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The polar auxin transport is required for proper plant growth and development. D6 PROTEIN KINASE (D6PK) is required for the phosphorylation of PIN-FORMED (PIN) auxin efflux carriers to regulate auxin transport, while the regulation of D6PK stabilization is still poorly understood. Here, we found that Cytosolic ABA Receptor Kinases (CARKs) redundantly interact with D6PK, and the interactions are dependent on CARKs' kinase activities. Similarly, CARK3 also could interact with paralogs of D6PK, including D6PKL1, D6PKL2, and D6PKL3. The genetic analysis shows that D6PK acts the downstream of CARKs to regulate Arabidopsis growth, including hypocotyl, leaf area, vein formation, and the length of silique. Loss-of-function of CARK3 in overexpressing GFP-D6PK plants leads to reduce the level of D6PK protein, thereby rescues plant growth. In addition, the cell-free degradation assays indicate that D6PK is degraded through 26 S proteasome pathway, while the phosphorylation by CARK3 represses this process in cells. In summary, D6PK stabilization by the CARK family is required for auxin-mediated plant growth and development.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/enzimologia , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Fosforilação , Ácidos Indolacéticos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Citosol/metabolismo , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Plantas Geneticamente ModificadasRESUMO
The platelet-derived growth factor (PDGF) and its receptor, PDGFRα, are critical for tissue development and injury repair. To track PDGFRα-expressing cells in vivo, we generated a knock-in mouse line that expresses green fluorescent protein (GFP) under the control of the PDGFRα promoter. This genetic tool enabled us to detect PDGFRα expression in various organs during both neonatal and adult stages. Additionally, we confirmed the correlation between endogenous PDGFRα and transgenic PDGFRα expression using mouse injury models, showing the potential of this genetic reporter for studying PDGFRα-mediated signaling pathways and developing therapeutic strategies. Overall, the PDGFRα-GFP knock-in mouse line serves as a valuable tool for investigating the biology of PDGFRα and its role in normal development and disease.
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Fibroblastos , Receptor alfa de Fator de Crescimento Derivado de Plaquetas , Camundongos , Animais , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Camundongos Transgênicos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Modelos Animais de Doenças , Fibroblastos/metabolismoRESUMO
Amoxicillin is widely used in the treatment of infectious diseases during pregnancy; however, the effects of prenatal amoxicillin exposure (PAE) on fetal development remain largely unknown. Therefore, this study aimed to investigate the toxic effects of PAE on fetal cartilage at different stage-, dose-, and course. Pregnant Kunming mice were orally administered 300 mg/kg·d (converted from clinical dose) amoxicillin on gestational days (GD) 10-12 or 16-18 (mid or late pregnancy stage), 150 or 300 mg/kg.d amoxicillin on GD16-18 (different doses), 300 mg/kg·d amoxicillin on GD16 (single course) or 16-18 (multiple courses), respectively. The fetal articular cartilage of the knee was collected on GD18. The number of chondrocytes and the expression of matrix synthesis/degradation, proliferation/apoptosis-related markers, and the TGF-ß signaling pathway were detected. The results showed that the number of chondrocytes and the expression of matrix synthesis markers were reduced in male fetal mice treated with PAE (GD16-18, 300 mg/kg.d, single course and multiple courses), whereas the above indices in female mice showed no changes. The inhibited expression of PCNA, increased expression of Caspase-3, and down-regulated expression of the TGF-ß signaling pathway were found in male PAE fetal mice. Accordingly, PAE exerted its "toxic effect window" on the knee cartilage development in male fetal mice, which manifested as reduced chondrocyte number and inhibited expression of matrix synthesis at a clinical dose of multiple courses in the late pregnancy stage. This study provides a theoretical and experimental basis for elucidating the risk of chondrodevelopmental toxicity associated with amoxicillin during pregnancy.
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Cartilagem Articular , Camundongos , Animais , Gravidez , Masculino , Feminino , Feto/metabolismo , Desenvolvimento Fetal , Fator de Crescimento Transformador beta/metabolismo , CondrócitosRESUMO
The excited state species and properties in low-dimensional semiconductors can be completely redefined by electron-lattice coupling or a polaronic effect. Here, by combining ultrafast broadband pump-probe spectroscopy and first-principles GW and Bethe-Salpeter equation calculations, we show semiconducting CrI3 as a prototypical 2D polaronic system with characteristic Jahn-Teller exciton polaron induced by symmetry breaking. A photogenerated electron and hole in CrI3 localize spontaneously in â¼0.9 ps and pair geminately to a Jahn-Teller exciton polaron with elongated Cr-I octahedra, large binding energy, and an unprecedentedly small exciton-exciton annihilation rate constant (â¼10-20 cm3 s-1). Coherent phonon dynamics indicates the localization is mainly triggered by the coherent nuclear vibration of the I-Cr-I out-of-plane stretch mode at 128.5 ± 0.1 cm-1. The excited state Jahn-Teller exciton polaron in CrI3 broadens the realm of 2D polaron systems and reveals the decisive role of coupled electron-lattice motion on excited state properties and exciton physics in 2D semiconductors.
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Cells and tissues are exposed to a wide range of mechanical stimuli during development, tissue homeostasis, repair, and regeneration. Over the past few decades, mechanosensitive ion channels (MSCs), as force-sensing integral membrane proteins, have attracted great attention with regard to their structural dynamics and mechanics at the molecular level and functions in various cells. Piezo-type MSC component 1 (Piezo1) is a newly discovered MSC; it is inherently mechanosensitive. However, which type of cells express Piezo1 in vivo remains unclear. To detect and trace Piezo1-expressing cells, we generated and characterized a novel tamoxifen-inducible Cre knock-in mouse line, Piezo1-CreER, which expresses CreER recombinase under the control of the endogenous Piezo1 promoter. Using this genetic tool, we detected the expression of Piezo1 in various cell types at the embryonic, neonatal, and adult stages. Our data showed that Piezo1 was highly expressed in endothelial cells in all the three stages, while the Piezo1 expression in epithelial cells was dynamic during development and growth. In summary, we established a new genetic tool, Piezo1-CreER, to study Piezo1-expressing cells in vivo during development, injury response, and tissue repair and regeneration.
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Células Endoteliais , Canais Iônicos , Animais , Células Endoteliais/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Tamoxifeno/farmacologiaRESUMO
Cytosolic ABA Receptor Kinases (CARKs) play a pivotal role in abscisic acid (ABA)-dependent pathway in response to dehydration, but their regulatory mechanism in ABA signaling remains unexplored. In this study, we showed that CARK4/5 of CARK family physically interacted with ABA receptors (RCARs/PYR1/PYLs), including RCAR3, RCAR11-RCAR14, while CARK2/7/11 only interacted with RCAR11-RCAR14, but not RCAR3. It indicates that the members in CARK family function redundantly and differentially in ABA signaling. RCAR12 can form heterodimer with RCAR3 in vitro and in vivo. Moreover, the members of CARK family can form homodimer or heterodimer in a kinase activity dependent manner. ITC (isothermal titration calorimetry) analysis demonstrated that the phosphorylation of RCAR12 by CARK1 enhanced the ABA binding affinity. The phosphor-mimic RCAR12T105D significantly displayed ABA-induced inhibition of the phosphatase ABI1 (ABA insensitive 1) activity, leading to upregulation of ABA-responsive genes RD29A and RD29B in cark157:RCAR12T105D transgenic plants, which exhibited ABA hypersensitive phenotype. The transcription factor ABI5 (ABA insensitive 5) activates the transcriptions of CARK1 and CARK3 by binding to ABA-response elements (ABREs) of their promoters. Collectively, our data imply that the dimeric CARKs phosphorylate homodimer or heterodimer ABA receptors, leading to monomerization for triggering ABA responses in Arabidopsis.
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Proteínas de Arabidopsis , Arabidopsis , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , FosforilaçãoRESUMO
Geometric constraint algorithms can solve phase ambiguity for fringe projection profilometry (FPP). However, they either require multiple cameras or suffer from a small measurement depth range. To overcome these limitations, this Letter proposes an algorithm combining orthogonal fringe projection and geometric constraints. A novel, to the best of our knowledge, scheme is developed to assess the reliabilities of the potential homologous points, which works with depth segmentation to determine the final HPs. With full consideration of lens distortions, the algorithm reconstructs two 3D results from every set of patterns. Experimental results verify that it can effectively and robustly measure discontinuous objects with complex motion over a large depth range.
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Depression is a neuropsychiatric disorder and has intrauterine developmental origins. This study aimed to confirm the depression susceptibility in offspring rats induced by prenatal dexamethasone exposure (PDE) and to further explore the intrauterine programming mechanism. Wistar rats were injected with dexamethasone (0.2 mg/kg·d) subcutaneously during the gestational days 9-20 and part of the offspring was given chronic stress at postnatal weeks 10-12. Behavioral results showed that the adult PDE female offspring was susceptible to depression, accompanied by increased hippocampal miR-134-5p expression and decreased sex-determining region Y-box 2 (SOX2) expression, as well as disorders of neural progenitor cells proliferation and hippocampal neurogenesis. The PDE female fetal rats presented consistent changes with the adult offspring, accompanied by the upregulation of glucocorticoid receptor (GR) expression and decreased sirtuin 1 (SIRT1) expression. We further found that the H3K9ac level of the miR-134-5p promoter was significantly increased in the PDE fetal hippocampus, as well as in adult offspring before and after chronic stress. In vitro, the changes of GR/SIRT1/miR-134-5p/SOX2 signal by dexamethasone were consistent with in vivo experiments, which could be reversed by GR receptor antagonist, SIRT1 agonist, and miR-134-5p inhibitor. This study confirmed that PDE led to an increased expression level as well as H3K9ac level of miR-134-5p by activating the GR/SIRT1 pathway in the fetal hippocampus and then inhibited the SOX2 expression. The programming effect mediated by the abnormal epigenetic modification could last from intrauterine to adulthood, which constitutes the intrauterine programming mechanism leading to hippocampal neurogenesis disorders and depression susceptibility in female offspring. Intrauterine programming mechanism for the increased depressive susceptibility in adult female offspring by prenatal dexamethasone exposure (PDE). GR, glucocorticoid receptor; SIRT1, sirtuin 1; SOX2, sex-determining region Y-box 2; NPCs, neuroprogenitor cells; H3K9ac, histone 3 lysine 9 acetylation; GRE, glucocorticoid response element.
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MicroRNAs , Efeitos Tardios da Exposição Pré-Natal , Adulto , Animais , Depressão/induzido quimicamente , Dexametasona/efeitos adversos , Feminino , Hipocampo/metabolismo , Humanos , MicroRNAs/genética , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Wistar , Receptores de Glucocorticoides/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismoRESUMO
PURPOSE: This study aimed to verify whether transplantation of dedifferentiated osteogenic bone marrow mesenchymal stem cells (De-BMSCs) at the tendon-bone interface could result in more bone formation than BMSC transplantation in anterior cruciate ligament (ACL) reconstruction. METHODS: BMSCs from femur and tibia of New Zealand White rabbit were subjected to osteogenic induction and then cultured in osteogenic factor-free medium; the obtained cell population was termed De-BMSCs. Bilateral ACL reconstruction was performed in 48 adult rabbits. Three groups were established: control group with alginate gel injection, BMSCs group with the BMSCs injection, and De-BMSCs group with the De-BMSCs injection. At week 4 and 12 postoperatively, tendon-bone healing by histologic staining, micro-computed tomography examination, and biomechanical test were evaluated. RESULTS: The expression of α1 chain of type I collagen, osteocalcin, and osteopontin at the tendon-bone interface in the De-BMSCs group was greater than in the control or BMSCs group. The bone volume/total volume by micro-computed tomography scan was significantly greater in the De-BMSCs group than that in the control group (P = .013) or BMSCs group (P = .045) at 4 weeks, and greater than that in the control group (P = .014) or BMSCs group (P = .017) at 12 weeks. The tunnel area was significantly smaller in the De-BMSCs group than in the control group (P = .013) or BMSCs group (P = .044) at 12 weeks. The failure load and stiffness in De-BMSCs group were both significantly enhanced at 4 and 12 weeks than control group or De-BMSCs group. CONCLUSIONS: De-BMSCs transplantation can promote bone formation at the tendon-bone interface better than BMSCs transplantation in ACL reconstruction and increase the early biomechanical strength of the reconstructed ACL CLINICAL RELEVANCE: De-BMSCs transplantation is a potential choice for enhancing early bone formation in the tunnel in ACL reconstruction.
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Reconstrução do Ligamento Cruzado Anterior , Células-Tronco Mesenquimais , Animais , Reconstrução do Ligamento Cruzado Anterior/métodos , Células da Medula Óssea , Osteogênese , Coelhos , Tendões/metabolismo , Microtomografia por Raio-XRESUMO
As an important equipment for high-speed railway (HSR) to obtain electric power from outside, the state of the pantograph will directly affect the operation safety of HSR. In order to solve the problems that the current pantograph detection method is easily affected by the environment, cannot effectively deal with the interference of external scenes, has a low accuracy rate and can hardly meet the actual operation requirements of HSR, this study proposes a pantograph detection algorithm. The algorithm mainly includes three parts: the first is to use you only look once (YOLO) V4 to detect and locate the pantograph region in real-time; the second is the blur and dirt detection algorithm for the external interference directly affecting the high-speed camera (HSC), which leads to the pantograph not being detected; the last is the complex background detection algorithm for the external complex scene "overlapping" with the pantograph when imaging, which leads to the pantograph not being recognized effectively. The dirt and blur detection algorithm combined with blob detection and improved Brenner method can accurately evaluate the dirt or blur of HSC, and the complex background detection algorithm based on grayscale and vertical projection can greatly reduce the external scene interference during HSR operation. The algorithm proposed in this study was analyzed and studied on a large number of video samples of HSR operation, and the precision on three different test samples reached 99.92%, 99.90% and 99.98%, respectively. Experimental results show that the algorithm proposed in this study has strong environmental adaptability and can effectively overcome the effects of complex background and external interference on pantograph detection, and has high practical application value.
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Algoritmos , Diagnóstico por Imagem , Diagnóstico por Imagem/métodosRESUMO
Despite grand advances in Zn-air batteries in recently years, their commercialization remains challenging due largely to the lack of efficient bifunctional oxygen catalysts. Herein, we report the crafting of a bifunctional electrocatalyst comprising ultrafine alloyed FeNi nanoparticles encapsulated within N-doped layered carbon nanosheets (denoted FeNi/N-LCN) for high-efficiency Zn-air batteries. The FeNi/N-LCN electrocatalyst is yielded via the coordination of triphenylimidazole-containing polyaniline (TPANI) oligomer with Fe- and Ni-containing precursors, followed by hydrogen binding with melamine and subsequent pyrolysis. The as-constructed FeNi/N-LCN manifests outstanding activity and stability toward both the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The primary Zn-air battery assembled with FeNi/N-LCN delivers both high specific capacity and peak power density. Remarkably, the rechargeable Zn-air battery can be repeatedly charged and discharged for 1100 h at 5 mA cm-2 and for 600 h at 10 mA cm-2, representing the highest cycling stability among various reported Zn-air batteries.
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The phytohormone abscisic acid (ABA) plays an important role in the ability of plants to cope with drought stress. As core members of the ABA signaling pathway, protein phosphatase type 2Cs (PP2Cs) have been reported in many species. However, the functions of MdPP2Cs in apple (Malus domestica) are unclear. In this study, we identified two PP2C-encoding genes, MdPP2C24/37, with conserved PP2C catalytic domains, using sequence alignment. The nucleus-located MdPP2C24/37 genes were induced by ABA or mannitol in apple. Genetic analysis revealed that overexpression of MdPP2C24/37 in Arabidopsis thaliana led to plant insensitivity to ABA or mannitol treatment, in terms of inhibiting seed germination and overall seedling establishment. The expression of stress marker genes was upregulated in MdPP2C24/37 transgenic lines. At the same time, MdPP2C24/37 transgenic lines displayed inhibited ABA-mediated stomatal closure, which led to higher water loss rates. Moreover, when exposed to drought stress, chlorophyll levels decreased and MDA and H2O2 levels accumulated in the MdPP2C24/37 transgenic lines. Further, MdPP2C24/37 interacted with MdPYL2/12 in vitro and vivo. The results indicate that MdPP2C24/37 act as negative regulators in response to ABA-mediated drought resistance.
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Arabidopsis , Malus , Arabidopsis/metabolismo , Malus/genética , Malus/metabolismo , Peróxido de Hidrogênio/metabolismo , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Manitol/metabolismoRESUMO
BACKGROUND: Phylogenetic profiling is widely used to predict novel members of large protein complexes and biological pathways. Although methods combined with phylogenetic trees have significantly improved prediction accuracy, computational efficiency is still an issue that limits its genome-wise application. RESULTS: Here we introduce a new tree-based phylogenetic profiling algorithm named GFICLEE, which infers common single and continuous loss (SCL) events in the evolutionary patterns. We validated our algorithm with human pathways from three databases and compared the computational efficiency with current tree-based with 10 different scales genome dataset. Our algorithm has a better predictive performance with high computational efficiency. CONCLUSIONS: The GFICLEE is a new method to infers genome-wide gene function. The accuracy and computational efficiency of GFICLEE make it possible to explore gene functions at the genome-wide level on a personal computer.
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Genoma , Genômica , Algoritmos , Humanos , FilogeniaRESUMO
Axially, epitaxially organizing nano-objects of distinct compositions and structures into superlattice nanowires enables full utilization of sunlight, readily engineered band structures, and tunable geometric parameters to fit carrier transport, thus holding great promise for optoelectronics and solar-to-fuel conversion. To maximize their efficiency, the general and high-precision synthesis of colloidal axial superlattice nanowires (ASLNWs) with programmable compositions and structures is the prerequisite; however, it remains challenging. Here, we report an axial encoding methodology toward the ASLNW library with precise control over their compositions, dimensions, crystal phases, interfaces, and periodicity. Using a predesigned, editable nanoparticle framework that offers the synthetic selectivity, we are able to chemically decouple adjacent sub-objects in ASLNWs and thus craft them in a controlled approach, yielding a library of distinct ASLNWs. We integrate therein plasmonic, metallic, or near-infrared-active chalcogenides, which hold great potential in solar energy conversion. Such synthetic capability enables a performance boost in target applications, as we report order-of-magnitude enhanced photocatalytic hydrogen production rates using optimized ASLNWs compared to corresponding solo objects. Furthermore, it is expected that such unique superlattice nanowires could bring out new phenomena.
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Tartary buckwheat is a kind of plant which can be used as medicine as well as edible. Abscisic acid (ABA) signaling plays an important role in the response of plants such as tartary buckwheat to drought and other stress. However, there are not many studies on tartary buckwheat by ABA treatment. In this study, the germination, root length, stoma, and anthocyanin accumulation of tartary buckwheat were all significantly affected by ABA. ABA signaling is important for plants to respond to drought and other stresses, the bZIP gene family is an important member of the ABA signaling pathway. Through the analysis of the origin relationship between tartary buckwheat bZIP family and its related species, 19 bZIP genes in tartary buckwheat were found to be relatively conserved, which laid a foundation for further study of bZIP family. The qRT-PCR results showed that most of the group members were induced by ABA treatment, including 0, 15, 30, 50, 70 µM ABA and 0, 0.5, 2, 4, 8, 16, 24 h ABA treatment. These results suggested that ABA could affect the growth and development of tartary buckwheat, and FtbZIPs might have different functions in the response of tartary buckwheat to drought. This study will be helpful to further analyze the genetic breeding and economic value of tartary buckwheat resistance.
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Ácido Abscísico/farmacologia , Fagopyrum/efeitos dos fármacos , Fagopyrum/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Ácido Abscísico/metabolismo , Antocianinas/metabolismo , Secas , Fagopyrum/crescimento & desenvolvimento , Fagopyrum/metabolismo , Germinação/efeitos dos fármacos , Filogenia , Melhoramento Vegetal , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: To evaluate trends in the in-hospital mortality rate for pediatric cardiac surgery procedures between 2005 and 2017 in our center, and to discuss the mortality characteristics of children's CHD after thoracotomy. METHODS: This retrospective data were collected from medical records of children underwent CHD surgery between 2005 and 2017. RESULTS: A total of 19,114 children with CHD underwent surgery and 444 children died, with the in-hospital mortality was 2.3%. Complex mixed defect CHD had the highest fatality rate (8.63%), left obstructive lesion CHD had the second highest fatality rate (4.49%), right to left shunt CHD had the third highest mortality rate (3.51%), left to right shunt CHD had the lowest mortality rate (χ2 = 520.3,P < 0.05). The neonatal period has the highest mortality rate (12.17%), followed by infant mortality (2.58%), toddler age mortality (1.16%), and preschool age mortality (0.94%), the school age and adolescent mortality rate was the lowest (χ2 = 529.3,P < 0.05). In addition, the fatality rate in boys was significantly higher than that in girls (2.77% versus 1.62%, χ2 = 26.4, P < 0.05). CONCLUSIONS: The mortality rate of CHD surgery in children decreased year by year. The younger the age and the more complicated the cyanotic heart disease, the higher the mortality rate may be.
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Procedimentos Cirúrgicos Cardíacos , Cardiopatias Congênitas , Adolescente , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Mortalidade Hospitalar , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Fatores de RiscoRESUMO
The rational design and facile synthesis of metal organic framework (MOF)-derived carbon materials with high oxygen reduction reaction (ORR) activity still remains challenging. Herein, we report on a simple yet robust route to dual-shelled Co, N, and S co-doped hollow carbon nanocages (denoted Co-N/S-DSHCN) with outstanding ORR performance. The concurrent compositional and structural engineering of the zeolitic imidazolate framework (ZIF-67), enabled by its coating with trithiocyanuric acid (TCA), yields core-shelled precursor particles which are subsequently carbonized into Co-N/S-DSHCN. Notably, Co-N/S-DSHCN-3.5 outperforms the commercial Pt/C, representing a +25 mV onset potential (Eon) and a +43 mV half-wave potential (E1/2) in 0.1 M KOH and a comparable E1/2 to Pt/C in 0.5 M H2SO4, respectively. Such impressive ORR activities of Co-N/S-DSHCN-3.5 originate from the effective synergy of Co, N, and S co-doping (i.e., a compositional tuning) in conjunction with a unique dual-shelled hollow architecture containing hierarchical porosity (i.e., a structural tailoring).
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Uridine diphosphate-glucosyltransferases (UGTs) maintain abscisic acid (ABA) homeostasis in Arabidopsis thaliana by converting ABA to abscisic acid-glucose ester (ABA-GE). UGT71C5 plays an important role in the generation of ABA-GE. Abscisic acid receptors are crucial upstream components of the ABA signaling pathway, but how UGTs and ABA receptors function together to modulate ABA levels is unknown. Here, we demonstrated that the ABA receptors RCAR12/13 and UGT71C5 maintain ABA homeostasis in Arabidopsis following rehydration under drought stress. Biochemical analyses show that UGT71C5 directly interacted with RCAR8/12/13 in yeast cells, and the interactions between UGT71C5 and RCAR12/13 were enhanced by ABA treatment. Enzyme activity analysis showed that ABA-GE contents were significantly elevated in the presence of RCAR12 or RCAR13, suggesting that these ABA receptors enhance the activity of UGT71C5. Determination of the content of ABA and ABA-GE in Arabidopsis following rehydration under drought stress revealed that ABA-GE contents were significantly higher in Arabidopsis plants overexpressing RCAR12 and RCAR13 than in non-transformed plants and plants overexpressing RCAR11 following rehydration under drought stress. These observations suggest that RCAR12 and RCAR13 enhance the activity of UGT71C5 to glycosylate excess ABA into ABA-GE following rehydration under drought stress, representing a rapid mechanism for regulating plant growth and development.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Glucosiltransferases/metabolismo , Homeostase , Receptores de Superfície Celular/metabolismo , Arabidopsis/genética , Glicosilação , Cinética , Plantas Geneticamente Modificadas , Ligação ProteicaRESUMO
Abscisic acid (ABA) signaling is a vital plant signaling pathway for plant responses to stress conditions. ABA treatment can alter global gene expression patterns and cause significant phenotypic changes. We investigated the responses to ABA treatment during flowering in Arabidopsis thaliana. Dipping the flowers of CARK3 T-DNA mutants in ABA solution, led to less reduction of pollen fertility than in the wild type plants (Col-0). We demonstrated that PMEIL, a gene located downstream of CARK3, directly affects pollen fertility. Due to the close arrangement of CARK3 and PMEIL, CARK3 expression represses transcription of PMEIL in an ABA-dependent manner through transcriptional interference. Our study uncovers a molecular mechanism underlying ABA-mediated pollen sterility and provides an example of how transcriptional interference caused by close arrangement of genes may mediate stress responses during plant reproduction.
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Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Reguladores de Crescimento de Plantas/fisiologia , Infertilidade das Plantas/genética , Pólen/genética , Proteínas Serina-Treonina Quinases/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/fisiologia , Ordem dos Genes/genética , Ordem dos Genes/fisiologia , Germinação , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Infertilidade das Plantas/fisiologia , Pólen/fisiologia , Proteínas Serina-Treonina Quinases/fisiologiaRESUMO
Epidemiology suggests that adverse environmental exposure during pregnancy may predispose children to hypercholesterolemia in adulthood. This study aimed to demonstrate hypercholesterolemia induced by prenatal dexamethasone exposure (PDE) in adult male offspring rats and explore the intrauterine programming mechanisms. Pregnant Wistar rats were injected subcutaneously with dexamethasone (0, 0.1, 0.2, and 0.4 mg/kgâd) from gestational days (GD) 9 to 21, and the serum and liver of the male offsprings were collected at GD21, postnatal week (PW) 12 and 28. Furthermore, the effects of dexamethasone on the expression of low-density lipoprotein receptor (LDLR) and its epigenetic mechanism was confirmed in the bone marrow mesenchymal stem cells (BMSCs) hepatoid differentiated cells and continuous hepatocyte line. PDE could reduce the birth weight of male offsprings, increase the serum total cholesterol (TCH) level in adult rats, and decrease the liver low-density lipoprotein receptor (LDLR) expression. Serum TCH level and liver LDLR expression were decreased in PDE male fetuses in utero (GD21). Moreover, PDE increased the translocation of the glucocorticoid receptor (GR) in the fetal liver, the expression of DiGeorge syndrome critical region 8 gene (DGCR8), the pre- and post-natal expression of miR-148a. The results of PDE offspring in vivo and in vitro exhibited similar changes. These changes could be reversed by overexpressing LDLR, inhibiting miR-148a or GR. PDE caused hypercholesterolemia in male adult offspring rats, which was mediated via dexamethasone activated intrauterine hepatic GR, enhanced the expression of DGCR8 and miR-148a, thereby reducing the expression of LDLR, leading to impaired liver cholesterol reverse transport function, and finally causing hypercholesterolemia in adult rats.