Wireless Impedance Monitoring

Working with Dr. S. Tang (UTSW Internal Medicine), Dr. S. J. Spechler (UTSW Internal Medicine) and Dr. J. C. Chiao (UT Arlington Electrical Engineering) and graduate students at UTA, implantable wireless capsules have been developed to measure pH, dissolved solids (as impedance) and other parameters in the esophagus.  Work to continue and expand the applications of the modules is on-going¹.

¹ An Implantable, Wireless and Batteryless Impedance Sensor Capsule for Detecting Acidic and Non-Acidic Reflux,” Thermpon Ativanichayaphong, Shou Jiang Tang,, Jianqun Wang, Wen-Ding Huang, Harry F. Tibbals, Stuart J. Spechler, J.-C. Chiao, Gastroenterology, No. 134, (suppl.):A-63, 2008. 

Tissue Dynamics and Mechanics

Using piezoelectric, acoustic, and electromagnetic transducers, as well as precision electromechanical stress measurement instruments, Bioinstrumentation staff have assisted in design and performance of a number of studies of bone, tendon, muscle and connective tissue mechanical properties.  These include theoretical calculations of interactions between electromagnetic stimulation and metal implants in bone, measurement of strength of bone healing, adhesions in the abdominal cavity, and determination of optimal placement for sutures. ²

²  Biomechanical properties of the vaginal wall: effect of pregnancy, elastic fiber deficiency, and pelvic organ prolapse, Rahn, DD, Ruff, MD, Brown, SA, Tibbals, HF, Word, RA, Am J Obstet Gynecol. 2008, vol 198, No 5 p 590.e1-6

Electrophysiology Stimulation and Monitoring

Working with students from the Biomedical Engineering program and faculty at UT Southwestern, UT Arlington and UT Dallas, computer interface systems using LabView have been developed to control and record patterns of electrical and chemical stimulation simultaneously in multiple experimental muscle samples.  The LabView systems have been developed for smooth muscle, skeletal muscle, uterine³, bladder and heart muscle, and for other types of complex stimulation and feedback monitoring experiments using cell cultures, explants, live animal subjects, and human subjects.  The systems facilitate planning of experiments, accurate recording and reproduction of experimental protocols, precise control of experimental conditions, and productivity in gathering, organizing, and analyzing results.  Supported faculty and collaborators include: Dr. Roy Chaney (UTD), Dr. R. A. Word (UTSW ObGyn), Dr. K. E. Kamm (UTSW Physiology), Dr. B. Adinoff (UTSW Psychiatry), and others.

³ Effect of periurethral denervation on function of the female urethra, C.Y Wai, P Liehr, H.F Tibbals, M Sager, J.I Schaffer, R.A Word, American Journal of Obstetrics & Gynecology, Volume 189, 1517-1884 (2003).

Animal Behavior Monitoring Chamber

With Dr. Howard Gershenfeld, Psychiatry, Integrative Biology

This chamber was originally designed by the National Institutes of Health and was validated as a paradigm for testing the anxiety level in mice.⁴  The chamber is divided into two sections: a light side and a dark side. A single mouse is placed in the light side of the chamber. The assumption is that if the mouse has a high level of anxiety, it will move quickly from the light to dark side of the chamber to escape the bright light. The motility of the mouse can also be used as an indicator of anxiety level and can be measured by counting the number of times the mouse makes a transition from one side of the chamber to the other. The time it takes for the mouse to make the first light to dark transition and the total number of transitions made during a specified time are recorded. These can then be analyzed to determine anxiety levels. 
The previous design used a microprocessor to control each animal monitoring chamber. The results were displayed at the end of the run and had to be recorded manually for future analysis. Our new design takes advantage of desk-top PCs for data acquisition and storage. Each PC can run up to four Animal Behavior Monitoring Chambers concurrently. Data are stored on the hard disk of the PC, alleviating the need for manual recording of experimental results. Now the researcher can run several trial at once, and the results are recorded automatically and are ready for analysis in a spreadsheet of the user's choosing. 

⁴ Crawley, J. and Goodwin, F. K. Preliminary Report of a Simple Animal Behavior Model for the Anxiolytic Effects of Benzodiazepines. Pharmacology Biochemistry & Behavior, Vol. 13, pp 167-170. 1980.