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Background: Outcomes of catheter ablation of atrial fibrillation (AF) are variable and the predictors of success require further elucidation since the identification of correctable risk factors could help to optimize therapy. We aimed to assess the impact of body mass index (BMI) in the overall safety and efficacy of catheter ablation of AF, with emphasis on the use of cryoballoon ablation and novel oral anticoagulants.
Methods and Results: There were 2497 consecutive patients undergoing catheter ablation of AF in 7 European high volume centers were stratified according to BMI (normal weight <25 kg/m2, pre‐obese 25–30 kg/m2, obesity 30–35 kg/m2, and morbid obesity ≥35 kg/m2) and comparisons of procedural outcomes evaluated. Pre‐obese and obese patients presented more comorbidities (hypertension, diabetes mellitus, and sleep apnea), and had higher rates of non‐paroxysmal AF ablation procedures. The rate of atrial 12‐month arrhythmia relapse increased alongside with BMI (35.2%, 35.7%, 43.6%, and 48.0% P<0.001). During a median follow‐up of 18.8 months (interquartile range 11–28), after adjusting for all baseline differences, BMI was an independent predictor of relapse (hazard ratio=1.01 per kg/m2; 95% CI 1.01–1.02; P=0.002), adding incremental predictive value to obstructive sleep apnea. BMI was not a predictor for any of the reported complications. Using novel oral anticoagulants and cryoballoon ablation was safe and efficacy was comparable with vitamin‐K antagonists and radiofrequency ablation.
Conclusions: Obese patients present with a more adverse comorbidity profile, more advanced forms of AF, and have lower chances of being free from AF relapse after ablation. Use of novel oral anticoagulants and cryoballoon ablation may be an option in this patient group.
In vivo functional diversity of midbrain dopamine neurons within identified axonal projections
(2019)
Functional diversity of midbrain dopamine (DA) neurons ranges across multiple scales, from differences in intrinsic properties and connectivity to selective task engagement in behaving animals. Distinct in vitro biophysical features of DA neurons have been associated with different axonal projection targets. However, it is unknown how this translates to different firing patterns of projection-defined DA subpopulations in the intact brain. We combined retrograde tracing with single-unit recording and labelling in mouse brain to create an in vivo functional topography of the midbrain DA system. We identified differences in burst firing among DA neurons projecting to dorsolateral striatum. Bursting also differentiated DA neurons in the medial substantia nigra (SN) projecting either to dorsal or ventral striatum. We found differences in mean firing rates and pause durations among ventral tegmental area (VTA) DA neurons projecting to lateral or medial shell of nucleus accumbens. Our data establishes a high-resolution functional in vivo landscape of midbrain DA neurons.
Intact-cell maldi-tof mass spectrometry for the authentication of drug-adapted cancer cell lines
(2019)
The use of cell lines in research can be affected by cell line misidentification. Short tandem repeat (STR) analysis is an effective method, and the gold standard, for the identification of the genetic origin of a cell line, but methods that allow the discrimination between cell lines of the same genetic origin are lacking. Here, we use intact cell MALDI-ToF mass spectrometry analysis, routinely used for the identification of bacteria in clinical diagnostic procedures, for the authentication of a set of cell lines consisting of three parental neuroblastoma cell lines (IMR-5, IMR-32 and UKF-NB-3) and eleven drug-adapted sublines. Principal component analysis (PCA) of intact-cell MALDI-ToF mass spectrometry data revealed clear differences between most, but not all, of the investigated cell lines. Mass spectrometry whole-cell fingerprints enabled the separation of IMR-32 and its clonal subline IMR-5. Sublines that had been adapted to closely related drugs, for example, the cisplatin- and oxaliplatin-resistant UKF-NB-3 sublines and the vincristine- and vinblastine-adapted IMR-5 sublines, also displayed clearly distinctive patterns. In conclusion, intact whole-cell MALDI-ToF mass spectrometry has the potential to be further developed into an authentication method for mammalian cells of a common genetic origin.
Anaplastic large cell lymphoma (ALCL) and classical Hodgkin lymphoma (cHL) are lymphomas that contain CD30-expressing tumor cells and have numerous pathological similarities. Whereas ALCL is usually diagnosed at an advanced stage, cHL more frequently presents with localized disease. The aim of the present study was to elucidate the mechanisms underlying the different clinical presentation of ALCL and cHL. Chemokine and chemokine receptor expression were similar in primary ALCL and cHL cases apart from the known overexpression of the chemokines CCL17 and CCL22 in the Hodgkin and Reed-Sternberg (HRS) cells of cHL. Consistent with the overexpression of these chemokines, primary cHL cases encountered a significantly denser T cell microenvironment than ALCL. Additionally to differences in the interaction with their microenvironment, cHL cell lines presented a lower and less efficient intrinsic cell motility than ALCL cell lines, as assessed by time-lapse microscopy in a collagen gel and transwell migration assays. We thus propose that the combination of impaired basal cell motility and differences in the interaction with the microenvironment hamper the dissemination of HRS cells in cHL when compared with the tumor cells of ALCL.
Inflammatory activation of astroglia adds to the pathology of various neurological diseases. Astrocytes respond to microglia-derived cytokines such as interleukin-1α (IL-1α) with enhanced inflammatory signaling. This provokes pro-inflammatory gene expression of, among others, the eicosanoid-generating enzyme prostaglandin endoperoxide synthase 2 (Ptgs2). Whereas metabolic regulation of innate immune cell inflammatory responses is intensely studied, pathways related to how metabolism modulates inflammatory signaling in astrocytes are underexplored. Here, we examined how mitochondrial oxidative phosphorylation affects inflammatory responses towards IL-1α and tumor necrosis factor α in neonatal rat astrocytes. Blocking respiratory complex I and III or adenosine triphosphate (ATP) synthase did not affect activation of inflammatory signaling by IL-1α, but did elicit differential effects on inflammatory gene mRNA expression. Remarkably, mRNA and protein expression of Ptgs2 by IL-1α was consistently up-regulated when oxidative phosphorylation was inhibited. The increase of Ptgs2 resulted from mRNA stabilization. Mitochondrial inhibitors also increased IL-1α-triggered secretion of eicosanoids, such as prostaglandin E2, prostaglandin F2α, and 6-keto-prostaglandin F1α, as assessed by liquid chromatography/mass spectrometry. Mechanistically, attenuating oxidative phosphorylation elevated adenosine monophosphate (AMP) and activated AMP-activated protein kinase (AMPK). AMPK silencing prevented Ptgs2 up-regulation by mitochondrial inhibitors, while AMPK activators recapitulated Ptgs2 mRNA stability regulation. Our data indicate modulation of astrocyte inflammatory responses by oxidative metabolism, with relevance towards eicosanoid production.
Background: Receiving a cancer diagnosis can be a major life event which causes distress even years after primary treatment.
Aim: To examine the prevalence of distress in older patients with cancer (OPCs) up until 5 years post-diagnosis, and identify predictors present at time of diagnosis. Results are compared with reference groups of middle-aged patients with cancer (MPCs) and older patients without a cancer diagnosis (OPs).
Design & setting: OPCs, MPCs, and OPs participated in a longitudinal cohort study in Belgium and the Netherlands by filling in questionnaires at designated time points from 2010–2019.
Method: Data from 541 patients were analysed using multivariable logistic regression analyses.
Results: At baseline, 40% of OPCs, 37% of MPCs, and 17% of OPs reported distress. After 5 years, 35% of OPCs, 23% of MPCs, and 25% of OPs reported distress. No significant predictors for long-term distress in OPCs and OPs were found. For MPCs, it was found that baseline distress (odds ratio [OR] 2.94; 95% confidence intervals [CI] = 1.40 to 6.19) and baseline fatigue (OR 4.71; 95% CI = 1.81 to 12.31) predicted long-term distress.
Conclusion: Distress is an important problem for people with cancer, with peaks at different moments after diagnosis. Feelings of distress are present shortly after diagnosis but they decrease quickly for the majority of patients. In the long term, however, OPCs in particular appear to be most at risk for distress. This warrants extra attention from primary healthcare professionals, such as GPs who are often patients’ first medical contact point. More research into risk factors occurring later in an illness trajectory might shed more light on predictors for development of long-term distress.
Wie man weiß, zählt der Sozialstaat der Industrieepoche zu den ganz großen Innovationen in der Institutionengeschichte. Es entsteht ausgehend vom europäischen Norden und Westen und schnell mit kontinentalen und globalen Dimensionen ein hochkomplexes Geflecht aus Organisationen, aus juridischen und nicht-juridischen Normen und aus sozialen Praktiken, das auf die große – für das Schicksal der kapitalistischen Ordnung mitentscheidende – Herausforderung der "sozialen Frage" antwortet. Dabei ist dieses Gefüge nicht strukturell einheitlich, sondern durch erhebliche nationale Variation geprägt. Darüber hinaus entstehen die Institutionen im Rahmen der Einzelstaaten in keiner Weise gleichzeitig, sondern auf einer langgestreckten Zeitachse. Dieser Befund der hochgradigen Varianz kennzeichnet den Sektor der industriellen Beziehungen, in dem kollektive Akteure wesentliche Aufgaben des Sozialstaats "übernehmen", in einer besonders intensiven Weise. Es ist dieser Bereich, auf den wir sogleich näher eingehen. Im Weiteren kommt es auf dem Kontinent mit dem Aufstieg nicht-demokratischer Regime und deren Versionen des Sozialstaats zu einer zusätzlichen Komplizierung. Und schließlich tritt die neue Makrostruktur – ihren genetischen Raum überschreitend – alsbald im globalen Rahmen in Erscheinung. Ihre weltweiten Wirkungen sind immens, wie das 100-jährige Jubiläum der ILO unterstreichen mag. Und die Rückwirkungen und Irritationen vor allem aus neuen dynamischen Zentren des demokratisch verfassten Kapitalismus, zunächst der USA und dann auch Japans, sind es nicht minder. ...
Introduction: An overview of the requirements for the head of a surgical department in Germany should be given.
Materials and methods: A retrospective literature research on surgical professional policy publications of the last 10 years in Germany was conducted.
Results: Surveys show that commercial influences on medical decisions in German hospitals have today become an everyday, predominantly negative, actuality. Nevertheless, in one survey, 82.9% of surgical chief physicians reported being very satisfied with their profession, compared with 61.5% of senior physicians and only 43.4% of hospital specialists. Here, the chief physician is challenged. Only 70% of those surveyed stated that they could rely on their direct superiors when difficulties arose at work, and only 34.1% regarded feedback on the quality of their work as sufficient. The high distress rate in surgery (58.2% for all respondents) has led to a lack in desirability and is reflected in a shortage of qualified applicants for resident positions. In various position papers, surgical residents (only 35% describe their working conditions as good) demand improved working conditions. Chief physicians are being asked to facilitate a suitable work-life balance with regular working hours and a corporate culture with participative management and collegial cooperation. Appreciation of employee performance must also be expressed. An essential factor contributing to dissatisfaction is that residents fill a large part of their daily working hours with non-physician tasks. In surveys, 70% of respondents stated that they spend up to ≥3 h a day on documentation and secretarial work.
Discussion: The chief physician is expected to relieve his medical staff by employing non-physician assistants to take care of non-physician tasks. Transparent and clearly structured training to achieve specialist status is essential. It has been shown that a balanced work-life balance can be achieved for surgeons. Family and career can be reconciled in appropriately organized departments by making use of part-time and shift models that exclude 24-h shifts and making working hours more flexible.
The artworks of the Peruvian artist Carlos Runcie Tanaka, who has his British and Japanese Roots combined in his surname, refer to pre-Columbian ceramics and traditional Peruvian, Japanese and European practices. He represented Peru in ARCOmadrid 2019, the 12th Havana Biennial, the XXVI Sao Paulo Biennial, the 49th Venice Biennale, and the I Bienal Iberoamericana de Lima. In August, we sat down to talk about music, the past, the present, and the future. We discussed how all references of time can be combined into one material.
By studying pre-Columbian ceramics, researchers have developed several interpretations about the lifestyle and cosmovision of the ancient Peruvian people. Many of the techniques and motifs included in these traditional practices are still being passed on to communities throughout the country today. This ancestral knowledge is a fundamental element of identity. Therefore, ceramic is a material that has made the generation of historical discourse and the preservation of cultural memory possible. At the same time, ceramics are connected to aspects of our daily life. As objects of daily use (such as mugs, plates and bowls) they contribute to the fulfillment of basic needs. They are also included in ritual and funerary practices. In conclusion, the use of ceramics can be understood not only in a practical sense, but in an artistic sense as well.
Therapy of acute myeloid leukemia (AML) is unsatisfactory. Histone deacetylase inhibitors (HDACi) are active against leukemic cells in vitro and in vivo. Clinical data suggest further testing of such epigenetic drugs and to identify mechanisms and markers for their efficacy. Primary and permanent AML cells were screened for viability, replication stress/DNA damage, and regrowth capacities after single exposures to the clinically used pan-HDACi panobinostat (LBH589), the class I HDACi entinostat/romidepsin (MS-275/FK228), the HDAC3 inhibitor RGFP966, the HDAC6 inhibitor marbostat-100, the non-steroidal anti-inflammatory drug (NSAID) indomethacin, and the replication stress inducer hydroxyurea (HU). Immunoblotting was used to test if HDACi modulate the leukemia-associated transcription factors β-catenin, Wilms tumor (WT1), and myelocytomatosis oncogene (MYC). RNAi was used to delineate how these factors interact. We show that LBH589, MS-275, FK228, RGFP966, and HU induce apoptosis, replication stress/DNA damage, and apoptotic fragmentation of β-catenin. Indomethacin destabilizes β-catenin and potentiates anti-proliferative effects of HDACi. HDACi attenuate WT1 and MYC caspase-dependently and -independently. Genetic experiments reveal a cross-regulation between MYC and WT1 and a regulation of β-catenin by WT1. In conclusion, reduced levels of β-catenin, MYC, and WT1 are molecular markers for the efficacy of HDACi. HDAC3 inhibition induces apoptosis and disrupts tumor-associated protein expression.
Web spiders connect silk proteins, so-called spidroins, into fibers of extraordinary toughness. The spidroin N-terminal domain (NTD) plays a pivotal role in this process: it polymerizes spidroins through a complex mechanism of dimerization. Here we analyze sequences of spidroin NTDs and find an unusually high content of the amino acid methionine. We simultaneously mutate all methionines present in the hydrophobic core of a spidroin NTD from a nursery web spider’s dragline silk to leucine. The mutated NTD is strongly stabilized and folds at the theoretical speed limit. The structure of the mutant is preserved, yet its ability to dimerize is substantially impaired. We find that side chains of core methionines serve to mobilize the fold, which can thereby access various conformations and adapt the association interface for tight binding. Methionine in a hydrophobic core equips a protein with the capacity to dynamically change shape and thus to optimize its function.
Purpose: The aim of this study is to record material- and surface-dependent heat dissipation during the process of inserting implants into native animal bone. Materials and Methods: Implants made of titanium and zirconium that were identical in macrodesign were inserted under controlled conditions into a bovine rib tempered to 37 °C. The resulting surface temperature was measured on two bone windows by an infrared camera. The results of the six experimental groups, ceramic machined (1), sandblasted (2), and sandblasted and acid-etched surfaces (3) versus titanium implants with the corresponding surfaces (4, 5, and 6) were statistically tested. Results: The average temperature increase, 3 mm subcrestally at ceramic implants, differed with high statistical significance (p = 7.163 × 10−9, resulting from group-adjusted linear mixed-effects model) from titanium. The surface texture of ceramic implants shows a statistical difference between group 3 (15.44 ± 3.63 °C) and group 1 (19.94 ± 3.28 °C) or group 2 (19.39 ± 5.73 °C) surfaces. Within the titanium implants, the temperature changes were similar for all surfaces. Conclusion: Within the limits of an in vitro study, the high temperature rises at ceramic versus titanium implants should be limited by a very slow insertion velocity.
The group of neurodegenerative diseases, Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) all exhibit inclusions containing amyloid-type α-synuclein (α-syn) aggregates within degenerating brain cells. α-syn also exists as soluble oligomeric species that are hypothesized to represent intermediates between its native and aggregated states. These oligomers are present in brain extracts from patients suffering from synucleinopathies and hold great potential as biomarkers. Although easily prepared in vitro, oligomers are metastable and dissociate over time, thereby complicating α-syn oligomer research. Using the small amine-reactive cross-linker, formaldehyde (FA), we successfully stabilized α-syn oligomers without affecting their size, overall structure or antigenicity towards aggregate-conformation specific α-syn antibodies FILA and MJFR-14-6-4-2. Further, cross-linked α-syn oligomers show resistance towards denaturant like urea and SDS treatment and remain fully functional as internal standard in an aggregation-specific enzyme-linked immunosorbent assay (ELISA) despite prior incubation with urea. We propose that FA cross-linked α-syn oligomers could serve as important calibrators to facilitate comparative and standardized α-syn biomarker studies going forward.
Narratives 2.0 : a multi-dimensional approach to semi-public storytelling in WhatsApp voice messages
(2019)
Based on a corpus of voice message narratives in German WhatsApp group chats, the present study contributes to research on social media storytelling in that it focusses on stories of personal experience which are embedded in a communication platform which favours a continuous dialogic exchange, narrated to well-defined non-anonymous publics and multimodal (comprised of visual and audible posting types). To capture the characteristics of this type of social media storytelling, the paper argues that Ochs and Capps’ (2001) dimensional model originally developed for conversational narratives (including the dimensions of tellability, tellership, embeddedness, linearity, moral stance) should be expanded by the dimensions of publicness, multimodality and sequencing. The prototype of storytelling in WhatsApp group chats is based on recent personal experiences; it is related by a single teller as an initial, sequentially non-embedded and linearly organised “big package” story (in a single voice message sometimes introduced by a text message containing an abstract); other group members routinely document their evaluative stances in rather conventionalised text message responses in the semi-public group space.
This contribution aims to describe privacy, publicness and anonymity as essential analytic dimensions for media linguistic research. The dimensions are not inherent in and predetermined by the technical features and forms of communication provided by mobile devices, but are used by the participants as an orientation grid for shaping their online and offline practices in and with mobile media. Considering both mobile device use in the public realm and the dissemination of increasingly private content in social media (which is said to lead to ‘blurred boundaries’ between the private and the public), the paper provides a brief overview of the main developments in mobile media research: Studies adopting various approaches – e. g. sociological-ethnographic, linguistic and media studies – illustrate how publicness, privacy and anonymity are actively shaped and brought about by mobile media users in face-to-face and remote social encounters. As this shows that publicness, privacy and anonymity are still relevant concepts for users, future media linguistics studies should focus on the dynamic multimodal practices by which they are contextualized and accomplished.
Die peripartale Depression tritt während der Schwangerschaft und in den 12 Monaten nach der Geburt auf. Zusätzlich zu Symptomen einer depressiven Episode ist die peripartale Depression durch schwangerschafts- oder kindbezogene Symptome wie infantizidale Vorstellungen, Gefühlslosigkeit gegenüber dem Kind, Versagensängste oder Insuffizienzgefühle als Mutter gekennzeichnet. Die Prävalenz liegt bei 7 bis 10 % präpartal und 7 bis 20 % postpartal. Folge ist ein erhöhtes Risiko für frühzeitige Wehentätigkeit, geringes Geburtsgewicht, intrauterine Wachstumsstörungen, Verhaltensstörungen und gestörte kognitive Entwicklung des Kindes. Außerdem steigt die Wahrscheinlichkeit für Mutter und Kind, im weiteren Leben erneut an einer Depression zu erkranken. Therapieoptionen stehen insbesondere psychotherapeutische Verfahren wie Interpersonelle Psychotherapie und Kognitive Verhaltenstherapie und eine antidepressive Therapie zur Verfügung.
Ziel der Arbeit war es, die Publikationen zu Depression und Schwangerschaft nach szientometrischen Kriterien zu analysieren und Charakteristika und Tendenzen der Forschung zu erkennen und zu interpretieren.
Nach Definition des Suchbegriffes wurden mithilfe der Datenbank Web of Science bzw. Web of Science Core Collection alle Publikationen zu Depression im Rahmen der Schwangerschaft von 1900 bis 2012 inklusive aller bibliometrischer Daten analysiert. Die Daten wurden nach Bereinigung hinsichtlich qualitativer Gesichtspunkte und szientometrischer Parameter wie Zitierungen, Zitationsrate und modifiziertem h-Index der Publikationen, Autoren, Institutionen und Nationen untersucht. Dabei wurden zusätzlich Genderaspekte und sozioökonomische Faktoren berücksichtigt.
Insgesamt wurden 7.330 Veröffentlichungen zu Pregnancy and Depression analysiert. 95,9 % davon waren in englischer Sprache veröffentlicht. Seit 1982 konnte eine kontinuierliche Zunahme der jährlichen Publikationen verzeichnet werden. Die Zahl der Zitierungen stieg seit 1979 ebenso jährlich an. Dabei sank die Zitationsrate seit 1990. Besonders viele Arbeiten wurden im Journal of Affective Disorders und im Archives of Womens Mental Health veröffentlicht. Unter den Forschungseinrichtungen fielen die Harvard University und St. George’s, University of London durch besonders viele Publikationen auf.
Wichtigste Wissenschaftsstandorte waren die USA, Großbritannien, Australien und Kanada, was sich in den meisten Publikationen, Zitierungen und den höchsten modifizierten h Indizes äußerte, gefolgt von meist europäischen Staaten. Unter Berücksichtigung sozioökonomischer Faktoren ergaben sich mehrere Besonderheiten: Die skandinavischen Staaten Norwegen, Schweden und Finnland finden sich unter den produktivsten Ländern nach Bereinigung um die Bevölkerungszahl. Nationen mit mittlerem und niedrigem Einkommen (Low- and middle income countries = LAMICs) wie Pakistan, Südafrika und Äthiopien leisten einen relevanten Beitrag zur Forschung, berücksichtigt man das Bruttoinlandsprodukt oder die Zahl der Wissenschaftler. Internationale Kooperation dieser Nationen entstanden insbesondere mit Großbritan-nien. Durch diese Zusammenarbeit wurde einerseits auf die höhere Prävalenz von Perinataler Depression in Entwicklungs und Schwellenländern hingewiesen. Andererseits wurde die schwangerschaftsassoziierte Depression als wichtiges Element von Global Mental Health anerkannt.
Seit 1992 veröffentlichen pro Jahr mehr Frauen als Männer zu Peripartaler Depression. Die weibliche Autorenschaft liegt bei 63 %. Unter den produktivsten Wissenschaftlern sind 8 Autorinnen und 6 Autoren. Die produktivsten Autoren sind die US Amerikanerin K.L. Wisner und die Britin L. Murray. Letztere wurde am häufigsten zitiert und führt die Liste der modifizierten h Indizes mit einem Wert von 68 an. Für den britischen Autor und Begründer des Screening-Instruments Edinburgh Postnatal Depression Scale (EPDS) J.L. Cox wurde die höchste Zitationsrate berechnet.
Im Gegensatz zu Veröffentlichungen in gynäkologischen Fachzeitschriften oder szientometrischen Arbeiten zu psychiatrischen Erkrankungen wie Schizophrenie ist der Frauenanteil in allen untersuchten Teilbereichen dem Männeranteil überlegen. Einzige Ausnahme ist die Letztautorenschaft. Diese Ergebnisse stellen eine Besonderheit dar, da eine weibliche Dominanz der Wissenschaft im Schnittbereich zwischen Psychiatrie, Psychosomatik, Psychologie und Frauenheilkunde bisher nicht beschrieben ist.
Comprehensive landscape of active deubiquitinating enzymes profiled by advanced chemoproteomics
(2019)
Enzymes that bind and process ubiquitin, a small 76-amino-acid protein, have been recognized as pharmacological targets in oncology, immunological disorders, and neurodegeneration. Mass spectrometry technology has now reached the capacity to cover the proteome with enough depth to interrogate entire biochemical pathways including those that contain DUBs and E3 ligase substrates. We have recently characterized the breast cancer cell (MCF7) deep proteome by detecting and quantifying ~10,000 proteins, and within this data set, we can detect endogenous expression of 65 deubiquitylating enzymes (DUBs), whereas matching transcriptomics detected 78 DUB mRNAs. Since enzyme activity provides another meaningful layer of information in addition to the expression levels, we have combined advanced mass spectrometry technology, pre-fractionation, and more potent/selective ubiquitin active-site probes with propargylic-based electrophiles to profile 74 DUBs including distinguishable isoforms for 5 DUBs in MCF7 crude extract material. Competition experiments with cysteine alkylating agents and pan-DUB inhibitors combined with probe labeling revealed the proportion of active cellular DUBs directly engaged with probes by label-free quantitative (LFQ) mass spectrometry. This demonstrated that USP13, 39, and 40 are non-reactive to probe, indicating restricted enzymatic activity under these cellular conditions. Our extended chemoproteomics workflow increases depth of covering the active DUBome, including isoform-specific resolution, and provides the framework for more comprehensive cell-based small-molecule DUB selectivity profiling.
Age Related Macular Degeneration (AMD) is the first cause of social blindness in people aged over 65 leading to atrophy of retinal pigment epithelial cells (RPE), photoreceptors and choroids, eventually associated with choroidal neovascularization. Accumulation of undigested cellular debris within RPE cells or under the RPE (Drusen), oxidative stress and inflammatory mediators contribute to the RPE cell death. The major risk to develop AMD is the Y402H polymorphism of complement factor H (CFH). CFH interacting with oxidized phospholipids on the RPE membrane modulates the functions of these cells, but the exact role of CFH in RPE cell death and survival remain poorly understood. The aim of this study was to analyze the potential protective mechanism of CFH on RPE cells submitted to oxidative stress. Upon exposure to oxidized lipids 4-HNE (4-hydroxy-2-nonenal) derived from photoreceptors, both the human RPE cell line ARPE-19 and RPE cells derived from human induced pluripotent stem cells were protected from death only in the presence of the full length human recombinant CFH in the culture medium. This protective effect was independent from the membrane attack complex (MAC) formation. CFH maintained RPE cells tight junctions’ structure and regulated the caspase dependent apoptosis process. These results demonstrated the CFH anti-oxidative stress functions independently of its capacity to inhibit MAC formation.
Critique, and especially radical critique of reason, is under pressure from two opponents. Whereas the proponents of "post-critical" or "acritical" thinking denounce critique as an empty and self-righteous repetition of debunking, the decriers of "post-truth" accuse critique of having helped to bring about our current "post-truth" politics. Both advocate realism as a limit critique must respect, but Vogelmann defends the claim that we urgently need radical critiques of reason because they offer a more precise diagnosis of the untruths in politics the two opponents of critique are rightfully worried about. Radical critiques of reason are possible, he argues, if we turn our attention to the practices of criticizing, if we refrain from a sovereign epistemology, and if we pluralize reason without trivializing it. In order to demonstrate the diagnostic advantage of radical critiques of reason, he briefly analyzes the political and epistemic strategy at work in two exemplary untruths in politics.