Evaluation of the genetic damage to workers in a Greek shipyard

Shipyards are industrial areas where workers are likely exposed to environmental pollutants such as welding fumes, fine organic solvent and dye dust, that render the occupational environment a high risk one. Assessing the risk that workers are exposed to is a high critical factor in improving their working conditions. The present study aims to investigate the potential genetic damage to workers exposed to a harsh environment in a Greek shipyard. It is focused on assessing the percentage of induced micronuclei, as well as on changes in the various cell types of shipyard workers’ oral mucosa epithelium by implementing the buccal micronucleus cytome assay. Exposed workers appeared with statistically significant induced micronuclei as compared to office employees. Statistically, significant cell lesions were detected and are related to workers’ exposure to environmental conditions. The workers’ smoking habit contributed as well to the observed buccal epithelial cell alterations. The observed data signify the high-risk workers are exposed; resulting in the shipyard’s management the need to implement measures improving the working environment conditions and to reevaluate the workers’ personal protective equipment requirements.     

Intramuscular Administration of Very High Dose of a-Tocopherol Protects Liver from Severe Ischemia/Reperfusion Injury

The effect of intramuscular administration of high (30 mg/kg body weight for 3 days) or very high (300 mg/kg body weight for 3 days) doses of a-tocopherol to Wistar rats subjected to total severe warm hepatic ischemia and reperfusion was investigated. After a 60-minute period of total hepatic ischemia and 120 minutes of reperfusion, animals were killed, and liver samples were taken for determination of malondialdehyde (MDA) and histological examinations. Blood samples were also taken for assay of serum a-tocopherol, alanine transaminase (ALT), aspartate transaminase (AST), and lactic dehydrogenase (LDH). Additional animals were followed for a 7-day survival rate determination. Results showed that ischemia and reperfusion decreased the survival rate to 10%, whereas the levels of AST, ALT, and LDH in serum were increased compared with levels in animals that were sham operated. The MDA concentrations in liver were also increased, from 1.142 to 1.567 nmoles/g, whereas the levels of a-tocopherol in serum were decreased from 10.20 to 1.80 mmol/L. Pretreatment with a-tocopherol increased the viability to 50% and 70%, for the high and very high doses, respectively, and decreased the levels of AST, ALT, and LDH in serum. It also decreased the MDA concentrations in liver to 0.975 and 0.774 nmoles/g for the high and very high doses of a-tocopherol, respectively, whereas it increased the level of a-tocopherol in serum to 11.25 and 13.02 mmol/L for the high and very high doses, respectively. Histological examinations showed protection of the liver parenchyma in the animals treated with a-tocopherol.     

Parents' causal attributions about attention deficit/hyperactivity disorder: the effect of child and parent sex

BACKGROUND: Boys with attention deficit/hyperactivity disorder (AD/HD) demonstrate disruptive behaviour at significantly higher rates compared to girls. Disruptive behaviour often develops as a result of negative interaction patterns within the caregiving relationship. Given the importance of parental cognitions as mediators of parental behaviour, the consideration of parent and child sex in the investigation of causal attributions regarding AD/HD may, at least partially, explain sex differences in the prevalence of disruptive behaviour among children with AD/HD. AIM: To examine the effect of parent and child sex on parental causal attributions and reactions about AD/HD and to investigate the interrelationships between these variables. SAMPLE: Three hundred and seventeen mothers and 317 fathers of boys and girls aged 4-6 years and enrolled in kindergartens in Athens. METHOD: A Greek version of the Parental Account of the Causes of Childhood Problems Questionnaire was used, which followed a vignette about a hypothetical child displaying symptoms of AD/HD. Half of the participants received a male and another half received a female version of the vignette. RESULTS: The child's sex greatly influenced parents' causal attributions about AD/HD. Higher ratings of intentionality were conferred to boys with AD/HD than girls and these attributions were related to stricter responses towards boys. In contrast, parents who considered biological dysfunction as underlying AD/HD, they mostly did so in the case of girls. Minimal effect of parent sex on causal attributions was found. CONCLUSIONS: Because causal attributions of intentionality relate to the response of more strictness and such attributions are more prevalent for boys than girls, then these perceptions about the aetiology of AD/HD in boys may be at the basis of negative interaction patterns. The increase of such interaction patterns may place boys at a more vulnerable position towards the development of secondary behaviour problems.     

Electroencephalographic peak alpha frequency correlates of cognitive traits

EEG peak alpha frequency (PAF) has been shown to differentiate groups of adults with higher memory performance from those of lower performance, groups of children with advanced reading ability from matched controls, and to predict state-dependent working memory. The present study attempted to explore PAF as a predicting variable for verbal and attentional cognitive trait abilities in young adults. Nineteen undergraduate students had their EEG recorded during initial rest, reading, and post-reading rest, and at a different day were evaluated on reading, vocabulary, and attentional performance. Results showed significant correlations of reading vocabulary and response control with PAF during reading and post-reading recordings, but not during initial rest. PAF may reflect some general cognitive ability that is not necessarily memory or reading, possibly response control or the ability to acquire vocabulary. It is suggested that cognitive ability traits may reflect the ability to induce cognitive states.     

Immunohistochemical expression of metalloproteinases MMP-2 and MMP-9 in abdominal aortic aneurysms: correlation with symptoms and aortic diameter

Our purpose was to investigate the expression of matrix metalloproteinase (MMP)-2 and -9 in all types of abdominal aortic aneurysms (AAA): symptomatic, asymptomatic, and ruptured. MMP-2 and -9 activity was investigated in surgical samples from the arterior wall of 46 AAA, using a standard immunohistochemical technique. The MMP-9 activity was significantly higher in large AAA (>6 cm), but there was no relation between AAA size and MMP-2 activity. Neither MMP-2 nor MMP-9 were related with AAA rupture, other complications or symptoms. The MMP-9 activity in AAA is a determinant of the aneurysm size, but it is not related to clinical manifestations.     

Neurocognitive and behavioral functioning in frontal lobe epilepsy: a review

Frontal lobe epilepsy (FLE) is a seizure disorder with a lower prevalence than temporal lobe epilepsy (TLE). Despite its consequences on cognitive and emotional well-being, the neuropsychology of FLE has not been well studied. By contrast, TLE has been studied meticulously, leading to a relevant understanding of memory and the functional characteristics of the temporal and limbic circuits. The neuropsychological studies on FLE report deficits in motor coordination and planning, reduced attention span, and difficulties in response inhibition in complex cognitive tasks. This review aims to illustrate the most relevant neurocognitive dimensions, psychiatric comorbidity, and postoperative neuropsychological outcome of FLE. Methodological suggestions for future research are also included by critically reviewing the existing literature.     

Markov switching stochastic frontier model

Summary In this paper, we propose a new approach to stochastic frontier models, viz., a Markov switching structure to accommodate cross‐sectional parameter heterogeneity and temporal variation in the parameters and technical inefficiency distributions. The Markov Chain Monte Carlo techniques are developed and implemented for Bayesian inferences on parameters and technical efficiency. We illustrate new methods by estimating world production frontiers using international panel data on 59 countries observed for 26 years.