Co3O4 particles grown over nanocrystalline CeO2: influence of precipitation agents and calcination temperature on the catalytic activity for methane oxidation

Crystalline cobalt oxides were prepared by a precipitation method using three different precipitation agents, (NH₄)₂CO₃, Na₂CO₃ and CO(NH₂)₂.

Giant delayed pseudo-aneurysm following screw placement in C1 lateral mass

We report the case of a patient who suffered iatrogenic vertebral artery injury (VAI) during a cervical spine posterior fixation procedure. The patient suffered massive bleeding and hemorrhagic shock at the time of screws placement in C1 lateral mass and C2 pedicle. The postoperative MRI and CT angiography showed a pseudoaneurysm 7.0 cm in diameter in the cervical spine. The iatrogenic VAI during posterior screw fixation is extremely rare. But, it can cause catastrophic consequences. We discuss the causes for the iatrogenic VAI and review the preventative measures and suitable management to avoid iatrogenic complications.

Synergistic antitumor effect of α-pinene and β-pinene with paclitaxel against non-small-cell lung carcinoma (NSCLC)

The objective of the present research work was to evaluate the synergistic interactions between Paclitaxel (PAC) with α-pinene and β-pinene using isobolographic method against non-small-cell lung cancer cells (NSCLC). This type of interaction between an established drug and a new compound is expected to enhance the efficacy of paclitaxel in combination as compared in isolation. Further, cell cycle analysis was carried out using flow cytometric analysis. Phase contrast microscopy was used to assess the effect of paclitaxel, α-pinene and β-pinene alone and in combination with each other in order to evaluate the effect of combination on cell apoptosis. Further, mitochondrial membrane potential was monitored in non-small-cell lung cancer cells (NSCLC) when treated with paclitaxel, α-pinene and β-pinene alone and in combination. The results revealed that the combination of PAC with α-pinene or with β-pinene showed a plotted curve below the straight line, generating a substantial synergistic effect. The effects of the following combinations were examined utilizing isobolograms: PAC and α-pinene and PAC and β-pinene. The combination of PAC and α-pinene as well as of PAC and β-pinene actually generated a synergistic effect. We also examined the effects of these compounds on the cell cycle distributions of A549 cells by flow cytometric analysis. The percentage of sub-G0/G1-phase cells was decreased on the addition of α-pinene to PAC, while the population of G0/G1 cells was increased. The morphological changes characteristic of apoptosis like chromatin condensation and fragmentation of the nucleus were seen in PAC+α-pinene and PAC+β-pinene treated NSCLC cells.

Effect of diclofenac on the pharmacokinetics of moxifloxacin in rats

A sensitive and specific method was developed and validated for the determination of moxifloxacin in plasma using HPLC. The effect of diclofenac (12.5, 25, 50 mg/kg) on the pharmacokinetics of orally administered moxifloxacin (40 mg/kg) in rats was investigated. Pharmacokinetic parameters of moxifloxacin were determined in rats following oral administration to rats in the presence and absence of diclofenac. The coadministration of the 2 drugs resulted in 10~29.5% decrease of the AUC and a 24.7~34% decrease of t1/2 for moxifloxacin; Tmax for moxifloxacin was 1.41~1.9-fold higher than that after the administration of moxifloxacin alone; Cmax for moxifloxacin decreased by 20.5~49%, as compared to that after the administration of moxifloxacin alone. Consequently, moxifloxacin and diclofenac should be monitored closely for potential drug interactions.

Design of broadband omnidirectional antireflection coatings using ant colony algorithm

Optimization method which is based on the ant colony algorithm (ACA) is described to optimize antireflection (AR) coating system with broadband omnidirectional characteristics for silicon solar cells incorporated with the solar spectrum (AM1.5 radiation). It's the first time to use ACA method for optimizing the AR coating system. In this paper, for the wavelength range from 400 nm to 1100 nm, the optimized three-layer AR coating system could provide an average reflectance of 2.98% for incident angles from Raveθ+ to 80° and 6.56% for incident angles from 0° to 90°.

Increased oxidative stress and activated heat shock proteins in human cell lines by silver nanoparticles

Due to widely commercial applications of silver nanoparticles (Ag NPs), toxicity assessment of this NP is of great importance. This study aimed to investigate the oxidative stress and heat shock response of Ag NPs at different doses to A549 and HepG2 cells. After treatment with different concentrations of Ag NPs for 24 h, oxidative damage indicated by malondialdehyde (MDA), 8-epi-PGF2α, and 8-hydroxy-2'-deoxyguanosine (8-oxo-dG) concentrations and protein levels of heat shock protein A1A (HSPA1A) and heme oxygenase 1 (HO-1) were determined. Ag NPs induced dose-dependent increases in MDA, 8-epi-PGF2α, and 8-oxo-dG concentrations in both A549 and HepG2 cells. Stress-inducible HSPA1A and HO-1 were also significantly upregulated in a dose-dependent manner. A higher level of HSPA1A and HO-1 activation by Ag NPs occurred in HepG2 cells than that in A549 cells. Compared with that of HSPA1A, Ag NPs induced a stronger increase in protein level of HO-1 in both cell lines. Significant positive correlations between protein levels of HSPA1A and HO-1 and oxidative damage were also observed. In conclusion, Ag NPs could induce oxidative stress in human cell lines. In addition to the products of oxidative stress such as MDA and 8-oxo-dG, HSPs can be used as potential biomarkers in nanotoxicity assessment, especially HO-1.

Improved Interfacial Properties of PA6/DE Blends by DE-g-MAH Prepared through Ultrasound Assisted Extrusion

In this paper, ultrasound was applied in extrusion reaction processing to graft an Elastomer (DE) with maleic anhydride (MAH), in order to improve the non-polarity of DE. Two types of DE-g-MAH were prepared by different methods and had similar grafting degree about 0.2 % and then they were added into the polyamide-6/elastomer (PA6/DE) blends, respectively. The effect of DE-g-MAH on the interfacial properties of PA6/DE blends was studied. The experimental results showed that, compared to the DE-g-MAH initiated by peroxide, DE-g-MAH initiated by ultrasound had better effect on refining the particle size of the dispersion phase and keeping the stability of the phase in the blends, which could be confirmed through SEM and Molau tests. When 5 % DE-g-MAH initiated by peroxide was added, the particle size of dispersion phase was 3.90 μm, however, when 5 % DE-g-MAH initiated by ultrasound was added, the particle size of dispersion phase was 2.82 μm. The results of TGA and mechanical tests showed the improved interfacial interaction and enhanced interfacial adhesion of the blend by adding DE-g-MAH, respectively.

Long-term outcomes after nucleos(t)ide analogue discontinuation in HBeAg-positive chronic hepatitis B patients

Nucleos(t)ide analogue (NUC) resistance is an important clinical risk resulting from long-term therapy in chronic hepatitis B (CHB) management. Discontinuation of NUCs is a feasible strategy to reduce resistance. We aimed to observe the outcomes after NUC withdrawal in HBeAg-positive CHB patients. A total of 97 patients (11 patients with HBsAg loss and 86 patients with sustained HBeAg seroconversion) were enrolled. HBV DNA levels and alanine aminotransferase (ALT) levels were monitored regularly after discontinuation. Relapse was defined as HBV DNA levels >2000 IU/mL in at least two determinations more than 4 weeks apart. HBeAg seroconversion was achieved within 48 weeks (interquartile range (IQR), 24-72 weeks). The time on consolidation therapy was 96 weeks (IQR, 84-144 weeks). No relapses occurred for HBsAg loss patients. Evidence of relapse was observed in 9.3% of HBeAg seroconversion patients. All relapse cases occurred within 48 weeks after discontinuation. The time to relapse was 33 ± 15 weeks. Elevation of HBV DNA and ALT levels over baseline were only observed in 12.5% of relapse patients. There were no significant differences in baseline characteristics (sex, HBV genotype, age or ALT levels) or time on consolidation therapy between patients with relapse or sustained response. NUC discontinuation in HBeAg-positive CHB patients is feasible after achieving HBeAg seroconversion at a minimum of 24 weeks. There is further benefit to prolonging the time on consolidation therapy to reduce relapse. More than 48 weeks of sustained response is a predictive marker for long-term sustained response.

Association between copy number variations of HLA-DQA1 and ankylosing spondylitis in the Chinese Han population

Ankylosing spondylitis (AS) is a chronic inflammatory disease with complex genetic traits. Multiple sequence variations have been associated with AS, but explained only a proportion of heritability. The studies herein aimed to explore potential associations between genomic copy number variation (CNV) and AS of Han Chinese. Five AS patients were examined with the high-density comparative genomic hybridization (CGH) microarrays in the first screen test for AS associated CNVs. A total of 533 AS patients and 792 unrelated controls were examined in confirmation studies with the AccuCopy assays. A significant association was observed between the CNV of the HLA-DQA1 and AS. Comparing with controls, AS patients showed an aberrant copy number (CN), and significantly increased number of patients had more than 2 copies of the HLA-DQA1. Therefore, CNV of the HLA-DQA1 may play an important role in susceptibility to AS in Han Chinese population.

A simply HPLC method for determination of cefpodoxime in Chinese volunteer and pharmacokinetic study

A sensitive HPLC method was developed for the determination of cefpodoxime in human plasma. After protein precipitation with acetonitrile, sample was injected into the HPLC system for analysis. The chromatographic separation was carried out on a Diamonsil C18 column with a mobile phase consisting of acetonitrile-water. The mobile phase composed of water (containing 20 mmol/L monoammonium phosphate) and acetonitrile (90: 10, v/v). The detection wavelength was set at 254 nm. The standard curve for cefpodoxime was linear over the concentration range of 0.05-8 μg/mL with a lower limit of quantification of 0.05 μg/mL. The intra- and inter-day RSD values were lower than 10%, and the RE values were within±5%. For the pharmacokinetic analysis of plasma, the mean (SD) values obtained for the formulation were: Cmax, 4.21 (0.62) µg/mL; Tmax, 2.47 (0.61) h; t1/2, 2.38 (0.46) h; AUC0-24 h, 21.13 (3.39) µg/mL/h; and AUC0-∞, 23.34 (3.87) µg/mL/h; MRT, 2.21 (0.41) h, respectively.

Measurement of the azimuthal anisotropy of neutral pions in Pb-Pb collisions at sqrt[s](NN)] = 2.76 TeV

First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of sqrt[s(NN)] = 2.76 TeV are presented. The amplitudes of the second Fourier component (v(2)) of the π(0) azimuthal distributions are extracted using an event-plane technique. The values of v(2) are studied as a function of the neutral pion transverse momentum (p(T)) for different classes of collision centrality in the kinematic range 1.6<p(T) <8.0 GeV/c, within the pseudorapidity interval |η|<0.8. The CMS measurements of v(2) (p(T)) are similar to previously reported π(0) azimuthal anisotropy results from sqrt[s(NN)] = 200 GeV Au-Au collisions at RHIC, despite a factor of ∼ 14 increase in the center-of-mass energy. In the momentum range 2.5<p(T)<5.0 GeV/c, the neutral pion anisotropies are found to be smaller than those observed by CMS for inclusive charged particles.

CD44v6 expression in human skin keratinocytes as a possible mechanism for carcinogenesis associated with chronic arsenic exposure

Inorganic arsenic is a well-known human skin carcinogen. Chronic arsenic exposure results in various types of human skin lesions, including squamous cell carcinoma (SCC). To investigate whether mutant stem cells participate in arsenic-associated carcinogenesis, we repeatedly exposed the human spontaneously immortalized skin keratinocytes (HaCaT) cell line to an environmentally relevant level of arsenic (0.05 ppm) in vitrofor 18 weeks. Following sodium arsenite administration, cell cycle, colony-forming efficiency (CFE), cell tumorigenicity, and expression of CD44v6, NF-κB and p53, were analyzed at different time points (0, 5, 10, 15, 20, 25 and 30 passages). We found that a chronic exposure of HaCaT cells to a low level of arsenic induced a cancer stem-like phenotype. Furthermore, arsenictreated HaCaT cells also became tumorigenic in nude mice, their growth cycle was predominantly in G2/M and S phases. Relative to nontreated cells, they exhibited a higher growth rate and a significant increase in CFE. Western blot analysis found that arsenic was capable of increasing cell proliferation and sprouting of cancer stem-like phenotype. Additionally, immunohistochemical analysis demonstrated that CD44v6 expression was upregulated in HaCaT cells exposed to a low level of arsenic during early stages of induction. The expression of CD44v6 in arsenic-treated cells was positively correlated with their cloning efficiency in soft agar (r=0.949, P=0.01). Likewise, the expressions of activating transcription factor NF-κB and p53 genes in the arsenic-treated HaCaT cells were significantly higher than that in non-treated cells. Higher expressions of CD44v6, NF-κB and p53 were also observed in tumor tissues isolated from Balb/c nude mice. The present results suggest that CD44v6 may be a biomarker of arsenicinduced neoplastic transformation in human skin cells, and that arsenic promotes malignant transformation in human skin lesions through a NF-κB signaling pathway-stimulated expression of CD44v6.