Wyniki wyszukiwania - BazTech

1

Rat cancer cells necrosis induced by ultrasound

Secomski W., Bilmin K., Kujawska T., Nowicki A., Grieb P.

Hydroacoustics

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2014

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Vol. 17

179--186

EN

Sonodynamic therapy is the ultrasound dependent enhancement of the cytotoxic activities of certain drugs called sonosensitizers. The study of therapeutic efficacy of ultrasound is always preceded by in-vitro tests. In this work, two in-vitro sonication procedures were compared. One with the transducer positioned bellow the cell colony, radiating upward, with standing wave reflected from the water-air surface, the second, in the free field conditions. Efficiency of the cancer cells necrosis caused by ultrasound was compared with acoustical field intensity ISPTA measured by a hydrophone. The standing wave conditions effectively increased the intensity of the ultrasonic wave at the level of cells. To achieve 50% of cell viability, the intensity ISATA, decreased from 5.8 W/cm2 to 0.3 W/cm2. In summary, sonication in the standing wave conditions can effectively and reproducibly destroy cells by ensuring the sterility and without the risk of overheating.

2

Assessment of Metabolite Concentrations Changes in Rat Brain after Intravenous CDPcholine Injection Using Magnetic Resonance Spectroscopy in vivo

Kulinowski P., Labak M., Majcher K., Herbik A., Grieb P., Jasiński A.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 7

1125-1132

EN

CDPcholine (citicoline, CDPCho) shows beneficial effects in various Central Nervous System (CNS) injury models and neurodegenerative diseases. Previous studies demonstrate conflictingMagnetic Resonance Spectroscopy (MRS) reports regarding the impact of different choline-containing compounds and its doses on brain metabolites. This preliminary study was designed to evaluate concentration changes of brain MR-visible metabolites following intravenous CDPCholine. Twelve healthy rats treated with CDPCholine in three subsequent doses of 1gram/kg eachwere examined using 1Hand 31P MRS in vivo. Following intravenous CDPCholine administration there was a statistically significant increase of the Cho/Cr ratio after first CDPCholine injection. The evidence of CDPcholine influence on brain metabolites has been shown.

3

Estimation of antioxidative properties of phenylacetic acids using ion-exclusion chromatography

Głód B. K., Grieb P.

Acta Chromatographica

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2005

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No. 15

258-268

EN

Cellular oxidative stress has been implicated as a key mechanism of cell differentiation provoked by several compounds (doxorubicins, fibrades, edelfosine). Phenylacetate and its derivatives in submillimolar to millimolar concentrations induce cell differentiation. Ion-exclusion chromatography is widely used for separation and analysis of weak acids. We applied it to the analysis of phenylacetic acids and to the determination of the hydroxyl radical-trapping potential of some of these compounds. Their total antioxidant potential for peroxy radicals was also measured using a photometric method. It was found that phenylacetates are weak antioxidants and in the concentrations which induce cell differentiation effects may substantially reinforce intracellular antioxidative potential.

4

Synteza biokompatybilnych kopolimerów i ich zastosowanie w kontrolowanym uwalnianiu sterydów i analogów nukleozydów

Bero M., Kasperczyk J., Dobrzyński P., Grieb P., Kryczka T., Ryba M., Buntner B., Nowak M.

Chemik

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2004

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Vol. 57, nr 2

49-54

PL

Publikacja jest przeglądem naszych wyników dotyczących syntezy i zastosowania biodegradowalnych i biokompatybilnych kopolimerów w procesie kontrolowanego uwalniania leków. Przedstawiono nowe metody syntezy kopolimerów, bez zastosowania toksycznych inicjatorów zawierających cynę. Stwierdzono możliwość uzyskania stałej szybkości uwalniania leków takich jak nukleozydy i sterydy.

EN

This publication is a review of our results about synthesis and application of biodegradable and biocompatible copolymers used in the controlled drug release process. New methods of copolymers synthesis without toxic tin compounds initiators were presented. Application of obtained copolymers allow to release nucleoside analogs and some steroids at constant speed.

5

Kopolimery laktydu, glikolidu i eta-kaprolaktonu nie zawierające metali ciężkich : synteza, własności i zastosowanie w procesie kontrolowanego uwalniania analogów nukleozydów

Bero M., Dobrzyński P., Kasperczyk J., Grieb P., Kryczka T., Ryba M., Walski M.

Inżynieria Biomateriałów

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2002

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R. 5, nr 23-25

21-22

6

Modified analytical method for hydroxyl radicals using spin trapping and ion exclusion chromatography

Głód B. K., Grieb P.

Chemia Analityczna

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2002

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Vol. 47, No. 3

399-407

EN

Ion exclusion chromatography (IEC) is the predestinated chromatographic technique for weak acids separation and analysis. Preliminary results are presented concerning the application of IEC to the determination of hydroxyl free radicals with the use of hydroxybenzoate spin trapping. Products of the reaction, dihydroxycarboxylic acids, are retained due to the mixed ion exclusion and PI-electron interaction retention mechanism. The method was applied to the determination of hydroxyl radical trapping potential of some organic solvents, phenylacetates, and biogenic polyamines. The later were found to scavenge efficiently hydroxyl radicals, which property may contribute to their cyto- and neuroprotective properties.

PL

Chromatografia wykluczaniajonowego jest dogodną techniką do rozdzielania i oznaczania słabych kwasów. Wstępne wyniki badań wykazały przydatność tej techniki do oznaczania wolnych rodników hydroksylowych po ich pulapkowaniu spinowym hydroksybenzoesami. Mechanizm retencji produktów reakcji, kwasów dihydroksykarboksylowych, jest mieszany, jonowo-wykluczający i związany z Pi-elektronowym oddziaływaniem pierścieni aromatycznych z żywicą. Opracowaną metodę zastosowano do oznaczania potencjału antyoksy-dacyjnego niektórych rozpuszczalników organicznych i poliamin biogennych. Okazało się, że poliaminy są efektywnymi zmiataczami rodników hydroksylowych co może tłumaczyć ich cyto- i neuroprotekcyjne właściwości.