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1.
Int J Biol Macromol ; : 136167, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39357699

ABSTRACT

Yam is used as common herbal remedy in traditional Chinese medicine and is grown all over Asia. According to previous research, one of the primary bioactive components of yam is yam polysaccharide. To shed light on the mechanism of yam polysaccharide in ulcerative colitis (UC), a yam heteropolysaccharide named CYP-3a was isolated and purified using ultrasonic extraction, the trichloroacetic acid technique, DEAE cellulose-52 and a Sephadex G75 column. CYP-3a comprises rhamnus: arabinose:galactose:mannose:galacturonic acid glucuronic acid, with a molar ratio of 2.25:4.17:3.30:0.09:0.13:0.26. CCK-8 and ELISA analysis results showed that CYP-3a increased the number of dextran sodium sulphate (DSS)-induced Caco-2 cells and could reduce and inhibit their inflammatory response by lowering the amounts of secreted TNF-α and IL-6. Western blot data demonstrated that CYP-3a at various doses could suppress the endoplasmic reticulum stress-mediated apoptotic pathway generated by DSS-induced UC and down-regulate the protein levels of GRP78, CHOP and NF-κB.

2.
Ecotoxicol Environ Saf ; 285: 117136, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39353373

ABSTRACT

Bisphenol S (BPS) is widely presented and affects aging with unclear mechanisms. Here, we applied C. elegans to evaluate the effects of BPS on lifespan and healthspan and to investigate the underlying mechanisms. Both early-life and whole-life exposure to BPS at environmentally relevant doses (0.6, 6, 60 µg/L) significantly decreased lifespan, and healthspan (body bend, pharyngeal pumping, and lipofuscin accumulation). BPS exposure impaired mitochondrial structure and function, which promoted ROS production to induce oxidative stress. Furthermore, BPS increased expressions of the insulin/IGF-like signaling (IIS). Also, BPS inhibited expression of the IIS transcription factor daf-16 and its downstream anti-oxidative genes. Quercetin effectively improved BPS-induced oxidative stress byreversing BPS-regulated IIS/daf-16 pathway and anti-oxidative gene expressions. In daf-2 and daf-16 mutants, the effects of BPS and quercetin on lifespan, healthspan, oxidative stress, and anti-oxidative genes expressions were reversed, demonstrating the requirement of IIS/daf-16 for aging regulation. Molecular docking and molecular dynamics simulations confirmed the stable interaction between DAF-2 and BPS mainly via three residues (VAL1260, GLU1329, and MET1395), which was attenuated by quercetin. Our results highlighted that adverse effects of BPS on impairing lifespan and healthspan by affecting IIS/daf-16 function against mitochondrial stress, which could be inhibited by quercetin treatment. Thus, we first revealed the underlying mechanisms of BPS-induced aging and the potential treatment.

3.
Int Immunopharmacol ; 143(Pt 1): 113263, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39353391

ABSTRACT

OBJECTIVE: To investigate the effect of SO2 on Th1/Th2/Th17 cells in allergic rhinitis (AR) and the role of JAK1, 2/STAT3 signaling pathways.To Provide potential directions for the treatment of AR. METHODS: Fifteen AR patients were enrolled as the experimental group, while 15 healthy volunteers served as the normal control group. After collecting venous blood, peripheral blood mononuclear cells (PBMCs) were isolated and cultured, followed by the addition of SO2 derivatives and the JAK inhibitor Ruxolitinib. Flow cytometry was employed to assess alterations in the Th1/Th2 and Th17/Treg cell balance upon stimulation with SO2 and Ruxolitinib. qRT-PCR was utilized to detect the expression of Th1-related cytokines IL-2 and IFN-γ, Th2-related cytokines IL-4 and IL-5, Th17-related cytokines IL-17A and RORγt, as well as genes JAK1, JAK2, and STAT3. Flow cytometric cytokine analysis was conducted for quantitative assessment of the expression levels of inflammation-related cytokines in PBMC culture supernatants after stimulation. In addition, we stimulated the Jurkat T lymphocyte cell line with SO2 derivatives, added Ruxolitinib as an inhibitor, and used Western blot analysis to further determine the effects of SO2 on Th cells and the role of the JAK1,2/STAT3 signaling pathway in this process. RESULTS: Stimulation with SO2 derivatives upregulated the expression levels of Th2 cells and associated cytokines, as well as Th1 cells and associated cytokines. both AR patients and healthy individuals displayed increased percentages of Th17 cells and Th17/Treg ratios in PBMCs. The expression of IL-17A, RORγt, and IL-6 was also elevated. Under SO2 stimulation, the expression of JAK1, JAK2, STAT3, and RORγt in Jurkat cells increased. Moreover, after the application of Ruxolitinib, the JAK/STAT signaling pathway was inhibited. This led to a reduction in Th17 cells and IL-17A levels in both AR patients and healthy individuals, as well as a decrease in RORγt expression in Jurkat cells. Additionally, the expression of IL-5 decreased in healthy individuals. CONCLUSION: SO2 exposure exacerbated Th1/Th2/Th17 inflammation in AR patients and induced Th1 and Th17 inflammation in healthy individuals. The stimulatory effect of SO2 on Th17 cell differentiation could be inhibited by Ruxolitinib. This suggests that the Th17 inflammation induced by SO2 stimulation may be related to the activation of the JAK/STAT signaling pathway, and this has been confirmed in the Jurkat cell line.

4.
Front Pharmacol ; 15: 1421607, 2024.
Article in English | MEDLINE | ID: mdl-39224782

ABSTRACT

As a medicinal and edible homologous Chinese herb, Polygonatum sibiricum has been used as a primary ingredient in various functional and medicinal products. Damage to the intestinal mucosal barrier can lead to or worsen conditions such as type 2 diabetes and Alzheimer's disease. Traditional Chinese medicine and its bioactive components can help prevent and manage these conditions by restoring the integrity of the intestinal mucosal barrier. This review delves into the mode of action of P. sibiricum polysaccharide in disease prevention and management through the restoration of the intestinal barrier. Polysaccharide from P. sibiricum effectively treats conditions by repairing the intestinal mucosal barrier, offering insights for treating complex diseases and supporting the application of P. sibiricum in clinical settings.

5.
Lung Cancer (Auckl) ; 15: 135-142, 2024.
Article in English | MEDLINE | ID: mdl-39224877

ABSTRACT

Background: Pulmonary spindle cell carcinoma (PSCC), a highly malignant tumor, often exhibits cell pleomorphism, a histopathological characteristic. Owing to its extremely low incidence, atypical imaging and clinical presentations, and insufficient awareness among clinicians, PSCC is often misdiagnosed, which results in delays in treatment. Herein, we reported a rare case of PSCC that was initially misdiagnosed as granulomatous inflammation. Case Presentation: A 66-year-old male visited a local hospital with symptoms such as cough and hemoptysis. A computed tomography (CT) scan of the chest revealed a mass in his right lung, and no mediastinal lymphadenopathy was observed. Bronchoscopy showed no major abnormalities, and the results of fine needle aspiration biopsy showed granulomatous inflammation. Even though the patient received anti-infection treatment, his symptoms did not improve markedly. After two months, a follow-up CT scan of the lung showed a noticeably enlarged mass accompanied by multiple instances of mediastinal lymphadenopathy in the upper lobe of the right lung. Consequently, he underwent a second CT-guided lung biopsy at our hospital. The pathology report indicated PSCC. Due to financial constraints, genetic testing was not performed. Given his poor overall physical condition, the patient was unable to undergo systemic chemotherapy and instead received palliative radiotherapy. The prescribed radiotherapy dose for the right upper lobe lung cancer and multiple metastatic lymph nodes was 60 Gy, administered in 30 fractions. Unfortunately, he failed to adhere to scheduled follow-ups and succumbed to the disease 6 months later, as confirmed during a telephone follow-up. Conclusion: PSCC is a rare but highly malignant lung cancer. Multiple pathological biopsies are necessary to accurately and promptly diagnose the disease, which is crucial for early treatment intervention as well as improving patient prognosis.

7.
Cell Discov ; 10(1): 95, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39251570

ABSTRACT

Deep learning-based methods for generating functional proteins address the growing need for novel biocatalysts, allowing for precise tailoring of functionalities to meet specific requirements. This advancement leads to the development of highly efficient and specialized proteins with diverse applications across scientific, technological, and biomedical fields. This study establishes a pipeline for protein sequence generation with a conditional protein diffusion model, namely CPDiffusion, to create diverse sequences of proteins with enhanced functions. CPDiffusion accommodates protein-specific conditions, such as secondary structures and highly conserved amino acids. Without relying on extensive training data, CPDiffusion effectively captures highly conserved residues and sequence features for specific protein families. We applied CPDiffusion to generate artificial sequences of Argonaute (Ago) proteins based on the backbone structures of wild-type (WT) Kurthia massiliensis Ago (KmAgo) and Pyrococcus furiosus Ago (PfAgo), which are complex multi-domain programmable endonucleases. The generated sequences deviate by up to nearly 400 amino acids from their WT templates. Experimental tests demonstrated that the majority of the generated proteins for both KmAgo and PfAgo show unambiguous activity in DNA cleavage, with many of them exhibiting superior activity as compared to the WT. These findings underscore CPDiffusion's remarkable success rate in generating novel sequences for proteins with complex structures and functions in a single step, leading to enhanced activity. This approach facilitates the design of enzymes with multi-domain molecular structures and intricate functions through in silico generation and screening, all accomplished without the need for supervision from labeled data.

8.
Medicine (Baltimore) ; 103(36): e39655, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39252214

ABSTRACT

Previous studies have confirmed the affiliation between specific inflammatory cytokines and Hepatic fibrosis (HF); however, contradictions remain in the causality. The study implemented a bidirectional two-sample Mendelian randomization (MR) analysis with published statistics derived from Genome-wide Association Studies (GWAS) to investigate casualties between inflammatory cytokines and HF. Additionally, MR analysis was also introduced to consider if 1400 blood metabolites act as the key mediators in this process. Single nucleotide polymorphisms (SNPs) with strong correlations to inflammatory factors were selected for multiple MR analyses in this study. The inverse variance weighted method (IVW) was chosen as the principal analysis, and the others as the supportive. Besides, sensitivity tests were involved to identify potential heterogeneity and pleiotropic level. IVW methods revealed that a relatively high level of prediction-based monocyte chemoattractant protein-4 (MCP-4) (95% CI: 1.014-3.336, P = .045), along with neurturin (NRTN) (95% CI: 1.204-4.004, P = .010), may increase the risk of HF; while programmed cell death 1 ligand 1 (PD-L1) (95% CI: 0.223-0.928, P = .030), showed a protective effect on HF. No significant statistical differences were detected on any other inflammatory cytokines, nor did the impact of HF genetic predisposition on the 91 circulating inflammatory cytokines-related characteristics.


Subject(s)
B7-H1 Antigen , Genome-Wide Association Study , Liver Cirrhosis , Mendelian Randomization Analysis , Polymorphism, Single Nucleotide , Humans , Liver Cirrhosis/genetics , Liver Cirrhosis/blood , B7-H1 Antigen/genetics , B7-H1 Antigen/blood , Genetic Predisposition to Disease
9.
J Psychosom Res ; 187: 111913, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39260138

ABSTRACT

OBJECTIVE: This study aimed to explore the mediating roles of mindfulness and illness perception in the effects of a social media-based Mindfulness psyCho-behAvioRal intErvention (MCARE) on depressive and anxiety symptoms among patients with ACS. METHODS: This study conducted a secondary longitudinal mediation analysis using data from a randomized controlled trial of the MCARE grogram in patients with ACS. Participants were recruited at two tertiary hospitals in Jinan, China. The MCARE program consisted of six weekly sessions addressing mindfulness training and disease management to facilitate understanding and management of emotions and illness. The analytical sample included participants who completed measures of the primary outcomes, i.e., depression (PHQ-9) and anxiety (GAD-7) and potential mediators, i.e., mindfulness (CAMS-R) and illness perception (Brief-IPQ) at baseline (T0), immediate post-intervention (T1), and 12-week after the commencement of the intervention (T2). RESULTS: This study included 146 participants (mean age 58.9 years (SD = 8.9), 69.2 % male), including both intervention and control groups. The mediation analysis revealed a significant mediating effect of T1 mindfulness in the relationship between the group and T2 depression symptoms (indirect effect: -0.109, 95 % CI: -0.191, -0.041; P = 0.004), accounting for 26 % of the effect. For T2 anxiety symptoms, T1 illness perception exhibited a significant mediating effect (indirect effect: -0.055, 95 % CI: -0.110, -0.005; P = 0.035), accounting for 22 % of the effect. CONCLUSIONS: This study found that mindfulness and illness perception played a mediating role in the effects of the MCARE program on depressive and anxiety symptoms among patients with ACS.

11.
bioRxiv ; 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39282450

ABSTRACT

Transcription factor deregulation potently drives melanoma progression by dynamically and reversibly controlling gene expression programs. We previously identified the small MAF family transcription factor MAFG as a putative driver of melanoma progression, prompting an in-depth evaluation of its role in melanoma. MAFG expression increases with human melanoma stages and ectopic MAFG expression enhances the malignant behavior of human melanoma cells in vitro, xenograft models, and genetic mouse models of spontaneous melanoma. Moreover, MAFG induces a melanoma phenotype switch from a melanocytic state to a more dedifferentiated state. Mechanistically, MAFG interacts with the lineage transcription factor MITF which is required for the pro-tumorigenic effects of MAFG. MAFG and MITF co-occupy numerous genomic sites and MAFG overexpression influences the expression of genes harboring binding sites for the MAFG~MITF complex. These results establish MAFG as a potent driver of melanomagenesis through dimerization with MITF and uncover an unappreciated mechanism of MITF regulation.

12.
Adv Sci (Weinh) ; : e2403442, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39297413

ABSTRACT

Effective inhibition of intestinal lipid uptake is an efficient strategy for the treatment of disorders related to lipid metabolism. Sterol O-acyltransferase 2 (SOAT2) is responsible for the esterification of free cholesterol and fatty acids into cholesteryl esters. We found that intestine-specific SOAT2 knockout (Soat2I-KO) mice was capable to prevent the development of dietary induced obesity due to reduced intestinal lipid absorption. Soat2 siRNA/CS-PLGA nanoparticle system was constructed to enable intestinal delivery and inhibition of Soat2. This nanoparticle system was composed of PLGA-block-PEG and chitosan specifically delivering Soat2 siRNAs into small intestines in mice, effectively inhibit intestinal lipid uptake and resolving obesity. In revealing the underlying mechanism by which intestinal SOAT2 regulating fatty acid uptake, enhanced CD36 ubiquitination degradation was found in enterocytes upon SOAT2 inhibition. Insufficient free cholesterol esterification promoted endoplasmic reticulum stress and recruitment of E3 ligase RNF5 to activate CD36 ubiquitination in SOAT2 knockdown enterocytes. This work demonstrates a potential modulatory function of intestinal SOAT2 on lipid uptake highlighting the therapeutic effect on obesity by targeting intestinal SOAT2, exhibiting promising translational relevance in the siRNA therapeutic-based treatment for obesity.

13.
BMC Geriatr ; 24(1): 775, 2024 Sep 20.
Article in English | MEDLINE | ID: mdl-39304854

ABSTRACT

BACKGROUND: Anemia frequently occurs in patients with hip fractures and represents a risk factor that can potentially be altered. To evaluate the association between admission anemia and complications in older hip fracture patients while exploring the potential impact of anemia on complications from the perspective of overall, operation and non-operation. METHODS: This retrospective study enrolled in-patients over 60 years old with hip fractures from January 2020 to November 2023. At admission, anemic patients were identified as having a hemoglobin level below 12 g/dL in females and 13 g/dL in males. Anemia was further classified as mild, moderate, or severe. Data encompassing demographics, comorbidities, medications, information on fracture and surgery, and complications were collected. RESULTS: A total of 462/679 patients had anemia, including 348, 105, and 9 with mild, moderate, and severe anemia, respectively. A total of 281 individuals experienced complications, including 212 and 69 with and without operation, respectively. Multivariate regression analysis identified anemia as a greater risk for acute heart failure (OR = 2.056, p = 0.037, 95% CI 1.043-4.052) than non-anemia. Moderate to severe anemia was a significant risk factor for any complication (OR = 1.584, p = 0.028, 95% CI 1.050-2.390), ≥ 2 (OR = 2.364, p = 0.001, 95% CI 1.443-3.872) or 3 (OR = 2.311, p = 0.022, 95% CI 1.131-4.720) complications, delirium (OR = 2.301, p = 0.018, 95% CI 1.156-4.579), venous thromboembolism (OR = 2.031, p = 0.042, 95% CI 1.025-4.025), and acute heart failure (OR = 2.095, p = 0.016, 95% CI 1.145-3.834), compared with mild to non-anemia. Similar results were observed in operated patients, while anemia and its severity were not associated with complications in non-operated patients. CONCLUSION: Moderate to severe anemia caused complications in elderly hip fracture patients, but it was not observed in non-operated individuals. These findings would support orthopedic physicians' hierarchical management of anemic patients.


Subject(s)
Anemia , Hip Fractures , Humans , Hip Fractures/epidemiology , Hip Fractures/complications , Male , Female , Anemia/epidemiology , Anemia/complications , Aged , Retrospective Studies , Aged, 80 and over , Risk Factors , Middle Aged , Severity of Illness Index , Postoperative Complications/epidemiology , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Heart Failure/epidemiology , Heart Failure/complications
14.
J Hazard Mater ; 480: 135908, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39307015

ABSTRACT

Comprehensive site investigation techniques, including Electrical Resistivity Tomography (ERT), Induced Polarization (IP), Multichannel Analysis of Surface Waves (MASW), and Microtremor Array Method (MAM), were integrated with geotechnical and geochemical tests of retrieved waste samples from Singapore's operational offshore landfill. The properties of landfill wastes vary widely, including shear-wave velocities 127-248 m/s, densities 1.2-2.1 Mg/m3, resistivity 3.0-25.3 Ω∙m, and chargeability 48-82 mV/V. The natural clay layer underneath was clearly delineated and effectively mitigated leachate leakage. K-means clustering of the geophysical data facilitates precise mapping of waste distribution and quantities of recoverable metals based on quantitative criteria. This study illustrates a thorough case study adopting the new site investigation and characterization paradigm for an offshore landfill, which provides insights into leachate leakage detection and evaluations of landfill mining and resource recovery.

15.
Asian J Surg ; 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39307644
16.
Int J Biol Macromol ; 280(Pt 1): 135767, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39299425

ABSTRACT

To establish the quality control method of Dioscorea opposita Thunb., the multi-level fingerprinting of polysaccharides was established and the relationship between fingerprint and immune activity was analyzed. The two molecular weight segments Mw1 (1.38 × 105-1.63 × 106 Da) and Mw2 (3.27 × 103-4.37 × 103 Da), thirteen infrared absorption peaks (3399.26 cm-1, 2929.32 cm-1, 1631.78 cm-1, 1400.39 cm-1, 1351.80 cm-1, 1123.58 cm-1, 1024.76 cm-1, 931.53 cm-1, 854.76 cm-1, 760.43 cm-1, 708.14 cm-1, 616.47 cm-1, and 526.78 cm-1), and four monosaccharides (Man, Rha, GalA, and Glc) were used to evaluate the quality of Dioscorea opposita Thunb. The molecular weight fragments of Mw1, FT-IR absorption peaks of 1631.78 cm-1, and two monosaccharides (Man and Glc) would be used to identify Dioscorea opposita Thunb. polysaccharide (DOP) from different origins. The relationship of spectrum-effect showed that polysaccharides with features such as higher Mw1, a lower peak height of 1631.78 cm-1, higher content of Man, and lower content of Glc exerted stronger immune activity. In conclusion, this study established a polysaccharide-based quality evaluation method for Dioscorea opposita Thunb. and explored the relationship between polysaccharide fingerprints and in vitro immune activity, which provided a basis for further research on Dioscorea opposita Thunb.

17.
Int J Mol Med ; 54(6)2024 Dec.
Article in English | MEDLINE | ID: mdl-39301662

ABSTRACT

Liver fibrosis is a pathophysiologic manifestation of chronic liver disease and a precursor to cirrhosis and hepatocellular carcinoma. Glycolysis provides intermediate metabolites as well as energy support for cell proliferation and phenotypic transformation in liver fibers. 6­Phosphofructo­2­kinase/fructose­2,6­bisphosphatase 3 (PFKFB3) is a key activator of glycolysis and plays an important role in the process of glycolysis. The role of PFKFB3­mediated glycolysis in myocardial fibrosis, renal fibrosis and pulmonary fibrosis has been demonstrated, and the role of PFKFB3 in the activation of hepatic stellate cells by aerobic glycolysis has been proven by relevant experiments. The present study reviews the research progress on the role and mechanism of action of PFKFB3­mediated glycolysis in the progression of hepatic fibrosis to discuss the role of PFKFB3­mediated glycolysis in hepatic fibrosis and to provide new ideas for research on PFKFB3 as a target for the treatment of hepatic fibrosis.


Subject(s)
Glycolysis , Liver Cirrhosis , Phosphofructokinase-2 , Phosphofructokinase-2/metabolism , Phosphofructokinase-2/genetics , Humans , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Animals
18.
Heart Lung ; 68: 359-366, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39260267

ABSTRACT

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death worldwide, particularly affecting low- and middle-income countries. Food environments may be linked with the risk of CVD; however, current study findings regarding their relationship are inconsistent. A systematic review of their associations is needed to guide interventions to improve cardiovascular health. OBJECTIVE: This systematic review aimed to comprehensively assess the relationship between food environments and CVD outcomes, including incidence, hospitalization, mortality, and recurrence rates. METHOD: According to PRISMA guidelines, a systematic search was conducted until 28th March 2024, using eight databases, including PubMed, Embase, Ovid, CINAHL, Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Data. The review quality was assessed according to the Agency for Healthcare Research and Quality (AHRQ) and Newcastle-Ottawa Scale (NOS). The included studies were categorized based on their exposure factors into unhealthy, healthy, and comprehensive food environments, encompassing facilities that offer healthy and unhealthy foods. The findings were narratively synthesized according to this classification. RESULT: A total of 23 studies, encompassing 13 cross-sectional studies and 10 cohort-longitudinal studies, were included in this review. Among the 20 studies on unhealthy food environments, 13 found a positive association with CVD outcomes. Of the seven studies on healthy food environments, 3 found a negative association with CVD outcomes. Additionally, 4 out of 8 studies on comprehensive food environments found a significant but inconsistent association with CVD outcomes. CONCLUSION: This study suggested that unhealthy food environments are probably associated with CVD outcomes. At the same time, there is currently no conclusive evidence to indicate a relationship between healthy food environments or comprehensive food environments and CVD outcomes.

19.
Angew Chem Int Ed Engl ; : e202415318, 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39305146

ABSTRACT

AgGaS2 (AGS) is the most commonly used commercial infrared nonlinear optical material. However, AGS has a narrow band gap (Eg = 2.58 eV) and a low laser-induced damage threshold (LIDT), primarily attributed to its mobile liquid-like Ag+ constituent and the unstable Ag-S chemical bond. Herein, we propose a "band reformation of AGS" strategy, which leads to the success syntheses of four lanthanide sulfides, LiLnGeS4, crystalizing in an asymmetric Ama2 structure. LiLaGeS4 demonstrates that eliminating the presence of Ag-4d band increases the Eg to 3.32 eV and enhances the LIDT (14-29 × AGS, measured by both powder and single crystal); while increasing the nonbonding density of states of the S-3p band enhances the 2nd-nonlinear optical coefficient (1.06 × AGS). Besides, the bond length discrepancy between [LiS4], [GeS4] and [LaS8] units leads to a moderate birefringence (Δn = 0.052). Such a unique structure further results in extremely small thermal expansion with αL = 0.41-1.74 × 10-5 K-1, along different crystallographic axes. Our theoretical studies indicate that the synergy of the structure building units contribute to the second harmonic generation performance. These results suggest that the "band reformation of AGS" strategy provides effective guidance to discover new NLO crystals with optimized performance.

20.
Chemistry ; : e202402745, 2024 Sep 21.
Article in English | MEDLINE | ID: mdl-39305279

ABSTRACT

Acenes are notable for their optoelectronic properties. Starphenes are structurally related molecules possessing three acene arms that radiate linearly from a central benzene ring (i.e., linearly annellated triphenylenes). Large starphenes have been prepared using convergent syntheses involving transition metal catalyzed cyclotrimerizations of either preformed acenes or arynes. Here, we report a one-pot divergent synthesis of a 13-ring triquinone that readily converts to a [4.4.4]tridecastarphene derivative. The one-pot procedure involves the sequential reactions of three 1,4-anthraquinones with o--quinodimethane derivatives that are generated sequentially from a trisulfone precursor. The resulting [4.4.4]tridecastarphene derivative bearing p-(t-butyl)phenyl substituents was characterized by 1H NMR, 13C NMR and UV-vis spectroscopies, as well as mass spectrometry, cyclic voltammetry, differential pulse voltammetry and DFT calculations. Theoretical and experimental studies reveal a relatively high-lying HOMO orbital (about -4.70 to -4.86 eV) and a relatively small HOMO-LUMO gap (2.1 eV), suggesting utility as a p-type organic semiconductor. Our [4.4.4]tridecastarphene photooxidizes in CH2Cl2 solution exposed to ambient light and air with a half-life of 150 minutes at room temperature, but shows no sign of degradation after 12 months in the solid-state. Our [4.4.4]tridecastarphene shows excellent solubility in various organic solvents including dichloromethane, chloroform and toluene, potentially enabling printed electronic applications.

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