Author: ehgroth

Biomedical Engineering seminar: Photoacoustic imaging and focusing in deep biological tissue

The Department of Biomedical Engineering Seminar;
Lidai Wang, Ph.D., Department of Biomedical Engineering, Washington University in St. Louis

Date: Thursday, January 29 – 1:00 pm, Room: 320 Dillman

Title: “Photoacoustic imaging and focusing in deep biological tissue”

Taking advantage of rich molecular contrasts and safe non-ionizing radiation, optical imaging has been playing increasingly important roles in biomedical applications. However, a fundamental limit of
optical imaging in biological tissue is light diffusion, which prohibits high-resolution imaging at depths beyond ~1mm. To break through this limit, we recently developed photoacoustic imaging and wavefront shaping technologies for in vivo functional imaging, early cancer detection, and focusing light into diffusive regimes. This presentation will first discuss the development of video-rate functional photoacoustic microscopy which, for the first time, enabled real-time quantitative imaging of oxygen release from single red blood cells in living tissue. Then I will introduce another functional photoacoustic imaging modality, ultrasonic-encoded photoacoustic flowgraphy, which can measure extremely slow blood flow in deep tissue with four times higher sensitivity than ultrasonic Doppler flowmetry. In addition, I will present a novel technique named nonlinear photoacoustic guided wavefront shaping (PAWS) that enables diffraction-limited optical focusing and imaging in highly scattering media such as deep biological tissue.

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Biomedical Engineering Seminar: Molecular/Cellular Photoacoustic Imaging and High Sensitivity Non-Contact Optical Detection to Laser

Biomedical Engineering seminar Tuesday January 27, 2015, MEEM 111; 
Jinjun Xia, Ph.D.,
Title: Molecular/Cellular Photoacoustic Imaging and High Sensitivity

Non-Contact Optical Detection to Laser Photoacoustic (PA) imaging is based on the detection of acoustic signals induced by the distribution of specific optical heterogeneities in targeted objects when irradiated by short laser pulses. Contrast in PA images is primarily determined by optical absorption, while spatial resolution is the same as in ultrasound. The advantages of PA imaging including low cost, non-ionizing operation, and sub-mm spatial resolution at centimeters depth, make it a promising modality to probe nanoparticle-targeted abnormalities in real time at cellular and molecular levels. However, detecting rare cell types in a heterogeneous background with strong optical scattering and absorption remains a big challenge. For example, differentiating circulating tumor cells in vivo (typically fewer than 10 cells/mL for an active tumor) among billions of erythrocytes in the blood is nearly impossible. In this presentation, I will present two newly developed techniques, magneto-motive photoacoustic (mmPA) imaging and laser induced nonlinear ultrasonic/photoacoustic imaging, which can significantly increase the sensitivity and specificity of sensing targeted cells or molecular interactions. The primary advantage of these methods is suppression of background signals through magnetic enrichment/manipulation and laser induced bubbles with gold nanospheres coated emulsion beads with simultaneous PA detection of contrast agent targeted objects. The extension of these techniques and their applications in my future research will be presented. In the instrumentation aspect, the current integrated photoacoustic (PA)/Ultrasonic(US) imaging systems use bulky, low repetition rate lasers to provide sufficient pulse energies to image at depth within the body. However, integrating these lasers with real-time clinical ultrasound scanners is problematic due to their size and cost. In this presentation, I will present an integrated PA/US imaging system that can operate at frame rates >30Hz by employing a portable, low-cost, low-pulse energy, high repetition rate, 1053nm laser and a rotating galvo-mirror system enabling rapid laser beam scanning over the imaging area. This approach is demonstrated for potential applications requiring a few centimeters of penetration. The future improvement of this system will also be presented. Non-contact optical detection for laser generated ultrasound is very attractive for its flexibility.

Current non-contact systems have relatively low sensitivity compared to contact piezoelectric detection. They are difficult to adjust, very expensive, and strongly influenced by environmental noise. Here I will present a new type of a balanced fiber-optic Sagnac interferometer as part of an all-optical laser ultrasonics (LU) pump-probe system for non-destructive testing and evaluation of aircraft composites. This new system eliminates the most of current LU drawbacks by combining a new generation of compact, inexpensive fiber lasers with new developments on fiber telecommunication optics and an optimally designed balanced probe scheme. The performance of this LU system is demonstrated on a composite sample with known defects. A system noise figure of 12.3dB above the Nyquist thermal noise limit is achieved at a rough composite surface. Biomedical applications of this system and its modifications will be presented.

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Biotechnology Research Center Research Forum Awards

Caleb Vogt
Caleb Vogt
The Eleventh Annual Research Forum sponsored by the Biotechnology Research Center was held on Wednesday, Oct. 22, and Thursday, Oct. 23. Forty-one graduate and undergraduate students conducting research in life science, biotechnology, human health and related areas presented posters. Oral presentations were also given. Speakers included Jeremy Goldman (Bio Med), Ashutosh Tiwari (Chem), Hairong Wei (SFRES), Justin Segula (SFRES graduate student), Jingtuo Zhang (Chem graduate student) and Caleb Vogt (Bio Med undergrad student).

Thank you to the participants, the judges and all who helped with another successful BRC Research Forum. A list of BRC award winners is below.

Graduate Grand Prize
Maria Gencoglu (ChE) “A New Virus Purification Process: Virus Flocculation in the Presence of Osmolytes”
Advisor: Caryn Heldt

Graduate Merit Awards
Emily Shearier (Bio Med) “Mesenchymal Stem Cell Spheroids for Therapy Following Axillary Lymph Node Dissection” Advisor: Feng Zhao

Yu Wang (Bio Med) “Building a Virtual Breast Elastography Phantom Lab Using Open Source Software”
Advisor: Jingfeng Jiang

Undergraduate Grand Prize
Caleb Vogt (Bio Med) “Human Mesenchymal Stem Cell Response to Nitric Oxide Relesasing Materials”
Advisors: Megan Frost and Feng Zhao

Undergraduate Merit Award
Mitchell Tahtinen (Bio Med) “Prevascularization of Natural Extracellular Matrix Scaffold”
Advisor: Feng Zhao

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Doing Research in a War Zone

Engineers and scientists at Michigan Technological University run into all kinds of roadblocks as they work to move their research from concept to actuality, but exploding rockets aren’t usually one of them.

When Jeremy Goldman took his family to Israel to work on his research on bioabsorbable cardiovascular stents, missiles flying overhead were just one of the facts of war that they had to worry about. Other concerns included terrorists crawling through tunnels, suicide bombers, riots, etc.
Read More

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Biomedical Engineering Graduate Seminar: R&D in the Medical Device Industry

oct24Biomedical Engineering Graduate Seminar: Orhan Soykan, Ph.D., Professor of Practice—Biomedical Engineering, Michigan Technological University; Friday, October 24; 3:00 in U113 M&M;
Sponsored by: Department of Biomedical Engineering

Title: R&D in the Medical Device Industry

A significant percentage of engineers with M.S. and Ph.D. degrees work in the medical device industry. In addition to conducting research, they also participate in the product development, technology assessment, due diligence, market research, clinical trials, preclinical studies as well as regulatory and quality assurance tasks. During the last ten years, the medical device sector followed the general industrial trends in the Unit-ed States and began to outsource a good portion of internal work to subcontractors, both at domestic and overseas locations. In this presentation, a general overview of both the large and the small medical device companies as well as the work environment of the technical staff working in this sector will be presented.

Attendees are urged to bring their questions for an interactive discussion that is planned for the last 15 minute of the seminar.

Orhan Soykan obtained his Ph.D. degree from Case Western Reserve University in 1990. O. Soykan’s career took him to engineering, academic, applied research, and business and product development positions at diverse or-ganizations such as the Military Electronics Industries (ASELSAN), the U.S. Food and Drug Administration (FDA), and Medtronic, Inc. (serving in Minneapolis and in Tokyo). He has 22 issued U.S. patents and 48 pending U.S. patent ap-plications. In January 2013, Twin Cities Business Magazine listed him as one of the “Top 500 Inventors in Minnesota.”

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Biomedical Engineering Graduate Seminar: Stem Cell-based Musculoskeletal Tissue Regeneration

oct17Biomedical Engineering Graduate Seminar: Wan-Ju Li, Phd, Department of Biomedical Engineering, University of Wisconsin-Madison; Friday, October 17; 3:00 in U113 M&M;
Sponsored by: Department of Biomedical Engineering and the Biotechnology Research Center (BRC)

Title: Stem Cell-based Musculoskeletal Tissue Regeneration

Mesenchymal stem cells (MSCs) can be isolated from several adult tissues, such as bone marrow, fat, and blood, and cultured in vitro for extensive propagation. These cells are multi-potent, and with proper biochemical or physical cues, they can differentiate into various connective tissue linage cells, such as osteoblast, chondrocyte, adipocyte, and tenocyte. Notably, transplanted allogeneic MSCs can regulate the activity of recipient’s immune cells to reduce the immune response. These unique properties make MSCs an attractive cell source for cell therapy and re-generative medicine applications.
Using MSCs to regenerate cartilage for tissue repair is a promising treatment to osteoarthritis (OA) or other cartilage defects. However, one of the challenges using MSCs for regenerative medicine is that the cells isolated from adult tissues are often composed of heterogeneous cell popu-lations, and the heterogeneity increases the difficulty of using the cells for cartilage regeneration. Another challenge is that MSCs become aged and senescent after several cell passages in vitro culture, limiting the use for clinical applications. To overcome the challenges, we derive MSCs from human embryonic stem cells (hESCs) and study the potential of hESC-MSCs for cartilage regeneration. We compare the phenotype of hESC-MSCs with that of bone marrow-derived MSCs. Flow cytometry analysis shows that MSCs and hESC-MSCs express similar cell surface markers. In terms of the potential for chondrogenesis, the mRNA transcript levels of chondrocyte-related matrix proteins and transcription factors, such as collagens type II, IX, and X, aggrecan, and Sox9, are upregulated in MSCs compared to those in hESC-MSCs during chondrogenesis, suggesting that the current differentiation protocol more effectively induces MSCs into chondrocytes than hESC-MSCs, and an improved differen-tiation protocols should be developed to induce chondrogenesis of hESC-MSCs.
For tissue engineering applications, we demonstrate a unique approach using a biomimetic scaffold, intervertebral disc (IVD) and stem cell coculture, and mechanical stimulation to tissue-engineer a biological IVD substitute. The results show that our approach provides both favorable physical and chemical cues through cell-matrix and cell-cell interactions and mechanobiological induction to enhance IVD generation ex vivo. Taken together, we have shown the potential of using stem cell and nanofabrication technologies to regenerate functional tissue for orthopedic treatment.

Professor Wan-Ju Li is the Principal Investigator of the Musculoskeletal Biology and Regenerative Medicine Laboratory at the University of Wisconsin-Madison in the United States of America. He is also an affiliated faculty member in Cellular and Molecular Biology Program, and Stem Cell and Regenerative Medicine Center. His research interests include stem cell, tissue engineering, nanobiomaterial, and skeletal biology.

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“Virtual Breast” Could Improve Cancer Detection

image113672-horizNext to lung cancer, breast cancer is the leading cause of cancer death in women, according to the American Cancer Society. That’s why so many medical professionals encourage women to get mammograms, even though the tests are imperfect at best: only a minority of suspicious mammograms actually leads to a cancer diagnosis.
That results in lots of needless worry for women and their families—not to mention the time, discomfort and expense of additional tests, including ultrasounds and biopsies.

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Seminar: Instrumenting the Human Body

sep22Seminar presentation jointly sponsored by Michigan Technological University’s College of Engineering and the Departments of Biomedical Engineering and Electrical and Computer Engineering
Date: Monday, September 22, 2014; Time: 4:00-5:00 p.m.; Location: M&M U115
Title: Instrumenting the Human Body
Richard B. Brown, Ph.D., Dean of Engineering, University of Utah, Salt Lake City

Abstract: Advances in semiconductor technology are enabling research into, and treatment of, many human diseases. Prof. Brown will present a highly‐integrated, low‐power, wireless, mixed-signal microprocessor that was designed for implantable biomedical applications, and braincomputer interfaces that enable researchers to monitor electrical firing of individual neurons, local field potentials, and chemical signaling in the brain.

Biography: Prof. Brown earned the degrees BS and MS in Electrical Engineering from Brigham Young University. After working in industry for six years, he returned to school at the University of Utah and received the degree PhD in EE in 1985, developing one of the first “smart sensors,” an array of liquid chemical sensors with integrated electronics. Upon graduation, he joined the faculty of the University of Michigan, where he developed their VLSI program and conducted research on circuits (high‐speed, low‐power, high‐temperature, and radiation hard), microprocessors (high‐performance, low‐power, and mixed‐signal), sensors (for ions, heavy metals, and neurotransmitters), and brain‐machine interfaces. At Michigan he held an Arthur F. Thurnau Endowed Professorship. In 2004, he was appointed Dean of the College of Engineering at the University of Utah, where he has continued to do research on circuits, mixed-signal microcontrollers and neural interfaces. Prof. Brown has been a founder with his students of Mobius Microsystems (all‐silicon clock generators), i‐SENS (glucose sensors), Sensicore (water chemistry sensors), and e‐SENS (chemical sensors). He holds 17 patents, has authored more than 225 peer‐reviewed publications, and graduated 30 PhD students.

Richard B. Brown, Ph.D., Dean of Engineering, University of Utah, Salt Lake City presented a seminar at Michigan  Title: Instrumenting the Human Body; Shown here 2nd from left with Michigan Tech faculty, Paul Bergstrom, ECE Chair Daniel Fuhrmann and Saeid Nooshabadi
Richard B. Brown, Ph.D., Dean of Engineering, University of Utah, Salt Lake City presented a seminar at Michigan Title: Instrumenting the Human Body; Shown here 2nd from left with Michigan Tech faculty, Paul Bergstrom, ECE Chair Daniel Fuhrmann and Saeid Nooshabadi

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Seminar: Vascularized Bone Grafts for Craniofacial Regeneration

sep5Biomedical Engineering Graduate Seminar: Warren Grayson, Ph.D. Assistant Professor, Biomedical Engineering, Johns Hopkins University; Friday, September 5 – 138 Fisher at 10:00 a.m.

Title: Vascularized Bone Grafts for Craniofacial Regeneration

The treatment of large bone loss due to congenital defects, trauma or cancer resection remains a huge clini-cal challenge. There are approximately one million fractures requiring bone transplantation annually in the US and it is predicted that within the next 10 years this number will significantly increase, particularly in per-sons over 50 years of age. Tissue engineering provides a viable means of obtaining ‘autologous’ bone grafts for the treatment of large bone defects. Successful application of tissue-engineered grafts however requires that we can couple the formation of de novo vasculature in tandem with new bone growth. Our lab has investigated methods for cultivating anatomically-shaped bone grafts in bioreactors and pre-vascularizing these grafts via co-culture techniques. More recent studies have examined the use of adipose-derived stem cells (ASCs) to engineer vascularized bone grafts that can be used to repair craniofacial de-fects. We have found that heterotypic interaction among endothelial and non-endothelial sub-populations mediate by growth factor effects can choreograph the formation of complex tissue grafts. These findings suggest the tremendous potential for using ASCs in concert with engineering techniques to provide clinically relevant vascularized bone grafts for the repair and regeneration of craniofacial bone loss.

This seminar is partially funded by the Visiting Women & Minority Lecturer/Scholar Series which is funded by the President’s Office and a grant to the Office of Institutional equity from the State of Michigan’s King-Chavez-Parks Initiative

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