Subacute effects of a food flavour on fish model

Dóra Bencsik1,2, Balázs P Szabó1, Gyöngyi Gazsi2, Béla Urbányi2, Béla Szende3, Gergely Rácz3, Antal Véha1, Zsolt Csenk

P53, CD95, cathepsin and survivin pathways in Fuchs dystrophy and pseudophakic bullous keratopathy corneas

Our purpose was to elucidate the pathways of apoptosis of corneas with Fuchs’ dystrophy and pseudophakic bullous keratopathy. Sixteen corneal buttons (14 patients, median age 73 years) with Fuchs’ dystrophy, 13 with pseudophakic bullous keratopathy (PBK) (13 patients, median age 69 years) and 8 buttons (8 patients, median age 59 years) from enucleated eyes with chorioideal melanoma (controls) were analysed histologically. Immunohistochemical analysis was performed to investigate the expression of p21, p27, p63, survivin, CD95, cathepsin, bax, bcl-2 and Ki67. Positive immunohistochemical reactions were detected in epithelial cells of the corneas, but keratocytes and endothelial cells were not positive in any of the groups or stainings. The number of p27 and survivin positive epithelial cells was significantly lower (p=0.048 and 0.041) and the number of cathepsin positive epithelial cells was significantly higher (p=0.004) in Fuchs’ dystrophy corneas compared to controls. In pseudophakic bullous keratopathy, p21 and p27 positive epithelial cells were present in a significantly lower (p=0.02 and 0.005) number than in controls. We conclude that genetically programmed cell death is related to the p27, cathepsin and survivin pathways in Fuchs’ dystrophy and to the p21 and p27 pathways in pseudophakic bullous keratopathy

Könyvismertetések = Book Reviews

1. John Piper: Mother Killers. Edited: 2006. Book Guild Publishing 2. Vetési Ferenc – Dobos-Kovács Mihály: Állatorvosi patológiai képes album I. Emlős patológia Vet Image Kft. 2006. 3. Kiss László: Kazinczy sógora, Zemplén főorvosa: Dercsényi Jáno

P21, p27, bax, cathepsin and survivin pathways in macular dystrophy corneas

The purpose of our study was to elucidatepathways of genetically programmed cell death(apoptosis) in corneas with macular dystrophy.10 corneal buttons (10 patients) with maculardystrophy and 8 buttons (8 patients) from enucleatedeyes with chorioideal melanoma (controls) wereanalysed histologically. Immunohistochemical analysiswas performed to investigate the presence of p21, p27,bax, cathepsin and survivin proteins. The number ofpositive cells was determined by analysis of 100 cellsand given in percentages.The bax protein was present in 25.6% of epithelialcells in macular dystrophy corneas but was absent incontrols. P21 and p27 were found in 35.7 and 87.5% ofepithelial cells of macular dystrophy corneas,respectively, but again not in control tissue. In contrast, alower percentage of cathepsin-positive (30.7% vs58.8%) and survivin-positive cells (37.6% vs 52.1%)were present in epithelial cells of macular dystrophycorneas than in control epithelial cells. The differencereached statistical significance in the expression of p21and p27 genes (p<0.05 in both).P21 was positive in 3% of keratocytes, p27 in 1% ofendothelial cells of macular dystrophy corneas butnegative in controls (0%). Bax, cathepsin and survivinimmunopositivity was not detected in keratocytes orendothelial cells of either group. We conclude that the down-regulation of p21, p27and cathepsin in epithelial cells of macular dystrophycorneas may be related to defense mechanisms againstapoptotic cell death

The quantitative characterization of free radical sources and traps by electromigration applications

Nowadays, very diverse human activities generate urgent demands for fast, sensitive reliable innovative tools capable of detecting major industrial, military, and other dangerous products. An important part of these compounds are free radicals. Capillary electrophoresis (CE), especially in its miniaturized format (lab-on-a-chip), and other electromigration methods offer special possibilities to resolve this problem. These measurements have a great opportuness because of very wide chemical and biological role of free radicals. Several compounds, e.g. monomers and some biologically important groups (as are nitrones) oppose oxidative challenges by virtue of their trap very rapidly oxygen- or carbon-centered radicals and generating other radical species which are stable and biochemically less harmful than the original ones. In many cases, conventionally, the relative trap capacity is measured against tert.-butylhydroperoxide (TBH). In this lecture are presented numerous important free radical species (active oxygen–, nitrogen- and carbon-centered ones, as HO, NO etc) and their adequate in vitro and in vivo applied bioanalytical methods, including liquid chromatography with electrochemical detection and mass spectrometry, gas chromatography with mass spectrometry, capillary electrophoresis, electron spin resonance and chemiluminescence analysis. A simple and highly sensitive method is the capillary zone electrophoresis with amperometric detection (CZE-AD); It was introduced to determine indirectly OH by analysing its reaction products with salicylic and dihydroxybenzoic acids. Hydroxylated radical products of these acids are often used as a relative measurement in free radical research. Accurate determination of pK(a) values is important for proper characterization of newly synthesized molecules. CZE method was used for determination of their values. Are initiated new research fields as Fenton-, electro-Fenton and photoelectro-Fenton chemistry and foreseen their perspectives. Nitric oxide is an important cell signaling molecule in physiology and pathophysiology. An indirect method for monitoring nitric oxide (NO) by determining nitrate and nitrite by microchip capillary electrophoresis (CE) with electrochemical (EC) detection has been developed. The amount of nitrite formed in this reaction (analyzed by capillary electrophoresis) was compared with the amount of oxygen consumed (measured by polarography). Were observed a linear relationship between the amount of consumed oxygen and the amount of nitrite formed in the measured range. These results demonstrate that polarographic measurements of the amount of oxygen consumed in the reaction with NO could be used to estimate the concentration of dissolved NO in authentic media. Polarography is an adequate method also to quantitative kinetic study of the free radical activity and of the trapping capacity of different compounds. This method is based on measure of the catalytic polarografic current of Fe(III) in the presence of free radical sources (TBH, hydrogen-peroxydes), and their traps. Personal contribution of the authors in this field is discussed