Coelomocyte biomarkers in the earthworm Eisenia fetida exposed to 2,4,6-trinitrotoluene (TNT)

Contamination by 2,4,6-trinitrotoluene (TNT) is a global environmental problem at sites of former explosive production, handling, or storage, and could have deleterious consequences for human and ecological health. We investigated its sublethal effects to Eisenia fetida, using two nonspecific biomarkers. In coelomocytes of earthworms exposed 24, 48, or 72 h, we evaluated DNA damage (comet assay) and neutral red retention time (NRRT), using the filter paper contact test. Both percentage of damage (D%) and calculated damage index showed significant DNA damage at almost all concentrations, at all time points assayed. Along exposure time, two different patterns were observed. At the lower TNT concentrations (0.25?C0.5 ??g/cm²) an increased DNA migration at 48 h, with a decrease close to initial levels after 72 h exposure, was observed. This decrease could be attributed to activation of the DNA repair system. At higher concentrations (1.0?C2.0 ??g/cm²), the high DNA damage observed remained constant during the 72 h exposure, suggesting that the rate of DNA repair was not enough to compensate such damage. Analysis of NRRT results showed a significant interaction between time and treatment. After 48 h, a significant decrease was observed at 4.0 ??g/cm². After 72 h, NRRT presented a concentration-dependent decrease, significantly different with respect to control at 0.5, 1.0, 2.0, and 4.0 ??g/cm². The two assayed methods, performed on the same sample, showed clear responses to sublethal TNT exposure in E. fetida, providing sensitive unspecific biomarkers of cell injury and DNA damage.     

The link between pharmaceuticals and cyanobacteria: a review regarding ecotoxicological,ecological, and sanitary aspects

Environmental Science and Pollution Research - Cyanobacteria are important for ecosystem functioning, but eutrophication may affect the surrounding biome by losing ecosystem services and/or through...     

Prenatal molecular diagnosis in hypertrophic cardiomyopathy: report of the first case

Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease that may cause premature sudden death, especially in teenagers and young adults. The recent progress in the molecular genetics of the disease has made genetic testing sometimes available in clinical practice. We report the case of a couple who still requested prenatal molecular testing after detailed information had been given through a multidisciplinary consultation. Prenatal diagnosis in HCM is associated with complex medical and psychological implications, in addition to general ethical considerations, as the potential value of the diagnosis is counterbalanced by the highly variable expression of the disease and the difficulty in predicting its evolution. The R403L mutation in the MYH7 gene had been previously identified in this family, characterized by a malignant form of HCM. In the specific context of this case, we decided to agree to the request of the parents and performed the prenatal diagnosis. To the best of our knowledge, this is the first report of a prenatal molecular diagnosis performed in the context of HCM. Copyright © 2004 John Wiley & Sons, Ltd.     

Screening for fetal Down syndrome with maternal serum hCG and oestriol: A prospective study

We report the preliminary results of a prospective study aimed at evaluating the effectiveness of Down syndrome (DS) screening using second-trimester measurement of maternal serum human chorionic gonadotrophin (hCG) and unconjugated oestriol (uE3) together with maternal age. Reference values for hCG, uE3, and the hCG/uE3 ratio in normal pregnancies were established from more than 3000 normal gestations and found to follow a log-normal statistical distribution. Risk evaluation was made using reference values for affected pregnancies from retrospective studies. Screening of 10 000 women under 38 years resulted in 412 amniocenteses and the prenatal diagosis of six cases of DS, whereas four cases remained undetected until term. In a parallel study, diagnostic amniocentesis was performed in women over 38 years and in women with a previous affected child, and an evaluation of the risk of fetal DS based on serum hCG and uE3 levels was made in all cases. Fourteen cases of DS were detected. Median values for hCG and uE3 in the 24 affected pregnancies were close to the 90th and tenth centiles of the normal reference values, respectively, and thus are in good agreement with the values reported by others in retrospective studies.     

The Amoco Cadiz oil spill. Distribution and evolution of hydrocarbon concentrations in seawater and marine sediments

The shipwreck of the Amoco Cadiz supertanker on the rocks of the Brittany Coast of France (March, 1978) was one of the most disastrous oil spills ever recorded. The crude oils discharged in the marine environment were light petroleums. The distribution and the evolution of the oil pollution in the marine environment was examined. Chemical studies were limited to an overall estimate of the oil content to assess the importance and the extent of the pollution at the surface, in the water column, and in the sediment. UV fluorescence spectroscopy was used to detect oil in the seawater samples and IR spectrophotometry was used to analyze the sediment samples. Hydrocarbon concentrations in seawater ranged from 0.5 μ/1 to more than 100 μg/1. The oil spill has affected a very large section of the western English Channel. The diffusion of the hydrocarbons into the water column was observed. The evolution of the seawater pollution was followed, and the half-life of hydrocarbons in subsurface water was found to be between 11 and 28 days in different areas. One month after the disaster, the marine sediments were contaminated in the areas reached by the drifting slicks. The highest accumulation of petroleum in the sediments was located in the sheltered coastal environments. The natural decontamination process was found to be related to the nature of the sediment and the energy level of the geographic zone.     

Formulation,calibration, and validation of hybrid and coupled models for the design of upflow anaerobic filters in multiple separated stages for organic matter removal from sanitary landfill leachates

In this paper, the formulation, calibration, and validation of hybrid and coupled models for the design of upflow anaerobic filters in multiple separated stages were developed for organic matter removal from sanitary landfill leachates. Three novelties were presented, the type of reactor, design models, and kinetic coefficients. The upflow anaerobic filters were separated into two and three stages identified as UAF-2SS (DI-FAFS, in Spanish) and UAF-3SS (TRI-FAFS, in Spanish). The formulation, calibration, and validation of mathematical structures of hybrid models and five coupled models are proposed for each reactor. The hybrid models are based on the law of mass conservation, with the organic matter transformation component within the UAF-2SS and UAF-3SS reactors, being estimated from empirical equations that have been tested in aerobic culture reactors, adapted to the experimental factors, including among these, those under a non-stationary—advective conditions based on Velz's Law, Phelps's Law, and Monod's equation. The coupled models combine the components of the molecular transport by biosorption and molecular diffusion processes, with adaptations of the Stack's equation and Fick's Law, as well as transformation of organic substrates by biomass, whose kinetic coefficients contribute to explain the fraction, in which, the processes of mobility and biochemical transformation of the organic matter are occurring in the biomass within the bioreactors.     

Trace-metal contamination in the glacierized Rio Santa watershed,Peru

The objective of this research is to characterize the variability of trace metals in the Rio Santa watershed based on synoptic sampling applied at a large scale. To that end, we propose a combination of methods based on the collection of water, suspended sediments, and riverbed sediments at different points of the watershed within a very limited period. Forty points within the Rio Santa watershed were sampled between June 21 and July 8, 2013. Forty water samples, 36 suspended sediments, and 34 riverbed sediments were analyzed for seven trace metals. The results, which were normalized using the USEPA guideline for water and sediments, show that the Rio Santa water exhibits Mn concentrations higher than the guideline at more than 50% of the sampling points. As is the second highest contaminating element in the water, with approximately 10% of the samples containing concentrations above the guideline. Sediments collected in the Rio Santa riverbed were heavily contaminated by at least four of the tested elements at nearly 85% of the sample points, with As presenting the highest normalized concentration, at more than ten times the guideline. As, Cd, Fe, Pb, and Zn present similar concentration trends in the sediment all along the Rio Santa.The findings indicate that care should be taken in using the Rio Santa water and sediments for purposes that could affect the health of humans or the ecosystem. The situation is worse in some tributaries in the southern part of the watershed that host both active and abandoned mines and ore-processing plants.