TY - JOUR A1 - Sudarevic, Boban A1 - Troya, Joel A1 - Fuchs, Karl-Hermann A1 - Hann, Alexander A1 - Vereczkei, Andras A1 - Meining, Alexander T1 - Design and development of a flexible 3D-printed endoscopic grasping instrument JF - Applied Sciences N2 - (1) Background: Interventional endoscopic procedures are growing more popular, requiring innovative instruments and novel techniques. Three-dimensional printing has demonstrated great potential for the rapid development of prototypes that can be used for the early assessment of various concepts. In this work, we present the development of a flexible endoscopic instrument and explore its potential benefits. (2) Methods: The properties of the instrument, such as its maneuverability, flexibility, and bending force, were evaluated in a series of bench tests. Additionally, the effectiveness of the instrument was evaluated in an ex vivo porcine model by medical experts, who graded its properties and performance. Furthermore, the time necessary to complete various interventional endoscopic tasks was recorded. (3) Results: The instrument achieved bending angles of ±216° while achieving a bending force of 7.85 (±0.53) Newtons. The time needed to reach the operating region was 120 s median, while it took 70 s median to insert an object in a cavity. Furthermore, it took 220 s median to insert the instrument and remove an object from the cavity. (4) Conclusions: This study presents the development of a flexible endoscopic instrument using three-dimensional printing technology and its evaluation. The instrument demonstrated high bending angles and forces, and superior properties compared to the current state of the art. Furthermore, it was able to complete various interventional endoscopic tasks in minimal time, thus potentially leading to the improved safety and effectiveness of interventional endoscopic procedures in the future. KW - endoscopy KW - endoscopic intervention KW - 3D printing KW - endoscopic instruments KW - minimally invasive surgery KW - rapid prototyping Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-319186 SN - 2076-3417 VL - 13 IS - 9 ER - TY - JOUR A1 - Fuchs, Andreas A1 - Hartmann, Stefan A1 - Ernestus, Karen A1 - Mutzbauer, Grit A1 - Linz, Christian A1 - Brands, Roman C. A1 - Kübler, Alexander C. A1 - Müller-Richter, Urs D. A. T1 - Mandibular intraosseous pseudocarcinomatous hyperplasia: a case report JF - Journal of Medical Case Reports N2 - Background Mandibular pseudocarcinomatous hyperplasia is a rare and generally benign pathology. We report on one of these rare cases. Case presentation The case history of a 73-year-old white man stated that he had a carcinoma of the oropharynx, which was primarily treated with radiotherapy and chemotherapy 4 years prior. As a result of radiotherapy he developed an osteoradionecrosis of his mandible and a consecutive pathological fracture of his left mandibular angle. Subsequent osteosynthesis was performed with a reconstruction plate. When we first saw him, his reconstruction plate was partially exposed with intraoral and extraoral fistulation. The resected bone of his defect-bordering jaw showed the typical pathohistological findings of an intraosseous mandibular pseudocarcinomatous hyperplasia. After a first reconstruction attempt with an iliac crest graft failed, definitive reconstruction of his mandible with a microvascular anastomosed fibula graft was achieved. Conclusions Intraosseous pseudocarcinomatous hyperplasia of the mandible is a rare differential diagnosis in maxillofacial surgery. Besides other benign epithelial neoplasms, such as calcifying epithelial odontogenic tumor, squamous odontogenic tumor, or different forms of ameloblastoma, the far more frequent invasive squamous cell carcinoma needs to be excluded. A misinterpretation of pseudocarcinomatous hyperplasia as squamous cell carcinoma must be avoided because it can lead to a massive overtreatment. KW - intraosseous KW - case report KW - pseudocarcinomatous hyperplasia KW - mandible Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146873 VL - 16 IS - 268 ER - TY - JOUR A1 - Kleinschnitz, Christoph A1 - Grund, Henrike A1 - Wingler, Kirstin A1 - Armitage, Melanie E. A1 - Jones, Emma A1 - Mittal, Manish A1 - Barit, David A1 - Schwarz, Tobias A1 - Geis, Christian A1 - Kraft, Peter A1 - Barthel, Konstanze A1 - Schuhmann, Michael K. A1 - Herrmann, Alexander M. A1 - Meuth, Sven G. A1 - Stoll, Guido A1 - Meurer, Sabine A1 - Schrewe, Anja A1 - Becker, Lore A1 - Gailus-Durner, Valerie A1 - Fuchs, Helmut A1 - Klopstock, Thomas A1 - de Angelis, Martin Hrabe A1 - Jandeleit-Dahm, Karin A1 - Shah, Ajay M. A1 - Weissmann, Norbert A1 - Schmidt, Harald H. H. W. T1 - Post-Stroke Inhibition of Induced NADPH Oxidase Type 4 Prevents Oxidative Stress and Neurodegeneration N2 - Ischemic stroke is the second leading cause of death worldwide. Only one moderately effective therapy exists, albeit with contraindications that exclude 90% of the patients. This medical need contrasts with a high failure rate of more than 1,000 pre-clinical drug candidates for stroke therapies. Thus, there is a need for translatable mechanisms of neuroprotection and more rigid thresholds of relevance in pre-clinical stroke models. One such candidate mechanism is oxidative stress. However, antioxidant approaches have failed in clinical trials, and the significant sources of oxidative stress in stroke are unknown. We here identify NADPH oxidase type 4 (NOX4) as a major source of oxidative stress and an effective therapeutic target in acute stroke. Upon ischemia, NOX4 was induced in human and mouse brain. Mice deficient in NOX4 (Nox42/2) of either sex, but not those deficient for NOX1 or NOX2, were largely protected from oxidative stress, blood-brain-barrier leakage, and neuronal apoptosis, after both transient and permanent cerebral ischemia. This effect was independent of age, as elderly mice were equally protected. Restoration of oxidative stress reversed the stroke-protective phenotype in Nox42/2 mice. Application of the only validated low-molecular-weight pharmacological NADPH oxidase inhibitor, VAS2870, several hours after ischemia was as protective as deleting NOX4. The extent of neuroprotection was exceptional, resulting in significantly improved long-term neurological functions and reduced mortality. NOX4 therefore represents a major source of oxidative stress and novel class of drug target for stroke therapy. KW - Schlaganfall Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-68416 ER - TY - JOUR A1 - Czysch, Christian A1 - Medina‐Montano, Carolina A1 - Zhong, Zifu A1 - Fuchs, Alexander A1 - Stickdorn, Judith A1 - Winterwerber, Pia A1 - Schmitt, Sascha A1 - Deswarte, Kim A1 - Raabe, Marco A1 - Scherger, Maximilian A1 - Combes, Francis A1 - De Vrieze, Jana A1 - Kasmi, Sabah A1 - Sandners, Niek N. A1 - Lienenklaus, Stefan A1 - Koynov, Kaloian A1 - Räder, Hans‐Joachim A1 - Lambrecht, Bart N. A1 - David, Sunil A. A1 - Bros, Matthias A1 - Schild, Hansjörg A1 - Grabbe, Stephan A1 - De Geest, Bruno G. A1 - Nuhn, Lutz T1 - Transient Lymph Node Immune Activation by Hydrolysable Polycarbonate Nanogels JF - Advanced Functional Materials N2 - The development of controlled biodegradable materials is of fundamental importance in immunodrug delivery to spatiotemporally controlled immune stimulation but avoid systemic inflammatory side effects. Based on this, polycarbonate nanogels are developed as degradable micellar carriers for transient immunoactivation of lymph nodes. An imidazoquinoline‐type TLR7/8 agonist is covalently conjugated via reactive ester chemistry to these nanocarriers. The nanogels not only provide access to complete disintegration by the hydrolysable polymer backbone, but also demonstrate a gradual disintegration within several days at physiological conditions (PBS, pH 6.4–7.4, 37 °C). These intrinsic properties limit the lifetime of the carriers but their payload can still be successfully leveraged for immunological studies in vitro on primary immune cells as well as in vivo. For the latter, a spatiotemporal control of immune cell activation in the draining lymph node is found after subcutaneous injection. Overall, these features render polycarbonate nanogels a promising delivery system for transient activation of the immune system in lymph nodes and may consequently become very attractive for further development toward vaccination or cancer immunotherapy. Due to the intrinsic biodegradability combined with the high chemical control during the manufacturing process, these polycarbonate‐based nanogels may also be of great importance for clinical translation. KW - biodegradable KW - immunodrug delivery KW - lymph nodes KW - nanogels KW - polycarbonates Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287255 VL - 32 IS - 35 ER - TY - JOUR A1 - Straub, Anton A1 - Vollmer, Andreas A1 - Lâm, Thiên-Trí A1 - Brands, Roman C. A1 - Stapf, Maximilian A1 - Scherf-Clavel, Oliver A1 - Bittrich, Max A1 - Fuchs, Andreas A1 - Kübler, Alexander C. A1 - Hartmann, Stefan T1 - Evaluation of advanced platelet-rich fibrin (PRF) as a bio-carrier for ampicillin/sulbactam JF - Clinical Oral Investigations N2 - Objectives Mechanisms of wound healing are often impaired in patients with osteonecrosis of the jaw (ONJ). According to the guidelines for the treatment of this disease, early surgical intervention is indicated. However, surgery often faces complications such as wound healing disorders. The application of platelet-rich fibrin (PRF) after necrosectomy between bone and mucosa may constitute a promising approach to improve surgical results. An aspect that was not investigated until now is that PRF acts as a “bio-carrier” for antibiotics previously applied intravenously. Materials and methods We investigated the antimicrobial properties of PRF in 24 patients presenting ONJ undergoing systemic antibiosis with ampicillin/sulbactam. We measured the concentration of ampicillin/sulbactam in plasma and PRF and performed agar diffusion tests. Ampicillin/sulbactam was applied intravenously to the patient 10 minutes for blood sampling for PRF. No further incorporation of patients’ blood or PRF product with antibiotic drugs was obtained. Four healthy patients served as controls. Results Our results revealed that PRF is highly enriched with ampicillin/sulbactam that is released to the environment. The antibiotic concentration in PRF was comparable to the plasma concentration of ampicillin/sulbactam. The inhibition zone (IZ) of PRF was comparable to the standard ampicillin/sulbactam discs used in sensitivity testing. Conclusions The results of our study demonstrated that PRF is a reliable bio-carrier for systemic applied antibiotics and exhibits a large antimicrobial effect. Clinical relevance We describe a clinically useful feature of PRF as a bio-carrier for antibiotics. Especially when applied to poorly perfused tissues and bone such as in ONJ, the local release of antibiotics can reduce wound healing disorders like infections. KW - osteonecrosis of the jaw KW - osteoradionecrosis KW - antiresorptive drug-related osteonecrosis of the jaw KW - ARONJ KW - oral microbiome KW - agar diffusion test Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324515 VL - 26 IS - 12 ER -