Cornelia de Lange syndrome (CdLS): prenatal and autopsy findings

Cornelia de Lange Syndrome (CdLS) is a multisystem disorder characterized by somatic defects and mental retardation. Prenatal diagnosis of this severe condition is difficult in view of the non-specific ultrasound abnormalities. We report three cases with prenatally suspected CdLS based on the ultrasound findings as well as low PAPP-A detected on first trimester screening in one case, and the results of the autopsy and the NIPBL gene mutation analysis. Copyright © 2009 John Wiley & Sons, Ltd.     

Using diatoms to assess the impacts of prehistoric, pre-industrial and modern land-use on Danish lakes

The impact of contemporary agriculture on Danish lakes is acknowledged to be extreme. In particular, high loading of nutrients from agricultural soils contributes to the eutrophic conditions found in many of Denmark’s lakes. Palaeolimnological studies have shown that human disturbance of the Danish landscape since the introduction of agriculture around 6,000 years ago has had a major impact on lake ecosystems. The European Union’s Water Framework Directive requires an evaluation of reference conditions for lakes, the conditions expected with only minimal human impact. Monitoring data and palaeolimnological studies of Danish lakes demonstrate that many of the most detrimental effects of eutrophication have been experienced in recent decades. A new study has suggested that the reference status for Danish lakes may be set to the status in ad 1850–1900, probably providing attainable, realistic restoration targets for many sites. The aims of this study were to explore the impacts of past and contemporary land-use on Danish lakes, and to consider how appropriate the use of 1850 as a date to define reference status is for these sites. Catchment land-cover data for ad 1800, taken from historical maps, and sedimentary diatom assemblages of the same age, from dated sediment cores, were used to assess the impact of pre-industrial land-use on 20 Danish lakes. Analysis of contemporary land-cover data and surface-sediment diatom assemblages for the 20 sites was also made. In-lake total phosphorus (TP) concentrations were estimated using the sedimentary diatom assemblages and an existing calibration dataset for Danish lakes. The percentage of the lake catchment that was agricultural land in ad 1800 explained 8.8% of the total variation in the diatom data. The land-cover variables ‘built-up areas’ and ‘plantations’, together explained 16.9% of the variation in the diatom data for the modern samples. Diatom-inferred TP concentrations were high for both ad 1800 (mean 112 μg TP L⁻¹) and the present (mean 122 μg TP L⁻¹), the latter estimates reflecting efforts in recent decades to reduce nutrient loading to Danish lakes following very high levels of nutrient enrichment post-1950. The data presented highlight the impact that human activities 200 years ago, particularly agriculture, had on Danish lake systems. The long cultural history and major anthropogenic disturbance of the Danish landscape mean that true reference conditions for lakes (or ‘baseline’ conditions, those found prior to human impacts) can be found only by considering century to millennial timescales.     

Modelling Easily Biodegradability of Materials in Liquid Medium-Relationship Between Structure and Biodegradability

In the present project, twenty materials (e.g., polyhydroxybutyrate-hydroxyvalerate, polycaprolactone, cellulose acetate, polyacticacid, polyethylene), representing varied biodegradability levels were studied. An aerobic respirometric test, based on the CEN Draft, was setup. The biodegradability of each plastic film was evaluated by measuring the percentage of carbon converted into CO₂ during 35 days. The values of the CO₂ production were plotted versus days as a cumulative function. In order to reduce its number of points, the cumulative curve was modeled using a sigmoïd function (Hill sigmoïd). This model was compared to one found in the literature. A _i ² test showed that the biodegradation curve was more accurately fitted with the model than the previous one. Three kinetic parameters were determined by this Hill model: one represents the maximal percentage of carbon converted into CO₂, the second the half-life time in days of the degrading part of the material and the third one the curve radius.In addition, the following analyses were carried out on each sample: elemental analysis, thickness, hydrophobicity and surface free energy measurements. In order to compress the information and to keep only relevant pieces, these parameters were submitted to a Principal Component Analysis. PCA found linear combinations of variables that describe major trends in the data. The two principal components which separate groups of materials were closely related to a chemical and a physical axis respectively. Materials showing a high biodegradability were related to high oxygen (and nitrogen) contents and low hydrophobicity: Material thickness did not influence the likeliness to biodegradability described by the maximum biodegradation rate. Finally, this study established the correlation between the biodegradation and the structure of biopolymers.     

Atmospheric Deposition on Swiss Long-Term Forest Ecosystem Research (LWF) Plots

Atmospheric deposition of the major elements was estimated from throughfall and bulk deposition measurements on 13 plots of the Swiss Long-Term Forest Ecosystem Research (LWF) between 1995 and 2001. Independent estimates of the wet and dry deposition of nitrogen (N) and sulfur (S) on these same plots were gained from combined simplified models. The highest deposition fluxes were measured at Novaggio (Southern Switzerland), exposed to heavy air pollution originating from the Po Plain, with throughfall fluxes averaging 29 kg ha^–1 a^–1 for N and 15 kg ha^–1 a^–1 for S. Low deposition fluxes were measured on the plots above 1800 m, with throughfall fluxes lower than 4.5 kg ha^–1 a^–1 for N and lower than 3 kg ha^–1 a^–1 for S. The wet deposition of N and S derived from bulk deposition was close to the modeled wet deposition, but the dry deposition derived from throughfall was significantly lower than the modeled dry deposition for both compounds. However, both the throughfall method and the model yielded total deposition estimates of N which exceeded the critical loads calculated on the basis of long-term mass balance considerations. These estimates were within or above the range of empirical critical loads except above 1800 m.     

Human exposure, health hazards, and environmental regulations

United States environmental regulations, intended to protect human health, generally fail to address major sources of pollutants that endanger human health. These sources are surprisingly close to us and within our control, such as consumer products and building materials that we use within our homes, workplaces, schools, and other indoor environments. Even though these indoor sources account for nearly 90% of our pollutant exposure, they are virtually unregulated by existing laws. Even pollutant levels found in typical homes, if found outdoors, would often violate federal environmental standards. This article examines the importance of human exposure as a way to understand and reduce effects of pollutants on human health. Results from exposure studies challenge traditional thinking about pollutant hazards, and reveal deficiencies in our patchwork of laws. And results from epidemiological studies, showing increases in exposure-related diseases, underscore the need for new protections. Because we cannot rely solely on regulations to protect us, and because health effects from exposures can develop insidiously, greater efforts are needed to reduce and prevent significant exposures before they occur. Recommendations include the development and use of safer alternatives to common products, public education on ways to reduce exposure, systematic monitoring of human exposure to pollutants, and a precautionary approach in decision-making.     

An ecologically oriented database to guide remediation and reuse of contaminated sites

This article presents a database developed to determine the potential reuse of contaminated sites for primarily ecologically and culturally based activities. The database consists of 172 quantitative and qualitative measures of on‐site land suitability, ecological, cultural, and recreational value, and off‐site suitability, economic, and demographic information. Using sites owned by the U.S. Department of Energy (DOE) as a case study, the article evaluates the quality of available data and suggests ways of using it for planning ecologically sensitive remediation activities and future land use. This type of database can be developed and used by anyone who needs to select, review, or evaluate site remediation and future land use options. Also discussed are the challenges associated with compiling and using data that has been generated by many sources over several years. © 2003 Wiley Periodicals, Inc.