Trisomy 12 mosaicism in phenotypically normal fetuses following prenatal detection

We report three cases of amniocentesis in which mosaicism for trisomy 12 was detected in two or more independent cultures. The parents elected to terminate the pregnancy in all three cases. Follow-up studies in two of the cases confirmed the mosaicism in fetal tissues (in subcutaneous tissue in one case; in fetal lung in the other), but not in blood. No fetal anomalies were evident by ultrasound or at autopsy. These results along with other reported cases demonstrate the difficulty in counselling for mosaic trisomy 12.     

Concentration of some elements in the hair of cattle as an indicator of contamination by air pollutant deposition on grass

Some 20 elements were determined in cow hair sampled in farms located in various industrial and rural zones of Belgium. Apart from the well-documented dependence of hair contamination as a function of age, the most characteristic feature observed in this study is that the high correlations existing between concentrations of some elements in cow hair provide inter-element ratios which significantly vary from one farm to another. These variations parallel the variations observed in the air pollutants deposited on grass while the inter-element ratios remain almost constant in the soils of all the sampling sites. As a consequence, it is proposed that elemental deposition on pastures is the main source of contamination of cattle by these elements, at least in the rural sites of industrialized countries such as Belgium.     

Biological oxidation of arsenite: batch reactor experiments in presence of kutnahorite and chabazite

Arsenic represents a threat to all living organisms due to its toxicity which depends on its speciation. This element is carcinogenic, teratogenic and is certainly one of the most important contaminants affecting millions of people around the world. Abiotic and biotic processes control its speciation and distribution in the environment. We have previously shown that a new bacterial strain named ULPAs1 performed oxidation of As(III) (1.33 mM) to As(V) in batch cultures. In order to develop new methods to remove arsenic from contaminated effluents or waste, by bacterial oxidation of As(III) to As(V) followed by its sorption, the conservation of oxidative properties of ULPAs1 was investigated when cultivated in batch reactors in the presence of two solid phases, chabazite and kutnahorite, already used as microorganisms immobilizing materials in biological remediation processes. In parallel, the retention efficiency of these solid phases toward arsenic ions and particularly arsenate was studied. Pure quartz sand was used as a reference material. Kutnahorite efficiently sorbed As(V), chabazite alone performed As(III) oxidation and pure quartz sand did not sorb arsenic at all. The arsenite oxidative properties of ULPAs1 were conserved when cultivated in the presence of quartz or chabazite.     

Micromorphology and ultrastructure of Caribbean sclerosponges

Fine structural analysis of living tissue of the sclerosponges Ceratoporella nicholsoni (Hickson) and Stromatospongia norae Hartman, collected near Discovery Bay, Jamaica, between 1984 and 1986, was carried out using transmission and scanning electron microscopy (TEM and SEM). The thick dermal membrane of these sponges is covered by exopinacocytes having a T shape in sections perpendicular to the surface. A dense, complex glycocalyx is produced at the surface of these cells. Choanocyte chambers are diplodal and unusually small. The inhalant and exhalant canals of both species are characterized by the presence of valvules, made by transverse lamellipodial processes of the endopinacocytes lining them. An abundant and diversified bacterial community occupies almost 20% of the mesohyl. A single layer of active basopinacocytes lines the mesohyl at the interface between the living tissue and the aragonitic skeleton. Basopinacocytes are presumed to be precursors of the irregular fibrillar organic matrix found in the aragonitic skeleton. Sclerocytes and spongocytes are abundant in the vicinity of the siliceous spicules. Typical lophocytes releasing smooth collagen fibrils are common in the dermal membrane as well as in the choanosome where they can be grouped in bundles. Uniquely, C. nicholsoni elaborates rough intercellular fibrils characterized by periodically spaced thickenings. The endolithic algae Ostreobium sp. is present in the most apical zones of the aragonitic skeleton, but does not seem to interfere with its development. The striking micromorphological resemblances between both species are discussed and compared to demosponges.Contribution no. 472 from the Discovery Bay Marine Laboratory, University of the West Indies, Discovery Bay, Jamaica, West Indies     

Evaluation procedures for restored land

Release of land for mineral extraction is often dependent on the quality of the restoration which can be achieved. It follows, therefore, that some means of judging the success of restoration is required, especially where restoration is an agricultural after use.In order to assess whether land has been well restored it is therefore necessary to know what the physical characteristics of the land were before mineral extraction took place, what changes are likely to have occurred to the land and soil as a result of mineral extraction, and lastly whether the physical characteristics of the land are as good as when the land was last used for agriculture. Most permissions however, were granted before there was a requirement to record pre-site conditions so it is impossible to know what the site was like when it was last used for agriculture. Furthermore, this paper will argue that land quality is only one factor which should be considered in assessing the quality of restored land, other factors for example, visual integration, farm management must also be taken into consideration. This paper will outline the existing evaluation procedures used by the Ministry of Agriculture, Fisheries & Food and Minerals Planners and suggest developing an evaluation procedure which considers various dimensions of restored land namely soil and land quality, visual integration and the management and productivity of restored land. This evaluation procedure has been applied to seventeen study sites of sand and gravel pits. The paper will indicate whether the evaluation procedure successfully classified these sites or not.     

Soil and plant characteristics as determining factors in site selection for surface coal mine reclamation

Four vegetative associations occur on surface mines located in Mercer County, Pennsylvania. Seventeen different species of grasses and legumes and 30 different species of trees and shrubs were evaluated for their ability to become established and control erosion on surface mines. The amount of organic matter and soil moisture are the principle factors regulating the establishment of vegetative cover on surface mines. Those species possessing a fibrous root system are better able to adapt for erosion control than tap rooted species. Likewise, shrubs such as bristley locust (Robina hispida) and Silver Bush or Autumn Olive (Elaeagnus umbellata) that will produce shoots when a root becomes exposed due to erosion are better adapted for erosion control than other species. The methods and species utilized during reclamation will determine, at least in part, the future use of the land and should establish conditions for natural succession to occur.This study was supported by funds from the National Geographical Society and the Office of Water Resources, U.S. Department of Interior.     

Antimicrobial activities of marine sponges from French Polynesia and Brittany

Extracts from marine sponges collected in French Polynesia and along the Brittany coast (France) have been tested for antibacterial and antifungal activity. The bioactity is concentrated in Dendrilla sp., Homaxinella trachys, Hyrtios eubamma, Verongia aerophoba and Phakellia ventilabrum. The compound responsible for the activity of H. eubamma has been identified as puupehenone, while that of P. ventilabrum is due to a new sesquiteprenoid isonitrile.This study forms part of the Thèse 3e cycle of Ph. Amade, Université de Bretagne Occidentale     

Trisomic pregnancies have normal human chorionic gonadotropin bioactivity

Sera from women carrying either chromosomally normal or aneuploid fetuses in the first half of pregnancy were assayed for human chorionic gonadotropin (hCG) bioactivity in order to determine whether differences might provide the basis for a useful antenatal screen for aneuploidy. A mouse uterine weight assay was used to assess hCG bioactivity in sera from 35 patients undergoing chorionic villus sampling (12 normal pregnancies and 23 trisomic pregnancies) and in sera from 18 patients undergoing elective second-trimester abortion (12 presumed normal pregnancies, 3 trisomic pregnancies, and 3 pregnancies with neural tube defects). The hCG bioactivity to immunoactivity (B:I) ratio of normal pregnancies progressively decreased from 7.7±1.3 at 4–5 menstrual weeks, to 4.7±0.4 at 9–12 menstrual weeks, to 3.3±0.5 at 16–20 menstrual weeks. There were no significant differences in the B:I ratios between normal and aneuploid pregnancies in either the first-trimester (4.7±0.4 versus 5.2±0.3) or the second-trimester samples (3.3±0.5 versus 2.6±0.3), despite significantly greater hCG concentrations in the trisomic pregnancies. We conclude that while aneuploid pregnancies display dysfunctional regulation of hCG expression, the bioactivity of their hCG is normal and does not appear to form the basis for a useful screen for aneuploidy.