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1.
Small ; 20(1): e2304512, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37653588

RESUMEN

The development of high performance electrocatalysts for effective hydrogen production is urgently needed. Herein, three hybrid catalysts formed by WS2 and Co-based metal-organic frameworks (MOFs) derivatives are constructed, in which the small amount of W in the MOFs derivatives acts as a bridge to provide the charge transfer channel and enhance the stability. In addition, the effects of the surface charge distribution on the catalytic performance are fully investigated. Due to the optimal interfacial electron coupling and rearrangement as well as its unique porous morphology, WS2 @W-CoPx exhibits superior bifunctional performance in alkaline media with low overpotentials in hydrogen evolution reaction (HER) (62 mV at 10 mA cm-2 ) and oxygen evolution reaction (OER) (278 mV at 100 mA cm-2 ). For overall water splitting (OWS), WS2 @W-CoPx only requires a cell voltage of 1.78 V at 50 mA cm-2 and maintains good stability within 72 h. Density functional theory calculations verify that the combination of W-CoPx with WS2 can effectively enhance the activity of OER and HER with weakened OH (or O) adsorption and enhanced H atom adsorption. This work provides a feasible idea for the design and practical application of WS2 or phosphide-based catalysts in OWS.

2.
Small ; : e2402478, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778729

RESUMEN

Direct electrolysis of seawater to generate hydrogen is an attractive approach for storing renewable energy. However, direct seawater splitting suffers from low current density and limited operating stability, which severely hinders its industrialization. Herein, a promising strategy is reported to obtain a nano needle-like array catalyst-CDs-Mn-CoxP on nickel foam, in which the Mn─O─C bond tightly binds Mn, Carbon dots (CDs), and CoxP together. The coordination engineering of CDs and Mn not only effectively regulates the electronic structure of CoxP, but also endows the as-prepared catalyst with selectivity and marked long-term stability at ampere-level current density. Low overpotentials of 208 and 447 mV are required to achieve 1000 mA cm-2 for hydrogen evolution reaction (HER) and Oxygen evolution reaction (OER) in simulated seawater, respectively. Cell potentials of 1.78 and 1.86 V are needed to reach 500 and 1000 mA cm-2 in alkaline seawater along with excellent durability for 350 h. DFT studies have verified that the introduction of Mn and CDs effectively shifts the d-band center of Co-3d toward higher energy, thereby strengthening the adsorption of intermediates and enhancing the catalytic activity. This study sheds light on the development of highly effective and stable catalysts for large-scale seawater electrolysis.

3.
J Magn Reson Imaging ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38415884

RESUMEN

BACKGROUND: Ultrasonography (US), as a routine examination for evaluating coronary artery lesions (CAL) in children with Kawasaki disease (KD), has strong subjectivity and limitations. Non-contrast enhanced coronary magnetic resonance angiography (NCE-CMRA) is sensitive and reliable in displaying the segments of coronary arteries (CA). PURPOSE: To evaluate the CA using NCE-CMRA, to compare NCE-CMRA with US, and to assess the correlation between KD-related inflammatory factors and the occurrence of CAL. STUDY TYPE: Retrospective. POPULATION: 61 children with KD who had undergone NCE-CMRA. Ultimately, 52 cases were included (32 males and 20 females), with an average of 5.9 ± 0.3 years old. FIELD STRENGTH/SEQUENCE: 3-T, 3D balanced turbo field echo sequence. ASSESSMENT: NCE-CMRA and US coronary visualization rates were compared in 41 children who were imaged with both techniques. Inflammatory factors were compared between CAL and normal coronary artery (NCA) subgroups. In the CAL group, correlations of these inflammatory factors with CAL parameters were investigated. STATISTICAL TESTS: Comparison between groups was performed by the two independent samples t-test; the comparison of enumeration data between groups was performed by chi-square test. Receiver operating characteristic (ROC) curve analysis was performed to determine the sensitivity of inflammatory factors for detecting CAL. The correlation between CAL and inflammatory indexes was analyzed by multiple linear regression. A P value <0.05 was considered statistically significant. RESULTS: NCE-CMRA visualized significantly more segments than US (76% vs. 46%). There were significant differences in PLT, CRP, ESR, and D-dimer between the CAL and NCA groups. ROC curve analysis showed that the sensitivities of these four indicators in diagnosing CAL were 39%, 44%, 72%, and 61%, respectively, at cut-off points of 562.5 × 109 /L, 48.93 mg/L, 45.5 mm/h, and 0.5 mg/L, respectively. DATA CONCLUSION: The combination of NCE-CMRA and inflammatory factors is helpful for the early diagnosis and disease severity of CAL in children with KD. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

4.
Soft Matter ; 20(22): 4422-4433, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38775112

RESUMEN

Biogenic purine crystals can function in vision as light scatters, mirrors, and multilayer reflectors and produce structural colors or depolarization for camouflage. Xanthine crystals form irregular multifocal mirrors in the median ocellus of Archaeognatha. It is important to broaden the study of crystallization strategies to obtain organic crystals with purine rings in the laboratory. In this work, a facile one-step synthesis route to fabricate bio-inspired xanthine crystals is reported for the first time. The obtained rhomboidal xanthine nanoplates have similar morphology and size to biogenic xanthine crystals. Their length and thickness are about 2-4 µm and 50 nm, respectively. Lattice parameters, crystal structure, formation mechanism and optical properties of synthetic single-crystalline xanthine nanoplates were investigated in detail in this work. The obtained xanthine nanoplate crystals are proposed to be anhydrous xanthine with monoclinic symmetry, and the xanthine nanoplates mainly expose the (100) plane. It is proposed that the anhydrous xanthine nanoplates are formed via an amorphous xanthine intermediate precursor. The synthetic anhydrous xanthine nanoplates exhibit excellent optical properties, including high diffuse reflectivity, strong depolarization and pearlescent luster. This work provides a new design to synthesize bio-inspired organic molecular crystals with excellent optical properties.

5.
Phytopathology ; : PHYTO05230173R, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38377011

RESUMEN

Fusarium root rot is usually classified as an extremely destructive soilborne disease. From 2020 to 2021, Fusarium root rot was observed in production areas and seriously affected the yield and quality of Scutellaria baicalensis in Shanxi Province, China. Based on morphological characteristics and combined analysis of the internal transcribed spacer region of ribosomal DNA and translation elongation factor 1-alpha sequences, 68 Fusarium isolates obtained in this work were identified as F. oxysporum (52.94%), F. acuminatum (20.59%), F. solani (16.17%), F. proliferatum (5.88%), F. incarnatum (2.94%), and F. brachygibbosum (1.47%). In the pathogenicity tests, all Fusarium isolates could infect S. baicalensis roots, presenting different pathogenic ability. Among these isolates, F. oxysporum was found to have the highest virulence on S. baicalensis roots, followed by F. acuminatum, F. solani, F. proliferatum, F. brachygibbosum, and F. incarnatum. According to fungicide sensitivity tests, Fusarium isolates were more sensitive to fludioxonil and difenoconazole, followed by carbendazim, thiophanate-methyl, and hymexazol. In brief, this is the first report of Fusarium species (F. oxysporum, F. acuminatum, F. solani, F. proliferatum, F. incarnatum, and F. brachygibbosum) as causal agents of root rot of S. baicalensis in Shanxi Province, China. The fungicide sensitivity results will be helpful for formulating management strategies of S. baicalensis root rot.

6.
Small ; 19(31): e2300883, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37029573

RESUMEN

Carbon dots (CDs) with good water solubility and biocompatibility have become a research hotspot in the nano-enzyme and biomedical field. However, the problems of low catalytic activity and ambiguous catalytic site of CDs as nanozymes still need to be addressed. In this work, CDs loaded with Cu single atoms are obtained through pyrolysis, and the coordination structure and surface functional groups are regulated by adjusting the pyrolysis temperature. CDs obtained at 300 °C (named Cu-CDs-300) have the most carboxyl content and Cu is coordinated in the form of CuN2 O2 , which can better decompose H2 O2 to produce free radical and is beneficial to catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB). The vmax is 6.56*10-7  m s-1 , 6.56 times higher than that of horseradish peroxidase (HRP). Moreover, Cu-CDs-300 can effectively lead to CT26 apoptosis by generating much free radicals. This work demonstrates the synergistic effect of oxygen-containing functional groups and metal coordination structures on peroxide-like activity of CDs and provides new ideas for the design of clear active structure and high efficiency peroxide-like single atom CDs catalyst.

7.
Chemistry ; 29(31): e202300004, 2023 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-36935356

RESUMEN

Biomimetic synthesis of guanine crystals has been focused on in the last years. However, multi-functional guanine crystals occluded with fluorescent molecules have not been realized in the laboratory. Here, the controllable synthesis of guanine crystal microplatelets with fluorescence and pearlescence was achieved for the first time by incorporating Nile red (NR) or fluorescein isothiocyanate (FITC) molecules into guanine crystals. The synthesized fluorescent guanine crystals are pure ß-phase anhydrous guanine single crystals. Aqueous suspensions with NR- and FITC-doped guanine crystals exhibit distinct pearlescence. The fluorescence intensities of NR and FITC were greatly enhanced after being doped into guanine crystals due to the inhibition of aggregation-caused quenching. Moreover, films composed of fluorescent guanine microplatelets exhibit high diffuse reflection intensity (70 %). This work provides a strategy to synthesize multifunctional materials composed of organic crystals occluded with dyes.

8.
Eur Radiol ; 33(12): 8464-8476, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37378712

RESUMEN

OBJECTIVE: Myocardial extracellular volume (ECV) fraction is an important imaging biomarker in clinical decision-making. CT-ECV is a potential alternative to MRI for ECV quantification. We conducted a meta-analysis to comprehensively assess the reliability of CT for ECV quantification with MRI as a reference. METHODS: We systematically searched PubMed, EMBASE, and the Cochrane Library for relevant articles published since the establishment of the database in July 2022. The articles comparing CT-ECV with MRI as a reference were included. Meta-analytic methods were applied to determine the pooled weighted bias, limits of agreement (LOA), and correlation coefficient (r) between CT-ECV and MRI-ECV. RESULTS: Seventeen studies with a total of 459 patients and 2231 myocardial segments were included. The pooled mean difference (MD), LOA, and r for ECV quantification at the per-patient level was (0.07%; 95% LOA: - 0.42 to 0.55%) and 0.89 (95% CI: 0.86-0.91), respectively, while on the per-segment level was (0.44%; 95% LOA: 0.16-0.72%) and 0.84 (95% CI: 0.82-0.85), respectively. The pooled r from studies with the ECViodine method for ECV quantification was significantly higher compared to those with the ECVsub method (0.94 (95% CI: 0.91-0.96) vs. 0.84 (95% CI: 0.80-0.88), respectively, p = 0.03). The pooled r from septal segments was significantly higher than those from non-septal segments (0.88 (95% CI: 0.86-0.90) vs. 0.76 (95% CI: 0.71-0.90), respectively, p = 0.009). CONCLUSION: CT showed a good agreement and excellent correlation with MRI for ECV quantification and is a potentially attractive alternative to MRI. CLINICAL RELEVANCE STATEMENT: The myocardial extracellular volume fraction can be acquired using a CT scan, which is not only a viable alternative to myocardial extracellular volume fraction derived from MRI but is also less time-consuming and costly for patients. KEY POINTS: • Noninvasive CT-ECV is a viable alternative to MRI-ECV for ECV quantification. • CT-ECV using the ECViodine method showed more accurate myocardial ECV quantification than ECVsub. • Septal myocardial segments showed lower measurement variability than non-septal segments for the ECV quantification.


Asunto(s)
Yodo , Miocardio , Humanos , Reproducibilidad de los Resultados , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Valor Predictivo de las Pruebas
9.
Nano Lett ; 22(17): 7203-7211, 2022 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-36000894

RESUMEN

Carbon dots (C-Dots), with unique properties from tunable photoluminescence to biocompatibility, show wide applications in biotechnology, optoelectronic device and catalysis. Chiral C-Dots are expected to have strongly chirality-dependent biological and catalytic properties. For chiral C-Dots, a clear structure and quantitative structure-property relationship need to be clarified. Here, chiral C-Dots were fabricated by electrooxidation polymerization from serine enantiomers. The oxidized serine has a reversed chiral configuration to serine, which leads to the chiral C-Dots possessing inverse handedness compared with their raw materials. Electron circular dichroism spectrum, together with other diverse characterization techniques and theoretical calculations, confirmed that these chiral C-Dots (2-7 nm) have a well-defined primary structure of polycyclic dipeptide and possess a spatial structure with a c-axis of hexagonal symmetry and two cyclic dipeptides as the spatial structural unit. These chiral C-Dots also show enantioselective catalytic activity on DOPA enantiomers oxidation.


Asunto(s)
Carbono , Serina , Carbono/química , Catálisis , Dicroismo Circular , Estereoisomerismo
10.
Mikrochim Acta ; 189(8): 285, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35851426

RESUMEN

A large-size Bi2Se3 tape electrode (BTE) was prepared by peeling off a 2 × 1 × 0.5 cm high-quality single crystal. The feasibility of using the flexible BTE as an efficient bioplatform to load Au nanoparticles and probe DNA for HIV-1 DNA electrochemical sensing was explored. Differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) show that the resultant biosensor has a wide linear range from 0.1 fM to 1 pM, a low detection limit of 50 aM, excellent selectivity, reproducibility and stability, and is superior to the pM DNA detection level of Pt-Au, graphene-AuNPs hybrid biosensors. This outstanding performance is attributed to the intrinsic surface state of Bi2Se3 topological insulator in facilitating electron transfer. Therefore, BTE electrochemical biosensor platform has great potential in the application for sensitive detection of DNA biomarkers.


Asunto(s)
Técnicas Biosensibles , VIH-1 , Nanopartículas del Metal , Técnicas Biosensibles/métodos , ADN/química , ADN/genética , Electrodos , Oro/química , VIH-1/genética , Nanopartículas del Metal/química , Reproducibilidad de los Resultados
11.
Molecules ; 27(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35458749

RESUMEN

Olanzapine is a commonly used drug in the treatment of schizophrenia, but its clinical application has been restricted by metabolic-related side effects. In order to mitigate the weight gain side effects caused by olanzapine, other drugs with different targets were selected for combined use and evaluated in animal models of schizophrenia. SEP-363856 is a novel psychotropic agent which is under phase III clinical trials for schizophrenia treatment. The aim of the research was to evaluate whether co-administration of olanzapine and SEP-363856 exerts synergistic anti-schizophrenic effects in the apomorphine (APO)-induced climbing test, the MK-801-induced hyperactivity test, and the Morris water maze test, and therefore reduces the weight gain side effects induced by olanzapine. Through isobolographic analysis, the results showed a synergistic interaction in the climbing test; the experimental ED30 (3 mg/kg) was significantly smaller (p < 0.05) than the theoretical ED30 (5 mg/kg). Additionally, such potentiating effects appeared additive in the MK-801 challenge experiment. Co-treatment with an effective dose of olanzapine and a low dose of SEP-363856 reversed MK-801-induced cognitive impairment symptoms in mice. Moreover, combination treatment with olanzapine and SEP-363856 controls sustained weight gain in mice with chronic exposure to olanzapine. These results support further clinical trials to test the effectiveness of co-treatment of olanzapine and SEP-363856 for controlling symptoms and weight gain in patients with schizophrenia during antipsychotic treatments.


Asunto(s)
Antipsicóticos , Esquizofrenia , Animales , Antipsicóticos/efectos adversos , Benzodiazepinas/efectos adversos , Maleato de Dizocilpina/farmacología , Humanos , Ratones , Olanzapina , Piranos , Esquizofrenia/inducido químicamente , Esquizofrenia/tratamiento farmacológico , Aumento de Peso
12.
Water Sci Technol ; 86(5): 1193-1206, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36358055

RESUMEN

Considering the urgent need for the analysis of trace-level pollutants in water samples, the pre-concentration of micropollutants in water samples has been the focus of extensive research. Among current pretreatment methods, the solid phase extraction (SPE) technique has received enormous attention because of its low cost, ease of operation and high efficiency. In this work, a new adsorbent (Fe3O4@Au@DTC NPs) was acquired through modification of Fe3O4 nanoparticles (NPs) with gold (Au) and dithiocarbamate (DTC). To investigate their application ability, the adsorbent were utilized as an SPE adsorbent to enrich polycyclic aromatic hydrocarbons in water (PAHs, fluoranthene, pyrene, benzo anthracene, benzo fluoranthene, benzo pyrene). The obtained Fe3O4@Au@DTC NPs were confirmed by transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), and UV-Vis spectrum. Under optimal conditions, the calibration curves were obtained in the range of 10-500 ng L-1, while the limit of detection (LOD) ranged in 1.17-2.31 ng L-1. Furthermore, 50 mg of Fe3O4@Au@DTC NPs could extract trace PAHs from 500 mL real water samples into 1 mL eluent, and the spiked recoveries of five PAHs in river water and tap water reached 72-106% with relative standard deviations varying between 3.3-5.18%. Through the conversion of amines into DTC, we acquire desiring group modified Fe3O4 NPs, which showed great prospects in magnetic solid-phase extraction sphere and environmental field.


Asunto(s)
Nanopartículas de Magnetita , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Hidrocarburos Policíclicos Aromáticos/análisis , Nanopartículas de Magnetita/química , Contaminantes Químicos del Agua/análisis , Extracción en Fase Sólida/métodos , Límite de Detección , Agua , Pirenos/análisis
13.
Mol Carcinog ; 60(11): 746-757, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34411338

RESUMEN

Programmed death-ligand 1 (PD-L1)-mediated resistance has become a great challenge for tumor treatment. Cisplatin increased tumor PD-L1 expression, promoted chemotherapy resistance. Interferon-γ (IFN-γ)-induced PD-L1 expression might facilitate immunotherapy resistance. Methylseleninic acid (MSeA), a selenium (Se) compound, offered superior cancer chemo-preventive activities and enhanced tumor sensitivity to diverse chemotherapeutic drugs. This study explored the effects of MSeA on the PD-L1-mediated resistance using both in vitro and in vivo models. Results showed that MSeA substantially attenuated cisplatin-induced PD-L1 expression via inhibiting protein kinase B phosphorylation, thereby potentiated cisplatin cytotoxicity in prostate and lung cancer cell models. In lung cancer xenograft model, MSeA significantly suppressed cisplatin-induced PD-L1 expression, consequently enhanced T-cell immunity, ultimately improved the therapeutic efficacy of cisplatin. Moreover, IFN-γ-induced tumor PD-L1 expression was remarkably reduced by MSeA, with correlated reductions in janus kinase 2 and signal transducer and activator of transcription 3 (STAT3) phosphorylation in prostate and lung cancer cell models. Our findings, for the first time, demonstrated that MSeA is a potential agent to overcome PD-L1-mediated chemotherapy and immunotherapy resistance. Such information might have potential clinical implications for prostate and lung cancer treatment.


Asunto(s)
Antígeno B7-H1/metabolismo , Cisplatino/administración & dosificación , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Compuestos de Organoselenio/administración & dosificación , Neoplasias de la Próstata/tratamiento farmacológico , Células A549 , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cisplatino/farmacología , Sinergismo Farmacológico , Humanos , Interferón gamma/metabolismo , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Compuestos de Organoselenio/farmacología , Fosforilación , Neoplasias de la Próstata/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Soft Matter ; 17(7): 1955-1962, 2021 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-33427846

RESUMEN

Biogenic guanine crystals exhibit excellent optical properties owing to their extremely high refractive index. However, there is no report related to the highly-ordered guanine assemblies in the synthetic systems. Herein, ß-phase anhydrous guanine (ß-AG) microrods were formed in mixed solvents of formamide and water in the presence of small organic molecules such as uric acid, pyrrole (Py), N-methyl-2-pyrrolidone (NMP), N-vinyl-2-pyrrolidone (NVP). The one-dimensional (1D) assembly of ß-AG microrods form spontaneously in water, which is the first reported highly ordered 1D assembly of organic micro- or nanocrystals in the solution. The obtained ß-AG microrods obtained in Py system can form reversible 1D assembly in water after being treated in organic solvents such as ethanol, acetone and isopropanol, which have high solubility in water. However, no reversible 1D assembly but only dispersed or aggregated guanine microrods formed in water after similar treatment in the other three organic solvents such as n-hexane, dichloroethane and petroleum ether with low solubility in water. Similar reversible assembly features can also be observed in other three systems, standard system, and NVP and NMP systems. The reversible 1D assemblies of guanine microrods in water and organic solvents with high solubility in water indicate that there is a strong interaction between the (100) planes of ß-AG microrods in water. The oriented 1D assembly of guanine microrods with long axes perpendicular to the horizontal magnetic field can form in water under magnetic field.


Asunto(s)
Guanina , Agua , 2-Propanol , Solubilidad , Solventes
15.
Soft Matter ; 17(19): 5025-5033, 2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-33912882

RESUMEN

Similar to the crystal growth process, additives have a strong influence on the dissolution process of crystals. Studies on the dissolution process may shed light on understanding the biomineralization and bioinspired crystallization process. The influence of different kinds of additives including surfactants and polymers on the dissolution process of calcite {104} planes was investigated in detail in this work. The additives can be classified into three kinds according to their influence on the dissolution process of calcite under different concentration windows. The additives show three different kinds of dissolution behaviors with the increase of additive concentrations according to the tomographic variation of the calcite surface after the dissolution process. There are four dissolution modes of calcite while changing the additive concentrations in the solution. Rhombohedral etch pits with [4[combining macron]41] and [481[combining macron]] step edges are formed on the calcite {104} planes after the dissolution process at low additive concentrations (mode I). Calcite micropyramids begin to appear on the calcite surface and the densities of micropyramids increase with the increase of the additive concentrations until they cover the entire calcite surface after the dissolution process at medium additive concentrations (mode II). Instead of micropyramids, large pyramids with [481[combining macron]] and [4[combining macron]41] step edges and a size of about 50 µm form after the dissolution process at high additive concentrations (modes III and IV). We propose that the different anisotropic dissolution behaviors of calcite are strongly related to the concentrations and the adsorption features of the additives on the calcite surface. The additives may act as inhibitors of calcite dissolution, possibly through adsorption on calcite surfaces without preferred adsorption, or adsorption at specific kink sites or step edges. The influence of additives on the oriented dissolution of calcite is generally related to the adsorption density and homogeneity of additives on the calcite substrates.

16.
Angew Chem Int Ed Engl ; 60(22): 12585-12590, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33754433

RESUMEN

Here, we show the fabrication of the carbon dots (CDs) with green and orange emissions from PTCDA (perylene-3,4,9,10-tetracarboxylic dianhydride). Using these CDs as emitters, the orange (or green) CDs LEDs were fabricated, which show electroluminescence (EL) spectra centered at 560 nm (or 498 nm) with an external quantum efficiency (EQE) of 1.98 % (1.76 %) adhering a luminescence of 626 cd m-2 (or 519 cd m-2 ). The machine learning was successfully used to predict PL CCT value. With the model, the white photoluminescence (PL) emission with adjustable correlated color temperature (CCT) from 3093 to 11018 K via combining blue, green, and orange CDs was achieved. Then, we obtained the warm white CDs LEDs with CCT of 3107, 4071 and 4548 K, and cold white CDs LEDs with CCT of 5632 (CIE coordinates of (0.33, 0.33), EQE: 1.18 %, luminescence: 598 cd m-2 ) and 6034 K accurately.

17.
Chemistry ; 26(69): 16228-16235, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-32888220

RESUMEN

ß-Phase anhydrous guanine (ß-AG) crystals are one of the most widespread organic crystals to construct optical structures in organisms. Currently, no synthetic method is available that allows for producing guanine crystals with similar control in size, morphology, and crystallography as in biological ones. Herein, a facile one-step synthesis route to fabricate bio-inspired guanine microplatelets with (100) exposing planes in almost pure ß-phase is reported. The synthesis is based on a precipitation process of a guanine sodium hydroxide solution in formamide with poly(1-vinylpyrrolidone-co-vinyl acetate) as a morphological additive. Due to their uniform size (ca. 20 µm) and thickness (ca. 110 nm), the crystals represent the first synthetic guanine microplatelets that exhibit strong structural coloration and pearlescent lusters. Moreover, this synthesis route was utilized as a model system to investigate the effects of guanine analogues, including uric acid, hypoxanthine, xanthine, adenine, and guanosine, during the crystallization process. Our results indicate that the introduction of guanine analogues not only can reduce the required synthesis temperature but also provide a versatile control in crystal morphology and polymorph selection between the α-phase AG (α-AG) and ß-AG. Turbidity experiments show that the ß-AG microplatelets are formed with a fast precipitation rate in comparison to α-AG, suggesting that the formation of ß-AG crystals follows a kinetically driven process.

18.
Small ; 15(48): e1901512, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31074585

RESUMEN

Carbon dots (CDs) have attracted increasing attention in disease therapy owing to their low toxicity and good biocompatibility. Their therapeutic effect strongly depends on the CDs structure (e.g., size or functional groups). However, the impact of CDs chirality on maltase and blood glucose level has not yet been fully emphasized and studied. Moreover, in previous reports, chiral CDs with targeted optical activity have to be synthesized from precursors of corresponding optical rotation, severely limiting chiral CDs design. Here, chiral CDs with optical rotation opposite to that of the precursor are facilely prepared through electrochemical polymerization. Interestingly, their chirality can be regulated by simply adjusting reaction time. At last, the resultant (+)-DCDs (700 µg mL-1 ) are employed to modify maltase in an effort to regulate the hydrolytic rate of maltose, showing an excellent inhibition ratio to maltase of 54.7%, significantly higher than that of (-)-LCDs (15.5%) in the same reaction conditions. The superior performance may be attributed to the preferable combination of DCDs with maltase. This study provides an electrochemical method to facilely regulate CDs chirality, and explore new applications of chiral CDs as antihyperglycemic therapy for controlling blood glucose levels.


Asunto(s)
Carbono/química , Glucosa/análisis , Inhibidores de Glicósido Hidrolasas/farmacología , Puntos Cuánticos/química , alfa-Glucosidasas/metabolismo , Células HEK293 , Humanos , Puntos Cuánticos/ultraestructura
20.
J Clin Nurs ; 27(13-14): 2583-2589, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28401738

RESUMEN

AIMS AND OBJECTIVES: To assess the effects of three different bowel preparation methods on the incidence of infectious complications in patients who underwent transrectal ultrasonography-guided prostate biopsy. BACKGROUND: The standard bowel preparation protocol for prostate biopsy has not been established. DESIGN: A retrospective study in a single centre. METHODS: From January 2013-December 2015, the clinical records of 1,130 patients who underwent prostate biopsy were, respectively, reviewed. All the patients received metronidazole prophylaxis before biopsy. The patients were divided into three groups according to the bowel preparation methods: patients in Group A (n = 402) received only soapy enema; patients in Group B (n = 413) received polyethylene glycol; while patients in Group C (n = 315) received polyethylene glycol plus povidone-iodine enema. Infectious complications were classified as fever (>37.5°C), urinary tract infection and sepsis. The postoperative adverse events were also observed. RESULTS: The overall postbiopsy infectious complications were observed in 48 (4.25%) patients of all the cases, including 23 (5.72%) cases in Group A, 20 (4.84%) cases in Group B and five patients (1.59%) in Group C. There was significant difference among the groups (p = .018). In detail, these infectious complications included 22 (1.95%) cases of fever and 26 (2.30%) cases of urinary tract infection. No sepsis was observed among the total patients. The incidence of adverse events was 14.43% (58/402) occurred in Group A, 25.91% (107/413) in Group B and 26.67% (84/315) in Group C. The difference was statistically significant. CONCLUSIONS: Our study confirmed that combined preparation regimens of polyethylene glycol with povidone-iodine enema could significantly reduce the postbiopsy infection rate. Conventional soapy enema is associated with less adverse events. RELEVANCE TO CLINICAL PRACTICE: Findings of this study provide useful evidence-based information for healthcare professionals. The application of combined preparation regimens of polyethylene glycol with povidone-iodine enema resulted in better improvement in the prevention of postbiopsy infection.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/prevención & control , Biopsia/métodos , Catárticos , Sepsis/prevención & control , Ultrasonido Enfocado Transrectal de Alta Intensidad/métodos , Infecciones Urinarias/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Enema/métodos , Humanos , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Complicaciones Posoperatorias/prevención & control , Povidona Yodada/uso terapéutico , Próstata/diagnóstico por imagen , Estudios Retrospectivos , Resultado del Tratamiento , Ultrasonido Enfocado Transrectal de Alta Intensidad/efectos adversos
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