A p53 transzkripciós faktor család szerepe teratogén vírusok sejtkárosító hatásának molekuláris mechanizmusában = The role of the p53 transcription factor family in the molecular mechanism of cytopatic effect elicited by teratogenic viruses

Kutatásaink célja a rubeolavírus (RV), a vesicularis stomatitis vírus (VSV) és a herpes simplex vírus (HSV) sejtkárosító és teratogén hatásának jobb megértése volt, ezért azt tanulmányoztuk, hogy ezen vírusok befolyásolják-e a p63 és a Bcl-2 családba tarozó fehérjék expresszióját. RV fertőzés hatására, mindegyik TAp63 izoforma szintje emelkedett, míg a deltaNp63alfa szintje csökkent Vero sejtekben. VSV fertőzés hatására, a Bcl-2 és a Bax-alfa szintje csökkent, a p53 és a p63 szintje nem változott, míg a p18 Bax expressziója jelentős mértékben emelkedett WK sejtekben. VSV-vel fertőzött HaCaT sejtekben a deltaNp63alfa és a mutáns p53 szintje csökkent, a Bcl-2 nem változott, míg a Bax-alfa és a p18 Bax expressziója fokozódott. HSV fertőzés hatására, a deltaNp63alfa szintje csökkent, míg néhány más p63 izoforma expressziója fokozódott. Továbbá, a HSV fertőzés a Bax-béta szintjének emelkedését váltotta ki. Eredményeink azt mutatják, hogy mindhárom vírus befolyásolja a p63 izoformák és a Bcl-2 családtagok arányát, de egymástól eltérő módon. A különböző p63 izoformák szintjének változása fontos szerepet játszhat ezen vírusok sejtkárosító és teratogén hatásában. | We have investigated the effects of rubella virus (RV), vesicular stomatitis virus and herpes simplex virus (HSV) on the expressions of p63 isoforms and Bcl-2 family members, in an effort to gain some insight into the cytopathic and teratogenic effects of these viruses. Our studies have shown that RV-infected Vero cells displayed highly elevated levels of each TAp63 isoform and a decreased level of deltaNp63alpha. The levels of Bcl-2 and Bax-alpha were decreased, p53 and p63 remained unaffected, while the expression of p18 Bax was increased in VSV-infected WK cells. The levels of deltaNp63alpha and mutated p53 were decreased, Bcl-2 remained unaffected, while the expressions of Bax-alpha and p18 Bax were increased in VSV-infected HaCaT cells. HSV-infected HaCaT cells exhibited decreased level of deltaNp63alpha and highly elevated levels of some other p63 isoforms. Moreover, HSV infection caused a significant increase in the expression level of Bax-beta. Taken together, our data demonstrate that RV, VSV and HSV infections alter the stoichiometric ratios of the p63 isoforms and Bcl-2 family members, but in different ways. The dysregulated patterns of p63 expression observed in the infected cells may represent mechanisms whereby these viruses exert their cytopathic and teratogenic effects

Formation of gold/silver composite nanoparticles by pulsed laser ablation of gold–silver layered films in liquid

Nanoparticles of high purity can be produced from a variety of materials by pulsed laser ablation of solids in liquid. Composite nanoparticles are of great importance in various applications such as catalysis or biomedicine and the process of their formation is still a subject of intense research. In this work, gold/silver composite nanoparticles were synthesized in aqueous media by ns pulsed laser ablation of gold–silver multilayer targets with different absolute layer thicknesses and layer thickness ratios. The generated nanoparticles showed a log-normal distribution of sizes, with average diameter in the 20–40 nm range and standard deviation of 9–30 nm. By comparing the UV–VIS absorbance spectra of the nanoparticle colloids with two theoretical calculations (based on the Mie and the BEM model), it was found that there is a direct correlation between the average Au and Ag content of the nanoparticles and the composition of the films on the substrate. Assuming thermal ablation, our model calculations showed that there is a maximum thickness of the top layer up to which both layers can be ablated simultaneously and alloy nanoparticles can be produced

Facile and versatile substrate fabrication for surface enhanced Raman spectroscopy using spark discharge generation of Au/Ag nanoparticles

A simple, one-step gas phase technique for the fabrication of low-cost substrates with tunable plasmonic enhancement is proposed exploiting the unique peculiarities of spark discharge nanoparticle generation in particle mixing and the ease of particle deposition onto glass microfiber filters. The applicability of the spark-based technique to produce substrates for surface enhanced Raman measurements based on Au/Ag binary nanoparticles is discussed. Our results prove that considerable signal enhancement can be achieved over a large surface area, which can be conveniently tuned due to the inherent ability of the spark generator to mix two or more materials. This versatility in particle generation is well complemented by the direct deposition of the nanoparticles onto a filter medium, which makes the proposed method a low-cost and appealingly simple way for fabricating robust substrates for Raman-based applications. © 2020 The Author

Application of pulsed laser ablation (pLA) for the size reduction of non‑steroidal anti‑inflammatory drugs (nSAiDs)

We studied the application of pulsed laser ablation (pLA) for particle size reduction in non‑steroidal anti‑inflammatory drugs (NSAIDs). Grinding of the poorly water‑soluble NSAID crystallites can considerably increase their solubility and bioavailability, thereby the necessary doses can be reduced significantly. We used tablets of ibuprofen, niflumic acid and meloxicam as targets. Nanosecond laser pulses were applied at various wavelengths (KrF excimer laser, λ=248 nm, FWHM=18 ns and Nd:YAG laser, λ1=532 nm/λ2=1064 nm, FWHM=6 ns) and at various fluences. FTIR and Raman spectra showed that the chemical compositions of the drugs had not changed during ablation at 532 nm and 1064 nm laser wavelengths.The size distribution of the ablated products was established using two types of particle size analyzers (SMPS and OPC) having complementary measuring ranges.The mean size of the drug crystallites decreased from the initial 30–80 µm to the submicron to nanometer range. For a better understanding of the ablation mechanism we made several investigations (SEM, Ellipsometry, Fast photography) and some model calculations. We have established that PLA offers a chemical‑free and simple method for the size reduction of poorly water‑soluble drugs and a possible new way for pharmaceutical drug preformulation for nasal administration