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1.
Food Chem ; 462: 141002, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-39216371

RESUMO

Making health-enhancing tea from Forsythia suspensa leaves has been a tradition of Chinese folk culture for centuries. However, these leaves were not officially recognized as a new food source until 2017 by the Chinese government. In this study, ethyl acetate fractions from Forsythia suspensa fruit and leaves exhibited excellent antioxidant activity in vitro antioxidant assays and in vivo D-galactose-induced aging mice model. The antioxidant activity of the leaves was higher than that of fruit both in vitro and in vivo. The chemical constituents present in these ethyl acetate fractions were comprehensively analyzed using UHPLC-Q-Exactive-Orbitrap/MS. A total of 20 compounds were identified, among which forsythoside E, (+)-epipinoresinol, dihydromyricetin, chlorogenic acid, and ursolic acid were exclusively detected in the ethyl acetate fraction of Forsythia suspensa leaves, but absent in the ethyl acetate fraction derived from its fruit. This study provides theoretical support for the utilization of Forsythia suspensa fruit and leaves.


Assuntos
Envelhecimento , Antioxidantes , Forsythia , Frutas , Galactose , Extratos Vegetais , Folhas de Planta , Animais , Forsythia/química , Folhas de Planta/química , Camundongos , Frutas/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Antioxidantes/química , Antioxidantes/farmacologia , Envelhecimento/efeitos dos fármacos , Masculino , Humanos , Espectrometria de Massas
2.
Front Pharmacol ; 15: 1430469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39380912

RESUMO

Cisplatin is widely used to treat various solid tumors. However, its toxicity to normal tissues limits its clinical application, particularly due to its ototoxic effects, which can result in hearing loss in patients undergoing chemotherapy. While significant progress has been made in preclinical studies to elucidate the cellular and molecular mechanisms underlying cisplatin-induced ototoxicity (CIO), the precise mechanisms remain unclear. Moreover, the optimal protective agent for preventing or mitigating cisplatin-induced ototoxicity has yet to be identified. This review summarizes the current understanding of the roles of apoptosis, autophagy, ferroptosis, pyroptosis, and protective agents in cisplatin-induced ototoxicity. A deeper understanding of these cell death mechanisms in the inner ear, along with the protective agents, could facilitate the translation of these agents into clinical therapeutics, help identify new therapeutic targets, and provide novel strategies for cisplatin-based cancer treatment.

3.
Phys Rev Lett ; 133(14): 140201, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39423375

RESUMO

The manipulation and transformation of quantum resources are key parts of quantum mechanics. Among them, asymmetry is one of the most useful operational resources, which is widely used in quantum clocks, quantum metrology, and other tasks. Recent studies have shown that the asymmetry of quantum states can be significantly amplified with the assistance of correlating catalysts that are finite-dimensional auxiliaries. In the experiment, we perform translationally invariant operations, ensuring that the asymmetric resources of the entire system remain nonincreasing, on a composite system composed of a catalytic system and a quantum system. The experimental results demonstrate an asymmetry amplification of 0.0172±0.0022 in the system following the catalytic process. Our Letter showcases the potential of quantum catalytic processes and is expected to inspire further research in the field of quantum resource theories.

4.
J Nutr ; 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39424066

RESUMO

Poultry, a vital economic animal, provide a high quality protein source for human nutrition. Over the past decade, the poultry industry has witnessed substantial achievements in breeding, precision feeding, and welfare farming. However, there are still many challenges restricting the sustainable development of the poultry industry. Firstly, overly focused breeding strategies on production performance have been shown to induce metabolic diseases in poultry. Secondly, a lack of robust methods for assessing the nutritional requirements poses a challenge to the practical implementation of precision feeding. Thirdly, antibiotic alternatives and feed safety management remain pressing concerns within the poultry industry. Lastly, environmental pollution and inadequate welfare management in farming have a negative effect on poultry health. Despite numerous proposed strategies and innovative approaches, each faces its own set of strengths and limitations. In this review, we aim to provide a comprehensive understanding of the poultry industry over the past decade, by examining its achievements, challenges, and strategies, in order to guide its future direction.

5.
Org Lett ; 26(42): 9097-9102, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39413030

RESUMO

Gem-borylsilylalkanes are versatile intermediates in organic synthesis, and the traditional synthesis methods have mainly focused on metal reagents, the insertion reactions of diazo compounds, and hydrosilylation/hydroborylation reactions of unsaturated bonds. Herein, a novel, efficient gem-borylsilylalkanes synthesis via a radical approach is reported. This method introduced a ß-gem-borylsilyl NHPI ester as the precursor of the ß-borylsilyl radical that, coupling with radical acceptors under photo conditions, and the corresponding gem-borylsilylalkanes bearing unsaturated bonds, facilitate subsequent transformations.

6.
Complement Ther Med ; 86: 103098, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39395482

RESUMO

OBJECTIVE: To rigorously evaluate the short-term and long-term effectiveness of Tuina (TN), alone and in combination with physiotherapy (PT), for Chronic nonspecific low back pain (CNLBP) through a comprehensive, high-quality clinical trial. METHODS: This randomized, single-blind trial was conducted from September 2020 to July 2023, involving 204 CNLBP patients from the First Affiliated Hospital of Jinan University. Participants underwent a baseline assessment, 6 treatment sessions over 8 weeks, a post-treatment evaluation in the 9th week, and a 20-week follow-up. Participants were randomly assigned to TN, PT, or a combination of TN and PT (TP) groups. Each treatment involved 6 sessions with a minimum 7-day interval, each lasting 30 minutes. Primary outcome was the change in Visual Analog Scale (VAS) for pain. Secondary outcomes included the Oswestry Disability Index (ODI), 36-Item Short Form Health Survey (SF-36), Range of Motion (ROM) of the spine, Traditional Chinese Medicine Syndrome Scale (TCMSS), and adverse events (AE). RESULTS: Among the 204 participants, 67.16 % were female, and 88.73 % completed the 20-week follow-up. All groups showed significant reductions in VAS scores post-treatment and at follow-up. Secondary outcomes improved significantly, with notable decreases in ODI and TCMSS scores. Pairwise comparisons within groups indicated statistical significance, particularly in ODI scores, with clinical relevance. No significant differences were found between the groups. ROM and SF-36 showed statistical but not clinical significance. Only one AE (0.49 %) was reported, with no severe incidents. CONCLUSION: All treatment groups, including TN, TP, and PT, demonstrated significant reductions in VAS scores for CNLBP patients, with effects lasting up to 20 weeks. While TN and TP showed substantial improvements in secondary outcomes, particularly in ODI scores, no significant differences were found between the groups. These findings suggest that all treatments can be effective for managing CNLBP, supporting clinical practitioners in selecting appropriate interventions for patients, especially for those unable to engage in active exercises, utilizing passive movements like TN to enhance health outcomes.


Assuntos
Dor Lombar , Modalidades de Fisioterapia , Humanos , Dor Lombar/terapia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Método Simples-Cego , Medição da Dor , Dor Crônica/terapia , Terapia Combinada , Resultado do Tratamento
7.
Sci Rep ; 14(1): 24361, 2024 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420122

RESUMO

Prior research show that relative deprivation can decrease individuals' psychological well-being. However, the underlying mechanism between relative deprivation and psychological well-being remains unclear. To explore the mediating effects of self-efficacy and self-control on the relationship between relative deprivation and psychological well-being. 426 undergraduate students submitted the online survey that assessed their psychological well-being, relative deprivation, self-efficacy and self-control. Students experienced high levels of psychological well-being, moderate to high levels of relative deprivation and moderate levels of self-efficacy and self-control. Parallel mediators of self-efficacy and self-control on the relationship between relative deprivation and psychological well-being were significant (each p < 0.01). This study explores the underlying mechanism between relative deprivation and psychological well-being by identifying the parallel mediators of self-efficacy and self-control. Effective interventions should be taken to alleviate students' relative deprivation and promote their self-efficacy, self-control and psychological well-being during future pandemics.


Assuntos
COVID-19 , Autoeficácia , Autocontrole , Estudantes , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Masculino , Feminino , Estudantes/psicologia , Adulto Jovem , Autocontrole/psicologia , Inquéritos e Questionários , Saúde Mental , Adulto , Pandemias , SARS-CoV-2 , Universidades , Adolescente , Bem-Estar Psicológico
8.
Nat Commun ; 15(1): 8601, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39366932

RESUMO

Over the past decade, there has been a growing interest in ferritin-based vaccines due to their enhanced antigen immunogenicity and favorable safety profiles, with several vaccine candidates targeting various pathogens advancing to phase I clinical trials. Nevertheless, challenges associated with particle heterogeneity, improper assembly and unanticipated immunogenicity due to the bulky protein adaptor have impeded further advancement. To overcome these challenges, we devise a universal ferritin-adaptor delivery platform based on structural insights derived from the natural ferritinophagy complex of the human ferritin heavy chain (FTH1) and the nuclear receptor coactivator 4 (NCOA4). The engineered ferritinophagy (Fagy)-tag peptide demonstrate significantly enhanced binding affinity to the 24-mer ferritin nanoparticle, enabling efficient antigen presentation. Subsequently, we construct a self-assembling rabies virus (RABV) vaccine candidate by noncovalently conjugating the Fagy-tagged glycoprotein domain III (GDIII) of RABV to the ferritin nanoparticle, maintaining superior homogeneity, stability and immunogenicity. This vaccine candidate induces potent, rapid, and durable immune responses, and protects female mice against the authentic RABV challenge after single-dose administration. Furthermore, this universal, ferritin-based antigen conjugating strategy offers significant potential for developing vaccine against diverse pathogens and diseases.


Assuntos
Apoferritinas , Ferritinas , Nanopartículas , Vacina Antirrábica , Vírus da Raiva , Raiva , Animais , Nanopartículas/química , Vírus da Raiva/imunologia , Vírus da Raiva/genética , Camundongos , Humanos , Feminino , Raiva/prevenção & controle , Raiva/imunologia , Apoferritinas/química , Apoferritinas/imunologia , Apoferritinas/genética , Vacina Antirrábica/imunologia , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/genética , Vacina Antirrábica/química , Ferritinas/imunologia , Ferritinas/química , Ferritinas/metabolismo , Anticorpos Antivirais/imunologia , Camundongos Endogâmicos BALB C , Antígenos Virais/imunologia , Antígenos Virais/química , Antígenos Virais/genética , Oxirredutases
9.
Int J Biol Macromol ; 281(Pt 3): 135871, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39357718

RESUMO

Histone modifications (HMs) play various roles in growth, development, and resistance to abiotic stress. However, HMs have been systematically identified in a few plants, and identification of HMs in medicinal plants is very rare. Aquilaria sinensis is a typical stress-induced medicinal plant, in which HMs remain unexplored. We conducted a comprehensive study to identify HMs and obtained 123 HMs. To conduct evolutionary analysis, we constructed phylogenetic trees and analyzed gene structures. To conduct functional analysis, we performed promoter, GO, and KEGG analyses and ortholog analyses against AtHMs. Based on the expression profiles of different tissues and different layers of Agar-Wit, some HMs of A. sinensis (AsHMs) were predicted to be involved in the formation of agarwood, and their response to MeJA and NaCl stress was tested by qRT-PCR analysis. By analyzing the enrichment of H3K4me3, H3K27me3, and H4K5ac in the promoter regions of two key sesquiterpene synthase genes, AsTPS13/18, we hypothesized that AsHMs play important roles in the synthesis of agarwood sesquiterpenes. We confirmed this hypothesis by conducting RNAi transgenic interference experiments. This study provided valuable information and important biological theories for studying epigenetic regulation in the formation of agarwood. It also provided a framework for conducting further studies on the biological functions of HMs.

10.
Sci Total Environ ; 954: 176825, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389128

RESUMO

Microbial necromass carbon (MNC) is a major source of soil organic carbon (SOC) pool, significantly influencing soil carbon sequestration. The effects of long-term water and nitrogen addition on MNC in soils at different depths, as well as their interactions, remain poorly understood. In this study, we examined the influence of water addition (+51.67 mm), nitrogen addition (25, 50, 100 kg N ha-1 yr-1), and their interactions on MNC accumulation at different soil depths in temperate grasslands. The addition of water and nitrogen over nine years has been observed to exhibit a decreasing trend in the MNC at different soil depths. Notably, MNC in the topsoil layer (0-10 cm) decreased significantly by 18.56 % under low nitrogen addition treatment, while MNC in the subsoil layer (40-60 cm) declined significantly by 27.19 % under high nitrogen addition treatment. Fungal microbial necromass carbon (FNC) contributed 3.25 times more to SOC than bacterial microbial necromass carbon (BNC). In the 0-10 cm soil layer, MNC is primarily governed by both microbial attributes and the physicochemical properties of the soil, in the 20-40 cm soil layer, the physicochemical properties of the soil predominantly control MNC, in the 40-60 cm layer, microbial characteristics exert a more significant influence on MNC. Collectively, our observations suggest that soil MNC decreased with the addition of water and nitrogen in the 0-60 cm soil slope, which could enable the accurate prediction of global change impacts on the accumulation of soil carbon, thus facilitating the implementation of strategies to augment soil carbon sequestration.

11.
Plant Sci ; 350: 112277, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389317

RESUMO

R2R3-MYB transcription factors function as the master regulators of the phenylpropanoid pathway in which both lignin and anthocyanin are produced. In poplar, R2R3-MYB transcription factor PdMYB118 positively regulates anthocyanin production to change leaf color. However, the molecular mechanism by which it controls different branches of the phenylpropanoid pathway still remains poorly understood. Here, we reported that in addition to anthocyanin synthesis, lignin deposition and xylem differentiation were regulated by PdMYB118 through inhibiting PagKNAT2/6b gene expression. The transgenic poplar plants overexpressing PdMYB118 accumulated more xylem, lignin and anthocyanin. Transcriptome and reverse transcription quantitative PCR analyses revealed that the expression of PagKNAT2/6b gene which inhibited lignin deposition and xylem differentiation was significantly down-regulated in transgenic poplar plants. Subsequent dual-luciferase reporter and yeast-one-hybrid assays demonstrated that PdMYB118 directly inhibited the transcription of PagKNAT2/6b by binding to the AC elements in its promoter region. Further experiments with transgenic poplar plants overexpressing PagKNAT2/6b demonstrated that overexpression of PagKNAT2/6b in the PdMYB118 overexpression background rescued lignin accumulation and xylem width to the same level of wild type plants. The findings in this work suggest that PdMYB118 is involved in the lignin deposition and xylem differentiation via modulating the expression of PagKNAT2/6b, and the PdMYB118- PagKNAT2/6b model can be used for the genetic breeding of new woody tree with high lignin production.

12.
BMC Anesthesiol ; 24(1): 364, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390365

RESUMO

BACKGROUND: In addition to their classic genomic effects, glucocorticoids also manifest rapid non genomic effects. We speculate that dexamethasone has the potential prompt onset of analgesic effects. The objective of this study is to investigate the influence of a single preoperative dose of dexamethasone on the half maximal effective concentration (EC50) of remifentanil when combined with dexmedetomidine for pain relief during pancreatic extracorporeal shockwave lithotripsy (P-ESWL). METHODS: A total of 60 patients undergoing P-ESWL were enrolled and randomized at 1:1 ratio into the dexamethasone (DXM) group and the placebo group. Before anesthesia induction, patients in DXM group received an intravenous injection of 8 mg dexamethasone, while subjects in placebo group received an equal dose of physiological saline. Monitored anesthesia care (MAC) was performed based on remifentanil in combination with dexmedetomidine. Remifentanil was administered by TCI with an initial target concentration of 2.5 µg/mL for both groups. A positive response was defined as that VAS score > 3 by the patient at any time during the procedure. Subsequent target concentrations were adjusted by Dixon up-down sequential method, where dose modifications were performed by 0.3 ng/mL intervals, based on the response of the previous patient. The EC50 of remifentanil for pain relief during P-ESWL treatment was calculated using Dixon's up-and-down method. Hemodynamic variables, oxygen saturation and adverse events were also recorded. RESULTS: Dixon up-and-down method revealed that the EC50 of remifentanil was significantly higher in placebo group (2.65 ± 0.28 ng/mL) than in DXM group (2.02 ± 0.23 ng/ml) (P < 0.001). Hemodynamic parameter exhibited a significant decrease in mean arterial pressure (MAP) and heart rate (HR) before and after induction in placebo group; however, data of the two groups were comparable (P>0.05). Less adverse events occurred in DXM group, including the incidence of postoperative nausea and vomiting (PONV) and analgesia requirement with in the first 24 h following the procedure at ward. CONCLUSION: Dexamethasone exerted analgesic effects with a rapid onset, and patients received dexamethasone 8 mg preoperative had a lower required EC50 of remifentanil during P-ESWL. It is also associated with reduced PONV in addition to reduced postoperative analgesic consumption in the first postoperative 24 h. TRIAL REGISTRATION: Registered in the Chinese Clinical Trial Registry (ChiCTR2300078171) on 30/11/2023.


Assuntos
Dexametasona , Dexmedetomidina , Quimioterapia Combinada , Litotripsia , Remifentanil , Humanos , Remifentanil/administração & dosagem , Dexmedetomidina/administração & dosagem , Dexmedetomidina/farmacologia , Dexametasona/administração & dosagem , Feminino , Masculino , Estudos Prospectivos , Litotripsia/métodos , Pessoa de Meia-Idade , Adulto , Método Duplo-Cego , Analgésicos Opioides/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Relação Dose-Resposta a Droga
13.
Mol Pharm ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39351992

RESUMO

Intracellular copper ion homeostasis has become an attractive target for cancer therapy. Herein, we report a 2,2'-dipicolylamine (DPA) functionalized polyglutamate derivative (PDHB) which is capable of rapidly forming PDHB-copper complex (PDHB@Cu) due to the strong coordination ability of pendant DPA with Cu2+. High drug loading content of doxorubicin (DOX) (>30 wt %) is realized due to the strong affinity of Cu2+ to DOX, while that is about 10 wt % for PDHB without Cu2+. The obtained PDHB@Cu-DOX can respond to specific endogenous stimuli (pH and glutathione (GSH)), releasing Cu2+ and DOX. The released DOX directly damages the DNA of tumor cells to cause apoptosis, while Cu2+ depletes intracellular GSH and is reduced to Cu+ simultaneously, which reacts with local H2O2 to produce highly toxic ·OH via a Fenton-like reaction, thus realizing synergistic chemodynamics and chemotherapy. This report provides an interesting polymeric ionophore strategy to deliver enough copper ions into cancer cells, which can also easily extend to other metal ions by replacing the ionophore components, thus having a wide application in nanomedicine.

14.
Nano Lett ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352718

RESUMO

The design and synthesis of nanomedicines capable of regulating programmed cell death patterns to enhance antitumor efficacy remain significant challenges in cancer therapy. In this study, we developed intelligent DNA nanospheres (NS) capable of distinguishing tiny pH changes between different endosomal compartments to regulate pyroptosis or apoptosis. These NS are self-assembled from two multifunctional DNA modules, enabling tumor targeting, acid-responsive disassembly, and photodynamic therapy (PDT) activation. By modifying the embedded i-motif sequence, the NS can be activated in early endosomes (EE) or lysosomes (Ly), producing singlet oxygen (1O2) at specific locations under laser irradiation. Our results demonstrate that EE-activated PDT induces gasdermin-E-mediated pyroptosis in tumor cells, enhancing antitumor efficacy and reducing systemic toxicity compared to Ly-activated apoptosis. This study offers new insights into the design of endosome-activated nanomedicines, advancing the biomedical applications of targeted cancer therapy.

15.
Disaster Med Public Health Prep ; 18: e211, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39463311

RESUMO

OBJECTIVE: The initial emergence of SARS-CoV-2 created uncertainty for humanity, driving people to seek assistance on social media. This study aims to understand the role of social media in coping with crises and to offer guidance for future uncertainties by examining the experiences of Wuhan during the early stages of the pandemic. METHODS: Using quantitative content analysis, this study investigated 2207 Weibo posts tagged with "COVID-19 Mutual Aid" from individuals located in Wuhan during the early lockdown period from January 23, 2020, to March 23, 2020. RESULTS: At the start of pandemic, messages seeking tangible support were most common. A hurdle regression model showed that deeper self-disclosure led to more retransmission of help-seeking messages. The Chi-Square and Mann-Whitney U tests revealed that health professionals and laypeople had different self-disclosure strategies. CONCLUSIONS: This study provides insight into the online social support exchange during the early stages of the COVID-19 pandemic in Wuhan, highlighting the importance of self-disclosure on message retransmission, and the differences in self-disclosure strategies between health professionals and laypeople in online help-seeking.


Assuntos
COVID-19 , Pandemias , Mídias Sociais , Humanos , COVID-19/psicologia , COVID-19/epidemiologia , Mídias Sociais/estatística & dados numéricos , China/epidemiologia , Adaptação Psicológica , SARS-CoV-2
16.
Huan Jing Ke Xue ; 45(10): 5970-5982, 2024 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-39455141

RESUMO

The Huaihe River Basin is located in the north-south climate transition zone of China. The change of carbon storage in this area is of great significance for predicting the future ecological protection, mitigating climate change, and maintaining sustainable development of the Huaihe River Basin. The middle and upper reaches of Huaihe River Basin (above Bengbu station) were taken as the research area. Based on the land use data from 1980 to 2020, the PLUS model was used to simulate and predict the land use types in the study area from 2030 to 2100 under the scenarios of SSP1-2.6, SSP2-4.5, SSP5-8.5, and the continuation of land use status. The carbon module in the InVEST model was used to simulate and predict the carbon storage from 1980 to 2020 and the carbon storage from 2030 to 2100 under various scenarios, and the spatial and temporal changes of carbon storage in the middle and upper reaches of the Huaihe River Basin were compared and analyzed. The results showed that: ① From 1980 to 2020, the basin showed a decrease in both cultivated land and grassland,and the area of forest,water, construction, and unused land all increased, among which the area of cultivated land continued to decrease, with a total decrease of 4 699 km2 in 40 a. Construction land continued to increase, with a total increase of 4 592 km2 in 40 a. ② The carbon storage in the basin showed a downward trend, with a total reduction of 1.05×107 t from 1980 to 2020. ③ In the four scenarios, the area of each land type had different degrees of change, and that of the SSP1-2.6 scenario was relatively small out of the four scenarios. ④ Compared with the carbon storage in 2020, the carbon storage in the SSP1-2.6 scenario increased by 8.7×104 t, the carbon storage in the SSP2-4.5 scenario decreased by 1.42×107 t, the carbon storage in the SSP5-8.5 scenario decreased by 1.34×107 t, and the carbon storage in the current continuation scenario decreased by 1.22×107 t. The study can provide a scientific basis for land use structure management and ecological protection in the middle and upper reaches of the Huaihe River Basin (above Bengbu station) in the future.

17.
Nano Lett ; 24(43): 13534-13541, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39404710

RESUMO

Manipulating the symmetry of fullerene-based low-dimensional materials is crucial to the development of electronic devices and modern nonvolatile memories. However, there have been few reports on studying the physicochemical properties of fullerene and its derivatives by controlling the symmetries. Herein, we demonstrate ferroelectricity in Sc3N@Ih-C80-Pd/Pt adducts with relatively strong spontaneous polarization. Polarization originates from subtle molecular interactions between Sc3N@Ih-C80 and Pd/Pt atoms, breaking the structural symmetry. Additionally, we investigate how a temperature-dependent polar-nonpolar phase transition affects the corresponding nonadiabatic electron-hole recombination process in the ferroelectric fullerene adduct Sc3N@Ih-C80-Pd. The results indicate that polarization has a greater impact than temperature effects, resulting in an extension of the carrier lifetime in the polar phase by over 3 times compared to that in the nonpolar phase. Our findings unveil new members of the ferroelectric fullerene family and provide guidance for improving the performance of optoelectronic materials.

18.
Photochem Photobiol Sci ; 23(10): 1883-1891, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39352683

RESUMO

The disruption of lipid droplet function is associated with the pathogenesis of various diseases. Clarifying the response behavior of lipid droplets to the microenvironment at the cellular level is of great significance. Plant lipids not only exist in phospholipids in cell membranes, but also in aromatic essential oils. Monitoring the level of lipid droplets in plant cells using fluorescent probes provides a simple method for screening lipid-rich varieties. We synthesized a polarity-viscosity responsive coumarin fluorescent probe, Cou-CN, which achieved sensitive detection of polarity and viscosity in dilute solution environments by constructing this simple probe with ICT and TICT properties and verifying it using Gaussian computational simulation. Cou-CN exhibited good lipid droplet illumination effects in HepG2 cells with a correlation coefficient of 0.92 compared to the commercial lipid droplet dye BODIPY. Additionally, co-staining the probe with the lipophilic commercial dye Nile Red in tobacco root stem seedling cells resulted in a high correlation coefficient of 0.9.


Assuntos
Corantes Fluorescentes , Nicotiana , Raízes de Plantas , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Nicotiana/química , Viscosidade , Células Hep G2 , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Cumarínicos/química , Cumarínicos/síntese química , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Imagem Óptica , Estrutura Molecular
19.
Plant Sci ; 350: 112283, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39396620

RESUMO

Phloem fiber is a key component of phloem tissue and is involved in supporting its structural integrity. NAC domain transcription factors are master switches that regulate secondary cell wall (SCW) biosynthesis in xylem fibers, but the mechanism by which NACs regulate phloem fiber development remains unexplored. Here, a NAC2-like gene in poplar, PagNAC2a, was shown to be involved in phloem fiber differentiation. qRT-PCR and GUS staining revealed that PagNAC2a was specifically expressed in the phloem zone of poplar stems. The overexpression of PagNAC2a in poplar increased plant biomass by increasing plant height, stem diameter, and leaf area. Stem anatomy analysis revealed that overexpression of PagNAC2a resulted in enhanced phloem fiber differentiation and cell wall deposition. In addition, PagNAC2a directly upregulated the expression of PagATL2, a gene involved in phloem development, as revealed by yeast one hybrid (Y1H) and electrophoretic mobility shift assay (EMSA) assays. Overall, we proposed that the PagNAC2a was a positive regulator of phloem fiber development in poplar, and these results provided insights into the molecular mechanisms involved in the differentiation of phloem fibers.

20.
Precis Chem ; 2(1): 28-39, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-39474568

RESUMO

The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral materials. Facile, selective, and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship studies. Herein, we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims, enabled by the highly regioselective one-pot borylation of rationally designed precursors with, namely, fold-in or pan-out manner. The incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon helix. In addition, numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties, revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral sensors. The combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.

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