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1.
J Comput Chem ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012324

RESUMO

The electronic structure of the strongly correlated electron system plutonium hexaboride is studied by using single-particle approximations and a many-body approach. Imaginary components of impurity Green's functions show that 5fj=5/2 and 5fj=7/2 manifolds are in conducting and insulating regimes, respectively. Quasi-particle weights and their ratio suggest that the intermediate coupling mechanism is applicable for Pu 5f electrons, and PuB6 might be in the orbital-selective localized state. The weighted summation of occupation probabilities yields the interconfiguration fluctuation and average occupation number of 5f electrons n5f ~ 5.101. The interplay of 5f-5f correlation, spin-orbit coupling, Hund's exchange interaction, many-body transition of 5f configurations, and final state effects might be responsible for the quasiparticle multiplets in electronic spectrum functions. Prominent characters in the density of state, such as the coexistence of atomic multiplet peaks in the vicinity of the Fermi level and broad Hubbard bands in the high-lying regime, suggest that PuB6 could be identified as a Racah material. Finally, the quasiparticle band structure is also presented.

2.
Mikrochim Acta ; 191(6): 297, 2024 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709347

RESUMO

A new detection platform based on a hydroxylated covalent organic framework (COF) integrated with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was constructed and used for detecting adrenergic receptor agonists (ARAs) residues in milk. The hydroxylated COF was prepared by polymerization of tris(4-aminophenyl)amine and 1,3,5-tris(4-formyl-3-hydroxyphenyl)benzene and applied to solid-phase extraction (SPE) of ARAs. This hydroxylated COF was featured with hierarchical flower-like morphology, easy preparation, and copious active adsorption sites. The adsorption model fittings and molecular simulation were applied to explore the potential adsorption mechanism. This detection platform was suitable for detecting four α2- and five ß2-ARAs residues in milk. The linear ranges of the ARAs were from 0.25 to 50 µg·kg-1; the intra-day and the inter-day repeatability were in the range 2.9-7.9% and 2.0-10.1%, respectively. This work demonstrates this hydroxylated COF has great potential as SPE cartridge packing, and provides a new way to determine ARAs residues in milk.


Assuntos
Leite , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Extração em Fase Sólida/métodos , Leite/química , Animais , Espectrometria de Massas em Tandem/métodos , Hidroxilação , Estruturas Metalorgânicas/química , Adsorção , Agonistas Adrenérgicos/química , Agonistas Adrenérgicos/análise , Limite de Detecção , Bovinos
3.
Chemosphere ; 358: 142277, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719118

RESUMO

Peracetic acid (PAA) has garnered significant attention as a novel disinfectant owing to its remarkable oxidative capacity and minimal potential to generate byproducts. In this study, we prepared a novel catalyst, denoted as cobalt modified nitrogen-doped carbon nanotubes (Co@N-CNTs), and evaluated it for PAA activation. Modification with cobalt nanoparticles (∼4.8 nm) changed the morphology and structure of the carbon nanotubes, and greatly improved their ability to activate PAA. Co@N-CNTs/PAA catalytic system shows outstanding catalytic degradation ability of antiviral drugs. Under neutral conditions, with a dosage of 0.05 g/L Co@N-CNT-9.8 and 0.25 mM PAA, the removal efficiency of acyclovir (ACV) reached 98.3% within a mere 10 min. The primary reactive species responsible for effective pollutant degradation were identified as acetylperoxyl radicals (CH3C(O)OO•) and acetyloxyl radicals (CH3C(O)O•). In addition, density functional theory (DFT) proved that Co nanoparticles, as the main catalytic sites, were more likely to adsorb PAA and transfer more electrons than N-doped graphene. This study explored the feasibility of PAA degradation of antiviral drugs in sewage, and provided new insights for the application of heterogeneous catalytic PAA in environmental remediation.


Assuntos
Antivirais , Cobalto , Nanotubos de Carbono , Nitrogênio , Ácido Peracético , Nanotubos de Carbono/química , Nitrogênio/química , Cobalto/química , Ácido Peracético/química , Catálise , Antivirais/química , Poluentes Químicos da Água/química , Aciclovir/química , Adsorção
4.
Am J Surg Pathol ; 48(7): 874-882, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38501656

RESUMO

ABSTRACT: Renal hemangioblastoma (HB) is a rare subset of HBs arising outside of the central nervous system (CNS), with its molecular drivers remaining entirely unknown. There were no significant alterations detected in previous studies, including von Hippel-Lindau gene alterations, which are commonly associated with CNS-HB. This study aimed to determine the real molecular identity of renal HB and better understand its relationship with CNS-HB. A cohort of 10 renal HBs was submitted for next-generation sequencing technology. As a control, 5 classic CNS-HBs were similarly analyzed. Based on the molecular results, glycoprotein nonmetastatic B (GPNMB) immunohistochemistry was further performed in the cases of renal HB and CNS-HB. Mutational analysis demonstrated that all 10 renal HBs harbored somatic mutations in tuberous sclerosis complex 1 ( TSC1 , 5 cases), TSC2 (3 cases), and mammalian target of rapamycin (2 cases), with the majority classified as pathogenic or likely pathogenic. The CNS-HB cohort uniformly demonstrated somatic mutations in the von Hippel-Lindau gene. GPNMB was strong and diffuse in all 10 renal HBs and completely negative in CNS-HBs, reinforcing the molecular findings. Our study reveals a specific molecular hallmark in renal HB, characterized by recurrent TSC/mammalian target of rapamycin mutations, which defines it as a unique entity distinct from CNS-HB. This molecular finding potentially expands the therapeutic options for patients with renal HB. GPNMB can be considered for inclusion in immunohistochemical panels to improve renal HB identification.


Assuntos
Hemangioblastoma , Neoplasias Renais , Mutação , Serina-Treonina Quinases TOR , Proteína 2 do Complexo Esclerose Tuberosa , Humanos , Hemangioblastoma/genética , Hemangioblastoma/patologia , Hemangioblastoma/química , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/química , Feminino , Masculino , Proteína 2 do Complexo Esclerose Tuberosa/genética , Adulto , Pessoa de Meia-Idade , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Análise Mutacional de DNA , Esclerose Tuberosa/genética , Esclerose Tuberosa/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Neoplasias do Sistema Nervoso Central/genética , Neoplasias do Sistema Nervoso Central/patologia , Neoplasias do Sistema Nervoso Central/química , Imuno-Histoquímica , Proteína 1 do Complexo Esclerose Tuberosa/genética , Idoso , Predisposição Genética para Doença , Adolescente , Fenótipo , Adulto Jovem , Criança , Sequenciamento de Nucleotídeos em Larga Escala
5.
Food Chem ; 447: 138867, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38447237

RESUMO

Fluoroquinolones (FQs) are a category of broadly used antibiotics. Development of an effective and sensitive approach for determination of trace FQs in environmental and food samples is still challenging. Herein, the hydroxyl-containing triazine-based conjugated microporous polymers (CMPs-OH) was constructed and served as SPE absorbent for the efficient enrichment of FQs. Based on DFT simulations, the excellent enrichment capacity between CMPs-OH and FQs was contributed by hydrogen bonding and π-π interactions. In combination with high-performance liquid chromatography-tandem mass spectrometry, the proposed approach exhibited a wide linear range (0.2-400 ng L-1), low detection limits (0.05-0.15 ng L-1), and good intraday and interday precisions under optimal conditions. In addition, the established method was effectively utilized for the determination of FQs in fourteen samples with recoveries between 82.6 % and 109.2 %. This work provided a feasible sample pretreatment method for monitoring FQs in environmental and food matrices.


Assuntos
Polímeros , Poluentes Químicos da Água , Polímeros/química , Poluentes Químicos da Água/análise , Fluoroquinolonas/análise , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida/métodos
6.
J Hazard Mater ; 465: 133468, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38219584

RESUMO

Microporous organic networks (MONs) are highly porous materials that are particularly useful in analytical chemistry. However, the use of these materials is often limited by the functional groups available on their surface. Here, we described the polymerization of a sea urchin-like structure material at ambient temperature, that was functionalized with hydroxyl, carboxyl, and triazine groups and denoted as OH-COOH-MON-TEPT. A substantial proportion of OH-COOH-MON-TEPT was intricately decorated EDA-Fe3O4, creating a well-designed configuration (EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC) for superior adsorption of the target analytes phenylurea herbicides (PUHs) via magnetic solid-phase extraction (MSPE). The proposed method showed remarkably low limits of detection ranging from 0.03 to 0.22 ng·L-1. Experimental investigations and theoretical analyses unveiled the adsorption mode between EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC and PUHs. These findings establish a robust foundation for potential applications of EDA-Fe3O4 @OH-COOH-MON-TEPT-EDC in the analysis of various polar contaminants.

7.
Food Chem ; 441: 138267, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38159435

RESUMO

A novel cationic metal-organic framework (iMOF-Ni) was designed and synthesized by a solvothermal method. It was fabricated as a solid-phase extraction (SPE) cartridge and exhibited high adsorption performance for Bisphenols (BPs). The theoretical simulation demonstrated that the adsorption mechanism between iMOF-Ni and BPs was attributed to cation-π bonding, π-π interaction, and electrostatic interactions. Under optimized SPE, a method for analyzing BPs was established by combining high-performance liquid chromatography-diode array detection (HPLC-DAD). The developed method has good linearity (R2 ≥ 0.994), low detection limits (0.07-0.16 ng/mL), and good reproducibility (1.72-6.35 %, n = 6). The applicability of the method was further evaluated by analyzing water and milk samples. Recoveries of four BPs in spiked samples were from 72.2 % to 96.6 %.


Assuntos
Compostos Benzidrílicos , Estruturas Metalorgânicas , Leite , Fenóis , Animais , Água , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
8.
Artigo em Inglês | MEDLINE | ID: mdl-37909321

RESUMO

The development of the valid strategy to enhance laser desorption/ionization efficiency gives rise to widespread concern in surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) technology. Herein, a hybrid of Au NP-decorated graphdiyne (Au/GDY) was fabricated and employed as the SALDI-MS matrix for the first time, and a mechanism based on photothermal and photochemical energy conversions was proposed to understand LDI processes. Given theoretical simulations and microstructure characterizations, it was revealed that the formation of a coupled thermal field and internal electric field endow the as-prepared Au/GDY matrix with superior desorption and ionization efficiency, respectively. Moreover, laser-induced matrix ablation introduced strain and defect level into the Au/GDY hybrid, suppressing the recombination of charge carriers and thereby facilitating analyte ionization. The optimized Au/GDY matrix allowed for reliable detection of trace sulfacetamide and visualization of exogenous/endogenous components in biological tissues. This work offers an integrated solution to promote LDI efficiency based on collaborative photothermal conversion and internal electric field, and may inspire the design of novel semiconductor-based surface matrices.

9.
Phys Chem Chem Phys ; 25(44): 30391-30404, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909910

RESUMO

First-principles calculations were performed on a plutonium and americium mixed oxide (PuAmO4), aiming at revealing the effects of electron correlation, Pu/Am 5f-conduction electrons' hybridization, and relativity on its electronic properties. The many-body calculation suggests that the spin-orbit-coupling (SOC)-splitting of j = 5/2 and j = 7/2 manifolds are both in the weakly and moderately correlated states, respectively, implying that the jj coupling scheme is more appropriate for Pu/Am 5f electrons. The density of states, 5f occupation numbers, and Green's functions all suggest that both Pu and Am 5f electrons exhibit the coexistence of the localized and delocalized states. The admixture of 5fn atomic configurations, Pu/Am 5f-conduction electrons' hybridization, and dual characteristics of 5f electrons yield average occupation numbers of 5f electrons n5f = 4.78 and 5.86 for Pu and Am ions, respectively. Within the DFT+DMFT calculation, the weighted-summation-derived occupation numbers in terms of 5f4/5f5/5f6 and 5f5/5f6 configurations for Pu and Am 5f electrons, respectively, are in reasonable agreement with those of other DFT-based calculations.

10.
Medicine (Baltimore) ; 102(34): e34860, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37653838

RESUMO

The incidence and mortality of colon cancer are increasing, and effective biomarkers for its diagnosis are limited. 5-methylcytosine (5mC), a vital DNA methylation marker, plays important roles in gene expression, genomic imprinting, and transposon inhibition. This study aimed to identify the predictors of colon cancer prognosis and lay the foundation for research on therapeutic targets by detecting the levels of 5mC, 5-hydroxymethylcytosine (5hmC), 5-formyl cytosine (5fC), and 5-carboxylcytosine (5caC) in colon cancer and adjacent non-tumor tissues. A tissue microarray including 100 colon cancer tissue samples and 60 adjacent non-tumor tissue samples was used. The expression levels of 5mC and its ramifications were assessed by immunohistochemistry. According to the expression levels, patients were divided into moderately positive and strongly positive groups, and the correlation between clinicopathological characteristics and methylation marks was assessed using 2-sided chi-square tests. The prognostic values of 5mC, 5hmC, 5fC, and 5caC were tested using Kaplan-Meier analyses. Compared with adjacent non-tumor tissues, the overall levels of DNA methylation were lower in colon carcinoma lesions. However, the clinical parameters were not significantly associated with these methylation markers, except for 5hmC, which was associated with the age of cancer patients (P value = .043). Kaplan-Meier analysis disclosed that moderate positive group had a significantly shorter disease specific survival than strong positive group for patients with different levels of 5mC (65.2 vs 95.2 months, P = .014) and 5hmC (71.2 vs 97.5 months, P = .045). 5mC and its ramifications (5hmC, 5fC, and 5caC) can serve as biomarkers for colon cancer. 5mC and 5hmC are stable predictors and therapeutic targets in colon cancer. However, further understanding of its function will help to reveal the complex tumorigenic process and identify new therapeutic strategies.


Assuntos
5-Metilcitosina , Neoplasias do Colo , Humanos , Prognóstico , Metilação de DNA
11.
ESC Heart Fail ; 10(6): 3237-3249, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37705352

RESUMO

Acute kidney injury (AKI) is common in patients with heart failure (HF), but studies have been inconsistent about the incidence of AKI in patients with HF. We conducted a meta-analysis to examine the incidence of AKI and its impact on mortality in patients with HF. We also looked at inpatient variables that could predict the development of AKI to identify potential risk factors, so that these can be used as a starting point for intervention and prevention in this group. The Embase, Medline, PubMed, Cochrane libraries, and Web of Science databases were used for searching articles from the inception of the database to October 2022. The EndNote software was used for screening. Meta-analysis was performed using Stata 16.0 software to combine effect sizes. A total of 37 studies were included. Of all the 3 533 583 patients with HF, 774 887 had AKI, with a pooled incidence of 33% [95% confidence interval (CI): 32-35%]. The incidence rate of AKI in acute HF and chronic HF was 36% (95% CI: 31-40%) and 30% (95% CI: 24-35%), respectively. Eleven studies found that AKI patients had higher in-hospital mortality than non-AKI patients [risk ratio (RR): 3.65; 95% CI: 3.04-4.39, P < 0.001]. Mortality was assessed in five studies, and it was found that mortality remained high at 1-year follow-up after onset of AKI (RR: 1.85, 95% CI: 1.54-2.22, P < 0.001). Fifteen admission variables were included and analysed in 13 studies. The combined results showed that diabetes, hypertension, history of chronic kidney disease, chronic HF systolic, age, N-terminal pro-B-type natriuretic peptide, creatinine > 1.0 mg/dL, index estimated glomerular filtration rate < 60 mL/min/1.73 m2 , blood urea nitrogen > 24 mg/dL, intravenous dobutamine, and serum albumin were predictor factors for HF patients with AKI (P < 0.05). In this meta-analysis, AKI occurred in approximately 33% of HF patients during hospitalization and the risk of dying in the hospital was tripled. Even during 1-year long-term follow-up, the risk of death remained high, and multiple inpatient variables showed that HF patients tended to have AKI. Early intervention and treatment are important to reduce the incidence of AKI and improve the prognosis.


Assuntos
Injúria Renal Aguda , Insuficiência Cardíaca , Humanos , Incidência , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/epidemiologia , Prognóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Fatores de Risco
12.
J Hazard Mater ; 459: 132336, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37597390

RESUMO

Bisphenol A (BPA) displays harmful effects on the human health, including potent endocrine activity and potential impact on the development of cancer. Analysis BPA residues in water and plastic products attracted considerable attention in the past decades. However, dominantly used conventional analysis techniques are unable to directly and non-destructively identify the correct species of BPA in plastic products. Hence, this study demonstrates the effective utilisation of boron nitride quantum dots (BNQDs) as an inorganic matrix in matrix-assisted laser desorption/ionization mass spectrometry analysis and imaging (MALDI-MS & MSI) for BPA. The presence of abundant hydroxyl and amino groups on the BNQDs' surface is favourable for the formation of hydrogen bonds with BPA, and increases their ionization and chemoselectivity. Intriguingly, the BNQDs matrix offers a distinct signal for phenolic hazardous molecules featuring different hydroxyl groups. The method was applied to detect BPA at nanomolar level in environmental water, and also allowed non-destructive and in situ mapping of BPA in plastics and pacifiers. This research provides a novel strategy for adapting nanomaterials as inorganic matrices for analysis of small molecular pollutants in environmentally relevant samples using MALDI-MS & MSI.

13.
Histopathology ; 83(5): 798-809, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37565303

RESUMO

AIMS: Metaplastic thymoma is a rare thymic tumour characterized by Yes Associated Protein 1 (YAP1) and Mastermind Like Transcriptional Coactivator 2 (MAML2) gene fusions resulting from an intrachromosomal inversion of chromosome 11. Immunohistochemistry with an antibody directed against the C-terminus of YAP1 has shown loss of expression in YAP1-rearranged vascular neoplasms, poromas, and porocarcinomas. This study aimed to validate an anti-YAP1 C-terminal antibody as an ancillary immunohistochemical marker for the diagnosis of metaplastic thymoma. MATERIALS AND METHODS: Ten metaplastic thymomas were selected for the current study. Fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and reverse transcription-polymerase chain reaction (RT-PCR) analyses were performed to detect YAP1::MAML2 fusions. We then performed immunohistochemistry to detect YAP1 C-terminus expression in 10 metaplastic thymomas, 50 conventional thymomas (10 each of type A thymoma, type AB thymoma, type B1 thymoma, type B2 thymoma, and type B3 thymoma) and seven thymic carcinomas. RESULTS: All 10 cases showed narrow split signals with a distance of nearly two signal diameters and sometimes had false-negative results in YAP1 and MAML2 break-apart FISH (BA-FISH). Abnormal colocalized signals of the YAP1::MAML2 fusion were observed in all 10 cases using fusion FISH (F-FISH) assays. Eight of 10 cases with adequate nucleic acids were successfully sequenced and all showed YAP1::MAML2 fusions; in two cases the fusions were detected by both DNA and RNA sequencing and in six cases by RNA sequencing only. YAP1::MAML2 fusion transcripts were identified in four cases by RT-PCR. Metaplastic thymoma showed loss of YAP1 C-terminus expression in all 10 (100%) cases. All other thymic neoplasms showed retained YAP1 C-terminus expression. CONCLUSION: YAP1 C-terminus immunohistochemistry is a highly sensitive and specific ancillary marker that distinguishes metaplastic thymoma from its mimics. BA-FISH assays could not effectively detect YAP1::MAML2 fusions due to the proximity of the two genes. Loss of YAP1 C-terminus expression is a reliable surrogate for the detection of YAP1::MAML2 fusions in metaplastic thymoma.


Assuntos
Timoma , Neoplasias do Timo , Humanos , Timoma/diagnóstico , Timoma/genética , Timoma/metabolismo , Hibridização in Situ Fluorescente , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias do Timo/diagnóstico , Neoplasias do Timo/genética , Neoplasias do Timo/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Rearranjo Gênico , Transativadores/genética
14.
Chemphyschem ; 24(18): e202300242, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37369624

RESUMO

The electronic properties, in particular, the occupation number of 5f electrons and the valence state of U ions in uranium sesquinitride (U2 N3 ) are studied by using density functional theory (DFT) calculations merged with dynamical mean-field theory (DMFT). The results demonstrate that j=5/2 and j=7/2 manifolds are in the weakly correlated metallic and weakly correlated insulating regimes, respectively. The quasi-particle weights indicate that LS coupling scheme is more feasible for 5f electrons, which are not in the orbital-selective localized state. The weighted summation of the occupation probabilities of 5fn (n=0,1,2,3,4) atomic configurations suggests that 5f electrons have the inter-configuration fluctuation, or the mixed-valence state for U ions, together with an average occupation number of 5f electrons n5f ∼2.234, which is in good agreement with the electron localization function (ELF) and occupation analysis based on other DFT-based calculations. The 5fn -mixing-driven inter-configuration fluctuation might originate from the dual nature of 5f electrons, and the flexible electronic configuration of U ions. Finally, the so-called quasiparticle band structure is also discussed.

15.
Food Chem ; 418: 135935, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36944310

RESUMO

Gold nanoparticles (AuNPs) represent an attractive inorganic matrix for laser desorption/ionization mass spectrometry (LDI-MS) detection of low-molecular-weight analytes; however, their direct use is hindered by severe aggregation. To limit AuNPs aggregation, hexagonal boron nitride nanosheets (h-BNNs) were employed as supports to improve their desorption/ionization efficiency. Thus, Au@BN was synthesized and systematically characterized. It showed low background noise and high sensitivity for LDI-MS of fipronil and its metabolites. Au@BN-assisted LDI-MS was validated using complex samples including blueberry juice, green tea beverage, and fish muscle, achieving low detection limits (0.05-0.20 µg·L-1 for liquid media, 0.82-1.25 ng·g-1 for fish muscle), wide linear ranges (0.2-100 µg·L-1 for liquid media, 3.00-1000 ng·g-1 for fish muscle), high reproducibility (7.55%-13.7%), and satisfactory recoveries (82.62%-109.1%). Furthermore, spatial distributions of analytes in strawberries and zebrafish were successfully imaged. This strategy allows for the quantitative analysis of other small molecules in complex substrates.


Assuntos
Ouro , Nanopartículas Metálicas , Animais , Ouro/química , Lasers , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Peixe-Zebra , Análise de Alimentos
16.
Anal Chim Acta ; 1239: 340662, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36628702

RESUMO

It is challenging to achieve the highly sensitive detection of glucocorticoids at ultratrace levels because of the abundant hydrophilic groups in their molecules and the complexity of environmental water sample matrices. Here, a highly crystalline three-dimensional hydroxylated covalent organic frameworks (denoted by COF-301) with tetra(4-anilyl)methane (TAM) and 2,5-dihydroxyterephthalaldehyde (DHTA) as building units was constructed and proposed as adsorbent for solid phase extraction (SPE) of glucocorticoids. Theoretical studies were conducted to elucidate the potential adsorption mechanism of glucocorticoids on the COF-301. The COF-301 based SPE combined with liquid chromatography-tandem mass spectrometry provides a promising approach for the preconcentration and determination of glucocorticoids residue in water samples. Good linearity with a correlation coefficient exceeding 0.9988, low limits of detection ranging from 0.024 to 0.075 ng L-1 and relative standard deviations below 6.68% were achieved. The proposed method was successfully applied to analyze glucocorticoids residue in actual water samples, demonstrating the prospects of this method for the determination of trace glucocorticoids.


Assuntos
Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Glucocorticoides/análise , Cromatografia Líquida , Extração em Fase Sólida/métodos , Água/química , Cromatografia Líquida de Alta Pressão , Limite de Detecção
17.
Colloids Surf A Physicochem Eng Asp ; 656: 130393, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36277261

RESUMO

The consumption of famciclovir (FCV) has been increased dramatically since the outbreak of coronavirus in 2019, and the pollution and harm of FCV in waters are concerned. Here, by utilizing aryl halides on 2, 4, 6-tris(4-bromophenyl)- 1, 3, 5-triazine (BPT) and primary amine groups on benzidine (BZ), a novel conjugated microporous polymer, namely BPT-BZ-CMP, was synthesized by Buchwald-Hartwig coupling reaction and applied in the removal of FCV from aqueous solution firstly. The synthesized BPT-BZ-CMP were characterized by various methods, including FTIR, SEM, BET, and Zeta-potential. Due to the micropore structure and high specific surface area, it took only 30 min for BPT-BZ-CMP to adsorb FCV to reach an equilibrium, and the maximum adsorption capacity was 347.8 mg·g-1. The Liu and pseudo-second-order kinetic models properly fit the adsorption equilibrium and kinetic data, respectively. The adsorption process was a spontaneous process, and the hydrogen bonding, π-π interaction and C-H···π interaction enhanced the adsorption of FCV on BPT-BZ-CMP. BPT-BZ-CMP maintained a good adsorption capacity after four consecutive adsorption-desorption cycle experiments. This study confirmed the potential of BPT-BZ-CMP as efficient sorbent to remove FCV from aqueous solutions.

18.
Sep Purif Technol ; 305: 122517, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36340050

RESUMO

Chloroquine phosphate (CQP) has been suggested as an important and effective clinical reliever medication for the 2019 coronavirus (COVID-19). Nevertheless, its excessive use will inevitably cause irreparable damage to the entire ecosystem, thereby posing a considerable environmental safety concern. Hence, the development of highly-efficient methods of removing CQP from water pollution sources, e.g., effluents from hospitals and pharmaceutical factories is significant. This study reported the fabrication of novel C-N bond linked conjugated microporous polymers (CMPs) (BPT-DMB-CMP) with multiple nitrogen-rich anchoring sites for the quick and efficient removal of CQP from aqueous solutions. The irreversible covalent C-N bond linked in the internal framework of BPT-DMB-CMP endowed it with good chemical stability and excellent adsorbent regeneration. With its predesigned functional groups (i.e., rich N-H bonds, triazine rings, and benzene rings) and large area surface (1,019.89 m2·g-1), BPT-DMB-CMP demonstrated rapid adsorption kinetics (25 min) and an extraordinary adsorption capacity (334.70 mg·g-1) for CQP, which is relatively higher than that of other adsorbents. The adsorption behavior of CQP on BPT-DMB-CMP corresponded with Liu model and mixed-order model. Based on the density functional theory (DFT) calculations, X-ray photoelectron spectroscopy (XPS), and adsorption comparisons test, the halogen bonding, and hydrogen bonding cooperates with π - π, C - H···π interactions and size-matching effect in the CQP adsorption system on BPT-DMB-CMP. The excellent practicability for the removal of CQP from real wastewater samples verified the prospect of practical application of BPT-DMB-CMP. BPT-DMB-CMP exhibited the application potentials for the adsorption of other antiviral drugs. This work opens up an efficient, simple, and high adsorption capacity way for removal CQP.

19.
Food Chem ; 404(Pt B): 134681, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36327505

RESUMO

This study synthesized a conjugated microporous polymer (CMP) at room temperature, which has high surface area, large conjugate system, and nitrogen-rich features. The material was explored as a solid-phase extraction (SPE) column, and it showed a higher extraction efficiency for nitro-musks compared to most commercial columns. Under optimal SPE conditions, a sensitive and efficient method for determining five nitro-musks was established based on gas chromatography-mass spectrometry (GC-MS). The method showed excellent linearity (R2 ≥ 0.996), low limits of detection (0.13-0.57 ng·L-1), good repeatability (1.1-4.0 %, n = 6) and was applied to the detection of trace nitro-musks in water and milk samples. The mechanism was further discussed combined with a simulation calculation. The advantages of the proposed method were mainly reflected in the extraction efficiency and sensitivity, which also indicated the potential of CMPs as a sample pretreatment material.


Assuntos
Nitrogênio , Polímeros , Polímeros/química , Temperatura , Extração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos
20.
Chinese Journal of Pathology ; (12): 1237-1243, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1012399

RESUMO

Objective: To investigate the clinicopathological features, and molecular genetic alterations of metaplastic thymoma (MT). Methods: A total of ten MT cases, diagnosed from 2011 to 2021, were selected from the Department of Pathology of Jinling Hospital, Nanjing University Medical School, Nanjing, China for clinicopathological and immunohistochemical (IHC) examination and clinical follow-up. Fluorescence in situ hybridization (FISH), next-generation sequencing (NGS), and YAP1 C-terminus (YAP1-CT) IHC were performed to detect YAP1::MAML2 fusions. Results: There were four males and six females, ranging in age from 29 to 60 years (mean 50 years, median 54 years). Microscopically, all tumors showed a typical biphasic morphology consisting of epithelial components and gradually or abruptly transitioning spindle cell components. The two components were present in varying proportions in different cases. Immunophenotypically, the epithelial cells were diffusely positive for CKpan, CK5/6 and p63. The spindle cells were diffusely positive for vimentin and focally positive for EMA. TdT was negative in the background lymphocytes. Ki-67 proliferation index was less than 5%. YAP1 and MAML2 break-apart FISH analyses showed that all ten cases had narrow split signals with a distance of nearly 2 signal diameters and may be considered false-negative. Using YAP1::MAML2 fusion FISH assays, abnormal fusion signals were observed in all the ten cases. NGS demonstrated YAP1::MAML2 fusions in all eight cases with adequate nucleic acids; in two cases the fusions were detected by DNA sequencing and in eight cases by RNA sequencing. All ten cases of MT demonstrated loss of YAP1 C-terminal expression in epithelioid cells. Conclusions: MT is a rare and low-grade thymic tumor characterized by a biphasic pattern and YAP1::MAML2 fusions. Break-apart FISH assays may sometimes show false-negative results due to the proximity of YAP1 and MAML2, while YAP1 C-terminal IHC is a highly sensitive and specific marker for MT. Loss of YAP1 C-terminal expression can also be used to screen YAP1::MAML2 fusions for possible MT cases.


Assuntos
Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Timoma/genética , Hibridização in Situ Fluorescente , Fatores de Transcrição/genética , Mutação , Neoplasias do Timo/genética
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