TY - JOUR A1 - Leidinger, Ludwig A1 - Vedder, Daniel A1 - Cabral, Juliano Sarmento T1 - Temporal environmental variation may impose differential selection on both genomic and ecological traits JF - Oikos N2 - The response of populations and species to changing conditions determines how community composition will change functionally, including via trait shifts. Selection from standing variation has been suggested to be more efficient than acquiring new mutations. Yet, studies on community trait composition and trait selection largely focus on phenotypic variation in ecological traits, whereas the underlying genomic traits remain understudied. Using a genome‐explicit, niche‐ and individual‐based model, we address the potential interactions between genomic and ecological traits shaping communities under an environmental selective forcing, namely temporal positively autocorrelated environmental fluctuation. In this model, all ecological traits are explicitly coded by the genome. For our experiments, we initialized 90 replicate communities, each with ca 350 initial species, characterized by random genomic and ecological trait combinations, on a 2D spatially explicit landscape with two orthogonal gradients (temperature and resource use). We exposed each community to two contrasting scenarios: without (i.e. static environments) and with temporal variation. We then analyzed emerging compositions of both genomic and ecological traits at the community, population and genomic levels. Communities in variable environments were species poorer than in static environments, and populations more abundant, whereas genomes had lower genetic linkage, mean genetic variation and a non‐significant tendency towards higher numbers of genes. The surviving genomes (i.e. those selected by variable environments) coded for enhanced environmental tolerance and smaller biomass, which resulted in faster life cycles and thus also in increased potential for evolutionary rescue. Under temporal environmental variation, larger, less linked genomes retained more variation in mean dispersal ability at the population level than at genomic level, whereas the opposite trend emerged for biomass. Our results provide clues to how sexually‐reproducing diploid plant communities might react to variable environments and highlights the importance of genomic traits and their interaction with ecological traits for eco‐evolutionary responses to changing climates. KW - environmental variability KW - genomic traits KW - mechanistic model KW - rapid evolution KW - standing variation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-238945 VL - 130 IS - 7 SP - 1100 EP - 1115 ER - TY - JOUR A1 - Lehenberger, Maximilian A1 - Foh, Nina A1 - Göttlein, Axel A1 - Six, Diana A1 - Biedermann, Peter H. W. T1 - Nutrient-Poor Breeding Substrates of Ambrosia Beetles Are Enriched With Biologically Important Elements JF - Frontiers in Microbiology N2 - Fungus-farming within galleries in the xylem of trees has evolved independently in at least twelve lineages of weevils (Curculionidae: Scolytinae, Platypodinae) and one lineage of ship-timber beetles (Lymexylidae). Jointly these are termed ambrosia beetles because they actively cultivate nutritional “ambrosia fungi” as their main source of food. The beetles are obligately dependent on their ambrosia fungi as they provide them a broad range of essential nutrients ensuring their survival in an extremely nutrient-poor environment. While xylem is rich in carbon (C) and hydrogen (H), various elements essential for fungal and beetle growth, such as nitrogen (N), phosphorus (P), sulfur (S), potassium (K), calcium (Ca), magnesium (Mg), and manganese (Mn) are extremely low in concentration. Currently it remains untested how both ambrosia beetles and their fungi meet their nutritional requirements in this habitat. Here, we aimed to determine for the first time if galleries of ambrosia beetles are generally enriched with elements that are rare in uncolonized xylem tissue and whether these nutrients are translocated to the galleries from the xylem by the fungal associates. To do so, we examined natural galleries of three ambrosia beetle species from three independently evolved farming lineages, Xyleborinus saxesenii (Scolytinae: Xyleborini), Trypodendron lineatum (Scolytinae: Xyloterini) and Elateroides dermestoides (Lymexylidae), that cultivate unrelated ambrosia fungi in the ascomycete orders Ophiostomatales, Microascales, and Saccharomycetales, respectively. Several elements, in particular Ca, N, P, K, Mg, Mn, and S, were present in high concentrations within the beetles’ galleries but available in only very low concentrations in the surrounding xylem. The concentration of elements was generally highest with X. saxesenii, followed by T. lineatum and E. dermestoides, which positively correlates with the degree of sociality and productivity of brood per gallery. We propose that the ambrosia fungal mutualists are translocating essential elements through their hyphae from the xylem to fruiting structures they form on gallery walls. Moreover, the extremely strong enrichment observed suggests recycling of these elements from the feces of the insects, where bacteria and yeasts might play a role. KW - ambrosia beetle KW - ecological stoichiometry KW - microbiome KW - nutrients KW - macro- and micro-elements KW - element translocation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-237602 SN - 1664-302X VL - 12 ER - TY - JOUR A1 - Lehenberger, Maximilian A1 - Benkert, Markus A1 - Biedermann, Peter H. W. T1 - Ethanol-Enriched Substrate Facilitates Ambrosia Beetle Fungi, but Inhibits Their Pathogens and Fungal Symbionts of Bark Beetles JF - Frontiers in Microbiology N2 - Bark beetles (sensu lato) colonize woody tissues like phloem or xylem and are associated with a broad range of micro-organisms. Specific fungi in the ascomycete orders Hypocreales, Microascales and Ophistomatales as well as the basidiomycete Russulales have been found to be of high importance for successful tree colonization and reproduction in many species. While fungal mutualisms are facultative for most phloem-colonizing bark beetles (sensu stricto), xylem-colonizing ambrosia beetles are long known to obligatorily depend on mutualistic fungi for nutrition of adults and larvae. Recently, a defensive role of fungal mutualists for their ambrosia beetle hosts was revealed: Few tested mutualists outcompeted other beetle-antagonistic fungi by their ability to produce, detoxify and metabolize ethanol, which is naturally occurring in stressed and/or dying trees that many ambrosia beetle species preferentially colonize. Here, we aim to test (i) how widespread beneficial effects of ethanol are among the independently evolved lineages of ambrosia beetle fungal mutualists and (ii) whether it is also present in common fungal symbionts of two bark beetle species (Ips typographus, Dendroctonus ponderosae) and some general fungal antagonists of bark and ambrosia beetle species. The majority of mutualistic ambrosia beetle fungi tested benefited (or at least were not harmed) by the presence of ethanol in terms of growth parameters (e.g., biomass), whereas fungal antagonists were inhibited. This confirms the competitive advantage of nutritional mutualists in the beetle’s preferred, ethanol-containing host material. Even though most bark beetle fungi are found in the same phylogenetic lineages and ancestral to the ambrosia beetle (sensu stricto) fungi, most of them were highly negatively affected by ethanol and only a nutritional mutualist of Dendroctonus ponderosae benefited, however. This suggests that ethanol tolerance is a derived trait in nutritional fungal mutualists, particularly in ambrosia beetles that show cooperative farming of their fungi. KW - ambrosia fungi KW - bark and ambrosia beetles KW - symbiont selection KW - ethanol KW - detoxification KW - Ips typographus Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222222 SN - 1664-302X VL - 11 ER - TY - JOUR A1 - Latifi, Hooman A1 - Holzwarth, Stefanie A1 - Skidmore, Andrew A1 - Brůna, Josef A1 - Červenka, Jaroslav A1 - Darvishzadeh, Roshanak A1 - Hais, Martin A1 - Heiden, Uta A1 - Homolová, Lucie A1 - Krzystek, Peter A1 - Schneider, Thomas A1 - Starý, Martin A1 - Wang, Tiejun A1 - Müller, Jörg A1 - Heurich, Marco T1 - A laboratory for conceiving Essential Biodiversity Variables (EBVs)—The ‘Data pool initiative for the Bohemian Forest Ecosystem’ JF - Methods in Ecology and Evolution N2 - Effects of climate change‐induced events on forest ecosystem dynamics of composition, function and structure call for increased long‐term, interdisciplinary and integrated research on biodiversity indicators, in particular within strictly protected areas with extensive non‐intervention zones. The long‐established concept of forest supersites generally relies on long‐term funds from national agencies and goes beyond the logistic and financial capabilities of state‐ or region‐wide protected area administrations, universities and research institutes. We introduce the concept of data pools as a smaller‐scale, user‐driven and reasonable alternative to co‐develop remote sensing and forest ecosystem science to validated products, biodiversity indicators and management plans. We demonstrate this concept with the Bohemian Forest Ecosystem Data Pool, which has been established as an interdisciplinary, international data pool within the strictly protected Bavarian Forest and Šumava National Parks and currently comprises 10 active partners. We demonstrate how the structure and impact of the data pool differs from comparable cases. We assessed the international influence and visibility of the data pool with the help of a systematic literature search and a brief analysis of the results. Results primarily suggest an increase in the impact and visibility of published material during the life span of the data pool, with highest visibilities achieved by research conducted on leaf traits, vegetation phenology and 3D‐based forest inventory. We conclude that the data pool results in an efficient contribution to the concept of global biodiversity observatory by evolving towards a training platform, functioning as a pool of data and algorithms, directly communicating with management for implementation and providing test fields for feasibility studies on earth observation missions. KW - bohemian forest ecosystem KW - data pool KW - forest ecosystem science KW - remote sensing KW - remote sensing‐enabled essential biodiversity variables Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262743 VL - 12 IS - 11 ER - TY - JOUR A1 - Lasway, Julius V. A1 - Kinabo, Neema R. A1 - Mremi, Rudolf F. A1 - Martin, Emanuel H. A1 - Nyakunga, Oliver C. A1 - Sanya, John J. A1 - Rwegasira, Gration M. A1 - Lesio, Nicephor A1 - Gideon, Hulda A1 - Pauly, Alain A1 - Eardley, Connal A1 - Peters, Marcell K. A1 - Peterson, Andrew T. A1 - Steffan-Dewenter, Ingolf A1 - Njovu, Henry K. T1 - A synopsis of the Bee occurrence data of northern Tanzania JF - Biodiversity Data Journal N2 - Background Bees (Hymenoptera: Apoidea: Anthophila) are the most important group of pollinators with about 20,507 known species worldwide. Despite the critical role of bees in providing pollination services, studies aiming at understanding which species are present across disturbance gradients are scarce. Limited taxononomic information for the existing and unidentified bee species in Tanzania make their conservation haphazard. Here, we present a dataset of bee species records obtained from a survey in nothern Tanzania i.e. Kilimanjaro, Arusha and Manyara regions. Our findings serve as baseline data necessary for understanding the diversity and distribution of bees in the northern parts of the country, which is a critical step in devising robust conservation and monitoring strategies for their populations. New information In this paper, we present information on 45 bee species belonging to 20 genera and four families sampled using a combination of sweep-netting and pan trap methods. Most species (27, ~ 60%) belong to the family Halictidae followed by 16 species (35.5%) from the family Apidae. Megachilidae and Andrenidae were the least represented, each with only one species (2.2%). Additional species of Apidae and Megachilidae sampled during this survey are not yet published on Global Biodiversity Information Facility (GBIF), once they will be available on GBIF, they will be published in a subsequent paper. From a total of 953 occurrences, highest numbers were recorded in Kilimanjaro Region (n = 511), followed by Arusha (n = 410) and Manyara (n = 32), but this pattern reflects the sampling efforts of the research project rather than real bias in the distributions of bee species in northern Tanzania. KW - agriculture KW - bee pollinator KW - distribution KW - disturbance gradient KW - grazing KW - species diversity KW - Tanzania Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-265018 VL - 9 ER - TY - THES A1 - Lapuente, Juan M. T1 - The Chimpanzees of the Comoé National Park, Ivory Coast. Status, distribution, ecology and behavior T1 - Die Schimpansen im Comoé Nationalpark, Elfenbeinküste. Status, Verbreitung, Ökologie und Verhalten N2 - Although wild chimpanzees (Pan troglodytes) have been studied intensely for more than 50 years, there are still many aspects of their ecology and behavior that are not well understood. Every time that a new population of chimpanzees has been studied, new behaviors and unknown aspects of their ecology have been discovered. All this accumulated knowledge is helping us to piece together a model of how could last human and chimpanzee common ancestors have lived and behaved between seven and five million years ago. Comoé chimpanzees had never been studied in depth, until we started our research in October 2014, only a few censuses had been realized. The last surveys prior our work, stated that the population was so decimated that was probably functionally extinct. When we started this research, we had to begin with a new intensive survey, using new methods, to ascertain the real status and distribution of the chimpanzees living in Comoé National Park (CNP). During the last five years, we have realized a deep study aiming to know more about their ecology and behavior. We combined transects and reconnaissance marches (recces) with the use of camera traps, for the first time in CNP, obtaining a wealth of data that is not fully comprised in this dissertation. With this research, we determined that there is a sustainable continuous population of Western chimpanzees (Pan troglodytes verus) in CNP and the adjacent area of Mont Tingui, to the West, with a minimum of 127 weaned chimpanzees living in our main 900 km2 study area, SW of CNP. We found that this population is formed by a minimum of eight different chimpanzee communities, of which we studied seven, four of them more in detail. These chimpanzees spent much more time in the forest than in the savanna habitats. We also found that Comoé chimpanzees consumed at least 58 different food items in their dit, which they obtained both from forest and savanna habitats. Another finding was that insectivory had an important role in their diet, with at least four species of ants, three of termites and some beetle larvae. These chimpanzees also hunted at least three species of monkeys and maybe rodents and duikers and occasionally consumed the big land snails of genus Achatina. We found that, during the fruit scarcity period in the late rainy season, they intensely consumed the cambium of Ceiba pentandra, as fallback food, much more than the bark or cambium of any other tree species. Another interesting finding was that all the chimpanzees in the studied area realized this particular bark-peeling behavior and had been repeatedly peeling the trees of this species for years. This did not increase tree mortality and the damage caused to the trees was healed in two years, not reducing the growth, thus being a sustainable use of the trees. We found that Comoé chimpanzees produced and used a great variety of tools, mainly from wooden materials, but also from stone and herbaceous vegetation. Their tool repertory included stick tools to dip for Dorylus burmeisteri ants, to fish for Camponotus and Crematogaster ants, to dip for honey, mainly from Meliponini stingless bees, but sometimes from honey bees (Apis mellifera). It also included the use of stick tools to fish termites of Macrotermes subhyalinus and Odontotermes majus (TFTs), to dip for water from tree holes and investigatory probes for multiple purposes. Additionally, these chimpanzees used leaf-sponges to drink from tree holes and to collect clayish water from salt-licks. They also used stones to hit the buttresses of trees during displays, the so called accumulative stone throwing behavior and probably used stones as hammers, to crack open hard-shelled Strichnos spinosa and Afraegle paniculata fruits and Achatina snails. The chimpanzees also used objects that are not generally accepted as animal tools, for being attached to the substrate, with different purposes: they drummed buttresses of trees with hands and/or feet to produce sound during male displays and they pounded open hard-shelled fruits, Achatina snails and Cubitermes termite mounds on stone or root anvils. We finally measured the stick tools and found significant differences between them suggesting that they were specialized tools made specifically for every purpose. We studied more in detail the differences between apparently similar tools, the honey dipping tools and the water dipping tools, often with brushes made at their tips to collect the fluids. These last tools were exclusive from Comoé and have not been described at any other site. We found that total length, diameter and brush length were significantly different, suggesting that they were specialized tools. We concluded that Comoé chimpanzees had a particular culture, different from those of other populations of Western chimpanzees across Africa. Efficient protection, further research and permanent presence of research teams are required to avoid that this unique population and its culture disappears by the poaching pressure and maybe by the collateral effects of climate change. N2 - Obwohl wild lebende Schimpansen (Pan troglodytes) seit mehr als 50 Jahren intensiv untersucht werden, gibt es noch zahlreiche Aspekte ihrer Ökologie und ihres Verhaltens, die nicht gut verstanden werden. Jedes Mal, wenn eine neue Population von Schimpansen studiert wurde, wurden neue Verhaltensweisen und unbekannte Aspekte ihrer Ökologie entdeckt. All dieses gesammelte Wissen hilft uns, ein Modell zu erstellen, wie lange die gemeinsamen Vorfahren von Menschen und Schimpansen vor sieben bis fünf Millionen Jahren gelebt und sich verhalten haben könnten. Als wir im Oktober 2014 mit unserer Forschung begannen waren die Comoé-Schimpansen, bis auf einige Populations-Zensus von Schimpansen in der Elfenbeinküste, noch nie eingehend untersucht worden. Die letzte Zählung bevor unsere Arbeit began ergab, dass die Schimansenpopulation so stark dezimiert war, dass sie als funktionell ausgestorben erarchtet werden konnte. Zum Beginn unserer Forschung, führten wir zuerst mit neusten Methoden einen neuen detailierten Zensus durch, um den tatsächlichen Status und die Verteilung der im Comoé-Nationalpark (CNP) lebenden Schimpansen zu ermitteln. In den folgenden fünf Jahren haben wir zudem eine umfassende Studie durchgeführt, um mehr über ihre Ökologie und ihr Verhalten zu erfahren. Wir haben im CNP erstmals systematische Transekte und Datenerhebungen mittels Kamerafallen kombiniert, um eine Fülle von Erkenntnissen zu erhalten, die in dieser Dissertation nicht vollständig enthalten sind. Wir stellten fest, dass es in CNP und dem westlich angrenzenden Gebiet des Mont Tingui nach wie vor eine nachhaltige und kontinuierliche Population westlicher Schimpansen (Pan troglodytes verus) existiert, wobei mindestens 131 adulte (entwöhnte) Schimpansen in unserem 900 km² großen Hauptuntersuchungsgebiet südwestlich des CNP leben. Diese Population besteht aus mindestens acht verschiedenen Schimpansengruppen, von denen wir sieben untersuchten, vier davon genauer. Wir konnten zeigen dass diese Schimpansen deutlich mehr Zeit im Wald als in den angrenzenden Savannenhabitaten verbringen. Wir stellten fest, dass Comoé- Schimpansen mindestens 58 verschiedene Futtermittel aus Wald- als auch aus Savannenhabitaten nutzen. Zudem spielt der Konsum von Insekten, bestelhend aus mindestens vier Ameisen-, drei Termiten- und verschiedenene Käferlarven eine wichtige Rolle in ihrem Ernährungsreportoire. Die Comoé-Schimpansen jagen zudem mindestens drei Affena sowie möglicherweise Nagetiere und Duiker, und fraßen gelegentlich die großen Schnecken der Gattung Achatina. Wir fanden heraus, dass sie den typischen Mangel an reifen Fuechten in der \späten Regenzeit durch den intensiven Konsum der Rinde (Kambium) von Ceiba pentandra kompensieren. Alle Schimpansen im untersuchten Gebiet zeigten dieses besondere Verhalten, bei dem sie die Rinde von Ceiba Bäumen schälen. Wir konnte zeigen, dass die Schimpansen diese Bäume seit Jahren wiederholt geschält hatten, was offenbar den Bäumen keinen nachhaltigen Schaden zugefügte. Innerhalb von zwei Jahren ware die Schäden geheilt and das Wachstum nicht verringert, was schlussfolgern lässt dass die Nutzung der Baumrinde nachhaltig ist. Wir fanden heraus, dass Comoé-Schimpansen eine Vielzahl von Werkzeugen aus Vegetation aber auch Steinen herstellten und verwendeten. Das Werkzeugrepertoire umfasste Stöckchen zur Gewinning von on Ameisen der Art Dorylus burmeisteri, sowie Ameisen der Gattungen Camponotus und Crematogaster, aber auch von Bienenhonig produziert von der stachellosen Gattung Melipoa sowie von Apis mellifera. Die Schimpansen nutzen ausserdem Pflanzenwerkzeuge zum Termitenfischen von Macrotermes subhyalinus und Odontotermes majus, um an das Wasser in Baumvertiefungen zu gelangen, sowie für diverse andere Untersuchungszwecke. Zusätzlich verwenden die Comoé-Schimpansen Blattschwämme, um aus Baumlöchern zu trinken und lehmiges Wasser von den Salzlecken zu sammeln. Im Rahmen ihres Imponierverhaltens schleuden sie Steine an die Brettwurzeln spezieller grosser Bäume, ein neu entdecktes Verhalten das als akkumulatives Steinerfen bezeichnet wird. Es ist wahrscheinlich dass sie Steine auch als Hammerwerkzeuge nutzen, um hartschalige Früchte wie Strichnos spinosa und Afraegle paniculata sowie grosse Landschnecken aufzubrechen. Die Schimpansen verwenden Gegenstände auch in anderen Zusammenhängen, die nicht unbedingt als Werkzeuggebrauch definiert werden können: Sie trommlen im Rahmen vom männlichen Imponierverhalten laut mit Händen und Füßen auf die Brettwurzeln von Bäumen, und zerschmettern harte Früchte, Schneckenhäuser und Cubitermes-Termitenhügel auf Ambossen aus Gestein oder Wurzeln. Wir haben signifikante Unterschiede beim Vermessen der Stabwerkzeuge festgestellt, was darauf hindeutet, dass es sich um Spezialwerkzeuge handelt, die speziell für verschiedene Zwecke hergestellt werden. Wir haben insbesondere die Unterschiede zwischen scheinbar ähnlichen Pinselwerkzeugen für den Konsum von Flüssigkeiten (H zu verhindern, sowie die möglichen Nebeneffekte des Klimawandels zu dokumentieren.onig, Wasser) genauer untersucht. Diese Pinselwerkzeuge der Comoé-Schimpansen sind offenbar einzigartig und bislang nicht in der Literatur beschrieben. Gesamtlänge, Durchmesser und Bürstenlänge weichen je nach Verwendungszweck der Pinsel erheblich voneinander ab, was darauf hindeutet, dass es sich um Spezialwerkzeuge handelt. Wir schlussfolgern, dass die Kultur der Comoé-Schimpansen einzigartig innerhalb der der westlichen Schimpansen ist. Um diese einzigartige Population von Schimpansen effektiv zu schützen benötigt es weitere Forschung sowie die ständige Präsenz von Forschungsteams, um Wilderei KW - Chimpanzee KW - ecology KW - distribution KW - behavior KW - Comoé National Park KW - tool-use KW - primate KW - tool KW - diet KW - habitat KW - Parc National de la Comoé KW - Schimpanse KW - Verhalten Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-223180 ER - TY - JOUR A1 - Kühnemundt, Johanna A1 - Leifeld, Heidi A1 - Scherg, Florian A1 - Schmitt, Matthias A1 - Nelke, Lena C. A1 - Schmitt, Tina A1 - Bauer, Florentin A1 - Göttlich, Claudia A1 - Fuchs, Maximilian A1 - Kunz, Meik A1 - Peindl, Matthias A1 - Brähler, Caroline A1 - Kronenthaler, Corinna A1 - Wischhusen, Jörg A1 - Prelog, Martina A1 - Walles, Heike A1 - Dandekar, Thomas A1 - Dandekar, Gudrun A1 - Nietzer, Sarah L. T1 - Modular micro-physiological human tumor/tissue models based on decellularized tissue for improved preclinical testing JF - ALTEX N2 - High attrition-rates entailed by drug testing in 2D cell culture and animal models stress the need for improved modeling of human tumor tissues. In previous studies our 3D models on a decellularized tissue matrix have shown better predictivity and higher chemoresistance. A single porcine intestine yields material for 150 3D models of breast, lung, colorectal cancer (CRC) or leukemia. The uniquely preserved structure of the basement membrane enables physiological anchorage of endothelial cells and epithelial-derived carcinoma cells. The matrix provides different niches for cell growth: on top as monolayer, in crypts as aggregates and within deeper layers. Dynamic culture in bioreactors enhances cell growth. Comparing gene expression between 2D and 3D cultures, we observed changes related to proliferation, apoptosis and stemness. For drug target predictions, we utilize tumor-specific sequencing data in our in silico model finding an additive effect of metformin and gefitinib treatment for lung cancer in silico, validated in vitro. To analyze mode-of-action, immune therapies such as trispecific T-cell engagers in leukemia, as well as toxicity on non-cancer cells, the model can be modularly enriched with human endothelial cells (hECs), immune cells and fibroblasts. Upon addition of hECs, transmigration of immune cells through the endothelial barrier can be investigated. In an allogenic CRC model we observe a lower basic apoptosis rate after applying PBMCs in 3D compared to 2D, which offers new options to mirror antigen-specific immunotherapies in vitro. In conclusion, we present modular human 3D tumor models with tissue-like features for preclinical testing to reduce animal experiments. KW - modular tumor tissue models KW - invasiveness KW - bioreactor culture KW - combinatorial drug predictions KW - immunotherapies Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-231465 VL - 38 ER - TY - JOUR A1 - Köhler, Franziska A1 - Hendricks, Anne A1 - Kastner, Carolin A1 - Müller, Sophie A1 - Boerner, Kevin A1 - Wagner, Johanna C. A1 - Lock, Johan F. A1 - Wiegering, Armin T1 - Laparoscopic appendectomy versus antibiotic treatment for acute appendicitis-a systematic review JF - International Journal of Colorectal Disease N2 - Background Over the last years, laparoscopic appendectomy has progressively replaced open appendectomy and become the current gold standard treatment for suspected, uncomplicated appendicitis. At the same time, though, it is an ongoing discussion that antibiotic therapy can be an equivalent treatment for patients with uncomplicated appendicitis. The aim of this systematic review was to determine the safety and efficacy of antibiotic therapy and compare it to the laparoscopic appendectomy for acute, uncomplicated appendicitis. Methods The PubMed database, Embase database, and Cochrane library were scanned for studies comparing laparoscopic appendectomy with antibiotic treatment. Two independent reviewers performed the study selection and data extraction. The primary endpoint was defined as successful treatment of appendicitis. Secondary endpoints were pain intensity, duration of hospitalization, absence from work, and incidence of complications. Results No studies were found that exclusively compared laparoscopic appendectomy with antibiotic treatment for acute, uncomplicated appendicitis. Conclusions To date, there are no studies comparing antibiotic treatment to laparoscopic appendectomy for patients with acute uncomplicated appendicitis, thus emphasizing the lack of evidence and need for further investigation. KW - acute appendicitis KW - open appendectomy KW - laparoscopic appendectomy KW - antibiotics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266616 SN - 1432-1262 VL - 36 IS - 10 ER - TY - JOUR A1 - Kunz, Tobias C. A1 - Rühling, Marcel A1 - Moldovan, Adriana A1 - Paprotka, Kerstin A1 - Kozjak-Pavlovic, Vera A1 - Rudel, Thomas A1 - Fraunholz, Martin T1 - The Expandables: Cracking the Staphylococcal Cell Wall for Expansion Microscopy JF - Frontiers in Cellular and Infection Microbiology N2 - Expansion Microscopy (ExM) is a novel tool improving the resolution of fluorescence microscopy by linking the sample into a hydrogel that gets physically expanded in water. Previously, we have used ExM to visualize the intracellular Gram-negative pathogens Chlamydia trachomatis, Simkania negevensis, and Neisseria gonorrhoeae. Gram-positive bacteria have a rigid and thick cell wall that impedes classic expansion strategies. Here we developed an approach, which included a series of enzymatic treatments resulting in isotropic 4× expansion of the Gram-positive pathogen Staphylococcus aureus. We further demonstrate the suitability of the technique for imaging of planktonic bacteria as well as endocytosed, intracellular bacteria at a spatial resolution of approximately 60 nm with conventional confocal laser scanning microscopy. KW - high-resolution imaging KW - endosomes KW - autophagosomes KW - host-pathogen interaction KW - expansion microscopy Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232292 SN - 2235-2988 VL - 11 ER - TY - JOUR A1 - Kuhlemann, Alexander A1 - Beliu, Gerti A1 - Janzen, Dieter A1 - Petrini, Enrica Maria A1 - Taban, Danush A1 - Helmerich, Dominic A. A1 - Doose, Sören A1 - Bruno, Martina A1 - Barberis, Andrea A1 - Villmann, Carmen A1 - Sauer, Markus A1 - Werner, Christian T1 - Genetic Code Expansion and Click-Chemistry Labeling to Visualize GABA-A Receptors by Super-Resolution Microscopy JF - Frontiers in Synaptic Neuroscience N2 - Fluorescence labeling of difficult to access protein sites, e.g., in confined compartments, requires small fluorescent labels that can be covalently tethered at well-defined positions with high efficiency. Here, we report site-specific labeling of the extracellular domain of γ-aminobutyric acid type A (GABA-A) receptor subunits by genetic code expansion (GCE) with unnatural amino acids (ncAA) combined with bioorthogonal click-chemistry labeling with tetrazine dyes in HEK-293-T cells and primary cultured neurons. After optimization of GABA-A receptor expression and labeling efficiency, most effective variants were selected for super-resolution microscopy and functionality testing by whole-cell patch clamp. Our results show that GCE with ncAA and bioorthogonal click labeling with small tetrazine dyes represents a versatile method for highly efficient site-specific fluorescence labeling of proteins in a crowded environment, e.g., extracellular protein domains in confined compartments such as the synaptic cleft. KW - super-resolution microscopy (SRM) KW - click-chemistry KW - dSTORM KW - GABA-A receptor KW - genetic code expansion Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-251035 SN - 1663-3563 VL - 13 ER - TY - JOUR A1 - Krüger, Timothy A1 - Maus, Katharina A1 - Kreß, Verena A1 - Meyer-Natus, Elisabeth A1 - Engstler, Markus T1 - Single-cell motile behaviour of Trypanosoma brucei in thin-layered fluid collectives JF - The European Physical Journal E N2 - We describe a system for the analysis of an important unicellular eukaryotic flagellate in a confining and crowded environment. The parasite Trypanosoma brucei is arguably one of the most versatile microswimmers known. It has unique properties as a single microswimmer and shows remarkable adaptations (not only in motility, but prominently so), to its environment during a complex developmental cycle involving two different hosts. Specific life cycle stages show fascinating collective behaviour, as millions of cells can be forced to move together in extreme confinement. Our goal is to examine such motile behaviour directly in the context of the relevant environments. Therefore, for the first time, we analyse the motility behaviour of trypanosomes directly in a widely used assay, which aims to evaluate the parasites behaviour in collectives, in response to as yet unknown parameters. In a step towards understanding whether, or what type of, swarming behaviour of trypanosomes exists, we customised the assay for quantitative tracking analysis of motile behaviour on the single-cell level. We show that the migration speed of cell groups does not directly depend on single-cell velocity and that the system remains to be simplified further, before hypotheses about collective motility can be advanced. KW - Trypanosoma brucei KW - motile behaviour KW - fluid collectives Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-273022 SN - 1292-895X VL - 44 IS - 3 ER - TY - JOUR A1 - Krones, David A1 - Rühling, Marcel A1 - Becker, Katrin Anne A1 - Kunz, Tobias C. A1 - Sehl, Carolin A1 - Paprotka, Kerstin A1 - Gulbins, Erich A1 - Fraunholz, Martin T1 - Staphylococcus aureus α-Toxin Induces Acid Sphingomyelinase Release From a Human Endothelial Cell Line JF - Frontiers in Microbiology N2 - Staphylococcus aureus (S. aureus) is well known to express a plethora of toxins of which the pore-forming hemolysin A (α-toxin) is the best-studied cytolysin. Pore-forming toxins (PFT) permeabilize host membranes during infection thereby causing concentration-dependent effects in host cell membranes ranging from disordered ion fluxes to cytolysis. Host cells possess defense mechanisms against PFT attack, resulting in endocytosis of the breached membrane area and delivery of repair vesicles to the insulted plasma membrane as well as a concurrent release of membrane repair enzymes. Since PFTs from several pathogens have been shown to recruit membrane repair components, we here investigated whether staphylococcal α-toxin is able to induce these mechanisms in endothelial cells. We show that S. aureus α-toxin induced increase in cytosolic Ca2+ in endothelial cells, which was accompanied by p38 MAPK phosphorylation. Toxin challenge led to increased endocytosis of an extracellular fluid phase marker as well as increased externalization of LAMP1-positive membranes suggesting that peripheral lysosomes are recruited to the insulted plasma membrane. We further observed that thereby the lysosomal protein acid sphingomyelinase (ASM) was released into the cell culture medium. Thus, our results show that staphylococcal α-toxin triggers mechanisms in endothelial cells, which have been implicated in membrane repair after damage of other cell types by different toxins. KW - acid sphingomyelinase KW - staphylococcal alpha-toxin KW - sphingomyelinase release KW - lysosomal recruitment KW - Staphylococcus aureus Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244843 SN - 1664-302X VL - 12 ER - TY - THES A1 - Krimmer, Elena T1 - Agri-environment schemes and ecosystem services: The influence of different sown flower field characteristics on pollination, natural pest control and crop yield T1 - Agrarumweltmaßnahmen und Ökosystemdienstleistungen: der Einfluss unterschiedlicher Blühflächen Merkmale auf Bestäubung, natürliche Schädlingskontrolle und Erträge N2 - Insects are responsible for the major part of the ecosystem services pollination and natural pest control. If insects decline, these ecosystem services can not longer be reliably delivered. Agricultural intensification and the subsequent loss and fragmentation of habitats has among others been identified to cause insect decline. Ecological intensification aims to promote alternative and sustainable management practices in agricultural farming, for example to decrease the use of external inputs such as pesticides. Agri-environment schemes make amends for farmers if they integrate ecologically beneficial measures into their farming regime and can therefore promote ecological intensification. There is a wide variety of agri-environment schemes, but the implementation of sown flower fields on crop fields is often included. Flower fields offer foraging resources as well as nesting sites for many different insect species and should be able to support insect populations as well as to increase ecosystem services to adjacent fields. However, the potential of flower fields to exhibit these effects is depending on many factors. Among others, the age and size of the flower field can influence if and how different insects profit from the measure. Additionally, the complexity of the surrounding landscape and therefore the existing biodiversity is influencing the potential of flower fields to increase ecosystem services locally. The goal of this study is to disentangle to which degree these factors influence the ecosystem services pollination and natural pest control and if these factors interact with each other. Furthermore, it will be examined if and how flower fields and ecosystem services influence crop yield. Additional factors examined in this study are distance decay and pesticide use. The abundance of beneficial insects can decrease strongly with increasing distance to suitable habitats. Pesticide use in turn could abrogate positive effects of flower fields on beneficial insects. To examine these different aspects and to be able to make recommendations for flower field implementation, field experiments were conducted on differently composed sown flower fields and adjacent oilseed rape fields. Flower fields differed in their age and continuity as well as in their size. Additionally, flower and oilseed rape fields were chosen in landscapes with different amounts of semi-natural habitat. Oilseed rape fields adjacent to calcareous grasslands and conventional crop fields served as controls. Pollinator observations and pollen beetle and parasitism surveys were conducted in the oilseed rape fields. Additionally, different yield parameters of the oilseed rape plants were recorded. Observations were conducted and samples taken in increasing distance to the flower fields to examine distance decay functions. Spray windows were established to inspect the influence of pesticides on ecosystem services and crop yields. Linear mixed models were used for statistical analysis. The results show, that newly established flower fields with high amounts of flower cover are very attractive for pollinators. If the flower fields reached a certain size (> 1.5ha), the pollinators tended to stay in these fields and did not distribute into the surroundings. High amounts of semi-natural habitat in the surrounding landscape increased the value of small flower fields as starting points for pollinators and their subsequent spillover into crop fields. Additionally, high amounts of semi-natural habitat decreased the decay of pollinators with increasing distance to the flower fields. Based on these results, it can be recommended to establish many small flower fields in landscapes with high amounts of semi-natural habitat and large flower fields in landscapes with low amounts of semi-natural habitat. However, it is mentionable that flower fields are no substitute for perennial semi-natural habitats. These still must be actively conserved to increase pollination to crop fields. Furthermore, the lowest amount of pollen beetle infestation was found on oilseed rape fields adjacent to continuous flower fields aged older than 6 years. Flower fields and calcareous grasslands in general increased pollen beetle parasitism in adjacent oilseed rape fields compared to conventional crop fields. The threshold for effective natural pest control could only be reached in the pesticide free areas in the oilseed rape fields adjacent to continuous flower fields and calcareous grasslands. Parasitism and superparasitism declined with increasing distance to the adjacent fields in pesticide treated areas of the oilseed rape fields. However, they remained on a similar level in spray windows without pesticides. Large flower fields increased parasitism and superparasitism more than small flower fields. Flower fields generally have the potential to increase pollen beetle parasitism rates, but pesticides can abrogate these positive effects of flower fields on natural pest control. Last but not least, effects of flower fields and ecosystem services on oilseed rape yield were examined. No positive effects of pollination on oilseed rape yield could be found. Old and continuous flower fields increased natural pest control in oilseed rape fields, which in turn increased seed set and total seed weight of oilseed rape plants. The pesticide treatment had negative effects on natural pest control, but positive effects on crop yield. Pollination and natural pest control decreased with increasing distance to the field edge, but fruit set slightly increased. The quality of the field in terms of soil and climatic conditions did not influence the yield parameters examined in this study. Yield formation in oilseed rape plants is a complex process with many factors involved, and it is difficult to disentangle indirect effects of flower fields on yield. However, perennial flower fields can promote ecological intensification by increasing crop yield via natural pest control. This study contributes to a better understanding of the effects of differently composed flower fields on pollination, natural pest control and oilseed rape yield. N2 - Insekten sind für einen Großteil der Ökosystemdienstleistungen Bestäubung und natürliche Schädlingskontrolle zuständig. Schwinden die Insekten, so können diese Dienstleistungen nicht mehr zuverlässig gewährleistet werden. Als Ursachen für den Rückgang an Insekten wurde unter anderem die Intensivierung der Landwirtschaft und damit einhergehend der Verlust und die Fragmentierung von Lebensraum identifiziert. Ökologische Intensivierung hat das Ziel, alternative und nachhaltige Bewirtschaftungsmethoden in der Landwirtschaft zu fördern und beispielsweise den Einsatz von Spritzmitteln zu verringern. Agrarumweltmaßnahmen entschädigen Landwirte, wenn sie ökologisch wertvolle Maßnahmen in ihren Betrieb integrieren und können dadurch ökologische Intensivierung unterstützen. Die Bandbreite an Agrarumweltmaßnahmen ist groß, beinhaltet aber häufig das Anlegen von Blühflächen auf Ackerflächen. Blühflächen liefern Nahrungsressourcen und Lebensraum für eine Vielzahl von Insekten und sollten daher in der Lage sein Insektenpopulationen zu unterstützen und Ökosystemdienstleistungen auf angrenzenden Feldern zu verstärken. Jedoch ist das ökologische Potential von Blühflächen von einer Vielzahl von Faktoren abhängig. Unter anderem können das Alter und die Größe der Blühfläche entscheidend beeinflussen, inwiefern unterschiedliche Insektengruppen profitieren. Zusätzlich hat die Landschaftskomplexität der direkten Umgebung, und damit die potentiell vorhandene Biodiversität, großen Einfluss auf die Fähigkeit von Blühflächen Ökosystemdienstleistungen lokal zu erhöhen. In dieser Studie geht es darum zu entschlüsseln, wie sich diese verschiedenen Faktoren sich auf die beiden Ökosystemdienstleistungen Bestäubung und natürliche Schädlingskontrolle auswirken und ob sie sich gegenseitig beeinflussen. Zusätzlich soll untersucht werden, inwiefern Blühflächen und Ökosystemdienstleistungen Erträge beeinflussen können. Weitere in dieser Studie untersuchte Einflussfaktoren sind die Distanz zur Blühfläche und der Einsatz von Pestiziden. Die Abundanz von Nützlingen kann mit der Distanz zu geeigneten Habitaten stark abnehmen. Der Einsatz von Spritzmitteln wiederum könnte die positiven Einflüsse der Blühflächen auf Nützlinge aufheben. Um diese verschiedenen Aspekte zu untersuchen und letztendlich Empfehlung für die Etablierung von Blühflächen geben zu können, wurden Feldversuche auf Blühflächen mit unterschiedlicher Beschaffenheit und auf angrenzenden Rapsflächen durchgeführt. Die Blühflächen unterschieden sich hierbei in ihrem Alter und ihrer Kontinuität. Zusätzlich wurden Blühflächen mit unterschiedlicher Größe getestet. Außerdem wurden die Blühflächen und ihre benachbarten Rapsfelder so ausgewählt, dass sie sich in Landschaften mit unterschiedlichem Anteil an halbnatürlichen Habitaten befinden. Rapsflächen neben Kalkmagerrasen und Äckern mit konventionellen Feldfrüchten dienten als Kontrollflächen. Auf den Rapsflächen wurden Bestäuberbeobachtungen sowie Aufnahmen von Rapsglanzkäferbefall und deren Parasitierung durchgeführt. Zusätzlich wurden verschiedene Ertragsparameter von Raps aufgenommen. Die Untersuchungen fanden jeweils in unterschiedlichen Distanzen zur Blühfläche innerhalb des Rapsfeldes statt, um Distanz-Abnahme Funktionen zu untersuchen. Spritzfenster wurden etabliert, um den Einfluss von Pestiziden auf Ökosystemdienstleistungen und Erträge zu untersuchen. Für die statistische Auswertung wurden lineare gemischte Modelle verwendet. Die Ergebnisse haben zum einen gezeigt, dass frisch angelegte Blühflächen mit hoher Blütendeckung sehr attraktiv für Bestäuber sind. Jedoch blieben die Bestäuber in den Blühflächen, wenn diese eine gewisse Größe hatten (> 1.5ha) und verteilten sich nicht auf die umgebenden Flächen. Ein hoher Anteil an halbnatürlichen Habitaten in der umgebenden Landschaft erhöhte den Wert von kleinen Blühflächen als Ausgangspunkt für Bestäuber und ihren anschließenden Übergang auf Ackerflächen. Hohe Mengen an halbnatürlichen Habitaten verringerten außerdem den Rückgang der Bestäuber mit steigender Entfernung zur Blühfläche. Auf Grundlage dieser Ergenisse wäre es zu empfehlen, kleine Blühflächen in Landschaften mit viel halbnatürlichem Habitat und große Blühflächen in Landschaften mit wenig halbnatürlichem Habitat anzulegen. Außerdem ist anzumerken, dass Blühflächen keinen adequaten Ersatz für dauerhafte halbantürliche Habitate darstellen. Diese müssen weiterhin aktiv geschützt und erhalten werden, um Bestäubung auf Ackerflächen zu fördern. Des Weiteren wurde auf Rapsflächen neben kontinuierlichen Blühflächen mit einem Alter über 6 Jahre der niedrigste Befall mit Rapsglanzkäferlarven festgestellt. Blühflächen und Kalkmagerrasen erhöhten die Parasitierung von Rapsglanzkäfern in benachbarten Rapsflächen im Vergleich zu Rapsflächen die neben Ackerflächen liegen. Der Schwellenwert für eine effektive natürliche Schädlingskontrolle wurde nur in den pestizidfreien Bereichen in Rapsflächen neben kontinuierlichen Blühflächen und Kalkmagerasen erreicht. In mit Pestiziden behandelten Bereichen nahmen Parasitismus und Superparasitismus mit zunehmender Entfernung zum benachbarten Feld ab. In den Spritzfenstern ohne Pestizide blieben sie jedoch auf dem gleichen Niveau. Große Blühflächen erhöhten Parasitismus und Superparasitismus mehr als kleine. Insgesamt können Blühflächen die Parasitierungsraten von Rapsglanzkäfern auf Rapsflächen erhöhen, jedoch können Pestizide diese positiven Effekte aufheben. Zuletzt wurden die Effekte von Blühflächen und Ökosystemdienstleistungen auf den Rapsertrag untersucht. Hier stellte sich heraus, dass Bestäubung keine positiven Effekte auf den Rapsertrag hatte. Alte und kontinuierliche Blühflächen erhöhten die natürliche Schädlingskontrolle in den Rapsfeldern, welche wiederrum den Samenansatz und das absolute Samengewicht erhöhten. Die Behandlung mit Pestiziden hatte negative Asuwirkungen auf natürliche Schädlingskontrolle, aber positive Auswirkungen auf den Ertrag. Bestäubung und natürliche Schädlingskontrolle nahmen mit der zunehmenden Entfernung zum Feldrand ab, aber der Fruchtansatz nahm leicht zu. Die Feldqualität hatte keine Auswirkungen auf die im Modell untersuchten Rapsertrag Messwerte. Ertragsbildung bei Rapspflanzen ist ein komplexer Vorgang an dem viele Faktoren beteiligt sind. Mehrjährige Blühflächen können ökologische Intensivierung fördern indem sie den Ertrag durch natürliche Schädlingskontrolle erhöhen. Diese Studie leistet einen wertvollen Beitrag zum besseren Verständnis der Auswirkungen von unterschiedlich beschaffenen Blühflächen auf Bestäubung, natürliche Schädlingskontrolle und Rapsertrag. KW - Ökologie KW - Agrarumweltmaßnahmen KW - Ökosystemdienstleistung Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-206577 ER - TY - JOUR A1 - Kriegel, Peter A1 - Matevski, Dragan A1 - Schuldt, Andreas T1 - Monoculture and mixture-planting of non-native Douglas fir alters species composition, but promotes the diversity of ground beetles in a temperate forest system JF - Biodiversity and Conservation N2 - Planting non-native tree species, like Douglas fir in temperate European forest systems, is encouraged to mitigate effects of climate change. However, Douglas fir monocultures often revealed negative effects on forest biota, while effects of mixtures with native tree species on forest ecosystems are less well understood. We investigated effects of three tree species (Douglas fir, Norway spruce, native European beech), on ground beetles in temperate forests of Germany. Beetles were sampled in monocultures of each tree species and broadleaf-conifer mixtures with pitfall traps, and environmental variables were assessed around each trap. We used linear mixed models in a two-step procedure to disentangle effects of environment and tree species identity on ground beetle abundance, species richness, functional diversity and species assemblage structure. Contradictory to our expectations, ground beetle abundance and functional diversity was highest in pure Douglas fir stands, while tree mixtures showed intermediate values between pure coniferous and pure beech stands. The main drivers of these patterns were only partially dependent on tree species identity, which highlights the importance of structural features in forest stands. However, our study revealed distinct shifts in assemblage structure between pure beech and pure Douglas fir stands, which were only partially eased through mixture planting. Our findings suggest that effects of planting non-native trees on associated biodiversity can be actively modified by promoting beneficial forest structures. Nevertheless, integrating non-native tree species, even in mixtures with native trees, will invariably alter assemblage structures of associated biota, which can compromise conservation efforts targeted at typical species composition. KW - mixed-species forestry KW - exotic species KW - Pseudotsuga menziesii KW - functional diversity KW - insects KW - microhabitats Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-269017 SN - 1572-9710 VL - 30 IS - 5 ER - TY - JOUR A1 - Kriegel, Peter A1 - Fritze, Michael‐Andreas A1 - Thorn, Simon T1 - Surface temperature and shrub cover drive ground beetle (Coleoptera: Carabidae) assemblages in short‐rotation coppices JF - Agricultural and Forest Entomology N2 - Increasing demand for biomass has led to an on‐going intensification of fuel wood plantations with possible negative effects on open land biodiversity. Hence, ecologists increasingly call for measures that reduce those negative effects on associated biodiversity. However, our knowledge about the efficiency of such measures remains scarce. We investigated the effects of gap implementation in short rotation coppices (SRCs) on carabid diversity and assemblage composition over 3 years, with pitfall traps in gaps, edges and interiors. In parallel, we quantified soil surface temperature, shrub‐ and herb cover. Edges had the highest number of species and abundances per trap, whereas rarefied species richness was significantly lower in short rotation coppice interiors than in other habitat types. Carabid community composition differed significantly between habitat types. The main environmental drivers were temperature for number of species and abundance and shrub cover for rarefied species richness. We found significantly higher rarefied species richness in gaps compared with interiors. Hence, we argue that gap implementation benefits overall diversity in short rotation coppices. Furthermore, the differences in species community composition between habitat types through increased species turnover support carabid diversity in short rotation coppices. These positive effects were largely attributed to microclimate conditions. However, to maintain positive effects, continuous management of herb layer might be necessary. KW - Carabidae KW - fuel wood KW - short‐rotation coppice KW - shrub‐cover KW - temperature Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-239873 VL - 23 IS - 4 SP - 400 EP - 410 ER - TY - JOUR A1 - Kramer, Susanne A1 - Meyer-Natus, Elisabeth A1 - Stigloher, Christian A1 - Thoma, Hanna A1 - Schnaufer, Achim A1 - Engstler, Markus T1 - Parallel monitoring of RNA abundance, localization and compactness with correlative single molecule FISH on LR White embedded samples JF - Nucleic Acids Research N2 - Single mRNA molecules are frequently detected by single molecule fluorescence in situ hybridization (smFISH) using branched DNA technology. While providing strong and background-reduced signals, the method is inefficient in detecting mRNAs within dense structures, in monitoring mRNA compactness and in quantifying abundant mRNAs. To overcome these limitations, we have hybridized slices of high pressure frozen, freeze-substituted and LR White embedded cells (LR White smFISH). mRNA detection is physically restricted to the surface of the resin. This enables single molecule detection of RNAs with accuracy comparable to RNA sequencing, irrespective of their abundance, while at the same time providing spatial information on RNA localization that can be complemented with immunofluorescence and electron microscopy, as well as array tomography. Moreover, LR White embedding restricts the number of available probe pair recognition sites for each mRNA to a small subset. As a consequence, differences in signal intensities between RNA populations reflect differences in RNA structures, and we show that the method can be employed to determine mRNA compactness. We apply the method to answer some outstanding questions related to trans-splicing, RNA granules and mitochondrial RNA editing in single-cellular trypanosomes and we show an example of differential gene expression in the metazoan Caenorhabditis elegans. KW - mRNA Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230647 VL - 49 IS - 3 ER - TY - JOUR A1 - Kouhestani, Dina A1 - Geis, Maria A1 - Alsouri, Saed A1 - Bumm, Thomas G. P. A1 - Einsele, Hermann A1 - Sauer, Markus A1 - Stuhler, Gernot T1 - Variant signaling topology at the cancer cell–T-cell interface induced by a two-component T-cell engager JF - Cellular & Molecular Immunology N2 - No abstract available. KW - immunotherapy KW - tumour immunology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-241189 VL - 18 ER - TY - JOUR A1 - Kessie, David K. A1 - Lodes, Nina A1 - Oberwinkler, Heike A1 - Goldman, William E. A1 - Walles, Thorsten A1 - Steinke, Maria A1 - Gross, Roy T1 - Activity of Tracheal Cytotoxin of Bordetella pertussis in a Human Tracheobronchial 3D Tissue Model JF - Frontiers in Cellular and Infection Microbiology N2 - Bordetella pertussis is a highly contagious pathogen which causes whooping cough in humans. A major pathophysiology of infection is the extrusion of ciliated cells and subsequent disruption of the respiratory mucosa. Tracheal cytotoxin (TCT) is the only virulence factor produced by B. pertussis that has been able to recapitulate this pathology in animal models. This pathophysiology is well characterized in a hamster tracheal model, but human data are lacking due to scarcity of donor material. We assessed the impact of TCT and lipopolysaccharide (LPS) on the functional integrity of the human airway mucosa by using in vitro airway mucosa models developed by co-culturing human tracheobronchial epithelial cells and human tracheobronchial fibroblasts on porcine small intestinal submucosa scaffold under airlift conditions. TCT and LPS either alone and in combination induced blebbing and necrosis of the ciliated epithelia. TCT and LPS induced loss of ciliated epithelial cells and hyper-mucus production which interfered with mucociliary clearance. In addition, the toxins had a disruptive effect on the tight junction organization, significantly reduced transepithelial electrical resistance and increased FITC-Dextran permeability after toxin incubation. In summary, the results indicate that TCT collaborates with LPS to induce the disruption of the human airway mucosa as reported for the hamster tracheal model. KW - tracheal cytotoxin KW - airway epithelia KW - tissue model KW - ciliostasis KW - tight junction KW - Bordetella pertussis Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-222736 SN - 2235-2988 VL - 10 ER - TY - THES A1 - Kehrberger, Sandra T1 - Effects of climate warming on the timing of flowering and emergence in a tritrophic relationship: plants - bees - parasitoids T1 - Auswirkungen der Klimaerwärmung auf die zeitliche Regulierung der Blüte und des Schlupfes in einer tritrophischen Beziehung: Pflanzen - Bienen - Parasitoide N2 - The right timing of phenological events is crucial for species fitness. Species should be highly synchronized with mutualists, but desynchronized with antagonists. With climate warming phenological events advance in many species. However, often species do not respond uniformly to warming temperatures. Species-specific responses to climate warming can lead to asynchrony or even temporal mismatch of interacting species. A temporal mismatch between mutualists, which benefit from each other, can have negative consequences for both interaction partners. For host-parasitoid interactions temporal asynchrony can benefit the host species, if it can temporally escape its parasitoid, with negative consequences for the parasitoid species, but benefit the parasitoid species if it increases synchrony with its host, which can negatively affect the host species. Knowledge about the drivers of phenology and the species-specific responses to these drivers are important to predict future effects of climate change on trophic interactions. In this dissertation I investigated how different drivers act on early flowering phenology and how climate warming affects the tritrophic relationship of two spring bees (Osmia cornuta & Osmia bicornis), an early spring plant (Pulsatilla vulgaris), which is one of the major food plants of the spring bees, and three main parasitoids of the spring bees (Cacoxenus indagator, Anthrax anthrax, Monodontomerus). In Chapter II I present a study in which I investigated how different drivers and their change over the season affect the reproductive success of an early spring plant. For that I recorded on eight calcareous grasslands around Würzburg, Germany the intra-seasonal changes in pollinator availability, number of co-flowering plants and weather conditions and studied how they affect flower visitation rates, floral longevity and seed set of the early spring plant P. vulgaris. I show that bee abundances and the number of hours, which allowed pollinator foraging, were low at the beginning of the season, but increased over time. However, flower visitation rates and estimated total number of bee visits were higher on early flowers of P. vulgaris than later flowers. Flower visitation rates were also positively related to seed set. Over time and with increasing competition for pollinators by increasing numbers of co-flowering plants flower visitation rates decreased. My data shows that a major driver for early flowering dates seems to be low interspecific competition for pollinators, but not low pollinator abundances and unfavourable weather conditions. Chapter III presents a study in which I investigated the effects of temperature on solitary bee emergence and on the flowering of their food plant and of co-flowering plants in the field. Therefore I placed bee cocoons of two spring bees (O. cornuta & O. bicornis) on eleven calcareous grasslands which differed in mean site temperature. On seven of these grasslands the early spring plant P. vulgaris occurred. I show that warmer temperatures advanced mean emergence in O. cornuta males. However, O. bicornis males and females of both species did not shift their emergence. Compared to the bees P. vulgaris advanced its flowering phenology more strongly with warmer temperatures. Co-flowering plants did not shift flowering onset. I suggest that with climate warming the first flowers of P. vulgaris face an increased risk of pollinator limitation whereas for bees a shift in floral resources may occur. In Chapter IV I present a study in which I investigated the effects of climate warming on host-parasitoid relationships. I studied how temperature and photoperiod affect emergence phenology in two spring bees (O. cornuta & O. bicornis) and three of their main parasitoids (C. indagator, A. anthrax, Monodontomerus). In a climate chamber experiment with a crossed design I exposed cocoons within nest cavities and cocoons outside of nest cavities to two different temperature regimes (long-term mean of Würzburg, Germany and long-term mean of Würzburg + 4 °C) and three photoperiods (Würzburg vs. Snåsa, Norway vs. constant darkness) and recorded the time of bee and parasitoid emergence. I show that warmer temperatures advanced emergence in all studied species, but bees advanced less strongly than parasitoids. Consequently, the time period between female bee emergence and parasitoid emergence decreased in the warm temperature treatment compared to the cold one. Photoperiod influenced the time of emergence only in cocoons outside of nest cavities (except O. bicornis male emergence). The data also shows that the effect of photoperiod compared to the effect of temperature on emergence phenology was much weaker. I suggest that with climate warming the synchrony of emergence phenologies of bees and their parasitoids will amplify. Therefore, parasitism rates in solitary bees might increase which can negatively affect reproductive success and population size. In this dissertation I show that for early flowering spring plants low interspecific competition for pollinators with co-flowering plants is a major driver of flowering phenology, whereas other drivers, like low pollinator abundances and unfavourable weather conditions are only of minor importance. With climate warming the strength of different drivers, which act on the timing of phenological events, can change, like temperature. I show that warmer temperatures advance early spring plant flowering more strongly than bee emergence and flowering phenology of later co-flowering plants. Furthermore, I show that warmer temperatures advance parasitoid emergence more strongly than bee emergence. Whereas temperature changes can lead to non-uniform temporal shifts, I demonstrate that geographic range shifts and with that altered photoperiods will not change emergence phenology in bees and their parasitoids. In the tritrophic system I investigated in this dissertation climate warming may negatively affect the reproductive success of the early spring plant and the spring bees but not of the parasitoids, which may even benefit from warming temperatures. N2 - Der richtige Zeitpunkt von phänologischen Ereignissen ist maßgeblich für das Überleben und die Fortpflanzung einer Art. Arten sollten eine möglichst hohe Synchronisation mit Mutualisten aufweisen, aber eine möglichst geringe mit Antagonisten. Die Klimaerwärmung führt dazu, dass sich bei vielen Arten phänologische Ereignisse verfrühen. Allerdings reagieren Arten unterschiedlich auf wärmere Temperaturen. Artspezifische Reaktionen auf die Klimaerwärmung können zu Asynchronität oder sogar zu zeitlicher Diskrepanz bei interagierenden Arten führen. Eine zeitliche Diskrepanz zwischen Mutualisten, die voneinander profitieren, kann sich negativ auf beide Interaktionspartner auswirken. Bei Wirt-Parasitoid Beziehungen kann der Wirt von einer zeitlichen Diskrepanz profitieren, wenn er seinem Parasitoid zeitlich entfliehen kann, was wiederum negative Folgen für den Parasitoid haben kann. Jedoch kann der Parasitoid profitieren, wenn er die Synchronisation mit seinem Wirt erhöhen kann, was wiederum den Wirt negativ beeinflussen kann. Das Wissen über die Treiber von phänologischen Ereignissen und die artspezifischen Reaktionen auf diese Treiber sind von Bedeutung um die Auswirkungen des Klimawandels auf trophische Beziehungen vorherzusagen. In meiner Doktorarbeit habe ich untersucht, wie verschiedene Treiber mit einer frühen Blüte zusammenhängen und wie der Klimawandel die tritrophische Beziehung von zwei Frühlingsbienen (Osmia cornuta & Osmia bicornis), einer Frühlingspflanzenart (Pulsatilla vulgaris), die eine der wichtigen Futterpflanzen der Bienen ist, und der drei Hauptparasitoiden der Frühlingsbienen (Cacoxenus indagator, Anthrax anthrax, Monodontomerus) beeinflusst. In Kapitel II präsentiere ich eine Studie, in der ich den Einfluss verschiedener Treiber und ihre saisonale Veränderung auf den Fortpflanzungserfolg einer Frühlingspflanzenart untersucht habe. Dazu habe ich auf acht Kalkmagerrasen bei Würzburg (Deutschland) die innersaisonalen Veränderungen der Bestäuberverfügbarkeit, der Anzahl an gleichzeitig blühenden Pflanzenarten und die Wetterbedingungen aufgezeichnet. Des Weiteren habe ich erforscht wie diese Faktoren die Blütenbesuchsrate, die Blütenlanglebigkeit und den Samenansatz der Frühlingspflanze P. vulgaris beeinflussen. Ich konnte zeigen, dass die Anzahl an Bienen und die Anzahl an Stunden, die ein Furagieren von Bestäubern ermöglicht hätten, am Anfang der Saison niedrig waren und mit der Zeit zunahmen. Jedoch war die Blütenbesuchsrate und die geschätzte Anzahl an Bienenbesuchen höher bei frühen als bei späten P. vulgaris Blüten. Die Blütenbesuchsrate wirkte sich auch positiv auf den Samenansatz aus. Die Blütenbesuchsrate nahm mit der Zeit und mit zunehmender Konkurrenz um Bestäuber durch eine zunehmende Anzahl an gleichzeitig blühenden Pflanzenarten ab. Meine Daten zeigen, dass ein Hauptreiber von frühen Blühzeitpunkten die geringe zwischenartliche Konkurrenz um Bestäuber ist, aber nicht die niedrige Bestäuberanzahl und ungünstige Wetterbedingungen. Kapitel III präsentiert eine Studie, in welcher ich die Auswirkungen der Temperatur auf den Schlupf von Solitärbienen und die Blüte ihrer Futterpflanzen und gleichzeitig blühenden Pflanzen im Freiland untersucht habe. Dafür habe ich Bienenkokons von zwei Frühlingsbienen (O. cornuta & O. bicornis) auf elf Kalkmagerrasen, die sich in der mittleren Flächentemperatur unterschieden, platziert. Auf sieben dieser Kalkmagerrasen kam die Frühlingspflanzenart P. vulgaris vor. Ich konnte zeigen, dass wärmere Temperaturen den mittleren Schlupf von O. cornuta Männchen verfrühen. Die Männchen von O. bicornis und die Weibchen beider Arten haben ihren Schlupfzeitpunkt jedoch nicht verschoben. Im Vergleich zu den Bienen verfrühte P. vulgaris seine Blühphänologie bei warmen Temperaturen stärker. Die gleichzeitig blühenden Pflanzenarten verschoben ihren Blühbeginn nicht. Die Daten zeigen, dass wärmere Temperaturen den Bienenschlupf weniger stark verfrühen als die Blüte ihrer Futterpflanze. Das lässt darauf schließen, dass mit dem Klimawandel die ersten Blüten von P. vulgaris ein erhöhtes Risiko haben nicht bestäubt zu werden, während die Bienen möglicherweise auf andere Blühressourcen ausweichen müssen. Kapitel IV beschreibt eine Studie, in welcher ich die Auswirkungen der Klimaerwärmung auf Wirt-Parasitoid Beziehungen untersucht habe. Dabei habe ich die Auswirkungen von Temperatur und Photoperiode auf die Schlupfphänologie zweier Frühlingsbienen (O. cornuta & O. bicornis) und drei ihrer Hauptparasitoide (C. indagator, A. anthrax, Monodontomerus) erforscht. In einem Klimakammerexperiment mit gekreuztem Design habe ich Kokons in Nesthöhlen und Kokons außerhalb von Nesthöhlen, zwei verschiedenen Temperaturregimen (Langzeitmittel von Würzburg, Deutschland und Langzeitmittel von Würzburg + 4 °C) und drei Photoperioden (Würzburg, Deutschland contra Snåsa, Norwegen contra Dauerdunkel) ausgesetzt und die Zeitpunkte des Bienen- und Parasitoidenschlupfes aufgezeichnet. Ich konnte zeigen, dass warme Temperaturen in allen untersuchten Arten den Schlupfzeitpunkt verfrühten, jedoch bei den Bienen weniger stark als bei den Parasitoiden. Eine Folge daraus ist, dass sich die Zeitspanne zwischen dem Schlupf der Bienenweibchen und dem Schlupf der Parasitoide im warmen Temperaturregime im Vergleich zum kalten verkürzte. Die Photoperiode hatte auf den Zeitpunkt des Schlupfes nur in Kokons außerhalb von Nisthöhlen einen Effekt (außer beim Schlupf von O. bicornis Männchen). Die Daten zeigen auch, dass der Effekt der Photoperiode auf die Schlupfphänologie im Vergleich zu dem Effekt der Temperatur viel schwächer war. Daraus schließe ich, dass sich im Zuge der Klimaerwärmung die Synchronisation der Schlupfphänologien von Bienen und ihren Parasitoiden verstärken wird. Eine Folge davon könnten erhöhte Parasitierungsraten bei Solitärbienen sein, welche den Reproduktionserfolg und die Populationsgröße negativ beeinflussen können. In dieser Doktorarbeit habe ich gezeigt, dass einer der Haupttreiber einer frühen Blüte bei Frühlingspflanzen geringe zwischenartliche Konkurrenz um Bestäuber mit später gleichzeitig blühenden Pflanzenarten ist, während andere Treiber, wie geringe Bestäuberabundanzen und ungünstige Wetterbedingungen nur von geringer Bedeutung sind. Im Zuge des Klimawandels könnte sich die Stärke verschiedener Treiber, die den Zeitpunkt von phänologischen Ereignissen beeinflussen, verändern. Ich konnte außerdem zeigen, dass wärmere Temperaturen die Blüte von frühen Frühlingspflanzen stärker verfrühen, als den Schlupf von Bienen und die Blüte von später gleichzeitig blühenden Pflanzenarten. Des Weiteren zeigte ich, dass wärmere Temperaturen den Schlupf von Parasitoiden stärker verfrühen als den Schlupf der Bienen. Ich konnte zeigen, dass während Temperaturveränderungen zu verschieden starken zeitlichen Verschiebungen führen können, Verschiebungen von geografischen Verbreitungsgebieten und damit geänderten Photoperioden die Schlupfphänologie von Bienen und ihren Parasitoiden wahrscheinlich nicht ändern werden. In dem tritrophischen System, das ich in dieser Doktorarbeit untersucht habe, könnte die Erwärmung des Klimas den Fortpflanzungserfolg der frühen Frühlingspflanze und der Frühlingsbienen negativ beeinflussen, aber wahrscheinlich nicht die der Parasitoide, die vielleicht sogar davon profitieren können. KW - Biene KW - Klimaänderung KW - Interaktion KW - Parasitoid KW - Pflanzen KW - Klimaerwärmung KW - Mutualismus KW - Antagonismus KW - Synchronisation KW - Phänologie Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-213932 ER - TY - JOUR A1 - Kastner, Carolin A1 - Hendricks, Anne A1 - Deinlein, Hanna A1 - Hankir, Mohammed A1 - Germer, Christoph-Thomas A1 - Schmidt, Stefanie A1 - Wiegering, Armin T1 - Organoid Models for Cancer Research — From Bed to Bench Side and Back JF - Cancers N2 - Simple Summary Despite significant strides in multimodal therapy, cancers still rank within the first three causes of death especially in industrial nations. A lack of individualized approaches and accurate preclinical models are amongst the major barriers that limit the development of novel therapeutic options and drugs. Recently, the 3D culture system of organoids was developed which stably retains the genetic and phenotypic characteristics of the original tissue, healthy as well as diseased. In this review, we summarize current data and evidence on the relevance and reliability of such organoid culture systems in cancer research, focusing on their role in drug investigations (in a personalized manner). Abstract Organoids are a new 3D ex vivo culture system that have been applied in various fields of biomedical research. First isolated from the murine small intestine, they have since been established from a wide range of organs and tissues, both in healthy and diseased states. Organoids genetically, functionally and phenotypically retain the characteristics of their tissue of origin even after multiple passages, making them a valuable tool in studying various physiologic and pathophysiologic processes. The finding that organoids can also be established from tumor tissue or can be engineered to recapitulate tumor tissue has dramatically increased their use in cancer research. In this review, we discuss the potential of organoids to close the gap between preclinical in vitro and in vivo models as well as clinical trials in cancer research focusing on drug investigation and development. KW - cancer KW - tumor disease KW - organoid KW - patient-derived organoid (PDOs) KW - patient-derived tumor organoid (PDTO) Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246307 SN - 2072-6694 VL - 13 IS - 19 ER -