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Leukemia represents a serious public health concern as the incidence is increasing worldwide. In this study we aimed to describe the epidemiological profile of acute lymphoblastic (ALL) and myeloid (AML) leukemia, identify disease clusters and find association with possible risk factors.Data on leukemia cases were provided by the National Institute of Health of the Republic of Armenia for the period of 2012-2018. Age-standardized incidence rate was calculated using Segi World Population. SaTScan purely spatial analysis was applied to find leukemia clusters. To find association between leukemia and agricultural and mining activities and demographic data Poisson regression model was used.During the studied period 259 new cases of ALL and 478 AML were recorded. The age-standardized incidence rate was 1.5 and 1.9 per 100,000 inhabitants with male to female ratio of 0.97 and 1.1 for ALL and AML, respectively. No significant changes in ALL or AML incidence trends were found. For ALL significant cluster encompassing Shirak, Lori, Tavush and Armavir provinces of Armenia was identified, while Kotayk and Ararat was provinces with the highest incidence of AML. We found significant positive association of ALL with crop density, while no elevated risk estimates were found between AML and exposure variables.Altogether, our results suggested that acute leukemias incidence in Armenia follows the pattern described for developing countries.

Purpose To describe the contribution of women scientists in the development of biomedical studies conducted on research facilities based on the ultrashort pulsed laser technologies in Armenia. Conclusion Given the opportunities provided by the ultrashort pulsed laser driven two-photon microscopy and electron beam linac facilities at CANDLE Synchrotron Research Institute, the Armenian women scientists initiated and conducted interdisciplinary research to understand of the biomedical effects of ultrashort pulsed electron beam irradiation, as well as to experience and apply the advantages of the two-photon microscopy in their fields of research. Women scientists had a crucial role and unique impact in the development of ultrashort pulsed laser technology-based biomedical studies in Armenia.

Rapidly evolving laser technologies have led to the development of laser-generated particle accelerators as an alternative to conventional facilities. However, the radiobiological characteristics need to be determined to enhance their applications in biology and medicine. In this study, the radiobiological effects of ultrashort pulsed electron beam (UPEB) and X-ray radiation in human lung fibroblasts (MRC-5 cell line) exposed to doses of 0.1, 0.5, and 1 Gy are compared. The changes of &gamma, H2AX foci number as a marker of DNA double-strand breaks (DSBs) were analyzed. In addition, the micronuclei induction and cell death via apoptosis were studied. We found that the biological action of UPEB-radiation compared to X-rays was characterized by significantly slower &gamma, H2AX foci elimination (with a dose of 1 Gy) and strong apoptosis induction (with doses of 0.5 and 1.0 Gy), accompanied by a slight increase in micronuclei formation (dose of 1 Gy). Our data suggest that UPEB radiation produces more complex DNA damage than X-ray radiation, leading to cell death rather than cytogenetic disturbance.

Recently, it was reported that ochratoxin A (OTA) mycotoxin, produced by a number of Aspergillus and Penicillium fungal species, may cause neuropsychological impairment or mental and emotional disorders but the mechanism of neurotoxicity remains unknown. Adverse effects of OTA in human (SHSY5Y) and mouse (HT22) neuronal cell lines were studied in vitro. OTA was found to be non-cytotoxic in both cell lines at concentrations 2.5–30 μmol/l, which are above the levels reported for human and animal plasma. OTA led to slightly elevated chromosomal instability in HT22 cells at concentrations of 15–30 μmol/l after 48 h, while in SHSY5Y cells, no evidence for genotoxic effects was observed at concentrations of 2.5–30 μmol/l. OTA treatment at 10 μmol/l resulted in elevated levels of unmethylated cytosines in CpG dinucleotides (up to 1.4-fold), elevated levels of intracellular reactive oxygen species (up to 1.6-fold), and in elevated levels of oxidized DNA purines (up to 2.2-fold) in both cell lines. Detected global DNA hypomethylation and oxidative stress were found to be reversible in 96 h and 24–72 h, respectively. In general, the observed pattern of OTA-induced effects in both cell lines was similar, but HT22 cells exhibited higher sensitivity, as well as better repair capacity in response to OTA toxicity. In conclusion, the results suggest that oxidative stress and epigenetic changes are directly involved in OTA-induced neurotoxicity, while cytotoxicity and genotoxicity cannot be considered as primary cause of toxicity in neuronal cells in vitro.

Laser-driven accelerators allow to generate ultrashort (from femto- to picoseconds) high peak dose-rate (up to tens of GGy/s) accelerated particle beams. However, the radiobiological effects of ultrashort pulsed irradiation are still poorly studied. The aim of this work was to compare the formation and elimination of γH2AX and 53BP1 foci (well known markers for DNA double-strand breaks (DSBs)) in Hela cells exposed to ultrashort pulsed electron beams generated by Advanced Research Electron Accelerator Laboratory (AREAL) accelerator (electron energy 3.6 MeV, pulse duration 450 fs, pulse repetition rates 2 or 20 Hz) and quasi-continuous radiation generated by Varian accelerator (electron energy 4 MeV) at doses of 250–1000 mGy. Additionally, a study on the dose–response relationships of changes in the number of residual γH2AX foci in HeLa and A549 cells 24 h after irradiation at doses of 500–10,000 mGy were performed. We found no statistically significant differences in γH2AX and 53BP1 foci yields at 1 h after exposure to 2 Hz ultrashort pulse vs. quasi-continuous radiations. In contrast, 20 Hz ultrashort pulse irradiation resulted in 1.27-fold higher foci yields as compared to the quasi-continuous one. After 24 h of pulse irradiation at doses of 500–10,000 mGy the number of residual γH2AX foci in Hela and A549 cells was 1.7–2.9 times higher compared to that of quasi-continuous irradiation. Overall, the obtained results suggest the slower repair rate for DSBs induced by ultrashort pulse irradiation in comparison to DSBs induced by quasi-continuous irradiation.