[Benefits of participatory involvement of patients in the development of a dermatological treatment app-A report from the practice]. / Nutzen der partizipatorischen Mitwirkung von PatientInnen an der Entwicklung einer dermatologischen Therapie-App ­ ein Bericht aus der Praxis.

Approximately 2% of the German population suffer from psoriasis. HybridVITA has developed a mobile application (app) that enables psoriasis patients to independently document the progression of the disease and the current psychological stress at home. The HybridVITA app was created in close collaboration with user groups to ensure optimal adaptation to their needs. Two interactive workshops were held with the user groups and the technical developers of the app as a core element of the developmental process. The workshops identified the needs and suggestions for improvement of the various user groups and formulated user stories for the further development of the app using the Scrum method. The participatory approach of the workshop enabled the project team to gather valuable practical knowledge at an early stage of development. The team's awareness of potential obstacles during the early stages of the project enabled them to proactively identify and address these issues prior to implementing the app in dermatological care. We are confident that a patient-centered and participatory approach to health app development can provide valuable insights for developers.

Resemblance-Ranking Peptide Library to Screen for Binders to Antibodies on a Peptidomic Scale.

A novel resemblance-ranking peptide library with 160,000 10-meric peptides was designed to search for selective binders to antibodies. The resemblance-ranking principle enabled the selection of sequences that are most similar to the human peptidome. The library was synthesized with ultra-high-density peptide arrays. As proof of principle, screens for selective binders were performed for the therapeutic anti-CD20 antibody rituximab. Several features in the amino acid composition of antibody-binding peptides were identified. The selective affinity of rituximab increased with an increase in the number of hydrophobic amino acids in a peptide, mainly tryptophan and phenylalanine, while a total charge of the peptide remained relatively small. Peptides with a higher affinity exhibited a lower sum helix propensity. For the 30 strongest peptide binders, a substitutional analysis was performed to determine dissociation constants and the invariant amino acids for binding to rituximab. The strongest selective peptides had a dissociation constant in the hundreds of the nano-molar range. The substitutional analysis revealed a specific hydrophobic epitope for rituximab. To show that conformational binders can, in principle, be detected in array format, cyclic peptide substitutions that are similar to the target of rituximab were investigated. Since the specific binders selected via the resemblance-ranking peptide library were based on the hydrophobic interactions that are widespread in the world of biomolecules, the library can be used to screen for potential linear epitopes that may provide information about the cross-reactivity of antibodies.

Vitamin D status and cancer prevalence of hemodialysis patients in Germany.

AIM: To describe Vitamin D (VitD) status and prevalence of cancer in a large cohort of ambulatory hemodialysis patients in Germany. PATIENTS AND METHODS: In a registry study adult patients starting dialysis between 2006 and 2012 were analyzed for VitD blood levels and International classification of diseases (ICD)-10 cancer diagnoses. RESULTS: Almost one third (32.7%) of patients initiating dialysis, had VitD levels<12.5 ng/ml and 79.7% had levels<30 ng/ml (n=8,377). Average VitD at dialysis initiation increased from 18.0 to 23.2 ng/ml between 2006 and 2012. Prevalence of cancer in this cohort was 22.1% with genital, renal and gastro-intestinal cancers being most common. Cancer frequencies were similar in patients with high and low vitamin D levels. CONCLUSION: Most chronic hemodialysis patients were vitamin D-deficient in spite of concurrent vitamin D supplementation. The burden of cancer was high in these patients. Future studies should address the role of vitamin D treatment on the course and progression of cancer in chronic kidney disease (CKD) patients.