Intraindividual Neurofilament Dynamics in Serum Mark the Conversion to Sporadic Parkinson's Disease.

BACKGROUND AND OBJECTIVES: With disease-modifying treatment strategies on the horizon, stratification of individual patients at the earliest stages of Parkinson's disease (PD) is key-ideally already at clinical disease onset. Blood levels of neurofilament light chain (NfL) provide an easily accessible fluid biomarker that might allow capturing the conversion from prodromal to manifest PD. METHODS: We assessed longitudinal serum NfL levels in subjects converting from prodromal to manifest sporadic PD (converters), at-risk subjects, and matched controls (72 participants with ≈4 visits), using single-molecule array (Simoa) technique. RESULTS: While NfL levels were not increased at the prodromal stage, subjects converting to the manifest motor stage showed a significant intraindividual acceleration of the age-dependent increase of NfL levels. CONCLUSIONS: The temporal dynamics of intraindividual NfL blood levels might mark the conversion to clinically manifest PD, providing a potential stratification biomarker for individual disease onset in the advent of precision medicine for PD. © 2020 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

RNASeq_similarity_matrix: visually identify sample mix-ups in RNASeq data using a 'genomic' sequence similarity matrix.

MOTIVATION: Mistakes in linking a patient's biological samples with their phenotype data can confound RNA-Seq studies. The current method for avoiding such sample mixups is to test for inconsistencies between biological data and known phenotype data such as sex. However, in DNA studies a common QC step is to check for unexpected relatedness between samples. Here, we extend this method to RNA-Seq, which allows the detection of duplicated samples without relying on identifying inconsistencies with phenotype data. SUMMARY: We present RNASeq_similarity_matrix: an automated tool to generate a sequence similarity matrix from RNA-Seq data, which can be used to visually identify sample mix-ups. This is particularly useful when a study contains multiple samples from the same individual, but can also detect contamination in studies with only one sample per individual. AVAILABILITY: RNASeq_similarity_matrix has been made available as a documented GPL licensed Docker image on www.github.com/nicokist/RNASeq_similarity_matrix. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Evolutions in both co-payment and generic market share for common medication in the Belgian reference pricing system.

BACKGROUND: In Belgium, a co-insurance system is applied in which patients pay a portion of the cost for medicines, called co-payment. Co-payment is intended to make pharmaceutical consumers more responsible, increase solidarity, and avoid or reduce moral hazards. OBJECTIVE: Our objective was to study the possible influence of co-payment on sales volume and generic market share in two commonly used medicine groups: cholesterol-lowering medication [statins (HMG-CoA reductase inhibitors) and fibrates] and acid-blocking agents (proton pump inhibitors and histamine H2 receptor antagonists). METHODS AND DATA: The data were extracted from the Pharmanet database, which covers pharmaceutical consumption in all Belgian ambulatory pharmacies. First, the proportion of sales volume and costs of generic products were modelled over time for the two medicine groups. Second, we investigated the relation between co-payment and contribution by the national insurance agency using change-point linear mixed models. RESULTS: The change-point analysis suggested several influential events. First, the generic market share in total sales volume was negatively influenced by the abolishment of the distinction in the maximum co-payment level for name brands and generics in 2001. Second, relaxation of the reimbursement conditions for generic omeprazole stimulated generic sales volume in 2004. Finally, an increase in co-payment for generic omeprazole was associated with a significant decrease in omeprazole sales volume in 2005. The observational analysis demonstrated several changes over time. First, the co-payment amounts for name-brand and generic drugs converged in the observed time period for both medicine groups under study. Second, the proportion of co-payment for the total cost of simvastatin and omeprazole increased over time for small packages, and more so for generic than for name-brand products. For omeprazole, both the proportion and the amount of co-payment increased over time. Third, over time the prescription of small packages shifted to an emphasis on larger packages. CONCLUSIONS: As maximum co-payment levels decreased over time, they overruled the reference pricing system in Belgium. The changes in co-payment share over time also significantly affected sales volume, but whether physicians or patients are the decisive actors on the demand side of pharmaceutical consumption remains unclear.

Conservation of HHV-6 DNA polymerase processivity factor sequence and predicted structure suggests it as a target for antiviral development.

The replication of human herpesvirus-6 (HHV-6) DNA is catalyzed by the viral DNA polymerase pU38 and the processivity factor pU27 which stabilizes the enzyme on the DNA template. The genetic polymorphism of pU27 among 46 clinical strains of HHV-6 variant A or B and four strains resistant to antivirals was investigated. Overall, 28 amino acid changes (7.6%) and a two-amino acid deletion were identified among the 368 residues of pU27, when using the U1102 (variant A) sequence as the reference. Eleven amino acid changes (3.0%) specifically differentiated both variants. The median intravariant amino acid variability was 1.2% and 0.3% for A and B, respectively. Except for a single change, the pU27 sequence of multi-drug resistant HHV-6 strains was also conserved. Structural models of pU27 for variants A and B were derived from that of the human cytomegalovirus homologue pUL44, and showed either identical or very similar residues in the regions interacting with viral DNA polymerase and viral DNA molecule. As pU27 is both highly conserved and essential for viral replication, it might constitute an interesting target for antiviral chemotherapy.