Morning Glory Syndrome With Bergmeister Papilla and Retinal Detachment.

This case report discusses a diagnosis of morning glory syndrome and concurrent Bergmeister papilla and retinal detachment in a child aged 3 years.

Fluorescence Characteristics of Aqueous Synthesized Tin Oxide Quantum Dots for the Detection of Heavy Metal Ions in Contaminated Water.

Tin oxide quantum dots were synthesized in aqueous solution via a simple hydrolysis and oxidation process. The morphology observation showed that the quantum dots had an average grain size of 2.23 nm. The rutile phase SnO2 was confirmed by the structural and compositional characterization. The fluorescence spectroscopy of quantum dots was used to detect the heavy metal ions of Cd2+, Fe3+, Ni2+ and Pb2+, which caused the quenching effect of photoluminescence. The quantum dots showed the response of 2.48 to 100 ppm Ni2+. The prepared SnO2 quantum dots exhibited prospective in the detection of heavy metal ions in contaminated water, including deionized water, deionized water with Fe3+, reclaimed water and sea water. The limit of detection was as low as 0.01 ppm for Ni2+ detection. The first principle calculation based on the density function theory demonstrated the dependence of fluorescence response on the adsorption energy of heavy metal ions as well as ion radius. The mechanism of fluorescence response was discussed based on the interaction between Sn vacancies and Ni2+ ions. A linear correlation of fluorescence emission intensity against Ni2+ concentration was obtained in the logarithmic coordinates. The density of active Sn vacancies was the crucial factor that determined fluorescence response of SnO2 QDs to heavy metal ions.

Preparation of Tin Oxide Quantum Dots in Aqueous Solution and Applications in Semiconductor Gas Sensors.

Tin oxide quantum dots (QDs) were prepared in aqueous solution from the precursor of tin dichloride via a simple process of hydrolysis and oxidation. The average grain size of QDs was 1.9 nm. The hydrothermal treatment was used to control the average grain size, which increased to 2.7 and 4.0 nm when the operating temperatures of 125 and 225 °C were employed, respectively. The X-ray photoelectron spectroscopy (XPS) spectrum and X-ray diffraction analysis (XRD) pattern confirmed a rutile SnO2 system for the QDs. A band gap of 3.66 eV was evaluated from the UV-VIS absorption spectrum. A fluorescence emission peak was observed at a wavelength of 300 nm, and the response was quenched by the high concentration of QDs in the aqueous solution. The current-voltage (I-V) correlation inferred that grain boundaries had the electrical characteristics of the Schottky barrier. The response of the QD thin film to H2 gas revealed its potential application in semiconductor gas sensors.

Influence of Oxygen Vacancy Behaviors in Cooling Process on Semiconductor Gas Sensors: A Numerical Analysis.

The influence of oxygen vacancy behaviors during a cooling process in semiconductor gas sensors is discussed by the numerical analysis method based on the gradient-distributed oxygen vacancy model. A diffusion equation is established to describe the behaviors of oxygen vacancies, which follows the effects of diffusion and exclusion in the cooling process. Numerical analysis is introduced to find the accurate solutions of the diffusion equation. The solutions illustrate the oxygen vacancy distribution profiles, which are dependent on the cooling rate as well as the temperature interval of the cooling process. The gas-sensing characteristics of reduced resistance and response are calculated. Both of them, together with oxygen vacancy distribution, show the grain size effects and the re-annealing effect. It is found that the properties of gas sensors can be controlled or adjusted by the designed cooling process. The proposed model provides a possibility for sensor characteristics simulations, which may be beneficial for the design of gas sensors. A quantitative interpretation on the gas-sensing mechanism of semiconductors has been contributed.

Artesunate Attenuates Pro-Inflammatory Cytokine Release from Macrophages by Inhibiting TLR4-Mediated Autophagic Activation via the TRAF6-Beclin1-PI3KC3 Pathway.

BACKGROUND/AIMS: Lipopolysaccharide (LPS) plays a critical role in excessive inflammatory cytokine production during sepsis. Previously, artesunate (AS) was reported to protect septic mice by reducing LPS-induced pro-inflammatory cytokine release. In the present study, the possible mechanism of the anti-inflammatory effect of AS was further investigated. METHODS: An enzyme-linked immunosorbent assay was used to detect TNF-α and IL-6 release from macrophages. Specific small interfering RNAs (siRNAs) were used to knockdown the mRNA expression of target genes. Transmission electron microscopy and laser confocal microscopy were used to observe changes in autophagy. Western blotting was performed to detect the protein levels of tumor necrosis factor receptor-associated factor6 (TRAF6), Beclin1, phosphatidylinositol 3-kinase class III (PI3KC3), autophagy-related protein 5 (ATG5), and sequestosome 1. Immunoprecipitation (IP) and fluorescent co-localization were used to detect the interactions between TRAF6-Beclin1 and Beclin1-PI3KC3, and the ubiquitination of Beclin1. RESULTS: AS inhibited TNF-α and IL-6 release from RAW264.7 cells, mouse bone marrow-derived monocytes (BMDMs) and peritoneal macrophages (PMs) induced by LPS. However, the inhibition by AS of LPS-induced cytokine release decreased when autophagy was inhibited using 3-MA, bafilomycin A1, or a siRNA targeting the Atg5 gene. Notably, AS showed an inhibition of LPS-induced autophagic activation not degradation. Whereas, these effects of AS were lost in macrophages lacking TLR4 and decreased in macrophages with down-regulated TRAF6, indicating that AS inhibited LPS-induced cytokine release and autophagic activation via TLR4-TRAF6 signaling. Western blotting results showed AS could reduce the levels of TRAF6, Beclin1, and PI3KC3. Importantly, the IP results showed AS only inhibited K63-linked ubiquitylation not total ubiquitylation of Beclin1 by acting on TRAF6. This interrupted the TRAF6-Beclin1 interaction and subsequent the formation of Beclin1- PI3KC3 core complex of the PI3K-III complex. CONCLUSION: AS inhibited LPS-induced cytokine release from macrophages by inhibiting autophagic activation. This effect was tightly related to blockade of the TRAF6-Beclin1-PI3KC3 pathway via decreasing K63-linked ubiquitination of Beclin1 and then interrupting the formation of Beclin1-PI3KC3 core complex of the PI3K-III complex. Our findings reveal the mechanism of AS's anti-inflammatory effect and is significant for future targeted investigations of sepsis treatment.

Inhomogeneous Oxygen Vacancy Distribution in Semiconductor Gas Sensors: Formation, Migration and Determination on Gas Sensing Characteristics.

The density of oxygen vacancies in semiconductor gas sensors was often assumed to be identical throughout the grain in the numerical discussion of the gas-sensing mechanism of the devices. In contrast, the actual devices had grains with inhomogeneous distribution of oxygen vacancy under non-ideal conditions. This conflict between reality and discussion drove us to study the formation and migration of the oxygen defects in semiconductor grains. A model of the gradient-distributed oxygen vacancy was proposed based on the effects of cooling rate and re-annealing on semiconductive thin films. The model established the diffusion equations of oxygen vacancy according to the defect kinetics of diffusion and exclusion. We described that the steady-state and transient-state oxygen vacancy distributions, which were used to calculate the gas-sensing characteristics of the sensor resistance and response to reducing gases under two different conditions. The gradient-distributed oxygen vacancy model had the applications in simulating the sensor performances, such as the power law, the grain size effect and the effect of depletion layer width.

Systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model and their characteristics.

Immunosuppression is involved in refractory innate and adaptive immune responses and is considered to be the predominant driving force for mortality in sepsis. The cecal ligation and puncture (CLP) model is regarded as a golden standard model for sepsis study, but the turning point of over-inflammation to immunosuppression was reported differently. Herein, systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model was carried out. The results showed only the mortality of mice challenged with of Pseudomonas aeruginosa on Day 1 not other days after the surgery was higher than that of other mice with Sham surgery, suggesting Day 1 after the CLP surgery might be the turning point. There was very low mortality even without death in Sham mice but the mortality was 80% after mice were challenged with 2.5×107, 5.0×106 and 1.0×106CFU/10g of Pseudomonas aeruginosa, further demonstrating Day 1 after the CLP surgery was the turning point. And, CLP mice presented low levels of pro-inflammatory and anti-inflammatory cytokines, and high bacterial loads on Day 1. Additionally, the amounts and proportion of blood cells and monocytes significantly changed, too. In conclusion, Day 1 after the CLP surgery was the turning point of over-inflammation to immunosuppression, and low levels of cytokines and high bacterial loads were the characteristics of this model on Day 1, which is significant for pharmacological investigation on sepsis.

Design of New Antibacterial Enhancers Based on AcrB's Structure and the Evaluation of Their Antibacterial Enhancement Activity.

Previously, artesunate (AS) and dihydroartemisinine 7 (DHA7) were found to have antibacterial enhancement activity against Escherichia coli via inhibition of the efflux pump AcrB. However, they were only effective against E. coli standard strains. This study aimed to develop effective antibacterial enhancers based on the previous work. Our results demonstrate that 86 new antibacterial enhancers were designed via 3D-SAR and molecular docking. Among them, DHA27 had the best antibacterial enhancement activity. It could potentiate the antibacterial effects of ampicillin against not only E. coli standard strain but also clinical strains, and of ß-lactam antibiotics, not non-ß-lactamantibiotics. DHA27 could increase the accumulation of daunomycin and nile red within E. coli ATCC 35218, but did not increase the bacterial membrane permeability. DHA27 reduced acrB's mRNA expression of E. coli ATCC 35218 in a dose-dependent manner, and its antibacterial enhancement activity is related to the degree of acrB mRNA expression in E. coli clinical strains. The polypeptides from AcrB were obtained via molecular docking assay; the pre-incubated polypeptides could inhibit the activity of DHA27. Importantly, DHA27 had no cytotoxicity on cell proliferation. In conclusion, among newly designed antibacterial enhancers, DHA27 had favorable physical and pharmacological properties with no significant cytotoxicity at effective concentrations, and might serve as a potential efflux pump inhibitor in the future.