Degradation of Sodium Acetate by Catalytic Ozonation Coupled with a Mn-Functionalized Fly Ash: Reaction Parameters and Mechanism.

Supported ozone catalysts usually take alumina, activated carbon, mesoporous molecular sieve, graphene, etc. as the carrier for loading metal oxide via the impregnation method, sol-gel method and precipitation method. In this work, a Mn-modified fly ash catalyst was synthesized to reduce the consumption and high unit price of traditional catalyst carriers like alumina. As a solid waste discharged from coal-fired power plants fueled by coal, fly ash also has porous spherical fine particles with constant surface area and activity, abd is expected to be applied as the main component in the synthesis of ozone catalyst. After the pretreatment process and modification with MnOx, the obtained Mn-modified fly ash exhibited stronger specific surface area and porosity combined with considerable ozone catalytic performance. We used sodium acetate as the contaminant probe, which is difficult to directly decompose with ozone as the end product of ozone oxidation, to evaluate the performance of this Mn-modified fly. It was found that ozone molecules can be transformed to generate ·OH, ·O2- and 1O2 for the further oxidation of sodium acetate. The oxygen vacancy produced via Mn modification plays a crucial role in the adsorption and excitation of ozone. This work demonstrates that fly ash, as an industrial waste, can be synthesized as a potential industrial catalyst with stable physical and chemical properties, a simple preparation method and low costs.

Pharmacophore identification, docking and "in silico" screening for novel CDK1 inhibitors.

Pharmacophore models of cyclin-dependent kinase-1 (CDK1) inhibitors were established by using the Catalyst/HypoGen. The best pharmacophore model, Hypo1, consists of one hydrogen bond acceptor (HBA), one hydrogen bond donor (HBD), one hydrophobic (HY) and one ring aromatic (RA) feature. The validation results of Hypo1 through cost analysis, test set prediction, Fisher's cross method and receiver operating characteristic (ROC) study indicated that the Hypo1 was statistically valuable and reliable in identifying structural diverse CDK1 inhibitors. It is further supported by the consistent results from molecular docking studies. Finally, the Hypo1 was used to "in silico" screen the NCI and MayBridge database. The preferable hits obtained were further docked into ATP binding site of CDK1, and nine promising compounds were retrieved as novel potential CDK1 inhibitors for further studies.

QSAR models for isoindolinone-based p53-MDM2 interaction inhibitors using linear and non-linear statistical methods.

The design and optimization of p53-MDM2 interaction inhibitors has attracted a great deal of interest in the development of new anticancer agents. Systematical 2D-QSAR studies on 98 isoindolinone-based p53-MDM2 interaction inhibitors were carried out using linear and the non-linear mathematical methods. At first, a forward stepwise-multiple linear regression model (FS-MLR) was proposed with reasonable statistical parameters (R(2)(train) =0.881, Q(2)(loo) =0.847, R(2)(test) =0.854). Then, enhanced replacement method-multiple linear regression (ERM-MLR) and support vector machine regression (SVMR) were applied to set up more accurate models (ERM-MLR: R(2)(train) =0.914, Q(2)(loo) =0.894 and R(2)(test) =0.903; SVMR: R(2)(train) =0.924, Q(2)(loo) =0.920 and R(test) (2) of 0.874). Furthermore, the reliability and application value of the ERM and SVMR model was also validated in virtual screening through receiver operating characteristic studies.

Toxicological characteristics of nanoparticulate anatase titanium dioxide in mice.

In an effort to examine liver injury, immune response, and other physiological effects in mice caused by intragastric administration of nanoparticulate anatase titanium dioxide (5nm), we assessed T lymphocytes, B lymphocyte and NK lymphocyte counts, hematological indices, biochemical parameters of liver functions, and histopathological changes in nanoparticulate titanium dioxide -treated mice. Indeed, mice treated with higher dose nanoparticulate titanium dioxide displayed a reduction in body weight, an increase in coefficients of the liver and histopathological changes in the liver. Specifically, in these nanoparticulate titanium dioxide -treated mice, interleukin-2 activity, white blood cells, red blood cells, haemoglobin, mean corpuscular haemoglobin concentration, thrombocytes, reticulocytes, T lymphocytes (CD3(+), CD4(+), CD8(+)), NK lymphocytes, B lymphocytes, and the ratio of CD4 to CD8 of mice were decreased, whereas NO level, mean corpuscular volume, mean corpuscular haemoglobin, red (cell) distribution width, platelets, hematocrit, mean platelet volume of mice were increased. Furthermore, liver functions were also disrupted, as evidenced by the enhanced activities of alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase and cholinesterase, an increase of the total protein, and the reduction of ratio of albumin to globulin, the total bilirubin, triglycerides, and the total cholesterol levels. These results suggested that the liver function damage observed in mice treated with higher dose nanoparticulate titanium dioxide is likely associated with the damage of haemostasis blood system and immune response. However, low dose nanoparticulate anatase TiO(2) has little influences on haemostasis blood system and immune response in mice.

QSAR study of Akt/protein kinase B (PKB) inhibitors using support vector machine.

A three-class support vector classification (SVC) model with high prediction accuracy for the training, test and overall data sets (95.2%, 88.6% and 93.1%, respectively) was developed based on the molecular descriptors of 148 Akt/protein kinase B (PKB) inhibitors. Then, support vector regression (SVR) method was applied to set up a more accurate model with good correlation coefficient (r(2)) for the training, test and overall data sets (0.882, 0.762 and 0.840, respectively). Enrichment factors (EF) and receiver operating curves (ROC) studies of database screening were also performed either using the SVR model alone or assisted with the SVC model, the results of which demonstrated that the established models could be useful and reliable tools in identifying structurally diverse compounds with Akt inhibitory activity.

Biochemical toxicity of nano-anatase TiO2 particles in mice.

Previous research on the biological and toxic effects of nano-TiO(2) particles on animals only limit to a single dose. However, the toxicity caused by single dose nano-TiO(2) does not truly represent ecological and health effects of nano-TiO(2) retained in the environment. In order to further evaluate the toxicity of nano-TiO(2) particles, nano-anatase TiO(2) (5 nm) was injected into the abdominal cavity of ICR mice everyday for 14 days and the coefficients of organs and serum biochemical parameters were investigated. The results showed that, with increasing doses of nano-anatase TiO(2), the coefficients of liver, kidney, and spleen increased gradually, while the coefficients of lung and brain decreased gradually, and the coefficient of heart had little change. The order of the titanium accumulation in the organs was liver > kidneys > spleen > lung > brain > heart. The serum biochemical parameters with lower dose of nano-anatase TiO(2) showed little difference compared with the control mice, while with higher dose of nano-anatase TiO(2), the indicators of liver function, such as alkaline phosphatase, alanine aminotransferase, leucine acid peptide, pseudocholinesterase, total protein, and albumin level, were enhanced significantly; the indicators of kidney function, such as uric acid and blood urea nitrogen, were decreased; the activities of aspartate aminotransferase, creatine kinase, lactate dehydrogenase, and alpha-hydroxybutyrate dehydrogenase, indicator of the myocardium function, were increased. The contents of triglycerides, glucose, and high-density lipoprotein cholesterol were significantly elevated. Taken together, nano-anatase TiO(2) in higher dose caused serious damage to the liver, kidney, and myocardium of mice and disturbed the balance of blood sugar and lipid in mice. The accumulation of titanium in the organs might be closely related to the coefficients of organs and the inflammatory responses of mice.

Synthesis, biological evaluation and quantitative structure-activities relationship of flavonoids as vasorelaxant agents.

A series of flavonoid derivatives were designed, synthesized. Their vasorelaxant activities were evaluated experimentally against rat aorta rings pretreated with phenylephrine (PE). Among them, 6-hydroxy-8-allyl-4'-chloro-flavanone 8q exhibited the highest vasodilatory activity (EC(50)=4.6 microM, E(max)=95.1%). The 3D-QSAR analysis was carried out by comparative molecular field analysis (CoMFA) method, and a statistically reliable model with good predictive power (r(2)=0.872 and q(cv)(2)=0.496) was established. The contour plots of CoMFA model provide a good insight into the structure-activity relationships of these compounds and may be used to design more potent flavonoids derivatives as vasorelaxant agents.

The Acute Liver Injury in Mice Caused by Nano-Anatase TiO2.

Although it is known that nano-TiO2or other nanoparticles can induce liver toxicities, the mechanisms and the molecular pathogenesis are still unclear. In this study, nano-anatase TiO2(5 nm) was injected into the abdominal cavity of ICR mice for consecutive 14 days, and the inflammatory responses of liver of mice was investigated. The results showed the obvious titanium accumulation in liver DNA, histopathological changes and hepatocytes apoptosis of mice liver, and the liver function damaged by higher doses nano-anatase TiO2. The real-time quantitative RT-PCR and ELISA analyses showed that nano-anatase TiO2can significantly alter the mRNA and protein expressions of several inflammatory cytokines, including nucleic factor-κB, macrophage migration inhibitory factor, tumor necrosis factor-α, interleukin-6, interleukin-1ß, cross-reaction protein, interleukin-4, and interleukin-10. Our results also implied that the inflammatory responses and liver injury may be involved in nano-anatase TiO2-induced liver toxicity.

Identification of SVM-based classification model, synthesis and evaluation of prenylated flavonoids as vasorelaxant agents.

Support vector machine (SVM) was applied to predict vasorelaxation effect of different structural molecules. A good classification model had been established, and the accuracy in prediction for the training, test, and overall datasets was 93.0%, 82.6%, and 89.5%, respectively. Furthermore, the model was used to predict the activity of a series of prenylated flavonoids. According to the estimated result, eleven molecules 1-11 were selected and synthesized. Their vasodilatory activities were determined experimentally in rat aorta rings that were pretreated with phenylephrine (PE). Structure-activity relationship (SAR) analysis revealed that flavanone derivatives showed the most potent activities, while flavone and chalcone derivatives exhibited medium activities.