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The use of imaging procedures brings with it legal consequences at different levels and in various relationships. As far as the generation of knowledge by means of imaging procedures is concerned, the problem of so-called incidental findings even now already demands a legally sound management in daily routine. Similarly, the use of imaging procedures in ongoing legal proceedings is of current relevance in cases when expert witnesses make use of the appropriate technologies for the formulation of their expertise. In contrast, lie detectors are far from any practical utility for forensic purposes. The major challenge in the next few years will be to investigate the scientific-medical knowledge gained from brain research concerning possible legal implications and to develop on this basis a practice-relevant and, if at all possible, proactive regulatory model.

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Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems, from arctic and boreal systems to tropical forests. Current thinking on the mechanisms of N deposition effects on plant diversity, the global distribution of G200 ecoregions, and current and future (2030) estimates of atmospheric N-deposition rates are then used to identify the risks to plant diversity in all major ecosystem types now and in the future. This synthesis paper clearly shows that N accumulation is the main driver of changes to species composition across the whole range of different ecosystem types by driving the competitive interactions that lead to composition change and/or making conditions unfavorable for some species. Other effects such as direct toxicity of nitrogen gases and aerosols, long-term negative effects of increased ammonium and ammonia availability, soil-mediated effects of acidification, and secondary stress and disturbance are more ecosystem- and site-specific and often play a supporting role. N deposition effects in mediterranean ecosystems have now been identified, leading to a first estimate of an effect threshold. Importantly, ecosystems thought of as not N limited, such as tropical and subtropical systems, may be more vulnerable in the regeneration phase, in situations where heterogeneity in N availability is reduced by atmospheric N deposition, on sandy soils, or in montane areas. Critical loads are effect thresholds for N deposition, and the critical load concept has helped European governments make progress toward reducing N loads on sensitive ecosystems. More needs to be done in Europe and North America, especially for the more sensitive ecosystem types, including several ecosystems of high conservation importance. The results of this assessment show that the vulnerable regions outside Europe and North America which have not received enough attention are ecoregions in eastern and southern Asia (China, India), an important part of the mediterranean ecoregion (California, southern Europe), and in the coming decades several subtropical and tropical parts of Latin America and Africa. Reductions in plant diversity by increased atmospheric N deposition may be more widespread than first thought, and more targeted studies are required in low background areas, especially in the G200 ecoregions.

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Field observations and experimental data of effects of nitrogen (N) deposition on plant species diversity have been used to derive empirical critical N loads for various ecosystems. The great advantage of such an approach is the inclusion of field evidence, but there are also restrictions, such as the absence of explicit criteria regarding significant effects on the vegetation, and the impossibility to predict future impacts when N deposition changes. Model approaches can account for this. In this paper, we review the possibilities of static and dynamic multispecies models in combination with dynamic soil-vegetation models to (1) predict plant species composition as a function of atmospheric N deposition and (2) calculate critical N loads in relation to a prescribed protection level of the species composition. The similarities between the models are presented, but also several important differences, including the use of different indicators for N and acidity and the prediction of individual plant species vs. plant communities. A summary of the strengths and weaknesses of the various models, including their validation status, is given. Furthermore, examples are given of critical load calculations with the model chains and their comparison with empirical critical N loads. We show that linked biogeochemistry-biodiversity models for N have potential for applications to support European policy to reduce N input, but the definition of damage thresholds for terrestrial biodiversity represents a major challenge. There is also a clear need for further testing and validation of the models against long-term monitoring or long-term experimental data sets and against large-scale survey data. This requires a focused data collection in Europe, combing vegetation descriptions with variables affecting the species diversity, such as soil acidity, nutrient status and water availability. Finally, there is a need for adaptation and upscaling of the models beyond the regions for which dose-response relationships have been parameterized, to make them generally applicable.

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Long-range transboundary air pollution has caused severe environmental effects in Europe. European air pollution abatement policy, in the framework of the UNECE Convention on Long-range Transboundary Air Pollution (LRTAP Convention) and the European Union Clean Air for Europe (CAFE) programme, has used critical loads and their exceedances by atmospheric deposition to design emission abatement targets and strategies. The LRTAP Convention International Cooperative Programme on Modelling and Mapping Critical Loads and Levels and Air Pollution Effects, Risks and Trends (ICP M&M) generates European critical loads datasets to enable this work. Developing dynamic nitrogen flux models and using them for a prognosis and assessment of nitrogen effects remains a challenge. Further research is needed on links between nitrogen deposition effects, climate change, and biodiversity.

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Stem cell procedures could be the starting point for major advances in healthcare. However, it is a very difficult task to define the legal status of human stem cells. The resolution of the legal issues has been hindered by the still early stage of research and development and by scientists' varying assessment of the fundamental differences between several types of stem cells and of the potential of these types. Nevertheless, on 30 January 2002 the German Parliament (Bundestag) paved the way for the import of pluripotent embryonic cells under the following basic conditions: The import is restricted to stem cell lines which already exist; the embryo's parents' informed consent has to be obtained; the research purposes must be high-ranking; the ethical acceptance has to be examined by a high-level ethical committee; and an authorizing authority must license the import. The questions is, whether these requirements meet the practical needs of scientists. However, the European Biotechnology Directive calls for the patentability of stem cell procedures and therefore presents a major incentive for researchers in the field of stem cell technologies.

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Article 20a of the Basic Law, which was most recently modified,provides that "The State, aware of its responsibility for present and future generations, shall protect the natural basis of life and the animals within the framework of the constitutional order through the legislature and, in accordance with the law and principles of justice, the executive and the judiciary." However, this amendment of the constitution does not have adverse effects on researchers' freedom to carry out scientific experiments on animals. According to the jurisdiction of the German Federal Constitutional Court, the basic right of scientific freedom (Article 5 paragraph 3 of the Basic Law) has to be protected from any influencing control of the state. In addition, Article 20a of the Basic Law is a so called state goal and therefore presents a mere guideline for discretionary decisions. Because of that, the individual also lacks locus standi to enforce it. As a consequence, weighing up the legal aspects comes to the conclusion, that the very core of scientific freedom takes precedence over the new state goal aiming at animal protection on the constitutional level.

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Ubiquinol-10 and ubiquinone-10 were measured in plasma of patients with several pathologies known to be associated with increased oxidative stress. Plasma ubiquinol-10, expressed as a percentage of total ubiquinol-10 + ubiquinone-10, was found to be significantly lower in hyperlipidaemic patients and in patients with liver diseases than in age-matched control subjects. In contrast, no decrease in ubiquinol-10 was detected in plasma of patients with coronary heart disease and Alzheimer's disease. Except for ubiquinol-10, no other lipophilic antioxidant was found to be decreased in patients with liver diseases. These data suggest that the level of ubiquinol-10 in human plasma may serve as a marker for liver dysfunction, reflecting its diminished reduction by the liver rather than increased consumption by oxidants.

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Oxidative theory of atherosclerosis implies that plasma levels of lipophilic antioxidants might serve as indicators of lipoprotein oxidation in the arterial wall and as markers of the development of atherosclerosis. However, it is unknown whether the measurement of plasma antioxidants is able to reflect atherogenesis or its risk. In order to assess whether the levels of lipophilic antioxidants in human plasma can discriminate between subjects with and without atherosclerosis, we measured the lipophilic antioxidants alpha-tocopherol, gamma-tocopherol, alpha-carotene, beta-carotene and ubiquinol-10 in plasma of 34 patients with coronary heart disease (CHD) and in 40 control subjects. We found that alpha-carotene and gamma-tocopherol were significantly lower in plasma of CHD patients compared to controls. This decrease was significantly independent of whether the antioxidants were expressed as its absolute amounts in plasma (P < 0.001 for alpha-carotene, and P = 0.001 for gamma-tocopherol) or normalized to plasma lipids (P < 0.001 for both). In contrast, beta-carotene was only lower in plasma of CHD patients in comparison to controls, when normalized to the lipids (P = 0.02). Independent contributions of different parameters to the variation in these plasma antioxidants were estimated using multiple regression approach. The analysis showed that both the decrease in alpha-carotene and the decrease in gamma-tocopherol were significantly associated only with the presence of CHD (P < 0.001 for each regression), while the decrease in beta-carotene was significantly related to the presence of hyperlipidaemia (P < 0.001). In striking contrast, no decrease in plasma alpha-tocopherol and ubiquinol-10 was detected in the patient group independently of how these antioxidants were expressed. These data suggest that plasma levels of alpha-carotene and gamma-tocopherol may represent markers of atherosclerosis in humans. Measuring these antioxidants may be of clinical importance as a practical approach to assess atherogenesis and/or its risk.

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Lipoprotein oxidation induced in vitro in whole plasma is expected to represent a more relevant model of the lipoprotein oxidation in the arterial wall than the in vitro oxidation of single isolated lipoproteins, e.g. low density lipoprotein (LDL). However, it remains unclear, how lipoprotein oxidation occurring in plasma is related to chemical composition and properties of the latter as well as to those of individual plasma lipoproteins. The present study was undertaken to characterize, how different constituents of human plasma contribute to the oxidizability of plasma lipoproteins oxidized directly in plasma samples. Oxidizability of plasma lipoproteins was assessed as oxidizability of whole heparin plasma and was measured spectrophotometrically as an increase in absorbance at 234 nm. To relate plasma oxidizability to its chemical composition and properties, plasma hydrophilic and lipophilic antioxidants, fatty acids, total lipids and TRAP were measured. To relate plasma oxidizability to the properties of individual lipoproteins, chemical composition and oxidizability were evaluated for LDL. We found that the oxidation kinetics of heparin plasma (diluted 150-fold and oxidized by 50 microM Cu2+) was characterized by three consecutive phases similar to the lag-, propagation and decomposition phases of LDL oxidation. Plasma oxidizability measured as different characteristics of these phases correlated negatively with plasma initial SH-groups, albumin, ascorbate, bilirubin, alpha-tocopherol, ubiquinol-10, free cholesterol, monounsaturated and saturated fatty acid content and positively with plasma initial total cholesterol, cholesterol ester and polyunsaturated fatty acid content. Plasma oxidizability measured as a rate of conjugated diene accumulation after different periods of oxidation correlated negatively with plasma initial albumin, urate, alpha-carotene and beta-carotene content. A positive correlation between oxidizabilities of whole plasma and LDL (isolated from the same plasma samples and oxidized by 14 mol Cu2+/mol LDL) was found. These data show that the oxidizability of plasma samples is critically determined by their chemical composition. They also suggest that the plasma oxidizability measured as an increase in absorbance at 234 nm may be used as a practical measure of the oxidizability of plasma lipoproteins.

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Ubiquinol-10, the reduced form of ubiquinone-10 (coenzyme Q10), is a potent lipophilic antioxidant present in nearly all human tissues. The exceptional oxidative lability of ubiquinol-10 implies that it may represent a sensitive index of oxidative stress. The present study was undertaken to assess the hypothesis that the level of ubiquinol-10 in human plasma can discriminate between healthy subjects and patients who are expected to be subjected to an increased oxidative stress in vivo. Using a newly developed method, we measured plasma ubiquinol-10 in 38 hyperlipidaemic patients with and without further complications, such as coronary heart disease, hypertension, or liver disease, and in 30 healthy subjects. The oxidizability of plasma samples obtained from hyperlipidaemic patients was found to be increased in comparison with control subjects, suggesting that the patients were subjected to a higher oxidative stress in vivo than the controls. Plasma ubiquinol-10, expressed as a percentage of total ubiquinol-10 + ubiquinone-10 or normalized to plasma lipids, was lower in the patients than in controls (P = 0.001 and 0.008, respectively). The proportion of ubiquinol-10 decreased in the order young controls > aged controls > hyperlipidaemic patients without complications > hyperlipidaemic patients with complications (P = 0.003). A negative correlation was found between the proportion of ubiquinol-10 and plasma triglycerides. The hyperlipidaemic patients with hypertension had a lower proportion of ubiquinol-10 than subjects without. When the study population was divided into smokers and non-smokers, plasma ubiquinol-10 was found to be reduced amongst smokers, independently of whether it was expressed as a percentage of total ubiquinol-10 + ubiquinone-10 (P = 0.006) or normalized to plasma lipids (P = 0.009). These data suggest that the level of ubiquinol-10 in human plasma may represent a sensitive index of oxidative stress in vivo especially indicative of early oxidative damage. Measuring plasma ubiquinol-10 can be proposed as a practical approach to assess oxidative stress in humans.

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Lipoprotein oxidation induced in vitro in whole plasma is expected to be a more relevant model of the lipoprotein oxidation in the arterial wall than the in vitro oxidation of single isolated lipoproteins, e.g., low density lipoprotein (LDL). However, it is unclear, whether the oxidizability of whole plasma may serve as an adequate measure of the oxidizability of plasma lipoproteins. We measured the oxidizability of whole plasma diluted 150-fold as an absorbance increase at 234 nm known to reflect the level of conjugated dienes in the samples. Plasma oxidation was induced by Cu(II), 2,2'-azobis-(2-amidinopropane) hydrochloride (AAPH), lipoxygenase or myeloperoxidase+H2O2. Oxidizability of human plasma measured in the presence of Cu(II) was found to correlate with the oxidizability of LDL measured in the common Cu(II)-based LDL oxidation assay. The plasma oxidizability also correlated positively with plasma oxidizable fatty acid and negatively with plasma antioxidant content. Supplementation of human plasma with different antioxidants (albumin, urate, ascorbate, bilirubin, alpha-tocopherol and ubiquinol-10) in vitro decreased its oxidizability. Supplementation of Watanabe heritable hyperlipidaemic rabbits with different antioxidants (vitamin E, ubiquinone-10, probucol, carvedilol) in vivo lowered the oxidizability of rabbit plasma in comparison with rabbits fed standard diet. When plasma from hyperlipidaemic patients with or without coronary heart disease and from age-matched healthy controls was studied, the plasma oxidizability was found to be highest in the patients with coronary heart disease and lowest in the controls. Taken together, these data indicate that the plasma oxidation assay (i) provides information similar to that obtained using the common LDL oxidation assay, (ii) upgrades the latter, taking into account the effect of hydrophilic antioxidants on lipoprotein oxidation and characterizing the oxidizability of all plasma lipoproteins, and (iii) offers important practical advantages, such as fast and simple sample processing, low amount of plasma required and avoidance of artefactual oxidation during lipoprotein isolation. We propose the measurement of plasma oxidizability at 234 nm as an adequate practical index of the oxidizability of plasma lipoproteins.

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