and shoot development, which occurs by regulating a series of nitrate signaling associated TFs, and influencing the metabolic pathways of amino acid and glycolysis, as well as TCA cycle and nitrate assimilation.


Assuntos
Chrysanthemum/genética , Genes de Plantas , Proteínas de Domínio MADS/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/genética , Chrysanthemum/crescimento & desenvolvimento , Ciclo do Ácido Cítrico , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Glicólise , Proteínas de Domínio MADS/metabolismo , Metabolômica , Modelos Biológicos , Nitratos/metabolismo , Fotossíntese , Análise de Componente Principal , Transdução de Sinais , Transcriptoma/genética
10.
Plant Biotechnol J ; 19(2): 285-299, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32757335

RESUMO

Changes in carbohydrates and organic acids largely determine the palatability of edible tissues of horticulture crops. Elucidating the potential molecular mechanisms involved in the change in carbohydrates and organic acids, and their temporal and spatial crosstalk are key steps in understanding fruit developmental processes. Here, we used apple (Malus domestica Borkh.) as research materials and found that MdbHLH3, a basic helix-loop-helix transcription factor (bHLH TF), modulates the accumulation of malate and carbohydrates. Biochemical analyses demonstrated that MdbHLH3 directly binds to the promoter of MdcyMDH that encodes an apple cytosolic NAD-dependent malate dehydrogenase, activating its transcriptional expression, thereby promoting malate accumulation in apple fruits. Additionally, MdbHLH3 overexpression increased the photosynthetic capacity and carbohydrate levels in apple leaves and also enhanced the carbohydrate accumulation in fruits by adjusting carbohydrate allocation from sources to sinks. Overall, our findings provide new insights into the mechanism of how the bHLH TF MdbHLH3 modulates the fruit quality. It directly regulates the expression of cytosolic malate dehydrogenase MdcyMDH to coordinate carbohydrate allocation and malate accumulation in apple.


Assuntos
Malus , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Frutose , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Malatos , Malus/genética , Malus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
11.
Exp Mol Pathol ; : 104653, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34043982

RESUMO

OBJECTIVE: To investigate the mechanism of HSPB8 (heat shock protein beta-8) in the growth and metastatic properties of glioma cells. METHODS: HSPB8 expression in glioma tissue and cell was detected via Western blotting. Then, glioma U87 and U251 cell lines were divided into Mock group, Control siRNA group, HSPB8 siRNA-1 group and HSPB8 siRNA-2 group. Cell proliferation was detected using MTT assay, while its invasion, migration and apoptosis were determined by Transwell, wound-healing and flow cytometry, respectively. The expression of HSPB8 and ERK-CREB pathway-related molecules were also measured by Western blotting. Xenograft models were constructed on nude mice, and accordingly, the growth curve of subcutaneous xenograft was prepared. RESULTS: In glioma tissues, HSPB8 expression was upregulated with the increasing grade of glioma. Besides, glioma cells in the HSPB8 siRNA-1 group and HSPB8 siRNA-2 group manifested the significant enhancement in apoptotic rates and reductions in its proliferation, migration and invasion compared to those in the Mock group, meanwhile, the expression of HSPB8, p-ERK1/2/ERK1/2 and p-CREB/CREB were downregulated. On the other hand, the tumor growth in the nude mice of Ad-HSPB8 shRNA-1 group and Ad-HSPB8 shRNA-2 group was retarded significantly, with an acute decrease in the tumor weight. CONCLUSION: Silencing HSPB8 can inhibit the malignant features, while facilitate the apoptosis of glioma cells, with inactivation of ERK-CREB pathway.

12.
Bioorg Chem ; 107: 104578, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33383323

RESUMO

Hyperelodione D (1), an undescribed polyprenylated phloroglucinol derivative possessing 6/6/5/5 fused tetracyclic core, together with hyperelodiones E-F (2-3), two unreported analogues bearing 6/5/5 fused tricyclic structure, were isolated from Hypericum elodeoides Choisy. Their planar structures were elucidated by spectroscopic analysis (HRESIMS, 1D and 2D NMR) and their absolute configurations were determined by comparison of experimental and calculated ECD data. The cytotoxicity and retinoid X receptor-α (RXRα) related activities of the isolates were evaluated and the plausible biogenetic pathways of 1-3 were proposed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Hypericum/química , Floroglucinol/farmacologia , Receptor X Retinoide alfa/antagonistas & inibidores , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Floroglucinol/química , Floroglucinol/isolamento & purificação , Receptor X Retinoide alfa/metabolismo , Relação Estrutura-Atividade
13.
J Ultrasound Med ; 40(9): 1851-1861, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33216384

RESUMO

OBJECTIVE: To explore the clinical value of real-time shear wave ultrasonic elastography in diagnosing the depth of infiltrating muscularis of endometrial cancer. METHODS: Seventy-one patients with stage I endometrial cancer infiltrating the myometrium and 37 patients with normal physical examination were enrolled and divided into three groups: endometrial cancer superficial muscle infiltration group, endometrial cancer deep muscle infiltration group, and normal control group. After completing 2-dimensional ultrasound examination, each patient switched to the real-time shear wave elastography mode to measure the elasticity values Emax, Emean, and Esd. RESULTS: For control group, comparison of elastic modulus values between superficial muscular layer near the intimal surface and the deep muscular layer near the serosa surface showed no difference (P > 0.05). For endometrial cancer superficial muscular infiltration group, significant difference was found regarding the elastic modulus values of infiltrated muscular layer and uninfiltrated muscular layer (Emax and Emean) without difference for Esd (P > 0.05). A significant difference of elastic modulus was observed between control group and deep myometrial infiltration group (P < 0.05) without difference of Emean or Emax but with difference of Esd. The accuracy in diagnosing muscular layer infiltration was 78.9% for Emax cutoff and 82.5% for Emean cutoff. The rate of using Emax ≥32.22 kPa or Emean ≥27.54 kPa as the ultrasound standard for diagnosing myometrium infiltration was 92.9%. The accuracy for the diagnosis of muscular layer infiltration was 96.1% for Emax cutoff, 94.1% for Emean cutoff and 86.3% for Esd cutoff. CONCLUSION: Real-time shear wave elastography is helpful to determine the depth of infiltrating myometrium of endometrial cancer.


Assuntos
Técnicas de Imagem por Elasticidade , Neoplasias do Endométrio , Diagnóstico Diferencial , Módulo de Elasticidade , Neoplasias do Endométrio/diagnóstico por imagem , Feminino , Humanos , Miométrio/diagnóstico por imagem
14.
Ecotoxicology ; 30(4): 622-631, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33830384

RESUMO

The pressure-state-response (PSR) model was applied to establish a mangrove ecosystem health evaluation system combined with analytical hierarchy process (AHP) in this paper. The mangrove wetlands are divided into five ecological levels: excellent health, good health, health, sub-health and morbidity, which is based on the comprehensive health index (CHI) value. Twelve representative sites were selected for sampling to assess the ecological health condition of mangroves. As a result, the ecological health level of Gaoqiao mangrove area is excellent health; the ecological health level of Taiping mangrove area is good health; the ecological health level of Huguang and Qi'ao mangrove area is health; the ecological health level of Techeng and He'an mangrove area is sub-health; the ecological health level of Huidong mangrove area is morbidity. These results will give some advises for ecological protection and biological resource sustainable development of mangrove ecosystem in China.


Assuntos
Ecossistema , Áreas Alagadas , China
15.
Ecotoxicology ; 30(9): 1826-1840, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34618290

RESUMO

Cold events had broadly affected the survival and geographic distribution of mangrove plants. Kandelia obovata, has an excellent cold tolerance as a true halophyte and widespread mangrove species. In this study, physiological characters and comparative proteomics of leaves of K. obovata were performed under cold treatment. The physiological analysis showed that K. obovata could alleviate its cold-stress injuries through increasing the levels of antioxidants, the activities of related enzymes, as well as osmotic regulation substances (proline). It was detected 184 differentially expressed protein spots, and of 129 (70.11%) spots were identified. These proteins have been involved in several pathways such as the stress and defense, photosynthesis and photorespiration, signal transduction, transcription factors, protein biosynthesis and degradation, molecular chaperones, ATP synthesis, the tricarboxylic acid (TCA) cycle and primary metabolisms. The protein post-translational modification may be a common phenomenon and plays a key role in cold-response process in K. obovata. According to our precious work, a schematic diagram was drawn for the resistance or adaptation strategy of mangrove plants under cold stress. This study provided valuable information to understand the mechanism of cold tolerance of K. obovata.


Assuntos
Rhizophoraceae , Resposta ao Choque Frio , Fotossíntese , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteômica , Rhizophoraceae/metabolismo , Estresse Fisiológico
16.
Ecotoxicology ; 30(9): 1808-1815, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34269924

RESUMO

In this study, Illumina MiSeq sequencing of the 16 S rRNA gene was used to describe the bacterial communities in the South China Sea (SCS) during the southwest monsoon period. We targeted different regions in the SCS and showed that bacterial community was driven by the effects of the river, upwelling, and mesoscale eddy through changing the environmental factors (salinity, temperature, and nutrients). Distinct bacterial communities were observed among different chemical conditions, especially between the estuary and the open sea. The abundance of Burkholderiales, Frankiales, Flavobacteriales, and Rhodobacterales dominated the estuary and its adjacent waters. Bacteria in cyclonic eddy were dominated by Methylophilales and Pseudomonadales, whereas Prochlorococcus, SAR11 clade, and Oceanospirillales had relatively high abundance in the anticyclonic eddy. Overall, the abundance of specific phylotypes significantly varied among samples with different chemical conditions. Chemical conditions probably act as a driver that shapes and controls the diversity of bacteria in the SCS. This study suggests that the interaction between microbial and environmental conditions needs to be further considered to fully understand the diversity and function of marine microbes.


Assuntos
Bactérias , Água do Mar , Bactérias/genética , China , Estuários , Oceanos e Mares , Filogenia , Rios
17.
J Sci Food Agric ; 101(9): 3862-3869, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33336364

RESUMO

BACKGROUND: Dihydromyricetin (DMY) is a natural dihydroflavonol with many bioactive effects. However, the physicochemical properties of DMY related to its bioavailability, especially its stability, are unclear. RESULTS: The effects of pH, temperature, metal ions and ascorbic acid (AA) on the stability of DMY were studied using high-performance liquid chromatography (HPLC). The bioavailability of DMY in the presence and absence of AA was compared. Dihydromyricetin was unstable in weak alkaline solutions, and the degradation was significantly accelerated in the presence of Cu2+ and Fe3+ . The degradation process followed the first-order kinetic model. The degradation rate constant (k) increased with increasing pH and temperature. The remaining DMY was only 49% of its initial concnentration after 4 h in simulated intestinal fluid (SIF) at 37 °C. However, by supplementing with AA, the degradation of DMY was rarely occured within 6 h. The solubility of DMY at pH 3-5 was about 750 µg mL-1 , slightly increasing to 853 µg mL-1 at pH 6. Pharmacokinetic studies showed that the bioavailability of DMY increased from 0.122% to 0.341% by supplementing with AA (10% of DMY). CONCLUSION: The degradation of DMY is one reason for its poor bioavailability. The presence of AA could significantly improve the stability of DMY, and further improve its bioavailability in rats. © 2020 Society of Chemical Industry.


Assuntos
Ácido Ascórbico/química , Flavonóis/química , Flavonóis/farmacocinética , Animais , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estabilidade de Medicamentos , Feminino , Flavonóis/administração & dosagem , Cinética , Ratos , Ratos Sprague-Dawley , Solubilidade
18.
Ecotoxicology ; 29(6): 718-725, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32394360

RESUMO

Kandelia obovata is one of the cold tolerant mangrove plants along the China coast. To reveal the cold tolerant mechanism of K. obovata, the present work isolated two CBF/DREB1 genes (designated KoCBF1 and KoCBF3) from cold-stressed K. obovata and characterized their expression profiles in various organs and in response to multiple abiotic stresses. The deduced proteins of KoCBF1 and 3 all contain specific features of CBFs, and show high similarity to AmCBF1 and 3 from Avicennia marina, respectively. Different expression patterns of the two CBF orthologous under various abiotic stresses and exogenous hormone suggested that they may have different regulators and be involved in different regulatory pathway. The high basal and cold induced expression of the two genes indicated that they may all play important roles in growth and cold resistance of plants. The significant induction of KoCBF3 after salt and lead (Pb2+) treatments suggested that this CBF gene may also participate in response to salinity and heavy metal stresses. This study will provide a better understanding of CBF-regulated stress-resistant mechanism, which may be benefit in mangrove biotechnological breeding, high-latitude transplanting, and bioremediation of heavy metal pollutions.


Assuntos
Rhizophoraceae/fisiologia , Estresse Fisiológico/genética , Avicennia , China , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Rhizophoraceae/genética , Salinidade
19.
Ecotoxicology ; 29(6): 726-735, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32337665

RESUMO

The present work isolated a CBF/DREB1 gene from mangrove Bruguiera gymnorrhiza (BgCBF1) and compared its expression levels in various tissues under normal condition and cold stress, and in leaves exposed to various environmental stimuli. Results showed that the BgCBF1 deduced protein showed almost 100% similarities to that of AcCBF1 from Aegiceras corniculatum and AmCBF1 from Avicennia marina. Real-time quantitative PCR analysis showed that BgCBF1 gene displayed constitute expression in leaf, stem and root samples of plantlets under normal condition, but with different expression levels and tissue preference. When exposed to cold, BgCBF1 could be rapidly, slightly and transiently induced in all tissues. Furthermore, the BgCBF1 gene in leaves displayed a transient and small induction after salt and drought (PEG) exposure, while exhibited relatively high up-regulated expression after the phytohormone abscisic acid (ABA) treatment. These results suggest that the BgCBF1 gene may participate in the ABA mediated development and protection of plant against cold and drought. Further studies on its promoters and downstream genes will be needed to better understand its functions.


Assuntos
Proteínas de Plantas/genética , Rhizophoraceae/genética , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Áreas Alagadas
20.
Ecotoxicology ; 29(6): 684-690, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32394359

RESUMO

Tidal flooding can directly result in oxygen (O2) shortage, however the functions of root aeration in flooding tolerance and O2 dynamics within mangroves are still poorly understood. Thus, in this study, the correlations among waterlogging tolerance, root porosity and O2 movement within the plants were investigated using two mangrove species (Aegiceras corniculatum and Bruguiera gymnorrhiza) and a semi-mangrove Heritiera littoralis. Based on the present data, the species A. corniculatum and B. gymnorrhiza, which possessed higher root porosity, exhibited higher waterlogging tolerance, while H. littoralis is intolerant. Increased root porosity, leaf stoma, and total ROL were observed in the roots of A. corniculatum and B. gymnorrhiza growing in stagnant solution when compared to respective aerated controls. As for ROL spatial pattern along roots, external anaerobic condition could promote ROL from apical root regions but reduce ROL from basal roots, leading to a 'tighter barrier'. In summary, the present study indicated that the plants (e.g., A. corniculatum and B. gymnorrhiza) prioritized to ensure O2 diffusion towards root tips under waterlogging by increasing aerenchyma formation and reducing O2 leakage at basal root regions.


Assuntos
Primulaceae , Rhizophoraceae , Áreas Alagadas , Eutrofização , Oxigênio/metabolismo , Raízes de Plantas/fisiologia
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