Effects of pesticides on occupationally exposed humans

Pesticides are known to contain numerous genotoxic compounds; however, genotoxicity biomonitoring studies of workers occupationally exposed to pesticides have produced variable results. In this study, we employed the Comet assay to examine DNA damage in peripheral blood lymphocytes (PBLs) from 64 greenhouse workers from Almera in south-eastern Spain in comparison to PBLs from 50 men from the same area but not engaged in any agricultural work. The results indicated that there were no differences in the basal levels of DNA damage in the two study groups. In addition, exposure of PBL from the workers and controls to hydrogen peroxide or gamma-irradiation led to similar levels of DNA damage; the subsequent repair of the induced DNA damage was also similar for both study populations. Smoking had no impact on any of the responses. The results of this study indicate that the greenhouse workers had no detectable increase in DNA damage or alteration in the cellular response to DNA damage compared to our control population

DNA damage and repair efficiency in lymphocytes from schizophrenic patients

In the present study we examined schizophrenic patients' lymphocytes sensitivity to the effects of external factors, such as hydrogen peroxide and gamma-irradiation and also their repair efficiency with the comet assay. Our results did no show any difference in basal levels of DNA damage between schizophrenic and normal populations. The slightly increased sensitivity of the schizophrenic population to the externally induced DNA damage compared to controls was not statistically significant. Also the small reduction in the DNA repair efficiency in schizophrenics in comparison to normal population was found to be not statistically significant. Finally, patients with heritable predisposition to schizophrenia did not show any difference in their response from the other schizophrenics. (C) 2003 Elsevier Ireland Ltd. All rights reserved

Congenital rickets due to maternal vitamin D deficiency in a sunny island of Greece

A full-term male infant presented with clinical and biochemical findings consistent with the diagnosis of congenital rickets: weak muscle tone, craniotabes, episodes of tremor, hypocalcaemia, elevated serum alkaline phosphatase, secondary hyperparathyroidism, decreased 25-hydroxy-vitamin D and normal 1,25-dihydroxyvitamin D serum levels. The mother's history and biochemical findings suggested nutritional vitamin D deficiency. Treatment with calcium and vitamin D resulted in the disappearance of clinical findings of rickets, normalization of the baby's biochemical profile and normal growth. It is surprising that this case occurred in an affluent setting, in the Mediterranean island of Crete, with an abundance of sunlight throughout the year. Conclusion: We report this case in order to emphasize the continuing occurrence of congenital rickets even in populations not considered at risk for hypovitaminosis D. A high index of suspicion is required for prompt diagnosis and treatment, thus preventing complications

DNA damage and repair capacity in lymphocytes from obstructive sleep apnea patients

Obstructive sleep apnea (OSA) syndrome is a respiratory disease that is linked to heart attacks and high blood pressure. In the present study, we used the Comet assay to compare basal DNA damage and DNA damage induction by hydrogen peroxide, ethanol, and gamma-irradiation in lymphocytes from 35 OSA patients and 35 controls. We also measured the apoptosis and necrosis produced by these agents and the ability of the lymphocytes to repair the induced DNA damage. It was found that lymphocytes isolated from OSA patients had higher basal levels of DNA damage and were more, sensitive to the effects of the DNA-damaging agents than lymphocytes from controls. OSA patients also had a reduced capacity to repair the DNA damage induced by the three agents, but apoptosis and necrosis were similar in OSA patients and the controls

DNA damage in a human population affected by chronic psychogenic stress

The effects of chronic psychogenic stress on the expression of DNA damage and cellular response to the damage were investigated. Using the comet assay, basal DNA damage was found to be similar in lymphocytes of both affected and non-affected Populations (n = 30 in both groups). The induction of DNA damage in lymphocytes by external factors (H2O2 and gamma-irradiation), was also investigated. In these Studies, cells were treated with 50, 100 and 150 muM H2O2 for 5 minutes or with 0.8, 2.5 and 4.2 Gy gamma-rays. A significant difference was found between the chronically stressed and the control populations, indicating the enhanced sensitivity of the former population. Cells were also held for 2 hours after the treatment, allowing time for the cells to deal with the induced DNA damage. Based on the level of residual DNA strand breaks, cells from the stressed population had more breaks than the controls. Gender does not alter these findings. In conclusion, our data indicate that cells from the stressed population were more sensitive to the induction of DNA damage and had higher level of residual damage. Therefore, stress conditions may cause the affected individuals to be susceptible to environmental mutagenic agents

DNA damage and repair capacity in lymphocytes from obstructive sleep apnea patients

Obstructive sleep apnea (OSA) syndrome is a respiratory disease that is linked to heart attacks and high blood pressure. In the present study, we used the Comet assay to compare basal DNA damage and DNA damage induction by hydrogen peroxide, ethanol, and γ-irradiation in lymphocytes from 35 OSA patients and 35 controls. We also measured the apoptosis and necrosis produced by these agents and the ability of the lymphocytes to repair the induced DNA damage. It was found that lymphocytes isolated from OSA patients had higher basal levels of DNA damage and were more sensitive to the effects of the DNA-damaging agents than lymphocytes from controls. OSA patients also had a reduced capacity to repair the DNA damage induced by the three agents, but apoptosis and necrosis were similar in OSA patients and the controls. © 2007 Wiley-Liss, Inc

RANTES promoter gene polymorphisms and susceptibility to severe respiratory syncytial virus-induced bronchiolitis

Background: Severe respiratory syncytial virus (RSV) infection is characterized by enhanced chemokine activity. Several studies have linked increased regulated on activation, normal T cell expressed and secreted (RANTES) expression with severe RSV disease. Three single nucleotide polymorphisms, -28C/G, -403G/A, and In1.1T/C in the RANTES gene, have been correlated with the gene's transcriptional activity. In the present study, we explored the possible correlation of the genetic variability of the RANTES gene with the clinical manifestation of RSV disease. Methods: DNA samples were obtained from 106 children hospitalized for RSV bronchiolitis, in a 2-year period. One hundred twenty sex-matched healthy adults, without a history of severe lower respiratory tract infections, formed the control group. Results: No association was established between -28C/G polymorphism and RSV-induced bronchiolitis, mainly because of its extreme rarity in the studied population. No statistically significant differences were observed in cases and controls regarding genotype and allele frequencies of each of the In.1.1T/C and -403G/A polymorphisms. By contrast, the -28C/C-403G/AIn1.1T/T combined genotype was significantly more common in cases than in controls. Conclusions: Our results indicate an association between a common genotype with severe RSV infection. This observation supports the previously reported results indicating RANTES as an important mediator of RSV infection

DNA damage and repair efficiency in lymphocytes from schizophrenic patients

In the present study we examined schizophrenic patients’ lymphocytes sensitivity to the effects of external factors, such as hydrogen peroxide and gamma-irradiation and also their repair efficiency with the comet assay. Our results did no show any difference in basal levels of DNA damage between schizophrenic and normal populations. The slightly increased sensitivity of the schizophrenic population to the externally induced DNA damage compared to controls was not statistically significant. Also the small reduction in the DNA repair efficiency in schizophrenics in comparison to normal population was found to be not statistically significant. Finally, patients with heritable predisposition to schizophrenia did not show any difference in their response from the other schizophrenics. (C) 2003 Elsevier Ireland Ltd. All rights reserved

Effects of pulsed electric fields on DNA of human lymphocytes

The effects of pulsed electric fields of low frequency (50 Hz) on DNA of human lymphocytes were investigated. The influence of additional external factors, such as hydrogen peroxide (H2O2) and gamma-irradiation, as well as the repair efficiency in these lymphocytes, was also evaluated. The comet assay, a very sensitive and rapid method for detecting DNA damage at the single cells level was the method used. A significant amount of damage was observed after exposure to the electric fields, compared to the controls. After 2 h incubation at 37 degrees C, a proportion of damage was repaired. H2O2 and gamma-irradiation increased the damage to lymphocytes exposed to pulsed electric fields according to the dose used, while the amount of the repair was proportional to the damage

Dietary habits of Greek primary school children

The purpose of this study was to assess Greek primary (1st to 6th grade) school children's dietary habits and the factors influencing them. Our results show that children know the value of different foods. The socio-economic status of father has no effect on the attitude of children towards choosing their diet, however, mothers' educational status appears to have an effect on their children's behaviour. Place of residence (urban or semi-rural areas) and gender does not influence their knowledge about different diets. It was, finally, shown that as children grow older they tend to eat less healthy foods. © 2006 Springer Science+Business Media, LLC