A shedding analysis after AAV8 CNS injection revealed fragmented viral DNA without evidence of functional AAV particles in mice.

Adeno-associated viruses (AAV) are commonly used in the scientific field due to their diverse application range. However, AAV shedding, the release of virions from the host organism, can impact the safety of AAV-based approaches. An increasing number of authorities require the characterization of vector shedding in clinical trials. Recently, shedding of transduced laboratory animals has also gained attention regarding the necessary disposal measures of their waste products. However, no explicit international regulations for AAV-shedding waste exist. Generating insights into shedding dynamics becomes increasingly relevant to help authorities develop adequate regulations. To date, knowledge of AAV vector shedding in mice is very limited. Moreover, confirmation of functional shed AAV particles in mice is missing. Therefore, we examined feces, urine, and saliva of mice after CNS injection with AAV2/8. It revealed the presence of viral DNA fragments via qPCR for up to 4 days after injection. To examine AAV functionality we performed nested PCR and could not detect full-length viral genomes in any but two collected feces samples. Furthermore, a functional infection assay did not reveal evidence of intact AAV particles. Our findings are supposed to contribute murine shedding data as a foundation to help establish still lacking adequate biosafety regulations in the context of AAV shedding.

Who learns more: the impact of dual-player and single-player modes in a serious game on dental students' factual knowledge.

BACKGROUND: The use of serious games in medical education provides a bridge between rapidly developing technology and traditional health-care teaching. Building on a promising web-based serious game for reviewing and acquiring factual knowledge in dental education, the present study investigated the benefits of a dual-player mode and various game options for enhancing knowledge gain and study motivation. METHODS: Before the intervention, students' dental knowledge and game experience were assessed using a pre-knowledge test and questionnaire-based self-assessment. Students in the clinical study phase (n = 57) were stratified based on prior knowledge and gender and then randomly assigned to two groups, with two player modes: single player (SP) and dual player (DP). In the SP group, each participant played alone, whereas in the DP group, the participants played against a previously determined peer. For a period of 4 weeks, the students were able to playfully acquire knowledge from the field of operative dentistry using METIS, a serious game application with three different game options (Marathon, Sprint, and Time). After the intervention phase, both groups completed a post-knowledge test. The usability of the serious game was evaluated with a self-assessment questionnaire. RESULTS: The competitive game mode (DP mode; M = 8.92, SD = 1.85) resulted in an increase in the factual knowledge test that was a mean of 2.49 points higher than the SP mode (M = 5.89, SD = 2.19; p < 0.001). The DP group also found the game significantly more helpful for learning (p = 0.04) and engaged more with the teaching content because of the app (p = 0.04). Overall, the usability of METIS was rated as excellent, and students successfully improved their knowledge of dentistry after game play with both game modes (SP, DP, p < 0.001), with the game option "Marathon," which involves playing the largest number of questions, being the most preferred. CONCLUSIONS: These results suggest that serious games such as METIS are a suitable educational medium for increasing students' knowledge and interest in the field, and that competition with peers provides even greater motivation to engage with the learning content.

Immunoproteasome deficiency results in age-dependent development of epilepsy.

The immunoproteasome is a central protease complex required for optimal antigen presentation. Immunoproteasome activity is also associated with facilitating the degradation of misfolded and oxidized proteins, which prevents cellular stress. While extensively studied during diseases with increasing evidence suggesting a role for the immunoproteasome during pathological conditions including neurodegenerative diseases, this enzyme complex is believed to be mainly not expressed in the healthy brain. In this study, we show an age-dependent increase in polyubiquitination in the brains of wild-type mice, accompanied by an induction of immunoproteasomes, which was most prominent in neurons and microglia. In contrast, mice completely lacking immunoproteasomes (triple-knockout mice), displayed a strong increase in polyubiquitinated proteins already in the young brain and developed spontaneous epileptic seizures, beginning at the age of 6 months. Injections of kainic acid led to high epilepsy-related mortality of aged triple-knockout mice, confirming increased pathological hyperexcitability states. Notably, the expression of the immunoproteasome was reduced in the brains of patients suffering from epilepsy. In addition, the aged triple-knockout mice showed increased anxiety, tau hyperphosphorylation and degeneration of Purkinje cell population with the resulting ataxic symptoms and locomotion alterations. Collectively, our study suggests a critical role for the immunoproteasome in the maintenance of a healthy brain during ageing.

DRAC 2022: A public benchmark for diabetic retinopathy analysis on ultra-wide optical coherence tomography angiography images.

We described a challenge named "DRAC - Diabetic Retinopathy Analysis Challenge" in conjunction with the 25th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI 2022). Within this challenge, we provided the DRAC datset, an ultra-wide optical coherence tomography angiography (UW-OCTA) dataset (1,103 images), addressing three primary clinical tasks: diabetic retinopathy (DR) lesion segmentation, image quality assessment, and DR grading. The scientific community responded positively to the challenge, with 11, 12, and 13 teams submitting different solutions for these three tasks, respectively. This paper presents a concise summary and analysis of the top-performing solutions and results across all challenge tasks. These solutions could provide practical guidance for developing accurate classification and segmentation models for image quality assessment and DR diagnosis using UW-OCTA images, potentially improving the diagnostic capabilities of healthcare professionals. The dataset has been released to support the development of computer-aided diagnostic systems for DR evaluation.