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1.
Front Med (Lausanne) ; 11: 1399511, 2024.
Article in English | MEDLINE | ID: mdl-38831989

ABSTRACT

Acrodermatitis enteropathica (AE, OMIM 201100) is a rare autosomal recessive dermatosis characterized by periorificial dermatitis, diarrhea, alopecia, and hypozincaemia due to pathogenic variants of SLC39A4. Herein, we present a case series describing four unrelated patients with AE from Han, Yi, and Tibetan ethnicities in Sichuan region of southwestern China, speculate the hotspot variants of SLC39A4 causing AE in Sichuan region and highlight physicians should be alerted to unusual presentations of AE, such as the absence of hypozincaemia and the presence of acne-like lesions. Serum alkaline phosphatase and genetic testing should be considered to accurately evaluate the zinc deficiency in human body and help make the correct diagnosis.

2.
Cancer Cell Int ; 24(1): 198, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38835077

ABSTRACT

Translationally controlled tumor protein (TCTP), also known as histamine-releasing factor (HRF) or fortilin, is a highly conserved protein found in various species. To date, multiple studies have demonstrated the crucial role of TCTP in a wide range of cellular pathophysiological processes, including cell proliferation and survival, cell cycle regulation, cell death, as well as cell migration and movement, all of which are major pathogenic mechanisms of tumorigenesis and development. This review aims to provide an in-depth analysis of the functional role of TCTP in tumor initiation and progression, with a particular focus on cell proliferation, cell death, and cell migration. It will highlight the expression and pathological implications of TCTP in various tumor types, summarizing the current prevailing therapeutic strategies that target TCTP.

3.
Article in English | MEDLINE | ID: mdl-38835647

ABSTRACT

Background: Triple-negative breast cancer (TNBC) is the most aggressive malignancy. Psychological distress and elevated CXCL1 level have been reported to be closely associated with the poor prognosis and quality of life of patients with TNBC. In preclinical studies using xenograft mouse models, XIAOPI formula, a nationally approved drug prescribed to patients at high risk for breast cancer, inhibited CXCL1 expression and improved survival. Traditional Chinese medicine has unique advantages in improving patients' emotional disorders and quality of life. However, the impact of XIAOPI formula on the serum level of CXCL1, psychological distress, and quality of life among patients with TNBC is currently unknown. Methods: In this study, we designed a randomized, double-blind, placebo-controlled trial. Patients with TNBC were randomly assigned to receive either the XIAOPI formula or a placebo for three months. The primary outcomes include serum CXCL1 expression, Self-Rating Anxiety Scale (SAS), and the Self-Rating Depression Scale (SDS). Secondary outcomes included the Pittsburgh Sleep Quality Index (PSQI) and the Functional Assessment of Cancer Therapy-Breast (FACT-B). Results: A total of 60 patients with TNBC were enrolled in the investigation. The results showed that the XIAOPI formula significantly decreased CXCL1 expression compared with the control group. Moreover, in comparison to the placebo, the XIAOPI formula increased FACT-B scores while decreasing SDS, SAS, and PSQI scores. Conclusion: In patients with TNBC, XIAOPI formula may be effective in reducing CXCL1 levels, enhancing psychological well-being, and quality of life. While our research offers a natural alternative therapy that may enhance the prognosis of TNBC, future validation of its therapeutic effects will require large-scale, long-term clinical trials. Clinical Registration Number: Registration website: www.chictr.org.cn, Registration date: 2018-1-19, Registration number: ChiCTR1800014535.

4.
Biomed Chromatogr ; : e5894, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38777624

ABSTRACT

Verbena officinalis L. as a medical plant has been used to treat many diseases. However, the quality control underlying V. officinalis remains to be studied. HPLC fingerprint analysis and the qualitative and quantitative analysis of water extract from V. officinalis were carried out, and it was found that the quality varies according to habitat and batch. Verbenalin could be a crucial component in the quality evaluation of V. officinalis. This study contributes to better understanding of quality control for V. officinalis.

5.
Cell Death Discov ; 10(1): 253, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38789436

ABSTRACT

Ferroptosis is a novel form of programmed cell death which can exacerbate lung injury in septic acute respiratory distress syndrome (ARDS). Alveolar macrophages, crucial innate immune cells, play a pivotal role in the pathogenesis of ARDS. Ferritinophagy is a process of ferritin degradation mediated by nuclear receptor coactivator 4 (NCOA4) which releases large amounts of iron ions thus promoting ferroptosis. Recent evidence revealed that inhibiting macrophage ferroptosis can effectively attenuate pulmonary inflammatory injury. Melatonin (MT), an endogenous neurohormone, has antioxidant and anti-inflammatory effects and can reduce septic ARDS. However, it is not clear whether MT's pulmonary protective effect is related to the inhibition of macrophage ferritinophagy. Our in vitro experiments demonstrated that MT decreased intracellular malondialdehyde (MDA), Fe2+, and lipid peroxidation levels, increased glutathione (GSH) levels and cell proliferation, and upregulated glutathione peroxidase 4 (GPX4) and ferritin heavy chain 1 (FTH1) protein levels in LPS-treated macrophages. Mechanistically, the antiferroptotic effect of MT on LPS-treated macrophages was significantly compromised by the overexpression of NCOA4. Our in vivo experiments revealed that MT alleviated the protein expression of NCOA4 and FTH1 in the alveolar macrophages of septic mice. Furthermore, MT improved lipid peroxidation and mitigated damage in alveolar macrophages and lung tissue, ultimately increasing the survival rates of septic mice. These findings indicate that MT can inhibit ferroptosis in an NCOA4-mediated ferritinophagy manner, thereby ameliorating septic ARDS.

6.
Article in English | MEDLINE | ID: mdl-38753528

ABSTRACT

OBJECTIVES: Detection of early neoplastic lesions is crucial for improving the survival rates of patients with gastric cancer. Optical enhancement mode 2 is a new image-enhanced endoscopic technique that offers bright images and can improve the visibility of neoplastic lesions. This study aimed to compare the detection of neoplastic lesions with optical enhancement mode 2 and white-light imaging (WLI) in a high-risk population. METHODS: In this prospective multicenter randomized controlled trial, patients were randomly assigned to optical enhancement mode 2 or WLI groups. Detection of suspicious neoplastic lesions during the examinations was recorded, and pathological diagnoses served as the gold standard. RESULTS: A total of 1211 and 1219 individuals were included in the optical enhancement mode 2 and WLI groups, respectively. The detection rate of neoplastic lesions was significantly higher in the optical enhancement mode 2 group (5.1% vs. 1.9%; risk ratio, 2.656 [95% confidence interval, 1.630-4.330]; p < 0.001). The detection rate of neoplastic lesions with an atrophic gastritis background was significantly higher in the optical enhancement mode 2 group (8.6% vs. 2.6%, p < 0.001). The optical enhancement mode 2 group also had a higher detection rate among endoscopists with different experiences. CONCLUSIONS: Optical enhancement mode 2 was more effective than WLI for detecting neoplastic lesions in the stomach, and can serve as a new method for screening early gastric cancer in clinical practice. CLINICAL REGISTRY: United States National Library of Medicine (https://www. CLINICALTRIALS: gov), ID: NCT040720521.

7.
Pharmacol Biochem Behav ; : 173773, 2024 May 26.
Article in English | MEDLINE | ID: mdl-38806116

ABSTRACT

Depression is a significant factor contributing to postoperative occurrences, and patients diagnosed with depression have a higher risk for postoperative complications. Studies on cardiovascular surgery extensively addresses this concern. Several studies report that people who undergo coronary artery bypass graft surgery have a 20% chance of developing postoperative depression. A retrospective analysis of medical records spanning 21 years, involving 817 patients, revealed that approximately 40% o individuals undergoing coronary artery bypass grafting (CABG) were at risk of perioperative depression. Patients endure prolonged suffering from illness because each attempt with standard antidepressants requires several weeks to be effective. In addition, multi-drug combination adjuvants or combination medication therapy may alleviate symptoms for some individuals, but they also increase the risk of side effects. Conventional antidepressants primarily modulate the monoamine system, whereas different therapies target the serotonin, norepinephrine, and dopamine systems. Esketamine is a fast-acting antidepressant with high efficacy. Esketamine is the S-enantiomer of ketamine, a derivative of phencyclidine developed in 1956. Esketamine exerts its effect by targeting the glutaminergic system the glutaminergic system. In this paper, we discuss the current depression treatment strategies with a focus on the pharmacology and mechanism of action of esketamine. In addition, studies reporting use of esketamine to treat perioperative depressive symptoms are reviwed, and the potential future applications of the drug are presented.

8.
Nanoscale ; 16(21): 10441-10447, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38742531

ABSTRACT

ZnSeTe quantum dots (QDs) have been employed as promising emitters for blue QD-based light-emitting diodes (QLEDs) due to their unique optoelectronic properties and environmental friendliness. However, such QLEDs usually suffer from serious efficiency roll-off primarily stemming from exciton loss at the interface of the QD layer and the ZnMgO (ZMO) electron transport layer (ETL), which remarkably hinders their application in flat-panel displays. Herein, we propose an in situ hybridization strategy that involves the pre-introduction of amino alcohols into the reaction solution. This strategy effectively suppresses the nucleophilic condensation process by facilitating the coordination of ammonium and hydroxyl groups with metal cations (M2+, i.e. Zn2+ and Mg2+). It slows down the growth rate of ZMO nanoparticles (NPs) while simultaneously facilitating M-O coordination, resulting in the synthesis of small-sized and low-defect ZMO NPs. Notably, this in situ hybridization approach not only alleviates emission quenching at the QDs/ETL interface but also elevates the energy level of the ETL for enhancing carrier injection. We further investigated the impact of amino alcohols with varying carbon-chain lengths on the performance of ZMO NPs and the corresponding LED devices. The optimal blue ZnSeTe QLED demonstrates an impressive EQE of 8.6% with only an ∼11% drop when the current density is increased to 200 mA cm-2, and the device operating lifetime extends to over 1300 h. Conversely, the device utilizing traditionally post-treated ZMO NPs as the ETL exhibits 45% efficiency roll-off and device lifetime of merely 190 h.

9.
J Immunol ; 212(12): 1945-1957, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38700419

ABSTRACT

The cytosolic detection of pathogen-derived nucleic acids has evolved as an essential strategy for host innate immune defense in mammals. One crucial component in this process is the stimulator of IFN genes (STING), which acts as a vital signaling adaptor, connecting the cytosolic detection of DNA by cyclic GMP-AMP (cGAMP) synthase (cGAS) to the downstream type I IFN signaling pathway. However, this process remains elusive in invertebrates. In this study, we present evidence demonstrating that STING, an ortholog found in a marine invertebrate (shrimp) called Litopenaeus vannamei, can directly detect DNA and initiate an IFN-like antiviral response. Unlike its homologs in other eukaryotic organisms, which exclusively function as sensors for cyclic dinucleotides, shrimp STING has the ability to bind to both double-stranded DNA and cyclic dinucleotides, including 2'3'-cGAMP. In vivo, shrimp STING can directly sense DNA nucleic acids from an infected virus, accelerate IFN regulatory factor dimerization and nuclear translocation, induce the expression of an IFN functional analog protein (Vago4), and finally establish an antiviral state. Taken together, our findings unveil a novel double-stranded DNA-STING-IKKε-IRF-Vago antiviral axis in an arthropod, providing valuable insights into the functional origins of DNA-sensing pathways in evolution.


Subject(s)
Membrane Proteins , Animals , Membrane Proteins/metabolism , Membrane Proteins/immunology , Penaeidae/immunology , Penaeidae/virology , Immunity, Innate/immunology , Signal Transduction/immunology , Interferons/metabolism , Interferons/immunology , Nucleotides, Cyclic/metabolism , Nucleotides, Cyclic/immunology
10.
Clin Cosmet Investig Dermatol ; 17: 953-959, 2024.
Article in English | MEDLINE | ID: mdl-38699407

ABSTRACT

Squamous cell carcinoma (SCC) in situ can occur on any skin or mucus surface and is more commonly found in elderly patients on areas of skin that have been sunburnt. Most previous case reports are from dermatologists, with few published reports from pathologists. In this study, three patients underwent pathological routine and auxiliary immunohistochemical (IHC) examination and were ultimately diagnosed with pagetoid SCC in situ - a different diagnosis from the initial clinical assessment. All three patients received a complete resection of the skin mass. After follow-up, as of June 2023, the patients had no tumour recurrence or metastasis. Pagetoid SCC in situ is a particular type of SCC in situ that has no specific features in clinical manifestations, gross diagnosis or histopathological sections. The final diagnosis depends on IHC staining. Pagetoid SCC in situ expresses EMA, CK5/6 and p63 but not CEA, CK8 or S-100, which are expressed in extramammary Paget's disease. Pagetoid SCC in situ is usually only locally invasive, and the main treatment is complete surgical resection. The prognosis is related to human papillomavirus infection, surgical margin closure, disease location, tumour thickness and other factors.

11.
Chem Asian J ; : e202400143, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38709124

ABSTRACT

The loss of function after prolonged periods of use is inevitable for all materials including plastics. Hence, self-healing capabilities are a key development to prolong the service lifetime of materials. One of such self-healing capabilities can be achieved by integrating dynamic bonds such as boronic ester linkages into polymeric materials, however the rate of self-healing in these materials is insufficient and current methods to accelerate it are limited. In this study, we report the rational design, synthesis and characterization of a fluorinated elastomer (FBE15) that utilizes enhanced interaction between polymer chains afforded by strong dipole-dipole interactions from -CF3, which showed a significant increase in binding energy to -7.71 Kcal/mol from -5.51 Kcal/mol, resulting in increased interaction between the boronic ester linkages and improving self-healing capabilities of boronic ester materials, drastically reducing the time required for stress relaxation by 900 %. The bulk elastomer is capable of ultrafast self-healing in a one-click fashion that can happen in mere seconds, which can then be stretched to 150 % of its original length. By utilising the dynamic cross-linking, FBE15 is also capable of both mechanical reprocessing into the same materials and chemical recycling into its starting materials, respectively, further allowing reconstruction of the elastomers that have comparable properties to the original ones at the end of its service lifespan.

12.
Opt Lett ; 49(10): 2641-2644, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748125

ABSTRACT

Mid-infrared (MIR) Si-based optoelectronics has wide potential applications, and its design requires simultaneous consideration of device performance optimization and the feasibility of heterogeneous integration. The emerging interest in all-dielectric metasurfaces for optoelectronic applications stems from their exceptional ability to manipulate light. In this Letter, we present our research on an InSb all-dielectric metasurface designed to achieve ultrahigh absorptivity within the 5-5.5 µm wavelength range. By integrating an InSb nanodisk array layer on a Si platform using wafer bonding and heteroepitaxial growth, we demonstrate three kinds of metasurface with high absorptivity of 98.36%, 99.28%, and 99.18%. The enhanced absorption is mainly contributed by the Kerker effect and the anapole state and the peak, with the added flexibility of tuning both the peak and bandwidth of absorption by altering the metasurface parameters. Our findings provide an alternative scheme to develop high-performance detectors and absorbers for MIR silicon photonics.

13.
Plants (Basel) ; 13(9)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38732415

ABSTRACT

Phytochemical investigation of the bark of Cryptomeria japonica led to the isolation of five new abietane diterpenoids, 5-epi-12-hydroxy-6-nor-5,6-secoabieta-8,11,13-trien-7,5-olide (1), 12-hydroxy-6ß-methoxy-6,7-secoabieta-8,11,13-trien-7,6-olide (2), 6ß,12-dihydroxy-7,8-secoabieta-8,11,13-trien-7,8-olide (4), 5,12-dihydroxy-7,8-secoabieta-8,11,13-trien-7,8-olide (5), and 5α,8-epoxy-12-hydroxy-7,8-secoabieta-8,11,13-trien-7-al (6), together with one known abietane diterpenoid, obtuanhydride (3). Their structures were elucidated by analysis of spectroscopic data and comparison with the spectral data of known analogs. At the concentration of 100 µg/mL, compounds 4, 5, and 6 inhibited antifungal activities against wood decay fungi activity by 18.7, 37.2, and 46.7%, respectively.

14.
Commun Biol ; 7(1): 586, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38755285

ABSTRACT

Bats serve as reservoirs for numerous zoonotic viruses, yet they typically remain asymptomatic owing to their unique immune system. Of particular significance is the MHC-I in bats, which plays crucial role in anti-viral response and exhibits polymorphic amino acid (AA) insertions. This study demonstrated that both 5AA and 3AA insertions enhance the thermal stability of the bat MHC-I complex and enrich the diversity of bound peptides in terms of quantity and length distribution, by stabilizing the 310 helix, a region prone to conformational changes during peptide loading. However, the mismatched insertion could diminish the stability of bat pMHC-I. We proposed that a suitable insertion may help bat MHC-I adapt to high body temperatures during flight while enhancing antiviral responses. Moreover, this site-specific insertions may represent a strategy of evolutionary adaptation of MHC-I molecules to fluctuations in body temperature, as similar insertions have been found in other lower vertebrates.


Subject(s)
Chiroptera , Histocompatibility Antigens Class I , Animals , Histocompatibility Antigens Class I/metabolism , Histocompatibility Antigens Class I/chemistry , Histocompatibility Antigens Class I/genetics , Protein Stability , Peptides/chemistry , Peptides/metabolism , Amino Acids/chemistry , Amino Acids/metabolism , Antigen Presentation , Mutagenesis, Insertional
15.
Article in English | MEDLINE | ID: mdl-38761998

ABSTRACT

BACKGROUND: Previous study implied that local M2 polarization of macrophage promoted mucosal edema and exacerbates Th2 type inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP). However, the specific pathogenic role of M2 macrophages and the intrinsic regulators in the development of CRS remains elusive. OBJECTIVE: We thought to investigate the regulatory role of SIRT5 in the polarization of M2 macrophages and its potential contribution to the development of CRSwNP. METHODS: RT-qPCR and Western blot analyses were performed to examine the expression levels of SIRT5 and markers of M2 macrophages in sinonasal mucosa samples obtained from both CRS and control groups. Wild-type and Sirt5 knockout mice were used to establish nasal polyp model with Th2 inflammation and investigate the effects of SIRT5 in macrophages on disease development. Furthermore, in vitro experiments were conducted to elucidate the regulatory role of SIRT5 in polarization of M2 macrophages. RESULTS: Clinical investigations showed that SIRT5 was highly expressed and positively correlated with M2 macrophages markers in eosinophilic polyps. The expression of SIRT5 in M2 macrophages was found to contribute to the development of the disease, which was impaired in Sirt5 deficiency mice. Mechanistically, SIRT5 was shown to enhance the alternative polarization of macrophages through promoting glutaminolysis. CONCLUSIONS: SIRT5 plays a crucial role in promoting the development of CRSwNP by supporting the alternative polarization of macrophage and thus provides a potential target for CRSwNP interventions.

16.
Sci Total Environ ; 932: 173033, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38723954

ABSTRACT

Microplastics (MPs) pollution has emerged as a global concern, and wastewater treatment plants (WWTPs) are one of the potential sources of MPs in the environment. However, the effect of polyethylene MPs (PE) on nitrogen (N) removal in moving bed biofilm reactor (MBBR) remains unclear. We hypothesized that PE would affect N removal in MBBR by influencing its microbial community. In this study, we investigated the impacts of different PE concentrations (100, 500, and 1000 µg/L) on N removal, enzyme activities, and microbial community in MBBR. Folin-phenol and anthrone colorimetric methods, oxidative stress and enzyme activity tests, and high-throughput sequencing combined with bioinformation analysis were used to decipher the potential mechanisms. The results demonstrated that 1000 µg/L PE had the greatest effect on NH4+-N and TN removal, with a decrease of 33.5 % and 35.2 %, and nitrifying and denitrifying enzyme activities were restrained by 29.5-39.6 % and 24.6-47.4 %. Polysaccharide and protein contents were enhanced by PE, except for 1000 µg/L PE, which decreased protein content by 65.4 mg/g VSS. The positive links of species interactions under 1000 µg/L PE exposure was 52.07 %, higher than under 500 µg/L (51.05 %) and 100 µg/L PE (50.35 %). Relative abundance of some metabolism pathways like carbohydrate metabolism and energy metabolism were restrained by 0.07-0.11 % and 0.27-0.4 %. Moreover, the total abundance of nitrification and denitrification genes both decreased under PE exposure. Overall, PE reduced N removal by affecting microbial community structure and species interactions, inhibiting some key metabolic pathways, and suppressing key enzyme activity and functional gene abundance. This paper provides new insights into assessing the risk of MPs to WWTPs, contributing to ensuring the health of aquatic ecosystems.


Subject(s)
Biofilms , Bioreactors , Microbiota , Nitrogen , Polyethylene , Waste Disposal, Fluid , Water Pollutants, Chemical , Nitrogen/metabolism , Bioreactors/microbiology , Water Pollutants, Chemical/analysis , Waste Disposal, Fluid/methods , Microbiota/drug effects , Microplastics , Wastewater/chemistry
17.
Food Chem X ; 22: 101463, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38798794

ABSTRACT

Houttuynia Cordata (HC) is a widely distributed plant in Asia and is used extensively for both food and medicinal purposes. A preliminary investigation found that HC is often bleached with sodium metabisulfite solution during its field processing, leading to health risks. In this study, the effects of sodium metabisulfite on the quality of HC were comprehensively evaluated using volatile and non-volatile targeted metabolomic methods. The results revealed a positive correlation between the extent of chemical composition changes and the bleaching time. These notable changes mainly occurred at the initial stage of bleaching. Subsequently, an untargeted UPLC/Q-TOF MS method was used to explore the potential chemical bleaching markers in bleached HC. The marker 1-hydroxy-3-oxodecane-1-sulfonic acid was subsequently prepared, isolated, and identified. Market sample verification further validated the accuracy and effectiveness of this marker.

18.
Ann Clin Lab Sci ; 54(2): 254-257, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38802163

ABSTRACT

OBJECTIVE: The present study aims to explore the clinicopathological characteristics of Epstein-Barr virus (EBV)-positive inflammatory follicular dendritic cell sarcoma (IFDCS; EBV+ IFDCS). CASE REPORT: The case involved a 32-year-old woman who underwent surgical resection of a splenic nodule. Histological examination and immunohistochemistry were performed using cluster of differentiation (CD) markers, and in-situ hybridization was conducted to detect EBV-encoded RNA (EBER). RESULTS: A microscopic analysis revealed neoplastic cells with various morphologies, including round, ovoid, or spindled shapes, dispersed within a prominent lymphoplasmacytic infiltrate. The tumor cells exhibited nuclear atypia, with some resembling Reed-Sternberg cells. The immunohistochemistry demonstrated focal positivity for follicular dendritic cell markers, such as CD21, CD23 and CD35, and focal negativity for other markers, including CD3, CD34, CD20, CD79a, myeloperoxidase and HMB45. Additionally, the EBER staining showed strongly positive results. The patient showed no local recurrence or metastasis during the 13-month follow-up. CONCLUSION: A comprehensive understanding of EBV+IFDCS, including its clinicopathological features and immunohistochemical characteristics, is crucial for accurate diagnosis and differential diagnosis of this rare tumor.


Subject(s)
Dendritic Cell Sarcoma, Follicular , Epstein-Barr Virus Infections , Herpesvirus 4, Human , Humans , Female , Dendritic Cell Sarcoma, Follicular/pathology , Dendritic Cell Sarcoma, Follicular/virology , Dendritic Cell Sarcoma, Follicular/diagnosis , Adult , Herpesvirus 4, Human/isolation & purification , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/pathology , Epstein-Barr Virus Infections/virology , Epstein-Barr Virus Infections/diagnosis , Splenic Neoplasms/pathology , Splenic Neoplasms/virology , Splenic Neoplasms/diagnosis , Immunohistochemistry , Inflammation/pathology , Inflammation/virology
19.
J Am Chem Soc ; 2024 May 27.
Article in English | MEDLINE | ID: mdl-38803151

ABSTRACT

Thermosets, characterized by their permanent cross-linked networks, present significant challenges in recyclability and brittleness. In this work, we explore a polarized Knoevenagel C═C metathesis reaction for the development of rigid yet tough and malleable thermosets. Initial investigation on small molecule model reactions reveals the feasibility of conducting the base-catalyzed C═C metathesis reaction in a solvent-free environment. Subsequently, thermosetting poly(α-cyanocinnamate)s (PCCs) were synthesized via Knoevenagel condensation between a triarm cyanoacetate star and a dialdehyde. The thermal and mechanical properties of the developed PCCs can be easily modulated by altering the structure of the dialdehyde. Remarkably, the introduction of ether groups into the PCC leads to a combination of high rigidity and toughness with Young's modulus of ∼1590 MPa, an elongation at break of ∼79%, and a toughness reaching ∼30 MJ m3. These values are competitive to traditional thermosets, in Young's modulus but far exceed them in ductility and toughness. Moreover, the C═C metathesis facilitates stress relaxation within the bulk polymer networks, thus rendering PCCs excellent malleability and reprocessability. This work overcomes the traditional limitations of thermosets, introducing groundbreaking insights for the design of rigid yet tough and malleable thermosets, and contributing significantly to the sustainability of materials.

20.
Nano Lett ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804892

ABSTRACT

Perovskite nanoplatelets (NPLs) show great potential for high-color-purity light-emitting diodes (LEDs) due to their narrow line width and high exciton binding energy. However, the performance of perovskite NPL LEDs lags far behind perovskite quantum dot-/film-based LEDs, owing to their material instability and poor carrier transport. Here, we achieved efficient and stable pure blue-emitting CsPbBr3 NPLs with outstanding optical and electrical properties by using an aromatic ligand, 4-bromothiophene-2-carboxaldehyde (BTC). The BTC ligands with thiophene groups can guide two-dimensional growth and inhibit out-of-plane ripening of CsPbBr3 NPLs, which, meanwhile, increases their structural stability via strongly interacting with PbBr64- octahedra. Moreover, aromatic structures with delocalized π-bonds facilitate charge transport, diminish band tail states, and suppress Auger processes in CsPbBr3 NPLs. Consequently, the LEDs demonstrate efficient and color-stable blue emissions at 465 nm with a narrow emission line width of 17 nm and a maximum external quantum efficiency (EQE) of 5.4%, representing the state-of-the-art CsPbBr3 NPL LEDs.

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