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1.
BMC Public Health ; 24(1): 2124, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107746

RESUMEN

BACKGROUND: The increasing prevalence of allergies and asthma has led to a growing global socioeconomic burden. Since the outbreak of the COVID-19 pandemic, the health and lifestyles of children and adolescents have changed dramatically. It's unclear how this shift impacted allergy and asthma, with limited studies addressing this question. We aim to explore the difference of the prevalence of allergies and asthma among US children and adolescents during and before the COVID-19 pandemic using a nationally representative sample of US children and adolescents. METHODS: This cross-sectional study included 31,503 participants in the National Health Interview Survey (NHIS) between 2018 and 2021. Allergies and asthma were defined on an affirmative response in the questionnaire by a parent or guardian. Chi-square tests were used to compare baseline characteristics with allergies and asthma for categorical variables. Differences in prevalence during and before the COVID-19 pandemic were estimated with weighted logistic regression, adjusting for demographic factors. Interaction analyses explored variations across strata. RESULTS: In US children and adolescents aged 0 to 17, prevalence of any allergy was 26.1% (95% CI, 24.8%- 27.4%) in 2018 and 27.1% (95% CI, 25.9%- 28.2%) in 2021. Thereinto, in 2018, prevalence of respiratory allergies, food allergies and skin allergies were 14.0% (95% CI, 13.1%- 15.0%), 6.5% (95% CI, 5.8%- 7.1%) and 12.6% (95% CI, 11.6%- 13.5%), respectively, and in 2021, 18.8% (95% CI, 17.8%- 19.9%), 5.8% (95% CI, 5.2%- 6.4%) and 10.7% (95% CI, 9.9%- 11.5%), respectively. And prevalence of asthma was 11.1% (95% CI, 10.5%- 11.7%) in 2018-2019 and 9.8% (95% CI, 9.2%- 10.4%) in 2020-2021. Prevalence of respiratory allergies, skin allergies and asthma during and before the COVID-19 pandemic in children and adolescents had statistically significant differences. The differences persisted after adjusting for demographic and socioeconomic variables. CONCLUSION: Prevalence of respiratory allergies increased and the prevalence of both skin allergies and asthma decreased among US children and adolescents during the COVID-19 pandemic compared with the pre-COVID-19 pandemic. Further research is required to explore the association between allergic diseases and the pandemic, with a particular emphasis on the impact of lifestyle changes resulting from measures to prevent COVID-19 infection.


Asunto(s)
Asma , COVID-19 , Hipersensibilidad , Humanos , COVID-19/epidemiología , Adolescente , Asma/epidemiología , Niño , Prevalencia , Estados Unidos/epidemiología , Masculino , Femenino , Estudios Transversales , Hipersensibilidad/epidemiología , Preescolar , Lactante , Recién Nacido , Pandemias , Encuestas Epidemiológicas , SARS-CoV-2
2.
J Stroke Cerebrovasc Dis ; 33(8): 107752, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38701939

RESUMEN

BACKGROUND: Observational studies have suggested a potential association between abdominal viscera volume and increased risk of stroke. However, the causal relationship remains unclear. This study aims to utilize Mendelian randomization (MR) to explore the genetic causal relationship between them. METHODS: We conducted MR analysis to study the causal effects of five abdominal viscera volumes on stroke. The genetic variations of abdominal viscera volume were obtained from the UK Biobank, and the summary data for stroke and ischemic stroke were acquired from the MEGASTROKE consortium. This study employed inverse variance weighting (IVW), MR Egger, and weighted median methods. IVW served as the primary MR analysis method, supplemented by other sensitivity analyses to validate the robustness of the results. RESULTS: We found that liver volume can causally increase the risk of stroke [odds ratio (OR): 1.13, 95 % confidence interval (CI): 1.03-1.25, P = 0.013] and ischemic stroke (OR: 1.14, 95 % CI: 1.03-1.26, P = 0.012). No causal relationships between other abdominal viscera volumes and stroke and ischemic stroke appeared to be present (P > 0.05). Sensitivity analyses confirmed the robustness of the results. CONCLUSION: Our research findings indicate a causal relationship between liver volume and stroke, highlighting the potential role of liver volume in the onset of stroke. However, further basic and clinical research is needed to delve into the specific mechanisms underlying the relationship between liver volume and stroke, and to implement interventions aimed at reducing the impact of liver volume on stroke risk.


Asunto(s)
Predisposición Genética a la Enfermedad , Accidente Cerebrovascular Isquémico , Hígado , Análisis de la Aleatorización Mendeliana , Humanos , Hígado/patología , Factores de Riesgo , Tamaño de los Órganos , Medición de Riesgo , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/epidemiología , Accidente Cerebrovascular Isquémico/etiología , Fenotipo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Masculino , Femenino , Polimorfismo de Nucleótido Simple , Persona de Mediana Edad
3.
Molecules ; 29(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38338381

RESUMEN

Water pollution has becoming an increasingly serious issue, and it has attracted a significant amount of attention from scholars. Here, in order remove heavy metal hexavalent chromium (Cr (VI)) from wastewater, graphitic carbon nitride (g-C3N4) was modified with molybdenum disulfide (MoS2) at different mass ratios via an ultrasonic method to synthesize g-C3N4/MoS2 (CNM) nanocomposites as photocatalysts. The nanocomposites displayed efficient photocatalytic removal of toxic hexavalent chromium (Cr (VI)) from water under UV, solar, and visible light irradiation. The CNM composite with a 1:2 g-C3N4 to MoS2 ratio achieved optimal 91% Cr (VI) removal efficiency at an initial 20 mg/L Cr (VI) concentration and pH 3 after 120 min visible light irradiation. The results showed a high pH range and good recycling stability. The g-C3N4/MoS2 nanocomposites exhibited higher performance compared to pure g-C3N4 due to the narrowed band gap of the Z-scheme heterojunction structure and effective separation of photo-generated electron-hole pairs, as evidenced by structural and optical characterization. Overall, the ultrasonic synthesis of g-C3N4/MoS2 photocatalysts shows promise as an efficient technique for enhancing heavy metal wastewater remediation under solar and visible light.

4.
Molecules ; 29(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38792262

RESUMEN

Chebulae Fructus (CF) is known as one of the richest sources of hydrolyzable tannins (HTs). In this study, ultra-performance liquid chromatography coupled with a photodiode array detector method was established for simultaneous determination of the 12 common phenolcarboxylic and tannic constituents (PTCs). Using this method, quantitative analysis was accomplished in CF and other four adulterants, including Terminaliae Belliricae Fructus, Phyllanthi Fructus, Chebulae Fructus Immaturus, and Canarii Fructus. Based on a quantitative analysis of the focused compounds, discrimination of CF and other four adulterants was successfully accomplished by hierarchical cluster analysis and principal component analysis. Additionally, the total contents of the 12 compounds that we focused on in this study were unveiled as 148.86 mg/g, 96.14 mg/g, and 18.64 mg/g in exocarp, mesocarp, and endocarp and seed of CF, respectively, and PTCs were witnessed to be the most abundant in the exocarp of CF. Noticeably, the HTs (chebulagic acid, chebulanin acid, chebulinic acid, and punicalagin) were observed to be ultimately degraded to chebulic acid, gallic acid, and ellagic acid during sunlight-drying of the fresh fruits. As a result, our study indicated that CF and its adulterants could be distinguished by the observed 12 PTCs, which were mainly distributed in the exocarp of the fruits. The HTs were prone to degrade into the three simple phenolcarboxylic acids during drying or processing, allowing us to obtain a more comprehensive understanding of the PTCs, with great significance in the improved quality of CF and related products.


Asunto(s)
Frutas , Taninos Hidrolizables , Taninos Hidrolizables/química , Taninos Hidrolizables/análisis , Frutas/química , Cromatografía Líquida de Alta Presión , Terminalia/química , Taninos/análisis , Taninos/química , Extractos Vegetales/química , Extractos Vegetales/análisis
5.
Angew Chem Int Ed Engl ; : e202411217, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103975

RESUMEN

Hole-transporting materials (HTMs) are crucial for obtaining the stability and high efficiency of perovskite solar cells (PSCs). However, the current state-of-the-art n-i-p PSCs relied on the use of 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) exhibit inferior intrinsic and ambient stability due to the p-dopant and hydrophilic Li-TFSI additive. In this study, a new spiro-type HTM with a critical quasi-planar core (Z-W-03) is developed to improve both the thermal and ambient stability of PSCs. The results suggest that the planar carbazole structure effectively passivates the trap states compared to the triphenylamine with a propeller-like conformation in spiro-OMeTAD. This passivation effect leads to the shallower trap states when the quasi-planar HTMs interact with the Pb-dimer. Consequently, the device using Z-W-03 achieves a higher Voc of 1.178 V compared to the spiro-OMeTAD's 1.155 V, resulting in an enhanced efficiency of 24.02%. In addition, the double-column π-π stacking of Z-W-03 results in high hole mobility (~10-4 cm2 V-1 s-1) even without p-dopant. Moreover, when the surface interface is modified, the undoped Z-W-03 device can achieve an efficiency of nearly 23%. Compared to the PSCs using spiro-OMeTAD, those with Z-W-03 exhibit enhanced stability under N2 and ambient conditions.

6.
Mar Drugs ; 21(3)2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36976230

RESUMEN

Seven new polyketides, including four indenone derivatives, cytoindenones A-C (1, 3-4), 3'-methoxycytoindenone A (2), a benzophenone derivative, cytorhizophin J (6), and a pair of tetralone enantiomers, (±)-4,6-dihydroxy-5-methoxy-α-tetralone (7), together with a known compound (5) were obtained from the endophytic fungus Cytospora heveae NSHSJ-2 isolated from the fresh stem of the mangrove plant Sonneratia caseolaris. Compound 3 represented the first natural indenone monomer substituted by two benzene moieties at C-2 and C-3. Their structures were determined by the analysis of 1D and 2D NMR, as well as mass spectroscopic data, and the absolute configurations of (±)-7 were determined on the basis of the observed specific rotation value compared with those of the tetralone derivatives previously reported. In bioactivity assays, compounds 1, 4-6 showed potent DPPH· scavenging activities, with EC50 values ranging from 9.5 to 16.6 µM, better than the positive control ascorbic acid (21.9 µM); compounds 2-3 also exhibited DPPH· scavenging activities comparable to ascorbic acid.


Asunto(s)
Ascomicetos , Tetralonas , Antioxidantes/farmacología , Ascomicetos/química , Benzofenonas/farmacología , Ácido Ascórbico , Estructura Molecular
7.
Int J Mol Sci ; 24(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38003285

RESUMEN

Four new sorbicillinoids, named trichodermolide E (1), trichosorbicillin J (2), bisorbicillinolide B (3), and demethylsorbiquinol (5), together with eight known compounds (4, 6-12), were isolated from the cultures of the mangrove-derived fungus Trichoderma reesei BGRg-3. The structures of the new compounds were determined by analyzing their detailed spectroscopic data, while the absolute configurations were further determined through electronic circular dichroism calculations. Snatzke's method was additionally used to determine the absolute configurations of the diol moiety in 1. In a bioassay, compounds 7 and 10 performed greater inhibitory activities on interleukin-6 and interleukin-1ß than the positive control (dexamethasone) at the concentration of 25 µM. Meanwhile, compounds 5 and 6 showed potent effects with stronger inhibition than dexamethasone on IL-1ß at the same concentration.


Asunto(s)
Hypocreales , Trichoderma , Interleucina-6 , Interleucina-1beta , Trichoderma/química , Dicroismo Circular , Dexametasona , Estructura Molecular
8.
Molecules ; 28(9)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37175149

RESUMEN

Three small molecule organic compounds based on conjugated acetylene-linked methoxy triphenylamine terminal groups with different substituted thiophene cores were synthesized and firstly applied as hole-transporting materials (HTMs). The electron-deficient acetylene linkers can tune the energy levels of frontier molecular orbitals. The physical property measurements show that the HTMs (CJ-05, CJ-06, and CJ-07) possess good stability, hydrophobicity, and film-forming ability. Further, the HTMs were applied in the MAPbI3-based perovskite solar cells (PSCs), and the best power conversion efficiency (PCE) of 6.04%, 6.77%, and 6.48% was achieved, respectively, which implies that they exhibit great potential in photovoltaic applications.

9.
Molecules ; 28(24)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38138501

RESUMEN

Photocatalysis has emerged as a highly promising, green, and efficient technology for degrading pollutants in wastewater. Among the various photocatalysts, Bismuth tungstate (Bi2WO6) has gained significant attention in the research community due to its potential in environmental remediation and photocatalytic energy conversion. However, the limited light absorption ability and rapid recombination of photogenerated carriers hinder the further improvement of Bi2WO6's photocatalytic performance. This review aims to present recent advancements in the development of Bi2WO6-based photocatalysts. It delves into the photocatalytic mechanism of Bi2WO6 and summarizes the achieved photocatalytic characteristics by controlling its morphology, employing metal and non-metal doping, constructing semiconductor heterojunctions, and implementing defective engineering. Additionally, this review explores the practical applications of these modified Bi2WO6 photocatalysts in wastewater purification. Furthermore, this review addresses existing challenges and suggests prospects for the development of efficient Bi2WO6 photocatalysts. It is hoped that this comprehensive review will serve as a valuable reference and guide for researchers seeking to advance the field of Bi2WO6 photocatalysis.

10.
Molecules ; 28(14)2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37513256

RESUMEN

Nardosinone, a predominant bioactive product from Nardostachys jatamansi DC, is well-known for its promising therapeutic applications, such as being used as a drug on anti-inflammatory, antidepressant, cardioprotective, anti-neuroinflammatory, anti-arrhythmic, anti-periodontitis, etc. However, its stability under varying environmental conditions and its degradation products remain unclear. In this study, four main degradation products, including two previously undescribed compounds [2-deoxokanshone M (64.23%) and 2-deoxokanshone L (1.10%)] and two known compounds [desoxo-narchinol A (2.17%) and isonardosinone (3.44%)], were firstly afforded from the refluxed products of nardosinone in boiling water; their structures were identified using an analysis of the extensive NMR and X-ray diffraction data and the simulation and comparison of electronic circular dichroism spectra. Compared with nardosinone, 2-deoxokanshone M exhibited potent vasodilatory activity without any of the significant anti-neuroinflammatory activity that nardosinone contains. Secondly, UPLC-PDA and UHPLC-DAD/Q-TOF MS analyses on the degradation patterns of nardosinone revealed that nardosinone degraded more easily under high temperatures and in simulated gastric fluid compared with the simulated intestinal fluid. A plausible degradation pathway of nardosinone was finally proposed using nardosinonediol as the initial intermediate and involved multiple chemical reactions, including peroxy ring-opening, keto-enol tautomerization, oxidation, isopropyl cleavage, and pinacol rearrangement. Our findings may supply certain guidance and scientific evidence for the quality control and reasonable application of nardosinone-related products.


Asunto(s)
Sesquiterpenos , Sesquiterpenos/química , Temperatura , Sesquiterpenos Policíclicos , Antiinflamatorios
11.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6396-6402, 2023 Dec.
Artículo en Zh | MEDLINE | ID: mdl-38211996

RESUMEN

A quantitative proton nuclear magnetic resonance(qHNMR) method was established to determine the glucose content in commercially available Massa Medicata Fermentata(MMF) products and explore the variations of glucose content in MMF products during processing. The qHNMR spectrum of MMF in deuterium oxide was obtained with 2,2,3,3-d_4-3-(trimethylsilyl) propionate sodium salt as the internal standard substance. With the doublet peaks of terminal hydrogen of glucose with chemical shift at δ 4.65 and δ 5.24 as quantitative peaks, the content of glucose in MMF samples was determined. The glucose content showed a good linear relationship within the range of 0.10-6.44 mg·mL~(-1). The relative standard deviations(RSDs) of precision, stability, repeatability, and recovery for determination were all less than 2.3%. The glucose content varied in different commercially available MMF samples, which were associated with the different fermentation days, wheat bran-to-flour ratios, and processing methods. The glucose content in MMF first increased and then decreased over the fermentation time. Compared with the MMF products fermented with wheat bran or flour alone, the products fermented with both wheat bran and flour had increased glucose. The glucose content of bran-fried MMF was slightly lower than that of raw MMF, while the glucose content in charred MMF was extremely low. In conclusion, the qHNMR method established in this study is simple, fast, and accurate, serving as a new method for determining the glucose content in MMF. Furthermore, this study clarifies the variations of glucose content in MMF during processing, which can not only indicate the processing degree but also provide a scientific basis for revealing the fermentation mechanism and improving the quality control of MMF.


Asunto(s)
Medicamentos Herbarios Chinos , Protones , Medicamentos Herbarios Chinos/química , Fibras de la Dieta , Espectroscopía de Resonancia Magnética
12.
Molecules ; 27(18)2022 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-36144657

RESUMEN

As a traditional Chinese medicine, Eucommia ulmoides Oliver (E. ulmoides Oliv.) is an important medicinal plant, and its barks, male flowers, leaves, and fruits have high value of utilization. The seed meal of E. ulmoides Oliv. is the waste residue produced after oil extraction from seeds of E. ulmoides Oliv. Though the seed meal of E. ulmoides Oliv. is an ideal feed additive, its medicinal value is far from being developed and utilized. We identified six natural iridoid compounds from the seed meal of E. ulmoides Oliv., namely geniposidic acid (GPA), scyphiphin D (SD), ulmoidoside A (UA), ulmoidoside B (UB), ulmoidoside C (UC), and ulmoidoside D (UD). Six natural iridoid compounds were validated to have anti-inflammatory activities. Hence, six compounds were quantified at the optimum extracting conditions in the seed meal of E. ulmoides Oliv. by an established ultra-performance liquid chromatography (UPLC) method. Some interesting conversion phenomena of six tested compounds were uncovered by a systematic study of stability performed under different temperatures and pH levels. GPA was certified to be stable. SD, UA, and UC were only hydrolyzed under strong alkaline solution. UB and UD were affected by high temperature, alkaline, and strong acid conditions. Our findings reveal the active compounds and explore the quantitative analysis of the tested compounds, contributing to rational utilization for the seeds residues of E. ulmoides Oliv.


Asunto(s)
Eucommiaceae , Eucommiaceae/química , Glucósidos Iridoides , Glicósidos Iridoides/análisis , Iridoides/análisis , Semillas/química
13.
Biochem J ; 477(19): 3833-3838, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-32969463

RESUMEN

Post-translational modifications play important roles in mediating protein functions in a wide variety of cellular events in vivo. HEMK2-TRMT112 heterodimer has been reported to be responsible for both histone lysine methylation and eukaryotic release factor 1 (eRF1) glutamine methylation. However, how HEMK2-TRMT112 complex recognizes and catalyzes eRF1 glutamine methylation is largely unknown. Here, we present two structures of HEMK2-TRMT112, with one bound to SAM and the other bound with SAH and methylglutamine (Qme). Structural analyses of the post-catalytic complex, complemented by mass spectrometry experiments, indicate that the HEMK2 utilizes a specific pocket to accommodate the substrate glutamine and catalyzes the subsequent methylation. Therefore, our work not only throws light on the protein glutamine methylation mechanism, but also reveals the dual activity of HEMK2 by catalyzing the methylation of both Lys and Gln residues.


Asunto(s)
Glutamina/química , Metiltransferasas/química , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/química , Glutamina/metabolismo , Humanos , Metilación , Metiltransferasas/metabolismo , Estructura Cuaternaria de Proteína , Metiltransferasa de ADN de Sitio Específico (Adenina Especifica)/metabolismo
14.
Anal Chem ; 92(4): 2953-2960, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31941275

RESUMEN

Self-accumulation of amyloid-ß protein (Aß) into insoluble fibrils is the major hallmark of Alzheimer's disease. Real-time monitoring of fibril growth is essential for clarifying the mechanism underlying aggregation and discovering therapeutic targets. A variety of approaches including NMR, electron microscopy (EM), atomic force microscopy (AFM), and total internal reflection fluorescence microscopy (TIRFM) have been explored to monitor the fibril growth or reveal morphology of Aß aggregates. However, none of the methods allow real-time observation under physiological conditions while without any perturbations. Here, we present a fluorescent probe [Ru(phen)2(fipc)]2+ (Ru-fipc) (phen = 1,10-phenanthroline, fipc = 5-fluoro-N-(1,10-phenanthrolin-5-yl)-1H-indole-2-carboxamide) that can bind to all the Aß forms, i.e., monomers, oligomers, and fibrils, while not perturbing aggregation. Using this probe in combination with laser confocal microscopy, the entire aggregation process could be clearly and exactly imaged at the single fibril level. The reliability of Ru-fipc was confirmed based on colocalization with thioflavin T (ThT). Importantly, Ru-fipc can be used to monitor the very early nucleation and oligomerization process, which is thought to be a critical step in the development of neurotoxicity while it cannot be visualized with ThT. To our knowledge, this is the first fluorescent probe developed for real-time monitoring of Aß aggregation, especially for the very early assembly stage, in solution with minimal perturbation. This method is suitable for in vitro and in vivo studies. We believe this would provide a valuable complementary tool for the study of pathogenesis and discovery of therapeutic targets of neurodegenerative diseases.


Asunto(s)
Péptidos beta-Amiloides/química , Complejos de Coordinación/química , Colorantes Fluorescentes/química , Rutenio/química , Animales , Encéfalo , Complejos de Coordinación/síntesis química , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Células PC12 , Agregado de Proteínas , Ratas , Resonancia por Plasmón de Superficie , Factores de Tiempo
15.
Chirality ; 32(3): 324-333, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31877236

RESUMEN

A simple and sensitive method has been established based on pass-through cleanup and high-performance liquid chromatography quadrupole-orbitrap mass spectrometry (HPLC-Q/Orbitrap MS) for the simultaneous determination of ten aminoglycosides (AGs) in aquatic feeds. The extraction solution and cleanup procedure had been optimized, and good sensitivity, accuracy, and precision were obtained. The calibration curves of AGs were linearity (R2 > 0.99) in the range of 2.0 to 200 µg/L (or 5.0 to 500 µg/L). The limits of detection of AGs were between 10 and 25 µg/kg. The recoveries of AGs ranged from 74.9% to 94.3%, and the intraday and interday relative standard deviations were less than 15%. Finally, this method was successfully applied to determine ten AGs in 30 aquatic feed samples. It might be the first time to use pass-through cleanup approach combined with HPLC-Q/Orbitrap MS method for AGs determination in aquatic feed samples.


Asunto(s)
Aminoglicósidos/análisis , Alimentación Animal/análisis , Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos , Aminoglicósidos/química , Animales , Antibacterianos/química , Calibración , China , Crustáceos/química , Peces , Límite de Detección , Reproducibilidad de los Resultados
16.
Chemistry ; 25(51): 11903-11909, 2019 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-31274212

RESUMEN

Molecular or supramolecular level photoluminescence (PL) modulation combining chemical and photonic input/output signals together in an integrated system can provide potential high-density data memorizing and process functions intended for miniaturized devices and machines. Herein, a PL-responsive supramolecular coordination cage has been demonstrated for complex interactions with redox-active guests. PL signals of the cage can be switched and modulated by adding or retracting Fc derivatives or converting TTF into different oxidation states through chemical or photochemical pathways. As a result, reversible or stepwise PL responses are displayed by these host-guest systems because of the occurrence of photoinduced electron-transfer (PET) or fluorescence resonance energy transfer (FREnT) processes, providing unique nanodevice models bearing off/on logic gates or memristor-like sequential memory and Boolean operation functions.

17.
Inorg Chem ; 58(16): 10736-10742, 2019 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-31390188

RESUMEN

A new Cu4I4-cluster-based compound is constructed to show multifaceted photoluminescent attributes: (1) ultraviolet (UV)-excited thermo-, mechano-, and rigido-chromic phosphorescence by the OPA (one-photon absorption) pathway, due to the interchanging emissions from cluster-centered (3CC) and halide-to-ligand charge-transfer (3XLCT) excited triplet states, (2) the ability to convert X/γ-ray and near-infrared (NIR) radiation to visible-light emission, in which the heavy Cu4I4 cores serve as the efficient X/γ-PEA (photoelectric absorption) or NIR-TPA (two-photon absorption) trapper and convertor to photons in the visible spectrum from the same emissive triplet states as those produced by UV excitation. This all-in-one compound affords a highly integrated nanolab for understanding and exploiting a wide range of photophysical phenomena simultaneously and is further fabricated into fiber-coupled long-range, in situ cryogenic thermometer and poly(methyl methacrylate) (PMMA)-embedded monolith gel, providing access to advanced applications in multifunctional optical materials and devices.

18.
Molecules ; 24(18)2019 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-31533222

RESUMEN

Multiclass screening of drugs with high resolution mass spectrometry is of great interest due to its high time-efficiency and excellent accuracy. A high-scale, fast screening method for pesticides in fishery drugs was established based on ultrahigh performance liquid chromatography tandem quadrupole-Orbitrap high-resolution mass spectrometer. The target compounds - were diluted in methanol and extracted by ultrasonic treatment, and the extracts were diluted with MeOH-water (1:1, v/v) and centrifuged to remove impurities. The chromatographic separation was performed on an Accucore aQ-MS column (100 mm × 2.1 mm, 2.6 µm) with gradient elution using 0.1% formic acid in water (containing 5 mmol/L ammonium formate) and 0.1% formic acid in methanol (containing 5 mmol/L ammonium formate) in Full Scan/dd-MS2 (TopN) scan mode. A screening database, including mass spectrometric and chromatographic information, was established for identification of compounds. The screening detection limits of methods ranged between 1-500 mg/kg, the recoveries of real samples spiked with the concentration of 10 mg/kg and 100 mg/kg standard mixture ranged from 70% to 110% for more than sixty compounds, and the relative standard deviations (RSDs) were less than 20%. The application of this method showed that target pesticides were screened out in 10 samples out of 21 practical samples, in which the banned pesticide chlorpyrifos were detected in 3 out of the 10 samples.


Asunto(s)
Cromatografía Líquida de Alta Presión , Peces , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Espectrometría de Masas en Tándem , Animales , Cromatografía Líquida de Alta Presión/métodos , Explotaciones Pesqueras , Análisis de los Alimentos/métodos , Espectrometría de Masas en Tándem/métodos
19.
Chemistry ; 24(71): 19053-19059, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30222213

RESUMEN

Two 9,10-distyrylanthracene-based luminophores exhibiting aggregation-induced emission and stimuli-responsive properties were synthesized. Seven- or five-color luminescence switching based on a single organic molecule was achieved for the first time. These phase transitions can be induced by physical stimuli such as grinding by mortar and pestle, heating, and exposure to the vapors of organic solvents. Moreover, a strategy for the design of new mechanoresponsive materials with π-conjugated luminophores is proposed.

20.
Anal Bioanal Chem ; 410(22): 5545-5553, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29748759

RESUMEN

A quick screening method of more than 200 pharmaceutical and other residues in aquatic foods based on ultrahigh-performance liquid chromatography-quadrupole-Orbitrap mass spectrometry (UHPLC-Q/Orbitrap MS) was established. In this method, after the addition of 200 µL of 1 M EDTA-Na2, 2 g of each sample homogenate was extracted successively with 10 mL of acetonitrile and 10 mL of ethyl acetate. The extracts were combined, dried under nitrogen flow, and redissolved in 0.1% formic acid in acetonitrile/water (4:6, v/v) for analysis. The prepared samples were analyzed by UHPLC- Q/Orbitrap MS system in Full MS/ddMS2 (full-scan data-dependent MS/MS) mode. Compound identification was performed through comparison of the sample data with the database for standard chemicals, including the retention time, precursor ion, product ions, and isotope pattern for all 206 compounds. Five different aquatic food matrices (carp, shrimp, crab, eel, and mussel) spiked with the analytes at 1, 10, and 50 ng/g were evaluated to assess recoveries, precision, matrix effects, stability, and detection limits using the method. UHPLC analyses required 25 min, and 178-200 analytes met identification criteria at 50 ng/g depending on the matrix. Furthermore, practical application of this method for real samples displayed strong screening capability. Graphical abstract A quick screening method of >200 pharmaceutical and other residues in aquatic foods based on ultrahighperformance liquid chromatography-quadrupole-Orbitrap mass spectrometer was established. Fivedifferent aquatic food matrices, including carp, shrimp, crab, eel and mussel, were studied to evaluatescreen limit at 1, 10 and 50 µg·kg-1 level. Results suggest the high reliability, high time-efficiency and goodsimplicity of the method.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Contaminación de Alimentos/análisis , Plaguicidas/análisis , Preparaciones Farmacéuticas/análisis , Alimentos Marinos/análisis , Espectrometría de Masas en Tándem/métodos , Animales , Peces , Análisis de Peligros y Puntos de Control Críticos/métodos , Límite de Detección
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