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1.
Plant Cell Environ ; 47(2): 429-441, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37916615

RESUMO

The ratio of red light to far-red light (R:FR) is perceived by light receptors and consequently regulates plant architecture. Regulation of shoot branching by R:FR ratio involves plant hormones. However, the roles of strigolactone (SL), the key shoot branching hormone and the interplay of different hormones in the light regulation of shoot branching in tomato (Solanum lycopersicum) are elusive. Here, we found that defects in SL synthesis genes CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7) and CCD8 in tomato resulted in more lateral bud growth but failed to reverse the FR inhibition of lateral bud growth, which was associated with increased auxin synthesis and decreased synthesis of cytokinin (CK) and brassinosteroid (BR). Treatment of auxin also inhibited shoot branching in ccd mutants. However, CK released the FR inhibition of lateral bud growth in ccd mutants, concomitant with the upregulation of BR synthesis genes. Furthermore, plants that overexpressed BR synthesis gene showed more lateral bud growth and the shoot branching was less sensitive to the low R:FR ratio. The results indicate that SL synthesis is dispensable for light regulation of shoot branching in tomato. Auxin mediates the response to R:FR ratio to regulate shoot branching by suppressing CK and BR synthesis.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Luz Vermelha , Brotos de Planta/metabolismo , Citocininas , Lactonas , Ácidos Indolacéticos , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Appl Clin Med Phys ; 25(4): e14258, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38175960

RESUMO

PURPOSE: We aimed to perform the commissioning and clinical evaluation of myQA SRS detector array for patient-specific quality assurance (PSQA) of stereotactic radiosurgery (SRS)/ stereotactic body radiotherapy (SBRT) plans. METHODS: To perform the commissioning of myQA SRS, its dose linearity, dose-rate dependence, angular dependence, and field-size dependence were investigated. Ten SBRT plans were selected for clinical evaluation: 1) Common clinical deviations based on the original SBRT plan (Plan0), including multileaf collimator (MLC) positioning deviation and treatment positioning deviation were introduced. 2) Compared the performance of the myQA SRS and a high-resolution EPID dosimetry system in PSQA measurement for the SBRT plans. Evaluation parameters include gamma passing rate (GPR) and distance-to-agreement (DTA) pass rate (DPR). RESULTS: The dose linearity, angle dependence, and field-size dependence of myQA SRS system exhibit excellent performance. The myQA SRS is highly sensitive in the detection of MLC deviations. The GPR of (3%/1 mm) decreases from 90.4% of the original plan to 72.7%/62.9% with an MLC outward/inward deviation of 3 mm. Additionally, when the setup error deviates by 1 mm in the X, Y, and Z directions with the GPR of (3%/1 mm) decreasing by an average of -20.9%, -25.7%, and -24.7%, respectively, and DPR (1 mm) decreasing by an average of -33.7%, -32.9%, and -29.8%. Additionally, the myQA SRS has a slightly higher GPR than EPID for PSQA, However, the difference is not statistically significant with the GPR of (3%/1 mm) of (average 90.4%% vs. 90.1%, p = 0.414). CONCLUSION: Dosimetry characteristics of the myQA SRS device meets the accuracy and sensitivity requirement of PSQA for SRS/SBRT treatment. The dose rate dependence should be adequately calibrated before its application and a more stringent GPR (3%/1 mm) evaluation criterion is suggested when it is used for SRS/SBRT QA.


Assuntos
Radiocirurgia , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Imagens de Fantasmas , Radiometria
3.
Plant Biotechnol J ; 21(1): 219-231, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36204970

RESUMO

The post-translational modification of proteins enables cells to respond promptly to dynamic stimuli by controlling protein functions. In higher plants, SPINDLY (SPY) and SECRET AGENT (SEC) are two prominent O-glycosylation enzymes that have both unique and overlapping roles; however, the effects of their O-glycosylation on fruit ripening and the underlying mechanisms remain largely unknown. Here we report that SlSPY affects tomato fruit ripening. Using slspy mutants and two SlSPY-OE lines, we provide biological evidence for the positive role of SlSPY in fruit ripening. We demonstrate that SlSPY regulates fruit ripening by changing the ethylene response in tomato. To further investigate the underlying mechanism, we identify a central regulator of ethylene signalling ETHYLENE INSENSITIVE 2 (EIN2) as a SlSPY interacting protein. SlSPY promotes the stability and nuclear accumulation of SlEIN2. Mass spectrometry analysis further identified that SlEIN2 has two potential sites Ser771 and Thr821 of O-glycans modifications. Further study shows that SlEIN2 is essential for SlSPY in regulating fruit ripening in tomatoes. Collectively, our findings reveal a novel regulatory function of SlSPY in fruit and provide novel insights into the role of the SlSPY-SlEIN2 module in tomato fruit ripening.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Frutas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas/genética
4.
J Pineal Res ; 74(3): e12858, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36732033

RESUMO

Increasing carbon dioxide (CO2 ) promotes photosynthesis and mitigates heat stress-induced deleterious effects on plants, but the regulatory mechanisms remain largely unknown. Here, we found that tomato (Solanum lycopersicum L.) plants treated with high atmospheric CO2 concentrations (600, 800, and 1000 µmol mol-1 ) accumulated increased levels of melatonin (N-acetyl-5-methoxy tryptamine) in their leaves and this response is conserved across many plant species, including Arabidopsis, rice, wheat, mustard, cucumber, watermelon, melon, and hot pepper. Elevated CO2 (eCO2 ; 800 µmol mol-1 ) caused a 6.8-fold increase in leaf melatonin content, and eCO2 -induced melatonin biosynthesis preferentially occurred through chloroplast biosynthetic pathways in tomato plants. Crucially, manipulation of endogenous melatonin levels by genetic means affected the eCO2 -induced accumulation of sugar and starch in tomato leaves. Furthermore, net photosynthetic rate, maximum photochemical efficiency of photosystem II, and transcript levels of chloroplast- and nuclear-encoded photosynthetic genes, such as rbcL, rbcS, rbcA, psaD, petB, and atpA, significantly increased in COMT1 overexpressing (COMT1-OE) tomato plants, but not in melatonin-deficient comt1 mutants at eCO2 conditions. While eCO2 enhanced plant tolerance to heat stress (42°C) in wild-type and COMT1-OE, melatonin deficiency compromised eCO2 -induced thermotolerance in comt1 plants. The expression of heat shock proteins genes increased in COMT1-OE but not in comt1 plants in response to eCO2 under heat stress. Further analysis revealed that eCO2 -induced thermotolerance was closely linked to the melatonin-dependent regulation of reactive oxygen species, redox homeostasis, cellular protein protection, and phytohormone metabolism. This study unveiled a crucial mechanism of elevated CO2 -induced thermotolerance in which melatonin acts as an essential endogenous signaling molecule in tomato plants.


Assuntos
Melatonina , Solanum lycopersicum , Termotolerância , Dióxido de Carbono/metabolismo , Fotossíntese
5.
J Appl Clin Med Phys ; 24(11): e14097, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37438966

RESUMO

PURPOSE: This study aimed to assess the effects of bladder filling during cervical cancer radiotherapy on target volume and organs at risk (OARs) dose based on daily computed tomography (daily-CT) images and provide bladder-volume-based dose prediction models. METHODS: Nineteen patients (475 daily-CTs) comprised the study group, and five patients comprised the validation set (25 daily-CTs). Target volumes and OARs were delineated on daily-CT images and the treatment plan was recalculated accordingly. The deviation from the planning bladder volume (DVB), the correlation between DVB and clinical (CTV)/planning (PTV) target volume in terms of prescribed dose coverage, and the relationship of small bowel volume and bladder dose with the ratio of bladder volume (RVB) were analyzed. RESULTS: In all cases, the prescribed dose coverage in the CTV was >95% when DVB was <200 cm3 , whereas that in the PTV was >95% when RVB was <160%. The ratio of bladder V45 Gy to the planning bladder V45 Gy (RBV45 ) exhibited a negative linear relationship with RVB (RBV45  = -0.18*RVB + 120.8; R2  = 0.80). Moreover, the ratio of small bowel volume to planning small bowel volume (RVS) exhibited a negative linear relationship with RVB (RVS = -1.06*RVB +217.59; R2  = 0.41). The validation set results showed that the linear model predicted well the effects of bladder volume changes on target volume coverage and bladder dose. CONCLUSIONS: This study assessed dosimetry and volume effects of bladder filling on target and OARs based on daily-CT images. We established a quantitative relationship between these parameters, providing dose prediction models for cervical cancer radiotherapy.


Assuntos
Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero , Feminino , Humanos , Bexiga Urinária/diagnóstico por imagem , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Tomografia Computadorizada por Raios X , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco
6.
New Phytol ; 236(3): 989-1005, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35892173

RESUMO

Natural variations in cis-regulatory regions often affect crop phenotypes by altering gene expression. However, the mechanism of how promoter mutations affect gene expression and crop stress tolerance is still poorly understood. In this study, by analyzing RNA-sequencing (RNA-Seq) data and reverse transcription quantitative real-time PCR validation in the cultivated tomato and its wild relatives, we reveal that the transcripts of WRKY33 are almost unchanged in cold-sensitive cultivated tomato Solanum lycopersicum L. 'Ailsa Craig' but are significantly induced in cold-tolerant wild tomato relatives Solanum habrochaites LA1777 and Solanum pennellii LA0716 under cold stress. Overexpression of SlWRKY33 or ShWRKY33 positively regulates cold tolerance in tomato. Variant of the critical W-box in SlWRKY33 promoter results in the loss of self-transcription function of SlWRKY33 under cold stress. Analysis integrating RNA-Seq and chromatin immunoprecipitation sequencing data reveals that SlWRKY33 directly targets and induces multiple kinases, transcription factors, and molecular chaperone genes, such as CDPK11, MYBS3, and BAG6, thus enhancing cold tolerance. In addition, heat- and Botrytis-induced WRKY33s expression in both wild and cultivated tomatoes are independent of the critical W-box variation. Our findings suggest nucleotide polymorphism in cis-regulatory regions is crucial for different cold sensitivity between cultivated and wild tomato plants.


Assuntos
Solanum lycopersicum , Solanum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Chaperonas Moleculares/metabolismo , RNA/metabolismo , Solanum/genética , Solanum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas
7.
New Phytol ; 233(4): 1900-1914, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34839530

RESUMO

Light quality affects mutualisms between plant roots and arbuscular mycorrhizal fungi (AMFs), which modify nutrient acquisition in plants. However, the mechanisms by which light systemically modulates root colonization by AMFs and phosphate uptake in roots remain unclear. We used a range of approaches, including grafting techniques, protein immunoblot analysis, electrophoretic mobility shift assay, chromatin immunoprecipitation, and dual-luciferase assays, to unveil the molecular basis of light signal transmission from shoot to root that mediates arbuscule development and phosphate uptake in tomato. The results show that shoot phytochrome B (phyB) triggers shoot-derived mobile ELONGATED HYPOCOTYL5 (HY5) protein accumulation in roots, and HY5 further positively regulates transcription of strigolactone (SL) synthetic genes, thus forming a shoot phyB-dependent systemic signaling pathway that regulates the synthesis and accumulation of SLs in roots. Further experiments with carotenoid cleavage dioxygenase 7 mutants and supplementary red light confirm that SLs are indispensable in the red-light-regulated mycorrhizal symbiosis in roots. Our results reveal a phyB-HY5-SLs systemic signaling cascade that facilitates mycorrhizal symbiosis and phosphate utilization in plants. The findings provide new prospects for the potential application of AMFs and light manipulation to effectively improve nutrient utilization and minimize the use of chemical fertilizers and associated pollution.


Assuntos
Micorrizas , Solanum lycopersicum , Compostos Heterocíclicos com 3 Anéis , Lactonas/metabolismo , Solanum lycopersicum/genética , Micorrizas/fisiologia , Raízes de Plantas/metabolismo , Simbiose
8.
J Pineal Res ; 72(3): e12792, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174545

RESUMO

Melatonin functions in multiple aspects of plant growth, development, and stress response. Nonetheless, the mechanism of melatonin in plant carbon metabolism remains largely unknown. In this study, we investigated the influence of melatonin on the degradation of starch in tomato leaves. Results showed that exogenous melatonin attenuated carbon starvation-induced chlorophyll degradation and leaf senescence. In addition, melatonin delayed leaf starch degradation and inhibited the transcription of starch-degrading enzymes after sunset. Interestingly, melatonin-alleviated symptoms of leaf senescence and starch degradation were compromised when the first key gene for starch degradation, α-glucan water dikinase (GWD), was overexpressed. Furthermore, exogenous melatonin significantly upregulated the transcript levels of several microRNAs, including miR171b. Crucially, the GWD gene was identified as a target of miR171b, and the overexpression of miR171b ameliorated the carbon starvation-induced degradation of chlorophyll and starch, and inhibited the expression of the GWD gene. Taken together, these results demonstrate that melatonin promotes plant tolerance against carbon starvation by upregulating the expression of miR171b, which can directly inhibit GWD expression in tomato leaves.


Assuntos
Melatonina , Solanum lycopersicum , Clorofila/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Melatonina/metabolismo , Melatonina/farmacologia , Folhas de Planta/metabolismo , Senescência Vegetal
9.
Angew Chem Int Ed Engl ; 60(18): 10137-10146, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33501698

RESUMO

Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance of all-polymer solar cells (all-PSCs). Different from our recent work about fluoro- and bromo- co-modified end group of IC-FBr (a mixture of IC-FBr1 and IC-FBr2), in this paper, we synthesized and purified two regiospecific fluoro- and bromo- substituted end groups (IC-FBr-o & IC-FBr-m), which were then employed to construct two regio-regular polymer acceptors named PYF-T-o and PYF-T-m, respectively. In comparison with its isomeric counterparts named PYF-T-m with different conjugated coupling sites, PYF-T-o exhibits stronger and bathochromic absorption to achieve better photon harvesting. Meanwhile, PYF-T-o adopts more ordered inter-chain packing and suitable phase separation after blending with the donor polymer PM6, which resulted in suppressed charge recombination and efficient charge transport. Strikingly, we observed a dramatic performance difference between the two isomeric polymer acceptors PYF-T-o and PYF-T-m. While devices based on PM6:PYF-T-o can yield power conversion efficiency (PCE) of 15.2 %, devices based on PM6:PYF-T-m only show poor efficiencies of 1.4 %. This work demonstrates the success of configuration-unique fluorinated end groups in designing high-performance regular polymer acceptors, which provides guidelines towards developing all-PSCs with better efficiencies.

10.
Plant Cell Environ ; 42(12): 3326-3339, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31329293

RESUMO

Plant glutamate receptor-like (GLR) genes play important roles in plant development and immune response. However, the functions of GLRs in abiotic stress response remain unclear. Here we show that cold acclimation at 12°C induced the transcripts of GLR3.3 and GLR3.5 with increased tolerance against a subsequent chilling at 4 °C. Silencing of GLR3.3 or/and GLR3.5 or application of the antagonist of ionotropic glutamate receptor 6,7-dinitroquinoxaline-2,3-dione (DNQX), all compromised the acclimation-induced increases in the transcripts of respiratory burst oxidase homolog1 (RBOH1), activity of NADPH oxidase, the accumulation of apoplastic H2 O2 and the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG), resulting in an attenuated chilling tolerance; the effect, however, was rescued by foliar application of H2 O2 or GSH. Both RBOH1-silenced and glutathione biosynthesis genes, γ- glutamylcysteine synthetase (GSH1)- and glutathione synthetase (GSH2)-cosilenced plants had decreased chilling tolerance with reduced GSH/GSSG ratio. Moreover, application of DNQX had little effects on the GSH/GSSG ratio and the tolerance in RBOH1-silenced plants and GSH1- and GSH2-cosilenced plants. These findings unmasked the functional hierarchy of GLR-H2 O2 -glutathione cascade and shed new light on cold response pathway in tomato plants.


Assuntos
Aclimatação/fisiologia , Temperatura Baixa , Homeostase , Peróxido de Hidrogênio/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/fisiologia , Aclimatação/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Glutationa/metabolismo , Homeostase/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/genética , Oxirredução/efeitos dos fármacos , Proteínas de Plantas/genética , Quinoxalinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos
11.
Ecotoxicol Environ Saf ; 169: 911-917, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597791

RESUMO

Selenium (Se) is an essential microelement for humans and a beneficial element for plants. Recently, biofortification with Se has emerged as a key strategy to increase crop Se content. Nonetheless, Se species matters a lot as inorganic Se species is mostly toxic to human health. In this study, we investigated the effects of different forms and mode of Se application on Se accumulation and speciation in rice. The results showed that root application of Se remarkably increased Se accumulation, photosynthetic rate, biomass accumulation and tolerance to cadmium stress in rice as compared to foliar application. However, the stimulatory effects of Se varied depending on the Se species used for root feeding. At vegetative stage, root application of Se-(Methyl) selenocysteine caused the highest water extractable Se content in leaves with major contribution from organic Se species such as Se-amino acid and non-amino acid organic Se. Further investigation at reproductive stage revealed that foliar application of sodium selenite (Na2SeO3) resulted in the highest total Se content in rice seeds which was largely attributed to inorganic Se. In contrast, the root application of Na2SeO3 led to the maximum accumulation of organic Se compounds which are advantageous to human health. Moreover, the root application of Se increased antioxidant capacity and selectively enhanced amino acids and essential element content in rice grain. This study deepens our understanding of the Se species in Se-enriched rice and suggests that root application of Se may ensure the safe intake of Se through rice.


Assuntos
Oryza/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Compostos de Selênio/farmacologia , Cádmio/toxicidade , Grão Comestível/efeitos dos fármacos , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Humanos , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Compostos de Selênio/metabolismo
12.
Cancer Sci ; 109(3): 751-763, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29266526

RESUMO

To clarify the optimal cumulative cisplatin dose (CCD) in locoregionally-advanced nasopharyngel carcinoma (NPC) patients receiving induction chemotherapy (IC) plus concurrent chemoradiotherapy (CCRT). Using the NPC-specific database from the established big-data intelligence platform at Sun Yat-Sen University Cancer Center, 583 non-disseminated, locoregionally-advanced NPC patients receiving IC plus CCRT were enrolled. Propensity score matching (PSM) analysis was conducted to control for confounding factors. The median CCD was 160 mg/m2 after IC (range, 40-300 mg/m2 ); only 74 patients (12.7%) achieved CCD >200 mg/m2 . Patients receiving >200 mg/m2 CCD did not show significantly improved 5-year overall survival (OS) (HR = 1.19; 95% confidence intervals [CI] 0.69-2.06, P = .53) and progression-free survival (PFS) (HR = 1.03; 95% CI: 0.63-1.68, P = .92) compared with patients receiving <200 mg/m2 CCD. Further investigations of the potential of median CCD (160 mg/m2 ) to yield survival benefits revealed that there were no significant differences in survival endpoints between patients receiving CCD >160 mg/m2 and CCD < 160 mg/m2 in both the original and PSM cohorts. In addition, subgroup analysis indicated a favorable PFS, but not OS, with higher cisplatin administration in patients with pretreatment Epstein-Barr virus deoxyribonucleic acid (EBV DNA) <1000 copies/mL (HR = 0.26, 95% CI: 0.07-0.93, P = .03) and receiving <3 IC cycles (HR = 0.59, 95% CI 0.33-1.07, P = .08). Our analysis of real world data provided references for the optimal CCD in locoregionally-advanced NPC receiving additional IC. The causal relationship between 200 mg/m2 CCD and improved survival was not defined; 160 mg/m2 CCD might be enough. However, for patients with EBV DNA <1000 copy/mL and receiving <3 IC cycles, a higher dose might be necessary.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma/tratamento farmacológico , Cisplatino/administração & dosagem , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Quimioterapia de Indução/métodos , Neoplasias Nasofaríngeas/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/farmacologia , Carcinoma/radioterapia , Carcinoma/virologia , Quimiorradioterapia , Cisplatino/farmacologia , Bases de Dados Factuais , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Infecções por Vírus Epstein-Barr/radioterapia , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/efeitos dos fármacos , Herpesvirus Humano 4/genética , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/virologia , Resultado do Tratamento , Adulto Jovem
13.
Small ; 14(10)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29285900

RESUMO

To develop high-performance sodium-ion batteries (NIBs), electrodes should possess well-defined pathways for efficient electronic/ionic transport. In this work, high-performance NIBs are demonstrated by designing a 3D interconnected porous structure that consists of N, S co-doped 3D porous graphene frameworks (3DPGFs-NS). The most typical electrode materials (i.e., Na3 V2 (PO4 )3 (NVP), MoS2 , and TiO2 ) are anchored onto the 3DPGFs-NS matrix (denoted as NVP@C@3DPGFs-NS; MoS2 @C@3DPGFs-NS and TiO2 @C@3DPGFs-NS) to demonstrate its general process to boost the energy density of NIBs. The N, S co-doped porous graphene structure with a large surface area offers fast ionic transport within the electrode and facilitates efficient electron transport, and thus endows the 3DPGFs-NS-based composite electrodes with excellent sodium storage performance. The resulting NVP@C@3DPGFs-NS displays excellent electrochemical performance as both cathode and anode for NIBs. The MoS2 @C@3DPGFs-NS and TiO2 @C@3DPGFs-NS deliver capacities of 317 mAhg-1 at 5 Ag-1 after 1000 cycles and 185 mAhg-1 at 1 Ag-1 after 2000 cycles, respectively. The excellent long cycle life is attributed to the 3D porous structure that could greatly release mechanical stress from repeated Na+ extraction/insertion. The novel structure 3D PGFs-NS provides a general approach to modify electrodes of NIBs and holds great potential applications in other energy storage fields.

14.
Planta ; 247(5): 1217-1227, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29445868

RESUMO

MAIN CONCLUSION: N-decanoyl-homoserine lactone activates plant systemic resistance against Botrytis cinerea in tomato plants, which is largely dependent on jasmonic acid biosynthesis and signal transduction pathways. Rhizosphere bacteria secrete N-acylated-homoserine lactones (AHLs), a type of specialized quorum-sensing signal molecule, to coordinate their population density during communication with their eukaryotic hosts. AHLs behave as low molecular weight ligands that are sensed by plants and promote the host's resistance against foliar pathogens. In this study, we report on N-decanoyl-homoserine lactone (DHL), which is a type of AHL that induces systemic immunity in tomato plants and protects the host organism against the necrotrophic fungus Botrytis cinerea. Upon DHL treatment, tomato endogenous jasmonic acid (JA) biosynthesis (rather than salicylic acid biosynthesis) and signal transduction were significantly activated. Strikingly, the DHL-induced systemic resistance against B. cinerea was blocked in the tomato JA biosynthesis mutant spr2 and JA signaling gene-silenced plants. Our findings highlight the role of DHL in systemic resistance against economically important necrotrophic pathogens and suggest that DHL-induced immunity against B. cinerea is largely dependent on the JA signaling pathway. Manipulation of DHL-induced resistance is an attractive disease management strategy that could potentially be used to enhance disease resistance in diverse plant species.


Assuntos
4-Butirolactona/análogos & derivados , Botrytis , Ciclopentanos/metabolismo , Resistência à Doença/fisiologia , Homosserina/análogos & derivados , Oxilipinas/metabolismo , Doenças das Plantas/microbiologia , Transdução de Sinais , Solanum lycopersicum/microbiologia , 4-Butirolactona/metabolismo , Arabidopsis , Botrytis/metabolismo , Inativação Gênica , Homosserina/metabolismo , Solanum lycopersicum/fisiologia
15.
BMC Cancer ; 18(1): 740, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-30012115

RESUMO

BACKGROUND: Previous studies have reported radiotherapy interruption (RTI) is associated with poor local control in two-dimensional radiotherapy (2DRT) era. However, it remains unclear whether RTI still affects local control for advanced T stage (T3-4) in the intensity-modulated radiation therapy (IMRT) era. We aim to evaluate whether RTI affects local control for T3-4 NPC treated with definitive IMRT. METHODS: In this observational prospective study, 447 T3-4 NPC patients treated with IMRT plus concurrent chemotherapy were included. All patients completed the planned radiotherapy course, and RTI was defined as the actual time taken to finish the prescribed course of radiotherapy minus the planned radiotherapy time. Receiver operating characteristic (ROC) curve was used for determined the cutoff point of RTI. The effects of RTI on local control were analyzed in multivariate analysis. RESULTS: At 5 years, the local relapse-free survival (LRFS) and overall survival (OS) rates were 93.7 and 85.7%, respectively. The cutoff RTI for LRFS was 5.5 days by ROC curve. Compared to patients with RTI >  5 days, patients with RTI ≤ 5 days had a significantly lower rate of LRFS (97% vs. 83%; P < 0.001). In multivariate analysis, RTI was a risk factor independently associated with LRFS (HR = 9.64, 95% CI, 4.10-22.65), but not for OS (HR = 1.09, 95% CI, 0.84-1.64). CONCLUSIONS: The current analysis demonstrates a significant correlation between prolonged RTI and local control in NPC, even when concurrent chemotherapy is used. We consider that attention to RTI seems to be warranted for patients with advanced T-stage NPC in the era of IMRT.


Assuntos
Quimiorradioterapia , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos
16.
Cell Mol Neurobiol ; 38(3): 669-677, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28780604

RESUMO

This study was designed to examine differential expression of miR-338-5p in gliomas and the role of miR-338-5p in glioma cell invasion via its potential target gene TSHZ3 encoding Teashirt zinc finger homobox 3, predicted by bioinformatics, and matrix metallopeptidase 2 (MMP2), the key pro-invasive protease overexpressed in gliomas. Quantitative real-time reverse transcription PCR (qRT-PCR) and Spearman correlation analysis were used to determine differential expressions of miR-338-5p and TSHZ3 in astrocytic gliomas of different grades (n = 35) and glioblastoma cell lines (U87 and U251) in comparison to non-neoplastic brain (NNB) tissues (n = 6). Western blotting was used to determine the protein levels of TSHZ3 and MMP2 in glioblastoma cell lines and Matrigel invasion assay to examine the role of miR-338-5p in cell invasiveness. The results showed that the expression of miR-338-5p, normalized to hsnRNA U6, was significantly higher in grade III and IV gliomas and glioblastoma cell lines compared to that in NNB and grade II gliomas, whereas TSHZ3 expression, normalized to GAPDH, was inversely related to miR-338-5p (R = -0.636, P < 0.01). Luciferase assays showed TSHZ3 to be a target gene of miR-338-5p. In both U87 and U251 cells, miR-338-5p mimics increased MMP2 and invasiveness of the cells. Overexpression of ectopic TSHZ3 suppressed the cell invasiveness and attenuated the pro-invasive effect of miR-338-5p mimics. Overall, our results showed that miR-338-5p has a function in promoting glioma cell invasion by targeting TSHZ3 suppression on MMP2. In conclusion, miR-338-5p is a possible potential biomarker for the diagnosis and target for therapy of high-grade glioma.


Assuntos
Regulação Neoplásica da Expressão Gênica/genética , Glioblastoma/genética , Proteínas de Homeodomínio/genética , Metaloproteinase 2 da Matriz/genética , MicroRNAs/genética , Adulto , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética
17.
Int J Mol Sci ; 19(7)2018 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-29966265

RESUMO

Here, we investigated the effects of selenium (Se) applications on two strawberry varieties, Akihime and Benihoppe, under chilling stress and recovery conditions. Changes in photosynthetic parameters, antioxidant enzyme activities, ascorbate (AsA)-glutathione (GSH) cycle-related enzyme activities, and low-molecular-mass antioxidant contents were determined. Foliar spraying with Se alleviated the decline in the net photosynthetic rate and chlorophyll content and increased the malondialdehyde and hydrogen peroxide contents of strawberry seedlings’ leaves under chilling stress. As the time under chilling stress increased, the stomatal conductance decreased and intercellular CO2 concentration increased, suggesting that nonstomatal factors had major limiting effects on the net photosynthetic rate's decrease. Se applications significantly alleviated the adverse impacts of chilling stress on changes in stomatal conductance and intercellular CO2 concentration. Se, especially at lower concentrations, significantly increased superoxide dismutase, catalase, and peroxide enzyme activities during chilling stress. Approximately 5 mg·L−1 of sodium selenite solution had the greatest stress-alleviating effects. Among the AsA-GSH cycle-related enzymes, ascorbate peroxidase, glutathione reductase, dehydroascorbate reductase, and monodehydroascorbate reductase (MDHAR) treatments, coupled with an appropriate dose of Se, significantly enhanced ascorbate peroxidase and MDHAR activities, which suggested that Se applications played important roles in strawberry leaves by affecting AsA-GSH cycle-related defenses against the oxidative damage caused by chilling stress. Furthermore, MDHAR was the key enzyme required to maintain the balance between AsA consumption and regeneration that may assist in protecting strawberry seedlings in a low-temperature environment.


Assuntos
Selênio/farmacologia , Catalase/metabolismo , Temperatura Baixa , Glutationa/metabolismo , NADH NADPH Oxirredutases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Plântula/efeitos dos fármacos , Plântula/metabolismo , Superóxido Dismutase/metabolismo
18.
Molecules ; 23(2)2018 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-29439470

RESUMO

Melatonin is a pleiotropic signal molecule that plays critical roles in regulating plant growth and development, as well as providing physiological protections against various environmental stresses. Nonetheless, the mechanisms for melatonin-mediated pollen thermotolerance remain largely unknown. In this study, we report that irrigation treatment with melatonin (20 µM) effectively ameliorated high temperature-induced inactivation of pollen and inhibition of pollen germination in tomato (Solanum lycopersicum) plants. Melatonin alleviated reactive oxygen species production in tomato anthers under high temperature by the up-regulation of the transcription and activities of several antioxidant enzymes. Transmission electron micrograph results showed that high temperature-induced pollen abortion is associated with a premature degeneration of the tapetum cells and the formation of defective pollen grains with degenerated nuclei at the early uninuclear microspore stage, whilst melatonin protected degradation of organelles by enhancing the expression of heat shock protein genes to refold unfolded proteins and the expression of autophagy-related genes and formation of autophagosomes to degrade denatured proteins. These findings suggest a novel function of melatonin to protect pollen activity under high temperature and support the potential effects of melatonin on reproductive development of plants.


Assuntos
Antioxidantes/farmacologia , Regulação da Expressão Gênica de Plantas , Melatonina/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Pólen/efeitos dos fármacos , Solanum lycopersicum/efeitos dos fármacos , Ascorbato Peroxidases/genética , Ascorbato Peroxidases/metabolismo , Autofagia , Proteínas Relacionadas à Autofagia/agonistas , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Catalase/genética , Catalase/metabolismo , Proteínas de Choque Térmico/agonistas , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico/genética , Temperatura Alta , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Solanum lycopersicum/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Proteínas de Plantas/metabolismo , Pólen/genética , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Desnaturação Proteica , Proteólise , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Termotolerância/efeitos dos fármacos , Termotolerância/genética
19.
Cancer Sci ; 108(8): 1640-1647, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28603915

RESUMO

Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma (NPC). Serum IgA antibodies against early antigen (EA-IgA) and viral capsid antigen (VCA-IgA) are the most commonly used to screen for NPC in endemic areas. However, the prognostic value of serum EA-IgA and VCA-IgA in patients with NPC is less clear. We hypothesize that serum EA-IgA and VCA-IgA levels have prognostic impact for survival outcomes in NPC patients with undetectable pretreatment EBV (pEBV) DNA. In this series, 334 patients with non-metastatic NPC and undetectable pEBV DNA were included. Serum EA-IgA and VCA-IgA were determined by ELISA. After analysis, serum EA-IgA and VCA-IgA loads correlated positively with T, N, and overall stage (all P < 0.05). Serum EA-IgA was not associated with survival outcome in univariable analyses. But patients with serum VCA-IgA >1:120 had significantly inferior 5-year progression-free survival (80.4% vs 89.6%, P = 0.025), distant metastasis-free survival (88.4% vs 94.8%, P = 0.050), and locoregional relapse-free survival (88.4% vs 95.6%, P = 0.023; log-rank test). Multivariable analyses revealed that N stage was the only independent prognostic factor (all P < 0.05), but the VCA-IgA became insignificant. Further analyses revealed that serum VCA-IgA was not an independent prognostic factor in early N (N0-1) or advanced N (N2-3) stage NPC. In summary, although both EA-IgA and VCA-IgA correlate strongly with TNM stage, our analyses do not suggest that these antibodies are prognostic biomarkers in patients with NPC and undetectable pEBV DNA.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Carcinoma/patologia , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/imunologia , Neoplasias Nasofaríngeas/patologia , Adolescente , Adulto , Idoso , Carcinoma/imunologia , Carcinoma/radioterapia , Carcinoma/virologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/radioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/virologia , Estadiamento de Neoplasias , Prognóstico , Análise de Sobrevida , Adulto Jovem
20.
BMC Cancer ; 17(1): 788, 2017 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-29169335

RESUMO

BACKGROUND: To evaluate the incidence of neck muscle spasm in nasopharyngeal carcinoma (NPC) patients that received intensity-modulated radiotherapy (IMRT), and to analyse the patient- and treatment-related risk factors associated with neck muscle spasm. METHODS: A sample of 152 IMRT-treated, biopsy-proven, nondisseminated NPC patients were retrospectively analysed. All had documented IMRT treatment plans and had returned for follow-up review at 4 years post-radiotherapy. Spasm of the sternocleidomastoid (SCM) muscle was graded from 0 to 3 (absent to severe) and this grade served as the clinical endpoint. Risk factors were identified using logistic regression analysis. RESULTS: Within 4 years of radiotherapy, neck muscle spasm developed in 23.68% of the patients; Grades 0, 1, 2 and 3 were respectively assigned to 83.55, 7.57, 6.58 and 2.30% of assessed SCMs. Multivariate analysis indicated that gender, N stage, V60 (percentage of SCM volume that received >60 Gy) were independent prognostic variables, and that the optimal threshold for using V60 to predict neck muscle spasm was 61.92% (sensitivity = 0.900, specificity = 0.953). CONCLUSIONS: Gender, N stage and V60 were independent predictive factors for post-radiotherapy neck muscle spasm, and a V60 of ≤61.92% in the SCM was relatively safe.


Assuntos
Carcinoma/complicações , Carcinoma/epidemiologia , Neoplasias Nasofaríngeas/complicações , Neoplasias Nasofaríngeas/epidemiologia , Músculos do Pescoço/fisiopatologia , Radioterapia de Intensidade Modulada/efeitos adversos , Espasmo/epidemiologia , Espasmo/etiologia , Adulto , Carcinoma/diagnóstico , Carcinoma/radioterapia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/radioterapia , Estadiamento de Neoplasias , Curva ROC , Dosagem Radioterapêutica , Fatores de Risco , Espasmo/diagnóstico , Adulto Jovem
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