Developmental Toxicity and Biotransformation of Two Anti-Epileptics in Zebrafish Embryos and Early Larvae

The zebrafish (Danio rerio) embryo is gaining interest as a bridging tool between in-vitro and in-vivo developmental toxicity studies. However, cytochrome P450 (CYP)-mediated drug metabolism in this model is still under debate. Therefore, we investigated the potential of zebrafish embryos and larvae to bioactivate two known anti-epileptics, carbamazepine (CBZ) and phenytoin (PHE), to carbamazepine-10,11-epoxide (E-CBZ) and 5-(4-hydroxyphenyl)-5-phenylhydantoin (HPPH), respectively. First, zebrafish were exposed to CBZ, PHE, E-CBZ and HPPH from 5¼- to 120-h post fertilization (hpf) and morphologically evaluated. Second, the formations of E-CBZ and HPPH were assessed in culture medium and in whole-embryo extracts at different time points by targeted LC-MS. Finally, E-CBZ and HPPH formation was also assessed in adult zebrafish liver microsomes and compared with those of human, rat, and rabbit. The present study showed teratogenic effects for CBZ and PHE, but not for E-CBZ and HPPH. No HPPH was detected during organogenesis and E-CBZ was only formed at the end of organogenesis. E-CBZ and HPPH formation was also very low-to-negligible in adult zebrafish compared with the mammalian species. As such, other metabolic pathways than those of mammals are involved in the bioactivation of CBZ and PHE, or, these anti-epileptics are teratogens and do not require bioactivation in the zebrafish.     

Functional Properties of Pork Liver Protein Fractions

The functional (emulsifying, gelling and foaming) properties of liver protein fractions as well as their molecular weight distribution and surface hydrophobicity were investigated and compared to commercial proteins. Two protein fractions were characterized: water soluble (WSLP) and WSLP combined with salt soluble liver proteins (W?+?SSLP). The effect of salt concentrations was also investigated (0, 1.8 and 3.4 % NaCl). Both WSLP and W?+?SSLP displayed good emulsifying properties and foam stability. However, their gelling properties were rather poor. An increase in salt concentration decreased the emulsifying properties of WSLP while the effect on W?+?SSLP was less pronounced. Addition of 1.8 % NaCl increased foaming ability of WSLP and W?+?SSLP while foam stability was not affected. Further increase of NaCl (3.4 %) decreased both foaming ability and foam stability and is probably attributed to refolding of the protein molecules because of the higher level of hydrophobic groups with 3.4 % NaCl. Gel forming ability of WSLP and W?+?SSLP containing 0 % was higher compared to high salt concentrations. However, higher salt concentrations shifted onset gelation temperature of WSLP and W?+?SSLP to lower temperatures probably due to partial unfolding of the proteins as indicated by an increase of the surface hydrophobicity.     

Induced Mood Change and Dysfunctional Attitudes in Remitted Bipolar I Affective Disorder.

This study investigated the possibility that, in remitted bipolar I affective disorder, dysfunctional attitudes are mood-state dependent. Participants were 120 individuals with remitted bipolar I disorder, remitted unipolar depression, or no history of affective disorder. The Dysfunctional Attitudes Scale (DAS; Weissman, 1979) was completed before and after positive or negative mood challenge. Following mood increase, the bipolar group changed significantly less in DAS total score than did the other 2 groups, and in goal-striving and achievement attitudes relative to the unipolar group. These findings did not provide clear support for the mood-state dependency theory in bipolar disorder, arguing instead for the presence in bipolar I disorder of dysfunctional cognitions that show characteristic resilience in the face of minor positive mood increase. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Triacylglycerol Analysis of Fats and Oils by Evaporative Light Scattering Detection

A high performance liquid chromatography method with evaporative light scattering detection was developed for the analysis of oils and fats, which enabled excellent separation of major and minor triacylglycerol (TAG) species in 33 min, including regeneration of the column. The influence of the mobile phase and temperature on separation and analysis time were evaluated with a cocoa butter standard. The influence of the drift tube temperature and flow of the nebulising gas on the evaporative light scattering detector output signal was investigated by means of a response surface experimental design. Especially the flow of the nebulising gas had a profound effect on the detector signal. An optimal separation was obtained when using a 150 × 3.0 mm C18 column with 3 μm particle diameter at 20 °C and an acetonitrile/dichloromethane gradient at 0.72 mL/min. The maximum response was attained when the ELSD detector was set at the minimum temperature (45 °C) and a gas flow of 1.2 L/min. Finally, the linearity of the detector was investigated. It was found that at very low concentrations, the signal tends to flatten towards zero, giving an underestimation for minor TAG species, especially for oils or fats with a mixed fatty acid composition.     

Production of cocoa butter substitutes <Emphasis Type="Italic">via</Emphasis> two-stage static fractionation of palm kernel oil

As are traditional fractionation technologies, static dry fractionation is a highly reliable technology for the consistent production of good-quality palm kernel stearin (PKS) for use as cocoa butter substitute (CBS) after total hydrogenation. A new process route now permits the production of unhardened yet high-quality CBS. Also an increase in total stearin yield can be achieved, via a successful refractionation of palm kernel olein. DSC analysis together with pilot static fractionation trials on the palm kernel olein indicates that a cooling water temperature that is too low (e.g., 17°C) may result in the quick formation of unstable crystals that are possibly later converted to a more stable form. The resulting mixture of crystals with a possibly different polymorphic structure is easily squeezed through the filter cloth during filtration, whereas a slower, but more homogeneous co-crystallization occurs at higher temperature (18°C or higher) and results in a much more stress-resistant slurry. Polarized light microscopy analysis confirmed that crystal size is not the only determining factor for a successful filtration. The total two-stage static fractionation of palm kernel oil (PKO) [iodine value (IV) 18] on a pilot scale results in the following three end products: PKS IV 5 (yield: 29%, for direct use as CBS), PK olein IV 27 (yield: 58%), and PKS IV 7 (yield: 13% for use as CBS after full hydrogenation). The unhardened PKS IV 5 has outstanding melting and crystallization properties, comparable to traditional hydrogenated stearin fractions. Therefore, rather than the higher stearin yield, the reduced hydrogenation capacity is most probably the most important benefit of the two-stage static fractionation process.     

Selective List of Recent Dress Exhibitions

Abstract

This list includes temporary exhibitions and new permanent displays mounted in UK museums and galleries during 2012. Each display contained at least some items of dress or dress fabrics, fashion plates or fashion photography.