An integrated environmental approach to investigate biomarker fluctuations in the blue mussel Mytilus edulis L. in the Vilaine estuary, France

Estuarine areas represent complex and highly changing environments at the interface between freshwater and marine aquatic ecosystems. Therefore, the aquatic organisms living in estuaries have to face highly variable environmental conditions. The aim of this work was to study the influence of environmental changes from either natural or anthropogenic origins on the physiological responses of Mytilus edulis. Mussels were collected in the Vilaine estuary during early summer because this season represents a critical period of active reproduction in mussels and of increased anthropogenic inputs from agricultural and boating activities into the estuary. The physiological status of the mussel M. edulis was evaluated through measurements of a suite of biomarkers related to: oxidative stress (catalase, malondialdehyde), detoxication (benzopyrene hydroxylase, carboxylesterase), neurotoxicity (acetylcholinesterase), reproductive cycle (vitelline, condition index, maturation stages), immunotoxicity (hemocyte concentration, granulocyte percentage, phagocytosis, reactive oxygen species production, oxidative burst), and general physiological stress (lysosomal stability). A selection of relevant organic contaminant (pesticides, (polycyclic aromatic hydrocarbons, polychlorobiphenyls) was measured as well as environmental parameters (water temperature, salinity, total suspended solids, turbidity, chlorophyll a, pheopigments) and mussel phycotoxin contamination. Two locations differently exposed to the plume of the Vilaine River were compared. Both temporal and inter-site variations of these biomarkers were studied. Our results show that reproduction cycle and environmental parameters such as temperature, organic ontaminants, and algal blooms could strongly influence the biomarker responses. These observations highlight the necessity to conduct integrated environmental approaches in order to better understand the causes of biomarker variations.     

Temporal variations in the level of chlordecone in seawater and marine organisms in Martinique Island (Lesser Antilles)

Environmental Science and Pollution Research - The present study, conducted in the Galion Bay in Martinique, aims to highlight the temporal and seasonal variations of chlordecone contamination (an...     

Biotransformation of the flame retardant tetrabromo-bisphenol A by human and rat sub-cellular liver fractions

The comparative in vitro metabolism of the flame retardant tetrabromo-bisphenol A was studied in rat and human using a [(14)C]-radio-labelled molecule. Tetrabromo-bisphenol A is metabolised into the corresponding glucuronide (liver S9 fractions) and several other metabolites produced by cytochrome P450 dependent pathways (liver microsomes and liver S9 fractions). No major qualitative differences were observed between rat and human, regardless of the selected concentration, within the 20-200 microM range. Tetrabromo-bisphenol A undergoes an oxidative cleavage near the central carbon of the molecule, that leads to the production of hydroxylated dibromo-phenol, hydroxylated dibromo-isopropyl-phenol and glutathione conjugated dibromo-isopropyl-phenol. The main metabolites of tetrabromo-bisphenol A are two molecules of lower polarity than the parent compound, characterised as a hexa-brominated compound with three aromatic rings and a hepta-brominated dimer-like compound, respectively. Both structures, as well as the lower molecular weight metabolites resulting from the breakdown of the molecule, suggest the occurrence of chemically reactive intermediates formed following a first step oxidation of tetrabromo-bisphenol A.     

Pathophysiology,diagnosis and management of prenatal upper tract dilatation

Upper tract dilatation presenting as renal pelvis dilatation with or without ureteric dilatation is one of the more common abnormalities detected on prenatal ultrasound scanning. The majority of cases are due to pelvi-ureteric and vesico-ureteric junction anomalies, and vesico-ureteric reflux. Prenatal diagnosis with ultrasound may be aided by biochemical analysis of fetal blood and urine. The natural history of prenatally detected abnormalities remains under review. Precise diagnosis, and therefore prognosis, may not be made until after birth. Copyright © 2001 John Wiley & Sons, Ltd.     

Prenatal diagnosis of exophytic nevus sebaceous of the scalp

Nevus sebaceous is a complex hamartoma most commonly found on the scalp, face, and neck and is often present at birth, although some may be diagnosed later in infancy. We report the first prenatal diagnosis of isolated nevus sebaceous that presented at 19 weeks' gestation as a large and exophytic tumor of the scalp. This case emphasizes the crucial role of ultrasound examination performed with high-frequency probes, which revealed associated diffuse lesions of the face. Identification of such a facial involvement could have a dramatic prognostic impact. © 2013 John Wiley & Sons, Ltd.     

人工湿地植物对高盐废水中COD的去除作用

针对经生化处理的石油和精细化工工业区的工业废水盐含量较高、氮磷营养盐含量较低和COD含量较高的特点,构建了高盐度进水条件下表面流人工湿地的中试试验装置,考察了水葱、芦苇和香蒲在此类高盐废水中的生长状况,比较了三种植物混合试验单元与无植物试验单元对此类高盐废水中COD的去除效果,研究了高含盐量工业废水湿地系统内植物生长对微生物量的影响,以及植物在微生物去除COD过程中的作用。结果表明,高含盐量的工业废水对水葱、芦苇和香蒲的生长有一定的抑制作用,植物单元对工业废水中有机物的净化效果明显好于无植物单元,且植物生长越好,人工湿地内水体中的COD净化效果越好。混合植物单元对高含盐量工业废水中COD的总去除量约为无植物单元的4倍,证明植物的存在可以增强湿地单元内土壤微生物对有机物的去除能力。     

Protein and amino acid composition of the tergal gland secretions ofBlatta orientalis andEurycotis floridana (Dictyoptera: Blattidae)

Summary Nymphs and adult females ofBlatta orientalis and nymphs ofEurycotis floridana produce a proteinaceous sticky secretion which accumulates on the last abdominal tergites. The proteic patterns do not differ between individuals of the same species. HPLC analyses show that all the common amino acids are found in both species, aspartic and glutamic acids representing 24 to 37% of the total amount of amino acids. InB. orientalis, glutamic acid is the more abundant amino acid whereas inE. floridana it is the aspartic acid. The secretion appears and accumulates rapidly on isolated insects. Behavioural assays revealed that these secretions have a defensive role.