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Objective: The mainstay therapy of hypothyroidism is levothyroxine (LT4). In most cases lifelong treatment is warranted, therefore, choosing adequate doses are of paramount significance. The purpose of this study was to assess several factors that have been proposed to influence LT4 therapy including etiology of hypothyroidism, gender, age, bodyweight, BMI, concomitant drug use, disease severity and time since diagnosis in patients with stable, adequately controlled hypothyroidism. Methods: In this cross-sectional study we analysed past medical history, anthropometric data and biochemical parameters reflecting thyroid function of patients with chronic hypothyroidism who were adequately treated (TSH levels in normal range) with LT4 for at least 6 months. Potential predictors of LT4 requirement were evaluated using uni- and multivariate linear modelling. Results: 191 individuals were enrolled in this study, who were divided into autoimmune (n = 147) and post-surgery (n = 44) groups. Mean age, time since diagnosis and LT4 dose (1.3 versus 1.1 mcg/kgBW) were significantly lower in the autoimmune group. In the post-surgery group age was the only significant (p = 0.016) predictor of LT4 dose. In the autoimmune group BMI (p = 0.001), time since diagnosis (p = 0.023), as well as their interaction (p = 0.012) turned out to be significant predictors of LT4 requirement. Conclusions: Our results implicate the necessity of differentiating between etiologies of hypothyroidism when starting or changing thyroxine replacement therapy. Patient in both groups required significantly lower doses of LT4 replacement, than previous reports suggest, to maintain stable euthyroidism. Distinctly different factors predicted hormone requirement in the two study groups.

Ever-growing cities constantly increase the distance between suburban regions and semi-urban areas on the perimeter of the cities, where traditional crop production can take place with relatively fewer restrictions. The implementation of ultra-short supply chains implies moving the means of crop production as close to inhabitants as possible. Two main directions can be identified as effective for increasing the food resilience of densely populated suburban areas; these are soil-based traditional urban agriculture and high-tech plant factories. Both approaches to crop production offer a certain level of integration with the built environment; however, these alternatives differ in terms of their contributions to environment modulation, agrobiodiversity, social well-being, and food resilience. Vertical farms can produce a high amount of nutritionally rich crops for direct use, although the involvement of inhabitants is minimal; therefore, they can be considered a service function without social advantages. Open-field plant production can contribute to the well-being of locals, but the yields are considered rather supplementary. The combination of both production approaches to strengthen common advantages is less likely; automated production technologies require a low number of highly qualified personnel; therefore, community plant factories cannot be considered possible contributors to urban social well-being in the future. [ABSTRACT FROM AUTHOR]

Tomato is one of the most important and frequently consumed vegetable species in Hungary, as well as a significant vitamin source throughout the year. Due to its antioxidant content, tomato consumption is related to the reduced occurrence of cardiovascular diseases and certain cancer types. In our study, four Hungarian tomato accessions [RCAT030275 (Cegléd), RCAT031012 (Veresegyház), RCAT031095 (Cigánd), RCAT054422 (Jánoshalma)] and a commercial cultivar (Hellfrucht) were investigated according to antioxidant capacity [ferric reducing power (FRAP), total phenol content (TPC) and radical scavenging activity (DPPH)], lycopene and ascorbic acid content. A two year (2013-2014) open field trial was carried out in the certified organic area of SZIE Soroksár Experimental and Educational Station. Our results showed that no significant differences were between the landraces and the variety in DPPH values, while TPC values were higher in both years in the landraces, especially in RCAT031095, and RCAT054422. The lycopene content of RCAT031012, RCAT031095 and RCAT054422 was also higher in both years than those of Hellfrucht. The results demonstrate that small-scale production of the investigated landraces could be marketable. [ABSTRACT FROM AUTHOR]

The effects of reduction by H2 and by heat treatment in vacuum and in O2 flow on Rh particle size changes of Rh/CeO2 samples were studied by X-ray photoelectron spectroscopy (XPS), high-resolution electron microscopy (HRTEM), and CO adsorption followed by diffuse reflectance infrared spectroscopy (DRIFTS). Low-temperature (373-423 K) reduction of Rh without agglomeration is demonstrated. An average particle size of 2.3 ± 1.1 nm was measured by HRTEM regardless of the metal loading (1-5%). On Rh/CeO2, a significant particle size increase of the Rh particles was detected on heating (773 K). In this work, we suggest that the temperature-induced surface decrease resulting from the sintering of Rh is favored only for well-dispersed particles. XP spectra revealed that the mobile oxygens of CeO2 fundamentally determine the oxidation state of the supported metals. At elevated temperature, the oxidation of the reduced support surface as well as the metal component takes place because of the segregation of ceria oxygens. When the aggregated particles were reoxidized, the redispersion of Rh was observed probably because of the formation of Rh-O-Ce bonds. [ABSTRACT FROM AUTHOR]

One weight percent of differently sized Au nanoparticles were deposited on two commercially available TiO2 photocatalysts: Aeroxide P25 and Kronos Vlp7000. The primary objective was to investigate the influence of the noble metal particle size and the deposition method on the photocatalytic activity. The developed synthesis method involves a simple approach for the preparation of finely-tuned Au particles through variation of the concentration of the stabilizing agent. Au was deposited on the TiO2 surface by photo- or chemical reduction, using trisodium citrate as a size-tailoring agent. The Au-TiO2 composites were synthetized by in situ reduction or by mixing the titania suspension with a previously prepared gold sol. The H2 production activities of the samples were studied in aqueous TiO2 suspensions irradiated with near-UV light in the absence of dissolved O2, with oxalic acid or methanol as the sacrificial agent. The H2 evolution rates proved to be strongly dependent on Au particle size: the highest H2 production rate was achieved when the Au particles measured ∼6 nm. [ABSTRACT FROM AUTHOR]

The primary objective of the experiments was to investigate the differences in the photocatalytic performance when commercially available Aeroxide P25 TiO2 photocatalyst was deposited with differently sized Pt nanoparticles with identical platinum content (1 wt%). The noble metal deposition onto the TiO2 surface was achieved by in situ chemical reduction (CRIS) or by mixing chemically reduced Pt nanoparticle containing sols to the aqueous suspensions of the photocatalysts (sol-impregnated samples, CRSIM). Fine and low-scale control of the size of resulting Pt nanoparticles was obtained through variation of the trisodium citrate concentration during the syntheses. The reducing reagent was NaBH4. Photocatalytic activity of the samples and the reaction mechanism were examined during UV irradiation (λmax = 365 nm) in the presence of oxalic acid (50 mM) as a sacrificial hole scavenger component. The H2 evolution rates proved to be strongly dependent on the Pt particle size, as well as the irradiation time. A significant change of H2 formation rate during the oxalic acid transformation was observed which is unusual. It is probably regulated both by the decomposition rate of accumulated oxalic acid and the H+/H2 redox potential on the surface of the catalyst. The later potential is influenced by the concentration of the dissolved H2 gas in the reaction mixture. [ABSTRACT FROM AUTHOR]

Abstract: The photo-induced vapor-phase decompositions of formic acid and methyl formate were investigated on pure, N-doped and Au-promoted TiO2. Infrared (IR) spectroscopic studies revealed that illumination initiated the decomposition of adsorbed formate formed in the dissociation of formic acid and located mainly on TiO2. The photocatalytic decompositions of formic acid and methyl formate vapor on pure TiO2 occurred to only a limited extent. The deposition of Au on pure or doped TiO2 markedly enhanced the extent of photocatalytic decomposition of formic acid. The main process was dehydrogenation to give H2 and CO2. The formation of CO occurred to only a very small extent. Addition of O2 or H2O to the formic acid decreased the CO level from ∼0.8% to ∼0.088%. Similar features were experienced in the photocatalytic decomposition of methyl formate, which dissociated in part to give surface formate. Experiments over Au deposited on N-doped TiO2 revealed that the photo-induced decomposition of both compounds occurs even in visible light. [Copyright &y& Elsevier]

In an attempt to model occupational and environmental Mn exposures and their possible interaction, young male Wistar rats were exposed to Mn by oral administration in dissolved form (MnCl(2)·4H(2)O, 14.84 and 59.36 mg/kg b.w.) and by intratracheal application of MnO(2) nanoparticles (2.63 mg/kg b.w.). After 3 and 6 weeks oral, or 3 weeks oral plus 3 weeks intratracheal, exposure, general toxicological, and electrophysiological tests were done. Body weight gain was significantly reduced after 6 and 3 plus 3 weeks exposure, but the effect of the latter on the pace of weight gain was stronger. Organ weights signalized systemic stress and effect on lungs. Changes in evoked electrophysiological responses (cortical sensory evoked potential and nerve action potential) indicated that the 3 plus 3 weeks combined exposure caused equal or higher changes in the latency of these responses than 6 weeks of exposure, although the calculated summed Mn dose in the former case was lower. The results showed the importance of the physicochemical form of Mn in determining the toxic outcome, and suggested that neurofunctional markers of Mn action may indicate the human health effect better than conventional blood Mn measurement.

Ghrelin: a new peptide regulating the neurohormonal system and energy homeostasis. Research leading to the identification of ghrelin started with the discovery of growth hormone secretagogues, continued with the description of ghrelin receptors and ended with description of the chemical structure of ghrelin. However, several aspects concerning the role of ghrelin in physiology and pathophysiology are still under investigation. The majority of ghrelin is produced in the stomach, but it is also expressed in the hypothalamus, pituitary, intestine, kidney, heart, pancreas and gonads. Ghrelin stimulates growth hormone secretion via growth hormone secretagogue receptors, and it increases appetite. Ghrelin secretion in the stomach depends on both acute and chronic changes in energy balance. Presently available data support the hypothesis that the stomach, in addition to its important role in digestion, not only influences pituitary hormone secretion via ghrelin production but it also sends orexigenic (appetite increasing) signals to hypothalamic nuclei involved in the regulation of energy homeostasis. In addition to these main effects, ghrelin influences the cardiovascular, gastrointestinal, reproductive and endocrine functions. It can be anticipated that further research on the physiological and pathophysiological role of ghrelin will lead to a better understanding of neurohormonal processes and the central regulation of energy homeostasis.