Fetal cardiac anomalies and genetic syndromes

Cardiac anomalies may occur in isolation or can be part of a genetic syndrome. In this article, we describe some of the genetic syndromes commonly associated with cardiac anomalies where there are other sonographic features that may aid accurate prenatal diagnosis. Copyright © 2004 John Wiley & Sons, Ltd.     

Sulphate, Nitrogen and Base Cation Budgets at 21 Forested Catchments in Canada, the United States and Europe

To assess the concern over declining base cation levels in forest soils caused by acid deposition, input-output budgets (1990s average) for sulphate (SO₄), inorganic nitrogen (NO₃-N; NH₄-N), calcium (Ca), magnesium (Mg) and potassium (K) were synthesised for 21 forested catchments from 17 regions in Canada, the United States and Europe. Trend analysis was conducted on monthly ion concentrations in deposition and runoff when more than 9 years of data were available (14 regions, 17 sites). Annual average SO₄ deposition during the 1990s ranged between 7.3 and 28.4 kg ha⁻¹ per year, and inorganic nitrogen (N) deposition was between 2.8 and 13.8 kg ha⁻¹ per year, of which 41–67% was nitrate (NO₃-N). Over the period of record, SO₄ concentration in deposition decreased in 13/14 (13 out of 14 total) regions and SO₄ in runoff decreased at 14/17 catchments. In contrast, NO₃-N concentrations in deposition decreased in only 1/14 regions, while NH₄-N concentration patterns varied; increasing at 3/14 regions and decreasing at 2/14 regions. Nitrate concentrations in runoff decreased at 4/17 catchments and increased at only 1 site, whereas runoff levels of NH₄-N increased at 5/17 catchments. Decreasing trends in deposition were also recorded for Ca, Mg, and K at many of the catchments and on an equivalent basis, accounted for up to 131% (median 22%) of the decrease in acid anion deposition. Base cation concentrations in streams generally declined over time, with significant decreases in Ca, Mg and K occurring at 8, 9 and 7 of 17 sites respectively, which accounted for up to 133% (median 48%) of the decrease in acid anion concentration. Sulphate export exceeded input at 18/21 catchments, likely due to dry deposition and/or internal sources. The majority of N in deposition (31–100%; median 94%) was retained in the catchments, although there was a tendency for greater NO₃-N leaching at sites receiving higher (<7 kg ha^-1 per year) bulk inorganic N deposition. Mass balance calculations show that export of Ca and Mg in runoff exceeds input at all 21 catchments, but K export only exceeds input at 16/21 sites. Estimates of base cation weathering were available for 18 sites. When included in the mass balance calculation, Ca, Mg and K exports exceeded inputs at 14, 10 and 2 sites respectively. Annual Ca and Mg losses represent appreciable proportions of the current exchangeable soil Ca and Mg pools, although losses at some of the sites likely occur from weathering reactions beneath the rooting zone and there is considerable uncertainty associated with mineral weathering estimates. Critical loads for sulphur (S) and N, using a critical base cation to aluminium ratio of 10 in soil solution, are currently exceeded at 7 of the 18 sites with base cation weathering estimates. Despite reductions in SO₄ and H⁺ deposition, mass balance estimates indicate that acid deposition continues to acidify soils in many regions with losses of Ca and Mg of primary concern. The U.S. Government's right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged. The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

Renatal diagnosis of mosaic tetrasomy 12p/trisomy 12p by fluorescent in situ hybridization in amniotic fluid cells: A case report of pallister–killian syndrome

A prenatally detected case of a rare mosaic tetrasomy 12p/trisomy 12p is reported, presenting as the well-known accessory isochromosome 12p and a supernumerary single 12p marker in 17/24 and 6/24 clones of cultured amniotic fluid cells, respectively. The chromosomal nature of both marker chromosomes was investigated in cultured amniotic fluid cells by fluorescent in situ hybridization with various probes: the 12-centromeric probes pa12H8 and D12Z3, a whole chromosome 12 paint, and the chromosome 12p-specific paint M28. DNA analysis revealed a maternal origin of the extra 12p material. After counselling, the parents requested termination of pregnancy. Inspection and autopsy of the fetus revealed many of the dysmorphisms and internal structural abnormalities of the Pallister–Killian syndrome.     

Prenatal diagnosis of a de novo unbalanced translocation (4p + ) following in vitro fertilization

We report herein a de novo unbalanced chromosome translocation in a fetus resulting from in vitro fertilization technology. Prenatal diagnostic analysis of an amniotic fluid revealed a 46,XX,4p+ karyotype. The origin of the extra material on the short arm of chromosome 4 could not be identified by a variety of banding techniques. However, examination of fetal parts did reveal some dysmorphic features.     

Spatial variability of soil phosphorus in relation to the topographic index and critical source areas: sampling for assessing risk to water quality

A measure of soil P status in agricultural soils is generally required for assisting with prediction of potential P loss from agricultural catchments and assessing risk for water quality. The objectives of this paper are twofold: (i) investigating the soil P status, distribution, and variability, both spatially and with soil depth, of two different first-order catchments; and (ii) determining variation in soil P concentration in relation to catchment topography (quantified as the "topographic index") and critical source areas (CSAs). The soil P measurements showed large spatial variability, not only between fields and land uses, but also within individual fields and in part was thought to be strongly influenced by areas where cattle tended to congregate and areas where manure was most commonly spread. Topographic index alone was not related to the distribution of soil P, and does not seem to provide an adequate indicator for CSAs in the study catchments. However, CSAs may be used in conjunction with soil P data for help in determining a more "effective" catchment soil P status. The difficulties in defining CSAs a priori, particularly for modeling and prediction purposes, however, suggest that other more "integrated" measures of catchment soil P status, such as baseflow P concentrations or streambed sediment P concentrations, might be more useful. Since observed soil P distribution is variable and is also difficult to relate to nationally available soil P data, any assessment of soil P status for determining risk of P loss is uncertain and problematic, given other catchment physicochemical characteristics and the sampling strategy employed.     

Discussing why population growth is still ignored or denied

Due to a number of factors outlined in this article, the issue of population growth is excluded from the sustainability discussion. In this article, we explore some of the ethical presumptions that underlie the issues linking population growth and sustainability. Critics argue that action to address population creates social and economic segregation, and portray overpopulation concerns as being “anti-poor,” “anti-developing country,” or even “antihuman.” Yet, de-linking demographic factors from sustainability concerns ignores significant global realities and trends, such as the ecological limits of the Earth, the welfare and long-term livelihood of the most vulnerable groups, future prospects of humanity, as well as the ecosystems that support society.