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One-pot depolymerisation of lignin, extracted from Miscanthus plants under acidic (formic acid lignin, FAL) or basic (ammonia lignin, AL) conditions, over Ni- and/or Nb-doped SBA-15, was the subject of this study. The aforementioned acid catalysts prepared by sol–gel method were characterized by SEM–EDX, ATR-FTIR, Raman, XRD, N2 adsorption/desorption isotherms, CO2-TPD and NH3-TPD techniques. The increase in acidity due to the insertion of Nb into the SBA-15 structure promoted the selective cleavage of β–O–4 from ammonia lignin, leading to aromatic monomer yields up to 22 wt% in 6 h at 180 °C under 50 atm H2. The catalytic performances of Ni-Nb-SBA-15 as well as its stability were influenced by the chemical composition of the lignin sample as results of its extraction from the Miscanthus plant. [ABSTRACT FROM AUTHOR]

Polysilsesquioxanes are extensively studied as durable and anti-adherent coatings for medical devices due to their superhydrophobic properties. However, their particular influence on the thermo-mechanical properties and biocompatibility of poly(lactic acid) (PLA)-based materials obtained by melt compounding is scarce. Herein, a facile and promising method to improve the performances of PLA for biomedical applications via the incorporation of different mass proportions of POSS nanoparticles with allyl-heptaisobutyl (AH-POSS) substituent through a melt-blending technique is proposed. The thermal, morpho-structural, mechanical properties at room (RT) and body temperatures (BT), and in vitro biocompatibility of the developed PLA/AH-POSS nanohybrids were investigated. AH-POSS nanoparticles were found to have simultaneous nucleation and plasticizing effects on the PLA nanohybrids, inducing enhanced thermal resistance and easy control of crystallinity while preserving PLA's biocompatibility. An interesting effect of AH-POSS on the mechanical properties of PLA at body temperature was observed. These results indicate the considerable potential of the PLA/AH-POSS nanohybrids obtained by melt compounding in the fabrication of biomedical devices. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the changes caused by the administration of ketoprofen to albino NMRI mice on some hematological, biochemical, and structural parameters. For this purpose, the mice were divided into two lots: a control batch and an experimental batch to which ketoprofen was administered subcutaneously at a dose of 10 mg/kg body weight per day for 7 days. A decrease in erythrocyte number and hemoglobin was observed altogether with the increase in white blood cells. Blood biochemistry indicates increased blood glucose, cholesterol, and triglyceride levels. Enzyme values (AST, ALT, and ALP) show a significant increase. Hepatic pathology reveals the enlargement of sinusoidal capillaries, the presence of leukocyte infiltrates associated with necrosis zones. [ABSTRACT FROM AUTHOR]

Metallic nanoparticles represent an important area of research, as their unique properties can be tuned for the desired application. Several "green" methods were proposed for obtaining metallic nanoparticles, including phytosynthesis (using natural extracts) and radiation-assisted synthesis. The present work studies the differences in terms of biological properties (antimicrobial properties, cytotoxicity and phytotoxicity) of silver nanoparticles obtained using those two very different approaches. The obtained nanoparticles were analytically characterized using transmission electron microscopy, X-ray diffraction and UV–Vis spectrometry, for the evaluation of their morphological properties, which can be linked to their biological properties. The results showed that the radiation-assisted path led to smaller dimension nanoparticles (7–10 nm), while the phytosynthesis led to nanoparticles with 10–12 nm in diameter (as determined by XRD), depending on the used materials. The phytosynthesized nanoparticles seemed to be more effective antimicrobial agents (effect studied against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 10231), while those obtained by the radiological path had a stronger mitoinhibitory effect. The growth of the root and of the stem was less affected by the samples containing radiological synthesized nanoparticles. The differences in terms of biological activity observed when modifying the agents used for the reduction of the metallic salt are also discussed. [ABSTRACT FROM AUTHOR]

Green nanoparticles are currently thoroughly researched due to the multiple advantages of phytosynthesis, on the one hand, and the potential beneficial or adverse effects, on the other. In this context, our study investigates the potential for the phytosynthesis of gold and silver nanoparticles of the ethanol and methanol extracts from leaves of Aconitum toxicum Rchb., as well as the enhancement of the antioxidant potential and the influence on the cytotoxic and genotoxic effects of the extracts through the action of the synthesized nanoparticles. The nanoparticles obtained were characterized using analytical techniques as UV–Visible spectrometry, X-ray diffraction, X-ray fluorescence, electron microscopy (SEM and STEM). The HPLC analysis of extracts revealed that the methanol extracts contained a higher aconitine level. The alcoholic extracts from leaves of A. toxicum Rchb. exerted mitodepressive effect and the phytomediated synthesis of Ag and Au nanoparticles diminished mitoinhibitory effect of the extracts, dependent on nanoparticles size and type. The mitostimulatory potential of the extracts supplemented with Ag nanoparticles was higher compared with that of the extracts with Au nanoparticles. In general, an influence of the extract composition on both the phytosynthesized nanoparticles and on the evaluated properties was observed, the ethanolic extract leading to gold nanoparticles with smaller dimension, while the silver nanoparticles had similar dimensions for both extracts studied. In the same time, the antioxidant properties of the extracts increased with the phytosynthesis process, a higher increase being observed upon the phytosynthesis of the silver nanoparticles (17% increase for the ethanolic extract and, respectively, 12% for the methanolic extract). [ABSTRACT FROM AUTHOR]

The objective of the study is to screen for morphological, biochemical and histological changes induced by six widely used pesticides (Reldan 40EC, Actara 25WG, Tilt 250EC, Champion 50WG, Fusilade Forte, Dual Gold 960EC) in the amphibian species Pelophylax ridibundus (Pallas, 1771). Highly degenerative changes were observed in animals cultured at 22–24°C, compared to those cultured at 4–6°C. The hepatosomatic index increased upon exposure to almost all of the pesticides, the erythrocyte number decreased upon exposure to all pesticides except Reldan 40EC, while leucopenia was observed only for Reldan 40EC and Actara 25WG. Hyperglycemia was observed upon administration of pesticides (except Champion 50WG and Fusilade Forte, for which hypoglycemia is registered), while a decrease in cholesterol levels was induced by nearly all pesticides. Triglycerides varied only slightly. The results suggest that chronic pesticides exposure can lead to alteration of various indices, as well as to hepatic lesions in amphibians. [ABSTRACT FROM AUTHOR]

The present work is focused on thermoanalytical investigations as thermogravimetric analysis (TG) and derivative thermal analysis (DTG), applied for the characterization of some samples collected from archaeological sites (Brasov and Trofeum Traiani) located in different regions of Romania. New informations derived about ceramic technologies concerning raw materials and binding materials (mineralogical components) have been obtained. All these experimental results have been correlated with related techniques as X-ray diffraction (XRD), energy-dispersive X-ray fluorescence (EDXRF) and inductively coupled plasma—atomic emission spectrometry (ICP-AES). By progressive heating in static air atmosphere and in the temperature range of 20–800 °C, all investigated materials exhibit three main successive processes, associated with the dehydration and thermo-oxidative degradations. The rate of the first thermooxidative process, temperatures corresponding to the maximum rate of the second thermooxidative process and shrinkage temperature were associated with the damage of the investigated materials due to environmental impact. Heating also affects the contact between the fine-sized clay matrix and mineral clast fragments, appearing in reaction rims, sometimes showing newly formed phases. The temperature at which ancient ceramics and pottery were fired varies over a wide range (600–800 °C) depending on the type of clay used, although firing temperatures not above 30–400 °C have also been suggested. Clay minerals, as the main material for production of ceramics and pottery, show some characteristic reactions (dehydroxylation, decomposition, transformation) in the course of firing (heating effects) and several thermoanalytical criteria can be used for reconstruction of former production conditions. [ABSTRACT FROM AUTHOR]