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1.
J Org Chem ; 89(16): 11195-11202, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39067013

RESUMEN

A high-efficiency tandem process has been developed for the formation of two C-N bonds through a cross-dehydrogenative coupling (CDC) amination of spiro[acridine-9,9'-fluorene]s (SAFs) with amines. This method offers a strategically innovative and atom-economical approach to obtaining diamine-substituted SAFs. Notably, the approach eliminates the need for metal catalysts and other additives, relying solely on O2 as the oxidant. A self-activation mechanism has been proposed to elucidate the effective double amination in the CDC process.

2.
BMC Cardiovasc Disord ; 24(1): 108, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355458

RESUMEN

BACKGROUND: Clinical characteristics and long-term data on the safety and efficacy of LAAC in preventing cerebrovascular accident and thromboembolism among Chinese patients with non-valvular AF (NVAF) remain limited. METHODS: Data of consecutive NVAF patients who underwent LAAC at Beijing Anzhen Hospital, Capital Medical University, from June 1, 2014, to December 31, 2021, were collected and analyzed retrospectively. The primary effectiveness endpoint was the composite endpoint of stroke/transient ischemic attack, systemic embolism, and death from cardiovascular causes. The primary safety endpoint is the severe bleeding defined by the LAAC Munich consensus. RESULTS: Of the 222 patients enrolled, the mean age was 66.90 ± 9.62 years, with a majority being male (77.03%). Many patients are non-paroxysmal AF (71.19%) with a median duration of AF of 4.00 years. The mean CHA2DS2-VASc score was 3.78 ± 1.49, and the mean HAS-BLED score was 1.68 ± 0.86. Thromboembolic events (76.58%) were the most common indication for LAAC. The device, technical, and procedural success rates were 98.65%, 98.65%, and 93.69%, respectively. The anticoagulation continuation rate was 56.36%, 31.25%, and 22.60% at 3-, 6- and 12 months post-procedure, respectively. Throughout a mean 2.81 years of follow-up, the incidence of the primary efficacy endpoint was 4.27 per 100 patient-years, predominantly attributable to stroke/TIA (3.12 per 100 PYs). Five patients experienced major bleeding during the follow-up period. Post-procedure imaging revealed minimal complications, with only one substantial peri-device leak. Device-related thrombus occurred in 2.33% of patients, resolving with anticoagulation. CONCLUSION: The study demonstrates that LAAC is a safe and effective alternative option for Chinese patients with AF, with a high success rate, few complications as well as fewer long-term adverse outcome events.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Accidente Cerebrovascular , Tromboembolia , Humanos , Masculino , Persona de Mediana Edad , Anciano , Femenino , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/tratamiento farmacológico , Resultado del Tratamiento , Cierre del Apéndice Auricular Izquierdo , Estudios Retrospectivos , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Hemorragia/inducido químicamente , Tromboembolia/epidemiología , Tromboembolia/etiología , Tromboembolia/prevención & control , Anticoagulantes/efectos adversos , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía
3.
Rev Cardiovasc Med ; 24(3): 71, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39077478

RESUMEN

Background: Inflammatory cells and remnant cholesterol (RC) play an important role in the development and progression of cardiovascular diseases. In order to understand their contribution to cardiovascular diseases, we proposed the RC to lymphocyte ratio (RCLR) that reflects the level of serum lipid and inflammation as a predictive indicator. In this study, we explored the correlation between RCLR and major adverse cardiovascular events (MACEs) in patients with unstable angina (UA) treated with percutaneous coronary intervention (PCI). Methods: RCLR was calculated by dividing RC by lymphocyte percentage. Patients were divided into four groups according to RCLR quartiles. The endpoint of the study was MACE, a composite endpoint including all-cause mortality, non-fatal myocardial infarction (MI), and ischemia­driven revascularization. The multivariable Cox proportional hazard model was used to determine the exclusive effect of RCLR on MACE. Results: The study was conducted on 1092 patients with UA. The rate of MACE increased as RCLR quartiles increased (quartile 4 vs quartile 1: 40.9% vs 9.2%, p < 0.001). An adjustment for confounding variables revealed that an increase in the rate of MACE was directly proportional to RCLR (quartile 4 vs quartile 1: HR - 5.85 [95% CI, 3.77-9.08], p < 0.001, p for trend < 0.001). Conclusions: RCLR independently correlated with the incidence of MACE in patients with UA treated with PCI.

4.
Pacing Clin Electrophysiol ; 46(9): 1124-1133, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37578003

RESUMEN

The incidence of silent cerebral emboli (SCE) associated with atrial fibrillation catheter ablation (AFCA) is much higher than that of stroke/transient ischemic attack (TIA). Interventional electrophysiologists have been increasingly alerted to asymptomatic cerebral infarction over the years. Plentiful studies revealed that diagnostic definitions, detection modalities, energy sources, ablation strategies, perioperative anticoagulation regimens, and patient-related factors were associated with the risk of AFCA-associated SCE. Studies related to non-interventional procedures found that SCE may prompt stroke, cognitive decline, and dementia later in life, suggesting a possible role of AFCA-associated SCE in the cognitive function of patients with AF. However, there is no consistent evidence for this view to date. Given that the majority of patients with AF being elderly and the increased risk of cognitive impairment in AF itself, efforts should be made to minimize the occurrence of AFCA-associated SCE.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Embolia Intracraneal , Accidente Cerebrovascular , Humanos , Anciano , Factores de Riesgo , Embolia Intracraneal/etiología , Accidente Cerebrovascular/etiología , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Resultado del Tratamiento
5.
Ecotoxicol Environ Saf ; 249: 114447, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38321666

RESUMEN

Phycotoxins are a class of multiple natural metabolites produced by microalgae in marine and freshwater ecosystems that bioaccumulate in food webs, particularly in shellfish, having a great impact on human health. Phycotoxins are mainly leached and absorbed in the small intestine when human consumers accidentally ingest toxic aquatic products contaminated by them. To assess the intestinal uptake and damage of phycotoxins, a typical in vitro model was developed and widely applied using the human colorectal adenocarcinoma Caco-2 cell line. In this review, the application cases were summarized for multiple phycotoxins, including microcystins (MCs), cylindrospermopsins (CYNs), domoic acids (DAs), saxitoxins (STXs), palytoxins (PLTXs), okadaic acids (OAs), pectenotoxins (PTXs) and azaspiracids (AZAs). The results of the previous studies showed that each group of phycotoxins presented different cytotoxicity and mechanisms to Caco-2 cells, and significant discrepancies in the transport of phycotoxin across the Caco-2 cell monolayers. Therefore, this review describes the evaluation assays of the Caco-2 cell monolayer model, illustrates the principles of several primary cytotoxicity evaluation assays, and summarizes the cytotoxicity of each group of phycotoxins to Caco-2 cells line and their cellular transport, and finally proposes the development of multicellular intestinal models for future comprehensive studies on the toxicity and absorption of phycotoxins in the intestine. It will improve the understanding of Caco-2 cell monolayer models in the toxicology studies on phycotoxins and the potentially detrimental effects of microalgal toxins on the human intestine.


Asunto(s)
Ecosistema , Microalgas , Humanos , Células CACO-2 , Funcion de la Barrera Intestinal , Toxinas Marinas/toxicidad , Ácido Ocadaico/toxicidad
6.
Luminescence ; 38(5): 518-526, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36882911

RESUMEN

The abuse of sulfameter (SME) in animal husbandry can cause drug resistance and toxic or allergic reactions in humans. Therefore, it is very important to establish a simple, inexpensive, and efficient method for detecting SME in food. In this work, we propose a single fluorescent aptamer/graphene oxide (GO)-based biosensor to detect SME residues in milk. Aptamers that specifically bind to SME were screened using capture-SELEX and a ssDNA library immobilized on magnetic beads. The 68 active candidate aptamers were chemically synthesized for specificity and affinity characterization. Among the aptamers, the aptamer sulf-1 revealed the highest affinity (Kd = 77 ± 15 nM) to SME and was selected to construct a GO-based fluorescent biosensor for real milk sample detection. Under optimal conditions, the single fluorescent aptasensor had a wide linear range (R2 was 0.997) from 7 to 336 ng/ml and a low detection limit of 3.35 ng/ml that was calculated with a 3SD/slope. The single fluorescent method was also validated using SME-fortified milk samples, showing average recoveries ranging from 99.01% to 104.60% with a relative standard deviation of less than 3.88%. These results demonstrate that this novel aptamer sensor provides an opportunity for sensitive, convenient, and accurate detection of SME residues in milk.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Sulfameter , Humanos , Animales , Leche/química , Sulfameter/análisis , Aptámeros de Nucleótidos/química , Alérgenos , Colorantes , ADN de Cadena Simple , Límite de Detección
7.
Transfus Apher Sci ; 61(6): 103494, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35773126

RESUMEN

BACKGROUND: Blood transfusions reportedly modulate the recipient's immune system. Transfusion-related immunomodulation has been suggested as a mechanism of some adverse clinical outcomes. Extracellular nucleic acids circulate in plasma and activate relevant immune responses, but little is known about their mechanism of action in transfusion-related immunomodulation (TRIM). The aim of this study was to investigate the effects of cell-free nucleic acids (CFNAs) produced by red blood cells (RBCs) on innate immunity, especially peripheral blood mononuclear cells (PBMCs) and macrophages, and to investigate the mechanism of action. METHODS: Differentially expressed genes (DEGs) between PBMCs exposed to RBC-produced CFNA and normal PBMCs were analyzed by gene expression data combined with bioinformatics. KEGG and GO enrichment analyses were performed for the DEGs, and in vitro experiments were performed for the effects of key genes on the release of inflammatory factors from macrophages. RESULTS: Analysis of microarray data showed that exposure of monocytes to RBC-produced CFNAs increased the expression of genes involved in the innate immune response, including chemokines, chemokine receptors, and innate response receptors, and that calcium channel activity was highly regulated, with a key gene being CaMKIV. CaMKIV played a critical role in LPS-induced inflammatory factor release from macrophages, which was exacerbated by overexpression of the CaMKIV gene. CONCLUSION: RBCs regulate the release of inflammatory factors during blood transfusion by releasing CFNAs and affecting expression of the CaMKIV gene in PBMCs or macrophages, which is a potential regulatory mechanism of blood transfusion-related immune regulation and related adverse reactions.


Asunto(s)
Ácidos Nucleicos Libres de Células , Leucocitos Mononucleares , Humanos , Ácidos Nucleicos Libres de Células/metabolismo , Eritrocitos/metabolismo , Inmunidad Innata , Macrófagos , Proteína Quinasa Tipo 4 Dependiente de Calcio Calmodulina/metabolismo
8.
Curr Microbiol ; 78(7): 2631-2639, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33991202

RESUMEN

Lamprey, one of the most basal jawless vertebrate, is an excellent model for studying vertebrate evolution, embryo development, and the origin of adaptive immunity. This study investigated the differentially expressed proteins in lamprey leukocytes in response to the co-stimulation of intestinal Aeromonas and Shewanella by using quantitative proteomics techniques. Significant differentially expressed proteins were identified. Gene Ontology annotation and the Kyoto Encyclopedia of Genes and Genomes pathway based on the significant differentially expressed proteins were analyzed. Most of the differentially expressed proteins were predicted to be involved in important signaling pathways. Quantitative real-time polymerase chain reaction was used to verify the expression of differentially expressed proteins at the mRNA level. The expression of some differentially expressed proteins was not consistent at the mRNA and protein levels. Differentially expressed proteins that are essential for lamprey-intestinal bacteria interaction should be identified to understand the lamprey adaptive immune response induced by gut microbiota.


Asunto(s)
Aeromonas , Shewanella , Aeromonas/genética , Animales , Lampreas , Leucocitos , Proteómica , Shewanella/genética
9.
Cardiology ; 145(6): 390-400, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32305978

RESUMEN

Ubiquitination is one of the basic mechanisms of cell protein homeostasis and degradation and is accomplished by 3 enzymes, E1, E2, and E3. Tripartite motif-containing proteins (TRIMs) constitute the largest subfamily of RING E3 ligases, with >70 current members in humans and mice. These members are involved in multiple biological processes, including growth, differentiation, and apoptosis as well as disease and tumorigenesis. Accumulating evidence has shown that many TRIM proteins are associated with various cardiac processes and pathologies, such as heart development, signal transduction, protein degradation, autophagy mediation, ion channel regulation, congenital heart disease, and cardiomyopathies. In this review, we provide an overview of the TRIM family and discuss its involvement in the regulation of cardiac proteostasis and pathophysiology and its potential therapeutic implications.


Asunto(s)
Enfermedades Cardiovasculares , Animales , Ratones , Transducción de Señal , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
10.
J Org Chem ; 83(8): 4824-4830, 2018 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-29595264

RESUMEN

We present a series of tripodal ligands L1-3, which fold into hemicages C1-3 by using coordination-driven dynamic combinational chemistry. The identities of these hemicages were characterized using 1H NMR, 1H-1H COSY, DOSY, and ESI-TWIM-MS. Free rotation of the ferrocene structural units in the ligands affords an adaptable directionality, which is essential for the construction of these hemicages. Encapsulation of adamantane by C2 indicates the presence of a well-defined inner cavity as the binding pocket.

11.
Aging (Albany NY) ; 16(12): 10239-10251, 2024 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-38942609

RESUMEN

BACKGROUND AND OBJECTIVES: Blood transfusion is a common therapeutic procedure in hospitalized patients. Red blood cell (RBC) units undergo various biochemical and morphological changes during storage (storage lesion). miRNAs have been studied intensively regarding cellular metabolic processes, but the effect of miRNAs on blood storage is not well defined. MATERIALS AND METHODS: We performed bioinformatics analysis on the public data set of miRNA expression of RBC based on R language, and performed the Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis on the target genes of differentially expressed miRNA. The expression of miRNA differential genes in blood samples stored at different times was verified by qRT-PCR. Next, we used ELISA and qRT-PCR to verify the expression of IL-1ß, IL-6, IL-12 and TNF-α in blood at day 1 and day 42. In addition, in vitro, we transfected macrophages with overexpressed miRNA, and the effects of overexpressed miRNA on macrophage polarization and the release of inflammatory factors were verified by flow cytometry and qRT-PCR and ELISA. RESULTS: This study combined bioinformatics analysis and experiments to discover the differentially expressed miRNAs in long-term stored blood. The results showed that compared to fresh blood samples, the inflammatory factors were significantly doubled by ELISA, as well as the higher mRNA expression at 42 day. Experimentally verified that miR-33a-5p promoted the M1 type macrophage polarization and increased the release of related inflammatory factors through PPARα/ACC2/AMPK/CPT-1a axis regulation. CONCLUSIONS: This study elucidates a potential mechanism of inflammatory factor accumulation in long-term stored blood, providing a theoretical basis and a potential target to prevent transfusion-related adverse reactions.


Asunto(s)
Conservación de la Sangre , Eritrocitos , Inmunidad Innata , Inflamación , MicroARNs , MicroARNs/genética , MicroARNs/metabolismo , Humanos , Inmunidad Innata/genética , Inflamación/genética , Inflamación/inmunología , Eritrocitos/metabolismo , Eritrocitos/inmunología , Regulación de la Expresión Génica , Biología Computacional , Macrófagos/metabolismo , Macrófagos/inmunología
12.
J Agric Food Chem ; 72(22): 12673-12684, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38772747

RESUMEN

Biogenic selenium nanoparticles (SeNPs) are the most favorable Se form for nutritional supplementation due to their high stability, low toxicity, and high activity. However, the interaction between the surface-binding proteins and their stable biogenic SeNPs, as well as their impact on the stability and bioavailability of SeNPs, remains to be understood. In vitro stabilization experiments revealed an amino acid segment (F(235-386)) in Rahnella aquatilis' flagellin FliC, with surfactant-like properties, stabilizing SeNPs under harsh conditions. FliC and F(235-386) were employed as stabilizers to synthesize SeNPs (FliC@SeNPs and F(235-386)@SeNPs), and surface chemistry analysis revealed coordination reactions between the proteins and Se atoms on the surface of SeNPs. Both FliC and F(235-386) enhanced SeNPs uptake in wheat seedlings but reduced it in bacteria and yeast. This study highlights FliC's core function in stabilizing SeNPs and enhancing their bioavailability, paving the way for agricultural and nutritional applications.


Asunto(s)
Disponibilidad Biológica , Flagelina , Nanopartículas , Selenio , Tensoactivos , Selenio/química , Selenio/metabolismo , Flagelina/química , Flagelina/metabolismo , Tensoactivos/química , Tensoactivos/metabolismo , Nanopartículas/química , Triticum/química , Triticum/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética
13.
Artículo en Zh | MEDLINE | ID: mdl-39118511

RESUMEN

Objective:To explore the clinical characteristics of sarcoidosis of head and neck symptoms, and to summarize the diagnosis and treatment experience. Methods:A retrospective study was conducted on patients with nodular disease with main symptoms in the head and neck who visited Henan Provincial People's Hospital from January 2020 to August 2023. The clinical data including symptom characteristics, pathological characteristics, treatment methods, and prognosis were analyzed. Results:A total of 14 patients were included, with 4 males(28.6%) and 10 females(71.4%), age ranged from 11 to 71 years, with an average age of(52.0±15.8) years. The lesions were located in the parotid gland in 2 cases and the neck in 12 cases. Twelve cases underwent neck mass resection surgery, and 2 cases underwent ultrasound-guided core biopsy of parotid gland tumor and postoperative pathological diagnosis was confirmed in all cases. Four cases received steroid treatment postoperatively, and showed good prognosis with reduced lesion size after 3 months. Three cases did not take medication and the lesions continued to persist, causing discomfort. Seven cases did not take medication postoperatively, and the lesions expanded with multi-organ progression. Conclusion:Patients with head and neck sarcoidosis are rare in clinical practice, and it is prone to misdiagnosis and missed diagnosis. Steroid therapy can achieve good therapeutic effects.


Asunto(s)
Cuello , Sarcoidosis , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto , Sarcoidosis/diagnóstico , Anciano , Niño , Adolescente , Cabeza , Adulto Joven , Pronóstico , Glándula Parótida/patología
14.
J Hazard Mater ; 465: 133287, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38141318

RESUMEN

Microorganisms play a critical role in the biogeochemical cycling of selenium, often reducing selenite/selenate to elemental selenium nanoparticles (SeNPs). These SeNPs typically exist in an amorphous structure but can transform into a trigonal allotrope. However, the crystal structural transition process and its impact on selenium bioavailability have not been well studied. To shed light on this, we prepared chemosynthetic and biogenic SeNPs and investigated the stability of their crystal structure. We found that biogenic SeNPs exhibited a highly stable amorphous structure in various conditions, such as lyophilization, washing, and laser irradiation, whereas chemosynthetic SeNPs transformed into a trigonal structure in the same conditions. Additionally, a core-shell structure was observed in biogenic SeNPs after electron beam irradiation. Further analysis revealed that biogenic SeNPs showed a coordination reaction between Se atoms and surface binding biomacromolecules, indicating that the outer layer of Se-biomacromolecules complex prevented the SeNPs from crystallizing. We also investigated the effects of SeNPs crystal structures on the bioavailability in bacteria, yeast, and plants, finding that the amorphous structure of SeNPs determined Se bioavailability.


Asunto(s)
Nanopartículas , Selenio , Selenio/metabolismo , Disponibilidad Biológica , Nanopartículas/química , Antioxidantes/metabolismo , Oxidación-Reducción
15.
ChemSusChem ; : e202400189, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38504639

RESUMEN

Due to the larger sizes and stronger positive polarity of Zn2+ than dominant univalent ions, Zn2+ sluggish diffusion within V2O5 host electrodes is an essential issue in developing aqueous zinc-ion batteries (ZIBs) of higher energy densities. Herein, a high-performance V2O5 cathode was developed through subtly synthesizing and tuning V2O5 with oxygen vacancies-enriched and elongated apical V=O1 bond by altering the gradient concentration of hydrazine hydrate in the gas-solid reaction system. This strategy can enhance both intrinsic and extrinsic conductivity to a large extent. The electrochemical testing demonstrated the oxygen vacancies-enriched and elongated apical V=O1 bond can not only increase the intrinsic electronic conductivity of V2O5, but also induce additional pseudocapacitance to enhance the Zn2+ diffusion kinetics. We used infrared spectroscopy and Raman spectroscopy to characterize the change in the bond length structure of V2O5. Simultaneously, the long-term cyclability (capacity retention of 76.9 % after 1200 cycles at 4.0 A g-1) and rate capabilities (218 mAh g-1 at 4.0 A g-1) are promoted as well. We believe that our work might shed light on the bond length engineering of V2O5 and provide insights for the reasonable designing of novel cathodes for practical rechargeable ZIBs.

16.
Infect Drug Resist ; 17: 229-237, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38283108

RESUMEN

Background: Maternal-fetal listeriosis, caused by Listeria monocytogenes, is a rare but serious infection. Herein, we report the clinical and genomic characteristics of a clinical L. monocytogenes ST120 isolate recovered from a pregnant woman. Methods: The clinical symptoms and treatment in pregnant woman were described in detail. Whole genome sequencing (WGS) was performed on the L. monocytogenes isolate SJZ_LM001, and the genomic characterization of the isolate was deeply analyzed. Results: The clinical symptoms in pregnant women were mainly fever, and the placenta experienced severe inflammation. The pregnant woman was treated with ampicillin for effective anti-infective therapy. Genomic analysis showed that isolate SJZ_LM001 is sequence type (ST) 120, belong to clonal complex (CC)8 and lineage II of L. monocytogenes. Additionally, the isolates SJZ_LM001 harbored a novel plasmid pSJZ_LM001, which carried arsenical resistance genes (arsACD and acr3), and cadmium resistance genes (cadAC). Drug susceptibility testing showed that the isolate SJZ-LM001 was susceptible to ampicillin, meropenem, penicillin, and cotrimoxazole. Conclusion: This is the first to identify a clinical case of infection in a pregnant woman caused by ST120 L. monocytogenes in China. These findings could benefit our understanding of the genomic characteristics of L. monocytogenes, and the pregnancy-related listeriosis and providing early diagnosis and effective targeted treatment.

17.
Adv Mater ; 36(1): e2301671, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37364981

RESUMEN

Hierarchical structure of conjugated polymers is critical to dominating their optoelectronic properties and applications. Compared to nonplanar conformational segments, coplanar conformational segments of conjugated polymers (CPs) demonstrate favorable properties for applications as a semiconductor. Herein, recent developments in the coplanar conformational structure of CPs for optoelectronic devices are summarized. First, this review comprehensively summarizes the unique properties of planar conformational structures. Second, the characteristics of the coplanar conformation in terms of optoelectrical properties and other polymer physics characteristics are emphasized. Five primary characterization methods for investigating the complanate backbone structures are illustrated, providing a systematical toolbox for studying this specific conformation. Third, internal and external conditions for inducing the coplanar conformational structure are presented, offering guidelines for designing this conformation. Fourth, the optoelectronic applications of this segment, such as light-emitting diodes, solar cells, and field-effect transistors, are briefly summarized. Finally, a conclusion and outlook for the coplanar conformational segment regarding molecular design and applications are provided.

18.
J Colloid Interface Sci ; 665: 898-910, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38564954

RESUMEN

The construction of metal-organic frameworks (MOFs) with highly efficient capture for volatile organic compounds (VOCs) adsorption under humid conditions is a significant yet formidable task. Herein, series of fluorinated UiO-67 modified with trifluoroacetic acid (TFA) and 4-fluorobenzoic acid were successfully synthesized for VOCs adsorption under high humidity conditions. Experiments results showed that UiO-67 modified with 4-fluorobenzoic acid (67-F) presented excellent adsorption capacity of 345 mg/g for toluene adsorption and exhibited great water resistance (10.0 vol% H2O, 374 mg/g toluene adsorption capacity). Characterization results indicated that the introduction of 4-fluorobenzoic acid induced the competitive coordination between 4-fluorobenzoic acid and 4,4-biphenyl dicarboxylic acid (BPDC) with Zr4+, causing the formation of abundant defects to provide extra adsorption sites. Meanwhile, the benzene ring in 4-fluorobenzoic acid enhanced the π-π conjugation, causing the further promotion of VOCs adsorption capacity. More importantly, the water resistance mechanism was investigated and elucidated that the introduction of F decreased the surface energy of 67-F and its affinity with water. Meanwhile, the metal complex induced by the fluorinated modification produced an electron-dense pore environment, which greatly improved its chemical and water stability. This work provided a strategy for preparing an adsorbent with high water resistance for real-world VOCs adsorption at high humidity conditions.

19.
Chemosphere ; 338: 139358, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37379980

RESUMEN

Efficient removal of copper complexes is a challenging issue due to their robust stability and solubility. In this study, CoFe2O4-Co0 loaded sludge-derived biochar (MSBC), a magnetic heterogeneous catalyst, was prepared to activate peroxymonosulfate (PMS) for the decomplexation and mineralization of some typical copper complexes (including Cu(Ⅱ)-EDTA, Cu(Ⅱ)-NTA, Cu(Ⅱ)-citrate, and Cu(Ⅱ)-tartrate). The results showed that abundant cobalt ferrite and cobalt nanoparticles were decorated in the plate-like carbonaceous matrix, making it a higher degree of graphitization, better conductivity and more excellent catalytic activity than the raw biochar. Cu(Ⅱ)-EDTA was chosen as the representative copper complex. Under the optimum condition, the decomplexation and mineralization efficiency of Cu(Ⅱ)-EDTA in MSBC/PMS system were 98% and 68% within 20 min, respectively. The mechanistic investigation confirmed that the activation of PMS by MSBC followed both a radical pathway contributed by SO4•- and •OH and a nonradical pathway contributed by 1O2. In addition, the electron transfer pathway between Cu(Ⅱ)-EDTA and PMS facilitated the decomplexation of Cu(Ⅱ)-EDTA. Jointly, CO, Co0, and the redox cycles of Co(Ⅲ)/Co(Ⅱ) and Fe (Ⅲ)/Fe (Ⅱ) were found to play a critical role in the decomplexation process. Overall, the MSBC/PMS system provides a new strategy for efficient decomplexation and mineralization of copper complexes.


Asunto(s)
Cobre , Aguas del Alcantarillado , Ácido Edético , Peróxidos , Fenómenos Magnéticos
20.
Chem Biol Interact ; 384: 110727, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37739050

RESUMEN

Gymnodimine-A (GYM-A) is a cyclic imine phycotoxin produced by some marine dinoflagellates. It can cause rapid death of mice via intraperitoneal administration and frequently accumulate in shellfish potentially threatening human health. In this study, four different cell lines were exposed to GYM-A for the viability assessment. Results showed that GYM-A was cytotoxic with concentration-dependent pattern to each cell type, with mean IC50 values ranging from 1.39 to 2.79 µmol L-1. Results suggested that the loss of cell viability of 4T1 and Caco-2 cells was attributed to apoptosis. Furthermore, the collapse of mitochondrial membrane potential and caspases activation were observed in the GYM-A-treated cells. Reactive oxygen species (ROS) and lipid peroxides (LPO) levels were markedly increased in 4T1 and Caco-2 cells exposed to GYM-A at 2 µmol L-1, and the oxidative stress in 4T1 cells was more obvious than that in Caco-2 cells. Additionally, unusual ultrastructure impairment on mitochondria and mitophagosomes occurred in the GYM-A-treated cells. These results suggested that an ROS-mediated mitochondrial pathway for apoptosis and mitophagy was implicated in the cytotoxic effects induced by GYM-A. This is the first report to explore the cytotoxic mechanisms of GYM-A through apoptosis and oxidative stress, and it will provide theoretical foundations for the potential therapeutic applications of GYM-A.

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