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1

No evidence of the long-term in vitro toxicity of Aeroxide P25 TiO2 nanoparticles in three mammalian cell lines despite the initial reduction of cellular mitochondrial activity

Męczyńska-Wielgosz Sylwia, Bartłomiejczyk Teresa, Grądzka Iwona, Sommer Sylwester, Węgierek-Ciuk Aneta, Lankoff Anna, Sikorska Katarzyna, Wojewódzka Maria, Dobrzyńska Małgorzata, Kruszewski Marcin

Nukleonika

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2024

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Vol. 69, No. 1

13--22

EN

We studied the effects of Aeroxide P25 titanium dioxide nanoparticles (TiO2 NPs) with a diameter of 21 nm on induction of DNA damage and long-term survival of three human cell lines: hepatocellular liver carcinoma HepG2, colorectal adenocarcinoma HT29 and lung carcinoma A549. The endpoints examined were DNA breakage estimated by the comet assay and oxidative base damage recognized by formamide-pyrimidine glycosylase (FPG) estimated with the FPG+ comet assay, frequencies of histone H2AX foci and micronuclei, apoptosis, cell metabolic activity measured by mitochondrial activity (MTT) assay and long-term survival measured by colony-forming ability. Each cell line had a different pattern of DNA breakage and base damage vs. nanoparticle (NP) concentration and treatment time. There was no increase in the frequencies of histone H2AX foci and micronuclei as compared to those in the untreated cells. In parallel with these results, no induction of apoptosis has been found in none of the cell lines tested. The reported experiments provided no evidence of the long-term in vitro toxicity of Aeroxide P25 TiO2 NPs, despite a slight decrease in mitochondrial activity and cell survival during the first 72 h.

2

Genotoksyczność odcieków ze składowiska odpadów komunalnych w Kozodrzy wobec celomocytów E. fetida

Jurczyk Ł.

Archiwum Gospodarki Odpadami i Ochrony Środowiska

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2014

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Vol. 16, nr 3

33--40

PL

Jednym z największych problemów eksploatacyjnych na składowiskach są odcieki, powstające podczas wymywania substancji zawartych w odpadach i produktach ich rozkładu przez wodę penetrującą złoże, a ich złożony charakter wymaga stosowania do oceny ryzyka środowiskowego oprócz analiz chemicznych, testów na układach biologicznych. Celem pracy było zbadanie wpływu odcieków pochodzących ze zorganizowanego, ustabilizowanego składowiska, w dużym zakresie rozcieńczeń, na uszkodzenia materiału genetycznego jąder komórkowych E. fetida. Uszkodzenia indukowane przez odcieki w czasie krótkiej, 2h ekspozycji były niewielkie ale zauważalne, analiza statystyczna wykazała istotne (p>0,001) różnice wartości momentu kometowego i intensywności świecenia pomiędzy próbą zerową, a stężeniami ≥6,2%.

EN

One of the biggest problems of operating a landfill is leachate, resulting from the leaching of substances contained in waste and products of their decomposition by water penetrating the bed. The complex nature of this mixture requires both the chemical analyzes and tests on biological systems to assess environmental risk. The aim of the study was to investigate the effect of leachate derived from an organized, stabilized landfill, in a large range of dilutions, on nuclear DNA damage in the E. fetida coelomocytes. Damage induced by leachate during a short, 2h exposure were small but noticeable, statistical analysis showed a significant (p <0.001) differences in such parameters as comet moment and tail intensity between the control probe, and the concentrations of ≥ 6.2%.

3

Grafowa metoda segmentacji obiektów w postaci skupisk na przykładzie obrazów kometowych

Bal A.

Pomiary Automatyka Kontrola

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2012

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R. 58, nr 4

313-315

PL

W pracy przedstawiono propozycję metody segmentacji obiektów będących skupiskami - przykładem takich obiektów są tzw. komety, które są wynikiem jednokomórkowej elektroforezy żelowej. Opracowana metoda działa dwuetapowo: etap 1. to segmentacja służąca wyznaczeniu elementów składowych należących do obiektów, etap 2 wykorzystuje minimalne drzewo rozpinające do określenia zbioru elementów tworzących poszczególne obiekty, obszar poszczególnych obiektów wyznaczany jest jako otoczka wypukła odpowiedniego drzewa rozpinającego.

EN

This paper deals with a problem of segmentation of aggregate objects, that is objects which are formed by a set of unconnected elements smaller than the object itself. Images of such a type of objects are very difficult for segmentation. An example of this type of objects are "comets" (Fig. 1, left column) from Single Cell Gel Electrophoresis images (also called comet assay images). In comet assay images the comet region is formed by unconnected fragments of DNA. Because of not satisfying results of comet segmentation with use of the standard methods, a new method for segmentation of such images was developed. The new method works in two stages. The first stage is the image segmentation-for comets the Bernsen binarization method (Eqs. (1) and (2)) with median filtering of the obtained results was chosen-the result of this stage is a set of comet elements ei which represent DNA fragments (Fig. 1, the 2nd column). In the second stage the minimum spanning trees Tp are created (Fig. 1, 3th column)-graph vertexes vi represent elements ei, and length dij of edge eij between vertexes vi and vj is equal to the closest distance between pixels of elements ei and ej-then for each connected tree Tp its convex hull which defines the region of comet Kp (Fig. 1, the 4th column) is created. In case of defects appearing in comet images, the incorrect region can be rejected e.g. by use of geometrical or photometrical features of the regions.

4

Genotoxic effects of 60Co gamma-rays on Chinese hamster ovary (CHO) cells

Dicu T., Brie I., Virag P., Fischer E., Perde M., Foriş V., Cernea V., Cosma C.

Nukleonika

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2008

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Vol. 53, No. 4

161-165

EN

The aim of the present study was to evaluate the cellular radiosensitivity and radiation-induced DNA damage and repair in Chinese hamster ovary (CHO) cells. Cell survival after irradiation was assessed using the clonogenic assay. The initial, radio-induced and residual DNA damage in Chinese hamster ovary (CHO) cells exposed to 60Co gamma-rays were determined using the alkaline comet assay. A linear-quadratic (LQ) survival curve was observed in CHO line. Data obtained by comet assay demonstrated a linear dose-response correlation in the range of tested doses (0.3-4 Gy). The process of DNA repair was modeled by exponential equation. In addition, we found a good correlation (R2 = 0.995) between clonogenic cell survival and radio-induced DNA damage.

5

alfa-Aminoalkylphosphonates Induced Apoptosis in Human Tumor Cell Lines

Drąg M.

Polish Journal of Chemistry

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2005

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Vol. 79 / nr 3

593-602

EN

Evaluation of the in vitro activity of the 1-amino-3-phenylpropanephosphonic acid and diphenyl 1-(N-benzyloxycarbonylamino)-1-(4-amidinophenyl)methanephosphonate hydrochloride toward acute, human Jurkat and A549 cell lines revealed that these compounds are potent inducers of apoptosis. Their potency to inhibit proliferation of tested tumor lines is similar to bestatin, a well-known inhibitor of aminopeptidases and strong inducer of apoptosis in the number of cancer cell. In this paper preliminary experimental details as well as the possible mechanism of action of alfa-aminoalkylphosphonates will be discussed.

6

Comparison of the effects of bleomycin and ionizing radiation in two sublines of murine lymphoma L5178Y

Kruszewski M., Zaim J., Grądzka I., Szumiel I.

Nukleonika

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2001

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Vol. 46, nr 3

81-86

EN

We compared the effects of bleomycin (BLM) and ionizing radiation on two sublines of murine lymphoma L5178Y (LY): LY-R, radiation resistant and LY-S, radiation sensitive. This radiosensitivity difference is related to the ability to rejoin DNA double strand breaks. LY-S cells were about two times more sensitive to BLM than LY-R, similarly as in the case of sensitivity to X rays. Since there was no difference in the P-glycoprotein-related drug transport system between the sublines, it could be expected that the enhanced sensitivity of LY-S cells to BLM was caused by the DNA repair defect. Growth disturbances in BLM treated cell populations were proportional to the lethal effect and their duration was observed until elimination of dead cells (3-6 days after 50 ěM BLM, 1 h at 37oC). There was no slow growth phase accompanied by normal viability, as previously described for X-irradiated LY-S cells. Initial DNA damage, estimated with the single cell gel electrophoresis method was linearly related to BLM dose in LY-S cells; in LY-R cells - in the low dose range (up to 10 ěM) - there was more damage than in LY-S cells, however, at higher doses the dose - effect curves became identical. The doseeffect relationship for ă rays was linear and identical in both cell sublines. DNA damage distribution in BLM treated cells was much less uniform as compared to that in irradiated cells and indicated the presence of cells with severely damaged DNA, a feature typical for BLM action in vitro.

7

Application of the DNA comet assay for detection of irradiated meat

Kruszewski M., Malec-Czechowska K., Dancewicz A. M., Iwaneńko T., Szot Z., Wojewódzka M.

Nukleonika

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1998

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Vol. 43, nr 2

147-160

EN

Radiation induces damage to the DNA. This damage (fragmentation) can be assessed in the irradiated food using Single Cell Gel Electrophoresis (SCGE), known as DNA comet assay. Fragmentation of DNA may also be caused by improper storage of meat and repeated freezing and thawing. This makes identification of irradiated meat by this assay not reliable enough. In order to know the scale of the processes imitating irradiation effects in DNA of the comets, their shape and lenghts were examined in both unirradiated and irradiated fresh meat (D = 1.5 or 3.0 kGy) stored at 4°C or frozen (-21°) up to 5 months. Comets formed upon SCGE were stained with DAPI or silver and examined in fluorescent or light microscope. They were divided arbitrarily into 4 classes. Comets of class IV were found quite often in fresh meat stored at 4°C. In meat samples that were irradiated and stored frozen, comets of class, I, II and III were observed. The negative comet test is univocal. Positive comet test, however, needs confirmation. The meat should be subjected to further analysis with other validated methods.

PL

Promieniowanie powoduje uszkodzenia DNA. Te uszkodzenia (fragmentację) można ocenić w napromieniowanej żywności stosując elektroforezę w żelu pojedynczej komórki, zwaną także testem kometowym. Fragmentację DNA w mięsie mogą także wywoływać: nieprawidłowe przechowywanie mięsa oraz powtarzane zamrażanie i rozmnażanie. Czyni to identyfikację napromieniowania mięsa mniej wiarygodną. W celu poznania procesów imitujących napromieniowanie, tj. powodujących powstawanie kometek DNA, oceniano ich kształt i długość w mięsie nie napromieniowanym i napromieniowanym dawką 1.5 lub 3.0 kGy przechowywanym w 40C lub w stanie zamrożenia do 5 miesięcy. Otrzymane kometki DNA barwiono barwnikiem fluorescencyjnym DAPI lub srebrem i badano w mikroskopie fluorescencyjnym lub zwykłym. Kometki podzielono na 4 klasy. Kometki IV klasy znajdowano często w mięsie przechowywanym w 40C. W próbkach mięsa napromieniowanego i przechowywanego w stanie zamrożenia obserwowano kometki klasy l, II i III. Negatywny test kometowy jest jednoznaczny. Test dodatni wymaga potwierdzenia przez zastosowanie innych metod dających miarodajne wyniki.