Evasive lying in strategic communication

Information asymmetries in economic transactions are omnipresent and a regular source of fraudulent behavior. In a theoretical and an experimental analysis of a sender-receiver game we investigate whether sanctions for lying induce more truth-telling. The novel aspect in our model is that senders may not only choose between truth-telling and (explicit) lying, but may also engage in evasive lying by credibly pretending not to know. While we find that sanctions promote truth-telling when senders cannot engage in evasive lying, this is no longer true when evasive lying is possible. Then, explicit lying is largely substituted by evasive lying, which completely eliminates the otherwise positive effect of sanctions on the rate of truth-telling. As outlined in our model, the necessary prerequisite for such an 'erosion' effect is that evasive lying is perceived as sufficiently less psychologically costly than direct lying. Evidence from our experimental data and a survey conducted with additional participants indicate that the shift towards evasion can indeed be attributed to lower psychological costs. Overall, our results clearly demonstrate the limitations of sanctioning lying to counteract the exploitation of informational asymmetries and may explain the empirical evidence from the finance industry that sanctions for financial misconduct eventually appear to be not very effective

Evasive lying in strategic communication

Information asymmetries in economic transactions are omnipresent and a regular source of fraudulent behavior. In a theoretical and an experimental analysis of a sender-receiver game we investigate whether sanctions for lying induce more truth-telling. The novel aspect in our model is that senders may not only choose between truth-telling and (explicit) lying, but may also engage in evasive lying by credibly pretending not to know. While we find that sanctions promote truth-telling when senders cannot engage in evasive lying, this is no longer true when evasive lying is possible. Then, explicit lying is largely substituted by evasive lying, which completely eliminates the otherwise positive effect of sanctions on the rate of truth-telling. As outlined in our model, the necessary prerequisite for such an ‘erosion’ effect is that evasive lying is perceived as sufficiently less psychologically costly than direct lying. Evidence from our experimental data and a survey conducted with additional participants indicate that the shift towards evasion can indeed be attributed to lower psychological costs. Overall, our results clearly demonstrate the limitations of sanctioning lying to counteract the exploitation of informational asymmetries and may explain the empirical evidence from the finance industry that sanctions for financial misconduct eventually appear to be not very effective

Gibt es bei Körnererbsen Sortenunterschiede in der Anfälligkeit gegenüber bodenbürtigen Krankheiten?

Soil borne diseases cause damage in production of peas on many organic farms. Several varieties and breeding lines from Czech Republic and the United States were compared with German varieties in naturally infected soils. Because of very dry weather conditions a field trial with spring peas did not show diseases. In pot trials some varieties with colored flowers (containing tannine) and some winter peas were included in the trials. Some genotypes showed a tendency to a lower level of infection and to higher plant weights compared to plants grown in soil being treated with heat. But in most cases there were no statistic significances. Nevertheless there is a potential for plant breeding to develop peas varieties with a better tolerance against soil borne diseases. Differential diagnosis can be used for testing varieties

Utility of diagnostic tests in vomiting dogs presented to an internal medicine emergency service

IntroductionVomiting is a common sign in dogs presenting to emergency services. It can be self-limiting, a sign of a life-threatening extraintestinal, or intestinal disorder. Reasonable diagnostics should be performed to determine the underlying cause. This study aimed to assess the utility of diagnostic tests in vomiting dogs, and its correlation with patient history, and physical examination results. Additionally, parameters to differentiate uncomplicated vomiting from complicated vomiting were investigated.MethodsIn this prospective, observational, clinical study, data from 99 client-owned dogs with vomiting, presenting as first opinion cases, were evaluated. History, physical examination, duration of clinical signs, overall number of episodes of vomiting, appetite, and additional clinical signs were recorded. The standardized diagnostic evaluation of all patients included venous blood gas analysis, complete blood count, serum biochemistry profile, canine pancreatic lipase, abdominal radiographs, ultrasound, and urinalysis. Follow-up was performed 4–5 days later. Based on severity of disease and clinical course, dogs were categorized to “uncomplicated vomiting” (UN), or “complicated vomiting” (COM). The utility of each test for diagnosing the cause of vomiting was evaluated. Spearman correlation coefficient, Chi-squared-, unpaired t-, and Mann–Whitney U-test were used. Statistical significance was defined as p ≤ 0.05.ResultsOut of the 99 dogs, 34 had uncomplicated courses of disease (UN). In 60/99 cases, a diagnosis was obtained, and in 39/99 cases, the cause for vomiting remained unknown. Longer duration of clinical signs, and reduced appetite were associated with higher utility of abdominal ultrasound. A poor mentation was associated with a higher utility of blood examinations and abdominal radiographs. Dogs presenting with an impaired mentation or with additional clinical signs other than diarrhea, were more likely to be in the COM group.DiscussionBased on this investigation, general recommendations concerning the diagnostic approach for patients with vomiting could not be provided. For dogs who have exclusively vomiting as a clinical sign, and present in good mentation, further investigations might not be beneficial, and these dogs may recover with symptomatic treatment alone. Additional diagnostics could be indicated in dogs with additional clinical signs other than diarrhea

Analyse der Auswirkung lebensmittelrelevanter Substanzen auf die DNA-Methylierung mittels hochauflösender Schmelzkurvenanalyse

Die DNA-Methylierung ist ein wichtiger epigenetischer Faktor für die Kanzerogenese. Im Rahmen dieser Masterarbeit sollte der Methylierungsstatus in HT29 und MCF7 Zellen mittels methylierungssensitiver hochauflösender Schmelzkurvenanalyse (MS-HRM) analysiert werden. Es wurden dafür spezielle Primerpaare entworfen, die eine Amplifikation eines Bereichs der Promotorregion von Tumorsuppressorgenen ermöglichen. Dafür wurden die Gene CDKN2A (Cyclin-dependent kinase inhibitor 2A), HIC1 (Hypermethylated in cancer 1) und RASSF1 (Ras association domain-containing protein 1) ausgewählt. Nur für CDKN2A konnten geeignete Primer gefunden und die MS-HRM Methode optimiert werden. Die MS-HRM Methode sollte im Rahmen dieser Arbeit validiert werden, wozu die quantitative MethyLight Methode ausgewählt wurde. Diese wurde kommerziell erworben und in einem ersten Schritt mittels Kontroll-Standards überprüft. Die Amplifikation der Real-Time PCR zeigte eine schlechte Effizienz und daraus ergaben sich stark abweichende Werte vom tatsächlichen Methylierungsgrad. Die Genauigkeit der Methode war damit unzureichend für eine Überprüfung der mit der MS-HRM Analyse erhaltenen Ergebnisse. Trotzdem wurden einige Proben aus Inkubationsversuchen mit Zellen analysiert und mit den Werten aus der MS-HRM verglichen. Während bei einem niedrigen Methylierungsgrad höhere Ergebnisse mit der MS-HRM Methode erzielt wurden, war es bei einem höheren Methylierungsgrad umgekehrt. Der Methylierungsgrad der Poromotorregionen der einzelnen Gene wurde in vitro in HT29 und MCF7 Zellen untersucht. Es wurden zusätzlich Inkubationsversuche mit verschiedensten lebensmittelrelevanten Substanzen durchgeführt, um eine etwaige Veränderung des DNA-Methylierungsgrads durch diese Stoffe zu untersuchen. Zusätzlich wurde die DNA aus Zellen von früher in der Arbeitsgruppe durchgeführten Inkubationsversuchen analysiert. Bei den Substanzen handelte es sich um Lebensmittel-Inhaltsstoffe wie Lignane ((+)-Lariciresinol und (-)-Matairesinol), Isoflavone (Genistein und Daidzein), Flavonole (Quercetin) oder bei der Zubereitung von Fleischwaren entstehende heterocyclische aromatische Amine (MeIQx und PhIP). Zusätzlich wurde die Wirkung von Kontaminanten wie Bisphenol A (BPA) und Mykotoxinen (Desoxynivalenol und Zearalenon) untersucht. Es wurde außerdem der demethylierende Arzneistoff 5-Aza-2‘-Deoxycytidin (5-Aza-dC) als Positivkontrolle verwendet. Für jede Substanz wurde die Wirkung konzentrationsabhängig bestimmt. Untersucht wurde der Promotor einer Reihe von Genen, die Methoden dazu wurden von B. Druml und E. Habla entwickelt, abgesehen von jener für CDKN2A. Bei den zusätzlichen Tumorsuppressorgenen handelte es sich um APC, DAPK1, GATA-4, NTRK2 und OSMR. Die Promotorregionen von APC und DAPK1 waren in HT29 Zellen nicht methyliert, jene von OSMR lag in MCF7 Zellen unmethyliert vor. Da von den verwendeten Substanzen keine methylierende Wirkung erwartet wurde, wurde der Einfluss auf nicht methylierte Promotorregionen von Genen nicht untersucht. Für die Versuche mit der HT29 Zelllinie konnten keine Effekte beobachtet werden. Einzig 5-Aza-dC zeigte die erwartete Wirkung, mit einem konzentrationsabhängigen Effekt, der bei 1 µM am stärksten war und mit zunehmender Konzentration abnahm. Die MCF7 Zellen wurden mit Genistein, Quercetin, Daidzein, BPA und 5-Aza-dC inkubiert. Allerdings wurden zum Screening nur wenige Versuche durchgeführt. Unter den verwendeten Substanzen waren auch einige endokrin wirksame, von denen eine Wirkung auf die MCF7 Zellen erwartet wurde. Tatsächlich konnte nur eine Inhibition des Wachstums durch Genistein, Quercetin und BPA beobachtet werden, eine Veränderung des Methylierungsstatus des Promotors kann für CDKN2A als Folge der Behandlung mit Genistein vermutet werden. Zusätzlich wurde auch hier bei der Inkubation mit 5-Aza-dC der stärkste demethylierende Effekt bei einer Konzentration von 1 µM erhalten. Aus Zeitgründen wurden einige dieser Inkubationsversuche nur einmal durchgeführt. Für eine endgültige Aussage über eine signifikante Wirkung müssten noch weitere Inkubations-versuche gemacht werden. Die Zellen wurden jeweils für 96 Stunden mit der jeweiligen Substanz inkubiert, was für manche bioaktive Stoffe zu kurz sein könnte. Daher wäre es außerdem sinnvoll, einen etwaigen Einfluss bei längeren Inkubationsdauern zu untersuchen.DNA-methylation is known to play an important factor in carcinogenesis, particularly through silencing of tumor suppressor genes. The aim of the present master thesis was to develop methylation-sensitive high-resolution melting (MS-HRM) methods allowing the determination of the methylation status in the promoter region of different tumor suppressor genes. The methods should then be applied to determine the methylation status in HT29 and MCF7 cells and to investigate any demethylating effects of food relevant substances. At the beginning primer pairs for the tumor suppressor genes CDKN2A, HIC1 and RASSF1 were designed. However, only for CDNK2A an appropriate primer pair was found and subsequently the MS-HRM method was optimized. A commercially available MethyLight method should be used to validate the MS-HRM method for CDNK2A. However, by analyzing DNA standards of known methylation status we observed that the commercial kit did not perform well and suffered from low amplification efficiency, in particular of unmethylated DNA. Due to this PCR bias, the methylation extent determined with the MethyLight kit differed significantly from the actual methylation status of the DNA standards. The MethyLight method was therefore not applicable to verify the accuracy of the MS-HRM method developed in the present master thesis. In addition to the MS-HRM method for CDNK2A, further MS-HRM methods (developed by former diploma students) were applied to investigate the methylation status of tumor suppressor genes (NTRK2, OSMR and GATA-4) in HT29 cells. Incubation experiments with different food related substances were carried out to investigate a potential effect on the DNA-methylation level. The substances (genistein, quercetin and the demethylating drug 5-aza-2’-deoxycytidine (5-Aza-dC)) were incubated in a concentration range from 1 to 100 µM for 96 hours. In addition, incubation experiments with (+)-lariciresinol, (-)-matairesinol, daidzein, MeIQx, PhIP, desoxynivalenol, zearalenone and bisphenol A (BPA) were carried out by former diploma students. In untreated HT29 cells the promoter regions of CDKN2A, NTRK2, OSMR and GATA-4 were found to be highly methylated. 5-Aza-dC showed a demethylating effect on the promoter regions of all genes. The strongest effect was observed at 1 µM. None of the other test substances was found to show a demethylation effect. In screening experiments, the effect of genistein, quercetin, 5-Aza-dC, daidzein and BPA on the promoter region of CDKN2A, NTRK2, APC and DAPK1 in MCF7 cells was investigated. Again, 5-Aza-dC was found to show a demethylating effect. Incubation with genistein, quercetin and BPA resulted in inhibiting cell growth. However, an influence on the DNA methylation level was not observed

Studien zu den Totalsynthesen von Schiglauton A und Antalam A

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Large-Scale Production of Bioactive Ingredients as Supplements for Healthy Human and Animal Nutrition

In this review, synthetic strategies and the development of environmentally benign methods for the production of economically important vitamins, carotenoids, and nutraceuticals used as food and feed supplements are illustrated by selected examples. The application of efficient catalytic transformations in multi-step chemical syntheses of such natural products enables technically feasible and cost-effective processes. For the preparation of fat-soluble (isoprenoid) vitamins A and E and the water-soluble vitamin (+)-biotin, homogeneous metal catalysis, including enantioselective transformations, heterogeneous and enzymatic catalysis serve as key methodologies. In the area of carotenoids, general building concepts and coupling methods for the total synthesis of ?-carotene and astaxanthin are discussed. Biotechnological methods and isolation from natural sources are also employed successfully, as exemplified for the xanthophyll lutein and the antioxidant (–)-epigallocatechin gallate. Lastly, key steps of the chemical synthesis of the polyphenol resveratrol are highlighted

MicroRNA expression differs in cutaneous squamous cell carcinomas and healthy skin of immunocompetent individuals

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers, but the influence of microRNA (miRNA) expression has only been sporadically analysed. We hypothesized that miRNAs are differentially expressed in cSCC and hence influence its development. We therefore isolated total miRNA from well-differentiated cSCCs and from controls without SCC. Expression analyses of 12 miRNAs showed three significantly differentially expressed miRNAs. We identified a significant upregulation of the miR-21 and the miR-31, a proto-oncogene like miR-21. While the upregulated expression of miR-21 has been known for some time, the increased expression of miR-31 was never shown so clearly. Furthermore, we showed the upregulation of miRNA-205, which has never been described before. The miR-205 induces specific keratinocyte migration and could be a characteristic marker for cSCC. It has to be determined in following studies whether these upregulated expressions are specific for cSCC and if so, for which cSCC stages