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Photodissociation of small group-14 atomic clusters in a multi-reflection time-of-flight mass spectrometer
Get PDFCationic and anionic clusters of the group-14 elements carbon, silicon, germanium, tin, and lead are produced by high-vacuum laser ablation and studied with a multi-reflection time-of-flight mass spectrometer. In-trap photodissociation is performed for cluster species in the size range n=2–10. The clusters’ production rates as well as their dissociation pathways are used to probe the nonmetal–metal transition throughout the group. Carbon clusters show neutral-trimer break-off, while those of the other elements evaporate neutral monomers and, in some cases, form specific charged fragment sizes
Health impact of borders: general reflections and a case study from the Polish–German border
Get PDFBackground and objective
Political, economic, communicative and cultural borders still limit the accessibility of acute healthcare services for patients so that they frequently have to accept longer distances to travel to the next provider within their own country. In this paper, we analyze the impact of borders and opening of borders on acute medical care in hospitals and on patients in border regions.
Methods
We develop a conceptual framework model of cross-border healthcare and apply it to the Polish–German border area. The model combines the distance decay effect, a catchment area analysis, economies of scale and the learning curve.
Results
Borders have a major impact on acute medical care in hospitals and on patients. Setting of new borders will reduce the accessibility of health facilities for patients or require the establishment of new hospitals. Reopening borders might induce a vicious circle leading to the insolvency of a hospital which might result in poorer health for some patients.
Conclusion
Strong effort should be invested to overcome political and cultural borders to improve the health of the population in border regions. Similarly, increased cross-border acute healthcare must be seen in the context of rural health and the special situation of small rural hospitals in rural peripheral areas
Zertifizierung der Deutschen Gesellschaft für Neurorehabilitation e. V., DGNR: Leistung und Qualität der „Zentren für Beatmungsentwöhnung in der neurologisch-neurochirurgischen Frührehabilitation“
Get PDFHintergrund
Die Zertifizierung von Zentren für Beatmungsentwöhnung in der neurologisch-neurochirurgischen Frührehabilitation (NNFR) durch die Deutsche Gesellschaft für Neurorehabilitation (DGNR) ist seit dem 01.10.2021 möglich.
Ziel der Arbeit
Die Ergebnisse der Zertifizierung von Einrichtungen im ersten Jahr nach Aufnahme des Verfahrens werden vorgestellt.
Material und Methoden
Im Rahmen der Zertifizierung werden 28 Kriterien geprüft, darunter eine Reihe mandatorisch zu erfüllender Charakteristika der Einrichtung. Die Kriterien gliedern sich in Strukturkriterien (i = 7), Diagnostikkriterien (i = 6), Personalkriterien (i = 3), Kriterien der internen Organisation (i = 7) und Qualitätsmanagementkriterien (i = 5).
Ergebnisse
Insgesamt 13 Zentren wurden im ersten Jahr zertifiziert, die zusammen über 283 Betten zur Beatmungsentwöhnung („weaning“) in der NNFR verfügen und im Jahr vor der Zertifizierung 2278 Personen im Weaning betreuten, im Median pro Einrichtung 134 (Bereich [Min-Max] 44–414). Nur selten war das Weaning nicht erfolgreich, sodass vor Entlassung auf eine Heimbeatmung eingestellt werden musste (invasive Heimbeatmung Median pro Einrichtung 10 Personen, Bereich 2–25; nichtinvasive Heimbeatmung Median 0 Personen, Bereich 0–57). Festgestellt wurde ein hohes Maß an Prozess- und Strukturqualität in den zertifizierten Zentren: Über alle Prüfbereiche hinweg waren die Prüfkriterien zu allermeist erfüllt (Median Erfüllungsgrad 86 %) bzw. erfüllt mit von den Auditor*innen dokumentierten Verbesserungspotenzialhinweisen (Median 11 %).
Schlussfolgerung
Erfolgreiches Weaning in der NNFR und ein hohes Maß an Prozess- und Strukturqualität lassen sich anhand der Zertifizierungsergebnisse der Zentren belegen, die diesen integrativen Ansatz bei der Beatmungsentwöhnung verfolgen.Background
Certification of centers for weaning from a ventilator in neurological neurosurgical early rehabilitation (NNER) by the German Society for Neurorehabilitation (DGNR) is possible since 1 October 2021.
Objective
The results of certification of facilities in the first year after starting the procedure are presented.
Material and methods
As part of the certification process 28 criteria are assessed including a set of mandatory characteristics of the facility. The criteria are divided into structural criteria (i = 7), diagnostic criteria (i = 6), personnel criteria (i = 3), internal organization criteria (i = 7), and quality management criteria (i = 5).
Results
A total of 13 centers were certified in the first year, with a combined total of 283 beds for weaning from a ventilator in the NNER and served 2278 persons to be weaned from a ventilator in the year before certification, with a median of 134 per facility (range 44–414). Only rarely was weaning unsuccessful, requiring conversion to home mechanical ventilation before discharge (invasive home mechanical ventilation median per facility 10 persons, range 2–25; non-invasive home mechanical ventilation median 0 persons, range 0–57). A high level of process and structural quality was documented for the certified centers: across all areas of assessment, the individual certification criteria were met in the vast majority of cases (median degree of complete fulfilment 86%) or met with improvement potentials documented by the auditors (median 11%).
Conclusion
Successful weaning in NNER and a high level of process and structural quality can be demonstrated by the certification results of centers that follow this integrative approach to weaning from a ventilator in a NNER setting
Changes in Genotype Composition and Morphology at an Experimental Site of Common Reed (Phragmites australis) Over a Quarter of a Century
Get PDFThe cultivation of common reed (Phragmites australis) is one of the most promising practices of paludiculture on fen peatlands. This highly productive grass has a high adaptation capacity via high levels of genetic diversity and phenotypic plasticity. In this study, a reed experimental site established on a degraded fen in 1996/97 with a mixture of monoclonally (meristematically propagated plantlets) and polyclonally (pre-grown seedlings) planted plots was investigated by microsatellite genotyping. All nine genotypes of the monoclonal planted plots were recovered and could be genetically characterized; invasion by other genotypes was negligible. Similarly, the polyclonal plots sustained high clonal diversity with no prevalence of a single genotype. The growth characteristics of the five quantitatively investigated genotypes significantly differed from each other (α = 0.05): dry biomass per stem 5–18 g, panicles per m2 20–60, average stem diameter 3.5–6 mm, height 170–250 cm. Similarly, the persistence of genotypes at the planted plots and their invasiveness (ability to invade neighboured plots) varied. These results show that common reed stands are extremely persistent even if established with genotypes that are likely not to be locally adapted. Their genetic structure remained stable for at least 24 years regardless of the planting density (1, 4, and 10 plants per m2). Our results indicate that farmers may be able to maintain favourable genotypes for many years, thus the selection and breeding of common reed as a versatile crop for rewetted peatlands is a promising objective for paludiculture research
Combined Blockade of TIGIT and PD-L1 Enhances Anti-Neuroblastoma Efficacy of GD2-Directed Immunotherapy with Dinutuximab Beta
Get PDFImmunotherapies against high-risk neuroblastoma (NB), using the anti-GD2 antibody (Ab) dinutuximab beta (DB), significantly improved patient survival. Ab-dependent cellular cytotoxicity (ADCC) is one of the main mechanisms of action and it is primarily mediated by NK cells. To further improve antitumor efficacy, we investigated here a combinatorial immunotherapy with DB and the double immune checkpoint blockade of T-cell immunoreceptor with immunoglobulin and ITIM domain (TIGIT) and programmed cell death ligand-1 (PD-L1). The effects of ADCC, mediated by DB against NB cells on NK-cell activity, and the expression of TIGIT and CD226 and their ligands CD112 and CD155, as well as of PD-1 and PD-L1 on NB and effector cells, were investigated using flow cytometry. ADCC was assessed with a calcein-AM-based cytotoxicity assay. The efficacy of a combinatorial immunotherapy with DB, given as a long-term treatment, and the double immune checkpoint blockade of TIGIT and PD-L1 was shown using a resistant murine model of NB, followed by an analysis of the tumor tissue. We detected both TIGIT ligands, CD112 and CD155, on all NB cell lines analyzed. Although ADCC by DB resulted in a strong activation of NK cells leading to an effective tumor cell lysis, a remarkable induction of PD-L1 expression on NB cells, and of TIGIT and PD-1 on effector cells, especially on NK cells, was observed. Additional anti-TIGIT or anti-PD-L1 treatments effectively inhibited tumor growth and improved survival of the mice treated with DB. The superior antitumor effects were observed in the “DB + double immune checkpoint blockade” group, showing an almost complete eradication of the tumors and the highest OS, even under resistant conditions. An analysis of tumor tissue revealed both TIGIT and TIGIT ligand expression on myeloid-derived suppressor cells (MDSCs), suggesting additional mechanisms of protumoral effects in NB. Our data show that the targeting of TIGIT and PD-L1 significantly improves the antitumor efficacy of anti-GD2 immunotherapy, with DB presenting a new effective combinatorial treatment strategy against high-risk tumors
Structure- and Data-Driven Protein Engineering of Transaminases for Improving Activity and Stereoselectivity
Get PDFAmine transaminases (ATAs) are powerful biocatalysts for the stereoselective synthesis of chiral amines. Machine learning provides a promising approach for protein engineering, but activity prediction models for ATAs remain elusive due to the difficulty of obtaining high-quality training data. Thus, we first created variants of the ATA from Ruegeria sp. (3FCR) with improved catalytic activity (up to 2000-fold) as well as reversed stereoselectivity by a structure-dependent rational design and collected a high-quality dataset in this process. Subsequently, we designed a modified one-hot code to describe steric and electronic effects of substrates and residues within ATAs. Finally, we built a gradient boosting regression tree predictor for catalytic activity and stereoselectivity, and applied this for the data-driven design of optimized variants which then showed improved activity (up to 3-fold compared to the best variants previously identified). We also demonstrated that the model can predict the catalytic activity for ATA variants of another origin by retraining with a small set of additional data
Closing the Gap: Towards a Fully Continuous and Self-Regulated Kolbe Electrosynthesis
Get PDFIn this article, we address the transition of the Kolbe electrolysis of valeric acid (VA) to n-octane as an exemplary electrosynthesis process from a batch reaction to a continuous, self-regulated process. Based on a systematic assessment of chemical boundary conditions and sustainability aspects, we propose a continuous electrosynthesis including a simple product separation and electrolyte recirculation, as well as an online-pH-controlled VA feeding. We demonstrate how essential performance parameters such as product selectivity (S) and coulombic efficiency (CE) are significantly improved by the transition from batch to a continuous process. Thus, the continuous and pH-controlled electrolysis of a 1 M valeric acid, starting pH 6.0, allowed a constantly high selectivity of around 47 % and an average Coulomb efficiency about 52 % throughout the entire experimental duration. Under otherwise identical conditions, the conventional batch operation suffered from lower and strongly decreasing performance values (Sn-octane, 60min=10.4 %, Sn-octane, 240min=1.3 %; CEn-octane, 60min=7.1 %, CEn-octane, 240min=0.5 %). At the same time, electrolyte recirculation significantly reduces wastes and limits the use of electrolyte components
Decreased inflammatory profile in oral leukoplakia tissue exposed to cold physical plasma ex vivo
Get PDFBackground
Oral leukoplakia (OL) is an unfavorable oral disease often resistant to therapy. To this end, cold physical plasma technology was explored as a novel therapeutic agent in an experimental setup.
Methods
Biopsies with a diameter of 3 mm were obtained from non-diseased and OL tissues. Subsequently, cold atmospheric pressure plasma (CAP) exposure was performed ex vivo in the laboratory. After 20 h of incubation, biopsies were cryo-conserved, and tissue sections were quantified for lymphocyte infiltrates, discriminating between naïve and memory cytotoxic and T-helper cells. In addition, the secretion pattern related to inflammation was investigated in the tissue culture supernatants by quantifying 10 chemokines and cytokines.
Results
In CAP-treated OL tissue, significantly decreased overall lymphocyte numbers were observed. In addition, reduced levels were observed when discriminating for the T-cell subpopulations but did not reach statistical significance. Moreover, CAP treatment significantly reduced levels of C-X-C motif chemokine 10 (CXCL10) and granulocyte-macrophage colony-stimulating factor in the OL biopsies' supernatants. In idiopathically inflamed tissues, ex vivo CAP exposure reduced T-cells and CXCL10 as well but also led to markedly increased interleukin-1β secretion.
Conclusion
Our findings suggest CAP to have immuno-modulatory properties, which could be of therapeutic significance in the therapy of OL. Future studies should investigate the efficacy of CAP therapy in vivo in a larger cohort
Dust acoustic wave properties in varying discharge volumes
Get PDFProperties of self-excited dust acoustic waves under the influence of active compression of the dust particle system were experimentally studied in the laboratory and under microgravity conditions (parabolic flight). Ground based laboratory experiments clearly show that wave properties can be manipulated by changing the discharge volume, its aspect ratio, and thus the dust particle density. Complementary experiments under microgravity conditions, performed to exclude the effects of gravity inflicted sedimentation and anisotropic behavior, were less conclusive due to residual fluctuations in the planes acceleration indicating the need for a better microgravity environment. A theoretical model, using plasma parameters obtained from particle-in-cell simulations as input, supports the experimental findings. It shows that the waves can be described as a new observation of the dust acoustic mode, which demonstrates their generic character
Funktionelle Untersuchungen zu OCTN2 und L-Carnitin assoziierten Effekten im Glioblastom und deren pharmakologische Beeinflussung im Tiermodell
Get PDFDas Glioblastom ist ein hochmaligner und aggressiver Hirntumor, der von der WHO als Grad IV eingestuft wird. Die Betroffenen haben eine mittlere Überlebenszeit von 12 bis 15 Monaten, was auf dem invasiven Wachstum und der Chemo- und Radioresistenz des Tumors beruht. Dadurch existiert keine kurative Behandlung und es kommt in nahezu allen Fällen zu Rezidiven. Zunehmend wird deutlich, dass das Glioblastom einen stark veränderten Energiestoffwechsel aufweist, wobei das sogenannte lipidomic remodelling (Koundouros und Poulogiannis, 2020), welches für maßgebliche Alterationen im Fettsäuremetabolismus sorgt, besonders interessant erscheint. Die Fettsäureoxidation sowie damit assoziierte Prozesse und Proteine sind als eine bedeutende Energiequelle in den Fokus der Forschung getreten. So auch der hoch-affine Carnitintransporter OCTN2 (SLC22A5), welcher essentiell für den Carnitinhaushalt und damit die β-Oxidation der Zelle ist. In der vorgelegten Arbeit wurde daher das komplexe OCTN2/L-Carnitin System in seiner Funktion als potenzielle pharmakologische Zielstruktur zur therapeutischen Intervention beim Glioblastom tiefergehend untersucht und vorhandenes Wissen weiter ausgebaut. Hierzu diente eine Vielzahl experimenteller Bedingungen und Methoden, um Teilcharakteristiken des Glioblastoms darzustellen und die Bedeutung des OCTN2/L-Carnitin System zu überprüfen.
Da in vorausgegangenen Studien eine erhöhte Expression von OCTN2 mit einem signifikant schlechteren Überleben von Patienten mit Glioblastom nachgewiesen werden konnte, wurden als weitere potentiell interessante Zielstrukturen der niedrig-affine Carnitintransporter OCTN1 (SLC22A4) sowie Komponenten der β-Oxidation (CPT1C, CRAT) in die Patientenanalysen eingeschlossen. Zwar konnte für OCTN1 eine signifikant erhöhte mRNA-Expression in den humanen Glioblastomproben festgestellt werden, diese war jedoch nicht mit dem Überleben der Patienten assoziiert. Auch CPT1C und CRAT zeigten sich nicht als relevante Zielstrukturen beim Glioblastom.
In den durchgeführten Zellkulturexperimenten mit humanen LN-18 und murinen GL261 Glioblastomzellen zeigten sich partiell signifikante Effekte auf die wachstumsfördernden Kinasen AKT1 und ERK1/2, deren Phosphorylierungsgrad durch L-Carnitin moduliert wurde und die damit möglicherweise an carnitinvermittelten Wirkungen beteiligt sein könnten. Auf die Zellviabilität und Zellvitalität ließen sich hemmende Wirkungen des OCTN2-Inhibitors Meldonium sowie des CPT1-Hemmstoffes Etomoxir nachweisen, welche teilweise durch die zusätzliche Gabe von L-Carnitin revertiert wurden. Hinsichtlich der durch Zytostatika (Doxorubicin, Carmustin, Vincristin und Temozolomid) induzierten Apoptose konnte L-Carnitin nur die durch Carmustin in niedriger Dosierung ausgelöste Caspase-3 Aktivierung verhindern. Ein durch L-Carnitin ausgelöster Effekt auf die Migration der Glioblastomzellen konnte nicht nachgewiesen werden, jedoch wurde die migratorische Aktivität durch die Zytostatika Temozolomid und Carmustin, sowie interessanterweise auch durch den CPT1-Inhibitor Etomoxir, beeinträchtigt.
Um die Möglichkeit einer zielgerichteten Therapie gegen das OCTN2/L-Carnitin System präklinisch zu evaluieren, wurden tierexperimentelle Studien durchgeführt. Unter Verwendung eines orthotopen Glioblastommodelles der Maus konnte gezeigt werden, dass Etomoxir und Meldonium einen hemmenden Einfluss auf das in vivo Tumorwachstum besitzen, wobei dieser Effekt nur für den OCTN2-Inhibitor Meldonium signifikant ausfiel. In den OCTN2-defizienten jvs(-/-)-Mäusen konnte keine ausreichende Anzahl von Versuchstieren erreicht werden, um zuverlässige und finale Aussagen zu tätigen. In den heterozygoten jvs(+/-)-Mäusen, die zwar phänotypisch unauffällig sind, aber durch die geringere OCTN2 Ausstattung verminderte Carnitin-Gewebespiegel aufweisen, zeigte sich eine leichte, nicht signifikante Reduktion des intrazerebralen Tumorwachstums im Vergleich zu den C57BL/6-Wildtyp Mäusen.
Zusammenfassend wurde in der vorliegenden Arbeit das OCTN2/L-Carnitin System und seine Bedeutung für das Glioblastom umfassend dargelegt und experimentell überprüft. Als Endresultat dieser Studie können Etomoxir und Meldonium als Substanzen zur zielgerichteten Beeinflussung des Glioblastomwachstums angesehen werden und sollten in weiteren Versuchsreihen detailliert auf ihre Eignung für die Entwicklung neuer Therapieformen überprüft werden