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Das duktale Adenokarzinom des Pankreas stellt weiterhin trotz aller medizinischen Entwicklungen eine Herausforderung in der Diagnostik und Therapie bei einer nahezu identischen Inzidenz und Mortalität dar. Auch die Genese der Erkrankung ist bis zum heutigen Tag nicht geklärt. Als eine mögliche Ursache wird das inflammatorische Mikromilieu diskutiert, bzgl. dessen Entstehung und Aufrechterhaltung ebenfalls noch Unklarheiten bestehen. Als möglicher Trigger hierfür kommen die endosomalen Toll like-Rezeptoren 7 und 8 in Frage, die sowohl in ihrer Immunfunktion virale RNA-Bestandteile, so genannte pathogen-associated molecular patterns, als auch damage-associated molecular patterns, d.h. RNA-Fragmente von geschädigten oder sterbenden Zellen erkennen können. Durch ihre Stimulation kommt es zu einer Immunantwort. Im Rahmen dieser Arbeit wurde die Auswirkung der Stimulation von TLR 7 und TLR 8 exprimierenden PANC-1-Zellen bzgl. des Wachstumsverhaltens und der Chemosensibilität auf 5-FU untersucht. Es konnte gezeigt werden, dass mit einem spezifischen TLR7 und TLR8-Agonisten (R848) das Wachstum signifikant im Vergleich zu unbehandelten Zellen gesteigert werden konnte. Das dieser Effekt abhängig von der Expression von TLR7 und TLR8 war, konnte dadurch bewiesen werden, dass PANC-1 Zellen ohne die Expression von TLR7 oder TLR8 sowie mittels siRNA-Knockdown für TLR7 oder TLR8 behandelte TLR7- oder TLR8-exprimierende PANC1-Zellen kein gesteigertes Wachstum zeigten. Die Chemosensibilität auf 5-FU in einer LD50-Dosierung war bei den stimulierten Zellen im Vergleich zu den unstimulierten Zellen signifikant reduziert. Auf molekularer Ebene war ein Trend hinsichtlich eines Anstiegs Apoptose-inhibierender, Wachstums-fördernder und Inflammation-aufrechterhaltender Faktoren (IL-6, NF-kB, COX-2) zu erkennen. Zusammenfassend konnte gezeigt werden, dass die Stimulation von Toll like-Rezeptoren 7 und 8 exprimierenden Pankreaskarzinomzellen mit einem weiteren Tumorwachstum sowie einer reduzierten Chemosensibilität sowie daraus resultierenden schlechten Therapieansprechen vergesellschaftet sein können. / Ductal adenocarcinoma of the pancreas continues to present a challenge in diagnosis and therapy with an almost identical incidence and mortality despite all medical developments. The genesis of the disease has also not been clarified to this day. The inflammatory microenvironment is discussed as a possible cause, but there are still uncertainties regarding its development and maintenance. A possible trigger for this are the endosomal toll-like receptors 7 and 8, which in their immune function recognize viral RNA components, so-called pathogen-associated molecular patterns, and damage-associated molecular patterns, ie RNA fragments of damaged or dying cells. Their stimulation creates an immune response. Within the scope of this work, the effect of the stimulation of TLR 7 and TLR 8 expressing PANC-1 cells with regard to growth behavior and chemosensitivity to 5-FU was investigated. That this effect was dependent on the expression of TLR7 and TLR8 could be proven by the fact that PANC-1 cells without the expression of TLR7 or TLR8 as well as TLR7- or TLR8-expressing PANC-1 cells by means of siRNA knockdown for TLR7 or TLR8 did not showed increased growth. The chemosensitivity to 5-FU in an LD50 dose was significantly reduced in the stimulated PANC-1 cells compared to the unstimulated cells. At the molecular level, there was a trend towards an increase in apoptosis-inhibiting, growth-promoting and inflammation-maintaining factors (IL-6, NF-kB, COX-2). In summary, it could be shown that the stimulation of toll-like receptors 7 and 8 expressing pancreatic carcinoma cells can be associated with further tumor growth and reduced chemosensitivity and the resulting poor therapeutic response.

Simulation modeling is the most cost-effective way of studying real life transportation problems, either existing or anticipated, without disturbing the balance of the transportation system. There is a vast suite of simulation models available in market, ready to choose from macroscopic, mesoscopic, or microscopic in nature, to study different transportation system elements like freeways, highways, signalized and un-signalized intersections. However, most of these network simulation models, like PARAMICS, VISSIM, CORSIM … etc, do not come readily available with built in toll plaza models. On the other hand, many researchers have independently developed toll plaza models, which can only model an isolated toll plaza without the road network. These toll plaza models, which are based on queuing theory (and some are macroscopic in nature), do not take into account headway, gap acceptance, or inter-vehicle interaction to follow a lead car or to perform lane changing maneuvers. Vehicles just upstream of the toll plaza are assigned to one of the toll lanes, solely based on the payment method (manual, automatic coin machine, or electronic toll collection) and queue lengths at the toll lanes. For instance, if a vehicle is traveling in the leftmost lane and the rightmost toll lane has the shortest queue length, then the queuing model will assign this vehicle to the rightmost lane, and the vehicle will do unrealistic maneuvering to reach to the assigned toll lane instantly. Microscopic network simulation models simulate the vehicular movements based on lane-changing and car-following rules. If such a model could be customized to serve the purpose of the toll plaza simulation, it will simulate the vehicular movements just upstream and downstream of the toll plaza more realistically. Being a network simulation model, it can also model the road network integrated with the plaza, which can be used to study the entire toll road corridor, unlike the isolated toll plaza models. In addition to being a microscopic network simulation model, PARAMICS has many simulation tools, which can be customized to develop a network model with enhanced toll plaza simulation capabilities. PARAMICS also provides the flexibility of using an aerial picture of the toll plaza and upstream/downstream sections of the road as overlay, to ensure that the toll plaza model operates under similar geometric conditions as the real plaza. Using an overlay, exact details of the transition area can be fed into the model. In real life, there is a smooth transition (in terms of the number of lanes and the width of the roadway) from the uniform free-flowing section of the roadway to the toll plaza. Detailed representation of the transition area, in terms of geometry and curb of the roadway along with the number of lanes, is essential for a realistic toll plaza simulation. This kind of detail is not available in a queuing model. As the roadway approaches the toll plaza, it contains more lanes compared to its upstream segments. However, in a simulation model vehicles have a tendency to maintain the same old lanes, and the newly added lanes remain unoccupied by the vehicles. Next-lane Allocation feature in PARAMICS can be used to map upstream lanes onto downstream lanes, preventing this unrealistic behavior from occurring in the simulation model. It tells the vehicles in a particular upstream lane to choose from one or more of the downstream lanes as per the settings. Next-lane allocation can be used in such a manner that all the downstream lanes are utilized. PARAMICS has several other tools such as Restrictions Manager, Vehicle Type Manager, Lane-choices Rules, HOV Lanes, and Vehicle Actuated (VA) Signals which can be used in combination to build a toll plaza model. A microscopic 'Holland East Plaza - SR408' network model has been developed using PARAMICS V5.1. This model contains the plaza and the downstream section of SR 408 Westbound till I-4 interchange in downtown Orlando. This model has been successfully calibrated and validated for the mainline toll plaza and ramp volumes for year 2004. Several hypothetical incident scenarios were simulated to study an entire corridor from the toll plaza to Interstate 4. It was found that the volumes on I-4 off-ramp and SR 408 mainline were affected the most under incident conditions. Volumes for other ramps were not affected in the same proportions. An incident on mainline toll road affected the throughput of the plaza significantly, but the same is not true for an incident on an off-ramp. Travel times to I-4 off-ramps and SR 408 thru lanes were the most sensitive in each of the incident scenarios. In case of the elimination of tolls during the hurricane evacuation, the throughput of the plaza increased significantly. Travel times for the vehicles coming through the plaza and going to different destinations decreased significantly, while it increased for vehicles using on-ramps, because of their inability to merge in the mainline traffic due to the increased toll road volume. The developed model in this thesis has the potential of transportation network wide applications with multiple toll plazas.

The Immune system exerts its response against invading pathogens via a cumulative, sequential cooperation of immune cells coordinated by their secreted products. Immune cells, such as macrophages and dendritic cells (DCs), express toll-like receptors (TLRs) to sense the presence of pathogens through pathogen-associated molecular patterns (PAMPs). The interaction of PAMPs with TLRs elicits a cytosolic signaling cascade that enhances the expression of genes to stimulate inflammation. Interleukin 1 receptor-associated kinase 2 (IRAK2) is a component of the TLR signaling pathway. IRAK2 transduces the TLR signal via a direct interaction with TNF receptor-associated factor 6 (TRAF6) and subsequent enhancement of its ubiquitination. During my PhD thesis, I determined that a 55-amino acid long stretch at the C-terminal end of IRAK2 is important for TLR signaling. Overexpression of C-terminal truncated IRAK2 (IRAK2Δ55) in the murine macrophage cell line RAW 264.7 led to impaired CD40 expression after TLR4 stimulation by Lipopolysaccharide (LPS). I observed attenuated competency of IRAK2Δ55 in restoring a full TLR signaling response i.e. IL-6 secretion, NO production and CD40 expression in IRAK2-deficient RAW cells generated via CRISPR-Cas9 approach. Additionally, diminished TLR4 induced activation of nuclear factor κB (NF-κB) and extracellular signal related kinase (ERK) was observed with IRAK2Δ55 reconstituted RAW cells as compared to cell reconstituted with wildtype IRAK2. IRAK2Δ55 reconstituted RAW cells also exhibited reduced TLR4-induced cell death and phosphorylation of receptor interacting protein kinase 3 (RIP3). Co-immunoprecipitation experiments in HEK 293T cells showed that IRAK2Δ55 was still able to bind to TRAF6 alike IRAK2 but failed to induce ubiquitination of TRAF6. In conclusion, the results suggest that the IRAK2 TRAF6 interaction is not sufficient to sustain full TLR signaling. An C-terminus-dependent unknown molecular mechanism is also involved. Through my PhD work, I also analyzed a B cell lineage-specific HECTD1 knock-out mice. HECTD1 is an E3 ubiquitin ligase for various substrate proteins, such as heat shock protein 90 (HSP90), adenomatous polyposis coli and phosphatidylinositol phosphate kinase type 1 γ. Hsp90 regulates a variety of signaling molecules in NF-κB activation pathways which are essential for an optimal B cell response. HECTD1-deficient pro-B cells developed normally into mature B cells. However, TLR4 stimulated HECTD1-deficient B cells displayed reduced immunoglobulin (Ig) production in in vitro cultures. In addition, mice with HECTD1-deficient B cells showed a diminished Ig response after nitrophenylacetyl-keyhole limpet hemocyanin immunization. Thus, HECTD1 is necessary for efficient Ig secretion. / Auf das Eindringen von Pathogenen in den Körper antwortet das Immunsystem mit einer kumulativen, sequenziellen und wechselseitigen Zusammenarbeit zwischen Immunzellen, ihren Oberflächenrezeptoren sowie den von ihnen sezernierten Mediatoren. Immunzellen, wie Makrophagen und dendritische Zellen (DZ), sind dabei in der Lage mittels Toll-like Rezeptoren (TLRs) das Vorhandensein von Pathogenen über Pathogen-assoziierte molekulare Muster (pathogen-associated molecular patterns, PAMPs) zu detektieren. Die Bindung von PAMPs an TLRs führt über intrazelluläre Signalkaskaden zu einer verstärkten Expression pro-inflammatorischer Gene und damit zur Initiierung einer Immunreaktion. Die Interleukin 1 Rezeptor-assoziierte Kinase 2 (IRAK2) ist einer Komponente der TLR Signalkaskade. IRAK2 bindet direkt an den TNF-Rezeptor-assozierten Faktor 6 (TRAF6), welcher daraufhin verstärkt ubiquitiniert wird. In meiner Promotionsarbeit habe ich einen 55 Aminosäure langen Abschnitt im C-Terminus von IRAK2 identifiziert, der für die Signalleitung von TLRs essentiell ist. Die Überexpression von mutierten IRAK2, dem dieser C-terminale Bereich fehlt (IRAK2∆55), in der murinen Macrophagen Zelllinie RAW 264.7 führte zu einer verminderten Expression von CD40 nach Stimulation des TLR4 durch Lipopolysaccharid (LPS). Wurden IRAK2-defiziente RAW Zellen mit dem mutierten IRAK2∆55 Gen rekonstituiert, zeigten diese Zellen verglichen mit Zellen, die mit dem wildtypischen Gen rekonstituiert wurden, eine verminderte Aktivierung des nuclear factor κB (NF-κB) und der extracellular signal related kinase (ERK) nach Stimulation des TLR4. Ebenso waren die Expression von CD40, die Sekretion von IL-6 und NO gestört. In IRAK2-defizienten und IRAK2∆55 RAW Zellen war eine Reduktion des durch TLR4 induzierten Zelltodes sowie der TLR4-induzierten Phosphorylierung der Rezeptor-interagierenden Proteinkinase 3 (RIP3) zu beobachten. Ko-Immunpräzipitationsexperimente mit HEK 293T Zellen zeigten, dass IRAK2∆55 genauso wie intaktes IRAK2 zwar in der Lage ist, TRAF6 zu binden, aber nicht dessen Ubiquitinylierung zu induzieren. Die Ergebnisse dieser Arbeit zeigen, dass die Interaktion von IRAK2 mit TRAF6 für ein optimales TLR-Signal nicht ausreichend ist und deshalb ein bisher unbekannter Mechanismus an der Signalweiterleitung beteiligt sein muss. Dieser Mechanismus ist vom C-terminalen Ende von IRAK2 abhängig. In einem zweiten Teil meiner Doktorarbeit analysierte ich B-Zellen von Mäusen, in denen HECTD1-spezifisch in der B-Zellentwicklungslinie deletiert wurde. HECTD1 ist eine E3 Ubiquitin-Ligase für zahlreiche Substratproteine, wie bspw. dem Hitzeschock-Protein (heat-shock-protein, HSP90), dem adenomatösen Polyposis coli Protein oder der Phosphatidylinositol Phosphatkinase Typ 1 γ. HSP90 reguliert eine Vielzahl an Signalmolekülen im NF-κB Signalweg, die für eine optimale B-Zell-Antwort wesentlich sind. HECTD1-defiziente pro-B-Zellen entwickelten sich normal zu reifen B-Zellen. Die Stimulation des TLR4 auf HECTD1-defizienten B-Zellen führte in vitro zu einer im Vergleich zu wildtypischen B-Zellen reduzierten Immunglobulin-Sekretion. Eine reduzierte Immunglobulin-Antwort konnte auch in B-Zell-spezifischen hectd1-/- Mäusen beobachtet werden, wenn diese zuvor mit Schlitzschnecken-Hämocyanin (Keyhole Limpet Hemocyanin, NP-KLH) immunisiert wurden. Die reduzierte Produktion von Antikörpern durch HECTD1-defiziente B-Zellen zeigt, dass dieses Protein für diese zentrale Aufgabe von B-Zellen notwendig ist.

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The charging systems presently being used in toll facilities impose discomfort and inconvenience to patrons, in terms of delay and stops. This report presents an analytical method to estimate delay and stops in toll plazas. These variables are then utilized to evaluate user costs and toxic gases emitted in toll plazas. A large amount of information on highway user costs was collected and synthesized to be incorporated in this economic evaluation. Recommendations on the amount of toll that should be charged to take into account user costs induced by toll plazas are given in this report. / Master of Science

Yes / Alopecia areata (AA) is thought to be an autoimmune process. In other autoimmune diseases, the innate immune system and Toll‐like receptors (TLRs) can play a significant role. Expression of TLR7, TLR9 and associated inducible genes was evaluated by quantitative PCR in peripheral blood mononuclear cells (PBMCs) from 10 healthy individuals and 19 AA patients, categorized according to disease duration, activity and hair loss extent. Microdissected scalp biopsies from five patients and four controls were also assessed by quantitative PCR and immunohistology. TLR9 was significantly upregulated 2.37 fold in AA PBMCs. Notably, TLR9 was most significantly upregulated in patients with active AA, as shown by a positive hair pull test, compared to stable AA patients. In hair follicle bulbs from AA patients, IFNG and TLR7 exhibited statistically significant 3.85 and 2.70 fold increases in mRNA, respectively. Immunohistology revealed TLR7 present in lesional follicles, while TLR9 positive cells were primarily observed peri‐bulbar to AA affected hair follicles. The increased expression of TLR7 and TLR9 suggest components of the innate immune system may be active in AA pathogenesis. / National Alopecia Areata Foundation; Canadian Dermatology Foundation; Michael Smith Foundation for Health Research, Grant/Award Number: CI‐SCH‐00480(06‐1); Canadian Institutes of Health Research, Grant/Award Number: MOP‐167368 and MSH‐192593‐140450

Thesis (MDF) -- Stellenbosch University, 2011. / ENGLISH ABSTRACT: The aim of this research report is to analyse the feasibility of Open Road Tolling (ORT) and its development in South Africa through the Gauteng Freeway Improvement Project (GFIP). ORT represents the next generation of Electronic Toll Collection (ETC) and this research report will assess to what extent the GFIP scheme is in line with other comparable tolling schemes; and is the institutional environment amenable to ORT. This will allow one to gauge the feasibility of the scheme and its potential for acceptability and success. The research report outlines the number of risks that come with an ORT scheme and these include amongst others collection risk, enforcement, technology, privacy and public acceptance. The success of the GFIP will largely be determined by how well these risks are mitigated and how the benefits can be marketed to the users. The literature review illustrates that whether road pricing schemes have failed to move forward, have been implemented, are currently under development, or still in the planning stage as a concept there are several consistent lessons and critical success factors one should apply when structuring a scheme. In the discussions with stakeholders, the following conclusions with regards to the feasibility of ORT and its development in South Africa were as follows: - The factors which need to be addressed include political risk, effective marketing of the scheme to the public, obtaining political will and support, building trust between the scheme developer and the user, managing perceptions and acknowledgement of the fact that the scheme will need to prove itself over time. - Inadequate demonstration - Incorporating interoperability yields benefits in terms in terms of network externalities, the ability to use a single transponder for multiple tolling plazas and points, along with the potential for alternative uses for the transponder. - ORT as a viable solution for the GFIP is feasible from a technical point in that it’s the only way in which one can collect tolls from a high volume network and not cause disruptions in the flow of traffic. However, there are a number of persistent residual risks that SANRAL cannot entirely mitigate and some fall under the realm of political risk. - While SANRAL has applied best practice principles in structuring the GFIP with the aim of providing value for money for the user and as far as possible tackling the issue of affordability, there are certain realities, such as the recent global financial crisis, the infrastructure backlog of the country, users paying for roads which were free and challenges with overall service delivery which place a strain on the legitimacy of the GFIP ORT scheme.

Mesenchymal stem cells (MSCs) represent a heterogeneous population of stromal cells with a pluripotent differentiation potential. They can be isolated from multiple tissues of mesodermal origin, such as bone marrow, adipose tissue, umbilical cord blood and peripheral blood and afterwards externally expanded according their adherence to the plastic surfaces. These cells show remarkable immunomodulatory properties, suppressing T-, B- and NK-cell functions, and also modulating dendritic cell activities and influencing immune responses during tissue repair and recovery. MSCs have been shown to possess ability to migrate to sites of inflammation and tissue injury. All these properties make MSCs a promising tool for clinical application. Our primary goal was to identify processes that may influence immunoregulatory effects of MSCs. In order to promote immunossupressive qualities of MSCs we established the scheme comprising MSCs precultivated with various cytokines and Toll-like receptors (TLR) ligands in vitro, with the final aim to improve the therapeutic effect of MSCs on wound healing in vivo. We studied modulation of MSCs properties and consequently the effect of influenced MSCs on cells of the immune system. The immunosuppression is mainly mediated through secreted factors that MSCs produced after...

8 Abstract Introduction: Celiac disease is indentified as the loss of oral tolerance to gluten, it is an organ-specific autoimmune disease in which both, adaptive and innate immunity participate. Monocytes are important part of immune system; they have many functions and express very diverse membrane receptors including Toll-like receptors (TLRs). TLRs are involved in the innate immune response, specifically TLR2 and TLR4 are crucial for recognition of bacterial components and TLR7 recognizes virus's ssRNA. Monocytes also produce prolaktin (PRL), which acts as a cytokine that modulates immune responses. To clarify the role of innate immunity and circulating monocytes in pathogenesis of celiac disease, we focused on changes in expression of selected Toll-like receptors (TLR2, TLR4, TLR7), prolactin, some pro- a anti-inflammatory cytokines (TNF-α, IL-6, IL-12, IL-10). We monitored the influence of the SNP - 1149 G/T on the expression of PRL mRNA. Another objective of this work was the introduction and optimization of in vitro methods for cultivation and stimulation of peripheral monocytes. Material and Methods: This pilot study includes 21 patients with celiac disease and 40 healthy controls. For determination of mRNA levels of the studied genes we isolated RNA from monocytes that were isolated by...