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Rohfritsch, A.

Publications and source records attributed to Rohfritsch, A..

2 recordsLinked to original sources

Impact of Focused Ultrasound on the Cellular Network of Liver Tissue: A New Perspective for Thermal Lesion Detection

ObjectiveThe noninvasive characterization of soft tissue microstructure remains challenging and has a significant clinical impact on diagnosis and therapy monitoring. During high-intensity focused ultrasound (HIFU) treatments, coagulation necrosis is accompanied by mechanical changes. The objective of this work is to use the anisotropy arising at the cellular level as a new biomarker for treatment evaluation. ApproachWe demonstrate that HIFU induces anisotropic alterations in the cellular architecture of liver tissue, which are detectable through the angular dependence of the backscattering coefficient (BSC). Also, in vivo experiments reveal a distinct anisotropic histological pattern localized in the HIFU-treated region. Main resultsWe show that the degree of anisotropy deduced from BSC measurements is correlated with the histological observations. Moreover, anisotropy increases with delivered energy, providing a quantitative link between treatment parameters and tissue response. SignificanceThese findings establish BSC anisotropy as a previously unexplored signature of thermal lesions, offering a promising approach for monitoring and feedback in thermal therapeutic ultrasound applications. This breakthrough could open the door to next-generation imaging tools, accelerating the widespread adoption of this highly effective therapeutic modality.

biophysics↗

Population genomics of bank vole populations reveals associations between immune related genes and the epidemiology of Puumala hantavirus in Sweden

Infectious pathogens are major selective forces acting on individuals. The recent advent of high-throughput sequencing technologies now enables to investigate the genetic bases of resistance/susceptibility to infections in non-model organisms. From an evolutionary perspective, the analysis of the genetic diversity observed at these genes in natural populations provides insight into the mechanisms maintaining polymorphism and their epidemiological consequences. We explored these questions in the context of the interactions between Puumala hantavirus (PUUV) and its reservoir host, the bank vole Myodes glareolus. Despite the continuous spatial distribution of M. glareolus in Europe, PUUV distribution is strongly heterogeneous. Different defence strategies might have evolved in bank voles as a result of co-adaptation with PUUV, which may in turn reinforce spatial heterogeneity in PUUV distribution. We performed a genome scan study of six bank vole populations sampled along a North/South transect in Sweden, including PUUV endemic and non-endemic areas. We combined candidate gene analyses (Tlr4, Tlr7, Mx2 genes) and high throughput sequencing of RAD (Restriction-site Associated DNA) markers. We found evidence for outlier loci showing high levels of genetic differentiation. Ten outliers among the 52 that matched to mouse protein-coding genes corresponded to immune related genes and were detected using ecological associations with variations in PUUV prevalence. One third of the enriched pathways concerned immune processes, including platelet activation and TLR pathway. In the future, functional experimentations should enable to confirm the role of these these immune related genes with regard to the interactions between M. glareolus and PUUV.

evolutionary biology↗