36 research outputs found

    The Challenges of Identifying Significant Epistemic Failure in Science

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    If one follows the accounts by philosophers of science and the discussions in scientific communities, there can be little doubt that failure is an essential part of scientific practice. It is essential both in the sense of being integral to scientific practice and of being necessary for its overall success. Researchers who create new scientific knowledge face uncertainties about the nature of the problem they are trying to solve, the existence of a solution to that problem, the way in which a solution can be found, and their ability to find such a solution (Gläser, 2007, 247). The existence of these uncertainties means, in turn, that each research process carries the risk of failure

    A common approach for absolute quantification of short chain CoA thioesters in prokaryotic and eukaryotic microbes

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    Background Thioesters of coenzyme A participate in 5% of all enzymatic reactions. In microbial cell factories, they function as building blocks for products of recognized commercial value, including natural products such as polyketides, polyunsaturated fatty acids, biofuels, and biopolymers. A core spectrum of approximately 5–10 short chain thioesters is present in many microbes, as inferred from their genomic repertoire. The relevance of these metabolites explains the high interest to trace and quantify them in microbial cells. Results Here, we describe a common workflow for extraction and absolute quantification of short chain CoA thioesters in different gram-positive and gram-negative bacteria and eukaryotic yeast, i.e. Corynebacterium glutamicum, Streptomyces albus, Pseudomonas putida, and Yarrowia lipolytica. The approach assessed intracellular CoA thioesters down to the picomolar level and exhibited high precision and reproducibility for all microbes, as shown by principal component analysis. Furthermore, it provided interesting insights into microbial CoA metabolism. A succinyl-CoA synthase defective mutant of C. glutamicum exhibited an unaffected level of succinyl-CoA that indicated a complete compensation by the L-lysine pathway to bypass the disrupted TCA cycle. Methylmalonyl-CoA, an important building block of high-value polyketides, was identified as dominant CoA thioester in the actinomycete S. albus. The microbe revealed a more than 10,000-fold difference in the abundance of intracellular CoA thioesters. A recombinant strain of S. albus, which produced different derivatives of the antituberculosis polyketide pamamycin, revealed a significant depletion of CoA thioesters of the ethylmalonyl CoA pathway, influencing product level and spectrum. Conclusions The high relevance of short chain CoA thioesters to synthetize industrial products and the interesting insights gained from the examples shown in this work, suggest analyzing these metabolites in microbial cell factories more routinely than done so far. Due to its broad application range, the developed approach appears useful to be applied this purpose. Hereby, the possibility to use one single protocol promises to facilitate automatized efforts, which rely on standardized workflows

    Platelet-Released Growth Factors Induce Genes Involved in Extracellular Matrix Formation in Human Fibroblasts

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    Platelet concentrate products are increasingly used in many medical disciplines due to their regenerative properties. As they contain a variety of chemokines, cytokines, and growth factors, they are used to support the healing of chronic or complicated wounds. To date, underlying cellular mechanisms have been insufficiently investigated. Therefore, we analyzed the influence of Platelet-Released Growth Factors (PRGF) on human dermal fibroblasts. Whole transcriptome sequencing and gene ontology (GO) enrichment analysis of PRGF-treated fibroblasts revealed an induction of several genes involved in the formation of the extracellular matrix (ECM). Real-time PCR analyses of PRGF-treated fibroblasts and skin explants confirmed the induction of ECM-related genes, in particular transforming growth factor beta-induced protein (TGFBI), fibronectin 1 (FN1), matrix metalloproteinase-9 (MMP-9), transglutaminase 2 (TGM2), fermitin family member 1 (FERMT1), collagen type I alpha 1 (COL1A1), a disintegrin and metalloproteinase 19 (ADAM19), serpin family E member 1 (SERPINE1) and lysyl oxidase-like 3 (LOXL3). The induction of these genes was time-dependent and in part influenced by the epidermal growth factor receptor (EGFR). Moreover, PRGF induced migration and proliferation of the fibroblasts. Taken together, the observed effects of PRGF on human fibroblasts may contribute to the underlying mechanisms that support the beneficial wound-healing effects of thrombocyte concentrate products

    Rare and low-frequency exonic variants and gene-by-smoking interactions in pulmonary function

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    Genome-wide association studies have identified numerous common genetic variants associated with spirometric measures of pulmonary function, including forced expiratory volume in one second (FEV1), forced vital capacity, and their ratio. However, variants with lower minor allele frequencies are less explored. We conducted a large-scale gene-smoking interaction meta-analysis on exonic rare and low-frequency variants involving 44,429 individuals of European ancestry in the discovery stage and sought replication in the UK BiLEVE study with 45,133 European ancestry samples and UK Biobank study with 59,478 samples. We leveraged data on cigarette smoking, the major environmental risk factor for reduced lung function, by testing gene-by-smoking interaction effects only and simultaneously testing the genetic main effects and interaction effects. The most statistically significant signal that replicated was a previously reported low-frequency signal in GPR126, distinct from common variant associations in this gene. Although only nominal replication was obtained for a top rare variant signal rs142935352 in one of the two studies, interaction and joint tests for current smoking and PDE3B were s

    The clinical course of idiopathic pulmonary fibrosis and its association to quality of life over time: longitudinal data from the INSIGHTS-IPF registry

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    Background: Quality of life (QoL) is profoundly impaired in patients with idiopathic pulmonary fibrosis (IPF). However, data is limited regarding the course of QoL. We therefore analysed longitudinal data from the German INSIGHTS-IPF registry. Methods: Clinical status and QoL were assessed at enrollment and subsequently at 6- to 12-months intervals. A range of different QoL questionnaires including the St. George’s Respiratory Questionnaire (SGRQ) were used. Results: Data from 424 patients were included; 76.9% male; mean age 68.7 ± 9.1 years, mean FVC% predicted 75.9 ± 19.4, mean DLCO% predicted 36.1 ± 15.9. QoL worsened significantly during follow-up with higher total SGRQ scores (increased by 1.47 per year; 95% CI: 1.17 to 1.76; p < 0.001) and higher UCSD-SOBQ scores and lower EQ-5D VAS and WHO-5 scores. An absolute decline in FVC% predicted of > 10% was associated with a significant deterioration in SGRQ (increasing by 9.08 units; 95% CI: 2.48 to 15.67; p = 0.007), while patients with stable or improved FVC had no significantly change in SGRQ. Patients with a > 10% decrease of DLCO % predicted also had a significant increase in SGRQ (+ 7.79 units; 95% CI: 0.85 to 14.73; p = 0.028), while SQRQ was almost stable in patients with stable or improved DLCO. Patients who died had a significant greater increase in SGRQ total scores (mean 11.8 ± 18.6) at their last follow-up visit prior to death compared to survivors (mean 4.2 ± 18.9; HR = 1.03; 95% CI: 1.01 to 1.04; p < 0.001). All QoL scores across the follow-up period were significantly worse in hospitalised patients compared to non-hospitalised patients, with the worst scores reported in those hospitalised for acute exacerbations. Conclusions: QoL assessments in the INSIGHTS-IPF registry demonstrate a close relationship between QoL and clinically meaningful changes in lung function, comorbidities, disease duration and clinical course of IPF, including hospitalisation and mortality

    Health related quality of life in patients with idiopathic pulmonary fibrosis in clinical practice: insights-IPF registry

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    Background: The INSIGHTS-IPF registry provides one of the largest data sets of clinical data and self-reported patient related outcomes including health related quality of life (QoL) on patients with idiopathic pulmonary fibrosis (IPF). We aimed to describe associations of various QoL instruments between each other and with patient characteristics at baseline. Methods: Six hundred twenty-three IPF patients with available QoL data (St George's Respiratory Questionnaire SGRQ, UCSD Shortness-of-Breath Questionnaire SoB, EuroQol visual analogue scale and index EQ-5D, Well-being Index WHO-5) were analysed. Mean age was 69.6 +/- 8.7 years, 77% were males, mean disease duration 2.0 +/- 3.3 years, FVC pred was 67.5 +/- 17.8%, DLCO pred 35.6 +/- 17%. Results: Mean points were SGRQ total 48.3, UCSD SoB 47.8, EQ-5D VAS 66.8, and WHO-5 13.9. These instruments had a high or very high correlation (exception WHO-5 to EQ-5D VAS with moderate correlation). On bivariate analysis, QoL by SGRQ total was statistically significantly associated with clinical symptoms (NYHA;p < 0.001), number of comorbidities (p < 0.05), hospitalisation rate (p < 0.01) and disease severity (as measured by GAP score, CPI, FVC and 6-min walk test;p < 0.05 each). Multivariate analyses showed a significant association between QoL (by SGRQ total) and IPF duration, FVC, age, NYHA class and indication for long-term oxygen treatment. Conclusions: Overall, IPF patients under real-life conditions have lower QoL compared to those in clinical studies. There is a meaningful relationship between QoL and various patient characteristics

    Game laboratory studies

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    Prof. Dr. Jens Schröter ist Herausgeber der Reihe und die Herausgeber der einzelnen Hefte sind renommierte Wissenschaftler und -innen aus dem In- und Ausland.Um die Analyse von Computerspielen aus produktionsästhetischer Perspektive zu erproben, lehnt sich der vorliegende Band an die Akteur-Netzwerk-Theorie (ANT) an. Mit ihr geht es ihm um die Frage nach den Aktanten des Game Design – etwa: Welche Hard- und Softwarekomponenten kommen wann und wofür zum Einsatz; wie und mittels welcher Medien notieren Level-Designer ihre Ideen, und wie werden die Aufzeichnungen später von Programmierern implementiert; und welche Rolle spielt eigentlich eine Action-Figur auf dem Schreibtisch eines Textur-Artists

    Genetic landscape of congenital insensitivity to pain and hereditary sensory and autonomic neuropathies

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    Congenital insensitivity to pain (CIP) and hereditary sensory and autonomic neuropathies (HSAN) are clinically and genetically heterogeneous disorders exclusively or predominantly affecting the sensory and autonomic neurons. Due to the rarity of the diseases and findings based mainly on single case reports or small case series, knowledge about these disorders is limited. Here, we describe the molecular workup of a large international cohort of CIP/HSAN patients including patients from normally under-represented countries. We identify 80 previously unreported pathogenic or likely pathogenic variants in a total of 73 families in the >20 known CIP/HSAN-associated genes. The data expand the spectrum of disease-relevant alterations in CIP/HSAN, including novel variants in previously rarely recognized entities such as ATL3-, FLVCR1- and NGF-associated neuropathies and previously under-recognized mutation types such as larger deletions. In silico predictions, heterologous expression studies, segregation analyses and metabolic tests helped to overcome limitations of current variant classification schemes that often fail to categorize a variant as disease-related or benign. The study sheds light on the genetic causes and disease-relevant changes within individual genes in CIP/HSAN. This is becoming increasingly important with emerging clinical trials investigating subtype or gene-specific treatment strategies
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