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The random motion (the diffusion) of guest molecules in nanoporous host materials is key to their manifold technological applications and, simultaneously, a ubiquitous phenomenon in nature quite in general. Based on a specification of the different conditions under which molecular diffusion in nanoporous materials may occur and of the thus resulting relevant parameters, a survey of the various ways of the measurement of the determining parameters is given. Starting with a condensed introduction to the respective measuring principles, the survey notably includes a summary of the various parameters accessible by each individual technique, jointly with an overview of their strengths and weaknesses as well as of the respective ranges of observation. The presentation is complemented by basic relations of diffusion theory and molecular modeling in nanoporous materials, illustrating their significance for enhancing the informative value of each measuring technique and the added value attainable by their combination. By providing guidelines for the measurement and reporting of diffusion properties of chemical compounds in nanopores, the document aims to contribute to the clarification and standardization of the presentation, nomenclature, and methodology associated with the documentation of diffusion phenomena in nanoporous materials serving for catalytic, mass separation, and other relevant purposes. [ABSTRACT FROM AUTHOR]

Background/Objectives: Some specific anthraquinone derivatives (AQs) are known to be used widely as effective chemotherapeutic agents in the treatment of cancer. However, their fundamental shortcoming is the high rate of cardiotoxicity observed in treated patients, which is thought to be caused by the increase in production of reactive oxygen species (ROS) catalyzed by iron and copper. The development of improved AQs and other anticancer drugs with enhanced efficacy but reduced toxicity remains a high priority. The aim of this study was to evaluate the cytotoxic and ROS production effects of chelate iron and copper complexes of two novel AQs, namely 4-hydroxynaphto[2,3-h]cinnoline-7,12-dione (Q2) and 3-(hydroxymethyl)naphto[2,3-h]cinnoline-4,7,12(1H)-trione (Q3). Methods: The chelation ability of Q2 and Q3 was studied using NMR and UV–Vis spectroscopy. Cytotoxicity studies were carried out using the MTT assay. The influence of chelation on ROS production was studied using NMR spectroscopy in linoleic acid micelles. Results: It was found that only Q3 forms complexes with Fe(III) and Cu(II) ions, whereas Q2 does not demonstrate chelating properties. A cytotoxicity study revealed that Fe[Q3]3 significantly decreased the viability of lung cancer A549 cells, while Q3 and Cu[Q3]2 did not demonstrate cytotoxic properties in this cell line. Furthermore, the presence of Q3 lowered the rate of iron-induced lipid peroxidation in linoleic acid micelles. By contrast, Q2 did not influence the rate of lipid peroxidation, probably due to the absence of effective metal chelating ability. Conclusions: The high cytotoxic effects observed with the iron complex of Q3 against cancer cells in combination with a reduced rate of iron induced lipid peroxidation in the presence of Q3, make Q3 and its iron complex promising for further evaluation and use as chemotherapeutic agents in cancer. [ABSTRACT FROM AUTHOR]

Calciprotein particles (CPPs) are essential circulating scavengers of excessive Ca2+ and PO43− ions, representing a vehicle that removes them from the human body and precludes extraskeletal calcification. Having been internalised by endothelial cells (ECs), CPPs induce their dysfunction, which is accompanied by a remarkable molecular reconfiguration, although little is known about this process's extracellular signatures. Here, we applied ultra-high performance liquid chromatography-tandem mass spectrometry to perform a secretome-wide profiling of the cell culture supernatant from primary human coronary artery ECs (HCAECs) and internal thoracic artery ECs (HITAECs) treated with primary CPPs (CPP-P), secondary CPPs (CPP-S), magnesiprotein particles (MPPs), or Ca2+/Mg2+-free Dulbecco's phosphate-buffered saline (DPBS) for 24 h. Incubation with CPP-P/CPP-S significantly altered the profiles of secreted proteins, delineating physiological and pathological endothelial secretomes. Neither pathway enrichment analysis nor the interrogation of protein–protein interactions detected extracellular matrix- and basement membrane-related molecular terms in the protein datasets from CPP-P/CPP-S-treated ECs. Both proteomic profiling and enzyme-linked immunosorbent assay identified an increased level of protectin (CD59) and reduced levels of osteonectin (SPARC), perlecan (HSPG2), and fibronectin (FN1) in the cell culture supernatant upon CPP-P/CPP-S treatment. Elevated soluble CD59 and decreased release of basement membrane components might be considered as potential signs of dysfunctional endothelium. [ABSTRACT FROM AUTHOR]

Silver-modified zeolites have demonstrated promising properties for hydrocarbon feedstock valorization and the oxidation of organic compounds. Within the frame of the scientific interest for selective oxidation of light alkenes on metal-modified zeolites, the transformation of propene on Ag/H-ZSM-5 zeolite in the presence of molecular oxygen has been monitored by 13C (CP) MAS NMR spectroscopy at 296–773 K. Silver-allyl intermediate species have been detected by 13C CP/MAS NMR, indicating that Ag+ sites are involved in propene transformation. It is assumed that oxygen and propene compete for the Ag+ adsorption sites, thus prompting propene adsorption on zeolite Brønsted acid sites (BAS) and its further transformation by oligomerization and conjunct polymerization. Among the products of propene oxidation by molecular oxygen, only carbon dioxide has been detected by 13C MAS NMR, implying high activity of Ag/H-ZSM-5 in alkene total oxidation. It is thus inferred that silver-modified zeolite is not a promising catalyst for propene selective oxidation to propene oxide and carbonyl group containing organics. [ABSTRACT FROM AUTHOR]

Blood serum of patients with gastric (n = 68) and esophageal (n = 43) cancer was assessed for proteolytic fragments of IgG. Serum samples of 20 healthy donors were used as a control. We analyzed indicators of hemostasis (prothrombin time, fibrinogen, plasminogen activity, a2-antiplasmin activity, protein C activity) in blood plasma and the level of total IgG in the blood serum. The median IgG-LysK of healthy donors was lower than in esophageal cancer and in patients with gastric cancer. ROC-analysis showed high sensitivity (91%) and specificity (85%) in the group with esophageal cancer but 68% and 85%, respectively, in patients with gastric cancer. Analysis of false negatives IgG-LysK in cancer patients showed that most patients had an advanced stage of cancer accompanied by metastases. Total IgG in the plasma of patients with false-negative IgG-LysK values was 30% lower than in samples with positive values, while the level of a2-antiplasmin was increased and the prothrombin time was shorter. These changes in blood homeostasis may be the reason for an increase in the proportion of false-negative values of the IgG-LysK coefficient. Circulatory IgG-LysK levels increase in the early stages of such cancers as gastric and esophageal cancers. Thus, when used in a panel with other more specific markers for these pathologies, this indicator can significantly increase the early detection of cancer. [ABSTRACT FROM AUTHOR]

This paper uses a novel dataset on investments by the European Bank for Reconstruction and Development to quantify a (sizeable) trade‐off between the impact and financial objectives of a large lender. The unique feature of this dataset is ex ante records of impact. These are made at the early stages of work on each transaction alongside probability‐of‐default scores. Impact scores are further updated at the final approval stage with around 55 percent of transaction concepts translating into signed deals. We show that this approach delivers a simultaneous selection of debt investments on the quality of credit and impact with a sizable trade‐off between pursuing commercial and development objectives. For commercially riskier investments, impact characteristics have a greater bearing on the probability of an investment going ahead. We further use machine‐learning analysis to show that the impact of some investments is strengthened prior to project approval. [ABSTRACT FROM AUTHOR]

67Zn MAS NMR spectroscopy was used to characterize the state of Zn in Zn-modified zeolites ZSM-5. Two 67Zn enriched zeolite samples were prepared: by solid-state exchange with metal 67Zn (Zn2+/ZSM-5 sample) and by ion exchange with zinc formate solution (ZnO/H-ZSM-5 sample), both containing ca. 3.8 wt% Zn. The elemental analysis, TEM, and quantitative BAS and aluminum analyses with 1H and 27Al MAS NMR have shown that Zn2+/ZSM-5 contains zinc in the form of Zn2+ cations, while both ZnO species and Zn2+ cations are present in ZnO/H-ZSM-5 besides BAS. 67Zn MAS NMR has detected the signal of Zn in a tetrahedral environment from ZnO species for both the activated and hydrated ZnO/H-ZSM-5 zeolite. The signal of Zn in an octahedral environment was detected for the hydrated Zn2+/ZSM-5 and ZnO/H-ZSM-5 zeolites. This signal may belong to zinc cation [HOZn]+ or Zn(OH)2 species surrounded by water molecules. Quantitative 67Zn MAS NMR analysis has shown that only 27 and 38% of zinc loaded in the zeolite is visible for the activated and hydrated ZnO/H-ZSM-5 zeolite, and 24% of Zn is visible for the hydrated Zn2+/ZSM-5. Zinc in the form of ZnO species is entirely visible in both the activated and hydrated ZnO/H-ZSM-5 zeolite, while Zn2+ cations are not detected at all for the activated sample and only 29% of Zn2+ cations is visible for the hydrated zeolite. Detection of only a part of Zn2+ cations in the form of [HOZn]+ or Zn(OH)2 species in octahedral environment presumes only partial hydrolysis of the bond of Zn2+ cation with framework oxygen and further solvation of the Zn species formed at hydrolysis by the adsorbed water. [ABSTRACT FROM AUTHOR]

The UiO-66 (Zr) metal–organic framework (MOF) is of notable interest due to its facile synthesis, robustness under a wide range of chemical and physical conditions and its capability to separate industrially relevant hydrocarbons mixtures. However, the knowledge of the molecular mechanisms behind these process remains limited. Here, we present a combined experimental (2H NMR) and computational study of the molecular mobility, transport and adsorption of C5 alkanes isomers in a dehydroxylated UiO-66 (Zr) MOF. We show that the tetrahedral cages of the MOF are the preferred adsorption location for both n-pentane and isopentane. In a binary mixture of the isomers, isopentane interacts more strongly with the material leading it to occupy more of the tetrahedral cages than n-pentane, resulting in an isopentane/n-pentane adsorption selectivity of αads = 2 (at 373 K). At the same time, the microscopic diffusivity for n-pentane, Dn (En = 18 kJ mol−1), is significantly lower than for isopentane, Diso (Eiso = 28 kJ mol−1), which results in a high separation selectivity for a n-pentane/isopentane mixture of α ≈ 13 (at 300 K). This shows that the UiO-66 MOF is indeed a promising active material for use in light hydrocarbon separation processes. [ABSTRACT FROM AUTHOR]