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Subcutaneous dirofilariosis is a zoonotic disease emerging throughout Europe caused by the filarial nematode Dirofilaria repens. Despite its increasing prevalence, there is a large gap in knowledge of the impact of the parasite on the host. Currently classified as being non-pathogenic, recent evidence suggests that skin dirofilariosis is associated with dermatological conditions including concomitant pruritus, neoplastic processes, inflammation, and even blindness in dogs and humans. The aim of this study was to determine if natural canine D. repens infection leads to biological changes in the canine host. In a real-life veterinary clinic setting, animals are often presented to clinicians for unrelated issues, and D. repens is incidentally identified during inspection. As such, we compared hematological and biochemical parameters of 218 uninfected and 197 dogs naturally infected with D. repens. Interestingly, animals infected with D. repens had lower numbers of lymphocytes (p < 0.001), red blood cells (p < 0.001), and thrombocytes (p = 0.025), decreased hematocrit (p < 0.001), and increased alkaline phosphatase (p = 0.016) and creatinine activity (p = 0.023) compared to uninfected dogs. We further selected a subpopulation of 214 dogs having prima facie hematological and biochemical results within normal reference ranges to evaluate the effect of D. repens infections in seemingly healthy dogs. Among these patients, 93 dogs infected with D. repens had lower numbers of lymphocytes (p = 0.031), red blood cells (p = 0.025), and hematocrit (p = 0.002), higher glucose levels (p = 0.023), and border line elevated alkaline phosphatase levels (p = 0.054) compared to 121 uninfected animals. Despite being categorized as asymptomatic, we have observed hematological and biochemical changes associated with D. repens infections in dogs, and our data suggest that dirofilariosis may induce a state of chronic stress. These results link the presence of skin dirofilariosis to biological changes in the canine host, suggesting a mechanism for pathogenicity and shedding new light on the host–parasite relationship.

Mammary tumors are the second most common neoplasia in dogs. Due to the high similarity of canine mammary tumors (CMT) to human breast cancers (HBC), human biomarkers of HBC are also detectable in cases of CMT. The evaluation of biomarkers enables clinical diagnoses, treatment options and prognosis for bitches suffering from this disease. The aim of this article is to give a short summary of the biomarkers of CMT based on current literature. Very promising biomarkers are miRNAs, cancer stem cells, and circulating tumor cells, as well as mutations of the breast cancer 1 gene (BRCA1) and breast cancer 2 gene (BRCA2). Until now, the most studied and reliable biomarkers of CMT have remained antigen Ki-67 (Ki-67), endothelial growth factor receptor, human epidermal growth factor receptor 2 (HER-2), estrogen receptor, progesterone receptor and cyclooxygenase 1 (COX-2), which can be detected in both serum and tissue samples using different molecular methods. However, carcinoembryonic antigen and cancer antigen 15-3 (CA 15-3), while poorly studied, seem to be good biomarkers, especially for the early detection and prognosis of CMT. We will also mention the following: proliferative cell nuclear antigen, tumor protein p53 (p53), E-cadherin, vascular endothelial growth factor, microRNAs, cancer stem cells and circulating tumor cells, which can also be useful biomarkers. Although many studies have been conducted so far, the estimation of biomarkers in cases of CMT is still not a common practice, and more detailed research should be done.

Diamond and/or carbon thin films are in the center of interest due to their variability and extraordinary combination of intrinsic properties. However, some applications require fabrication of films with tailored properties. Especially, fabrication of periodic structures is highly attractive due to their increased surface area. In this contribution we point out the key technological aspects for fabrication of micro- and nano-sized carbon-based structures. Three representative structures are presented: diamond nanorods, self-assembled templates and self-standing diamond membranes. We found that the diameter of diamond nanorods can be controlled in a broad range from 10 to 200 nm by the masking material (Au vs Ni) and its initial thickness (from few to tens of nanometers). The assembly of polystyrene microspheres in mono- or multi-layer with square or hexagonal periodicities was controlled by the spin-coating parameters. The diamond porous membrane was selectively grown on Si substrate with an interdigital or mesh like geometry. Advantages of each structure as well as the fabrication limitations are discussed more in detail and finally their representative applications are pointed out. K e y w o r d s: diamond, carbon, nanorods, microsphere lithography, selective area deposition, SEM

Eukaryotic genomes contain vast amounts of repetitive DNA derived from transposable elements (TEs). Large-scale sequencing of these genomes has produced an unprecedented wealth of information about the origin, diversity, and genomic impact of what was once thought to be “junk DNA.” This has also led to the identification of two new classes of DNA transposons, Helitrons and Polintons, as well as several new superfamilies and thousands of new families. TEs are evolutionary precursors of many genes, including RAG1, which plays a role in the vertebrate immune system. They are also the driving force in the evolution of epigenetic regulation and have a long-term impact on genomic stability and evolution. Remnants of TEs appear to be overrepresented in transcription regulatory modules and other regions conserved among distantly related species, which may have implications for our understanding of their impact on speciation.

Alu and L1 are families of non-LTR retrotransposons representing approximately equal 30% of the human genome. Genomic distributions of young Alu and L1 elements are quite similar, but over time, Alu densities in GC-rich DNA increase in comparison with L1 densities. Here we analyze two processes that may contribute to this phenomenon. First, DNA duplications in the human genome occur more frequently in Alu- and GC-rich than in AT-rich chromosomal regions. Second, most Alu elements tend to be coclustered with each other, but recently retroposed elements are likely to be inserted outside the existing clusters. These "stand-alone" elements appear to be rapidly eliminated from the genome. We also report that over time, the densities of recently retroposed Alu families on chromosome Y decline rapidly, whereas Alu densities on chromosome X increase relative to autosomal densities. We propose that these changes in the chromosomal proportions of Alu densities and the elimination of stand-alone Alus represent the same process of paternal Alu selection. We also propose that long-term Alu accumulation in GC-rich DNA is associated with DNA duplication initiated by elevated recombinogenic activities in Alu clusters.

Bi-layer graphene sheets have been prepared on the basis of a reaction of cobalt with silicon carbide at temperatures around 1,000 °C. This is a type of viable low temperature graphene synthesis. Preparation of graphene was carried out with various thicknesses of the Co layer deposited onto the SiC surface and parameters of the annealing process (temperature, annealing time) were varied. Number of carbon mono-layers in the prepared graphene and its crystallinity were determined from the results of Raman spectroscopy. The best results have been obtained for a structure with Cobalt layer of 300 nm thickness, annealed at 1,080 °C for the period of 120 s. When using shorter annealing times, significantly non-homogenous reaction of Co with SiC has been observed, forming two different phases on the surface.

The aim of this study was to test the hypothesis that exercise would induce inflammatory response characterized by increased pro-inflammatory cytokines - interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α), adhesion molecule, matrix metalloprotease-9 (MMP-9) and myeloperoxidase (MPO) levels. Additional aim was to elucidate the possible source of maximal exercise-induced increase in MMP-9 concentration. To examine our hypothesis, 26 professional male ice hockey players [age 25 ± 1 (mean ± SEM) years; BMI 25.8 ± 0.4 kg/m(2) ] performed an incremental bicycle test until exhaustion, when maximal oxygen consumption was recorded. Venous blood samples were collected 30 min before and 2 min after exercise. There was an increase in the count of leucocytes (8.7 ± 1.8 versus 5.7 ± 1.3 × 10(9) cells per l) and IL-6 (1.24 ± 0.17 versus 0.69 ± 0.13 pg/ml), MPO (72 ± 7 versus 50 ± 4 ng/ml) and MPP-9 (139 ± 9 versus 110 ± 6 ng/ml) concentrations (P < 0.05) comparing post- and pre-exercise levels. Maximal exercise-induced increase in MPO correlated with the increases in IL-6 (P < 0.05, R = 0.54) and MMP-9 (P < 0.01, R = 0.62) concentrations. Furthermore, increase in IL-6 correlated with the increase in MMP-9 concentrations (P < 0.05, R = 0.60). Maximal exercise induces an inflammatory response characterized by leucocytosis and increased IL-6, MPO and MMP-9 concentrations. Correlations between increased MPO (marker of neutrophils degranulation) and both increased IL-6 and MMP-9 concentrations may suggest that neutrophils could be the main source of these inflammatory biomarkers during maximal exercise. Furthermore, correlation between increases in serum IL-6 and MMP-9 concentrations may suggest that IL-6 could exert modulatory effects on MMP-9 release during maximal exercise.

2% Rh–CeO 2 catalyst was synthesized using the hard template method and characterized by means of N 2 adsorption/desorption, XRD and H 2 -TPR methods. The prepared powdered catalyst exhibited high thermal stability and high surface area with negligible sintering during 24-h exposure to 973 K in an inert atmosphere. During the temperature programmed methane dry reforming reaction between 473 and 1073 K, an increase in the molar H 2 /CO ratio from 0.3 at 623 K to as high as 0.96 at 1073 K was observed. Besides H 2 and CO, H 2 O was identified among reaction products, originating from the simultaneously occurring reverse water-gas shift reaction. During the isothermal test performed at 923 K, the 2% Rh–CeO 2 catalyst exhibited stable performance and produced syngas with the average H 2 /CO ratio equal to 0.62. A relative drop of catalyst activity equal to 11% was observed within 70-h time on stream at 1023 K, with the average H 2 /CO ratio at the reactor outlet equal to 0.71.

There are many pathophysiological mechanisms underlying reciprocal relationships between changes in cytokines and insulin resistance in metabolic and cardiovascular disorders. The aim of this study was to evaluate alterations in soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble E-selectin (sE-selectin), matrix metalloproteinase-9 (MMP-9), plasminogen activator inhibitor-1 (PAI-1), and myeloperoxidase (MPO) levels, and their relation to insulin resistance in coronary artery disease (CAD) patients with stable and unstable angina (SAP, UAP).Non-diabetic CAD patients were classified into two groups: 22 patients with SAP and 22 patients with UAP. 22 healthy subjects were selected as controls. The study groups were matched for age and sex. Insulin resistance was evaluated by HOMA-IR method. Serum levels of sICAM-1, sVCAM-1, sE-selectin PAI-1(total), MPO and MMP-9 were quantified by xMAP technology (Luminex-200 analyzer).Both patient groups demonstrated significantly elevated serum levels of sICAM-1, sE-selectin, PAI-1(total), MPO and MMP-9 (p0.05) as well as higher IR-HOMA values (p0.05) than those of healthy controls. The elevation was more pronounced in the UAP group (p0.01). HOMA-IR was correlated with sICAM-1, PAI-1(total), and MMP-9 (p0.01).Our findings show that CAD patients have elevated HOMA-IR values. Furthermore, CAD patients with UAP have higher levels of sICAM-1, sVCAM-1, sE-selectin, MMP-9, PAI-1(total), and MPO than patients with SAP, and there are relationships between three of the above biomarkers: sICAM-1, PAI-1(total), MMP-9 and HOMA-IR.

Neopterin, cellular adhesion molecules and myeolperoxidase in patients with stable and unstable angina pectoris Recent data indicate that the serum level of neopterin, a marker of inflammation and immune modulator secreted by monocytes/macrophages, is elevated in patients with acute coronary syndrome (ACS) and seems to be a prognostic marker for major cardiovascular events. Soluble cellular adhesion molecules (sCAMs) and myeloperoxidase (MPO) levels are also related to ACS. The aim of the present study was to evaluate differences in serum levels of neopterin, sCAMs and MPO between coronary artery disease and metabolic syndrome (CAD-MetS) patients with stable and unstable angina pectoris (SAP, UAP), and to clarify the relationships between neopterin and other biomarkers. The study included 60 patients with CAD-MetS who were classified into two groups, 30 patients with SAP and 30 patients with UAP. Twenty healthy subjects were selected as controls (C). Serum soluble vascular cell adhesion molecule-1 (sVCAM-1), intercellular cell adhesion molecule-1 (sICAM-1), sE-selectin and MPO levels were measured by Luminex xMAP technology, and serum neopterin concentrations were measured by radioimmunoassay. Results: Serum levels of neopterin, MPO, sVCAM-1, sICAM-1, and sE-selectin were significantly higher in patients with UAP in comparison with the group of healthy controls (P < 0.05). Patients with SAP also had higher levels of these biomarkers than those in healthy controls (P < 0.05), except for sE-selectin. The biomarker level did not differ between the two patient groups, except for MPO, which was significantly higher in the USP group (P < 0.05). Neopterin was significantly correlated only with sVCAM-1 (P < 0.05). In conclusion, CAD-Met patients with SAP had more apparent raised levels of serum sICAM-1 and sVCAM-1, simultaneously with higher MPO and neopterin concentrations, in comparison to those in healthy subjects. However, UAP is also associated with more substantial changes in MPO and significantly increased sE-selectin levels. Neopterin concentration was had a close correlation only with sVCAM-1.

The aim of this study was to evaluate the influence of elevated temperature on bovine oviduct epithelial cells (BOECs), based on the expression and localization of both heat shock protein 70 (HSP70), responsible for the cellular defence mechanism, and oviduct specific glycoprotein 1 (OVGP1) which is the most important embryotrophic protein. BOECs were cultured alone and co-cultured with cattle embryos at control (38.5°C) and elevated temperature (41°C) for 168 h. The elevated temperature had no effect on the viability of BOECs but exerted a negative effect on embryo development. The elevated temperature increased the expression of HSP70 and decreased the expression of OVGP1 at both mRNA and protein levels in BOECs cultured alone and those co-cultured with embryos. However, the presence of embryos limited the decrease in OVGP1 expression in BOECs at elevated temperature but did not alter the expression of HSP70. These results demonstrate for the first time the influence of elevated temperature on BOECs, consequently providing insights into the interactions between the embryo and the oviduct at elevated temperature.

We demonstrate a metamaterial exhibiting a frequency-tunable response in the terahertz domain, controlled by a bias electric field. The active part of the metamaterial consists of a periodic metallic pattern deposited on a thin epitaxially strained strontium titanate film. The role of the metallic structure is two-fold: it gives rise to the metamaterial resonance and it enables applying an electric bias to the strontium titanate layer. The strained film exhibits a pronounced dependence of its permittivity on the bias, which exerts a strong influence on the resonance. Specifically, the resonance of our structure occurs near 0.5 THz and, upon applying a bias voltage of 55 V, a relative tunability of the resonance frequency of 19% was achieved at room temperature.

Fourteen female cats with fibroadenomatosis were treated with aglepristone, and the effectiveness of the treatment and its effect on selected haematological and blood chemistry parameters were studied. The cats were monitored for 12 months after the end of the treatment. Complete remission of the clinical signs was achieved on average 3.9 weeks after the treatment began; the success of the treatment confirmed the clinical diagnosis of fibroadenomatosis. During the course of the treatment the cats' haematological parameters returned to normal. In cats that had previously been treated with long-acting medroxyprogesterone acetate, treatment with aglepristone for five weeks was recommended. Cases of fibroadenomatosis reappearing after a few months should be regarded as new disease rather than a relapse. Six cats were subsequently mated and four gave birth to one or more litters; all the pregnancies proceeded normally with no clinically evident fibroadenomatosis. The other eight cats underwent ovariohysterectomy soon after the aglepristone treatment was completed.

This study focuses on water–gas shift reaction (WGSR) activity of CuO–CeO 2 catalysts containing 10, 15 and 20 mol% CuO synthesized by hard template method with KIT-6 silica acting as a template. The obtained solids were characterized by N 2 adsorption/desorption, XRD, H 2 -TPR/TPD, N 2 O decomposition, in situ DRIFTS and NH 3 chemisorption/TPD methods. The catalysts exhibited ordered mesoporous structure, which was identified as the negative replica of KIT-6 silica pore system with CuO dispersion values between 28 and 40%. H 2 -TPR/TPD experiments revealed facile and extensive CeO 2 reduction in tested samples, which increased with CuO loading, indicating strong interactions between both oxide phases. On the other hand, abundance of surface acidic sites decreased with increasing CuO content. WGS reaction activity was tested at the stoichiometric CO/H 2 O ratio and low contact times in the temperature range from 250 to 450 °C. At reaction temperatures above 375 °C, catalyst deactivation was observed, regardless of CuO content. Despite rigorous reaction conditions, CO conversion up to 62% was attained, with H 2 selectivity above 99% in the entire temperature range.

Carbon nanofibers (CNF) synthesized by catalytic chemical vapor deposition (CVD) method were used to prepare supported platinum, palladium and ruthenium monometallic (2.0 wt.%) catalysts by means of incipient-wetness impregnation method. The CNF support and catalysts were characterized by X-ray powder diffraction (XRD), nitrogen adsorption/desorption isotherms, volumetric chemisorption of hydrogen, temperature-programmed reduction (H2-TPR) and scanning electron microscopy (SEM). Solids were tested in catalytic wet-air oxidation (CWAO) of phenol aqueous solution (180–240 °C and 10.0 bar of oxygen partial pressure) carried out in a continuous-flow trickle-bed reactor. Trends of phenol and total organic carbon (TOC) conversion demonstrate that the CNF support and CNF-Pt catalyst did not exhibit constant activity for CWAO of phenol. A decrease of catalyst activity, detection of carbon dioxide in the off-gas stream while examining catalyst stability and significant textural changes observed, provide an evidence that under net oxidizing reaction conditions gasification of the CNF support occurs. The prepared catalysts were also tested in liquid-phase thermal decarboxylation of formic acid in inert atmosphere (60–220 °C). Among solids examined, the CNF-Pd exhibited the highest activity. At the employed conditions, no decomposition of the CNF support was observed during the thermal decarboxylation of formic acid.

This study focuses on the characterization and water–gas shift reaction (WGSR) activity of CuO-CeO 2 catalysts containing 10, 15 and 20 mol% CuO synthesized by hard template method (HT) with KIT-6 silica acting as a template and co-precipitation method (CP). The obtained solids were characterized by SEM/TEM microscopy, N 2 adsorption/desorption, XRD, H 2 -TPR/TPD, N 2 O decomposition and NH 3 chemisorption/TPD methods. The preparation techniques yield fundamentally different products despite the same nominal chemical composition. Catalysts prepared by the HT method exhibited ordered mesoporous structure, which was identified as the negative replica of the KIT-6 silica pore system. Considerable differences in BET surface area (147–166 m 2 /g for CuCe HT samples compared to 22–54 m 2 /g for CuCe CP solids, respectively) were measured. CuO dispersion values between 28% and 40% were determined for CuCe HT solids, in case of CuCe CP samples, these values were in the range of 8–20%. H 2 -TPR/TPD experiments revealed facile and extensive CeO 2 reduction in all tested samples, which increased with CuO loading. Very similar density of surface acidic sites was determined for both CuCe HT and CuCe CP catalyst samples at each CuO loading, with CuCe CP solids exhibiting the absence of strong acidic sites. WGS reaction activity was tested at the stoichiometric CO/H 2 O ratio and low contact times in the temperature range from 250 to 450 °C. Despite rigorous reaction conditions, CO conversions up to 62% and 54% were attained for CuCe HT and CuCe CP samples, respectively, with H 2 selectivity above 99% over the entire temperature range. Superior BET surface area and CuO dispersion of CuCe HT samples are decisive factors contributing to higher activity in the investigated WGS reaction, compared to the ones synthesized by the co-precipitation method.

The inelastic mean free paths (IMFPs) of electrons at a poly[methyl(phenyl)silylene] thin film surface were determined using elastic peak electron spectroscopy (EPES) and Monte Carlo calculations for a wide electron energy range, 200–1600 eV. We considered the surface composition determined from X-ray induced photoelectron spectra (XPS), the hydrogen concentration evaluated by EPES, and a correction for surface excitations. The results compare well to those calculated from the predictive TPP-2M and G1, formulae. Calculations carried out with the quantitative structure–property relationship of Cumpson and the formula of Ashley and Williams provide larger IMFP values, and can be useful only for a rough estimation.

The cystic endometrial hyperplasia and pyometra complex is one of the most common uterine diseases in bitches. The appearance of pharmacological preparations containing anti-progestagens created new possibilities for pyometra treatment. The aim of this study was to evaluate the curative effect of the anti-progestagen aglepristone treatment of pyometra in bitches of different ages. Twenty four bitches of different breeds, aged from 0.8 to 9.5 years (21-48 kg) exhibiting clinical pyometra symptoms (two groups - I 5 years, n = 10) were evaluated. Information about the general reproductive health was collected up to 54 months after anti-progestagen treatment. Remission of clinical symptoms and return of blood chemistry results and total leucocyte count to referential values were achieved in all cases within 14 days of treatment. Bitches were naturally mated at the first, and when unsuccessful, the second oestrus after treatment. In group I, no recurrence of pyometra symptoms was observed during following cycle(s). Eight bitches (57.1%) had a full-term pregnancy and the number of newborn pups ranged from 1 to 12. None of the bitches from the group II became pregnant. In conclusion, the basic indication for conservative pharmacological treatment of pyometra is preserving female fertility and obtaining offspring. The important conditions for successful aglepristone treatment are: the young age (up to 5 years) and the lack of detectible ovarian cysts. It seems necessary to mate bitches in the first or second oestrus after finishing treatment. The efficacy of treatment can be measured by the after-treatment pregnancy rate.

Catalytic wet-air oxidation of aqueous solutions of formic acid, acetic acid and phenol was carried out in a trickle-bed reactor at T = 328–523 K and total pressures up to 50 bar over various Ru/TiO 2 catalysts. Complete oxidation of formic acid was obtained at mild operating conditions, and no catalyst deactivation occurred that could be attributed to the dissolution of active ingredient material. It was observed that besides oxidation route thermal decomposition contributes significantly to the removal of formic acid; Ru/TiO 2 catalysts could be thus efficiently used for transformation of HCOOH to H 2 and CO 2 in an inert atmosphere. Liquid-phase oxidation of acetic acid was found to be structure sensitive; the highest catalyst activity was obtained, when Ru phase on the catalyst surface prevailed in zero-valent state. Due to simultaneous oxidation of metallic Ru to RuO 2 during the reaction course, correspondingly lower conversion of acetic acid was measured in the reactor outlet. The employed Ru/TiO 2 catalysts enable complete removal of phenol and TOC at temperatures above 483 K; at these conditions, no carbonaceous deposits were accumulated on the catalyst surface. Apparent catalyst deactivation observed at temperatures below 463 K is attributed to strong adsorption of partially oxidized intermediates on the catalyst surface, which can be avoided by conducting the CWAO process at sufficiently high temperatures. The acute toxicity to Daphnia magna and Vibrio fischeri of end-product solutions compared with that of the feed solutions was significantly reduced by oxidative treatment over Ru/TiO 2 catalysts.

In this work we investigated the influence of CuO loading and catalyst pretreatment procedure to derive an optimal CuO-CeO2 catalyst for water-gas shift (WGS) reaction, and to study in detail structure–activity relationships. Nanostructured catalyst samples prepared by co-precipitation and a 10, 15 and 20 mol% CuO content were examined by XRD, BET and TPR/TPD analyses and subjected to pulse WGS activity tests in the temperature range of 180–400 °C. As evaluated by TPR/TPD and N2O chemisorption analyses, with increasing CuO loading the portion of finely dispersed CuO nanoparticles decreases on behalf of larger CuO aggregates. Strong surface structure–activity dependence in WGS reaction was observed for all catalyst samples. It was established that increasing CuO content results in higher extent of CeO2 reduction, which has a positive effect on H2 production during the WGS reaction. Increasing calcination temperature on the other hand reduces BET surface area, induced by CuO sintering and agglomeration of CeO2 particles resulting in a negative effect on H2 production. Distinctive WGS activity dependence on surface acidity of examined solids was observed for all CuO loadings.

CE with capacitively coupled contactless detection (C4D) was used to determine 3-methylhistidine (3-MH) and 1-methylhistidine (1-MH). The C4D response to 3-MH was studied in a BGE consisting of 500 mM acetic acid and ammonia at varying concentration and the results were compared with the theory. Complete separation of a model mixture of 3-MH, 1-MH, and histidine (His) was attained in two optimized BGEs, one containing 500 mM HAc, 20 mM NH4OH, and 0.1 % m/v hydroxyethylcellulose (HEC), pH 3.4 (I) and the other consisting of 100 mM morpholinoethanesulfonic acid (MES), 25 mM LiOH, and 0.1 % m/v HEC, pH 5.5 (II). These optimized BGEs were tested in CE/C4D analyses of urine. Promising results were obtained for separation and determination of 3-MH, 1-MH, and His on a silicon microchip, using aluminum strips as the C4D electrodes; the three analytes were baseline-separated within less than 30 s with a separation channel effective length of 38 mm. The LOD were satisfactory and amounted to 26.4 microM for 3-MH and 18.3 microM for 1-MH.

Cu(x)Ce(1-x)O(2-y) mixed oxide catalysts were prepared by different preparation procedures: co-precipitation, the sol-gel peroxide route, and the sol-gel citric acid-assisted route. The resulting solids were investigated by means of XRD, BET, H(2) and CO temperature-programmed reduction (TPR), oxidation (TPO) and desorption (TPD) analyses, and N(2)O pulse selective reaction. It was confirmed that H(2) (CO) consumed for complete reduction of well-dispersed and bulk-like CuO phases to Cu(0), reduction of surface ceria and H(2) (CO) adsorption on the catalyst surface contribute to the total H(2) (CO) consumption. Among catalysts examined, the Cu(0.15)Ce(0.85)O(2-y) mixed oxide sample prepared by means of co-precipitation method exhibits the highest activity and stability for water-gas shift (WGS) pulse reaction in the range of employed operating conditions. WGS activity of copper-ceria mixed oxide catalysts is determined by the extent of surface ceria reduction and dispersion of copper species.

DNA methylation has important functions in stable, transcriptional gene silencing, immobilization of transposable elements and genome organization. In Arabidopsis, DNA methylation can be induced by double-stranded RNA through the RNA interference (RNAi) pathway, a response known as RNA-directed DNA methylation. This requires a specialized set of RNAi components, including ARGONAUTE4 (AGO4). Here we show that AGO4 binds to small RNAs including small interfering RNAs (siRNAs) originating from transposable and repetitive elements, and cleaves target RNA transcripts. Single mutations in the Asp-Asp-His catalytic motif of AGO4 do not affect siRNA-binding activity but abolish its catalytic potential. siRNA accumulation and non-CpG DNA methylation at some loci require the catalytic activity of AGO4, whereas others are less dependent on this activity. Our results are consistent with a model in which AGO4 can function at target loci through two distinct and separable mechanisms. First, AGO4 can recruit components that signal DNA methylation in a manner independent of its catalytic activity. Second, AGO4 catalytic activity can be crucial for the generation of secondary siRNAs that reinforce its repressive effects.

A novel scheme of integrated ion-exchange/catalytic denitrification process for the removal of excessive quantities of nitrate ions from groundwater is proposed, which employs two separate reactor units to considerably minimize the production of ammonium ions as a side product in subsequent regeneration cycles. In the first reactor unit, selective reduction of nitrates to nitrites is carried out at high pH value (above 11.0) in the presence of Pd-Cu/γ-Al2O3 bimetallic catalyst. At T = 298 K and hydrogen partial pressure of 1.0 bar, up to 97% transformation of nitrates to nitrites was obtained, even at complete conversion of nitrate ions; the rest was found in the form of ammonium ions. In the second reactor unit, selective reduction of nitrites to nitrogen takes place at low pH value (4.5) over a Pd/γ-Al2O3 monometallic catalyst. A catalyst with higher dispersion (39%) of Pd clusters on the alumina carrier enables lower production of ammonium ions, the concentration of which was found below 0.5 mg/L for initial nitrite content up to 70 mg/L. Both Pd-Cu bimetallic and Pd monometallic catalysts were found chemically resistant in the investigated range of pH values (4.5–12.4). In comparison to the previous scheme of integrated ion-exchange/catalytic process, in which the denitrification step was conducted in a single, “liquid-full” reactor unit packed with a Pd-Cu/γ-Al2O3 bimetallic catalyst, the production of ammonium ions was reduced by an order of magnitude.

Short interspersed elements (SINEs) make up a significant fraction of total DNA in mammalian genomes, providing a rich substrate for chromosomal rearrangements by SINE-SINE recombinations. Proliferation of mammalian SINEs is mediated primarily by long interspersed element 1 (L1) non-long terminal repeat retrotransposons that preferentially integrate at DNA sequence targets with an average length of approximately 15 bp and containing conserved endonucleolytic nicking signals at both ends. We report that sequence variations in the first of the two nicking signals, represented by a 5'-TT-AAAA consensus sequence, affect the position of the second signal thus leading to target site duplications (TSDs) of different lengths. The length distribution of TSDs appears to be affected also by L1-encoded enzyme variants because targets with the same 5' nicking site can be of different average lengths in different mammalian species. Taking this into account, we reanalyzed the second nicking site and found that it is larger and includes more conserved sites than previously appreciated, with a consensus of 5'-ANTNTN-AA. We also studied potential involvement of the nicking sites in stimulating recombinations between SINEs. We determined that SINEs retaining TSDs with perfect 5'-TT-AAAA nicking sites appear to be lost relatively rapidly from the human and rat genomes and less rapidly from dog. We speculate that the introduction of DNA breaks induced by recurring endonucleolytic attacks at these sites, combined with the ubiquitousness of SINEs, may significantly promote recombination between repetitive elements, leading to the observed losses. At the same time, new L1 subfamilies may be selected for "incompatibility" with preexisting targets. This provides a possible driving force for the continual emergence of new L1 subfamilies which, in turn, may affect selection of L1-dependent SINE subfamilies.

Temperature-programmed reduction (TPR), oxidation (TPO), and desorption (TPD) studies were performed on three copper-ceria mixed oxide samples having the same nominal composition, Cu0.15Ce0.85O(2-y), but prepared in three different ways: by co-precipitation, the sol-gel peroxide route, and the sol-gel citric acid route. The obtained results reveal that despite a drastic initial drop in specific surface area after consecutive redox cycles, the hydrogen consumption remains constant. This is because CuO is highly dispersed over the surface of CeO2 nanocrystallites and remains highly dispersed even after the agglomeration of CeO2 nanocrystallites in a denser secondary structure. The dispersed CuO is reduced to Cu(0) during the TPR, forming agglomerated metal particles on the surface of partially reduced CeO2. However, after subsequent temperature-programmed oxidation all the Cu(0) is oxidized back into CuO and redispersed over the CeO2 crystallites.

Peptidic lipopolysaccharide (LPS) antagonists are the subject of intensive research. We report an NMR and modeling study of LALF-14 (GCKPTFRRLKWKYKCG), a synthetic cyclized fragment of the limulus anti-LPS factor (LALF) comprising residues 36-47. In a mixture with LPS we observed the transferred NOE effect and derived the LPS-bound structure of LALF-14. Neither the free nor the LPS-bound peptide displays NOEs indicative of a beta-sheet-like structure that is adopted by the fragment in the full-size protein. However, docking calculations show that the former structure is not a prerequisite for binding of LALF-14 to LPS.

Catalytic liquid phase nitrate reduction was investigated at T=298 K and atmospheric pressure in an isothermal batch-recycle reactor in the presence of various Pd-Cu and Pd-Sn bimetallic catalysts supported on alumina spheres with particle diameter of 1.7 mm. It was discovered that Pd-Sn solids synthesized accordingly to various catalyst preparation methods, exhibit considerably lower activity for nitrate removal in comparison to Pd-Cu catalysts. Formation of undesired ammonium ions is favored over Pd-Sn/γ-Al2O3 catalysts prepared by impregnation and co-impregnation techniques. Acidity and textural properties of alumina supports as well as the presence of chloride ions in the catalyst–solution interface detrimentally influence catalytic performance in the process of liquid phase nitrate hydrogenation.

A simple theory of photon recycling (PR) was applied to the calculation of the photovoltage spectra of GaSb diodes. The PR is analyzed here as a two stage process with primary electron-hole pair photogeneration and diffusion followed by an optical transport of secondary carriers induced by emission and reabsorption of photons. The latter process is responsible for different behavior of diodes with and without the PR mechanism. Low losses of the secondary processes in comparison with losses in the primary one are assumed. The secondary processes can change the character of the photovoltage spectra significantly, enhancing the signal in the short wavelength region. The calculated photovoltage spectral response agrees well with the experiment giving the possibility to evaluate parameters of the material and of the measured diodes. The diffusion length obtained in this way characterizes only diffusion of electron-hole pairs and the influence of PR can be separated.

Dark current–voltage (I–V) characteristic measurement in the temperature range from −190 °C to 65 °C was carried out on GaSb p-n homojunctions prepared by low-pressure metalorganic vapor phase epitaxy. It was shown that the charge transport mechanism in these homojunctions is strongly affected by the growth rate of GaSb epitaxial layers. Samples prepared at higher growth rate (40 nm/min.) exhibit an anomalous low-temperature peak of tunneling current which can be explained by the presence of a narrow band of energies due to high concentration of native defects, probably GaSb antisites. The same defect levels are responsible for the generation–recombination current which dominates in these samples at higher temperatures. On the other hand, quite different behavior was found in the case of slowly grown (20 nm/min) samples. At sufficiently low temperatures, a current maximum near 50 mV of forward voltage points out a band-to-band tunneling as a prevailing transport mechanism. With increasing temperature, how...

Aim: To evaluate the levels of nitrite (NO–2) and nitrate (NO–3) ions and the incorporation of [3H]arachidonic acid (AA) into phospholipids of platelet membranes from coronary artery disease (CAD) patients with and without diabetes (NIDDM). Subjects and Methods: Eighteen CAD patients (group A), 18 CAD patients with NIDDM (group B), and 20 healthy controls (group C) without dyslipidemia, peripheral vascular disease and hypertension were included in the study. The groups were matched for age, sex and body mass index. The diagnosis of CAD was confirmed by coronary angiography. The nitric oxide end products (NOx), NO–2 plus NO–3 ions in platelet membranes, were determined using a spectrophotometric method based on the Griess reaction. The turnover of phospholipids was evaluated by incorporation of [3H]AA into platelet membrane phospholipids. Results: A significantly smaller amount of NOx ions was in the platelet membrane of groups A (40 ± 8 µmol/l) and B (29 ± 10 µmol/l) than C (57 ± 6 µmol/l), p < 0.001. Conversely a significantly greater amount of [3H]AA was incorporated into platelet phospholipids of group B patients (5,123 ± 1,637 dpm/mg) than groups A (3,159 ± 1,253 dpm/mg; p < 0.002) and C (1,621 ± 417 dpm/mg). An inverse correlation between [3H]AA incorporation and NOx levels was established: r = –0.76 (p < 0.05, n = 36) in CAD patients. Conclusions: Diabetes in CAD patients decreased the ability to produce platelet-derived NO and affects AA metabolism. This may result in higher platelet sensitivity to aggregating stimuli.

The performance of new FTIR-based monitoring technology to representatively determine reaction kinetics has been demonstrated on an example of homogeneously catalyzed liquid-phase sucrose hydrolysis to fructose and glucose. The reaction kinetics were investigated by using the ReactIRTM 1000 reaction analysis system, which enables determination of the component concentration from its characteristic FTIR spectrum. During the sucrose inversion, the ReactIRTM 1000 instrument connected to a computer controlled standard glass batch reactor provided the required operating conditions and information about the component concentration in real-time. We have studied the influence of hydrogen ion concentration, temperature and initial concentration of sucrose on the sucrose disappearance rate. It was found out that the inversion of sucrose is an irreversible reaction, which is not affected by the formation of fructose and glucose in the liquid-phase. Then, the parameters of the kinetic model (i.e., reaction rate constant and activation energy) were calculated. A comparison of the model output and the measured data showed that the kinetics of the sucrose inversion could be well described by means of the pseudo first-order kinetic model. Finally, the method of determining the kinetic model by FTIR spectroscopy was verified by comparing the results obtained in the batch reactor with the results obtained in the continuously stirred tank reactor.

Three different catalysts, namely Pt/γ-Al 2 O 3 , Au/α-Fe 2 O 3 and CuO-CeO 2 were prepared (by wet impregnation, coprecipitation and a sol-gel method, respectively) and their catalytic performance for the selective oxidation of carbon monoxide in the presence of excess hydrogen was evaluated and compared. The effects of the presence of CO 2 and H 2 O in the reactant feed on the activity and selectivity of these catalysts, as well as their stability under realistic reaction conditions were also investigated. Regardless of whether CO 2 or both CO 2 and H 2 O are present in the reactant feed, the Au/α-Fe 2 O 3 catalyst is superior to the other two for the selective CO oxidation at relatively low reaction temperatures (

Despite their enormous diversity and abundance, all currently known eukaryotic DNA transposons belong to only 15 superfamilies. Here, we report two new superfamilies of DNA transposons, named Sola and Zator. Sola transposons encode DDD-transposases (transposase, TPase) and are flanked by 4-bp target site duplications (TSD). Elements from the Sola superfamily are distributed in a variety of species including bacteria, protists, plants, and metazoans. They can be divided into three distinct groups of elements named Sola1, Sola2, and Sola3. The elements from each group have extremely low sequence identity to each other, different termini, and different target site preferences. However, all three groups belong to a single superfamily based on significant PSI-Blast identities between their TPases. The DDD TPase sequences encoded by Sola transposons are not similar to any known TPases. The second superfamily named Zator is characterized by 3-bp TSD. The Zator superfamily is relatively rare in eukaryotic species, and it evolved from a bacterial transposon encoding a TPase belonging to the "transposase 36" family (Pfam07592). These transposons are named TP36 elements (abbreviated from transposase 36).

Bimetallic γ-alumina-supported Pd–Cu catalysts with different Pd:Cu atomic ratios (2:1, 1:1, 1:2) and different total metal loadings (Pd+Cu: 6.1, 1.3, 0.65 wt.% at constant Pd:Cu=2:1) were prepared by pore volume successive impregnation technique. The materials were characterized by means of X-ray powder diffraction (XRD), extended X-ray absorption fine structure (EXAFS) spectroscopy, chemisorption of hydrogen, transmission electron microscopy (TEM) and energy-dispersive spectroscopy (EDX). TEM/EDX, H 2 chemisorption, and EXAFS results gave strong evidence that particles of nearly spherical shape, dispersed on supporting γ-alumina crystallites, are bimetallic. Comparison with Pd/γ-alumina prepared under identical conditions clearly suggests that the addition of copper decreases the amount of palladium atoms that chemisorb hydrogen. The H 2 chemisorption and EXAFS data indicated a dilution effect of Pd ensembles by copper atoms. It was found that both surface composition and bulk structure of the bimetallic particles varied with the Pd:Cu atomic ratio, while the size of particles did not change significantly. On the other hand, the Pd–Pd and Pd–Cu coordination values demonstrated that higher total metal loading at a constant Pd:Cu atomic ratio resulted in the formation of larger bimetallic particles. The highest H 2 chemisorption ability and the smallest bimetallic nanoparticles with nonuniform distribution of Pd and Cu were observed for Pd–Cu catalyst (Pd:Cu=2:1) previously reported, that exhibited the highest selectivity in a liquid-phase nitrate reduction.

A nitrate removal process that drastically reduces salt consumption and waste discharge has been developed on a bench scale. Nitrate is removed by chloride ion exchange, and the strong-base anion resin is completely regenerated at mild reaction conditions (i.e., ambient temperature, atmospheric pressure) in a closed circuit containing a single-flow fixed-bed reactor packed with a Pd–Cu/γ-Al 2 O 3 catalyst. The combined treatment system avoids direct contact between the denitrification reactor and the water to be treated, and minimizes operational problems associated with each separate technique. No dissolution of Pd and Cu metallic-phases was observed at the given operating conditions.

A nitrate removal process that drastically reduces salt consumption and waste discharge has been developed on a bench scale. Nitrate is removed by chloride ion-exchange, and the strong-base anion resin is completely regenerated at mild reaction conditions (i.e., ambient temperature, atmospheric pressure) in a closed circuit containing a single-flow fixed-bed reactor packed with a Pd-Cu/γ-Al 2 O 3 catalyst. The combined treatment system avoids direct contact between the denitrification reactor and the water to be treated, and minimizes operational problems associated with each separate technique. No dissolution of Pd and Cu metallic phases was observed at the given operating conditions.

Alumina-supported palladium-copper catalysts, which promote liquid-phase nitrate reduction, have been prepared according to different impregnation sequences of γ-Al 2 O 3 support and characterized by X-ray photoelectron spectroscopy (XPS), X-ray induced Auger electron spectroscopy (XAES) and temperature-programmed reduction (TPR). Analysis of Pd XPS/XAES spectra reveals that palladium is present on the γ-alumina support in the metallic form. Copper is reduced at lower temperatures in the presence of palladium particles compared to the CuO/γ-Al 2 O 3 sample. Due to the low copper content in catalysts ( σ Cu ≈10 14 atoms cm −2 ), the XPS/XEAS spectral features of reduced copper species are quite different from those of bulk copper. As shown by TPR and XPS/XAES data, formation of highly dispersed Pd-Cu bimetallic clusters is suggested. It was discovered by means of TPR analysis that the catalyst preparation in which the γ-alumina support is impregnated first by copper salt, results in higher formation of the Pd-Cu alloy.

A series of mixed oxide CuO–CeO2 catalysts were prepared by coprecipitation and tested for the selective oxidation of carbon monoxide in the presence of excess hydrogen. These catalysts were found to be very active and exceptionally selective for this reaction and exhibited a good resistance towards CO2 and H2O. The catalytic performance of these non-noble metal containing catalysts is compared with that of other selective CO oxidation catalysts reported in literature.

A method is described for the production of recombinant isotopically enriched peptides in E. coli. Peptides are produced in high yield as fusion proteins with ketosteroid isomerase which form insoluble inclusion bodies. This insoluble form allows easy purification, stabilizes the peptide against degradation and prevents bactericidal activity of the peptide. Cyanogen bromide cleavage released peptide which was conjugated with alkylamines to form lipopeptide. An important advantage of this system is that it allows production of peptides that are toxic to bacteria, which we have demonstrated on a dodecapeptide based on residues 21-31 of human bactericidal protein lactoferrin.

Liquid-phase hydrogenation using a solid Pd–Cu bimetallic catalyst offers a promising technique for the removal of nitrates from contaminated drinking water. In this study, catalytic nitrate reduction was investigated in isothermal fixed-bed reactors at T = 298 K and atmospheric pressure. Experiments carried out in a bubble-column fixed-bed reactor in the presence of distilled water as a reaction medium, demonstrate that nitrates can be efficiently removed from the liquid-phase, and that the maximum contaminant level for ammonium ions in drinking water is not exceeded. The measured nitrate conversions are considerably influenced by the variation of volumetric flow rate of either the gas- or liquid-phase. The order of magnitude analysis of apparent rate constant and mass transfer coefficients confirms that the observed reaction rate is governed by the mass transfer of hydrogen from the gas- into the bulk liquid-phase. Due to shorter mean residence times, lower nitrate conversions are measured in a trickle-bed reactor. At the given reaction conditions, catalyst particles were directly exposed to the gas-phase in this reactor system, which drastically enhanced ammonia production. When drinking water is used as a reaction medium instead of distilled water, the nitrate disappearance rate as well as reaction selectivity decrease appreciably, which is attributed to the presence of dissolved ionic species. Additionally, traces of nitrites were detected in the reactor effluent.

Ce1−xCuxO2−δcatalysts with 0.05

Synthesis of proteases as inactive zymogens is a very important mechanism for the regulation of their activity. For lysosomal proteases proteolytic cleavage of the propeptide is triggered by the acidic pH. By using fluorescence, circular dichroism, and NMR spectroscopy, we show that upon decreasing the pH from 6.5 to 3 the propeptide of cathepsin L loses most of the tertiary structure, but almost none of the secondary structure is lost. Another partially structured intermediate, prone to aggregation, was identified between pH 6.5 and 4. The conformation, populated below pH 4, where the activation of cathepsin L occurs, is not completely unfolded and has the properties of molten globule, including characteristic binding of the 1-anilinonaphthalene-8-sulfonic acid. This pH unfolding of the propeptide parallels a decrease of its affinity for cathepsin L and suggests the mechanism for the acidic zymogen activation. Addition of anionic polysaccharides that activate cathepsin L already at pH 5.5 unfolds the tertiary structure of the propeptide at this pH. Propeptide of human cathepsin L which is able to fold independently represents an evolutionary intermediate in the emergence of novel inhibitors originating from the enzyme proregions.

We have measured 1D and 2D 1 H and 13 C NMR spectra of selected Slovenian wines. Partial assignment of 1 H and 13 C resonances of alanine, valine, leucine, isoleucine, proline, threonine, ethanol, glycerol, butyleneglycol, and of acetic, tartaric, lactic, succinic, and malic acids in the wine samples was carried out by the combination of homo- and heteronuclear experiments COSY, HSQC and HMBC with known spectra of individual compounds. The spectra of wines of different variety, vintage and geographical areas differ mainly in the intensity of particular signals but also in the appearance of some signals which offers the possibility to follow the variability in their chemical composition on the ground of 1 H and 13 C signals.