Halbjahresergebnisse einer neuen faltbaren Hinterkammerlinse aus Acryl, AcrySof® MA60BM

Das Forschungsziel dieser Arbeit war die Abklärung der Frage, ob sich in implantierten Intraokularlinsen der Marke Acrysof®, die in Deutschland kurz nach deren Markteinführung erworben wurden, Mikrovakuolen im Optikkörper befinden. Diese sogenannten Glistenings, die der Hersteller auf eine neuartige Verpackung zurückführte, welche ausschließlich in den Vereinigten Staaten Verwendung fand, führten in den USA zu Explantationen und zum Rückruf so verpackter Kunstlinsen dieses Typs. Unser Arbeitsprogramm umfaßte hauptsächlich die Untersuchung von Patienten, bei denen eine Acrysof®-Intraokularlinse implantiert wurde, an der Spaltlampe und anschließende Dokumentation mittels Fotospaltlampe. Zusätzlich wurden Sehschärfebestimmungen durchgeführt. Analog wurden Untersuchungen und Dokumentationen bei Patienten, denen im gleichen Zeitraum und vom gleichen Operateur eine herkömmliche PMMA-Kunstlinse implantiert wurde, durchgeführt. In allen untersuchten Intraokularlinsen des neuen Modells aus Acryl konnten Mikrovakuolen festgestellt und fotografisch dokumentiert werden. Diese Veränderungen konnten in keiner der PMMA-Kunstlinsen beobachtet werden. In unseren Ergebnissen fanden sich sonst durchgehend Hinweise auf die mittlerweile von anderen gewonnenen Erkenntnisse über die neue Linse. Es konnten keine Hinweise auf eine Visusminderung durch die Glistenings festgestellt werden. Die Analyse der Literatur ergab, daß nach dem heutigem Stand der Erkenntnisse über die Glistenings, von einer Flüssigkeitsaufnahme in den Optikkörper der IOL ausgegangen wird. Die Flüssigkeit sammelt sich in einige mikrometer großen Räumen in der Polymerstruktur der Kunstlinse. Diese Mikrovakuolen werden durch die Brechkraftdifferenz zwischen deren Inhalt und dem IOL-Material optisch sichtbar und erscheinen bei der Spaltlampenuntersuchung als multiple Glitzerpunkte. Experimentelle Arbeiten haben gezeigt, daß die Ausbildung der Mikrovakuolen durch Temperaturschwankungen und durch die Anwesenheit von Serum begünstigt wird. Ein verstärktes Vorkommen der Glistenings bei Patienten, bei denen sich durch Beeinträchtigung der Blut-Kammerwasser-Schranke oder der Blut-Retina-Schranke, Serumbestandteile im Kammerwasser befinden können, hier sind besonders Diabetiker zu nennen, wurde von einigen Autoren berichtet. Auch wir konnten bei einer nachträglichen Auswertung unserer Unterlagen Hinweise darauf finden, daß es bei solchen Patienten zur verstärkten Glisteningbildung kommt. Die Aussage der Herstellerfirma, die Glistenings hingen mit der neuartigen Verpackung und Sterilisation der IOLs in dem AcryPak-System, welches nur in den USA zum Einsatz kam und 1995 vom Markt genommen wurde, zusammen, wurde durch unsere Ergebnisse widerlegt. Besonders die frühere englischsprachige Literatur spiegelt einen Konsens mit der vom Hersteller vertretenen Auffassung wider. Neuere Arbeiten, die unsere Ergebnisse bestätigen weisen auf ein Poster auf einem Kongress 1999 in Seattle als erstes bekanntwerden von Glistenings in herkömmlich verpackten AcrySof®-IOL hin, obwohl schon frühere Berichte von Autoren aus Europa, auch von unserer Arbeitsgruppe, vorlagen. Die Mikrovakuolen haben nur in sehr seltenen Einzelfällen, bei denen es zu massenhaftem Vorkommen gekommen war, zu Beeinträchtigungen der Sehfunktionen geführt und eine Explantation erforderlich gemacht. Trotzdem sind weitere Forschungen, für die wir einige Ansätze vorschlagen, notwendig. Auch das Vorkommen von schwerwiegenden Trübungen bei anderen Kunstlinsentypen zeigt die Notwendigkeit für verstärkte Forschungen und gesetzliche Regulierungen auf diesem Gebiet. Insbesondere die hervorragend niedrigen Nachstarraten, die mit der Implantation von AcrySof®-Kunstlinsen einher gehen, berechtigen jedoch zu ihrer Weiterverwendung. Während es unwahrscheinlich scheint, daß die Glistenings noch schwerwiegende Probleme bereiten werden, so ist jedoch gesichert, daß durch die Verwendung von AcrySof®Kunstlinsen weniger YAG-Laser-Kapsulotomien notwendig sind. Daß sich damit auch die mit diesem Eingriff verbundenen Kosten und Komplikationen reduzieren ist selbstredend. Der Verlauf der Forschungen zu diesem Thema wird dargelegt. Die Notwendigkeit präziserer Studienaufbauten und besserer technischer Ausstattung wird deutlich. Durch den fortgeführten Einsatz der AcrySof®-IOL wurde die ophthalmologische Sichtweise der IOL verändert. Die IOL wird heute als Implantat betrachtet, welches die Aphakie korrigiert aber auch den Nachstar verhüten soll. Im kleinen Rahmen der Entwicklungsgeschichte der IOLs selbst, könnte dies den Beginn einer neuen IOL-Generation bedeuten.This study has been conducted to clarify the presence of microvacuoles within the optics of implanted AcrySof®-brand intraocular lenses (IOLs). These lenses were implanted in the Federal Republic of Germany, shortly after they became commercially available in December 1994. According to the manufacturing company, microvacuoles, also called glistenings, were caused by a new type of packaging which was used in the USA only. This situation led to explantations of IOLs and to the recall of lenses packed in that new manner. The main thrust of our fesearch program was the slitlamp examination of patients who had an implanted AcrySof®-lens. The findings were documented by means of slitlamp-photography. In addition, visual acuity tests were conducted. At the Same time, analog examinations and documentations of a second group of patients were done. These patients had been operated by the Same surgeon ,during the Same months as the patients of the AcrySof®-Group, but had common poly(methy1 methacry1ate)-I0Ls in their eyes. In all acrylic intraocular lenses microvacuoles could be found and documented. This phenomenon could not be Seen in any of the examined poly (methyl methacrylate)-IOLs. Our research also identified newer findings published by other investigators concerning the Acrysof®-IOL, We did not detect any signs of visual acuity reduction caused by the glistenings. Our literature search reveals that the glistenings have to be looked at as fluid uptake from the aqueus to the optic-body of the IOL. The fluid gathers in spaces within the polymer-structure of the IOL. The glistenings have a dimension of a few micrometers. Due to the different refractive indices of the content of the vacuoles and the IOL-material, the microvacuoles become visible as multiple pinpoint glistenings. Experimental work has shown that the formation of the glistenings increases with fluctuating temperature and the presence of serum. Some investigators have reported an increased prevalence of glistenings in patients who may have serum-components in the aqueus, caused by a compromised blood-aqueus-barrier or a compromised blood-retina-barrier, e. g. persons with diabetes. In this regard a reevaluation of our data showed signs of increased glistening-formation in above mentioned patients. The statement of the manufacturing company, that glistenings coincide with the packaging- and sterilisation of the IOLs with the new AcryPak-system, could be disproved by our results. The early literature in English shows a Consensus with the manufacturer's assertion. However, recent studies, referring to a poster presentation at the 1999 ASCRS meeting in Seattle, as the first publication of glistenings in commonly packed AcrySof®-IOLs, confirm our results. Earlier reports had been published by european authors, including our study-group. Although glistenings have resulted in very few explantations due to reduced visual accuity further research on this topic is necessary. Furthermore, the existence of severe opacities in other types of IOLs, suggests the necessity of increased research and legal regulation concerning this topic. The very low rates of posterior capsule opacification (PCO) following AcrySof®-IOLimplantations justify their use. While it is not likely that the glistenings will cause any severe problems, it is evident that implantation of AcrySof®-IOLs results in lower laser-capsulotomy-rates with a decreasing number of capsulotomy-associated complications and healthcare-cost-reduction. The Course of scientific research on the PCO-preventive effect of the AcrySof®-IOL is described in our discussion. We conclude that studies should be planned more precisely and should be conducted with equipment of higher technical standards. The continuous use of AcrySof®-IOLs changed the ophthalmologists' understanding of IOLs as such. Today the IOL is looked upon as an implant that corrects aphakia, but should also prevent PCO. From the perspective of the history of IOLs, this could mark the beginning of a new generation of IOL

The Role of Ethical Leadership in Psychological Capital and Job Satisfaction of Immigrant Workers: Evidence From the Hotel Industry of Cyprus

The goal of this research is to figure out the moderating act of ethical leadership on the effects of job satisfaction and psychological capital of employees. The Hotel industry in Northern Cyprus has been preferred with this respect. The study was conducted within the appropriate literature. Research-oriented data collection tools designed and used in accordance with the purposes of the research, research questions and hypotheses are surveyed. The findings of the study revealed the moderating role of ethical leadership (EL) on psychological capital (PsyCap) and job satisfaction (JS). It was also found that the participants were on the idea of working under equal conditions adopted via ethical leadership factors. The current study is a new era for the developmental issues of hospitality in terms of management and it is hoped that it will yield basic basements for further studies.publishedVersio

Further Increase in the Expression of Activation Markers on Monocyte-Derived Dendritic Cells in Coronary Artery Disease Patients with Ectasia Compared to Patients with Coronary Artery Disease Alone

Background. Coronary artery ectasia (CAE) is defined as localized or diffuse dilation of the coronary arteries. There are scarce data about the role of dendritic cells in CAE development. In this study we investigated the activation markers on the surface of monocyte-derived dendritic cells (mDCs) in coronary artery disease (CAD) patients with or without CAE. Method. The study consisted of 6 patients who had obstructive CAD with CAE, 6 CAD patients without CAE and 6 subjects with angiographically normal coronary arteries. mDCs were cultivated from peripheral blood monocytes. Surface activation markers were detected by flow cytometry. Results. CAD patients with CAE were detected to have significantly higher mean fluorescence intensities of CD11b, CD11c, CD54 , CD83, CD86 and MHC Class II molecules on mDCs in comparison to CAD patients without CAE and normal controls (P < .001 for all). A significant positive correlation was found between the number of vessels with CAE and the levels of CD11c, CD86, and MHC Class II molecules. Conclusion. mDCs display an increased cell surface concentration of activation molecules in CAD patients with CAE compared to patients with CAD alone. DC activation may play an important role for CAE development in patients with CAD

The Levels of Tumor Necrosis Factor-Alpha and Interleukin-6 in Patients with Isolated Coronary Artery Ectasia

Background/Aim. Coronary artery ectasia (CAE) is considered as a variant of atherosclerosis. Tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) are among the sensitive markers of systemic inflammation. The aim of this study was to evaluate the plasma levels of the cytokines; TNF-α and IL-6 in CAE patients. Methods. Plasma concentrations of TNF-α and IL-6 were measured in 36 patients with CAE (28 males, mean age: 58.2 ± 12 years), and results were compared with age and sex-matched controls (n = 32) without coronary artery ectasia. TNF-α and IL-6 concentrations in blood were assesed by enzyme-linked immunosorbent assay (ELISA). Results. Baseline characteristics of the two groups were similar. TNF-α and IL-6 levels were significantly higher in CAE group than controls (15.6 ± 11.2 pg/mL versus 7.8 ± 3.7 pg/mL, P < .001, and 17.2 ± 12.6 versus 7.6 ± 2.1 P < .0001, resp.). Conclusion. CAE patients showed increases in TNF-α and IL-6 levels compared to the controls. This study provides evidence for alterations in the proinflamatory cytokines which suggest the involvement of the immune system in the pathophysiology of CAE. Further placebo-controlled studies are needed to evaluate the clinical significance of this increase in TNF-α and IL-6 levels

Systems-level temporal immune-metabolic profile in Crimean-Congo hemorrhagic fever virus infection.

Crimean-Congo hemorrhagic fever (CCHF) caused by CCHF virus (CCHFV) is one of the epidemic-prone diseases prioritized by the World Health Organisation as public health emergency with an urgent need for accelerated research. The trajectory of host response against CCHFV is multifarious and remains unknown. Here, we reported the temporal spectrum of pathogenesis following the CCHFV infection using genome-wide blood transcriptomics analysis followed by advanced systems biology analysis, temporal immune-pathogenic alterations, and context-specific progressive and postinfection genome-scale metabolic models (GSMM) on samples collected during the acute (T0), early convalescent (T1), and convalescent-phase (T2). The interplay between the retinoic acid-inducible gene-I-like/nucleotide-binding oligomerization domain-like receptor and tumor necrosis factor signaling governed the trajectory of antiviral immune responses. The rearrangement of intracellular metabolic fluxes toward the amino acid metabolism and metabolic shift toward oxidative phosphorylation and fatty acid oxidation during acute CCHFV infection determine the pathogenicity. The upregulation of the tricarboxylic acid cycle during CCHFV infection, compared to the noninfected healthy control and between the severity groups, indicated an increased energy demand and cellular stress. The upregulation of glycolysis and pyruvate metabolism potentiated energy generation through alternative pathways associated with the severity of the infection. The downregulation of metabolic processes at the convalescent phase identified by blood cell transcriptomics and single-cell type proteomics of five immune cells (CD4+ and CD8+ T cells, CD14+ monocytes, B cells, and NK cells) potentially leads to metabolic rewiring through the recovery due to hyperactivity during the acute phase leading to post-viral fatigue syndrome

Cruise Travelers’ Service Perceptions: A Critical Content Analysis

This paper examines the main elements of online reviews left by popular cruise ships’ travelers. The eight most popular cruise ships were selected. We aimed to pinpoint the service quality experiential perceptions of cruise travelers regarding their higher or lower value for money ratings. Leximancer 4.5 software was used to derive the linkage and co-occurrence between service concepts in the online narratives of 2000 guests from Cruisecritic.com. The evaluation showed 10 areas addressed by the descriptions of the cruise’s perceived quality. These are “ship,” “staff,” “food,” “entertainment,” “room,” “area,” “embarkation,” “excursion” “disembarkation,” and “port.” Furthermore, the results highlight themes like “ship,” “staff,” “food,” “entertainment,” “room,” and “area” as belonging to the high-satisfaction group (excellent/very good), while “embarkation,” “disembarkation,” “excursion,” and “port” belong to the low-satisfaction group (poor/terrible). The study offers useful insights into cruise travelers’ general perceived experience according to user-generated content, and enables the identification of the main themes associated with different satisfaction groups.publishedVersio

Hearing the Voices of Wingless Angels: A Critical Content Analysis of Nurses' COVID-19 Experiences

The world has been affected by an outbreak of the novel coronavirus (COVID-19). Health care workers are among those most at risk of contracting the virus. In the fight against the coronavirus, nurses play a critical role. Still, most social media platforms demonstrate that nurses fear that their health is not being prioritized. The purpose of this study is to investigate nurses’ experiences through analyzing the main themes shared on Instagram by nurses during the COVID-19 pandemic. In contrast with highly structured research, the current paper highlights nurses’ natural language use in describing their experiences during the first months of the outbreak in their workplace. Instagram captions were utilized as a data source. Leximancer was utilized for the content analysis of nurses’ narratives towards their coronavirus experience. We sought to accomplish three research objectives: the first was to identify the main themes in the descriptions of nurses’ experiences shared via their social media, specifically Instagram; then, to determine the relationships among concepts, and finally, to give useful implications based on the findings. The current study uses a qualitative (i.e., narratives) approach to analyze the main components of the nurses’ experiences during the pandemic. The Leximancer software analysis revealed nine major textual themes and the relationships among these themes. In order of the relative importance, the themes were “patients”, “coronavirus”, “exhaustion”, “family”, “hospital”, “personal protective equipment” (PPE), “shift”, “fear”, and “uncertainty”. The results offer practical implications based on the social media information regarding nurses’ overall experiences.publishedVersio

Cruise Travelers’ Service Perceptions: A Critical Content Analysis

This paper examines the main elements of online reviews left by popular cruise ships’ travelers. The eight most popular cruise ships were selected. We aimed to pinpoint the service quality experiential perceptions of cruise travelers regarding their higher or lower value for money ratings. Leximancer 4.5 software was used to derive the linkage and co-occurrence between service concepts in the online narratives of 2000 guests from Cruisecritic.com. The evaluation showed 10 areas addressed by the descriptions of the cruise’s perceived quality. These are “ship,” “staff,” “food,” “entertainment,” “room,” “area,” “embarkation,” “excursion” “disembarkation,” and “port.” Furthermore, the results highlight themes like “ship,” “staff,” “food,” “entertainment,” “room,” and “area” as belonging to the high-satisfaction group (excellent/very good), while “embarkation,” “disembarkation,” “excursion,” and “port” belong to the low-satisfaction group (poor/terrible). The study offers useful insights into cruise travelers’ general perceived experience according to user-generated content, and enables the identification of the main themes associated with different satisfaction groups

Air-Travelers’ Perceptions of Service Quality during the COVID-19 Pandemic: Evidence from Tripadvisor Sites

The COVID-19 pandemic has impacted both healthcare and the economy on a global scale. This pandemic has changed consumer habits and behaviors significantly, primarily because of confinement-related issues. While numerous research has been undertaken to study customer satisfaction using surveys and online passenger ratings, the effect of COVID-19 on passenger satisfaction has not been explored. It is vital to assess satisfaction indicators gathered from online consumer reviews to ascertain consumers’ preferences for airline services during the COVID-19 pandemic. The goal of this study is to determine the primary themes that emerged from airline travelers’ internet reviews during the COVID-19 outbreak. Additionally, it attempts to determine which of these themes relate to higher and lower passenger satisfaction. The article uses qualitative (i.e., narratives) analyses to examine the main components of passengers’ subjective experiences of the airline. Data are represented by passenger reviews posted on the TripAdvisor website. The analyses revealed ten themes in descriptions of airline travel experiences. These include “flight”, “service”, “staff”, “food”, “check-in”, “cancellation”, “COVID-19”, “airport”, “class”, and “luggage”. Dissatisfying concepts are linked with the “cancellation”, “check-in”, “refund”, and “airport” concepts

Air-Travelers&rsquo; Perceptions of Service Quality during the COVID-19 Pandemic: Evidence from Tripadvisor Sites

The COVID-19 pandemic has impacted both healthcare and the economy on a global scale. This pandemic has changed consumer habits and behaviors significantly, primarily because of confinement-related issues. While numerous research has been undertaken to study customer satisfaction using surveys and online passenger ratings, the effect of COVID-19 on passenger satisfaction has not been explored. It is vital to assess satisfaction indicators gathered from online consumer reviews to ascertain consumers&rsquo; preferences for airline services during the COVID-19 pandemic. The goal of this study is to determine the primary themes that emerged from airline travelers&rsquo; internet reviews during the COVID-19 outbreak. Additionally, it attempts to determine which of these themes relate to higher and lower passenger satisfaction. The article uses qualitative (i.e., narratives) analyses to examine the main components of passengers&rsquo; subjective experiences of the airline. Data are represented by passenger reviews posted on the TripAdvisor website. The analyses revealed ten themes in descriptions of airline travel experiences. These include &ldquo;flight&rdquo;, &ldquo;service&rdquo;, &ldquo;staff&rdquo;, &ldquo;food&rdquo;, &ldquo;check-in&rdquo;, &ldquo;cancellation&rdquo;, &ldquo;COVID-19&rdquo;, &ldquo;airport&rdquo;, &ldquo;class&rdquo;, and &ldquo;luggage&rdquo;. Dissatisfying concepts are linked with the &ldquo;cancellation&rdquo;, &ldquo;check-in&rdquo;, &ldquo;refund&rdquo;, and &ldquo;airport&rdquo; concepts