{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T20:32:01Z","timestamp":1777926721083,"version":"3.51.4"},"reference-count":0,"publisher":"S. Karger AG","license":[{"start":{"date-parts":[[2009,9,18]],"date-time":"2009-09-18T00:00:00Z","timestamp":1253232000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"},{"start":{"date-parts":[[2009,9,18]],"date-time":"2009-09-18T00:00:00Z","timestamp":1253232000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/karger.com\/pages\/terms-and-conditions"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biol Neonate"],"abstract":"<jats:p>We assayed digoxin-like immunoreactivity in the serum of 19 healthy neonates (blood sample from umbilical cord), not receiving digoxin therapy, using a solid-phase radioimmunological method. In addition, urinary concentrations of a digoxin-like immunoreactive substance (DLIS) were assayed throughout the first 10 weeks of extrauterine life in 50 healthy infants. The mean ( \u00b1 SD) serum DLIS concentration obtained was 211 \u00b1 60 ng\/l digoxin equivalents (d.e.) while, in the urinary samples of the first day of life, the mean concentration was 818 \u00b1 560 ng\/l d.e. (n = 20). These DLIS values in infants were higher (about 5- to 10-fold) than those previously observed in adults. In addition, urinary DLIS values were very high in the first week of life and fell quite rapidly in the next weeks of life. We used serum and urine pools from neonates for gel filtration experiments using a Sephadex G 25 column. In the urine sample we found some immunoreactive peaks eluted at the end and after the region of salts, while the chromatographic profiles of the serum pool showed only a major peak eluted with the peak of proteins. After boiling, the same serum pool showed an elution pattern characterized by a smaller immunoreactive peak eluted with that of proteins and by other peaks similar to those observed for the urine sample. Our study demonstrated that a substance or more substances which cross-react with digoxin-specific antibodies are present in blood and urine of healthy infants. In addition, our chromatographic studies indicate that DLIS is probably a low molecular weight substance(s) which circulate(s) in blood bound to a higher molecular weight molecule.<\/jats:p>","DOI":"10.1159\/000242119","type":"journal-article","created":{"date-parts":[[2009,9,23]],"date-time":"2009-09-23T13:35:09Z","timestamp":1253712909000},"page":"217-222","source":"Crossref","is-referenced-by-count":3,"title":["Chromatographic Characterization of Endogenous Digoxin-Like Immunoreactive Substances Present in Serum and Urine of Infants Using Gel Filtration with Sephadex G 25"],"prefix":"10.1159","author":[{"given":"Aldo","family":"Clerico","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Boldrini","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silvana","family":"Balzan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pascal","family":"Biver","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Massimo","family":"Fantoni","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"127","published-online":{"date-parts":[[2009,9,18]]},"container-title":["Biology of the Neonate"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.karger.com\/Article\/Pdf\/242119","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/karger.com\/article-pdf\/doi\/10.1159\/000242119","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T22:18:35Z","timestamp":1777673915000},"score":1,"resource":{"primary":{"URL":"https:\/\/karger.com\/article\/doi\/10.1159\/000242119"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,9,18]]},"references-count":0,"URL":"https:\/\/doi.org\/10.1159\/000242119","archive":["Portico"],"relation":{},"ISSN":["0006-3126","1421-9727"],"issn-type":[{"value":"0006-3126","type":"print"},{"value":"1421-9727","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,9,18]]}}}