Percentage Of Aberrant Cells Research Articles

Assessment of the Mutagenic and Cytotoxic Ability of Azanza Garckeana (F.Hoffm), Using Allium Cepa (L) Assay

The study on the assessment of the mutagenic and cytotoxic ability of Azanza garckeana leaf and fruit extracts on the root tip of Allium cepa was evaluated; aqueous leaf and fruit extract of A. garckeana were collected and dried, and pounded into powder. For the root growth inhibition and cytological analysis, four concentrations of each extract, viz: 5g,10g, 15g, and 20g, including positive and negative control, were considered, and the result was determined for each extract using a graph to indicate the maximum and minimum EC50 (Effective concentration). The EC ranged from 10 g/ml with a root length of 3 cm for A. garckeana leaf extracts, 10g/ml with a root length of 2.5 cm for A. garckeana fruits extracts, A range of chromosomal aberrations such as polyploidy, dissolution, vagrant metaphase, binucleate, laggard, nuclear lesion, fragmentation, chromosome gap, anaphase bridge, micronuclei, unequal separation, were observed in all the plant’s extracts. Statistically, the chromosomal aberrations observed in the root tip cells of A. cepa treated with the leaf extracts of A. garckeana shows that 10g is statistically significantly different from 5g (P = 0.026) and negative control, 15g is significantly different from 5g (P = 0.000) and 10g (P = 0.026). However, as the concentration increased to 20g, there was a significant difference in the percentage of aberrations from 5g (P =0.0000) to 10g (P = 0.005), but not significantly different from 15g (P =0.0553). Whereas fruit extract shows that 10g is higher than 5g but has no statistical significance (P =0.101). 15g is significantly different from 5g (P =0.101) but not significantly different from 10g (P =0.055), 20g (P =0.331), and positive control (P =0.845). As the concentrations of the plant extracts increased to 10%, 15%, and 20%, there was a progressive increase in the percentage of aberrant cells and a decrease in the number of dividing cells, suggesting that low concentrations of A. garckeana extracts should be used in traditional medicine production.

In vivo cytogenotoxicity testing of isotretinoin by the micronucleus assay in the blood of male Sprague-Dawley rats Isotretinoin is cytotoxic and genotoxic

Isotretinoin (ISO), one of vitamin A-derived retinoids, is comparatively the most widely prescribed drug in acne vulgaris pathogenesis. Despite its excellent therapeutic success, the systemic use of this drug showed undesirable serious side effects such as teratogenesis, oxidative stress, and genotoxicity. The uses of retinoids in cancer therapy are limited due to severe adverse reactions. This has led the scientific community to ask for further studies qualifying ISO features and comparing their efficacy and safety. The purpose of this study was to evaluate the cytogenotoxicity of multiple oral doses (5, 10, 15, and 20 mg/kg, daily for seven consecutive days) of ISO in male Sprague-Dawley rats. The micronucleus assay was used to investigate genotoxicity biomarkers such as the percentage of micronucleated polychromatic erythrocytes (%MNPCEs) and the percentage of aberrant cells (%Abc). Another goal was to test the cytotoxicity of the drug by measuring the ratio between PCEs and normochromatic erythrocytes (NCEs) (PCEs/NCEs). In comparison with the control, the three cytogenetic endpoints: %MNPCEs, P/N, and %Abc significantly (P ≤ 0.0017) dose-dependent increase. This suggested genotoxicity and cytotoxicity of the tested ISO doses. Therefore, the therapeutic uses of ISO should be restricted to a very narrow range border. Further studies are needed to shed more light on the safety profile of ISO therapy.

Cyto-genotoxic potential of petroleum refinery wastewater mixed with domestic sewage used for irrigation of food crops in the vicinity of an oil refinery

Petroleum refinery wastewater combined with domestic sewage were collected from the open channel in the vicinity of Mathura oil refinery, UP (India) and analysed by inductively coupled plasma optical emission spectrometry (ICP-OES) and gas chromatography-mass spectrometry (GC-MS) for elemental analysis and organic pollutants, respectively. Several potentially toxic and non-toxic elements were found to be present in the wastewater samples. GC-MS analysis revealed the presence of several organic contaminants including pesticides. Wastewater samples were extracted using amberlite XAD4/8 resins and liquid-liquid extraction procedures using different organic solvents. The extracts were tested for their cyto-genotoxic potential using bacterial (Salmonella mutagenicity test, E. coli K-12 DNA repair defective mutants, Bacteriophage λ assay) and plant (Vigna mungo phytotoxicity test, Allium cepa chromosomal aberration assay) systems. A significant increase was observed in the number of revertants of TA97a, TA98 and TA100 strains with the test samples and XAD concentrated samples were found to be more mutagenic than liquid-liquid extracts. Colony forming units (CFUs) of DNA repair defective mutants of E. coli K-12 recA, lexA and polA declined significantly as compared to their isogenic wild-type counterparts with the test samples. Significant reduction in plaque forming units (PFUs) of bacteriophage λ was also found on treatment with the solvent extracts. Presence of several toxic pollutants in the wastewater apply prohibitive action on the seed germination process. Germination rate of Vigna mungo seeds as well as radicle and plumule lengths were found to be affected when treated with different concentration of wastewater as compared to control. Present study also indicated concentration dependent reduction in mitotic index of A. cepa i.e., 16.38% at 5% and 9.74% at 100% wastewater and percentage of aberrant cells were highest at 100% effluent. Present findings indicated that mutagenicity/genotoxicity of wastewater is due to the mixture of genotoxins; poses serious hazards to the receiving waterbodies which require continuous monitoring and remedial measures for their improvement.

CTAB Surfactant Assisted and High pH Nano-Formulations of CuO Nanoparticles Pose Greater Cytotoxic and Genotoxic Effects

Toxicity of synthesized nanoparticles is the area of concern to all the researchers due to their possible health implications. Here we synthesized copper oxide nanoparticles (CuO NPs) without surfactant at pH value of 2, 7, 10 and with cetyletrimethylammoniumbromide (CTAB) surfactant at pH 7. Synthesized nanoparticles were characterized for various structural parameters including crystallite size, lattice parameters, strain, phase analysis using X-ray diffraction analysis, and morphological aspects have been analyzed using FESEM and HRTEM imaging. All the four nano-formulations were analyzed for their toxic potential using Allium cepa L. at three different concentrations (0.1, 0.01 and 0.001 g/100 ml). Cytological and genetic parameters including mitotic index, mitotic inhibition, aberrant cells, binucleated cells, micronucleated cells, chromosomal bridges, fragmentation, stickiness, laggards, vagrants, c-mitosis and disturbed spindle were analyzed. Our results revealed a dose dependent increase in cytotoxic parameters including decreased total dividing cells, mitotic index, and increased mitotic inhibition. Genotoxic parameters also increased at higher treatment concentrations including chromosomal aberrations and percent aberrant cells. The pH value at the time of particle synthesis has significant influence on the crystallite size and agglomeration as assessed by XRD, FESEM and HRTEM analysis. The NPs synthesized at pH 2 and 10 were found to be of smaller size and posed more toxic effects as compared to particles synthesized at neutral pH. On the other hand, CTAB assisted CuO NPs synthesized at pH 7 revealed even smaller crystallite sizes and thus boost the toxicity in all the parameters as compared to NPs synthesized without CTAB. The present study suggested an increase in toxic parameters of synthesized CuO NPs with respect to crystallite size which is pH dependent. Addition of CTAB at pH 7 decreased the crystallite as well as particle size and enhanced the toxic potential. Further studies are recommended to analyze the effect of surfactant addition in toxicological studies on CuO NPs.

Evaluation of cyclophosphamide-induced genotoxicity and cytotoxicity in cultured human lymphocytes

Aim: The present study was aimed to examine and evaluate the genotoxicity and cytotoxicity induced by different doses of cyclophosphamide (CP) in normal healthy cultured human peripheral blood lymphocytes. Materials and Methods: Genotoxicity and cytotoxicity was evaluated through mitotic index (MI), chromosomal aberrations, micronuclei frequency, and colony formation assay (plating efficiency [PE] and survival fraction), respectively. Results: It has been observed that CP (1, 2.5, and 5 μg/ml)) induced a dose-dependent increase in chromosomal aberrations and micronuclei frequencies in cultured human peripheral blood lymphocyte as compared to normal. A significant increase was observed in the percentage of aberrant cells and dicentrics/exchanges at 1 and 2.5 μg/ml CP and aberrant cells, breaks, fragments, and dicentrics/exchanges at 5/μg/ml CP. A dose-dependent decrease in values of MI and nuclear division index was also observed in CP-treated group. The frequency of micronuclei in binucleated cells showed a dose-dependent increase. In colony formation assay, PE and surviving fraction values showed significant (P

Antimutagenic and anticlastogenic effects of Turkish Black Tea on TA98 and TA100 strains of Salmonella typhimurium (in vitro) and mice (in vivo)

Context: Black tea has been reported to have significant antimutagenic and anticarcinogenic properties associated with its polyphenols theaflavins (TF) and thearubigins (TR). Similarly, Turkish black tea (TBT) also contains a considerable amount of TF and TR. Objective: This study investigated the mutagenic, antimutagenic and anticlastogenic properties of TBT. Materials and methods: The mutagenic and antimutagenic effects of TBT (10 to 40000 μg/plate) were investigated in vitro on Salmonella strains TA98 and TA100 with and without S9 fraction. Anticlastogenic effect was studied at concentrations of 300–1200 mg/kg TBT extract by chromosomal aberrations (CA) assay from bone marrow of mice. Results: The results of this study did not reveal any mutagenic properties of TBT. On the contrary, TBT extract exhibited antimutagenic activity at >1000 μg/plate concentrations in TA98 strain with and without S9 activation (40% inhibition with S9 and 27% without S9). In TA100 strain, the antimutagenic activity was observed at >20,000 μg/plate TBT extracts without S9 activation (28% inhibition) and at >1000 μg/plate with S9 activation (59% inhibition). A significant decrease in the percentage of aberrant cells (12.33% ± 1.27) was observed in dimethylbenz(a)anthracene (DMBA) plus highest concentration (1200 mg/kg) of TBT extract-treated group when compared to only DMBA-treated group (17.00% ± 2.28). Discussion and conclusion: Results indicated that TBT can be considered as genotoxically safe, because it did not exert any mutagenic and clastogenic effects. As a result, TBT exhibited antimutagenic effects more apparently after metabolic activation in bacterial test system and had an anticlastogenic effect in mice.

Mapping the factors affecting the frequency and types of micronuclei in an elderly population from Southern Bohemia

The micronucleus assay is one of the most common methods used to assess chromosomal damage (losses or breaks) in human peripheral blood lymphocytes (PBL) in genetic toxicology. Most studies have focused on analyzing total micronuclei (MN), but identifying the content of MN can provide more detailed information. The main aim of this study was to map the factors affecting the frequency and types of micronuclei in binucleated cells (BNC) in elderly population. Fluorescence in situ hybridization using Human Pan Centromeric Chromosome Paint was used to identify centromere positive (CEN+) or centromere negative (CEN-) MN. A group of 95 men from Southern Bohemia, Czech Republic (average age 68.0±6.8 years) was followed repeatedly, in spring and fall 2014. The study participants were former workers of the uranium plant “MAPE Mydlovary” (processing uranium ore from 1962 to 1991), and controls. The general profile of individual types of MN, and the effect of the season, former uranium exposure, age, smoking status, weight, and X-ray examination on the level and type of MN were analyzed. The results of this study showed: (i) a stable profile of BNC with MN based on the number of MN during two seasons; (ii) an increase of the number of CEN+ MN from spring to fall; (iii) a lower frequency of the total MN in the exposed group than in controls with a significant difference in the percentage of aberrant cells (%AB.C.) in the fall; (iv) no clear effect of age, smoking and BMI on DNA damage in this group; (v) lower DNA damage levels in former uranium workers who received X-ray examination later in life. In summary, the results indicate a trend of seasonal changes of individual types of MN and suggest that former exposure can have a protective effect on the level of DNA damage in case of future exposure.

29 - Whole Genome SNP Array Improves Diagnosis and Therapy in Pediatric Brain Tumors

can be extremely useful information when proceeding with a full chromosomal copy number analysis of a sample. As the sample is evaluated, absolute copy number (versus relative copy number) is preferred for final reporting. The problem in general is extremely difficult if not impossible using data just from SNP arrays or NGS. An algorithm to estimate percent aberrant cells from a normal population was devised using B-allele frequency estimations derived from either SNP array or next generation sequencing results. This approach includes an automated calculation per copy number event for the percentage of cells that are aberrant to help distinguish mosaicism among the full sample population. Additionally, along with the type of copy number alteration (i.e. gain, loss), an estimate for absolute copy number will be reported for each event, if such estimation is possible. This tool was tested on a series of cancer samples with known aberrations. Estimation of percent aberrant cells and absolute copy number was possible for most regions of copy number alteration. Exceptions were limited to highly complex samples with mixed mosaicism.

Genotoxicity and cytotoxicity of Aloysia polystachia: an in vivo study in rabbits

In the search of new compounds useful for the treatment of neurological disorders, medicinal plant research has progressed widely in the last decade, particularly because of the hypothesis that natural extracts possess a low or absent toxicity. Aloysia polystachia (Griseb.) Moldenke belonging to the family of Verbenaceae has been used in the traditional medicine for a variety of indications and as a sedative. Recently, some evidence reported that it exhibits some antidepressant- and anxiolytic-like effects involving the modulation of GABA system in preclinical studies in mice (1). However no investigations have been performed on its (geno)toxicity in long-term studies as it would be required for its use in neurological pathologies. In this study, we investigated the genotoxic potential of a water soluble extract of Aloysia polystachia leaves, administered orally every day for 90 days to 20 New Zealand white rabbits homogeneous for weight and age. Subjects were divided into four groups: the control group, and three experimental groups fed with a diet supplemented with 1g/kg; 1.5 g/kg and 2g/kg of Aloysia Polystachia, then peripheral blood was drawn from the vein auricularis marginalis before and after 45 and 90 days of treatment. Cytogenetic analysis was performed on each subject at each time point and chromosome aberrations (structural and numerical) and mitotic index were used as a measure of DNA damage and cytotoxicity (2). Results indicated that Aloysia polystachia extract induces a significant increase in the percentage of aberrant cells as well as in the aberration frequency (mainly chromatid breaks and fragments) associated with a decreasing trend of the mitotic index. The DNA damage was particularly higher after the first 45 days of treatment whereas it remains significantly high but almost unvaried until the end of the treatment. These data suggest that Aloysia polystachia extract has genotoxic and cytotoxic activity, even though further investigations are required to assess which compound of the extract could be responsible for the observed effects.

Frequent induction of chromosomal aberrations in in vivo skin fibroblasts after allogeneic stem cell transplantation: hints to chromosomal instability after irradiation.

BackgroundTotal body irradiation (TBI) has been part of standard conditioning regimens before allogeneic stem cell transplantation for many years. Its effect on normal tissue in these patients has not been studied extensively.MethodWe studied the in vivo cytogenetic effects of TBI and high-dose chemotherapy on skin fibroblasts from 35 allogeneic stem cell transplantation (SCT) patients. Biopsies were obtained prospectively (n = 18 patients) before, 3 and 12 months after allogeneic SCT and retrospectively (n = 17 patients) 23–65 months after SCT for G-banded chromosome analysis.ResultsChromosomal aberrations were detected in 2/18 patients (11 %) before allogeneic SCT, in 12/13 patients (92 %) after 3 months, in all patients after 12 months and in all patients in the retrospective group after allogeneic SCT. The percentage of aberrant cells was significantly higher at all times after allogeneic SCT compared to baseline analysis. Reciprocal translocations were the most common aberrations, but all other types of stable, structural chromosomal aberrations were also observed. Clonal aberrations were observed, but only in three cases they were detected in independently cultured flasks. A tendency to non-random clustering throughout the genome was observed. The percentage of aberrant cells was not different between patients with and without secondary malignancies in this study group.ConclusionHigh-dose chemotherapy and TBI leads to severe chromosomal damage in skin fibroblasts of patients after SCT. Our long-term data suggest that this damage increases with time, possibly due to in vivo radiation-induced chromosomal instability.

Assessing Tumor Percentage: A Possible Solution in Evaluating HER2 Copy Number (HER2CN) Data Generated by Molecular Inversion Probe (MIP) Technology on Formalin-Fixed Paraffin-Embedded (FFPE) Sections of Breast Cancer (BC) With Low Tumor Cellularity

MIP technology has successfully produced quantitative HER2 copy number (HER2CN) data. Studies have shown high concordance between this emerging technology and conventional methods such as fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). OncoScan, the device behind MIP technology, appraises tumor percentage in the form of percent aberrant cells (%AC). However, inability to assess tumor heterogeneity, extensive stroma within the tumor, and prominent in situ …

Impact of sodium arsenite on chromosomal aberrations with respect to polymorphisms of detoxification and DNA repair genes.

Arsenic compounds can increase production of reactive oxygen species. Reactive oxygen species can induce double-strand breaks in DNA, which is a cause of chromosome aberrations (CAs). This study was conducted to determine the association between arsenic exposure and polymorphisms of genes involved in detoxification (glutathione S-transferase T1 [GSTT1], glutathione S-transferase M1 [GSTM1], glutathione S-transferase O2 [GSTO2], catalase [CAT], and NAD(P)H quinone oxidoreductase1 [NQO1]) as well as nonhomologous end joining DNA repair genes (XRCC4, XRCC5, and XRCC6) with induction of chromosomal aberrations. The participants consisted of 123 healthy males who were genotyped using polymerase chain reaction-based methods. Primary cultures of whole blood were treated with sodium arsenite (NaAsO(2); iAs(III); at final concentration 1 µmol/L), mitomycin C (at final concentration 60 ηg/mL; as positive control), or untreated. For each culture, mitotic index (MI), chromatid breaks (CBs), CAs, and total percentage of aberrant cells were determined. The levels of CB and percentage of aberrant cells were significantly higher in the TT genotype of CAT (C-262T polymorphism) than the CC genotype. The CB value in samples with GSTM1 active genotype was significantly higher than the null genotype. The MI in samples with TT genotype of NQO1 (C609T polymorphism) was significantly higher than MI in samples having CC and CT genotypes. There was no association between MI, CB, CA, and percentage of aberrant cells and polymorphisms of XRCC4, XRCC5, and XRCC6.

Genotoxicity and tumor inducing potential of roadside soil samples exposed to heavy traffic emissions at Amritsar (Punjab), India

Noxious gases released from vehicles adversely affect the microbial population of the roadside soil as well as exerts influence on plant growth and development. Considering the increasing vehicular pollution in Amritsar, a holy city of Punjab (India) and their serious consequences in terms of health problems, the present study was planned to estimate genotoxic and tumor inducing potentials of soil samples from Golden temple (GT) and Putlighar Chowk (PG) by employing Allium cepa root chromosomal aberration assay (AlRCAA) and Potato disc tumor assay (PDTA), respectively. The genotoxic potential in terms of percent aberrant cells in A. cepa was found to be 29.24 % (GT) and 29.24 % (PG) during in situ treatment and 39.00 % (GT) and 39.48 % (PG) during root dip treatment. The average number of tumors was found to be 14.4 in PG sample, followed by 13.0 in GT sample. Both samples have shown high content of lead viz., 39.81 (GT) and 56.48 (PG) during physicochemical analysis of the samples.

Analysis of biomarkers in a Czech population exposed to heavy air pollution. Part II: chromosomal aberrations and oxidative stress

Populations living in industrialised regions are at higher risk of a number of diseases and shortened life span. These negative effects are primarily brought about by damage to cells and macromolecules caused by environmental pollutants. In this study, we analysed the effect of exposure to benzo[a]pyrene, a particulate matter of aerodynamic diameter < 2.5 µm (PM2.5), and benzene on oxidative stress markers [including 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), 15-F(2t)-isoprostane (15-F2t-IsoP) and protein carbonyls] and cytogenetic parameters (stable and unstable chromosomal aberrations). The samples were collected from subjects living in the Ostrava region characterised by very high levels of air pollution and in Prague with comparatively lower concentrations of pollutants in three seasons (winter 2009, summer 2009 and winter 2010). Despite several-fold higher concentrations of air pollutants in the Ostrava region, the levels of stable aberrations (genomic frequency of translocations per 100 cells, percentage of aberrant cells and frequency of acentric fragments) were mostly comparable in both locations. The frequency of unstable aberrations measured as the number of micronuclei was unexpectedly significantly lower in the Ostrava region subjects in both seasons of 2009. Urinary excretion of 8-oxodG did not differ between locations in either season. Lipid peroxidation measured as levels of 15-F2t-IsoP in blood plasma was elevated in the Ostrava subjects sampled in 2009. Protein oxidation was higher in Prague samples collected in summer 2009. Multivariate analyses conducted separately in subjects from Prague and Ostrava showed a negative association between the frequency of micronuclei and concentrations of benzo[a]pyrene and PM2.5 in both regions. A positive relationship was observed between lipid peroxidation and air pollution; protein oxidation seems to be positively affected by PM2.5 in both regions.

Percentage of aberrant cells in uveal melanoma correlates with the patient’s prognosis

AbstractPurpose Uveal melanoma (UM) is the most common type of intra‐ocular malignancy in adults with an annual incidence of 5‐7 cases per million. Almost half of all patients with UM eventually die due to often late appearing metastases. Several clinical, pathological, and genetic factors have been identified as prognostic markers in UM. Non‐random chromosomal alterations for instance are present in over 80% of cases and complete loss of chromosome 3, (seen in 50% of all UM) relates to a 4‐year overall survival rate of only 30%.Methods Fluorescence in situ hybridisation (FISH) can be used to evaluate aneuploidy in the tumour cells. This FISH technique enables an in situ analysis of exact number/ percentage of tumour cells displaying that particular chromosomal aberration. Tumour heterogeneity has been observed in UM and an obvious question is whether lower percentages of abnormal cells are related to a change in patient’s outcome or prognosis.Results In this study, we assessed the percentages of aberrant tumour cells with FISH for each tumour (N=221) using chromosome 3 and 8 probes.Conclusion For both anomalies we could demonstrate that a high percentage aberrant tumour cells correlate well with a significantly worse prognosis for the patient. Commercial interest

Expression of XRCC5 in peripheral blood lymphocytes is upregulated in subjects from a heavily polluted region in the Czech Republic

Air pollution causes oxidative damage to macromolecules, chromosomal aberrations and changes in gene expression. We investigated the levels of oxidative stress markers [8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG), 15-F 2t-isoprostane (15-F2t-IsoP), protein carbonyls] and cytogenetic parameters [genomic frequency of translocations ( F G/100), percentage of aberrant cells (%AB.C.) and acentric fragments (ace)] in subjects living in Prague and in the heavily polluted Ostrava region. We also compared the expression of genes participating in base excision repair (BER) and non-homologous end-joining (NHEJ). We analyzed 64 subjects from Prague and 75 subjects from Ostrava. We measured oxidative stress markers by ELISA, cytogenetic parameters by fluorescence in situ hybridization and gene expression by quantitative PCR. The levels of air pollutants (benzo[a]pyrene, B[a]P; carcinogenic polycyclic aromatic hydrocarbons, c-PAHs; benzene) measured by personal monitors were significantly elevated in Ostrava compared to Prague ( p < 0.001). Despite this fact, we observed no differences in biomarkers of oxidative stress between the two locations. Moreover, subjects from Ostrava were less likely to have above-median levels of %AB.C. (OR; 95% CI: 0.18; 0.05–0.67; p = 0.010). Multivariate analyses revealed that subjects living in Ostrava had increased odds of having above-median levels of XRCC5 expression (OR; 95% CI: 3.33; 1.03–10.8; q = 0.046). Above-median levels of 8-oxodG were associated with decreased levels of vitamins C (OR; 95% CI: 0.37; 0.16–0.83; p = 0.016) and E (OR; 95% CI: 0.25; 0.08–0.75; p = 0.013), which were elevated in subjects from Ostrava. We suggest that air pollution by c-PAHs affects XRCC5 gene expression, which probably protects subjects from Ostrava against the induction of a higher frequency of translocations; elevated vitamin C and E levels in the Ostrava subjects decrease the levels of 8-oxodG.

Oxidative stress and chromosomal aberrations in an environmentally exposed population

We investigated the effect of the seasonal variability of environmental air pollutants on oxidative stress and cytogenetic biomarkers in a group of 59 city policemen working in Prague, Czech Republic. The studied group was monitored in February and May 2007. The exposure to environmental pollutants (carcinogenic polycyclic aromatic hydrocarbons, c-PAHs, including benzo[a]pyrene, B[a]P, and particulate matter of aerodynamic diameter < 2.5 μm, PM2.5) was measured by personal and/or stationary monitors. Levels of c-PAHs were significantly higher in winter than spring, while exposure to PM2.5 was higher in May than in February 2007. We did not observe any significant difference between the two seasons for any biomarker of oxidative stress (8-oxo-7,8-dihydro-2′-deoxyguanosine, 8-oxodG, 15-F 2t-isoprostane, 15-F 2t-IsoP, protein carbonyl levels) or any cytogenetic parameter, including the genomic frequency of translocations ( F G/100), the percentage of aberrant cells (%AB.C.) or the number of acentric fragments (ace). Analyses of associations between oxidative stress biomarkers and cytogenetic parameters showed a negative relationship between protein oxidation and F G/100, as well as protein oxidation and ace. We further analyzed the effect of air pollution on all subjects regardless of the season. Data from stationary monitors showed that 8-oxodG levels were significantly increased by exposure to PM2.5 over a 2-day period before sampling and by exposure to B[a]P over a 28-day period, days 57–84 before sampling. 15-F 2t-IsoP levels were increased after exposure to B[a]P over both 2-day and 3-day periods preceding sample collection and after exposure to c-PAHs over a 2-day period before sampling. %AB.C. was significantly affected by exposure to B[a]P over a 14-day period, days 57–70 before sampling. In summary, our results indicate that the exposure to environmental pollutants affects urinary excretion of 8-oxodG, lipid peroxidation and the frequency of chromosomal aberrations.

Chromosomal damage induced by vanadium oxides in human peripheral lymphocytes

Fly ash, the inorganic residue resulting from the combustion of some fuels, may almost exclusively contain vanadium oxides, compounds which exert potential toxic effects on a wide variety of in vitro and in vivo biological systems. Because information related to the oxidation state responsible for inducing genotoxic effects is controversial, the aim of the present study was to evaluate the effects of three vanadium salts in vitro. Human peripheral lymphocyte cultures were exposed to 1, 2, 4, or 8 μg/mL of vanadium(III) trioxide, vanadium(IV) tetraoxide, or vanadium(V) pentoxide (V2O3, V2O4, or V2O5, respectively). These cultures were then screened for structural chromosomal aberrations, and mitotic index (MI) measurements were made. Cytogenetic evaluations showed that only V2O4 increased the percentage of aberrant cells (without gaps) and chromosome damage (including and excluding gaps), while all compounds led to a decrease in the MI. These results demonstrate that vanadium(III), vanadium(IV), and vanadium(V) are all capable of inducing cytotoxicity, but only oxidation state IV induces clastogenic effects.

Genotoxicity of Different tert-Butylcalix[4]crowns

The ability of two calix[4]arene derivatives, namely 25,27-p-tert-butylcalix[4]dithiooxabenzocrown (1) and 25,27-p-tert-butylcalix[4]trithiooxabenzocrown (2), to produce chromosomal aberrations in root meristematic cells of Allium cepa and micronuclei (MN) in normochromatic erythrocytes (NCE) of Balb/c mice was investigated. NCE are normal mature red blood cells with a full complement of hemoglobin but lack ribosomes. In the first test, the root tips were treated with a series of concentrations of the two test chemicals ranging from 10(-7) to 10(-4) M for 24 or 48 h. Both compounds caused concentration-dependent increases in the percentage of aberrant cells and reductions in the mitotic index. These effects depended, to some extent, on the duration of the treatment. The most conspicuous chromosomal abnormalities were c-mitosis, chromosome bridges, chromosome breaks, chromosome lags as well as micronuclei and multinuclei. In the second test, acridine orange fluorescent staining was applied to evaluate the incidence of MN in NCE of mice intraperitoneally injected with varying contents of the two test chemicals (0.02-0.08 mg/mouse). The two chemicals induced dose-dependent MN formation as compared to the negative control. The second compound had more pronounced cytogenetic influence than the first one. Mitomycin C (MMC, 14 mg/kg body weight), employed as positive control, produced more obvious effects on the parameters investigated.

Toxicity assessment of natural waters from the Obninsk radioactive waste repository

The assessment of cyto- and genotoxicity of water samples from a regional radioactive waste repository using the Allium- test was carry out. Biotesting of natural waters from the site has demonstrated that negative biological effects are generated under the influence of water from well, located near the source of contamination. The percentage of aberrant cells in water samples from this well 4 is 2 times higher than in the control or other sources. Effects of water composition at the genome level are season independent. The Allium- test was shown to be highly sensitive and effective in testing a combined effect from radiation and chemical factors in field conditions.