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1.
Appl Opt ; 60(28): 8890-8895, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613115

RESUMO

This paper presents the bidirectional confocal measurement of a microsphere, which enables the simple measurement of the sphere with a similar number of measuring points taken on its upper and its lower hemispheres. The innovative measuring strategy is the placement of the sphere above a mirror and the subsequent measurement of the upper hemisphere on the real sphere and the lower hemisphere on the mirrored sphere. While theoretical explanations are given first, the main focus of the paper is the presentation of the idea itself and the very promising empirical findings. We believe these findings prove that the measuring strategy presented has the potential to become a prime method for the optical characterization of microspheres.

2.
Eur Heart J Acute Cardiovasc Care ; 10(7): 746-755, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33620434

RESUMO

AIMS: Diagnosis of acute myocardial infarction (AMI) can be challenging in patients with prior coronary artery bypass grafting (CABG). METHODS AND RESULTS: Final diagnoses were adjudicated by two independent cardiologists using the universal definition of AMI among patients presenting to the emergency department (ED) with suspected AMI. Diagnostic accuracy of 34 chest pain characteristics (CPCs) and four electrocardiogram (ECG) signatures stratified according to the presence or absence of prior CABG were prospectively quantified. Among 4015 patients (no prior CABG: n = 3686; prior CABG: n = 329), prevalence of AMI and unstable angina were higher in patients with prior CABG (35% vs. 18%; 26% vs. 8%; both P < 0.001). Three CPCs (9%) and two electrocardiographic findings (50%) showed a different diagnostic performance (interaction P < 0.05) with loss of diagnostic value in patients with prior CABG. The diagnostic accuracy as quantified by the area under the curve (AUC) of the integrated clinical judgement was moderate to good in patients with prior CABG, and significantly lower compared to patients without prior CABG [AUC 0.80 (95% confidence interval (CI) 0.75-0.84) vs. AUC 0.87 (95% CI 0.86-0.89); P = 0.004]. Time to discharge from the ED was significantly longer in patients with prior CABG [359 (215-525) min vs. 300 (192-435) min; P < 0.001]. Key findings were confirmed in a large independent external validation cohort (n = 13 653). CONCLUSIONS: Patients with prior CABG presenting with suspected AMI have a high prevalence of AMI and unstable angina and lower diagnostic accuracy of CPCs and the ECG, possibly justifying liberal use of early coronary angiography in these vulnerable patients. CLINICALTRIALS.GOV REGISTRY: Number NCT00470587.


Assuntos
Ponte de Artéria Coronária , Infarto do Miocárdio , Angina Instável , Dor no Peito , Eletrocardiografia , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia
3.
Aliment Pharmacol Ther ; 52(5): 855-865, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32683724

RESUMO

BACKGROUND: In patients with cirrhosis, progression to acute decompensation (AD) and acute-on-chronic liver failure (ACLF) has been associated with poor prognosis. Differential leucocyte ratios might predict mortality in systemic inflammatory conditions. AIM: To evaluate differential leucocyte ratios as prognostic biomarkers in patients with cirrhosis. METHODS: Patients with AD and ACLF were recruited from four centres in three countries. Peripheral blood differential leucocytes were measured (three centres using flow cytometry) on hospital admission and at 48 hours. Ratios were correlated to model for end-stage liver disease (MELD), chronic liver failure-sequential organ failure (CLIF-SOFA), suspected/culture-positive bacterial infection and survival. RESULTS: Nine hundred twenty-six patients (562 (61%) male, median age 55 (25-94) years) were studied. Overall, 350 (37%) did not survive to hospital discharge. Neutrophil-lymphocyte ratio (NLR) and monocyte-lymphocyte ratio (MLR) were elevated in patients with AD and ACLF who died during their hospital stay. On multivariate analysis NLR retained statistical significance independently of CLIF-SOFA or MELD. NLR >30 was associated with an 80% 90-day mortality in patients with ACLF but not AD. On sensitivity analysis for subgroups (alcohol-related liver disease and suspected sepsis), NLR and MLR retained statistically robust accuracy for the prediction of mortality. Significant predictive accuracy was only observed in centres using flow cytometry. CONCLUSION: Leucocyte ratios are simple and robust biomarkers of outcome in ACLF, which are comparable to CLIF-SOFA score but dependent on leucocyte quantification method. NLR and MLR may be used as screening tools for mortality prediction in patients with acutely deteriorating cirrhosis.


Assuntos
Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/mortalidade , Biomarcadores/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/mortalidade , Linfócitos/patologia , Insuficiência Hepática Crônica Agudizada/sangue , Insuficiência Hepática Crônica Agudizada/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Doença Hepática Terminal/sangue , Doença Hepática Terminal/diagnóstico , Doença Hepática Terminal/mortalidade , Doença Hepática Terminal/terapia , Feminino , Mortalidade Hospitalar , Humanos , Contagem de Leucócitos , Cirrose Hepática/sangue , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Escores de Disfunção Orgânica , Prognóstico , Análise de Sobrevida
4.
J Am Coll Cardiol ; 74(7): 842-854, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31416527

RESUMO

BACKGROUND: Early and accurate detection of short-term major adverse cardiac events (MACE) in patients with suspected acute myocardial infarction (AMI) is an unmet clinical need. OBJECTIVES: The goal of this study was to test the hypothesis that adding clinical judgment and electrocardiogram findings to the European Society of Cardiology (ESC) high-sensitivity cardiac troponin (hs-cTn) measurement at presentation and after 1 h (ESC hs-cTn 0/1 h algorithm) would further improve its performance to predict MACE. METHODS: Patients presenting to an emergency department with suspected AMI were enrolled in a prospective, multicenter diagnostic study. The primary endpoint was MACE, including all-cause death, cardiac arrest, AMI, cardiogenic shock, sustained ventricular arrhythmia, and high-grade atrioventricular block within 30 days including index events. The secondary endpoint was MACE + unstable angina (UA) receiving early (≤24 h) revascularization. RESULTS: Among 3,123 patients, the ESC hs-cTnT 0/1 h algorithm triaged significantly more patients toward rule-out compared with the extended algorithm (60%; 95% CI: 59% to 62% vs. 45%; 95% CI: 43% to 46%; p < 0.001), while maintaining similar 30-day MACE rates (0.6%; 95% CI: 0.3% to 1.1% vs. 0.4%; 95% CI: 0.1% to 0.9%; p = 0.429), resulting in a similar negative predictive value (99.4%; 95% CI: 98.9% to 99.6% vs. 99.6%; 95% CI: 99.2% to 99.8%; p = 0.097). The ESC hs-cTnT 0/1 h algorithm ruled-in fewer patients (16%; 95% CI: 14.9% to 17.5% vs. 26%; 95% CI: 24.2% to 27.2%; p < 0.001) compared with the extended algorithm, albeit with a higher positive predictive value (76.6%; 95% CI: 72.8% to 80.1% vs. 59%; 95% CI: 55.5% to 62.3%; p < 0.001). For 30-day MACE + UA, the ESC hs-cTnT 0/1 h algorithm had a higher positive predictive value for rule-in, whereas the extended algorithm had a higher negative predictive value for the rule-out. Similar findings emerged when using hs-cTnI. CONCLUSIONS: The ESC hs-cTn 0/1 h algorithm better balanced efficacy and safety in the prediction of MACE, whereas the extended algorithm is the preferred option for the rule-out of 30-day MACE + UA. (Advantageous Predictors of Acute Coronary Syndromes Evaluation [APACE]; NCT00470587).


Assuntos
Algoritmos , Infarto do Miocárdio/epidemiologia , Troponina/sangue , Idoso , Angina Instável/diagnóstico , Angina Instável/epidemiologia , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/epidemiologia , Bloqueio Atrioventricular/diagnóstico , Bloqueio Atrioventricular/epidemiologia , Biomarcadores/sangue , Eletrocardiografia , Serviço Hospitalar de Emergência , Feminino , Parada Cardíaca/diagnóstico , Parada Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/diagnóstico , Revascularização Miocárdica , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/epidemiologia
5.
J Am Coll Cardiol ; 74(4): 483-494, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31345421

RESUMO

BACKGROUND: The European Society of Cardiology (ESC) recommends the 0/1-h algorithm for rapid triage of patients with suspected non-ST-segment elevation myocardial infarction (MI). However, its impact on patient management and safety when routinely applied is unknown. OBJECTIVES: This study sought to determine these important real-world outcome data. METHODS: In a prospective international study enrolling patients presenting with acute chest discomfort to the emergency department (ED), the authors assessed the real-world performance of the ESC 0/1-h algorithm using high-sensitivity cardiac troponin T embedded in routine clinical care and its associated 30-day rates of major adverse cardiac events (MACE) (the composite of cardiovascular death and MI). RESULTS: Among 2,296 patients, non-ST-segment elevation MI prevalence was 9.8%. In median, 1-h blood samples were collected 65 min after the 0-h blood draw. Overall, 94% of patients were managed without protocol violations, and 98% of patients triaged toward rule-out did not require additional cardiac investigations including high-sensitivity cardiac troponin T measurements at later time points or coronary computed tomography angiography in the ED. Median ED stay was 2 h and 30 min. The ESC 0/1-h algorithm triaged 62% of patients toward rule-out, and 71% of all patients underwent outpatient management. Proportion of patients with 30-day MACE were 0.2% (95% confidence interval: 03% to 0.5%) in the rule-out group and 0.1% (95% confidence interval: 0% to 0.2%) in outpatients. Very low MACE rates were confirmed in multiple subgroups, including early presenters. CONCLUSIONS: These real-world data document the excellent applicability, short time to ED discharge, and low rate of 30-day MACE associated with the routine clinical use of the ESC 0/1-h algorithm for the management of patients presenting with acute chest discomfort to the ED.


Assuntos
Algoritmos , Fidelidade a Diretrizes , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Fatores de Tempo , Triagem/normas
6.
Beilstein J Nanotechnol ; 8: 1145-1155, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28685115

RESUMO

A facile method to coat carbon fibers with a silica shell is presented in this work. By immobilizing linear polyamines on the carbon fiber surface, the high catalytic activity of polyamines in the sol-gel-processing of silica precursors is used to deposit a silica coating directly on the fiber's surface. The surface localization of the catalyst is achieved either by attaching short-chain polyamines (e.g., tetraethylenepentamine) via covalent bonds to the carbon fiber surface or by depositing long-chain polyamines (e.g., linear poly(ethylenimine)) on the carbon fiber by weak non-covalent bonding. The long-chain polyamine self-assembles onto the carbon fiber substrate in the form of nanoscopic crystallites, which serve as a template for the subsequent silica deposition. The silicification at close to neutral pH is spatially restricted to the localized polyamine and consequently to the fiber surface. In case of the linear poly(ethylenimine), silica shells of several micrometers in thickness can be obtained and their morphology is easily controlled by a considerable number of synthesis parameters. A unique feature is the hierarchical biomimetic structure of the silica coating which surrounds the embedded carbon fiber by fibrillar and interconnected silica fine-structures. The high surface area of the nanostructured composite fiber may be exploited for catalytic applications and adsorption purposes.

7.
Dalton Trans ; 42(30): 10786-97, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-23775495

RESUMO

The novel homochiral metal-organic framework CFA-1 (Coordination Framework Augsburg-1), [Zn5(OAc)4(bibta)3], containing the achiral linker {H2-bibta = 1H,1'H-5,5'-bibenzo[d][1,2,3]triazole}, has been synthesised. The reaction of H2-bibta and Zn(OAc)2·2H2O in N-methylformamide (NMF) (90 °C, 3 d) yields CFA-1 as trigonal prismatic single crystals. CFA-1 serves as a convenient precursor for the synthesis of isostructural frameworks with redox-active metal centres, which is demonstrated by the postsynthetic exchange of Zn(2+) by Co(2+) ions. The framework is robust to solvent removal and has been structurally characterized by synchrotron single-crystal X-ray diffraction and solid state NMR measurements ((13)C MAS- and (1)H MAS-NMR at 10 kHz). Results from MAS-NMR and IR spectroscopy studies are corroborated by cluster and periodic DFT calculations performed on CFA-1 cluster fragments.

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