Browsing by Author "Becker, T."

In summer 2003 we recorded the presence and abundance of alien plant species at 232 sites (107 railway stations and 125 road sites) along mountain passes in the Swiss Alps. The altitudinal distribution of species was related to the current abundance of the species in Switzerland and time since introduction. A total of 155 alien taxa were recorded. Numbers of species per site declined exponentially with altitude, and only a few species were found in the alpine zone (> 2000 m). In contrast, species richness among comparable native taxa appeared to be nearly independent of altitude over the range investigated. Maximum altitude reached by alien species was related positively to both total area occupied in Switzerland and to time since introduction. A comparison of the results with earlier records suggests that many species, particularly those previously restricted to low or intermediate altitudes, have advanced their altitudinal limits over the past few decades. Various hypotheses are presented to explain the declining abundance of alien species with altitude: low-altitude filter effects, low propagule pressure, and genetic swamping of peripheral populations at higher altitudes. However, at present we do not have sufficient evidence to determine the relative importance of these effects. We conclude that invasion into mountain areas such as the Swiss Alps tends to proceed rather slowly, though the process may be accelerated by climatic warming. For this reason, further research to investigate the processes determining how plants invade mountain areas is urgently needed. And more generally, investigations into the distribution of alien species along strong altitudinal gradients may provide valuable insights into the mechanisms driving the spread of alien organisms. (c) 2005 Rubel Foundation, ETH Zurich. Published by Elsevier GmbH. All rights reserved.

Fifty four German dairy farmers answered a questionnaire concerning their attitude towards the impact of grazing on the milk production. Farmers, who provide access to pasture for their cows are not worried, that this could reduce the performance of their cows. This applies to both, grazing farms, where grass still contributes a part to the ration of the cows as well as for farms with highly restricted grazing, where the possible intake of grass is negligible. In contrast to this, farmers with all-year housing assume that grazing would reduce the milk production of cows. We also found that the performance of the cows on grazing farms is significantly lower than the performance of cows on farms with highly restricted grazing or non-grazing farms. Moreover, cows on grazing farms are generally provided with less energ y from maize and concentrates than cows from non-grazing farms and farms with highly restricted grazing. We conclude that farmers with different management systems have different opinions on what they regard as a high milk production. While farmers from grazing farms are content with the milk production they achieve, farmers from non-grazing farms and from farms with highly restricted grazing pursue a higher milk production.

Background: Psoriasis is a genetically complex, chronic inflammatory skin disease. The authors have previously identified a susceptibility locus on chromosome 19p13 (PSORS6). Methods and results: In a follow-up linkage disequilibrium (LD) study in an independent family based cohort, the authors found evidence for association to a newly discovered microsatellite at this locus (D19SPS21, p<5.3x10(-5)). An LD based association scan in 300 trios revealed association to several single, single nucleotide polymorphisms (SNPs) in one LD block. When the authors stratified this cohort for carrying the PSORS1 risk allele at the HLA-C locus, evidence for association became much stronger at single SNP and haplotype levels (p values between 1.0x10(-4) and 8.0x10(-4)). In a replication study of 1114 patients and 937 control individuals, evidence for association was also observed after stratification to the PSORS1 risk allele. In both study groups, logistic regression showed evidence for interaction between the risk alleles at PSORS1 and PSORS6. Best p values for rs12459358 in both study groups remained significant after correction for multiple testing. The associated LD block did not comprise any known genes. Interestingly, an adjacent gene, MUC16, coding for a large glycosylated protein expressed in epithelia and of unknown function, could be shown to be also expressed in tissues relevant for pathogenesis of psoriasis such as skin and thymus. Immunohistochemical analyses of skin revealed focal staining for MUC16 in suprabasal epidermal cells. Further functional studies are required to clarify its potential role in psoriasis and identify the causal variant(s) at this locus. Conclusion: The data establish PSORS6 as a confirmed psoriasis susceptibility locus showing interaction with PSORS1.

The generally positive perception of grazed grassland combines aspects of landscape, aesthetic values, biodiversity and concern for animal welfare. Many consumers are in favor of grazing and there is a rising political interest to support farms, which let their cows graze. In order to understand the motivations and the constraints dairy farmers are facing, 46 German dairy farmers were interviewed. Besides questions concerning factors like farm size, milk yield or number of cows, the farmers were asked about their attitudes towards grazing. Farmers, who let their cows graze, generally judge grazing more positive than farmers from non-grazing-farms. On top of that, they denote their knowledge about grazing as good; farmers from non-grazing farms and from siesta-grazing farms describe their knowledge about grazing management as poor. Grazing farms usually have a greater proportion of grassland that is close to the farm.

Objective: Some phytoestrogens are believed to have selective estrogen receptor modulator (SERM) activity with no action in the uterus but beneficial effects in the hypothalamo/pituitary unit and in the bone and are presently the focus of clinical interest. In the present experiments, the effects of the clinically used Cimicifuga racemosa (CR) extract BNO 1055 in the uterus, in the bone and on serum luteinizing hormone (LH) were compared with the effects of estradiol-17beta (E-2) under acute and chronic conditions in ovariectomized rats. Methods: Ovariectomized rats were treated either acutely (6 h) or chronically (3 months) with E-2 or the CR extract. Gene expression of some estrogen-regulated genes in the metaphysis of the tibia and the uterus was determined. Furthermore, bone mineral density was measured by quantitative computer tomography. Results: When given acutely, both E-2 and the CR extract inhibited LH secretion and slightly stimulated gene expression of IGF-I, collagen-1alpha1, osteoprotegerin and osteocalcin (all osteoblast products), and of tartrate-resistant acid phosphatase (TRAP, an osteoclast product) in the metaphysis of the femur. While E-2 stimulated uterine weight and expression of progesterone receptor (PR), the complement protein (C3) and IGF-I genes, and inhibited gene expression of the estrogen receptor beta (ERbeta) in the uterus, no such effect was observed under acute CR treatment. After chronic application with pelleted food over 3 months E-2 had profound effects in the uterus on weight and gene expression (ERbeta, PR, C3 and IGF-I) which were not seen in the CR-treated animals. Within 3 months after ovariectomy, control rats had lost more than 50% of the metaphyseal bone mass of the tibia, an effect prevented by E2 and partially by CR supplementation. Conclusions: These data confirm the concept that the CR extract BNO 10 5 5 contains as yet unidentified substances with SERM properties which act in the hypothalamo/pituitary unit and in the bone but not in the uterus.

Few data are available concerning the role of risk markers for Alzheimer’s disease (AD) in progression to AD dementia among subjects with mild cognitive impairment (MCI). We therefore investigated the role of well-known AD-associated single-nucleotide polymorphism (SNP) in the progression from MCI to AD dementia. Four independent MCI data sets were included in the analysis: (a) the German study on Aging, Cognition and Dementia in primary care patients (n=853); (b) the German Dementia Competence Network (n=812); (c) the Fundació ACE from Barcelona, Spain (n=1245); and (d) the MCI data set of the Amsterdam Dementia Cohort (n=306). The effects of single markers and combined polygenic scores were measured using Cox proportional hazards models and meta-analyses. The clusterin (CLU) locus was an independent genetic risk factor for MCI to AD progression (CLU rs9331888: hazard ratio (HR)=1.187 (1.054–1.32); P=0.0035). A polygenic score (PGS1) comprising nine established genome-wide AD risk loci predicted a small effect on the risk of MCI to AD progression in APOE-ɛ4 (apolipoprotein E-ɛ4) carriers (HR=1.746 (1.029–2.965); P=0.038). The novel AD loci reported by the International Genomics of Alzheimer's Project were not implicated in MCI to AD dementia progression. SNP-based polygenic risk scores comprising currently available AD genetic markers did not predict MCI to AD progression. We conclude that SNPs in CLU are potential markers for MCI to AD progression.

We have recently demonstrated that the antiproliferative activity of GnRH-II on human endometrial and ovarian cancer cell lines is not mediated through the GnRH-I receptor. A functional receptor for human GnRH-II has not yet been identified. In this study, we have generated a polyclonal antiserum to the putative human GnRH-II receptor using a peptide (YSPTMLTEVPPC) corresponding to the third extracellular domain coupled to keyhole limpet haemocyanin via the Cys residue. A database search showed no identical peptide sequences in any other human gene. To avoid cross-reactions against two similar amino acid sequences the antiserum was pre-absorbed using these peptides. Immune histological sections of human placenta and human endometrial, ovarian and prostate cancers using rabbit anti-human GnRH-II receptor antiserum showed GnRH-II receptor-like staining. Western blot analysis of cell membrane preparations of human endometrial and ovarian cancer cell lines yielded a band at approximately 43 kDa whereas Western blot analysis of cell membrane preparations of ovaries obtained from the marmoset monkey (Callithrix jacchus) yielded a band at approximately 54 kDa. To identify the GnRH-II receptor-like antigen we used the photo-affinity labelling technique. Photochemical reaction of I-125-labelled (4-azidobenzoyl)-N-hydroxysuccinimide-[D-LyS(6)]-GnRH-II (10(-9) M) with cell membrane preparations of human endometrial and ovarian cancer cells yielded a band at approximately 43kDa. In competition experiments, the GnRH-I agonist Triptorelin (10(-7) M) showed a weak decrease of I-125-labelled (4-azidobenzoyl)-N-hydroxysuccinimide-[D-LyS6]-GnRH-II binding to its binding site. The GnRH-I antagonist Cetrorelix (10(-7) M) showed a clearly stronger decrease, whereas GnRH-II agonist [D-Lys(6)]-GnRH-II (10(-7) M) was the most potent competitor. Western blot analysis of the same gel using rabbit anti-human GnRH-II receptor antiserum identified this band as GnRH-II receptor-like antigen.

Objectives: Urinary incontinence is a common symptom of urogenital aging that affects a considerable proportion of postmenopausal women. Morphological and morphometrical modulation of the bladder by estrogen are known. Yet data showing that this translates into changes of in vivo function of the urinary bladder are missing. Methods: We measured urodynamic parameters in anaesthetized, surviving rats. Following ovariectomy animals were divided into three groups and fed either an estradiol-, raloxifene-, or unsupplemented soy-free formula for ten weeks. Via a transurethral catheter the intravesical pressure was recorded during a stretch period (the urinary bladder was filled), and a one-minute isometric accommodation period immediately after the filling period. Upon termination of the experiment upper and lower halves of the bladder were processed histologically. Results: The estrogen-, and raloxifene-treated animals showed significantly higher pressures in responses to rapid stretch. Bladder compliance during the isometric period on the other hand was not significantly affected by these treatments. Thickness of the epithelial layer, collagen content and muscle bundles were significantly increased by estrogen and raloxifene treatment. Conclusions: This is a good animal model to investigate modulation of detrusor muscle contractility and stiffness. Both estradiol and raloxifene increase bladder contractility. Urinary bladder morphology indicates that estrogen acts primarily in the upper half of this organ since significant effects on collagen content and muscle fibers are only found in this part.

Thin films of La0.7Sr0.3MnO3 on MgO show a metal insulator transition and colossal magnetoresistance. The shape of this transition can be explained by intrinsic spatial inhomogeneities, which give rise to a domain structure of conducting and insulating domains at the submicrometer scale. These domains then undergo a percolation transition. The tunneling conductance and tunneling gap measured by scanning tunneling spectroscopy were used to distinguish and visualize these domains.

Objectives: Hormone replacement therapy (HRT) has therapeutic effects on climacteric complaints and prevents osteoporosis. Owing to the increased risks of breast cancer and cardiovascular diseases, patients look for alternatives. Cimicifuga racemosa (CR) preparations might be an alternative, because they proved to reduce climacteric complaints as efficiently as conjugated estrogens without exerting estrogenic effects in the uterus. Whether CR has positive effects on bone and in fat tissue is currently unknown. Therefore, osteoprotective effects of the CR extract BNO 1055 and an influence on fat tissue were studied in ovariectomized rats. Methods: Bone mineral density (BMD) of the tibia of ovariectomized (ovx) rats was determined by computer-assisted tomography (CT). CT scans of fat depots were perimetrically quantified. Bone turnover (osteocalcin, crosslaps) and lipocyte activity (leptin) were also determined. Uterine weights were measured and gene expression of estrogen-regulated uterine genes (IGF-1, ERbeta) was determined by RT-PCR. Results: Treatment of the ovx rats over a period of 3 months with E-2 and the CR extract BNO 1055 showed osteoprotective effects; both significantly reduced the loss of BMD in tibia. Serum osteocalcin levels were significantly reduced by both treatments, whereas only E-2, but not BNO 1055, reduced serum crosslaps. A paratibial fat depot and serum leptin concentration were also significantly reduced. In contrast to E-2, the CR extract showed no effect on uterine weight and gene expression of E-2-regulated genes. Conclusion: The CR extract BNO 1055 exerted estrogenic effects in the bone (particularly in osteoblasts) and in fat tissue, but not in the uterus of ovx rats. The extract appears to contain rat organ-specific selective estrogen receptor. modulators (SERMs), and if these findings can be approved in human it may be an alternative to HRT. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

Objectives: This review presents findings with clear statements from the literature as well as own results of effects of soy, red clover and their isoflavones as well as of the Cimicifuga racemosa extract BNO 1055. Experimental and clinical effects on climacteric complaints, osteoprotective effects, activity in the urogenital tract, and risks concerning cardiovascular diseases and mammary and endometrial tissue will be compared, also in comparison to classical hormone preparations. The question whether soy and red clover products and/or Cimicifuga racemosa (CR) preparations are endocrine disrupters or may fulfill the criteria of the so-called phyto-SERMs will be discussed. Methods: Review of selected publications since 1980 and summary of unpublished own results of the authors. Results: Experimental and clinical evidences suggest that soy/red clover and their isoflavones do not fulfill the criteria of an ideal SERM. They appear to have mild osteoprotective effects but do not improve climacteric complaints. Furthermore, they seem to stimulate uterine growth and mammary epithelial proliferation. In ovariectomized rats, the CR extract BNO 1055 showed many of the beneficial effects of 17beta-estradiol, including effects in the brain/hypothalamus to reduce serum LH levels, effects in the bone to prevent osteoporosis and estrogenic effects in the urinary bladder. The CR extract BNO 1055 had no uterotrophic effect. Conclusion: If clinical studies confirm these results, the Cimicifuga racemosa preparation BNO 1055 would appear as an ideal SERM and may therefore be an alternative to hormone replacement therapy. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

Political Strategy for Food Labelling Joint Statement of the Scientific Advisory Boards on Consumer and Food Policy and on Agricultural Policy at the Federal Minisity of Food. Agriculture and Consumer Protection September 2011 Consumers in modern consumer societies are confronted with an abundance of largely similar products, especially in the food sector. They are usually completely unable to process the detailed, product-related information these products contain. In this context labels are an important information tool for consumers. They can bundle information and are thus used more often and at an earlier point in time than other information. They can play a key role when it come to trust-related properties of products or services, as consumers do not have a reliable alternative source of this information. To contribute to consumers being able to make an informed decision, however, labels must be easy to understand, based on sound verified criteria and familiar to consumers. In addition to this, they must not be allowed to get lost in a flood of similar and sometimes ambiguous labels. With regard to the supplier side it is essential that labels provide a range of economic incentives to continually increase quality. So far these, challenges have not been sufficiently met by the agri-food industry and agri-food policy in Europe and Germany. From the point of view of the Scientific Advisory Boards, what is required is a long-term, consistent food labelling strategy that is preferably coordinated throughout the EU and that is based on an integrated view of environmental, food, consumer and agricultural policy and that integrates food labelling in all its complexity, including the context of other instruments. For important trust-related properties (health, environmental impact, social and animal welfare), which are becoming increasingly important for consumers, the Scientific Advisory Boards recommend an optional "umbrella" label showing the 4 above- mentioned labelling areas separately using a multi-level evaluation system. The umbrella label is intended to ensure easy recognition. The multi-level approach allows for differentiated evaluation and provides quality incentives for the suppliers. The focus (aggregation) on important labelling areas ensures a high amount of clarity, especially when terms are simultaneously protected by a ban on (misleading) associations. An overarching concept of this kind is only possible as a state-imposed or state-supported procedure. The Scientific Advisory Boards favour the latter but would like interest groups to be involved too. The animal welfare requirements for livestock offer especially good prerequisites for the testing of a multi-level label as described above. Binary characteristics, such as ingredients, origin, the use of genetic engineering or nanotechnology, are not suitable for an umbrella label concept. For such cases, the recommendation provides a decision grid for classifying the respective labelling area. For specific terms such as "GM-free" or "from mountain farms", the Scientific Advisory Boards recommend maintaining or introducing reserved terms that may only be used when legally defined conditions are met. At the same time, it should also be ensured in this area that terms are protected through a ban on (misleading) allusions. For private-sector labels, logos, references to testing or monitoring systems or specific advertising statements on the process quality, just as for state-imposed or state-supported labels, information should be made available at the point of sale or on the product packaging to enable the consumer to find further details on the system. It should be obligatory to state (e.g. on the internet) by whom the label is awarded and what the award criteria and the control process comprise. It is also necessary to ensure the independence of the inspectors and the control of the label providers (e.g. through accreditation), and to document this transparently. The observance or breach of legal minimum standards should generally not be communicated through a label.

Habitat fragmentation and reduction of population size have been found to negatively affect plant reproduction in 'new rare' species that were formerly common. This has been attributed primarily to effects of increased inbreeding but also to pollen limitation. In contrast, little is known about the reproduction of 'old rare' species that are naturally restricted to small and isolated habitats and thus may have developed strategies to cope with long-term isolation and small population size. Here we study the effects of pollen source and quantity on reproduction of the 'old rare' bumblebee-pollinated herb, Astragalus exscapus. In two populations of this species, we tested for pollen autodeposition, inbreeding depression and outbreeding depression. Caged plants were left unpollinated or were pollinated with pollen from the same plant, from the same population or from a distant population (50 km). Additionally, we tested for pollen limitation by pollen supplementation in four populations of different size and density. In the absence of pollinators, plants did not produce seed whereas self-pollinated plants did. This indicates a self-compatible breeding system dependent on insect pollination. Both self-pollination and, in one of the two populations, cross-pollination with pollen from plants from the distant population resulted in a lower number of seeds per flower than cross-pollination with pollen from plants from the resident population, indicating inbreeding and outbreeding depression. Pollen addition enhanced fruit set and number of seeds per flower in three of the four populations, indicating pollen limitation. The degree of pollen limitation was lowest in the smallest but densest population. Our results suggest that, similar to 'new rare' plant species, also 'old rare' species may be at risk of inbreeding depression and pollen limitation.

Silymarin is a widely used standardized mixture of flavonolignans and its major component Silybinin binds to cytosolic estrogen receptors. Here, we demonstrate that this binding is exclusive to the estrogen receptor beta (ERbeta). Treatment of ovariectomized (ovx) rats with silymarin or estradiol (E-2) may allow differentiation of biological effects mediated by the ERalpha or ERbeta. E-2 inhibited serum LH, cholesterol, LDL and HDL concentrations in the blood and increased gene expression of IGF1, HbEGF and C3 in the uterus, while silymarin was totally ineffective or antagonistic in altering these parameters. Both, E-2 and silymarin inhibited expression of uterine ERbeta gene. Hence, in the pituitary, liver (where the lipoproteins are synthesized) and uterus E-2 acts primarily via the ERalpha. Exclusive estrogenic effects of silymarin were observed in the metaphysis of the femur (W), on osteoblast parameters (gene expression of IGF1, TGFbeta1, osteoprotegerin, collagen-1alpha1, osteocalcin (OC)) and on the osteoclast activity marker tartrate resistant acid phosphatase (TRAP) gene expression of adult ovx rats. Our RT-PCR method detects ERbeta gene expression in all organs including developing bones but not in the ME of adult ovx rats. We conclude therefore, that the effects of silymarin in this part of the bone cannot be exerted via the ERalpha because it does not bind to this receptor subtype. Despite the failure to detect ERbeta mRNA in the MF of our animals the possibility exists that ERbeta protein is present and may mediate the effects of silymarin. Another possibility may be that the effect of silymarin and therefore possibly also of E-2 in the MF may be mediated via other possibly not yet identified receptors or via an ERbeta splice variant which is not detected by our PCR-method. (C) 2003 Elsevier Ltd. All rights reserved.

Grassland-based dairy production provides multiple benefits to farmers and to the wider society, but the European grassland area has been significantly reduced during the last decades. This paper aims to explore societal and economic options to support grassland-based dairy production in Europe. In the recent past, several societal initiatives have emerged to stimulate grassland-based dairy production: treaties, premiums and market concepts. When developing stimulating initiatives, the mindset of the farmer should be taken into account. Farmers are key actors when it comes to maintaining and improving grassland-based dairy production systems since they decide on the day-to-day management of the farm. To maintain grassland-based dairy production and to preserve the associated ecosystem services, it is, therefore, necessary to clearly show the importance of this production system for society to the farmers (show the customer perspective) and to support this by valuing the products from these systems accordingly. “New” business models should financially reward farmers for their added value contributions in delivering ecosystem services.

Background: Schizophrenia is a heterogeneous disorder. Over the years, different approaches have been proposed to approach this heterogeneity by categorizing symptom patterns. The study aimed to compare positive/negative and system-specific approaches to subtyping. Methods: We used the Positive and Negative Syndrome Scale (PANSS) and Bern Psychopathology Scale (BPS), which consists of subscales for three domains (language, affect and motor behavior) that are hypothesized to be related to specific brain circuits, to assess cross-sectional psychopathological characteristics in a sample of 100 inpatients with schizophrenia spectrum disorders. We then categorized participants into positive/negative and system-specific subgroups to allow comparisons of the two approaches. Results: The analyses revealed correlations between the PANSS positive subscore and the BPS affective subscore (r =.446, p <.001) and between the PANSS negative subscore and the BPS motor behavior subscore (r =.227, p =.023). As regards the positive and negative subtype, more participants were classified as positive in the language-dominant subtype (30.3%) and affect-dominant subtype (30.3%), whereas more were classified as negative in the motor behavior-dominant subtype (44.4%). However, most patients met the criteria for the mixed subtype. Conclusions: The results suggest that the positive/negative and system-specific approaches can be regarded as complementary. Future studies should examine both approaches in a longitudinal assessment of psychopathological symptoms and link them with qualitative-phenomenological approaches. (C) 2015 Elsevier Inc. All rights reserved.