40 research outputs found

    Identification of novel sirtuin inhibitors and activators

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    Sirtuins (SirT1-7) are the human homologues of the NAD+-dependent histone deacetylase Sir2 from Saccharomyces cerevisiae (ySir2). Since the overexpression of Sir2 in yeast increases lifespan, the study of mammalian sirtuins has gained widespread interest. Each sirtuin is characterized by a conserved 275 amino-acid catalytic core domain as well as by unique additional N-terminal and/or C-terminal sequences of variable length. Sirtuins hold promise as potential drug targets for the treatment of a variety of conditions, including cancer, metabolic diseases, diabetes and aging. Although, a number of sirtuin inhibitors as well as activators are known, the inhibitory mechanism of sirtuins is still unknown. In this study, we sought to identify novel inhibitors of SirT1, and we assessed their in vivo potential as chemotherapeutic agents. For this purpose, we established a fluorescence-based deacetylation assay using methyl-aminocoumarin-acetyllysine (MAL) as a substrate that is suitable for high-throughput screening. Two compound libraries (500 and 18.000 compounds, respectively) were screened for SirT1-modulating activities, and we identified 14 potential inhibitors and 12 potential activators of SirT1. Of the inhibitors, 9 showed inhibition of SirT1-dependent deacetylation of an acetylated p53 peptide. Interestingly, two of them also inhibited SirT2. Both SirT2 inhibitors were also able to inhibit the p53 deacetylation with IC50 values comparable to those determined in the MAL deacetylation assay. Moreover, we observed that the first 220 amino acids of the N-terminal region of SirT1 had an influence on the inhibitory effect of one inhibitor identified here. The potential activators failed to enhance the activity of SirT1 to deacetylate the p53 peptide. Surprisingly, one of them showed strong inhibition of SirT1 in this assay (Hill 2012) as well as inhibition of MAL deacetylation by ySir2 and SirT2. Subsequently, we determined the anticancer potential of the inhibitors identified in this study by different in vivo experiments with the lung cancer cell lines A549 and H1299. Three compounds that inhibited cell viability and proliferation of these cancer cells in a dose-dependent manner were pursued in more detail. These three inhibitors induced an additional increase of apoptosis after combined treatment with the chemotherapeutic agent etoposide. We observed that the additional increase of apoptosis mediated by one of theses inhibitors was p53-dependent. In summary, this study has led us to identify one SirT1 inhibitor as well as two SirT2 inhibitors that showed antiproliferation potential and can be developed further for cancer therapy.Sirtuine (SirT1-SirT7) sind die human Homologe der NAD+-abhĂ€ngigen Histondeacetylase Sir2 aus der BĂ€ckerhefe Saccharomyces cerevisiae. Seit der Beobachtung, dass die Überexprimierung von Sir2 in Hefen einen lebensverlĂ€ngernden Einfluss hat, ist das Interesse an der Erforschung der Sirtuine enorm gewachsen. Jedes Sirtuin besitzt eine konservierte katalytische DomĂ€ne von etwa 275 AminosĂ€uren, sowie N-terminale und/oder C-terminale Sequenzen, die sich in ihrer LĂ€nge unterscheiden. Sirtuine sind vielversprechende Ansatzpunkte fĂŒr die Behandlung zahlreicher Krankheiten, wie zum Beispiel Krebs, Stoffwechselkrankheiten, Diabetes und Alterung. Obwohl bereits einige Sirtuin-Inhibitoren und -Aktivatoren bekannt sind, ist der Mechanismus der Inhibition ungeklĂ€rt. Das Ziel der vorliegenden Arbeit war es, neue Sirtuin-Inhibitoren zu identifizieren und deren in vivo Potential als Chemotherapeutika zu untersuchen. Dazu wurde ein fluoreszenz-basierter Assay etabliert, bei dem ein Methyl-Aminocoumarin-Acetyllysine (MAL) als Substrat verwendet wurde, der fĂŒr High-throughput Screening geeignet ist. FĂŒr die Identifizierung von SirT1-Modulatoren wurden zwei Bibliotheken (500 und 18.000 Substanzen) gescreent, wobei 14 potentielle Inhibitoren, sowie 12 potentielle Aktivatoren identifiziert wurden. Von diesen Inhibitoren zeigten 9 auch Inhibition von SirT1-abhĂ€ngiger Deacetylierung eines acetylierten p53-Peptids. Des weiteren konnten zwei dieser Substanzen auch SirT2 inhibieren. Beide SirT2 Inhibitoren waren auch in der Lage, die p53 Deacetylierung zu inhibieren. Weiterhin haben wir beobachtet, dass die ersten 220 AminosĂ€uren der N-terminalen Region von SirT1 einen Einfluss auf die Wirkung eines Inhibitors, der in dieser Arbeit identifiziert wurde, haben. Die potentiellen Aktivatoren zeigten keine Steigerung der SirT1 AktivitĂ€t bei der Deacetylierung des p53-Peptids. Erstaunlicherweise zeigte einer von ihnen starke Inhibition von SirT1 im p53 Deacetylierungs Assay (Hill 2012), sowie des ySir2 aus S. cerevisiae und von SirT2 mit MAL als Substrat. Im weiteren wurde das Potential der identifizierten Inhibitoren als Zytostatika mit unterschiedlichen in vivo Experimenten unter Verwendung der Lungenkrebszelllinien A549 und H1299 untersucht. Drei von ihnen, die der Lage waren, die ZellvitalitĂ€t sowie die Zellteilung dosisabhĂ€ngigen zu inhibieren wurden weiter untersucht. Interessanterweise verursachten sie einen zusĂ€tzlichen Anstieg der Apoptose nach kombinierter Behandlung mit dem Chemotherapeutikum Etoposide. Wir konnten zeigen, dass dieser Inhibitor-induzierte zusĂ€tzliche Anstieg der Apoptose zum Teil p53 abhĂ€ngig war. Somit haben wir insgesamt einen SirT1-Inhibitor und zwei SirT2-Inhibitoren identifiziert, die ein Antiproliferationspotential aufweisen und fĂŒr Krebstherapien weiterentwickelt werden können

    Use of Physiotherapy Prior to Total Knee Arthroplasty-Results of the Prospective FInGK Study

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    Background: Data regarding physiotherapy (PT) utilization prior to total knee arthroplasty (TKA) are insufficient. Therefore, this study aims to examine which percentage of patients receive PT within 12 months prior to TKA and which factors are associated with its use. Methods: Consecutive patients (≄18 years) undergoing primary or revision TKA in a German university hospital were recruited. A questionnaire including information on PT utilization, demography, and socioeconomics was collected one day prior to surgery and linked to medical hospital records. Multivariable logistic regression was conducted to determine variables associated with the use of PT. Results: A total of 241 out of 283 (85%) patients participated (60% female; mean age: 68.4 years). Overall, 41% received PT at least once during 12 months prior to TKA, women more frequently than men (48% vs. 29%). Although high disease burden was associated with increased utilization, about one in two in this condition did not receive PT. Multivariable logistic regression showed that age 75+ years, low education level, and moderate-to-severe depressive symptoms were associated with decreased PT utilization. Conclusions: We found low use of recommended PT management in patients prior to TKA. This potential underuse was even higher in some vulnerable subgroups, indicating inequalities. Prescribers as well as patients should integrate PT more consistently into osteoarthritis management

    Disease burden of and expectations from surgery in patients prior to total knee arthroplasty:Results of the prospective FInGK study

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    Background: Disease burden in patients prior to total knee arthroplasty (TKA) varies widely between studies and countries. We aimed to characterize individuals undergoing TKA and examine their expectations from the surgery, focusing on variations in disease burden. Methods: Consecutive patients undergoing primary TKA in a German university hospital were recruited. A questionnaire including information on disease burden, preoperative expectations from surgery, health care utilization, demography, and socioeconomics was collected one day prior to surgery and linked to data from medical records. Patients were categorized into disease burden quartiles using the Western Ontario and McMaster Universities Osteoarthritis Index’ (WOMAC) total score. Subsequently, study population's characteristics and expectations from surgery were analyzed stratified by disease burden. Results: A total of 196 patients were included (41 % male; mean age: 68.2 years). The median WOMAC was 52.0 (IQR: 41.0–58.0). Patients in Q1 were more often males (Q1: 63 % vs Q4: 29 %) and had a shorter duration of complaints with the impaired knee. They were also less restricted in social participation, reported less often signs of depression, and were less often treated with physiotherapy (Q1: 27 % vs Q4: 54 %). Furthermore, expectations from surgery were highest in patients with a low disease burden. Conclusion: We found large variations in disease burden with a considerable number of patients undergoing TKA whose functional capacity is still maintained and for which guideline-recommended conservative treatment options are not fully exhausted. Further research on this subgroup as well as establishing an international consensus on specific thresholds for TKA indication are needed.</p

    Disease burden of and expectations from surgery in patients prior to total knee arthroplasty:Results of the prospective FInGK study

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    Background: Disease burden in patients prior to total knee arthroplasty (TKA) varies widely between studies and countries. We aimed to characterize individuals undergoing TKA and examine their expectations from the surgery, focusing on variations in disease burden. Methods: Consecutive patients undergoing primary TKA in a German university hospital were recruited. A questionnaire including information on disease burden, preoperative expectations from surgery, health care utilization, demography, and socioeconomics was collected one day prior to surgery and linked to data from medical records. Patients were categorized into disease burden quartiles using the Western Ontario and McMaster Universities Osteoarthritis Index’ (WOMAC) total score. Subsequently, study population's characteristics and expectations from surgery were analyzed stratified by disease burden. Results: A total of 196 patients were included (41 % male; mean age: 68.2 years). The median WOMAC was 52.0 (IQR: 41.0–58.0). Patients in Q1 were more often males (Q1: 63 % vs Q4: 29 %) and had a shorter duration of complaints with the impaired knee. They were also less restricted in social participation, reported less often signs of depression, and were less often treated with physiotherapy (Q1: 27 % vs Q4: 54 %). Furthermore, expectations from surgery were highest in patients with a low disease burden. Conclusion: We found large variations in disease burden with a considerable number of patients undergoing TKA whose functional capacity is still maintained and for which guideline-recommended conservative treatment options are not fully exhausted. Further research on this subgroup as well as establishing an international consensus on specific thresholds for TKA indication are needed.</p

    Disease burden of and expectations from surgery in patients prior to total knee arthroplasty:Results of the prospective FInGK study

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    Background: Disease burden in patients prior to total knee arthroplasty (TKA) varies widely between studies and countries. We aimed to characterize individuals undergoing TKA and examine their expectations from the surgery, focusing on variations in disease burden. Methods: Consecutive patients undergoing primary TKA in a German university hospital were recruited. A questionnaire including information on disease burden, preoperative expectations from surgery, health care utilization, demography, and socioeconomics was collected one day prior to surgery and linked to data from medical records. Patients were categorized into disease burden quartiles using the Western Ontario and McMaster Universities Osteoarthritis Index’ (WOMAC) total score. Subsequently, study population's characteristics and expectations from surgery were analyzed stratified by disease burden. Results: A total of 196 patients were included (41 % male; mean age: 68.2 years). The median WOMAC was 52.0 (IQR: 41.0–58.0). Patients in Q1 were more often males (Q1: 63 % vs Q4: 29 %) and had a shorter duration of complaints with the impaired knee. They were also less restricted in social participation, reported less often signs of depression, and were less often treated with physiotherapy (Q1: 27 % vs Q4: 54 %). Furthermore, expectations from surgery were highest in patients with a low disease burden. Conclusion: We found large variations in disease burden with a considerable number of patients undergoing TKA whose functional capacity is still maintained and for which guideline-recommended conservative treatment options are not fully exhausted. Further research on this subgroup as well as establishing an international consensus on specific thresholds for TKA indication are needed.</p

    Disease burden of and expectations from surgery in patients prior to total knee arthroplasty:Results of the prospective FInGK study

    Get PDF
    Background: Disease burden in patients prior to total knee arthroplasty (TKA) varies widely between studies and countries. We aimed to characterize individuals undergoing TKA and examine their expectations from the surgery, focusing on variations in disease burden. Methods: Consecutive patients undergoing primary TKA in a German university hospital were recruited. A questionnaire including information on disease burden, preoperative expectations from surgery, health care utilization, demography, and socioeconomics was collected one day prior to surgery and linked to data from medical records. Patients were categorized into disease burden quartiles using the Western Ontario and McMaster Universities Osteoarthritis Index’ (WOMAC) total score. Subsequently, study population's characteristics and expectations from surgery were analyzed stratified by disease burden. Results: A total of 196 patients were included (41 % male; mean age: 68.2 years). The median WOMAC was 52.0 (IQR: 41.0–58.0). Patients in Q1 were more often males (Q1: 63 % vs Q4: 29 %) and had a shorter duration of complaints with the impaired knee. They were also less restricted in social participation, reported less often signs of depression, and were less often treated with physiotherapy (Q1: 27 % vs Q4: 54 %). Furthermore, expectations from surgery were highest in patients with a low disease burden. Conclusion: We found large variations in disease burden with a considerable number of patients undergoing TKA whose functional capacity is still maintained and for which guideline-recommended conservative treatment options are not fully exhausted. Further research on this subgroup as well as establishing an international consensus on specific thresholds for TKA indication are needed.</p

    Dresdner Lebenslagen 60+: Bericht zur Lebenssituation von Dresdnerinnen und Dresdnern ab 60 Jahren (LAB60+ Studie): Ein Kooperationsprojekt zwischen der Landeshauptstadt Dresden und der Technischen UniversitÀt Dresden

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    Die Stadtverwaltung hat es sich zur Aufgabe gemacht, auf die BedĂŒrfnisse und Bedarfe unserer Seniorinnen und Senioren noch besser einzugehen. Deswegen wurde diese Studie in Auftrag gegeben. Sie stellt eine hervorragende wissenschaftliche ÜberprĂŒfung und ErgĂ€nzung unseres bisherigen praktischen Tuns rund um das Thema Altern in Dresden dar und setzt sich unter anderem mit Elementen des bereits bestehenden Fachplans Seniorenarbeit und Altenhilfe inklusive des Aktionsplans fĂŒr gesundes und aktives Altern, dem Dresdner Kompetenzzentrum fĂŒr den Übergang in den Ruhestand und dem Pflegenetzwerk auseinander. Weg vom defizitorientierten, hin zum ressourcenorientierten Ansatz lautet ein Prinzip der Dresdner Seniorenpolitik. Es liegt auch der LAB60+ Studie zugrunde. Sie wirft einen umfassenden Blick auf die Potenziale und Chancen in der vielgliedrigen nachberuflichen Lebensphase. Beleuchtet werden notwendige Rahmenbedingungen fĂŒr eine hohe Lebenszufriedenheit, fĂŒr Selbsthilfe und fĂŒr möglichst eigenstĂ€ndiges Wohnen je nach Lebensentwurf. Knapp 2.400 ĂŒber 60-JĂ€hrige nahmen an der Befragung teil und haben sich dem Fragebogen mit ĂŒber 90 Fragen gestellt. Die hohe RĂŒcklaufquote von 40 Prozent verdeutlicht das hohe Interesse der Zielgruppe und die Wichtigkeit des Themas. Die Kooperation mit der Technischen UniversitĂ€t Dresden habe ich als Ă€ußerst nĂŒtzlich und gewinnbringend fĂŒr beide Seiten erlebt. Die Ergebnisse und Ableitungen der LAB60+ Studie liefern einen konstruktiven Beitrag fĂŒr die fachliche und kommunalpolitische Auseinandersetzung in unserer Stadt. Bei der Entwicklung konkreter Maßnahmen ist mir eine Beteiligung der Dresdnerinnen und Dresdner sehr wichtig. DafĂŒr ist eine Seniorinnen- und Seniorenkonferenz geplant. KĂŒnftig wollen wir die Lebenssituation der Ă€lteren und alten Menschen und das Miteinander der Generationen regelmĂ€ĂŸig untersuchen und damit eine wissenschaftlich basierte Grundlage fĂŒr weitere Diskussion und Entscheidung entwickeln. Redaktionsschluss: Januar 202

    Außerschulische Lernorte von Kindern : Reflexionen - Konzeptionen - Perspektiven

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    Weitere Hrsg.: Martin Gröger, Daria Johanna Schneider, Jutta Wiesemann. Publikation anlĂ€sslich der Tagung „Orte und RĂ€ume der Generationenvermittlung – Außerschulisches Lernen von Kindern“, UniversitĂ€t Siegen, 5.-6. Oktober 2017Die WertschĂ€tzung des außerschulischen Lernens hat in der SchulpĂ€dagogik eine lange Tradition und ist besonders in der Grundschule und im Sachunterricht etabliert. Mit einem Blick auf Möglichkeiten der Vernetzung schulischer und außerschulischer Lernwelten rĂŒckt das Bildungspotenzial und die Bildungswirksamkeit außerschulischer Lernorte zunehmend in den Aufmerksamkeitsfokus bildungspolitischer, schulpĂ€dagogischer sowie didaktischer Reflexion. Eine Gelegenheit zu einer vertieften Auseinandersetzung mit diversen außerschulischen Lernarrangements bot die Tagung zum Thema „Orte und RĂ€ume der Generationenvermittlung – außerschulisches Lernen von Kindern“, die im Oktober 2017 an der UniversitĂ€t Siegen stattfand. Die vielfĂ€ltigen Impulse und wertvollen Überlegungen der Tagungsteilnehmerinnen und -teilnehmer werden in der vorliegenden Publikation „Außerschulische Lernorte von Kindern – Reflexionen – Konzeptionen – Perspektiven“ aufgegriffen. Die BeitrĂ€ge des Bandes gliedern sich in drei Themenblöcke: zum einen werden konzeptionelle Überlegungen zum außerschulischen Lernort vorgestellt, zum anderen eröffnet der Band Einblicke in die Entwicklung und Ausgestaltung sowie in den Einsatz von Materialien am außerschulischen Lernort. Der dritte Themenblock gibt abschließend einige Beispiele fĂŒr die mannigfaltigen Möglichkeiten, schulische und außerschulische Lernorte effektiv zu vernetzen

    Regionale Standards: Ausgabe 2019

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    Die "Regionalen Standards" gehen zurĂŒck auf die Initiative eines gemeinsamen Arbeitskreises, bestehend aus Vertretern des Statistischen Bundesamtes, der Arbeitsgemeinschaft Sozialwissenschaftlicher Institute e.V. (ASI) und des ADM Arbeitskreis Deutscher Markt- und Sozialforschungsinstitute e.V. Sie stellen ein Angebot fĂŒr die Forschung in der Bundesrepublik Deutschland dar. Die "Regionalen Standards" beschreiben Gebietsabgrenzungen und Instrumente zur Typisierung von Regionen, wie sie in der Bundesrepublik Deutschland von der amtlichen Statistik und/oder der Markt- und Sozialforschung in gewisser RegelmĂ€ĂŸigkeit eingesetzt werden. ZusĂ€tzlich werden DatensĂ€tze aus unterschiedlichen Quellen vorgestellt, die fĂŒr die Regionalisierung von Bevölkerungsumfragen genutzt werden können und fĂŒr die Forschung (teils jedoch mit EinschrĂ€nkungen) zur VerfĂŒgung stehen
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