ISSN:0733-2459    

DOI:10.1002/jca.2920040202

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe major life‐threatening events in advanced atherosclerosis are precipitated by the plaque. Thrombosis in the muscular arteries and rupture of the large elastic arteries usually follows rupture of the plaque's fibrous cap.The smooth muscle cell (SMC) participates in many aspects of the atherosclerotic process: lipid uptake, synthesis of plaque components, and cell proliferation. The latter is a particularly significant aspect of the disease.High serum cholesterol levels stimulate proliferation of arterial medial cells; low‐density lipoproteins (LDL) from hypetiipidemic plaques induce ingress and storage of cholesterol ester. These effects are inhibited by high‐denisty lipoproteins (HDL). Endothelial injury may be an important part of the patnogenesis of some atherosclerotic plaques because powerful growth factors actively stimulate SMC proliferation, even when other risk factors are absent.Utilization of animal models of atherosclerosis, especially nonhuman primate models, has led to great progress in understanding this disease process. In controlled feeding experiments, severe atherosclerosis has been produced in rhesus monkeys by means of a high fat, high cholesterol diet. Animals then placed on a tow fat, low cholesterol diet, or given cholestyramine, or a combination of these two approaches, showed a remarkable decrease in the size of their atherosclerotic plaques.Many cpidemologic studies, as well as more recent prospective intervention studies involving bile acid sequestrants, indicate by imaging techniques that plaque regression takes place in h

ISSN:0733-2459    

DOI:10.1002/jca.2920040203

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0733-2459    

DOI:10.1002/jca.2920040204

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractDextran sulfate (Mr 5,000) was covalently linked to porous cellulose beads, and the dissociation constant (Kd) and the maximum binding level (S) of the beads were calculated for the human plasma lipoproteins VLDL, LDL, and HDL. The S values for VLDL and LDL were 2 and 7 g cholesterol/liter of the wet beads and that for HDL was almost negligible, although the apparent Kdwere all in the same order. In fact, LDL and VLDL were exclusively adsorbed by the beads from human plasma in vitro. Bound LDL was desorbed with 0.35 M Nacl. The beads were packed in a column (25‐ml) and used with polysulfone hollow fibers in experimental LDL‐apheresis for WHHL rabbits; LDL cholesterol was reduced from 500 to 200 mg/dl, while HDL, total plasma protein, and major blood cell counts did not change.For LDL apheresis of familial hypercholesterolemia, the sorbent column, 400‐ml, was used with the polysulfone hollow fiber filter. The maximum removal of LDL + VLDL cholesterol was 6 to 8 g with a single column resulting in its reduction by 250 to 300 mg/dl after 3.5 liters plasma treatment. Adsorption was negligible with albumin, HDL, IgA, G, M, apoA‐I, A‐II, C‐II, enzymes, and electrolytes. Activated complement fragments, C3a, and Csa, were completely adsorbed. By periodic removal of LDL, an increase of HDL cholesterol was observed in some cases. In order to increase LDL removal in a single treatment and to reduce the extracorporeal circulation volume, two small columns (150 ml each) were used alternatively. The column saturated with LDL was washed with 0.7 M NaCl for regeneration while the other column was used. LDL + VLDL cholesterol decreased linearly to the treated plasma volume in semilogarithmic plot, showing that the LDL removal was optimized in

ISSN:0733-2459    

DOI:10.1002/jca.2920040205

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractAn on‐line continuous system for the selective precipitation of low‐density lipoproteins (LDL) and very low‐density lipoproteins (VLDL) has been devised and tested. This system conserves high‐density lipoproteins (HDL) and other plasma macromolecules. LDL and VLDL are precipitated from plasma using 10–35 mg/dl dextran sulfate (Mr5,000) in the presence of 55 mM calcium with a reduced concentration of monovalent cations. The plasma is obtained by membrane filtration of whole Wood using the COBE Gentryr̀ TPE System (Cobe Laboratories Inc, Lakewood, Co.). The precipitated LDL plus VLDL is removed by filtration, and the electrolytes are restored by dialysis. The plasma minus LDL plus VLDL is then returned to the patient.Four patients with heterozygous familial hypercholesterolemia (type II) were treated 70 times. The mean pretreatment serum cholesterol was 383 mg/dl. The mean reductions in plasma components were: LDL plus VLDL 63%; HDL 27%; fibrinogen 19%; albumin 15%; IgG 20%; IgA 19%; IgM 25%; C3 30%; and C4 27%. The cholesterol returned to near normal values in approximately 2 weeks after each treatment.Four normal volunteers were each treated one time. These individuals had a mean pretreatment serum cholesterol of 201 mg/dl. The mean reduction in plasma components were: LDL plus VLDL 70%; HDL 27%; fibrinogen 24%; albumin 14%; IgG 18%; IgA 17%; IgM 20%; C3 27%; C4 22%; C3 proactivator 12%; alpha1‐antitrypsin 17%; ceruloplasma 17%; transferin 18%; alpha2‐macroglobulin 17%; and orosomucoid 13%.It is our conclusion that dextran sulfate precipitation is an effective on‐line means of selectively removing LDL plus VLDL from plasma while conserving HDL and other plasma macromolecules. The capacity of the system is limited only to the size of the filter (currently estimated at over 30 gm of cholesterol). The reduction of LDL plus VLDL is limited only by the quantity of plasma processed while the reduction in the other plasma components is virtually independent of plasma

ISSN:0733-2459    

DOI:10.1002/jca.2920040206

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe clinical application of a new extracorporeal procedure (HELP) for the selective elimination of low‐density lipoproteins and fibrinogen by heparin precipitation at acid pH is described. Plasma, obtained by filtration of whole blood through a 0.2 μm filter is continuously mixed with an equal volume of an acetate buffer (pH 4.85) containing heparin. After removal of the precipitated heparin complex by filtration, excess heparin is adsorbed to a specially developed filter, and the dear plasma filtrate is subject to bicarbonate dialysis/ultrafiltraiion to restore physiologic pH and remove excess fluid. The calculated efficiency for the elimination of low‐density lipoproteins and fibrinogen from plasma by HELP is 100% and is therefore comparable to conventional plasmapheresis. However, the HELP system shows a high degree of specificity, with over 80% of total protein being returned to the patient. A total of over 350 treatment procedures have now been performed. Patient compliance and acceptance have been excellent, and no major complications have been observed. The system is therefore suitable for the treatment of severe hyper‐β‐lipoproteinemia; its use for the treatment of coronary heart disease is currently under investigation in a prospective multicenter study in which treatment efficiency will be controlled by coronary angiography on 45 patients treated with HELP over a period o

ISSN:0733-2459    

DOI:10.1002/jca.2920040207

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0733-2459    

DOI:10.1002/jca.2920040208

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0733-2459    

DOI:10.1002/jca.2920040209

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

ISSN:0733-2459    

DOI:10.1002/jca.2920040210

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe PCS is an automated centrifugal system designed for rapid collection of platelet poor plasma (PPP) for source or fresh frozen uses, or platelet concentrate and PPP. The microprocessor‐controlled system increases plasma collection efficiency through improved plasma yields, increased donor safety, and operation of multiple machines per operator.600 ml of plasma can be collected in an average of 35 minutes per procedure with greater than 50,000 collections by U.S. commercial organizations. PCS plasma yields 10% greater Factor VIII recovery through fractionation when compared to manually‐collected plasma based upon multiple studies throughout the world. Collection of PRP is an efficient, reliable, safe, and cost‐effective method for processing plasma and the only system available for combined platelet and plasma procur

ISSN:0733-2459    

DOI:10.1002/jca.2920040211

出版商:John Wiley&Sons, Inc.    

年代:1988

数据来源: WILEY