State of the art of BNP and NT-proBNP immunoassays: The CardioOrmoCheck study

To evaluate differences in analytical performance and clinical results of BNP and NT-proBNP immunoassays, a proficiency testing program, called CardioOrmoCheck study, has been organized since 2005 under the patronage of the Study Group of the Cardiovascular Biomarkers of the Italian Society of Clinical Biochemistry (SIBIOC). On average more than 100 Italian laboratories were involved in the annual 2005–2011 cycles. In total, 72 study samples were distributed and measured by participant laboratories for a total of 6706 results. A great difference in between-method variability was found between BNP (43.0 CV%) and NT-proBNP (8.7 CV%) immunoassays. However, with the only exception of the POCT method for BNP assay, all immunoassay methods showed an imprecision≤10 CV% at the cut-off levels (i.e. 100 ng/L for BNP and 400 ng/L for NT-proBNP assay, respectively). Furthermore, CardioOrmoCheck study demonstrated that the most popular BNP immunoassays are affected by large systematic differences (on average more than 2 folds between TRIAGE Beckman-Coulter and ADVIA Centaur Siemens methods), while the agreement between NT-proBNP methods was better. CardioOrmoCheck study demonstrates that there are marked differences in analytical performance and measured values in particular among commercialmethods for BNP assay. These findings suggest that it may be not reasonable to recommend identical cut-off or decision values for all BNP immunoassays

Evaluation of analytical performance and comparison of clinical results of the new generation method AccuTnI+3 for the measurement of cardiac troponin I using both patients and quality control plasma samples

The study aims are to evaluate the analytical performance and the clinical results of the chemiluminescent Access AccuTnI+3 immunoassay for the determination of cardiac troponin I (cTnI)with DxI 800 and Access2 platforms and to compare the clinical results obtained with this method with those of three cTnI immunoassays, recently introduced in the European market. The limits of blank (LoB), detection (LoD), and quantitation (LoQ) at 20% CV and 10% CV were 4.5 ng/L and 10.9 ng/L, 17.1 and 30.4 ng/L, respectively. The results of STAT Architect high Sensitive TnI (Abbott Diagnostics), ADVIA Centaur Troponin I Ultra (Siemens Healthcare Diagnostics), ST AIA-Pack cTnI third generation (Tosoh Bioscience), and Access AccuTnI + 3 (Beckman Coulter Diagnostics) showed very close correlations (R ranging from 0.901 to 0.994) in 122 samples of patients admitted to the emergency department. However, on average there was a difference up to 2.4-fold between the method measuring the highest (ADVIA method) and lowest cTnI values (AccuTnI + 3 method). The consensus mean values between methods ranged from 6.2% to 29.6% in 18 quality control samples distributed in an external quality control study (cTnI concentrations ranging from 29.3 ng/L to 1557.5 ng/L). In conclusion, the results of our analytical evaluation concerning the AccuTnI + 3 method, using the DxI platform, are well in agreement with those suggested by the manufacturer as well as those reported by some recent studies using the Access2 platform. Our results confirm that the AccuTnI + 3 method for the Access2 and DxI 800 platforms is a clinically usable method for cTnI measurement

Biodegradable nanomats produced by electrospinning : expanding multifunctionality and potential for tissue engineering

With increasing interest in nanotechnology, development of nanofibers (n-fibers) by using the technique of electrospinning is gaining new momentum. Among important potential applications of n-fiber-based structures, scaffolds for tissue-engineering represent an advancing front. Nanoscaffolds (n-scaffolds) are closer to natural extracellular matrix (ECM) and its nanoscale fibrous structure. Although the technique of electrospinning is relatively old, various improvements have been made in the last decades to explore the spinning of submicron fibers from biodegradable polymers and to develop also multifunctional drug-releasing and bioactive scaffolds. Various factors can affect the properties of resulting nanostructures that can be classified into three main categories, namely: (1) Substrate related, (2) Apparatus related, and (3) Environment related factors. Developed n-scaffolds were tested for their cytocompatibility using different cell models and were seeded with cells for to develop tissue engineering constructs. Most importantly, studies have looked at the potential of using n-scaffolds for the development of blood vessels. There is a large area ahead for further applications and development of the field. For instance, multifunctional scaffolds that can be used as controlled delivery system do have a potential and have yet to be investigated for engineering of various tissues. So far, in vivo data on n-scaffolds are scarce, but in future reports are expected to emerge. With the convergence of the fields of nanotechnology, drug release and tissue engineering, new solutions could be found for the current limitations of tissue engineering scaffolds, which may enhance their functionality upon in vivo implantation. In this paper electrospinning process, factors affecting it, used polymers, developed n-scaffolds and their characterization are reviewed with focus on application in tissue engineering

State of the art of BNP and NT-proBNP immunoassays: The CardioOrmoCheck study.

To evaluate differences in analytical performance and clinical results of BNP and NT-proBNP immunoassays, a proficiency testing program, called CardioOrmoCheck study, has been organized since 2005 under the patronage of the Study Group of the Cardiovascular Biomarkers of the Italian Society of Clinical Biochemistry (SIBIOC). On average more than 100 Italian laboratories were involved in the annual 2005–2011 cycles. In total, 72 study samples were distributed and measured by participant laboratories for a total of 6706 results. A great difference in between-method variability was found between BNP (43.0 CV%) and NT-proBNP (8.7 CV%) immunoassays. However, with the only exception of the POCT method for BNP assay, all immunoassay methods showed an imprecision≤10 CV% at the cut-off levels (i.e. 100 ng/L for BNP and 400 ng/L for NT-proBNP assay, respectively). Furthermore, CardioOrmoCheck study demonstrated that the most popular BNP immunoassays are affected by large systematic differences (on average more than 2 folds between TRIAGE Beckman-Coulter and ADVIA Centaur Siemens methods), while the agreement between NT-proBNP methods was better. CardioOrmoCheck study demonstrates that there are marked differences in analytical performance and measured values in particular among commercialmethods for BNP assay. These findings suggest that it may be not reasonable to recommend identical cut-off or decision values for all BNP immunoassays

Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry

Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase

Evaluation of analytical performances using standardized analytical protocols and comparison of clinical results of the new ADVIA BNP and NT-proBNP immunoassays for the Centaur XPT platform

Background: The study aim was to evaluate and compare analytical performances and clinical results of ADVIA BNP and PBNP methods using the Centaur XPT platform with those of Access BNP, using the DxI platform and the ECLIA NT-proBNP method, using the Cobas e411 platform, respectively.Methods: Limits of blank (LoB), detection (LoD) and quantitation (LoQ) at 20% CV and 10% CV were evaluated according to international standardized protocols. The analytical parameters were assessed throughout a 90-working-day period using three curve calibrations.Results: LoB, LoD and LoQ at 20% CV and 10% values of the ADVIA BNP method were 1.0 ng/L, 2.0 ng/L, 3.7 ng/L and 10.2 ng/L, respectively; while those of the ADVIA PBNP method were 1.3 ng/L, 3.0 ng/L, 9.7 ng/L and 22.3 ng/L, respectively. The ADVIA BNP and PBNP methods were able to measure the clinical decision values suggested by international guidelines for diagnosis of heart failure (HF) with an imprecision <= 6%. BNP concentrations measured with the ADVIA and Access methods showed a close linear regression (R = 0.9923, n = 200); a close linear regression was also found between NT-proBNP concentrations measured with the ADVIA and ECLIA methods (R = 0.9954, n = 202). However, the ADVIA method measured significantly lower BNP values than the Access method (on average -20.9%), while ADVIA PBNP method measured significantly higher NT-proBNP concentrations than the ECLIA method (on average +17.8%).Conclusions: Analytical performances of the BNP and PBNP ADVIA methods are well in accordance with the quality specifications required by international guidelines for diagnosis and follow-up of patients with HF

Analysis of the 2010-2012 results of the multicenter external proficiency study for 25-hydroxyvitamin D

Background: Results collected from the 2010–2012 cycles of the ‘Immunocheck’ external quality assessment scheme for 25-hydroxyvitamin D, conducted by QualiMedLab CNR (Italy) and ProBioQual (France; 250 among Italian and French laboratories) are presented in this article. Methods: Details of how QualiMedLab operates can be found in QualiMedLab website. Results: Interlaboratory imprecision was 19 (2010), 15 (2011) and 13% (2012). The LIAISON® analyzer (DiaSorin, Italy) was the most utilized, followed by Roche (UK), ImmunoDiagnostic Systems methods (UK), ARCHITECT (Abbott, IL, USA), radioimmunoassay (DiaSorin) and others. The within-method variability between laboratories (percentage coefficient of variation) were 15, 12.7 versus 9.8% for LIAISON, 27.8, 16.5 versus 11.7% for Roche, 15, 12 versus 17% for ImmunoDiagnostic Systems and 17.4, 18.6 versus 17.5% for radioimmunoassay in the 2010, 2011 versus 2012 cycles, and 15 versus 8.9% for ARCHITECT in the 2011 versus 2012, respectively. Conclusion: Significant differences in specific samples and discrepancies between laboratories and methods still exist, making the actuation of appropriate external quality assessment schemes mandatory. </jats:p