Evaluation of whole-genome enrichment and sequencing of T. pallidum from FFPE samples after 75 years.

The recent developments in genomic sequencing have permitted the publication of many new complete genome sequences of Treponema pallidum pallidum, the bacterium responsible for syphilis, which has led to a new understanding of its phylogeny and diversity. However, few archived samples are available, because of the degradability of the bacterium and the difficulties in preservation. We present a complete genome obtained from a Formalin-Fixed Paraffin-Embedded (FFPE) organ sample from 1947, kept at the Strasbourg Faculty of Medicine. This is the preliminary, proof-of concept study of this collection/biobank of more than 1.5 million FFPE samples and the evaluation of the feasibility of genomic analyses. We demonstrate here that even degraded DNA from fragile bacteria can be recovered from 75-year-old FFPE samples and therefore propose that such collections as this one can function as sources of biological material for genetic studies of pathogens, cancer, or even the historical human population itself.

Histopathology slides from medical research to medical practice in interwar Strasbourg.

Histopathologists have been interested in cancer since the beginning of cellular theory. Rudolf Virchow and Julius Cohnheim defined cancer as a disease due to specific changes in tissues; cancer was thus considered a "pathologist's disease." Virchow emphasized the principles of biopsy and its value in the diagnosis of malignant tumours, but he himself did not promote it as an instrument for diagnosis. In the nineteenth century, in fact, cancer was a pathologists' disease in research only, not in diagnosis. By the mid-twentieth century, pathologists figured in medical practice as mediators between alternative therapeutic solutions. Histopathology entered a new arena, medical practice. In this paper, the process through which microscope slides moved from histopathology research to medical practice will be explored in detail with the aim of understanding how medical research integrates routine medical practices. The quasi-inherent character of scientific knowledge as relevant to medical practice is not taken for granted here. Through a study of medical school laboratory records from the interwar period in Strasbourg, I argue that pathologists could direct patients to specific forms of therapy on the basis of microscopic slides of cancer cells because they had defined (and re-defined) cancers by contributing to establishing radiation therapy practices.