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Degrees:
PhD in Biomedical Engineering
BME News: |
Xiao Lu , Ph.D.
Associate Research Professor,
Biomedical Engineering Department
Contact:
635 Barnhill Drive. MS 2067
Indianapolis, IN 46202
(317) 274-8326
lux@iupui.edu
Education:
Ph.D.
Biomedical Engineering, Chongqing University, China (1996)
Postdoctoral training:
Department of Biomedical Engineering, University of California, Irvine (2002-2004)
Center for Sensory-Motor Interaction, Aalborg University , Denmark (2001-2002)
Institute of Experimental Clinical Research, Aarhus University, Denmark (1997-1999)
Research area: vascular remodeling, coronary circulation, vascular mechanics, mechanotransduction, tissue engineering
Vascular dysfunction is an important aspect of pathogenesis in cardiovascular disease. The mechanical response, structure and molecules present in vascular dysfunction may provide knowledge to understand disease. The mechanical response, including the passive stress-strain (pressure-diameter) relationship and active tone, may provide information on structural remodeling of the vessel wall. The active tone reflects the functional variation of the vessel wall. In our lab, we have created a passive, mechanical two-layer model of an artery (including intimal-medial and adventitial layers) to determine the mechanical properties of coronary arteries. The 3-D constitutive equation of the two-layer model has already been elucidated in the analysis of coronary artery. The active mechanical properties of contraction and relaxation of vessels are analyzed based on an isovolumic method developed in our lab. The active properties reflect the functions of vascular smooth muscle cells and endothelial cells. The mechanical stimulation may have important effects on vascular physiological function and remodeling. Mechanical stimulations in vessels include shear stress of blood flow on endothelium and normal/shear stresses in vessel wall. The mechanical forces may be changed temporally or permanently by exercise, hypertension, hormone, etc. The magnitude, direction, and alterant frequency of the stresses may elicit different responses in vessel wall. The mechanism of mechanotransduction during mechanical stimulation is very interesting in vascular physiology and pathology.
Laboratory research and experimental methodologies
- Vascular remodeling in response to mechanical stimulations
- Animal models by inducing blood flow or pressure overload in arterial or venous system, e.g. arterial venous fistula may increase flow rate in both artery and vein
- Ex vivo simulation - Vascular mechanical properties
- Triaxial device to analysis stress and strain of passive
- Isovolumic technique to analyze the active properties of blood vessels - Mechanotrasduction of endothelial cells
- Cell membrane tension
- Glycoprotein on endothelial cells
Selected Publications:
Kassab GS, Navia JA, Lu X. Proper orientation of the graft artery is important to ensure physiological flow direction. Ann Biomed Eng. 2006 Jun;34(6):953-7. Epub 2006 May 24.
Zhang Y, Lee TS, Kolb EM, Sun K, Lu X, Sladek FM, Kassab GS, Garland T Jr, Shyy JY. AMP-Activated Protein Kinase Is Involved in Endothelial NO Synthase Activation in Response to Shear Stress. Arterioscler Thromb Vasc Biol. 2006 Jun; 26(6):1281-7 Apr 6.
Wang C, Garcia M, Lu X, Lanir Y, Kassab GS. Three-dimensional Mechanical Properties of Porcine Coronary Arteries: A Validated Two-Layer Model. Am J Physiol Heart Circ Physiol. 2006 Sep;291(3):H1200-9. 2006 Mar 31.
Rehal D, Guo X, Lu X, Kassab GS. The Duration of the No-load State affects the Opening Angle of Porcine Coronary Arteries. Am J Physiol Heart Circ Physiol. 2006 May; 290(5): H1871-8. 2005 Dec 9.
Guo X, Lu X, Ren H, Levin E, Kassab GS. Estrogen Modulates the Mechanical Homeostasis of Mouse Arterial Vessels through Nitric Oxide. Am J Physiol Heart Circ Physiol. 2006 May;290(5):H1788-97. Epub 2005 Nov 23.
Pandit A, Lu X, Wang C, Kassab GS. The Biaxial Elastic Material Properties of Porcine Coronary Media and Adventitia. Am J Physiol Heart Circ Physiol. 2005 Jun;288(6):H2581-7.
Lu X, Kassab GS. Nitric oxide is significantly reduced in ex-vivo porcine arteries during reverse flow because of increased superoxide production. J Physiol. 2004 Dec;561(Pt 2):575-582.
Lu X, Pandit A, Kassab GS. Biaxial incremental homeostatic elastic moduli of coronary artery: two-layer model. Am J Physiol Heart Circ Physiol. 2004 Oct; 287(4): H1663-H1669.
Lu X, Yang J, Zhao JB, Gregersen H, Kassab GS. Shear modulus of porcine coronary artery: contributions of media and adventitia. Am J Physiol Heart Circ Physiol. 2003 Nov; 285(5): H1966-H1975.
Lu X, Zhao JB, Wang GR, Gregersen H, Kassab GS. Remodeling of the zero-stress state of femoral arteries in response to flow overload. Am J Physiol Heart Circ Physiol. 2001 Apr; 280(4): H1547-H1559.
Pang Q, Lu X, Gregersen H, Oettingen GV, Astrup J. Biomechanical properties of porcine cerebral bridge veins with reference to the zero-stress state. Journal of Vascular Research. 2001; 38: 83-90.
Zhao JB, Lu X, Zhuang FY, Gregersen H. Biomechanical and morphometric properties of the arterial wall referenced to the zero-stress state in experimental diabetes. Biorheology. 2000; 37(5-6): 385-400.