Surface properties of Enterococcus faecalis cells isolated from chicken hearts determine their low ability to form biofilms

Enterococcus faecalis is one of the most significant bacterial pathogens associated with the first-week mortality of chickens. Here, the surface properties of bacterial cells and the selected virulence factors of E. faecalis strains isolated from the hearts of clinically healthy broiler chickens were studied. Investigations were carried out on live and autoclaved cells. E. faecalis (ATCC 29212) was used as a reference strain. The bacterial cells revealed different haemolytic activities. Their surface free energy was dominated by the hydrophobic component. The cell walls of the bird isolates showed slightly weaker acidic characteristics than those of E. faecalis (ATCC 29212). Moreover, the bacterial cells from the chicken hearts showed higher electrophoretic mobility and surface electrical charge than the reference strain, and consequently demonstrated a low ability to form biofilms.     

Restoration of hydro-ecological conditions in Carpathian forested mountain fens

The research was designed to assess benefits of passive restoration, consisting of blocking from drainage ditches and in effect raise the groundwater level, its influence on properties of soil, water, species of plants and mesofauna in the fen Caltho-Alnetum community. The research was carried out in Outer Flysh Carpathians, the area of the Babiogórski National Park (Poland) in 2011–2014. It was established that the degraded communities showed positive reaction to an attempt to restore the original groundwater level. The increase in the groundwater level changed chemical properties of soil and water of the community such as: pH, sorption properties and the ionic composition of groundwater. Changes in habitat conditions resulted in different species composition of soil mesofauna and plants growing in the restorative community.     

Cytotoxic,tubulin-interfering and proapoptotic activities of 4′-methylthio-<Emphasis Type="Italic">trans</Emphasis>-stilbene derivatives,analogues of <Emphasis Type="Italic">trans</Emphasis>-resveratrol

The aim of this study was to evaluate the cytotoxicity of a series of seven 4′-methylthio-trans-stilbene derivatives against cancer cells: MCF7 and A431 in comparison with non-tumorigenic MCF12A and HaCaT cells. The mechanism of anti-proliferative activity of the most cytotoxic trans-resveratrol analogs: 3,4,5-trimethoxy-4′-methylthio-trans-stilbene (3,4,5-MTS) and 2,4,5-trimethoxy-4′-methylthio-trans-stilbene (2,4,5-MTS) was analyzed and compared with the effect of trans-resveratrol. All the compounds that were studied exerted a stronger cytotoxic effect than trans-resveratrol did. MCF7 cells were the most sensitive to the cytotoxic effect of trans-resveratrol analogs with IC₅₀ in the range of 2.1–6.0 µM. Comparing the cytotoxicity of 3,4,5-MTS and 2,4,5-MTS, a significantly higher cytotoxic activity of these compounds against MCF7 versus MCF12A was observed, whereas no significant difference was observed in cytotoxicity against A431 and HaCaT. In the series of 4′-methylthio-trans-stilbenes, 3,4,5-MTS and 2,4,5-MTS were the most promising compounds for further mechanistic studies. The proapoptotic activity of 3,4,5-MTS and 2,4,5-MTS, estimated with the use of annexin-V/propidium iodide assay, was comparable to that of trans-resveratrol. An analysis of cell cycle distribution showed a significant increase in the percentage of apoptotic cells and G2/M phase arrest in MCF7 and A431 as a result of treatment with 3,4,5-MTS, whereas trans-resveratrol tended to increase the percentage of cells in S phase, particularly in epithelial breast cells MCF12A and MCF7. Both trans-stilbene derivatives enhanced potently tubulin polymerization in a dose-dependent manner with sulfur atom participating in the interactions with critical residues of the paclitaxel binding site of β-tubulin.     

Variation in melanin pigmentation of a sexually selected plumage trait and its adaptive value in the Common Snipe Gallinago gallinago

There is increasing evidence that melanin‐based plumage coloration correlates with different components of fitness and that it may act as a social or sexual signal of individual quality. We analysed variation in melanin pigmentation in the outermost tail feathers of the Common Snipe Gallinago gallinago. During courtship flights, male Snipe use their outermost tail feathers to generate a drumming sound, which plays a role in territory establishment and mate choice. As the outermost tail feathers are displayed to females during these flights, we predicted that conspicuous variation in their rusty‐brown (pheomelanin‐based) coloration may act as an honest signal of individual quality. To test this prediction, we spectrophotometrically measured brightness (an indicator of total melanin content) and red chroma (an indicator of pheomelanin content) of the outermost tail feathers in 180 juvenile and adult Common Snipe. An age‐related decline in feather brightness was found exclusively in females, suggesting that melanization could have evolved by natural selection to camouflage incubating birds. In both sexes, brightness of the tail feathers was inversely correlated with their structural quality (as measured with mass–length residuals), suggesting that melanization could increase mechanical properties of feathers and, in males, enhance the quality of courtship sonation. Red chroma positively correlated with total plasma protein concentration, supporting our prediction that pheomelanin pigmentation of tail feathers may act as an honest signal of condition. Our study indicated that variation in the melanin‐based coloration of the outermost tail feathers in the Common Snipe could have evolved as a result of several different selection pressures and it emphasizes the complexity of the processes that underlie the evolution of melanin‐based plumage coloration in birds.     

Lower Jurassic Bahamian-type facies in the Choč Nappe (Tatra Mts,West Carpathians,Poland) influenced by paleocirculation in the Western Tethys

The Lower Jurassic (upper Sinemurian) of the Hronicum domain (Tatra Mts., Western Carpathians, Poland) represents typical tropical shallow-water carbonates of the Bahamian-type. Eight microfacies recognized include oolitic-peloidal grainstone/packstone, peloidal-bioclastic grainstone, peloidal-lithoclastic-bioclastic-cortoidal grainstone/packstone, peloidal-bioclastic packstone/grainstone, peloidal-bioclastic wackestone, spiculitic wackestone, recrystallized peloidal-oolitic grainstone and subordinate dolosparites. The studied sediments were deposited on a shallow-water carbonate platform characterized by normal salinity, in high-energy oolite shoals, bars, back-margin, protected shallow lagoon and subordinately on restricted tidal flat. Some of them contain the microcoprolite Parafavreina, green alga Palaeodasycladus cf. mediterraneous (Pia) and Cayeuxia, typical of the Early Jurassic carbonate platforms of the Western Tethys. The spiculite wackestone from the upper part of the studied succession was deposited in a transitional to deeper-water setting. The studied upper Sinemurian carbonates of the Hronicum domain reveal microfacies similar to the other Bahamian-type platform carbonates of the Mediterranean region. Thereby, they record the northern range of the Lower Jurassic tropical shallow-water carbonates in the western part of the Tethys, albeit the thickness of the Bahamian-type carbonate successions generally decrease in a northerly direction. The sedimentation of the Bahamian-type deposits in the Hronicum domain, located during the Early Jurassic at about 28°N, besides other specific factors (i.e., light, salinity, and nutrients) was strongly controlled by the paleocirculation of warm ocean currents in the Western Tethys.     

Localization of the membrane-associated region of vesicular stomatitis virus M protein at the N terminus, using the hydrophobic, photoreactive probe 125I-TID.

The membrane-reactive, photoactivatable probe 125I-TID [3-(trifluoromethyl)-3-(m-[125I]iodophenyl)-3H-diazirine] was found to label the M protein of vesicular stomatitis virus about 40% as much as G protein in intact virions, in agreement with labeling studies with other probes. By analyzing limited tryptic digestion and specific chemical cleavage products, the label was essentially entirely localized within the first 19, and probably within the first 5 to 10, amino acid residues at the N terminus, identifying this short amphipathic segment as the likely site of interaction of M protein with the viral bilayer.     

Decline ofPotentillo albae-Quercetum phytocoenoses associated with the invasion ofCarpinus betulus

The study area in the Bialowieza primeval forest-size 28000 m², divided into quadrats of 100 m², comprised two patches ofPotentillo albae-Quercetum as distinguished by phytosociological methods, and a fragment of an adjacent very largeTilio-Carpinetum stand. The directional variation in the distribution ofCarpinus betulus trunk diameter values in the southern part of the study area indicates invasion of this oak forest byCarpinus. This process probably started 1962–1968. The invasion ofCarpinus betulus caused considerable deterioration in light conditions of the ground layer, as deduced from a decrease in Ellenberg light index values. The phytosociological division of the study area correlates with variation in the spatial pattern ofCarpinus mean trunk diameter distribution.Quadrat groups were distinguished by association analysis. They were described phytosociologically using systematic group values for species, constituting the characteristic combination for thePotentillo albae-Quercetum. Areas occupied by still olderCarpinus individuals correspond to successive stages of oak forest regression. The deterioration of light conditions caused recession of thermo-and heliophilous oak-forest species and decline ofPotentillo albae-Quercetum phytocoenoses. However, this was not accompanied by the expansion pansion of species ofCarpinus forests.     

Nucleoside imidodiphosphates synthesis and biological activities.

The synthesis of imidodiphosphate analogues of natural nucleoside 5'-diphosphates including adenosine 5'-imidodiphosphate (4a), guanosine 5'-imidodiphosphate (4b), 2'-deoxyadenosine 5'-imidodiphosphate (4c), and 2'-deoxy-guanosine 5'-imidodiphosphate (4d) has been accomplished for the first time. These compounds are the products of the reaction between nucleosides and trichloro [(dichlorophosphoryl)imido] phosphorane in trimethyl phosphate. Some of the major by-products of the reaction including 5'-deoxy-5'-chloro nucleosides are discussed. Compounds 4b, 4c, and 4d are potent inhibitors of ecto-5'-nucleotidase whereas compound 4a also active but less potent inhibitor. Compound 4b is the most potent inhibitor of phosphoribosyl pyrophosphate (PPRP) synthetase which follows by 4c, 4d and 4a. All of these compounds were more potent inhibitor of PPRP-synthetase than ADP or GDP. Ribavirin imidodiphosphate (4e) was also synthesized and tested for its inhibitory effect on ecto-5'-nucleotidase, PPRP-synthetase as well as IMP dehydrogenase. Compound 4e is the most potent inhibitor of IMP dehyrogenase but was a weak inhibitor of the other two enzymes. compound 4a, 4b, 4c and 4d are weak inhibitors of IMP dehydrogenase.