{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T02:50:35Z","timestamp":1777431035843,"version":"3.51.4"},"reference-count":21,"publisher":"SAGE Publications","issue":"6","license":[{"start":{"date-parts":[[1997,11,1]],"date-time":"1997-11-01T00:00:00Z","timestamp":878342400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Ann Clin Biochem"],"published-print":{"date-parts":[[1997,11]]},"abstract":"<jats:p>\n                    We evaluated a novel assay for the measurement of 1,25 dihydroxyvitamin D (1,25 (OH)\n                    <jats:sub>2<\/jats:sub>\n                    D). Immunoextraction of 1,25 (OH)\n                    <jats:sub>2<\/jats:sub>\n                    D is performed using a mini column containing a solid-phase monoclonal antibody followed by radioimmunoassay (RIA) using an\n                    <jats:sup>125<\/jats:sup>\n                    I-labelled 1,25 (OH)\n                    <jats:sub>2<\/jats:sub>\n                    D derivative tracer and Sac-cell separation. The mean recovery of 1,25(OH)\n                    <jats:sub>2<\/jats:sub>\n                    D\n                    <jats:sub>3<\/jats:sub>\n                    was 101%, linearity was excellent, inter- and intra-assay coefficients of variation were 9, 8 and 13% and 11, 10 and 14% at low, medium and high concentrations of 1,25(OH)\n                    <jats:sub>2<\/jats:sub>\n                    D\n                    <jats:sub>3<\/jats:sub>\n                    , respectively. The cross-reactivity of vitamin D metabolites was &lt;0\u00b70015% for 25-hydroxyvitamin D\n                    <jats:sub>3<\/jats:sub>\n                    , 24, 25 dihydroxyvitamin D\n                    <jats:sub>3<\/jats:sub>\n                    and dihydrotachysterol and 0\u00b754% for l\u03b1 calcidol. 1,25 dihydroxyvitamin D\n                    <jats:sub>2<\/jats:sub>\n                    cross-reactivity was 79%. The detection limit of the assay was 5pmol\/L. Comparison with a commercial radio receptor assay (RRA) and an in-house RIA gave regression equations of y = 0\u00b794x+11\u00b78 ( r = 0\u00b798) and y = 0\u00b791x-1\u00b77 ( r = 0.95), respectively, with no major discrepancies between the methods in all patient groups studied. Plasma concentrations of 1,25 (OH)\n                    <jats:sub>2<\/jats:sub>\n                    D obtained with the assay were as follows: normal, unsupplemented subjects: mean 88, range 48\u2013155 pmol\/L, n = 68, patients with chronic renal failure: mean 11, range 3\u201336 pmol\/L, n = 27, primary hyperparathyroidism: mean 198, range 130\u2013299 pmol\/L, n = 23, Paget's disease: mean 92, range 42\u2013149 pmol\/L, n = 24, osteomalacia: mean 43, range 27\u201361 pmol\/L, n = 9. A minimum sample volume of 300 \u03bcL is required, the hands-on time is significantly less than other commercial assays and the measuring procedure is gamma counting rather than scintillation counting. The assay offers several advantages over previous methods and should allow more laboratories to offer measurement of 1,25 (OH)\n                    <jats:sub>2<\/jats:sub>\n                    D as part of their repertoire.\n                  <\/jats:p>","DOI":"10.1177\/000456329703400606","type":"journal-article","created":{"date-parts":[[2014,2,5]],"date-time":"2014-02-05T16:58:39Z","timestamp":1391619519000},"page":"632-637","source":"Crossref","is-referenced-by-count":56,"title":["Measurement of Plasma 1,25 Dihydroxyvitamin D Using a Novel Immunoextraction Technique and Immunoassay with Iodine Labelled Vitamin D Tracer"],"prefix":"10.1177","volume":"34","author":[{"given":"W D","family":"Fraser","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B H","family":"Durham","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J L","family":"Berry","sequence":"additional","affiliation":[{"name":"University Department of Medicine, Manchester Royal Infirmary, Manchester, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"E B","family":"Mawer","sequence":"additional","affiliation":[{"name":"University Department of Medicine, Manchester Royal Infirmary, Manchester, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[1997,11,1]]},"reference":[{"key":"bibr1-000456329703400606","first-page":"74","volume-title":"Primer on the Metabolic Bone Diseases and Disorders of Mineral Metabolism","author":"Holick MF","year":"1996","edition":"3"},{"key":"bibr2-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM198904133201506"},{"key":"bibr3-000456329703400606","first-page":"719","volume":"13","author":"Walters MR","year":"1992","journal-title":"Endocr Rev"},{"key":"bibr4-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2265.1976.tb03823.x"},{"key":"bibr5-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1172\/JCI108459"},{"key":"bibr6-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1016\/0003-9861(76)90161-2"},{"key":"bibr7-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1210\/jcem-58-1-91"},{"key":"bibr8-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1210\/jcem-56-4-751"},{"key":"bibr9-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/26.5.562"},{"key":"bibr10-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2265.1983.tb02977.x"},{"key":"bibr11-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1016\/0009-8981(90)90174-Q"},{"key":"bibr12-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/42.4.586"},{"key":"bibr13-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1210\/jcem-46-6-891"},{"key":"bibr14-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/25.4.584"},{"key":"bibr15-000456329703400606","first-page":"765","volume-title":"Vitamin D: A Pluripotent Steroid Hormone.","author":"Berry JL","year":"1994"},{"key":"bibr16-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/32.11.2060"},{"key":"bibr17-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1016\/S0140-6736(73)92197-1"},{"key":"bibr18-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1159\/000181749"},{"key":"bibr19-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1111\/j.1365-2265.1980.tb02704.x"},{"key":"bibr20-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.69.7.1673"},{"key":"bibr21-000456329703400606","doi-asserted-by":"publisher","DOI":"10.1093\/clinchem\/41.9.1313"}],"container-title":["Annals of Clinical Biochemistry: International Journal of Laboratory Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/000456329703400606","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1177\/000456329703400606","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T11:44:01Z","timestamp":1777376641000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1177\/000456329703400606"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1997,11]]},"references-count":21,"journal-issue":{"issue":"6","published-print":{"date-parts":[[1997,11]]}},"alternative-id":["10.1177\/000456329703400606"],"URL":"https:\/\/doi.org\/10.1177\/000456329703400606","relation":{},"ISSN":["0004-5632","1758-1001"],"issn-type":[{"value":"0004-5632","type":"print"},{"value":"1758-1001","type":"electronic"}],"subject":[],"published":{"date-parts":[[1997,11]]}}}