Biofilm formation in the thermoacidophilic crenarchaea Sulfolobus spp.

In dieser Studie wurden Biofilmanalysen an Crenarchaeota durchgeführt, welche die ersten tiefergehenden Untersuchungen an archaealen Biofilm überhaupt sind. Es wurden Methoden für die Analyse von Biofilm entwickelt, wie zum Beispiel der Mikrotiter Assay, CLSM und das Färben zur Detektion von Biofilm. Die verwandten Stämme S. solfataricus, S. acidocaldarius und S. tokodaii zeigten erhebliche Unterschiede in ihrer Biofilmarchitektur (von teppich- bis zu turmartigen Strukturen), im Protein- und Transkriptionsmuster, als auch im Bedarf von Zellanhängen für die Biofilmentwicklung. In der Biofilmmatrix konnten hohe Anteile an Zuckern (Mannose-, Glucose-, N-acetyl-D-glucosamin- und Galactosylreste) detektiert werden, wobei derzeit noch unklar ist, ob diese Zucker auf Exopolysaccharide, glykosylierte Proteine oder beides zurückzuführen sind. Zusätzlich wurden in der Biofilmmatrix geringe Mengen an eDNA nachgewiesen, die allerdings nicht für die Stabilität und Struktur des Biofilms benötigt werden. Auffällig war, dass alle Stämme unterschiedliche Reaktionen im Biofilm unter Stressbedingungen zeigten (Temperatur, pH und Eisen). Gene, die möglicherweise in Archaea generell eine Rolle in der Biofilmbildung spielen sind der Transkriptionsregulator Lrs14 und FabG, welches möglicherweise an einem neuartigen „quorum sensing system“ von Archaeen beteiligt ist. Weitere interessante Beobachtungen wurden bei der Analyse von Mutanten und dem Einfluss von Oberflächenstrukturen auf Biofilm Formation und Anheftung gemacht. Während S. solfataricus sowohl die Flagelle als auch den Ups-Pilus für die Anheftung an Oberflächen benötigt, sind diese für die weitere Biofilmformation weniger essentiell. Ein anderes Ergebnis wurde bei S. acidocaldarius erzielt, wo die Deletion von mindestens zwei Anhängen zu einer reduzierten Anheftung führte. Eine Ausnahme war hier das Anheften das bei Mutanten beobachtet wurde, die nur noch den Aap-Pilus besaßen (Steigerung um 150%). Die einzelnen Deletion von Oberflächenstrukturen hatte zudem auch Einfluss auf die Biofilmarchitekturen (drei verschiedene Phänotypen). Ein GFP wurde adaptiert und bietet nun die Möglichkeit für Biofilm Analysen von S. acidocaldarius. Abschließend hat eine in vivo Analyse der Ssα-man einen Einfluss auf die Zuckerzusammensetzung des EPS in S. solfataricus ergeben. Wobei aufgrund der erzielten Ergebnisse, nicht auszuschließen ist, dass dieses Protein in Sulfolobus spp. an einer möglichen Prozessierung des Glycan beteiligt ist

European microbiologically influenced corrosion network (EURO-MIC): new paths for science, sustainability and standards

ABSTRACT: Microbiologically influenced corrosion (MIC) is the corrosion of material caused or enhanced by microorganisms. It occurs directly or indirectly through their metabolic activities and can be accelerated 10 to 100 times, depending on the material. A wide range of materials can be affected by MIC, including metal, plastic, and concrete, impacting the entire infrastructure of society, including water and wastewater management systems, marine industrial facilities, and (on)offshore systems. One challenge of MIC common to all these sectors is the colonization of surfaces, where the presence of water is one of the basic requirements for biofilm to form. This phenomenon is a major global challenge caused by the growing world population and related industrial activities combined with climate change, and increasingly becoming a problem for our society [1] and [2]. The global cost of MIC is unambiguous and should almost certainly be underestimated. According to survey data, MIC is responsible for up to 20% of all corrosion found in aqueous systems, costing billions of dollars in rehabilitation costs alone [1]. In Europe, several research groups/ other industrial stakeholders are already dealing with MIC. Unfortunately, the discussions are fragmented, and the exchange of information is limited. A true transdisciplinary approach is hardly ever experienced, although this would be logical for this material/biology related challenge. Therefore, Europe needs to combine the efforts of experts in different fields and develop prevention measures according to the european rules, in close cooperation with industry, plant operators and owners of critical infrastructure to effectively contribute to this MIC challenge. In this context, our european MIC-network aims to provide the necessary interaction and communication, knowledge sharing, training of personnel and of researchers of different disciplines. Only in this Europe can get a leading role in this process, bringing ideas together on an equal level with other nations, and thereby considering the important values and attitudes for Europe (e.g., environmental protection) and resulting in a greater protection for people, property, and the environment. The working group structure of this Euro-MIC Cost Action, as well as specific objectives, ongoing activities, and expected impacts, will be presented.info:eu-repo/semantics/publishedVersio

Evaluation der Expression von EGFR, HER-2/NEU, p53 und CD117 zur Therapieprädiktion bei Riesenzelltumoren des Skelettsystems

Die vorliegende Studie untersucht die prognostische Relevanz der Antikörper EGFR, HER-2/NEU, CD117 und p53 bei Riesenzelltumoren des Knochens, um Aussagen über die potentielle Wirksamkeit molekularer Therapien treffen zu können. EGFR, p53, HER-2/NEU und die transmembrane Tyrosinkinase CD117 regulieren die Zellproliferation und Apoptose. Eine Fehlregulation dieser Faktoren kann zu unkontrolliertem tumorösen Wachstum führen. Hier kann eine molekulare Therapie zielgerichtet wirken. Keine Expression war nachweisbar für HER-2/NEU, EGFR und CD117. p53 wurde in 27,7% der Riesenzelltumoren exprimiert. Anhand der vorliegenden immunhistochemischen Charakterisierung von 112 ossären Riesenzelltumoren erscheinen HER-2/NEU, CD117, EGFR und p53 nicht als mögliche Kandidaten zielgerichteter molekularer Therapien, da auch keine Korrelation der Antikörper mit den klinischen Parametern (Metastasierungen oder Lokalrezidiven) besteht

Crenarchaeal Biofilm Formation under Extreme Conditions

Background: Biofilm formation has been studied in much detail for a variety of bacterial species, as it plays a major role in the pathogenicity of bacteria. However, only limited information is available for the development of archaeal communities that are frequently found in many natural environments. Methodology: We have analyzed biofilm formation in three closely related hyperthermophilic crenarchaeotes: Sulfolobus acidocaldarius, S. solfataricus and S. tokodaii. We established a microtitre plate assay adapted to high temperatures to determine how pH and temperature influence biofilm formation in these organisms. Biofilm analysis by confocal laser scanning microscopy demonstrated that the three strains form very different communities ranging from simple carpet-like structures in S. solfataricus to high density tower-like structures in S. acidocaldarius in static systems. Lectin staining indicated that all three strains produced extracellular polysaccharides containing glucose, galactose, mannose and N-acetylglucosamine once biofilm formation was initiated. While flagella mutants had no phenotype in two days old static biofilms of S. solfataricus, a UV-induced pili deletion mutant showed decreased attachment of cells. Conclusion: The study gives first insights into formation and development of crenarchaeal biofilms in extrem

Labial Salivary Glands in Infants: Histochemical Analysis of Cytoskeletal and Antimicrobial Proteins

Human labial glands secrete mucous and serous substances for maintaining oral health. The normal microbial flora of the oral cavity is regulated by the acquired and innate immune systems. The localization and distribution of proteins of the innate immune system were investigated in serous acinar cells and the ductal system by the method of immunohistochemistry. Numerous antimicrobial proteins could be detected in the labial glands: -defensin-1, -2, -3;lysozyme;lactoferrin;and cathelicidin. Cytoskeletal components such as actin, myosin II, cytokeratins 7 and 19, - and -tubulin were predominantly observed in apical cell regions and may be involved in secretory activities

Проблемы информационного обеспечения физической культуры и спорта

A formation process for semiconductor quantum dots based on a surface instability induced by ion sputtering under normal incidence is presented. Crystalline dots 35 nanometers in diameter and arranged in a regular hexagonal lattice were produced on gallium antimonide surfaces. The formation mechanism relies on a natural self-organization mechanism that occurs during the erosion of surfaces, which is based on the interplay between roughening induced by ion sputtering and smoothing due to surface diffusion

Prevalence of dental caries in children with congenital heart disease

Background: Congenital heart defects (CHD) affect about 8 out of 1000 births worldwide. Most of the patients reach adulthood and are exposed to an increased risk of endocarditis. Since bacteria already enter the bloodstream during everyday activities, oral hygiene is given special importance in the prevention of endocarditis. Methods: In this study 81 boys (55.1%) and 66 (44.9%) girls with CHD received a dental exam and additionally an assessment using the DIAGNOdent (R) pen. This study group consisting of patients with CHD was matched with a healthy epidemiological control group in Germany. Results: Eighty-one boys (55.1%) and 66 (44.9%) girls were examined. The mean age was 11 & PLUSMN; 4 years. 38.8% showed at least one untreated carious lesions. 37.4% had a dmft/DMFT & GE;2 and thus represented a group with an increased caries risk. The dmft value was 2.12 & PLUSMN; 1.25 in the age group 3-6 year olds. In the group of the 7-12 year old patients the DMFT/dmft was 2.06 & PLUSMN; 2.27, whereas DMFT in 13-17 year olds was at 2.12 & PLUSMN; 1.58. However, children and adolescents with CHD had a higher DMF index than healthy children in the same age group. Conclusions: The present study reveals that more than one third of those examined have a dental condition in need of rehabilitation. In future, close interdisciplinary cooperation between pediatric cardiologists and dentists should ensure regular dental check-ups

A dental myth bites the dust - no observable relation between the incidence of dental abscess and the weather and lunar phase: an ecological study

Background: Anecdotal reports assert a relationship between weather and lunar activity and the odontogenic abscess (OA) incidence, but this relationship has not been validated. Therefore, the present study investigated the relationship between oral pain caused by OA and a variety of meteorological parameters and cyclic lunar activity. Methods: The records of all dental emergency patients treated at the AllDent Zahnzentrum Emergency Unit in Munich, Germany during 2012 were retrospectively reviewed. Patients with oral pain who were diagnosed with OA and treated surgically (n = 1211) were included in the analysis. The OA incidence was correlated to daily meteorological data, biosynoptic weather analysis, and cyclic lunar activity. Results: There was no seasonal variation in the OA incidence. None of the meteorological parameters, lunar phase, or biosynoptic weather class were significantly correlated with the OA incidence, except the mean barometric pressure, which was weakly correlated (rho = -0.204). The OA incidence showed a decreasing trend as barometric pressure increased (p < 0.001). On multiple linear regression, the barometric pressure accounted for approximately 4% of the OA incidence. Conclusion: There is no evidence supporting a correlation between the incidence of odontogenic abscess and the weather and lunar activities