Die Bionik der Schwungfederkaskade

Bionics of the primary cascade – solution of an optimization problem Investigating of the properties of the primary cascade in soaring birds to date resulted in some spectacular insights. It was disclosed that the primary cascade with its staggered feathers acts like a vortex diffusor and, hence, considerably reduces the wing drag. That advance enlarges the range in migration and food sourcing. Newly the reason for the circular respectively spherical positioning of the primary tips could be resolved. This spatial arrangement features an optimum with respect to enlarging the distances of the feather tips and span, respectively, at limited root bending moments at once. This synergistic solution leads to an optimized fracture behavior and favors the lightweight construction of avian wings.     

Polypeptide composition of rat high density lipoprotein: characterization by SDS-gel electrophoresis

The histones synthesized by three different interspecies hybrid echinoid embryos have been examined. In all three crosses, the species-specific F1 histone of the paternal parent is found in the chromatin of the hybrid. These findings provide direct evidence for the involvement of newly transcribed mRNA in the synthesis of this protein. F1 histone is a unique protein in that it is the only paternal protein detected in these hybrids. The possibility that the synthesis of histones is controlled differently from that of other proteins is discussed.     

Zerfurchte Flügel und zähe Luft

Corrugated wings and viscous air Airborne microorganisms were bound to evolve morphologic characteristics that are optimized with respect to their scale regime. Vortices – stationary or dynamically generated – herein are playing a dominant role. The generation of vortices in microorganisms is assisted by micro-morphologic structures as veins, grooves and pores.     

Signature lipids and stable carbon isotope analyses of Octopus Spring hyperthermophilic communities compared with those of Aquificales representatives.

The molecular and isotopic compositions of lipid biomarkers of cultured Aquificales genera have been used to study the community and trophic structure of the hyperthermophilic pink streamers and vent biofilm from Octopus Spring. Thermocrinis ruber, Thermocrinis sp. strain HI 11/12, Hydrogenobacter thermophilus TK-6, Aquifex pyrophilus, and Aquifex aeolicus all contained glycerol-ether phospholipids as well as acyl glycerides. The n-C(20:1) and cy-C(21) fatty acids dominated all of the Aquificales, while the alkyl glycerol ethers were mainly C(18:0). These Aquificales biomarkers were major constituents of the lipid extracts of two Octopus Spring samples, a biofilm associated with the siliceous vent walls, and the well-known pink streamer community (PSC). Both the biofilm and the PSC contained mono- and dialkyl glycerol ethers in which C(18) and C(20) alkyl groups were prevalent. Phospholipid fatty acids included both the Aquificales n-C(20:1) and cy-C(21), plus a series of iso-branched fatty acids (i-C(15:0) to i-C(21:0)), indicating an additional bacterial component. Biomass and lipids from the PSC were depleted in (13)C relative to source water CO(2) by 10.9 and 17.2 per thousand, respectively. The C(20-21) fatty acids of the PSC were less depleted than the iso-branched fatty acids, 18.4 and 22.6 per thousand, respectively. The biomass of T. ruber grown on CO(2) was depleted in (13)C by only 3.3 per thousand relative to C source. In contrast, biomass was depleted by 19.7 per thousand when formate was the C source. Independent of carbon source, T. ruber lipids were heavier than biomass (+1.3 per thousand). The depletion in the C(20-21) fatty acids from the PSC indicates that Thermocrinis biomass must be similarly depleted and too light to be explained by growth on CO(2). Accordingly, Thermocrinis in the PSC is likely to have utilized formate, presumably generated in the spring source region.     

Reinitiation of cell division and polyamine and aromatic monoamine levels in alfalfa explants during the induction of somatic embryogenesis

The early cellular events in leaf explants of Medicago sativa L. cultured on somatic embryogenesis- and callogenesis-inducing media (EIM and CIM, respectively) were correlated with the endogenous contents of polyamines (PAs) and aromatic monoamines (AMs). On the second day of culture, replication of DNA occurred in epidermal and subepidermal cells on the edges of explants on EIM and was a prerequisite for proembryonal mass and, later, globular proembryo formation. In explants cultured on CIM, replication occurred at least one day later and in fewer cells, which were randomly spread all over the explant. Transition of leaf explant cells to rapidly dividing meristematic-like cells on EIM or to enlarged, highly vacuolated cells on CIM was observed. The increase in total PA levels in cultured explants was primarily a consequence of increases in putrescine (Put) and spermidine (Spd) contents and was much more pronounced on EIM than on CIM. High Spd levels were characteristic of meristematic cells and might be essential for the development of globular structures. The higher amount of insoluble PA conjugates was determined in explant cells on EIM, as compared with CIM. Proembryogenic cell mass formation was positively correlated with free tyramine and negatively correlated with free phenylethylamine contents.     

Archaeosomes made of Halorubrum tebenquichense total polar lipids: a new source of adjuvancy

Background  

Archaeosomes (ARC), vesicles prepared from total polar lipids (TPL) extracted from selected genera and species from the Archaea domain, elicit both antibody and cell-mediated immunity to the entrapped antigen, as well as efficient cross priming of exogenous antigens, evoking a profound memory response. Screening for unexplored Archaea genus as new sources of adjuvancy, here we report the presence of two new Halorubrum tebenquichense strains isolated from grey crystals (GC) and black mood (BM) strata from a littoral Argentinean Patagonia salt flat. Cytotoxicity, intracellular transit and immune response induced by two subcutaneous (sc) administrations (days 0 and 21) with BSA entrapped in ARC made of TPL either form BM (ARC-BM) and from GC (ARC-GC) at 2% w/w (BSA/lipids), to C3H/HeN mice (25 μg BSA, 1.3 mg of archaeal lipids per mouse) and boosted on day 180 with 25 μg of bare BSA, were determined.     

Cholesterol metabolism in mice models of genetic hypercholesterolemia

Journal of Physiology and Biochemistry - Monogenic familial hypercholesterolemia is characterized by impaired cellular uptake of apolipoprotein B containing lipoproteins. However, its consequences...     

Correlation of alkylating and mutagenic activities of allyl and allylic compounds: Standard alkylation test vs. kinetic investigation

Thirty-nine allylic and non-allylic compounds have been tested in the standard 4-(p-nitrobenzyl)pyridine (NBP) alkylating procedure and the Salmonella typhimurium mutagenicity assay. Fourteen of these were found directly mutagenic (without addition of S-9 mix activating enzyme system). With twelve of these compounds, a good correlation of alkylating and mutagenic potencies was established; the remaining two do not meet the chemical conditions of the NBP procedure on account of HCl elimination with these two compounds. The other 25 substances were inactive in both systems. The quantitative correlation proved to be almost linear in the lower activity ranges (E ～ 2; revertants/μmol ～ 600). The reasons for some deviations from the linear relationship have been analyzed and discussed on the basis of structural features. In addition to the standard alkylation test, a modified NBP-test was performed in order to obtain kinetic data and activation energy values. The results with 6 representative allylic compounds show that the overall correlation is not substantially improved above that of the standard procedure; nonetheless, additional information on reaction characteristics is obtained with some substances.