191 research outputs found
Ambrotype of two men sitting on a bench at Table Rock near the Horseshoe Falls, ca. 1860.
An ambrotype of two men sitting on a bench at Table Rock near the Horseshoe Falls, ca. 1860
Combining Biocompatible and Biodegradable Scaffolds and Cold Atmospheric Plasma for Chronic Wound Regeneration
Skin regeneration is a quite complex process. Epidermal differentiation alone takes about 30 days and is highly regulated. Wounds, especially chronic wounds, affect 2% to 3% of the elderly population and comprise a heterogeneous group of diseases. The prevailing reasons to develop skin wounds include venous and/or arterial circulatory disorders, diabetes, or constant pressure to the skin (decubitus). The hallmarks of modern wound treatment include debridement of dead tissue, disinfection, wound dressings that keep the wound moist but still allow air exchange, and compression bandages. Despite all these efforts there is still a huge treatment resistance and wounds will not heal. This calls for new and more efficient treatment options in combination with novel biocompatible skin scaffolds. Cold atmospheric pressure plasma (CAP) is such an innovative addition to the treatment armamentarium. In one CAP application, antimicrobial effects, wound acidification, enhanced microcirculations and cell stimulation can be achieved. It is evident that CAP treatment, in combination with novel bioengineered, biocompatible and biodegradable electrospun scaffolds, has the potential of fostering wound healing by promoting remodeling and epithelialization along such temporarily applied skin replacement scaffolds
Development of a Novel Valve-Controlled Drug-Elutable Microstent for Microinvasive Glaucoma Surgery: In Vitro and Preclinical In Vivo Studies
Purpose: Microinvasive glaucoma surgery (MIGS) has become an important treatment approach for primary open-angle glaucoma, although the safe and long-term effective lowering of intraocular pressure with currently available implants for MIGS is not yet achieved to a satisfactory extent. The study focusses on the development and in vitro and in vivo testing of a novel microstent for MIGS. Methods: A silicone elastomer-based microstent was developed. Implants were manufactured using dip coating, fs-laser cutting, and spray coating. Within the current study no antifibrotic drug was loaded into the device. Sterilized microstents were analyzed in vitro regarding pressure–flow characteristics and biocompatibility. Six New Zealand white rabbits were implanted with a microstent draining the aqueous humor from the anterior chamber into the subconjunctival space. Drainage efficacy was evaluated using oculopressure tonometry as a transient glaucoma model. Noninvasive imaging was performed. Results: Microstents were manufactured successfully and characterized in vitro. Implantation in vivo was successful for four animals with additional device fixation. Without additional fixation, dislocation of microstents was found in two animals. Safe and effective intraocular pressure reduction was observed for the four eyes with correctly implanted microstent during the 6-month trial period. Conclusions: The described microstent represents an innovative treatment approach for MIGS. The incorporation of a selectively antifibrotic drug into the microstent drugelutable coating will be addressed in future investigations. Translational Relevance: The current preclinical study successfully provided proof of concept for our microstent for MIGS which is suitable for safe and effective intraocular pressure reduction and offers promising perspectives for the clinical management of glaucoma
Utilization of a highly adaptable murine air pouch model for minimally invasive testing of the inflammatory potential of biomaterials
Introduction: The biocompatibility of an implanted material strongly determines the subsequent host immune response. After insertion into the body, each medical device causes tissue reactions. How intense and long-lasting these are is defined by the material properties. The so-called foreign body reaction is a reaction leading to the inflammation and wound healing process after implantation. The constantly expanding field of implant technology and the growing areas of application make optimization and adaptation of the materials used inevitable.Methods: In this study, modified liquid silicone rubber (LSR) and two of the most commonly used thermoplastic polyurethanes (TPU) were compared in terms of induced inflammatory response in the body. We evaluated the production of inflammatory cytokines, infiltration of inflammatory cells and encapsulation of foreign bodies in a subcutaneous air-pouch model in mice. In this model, the material is applied in a minimally invasive procedure via a cannula and in one piece, which allows material testing without destroying or crushing the material and thus studying an intact implant surface. The study design includes short-term (6Â h) and long-term (10Â days) analysis of the host response to the implanted materials. Air-pouch-infiltrating cells were determined by flow cytometry after 6Â h and 10Â days. Inflammation, fibrosis and angiogenesis markers were analyzed in the capsular tissue by qPCR after 10Â days.Results: The foreign body reaction was investigated by macroscopic evaluation and scanning electron microscopy (SEM). Increased leukocyte infiltration was observed in the air-pouch after 6Â h, but it markedly diminished after 10Â days. After 10Â days, capsule formations were observed around the materials without visible inflammatory cells.Discussion: For biocompatibility testing materials are often implanted in muscle tissue. These test methods are not sufficiently conclusive, especially for materials that are intended to come into contact with blood. Our study primarily shows that the presented model is a highly adaptable and minimally invasive test system to test the inflammatory potential of and foreign body reaction to candidate materials and offers more precise analysis options by means of flow cytometry
Development of a biodegradable microstent for minimally invasive treatment of Fallopian tube occlusions
Obstructions of the Fallopian tube represent one of the most common reasons for an unfulfilled desire to have children. Microstent technology opens up new therapeutic possibilities to restore the natural lumen of the Fallopian tube within a single treatment. Within the current work we developed a self-expandable biodegradable microstent for gynecological applications. Based on a novel microstent design, prototypes were manufactured from poly-L-lactide tubing by means of fs-laser cutting. Microstent prototypes were characterized morphologically by means of scanning electron microscopy and biaxial laser scanning. As manufactured, a microstents outside diameter of about 2.3 mm and a strut thickness/width of about 114 µm/103 µm was measured. Mechanical characterization of microstents included bending as well as crimping and release behavior. After crimping to a minimum diameter of 0.8 mm and consecutive release, a microstent recovery to a diameter of 1.8 mm was found. Therefore, proof-of-concept for the self-expandable microstent could be successfully provided. © 2020 by Walter de Gruyter Berlin/Boston 2020
Progress and challenges in the development of novel implant concepts for cardiovascular, ophthalmologic and otolaryngologic applications
Medical device innovations may contribute to the reconstruction of biological functions, and thereby improve the quality of patients’ lives, as well as extend their life expectancy. The coordinated research project “RESPONSE - Partnership for Innovation in Implant Technology” (BMBF program Twenty20 - Partnership for Innovation, 2014 - 2021) is focusing on the development of novel concepts for implantable medical devices for cardiovascular, ophthalmologic and otorhinolaryngologic applications. The joint research efforts of academia and industry in the RESPONSE consortium address the challenges in implant design, biofunctionalization, process development and production. Particular attention is paid to the process of translation of medical device innovations, cost analysis, as well as health technology assessment
Reconstruction of biological functions: novel implant concepts for cardiovascular, ophthal-mologic and otolaryngologic applications
Biomedical engineering innovations towards the reconstruction of biological functions seek to improve the quality of patients’ lives. The coordinated research project “RESPONSE – Partnership for Innovation in Implant Technology” (BMBF program Twenty20 – Partnership for Innovation, 2014 - 2021) is focusing on the development of novel concepts for (i) cardiovascular scaffolds, glaucoma and ENT stents, (ii) transcatheter heart valves and venous valves, (iii) polymeric implants and polymer/drug formulations. Current clinical paradigm shifts, fostered by the progress in implant technology and a growing global demand, frame the background for the joint research efforts of academia and industry in the RESPONSE consortium
Medical device innovations for cardiovascular, ophthalmologic and otolaryngologic applications
The consortium RESPONSE is a cooperation between partners from science and industry within the BMBF-Program “Twenty20 - Partnership for Innovation”, 2014-2021. RESPONSE gives its partners opportunities to put medical device innovations into practice more efficiently. In order to accelerate innovation processes, joint efforts are being made along the entire translation chain. RESPONSE is focusing on the development of novel concepts of implantable medical devices for cardiovascular, ophthalmologic and ENT application. Platform technology approaches are being used to extend the range of device applications. See also: www.response.uni-rostock.d
Transfer activities for cardiovascular, ophthalmologic and otolaryngologic medical device innovations
The consortium RESPONSE is a cooperation of partners from science and industry within the BMBFProgram “Twenty20 - Partnership for Innovation”, 2014- 2021. Current efforts are being made towards the transfer of new products, technologies and processes in the field of medical devices. Here, RESPONSE is focusing on novel concepts of implantable medical devices for cardiovascular, ophthalmologic and otolaryngologic application. Platform technology approaches, such as drug delivery systems for responsive functionalized implants or smart implant technologies, are being used to enable new applications
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