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71.
Snejana Bakardjieva Jakub Mares Radek Fajgar Victor Y. Zenou Michaela Maleckova Efthalia Chatzisymeon Hana Bibova Jaromir Jirkovsky 《RSC advances》2019,9(40):22988
Titanium dioxide modified with 3 wt% La was prepared via a green freeze-casting method, and its photocatalytic activity was tested in terms of its ability to degrade 4-chlorophenol (4-CP) and remove total organic carbon (TOC). Under annealing conditions, the freeze-cast precursor was transformed into an La-modified anatase with a well-defined 2D TiO2 nanosheet morphology. Rietveld refinement of the X-ray diffraction patterns confirmed the substitutional nature of the La cation that induced local structural variations and involved subtle ion displacement in the TiO2 lattice due to the ionic size effect. Despite nearly identical tetragonal structures, replacement of Ti with La alters the photocatalytic activity through a reduction in band gap energies and an increase in charge carrier mobility. Material annealed at 650 °C exhibited the highest photocatalytic performance and achieved efficient TOC removal. Upon annealing at 800 °C, nanoscale lanthanum-enriched regions were generated due to the diffusive migration of La cations and phase transition from anatase to rutile. The La3+ cation, acting as a structural promoter, supported 2D TiO2 growth with well controlled crystallite size, surface area and porosity. La3+ could be regarded as a potential electronic promoter that can reduce the band gap of 2D TiO2 nanosheets and can provide a signature of the electron transfer and carrier charge separation. Both methods, kinetics of degradation of 4-CP and TOC, provided similar results, revealing that the photocatalytic activity under UV light irradiation increased in the order 950C < 500 °C < 800 °C < 650 °C < TiO2-P25.Titanium dioxide modified with 3 wt% La was prepared via a green freeze-casting method, and its photocatalytic activity was tested in terms of its ability to degrade 4-chlorophenol (4-CP) and remove total organic carbon (TOC). 相似文献
72.
Pituitary adenylate cyclase activating polypeptide (PACAP) is a multifunctional neuropeptide expression of which has been found in various tumors of the brain and peripheral organs. Despite numerous studies, the exact role the peptide plays in the development and progression of tumors is not fully understood. In the present study, we investigated the effect of PACAP on human retinoblastoma Y79 cell viability. We found that both PACAP38 and PACAP6-38, a selective PAC1 receptor antagonist, did not affect Y79 cell viability at nanomolar concentrations, but when used at 1–5 μM potently reduced cell survival in a dose-dependent manner. PACAP27 and maxadilan, a high affinity agonist of PAC1 receptors, had negligible effects. Two membrane-penetrating analogs of PACAP38 inactive at PAC1/VPAC receptors, [Disc6]PACAP38 and FITC-Ahx-PACAP11-38, also decreased viability of Y79 cells, albeit with lower potency than PACAP38. The cytotoxic effect of PACAP38 was augmented by p38, MEK1/2, and JNK inhibitors, indicating that high concentrations of the peptide might decrease the activity of these kinases, leading to cell death. It is suggested that the cytotoxic activity of PACAP38 and PACAP6-38 against human retinoblastoma Y79 cell line may result from their interaction with target sites other than PAC1 and VPAC receptors, but this is yet unknown. 相似文献
73.
Jakub Rosik Bartosz Szostak Filip Machaj Andrzej Pawlik 《Annals of human genetics》2020,84(2):114-124
Diabetes mellitus (DM) is a heterogeneous group of disorders whose common trait is chronic hyperglycemia. Gestational diabetes mellitus (GDM) is one of the subtypes of DM that manifests during pregnancy. It is believed that 2%–5% of pregnancies worldwide are complicated with GDM, with the prevalence having significantly increased over the last decade. While the pathogenesis of the disease remains largely unknown, GDM is believed to be a result of interactions between genetic, epigenetic, and environmental factors. Linkage and association studies, including those that are genome-wide, have allowed us to identify complex genetic and epigenetic mechanisms that lead to the development of GDM. Multiple common variants in candidate genes such as potassium inwardly rectifying channel subfamily J, member 11 (KCNJ11), glucokinase (GCK), or hepatocyte nuclear factor 1α (HNF1A) have been found to increase the disease risk. In this review, we provide a detailed overview of the current knowledge concerning the influence of genetics and epigenetics on the development of GDM. 相似文献
74.
Jakub Trizuljak Wolfgang R. Sperr Lucie Nekvindová Hanneke O. Elberink Karoline V. Gleixner Aleksandra Gorska Magdalena Lange Karin Hartmann Anja Illerhaus Massimiliano Bonifacio Cecelia Perkins Chiara Elena Luca Malcovati Anna B. Fortina Khalid Shoumariyeh Mohamad Jawhar Roberta Zanotti Patrizia Bonadonna Francesca Caroppo Alexander Zink Massimo Triggiani Roberta Parente Nikolas von Bubnoff Akif S. Yavuz Hans Hägglund Mattias Mattsson Jens Panse Nadja Jäkel Alex Kilbertus Olivier Hermine Michel Arock David Fuchs Vito Sabato Knut Brockow Agnes Bretterklieber Marek Niedoszytko Björn van Anrooij Andreas Reiter Jason Gotlib Hanneke C. Kluin-Nelemans Jiri Mayer Michael Doubek Peter Valent 《Allergy》2020,75(8):1927-1938
75.
76.
Jií Svoboda Petr Boil Jakub Holzer Natlia Luptkov Milan Jarý Bohuslav Maek Petr Dym
ek 《Materials》2022,15(2)
Oxide-dispersion-strengthened (ODS) Fe-Al-Y2O3-based alloys (denoted as FeAlOY) containing 5 vol. % of nano-oxides have a potential to become top oxidation and creep-resistant alloys for applications at temperatures of 1100–1300 °C. Oxide dispersoids cause nearly perfect strengthening of grains; thus, grain boundaries with limited cohesive strength become the weak link in FeAlOY in this temperature range. One of the possibilities for significantly improving the strength of FeAlOY is alloying with appropriate elements and increasing the cohesive strength of grain boundaries. Nearly 20 metallic elements have been tested with the aim to increase cohesive strength in the frame of preliminary tests. A positive influence is revealed for Al, Cr, and Y, whereby the influence of Y is enormous (addition of 1% of metallic Y increases strength by a factor of 2), as it is presented in this paper. 相似文献
77.
Phonolite material has shown to be promising catalyst support for the deoxygenation of triglycerides. In this work, we continue with our previous research by synthesising and testing three acid-treated phonolite-supported Co-Mo, Ni-Mo and Ni-W catalysts for the hydrotreating of atmospheric gas oil and co-processing with rapeseed oil at industrial operating conditions (350–370 °C, WHSV 1–2 h−1, 5.5 MPa) in the continuous regime for more than 270 h. The phonolite-supported catalysts showed hydrotreating activity comparable with commercial catalysts, together with a complete conversion of triglycerides into n-alkanes. During co-processing, the Ni-promoted catalyst showed strong stability, with similar activity previous to the rapeseed oil addition. Our results enable us to evaluate the suitability of phonolite as catalyst support for the development of plausible alternatives to conventional hydrotreating catalysts for the co-processing of middle distillates with vegetable oils. 相似文献
78.
Beatrice L. Chinen Jakub Hyvl Daniel F. Brayton Matthew M. Riek Wesley Y. Yoshida Timothy W. Chapp Arnold L. Rheingold Matthew F. Cain 《RSC advances》2021,11(46):28602
In order to stabilize a 10–P–3 species with C2v symmetry and two lone pairs on the central phosphorus atom, a specialized ligand is required. Using an NCN pincer, previous efforts to enforce this planarized geometry at P resulted in the formation of a Cs-symmetric, 10π-electron benzazaphosphole that existed as a dynamic “bell-clapper” in solution. Here, OCO pincers 1 and 2 were synthesized, operating under the hypothesis that the more electron-withdrawing oxygen donors would better stabilize the 3-center, 4-electron O–P–O bond of the 10–P–3 target and the sp3-hybridized benzylic carbon atoms would prevent the formation of aromatic P-heterocycles. However, subjecting 1 to a metalation/phosphination/reduction sequence afforded cyclotriphosphane 3, resulting from trimerization of the P(i) center unbound by its oxygen donors. Pincer 2 featuring four benzylic CF3 groups was expected to strengthen the O–P–O bond of the target, but after metal–halogen exchange and quenching with PCl3, unexpected cyclization with loss of CH3Cl was observed to give monochlorinated 5. Treatment of 5 with (p-CH3)C6H4MgBr generated crystalline P-(p-Tol) derivative 6, which was characterized by NMR spectroscopy, elemental analysis, and X-ray crystallography. The complex 19F NMR spectra of 5 and 6 observed experimentally, were reproduced by simulations with MestreNova.Attempted synthesis of OCO-supported 10–P–3 species led to trimerization or cyclization. 相似文献
79.
Jakub Ka
mierski Piotr Miler Agnieszka Pawlak Hanna Jerczyska Karina Nowakowska Grzegorz Walkiewicz Katarzyna Wo
niak Micha Krejca Mirosaw Wilczyski 《Annals of medicine》2022,54(1):610
BackgroundThough risk factors of postoperative delirium are well described, its pathophysiology is still undiscovered. The primary objective of the current study is to assess whether increased pre- and postoperative myeloperoxidase (MPO) levels are associated with postoperative delirium in the population of cardiac surgery patients. The secondary objective is to evaluate the correlation between MPO levels and serum antioxidant capacity (AC).MethodsThe patients’ cognitive status was assessed one day preoperatively with the use of the Mini-Mental State Examination Test and the Clock Drawing Test. A diagnosis of major depressive disorder and anxiety disorders was established based on DSM-5 criteria. Blood samples for MPO and AC levels were collected both pre- and postoperatively. The Confusion Assessment Method for the Intensive Care Unit was used to screen for a diagnosis of delirium.ResultsDelirium occurred in 34% (61 of 177) of patients. Multivariable logistic regression analysis revealed that increased postoperative MPO concentration was independently associated with postoperative delirium development, and negatively correlated with lower baseline serum AC.ConclusionsCardiac surgery patients with less efficient antioxidative mechanisms experience a higher postoperative peak of serum MPO, which in turn may predispose to postoperative delirium development.
KEY MESSAGES
- MPO is a lysosomal enzyme with strong pro-oxidative and pro-inflammatory properties.
- Cardiac surgery patients who have increased concentration of postoperative MPO are at significantly higher risk of postoperative delirium development.
- This higher level of postoperative MPO is negatively correlated with baseline antioxidant capacity (AC).
- It can be hypothesized that individuals with decreased baseline AC experience a higher peak of MPO post-surgery due to less efficient antioxidative mechanisms, which in turn contributes to postoperative delirium development.
80.