MoOx-Based Colorimetric Sensor for Ultraviolet Visualization.

Due to the depletion of the global ozone layer and the presence of ozone holes, humans are increasingly exposed to threats from solar ultraviolet radiation. Therefore, researching and developing a highly selective, sensitive, simple, and fast ultraviolet sensor is of significant importance for personal protection. In recent years, new nanomaterials have shown good application prospects in the research of ultraviolet sensors. MoOx nanostructures were prepared by a hydrothermal method. The experimental results show that, compared to traditional photochromic compounds, the new MoOx nanostructures exhibit high uniqueness, high selectivity, and excellent stability, and can perform rapid and accurate detection under full-band light. The beam sensor can not only detect through traditional electrical signal output, but also amplify, display, and analyze the beam through visualization and visual analysis, further improving the reliability and practicality of its application.

Ginkgolide C attenuates cerebral ischemia/reperfusion-induced inflammatory impairments by suppressing CD40/NF-κB pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Ginkgo biloba L. (Ginkgoaceae), a traditional Chinese medicine, has been applied for thousands of years for the treatment of cardio-cerebral vascular diseases in China. It is written in Compendium of Materia Medica that Ginkgo has the property of "dispersing poison", which is now referred to as anti-inflammatory and antioxidant. Ginkgolides are important active ingredients in Ginkgo biloba leaves and ginkgolide injection has been frequently applied in clinical practice for the treatment of ischemic stroke. However, few studies have explored the effect and mechanism of ginkgolide C (GC) with anti-inflammatory activity in cerebral ischemia/reperfusion injury (CI/RI). AIM OF THE STUDY: The present study aimed to demonstrate whether GC was capable of attenuating CI/RI. Furthermore, the anti-inflammatory effect of GC in CI/RI was explored around the CD40/NF-κB pathway. MATERIALS AND METHODS: In vivo, middle cerebral artery occlusion/reperfusion (MCAO/R) model was established in rats. The neuroprotective effect of GC was assessed by neurological scores, cerebral infarct rate, microvessel ultrastructure, blood-brain barrier (BBB) integrity, brain edema, neutrophil infiltration, and levels of TNF-α, IL-1ß, IL-6, ICAM-1, VCAM-1, and iNOS. In vitro, rat brain microvessel endothelial cells (rBMECs) were preincubated in GC before hypoxia/reoxygenation (H/R) culture. The cell viability, levels of CD40, ICAM-1, MMP-9, TNF-α, IL-1ß, and IL-6, and activation of NF-κB pathway were examined. In addition, the anti-inflammatory effect of GC was also investigated by silencing CD40 gene in rBMECs. RESULTS: GC attenuated CI/RI as demonstrated by decreasing neurological scores, reducing cerebral infarct rate, improving microvessel ultrastructural features, ameliorating BBB disruption, attenuating brain edema, inhibiting MPO activity, and downregulating levels of TNF-α, IL-1ß, IL-6, ICAM-1, VCAM-1, and iNOS. Coherently, in rBMECs exposed to H/R GC enhanced cell viability and downregulated levels of ICAM-1, MMP-9, TNF-α, IL-1ß, and IL-6. Furthermore, GC suppressed CD40 overexpression and hindered translocation of NF-κB p65 from the cytosol to the nucleus, phosphorylation of IκB-α, and activation of IKK-ß in H/R rBMECs. However, GC failed to protect rBMECs from H/R-induced inflammatory impairments and suppress activation of NF-κB pathway when CD40 gene was silenced. CONCLUSIONS: GC attenuates cerebral ischemia/reperfusion-induced inflammatory impairments by suppressing CD40/NF-κB pathway, which may provide an available therapeutic drug for CI/RI.

Facile Preparation of Oxygen-Vacancy-Engineered MoOx Nanostructures for Photoreversible Switching Systems.

Photochromic materials have attracted increasing attention. Here, we report a novel photo-reversible color switching system based on oxygen-vacancy-engineered MoOx nanostructures with water/N-methyl-2-pyrrolidone (NMP) as solvents. In this work, the system rapidly changed from colorless to blue under UV irradiation (360-400 nm) and slowly recovered its colorless state under visible light irradiation. The obtained oxygen vacancy-engineered MoOx nanostructures exhibited good repeatability, chemical stability, and cycling stability. Upon UV light irradiation, H+ was intercalated into layered MoOx nanostructures and the Mo6+ concentration in the HxMoOx decreased, while the Mo5+ concentration increased and increased oxygen vacancies changed the color to blue. Then, it recovered its original color slowly without UV light irradiation. What is more, the system was highly sensitive to UV light even on cloudy days. Compared with other reported photochromic materials, the system in this study has the advantage of facile preparation and provides new insights for the development of photochromic materials without dyes.

Electronic engineering of CoSe/FeSe2 hollow nanospheres for efficient water oxidation.

First-row non-precious metal-based catalysts are widely studied and recognized as potential substitutes for precious metal-based catalysts in the oxygen evolution reaction (OER) for hydrogen generation but their application remains challenging. In this study, a unique class of Co-Fe selenide hollow nanospheres (CoSe@FeSe2) is well-designed through a facile hydrothermal method. The in situ formed hybrid composites possess numerous interfaces allowing partial electron transfer via O2- bridges to optimize the adsorption feature of the reaction intermediates, *OH, *O, and *OOH, on the catalysts. The collected surface valence band spectra evidence the optimization of the intermediate adsorption and active sites. The as-synthesized CoSe@FeSe2 exhibits excellent OER activity with a low overpotential of 281 mV to drive a current density of 10 mA cm-2 and a low Tafel slope of 34.3 mV dec-1 in an alkaline electrolyte. Additionally, the advanced catalyst also shows super stability with negligible current density decay after 12 h. This work presents a prototype for the fabrication of highly efficient electrocatalysts using an electronic engineering strategy.

Giant Cell Tumor of Tendon Sheath and Tendinopathy as Early Features of Early Onset Sarcoidosis.

Giant cell tumor of tendon sheath (GCTTS) is characterized by diffuse proliferation of synovial-like cells and multinucleated giant cells along tendon sheaths. This benign tumor typically presents in the third to fourth decade of life and is exceeding rare in children. Here we describe a case of a 10-years-old girl with a history of soft tissue swelling involving the third digit of left hand, bilateral wrists and ankles. Pathology of the finger mass revealed abundant multinucleated giant cells consistent with GCTTS. Resection of the tendinous masses from the ankles also showed multinucleated giant cells along with chronic bursitis. She began to show features of polyarticular arthritis by age 7. Due to progression of arthritis, whole exome sequencing was performed and found a de novo heterozygous mutation in NOD2 (p. R334Q). This variant is the most common mutation responsible for early onset sarcoidosis (EOS)/Blau syndrome, an autoinflammatory disease characterized by granulomatous inflammation of joints, skin and eyes. The early onset of symptoms and presence of multinucleated giant cells and granuloma in this case are in keeping with a diagnosis of EOS/Blau syndrome. The patient responded well to treatment with methotrexate and etanercept. This case extends the clinical spectrum of EOS/Blau syndrome, which should be considered for GCTTS and other unusual presentations of tendon inflammation in children, even in the absence of the characteristic triad of arthritis, dermatitis and uveitis.

High selective detection of mercury (II) ions by thioether side groups on metal-organic frameworks.

Mercury ions can significantly affect the organism and environment even at a very low concentration. Thus, great efforts have been devoted to developing high sensitive electrochemical sensors, especially the one that not only detect the mercury ions but also effective sensitive to thymine-Hg2+-thymine in aqueous solution. Metal-organic-frameworks (MOFs) possess hollow nature and are easy for grafting functional groups, however, there is still no attempts for working as electrochemical sensors in detecting mercury ions. Herein, we report a novel type sensor of Zr(IV)-based MOFs with specifically attached thioether side groups allowing mercury ions to be easily adsorbed and detected. The Zr(IV)-involved MOFs show strong binding to mercury ions compared with the bare MOFs, as confirmed by both experiment measurements and theoretical calculations. The as-prepared senor is sensitive ranging from 0.01 nM to 3 µM with detection limitation of 7.3 fM, which is better than most of T-Hg2+-T- and enzyme-based sensors reported so far. The high sensitivity could be due to the straightforward adsorption pathway and the biomolecule exclusion nature of the Zr(IV)-involved MOFs sensor. We anticipate that our findings could pave the way for MOFs-based sensor exploration towards its commercial applications.

An electrochemical method for plant species determination and classification based on fingerprinting petal tissue.

The identification of plant species not only is a hobby but also has important application value in plant resources science. Traditional plant identification often relies on the experience of botanists. The infrageneric identification of plants is easily mistaken due to similarities in organ features. In this work, we propose an electrochemical method to obtain fingerprints of plant petal tissue. Fourteen species of Lycoris were used as a model for validating this methodology. Pattern and color recognition were established for visualization of electrochemical fingerprints recorded after various solvent extractions. In addition, the infrageneric relationships of these Lycoris species were deduced from the electrochemical fingerprints since the type and content of electroactive compounds in plants are controlled by genes. The results indicate that the electrochemical fingerprints of Lycoris petals are correlated with the infrageneric relationships of native Lycoris species.

Correction to: A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and paracetamol.

The authors of "A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and paracetamol (Microchimica Acta 185, no. 2 (2018): 87)" wish to replace the incorrect images of Fig. 1C, 1D shown below.

Large-scale synthesis of carbon dots/TiO2 nanocomposites for the photocatalytic color switching system.

In view of the easy control and contactless spatial nature of light, the photoreversible color switching system has attracted tremendous attention. Although some progress has been achieved in the past few years, the practical applications have been limited by the complicated preparation process, material toxicity and low reaction yield. Herein, we report a rapid, a one-pot large-scale synthesis approach for the preparation of carbon dots (CDs)/TiO2 nanocomposites via the thermal condensation at 160 °C, affording high photocatalytic color switching on/off performance. Under ambient conditions and with the introduction of some oxygen gas, MB rapidly changed from blue to colorless in one minute under UV-vis irradiation and recovered (again showed its original blue color) in twenty minutes. We anticipate that the designed low-cost and green carbon dots (CDs)/TiO2 nanocomposites have much potential in practical applications and represent a solid step toward color switching applications.

Multicolor Tuning and Temperature-Triggered Anomalous Eu3+-Related Photoemission Enhancement via Interplay of Accelerated Energy Transfer and Release of Defect-Trapped Electrons in the Tb3+,Eu3+-Doped Strontium-Aluminum Chlorites.

So far, a large number of rare earth (RE) and non-RE-doped emission-tunable crystals based on controllable energy transfer have become available, but numerous mechanistic issues, particularly for those that involve temperature-dependent energy transfer between the well-shielded 4f RE ions, lack comprehensive theoretical and experimental investigation, limiting greatly their development and applications in the future. Here, we design and report a type of Tb3+,Eu3+-doped Sr3Al2O5Cl2 phosphors capable of multiemissions upon excitation at 376 nm, through using the orthorhombic Sr3Al2O5Cl2 as the host lattice while the well-shielded 4f Tb3+ and Eu3+ ions as dual luminescent centers. Our results reveal that the energy transfer from Tb3+ to Eu3+ ions, happening via an electric dipole-quadrupole (d-q) interaction, can be controlled by the doping ratio of Tb3+ and Eu3+, leading to the tunable emissions from green (0.3159, 0.5572) to red (0.6579, 0.3046). It is found from time-resolved photoluminescence (PL) spectra that this energy transfer begins at t = 5 µs and gradually ends at t ≥ 200 µs. Moreover, from temperature-dependent PL results, we reveal that the Eu3+ emission features an anomalous intensity enhancement at the earlier heating state. With the density functional theory (DFT) calculations, we have screened the possibilities of site preferential substitution problem. By jointly taking into account the X-ray diffraction Rietveld refinement, DFT findings, and PL and thermoluminescence spectra, a mechanistic profile is proposed for illustrating the PL observations. In particular, our discussions reveal that the temperature-triggered Eu3+ emission enhancement is due to the interplay of the temperature-induced accelerated energy transfer and defect-trapped electrons that are released upon the thermal stimulation. Unlike most of reported phosphor materials that are always suggested for phosphor-converted white light-emitting diodes, we propose new application possibilities for Tb3+,Eu3+-doped Sr3Al2O5Cl2 phosphors, such as anticounterfeiting, temperature-controlled fluorescence sensor, data storage, and security devices.

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensing.

Graphene-embedded plant tissues show a high sensitivity to electrochemical signals, which enables a screen-printed electrode to be used for electrochemical fingerprint recording. The electrochemical fingerprints obtained under different conditions can be transformed into multidimensional recognition modes for plant identification. These electrochemical fingerprints reflect the types and quantities of the electrochemically active substances in plant tissues such that the fingerprints can be used for chemotaxonomic investigations. In this paper, five species of Lycoris bulbs, including L. chinensis, L. radiate, L. aurea, L. sprengeri and L. straminea, were successfully recognized by electrochemical fingerprinting. The species's interspecific relationships were also investigated. L. chinensis and L. aurea show highly similar morphology but have a relatively distant relationship. Hybridized L. radiata shows a notably close relationship with L. straminea, suggesting that one of its parents may be L. radiata. In addition, L. chinensis also shows a close relationship with L. straminea, suggesting that the L. straminea may be produced by cross-breeding L. chinensis and L. radiate. The results mentioned above indicate that the proposed electro-chemotaxonomic methodology is an inexpensive and quick taxonomic method that can provide additional evidence for the existing taxonomy system.

A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and paracetamol.

Nitrogen doped carbon dots (NCDs) were synthesized using a low temperature approach and used to modify a glassy carbon electrode (GCE) via dipping. The oxygen groups on the surface of the NCDs, and the charge delocalization of the NCDs warrant an excellent electrocatalytic activity of the GCE toward oxidation of paracetamol (PA) and reduction of H2O2. PA and H2O2 were detected at 0.34 V and -0.4 V (both vs. Ag/AgCl) using differential pulse voltammetry and amperometric I-T measurement, respectively. The modified GCE has a linear response to PA in the 0.5 to 600 µM concentration range, and to H2O2 in the 0.05 µM to 2.25 mM concentration range. The detection limits are 157 nM and 41 nM, respectively. In our perception, the modified GCE holds promise for stable, selective and sensitive determination of PA and H2O2 in pharmaceutical analysis. Graphic abstract Nitrogen doped carbon dots (NCDs) were synthesized and used to modify a glassy carbon electrode. Surface functional groups on NCDs can trigger electrocatalytic reactions toward paracetamol oxidation and H2O2 reduction with high sensitivities.

Electrochemical antioxidant screening based on a chitosan hydrogel.

A chitosan based hydrogel has been fabricated using silver ions as crosslinking agent. Silver redox behavior in the hydrogel is suppressed due to complexation. However, hydrogen peroxide induced hydroxyl radicals could attract the glucoside bonds and consequently restore silver redox behavior. Therefore, we used this hydroxyl radical induced chitos and epolymerization mechanism as an indicator for antioxidant capacity evaluation. Therefore, we used this hydroxyl radical induced chitos and epolymerization as an indicator for antioxidant capacity evaluation. Due to the low cost, portability and avoidance of the need for electrode modification, we believe the proposed hydrogel sensing platform shows great potential for antioxidant screening applications.

Defects regulating of graphene ink for electrochemical determination of ascorbic acid, dopamine and uric acid.

A simple water immersing treatment has been established for regulating the electrocatalytic activity of commercial graphene ink. This process enables to remove additives in graphene ink and consequently expose the surface defects. A graphene ink coated glass has been fabricated as an example platform for simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Cyclic voltammetry studied indicated electrocatalytic reaction can be initiated after the additives leaching during the water immersing treatment. Under optimal conditions, the linear calibration curves were achieved in the range of 50-1000, 3-140, and 0.5-150µM, with detection limits of 17.8, 1.44 and 0.29µM for AA, DA, and UA, respectively. This work demonstrated that the removal of additives of the graphene ink after film coating could be applied as a simple and cost-effective electrochemical platform for sensing application.

Recent Advances of Graphitic Carbon Nitride-Based Structures and Applications in Catalyst, Sensing, Imaging, and LEDs.

The graphitic carbon nitride (g-C3N4) which is a two-dimensional conjugated polymer has drawn broad interdisciplinary attention as a low-cost, metal-free, and visible-light-responsive photocatalyst in the area of environmental remediation. The g-C3N4-based materials have excellent electronic band structures, electron-rich properties, basic surface functionalities, high physicochemical stabilities and are "earth-abundant." This review summarizes the latest progress related to the design and construction of g-C3N4-based materials and their applications including catalysis, sensing, imaging, and white-light-emitting diodes. An outlook on possible further developments in g-C3N4-based research for emerging properties and applications is also included.

Hydrothermal preparation of reduced graphene oxide-silver nanocomposite using Plectranthus amboinicus leaf extract and its electrochemical performance.

Graphene based nanocomposites are receiving increasing attention in many fields such as material chemistry, environmental science and pharmaceutical science. In this study, a facial synthesis of a reduced graphene oxide-silver nanocomposite (RGO-Ag) was carried out from Plectranthus amboinicus leaf extract. The synthesized nanocomposite was characterized by using X-ray diffraction, scanning electron microscope, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscope and UV-vis spectroscopy for structural confirmation. The reduction of graphene oxide and silver ions was achieved simultaneously due to the reducibility of the Plectranthus amboinicus leaf extract. We further investigated the electrochemical properties of the biosynthesized RGO-Ag nanocomposite. A nonenzymatic H2O2 electrochemical sensor was shown to be successfully fabricated by using biosynthesized RGO-Ag nanocomposite. Moreover, the fabricated electrochemical sensor also showed good selectivity.

Perovskite Photovoltachromic Supercapacitor with All-Transparent Electrodes.

Photovoltachromic cells (PVCCs) are of great interest for the self-powered smart windows of architectures and vehicles, which require widely tunable transmittance and automatic color change under photostimuli. Organolead halide perovskite possesses high light absorption coefficient and enables thin and semitransparent photovoltaic device. In this work, we demonstrate co-anode and co-cathode photovoltachromic supercapacitors (PVCSs) by vertically integrating a perovskite solar cell (PSC) with MoO3/Au/MoO3 transparent electrode and electrochromic supercapacitor. The PVCSs provide a seamless integration of energy harvesting/storage device, automatic and wide color tunability, and enhanced photostability of PSCs. Compared with conventional PVCC, the counter electrodes of our PVCSs provide sufficient balancing charge, eliminate the necessity of reverse bias voltage for bleaching the device, and realize reasonable in situ energy storage. The color states of PVCSs not only indicate the amount of energy stored and energy consumed in real time, but also enhance the photostability of photovoltaic component by preventing its long-time photoexposure under fully charged state of PVCSs. This work designs PVCS devices for multifunctional smart window applications commonly made of glass.

[Preparation and clinical observation of Koukuining granules in 50 patients with recurrent aphthous ulcer].

PURPOSE: To prepare Koukuining granules and observe its efficiency in the treatment of recurrent aphthas ulce (RAU). METHODS: In accordance with the theories of traditional Chinese medicine, the prescriptions of Koukuining granules were composed of rhizoma coptidis, radix scutellariae and other Chinese herbs, and the preparation procedure was conducted by means of wet granulation technology. One hundred patients with RAU were randomly divided into experimental group and control group equally. Patients in the experimental group took particles orally after a meal, 3 times a day, 1 bag each time, for successive 10 days as one treatment course. The treatment was repeated after 3 days of interval. Patients in the control group took vitamin C, compound vitamin B2, orally for 2 courses. The treatment effect was evaluated. Data analysis was performed using SPSS 11.5 software package. RESULTS: The preparation process was controllable and the quality of the products was stable. The overall effective rate of the experimental group was 88.4% and there was a significant difference compared with the control group. CONCLUSIONS: The preparation of Koukuining granules was feasible with stable quality of final products. Treatment of RAU with the granules was effective and worthy of clinical application.

Sensitive determination of quinoline yellow using poly (diallyldimethylammonium chloride) functionalized reduced graphene oxide modified grassy carbon electrode.

A novel poly (diallyldimethylammonium chloride) functionalized reduced graphene oxide (PDDA-RGO) nanocomposite modified electrode was fabricated, and applied for the electrochemical determination of quinoline yellow (QY). The formation of PDDA-RGO nanocomposite was confirmed by SEM, FTIR and Raman spectroscopy. The electrocatalytic activity of PDDA-RGO nanocomposite to the oxidation of QY was evaluated using cyclic voltammetry and differential pulse voltammetry. Under the optimal conditions, the proposed sensor exhibited excellent electrochemical performance towards detection of QY. The linear range is from 0.01 to 10 µM, and the detection limit is down to 0.002 µM (S/N=3). The proposed sensor also exhibited excellent anti-interference property, repeatability and stability. In addition, the proposed electrochemical sensor was successfully applied to determination of QY in soft drink.

Baicalein attenuates angiotensin II-induced cardiac remodeling via inhibition of AKT/mTOR, ERK1/2, NF-κB, and calcineurin signaling pathways in mice.

BACKGROUND: Baicalein, a specific lipoxygenase (LOX) inhibitor, has anti-inflammatory and antioxidant effects. However, the functional role of baicalein in angiotensin II (Ang II)-induced hypertension and cardiac remodeling remains unclear. Here we investigated the effect of baicalein on cardiac hypertrophy and fibrosis and the underlying mechanism. METHODS: Wild-type (WT) mice were injected with Ang II (1,200ng/kg/min) alone or together with 12/15-LOX inhibitor baicalein (25mg/kg) for 14 days. Histological examinations were performed on heart sections with hematoxylin and eosin, Masson's trichrome, wheat germ agglutinin staining, and immunohistochemistry. The messenger RNA (mRNA) expression of cytokines and protein levels were detected by real-time polymerase chain reaction (PCR) and western blot analysis respectively. RESULTS: Ang II infusion significantly increased blood pressure but decreased cardiac contractile function reflected by fractional shortening% and ejection fraction% compared with saline-treated mice. Moreover, Ang II infusion resulted in marked cardiac hypertrophy and fibrosis, promoted accumulation of macrophages and T cells, the expression of proinflammatory cytokines and malondialdehyde (MDA) production. However, these actions were markedly reversed by administration of baicalein in mice. Mechanistically, the protective effects of baicalein were associated with the inhibition of inflammation, oxidative stress, and multiple signaling pathways (AKT/mTOR, ERK1/2, nuclear factor-κB (NF-κB), and calcineurin) in the Ang II-treated mice. CONCLUSIONS: This study demonstrates that baicalein can significantly ameliorate Ang II-induced hypertension and cardiac remodeling, and may be a novel therapeutic drug for prevention of hypertensive heart diseases.