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In recent years, wide field-of-view imaging technology based on a metasurface has been widely applied. However, works on the reported sub-diffraction metalens with a wide field-of-view indicate that multiple structures are essential to effectively eliminate aberrations, which results in a heavy device thickness and weakens the advantage of an ultra-thin metasurface. To solve this problem, according to the super-oscillation theory and the translational symmetry of quadratic phase, as well as the principle of virtual aperture diaphragm based on wave vector filter, this Letter demonstrates a sub-diffraction metalens combined with a single quadratic metalens and a wave vector filter. Our design not only realizes the super-resolution effects of 0.74 to 0.75 times the diffraction limit in the wide field-of-view of nearly 180° for the first time to our knowledge but also compresses the device thickness to the subwavelength order in principle. The proposed ultra-thin sub-diffraction metalens with a wide field-of-view is expected to be applied in the fields of super-resolution fast scanning imaging, information detection, small target recognition, and so on.
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UVB radiation is known to induce photodamage to the skin, disrupt the skin barrier, elicit cutaneous inflammation, and accelerate the aging process. Agaricus blazei Murill (ABM) is an edible medicinal and nutritional fungus. One of its constituents, Agaricus blazei Murill polysaccharide (ABP), has been reported to exhibit antioxidant, anti-inflammatory, anti-tumor, and immunomodulatory effects, which suggests potential effects that protect against photodamage. In this study, a UVB-induced photodamage HaCaT model was established to investigate the potential reparative effects of ABP and its two constituents (A1 and A2). Firstly, two purified polysaccharides, A1 and A2, were obtained by DEAE-52 cellulose column chromatography, and their physical properties and chemical structures were studied. A1 and A2 exhibited a network-like microstructure, with molecular weights of 1.5 × 104 Da and 6.5 × 104 Da, respectively. The effects of A1 and A2 on cell proliferation, the mitochondrial membrane potential, and inflammatory factors were also explored. The results show that A1 and A2 significantly promoted cell proliferation, enhanced the mitochondrial membrane potential, suppressed the expression of inflammatory factors interleukin-1ß (IL-1ß), interleukin-8 (IL-8), interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α), and increased the relative content of filaggrin (FLG) and aquaporin-3 (AQP3). The down-regulated JAK-STAT signaling pathway was found to play a role in the response to photodamage. These findings underscore the potential of ABP to ameliorate UVB-induced skin damage.
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Agaricus , Proliferação de Células , Proteínas Filagrinas , Células HaCaT , Raios Ultravioleta , Agaricus/química , Humanos , Raios Ultravioleta/efeitos adversos , Proliferação de Células/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Polissacarídeos Fúngicos/farmacologia , Polissacarídeos Fúngicos/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Citocinas/metabolismoRESUMO
Acne is a chronic inflammatory skin disease with a recurring nature that seriously impacts patients' quality of life. Currently, antibiotic resistance has made it less effective in treating acne. However, Paris polyphylla (P. polyphylla) is a valuable medicinal plant with a wide range of chemical components. Of these, P. polyphylla saponins modulate the effects in vivo and in vitro through antibacterial, anti-inflammatory, immunomodulatory, and antioxidant effects. Acne is primarily associated with inflammatory reactions, abnormal sebum function, micro-ecological disorders, hair follicle hyperkeratosis, and, in some patients, immune function. Therefore, the role of P. polyphylla saponins and their values in treating acne is worthy of investigation. Overall, this review first describes the distribution and characteristics of P. polyphylla and the pathogenesis of acne. Then, the potential mechanisms of P. polyphylla saponins in treating acne are listed in detail (reduction in the inflammatory response, antibacterial action, modulation of immune response and antioxidant effects, etc.). In addition, a brief description of the chemical composition of P. polyphylla saponins and its available extraction methods are described. We hope this review can serve as a quick and detailed reference for future studies on their potential acne treatment.
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Acne Vulgar , Antibacterianos , Anti-Inflamatórios , Antioxidantes , Saponinas , Humanos , Acne Vulgar/tratamento farmacológico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/química , Saponinas/farmacologia , Saponinas/química , Saponinas/uso terapêutico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Animais , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Fatores Imunológicos/química , Agentes de Imunomodulação/farmacologia , Agentes de Imunomodulação/química , Agentes de Imunomodulação/uso terapêutico , Agentes de Imunomodulação/isolamento & purificação , Melanthiaceae/química , Liliaceae/químicaRESUMO
High-sensitivity, reproducible, and low-cost substrate has been a major obstacle for practical sensing application of surface-enhancement Raman scattering (SERS). In this work, we report a type of simple SERS substrate which is composed of metal-insulator-metal (MIM) structure of Ag nanoisland (AgNI)-SiO2-Ag film (AgF). The substrates are fabricated by only evaporation and sputtering processes, which are simple, fast and low-cost. By combining the hotspots and interference-enhanced effects in AgNIs and the plasmonic cavity (SiO2) between AgNIs and AgF, the proposed SERS substrate shows an enhancement factor (EF) of 1.83 × 108 with limit of detection (LOD) down to 10-17â mol/L for rhodamine 6â G (R6G) molecules. The EFs are â¼18 times higher than that of conventional AgNIs without MIM structure. In addition, the MIM structure shows excellent reproducibility with relative standard deviation (RSD) less than 9%. The proposed SERS substrate is fabricated only with evaporation and sputtering technique and the conventionally used lithographic methods or chemical synthesis are not required. This work provides a simple way to fabricate ultrasensitive and reproducible SERS substrates which show great promise for developing various biochemical sensors with SERS.
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UVB radiation can induce oxidative stress and inflammatory response in human epidermal cells. We establish a UVB-induced damage model of human immortalized epidermal keratinocytes (HaCaT) to explore the protective and reparative effects of Laminaria japonica on UVB-damaged epidermal inflammation after fermentation by white Ganoderma lucidum (Curtis) P. Karst and Saccharomyces cerevisiae. Compared with unfermented Laminaria japonica, fermented Laminaria japonica possesses stronger in vitro free radical scavenging ability. Laminaria japonica white Ganoderma lucidum fermentation broth (LJ-G) and Laminaria japonica rice wine yeast fermentation broth (LJ-Y) can more effectively remove excess reactive oxygen species (ROS) in cells and increase the content of the intracellular antioxidant enzymes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO-1). In addition, fermented Laminaria japonica effectively reduces the content of pro-inflammatory factors ILs, TNF-α and MMP-9 secreted by cells. The molecular research results show that fermented Laminaria japonica activates the Nrf2 signaling pathway, increases the synthesis of antioxidant enzymes, inhibits the gene expression levels of pro-inflammatory factors, and alleviates cellular oxidative stress and inflammatory response caused by UVB radiation. Based on the above results, we conclude that fermented Laminaria japonica has stronger antioxidant and anti-inflammatory activity than unfermented Laminaria japonica, possesses good safety, and can be developed and used as a functional inflammation reliever. Fermented Laminaria japonica polysaccharide has a more slender morphological structure and more rockulose, with better moisturizing and rheological properties.
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Laminaria , Vinho , Humanos , Laminaria/química , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Heme Oxigenase-1/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fermentação , Fator de Necrose Tumoral alfa/metabolismo , Saccharomyces cerevisiae/metabolismo , NAD/metabolismo , NAD/farmacologia , Raios Ultravioleta/efeitos adversos , Estresse Oxidativo , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Quinonas/farmacologiaRESUMO
Opuntia milpa alta polysaccharides (ODP) are bioactive compounds extracted from Opuntia milpa alta and widely used in the treatment of diseases, but the therapeutic mechanism of ODP on inflammatory injury remains unclear. Therefore, this study explores the effects and mechanisms of ODP in lipopolysaccharide (LPS)-induced inflammation of human keratinocytes (HaCaT). In this experiment, ODP was extracted via the water extraction and fermentation methods, respectively. LPS was then used to induce inflammatory damage in HaCaT cells, and the stimulated cells were treated with different concentrations of ODP. Cell viability was detected by MTT assay, and the concentrations of COX-2, iNOS, IL-6, IL-8, IL-10 and TNF-α were determined by enzyme-linked immunosorbent assay (ELISA). Changes in inflammatory cytokines and related mRNA expression were observed to assess LPS-induced cell damage. In the experiment, it was found that the LPS stimulation of HaCaT cells can induce cellular inflammatory response, reduce cell viability, increase cell apoptosis and increase the expression of COX-2, iNOS, IL-6, IL-8, IL-10 and TNF-α. However, the experimental data shows that ODP can reverse the above results by increasing cell viability, inhibiting cell apoptosis, reducing the expression of the above genes and inactivating antioxidant pathways, which revealed the specific mechanism of ODP repairing LPS-induced inflammatory damage to Hacat cell. In addition, The experimental results showed that fermentation could improve the anti-inflammatory effect of ODP. In conclusion, our experimental results indicate that ODP fermented by lactic acid bacteria can be used as an anti-inflammatory agent.
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Lactobacillales , Opuntia , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2/metabolismo , Células HaCaT , Humanos , Interleucina-10/metabolismo , Interleucina-10/farmacologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Queratinócitos , Lactobacillales/metabolismo , Lipopolissacarídeos/farmacologia , Opuntia/metabolismo , Polissacarídeos/farmacologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Based on the delicate interference behavior of light in the far field, the optical super-oscillatory phenomenon has been successfully applied in non-invasive sub-diffraction focusing and super-resolution imaging in recent years. However, the optical super-oscillatory field is particularly sensitive to the change of incident angle, leading to a limited field of view for super-resolution imaging. In this paper, a super-oscillatory metasurface doublet is proposed to achieve far-field sub-diffraction focusing with an incident angle of up to 25°. The constructed doublet, consisting of high-aspect-ratio rectangular nanopillars with high efficiency, is further demonstrated through a full-wave simulation, and the numerical results indicate that the sub-diffraction foci with about 0.75 times of the diffraction limit is achieved for different incident angles. The proposed super-oscillatory metasurface doublet may find intriguing applications in label-free super-resolution microscopy and optical precise fabrication.
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This research evaluated the clinical efficacy of three-wings rib plate in the treatment of multiple rib fractures and flail chest with mechanical analysis and clinical verification. The model of rib and three-wings rib plate was reconstructed. The contact simulation with pretension stress was applied to the plate's fixation, and it was found that the bearable stress of the rib fractures after fixation increased from the result which indicated a good fixation efficacy of the plate. Clinical data of 53 cases of rib fractures and flail chest treated with three-wings rib plate in Shanghai Pudong Hospital of Fudan University were retrospectively analyzed. After the operation, the pain of the patients was relieved. Postoperative CT reconstruction of the chest showed good restoration of the rib fractures, which verified the clinical efficacy of three-wings rib plate. The three-wings rib plate showed a high value in clinical use for treatment of rib fractures.
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Tórax Fundido , Fraturas das Costelas , China , Tórax Fundido/cirurgia , Fixação Interna de Fraturas , Humanos , Estudos Retrospectivos , Fraturas das Costelas/cirurgia , CostelasRESUMO
Due to the ability to tightly confine electromagnetic energy, plasmonic nanoantennas have been widely studied for surface-enhanced infrared absorption (SEIRA) spectroscopy, surface-enhanced Raman spectroscopy as well as refractive index sensing. However, most of the nanoantennas are limited by narrow resonant band and it is rather challenging to detect multiple molecular fingerprints. In this work, we report dual and triple- resonant pad-rod plasmonic nanoantennas which are nanorods with large pads at their ends placed above gold (Au) mirror separated by a spacer layer. By adjusting the geometries, the nanoantennas have demonstrated dual and triple resonant bands enabling detection of molecular fingerprints at different wavelength. The calculated maximum SEIRA enhancement factor is around 1.8 × 106, which is among the highest reported so far. The pad-rod plasmonic nanoantennas have been used for the detection of molecules of polymethyl methacrylate (PMMA) by SEIRA and fingerprints of C=O and C-H bands are clearly identified. This work has shown that the multiple-resonant pad-rod plasmonic nanoantennas are promising for chemical and biomolecular sensing by the detection of vibrational fingerprints with SEIRA.
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Mature microRNAs (miRNAs) are small-sized RNAs cleaved from precursor microRNAs (pre-miRNAs) by the RNase Dicer. Various miRNAs play key regulatory roles in tumorigenesis and metastasis, and are therefore potential diagnostic and prognostic cancer biomarkers. However, detecting miRNAs and pre-miRNAs accurately and selectively in living cells remains a major challenge, as the mature miRNA sequence is also present in its pre-miRNA and current sequence probes exhibit poor gene delivery efficiency. Herein, we report a strategy for selectively and accurately detecting miRNA-21 and pre-miRNA-21 in living cells using functional MoS2 nanosheets (NSs) loaded with rationally engineered molecular beacons (MBs). The exfoliated MoS2 nanosheets (NSs) with a mean lateral diameter of 50-70 nm were functionalized with the aptamer AS1411 and polyethylene glycol (MoS2-PEG-AS) to achieve target-cell-specific delivery and to enhance biocompatibility. The large available surface of the MoS2-PEG-AS was loaded with MB probes. The resulting MoS2-PEG-AS/MBs present cancer-cell-targeting ability, good protection properties, good optical stability, and biocompatibility. We demonstrated that the resulting nanoprobes can selectively image miRNA-21 and pre-miRNA-21 in various cell lines by facilitating enhanced fluorescence in the presence of miRNA-21 and pre-miRNA-21. Thus, these MoS2-PEG-AS/MBs are potentially a tool to discriminate between intracellular miRNA and pre-miRNA at different expression levels. Graphical abstract.
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Dissulfetos/química , MicroRNAs/análise , Molibdênio/química , Nanoestruturas/química , Aptâmeros de Nucleotídeos/química , Materiais Biocompatíveis , Fluorescência , Humanos , Células MCF-7 , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Oligodesoxirribonucleotídeos/química , Polietilenoglicóis/químicaRESUMO
To meet the need for high-throughput immunoassays, many multiplex fluorescent immunoassays have been proposed. Most of them need different kinds of fluorescent label indicators during the test. In this work, a novel indirect ELISA-inspired dual-channel fluorescent immunoassay based on 3-mercaptopropionic acid capped CdTe/ZnS quantum dots (QDs) was constructed. The ELISA wells were coated with two kinds of antigen-QD complex. When the primary antibodies were present in a sample, they mediated the binding of a secondary antibody-DNA-gold nanoparticle complex to the antigen-QD complex. Then the gold nanoparticles quenched the fluorescence of the QDs and a decrease in fluorescence intensity was observed. Thus, the amount of primary antibody could be estimated from the decrease of fluorescence intensity. Owing to the wide absorption range and the relatively narrow emission band of the QDs, the dual-channel fluorescent immunoassay system could work at the same excitation wavelength and the emission wavelengths of each channel had no interference. As a result, two different kinds of primary antibody could be detected at the same time in one ELISA well, which simplified the operation and greatly improved the efficiency. Besides, only one type of secondary antibody needs to be added to the prepared microtiter plates, which further simplified the operation during the detection procedure. This dual-channel fluorescent immunoassay system will provide new insights into high-throughput immunodetection. Graphical abstract.
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Compostos de Cádmio/química , Ensaio de Imunoadsorção Enzimática/métodos , Imunofluorescência/métodos , Pontos Quânticos , Sulfetos/química , Telúrio/química , Compostos de Zinco/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de TransmissãoRESUMO
The effects of water-extractable arabinoxylans (WEAXs) with different molecular weights on the physicochemical properties and structure of wheat gluten were studied, a transition between ß-turns in ß-leaves in the structure of gluten has been demonstrated by Fourier transform infrared spectroscopy when WEAX samples were added. The ratio of weakly hydrogen-bonded ß-sheets to strongly hydrogen-bonded ß-sheets tended to decrease with increasing WEAX content. FT-Raman analysis demonstrated other changes in the structure of gluten concerning ß-structures, the conformation of the disulfide bridges, and aromatic amino acid environments; these changes were dependent on the molecular weight of the WEAX. Native WEAXs of different molecular weights that are present as discrete fragments of the cell wall have had a negative effect on the properties of gluten. However, low molecular weight WEAX has helped gluten maintain the left-left conformation of its disulfide bonds. In addition, the gluten elasticity was reduced by the native WEAX to make it softer, but the WEAX low molecular weight impeded this process and improved the gluten network.
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BACKGROUND: Heat stress is a severe environmental stress that affects plant growth and reduces yield. Bax inhibitor-1 (BI-1) is a cytoprotective protein that is involved in the response to biotic and abiotic stresses. The Arabidopsis (Arabidopsis thaliana) BI-1 mutants atbi1-1 and atbi1-2 are hypersensitive to heat stress, and AtBI-1 overexpression rescues thermotolerance deficiency in atbi1 plants. Nevertheless, the mechanism of BI-1 in plant thermotolerance is still unclear. RESULTS: We identified a wheat (Triticum aestivum L.) BI-1 gene, TaBI-1.1, which was highly upregulated in an RNA sequencing (RNA-seq) analysis of heat-treated wheat. The upregulation of TaBI-1.1 under heat stress was further demonstrated by real time quantitative PCR (qRT-PCR) and ß-glucuronidase (GUS) staining. Compared with the wild type Col-0, the atbi1-2 mutant is hypersensitive to heat stress, and constitutive expression of TaBI-1.1 in atbi1-2 (35S::TaBI-1.1/ atbi1-2) rescued the deficiency of atbi1-2 under heat stress. Furthermore, we identified TaFKBP62 as a TaBI-1.1-interacting protein that co-localized with TaBI-1.1 on the endoplasmic reticulum (ER) membrane and enhanced heat stress tolerance. Additionally, HSFA2, HSFB1, ROF1, HSP17.4B, HSP17.6A, HSP17.8, HSP70B, and HSP90.1 expression levels were suppressed in atbi1-2 plants under heat stress. In contrast, 35S::TaBI-1.1/atbi1-2 relieved the inhibitory effect of AtBI-1 loss of function. CONCLUSIONS: TaBI-1.1 interacted with TaFKBP62 and co-localized with TaFKBP62 on the ER membrane. Both TaBI-1.1 and AtBI-1 regulated the expression of heat-responsive genes and were conserved in plant thermotolerance.
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Resposta ao Choque Térmico/fisiologia , Proteínas de Plantas/genética , Triticum/fisiologia , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Retículo Endoplasmático/metabolismo , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico/genética , Membranas Intracelulares/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Domínios e Motivos de Interação entre Proteínas , Triticum/genética , Regulação para CimaRESUMO
BACKGROUND: The calcineurin B-like protein (CBL)-interacting protein kinase (CIPK) signaling pathway responds to various abiotic stresses in plants. RESULTS: Wheat CIPK23, isolated from wheat drought transcriptome data set, was induced by multiple abiotic stresses, including drought, salt, and abscisic acid (ABA). Compared with wild-type plants, TaCIPK23-overexpression wheat and Arabidopsis showed an higher survival rate under drought conditions with enhanced germination rate, developed root system, increased accumulation of osmolytes, and reduced water loss rate. Over-expression of TaCIPK23 rendered transgenic plants ABA sensitivity, as evidenced by delayed seed germination and the induction of stomatal closure. Consistent with the ABA-sensitive phenotype, the expression level of drought- and ABA-responsive genes were increased under drought conditions in the transgenic plants. In addition, using yeast two-hybrid system, pull-down and bimolecular fluorescence complementation (BiFc) assays, TaCIPK23 was found to interact with TaCBL1 on the plasma membrane. CONCLUSIONS: These results suggest that TaCIPK23 plays important roles in ABA and drought stress responses, and mediates crosstalk between the ABA signaling pathway and drought stress responses in wheat.
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Ácido Abscísico/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais , Triticum/enzimologia , Arabidopsis/genética , Arabidopsis/fisiologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Secas , Genes Reporter , Germinação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Plântula/enzimologia , Plântula/genética , Plântula/fisiologia , Sementes/enzimologia , Sementes/genética , Sementes/fisiologia , Cloreto de Sódio/metabolismo , Estresse Fisiológico , Triticum/genética , Triticum/fisiologia , Técnicas do Sistema de Duplo-HíbridoRESUMO
BACKGROUND: Abiotic stress severely influences plant growth and development. MYB transcription factors (TFs), which compose one of the largest TF families, play an important role in abiotic stress responses. RESULT: We identified 139 soybean MYB-related genes; these genes were divided into six groups based on their conserved domain and were distributed among 20 chromosomes (Chrs). Quantitative real-time PCR (qRT-PCR) indicated that GmMYB118 highly responsive to drought, salt and high temperature stress; thus, this gene was selected for further analysis. Subcellular localization revealed that the GmMYB118 protein located in the nucleus. Ectopic expression (EX) of GmMYB118 increased tolerance to drought and salt stress and regulated the expression of several stress-associated genes in transgenic Arabidopsis plants. Similarly, GmMYB118-overexpressing (OE) soybean plants generated via Agrobacterium rhizogenes (A. rhizogenes)-mediated transformation of the hairy roots showed improved drought and salt tolerance. Furthermore, compared with the control (CK) plants, the clustered, regularly interspaced, short palindromic repeat (CRISPR)-transformed plants exhibited reduced drought and salt tolerance. The contents of proline and chlorophyll in the OE plants were significantly greater than those in the CK plants, whose contents were greater than those in the CRISPR plants under drought and salt stress conditions. In contrast, the reactive oxygen species (ROS) and malondialdehyde (MDA) contents were significantly lower in the OE plants than in the CK plants, whose contents were lower than those in the CRISPR plants under stress conditions. CONCLUSIONS: These results indicated that GmMYB118 could improve tolerance to drought and salt stress by promoting expression of stress-associated genes and regulating osmotic and oxidizing substances to maintain cell homeostasis.
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Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Agrobacterium/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Desidratação , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Raízes de Plantas/microbiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Estresse Salino , Glycine max/genética , Glycine max/metabolismo , Glycine max/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologiaRESUMO
Abiotic stresses restrict the growth and yield of crops. Plants have developed a number of regulatory mechanisms to respond to these stresses. WRKY transcription factors (TFs) are plant-specific transcription factors that play essential roles in multiple plant processes, including abiotic stress response. At present, little information regarding drought-related WRKY genes in maize is available. In this study, we identified a WRKY transcription factor gene from maize, named ZmWRKY40. ZmWRKY40 is a member of WRKY group II, localized in the nucleus of mesophyll protoplasts. Several stress-related transcriptional regulatory elements existed in the promoter region of ZmWRKY40. ZmWRKY40 was induced by drought, high salinity, high temperature, and abscisic acid (ABA). ZmWRKY40 could rapidly respond to drought with peak levels (more than 10-fold) at 1 h after treatment. Overexpression of ZmWRKY40 improved drought tolerance in transgenic Arabidopsis by regulating stress-related genes, and the reactive oxygen species (ROS) content in transgenic lines was reduced by enhancing the activities of peroxide dismutase (POD) and catalase (CAT) under drought stress. According to the results, the present study may provide a candidate gene involved in the drought stress response and a theoretical basis to understand the mechanisms of ZmWRKY40 in response to abiotic stresses in maize.
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Arabidopsis/crescimento & desenvolvimento , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Núcleo Celular/metabolismo , Secas , Evolução Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Regiões Promotoras Genéticas , Protoplastos/metabolismo , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
WRKY transcription factors constitute one of the largest transcription factor families in plants, and play crucial roles in plant growth and development, defense regulation and stress responses. However, knowledge about this family in maize is limited. In the present study, we identified a drought-induced WRKY gene, ZmWRKY106, based on the maize drought de novo transcriptome sequencing data. ZmWRKY106 was identified as part of the WRKYII group, and a phylogenetic tree analysis showed that ZmWRKY106 was closer to OsWRKY13. The subcellular localization of ZmWRKY106 was only observed in the nucleus. The promoter region of ZmWRKY106 included the C-repeat/dehydration responsive element (DRE), low-temperature responsive element (LTR), MBS, and TCA-elements, which possibly participate in drought, cold, and salicylic acid (SA) stress responses. The expression of ZmWRKY106 was induced significantly by drought, high temperature, and exogenous abscisic acid (ABA), but was weakly induced by salt. Overexpression of ZmWRKY106 improved the tolerance to drought and heat in transgenic Arabidopsis by regulating stress-related genes through the ABA-signaling pathway, and the reactive oxygen species (ROS) content in transgenic lines was reduced by enhancing the activities of superoxide dismutase (SOD), peroxide dismutase (POD), and catalase (CAT) under drought stress. This suggested that ZmWRKY106 was involved in multiple abiotic stress response pathways and acted as a positive factor under drought and heat stress.
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Adaptação Biológica , Secas , Resposta ao Choque Térmico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/genética , Zea mays/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Fenótipo , Filogenia , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Transporte Proteico , Espécies Reativas de Oxigênio/metabolismo , Elementos de Resposta , Estresse Fisiológico , Fatores de Transcrição/química , Transcriptoma , Zea mays/classificaçãoRESUMO
Interference lithography based on surface plasmon polaritons has been proven to break the diffraction limit and deliver the high imaging resolution. However, most previously reported studies suffer from the inflexible pattern pitch for a certain structure ascribed to fixed excitation mode, which limits the applications in micro-/nano- fabrications. In this work, the large area deep subwavelength interference lithography with tunable pattern period based on bulk plasmon polaritons (BPPs) is proposed. By simply tuning the incident angle, the spatial frequencies of the selected BPPs modes squeezed through hyperbolic metamaterial changes correspondingly. As a result, the pitch of the interference pattern is continuously altered. The results demonstrate that one-dimensional and two-dimensional periodic patterns with pitch resolution ranging from 45 nm (~λ/10) to 115 nm (~λ/4) can be generated under 436 nm illumination. Additionally, the general method of designing such an interference lithography system is also discussed, which can be used for nanoscale fabrication in this fashion.
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Plasmonic lens imaging with some resolution enhancement methods are investigated in this paper, mainly by physical modeling and numerical simulations. The imaging model is based on the refined optical transfer function with extra reflection in imaging space and measured in variant magnetic and electric field components. The influences of structured light illumination and mask patterns' modifications are considered as well. As experimental demonstrations, L-shaped slits pattern with a half-pitch of 60 nm is successfully imaged with 50 nm air distance, by using plasmonic cavity lens lithography and off-axis illumination with 365 nm wavelength light. This study is believed to provide the model and methods for the design of high resolution plasmonic lens employed in nano lithography and optical storage etc.
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In this paper, we report the formation of extremely sharp (Quality factor Q~ + ∞) FR in a single layer of dielectric nanorods with perturbed periodicity. The interference between the broadband Fabry-Perot (F-P) resonance and defect induced dark mode results in refractive index sensitivity (S) of 1312.75 nm/RIU and figure of merit (FOM) of 500, offering an excellent platform for biological sensing and detection.