113 research outputs found

    External beam radiation after stent implantation increases neointimal hyperplasia by augmenting smooth muscle cell proliferation and extracellular matrix accumulation

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    AbstractOBJECTIVESWe sought to examine the effects of high volume external beam radiation (EBR) after stent implantation on neointimal hyperplasia, smooth muscle cell (SMC) proliferation, presence of inflammatory cells and expression of extracellular matrix (ECM).BACKGROUNDEndovascular irradiation has been shown to reduce restenosis rates after angioplasty in preliminary trials, but conflicting results have been reported for the effects of external beam irradiation.METHODSForty-three Palmaz-Schatz stents were implanted into iliac arteries of New Zealand White rabbits. The arteries were externally irradiated after stent implantation with a single dose of 8 Gy (at day 3) or 16 Gy in two fractions (8 Gy at days 3 and 4) by means of a linear accelerator. In the control rabbits, no radiation was applied after stent implantation. Smooth muscle cells, macrophages and ECM were studied by immunohistochemistry at one and 12 weeks after stent implantation. Collagen type I and biglycan messenger ribonucleic acid (mRNA) levels were assessed by Northern blot analysis at one week. Neointimal cell densities and arterial lumen stenosis were measured by histomorphometry at 12 weeks.RESULTSAt 1 week, SMC proliferation at the site of stent implantation was increased after EBR with 8 and 16 Gy (26 ± 5%, 32 ± 3% vs. 17 ± 8%; p < 0.01, 16 Gy vs. control). External beam radiation with 8 and 16 Gy augmented SMC proliferation proximal and distal to the angioplasty site (11 ± 3%, 14 ± 3 vs. 6 ± 1%; p < 0.01, 16 Gy vs. control). Collagen type I and biglycan mRNA levels were elevated in stented arteries after EBR with 16 Gy. At 12 weeks, a marked decrease in neointimal cell density (248 ± 97 vs. 498 ± 117 SMCs/0.1 mm2neointima; p < 0.005 vs. control) was noted after EBR with 16 Gy. Irradiation with 8 and 16 Gy increased arterial lumen stenosis compared with nonirradiated control rabbits (45 ± 7%, 55 ± 9% vs. 33 ± 7%; p < 0.05, 8 Gy and p < 0.001, 16 Gy vs. control).CONCLUSIONSHigh volume external beam radiation at doses of 8 or 16 Gy causes restenosis by augmenting proliferative activity at and adjacent to the site of stent implantation, and by dose-dependent up-regulation of extracellular matrix expression. The study suggests that excessive matrix accumulation is an important determinant of failure of radiation therapy to prevent restenosis

    Impact of COVID-19 on Aviation-Wildlife Strikes Across Europe

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    Collisions between aircraft and wildlife (i.e., wildlife strikes) pose a serious threat toward the safety of aircraft, its crew, and passengers. The effects of COVID-19 related travel restrictions on wildlife strikes are unknown. With this study, we aim to address this information gap by assessing the changes of wildlife hazard management performance across European airports during the lockdown period (e.g., period of reduced operations and borders closure in spring 2020). We also sought to raise awareness of the importance of wildlife strike prevention in times of reduced operations. The objective of our study was to compare wildlife strike data before and during the lockdown based on the following criteria: (1) the number of wildlife strikes per 10,000 flights, (2) the groups of wildlife species involved, and (3) the lighting conditions. To conduct our research, we analyzed a dataset of 12,528 wildlife strikes, gathered from 157 civil airports across Europe for the period from March 2017 to February 2021. Our analysis revealed a wide variation in the wildlife strike rates during the lockdown (period of time from March 1, 2020 to February 28, 2021). Our study uncovered an increasing trend of the relative strike rates for almost all wildlife species categories and a slight trend toward more strikes occurring during daytime compared to nighttime. Our findings highlighted the need for continuous wildlife hazard management despite fluctuation in flights and provide potential for airports, airline operators, and other aviation stakeholders to reduce wildlife strike risk

    histat - Zeitreihen zur Historischen Statistik von Deutschland online: Aufbau, Inhalt, Aufbereitung, technische Umsetzung

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    Der Datenservice Historische Studien ist Teil des Datenarchivs für Sozialwissenschaften (DAS). Der Studien- und Datenbestand dieses Bereiches zeichnet sich durch eine hohe Qualität aus. Einen bedeutenden Schwerpunkt bilden Studien mit Zeitreihendaten. Sie stellen mittlerweile 70% des gesamten historischen Studienbestandes. Um der interessierten Öffentlichkeit einen komfortablen Zugang zu diesem umfangreichen Zeitreihen-Datenbestand zu bieten, wurde die Online-Datenbank histat von GESIS entwickelt und seit 2004 auf den GESIS-Seiten zugänglich gemacht. Zwischenzeitlich liegt histat in seiner 5. Version vor. Der vorliegende Report soll den Entstehungszusammenhang von histat erläutern, in die Menü-Führung einführen und Einblicke in das Prozedere der Datenaufbereitung für histat -Studien geben. Darüber hinaus wird die technische Struktur der Datenbank vorgestellt.The Data Service of Historical Studies is part of the Data Archive for Social Sciences (DAS). Data of historical studies are characterized by a high quality of the collected data. In the meantime the portion of studies with time series is about 70% of all historical studies. Therefore they became an important focus of the historical data collection. In order to offer a comfortable access to this comprehensive inventory of time series for the interested public, the online-database histat was developed by GESIS and published since 2004 via the GESIS-Web. Over the intervening years 5 versions of histat has been published. The report at hand deals with the context in which the database histat was created. Furthermore, an introduction to the menu navigation and a remarkable insight into the procedure of data preparation and processing according to archival standards is given. Additional we provide information on the technical structure of the data base

    Antibiotic therapeutic drug monitoring in intensive care patients treated with different modalities of extracorporeal membrane oxygenation (ECMO) and renal replacement therapy: a prospective, observational single-center study

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    Background: Efective antimicrobial treatment is key to reduce mortality associated with bacterial sepsis in patients on intensive care units (ICUs). Dose adjustments are often necessary to account for pathophysiological changes or renal replacement therapy. Extracorporeal membrane oxygenation (ECMO) is increasingly being used for the treatment of respiratory and/or cardiac failure. However, it remains unclear whether dose adjustments are necessary to avoid subtherapeutic drug levels in septic patients on ECMO support. Here, we aimed to evaluate and comparatively assess serum concentrations of continuously applied antibiotics in intensive care patients being treated with and without ECMO. Methods: Between October 2018 and December 2019, we prospectively enrolled patients on a pneumological ICU in southwest Germany who received antibiotic treatment with piperacillin/tazobactam, ceftazidime, meropenem, or linezolid. All antibiotics were applied using continuous infusion, and therapeutic drug monitoring of serum concentrations (expressed as mg/L) was carried out using high-performance liquid chromatography. Target concentrations were defned as fourfold above the minimal inhibitory concentration (MIC) of susceptible bacterial isolates, according to EUCAST breakpoints

    TNF-related apoptosis-inducing ligand, interferon gamma-induced protein 10, and C-reactive protein in predicting the progression of SARS-CoV-2 infection : a prospective cohort study

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    Background: Early prognostication of COVID-19 severity will potentially improve patient care. Biomarkers, such as TNF-related apoptosis-inducing ligand (TRAIL), interferon gamma-induced protein 10 (IP-10), and C-reactive protein (CRP), might represent possible tools for point-of-care testing and severity prediction. Methods: In this prospective cohort study, we analyzed serum levels of TRAIL, IP-10, and CRP in patients with COVID-19, compared them with control subjects, and investigated the association with disease sever ity. Results: A total of 899 measurements were performed in 132 patients (mean age 64 years, 40.2% females). Among patients with COVID-19, TRAIL levels were lower (49.5 vs 87 pg/ml, P = 0.0142), whereas IP-10 and CRP showed higher levels (667.5 vs 127 pg/ml, P <0.001; 75.3 vs 1.6 mg/l, P <0.001) than healthy controls. TRAIL yielded an inverse correlation with length of hospital and intensive care unit (ICU) stay, Simplified Acute Physiology Score II, and National Early Warning Score, and IP-10 showed a positive cor relation with disease severity. Multivariable regression revealed that obesity (adjusted odds ratio [aOR] 5.434, 95% confidence interval [CI] 1.005-29.38), CRP (aOR 1.014, 95% CI 1.002-1.027), and peak IP-10 (aOR 1.001, 95% CI 1.00-1.002) were independent predictors of in-ICU mortality

    Ligelizumab for Chronic Spontaneous Urticaria

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    Background: In the majority of patients with chronic spontaneous urticaria, most currently available therapies do not result in complete symptom control. Ligelizumab is a next-generation high-affinity humanized monoclonal anti-IgE antibody. Data are limited regarding the dose–response relationship of ligelizumab and the efficacy and safety of ligelizumab as compared with omalizumab and placebo in patients who have moderate-to-severe chronic spontaneous urticaria that is inadequately controlled with H1-antihistamines at approved or increased doses, alone or in combination with H2-antihistamines or leukotriene-receptor antagonists. Methods: In a phase 2b dose-finding trial, we randomly assigned patients to receive ligelizumab at a dose of 24 mg, 72 mg, or 240 mg, omalizumab at a dose of 300 mg, or placebo, administered subcutaneously every 4 weeks for a period of 20 weeks, or a single 120-mg dose of ligelizumab. Disease symptoms of hives, itch, and angioedema were monitored by means of weekly activity scores. The main objective was to determine a dose–response relationship for the complete control of hives (indicated by a weekly hives-severity score of 0, on a scale from 0 to 21, with higher scores indicating greater severity); the primary end point of this response was assessed at week 12. Complete symptom control was indicated by a weekly urticaria activity score of 0 (on a scale from 0 to 42, with higher scores indicating greater severity). Safety was analyzed throughout the trial. Results: A total of 382 patients underwent randomization. At week 12, a total of 30%, 51%, and 42% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of hives, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. A dose–response relationship was established. At week 12, a total of 30%, 44%, and 40% of the patients treated with 24 mg, 72 mg, and 240 mg, respectively, of ligelizumab had complete control of symptoms, as compared with 26% of the patients in the omalizumab group and no patients in the placebo group. In this small and short trial, no safety concerns regarding ligelizumab or omalizumab emerged. Conclusions: A higher percentage of patients had complete control of symptoms of chronic spontaneous urticaria with ligelizumab therapy of 72 mg or 240 mg than with omalizumab or placebo. (Funded by Novartis Pharma; ClinicalTrials.gov number, NCT02477332. opens in new tab.

    IgE Mediated Autoallergy against Thyroid Peroxidase – A Novel Pathomechanism of Chronic Spontaneous Urticaria?

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    Chronic spontaneous urticaria (csU), which is characterized by recurrent episodes of mast cell-driven wheal and flare-type skin reactions, is often associated with elevated total IgE levels and thyroid autoimmunity. We speculate that some csU patients express IgE autoantibodies against thyroid antigens such as thyroid peroxidase (TPO), which could bind to skin mast cells and induce their activation.We developed and used a site-directed human IgE capture ELISA to quantify IgE-anti-TPO. We used this assay and investigated csU patients (n = 478) and healthy control subjects (n = 127) for IgE-anti-TPO and then assessed IgE-anti-TPO-positive and -negative csU patients for clinical and serological differences. ( = 61%, IgE-anti-TPO: median 6.67, interquartile range 5.39–8.24). IgE-anti-TPO-positive and -negative csU patients had very similar distributions of age and gender as well as disease activity and duration. IgE-anti-TPO-positive csU patients exhibited significantly higher IgG-anti-TPO levels and lymphocyte counts as well as decreased C4 complement levels.Our findings show that a sizeable subgroup of csU patients expresses IgE antibodies against thyroid peroxidase. These autoantibodies could cause “autoallergic” mast cell activation, a novel pathomechanism of chronic spontaneous urticaria

    Morphological brain differences between adult stutterers and non-stutterers

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    BACKGROUND: The neurophysiological and neuroanatomical foundations of persistent developmental stuttering (PDS) are still a matter of dispute. A main argument is that stutterers show atypical anatomical asymmetries of speech-relevant brain areas, which possibly affect speech fluency. The major aim of this study was to determine whether adults with PDS have anomalous anatomy in cortical speech-language areas. METHODS: Adults with PDS (n = 10) and controls (n = 10) matched for age, sex, hand preference, and education were studied using high-resolution MRI scans. Using a new variant of the voxel-based morphometry technique (augmented VBM) the brains of stutterers and non-stutterers were compared with respect to white matter (WM) and grey matter (GM) differences. RESULTS: We found increased WM volumes in a right-hemispheric network comprising the superior temporal gyrus (including the planum temporale), the inferior frontal gyrus (including the pars triangularis), the precentral gyrus in the vicinity of the face and mouth representation, and the anterior middle frontal gyrus. In addition, we detected a leftward WM asymmetry in the auditory cortex in non-stutterers, while stutterers showed symmetric WM volumes. CONCLUSIONS: These results provide strong evidence that adults with PDS have anomalous anatomy not only in perisylvian speech and language areas but also in prefrontal and sensorimotor areas. Whether this atypical asymmetry of WM is the cause or the consequence of stuttering is still an unanswered question

    Contrasting disease patterns in seropositive and seronegative neuromyelitis optica: A multicentre study of 175 patients

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    BACKGROUND: The diagnostic and pathophysiological relevance of antibodies to aquaporin-4 (AQP4-Ab) in patients with neuromyelitis optica spectrum disorders (NMOSD) has been intensively studied. However, little is known so far about the clinical impact of AQP4-Ab seropositivity. OBJECTIVE: To analyse systematically the clinical and paraclinical features associated with NMO spectrum disorders in Caucasians in a stratified fashion according to the patients' AQP4-Ab serostatus. METHODS: Retrospective study of 175 Caucasian patients (AQP4-Ab positive in 78.3%). RESULTS: Seropositive patients were found to be predominantly female (p 1 myelitis attacks in the first year were identified as possible predictors of a worse outcome. CONCLUSION: This study provides an overview of the clinical and paraclinical features of NMOSD in Caucasians and demonstrates a number of distinct disease characteristics in seropositive and seronegative patients
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