Wolfsmilchgewächse (Euphorbiaceen) als nachwachsende Ressourcen der Oleochemie – Aktuelle bioorganische Analytik und prognostische Präventivtoxikologie

Species of Spurge (Euphorbiaceae) as Renewable Resources of Oleochemistry – Current Bioorganic Analytics and Prognostic Preventive Toxicology The botanical family of spurge (Euphorbiaceae) consists of about 8000 species. This reservoir of wild-type plants, an considerable number of which have economically interesting properties, may obtain significant importance in the search of renewable resources to replace currently used fossile resources. Therefore, for example, Euphorbia lathyris L., for instance, the herbaceous gopher plant or caper spurge, can be expected to became valuable because of the high oleic acid content in its seed. Plenty of problems, however, have to be solved on the way from a wild to a domesticated type, which can be cultivated in quantities as high as those of rape or sunflower. Trials to solve these problems as well as toxicological control are part of a multidisciplinary research program concerning Euphorbia lathyris L. (EULA), with the project “Renewable Raw Materials Program”, supported by the Federal Ministry of Agriculture (BMELF). Encouraging results have been achieved during the first years of research already, offering hope that mass cultivation of E. lathyris may become a realistic alternative for the production of oleic acid, but numerous problems still have to be solved.     

Support film in transmission electron microscopy: experiences with polyvinyl butyral Pioloform BM 18

Microscopic work with single-slot grids requires high-quality support films to span the relatively large gap. The imminent unavailability of the polyvinyl formal Pioloform FN 65, which to date has been used as the standard polyvinyl formal for the generation of support films in transmission electron microscopy (TEM), has necessitated the finding of a substitute material to produce such films. Therefore, we compared the polyvinyl butyral Pioloform BM 18 with the polyvinyl formal Pioloform FN 65 for the production of TEM support films, using operational criteria for assessment. Pioloform BM 18 with the solvent chloroform resulted in support films of unacceptable quality compared with Pioloform FN 65. Adding the softener dibutyl phthalate to the chloroform solvent for Pioloform BM 18 markedly improved the film quality, resulting in support films with high transparency and flexibility, and even greater stability in the electron beam when compared with films of Pioloform FN 65. Pioloform FN 65 also had the disadvantage of requiring highly toxic 1,2-dichloroethane as a solvent, whereas Pioloform BM 18 can be used with chloroform.     

Exposure to nephrotoxic ochratoxin A enhances collagen secretion in human renal proximal tubular cells

Ochratoxin A (OTA) is a nephrotoxic mycotoxin. There is evidence that OTA leads to cortical interstitial nephropathies in humans, associated with fibrosis. No data are available on the effect of OTA-induced collagen secretion from renal cortical cells. As kidney cortex mainly consists of proximal tubules, we investigated the effect of OTA on particular collagens (I, III, IV) in a well-established proximal tubular cell line (opossum kidney (OK) cells) and in primary cultured human renal proximal tubular epithelial cells (RPTECs). In fibroblasts, OTA neither exerted toxic effects nor induced collagen secretion, most probably due to the absence of suitable uptake mechanisms. OTA exerted time- and dose-dependent toxicity in both OK cells and human RPTECs. Moreover, OTA induced collagen secretion in a time- and dose-dependent manner in both cell types. In opposite to transforming growth factor beta1 (TGF-beta1), OTA incubation induced increased apical secretion of the basement membrane collagen IV. This might be evidence for a loss of cellular polarity after OTA incubation. We conclude that in proximal tubular cells, OTA is able to induce extracellular matrix deposition. As collagen secretion was also inducible in primary cultured human RPTECs, we hypothesize that OTA-induced extracellular matrix deposition by proximal tubular cells may be of importance in generation of renal diseases in humans which are under suspicion of being induced by OTA.     

Communication of intents among parents and their disturbed adolescent child.

Using 28 intact families, comparatively unstructured discussions between parents and their disturbed adolescent child concerning an important problem were assessed by means of a coding system designed to measure the intent of each communication made in the course of the interaction. Consistent differences were found between child behavior disturbance and parental verbal behavior when the families were divided into subgroups according to the adolescents' manifest style of problem expression. Findings support the view that there are consistent relationships between different patterns of familial behavior and the symptoms of the adolescent child. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sind "Biomedizin" und "Bioethik" behindertenfeindlich?

Ethik in der Medizin - Zwischen Medizinethik und Behindertenbewegung besteht Uneinigkeit darüber, ob von einer Diskriminierung von behinderten Menschen durch biomedizinische Verfahren, wie der...     

Electron Microscopy Study of γ-Al2O3 Supported Cobalt Fischer–Tropsch Synthesis Catalysts

Three supported catalysts containing 20 wt% cobalt and 0.5 wt% rhenium were subjected to electron microscopy studies in their calcined state. The catalysts were prepared by incipient wetness impregnation of γ-Al₂O₃ supports of different pore characteristics with aqueous solutions of cobalt nitrate hexahydrate and perrhenic acid. The influence of the support on the Co₃O₄ crystallite size and distribution was studied by X-ray diffraction and electron microscopy. There was a positive correlation between the pore diameter of the support and the post calcination Co₃O₄ crystallite size. On all three γ-Al₂O₃ supports, Co₃O₄ was present as aggregates of many crystallites (20–270 nm in size). Cobalt oxide did not crystallise as independent crystallites, but as an interconnected network, with a roughly common crystallographic orientation, within the matrix pore structure. The internal variations in crystallite size between the catalysts were maintained after reduction. Fischer–Tropsch synthesis was carried out in a fixed-bed reactor at industrial conditions (T = 483 K, P = 20 bar, H₂/CO = 2.1). Although the cobalt-time yields varied significantly (4.6–6.7 × 10^?3 mol CO/mol Co s), the site-time yields were constant (63–68 × 10^?3 s^?1) for the three samples. The C₅₊ selectivity could not be correlated to the cobalt oxide aggregate size and is more likely related to the cobalt particle size and chemical properties of the γ-Al₂O₃ support.