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Background: Plasma concentration of retinol is an accepted indicator to assess the vitamin A (retinol) status in cattle. However, the determination of vitamin A requires a time consuming multi-step procedure, which needs specific equipment to perform extraction, centrifugation or saponification prior to high-performance liquid chromatography (HPLC)., Methods: The concentrations of retinol in whole blood (n = 10), plasma (n = 132) and serum (n = 61) were measured by a new rapid cow-side test (iCheck™ FLUORO) and compared with those by HPLC in two independent laboratories in Germany (DE) and Japan (JP)., Results: Retinol concentrations in plasma ranged from 0.033 to 0.532 mg/L, and in serum from 0.043 to 0.360 mg/L (HPLC method). No significant differences in retinol levels were observed between the new rapid cow-side test and HPLC performed in different laboratories (HPLC vs. iCheck™ FLUORO: 0.320 ± 0.047 mg/L vs. 0.333 ± 0.044 mg/L, and 0.240 ± 0.096 mg/L vs. 0.241 ± 0.069 mg/L, lab DE and lab JP, respectively). A similar comparability was observed when whole blood was used (HPLC vs. iCheck™ FLUORO: 0.353 ± 0.084 mg/L vs. 0.341 ± 0.064 mg/L). Results showed a good agreement between both methods based on correlation coefficients of r 2  = 0.87 (P < 0.001) and Bland-Altman blots revealed no significant bias for all comparison., Conclusions: With the new rapid cow-side test (iCheck™ FLUORO) retinol concentrations in cattle can be reliably assessed within a few minutes and directly in the barn using even whole blood without the necessity of prior centrifugation. The ease of the application of the new rapid cow-side test and its portability can improve the diagnostic of vitamin A status and will help to control vitamin A supplementation in specific vitamin A feeding regimes such as used to optimize health status in calves or meat marbling in Japanese Black cattle.

Background: Rhizaria are a major branch of eukaryote evolution with an extensive microfossil record, but only scarce molecular data are available. The rhizarian species Reticulomyxa filosa, belonging to the Foraminifera, is free-living in freshwater environments. In culture, it thrives only as a plasmodium with thousands of haploid nuclei in one cell. The R. filosa genome is the first foraminiferal genome to be deciphered., Results: The genome is extremely repetitive, and the large amounts of identical sequences hint at frequent amplifications and homologous recombination events. Presumably, these mechanisms are employed to provide more gene copies for higher transcriptional activity and to build up a reservoir of gene diversification in certain gene families, such as the kinesin family. The gene repertoire indicates that it is able to switch to a single-celled, flagellated sexual state never observed in culture. Comparison to another rhizarian, the chlorarachniophyte alga Bigelowiella natans, reveals that proteins involved in signaling were likely drivers in establishing the Rhizaria lineage. Compared to some other protists, horizontal gene transfer is limited, but we found evidence of bacterial-to-eukaryote and eukaryote-to-eukaryote transfer events., Conclusions: The R. filosa genome exhibits a unique architecture with extensive repeat homogenization and gene amplification, which highlights its potential for diverse life-cycle stages. The ability of R. filosa to rapidly transport matter from the pseudopodia to the cell body may be supported by the high diversification of actin and kinesin gene family members., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In September of 1869, while studying sponges off the Norwegian island of Gisoe, Ernst Haeckel (1834-1919) discovered a tiny, flagellated ball-shaped organism swimming about in his samples. Appearing first to be the planula larva of an invertebrate marine animal further observation revealed it to be a colony of flagellated cells with a complex life cycle transitioning between multicellular and single-cell stages and several distinct forms of protozoa. Haeckel named it Magosphaera planula (the "magician's ball") and it eventually assumed a central role in his theories of animal evolution, appearing as the modern exemplar of the blastaea stage in his gastraea theory of metazoan evolution. Throughout the latter half of the nineteenth century and into the twentieth it was an object of considerable scientific interest, and yet it was only ever observed by Haeckel himself and then only the once. Eventually it faded altogether from scientific discussion. This paper traces the rise and fall of Magosphaera as an important epistemic object in the theories of Haeckel and other biologists, and an attempt is made to identify what exactly the organism (or organisms!) was that Haeckel observed in the fall of 1869.