Chemistry: molecular biology and microbiology – Apparatus – Differentiated tissue perfusion or preservation apparatus
Patent
1994-04-18
1996-12-10
Redding, David A.
Chemistry: molecular biology and microbiology
Apparatus
Differentiated tissue perfusion or preservation apparatus
4352865, 4352883, 4352887, 435808, 422104, C12M 300
Patent
active
055830439
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a cover slip holder as described in the preamble of claim 1, for simulation of in vivo blood flow conditions in occluded blood vessels. The invention also relates to the accompanying parallel-plate perfusion chamber including the cover slip holder. One preferred embodiment of the perfusion chamber is when it is connected to a mixing device for mixing in vitro added solutions to the blood flow before reaching the parallel-plate perfusion chamber.
The cover slip holder according to the present invention is inserted in a parallel-plate perfusion chamber, so that the bottom of the knob creates the roof/floor of a measure chamber and in the bottom of the knob a varying number of glass slides or cover slips, made of plastic or glass or any other material, are attached in specially made grooves. These cover slips can/cannot be covered with a biological/synthetic material, and the surface levels of the cover slips vary in relation to each other and to the roof/floor of the measure chamber, to produce a varying unilateral constriction of the cross-sectional area of the flow slit. Bilateral constriction of the flow cross-sectional area can, in a special embodiment, be obtained by elevating an area of the bottom of the measure chamber, facing the cover slips of the cover slip holder. Minimum 20 mm upstream of the blood flow inlet of the parallel-plate perfusion chamber, preferably a mixing device functioning according to the venturi-principle, can be installed in the flow channel. A device in which blood is exposed to materials facilitating thrombogenesis under conditions simulating blood flow in human blood vessels is beneficial both for research and industry in the medical field. By puncturing a human vein, inserting a venous catheter which is connected, by plastic tubes, with a parallel-plate perfusion chamber, and a pump, located downstream to the parallel-plate perfusion chamber, it is possible to maintain ex vivo (i.e. anti-coagulation is not used) blood flow through a perfusion chamber. In this connection, an annular perfusion chamber has previously been constructed, in which flowing blood was brought in close contact with human subendothelium, digested with .alpha.a-chymotrypsin which produced a surface which was rich in collagenous fibrils (Baumgartner, H. R., Microvasc. Res. 5: 167, 1973). Collagenous fibrils are shown to be active in promoting aggregation of platelets in flowing blood (Baumgartner, H. R., Thromb. Haemost. 37: 1, 1977). More recently, perfusion chambers with rectangular cross-section of the blood flow slit have been constructed, in which a commercially available glass slide or plastic cover slip is attached in a specially made groove, located 90.degree. on the flow direction. This glass slide or plastic cover slip, which surface is on the same level as that of the roof of the chamber, was covered by biological material (endothelial cells, connective tissue from endothelial cells and collagen) to promote thrombogenesis (Sakariassen, K. S., Aarts, P. A.M. M., de Groot, P. G., Houdijk, W. P.M., Sixma, J. J. J. Lab. Clin. Med. 102: 522, 1983). This perfusion chamber has a flow channel, in which the cross-section is changed from circular in the supply tubing to rectangular in the measure chamber and back to circular, usually accompanied by changed cross-sectional area. Such changes can lead to labile flow conditions or flow separation in the measure chamber. The perfusion chamber was therefore modified such that the transition from circular to rectangular dimensions of the flow channel was smooth. It was calculated that the reduction of the pressure gradient in this system, owing to the lesser kinetic energy, was less than 5% of the acting viscous force. This indicates laminar flow condition in the perfusion chamber (Sakariassen, K. S., Joss, R., Muggli, R., Kuhn, H., Tschopp, T. B., Sage, H., Baumgartner, H. R., Arteriosclerosis, 10: 276-284, 1990) .
The mentioned modified perfusion chamber makes possible an ex vivo test system for simulation of in vivo blood flow condi
REFERENCES:
patent: 5278048 (1994-01-01), Parce et al.
Sakariassen, Arteriosclerosis, vol. 10, No. 2, 1990.
Hantgan, et al, Blood, vol. 76, No. 21, Jul. 1990.
Sakariassen, J. of Lab. and Clin. Medicine, vol. 102, No. 4, Oct., 1983.
R. M. Barstad, et al., A Perfusion Chamber Developed to Investigate Thrombus Formatin and Shear Profiles in Flowing Native Human Blood at the Apex of Well-Defined Stenoses, Arteriosclerosis and Thrombosis, vol. 14, No. 12, Dec. 1994, pp. 1984-1991.
Hafslund Nycomed As
Redding David A.
LandOfFree
Cover slip holder for bilateral and unilateral simulation of thr does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Cover slip holder for bilateral and unilateral simulation of thr, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cover slip holder for bilateral and unilateral simulation of thr will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-423673