Brokerage in urban networks on diversity and inclusion: The case of Rotterdam

Urban governance research posits a trend towards more cooperation between state and non-state actors. We also know that civil society organizations working on common issues often reinforce each other to secure a stronger voice. However, little research so far brings together urban governance and civil society coordination. This is particularly interesting for the action and policy field of diversity and inclusion, given its constant flux, multi-dimensionality, and political salience, as well as the many competing actors and agendas. Based on an in-depth case study of the city of Rotterdam, this article investigates the relations among organizations that focus on the interests of migrants and other marginalized residents and between these organizations and the municipality. We use qualitative and quantitative Social Network Analysis and draw on 27 semi-structured qualitative interviews as well as 25 network maps carried out with and drawn by representatives of civil society organizations. Our findings show a stratified governance network of actors working on diversity and inclusion in Rotterdam, where only a few large organizations serve as brokers, facilitating exchange but sometimes also reinforcing existing power relations. These findings underscore the importance of critically reviewing the collaborative character of urban governance in practice

Positive impact of IGF-1-coupled nanoparticles on the differentiation potential of human chondrocytes cultured on collagen scaffolds

Juliane Pasold,1 Kathleen Zander,1 Benjamin Heskamp,1 Cordula Grüttner,2 Frank Lüthen,3 Thomas Tischer,1 Anika Jonitz-Heincke,1 Rainer Bader1 1Department of Orthopaedics, Biomechanics and Implant Technology Laboratory, University Medicine Rostock, Rostock, Germany; 2Micromod Particletechnology GmbH, Rostock, Germany; 3Institute of Cell Biology, University Medicine Rostock, Rostock, Germany Purpose: In the present study, silica nanoparticles (sNP) coupled with insulin-like growth factor 1 (IGF-1) were loaded on a collagen-based scaffold intended for cartilage repair, and the influence on the viability, proliferation, and differentiation potential of human primary articular chondrocytes was examined. Methods: Human chondrocytes were isolated from the hyaline cartilage of patients (n=4, female, mean age: 73±5.1 years) undergoing primary total knee joint replacement. Cells were dedifferentiated and then cultivated on a bioresorbable collagen matrix supplemented with fluorescent sNP coupled with IGF-1 (sNP–IGF-1). After 3, 7, and 14 days of cultivation, cell viability and integrity into the collagen scaffold as well as metabolic cell activity and synthesis rate of matrix proteins (collagen type I and II) were analyzed. Results: The number of vital cells increased over 14 days of cultivation, and the cells were able to infiltrate the collagen matrix (up to 120 µm by day 7). Chondrocytes cultured on the collagen scaffold supplemented with sNP–IGF-1 showed an increase in metabolic activity (5.98-fold), and reduced collagen type I (1.58-fold), but significantly increased collagen type II expression levels (1.53-fold; P=0.02) after 7 days of cultivation compared to 3 days. In contrast, chondrocytes grown in a monolayer on plastic supplemented with sNP-IGF-1 had significantly lower metabolic activity (1.32-fold; P=0.007), a consistent amount of collagen type I, and significantly reduced collagen type II protein expression (1.86-fold; P=0.001) after 7 days compared to 3 days. Conclusion: Collagen-based scaffolds enriched with growth factors, such as IGF-1 coupled to nanoparticles, represent an improved therapeutic intervention for the targeted and controlled treatment of articular cartilage lesions. Keywords: chondrogenic differentiation, silica nanoparticles, growth factor, 3D-matrix, cartilage repai