Ijad Madisch

Home Institutions
Medizinische Hochschule Hannover
Universität Hannover, Informatik

Host Institution
Massachusetts General Hospital, CIMIT, Department of Radiology, Harvard Medical School

E-Mail:
 I.Madisch@gmx.de

Research Topic
see Abstract
Personal Reactions to the U.S. Experience
1.) It is the fourth time that I have visited the USA, but this visit was the first after 9/11. I was a bit afraid of being there as a German of Syrian origin. However, I realized that the people in Boston don't care about your nationality, because Boston is a "big salad" of people from so many different countries. It was easier than I thought to discuss with the people different politician topics. Boston is a very nice and historic city with so many people from different countries. However, it was very hard to get to know to people, especially American people. Under "getting to know people" I understand more than only "Hello, how are you?"! The first 2 months were the hardest: I had to face so many problems, such as understanding the English (see below), organising various things, and getting started with the projects. After a while I got used to many things, so the life is getting easier. I started playing soccer on an American team, found friends for different activities (squash), and going out. The soccer was the funniest.
2.) My advisor and most of the people in my laboratory were very nice, in spite of some people who see me as a competitor. I was lucky that I have had 3 months ago a very good introduction to my work by Dr. med. Soenke Bartling, a BMEP alumnus. In addition, my advisor tried to make life as easy as possible for me. One big advantage was that my advisor had studied Computer Science and Medicine, too. He could give to me good advice and explanations, both in Computer Science and Medicine. I would describe the differences between Germany and the USA not only based on the money for research, which you have here at the Harvard University. The main difference is that here they acknowledged your skills, and they tried to use my knowledge in Computer Science and Medicine in the best possible way. I had the opportunity to see and understand the overlap between Medicine and Computer Science. This made it very easy to see the effective possibilities of combining Computer Science and Medicine.
Most humorous incident
 1.) I arrived at the airport of Boston, and like everybody, I had an interview. The man's first question was, "Where are you from?" I said, "Germany". "You don't look like a German," he said.
2.) After 1 hour exploring the Harvard Library and asking so many people how to find an Image Processing Book, a student explained that Computer Science books are the Astrophysics Center. After this I was so hungry that, before trying to find the Astrophysics Center, I went to a pizza place. I wanted two slices of cheese pizza, but I made a mistake in ordering because I was so confused, due to the crowd of people around me. "I want 2 subs with cheese," I said. Then he asked me several times, whether I really want only cheese on my sub. I was annoyed and didn't understand why he was asking so many times and I repeated every time "Yes only with cheese!" He was preparing a sub with only cheese and I was thinking, "Hmm, who the hell is eating this "baguette?" Then I realised that I had made a mistake, but I didn't say anything, because it was so embarrassing. He gave to me the 2 subs and I said," Yeah, thanks that's exactly what I want to have." Afterwards I also bought a Coke to make the eating easier.

Helpful Hints for Future Students

  • Open a bank account at Fleet Bank (free for students).
  • Get access to the Harvard Library (if you are in Boston, Cambridge).
  • Try to get a J1- Visa, this facilitate a lot.
  • Go to the Outlets in Wrentham or Kittery.
  • Play soccer at the BSSC in Newton.

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Abstract on Research Topic
Correlation for VCT imaging and biomechanical compression and protein transcription analysis of tissue engineered bone in vitro and in vivo

Authors:
Ijad Madisch, Christian Weinand, Rajiv Gupta, Jens Hainmueller, Joseph P. Vacanti, Thomas J. Brady

Institution:
Massachusetts General Hospital, CIMIT, Department of Radiology, Harvard Medical School

Introduction:
Volumetric CT imaging is a new ultra-high resolution imaging technique that could be suitable to demonstrate new bone formation. We evaluated the value of this new exciting technique for tissue-engineered bone in standardized samples in vitro and in vivo.

Material and Methods:
2x2x0.7cm scaffolds with hydrogels (Collagen I, fibrin, alginate and Pluronic F 127) and embedded differentiated mesenchymal stem cells were cultured under two different dynamic culture conditions for 6 weeks to tissue engineer bone. At six weeks the constructs were examined histologically, radiologically (VCT scanner), biomechanically (unconstrained uniaxial compression) and analyzed for bone specific protein transcription.
The same construct compositions were implanted subcutaneously in nude mice for 1, 2, 4, and 6 weeks. All constructs were examined at these time points histologically, radiologically (VCT scanner), biomechanically (unconstrained uniaxial compression) and for protein transcription to analyze for bone specific proteins.
The VCT scanner effective field of view was 25x25x18cm, with isotropic resolution of ~200m with 2x2 binning, and volumetric coverage. In a 360 deg rotation, 580 projections were acquired with tube voltage of 80kV and tube current of 10mA. The projection data was reconstructed using a modified Feldkamp algorithm. For all sample results, we calculated the correlation between the Hounsfield values for each specific sample with the resultant biomechanical strength and protein transcription levels, using the Pearson, Kendall and the Spearman correlation coefficients. Results: The VCT permit accurate detection of the newly formed cells. Density and size could be evaluated. The results of the invitro samples were congruent in overall structure to the invivo samples. For the in vitro samples we found that higher density generally increased the robustness of the scaffolds, as evidenced by a high correlation of around 0.57-0.61. This correlation was very robust across the different correlation coefficients we computed (Spearman, Pearson, Kendall, N=8). In addition a high correlation between the density (Hounsfield Units) and protein transcription was found (0.87-0.95).

Conclusions:
Volumetric CT scanning is a reliable method to detect the new formation of bone in vitro and in vivo, the imaging results are concordant with biomechanical findings and results in protein transcription analysis.