{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T03:40:13Z","timestamp":1777434013612,"version":"3.51.4"},"reference-count":0,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2003,1,1]],"date-time":"2003-01-01T00:00:00Z","timestamp":1041379200000},"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":[[2003,1,1]]},"abstract":"<jats:p>The oxidative phosphorylation system (OXPHOS) is organized into five multi-protein complexes, comprising four complexes (I-IV) of the respiratory chain and ATP synthase (complex V). OXPHOS has a vital role in cellular energy metabolism and ATP production. Enzyme analysis of individual OXPHOS complexes in a skeletal muscle biopsy remains the mainstay of the diagnostic process for patients suspected of mitochondrial cytopathy. Practical guidelines are presented to provide optimal conditions for performance of laboratory investigations and a reliable diagnosis. A fresh muscle biopsy is preferable to a frozen muscle sample because the overall capacity of the OXPHOS system can be measured in a fresh biopsy. In about 25% of patients referred for muscle biopsy to our centre, reduced substrate oxidation rates and ATP+creatine phosphate production rates were found without any defect in complexes I-V and the pyruvate dehydrogenase complex. Investigation of frozen muscle biopsy alone may lead to false-negative diagnoses in many patients. In some patients, it is necessary to investigate fibroblasts for prospective diagnostic purposes. An exact diagnosis of respiratory chain defects is a prerequisite for rational therapy and genetic counselling. Provided guidelines for specimen collection are followed, there are now reliable methods for identifying respiratory chain defects.<\/jats:p>","DOI":"10.1258\/000456303321016114","type":"journal-article","created":{"date-parts":[[2003,1,23]],"date-time":"2003-01-23T22:39:03Z","timestamp":1043361543000},"page":"3-8","source":"Crossref","is-referenced-by-count":57,"title":["Some practical aspects of providing a diagnostic service for respiratory chain defects"],"prefix":"10.1177","volume":"40","author":[{"given":"A.J.M.","family":"Janssen","sequence":"first","affiliation":[{"name":"Nijmegen Centre for Mitochondrial Disorders, Department of Pediatrics, University Medical Centre Nijmegen, Geert Grooteplein 10, PO Box 9101, 6500 HB Nijmegen, The\r         Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J.A.M.","family":"Smeitink","sequence":"additional","affiliation":[{"name":"Nijmegen Centre for Mitochondrial Disorders, Department of Pediatrics, University Medical Centre Nijmegen, Geert Grooteplein 10, PO Box 9101, 6500 HB Nijmegen, The\r         Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"L.P.","family":"van den Heuvel","sequence":"additional","affiliation":[{"name":"Nijmegen Centre for Mitochondrial Disorders, Department of Pediatrics, University Medical Centre Nijmegen, Geert Grooteplein 10, PO Box 9101, 6500 HB Nijmegen,\r         The Netherlands"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2003,1,1]]},"container-title":["Annals of Clinical Biochemistry: International Journal of Laboratory Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1258\/000456303321016114","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1258\/000456303321016114","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T11:52:33Z","timestamp":1777377153000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1258\/000456303321016114"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2003,1,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2003,1,1]]}},"alternative-id":["10.1258\/000456303321016114"],"URL":"https:\/\/doi.org\/10.1258\/000456303321016114","relation":{},"ISSN":["0004-5632","1758-1001"],"issn-type":[{"value":"0004-5632","type":"print"},{"value":"1758-1001","type":"electronic"}],"subject":[],"published":{"date-parts":[[2003,1,1]]}}}