Abstract：
BACKGROUND:24,25-Dihydroxyvitamin D [24,25(OH)2D] in serum may be both a nuisance and nutritionally valuable. METHODS:We investigated the impact of 24,25(OH)2D3 on the performance of commercially available immunoassays for serum total 25-hydroxyvitamin D [25(OH)D] using (a) serum from a nationally representative sample of adults, (b) serum from a spiking experiment, and (c) data from the UK Vitamin D External Quality Assurance Scheme (DEQAS). We also investigated the utility of the serum ratio of 24,25(OH)2D3 to 25(OH)D as an index of inactivation and of response to vitamin D supplementation using randomized controlled trial (RCT) data. Measurement of 24,25(OH)2D in sera by a LC-MS/MS method allowed for an investigation of its impact on immunoassay-derived serum 25(OH)D values as well as its clinical utility. We report data from a nationally representative sample of adults, a recent vitamin D RCT in older adults, and DEQAS. RESULTS:24,25(OH)2D3 contributed to the positive bias observed in some immunoassays relative to LC-MS/MS-derived estimates for total 25(OH)D. A spiking experiment showed that the degree of cross-reactivity with 24,25(OH)2D was high and may underpin this positive bias. Adjustment for 24,25(OH)2D3 concentration brought estimates closer to true values. Data from the vitamin D RCT showed that the ratio of 24,25(OH)2D3 to 25(OH)D was associated with serum 25(OH)D3 and with response of serum 25(OH)D to vitamin D supplementation. CONCLUSIONS:Our findings highlight that the effect of 24,25(OH)2D3 in serum is a double-edged sword-an interferent for some immunoassays, yet potentially informative of nutritional status.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Cashman KD,Hayes A,Galvin K,Merkel J,Jones G,Kaufmann M,Hoofnagle AN,Carter GD,Durazo-Arvizu RA,Sempos CTdoi
10.1373/clinchem.2014.234955subject
Has Abstractpub_date
2015-04-01 00:00:00pages
636-45issue
4eissn
0009-9147issn
1530-8561pii
clinchem.2014.234955journal_volume
61pub_type
杂志文章,随机对照试验abstract：BACKGROUND:Adequate detection of designer steroids in the urine of athletes is still a challenge in doping control analysis and requires knowledge of steroid metabolism. In this study we investigated whether uPA(+/+)-SCID mice carrying functional primary human hepatocytes in their liver would provide a suitable alterna...
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doi：10.1373/clinchem.2008.119396
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abstract：BACKGROUND:Laboratory tests can be an important source of blood loss in hospitals, especially for newborns and patients in intensive care. The aim of this study was to quantify blood loss for laboratory diagnostic tests in a large number of patients in a teaching hospital. METHODS:We estimated blood loss by multiplyin...
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abstract：BACKGROUND:Plasma B-type cardiac natriuretic peptides reflect cardiac structure and function and have proven roles in assisting in the diagnosis of acute heart failure. They are independent prognostic indicators across the full spectrum of cardiovascular disease. Serial changes in plasma B-type cardiac natriuretic pept...
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pub_type： 杂志文章,评审
doi：10.1373/clinchem.2011.165704
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abstract：BACKGROUND:Current noninvasive assays for urothelial carcinoma (UC) lack clinical sensitivity and specificity. Given the utility of plasma cell-free DNA (cfDNA) biomarkers, the development of urinary cfDNA biomarkers may improve the diagnostic sensitivity. METHODS:We assessed copy number alterations (CNAs) by shallow ...
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1975-03-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1993-12-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1981-03-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
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：1989-08-01 00:00:00
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pub_type： 临床试验,杂志文章,随机对照试验
doi：
更新日期：1993-09-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1999-11-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1979-02-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1988-01-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1978-03-01 00:00:00
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doi：
更新日期：1997-09-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1986-01-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1985-03-01 00:00:00
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doi：
更新日期：1992-05-01 00:00:00
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更新日期：1996-10-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1982-11-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1990-08-01 00:00:00
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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
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doi：
更新日期：1986-06-01 00:00:00
