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1.
Environ Res ; 258: 119453, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38909951

RESUMO

Thermophilic anaerobic digestion (AD) of animal manure offers various environmental benefits but the process requires a microbial community acclimatized to high ammonia. In current study, a lab-scale continuous stirred tank reactor (CSTR) fed with chicken manure was operated under thermophilic condition for 450 days in total. Results showed that the volumetric methane production decreased from 445 to 328 and sharply declined to 153 mL L-1·d-1 with feeding total solid (TS) step increased from 5% to 7.5% and 10%, respectively. While, after a long-term stop feeding for 80 days, highly disturbed reactor was able to recover methane generation to 739 mL L-1·d-1 at feeding TS of 10%. Isotope analysis indicted acetate converted to methane through the syntrophic acetate oxidation and hydrogenotrophic methanogenesis (SAO-HM) pathway increased from 33% to 63% as the concentration of ammonium increased from 2493 to 6258 mg L-1. Significant different in the genome expression of the SAO bacterial from 0.09% to 1.23%, combining with main hydrogenotrophic partners (Methanoculleus spp. and Methanothermobacter spp.) contented of 2.1% and 99.9% during inhibitory and recovery stages, respectively. The highly expressed KEGG pathway in level 3 (enzyme genes) for the Recovery sludge combining with the extraordinary high abundance of genera Halocella sp. suggested that Halocella sp. might be a highly efficient hydrolytic and acidogenic microorganism and enhance the process of SAO during carbon metabolic flow to methane. This report will be a basis for further study of AD studies on high nitrogen content of poultry manure.

2.
Neurosurg Rev ; 47(1): 108, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456994

RESUMO

This study aimed to assess the effectiveness and safety of robot-assisted versus fluoroscopy-assisted pedicle screw implantation in scoliosis surgery. The study was registered in the PROSPERO (CRD42023471837). Two independent researchers searched PubMed, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. The outcomes included operation time, pedicle screw implantation time, blood loss, number of fluoroscopic, accuracy of pedicle screw position, hospital stays, postoperative hospital stays, Visual Analog Scale (VAS), Japanese Orthopaedic Association (JOA) score, Scoliosis Research Society-22(SRS-22), cobb angle, cobb angle correction rate, sagittal vertical axis (SVA), and complications. Eight papers involving 473 patients met all the criteria. There was no significant difference between the two groups regarding the reduction in operation time. The effect of reducing the pedicle screw implantation time in the RA group was significant (WMD = -1.28; 95% CI: -1.76 to -0.80; P < 0.00001). The effect of reducing the blood loss in the RA group was significant (WMD=-105.57; 95% CI: -206.84 to -4.31; P = 0.04). The effect of reducing the number of fluoroscopic in the RA group was significant (WMD=-5.93; 95% CI: -8.24 to -3.62; P < ). The pedicle screw position of Grade A was significantly more in the RA group according to both the Gertzbein-Robbins scale and the Rampersaud scale. Compared with the FA group, the difference in the hospital stays in the RA group was not statistically significant, but the effect of reducing the postoperative hospital stays in the RA group was significant (WMD = -2.88; 95% CI: -4.13 to -1.63; P < 0.00001). The difference in the VAS, JOA, SRS-22, Cobb angle and Cobb angle correction rate, SVA, and complications between the two groups was not statistically significant. The robot-assisted technique achieved statistically significant results in terms of pedicle screw placement time, blood loss, number of fluoroscopies, accuracy of pedicle screw position, and postoperative hospital stay.


Assuntos
Parafusos Pediculares , Procedimentos Cirúrgicos Robóticos , Robótica , Escoliose , Fusão Vertebral , Humanos , Fluoroscopia/métodos , Vértebras Lombares/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos , Escoliose/cirurgia , Fusão Vertebral/métodos
3.
BMC Microbiol ; 23(1): 123, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37158877

RESUMO

COVID-19 has emerged as a global pandemic, challenging the world's economic and health systems. Human oral microbiota comprises the second largest microbial community after the gut microbiota and is closely related to respiratory tract infections; however, oral microbiomes of patients who have recovered from COVID-19 have not yet been thoroughly studied. Herein, we compared the oral bacterial and fungal microbiota after clearance of SARS-CoV-2 in 23 COVID-19 recovered patients to those of 29 healthy individuals. Our results showed that both bacterial and fungal diversity were nearly normalized in recovered patients. The relative abundance of some specific bacteria and fungi, primarily opportunistic pathogens, decreased in recovered patients (RPs), while the abundance of butyrate-producing organisms increased in these patients. Moreover, these differences were still present for some organisms at 12 months after recovery, indicating the need for long-term monitoring of COVID-19 patients after virus clearance.


Assuntos
COVID-19 , Microbiota , Micobioma , Humanos , SARS-CoV-2 , Bactérias/genética
4.
Plant Physiol ; 190(4): 2797-2811, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36149297

RESUMO

Transcription activation is tightly associated with the openness of chromatin and allows direct contact between transcriptional regulators and their targeted DNA for gene expression. However, there are limited studies on the annotation of open chromatin regions (OCRs) in rice (Oryza sativa), especially those in reproductive organs. Here, we characterized OCRs in rice pistils and anthers with an assay for transposase-accessible chromatin using sequencing. Despite a large overlap, we found more OCRs in pistils than in anthers. These OCRs were enriched in gene transcription start sites (TSSs) and showed tight associations with gene expression. Transcription factor (TF) binding motifs were enriched at these OCRs as validated by TF chromatin immunoprecipitation followed by sequencing. Pistil-specific OCRs provided potential regulatory networks by binding directly to the targets, indicating that pistil-specific OCRs may be indicators of cis-regulatory elements in regulating pistil development, which are absent in anthers. We also found that open chromatin of pistils and anthers responded differently to low temperature (LT). These data offer a comprehensive overview of OCRs regulating reproductive organ development and LT responses in rice.


Assuntos
Cromatina , Oryza , Cromatina/genética , Oryza/genética , Oryza/metabolismo , Imunoprecipitação da Cromatina , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Flores/genética , Flores/metabolismo
5.
Physiol Plant ; 175(4): e13962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37343119

RESUMO

The GRAS transcription factors play an indispensable role in plant growth and responses to environmental stresses. The GRAS gene family has extensively been explored in various plant species; however, the comprehensive investigation of GRAS genes in white lupin remains insufficient. In this study, bioinformatics analysis of white lupin genome revealed 51 LaGRAS genes distributed into 10 distinct phylogenetic clades. Gene structure analyses revealed that LaGRAS proteins were considerably conserved among the same subfamilies. Notably, 25 segmental duplications and a single tandem duplication showed that segmental duplication was the major driving force for the expansion of GRAS genes in white lupin. Moreover, LaGRAS genes exhibited preferential expression in young cluster root and mature cluster roots and may play key roles in nutrient acquisition, particularly phosphorus (P). To validate this, RT-qPCR analysis of white lupin plants grown under +P (normal P) and -P (P deficiency) conditions elucidated significant differences in the transcript level of GRAS genes. Among them, LaGRAS38 and LaGRAS39 were identified as potential candidates with induced expression in MCR under -P. Additionally, white lupin transgenic hairy root overexpressing OE-LaGRAS38 and OE-LaGRAS39 showed increased root growth, and P concentration in root and leaf compared to those with empty vector control, suggesting their role in P acquisition. We believe this comprehensive analysis of GRAS members in white lupin is a first step in exploring their role in the regulation of root growth, tissue development, and ultimately improving P use efficiency in legume crops under natural environments.


Assuntos
Lupinus , Fósforo , Fósforo/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/genética
6.
BMC Geriatr ; 23(1): 590, 2023 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-37742001

RESUMO

BACKGROUND: Sleep and circadian rhythm disorders are well recognised in both AD (Alzheimer's Disease) dementia and MCI-AD (Mild Cognitive Impairment due to Alzheimer's Disease). Such abnormalities include insomnia, excessive daytime sleepiness, decreased sleep efficiency, increased sleep fragmentation and sundowning. Enhancing understanding of sleep abnormalities may unveil targets for intervention in sleep, a promising approach given hypotheses that sleep disorders may exacerbate AD pathological progression and represent a contributory factor toward impaired cognitive performance and worse quality of life. This may also permit early diagnosis of AD pathology, widely acknowledged as a pre-requisite for future disease-modifying therapies. This study aims to bridge the divide between in-laboratory polysomnographic studies which allow for rich characterisation of sleep but in an unnatural setting, and naturalistic studies typically approximating sleep through use of non-EEG wearable devices. It is also designed to record sleep patterns over a 2 month duration sufficient to capture both infradian rhythm and compensatory responses following suboptimal sleep. Finally, it harnesses an extensively phenotyped population including with AD blood biomarkers. Its principal aims are to improve characterisation of sleep and biological rhythms in individuals with AD, particularly focusing on micro-architectural measures of sleep, compensatory responses to suboptimal sleep and the relationship between sleep parameters, biological rhythms and cognitive performance. METHODS/DESIGN: This observational cohort study has two arms (AD-MCI / mild AD dementia and aged-matched healthy adults). Each participant undergoes a baseline visit for collection of demographic, physiological and neuropsychological information utilising validated questionnaires. The main study period involves 7 nights of home-based multi-channel EEG sleep recording nested within an 8-week study period involving continuous wrist-worn actigraphy, sleep diaries and regular brief cognitive tests. Measurement of sleep parameters will be at home thereby obtaining a real-world, naturalistic dataset. Cognitive testing will be repeated at 6 months to stratify participants by longitudinal disease progression. DISCUSSION: This study will generate new insights particularly in micro-architectural measures of sleep, circadian patterns and compensatory sleep responses in a population with and without AD neurodegenerative change. It aims to enhance standards of remotely based sleep research through use of a well-phenotyped population and advanced sleep measurement technology.


Assuntos
Doença de Alzheimer , Demência , Humanos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/terapia , Qualidade de Vida , Sono , Estudos de Coortes , Estudos Observacionais como Assunto
7.
Luminescence ; 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38148620

RESUMO

Photodynamic therapy (PDT) represents an emerging noninvasive treatment technique for cancers and various nonmalignant diseases, including infections. During the process of PDT, the physical and chemical properties of photosensitizers (PSs) critically determine the effectiveness of PDT. Traditional PSs have made great progress in clinical applications. One of the challenges is that traditional PSs suffer from aggregation-caused quenching (ACQ) due to their discotic structures. Recently, aggregation-induced emission PSs (AIE-PSs) with a twisted propeller-shaped conformation have been widely concerned because of high reactive oxygen species (ROS) generation efficiency, strong fluorescence efficiency, and resistance to photobleaching. However, AIE-PSs also have some disadvantages, such as short absorption wavelengths and insufficient molar absorption coefficient. When the advantages and disadvantages of AIE-PSs and ACQ-PSs are complementary, combining ACQ-PSs and AIE-PSs is a "win-to-win" strategy. As far as we know, the conversion of traditional representative ACQ-PSs to AIE-PSs for phototheranostics has not been reviewed. In the review, we summarize the recent progress on the ACQ-to-AIE transformation of PSs and the strategies to achieve desirable theranostic applications. The review would be helpful to design more efficient ACQ-AIE-PSs in the future and to accelerate the development and clinical application of PDT.

8.
BMC Plant Biol ; 22(1): 70, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35176996

RESUMO

BACKGROUND: Seed germination is a crucial process, which determines the initiation of seed plant life cycle. The early events during this important life cycle transition that called early seed germination is defined as initially water uptake plus radicle growing out of the covering seed layers. However, a specific genome-wide analysis of early seed germination in rice is still obscure. RESULTS: In this study, the physiological characteristics of rice seed during seed germination are determined to define key points of early seed germination. Transcriptome analyses of early phase of seed germination provided deeper insight into the genetic regulation landscape. Many genes involved in starch-to-sucrose transition were differentially expressed, especially alpha-amylase 1b and beta-amylase 2, which were predominantly expressed. Differential exon usage (DEU) genes were identified, which were significantly enriched in the pathway of starch and sucrose metabolism, indicating that DEU events were critical for starch-to-sucrose transition at early seed germination. Transcription factors (TFs) were also dramatic expressed, including the abscisic acid (ABA) responsive gene, OsABI5, and gibberellic acid (GA) responsive genes, GAI. Moreover, GAI transactivated GA responsive gene, GAMYB in vivo, indicating a potential pathway involved in early seed germination process. In addition, CBL-interacting protein kinase (CIPK) genes, such as CIPK13, CIPK14 and CIPK17 were potentially interacted with other proteins, indicating its pivotal role at early seed germination. CONCLUSION: Taken together, gene regulation of early seed germination in rice was complex and protein-to-gene or protein-to-protein interactions were indispensable.


Assuntos
Germinação/genética , Oryza/genética , Sementes/genética , Ácido Abscísico/metabolismo , Éxons , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Oryza/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Mapas de Interação de Proteínas/genética , Sementes/crescimento & desenvolvimento , Amido/genética , Amido/metabolismo , Sacarose/metabolismo , Fatores de Transcrição/genética
9.
Plant J ; 101(3): 604-618, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31621135

RESUMO

Carbon reserves in rice straw before flowering contribute greatly to grain filling. Moderate soil drying imposed at the post-anthesis stage significantly promotes carbon reserve remobilization in straws of rice, but the regulation of this process at the proteomic and transcriptomic level remains poorly understood. In this study, we applied moderate soil drying (MD) to rice at the post-anthesis stage, which was followed by dynamic proteomic and transcriptomic studies using SWATH-MS and RNA-seq analysis. MD treatment upregulated the proteins alpha-glucosidase, beta-glucosidase and starch phosphorylase, which are responsible for starch degradation. Furthermore, MD treatment enhanced the expression of proteins involved in the sucrose synthesis pathway, including SPS8 and SPP1. In addition, various monosaccharide transporters (MSTs) and sucrose transporter 2 (SUT2), which are pivotal in carbon reserve remobilization, were also upregulated in straw by MD treatment. Differentially expressed transcription factors, including GRAS, TCP, trihelix, TALE, C3H, and NF-YC, were predicted to interact with other proteins to mediate carbon reserve remobilization in response to MD treatment. Further correlation analysis revealed that the abundances of most of the differentially expressed proteins were not correlated with the corresponding transcript levels, indicating that the carbon reserve remobilization process was probably regulated by posttranscriptional modification. Our results provide insights into the molecular mechanisms underlying the regulation of carbon reserve remobilization from straw to grain in rice under MD conditions.


Assuntos
Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Membrana Transportadoras/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Proteômica , Solo/química , Transporte Biológico , Dessecação , Grão Comestível , Proteínas de Membrana Transportadoras/genética , Proteínas de Transporte de Monossacarídeos/genética , Proteínas de Transporte de Monossacarídeos/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/fisiologia , Proteínas de Plantas/genética , Amido/metabolismo , Sacarose/metabolismo
10.
New Phytol ; 230(5): 1925-1939, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33629374

RESUMO

Seed germination is essential for direct seeding in rice. It has been demonstrated that trehalose-6-phosphate phosphatase 1 (OsTPP1) plays roles in improving yield and stress tolerance in rice. In this study, the roles of OsTPP1 on seed germination in rice were investigated. The tpp1 mutant germinated slower than the wild-type (WT), which can be restored by exogenous trehalose. tpp1 seeds showed higher ABA content compared with WT seeds. The tpp1 mutant was hypersensitive to ABA and ABA catabolism inhibitor (Dinicozanole). Furthermore, two ABA catabolism genes were downregulated in the tpp1 mutant which were responsible for increased ABA concentrations, and exogenous trehalose increased transcripts of ABA catabolism genes, suggesting that OsTPP1 and ABA catabolism genes acted in the same signaling pathway. Further analysis showed that a transcription factor of OsGAMYB was an activator of OsTPP1, and expression of OsGAMYB was decreased by both the exogenous and endogenous ABA, subsequently reducing the expression of OsTPP1, which suggested a new signaling pathway required for seed germination in rice. In addition, ABA-responsive genes, especially OsABI5, were invoved in OsTPP1-mediated seed germination. Overall, our study provided new pathways in seed germination that OsTPP1 controlled seed germination through crosstalk with the ABA catabolism pathway.


Assuntos
Ácido Abscísico , Oryza , Ácido Abscísico/farmacologia , Regulação da Expressão Gênica de Plantas , Germinação , Oryza/genética , Sementes
11.
Plant Physiol ; 183(4): 1809-1824, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513834

RESUMO

In rice (Oryza sativa), a specific temporary source organ, the stem, is important for grain filling, and moderate soil drying (MD) enhanced carbon reserve flow from stems to increase grain yield. The dynamics and biological relevance of DNA methylation in carbon reserve remobilization during grain filling are unknown. Here, we generated whole-genome single-base resolution maps of the DNA methylome in the stem. During grain filling under MD, we observed an increase in DNA methylation of total cytosines, with more hypomethylated than hypermethylated regions. Genes responsible for DNA methylation and demethylation were up-regulated, suggesting that DNA methylation changes in the stem were regulated by antagonism between DNA methylation and demethylation activity. In addition, methylation in the CG and CHG contexts was negatively associated with gene expression, while that in the CHH context was positively associated with gene expression. A hypermethylated/up-regulated transcription factor of MYBS2 inhibited MYB30 expression and possibly enhanced ß-Amylase5 expression, promoting subsequent starch degradation in rice stems under MD treatment. In addition, a hypermethylated/down-regulated transcription factor of ERF24 was predicted to interact with, and thereby decrease the expression of, abscisic acid 8'-hydroxylase1, thus increasing abscisic acid concentration under MD treatment. Our findings provide insight into the DNA methylation dynamics in carbon reserve remobilization of rice stems, demonstrate that MD increased this remobilization, and suggest a link between DNA methylation and gene expression in rice stems during grain filling.


Assuntos
Epigenoma/genética , Oryza/genética , Metilação de DNA/genética , Metilação de DNA/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
J Exp Bot ; 72(4): 1384-1398, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33130853

RESUMO

Moderate soil drying (MD) imposed at the post-anthesis stage significantly improves carbon reserve remobilization in rice stems, increasing grain yield. However, the methylome and transcriptome profiles of carbon reserve remobilization under MD are obscure in indica and japonica rice stems. Here, we generated whole-genome single-base resolution maps of the DNA methylome in indica and japonica rice stems. DNA methylation levels were higher in indica than in japonica and positively correlated with genome size. MD treatment had a weak impact on the changes in methylation levels in indica. Moreover, the number of differentially methylated regions was much lower in indica, indicating the existence of cultivar-specific methylation patterns in response to MD during grain filling. The gene encoding ß-glucosidase 1, involved in the starch degradation process, was hypomethylated and up-regulated in indica, resulting in improved starch to sucrose conversion under MD treatment. Additionally, increased expression of MYBS1 transactivated the expression of AMYC2/OsAMY2A in both indica and japonica, leading to enhanced starch degradation under MD. In contrast, down-regulated expression of MYB30 resulted in increased expression of BMY5 in both cultivars. Our findings decode the dynamics of DNA methylation in indica and japonica rice stems and propose candidate genes for improving carbon reserve remobilization.


Assuntos
Oryza , Carbono , Epigenoma , Perfilação da Expressão Gênica , Oryza/genética , Solo
13.
Chem Soc Rev ; 49(4): 1144-1172, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31971181

RESUMO

The emergence of aggregation-induced emission luminogens (AIEgens) has significantly stimulated the development of luminescent supramolecular materials because their strong emissions in the aggregated state have resolved the notorious obstacle of the aggregation-caused quenching (ACQ) effect, thereby enabling AIEgen-based supramolecular materials to have a promising prospect in the fields of luminescent materials, sensors, bioimaging, drug delivery, and theranostics. Moreover, in contrast to conventional fluorescent molecules, the configuration of AIEgens is highly twisted in space. Investigating AIEgens and the corresponding supramolecular materials provides fundamental insights into the self-assembly of nonplanar molecules, drastically expands the building blocks of supramolecular materials, and pushes forward the frontiers of supramolecular chemistry. In this review, we will summarize the basic concepts, seminal studies, recent trends, and perspectives in the construction and applications of AIEgen-based supramolecular materials with the hope to inspire more interest and additional ideas from researchers and further advance the development of supramolecular chemistry.


Assuntos
Substâncias Luminescentes/química , Imagem Óptica , Nanomedicina Teranóstica , DNA/química , Portadores de Fármacos/química , Humanos , Compostos Macrocíclicos/química , Microscopia Confocal , Neoplasias/diagnóstico por imagem , Peptídeos/química
14.
Macromol Rapid Commun ; 41(3): e1900579, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31867797

RESUMO

A method for generating hierarchical scaffolds with graded changes in porosity and/or fiber alignment through solution-masked, vapor-induced welding of electrospun poly(lactic-co-glycolic acid) (PLGA) nanofibers is reported. The success of this method relies on the fact that the PLGA nanofibers are swollen and welded more slowly by ethanol when immersed in its aqueous solution relative to direct exposure to its vapor. For a mat composed of random nanofibers, the treatment generates a gradation in porosity (both surface and bulk), with the over-welded region evolving from a highly porous mat into a dense film. If uniaxially aligned nanofibers are involved, however, graded changes are observed in both surface porosity and fiber alignment. When bone marrow stem cells are cultured on such a scaffold, they exhibit highly organized and random morphologies on the regions of uniaxially aligned nanofibers and dense film, respectively, with gradual changes in between. Such a scaffold shows promise in mimicking the connective tissue, such as the tendon-to-bone insertion, that relies on a graded transition in cell morphology from uniaxially aligned to random.


Assuntos
Glicolatos/química , Nanofibras/química , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Tecido Conjuntivo , Células-Tronco Hematopoéticas/citologia , Cinética , Nanofibras/ultraestrutura , Porosidade
15.
J Integr Plant Biol ; 62(2): 201-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30920762

RESUMO

Chromatins are not randomly packaged in the nucleus and their organization plays important roles in transcription regulation, which is best studied in the mammalian models. Using in situ Hi-C, we have compared the 3D chromatin architectures of rice mesophyll and endosperm, foxtail millet bundle sheath and mesophyll, and maize bundle sheath, mesophyll and endosperm tissues. We found that their global A/B compartment partitions are stable across tissues, while local A/B compartment has tissue-specific dynamic associated with differential gene expression. Plant domains are largely stable across tissues, while new domain border formations are often associated with transcriptional activation in the region. Genes inside plant domains are not conserved across species, and lack significant co-expression behavior unlike those in mammalian TADs. Although we only observed chromatin loops between gene islands in the large genomes, the maize loop gene pairs' syntenic orthologs have shorter physical distances in small genome monocots, suggesting that loops instead of domains might have conserved biological function. Our study showed that plants' chromatin features might not have conserved biological functions as the mammalian ones.


Assuntos
Oryza/genética , Oryza/metabolismo , Setaria (Planta)/genética , Setaria (Planta)/metabolismo , Zea mays/genética , Zea mays/metabolismo , Cromatina/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genoma de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
16.
Angew Chem Int Ed Engl ; 59(46): 20371-20375, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32767633

RESUMO

Using reverse thinking of the aggregation-induced emission (AIE) principle, we demonstrate an ingenious and universal protocol for amplifying molecular motions to boost photothermal efficiency of fibers. Core-shell nanofibers having the olive oil solution of AIE-active molecules as the core surrounded by PVDF-HFP shell were constructed by coaxial electrospinning. The molecularly dissolved state of AIE-active molecules allows them to freely rotate and/or vibrate in nanofibers upon photoexcitation and thus significantly elevates the proportion of non-radiative energy dissipation, affording impressive heat-generating efficiency. Photothermal evaluation shows that the core-shell nanofibers with excellent durability can reach up to 22.36 % of photothermal conversion efficiency, which is 26-fold as the non-core-shell counterpart. Such a core-shell fiber can be used for photothermal textiles and solar steam generation induced by natural sunlight with green and carbon-zero emission.

17.
J Exp Bot ; 70(5): 1597-1611, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30690492

RESUMO

Moderate soil drying imposed at the post-anthesis stage significantly increases starch accumulation in inferior grains of rice, but how this process is regulated at the level of gene expression remains unclear. In this study, we applied moderate drying (MD) treatments to the soil at the post-anthesis stage and followed the dynamics of the conversion process of soluble sugars to starch in inferior grains using RNA-seq analysis. An elevated level of ABA induced by MD was consistently associated with down-regulation of ABA8ox2, suggesting that lower expression of this gene may be responsible for the higher ABA content, potentially resulting in better filling in inferior grains. In addition, MD treatments up-regulated genes encoding five key enzymes involved sucrose-to-starch conversion and increased the activities of enzymes responsible for soluble-sugar reduction and starch accumulation in inferior grains. Differentially expressed transcription factors, including NAC, GATA, WRKY, and M-type MADS, were predicted to interact with other proteins in mediating filling of inferior grains as a response to MD. Transient expression analysis showed that NAC activated WAXY expression by binding to its promoter, indicating that NAC played a key role in starch synthesis of inferior grains under MD treatment. Our results provide new insights into the molecular mechanisms that regulate grain filling in inferior grains of rice under moderate soil drying.


Assuntos
Dessecação , Grão Comestível/crescimento & desenvolvimento , Oryza/fisiologia , Solo/química , Transcriptoma , Grão Comestível/genética
18.
Angew Chem Int Ed Engl ; 58(46): 16416-16421, 2019 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-31373102

RESUMO

We report a simple method for the photothermal welding of nonwoven mats of electrospun nanofibers by introducing a near-infrared (NIR) dye such as indocyanine green. By leveraging the strong photothermal effect of the dye, the nanofibers can be readily welded at their cross points or even over-welded (i.e., melted and/or fused together) to transform the porous mat into a solid film upon exposure to a NIR laser. While welding at the cross points greatly improves the mechanical strength of a nonwoven mat of nanofibers, melting and fusion of the nanofibers can be employed to fabricate a novel class of photothermal papers for laser writing or printing without chemicals or toner particles. By using a photomask, we can integrate photothermal welding with the gas foaming technique to pattern and then expand nonwoven mats into 3D scaffolds with well-defined structures. This method can be applied to different combinations of polymers and dyes, if they can be co-dissolved in a suitable solvent for electrospinning.


Assuntos
Lasers , Nanofibras/química , Polímeros/química , Animais , Verde de Indocianina/química , Raios Infravermelhos , Camundongos , Células NIH 3T3 , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais/química , Soldagem
19.
Plant J ; 90(2): 304-318, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28112445

RESUMO

S-adenosylmethionine (AdoMet) is synthesized by methionine adenosyltransferase (MAT), and plays an essential role in ethylene biosynthesis and other methylation reactions. Despite increasing knowledge of MAT regulation at transcriptional levels, how MAT is post-translationally regulated remains unknown in plant cells. Phosphorylation is an important post-translational modification for regulating the activity of enzymes, protein function and signaling transduction. Using molecular and biochemical approaches, we have identified the phosphorylation of MAT proteins by calcium-dependent protein kinase (CPK28). Phenotypically, both MAT2-overexpressing transgenic plants and cpk28 mutants display short hypocotyls and ectopic lignifications. Their shortened hypocotyl phenotypes are caused by ethylene overproduction and rescued by ethylene biosynthesis inhibitor aminoethoxyvinylglycine treatment. Genetic evidence reveals that MAT2 mutation restores the phenotype of ectopic lignification in CPK28-deficient plants. We find that total MAT proteins and AdoMet are increased in cpk28 mutants, but decreased in CPK28-overexpressing seedlings. We also find that MATs in OE::CPK28 are degraded through the 26S proteasome pathway. Our work suggests that CPK28 targets MATs (MAT1, MAT2 and MAT3) for degradation by the 26S proteasome pathway, and thus affects ethylene biosynthesis and lignin deposition in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Etilenos/biossíntese , Lignina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Quinases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Quinases/genética , Processamento de Proteína Pós-Traducional/genética , Processamento de Proteína Pós-Traducional/fisiologia
20.
Adv Funct Mater ; 28(15)2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-31354399

RESUMO

We report a temperature-regulated system for the controlled release of nerve growth factor (NGF) to promote neurite outgrowth. The system is based upon microparticles fabricated using coaxial electrospray, with the outer solution containing a phase-change material (PCM) and the inner solution encompassing payload(s). When the temperature is kept below the melting point of the PCM, there is no release due to the extremely slow diffusion through a solid matrix. Upon increasing the temperature to slightly pass the melting point, the encapsulated payload(s) can be readily released from the melted PCM. By leveraging the reversibility of the phase transition, the payload(s) can be released in a pulsatile mode through on/off heating cycles. The controlled release system is evaluated for potential use in neural tissue engineering by sandwiching the microparticles, co-loaded with NGF and a near-infrared dye, between two layers of electrospun fibers to form a tri-layer construct. Upon photothermal heating with a near-infrared laser, the NGF is released with well-preserved bioactivity to promote neurite outgrowth. By choosing different combinations of PCM, biological effector, and scaffolding material, this controlled release system can be applied to a wide variety of biomedical applications.

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