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Complications associated with indwelling intravenous catheters vary from minor to severe. Changes in tissue architecture and vein structure may be detectable prior to clinical alterations. The aim of the study was to characterize and compare changes in a catheterized vein and surrounding tissue by clinical and ultrasonographic examination. Microbiological infestation of catheter specimens was assessed.In this prospective, observational, clinical study 55 horses with an indwelling intravenous catheter have been included. Subsequent to catheter placement, vein and surrounding tissue were daily examined clinically and by ultrasonographic examination at predetermined localizations. After sterile removal of the catheters, specimens underwent microbiological testing and scanning electron microscopy. Obtained data were analyzed via descriptive statistics. Thickness of the venous wall was compared at predetermined localizations and time points for several parameters with the help of non-parametric tests (level of significance at p 0.05, post-hoc Bonferroni correction).Overall, in 41.8 % of the horses transient alterations (swelling) of the surrounding tissue occurred during catheterization. Median catheterization was 69.5 hours (19 hour-10 days). With ultrasonography, venous valves and collateral vessels could be detected reliably. Significant alterations in wall thickness during catheterization were associated with various factors (location site [p ≤ 0.001], season [p = 0.006], anesthesia [p ≤ 0.001]).Microbiological analysis revealed a positive result in 23.5 %, 12 of the 51 samples; raster electron microscopy showed presence of bacteria in 25.0 %, 4 of the 16 investigated catheter samples.Local tissue changes at the insertion site of the catheter are commonly associated with catheterization, and are easily detectable with ultrasonography. Despite the easy performance in a clinical setting, the benefit of routine ultrasonographic monitoring of catheterized veins might be questionable with regard to early identification and prediction of catheter-associated venous disease. Bacteria might be detectable morphologically on the catheter but frequently lack a positive result from standard bacterial cultivation.Die Nutzung intravenöser Verweilkatheter ist trotz größter Sorgfalt mit Komplikationen verbunden. Gewebeveränderungen und minimale Entzündungsreaktionen an der Vene können bereits vor klinisch erkennbaren Veränderungen auftreten. Ziel dieser Studie war es, die Vena jugularis während und nach der Katheterisierung klinisch und ultrasonografisch zu beurteilen und eine mögliche bakterielle Besiedlung des Katheters zu evaluieren.In einer prospektiven Beobachtungsstudie wurden 55 Pferde mit einem Venenverweilkatheter täglich klinisch und ultrasonografisch untersucht. Die steril entfernte Katheterspitze wurde mikrobiologisch mittels Anzucht sowie morphologisch in der Rasterelektronenmikroskopie untersucht. Die erhobenen Daten wurden deskriptiv analysiert und die Venenwanddicke an verschiedenen Lokalisationen und Zeitpunkten hinsichtlich verschiedener Parameter mit nicht-parametrischen Tests verglichen (Signifikanzniveau p 0,05; Bonferroni-Korrektur bei multiplem Testen).Die Verweildauer des Katheters betrug zwischen 19 Stunden und 10 Tagen (Median 69,5 Stunden). Es konnten keine behandlungswürdigen Venenerkrankungen beobachtet werden, lediglich transiente geringgradige Gewebeveränderungen traten bei 41,8 % der Patienten auf. Im Ultraschall konnten Venenklappen und Kollateralgefäße zuverlässig dargestellt werden. Lokalisation (p ≤ 0,001), Jahreszeit (p = 0,006) und Allgemeinanästhesie (p ≤ 0,001) hatten einen signifikanten Einfluss auf die im Ultraschall gemessene Venenwanddicke, welche an der Einstichstelle verbreitert war. Der Nachweis von Bakterien war positiv in 23,5 % (12/51 Proben, mikrobiologische Anzucht) bzw. 25,0 % (4/16 Proben, Rasterelektronenmikroskopie).Jeder Katheter erzeugt eine Entzündungsreaktion der Venenwand und des umliegenden Gewebes. Diese Veränderungen können vor allem in der ultrasonografischen Untersuchung dargestellt werden, welche eine praxistaugliche Diagnostik darstellt. Eine Vorhersage über sich entwickelnde Venenerkrankungen war bei den untersuchten Probanden nicht möglich. Die Ergebnisse der Rasterelektronenmikroskopie zeigen, dass nicht in jedem Fall morphologisch auf dem Katheter erkennbare Bakterien auch in der Kultivierung nachgewiesen werden können.

«Guided Biofilm Therapy» (GBT) represents a systematic, risk and demand-oriented prophylaxis and treatment concept. A significant difference to conventional methods is - above all - the reduced, tissue-friendly and targeted use of ultrasound and hand instruments. The biofilm is consistently shown with suitable color solutions, the oral hygiene instruction and professional tooth cleaning is optimized. The use of suitable powders guarantees a tissue-conserving and targeted removal of biofilm. While individual treatments, techniques and materials have already been well investigated and described, little data is available on patient acceptance. The aim of the present study was to gain an impression of the acceptance of this method in comparison to the conservative-classical recall care mainly based on hand and ultrasound devices in a survey of 100 consecutive patients from the clinic's internal recall system. The overall results were very positive. The powder jet device showed the best acceptance. The aspect fear before/during the recall session was also interesting: At a low level (10%), an additional reduction to 4% occurred, since hand instruments were probably used much less and only very specifically. mConclusion: The use of plaque elevators makes the work in the recall session more efficient, more effective and guarantees ma higher quality control, which is also highly appreciated by patients.

Biofilme aeroterrestrischer Mikroorganismen stellen im nicht-medizinischen Bereich ein ständig größer werdendes Problem dar. Sie tragen ebenfalls wesentlich zur Verwitterung von Fassaden bei und verursachen durch die daraus resultierende Notwendigkeit der Entfernung des Biofilms und Instandsetzung der Fassaden hohe Kosten. Auch das von Biofilmen auf Innenwänden von Gebäuden ausgehende Gesundheitsrisiko für den Menschen ist schwerwiegend. Solarzellen sind aufgrund ihrer rauen Glasoberfläche ebenfalls ein bevorzugter Siedlungsort für Biofilme. Auf diesen können sie durch Verschattung die Effizienz der Solarzellen deutlich herabsetzen. Die Entfernung von Biofilmen erfordert vor allem den Einsatz von Bioziden, welche ihrerseits eine Belastung für die Umwelt darstellen und zudem oft nur begrenzte Wirksamkeit zeigen. Ziel dieser Arbeit ist daher, das Potenzial der Photodynamischen Inaktivierung (PDI) als alternative Methode zur Beseitigung oder zur Prävention der Bildung von Biofilmen zu bestimmen. Dazu wurden unterschiedliche Photosensibilisatoren (PS) bezüglich ihrer Phototoxizität auf im Rahmen dieser Arbeit etablierte phototrophe Modellkulturen in Suspension, subaquatischen und subaerialen Biofilmen untersucht. Neben der Entwicklung der Biomasse während der PDI wurde mittels spektroskopischer Methoden zudem die Aktivität der Kulturen sowie die EPS-Sekretion und die Biofilmbildung gemessen. Dabei konnte gezeigt werden, dass die kationischen PS PCor+ und TMPyP zur PDI phototropher Kulturen erfolgreich genutzt und die Biofilmbildung verhindert werden kann. Es wurde gezeigt, dass dieses Resultat ohne Aufnahme der PS in die Zellen erzielt wird. Dies ist bezüglich der Vermeidung einer möglichen Resistenzentwicklung der Mikroorganismen von entscheidender Bedeutung. Somit wurden mit dieser Arbeit die Voraussetzungen für die Entwicklung photodynamisch aktiver, antimikrobieller Oberflächenbeschichtungen zur Prävention des Wachstums aeroterrestrischer Biofilme geschaffen., Biofilms of aeroterrestrial microorganisms are an ever-increasing problem in non-medical applications. They also contribute significantly to the weathering of facades and cause high costs due to the resulting necessity of removing the biofilm and repairing the facades. Furthermore, the health risk for humans caused by biofilms on interior walls of buildings is serious. In addition, solar cells are a preferred location for biofilms due to condensation on their rough glass surface. Growing there, they can significantly reduce the efficiency of the solar cells by shading, a problem which gains even more importance with increasing operating times of solar modules. In the removal of biofilms, biocides are prevalent. They are in turn a burden on the environment and often show only limited effectiveness. The aim of this work is therefore to determine the potential of Photodynamic Inactivation (PDI) as an alternative method to eliminate or prevent the formation of biofilms. Different Photosensitizers (PSs) were investigated with respect to their phototoxicity on phototrophic model cultures established in suspension, subaquatic and subaerial biofilms. In addition to biomass development during PDI, spectroscopic methods were used to measure culture activity, EPS secretion and biofilm formation. It was shown that the cationic PSs PCor+ and TMPyP can be successfully used for PDI of phototrophic cultures and that biofilm formation can be prevented. It has been shown that this result is achieved without uptake of PS into the cells. This is of decisive importance with regard to the avoidance of a possible resistance development in the microorganisms. Thus, this work created the prerequisites for the development of photodynamically active, antimicrobial surface coatings for the prevention of the growth of aeroterrestrial biofilms.

The high demands that fracture-related infections put on patients, physicians and the healthcare system have led to the establishment of a international group of experts called the Fracture-Related Infection (FRI) Consensus Group, whose aim is to develop evidence-based treatment recommendations.Fracture-related infections are classified according to the time of occurrence, extent and treatment options. The diagnostic algorithm distinguishes between confirmatory and suggestive diagnostic criteria. If there are indications of an infection, tissue biopsy with microbiological and histological workup is recommended to confirm the diagnosis.The primary objective of FRI treatment is to achieve fracture consolidation, while avoiding osteomyelitis. Therapeutic options are removal of the implant, eradication of the infection with implant retention or suppression of FRI. A multidisciplinary team is recommended to develop a patient-specific, optimized surgical and antimicrobial therapy.

Long-term human missions to space require methods for sustaining the health and safety of the crew. Therefore, microbiological monitoring and reduction of contamination is necessary. Microbial biofilms are of special interest because they can cause damage to spaceflight equipment and are difficult to eliminate due to their increased resistance to antibiotics and disinfectants. The introduction of antimicrobial surfaces for medical, pharmaceutical, and industrial purposes has shown a unique potential for reducing and preventing biofilm formation. The European Space Agency (ESA) launched the BIOFILMS-project, which is evaluating the effect of microgravity on biofilm formation on non-inhibitory surfaces, such as steel, and on antimicrobial metal surfaces. These surfaces are composed out of different metals with and without nanostructures. For the project, human-relevant bacterial strains were selected. One of the selected strains is Staphylococcus capitis subsp. capitis K1-2-2-23, which was isolated from the International Space Station (ISS) on V2A steel and is forming strong biofilms. A comparison of this strain to the DSMZ type strain revealed several differences that include colony pigmentation, increased growth, and tolerance to desiccation. Furthermore, tests with S. capitis subsp. capitis strain K1-2-2-23 within the BIOFILMS hardware revealed that the hardware is biocompatible and allowed biofilm formation on steel surfaces. Additionally, the use of pure copper and brass surfaces inside the hardware led to a significant reduction in growth and biofilm formation, whereby nanostructured copper surfaces were observed to be more effective. The obtained results lay the foundation for the BIOFILMS spaceflight project that will be conducted aboard the International Space Station and may provide suitable antimicrobial surfaces for spaceflight purposes.

Gravity is the most consistent physical parameter to which all life has so far been subordinated and has not changed from the beginning of evolution to the present day. Since Apollo 16 the Gram-positive bacterium Bacillus subtilis has been used to study the influence of gravity on vegetative cells, spores and biofilms and still it remains unclear to what extent biofilm formation is influenced by the loss of gravity. As a model, B. subtilis can be used to investigate the intrinsic resistance of biofilms under space conditions. Biofilms are a challenge in medicine and in industry and with increasing space activities and manned long-term missions or even moon bases, new insights into the behavior of biofilms under altered gravity conditions are becoming increasingly important. We used B. subtilis NCIB 3610 as spore and biofilm-forming model organism as well as biofilm deficient mutants to investigate the influence of simulated microgravity (sim-µg) on structural and resistance properties. For the simulation, a fast-rotating 2-D clinostat was used in combination with a standardized method for growing and harvesting biofilms on filter membranes to achieve highly reproducible results. By comparing biofilm growth under normal gravitational conditions (1g) and sim-µg, the results of profilometry showed no significant changes in biofilm topography. Scanning electron microscopic images of biofilm cross-sections and transmission microscopic analyses showed differences in the internal biofilm structure. Typical biofilm properties such as matrix development in the basal regions of biofilms were increased in sim-µg. Growth and resistance properties of biofilms grown under sim-µg showed small differences, but hydrophobicity values were significantly increased under simulated microgravity. Spores isolated after sim-µg treatment showed homogeneous germination behavior in contrast to 1g spores and tended to germinate more spontaneously.

The European Space Agency's EXPOSE facility, located on the outside of the International Space Station, was used to investigate the survival of cell aggregates of a cyanobacterium, Gloeocapsa sp., in space and simulated martian conditions for 531 days in low Earth orbit as part of the "Biofilm Organisms Surfing Space" (BOSS) experiments. Postflight analysis showed that the cell aggregates of the organism conferred protection against space conditions compared to planktonic cells. These cell aggregates, which consisted of groups of metabolically inactive cells that do not form structured layered biofilms, demonstrated that disordered "primitive" aggregates of sheathed cells can provide protection against environmental stress such as UV radiation. Furthermore, the experiment demonstrated that the cyanobacterial cell aggregates provided a microhabitat for a smaller bacterial co-cultured species that also survived in space. This observation shows that viable cells can "hitchhike" through space within the confines of larger protecting cells or cell aggregates, with implications for planetary protection, human health, and other space microbiology applications.

An enduring human presence in space is required to achieve many goals of ESA´s and NASA´s space programs. During long-term missions, astronauts are exposed to various conditions such as microgravity, radiation, sleep-disruption, insufficient nutrition and also microbial contamination. Since astronauts´ immune function is compromised, all these factors increase the health risk for the crew. Therefore, improved spaceflight-suitable methods for microbiological monitoring, hygiene and decontamination are important. Microbial biofilms are of particular concern in spaceflight, because they cannot only cause damage to equipment but also be a risk for human health. Certain metals have antimicrobial properties such as copper and its respective alloys and therefore, prevent the formation of biofilms. However, precise evaluation of suitable antimicrobial materials for space flight is essential. Within the ESA project BIOFILMS (“Biofilm Inhibition on Flight equipment and on board the ISS using microbiologically Lethal Metal Surfaces"), effects of microgravity on biofilm formation on tailor-made nanostructured metallic surfaces are going to be examined. For that, human-associated microorganisms and antimicrobial surfaces with different chemical compositions and geometric nanostructures are selected. Experiments will be conducted aboard the ISS, where microbial growth will occur under optimal biofilm inducing conditions inside a particular designed hardware. The selected antimicrobial surfaces are supposed to be tested under different spaceflight-relevant gravitational regimes. Here, preliminary experiments with Staphylococcus capitis subsp. capitis for the BIOFILMS project will be presented. S. capitis forms biofilms and is related to infections such as endocarditis, urinary tract infections and catheter induced bacteremia. The reduction of growth and biofilm formation under the influence of copper-based, nanostructured surfaces was investigated.