Einfluss der Cyclin-abhängigen Kinase 5 auf die Expression des Programmed Cell Death Ligand 1 in murinen Pankreaskarzinomen im Vergleich verschiedener Analysemethoden

Einleitung: Programmed Cell Death Ligand 1 (PD-L1) ist ein immuninhibitorisches Molekül, das für gewöhnlich von bestimmten Immunzellen oder dendritischen Zellen exprimiert wird. Auch verschiedene Tumoren exprimieren PD-L1, wodurch sie die antitumorale Immunabwehr unterwandern. Cyclin-abhängige Kinase 5 (CDK5) bildet eine atypische Cyclin-abhängige Kinase mit wichtigen Funktionen in Zellmigration und neuronaler Entwicklung. Dorand et al. (2016) wiesen eine CDK5-abhängige IFN-γ-vermittelte PD-L1-Hochregulation im Medulloblastom-Mausmodell nach. Dieser Mechanismus ist offenbar nicht Medulloblastom-spezifisch, da auch andere Tumoren und Zelltypen eine positive Korrelation von CDK5- und PD-L1-Expression zeigten. Methoden: Zur Evaluation von CDK5- und PD-L1-Expression kultivierten wir 7 verschiedene humane Zelllinien pankreatischer duktaler Adenokarzinome (PDAC) und generierten transgene Mauslinien der Genotypen LSL-KrasG12D; LSL-Trp53R172H; PDX1-Cre (KPC, CDK5 WT; n=18) sowie LSL-KrasG12D; LSL-Trp53R172H; PDX1-Cre; CDK5flox/flox (KPCC, CDK5 fl/fl; n=22), welche PDACs entwickelten. Mittels Western Blot erfolgte die Expressionsanalyse von CDK5 und PD-L1 in den PDAC-Zelllinien. Zur Analyse von CDK5- und PD-L1-Expression in vivo entnahmen wir das Pankreas der Mäuse und nutzten DAB-basierte Immunhistochemie zur Färbung der Präparate. In den Präparaten suchten wir die Bereiche mit der stärksten sowie schwächsten PD-L1-Intensität sowie 4 weitere zufällige Bereiche auf. Danach suchten wir die exakt korrespondierenden Regionen in den CDK5-Färbungen auf. Ergebnisse: Es zeigten sich statistisch signifikante Expressionsunterschiede zwischen den Mauspopulationen (KPC und KPCC) für CDK5 sowie für PD-L1 in der Immunhistochemie. Eine gesteigerte CDK5-Expression in der KPC-Mauspopulation (CDK5 WT) (84,40% vs. 13,07%, p<0,0001) war assoziiert mit höherer PD-L1-Expression verglichen mit der KPCC-Mauspopulation (CDK5 fl/fl) (83,56% vs. 51,96%, p<0,0001). Neben des höheren Prozentsatzes positiver Zellen für CDK5 und PD-L1 in der KPC-Gruppe zeigte sich zugleich auch eine stärkere Färbeintensität für beide Moleküle in dieser Gruppe. Desweiteren zeigte auch eine Expressionsanalyse mit dem Programm IHC Profiler statistisch signifikante Unterschiede zwischen beiden Gruppen. Diskussion: Die vorliegenden Daten stützen die Annahme, dass auch in PDACs eine höhere CDK5-Expression mit einer höheren und stärkeren Expression von PD-L1 einhergeht. Folglich kommen gegen PD-L1 bzw. dessen Rezeptor Programmed Cell Death Protein 1 (PD1) gerichtete Inhibitoren ebenso wie Inhibitoren des CDK5-Signalweges beim PDAC im Kontext einer Immuncheckpointtherapie als potentielle Therapeutika in Betracht.Influence of the Cyclin-Dependent Kinase 5 on the expression of Programmed Cell Death Ligand 1 in murine Pancreatic Carcinomas in comparison of different methods of analysis Introduction: Programmed Cell Death Ligand 1 (PD-L1) is an immune inhibitory molecule that usually is expressed by certain immune cells or dendritic cells. Also different tumor entities are expressing PD-L1, thus avoiding immune defense mechanisms. Cyclin dependent kinase 5 (CDK5) represents an atypical Cyclin dependent kinase, which has important functions in cell migration and neuronal development. Dorand et al. (2016) showed a CDK5-dependent IFN-γ-mediated PD-L1-upregulation in a Medulloblastoma mouse model. There are hints that this interaction is not just specific for Medulloblastomas. Also other tumors or cell types showed a positive correlation in CDK5 and PD-L1 expression. Methods: For evaluation of CDK5 and PD-L1 expression we cultured 7 different human cell lines of Pancreatic Ductal Adenocarcinomas (PDAC) and generated transgenic mouse lines with the genotypes LSL-KrasG12D; LSL-Trp53R172H; PDX1-Cre (KPC, CDK5 WT; n=18) and LSL-KrasG12D; LSL-Trp53R172H; PDX1-Cre; CDK5flox/flox (KPCC, CDK5 fl/fl; n=22), which developed PDACs due to their genetic mutations. We used Western Blot to compare the expression profiles of CDK5 and PD-L1 in the PDAC cell lines. To compare CDK5 and PD-L1 expression pattern in vivo we extracted the pancreas of the mice and used DAB-based immunohistochemistry (IHC) to stain the specimens. Then we searched for the areas in the specimens with the strongest and the lightest PD-L1 intensity, as well as for 4 random areas. In a second step we searched for the exactly corresponding regions in the slides stained for CDK5. Results: We found statistically significant different expression patterns between both mouse populations (KPC and KPCC) for CDK5 and also for PD-L1 using IHC. An increased CDK5 expression in the KPC mouse population (CDK5 WT) (84,40% vs. 13,07%, p<0,0001) was associated with a higher PD-L1 expression compared to the KPCC mice (CDK5 fl/fl) (83,56% vs. 51,96%, p<0,0001). Apart from higher percentages of positive cells for CDK5 and PD-L1 in the KPC group we could also demonstrate a stronger staining intensity in this group for both molecules. Further calculating the cell percentages stained with the program IHC Profiler also showed statistical significant differences between both groups. Discussion: The present data supports the assumption that also in PDACs higher CDK5 expression is associated with a higher and stronger expression of PD-L1. Thus PD-L1 inhibitors or inhibitors of its receptor Programmed Cell Death Protein 1 (PD1) as well as inhibitors of the CDK5 pathway could be a potential treatment in PDAC in the context of immune checkpoint therapy

Landscape quality payments in Switzerland : the congruence between policy and preferences

Peer reviewedPublisher PD

Momentum, Rather Than Velocity, Is a More Effective Measure of Improvements in Division IA Football Player Performance

Speed, or the time to complete straight runs or agility drills, is commonly used to assess performance in collegiate American football players. However, it is common for players\u27 speeds to plateau by the second year of eligibility, whereas their body masses continue to increase. The purpose of this study was to track change in speed, body mass, and momentum (body mass · velocity), across Division 1 football players\u27 4-year careers (n = 512). Complete data were derived for the 40-yd sprint (n = 82), the proagility shuttle (n = 73), and the L drill (n = 73) from the same NCAA Division 1 team over a 15-year period. Significant changes were seen for velocity between year 1 and the next 3 playing years (p \u3c 0.05), with no differences between years 2 and 4, whereas body mass increased significantly across all playing years (p \u3c 0.05). Further momentum increased across all years for all tests (p \u3c 0.0001). These results indicate the importance of including changes in body mass when evaluating performances during sprints and change of direction drills. Our results also suggest that using sprint or agility drill times to evaluate playing potential across football players\u27 collegiate careers may be ineffective and can provide players with a false and disheartening picture of their improvements across their careers. Momentum, which incorporates training-induced increases in both speed and body mass, would be a more relevant and supportive measure of players\u27 improvements. In addition, the simple computation of this variable, using existing speed and body mass data, may be an important addition to the National Football League combine as a measure of playing potential in the professional game

The Factory and the Beehive III: PTFEB132.707+19.810, a Low-Mass Eclipsing Binary in Praesepe Observed by PTF and K2

Theoretical models of stars constitute a fundamental bedrock upon which much of astrophysics is built, but large swaths of model parameter space remain uncalibrated by observations. The best calibrators are eclipsing binaries in clusters, allowing measurement of masses, radii, luminosities, and temperatures, for stars of known metallicity and age. We present the discovery and detailed characterization of PTFEB132.707+19.810, a P=6.0 day eclipsing binary in the Praesepe cluster ($\tau$~600--800 Myr; [Fe/H]=0.14$\pm$0.04). The system contains two late-type stars (SpT$_P$=M3.5$\pm$0.2; SpT$_S$=M4.3$\pm$0.7) with precise masses ($M_p=0.3953\pm0.0020$~$M_{\odot}$; $M_s=0.2098\pm0.0014$~$M_{\odot}$) and radii ($R_p=0.363\pm0.008$~$R_{\odot}$; $R_s=0.272\pm0.012$~$R_{\odot}$). Neither star meets the predictions of stellar evolutionary models. The primary has the expected radius, but is cooler and less luminous, while the secondary has the expected luminosity, but is cooler and substantially larger (by 20%). The system is not tidally locked or circularized. Exploiting a fortuitous 4:5 commensurability between $P_{orb}$ and $P_{rot,prim}$, we demonstrate that fitting errors from the unknown spot configuration only change the inferred radii by <1--2%. We also analyze subsets of data to test the robustness of radius measurements; the radius sum is more robust to systematic errors and preferable for model comparisons. We also test plausible changes in limb darkening, and find corresponding uncertainties of ~1%. Finally, we validate our pipeline using extant data for GU Boo, finding that our independent results match previous radii to within the mutual uncertainties (2--3%). We therefore suggest that the substantial discrepancies are astrophysical; since they are larger than for old field stars, they may be tied to the intermediate age of PTFEB132.707+19.810.Comment: Accepted to ApJ; 36 pages, 19 figures, 8 tables in two-column AASTEX6 forma

The structural biology of patellamide biosynthesis

This work was supported by grants from the ERC339367 (JHN and MJ) and BBSRCBB/K015508/1 (JHN and MJ).The biosynthetic pathways for patellamide and related natural products have recently been studied by structural biology. These pathways produce molecules that have a complex framework and exhibit a diverse array of activity due to the variability of the amino acids that are found in them. As these molecules are difficult to synthesize chemically, exploitation of their properties has been modest. The patellamide pathway involves amino acid heterocyclization, peptide cleavage, peptide macrocyclization, heterocycle oxidation and epimerization; closely related products are also prenylated. Enzyme activities have been identified for all these transformations except epimerization, which may be spontaneous. This review highlights the recent structural and mechanistic work on amino acid heterocyclization, peptide cleavage and peptide macrocyclization. This work should help in using the enzymes to produce novel analogs of the natural products enabling an exploitation of their properties.Peer reviewe

Using the Load-Velocity Profile for Predicting the 1RM of the Hexagonal Barbell Deadlift Exercise

Using the load-velocity profile for predicting the 1RM of the hexagonal barbell deadlift exercise. J Strength Cond Res 37(1): 220–223, 2023—The aim of this study was to determine whether bar velocity can be used to estimate the 1 repetition maximum (1RM) on the hexagonal bar deadlift (HBD). Twenty-two National Collegiate Athletic Association Division I male ice hockey players (age = 21.0 ± 1.5 years, height = 182.9 ± 7.3 cm, and body mass = 86.2 ± 7.3 kg) completed a progressive loading test using the HBD at maximum intended velocity to determine their 1RM. The mean concentric velocity was measured for each load through a linear position transducer. The a priori alpha level of significance was set at p = 0.05. The mean concentric velocity showed a very strong relationship to %1RM (R2 = 0.85). A nonsignificant difference and a trivial effect size (ES) were observed between the actual and predicted 1RM (p = 0.90, ES = −0.08). Near-perfect correlations were also discovered between the actual and predicted 1RM (R = 0.93) with low typical error and coefficient of variation (5.11 kg and 2.53%, respectively). This study presented results that add the HBD to the list of exercises with established load-velocity relationships. The predictive ability for 1RM HBD indicates that this is a viable means of prediction of 1RM

Modelling of Energy-Crops in Agricultural Sector Models - A Review of Existing Methodologies

The present report provides an overview of the different methodologies applied in partial and general equilibrium models used to analyse biofuel policies in Europe, as well as their methodological pros and cons. While the LEITAP model is included as a general equilibrium model covering biofuel demand, partial equilibrium models are represented by ESIM, FAPRI, AGLINK/COSIMO, RAUMIS, AGMEMOD (agricultural models); POLES and PRIMES (energy sector); and EUFASOM/ENFA (forestry sector). The study is highly relevant for the current modelling work at IPTS, where models such as ESIM and AGLINK play an important role in the Integrated Modelling Platform for Agro-economic Commodity and Policy Analysis (iMAP) of the AGRILIFE Unit. Additionally, the POLES model is currently part of the model portfolio used by the Competitiveness & Sustainability Unit in several studies analysing possible technological pathways of energy production and demand for bioenergy in Europe, a result of implementing the biofuel directive. This compilation of information is also important since the implicit and explicit treatment of bioenergy, either as a demand shock to the processing of oilseeds or feedstock for bioethanol and biodiesel, or as the introduction of a biofuel-sector into a computational general equilibrium (CGE) is foreseen in the short-term by other economic models used at IPTS.JRC.J.5-Agriculture and Life Sciences in the Econom

Structure of the cyanobactin oxidase ThcOx from Cyanothece sp. PCC 7425, the first structure to be solved at Diamond Light Source beamline I23 by means of S-SAD

Acknowledgements We thank Diamond Light Source for providing access to beamline I23. We also thank Thomas Sorensen and his staff for access to and support on beamline I02. This research was supported by grants from the UK Biotechnology and Biological Research Council (No. BB/K015508/1; JHN and MJ) and the European Research Council (No. 339367; JHN and MJ). Mass-spectrometric analysis was carried out by the Biomedical Sciences Research Complex Mass Spectrometry and Proteomics Facility, University of St Andrews and was funded by the Wellcome Trust (grant Nos. 094476/Z/10/Z and WT079272AIA). JHN is a Royal Society Wolfson Merit Award Holder and 1000 Talent scholar at Sichuan University.Peer reviewedPublisher PD