{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T18:41:58Z","timestamp":1780598518504,"version":"3.54.1"},"reference-count":22,"publisher":"Wiley","issue":"4","license":[{"start":{"date-parts":[[2008,6,28]],"date-time":"2008-06-28T00:00:00Z","timestamp":1214611200000},"content-version":"vor","delay-in-days":4106,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Clinical Genetics"],"published-print":{"date-parts":[[1997,4]]},"abstract":"<jats:p>Classical phenylketonuria (PKU) is an inborn error of metabolism of autosomal recessive inheritance characterized by the accumulation of phenylalanine (Phe) in tissues due to Phe\u20104\u2010hydroxylase deficiency. Several methods have been developed for the detection of PKU heterozygotes based on the determination of plasma Phe and tyrosine (Tyr) levels, on the analysis of the Phe\/Tyr and Phe<jats:sup>2<\/jats:sup>\/Tyr ratios and on the use of discriminant functions. The objective of the present study was to test the value of loading with aspartame (a sweetener consisting of Phe, aspartate and methanol) for the identification of PKU carriers. The study was conducted on 22 obligate heterozygotes and 27 controls. Two blood samples were collected (under fasting conditions and 30 min after the loading) for fluorometric determination of Phe and Tyr. Phe, Phe\/Tyr and Phe<jats:sup>2<\/jats:sup>\/Tyr values were higher in heterozygotes, whereas Tyr was higher in controls in both situations investigated. Linear discriminant function was considered to be the best parameter for differentiation of the individuals in the two groups. Under the conditions employed in the present study, aspartame loading did not show any advantages in discriminating between PKU carriers and normal individuals when compared to the same analysis performed under fasting conditions.<\/jats:p>","DOI":"10.1111\/j.1399-0004.1997.tb02460.x","type":"journal-article","created":{"date-parts":[[2010,7,19]],"date-time":"2010-07-19T10:14:25Z","timestamp":1279534465000},"page":"231-235","source":"Crossref","is-referenced-by-count":5,"title":["Evaluation of an aspartame loading test for the detection of heterozygotes for classical phenylketonuria"],"prefix":"10.1111","volume":"51","author":[{"given":"L C. S.","family":"Silva","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. F.","family":"Pires","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. C.","family":"Coelho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L B.","family":"Jardim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R.","family":"Giugliani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2008,6,28]]},"reference":[{"key":"e_1_2_1_1_1","doi-asserted-by":"publisher","DOI":"10.1016\/0026-0495(94)90068-X"},{"key":"e_1_2_1_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-3476(86)80239-6"},{"key":"e_1_2_1_3_1","first-page":"123","article-title":"Heterozygote detection in two hyperphenylalaninemia types: classic phenylketonuria and Dihydrobiopterin in biosynthesis deficiency","volume":"9","author":"Coelho\u2010Dutra J","year":"1986","journal-title":"Rev Bras Gen\u00e9t"},{"key":"e_1_2_1_4_1","first-page":"646","article-title":"Classical phenylketonuria: heterozygote detection during pregnancy","volume":"25","author":"Griffin RF","year":"1973","journal-title":"Am J Hum Genet"},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF01799943"},{"key":"e_1_2_1_6_1","doi-asserted-by":"crossref","first-page":"1661","DOI":"10.1093\/clinchem\/23.9.1661","article-title":"Detection of heterozygotes for phenylketonuria by constant intravenous infusion of L\u2010phenylalanine","volume":"23","author":"Jagenburg R","year":"1977","journal-title":"Clin Chem"},{"key":"e_1_2_1_7_1","doi-asserted-by":"publisher","DOI":"10.1080\/15287397609529446"},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/0009-8981(84)90354-1"},{"key":"e_1_2_1_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/S0022-3476(89)80431-7"},{"key":"e_1_2_1_10_1","first-page":"170","article-title":"Aspartame: un nuevo edulcorante","volume":"36","author":"Luco I","year":"1989","journal-title":"Bol Hosp S J De Dios"},{"key":"e_1_2_1_11_1","first-page":"885","article-title":"Fluorometric method for the determination of phenylalanine in serum","volume":"59","author":"McCaman M","year":"1962","journal-title":"J Lab Clin Med"},{"key":"e_1_2_1_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/0009-8981(67)90324-5"},{"key":"e_1_2_1_13_1","volume-title":"Manual of fluorimetric clinical procedures","author":"Philips RE.","year":"1967"},{"key":"e_1_2_1_14_1","doi-asserted-by":"publisher","DOI":"10.1203\/00006450-196907000-00004"},{"key":"e_1_2_1_15_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1399-0004.1988.tb03444.x"},{"key":"e_1_2_1_16_1","first-page":"1015","volume-title":"The metabolic and molecular bases of inherited disease","author":"Scriver CR","year":"1995"},{"key":"e_1_2_1_17_1","first-page":"381","volume-title":"Statistical methods","author":"Snedecor GW","year":"1973"},{"key":"e_1_2_1_18_1","doi-asserted-by":"publisher","DOI":"10.1093\/jn\/109.4.708"},{"key":"e_1_2_1_19_1","doi-asserted-by":"publisher","DOI":"10.1093\/jn\/110.11.2216"},{"key":"e_1_2_1_20_1","doi-asserted-by":"publisher","DOI":"10.1093\/jn\/117.11.1989"},{"key":"e_1_2_1_21_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1399-0004.1983.tb01858.x"},{"key":"e_1_2_1_22_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00201660"}],"container-title":["Clinical Genetics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1111%2Fj.1399-0004.1997.tb02460.x","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1111\/j.1399-0004.1997.tb02460.x","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,27]],"date-time":"2023-10-27T10:53:25Z","timestamp":1698404005000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1111\/j.1399-0004.1997.tb02460.x"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1997,4]]},"references-count":22,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1997,4]]}},"alternative-id":["10.1111\/j.1399-0004.1997.tb02460.x"],"URL":"https:\/\/doi.org\/10.1111\/j.1399-0004.1997.tb02460.x","archive":["Portico"],"relation":{},"ISSN":["0009-9163","1399-0004"],"issn-type":[{"value":"0009-9163","type":"print"},{"value":"1399-0004","type":"electronic"}],"subject":[],"published":{"date-parts":[[1997,4]]}}}