69 research outputs found
Multicentre evaluation of a new point-of-care test for the determination of NT-proBNP in whole blood
Background: The Roche CARDIAC proBNP point-of-care (POC) test is the first test intended for the quantitative determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) in whole blood as an aid in the diagnosis of suspected congestive heart failure, in the monitoring of patients with compensated left-ventricular dysfunction and in the risk stratification of patients with acute coronary syndromes. Methods: A multicentre evaluation was carried out to assess the analytical performance of the POC NT-proBNP test at seven different sites. Results: The majority of all coefficients of variation (CVs) obtained for within-series imprecision using native blood samples was below 10% for both 52 samples measured ten times and for 674 samples measured in duplicate. Using quality control material, the majority of CV values for day-to-day imprecision were below 14% for the low control level and below 13% for the high control level. In method comparisons for four lots of the POC NT-proBNP test with the laboratory reference method (Elecsys proBNP), the slope ranged from 0.93 to 1.10 and the intercept ranged from 1.8 to 6.9. The bias found between venous and arterial blood with the POC NT-proBNP method was â¤5%. All four lots of the POC NT-proBNP test investigated showed excellent agreement, with mean differences of between â5% and +4%. No significant interference was observed with lipaemic blood (triglyceride concentrations up to 6.3mmol/L), icteric blood (bilirubin concentrations up to 582Îźmol/L), haemolytic blood (haemoglobin concentrations up to 62mg/L), biotin (up to 10mg/L), rheumatoid factor (up to 42IU/mL), or with 50 out of 52 standard or cardiological drugs in therapeutic concentrations. With bisoprolol and BNP, somewhat higher bias in the low NT-proBNP concentration range (<175ng/L) was found. Haematocrit values between 28% and 58% had no influence on the test result. Interference may be caused by human anti-mouse antibodies (HAMA) types 1 and 2. No significant influence on the results with POC NT-proBNP was found using volumes of 140-165ÎźL. High NT-proBNP concentrations above the measuring range of the POC NT-proBNP test did not lead to false low results due to a potential high-dose hook effect. Conclusions: The POC NT-proBNP test showed good analytical performance and excellent agreement with the laboratory method. The POC NT-proBNP assay is therefore suitable in the POC setting. Clin Chem Lab Med 2006;44:1269-7
Multi-omics for studying and understanding polar life
Polar ecosystems are experiencing amongst the most rapid rates of regional warming on Earth. Here, we discuss âomicsâ approaches to investigate polar biodiversity, including the current state of the art, future perspectives and recommendations. We propose a community road map to generate and more fully exploit multi-omics data from polar organisms. These data are needed for the comprehensive evaluation of polar biodiversity and to reveal how life evolved and adapted to permanently cold environments with extreme seasonality. We argue that concerted action is required to mitigate the impact of warming on polar ecosystems via conservation efforts, to sustainably manage these unique habitats and their ecosystem services, and for the sustainable bioprospecting of novel genes and compounds for societal gain
Fungus-Specific SSR Markers in the Antarctic Lichens Usnea antarctica and U. aurantiacoatra (Parmeliaceae, Ascomycota)
Premise of the study: Usnea antarctica and U. aurantiacoatra (Parmeliaceae) are common lichens in the maritime Antarctic. These species share the same habitats on King George Island (South Shetland Islands, Antarctica) and are distinguishable based on reproductive strategies. Methods and Results: We developed 23 fungus-specific simple sequence repeat (SSR) markers that cross-Amplify between the two species. We used a low-coverage genome-skimming approach on one sample of each species to identify SSR repeats in the two species. Primers were designed for 3-4-bp repeats, and only the loci common to both species were selected for further analyses. Seventy-seven samples of the two species were selected to assess fungal specificity, genetic variability, and linkage of the markers. In addition, we tested cross-Amplification in other Usnea species. Conclusions: The 23 newly designed SSR markers are suitable for population genetic and phylogeographic studies of Usnea species
The use of microsatellite markers for species delimitation in Antarctic Usnea subgenus Neuropogon
Lichens are symbiotic associations consisting of a fungal (mycobiont) and one or more photosynthetic (photobionts) partners and are the dominant component, and most important primary producers, of Antarctic terrestrial ecosystems. The most common lichens in the maritime Antarctic are Usnea antarctica and U. aurantiacoatra, a so-called âspecies pairâ in which U. antarctica shows asexual reproduction and propagation via soredia and U. aurantiacoatra forms ascospores in apothecia. Previous molecular analyses were not able to unambiguously distinguish the two morphotypes as species. Therefore, the goal of this study was to find out whether fast-evolving SSR (single sequence repeat) markers are able to separate morphotypes more clearly and help to clarify their taxonomy. We investigate 190 individuals from five mixed stands of both morphotypes collected in King George Island and Elephant Island (South Shetland Islands, Antarctica). Based on 23 microsatellite markers designed from sequenced genomes, discriminant analysis of principal components (DAPC), Bayesian clustering analysis, and coalescent-based estimation of gene flow show clear evidence for the existence of two different species distinguishable by reproductive mode. We did not detect any statistical association between genetic clusters and three previously reported chemical races of each species
Alphaproteobacterial communities in geographically distant populations of the lichen Cetraria aculeata.
Lichen symbioses were recently shown to include diverse bacterial communities.
Although the biogeography of lichen species is fairly well known, the
patterns of their bacterial associates are relatively poorly understood. Here we
analyse the composition of Alphaproteobacteria in Cetraria aculeata, a common
lichen species that occurs at high latitudes and various habitats. Using clone
libraries we show that most of the associated Alphaproteobacteria belong to
Acetobacteraceae, which have also been found previously in other lichen species
of acidic soils and rocks in alpine habitats. The majority of alphaproteobacterial
sequences from C. aculeata are very similar to each other and form a single
clade. Data from C. aculeata reveal that alphaproteobacterial communities of
high latitudes are depauperate and more closely related to each other than to
those of extrapolar habitats. This agrees with previous findings for the fungal
and algal symbiont in this lichen. Similar to the algal partner, the composition
of lichen alphaproteobacterial communities is affected by environmental
parameters
Role of procalcitonin and granulocyte colony stimulating factor in the early prediction of infected necrosis in severe acute pancreatitis
BACKGROUNDâInfected pancreatic necrosis (IPN) is the main cause of death in patients with severe acute pancreatitis. Therefore an early prediction of IPN is of utmost importance.â¨AIMâAnalysis of new blood variables as potential early predictors to differentiate between IPN and sterile pancreatic necrosis (SPN).â¨PATIENTSâ64 consecutive patients with acute pancreatitis were enrolled in this prospective study; 29 were suffering from acute oedematous pancreatitis (AIP), and 35 from necrotising disease (NP) as diagnosed by contrast enhanced computed tomography.â¨METHODSâProcalcitonin (PCT) and granulocyte colony stimulating factor (G-CSF) in the serum were examined and compared with C reactive protein (CRP). CRP was measured with a turbidimetric immunoassay (Autokit CRP; Wako, Osaka, Japan), and PCT and G-CSF by ELISA (Lumitest PCT; Brahms Diagnostica, Berlin, Germany; G-CSF-Elisa; R&D Systems, Abingdon, Oxon, UK). Monitoring was performed daily and related to the onset of symptoms.â¨RESULTSâWithin the first week, all three variables (CRP, PCT, and G-CSF) were significantly higher in patients with NP than in those with AIP (CRP, p<0.001; G-CSF, p<0.001; PCT, p<0.001). During the course of the study, 12 of the 35 patients with NP developed late IPN after a median of 20.5 (range 3-49) days. Neither the peak nor the lowest concentrations during the monitoring period were of any value for predicting IPN (median peak values in SPN v IPN: PCT, 0.93 v 1.93 ng/ml; G-CSF, 347 v 421 pg/ml; CRP, 270( )v 325 mg/l).â¨CONCLUSIONSâSerum PCT, G-CSF, and CRP concentrations are of similar value for early differentiation between mild and severe acute pancreatitis. However, these variables are not suitable for the early prediction of IPN.â¨â¨â¨Keywords: pancreatitis; procalcitonin; granulocyte colony stimulating factor; C reactive protein; infected pancreatic necrosis; prognosi
Multicentre evaluation of a new point-of-care test for the determination of NT-proBNP in whole blood
Background: The Roche CARDIAC proBNP point-of-care (POC) test is the first test intended for the quantitative determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) in whole blood as an aid in the diagnosis of suspected congestive heart failure, in the monitoring of patients with compensated left-ventricular dysfunction and in the risk stratification of patients with acute coronary syndromes.
Methods: A multicentre evaluation was carried out to assess the analytical performance of the POC NT-proBNP test at seven different sites.
Results: The majority of all coefficients of variation (CVs) obtained for within-series imprecision using native blood samples was below 10% for both 52 samples measured ten times and for 674 samples measured in duplicate. Using quality control material, the majority of CV values for day-to-day imprecision were below 14% for the low control level and below 13% for the high control level. In method comparisons for four lots of the POC NT-proBNP test with the laboratory reference method (Elecsys proBNP), the slope ranged from 0.93 to 1.10 and the intercept ranged from 1.8 to 6.9. The bias found between venous and arterial blood with the POC NT-proBNP method was â¤5%. All four lots of the POC NT-proBNP test investigated showed excellent agreement, with mean differences of between â5% and +4%. No significant interference was observed with lipaemic blood (triglyceride concentrations up to 6.3mmol/L), icteric blood (bilirubin concentrations up to 582Îźmol/L), haemolytic blood (haemoglobin concentrations up to 62mg/L), biotin (up to 10mg/L), rheumatoid factor (up to 42IU/mL), or with 50 out of 52 standard or cardiological drugs in therapeutic concentrations. With bisoprolol and BNP, somewhat higher bias in the low NT-proBNP concentration range (<175ng/L) was found. Haematocrit values between 28% and 58% had no influence on the test result. Interference may be caused by human anti-mouse antibodies (HAMA) types 1 and 2. No significant influence on the results with POC NT-proBNP was found using volumes of 140â165ÎźL. High NT-proBNP concentrations above the measuring range of the POC NT-proBNP test did not lead to false low results due to a potential high-dose hook effect.
Conclusions: The POC NT-proBNP test showed good analytical performance and excellent agreement with the laboratory method. The POC NT-proBNP assay is therefore suitable in the POC setting
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