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The solvent 1,3-dichlorobenzene (1,3-DCB) is formed during thermal decomposition of the initiator 2,4-dichlorobenzoylperoxide in the production of silicone rubber with potential exposure of production workers as shown in previous works. Despite a threshold limit value (MAK value) of 2 ppm in air, there are currently no data about the corresponding internal exposure that would allow for the derivation of a biological limit value. In the present study, we have investigated the absorption of 1,3-DCB and urinary kinetics of its metabolites in 10 human volunteers after controlled inhalative exposure. Due to the strong odour of 1,3-DCB, a subjective evaluation of odour nuisance was also performed. Ten male human volunteers (23–36 yrs.) were exposed 6 h/day to a concentration of 0.7 ppm and 1.5 ppm in the Aachen workplace simulation laboratory (AWSL) with one week between each experiment. In order to investigate potential dermal absorption, the volunteers were exposed to 1.5 ppm wearing a suitable filter mask that prevented inhalative exposure in a third exposure. 1,3-DCB in blood was measured after 3 and 6 h exposure and the urinary metabolites 3,5-dichlorocatechol (3,5-DCC), 2,4-dichlorophenol (2,4-DCP) and 3,5-dichlorophenol (3,5-DCP) were measured over 24 h after exposure via LC/MS/MS. There were clear dose–response relations for all investigated parameters. The maximum excretion of the metabolites was reached at the end of exposure and corresponded to 5.2 ± 0.7 mg/g crea, 1.5 ± 0.35 mg/g crea and 0.07 ± 0.011 mg/g crea at 0.7 ppm and to 12.0 ± 3 mg/g crea, 3.5 ± 1.1 mg/g crea and 0.17 ± 0.05 mg/g crea at 1.5 ppm for 3,5-DCC, 2,4-DCP and 3,5-DCP, respectively. The use of filter masks decreased the internal exposure for about 85–90%, indicating substantial dermal absorption. Odour perception did not show a dose–response, probably due to fast olfactory adaption. The human study presented here provides an excellent basis for deriving a biological limit value for 1,3-DCB. [ABSTRACT FROM AUTHOR]

Combination treatment with the clotting factors recombinant activated factor VII (rFVIIa), serine protease, and recombinant factor XIII (rFXIII), protransglutaminase, is being explored for haemostatic therapy. We performed a single-dose toxicology study in the cynomolgus monkey, with four dose groups receiving 0.1 + 0.34 mg kg-1 (group 1), 0.33 + 1.12 mg kg-1 (group 2), 1.67 + 5.60 mg kg-1 (group 3) and 5.00 + 16.80 mg kg-1 (group 4) of a rFVIIa + rFXIII combination. In the three lower dose groups, no clinical, histopathological or blood chemistry changes were observed. In group 4, the animals died at 4 h post-dosing, with histopathology revealing a systemic coagulopathy resembling, but distinct from, disseminated intravascular coagulation. Due to the absence of toxicity warning signs, toxicity biomarkers were identified by a Western blot-based screening of approximately 20 plasma proteins known to be involved in the clotting cascade. Three of the examined proteins were specifically affected by rFVIIa + rFXIII treatment. Fibronectin and fibrinogen exhibited dose-dependent reductions from less than 10% reduction (group 2) to more than 90% reduction (group 4). These reductions were reversible, and specific. For vitronectin, a dose-dependent conversion to the 65-kDa form was found to occur in groups 3 and 4. Thus, fibrinogen, fibronectin and vitronectin represent the first biomarkers for clotting factor toxicity. [ABSTRACT FROM AUTHOR]

Many natural resources are inefficiently used in advanced western economies. Overuse of common property resources such as air occurs. The assignment of property rights through grandfathering established uses can have disincentive effects as an entry barrier to new industry and allow the continuation of pernicious uses. A Henry George type alternative remedial system of legal and tax treatment is developed It systematically covers all natural resources and their deteriorations. as well as improvements. This updating will be extremely useful to everyone concerned with ecology. Also the task of industrial siting can be accomplished so as to ensure an efficient use of natural resources. Present problems of dealing with pollution and hazardous waste sites under tort law would he avoided. This part of the two-part paper covers the application of the theory. The last issue of this Journal presented the basic theoretical considerations. [ABSTRACT FROM AUTHOR]

Many natural resources are inefficiently used in advanced western economies Overuse of common property resources such as air occurs The assignment of property rights through grandfathering established uses can have disincentive effects as an entry barrier to new industry and allow the continuation of pernicious uses A Henry George type alternative remedial system of legal and tax treatment is developed It systematically covers all natural resources and their deteriorations, as well as improvements This updating should be extremely useful to everyone concerned with ecology. Also the task of industrial siting can be accomplished so as to ensure an efficient use of natural resources Present problems of dealing with pollution and hazardous waste sites under tort law would be avoided This part of the two-part paper covers the basic theoretical considerations The next issue of this Journal will include the application of the theory [ABSTRACT FROM AUTHOR]

A calcified thrombus resembling a staghorn was found in the aortic arch, cast into this shape by the aorta and its branching vessel, the left subclavian, into which it projected for a short distance. Unique, in this case, is the extraordinarily large size of the calcification which was mostly free of the vessel wall, its radiological image, and its location. Digital subtraction angiography led to the diagnosis and was confirmed on computed tomography. [ABSTRACT FROM AUTHOR]