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Vogt, S.

Publications and source records attributed to Vogt, S..

3 recordsLinked to original sources

A new universal pore measurement and clustering approach for surgical meshes

The pore structure and pore size is a crucial characteristic of surgical meshes. A huge amount of different approaches for mesh classification based on pore size or materials are available. It is difficult to use these classification methods because of the large variety in knitting structures and pore shapes. No agreement on an established method to measure the pore size is available despite the fact that the surgical community agrees that pore size and geometry are crucial factors for the result of a hernia repair. In this publication a new approach to characterize meshes based on their pore shape and pore size is presented. The pore size is defined by the largest inscribed circle within a mesh pore and the smallest circumscribed circle outside the pore, in addition to hence calculated values. This allows a characterization with regards to tissue ingrowth and bridging behavior. The measurements are made using the scientific image processing software ImageJ and additional customized software plug-in. Since the program ImageJ is public domain and the plug-ins are available, the measurements can be reproduced. Furthermore, the presented pore descriptions can also be used for manual pore size verification.

bioengineering

Optogenetic silencing of primary afferents reduces evoked and ongoing bladder pain

Patients with interstitial cystitis/bladder pain syndrome (IC/BPS) suffer from chronic pain that severely affects quality of life. Although the underlying pathophysiology is not well understood, inhibition of bladder sensory afferents temporarily relieves pain. Here, we explored the possibility that optogenetic inhibition of bladder sensory afferents could be used to modulate bladder pain. Specifically, we chose to study the role of Nav1.8+ sensory afferents before and after induction of a mouse model of bladder pain. The light-activated inhibitory proton pump Archaerhodopsin (Arch) was expressed under control of the Nav1.8+ promoter to selectively silence these neurons. Optically silencing Nav1.8+ afferents significantly blunted the evoked visceromotor response to bladder distension and led to small but significant changes in bladder function. To study of the role of these fibers in freely behaving mice, we developed a fully implantable, flexible, wirelessly powered optoelectronic system for the long-term manipulation of bladder afferent expressed opsins. We found that optogenetic inhibition of Nav1.8+ fibers reduced both ongoing pain and evoked cutaneous hypersensitivity in the context of cystitis, but had no effect in uninjured, naive mice. These results suggest that selective optogenetic silencing of bladder afferents may represent a potential future therapeutic strategy for the treatment of bladder pain.

neuroscience

Cobalt enrichment in anaerobic microbial cocultures revealed by synchrotron X-ray fluorescence imaging

Metal cofactors are required for many enzymes in anaerobic microbial respiration. This study examined iron, cobalt, nickel, copper, and zinc in cellular and abiotic phases at the single-cell scale for a sulfate-reducing bacterium (Desulfococcus multivorans) and a methanogenic archaeon (Methanosarcina acetivorans) using synchrotron x-ray fluorescence microscopy. Relative abundances of cellular metals were also measured by inductively coupled plasma mass spectrometry. For both species, zinc and iron were consistently the most abundant cellular metals. M. acetivorans contained higher nickel and cobalt content than D. multivorans, likely due to elevated metal requirements for methylotrophic methanogenesis. Cocultures contained spheroid zinc sulfides and cobalt/copper-sulfides.

microbiology