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In this paper, the structure of newly developed modified aluminide coatings is characterized. The platinum and palladium coatings were obtained by an electroplating process. The Pt and Pd electroplated samples were aluminized and also modified by zirconium doping during the CVD (Chemical Vapour Deposition) low-activity process. Aluminide coatings were deposited using industrial CVD system. In the paper, the process parameters are described as well as the results of the microstructural analysis. The chemical and microstructure analysis was conducted using electron microscopes equipped with an energy dispersive spectrometer attachment. The phase composition analysis was performed using an X-ray diffractometer and showed that the aluminide coatings (Pt-Zr and Pd-Zr modified) obtained by CVD low-activity aluminizing comprised ß-NiAl phase grains enriched in platinum (max. approx. 16 at.% of Pt) or palladium (max. approx. 21 at.% of Pd). The coatings consisted of two or three zones. The first outer zone was a single phase - (Ni,Pt/Pd)Al type. The aluminium-content of the outer zone of the platinum modified aluminide coating was approx. 45 at.%, while aluminiumcontent in the outer zone of the palladium modified aluminide coatings was approx. 52 at.%. The results showed that the total thickness of aluminide coatings was an average of about 50 µm while the average thickness of the outer ß-NiAl zone was about 35 µm. These types of aluminide coating are applied to the thermal barrier coatings with a ceramic outer layer produced by EB-PVD (electron beam physical vapour deposition) or hybrid LPPS PS-PVD (Low-Pressure Plasma PS-PVD) methods. [ABSTRACT FROM AUTHOR]

Thermal barrier coatings (TBCs) are widely used for protection of gas turbine parts from high temperature and corrosion. In the present study, the new concept of TBCs with three-element-modified aluminide coatings was presented. In the first stage, the Pt and Pd were electroplated on MAR M247 nickel superalloy. In the next stage, the low-activity CVD aluminizing process with Zr or Hf doping was conducted. The ceramic layer containing yttria-stabilized zirconia was obtained by the plasma spray physical vapour deposition (PS-PVD) method. The microscopic examination showed the formation of aluminide coating containing up to 5 at% of Pt and 10 at% of Pd in (Ni, Pt, Pd)Al solid solution. The small concentration of Hf and Zr in diffusion zone of aluminide bond coat was noted as well. The outer ceramic layer was characterized by columnar structure typically formed during the PS-PVD process. The obtained results showed that the new concept of TBCs formed using new processes might be an attractive alternative to conventional coatings produced using the expensive electron beam physical vapour deposition (EB-PVD) method.

The response of the final instar larvae of G. mellonella to topical application of the non-steroidal ecdysone mimic, RH 5849, was age-related as well as dose-dependent. In young final instar larvae, moderate doses of RH 5849 induced perfect supernumerary larval moults, but doses equal to and higher than 8.5 μg per larva caused premature formation of larval cuticle and were lethal. Application of RH 5849 significantly increased allatotropic activity of the brain, and also activated synthesis of juvenile hormone (JH) by the corpora cardiaca/corpora allata complex. Simultaneous application of RH 5849 and FMev, a potent inhibitor of JH synthesis, to young final instar larvae lowered the incidence of perfect supernumerary larval moults. We conclude that the effect of RH 5849 on the developmental programme in G. mellonella is mediated by the corpora allata. [ABSTRACT FROM AUTHOR]

New refining technology of soda-calcium-silicon glass surfaces with inorganic compounds nano-molecules has been presented in the study. In order to determine modification of the glass surface SEM observation and EDX analysis have been carried out. The UV-VIS, photo-elasticity and ellipsometry examinations were carried out on glass samples. The results of investigations that have been conducted show that refining process of the glass surface by use of nanopowder inorganic compounds deposited electrostatically on glass surface provides forming of very thin (about 50 nm) surface layers [1]. This method of surface modification improves physical and chemical glass properties. In this paper results of microhardness test of refined glass were also presented.

Time course analysis of juvenile hormone degradation in the brain and the corpora cardiaca-corpora allata complex shows that during the first two days of the last larval instar the juvenile hormone degradation is very low. Starting from the third day up to the seventh day a continuous increase of esterase activity is observed. [ABSTRACT FROM AUTHOR]

The brain allatotropic hormone (ATTH) is released in Galleria mellonella from the Median neurosecretory cells located in the pars intercerebralis. These cells show the ability to elicit supernumerary larval molts upon implantation into sensitive host larvae, and the ability to in vitro stimulate the juvenile hormone synthesis in corpora cardiaca-corpora allata glands of G. mellonella. [ABSTRACT FROM AUTHOR]

The catalytic properties of a series of novel chromium(iii) salophen complexes having different pyridinium chloride units (pyridinium, 2,6-dimethylpyridinium or 4-(dimethylamino)pyridinium ones) have been studied in the reaction of carbon dioxide cycloaddition to phenyl glycidyl ether. The examined complexes were found to be capable of catalyzing cycloaddition under relatively mild reaction conditions without any additional nucleophilic co-catalyst. However, their catalytic activity depended strongly on the structure and number of pyridinium salt units in the ligand molecule. The complex with a single unit of 4-(dimethylamino)pyridinium chloride turned out to be the most active among the examined ones. A TOF of up to 1480 h -1 was obtained in the presence of this catalyst under the following conditions: 120 °C, 2 h, 6 bar, 0.05 mol% (74% epoxide conversion, and >99% selectivity). The most active complex has also been examined as a catalyst in the reactions of CO 2 with a series of ten other terminal epoxides. High catalytic activity (TOF = 220-5045 h -1 ) was observed in most cases, except for the reaction of CO 2 with allyl glycidyl ether., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The effect of ligand structure on the catalytic activity of amine-bis(phenolate) chromium(III) complexes in the ring-opening copolymerization of phthalic anhydride and a series epoxides was studied. Eight complexes differing in the donor-pendant group (R 1 ) and substituents (R 2 ) in phenolate units were examined as catalysts of the model reaction between phthalic anhydride and cyclohexane oxide in toluene. They were used individually or as a part of the binary catalytic systems with nucleophilic co-catalysts. The co-catalyst was selected from the following organic bases: PPh 3 , DMAP, 1-butylimidazole, or DBU. The binary catalytic systems turned out to be more active than the complexes used individually, and DMAP proved to be the best choice as a co-catalyst. When the molar ratio of [PA]:[epoxide]:[Cr]:[DMAP] = 250:250:1:1 was applied, the most active complex (R 1 -X = CH 2 NMe 2 , R 2 = F) allowed to copolymerize phthalic anhydride with differently substituted epoxides (cyclohexene oxide, 4-vinylcyclohexene oxide, styrene oxide, phenyl glycidyl ether, propylene oxide, butylene oxide, and epichlorohydrin) within 240 min at 110 °C. The resulting polyesters were characterized by M n up to 20.6 kg mol -1 and narrow dispersity, and they did not contain polyether units.

Objectives: The aim of the present study is to assess differences in body composition between female participants in the study group who suffer from PCOS versus a healthy control group., Material and Methods: The study included 85, 14-22-year-old, female participants. Participants belonged to one of two groups. Thirty seven participants with a diagnosis of PCOS were in the clinical group, and 48 participants were in the healthy control group with no prior diagnosis of PCOS., Results: A statistically significant difference between groups was found in their answer regarding diet. A correlation was found between the body fat index and the use of dieting among participants; participants with a lower body fat index (in kilograms) were less likely to be on a diet., Conclusions: The young female participants with PCOS were shown to have similar body composition to age-matched healthy controls. However, the clinical group with PCOS reported more frequent use of dieting, with less use of exercise.

Background: The study investigated the relationship between dietary intake of polyphenols and inflammatory markers: CRP, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), medium platelet volume/lymphocyte ratio (MPVRL), in newly-diagnosed breast cancer patients., Objectives: The aim of this work was to verify whether diet rich in plant polyphenols affects inflammatory markers in breast cancer patients., Materials and Methods: 78 patients (55.3±14.5 years) treated surgically for breast cancer were studied. A modified FFQ and authorial worksheet based on the Phenol Explorer database was used to measure the amount of plant polyphenols in a diet. Basing on the median of polyphenols intake (1780 mg/day), the group was divided into two subgroups: low- and high- dietary intake of polyphenols (LDIP and HDIP, respectively). Plasma CRP level was measured and NLR, PLR and MPVLR were calculated using results from peripheral blood morphology., Results: LDIP was associated with significantly higher CRP (elevated in 34.5% LDIP patients vs. 8.3% HDIP, p<0.003), NLR (elevated in 46.2% LDIP patients vs. 25.6% HDIP, p<0.006) and PLR level (elevated in 25.6% LDIP patients vs. 12.8% HDIP, p<0.03). MPVLR was not significantly different between both the subgroups., Conclusion: High dietary intake of polyphenols remarkably reduced process of inflammation in breast cancer patients, which has important clinical implications. The study demonstrated also an usefulness of simple, cheap and commonly available biomarkers for monitoring anti-inflammatory effects of diet.

Twelve high schools in Japan (of which six are in Fukushima Prefecture), four in France, eight in Poland and two in Belarus cooperated in the measurement and comparison of individual external doses in 2014. In total 216 high-school students and teachers participated in the study. Each participant wore an electronic personal dosimeter 'D-shuttle' for two weeks, and kept a journal of his/her whereabouts and activities. The distributions of annual external doses estimated for each region overlap with each other, demonstrating that the personal external individual doses in locations where residence is currently allowed in Fukushima Prefecture and in Belarus are well within the range of estimated annual doses due to the terrestrial background radiation level of other regions/countries.

Objective: Interstitial brachytherapy is becoming an accepted treatment option for lung cancer patients for whom surgery poses a high risk. Robotic surgery has the potential to deliver brachytherapy seeds into tumors while keeping surgeons at a safe distance from the radioactive source. Our aim was to compare the accuracy, number of attempts, and time needed to place seeds next to a target when using a manual technique, video-assisted thoracoscopic surgery (VATS), and the ZEUS robot for minimally invasive surgery (MIS)., Methods: A brachytherapy seed injector was developed and attached to one of the ZEUS robotic arms. Four subjects each inserted inactive dummy brachytherapy seeds into clear agar-gelatin cubes containing a 1.6-mm stainless steel ball target. Two orthogonal radiographs were taken of each agar cube, and the corresponding distances were measured in triplicate using ImageJ processing software. The mean distance between the center of each seed and the corresponding target was calculated using the Pythagorean theorem. Comparisons were made using analysis of variance, t-tests, and Kruskal-Wallis tests, as appropriate., Results: A total of 384 tests (128 for each technique) were performed. The median accuracies for the manual technique, VATS, and ZEUS were 1.8 mm (range: 0.9-6.7 mm), 2.4 mm (range: 1.0-11.3 mm), and 3.6 mm (range: 1.3-16.7 mm), respectively (p < 0.01). The median numbers of attempts for the manual technique, VATS, and ZEUS were 1 (range: 1-5), 4 (range: 1-14), and 3 (range: 1-20), respectively (p < 0.01). The median times for the manual technique, VATS, and ZEUS were 3.0 s (range: 1-43 s), 86.5 s (range: 6-372 s), and 64.5 s (range: 5-356 s), respectively (p < 0.01)., Conclusions: The manual technique is the most accurate, least traumatic, and fastest method of inserting seeds into tumors. The ZEUS robotic platform was able to place seeds beside a target within a clinically acceptable distance, with an acceptable amount of trauma and time required. It achieved results equal to or better than those obtained with VATS.

Estrogens exert a variety of modulatory effects on the structure and function of the nervous system. In particular, 17 beta-estradiol was found to affect GABAergic inhibition in adult animals but its action on GABAergic currents during development has not been elucidated. In the present study, we investigated the effect of 17 beta-estradiol on hippocampal neurons developing in vitro. In this model, mIPSC kinetics showed acceleration with age along with increased alpha1 subunit expression, similarly as in vivo. Long-term treatment with 17 beta-estradiol increased mIPSC amplitudes in neurons cultured for 6-8 and 9-11DIV and prolonged the mIPSC decaying phase only in the 9-11DIV group. The time needed for the onset of 17 beta-estradiol effect on mIPSC amplitude was approximately 48 h. In the period of 9-11DIV, treatment with 17 beta-estradiol strongly reduced the tonic conductance activated by low GABA concentrations. The effects of 17 beta-estradiol on mIPSCs and tonic conductance were not correlated with any change in expression of considered GABAAR subunits (alpha1-3, alpha5-6, gamma2) while alpha4 and delta subunits were at the detection limit. In conclusion, we provide evidence that 17 beta-estradiol differentially affects the phasic and tonic components of GABAergic currents in neurons developing in vitro.

Recently, we have reported that extracellular protons allosterically modulated neuronal GABA(A) receptors [Mozrzymas, J.W., Zarnowska, E.D., Pytel, M., Mercik, K., 2003a. Modulation of GABA(A) receptors by hydrogen ions reveals synaptic GABA transient and a crucial role of desensitiztion process. Journal of Neuroscience 23, 7981-7992]. However, GABAARs in neurons are heterogeneous and the effect of hydrogen ions depends on the receptor subtype. In particular, gamma2 subunit sets the receptor sensibility to several modulators including protons. However, the mechanisms whereby protons modulate gamma2-containing and gamma2-free GABAARs have not been fully elucidated. To this end, current responses to ultrafast GABA applications were recorded for alpha1beta2gamma2 and alpha1beta2 receptors at different pH values. For both receptor types, increase in pH induced a decrease in amplitudes of currents elicited by saturating [GABA] but this effect was stronger for alpha1beta2 receptors. In the case of alpha1beta2gamma2 receptors, protons strongly affected the current time course due to a down regulation of binding and desensitization rates. This effect was qualitatively similar to that described in neurons. Protons strongly influenced the amplitude of alpha1beta2 receptor-mediated currents but the effect on their kinetics was weak suggesting a predominant direct non-competitive inhibition with a minor allosteric modulation. In conclusion, we provide evidence that extracellular protons strongly affect GABAA receptors and that, depending on the presence of the gamma2 subunit, the modulatory mechanisms show profound quantitative and qualitative differences.

Cyclodextrins (CDs) are nanostructures widely applied in biotechnology and chemistry. Owing to partially hydrophobic character, CDs interact with biological membranes. While the mechanisms of CDs interactions with lipids were widely studied, their effects on proteins are less understood. In the present study we investigated the effects of beta cyclodextrin (betaCD) on GABA(A) receptor (GABA(A)R) gating. To reliably resolve the kinetics of conformational transitions, currents were elicited by ultrafast gamma-aminobutyric acid (GABA) applications to outside-out patches from rat cultured hippocampal neurons. betaCD increased the amplitude of responses to saturating GABA concentration ([GABA]) in a dose-dependent manner and this effect was accompanied by profound alterations in the current kinetics. Current deactivation was slowed down by betaCD but this effect was biphasic with a maximum at around 0.5 mM betaCD. While the fast deactivation time constant was monotonically slowed down within considered betaCD concentration range, the slow component first increased and then, at millimolar betaCD concentration, decreased. The rate and extent of desensitization was decreased by betaCD in a dose-dependent manner. The analysis of current responses to nonsaturating [GABA] indicated that betaCD affected the GABA(A)R agonist binding site by slowing down the unbinding rate. Modulation of GABA(A)R desensitization and binding showed different concentration-dependence suggesting different modualtory sites with higher affinity of the latter one. All the betaCD effects were fully reversible indicating that cholesterol uptake into betaCD was not the primary mechanism. We conclude that betaCD is a strong modulator of GABA(A)R conformational transitions.

The kinetics of GABAergic currents in neurons is known to be modulated by the membrane voltage but the underlying mechanisms have not been fully explored. In particular, the impact of membrane potential on the GABA(A) receptor gating has not been elucidated. In the present study, the effect of membrane voltage on current responses elicited by ultrafast GABA applications was studied in cultured hippocampal neurons. The current to voltage relationship (I-V) for responses to saturating [GABA] (10 mM) showed an inward rectification (slope conductance at positive voltages was 0.62 +/- 0.05 of that at negative potentials). On the contrary, I-V for currents evoked by low [GABA] (1 microM) showed an outward rectification. The onset of currents elicited by saturating [GABA] was significantly accelerated at positive potentials. Analysis of currents evoked by prolonged applications of saturating [GABA] revealed that positive voltages significantly increased the rate and extent of desensitization. The onsets of current responses to non-saturating [GABA] were significantly accelerated at positive voltages indicating an enhancement of the binding rate. However, at low [GABA] at which the onset rate is expected to approach an asymptote set by opening/closing and unbinding rates, no significant modification of current onset by voltage was observed. Quantitative analysis based on model simulations indicated that the major effect of membrane depolarization was to increase the rates of binding, desensitization and of opening as well as to slightly reduce the rate of exit from desensitization. In conclusion, we provide evidence that membrane voltage affects the GABA(A) receptor microscopic gating.

Recent analysis of current responses to exogenous GABA applications recorded from excised patches indicated that membrane voltage affected the GABAA receptor gating mainly by altering desensitization and binding [M. Pytel, K. Mercik, J.W. Mozrzymas, Membrane voltage modulates the GABAA receptor gating in cultured rat hippocampal neurons, Neuropharmacology, in press]. In order investigate the impact of such voltage effect on GABAA receptors in conditions of synaptic transmission, mIPSCs and current responses to rapid GABA applications were recorded from the same culture of rat hippocampal neurons. We found that I-V relationship for mIPSCs amplitudes showed a clear outward rectification while for current responses an inward rectification was seen, except for very low GABA concentrations. A clear shift in amplitude cumulative distributions indicated that outward rectification resulted from the voltage effect on the majority of mIPSCs. Moreover, the decaying phase of mIPSCs was clearly slowed down at positive voltages and this effect was represented by a shift in cumulative distributions of weighted decaying time constants. In contrast, deactivation of current responses was only slightly affected by membrane depolarization. These data indicate that the mechanisms whereby the membrane voltage modulates synaptic and extrasynaptic receptors are qualitatively different but the mechanism underlying this difference is not clear.

Recent studies have indicated that changes in extracellular pH and in membrane voltage affect the gamma-amino-n-butyric acid type A receptor gating mainly by altering desensitization and binding. To test whether the effects of membrane potential and pH are additive, their combined actions were investigated. By analyzing the current responses to rapid gamma-amino-n-butyric acid applications, we found that the current to voltage relationship was close to linear at acid pH but the increasing pH induced an inward rectification. Desensitization was enhanced at depolarizing potentials, but this strongly depended on pH, being weak at acidic and strong at basic pH values. A similar trend was observed for the onset rate of responses to saturating gamma-amino-n-butyric acid concentration. These data provide evidence that the voltage sensitivity of GABAA receptors depends on extracellular pH.

Neuronal gamma-aminobutyric acid (GABA)(A) receptors are extremely heterogeneous and therefore GABAergic currents represent responses of unknown mixture of receptor subtypes. Expression of recombinant receptors in foreign cells allows to investigate a defined receptor subtype but its properties can be altered due to, e.g., differences in the endogenous modulators. In the present study the alpha1beta2gamma2 receptors were expressed in HEK293 and QT-6 cells and current responses to ultrafast GABA applications were recorded. Rise time and rapid deactivation component were faster in responses recorded from QT-6 cells. Moreover, in QT-6 cells desensitization was faster and more profound. Recovery in the paired pulse experiments was faster in HEK293 cells. In conclusion, we provide evidence that recombinant receptors may show functional differences when expressed in different cells.

Protons are the most ubiquitous and very potent modulators of the biological systems. Hydrogen ions are known to modulate GABA(A) receptors (GABA(A)Rs), but the mechanism whereby these ions affect IPSCs and the gating of GABA(A)Rs is not clear. In the present study we examined the effect of protons on miniature IPSCs (mIPSCs) and found that hydrogen ions strongly affected both their amplitude and time course. To explore the underlying mechanisms with resolution adequate to the time scale of synaptic transmission, we recorded current responses to ultrafast GABA applications at various pH. These experiments revealed that the major effect of protons on GABA(A)R gating is a strong enhancement of desensitization and binding rates at increasing pH. This analysis also indicated that desensitization rate is the fastest ligand-independent transition in the GABA(A)R gating scheme. Although proton effects on the time course of mIPSCs and current responses to saturating [GABA] were similar, the pH dependencies of amplitudes were almost opposite. Our quantitative analysis, based on model simulations, indicated that this difference resulted from a much shorter receptor exposure to agonist in the case of mIPSCs. Modeling of IPSCs as current responses to brief exponentially decaying GABA applications was sufficient to reproduce correctly the pH dependence of mIPSCs, and optimal fit was obtained for peak [GABA] of 1.5-3 mm and a clearance time constant of 0.075-0.125 msec. Our analysis indicates that, for these parameters of GABA transient, in control conditions (pH 7.2) mIPSCs are not saturated.

Synaptic transmission plays a crucial role in signal transduction in the adult central nervous system. It is known that synaptic transmission can be modulated by physiological and pathological processes and a number of factors including metal ions, pH, drugs, etc. The patch-clamp technique allows to measure postsynaptic currents, but the mechanism of these currents modulation remains unclear. The estimated value of neurotransmitter transient indicates that this time course is very short and the activation of postsynaptic receptors is extremely non-equilibrient. The ultrafast perfusion system makes it possible to mimic synaptic conditions and, additionally, the agonist concentration can be controlled, which is very important for pharmacokinetic studies. In the present paper, examples of pharmacological modulation of mIPSC kinetics and currents evoked by ultrafast agonist application are presented.

36 patients with primary gastric non-Hodgkin's lymphoma (PGL) (stage Ie and IIe) were treated at the Comprehensive Cancer Center of Aviano (PN) Italy. The median follow-up time of the patients was 59 months (range 10 to 117). The pre-operative diagnosis of PGL was established by using endoscopy in 70% of the patients. There was understaging in non-invasive methods of diagnosis in comparison to laparotomy. Prognostic factors such as: stage, grade according to the Working Formulation, size, depth of penetration of the gastric wall and resectability of the tumor, were taken into consideration in the treatment plan. This consisted of surgical resection of the gastric lymphoma where feasible and according to the bad prognostic factors escalating adjuvant treatment was included: group I (n = 6) patients were treated only by surgery (S), II (n = 8) by S+radiotherapy (RT) (n = 5) or S+chemotherapy (CT) (n = 3), III (n = 17) by S+RT+CT and IV (n = 5) by non-resectable S+RT+CT. There were no statistically significant differences in the survival rate, calculated by Kaplan-Meier method, between the first three groups of patients. Only stage of disease (P = 0.048) and resectability of the lesion (P = 0.003) had a significant influence on survival. There were no serious complications observed in either S, RT or CT treatment. The estimated 5-year survival rate after management was 100%, 75% and 88%, respectively for stage Ie (n = 21), stage IIe (n = 15) and all together.