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In the spring of 2003, there was an outbreak of the severe respiratory syndrome (SARS) in Hong Kong. Health concerns have thus triggered an increased and predominant use of various types of household cleansing agents such as triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol). However, it has been reported recently that triclosan could be photochemically converted to toxic 2,8-dichlorodibenzo-p-dioxin (2,8-Cl(2)DD) in the environment. It is therefore necessary to develop environmentally friendly methods for the treatment of triclosan. To this end, photocatalytic degradation of triclosan in aqueous solution was conducted using TiO(2) (Degussa P25) under irradiation of UV light (lambda365 nm). It was found that triclosan could be degraded by this approach. Hydrogen peroxide was added to enhance the degradation process, and the optimal initial hydrogen peroxide concentration for triclosan degradation was 0.005% (w/v). Product identification indicated that triclosan oxidation occurred at its phenol moiety and yielded quinone and hydroquinone intermediates. The formation of a dichlorophenol intermediate in triclosan degradation suggested bond-breaking of the ether linkage occurred during the process. Moreover, no chlorinated dibenzo-p-dioxin congener was detected. These findings confirm that the photocatalytic degradation of triclosan is an environmentally friendly process.

Soil and sediment collected in the vicinity of an open electronic waste disposal and recycling facility located in Guiyu, Guangdong, China, were analyzed for the levels of common polybrominated diphenyl ethers (PBDEs) by using soxhlet extraction and gas chromatography/mass spectrometry. The PBDEs were detected in the soil and sediment samples at levels of 0.26-824 ng/g (dry weight). The obtained isomer profiles of PBDEs from the two soil samples collected from different contamination sites were found to be similar to various technical formulations of fire retardant products.

This communication describes the facile synthesis of five novel berberine dimers and their strong affinities toward double-stranded DNA. These berberine dimers were synthesized in 37–84% yields from the reaction of berberrubine with dihaloalkanes of varying lengths, and fully characterized by HRMS and 1H NMR. Compared with the monomeric parent berberine, these dimers showed greatly enhanced binding affinities up to approximately 100-fold, with two double helical oligodeoxynucleotides, d(AAGAATTCTT)2 and d(TAAGAATTCTTA)2, which was investigated by means of fluorescence spectrometry.

The ferritin consists of a protein shell constructed of 24 subunits and an iron core. The liver ferritin of Sphyrna zygaena (SZLF) purified by column chromatography is a protein composed of eight ferritins containing varying iron numbers ranging from 400+/-20 Fe3+/SZLF to 1890+/-20 Fe3+/SZLF within the protein shell. Nature SZLF (SZLFN) consisting of holoSZLF and SZLF with unsaturated iron (SZLFUI) to have been purified with polyacrylamide gel electrophoresis (PAGE) exhibited five ferritin bands with different pI values ranging from 4.0 to 7.0 in the gel slab of isoelectric focusing (IEF). HoloSZLF purified by PAGE (SZLFE) not only had 1890+/-20 Fe3+/SZLFE but also showed an identical size of iron core observed by transmission electron microscopy (TEM). Molecular weight of approximately 21 kDa for SZLFE subunit was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Four peaks of molecular ions at mass/charge (m/z) ratios of 10611.07, 21066.52, 41993.16, and 63555.64 that come from the SZLFE were determined by matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF MS), which were identified as molecular ions of the ferritin subunit (M+) and its polymers, namely, [M]2+, [M]+, [2M]+, and [3M]+, respectively. Both SZLFE and a crude extract from shark liver of S. zygaena showed similar kinetic characteristics of complete iron release with biphasic behavior. In addition, a combined technique of visible spectrometry and column chromatography was used for studying ratio of phosphate to Fe3+ within the SZLFE core. Interestingly, this ratio maintained invariable even after the iron release, which differed from that of other mammal ferritins.

A capillary electrophoresis-ion trap mass spectrometry method with a time-segment program was developed to simultaneously analyze Ziagen and its phosphorylated metabolites such as carbovir monophosphate, carbovir diphosphate, and carbovir triphosphate. By using the time-segment program, the positively charged nucleoside analog and negatively charged nucleotides were separated and detected in a single electrophoretic run. The limits of detection were less than 2 micro M for all of the analytes. Calibration curves of the compounds showed excellent linearity over the range of 2-100 micro M. The capability of the method was demonstrated by analyzing Ziagen and its phosphorylated metabolites that were spiked in cellular extracts of human peripheral blood mononuclear cells at 20 micro M levels. Some endogenous nucleotides such as adenosine 5'-triphosphate, adenosine 5'-diphosphate, and adenosine 5'-monophosphate, were also detected in the cellular extracts.

A reversed-phase HPLC method was developed for analyzing sinigrin and gluconasturtiin in six vegetable and two Chinese herb samples. A gradient program and mobile phases using methanol and 0.05% trifluoroacetic acid containing 20 mM ammonium acetate allowed sufficient retention and separation of the glucosinolates in the sample extracts. Quadrupole time-of-flight tandem mass spectrometry in negative ion electrospray ionization was used to analyze the fractions collected from the HPLC elution to confirm the identification of the glucosinolates. The levels of sinigrin and gluconasturtiin in the vegetables and Chinese herbs were determined by using an external calibration method. Concentrations of gluconasturtiin in the Chinese herbs were more than 15 times higher than those of sinigrin. Detection limits were 18 nmol g(-1) for sinigrin and 4 nmol g(-1) for gluconasturtiin when 50 g of fresh vegetable was analyzed.

From the liver of fish Dasyatis akajei, ferritin has been isolated by thermal denaturation and ammonium sulfate fractionation and then further purified by anion exchange chromatography and gel exclusion chromatography. The molecular weight of the liver ferritin of D. akajei (DALF) was measured to be 400 kDa by PAGE. Moreover, SDS-PAGE experimentation indicates that protein shell of DALF consists of the H and L subunits with molecular weight of 18 and 13 kDa, respectively. Using isoelectric focusing with pH ranging from 5.0 to 6.0, the ferritin purified by the PAGE exhibited three bands with different pI values in the gel slab. Diameters of the protein shell and iron core were also investigated by transmission electron microscope and determined to be 10–12 nm and 5–8 nm, respectively. A kinetic study of DALF reveals that the rate of self-regulation of the protein shell rather than the complex surface of the iron core plays an important role in forming a process for iron release with mixed orders.

A method of capillary HPLC-high-resolution MS was developed for the trace analysis of ATP, GTP, dATP and dGTP. Dimetylhexylamine (DMHA) was used as ion-pairing agent for the HPLC retention and separation of the nucleotides and positive ion electrospray time-of-flight MS was used for the detection. The application of capillary HPLC allowed minimal usage of DMHA while providing excellent peak retention and resolution, which significantly reduced the ion suppression in electrospray ionization-MS analysis and thus increased the sensitivity. Adduct ions of nucleotides and DMHA were used as quantitative ions in order to achieve the best sensitivity. DMHA concentration at 5 mM in the aqueous mobile phase at pH 7 found to be the optimal conditions for the C18 capillary column. The method was applied to determine ATP level in cultured C6 glioma cells that were treated with toxic concentrations of Zn. The results showed that the cellular ATP level decreased from 2.7 pmol/cell (10% cell death) in average control cell samples to 0.36 pmol/cell as the concentration of Zn increased to 120 mg/l (35% cell death) in culture medium.

Background & Aims Solid tumors often become hypoxic, leading to activation of hypoxia-response genes. We investigated the effects of overexpression of the hypoxia response genes eIF5A2 in esophageal squamous cell carcinoma (ESCC). Methods We used quantitative real-time polymerase chain reaction and immunohistochemistry analyses to compare expression of eIF5A2 between paired ESCC samples and nontumor esophageal tissues, and fluorescence in situ hybridization to detect gene copy-number alterations. Luciferase reporter and chromatin immunoprecipitation assays were used to study interactions between eIF5A2 and hypoxia-inducible factor-1α ( HIF1α ). We determined the effects of eIF5A2 overexpression and knockdown in ESCC cell lines and growth of ESCC xenograft tumors in nude mice. Results Levels of eIF5A2 messenger RNA and protein were increased in >40% of ESCC samples compared with matched nontumor tissues, along with levels of HIF1α and vascular endothelial growth factor. Increased levels of EIF5A2 were significantly associated with ESCC metastasis to lymph nodes ( P P = .037), and shorter survival times of patients ( P eIF5A2 was detected in 35.14% of ESCC samples that overexpressed eIF5A2. Hypoxia increased expression of eIF5A2 4- to 8-fold in ESCC cell lines; we observed bidirectional regulation between eIF5A2 and HIF1α . Transient transfection of ESCC cell lines with eIF5A2 increased their migratory and invasive abilities and markers of the epithelial to mesenchymal transition, and eIF5A2 knockdown or HIFα inhibition reduced these. In mice, xenograft tumors grown from ESCC cells that expressed eIF5A2 formed tumors more rapidly than cells that expressed only vector (controls); they also expressed higher levels of HIF1α and vascular endothelial growth factor, and formed more microvessels than controls. Knockdown of eIF5A2 in ESCC cells with interfering RNAs reduced their growth as xenograft tumors in mice, particularly when mice were given docetaxel or cisplatin. Conclusions eIF5A2 is overexpressed by gene amplification or hypoxia in ESCCs, and associated with up-regulation of HIF1α, metastasis, and shorter survival times of patients. Increased expression of eIF5A2 increases metastasis and angiogenesis in ESCC via the HIF1α -mediated signaling pathway.

A stepwise strategy was developed to synthesize boronic acid functionalized magnetic carbon nanotubes (MCNTs) for highly specific enrichment of glycopeptides. The MCNTs were synthesized by a solvothermal reaction of Fe(3+) loaded on the acid-treated CNTs and modified with 1-pyrenebutanoic acid N-hydroxysuccinimidyl ester (PASE) to bind aminophenylboronic acid (APBA) via an amide reaction. The introduction of PASE could bridge the MCNT and APBA, suppress the nonspecific adsorption and reduce the steric hindrance among the bound molecules. Due to the excellent structure of the MCNTs, the functionalization of PASE and then APBA on MCNTs was quite simple, specific and effective. The glycopeptides enrichment and separation with a magnetic field could be achieved by their reversible covalent binding with the boronic group of APBA-MCNTs. The exceptionally large specific surface area and the high density of boronic acid groups of APBA-MCNTs resulted in rapid and highly efficient enrichment of glycopeptides, even in the presence of large amounts of interfering nonglycopeptides. The functional MCNTs possessed high selectivity for enrichment of 21 glycopeptides from the digest of horseradish peroxidase demonstrated by MALDI-TOF mass spectrometric analysis showing more glycopeptides detected than the usual 9 glycopeptides with commercially available APBA-agarose. The proposed system showed better specificity for glycopeptides even in the presence of non-glycopeptides with 50 times higher concentration. The boronic acid functionalized MCNTs provide a promising selective enrichment platform for precise glycoproteomic analysis.

An ion-paring HPLC–MS–MS method with positive ion mode electrospray ionization has been developed to simultaneously quantify Ziagen, carbovir monophosphate, carbovir diphosphate and carbovir triphosphate. N ′, N ′-Dimethylhexylamine was used as the ion-pairing agent. The presence of this ion-pairing agent allowed the retention and separation of the four compounds on a reversed-phase HPLC column as well as the detection of the nucleotides with positive ion mode electrospray ionization. The limits of detection were found to be better than 25 n M for all the analytes. Calibration curves of the analytes showed excellent linearity over the range of 25 n M to 5 μ M . The relative standard deviations and accuracies for replicate analyses of quality control samples were less than 15%. The method has been successfully applied to the analysis of these compounds in human liver cells treated with Ziagen.

The application of liquid chromatography/ion-trap mass spectrometry for simultaneous quantification of multiple drugs and detection of their metabolites for in vitro experiments was reported recently. In the current study, the use of these techniques was extended to in vivo pharmacokinetic (PK) studies of alpha-1a antagonists. In combination with limited time-point PK, greatly increased throughput was demonstrated for the in vivo screening and investigation of in vivo-in vitro correlation. In addition to quantitative analyses, the technique allowed simultaneous detection of major in vivo metabolites without having to reanalyze the plasma samples. The drugs were individually dosed in mice intravenously via tail vein injection and the blood samples were collected 5 min and 2 h after dosing. After the plasma samples for the different drugs had been prepared separately, they were pooled for cassette analysis. The concentrations of five test compounds in the plasma samples at 2 h ranged from 36-1062 ng/mL, whereas their 5-min plasma levels were similar. From the same cassette analysis, major metabolites in the samples were also detected simultaneously through the interpretation of full-scan mass spectra. The metabolite identification confirmed the results from a previous report that the major sites of metabolism are hydroxylation of the phenyl ring not bearing the alkylsulfonamide substitutent, piperidine N-dealkylation, and N-demethylation of the alkylsulfonamide group.

Chelerythrine exhibits pronounced antitumor and apoptosis activities. In order to provide insights into the molecular mechanism of its pharmacological effects, binding selectivity of chelerythrine to a series of single-base bulged DNA hairpins has been assayed by using spectrofluorometric technique. The results indicated that chelerythrine binds specifically to C- and T-bulge sites in DNA hairpins, while sanguinarine exhibits extremely weak binding selectivity to any single-base bulged DNA hairpins, although it has very similar structure with chelerythrine.

A novel molecular imprinting sensor based on TiO2 sol–gel layers embedding Cu(OH)2 was developed for protein recognition. Protein-imprinted TiO2 layers were prepared by liquid phase deposition (LPD) using lysozyme (Lys) as a template protein. The synthetic molecularly imprinted nanoparticles (MIPs) can catalyze o-phenylenediamine (OPDA) oxidation to produce fluorescence and color. Cu(OH)2 played a catalytic role in this reaction. The fluorescence intensity was related to the amount of MIPs, but has nothing to do with the imprinted protein. Taking advantage of this phenomenon, the imprinted protein can be detected using ELISA plates to fixed MIPs by OPDA oxidation. The fluorescence intensity at 568 nm (ex: 350 nm) was found to increase with increasing concentration of Lys. It was found that the limit of detection was 0.001 mg mL−1 with the fluorescent sensor and 0.04 mg mL−1 with the colorimetric sensor under optimized conditions. The results show that the MIPs reached saturated adsorption at 0.2 mg mL−1. Furthermore, the MIPs showed high selectivity compared to other tested proteins. In contrast, the fluorescence change of the non-imprinted TiO2@Cu(OH)2 was only small. The proposed method will be a useful platform for recognition of protein with high sensitivity and specificity.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) is known as a highly toxic environmental contaminant and poses potential risks to human and animal health. As a persistent organic pollutant, 2,3,7,8-TCDD is hard to metabolize and thus gets accumulated in the human and animal body. Literature reports on the metabolism study of 2,3,7,8-TCDD are rare. The traditional method of GC-MS for 2,3,7,8-TCDD analysis might not be amenable for the direct analysis of its polar metabolites. In this study, in vitro metabolism of 2,3,7,8-TCDD with rat liver microsomes by using LC-MS and MS/MS was investigated and two hydroxylated metabolites of 2,3,7,8-TCDD and four trichloro-dihydroxydibenzo-p-dioxins were identified from the direct LC-MS and MS/MS analyses of the incubated samples.

A novel carbazole derivative, N,N′-bis(9-ethyl-9H-carbazol-3-yl)-(ethane-1,2-diamine), has been synthesized by reacting 3-amino-9-ethylcarbazole with glyoxal and characterized by 1H NMR, infrared spectroscopy, elemental analysis and mass spectra. The strong fluorescence emission at 438 nm of the derivative is effectively and selectively quenched by Cr3+. A 1 : 1 complex is formed between the carbazole derivative and Cr3+ and their association constant is 1.4 × 104 L mol−1. The results indicate that the carbazole derivative can provide a rapid, selective and sensitive response to Cr3+ in a linear dynamic range 1.0–20 μmol L−1 with a limit of detection of 0.10 μmol L−1 at pH 7.4. Common interferent ions do not show any interference with the Cr3+ determination. It is anticipated that the carbazole derivative could be a good candidate probe and has potential application for Cr3+ determination.

A versatile, ultrasensitive chemiluminescent metalloimmunoassay method for detection of H1N1 influenza virus was designed by using silver nanoparticles as an anti-H1N1 labeling tag to strongly amplify the CL signal of luminol.

A kind of surface glycoprotein imprinting over magnetic Fe3O4@Au multifunctional nanofibers (NFs) was developed and investigated. Magnetic Fe3O4@Au nanoparticles (NPs) as the core materials were modified consecutively with aniline, 3-aminophenylboronic acid (APBA) and acrylic acid to introduce boronic acids and polymerizable double bonds. With horseradish peroxidase (HRP) as a glycoprotein template, thin protein-imprinted films were fabricated via radical induced graft copolymerization of monomers on the surface of the multifunctional NFs. Experimental results show that the magnetic multifunctional Fe3O4@Au NFs can not only direct the selective occurrence of imprinting polymerization, but also drive glycoprotein templates into the polymer through reversible covalent complex formation. The results show that the imprinted NFs reached saturated adsorption at 0.3 mg mL−1 within 90 min and exhibited significant specific recognition towards the template protein. Moreover, the molecularly imprinted polymers (MIPs) were used to electrochemically detect HRP with good linearity in the range of low concentrations from 0.01 to 0.30 mg mL−1 through molecular recognition of K3[Fe(CN)6] current response. The detection limit of this method was found to be 0.005 mg mL−1 (S/N = 3). The synthetic strategy paves the way for preparation of functional nanomaterials by molecular imprinting technique and direct detection of proteins in a more convenient, simpler and cheaper way.

Aconitine, hypaconitine, mesaconitine, bulleyaconitine and lappaconitine are Aconitum alkaloids that have been proved to be neurotoxic and cardiotoxic. A method with liquid–liquid extraction and liquid chromatography coupled with electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) was developed and validated for the quantification of the five Aconitum alkaloids in human urine. Upon the successful chromatographic separation, the alkaloids were determined by ion trap tandem mass spectrometry. The precursor and major product ions of aconitine at m/z 646 → 586, mesaconitine at m/z 632 → 572, hypaconitine at m/z 616 → 556, bulleyaconitine at m/z 644 → 586 and lappaconitine at m/z 585 → 535 were monitored in positive ion mode. Linear calibration curves were generated from 0.02–5 μg mL−1 with coefficients of greater than 0.99. The method was validated with the intra-day and inter-day precisions represented by relative standard deviation of less than 7% in urine, and the recoveries from spiked urine samples varied from 89.8% to 96.4% for lappaconitine, 87.4–96.3% for hypaconitine, 81.5–90.6% for mesaconitine, 82.6–90.0% for aconitine and 82.2–88.7% for aconitine. Stability of aconitine was assessed under acidic, neutral and alkaline conditions. Aconitine hydrolysis was not observed during the urine sample pretreatment under neutral and weak acidic conditions.

A simultaneous redox, alkylation, self-assembly reaction under solvothermal conditions afforded a novel copper(I) chain polymer constructed of luminescent Cu3I4- and unprecedented EtS-4-C5H4N+Et components (Et = CH3CH2).

A highly sensitive electrochemical immunoassay method for detection of H1N1 influenza virus with the signal amplification of CuO nanoparticles (NPs) has been demonstrated.

N-Phosphorylation labeling was utilized to analyze small metabolites using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS). The incorporation of a neutral phosphoryl group with high gas-phase proton affinity not only improved the ionization efficiency of the target molecules, but also greatly reduced the matrix background interference.

The arachidonic acid (AA) metabolic network produces key inflammatory mediators which have been considered as hallmark contributors in various inflammatory related diseases. Enzymes in this network, such as 5-lipoxygenase (5-LOX), cyclooxygenase (COX), leukotriene A(4) hydrolase (LTA4H) and prostaglandin E synthase (PGES), have been used as targets for anti-inflammatory drug discovery. Multi-target drugs and drug combinations have also been developed for this network. However, how the inhibitors alter the dynamics of metabolite production and which combinatorial target intervention solutions are better needs further exploration. We did a system based intervention analysis on the AA metabolic network. Using an LC-MS/MS method, we quantitatively studied the eicosanoid metabolites responses of AA metabolic network during stimulation of Sprague Dawley rat blood samples with the calcium ionophore. Our results indicate that inhibiting the upstream rather than the downstream target of 5-LOX pathway will simultaneously alter the AA metabolism to the COX pathway (and vice versa). Therefore, single-target inhibitors cannot control all the inflammatory mediators at the same time. We also suggest that in the case of multiple-target anti-inflammatory solutions, the combination of inhibitors of the downstream enzymes may have stronger inhibition efficiency and cause less side-effects compared to the other solutions. One therapeutic strategy, LTA4H/COX inhibition solution, was found promising for the intervention of inflammatory mediator biosynthesis and at the same time stimulating the production of anti-inflammatory agents.

In this paper, we developed a simple and effective on-line focusing technique combining dynamic pH junction and sweeping by capillary electrophoresis (CE) with laser-induced fluorescence (LIF) detection. Dynamic pH junction-sweeping is defined when the sample has a different buffer pH (dynamic pH junction condition) and is devoid of micelles (sweeping condition) relative to the background electrolyte (BGE). This hyphenated focusing mode was applied to the sensitive and selective focusing of four dipeptides: Tyr-Phe, Tyr-Leu, Trp-Gly, and Ala-Gln. Picomolar detectability of these dipeptides by CE-LIF detection was demonstrated through effective focusing of large sample volumes (up to 39% capillary length) using the dual pH junction-sweeping focusing mode. 25 mmol L(-1) sodium dihydrogen phosphate, pH 2.5 was used as the sample matrix, and 100 mmol L(-1) borate, 21 mmol L(-1) sodium dodecylsulfate (SDS), 16 mmol L(-1) Brij35, pH 9.0 as the background solution (BGS). The concentration detection limits (S/N = 3) of the four dipeptides were in the range of 1.0-5.0 pmol L(-1). The developed method has been successfully used for the determination of dipeptides in human serum samples.

A novel signal-on electrochemiluminescent (ECL) biosensor based on adenosine triphosphate (ATP)-induced recombination of split aptamer chips is presented.

A phenylboronate affinity monolith was prepared and applied to the selective capture of glycoproteins from unfractionated protein mixtures. The monolith was synthesized in a 100 μm i.d capillary by an in situ polymerization procedure using a pre-polymerization mixture consisting of 4-vinylphenylboronic acid (VPBA) as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker, diethylene glycol and ethylene glycol as binary porogenic solvents, and azobisisobutyronitrile (AIBN) as initiator. The prepared monolith was characterized in terms of the morphology, pore property, and recognition property. The selectivity and dynamic binding capacity were evaluated by using standard glycoproteins and nonglycoproteins as model proteins. The chromatographic results demonstrated that the phenylboronate affinity monolith had higher selectivity and binding capacity for glycoprotein than nonglycoprotein. The resulting phenylboronate affinity monolith was used as the sorbent for in-tube solid phase microextraction (in-tube SPME), and the extraction performance of the monolith was assessed by capture of ovalbumin from egg white sample.

A novel catalytic colorimetric assay assisted by nicking endonuclease signal amplification (NESA) was developed. With the signal amplification, the detection limit of the p53 target gene can be as low as 1 pM, which is nearly 5 orders of magnitude lower than that of other previously reported colorimetric DNA detection strategies based on catalytic DNAzyme.

An inorganic-organic hybrid affinity monolithic column was synthesized by a novel "one-pot" approach. The resulting hybrid affinity monoliths have potential applications in specific recognition and enrichment of glycoproteins.

Human hepatocellular carcinoma (HCC) is one of the most malignant tumors, being particularly induced by unregulated growth and metastasis, and is a leading cause of death and major health problems in many countries. We report here the identification of 167 differentially expressed proteins between HCC (MHCC97-H) cells and Chang liver cells using enhanced nano-liquid chromatography/mass spectrometry (LC/MS). The most relevant pathways of differentially expressed proteins are involved in cytoskeleton organization, stress defense, and energy homeostasis etc. Moreover, of the identified proteins, there are 59 known or putative membrane-associated proteins with multitransmembrane domains confirmed by bioinformatic analysis. These proteins may be associated with cancer, reflecting tumorigenesis of HCC, and would be useful for the development of diagnostic and subsequently pharmaceutical targets of HCC. In addition, we identify a total of 41 proteins that are found to be up- or down-regulated following tanshinone IIA treatment for MHCC97H cells in a time-depended manner. Also, several proteins that are involved in actin cytoskeleton and stress resistance are mainly down-regulated, whereas proteins associated with cell redox homeostasis, mitochondrial, and microtubule-based movement are identified as mostly up-regulated after the treatment. Determination of functional roles of those differentially expressed proteins will enable further understanding of the mechanism of HCC tumorigenesis and exploration of new drugs for therapeutic intervention.

The data on PCDD/F emissions appearing in the Abstract and in the Results and discussion section titled “Polychlorinated dibenzo-p-dioxins and dibenzofurans as a result of open burning” on pages 21 and 29, respectively, of Vol. 8 (2006), No.1, were published as a result of miscommunication and with insufficient attribution. The original source and correct concentrations can be found in an article by Brian K. Gullet, William P. Linak, Abderrahmane Touati, Shirley J. Wasson, Staci Gatica, and Charles K. King, to be published in the Journal of Material Cycles and Waste Management, Vol. 9 (2007), No. 1.

A soluble 2,3,9,10-tetrakis(trimethylsilyl)pentacene (1) was synthesized; the discovery of the radical cationic character of 1 in solution through EPR measurement has provided insights into the sensitivity of acenes towards light and oxygen.