Abstract：
BACKGROUND:The B-type natriuretic peptides (BNP and N-terminal pro-BNP) are secreted by the heart and, in the case of BNP, serve to maintain circulatory homeostasis through renal and vascular actions and oppose many effects of the renin-angiotensin system. Recent evidence suggests that in patients with severe heart failure, circulating immunoreactive BNP is made up mainly of metabolites that may have reduced bioactivity. We hypothesized that BNP may be degraded before it even leaves the heart. METHODS:Peripheral venous plasma plus atrial and ventricular tissue, obtained from explanted hearts at the time of transplantation, were collected from 3 patients with end-stage heart failure. In a separate study, plasma was collected from the coronary sinus and femoral artery of 3 separate patients undergoing cardiac catheterization. Plasma C18 reverse-phase extracts were separated on reverse-phase HPLC, and the collected fractions were subjected to RIAs with highly specific antisera directed to the amino- and carboxy-terminal ends of BNP(1-32). RESULTS:ProBNP, BNP(1-32), and 2 major BNP metabolites were present in atrial and ventricular tissue, where BNP(1-32) represented 45% and 70% of total processed BNP, respectively. Neither BNP(1-32) nor the 2 metabolites were detected in peripheral venous plasma. Nor was BNP(1-32) detected in matching coronary sinus and femoral artery plasma from the 3 patients undergoing cardiac catheterization. CONCLUSIONS:BNP(1-32) is partly degraded within the hearts of patients with end-stage heart failure, and even in patients with relatively well-preserved left ventricular systolic function, only BNP metabolites enter the systemic circulation.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Mahagamasekera PG,Ruygrok PN,Palmer SC,Richards AM,Ansell GS,Nicholls MG,Pemberton CJ,Lewis LK,Yandle TGdoi
10.1373/clinchem.2013.210435subject
Has Abstractpub_date
2014-03-01 00:00:00pages
549-58issue
3eissn
0009-9147issn
1530-8561pii
clinchem.2013.210435journal_volume
60pub_type
杂志文章abstract：:We have modified an automated measurement system of urinary iodine (UI) and established a sensitive UI assay system by using ultraviolet (UV) digestion. The automated system is sensitive enough to detect concentrations of UI < 0.78 mumol/L (< 10 micrograms/dL) in a small volume of urine (500 microL). Sample throughput...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-04-01 00:00:00
abstract：:We report the production and comparative specificities of antisera raised to different immunogens containing codeine, morphine, and oxycodone. Antisera raised to bovine serum albumin (BSA) conjugates of codeine-6-hemisuccinate, ethylmorphine-6-hemisuccinate, or oxycodone-6-carboxymethyloxime had greatest recognition o...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-09-01 00:00:00
abstract：:We used ion-exchange column chromatography and electrophoresis on polyacrylamide gel to compare the acid phosphatase isoenzymes of prostate and leukocytes. The major isoenzyme of the prostate is band 2A; only a trace of band 2B was observed. However, the major isoenzymes of leukocytes are band 4 and band 2B, and only ...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1979-07-01 00:00:00
abstract：:The molar absorptivity of unconjugated bilirubin in caffeine reagent is independent of the protein matrix. This finding, together with the simplicity of a dilution step for direct spectrophotometry, will improve the calibration methods of bilirubin and make them more nearly accurate. This is encouraging for the develo...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-07-01 00:00:00
abstract：:Highly purified human lactate dehydrogenases I and V were assayed in 17 different buffers, at a variety of reaction pH's. Diethanolamine and 2-amino-2-methyl-1,3-propanediol provided the best measurements of the enzyme, assayed lactate-to-pyruvate. However, the commercial preparation of 2-amino-2-methyl-1,3-propanedio...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-11-01 00:00:00
abstract：:We have developed and thoroughly validated radioimmunoassays (RIAs) for osteocalcin in plasma and serum, demonstrating independence of volume and determining the recovery of added standard and within- and between-assay precision. Antibodies were raised in rabbits and mice by immunization with either osteocalcin adsorb...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1989-07-01 00:00:00
abstract：BACKGROUND:Increased concentrations of cell-free DNA have been found in several disorders and have been interpreted as evidence of increased rates of cell death or turnover. Evidence from in vitro and animal experiments suggests that DNA may play a role in the pathogenesis of rheumatoid arthritis (RA). METHODS:We meas...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.084509
更新日期：2007-09-01 00:00:00
abstract：:A "sandwich" enzyme immunoassay for ferritin in human serum is described, in which horseradish peroxidase-labeled antibody and a very sensitive chromogen, 2,2'-azino-di(3-ethyl-benzthiazolin-6-sulfonate), are used. The solid phase is polypropylene test tubes treated with glutaraldehyde; immunologic reactions are devel...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-04-01 00:00:00
abstract：:A literature review of the effects of long-term freezer storage on concentrations of antioxidant micronutrients in serum or plasma showed that a high proportion of the studies that compared the concentrations of retinol, beta-carotene, or alpha-tocopherol in fresh and stored serum were deficient because of small numbe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-06-01 00:00:00
abstract：:Investigating the feasibility and validity of determining plasma ferritin concentration in blood obtained by finger prick, we studied 29 adults (ages 21-49 years) and 35 children (ages 14-66 months). Blood was sampled simultaneously in the same subject from both the antecubital vein (venous blood) and by finger pricki...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-05-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1990-06-01 00:00:00
abstract：BACKGROUND:The recent development of nonradioactive automated assays for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D (25OHD) has made measurement of these two hormones possible in many laboratories. In this study, we compared two new assays for PTH and 25OHD adapted on an automated analyzer, the LIAISON, wi...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2004.037606
更新日期：2005-02-01 00:00:00
abstract：BACKGROUND:The Dutch project "Calibration 2000" aims at harmonization of laboratory results via calibration by development of matrix-based secondary reference materials. We considered the selection, preparation, and characterization of 34 potential reference materials (PRMs). METHODS:Sixteen PRMs were prepared either ...
journal_title：Clinical chemistry
pub_type： 杂志文章,多中心研究
doi：
更新日期：2002-09-01 00:00:00
abstract：:We developed a novel noncompetitive immunoassay format for monoepitopic analytes and describe here a model assay for triiodothyronine (T3), performed on Ciba Corning's ACS:180 analyzer. Acridinium ester (AE)-labeled bivalent anti-T3 was incubated with the sample, producing AE-anti-T3/T3 complexes and unreacted AE-anti...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1995-07-01 00:00:00
abstract：:Changes in values for myoglobin, total creatine kinase (EC 2.7.3.2), and creatine kinase B-subunit in the serum of patients with thyroid disease are compared with values for these during the 24-h after myocardial infarction. Concentrations of all three of these muscle-derived proteins were significantly higher than no...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：10.1373/clinchem.2006.079012
更新日期：2007-04-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-02-01 00:00:00
abstract：:We have designed and constructed a digital matrix photometer for quantitative measurement of reflected light of small chromophoric areas or colored spots. The areas are divided conceptually into small subunits in which the reflected light is measured. This is done through stepwise scanning with a photodiode array. The...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-06-01 00:00:00
abstract：BACKGROUND:Increasing numbers of patients are presenting worldwide to emergency departments with suspected myocardial infarction. The use of point-of-care troponin assays might enable faster decision-making in this high-risk population and reduce the burden on emergency facilities. Here, we evaluate the diagnostic perf...
journal_title：Clinical chemistry
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doi：10.1373/clinchem.2019.307405
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1994-08-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1992-09-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1984-11-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-12-01 00:00:00
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journal_title：Clinical chemistry
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journal_title：Clinical chemistry
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doi：10.1373/clinchem.2007.085316
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-11-01 00:00:00
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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
pub_type： 杂志文章
doi：
更新日期：1997-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1986-04-01 00:00:00
