Abstract:
:Assays with different specificity are used for cyclosporin monitoring in clinical transplantation. A recent survey of 35 centers showed that 86% used immunoassays for cyclosporin A (CsA). In consensus documents the following performance criteria were recommended: (a) imprecision < or = 10% at 50 microg/L and < or = 5% at 300 microg/L; and (b) comparison with the reference method (HPLC) should yield a slope of 0.9-1.1, an intercept of -15 to 15 microg/L, and S(y/x) < or = 15 microg/L. The newly developed CsA assays for the AxSYM (Abbott) and the CEDIA (Boehringer Mannheim) as well as the Emit assay (Behring Diagnostica) were evaluated. Results from samples of heart, kidney, and liver recipients (100 specimens each) were compared with a validated HPLC-ultraviolet detection method. Between-series imprecision (CV) with commercial controls was 5.8% and 1.7% for AxSYM (70 and 300 microg/L), 11% and 5.5% for CEDIA (90 and 200 microg/L), and 8.1% and 4.5% for Emit (63 and 172 microg/L). In the presence of 300 microg/L parent CsA, cross-reactivities were (for AxSYM, CEDIA, and Emit, respectively) 7%, 4%, and none for AM1 (1 mg/L) and 12.6%, 25%, and 6% for AM9 (0.5 mg/L). Comparison with HPLC showed in heart and kidney recipients an average overestimation with the Emit and the CEDIA of approximately 22%, with overestimation in the AxSYM of 32%. In liver recipients, the most challenging patient group, the CEDIA and the AxSYM showed a mean overestimation of 43% and 47%, respectively, and the Emit differed by 31% compared with HPLC. None of the immunoassays fully satisfied the performance criteria recommended in the consensus documents. In terms of specificity, Emit ranks before CEDIA, which ranks before AxSYM. Regarding imprecision, the ranking is AxSYM < Emit < CEDIA. These limitations must be considered when using these assays for therapeutic drug monitoring of CsA in clinical transplantation.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Schütz E,Svinarov D,Shipkova M,Niedmann PD,Armstrong VW,Wieland E,Oellerich Msubject
Has Abstractpub_date
1998-10-01 00:00:00pages
2158-64issue
10eissn
0009-9147issn
1530-8561journal_volume
44pub_type
杂志文章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 fai...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2013.210435
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doi:10.1373/clinchem.2006.083360
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journal_title:Clinical chemistry
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2016.270140
更新日期:2017-07-01 00:00:00
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journal_title:Clinical chemistry
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doi:
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pub_type: 杂志文章
doi:10.1373/clinchem.2004.032292
更新日期:2004-05-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-03-01 00:00:00
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journal_title:Clinical chemistry
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doi:
更新日期:1992-10-01 00:00:00
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journal_title:Clinical chemistry
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2008.112425
更新日期:2009-03-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1988-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1373/clinchem.2017.281469
更新日期:2018-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1985-07-01 00:00:00
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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:1990-01-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:2000-08-01 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
abstract::To determine the molar absorptivities of beta-NADH and beta-NAD at 260 nm, we purified the reduced form of the coenzyme by repeated anion-exchange chromatography. A NADH preparation was so obtained for which the 260 nm/340 nm absorbance ratio was 2.265. When calculated with epsilon 340 beta-NADH = 6.22 times 10-3 for ...
journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1975-06-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1980-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:10.1373/clinchem.2003.029223
更新日期:2004-08-01 00:00:00
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pub_type: 杂志文章,评审
doi:
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journal_title:Clinical chemistry
pub_type: 杂志文章
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更新日期:2010-09-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1992-12-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1977-05-01 00:00:00
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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: 临床试验,杂志文章
doi:
更新日期:1999-10-01 00:00:00
abstract::gamma-Aminobutyric acid (GABA), an inhibitory neurotransmitter that serves about one-third of brain neurons, is involved in the development of depression and in the treatment of depression and mania with pharmacological therapy. Brain activity of GABA may be conveniently measured in plasma, and changes in plasma conce...
journal_title:Clinical chemistry
pub_type: 杂志文章,评审
doi:
更新日期:1994-02-01 00:00:00
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journal_title:Clinical chemistry
pub_type: 杂志文章
doi:
更新日期:1994-04-01 00:00:00