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The two-dimensional (2D) honeycomb lattice has attracted intensive research interest due to the appearance of Dirac-type band structures as the consequence of two sublattices in the honeycomb structure. Introducing strong spin-orbit coupling (SOC) leads to a gap opening at the Dirac point, transforming the honeycomb lattice into a 2D topological insulator as a platform for the quantum spin Hall effect (QSHE). In this work, we realize a 2D honeycomb-structured film with tellurium, the heaviest nonradioactive element in Group VI, namely, tellurene, via molecular beam epitaxy. We revealed the gap opening of 160 meV at the Dirac point due to the strong SOC in the honeycomb-structured tellurene by angle-resolved photoemission spectroscopy. The topological edge states of tellurene are detected via scanning tunneling microscopy/spectroscopy. These results demonstrate that tellurene is a novel 2D honeycomb lattice with strong SOC, and they unambiguously prove that tellurene is a promising candidate for a room-temperature QSHE system.
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Lesion mimic mutants (LMMs) refer to the spontaneous formation of disease-like spots on leaves without any obvious pathogen infection. The LMM genes can regulate plant immunity, thus promoting the defense of crops against pathogens. However, there is a lack of systematic understanding of the regulatory mechanism of LMMs in wheat. This study identified a wheat LMM TaCAT2, a homolog of the Arabidopsis CAT2. The prediction of the cis-regulatory element revealed that TaCAT2 was involved in the response of plants to various hormones and stresses. RT-qPCR analysis indicated that TaCAT2 was significantly up-regulated by NaCl, drought, and Fusarium graminearum infection. Fluorescence microscopy showed that the TaCAT2 was localized to the peroxisome. Overexpression of TaCAT2 enhanced plant resistance to Phytophthora infestation and F. graminearum by constitutionally activating SA and JA pathways. VIGS of TaCAT2 enhanced the sensitivity of wheat to F. graminearum. Further, TaCAT2 enhanced stress resistance by scavenging the excessive ROS and increasing the activities of antioxidative enzymes. This study lays the basis for the functional identification of TaCAT2 and its applicability in the disease resistance of wheat.
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In this work, flexible Cu2-xS films on nylon membranes are prepared by combining a simple hydrothermal synthesis and vacuum filtration followed by hot pressing. The films consist of Cu2S and Cu1.96S two phases with grain sizes from nano to submicron. Doping Se on the S site not only increases the Cu1.96S content in the Cu2-xS to increase carrier concentration but also modifies electronic structure, thereby greatly improves the electrical properties of the Cu2-xS. Specifically, an optimal composite film with a nominal composition of Cu2-xS0.98Se0.02 exhibits a high power factor of ~150.1 µW m-1 K-2 at 300 K, which increases by ~138% compared to that of the pristine Cu2-xS film. Meanwhile, the composite film shows outstanding flexibility (~97.2% of the original electrical conductivity is maintained after 1500 bending cycles with a bending radius of 4 mm). A four-leg flexible thermoelectric (TE) generator assembled with the optimal film generates a maximum power of 329.6 nW (corresponding power density of 1.70 W m-2) at a temperature difference of 31.1 K. This work provides a simple route to the preparation of high TE performance Cu2-xS-based films.
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Triclosan (TCS) is a broad-spectrum antibiotic widely used in various personal care products. Research has found that exposure to TCS can cause toxic effects on organisms including neurotoxicity, cardiotoxicity, disorders of lipid metabolism, and abnormal vascular development, and the corresponding toxic mechanisms are gradually delving into the level of abnormal expression of miRNA regulating gene expression. Although the downstream mechanism of TCS targeting miRNA abnormal expression to induce toxicity is gradually improving, its upstream mechanism is still in a fog. Starting from the abnormal expression data of circRNA in zebrafish larvae induced by TCS, this study conducted a hierarchical analysis of the expression levels of all circRNAs, differential circRNAs, and trend circRNAs, and identified 29 key circRNA events regulating miRNA abnormal expression. In combination with GO and KEGG, the effects of TCS exposure were analyzed from the function and signaling pathway of the corresponding circRNA host gene. Furthermore, based on existing literature evidence about the biological toxicity induced by TCS targeting miRNA as data support, a competing endogenous RNAs (ceRNA) network characterizing the regulatory relationship between circRNA and miRNA was constructed and optimized. Finally, a comprehensive Adverse Outcome Pathway (AOP) framework of multiple levels of events including circRNA, miRNA, mRNA, pathway, and toxicity endpoints was established to systematically elucidate the toxic mechanism of TCS. Moreover, the rationality of the AOP framework was verified from the expression level of miRNA and adverse outcomes such as neurotoxicity, cardiotoxicity, oxidative stress, and inflammatory response by knockdown of circRNA48. This paper not only provides the key circRNA events for exploring the upstream mechanism of miRNA regulating gene expression but also provides an AOP framework for comprehensively demonstrating the toxicity mechanism of TCS on zebrafish, which is a theoretical basis for subsequent hazard assessment and prevention and control of TCS.
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MicroRNAs , RNA Circular , Triclosan , Peixe-Zebra , Animais , Peixe-Zebra/genética , RNA Circular/genética , MicroRNAs/genética , Triclosan/toxicidade , Rotas de Resultados Adversos , Poluentes Químicos da Água/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Larva/efeitos dos fármacos , Larva/genéticaRESUMO
Immunotherapy has now garnered significant attention as an essential component in cancer therapy during this new era. However, due to immune tolerance, immunosuppressive environment, tumor heterogeneity, immune escape, and other factors, the efficacy of tumor immunotherapy has been limited with its application to very small population size. Energy metabolism not only affects tumor progression but also plays a crucial role in immune escape. Tumor cells are more metabolically active and need more energy and nutrients to maintain their growth, which causes the surrounding immune cells to lack glucose, oxygen, and other nutrients, with the result of decreased immune cell activity and increased immunosuppressive cells. On the other hand, immune cells need to utilize multiple metabolic pathways, for instance, cellular respiration, and oxidative phosphorylation pathways to maintain their activity and normal function. Studies have shown that there is a significant difference in the energy expenditure of immune cells in the resting and activated states. Notably, competitive uptake of glucose is the main cause of impaired T cell function. Conversely, glutamine competition often affects the activation of most immune cells and the transformation of CD4+T cells into inflammatory subtypes. Excessive metabolite lactate often impairs the function of NK cells. Furthermore, the metabolite PGE2 also often inhibits the immune response by inhibiting Th1 differentiation, B cell function, and T cell activation. Additionally, the transformation of tumor-suppressive M1 macrophages into cancer-promoting M2 macrophages is influenced by energy metabolism. Therefore, energy metabolism is a vital factor and component involved in the reconstruction of the tumor immune microenvironment. Noteworthy and vital is that not only does the metabolic program of tumor cells affect the antigen presentation and recognition of immune cells, but also the metabolic program of immune cells affects their own functions, ultimately leading to changes in tumor immune function. Metabolic intervention can not only improve the response of immune cells to tumors, but also increase the immunogenicity of tumors, thereby expanding the population who benefit from immunotherapy. Consequently, identifying metabolic crosstalk molecules that link tumor energy metabolism and immune microenvironment would be a promising anti-tumor immune strategy. AMPK (AMP-activated protein kinase) is a ubiquitous serine/threonine kinase in eukaryotes, serving as the central regulator of metabolic pathways. The sequential activation of AMPK and its associated signaling cascades profoundly impacts the dynamic alterations in tumor cell bioenergetics. By modulating energy metabolism and inflammatory responses, AMPK exerts significant influence on tumor cell development, while also playing a pivotal role in tumor immunotherapy by regulating immune cell activity and function. Furthermore, AMPK-mediated inflammatory response facilitates the recruitment of immune cells to the tumor microenvironment (TIME), thereby impeding tumorigenesis, progression, and metastasis. AMPK, as the link between cell energy homeostasis, tumor bioenergetics, and anti-tumor immunity, will have a significant impact on the treatment and management of oncology patients. That being summarized, the main objective of this review is to pinpoint the efficacy of tumor immunotherapy by regulating the energy metabolism of the tumor immune microenvironment and to provide guidance for the development of new immunotherapy strategies.
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Recent studies have shown that silver selenide is a promising thermoelectric material at room temperature. Herein, flexible films with a nominal composition of (Ag1-xCux)2Se are prepared by a simple and efficient one-pot method combined with vacuum-assisted filtration and hot pressing. The thermoelectric properties of the films are regulated by both cationic doping and a dual-phase strategy via a wet chemical method. As the x increases, not only Cu is doped into the Ag2Se, but different new phases (CuAgSe and/or CuSe2) also appear. The (Ag1-xCux)2Se film with x = 0.02 composed of Cu-doped Ag2Se and CuAgSe shows a high PF of â¼2540 µW m-1 K-2 (ZT â¼ 0.90) and outstanding flexibility at room temperature. The high thermoelectric properties of the film are due to the effect of Cu doping and the CuAgSe phase, including the increase in electrical conductivity caused by doping, the enhanced phonon scattering at the Ag2Se/CuAgSe interface, and the interaction between the energy filtering effect and the doping effect. In addition to the high output performance (PDmax = 28.08 W m-2, ΔT = 32.2 K), the flexible device assembled with the (Ag0.98Cu0.02)2Se film also has potential applications as a temperature sensor.
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Growth-regulating factors (GRFs) play crucial roles in plant growth, development, hormone signaling, and stress response. Despite their significance, the roles of GRFs in ginger remain largely unknown. Herein, 31 ginger ZoGRFs were identified and designated as ZoGRF1-ZoGRF31 according to their phylogenetic relationships. All ZoGRFs were characterized as unstable, hydrophilic proteins, with 29 predicted to be located in the nucleus. Functional cis-elements related to growth and development were enriched in ZoGRF's promoter regions. RNA-seq and RT-qPCR analysis revealed that ZoGRF12, ZoGRF24, and ZoGRF28 were highly induced in various growth and development stages, displaying differential regulation under waterlogging, chilling, drought, and salt stresses, indicating diverse expression patterns of ZoGRFs. Transient expression analysis in Nicotiana benthamiana indicated that overexpressing ZoGRF28 regulated the transcription levels of salicylic acid, jasmonic acid, and pattern-triggered immunity-related genes, increased chlorophyll content and contributed to reduced disease lesions and an increased net photosynthetic rate. This research lays the foundation for further understanding the biological roles of ZoGRFs.
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Zingiber officinale , Zingiber officinale/genética , Filogenia , Fotossíntese , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
The assembly of oligopeptide and polypeptide molecules can reconstruct various ordered advanced structures through intermolecular interactions to achieve protein-like biofunction. Here, we develop a "molecular velcro"-inspired peptide and gelatin co-assembly strategy, in which amphiphilic supramolecular tripeptides are attached to the molecular chain of gelatin methacryloyl via intra-/intermolecular interactions. We perform molecular docking and dynamics simulations to demonstrate the feasibility of this strategy and reveal the advanced structural transition of the co-assembled hydrogel, which brings more ordered ß-sheet content and 10-fold or more compressive strength improvement. We conduct transcriptome analysis to reveal the role of co-assembled hydrogel in promoting cell proliferation and chondrogenic differentiation. Subcutaneous implantation evaluation confirms considerably reduced inflammatory responses and immunogenicity in comparison with type I collagen. We demonstrate that bone mesenchymal stem cells-laden co-assembled hydrogel can be stably fixed in rabbit knee joint defects by photocuring, which significantly facilitates hyaline cartilage regeneration after three months. This co-assembly strategy provides an approach for developing cartilage regenerative biomaterials.
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Cartilagem Articular , Cartilagem , Animais , Coelhos , Simulação de Acoplamento Molecular , Cartilagem/fisiologia , Hidrogéis/química , Materiais Biocompatíveis/química , Diferenciação Celular , Peptídeos , Conformação Proteica , Engenharia Tecidual , CondrogêneseRESUMO
Skin has a protein microenvironment dominated by functional collagen fibers, while oxidative stress caused by injury can greatly slow down the progress of wound healing. Here, methacrylated dopamine was incorporated into methacrylated silk fibroin molecule chains to develop an injectable hydrogel with photocuring properties for constructing an antioxidant skin protein microenvironment. This silk fibroin-based hydrogel (SF-g-SDA) showed good tensile and adhesion properties for adapting to the wound shape and skin movement, exhibited stable mechanical properties, good biodegradability and cytocompatibility, and promoted cell adhesion and vascularization in vitro. In addition, its phenolic hydroxyl-mediated antioxidant properties effectively protected cells from damage caused by oxidative stress and supported normal cellular life activities. In animal experiments, SF-g-SDA achieved better skin repair effects in comparison to commercial Tegaderm™ in vivo, showing its ability to accelerate wound healing, improve collagen deposition and alignment in newly fabricated tissues, and promote neovascularization and hair follicle formation. These experimental results indicated that the SF-g-SDA hydrogel is a promising wound dressing.
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Fibroínas , Animais , Fibroínas/farmacologia , Antioxidantes/farmacologia , Hidrogéis/farmacologia , Cicatrização , Colágeno/metabolismoRESUMO
Triclosan (TCS), a prevalent contaminant in aquatic ecosystems, has been identified as a potential threat to both aquatic biota and human health. Despite its widespread presence, research into the immunotoxic effects of TCS on aquatic organisms is limited, and the underlying mechanisms driving these effects remain largely unexplored. Herein, we investigated the developmental and immune toxicities of environmentally relevant concentrations of TCS in zebrafish, characterized by morphological anomalies, histopathological impairments, and fluctuations in cytological differentiation and biomarkers following both acute (from 6 to 72/120 hpf) and chronic exposure periods (from 30 to 100 dpf). Specifically, acute exposure to TCS resulted in a significant increase in innate immune cells, contrasted by a marked decrease in T cells. Furthermore, we observed that TCS exposure elicited oxidative stress and a reduction in global m6A levels, alongside abnormal expressions within the m6A modification enzyme system in zebrafish larvae. Molecular docking studies suggested that mettl3 might be a target molecule for TCS interaction. Intriguingly, the knock-down of mettl3 mirrored the effects of TCS exposure, adversely impacting the growth and development of zebrafish, as well as the differentiation of innate immune cells. These results provide insights into the molecular basis of TCS-induced immunotoxicity through m6A-RNA epigenetic modification and aid in assessing its ecological risks, informing strategies for disease prevention linked to environmental contaminants.
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Triclosan , Poluentes Químicos da Água , Animais , Humanos , Triclosan/toxicidade , Triclosan/metabolismo , Peixe-Zebra/metabolismo , Regulação para Baixo , Metilação de RNA , Ecossistema , Simulação de Acoplamento Molecular , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismoRESUMO
The domains of unknown function (DUF) superfamilies contain proteins with conserved amino acid sequences without known functions. Among them, DUF668 was indicated widely involving the stress response of plants. However, understanding ZoDUF668 is still lacking. Here, 12 ZoDUF668 genes were identified in ginger by the bioinformatics method and unevenly distributed on six chromosomes. Conserved domain analysis showed that members of the same subfamily had similar conserved motifs and gene structures. The promoter region of ZoDUF668s contained the light, plant hormone and stress-responsive elements. The prediction of miRNA targeting relationship showed that nine ginger miRNAs targeted four ZoDUF668 genes through cleavage. The expression patterns of 12 ZoDUF668 genes under biotic and abiotic stress were analyzed using RT-qPCR. The results showed that the expression of seven ZoDUF668 genes was significantly downregulated under Fusarium solani infection, six ZoDUF668 genes were upregulated under cold stress, and five ZoDUF668 genes were upregulated under waterlogging stress. These results indicate that the ZoDUF668 gene has different expression patterns under different stress conditions. This study provides excellent candidate genes and provides a reference for stress-resistance research in ginger.
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Fusariose , MicroRNAs , Zingiber officinale , Zingiber officinale/genética , Sequência de Aminoácidos , Resposta ao Choque Frio/genética , Biologia Computacional , MicroRNAs/genéticaRESUMO
Guanosine pentaphosphate and guanosine tetraphosphate are collectively called (p)ppGpp (Guanosine tetraphosphate and pentaphosphate). (p)ppGpp content in plants is affected by conditions such as light, salt, pH, UV light, and environmental phytohormones. The synthesis and hydrolysis of (p)ppGpp in plants is accomplished by a class of proteins called RSH (RelA/SpoT homologs). To date, a systematic and comprehensive genome-wide analysis of the RSH gene family in wheat and its closely related species has not been conducted. In this study, 15, 14, 12, and 8 members of RSH were identified in wheat (Triticum aestivum), Triticum dicoccoides, Triticum urartu and Aegilops tauschii respectively. Based on the conserved structural domains of the RSH genes, the TaRSHs have been categorized into TaRSH and TaCRSH. The gene duplications in the TaRSH gene family were all identified as segmental duplications indicating that the TaRSH family plays a significant role in expansion and that segmental duplications maintain a degree of genetic stability. Through the analysis of transcriptome data and RT-qPCR experiments, it was observed that the expression levels of TaRSHs were upregulated in response to abiotic stress. This upregulation suggests that TaRSHs play a crucial role in enhancing the resilience of wheat to adverse environmental conditions during its growth and development. Their increased expression likely contributes to the acquisition of stress tolerance mechanisms in wheat. Especially under NaCl stress, the expression levels increased most significantly. The more detailed systematic analysis provided in this article will help us understand the role of TaRSHs and provide a reference for further research on its molecular biological functions in wheat.
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Sugars will eventually be exported transporters (SWEETs) are a novel class of sugar transport proteins that play a crucial role in plant growth, development, and response to stress. However, there is a lack of systematic research on SWEETs in Capsicum annuum L. In this study, 33 CaSWEET genes were identified through bioinformatics analysis. The Ka/Ks analysis indicated that SWEET genes are highly conserved not only among peppers but also among Solanaceae species and have experienced strong purifying selection during evolution. The Cis-elements analysis showed that the light-responsive element, abscisic-acid-responsive element, jasmonic-acid-responsive element, and anaerobic-induction-responsive element are widely distributed in the promoter regions of CaSWEETs. The expression pattern analysis revealed that CaSWEETs exhibit tissue specificity and are widely involved in pepper growth, development, and stress responses. The post-transcription regulation analysis revealed that 20 pepper miRNAs target and regulate 16 CaSWEETs through cleavage and translation inhibition mechanisms. The pathogen inoculation assay showed that CaSWEET16 and CaSWEET22 function as susceptibility genes, as the overexpression of these genes promotes the colonization of pathogens, whereas CaSWEET31 functions as a resistance gene. In conclusion, through systematic identification and characteristic analysis, a comprehensive understanding of CaSWEET was obtained, which lays the foundation for further studies on the biological functions of SWEET genes.
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Capsicum , Capsicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Genes de Plantas , Família Multigênica , Regulação da Expressão Gênica de Plantas , FilogeniaRESUMO
Copper-sulfide-based materials have attracted noteworthy attention as thermoelectric materials due to rich elemental reserves, non-toxicity, low thermal conductivity, and adjustable electrical properties. However, research on the flexible thermoelectrics of copper sulfide has not yet been reported. In this work, we developed a facile method to prepare flexible Mn-doped Cu2-xS films on nylon membranes. First, nano to submicron powders with nominal compositions of Cu2-xMnyS (y = 0, 0.01, 0.03, 0.05, 0.07) were synthesized by a hydrothermal method. Then, the powders were vacuum-filtrated on nylon membranes and finally hot-pressed. Phase composition and microstructure analysis revealed that the films contained both Cu2S and Cu1.96S, and the size of the grains was ~20-300 nm. By Mn doping, there was an increase in carrier concentration and mobility, and ultimately, the electrical properties of Cu2-xS were improved. Eventually, the Cu2-xMn0.05S film showed a maximum power factor of 113.3 µW m-1 K-2 and good flexibility at room temperature. Moreover, an assembled four-leg flexible thermoelectric generator produced a maximum power of 249.48 nW (corresponding power density ~1.23 W m-2) at a temperature difference of 30.1 K, and had good potential for powering low-power-consumption wearable electronics.
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Whereas previous research shows that union membership is associated with improved health, static measurements have been used to test dynamic theories linking the two. We construct a novel measure of cumulative unionization, tracking individuals across their entire careers, to examine health consequences in older adulthood. We use data from the Panel Study of Income Dynamics (1970-2019) and predict self-rated health, functional limitations, and chronic health conditions in ages 60 to 79 using cumulative unionization measured during respondents' careers. Results from growth models show that unionized careers are associated with .25 SD to .30 SD improvements in health among older adults across all measures. Analyses of life course mechanisms reveal heterogeneous effects across unionization timing, age in older adulthood, and birth cohort. Moreover, subgroup analyses reveal unionization to partially, but not fully, ameliorate disparities based on privileged social positions. Our findings reveal a substantial and novel mechanism driving older adulthood health disparities.
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Light-harvesting chlorophyll a/b binding proteins are encoded by nucleus genes and widely involve in capturing light energy, transferring energy, and responding to various stresses. However, their roles in wheat photosynthesis and stress tolerance are largely unknown. Here, Triticum aestivumlight-harvesting chlorophyll a/b binding protein TaLhc2 was identified. It showed subcellular localization in chloroplast, contained light responsive cis-elements, and highly expressed in green tissues and down-regulated by multiple stresses. TaLhc2 promoted the colonization of hemi-biotrophic pathogen; further analysis showed that TaLhc2 strengthened BAX-induced cell death, enhanced the ROS accumulation, and up-regulated pathogenesis-related genes; those results suggested that TaLhc2 has adverse influence on host immunity and function as a susceptible gene, thus host decreased its expression when faced with pathogen infection. RT-qPCR results showed that TaLhc2 was down-regulated by drought and salt stresses, while TaLhc2 improved the ROS accumulation under the two stresses, suggesting TaLhc2 may participate in wheat responding to abiotic stress. Additionally, TaLhc2 can increase the content of total chlorophyll and carotenoid by 1.3 % and 2.9 %, increase the net photosynthetic rate by 18 %, thus promote plant photosynthesis. Conclusively, we preliminarily deciphered the function of TaLhc2 in biotic/abiotic stresses and photosynthesis, which laid foundation for its usage in wheat breeding.
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Proteínas de Plantas , Triticum , Triticum/metabolismo , Clorofila A/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Espécies Reativas de Oxigênio/metabolismo , Plantas Geneticamente Modificadas/genética , Fotossíntese , Estresse Fisiológico/genética , Regulação da Expressão Gênica de PlantasRESUMO
Unknown functional domain (DUF) proteins constitute a large number of functionally uncharacterized protein families in eukaryotes. DUF724s play crucial roles in plants. However, the insight understanding of wheat TaDUF724s is currently lacking. To explore the possible function of TaDUF724s in wheat growth and development and stress response, the family members were systematically identified and characterized. In total, 14 TaDUF724s were detected from a wheat reference genome; they are unevenly distributed across the 11 chromosomes, and, according to chromosome location, they were named TaDUF724-1 to TaDUF724-14. Evolution analysis revealed that TaDUF724s were under negative selection, and fragment replication was the main reason for family expansion. All TaDUF724s are unstable proteins; most TaDUF724s are acidic and hydrophilic. They were predicted to be located in the nucleus and chloroplast. The promoter regions of TaDUF724s were enriched with the cis-elements functionally associated with growth and development, as well as being hormone-responsive. Expression profiling showed that TaDUF724-9 was highly expressed in seedings, roots, leaves, stems, spikes and grains, and strongly expressed throughout the whole growth period. The 12 TaDUF724 were post-transcription regulated by 12 wheat MicroRNA (miRNA) through cleavage and translation. RT-qPCR showed that six TaDUF724s were regulated by biological and abiotic stresses. Conclusively, TaDUF724s were systematically analyzed using bioinformatics methods, which laid a theoretical foundation for clarifying the function of TaDUF724s in wheat.
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Genoma de Planta , Triticum , Triticum/metabolismo , Família Multigênica , Biologia Computacional/métodos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Filogenia , Perfilação da Expressão Gênica/métodosRESUMO
Collagen-based hydrogels have a significant impact on wound healing, but they suffer from structural instability and bacterial invasion in infected wounds. Here, electrospun nanofibers of esterified hyaluronan (HA-Bn/T) are developed to immobilize the hydrophobic antibacterial drug tetracycline by π-π stacking interaction. Dopamine-modified hyaluronan and HA-Bn/T are employed simultaneously to stabilize the structure of collagen-based hydrogel by chemically interweaving the collagen fibril network and decreasing the rate of collagen degradation. This renders it injectable for in situ gelation, with suitable skin adhesion properties and long-lasting drug release capability. This hybridized interwoven hydrogel promotes the proliferation and migration of L929 cells and vascularization in vitro. It presents satisfactory antibacterial ability against Staphylococcus aureus and Escherichia coli. The structure also retains the functional protein environment provided by collagen fiber, inhibits the bacterial environment of infected wounds, and modulates local inflammation, resulting in neovascularization, collagen deposition, and partial follicular regeneration. This strategy offers a new solution for infected wound healing.
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Ácido Hialurônico , Hidrogéis , Hidrogéis/química , Ácido Hialurônico/química , Adesivos , Cicatrização , Colágeno/farmacologia , Tetraciclina , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias , Escherichia coliRESUMO
Cutaneous wound healing is a complex process that strives to re-establish the original structure and functions of the skin. With the development of electrospinning technology, nanofibrous membrane biomaterials have emerged as promising pro-regenerative strategies for recapitulating the structure and composition of the natural extracellular matrix (ECM). Herein, a nanofibrous membrane wound dressing material based on recombinant human collagen type III (rhCol III) crosslinked by EDC/NHS (rhCol III EN NF), which incorporated multiple Gly-Glu-Lys (GEK) and Gly-Leu-Ser-Gly-Glu-Arg (GLSGER) integrin receptors, has been developed utilizing green electrospinning technology. The rhCol III EN NF exhibited excellent flexibility, mechanical properties and water absorption. Amino acid analysis showed that rhCol III EN NF retained integrin receptor-associated amino acids to mediate cell activities and then expedite wound healing. Subsequent in vitro experiments confirmed that the rhCol III EN NF effectively promotes cell adhesion, proliferation and migration. On a mouse full-thickness wound model, rhCol III EN NF dressings expedited wound closure and greatly improved collagen deposition, recovering dermal and epidermal structures as well as skin appendages. Altogether, our research demonstrated that rhCol III EN NF prepared by electrospinning technology could efficiently heal wounds and regenerate skin.
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Colágeno Tipo III , Nanofibras , Camundongos , Animais , Humanos , Nanofibras/química , Cicatrização , Pele , IntegrinasRESUMO
This review examines major bodies of literature, interrelated but usually considered separately, focused on work trajectories and their intersections with family dynamics through the life course. It begins with a consideration of the life course paradigm, which draws attention to the temporal dimensions of human lives, and recently developed analytic techniques that are well-suited to empirical investigation of life course transitions and trajectories over time. The review proceeds to examine empirical research on work career mobility (including both inter- and intra-generational mobility) measured as either trajectories of continuous outcomes or sequences of categorical outcomes, and their long-term consequences for socioeconomic attainment. Work-family trajectories are then addressed, focusing on the impacts of family on work, notably expressed in the motherhood wage penalty, and how family structure and processes affect long-term labor market outcomes. Research documents considerable heterogeneity in work-family dynamics over the life course across social groups with unequal resources. The review concludes with an assessment of the interplay of work and family trajectories studied longitudinally and makes recommendations for future research. It is argued that while extant studies of the work-family interface are compatible with, and sometimes deliberately reflect, a life course perspective, these bodies of research would benefit from more fully incorporating the life course principles of "agency" and "time and place".