Biology subjects

Welter, M.

Publications and source records attributed to Welter, M..

3 recordsLinked to original sources

bioRxiv2025

OXA-1207, a new OXA-48-type carbapenem-hydrolysing class D beta lactamase from Escherichia coli

1.We present the characterisation of OXA-1207, a novel, plasmid-encoded OXA-48-like carbapenemase identified in two unrelated Escherichia coli (sequence type (ST) ST405 and ST4405) isolates from hospital patients in Germany. OXA-1207 is closely related to OXA-181, differing by two amino acid substitutions (214G and 244W). The blaOXA-1207 gene was located on a self-transmissible IncFIC plasmids (pOXA-1207) featuring a conserved backbone and the novel {Delta}Tn6361 transposon structure, which derived from IncX3 plasmids carrying blaOXA-181. Notably, pOXA-1207 exhibited an exceptionally high conjugation frequency (mean 1.2 x 10-1) to E. coli, surpassing the typical rates reported for widely distributed OXA-48 plasmids. Analysis of public genomic datasets identified 40 E. coli isolates carrying blaOXA-1207, belonging to diverse high-risk clonal lineages (ST167, ST405 and ST410). The isolates originated from multiple continents, indicating global dissemination. These findings highlight OXA-1207 as an emerging and concerning resistance determinant with enhanced transmissibility and emphasise the need for continued molecular surveillance of OXA-48-like carbapenemases.

microbiology↗

bioRxiv2018

Adaption of artificial microvascular networks

We explored the application of the adaption algorithm introduced by Secomb et. al. to artificial blood vessel networks and find that the resulting networks to not obey Murrays law. The reported analysis and visual examples document the contrast between two different types of networks. We conjecture that an interrupt of an established signaling cascade could be a hallmark of solid vascular tumors.

cancer biology↗

bioRxiv2017

Tumorcode - A framework to simulate vascularized tumors

During the past years our group published several articles using computer simulations to address the complex interaction of tumors and the vasculature as underlying transport network. Advances in imaging and lab techniques pushed in vitro research of tumor spheroids forward and animal models as well as clinical studies provided more insights to single processes taking part in tumor growth, however, an overall picture is still missing. Computer simulations are a none-invasive option to cumulate current knowledge and form a quasi in vivo system. In our software, several known models were assembled into a multi-scale approach which allows to study length scales relevant for clinical applications.\n\nWe release our code to the public domain, together with a detailed description of the implementation and several examples, with the hope of usage and futher development by the community. Justification for the included algorithms and the biological models was obtained in previous publications, here we summarize technical aspects following the workflow of a typical simulation procedure.

biophysics↗