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In order to solve the problem of heavy metal-organic compound soil pollution, in this paper, we developed a highly efficient electro kinetic-laccase combined remediation (EKLCR) system. The results showed that the EKLCR system had an obvious migration effect on heavy metals (copper and cadmium) and good migration-degradation effect on phenanthrene. The migration rates of copper and cadmium were 48.3% and 40.3%, respectively. Especially, with the presence of laccase, the removal rate of phenanthrene on Cu2+-contaminated soil was higher than that of Cd2+-contaminated soil due to the significant effect of heavy metals on the enzymatic activity of laccase. The average migration-degradation rate of phenanthrene by EKLCR system was 45.4%. Finally, gas chromatography-mass spectrometry (GC/MS) was used to analyze the degradation intermediates of phenanthrene in the soil, which included 9,10-Phenanthrenequinone, phthalic acid, and 2,2-Biphenyldicarboxylic Acid. In addition, we give the possible degradation pathways of phenanthrene, 2,2-Biphenyldicarboxylic Acid is further degraded to produce phthalic acid. The products of the phthalic acid metabolic pathway are protocatechuic acid, pyruvic acid or succinic acid, the final products of these organic acids are carbon dioxide and water.

Chronic obstructive pulmonary disease (COPD) is a common airway disease, and epithelial mesenchymal transition (EMT) is participated in the pathogenesis of COPD. However, the role of CD147 in COPD remains largely unknown. In order to clarify the role of CD147 in EMT induced by cigarette smoke, we established animal and cell model of EMT by mean of cigarette smoke exposure and detected the expressions of CD147 and EMT markers

In this paper, laccase was immobilized with the adsorption-crosslinking method in which biochar was used as the carrier and glutaraldehyde was used as the crosslinking agent. Firstly, the optimal immobilization conditions and optimal operating conditions were investigated, and then the stability of both free laccase and immobilized laccase was compared. Finally, the 2,4-dichlorophenol contaminated soil was remedied with both free laccase and immobilized laccase, and the improvement on the remediation of the contaminated soil by immobilized laccase was analysed through the ecological evaluation. The results showed that in the optimal immobilization condition, the biochar with a particle size of 30 mesh should be selected, and glutaraldehyde with a volume fraction of 4% and 20 mL of laccase solution should be added to complete the 6-hour adsorption operation and 4-hour crosslinking operation. The stability of immobilized laccase was better than that of free laccase, and the thermal deactivation kinetic equation for the free laccase was ln

Compositional data are known as a sort of complex multidimensional data with the feature that reflect the relative information rather than absolute information. There are a variety of models for regression analysis with compositional variables. Similar to the traditional regression analysis, the heteroskedasticity still exists in these models. However, the existing heteroskedastic regression analysis methods cannot apply in these models with compositional error term. In this paper, we mainly study the heteroskedastic linear regression model with compositional response and covariates. The parameter estimator is obtained through weighted least squares method. For the hypothesis test of parameter, the test statistic is based on the original least squares estimator and corresponding heteroskedasticity-consistent covariance matrix estimator. When the proposed method is applied to both simulation and real example, we use the original least squares method as a comparison during the whole process. The results implicate the model's practicality and effectiveness in regression analysis with heteroskedasticity.

The logratio methodology is not applicable when rounded zeros occur in compositional data. There are many methods to deal with rounded zeros. However, some methods are not suitable for analyzing data sets with high dimensionality. Recently, related methods have been developed, but they cannot balance the calculation time and accuracy. For further improvement, we propose a method based on regression imputation with Q-mode clustering. This method forms the groups of parts and builds partial least squares regression with these groups using centered logratio coordinates. We also prove that using centered logratio coordinates or isometric logratio coordinates in the response of partial least squares regression have the equivalent results for the replacement of rounded zeros. Simulation study and real example are conducted to analyze the performance of the proposed method. The results show that the proposed method can reduce the calculation time in higher dimensions and improve the quality of results.

Yuling Luo, Zhongbing Liu, Xiaoqin Zhang, Juan Huang, Xin Yu, Jinwei Li, Dan Xiong, Xiaoduan Sun, Zhirong Zhong Department of Pharmaceutical Sciences, School of Pharmacy, Southwest Medical University, Luzhou, Sichuan,People’s Republic of ChinaAbstract: The aim of the present study was to develop a novel dosage form of multivesicular liposomes for oleanolic acid (OA) to overcome its poor solubility, prolong therapeutic drug levels in the blood, and enhance the antitumor effect on hepatocellular carcinoma. OA-encapsulated multivesicular liposomes (OA-MVLs) were prepared by a double-emulsion method, and the formulation was optimized by the central composite design. The morphology, particle size, and drug-loading efficiency of OA-MVLs were investigated. Furthermore, OA-MVLs were also characterized both in vitro and in vivo. The results showed that OA-MVLs were spherical particles with an average particle size of 11.57µm and an encapsulation efficiency of 82.3%±0.61%. OA-MVLs exhibited a sustained-release pattern in vitro, which was fitted to Ritger–Peppas equation. OA-MVLs inhibited the growth of human HepG2 cells which was confirmed by the MTT assay and fluorescence microscopy detection. The in vivo release of OA from OA-MVLs exhibited a sustained manner, indicating a longer circulation time compared to OA solution. The in vivo toxicity study indicated that medium-dose OA-MVLs exerted no toxic effect on the hosts. Importantly, OA-MVLs suppressed the growth of murine H22 hepatoma and prolonged the survival of tumor-bearing mice. In conclusion, the poorly soluble OA could be encapsulated into MVLs to form a novel controlled-release drug delivery system. The present study may hold promise for OA-MVLs as a new dosage form for sustained-release drug delivery in cancer therapy.Keywords: oleanolic acid, multivesicular liposomes, murine hepatocellular carcinoma, controlled release, cancer therapy

To solve the heteroscedastic problem in linear regression, many different heteroskedasticity-consistent covariance matrix estimators have been proposed, including HC0 estimator and its variants, su...

Ubiquitin adducts surrounding DNA double-strand breaks (DSBs) have emerged as molecular platforms important for the assembly of DNA damage mediator and repair proteins. Central to these chromatin modifications lies the E2 UBC13, which has been implicated in a bipartite role in priming and amplifying lys63-linked ubiquitin chains on histone molecules through coupling with the E3 RNF8 and RNF168. However, unlike the RNF8-UBC13 holoenyzme, exactly how RNF168 work in concert with UBC13 remains obscure. To provide a structural perspective for the RNF168-UBC13 complex, we solved the crystal structure of the RNF168 RING domain. Interestingly, while the RNF168 RING adopts a typical RING finger fold with two zinc ions coordinated by several conserved cystine and histine residues arranged in a C3HC4 “cross-brace” manner, structural superimposition of RNF168 RING with other UBC13-binding E3 ubiquitin ligases revealed substantial differences at its corresponding UBC13-binding interface. Consistently, and in stark contrast to that between RNF8 and UBC13, RNF168 did not stably associate with UBC13 in vitro or in vivo. Moreover, domain-swapping experiments indicated that the RNF8 and RNF168 RING domains are not functionally interchangeable. We propose that RNF8 and RNF168 operate in different modes with their cognate E2 UBC13 at DSBs.

The present study describes a novel approach treating freshly cleared cells when simulating incompressible flows using the immersed boundary method. The method calculates material derivative in Lagrangian coordinate system to approximate the solution at the freshly cleared cells. In this study, we use a simple test case to compare our proposed method with the commonly used one-dimensional interpolation method in the Eulerian coordinate system.