Recent successful industrial applications of ultra dispersed diamond have triggered additional scientific interest in its structure and surface properties, as well as changes in these properties upon ...various post-treatments. In this work, we report a systematic study of the structure of nanocrystalline diamond powder before and after sintering by using multi-wavelength Raman spectroscopy, high resolution transmission electron microscopy, and sorption measurements. Purified nanodiamond powder showed the presence of amorphous carbon and carbon onions and had a specific surface area of about 200 m
2/g. Sintering performed for 3 min at 4.5–7 GPa of quasi-hydrostatic pressure at 1400 °C resulted in the decrease of sp
2 carbon content in the diamond sample, an increase in the average size of diamond grains, and noticeable broadening of the grain size distribution. Sintered nanodiamond retained a porous structure and demonstrated a specific surface area of about 135 m
2/g. The produced material can be used as a fine abrasive powder, as a stationary phase in chromatography or as a durable bio-compatible membrane (filter) for bio-medical applications. This work demonstrated the successful sintering of nanodiamond and could be used for optimizing the production process of the porous nanocrystalline diamond with desired characteristics.
. Burkard T, Kaiser CA, Brunner‐La Rocca H, Osswald S, Pfisterer ME, Jeger RV for the BASKET Investigators (Cardiology, University Hospital; and Cardiology, Maastricht University Hospital Center, ...Maastricht, the Netherlands). Combined clopidogrel and proton pump inhibitor therapy is associated with higher cardiovascular event rates after percutaneous coronary intervention: a report from the BASKET trial. J Intern Med 2012; 271: 257–263.
Objective. To investigate whether there is an increased risk of cardiac events with a combined therapy of clopidogrel and proton pump inhibitors (PPIs) after percutaneous coronary intervention (PCI).
Design. In the BAsel Stent Kosten Effektivitäts Trial (BASKET), all patients undergoing PCI received 6 months of clopidogrel and were analysed for the use of PPI therapy. Endpoints were major adverse cardiac events (MACE), myocardial infarction (MI), death and target vessel revascularization (TVR) after 36 months.
Results. Of 801 patients with available discharge medication data, 109 (14%) received PPIs. Patients who received PPIs were older (66.5 ± 10.5 vs. 63.3 ± 11.3 years, P = 0.006), more likely to be woman (80% vs. 69%, P = 0.009) and have a history of diabetes (29.6% vs. 17.3%, P = 0.002) or gastrointestinal ulcer disease (8.3% vs. 3.3%, P = 0.015) and more often received nonsteroidal anti‐inflammatory drugs (7.3% vs. 2.2%, P = 0.003) and corticosteroids (11% vs. 3.6%, P = 0.001) but not aspirin (91.7% vs. 97%, P = 0.008) compared with those who did not receive PPIs. Patients who received PPI therapy had higher rates of MACE (30.3% vs. 20.8%, P = 0.027) and MI (14.7% vs. 7.4%, P = 0.01) but similar rates of death (9.2% vs. 7.4%, P = 0.51) and TVR (20.2% vs. 15.3%, P = 0.2) compared with those who did not. By multivariate analysis, diabetes (hazard ratio 1.83, 95% confidence interval 1.07–3.15) and PPI use (hazard ratio 1.88, 95% confidence interval 1.05–3.37) were the only independent risk factors for MI.
Conclusion. In a real‐world PCI population, the combination of PPIs and clopidogrel was associated with a doubling of MI rates after 3 years. Even after correction for confounding factors, concomitant PPI use remained an independent predictor of outcome emphasizing the clinical importance of this drug–drug interaction.
Abstract Background Diabetes is a major risk factor for acute myocardial infarction (AMI). Assessment of diabetic patients is challenging due to an often atypical presentation of symptoms. We aimed ...to evaluate the two novel biomarkers copeptin and high-sensitive cardiac troponin (hs-TnT) for the improvement of early diagnosis and risk-stratification in patients with diabetes and suspected AMI. Methods In this prospective international multicenter study we evaluated 379 patients with diabetes in a cohort of 1991 patients presenting with symptoms suggestive of AMI. The measurement of biomarkers was performed at presentation. Results Among the 379 diabetic patients, 32.7% had AMI, and in the 1621 patients without diabetes, 18.8% had AMI. The additional use of copeptin improved the diagnostic accuracy provided by conventional troponin alone (AUC 0.86 vs. 0.79, p = 0.004). During a median follow-up of 814 days, 49 (13.1%) diabetic patients died. Cumulative 2-year survival rate for patients with copeptin levels below 9 pmol/l was 96.6% compared to 82.8% in patients above that level (p < 0.001). The same was observed for hs-TnT with a cutoff level of 14 ng/l (97.7% vs. 82.0%, p < 0.001) respective of cTnT with a cutoff level of 10 ng/l (93.5% vs. 75.6%, p < 0.001). In multivariate Cox analysis, copeptin, hs-TnT and cTnT were strong and independent predictors of 24-month-mortality. Using the dual marker strategy (copeptin and troponin) identified two groups of high-risk patients where 22.5% of the group with hs-cTnT and copeptin above the cutoff and 28.6% with cTnT and copeptin above the cutoff died. Conclusion In diabetic patients, copeptin only slightly improves the early diagnosis of AMI provided by hs-cTnT. However, both markers (copeptin and troponin) predict long-term mortality accurately and independently of each other.
Spreading Vesicles in a Neonate Glade, Daniel C.; Sitabkhan, Amreen Z.; Osswald, Sandra S.
The Journal of pediatrics,
April 2020, 2020-Apr, 2020-04-00, 20200401, Letnik:
219
Journal Article
Background and purpose: In some Western countries, many stroke patients undergo routine tests including ECG, echocardiography, carotid ultrasound and Holter monitoring, even though they have been ...shown to express limited value in unselected patients. Comprehensive data on yield of tests, especially on consequences taken from positive test results, are scanty.
Methods: Consecutive stroke patients with evidence of ischaemic lesions by imaging techniques were included. Aetiology was determined using TOAST‐classifications. Rates of positive test results and their impact on drug therapy, especially anticoagulation were evaluated.
Results: Two hundred and forty‐one consecutive patients, age 69 ± 13 years were included. Positive test results were documented in 19% with 12‐lead ECG, 24% with carotid ultrasound, 24% with echocardiography and never with Holter monitoring. Overall, in 41% positive test results were present. Apart from echocardiography (37%), a change of therapy resulted in 51–56% of patients with a positive test result.
Conclusions: Even though 12‐lead ECG, carotid ultrasound and echocardiography only had relatively low incidences of positive findings, their impact on management in case of positive test results was quite high. Nevertheless, future studies to select patients more appropriately are needed. In contrast, Holter monitoring had no impact and should not be used in routine evaluation of stroke patients.
Background: Implantable cardioverter defibrillators (ICD's) are increasingly used for primary and secondary prevention of sudden cardiac death. However, data on how many ICD patients indeed receive ...appropriate ICD therapy during long-term follow-up is scarce.
Aim: The aim of our study was to determine the number of patients without appropriate ICD therapy 5 years after ICD implantation, to identify predicting factors, to assess the occurrence of late first ICD therapy and to quantify the financial impact of ICD therapy in a real-world setting.
Design: Prospective observational study.
Methods: We prospectively enrolled 322 consecutive ICD patients. Baseline data were collected at implantation and patients were followed for a median of 7.3 years (IQR 5.8-9.2 years). Time to first appropriate ICD therapy (either antitachycardia pacing or cardioversion) was documented.
Results: Five years after implantation, 139 patients (43%) had not received appropriate ICD therapy. In multivariable analysis, a primary prevention indication and negative electrophysiological studies prior to ICD implantation were independent predictors of freedom from ICD therapy. Of the patients without ICD therapy, 5 years after implantation, 25% had experienced inappropriate ICD shocks. Two hundred and seven devices (1.5 devices per patient) were needed for the 139 patients without ICD intervention within 5 years, accounting for €31 784 per patient. During an additional follow-up of 3 years, 12% of the patients with unused ICD received a late first appropriate ICD therapy.
Conclusions: About half of the ICD patients receive appropriate ICD therapy within 5 years after implantation. Furthermore, there is a significant proportion of patients receiving late first shocks after five initially uneventful years.
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