Hydrophobised sawdust as a carrier for immobilisation of the hydrocarbon-oxidizing bacterium Rhodococcus ruber

Pine sawdust treated by a series of hydrophobising agents (drying oil, organosilicon emulsion, n-hexadecane and paraffin) was examined as carrier for adsorption immobilisation of hydrocarbon-oxidizing bacterial cells Rhodococcus ruber. It was shown that hydrophobising agents based on drying oil turned out to be optimal (among the other modifiers examined) for the preparation of sawdust carriers suitable for the efficient immobilisation. The results obtained demonstrate promising possibilities in developing a wide range of available and cheap, biodegradable cellulose-containing carriers that possess varying surface hydrophobicity.     

Relationships between silicon content and glutathione peroxidase activity in tissues of rats receiving lithium in drinking water

Lithium salts are widely used in psychiatry, but their presence in organism can result in both beneficial and adverse effects. Silicon, the third most abundant trace element in humans as well as antioxidant enzyme glutathione peroxidase (GPx) play important roles in organism. The disturbance of their level can cause severe disorders. The aim of our work was to evaluate the influence of Li₂CO₃ administration in drinking water for a period of 4 weeks on Si content and GPx activity in the tissues of liver, kidney, brain and femoral muscle in rats. The concentrations of provided solutions were 0.7, 1.4, 2.6, 3.6, 7.1 and 10.7 mmol Li⁺·dm⁻³. GPx activity was decreased versus control as a consequence of Li treatment, particularly in kidney and brain. This effect could be suggested to contribute to renal abnormalities which could occur during Li therapy. Si tissue level was significantly enhanced versus control in liver and femoral muscle in groups receiving high Li doses. In brain no well-marked changes were observed, whereas in kidney we observed the depletion in low-Li-groups, restoration of Si level in higher-Li-groups and unexpected decrease in the highest-Li-group. Positive correlations between Si content and GPx activity in the tissues of kidney (r = 0.677) and brain (r = 0.790) as well as negative correlation (r = −0.819) in femoral muscle were found. We consider that our results give some reason for suggesting that monitoring of silicon level in patients undergoing Li therapy could be recommended. However, more investigations should be performed, particularly regarding the relationships between Si and GPx in blood and urine Si excretion during lithium administration.     

oxLDL facilitates flow-induced realignment of aortic endothelial cells

Alignment of vascular endothelial cells (ECs) in the direction of the flow is considered a key factor in maintaining endothelial integrity in an active hemodynamic environment. Our recent studies showed that exposure to oxidized LDL (oxLDL), one of the major proatherogenic lipoproteins, significantly increases the stiffness of human aortic ECs, suggesting that oxLDL may have a significant impact on the sensitivity of ECs to mechanical stimuli. In this study, we show that oxLDL strongly enhances the ability of ECs to realign in the direction of the flow and facilitates the formation of F-actin stress fibers under static and flow conditions. The impact of oxLDL on the flow-induced realignment is observed on whole cell and single-fiber levels. We also show that, similar to the effect of oxLDL on endothelial stiffness, the impact of oxLDL on flow-induced realignment can be simulated by methyl-beta-cyclodextrin-induced cholesterol depletion, supporting the hypothesis that oxLDL acts as cholesterol acceptor, rather than cholesterol donor, for ECs. Finally, we propose that oxLDL/cholesterol depletion-induced sensitization of ECs to flow may be a result of an increase in cellular stiffness and a respective increase in membrane-cytoskeleton tension.     

Cryptic peptide derived from the rat neuropeptide FF precursor affects G-proteins linked to opioid receptors in the rat brain

Recently, we reported the discovery of a novel amino acid sequence derived from the NPFF precursor NAWGPWSKEQLSPQA, which blocked the expression of conditioned place preference induced by morphine and reversed the antinociceptive activity of morphine (5mg/kg, s.c.) in the tail-immersion test in rats. Here, we name it as NPNA (Neuropeptide NA from its flanking amino acid residues). The synthetic peptide influenced the expression of mRNA coding for Galpha(i1), (i2), and (i3) subunits. The results provide further evidence that yet another bioactive sequence might be present within the NPFF precursor.     

Bioremediation of Crude Oil-Contaminated Soil Using Slurry-Phase Biological Treatment and Land Farming Techniques

Field-scale experiments on bioremediation of soil heavily contaminated with crude oil were undertaken on the territory of the Kokuyskoye oil field (Perm region, West Urals, Russia) owned by the LUKOIL Company. The pollution consisted of the contents of a oil waste storage pit, which mostly received soils contaminated after accidental oil spills and also the solid n-alkane (paraffin) wastes removed from the surface of drilling equipment. Laboratory analyses of soil samples indicated contamination levels up to 200?g/kg of total recoverable petroleum hydrocarbons (TRPH). Average oil composition consisted of 64% aliphatics, 25% aromatics, 8% heterocyclics, and 3% of tars/asphaltenes. Ex situ bioremediation techniques involved the successive treatment of contaminated soil using a bioslurry reactor and land farming cells. An oleophilic biofertilizer based on Rhodococcus surfactant complexes was used in both treatment systems. An aerobic slurry bioreactor was designed, and the biofertilizer applied weekly. Slurry-phase biotreatment of the contaminated soil resulted in an 88% reduction in oil concentration after 2 months. The resulting reactor product, containing approximately 25?g/kg of TRPH, was then loaded into land farming cells for further decontamination. To enhance bioremediation, different treatments (e.g., soil tilling, bulking with woodchips, watering, and biofertilizer addition) were used. The rates of oil biodegradation were 300 to 600?ppm/day. As a result, contamination levels dropped to 1.0 to 1.5?g/kg of TRPH after 5 to 7 weeks. Tertiary soil management involved phytoremediation where land farming cells were seeded with a mixture of three species of perennial grass. The effect of phytoremediation on the residual decontamination and rehabilitation of soil fertility is being evaluated.     

Increased solubility of lamins and redistribution of lamin C in X-linked Emery–Dreifuss muscular dystrophy fibroblasts

Emery–Dreifuss muscular dystrophy (EDMD) is caused by mutations in the gene encoding the nuclear membrane protein emerin (X-linked EDMD) or in the gene encoding lamins A/C (autosomal dominant EDMD). One hypothesis explaining the disease suggests that the mutations lead to weakness of the nuclear lamina. To test this hypothesis we investigated lamin solubility and distribution in skin fibroblasts from X-EDMD patients. Using in situ extraction of cells and immunofluorescence microscopy or biochemical fractionation and immunoblotting, we found that all lamin subtypes displayed increased solubility properties in fibroblasts from X-EDMD patients compared to normal individuals. Lamin and emerin solubility was mildly increased in fibroblasts from an X-EDMD carrier. Biochemical fractionation and immunoblotting also indicated that lamin C but no other lamin became redistributed from the nuclear lamina to the nucleoplasm in X-EDMD fibroblasts. Indirect immunofluorescence and confocal microscopy studies using lamin A- and lamin C-specific antibodies confirmed that lamin C but not lamin A became redistributed to the nucleoplasm. Interestingly, the lamin A/C binding protein LAP2α was also mislocalized in X-EDMD fibroblasts.     

Invertebrate population genetics across Earth's largest habitat: The deep‐sea floor

Despite the deep sea being the largest habitat on Earth, there are just 77 population genetic studies of invertebrates (115 species) inhabiting non‐chemosynthetic ecosystems on the deep‐sea floor (below 200 m depth). We review and synthesize the results of these papers. Studies reveal levels of genetic diversity comparable to shallow‐water species. Generally, populations at similar depths were well connected over 100s–1,000s km, but studies that sampled across depth ranges reveal population structure at much smaller scales (100s–1,000s m) consistent with isolation by adaptation across environmental gradients, or the existence of physical barriers to connectivity with depth. Few studies were ocean‐wide (under 4%), and 48% were Atlantic‐focused. There is strong emphasis on megafauna and commercial species with research into meiofauna, “ecosystem engineers” and other ecologically important species lacking. Only nine papers account for ~50% of the planet's surface (depths below 3,500 m). Just two species were studied below 5,000 m, a quarter of Earth's seafloor. Most studies used single‐locus mitochondrial genes revealing a common pattern of non‐neutrality, consistent with demographic instability or selective sweeps; similar to deep‐sea hydrothermal vent fauna. The absence of a clear difference between vent and non‐vent could signify that demographic instability is common in the deep sea, or that selective sweeps render single‐locus mitochondrial studies demographically uninformative. The number of population genetics studies to date is miniscule in relation to the size of the deep sea. The paucity of studies constrains meta‐analyses where broad inferences about deep‐sea ecology could be made.     

Radical‐scavenging activity of penicillin G,ampicillin, oxacillin,and dicloxacillin

The aim of this study was to characterize the antioxidant activity of penicillin G (PG), ampicillin (AMP), oxacillin (OX) and dicloxacillin (DOX) through their reactivity towards reactive oxygen species (superoxide anion radical, ; hydroxyl radical, HO^?; peroxyl radical, ROO^?; hydrogen peroxide, H₂O₂; DPPH^?) using various in vitro antioxidant assays with chemiluminescence (CL) and spectrophotometry as measurement techniques. In hydroxyl radical assays , PG, OX and AMP were found to inhibit the CL signal arising from the Fenton‐like reaction in a dose‐dependent manner with IC₅₀ = 0.480 ± 0.020 mM, IC₅₀ = 0.569 ± 0.021 mM, and IC₅₀ = 0.630 ± 0.019 mM, respectively. The highest reactivity of PG among the tested penicillins towards the HO radical was confirmed in the deoxyribose degradation assay. In the ABAP‐derived ROO radical assay, the radical‐scavenging ability of the test penicillins was in the following order: AMP > PG > DOX > OX. The number of reduced DPPH radicals by the drugs tested was <1 being the biggest for PG. The weak antioxidant capacity of the test penicillins was confirmed in the trolox antioxidant capacity assay (0.075 ± 0.004; 0.093 ± 0.006; 0.123 ± 0.005; 0.126 ± 0.004) for OX, AMP, DOX, PG, respectively. Use of luminol as a CL probe for estimation of penicillin reactivity towards H₂O₂ showed that only AMP was able to quench light emission; the remaining antibiotics demonstrated a strong enhancing effect. All the examined compounds showed a weak antioxidant potential when estimated using the ferric‐ferrozine assay. This study is the first to report the evaluation of test penicillins as antioxidants under the same reaction conditions.     

Synthesis and in vitro antioxidant activity study of some new piperazinyl flavone compounds

Flavones exhibit a variety of beneficial effects and are well known for their medicinal importance in several diseases, including cardiovascular, neurodegenerative and cancer. The inclusion of the piperazine ring to the flavone backbone is an important strategy in drug discovery but only a few studies have synthesized piperazinyl flavone compounds to test their biological activity. While there is a major focus on the antioxidant properties of drugs in therapy of several diseases of inflammatory origin, we synthesized a series of the novel piperazinyl flavone analogues bearing the phenyl ring with different substituents. The analogues were evaluated for in vitro antioxidant activity against superoxide anion radical, hydroxyl radical, 2,2‐diphenyl‐1‐picrylhydrazyl radical, and hydrogen peroxide scavenging properties. The total antioxidant status based on the absorbance of the 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) radical cation (ABTS^+?) and total antioxidant capacity using the Fe(III)‐ferrozine complex were also monitored. The results of the above studies showed that the compounds synthesized were found possessed moderate radical scavenging potential, and that their interaction with reactive oxygen species is complex and depends on their structural conformation and the type of substituent R in the piperazine ring being attached. Best antiradical activity were found for the compounds with methoxy groups on the phenyl ring of substituent R, whereas the presence of methoxy or trifluoromethyl groups in substituent R resulted in higher ABTS^+? and ion Fe(III) reduction. These compounds are promising molecules to be used for their antioxidant properties and may be regarded, after improvement of the antioxidant potential, to control diseases of free radical etiology.