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1.
FASEB J ; 38(11): e23693, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38809685

RESUMO

N6-methylated adenosine (m6A) is a crucial RNA modification in eukaryotes, particularly in cancer. However, its role in cervical cancer (CC) is unclear. We aimed to elucidate the part of m6A in CC by analyzing methyltransferase-like 3 (METTL3) expression, identifying downstream targets, and exploring the underlying mechanism. We assessed METTL3 expression in CC using western blotting, quantitative polymerase chain reaction (qPCR), and immunohistochemistry. In vitro and in vivo experiments examined METTL3's role in CC. We employed RNA sequencing, methylated RNA immunoprecipitation sequencing, qPCR, and RNA immunoprecipitation qPCR to explore METTL3's mechanism in CC. METTL3 expression was upregulated in CC, promoting cell proliferation and metastasis. METTL3 knockdown inhibited human cervical cancer by inactivating AKT/mTOR signaling pathway. METTL3-mediated m6A modification was observed in CC cells, targeting phosphodiesterase 3A (PDE3A). METTL3 catalyzed m6A modification on PDE3A mRNA through YTH domain family protein 3 (YTHDF3). Our study indicated the mechanism of m6A modification in CC and suggested the METTL3/YTHDF3/PDE3A axis as a potential clinical target for CC treatment.


Assuntos
Adenosina , Proliferação de Células , Metiltransferases , Neoplasias do Colo do Útero , Animais , Feminino , Humanos , Camundongos , Adenosina/análogos & derivados , Adenosina/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Metiltransferases/metabolismo , Metiltransferases/genética , Camundongos Endogâmicos BALB C , Camundongos Nus , Transdução de Sinais , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Metilação de RNA/genética
2.
Small ; 20(28): e2311129, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38319033

RESUMO

Constructing concentration differences between anions and cations at the ends of an ionic conductor is an effective strategy in electricity generation for powering wearable devices. Temperature gradient or salinity gradient is the driving force behind such devices. But their corresponding power generation devices are greatly limited in actual application due to their complex structure and harsh application conditions. In this study, a novel ionic concentration gradient electric generator based on the evaporation difference of the electrolyte is proposed. The device can be constructed without the need for semipermeable membranes, and operation does not need to build a temperature difference. As a demonstration, a PVA-Na ionic hydrogel is prepared as an electrolyte for the device and achieved a thermovoltage of more than 200 mV and an energy density of 77.94 J m-2 at 323 K. Besides, the device exhibits the capability to sustain a continuous voltage output for a duration exceeding 1500 min, as well as enabling charging and discharging cycles for 100 iterations. For practical applications, a module comprising 16 sub-cells is constructed and successfully utilized to directly power a light-emitting diode. Wearable devices and their corresponding cell modules are also developed to recycle body heat.

3.
Phys Chem Chem Phys ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39441659

RESUMO

Salt-free reductants have been extensively studied in the plutonium uranium reduction extraction (PUREX) process for Np(VI) reduction. Hydroxylamine derivatives as a class of promising salt-free reductants can reduce Np(VI) to Np(V) in nitric acid solution. The reduction reaction and kinetic behavior of Np(VI) to Np(V) by diethylhydroxylamine (DEHA) were studied experimentally. Herein, we explored the reduction mechanism of Np(VI) by DEHA in aqueous solution using scalar-relativistic density functional theory. Four stages are included in the process of Np(VI) reduction to Np(V) by DEHA. The intermediate C2H5N(O)C2H4 is hydrolyzed to C2H5NHOH. The third and fourth stages of Np(VI) reduction are via two pathways due to different H atoms participating successively in the reduction process. The largest energy barrier for the four Np(VI) reduction processes is 12.3 kcal mol-1 for the third stage of Pathway I, consistent with the experimental observations. The Np-Oyl bond distances and spin density on Np elucidate the reduction essence including outer-sphere electron transfer or hydrogen atom transfer. The analyses of bonding nature reveal the bonding evolution during the reduction process. This work elucidates the reduction mechanism of Np(VI) by DEHA and provides new insights into the reduction of Np(VI) by hydroxylamine derivatives.

4.
J Asian Nat Prod Res ; 26(2): 189-194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882670

RESUMO

Two new baccharane triterpenes, 17,24-epoxy-23-en-baccharan-3-one (1) and 17,24(S)-epoxy-25-en-21-hydroxy-baccharan-3-one (2) were isolated from Rhus chinensis Mill. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy and X-ray diffraction analysis.


Assuntos
Rhus , Triterpenos , Triterpenos Pentacíclicos , Rhus/química , Triterpenos/farmacologia , Triterpenos/química , Extratos Vegetais , Espectroscopia de Ressonância Magnética , Estrutura Molecular
5.
Plant J ; 110(5): 1237-1254, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35384101

RESUMO

A runner, as an elongated branch, develops from the axillary bud (AXB) in the leaf axil and is crucial for the clonal propagation of cultivated strawberry (Fragaria × ananassa Duch.). Runner formation occurs in at least two steps: AXB initiation and AXB outgrowth. HANABA TARANU (HAN ) encodes a GATA transcription factor that affects AXB initiation in Arabidopsis and promotes branching in grass species, but the underlying mechanism is largely unknown. Here, the function of a strawberry HAN homolog FaHAN in runner formation was characterized. FaHAN transcripts can be detected in the leaf axils. Overexpression (OE) of FaHAN increased the number of runners, mainly by enhancing AXB outgrowth, in strawberry. The expression of the strawberry homolog of BRANCHED1 , a key inhibitor of AXB outgrowth in many plant species, was significantly downregulated in the AXBs of FaHAN -OE lines, whereas the expression of the strawberry homolog of SHOOT MERISTEMLESS, a marker gene for AXB initiation in Arabidopsis, was upregulated. Moreover, several genes of gibberellin biosynthesis and cytokinin signaling pathways were activated, whereas the auxin response pathway genes were repressed. Further assays indicated that FaHAN could be directly activated by FaNAC2, the overexpression of which in strawberry also increased the number of runners. The silencing of FaNAC2 or FaHAN inhibited AXB initiation and led to a higher proportion of dormant AXBs, confirming their roles in the control of runner formation. Taken together, our results revealed a FaNAC2-FaHAN pathway in the control of runner formation and have provided a means to enhance the vegetative propagation of cultivated strawberry.


Assuntos
Arabidopsis , Fragaria , Arabidopsis/metabolismo , Fragaria/genética , Fragaria/metabolismo , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos/metabolismo , Brotos de Planta/metabolismo
6.
J Gen Virol ; 104(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802334

RESUMO

The coat protein (CP) of plant viruses generally has multiple functions involving infection, replication, movement and pathogenicity. Functions of the CP of prunus necrotic ringspot virus (PNRSV), the causal agent of several threatening diseases of Prunus fruit trees, are poorly studied. Previously, we identified a novel virus in apple, apple necrotic mosaic virus (ApNMV), which is phylogenetically related to PNRSV and probably associated with apple mosaic disease in China. Full-length cDNA clones of PNRSV and ApNMV were constructed, and both are infectious in cucumber (Cucumis sativus L.), an experimental host. PNRSV exhibited higher systemic infection efficiency with more severe symptoms than ApNMV. Reassortment analysis of genomic RNA segments 1-3 found that RNA3 of PNRSV could enhance the long-distance movement of an ApNMV chimaera in cucumber, indicating the association of RNA3 of PNRSV with viral long-distance movement. Deletion mutagenesis of the PNRSV CP showed that the basic motif from amino acids 38 to 47 was crucial for the CP to maintain the systemic movement of PNRSV. Moreover, we found that arginine residues 41, 43 and 47 codetermine viral long-distance movement. The findings demonstrate that the CP of PNRSV is required for long-distance movement in cucumber, which expands the functions of ilarvirus CPs in systemic infection. For the first time, we identified involvement of Ilarvirus CP protein during long-distance movement.


Assuntos
Ilarvirus , Prunus , Ilarvirus/genética , Ilarvirus/metabolismo , RNA Viral/metabolismo , Prunus/genética , China
7.
J Med Virol ; 95(2): e28480, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36609919

RESUMO

The intra- and intertumoral heterogeneity of epithelial cells in human papillomavirus (HPV+ ) cervical adenocarcinoma (CEAD) remains largely unknown. To investigate this issue, we performed single-cell RNA sequencing on 19 229 epithelial cells sorted from three tumor samples of three patients with HPV+ CEAD. Six epithelial subclusters (Epi1-Epi6) were identified that showed distinct gene expression. Among these, Epi1 and Epi4 had apparent tumor hallmarks and metabolic activities. Epi1 was highly enriched in hallmarks of hypoxia, IL2/STAT5 signaling, retinol metabolism, glycolysis, and arachidonic acid metabolism, while Epi4 was highly enriched in hallmarks of G2M checkpoint, E2F targets, DNA repair, PI3K/AKT/MTOR signaling, glycolysis, fatty acid degradation, TCA cycle, and glutathione metabolism. We also investigated intertumoral epithelial heterogeneity and found that Patient 1 was highly enriched for KRAS signaling and angiogenesis, while Patient 2 was highly enriched for epithelial-mesenchymal transition and TGF-ß signaling, and Patient 3 was highly enriched for hypoxia, DNA repair, G2M checkpoint, and E2F targets. Using single-cell RNA sequencing, we revealed the intra- and intertumoral heterogeneity of epithelial cells in HPV+ CEAD, providing insights into the importance of personalized treatment for patients with HPV+ CEAD.


Assuntos
Adenocarcinoma , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Infecções por Papillomavirus/genética , Fosfatidilinositol 3-Quinases/metabolismo , Transcriptoma , Papillomavirus Humano , Hipóxia
8.
J Exp Bot ; 74(14): 4189-4207, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37086216

RESUMO

Apple necrotic mosaic virus (ApNMV) is associated with apple mosaic disease in China. However, the mechanisms of ApNMV infection, as well as host defence against the virus, are still poorly understood. Mitochondrial ATP synthase plays a fundamental role in the regulation of plant growth and development. However, mitochondrial ATP synthase function in response to virus infection remains to be defined. In the present study, a yeast two-hybrid (Y2H) screening revealed that the apple mitochondrial ATP synthase oligomycin sensitivity-conferring protein (OSCP) subunit (MdATPO) interacts with ApNMV coat protein (CP). It was further verified that overexpression of MdATPO in Nicotiana benthamiana inhibited viral accumulation. In contrast, silencing of NbATPO facilitated viral accumulation, indicating that ATPO plays a defensive role during ApNMV infection. Further investigation demonstrated that ApNMV infection accelerated abscisic acid (ABA) accumulation, and ABA negatively regulated ATPO transcription, which was related to the ability of ABA insensitive 5 (ABI5) to bind to the ABA-responsive elements (ABREs) of the ATPO promoter. Taken together, our results indicated that transcription factor ABI5 negatively regulated ATPO transcription by directly binding to its promoter, leading to the susceptibility of apple and N. benthamiana to ApNMV infection. The current study facilitates a comprehensive understanding of the intricate responses of the host to ApNMV infection.


Assuntos
Proteínas de Arabidopsis , ATPases Mitocondriais Próton-Translocadoras , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Regulação para Baixo , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Arabidopsis/metabolismo
9.
Ecol Appl ; 33(5): e2858, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084186

RESUMO

Emissions of methane (CH4 ) and nitrous oxide (N2 O) from soils to the atmosphere can offset the benefits of carbon sequestration for climate change mitigation. While past study has suggested that both CH4 and N2 O emissions from tidal freshwater forested wetlands (TFFW) are generally low, the impacts of coastal droughts and drought-induced saltwater intrusion on CH4 and N2 O emissions remain unclear. In this study, a process-driven biogeochemistry model, Tidal Freshwater Wetland DeNitrification-DeComposition (TFW-DNDC), was applied to examine the responses of CH4 and N2 O emissions to episodic drought-induced saltwater intrusion in TFFW along the Waccamaw River and Savannah River, USA. These sites encompass landscape gradients of both surface and porewater salinity as influenced by Atlantic Ocean tides superimposed on periodic droughts. Surprisingly, CH4 and N2 O emission responsiveness to coastal droughts and drought-induced saltwater intrusion varied greatly between river systems and among local geomorphologic settings. This reflected the complexity of wetland CH4 and N2 O emissions and suggests that simple linkages to salinity may not always be relevant, as non-linear relationships dominated our simulations. Along the Savannah River, N2 O emissions in the moderate-oligohaline tidal forest site tended to increase dramatically under the drought condition, while CH4 emission decreased. For the Waccamaw River, emissions of both CH4 and N2 O in the moderate-oligohaline tidal forest site tended to decrease under the drought condition, but the capacity of the moderate-oligohaline tidal forest to serve as a carbon sink was substantially reduced due to significant declines in net primary productivity and soil organic carbon sequestration rates as salinity killed the dominant freshwater vegetation. These changes in fluxes of CH4 and N2 O reflect crucial synergistic effects of soil salinity and water level on C and N dynamics in TFFW due to drought-induced seawater intrusion.


Assuntos
Óxido Nitroso , Áreas Alagadas , Solo/química , Metano , Carbono , Florestas , Dióxido de Carbono/análise
10.
Environ Res ; 239(Pt 1): 117286, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37797668

RESUMO

In the field of environmental science, traditional methods for predicting PM2.5 concentrations primarily focus on singular temporal or spatial dimensions. This approach presents certain limitations when it comes to deeply mining the joint influence of multiple monitoring sites and their inherent connections with meteorological factors. To address this issue, we introduce an innovative deep-learning-based multi-graph model using Beijing as the study case. This model consists of two key modules: firstly, the 'Meteorological Factor Spatio-Temporal Feature Extraction Module'. This module deeply integrates spatio-temporal features of hourly meteorological data by employing Graph Convolutional Networks (GCN) and Long Short-Term Memory (LSTM) for spatial and temporal encoding respectively. Subsequently, through an attention mechanism, it retrieves a feature tensor associated with air pollutants. Secondly, these features are amalgamated with PM2.5 concentration values, allowing the 'PM2.5 Concentration Prediction Module' to predict with enhanced accuracy the joint influence across multiple monitoring sites. Our model exhibits significant advantages over traditional methods in processing the joint impact of multiple sites and their associated meteorological factors. By providing new perspectives and tools for the in-depth understanding of urban air pollutant distribution and optimization of air quality management, this model propels us towards a more comprehensive approach in tackling air pollution issues.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aprendizado Profundo , Conceitos Meteorológicos , Material Particulado
11.
Mediators Inflamm ; 2023: 6563609, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816742

RESUMO

Osteosarcoma (OS) is a malignant tumor with an extremely poor prognosis, especially in progressive patients. Immunotherapy based on immune checkpoint inhibitors (ICIs) is considered to be a promising treatment option for OS. Due to tumor heterogeneity, only a minority of patients benefit from immunotherapy. Therefore, it is urgent to explore a model that can accurately assess the response of OS to immunotherapy. In this study, we obtained the single-cell RNA sequencing datasets of OS patients from public databases and defined 34 cell clusters by dimensional reduction and clustering analysis. PTPRC was applied to identify immune cell clusters and nonimmune cell clusters. Next, we performed clustering analysis on the immune cell clusters and obtained 25 immune cell subclusters. Immune cells were labeled with CD8A and CD8B to obtain CD8+ T cell clusters. Meanwhile, we extracted the differentially expressed genes (DEGs) of CD8+ T cell clusters and other immune cell clusters. Furthermore, we constructed a prognostic model (CD8-DEG model) based on the obtained DEGs of CD8+ T cells, and verified the excellent predictive ability of this model for the prognosis of OS. Moreover, we further investigated the value of the CD8-DEG model. The results indicated that the risk score of the CD8-DEG model was an independent risk factor for OS patients. Finally, we revealed that the risk score of the CD8-DEG model correlates with the immune profile of OS and can be used to evaluate the response of OS to immunotherapy. In conclusion, our study revealed the critical role of CD8 cells in OS. The risk score model based on CD8-DEGs can provide guidance for prognosis and immunotherapy of OS.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Linfócitos T CD8-Positivos , Prognóstico , Imunoterapia
12.
J Asian Nat Prod Res ; 25(11): 1038-1043, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37071690

RESUMO

One new sesquiterpene, (6S,7R,11S)-13-carboxy-1(10)-en-dihydroartemisinic acid (1), together with three known sesquiterpenes, ainsliaea acid B (2), mongolicumin B (3), and 11ß,13-dihydroxydeacetylmatricarin (4) were isolated from Taraxacum mongolicum Hand.-Mazz. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy, ECD spectroscopy, and X-ray diffraction analysis. Compound 1 was found to have potential anti-inflammatory activity and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rate of 37%.


Assuntos
Asteraceae , Sesquiterpenos , Taraxacum , Animais , Camundongos , Taraxacum/química , Espectroscopia de Ressonância Magnética , Macrófagos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Estrutura Molecular
13.
Ecol Appl ; 32(8): e2700, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35751513

RESUMO

Tidal freshwater forested wetlands (TFFW) provide critical ecosystem services including an essential habitat for a variety of wildlife species and significant carbon sinks for atmospheric carbon dioxide. However, large uncertainties remain concerning the impacts of climate change on the magnitude and variability of carbon fluxes and storage across a range of TFFW. In this study, we developed a process-driven Tidal Freshwater Wetlands DeNitrification-DeComposition model (TFW-DNDC) that has integrated new features, such as soil salinity effects on plant productivity and soil organic matter decomposition to explore carbon dynamics in the TFFW in response to drought-induced saltwater intrusion. Eight sites along the floodplains of the Waccamaw River (USA) and the Savannah River (USA) were selected to represent the TFFW transition from healthy to moderately and highly salt-impacted forests, and eventually to oligohaline marshes. The TFW-DNDC was calibrated and validated using field observed annual litterfall, stem growth, root growth, soil heterotrophic respiration, and soil organic carbon storage. Analyses indicate that plant productivity and soil carbon sequestration in TFFW could change substantially in response to increased soil pore water salinity and reduced soil water table due to drought, but in interactive ways dependent on the river simulated. These responses are variable due to nonlinear relationships between carbon cycling processes and environmental drivers. Plant productivity, plant respiration, soil organic carbon sequestration rate, and storage in the highly salt-impacted forest sites decreased significantly under drought conditions compared with normal conditions. Considering the high likelihood of healthy and moderately salt-impacted forests becoming highly salt-impacted forests under future climate change and sea-level rise, it is very likely that the TFFW will lose their capacity as carbon sinks without up-slope migration.


Assuntos
Salinidade , Áreas Alagadas , Ecossistema , Secas , Solo , Carbono , Florestas , Água Doce
14.
Inorg Chem ; 61(16): 6110-6119, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35416038

RESUMO

Designing ligands with efficient actinide (An(III))/lanthanide (Ln(III)) separation performance is still one of the key issues for the disposal of accumulated radioactive waste and the recovery of minor actinides. Recently, the hydrophilic ligands as promising extractants in the innovative Selective ActiNide Extraction (i-SANEX) process show excellent selectivity for Am(III) over Eu(III), such as hydroxylated-based ligands. In this work, we investigated the selective back-extraction toward Am(III) over Eu(III) with three hydrophilic hydroxylated triazolyl-based ligands (the skeleton of pyridine La, bipyridine Lb, and phenanthroline Lc) using scalar-relativistic density functional theory. The properties of three hydrophilic hydroxylated ligands and the coordination structures, bonding nature, and thermodynamic properties of the Am(III) and Eu(III) complexes with three ligands have been evaluated using multiple theoretical methods. The results of molecular orbitals (MOs), quantum theory of atoms in molecules (QTAIMs), and natural bond orbital (NBO) reveal that Am-N bonds possess more covalent character compared to Eu-N bonds. The thermodynamic results indicate that the complexing ability of Lb and Lc with metal ions is almost the same, which is stronger than that of La. However, La has the best Am(III)/Eu(III) selectivity among three ligands, which is attributed to the largest difference in covalency between Am-Ntrzl and Eu-Ntrzl bonds in MLa(NO3)3. This work provides an in-depth understanding of the preferential selectivity of the hydrophilic hydroxylated ligands with An(III) over Ln(III) and also provides theoretical support for designing potential hydrophilic ligands with excellent separation performance of Am(III)/Eu(III).

15.
J Appl Clin Med Phys ; 23(2): e13488, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34897951

RESUMO

BACKGROUND: The maximum slope (MS) and deconvolution (DC) algorithms are commonly used to post-process computed tomography perfusion (CTP) data. This study aims to analyze the differences between MS and DC algorithms for the calculation of pancreatic CTP parameters. METHODS: The pancreatic CTP data of 57 patients were analyzed using MS and DC algorithms. Two blinded radiologists calculated pancreatic blood volume (BV) and blood flow (BF). Interobserver correlation coefficients were used to evaluate the consistency between two radiologists. Paired t-tests, Pearson linear correlation analysis, and Bland-Altman analysis were performed to evaluate the correlation and consistency of the CTP parameters between the two algorithms. RESULTS: Among the 30 subjects with normal pancreas, the BV values in the three pancreatic regions were higher in the case of the MS algorithm than in the case of the DC algorithm (t = 39.35, p < 0.001), and the BF values in the three pancreatic regions were slightly higher for the MS algorithm than for the DC algorithm (t = 2.19, p = 0.031). Similarly, among the 27 patients with acute pancreatitis, the BV values obtained using the MS methods were higher than those obtained using the DC methods (t = 54.14, p < 0.001). Furthermore, the BF values were higher with the MS methods than the DC methods (t = 8.45, p < 0.001). Besides, Pearson linear correlation and Bland-Altman analysis showed that the BF and BV values showed a good correlation and a bad consistency between the two algorithms. CONCLUSIONS: The BF and BV values measured using MS and DC algorithms had a good correlation but were not consistent.


Assuntos
Pancreatite , Doença Aguda , Algoritmos , Humanos , Pâncreas/diagnóstico por imagem , Perfusão , Tomografia Computadorizada por Raios X
16.
Sensors (Basel) ; 22(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36146333

RESUMO

Developing a fluorescent probe for UO22+, which is resistant to interference from other ions such as Cu2+ and can be applied in acidic and high-water systems, has been a major challenge. In this study, a "turn-off" fluorescent probe for triamine-modified flavonoid derivatives, 2-triphenylamine-3-hydroxy-4H-chromen-4-one (abbreviated to HTPAF), was synthesized. In the solvent system of dimethyl sulfoxide:H2O (abbreviated to DMSO:H2O) (v/v = 5:95 pH = 4.5), the HTPAF solution was excited with 364 nm light and showed a strong fluorescence emission peak at 474 nm with a Stokes shift of 110 nm. After the addition of UO22+, the fluorescence at 474 nm was quenched. More importantly, there was no interference in the presence of metal ions (Pb2+, Cd2+, Cr3+, Fe3+, Co2+, Th4+, La3+, etc.), especially Cu2+ and Al3+. It is worth noting that the theoretical model for the binding of UO22+ to HTPAF was derived by more detailed density functional theory (DFT) calculations in this study, while the coordination mode was further verified using HRMS, FT-IR and 1HNMR, demonstrating a coordination ratio of 1:2. In addition, the corresponding photo-induced electron transfer (PET) fluorescence quenching mechanism was also proposed.


Assuntos
Corantes Fluorescentes , Água , Aminas/química , Cádmio , Dimetil Sulfóxido , Flavonoides , Corantes Fluorescentes/química , Íons , Chumbo , Solventes , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
17.
J Asian Nat Prod Res ; 24(5): 490-495, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35068288

RESUMO

Two new sesquiterpene dimers, lappadimers A and B, were isolated from the roots of Saussurea lappa (Yunmuxiang). Their structures were established on the basis of spectroscopic methods. They were found to have potential anti-inflammatory activity at 10 µM and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rates of 67% and 47%, respectively.


Assuntos
Saussurea , Sesquiterpenos , Animais , Macrófagos , Camundongos , Estrutura Molecular , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Saussurea/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia
18.
Int J Mol Sci ; 23(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35682808

RESUMO

The initiation and quality of flowering directly affect the time to market and economic benefit of cultivated strawberries, but the underlying mechanisms of these processes are largely unknown. To investigate the gene activity during the key period of floral induction in strawberries, time-course transcriptome analysis was performed on the shoot apex of the strawberry cultivar 'Benihoppe.' A total of 7177 differentially expressed genes (DEGs) were identified through pairwise comparisons. These DEGs were grouped into four clusters with dynamic expression patterns. By analyzing the key genes in the potential flowering pathways and the development of the leaf and flower, at least 73 DEGs that may be involved in the regulatory network of floral induction in strawberries were identified, some of which belong to the NAC, MYB, MADS, and SEB families. A variety of eight hormone signaling pathway genes that might play important roles in floral induction were analyzed. In particular, the gene encoding DELLA, a key inhibitor of the gibberellin signaling pathway, was found to be significantly differentially expressed during the floral induction. Furthermore, the differential expression of some important candidate genes, such as TFL1, SOC1, and GAI-like, was further verified by qRT-PCR. Therefore, we used this time-course transcriptome data for a preliminary exploration of the regulatory network of floral induction and to provide potential candidate genes for future studies of flowering in strawberries.


Assuntos
Fragaria , Flores/metabolismo , Fragaria/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Humanos , Transcriptoma
19.
Inorg Chem ; 60(21): 16409-16419, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34632757

RESUMO

In this work, we focused on the separation of Am(III)/Eu(III) with four hydrophilic sulfonated ligands (L) based on the framework of phenanthroline and bipyridine through scalar relativistic density functional theory. We studied the electronic structures of [ML(NO3)3] (M = Am, Eu) complexes and the bonding nature between metal and ligands as well as evaluated the separation selectivity of Am(III)/Eu(III). The tetrasulfonated ligand L2 with a bipyridine framework has the strongest complexing ability for metal ions probably because of the better solubility and flexible skeleton. The disulfonated ligand L1 has the highest Am(III)/Eu(III) selectivity, which is attributed to the covalent difference between the Am-N and Eu-N bonds based on the quantum theory of atoms in the molecule analysis. Thermodynamic analysis shows that the four hydrophilic sulfonated ligands are more selective toward Am(III) over Eu(III). In addition, these hydrophilic sulfonated ligands show better complexing ability and Am(III)/Eu(III) selectivity compared to the corresponding hydrophobic nonsulfonated ones. This work provides theoretical support for the separation of Am(III)/Eu(III) using hydrophilic sulfonated ligands.

20.
Arch Virol ; 166(7): 2059-2062, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33983504

RESUMO

China rose (Rosa chinensis Jacq.) is an important ornamental plant grown widely in China. In May 2019, we sampled and analyzed a China rose plant by high-throughput sequencing using small RNAs. A luteovirus, rose spring dwarf-associated virus (RSDaV), was detected in this plant, and its complete nucleotide sequence of 5816 nucleotides was determined. The China rose isolate of RSDaV contains five major open reading frames (ORFs) and three putative small ORFs, typical of members of the genus Luteovirus. It shares 94.4% nt sequence identity with the Californian (USA) isolate of the virus. Genomic analysis revealed a deletion of a single U at nt position 5295, which introduced a frameshift mutation, and an insertion of nine nucleotides (AUAAAUGAU) at position 5706-5714, which did not change the reading frame. The aa sequence in that portion of the protein was 90.5% identical to that of the Californian isolate. This is the first report on the occurrence of RSDaV infecting rose plants in China.


Assuntos
Genoma Viral/genética , Luteovirus/genética , Doenças das Plantas/virologia , Rosa/virologia , Sequência de Bases , China , Mutação da Fase de Leitura/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Fases de Leitura Aberta/genética , Filogenia , RNA Viral/genética
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