Gravity has been a constant force throughout the Earth’s evolutionary history. Thus, one of the fundamental biological questions is if and how complex cellular and molecular functions of life on Earth require gravity. In this study, we investigated the influence of gravity on the oxidative burst reaction in macrophages, one of the key elements in innate immune response and cellular signaling. An important step is the production of superoxide by the NADPH oxidase, which is rapidly converted to H2O2 by spontaneous and enzymatic dismutation. The phagozytosis-mediated oxidative burst under altered gravity conditions was studied in NR8383 rat alveolar macrophages by means of a luminol assay. Ground-based experiments in “functional weightlessness” were performed using a 2 D clinostat combined with a photomultiplier (PMT clinostat). The same technical set-up was used during the 13th DLR and 51st ESA parabolic flight campaign. Furthermore, hypergravity conditions were provided by using the Multi-Sample Incubation Centrifuge (MuSIC) and the Short Arm Human Centrifuge (SAHC). The results demonstrate that release of reactive oxygen species (ROS) during the oxidative burst reaction depends greatly on gravity conditions. ROS release is 1.) reduced in microgravity, 2.) enhanced in hypergravity and 3.) responds rapidly and reversible to altered gravity within seconds. We substantiated the effect of altered gravity on oxidative burst reaction in two independent experimental systems, parabolic flights and 2D clinostat / centrifuge experiments. Furthermore, the results obtained in simulated microgravity (2D clinorotation experiments) were proven by experiments in real microgravity as in both cases a pronounced reduction in ROS was observed. Our experiments indicate that gravity-sensitive steps are located both in the initial activation pathways and in the final oxidative burst reaction itself, which could be explained by the role of cytoskeletal dynamics in the assembly and function of the NADPH oxidase complex.

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MIVS and conventional mitral valve surgery have a similar perioperative outcome. Mitral valve surgery via a right lateral minithoracotomy seems to be favorable with regard to resource-related outcome.

Background The current coronavirus disease 2019 (COVID‐19) pandemic has a huge impact on society and the economy and represents one of the biggest challenges for healthcare systems all over the world. Reports from healthcare institutions in different countries show a variety of crisis exit strategies. Methods The following is a review and update of the situation and crisis management in Zürich and Switzerland with a special focus on the impact on the cardiac surgery program and extracorporeal membrane oxygenation (ECMO)‐therapy in COVID‐19. Results Regional and national measures had avoided the collapse of the health system in Switzerland. There was a reduction of over 50% of the surgical and transcatheter caseload during the first wave of the pandemic. Twenty‐three ECMO devices, 150 oxygenators, and more than 300 different cannulas were at our disposal. Between March and May 2020, nine COVID‐19 patients were treated by us with ECMO‐therapy. Three patients were transported by us from distant institutions. Median age at ECMO implantation was 59 years. Two patients died on support. Conclusions Measures to prevent a collapse of the healthcare system were effective. Our local ECMO‐Program on the ongoing COVID‐19 pandemic has proven to be a useful tool to control mortality and organ failure in critically ill patients.

The first long-term follow-up after aortic root replacement with the Shelhigh® BioConduit revealed a relatively high rate of death and very high rate of reoperations due to endocarditis, aorto-ventricular disconnection and structural valve failure. This may be potentially connected to the nature of the implanted valved conduit.