25 research outputs found
CSR Communication on Twitter - A Scoping Review on Social Media Mining and Analytic Methods
Adopting corporate social responsibility (CSR) is becoming increasingly mandatory as international legislation puts pressure on companies to implement and report on appropriate CSR measures. As of 2024, a significant number of companies will need to report on CSR topics for the first time. To identify relevant topics that resonate best in the industry or even with one's own stakeholder groups and should therefore be picked up, addressed and reported on preferentially, social media mining (SMM) can be an efficient ap-proach for companies. By reviewing applied SMM and analytic methods of Twitter data, we identified four methodological approaches that use algorithms to identify relevant CSR topics for companies to engage with. This scoping review thus provides a systematized overview of SMM pipelines for use, being equally relevant for academics and practitioners aiming at computational analysis of Twitter content regarding CSR activities and communication
Prodrug converting enzyme gene delivery by L. monocytogenes
<p>Abstract</p> <p>Background</p> <p><it>Listeria monocytogenes </it>is a highly versatile bacterial carrier system for introducing protein, DNA and RNA into mammalian cells. The delivery of tumor antigens with the help of this carrier into tumor-bearing animals has been successfully carried out previously and it was recently reported that <it>L. monocytogenes </it>is able to colonize and replicate within solid tumors after local or even systemic injection.</p> <p>Methods</p> <p>Here we report on the delivery of two prodrug converting enzymes, purine-deoxynucleoside phosphorylase (PNP) and a fusion protein consisting of yeast cytosine deaminase and uracil phosphoribosyl transferase (FCU1) into cancer cells in culture by <it>L. monocytogenes</it>. Transfer of the prodrug converting enzymes was achieved by bacterium mediated transfer of eukaryotic expression plasmids or by secretion of the proteins directly into the host cell cytosol by the infecting bacteria.</p> <p>Results</p> <p>The results indicate that conversion of appropriate prodrugs to toxic drugs in the cancer cells occured after both procedures although <it>L. monocytogenes</it>-mediated bactofection proved to be more efficient than enzyme secretion 4T1, B16 and COS-1 tumor cells. Exchanging the constitutively P<sub>CMV</sub>-promoter with the melanoma specific P<sub>4xTETP</sub>-promoter resulted in melanoma cell-specific expression of the prodrug converting enzymes but reduced the efficiencies.</p> <p>Conclusion</p> <p>These experiments open the way for bacterium mediated tumor specific activation of prodrugs in live animals with tumors.</p
Impact of COVID-19 Pandemic on TAVR Activity: A Worldwide Registry
Background: The COVID-19 pandemic had a considerable impact on the provision of structural heart intervention worldwide. Our objectives were: 1) to assess the impact of the COVID-19 pandemic on transcatheter aortic valve replacement (TAVR) activity globally; and 2) to determine the differences in the impact according to geographic region and the demographic, development, and economic status of diverse international health care systems.
Methods: We developed a multinational registry of global TAVR activity and invited individual TAVR sites to submit TAVR implant data before and during the COVID-19 pandemic. Specifically, the number of TAVR procedures performed monthly from January 2019 to December 2021 was collected. The adaptive measures to maintain TAVR activity by each site were recorded, as was a variety of indices relating to type of health care system and national economic indices. The primary subject of interest was the impact on TAVR activity during each of the pandemic waves (2020 and 2021) compared with the same period pre–COVID-19 (2019).
Results: Data were received from 130 centers from 61 countries, with 14 subcontinents and 5 continents participating in the study. Overall, TAVR activity increased by 16.7% (2,337 procedures) between 2018 and 2019 (ie, before the pandemic), but between 2019 and 2020 (ie, first year of the pandemic), there was no significant growth (–0.1%; –10 procedures). In contrast, activity again increased by 18.9% (3,085 procedures) between 2020 and 2021 (ie, second year of the pandemic). During the first pandemic wave, there was a reduction of 18.9% (945 procedures) in TAVR activity among participating sites, while during the second and third waves, there was an increase of 6.7% (489 procedures) and 15.9% (1,042 procedures), respectively. Further analysis and results of this study are ongoing and will be available at the time of the congress.
Conclusion: The COVID-19 pandemic initially led to a reduction in the number of patients undergoing TAVR worldwide, although health care systems subsequently adapted, and the number of TAVR recipients continued to grow in subsequent COVID-19 pandemic waves.
Categories: STRUCTURAL: Valvular Disease: Aorti
Development of a DNA delivery system using virulence-attenuated Listeria strains
Virulenz-attenuierte Bakterien sind geeignete Vektoren für den Transport von Vakzine-DNA in das Zytosol von Antigen-präsentierenden Zellen ("DNA delivery"). In dieser Arbeit wurde dazu das intrazelluläre Bakterium Listeria monocytogenes verwendet, welches sich im Zytosol von Zellen vermehrt und fortbewegt. Ausgestattet mit einer intrazellulären Lysis-Kassette kann Listeria in vitro effektiv Plasmid-DNA in das Zytosol verschiedener Zelltypen freisetzen. Zur Virulenz-Attenuierung wurde das Gen iap im Chromosom des Bakteriums deletiert. Der daraus resultierte Stamm, in Folgenden als iap bezeichnet, erwies sich als hoch attenuiert im Modell der murinen Listeriose. Diese Attenuation konnte auf einen Defekt in der Beweglichkeit der Bakterien innerhalb von Wirtszellen zurückgeführt werden, da sich bei diesem Stamm das Protein ActA, das essentiell für die Aktin-basierte Motilität von L. monocytogenes ist, fehlerhaft auf der Oberfläche der Bakterien anordnet. Zusätzlich konnte demonstriert werden, dass iap in der Zellteilung beeinträchtigt ist und deshalb eine veränderte Morphologie aufweist. Im Rahmen dieser Arbeit wurde ein so genanntes "Balanced-lethal" System etabliert. Dazu wurde das essentielle Gens trpS im Chromosom deletiert, während gleichzeitig eine trpS-Expressions-Kassette auf einem Vakzine-Plasmid inseriert wurde. Dieses System gewährleistet, dass das Trägerbakterium dieses Plasmid weder in vitro noch in vivo verliert. Dies ist besonders wichtig im Hinblick auf eine bakteriolytische Lysis-Kassette, welche ebenfalls auf diesem Plasmid kodiert ist. Es wurden verschiedene Lysis-Kassetten, die alle aus einem Listeria-spezifischen Phagenlysin und einem vorangestellten zytosolischen listeriellen Promotor zusammengesetzt waren, miteinander verglichen. Dabei wurde beobachtet, dass die für die Übertragung von Plasmid-DNA in das Zytosol von Wirtszellen wirksamste Phagenlysin-Kassette (PactA-ply118) die Bakterien in vitro nur partial abtötet, während sie in vivo zu einer besonders hohen Attenuation der Bakterien führt. Unter Verwendung dieses "DNA delivery" Systems wurden Mäuse oral mit Listerien infiziert, die ein DNA-Vakzine-Plasmid zur Expression des Leishmania Antigens KMP-11 trugen. Dabei konnte bei 27 % aller Tiere, die zweimal mit diesen Listerien infiziert worden sind, eine KMP-11 spezifische, proliferative Immunantwort gemessen werden. Listerien, die einen Defekt in ihrer Motilität besitzen (delta-iap, delta-actA), erwiesen sich darin beeinträchtigt, Plasmid-DNA im Zytosol von Zellen freizusetzen. Anhand dieser Stämme konnte gezeigt werden, dass die Fähigkeit von L. monocytogenes, sich innerhalb von Zellen zu bewegen und in benachbarte Zellen einzudringen eine wichtige Voraussetzung für einen effizienten Transfer von Plasmid-DNA in vitro darstellt.Virulence-attenuated bacteria are useful carriers to introduce a DNA vaccine into antigen presenting cells (DNA delivery). To this end, the intracellular bacterium Listeria monocytogenes was used in this work, which is able to replicate and spread inside host cells. Hence Listeriae are able to efficiently release plasmid DNA within the cytosol in vitro when they are provided with a cytosolic lysis cassette. The expression of the antigen by the cell leads to the presentation of antigenic epitopes on the cell's major histocompatibilty complex (MHC) class I molecules, due to the antigen being endogenous. This stimulates the activation of CD8+ T cells which are important for clearance of tumours, parasites and virus infected cells. In order to create a virulence-attenuated carrier strain the gene iap was deleted in the chromosome of the bacterium. The resulting strain, designated as iap, was shown to be highly attenuated in mice. This was due to a defect of the intracellular motility since ActA, a protein which is necessary for actin-based motility of Listeria, was localised incorrectly at the bacterial surface. Additionally, it was demonstrated that iap is impaired in cell division which leads to an altered cell morphology. In this work a so-called balanced-lethal plasmid system was established. The essential gene trpS was deleted from the chromosome of L. monocytogenes and a trpS transcription unit was inserted in a vaccine DNA plasmid thus ensuring that no plasmid loss happens in vitro and also within the host organism. This is in particular important in terms of a bacteriolytic lysis cassette which is also encoded by the plasmid. Different lysis cassettes were tested consisting of a Listeria-specific phage lysin and an intracellular promoter of Listeria. The cassette PactA-ply118 was found the be most effective due to its DNA delivery capacity but it mediates only a partial lysis of the intracellular bacteria. However, this cassette leads to a high attenuation of Listeria in mice. Using this DNA delivery system mice were orally infected with Listeria harbouring a KMP-11 expression plasmid. 27 % of animals infected twice exhibited a specific proliferative response to the leismanial antigen KMP-11. Listeriae with a defect in their spreading capacity (delta-iap, delta-actA) were impaired in the cytosolic release of plasmid DNA. With these strains it was demonstrated, that spreading is an important prerequisite for L. monocytogenes to be an efficient DNA delivery carrier in vitro
Corporate Social Responsibility on Twitter: A Review of Topics and Digital Communication Strategies’ Success Factors
Corporate social responsibility (CSR) has become increasingly important for companies in recent years. On the one hand, regulatory frameworks require the disclosure of measures for sustainable management. On the other hand, for long-term corporate success, stakeholders must be strategically engaged in the dialog on sustainability aspects. Social media and Twitter in particular offer the potential to foster a meaningful stakeholder dialogue on CSR topics. Twitter’s strategic realignment due to Elon Musk’s acquisition in the fall of 2022, provides an opportunity to capture research results on activities and strategies on the platform systematically, and to synthesize information for future comparative longitudinal studies of changes in usage. We conducted a literature review including 42 papers to contribute to the body of evidence on CSR communication strategies on Twitter across industries and countries, by deriving interdisciplinary suggestions for strategic CSR-related stakeholder management. Results cover relevant CSR topics, prioritized stakeholder groups for CSR communication on Twitter, and successful communication strategies for companies to obtain beneficial results, such as generating social media capital. The results contribute to the strategic planning and implementation of CSR stakeholder management on Twitter, and offer starting points for future studies on social-media mining and CSR communication strategies
Corporate Social Responsibility on Twitter: A Review of Topics and Digital Communication Strategies’ Success Factors
Corporate social responsibility (CSR) has become increasingly important for companies in recent years. On the one hand, regulatory frameworks require the disclosure of measures for sustainable management. On the other hand, for long-term corporate success, stakeholders must be strategically engaged in the dialog on sustainability aspects. Social media and Twitter in particular offer the potential to foster a meaningful stakeholder dialogue on CSR topics. Twitter’s strategic realignment due to Elon Musk’s acquisition in the fall of 2022, provides an opportunity to capture research results on activities and strategies on the platform systematically, and to synthesize information for future comparative longitudinal studies of changes in usage. We conducted a literature review including 42 papers to contribute to the body of evidence on CSR communication strategies on Twitter across industries and countries, by deriving interdisciplinary suggestions for strategic CSR-related stakeholder management. Results cover relevant CSR topics, prioritized stakeholder groups for CSR communication on Twitter, and successful communication strategies for companies to obtain beneficial results, such as generating social media capital. The results contribute to the strategic planning and implementation of CSR stakeholder management on Twitter, and offer starting points for future studies on social-media mining and CSR communication strategies
Influencer und das Problem mit dem Sixpack
<jats:title>Zusammenfassung</jats:title><jats:sec>
<jats:title>Hintergrund</jats:title>
<jats:p>Kinder und Jugendliche nutzen zum Austausch sowie zur Informationsgewinnung täglich intensiv soziale Netzwerke und lassen sich von Influencern maßgeblich beeinflussen. Dabei werden verstärkt gesundheitsrelevante Inhalte, die Ernährung und Bewegung umfassen, thematisiert.</jats:p>
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<jats:title>Ziel</jats:title>
<jats:p>Die Studie soll zu einem besseren Verständnis der Merkmale gesundheitsbezogener Bildsprache von deutschen Fitnessinfluencern auf Instagram beitragen. Ein besonderer Fokus liegt auf dem dargestellten Körperbild.</jats:p>
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<jats:title>Material und Methoden</jats:title>
<jats:p>In einem quantitativen Ansatz werden 1000 nicht-kampagnengesteuerte Beiträge zu Ernährung und Bewegung ausgewählter Fitnessinfluencer auf Instagram analysiert.</jats:p>
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<jats:title>Ergebnisse</jats:title>
<jats:p>Zentral bei der Influencerkommunikation ist die Inszenierung der eigenen Person. Das dargestellte Körperbild spielt hier eine entscheidende Rolle. Hauptsächlich zu den Themen Ernährung und Bewegung kommunizierende (und werbende) Influencer positionieren ihren gesamten Körper in figurbetonender oder hautentblößender Form.</jats:p>
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<jats:title>Schlussfolgerung</jats:title>
<jats:p>Soziale Medien sind Settings, in welchen gesundheitsrelevante Themen intensiv kommuniziert werden. Das Werben für Sportbekleidung und Nahrungsergänzungsmittel steht hier speziell auf Kanälen von deutschen Fitnessinfluencern im Fokus. Strategien zur Prävention und Förderung der Gesundheit sollten junge Menschen in dieser digitalen Lebenswelt abholen und dem durch Influencer beworbenem Körperideal entgegenwirken.</jats:p>
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Deletion of the Gene Encoding p60 in Listeria monocytogenes Leads to Abnormal Cell Division and Loss of Actin-Based Motility
Protein p60 encoded by the iap gene is regarded as an essential gene product of Listeria monocytogenes. Here we report, however, the successful construction of a viable iap deletion mutant of L. monocytogenes EGD. The mutant, which produces no p60, shows abnormal septum formation and tends to form short filaments and hooked forms during logarithmic growth. These abnormal bacterial cells break into almost normal sized single bacteria in the late-stationary-growth phase. The iap mutant is strongly attenuated in a mouse model after intravenous injection, demonstrating the importance of p60 during infection, and the invasiveness of the Δiap mutant for 3T6 fibroblasts and Caco-2 epithelial cells is slightly reduced. Upon uptake by epithelial cells and macrophages, the iap mutant escapes from the phagosome into the cytosol with the same efficiency as the wild-type strain, and the mutant bacteria also grow intracellularly at a rate similar to that of the wild-type strain. Intracellular movement and cell-to-cell spread are drastically reduced in various cell lines, since the iap-negative bacteria fail to induce the formation of actin tails. However, the bacteria are covered with actin filaments. Most intracellular bacteria show a nonpolar and uneven distribution of ActA around the cell, in contrast to that for the wild-type strain, where ActA is concentrated at the old pole. In an iap(+) revertant strain that produces wild-type levels of p60, intracellular movement, cell-to-cell spread, and polar distribution of ActA are fully restored. In vitro analysis of ActA distribution on the filaments of the Δiap strain shows that the loss of bacterial septum formation leads to ActA accumulation at the presumed division sites. In the light of data presented here and elswhere, we propose to rename iap (invasion-associated protein) cwhA (cell wall hydrolase A)