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1.
Mol Ther ; 32(5): 1387-1406, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38414247

RESUMO

Cisplatin-induced hearing loss is a common side effect of cancer chemotherapy in clinics; however, the mechanism of cisplatin-induced ototoxicity is still not completely clarified. Cisplatin-induced ototoxicity is mainly associated with the production of reactive oxygen species, activation of apoptosis, and accumulation of intracellular lipid peroxidation, which also is involved in ferroptosis induction. In this study, the expression of TfR1, a ferroptosis biomarker, was upregulated in the outer hair cells of cisplatin-treated mice. Moreover, several key ferroptosis regulator genes were altered in cisplatin-damaged cochlear explants based on RNA sequencing, implying the induction of ferroptosis. Ferroptosis-related Gpx4 and Fsp1 knockout mice were established to investigate the specific mechanisms associated with ferroptosis in cochleae. Severe outer hair cell loss and progressive damage of synapses in inner hair cells were observed in Atoh1-Gpx4-/- mice. However, Fsp1-/- mice showed no significant hearing phenotype, demonstrating that Gpx4, but not Fsp1, may play an important role in the functional maintenance of HCs. Moreover, findings showed that FDA-approved luteolin could specifically inhibit ferroptosis and alleviate cisplatin-induced ototoxicity through decreased expression of transferrin and intracellular concentration of ferrous ions. This study indicated that ferroptosis inhibition through the reduction of intracellular ferrous ions might be a potential strategy to prevent cisplatin-induced hearing loss.


Assuntos
Cisplatino , Ferroptose , Perda Auditiva , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Animais , Cisplatino/efeitos adversos , Ferroptose/efeitos dos fármacos , Ferroptose/genética , Camundongos , Perda Auditiva/induzido quimicamente , Perda Auditiva/genética , Perda Auditiva/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Modelos Animais de Doenças , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Espécies Reativas de Oxigênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Células Ciliadas Auditivas Externas/metabolismo , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Células Ciliadas Auditivas Externas/patologia , Ototoxicidade/etiologia , Ototoxicidade/metabolismo , Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos
2.
Sensors (Basel) ; 24(5)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38475200

RESUMO

Casting defects in turbine blades can significantly reduce an aero-engine's service life and cause secondary damage to the blades when exposed to harsh environments. Therefore, casting defect detection plays a crucial role in enhancing aircraft performance. Existing defect detection methods face challenges in effectively detecting multi-scale defects and handling imbalanced datasets, leading to unsatisfactory defect detection results. In this work, a novel blade defect detection method is proposed. This method is based on a detection transformer with a multi-scale fusion attention mechanism, considering comprehensive features. Firstly, a novel joint data augmentation (JDA) method is constructed to alleviate the imbalanced dataset issue by effectively increasing the number of sample data. Then, an attention-based channel-adaptive weighting (ACAW) feature enhancement module is established to fully apply complementary information among different feature channels, and further refine feature representations. Consequently, a multi-scale feature fusion (MFF) module is proposed to integrate high-dimensional semantic information and low-level representation features, enhancing multi-scale defect detection precision. Moreover, R-Focal loss is developed in an MFF attention-based DEtection TRansformer (DETR) to further solve the issue of imbalanced datasets and accelerate model convergence using the random hyper-parameters search strategy. An aero-engine turbine blade defect X-ray (ATBDX) image dataset is applied to validate the proposed method. The comparative results demonstrate that this proposed method can effectively integrate multi-scale image features and enhance multi-scale defect detection precision.

3.
Planta ; 258(2): 24, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37344696

RESUMO

MAIN CONCLUSION: OsFAR1 encodes a fatty acyl-CoA reductase involved in biosynthesis of primary alcohols and plays an important role in drought stress response in rice. Cuticular waxes cover the outermost surface of terrestrial plants and contribute to inhibiting nonstomatal water loss and improving plant drought resistance. Primary alcohols are the most abundant components in the leaf cuticular waxes of rice (Oryza sativa), but the biosynthesis and regulation of primary alcohol remain largely unknown in rice. Here, we identified and characterized an OsFAR1 gene belonging to the fatty acyl-CoA reductases (FARs) via a homology-based approach in rice. OsFAR1 was activated by abiotic stresses and abscisic acid, resulting in increased production of primary alcohol in rice. Heterologous expression of OsFAR1 enhanced the amounts of C22:0 and C24:0 primary alcohols in yeast (Saccharomyces cerevisiae) and C24:0 to C32:0 primary alcohols in Arabidopsis. Similarly, OsFAR1 overexpression significantly increased the content of C24:0 to C30:0 primary alcohols on rice leaves. Finally, OsFAR1 overexpression lines exhibited reduced cuticle permeability and enhanced drought tolerance in rice and Arabidopsis. Taken together, our results demonstrate that OsFAR1 is involved in rice primary alcohol biosynthesis and plays an important role in responding to drought and other environmental stresses.


Assuntos
Arabidopsis , Oryza , Oryza/genética , Oryza/metabolismo , Resistência à Seca , Arabidopsis/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Álcoois/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Secas , Álcoois Graxos/metabolismo , Ceras/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas/metabolismo
4.
Mikrochim Acta ; 190(1): 12, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36478524

RESUMO

R-CDAs have been synthesized in a one-pot solvothermal procedure starting from 3,4-diaminobenzoic acid in an acidic medium. Transmission electron microscopy (TEM) revealed that R-CDAs nanoparticles exhibited a much larger diameter of 7.2-28.8 nm than traditional monodisperse carbon dots. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) revealed the presence of polar functional groups (hydroxyl, amino, carboxyl) on the surface of R-CDAs. Upon excitation with visible light (550 nm), R-CDAs emit stable, red fluorescence with a maximum at 610 nm. Under the optimum conditions, Cu2+ ions quench the fluorescence of this probe, and the signal is linear in a concentration range of copper ions between 5 and 600 nM with the detection limit of only 0.4 nM. Recoveries from 98.0 to 105.0% and relative standard deviations (RSD) from 2.8 to 4.5% have been obtained for detection of Cu2+ in real water samples. Furthermore, the R-CDAs fluorescent probe showed negligible cytotoxicity toward HeLa cells and good bioimaging ability, suggesting its potential applicability as a diagnostic tool in biomedicine.


Assuntos
Carbono , Corantes Fluorescentes , Humanos , Corantes Fluorescentes/toxicidade , Carbono/toxicidade , Células HeLa , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Environ Manage ; 318: 115476, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35714471

RESUMO

Although it is well acknowledged that the improvement of ecosystem services is conducive to human well-being, there is still a lack of approach to determining reasonable improvement goals, especially for ecosystem services with trade-off relationship. Based on the method of production possibility frontier (PPF), this study presented a novel approach to identifying the improvement goals of interacting ecosystem services with considering their context dependency. By calculating the gap between the current supply of ecosystem services and the reasonable improvement goal, the ecosystem services supply efficiency was defined and measured to identify the optimization potentials of ecosystem services with trade-off relationship. The results showed that the supply efficiency of ecosystem services (grain production and water purification) decreased and then increased significantly along with the increasing of farmland area ratio in the Dongting Lake Basin (DLB). Meanwhile, the inflection point appeared when the farmland area ratio was 0.16. The change of farmland area ratio was significantly influenced by the change of elevation, with the regression coefficients of elevation on the left and right sides of the inflection point being -1.28 and -0.5 respectively, which were higher than that of other factors. Along with the increasing of elevation, the ecosystem services supply efficiency decreased but increased when the elevation exceeded 721.74 m. Furthermore, the sub-watersheds with farmland area ratio below the inflection point, i.e. mainly high elevation areas, were located around national or provincial level poor counties, posing a great challenge for improving ecosystem services with trade-off relationship. Development strategies for sub-watersheds should consider the non-linear trade-offs of ecosystem services, especially the opposite stages of supply efficiency. This study highlighted the elevation dependency of ecosystem services supply efficiency through farmland area ratio in great lake watershed.


Assuntos
Ecossistema , Lagos , China , Conservação dos Recursos Naturais , Humanos
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(5): 858-868, 2021 Oct 25.
Artigo em Zh | MEDLINE | ID: mdl-34713653

RESUMO

To solve the problem of stent malapposition of intravascular stents, explore the design method of intravascular body-fitted stent structure and to establish an objective apposition evaluation method, the support and apposition performance of body-fitted stent in the stenotic vessels with different degrees of calcified plaque were simulated and analyzed. The traditional tube-mesh-like stent model was constructed by using computational aided design tool SolidWorks, and based on this model, the body-fitted stent model was designed by means of projection algorithm. Abaqus was used to simulate the crimping-expansion-recoil process of the two stents in the stenotic vessel with incompletely calcified plaque and completely calcified plaque respectively. A comprehensive method for apposition evaluation was proposed considering three aspects such as separation distance, fraction of non-contact area and residual volume. Compared with the traditional stent, the separation distances of the body-fitted stent in the incompletely calcified plaque model and the completely calcified plaque model were decreased by 21.5% and 22.0% respectively, the fractions of non-contact areas were decreased by 11.3% and 11.1% respectively, and the residual volumes were decreased by 93.1% and 92.5% respectively. The body-fitted stent improved the apposition performance and was effective in both incompletely and completely calcified plaque models. The established apposition performance evaluation method of stent considered more geometric factors, and the results were more comprehensive and objective.


Assuntos
Placa Aterosclerótica , Stents , Constrição Patológica/cirurgia , Humanos
7.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(6): 956-966, 2020 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-33369334

RESUMO

The dynamic coupling of stent degradation and vessel remodeling can influence not only the structural morphology and material property of stent and vessel, but also the development of in-stent restenosis. The research achievements of biomechanical modelling and analysis of stent degradation and vessel remodeling were reviewed; several noteworthy research perspectives were addressed, a stent-vessel coupling model was developed based on stent damage function and vessel growth function, and then concepts of matching ratio and risk factor were established so as to evaluate the treatment effect of stent intervention, which may lay the scientific foundation for the structure design, mechanical analysis and clinical application of biodegradable stent.


Assuntos
Stents , Fenômenos Biomecânicos , Constrição Patológica , Humanos
8.
Photochem Photobiol Sci ; 18(7): 1638-1648, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31090779

RESUMO

We developed a type of dye-doped cholesteric liquid crystal, which were used for fluorescence enhancement and dual-mode multicolor patterns. We added dye molecules (BBOT, coumarin 6 (C6) and rhodamine B (RhB)) to liquid crystals, and cholesteric liquid crystals (CLC) exhibited selective reflection characteristics. When the reflection wavelength overlaps with the peak of the fluorescent dye, the luminescence intensity of the dye molecules could be adjusted. We used two methods to adjust the reflection wavelength of the cholesteric liquid crystals by changing the content of chiral additives and the isomerization degree of azo molecules. We used the screen printing and stencil printing methods to combine liquid crystal particles containing different fluorescent colors to prepare multicolor patterns. Moreover, the photoisomerization characteristics of the azo molecules were also used to achieve brilliant firework-like images upon exposure to ultraviolet and visible light. In addition, we also realized a face-changing stunt with facial makeup during a performance in the Sichuan Opera, a traditional Chinese folk art. We made use of the difference between reflection color and luminescence intensity upon light irradiation to present orange, green, blue and dark-blue facial effects.

9.
Nanotechnology ; 30(50): 505706, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31491778

RESUMO

In this study, we designed the luminescent enhanced composites by combining upconversion nanoparticles (UCNPs) and photonic crystals (PCs), and prepared multi-mode coding patterns through utilizing the optical properties of both materials, respectively. We prepared UCNPs with different luminescence and the composite materials can be quickly obtained by spin-coating the UCNPs on the surface of the PCs. We discover that the composite materials have significant luminescent enhancement and the enhancement of upconversion is attributed to the Bragg reflection of the photonic band gap. We fabricated upconversion luminescent lattices based on the surface of the PCs by dropping and endowed with the meaning of the Morse code so that it can have more information in different modes. In addition, we further obtained the cipher table pattern according to the structural color of the PCs and the luminescence of the UCNPs. The results reveal great potential applications in the field of multi-mode optical imaging and anti-counterfeiting.

10.
Am J Otolaryngol ; 40(2): 183-186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30551897

RESUMO

PURPOSE: The timing of CI for postmeningitic deafness is controversial and differential outcomes have been reported. To review and share our surgical and auditory outcomes. MATERIALS AND METHODS: 17 patients with ossified cochleas who received CI were enrolled. Clinical data including the cause of cochlear ossification, preoperative examination, onset of deafness, age at implantation, surgical findings, and relevant auditory outcomes was analysed. RESULTS: Cochlear ossification was observed in 53% of patients with HRCT, whereas the corresponding value for MRI was 59%. Patients in both stage I and II received complete insertion of the electrode array, however, stage III patients only received partial insertion. 1 patient in stage II received bilateral CI. Hearing tests showed increased average hearing threshold for stage III patients than those in stage I and II (P < 0.05). CAP scores were much lower for stage III patients than those in stage I and II (P < 0.05). Postlingual deafness patients showed higher SIR scores than prelingual deafness children (P < 0.05). CONCLUSIONS: HRCT and MRI have comparable value in predicting the occurrence of ossification in cochleas. We recommend fast surgical intervention in the patients with bilateral profound postmeningitic deafness. If possible, bilateral cochlear implantation is recommended.


Assuntos
Cóclea/patologia , Cóclea/cirurgia , Doenças Cocleares/cirurgia , Implante Coclear/métodos , Ossificação Heterotópica/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Cóclea/diagnóstico por imagem , Doenças Cocleares/diagnóstico por imagem , Doenças Cocleares/reabilitação , Imagem de Difusão por Ressonância Magnética , Feminino , Seguimentos , Humanos , Imageamento Tridimensional , Lactente , Masculino , Pessoa de Meia-Idade , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/reabilitação , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
11.
Macromol Rapid Commun ; 39(20): e1800134, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29806723

RESUMO

Light and electrothermal responsive polymer photonic crystals (PCs) modified with 1'-acryloyl chloride-3',3'-dimethyl-6-nitro-spiro(2H-1-benzopyran-2,2'-indoline) (SPMA) are proposed, and their dynamic display patterns are achieved through the combination of the SPMA-modified PCs and a patterned graphite layer. These PCs exhibit fluorescence under UV light irradiation because of the isomerization of the SPMA, which is restricted in the shell of the polymer colloidal spheres. After a voltage is applied to the patterned graphite layer, the fluorescence of PCs in the specific area disappears, and dynamic display patterns are obtained. Under UV light irradiation, the PCs change from the "partial-fluorescence" state to the initial "fluorescence" state, and the patterns disappear. Using this technique, the PC pattern "M L N" on the glass substrate and PC patterns from "0" to "9" on the paper substrate are fabricated. Thus, these dual-responsive PCs have potential applications in information recording, anticounterfeiting, dynamic display, and photoelectric devices.


Assuntos
Benzopiranos/química , Indóis/química , Polímeros/química , Benzopiranos/síntese química , Cristalização , Indóis/síntese química , Fótons , Polímeros/síntese química , Polímeros/efeitos da radiação , Raios Ultravioleta
12.
Biomater Adv ; 156: 213693, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37992478

RESUMO

Biodegradable stents can support vessels for an extended period, maintain vascular patency, and progressively degrade once vascular remodeling is completed, thereby reducing the constraints of traditional metal stents. An ideal degradable stent must have good mechanical properties, degradation behavior, and biocompatibility. Zinc has become a new type of biodegradable metal after magnesium and iron, owing to its suitable degradation rate and good biocompatibility. However, zinc's poor strength and ductility make it unsuitable as a vascular stent material. Therefore, this paper reviewed the primary methods for improving the overall properties of zinc. By discussing the mechanical properties, degradation behavior, and biocompatibility of various improvement strategies, we found that alloying is the most common, simple, and effective method to improve mechanical properties. Deformation processing can further improve the mechanical properties by changing the microstructures of zinc alloys. Surface modification is an important means to improve the biological activity, blood compatibility and corrosion resistance of zinc alloys. Meanwhile, structural design can not only improve the mechanical properties of the vascular stents, but also endow the stents with special properties such as negative Poisson 's ratio. Manufacturing zinc alloys with excellent degradation properties, improved mechanical properties and strong biocompatibility and exploring their mechanism of interaction with the human body remain areas for future research.


Assuntos
Materiais Biocompatíveis , Zinco , Humanos , Materiais Biocompatíveis/uso terapêutico , Implantes Absorvíveis , Ligas , Stents , Magnésio/farmacologia , Magnésio/uso terapêutico
13.
Plants (Basel) ; 13(10)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38794355

RESUMO

To enhance the understanding of yield-related traits in tetraploid wheat, it is crucial to investigate and identify genes that govern superior yield characteristics. This study utilized the wheat55K single nucleotide polymorphism array to genotype a recombinant inbred line (RIL) population consisting of 120 lines developed through the crossbreeding of two tetraploid wheat varieties, Qin Hei-1 (QH-1) and Durum Wheat (DW). An investigation and analysis were conducted on 11 yield-related traits, including peduncle length (PL), neck length (NL), spike length (SL), flowering date (FD), heading date (HD), thousand-kernel weight (TKW), kernel area ratio (KAR), kernel circumference (KC), kernel length (KL), kernel width (KW), and kernel length-width ratio (KL-WR), over a period of three years in two locations, Yang Ling, Shaanxi, and Lin He, Inner Mongolia. The analysis identified nine stable loci among eight agronomic traits, named QSL.QD-1A.1, QNL.QD-4B.2, QPL.QD-4B.1, QFD.QD-2B, QHD.QD-2B.1, QHD.QD-4B, QKC.QD-4B.2, QKL-WR.QD-4B.6, and QKL.QD-4B.2. Among them, the additive effects of three QTLs, QSL.QD-1A.1, QNL.QD-4B.2, and QFD.QD-2B, were positive, indicating that the enhancing alleles at these loci were derived from the parent line QH-1. These three QTLs showed significant positive effects on the phenotypes of the population materials. Furthermore, potential functional genes were identified within the mapping intervals of QSL.QD-1A.1 and QNL.QD-4B.2, which regulate the development of spike length and neck length, respectively. These results provide potential QTLs and candidate genes, which broaden the genetic basis of agronomic traits related to yield, such as SL, NL, PL, and FD, and benefits for wheat breeding and improvement.

14.
Anim Biosci ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38754842

RESUMO

Objective: This study investigated the efficacy of different concentrations of Cholesterol-loaded cyclodextrin (CLC) on cryopreservation in boar sperm quality. Methods: In this study, we treated boar sperm with different concentrations of CLC before freezing and analyzed the sperm cholesterol concentration, plasma membrane, acrosome integrity rate and total motility rate before and after freeze-thawing. We also investigated the levels of reactive oxygen species (ROS), malondialdehyde (MDA), ATP, and structural- and oxidative-damage related proteins in all groups after thawing. Results: The results revealed that the cholesterol concentration of the CLC-treated groups was higher than that of the control group, both before freezing and after thawing (p < 0.05). The plasma membrane integrity rate, acrosome integrity rate, and total motility rate of sperm were also enhanced after thawing in the CLC-treated group (all p < 0.05). Moreover, ROS and MDA production and ATP loss were reduced in CLC-treated sperm during freezing and thawing (p < 0.05). Finally, CLC pretreatment partially prevented the consumption of various proteins involved in metabolism including CAPZB, HSP90AA1 and PGAM2 (p < 0.05). Conclusion: CLC treatment increased cholesterol concentration and decreased structural injury and oxidative damage during boar sperm freezing and thawing, improving the efficacy of sperm cryopreservation in boar.

15.
Antioxidants (Basel) ; 13(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38397846

RESUMO

Postovulatory aging is known to impair the oocyte quality and embryo development due to oxidative stress in many different animal models, which reduces the success rate or pregnancy rate in human assisted reproductive technology (ART) and livestock timed artificial insemination (TAI), respectively. Salidroside (SAL), a phenylpropanoid glycoside, has been shown to exert antioxidant and antitumor effects. This study aimed to investigate whether SAL supplementation could delay the postovulatory oocyte aging process by alleviating oxidative stress. Here, we show that SAL supplementation decreases the malformation rate and recovers mitochondrial dysfunction including mitochondrial distribution, mitochondrial membrane potential (ΔΨ) and ATP content in aged oocytes. In addition, SAL treatment alleviates postovulatory aging-caused oxidative stress such as higher reactive oxygen species (ROS) level, lower glutathione (GSH) content and a reduced expression of antioxidant-related genes. Moreover, the cytoplasmic calcium ([Ca2+]c) and mitochondrial calcium ([Ca2+]mt) of SAL-treated oocytes return to normal levels. Notably, SAL suppresses the aging-induced DNA damage, early apoptosis and improves spindle assembly in aged oocytes, ultimately elevating the embryo developmental rates and embryo quality. Finally, the RNA-seq and confirmatory experience showed that SAL promotes protective autophagy in aged oocytes by activating the MAPK pathway. Taken together, our research suggests that supplementing SAL is an effective and feasible method for preventing postovulatory aging and preserving the oocyte quality, which potentially contributes to improving the successful rate of ART or TAI.

16.
Plant Sci ; 338: 111901, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37865209

RESUMO

Sunflowers are well-known ornamental plants, while sunflowers with red corolla are rare and the mechanisms underlying red coloration remain unclear. Here, a comprehensive analysis of metabolomics and transcriptomics on flavonoid pathway was performed to investigate the molecular mechanisms underlying the differential color formation between red sunflower Pc103 and two yellow sunflowers (Yr17 and Y35). Targeted metabolomic analysis revealed higher anthocyanin levels but lower flavonol content in Pc103 compared to the yellow cultivars. RNA-sequencing and phylogenetic analysis identified multiple genes involved in the flavonoid pathway, including series of structural genes and three MYB and bHLH genes. Specifically, HaMYBA and HabHLH1 were up-regulated in Pc103, whereas HaMYBF exhibited reduced expression. HaMYBA was found to interact with HabHLH1 in vivo and in vitro, while HaMYBF does not. Transient expression analysis further revealed that HabHLH1 and HaMYBA cooperatively regulate increased expression of dihydroflavonol 4-reductase (DFR), leading to anthocyanin accumulation. On the other hand, ectopic expression of HaMYBF independently modulates flavonol synthase (FLS) expression, but hindered anthocyanin production. Collectively, our findings suggest that the up-regulation of HaMYBA and HabHLH1, as well as the down-regulation of HaMYBF, contribute to the red coloration in Pc103. It offers a theoretical basis for improving sunflower color through genetic engineering.


Assuntos
Antocianinas , Helianthus , Antocianinas/metabolismo , Helianthus/genética , Helianthus/metabolismo , Filogenia , Flores/genética , Flores/metabolismo , Flavonoides/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
17.
J Funct Biomater ; 14(11)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37998116

RESUMO

Current research on the fatigue properties of degradable zinc alloy stents has not yet considered the issue of the fatigue life changing with material properties during the dynamic degradation process. Therefore, in this paper, we established a fatigue damage algorithm to study the fatigue problem affected by the changing of material properties during the dynamic degradation process of the stent under the action of pulsating cyclic loading. Three models: the dynamic degradation model, the dynamic degradation model under pulsating cyclic loading, and the coupled model of fatigue damage and dynamic degradation, were developed to verify the effect of fatigue damage on stent life. The results show that fatigue damage leads to a deeper degree of inhomogeneous degradation of the stent, which affects the service life of the stent. Fatigue damage is a factor that cannot be ignored. Therefore, when studying the mechanical properties and lifetime of degradable stents, incorporating fatigue damage into the study can help more accurately assess the lifetime of the stents.

18.
Artigo em Inglês | MEDLINE | ID: mdl-36833745

RESUMO

The study examined the influence of social support on depression, including the mediating role of psychological resilience and the moderating role of geography. Questionnaires were completed by 424 economically disadvantaged college students in two provinces, X, a coastal province, and Y, an inland province. The results indicated that (1) the social support of economically disadvantaged college students was positively correlated to psychological resilience (ß = 0.62, t = 11.22, p < 0.001); (2) the psychological resilience of economically disadvantaged college students was negatively correlated with depression (ß = -0.24, t = -10.3, p < 0.001); (3) the social support of economically disadvantaged college students was negatively correlated with depression (ß = -0.08, t = -2.85, p < 0.001); (4) the psychological resilience of economically disadvantaged college students played a partial mediating role between social support and depression; and (5) geography played a moderating role in the effect of social support on depression.


Assuntos
Depressão , Resiliência Psicológica , Humanos , Depressão/psicologia , Estudantes/psicologia , Apoio Social , Geografia
19.
Environ Sci Pollut Res Int ; 30(11): 28874-28888, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36401695

RESUMO

Development of efficient photocatalysts is vital for light-driven removal of refractory antibiotics. Herein, Bi2WO6 microspheres were successfully anchored on the surface of bentonite, and metallic Bi was reduced in-situ by a one-step solvothermal method. Notably, the Bi/Bi2WO6/BT with a mass ratio of 0.15:1:0.1 exhibited the best photocatalytic activity toward degradation of tetracycline (TC) and ciprofloxacin (CIP) after 120 min of visible light irradiation, and their reaction rate constants were 8.0 and 5.5 folds higher than that of pristine Bi2WO6, respectively. The boosted photocatalytic activity over Bi/Bi2WO6/BT was ascribed to the establishment of electrostatic repulsion and SPR effect, which synergistically promoted charges transfer, thus achieving more h+ and ·O2- radical generation. Moreover, possible TC and CIP degradation pathways over Bi/Bi2WO6/BT were proposed based on the identified intermediates, and most of the intermediates were less toxic than TC and CIP. The study provides options to develop high-efficiency photocatalytic composites for contaminants elimination using semiconductors and readily available bentonite.


Assuntos
Bentonita , Ressonância de Plasmônio de Superfície , Eletricidade Estática , Catálise , Antibacterianos , Ciprofloxacina , Luz , Tetraciclina
20.
Plants (Basel) ; 12(16)2023 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-37631208

RESUMO

Purple-grained wheat (Triticum aestivum L.) is an important germplasm source in crop breeding. Anthocyanin biosynthesis in the pericarps of purple-grained wheat is largely light-dependent; however, the regulatory mechanisms underlying light-induced anthocyanin accumulation in the wheat pericarp remain unknown. Here we determined that anthocyanins rapidly accumulate in the pericarps of the purple-grained wheat cultivar Heixiaomai 76 (H76) at 16 days after pollination under light treatment. Using transcriptome sequencing, differential gene expression analysis, and phylogenetic analysis, we identified two key genes involved in light signaling in wheat: ELONGATED HYPOCOTYL 5-7A (TaHY5-7A) and B-BOX-3B (TaBBX-3B). TaHY5-7A and TaBBX-3B were highly expressed in purple-grained wheat pericarps. The heterologous expression of TaHY5-7A partially restored the phenotype of the Arabidopsis (Arabidopsis thaliana) hy5 mutant, resulting in increased anthocyanin accumulation and a shortened hypocotyl. The heterologous expression of TaBBX-3B in wild-type Arabidopsis had similar effects. TaHY5-7A and TaBBX-3B were nucleus-localized, consistent with a function in transcription regulation. However, TaHY5-7A, which lacks a transactivation domain, was not sufficient to activate the expression of PURPLE PERICARP-MYB 1 (TaPpm1), the key anthocyanin biosynthesis regulator in purple pericarps of wheat. TaHY5-7A physically interacted with TaBBX-3B in yeast two-hybrid and bimolecular fluorescence complementation assays. Additionally, TaHY5-7A, together with TaBBX-3B, greatly enhanced the promoter activity of TaPpm1 in a dual luciferase assay. Overall, our results suggest that TaHY5-7A and TaBBX-3B collaboratively activate TaPpm1 expression to promote light-induced anthocyanin biosynthesis in purple-pericarp wheat.

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