Liquid purification or separation – Processes – Liquid/liquid solvent or colloidal extraction or diffusing...
Patent
1996-01-30
1998-04-28
Kim, John
Liquid purification or separation
Processes
Liquid/liquid solvent or colloidal extraction or diffusing...
210643, 210738, 210782, 210790, 210806, 436177, 436178, 530422, 604 4, 604 5, 604 6, B01D 1100, A61M 136
Patent
active
057440387
DESCRIPTION:
BRIEF SUMMARY
This application is a 371 of PCT/AU94/00415 filed Jul. 22, 1994 published as WO95/03840 Feb. 9, 1995.
TECHNICAL FIELD
This invention relates to a plasma delipidation system and in particular relates to a method and apparatus for continuously extracting lipids such as cholesterol from blood plasma of animals including humans.
BACKGROUND ART
Safe and effective methods for reducing covers hyperlipidaemia are of great importance in the treatment of coronary heart disease in humans and other animals. Hyperlipidaemia leads to the formation of atherosclerotic plaques with coronary heart disease being an inevitable result.
Diet is the basic element of all therapy for hyperlipidaemia (excessive amount of fat in plasma). However, the use of diet as a primary mode of therapy requires a major effort on the part of physicians, nutritionists, dietitians and other health professionals.
If dietary modification is unsuccessful, drug therapy is an alternative. Several drugs, used singly or in combination, are available. However, there is no direct evidence that any cholesterol-lowering drug can be safely administered over an extended period.
A combination of both drug and diet may be required to reduce the concentration of plasma lipids. Hypolipidaemic drugs are therefore used as a supplement to dietary control.
Many drugs are effective in reducing blood lipids, but none work in all types of hyperlipoproteinemia and they all have undesirable side-effects. There is no conclusive evidence that hypolipidaemic drugs can cause regression of atherosclerosis.
In view of the above, new approaches have been sought to reduce the amount of lipid in the plasma of homozygotes and that of heterozygotes for whom oral drugs are not effective.
Plasmaphersis (plasma exchange) thereapy has been developed and involved replacement of the patient's plasma with donor plasma or more usually a plasma protein fraction. This treatment can result in complications due to the possible introduction of foreign proteins and transmission of infectious diseases. Further, plasma exchange removes all the plasma proteins as well as very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL).
It is known that HDL is inversely correlated with the severity of coronary arterial lesions as well as with the likelihood that these will progress. Therefore, removal of HDL is not advantageous.
Known techniques also exist which can totally remove LDL from plasma. These techniques include absorption of LDL to heparinagarose beads (affinity chromatography) or the use of immobilised LDL-antibodies. Other methods presently available for the removal of LDL involve cascade filtration absorption to immobilised dextran sulphate and LDL precipitation at low pH in the presence of heparin. Each method specifically removes LDL but not HDL.
LDL aphaeresis has, however, disadvantages. Significant amounts of other plasma proteins are removed during aphaeresis and to obtain a sustained reduction in LDL-cholesterol. LDL aphaeresis must be performed frequently (up to once weekly). Furthermore, LDL removal may be counter productive: low blood LDL levels will result in increased cellular cholesterol synthesis.
To satisfy the need for a method of achieving a reduction in plasma cholesterol, and in particular LDL-cholesterol, in homozygous familial hypercholesterolemia and heterozygous familial hypercholesterolemia patients other than by diet and/or drug thereapy, an extra corporeal lipid elimination process, termed "cholesterol aphaeresis", has been developed. In cholesterol aphaeresis blood is withdrawn from a subject plasma separated from the blood and mixed with a solvent mixture which extracts lipid from the plasma, after which the delipidated plasma is recombined with the blood cells and returned to the subject.
The advantage of this procedure is that LDL and HDL are not removed from the plasma but only cholesterol, some phospholipids and triglycerides are removed. Our earlier U.S. Pat. No. 4,895,558 describes this system.
While cholestero
REFERENCES:
patent: 4235602 (1980-11-01), Meyer et al.
patent: 4258010 (1981-03-01), Rozsa et al.
patent: 4645512 (1987-02-01), Johns
patent: 4668398 (1987-05-01), Silvis
patent: 4680320 (1987-07-01), Uku et al.
patent: 4879037 (1989-11-01), Utzinger
patent: 4895558 (1990-01-01), Cham
patent: 5112956 (1992-05-01), Tang et al.
patent: 5393429 (1995-02-01), Nakayama et al.
Aruba International PTY Ltd.
Kim John
LandOfFree
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