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1.
Mol Cell ; 78(4): 714-724.e5, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32353258

RESUMO

Nonrandom DNA segregation (NDS) is a mitotic event in which sister chromatids carrying the oldest DNA strands are inherited exclusively by one of the two daughter cells. Although this phenomenon has been observed across various organisms, the mechanism and physiological relevance of this event remain poorly defined. Here, we demonstrate that DNA replication stress can trigger NDS in human cells. This biased inheritance of old template DNA is associated with the asymmetric DNA damage response (DDR), which derives at least in part from telomeric DNA. Mechanistically, we reveal that the ATR/CHK1 signaling pathway plays an essential role in mediating NDS. We show that this biased segregation process leads to cell-cycle arrest and cell death in damaged daughter cells inheriting newly replicated DNA. These data therefore identify a key role for NDS in the maintenance of genomic integrity within cancer cell populations undergoing replication stress due to oncogene activation.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Cromossomos Humanos/genética , Dano ao DNA , Replicação do DNA , Mitose , Proteínas Mutadas de Ataxia Telangiectasia/genética , Quinase 1 do Ponto de Checagem/genética , Segregação de Cromossomos , Células HeLa , Humanos , Transdução de Sinais
2.
J Immunol ; 213(3): 257-267, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856632

RESUMO

Psoriasis is a common inflammatory skin disorder with no cure. Mesenchymal stem cells (MSCs) have immunomodulatory properties for psoriasis, but the therapeutic efficacies varied, and the molecular mechanisms were unknown. In this study, we improved the efficacy by enhancing the immunomodulatory effects of umbilical cord-derived MSCs (UC-MSCs). UC-MSCs stimulated by TNF-α and IFN-γ exhibited a better therapeutic effect in a mouse model of psoriasis. Single-cell RNA sequencing revealed that the stimulated UC-MSCs overrepresented a subpopulation expressing high tryptophanyl-tRNA synthetase 1 (WARS1). WARS1-overexpressed UC-MSCs treat psoriasis-like skin inflammation more efficiently than control UC-MSCs by restraining the proinflammatory macrophages. Mechanistically, WARS1 maintained a RhoA-Akt axis and governed the immunomodulatory properties of UC-MSCs. Together, we identify WARS1 as a master regulator of UC-MSCs with enhanced immunomodulatory capacities, which paves the way for the directed modification of UC-MSCs for escalated therapeutic efficacy.


Assuntos
Imunomodulação , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/imunologia , Animais , Camundongos , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Triptofano-tRNA Ligase/genética , Psoríase/imunologia , Psoríase/terapia , Modelos Animais de Doenças , Análise de Célula Única , Análise de Sequência de RNA , Cordão Umbilical/citologia , Cordão Umbilical/imunologia , Camundongos Endogâmicos C57BL , Células Cultivadas
3.
BMC Psychiatry ; 24(1): 340, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715019

RESUMO

PURPOSE: To explore the mediating effect of hope in the relationships between social support and self-esteem with psychological resilience among patients with stroke survivors in early rehabilitation. METHODS: A cross-sectional study design was adopted. Data from a cross-sectional survey of 210 patients undergoing early stroke rehabilitation were analyzed using structural equation modeling. The variables of interest were measured using the Connor Davidson Resilience Scale, the Social Support Rating Scale, the Herth Hope Index, and the Self-Esteem Scale. This article reports according to the STROBE checklist. RESULTS: A positive relationship was found between social support and psychological resilience (ß1 = 0.548), which was mediated by hope (ß2 = 0.114), and social support had significant direct effect on resilience (ß3 = 0.434). A positive relationship was also found between self-esteem and psychological resilience (ß4 = 0.380), which was mediated by hope (ß5 = 0.200), and self-esteem had significant direct effect on resilience (ß6 = 0.179). CONCLUSION: According to the results of this study, some strategies can be incorporated into the rehabilitation process to enhance psychological resilience, such as cultivating individual personality characteristics and improving patients' social relationships. In the future, we need to explore methods for improving psychological resilience among patients with stroke in combination with their risk factors to improve their quality of life and reduce the incidence of post-stroke depression.


Assuntos
Esperança , Resiliência Psicológica , Autoimagem , Apoio Social , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Estudos Transversais , Pessoa de Meia-Idade , Idoso , Acidente Vascular Cerebral/psicologia , Reabilitação do Acidente Vascular Cerebral/psicologia , Adulto
4.
J Pers ; 92(2): 530-547, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37208805

RESUMO

INTRODUCTION: Humanistic psychologists have conceptualized a tendency among humans to experience continual open-ended psychological growth. This study aims to measure the rate at which one grows psychologically using a novel growth curve modeling approach that addresses previous limitations. We also examine the effects of nine potential contributors to growth identified from the literature. METHOD: Throughout the freshman year, 556 college students responded six times. Increments of growth were added up to create cumulative growth, which was then fit to a growth curve model to produce an estimate of the growth rate. The growth rate was then regressed on the Time 1 predictors to examine their unique effects. RESULTS: Models fit well. Five predictors significantly predicted the growth rate after controlling for the average of other predictors. When all predictors were entered simultaneously, three predictors (hope, meaning, and personal growth initiative) showed significant unique effects. The growth rate predicted well-being and satisfaction at Time 6. CONCLUSION: We successfully measured the rate of psychological growth and examined its antecedents. Follow-up analyses suggested that the predictors not showing unique effects may indirectly predict growth rates via the proximal role of the three significant predictors, an idea that awaits future corroboration using within-individual designs.


Assuntos
Desenvolvimento Psicológico , Estudantes , Humanos , Estudos Longitudinais
5.
J Sci Food Agric ; 104(9): 4977-4988, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38567804

RESUMO

BACKGROUND: As the major protein (approximately 36%) in rice bran, globulin exhibits excellent foaming and emulsifying properties, endowing its useful application as a foaming and emulsifying agent in the food industry. However, the low water solubility restricts its commercial potential in industrial applications. The present study aimed to improve this protein's processing and functional properties. RESULTS: A novel covalent complex was fabricated by a combination of the Maillard reaction and alkaline oxidation using rice bran globulin (RBG), chitooligosaccharide (C), quercetin (Que) and resveratrol (Res). The Maillard reaction improved the solubility, emulsifying and foaming properties of RBG. The resultant glycosylated protein was covalently bonded with quercetin and resveratrol to form a (RBG-C)-Que-Res complex. (RBG-C)-Que-Res exhibited higher thermal stability and antioxidant ability than the native protein, binary globulin-chitooligosaccharide or ternary globulin-chitooligosaccharide-polyphenol (only containing quercetin or resveratrol) conjugates. (RBG-C)-Que-Res exerted better cytoprotection against the generation of malondialdehyde and reactive oxygen species in HepG2 cells, which was associated with increased activities of antioxidative enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) through upregulated genes SOD1, CAT, GPX1 (i.e. gene for glutathione peroxidase-1), GCLM (i.e. gene for glutamate cysteine ligase modifier subunit), SLC1A11 (i.e. gene for solute carrier family 7, member 11) and SRXN1 (i.e. gene for sulfiredoxin-1). The anti-apoptotic effect of (RBG-C)-Que-Res was confirmed by the downregulation of caspase-3 and p53 and the upregulation of B-cell lymphoma-2 gene expression. CONCLUSION: The present study highlights the potential of (RBG-C)-Que-Res conjugates as functional ingredients in healthy foods. © 2024 Society of Chemical Industry.


Assuntos
Antioxidantes , Quitosana , Oligossacarídeos , Oryza , Quercetina , Resveratrol , Humanos , Quercetina/química , Quercetina/análogos & derivados , Oryza/química , Oligossacarídeos/química , Resveratrol/química , Resveratrol/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Quitosana/química , Células Hep G2 , Quitina/química , Quitina/análogos & derivados , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Reação de Maillard , Catalase/metabolismo , Catalase/genética , Glutationa Peroxidase/metabolismo , Glutationa Peroxidase/genética
6.
Ann Bot ; 131(1): 215-228, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35639931

RESUMO

BACKGROUND AND AIMS: Tandemly repeated DNA and transposable elements represent most of the DNA in higher plant genomes. High-throughput sequencing allows a survey of the DNA in a genome, but whole-genome assembly can miss a substantial fraction of highly repeated sequence motifs. Chrysanthemum nankingense (2n = 2x = 18; genome size = 3.07 Gb; Asteraceae), a diploid reference for the many auto- and allopolyploids in the genus, was considered as an ancestral species and serves as an ornamental plant and high-value food. We aimed to characterize the major repetitive DNA motifs, understand their structure and identify key features that are shaped by genome and sequence evolution. METHODS: Graph-based clustering with RepeatExplorer was used to identify and classify repetitive motifs in 2.14 millions of 250-bp paired-end Illumina reads from total genomic DNA of C. nankingense. Independently, the frequency of all canonical motifs k-bases long was counted in the raw read data and abundant k-mers (16, 21, 32, 64 and 128) were extracted and assembled to generate longer contigs for repetitive motif identification. For comparison, long terminal repeat retrotransposons were checked in the published C. nankingense reference genome. Fluorescent in situ hybridization was performed to show the chromosomal distribution of the main types of repetitive motifs. KEY RESULTS: Apart from rDNA (0.86 % of the total genome), a few microsatellites (0.16 %), and telomeric sequences, no highly abundant tandem repeats were identified. There were many transposable elements: 40 % of the genome had sequences with recognizable domains related to transposable elements. Long terminal repeat retrotransposons showed widespread distribution over chromosomes, although different sequence families had characteristic features such as abundance at or exclusion from centromeric or subtelomeric regions. Another group of very abundant repetitive motifs, including those most identified as low-complexity sequences (9.07 %) in the genome, showed no similarity to known sequence motifs or tandemly repeated elements. CONCLUSIONS: The Chrysanthemum genome has an unusual structure with a very low proportion of tandemly repeated sequences (~1.02 %) in the genome, and a high proportion of low-complexity sequences, most likely degenerated remains of transposable elements. Identifying the presence, nature and genomic organization of major genome fractions enables inference of the evolutionary history of sequences, including degeneration and loss, critical to understanding biodiversity and diversification processes in the genomes of diploid and polyploid Chrysanthemum, Asteraceae and plants more widely.


Assuntos
Chrysanthemum , Retroelementos , Hibridização in Situ Fluorescente , Chrysanthemum/genética , Elementos de DNA Transponíveis , Sequências Repetitivas de Ácido Nucleico , Genômica , Genoma de Planta , Plantas/genética , Evolução Molecular
7.
Int J Mol Sci ; 24(19)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37833913

RESUMO

The APETALA2/ethylene-responsive transcription factor (AP2/ERF) family has been extensively investigated because of its significant involvement in plant development, growth, fruit ripening, metabolism, and plant stress responses. To date, there has been little investigation into how the AP2/ERF genes influence flower formation and anthocyanin biosynthesis in Lycoris. Herein, 80 putative LrAP2/ERF transcription factors (TFs) with complete open reading frames (ORFs) were retrieved from the Lycoris transcriptome sequence data, which could be divided into five subfamilies dependent on their complete protein sequences. Furthermore, our findings demonstrated that genes belonging to the same subfamily had structural similarities and conserved motifs. LrAP2/ERF genes were analyzed for playing an important role in plant growth, water deprivation, and flower formation by means of gene ontology (GO) enrichment analysis. The expression pattern of the LrAP2/ERF genes differed across tissues and might be important for Lycoris growth and flower development. In response to methyl jasmonate (MeJA) exposure and drought stress, the expression of each LrAP2/ERF gene varied across tissues and time. Moreover, a total of 20 anthocyanin components were characterized using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) analysis, and pelargonidin-3-O-glucoside-5-O-arabinoside was identified as the major anthocyanin aglycone responsible for the coloration of the red petals in Lycoris. In addition, we mapped the relationships between genes and metabolites and found that LrAP2/ERF16 is strongly linked to pelargonidin accumulation in Lycoris petals. These findings provide the basic conceptual groundwork for future research into the molecular underpinnings and regulation mechanisms of AP2/ERF TFs in anthocyanin accumulation and Lycoris floral development.


Assuntos
Lycoris , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Lycoris/genética , Antocianinas , Espectrometria de Massas em Tandem , Família Multigênica , Etilenos , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia
8.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834753

RESUMO

Dioscorea alata L. (Dioscoreaceae), commonly known as greater yam, water yam, or winged yam, is a popular tuber vegetable/food crop worldwide, with nutritional, health, and economical importance. China is an important domestication center of D. alata, and hundreds of cultivars (accessions) have been established. However, genetic variations among Chinese accessions remain ambiguous, and genomic resources currently available for the molecular breeding of this species in China are very scarce. In this study, we generated the first pan-plastome of D. alata, based on 44 Chinese accessions and 8 African accessions, and investigated the genetic variations, plastome evolution, and phylogenetic relationships within D. alata and among members of the section Enantiophyllum. The D. alata pan-plastome encoded 113 unique genes and ranged in size from 153,114 to 153,161 bp. A total of four whole-plastome haplotypes (Haps I-IV) were identified in the Chinese accessions, showing no geographical differentiation, while all eight African accessions shared the same whole-plastome haplotype (Hap I). Comparative genomic analyses revealed that all four whole plastome haplotypes harbored identical GC content, gene content, gene order, and IR/SC boundary structures, which were also highly congruent with other species of Enantiophyllum. In addition, four highly divergent regions, i.e., trnC-petN, trnL-rpl32, ndhD-ccsA, and exon 3 of clpP, were identified as potential DNA barcodes. Phylogenetic analyses clearly separated all the D. alata accessions into four distinct clades corresponding to the four haplotypes, and strongly supported that D. alata was more closely related to D. brevipetiolata and D. glabra than D. cirrhosa, D. japonica, and D. polystachya. Overall, these results not only revealed the genetic variations among Chinese D. alata accessions, but also provided the necessary groundwork for molecular-assisted breeding and industrial utilization of this species.


Assuntos
Dioscorea , Filogenia , Genômica , Haplótipos , Variação Genética
9.
Int J Mol Sci ; 24(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36768747

RESUMO

Lycoris radiata, belonging to the Amaryllidaceae family, is a well-known Chinese traditional medicinal plant and susceptible to many stresses. WRKY proteins are one of the largest families of transcription factors (TFs) in plants and play significant functions in regulating physiological metabolisms and abiotic stress responses. The WRKY TF family has been identified and investigated in many medicinal plants, but its members and functions are not identified in L. radiata. In this study, a total of 31 L. radiata WRKY (LrWRKY) genes were identified based on the transcriptome-sequencing data. Next, the LrWRKYs were divided into three major clades (Group I-III) based on the WRKY domains. A motif analysis showed the members within same group shared a similar motif component, indicating a conservational function. Furthermore, subcellular localization analysis exhibited that most LrWRKYs were localized in the nucleus. The expression pattern of the LrWRKY genes differed across tissues and might be important for Lycoris growth and flower development. There were large differences among the LrWRKYs based on the transcriptional levels under drought stress and MeJA treatments. Moreover, a total of 18 anthocyanin components were characterized using an ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) analysis and pelargonidin-3-O-glucoside-5-O-arabinoside as well as cyanidin-3-O-sambubioside were identified as the major anthocyanin aglycones responsible for the coloration of the red petals in L. radiata. We further established a gene-to-metabolite correlation network and identified LrWRKY3 and LrWRKY27 significant association with the accumulation of pelargonidin-3-O-glucoside-5-O-arabinoside in the Lycoris red petals. These results provide an important theoretical basis for further exploring the molecular basis and regulatory mechanism of WRKY TFs in anthocyanin biosynthesis and in response to drought stress and MeJA treatment.


Assuntos
Lycoris , Lycoris/metabolismo , Proteínas de Plantas/metabolismo , Secas , Antocianinas , Espectrometria de Massas em Tandem , Glucosídeos , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico/genética , Filogenia
10.
Angew Chem Int Ed Engl ; 62(40): e202309922, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37578857

RESUMO

The Suzuki-Miyaura cross-coupling is one of the most important and powerful methods for constructing C-C bonds. However, the protodeboronation of arylboronic acids hinder the development of Suzuki-Miyaura coupling in the precise synthesis of conjugated polymers (CPs). Here, an anhydrous room temperature Suzuki-Miyaura cross-coupling reaction between (hetero)aryl boronic esters and aryl sulfides was explored, of which universality was exemplified by thirty small molecules and twelve CPs. Meanwhile, the mechanistic studies involving with capturing four coordinated borate intermediate revealed the direct transmetalation of boronic esters in the absence of H2 O suppressing the protodeboronation. Additionally, the room temperature reaction significantly reduced the homocoupling defects and enhanced the optoelectronic properties of the CPs. In all, this work provides a green protocol to synthesize alternating CPs.

11.
Angew Chem Int Ed Engl ; 62(41): e202306307, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37340517

RESUMO

The direct arylation polycondensation (DArP) has become one of the most important methods to construct conjugated polymers (CPs). However, the homocoupling side-reactions of aryl halides and the low regioseletive reactivities of unfunctionalized aryls hinder the development of DArP. Here, an efficient Pd and Cu co-catalyzed DArP was developed via inert C-S bond cleavage of aryl thioethers, of which robustness was exemplified by over twenty conjugated polymers (CPs), including copolymers, homopolymers, and random polymers. The capture of oxidative addition intermediate together with experimental and theoretic results suggested the important role of palladium (Pd) and copper (Cu) co-catalysis with a bicyclic mechanism. The studies of NMR, molecular weights, trap densities, two-dimensional grazing-incidence wide-angle X-ray scattering (2D-GIWAXS), and the charge transport mobilities revealed that the homocoupling reactions were significantly suppressed with high regioselectivity of unfunctionalized aryls, suggesting this method is an excellent choice for synthesizing high performance CPs.

12.
J Exp Bot ; 73(1): 197-212, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34453430

RESUMO

Embryo abortion often occurs during distant hybridization events. Apetala 2/ethylene-responsive factor (AP2/ERF) proteins are key transcription factor (TF) regulators of plant development and stress resistance, but their roles in hybrid embryo development are poorly understood. In this study, we isolated a novel AP2/ERF TF, CmERF12, from chrysanthemum and show that it adversely affects embryo development during distant hybridization. Transcriptome and real-time quantitative PCR demonstrate that CmERF12 is expressed at significantly higher levels in aborted ovaries compared with normal ones. CmERF12 localizes to the cell nucleus and contains a conserved EAR motif that mediates its transcription repressor function in yeast and plant cells. We generated artificial microRNA (amiR) CmERF12 transgenic lines of Chrysanthemum morifolium var. 'Yuhualuoying' and conducted distant hybridization with the wild-type tetraploid, Chrysanthemum nankingense, and found that CmERF12-knock down significantly promoted embryo development and increased the seed-setting rates during hybridization. The expression of various genes related to embryo development was up-regulated in developing ovaries from the cross between female amiR-CmERF12 C. morifolium var. 'Yuhualuoying'× male C. nankingense. Furthermore, CmERF12 directly interacted with CmSUF4, which is known to affect flower development and embryogenesis, and significantly reduced its ability to activate its target gene CmEC1 (EGG CELL1). Our study provides a novel method to overcome barriers to distant hybridization in plants and reveals the mechanism by which CmERF12 negatively affects chrysanthemum embryo development.


Assuntos
Chrysanthemum , Chrysanthemum/genética , Chrysanthemum/metabolismo , Desenvolvimento Embrionário , Regulação da Expressão Gênica de Plantas , Hibridização Genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo
13.
Langmuir ; 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35613042

RESUMO

Development of graphene-organic hybrid electronics is one of the most promising directions for next-generation electronic materials. However, it remains challenging to understand the graphene-organic semiconductor interactions right at the interface, which is key to designing hybrid electronics. Herein, we study the influence of graphene on the multiscale morphology of solution-processed monolayers of conjugated polymers (PII-2T, DPP-BTz, DPP2T-TT, and DPP-T-TMS). The strong interaction between graphene and PII-2T was manifested in the high fiber density and high film coverage of monolayer films deposited on graphene compared to plasma SiO2 substrates. The monolayer films on graphene also exhibited a higher relative degree of crystallinity and dichroic ratio or polymer alignment, i.e., higher degree of order. Raman spectroscopy revealed the increased backbone planarity of the conjugated polymers upon deposition on graphene as well as the existence of electronic interaction across the interface. This speculation was further substantiated by the results of photoelectron spectroscopy (XPS and UPS) of PII-2T, which showed a decrease in binding energy of several atomic energy levels, movement of the Fermi level toward HOMO, and an increase in work function, all of which indicate p-doping of the polymer. Our results provide a new level of understanding on graphene-polymer interactions at nanoscopic interfaces and the consequent impact on multiscale morphology, which will aid in the design of efficient graphene-organic hybrid electronics.

14.
J Chem Inf Model ; 62(22): 5780-5793, 2022 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-36330712

RESUMO

Nattokinase (NK) is a serine protease with a potent thrombolytic activity that possesses multiple cardiovascular disease (CVD) preventative and treatment activities. In light of its advanced beneficial cardiovascular effects and its nature as a serine protease, characterizing its biological substrates is essential for informing and ultimately delineating the molecular mechanism of its thrombolytic and anticoagulant activities that will unlock the powerful strategic design of effective therapies for CVDs. Given the efficacy of NK to break the vicious loop between inflammation, oxidative stress, and thrombosis, and the extensive role of thrombin in the loop, a stepwise computational strategy was developed to investigate the cleavage events of NK, including both a protein-protein complex model for protein substrate recognition and a protease-peptide complex model for the cleavage site identification, whereby their contact region was sited to allow for the prediction of the corresponding cleavage site that was successfully verified by both mass spectrometry (MS)-based N-terminal sequencing and various functional assays. Collectively, thrombin was predicted and identified to be a novel biological substrate of NK, which expanded the comprehensive antithrombus mechanism of NK via breaking the vicious loop between inflammation, oxidative stress, and thrombosis. This study not only provided insight into the interaction characteristics between NK and its hydrolytic substrate for a better understanding toward its catalytic mechanism but also developed a comprehensive computational strategy to elucidate the proteolytic targets of NK for the breakthrough of feature drug development.


Assuntos
Trombina , Trombose , Humanos , Trombina/metabolismo , Subtilisinas/química , Trombose/tratamento farmacológico , Serina Endopeptidases/metabolismo , Inflamação , Especificidade por Substrato
15.
J Nat Prod ; 85(4): 1174-1179, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35324187

RESUMO

A phytochemical investigation on the aerial parts of Euphorbia helioscopia resulted in the isolation of 27 macrocyclic diterpenoids, including three previously unreported lathyrane derivatives, euphohelioscopoids A-C (1-3). Their structures were elucidated by spectroscopic data interpretation. Three jatrophanes, euphoscopin C (4), euphorbiapene D (6), and euphoheliosnoid A (5), showed cytotoxicity against a paclitaxel-resistant A549 human lung cancer cell line with IC50 values of 6.9, 7.2, and 9.5 µM, respectively, but were inactive against the parent A549 human lung cancer cell line (IC50 > 10 µM). It was found that jatrophanes with a benzoyloxy or a nicotinoyloxy substituent at C-7 showed more potent cytotoxic activity than their analogues containing acetyloxy and hydroxy groups at this position.


Assuntos
Diterpenos , Euphorbia , Neoplasias Pulmonares , Linhagem Celular , Diterpenos/química , Diterpenos/farmacologia , Euphorbia/química , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Estrutura Molecular , Paclitaxel/farmacologia
16.
Int J Mol Sci ; 23(22)2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36430515

RESUMO

The transition from vegetative to reproductive growth is important for controlling the flowering of Lycoris radiata. However, the genetic control of this complex developmental process remains unclear. In this study, 18 shoot apical meristem (SAM) samples were collected from early-, mid- and late-flowering populations during floral bud differentiation. The histological analysis of paraffin sections showed that the floral bud differentiation could be divided into six stages; the differentiation time of the early group was earlier than that of the middle and late groups, and the late group was the latest. In different populations, some important differential genes affecting the flowering time were identified by transcriptome profiles of floral bud differentiation samples. Weighted gene co-expression network analysis (WGCNA) was performed to enrich the gene co-expression modules of diverse flowering time populations (FT) and floral bud differentiation stages (ST). In the MEyellow module, five core hub genes were identified, including CO14, GI, SPL8, SPL9, and SPL15. The correlation network of hub genes showed that they interact with SPLs, AP2, hormone response factors (auxin, gibberellin, ethylene, and abscisic acid), and several transcription factors (MADS-box transcription factor, bHLH, MYB, and NAC3). It suggests the important role of these genes and the complex molecular mechanism of floral bud differentiation and flowering time in L. radiata. These results can preliminarily explain the molecular mechanism of floral bud differentiation and provide new candidate genes for the flowering regulation of Lycoris.


Assuntos
Lycoris , Reprodução , Redes Reguladoras de Genes , Giberelinas , Ácido Abscísico , Fatores de Transcrição/genética
17.
Angew Chem Int Ed Engl ; 61(16): e202115969, 2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35099844

RESUMO

The Stille cross-coupling polymerization is one of the most efficient synthetic methods for donor-acceptor (D-A) type π-conjugated polymers (CPs). Nevertheless, thermal-activation Stille polymerization readily produced homocoupling defects, resulting in batch-to-batch variations in copolymers quality and deteriorating the device performance of electronics and optoelectronics. Here, a room-temperature Stille-type polymerization was developed, the utility and generality of which were demonstrated by synthesis of twelve D-A CPs with high molecular weights. Importantly, the resultant copolymers possessed no homocoupling (hc) structural defects, while hc reactions were observed in the thermal-activation Stille reactions. Thus, the organic field-effect transistors (OFETs) based on the former exhibited twofold higher charge transport mobility (2.10 cm2  V-1 s-1 ), since it possessed stronger crystallinity and lower trap density of states (tDOS).

18.
Angew Chem Int Ed Engl ; 61(51): e202214147, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36328976

RESUMO

Strategies on the construction of enantiomerically pure silicon-stereogenic silanes generally relies on desymmetrization of prochiral and symmetric substrates. However, dynamic kinetic asymmetric transformations of organosilicon compounds have remained underdeveloped and unforeseen owing to a lack of an effective method for deracemization of the static silicon stereocenters. Here we report the first Rh-catalyzed dynamic kinetic asymmetric intramolecular hydrosilylation (DyKAH) with "silicon-centered" racemic hydrosilanes that enables the facile preparation of silicon-stereogenic benzosiloles in good yields and excellent enantioselectivities. The special rhodium catalyst controlled by non-diastereopure-type mixed phosphine-phosphoramidite ligand with axial chirality and multiple stereocenters can induce enantioselectivity efficiently in this novel DyKAH reaction. Density functional theory (DFT) calculations suggest that the amide moiety in chiral ligand plays important role in facilitating the SN 2 substitution of chloride ion to realize the chiral inversion of silicon center.

19.
BMC Plant Biol ; 21(1): 432, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556053

RESUMO

BACKGROUND: MYB transcription factors, comprising one of the largest transcription factor families in plants, play many roles in secondary metabolism, especially in anthocyanin biosynthesis. However, the functions of the PdeMYB transcription factor in colored-leaf poplar remain elusive. RESULTS: In the present study, genome-wide characterization of the PdeMYB genes in colored-leaf poplar (Populus deltoids) was conducted. A total of 302 PdeMYB transcription factors were identified, including 183 R2R3-MYB, five R1R2R3-MYB, one 4R-MYB, and 113 1R-MYB transcription factor genes. Genomic localization and paralogs of PdeMYB genes mapped 289 genes on 19 chromosomes, with collinearity relationships among genes. The conserved domain, gene structure, and evolutionary relationships of the PdeMYB genes were also established and analyzed. The expression levels of PdeMYB genes were obtained from previous data in green leaf poplar (L2025) and colored leaf poplar (QHP) as well as our own qRT-PCR analysis data in green leaf poplar (L2025) and colored leaf poplar (CHP), which provide valuable clues for further functional characterization of PdeMYB genes. CONCLUSIONS: The above results provide not only comprehensive insights into the structure and functions of PdeMYB genes but also provide candidate genes for the future improvement of leaf colorization in Populus deltoids.


Assuntos
Antocianinas/biossíntese , Antocianinas/genética , Arabidopsis/genética , Pigmentação/genética , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Populus/genética , Fatores de Transcrição/genética , Regulação da Expressão Gênica de Plantas , Variação Genética , Estudo de Associação Genômica Ampla , Genômica , Genótipo , Filogenia , Plantas Geneticamente Modificadas
20.
BMC Cancer ; 21(1): 915, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384377

RESUMO

BACKGROUND: Intracranial hemangiopericytoma is a rare disease and surgery is the mainstay treatment. Although postoperative adjuvant radiotherapy is often used, there are no reports comparing different radiotherapy techniques. The purpose of this study is to analyze the impact of post-operative radiotherapy and different radiotherapy technique on the results in patients with intracranial hemangiopericytoma (HPC). METHODS: We retrospectively reviewed 66 intracranial HPC patients treated between 1999 and 2019 including 29 with surgery followed by radiotherapy (11 with intensity-modulated radiotherapy (IMRT) and 18 with stereotactic radiosurgery (SRS)) and 37 with surgery alone. Chi-square test was used to compare the clinical characteristic between the groups. The Kaplan-Meier method was used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariate Cox proportional hazards models were used to examine prognostic factors of survival. We also underwent a matched-pair analysis by using the propensity score method. RESULTS: The crude local control rates were 58.6% in the surgery plus post-operative radiotherapy group (PORT) and 67.6% in the surgery alone group (p = 0.453). In the subgroup analysis of the PORT patients, local controls were 72.7% in the IMRT group and 50% in the SRS group (p = 0.228). The median OS in the PORT and surgery groups were 122 months and 98 months, respectively (p = 0.169). The median RFS was 96 months in the PORT group and 72 months in the surgery alone group (p = 0.714). Regarding radiotherapy technique, the median OS and RFS of the SRS group were not significantly different from those in the IMRT group (p = 0.256, 0.960). The median RFS were 112 and 72 months for pathology grade II and III patients, respectively (p = 0.001). Propensity score matching did not change the observed results. CONCLUSION: In this retrospective analysis, PORT did not improve the local control rates nor the survivals. The local control rates after IMRT and SRS were similar even though the IMRT technique had a much higher biological dose compared with the SRS technique.


Assuntos
Neoplasias Encefálicas/radioterapia , Hemangiopericitoma/radioterapia , Cuidados Pós-Operatórios , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/mortalidade , Terapia Combinada , Feminino , Hemangiopericitoma/diagnóstico , Hemangiopericitoma/mortalidade , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Modelos de Riscos Proporcionais , Radiocirurgia , Radioterapia de Intensidade Modulada , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
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