MIPS Seminar: “Tiny Bubbles, Big Impact: Exploring applications of nanobubbles in ultrasound molecular imaging and therapy”
Agata A. Exner, Ph.D.
Professor of Radiology and Biomedical Engineering
Department of Radiology
Case Western Reserve
Location: Beckman Center, B230
2:00pm – 3:00pm Seminar & Discussion
ABSTRACT
Sub-micron shell stabilized gas bubbles (aka nanobubbles (NB) or ultrafine bubbles) have gained momentum as a robust contrast agent for molecular imaging and therapy using ultrasound. The small size, extended stability and high concentration of nanobubbles make them an ideal tool for new applications of contrast enhanced ultrasound and ultra-
sound-mediated therapy, especially in oncology-related problems. Compared to microbub-bles, nanobubbles can provide superior tumor delineation, identify biomarkers on the vascu-lature and on tumors cells and facilitate drug and gene delivery into tumor tissue. The pat-terns of tissue enhancement under nonlinear ultrasound imaging of nanobubbles are distinct from conventional microbubbles especially in tissues exhibiting vascular hyperper-meability. Specifically, NB kinetics, quantified via time intensity curve analysis, typically show a marked delay in the washout rate and significantly increased area under the curve compared to larger bubbles. This effect is further enhanced by molecular targeting to cellular biomarkers, such as the prostate specific membrane antigen (PSMA) or the receptor protein tyrosine phosphatase, PTPmu. The unique contrast enhancement dynamics of nanobubbles are likely to be a result of direct bubble extravasation and prolonged retention of intact bubbles in target tissue. Thus, understanding the underlying mechanisms behind the unique nanobubble behavior can be the driver of significant future innovations in contrast enhanced ultrasound imaging applications. This presentation will discuss the fundamental challenges with nanobubble formulation and characterization and will showcase how the unique fea-tures of nanobubbles can be leveraged to improve disease detection and treatment using ultrasound.
MIPS Seminar
2:00-2:45 PM | Prof. Pawel Moskal
“Positronium Imaging with the J-PET Scanner”
Head of the Department of Experimental Particle Physics and Applications
Marian Smoluchowski Institute of Physics
Jagiellonian University, 30-348 Krakow, Poland
2:45-3:30 PM | Prof. Ewa Stepien
“Preclinical studies of positronium and extracellular vesicles biomarkers”
Head of the Department of Medical Physics
Marian Smoluchowski Institute of Physics
Jagiellonian University, 30-348 Krakow, Poland
ABSTRACT
As modern medicine develops towards personalized treatment of patients, there is a need for highly specific and sensitive tests to diagnose disease. Our research aims at improvement of specificity of positron emission tomography (PET) in assessment of cancer by use of positronium as a theranostic agent. During PET scanning about 40% of positron annihilations occur through the creation of positronium. “Positronium,” which may be formed in human tissues in the intramolecular spaces, is an exotic atom composed of an electron from tissue and the positron emitted by the radioinuclide. Positronium decay in the patient body is sensitive to the nanostructure and metabolism of human tissues. This phenomenon is not used in present PET diagnostics, yet it is in principle possible to exploit such environment modified properties of positronium as diagnostic biomarkers for cancer assessment. Our first in-vitro studies have shown differences of the positronium mean lifetime and production probability in healthy and cancerous tissues, indicating that they may be used as indicators for in-vivo cancer classification. For the application in medical diagnostics, the properties of positronium atoms need to be determined in a spatially resolved manner. For that purpose we have developed a method of positronium lifetime imaging in which the lifetime and position of positronium atoms are determined on an event-by-event basis. This method requires application of β+ decaying isotope that also emits a prompt gamma ray. We will argue that with total-body PET scanners, the sensitivity of positronium lifetime imaging, which requires coincident registration of the back-to-back annihilation photons and the prompt gamma, is comparable to the sensitivities for metabolic imaging with standard PET scanners.
Our research involves also development of diagnostic methods based on the extracellular vesicles (EVs), which are micro and nano-sized, closed membrane fragments. They are produced by native cells to facilitate the transfer of different signaling factors, structural proteins, nucleic acids or lipids even to distant cells. They are present in all body fluids and they are specific to their parental cells.
Our presentation will be divided into two parts. In the first, the method of positronium imaging and the pilot positronium images obtained with the J-PET detector (the first PET system built based on plastic scintillators) will be reported. This part of the presentation will include also description and perspectives of development of the J-PET technology in view of total-body PET imaging. The second part will concern preliminary results of the preclinical studies of positronium properties in cancerous and healthy tissues sampled from patients as well as in the frozen and living healthy and cancer skin cells in-vitro. The second part will include also description of the novel method for the diagnosis of diabetes and melanoma based on EVs used as biomarkers and drug delivery systems.
References:
P. Moskal, …. E. Ł. Stępień et al., Phys. Med. Biol. 64 (2019) 055017
- Moskal, B. Jasinska, E. Ł. Stępień, S. Bass, Nature Reviews Physics 1 (2019) 527
- Roman M… .E. Ł. Stępień, Nanomedicine 17 (2019) 137
- Ł. Stępień et al., Theranostics 8 (2018) 3874
Hosted by: Craig Levin, Ph.D.
Sponsored by the Molecular Imaging Program at Stanford and the Department of Radiology
Please note this seminar is now cancelled and will be rescheduled for a later date.
MIPS Seminar: Investigating and Imaging key molecular switches associated with Acquirement of Platinum-Taxol resistance in Epithelial Ovarian Cancer
Pritha Ray, Ph.D.
Principal Investigator & Scientific Officer F
Imaging Cell Signaling & Therapeutics Lab
ACTREC, Tata Memorial Center
Navi Mumbai, India
Please note this seminar is now cancelled and will be rescheduled for a future date. Please contact Ashley Williams (ashleylw@stanford.edu) with any questions or concerns. Thank you for your understanding!
CEDSS: “The First Cell and the Human Cost of going after Cancer’s last”
Chan Soon-Shiong Professor of Medicine
Director, Myelodysplastic Syndrome Center
Columbia University Medical Center
Thursday MIPS Roundtable: “Ask the Radiologist about COVID-19”
Hosted by Dr. Heike Daldrup-Link & Dr. Gunilla Jacobson
Join us virtually to ask anything you would like to know about COVID-19 and the current status in our community. This week we will open the floor for questions. Please prepare questions related to COVID-19. Feel free to submit questions in advance to Ashley Williams (ashleylw@stanford.edu) or submit them in the chat on Zoom.
Meeting URL: https://stanford.zoom.us/j/186504700
Dial: +1 650 724 9799 or +1 833 302 1536
Meeting ID: 186 504 700c talking about the future of medicine and science.
Mini-Grand Rounds: Emerging treatment strategies for COVID-19
Aruna Subramanian, MD
Clinical Professor, Medicine
Stanford University
David Ha, PharmD
Infectious Disease Resident
Stanford University
7:00am – 7:30am, Zoom
The Stanford Radiology Mini-Grand Round live session events are by invitation only. Invites with link to Zoom video will be sent via email to Department faculty and staff only. Recordings will be made available to the public shortly after the event.
Mini-Grand Rounds: Effective faculty-trainee workflow and education during the COVID-19 pandemic
Payam Massaband, MD
Clinical Associate Professor, Radiology
Stanford University
7:00am – 7:30am, Zoom
The Stanford Radiology Mini-Grand Round live session events are by invitation only. Invites with link to Zoom video will be sent via email to Department faculty and staff only. Recordings will be made available to the public shortly after the event.
Thursday MIPS Roundtable
Hosted by Dr. Kathy Ferrara & Dr. Gunilla Jacobson
Join us virtually to ask anything you would like to know about career plans, collaborations, new expertise and online lectures during the shutdown. Feel free to submit questions in advance to Ashley Williams (ashleylw@stanford.edu) or submit them in the chat on Zoom.
1:30-2:00 PM | Dr. Kathy Ferrara, Ph.D.
“Developing a career plan, collaborations and new expertise during the shutdown”
Professor of Radiology
Stanford University
2:00-2:30 PM | Dr. Angie Louie, Ph.D.
“How to create online lectures using Camtasia, Playposit and Canvas”
Professor of Biomedical Engineering
UC Davis
Meeting URL: https://stanford.zoom.us/j/186504700
Dial: +1 650 724 9799 or +1 833 302 1536
Meeting ID: 186 504 700
Mini-Grand Rounds: CoVID19: Lessons learned from the global response
Michele Barry, MD, FACP
Drs. Ben & A. Jess Shenson Professor
Senior Associate Dean, Global Health
Director, Center for Innovation in Global Health
Professor of Medicine & Senior Fellow at the Woods Institute and at the Freeman Spogli Institute
7:00am – 7:30am, Zoom
The Stanford Radiology Mini-Grand Round live session events are by invitation only. Invites with link to Zoom video will be sent via email to Department faculty and staff only. Recordings will be made available to the public shortly after the event.
Mini-Grand Rounds: How to stay productive during the COVID-19 pandemic
Garry Gold, MD
Vice Chair, Research and Organization
Professor, Radiology
Stanford University
7:00am – 7:30am, Zoom
The Stanford Radiology Mini-Grand Round live session events are by invitation only. Invites with link to Zoom video will be sent via email to Department faculty and staff only. Recordings will be made available to the public shortly after the event.