The first full‐color polymer organic light‐emitting diode (OLED) display is reported, fabricated by a direct photolithography process, that is, a process that allows direct structuring of the ...electroluminescent layer of the OLED by exposure to UV light. The required photosensitivity is introduced by attaching oxetane side groups to the backbone of red‐, green‐, and blue‐light‐emitting polymers. This allows for the use of photolithography to selectively crosslink thin films of these polymers. Hence the solution‐based process requires neither an additional etching step, as is the case for conventional photoresist lithography, nor does it rely on the use of prestructured substrates, which are required if ink‐jet printing is used to pixilate the emissive layer. The process allows for low‐cost display fabrication without sacrificing resolution: Structures with features in the range of 2 μm are obtained by patterning the emitting polymers via UV illumination through an ultrafine shadow mask. Compared to state‐of‐the‐art fluorescent OLEDs, the display prototype (pixel size 200 μm × 600 μm) presented here shows very good efficiency as well as good color saturation for all three colors. The application in solid‐state lighting is also possible: Pure white light Commision Internationale de l'Éclairage (CIE) values of 0.33, 0.33 and color rendering index (CRI) of 76 is obtained at an efficiency of 5 cd A–1 by mixing the three colors in the appropriate ratio. For further enhancement of the device efficiency, an additional hole‐transport layer (HTL), which is also photo‐crosslinkable and therefore suitable to fabricate multilayer devices from solution, is embedded between the anode and the electroluminescent layer.
Full‐color polymer OLED displays are fabricated by using a novel photolithographic technique (see figure). Electroluminescent polymers with photoresist‐like properties are made by attaching oxetane side groups to the polymers, allowing the structuring of thin films of these materials at high speed and high resolution.
According to the French regulation, stroke units (SU) include both an intensive (I-SU) and a non-intensive (NI-SU) component. Their standard operating procedures have been detailed in governmental ...directives in 2003 and 2007.
To evaluate (i) resources available in French SU, (ii) differences between regions, and between France and the 2 close European countries of similar size, and (iii) to identify avenues for improvement.
We performed a survey of all French SU, with an online questionnaire, to evaluate available resources and activity. We compared the 17 French regions, and France, with Germany and Italy. We used 2019 as year of reference.
The 138 French SU, shared 911 I-SU beds; 123 SU (89.1%) answered the questionnaire. The number of I-SU beds per million inhabitants was 13.6 for the whole country, with important differences between regions, ranging from 7.0 (Reunion Island) to 20.9 (Occitanie region). Per million inhabitants, France had fewer I-SU beds than Germany and Italy (13.5 vs. 29.9 and 23.2 respectively), and fewer thrombectomy centres (0.6 vs. 1.8 and 1.0). Per million inhabitants, France had also lower thrombolysis (203 vs. 402) and thrombectomy (104 vs. 194) rates than Germany, but, compared with Italy, similar thrombolysis rates (203 vs. 202) and higher thrombectomy rates (104 vs. 81).
There are still avenues for improvement in acute stroke care in France, especially concerning the number and regional repartition of I-SU beds, and access to reperfusion therapies.
Objectives: Successful prediction of cardiac complications early in the course of acute ischaemic stroke could have an impact on the clinical management. Markers of myocardial injury on admission ...deserve investigation as potential predictors of poor outcome from stroke. Methods: We prospectively investigated 330 consecutive patients with acute ischaemic stroke admitted to our emergency department based stroke unit. We analysed the association of baseline levels of cardiac troponin I (cTnI) with (a) all-cause mortality over a six month follow up, and (b) inhospital death or major non-fatal cardiac event (angina, myocardial infarction, or heart failure). Results: cTnI levels on admission were normal (lower than 0.10 ng/ml) in 277 patients (83.9%), low positive (0.10–0.39 ng/ml) in 35 (10.6%), and high positive (0.40 ng/ml or higher) in 18 (5.5%). Six month survival decreased significantly across the three groups (p<0.0001, log rank test for trend). On multivariate analysis, cTnI level was an independent predictor of mortality (low positive cTnI, hazard ratio (HR) 2.14; 95% CI 1.13 to 4.05; p = 0.01; and high positive cTnI, HR 2.47; 95% CI 1.22 to 5.02; p = 0.01), together with age and stroke severity. cTnI also predicted a higher risk of the combined endpoint “inhospital death or non-fatal cardiac event”. Neither the adjustment for other potential confounders nor the adjustment for ECG changes and levels of CK-MB and myoglobin on admission altered these results. Conclusions: cTnI positivity on admission is an independent prognostic predictor in acute ischaemic stroke. Whether further evaluation and treatment of cTnI positive patients can reduce cardiac morbidity and mortality should be the focus of future research.
Organic light-emitting diodes (OLEDs) show promise for applications as high-quality self-emissive displays for portable devices such as cellular phones and personal organizers. Although monochrome ...operation is sufficient for some applications, the extension to multi-colour devices-such as RGB (red, green, blue) matrix displays-could greatly enhance their technological impact. Multi-colour OLEDs have been successfully fabricated by vacuum deposition of small electroluminescent molecules, but solution processing of larger molecules (electroluminescent polymers) would result in a cheaper and simpler manufacturing process. However, it has proved difficult to combine the solution processing approach with the high-resolution patterning techniques required to produce a pixelated display. Recent attempts have focused on the modification of standard printing techniques, such as screen printing and ink jetting, but those still have technical drawbacks. Here we report a class of electroluminescent polymers that can be patterned in a way similar to standard photoresist materials-soluble polymers with oxetane sidegroups that can be crosslinked photochemically to produce insoluble polymer networks in desired areas. The resolution of the process is sufficient to fabricate pixelated matrix displays. Consecutive deposition of polymers that are luminescent in each of the three RGB colours yielded a device with efficiencies comparable to state-of-the-art OLEDs and even slightly reduced onset voltages.
Cerebral edema (CED) is a severe complication of acute ischemic stroke. There is uncertainty regarding the predictors for the development of CED after cerebral infarction. We aimed to determine which ...baseline clinical and radiological parameters predict development of CED in patients treated with intravenous thrombolysis.
We used an image-based classification of CED with 3 degrees of severity (less severe CED 1 and most severe CED 3) on postintravenous thrombolysis imaging scans. We extracted data from 42 187 patients recorded in the SITS International Register (Safe Implementation of Treatments in Stroke) during 2002 to 2011. We did univariate comparisons of baseline data between patients with or without CED. We used backward logistic regression to select a set of predictors for each CED severity.
CED was detected in 9579/42 187 patients (22.7%: 12.5% CED 1, 4.9% CED 2, 5.3% CED 3). In patients with CED versus no CED, the baseline National Institutes of Health Stroke Scale score was higher (17 versus 10;
<0.001), signs of acute infarct was more common (27.9% versus 19.2%;
<0.001), hyperdense artery sign was more common (37.6% versus 14.6%;
<0.001), and blood glucose was higher (6.8 versus 6.4 mmol/L;
<0.001). Baseline National Institutes of Health Stroke Scale, hyperdense artery sign, blood glucose, impaired consciousness, and signs of acute infarct on imaging were independent predictors for all edema types.
The most important baseline predictors for early CED are National Institutes of Health Stroke Scale, hyperdense artery sign, higher blood glucose, decreased level of consciousness, and signs of infarct at baseline. The findings can be used to improve selection and monitoring of patients for drug or surgical treatment.
Women are more likely to have a worse outcome after an acute stroke than men. Some studies have suggested that women also benefit less from intravenous thrombolysis after an acute ischemic stroke, ...but others found no sex differences in safety and efficacy. We aimed to evaluate differences in 3-month outcome between sexes in intravenous tissue-type plasminogen activator-treated patients registered in the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register.
A total of 45 079 patients treated with intravenous alteplase were recorded from 2002 to 2011. Main outcome measures were symptomatic intracerebral hemorrhage, functional independence (modified Rankin Scale score, 0-2), and mortality at 3 months.
Among 25 777 (57.2%) men and 19 302 (42.8%) women, we found no difference in the rate of symptomatic intracerebral hemorrhage (P=0.13), a significantly higher likelihood of functional independence at 3 months in men (P<0.0001) and a higher mortality in women when compared with men (P<0.00001). After adjustment for confounding variables, we did not observe any difference between sexes in functional outcome (odds ratio, 1.03; 95% confidence interval, 0.97-1.09; P=0.39), whereas male sex was related to a higher risk of mortality (odds ratio, 1.19; 95% confidence interval, 1.10-1.29; P=0.00003) and symptomatic intracerebral hemorrhage (odds ratio, 1.25, 95% confidence interval, 1.04-1.51; P=0.02).
Data from Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Register suggest that intravenous thrombolysis may modify the observed survival and recovery advantage for men expected in the natural course of an ischemic stroke, with a possible larger beneficial treatment effect in women when compared with men.
The identification of lacunar infarcts before thrombolysis would make it possible either to exclude them from treatment or to show that they also may benefit from it.
To determine whether clinical ...presentation or early CT findings of patients enrolled in the first European Cooperative Acute Stroke Study (ECASS I) trial would identify lacunar infarcts before treatment.
Predictive values, sensitivity, specificity, and accuracy of clinical presentation as pure motor hemiparesis (PMH) or sensorimotor stroke (SMS) syndromes and of baseline CT findings in predicting lacunar infarcts were calculated in the ECASS I patients.
Of 514 patients, 44 placebo (17%) and 44 recombinant tissue plasminogen activator (rt-PA) (18%) patients had PMH/SMS involving at least two of three areas. Thirty-one placebo (12%) and 32 rt-PA (13%) patients had PMH/SMS involving three areas. The 7-day CT was compatible with a lacunar infarct in 32 placebo (12%) and 44 rt-PA (18%) patients. PMH/SMS involving at least two areas had a positive predictive value of 30% both in placebo and rt-PA patients, whereas positive predictive values of the involvement of three areas were 23% and 31%. Those of absence of early CT signs were 21% and 30%, and those of leukoaraiosis or previous lacunar infarcts were 21% and 23%. Positive predictive values of PMH/SMS involving at least two areas combined with absence of early CT signs were 36% in placebo and 33% in t-PA patients, and those of PMH/SMS plus leukoaraiosis or previous lacunes were 28% and 7%, respectively.
In the ECASS I trial, lacunar infarcts were not recognizable on clinical grounds, and early CT findings, alone or in combination with the clinical picture, added poorly to the differential diagnosis.
Atrial fibrillation (AF) is increasingly recognized as the single most important cause of disabling ischemic stroke in the elderly. We undertook an international survey to characterize the frequency ...of AF-associated stroke, methods of AF detection, and patient features.
Consecutive patients hospitalized for ischemic stroke in 2013 to 2014 were surveyed from 19 stroke research centers in 19 different countries. Data were analyzed by global regions and World Bank income levels.
Of 2144 patients with ischemic stroke, 590 (28%; 95% confidence interval, 25.6-29.5) had AF-associated stroke, with highest frequencies in North America (35%) and Europe (33%) and lowest in Latin America (17%). Most had a history of AF before stroke (15%) or newly detected AF on electrocardiography (10%); only 2% of patients with ischemic stroke had unsuspected AF detected by poststroke cardiac rhythm monitoring. The mean age and 30-day mortality rate of patients with AF-associated stroke (75 years; SD, 11.5 years; 10%; 95% confidence interval, 7.6-12.6, respectively) were substantially higher than those of patients without AF (64 years; SD, 15.58 years; 4%; 95% confidence interval, 3.3-5.4; P<0.001 for both comparisons). There was a strong positive correlation between the mean age and the frequency of AF (r=0.76; P=0.0002).
This cross-sectional global sample of patients with recent ischemic stroke shows a substantial frequency of AF-associated stroke throughout the world in proportion to the mean age of the stroke population. Most AF is identified by history or electrocardiography; the yield of conventional short-duration cardiac rhythm monitoring is relatively low. Patients with AF-associated stroke were typically elderly (>75 years old) and more often women.
Background
Recent evidence supports that most non-lacunar cryptogenic strokes are embolic. Accordingly, these strokes have been designated as embolic strokes of undetermined source (ESUS).
Aims
We ...undertook an international survey to characterize the frequency and clinical features of ESUS patients across global regions.
Methods
Consecutive patients hospitalized for ischemic stroke were retrospectively surveyed from 19 stroke research centers in 19 different countries to collect patients meeting criteria for ESUS.
Results
Of 2144 patients with recent ischemic stroke, 351 (16%, 95% CI 15% to 18%) met ESUS criteria, similar across global regions (range 16% to 21%), and an additional 308 (14%) patients had incomplete evaluation required for ESUS diagnosis. The mean age of ESUS patients (62 years; SD = 15) was significantly lower than the 1793 non-ESUS ischemic stroke patients (68 years, p ≤ 0.001). Excluding patients with atrial fibrillation (n = 590, mean age = 75 years), the mean age of the remaining 1203 non-ESUS ischemic stroke patients was 64 years (p = 0.02 vs. ESUS patients). Among ESUS patients, hypertension, diabetes, and prior stroke were present in 64%, 25%, and 17%, respectively. Median NIHSS score was 4 (interquartile range 2–8). At discharge, 90% of ESUS patients received antiplatelet therapy and 7% received anticoagulation.
Conclusions
This cross-sectional global sample of patients with recent ischemic stroke shows that one-sixth met criteria for ESUS, with additional ESUS patients likely among those with incomplete diagnostic investigation. ESUS patients were relatively young with mild strokes. Antiplatelet therapy was the standard antithrombotic therapy for secondary stroke prevention in all global regions.
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