The experimental group 1) applies different GI animal models to do the basic studies regarding the biomechanical properties and motility of normal and diseased GI tissues, such as diabetes, obstruction and functional diseases; 2) applies and validates the psychophysical and electrophysiological techniques applied on the GI tract of either animals or healthy volunteers. This step explores the mechanistic approach of the different sensory models. When the models have been proved to be robust they are applied in clinical or pharmaceutical research; and 3) applies the histological and immunohistochemical methods to explore the mechanisms of the biomechanical remodelling of GI tract in different diseases.
Previous studies:
The team has done many studies
Biomechanical properties of normal GI tissues
Histomorphometry and biomechanical remodelling of GI tissues during growth and in different situations, such as fasting, intestinal resection, inflammations, diabetes, obstruction, and so on.
Biomechanical experiments using delicate torsion machine with normal and diabetes rat (3; 4)
Zero-stress state of one, two and three layered esophagus
Effect of drugs on zero-stress state of diabetic intestine
Mechano-sensory function of normal and obstructed intestine
AGE and RAGE expression in normal and type-1 diabetic GI tissues
Ongoing researches:
Smooth muscle dysfunction of obstructed intestine and diabetic small intestine
Biomechanical properties of GI tissues in functional diseases
Mechano-sensory function of type-1 and type-2 diabetic intestine
AGE and RAGE expression in normal and type-2 diabetic GI tissues
Effect of Chinese herbs on the biomechanical properties of GI tissues in functional diseases, such as IBS and functional dyspepsia
Multi- model stimulations (thermo, electric, chemical, drug), longitudinal force
Human nerve studies
Staff: The staff working in the experimental group consists of associate professor, post-doc and PhD students.
Main technology used: 1) Pressure-video recording system; 2) Tri-axial torsion machine; 3) Mechano-sensory recording system; 4) Histological and immunohistological techniques
Collaborators
1) Other teams in mech-sense; 2) La Jolla Bioengineering Institute; 3) China-Japan Friendship Hospital; 4) Grundy D: Department of Biomedical Science The University of Sheffield; 5) Nakaguchi T: Graduate School & Faculty of Engineering Chiba University; 6) College of Bioengineering, Chongqing University
Selected publications:
Zhao J, Chen X, Yang J, Liao D, Gregersen H. Opening angle and residual strain in a three-layered model of pig oesophagus. J Biomech. 2007; 40 (14): 3187-92.
Zhao J, Liao D, Gregersen H. Tension and stress in the rat and rabbit stomach are location- and direction-dependent. Neurogastroenterol Motil. 2005; 17(3): 388-98.
Zhao J, Yang J, Gregersen H. Biomechanical and morphometric intestinal remodelling during experimental diabetes in rats. Diabetologia. 2003; 46(12): 1688-97.
Yang J, Grundy D, Kunwald P, Zhao J, Nakaguchi T, Jiang W, and Gregersen H. Rat mesenteric afferent nerve response to mechanical stimuli. Neurogastroenterology and motility 2008. 8-11-0008. Ref Type: Conference Proceeding
Yang J, Liao D, Zhao J and Gregersen H. Shear modulus of elasticity of the esophagus. Ann Biomed Eng 32: 1223-1230, 2004.
Yang J, Zhao J, Liao D and Gregersen H. Biomechanical properties of the layered oesophagus and its remodelling in experimental type-1 diabetes. J Biomech 39: 894-904, 2006.
Yang J, Zhao J, Zeng Y and Gregersen H. Biomechanical properties of the rat oesophagus in experimental type-1 diabetes. Neurogastroenterol Motil 16: 195-203, 2004.
Storkholm JH, Zhao J, Villadsen GE, Hager H, Jensen SL, Gregersen H. Biomechanical remodeling of the chronically obstructed Guinea pig small intestine. Dig Dis Sci. 2007; 52(2): 336-46.
