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Polycyclic aromatic hydrocarbons (PAHs) are widespread and persistent organic pollutants with high carcinogenic effect and toxicity; their behavior and fate in the soil–plant system have been widely investigated. In the present paper, meta-analysis was used to explore the interaction between plant growth and dissipation of PAHs in soil based on the large body of published literature. Plants have a promoting effect on PAH dissipation in soils. There was no difference in PAH dissipation between soils contaminated with single and mixed PAHs. However, plants had a more obvious effect on PAH dissipation in freshly-spiked soils than in long-term field-polluted soils. Additionally, a positive effect of the number of microbial populations capable of degrading PAHs was observed in the rhizosphere compared with the bulk soil. Our meta-analysis established the importance of the rhizosphere effect on PAH dissipation in variety of the soil–plant systems. [Copyright &y& Elsevier]

Abstract: Regioselective Michael addition of purine derivatives to α,β-unsaturated carbonyl compounds could be catalyzed by d-aminoacylase amano (DA) in DMSO. The influence of reaction conditions on the Michael addition, including solvent, temperature, and enzyme concentration was systematically investigated. Then we extended this methodology to six structurally diverse purine derivatives and a variety of α,β-unsaturated carbonyl compounds. 21 Michael adducts were selectively synthesized in moderate to high yields. It is the first report on enzyme-catalyzed Michael addition for the preparation of purine derivatives. [Copyright &y& Elsevier]

Abstract: A simple and efficient protocol for the anti-Markovnikov addition of thiols to vinyl ethers under solvent- and catalyst-free conditions has been established. A series of thiol ethers containing oxygen atom were obtained with good to excellent yields. [Copyright &y& Elsevier]

Abstract: A facile and efficient strategy to prepare drug derivatives with saccharides was developed, and 12 drug–saccharide conjugates were obtained by selective enzymatic synthesis methods. When the transesterification of chlorphenesin vinyl esters with glucose was chosen as a model reaction, the influence of reaction conditions was optimized. Then, we successfully prepared a series of chlorphenesin–saccharide derivatives of three monosaccharides (glucose, mannose and galactose) and three disaccharides (maltose, lactose and sucrose). In order to study the relationship between the solubility of drug–saccharide conjugates and the structure of parent drugs, five hydrophobic drugs (chlorphenesin, mephenesin, guaifenesin, propranolol and clorprenaline) were chosen as substrates to synthesize drug–saccharide conjugates. The results indicated that the aqueous solublity of drug–saccharide derivatives was greatly improved, which was changed by different saccharides and the structure of parent drugs. [Copyright &y& Elsevier]

Abstract: A series of 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-[(4-substitutedphenyl)-piperazin-1-yl]-propan-2-ols have been designed and synthesized on the basis of the structure–activity relationships and antimycotic mechanism of azole antifungal agents. Their structures were confirmed by elemental analysis, IR, MS and 1H NMR. Results of preliminary antifungal tests against eight human pathogenic fungi (Candida albicans, Candida parapsilosis, Candida tropicalis, Cryptococcus neoformans, Aspergillus fumigatus, Trichophyton rubrum, Fonsecaea compacta, and Microsporum gypseum) in vitro showed that all title compounds exhibited activity against fungi tested to some extent. Among the compounds tested, all compounds showed higher activity against C. albicans than fluconazole in vitro. Compounds 3, 6–8, 28, 29, and 32 exhibited the same activities against C. albicans as voriconazole (with the MIC value of 0.0152μg/mL). Compounds 3, 6, and 7 showed higher activity against C. parapsilosis than all five positive controls. [Copyright &y& Elsevier]

Abstract: A novel and efficient enzymatic promiscuous protocol for aza-Michael addition of aromatic N-heterocycles to α,β-unsaturated compounds has been described. The reactions were catalyzed by promiscuous zinc-active-site acylase in organic solvent at 50°C. The strategy works with a broad range of N-heterocycles to afford the corresponding Michael adduct with good yields in several hours (0.5–6h). This catalytic promiscuity is the first example of metal-active-site enzyme-catalyzed aza-Michael addition for aromatic N-heterocycles. [Copyright &y& Elsevier]

Abstract: A fast and green protocol for the Michael addition of N-heterocycles to α,β-unsaturated compounds at room temperature was developed using a basic ionic liquid, 1-methyl-3-butylimidazolium hydroxide, [bmIm]OH, as a catalyst and a reaction medium. The reactions were performed at room temperature with good yields in short reaction times (0.5–3h). This strategy is quite general and it works with a broad range of N-heterocycles, including five-membered N-heterocycles, pyrimidines and purines. The recovered ionic liquid could be reused for several cycles with consistent activity. [Copyright &y& Elsevier]

Abstract: A novel and highly efficient protocol for Markovnikov’s addition using ionic liquid as a catalytic green solvent is described. The strategy is especially useful in the synthesis of N-heterocycle derivatives with biological activity. This reaction widens largely the applicability of ionic liquid in organic synthesis. [Copyright &y& Elsevier]

Abstract: A cDNA fragment coding for domains I and II of mouse macrophage metalloelastase (MME) was transfected into murine CT-26 colon cancer cells that are MME deficient. An orthotopic implantation model was established by using MME-transfected cells. In MME-transfected primary tumors, it demonstrated that tumor growth and microvessel formation were significantly inhibited compared with the controls. The expression of vascular endothelial growth factor (VEGF) mRNA and protein was significantly lower in MME-transfected group compared with those in the controls. Our data show that both MME and VEGF gene expression is highly associated with the vascularity of tumors, which may depend on a balance between MME and VEGF expression. [Copyright &y& Elsevier]

Abstract: A pot experiment was conducted to appraise the hazards of bound residues of metsulfuron-methyl in soil at six levels (0, 0.050, 0.089, 0.158, 0.281, and 0.500mgkg−1) to the growth of four rice varieties (Xiushui 63, Eryou 810, Liangyoupeijiu, and Zhenong 952). The morphological characteristics of rice roots like root number, total length, surface area of rice roots, and rice biomass were determined. The results showed that the bound residues of metsulfuron-methyl in soil impacted the growth of rice. Root number, total length of roots, surface area of roots, and biomass were restrained by bound residues of metsulfuron-methyl in soil. The inhibition rate of root growth increased from 69.46–81.32% to 85.18–95.97% with the increasing of levels of bound residues of metsulfuron-methyl from 0.05mgkg−1 to 0.50mgkg−1. The number of rice roots could be taken as a sensitive index to screen the rice varieties endurable to bound residues of metsulfuron-methyl in soil and to predict the potential hazards of bound residues of metsulfuron-methyl in soil to rice. The level of bound residues of metsulfuron-methyl in soil causing the root numbers decreased by 50% (IC50) followed the order of Xiushui 63

The combination of the topoisomerase I (Topo I) inhibitor CPT-11 with the anti-epidermal growth factor receptor (EGFR) agent Gefitinib (Iressa™, ZD1839) represents a promising medical approach for colorectal cancer patients. In this report, we provide pre-clinical evidences for their optimal combination schedule in HT-29 and LoVo human colon cancer cell lines. We analyzed the different effects that three different combination schedules of SN-38 (the active CPT-11 metabolite) and Gefitinib (Gefitinib before; Gefitinib simultaneously; Gefitinib after SN-38) have on cell growth, cell cycle, apoptosis, and expression/phosphorylation of EGFR, Topo I and some steps of the signal transduction pathway. We first determined the IC50 of each drug choosing the 5 days exposure for Gefitinib (0.6 and 3.8 μM for LoVo and HT-29 cells, respectively) and 1 day exposure for SN-38 (0.31 and 0.5 μM for LoVo and HT-29 cells, respectively). The different drug combination schedules were tested in various concentrations by using equiactive concentrations of the two drugs. The cytotoxicity of Gefitinib and SN-38 combination was schedule- and concentration-dependent but not cell line-specific. The most synergistic schedule was Gefitinib given after SN-38, with combination indexes (CI) of 0.007 and 0.454 in HT-29 and LoVo, respectively. Analysis of bio-molecular targets showed that Gefitinib was able to modulate SN-38 ability to inhibit Topo I, to accumulate cells in S-phase, and to induce apoptosis. Interestingly, SN-38 was able to activate EGFR and its signal transduction pathway. Confirming preliminary clinical experience of Gefitinib with other cytotoxic drugs, it seems that Gefitinib after SN-38 represents the best cytotoxic combination schedule but the biomolecular basis for this synergism remain to be completely elucidated. [Copyright &y& Elsevier]

ZD1839 (‘Iressa’), a selective epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), is currently undergoing preclinical and clinical evaluation in several solid tumors. The present study aimed to assess the effect of ZD1839 in combination with oxaliplatin in the colon cancer cell lines HT-29 and LoVo. For in vitro chemosensitivity testing, cells were treated with serial dilutions of each drug sequentially at a fixed ratio of doses that corresponded to 1/20, 1/10, 1/5, 1/2, 1, 1.5 and 2 times the individual ic50 values. Oxaliplatin followed by ZD1839 produced a synergistic effect. In contrast, oxaliplatin following ZD1839 exhibited an additive effect at best. Mass spectrometry examination revealed that ZD1839 modestly enhanced cellular oxaliplatin accumulation and platinum-DNA (Pt-DNA) adducts (P>0.05). In additional studies, high-performance liquid chromatography revealed that oxaliplatin had no effect on ZD1839 accumulation. In contrast, ZD1839 markedly inhibited removal of Pt-DNA adducts (P<0.05). With oxaliplatin treatment (1 day) followed by ZD1839 (1 day), then incubation with drug-free medium (1 day), 90% of Pt-DNA adducts remained. Apoptosis examination revealed that oxaliplatin-induced apoptosis was prolonged by sequential oxaliplatin followed by ZD1839 treatment compared with oxaliplatin alone. Further experiments revealed that ZD1839 decreased cellular γ-glutamyltransferase activity.Conclusions: The above observations provide a mechanistic explanation for the synergy of oxaliplatin followed by ZD1839, and suggest that this treatment combination warrants further preclinical and clinical investigation. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the impact of window settings on measurement of colon polyps with CT virtual colonoscopy with experiment. Twenty-four artificial polyps'' diameter were measured and scanned 10 times with identical scan parameters using a 64-multidetector computed tomographic scanner. The diameter of each polyp was measured using lung window and abdominal soft tissue window settings and compared with the actual diameter. The lung window setting offers accurate measurement of colon polyps. [Copyright &y& Elsevier]

Abstract: A series of 1-(1H-1,2,4-triazol-1-yl)-2-(2,4-difluorophenyl)-3-[(4-substitutedphenyl)-piperazin-1-yl]-propan-2-ols have been designed and synthesized on the basis of the structure–activity relationships and antimycotic mechanism of azole antifungal agents. Their structures were confirmed by elemental analysis, IR, MS, 1H NMR and 13C NMR. Results of preliminary antifungal tests against six human pathogenic fungi (Candida albicans, Candida parapsilosis, Cryptococcus neoformans, Candida tropicalis, inherently fluconazole-resistant Candida krusei, Candida glabrata) in vitro showed that all title compounds exhibited activity against fungi tested to some extent except against C. tropicalis. Compound 5b showed higher activity against C. albicans, C. parapsilosis and C. krusei than fluconazole, and its MIC values were determined to be 0.5μg/mL, 1μg/mL and 4μg/mL, respectively. Compound 5k showed higher activities against Torulopsis glabrata than fluconazole (with the MIC value of 2μg/mL). Compounds 5a, 5c, 5f, 5g, 5i exhibited higher activities against C. parapsilosis than fluconazole (with the MIC values of 2μg/mL, 2μg/mL, 2μg/mL, 1μg/mL and 2μg/mL, respectively). [Copyright &y& Elsevier]

Abstract: Fourteen low-molecular-weight organic acids (organic acids) and eight neutral monosaccharides (monosaccharides) were used to investigate the intrinsic link between ferrous iron [Fe(II)] accumulation and pentachlorophenol (PCP) degradation at the paddy soil–floodwater interface. Using logistic curve fitting, significant differences were observed between Fe(II) accumulation with organic acids and monosaccharides. These differences were attributed to large variations in the dissociation constants and the number of carbon atoms per molecule. A significant relationship was observed between the maximum capacity of Fe(II) accumulation and PCP degradation. Correlations were established between environmental variables including PCP, NaOAc-/HCl-extractable Fe(II), water soluble organic carbon (WSOC), anodic peak oxidation potential (Ep ) of Fe(II) species, oxidation–reduction potential (ORP), and pH. The increase in pH combined with WSOC consumption caused a decrease in Ep , which greatly enhanced the HCl-extractable Fe(II) accumulation and subsequently contributed to PCP degradation. [Copyright &y& Elsevier]

Abstract: Antitubercular drugs have been known to be potentially hepatotoxic and may lead to drug-induced liver injury. In this study, we aimed to investigate the protective effects of ursodeoxycholic acid (UDCA) on liver injury caused by co-administration with isoniazid and rifampicin, two famous antitubercular drugs. Liver injury was induced by co-treatment with isoniazid (75mg/kg) and rifampicin (150mg/kg) for one week. Mice were orally administered with UDCA (15, 50 and 150mg/kg) 30min before isoniazid and rifampicin. We show that serum alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were significantly increased in mice treated with isoniazid plus rifampicin. An obvious fatty accumulation, accompanied by mild necrosis and inflammation, was observed in liver of mice treated with rifampicin plus isoniazid. In addition, isoniazid plus rifampicin resulted in hepatic apoptosis, as determined by terminal dUTP nick-end labeling (TUNEL) staining and caspase-3 activation. Additional experiment showed that isoniazid plus rifampicin significantly increased the level of hepatic malondialdehyde (MDA) and caused glutathione (GSH) depletion and 3-nitrotyrosine (3-NT) residues in liver. UDCA pretreatment significantly attenuated isoniazid plus rifampicin induced oxidative stress in liver. Importantly, UDCA pretreatment significantly alleviated isoniazid plus rifampicin induced hepatic apoptosis. Moreover, UDCA-mediated anti-apoptotic effect seemed to be associated with its regulation of Bcl-2 and Bax gene expression in liver. These findings suggest that UDCA might protect against isoniazid and rifampicin induced liver injury through its anti-oxidative and anti-apoptotic effects. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the relative values of 2D plane view and 3D intracavity view of CT virtual colonoscopy in displaying colon excavated lesions. Cleaned porcine colon with ulcerative lesion was scanned with multidetector CT. The data were reconstructed and reviewed using 2D plane view and 3D volume-rendered images on a GE AW4.2 workstation. The 3D volume-rendered images showed superiority in displaying excavated lesions. [Copyright &y& Elsevier]

Abstract: Objective: To evaluate the clinical value of diffusion-weighted imaging (DWI) in combination with T2-weighted imaging (T2WI) for the detection of rectal cancer as compared with T2WI alone. Materials and methods: Forty-five patients with rectal cancer and 20 without rectal cancer underwent DWI with parallel imaging and T2WI on a 1.5T scanner. Images were independently reviewed by two readers blinded to the results to determine the detectability of rectal cancer. The detectability of T2W imaging without and with DW imaging was assessed by means of receiver operating characteristic analysis. The interobserver agreement between the two readers was calculated with kappa statistics. Results: The ROC analysis showed that each of two readers achieved more accurate results with T2W imaging combined with DW imaging than with T2W imaging alone significantly. The A z values for the two readers for each T2WI and T2WI combined with DWI were 0.918 versus 0.991 (p =0.0494), 0.934 versus 0.997 (p =0.0475), respectively. The values of kappa were 0.934 for T2WI and 0.948 for T2WI combined with DWI between the two readers. Conclusion: The addition of DW imaging to conventional T2W imaging provides better detection of rectal cancer. [Copyright &y& Elsevier]

Oncogene alterations have been clearly demonstrated to be related to the carcinogenesis and progression of oral squamous cell carcinoma (OSCC). However, the analysis of these alterations for screening and early diagnostic purposes generally requires invasive techniques for surgical removal of pathological epithelium. The aim of the present study was to assess the feasibility of fluorescence in situ hybridization (FISH) analysis of HER-2/neu amplification in oral mucosa brushings and to compare the HER-2/neu status with the history and smoking and drinking habits of healthy subjects. Cells obtained by centrifugation of oral brushings from 21 subjects (overall no. of cells: 5125) were suspended in physiological saline and fixed onto two slides for cytological evaluation and FISH analysis (dual-target, dual-color fluorescence assay) of the HER-2/neu gene and CEP17 centromere. A mean of 89.8% of the cells showed two HER-2/neu signals and a mean of 94% had two CEP17 signals at fluorescent microscopy. Finally, a mean of 96% of cells with HER-2/neu / CEP17 had a ratio equal to 1. No association between smoking and drinking habits, age and the HER-2/neu and CEP17 characteristics evaluated by FISH was found. [Copyright &y& Elsevier]

In the industrial multi-agent systems, the effect of the faults occurring on any subsystem may diffuse to the whole system through network topology and cause the control performance degradation. This paper aims to solve the issue of fault identification for uncertain multi-agent systems with sensor faults. Firstly, a randomized cooperative fault detection system composed by a group of decoupled filters is presented, where a joint fault detection performance assessment scheme is designed. On this basis, a novel topology reconstruction-based fault isolation strategy is proposed. Finally, two case studies on the multi-axis motion control system are conducted, and the results illustrate the effectiveness of the proposed framework. [ABSTRACT FROM AUTHOR]