Prenatal diagnosis of autosomal recessive osteopetrosis,infantile type,by X-ray evaluation

Prenatal diagnosis for infantile osteopetrosis was attempted during the third pregnancy of a first-cousin marriage whose family history revealed an affected previous child. At the 25th week of pregnancy, fetal X-ray evaluation revealed marked sclerosis of osteopetrotic bone and metaphyseal splaying and clubbing of both femurs. The pregnancy was terminated and repeated X-rays and histopathological examination of fetal bone (femur) confirmed the diagnosis.     

Biotransformation of phenylurea herbicides by a soil bacterial strain, Arthrobacter sp. N2: structure, ecotoxicity and fate of diuron metabolite with soil fungi

In order to assess the influence of the aromatic substitution on the ability of a soil bacterial strain, Arthrobacter sp. N2, to degrade phenylurea herbicides, biotransformation assays were performed in mineral medium with resting cells of this soil bacterial strain on three phenylurea herbicides (diuron, chlorotoluron and isoproturon). Each herbicide considered, led to the formation of only one metabolite detected by HPLC analysis. After isolation, the metabolites were identified by NMR and MS, as the corresponding substituted anilines. According to the Microtox test (realized on the bacterium Vibrio fischeri), these metabolites presented non-target toxicity far more important (up to 600 times higher for 4-isopropylaniline) than the parent molecule. For isoproturon and chlorotoluron, the amount of substituted anilines obtained at the end of the biotransformation was very low, whereas the biotransformation of diuron into 3,4-dichloroaniline was almost quantitative. In this last case, the degradation product accumulated in the medium. In soil, other microorganisms are present that might degrade it. So the biotransformation of 3,4-dichloroaniline was then tested with four fungal strains: Aspergillus niger, Beauveria bassiana, Cunninghamella echinulata var. elegans and Mortierella isabellina. The aniline was further transformed with all the microorganisms tested. Only one metabolite was detected by HPLC analysis and after isolation, it was identified to be 3,4-dichloroacetanilide. This acetylated compound led to biological effects less important on V. fischeri than 3,4-dichloroaniline. These results stress the importance of identifying the degradation products to assess the impact of a polluting agent. Indeed, the pollutant may undergo transformation yielding compounds more toxic than the parent molecule.     

Biological Air Quality Monitoring: a Review

Air quality monitoring is currently ensured by captors measuring few physicochemical parameters, then they cannot evaluate unforeseen compounds and the interaction effects of pollutants. On the contrary, the use of bioindicators can answer these problems. Among them, plants are used in two ways:1) Passive bioindicators: trees, lichens and mosses are used to determine the distribution and even the contaminants long-term effects on vast zones and, possibly, the concentrations of pollutants to which they were exposed.2) Active bioindicators: tobacco and mosses make available the defective zones in plants and enable determination of deposition fluxes.Moreover, techniques based on biomarkers identification should increase the answer's sensitivity. However, the plants present the disadvantage of being unable to provide a response in a time lapse comparable with that of the on-line analysers. Lastly, the development of tools using animal cells should allow, in the near future, to measure the total polluting load under conditions close to those of the routine techniques. Then, the real impact of the contaminant on public health could be approached.     

Long-Term Maintenance of Rapid Atrazine Degradation in Soils Inoculated with Atrazine Degraders

Two different microbial communities able to degrade atrazine (atz) were inoculated in four different soils. The most critical factor affecting the success of inoculation was the soil pH and its organic matter (OM) content. In two alkaline soils (pH > 7), some inoculations led immediately to a strong increase of the biodegradation rate. In a third slightly acidic soil (pH = 6.1), only one inoculum could enhance atz degradation. In a soil amended with organic matter and straw (pH = 5.7, OM = 16.5%), inoculation had only little effect on atz dissipation on the short as well as on the long-term. Nine months after the microflora inoculations, atz was added again and rapid biodegradation in all alkaline inoculated soils was recorded, indicating the long-term efficiency of inoculation. In these soils, the number of atz degraders was estimated at between 6.5 × 10³ and 1.5 × 10⁶ (g of soil)^-1, using the most probable number (MPN) method. Furthermore, the presence of the atz degraders was confirmed by the detection of the gene atzA in these soils. Denaturing gradient gel electrophoresis (DGGE) analysis of the 16S rDNA genes indicated that the inoculated bacterial communities had little effect on the patterns of the indigenous soil microflora.     

Association of spinal deformities with heavy metal bioaccumulation in natural populations of grass goby, Zosterisessor ophiocephalus Pallas, 1811 from the Gulf of Gabès (Tunisia)

The present study illustrates an analysis of spinal deformities associated with metal accumulation in natural populations of Zosterisessor ophiocephalus derived from polluted (S1) and unpolluted (S2) areas in the Gulf of Gabès in Tunisia. Three basic types of spinal deformities were detected: kyphosis, scoliosis and lordosis. These basic deformities frequently co-occur. Spinal deformities were observed in 10.72% of the total examined fish (n = 494). Deformed fish were 3.85 times more frequent in S1 than in S2. In both sexes, the highest occurrence of deformities was observed in the 111-120 mm class decreasing thereafter with fish length. Hepatic concentrations of cadmium (Cd), copper (Cu) and zinc (Zn) were significantly higher in Z. ophiocephalus from S1 than those from S2. Comparisons between fish in each site showed that liver concentrations of Cd and Zn were significantly higher in deformed fish than in normal fish. The relationship between metals accumulation and observed spinal deformities as well as the suitability of this kind of studies for environmental monitoring are discussed.     

Kinetic degradation processes of butyl- and phenyltins in soils

The degradation of organotin compounds (OTC) in agricultural and forest soils is studied in sandy soil samples. Individual experiments involving the three butyl- and the three phenyltins were carried out during 90 d in controlled conditions (darkness, 28 degrees C, aerobic conditions, 13% moisture) and with spiking concentration representative of environmental levels (20-50 micrg(Sn) kg(-1)). After the validation of first-order degradation kinetic model, mechanisms involved throughout the study were considered. Degradation pathways are proposed for butyl- and phenyltins and discussed according to literature data. The degradation of mono- (MBT, MPhT), di-organotins (DBT, DPhT) and TBT is clearly identified as a single successive loss of an organic group whereas TPhT is directly degraded to MPhT. The half-life times were dependent on their substitution degree, ranging from 24 (TPhT) to 220 (MBT) d. The less substituted the OTC is, the more persistent it is. In the range 4.3-5.7, pH does not seem to influence OTC degradation under the present operating conditions. Finally this study shows the significant persistence in soil samples in our experimental conditions for most of studied organotins and highlights the potential impact on soil quality.     

Maternal provisioning for larvae and larval provisioning for juveniles in the toxopneustid sea urchin <Emphasis Type="Italic">Tripneustes gratilla</Emphasis>

Lipid and protein biochemistry of eggs (84 μm in diameter), embryos and early larvae of the tropical echinoid Tripneustes gratilla (Linnaeus 1758) were quantified to determine how maternal provisions are used to fuel development of the echinopluteus. The eggs contained a mean of 30.82 ng lipid and 87.32 ng protein. Energetic lipids were the major lipid component (55.52% of total lipid) with the major class being triglyceride (TG: mean 15.9 ng, 51.58% of total). Structural lipid was dominated by phospholipid (PL: mean 11.18 ng, 36.26% of total). Early embryogenesis was not a major drain on egg energetic lipid and protein. Development of the functional feeding larva used ca. 50% of initial egg energetic lipid and most of this was TG. Maternal TG was still present in the 8-day echinoplutei and it was estimated that this energetic lipid would be depleted in unfed larvae by day 10. There was no change in PL. In a separate experiment lipid biochemistry of rudiment stage larvae and early developing juveniles were quantified to determine how lipids are used during metamorphosis. Fed larvae accumulated lipid (mean 275.49 ng) with TG and PL being the major energetic and structural lipids, respectively. Larval lipid stores were not appreciably depleted by metamorphosis and so were available for the early benthic stage juvenile. Juveniles started their benthic existence with 314 ng total lipid (TG: mean 46.84 ng, 14.9% of total, PL: mean 137.51 ng, 43.67% of total). Nile Red histochemistry and histology showed that the stomach serves as a nutrient storage organ and, that lipid stores accrued by larvae sustain developing juveniles for up to 4 days post settlement. Triglyceride supported both non-feeding stages of development and the prefeeding larval and perimetamorphic benthic stage. In this first study of lipid stores in settlement stage echinoderm larvae, we show that T. gratilla larvae sequester the same major energetic lipid (TG) to support the early juvenile that the female parent provided them to fuel early development.     

Towards a framework for assessment and management of cumulative human impacts on marine food webs

Effective ecosystem‐based management requires understanding ecosystem responses to multiple human threats, rather than focusing on single threats. To understand ecosystem responses to anthropogenic threats holistically, it is necessary to know how threats affect different components within ecosystems and ultimately alter ecosystem functioning. We used a case study of a Mediterranean seagrass (Posidonia oceanica) food web and expert knowledge elicitation in an application of the initial steps of a framework for assessment of cumulative human impacts on food webs. We produced a conceptual seagrass food web model, determined the main trophic relationships, identified the main threats to the food web components, and assessed the components’ vulnerability to those threats. Some threats had high (e.g., coastal infrastructure) or low impacts (e.g., agricultural runoff) on all food web components, whereas others (e.g., introduced carnivores) had very different impacts on each component. Partitioning the ecosystem into its components enabled us to identify threats previously overlooked and to reevaluate the importance of threats commonly perceived as major. By incorporating this understanding of system vulnerability with data on changes in the state of each threat (e.g., decreasing domestic pollution and increasing fishing) into a food web model, managers may be better able to estimate and predict cumulative human impacts on ecosystems and to prioritize conservation actions.