Abstract：
BACKGROUND:The use of nonstandardized N-terminal pro-B-type natriuretic peptide (NT-proBNP) assays can contribute to the misdiagnosis of heart failure (HF). Moreover, there is yet to be established a common consensus regarding the circulating forms of NT-proBNP being used in current assays. We aimed to characterize and quantify the various forms of NT-proBNP in the circulation of HF patients. METHODS:Plasma samples were collected from HF patients (n = 20) at rest and stored at -80 °C. NT-proBNP was enriched from HF patient plasma by use of immunoprecipitation followed by mass spectrometric analysis. Customized homogeneous sandwich AlphaLISA® immunoassays were developed and validated to quantify 6 fragments of NT-proBNP. RESULTS:Mass spectrometry identified the presence of several N- and C-terminally processed forms of circulating NT-proBNP, with physiological proteolysis between Pro2-Leu3, Leu3-Gly4, Pro6-Gly7, and Pro75-Arg76. Consistent with this result, AlphaLISA immunoassays demonstrated that antibodies targeting the extreme N or C termini measured a low apparent concentration of circulating NT-proBNP. The apparent circulating NT-proBNP concentration was increased with antibodies targeting nonglycosylated and nonterminal epitopes (P < 0.05). CONCLUSIONS:In plasma collected from HF patients, immunoreactive NT-proBNP was present as multiple N- and C-terminally truncated fragments of the full length NT-proBNP molecule. Immunodetection of NT-proBNP was significantly improved with the use of antibodies that did not target these terminal regions. These findings support the development of a next generation NT-proBNP assay targeting nonterminal epitopes as well as avoiding the central glycosylated region of this molecule.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Foo JY,Wan Y,Schulz BL,Kostner K,Atherton J,Cooper-White J,Dimeski G,Punyadeera Cdoi
10.1373/clinchem.2012.200204subject
Has Abstractpub_date
2013-10-01 00:00:00pages
1523-31issue
10eissn
0009-9147issn
1530-8561pii
clinchem.2012.200204journal_volume
59pub_type
杂志文章abstract：:Urinary polyamines were measured by a fluorometric thin-layer chromatographic technique in samples collected daily throughout a single menstrual cycle by each of 13 healthy women. Polyamine excretion fluctuated considerably, but excretion of putrescine, spermidine, and spermine combined was consistently greatest durin...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-05-01 00:00:00
abstract：:Ethchlorvynol is a commonly abused sedative hypnotic. I report here a seven-day study of serum ethchlorvynol concentrations in a patient who had received an extreme overdose. These concentrations were correlated with the patient's response to stimuli. Serum ethchlorvynol concentrations were logarithmically related to ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-06-01 00:00:00
abstract：:Investigating the interference of danazol in testosterone radioimmunoassays, we measured serum testosterone concentrations in the serum of women receiving danazol, with three testosterone radioimmunoassay kits. All of these showed positive interference by danazol or its metabolites (or both). Values for testosterone o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-01-01 00:00:00
abstract：:A liquid-chromatographic technique with a post-column enzymatic reaction and fluorescence detection was validated for analysis of individual bile acids in the serum of rats. Extraction recoveries averaged 91.1% (SD 6.9%) for all bile acids. The assay was sensitive (minimum detection of 16.8 pmol per 100-microL injecti...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：BACKGROUND:Subfractions of HDL, particularly large HDL (HDL2), are inversely correlated with the severity of coronary artery disease (CAD). alpha-Tocopherol (AT) is the main lipid-soluble antioxidant in plasma. Results of a previous small study (n = 44) suggested that either a combination of an antioxidant cocktail [80...
journal_title：Clinical chemistry
pub_type： 杂志文章,随机对照试验
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abstract：:Hemoglobinometry according to the International Committee of Standardization in Hematology (ICSH) suffers from imprecision related to high sample dilution and from potential errors owing to sample turbidity. We have evaluated a new instrument, "HemoCue," that measures hemoglobin at two wavelengths as azide methemoglob...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-03-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：2001-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-03-01 00:00:00
abstract：:We describe a new and specific method for measurement of lecithin palmitic acid in amniotic fluid. Dipalmitoyl lecithin, the major alveolar surfactant, has previously been estimated by measuring the lecithin-sphingomyelin ratio, total lecithin, total phospholipid phosphorus, and (or) total palmitic acid. Our method is...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1977-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-05-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：10.1373/clinchem.2007.091496
更新日期：2008-01-01 00:00:00
abstract：:A new enzymic method is described for the determination of creatine in urine by continuous-flow analysis. The measurement is accomplished by transforming creatine to formaldehyde in reactions catalyzed by creatinase (creatine amidinohydrolase) and sarcosine dehydrogenase. The formaldehyde is reacted with 4-amino-3-hyd...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-11-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1093/clinchem/hvaa024
更新日期：2020-04-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-02-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1988-05-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章,评审
doi：
更新日期：1991-11-01 00:00:00
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journal_title：Clinical chemistry
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doi：10.1373/clinchem.2013.214213
更新日期：2014-05-01 00:00:00
abstract：:Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a recessively inherited defect in the mitochondrial beta-oxidation of fatty acids. A single nucleotide change, the A985 --> G transition, in the MCAD gene accounts for approximately 90% of all the disease-causing mutations in the patients. We have used PCR to am...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1996-09-01 00:00:00
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journal_title：Clinical chemistry
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journal_title：Clinical chemistry
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doi：
更新日期：1978-04-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1997-04-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1998-06-01 00:00:00
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更新日期：2013-06-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：2006-02-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
doi：10.1373/clinchem.2016.260471
更新日期：2017-01-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1984-04-01 00:00:00
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更新日期：2008-09-01 00:00:00
