Joint recommendations on cost calculation and estimation in paediatric clinical trials.

The conduct of clinical trials in paediatrics is essential to improve drug therapy in children. In Europe, paediatric clinical trials have been supported by the European Paediatric Regulation since 2007, but there is still a great need for high-quality clinical trials. The personnel and time required to conduct clinical trials in accordance with EU Regulations 536/2014 and 745/2017 is considerably higher compared to other studies, such as observational studies. It is important that this additional workload for the trial centre is fully compensated, also taking into account EU state aid rules. In paediatric trials, it is necessary to take into account the special requirements of paediatric and adolescent medicine when calculating the additional costs. Within the framework of the pan-European paediatric study network c4c/GermanNetPaeT, a working group dealt with specific aspects of cost calculation in order to support paediatric study centres in internal cost calculation as well as in the subsequent preparation of financing requirements for industrial sponsors or public funders. In several workshops the working group developed a cost calculation template with the content derived from the "Joint recommendations for a total services account as a factor in simplifying contracts" of the Deutsche Hochschulmedizin (DHM, German University Medicine), the Netzwerk der Koordinierungszentren für Klinische Studien (KKS Network, Network of Coordinating Centres for Clinical Trials) and the Verband Forschender Arzneimittelhersteller (vfa, German Association of Research-Based Pharmaceutical Companies). By estimating the specific time required for measures and investigations as part of a sample study, the background to the increased time required was discussed and a list with aspects to be considered for cost calculation was compiled together with the study centres. The paediatrics-specific aspects mentioned in detail are intended to increase understanding of the particular problem of higher costs for clinical trials involving children and adolescents and the need for correspondingly appropriate remuneration. This transparent and comprehensible presentation of the higher financial requirements for both the study centres and the financial supporters is intended to promote the high-quality conduct of clinical trials in paediatric study centres in the long term.

Stem cells in middle ear cholesteatoma contribute to its pathogenesis.

Cholesteatoma is a potentially life-threatening middle ear lesion due to the formation of an inflamed ectopic mass of keratinizing squamous epithelium. Surgical removal remains the only treatment option, emphasizing the need to gain a better understanding of this severe disease. We show for the first time that stem cells residing in cholesteatoma tissue contribute to disease progression. Cells expressing the "stemness" markers Nestin and S100B were detected in middle ear cholesteatoma and auditory canal skin. Isolated Nestin + /S100B + -cells showed the capability for self-renewal, neurosphere formation and differentiation into mesodermal and ectodermal cell types. Compared to auditory canal skin stem cells middle ear cholesteatoma-derived stem cells displayed an enhanced susceptibility to inflammatory stimuli, and this suggested a possible contribution to the inflammatory environment in cholesteatoma tissue. Cholesteatoma derived stem cells were able to differentiate into keratinocyte-like cells using factors mimicking the microenvironment of cholesteatoma. Our findings demonstrate a new perspective on the pathogenesis of cholesteatoma and may lead to new treatment strategies for this severe middle ear lesion.

Fascin controls neuronal class-specific dendrite arbor morphology.

The branched morphology of dendrites represents a functional hallmark of distinct neuronal types. Nonetheless, how diverse neuronal class-specific dendrite branches are generated is not understood. We investigated specific classes of sensory neurons of Drosophila larvae to address the fundamental mechanisms underlying the formation of distinct branch types. We addressed the function of fascin, a conserved actin-bundling protein involved in filopodium formation, in class III and class IV sensory neurons. We found that the terminal branchlets of different classes of neurons have distinctive dynamics and are formed on the basis of molecularly separable mechanisms; in particular, class III neurons require fascin for terminal branching whereas class IV neurons do not. In class III neurons, fascin controls the formation and dynamics of terminal branchlets. Previous studies have shown that transcription factor combinations define dendrite patterns; we find that fascin represents a downstream component of such programs, as it is a major effector of the transcription factor Cut in defining class III-specific dendrite morphology. Furthermore, fascin defines the morphological distinction between class III and class IV neurons. In fact, loss of fascin function leads to a partial conversion of class III neurons to class IV characteristics, while the reverse effect is obtained by fascin overexpression in class IV neurons. We propose that dedicated molecular mechanisms underlie the formation and dynamics of distinct dendrite branch types to elicit the accurate establishment of neuronal circuits.

Microarray-based identification of age-dependent differences in gene expression of human dermal fibroblasts.

Senescence is thought to play an important role in the progressive age-related decline in tissue integrity and concomitant diseases, but not much is known about the complex interplay between upstream regulators and downstream effectors. We profiled whole genome gene expression of non-stressed and rotenone-stressed human fibroblast strains from young and oldest old subjects, and measured senescence associated ß-gal activity. Microarray results identified gene sets involved in carbohydrate metabolism, Wnt/ß-catenin signaling, the cell cycle, glutamate signaling, RNA-processing and mitochondrial function as being differentially regulated with chronological age. The most significantly differentially regulated mRNA corresponded to the p16 gene. p16 was then investigated using qPCR, Western blotting and immunocytochemistry. In conclusion, we have identified cellular pathways that are differentially expressed between fibroblast strains from young and old subjects.