VEGF- und Kollagenbildung von Meniskuszellreihen und mesenchymalen Stammzellen alleine sowie im Zusammenspiel mit Gelatine-Hyaluronsäurematrices zur Reparatur avaskulärer Meniskusläsionen

Avaskuläre Meniskusläsionen stellen aufgrund eines fehlenden endogenen Reparaturpotentials ein Problem dar, da die Standardtherapie der partiellen Meniskektomie in diesen Fällen langfristig zu einer Gonarthrose führt. Zur Ausheilung des Defektes könnte Tissue Engineering, bei dem ein in vitro hergestelltes Reparaturgewebe in den Defekt eingebracht wird, die Lösung des Problems darstellen. Ziel der Arbeit war es, herauszufinden, welches angiogenetische Milieu von Meniskuszellen und von mesenchymalen Stammzellen in Bezug auf VEGF geschaffen wird und wie die jeweilige Differenzierung sowie die Kollagen-I und -II-Bildung ist. Alle Arbeiten wurden in vitro durchgeführt. Zunächst war zu prüfen, ob weiterführende Forschungsarbeiten anstelle von humanen Zellen mit Kaninchenzellen durchgeführt werden können. Untersuchte Zellen waren jeweils Meniskuszellen aus der vaskulären, der avaskulären, der gemischtvaskulären Zone und mesenchymale Stammzellen. Es wurden Aggregate dieser Zelllinien hergestellt und eine anschließende 21-tägige Differenzierung durchgeführt. Humane und Kaninchenzelllinien verhielten sich in Bezug auf Größenzunahme und Differenzierung vergleichbar, Kollagen II wurde in humanen Zellaggregaten nur in gemischtvaskulären Meniskuszellaggregaten und mesenchymalen Stammzellaggregaten gebildet, bei Kaninchenzellaggregaten in allen Zelllinien. Bezüglich der VEGF-Produktion zeigten gemischtvaskuläre Meniskuszellaggregate und mesenchymale Stammzellaggregate vom Menschen und vom Kaninchen ähnliche Ergebnisse, weitere Untersuchungen wurden als reines Tierexperiment durchgeführt. Nach Beimpfen von Gelatine-Hyaluronsäure-Matrices mit Kaninchenzelllinien wurden diese Zell-Matrix-Konstrukte bezüglich einer 14-tägigen Vorkultur vor der 21-tägigen Differenzierungszeit unterschieden. Eine Vorkultur hatte einen positiven Einfluss auf die Kollagen-Bildung und auf die Differenzierung, Kollagen-II wurde von mesenchymalen Stammzellen in einer Gelatine-Hyaluronsäure-Matrix nicht gebildet. Die Gelatine-Hyaluronsäurematrix zeigte einen hemmenden Einfluss auf die VEGF-Produktion. Ein Abfall der VEGF-Produktion während der Differenzierungszeit war bei allen Zelllinien mit als auch ohne Vorkultur auszumachen. Ohne Vorkultur wurde mehr VEGF produziert. Schließlich wurden die mit unterschiedlichen Zelllinien beimpften und in Vorkultur unterschiedenen Gelatine-Hyaluronsäure-Matrices in vitro in avaskuläre/gemischtvaskuläre Meniskusdefekte eingebracht, bevor eine 21-tägige Differenzierung durchgeführt wurde. Eine Vorkultur der Zell-Matrix-Konstrukte hatte einen positiven Einfluss auf die Integration in den Meniskusdefekt, die Differenzierung und die Kollagenbildung. Mesenchymale Stammzell-Matrix-Konstrukte zeigten im Meniskusdefekt wieder eine Kollagen-II-Bildung. Auch Leermatrices zeigten eine Integration in den Meniskusdefekt mit Kollagenbildung beider untersuchten Typen. Bei der VEGF-Produktion zeigte sich, dass ein Meniskusring alleine als auch mit zellfreier Gelatine-Hyaluronsäurematrix auf stabilem Niveau VEGF produzierte. Zell-Matrix-Konstrukte ohne Vorkultur produzierten im Meniskusdefekt mehr VEGF als mit einer Vorkultur. Ohne Vorkultur zeigten Meniskuszell-Matrix-Konstrukte im Meniskusdefekt eine abfallende VEGF-Produktion während der Differenzierung, mesenchymale Stammzell-Matrix-Konstrukte im Meniskusdefekt eine konstante VEGF-Produktion. Mit Vorkultur zeigten vaskuläre und avaskuläre Meniskuszell-Matrix-Konstrukte eine konstante VEGF-Produktion im Meniskusdefekt während der Differenzierungszeit, gemischtvaskuläre Meniskuszell-Matrix-Konstrukte und mesenchymale Stammzell-Matrix-Konstrukte eine leicht steigende Produktion

Augmented Air Traffic Control System—Artificial Intelligence as Digital Assistance System to Predict Air Traffic Conflicts

Today’s air traffic management (ATM) system evolves around the air traffic controllers and pilots. This human-centered design made air traffic remarkably safe in the past. However, with the increase in flights and the variety of aircraft using European airspace, it is reaching its limits. It poses significant problems such as congestion, deterioration of flight safety, greater costs, more delays, and higher emissions. Transforming the ATM into the “next generation” requires complex human-integrated systems that provide better abstraction of airspace and create situational awareness, as described in the literature for this problem. This paper makes the following contributions: (a) It outlines the complexity of the problem. (b) It introduces a digital assistance system to detect conflicts in air traffic by systematically analyzing aircraft surveillance data to provide air traffic controllers with better situational awareness. For this purpose, long short-term memory (LSTMs) networks, which are a popular version of recurrent neural networks (RNNs) are used to determine whether their temporal dynamic behavior is capable of reliably monitoring air traffic and classifying error patterns. (c) Large-scale, realistic air traffic models with several thousand flights containing air traffic conflicts are used to create a parameterized airspace abstraction to train several variations of LSTM networks. The applied networks are based on a 20–10–1 architecture while using leaky ReLU and sigmoid activation function. For the learning process, the binary cross-entropy loss function and the adaptive moment estimation (ADAM) optimizer are applied with different learning rates and batch sizes over ten epochs. (d) Numerical results and achievements by using LSTM networks to predict various weather events, cyberattacks, emergency situations and human factors are presented

Effect Sizes in Experimental Pain Produced by Gender, Genetic Variants and Sensitization Procedures

Background: Various effects on pain have been reported with respect to their statistical significance, but a standardized measure of effect size has been rarely added. Such a measure would ease comparison of the magnitude of the effects across studies, for example the effect of gender on heat pain with the effect of a genetic variant on pressure pain. Methodology/Principal Findings: Effect sizes on pain thresholds to stimuli consisting of heat, cold, blunt pressure, punctuate pressure and electrical current, administered to 125 subjects, were analyzed for 29 common variants in eight human genes reportedly modulating pain, gender and sensitization procedures using capsaicin or menthol. The genotype explained 0–5.9% of the total interindividual variance in pain thresholds to various stimuli and produced mainly small effects (Cohen's d 0–1.8). The largest effect had the TRPA1 rs13255063T/rs11988795G haplotype explaining >5% of the variance in electrical pain thresholds and conferring lower pain sensitivity to homozygous carriers. Gender produced larger effect sizes than most variant alleles (1–14.8% explained variance, Cohen's d 0.2–0.8), with higher pain sensitivity in women than in men. Sensitization by capsaicin or menthol explained up to 63% of the total variance (4.7–62.8%) and produced largest effects according to Cohen's d (0.4–2.6), especially heat sensitization by capsaicin (Cohen's d = 2.6). Conclusions: Sensitization, gender and genetic variants produce effects on pain in the mentioned order of effect sizes. The present report may provide a basis for comparative discussions of factors influencing pain

Effect sizes, expressed as percentage of the total variance explained by the respective factor, on pain thresholds.

#<p>MAF: Observed minor allelic frequencies. “Minor” refers to the allele reported to be minor in gene databases. When its reported allelic frequency is close to 50%, it can happen that the “minor” allele has a frequency >50% in the actual cohort. We nevertheless preserved the denomination “minor” to be consistent with SNP databases.</p><p>In the case of the genetic factors, the reference and the observed allelic frequencies are given, and the dominant hereditary model was used, i.e., assigning heterozygous subjects to the group of wild-type carriers. The effect sizes are given in italic letters when they were larger than those of gender, and in bold letters when exceeding, arbitrarily chosen, 5%.</p

Effect sizes, expressed as absolute values of Cohen's d [15], of the respective factor on pain thresholds.

<p>In the case of the genetic factors, the dominant hereditary model was used, i.e., assigning heterozygous subjects to the group of wild-type subjects. The effect sizes are given in italic letters when they were larger than those of gender, and in bold letters when exceeding a value of 0.8 indicating a large effect.</p

Effect sizes, expressed as percentage of the total variance explained by the genetic factors, on pain thresholds.

#<p>MAF: Observed minor allelic frequencies. “Minor” refers to the allele reported to be minor in gene databases. When its reported allelic frequency is close to 50%, it can happen that the “minor” allele has a frequency >50% in the actual cohort. We nevertheless preserved the denomination “minor” to be consistent with SNP databases.</p><p>The reference and the observed allelic frequencies are given, and the recessive hereditary model was used, i.e., assigning heterozygous subjects to the group of homozygous mutated carriers. The effect sizes are given in italic letters when they were larger than those of gender, and in bold letters when exceeding, arbitrarily chosen, 5%.</p

Effect sizes, expressed as absolute values of Cohen's d [15], of the genetics factors on pain thresholds.

<p>The recessive hereditary model was used, i.e., assigning heterozygous subjects to the group of homozygous mutated carriers. The effect sizes are given in italic letters when they were larger than those of gender, and in bold letters when exceeding a value of 0.8 indicating a large effect.</p

Observed thresholds to different pain stimuli and sizes of modulatory effects.

<p><b>Left</b> part: Single values of the measured pain thresholds to various stimuli are shown as dots, with statistical summaries in overlaid box plots. The boxes span the 25^th to 75^th percentiles, with the median crossing the box as a horizontal line, and the whiskers spanning values within 1.5 times the 25^th to 75^th percentiles. The subject's gender is indicated by different symbols and colors (men: red circles, women: blue crosses). At the <b>right</b> of each thresholds presentation, the effect sizes of the genetic variants obtained using the dominant hereditary model (blue filled circles), i.e., heterozygous and homozygous carriers of the variant alleles versus wild type subjects, and the recessive model (red empty circles), i.e., homozygous carriers of the variant versus the other subjects, are shown as correlation plots between the fraction of the total variance in the respective threshold explained by the respective factor and Cohen's d of that factor. An absolute value of d = 0.2 indicates a small effect, values around 0.5 a medium and above 0.8 a large effect <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0017724#pone.0017724-Cohen1" target="_blank">[15]</a>. In addition, the effects sizes of gender (green filled triangles) and sensitization (orange filled squares) by capsaicin (heat, von Frey hair punctate pressure) or menthol (cold) are shown. Note that the axis scaling is non-uniform among panels to enhance data visibility. At the bottom, the overall effect sizes (all Cohen's d per condition genetics, gender or sensitization) of all analyzed factors and stimuli are grouped for genetic, gender and sensitization influences on pain thresholds, showing decreasing sizes of effects in the order sensitization, gender and genetics.</p