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Human cornea construct HCC-an alternative for in vitro permeation studies? A comparison with human donor corneas. 总被引:1,自引:0,他引:1
Stephan Reichl Stefanie D?hring Jürgen Bednarz Christel C Müller-Goymann 《European journal of pharmaceutics and biopharmaceutics》2005,60(2):305-308
Transcorneal in vitro permeation studies of ophthalmic drugs are normally performed with either excised animal corneas or latterly corneal cell culture models. A good correlation between these models and excised animal corneas regarding permeation behaviour of drugs has already been shown. However, comparisons between corneal in vitro models containing human cells and excised human corneas do not exist yet. Therefore in the present study the transcorneal permeation of six different model drugs (pilocarpine hydrochloride, befunolol hydrochloride, hydrocortisone, diclofenac sodium, clindamycin hydrochloride and timolol maleate) across our previously described three-dimensional organotypic human cornea construct (HCC) was tested using Franz diffusion cells and compared with permeation data obtained from human donor corneas. The HCC showed a similar permeation behaviour compared with human donor cornea for all substances. The permeabilities (permeation coefficients P) of the human cornea equivalent versus the human donor cornea were the same in the case of diclofenac, clindamycin, timolol, but marginally decreased for hydrocortisone and slightly increased for pilocarpine and befunolol. These small differences of permeation coefficients were expressed as factors and only varied from 0.8 to 1.4. The results indicate that the HCC may be an alternative for in vitro permeation studies and appropriate for predicting drug absorption into the human eye. 相似文献
23.
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
24.
Stefanie M. Croghan Niall Compton Rustom P. Manecksha Ivor M. Cullen Pdraig J. Daly 《Canadian Urological Association journal》2022,16(5):E287
IntroductionGrowing interest surrounds the concept of en bloc transurethral resection of bladder tumors (ERBT). Theoretical advantages include improved adherence to oncological principles and potential yield of superior pathological specimens. Multiple ERBT methods exist. This review summarizes the current evidence regarding application of differing techniques and technologies to ERBT.MethodsA systematic review of MEDLINE/EMBASE/Scopus databases was performed, using terms “en bloc,” “ERBT,” “bladder,” and “urinary bladder neoplasm.” Template-based data extraction included technique of ERBT, feasibility, tumor size, activation of obturator nerve reflex, operative complications, detrusor muscle sampling rate, and recurrence data.ResultsMultiple approaches to ERBT have evolved, using a variety of energy sources. The feasibility of electrocautery, laser, combined waterjet/electrocautery, and polypectomy snare techniques have been confirmed in achieving ERBT. ERBT appears safe, with a low complication rate. The use of laser energy sources reduces the risk of activating the obturator nerve reflex during lateral wall resections. Otherwise, no energy source is unequivocally superior in achieving ERBT. The rate of detrusor muscle sampling is high with use of ERBT and appears superior to that achieved with conventional TURBT (cTURBT) in multiple comparative studies. A limited number of largely non-randomized trials assess bladder tumor recurrence; current evidence suggests this is similar between ERBT and cTURBT groups.ConclusionsERBT using a variety of technologies is feasible and safe, with a high detrusor muscle sampling rate. Further research is required to determine whether rates of residual disease or recurrence can be reduced with ERBT vs. cTURBT. 相似文献
25.
Rita K. Schmutzler Bjrn Schmitz-Luhn Bettina Borisch Peter Devilee Diana Eccles Per Hall Judith Balmaa Stefania Boccia Peter Dabrock Günter Emons Wolfgang Gaissmaier Jacek Gronwald Stefanie Houwaart Stefan Huster Karin Kast Alexander Katalinic Sabine C. Linn Sowmiya Moorthie Paul Pharoah Kerstin Rhiem Tade Spranger Dominique Stoppa-Lyonnet Johannes Jozef Marten van Delden Marc van den Bulcke Christiane Woopen 《Breast care (Basel, Switzerland)》2022,17(2):208
BackgroundRisk-adjusted cancer screening and prevention is a promising and continuously emerging option for improving cancer prevention. It is driven by increasing knowledge of risk factors and the ability to determine them for individual risk prediction. However, there is a knowledge gap between evidence of increased risk and evidence of the effectiveness and efficiency of clinical preventive interventions based on increased risk. This gap is, in particular, aggravated by the extensive availability of genetic risk factor diagnostics, since the question of appropriate preventive measures immediately arises when an increased risk is identified. However, collecting proof of effective preventive measures, ideally by prospective randomized preventive studies, typically requires very long periods of time, while the knowledge about an increased risk immediately creates a high demand for action.SummaryTherefore, we propose a risk-adjusted prevention concept that is based on the best current evidence making needed and appropriate preventive measures available, and which is constantly evaluated through outcome evaluation, and continuously improved based on these results. We further discuss the structural and procedural requirements as well as legal and socioeconomical aspects relevant for the implementation of this concept. 相似文献
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Stefanie Wessely Marc Tappiser Nina Eisenburger Sven Feddern Andreas Gehlhar Anna Kilimann Lisa Klee Johannes Nießen Nikola Schmidt Gerhard A. Wiesmüller Annelene Kossow Barbara Grüne Christine Joisten 《Obesity facts》2022,15(4):570
IntroductionPublic health measures enacted to reduce COVID-19 transmission have affected individuals'' lifestyles, mental health, and psychological well-being. To date, little is known how stay-at-home orders have influenced the eating behaviors, weight development, and alcohol consumption of quarantined persons. The CoCo-Fakt cohort study analyzed these parameters and their association with psychological distress and coping strategies.MethodsAn online survey was conducted of all persons who tested positive for SARS-CoV-2 (infected persons [IP]) between December 12, 2020, and January 6, 2021, as well as their close contacts (contact persons [CP]) registered by the public health department of Cologne. 8,075 of 33,699 individuals were included in the analysis. In addition to demographic data, psychological distress, and coping strategies, information on changes in body weight, eating, and drinking behaviors was collected.ResultsIP lost 1.2 ± 4.4 kg during the quarantine period, and CP gained 1.6 ± 4.1 kg. The reasons given by IP for weight change were mainly loss of taste and feeling sick, whereas CP were more likely than IP to eat out of boredom. Higher psychological burden and lower coping strategies were associated with both weight gain and loss. Of the 30.8% of participants who changed their alcohol consumption during the quarantine period, CP in particular drank more alcohol (IP 15.2%; CP 47.7%). Significantly less alcohol was consumed by individuals with higher coping scores.ConclusionIn this short but psychologically stressful period of stay-at-home orders, changes in eating and drinking behavior as well as weight development are evident, mainly in high-risk contacts. To avoid possible long-term sequelae, health authorities should take these findings into account during the quarantine period; in particular, general practitioners should consider these findings during follow-up. 相似文献
28.
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
29.
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