TY - JOUR A1 - Morgner, Frank A1 - Stufler, Stefan A1 - Geissler, Daniel A1 - Medintz, Igor L. A1 - Algar, W. Russ A1 - Susumu, Kimihiro A1 - Stewart, Michael H. A1 - Blanco-Canosa, Juan B. A1 - Dawson, Philip E. A1 - Hildebrandt, Niko T1 - Terbium to quantum dot FRET Bioconjugates for clinical diagnostics influence of human plasma on optical and assembly properties JF - Sensors N2 - Forster resonance energy transfer (FRET) from luminescent terbium complexes (LTC) as donors to semiconductor quantum dots (QDs) as acceptors allows extraordinary large FRET efficiencies due to the long Forster distances afforded. Moreover, time-gated detection permits an efficient suppression of autofluorescent background leading to sub-picomolar detection limits even within multiplexed detection formats. These characteristics make FRET-systems with LTC and QDs excellent candidates for clinical diagnostics. So far, such proofs of principle for highly sensitive multiplexed biosensing have only been performed under optimized buffer conditions and interactions between real-life clinical media such as human serum or plasma and LTC-QD-FRET-systems have not yet been taken into account. Here we present an extensive spectroscopic analysis of absorption, excitation and emission spectra along with the luminescence decay times of both the single components as well as the assembled FRET-systems in TRIS-buffer, TRIS-buffer with 2% bovine serum albumin, and fresh human plasma. Moreover, we evaluated homogeneous LTC-QD FRET assays in QD conjugates assembled with either the well-known, specific biotin-streptavidin biological interaction or, alternatively, the metal-affinity coordination of histidine to zinc. In the case of conjugates assembled with biotin-streptavidin no significant interference with the optical and binding properties occurs whereas the histidine-zinc system appears to be affected by human plasma. KW - FRET KW - quantum dots KW - terbium KW - luminescence lifetime KW - blood KW - plasma KW - clinical diagnostics KW - biotin KW - streptavidin KW - histidin KW - immunoassay Y1 - 2011 U6 - https://doi.org/10.3390/s111009667 SN - 1424-8220 VL - 11 IS - 10 SP - 9667 EP - 9684 PB - MDPI CY - Basel ER - TY - JOUR A1 - Kuhl, Juliane A1 - Aurich, Jörg E. A1 - Wulf, Manuela A1 - Hurtienne, A. A1 - Schweigert, Florian J. A1 - Aurich, Christine T1 - Effects of oral supplementation with beta-carotene on concentrations of beta-carotene, vitamin A and alpha-tocopherol in plasma, colostrum and milk of mares and plasma of their foals and on fertility in mares JF - Journal of animal physiology and animal nutrition N2 - In this study, effects of oral beta-carotene supplementation to mares (beta-carotene group: 1000 mg/day, n = 15; control group: n = 15) from 2 weeks before foaling until 6 weeks thereafter on concentrations of beta-carotene, vitamin A and a-tocopherol in plasma, colostrum and milk and plasma of their foals were determined. In addition, effects on fertility were studied. Beta-carotene concentrations increased in plasma and colostrum of beta-carotene-supplemented mares compared to control mares (p < 0.05). In mares of both groups, beta-carotene concentrations were higher in colostrum than in milk (p < 0.05). In foals, beta-carotene concentrations increased with colostrum uptake and were higher in foals born to supplemented mares (p < 0.05; control group: 0.0003 +/- 0.0002 mu g/ml on day 0, 0.008 +/- 0.0023 mu g/ml on day 1; beta-carotene group: 0.0005 +/- 0.0003 mu g/ml on day 0, 0.048 +/- 0.018 mu g/ml on day 1). Concentrations of vitamin A and a-tocopherol were higher in colostrum than in milk (p < 0.05) but did not differ between groups. Concentration of a-tocopherol in plasma of mares decreased over time and in foals, increased markedly within 4 days after birth. All but one mare (control group) showed oestrus within 2 weeks post-partum. Occurrence of oestrus did not differ between groups. More mares of the control group (7/7 vs. 5/12 in the beta-carotene group) became pregnant after being bred in first post-partum oestrus (p < 0.05). In conclusion, beta-carotene supplementation to mares increased beta-carotene concentrations in plasma, colostrum and milk of mares and plasma of their foals but had no positive effects on fertility. KW - carotene KW - colostrum KW - foal KW - mare KW - plasma KW - a-tocopherol KW - vitamin A Y1 - 2012 U6 - https://doi.org/10.1111/j.1439-0396.2011.01150.x SN - 0931-2439 VL - 96 IS - 3 SP - 376 EP - 384 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Mueller, K. A1 - Raila, Jens A1 - Altenkamp, Rainer A1 - Schmidt, D. A1 - Dietrich, R. A1 - Hurtienne, Andrea A1 - Wink, M. A1 - Krone, O. A1 - Brunnberg, Leo A1 - Schweigert, Florian J. T1 - Concentrations of retinol, 3,4-didehydroretinol, and retinyl esters in plasma of free-ranging birds of prey JF - Journal of animal physiology and animal nutrition N2 - This study investigated vitamin A compounds in the plasma of healthy free-ranging Central European raptors with different feeding strategies. Plasma samples of nestlings of white-tailed sea eagle [white-tailed sea eagle (WTSE), Haliaeetus albicilla) (n = 32), osprey (Pandion haliaetus) (n = 39), northern goshawk (Accipiter gentilis) (n = 25), common buzzard (Buteo buteo) (n = 31), and honey buzzard (Pernis apivorus) (n = 18) and adults of WTSE (n = 10), osprey (n = 31), and northern goshawk (n = 45) were investigated with reversed-phase-high-performance liquid chromatography (RP-HPLC). In WTSE, northern goshawks and common buzzards retinol were the main plasma component of vitamin A, whilst in ospreys and honey buzzards, 3,4-didehydroretinol predominated. The median of the retinol plasma concentration in the nestlings group ranged from 0.12 to 3.80 mu M and in the adult group from 0.15 to 6.13 mu M. Median plasma concentrations of 3,4-didehydroretinol in nestlings ranged from 0.06 to 3.55 mu M. In adults, northern goshawks had the lowest plasma concentration of 3,4-didehydroretinol followed by WTSE and ospreys. The plasma of all investigated species contained retinyl esters (palmitate, oleate, and stearate). The results show considerable species-specific differences in the vitamin A plasma concentrations that might be caused by different nutrition strategies. KW - birds of prey KW - plasma KW - retinol KW - 3,4-didehydroretinol KW - retinyl esters Y1 - 2012 U6 - https://doi.org/10.1111/j.1439-0396.2011.01219.x SN - 0931-2439 VL - 96 IS - 6 SP - 1044 EP - 1053 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Stoessel, Daniel A1 - Schulte, Claudia A1 - dos Santos, Marcia C. Teixeira A1 - Scheller, Dieter A1 - Rebollo-Mesa, Irene A1 - Deuschle, Christian A1 - Walther, Dirk A1 - Schauer, Nicolas A1 - Berg, Daniela A1 - da Costa, Andre Nogueira A1 - Maetzler, Walter T1 - Promising Metabolite Profiles in the Plasma and CSF of Early Clinical JF - Frontiers in Aging Neuroscience N2 - Parkinson's disease (PD) shows high heterogeneity with regard to the underlying molecular pathogenesis involving multiple pathways and mechanisms. Diagnosis is still challenging and rests entirely on clinical features. Thus, there is an urgent need for robust diagnostic biofluid markers. Untargeted metabolomics allows establishing low-molecular compound biomarkers in a wide range of complex diseases by the measurement of various molecular classes in biofluids such as blood plasma, serum, and cerebrospinal fluid (CSF). Here, we applied untargeted high-resolution mass spectrometry to determine plasma and CSF metabolite profiles. We semiquantitatively determined small-molecule levels (<= 1.5 kDa) in the plasma and CSF from early PD patients (disease duration 0-4 years; n = 80 and 40, respectively), and sex-and age-matched controls (n = 76 and 38, respectively). We performed statistical analyses utilizing partial least square and random forest analysis with a 70/30 training and testing split approach, leading to the identification of 20 promising plasma and 14 CSF metabolites. The semetabolites differentiated the test set with an AUC of 0.8 (plasma) and 0.9 (CSF). Characteristics of the metabolites indicate perturbations in the glycerophospholipid, sphingolipid, and amino acid metabolism in PD, which underscores the high power of metabolomic approaches. Further studies will enable to develop a potential metabolite-based biomarker panel specific for PD KW - biomarker KW - untargeted metabolomics KW - neurodegeneration KW - plasma KW - CSF KW - machinelearning Y1 - 2018 U6 - https://doi.org/10.3389/fnagi.2018.00051 SN - 1663-4365 VL - 10 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Weber, Daniela A1 - Kochlik, Bastian A1 - Demuth, Ilja A1 - Steinhagen-Thiessen, Elisabeth A1 - Grune, Tilman A1 - Norman, Kristina T1 - Plasma carotenoids, tocopherols and retinol BT - Association with age in the Berlin Aging Study II JF - Redox Biology N2 - Regular consumption of fruits and vegetables, which is related to high plasma levels of lipid-soluble micro-nutrients such as carotenoids and tocopherols, is linked to lower incidences of various age-related diseases. Differences in lipid-soluble micronutrient blood concentrations seem to be associated with age. Our retrospective analysis included men and women aged 22-37 and 60-85 years from the Berlin Aging Study II. Participants with simultaneously available plasma samples and dietary data were included (n = 1973). Differences between young and old groups were found for plasma lycopene, alpha-carotene, alpha-tocopherol, beta-cryptoxanthin (only in women), and gamma-tocopherol (only in men). beta-Carotene, retinol and lutein/zeaxanthin did not differ between young and old participants regardless of the sex. We found significant associations for lycopene, alpha-carotene (both inverse), alpha-tocopherol, gamma-tocopherol, and beta-carotene (all positive) with age. Adjusting for BMI, smoking status, season, cholesterol and dietary intake confirmed these associations, except for beta-carotene. These micronutrients are important antioxidants and associated with lower incidence of age-related diseases, therefore it is important to understand the underlying mechanisms in order to implement dietary strategies for the prevention of age-related diseases. To explain the lower lycopene and alpha-carotene concentration in older subjects, bioavailability studies in older participants are necessary. KW - carotenoids KW - tocopherols KW - micronutrients KW - age KW - plasma KW - food frequency questionnaire Y1 - 2020 U6 - https://doi.org/10.1016/j.redox.2020.101461 SN - 2213-2317 VL - 32 SP - 1 EP - 8 PB - Elsevier CY - Amsterdam ER -