@article{ZwirnerAndersBohnertetal.2021,
  author    = {Zwirner, Johann and Anders, Sven and Bohnert, Simone and Burkhardt, Ralph and Da Broi, Ugo and Hammer, Niels and Pohlers, Dirk and Tse, Rexson and Ondruschka, Benjamin},
  title     = {Screening for fatal traumatic brain injuries in cerebrospinal fluid using blood-validated CK and CK-MB immunoassays},
  series = {Biomolecules},
  volume    = {11},
  journal   = {Biomolecules},
  number    = {7},
  issn      = {2218-273X},
  doi       = {10.3390/biom11071061},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-242769},
  year      = {2021},
  abstract  = {A single, specific, sensitive biochemical biomarker that can reliably diagnose a traumatic brain injury (TBI) has not yet been found, but combining different biomarkers would be the most promising approach in clinical and postmortem settings. In addition, identifying new biomarkers and developing laboratory tests can be time-consuming and economically challenging. As such, it would be efficient to use established clinical diagnostic assays for postmortem biochemistry. In this study, postmortem cerebrospinal fluid samples from 45 lethal TBI cases and 47 controls were analyzed using commercially available blood-validated assays for creatine kinase (CK) activity and its heart-type isoenzyme (CK-MB). TBI cases with a survival time of up to two hours showed an increase in both CK and CK-MB with moderate (CK-MB: AUC = 0.788, p < 0.001) to high (CK: AUC = 0.811, p < 0.001) diagnostic accuracy. This reflected the excessive increase of the brain-type CK isoenzyme (CK-BB) following a TBI. The results provide evidence that CK immunoassays can be used as an adjunct quantitative test aid in diagnosing acute TBI-related fatalities.},
  language  = {en}
}
@article{BeckerSperlichZinneretal.2020,
  author    = {Becker, Manuel and Sperlich, Billy and Zinner, Christoph and Achtzehn, Silvia},
  title     = {Intra-Individual and Seasonal Variation of Selected Biomarkers for Internal Load Monitoring in U-19 Soccer Players},
  series = {Frontiers in Physiology},
  volume    = {11},
  journal   = {Frontiers in Physiology},
  number    = {838},
  issn      = {1664-042X},
  doi       = {10.3389/fphys.2020.00838},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-209616},
  year      = {2020},
  abstract  = {The aim of this study was to investigate inter-day and -week as well as intra- and inter-individual variation of selected biomarkers in high-performance youth soccer players to assist practitioners interpreting player's internal load to counteract underperformance and unwanted health risks. Eleven male youth soccer players were tested multiple times during two 3-week periods at midpoint (3-wkmid) and at the end (3-wkend) of the first half of a German under-19 1. Bundesliga season. The levels of creatine kinase (CK), urea, and C-reactive protein (CRP) were measured during 3-wkmid and 3-wkend each Monday, Wednesday, and Friday. In 3-wkmid the CK median was 14\% higher (241 vs. 212 U/L) compared to 3-wkend (P = 0.26, ES = 0.16). Overall, the medians of CK, urea (P = 0.59, ES = 0.08), and CRP (P = 0.56, ES = 0.10) during 3-wkmid did not differ to the values of 3-wkend. Daily coefficient of variations (CVs) ranged from 22 to 71\% (CK), 17 to 37\% (urea), and 9 to 164\% (CRP). Individual medians ranged from 101 to 350 U/L (CK), 23 to 50 mg/dL (urea), and 0.6 to 1.1 mg/L (CRP). High intra-individual variability was demonstrated by large intra-individual CVs (medians: CK 50\%, urea 18\%, and CRP 45\%). Our data show (i) large inter-day and inter-week variability of all biomarkers, depending on the external load and (ii) considerable inter- and intra-individual parameter variations. Creatine kinase concentrations could sensitively reflect soccer-specific loads during the season.},
  language  = {en}
}