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Advanced in vitro systems such as multicellular spheroids and lab-on-a-chip devices have been developed, but often fall short in reproducing the tissue scale and self-organization of human diseases. A bioprinted artificial tumor model is introduced with endothelial and stromal cells self-organizing into perfusable and functional vascular structures. This model uses 3D hydrogel matrices to embed multicellular tumor spheroids, allowing them to grow to mesoscopic scales and to interact with endothelial cells. It is shown that angiogenic multicellular tumor spheroids promote the growth of a vascular network, which in turn further enhances the growth of cocultivated tumor spheroids. The self-developed vascular structure infiltrates the tumor spheroids, forms functional connections with the bioprinted endothelium, and can be perfused by erythrocytes and polystyrene microspheres. Moreover, cancer cells migrate spontaneously from the tumor spheroid through the self-assembled vascular network into the fluid flow. Additionally, tumor type specific characteristics of desmoplasia, angiogenesis, and metastatic propensity are preserved between patient-derived samples and tumors derived from this same material growing in the bioreactors. Overall, this modular approach opens up new avenues for studying tumor pathophysiology and cellular interactions in vitro, providing a platform for advanced drug testing while reducing the need for in vivo experimentation., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Background and Purpose: Identification of ischemic stroke patients at high risk of developing life-threatening malignant infarction at an early stage is critical to consider more rigorous monitoring and further therapeutic measures. We hypothesized that a score consisting of simple measurements of visually evident ischemic changes in non-enhanced CT (NEMMI score) predicts malignant middle cerebral artery (MCA) infarctions (MMI) with similar diagnostic power compared to other baseline clinical and imaging parameters. Methods: One hundred and nine patients with acute proximal MCA occlusion were included. Fifteen (13.8%) patients developed MMI. NEMMI score was defined using the sum of the maximum diameter (anterior-posterior plus medio-lateral) of the hypoattenuated lesion in baseline-CT multiplied by a hypoattenuation factor (3-point visual grading in non-enhanced CT, no/subtle/clear hypoattenuation = 1/2/3). Receiver operating characteristic (ROC) curve analysis and multivariable logistic regression analysis were used to calculate the predictive values of the NEMMI score, baseline clinical and other imaging parameters. Results: The median NEMMI score at baseline was 13.6 (IQR: 11.6-31.1) for MMI patients, and 7.7 (IQR: 3.9-11.2) for patients with non-malignant infarctions ( p < 0.0001). Based on ROC curve analysis, a NEMMI score >10.5 identified MMI with good discriminative power (AUC: 0.84, sensitivity/specificity: 93.3/70.7%), which was higher compared to age (AUC: 0.76), NIHSS (AUC: 0.61), or ischemic core volume (AUC: 0.80). In multivariable logistic regression analysis, NEMMI score was significantly and independently associated with MMI (OR: 1.33, 95%CI: 1.13-1.56, p < 0.001), adjusted for recanalization status. Conclusion: The NEMMI score is a quick and simple rating tool of early ischemic changes on CT and could serve as an important surrogate marker for developing malignant edema. Its diagnostic accuracy was similar to CTP and clinical parameters., Competing Interests: JF receives research support from EU, BMBF, BMWi, DFG, Acandis, Medtronic, Microvention, Stryker. He is consultant for Acandis, Codman, Cerenovus, Medtronic, Microvention, Penumbra, Phenox, and Stryker, holds Stock of Tegus Medical and has executive functions at Eppdata (all unrelated). The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Bechstein, Meyer, Breuel, Faizy, Hanning, van Horn, McDonough, Fiehler and Broocks.)

Manipulation of pre-mRNA processing is a promising approach toward overcoming disease-causing mutations and treating human diseases. We show that a combined treatment applying two splice-manipulating technologies improves therapeutic efficacies to correct mutation-induced splice defects. Previously, we identified a family affected by retinitis pigmentosa caused by the homozygous BBS1 splice donor site mutation c.479G > A. The mutation leads to both exon 5 skipping and intron 5 retention. We developed a therapeutic approach applying lentivirus-mediated gene delivery of engineered U1 small nuclear RNA (U1), which resulted in increased levels of correctly spliced BBS1. Herein, we show that the therapeutic effect of the engineered U1 efficiently reverted exon skipping but failed to reduce the intron retention. To complement the engineered U1 treatment, we identified four different antisense oligonucleotides (AONs) that block intron 5 retention in BBS1 transcripts. A treatment using engineered U1 in combination with AONs showed the highest therapeutic efficacy and increased the amount of correctly spliced BBS1 transcripts. We did not detect elevated levels of apoptotic cell death in AON-treated cell lines. In conclusion, engineered U1 or AONs provide efficient therapies with complementary effects and can be combined to increase efficacy of therapeutic approaches to correct splice defects., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

The neurons in the mammalian and avian auditory hindbrain nuclei share a number of significant morphological and physiological properties for fast, secure and precise neurotransmission, such as giant synapses, voltage-gated K+ channels and fast AMPA receptors. Based on the independent evolution of the middle ear in these two vertebrate lineages, on different embryonic origins of the nuclei and on marked differences on the circuit level, these similarities are assumed to reflect convergent evolution. Independent acquisition of similar phenotypes can be produced by divergent evolution of genetic mechanisms or by similar molecular mechanisms. The distinction between these two possibilities requires knowledge of the gene regulatory networks (GRNs) that orchestrate the development of auditory hindbrain structures. We therefore compared the expression pattern of GRN components, both transcription factors (TFs) and noncoding RNA, during terminal differentiation of the auditory hindbrain structures in mouse and chicken when neurons acquire their final morphological and electrophysiological properties. In general, we observed broad expression of these genes in the mouse auditory cochlear nucleus complex and the superior olivary complex at both postnatal day 4 (P4) and at P25, and for the chicken at the equivalent developmental stages, i.e. embryonic day 13 (E13) and at P14-P17. Our data are in agreement with a model based on similar molecular mechanisms underlying terminal differentiation and maintenance of neuronal cell identity in the auditory hindbrain of different vertebrate lineages. This conservation might reflect developmental constraints arising from the tagmatic organization of rhombomeres and the evolutionarily highly conserved GRNs operating in these structures., (© 2016 S. Karger AG, Basel.)