Photoactivation of pheophorbide a induces a mitochondrial-mediated apoptosis in Jurkat leukaemia cells.

The mechanism of cell death by pheophorbide a (Pba) which has been established to be a potential photosensitizer was examined in experimental photodynamic therapy (PDT) on Jurkat cells, a human lymphoid tumor cell line. In 30-60 min after irradiation, Pba treated cells exhibited apoptotic features including membrane blebbing and DNA fragmentation. Pba/PDT caused a rapid release of cytochrome c from mitochondria into the cytosol.

Size-based analysis of incinerator fly ash using gravitational SPLITT fractionation, sedimentation field-flow fractionation, and inductively coupled plasma-atomic emission spectroscopy.

Fly ash has been regarded as hazardous because of its high adsorption of toxic organic and/or inorganic pollutants. Fly ash is also known to have broad distributions of different chemical and physical properties, such as size and density. In this study, fly ash emitted from a solid waste incinerator was pre-fractionated into six sub-populations by use of gravitational SPLITT fractionation (GSF).

Polychlorinated dibenzo-p-dioxins and dibenzofurans from food salt samples processed by heat treatment in Korea.

Eight samples of processed food salt collected from five plants in Korea were analyzed for 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) using liquid-liquid extraction, clean-up procedures, and high resolution gas chromatography-high resolution mass spectrometry. The study included the analyses of two kinds of salt product sample: bamboo-salt and parched salt. The levels of toxic PCDD/Fs found in the salt product samples were extremely low: the results revealed TEQ levels ranging between the sub pg TEQ/g and sub fg TEQ/g.

Size analysis of industrial carbon blacks by sedimentation and flow field-flow fractionation.

Carbon black is one of the most useful particulate materials in the industrial field. Among the various physical properties of carbon black, size and size distribution are the most important properties to affect the quality of a final product. However, it is difficult to measure the exact particle size of carbon black since it suffers unavoidable interference from flocculation.

Comparison of separation conditions and ionization methods for the liquid chromatography-mass spectrometric determination of sulfonamides.

The effects of the type and concentration of buffer, composition of the mobile phase and the ionization mode, used for the separation and detection of sulfonamides with LC-MS, were studied. Five typical sulfonamides were selected as target compounds and beef meat was selected as a matrix sample. For the separation of sulfonamides, 0.

Probing lysine acetylation with a modification-specific marker ion using high-performance liquid chromatography/electrospray-mass spectrometry with collision-induced dissociation.

Posttranslational acetylation of proteins regulates many diverse functions, including DNA recognition, protein-protein interaction, and protein stability. The identification of enzymes that regulate protein acetylation has revealed broader use of this modification than was previously suspected. In this study, we describe a method for identifying protein acetylation at lysine residues by analysis of digested protein using HPLC/ESI-MS with a new modification-specific marker ion.

Size characterization of incinerator fly ash using sedimentation/steric field-flow fractionation.

Fly ash particles emitted from municipal solid waste-incinerators are of environmental concern. This study aims to investigate the applicability of sedimentation/steric field-flow fractionation (Sd/StFFF) and to develop a Sd/StFFF method for the separation and size characterization of incinerator fly ash. This study focuses on the fly ash particles larger than approxiamtely 1 microm, which comprise more than 90% (w/w) of the fly ash.