{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T16:58:55Z","timestamp":1790441935338,"version":"4.1.0"},"reference-count":32,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T00:00:00Z","timestamp":1790380800000},"content-version":"vor","delay-in-days":25,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"Laboklin Laboratory for Clinical Diagnostics GmbH & Co. KG, Germany"},{"DOI":"10.13039\/501100007537","name":"Freie Universit\u00e4t Berlin","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100007537","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The accuracy of serum thymidine kinase 1 (TK1S) as a biomarker of lymphoma in horses is variable. The value of measurement in body cavity fluid (TK1F) has not been established.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Hypothesis\/Objectives<\/jats:title>\n                    <jats:p>(1) TK1F and TK1S will be higher in horses with lymphoma compared to diseased controls (DCs); (2) TK1F will be higher than TK1S; and (3) there will be a strong correlation between both measurements.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Animals<\/jats:title>\n                    <jats:p>Twenty animals in the lymphoma and 31 animals with nonneoplastic, gastrointestinal\/respiratory disorders in DC group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This was a cross-sectional study using prospectively collected data and samples obtained during routine diagnostic evaluation at referral hospitals. Thymidine kinase 1 was measured using chemiluminescence immunoassay and presented as median (and interquartile range). Nonparametric tests compared TK1F and TK1S between and within groups and Kendall\u2019s Tau assessed correlation between TK1F and TK1S.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Median TK1F was 7.48 (2.20-48.23) U\/L in horses with lymphoma vs 2.50 (0.59-4.83) U\/L in the DC group (P\u00a0=\u00a0.007); median TK1S was 4.26 (0.46-9.37) U\/L vs 0.40 (0.40-0.75) U\/L (P\u00a0&amp;lt;\u00a0.001), respectively. Both biomarkers showed good discrimination (area under the curve &amp;gt;\u20090.70) between lymphoma and the DC group, with optimal cutoff values of 5.7 and 2.5\u00a0U\/L, respectively. Thymidine kinase 1 activity in body cavity fluid (3.62 [0.85-9.86] U\/L) was significantly higher than TK1S (0.50 [0.40-2.09] U\/L; P\u00a0&amp;lt;\u00a0.001) and there was no significant correlation between them within groups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions and clinical importance<\/jats:title>\n                    <jats:p>Thymidine kinase 1 activity in body cavity fluid and TK1S provide different information and should be interpreted independently. They proved useful in lymphoma diagnosis, but not as a standalone test.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Abstract Translated to German<\/jats:title>\n                    <jats:sec>\n                      <jats:title>Hintergrund<\/jats:title>\n                      <jats:p>Die Zuverl\u00e4ssigkeit der Thymidinkinase-1-Aktivit\u00e4t im Serum (TK1S) als Lymphom-Biomarker bei Pferden ist unterschiedlich. Die Messung in K\u00f6rperh\u00f6hlenfl\u00fcssigkeit (TK1F) ist noch nicht etabliert.<\/jats:p>\n                    <\/jats:sec>\n                    <jats:sec>\n                      <jats:title>Hypothesen\/Ziele<\/jats:title>\n                      <jats:p>(1) TK1F und TK1S sind bei Pferden mit Lymphom im Vergleich zu erkrankten Kontrolltieren (DC) erh\u00f6ht; (2) TK1F ist h\u00f6her als TK1S; (3) es besteht eine starke Korrelation zwischen beiden Biomarkern.<\/jats:p>\n                    <\/jats:sec>\n                    <jats:sec>\n                      <jats:title>Tiere<\/jats:title>\n                      <jats:p>Zwanzig Tiere in der Lymphomgruppe und einsinddreissig Tiere mit verschiedenen nicht-neoplastischen gastrointestinalen\/respiratorischen Erkrankungen in der DC-Gruppe.<\/jats:p>\n                    <\/jats:sec>\n                    <jats:sec>\n                      <jats:title>Methoden<\/jats:title>\n                      <jats:p>Es handelte sich um eine Querschnittsstudie mit prospektiv erhobenen Daten und Proben, die im Rahmen der routinem\u00e4\u00dfigen diagnostischen Abkl\u00e4rung in \u00dcberweisungskliniken gewonnen wurden. TK1 wurde mittels Chemilumineszenz-Immunoassay gemessen und als Median (und Interquartilsabstand) dargestellt. Mittles nichtparametrischer Tests wurden TK1F und TK1S zwischen und innerhalb der Gruppen verglichen und Kendals Tau bewertete die Korrelation zwischen TK1F und TK1S.<\/jats:p>\n                    <\/jats:sec>\n                    <jats:sec>\n                      <jats:title>Ergebnisse<\/jats:title>\n                      <jats:p>Der Median von TK1F betrug 7,48 (2,20-48,23) U\/L bei Pferden mit Lymphom gegen\u00fcber 2,50 (0,59-4,83) U\/L in der DC-Gruppe (P\u00a0=\u00a00,007) und der Medianwert f\u00fcr TK1S betrug 4,26 (0,46-9,37) U\/L gegen\u00fcber 0,40 (0,40-0,75) U\/L (P\u00a0&amp;lt;\u00a00,001). Beide Biomarker zeigten eine gute Unterscheidungsf\u00e4higkeit (AUC &amp;gt;\u20090,70) zwischen der Lymphom- und der DC-Gruppe, mit optimalen Cut-off-Werten von 5,7\u00a0U\/L und 2,5\u00a0U\/L. TK1F (3,62 (0,85-9,86) U\/L) war signifikant h\u00f6her als TK1S (0,50 (0,40-2,09) U\/L; P\u00a0&amp;lt;\u00a00,001), und es gab keine signifikante Korrelation zwischen denen innerhalb der Gruppen.<\/jats:p>\n                    <\/jats:sec>\n                    <jats:sec>\n                      <jats:title>Schlussfolgerungen und klinische Bedeutung<\/jats:title>\n                      <jats:p>TK1F und TK1S liefern unterschiedliche Informationen und sollten separat interpretiert werden. Sie waren in der Lymphomdiagnostik hilfreich, aber nicht als alleiniger Test geeignet.<\/jats:p>\n                    <\/jats:sec>\n                  <\/jats:sec>","DOI":"10.1093\/jvimsj\/aalag207","type":"journal-article","created":{"date-parts":[[2026,9,26]],"date-time":"2026-09-26T16:22:01Z","timestamp":1790439721000},"source":"Crossref","is-referenced-by-count":0,"title":["Thymidine kinase 1 activity in serum and body cavity fluids of horses with lymphoma"],"prefix":"10.1093","volume":"40","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6972-9738","authenticated-orcid":false,"given":"Karolina","family":"Drozdzewska","sequence":"first","affiliation":[{"name":"Equine Clinic, Freie Universit\u00e4t Berlin , Berlin ,","place":["Germany"]},{"name":"Roseworthy Veterinary Hospital, School of Animal and Veterinary Sciences, Adelaide University , Roseworthy ,","place":["Australia"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophie","family":"Burde","sequence":"additional","affiliation":[{"name":"Laboklin Laboratory for Clinical Diagnostics GmbH & Co. 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