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1.
Plant Cell ; 35(4): 1167-1185, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36530163

RESUMO

Carotenoids are natural pigments that influence the color of citrus fruit. The red-colored carotenoid ß-citraurin is responsible for the peel color in "Newhall" orange (Citrus sinensis). Although jasmonates are known to regulate the biosynthesis and accumulation of carotenoids, their effects on ß-citraurin biosynthesis in citrus fruit remain unclear. Here, we determined that treatment with methyl jasmonate (MeJA) significantly promotes fruit coloration and ß-citraurin production in "Newhall" orange. A MeJA treatment induced the expression of CsMYC2, which encodes a transcription factor that serves as a master regulator of jasmonate responses. CsMYC2 bound the promoter of the gene that encodes carotenoid cleavage dioxygenase 4b (CsCCD4b), the key gene for ß-citraurin biosynthesis, and the promoters of genes that encode phytoene synthase (CsPSY), lycopene ß-cyclase (CsLCYb), and ß-carotene hydroxylase (CsBCH) and induced their expression. In addition, CsMYC2 promoted CsMPK6 expression. Notably, we found that CsMPK6 interacted with CsMYC2 and that this interaction decreased the stability and DNA-binding activity of CsMYC2. Thus, we conclude that negative feedback regulation attenuates JA signaling during the jasmonate-induced coloration of citrus fruit. Together, our findings indicate that jasmonates induce ß-citraurin biosynthesis in citrus by activating a CsMPK6-CsMYC2 cascade, thereby affecting fruit coloration.


Assuntos
Citrus sinensis , Citrus , Carotenoides/metabolismo , Citrus/genética , Citrus/metabolismo , Citrus sinensis/genética , Citrus sinensis/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Geranil-Geranildifosfato Geranil-Geraniltransferase
2.
Small ; : e2310409, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38477694

RESUMO

Electrochemical nitrite reduction reaction ( NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^{\mathrm{ - }}{\mathrm{RR}}$ ), as a green and sustainable ammonia synthesis technology, has broad application prospects and environmental friendliness. Herein, an unconventional p-d orbital hybridization strategy is reported to realize the fabrication of defect-rich CuSb porous nanonetwork (CuSb PNs) electrocatalyst for NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^ - {\mathrm{RR}}$ . The crystalline/amorphous heterophase structure is cleverly introduced into the porous nanonetworks, and this defect-rich structure exposes more atoms and activated boundaries. CuSb PNs exhibit a large NH3 yield ( r N H 3 ${{r}_{{\mathrm{N}}{{{\mathrm{H}}}_{\mathrm{3}}}}}$ ) of 946.1 µg h-1 m cat - 1 ${\mathrm{m}}_{{\mathrm{cat}}}^{ - {\mathrm{1}}}$ and a high faradaic efficiency (FE) of 90.7%. Experimental and theoretical studies indicate that the excellent performance of CuSb PNs results from the defect-rich porous nanonetworks structure and the p-d hybridization of Cu and Sb elements. This work describes a powerful pathway for the fabrication of p-d orbital hybrid defect-rich porous nanonetworks catalysts, and provides hope for solving the problem of nitrogen oxide pollution in the field of environment and energy.

3.
Plant Biotechnol J ; 22(3): 722-737, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37915111

RESUMO

Carotenoids contribute to fruit coloration and are valuable sources of provitamin A in the human diet. Abscisic acid (ABA) plays an essential role in fruit coloration during citrus fruit ripening, but little is known about the underlying mechanisms. Here, we identified a novel bZIP transcription activator called CsbZIP44, which serves as a central regulator of ABA-mediated citrus carotenoid biosynthesis. CsbZIP44 directly binds to the promoters of four carotenoid metabolism-related genes (CsDXR, CsGGPPs, CsBCH1 and CsNCED2) and activates their expression. Furthermore, our research indicates that CsHB5, a positive regulator of ABA and carotenoid-driven processes, activates the expression of CsbZIP44 by binding to its promoter. Additionally, CsHB5 interacts with CsbZIP44 to form a transcriptional regulatory module CsHB5-CsbZIP44, which is responsive to ABA induction and promotes carotenoid accumulation in citrus. Interestingly, we also discover a positive feedback regulation loop between the ABA signal and carotenoid biosynthesis mediated by the CsHB5-CsbZIP44 transcriptional regulatory module. Our findings show that CsHB5-CsbZIP44 precisely modulates ABA signal-mediated carotenoid metabolism, providing an effective strategy for quality improvement of citrus fruit and other crops.


Assuntos
Ácido Abscísico , Citrus , Humanos , Ácido Abscísico/metabolismo , Citrus/genética , Regulação da Expressão Gênica de Plantas/genética , Carotenoides/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Frutas/genética , Frutas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
4.
J Craniofac Surg ; 34(2): e164-e167, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36227780

RESUMO

BACKGROUND: Eye bags especially give an impression of aging and mental exhaustion. At present, the surgical methods of bags mainly include conjunctival approach and lower eyelid skin approach. With the continuous upgrading of the concept of facial esthetics, the lower eyelid pouch surgery for middle-aged and elderly patients pays more attention to reducing surgical trauma, improving tear trough deformity along with the effacement of lid­cheek junction. OBJECTIVE: This paper discusses the clinical effect of the lower lid blepharoplasty involved orbital septum fat repositioning based on oral fixation via conjunctival approach combined with relaxation skin resection in the treatment of eye bags in elderly patient. METHODS: Fifty elderly patients underwent blepharoplasty between January of 2021 and June of 2021 at our hospital. The lower eyelid orbital septum fat was released along with the prezygomatic space and the premaxillary space were stripped through the conjunctival approach. The released cellulite was redistributed in the prezygomatic space/premaxillary space and fixed in the oral vestibular with 5-0 Polysorb through the middle facial tunnel. Finally, the appropriate skin was finally removed. RESULTS: After operation, 48 patients were satisfied with the operation results, with tight lower eyelid skin and natural lid­cheek junction. One patient with conjunctival infection was cured after 7 days of antibiotic eye drops. One patient felt foreign body when chewing, and the symptoms disappeared naturally after 5 days without treatment. CONCLUSION: For middle-aged and elderly patients with bags, the surgical method in this study not only has good postoperative effect, but also has small damage to the lower eyelid orbicularis muscle. The appearance is natural and the lower eyelid skin is tight. The effacement of lid­cheek junction and recreating a smooth transition of lower lid cheek interface, which can correct lacrimal groove deformity. The patients have high acceptance and satisfaction, which can be widely used in clinical practice.


Assuntos
Blefaroplastia , Pálpebras , Pessoa de Meia-Idade , Idoso , Humanos , Pálpebras/cirurgia , Blefaroplastia/métodos , Túnica Conjuntiva/cirurgia , Músculos Oculomotores/cirurgia , Órbita/cirurgia , Tecido Adiposo/transplante
5.
J Sci Food Agric ; 102(7): 2731-2740, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34709652

RESUMO

BACKGROUND: Heat-induced composite gels were prepared with 20 g kg-1 myofibrillar protein (MP) sol, 20 g kg-1 modified starch and 100 g kg-1 lipid pre-emulsified by MP in 0.6 mol L-1 NaCl, at pH 6.2. The effects of esterified potato starch (EPS) and emulsified lipid (lard or peanut oil) on the rheology, texture properties and nuclear magnetic resonance characterization of MP gel were evaluated. RESULTS: The addition of starch and lipid significantly improved the gel strength and water holding capacity (WHC) of the MP gel. Analysis of the relaxation time compared with the WHC tests showed that the variation range of the transverse T22 relaxation time of a gel was positively proportional to changes in WHC of the composite gel, and the lower the T22 relaxation time, the better the WHC of composite gel. Moreover, MP gel with starch and emulsified lard added at the same time has the lowest T2 relaxation time, and also the best WHC of the gel. Environmental scanning electron microscopy showed that emulsified oil droplets embedded the gaps in the protein network, and the gelatinized starch contributed to restrict the oil droplet size, resulting in thicker MP gel. CONCLUSION: Emulsified lipid and modified starch have an important influence on the rheology and microstructure of MP gels, indicating the subtle interaction between starch, lipid and protein. The results suggest the potential feasibility of modified starch and vegetable oil to improve the textural properties in comminuted meat products. © 2021 Society of Chemical Industry.


Assuntos
Solanum tuberosum , Gorduras na Dieta , Géis/química , Proteínas Musculares/química , Óleo de Amendoim , Reologia , Amido/química , Água
6.
Plant Sci ; 346: 112131, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38801863

RESUMO

Uneven coloration is a common phenomenon in citrus fruit during the ripening stage, as affects the appearance and economic value of the fruit. The elevated expression of CsERF003 during the degreening process of both lemon and satsuma mandarin peels was reported. In this research, a similar performance of CsERF003 in the pericarp coloration process was also identified by transcriptome analysis of 'Fengjie 72-1' navel orange and Lane Late navel orange. However, the regulatory mechanism of CsERF003 is not clear yet. Overexpression of CsERF003 could deepen the color of citrus callus and promote peel degreening of Newhall navel orange, which was attributed to the upregulation of genes involved in chlorophyll degradation and carotenoid synthesis. Furthermore, CsERF003 acted as an activator to promote the expression of CsLCYE, but couldn't activate the expression of CsLCYB1 and CsLCYB2; CsERF003 could also bind to the promoter of CsSGR to activate its expression. Together, our findings shed light on the regulatory mechanism of CsERF003 in chlorophyll degradation and carotenoid accumulation, particularly in the α-branch of carotenoid metabolism. These insights offer valuable perspectives for the genetic enhancement of peel coloration in citrus.


Assuntos
Carotenoides , Clorofila , Citrus , Frutas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Clorofila/metabolismo , Carotenoides/metabolismo , Frutas/metabolismo , Frutas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Citrus/metabolismo , Citrus/genética , Pigmentação/genética
7.
Transl Stroke Res ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748378

RESUMO

Intracerebral hemorrhage (ICH) imposes a significant burden on patients, and the volume of hematoma plays a crucial role in determining the severity and prognosis of ICH. Although significant recent progress has been made in understanding the cellular and molecular mechanisms of surrounding brain tissue in ICH, our current knowledge regarding the precise impact of hematoma volumes on neural circuit damage remains limited. Here, using a viral tracing technique in a mouse model of striatum ICH, two distinct patterns of injury response were observed in upstream connectivity, characterized by both linear and nonlinear trends in specific brain areas. Notably, even low-volume hematomas had a substantial impact on downstream connectivity. Neurons in the striatum-ICH region exhibited heightened excitability, evidenced by electrophysiological measurements and changes in metabolic markers. Furthermore, a strong linear relationship (R2 = 0.91) was observed between hematoma volumes and NFL damage, suggesting a novel biochemical index for evaluating changes in neural injury. RNA sequencing analysis revealed the activation of the MAPK signaling pathway following hematoma, and the addition of MAPK inhibitor revealed a decrease in neuronal circuit damage, leading to alleviation of motor dysfunction in mice. Taken together, our study highlights the crucial role of hematoma size as a determinant of circuit injury in ICH. These findings have important implications for clinical evaluations and treatment strategies, offering opportunities for precise therapeutic approaches to mitigate the detrimental effects of ICH and improve patient outcomes.

8.
J Colloid Interface Sci ; 667: 175-183, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636219

RESUMO

Compared with layered materials such as graphite and transition metal disulfide compounds with highly anisotropic in-plane covalent bonds, it is inherently more challenging to obtain independent metallic two-dimensional films with atomic thickness. In this study, PtNi layered metallene nanobowls (LMBs) with multilayer atomic-scale nanosheets and bowl-like structures have been synthesized in one step using structural and electronic effects. The material has the advantage of catalyzing pH-universal hydrogen evolution reaction (HER). Compared with Pt/C, PtNi LMBs exhibited excellent HER activity and stability under all pH conditions. The overpotentials of 10 mA cm-2 at 0.5 M H2SO4, 1.0 M phosphate buffer and 1.0 M KOH were 14.8, 20.3, and 34.0 mV, respectively. Under acidic, neutral and alkaline conditions, the HER Faraday efficiencies reach 98.97%, 98.85%, and 99.04%, respectively. This study provides an example for the preparation of unique multilayer nanobowls, and also provides a basic research platform for the development of special HER materials.

9.
Ultrason Sonochem ; 94: 106349, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36870098

RESUMO

Effects of the incorporation of ultrasound with varied intensities (0-800 W) into the thermal-induced gelation process on the gelling properties of myofibrillar protein (MP) were explored. In comparison with single heating, ultrasound-assisted heating (<600 W) led to significant increases in gel strength (up to 17.9%) and water holding capacity (up to 32.7%). Moreover, moderate ultrasound treatment was conducive to the fabrication of compact and homogenous gel networks with small pores, which could effectively impair the fluidity of water and allow redundant water to be entrapped within the gel network. Electrophoresis revealed that the incorporation of ultrasound into the gelation process facilitated more proteins to get involved in the development of gel network. With the intensified ultrasound power, α-helix in the gels lowered pronouncedly with a simultaneous increment of ß-sheet, ß-turn, and random coil. Furthermore, hydrophobic interactions and disulfide bonds were reinforced by the ultrasound treatment, which was in support of the construction of preeminent MP gels.


Assuntos
Proteínas Musculares , Miofibrilas , Proteínas Musculares/química , Interações Hidrofóbicas e Hidrofílicas , Géis/química , Miofibrilas/química , Água/química
10.
Hortic Res ; 10(11): uhad199, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38023480

RESUMO

Carotenoids directly influence citrus fruit color and nutritional value, which is critical to consumer acceptance. Elucidating the potential molecular mechanism underlying carotenoid metabolism is of great importance for improving fruit quality. Despite the well-established carotenoid biosynthetic pathways, the molecular regulatory mechanism underlying carotenoid metabolism remains poorly understood. Our previous studies have reported that the Myc-type basic helix-loop-helix (bHLH) transcription factor (TF) regulates citrus proanthocyanidin biosynthesis. Transgenic analyses further showed that overexpression of CsTT8 could significantly promote carotenoid accumulation in transgenic citrus calli, but its regulatory mechanism is still unclear. In the present study, we found that overexpression of CsTT8 enhances carotenoid content in citrus fruit and calli by increasing the expression of CsDXR, CsHDS, CsHDR, CsPDS, CsLCYE, CsZEP, and CsNCED2, which was accompanied by changes in the contents of abscisic acid and gibberellin. The in vitro and in vivo assays indicated that CsTT8 directly bound to the promoters of CsDXR, CsHDS, and CsHDR, the key metabolic enzymes of the methylerythritol 4-phosphate (MEP) pathway, thus providing precursors for carotenoid biosynthesis and transcriptionally activating the expression of these three genes. In addition, CsTT8 activated the promoters of four key carotenoid biosynthesis pathway genes, CsPDS, CsLCYE, CsZEP, and CsNCED2, directly promoting carotenoid biosynthesis. This study reveals a novel network of carotenoid metabolism regulated by CsTT8. Our findings will contribute to manipulating carotenoid metabolic engineering to improve the quality of citrus fruit and other crops.

11.
RSC Adv ; 12(37): 24014-24025, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36093231

RESUMO

Fe-based oxygen carriers (OCs) are widely used in chemical looping steam reforming (CLSR) due to excellent resistance to carbon buildup, low toxicity, and high activity. In this study, a type of nano NiO-Fe2O3/Al2O3 Fe-based OC that can easily be reduced by fuels and re-oxidized by air was developed for use in glycerol CLSR. It was synthesized by co-precipitation and impregnation. Based on the quadratic regression orthogonal model, a quadratic polynomial function was established to investigate the effects of temperature (T), water/carbon ratio (S/C), and loading (M) on hydrogen content (HL) and hydrogen selectivity (S). The OCs were characterized by XRD, XPS, SEM/EDX-mapping, TEM, and H2-TPR to determine their physicochemical properties. XPS shows the Fe phase highly interacted with the Al2O3 supporting matrix by forming Fe aluminates in NiO-Fe2O3/Al2O3. The S (85.33%) and HL (78.41%) were obtained under the optimal conditions T = 600 °C, S/C = 1.0 mol mol-1 and M = 0. A hydrogen content fluctuation within 4% was obtained under T = 700 °C, S/C = 1.0 mol mol-1, and M = 2.5%, which means the cycle stability is perfect because of the addition of Ni. This study provides a basis for the development of efficient oxygen carriers in the CLSR system.

12.
Foods ; 10(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34945628

RESUMO

To investigate the role of sulfhydryl groups and disulfide bonds in different protein-stabilized emulsions, N-ethylmaleimide (NEM) was used as a sulfhydryl-blocking agent added in the emulsion. The addition of NEM to block the sulfhydryl groups resulted in a reduction in disulfide bond formation, which enabled the internal structure of the protein molecule to be destroyed, and then decreased the restriction of protein membrane on the oil droplets. Furthermore, with the NEM content increasing in the emulsion, a reduction in the protein emulsifying activity and emulsion stability also occurred. At the same time, the intermolecular interaction of the protein on the oil droplet interface membrane was destroyed, and the emulsion droplet size increased with the NEM content in the emulsion. Although NEM blocking sulfhydryl groups from forming disulfide bonds has similar effects on three types of protein emulsion, the degree of myofibrillar protein (MP), egg-white protein isolate (EPI), and soybean protein isolate (SPI) used as emulsifiers had a subtle difference.

13.
Biosens Bioelectron ; 57: 139-42, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24583318

RESUMO

This paper describes an investigation of a facile colorimetric sensor for Hg(2+) in aqueous solution based on the anti-aggregation of silver nanoparticles (AgNPs). In the absence of Hg(2+), the addition of 6-Thioguanine to AgNPs solution led to the aggregation of AgNPs, resulting in a color change from yellow to brown with a red shift of absorption spectra. However, the presence of Hg(2+) inhibited the 6-Thioguanine-induced aggregation of AgNPs accompanying with a color change from brown to yellow. Under the optimal conditions, the ratio between the absorbance at 530 nm and 394 nm (A530/A394) was linearly proportional to the Hg(2+) concentration in a range from 0 to 333 nM with a detection limit of 4 nM. Other environmentally relevant metal ions did not interfere with the detection of Hg(2+). The proposed method was simple, cost-effective and rapid without any complicated modifying step. It was successfully applied to detect Hg(2+) in environmental water samples.


Assuntos
Colorimetria/métodos , Mercúrio/análise , Nanopartículas/química , Prata/química , Poluentes Químicos da Água/análise , Cátions Bivalentes/análise , Limite de Detecção , Tioguanina/química
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