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OBJECTIVE: This study investigated the relationship between the glucocorticoid-induced transcript 1 (GLCCI1) gene variant and the degree of improvement in lung function with inhaled corticosteroids (ICS). METHODS: We searched the PubMed, Embase, Cochrane Library, CBM, CNKI and Wanfang databases to obtain studies on the GLCCI1 rs37973 variant and the efficacy of ICS in asthma. RESULTS: The overall meta-analysis showed that patients with the GG phenotype (mutant homozygotes) exhibited significantly smaller forced expiratory volume in 1 sec (FEV1) change than patients with the AG phenotype (mutant heterozygous) (MD = -0.08, 95% CI [-0.12, -0.03], P = 0.001). Compared with the AA phenotype (wild homozygotes), the GG phenotype (MD = -4.23, 95% CI [-6.09, -2.38], P < 0.00001) and AG phenotype (MD = -1.92, 95% CI [-2.35, -1.49], P < 0.00001) had significantly smaller FEV1%pred changes. The FEV1 change subgroup analysis showed that the GG phenotype group was smaller than the AA phenotype group at 8 (MD = -0.53, 95% CI [-0.91, -0.14], P = 0.007), 12 (MD = -0.16, 95% CI [-0.30, -0.02], P = 0.02) and 24 (MD = -0.09, 95% CI [-0.17, -0.01], P = 0.02) weeks of treatment; the GG phenotype group was smaller than the AG phenotype group at 12 weeks (MD = -0.08, 95% CI [-0.15, -0.01], P = 0.02). CONCLUSION: This meta-analysis suggests that the GLCCI1 rs37973 variant affects the efficacy of ICS and that the presence of the G allele attenuates the improvement in lung function with ICS.

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Both sulfuric acid (H2SO4) and nitrous oxide (N2O) play a central role in the atmospheric chemistry in regulating the global environment and climate changes. In this study, the interaction behavior between H2SO4 and N2O before and after electron capture has been explored using the density functional theory (DFT) method as well as molecular dynamics simulation. The intermolecular interactions have been characterized by atoms in molecules (AIM), natural bond orbital (NBO), and reduced density gradient (RDG) analyses, respectively. It was found that H2SO4 and N2O can form two transient molecular complexes via intermolecular H-bonds within a certain timescale. However, two molecular complexes can be transformed into OH radical, N2, and HSO4- species upon electron capture, providing an alternative formation source of OH radical in the atmosphere. Expectedly, the present findings not only can provide new insights into the transformation behavior of H2SO4 and N2O, but also can enable us to better understand the potential role of the free electron in driving the proceeding of the relevant reactions in the atmosphere.

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Dissociative electron attachment (DEA) processes of six low-lying conformers (1-6) of dialanine in the gas phase are investigated by using ab initio molecular dynamics simulations. The incoming electron is captured and primarily occupies the virtual molecular orbital π*, which is followed by the different dissociation processes. The electron attachments to conformers 1 and 2 having the stronger N-H···N and O-H···O intramolecular hydrogen bonds do not lead to fragmentations, but two different backbone bonds are broken in the DEAs to conformers 3 (or 4) and 6, respectively. It is interesting that the hydrogen abstraction of -NH from the terminal methyl group -CH3 is found in the roaming dissociation of the temporary anion of conformer 3. The present simulations enable us to have more insights into the peptide backbone bond breaks in the DEA process and demonstrate a promising way toward understanding of the radiation damages of complicated biological system.

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Dissociation dynamics of the temporary negative ions of ethanol and acetaldehyde formed by the low-energy electron attachments is investigated by using the anion velocity map imaging technique and ab initio molecular dynamics simulations. The momentum images of the dominant fragments O(-)/OH(-) and CH3 (-) are recorded, indicating the low kinetic energies of O(-)/OH(-) for ethanol while the low and high kinetic energy distributions of O(-) ions for acetaldehyde. The CH3 (-) image for acetaldehyde also shows the low kinetic energy. With help of the dynamics simulations, the fragmentation processes are qualitatively clarified. A new cascade dissociation pathway to produce the slow O(-) ion via the dehydrogenated intermediate, CH3CHO(-) (acetaldehyde anion), is proposed for the dissociative electron attachment to ethanol. After the electron attachment to acetaldehyde molecule, the slow CH3 (-) is produced quickly in the two-body dissociation with the internal energy redistributions in different aspects before bond cleavages.

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This study was set to introduce a new intramedullary fixation, explore its biomechanical properties, and provide guidance for further biomechanical experiments. With the help of CT scans and finite element modeling software, finite element model was established for a new intramedullary fixation and intramedullary nailing of femoral shaft fractures in a volunteer adult. By finite element analysis software ANSYS 10.0, we conducted 235-2,100 N axial load, 200-1,000 N bending loads and 2-15 Nm torsional loading, respectively, and analyzed maximum stress distribution, size, and displacement of the fracture fragments of the femur and intramedullary nail. During the loading process, the maximum stress of our new intramedullary fixation were within the normal range, and the displacement of the fracture fragments was less than 1 mm. Our new intramedullary fixation exhibited mechanical reliability and unique advantages of anti-rotation, which provides effective supports during fracture recovery.

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