A ratiometric fluorescent sensing of proanthocyanidins by MnO2 nanosheets simultaneously tuning the photoluminescence of Au/AgNCs and thiamine.

By simultaneously regulating the photoluminescence of alloy Au/Ag nanoclusters (NCs) and thiamine (VB1) through MnO2 nanosheets (MnO2 NS), a novel ratiometric fluorescent probe (RF-probe) was established for sensitively and selectively monitoring proanthocyanidins (PAs). The introduction of Ag (I) ions could enhance significantly the quantum yields (QYs, 11.1%) of AuNCs based on the synthetic method of UVI (UV irradiation) combined with MWH (microwave heating). MnO2 NS could quench the fluorescence (FL) of Au/AgNCs mainly coming from Förster resonance energy transfer (FRET), while it could act as a nanozyme catalyst for directly catalyzing the oxidation of VB1 to produce highly fluorescent oxVB1. In the presence of PAs, MnO2 was reduced to Mn2+, which caused that its quenching capacity and oxidase-like activity were vanished, thus the FL of oxVB1 and Au/AgNCs was reduced and recovered. The concentration of PAs could be monitored by the RF-probe with a linear range of 0.27-22.4 µmol L-1 and corresponding limit of detection (LOD) and limit of quantification (LOQ) were calculated to be 75.9 and 250.5 nmol L-1. Furthermore, the RF-probe was successfully used for the determination of PAs in mineral water, PAs additive and PAs capsule with satisfactory results compared to the standard HPLC method.

The Association Between Obstructive Sleep Apnea and Nonarteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis.

PURPOSE: Nonarteritic anterior ischemic optic neuropathy (NAION) is a multifactorial disease, and recently epidemiologic studies have investigated the association between obstructive sleep apnea (OSA) and NAION. A systematic review of the association of OSA and NAION has not been performed. Therefore, the current meta-analysis was performed to assess such potential association between OSA and risk of NAION. METHODS: A systematic search of PubMed and EMBASE databases was performed for published studies evaluating the association between OSA and NAION. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for categorical risk estimates. Sensitivity analyses and subgroup analyses were also performed to assess the robustness of pooled outcomes. RESULTS: A total of four prospective cohort studies and one case-control study met our inclusion criteria. The pooled OR of developing NAION in the subjects with OSA was 6.18 (95% CI, 2.00-19.11) versus non-OSA controls. Sensitivity analyses showed that no matter one study excluded, the pooled OR did not change significantly, which indicated that the evidence was robust. In subgroup analyses, a significant association was seen in studies matched systemic risk factors (OR, 5.00; 95% CI, 2.22-11.25), but not in those non-matched. The magnitude and direction of effects were also affected by methodological variability, including study design, and diagnosis of OSA. CONCLUSIONS: The findings from this meta-analysis supported the robust evidence that OSA was a strong independent risk factor of NAION. Relative to non-OSA controls, the subjects with OSA were found to have a more than sixfold risk of NAION. In future, more well-designed studies are needed to confirm these findings.

The mechanism of lipid raft mediating chemoresistance of cervical cancer.

OBJECTIVE: To investigate the mechanism of lipid raft mediating chemotherapy resistance in cervical cancer. METHODS: This experiment was carried out in the Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China from June 2010 to February 2011. Hela cells were divided into 6 groups: control group (Ctrl), cisplatin group (Cis), lipid raft interference agent group (MCD), NADPH oxidase inhibitor group (Apo), lipid raft interference agent combined with cisplatin group (MCD+Cis), and NADPH oxidase inhibitor combined with cisplatin group (Apo+Cis). After the cervical cancer cells were treated with a correspondent agent for 24 hours, the number of surviving cells were measured utilizing cell counting kits-8 (CCK-8), and the hypoxia inducible factor-1alpha (HIF-1alpha) levels were detected by Western blotting. Reactive oxygen species (ROS) levels were measured indirectly by detection of dichlorodihydrofluorescein fluorescence activity. RESULTS: The cell growth of MCD slowed down (survival cells was 62% compared with the Ctrl group), with the Apo group showing a similar effect (65% in the control group), and 49% for the Cis group, MCD+Cis was 21%, and Apo+Cis was 23%. While the level of HIF-1alpha protein and ROS of the MCD group, Apo group, Cis group, MCD+Cis group and Apo+Cis group were decreased significantly compared to the control group. The level of HIF-1alpha of MCD group decreased by 69.9%, Apo group by 60.2%, Cis group was 55.5%, MCD+Cis group by 21.1% and Apo+Cis group by 25.4%, while the level of ROS also decreased in the MCD group by 38.6%, Apo group by 35.3%, Cis group by 24%, MCD+Cis group by 12.3% and Apo+Cis group by 12.8%. CONCLUSION: Lipid raft may up-regulate ROS level and HIF-1alpha expression through activating NADPH oxidase, and thus promote chemotherapy resistance in cervical cancer.

Interaction between water-soluble rhodium complex RhCl(CO)(TPPTS)2 and surfactants probed by spectroscopic methods.

The interactions of rhodium complex RhCl(CO)(TPPTS)(2) [TPPTS=P(m-C(6)H(4)SO(3)Na)(3)] with cationic, nonionic, and anionic surfactants have been investigated by UV-vis, fluorescence and (1)H NMR measurements. The presence of four different species of RhCl(CO)(TPPTS)(2) in cationic cetyltrimethylammonium (CTAB) solution has been demonstrated: free rhodium complex, rhodium complex bound to CTAB monomer, rhodium complex bound to CTAB premicelles, rhodium complex bound to CTAB micelles. The spectroscopy data show that RhCl(CO)(TPPTS)(2) can adsorb on the interface of cationic CTAB micelles by strong electrostatic attraction, weakly bind to the nonionic polyoxyethylene (20) sorbitan monolaurate (Tween 20) micelles by hydrophobic interaction, and does not interact with anion sodium dodecyl sulfate (SDS) micelles due to the strong electrostatic repulsion.

[Antimotion sickness effects of ginsenosides combined with dexamethasone in rats].

OBJECTIVE: To investigate the antimotion sickness effects of ginsenosides combined with dexamethasone in rats. METHODS: Fifty SD rats were randomly divided into 5 groups: normal saline, scopolamine-treated, ginsenosides-treated, dexamethasone-treated and ginsenosides plus dexamethasone-treated groups. There were 10 rats in each group. The rats in each group were fed with corresponding ingredients respectively, and then the rats were exposed to abnormal acceleration for one hour. The motion sickness index, the level of kaolin consumption and the course and time of spontaneous activity were observed. RESULTS: The motion sickness index and the level of kaolin consumption of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group were significantly lower than those in normal saline group. And the course and time of spontaneous activity of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group were significantly higher than those in normal saline group. The level of body weight increment of acceleration-exposed rats in ginsenosides plus dexamethasone-treated group was significantly higher than that in dexamethasone-treated group. CONCLUSION: Ginsenosides combined with dexamethasone can significantly increase tolerance to acceleration of rats, and the drug combination can decrease side effects of methylprednisolone, such as body weight loss.