Normal and Cut-Off Values of the Cytokinesis-Block Micronucleus Assay on Peripheral Blood Lymphocytes in the Croatian General Population

Mikronukleus (MN) test na limfocitima periferne krvi jedna je od najvažnijih metoda koje se primjenjuju u citogenetičkom nadzoru. Osnovni preduvjet za primjenu nekog testa u svrhu nadzora profesionalno izloženih populacija jest poznavanje normalnih vrijednosti promatranoga biološkog pokazatelja (biomarkera) u kontrolnoj populaciji. Baze podataka na razini opće populacije moraju se redovito obnavljati novim podacima. Cilj ovog istraživanja bio je utvrditi normalne i granične vrijednosti MN-testa na limfocitima periferne krvi 200 zdravih ispitanika obaju spolova iz opće populacije Republike Hrvatske te ispitati koji čimbenici pridonose spontanom nastanku MN. Na razini istražene populacije utvrđeno je prosječno (6,90±3,32) MN (medijan 7 MN), dok je raspon pojedinačnih vrijednosti iznosio 0 do 18 MN u 1000 binuklearnih stanica. Gornja granična vrijednost dobivena izračunavanjem 95. percentila za cjelokupnu promatranu populaciju iznosi 12,5 MN na 1000 limfocita. Utvrđeno je da na spontani nastanak MN utječu spol, dob i navika pušenja. Žene u prosjeku imaju više vrijednosti svih parametara MN-testa od muškaraca, a u njih je bio i naglašeniji porast vrijednosti citogenetičkog nalaza zbog navike pušenja. Kako su literaturni podaci o utjecaju pušenja cigareta na nastanak MN kontradiktorni, planiran je nastavak istraživanja radi razjašnjavanja utjecaja dnevno utrošenog broja cigareta i ukupnog trajanja pušačkog staža na vrijednosti parametara MN-testa. Usporedba rezultata s literaturnim podacima potvrdila je da su dobivene vrijednosti u skladu s vrijednostima MN-testa zabilježenim na općoj populaciji u drugim svjetskim laboratorijima. Normalne i granične vrijednosti MN-testa utvrđene u ovome istraživanju poslužit će kao osnova za usporedbu i tumačenje nalaza MN-testa u ispitanika izloženih populacija te daljnju nadogradnju laboratorijske baze podataka.The cytokinesis-block micronucleus (CBMN) assay on peripheral blood lymphocytes is one of the most important methods employed in cytogenetic biomonitoring. For the purposes of biological dosimetry, it is important to kno the spontaneous frequency of a biomarker and its normal values in general population. These values are used for population databases, which should be updated regularly. In this study, MN levels were investigated in cytokinesis-blocked lymphocytes of 200 healthy male and female blood donors selected at random from the general population of Croatia. The aim was to assess the variability and determine possible infl uences of external and/or internal factors on the background levels of MN and to establish the cut-off value for the CBMN assay. The background frequency of MN was (6.90±3.32) MN (median 7 MN) and the range was 0 to 18 MN per 1000 binuclear lymphocytes. The cut-off value, which corresponds to 95th percentile of the distribution of 200 individual values, was 12.5 MN. Spontaneous formation of MN was infl uenced by sex, age, and smoking. Women had higher MN levels than men. However, only age and smoking signifi cantly increased the values of all parameters evaluated by the CBMN assay. Since the existing literature data on smoking-related formation of MN are contradictory, we will continue these investigations to resolve how the number of cigarettes smoked per day and the duration of smoking in years infl uence the results of the CBMN assay. Our results are consistent with the background MN frequencies reported by other cytogenetic laboratories worldwide. Normal and cut-off values estimated in this study will be used to update the current general population data and as reference for occupationally or accidental exposure

The psychological science accelerator’s COVID-19 rapid-response dataset

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data

Antineoplastic Drugs as a Potential Risk Factor in Occupational Settings: Mechanisms of Action at the Cell Level, Genotoxic Effects, and Their Detection Using Different Biomarkers

U članku je prikazana osnovna podjela antineoplastičnih lijekova prema mehanizmima djelovanja na razini stanice. Objašnjeni su mehanizmi genotoksičnosti najvažnijih vrsta lijekova koji se primjenjuju u okviru uobičajenih protokola za liječenje zloćudnih novotvorina. Navedena je važeća klasifi kacija antineoplastika prema kancerogenom potencijalu, podaci o mutagenom potencijalu te je prikazana njihova podjela u skladu s anatomsko-terapijsko-kemijskim sustavom klasifi kacije. Sustavno su prikazani najvažniji rezultati svjetskih i hrvatskih istraživanja na populacijama radnika izloženih antineoplasticima, provedenih u razdoblju 1980.-2009. s pomoću četiri najčešće primjenjivane metode: analize izmjena sestrinskih kromatida, analize kromosomskih aberacija, mikronukleus-testa i komet-testa. Objašnjena su osnovna načela navedenih metoda te raspravljene njihove prednosti i nedostaci. Biološki pokazatelji daju važne podatke o individualnoj osjetljivosti profesionalno izloženih ispitanika koji mogu poslužiti unaprjeđenju postojećih uvjeta rada i upravljanju rizicima pri izloženosti genotoksičnim agensima. Na osnovi prednosti i nedostataka citogenetičkih metoda zaključeno je da je mikronukleus-test, koji podjednako uspješno dokazuje klastogene i aneugene učinke, jedna od najboljih metoda dostupnih za otkrivanje štetnih djelovanja antineoplastičnih lijekova koji su u aktivnoj primjeni.This article brings an overview of the mechanisms of action of antineoplastic drugs used in the clinical setting. It also describes the genotoxic potentials of the most important classes of antineoplastic drugs involved in standard chemotherapy protocols. Classifi cation of antineoplastic drugs according to the IARC monographs on the evaluation of carcinogenic risks to humans is accompanied by data on their mutagenicity and the most recent updates in the Anatomical Therapeutic Chemical (ATC) Classifi cation System. We report the main fi ndings of biomonitoring studies that were conducted in exposed healthcare workers all over the world between 1980 and 2009 using four biomarkers: sister chromatid exchanges, chromosome aberrations, micronuclei. and the comet assay. The methods are briefl y explained and their advantages and disadvantages discussed. Biomarkers provide important information on individual genome sensitivity, which eventually might help to improve current working practices and to manage the risks related with exposure to genotoxic agents. Taking into consideration all known advantages and drawbacks of the existing cytogenetic methods, the micronucleus assay, which is able to detect both clastogenic and aneugenic action, is the most suitable biomarker for assessing harmful effects of antineoplastic drugs currently used in health care

The Psychological Science Accelerator’s COVID-19 rapid-response dataset

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data

Correlation between micronuclei frequency in peripheral blood lymphocytes and retention of 131-I in thyroid cancer patients

Differentiated thyroid cancers (DTCs) derive from thyroid follicular cells and include papillary and follicular cancers. In patients with DTCs, the initial treatment includes thyroidectomy and radioactive iodine (131-I) therapy. The objective of this study was to examine whether the intensity of DNA damage in peripheral blood lymphocytes (PBLs) of DTC patients depends on the amount of 131-I retained in the selected regions of interest (thyroid and abdominal region) as well as in the whole-body 72 hours after therapy. In addition, the possible influence of other factors that may affect micronuclei (MN) frequency, such as age, gender, smoking habits, and histological type of tumour was analyzed. The study population consisted of 22 DTC patients and 20 healthy donors. Data on the distribution of 131-I were obtained from the whole-body scans. MN frequency and cytokinesis-block proliferation index (CBPI) were measured using cytokinesis-block micronucleus assay. 131-I therapy significantly increased the MN frequency (19.50 ± 6.90 vs. 27.10 ± 19.50 MN) and significantly decreased the CBPI (1.52 ± 0.20 vs. 1.38 ± 0.17) in patients' lymphocytes. There was a clear correlation between the increased MN frequency and 131-I accumulation in the thyroid region in patients without metastases. The MN values did not differ in relation to the factors that could affect MN, such as age, gender, smoking habits, and histological type of tumour. In conclusion, the MN frequency in PBLs of DTC patients without metastases depends on the accumulation of 131-I in the thyroid region and does not depend on the other factors examined. © 2013 Tohoku University Medical Press

Radioiodine therapy accelerates apoptosis in peripheral blood lymphocytes of patients with differentiated thyroid cancer

Both apoptosis and micronuclei formation reflect cytogenetic damage in cells and could contribute to cell homeostasis. The aim of this study was to evaluate apoptosis in peripheral blood lymphocytes (PBLs) of patients with differentiated thyroid cancer (DTC) before and after 131-iodine (131-I)-therapy and its correlation with micronuclei (MN) frequency. The study population included 18 DTC patients and 18 healthy donors. Apoptotic cells were detected using the Annexin V-FITC/7-AAD kit and MN frequency by cytokinesis-block MN assay. The difference between early apoptosis in PBLs of DTC patients before therapy and controls (9.88 ± 4.99% vs. 6.64 ± 2.07%, p = 0.003) was significant, as well as between early apoptosis in PBLs of DTC patients before and after 131-I-therapy (9.88 ± 4.99% vs. 13.53 ± 6.57%, p = 0.008). The MN frequency and early apoptosis in PBLs of DTC patients was positively correlated before (r = 0.540, p = 0.021) and after 131-I-therapy (r = 0.585, p = 0.014). Thyroid cancer patients had a significantly increased early apoptosis in PBLs, which further increased after 131-I-therapy in association with MN frequency

Influence of GSTT1 and GSTM1 null genotypes on differentiated thyroid cancer risk and baseline and radioiodine induced cytogenetic damage in peripheral blood lymphocytes of patients

As it is known that genetic polymorphisms of glutathione S-transferases (GST) have been associated with a variety of human diseases including cancer, we have analyzed the impact of GSTT1 and GSTM1 null genotypes on the risk of development of differentiated thyroid cancer (DTC) and cytogenetic changes in peripheral blood lymphocytes of DTC patients before and after radioiodine therapy. The polymorphism of GSTT1 and GSTM1 genes were genotyped using multiplex polymerase chain reaction (PCR) and cytokinesis - block micronucleus (MN) assay to assess cytogenetic changes. GSTT1 and GSTM1 null were predominantly found in patients, but statistical significance was observed only for GSTT1 null. The null genotypes increased risk of development of DTC; GSTT1 null a 4.5 times (p < 0.05), GSTM1 null about 3 times but on the border of statistical significance (p = 0.057), while combination of dual null genotypes almost 7 times (p < 0.05) increased risk. No significant effects of the null genotypes as well as their interactions with potential modifiers of MN (diagnose, age, gender and smoking habits) were observed on both baseline and radioiodine-induced values of MN and cytokinesis block proliferation index (CBPI) in DTC patients. Results suggest that both GSTT1 and GSTM1 null genotypes increased risk for DTC but to a greater extent GSTT1 null. Null genotypes of GSTT1 and GSTM1 did not have potential to influence baseline and radioiodine-induced values of MN and CBPI, so that absence of T1 and M1 isoenzymes did not cause increased mutagen sensitivity of PBLs of DTC patients

Ethyl acetate extracts of two Artemisia species: Analyses of phenolic profile and anticancer activities against SW-480 colon cancer cells

© The Author(s) 2019 Article reuse guidelines: sagepub.com/journals-permissions Because Artemisia vulgaris L. and Artemisia alba Turra are traditional medicinal plants used for the treatment of different diseases, we evaluated the cytotoxic/apoptotic activity of ethyl acetate extracts from these natural products against human colon cancer cells SW-480. The extracts contained a large amount of the total polyphenols and flavonoids. The phenolic profile showed the presence of phenolic acids (gallic, p-coumaric, vanillic, and ferulic acids) and flavonoids (rutin, myricetin, luteolin, quercetin, and apigenin). 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay indicated that antiproliferative activities of both A. vulgaris and A. alba extracts increased with the extension of time exposure, with decreasing IC50 values. Mitomycin C (MMC) alone had antiproliferative activity, but in combination with plant extracts caused stronger effect with lower IC50 values. Flow cytometry analyses showed that A. alba extract induced higher percentage of SW-480 cells in the early stage of apoptosis (33.5 ± 1.6 vs 0.7 ± 0.1, P < 0.05), whereas the A. vulgaris extract significantly increased the percentage of cells in necrosis (82.4 ± 5.0 vs 53.9 ± 2.3, P < 0.05). In conclusion, A. alba extract can be considered a potential source of bioactive components with anticancer activity or be used as a dietary food supplement or supplement to chemotherapy due to its synergistic effect with the MMC

Apoptosis and genome instability in children with autoimmune diseases

© 2018 The Author(s). As apoptosis and genome instability in children with autoimmune diseases (AIDs) are insufficiently investigated, we aimed to analyse them in peripheral blood lymphocytes (PBLs) of children and adolescents with Hashimoto's thyroiditis (HT), Graves' disease (GD) and type 1 diabetes mellitus (T1DM), including possible factors that could affect their occurrence. The study population included 24 patients and 19 healthy controls. Apoptotic cells were detected using an Annexin V-FITC/7-AAD kit. Genome instability was measured as micronuclei (MNs) frequency using the cytokinesis-block MN assay. In addition, comet assay was performed for determination of genome instability as genome damage index (GDI) in new subpopulation of patients with T1DM. The percentage of apoptotic PBLs in patients with AID was significantly lower than in control subjects. There was a positive correlation between thyroid-stimulating homone (TSH) concentration and the proportion of cells in late stage apoptosis in patients with autoimmune thyroid diseases (AITDs). The MN frequency in patients was significantly higher than in controls. Individuals with HT or T1DM had a significantly higher MN frequency than those with GD. Similarly, the value of GDI in patients with T1DM was significantly higher than in controls. The level of apoptosis was positively correlated with MN frequency as well as with GDI in patients with AID. In conclusion, children with AITD (HT and GD) and T1DM have a significantly lower level of apoptosis in PBLs and significantly higher MN frequency as GDI than healthy subjects. Apoptosis and the level of genome instability in these patients with AID are positively correlated