Karen L. Bentley, M.S.

Ms. (de Mesy) Bentley is currently, the Director of the Electron Microscopy Shared Resource and has over 30 years of teaching and Electron Microscopy based diagnostic experience in Ultrastructural Pathology, Immunoelectron Microscopy labeling using gold-tagged secondary antibodies, Hematology, Dental Research, Infectious Agents, Biofilm Formation, Nanoparticle Characterization, Morphometric Analysis and X-ray Dispersive Spectroscopy using both Transmission and Scanning Electron Microscopes.

Ms. Bentley has published in the Journal of Orthopaedic Research in 2021, the first 3-dimensional volume reconstruction (cover of journal) of 264 consecutive 60 nm epoxy sections of Stapylococcus aureus invading the Osteocyte-Lacuno Canalicular Network (OLCN). This 3D rendering allowed us to assess that 70% of the OLCN were invaded by S. aureus, while the remaining 30% non-infected canaliculi appeared to be resistant to infection. This observation has led us to hypothesize that viable osteocytes of the OLCN can respond and resist infection, opening future research directions to explain the paradox of adjacent uninfected canaliculi and life long deep bone infection in patients with chronic osteomyelitis. This work was done in collaboration with Dr. Edward Schwarz and Dr. Jonathan Leckenby.

Previously in 2011, Ms. Bentley had been recruited by Dr. Edward Schwarz, the Director of the Center for Musculoskeletal Research in Orthopaedics, to investigate and analyze a mouse model of Staphylococcus aureus (MRSA and MSSA strains) infected implants and biofilm formation using scanning electron microscopy (SEM) that resulted in two Journal of Orthopaedic Research covers. In 2014, Ms. Bentley initiated the first transmission electron microscopy (TEM) studies on infected mouse bone which had surrounded the biofilm laden implants. Ms. Bentley's high magnification TEM study led to the discovery of S. aureus' deforming into submicron rod-shaped bacteria to colonize the OLCN of bone. This revealed for the first time how S. aureus, normally a round non-motile 1-1.5 micron sized bacteria, becomes rod-shaped to enter (using asymmetric binary fission) the submicron (0.4-0.2 micron diameter) canaliculi within live bone. This finding was published in the Journal of Bone and Mineral Research in May, 2017 and in 2016 an electron micrograph from her study was also chosen for a book cover, Osteoimmunology, 2nd Ed.

Ms Bentley has also authored and co-authored over 80 research publications resulting from her years of collaborative TEM and SEM imaging support to researchers here at the University. URMC Researchers who require high magnification imaging support can request a consultation and an estimate of cost prior to starting a research project. This facility provides full wet-lab services for tissue/cells processing, embedding, sectioning and utilizes a Hitachi 7650 TEM/STEM electron microscope with an attached 11 megapixel Gatan digital camera system. It is located in the basement of the Medical School building. A Zeiss Auriga scanning electron microscope housed in Wilmot Hall on the River Campus is used by the laboratory when performing SEM studies.