Studies on the Effect of Graphene Oxide Deposited on Gold and Nickel Microsieves on Prostate Cancer Cells DU 145

This work shows the effect of graphene oxide deposition on microsieves’ surfaces of gold and nickel foils, on DU 145 tumor cells of the prostate gland. The sieves were made by a laser ablation process. The graphene oxide (GO) deposition process was characterized by the complete covering of the inner edges of the microholes and the flat surface between the holes with GO. Electron microscanning studies have shown that due to the deposition method applied, graphene oxide flakes line the interior of the microholes, reducing the unevenness of the downstream surfaces during the laser ablation process. The presence of graphene oxide was confirmed by Fourier infrared spectroscopy. During the screening (sieving) process, the microsieves were placed in a sieve column. Gold foil is proven to be a very good material for the screening of cancer cells, but even more so after screening as a substrate for re-culture of the DU 145. This allows a potential recovery of the cells and the development of a targeted therapy. The sieved cells were successfully grown on the microsieves used in the experiment. Graphene oxide remaining on the surface of the nickel sieve has been observed to increase the sieving effect. Although graphene oxide improved separation efficiency by 9.7%, the nickel substrate is not suitable for re-culturing of the Du 145 cells and the development of a targeted therapy compared to the gold one.     

Synthesis of 5-nitro- and 5-aminobenzimidazolone-2

The pure mononitro derivative of benzimidazolone-2 can be obtained only when the nitration reaction is carried out in mild conditions, otherwise di-, tri- and tetranitro derivatives are also formed. The results of our studies derived optimum conditions for the nitration process necessary to obtain pure 5-nitrobenzimidazolone-2.     

New melamine resins. I. Synthesis of reactive solvents for melamine

Some results are presented on the studies of reactive solvents for melamine obtained from acetone and formaldehyde in the presence of potassium bicarbonate or triethylamine as catalysts. The chemical structure of the solvents, as well as their ability to dissolve melamine, have been determined. The mechanism of melamine dissolution in the reactive solvents has been analyzed by using the ¹H-NMR technique. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1039–1049, 1998     

Contrast attenuation coefficient as a parameter enabling determination of range of visibility in smoke

The contrast attenuation coefficient characterizes smoke production properties of a material. These properties are closely connected with a contrast of luminance of a scene observed in a smoky medium, the range of visibility, and mass concentration in an environment volume. The range of visibility determines a person's chances of moving about in a fire zone. This paper presents considerations on conditions of visibility in smoky compartments, a method of the contrast attenuation measurement and test results for some materials. © 1997 John Wiley & Sons, Ltd.     

Bioactive compound levels and sensory quality of partially skimmed organic yoghurts: Effects of the milk treatment,production season and starter culture*

The aim of the study was to assess the physicochemical properties, texture, colour and sensory quality of organic yoghurts with regard to the milk treatment (raw milk obtained directly from organic farms, partially skimmed and heat‐treated in the laboratory vs organic milk purchased in the shop that was pasteurised in a dairy), production season and starter culture. The yoghurts produced on the basis of bulk milk obtained from farms during the spring/summer season proved to be of greater nutritional value and had higher content of bioactive whey proteins, except for β‐lactoglobulin, and lipophilic vitamins than retail milk.     

Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis.