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1.
Food Chem ; 444: 138532, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38330600

RESUMO

Chemical vapor generation (CVG) was used as a gaseous sample introduction technique for the visual/smartphone RGB readout colorimetric system, with the advantages of efficient matrix elimination and high vapor generation efficiency, this analytical system exhibits a good selectivity and sensitivity. Sulfide ion (S2-) in solution was transformed to its volatile form (H2S), the generated H2S reacted with a silver-containing metal organic framework (Ag-BTC) selectively, Ag2S was thus generated. Ag-BTC (fabricated on paper sheet) changed from white to dark brown, the color variance was identified by smartphone and naked-eye simultaneously. Under the optimized conditions, a limit of detection of 0.02 µg/mL was obtained by naked-eye. Several water samples and commercial food additives were analyzed for confirming its accuracy and potential application for on-site detection, recoveries ranging 94-110 % were obtained. To meet the demand of on-site analysis of S2-, this colorimetric system was integrated in a portable/miniaturized analytical kit. It is an easy-used, affordable and portable analytical kit for S2- detection in field.


Assuntos
Colorimetria , Smartphone , Limite de Detecção , Colorimetria/métodos , Água , Gases , Sulfetos
2.
Food Chem ; 428: 136806, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37450952

RESUMO

The reaction mechanism of Ag-containing metal organic framework (Ag-BTC) and hydrogen arsenide (AsH3) was discussed in detail in this work. Silver ions in Ag-BTC were reacted with AsH3, and silver nanoparticles were generated on the surface of Ag-BTC, causing its color changed. This property was further applied to a hydride generation-colorimetric analytical system. As(III) was converted to AsH3via hydride generation and then reacted with the Ag-BTC (immobilized on test paper), leading to the test paper changed from white to black. Visual colorimetric and smartphone RGB readout mode were used for this analytical system. The results could be readout by naked-eye in visual colorimetric mode and a smartphone in RGB readout mode. Under the optimized conditions, As(III) concentration as low as 10 µg/L and 50 µg/L could be readout by smartphone and naked-eye, respectively. This method was further successful applied to As(III) determination in real samples (drinking water samples and scented tea samples), with recoveries of 91-113%.


Assuntos
Arsênio , Nanopartículas Metálicas , Estruturas Metalorgânicas , Colorimetria/métodos , Smartphone , Prata
3.
Food Chem ; 427: 136648, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37399644

RESUMO

It is necessary to efficient detection hydrazine in food. Exploring highly sensitive, low-cost and fast response electrochemical hydrazine sensing methods has been a challenge in this field. In this paper, a conformal transformation method is used to prepare rose flower-like NiCo-LDH derivating from the bimetallic NiCo-MOFs, and the N2H4 sensing platform with a large electrocatalytic area, high conductivity and good stability was constructed. Based on the synergy between Ni and Co and the remarkable catalytic activity of the rough 3D flower-like structure, the N2H4 sensor has a linear response in the concentration range of 0.001-1 mmol/L and 1-7 mmol/L, with a sensitivity of 5342 µA L mmol-1 cm-2 and 2965 µA L mmol-1 cm-2 (S/N = 3), respectively, and low limit of detection of 0.043 µmol/L. This study opens a new door for the successful application of electrochemical sensors to detect N2H4 in real food samples.


Assuntos
Técnicas Eletroquímicas , Flores , Análise por Conglomerados , Condutividade Elétrica , Eletrodos
4.
Food Chem X ; 18: 100634, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-36968312

RESUMO

A miniaturized/portable dual-mode colorimetric analytical system was established for inorganic arsenic determination in honey and drinking water samples. Hydride generation (HG) was utilized as a sampling technique for this colorimetric system, because of its high generation efficiency and efficient matrix separation. AsH3 was generated via HG and then reacted with HAuCl4, gold nanoparticles (Au NPs) were formed on the paper sheet, leading the paper color changed from light yellow to dark blue, it could be readout by naked-eye (visual colorimetric mode) and a smartphone (RGB readout mode) simultaneously. The accuracy and potential application for field analysis were further confirmed by the analysis of two water samples, four honey samples and two certified reference water samples (BWB2440-2016 and GBW08650), good recoveries (90-116%) were obtained for those samples and their spiked samples.

5.
Food Chem ; 414: 135755, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36841101

RESUMO

In this paper, Co-doped NiMoO4 nanorods with oxygen vacancies are synthesized on carbon cloth (Co-NiMoO4 NRs/CC) via microplasma and quenching-induced method.Owing to the surface defects and metal ion doping, the electronic structure and surface properties of the catalyst are tuned.Cyclic voltammetry (CV) and amperometry are used to investigate the electrocatalytic behavior of the glucose sensor in an alkaline medium with sensitivities of 7411 and 3125 µA L mmol-1 cm-2 in the linear range 1.0 µmol L-1 to 1.0 mmol L-1 and 1.0 mmol L-1 to 7.0 mmol L-1, respectively. The detection limit is 0.079 µmol L-1 at S/N = 3. Moreover, the as-prepared catalyst electrode is also successfully used in real food and serum samples, with a recovery rate of 97.1%-107.4%.The DFT calculations show that the Co site of the catalyst significantly influenced glucose sensing performance. This idea expands the application of quenching chemistry in electrochemical sensing.


Assuntos
Glucose , Nanotubos , Limite de Detecção , Nanotubos/química , Carbono/química , Níquel/química , Eletrodos , Técnicas Eletroquímicas/métodos
6.
Anal Methods ; 15(3): 304-310, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36546428

RESUMO

In this study, a 3D surface-folded composite was prepared in situ as a hydrazine sensor by loading a hybrid film of CoNi-layered double hydroxides (LDHs) with nitrogen-doped carbon dots on self-assembled ZnO microspheres. The nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), and the electrochemical behavior of the sensors was investigated by cyclic voltammetry (CV), amperometry and electrochemical impedance spectroscopy (EIS). The results showed that ZnO microspheres with nitrogen-doped carbon dots strongly coupled with LDHs can significantly reduce the charge transfer resistance, accelerate the oxidation kinetics of hydrazine, and effectively increase the electrochemically active surface area (ECSA). The sensor achieved ultra-sensitive (13 040 µA mM-1 cm-2 (S/N = 3)) detection of hydrazine in the concentration range of 0.7 µM to 4 mM, exhibited excellent selectivity, reproducibility and high stability, and was successfully applied to the determination of hydrazine in actual environmental water samples and landfill leachate samples.


Assuntos
Caramujo Conus , Óxido de Zinco , Animais , Carbono/química , Óxido de Zinco/química , Reprodutibilidade dos Testes , Hidrazinas , Nitrogênio
7.
Food Chem ; 407: 135144, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493474

RESUMO

The rational design of high-efficiency catalysts for non-enzymatic glucose sensing is extremely important for the timely and effective monitoring of glucose content in beverages and human blood. A 3D bimetallic organic framework (Coordination Polymer of Oslo, CPO) nanorod array with oxygen vacancies was green fabricated on carbon cloth (Ni0.5Co0.5-CPO-27 NRA/CC) using dielectric barrier discharge (DBD) microplasma for the first time. Density functional theory (DFT) calculations demonstrated that the oxygen vacancy of Ni0.5Co0.5-CPO-27 can be effectively induced under DBD microplasma conditions. Based on the 3D nanorod arrays with rich oxygen vacancies and bimetallic synergistic effects, as a non-enzyme glucose sensor, the Ni0.5Co0.5-CPO-27 electrode exhibited a sensitivity of 8499.5 µA L/mmol cm-2 and 3239.2 µA L/mmol cm-2 and a limit of detection (LOD) of 0.16 µmol/L (S/N = 3). It has been successfully applied to the determination of glucose levels in real samples such as cola, green tea and human serum.


Assuntos
Técnicas Biossensoriais , Nanotubos , Humanos , Oxigênio , Glucose , Bebidas
8.
Anal Chim Acta ; 1237: 340631, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442944

RESUMO

Composited carbon nanomaterials have attracted wide attention and are used for high-sensitivity biological assays due to their low toxicity, good biocompatibility, and excellent electrical conductivity. To further promote electron transfer and enhance electrocatalytic activity to detect dopamine (DA), this study proposed carbon dots (CDs) based on glycerol synthesized by liquid dielectric barrier discharge (DBD) microplasma. Combined with the multi-walled carbon nanotubes (MWCNTs) with excellent electrical conductivity, a composited carbon nanomaterial electrode of CDs/MWCNTs was constructed. As a DA biosensor, the interaction and electron exchange between MWCNTs, CDs, and DA can be enhanced thanks to the π-π stacking force, thereby facilitating the sensitive electrochemical detection of DA. The sensor exhibits good sensing performance toward DA detection with a linear range of 2.0-100 µM, a limit of detection (LOD) of 11.08 nM (S/N = 3), and a sensitivity of 29020 µA cm-2 mM-1. The proposed electrode successfully detected DA levels in human serum samples with satisfactory selectivity and recovery rate. The microplasma-enabled synthesized method provides a promising path for preparing and applying carbon-based nanomaterials.


Assuntos
Dopamina , Nanotubos de Carbono , Humanos , Eletrodos , Condutividade Elétrica , Limite de Detecção
9.
Food Chem ; 393: 133399, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35679705

RESUMO

In this work, a 3D ultra-thin NiCo-LDH nanosheet array coated Cu nanoparticles on carbon cloth (NiCo-LDH@Cu NSA/CC) was ultrafast synthesized by plasma magnetron sputtering for the first time. This method has low toxicity and is easy to operate. As a durable and efficient 3D heteronanoarray electrocatalyst for glucose detection, NiCo-LDH@Cu NSA/CC has higher stable conductivity and faster electron transport rate than NiCo-LDH NSA/CC and Cu nanoparticles, which work through synergistic effect to form a high-performance sensing platform. The NiCo-LDH@Cu NSA/CC heteronanosheet structure has good electrocatalytic performance for glucose oxidation, with the sensitivity of the two linear ranges (0.001-1 mmol L-1 and 1-6 mmol L-1) being 9710 µA L mmol-1 cm-2 and 4870 µA L mmol-1 cm-2, respectively, and the detection limit (LOD) is 157 nmol L-1 (S/N = 3). The sensor has been successfully applied to detect glucose in beverages and serum.


Assuntos
Carbono , Glucose , Bebidas , Carbono/química , Glucose/química , Humanos , Oxirredução , Soro
10.
Anal Chim Acta ; 1192: 339366, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35057941

RESUMO

A miniaturized/portable visual colorimetric system based on hydride generation headspace solid phase extraction (HG-HS-SPE) was proposed for arsenic detection by naked eyes. As(III) was transformed into AsH3via hydride generation process, the volatile AsH3 was introduced into reaction bottle and reacted with AgNO3 subsequently. Silver nanoparticles (Ag NPs) were generated in situ, resulting in the color changed from white to black, it could be readout by naked eyes or a smartphone application (color extraction, for RGB readout). The interferences from 9 common ions and 10 conventional hydride generation elements were discussed, the results demonstrated that the proposed method exhibit a good anti-interference. The proposed visual colorimetric method was further applied to seven water samples and their spiked samples, and a certified reference water sample (GBW08605) for demonstrating its accuracy and applicability.


Assuntos
Arsênio , Nanopartículas Metálicas , Colorimetria , Prata , Água
11.
Plant Physiol Biochem ; 167: 806-815, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34530325

RESUMO

The red light (R) to far-red light (FR) ratio (R:FR) regulates plant responses to salt stress, but the regulation mechanism is still unclear. In this study, tomato seedlings were grown under half-strength Hoagland solution with or without 150 mM NaCl at two different R:FR ratios (7.4 and 0.8). The photosynthetic capacity, antioxidant enzyme activities, and the phenotypes at chloroplast ultrastructure and whole plant levels were investigated. The results showed that low R:FR significantly alleviated the damage of tomato seedlings from salt stress. On day 4, 8, and 12 at low R:FR, the maximum photochemical quantum yields (Fv/Fm) of photosystem II (PSII) were increased by 4.53%, 3.89%, and 16.49%, respectively; the net photosynthetic rates (Pn) of leaves were increased by 16.21%, 90.81%, and 118.00%, respectively. Low R:FR enhanced the integrity and stability of the chloroplast structure of salinity-treated plants through maintaining the high activities of antioxidant enzymes and mitigated the degradation rate of photosynthetic pigments caused by reactive oxygen species (ROS) under salt stress. The photosynthesis, antioxidant enzyme-related gene expression, and transcriptome sequencing analysis of tomato seedlings under different treatments were also investigated. Low R:FR promoted the de novo synthesis of D1 protein via triggering psbA expression, and upregulated the transcripts of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) related genes. Meanwhile, the transcriptome analysis confirmed the positive function of low R:FR on enhancing tomato salinity stress tolerance from the regulation of photosynthesis and ROS scavenging systems.


Assuntos
Tolerância ao Sal , Solanum lycopersicum , Antioxidantes , Fotossíntese , Folhas de Planta , Plântula
12.
Front Plant Sci ; 12: 650068, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025696

RESUMO

Photoperiod is a crucial inducer of plant flowering. Cycling DOF factors (CDFs) play pivotal roles in the flowering of long-day (LD) and short-day (SD) plants. However, the functions of CDFs in the photoperiod regulated flowering remain unclear in day-neutral plants. In the present study, tomato (Solanum lycopersicum L. cv. "Ailsa Craig") seedlings of the wild-type and transgenic lines of overexpressing CDFs were treated with different photoperiods. The flowering time and the expression pattern of SlCDFs and other FT-like genes were investigated. The results showed that tomato SlCDF1, SlCDF2, SlCDF3, SlCDF4, and SlCDF5 are homologs to Arabidopsis cycling DOF factor 1 (AtCDF1). SlCDF1-5 expression levels were influenced by the developmental stage and the tissue location, and notably, the expression patterns throughout light environments showed two opposite trends. Among the SlCDF1-5 overexpression transgenic lines, overexpressing SlCDF3 delayed flowering time in both LD (16 h light/8 h dark) and SD (8 h light/16 h dark) conditions. Furthermore, SlCDF3 led to an increase in the mRNA level of SlSP5G, a tomato FT-like gene, in LD conditions, while the transcription level of the other two FT-like genes, SlSP5G2 and SlSP5G3, were up-regulated in SD conditions. Taken together, at the transcription level, our results demonstrated that SlCDF3 played a significant role in controlling tomato flowering under LD and SD conditions, possibly through directly or indirectly regulating FT-like genes.

13.
Front Plant Sci ; 11: 449, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351536

RESUMO

In plants, 14-3-3 proteins are recognized as mediators of signal transduction and function in both development and stress response. However, there are only a few preliminary functional researches in the C4 crop foxtail millet. Here, phylogenetic analysis categorized foxtail millet 14-3-3s (SiGRFs) into 10 discrete groups (Clusters I to X). Transcriptome and qPCR analyses showed that all the SiGRFs responded to at least one abiotic stress. All but one SiGRF-overexpressing (OE) Arabidopsis thaliana line (SiGRF1) exhibited insensitivity to abiotic stresses during seed germination and seedling growth. Compared with the Col-0 wild-type, SiGRF1-OEs had slightly lower germination rates and smaller leaves. However, flowering time of SiGRF1-OEs occurred earlier than that of Col-0 under high-salt stress. Interaction of SiGRF1 with a foxtail millet E3 ubiquitin-protein ligase (SiRNF1/2) indicates that the proteinase system might hydrolyze SiGRF1. Further investigation showed that SiGRF1 localized in the cytoplasm, and its gene was ubiquitously expressed in various tissues throughout various developmental stages. Additionally, flowering-related genes, WRKY71, FLOWERING LOCUS T, LEAFY, and FRUITFULL, in SiGRF1-OEs exhibited considerably higher expression levels than those in Col-0 under salinity-stressed conditions. Results suggest that SiGRF1 hastens flowering, thereby providing a means for foxtail millet to complete its life cycle and avoid further salt stress.

14.
Sci Rep ; 10(1): 177, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932626

RESUMO

The extensive use of chemical fertilizers poses serious collateral problems such as environmental pollution, pest resistance development and food safety decline. Researches focused on applying plant-beneficial microorganisms to partially replace chemical fertilizer use is increasing due to the requirement of sustainable agriculture development. Thus to investigate the possibility of a plant-beneficial Trichoderma strain and its bio-organic fertilizer product in saving chemical fertilizer application and in improving crop quality, a field trial and continuous pot experiments were carried out with tomato. Four treatments were set up: a reduced application of chemical fertilizer (75% of the conventional application) plus Trichoderma-enriched bio-organic fertilizer (BF), organic fertilizer (OF) or Trichoderma spore suspension (SS), with using the 100% rate of the conventional chemical fertilizer as the control (CF). The results showed that the total soluble sugar, Vitamin C and nitrate accumulations were, respectively, +up to 24%, +up to 57% and -up to 62% in the tomatoes of the BF treatment compared to those of the control (CF). And both of the pot and field trials revealed that reduced rates of chemical fertilizer plus bio-organic fertilizer produced tomato yields equivalent to those obtained using the 100% of the chemical fertilizer. However, application with the inoculant alone (SS) or combined with the organic fertilizer alone (OF) would lead to a yield decreases of 6-38% and 9-35% over the control. Since the increased abundance of soil microflora and the enhanced soil fertility frequently showed positive linear correlations especially in the BF-treated soils, we conclude that the efficacy of this bio-organic fertilizer for maintaining a stable tomato yield and improving tomato quality may be due to the improved soil microbial activity. Thus, the results suggest that the Trichoderma bio-organic fertilizer could be employed in combination with the appropriate rates of chemical fertilizers to get maximum benefits regarding yield, quality and fertilizer savings.


Assuntos
Agricultura/métodos , Fertilizantes , Doenças das Plantas/prevenção & controle , Solo/química , Solanum lycopersicum/crescimento & desenvolvimento , Trichoderma/fisiologia , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Nitrogênio , Microbiologia do Solo
15.
Physiol Plant ; 168(3): 694-708, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31376304

RESUMO

Carbon dioxide concentration (CO2 ) and light intensity are known to play important roles in plant growth and carbon assimilation. Nevertheless, the underlying physiological mechanisms have not yet been fully explored. Tomato seedlings (Solanum lycopersicum Mill. cv. Jingpeng No. 1) were exposed to two levels of CO2 and three levels of light intensity and the effects on growth, leaf gas exchange and water use efficiency were investigated. Elevated CO2 and increased light intensity promoted growth, dry matter accumulation and pigment concentration and together the seedling health index. Elevated CO2 had no significant effect on leaf nitrogen content but did significantly upregulate Calvin cycle enzyme activity. Increased CO2 and light intensity promoted photosynthesis, both on a leaf-area basis and on a chlorophyll basis. Increased CO2 also increased light-saturated maximum photosynthetic rate, apparent quantum efficiency and carboxylation efficiency and, together with increased light intensity, it raised photosynthetic capacity. However, increased CO2 reduced transpiration and water consumption across different levels of light intensity, thus significantly increasing both leaf-level and plant-level water use efficiency. Among the range of treatments imposed, the combination of increased CO2 (800 µmol CO2 mol-1 ) and high light intensity (400 µmol m-2 s-1 ) resulted in optimal growth and carbon assimilation. We conclude that the combination of increased CO2 and increased light intensity worked synergistically to promote growth, photosynthetic capacity and water use efficiency by upregulation of pigment concentration, Calvin cycle enzyme activity, light energy use and CO2 fixation. Increased CO2 also lowered transpiration and hence water usage.


Assuntos
Dióxido de Carbono/farmacologia , Luz , Fotossíntese , Solanum lycopersicum/fisiologia , Clorofila/fisiologia , Solanum lycopersicum/efeitos da radiação , Folhas de Planta/fisiologia , Transpiração Vegetal , Plântula
16.
Genes (Basel) ; 10(9)2019 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-31470680

RESUMO

Plants grown under highly variable natural light regimes differ strongly from plants grown under constant light (CL) regimes. Plant phenotype and adaptation responses are important for plant biomass and fitness. However, the underlying regulatory mechanisms are still poorly understood, particularly from a transcriptional perspective. To investigate the influence of different light regimes on tomato plants, three dynamic light (DL) regimes were designed, using a CL regime as control. Morphological, photosynthetic, and transcriptional differences after five weeks of treatment were compared. Leaf area, plant height, shoot /root weight, total chlorophyll content, photosynthetic rate, and stomatal conductance all significantly decreased in response to DL regimes. The biggest expression difference was found between the treatment with the highest light intensity at the middle of the day with a total of 1080 significantly up-/down-regulated genes. A total of 177 common differentially expressed genes were identified between DL and CL conditions. Finally, significant differences were observed in the levels of gene expression between DL and CL treatments in multiple pathways, predominantly of plant-pathogen interactions, plant hormone signal transductions, metabolites, and photosynthesis. These results expand the understanding of plant development and photosynthetic regulations under DL conditions by multiple pathways.


Assuntos
Solanum lycopersicum/genética , Luz Solar , Transcriptoma , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efeitos da radiação , Fotoperíodo , Fotossíntese
17.
Front Plant Sci ; 10: 863, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31333702

RESUMO

Salinity-alkalinity stress has caused severe environment problems that negatively impact the growth and development of watermelon (Citrullus lanatus L.). In this study, watermelon seedlings were inoculated with the arbuscular mycorrhizal fungi (AMF) Funneliformis mosseae to investigate its effect on watermelon growth and development. The main measurements included morphological traits, elemental and water uptake, the level of reactive oxygen species, antioxidant enzyme and photosynthesis activities, and relative expression levels of stress response genes. Under salinity-alkalinity stresses, watermelon morphological traits, elemental and water uptake were all significantly alleviated after incubation with AMF. Antioxidant abilities of watermelon were significantly improved after incubation with AMF in salinity-alkalinity stresses. Under normal conditions, all photosynthesis related parameters were significantly increased after incubation of AMF. In contrast, they were all significantly reduced under salinity-alkalinity stresses and were all significantly alleviated after incubation of AMF. Salinity-alkalinity stresses impacted the chloroplast structure and AMF significantly alleviated these damages. Under salinity-alkalinity stresses, the relative expression level of RBCL was significantly reduced and was significantly alleviated after AMF treatment. The relative expression level of PPH was significantly increased and was further significantly reduced after AMF treatment. For the relative expression levels of antioxidant response related genes Cu-Zn SOD, CAT, APX, GR, their relative expression levels were significantly increased and were further significantly increased after AMF treatment. Our study demonstrated the beneficial effects of AMF under salinity-alkalinity stresses, which could be implicated in the management of watermelon cultivation under salinity-alkalinity regions.

18.
BMC Plant Biol ; 18(1): 158, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30081827

RESUMO

BACKGROUND: Phytochromes are dimeric proteins with critical roles in perceiving day length and the environmental signals that trigger flowering. Night break (NB) and the red to far-red light ratio (R:FR) have been used extensively as tools to study the photoperiodic control of flowering. However, at the molecular level, little is known about the effect of NB and different R:FR values on flowering in day-neutral plants (DNPs) such as tomato. RESULTS: Here, we show that tomato SP5G, SP5G2, and SP5G3 are homologs of Arabidopsis thaliana FLOWERING LOCUS T (FT) that repress flowering in Nicotiana benthamiana. NB every 2 h at intensities of 10 µmol m- 2 s- 1 or lower R:FR (e.g., 0.6) caused a clear delay in tomato flowering and promoted SP5G mRNA expression. The promoted SP5G mRNA expression induced by red light NB and low R:FR treatments was reversed by a subsequent FR light stimulus or a higher R:FR treatment. The tomato phyB1 mutation abolished the effects of NB and lower R:FR treatments on flowering and SP5G mRNA expression, indicating that the effects were mediated by phytochrome B1 in tomato. CONCLUSION: Our results strongly suggest that SP5G mRNA suppression is the principal cause of NB and lower R:FR effects on flowering in tomato.


Assuntos
Flores/crescimento & desenvolvimento , Fitocromo B/fisiologia , Proteínas de Plantas/fisiologia , Solanum lycopersicum/crescimento & desenvolvimento , Fatores de Transcrição/fisiologia , Arabidopsis , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Luz , Solanum lycopersicum/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Nicotiana , Fatores de Transcrição/genética
19.
J Craniofac Surg ; 29(7): e690-e693, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30157143

RESUMO

This study demonstrated the application of transmasseteric anterior parotid approach for open reduction of mandibular subcondylar fractures depending on the basis of the anatomical study of the temporomandibular joint and parotid gland area. The anatomical study was performed on 5 Chinese adult cadavers fixed by 10% formalin. The temporomandibular joints and parotid regions were studied. In the clinical study, 26 patients with mandibular subcondylar fractures were recruited between July 2014 and December 2017. All 26 patients with mandibular subcondylar fractures received satisfactory occlusions and normal mouth opening: no postoperative facial paralysis occurred in these patients. It is crucial to know the anatomy of both temporomandibular joint and parotid region for reducing significantly the surgical trauma and complications. Transmasseteric anterior parotid approach is a feasible approach for the surgical treatment of the mandibular subcondylar fractures. This method can provide adequate exposure, minimal facial nerve injury, open reduction easily, and inconspicuous scarring.


Assuntos
Fixação Interna de Fraturas/métodos , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/cirurgia , Adolescente , Adulto , Placas Ósseas , Feminino , Humanos , Masculino , Côndilo Mandibular/lesões , Adulto Jovem
20.
BMC Plant Biol ; 18(1): 92, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29793435

RESUMO

BACKGROUND: Red (R) and far-red (FR) light distinctly influence phytochrome-mediated initial tomato growth and development, and more recent evidence indicates that these spectra also modulate responses to a multitude of abiotic and biotic stresses. This research investigated whether different R: FR values affect tomato growth response and salinity tolerance. Tomato seedlings were exposed to different R: FR conditions (7.4, 1.2 and 0.8) under salinity stress (100 mM NaCl), and evaluated for their growth, biochemical changes, active reactive oxygen species (ROS) and ROS scavenging enzymes, pigments, rate of photosynthesis, and chlorophyll fluorescence. RESULTS: The results showed that under conditions of salinity, tomato seedlings subjected to a lower R: FR value (0.8) significantly increased both their growth, proline content, chlorophyll content and net photosynthesis rate (Pn), while they decreased malondialdehyde (MDA) compared to the higher R: FR value (7.4). Under conditions of salinity, the lower R: FR value caused a decrease in both the superoxide anion (O2•-) and in hydrogen peroxide (H2O2) generation, an increase in the activities of superoxidase dismutase (SOD, EC 1.15.1.1), peroxidase (POD, EC 1.11.1.7) and catalase (CAT, EC 1.11.1.7). Tomato seedlings grown under the lower R: FR value and conditions of salinity showed a higher actual quantum yield of photosynthesis (ΦPSII), electron transport rate (ETR), and photochemical quenching (qP) than those exposed to a higher R: FR, indicating overall healthier growth. However, the salinity tolerance induced at the lower R: FR condition disappeared in the tomato phyB1 mutant. CONLUSION: These results suggest that growing tomato with a lower R: FR value could improve seedlings' salinity tolerance, and phytochrome B1 play an very important role in this process. Therefore, different qualities of light can be used to efficiently develop abiotic stress tolerance in tomato cultivation.


Assuntos
Solanum lycopersicum/fisiologia , Antioxidantes/metabolismo , Clorofila/metabolismo , Fluorescência , Sequestradores de Radicais Livres/metabolismo , Peróxido de Hidrogênio/metabolismo , Raios Infravermelhos , Solanum lycopersicum/efeitos da radiação , Malondialdeído/metabolismo , Peroxidases/metabolismo , Fotossíntese , Fitocromo/metabolismo , Prolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Salinidade , Estresse Salino , Tolerância ao Sal
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