The acceptance of the K‐SADS‐PL – potential predictors for the overall satisfaction of parents and interviewers

The presented study investigated the interviewee (parents) and interviewer acceptance of the semi‐structured diagnostic interview Kiddie Schedule for Affective Disorders and Schizophrenia for School Aged Children Present Lifetime version (KSADS‐PL; German version). Seventeen certified interviewers conducted 231 interviews (interviewers conducted several interviews; interviewees were only questioned once). Interviewees and interviewers anonymously rated their acceptance right after the interview was finished. The nested data structure was analysed regarding an individual interviewer bias and potential predictors of overall satisfaction. Therefore, factors improvable by interviewer training were included, as well as fixed factors which cannot be improved by professional training. The overall satisfaction was evaluated as highly positive with significant higher interviewee and interviewer ratings in the research as compared to the clinical recruitment setting. An individual bias of the interviewer on his or her own acceptance over time, but not on the evaluation of the corresponding interviewee was found. Neither the professional background nor the gender of the interviewer had a significant contribution in predicting these differences. The interviewer model showed no significant change over time and only the interview duration and the interviewee acceptance were significant predictors for interviewer overall satisfaction. Regarding the interviewee model, just the interviewer acceptance was a significant predictor. Copyright Copyright © 2015 John Wiley & Sons, Ltd.     

F-FECNT: Validation as PET dopamine transporter ligand in parkinsonism

The positron emission tomography (PET) tracer 2β-carbomethoxy-3β-(4-chlorophenyl)-8-(2-[18F]-fluoroethyl)-nortropane (¹⁸F-FECNT) is a highly specific ligand for dopamine transporter (DAT) that yields higher peak striatum-to-cerebellum ratios and offers more favorable kinetics than most ¹⁸F-radiolabeled DAT ligands currently available. The goal of this study is to validate the use of ¹⁸F-FECNT as a PET radiotracer to assess the degree of striatal dopamine terminals denervation and midbrain dopaminergic cell loss in MPTP-treated parkinsonian monkeys. Three rhesus monkeys received weekly injections of MPTP (0.2–0.5 mg/kg) for 21 weeks, which resulted in the progressive development of a moderate level of parkinsonism. We carried out ¹⁸F-FECNT PET at baseline (twice; 10 weeks apart) and at week 21 post-MPTP injections. Postmortem stereological cell counts of dopaminergic neurons in the ventral midbrain, and intensity measurements of DAT and tyrosine hydroxylase (TH) immunoreactivity in the striatum were performed and correlated with striatal and ventral midbrain PET data. Three additional monkeys were used as controls for midbrain dopaminergic cell counts, and striatal DAT or TH immunoreactivity measurements. The correlation and coefficient of variance between ¹⁸F-FECNT test–retest specific uptake ratios were 0.99 (R²) and 2.65%, respectively. The ¹⁸F-FECNT binding potential of the ventral midbrain and striatal regions was tightly correlated with postmortem stereological cell counts of nigral dopaminergic neurons (R² = 0.91), and striatal DAT (R² = 0.83) or TH (R² = 0.88) immunoreactivity intensity measurements. These findings demonstrate that ¹⁸F-FECNT is a highly sensitive PET imaging ligand to quantify both striatal dopamine denervation and midbrain dopaminergic cell loss associated with parkinsonism.