Alpha/beta interferons fail to induce antiviral activity from within the nucleus.

Electrophoretically pure murine alpha/beta interferons (IFN-alpha/beta) were microinjected directly into the nuclei of mouse L cells, each nucleus receiving 10 fl containing about 20,000 (IFN) molecules, an amount sufficient to induce the antiviral state when added to the culture medium of control cells. Three, six or 24 h after intranuclear delivery, the cells were challenged with vesicular stomatitis virus or Semliki Forest virus and the appearance of cytopathic effects was scored for each individual cell. The scoring of more than 1,000 intranuclearly injected cells in nine different experiments showed unambiguously that the intranuclear delivery of IFN-alpha/beta did not induce the antiviral state. The results argue strongly against the physiological importance of high-affinity nuclear binding sites for native IFN that have been recently described (V. M. Kushnaryov, H. S. MacDonald, G. P. Lemense, J. Debruin, J. J. Sedmak, and S. E. Grossberg, Cytobios 53:185-197, 1988). Together with earlier results of other groups describing the lack of IFN activity after intracytoplasmic injection (Y. Higashi and Y. Sokawa, J. Biochem. 91:2021-2028, 1982; G. Huez, M. Silhol, and B. Lebleu, Biochem. Biophys. Res. Commun. 110:155-160, 1983), these results lend weight to the hypothesis that the binding of IFN-alpha/beta to the plasma membrane receptor is sufficient to set into motion the complex mechanism of transmembrane signalling without requiring internalization of the bound IFN molecules.     

Habitat deterioration promotes the evolution of direct development in metamorphosing species

Although metamorphosis is widespread in the animal kingdom, several species have evolved life-cycle modifications to avoid complete metamorphosis. Some species, for example, many salamanders and newts, have deleted the adult stage via a process called paedomorphosis. Others, for example, some frog species and marine invertebrates, no longer have a distinct larval stage and reach maturation via direct development. Here we study which ecological conditions can lead to the loss of metamorphosis via the evolution of direct development. To do so, we use size-structured consumer-resource models in conjunction with the adaptive-dynamics approach. In case the larval habitat deteriorates, individuals will produce larger offspring and in concert accelerate metamorphosis. Although this leads to the evolutionary transition from metamorphosis to direct development when the adult habitat is highly favorable, the population will go extinct in case the adult habitat does not provide sufficient food to escape metamorphosis. With a phylogenetic approach we furthermore show that among amphibians the transition of metamorphosis to direct development is indeed, in line with model predictions, conditional on and preceded by the evolution of larger egg sizes.     

Effect of stocking density on the behavior of newly transformed juvenile Macrobrachium rosenbergii

This study characterized the behavioral activity of Macrobrachium rosenbergii in the early stages of development, under different stocking densities (25 and 40 animals/m²), and during the light and dark phases of a 24-h cycle. Observations of individuals were made in 8 aquariums. Behavioral recording lasted 15 min/aquarium, 4 times/day and 4 days/week, 4 weeks in total. Food was offered twice daily. Observational methods included a combination of behavioral sampling and scan sampling. During the light phase, inactivity, cleaning and remaining in a shelter were the most frequent behaviors. During the dark phase the subjects displayed a higher frequency of feeding, exploration, swimming, and digging. At low density, the animals gained more weight and exhibited greater growth overall. These results indicate a behavioral pattern that is more favorable to animals in the lower density cultivation environment that can also create better living conditions for these shrimp, favor survival rates and therefore improve management success.     

Analysis of synaptonemal complexes in a heterozygous human male carrier of a reciprocal translocation involving an acrocentric chromosome: heterosynapsis without previous homosynapsis

Summary Silver-stained synaptonemal complexes in surface-spread pachytene nuclei from an oligospermic man, heterozygous for a reciprocal translocation involving an acrocentric chromosome, were analyzed by electron microscopy. Contrary to the classically expected configuration, nonhomologous pairing was observed with asymetrical association of the lateral elements of the nonhomologous arms of the quadrivalents. A possible role of heterosynapsis in germ cell conservation is discussed.     

When the same is not the same: phenotypic variation reveals different plant ecological strategies within species occurring in distinct Neotropical savanna habitats

Variations in abiotic characteristics such as soil water availability and fertility impose different selective pressures on plant populations. This may produce intraspecific variability in functional traits, even at a fine spatial scale. We investigated whether functional traits related to water-use efficiency, resource-retention strategy, soil nutrient acquisition, and fire tolerance differ in species that occur in two different habitats of Brazilian Cerrado: rocky savannas and savanna woodlands. Rocky savannas occur over sandstone, quartzite outcrops and have shallow nutrient-poor and low-moisture rocky soils, while savanna woodlands occur over well-drained and deep soils with frequent fire regimes. We measured nine functional traits of 40 tree species that occur in both habitats. Rocky savanna individuals exhibited a greater water-use efficiency strategy. The resource-retention strategy in rocky savanna individuals was corroborated by lower adult maximum height. However, despite the lower nutrient availability in rocky savanna soils, we only detected lower leaf phosphorus content in individuals from this habitat. Furthermore, individuals from both habitats had equally thick bark, suggesting that the fire-defense strategy is related to a stable, rather than plastic trait. Overall, our results highlight the central role of contrasting soil water availability patterns in driving phenotypic plasticity within species. We conclude that savanna species are responding to water and nutrient availabilities, via plasticity in traits related to the resource-retention strategy, and preparing for future fires, via uniformly thick bark. Wide plant distribution in contrasting habitats is possible for species that can shift ecological strategies to survive in nutrient- and water-limited habitats such as rocky savannas.     

Potential Conflicts of Interest of Editorial Board Members from Five Leading Spine Journals

Conflicts of interest arising from ties between pharmaceutical industry and physicians are common and may bias research. The extent to which these ties exist among editorial board members of medical journals is not known. This study aims to determine the prevalence and financial magnitude of potential conflicts of interest among editorial board members of five leading spine journals. The editorial boards of: The Spine Journal; Spine; European Spine Journal; Journal of Neurosurgery: Spine; and Journal of Spinal Disorders & Techniques were extracted on January 2013 from the journals’ websites. Disclosure statements were retrieved from the 2013 disclosure index of the North American Spine Society; the program of the 20th International Meeting on Advanced Spine Techniques; the program of the 48th Annual Meeting of the Scoliosis Research Society; the program of the AOSpine global spine congress; the presentations of the 2013 Annual Eurospine meeting; and the disclosure index of the American Academy of Orthopaedic Surgeons. Names of the editorial board members were compared with the individuals who completed a disclosure for one of these indexes. Disclosures were extracted when full names matched. Two hundred and ten (29%) of the 716 identified editorial board members reported a potential conflict of interest and 154 (22%) reported nothing to disclose. The remaining 352 (49%) editorial board members had no disclosure statement listed for one of the indexes. Eighty-nine (42%) of the 210 editorial board members with a potential conflict of interest reported a financial relationship of more than $10,000 during the prior year. This finding confirms that potential conflicts of interest exist in editorial boards which might influence the peer review process and can result in bias. Academia and medical journals in particular should be aware of this and strive to improve transparency of the review process. We emphasize recommendations that contribute to achieving this goal.     

Plasma Biomarkers Discriminate Clinical Forms of Multiple Sclerosis

Multiple sclerosis, the most common cause of neurological disability in young population after trauma, represents a significant public health burden. Current challenges associated with management of multiple sclerosis (MS) patients stem from the lack of biomarkers that might enable stratification of the different clinical forms of MS and thus prompt treatment for those patients with progressive MS, for whom there is currently no therapy available. In the present work we analyzed a set of thirty different plasma cytokines, chemokines and growth factors present in circulation of 129 MS patients with different clinical forms (relapsing remitting, secondary progressive and primary progressive MS) and 53 healthy controls, across two independent cohorts. The set of plasma analytes was quantified with Luminex xMAP technology and their predictive power regarding clinical outcome was evaluated both individually using ROC curves and in combination using logistic regression analysis. Our results from two independent cohorts of MS patients demonstrate that the divergent clinical and histology-based MS forms are associated with distinct profiles of circulating plasma protein biomarkers, with distinct signatures being composed of chemokines and growth/angiogenic factors. With this work, we propose that an evaluation of a set of 4 circulating biomarkers (HGF, Eotaxin/CCL11, EGF and MIP-1β/CCL4) in MS patients might serve as an effective tool in the diagnosis and more personalized therapeutic targeting of MS patients.