Early prenatal diagnosis of genetic microcephaly

We report a new case of prenatal diagnosis of recessive microcephaly by ultrasound examination allowing termination of pregnancy at 25 weeks gestation.     

Two-compartment model of radionuclide accumulation into marine organisms. I. Accumulation from a medium of constant activity

The interpretation of kinetics of radionuclide accumulation into biological organisms can be performed by using the well-known multicompartment models. The application of a two-compartment model in the interpretation of radionuclide accumulation into marine organisms, when this does not markedly deplete the medium, is considered. It has been found that most of the loss experiments cannot be interpreted without the use of uptake data. The agreement between the uptake and loss parameters is discussed. Explicit expressions for different kinds of two-compartment models are evaluated. The interpretation of irreversible and other special cases is proposed.     

Transformations of <Emphasis Type="Italic">n</Emphasis>-alkanes from petroleum pollutants in alluvial groundwaters

Investigations presented in this paper were aimed at defining the alterations of n-alkane composition in cases of oil-polluted alluvial sediments. Therefore, oil-polluted groundwater samples, taken in five different time intervals during a period of 28 months, were investigated. Samples of alluvial sediments were taken from two boreholes within an oil refinery at Pancevo, Yugoslavia. In both boreholes significant alterations with characteristic degradation of "oil" n-alkanes with no odd- or even-member predominance were observed, as well as subsequent synthesis of new ones with pronounced even-member predominance, and with maxima at C₁₆ and C₁₈. Since no additional contamination of boreholes was observed by analyses of steranes and triterpanes, the observed changes can only be attributed to microbial activity. It is assumed that for the degradation of oil n-alkanes, as well as for the synthesis of "new" n-alkanes, algae such as dinoflagellates are responsible. This assumption was confirmed by identification of n-alcohols with even-member predominance (C₁₄–C₂₀), by identification of cholesterol, as well as of n-fatty acids with even-member predominance (C₁₄–C₁₈) in the extract with n-alkane even-member predominance. Electronic Publication     

Metabolic fate of aromatic amines in the mussel Mytilus galloprovincialis

The postmitochondrial fraction of the digestive gland from the marine mussel Mytilus galloprovincialis possesses FAD-containing monooxygenase (EC 1.14.38) but lacks cytochrome P-450 dependent benzo(a)pyrene monooxygenase (EC 11.4.14.1). This is also evidenced by the ability of the mussel preparation to activate carcinogenic aromatic amines, but not carcinogenic benzo(a)pyrene, to Salmonella typhimurium TA 98 mutagens. This metabolic activity is NADPH dependent. Mussel digestive gland postmitochondrial fraction also possesses the enzymes needed for the detoxicating part of the aromatic amine metabolism: UDP-glucuronyl transferase (EC 2.4.1.17) and -glucuronidase (EC 3.2.1.31). Under the experimental conditions used here, this aromatic amine metabolic pathway converts up to 8% of 2-acetylamino(9-¹⁴C)fluorene, but not (G-³H)benzo(a)pyrene, to water soluble glucuronides. Glucuronic acid stimulates the formation of these glucuronides. The metabolites liberated from these glucuronides by the -glucuronidase treatment could be converted to TA 98 strain mutagens by the carp liver postmitochondrial fraction, but not by the mussel's digestive gland preparation. The presence of such a selective potential for the bioactivation and detoxication of aromatic amines, and not polycyclic aromatic hydrocarbons, in the marine invertebrate(s) may bring new insight to our understanding of the effects and the fate of carcinogens in the marine environment.