10 research outputs found
Stimulated emission depletion microscopy with a single depletion laser using five fluorochromes and fluorescence lifetime phasor separation
Stimulated emission depletion (STED) microscopy achieves super-resolution by exciting a diffraction-limited volume and then suppressing fluorescence in its outer parts by depletion. Multiple depletion lasers may introduce misalignment and bleaching. Hence, a single depletion wavelength is preferable for multi-color analyses. However, this limits the number of usable spectral channels. Using cultured cells, common staining protocols, and commercially available fluorochromes and microscopes we exploit that the number of fluorochromes in STED or confocal microscopy can be increased by phasor based fluorescence lifetime separation of two dyes with similar emission spectra but different fluorescent lifetimes. In our multi-color FLIM-STED approach two fluorochromes in the near red (exc. 594 nm, em. 600–630) and two in the far red channel (633/641–680), supplemented by a single further redshifted fluorochrome (670/701–750) were all depleted with a single laser at 775 nm thus avoiding potential alignment issues. Generally, this approach doubles the number of fully distinguishable colors in laser scanning microscopy. We provide evidence that eight color FLIM-STED with a single depletion laser would be possible if suitable fluorochromes were identified and we confirm that a fluorochrome may have different lifetimes depending on the molecules to which it is coupled
Instruments of official communication by regulatory authorities on risks of drug use
Active communication of authorities, such as the Federal Institute for Drugs and Medical Devices (BfArM) and the Paul Ehrlich Institute (PEI), including maintenance of contacts with health care professionals, as well as press and public relations work, are essential prerequisites for ensuring that information on the risks of using medicinal products reaches both affected patients and healthcare professionals quickly and in a targeted manner. The various instruments of targeted communication describe possible risks and also contain recommendations that help to reduce the risk of using a medicinal product. The supplementary public relations work aims to make the tasks and objectives of the authority known to the public and to experts with the goal of creating and expanding trust in the actions of the authorities. To this end, appropriate communication platforms must be established and accepted so that they are used by both experts and the general public and the authority is perceived and appreciated as a reliable source of risk information. The currently available instruments of targeted risk communication, such as Dear Health Care Professional Communication (DHPC), risk management plans, and educational materials are described in this paper as well as broader communication on official websites or towards the media. Finally, PEI’s risk communication is highlighted with particular reference to COVID-19 vaccines.Die aktive Kommunikation von Behörden, wie dem Bundesinstitut für Arzneimittel und Medizinprodukte (BfArM) und dem Paul-Ehrlich-Institut (PEI), einschließlich der Kontaktpflege zu Fachkreisen sowie Presse- und Öffentlichkeitsarbeit sind wesentliche Voraussetzung dafür, dass Informationen zu Anwendungsrisiken von Arzneimitteln sowohl betroffene Patientinnen und Patienten als auch Angehörige der Heilberufe schnell und gezielt erreichen. Die verschiedenen Instrumente der gezielten Kommunikation beschreiben mögliche Risiken und enthalten darüber hinaus auch Empfehlungen, die helfen, das Anwendungsrisiko eines Arzneimittels zu reduzieren. Die ergänzende Öffentlichkeitsarbeit zielt darauf ab, die Aufgaben und Ziele der Behörde in der Bevölkerung und in Fachkreisen bekannt zu machen, um Vertrauen in behördliches Handeln zu schaffen und auszubauen. Dafür müssen entsprechende Kommunikationsplattformen etabliert und akzeptiert sein, die sowohl von Fachkreisen als auch von der Bevölkerung genutzt werden können. Die aktuell verfügbaren Instrumente der gezielten Risikokommunikation, wie Rote-Hand-Briefe (RHB), Risikomanagementpläne und Schulungsmaterial, werden in dieser Publikation ebenso beschrieben wie die breiter angelegte Kommunikation auf den behördlichen Webseiten oder gegenüber den Medien. Schließlich wird die Risikokommunikation des PEI unter besonderer Berücksichtigung der COVID-19-Impfstoffe beleuchtet
Incremental value of heart-type fatty acid-binding protein in suspected acute myocardial infarction early after symptom onset.
BACKGROUND
The early diagnosis of acute myocardial infarction (AMI) very soon after symptom onset remains a major clinical challenge, even when using high-sensitivity cardiac troponin (hs-cTnT).
METHODS AND RESULTS
We investigated the incremental value of heart-type fatty acid-binding protein (hFABP) in a pre-specified subgroup analysis of patients presenting with suspected AMI within 1 h of symptom onset to the emergency department (ED) in a multicentre study. HFABP was measured in a blinded fashion. Two independent cardiologists using all available clinical information, including hs-cTnT, adjudicated the final diagnosis. Overall, 1411 patients were enrolled, of whom 105 patients presented within 1 h of symptom onset. Of these, 34 patients (32.4%) had AMI. The diagnostic accuracy as quantified by the area under the receiver-operating characteristics curve (AUC) of hFABP was high (0.84 (95% CI 0.74-0.94)). However, the additional use of hFABP only marginally increased the diagnostic accuracy of hs-cTnT (AUC 0.88 (95% CI 0.81-0.94) for hs-cTnT alone to 0.90 (95% CI 0.83-0.98) for the combination; p=ns). After the exclusion of 18 AMI patients with ST-segment elevation, similar results were obtained. Among the 16 AMI patients without ST-segment elevation, six had normal hs-cTnT at presentation. Of these, hFABP was elevated in two (33.3%) patients.
CONCLUSIONS
hFABP does not seem to significantly improve the early diagnostic accuracy of hs-cTnT in the important subgroup of patients with suspected AMI presenting to the ED very early after symptom onset
Incremental value of copeptin in suspected acute myocardial infarction very early after symptom onset.
BACKGROUND
Patients presenting very early after chest pain onset may provide a diagnostic challenge even when using a high-sensitivity cardiac troponin (hs-cTnT). We hypothesized that in these patients the incremental value of copeptin in the early diagnosis of acute myocardial infarction (AMI) may be substantial.
METHODS
We aimed to investigate the incremental value of copeptin in a pre-specified subgroup analysis of patients presenting with suspected AMI to the emergency department within 2 hours of symptom onset in a multicenter study. Copeptin was measured in a blinded fashion. Two independent cardiologists adjudicated the final diagnosis using all available clinical informations, including high-sensitivity cardiac troponin T (hs-cTnT).
RESULTS
Overall, 2000 patients were enrolled, of whom 519 (26%) arrived within 2 hours of symptom onset. Of these, 102 patients (20%) had an AMI. The additional use of copeptin did not increase diagnostic accuracy as quantified by the area under the receiver-operating characteristic curve (AUC) of hs-cTnT (0.87 (95% confidence interval (CI): 0.83-0.90) for hs-cTnT alone to 0.86 (95% CI: 0.82-0.90) for the combination; p = NS). Copeptin (using 9 pmol/L as a cut-off) increased the negative predictive value (NPV) of hs-cTnT (using 14 ng/L as a cut-off) alone from 93% (95% CI: 90-95%) to 96% (95% CI: 93-98%). The NPV for the combination of hs-cTnT and copeptin was lower in patients arriving in the first 2 hours than in those arriving after 2 hours: 96% (95% CI: 93-98%) versus 99% (95% CI: 99-100%), respectively.
CONCLUSIONS
The additional use of copeptin on top of hs-cTnT seems to lead to a small increase in NPV, but no increase in AUC. Routine use of copeptin in early presenters does not seem warranted
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Efficacy and Biomarker Study of Bevacizumab for Hearing Loss Resulting From Neurofibromatosis Type 2–Associated Vestibular Schwannomas
Purpose
Neurofibromatosis type 2 (NF2) is a tumor predisposition syndrome characterized by bilateral vestibular schwannomas (VSs) resulting in deafness and brainstem compression. This study evaluated efficacy and biomarkers of bevacizumab activity for NF2-associated progressive and symptomatic VSs.
Patients and Methods
Bevacizumab 7.5 mg/kg was administered every 3 weeks for 46 weeks, followed by 24 weeks of surveillance after treatment with the drug. The primary end point was hearing response defined by word recognition score (WRS). Secondary end points included toxicity, tolerability, imaging response using volumetric magnetic resonance imaging analysis, durability of response, and imaging and blood biomarkers.
Results
Fourteen patients (estimated to yield > 90% power to detect an alternative response rate of 50% at alpha level of 0.05) with NF2, with a median age of 30 years (range, 14 to 79 years) and progressive hearing loss in the target ear (median baseline WRS, 60%; range 13% to 82%), were enrolled. The primary end point, confirmed hearing response (improvement maintained ≥ 3 months), occurred in five (36%) of 14 patients (95% CI, 13% to 65%; P < .001). Eight (57%) of 14 patients had transient hearing improvement above the 95% CI for WRS. No patients experienced hearing decline. Radiographic response was seen in six (43%) of 14 target VSs. Three grade 3 adverse events, hypertension (n = 2) and immune-mediated thrombocytopenic purpura (n = 1), were possibly related to bevacizumab. Bevacizumab treatment was associated with decreased free vascular endothelial growth factor (not bound to bevacizumab) and increased placental growth factor in plasma. Hearing responses were inversely associated with baseline plasma hepatocyte growth factor (P = .019). Imaging responses were associated with high baseline tumor vessel permeability and elevated blood levels of vascular endothelial growth factor D and stromal cell–derived factor 1α (P = .037 and .025, respectively).
Conclusion
Bevacizumab treatment resulted in durable hearing response in 36% of patients with NF2 and confirmed progressive VS-associated hearing loss. Imaging and plasma biomarkers showed promising associations with response that should be validated in larger studies
Empagliflozin in Patients with Chronic Kidney Disease
Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo