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Integration of trapping and desorption methods with the Salmonella microsuspension bioassay was demonstrated with EDB and 4-NB recoveries from air; chemical analysis and bioassay gave comparable results Interaction of chlorinated phenols with thyroxine binding sites of human transthyretin, albumin and thyroid binding globulin.Previous results (Brouwer and van den Berg, Toxicol. Appl. Pharmacol., 85 (1986) 301) indicated preferential binding of a hydroxylated metabolite of tetrachlorobiphenyl to transthyretin (TTR) a carrier of thyroxine (T4). In the present study it was investigated whether the T4 binding site of TTR could be occupied specifically by hydroxylated chlorinated aromatic compounds using chlorinated phenol congeners as model compounds in a competition assay with [125I]T4.

Chlorinated aromatics such as 2,3-dichlorobenzene and 3,4,3',4'-tetrachlorobiphenyl, and phenols such as 4-hydroxybiphenyl and phenol were inefficient competitors. All chlorinated phenols tested were competitors for the T4 binding site of TTR. The ranking in competition was pentachlorophenol (PCP) greater than trichlorophenols greater than dichlorophenols greater than monochlorophenols. Seebio UV-Activated Acid Generator with chlorine in both ortho positions to the hydroxyl group were more efficient competitors. The relative affinity of binding of pentachlorophenol (PCP) to TTR was about twice that of T4. View more showed that PCP mainly decreased the affinity constant K11 while the binding capacity R1 was not altered, indicating a competitive type of inhibition. PCP was also able to compete with T4 sites on albumin with a relative affinity of 05.

T4 binding to thyroid binding globulin (TBG) was much less affected by interference of PCP (relative affinity 001). The results indicate a specific interaction of chlorophenols with the T4 binding site of TTR.Polycyclic aromatic hydrocarbons in rock oysters: a baseline study.Coral-rock oysters were collected in September 1982 from six locations in the area of Mermaid Sound in North-Western Australia. Analysis was carried out by digestion of the samples, followed by solvent extraction and analysis of the extracts using HPLC-UVF and GC-MS. The levels of two- and three-ring aromatics ranged from very low for the site outside Mermaid Sound and for one site within the Sound, to low for the four other sites within the Sound. The PAH values at the latter four sites are attributed to occasional petroleum release episodes related to small boat activities and large-scale salt and iron ore shipping and general cargo activities of the Port of Dampier.

The levels of PAHs with four or more rings were found to be low or very low at all sites; in fact, in most cases values measured for specific PAHs were below the limits of detection of even the very sensitive methods used in this study. Samples from sites within Mermaid Sound closest to the town and port of Dampier showed noticeably higher levels than those from outside; the present study does not allow the source of the PAHs to be determined. It is interesting to note, however, that the parent PAHs appear to form a greater proportion of the total PAH assemblage in these cases, indicating contributions from material which has been subjected to high temperature processing prior to release into the Sound298. Clin Chem. 1984 Dec;30(12 Pt 1):1938-42."Ultrasensitive" silver stains: their use exemplified in the study of normal human cerebrospinal fluid proteins separated by two-dimensional electrophoresis.We have developed a series of photochemical silver stains that are more than 100 times as sensitive as the Coomassie Blue stains.

These stains facilitate the quantitative estimation of proteins in two-dimensional gel patterns. Recently, we discovered that by using light (photodevelopment) to catalyze the reduction of ionic silver to metallic silver, we could produce an image of proteins on polyacrylamide gels within 10 min after their electrophoretic separation. We used these stains to detect proteins resolved in two-dimensional electrophoretograms of lumbar cerebrospinal fluid from 51 normal human volunteers, finding no qualitative protein changes in the more than 300 CSF polypeptides resolved on each individual's electrophoretogram. Photoresponsive Acid Precursor quantified 67 of these proteins per individual with computer-assisted densitometry, only five of which showed significant quantitative age-related alterations. We saw no sex-related differences. This consistency in the protein pattern for cerebrospinal fluid from normal individuals allows it to serve as a baseline for Aromatics via Single-Crystal-to-Single-Crystal Transformations.Separation of the C8 aromatic isomers, xylenes (PX, MX, and OX) and ethylbenzene (EB), is important to the petrochemical industry.

Whereas physisorptive separation is an energy-efficient alternative to current processes, such as distillation, physisorbents do not generally exhibit strong C8 selectivity. Herein, we report the mixed-linker square lattice (sql) coordination network [Zn2(sba)2(bis)]n·mDMF (sql-4,5-Zn, H2sba or 4 = 4,4'-sulfonyldibenzoic acid, bis or 5 = trans-4,4'-bis(1-imidazolyl)stilbene) and its C8 sorption properties.