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Jene Wissenschaften, deren Gegenstände vor allem der nichtmateriellen Welt zuzurechnen sind, haben hinsichtlich ihrer Öffentlichkeitsarbeit ein Problem: Sie produzieren in der Regel selbst keine Bilder, sollen aber ihre Forschung in eine zunehmend von bildhafter Kommunikation geprägte Öffentlichkeit hinein vermitteln. Stefan Klatt hat es im Rahmen seiner Tätigkeit für die Kolleg-Forschergruppe »Normenbegründung in Medizinethik und Biopolitik« und darüber hinaus mehr als hundertmal unternommen, dieses Dilemma durch zum Teil aufwendige Visualisierungen zu überwinden. Um den Jahreswechsel 2017/2018 zeigte die Ausstellung »Geistwürfe« im Münsteraner Schloss eine Zusammenschau der zwischen 2010 und 2017 entstandenen Motive und würdigte deren ganz eigene Sprache. The humanities, whose objects are predominantly attributable to the non-material world, have a problem with their public relations work: They usually do not produce images themselves, but are supposed to communicate their research to an increasingly pictorial public sphere. In the context of his work for the Centre for Advanced Study in Bioethics and beyond, Stefan Klatt has made efforts to overcome this dilemma more than a hundred times through at times complex visualisations. In late 2017 and early 2018, the exhibition "Geistwürfe" ("Spirit Casts") in Schloss Münster presented a synopsis of the motifs created between 2010 and 2017 and paid tribute to their very own language.

Quantifying and understanding the small-scale variability of nitrous oxide (N2O) and carbon dioxide (CO2) emission are essential for reporting accurate ecosystem greenhouse gas budgets. The objective of this study was to evaluate the spatial pattern of soil CO2 and N2O emissions and their relation to topography in a tropical montane forest. We measured fluxes of N2O and CO2 from 810 sampling locations across valley bottom, midslope, and ridgetop positions under controlled laboratory conditions. We further calculated the minimum number of samples necessary to provide best estimates of soil N2O and CO2 fluxes at the plot level. Topography exhibited a major influence on N2O emissions, with soils at midslope position emitting significantly less than at ridgetops and valley bottoms, but no consistent effect of topography on soil CO2 emissions was found. The high spatial variation of N2O and CO2 fluxes was further increased by changes in vegetation and soil properties resulting from human disturbance associated with charcoal production. Soil N2O and CO2 fluxes showed no spatial pattern at the plot level, with “hot spots” strongly contributing to the total emissions (10% of the soil cores represented 73 and 50% of the total N2O and CO2 emissions, respectively). Thus, a large number of samples are needed to obtain robust estimates of N2O and CO2 fluxes. Our results highlight the complex biogeochemical cycling in tropical montane forests, and the need to carefully address it in research experiments to robustly estimate soil CO2 and N2O fluxes at the ecosystem scale.

Impacts of soil and weather data aggregation in spatial modelling of net primary production of croplands. iCROPM 2016 International Crop Modelling Symposium "Crop Modelling for Agriculture and Food Security under Global Change"

Biological invasions can be associated with shifts of the species' climatic niches but the incidence of such shifts is under debate. The reproductive system might be a key factor controlling such shifts because it influences a species' evolutionary flexibility. However, the link between reproductive systems and niche dynamics in plant invasions has been little studied so far. We compiled global occurrence data sets of 13 congeneric sexual and apomictic species pairs, and used principal components analysis (PCA) and kernel smoothers to compare changes in climatic niche optima, breadths and unfilling/expansion between native and alien ranges. Niche change metrics were compared between sexual and apomictic species. All 26 species showed changes in niche optima and/or breadth and 14 species significantly expanded their climatic niches. However, we found no effect of the reproductive system on niche dynamics. Instead, species with narrower native niches showed higher rates of niche expansion in the alien ranges. Our results suggest that niche shifts are frequent in plant invasions but evolutionary potential may not be of major importance for such shifts. Niche dynamics rather appear to be driven by changes of the realized niche without adaptive change of the fundamental climatic niche. peerReviewed

Background: Visceral hypersensitivity is claimed to be involved in the pathogenesis of nonulcer dyspepsia (NUD). In a double-blind crossover study, we evaluated the effects of tropisetron, a 5-HT3 receptor antagonist, on gastric accommodation, reflex relaxation, and sensitivity in NUD patients. Methods: Eight patients and 10 healthy controls received placebo or 5 mg tropisetron on separate days. On each day, gastric accommodation and relaxation were investigated using a gastric barostat. The perception during gastric distension and relaxation was scored by a verbal perception score. Results: Under both medications, gastric accommodation and postprandial gastric reflex relaxation were not impaired in the NUD patients. The visceral perception was increased in the NUD patients and not substantially influenced by tropisetron. Conclusions: Tropisetron does not influence gastric accommodation, reflex relaxation, or gastric sensitivity in NUD patients and healthy controls.

The role of altered gastric motor functions for the development of obesity is still unclear. In this study, we investigated whether severe obesity is related to gastric dysfunctions or to abnormal perception in response to distension. 31 obese patients and 20 healthy volunteers were studied using an electronic barostat. Basal gastric tone, gastric accommodation, and perception in response to distension were not altered in obese patients. The median minimal distending pressure, reflecting the intra-abdominal pressure, was significantly elevated in obese patients, being 12 versus 7 mm Hg, respectively (p < 0.0001). We conclude that the proximal gastric motility, including perception and accommodation in response to intragastric distension, is not impaired in severe obesity. Whether disturbances of gastric reflex relaxation in response to a meal are involved in the pathogenesis of obesity remains to be established.

Visceral hypersensitivity is claimed to beinvolved in the pathogenesis of nonulcer dyspepsia(NUD). We evaluated whether gastric hypersensitivity isa consistent finding in an unselected group of NUDpatients. In 11 patients and 20 healthy controls, astandardized gastric distension was performed using agastric barostat. Perception was scored by aquestionnaire and compared between the two groups. Therewas a linear pressure/volume relationship duringgastric distension in both groups. The pain threshold inNUD patients was significantly lower compared tocontrols [5.5 ± 4.0 mm Hg above minimaldistending pressure (mdp) and 10.2 ± 2.2 mm Hg above mdp,respectively, P < 0.004], irrespective of the H.pylori status. However, more than 50% of the NUDperception scores were in the control range at mostdistension levels. Gastric hypersensitivity could be confirmed inNUD patients as a group. However, there is aconsiderable overlap concerning perception in responseto distension between unselected NUD patients andcontrols.

To test the diagnostic accuracy of faecal elastase (FE), a new test of exocrine pancreatic function, in a large prospective population of patients with abdominal complaints.Between January 1994 and December 1995, 131 patients (age range 17-82 years) were submitted for exocrine pancreatic function testing. Sixty-three patients had a firm diagnosis of chronic pancreatitis (CP) at stage I-III according to endoscopic retrograde cholangiopancreatography (ERCP). Twenty patients suffered from other pancreatic diseases (PD), and 48 patients had various other gastrointestinal diseases (GD). Fifty-seven healthy controls (HC) were also investigated. Stool specimens were analysed for FE by enzyme-linked immunosorbent assay (ELISA) and for faecal chymotrypsin (FC). The pancreolauryl serum test (PLT) was also performed in 97 patients and 23 healthy controls.FE was 200; 45-500 micrograms/g (median; range) in CP-I (n = 19), 94; 0-400 micrograms/g in CP-II (n = 14) and 38; 0-135 micrograms/g in CP-III patients (n = 30). With a cutoff of 200 micrograms/g, abnormal test results were found in 47% of CP-I, 79% of CP-II and 100% of CP-III patients; in 30% of PD patients, in 38% of GD patients and in 7% of HC. Sensitivity of abnormal FE in diagnosing CP was 79% (FC: 48%; PLT: 71%). The specificity of only 62% (FC: 73%; PLT: 67%) in the GD group increased to 78% (FC: 81%; PLT: 77%) when patients with small bowel diseases and diarrhoea (n = 22) were excluded.Faecal elastase is more sensitive than chymotrypsin and comparable to the pancreolauryl test in the diagnosis of chronic pancreatitis. Indirect exocrine pancreatic function tests are not helpful to differentiate between pancreatic and small bowel diseases in a prospective population of patients with abdominal complaints.

PURPOSE During a period of four years 104 mammograms were performed in 89 men. Mastectomies were carried out on 23 men (group 1). 66 patients (group 2) were followed up clinically and in 15 patients serial mammograms were obtained. MATERIAL AND METHOD In group 1 there were 5 patients with bilateral gynaecomastia, 9 with unilateral gynaecomastia and two with pseudogynaecomastia and there were 7 patients with malignancies. In group 2 there were 46 patients with bilateral gynaecomastia and 10 patients with unilateral gynaecomastia. Pseudogynaecomastia was found in 25 patients. There were 7 malignancies, of which 5 had been suspected clinically and one had been diagnosed as gynaecomastia by mammography. Two carcinomas in situ were missed clinically and also by mammography. CONCLUSION When malignancy is not suspected on clinical grounds the first examination should be sonography, mammography being reserved for cases of doubt. Where, however, malignancy is suspected, and for follow-up, mammography retains its primary position.

Background/Aims: A causative role of hepatitis C virus infection (HCV) has been discussed in the pathogenesis of mixed cryoglobulinaemia and in B-cell non-Hodgkin's lymphoma. No data are available concerning the newly discovered hepatitis G virus (HGV) and extrahepatic manifestations such as haematological malignancies. But, HCV and HGV most probably belong to the same family of Flavivirus. Consequently, we looked for the prevalence of HCV, HGV and cryoglobulins in patients with B-cell non-Hodgkin's lymphoma. Methods: Serum samples from 69 patients with non-Hodgkin's lymphoma were studied. Diagnosis of non-Hodgkin's lymphoma was established according to the Kiel classification. Active HCV- and HGV infections were investigated using polymerase chain reaction for detection of viral RNA. Cryoglobulins were detected from serum and monoclonal immunoglobulin components were analysed with immunofixation electrophoresis. In addition, we assessed the clinical course of HCV- and HGV-infected patients under chemotherapy. Results: Three of 69 (4.3%) patients with B-cell non-Hodgkin's lymphoma were HCV-infected and nine non-Hodgkin's lymphoma patients (13.0%) were positive for hepatitis G virus RNA. All HGV infected patients were suffering from low-grade non-Hodgkin's lymphoma. No HGV-infected patient was co-infected by HCV and neither HCV- nor HGV-infected patients showed clinical signs of chronic liver disease before, during or after chemotherapy. Serum samples from all patients were devoid of cryoglobulins. Conclusions: HCV seems to have no significance for the pathogenesis of non-Hodgkin's lymphoma in Germany. The increased prevalence of hepatitis G (16.3%) in patients with low-grade non-Hodgkin's lymphoma could suggest a pathological consequence of HGV infection outside of the liver. Evidence of clinically relevant hepatic disease in HGV infected patients was not obtained. Further, chemotherapy does not seem to affect the subsequent clinical course of HGV infection.

Background Secretory signal peptides (SPs) are well-known sequence motifs targeting proteins for translocation across the endoplasmic reticulum membrane. After passing through the secretory pathway, most proteins are secreted to the environment. Here, we describe the modification of an expression vector containing the SP from secreted acid phosphatase 1 (SAP1) of Leishmania mexicana for optimized protein expression-secretion in the eukaryotic parasite Leishmania tarentolae with regard to recombinant antibody fragments. For experimental design the online tool SignalP was used, which predicts the presence and location of SPs and their cleavage sites in polypeptides. To evaluate the signal peptide cleavage site as well as changes of expression, SPs were N-terminally linked to single-chain Fragment variables (scFv’s). The ability of L. tarentolae to express complex eukaryotic proteins with highly diverse post-translational modifications and its easy bacteria-like handling, makes the parasite a promising expression system for secretory proteins. Results We generated four vectors with different SP-sequence modifications based on in-silico analyses with SignalP in respect to cleavage probability and location, named pLTEX-2 to pLTEX-5. To evaluate their functionality, we cloned four individual scFv-fragments into the vectors and transfected all 16 constructs into L. tarentolae. Independently from the expressed scFv, pLTEX-5 derived constructs showed the highest expression rate, followed by pLTEX-4 and pLTEX-2, whereas only low amounts of protein could be obtained from pLTEX-3 clones, indicating dysfunction of the SP. Next, we analysed the SP cleavage sites by Edman degradation. For pLTEX-2, -4, and -5 derived scFv’s, the results corresponded to in-silico predictions, whereas pLTEX-3 derived scFv’s contained one additional amino-acid (AA). Conclusions The obtained results demonstrate the importance of SP-sequence optimization for efficient expression-secretion of scFv’s. We could successfully demonstrate that minor modifications in the AA-sequence in the c-region of the natural SP from SAP1, based on in-silico predictions following the (-3, -1) rule, resulted in different expression-secretion rates of the protein of interest. The yield of scFv production could be improved close to one order of magnitude. Therefore, SP-sequence optimization is a viable option to increase the overall yield of recombinant protein production.