557 research outputs found

    Part I: A novel in-vitro system for simultaneous mechanical stimulation and time-lapse microscopy in 3D

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    To investigate the migration response of cells to changes in their biophysical environment, a novel uniaxial cell stimulation device (UCSD) has been designed and tested. The device is capable of applying very precise user-defined static or dynamic mechanical stimuli in a physiologically relevant strain window (up to 50%) and frequency bandwidth (up to 2Hz) to cells residing in a three-dimensional (3D) environment while single-cell migration is simultaneously measured by time-lapse microscopy. The system is an advancement over uniaxial loading devices reported to date in that it allows temporal and spatial quantification of migration as a function of the micromechanical environment. We make use of the favorable physical and biological properties of poly(ethylene glycol) hydrogels as model matrix and present a method for fabricating cell-containing hydrogel constructs. The 3D strain field within these constructs is modeled by finite element analysis. Fibroblasts reversibly altered their morphology and orientation in response to the strain field. In the succeeding companion paper we then exploit the system to analyze fibroblast motility induced by different stimulation regimes (refer to part II

    Part II: Fibroblasts preferentially migrate in the direction of principal strain

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    A growing body of evidence suggests that the sensory information from the cytoskeleton and integrins may be responsible for guiding migration during mechano- and haptotaxis. However, the dual function of these subcellular structures as mechano-sensors and -actuators is only partially understood. Using a new cell chamber described in the preceding companion paper (Ref to part I, Raeber etal. 2007a) we investigated the migration response of adhesion-dependent fibroblasts embedded 3-dimensionally within synthetic protease-sensitive poly(ethylene glycol) hydrogels to stepwise and cyclic mechanical loads. To that end, we developed a spatially and temporally resolved migration analysis technique capable of providing estimates of statistical cell migration parameters along and perpendicular to the main strain direction. Fibroblasts reoriented themselves in the direction of principal strain, increased their proteolytic migration activity and moved preferentially parallel to the principal strain axis. These results point to a possible correlation between planes of iso-strain and migration directio

    A systematic review of interleukin-2-based immunotherapies in clinical trials for cancer and autoimmune diseases

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    BACKGROUND The cytokine interleukin-2 (IL-2) can stimulate both effector immune cells and regulatory T (Treg) cells. The ability of selectively engaging either of these effects has spurred interest in using IL-2 for immunotherapy of cancer and autoimmune diseases. Thus, numerous IL-2-based biologic agents with improved bias or delivery towards effector immune cells or Treg cells have been developed. This study systematically reviews clinical results of improved IL-2-based compounds. METHODS We searched the ClinicalTrials.gov database for registered trials using improved IL-2-based agents and different databases for available results of these studies. FINDINGS From 576 registered clinical trials we extracted 36 studies on different improved IL-2-based compounds. Adding another nine agents reported in recent literature reviews and based on our knowledge totalled in 45 compounds. A secondary search for registered clinical trials of each of these 45 compounds resulted in 141 clinical trials included in this review, with 41 trials reporting results. INTERPRETATION So far, none of the improved IL-2-based compounds has gained regulatory approval for the treatment of cancer or autoimmune diseases. NKTR-214 is the only compound completing phase 3 studies. The PIVOT IO-001 trial testing the combination of NKTR-214 plus Pembrolizumab compared to Pembrolizumab monotherapy in metastatic melanoma missed its primary endpoints. Also the PIVOT-09 study, combining NKTR-214 with Nivolumab compared to Sunitinib or Cabozantinib in advanced renal cell carcinoma, missed its primary endpoint. Trials in autoimmune diseases are currently in early stages, thus not allowing definite conclusions on efficacy. FUNDING This work was supported by public funding agencies

    Adaptive Immunosuppression in Lung Transplant Recipients Applying Complementary Biomarkers: The Zurich Protocol

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    Achieving adequate immunosuppression for lung transplant recipients in the first year after lung transplantation is a key challenge. Prophylaxis of allograft rejection must be balanced with the adverse events associated with immunosuppressive drugs, for example infection, renal failure, and diabetes. A triple immunosuppressive combination is standard, including a steroid, a calcineurin inhibitor, and an antiproliferative compound beginning with the highest levels of immunosuppression and a subsequent tapering of the dose, usually guided by therapeutic drug monitoring and considering clinical results, bronchoscopy sampling results, and additional biomarkers such as serum viral replication or donor-specific antibodies. Balancing the net immunosuppression level required to prevent rejection without overly increasing the risk of infection and other complications during the tapering phase is not well standardized and requires repeated assessments for dose-adjustments. In our adaptive immunosuppression approach, we additionally consider results from the white blood cell counts, in particular lymphocytes and eosinophils, as biomarkers for monitoring the level of immunosuppression and additionally use them as therapeutic targets to fine-tune the immunosuppressive strategy over time. The concept and its rationale are outlined, and areas of future research mentioned

    Easy and convenient millimole‐scale synthesis of new, potential biomarkers for gamma‐hydroxybutyric acid (GHB) intake: Feasible for analytical laboratories

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    New biomarkers indicating the abuse of drugs and alcohol are still of major interest for clinical and forensic sciences. The endogenous neurotransmitter and approved drug, gamma-hydroxybutyric acid (GHB), is often illegally used for drug-facilitated crimes by spiking GHB into alcoholic beverages. Analytical detection windows of only 6 h in blood and 12 h in urine are often too short to provide reliable proof of GHB ingestion. Therefore, new biomarkers are needed to prove exogenous GHB administration. Previously, amino acid GHB conjugates were discovered in an untargeted metabolomics screening and fatty acid esters with GHB were recently discussed as promising biomarkers to enlarge the analytical detection time windows. However, the development of analytical methods is still slowed down since reference compounds for targeted screenings are still missing. In this paper, we describe simple procedures for the rapid synthesis and purification of amino acid GHB conjugates as well as fatty acid esters, which can be adopted in analytical and clinical/forensic laboratories. Structural characterization data, together with IR, 1^1H-nuclear magnetic resonance (NMR), 13^{13}C-NMR, high-resolution mass spectra (MS), and MS/MS spectra in positive and negative ionization mode are reported for all obtained GHB conjugates and GHB conjugate precursors

    Schlussbericht und Handlungsempfehlungen zum Aufbau einer online Austauschplattform für Lehrpersonen

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    Der vorliegende Bericht fasst die Erkenntnisse des Projekts «Schweizweiter online Wissensaustausch unter Lehrpersonen» zusammen, welches von 2020-2023 durchgeführt wurde. In dem Projekt ging es um die Möglichkeit des Austausches von Unterrichtsmaterialien via Online-Plattform. Wir blicken zurück auf die unterschiedlichen Phasen des Projekts und die darin gewonnen Erkenntnisse. Mit einer Literaturrecherche und verschiedenen Befragungen wurden die Basis für das Projekt gelegt. Die Resultate flossen in die Evaluation und das Design einer möglichen Plattform ein. Anschliessend wurde eine Plattform aufgebaut, im August 2022 eingeführt und nach einem Jahr evaluiert. Mit den Erfahrungen aus den Literaturrecherchen, den diversen Erhebungen und der Einführung der Plattform formulieren wir am Schluss im Kapitel 6 vierzehn Handlungsempfehlungen für Schulen und Bildungseinrichtungen, welche eine Austauschplattform für Lehrpersonen in einer ähnlichen Art aufbauen und betreiben wollen

    Outcome of treatment of pulmonary tuberculosis in Switzerland in 1996.

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    Adequate treatment of pulmonary tuberculosis cures patients and reduces transmission. The study assesses treatment outcomes under current conditions in Switzerland. Retrospective cohort study including all TB cases with positive sputum cultures notified to the national surveillance system between July 1996 and June 1997. Ten months after notification, treating physicians reported the outcomes using WHO categories. Of 265 patients, 209 (79%) completed at least 6 months' treatment, 3 (1%) were treatment failures, 23 (9%) died, 8 (3%) defaulted from treatment and 22 (8%) left the country. The proportion of successful treatments did not significantly differ between the 103 Swiss-born (80%) and the 162 foreign-born (78%) patients. There were 19 deaths (18%) in the Swiss-born and 4 (2%) in the foreign-born groups; death was caused by TB in two patients, 10 died of other causes (cause unknown in 11). In the foreign-born group there were 31 (19%) potentially unsatisfactory outcomes (treatment failure, default from treatment, transfer abroad) and in the Swiss-born group 2 (2%). Default from treatment involved 8 patients, 6 of whom were asylum seekers. In a multivariate analysis potentially unsatisfactory outcomes were not significantly associated with foreign origin but with status as a foreigner of irregular or unknown legal status (adj. OR 8.8; 95% CI 1.4 to 53.7). Overall treatment success rates are satisfactory and similar to those of other western European countries. Potentially unsatisfactory outcomes are more common in foreign-born persons of irregular legal status. Tracking of non-adherent patients by health workers could further improve outcomes

    Coronary collateral perfusion in patients with coronary artery disease: effect of metoprolol

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    Background The use of ultrathin Doppler angioplasty guidewires has made it possible to measure collateral flow quantitatively. Pharmacologic interventions have been shown to influence collateral flow and, thus, to affect myocardial ischaemia. Methods Twenty-five patients with coronary artery disease undergoing PTCA were included in the present analysis. Coronary flow velocities were measured in the ipsilateral (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} n=25n=25 \end{document}) and contralateral (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} n=6n=6 \end{document}; two Doppler wires) vessels during PTCA with and without i.v. adenosine (140 μg/kg.min) before and 3 min after 5 mg metoprolol i.v., respectively. The ipsilateral Doppler wire was positioned distal to the stenosis, whereas the distal end of the contralateral wire was in an angiographically normal vessel. The flow signals of the ipsilateral wire were used to calculate the collateral flow index (CFI). CFI was defined as the ratio of flow velocity during balloon inflation divided by resting flow. Results Heart rate and mean aortic pressure decreased slightly (ns) after i.v. metoprolol. The collateral flow index was 0.25±0.12 (one fourth of the resting coronary flow) during the first PTCA and 0.27±0.14 (ns versus first PTCA) during the second PTCA, but decreased with metoprolol to 0.16±0.08 (\batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} p<0.0001p{<}0.0001 \end{document} vs. baseline) during the third PTCA. Conclusions Coronary collateral flow increased slightly but not significantly during maximal vasodilatation with adenosine but decreased in 23 of 25 patients after i.v. metoprolol. Thus, there is a reduction in coronary collateral flow with metoprolol, probably due to an increase in coronary collateral resistance or a reduction in oxygen deman
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