Supplementation with vitamin E but not with vitamin C lowers lipid peroxidation in vivo in mildly hypercholesterolemic men

Although the use of vitamin E supplements has been associated with a reduction in coronary events, assumed to be due to lowered lipid peroxidation, there are no previous long-term clinical trials into the effects of vitamin C or E supplementation on lipid peroxidation in vivo. Here, we have studied the long-term effects of vitamins C and E on plasma F₂-isoprostanes, a widely used marker of lipid peroxidation in vivo. As a study cohort, a subset of the “Antioxidant Supplementation in Atherosclerosis Prevention” (ASAP) study was used. ASAP is a double-masked placebo-controlled randomized clinical trial to study the long-term effect of vitamin C (500 mg of slow release ascorbate daily), vitamin E (200 mg of d-α-tocopheryl acetate daily), both vitamins (CellaVie^®), or placebo on lipid peroxidation, atherosclerotic progression, blood pressure and myocardial infarction (n = 520 at baseline). Lipid peroxidation measurements were carried out in 100 consecutive men at entry and repeated at 12 months. The plasma F₂-isoprostane concentration was lowered by 17.3% (95% CI 3.9–30.8%) in the vitamin E group (p = 0.006 for the change, as compared with the placebo group). On the contrary, vitamin C had no significant effect on plasma F₂-isoprostanes as compared with the placebo group. There was also no interaction in the effect between these vitamins. In conclusion, long-term oral supplementation of clinically healthy, but hypercholesterolemic men, who have normal vitamin C and E levels with a reasonable dose of vitamin E lowers lipid peroxidation in vivo, but a relatively high dose of vitamin C does not. This observation may provide a mechanism for the observed ability of vitamin E supplements to prevent atherosclerosis.     

Effects of honey bee (Apis mellifera L.) queen insemination volume on worker behavior and physiology

Honey bee colonies consist of tens of thousands of workers and a single reproductive queen that produces a pheromone blend which maintains colony organization. Previous studies indicated that the insemination quantity and volume alter queen mandibular pheromone profiles. In our 11-month long field study we show that workers are more attracted to high-volume versus low-volume inseminated queens, however, there were no significant differences between treatments in the number of queen cells built by workers in preparation for supersedure. Workers exposed to low-volume inseminated queens initiated production of queen-like esters in their Dufour's glands, but there were no significant difference in the amount of methyl farnesoate and juvenile hormone in worker hemolymph. Lastly, queen overwintering survival was unexpectedly lower in high-volume inseminated queens. Our results suggest that the queen insemination volume could ultimately affect colony health and productivity.     

Isolation and characterization of phage–host systems from the Baltic Sea ice

In search for sea ice bacteria and their phages from the Baltic Sea ice, two ice samples were collected from land-fast ice in a south-west Finland coastal site in February and March 2011. Bacteria were isolated from the melted sea ice samples and phages were screened from the same samples for 43 purified isolates. Plaque-producing phages were found for 15 bacterial isolates at 3 °C. Ten phage isolates were successfully plaque purified and eight of them were chosen for particle purification to analyze their morphology and structural proteins. Phage 1/32 infecting an isolate affiliated to phylum Bacteroidetes (Flavobacterium sp.) is a siphovirus and six phages infecting isolates affiliated to γ-Proteobacteria (Shewanella sp.) hosts were myoviruses. Cross titrations between the hosts showed that all studied phages are host specific. Phage solutions, host growth and phage infection were tested in different temperatures revealing phage temperature tolerance up to 45 °C, whereas phage infection was in most of the cases retarded above 15 °C. This study is the first to report isolation and cultivation of ice bacteria and cold-active phages from the Baltic Sea ice.     

Persistence length of fascin-cross-linked actin filament bundles in solution and the in vitro motility assay

Background

Bundles of unipolar actin filaments (F-actin), cross-linked via the actin-binding protein fascin, are important in filopodia of motile cells and stereocilia of inner ear sensory cells. However, such bundles are also useful as shuttles in myosin-driven nanotechnological applications. Therefore, and for elucidating aspects of biological function, we investigate if the bundle tendency to follow straight paths (quantified by path persistence length) when propelled by myosin motors is directly determined by material properties quantified by persistence length of thermally fluctuating bundles.

Methods

Fluorescent bundles, labeled with rhodamine-phalloidin, were studied at fascin:actin molar ratios: 0:1 (F-actin), 1:7, 1:4 and 1:2. Persistence lengths (Lp) were obtained by fitting the cosine correlation function (CCF) to a single exponential function: < cos(θ(0) − θ(s)) > = exp(−s / (2Lp)) where θ(s) is tangent angle; s: path or contour lengths. < > denotes averaging over filaments.

Results

Bundle-Lp (bundles < 15 μm long) increased from ~ 10 to 150 μm with increased fascin:actin ratio. The increase was similar for path-Lp (path < 15 μm), with highly linear correlation. For longer bundle paths, the CCF-decay deviated from a single exponential, consistent with superimposition of the random path with a circular path as suggested by theoretical analysis.

Conclusions

Fascin–actin bundles have similar path-Lp and bundle-Lp, both increasing with fascin:actin ratio. Path-Lp is determined by the flexural rigidity of the bundle.

General significance

The findings give general insight into mechanics of cytoskeletal polymers that interact with molecular motors, aid rational development of nanotechnological applications and have implications for structure and in vivo functions of fascin–actin bundles.     

Auditory short-term memory behaves like visual short-term memory

Are the information processing steps that support short-term sensory memory common to all the senses? Systematic, psychophysical comparison requires identical experimental paradigms and comparable stimuli, which can be challenging to obtain across modalities. Participants performed a recognition memory task with auditory and visual stimuli that were comparable in complexity and in their neural representations at early stages of cortical processing. The visual stimuli were static and moving Gaussian-windowed, oriented, sinusoidal gratings (Gabor patches); the auditory stimuli were broadband sounds whose frequency content varied sinusoidally over time (moving ripples). Parallel effects on recognition memory were seen for number of items to be remembered, retention interval, and serial position. Further, regardless of modality, predicting an item's recognizability requires taking account of (1) the probe's similarity to the remembered list items (summed similarity), and (2) the similarity between the items in memory (inter-item homogeneity). A model incorporating both these factors gives a good fit to recognition memory data for auditory as well as visual stimuli. In addition, we present the first demonstration of the orthogonality of summed similarity and inter-item homogeneity effects. These data imply that auditory and visual representations undergo very similar transformations while they are encoded and retrieved from memory.     

SHARPIN regulates collagen architecture and ductal outgrowth in the developing mouse mammary gland

SHARPIN is a widely expressed multifunctional protein implicated in cancer, inflammation, linear ubiquitination and integrin activity inhibition; however, its contribution to epithelial homeostasis remains poorly understood. Here, we examined the role of SHARPIN in mammary gland development, a process strongly regulated by epithelial–stromal interactions. Mice lacking SHARPIN expression in all cells (Sharpin^cpdm), and mice with a stromal (S100a4‐Cre) deletion of Sharpin, have reduced mammary ductal outgrowth during puberty. In contrast, Sharpin^cpdm mammary epithelial cells transplanted in vivo into wild‐type stroma, fully repopulate the mammary gland fat pad, undergo unperturbed ductal outgrowth and terminal differentiation. Thus, SHARPIN is required in mammary gland stroma during development. Accordingly, stroma adjacent to invading mammary ducts of Sharpin^cpdm mice displayed reduced collagen arrangement and extracellular matrix (ECM) stiffness. Moreover, Sharpin^cpdm mammary gland stromal fibroblasts demonstrated defects in collagen fibre assembly, collagen contraction and degradation in vitro. Together, these data imply that SHARPIN regulates the normal invasive mammary gland branching morphogenesis in an epithelial cell extrinsic manner by controlling the organisation of the stromal ECM.     

Terrestrial isopods (Crustacea: Isopoda: Oniscidea) from Brazilian caves

To date, six species of terrestrial isopods were known from Brazilian caves, but only four could be classified as troglobites. This article deals with material of Oniscidea collected in many Brazilian karst caves in the states of Pará, Bahia, Minas Gerais, Mato Grosso do Sul, and São Paulo, and deposited in the collections of the Museu de Zoologia, Universidade de São Paulo, the Coleção de Carcinologia do Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, and the collection of the Natural History Museum, Section of Zoology ‘La Specola’, Florence. Three new genera have been recognized: Spelunconiscus gen. nov. and Xangoniscus gen. nov. (Styloniscidae), and Leonardoscia gen. nov. (Philosciidae). Twenty‐two species have been identified, 11 of which in the families Styloniscidae, Philosciidae, Scleropactidae, Plathyartridae, Dubioniscidae, and Armadillidae are new to science: Leonardoscia hassalli sp. nov., Metaprosekia quadriocellata sp. nov. , Metaprosekia caupe sp. nov. , Amazoniscus leistikowi sp. nov. , Novamundoniscus altamiraensis sp. nov. , Trichorhina yiara sp. nov. , Trichorhina curupira sp. nov. , and Ctenorillo ferrarai sp. nov. from Pará; Xangoniscus aganju sp. nov. from Bahia; and Spelunconiscus castroi sp. nov. and Trichorhina anhanguera sp. nov. from Minas Gerais. Four new species in the families Styloniscidae ( Spelunconiscus castroi sp. nov. and Xangoniscus aganju sp. nov. ), Philosciidae ( Leonardoscia hassalli sp. nov. ), and Scleropactidae ( Amazoniscus leistikowi sp. nov. ) with highly troglomorphic traits can be considered as troglobitic, whereas all the remaining species are either troglophilic or accidentals. Brazilian caves are now under potential threat because of recent legislation, and the knowledge of the subterranean biodiversity of the country is thus of primary importance. © 2014 The Linnean Society of London     

Stem wood properties of Populus tremuloides, Betula papyrifera and Acer saccharum saplings after 3 years of treatments to elevated carbon dioxide and ozone

The aim of this study was to examine the effects of elevated carbon dioxide [CO₂] and ozone [O₃] and their interaction on wood chemistry and anatomy of five clones of 3‐year‐old trembling aspen (Populus tremuloides Michx.). Wood chemistry was studied also on paper birch (Betula papyrifera Marsh.) and sugar maple (Acer saccharum Marsh.) seedling‐origin saplings of the same age. Material for the study was collected from the Aspen Free‐Air CO₂ Enrichment (FACE) experiment in Rhinelander, WI, USA, where the saplings had been exposed to four treatments: control (C; ambient CO₂, ambient O₃), elevated CO₂ (560 ppm during daylight hours), elevated O₃ (1.5 × ambient during daylight hours) and their combination (CO₂+O₃) for three growing seasons (1998–2000). Wood chemistry responses to the elevated CO₂ and O₃ treatments differed between species. Aspen was most responsive, while maple was the least responsive of the three tree species. Aspen genotype affected the responses of wood chemistry and, to some extent, wood structure to the treatments. The lignin concentration increased under elevated O₃ in four clones of aspen and in birch. However, elevated CO₂ ameliorated the effect. In two aspen clones, nitrogen in wood samples decreased under combined exposure to CO₂ and O₃. Soluble sugar concentration in one aspen clone and starch concentration in two clones were increased by elevated CO₂. In aspen wood, α‐cellulose concentration changed under elevated CO₂, decreasing under ambient O₃ and slightly increasing under elevated O₃. Hemicellulose concentration in birch was decreased by elevated CO₂ and increased by elevated O₃. In aspen, elevated O₃ induced statistically significant reductions in distance from the pith to the bark and vessel lumen diameter, as well as increased wall thickness and wall percentage, and in one clone, decreased fibre lumen diameter. Our results show that juvenile wood properties of broadleaves, depending on species and genotype, were altered by atmospheric gas concentrations predicted for the year 2050 and that CO₂ ameliorates some adverse effects of elevated O₃ on wood chemistry.     

Disrupted Sperm Function and Fertilin β Processing in Mice Deficient in the Inositol Polyphosphate 5-Phosphatase Inpp5b

Inpp5b is an ubiquitously expressed type II inositol polyphosphate 5-phosphatase. We have disrupted the Inpp5b gene in mice and found that homozygous mutant males are infertile. Here we examine the causes for the infertility in detail. We demonstrate that sperm from Inpp5b^−/− males have reduced motility and reduced ability to fertilize eggs, although capacitation and acrosome exocytosis appear to be normal. In addition, fertilin β, a sperm surface protein involved in sperm-egg membrane interactions that is normally proteolytically processed during sperm transit through the epididymis, showed reduced levels of processing in the Inpp5b^−/− animals. Inpp5b was expressed in the Sertoli cells and epididymis and at low levels in the developing germ cells; however, mice lacking Inpp5b in spermatids and not in other cell types generated by conditional gene targeting, were fully fertile. The abnormalities in mutant sperm function and maturation appear to arise from defects in the functioning of Sertoli and epididymal epithelial cells. Our results directly demonstrate a previously unknown role for phosphoinositides in normal sperm maturation beyond their previously characterized involvement in the acrosome reaction. Inpp5b^−/− mice provide an excellent model to study the role of Sertoli and epididymal epithelial cells in the differentiation and maturation of sperm.