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Introduction: Cardiopulmonary bypass is an essential component of cardiothoracic surgeries. However, significant complications such as systemic inflammatory response syndrome (SIRS) resulting from cardiopulmonary bypass (CPB) are a common occurrence due to contact between circulating blood and foreign surfaces that leads to platelet activation. It is suggested that different available CPB circuit coatings can potentially reduce platelet activation. However, there have been no published evidence-based reports confirming these claims. In addition, there is no well-established protocol for studying platelet activation biomarkers during CPB in vitro in a laboratory setting. Methods: CPB was simulated in the laboratory using bovine blood in two different types of coated CPB circuits: Trillium® Biosurface by Medtronic, and XcoatingTM Surface by Terumo. Fresh bovine blood samples were collected and circulated through the CPB circuit following the standard protocol used in the operation rooms. Blood samples were then collected at 5 min, 30 min, and 55 min during the circulation. Blood plasmas were separated and subjected to enzyme-linked immunosorbent assay to measure most established platelet activation markers P-selectin, Platelet Factor 4 (PF4), Glycoprotein IIb/IIIa (GPIIb/IIIa), and β-thromboglobulin (β-TG) at different time points. Results: The biomarker values at 30 min and 55 min were compared to the base values at 5 min for each type of CPB circuit. The results of the means from all measured biomarkers showed data measurements that indicated no significant variability within each coating. All collected data points fell within ±2 SD of the means, which was considered acceptable variations across technical replicates. Conclusion: In this study, we were able to establish an in vitro protocol in the laboratory setting that is precise and reliable with minimum intra-variability. This established protocol will allow for future studies in which different coated CPB circuits can be compared for their effectiveness in blocking platelet activation during the CPB.

This contribution discusses technical and growth relevant aspects of using laser techniques for weed control. The research on thermal weed control via laser first focused on the interaction of laser beams and weed plants. Due to preliminary studies, a CO2-laser was selected for further studies with regard to the process factors laser energy, laser spot area, coverage of the weeds meristem, weed species (Amaranthus retroflexus), and weed growth stage. Thereby, the laser damage was modeled in order to control the necessary laser output power online. Furthermore, the beam positioning leading to an effective damaging of the weeds was investigated and a test device was designed. With the aid of contemporary image processing algorithms for weed recognition and meristem determination, a laser and servo-motor control was developed. Most of the studies presented in this paper were part of the project “Investigations on laser light affected weed control of juvenile plants with the aid of image processing” funded by the Deutsche Forschungsgemeinschaft.

Capacitive extracellular stimulation is a common method in implanted stimulation electrodes. The basis for investigating the transmission of stimuli from an electrode to adhered cells are in vitro experiments using calcium imaging or patch clamp measurements. Computational spatial models are used to simulate the mechanism of signal transmission at the cell-electrode interface but require high computing power. In this work, the Stern model to characterize the electrochemical double-layer (EDL) formation and a modified two-domain model are combined into a holistic equivalent circuit modelling capacitive cell stimulation. The described parameters can be directly associated with physicochemical effects. A simulation of the involved control and measurement systems allows the validation of the model with in vitro patch clamp recordings. The relationship of the cell’s distance to the electrode and efficacy of signal transmission could be observed. With this concept we aim to convert different complex approaches into a simple model and thus give an overview of the mechanisms of stimulation. We want to facilitate the interpretation of measured signals especially in voltage clamp measurements.

Molecular structure engineering has proved to be an efficient strategy to modify the properties of photoactive materials for organic solar cells. Several studies focused on the halogenation of donor and acceptor molecules, in order to tune the energy levels, the absorption properties or the molecular packing of the materials. In particular, bromination of small-molecule acceptors increases the film crystallinity of the bulk heterojunction, leading to higher charge carrier mobilities, and therefore, to a more efficient charge transport. In this study, we synthesized a mono-brominated non-fullerene acceptor derived from end-group modification of the M3 acceptor. This material showed slightly higher energy levels than M3 and a higher π–π stacking distance due to the larger size of bromine atoms compared to the fluorine atoms in M3. In addition, a second acceptor with non-halogenated rhodanine-based end groups was synthesized and investigated. While solar cells based on the latter NFA only showed negligible efficiencies, solar cells fabricated with the mono-brominated acceptor C1 and the conjugated polymer PM6 revealed power conversion efficiencies up to 11.6%. [ABSTRACT FROM AUTHOR]

Background Pathophysiological changes in severely burned patients alter the pharmacokinetics (PK) of anti-infective agents, potentially leading to subtherapeutic concentrations at the target site. Albumin supplementation, to support fluid resuscitation, may affect pharmacokinetic properties by binding drugs. This study aimed to investigate the PK of piperacillin/tazobactam in burn patients admitted to the ICU before and after albumin substitution as total and unbound concentrations in plasma. Patients and methods Patients admitted to the ICU and scheduled for 4.5 g piperacillin/tazobactam administration and 200 mL of 20% albumin substitution as part of clinical routine were included. Patients underwent IV microdialysis, and simultaneous arterial plasma sampling, at baseline and multiple timepoints after drug administration. PK analysis of total and unbound drug concentrations under steady-state conditions was performed before and after albumin supplementation. Results A total of seven patients with second- to third-degree burns involving 20%–60% of the total body surface were enrolled. Mean (SD) AUC0–8 (h·mg/L) of total piperacillin/tazobactam before and after albumin substitution were 402.1 (242)/53.2 (27) and 521.8 (363)/59.7 (32), respectively. Unbound mean AUC0–8 before and after albumin supplementation were 398.9 (204)/54.5 (25) and 456.4 (439)/64.5 (82), respectively. Conclusions Albumin supplementation had little impact on the PK of piperacillin/tazobactam. After albumin supplementation, there was a numerical increase in mean AUC0–8 of total and unbound piperacillin/tazobactam, whereas similar C max values were observed. Future studies may investigate the effect of albumin supplementation on drugs with a higher plasma protein binding. [ABSTRACT FROM AUTHOR]

Background We previously reported excellent efficacy and improved safety aspects of rapid steroid withdrawal (RSWD) in the randomized controlled 1-year "Harmony" trial with 587 predominantly deceased-donor kidney transplant recipients randomized either to basiliximab or rabbit antithymocyte globulin induction therapy and compared with standard immunosuppressive therapy consisting of basiliximab, low tacrolimus once daily, mycophenolate mofetil and corticosteroids. Methods The 5-year post-trial follow-up (FU) data were obtained in an observational manner at a 3- and a 5-year visit only for those Harmony patients who consented to participate and covered clinical events that occurred from the second year onwards. Results Biopsy-proven acute rejection and death-censored graft loss rates remained low and independent of RSWD. Rapid steroid withdrawal was an independent positive factor for patient survival (adjusted hazard ratio 0.554, 95% confidence interval 0.314–0.976; P  = .041). The reduced incidence of post-transplantation diabetes mellitus in RSWD patients during the original 1-year study period was not compensated by later incidences during FU. Incidences of other important outcome parameters such as opportunistic infections, malignancies, cardiovascular morbidity/risk factors, donor-specific antibody formation or kidney function did not differ during FU period. Conclusions With all the limitations of a post-trial FU study, the Harmony FU data confirm excellent efficacy and beneficial safety aspects of RSWD under modern immunosuppressive therapy over the course of 5 years after kidney transplantation in an immunologically low-risk, elderly population of Caucasian kidney transplant recipients. Trial registration: Clinical trial registration number: Investigator Initiated Trial (NCT 00724022, FU study DRKS00005786) [ABSTRACT FROM AUTHOR]