Blood cell morphology of Djungarian hamster (Phodopus sungorus)

Djungarian hamsters (Phodopus sungorus) are increasingly used as a laboratory model, but published information on their blood cell morphology has not been available. The aim of this study was to describe the morphologic characteristics of peripheral blood cells of P. sungorus.Erythrocytes had an average diameter of 6.02 ?m, ranging between 4 and 7.5 ?m; thus they were smaller than those of other Cricetine (hamster) species. Polychromatic (immature) erythrocytes were relatively abundant, as is common in rodent species. The differential count of leukocytes was similar to that of the golden hamster. The percentage of neutrophils and monocytes was slightly higher than in the golden hamster, while that of lymphocytes was somewhat lower. Neutrophils ranged in size from10-12 ?m, containing neutrophilic granules and well-defined nuclear lobes. Lymphocytes diameters were 9-12 ?m. Small lymphocytes were the most abundant. Monocytes ranged in size from 10-16 ?m, being the largest cells. Eosinophils varied in size from 10-14 ?m, and displayed a ringed nucleus

Pruebas citogenéticas aplicadas al control de alimentos de origen animal

La presencia de compuestos tóxicos en alimentos de origen animal representa un importante factor de riesgo para la salud humana. Además de la detección de las concentraciones de esas sustancias en los productos animales, los ensayos citogenéticos pueden representar un método útil para evaluar los efectos de tales compuestos. Las aberraciones cromosómicas, los intercambios de crómatidas hermanas, el test de la cometa y la prueba de micronúcleos, son técnicas simples que permiten determinar el daño producido por una o más sustancias cuya presencia aún no pudo ser detectada mediante los métodos tradicionales

Clastogenicity and aneuploidy in newborn and adult mice exposed to 50 Hz magnetic fields.

Purpose:?To detect possible clastogenic and aneugenic properties of a 50 Hz, 650 ?T magnetic field. Materials and methods:?The micronucleus test with CREST (Calcinosis, Raynaud's phenomenon, Esophageal dismotility, Sclerodactility, Telangectasia) antibody staining was performed on liver and peripheral blood sampled from newborn mice exposed to an ELF (Extremely Low Frequency) magnetic field during the whole intra-uterine life (21 days), and on bone marrow and peripheral blood sampled from adult mice exposed to the same magnetic field for the same period. Results:?Data obtained in newborn mice show a significant increase in micronuclei frequencies. In absolute terms, most of the induced micronuclei were CREST-negative (i.e., formed by a chromosome fragment). However, in relative terms, ELF exposure caused a two-fold increase in CREST-negative micronuclei and a four-fold increase in CREST-positive micronuclei (i.e., formed by a whole chromosome). No significant effect was recorded on exposed adults. Conclusions:?These findings suggest the need for investigation of aneugenic properties of ELF magnetic fields in order to establish a possible relationship to carcinogenesis

TERT Extra-Telomeric Roles: Antioxidant Activity and Mitochondrial Protection

Telomerase reverse transcriptase (TERT) is the catalytic subunit of telomerase holoenzyme, which adds telomeric DNA repeats on chromosome ends to counteract telomere shortening. In addition, there is evidence of TERT non-canonical functions, among which is an antioxidant role. In order to better investigate this role, we tested the response to X-rays and H2O2 treatment in hTERT-overexpressing human fibroblasts (HF-TERT). We observed in HF-TERT a reduced induction of reactive oxygen species and an increased expression of the proteins involved in the antioxidant defense. Therefore, we also tested a possible role of TERT inside mitochondria. We confirmed TERT mitochondrial localization, which increases after oxidative stress (OS) induced by H2O2 treatment. We next evaluated some mitochondrial markers. The basal mitochondria quantity appeared reduced in HF-TERT compared to normal fibroblasts and an additional reduction was observed after OS; nevertheless, the mitochondrial membrane potential and morphology were better conserved in HF-TERT. Our results suggest a protective function of TERT against OS, also preserving mitochondrial functionality

DNA damage in lens epithelial cells exposed to occupationally-relevant X-ray doses and role in cataract formation

The current framework of radiological protection of occupational exposed medical workers reduced the eye-lens equivalent dose limit from 150 to 20 mSv per year requiring an accurate dosimetric evaluation and an increase understanding of radiation induced effects on Lens cells considering the typical scenario of occupational exposed medical operators. Indeed, it is widely accepted that genomic damage of Lens epithelial cells (LEC) is a key mechanism of cataractogenesis. However, the relationship between apoptosis and cataractogenesis is still controversial. In this study biological and physical data are combined to improve the understanding of radiation induced effects on LEC. To characterize the occupational exposure of medical workers during angiographic procedures an INNOVA 4100 (General Electric Healthcare) equipment was used (scenario A). Additional experiments were conducted using a research tube (scenario B). For both scenarios, the frequencies of binucleated cells, micronuclei, p21-positive cells were assessed with different doses and dose rates. A Monte-Carlo study was conducted using a model for the photon generation with the X-ray tubes and with the Petri dishes considering the two different scenarios (A and B) to reproduce the experimental conditions and validate the irradiation setups to the cells. The simulation results have been tallied using the Monte Carlo code MCNP6. The spectral characteristics of the different X-ray beams have been estimated. All irradiated samples showed frequencies of micronuclei and p21-positive cells higher than the unirradiated controls. Differences in frequencies increased with the delivered dose measured with Gafchromic films XR-RV3. The spectrum incident on eye lens and Petri, as estimated with MCNP6, was in good agreement in the scenario A (confirming the experimental setup), while the mean energy spectrum was higher in the scenario B. Nevertheless, the response of LEC seemed mainly related to the measured absorbed dose. No effects on viability were detected. Our results support the hypothesis that apoptosis is not responsible for cataract induced by low doses of X-ray (i.e. 25 mGy) while the induction of transient p21 may interfere with the disassembly of the nuclear envelop in differentiating LEC, leading to cataract formation. Further studies are needed to better clarify the relationship we suggested between DNA damage, transient p21 induction and the inability of LEC enucleation

Studies of micronuclei and other nuclear abnormalities in red blood cells of Colossoma macropomum exposed to methylmercury

The frequencies of micronuclei (MN) and morphological nuclear abnormalities (NA) in erythrocytes in the peripheral blood of tambaqui (Colossoma macropomum), treated with 2 mg.L−1 methylmercury (MeHg), were analyzed. Two groups (nine specimens in each) were exposed to MeHg for different periods (group A - 24 h; group B - 120 h). A third group served as negative control (group C, untreated; n = 9). Although, when compared to the control group there were no significant differences in MN frequency in the treated groups, for NA, the differences between the frequencies of group B (treated for 120 h) and the control group were extremely significant (p < 0.02), thus demonstrating the potentially adverse effects of MeHg on C. macropomum erythrocytes after prolonged exposure

Assessment of the genotoxic impact of pesticides on farming communities in the countryside of Santa Catarina State, Brazil

The aim of this study was to assess the use of pesticides on farms located in the Lambedor River watershed in Guatambu, State of Santa Catarina, as well as to determine, by micronucleus testing, the risk of genotoxic impact. Samples from locally collected Cyprinus carpio, Hypostomus punctatus, Rhamdia quelen and Oreochromis niloticus gave evidence of a mean increase in micronuclei frequency from 6.21 to 13.78 in 1,000 erythrocytes, a clear indication of the genotoxic potenciality of pesticide residues in regional dams, and their significant contribution to local environmental contamination

Kavezno izlaganje lubina (Dicentrarchus labrax) u procjeni genotoksičnog utjecaja onečišćenja

Genotoxic effects are often the earliest signs of pollution-related environmental disturbance. In this study, we used the comet assay and micronucleus test to assess DNA damage in the erythrocytes of the European sea bass (Dicentrarchus labrax) exposed to environmental pollution in situ. Fish were collected from a fi sh farm in the Trogir Bay and their cages placed at an unpolluted reference site Šolta (Nečujam Bay) and a polluted site Vranjic (Kaštela Bay) for four weeks. A group of fi sh which remained at the fi sh farm Trogir Bay were used as the second control group. Fish exposed at the Vranjic site showed a signifi cantly higher erythrocyte DNA damage, measured by the comet assay, than either control group. Micronucleus induction showed a similar gradient of DNA damage, but did not reach statistical signifi cance. Our results show that cage exposure of a marine fi sh D. labrax can be useful in environmental biomonitoring and confi rm the comet assay as a suitable tool for detecting pollution-related genotoxicity.Genotoksični učinak često je jedan od najranijih pokazatelja štetnog djelovanja onečišćenja okoliša. U ovom radu procijenjeno je oštećenje DNA u eritrocitima lubina (Dicentrarchus labrax) izloženima okolišnom onečišćenju s pomoću komet-testa i mikronukleus-testa. Lubini su prikupljeni na ribogojilištu i kavezno izloženi u periodu od četiri tjedna na dvije postaje različitog stupnja onečišćenja na jadranskoj obali: na kontrolnoj postaji Šolta (zaljev Nečujam) i na onečišćenoj postaji Vranjic (Kaštelanski zaljev). Zasebna skupina lubina skupljena na ribogojilištu poslužila je kao druga kontrola. Rezultati komet-testa pokazali su statistički značajan porast oštećenja DNA na postaji Vranjic u usporedbi s obje kontrolne postaje. Rezultati mikronukleus-testa pokazali su sličan gradijent onečišćenja, iako nisu dosegli statističku značajnost. Ovi rezultati upućuju na primjenjivost kaveznog izlaganja lubina D. labrax u biomonitoringu vodenog okoliša te potvrđuju korisnost komet-testa kao prikladne metode za detekciju genotoksičnog utjecaja onečišćenja