Theoretical simulation of the reduction of graphene oxide by lithium naphthalenide.

Based on density functional theory, we investigated the mechanism of graphene oxide reduction by lithium naphthalenide (C10H8Li). C10H8(-) easily reacts with GO to form a neutral C10H8 and the negatively charged GO, which can attach to Li(+) ions to form lithium oxide on a graphene skeleton. The reduction mechanism is similar to the reduction of GO by metallic Li; the C10H8 is used to disperse Li in THF solution. Furthermore, the lithium oxide on GO can react with CO2 to form Li2CO3 and be further reduced by MeOH washing. In the negatively charged GO, the carboxyl at the edge of GO transfers an electron to GO and releases a CO2 molecule by overcoming a barrier of 0.19 eV. CO2 can also be adsorbed by lithium oxide to form Li2CO3 that is tightly attached on graphene skeleton. After GO is partially reduced, the adsorption of CO2 eliminates O in the form of Li2CO3 without any barrier. This mechanism can be helpful for further understanding the nature of GO reduction among various reducing agents and for exploring new and efficient GO reducing agents.

Airway microbiota in children with bronchial mucus plugs caused by Mycoplasma pneumoniae pneumonia.

BACKGROUND: There is increasing evidence for a role of lung microbiota in the pathogenesis of Mycoplasma pneumoniae pneumonia (MPP). However, the alterations of lung microbiota in MPP with bronchial mucus plugs and its role in disease pathogenesis remain poorly understood. METHODS: In this prospective observational study, we performed a longitudinal 16S rRNA-based microbiome survey on bronchoalveolar lavage (BAL) samples collected from 31 MPP with bronchial mucus plugs and 52 MPP without mucus plugs. RESULTS: Our study showed a clear difference in airway microbiota between MPP children with and without bronchial mucus plugs. The MPP children with mucus plugs had lower abundances of Sphingomonas and Elizabethkingia, and a high abundance of Mycoplasma compared with MPP children without mucus plugs, subsequently contributing to increased ratios of Mycoplasma to Sphingomonas and Mycoplasma to Elizabethkingia. Children's age, fever time and serum cytokine levels were associated with airway microbiota alteration. Furthermore, significant correlations between bacterial genus abundances were found in MPP children with mucus plugs. CONCLUSIONS: Our results suggest an impact of airway microbiota on the clinical course of MPP in children, deserving further investigations.

Biomarkers of intravenous immunoglobulin resistance and coronary artery lesions in Kawasaki disease.

BACKGROUND: Currently, there are no reliable indicators for predicting intravenous immunoglobulin resistance and coronary artery lesions in the early stage of Kawasaki disease. METHODS: A total of 300 patients with Kawasaki disease were studied retrospectively. Laboratory data were compared between the intravenous immunoglobulin resistant (29 patients) and responsive groups, and between the groups with coronary artery lesions (48 patients) and without coronary artery lesions. RESULTS: The intravenous immunoglobulin resistant group had significantly higher D-dimer, globulin, interleukin-6 and serum ferritin levels in comparison to the intravenous immunoglobulin responder group. D-dimer level had a sensitivity of 87.0% and a specificity of 56.3% for predicting intravenous immunoglobulin resistance at a cutoff point of 1.09 mg/L. Globulin had a sensitivity of 62.1% and a specificity of 82.3% for predicting intravenous immunoglobulin resistance at a cutoff point of 34.7 g/L. Serum ferritin level had a sensitivity of 42.9% and a specificity of 88.8% for predicting intravenous immunoglobulin resistance at a cutoff point of 269.7 ng/mL. The patients with coronary artery lesions had higher D-dimer and tumor necrosis factor-α level. D-dimer level had a sensitivity of 50% and a specificity of 78.6% for predicting coronary artery lesions at a cutoff point of 1.84 mg/L. Based on analysis by multivariate logistic regression, serum ferritin and globulin were independent risks for intravenous immunoglobulin resistance, D-dimer was independent risk for coronary artery lesions. CONCLUSIONS: Elevated serum ferritin, globulin and D-dimer levels are significantly associated with intravenous immunoglobulin resistance in Kawasaki disease. Moreover, serum D-dimer is significantly increased in Kawasaki disease with coronary artery lesions.