Antimykotika modulieren die Produktion proinflammatorischer Zytokine und das Phagozytose-Verhalten humaner Monozyten in einem <em>In-vitro</em>-Sepsis-Modell

Bei der Sepsis stellen neben bakteriellen Erregern zunehmend auch Pilzerreger eine große Gefahr für die Patienten dar, häufig im Rahmen einer sekundären Superinfektion oder einer reinen Pilzsepsis. So erweitert sich auch das antimikrobielle Spektrum der Pharmaka um den Einsatz von Antimykotika. Zu dieser Substanzgruppe ist zurzeit nur sehr wenig über potentielle Interaktionen mit der angeborenen Immunität bekannt. In dieser Arbeit sollte geklärt werden, ob drei im klinischen Alltag häufig verwendete Antimykotika unterschiedlicher Substanzklassen in der Lage sind, in Lipopolysaccharid(LPS)-stimulierten und unstimulierten THP-1-Monozyten die Expression und Sekretion der proinflammatorischen Zytokine IL-1β, IL-6 und TNF-α über den zeitlichen Verlauf von 2 h, 6 h und 24 h zu regulieren. Zudem wurde der Effekt der drei Substanzen auf die Phagozytoserate der Zellen im zeitlichen Verlauf untersucht. In Anwesenheit von LPS war das liposomale Amphotericin-B (L-AMB) als hauptsächlich antiinflammatorisch wirkende Substanz zu identifizieren. Es reduzierte die Sekretion aller drei Zytokine verglichen mit LPS-Kontrollen. Größtenteils erfuhren auch die entsprechenden mRNA-Levels von TNF-α, IL-1β und IL-6 eine Down-Regulation durch die Ko-Inkubation mit LPS und L-AMB im Langzeitverlauf. Itraconazol (ITC) dagegen zeigte unter Sepsisbedingungen eindeutig proinflammatorisches Potential, indem es die Ausschüttung von IL-1β und TNF-α signifikant steigerte. Auch auf Genexpressionsebene war hier ein signifikanter Anstieg der mRNA aller drei Zytokine zu den meisten Messzeitpunkten zu beobachten. Anidulafungin (ANI) vermochte auf Genexpressionsebene die drei Zytokine differentiell zu regulieren, während im Zellüberstand lediglich TNF-α erhöht messbar war. Die Substanzen hatten in Monoinkubation unterschiedliche Einflüsse auf die Zytokin-mRNA-Produktion, jedoch ohne konsekutiven Einfluss auf die Proteinausschüttung. Hier zeigten sich keine Unterschiede gegenüber den unstimulierten Kontrollen. Auf das Phagozytoseverhalten hatten vor allem L-AMB und ITC einen Einfluss. Beide Substanzen reduzierten die Phagozytoseaktivität in LPS-stimulierten Monozyten. Es konnte in dieser Arbeit gezeigt werden, dass drei strukturell nicht miteinander verwandte Antimykotika in mit LPS stimulierten humanen Monozyten einen differentiellen Einfluss auf die Expression von proinflammatorischen Zytokinen und auch auf deren Sekretion ausüben. Ein Einfluss auf das Phagozytoseverhalten konnte ebenfalls nachgewiesen werden. Bestätigen sich die unter In-vitro-Bedingungen erzielten Ergebnisse auch in weiterführenden In-vivo-Studien, besteht die Möglichkeit, durch Ausnutzung der immunmodulatorischen Eigenschaften der Antimykotika, das Muster der Immunantwort bei septischen Patienten zu steuern und auf diese Weise die Mortalitätsrate beeinflussen zu können

h-Adaptive finite element method: extension of the isotropic error density recovery remeshing strategy of quadratic order

Orientador: Prof. Dr. Jucélio Tomás PereiraDissertação (mestrado) - Universidade Federal do Paraná, Setor de Tecnologia, Programa de Pós-Graduação em Engenharia Mecânica. Defesa : Curitiba, 05/07/2018Inclui referências: p.86-90Área de concentração: Mecânica dos Sólidos e VibraçõesResumo: O Método de Elementos Finitos (MEF) é uma técnica para resolver numericamente problemas físicos comumente utilizada na engenheria. Um fator importante na obtenção de uma solução precisa e eficiente decorre da utilização adequada da malha de discretização. Tipicamente, técnicas h-adaptativas são empregadas para projeção de uma malha ótima, onde o erro estimado em cada elemento é distribuído e minimizado de acordo com um critério de malha ótima. Neste contexto, o presente trabalho estende e avalia o método de refino hadaptativo denominado de Recuperação da Densidade do Erro Isotrópica (IEDR) para elementos triangulares quadráticos. Inicialmente desenvolvida para elementos lineares, esta técnica baseia-se na recuperação de uma função densidade do erro em energia em conjunto com a solução de um problema de otimização que busca o tamanho do novo elemento. Dessa maneira, a metodologia IEDR aborda os erros provenientes do MEF de maneira que contenha informações locais com maior abrangência, já que, nesta metodologia, uma função densidade do erro é recuperada. Os parâmetros de qualidade de malha, obtidos através desta técnica, são comparados à tradicionais técnicas de projeto de malha denominada de Chp e à técnica Li- Bettess (LB). A estimativa dos erros de discretização é realizada através do estimador de erro a posteriori baseado em recuperação, onde os gradientes recuperados são obtidos pelo método Superconvergente de Recuperação de Padrões (Superconvergent Patch Recovery - SPR). A implementação computacional é elaborada no software Matlab®, sendo a geração de malha realizada pelo gerador Bidimensional Anisotropic Mesh Generator (BAMG). Resultados numéricos demonstram que o processo h-adaptativo baseado na técnica IEDR obtém malhas convergentes para problemas com e sem singularidade, as quais apresentam, em geral, vantagens em relação ao número de graus de liberdade, à convergência e aos parâmetros de malha em comparação à tradicional técnica Chp e vantagens comparada à técnica LB para elementos quadráticos. Palavras-chave: Elemento Triangular de Deformações Lineares. h-adaptividade. Método dos Elementos Finitos. Estimadores de erro a posteriori. Recuperação da Densidade do Erro Isotrópica.Abstract: The finite element method (FEM) is a technique used to numerically solve physics problems which is often used in engineering. One factor in obtaining a solution that has acceptable accuracy is using adequate mesh discretization. Typically, h-adaptive techniques are used to determine new element sizes based on errors distributed among each element following an optimum mesh criterion. In this context, the current work proposes to extend and analyze the Isotropic Error Density Recovery (IEDR) h-refinement method for quadratic triangular finite elements. Initially developed for linear triangular finite elements, the extended technique is based on the recovery of an error density function, such that an optimization technique is used to search for the new element sizes. Hence, the IEDR technique utilizes more information of the local errors to design element sizes due to the recovery of an element error density function. The h-adaptive finite element method process based on the IEDR technique is compared to the traditionally used Chp and Li-Bettess mesh design techniques found in the literature. The discretization error estimates are achieved via a recovery based a posteriori error estimator, whereas the recovered gradients are obtained using the Superconvergent Patch Recovery Method. The algorithm is implemented using Matlab®, while the mesh generation is done by the Bidimensional Anisotropic Mesh Generator (BAMG). Results show, overall, that the meshes designed through the proposed methodology obtain superior mesh quality parameters, less degrees of freedom and better convergence in comparison with the traditional Chp remeshing methodology and advantages compared to the Li-Bettess element size estimation technique for quadratic elements. Keywords: Linear Strain Triangle. h-adaptativity. Finite Element Method. a posteriori Error Estimates. Isotropic Error Density Recovery

Characteristics, distribution and morphogenesis of subtidal microbial systems in Shark Bay, Australia

The distribution, nature and extent of microbial deposits in Hamelin Pool, Shark Bay have been investigated and mapped with emphasis on the occurrence, external morphologies, internal fabrics, constructional mechanisms, microbial communities, growth rates and sediment associations in the intertidal and previously little researched subtidal zone. Detailed georeferenced substrate mapping revealed extensive subtidal microbial deposits occupying approximately 300 km2 of the total Holocene 1400 km2 area of Hamelin Pool. The Microbial Pavement covers 227 km2 of the subtidal substrate that together with columnar structures reveals a subtidal microbial habitat which occupies an area 10 times larger than the area of the intertidal deposits. Microbial carbonate is composed of aragonite (80–98%) that reveals high positive values of δ13C (+4.46 to +5.88) and δ18O (+3.06 to +3.88) as a characteristic of the highly evaporative environment with extensive microbial activity. Oldest dated heads are 1915 and 1680 14C years BP, and the overall system was deposited in two stages; the first between 2000 and 1200 and the last from 900 years BP to the present. Slow growth rates vary from less than 0.1 mm/year to 0.5 mm/year. Different internal fabrics were constructed according to their position in relation to the littoral zone by distinct microbial communities, and lateral fabric relations have been established.Evidence of shallowing upward fabric sequences of microbial origin reflects relative falling sea levels during the late Holocene and is likely useful in ancient environmental interpretation. A sequence of events and mechanisms are described emphasizing differences between the stromatolitic, thrombolitic and cryptomicrobial deposits in Shark Bay. The new substrate map and depositional history for this distinctive and peculiar microbial habitat establish the significance of subtidal structures and emphasize the geoscientific importance of Hamelin Pool, especially with respect to early life studies and ancient analogues for understanding microbial activity, deposit characteristics, fenestral fabrics and distribution

Microbialite response to an anthropogenic salinity gradient in Great Salt Lake, Utah.

A railroad causeway across Great Salt Lake, Utah (GSL), has restricted water flow since its construction in 1959, resulting in a more saline North Arm (NA; 24%-31% salinity) and a less saline South Arm (SA; 11%-14% salinity). Here, we characterized microbial carbonates collected from the SA and the NA to evaluate the effect of increased salinity on community composition and abundance and to determine whether the communities present in the NA are still actively precipitating carbonate or if they are remnant features from prior to causeway construction. SSU rRNA gene abundances associated with the NA microbialite were three orders of magnitude lower than those associated with the SA microbialite, indicating that the latter community is more productive. SSU rRNA gene sequencing and functional gene microarray analyses indicated that SA and NA microbialite communities are distinct. In particular, abundant sequences affiliated with photoautotrophic taxa including cyanobacteria and diatoms that may drive carbonate precipitation and thus still actively form microbialites were identified in the SA microbialite; sequences affiliated with photoautotrophic taxa were in low abundance in the NA microbialite. SA and NA microbialites comprise smooth prismatic aragonite crystals. However, the SA microbialite also contained micritic aragonite, which can be formed as a result of biological activity. Collectively, these observations suggest that NA microbialites are likely to be remnant features from prior to causeway construction and indicate a strong decrease in the ability of NA microbialite communities to actively precipitate carbonate minerals. Moreover, the results suggest a role for cyanobacteria and diatoms in carbonate precipitation and microbialite formation in the SA of GSL

Temperature-dependent macromolecular X-ray crystallography

The dynamical behaviour of crystalline macromolecules and their surrounding solvent as a function of cryo-temperature is reviewed