Interactions between endocarditis-derived Streptococcus gallolyticus subsp. gallolyticus isolates and human endothelial cells

<p>Abstract</p> <p>Background</p> <p><it>Streptococcus gallolyticus </it>subsp. <it>gallolyticus </it>is an important causative agent of infective endocarditis (IE) but the knowledge on virulence factors is limited and the pathogenesis of the infection is poorly understood. In the present study, we established an experimental <it>in vitro </it>IE cell culture model using EA.hy926 and HUVEC cells to investigate the adhesion and invasion characteristics of 23 <it>Streptococcus gallolyticus </it>subsp. <it>gallolyticus </it>strains from different origins (human IE-derived isolates, other human clinical isolates, animal isolates). Adhesion to eight components of the extracellular matrix (ECM) and the ability to form biofilms <it>in vitro </it>was examined in order to reveal features of <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>endothelial infection. In addition, the strains were analyzed for the presence of the three virulence factors <it>gtf</it>, <it>pilB</it>, and <it>fimB </it>by PCR.</p> <p>Results</p> <p>The adherence to and invasion characteristics of the examined <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>strains to the endothelial cell line EA.hy926 differ significantly among themselves. In contrast, the usage of three different <it>in vitro </it>models (EA.hy926 cells, primary endothelial cells (HUVECs), mechanical stretched cells) revealed no differences regarding the adherence to and invasion characteristics of different strains. Adherence to the ECM proteins collagen I, II and IV revealed the highest values, followed by fibrinogen, tenascin and laminin. Moreover, a strong correlation was observed in binding to these proteins by the analyzed strains. All strains show the capability to adhere to polystyrole surfaces and form biofilms. We further confirmed the presence of the genes of two known virulence factors (<it>fimB</it>: all strains, <it>gtf</it>: 19 of 23 strains) and demonstrated the presence of the gene of one new putative virulence factor (<it>pilB</it>: 9 of 23 strains) by PCR.</p> <p>Conclusion</p> <p>Our study provides the first description of <it>S. gallolyticus </it>subsp. <it>gallolyticus </it>adhesion and invasion of human endothelial cells, revealing important initial information of strain variability, behaviour and characteristics of this as yet barely analyzed pathogen.</p

Utrophin Up-Regulation by an Artificial Transcription Factor in Transgenic Mice

Duchenne Muscular Dystrophy (DMD) is a severe muscle degenerative disease, due to absence of dystrophin. There is currently no effective treatment for DMD. Our aim is to up-regulate the expression level of the dystrophin related gene utrophin in DMD, complementing in this way the lack of dystrophin functions. To this end we designed and engineered several synthetic zinc finger based transcription factors. In particular, we have previously shown that the artificial three zinc finger protein named Jazz, fused with the appropriate effector domain, is able to drive the transcription of a test gene from the utrophin promoter “A”. Here we report on the characterization of Vp16-Jazz-transgenic mice that specifically over-express the utrophin gene at the muscular level. A Chromatin Immunoprecipitation assay (ChIP) demonstrated the effective access/binding of the Jazz protein to active chromatin in mouse muscle and Vp16-Jazz was shown to be able to up-regulate endogenous utrophin gene expression by immunohistochemistry, western blot analyses and real-time PCR. To our knowledge, this is the first example of a transgenic mouse expressing an artificial gene coding for a zinc finger based transcription factor. The achievement of Vp16-Jazz transgenic mice validates the strategy of transcriptional targeting of endogenous genes and could represent an exclusive animal model for use in drug discovery and therapeutics

Transition Technologies for Electrification and Optimisation of Bus Transport Systems

The topical issue of climate change has increasingly become important as scenarios indicate an increase of 2.5–7.8°C in the global mean temperature by the end of this century, if no greenhouse gas emissions are reduced. The transport sector depends strongly on fossil fuels and has been therefore considered as one key sector concerning climate change mitigation. In this regard, a key role is played by cities, since progressing urbanisation will presumably lead to a higher demand for urban transport. This doctoral thesis addresses the transition phase of public bus transport systems by exploring electrification as a vector for decarbonisation. The C40-city of Curitiba in Southern Brazil is used as a case study. The research is of explorative and empirical nature. Quantitative research methods are applied to compare bus technologies as well as new optimisation models and planning tools are developed to support data analytics and research in the areas of simulation, optimisation and (long-term) planning of energy and transport systems at different levels of consideration. The results from the comparison of different buses show large potentials to save energy and reduce emissions during the operation phase, for example, when using hybrid-electric or plug-in hybrid-electric buses instead of conventional buses. Moreover, energy savings in the operation phase also imply avoidance of fuel production and supply. Additionally, electrified buses can also reduce operational uncertainty caused by varying driving cycles and fluctuating fuel prices concerning an absolute variation of both energy use and fuel cost in the operation phase. A real-time optimisation model was developed, and its concept tested to estimate potentials for energy savings and all-electric operation from the operational optimisation of a plug-in hybrid-electric bus fleet. Different management strategies were simulated concerning the charging schedule and all-electric operation of the bus fleet. While energy savings can be significantly increased through a structural change towards more electrified buses, a large potential to increase the total all-electric operation of the bus fleet was estimated through operational optimisation. Consequently, both a structural change and operational optimisation should be jointly applied to maximise the benefits gained from electrification in a bus transport system. The software system OSeMOSYS-PuLP was developed for empirical deterministic-stochastic modelling based on the OSeMOSYS modelling framework, which enables the use of a Monte Carlo simulation. The open source design of the tool shall enhance transparency and trustworthiness in studies. It is transferable to many cases and makes it possible for analysts and researchers to generate new sets of conclusions together with associated probability distributions considering the use of real-world datasets, e.g. from open data initiatives as the one in Curitiba. In summary, the research findings, applied methods and developed tools can be used to support and inform analysts and decision-makers in the area of transport and energy systems planning in data-driven decision-making processes to develop and assess different technological options and strategies at different levels while considering associated uncertainties.Den aktuella frågan om klimatförändringar har blivit allt viktigare eftersom scenarier indikerar en ökning med 2,5–7,8°C i den globala medeltemperaturen i slutet av detta århundrade, om inga utsläpp av växthusgaser minskar. Transportsektorn är starkt beroende av fossila bränslen och har därför betraktats som en nyckelsektor när det gäller att minska klimatförändringarna. I detta avseende spelar städer en nyckelroll, eftersom en framtida urbanisering förmodligen kommer att leda till en ökad efterfrågan på stadstrafik. Denna doktorsavhandling behandlar övergångsfasen för kollektivtrafiksystem genom att utforska elektrifiering som en vektor för koldioxidminskning. C40-staden Curitiba i södra Brasilien används som fallstudie. Forskningen är av utforskande och empirisk karaktär. Kvantitativa forskningsmetoder används för att jämföra bussteknologier samt nya optimeringsmodeller och planeringsverktyg utvecklas för att stödja dataanalys och forskning inom områdena simulering, optimering och (långsiktig) planering av energi- och transportsystem på olika nivåer av övervägande. Resultaten från jämförelsen av olika bussar visar stora möjligheter att spara energi och minska utsläppen under driftsfasen, till exempel när man använder hybrid-elektriska eller laddhybrid-elektriska bussar istället för konventionella bussar. Dessutom innebär energibesparingar i driftsfasen också undvikande av bränsleproduktion och -försörjning. Dessutom kan elektrifierade bussar också minska driftosäkerheten orsakad av varierande körcykler och fluktuerande bränslepriser beträffande en variation av både energianvändning och bränslekostnader i driftsfasen. En realtidsoptimeringsmodell utvecklades och dess koncept testades för att uppskatta potentialen för energibesparingar och helelektrisk drift från driftsoptimering av en laddhybrid-elektrisk bussflotta. Olika förvaltningsstrategier simulerades beträffande laddningsschemat och elektrisk drift av bussflottan. Medan energibesparingar kan ökas betydligt genom en strukturell förändring mot mer elektrifierade bussar, uppskattades en stor potential för att öka den totala elektriska driften av bussflottan genom driftsoptimering. Följaktligen bör både en strukturell förändring och driftsoptimering tillämpas gemensamt för att maximera fördelarna från elektrifiering i ett busstransportsystem. Programvarusystemet OSeMOSYS-PuLP utvecklades för empirisk deterministisk-stokastisk modellering baserat på OSeMOSYS-modelleringsramverket, vilket möjliggör användning av en Monte Carlo simulering. Den öppna källkods-designen av verktyget ska öka insynen och pålitligheten i studier. Det kan överföras till många fall och gör det möjligt för analytiker och forskare att generera nya slutsatser tillsammans med tillhörande sannolikhetsfördelningar med tanke på användningen av verklig data, t.ex. från öppna datainitiativ som i Curitiba. Sammanfattningsvis kan forskningsresultaten, tillämpade metoder och utvecklade verktyg användas för att stödja och informera analytiker och beslutsfattare inom området transport och energisystemplanering i datadrivna beslutsprocesser för att utveckla och utvärdera olika tekniska alternativ och strategier på olika nivåer med hänsyn till tillhörande osäkerheter

Assessing the potential of fuel saving and emissions reduction of the bus rapid transit system in Curitiba, Brazil

The transport sector contributes significantly to global energy use and emissions due to its traditional dependency on fossil fuels. Climate change, security of energy supply and increasing mobility demand is mobilising governments around the challenges of sustainable transport. Immediate opportunities to reduce emissions exist through the adoption of new bus technologies, e.g. advanced powertrains. This thesis analysed energy use and carbon dioxide (CO2) emissions of conventional, hybrid-electric, and plug-in hybrid-electric city buses including two-axle, articulated, and biarticulated chassis types (A total of 6 bus types) for the operation phase (Tank-to-Wheel) in Curitiba, Brazil. The systems analysis tool – Advanced Vehicle Simulator (ADVISOR) and a carbon balance method were applied. Seven bus routes and six operation times for each (i.e. 42 driving cycles) are considered based on real-world data. The results show that hybrid-electric and plug-in hybrid-electric two-axle city buses consume 30% and 58% less energy per distance (MJ/km) compared to a conventional two-axle city bus (i.e. 17.46 MJ/km). Additionally, the energy use per passenger-distance (MJ/pkm) of a conventional biarticulated city bus amounts to 0.22 MJ/pkm, which is 41% and 24% lower compared to conventional and hybrid-electric two-axle city buses, respectively. This is mainly due to the former’s large passenger carrying capacity. Large passenger carrying capacities can reduce energy use (MJ/pkm) if the occupancy rate of the city bus is sufficient high. Bus routes with fewer stops decrease energy use by 10-26% depending on the city bus, because of reductions in losses from acceleration and braking. The CO2 emissions are linearly proportional to the estimated energy use following from the carbon balance method, e.g. CO2 emissions for a conventional two-axle city bus amount to 1299 g/km. Further results show that energy use of city bus operation depends on the operation time due to different traffic conditions and driving cycle characteristics. An additional analysis shows that energy use estimations can vary strongly between considered driving cycles from real-world data. The study concludes that advanced powertrains with electric drive capabilities, large passenger carrying capacities and bus routes with a fewer number of bus stops are beneficial in terms of reducing energy use and CO2 emissions of city bus operation in Curitiba

OSeMOSYS-PuLP: A Stochastic Modeling Framework for Long-Term Energy Systems Modeling

Recent open-data movements give access to large datasets derived from real-world observations. This data can be utilized to enhance energy systems modeling in terms of heterogeneity, confidence, and transparency. Furthermore, it allows to shift away from the common practice of considering average values towards probability distributions. In turn, heterogeneity and randomness of the real-world can be captured that are usually found in large samples of real-world data. This paper presents a methodological framework for an empirical deterministic&#8211;stochastic modeling approach to utilize large real-world datasets in long-term energy systems modeling. A new software system&#8212;OSeMOSYS-PuLP&#8212;was developed and is available now.It adds the feature of Monte Carlo simulations to the existing open-source energy modeling system (the OSeMOSYS modeling framework). An application example is given, in which the initial application example of OSeMOSYS is used and modified to include real-world operation data from a public bus transport system

Smart City Concepts in Curitiba - innovation for sustainable mobility and energy efficiency: Project NEWSLETTER, November 2016

QC 20170201Smart city concepts in Curitiba – innovation for sustainable mobility and energy efficienc

Smart City Concepts in Curitiba - innovation for sustainable mobility and energy efficiency: Project NEWSLETTER, November 2016

QC 20170201Smart city concepts in Curitiba – innovation for sustainable mobility and energy efficienc

Smart City Concepts in Curitiba - innovation for sustainable mobility and energy efficiency : Project NEWSLETTER, January 2016

QC 20160524</p