No Major Host Genetic Risk Factor Contributed to A(H1N1)2009 Influenza Severity

While most patients affected by the influenza A(H1N1) pandemic experienced mild symptoms, a small fraction required hospitalization, often without concomitant factors that could explain such a severe course. We hypothesize that host genetic factors could contribute to aggravate the disease. To test this hypothesis, we compared the allele frequencies of 547,296 genome-wide single nucleotide polymorphisms (SNPs) between 49 severe and 107 mild confirmed influenza A cases, as well as against a general population sample of 549 individuals. When comparing severe vs. mild influenza A cases, only one SNP was close to the conventional p = 5×10⁻⁸. This SNP, rs28454025, sits in an intron of the GSK233 gene, which is involved in a neural development, but seems not to have any connections with immunological or inflammatory functions. Indirectly, a previous association reported with CD55 was replicated. Although sample sizes are low, we show that the statistical power in our design was sufficient to detect highly-penetrant, quasi-Mendelian genetic factors. Hence, and assuming that rs28454025 is likely to be a false positive, no major genetic factor was detected that could explain poor influenza A course.     

Arthropod fauna on grassland–heathland associations under different grazing managements with domestic ruminants

The effects of two grazer species (cattle or sheep) and two flock types (single or mixed with goats) on vegetation and arthropod fauna were studied in a factorial design on eight plots which comprised two thirds of mechanically cleared heathland and one third of improved ryegrass-clover grassland. After six grazing seasons, the shrubland areas were dominated by gorse (Ulex gallii) in all treatments. Herbaceous cover was higher under mixed than under single grazing, and under sheep than under cattle grazing. Higher captures of Opiliones, Julida, Lithobiomorpha, Microcoryphia and Carabidae were recorded in shrublands than in grasslands, while the reverse was observed for Linyphiidae, Lycosidae and Hemiptera. Within shrublands, fauna responded to the flock type but not to the grazer species. More arthropod groups favoured the patchier areas with higher herbaceous biomass generated by mixed herds with goats. Within grasslands, species-specific responses to the grazer species were observed. Mixed grazing schemes which include goats within partially improved heathlands could contribute to maintain higher biodiversity levels in these marginal areas.     

The Atomic Structure of the HIV-1 gp41 Transmembrane Domain and Its Connection to the Immunogenic Membrane-proximal External Region

The membrane-proximal external region (MPER) C-terminal segment and the transmembrane domain (TMD) of gp41 are involved in HIV-1 envelope glycoprotein-mediated fusion and modulation of immune responses during viral infection. However, the atomic structure of this functional region remains unsolved. Here, based on the high resolution NMR data obtained for peptides spanning the C-terminal segment of MPER and the TMD, we report two main findings: (i) the conformational variability of the TMD helix at a membrane-buried position; and (ii) the existence of an uninterrupted α-helix spanning MPER and the N-terminal region of the TMD. Thus, our structural data provide evidence for the bipartite organization of TMD predicted by previous molecular dynamics simulations and functional studies, but they do not support the breaking of the helix at Lys-683, as was suggested by some models to mark the initiation of the TMD anchor. Antibody binding energetics examined with isothermal titration calorimetry and humoral responses elicited in rabbits by peptide-based vaccines further support the relevance of a continuous MPER-TMD helix for immune recognition. We conclude that the transmembrane anchor of HIV-1 envelope is composed of two distinct subdomains: 1) an immunogenic helix at the N terminus also involved in promoting membrane fusion; and 2) an immunosuppressive helix at the C terminus, which might also contribute to the late stages of the fusion process. The unprecedented high resolution structural data reported here may guide future vaccine and inhibitor developments.     

Analysis of mercury levels in historical bone material from syphilitic subjects--pilot studies (short report)

The aim of the present work is to study the remains of seven individuals with typical symptoms of tertiary syphilis in terms of mercury content in bones, thereby verifying whether they were subjected to treatment and, if they were, how long their organisms were exposed to toxic mercury fumes. Mercury was used, mainly in the Middle Ages and in the early modern period, as a preventive measure in case of individuals suffering from syphilis, a venereal disease, and also leprosy. Syphilitic patients treated this way should demonstrate increased concentration of mercury in their bones. The skeletons studied in the present work originate from various archaeological sites in southern and north-central Poland. The analyses concerned individuals with diagnosed syphilis as well as healthy individuals who constituted the control group. The analyses were performed by the LA-ICP-MS technique, with the use of laser Nd: YAG, Macro, 266 nm, New Wave, USA, coupled with Spectrometer Elan DRC-e Perkin Elmer, USA. The content analysis of the studied bone material revealed with high probability that the contact method of mercurial treatment was used only in the case of two women from north-central Poland, deceased at the turn of the 15th century at the earliest.     

Foliar application of urea to “Sauvignon Blanc” and “Merlot” vines: doses and time of application

A careful control of the N nutritional status of grapevines can have a determining effect on wine characteristics; therefore a suitable management of N fertilization might allow some wine parameters to be modified, thereby improving product quality. The aim of this study was to determine the effect of foliar application of urea at different doses and different times of the growing season on the parameters of Sauvignon Blanc and Merlot grape juice. The research described herein involved Sauvignon Blanc and Merlot grapevines (V. vinifera L.) at a commercial vineyard and was conducted over 2 years. In the first year, N treatment involved a foliar application at a dose of 10 kg N ha^?1 during veraison, whereas in the second year it involved a foliar urea application at two doses (10 and 50 kg N ha^?1) and at three different times—3 weeks before veraison, during veraison and 3 weeks after veraison. In this second year, the urea applied at a dose of 10 kg N ha^?1 was isotopically labelled with 1% ¹⁵N. Chemical parameters, yeast assimilable N, amino acid content, amino acid profile and N isotopic composition were determined for all treatments. Grape and grape-juice parameters for Merlot were found to be more affected by N fertilization than for Sauvignon Blanc and were also more affected during the second year than during the first year, thus indicating that the climatic characteristics of each campaign could affect these parameters. The yeast assimilable N in grape juice was found to be higher for late applications of foliar urea, with application of the higher dose of urea during veraison increasing the amino acid and proline contents in both varieties. The isotopic analysis data showed that the urea applied to leaves was transferred to the berries, with the maximum translocation in Sauvignon Blanc occurring for the post-veraison treatment and in Merlot for the veraison treatment. We can therefore conclude that foliar application of urea could modify grape juice quality and could therefore be used as a tool for obtaining quality wines.     

The problem of the emergence of functional diversity in prebiotic evolution

Since Darwin it is widely accepted that natural selection (NS) is the most important mechanism to explain how biological organisms—in their amazing variety—evolve and, therefore, also how the complexity of certain natural systems can increase over time, creating ever new functions or functional structures/relationships. Nevertheless, the way in which NS is conceived within Darwinian Theory already requires an open, wide enough, functional domain where selective forces may act. And, as the present paper will try to show, this becomes even more evident if one looks into the problem of origins. If there was a time when NS was not operating (as it is quite reasonable to assume), where did that initial functional diversity, necessary to trigger off the process, come from? Self-organization processes may be part of the answer, as many authors have claimed in recent years, but surely not the complete one. We will argue here that a special type of self-maintaining organization, arising from the interplay among a set of different endogenously produced constraints (pre-enzymatic catalysts and primitive compartments included), is required for the appearance of functional diversity in the first place. Starting from that point, NS can progressively lead to new (and, at times, also more complex) organizations that, in turn, provide wider functional variety to be selected for, enlarging in this way the range of action and consequences of the mechanism of NS, in a kind of mutually enhancing effect.