Zytokin-abhängige Regulation der Genexpression von Aggrekanasen und bone morphogenetic proteins in arthrotischen Synovialfibroblasten

Diese Arbeit befasst sich mit der Bedeutung der Synovialfibroblasten für die Entstehung der Arthrose. In kultivierten Synovialfibroblasten von 5 Arthrosepatienten konnte mittels Polymerase chain reaction (PCR)-Analyse gezeigt werden, dass anabole Wachstumsfaktoren- die Bone morphogenetic proteins (BMPs)- und katabole matrixdegradierende Proteasen- die Aggrekanasen- von Synovialfibroblasten exprimiert wurden. Außerdem wurde beobachtet, dass die Genexpression der Aggrekanasen und BMPs teilweise durch Zytokine reguliert wurde. Während die Genexpression der Aggrekanase-1 durch die Zytokine Interleukin-1 beta, Tumornekrosefaktor alpha und Transforming growth factor beta stimuliert wurde, führten die gleichen Zytokine zu einer Suppression der Genexpression von BMP-2 und BMP-4. Damit heben die Ergebnisse dieser Arbeit die pathogenetische Bedeutung der Synovialfibroblasten für die Arthroseentstehung als regulierbare Synthesestätten anaboler Wachstumsfaktoren und kataboler Proteasen hervor

The early bee catches the flower - circadian rhythmicity influences learning performance in honey bees, Apis mellifera

Circadian rhythmicity plays an important role for many aspects of honey bees’ lives. However, the question whether it also affects learning and memory remained unanswered. To address this question, we studied the effect of circadian timing on olfactory learning and memory in honey bees Apis mellifera using the olfactory conditioning of the proboscis extension reflex paradigm. Bees were differentially conditioned to odours and tested for their odour learning at four different “Zeitgeber” time points. We show that learning behaviour is influenced by circadian timing. Honey bees perform best in the morning compared to the other times of day. Additionally, we found influences of the light condition bees were trained at on the olfactory learning. This circadian-mediated learning is independent from feeding times bees were entrained to, indicating an inherited and not acquired mechanism. We hypothesise that a co-evolutionary mechanism between the honey bee as a pollinator and plants might be the driving force for the evolution of the time-dependent learning abilities of bees

Social conferencing in a virtual world: the innovative approach of the virtual world conference

Over the last five years, virtual world platforms have proliferated, from ActiveWorlds to Second Life to OpenSim to Olive, a range of platforms that allow large numbers of users to coalesce around virtual structures over the web are being used widely. As a result of distributed groups of researchers working on shared research problems, cost savings due to high costs of petrol and travelling and natural international incidents such as the volcano eruption in Iceland researchers and industrialists are looking for other methods for coming together. In particular, the costs of international travel are high and many multinational companies are looking for ways to reduce costs, at the same time the pressures on the environment are extreme due to climate change so efforts to reduce carbon emissions are similarly pointing to a future world with reduced travel and increasing expense for air travel. For these reasons, virtual world conferencing is becoming a popular solution, it has the immersion to make users feel engaged and part of the crowd, but has the ease of access and low costs that allows participants to take part from their offices or homes or on the move without missing out on the socializing aspects of the conference, and still attaining the main objective of bringing together a distributed group of participants from around the world. However, one of the major issues with using virtual worlds to support collaboration lies in the limits of the physical world itself in the shape of time zones; while users within a continent can relatively easily overcome the time zone barriers, when working between several continents 6-8 hours differences can be difficult to reconcile. The authors organized a purely virtual world conference to bring together top international researchers in the field of virtual world research and development from academia and industry, and at the same time use the opportunity to test out the theory that virtual world conferences can be as engaging and productive as physically held conferences, whilst reducing the costs and allowing the participation of the delegates in three different time zones to reflect the challenges of timings between the three main regions of the world: East, Central and West. This paper outlines the successes and challenges of adopting this approach. It includes analyses of questionnaires that were filled out by attendees, in an attempt to confirm or disprove the central hypothesis that virtual world conferences can support engaging and effective conferencing. The paper closes by presenting novel ideas for future conferences resulting from the attendees’ feedback and by discussing particular enhancements for the following edition of the conference

Die Entwicklung ausgewaehlter Kosten des Lebensunterhalts in Haushalten mit steigender Personenzahl Kalkulationen mit Haushaltsmodellen im Hinblick auf die Regelsatzleistungen nach dem Bundessozialhilfegese

SIGLEBibliothek Weltwirtschaft Kiel C 136,169 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman