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Innate antiviral immunity deteriorates with aging but how this occurs is not entirely clear. Here we identified SIRT1-mediated DNA-binding domain (DBD) deacetylation as a critical step for IRF3/7 activation that is inhibited during aging. Viral-stimulated IRF3 underwent liquid-liquid phase separation (LLPS) with interferon (IFN)-stimulated response element DNA and compartmentalized IRF7 in the nucleus, thereby stimulating type I IFN (IFN-I) expression. SIRT1 deficiency resulted in IRF3/IRF7 hyperacetylation in the DBD, which inhibited LLPS and innate immunity, resulting in increased viral load and mortality in mice. By developing a genetic code expansion orthogonal system, we demonstrated the presence of an acetyl moiety at specific IRF3/IRF7 DBD site/s abolish IRF3/IRF7 LLPS and IFN-I induction. SIRT1 agonists rescued SIRT1 activity in aged mice, restored IFN signaling and thus antagonized viral replication. These findings not only identify a mechanism by which SIRT1 regulates IFN production by affecting IRF3/IRF7 LLPS, but also provide information on the drivers of innate immunosenescence.
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Antivirais , Sirtuína 1 , Animais , Imunidade Inata , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Camundongos , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Replicação ViralRESUMO
Chiral perovskites play a pivotal role in spintronics and optoelectronic systems attributed to their chiral-induced spin selectivity (CISS) effect. Specifically, they allow for spin-polarized charge transport in spin light-emitting diodes (LEDs), yielding circularly polarized electroluminescence at room temperature without external magnetic fields. However, chiral lead bromide-based perovskites have yet to achieve high-performance green emissive spin-LEDs, owing to limited CISS effects and charge transport. Herein, we employ dimensional regulation and Sn2+-doping to optimize chiral bromide-based perovskite architecture for green emissive spin-LEDs. The optimized (PEA)x(S/R-PRDA)2-xSn0.1Pb0.9Br4 chiral perovskite film exhibits an enhanced CISS effect, higher hole mobility, and better energy level alignment with the emissive layer. These improvements allow us to fabricate green emissive spin-LEDs with an external quantum efficiency (EQE) of 5.7% and an asymmetry factor |gCP-EL| of 1.1 × 10-3. This work highlights the importance of tailored perovskite architectures and doping strategies in advancing spintronics for optoelectronic applications.
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Heat stress (HS) adversely impacts plant growth, development and grain yield. Heat shock factors (Hsf), especially HsfA2 subclass, play a pivotal role in the transcriptional regulation of genes in response to HS. In this study, the coding sequence of maize ZmHsf17 was cloned. ZmHsf17 contains conserved domains: DNA binding, oligomerization and transcriptional activation. The protein was nuclear localized and had transcription activation activity. Yeast two hybrid and split luciferase complementary assays confirmed the interaction of ZmHsf17 with members of the maize HsfA2 subclass. Overexpression of ZmHsf17 in maize significantly increased chlorophyll content and net photosynthesis rate of maize leaves, and enhanced the stability of cellular membranes. Through integrative analysis of ChIP-seq and RNA-seq datasets, ZmPAH1, encoding phosphatidic acid phosphohydrolase of lipid metabolic pathways, was identified as a target gene of ZmHsf17. The promoter fragment of ZmPAH1 was bound by ZmHsf17 in protein-DNA interaction experiments in vivo and in vitro. Lipidomic data also indicates that the overexpression of ZmHsf17 increased levels of some critical membrane lipid components of maize leaves under HS. This research provides new insights into the role of the ZmHsf17-ZmPAH1 module in regulating thermotolerance in maize.
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pH sensing is essential in various fields including healthcare, environmental monitoring, food safety, and agriculture. In this Letter, we propose a method for a wide-range pH measurement based on the direct response of liquid crystal (LC) to pH variations via the whispering gallery mode (WGM). The liquid crystal 4-cyano-4'-pentylbiphenyl (5CB) is selected for its excellent optoelectronic properties and the birefringence of 5CB microdroplets serving as spherical resonators. This sensor achieves wide-range pH sensing without any intermediaries. Polarized optical microscopy (POM) and WGM provide a qualitative morphological analysis and accurate quantitative spectral measurements. Under alkaline conditions (pH 7.6 to 13.3), POM images of 5CB microdroplets show a complete transition from bipolar to radial structures, with an average sensitivity of 1.78â nm/pH of redshift in WGM spectra. In acidic conditions (pH 6.65 to 1.5), structural changes observed by POM are minor, with a sensitivity of 1.06â nm/pH of blueshift in WGM spectra. This difference is attributed to the varying refractive indices of HCl and NaOH solutions. This method offers a reference for theoretical studies on pH and LC interactions and holds promise for the development of LC-based pH sensors.
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Gallium ion (Ga+ ) beam damage induced indium (In) precipitation in indium gallium arsenide (InGaAs)/indium aluminium arsenide (InAlAs) multiple quantum wells and its corresponding evolution under electron beam irradiation was investigated by valence electron energy loss spectroscopy (VEELS) and high-angle annular dark-field imaging (HAADF) in scanning transmission electron microscopy (STEM). Compared with argon ion milling for sample preparation, the heavier projectiles of Ga+ ions pose a risk to trigger In formation in the form of tiny metallic In clusters. These are shown to be sensitive to electron irradiation and can increase in number and size under the electron beam, deteriorating the structure. Our finding reveals the potential risk of formation of In clusters during focused ion beam (FIB) preparation of InGaAs/InAlAs quantum well samples and their subsequent growth under STEM-HAADF imaging, where initially invisible In clusters of a few atoms can move and swell during electron beam exposure.
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Sequentially timed all-optical mapping photography is one of the main emerging ultra-fast detection technologies that can be widely applicable to ultra-fast detection at the picosecond level in fields such as materials and life sciences. We propose a new optical structure for an all-optical spatial mapping module that can control the optical field of two-dimensional imaging while improving spectral resolution and detector sensor utilization. The model of optical parameters based on geometrical optics theory for the given structure has been established, and the theoretical analysis of the inter-frame energy crosstalk caused by incident beam spot width, chromatic aberration, and main errors of the periscope array has been conducted. The optical design of the two-dimensional (2D) all-optical spatial mapping module was finally completed using ZEMAX OpticStudio 2018 software. The results show that our optical module can realize targets of 16 frames and 1.25 nm spectral resolution.
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Lead halide perovskite nanocrystals (LHP NCs) are regarded as promising emitters for next-generation ultrahigh-definition displays due to their high color purity and wide color gamut. Recently, the external quantum efficiency (EQE) of LHP NC based light-emitting diodes (PNC LEDs) has been rapidly improved to a level required by practical applications. However, the poor operational stability of the device, caused by halide ion migration at the grain boundary of LHP NC thin films, remains a great challenge. Herein, we report a resurfacing strategy via pseudohalogen ions to mitigate detrimental halide ion migration, aiming to stabilize PNC LEDs. We employ a thiocyanate solution processed post-treatment method to efficiently resurface CsPbBr3 NCs and demonstrate that the thiocyanate ions can effectively inhibit bromide ion migration in LHP NC thin films. Owing to thiocyanate resurfacing, we fabricated LEDs with a high EQE of 17.3%, a maximum brightness of 48000 cd m-2, and an excellent operation half-life time.
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Glucose transporters GLUT1 belong to the major facilitator superfamily and are essential to human glucose uptake. The overexpression of GLUT1 in tumor cells designates it as a pivotal target for glycoconjugate anticancer drugs. However, the interaction mechanism of glycoconjugate drugs with GLUT1 remains largely unknown. Here, we employed all-atom molecular dynamics simulations, coupled to steered and umbrella sampling techniques, to examine the thermodynamics governing the transport of glucose and two glycoconjugate drugs (i.e., 6-D-glucose-conjugated methane sulfonate and 6-D-glucose chlorambucil) by GLUT1. We characterized the specific interactions between GLUT1 and substrates at different transport stages, including substrate recognition, transport, and releasing, and identified the key residues involved in these procedures. Importantly, our results described, for the first time, the free energy profiles of GLUT1-transporting glycoconjugate drugs, and demonstrated that H160 and W388 served as important gates to regulate their transport via GLUT1. These findings provide novel atomic-scale insights for understanding the transport mechanism of GLUT1, facilitating the discovery and rational design of GLUT1-targeted anticancer drugs.
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Transportador de Glucose Tipo 1 , Glicoconjugados , Simulação de Dinâmica Molecular , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 1/química , Glicoconjugados/metabolismo , Glicoconjugados/química , Humanos , Glucose/metabolismo , Transporte Biológico , TermodinâmicaRESUMO
Drought stress can seriously affect the yield and quality of wheat (Triticum aestivum). So far, although few wheat heat shock transcription factors (Hsfs) have been found to be involved in the stress response, the biological functions of them, especially the members of the HsfC (heat shock transcription factor C) subclass, remain largely unknown. Here, we identified a class C encoding gene, TaHsfC3-4, based on our previous omics data and analyzed its biological function in transgenic plants. TaHsfC3-4 encodes a protein containing 274 amino acids and shows the basic characteristics of the HsfC class. Gene expression profiles revealed that TaHsfC3-4 was constitutively expressed in many tissues of wheat and was induced during seed maturation. TaHsfC3-4 could be upregulated by PEG and abscisic acid (ABA), suggesting that this Hsf may be involved in the regulation pathway depending on ABA in drought resistance. Further results represented that TaHsfC3-4 was localized in the nucleus but had no transcriptional activation activity. Notably, overexpression of TaHsfC3-4 in Arabidopsis thaliana pyr1pyl1pyl2pyl4 (pyr1pyl124) quadruple mutant plants complemented the ABA-hyposensitive phenotypes of the quadruple mutant including cotyledon greening, root elongation, seedling growth, and increased tolerance to drought, indicating positive roles of TaHsfC3-4 in the ABA signaling pathway and drought tolerance. Furthermore, we identified TaHsfA2-11 as a TaHsfC3-4-interacting protein by yeast two-hybrid (Y2H) screening. The experimental data show that TaHsfC3-4 can indeed interact with TaHsfA2-11 in vitro and in vivo. Moreover, transgenic Arabidopsis TaHsfA2-11 overexpression lines exhibited enhanced drought tolerance, too. In summary, our study confirmed the role of TaHsfC3-4 in response to drought stress and provided a target locus for marker-assisted selection breeding to improve drought tolerance in wheat.
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Arabidopsis , Resistência à Seca , Regulação para Cima , Triticum/genética , Fatores de Transcrição de Choque Térmico , Ácido Abscísico/farmacologia , Arabidopsis/genética , Interleucina-6RESUMO
A novel, to the best of our knowledge, type of compact pH fiber sensor combined with a hydrogel based on the whispering gallery mode (WGM) is proposed and integrates a liquid crystal (LC) microdroplet in a capillary in a compact structure as small as 180â µm. In the research, the hydrogel performs both as a supporting frame and a responsive material that causes morphological deformation of the LC microdroplet with pH variation. Moreover, a new phenomenon of pH-induced LC refractive index variation is observed and applied in the pH measurement, so that the acid itself can also lead the LC microdroplet structure transition. Thus, the WGM method is applied to detect the composite effect simultaneously to improve the sensing capability. The sensitivity of the sensor in the pH range from 4.55 to 6.86 reaches 3.19â nm/pH. The response time is short, within 60â s. The simple and compact structure of the sensor reduces the cost and enhances the stability, which is of great potential for biomedical pH measurement.
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Cristais Líquidos , Refratometria , Hidrogéis , Concentração de Íons de HidrogênioRESUMO
Hepatocellular carcinoma (HCC) is a fatal malignancy which has insufficient treatment options. Long non-coding RNA (lncRNA) GASAL1 was discovered to be conspicuously up-regulated in HCC. However, the study on the role of GASAL1 in HCC reamins limited. Our study aimed at exploring the role and mechanism of GASAL1 in HCC. RT-qPCR or Western blot was conducted to examine the expression of RNAs or proteins. Functional assays were carried out to investigate the impact of GASAL1, USP10, and PCNA on HCC cells. Mechanism assays were performed to fathom out the relationship among GASAL1, miR-193b-5p, USP10, and PCNA. In vivo assays were also employed to determine the role of GASAL1 in HCC tumor growth and metastases. According to the data collected, GASAL1 displayed a high expression in HCC cells and GASAL1 knockdown led to impeded cell proliferation and migration, as well as tumor progression. A series of mechanism analysis demonstrated GASAL1 could sponge miR-193b-5p to raise the expression of USP10. Moreover, USP10 could induce PCNA deubiquitination to promote HCC cell growth. To conclude, GASAL1 plays an oncogenic role in HCC. GASAL1 could up-regulate USP10 via competitively binding to miR-193b-5p. And USP10 could strengthen cell proliferative and migratory abilities through deubiquitinating PCNA.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Antígeno Nuclear de Célula em Proliferação/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismoRESUMO
High temperature has severely affected plant growth and development, resulting in reduced production of crops worldwide, especially wheat. Alternative splicing (AS), a crucial post-transcriptional regulatory mechanism, is involved in the growth and development of eukaryotes and the adaptation to environmental changes. Previous transcriptome data suggested that heat shock transcription factor (Hsf) TaHsfA2-7 may form different transcripts by AS. However, it remains unclear whether this post-transcriptional regulatory mechanism of TaHsfA2-7 is related to thermotolerance in wheat (Triticum aestivum). Here, we identified a novel splice variant, TaHsfA2-7-AS, which was induced by high temperature and played a positive role in thermotolerance regulation in wheat. Moreover, TaHsfA2-7-AS is predicted to encode a small truncated TaHsfA2-7 isoform, retaining only part of the DNA-binding domain (DBD). TaHsfA2-7-AS is constitutively expressed in various tissues of wheat. Notably, the expression level of TaHsfA2-7-AS is significantly up-regulated by heat shock (HS) during flowering and grain-filling stages in wheat. Further studies showed that TaHsfA2-7-AS was localized in the nucleus but lacked transcriptional activation activity. Ectopic expression of TaHsfA2-7-AS in yeast exhibited improved thermotolerance. Compared to non-transgenic plants, overexpression of TaHsfA2-7-AS in Arabidopsis results in enhanced tolerance to heat stress. Simultaneously, we also found that TaHsfA1 is directly involved in the transcriptional regulation of TaHsfA2-7 and TaHsfA2-7-AS. In summary, our findings demonstrate the function of TaHsfA2-7-AS splicing variant in response to heat stress and establish a link between regulatory mechanisms of AS and the improvement of thermotolerance in wheat.
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Arabidopsis , Termotolerância , Termotolerância/genética , Triticum/metabolismo , Processamento Alternativo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Resposta ao Choque Térmico/genética , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura AltaRESUMO
'Huangguan' pear (Pyrus bretschneideri Rehd) fruit is susceptible to cold, characterized by developing peel browning spots (PBS) during cold storage. Additionally, ethylene pretreatment reduces chilling injury (CI) and inhibits PBS occurrence, but the mechanism of CI remains unclear. Here, we deciphered the dynamic transcriptional changes during the PBS occurrence with and without ethylene pretreatment via time-series transcriptome. We found that ethylene suppressed the cold-signaling gene expression, thereby decreasing the cold sensitivity of the 'Huangguan' fruit. Moreover, the "Yellow" module closely correlated with PBS occurrence was identified via weighted gene co-expression network analysis (WGCNA), and this module was related to plant defense via Gene Ontology (GO) enrichment analysis. Local motif enrichment analysis suggested that the "Yellow" module genes were regulated by ERF and WRKY transcription factors. Functional studies demonstrated that PbWRKY31 has a conserved WRKY domain, lacks transactivation activity, and localizes in the nucleus. PbWRKY31-overexpressed Arabidopsis were hypersensitive to cold, with higher expression levels of cold signaling and defense genes, suggesting that PbWRKY31 participates in regulating plant cold sensitivity. Collectively, our findings provide a comprehensive transcriptional overview of PBS occurrence and elucidate the molecular mechanism by which ethylene reduces the cold sensitivity of 'Huangguan' fruit as well as the potential role of PbWRKY31 in this process.
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Pyrus , Transcriptoma , Pyrus/genética , Pyrus/metabolismo , Etilenos/farmacologia , Etilenos/metabolismo , Perfilação da Expressão Gênica , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Temperatura BaixaRESUMO
Ultra-low sample consumption detection has many applications in molecular biology, bioanalytical chemistry, and medical science. In this Letter, a novel, to the best of our knowledge, simple type of ultra-low sample consumption detection method based on a whispering gallery mode is proposed as a means to realize consecutive detection with a liquid crystal (LC) microdroplet for biochemical molecule detection, using deoxyribonucleic acid (DNA) as a model biomarker. The sensor consists of a 105-µm-core multimode fiber fused with a hollow capillary tube, with the LC microdroplet suspended stably in the testing solution. Its application to the detection of salmon sperm DNA yielded an adjustable measurement range of 3.75-11.25 µg/ml and a sensitivity of 0.33 nm/µg/ml. The test solution required as little as 3 nl of the sample, and the limit of detection was 1.32 µg/ml, which corresponds to the effective detection of as little as 3.96 pg of DNA. This method has great potential for application in the ultra-low sample consumption detection of biochemical molecules.
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Cristais LíquidosRESUMO
OBJECTIVE: Late-life suicide is a vital public health concern. Though gerontological research suggested the young-old and old-old phases were heterogeneous, age differences in the elderly suicide have not been well studied due to the lack of comparable control groups and small samples. The study aimed to examine the age-specific suicidal characteristics and risk factors among the young-old (60-79) and old-old (over 80) elderly. METHODS: Two hundred and forty two suicide decedents and 242 living comparisons were enrolled in a 1:1 matched case-control psychological autopsy study in rural China: 173 young-old and 69 old-old in each group. Suicidal characteristics, demographic characteristics, living arrangements, physical health, mental disorder, and psychosocial factors were collected. We used logistic regression models to assess risk factors of suicide and test for interactions between age and each risk factor. RESULTS: Pesticide suicide was more prevalent among young-old suicides than old-old suicides (56.07% vs. 40.58%, p = 0.029). Non-currently married, unemployment, mental disorder, higher disability in physical activities of daily living, higher hopelessness and higher depressive symptom were significantly associated with suicide among older adults. The effect of poor function in physical activities of daily living on suicide was significantly greater during younger ages (p for interaction = 0.038). CONCLUSIONS: Findings indicated that most suicidal characteristics and risk factors for completed suicide were generally similar among young-old and old-old adults. But poor function in physical activities of daily living predicted increase suicide risk only at younger ages. In addition to common risk factors, age-specific factors should also be noted in suicide prevention. CLINICAL TRIAL REGISTRATION: According to the ICMJE, purely observational studies (those in which the assignment of the medical intervention is not at the discretion of the investigator) will not require registration. Our study was not registered because this is a case-control study. But all procedures of the study were carried out in accordance with the latest version of the Declaration of Helsinki. The study were approved by the Institutional Review Boards of the Central South University, Shandong University, and Guangxi Medical University.
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OBJECTIVES: Physical diseases are well-established risk factor for suicide, particularly among older adults. However, little is known about the underlying mechanism of the association. This study aimed to describe the prevalence of physical diseases and their influences on the elderly in rural China and to examine the underlying mechanisms of the relationship between physical diseases and suicide. METHODS: This matched case-control psychological autopsy study was conducted from June 2014 to September 2015. Consecutive suicide cases (242) among people aged 60 years or above were identified in three Chinese provinces. The suicide cases were 1:1 matched with living comparisons based on age, gender and residential area. Two informants for each participant were interviewed to collect data on their demographic characteristics, the severity index of physical diseases, depressive symptoms, feelings of hopelessness, mental disorders and social support. RESULTS: A significant difference was found between suicide cases and living comparisons regarding the prevalence of physical diseases (83.5% vs 66.5%, p < 0.001) and their severity (11.3 ± 6.2 vs 6.7 ± 5.3, p < 0.001). Independent risks of suicide included the following: not currently married (OR = 2.81, 95% CI = [1.04, 7.62]), mental disorders (OR = 7.18, 95% CI = [1.83, 28.13]), depressive symptoms (OR = 1.15, 95% CI = [1.05, 1.26]) and feelings of hopelessness (OR = 1.51, 95% CI = [1.20, 1.90]). The structural equation model indicated that the relationship between the severity index of physical diseases and suicide was mediated by depressive symptoms, feelings of hopelessness and mental disorders. CONCLUSION: The severity and number of physical diseases were found to be correlated with suicide among the elderly in rural China, after controlling for demographic characteristics. Physical diseases elevate one's suicide risk by increasing depressive symptoms, feelings of hopelessness and mental disorders. Efforts for suicide prevention should be integrated with strategies to treat physical diseases along with psychological interventions.
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Suicídio , Idoso , Autopsia , Estudos de Casos e Controles , China/epidemiologia , Humanos , Fatores de Risco , População Rural , Suicídio/psicologiaRESUMO
Optic pathway glioma (OPG) is a rare brain tumor affecting children, with no standard treatment strategy. This study described the sporadic OPG survival outcomes after surgical treatment and analyzed the role of imaging features and resection status in children receiving different adjuvant treatments. This retrospective study included 165 OPG patients whose clinical information were obtained from the hospital record system. Tumor volume and residual tumor volume were calculated by delineating the lesion area. Kaplan-Meier method and Cox proportional hazards model were conducted to analyze the independent prognosis factor. A total of 165 patients were included in this study. Respectively, the 5-year overall survival (OS) and progression-free survival (PFS) were 87.58% and 77.87%. Residual tumor size and first adjuvant treatment (AT) after surgery were both associated with PFS. In patients with small-size residual tumors, there was no significant difference in PFS between the AT treatment groups. Moreover, age, exophytic cystic components, leptomeningeal metastases, and AT were associated with OS. In patients with exophytic cystic components and those with leptomeningeal metastases, there was no significant difference in OS. Our results revealed that OPG patients could avoid or defer AT by maximized resection. Age ≤ 2 years was a disadvantageous factor for OS. Patients with exophytic cystic components were more likely to benefit from primary surgery, and CT or RT was not beneficial for these patients. Patients with leptomeningeal metastases had a poor prognosis regardless of the treatment they received. Future prospective clinical studies are needed to develop more effective treatment regimens.
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Neoplasias Encefálicas , Glioma do Nervo Óptico , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Intervalo Livre de Doença , Humanos , Neoplasia Residual , Glioma do Nervo Óptico/cirurgia , Prognóstico , Estudos RetrospectivosRESUMO
A tomographic microscopy system can achieve instantaneous three-dimensional imaging, and this type of microscopy system has been widely used in the study of biological samples; however, existing chromatographic microscopes based on off-axis Fresnel zone plates have degraded image quality due to geometric aberrations such as spherical aberration, coma aberration, and image scattering. This issue hinders the further development of chromatographic microscopy systems. In this paper, we propose a method for the design of an off-axis Fresnel zone plate with the elimination of aberrations based on double exposure point holographic surface interference. The aberration coefficient model of the optical path function was used to solve the optimal recording parameters, and the principle of the aberration elimination tomography microscopic optical path was verified. The simulation and experimental verification were carried out utilizing a Seidel coefficient, average gradient, and signal-to-noise ratio. First, the aberration coefficient model of the optical path function was used to solve the optimal recording parameters. Then, the laminar mi-coroscopy optical system was constructed for the verification of the principle. Finally, the simulation calculation results and the experimental results were verified by comparing the Seidel coefficient, average gradient, and signal-to-noise ratio of the microscopic optical system before and after the aberration elimination. The results show that for the diffractive light at the orders 0 and ±1, the spherical aberration W040 decreases by 62-70%, the coma aberration W131 decreases by 96-98%, the image dispersion W222 decreases by 71-82%, and the field curvature W220 decreases by 96-96%, the average gradient increases by 2.8%, and the signal-to-noise ratio increases by 18%.
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Holografia , Simulação por Computador , Microscopia , Razão Sinal-Ruído , Tomografia Computadorizada por Raios XRESUMO
Red-skinned pears are favored by people for their attractive appearance and abundance of anthocyanins. However, the molecular basis of anthocyanin biosynthesis in red pears remains elusive. Here, a comprehensive transcriptome analysis was conducted to explore the potential regulatory mechanism of anthocyanin biosynthesis in 'Red Zaosu' pear (Pyrus pyrifolia × Pyrus communis). Gene co-expression analysis and transcription factor mining identified 263 transcription factors, which accounted for 6.59% of the total number of transcription factors in the pear genome in two gene modules that are highly correlated with anthocyanin biosynthesis. Clustering, gene network modeling with STRING-DB, and local motif enrichment analysis (CentriMo) analysis suggested that PpPIF8 may play a role in anthocyanin biosynthesis. Furthermore, eight PIFs were identified in the pear genome, of which only PpPIF8 was rapidly induced by light. Functional studies showed that PpPIF8 localizes in the nucleus and is preferentially expressed in the tissue of higher levels of anthocyanin. The overexpression of PpPIF8 in pear peel and pear calli promotes anthocyanin biosynthesis and upregulates the expression of anthocyanin biosynthesis genes. Yeast-one hybrid and transgenic analyses indicated that PpPIF8 binds to the PpCHS promoter to induce PpCHS expression. The positive effect of PpPIF8 on anthocyanin biosynthesis is different from previously identified negative regulators of PyPIF5 and MdPIF7 in pear and apple. Taken together, our data not only provide a comprehensive view of transcription events during the coloration of pear peel, but also resolved the regulatory role of PpPIF8 in the anthocyanin biosynthesis pathway.
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Pyrus , Antocianinas/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pyrus/metabolismo , RNA-Seq , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Lead halide perovskite nanocrystals (PNCs) are emerging as promising light emitters to be actively explored for high color purity and efficient light-emitting diodes. However, the most reported lead halide perovskite nanocrystal light-emitting diodes (PNCLEDs) encountered issues of emission line width broadening and operation voltage elevating caused by the quantum confinement effect. Here, we report a new type of PNCLED using large-size CsPbBr3 PNCs overly exceeding the Bohr exciton diameter, achieving ultranarrow emission line width and rapid brightness rise around the turn-on voltage. We adopt calcium-tributylphosphine oxide hybrid ligand passivation to produce highly dispersed large-size colloidal CsPbBr3 PNCs with a weak size confinement effect and also high photoluminescence quantum yield (â¼85%). Utilizing these large-size PNCs as emitters, we manifest that the detrimental effects caused by the quantum confinement effect can be avoided in the device, thereby realizing the highest color purity in green PNCLED, with a narrow full width at half-maximum of 16.4 nm and a high corrected maximum external quantum efficiency of 17.85%. Moreover, the operation half-life time of the large-size PNCLED is 5-fold of that based on smaller-size PNCs. Our work provides a new avenue for improving the performance of PNCLEDs based on unconventional large-size effects.