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1.
Mol Carcinog ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934786

RESUMO

Cancer-associated fibroblasts (CAFs) are abundant and heterogeneous stromal cells in the tumor microenvironment, which play important roles in regulating tumor progression and therapy resistance by transferring exosomes to cancer cells. However, how CAFs modulate esophageal squamous cell carcinoma (ESCC) progression and radioresistance remains incompletely understood. The expression of fibroblast activation protein (FAP) in CAFs was evaluated by immunohistochemistry in 174 ESCC patients who underwent surgery and 78 pretreatment biopsy specimens of ESCC patients who underwent definitive chemoradiotherapy. We sorted CAFs according to FAP expression, and the conditioned medium (CM) was collected to culture ESCC cells. The expression levels of several lncRNAs that were considered to regulate ESCC progression and/or radioresistance were measured in exosomes derived from FAP+ CAFs and FAP- CAFs. Subsequently, cell counting kit-8, 5-ethynyl-2'-deoxyuridine, transwell, colony formation, and xenograft assays were performed to investigate the functional differences between FAP+ CAFs and FAP- CAFs. Finally, a series of in vitro and in vivo assays were used to evaluate the effect of AFAP1-AS1 on radiosensitivity of ESCC cells. FAP expression in stromal CAFs was positively correlated with nerve invasion, vascular invasion, depth of invasion, lymph node metastasis, lack of clinical complete response and poor survival. Culture of ESCC cells with CM/FAP+ CAFs significantly increased cancer proliferation, migration, invasion and radioresistance, compared with culture with CM/FAP- CAFs. Importantly, FAP+ CAFs exert their roles by directly transferring the functional lncRNA AFAP1-AS1 to ESCC cells via exosomes. Functional studies showed that AFAP1-AS1 promoted radioresistance by enhancing DNA damage repair in ESCC cells. Clinically, high levels of plasma AFAP1-AS1 correlated with poor responses to dCRT in ESCC patients. Our findings demonstrated that FAP+ CAFs promoted radioresistance in ESCC cells through transferring exosomal lncRNA AFAP1-AS1; and may be a potential therapeutic target for ESCC treatment.

2.
J Mol Model ; 30(6): 168, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748310

RESUMO

CONTEXT: Thermal aging significantly deteriorates the mechanical properties and service performance of epoxy resins used for the high-voltage bushing. Current studies on the thermal aging behavior of epoxy resins mainly focus on experimental observations. However, an in-depth understanding of the mechanism of thermal aging of epoxy resins requires the monitoring of structural evolution of epoxy resins during thermal aging at the molecular level. To thoroughly analyze the intrinsic factors affecting structural evolution and the effect of thermal aging on the mechanical properties of epoxy resin for high-voltage bushing, epoxy resin models with different crosslinking degrees were established and thermal aging treatments at various temperatures and time periods were carried out by molecular dynamics simulation. It was found that the tensile strength of the epoxy resin was enhanced with the increase of the crosslinking degree, which was related to the elevation of the proportion of C-N and O-H bonds in its structure. With the increase of thermal aging temperature, the tensile strength of the epoxy resin decreased, which was related to the formation of weak bonds. At the early stage of thermal aging and after a period of high-temperature thermal aging, the strength of epoxy resin significantly decreases. The thermal aging of the epoxy resin is accelerated under external loading. In addition, the crosslinking degree and curing agent also affect the thermal aging resistance of epoxy resins. The results of this study can provide guidance for predicting and improving the thermal aging resistance of epoxy resins. METHODS: Materials Studio was used to construct molecular models and complete crosslinking reactions. DGEBA and 44DDS (or 33DDS) were mixed at a ratio of 2:1, followed by crosslinking reaction. During this process, the Nose method was used to control temperature, the Berendsen method was used to control pressure, and the polymer consistent force field (PCFF) was used to control the motion and force of atoms. Isobaric-isothermal ensemble (NPT ensemble) was used to heat up epoxy resin models to various thermal aging temperatures of 400 K, 500 K, 600 K and 700 K. The models were maintained at these temperatures for different thermal aging times of 100 ps, 200 ps, 300 ps, 400 ps, 500 ps, 600 ps, 700 ps and 800 ps. Afterwards, the models were cooled down to 300 K and subjected to uniaxial tensile testing at this temperature with a strain rate of 1 × 109 s-1. The structural configurations and stress-strain data during the tensile process were recorded. The flow stress of the material was derived by counting the average stress in the 20-50% strain interval.

3.
Heliyon ; 10(8): e29647, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38655335

RESUMO

Cities are the main carriers of social and economic development, and they are also important sources of carbon emissions. Therefore, it is essential to explore the impact of urban expansion and form changes on carbon emissions. Here, we attempted to analyzes the relationship between urban expansion and carbon emissions at the county level in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 1997 to 2017. It further decomposes the driving effects of carbon emissions from multiple factors, and considers the spatial heterogeneity between different urban form changes and driving effects. The results show that: The relationship between urban expansion and carbon emissions in the GBA has gone through three stages from 1997 to 2017, with 2012 as a turning point. Optimization of economic development models and strict protection of the ecological environment can effectively control carbon emissions. After 2012, the economic development effect (GE) and population scale effect (PE) are the driving factors of carbon emissions, while the carbon emission intensity effect (CE) and urban land intensity effect (UE) are the inhibitory factors of carbon emissions. The contribution rate of UE to carbon emission reduction can reach 86 %. The impact of urban form changes on carbon emissions has spatial heterogeneity. The changes in urban form have a significant impact on the carbon emissions of counties in Dongguan and Shenzhen. The increase in fragmentation indirectly promotes carbon emissions. In 2007-2012, the increase in centrality significantly weakened the economic development effect, which is conducive to emission reduction. After 2007, the increase in compactness in counties in the eastern part of the GBA, including Zhongshan and Zhuhai, is not conducive to emission reduction.

4.
Plant Biotechnol J ; 22(8): 2312-2326, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38548388

RESUMO

Carotenoids are indispensable to plants and critical components of the human diet. The carotenoid metabolic pathway is conserved across plant species, but our understanding of the genetic basis of carotenoid variation remains limited for the seeds of most cereal crops. To address this issue, we systematically performed linkage and association mapping for eight carotenoid traits using six recombinant inbred line (RIL) populations. Single linkage mapping (SLM) and joint linkage mapping (JLM) identified 77 unique additive QTLs and 104 pairs of epistatic QTLs. Among these QTLs, we identified 22 overlapping hotspots of additive and epistatic loci, highlighting the important contributions of some QTLs to carotenoid levels through additive or epistatic mechanisms. A genome-wide association study based on all RILs detected 244 candidate genes significantly associated with carotenoid traits, 23 of which were annotated as carotenoid pathway genes. Effect comparisons suggested that a small number of loci linked to pathway genes have substantial effects on carotenoid variation in our tested populations, but many loci not associated with pathway genes also make important contributions to carotenoid variation. We identified ZmPTOX as the causal gene for a QTL hotspot (Q10/JLM10/GWAS019); this gene encodes a putative plastid terminal oxidase that produces plastoquinone-9 used by two enzymes in the carotenoid pathway. Natural variants in the promoter and second exon of ZmPTOX were found to alter carotenoid levels. This comprehensive assessment of the genetic mechanisms underlying carotenoid variation establishes a foundation for rewiring carotenoid metabolism and accumulation for efficient carotenoid biofortification.


Assuntos
Carotenoides , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Zea mays , Carotenoides/metabolismo , Zea mays/genética , Zea mays/metabolismo , Locos de Características Quantitativas/genética , Sementes/genética , Sementes/metabolismo , Ligação Genética , Epistasia Genética
5.
Sensors (Basel) ; 23(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37836985

RESUMO

Plasmonic nanostructure biosensors based on metal are a powerful tool in the biosensing field. Surface plasmon resonance (SPR) can be classified into localized surface plasmon resonance (LSPR) and propagating surface plasmon polariton (PSPP), based on the transmission mode. Initially, the physical principles of LSPR and PSPP are elaborated. In what follows, the recent development of the biosensors related to SPR principle is summarized. For clarity, they are categorized into three groups according to the sensing principle: (i) inherent resonance-based biosensors, which are sensitive to the refractive index changes of the surroundings; (ii) plasmon nanoruler biosensors in which the distances of the nanostructure can be changed by biomolecules at the nanoscale; and (iii) surface-enhanced Raman scattering biosensors in which the nanostructure serves as an amplifier for Raman scattering signals. Moreover, the advanced application of single-molecule detection is discussed in terms of metal nanoparticle and nanopore structures. The review concludes by providing perspectives on the future development of plasmonic nanostructure biosensors.

6.
Front Plant Sci ; 14: 1213675, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37636101

RESUMO

Genome-wide analyses of maize populations have clarified the genetic basis of crop domestication and improvement. However, limited information is available on how breeding improvement reshaped the genome in the process of the formation of heterotic groups. In this study, we identified a new heterotic group (X group) based on an examination of 512 Chinese maize inbred lines. The X group was clearly distinct from the other non-H&L groups, implying that X × HIL is a new heterotic pattern. We selected the core inbred lines for an analysis of yield-related traits. Almost all yield-related traits were better in the X lines than those in the parental lines, indicating that the primary genetic improvement in the X group during breeding was yield-related traits. We generated whole-genome sequences of these lines with an average coverage of 17.35× to explore genome changes further. We analyzed the identity-by-descent (IBD) segments transferred from the two parents to the X lines and identified 29 and 28 IBD conserved regions (ICRs) from the parents PH4CV and PH6WC, respectively, accounting for 28.8% and 12.8% of the genome. We also identified 103, 89, and 131 selective sweeps (SSWs) using methods that involved the π, Tajima's D, and CLR values, respectively. Notably, 96.13% of the ICRs co-localized with SSWs, indicating that SSW signals concentrated in ICRs. We identified 171 annotated genes associated with yield-related traits in maize both in ICRs and SSWs. To identify the genetic factors associated with yield improvement, we conducted QTL mapping for 240 lines from a DH population (PH4CV × PH6WC, which are the parents of X1132X) for ten key yield-related traits and identified a total of 55 QTLs. Furthermore, we detected three QTL clusters both in ICRs and SSWs. Based on the genetic evidence, we finally identified three key genes contributing to yield improvement in breeding the X group. These findings reveal key loci and genes targeted during pedigree breeding and provide new insights for future genomic breeding.

7.
Nanoscale ; 15(25): 10826-10833, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37334909

RESUMO

Gold nanoparticles (AuNPs) can be used to improve the performance of propagating surface plasmon resonance (PSPR) refractive index sensors. The resonant coupling effect between PSPR and localized surface plasmon resonance (LSPR) supported by AuNPs on sensitivity remains to be elucidated in terms of evanescent field intensity and distribution. In this study, we directly compare the sensitivity of the PSPR sensor and the resonant coupling mode between the PSPR and LSPR sensors in the wavelength scanning mode. The sensitivity of PSPR can be significantly improved in the near-infrared region excitation wavelength. 1,6-Hexanedithiol was used to achieve a AuNP modified gold film (GF-AuNP). The PSPR excited by the prism coupling mechanism can effectively stimulate LSPR supported by AuNPs in the GF-AuNP, and then resonant coupling is generated. Compared with PSPR, the resonant coupling mode shows a decrease in penetration depth by 28 times and an increase in the surface electric field intensity by 4.6 times in the numerical simulations. The decrease in the penetration depth in the GF-AuNP is made at the expense of bulk sensitivity. The biosensing sensitivity of the GF-AuNP shows up to 7-fold improvement in the carcinoembryonic antigen immunoassay and the GF-AuNP is proven to be a better biosensor. The experimental measurements are in excellent agreement with the theoretical model. This study can be also considered as a guide for the design of plasmonic sensors for detecting multiple substances at different scales, such as cells and proteins.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro , Ressonância de Plasmônio de Superfície , Modelos Teóricos
8.
Sci China Life Sci ; 66(8): 1903-1914, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37273069

RESUMO

Lactate, protein lactylation (Kla), and specifically histone lactylation have recently been shown to regulate antipathogenic immune responses in mammals. Herein, after we confirmed the presence and accumulation of lactate in maize roots under drought conditions, a lactylome profiling analysis revealed that Kla modifications were invariably present in maize roots, that there were obvious differences in the lactylomes of drought-sensitive (B73) vs. drought-tolerant (Jing2416) lines, and that growing Jing2416 under drought conditions caused significant decreases in the lactylation of multiple enzymes responsible for fatty acid degradation. Inspired by findings of histone-Kla based epigenetic regulation of immune functions in animals, we initially discovered 37 Kla sites on 16 histones in the maize genome, and again detected obvious differential histone Kla-mediated trends between two lines by ChIP-Seq. Notably, only 2.7% of genes with differential histone Kla peaks detected during drought stress were commonly present in both lines, a finding demonstrating that abiotic stress triggers distinct epigenetic activities in diverse germplasm while also strongly supporting that a histone Kla layer of regulation is associated with physiological responses to drought stress. Interestingly, exogenous application of spermidine improved the drought tolerance of B73 and substantially altered the levels of lactate, protein lactylation, and histone Kla modification. Thus, beyond extending the known domain of Kla-based biochemical and epigenetic regulation from animal immunity to plant stress physiology, our study suggests the physiological, biochemical, and genetic function of "the best-known metabolic waste", lactate.


Assuntos
Histonas , Ácido Láctico , Animais , Histonas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Secas , Epigênese Genética , Estresse Fisiológico/genética , Mamíferos
9.
Nano Lett ; 23(12): 5581-5587, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37278483

RESUMO

Metasurface-based structural color with high resolution is promising for color printing and encryption. However, achieving tunable structural colors in practical applications is challenging owing to the immutability after the fabrication of metasurfaces. Herein, we proposed the polarization-switchable dielectric metasurfaces with full colors. The colorful images can be switched on/off by controlling the polarization of incident light. For the nanorods metasurfaces, all colors turned to black in the "off" mode because of the near-zero reflection, and the uniform black was advantageous for designing encryption applications. For the nanocrosses metasurfaces, colors reversed in two different "on" modes and images hidden in the "off" mode. With the polarization-sensitive metasurfaces, a fish-bird image, an overlapped dual-channel image, and a green-red heart image were obtained, respectively. The demonstrations can be applied to dynamic displays, optical cryptography, multichannel imaging, and optical data storage.

10.
Front Plant Sci ; 14: 1168216, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251765

RESUMO

Vegetable oil is an important part of the human diet and has multiple industrial uses. The rapid increase in vegetable oil consumption has necessitated the development of viable methods for optimizing the oil content of plants. The key genes regulating the biosynthesis of maize grain oil remain mostly uncharacterized. In this study, by analyzing oil contents and performing bulked segregant RNA sequencing and mapping analyses, we determined that su1 and sh2-R mediate the shrinkage of ultra-high-oil maize grains and contribute to the increase in the grain oil content. Functional kompetitive allele-specific PCR (KASP) markers developed for su1 and sh2-R detected su1su1Sh2Sh2, Su1Su1sh2sh2, and su1su1sh2sh2 mutants among 183 sweet maize inbred lines. An RNA sequencing (RNA-seq) analysis indicated that genes differentially expressed between two conventional sweet maize lines and two ultra-high-oil maize lines were significantly associated with linoleic acid metabolism, cyanoamino acid metabolism, glutathione metabolism, alanine, aspartate, and glutamate metabolism, and nitrogen metabolism. A bulk segregant analysis and sequencing (BSA-seq) analysis identified another 88 genomic intervals related to grain oil content, 16 of which overlapped previously reported maize grain oil-related QTLs. The combined analysis of BSA-seq and RNA-seq data enabled the identification of candidate genes. The KASP markers for GRMZM2G176998 (putative WD40-like beta propeller repeat family protein), GRMZM2G021339 (homeobox-transcription factor 115), and GRMZM2G167438 (3-ketoacyl-CoA synthase) were significantly related to maize grain oil content. Another candidate gene, GRMZM2G099802 (GDSL-like lipase/acylhydrolase), catalyzes the final step of the triacylglycerol synthesis pathway and was expressed at significantly higher levels in the two ultra-high-oil maize lines than in the two conventional sweet maize lines. These novel findings will help clarify the genetic basis of the increased oil production in ultra-high-oil maize lines with grain oil contents exceeding 20%. The KASP markers developed in this study may be useful for breeding new high-oil sweet maize varieties.

11.
Front Plant Sci ; 14: 1109116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36778694

RESUMO

Southern corn rust (SCR), caused by Puccinia polysora Underw, is a destructive disease that can severely reduce grain yield in maize (Zea mays L.). Owing to P. polysora being multi-racial, it is very important to explore more resistance genes and develop more efficient selection approaches in maize breeding programs. Here, four Doubled Haploid (DH) populations with 384 accessions originated from selected parents and their 903 testcross hybrids were used to perform genome-wide association (GWAS). Three GWAS processes included the additive model in the DH panel, additive and dominant models in the hybrid panel. As a result, five loci were detected on chromosomes 1, 7, 8, 8, and 10, with P-values ranging from 4.83×10-7 to 2.46×10-41. In all association analyses, a highly significant locus on chromosome 10 was detected, which was tight chained with the known SCR resistance gene RPPC and RPPK. Genomic prediction (GP), has been proven to be effective in plant breeding. In our study, several models were performed to explore predictive ability in hybrid populations for SCR resistance, including extended GBLUP with different genetic matrices, maker based prediction models, and mixed models with QTL as fixed factors. For GBLUP models, the prediction accuracies ranged from 0.56-0.60. Compared with traditional prediction only with additive effect, prediction ability was significantly improved by adding additive-by-additive effect (P-value< 0.05). For maker based models, the accuracy of BayesA and BayesB was 0.65, 8% higher than other models (i.e., RRBLUP, BRR, BL, BayesC). Finally, by adding QTL into the mixed linear prediction model, the accuracy can be further improved to 0.67, especially for the G_A model, the prediction performance can be increased by 11.67%. The prediction accuracy of the BayesB model can be further improved significantly by adding QTL information (P-value< 0.05). This study will provide important valuable information for understanding the genetic architecture and the application of GP for SCR in maize breeding.

12.
BMC Plant Biol ; 22(1): 609, 2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36564721

RESUMO

BACKGROUND: Anthocyanins are widely applied as a marker for haploid identification after haploid induction in maize. However, the factors affecting anthocyanin biosynthesis in immature embryos and the genes regulating this process remain unclear. RESULTS: In this study, we analyzed the influence of genetic background of the male and female parents, embryo age and light exposure on anthocyanin accumulation in embryos. The results showed that light exposure was the most crucial factor enhancing the pigmentation of immature embryos. The identification accuracy of haploid embryos reached 96.4% after light exposure, but was only 11.0% following dark treatment. The total anthocyanin content was 7-fold higher in immature embryos cultured for 24 h under light conditions compared to embryos cultured in the dark. Transcriptome analysis revealed that the differentially expressed genes between immature embryos cultured for 24 h in dark and light chambers were significantly enriched in the pathways of flavonoid, flavone, flavonol and anthocyanin biosynthesis. Among the genes involved in anthocyanin biosynthesis, five up-regulated genes were identified: F3H, DFR, ANS, F3'H and the MYB transcription factor-encoding gene C1. The expression patterns of 14 selected genes were confirmed using quantitative reverse transcription-polymerase chain reaction. CONCLUSION: Light is the most important factor facilitating anthocyanin accumulation in immature embryos. After 24 h of exposure to light, the expression levels of the structural genes F3H, DFR, ANS, F3'H and transcription factor gene C1 were significantly up-regulated. This study provides new insight into the factors and key genes regulating anthocyanin biosynthesis in immature embryos, and supports improved efficiency of immature haploid embryo selection during doubled haploid breeding of maize.


Assuntos
Antocianinas , Zea mays , Antocianinas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Diploide , Melhoramento Vegetal , Perfilação da Expressão Gênica/métodos , Fatores de Transcrição/genética , Regulação da Expressão Gênica de Plantas , Transcriptoma , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Materials (Basel) ; 15(22)2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36431650

RESUMO

Lithium-ion batteries (LIBs) are at the forefront of energy storage and highly demanded in consumer electronics due to their high energy density, long battery life, and great flexibility. However, LIBs usually suffer from obvious capacity reduction, security problems, and a sharp decline in cycle life under low temperatures, especially below 0 °C, which can be mainly ascribed to the decrease in Li+ diffusion coefficient in both electrodes and electrolyte, poor transfer kinetics on the interphase, high Li+ desolvation barrier in the electrolyte, and severe Li plating and dendrite. Targeting such issues, approaches to improve the kinetics and stability of cathodes are also dissected, followed by the evaluation of the application prospects and modifications between various anodes and the strategies of electrolyte design including cosolvent, blended Li salts, high-concentration electrolyte, and additive introduction. Such designs elucidate the successful exploration of low-temperature LIBs with high energy density and long lifespan. This review prospects the future paths of research for LIBs under cold environments, aiming to provide insightful guidance for the reasonable design of LIBs under low temperature, accelerating their widespread application and commercialization.

14.
Nanotechnology ; 33(46)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35926439

RESUMO

A sensor based on plasmon-waveguide resonance (PWR) exhibits an impressive narrow linewidth and has attracted extensive attention in plasmon label-free sensing. However, the low surface electric field intensity limits the detection ability of biomolecules, where the refractive index changes are restricted at the sensor surface. In this study, we study the coupling of PWR and multiple plasma modes in a hyperbolic metamaterial (HMM), combining narrow linewidth and electric field enhancement advantages. The PWR-HMM sensor includes a gold film, lossless dielectric layer, and metal/dielectric multilayer HMM array composed of 2-layer Au/Al2O3stacks. The evanescent field of PWR is used to excite multiple plasma modes in the HMM. The figure of merit of the proposed structure reaches 5417/RIU owing to the existence of lossless dielectric layer, which is 11.7 times than the conventional gold film structure. The maximum bulk sensitivity of the PWR-HMM sensor was 43 000 nm/RIU. In comparison with PWR, the surface electric field intensity and the surface sensitivity of PWR-HMM increase by four and two times, respectively. Furthermore, comparing the sensing performance of the PWR-HMM sensor and PWR-nanoparticle (NP) sensor (coupling PWR and localized surface plasmon resonance), it was found that PWR-HMM has 20% higher surface sensitivity than the PWR-NP. A sensing mechanism coupling PWR and multiple plasma modes in the HMMs opens a gate to significantly improve the PWR sensors performance, which is expected to be used to resolve urgent issues in biological, medical and clinical applications.

15.
Theor Appl Genet ; 135(9): 3039-3055, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35788748

RESUMO

KEY MESSAGE: The novel ZmR1CQ01 allele for maize anthocyanin synthesis was identified, and the biological function and regulatory molecular mechanisms of three ZmR1 alleles were unveiled. Anthocyanins in maize are valuable to human health. The R1 gene family is one of the important regulatory genes for the tissue-specific distribution of anthocyanins. R1 gene allelic variations are abundant and its biological function and regulatory molecular mechanisms are not fully understood. By exploiting genetic mapping and transgenic verification, we found that anthocyanin pigmentation in maize leaf midrib was controlled by ZmR1 on chromosome 10. Allelism test of maize zmr1 EMS mutants confirmed that anthocyanin pigmentation in leaf sheath was also controlled by ZmR1. ZmR1CQ01 was a novel ZmR1 allelic variation obtained from purple maize. Its overexpression caused the whole maize plant to turn purple. ZmR1B73 allele confers anthocyanin accumulation in near ground leaf sheath rather than in leaf midribs. The mRNA expression level of ZmR1B73 was low in leaf midribs, resulting in no anthocyanin accumulation. ZmR1B73 overexpression promoted anthocyanin accumulation in leaf midribs. Loss of exon 5 resulted in ZmR1ZN3 allele function destruction and no anthocyanin accumulation in leaf midrib and leaf sheath. DNA affinity purification sequencing revealed 1010 genes targeted by ZmR1CQ01, including the bz2 in anthocyanin synthesis pathway. RNA-seq analysis showed 55 genes targeted by ZmR1CQ01 changed the expression level significantly, and the expression of genes encoding key enzymes in flavonoid and phenylpropanoid biosynthesis pathways were significantly up-regulated. ZmR1 functional molecular marker was developed. These results revealed the effects of transcriptional regulation and sequence variation on ZmR1 function and identified the genes targeted by ZmR1CQ01 at the genome-wide level.


Assuntos
Antocianinas , Zea mays , Alelos , DNA , Regulação da Expressão Gênica de Plantas , Pigmentação/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , RNA Mensageiro , Zea mays/genética , Zea mays/metabolismo
16.
Front Plant Sci ; 13: 951318, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903220

RESUMO

Southern corn rust (SCR) caused by Puccinia polysora Underw. poses a major threat to maize production worldwide. The utilization of host SCR-resistance genes and the cultivation of resistant cultivars are the most effective, economical strategies for controlling SCR. Here, we identified and cloned a new SCR resistance gene, RppM, from the elite maize inbred line Jing2416K. RppM was found to encode a typical CC-NBS-LRR protein localized in both the nucleus and cytoplasm. This gene was constitutively expressed at all developmental stages and in all tissues examined, with the strongest expression detected in leaves at the mature stage. A transcriptome analysis provided further evidence that multiple defense systems were initiated in Jing2416K, including pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity, reinforcement of cell walls, accumulation of antimicrobial compounds, and activation of phytohormone signaling pathways. Finally, we developed functional Kompetitive allele-specific PCR markers for RppM using two conserved SNP sites and successfully applied these functional markers for the detection of RppM and the cultivation of resistant maize cultivars, demonstrating their great potential utility in maize breeding.

17.
Front Aging Neurosci ; 14: 911513, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35686023

RESUMO

Hemiplegia is a common motor dysfunction caused by a stroke. However, the dynamic network mechanism of brain processing information in post-stroke hemiplegic patients has not been revealed when performing motor imagery (MI) tasks. We acquire electroencephalography (EEG) data from healthy subjects and post-stroke hemiplegic patients and use the Fugl-Meyer assessment (FMA) to assess the degree of motor function damage in stroke patients. Time-varying MI networks are constructed using the adaptive directed transfer function (ADTF) method to explore the dynamic network mechanism of MI in post-stroke hemiplegic patients. Finally, correlation analysis has been conducted to study potential relationships between global efficiency and FMA scores. The performance of our proposed method has shown that the brain network pattern of stroke patients does not significantly change from laterality to bilateral symmetry when performing MI recognition. The main change is that the contralateral motor areas of the brain damage and the effective connection between the frontal lobe and the non-motor areas are enhanced, to compensate for motor dysfunction in stroke patients. We also find that there is a correlation between FMA scores and global efficiency. These findings help us better understand the dynamic brain network of patients with post-stroke when processing MI information. The network properties may provide a reliable biomarker for the objective evaluation of the functional rehabilitation diagnosis of stroke patients.

18.
Front Endocrinol (Lausanne) ; 13: 872153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527993

RESUMO

BRAFV600E is the most common mutated gene in thyroid cancer and is most closely related to papillary thyroid carcinoma(PTC). We investigated the value of elasticity and grayscale ultrasonography for predicting BRAFV600E mutations in PTC. Methods: 138 patients with PTC who underwent preoperative ultrasound between January 2014 and 2021 were retrospectively examined. Patients were divided into BRAFV600E mutation-free group (n=75) and BRAFV600E mutation group (n=63). Patients were randomly divided into training (n=96) and test (n=42) groups. A total of 479 radiomic features were extracted from the grayscale and elasticity ultra-sonograms. Regression analysis was done to select the features that provided the most information. Then, 10-fold cross-validation was used to compare the performance of different classification algorithms. Logistic regression was used to predict BRAFV600E mutations. Results: Eight radiomics features were extracted from the grayscale ultrasonogram, and five radiomics features were extracted from the elasticity ultrasonogram. Three models were developed using these radiomic features. The models were derived from elasticity ultrasound, grayscale ultrasound, and a combination of grayscale and elasticity ultrasound, with areas under the curve (AUC) 0.952 [95% confidence interval (CI), 0.914-0.990], AUC 0.792 [95% CI, 0.703-0.882], and AUC 0.985 [95% CI, 0.965-1.000] in the training dataset, AUC 0.931 [95% CI, 0.841-1.000], AUC 0. 725 [95% CI, 0.569-0.880], and AUC 0.938 [95% CI, 0.851-1.000] in the test dataset, respectively. Conclusion: The radiomic model based on grayscale and elasticity ultrasound had a good predictive value for BRAFV600E gene mutations in patients with PTC.


Assuntos
Proteínas Proto-Oncogênicas B-raf , Neoplasias da Glândula Tireoide , Elasticidade , Humanos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos , Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia
19.
J Agric Food Chem ; 70(21): 6407-6417, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35588298

RESUMO

Dietary ω-3 PUFAs are highly prone to oxidation, and this may potentially limit their application in the health-promoting field. Here, we sought to investigate whether and how oxidized PUFAs modulate the susceptibility of mice to Salmonella typhimurium (S. Tm) infection. Algae oil (AO) and oxidized algae oil (ox-AO) were administered to the C57BL/6 mice prior to S. Tm infection. Compared to the S. Tm group, ox-AO increased bacterial burden in systemic and intestinal tissues, downregulated host anti-infection responses, and developed worse colitis. In macrophages, ox-AO decreased both phagocytosis of S. Tm and clearance of intracellular bacteria and dampened the activation of mitogen-activated protein kinase (MAPK), NF-κB, and autophagy pathways. Furthermore, ox-AO diminished LPS-induced inflammatory cytokine production and S. Tm induced NLRC4 inflammasome activation. This study reveals that oxidized PUFAs may contribute to the development of enteric infections and regular monitoring of the oxidation status in commercial PUFA supplements to prevent their potential adverse impact on human health.


Assuntos
Infecções por Salmonella , Animais , Imunidade Inata , Inflamassomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/microbiologia , Salmonella typhimurium
20.
Cancer Manag Res ; 14: 1285-1292, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35378782

RESUMO

Purpose: To explore the separate diagnostic value of preoperative ultrasound (US), magnetic resonance imaging (MRI), and the combination of US and MRI in extrathyroidal extension (ETE) of papillary thyroid carcinoma (PTC). Materials and Methods: This retrospective study was approved by the Affiliated People's Hospital of Jiangsu University review board. A total of 158 PTC patients with ETE received preoperative US and MRI examination and underwent surgery between May 2014 and December 2018 in Affiliated People's Hospital of Jiangsu University. For each case, the US and MRI features of ETE were retrospectively and independently investigated by two radiologists. The clinical assessment for each case was implemented, respectively, using US imaging only, MRI only, and a combination of both modalities at three different time points with one-month intervals. Results: The diagnostic accuracies of US, MRI, and the combined set for T3 (minimal ETE) were 91.7% (88/96), 74.0% (71/96), and 97.9% (94/96), respectively, indicating a significantly different performance (P < 0.001). The diagnostic accuracies for T4 (extensive ETE) were 62.9% (39/62), 87.1% (54/62), and 93.5% (58/62), respectively. The difference between the three methods for T4 was statistically significant (P = 0.000). The diagnostic accuracies for overall ETE were 80.4% (127/158), 79.1% (125/158), and 96.2% (152/158), respectively. The difference between the three methods for ETE was statistically significant (P = 0.001). Conclusion: This study suggests that ETE can be predicted most accurately by the combination of preoperative US and MRI.

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