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1.
J Am Chem Soc ; 146(4): 2411-2418, 2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38234111

RESUMEN

Nanographene C222, which consists of a planar graphenic plane containing 222 carbon atoms, holds the record as the largest planar nanographene synthesized to date. However, its complete insolubility makes the processing of C222 difficult. Here we addressed this issue by introducing peripheral substituents perpendicular to the graphene plane, effectively disrupting the interlayer stacking and endowing C222 with good solubility. We also found that the electron-withdrawing substituents played a crucial role in the cyclodehydrogenation process, converting the dendritic polyphenylene precursor to C222. After disrupting the interlayer stacking, the introduction of only a few peripheral carboxylic groups allowed C222 to dissolve in phosphate buffer saline, reaching a concentration of up to 0.5 mg/mL. Taking advantage of the good photosensitizing and photothermal properties of the inner C222 core, the resulting water-soluble C222 emerged as a single-component agent for both photothermal and photodynamic tumor therapy, exhibiting an impressive tumor inhibition rate of 96%.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Terapia Fototérmica , Fotoquimioterapia/métodos , Neoplasias/tratamiento farmacológico
2.
Small ; : e2312136, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38482968

RESUMEN

The extraction of ammonia (NH3 ) through electrocatalytic nitrate reduction reaction (NO3 - RR) represents a sustainable avenue in NH3 generation and utilization. However, the catalytic efficiency of the NO3 - RR is hindered by the sluggish kinetics. This study first theoretically found that phosphide-based heterostructure can alter the adsorption structure of intermediates in the nitrate-to-ammonia process, thereby achieving precise regulation of the energy barrier in the rate-determining step. Based on theoretical design, a novel Co-doped Fe2 P@NiP2 heterojunction catalyst is successfully synthesized, which deliver a notable NH3 yield rate of 0.395 mmol h-1  cm-2 at -0.7 V versus RHE, as well as a remarkable ammonia Faraday efficiency of 97.2% at -0.6 V versus RHE. Experimental and theoretical results further confirm that redistributing electrons and shifting the center of the d-band upwards through interfacial doping modulate intermediates adsorption strength and inhibition of hydrogen evolution, leading to excellent performance in NO3 - -to-NH3 . Further integrating the Co-Fe2 P@NiP2 catalyst into a Zn-nitrate battery exhibits a substantial voltage output of 1.49 V and a commendable power density of 13.2 mW cm-2 . The heteroatom-doped heterojunction strategy provides a versatile route for developing advanced catalysts, thereby broadening the horizons of electrocatalytic methodologies for nitrate reduction and ammonia synthesis.

3.
Invest New Drugs ; 42(1): 1-13, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37971628

RESUMEN

Advances in immune checkpoint inhibitors (ICIs) have enabled more effective treatment for individuals with various types of solid tumors. Given the improved survival benefit and acceptable safety profile of ICIs in advanced gastric cancer, there is plenty of interest in the use of ICIs in the neoadjuvant setting with curative intent. Theoretically, immunoneoadjuvant with ICIs could boost the levels of endogenous tumor antigen present in the tumor to enhance T-cell priming and further enhance systemic immunity. This systemic immune response may improve the detection and elimination of the disseminated micrometastatic tumors beyond the resected tumor, which are sources of postsurgical relapse. Numerous clinical studies have begun to explore the application of ICIs in neoadjuvant treatment of gastric cancer. This article reviews the progress in the use of ICI monotherapy and in combination with alternative therapies for the treatment of gastric cancer to aid in the development of gastric cancer immunoneoadjuvant therapy and improve the overall therapeutic benefit.


Asunto(s)
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Terapia Neoadyuvante
4.
Respir Res ; 25(1): 186, 2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38678295

RESUMEN

BACKGROUND: Influenza A viruses (IAV) are extremely common respiratory viruses for the acute exacerbation of chronic obstructive pulmonary disease (AECOPD), in which IAV infection may further evoke abnormal macrophage polarization, amplify cytokine storms. Melatonin exerts potential effects of anti-inflammation and anti-IAV infection, while its effects on IAV infection-induced AECOPD are poorly understood. METHODS: COPD mice models were established through cigarette smoke exposure for consecutive 24 weeks, evaluated by the detection of lung function. AECOPD mice models were established through the intratracheal atomization of influenza A/H3N2 stocks in COPD mice, and were injected intraperitoneally with melatonin (Mel). Then, The polarization of alveolar macrophages (AMs) was assayed by flow cytometry of bronchoalveolar lavage (BAL) cells. In vitro, the effects of melatonin on macrophage polarization were analyzed in IAV-infected Cigarette smoking extract (CSE)-stimulated Raw264.7 macrophages. Moreover, the roles of the melatonin receptors (MTs) in regulating macrophage polarization and apoptosis were determined using MTs antagonist luzindole. RESULTS: The present results demonstrated that IAV/H3N2 infection deteriorated lung function (reduced FEV20,50/FVC), exacerbated lung damages in COPD mice with higher dual polarization of AMs. Melatonin therapy improved airflow limitation and lung damages of AECOPD mice by decreasing IAV nucleoprotein (IAV-NP) protein levels and the M1 polarization of pulmonary macrophages. Furthermore, in CSE-stimulated Raw264.7 cells, IAV infection further promoted the dual polarization of macrophages accompanied with decreased MT1 expression. Melatonin decreased STAT1 phosphorylation, the levels of M1 markers and IAV-NP via MTs reflected by the addition of luzindole. Recombinant IL-1ß attenuated the inhibitory effects of melatonin on IAV infection and STAT1-driven M1 polarization, while its converting enzyme inhibitor VX765 potentiated the inhibitory effects of melatonin on them. Moreover, melatonin inhibited IAV infection-induced apoptosis by suppressing IL-1ß/STAT1 signaling via MTs. CONCLUSIONS: These findings suggested that melatonin inhibited IAV infection, improved lung function and lung damages of AECOPD via suppressing IL-1ß/STAT1-driven macrophage M1 polarization and apoptosis in a MTs-dependent manner. Melatonin may be considered as a potential therapeutic agent for influenza virus infection-induced AECOPD.


Asunto(s)
Apoptosis , Subtipo H3N2 del Virus de la Influenza A , Melatonina , Enfermedad Pulmonar Obstructiva Crónica , Animales , Melatonina/farmacología , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/virología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ratones , Apoptosis/efectos de los fármacos , Células RAW 264.7 , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Infecciones por Orthomyxoviridae/tratamiento farmacológico , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/inmunología , Ratones Endogámicos C57BL , Masculino , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Progresión de la Enfermedad , Polaridad Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virología
5.
Hum Genomics ; 17(1): 64, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37454130

RESUMEN

BACKGROUND: Female breast cancer remains the second leading cause of cancer-related death in the USA. The heterogeneity in the tumor morphology across the cohort and within patients can lead to unpredictable therapy resistance, metastasis, and clinical outcome. Hence, supplementing classic pathological markers with intrinsic tumor molecular markers can help identify novel molecular subtypes and the discovery of actionable biomarkers. METHODS: We conducted a large multi-institutional genomic analysis of paired normal and tumor samples from breast cancer patients to profile the complex genomic architecture of breast tumors. Long-term patient follow-up, therapeutic regimens, and treatment response for this cohort are documented using the Breast Cancer Collaborative Registry. The majority of the patients in this study were at tumor stage 1 (51.4%) and stage 2 (36.3%) at the time of diagnosis. Whole-exome sequencing data from 554 patients were used for mutational profiling and identifying cancer drivers. RESULTS: We identified 54 tumors having at least 1000 mutations and 185 tumors with less than 100 mutations. Tumor mutational burden varied across the classified subtypes, and the top ten mutated genes include MUC4, MUC16, PIK3CA, TTN, TP53, NBPF10, NBPF1, CDC27, AHNAK2, and MUC2. Patients were classified based on seven biological and tumor-specific parameters, including grade, stage, hormone receptor status, histological subtype, Ki67 expression, lymph node status, race, and mutational profiles compared across different subtypes. Mutual exclusion of mutations in PIK3CA and TP53 was pronounced across different tumor grades. Cancer drivers specific to each subtype include TP53, PIK3CA, CDC27, CDH1, STK39, CBFB, MAP3K1, and GATA3, and mutations associated with patient survival were identified in our cohort. CONCLUSIONS: This extensive study has revealed tumor burden, driver genes, co-occurrence, mutual exclusivity, and survival effects of mutations on a US Midwestern breast cancer cohort, paving the way for developing personalized therapeutic strategies.


Asunto(s)
Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Pronóstico , Mutación , Biomarcadores de Tumor/genética , Fosfatidilinositol 3-Quinasa Clase I/genética
6.
Inorg Chem ; 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39014892

RESUMEN

Ring contraction of metallacyclobutadiene to metallacyclopropene is rare because of the increasing strain from a four-membered ring to a three-membered one. Here we demonstrate a new series of reactions of metallabenzocyclobutadiene to metallabenzocyclopropene via density functional theory calculations. The results suggest that these reactions are thermodynamically favorable ranging from -17.4 to -29.4 kcal mol-1, and a low reaction barrier (10.3 kcal mol-1) is achieved when the metal center is Ru and the ligands are one cyanide and one chloride. Further analysis suggests that a strengthened binding energy helps stabilize the transition state in the protonation process. The aromaticity during the reaction was investigated using the electron density of delocalized bonds (EDDB), isomerization stabilization energy, and isodesmic reactions. The EDDB shows that the π-conjugation is disrupted in the intermediate, and then σ-aromaticity is generated and dominant in the products. Our findings could be helpful for experimentalists in developing novel ring contraction reactions driven by aromaticity.

7.
Gastric Cancer ; 27(4): 785-801, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38782859

RESUMEN

BACKGROUND: Human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) is a heterogeneous GC subtype characterized by the overexpression of HER2. To date, few specific targeted therapies have demonstrated durable efficacy in HER2-positive GC patients, with resistance to trastuzumab typically emerging within 1 year. However, the mechanisms of resistance to trastuzumab remain incompletely understood, presenting a significant challenge to clinical practice. METHODS: In this study, we integrated genetic screening and bulk transcriptome and epigenomic profiling to define the mechanisms mediating adaptive resistance to HER2 inhibitors and identify potential effective therapeutic strategies for treating HER2-positive GCs. RESULTS: We revealed a potential association between adaptive resistance to trastuzumab in HER2-positive GC and the expression of YES-associated protein (YAP). Notably, our investigation revealed that long-term administration of trastuzumab triggers extensive chromatin remodeling and initiates YAP gene transcription in HER2-positive cells characterized by the initial inhibition and subsequent reactivation. Furthermore, treatment of HER2-positive GC cells and cell line-derived xenografts (CDX) models with YAP inhibitors in combination with trastuzumab was found to induce synergistic effects through the AKT/mTOR and ERK/mTOR pathways. CONCLUSION: These findings underscore the pivotal role of reactivated YAP and mTOR signaling pathways in the development of adaptive resistance to trastuzumab and may serve as a promising joint target to overcome resistance to trastuzumab.


Asunto(s)
Resistencia a Antineoplásicos , Proteínas Proto-Oncogénicas c-akt , Receptor ErbB-2 , Neoplasias Gástricas , Serina-Treonina Quinasas TOR , Factores de Transcripción , Trastuzumab , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Neoplasias Gástricas/genética , Trastuzumab/farmacología , Trastuzumab/uso terapéutico , Receptor ErbB-2/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Factores de Transcripción/metabolismo , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/uso terapéutico , Proteínas Señalizadoras YAP/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Transducción de Señal/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Femenino , Línea Celular Tumoral , Ratones Desnudos , Proliferación Celular
8.
Clin Chem Lab Med ; 62(5): 979-987, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37999934

RESUMEN

OBJECTIVES: To evaluate the analytical characteristics of a novel high-sensitivity cardiac troponin T (hs-cTnT) test on the automatic light-initiated chemiluminescent assay (LiCA®) system, and validated its diagnostic performance for non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: Studies included an extensive analytical evaluation and established the 99th percentile upper reference limit (URL) from apparently healthy individuals, followed by a diagnostic performance validation for NSTEMI. RESULTS: Sex-specific 99th percentile URLs were 16.0 ng/L (1.7 % CV: coefficient of variation) for men (21-92 years) and 13.4 ng/L (2.0 % CV) for women (23-87 years) in serum, and 30.6 ng/L (0.9 % CV) for men (18-87 years) and 20.2 ng/L (1.4 % CV) for women (18-88 years) in heparin plasma. Detection rates in healthy individuals ranged from 98.9 to 100 %. An excellent agreement was identified between LiCA® and Elecsys® assays with a correlation coefficient of 0.993 and mean bias of -0.7 % (-1.8-0.4 %) across the full measuring range, while the correlation coefficient and overall bias were 0.967 and -1.1 % (-2.5-0.3 %) for the lower levels of cTnT (10-100 ng/L), respectively. At the specific medical decision levels (14.0 and 52.0 ng/L), assay difference was estimated to be <5.0 %. No significant difference was found between these two assays in terms of area under curve (AUC), sensitivity and specificity, negative predictive value (NPV) and positive predictive value (PPV) for the diagnosis of NSTEMI. CONCLUSIONS: LiCA® hs-cTnT is a reliable 3rd-generation (level 4) high-sensitivity assay for detecting cardiac troponin T. The assay is acceptable for practical use in the diagnosis of NSTEMI.


Asunto(s)
Infarto del Miocardio , Infarto del Miocardio sin Elevación del ST , Infarto del Miocardio con Elevación del ST , Masculino , Humanos , Femenino , Troponina T , Infarto del Miocardio/diagnóstico , Heparina , Sensibilidad y Especificidad , Biomarcadores
9.
Molecules ; 29(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38930789

RESUMEN

The aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) plays a pivotal role in the synthesis of renewable, biodegradable plastics and sustainable chemicals. Although supported gold nanoclusters (NCs) exhibit significant potential in this process, they often suffer from low selectivity. To address this challenge, a series of gold-M (M means Ni, Fe, Cu, and Pd) bimetallic NCs catalysts were designed and synthesized to facilitate the selective oxidation of HMF to FDCA. Our findings indicate that the introduction of doped metals, particularly Ni and Pd, not only improves the reaction rates for HMF tandem oxidation but also promotes high yields of FDCA. Various characterizations techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), in situ diffuse reflectance infrared Fourier transform spectroscopy of CO adsorption (CO-DRIFTS), and temperature-programmed desorption of oxygen (O2-TPD), were employed to scrutinize the structural and electronic properties of the prepared catalysts. Notably, an electronic effect was observed across the Au-based bimetallic catalysts, facilitating the activation of reactant molecules and enhancing the catalytic performance. This study provides valuable insights into the alloy effects, aiding in the development of highly efficient Au-based bimetallic catalysts for biomass conversions.

10.
Angew Chem Int Ed Engl ; 63(2): e202315302, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38009464

RESUMEN

Nitrogen-doped cavities are pervasive in graphenic materials, and represent key sites for catalytic and electrochemical activity. However, their structures are generally heterogeneous. In this study, we present the synthesis of a well-defined molecular cutout of graphene featuring N-doped cavity. The graphitization of a macrocyclic pyridinic precursor was achieved through photochemical cyclodehydrochlorination. In comparison to its counterpart with pyridinic nitrogen at the edges, the pyridinic nitrogen atoms in this nanographene cavity exhibit significantly reduced basicity and selective binding to Ag+ ion. Analysis of the protonation and coordination equilibria revealed that the tri-N-doped cavity binds three protons, but only one Ag+ ion. These distinct protonation and coordination behaviors clearly illustrate the space confinement effect imparted by the cavities.

11.
Angew Chem Int Ed Engl ; 63(20): e202402621, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38443314

RESUMEN

The incorporation of pentagon-heptagon pairs into helical nanographenes lacks a facile synthetic route, and the impact of these pairs on chiroptical properties remains unclear. In this study, a method for the stepwise construction of pentagon-heptagon pairs in helical nanographenes by the dehydrogenation of [6]helicene units was developed. Three helical nanographenes containing pentagon-heptagon pairs were synthesized and characterized using this approach. A wide variation in the molecular geometries and photophysical properties of these helical nanographenes was observed, with changes in the helical length of these structures and the introduction of the pentagon-heptagon pairs. The embedded pentagon-heptagon pairs reduced the oxidation potential of the synthesized helical nanographenes. The high isomerization energy barriers enabled the chiral resolution of the helicene enantiomers. Chiroptical investigations revealed remarkably enhanced circularly polarized luminescence and luminescence dissymmetry factors with an increasing number of the pentagon-heptagon pairs.

12.
J Am Chem Soc ; 145(6): 3289-3293, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36745399

RESUMEN

Pentagonal cyclization at the bay positions of armchair-edged graphenic cores can build molecular bowls without the destruction of hexagonal lattices. However, this synthesis remains challenging due to unfavorable strain and the multiple reactions required. Here, we show that a new type of graphenic molecular bowl with a depth of 1.7 Å and a diameter of 1.2 nm is constructed by sextuple Se annulation at the bay positions of armchair-edged hexa-peri-hexabenzocoronene. This graphenic bowl is functionalized with phenylseleno groups that stack into a discrete bilayer dimer in solution. Such a dimer exhibits high stability and survives in the gas phase after laser ablation. Strikingly, the asymmetric one-dimensional supramolecular columns of graphenic bowl with coherent stacking configuration are observed in the solid state, which results in a strong second harmonic generation with prominent polarization dependence. Our findings present a concise synthesis of a giant molecular bowl with a graphenic core and demonstrate the unique supramolecular assembly of extended graphenic bowls.

13.
J Am Chem Soc ; 145(35): 19333-19337, 2023 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-37638550

RESUMEN

The conventional approach toward molecules with large two-photon absorption (TPA) involves donor-acceptor conjugation. Herein we show a new strategy involving the use of hexa-branched nanographenes. We synthesized two hexa-branched nanographenes, one with six benzoaceanthrylene arms fused to the coronene core and the other with six pyrenyl arms fused to the coronene core. Neither of these hexa-branched nanographenes has a donor-acceptor structure, yet they exhibited high TPA values of 3.6 × 103 and 1.9 × 104 GM, respectively, which are the highest values recorded for heteroatom-free hydrocarbon molecules. Theoretical analysis suggests that the fused branched structures are responsible for the large TPA cross-section. These findings illustrate the importance of the topology of the fused conjugated skeleton in TPA and provide an alternative structural design toward large TPA.

14.
J Am Chem Soc ; 145(5): 2815-2821, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36705468

RESUMEN

The synthesis of well-defined nanocarbon multilayers, beyond the bilayer structure, is still a challenging goal. Herein, two trilayer nanographenes were synthesized by covalently linking nanographene layers through helicene bridges. The structural characterization of the trilayer nanographenes revealed a compact trilayer-stacked architecture. The introduction of a furan ring into the helicene linker modulates the interlayer overlap and π-conjugation of the trilayer nanographenes, enabling the tuning of the interlayer coupling, as demonstrated by optical, electrochemical, and theoretical analyses. Both synthesized trilayer nanographenes are rigid chiral nanocarbons and show a chirality transfer from the helicene moiety to the stacked nanographene layers. These helical trilayer nanographenes reported here represent the covalently linked multilayer nanographenes rather than bilayer ones, showing the tunable multilayer stacking structure.

15.
J Am Chem Soc ; 145(18): 10126-10135, 2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37097709

RESUMEN

Cyclodehydrogenation reactions in the on-surface synthesis of graphene nanoribbons (GNRs) usually involve a series of Csp2-Csp2 and/or Csp2-Csp3 couplings and just happen on uncovered metal or metal oxide surfaces. It is still a big challenge to extend the growth of second-layer GNRs in the absence of necessary catalytic sites. Here, we demonstrate the direct growth of topologically nontrivial GNRs via multistep Csp2-Csp2 and Csp2-Csp3 couplings in the second layer by annealing designed bowtie-shaped precursor molecules over one monolayer on the Au(111) surface. After annealing at 700 K, most of the polymerized chains that appear in the second layer covalently link to the first-layer GNRs that have partially undergone graphitization. Following annealing at 780 K, the second-layer GNRs are formed and linked to the first-layer GNRs. Benefiting from the minimized local steric hindrance of the precursors, we suggest that the second-layer GNRs undergo domino-like cyclodehydrogenation reactions that are remotely triggered at the link. We confirm the quasi-freestanding behaviors in the second-layer GNRs by measuring the quasiparticle energy gap of topological bands and the tunable Kondo resonance from topological end spins using scanning tunneling microscopy/spectroscopy combined with first-principles calculations. Our findings pave the avenue to diverse multilayer graphene nanostructures with designer quantum spins and topological states for quantum information science.

16.
J Am Chem Soc ; 145(30): 16778-16786, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37406618

RESUMEN

Endohedral metallofullerenes (EMFs) are sub-nano carbon materials with diverse applications, yet their formation mechanism, particularly for metastable isomers, remains ambiguous. The current theoretical methods focus mainly on the most stable isomers, leading to limited predictability of metastable ones due to their low stabilities and yields. Herein, we report the successful isolation and characterization of two metastable EMFs, Sc2C2@C1(39656)-C82 and Sc2C2@C1(51383)-C84, which violate the isolated pentagon rule (IPR). These two non-IPR EMFs exhibit a rare case of planar and pennant-like Sc2C2 clusters, which can be considered hybrids of the common butterfly-shaped and linear configurations. More importantly, the theoretical results reveal that despite being metastable, these two non-IPR EMFs survived as the products from their most stable precursors, Sc2C2@C2v(5)-C80 and Sc2C2@Cs(6)-C82, via a C2 insertion during the post-formation annealing stages. We propose a systematic theoretical method for predicting metastable EMFs during the post-formation stages. The unambiguous molecular-level structural evidence, combined with the theoretical calculation results, provides valuable insights into the formation mechanisms of EMFs, shedding light on the potential of post-formation mechanisms as a promising approach for EMF synthesis.

17.
Small ; : e2306113, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38088524

RESUMEN

The interfacial electron modulation of electrocatalysts is an effective way to realize efficient hydrogen production, which is of great importance for future renewable energy systems. However, systematic theory-guided design of catalysts in heterojunction coupling is lacking. In this work, a multi-level theoretical calculation is performed to screen optimal candidates to form a heterojunction with CoP (101) surface for electrocatalytic hydrogen production. To overcome the weak adsorption of H+ on CoP (101), rational design of electrons potential well at the heterojunction interface can effectively enhance the hydrogen adsorption. All p-type cobalt-based phosphides are considered potential candidates at the beginning. After screening for conductivity, stability, interface matching screening, and ΔGH* evaluation, the CoP/Co2 P-H system is identified to be able to display optimal hydrogen production performance. To verify the theoretical design, CoP, CoP/Co2 P-H, and CoP/Co2 P-O are synthesized and the electrochemical analysis is carried out. The hydrogen evolution reaction (HER) performance is consistent with the prediction. This work utilizes the electron potential well effect and multi-level screening calculations to design highly efficient heterojunction catalysts, which can provide useful theoretical guidance for the rational design of heterojunction-type catalysts.

18.
Invest New Drugs ; 41(6): 861-869, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37864727

RESUMEN

Globally, gastrointestinal cancer is the most widespread neoplastic disease and the primary contributor to cancer-associated fatalities. Gastrointestinal signet ring cell carcinoma (SRCC) exhibits unique distinguishing features in several aspects when compared to adenocarcinomas (ACs). The scarcity of signet ring cell carcinoma has resulted in a heightened significance of related clinical and molecular investigations. However, a comprehensive and systematic review of the clinical, molecular, therapeutic, and research aspects of this disease is currently absent. This review provides an overview of the latest developments in our understanding of the clinical and molecular features of gastrointestinal signet ring cell carcinoma (SRCC). Additionally, we have compiled a list of potential therapeutic targets or biomarkers, as well as an examination of the current treatment options and the possible mechanisms of formation.


Asunto(s)
Adenocarcinoma , Carcinoma de Células en Anillo de Sello , Neoplasias Gastrointestinales , Humanos , Neoplasias Gastrointestinales/terapia , Carcinoma de Células en Anillo de Sello/diagnóstico , Carcinoma de Células en Anillo de Sello/patología , Biomarcadores
19.
Anal Biochem ; 676: 115234, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37422060

RESUMEN

Abnormal expression of carcinoembryonic antigen (CEA) can be used for early diagnosis of various cancers (e.g. colorectal cancer, cervical carcinomas, and breast cancer). In this work, using l-cysteine-ferrocene-ruthenium nanocomposites (L-Cys-Fc-Ru) to immobilize secondary antibody (Ab2) and Au nanoparticles (NPs) as the substrate to ensure accurate capture of primary antibody (Ab1), a signal-on sandwich-like biosensor was constructed in the presence of CEA. Specifically, Ru nanoassemblies (NAs) were first prepared by a facile one-step solvothermal approach as signal amplifiers for the electrical signal of Fc. Based on specific immune recognition, as the increase of CEA concentration, the content of L-Cys-Fc-Ru-Ab2 captured on the electrode surface also increased, thus the signal of Fc gradually increased. Therefore, the quantitative detection of CEA can be realized according to the peak current of Fc. After a series of experiments, it was found that the biosensor has a wide detection range from 1.0 pg mL-1 to 100.0 ng mL-1 and a low detection limit down to 0.5 pg mL-1, as well as good selectivity, repeatability and stability. Furthermore, satisfactory results were also obtained for the determination of CEA in serums, which were comparable to commercial electrochemiluminescence (ECL) method. The developed biosensor shows great potential in clinical applications.


Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama , Nanopartículas del Metal , Humanos , Femenino , Antígeno Carcinoembrionario , Oro/química , Nanopartículas del Metal/química , Inmunoensayo/métodos , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Límite de Detección
20.
Future Oncol ; 19(36): 2395-2403, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37990937

RESUMEN

At present, preoperative chemotherapy is the standard of care for the neoadjuvant treatment of potentially resectable gastric cancer (GC). However, because the efficacy and prognosis are not ideal, curative effects for this population are unsatisfactory. With the development of immune checkpoint inhibitors, the results of a few encouraging early trials of immunotherapeutic agents as neoadjuvant therapies for resectable GC have been reported. However, markers of the efficacy of immune checkpoint inhibitors remain unclear. This prospective single-center, single-arm observational study was designed to evaluate the efficacy of sintilimab plus the fluorouracil, leucovorin, oxaliplatin and docetaxel regimen as a neoadjuvant treatment for localized GC. More importantly, this work assesses multiple dimensions and include ctDNA, the immune microenvironment and intestinal microbiome to explore correlations between biomarkers and neoadjuvant therapeutic efficacy. Clinical trial registration: ChiCTR2200061629 (www.chictr.org.cn/index.aspx).


Asunto(s)
Neoplasias Gástricas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores , Docetaxel/uso terapéutico , Fluorouracilo/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Leucovorina/uso terapéutico , Terapia Neoadyuvante/métodos , Oxaliplatino/uso terapéutico , Estudios Prospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/tratamiento farmacológico , Microambiente Tumoral
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