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41.
Florian Painer Andre Baldermann Florian Gallien Stefanie Eichinger Florian Steindl Reiner Dohrmann Martin Dietzel 《Materials》2022,15(13)
The hydrothermal alteration of perlite into zeolites was studied using a two-step approach. Firstly, perlite powder was transformed into Na-P1 (GIS) or hydro(xy)sodalite (SOD) zeolites at 100 °C and 24 h using 2 or 5 M NaOH solutions. Secondly, the Si:Al molar ratio of the reacted Si-rich solution was adjusted to 1 by Na-aluminate addition to produce zeolite A (LTA) at 65 or 95 °C and 6 or 24 h at an efficiency of 90 ± 9% for Al and 93 ± 6% for Si conversion. The performance of these zeolites for metal ion removal and water softening applications was assessed by sorption experiments using an artificial waste solution containing 4 mmol/L of metal ions (Me2+: Ca2+, Mg2+, Ba2+ and Zn2+) and local tap water (2.1 mmol/L Ca2+ and 0.6 mmol/L Mg2+) at 25 °C. The removal capacity of the LTA-zeolite ranged from 2.69 to 2.86 mmol/g for Me2+ (=240–275 mg/g), which is similar to commercial zeolite A (2.73 mmol/g) and GIS-zeolite (2.69 mmol/g), and significantly higher compared to the perlite powder (0.56 mmol/g) and SOD-zeolite (0.88 mmol/g). The best-performing LTA-zeolite removed 99.8% Ca2+ and 93.4% Mg2+ from tap water. Our results demonstrate the applicability of the LTA-zeolites from perlite for water treatment and softening applications. 相似文献
42.
43.
Shqipdona Lahu Peter Bristot Senta Gewalt Alexander Goedel Daniele Giacoppo Stefanie Schüpke Heribert Schunkert Adnan Kastrati Nikolaus Sarafoff 《Journal of atherosclerosis and thrombosis》2022,29(7):1001
Aim: The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is an ongoing debate and novel data has emerged. The aim of this meta-analysis was to assess outcomes of short vs. control DAPT duration. In addition, the role of single antiplatelet therapy (SAPT) after DAPT with either aspirin or P2Y12 inhibitor monotherapy was analyzed. Methods: The authors searched MEDLINE and Cochrane databases and proceedings of international meetings for randomized controlled trials (RCT) comparing ≤ 3 months with ≥ 6 months DAPT after DES implantation. The primary and co-primary outcomes of interest were definite or probable stent thrombosis (ST) and bleeding. In addition, we performed an analysis on studies who continued with either aspirin or P2Y12 monotherapy after DAPT. Results: 9 RCTs comprising 41,864 patients were included and we analyzed a short DAPT duration of median 1.5 months vs. 12.1 months in the control group. The risk for ST was similar with short vs. control DAPT duration (0.5 vs. 0.5%; hazard ratio 1.17[95% CI 0.89-1.54];p=0.26). Bleeding was significantly reduced with short vs. control DAPT duration (1.9 vs. 3.0%; 0.65[0.54-0.77];p<0.0001). ST was not different between short vs. control DAPT duration in the analysis of the 4 RCTs who continued with aspirin after DAPT and the 5 P2Y12 RCTs, respectively, and no heterogeneity was detected (p=0.861). Bleeding was also reduced with short vs. control DAPT in both the aspirin (1.2 vs. 1.7%; 0.71[0.51-0.99];p=0.04) and P2Y12 inhibitor studies (2.1 vs. 3.4%; 0.62[0.47-0.80];p=0.0003) and no heterogeneity was detected (p=0.515). Conclusions: Our meta-analysis shows that short DAPT ≤ 3 months followed by SAPT reduces bleeding and is not associated with an increase in ST. The results were consistent within the aspirin and P2Y12 SAPT studies. 相似文献
44.
Raisuke Iijima MD Gjin Ndrepepa MD Julinda Mehilli MD Franz-Josef Neumann MD Stefanie Schulz MD Jurriën ten Berg MD Olga Bruskina MD Franz Dotzer MD Josef Dirschinger MD Peter B. Berger MD Albert Schömig MD Adnan Kastrati MD 《Clinical research in cardiology》2008,97(3):160-168
Objective We investigated how does troponin level (TnT) affect the benefit achieved by abciximab in patients with acute coronary syndromes
(ACS) undergoing percutaneous coronary intervention (PCI) after pretreatment with a high loading dose of clopidogrel.
Methods The Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment (ISAR-REACT 2) trial included
2,022 patients with non-ST elevation ACS undergoing PCI who were randomized to abciximab or placebo after pretreatment with
600 mg of clopidogrel. The patients were divided into groups with elevated TnT level (n = 1,049) and no elevated TnT level (n = 973). The primary end point of the trial was the composite of death, myocardial infarction and urgent reintervention at
30 days.
Results In patients with elevated TnT level the incidence of the primary end point was 13.1% in the abciximab group Vs. 18.3% in the
placebo group [relative risk (RR): 0.70; 95% confidence interval (CI), 0.52–0.95, P = 0.02]. The combined incidence of death or myocardial infarction was 12.9% in the abciximab group vs. 17.9% in the placebo
group (RR: 0.71; 95% CI, 0.52–0.96, P = 0.03). In contrast, the incidence of the primary end point in patients with no elevated TnT level was identical in both
treatment groups (4.6%). The risk of bleeding was not related to TnT level.
Conclusions Baseline troponin level affects the benefit of abciximab in patients with ACS undergoing PCI after pretreatment with a high
loading dose of clopidogrel. Abciximab reduces the risk of ischemic events only in patients with ACS and elevated troponin
level. 相似文献
45.
Ju-Hyeong Park Eungul Lee Ethan D. Fechter-Leggett Ellie Williams Shobha Yadav Arundhati Bakshi Stefanie Ebelt Jesse E. Bell Heather Strosnider Ginger L. Chew 《Environmental health perspectives》2022,130(8)
Background: Studies of thunderstorm asthma to understand risk factors using high-resolution climate data and asthma outcomes on a large scale are scarce. Moreover, thunderstorm asthma is not well studied in the United States.Objectives: We examined whether climate parameters involved in thunderstorms are associated with emergency department (ED) visits for acute asthma attacks in the United States.Methods: We analyzed 63,789 asthma-related, daily ED visits for all age groups, and thunderstorm-associated climate data in Louisiana during 2010 through 2012. We performed time-series analyses using quasi-Poisson regression models with natural cubic splines of date, parish, holiday, day of week, season, daily maximum concentrations of ozone () and fine particulate matter [PM in aerodynamic diameter ()], and daily mean pressure, precipitation, and temperature. Because of a significant interaction effect between temperature and lightning days on asthma-related visits, we performed stratified analyses by days with/without lightning or thunderstorm (defined by any lightning and precipitation).Results: On thunderstorm days, higher asthma-related ED visits were associated with higher daily mean precipitation [ (95% CI: 1.009, 1.300)] and lower daily mean temperature [ per 1°C change (1.000–1.021)] without carry-over effect to the next non-thunderstorm day. These higher risks were found mainly among children and adults of age. We observed similar results on lightning days. However, we did not find similar associations for non-thunderstorm or non-lightning days. Daily maximum and levels were not significantly associated with asthma ED visits on thunderstorm days.Discussion: Higher precipitation and lower temperature on thunderstorm days appear to contribute to asthma attacks among people with asthma, suggesting they should consider taking precautions during thunderstorms. EDs should consider preparing for a potential increase of asthma-related visits and ensuring sufficient stock of emergency medication and supplies for forecasted severe thunderstorm days. https://doi.org/10.1289/ EHP10440相似文献
46.
Sara Denicolò Paul Perco Stefanie Thöni Gert Mayer 《Journal of diabetes and its complications》2021,35(7):107931
Cardiovascular and renal complications are a major burden for individuals with type 2 diabetes mellitus (T2DM). Besides lifestyle interventions, current guidelines recommend combination drug therapy to prevent or delay the incidence and progression of comorbidities. However, non-adherence to pharmacotherapy is common in chronic conditions such as T2DM and a barrier to successful disease management. Numerous studies have associated medication non-adherence with worse outcome as well as higher health care costs. This narrative review provides (i) an overview on adherence measures used within and outside research settings, (ii) an estimate on the prevalence of non-adherence to antidiabetic and cardiovascular drugs in T2DM, and (iii) specifically focuses on the association of non-adherence to these drugs with renal and cardiovascular outcomes. 相似文献
47.
Schemm Stefanie A. Schemm Andreas Schwenkhagen Anneliese Schaudig Katrin 《Der Gyn?kologe》2019,52(6):463-472
Die Gynäkologie - Frauen im Erwachsenenalter mit einem angeborenen Herzfehler (EMAH) werden in Zukunft aufgrund des medizinischen Fortschritts eine immer größere Patientinnengruppe... 相似文献
48.
Jessica L. Cromheecke Kathleen T. Nguyen David P. Huston 《Current allergy and asthma reports》2014,14(1):1-9
Basophils have emerged in recent years as a small but potent subpopulation of leukocytes capable of bridging innate and adaptive immunity. They can be activated through IgE-dependent and IgE-independent mechanisms to release preformed mediators and to produce Th2 cytokines. In addition to their role in protective immunity to helminths, basophils are major participants in allergic reactions as diverse as anaphylaxis and immediate hypersensitivity reactions, late-phase hypersensitivity reactions, and delayed hypersensitivity reactions. Additionally, basophils have been implicated in the pathophysiology of autoimmune diseases such as lupus nephritis and rheumatoid arthritis, and the modulation of immune responses to bacterial infections, as well as being a feature of myelogenous leukemias. Distinct signals for activation, degranulation, transendothelial migration, and immune regulation are being defined, and demonstrate the important role of basophils in promoting a Th2 microenvironment. These mechanistic insights are driving innovative approaches for diagnostic testing and therapeutic targeting of basophils. 相似文献
49.
Johannes Hohenberger Anton Friesen Stefanie Wieck Klaus Kümmerer 《Sustainable Chemistry and Pharmacy》2022
The field of chemical rodent control has seen no major developments in the last decades, even though anticoagulant rodenticides (AR), the mainly used substances to manage mice and rats, are known environmental pollutants and candidates for substitution under the European Biocidal Products Regulation 528/2012. Moreover, recent political developments in Europe and the USA demand more safety and sustainability in the management of chemicals, reinforcing the need for environmentally friendly substances. In this concept study, we present a step-by-step approach to improve the environmental properties of rodenticides. Repurposing of existing pharmaceuticals, the use of enantiomerically pure rodenticides, or the improvement of the formulation by microencapsulation can help to alleviate environmental problems caused by AR in the short term. Modification of the chemical structures or the development of prodrugs as medium-term strategies can further improve environmental properties of existing compounds. Ultimately, the development of new substances from scratch enables the utilisation of so far ignored modes of actions and the application of modern safe and sustainable-by-design principles to improve target specificity and reduce the negative impact on non-target organisms and the environment. Overall, our concept study illustrates the great potential for improvement in the field of chemical rodent control when applying available techniques of green and sustainable chemistry to known or potential rodenticides. Most promising in the medium term is microencapsulation that would allow for the use of acutely acting substances as it could circumvent bait shyness. On a longer timescale the de novo design of new rodenticides, which is the only method that can combine a high target specificity with good environmental properties, is the most promising approach. 相似文献
50.