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The state of the art of studying the health effects of aerosols in vitro is based on submerged exposure of collected particulate matter, suspended in culture medium. However, this method neglects the gas phase including their interactions with particles and cells. It may change the properties of the investigated particles and does not represent the actual process in the human lung. Exposure at the Air-Liquid Interface (ALI) avoids these disadvantages, but requires a comprehensive system to guarantee reproducible conditions. Therefore, KIT and VITROCELL Systems developed a fully automated ALI exposure station. The exposure station offers a complete measurement system for parallel exposure of up to 24 human lung cell cultures towards gases, nanoparticles and complex mixtures such as combustion aerosols. The aerosol flow, temperature, and humidity are adjusted to the conditions resembling the human lung. An internal negative control using humidified synthetic air is also implemented and the particle dose per time can be increased by electrostatic particle deposition. The particle mass per area deposited by diffusional as well as by electrostatic mechanism is monitored online using a quartz crystal microbalance. Additionally, a new tool to reproducibly expose sample grids for transmission electron microscopy was developed and applied. Image evaluation of TEM images delivers dose information with respect to the spatial distribution and the agglomeration state of the deposited particles. Applications of the ALI exposure station are environmental atmospheres and technical emission sources like marine diesel engines or wood combustion. Long-term stability of A549 lung cells was examined for exposure times up to 24 hours by exposing A549 cell cultures towards clean air as well as towards airborne titanium dioxide and copper oxide nanoparticles. Dose measurement data and biological responses as viability (AlamarBlue assay), cytotoxicity (LDH release), and release of cytokines during long-term exposure are reported.

Adding nanoparticles to polymers improves the properties significantly, such as UV resistance or even electrical conductivity. The growing use of these composite materials leads to a higher amount in disposals eventually. Within the circular economy there are two ways of handling: the recycling by shredding and reuse and the thermal treatment by combustion in municipal waste incinerators. In both cases there is nearly no information about the behavior of the nanoparticles and possible release scenarios. In this study a laboratory burner is used as a flexible set up to incinerate the polymer nanocomposites. The flue gas containing a complex mixture of combustion gases and particles is characterized by different particle analysers, PAH analysis, VOC analysis and TEM. The biological impact is studied by using a VITROCELL Automated ALI exposure station. Hereby, cells of the adenocarcino cell line A549 as well as a reconstituted bronchial epithelium (MucilAir, Epithelix) were exposed for 4 hours to the aerosols emitted from the combustion process. Within the exposure process, cells were exposed to the native aerosol, an aerosol under conditions to increase particle deposition via high voltage as well as a filtered aerosol, and therefore the sole gaseous phase. Furthermore, each exposure included a so-called clean air control, where cells where exposed to filtered air. The exposure was followed by a 21 h post-incubation before the cytotoxic effects were determined via LDH-release. To reveal if possible adverse effects are caused by the used nano-scaled filling material, all used nanomaterials did also undergo the same combustion process as a single material. Cytotoxicity studies showed no increased cytotoxic effects after the combustion of the sole nano-scaled filling materials. However, combustion of PE containing materials resulted in an enhanced LDH-release, and therefore cytotoxicity, in both cell culture models. Since no difference between exposures of unfiltered and filtered aerosols was apparent, it suggested that the observed cytotoxicity is due to the combustion induced gaseous phase.

O prolapso de vesícula urinária associado ao prolapso uterino é condição rara em cães e gatos. O tratamento preconizado para essa afecção é o reposicionamento anatômico das estruturas afetadas. No presente relato é descrito o manejo por meio de ovariossalpingo-histerectomia por celiotomia e, após dois dias, cistopexia videoassistida. Essa condição, conforme o conhecimento dos autores, não havia sido previamente descrita. A operação apresentou-se como possibilidade viável de tratamento, sem complicações pós-operatórias. The urinary bladder prolapse associated with the uterus is a rare condition on dogs and cats. The recommended treatment is the anatomical repositioning of the affected structures by manual reduction or surgery procedure. The present report describes the management by video-assisted cystopexy two days after conventional ovariohysterectomy. This condition, according to the authors' knowledge, had not been previously described. The operation didn't showed postoperative complications, and presented itself as a viable treatment option.

Einleitung: Die fetoskopische Trachealokklusion (FETO) gilt als aktueller Standard der pränatalen Behandlung einer schwergradigen angeborenen Zwerchfellhernie (CDH), ist aber nicht in der Lage den ursächlichen Schaden – den Druck des intrathorakalen Darmes auf die sich entwickelnde [for full text, please go to the a.m. URL], 132. Kongress der Deutschen Gesellschaft für Chirurgie

Background\ud \ud Ship engine emissions are important with regard to lung and cardiovascular diseases especially in coastal regions worldwide. Known cellular responses to combustion particles include oxidative stress and inflammatory signalling.\ud \ud Objectives\ud \ud To provide a molecular link between the chemical and physical characteristics of ship emission particles and the cellular responses they elicit and to identify potentially harmful fractions in shipping emission aerosols.\ud \ud Methods\ud \ud Through an air-liquid interface exposure system, we exposed human lung cells under realistic in vitro conditions to exhaust fumes from a ship engine running on either common heavy fuel oil (HFO) or cleaner-burning diesel fuel (DF). Advanced chemical analyses of the exhaust aerosols were combined with transcriptional, proteomic and metabolomic profiling including isotope labelling methods to characterise the lung cell responses.\ud \ud Results\ud \ud The HFO emissions contained high concentrations of toxic compounds such as metals and polycyclic aromatic hydrocarbon, and were higher in particle mass. These compounds were lower in DF emissions, which in turn had higher concentrations of elemental carbon (“soot”). Common cellular reactions included cellular stress responses and endocytosis. Reactions to HFO emissions were dominated by oxidative stress and inflammatory responses, whereas DF emissions induced generally a broader biological response than HFO emissions and affected essential cellular pathways such as energy metabolism, protein synthesis, and chromatin modification.\ud \ud Conclusions\ud \ud Despite a lower content of known toxic compounds, combustion particles from the clean shipping fuel DF influenced several essential pathways of lung cell metabolism more strongly than particles from the unrefined fuel HFO. This might be attributable to a higher soot content in DF. Thus the role of diesel soot, which is a known carcinogen in acute air pollution-induced health effects should be further investigated. For the use of HFO and DF we recommend a reduction of carbonaceous soot in the ship emissions by implementation of filtration devices.

We report the results of experiments and numerical calculations of compression and coalescence in a monodisperse oil-in-water emulsion upon centrifugation. A custom-built setup allows in-situ monitoring of a rotating bilayer of emulsion droplets using an optical microscope. The oil volume fraction in a compressed layer of oil droplets stabilized against coalescence was measured experimentally as a function of time for different radial accelerations. The sedimentation was simulated using CFD in order to test the applicability of the computationalmethod and the Ishii-Zuber drag law for very high dispersed phase volume fractions. Quantitative agreement of emulsion sedimentation as a function of time between the experiments and simulations is good at higher accelerations, but decreases with decreasing accelerations. Coalescence in a centrifuged emulsion, which was destabilized prior to centrifugation by adding sodium chloride, was also quantified. The growth of a pure oil phase on top of the droplet layer was measured as a function of time. From the growth rate, a characteristic time for droplet coalescence with the pure oil phase was deduced. The experimental method may serve as a tool to study the compression and coalescence kinetics of emulsions under enhanced gravity, which may be of use to assess emulsion stability for industrial applications. Possible improvements of the current experimental setup are also discussed.

The control of emulsion stability is of crucial importance in the process of crude/oil water separation, which is a key step in industrial oil production. Separation is enhanced if coalescence between droplets takes place, the extent of which will depend on the flow parameters as well as on the presence of emulsifying agents. Current theoretical models cannot satisfactorily predict the timescale of coalescence in flowing emulsions, especially when chemical additives, such as surfactants are present in the system. For that reason, a reliable and easy-to-use experimental method to assess crude-oil emulsion stability would be useful, but has not been available until now. In this work we present the results of microfluidic experiments on coalescence in an oil-in-water emulsion. Using a custom-designed microfluidic circuit, monodisperse droplets of a model oil in water formed at a microfluidic T-junction were injected into a wide channel where droplets are accumulated and undergo shear-induced collisions. The droplet interactions were followed with a microscope and a high-speed camera. The experimental method allows direct measurement of the kinetic parameters governing demulsification, which are the total coalescence rate of the emulsion and the distribution of individual coalescence times of colliding droplet pairs. The kinetic parameters were mapped as a function of the droplet size, fluid flow rates, electrolyte concentration and dispersed phase volume fraction and viscosity, respectively. All those measurements can be performed in a short time using a simple experimental setup. The proposed method is thus a useful tool to aid in the design or optimization of a separation process for a given produced crude oil/water mixture.

The stability of emulsions is an important factor for various industrial branches, such as the food, pharmaceutical and petroleum industries. For an improved prediction and control of emulsion stability it is necessary to understand the mechanism of droplet coalescence on a microscopic level. We use microfluidic methods to study the dynamics of coalescence in dense flowing or compressed emulsions, as these are often encountered in industrial applications.

Purpose Red blood cells (RBCs) express N-methyl D-aspartate (NMDA) receptors on their surface. We tested if NMDA receptor activation or inhibition had an influence on RBC deformability and aggregability. Methods Heparinized blood was drawn from healthy volunteers and centrifuged. RBCs were washed twice and resuspended with a hematocrit of 30% in a same buffer solution containing 3% dextran 70. Aliquots were prepared: a) control; b) containing 100 μM homocysteic acid (NMDA receptor agonist); c) 100 μM memantine (NMDA receptor inhibitor) and 100 μM homocysteic acid. RBC suspension viscometry (Contraves LS-30) was done at 37 °C with shear rates of 37.6 s(-1) and 0.1 s(-1). RBC aggregability was assessed with a Myrenne aggrometer and sedimentation rate. Results Neither NMDA receptor activation nor inhibition had an influence on biophysical properties of RBCs. RBC suspension viscosity at a shear rate of 37.6 s(-1) was 3.62 ± 0.16, 3.61 ± 0.13, and 3.62 ± 0.16 mPa.s for control, homocysteic acid, and memantine + homocysteic acid, respectively, indicating an unchanged RBC deformability. The RBC aggregability parameters (low shear viscosity, Myrenne aggregometry at stasis (M) and 3 s(-1) (M1), and the sedimentation rate) showed no influence of either memantine and/or homocysteic acid. A large interindividual variability in RBC aggregability was observed. A good correlation was found between M, M1 and sedimentation values, but not with low shear viscosity values. Conclusions An activation or inhibition of NMDA receptors on RBCs has no influence on their deformability and aggregability. RBC aggregability varies largely among individuals, which was consistently detected by the sedimentation rate and the Myrenne aggregometer, but not by low shear viscosity, which should not be used for this purpose.

The control of emulsion stability and droplet size is of crucial importance for oil production, especially for the processes of crude/oil water separation and cleanup of produced water. To recover pure oil and water, coalescence between droplets needs to take place, the extent of which will depend on the flow parameters as well as on the presence of emulsifying agents. For a successful separation, the demulsification time of the mixture must be smaller than its residence time in the separator. A direct measurement of the coalescence rate in dense flowing emulsions has not been achieved until now. In this work we present a microfluidic method that permits to assess the kinetic parameters governing coalescence in flowing emulsions. Monodisperse droplets of oil in water formed at a microfluidic T-junction were injected into a wide channel where droplets are accumulated to form a twodimensional emulsion layer (see figure). The droplets undergo collisions and coalesce. The coalescence process was followed with a microscope and a highspeed camera. Counting the number of coalescence events permits to calculate the coalescence rate and evolution of the droplet size distribution, which were mapped as a function of initial droplet size, flow rate and dispersed phase volume fraction. The results obtained provide information about the timescale of separation of the liquid mixture and may thus help in the design of the separation process for a given produced fluid.