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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
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Temperature-driven assembly processes of Orthoptera communities: Lessons on diversity, species traits, feeding interactions, and associated faecal microorganisms from elevational gradients in Southern Germany (Berchtesgaden Alps) / Temperaturabhängige Zusammensetzungsprozesse von Heuschreckengemeinschaften: Lektionen über die Diversität, Artmerkmale, Fraßinteraktionen, und Kot-Mikroorganismen von Höhengradienten in Süddeutschland (Berchtesgadener Alpen)

König, Sebastian Thomas January 2024 (has links) (PDF)
Chapter I: Introduction Temperature is a major driver of biodiversity and abundance patterns on our planet, which becomes particularly relevant facing the entanglement of an imminent biodiversity and climate crisis. Climate shapes the composition of species assemblages either directly via abiotic filtering mechanisms or indirectly through alterations in biotic interactions. Insects - integral elements of Earth’s ecosystems - are affected by climatic variation such as warming, yet responses vary among species. While species’ traits, antagonistic biotic interactions, and even species’ microbial mutualists may determine temperature-dependent assembly processes, the lion’s share of these complex relationships remains poorly understood due to methodological constraints. Mountains, recognized as hotspots of diversity and threatened by rapidly changing climatic conditions, can serve as natural experimental settings to study the response of insect assemblages and their trophic interactions to temperature variation, instrumentalizing the high regional heterogeneity of micro- and macroclimate. With this thesis, we aim to enhance our mechanistic understanding of temperature-driven assembly processes within insect communities, exemplified by Orthoptera, that are significant herbivores in temperate mountain grassland ecosystems. Therefore, we combined field surveys of Orthoptera assemblages on grassland sites with molecular tools for foodweb reconstruction, primarily leveraging the elevational gradients offered by the complex topography within the Berchtesgaden Alpine region (Bavaria, Germany) as surrogate for temperature variation (space-for-time substitution approach). In this framework, we studied the effects of temperature variation on (1) species richness, abundance, community composition, and interspecific as well as intraspecific trait patterns, (2) ecological feeding specialisation, and (3) previously neglected links to microbial associates found in the faeces. Chapter II: Temperature-driven assembly processes Climate varies at multiple scales. Since microclimate is often overlooked, we assessed effects of local temperature deviations on species and trait compositions of insect communities along macroclimatic temperature gradients in Chapter II. Therefore, we employed joint species distribution modelling to explore how traits drive variation in the climatic niches of Orthoptera species at grassland sites characterized by contrasting micro- and macroclimatic conditions. Our findings revealed two key insights: (1) additive effects of micro- and macroclimate on the diversity, but (2) interactive effects on the abundance of several species, resulting in turnover and indicating that species possess narrower climatic niches than their elevational distributions might imply. This chapter suggests positive effects of warming on Orthoptera, but also highlights that the interplay of macro- and microclimate plays a pivotal role in structuring insect communities. Thus, it underscores the importance of considering both elements when predicting the responses of species to climate change. Additionally, this chapter revealed inter- and intraspecific effects of traits on the niches and distribution of species. Chapter III: Dietary specialisation along climatic gradients A crucial trait linked to the position of climatic niches is dietary specialisation. According to the ‘altitudinal niche-breadth hypothesis’, species of high-elevation habitats should be less specialized compared to their low-elevation counterparts. However, empirical evidence on shifts in specialization is scarce for generalist insect herbivores and existing studies often fail to control for the phylogeny and abundance of interaction partners. In Chapter III, we used a combination of field observations and amplicon sequencing to reconstruct dietary relationships between Orthoptera and plants along an extensive temperature gradient. We did not find close but flexible links between individual grasshopper and plant taxa in space. While interaction network specialisation increased with temperature, the corrected dietary specialisation pattern peaked at intermediate elevations on assemblage level. These nuanced findings demonstrate that (1) resource availability, (2) phylogenetic relationships, and (3) climate can affect empirical foodwebs intra- and interspecifically and, hence, the dietary specialisation of herbivorous insects. In this context, we discuss that the underlying mechanisms involved in shaping the specialisation of herbivore assemblages may switch along temperature clines. Chapter IV: Links between faecal microbe communities, feeding habits, and climate Since gut microbes affect the fitness and digestion of insects, studying their diversity could provide novel insights into specialisation patterns. However, their association with insect hosts that differ in feeding habits and specialisation has never been investigated along elevational climatic gradients. In Chapter IV, we utilized the dietary information gathered in Chapter III to characterize links between insects with distinct feeding behaviour and the microbial communities present in their faeces, using amplicon sequencing. Both, feeding and climate affected the bacterial communities. However, the large overlap of microbes at site level suggests that common bacteria are acquired from the shared feeding environment, such as the plants consumed by the insects. These findings emphasize the influence of a broader environmental context on the composition of insect gut microbial communities. Chapter V: Discussion & Conclusions Cumulatively, the sections of this dissertation provide support for the hypothesis that climatic conditions play a role in shaping plant–herbivore systems. The detected variation of taxonomic and functional compositions contributes to our understanding of assembly processes and resulting diversity patterns within Orthoptera communities, shedding light on the mechanisms that structure their trophic interactions in diverse climates. The combined results presented suggest that a warmer climate could foster an increase of Orthoptera species richness in Central European semi-natural grasslands, also because the weak links observed between insect herbivores and plants are unlikely to limit decoupled range shifts. However, the restructuring of Orthoptera communities in response to warmer temperatures depends on species' traits such as moisture preferences or phenology. Notably, we were able to demonstrate a crucial role of microclimate for many species, partly unravelling narrower climatic niches than their elevational ranges suggest. We found evidence that not only Orthoptera community composition, specialisation, and traits varied along elevational gradients, but even microbial communities in the faeces of Orthoptera changed, which is a novel finding. This complex restructuring and reassembly of communities, coupled with the nonlinear specialisation of trophic interactions and a high diversity of associated bacteria, emphasize our currently incomplete comprehension of how ecosystems will develop under future climatic conditions, demanding caution in making simplified predictions for biodiversity change under climate warming. Since these predictions may benefit from including biotic interactions and both, micro- and macroclimate based on our findings, conservation authorities and practitioners must not neglect improving microclimatic conditions to ensure local survival of a diverse set of threatened and demanding species. In this context, mountains can play a pivotal role for biodiversity conservation since these offer heterogeneous microclimatic conditions in proximity that can be utilized by species with distinct niches. / Kapitel I: Einleitung Die Temperatur ist eine wichtige Triebkraft hinter den Artenvielfalts- und Abundanzmustern auf unserem Planeten, was angesichts der Verflechtung der unmittelbar bevorstehenden Biodiversitäts- und Klimakrise besonders relevant ist. Das Klima strukturiert die Artenvielfalt direkt durch abiotische Filtermechanismen oder indirekt durch Veränderungen biotischer Wechselwirkungen. Insekten - wesentliche Bestandteile der Ökosysteme der Erde - sind von klimatischen Veränderungen wie der Erwärmung betroffen, reagieren aber je nach Art unterschiedlich. Während die Merkmale der Arten, antagonistische biotische Interaktionen und sogar die mikrobiellen Partner der Arten temperaturabhängige Zusammensetzungsprozesse bestimmen können, bleibt ein Großteil dieser komplexen Beziehungen aufgrund methodischer Einschränkungen nach wie vor schlecht verstanden. Gebirge, die als Hotspots der Diversität gelten und von sich rasch verändernden klimatischen Bedingungen bedroht sind, können durch Nutzung der großen regionalen Heterogenität der Klein- und Großklimate als natürliche Experimente dienen, um die Reaktion von Insektengemeinschaften und deren trophischen Interaktionen auf Temperaturänderungen zu untersuchen. Mit dieser Arbeit möchten wir einen Beitrag zum mechanistischen Verständnis der temperaturbedingten Zusammensetzungsprozesse von Insektengemeinschaften leisten, am Beispiel von Heuschrecken, die bedeutende Pflanzenfresser in Grünlandökosystemen der gemäßigten Breiten sind. Hierfür kombinierten wir Felduntersuchungen von Heuschreckengemeinschaften in Grünlandstandorten mit molekularen Methoden zur Rekonstruktion von Nahrungsbeziehungen, wobei wir hauptsächlich die Höhengradienten, die die komplexe Topografie der Berchtesgadener Alpenregion (Bayern, Deutschland) bietet, stellvertretend für Temperaturveränderungen verwendeten (Raum-Zeit-Substitutionsansatz). In diesem Rahmen untersuchten wir die Auswirkungen von Temperaturvariation auf (1) den Artenreichtum, die Abundanz, die Zusammensetzung der Gemeinschaft und die inter- und intraspezifischen Merkmalsmuster, (2) die ökologische Nahrungsspezialisierung und (3) die bis dato vernachlässigte Verbindung zu den mikrobiellen Begleitarten im Kot. Kapitel II: Temperaturabhängige Zusammensetzungsprozesse Das Klima variiert auf verschiedenen Ebenen. Da Veränderungen im Kleinklima oft vernachlässigt werden, haben wir in Kapitel II die Auswirkungen der lokalen Temperaturunterschiede auf die Arten- und Merkmalszusammensetzung von Insektengemeinschaften entlang makroklimatischer Temperaturgradienten untersucht. Hierfür haben wir die Methode der gemeinsamen Artenverteilungsmodellierung verwendet, um zu untersuchen, wie Artmerkmale die Unterschiede in klimatischen Nischen von Heuschreckenarten auf Grünlandstandorten mit gegensätzlichen mikro- und makroklimatischen Bedingungen beeinflussen. Unsere Ergebnisse brachten zwei wichtige Erkenntnisse zutage: (1) additive Auswirkungen des Mikro- und Makroklimas auf die Vielfalt, aber (2) interaktive Effekte auf die Häufigkeit mehrerer Arten, die sich in Zusammensetzungsunterschieden niederschlagen und auf engere klimatische Nischen hinweisen, als es die Höhenverbreitung vermuten lässt. Dieses Kapitel deutet auf positive Auswirkungen einer Erwärmung auf Orthoptera hin, zeigt aber auch, dass das Zusammenspiel von Makro- und Mikroklima eine Schlüsselrolle bei der Strukturierung von Insektengemeinschaften spielt und beide Elemente bei der Vorhersage der Reaktionen von Arten auf den Klimawandel berücksichtigt werden sollten. Darüber hinaus wurden in diesem Kapitel die inter- und intraspezifischen Auswirkungen von Merkmalen auf die Nischen und die Verbreitung von Arten aufgezeigt. Kapitel III: Nahrungsspezialisierung entlang von Klimagradienten Ein entscheidendes Merkmal für die Lage der klimatischen Nische einer Art ist die Nahrungsspezialisierung. Nach der "Hypothese der Höhenlagen-abhängigen Nischenbreite" sollten Arten in hoch gelegenen Lebensräumen weniger spezialisiert sein als ihre Pendants in niedrigen Lagen. Empirische Belege für Verschiebungen in der Spezialisierung von generalistischen, herbivoren Insekten sind jedoch rar und es fehlt eine Berücksichtigung der Häufigkeit und Phylogenie von Interaktionspartnern. In Kapitel III haben wir eine Kombination aus Feldbeobachtungen und Amplikonsequenzierung verwendet, um die Nahrungsbeziehungen von Heuschrecken und Pflanzen entlang eines ausgedehnten Temperaturgradienten zu rekonstruieren. Wir konnten keine engen, sondern flexible Beziehungen zwischen einzelnen Herbivoren- und Pflanzentaxa feststellen. Während die Spezialisierung der Interaktionsnetzwerke mit der Temperatur zunahm, erreichte das korrigierte Muster der Nahrungsspezialisierung auf Gemeinschaftsebene seinen Höhepunkt in mittleren Höhenlagen. Diese differenzierten Ergebnisse zeigen, dass (1) die Verfügbarkeit von Ressourcen, (2) phylogenetische Beziehungen und (3) das Klima intra- und interspezifische empirische Nahrungsbeziehungen und damit die Nahrungsspezialisierung pflanzenfressender Insekten beeinflussen können. In diesem Kontext diskutieren wir, dass die zugrundeliegenden Mechanismen hinter der Nahrungsspezialisierung von herbivoren Insekten entlang von Temperaturgradienten wechseln könnten. Kapitel IV: Verbindungen zwischen Kotbakteriengemeinschaften, Ernährungsgewohnheiten und Klima. Da Darmbakterien die Fitness und Verdauung von Insekten beeinflussen, könnte die Untersuchung deren Vielfalt neue Erkenntnisse über Spezialisierungsmuster liefern. Ihre Verbindung mit Insekten, die sich in ihren Ernährungsgewohnheiten und ihrer Spezialisierung unterscheiden, wurde jedoch noch nie entlang klimatischer Höhengradienten untersucht. In Kapitel IV verwendeten wir Nahrungsinformationen aus Kapitel III, um mit Hilfe von Amplikonsequenzierung Verbindungen zwischen Insekten mit unterschiedlichem Ernährungsverhalten und mikrobiellen Gemeinschaften in deren Kot zu charakterisieren. Sowohl die Nahrung als auch das Klima hatten Auswirkungen auf die bakteriellen Gemeinschaften. Die große Überschneidung der Mikrobengemeinschaften auf Standortebene deutet jedoch darauf hin, dass gemeinsame Bakterien aus der geteilten Nahrungsumgebung, wie z.B. den von den Insekten verzehrten Pflanzen, stammen. Diese Ergebnisse unterstreichen den Einfluss eines breiteren Umweltkontextes auf die Zusammensetzung der mikrobiellen Gemeinschaften im Insektendarm. Kapitel V: Diskussion & Schlussfolgerungen Insgesamt stützen die Kapitel dieser Dissertation die Hypothese, dass klimatische Verhältnisse Pflanzen-Pflanzenfresser-Systeme prägen. Die festgestellten Unterschiede in der taxonomischen und funktionellen Zusammensetzung tragen zu unserem Verständnis der Zusammensetzungsprozesse und daraus resultierenden Diversitätsmustern von Heuschreckengemeinschaften sowie der Mechanismen bei, die deren trophische Interaktionen in verschiedenen Klimazonen strukturieren. Die Kombination der Ergebnisse deutet darauf hin, dass wärmeres Klima eine Zunahme des Heuschreckenartenreichtums in naturnahen Grünlandgebieten Mitteleuropas begünstigen könnte, auch weil die schwachen Verbindungen zwischen den herbivoren Insekten und Pflanzen entkoppelte Arealverschiebungen wahrscheinlich nicht limitieren. Jedoch könnten höhere Temperaturen die Zusammensetzung von Heuschreckengemeinschaften je nach den Merkmalen der Arten wie deren Feuchtigkeitsvorlieben oder der Schlupfphänologie verändern. Darüber hinaus konnten wir nachweisen, dass das Mikroklima für viele Arten eine entscheidende Rolle spielt, da es teilweise engere klimatische Nischen aufdeckt, als ihre Höhenverbreitung vermuten lassen. Wir fanden Hinweise darauf, dass sich nicht nur die Zusammensetzung, Spezialisierung und Merkmale der Heuschreckengemeinschaften entlang der Höhengradienten ändern, sondern dass sogar die mikrobiellen Gemeinschaften im Kot variieren, was eine neue Erkenntnis darstellt. Diese komplexe Umstrukturierung und Neuzusammensetzung von Gemeinschaften in Kombination mit der nichtlinearen Spezialisierung von Interaktionen und einer hohen Vielfalt an assoziierten Bakterien unterstreichen unser noch immer begrenztes Verständnis davon, wie sich Ökosysteme unter zukünftigen Klimabedingungen entwickeln werden, und mahnen zur Vorsicht bei vereinfachten Vorhersagen über die Veränderung der biologischen Vielfalt im Zuge der Klimaerwärmung. Da solche Vorhersagen auf Grundlage unserer Ergebnisse vom Einbezug biotischer Wechselwirkungen und des Mikro- und Makroklimas profitieren können, dürfen Naturschutzverantwortliche eine Verbesserung der mikroklimatischen Bedingungen nicht vernachlässigen, um das lokale Überleben einer Vielzahl bedrohter und anspruchsvoller Arten zu sichern. In diesem Zusammenhang können Berge eine entscheidende Rolle für den Erhalt der biologischen Vielfalt spielen, da sie in räumlicher Nähe heterogene mikroklimatische Bedingungen bieten, die von Arten mit unterschiedlichen Nischen genutzt werden können.
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Komplexní charakterizace subgingiválního plaku - využití moderních sekvenačních metod v diagnostice a sledování léčby onemocnění parodontu. / Complex characterization of subgingival plaque - use of modern sequencing methods in diagnostics and monitoring of treatment of periodontal diseases

Těšínská, Barbora January 2018 (has links)
Periodontitis is a multifactorial inflammatory disease which can result in a complete loss of teeth. Its main cause is the accumulation of bacteria from the dental plaque followed by massive reaction of the host immune system. It was proved that the composition of oral microbiome (OM) differs in periodontally healthy individuals and patients with periodontitis. This work aims to solve specific parts of the long-term project concerning the taxonomic composition of the OM of periodontally healthy individuals and patients with chronic and aggressive form of the disease. The OM was characterized based on 16s rDNA sequencing. It is evident from the results that the shift in the OM composition occurs prior the development of clincal signs of the disease and that the precise dental care can significantly postpone or even avoid the onset of the disease. When comparing the OM composition in individuals with chronic and aggressive periodontitis, no remarkable differences were detected to explain the faster progress of the aggressive form of the disease. This work also aimed to compare the results obtained by 454 pyrosequencing and Illumina. Both sequencing methods were found to provide statistically comparable results. Illumina MiSeq thus can be employed to build on the former results of the long-term study...
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Změny střevního mikrobiomu u pacietů s idiotypickými střevními záněty léčenými pomocí anti-TNF-α / Změny střevního mikrobiomu u pacietů s idiotypickými střevními záněty léčenými pomocí anti-TNF-α

Damašková, Dagmar January 2016 (has links)
English Abstract Crohn's disease together with ulcerative colitis, is a type of inflammatory bowel disease (IBD) with increasing incidence and prevalence in developed countries. IBD is an immunologically mediated multifactorial disease and it's mechanism of action is still unknown. Current well- established treatment targets the inflammation with corticosteroids and immunosuppressive drugs. Apart from the intestinal inflammation, which is the primary target of the treatment, patients are characteristically afflicted with intestinal dysbiosis. Therefore, possible interventions might be an adjuvant or biological therapy. Adjuvant therapy directly aims the microbiota with probiotics, whereas the target of biological therapy is TNF-α, a pro- inflammatory cytokine excessively secreted by macrophages. The aim of this thesis is to evaluate intestinal microbiota composition changes in IBD patients with regard to courses of adjuvant and biological therapy. Bacterial diversity was analyzed using three different DNA extraction techniques. Rapid beat beating + column (RBB+C) was chosen for analyzing patient samples, as it showed the highest DNA yield and the highest DNA purity. Primarily the bacterial diversity was analyzed using degradation gradient gel electrophoresis (DGGE) with subsequent sequencing of bands of...
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Analyzing the microbiota-mediated effects of environmental chemicals on MAIT cells

Krause, Jannike Lea 10 August 2021 (has links)
No description available.
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Diverzita anaerobních nálevníků podtřídy Scuticociliatia a jejich symbiontů / The diversity of anaerobic ciliates from the subclass Scuticociliatia and their symbionts

Poláková, Kateřina January 2020 (has links)
Ciliates are the most diversified protists in suboxic and anoxic habitats where they often form symbioses with prokaryotes. Although the diversity of anaerobic ciliates has been overlooked for a long time, anaerobic representatives can be found in most ciliate classes. This study focuses on anaerobic ciliates from the subclass Scuticociliatia, a neglected lineage, which belongs to the species-rich class Oligohymenophorea. One of the main outcomes resulting from this study is the discovery of a novel anaerobic clade of ciliates, from which only one species has been described molecularly to date. We have shown that the clade represents a diversified lineage, likely a new order. Thanks to the sampling of many freshwater and marine anoxic sediments, we have established the largest culture collection of anaerobic scuticociliates in the world. This has enabled us to determine the 18S rRNA gene sequences of 55 cultured anaerobic scuticociliates and to study their morphology both in-vivo and using various silver- impregnation methods. Besides, we applied transmission and scanning electron microscopy techniques to study the ultrastructure of both ciliates and symbionts. To identify the symbionts, we also employed other methods including microbiome sequencing and fluorescence in-situ hybridization. Since all...
16

Kolonizace lidských plic nepatogenními streptomycetami / Colonization of human lung by non-pathogenic streptomycetes

Herbrík, Andrej January 2019 (has links)
Streptomycetes, primary soil saprophytic microorganisms are at the center of interest in many research groups, mainly because of their ability to produce a wide range of biologically active substances useful in medicine, biotechnology and agriculture. The marginal, and little explored areas are the interactions that streptomycetes create with humans. Recent metagenomic studies have shown that streptomycetes colonize the skin, the respiratory and possibly the urogenital tract of humans. In addition to apparent pathogens such as S. somaliensis and S. sudanensis, the clinical impact of these streptomycetes on human health is unknown. For this reason, a unique collection of non-pathogenic streptomycetes isolated from human clinical specimens was developed. The isolates were collected by the National Reference Laboratory for Pathogenic Actinomycetes in Trutnov, Czech Republic. On the basis of pilot studies, an isolate labeled TR42 was selected from the Trutnov collection, showing a very broad spectrum of biological activities. This strain was isolated from sputum from a patient with unknown respiratory diagnosis. The TR42 strain exhibits considerable biotechnological potential and after following a thorough study, it could be a source of new biologically active substances with pharmaceutically...
17

Střevní mikrobiota a poruchy nálady / Intestinal microbiota and mood disorders

Ambrožová, Lucie January 2016 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Lucie Ambrožová Supervisor: Doc. MUDr. Josef Herink, DrSc. Title of diploma thesis: Intestinal microbiota and mood disorders The intestinal microbiom is composed mainly of two dominated strains - Bacteroidetes and Firmicutes. The other strains are just not numerous like the previous ones. The specimens have the invariable core of microbiom which doesn't change in time. Nevertheless they have also the transient gut bacteria, which change during their life. Intestinal microbiom is influenced by many factors. Between them we can categorize for example the way of the childbirth, the breast - feeding, the alimentation, the state of health, and the medicaments. Every specimen has own specific microbiom. It was found that human population is possible to divide into three intestinal groups or enterotypes. To each enterotype dominates different bacterial strain. It was proved that intestinal microbiom communicates with the brain and it works also vice versa. This communication system is called "brain - intestine" and takes several ways in several body systems (such as nervous, endocrine, metabolic, and immune). To normal development of the brain is needed the right colonisation of non...
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Úloha střevního mikrobiomu v imunitních onemocněních centrálního nervového systému / The role of the gut microbiome in immune-mediated CNS disorders

Zedníková, Barbora January 2016 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Candidate: Bc. Barbora Zedníková Supervisor: Doc. MUDr. Josef Herink, DrSc. Title of diploma thesis: The role of the gut microbiome in immune-mediated CNS disorders Human body hosts a large number of microorganisms - i.e. Archea, Eukarya, Bacteria and viruses. These microorganisms form microbiome, the total number of the microorganisms is ten times higher than the number of all human cells. Largest part of the microbiome is located in the intestine. The current development of molecular genetics revealed the close relationship between intestinal microbiome and health. Recent studies the most recent studies have pointed to a connection with the pathogenesis of various diseases. This dissertation is focused on the connection between intestinal microbiome and autoimmune diseases of the central nervous system. Research shows that the key factor are the ongoing changes in the composition of microbiome. These changes lead to increased immune stimulation and thereby to inflammatory proliferation.
19

Vliv tenzidů a kosmetických polysacharidů na parametry pleti a její mikrobiom / Influence of surfactants and cosmetic polysaccharides on skin parameters and human skin microbiome

Pilipenco, Alina January 2020 (has links)
The aim of this diploma thesis was to investigate the effect of surfactants and cosmetic polysaccharides on skin parameters and its microbiome. Three surfactants were tested to determine their effect: Sodium Dodecyl Sulfate (SDS), Cocamidopropyl Betaine (CAPB), Decylglucoside (DG). Distilled water was also used for comparison. For the next part of the experimental work were selected 6 polysaccharides: high molecular weight Hyaluronic Acid (HMW HA), very low molecular weight Hyaluronic Acid (VLMW HA), Sodium Caproyl Hyaluronate (CaproylHA), Sodium Carboxymethyl -Glucan (NaCMG), Schizophyllan and Glucomannan. For comparison, placebo and untreated control (only CAPB treatment) were also included in the tests. The first part of the work is a literature search on the assigned topic, which contains the following parts: skin anatomy and its biophysical properties, skin microbiome and its functions, description of used surfactants and polysaccharides. The experimental part is mainly focused on bioengineering methods for evaluation of skin parameters and qRT-PCR to determine the relative proportion of main bacterial species of skin microbiome. First, the effect on the CT gene of 16S rDNA was analysed, and Propionibacterium acnes and Staphylococcus epidermidis strains were selected for further analysis. In conclusion are presented an overview of all properties of selected substances and assessment of their application in cosmetics.
20

Lokální steroidogeneze v periferních tkáních a její regulace / Local steroidogenesis in peripheral tissues and its regulation

Langová, Veronika January 2018 (has links)
The innate and adaptive immune processes are modulated by hormones including glucocorticoids and by microbiota. The exact mechanisms underlying the microbial and hormonal contributions to this control are not completely clear. Present study is therefore focused to crosstalk between microbiota and de novo biogenesis or local regeneration of glucocorticoids. In particular, the study analysed the effect of commensal microbiota on expression of genes encoding steroidogenic enzymes (Star, Cyp11a1, Hsd3b1, Cyp21a1, Cyp11b1) and regeneration of glucocorticoids (Hsd11b1) in adrenal glands, colon, spleen and mesenteric lymph nodes using conventional and germ-free mice. The expression of all 5 components of steroidogenesis was identified only in the adrenal gland and colon, whereas the lymphoid organs expressed predominantly Star, Cyp11a1 and Hsd3b1 indicating the ability to produce only progesterone but not corticosterone. Microbiota decreased the expression of Star in all studied tissues but the expression of other genes was insensitive to microbiota or did not respond homogenously depending on the tissue and gene. Hsd11b1 expression was upregulated by microbiota in the spleen but not in other tissues. Similarly, the in vitro treatment of immune cells isolated from mesenteric lymph nodes by microbial...

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