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Abstract This study combined various non-invasive and micro-invasive analytical techniques to investigate the production process of coffin plank paintings excavated from a Northern Wei tomb in Zhijiabao Village, Datong City, Shanxi Province. Fiber-optic reflectance spectroscopy, portable Raman spectroscopy, and portable X-ray fluorescence spectroscopy were employed for in-situ non-invasive detection of coffin panel paintings. On that basis, micro-samples in smaller amounts than that of previous studies of the same type were collected and analyzed through optical microscopy, confocal micro-Raman spectroscopy, and scanning electron microscopy-energy dispersive spectroscopy. The results showed that the studied coffin plank decoration was painted after applying a layer of yellow primer to the plank surface. Specifically, cinnabar was used as the red material, pararealgar was used as the yellow color, an indigo and orpiment mixture was used as the green substance, the blue pigment was most likely an indigo and lead white mixture, gypsum was used the white material, and carbon black was used as the black pigment. Notably, the studied coffin plank was painted with a mixture of inorganic and organic materials to present the green and blue colors. This study provided not only a scientific basis for the conservation and restoration of this artifact but also new information for the research on Northern Wei art history.

Early allograft dysfunction (EAD) and early postoperative complications are two important clinical endpoints when evaluating clinical outcomes of liver transplantation (LT). We developed and validated two ICGR15-MELD models in 87 liver transplant recipients for predicting EAD and early postoperative complications after LT by incorporating the quantitative liver function tests (ICGR15) into the MELD score. Eighty seven consecutive patients who underwent LT were collected and divided into a training cohort (n = 61) and an internal validation cohort (n = 26). For predicting EAD after LT, the area under curve (AUC) for ICGR15-MELD score was 0.876, with a sensitivity of 92.0% and a specificity of 75.0%, which is better than MELD score or ICGR15 alone. The recipients with a ICGR15-MELD score ≥0.243 have a higher incidence of EAD than those with a ICGR15-MELD score <0.243 (P <0.001). For predicting early postoperative complications, the AUC of ICGR15-MELD score was 0.832, with a sensitivity of 90.9% and a specificity of 71.0%. Those recipients with an ICGR15-MELD score ≥0.098 have a higher incidence of early postoperative complications than those with an ICGR15-MELD score <0.098 (P < 0.001). Finally, application of the two ICGR15-MELD models in the validation cohort still gave good accuracy (AUC, 0.835 and 0.826, respectively) in predicting EAD and early postoperative complications after LT. The combination of quantitative liver function tests (ICGR15) and the preoperative MELD score is a reliable and effective predictor of EAD and early postoperative complications after LT, which is better than MELD score or ICGR15 alone. [ABSTRACT FROM AUTHOR]

An experimental method of measuring acoustic surface radiation resistance is developed. The principle of the method is based on obtaining source velocity and field pressure generated by the source. To measure surface radiation resistance, measuring probe was developed and measuring system was set up. Then, major factors that affect measurement accuracy is discussed and great improvements are got. After that, experiments of measuring baffled circular piston were conducted to analyze its applicable frequency range. To verify actual application effect, experiments of measuring the tube and cylinder heads of a diesel engine were performed. The results show that this measuring system can obtain resistance values in the frequency range from 460 to 1900 Hz with high precision. The measuring sys-tem has features of simple operation, convenient use, and high accuracy. Therefore, it can be used to determine surface resistance matrix of various structures. [ABSTRACT FROM AUTHOR]

The sorption by solid materials is one of the most important processes that affect the fate of hydrophobic organic pollutants in aquatic systems. Current studies focus on the sorption of hydrophobic pollutants by single natural solid material, whereas few studies compared the sorption behaviors of different solids. Furthermore, natural aquatic environment is a complex system where hydrophobic pollutants coexist with many other pollutants, but only limited studies reported the effects of coexisting components on the sorption. Here we studied the sorption of dichlorodiphenyltrichloroethanes (DDTs) by three common solids in natural water, i.e., biofilms, suspended particles and sediments. The effects of typical coexisting heavy metals on the sorption were also examined. The results show that the sorption is described by a dual-mode sorption model. Compared with sediments, more DDTs were sorbed by biofilms and suspended particles. Coexisting Pb, Cd and Cu increased the sorption of DDTs on sediments while decreasing the sorption on biofilms slightly, with little effect on the sorption on suspended particles. The different sorption behaviors of the solids were mainly determined by the composition of the solids: more organics were observed in biofilms and suspended particles. [ABSTRACT FROM AUTHOR]

In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2′-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1 × 10 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, with a wide linear working range from 2.0 × 10 to 1.0 × 10 mol/l. Due to the specific recognition of tetracycline by the MIP particles, the selectivity coefficients for routine interferences were less than 10. The fabricated electrode should be used in pH 2-4, response time of which was less than 200 s when the concentration of tetracycline was higher than 1.0 × 10 mol/l and no more than 30 min at the concentration of 1.0 × 10 mol/l. Finally, the proposed highly-sensitive ion selective electrode has been successfully applied to the determination of tetracycline in aqueous samples. [ABSTRACT FROM AUTHOR]

Cytochrome c (cyt- c) entrapped in agarose hydrogel was electrostatically bound to the edge plane pyrolytic graphite electrode (EPPGE), and then stable agarose-cyt- c/EPPGE was prepared. Direct electrochemistry between cyt- c and the EPPGE was monitored by protein film voltammetry. The effects of ionic strength, pH and exterior substances on the direct electrochemistry, and electrocatalytic properties of cyt- c were also studied. Results show that the electrochemical behavior of heme Fe(III)/Fe(II) in cyt- c is quasireversible. Its electrochemical performance is the best when the concentration of supporting electrolyte phosphate buffer solution is 0.2 mol/l and pH is 7.0, and greatly inhibited by exterior metal ions. Catalytic reduction of oxygen could also be achieved at the agarose-cyt- c/EPPGE. [ABSTRACT FROM AUTHOR]

A new xanthone derivative, 3,5,8-trihydroxy-2,2-dimethyl-3,4,4-trihydro-2 H,6 H-pyrano[3,2- b]-xanthen-6one ( 1), together with three known compounds, 5,8-dihydroxy-2,2-dimethyl-2 H,6 H-pyrano[3,2- b]xanthen6-one ( 2), cyclo-( N- O-methyl-L-Trp-L-Ile-D-Pip-L-2-amino-8-oxo-decanoyl) ( 3), and cyclo-(Phe-Tyr) ( 4), was isolated from the mangrove endophytic fungus No. ZSU-H16 obtained from the South China Sea coast. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Compound 1 exhibited cytotoxicity against KB and KBV 200 cells with IC50 values greater than 50 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new naphtho- γ-pyrone, 5-hydroxy-6,8-dimethoxy-2-benzyl-4H-naphtho[2,3-b]-pyran-4-one ( 1), together with three known compounds 5,7-dihydroxy-2-methylbenzopyran-4-one ( 2), 3,5-dihydroxy-2,7dimethylbenzopyran-4-one ( 3) and cyclo(Tyr-Tyr) ( 4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H26 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC50 values of 10 and 8 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

Abstract Purpose  This study evaluated the performance of the model for end-stage liver disease (MELD) in predicting post-transplant survival in a cohort of Chinese patients, and compared its predictive ability with that of the Child-Pugh score. Methods  The study enrolled 117 adult Chinese patients undergoing liver transplantation for benign end-stage liver diseases from January 1998 to January 2007 to evaluate the baseline characteristics and outcomes. Results  In a median follow-up duration of 90 weeks (range 0.2–373 weeks), 30 patients died. The 3-month and 1-year mortality rates of recipients in group 1 (MELD score 38) 91.7% and 91.7%, respectively. A statistical difference was observed in the mortality rates between the three groups (P P Conclusions  Both the MELD and Child-Pugh score are valid models to predict the short-term or mediumterm outcome of Chinese recipients undergoing liver transplantation for benign end-stage liver diseases. The MELD is superior to the Child-Pugh score in predicting the 3-month mortality post-transplantation. [ABSTRACT FROM AUTHOR]

A new polyketide, 2-(7′-hydroxyoxooctyl)-3-hydroxy-5-methoxybenzeneacetic acid ethyl ester ( 1), together with three known compounds dothiorelone A ( 2), B ( 3), and C ( 4) were isolated from the mangrove endophytic fungus Phomopsis sp. ZSU-H76 obtained from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR spectroscopic techniques. Primary bioassays showed that 1 exhibited cytotoxicity against HEp-2 and HepG2 cells with IC50 values of 25 and 30 μg/mL, respectively. [ABSTRACT FROM AUTHOR]

A new isoprenyl phenyl ether, 3-hydroxy-4-(3-methylbut-2-enyloxy)benzoic acid methyl ester ( 1), together with 4-hydroxybenzoic acid ( 2), 2-hydroxy-6-methylbenzoic acid ( 3), and 4-hydroxy-3-methoxybenzoic acid ( 4) were isolated from Mangrove fungus (No. B60) from the South China Sea. The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data. In the preliminary bioassay, compound 1 exhibited antibacterial and antifungal activities. Compound 1 also inhibited cytotoxicity to the hepG2 cell line with an IC50 value of 10.0 µg/mL. [ABSTRACT FROM AUTHOR]

IL6 is a pleiotropic cytokine which has been implicated in ligand-independent activation of androgen receptor in prostate cancer cells. Here, we present the evidence that two cytoplasmic kinases Pim1 and Etk are involved in this process. We showed that Pim1 is expressed in all prostate cancer cell lines examined. Both the expression level and the kinase activity of Pim1 are regulated by IL6 in these cells. Furthermore, we showed that IL6 downstream tyrosine kinase Etk can induce tyrosine phosphorylation of Pim1 which is correlated with its kinase activity. Mutation of the conserved Tyrosine 218 in the activation loop results in reduced kinase activity of Pim1. Interestingly, Etk can also be activated by Pim1 when they are coexpressed in prostate cancer cells, suggesting a possible positive feedback loop between Etk and Pim1. It appears that both Pim1 and Etk are required for IL6-induced activation of androgen receptor-mediated transcription in prostate cancer cells because overexpression of the kinase-deficient form of either Pim1 or Etk dramatically blocks the IL6 effect. Coexpression of the two kinases together but neither one alone is sufficient to activate ARE-containing promoter. Taken together, our data suggest a synergism of Ser/Thr kinase Pim1 and tyrosine kinase Etk in IL6 signaling and provide new insights into ligand-independent activation of androgen receptor in prostate cancer cells.Oncogene (2004) 23, 1838-1844. doi:10.1038/sj.onc.1207304 Published online 23 February 2004 [ABSTRACT FROM AUTHOR]

A new griseofulvin derivative, 7-chloro-2',5,6-trimethoxy-6'-methylspiro(benzofuran-2(3H),1'-(2) cyclohexene)3,4'-dione (1), together with the known 2-acetyl-7-methoxybenzofuran (2), was isolated from the marine-derived mangrove endophytic fungus Sporothrix sp. (No. 4335). The structure of new compound 1 was elucidated by analysis of spectroscopic data. [ABSTRACT FROM AUTHOR]

A new compound, β-sitosterylglucoside-3′- O-linoleate, named balanoinvolin, and three known compounds coniferin, methylconiferin, and 4- O- β-D-glucopyranosylconiferyl aldehyde, were isolated from Balanophora involucrate Hook. f. and their structures were determined by MS and 1D/2D NMR spectra. [ABSTRACT FROM AUTHOR]