The effect of multiple paternity on genetic diversity during and after colonisation

In metapopulations, genetic variation of local populations is influenced by the genetic content of the founders, and of migrants following establishment. We analyse the effect of multiple paternity on genetic diversity using a model in which the highly promiscuous marine snail Littorina saxatilis expands from a mainland to colonise initially empty islands of an archipelago. Migrant females carry a large number of eggs fertilised by 1 - 10 mates. We quantify the genetic diversity of the population in terms of its heterozygosity: initially during the transient colonisation process, and at long times when the population has reached an equilibrium state with migration. During colonisation, multiple paternity increases the heterozygosity by 10 - 300 % in comparison with the case of single paternity. The equilibrium state, by contrast, is less strongly affected: multiple paternity gives rise to 10 - 50 % higher heterozygosity compared with single paternity. Further we find that far from the mainland, new mutations spreading from the mainland cause bursts of high genetic diversity separated by long periods of low diversity. This effect is boosted by multiple paternity. We conclude that multiple paternity facilitates colonisation and maintenance of small populations, whether or not this is the main cause for the evolution of extreme promiscuity in Littorina saxatilis.Comment: 7 pages, 5 figures, electronic supplementary materia

Нанохайку и нанохайга, или как нанотехнологиите се срещат с изкуството

The present work combines science and arts in an innovative and intriguing way. Using Electron Beam Lithography (EBL) and Directed Self-Assembly (DSA) of Block Co-Polymers (BCP) in conjunction with the shortest poetic form, haiku, the paper attractively demonstrate the capabilities of these nanofabrication techniques and explores the interaction between the top-down EBL process and the bottom-up DSA approach. Silicon (Si) substrates and EBL with the hydrogen silsesquioxane (HSQ) negative tone resist were used for capturing examples of the tiniest haiku poems written and translated into six languages having four different character styles. Subsequently, the haiku nanostructures (“nanohaiku”) were used as guiding features between which the poly(styrene)-blockpoly(ethylene oxide) (PS-b-PEO) diblock copolymer is spin coated to create self-organised nanopatterns. The annealing was done in toluene solvent vapours at 50°C for 1.5 hours and then the samples were immersed in ethanol for 15 hours at 40°C to dissolve the PEO copolymer. In areas within and in-between the individual characters and syllables of the poems, unusual patterns were observed. We interpret them as self-assembled “nanohaiga” directed by the morphology and the linguistic geometry of the nanohaiku. Moreover, we demonstrate how the BCP pattern changes when interacting with the same verse translated into different languages. Thus we add to the haiku poem's own nanostructure and meaning a new visual identity, nanohaiga, combining for the first time poetry, visual art and advanced nanofabrication technologies

Optimization of Hypoxic Brain Injuries Diagnostics in Full-Term Newborns

The problem of early diagnosis of the central nervous system damage in newborn before the onset of clinical symptoms remains relevant at the present time.The aim of the study was to optimize the hypoxic brain damage diagnosis in full-term newborns by analyzing the concentration of cytokines in the umbilical cord blood.Materials and methods. During the first stage of the study, a prospective analysis of concentrations of interleukins (IL-1β, IL-4, IL-6, IL-8, IL-10), TNF-α and neuron-specific enolase (NSE) in the umbilical cord blood serum of full-term newborns was performed. The second stage of the study included the retrospective analysis of clinical data and instrumental research methods. The main method for diagnosing in the development of hypoxic brain damage in newborns was neurosonography.Results. The development of hypoxic brain damage is evidenced by the concentration of IL-1β over 30.3 pg/ml, IL-4 – over 1.7 pg/ml, IL-6 – over 79.4 pg/ml, IL-8 – over 107.7 pg/ml, NSE – more than 10.3 ng/ml and TNF-α – more than 1.6 pg/ml in umbilical cord blood.Conclusion. The results of the study confirmed that the comprehensive assessment of the cytokines concentration in the umbilical cord blood improves the hypoxic brain damage diagnosis in newborns. Analysis of the level of these markers immediately after the birth will optimize the management tactics of newborns who have undergone hypoxic exposure in antenatal and intranatal period

Transcriptomic resources for evolutionary studies in flat periwinkles and related species

The flat periwinkles, Littorina fabalis and L. obtusata, comprise two sister gastropod species that have an enormous potential to elucidate the mechanisms involved in ecological speciation in the marine realm. However, the molecular resources currently available for these species are still scarce. In order to circumvent this limitation, we used RNA-seq data to characterize the transcriptome of four individuals from each species sampled in different locations across the Iberian Peninsula. Four de novo transcriptome assemblies were generated, as well as a pseudo-reference using the L. saxatilis reference transcriptome as backbone. After transcripts’ annotation, variant calling resulted in the identification of 19,072 to 45,340 putatively species-diagnostic SNPs. The discriminatory power of a subset of these SNPs was validated by implementing an independent genotyping assay to characterize reference populations, resulting in an accurate classification of individuals into each species and in the identification of hybrids between the two. These data comprise valuable genomic resources for a wide range of evolutionary and conservation studies in flat periwinkles and related taxa

Selective Inhibition of p300 HAT Blocks Cell Cycle Progression, Induces Cellular Senescence, and Inhibits the DNA Damage Response in Melanoma Cells

Epigenetic events, including covalent post-translational modifications of histones, have been demonstrated to have critical roles in tumor development and progression. The transcriptional coactivator p300/CBP possesses both histone acetyltransferase (HAT) activity and scaffolding properties that directly influence the transcriptional activation of targeted genes. We have used a potent and specific inhibitor of p300/CBP HAT activity, C646, in order to evaluate the functional contributions of p300/CBP HAT to tumor development and progression. Here we report that C646 inhibits the growth of human melanoma and other tumor cells and promotes cellular senescence. Global assessment of the p300 HAT transcriptome in human melanoma identified functional roles in promoting cell cycle progression, chromatin assembly, and activation of DNA repair pathways through direct transcriptional regulatory mechanisms. In addition, C646 is shown to promote sensitivity to DNA damaging agents, leading to the enhanced apoptosis of melanoma cells after combination treatment with cisplatin. Together, our data suggest that p300 HAT activity mediates critical growth regulatory pathways in tumor cells and may serve as a potential therapeutic target for melanoma and other malignancies by promoting cellular responses to DNA damaging agents that are currently ineffective against specific cancers

Социо-эколого-экономическая политика внедрения химико-технологических инноваций

Article shows necessity of state regulation in sphere of industrial production for the purpose of maintenance of a socio-ecologo-economic orientation of an investment policy on introduction of himiko-technological innovations. Article is written in respect of preparation for the international conference devoted to a sustainable development of «Rio+20».Рассматривается необходимость усиления роли государства в сфере промышленного про-изводства с целью обеспечения социо-эколого-экономической направленности инвестиционной политики по внедрению химико-технологических инноваций. Статья написана в плане подготовки к международной конференции «Рио+20», посвященной устойчивому развитию

Hypocrates is a genetically encoded fluorescent biosensor for (pseudo)hypohalous acids and their derivatives

The lack of tools to monitor the dynamics of (pseudo)hypohalous acids in live cells and tissues hinders a better understanding of inflammatory processes. Here we present a fluorescent genetically encoded biosensor, Hypocrates, for the visualization of (pseudo)hypohalous acids and their derivatives. Hypocrates consists of a circularly permuted yellow fluorescent protein integrated into the structure of the transcription repressor NemR from Escherichia coli. We show that Hypocrates is ratiometric, reversible, and responds to its analytes in the 106 M-1s-1 range. Solving the Hypocrates X-ray structure provided insights into its sensing mechanism, allowing determination of the spatial organization in this circularly permuted fluorescent protein-based redox probe. We exemplify its applicability by imaging hypohalous stress in bacteria phagocytosed by primary neutrophils. Finally, we demonstrate that Hypocrates can be utilized in combination with HyPerRed for the simultaneous visualization of (pseudo)hypohalous acids and hydrogen peroxide dynamics in a zebrafish tail fin injury model

Transition metal dichalcogenide nanospheres for high-refractive-index nanophotonics and biomedical theranostics

Recent developments in the area of resonant dielectric nanostructures have created attractive opportunities for concentrating and manipulating light at the nanoscale and the establishment of the new exciting field of all-dielectric nanophotonics. Transition metal dichalcogenides (TMDCs) with nanopatterned surfaces are especially promising for these tasks. Still, the fabrication of these structures requires sophisticated lithographic processes, drastically complicating application prospects. To bridge this gap and broaden the application scope of TMDC nanomaterials, we report here femtosecond laser-ablative fabrication of water-dispersed spherical TMDC (MoS2 and WS2) nanoparticles (NPs) of variable size (5 to 250 nm). Such NPs demonstrate exciting optical and electronic properties inherited from TMDC crystals, due to preserved crystalline structure, which offers a unique combination of pronounced excitonic response and high refractive index value, making possible a strong concentration of electromagnetic field in the NPs. Furthermore, such NPs offer additional tunability due to hybridization between the Mie and excitonic resonances. Such properties bring to life a number of nontrivial effects, including enhanced photoabsorption and photothermal conversion. As an illustration, we demonstrate that the NPs exhibit a very strong photothermal response, much exceeding that of conventional dielectric nanoresonators based on Si. Being in a mobile colloidal state and exhibiting superior optical properties compared to other dielectric resonant structures, the synthesized TMDC NPs offer opportunities for the development of next-generation nanophotonic and nanotheranostic platforms, including photothermal therapy and multimodal bioimaging