| For medical practitioners and the general public - Cholesterol Journal Article Catalog. |
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| One-eyed animals implicate cholesterol in development Strauss, E. (1998), Science 280(5369): 1528-9. |
| One-sided action of amphotericin B on cholesterol-containing membranes is determined by its self-association in the medium Bolard, J., P. Legrand, et al. (1991), Biochemistry 30(23): 5707-15. Abstract: The inducement of K+ permeability through membranes by the polyene antibiotic amphotericin B (AmB) has been analyzed as a measure of the antibiotic activity. Dose-response curves have been obtained with cholesterol- and ergosterol-containing egg yolk phosphatidylcholine large unilamellar vesicles (LUVs), human erythrocytes, and Saccharomyces cerevisiae cells. Conductance changes induced by AmB in sterol-containing planar bilayer membranes have also been studied. AmB self-association in aqueous buffer was determined by circular dichroism (CD) as a function of the antibiotic concentration. Electronic absorption and CD spectra of AmB were recorded in the presence of LUVs. For given AmB concentrations, the extent of permeability inducement is dependent on the lipid concentration. On the other hand, for cholesterol-containing LUVs or erythrocytes, a critical AmB concentration had to be reached before any permeability is observed. Independent of lipid concentration, this concentration was directly related to antibiotic self-association in the aqueous buffer. The same observation was made for erythrocytes and nystatin. The AmB absorption and CD spectra were totally different for ergosterol- and cholesterol-containing LUVs. Formation of single channels by one-sided addition of AmB could be observed only in ergosterol-containing membranes. These data lead us to propose that the permeability pathways induced by amphotericin B or nystatin, in ergosterol- and in cholesterol-containing membranes, are of different natures. In the latter case the antibiotics are only active, by single-sided addition, in the self-associated form. These findings offer important clues for the design of less toxic derivatives of AmB: they should have a low degree of self-association in water. |
| One-year treatment with ethyl esters of n-3 fatty acids in patients with hypertriglyceridemia and glucose intolerance: reduced triglyceridemia, total cholesterol and increased HDL-C without glycemic alterations Sirtori, C. R., G. Crepaldi, et al. (1998), Atherosclerosis 137(2): 419-27. Abstract: n-3 Fatty acids in the form of ethyl esters (EE) allow lower daily doses and improved compliance. Administration of n-3 fatty acids to patients with glucose intolerance has led to controversial findings, some studies indicating worsening of the disorder, others no effect, or an improvement. A total of 935 patients with hypertriglyceridemia, associated with additional cardiovascular risk factors, i.e. glucose intolerance, NIDDM and/or arterial hypertension were entered a double blind (DB) protocol lasting 6 months with n-3 EE versus placebo, followed by a further 6 months of open study (n = 868) on 2 g a day of n-3 EE. At the end of the DB period, triglyceridemia in the total group was reduced significantly more by n-3 EE, without alterations in glycemic parameters. In the 6 months open follow up, patients on n-3 EE with type IIB hyperlipoproteinemia showed a significant reduction of total cholesterol, both in cases with (-4.15% vs. the 6 month levels) and without NIDDM (-3.8%). HDL-cholesterol had an overall mean rise of 7.4%, maximal in type IV patients with (+9.1%) and without (+10.1%) NIDDM. No alterations in glycemic parameters were detected in treated patients. Administration of n-3 EE to patients with hypertriglyceridemia associated with NIDDM or impaired glucose tolerance appears safe and effective. |
| On-line detection of cholesterol and calcification by catheter based Raman spectroscopy in human atherosclerotic plaque ex vivo van de Poll, S. W., K. Kastelijn, et al. (2003), Heart 89(9): 1078-82. Abstract: BACKGROUND: Raman spectroscopy has the unique potential to detect and quantify cholesterol and calcification in an atherosclerotic plaque in vivo. OBJECTIVE: To evaluate the sensitivity and specificity of this technique for detecting cholesterol or calcification in human coronary artery and aorta specimens ex vivo, using a compact clinical fibreoptic based Raman system developed for in vivo applications. DESIGN: From nine coronary arteries and four aorta specimens, 114 sites were evaluated for the presence of cholesterol and calcification by Raman spectroscopy and standard histology. Raman spectra were acquired and evaluated on-line in around five seconds. RESULTS: The correlation between Raman spectroscopy and histology was r = 0.68 for cholesterol and r = 0.71 calcification in the plaque (p < 0.0001). Sensitivity and specificity for detecting cholesterol and calcification were excellent: receiver operating characteristic (ROC) analysis for each of the components revealed areas under the curves of > 0.92 (p < 0.0001). At the optimal cut-off values determined by ROC analysis, positive predictive values of > 80% and negative predictive values of > 90% were obtained. CONCLUSIONS: On-line real time catheter based Raman spectroscopy detects accumulation of cholesterol and calcification in atherosclerotic plaque with high sensitivity and specificity. |
| Only one of four patients with familial hypercholesterolaemia reach cholesterol treatment goals in primary prevention Hollman, G., A. C. Ek, et al. (2004), J Intern Med 256(2): 176-7. |
| Ontogenesis and regulation of cholesterol metabolism in the central nervous system of the mouse Quan, G., C. Xie, et al. (2003), Brain Res Dev Brain Res 146(1-2): 87-98. Abstract: These studies characterized the ontogenesis and regulation of cholesterol turnover in the central nervous system (CNS) of mice. During the first 3 weeks after birth, the CNS grew rapidly and equaled 5% of body weight. The cholesterol pool in this tissue expanded at a rate of 0.26 mg/day and the CNS synthesized sterol at a rate of 0.28 mg/day. In mature mice between 13 and 26 weeks of age, there was a marked decrease in these parameters including a reduction in the relative size of the CNS to 1.7% of body weight, a decrease in the rate of sterol accretion to 0.012 mg/day, and a reduction in the rate of cholesterol synthesis to 0.035 mg/day. Deletion of the NPC1 and CYP46A1 proteins markedly altered cholesterol metabolism in the CNS. However, changes in the plasma cholesterol concentration or loss of function of ATP-binding cassette AI transporter (ABCA1), scavenger receptor class B, type I (SR-BI), low-density lipoprotein receptor (LDLR), APOE or APOAI had no effect on sterol turnover in the brain. Thus, during early development, cholesterol comes entirely from local synthesis. In the adult, however, synthesis exceeds the need for structural cholesterol so that there is a constant excretion of sterol from the CNS into the plasma at a rate of about 0.023 mg/day. |
| Ontogeny of acyl-CoA: cholesterol acyltransferase in rat liver, intestine, and adipose tissue Little, M. T. and P. Hahn (1992), Am J Physiol 262(4 Pt 1): G599-602. Abstract: The development of acyl-coenzyme A: cholesterol acyltransferase (ACAT), was determined in the rat liver, intestine, and white (WAT) and brown adipose tissue (BAT). Animal studies have shown that dietary manipulation of cholesterol metabolism during an animal's early development can have persistent and permanent effects. Therefore it is important that the ontogeny of ACAT, one of the key enzymes in cholesterol metabolism, be clearly established. White Wistar rats were killed on day 21 of gestation, at birth, and on postnatal days 10, 14, 18, 21, 22, 25, 30, and 60. The tissues were rapidly excised, microsomes were prepared, and the activity of ACAT was measured as the rate of incorporation of 1-14Coleoyl coenzyme A into cholesterol esters. Age-specific changes were observed in three of the four tissues investigated. Rat liver and intestine possess significant amounts of ACAT activity throughout development with marked variations in activity during this time. ACAT activity in BAT is low and variable throughout development with the exception of high activity noted in the adult animal. WAT contained little or no ACAT activity during development. |
| Opposing effects of reactive oxygen species and cholesterol on endothelial nitric oxide synthase and endothelial cell caveolae Peterson, T. E., V. Poppa, et al. (1999), Circ Res 85(1): 29-37. Abstract: Synthesis of nitric oxide (NO) by endothelial nitric oxide synthase (eNOS) is critical for normal vascular homeostasis. eNOS function is rapidly regulated by agonists and blood flow and chronically by factors that regulate mRNA stability and gene transcription. Recently, localization of eNOS to specialized plasma membrane invaginations termed caveolae has been proposed to be required for maximal eNOS activity. Because caveolae are highly enriched in cholesterol, and hypercholesterolemia is associated with increased NO production, we first studied the effects of cholesterol loading on eNOS localization and NO production in cultured bovine aortic endothelial cells (BAECs). Caveolae-enriched fractions were prepared by OptiPrep gradient density centrifugation. Treatment of BAECs with 30 microgram/mL cholesterol for 24 hours stimulated significant increases in total eNOS protein expression (1.50-fold), eNOS associated with caveolae-enriched membranes (2.23-fold), and calcium ionophore-stimulated NO production (1.56-fold). Because reactive oxygen species (ROS) contribute to endothelial dysfunction in hypercholesterolemia, we next studied the effects of ROS on eNOS localization and caveolae number. Treatment of BAECs for 24 hours with 1 micromol/L LY83583, a superoxide-generating napthoquinolinedione, decreased caveolae number measured by electron microscopy and prevented the cholesterol-mediated increases in eNOS expression. In vitro exposure of caveolae-enriched membranes to ROS (xanthine plus xanthine oxidase) dissociated caveolin more readily than eNOS from the membranes. These results show that cholesterol treatment increases eNOS expression, whereas ROS treatment decreases eNOS expression and the association of eNOS with caveolin in caveolae-enriched membranes. Our data suggest that oxidative stress modulates endothelial function by regulating caveolae formation, eNOS expression, and eNOS-caveolin interactions. |
| Opposite effects of plasma from human apolipoprotein A-II transgenic mice on cholesterol efflux from J774 macrophages and Fu5AH hepatoma cells Fournier, N., A. Cogny, et al. (2002), Arterioscler Thromb Vasc Biol 22(4): 638-43. Abstract: Overexpression of human apolipoprotein A-II (hapo A-II) in transgenic mice (hAIItg mice) induced marked hypertriglyceridemia and low levels of plasma high density lipoprotein (HDL) with a high hapo A-II content. We sought to determine whether cholesterol efflux to plasma and HDL from these mice would be affected. In the Fu5AH cell system, plasma from hAIItg mice induced a markedly lower cholesterol efflux than did control plasma, in accordance with the dependence of efflux on HDL concentration. Moreover, HDLs from hAIItg mice were less effective acceptors than were control HDLs. In the J774 macrophage cell system, pretreatment with cAMP, which upregulates ATP binding cassette transporter 1, induced a marked increase in the efflux to hAIItg plasma as well as to purified hapo A-I and hapo A-II, whereas it had no effect on cholesterol efflux to control plasma. A strong positive correlation was established between percent cAMP stimulation of efflux and plasma hapo A-II concentration. The cAMP stimulation of efflux to hAIItg mouse plasma may be linked to the presence of pre-beta migrating HDL containing hapo A-II. Thus, despite lower HDL and apolipoprotein A-I contents, the increased ability of plasma from hAIItg mice to extract cholesterol from macrophage-like cells may have an antiatherogenic influence. |
| Opposite effects on cholesterol metabolism and their mechanisms induced by dietary oleic acid and palmitic acid in hamsters Kurushima, H., K. Hayashi, et al. (1995), Biochim Biophys Acta 1258(3): 251-6. Abstract: The effects of dietary oleic acid on cholesterol metabolism were investigated and compared with those of palmitic acid in hamsters. Addition of 5% oleic acid to a 0.1% cholesterol-supplemented diet decreased plasma total cholesterol, very low density lipoprotein (VLDL) cholesterol, and low density lipoprotein (LDL) cholesterol, increased hepatic LDL receptor activity, and decreased plasma cholesteryl ester transfer protein (CETP) activity in comparison with 0.1% cholesterol alone. In contrast, addition of 5% palmitic acid to a 0.1% cholesterol-supplemented diet increased total cholesterol and LDL-cholesterol, increased plasma CETP activity, and suppressed hepatic LDL receptor activity to a greater extent than 0.1% cholesterol alone. Neither oleic acid nor palmitic acid altered hepatic microsomal 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity, but oleic acid increased hepatic microsomal cholesterol 7 alpha-hydroxylase activity. These results suggest that dietary oleic acid inhibits the increases in total, VLDL-, and LDL-cholesterol induced by dietary cholesterol by preventing both LDL receptor suppression and increased CETP activity, whereas dietary palmitic acid augments the cholesterol-induced increases in total and LDL-cholesterol by both further suppression of LDL receptor activity and further stimulation of CETP activity. |
| Opposite regulation of hepatic lipase and lecithin: cholesterol acyltransferase by glucocorticoids in rats Jansen, H., A. van Tol, et al. (1992), Biochim Biophys Acta 1128(2-3): 181-5. Abstract: Rats were treated with hydrocortisone, dexamethasone or triamcinolone for 4 days. The effect of treatment on hepatic lipase and lecithin:cholesterol acyltransferase (LCAT) mRNA levels and catalytic activities was determined. Hepatic lipase mRNA was not affected by hydrocortisone, but was decreased after dexamethasone (-28%) and triamcinolone (-54%). Hepatic lipase activity followed the same pattern, it was not affected by hydrocortisone and lowered by dexamethasone (-38%) and triamcinolone (-70%). The LCAT mRNA level in the liver was also not affected by hydrocortisone, but increased upon treatment with dexamethasone (+22%) and triamcinolone (+72%). Plasma LCAT, determined with an excess exogenous substrate (designated LCAT-II), tended to decrease after hydrocortisone treatment (-11%) and was higher after dexamethasone (+21%) and triamcinolone (+22%). The plasma cholesterol esterification rate (designated LCAT-I), determined by incubation of the plasma at 37 degrees C, followed the same pattern. The activity ratio of hepatic lipase/LCAT-II decreased from 1 in the controls to 0.51 after dexamethasone and 0.25 in the triamcinolone-treated animals. The plasma HDL cholesterol concentration in the different groups changed oppositely to the hepatic lipase/LCAT activity ratio. It is concluded that HDL cholesterol is raised by synthetic glucocorticoids due, among other factors, to a lowered hepatic lipase and an increased plasma LCAT activity. The influence of glucocorticoids on these enzymes is, at least partly, explained by the effects on the hepatic mRNA contents. |
| Optimal management of cholesterol levels and the prevention of coronary heart disease in women Mosca, L. J. (2002), Am Fam Physician 65(2): 217-26. Abstract: Coronary heart disease, the leading cause of death in women, is largely preventable. Lifestyle modifications (e.g., diet and exercise) are the cornerstone of primary and secondary prevention. Elevated levels of low-density lipoprotein cholesterol and triglycerides and low levels of high-density lipoprotein cholesterol are significant risk factors for coronary heart disease. Abundant data show inadequate utilization of lipid-lowering therapy in women. Even when women are given lipid-lowering agents, target levels often are not achieved. Recent guidelines from the American Heart Association and the American College of Cardiology encourage a more aggressive approach to lipid lowering in women. The National Cholesterol Education Program Adult Treatment Panel III also supports this strategy and significantly expands the number of women who qualify for intervention. |
| Optimal NS0 cell growth in a hollow fiber bioreactor requires increased serum concentration or a cholesterol supplement on the cell side of the fiber Gramer, M. J. and J. Maas (2003), Biotechnol Prog 19(6): 1762-6. Abstract: An NSO/GS cell line secreting a humanized antibody was routinely propagated in a T-flask using 2% serum. For scale-up of antibody production, this cell line was inoculated into a hollow fiber system using the same serum concentration. The metabolic activity increased for a few days in the hollow fiber system, but invariably the activity dropped dramatically as the cells died by day 7. A hollow fiber micro-bioreactor was used as a screening tool to examine possible reasons for cell death in the large-scale system. As seen in the hollow fiber system, cells died when 2% serum was used either on the cell side only or on both sides of the fiber in the micro-bioreactor. In contrast, the use of 20% serum on the cell side of the fiber and basal medium on the non-cell side resulted in good cell expansion at high viability. Regardless of the cell side serum concentration, no further growth enhancements were seen when up to 20% serum was placed on the non-cell side of the fiber. These results suggest that a serum component that does not readily cross the fiber is limiting cell growth in the hollow fiber bioreactors. The addition of a cholesterol-rich lipid supplement resulted in better cell growth in the micro-bioreactor, while the addition of other non-cholesterol lipid supplements resulted in no growth enhancement. The growth-enhancing properties of the cholesterol supplement were more pronounced at lower serum concentrations, suggesting that poor growth at low serum concentration was due to suboptimal cholesterol levels. When the cell side serum concentration was increased to 20% in the hollow fiber system, cells grew and filled the bioreactor, allowing a 39-day production run. These results demonstrate that this NSO cell line requires an increased cell side serum concentration for optimal growth and that this requirement is likely due to the inherent cholesterol dependency of this cell line. |
| Optimal serum cholesterol and efficacy of methods for lowering cholesterolemia Emmerich, J., D. Thomas, et al. (1992), Arch Mal Coeur Vaiss 85 Spec No 3: 59-65. Abstract: Analysis of epidemiological studies enables definition of the optimal serum cholesterol level between 2 and 2.2 g/l (5.2 and 5.7 mmol/l). Higher levels are associated with an exponential risk of coronary artery disease: lower levels should be interpreted with caution because of the J-shaped curve of global mortality reported in several trials. In primary prevention, therapeutic trials have clearly shown that a significant reduction in the number of coronary event may be obtained by lowering the serum cholesterol (15 for every 1,000 patients treated). In trials performed to date this benefit has not resulted in any gain in global mortality. In secondary prevention, the benefits of lowering serum cholesterol on the incidence of coronary disease seems identical in terms of relative risk to that observed in primary prevention. Nevertheless, the benefits in terms of absolute risk are much higher because of the high incidence of coronary mortality in a patient population with a previous coronary event. Thus, for 1,000 patients treated, there are 50 less cardiac events and this is reflected in a reduction of global mortality of about 20 for every 1,000 patients treated. |
| Optimization and characterization of a sphingomyelin/cholesterol liposome formulation of vinorelbine with promising antitumor activity Semple, S. C., R. Leone, et al. (2005), J Pharm Sci 94(5): 1024-38. Abstract: Vinorelbine (VRL) is a particularly lipophilic member of the vinca alkaloids which, as a class of drugs, exhibit improved cytotoxicity and therapeutic activity through increased duration of exposure. Here, we describe and optimize a sphingomyelin/cholesterol (SM/Chol) liposome formulation of VRL to maximize in vivo drug retention, plasma circulation time, and therapeutic activity. VRL was efficiently encapsulated (>90%) into 100 nm liposomes using an ionophore-mediated loading method. VRL retention in SM/Chol liposomes after intravenous injection in mice was dependent on drug-to-lipid ratio (D/L), with higher D/L ratios exhibiting increased drug retention (0.3 > 0.2 > 0.1, wt/wt) and improved pharmacokinetics. Cryo-electron microscopic examination of a high D/L ratio formulation indicated that the intravesicular regions of these liposomes were electron dense compared with empty liposomes. The optimized, high D/L ratio SM/Chol VRL formulation showed promising activity against subcutaneous B16 melanoma tumors compared with VRL or SM/Chol formulations of vincristine or vinblastine. Finally, the stability of the formulation was excellent (<5% drug leakage, >99% intact VRL, no changes in liposome size after 1 year at 2-8 degrees C). The optimized drug retention properties of the SM/Chol formulation of VRL, combined with its promising antitumor activity and pharmaceutical stability, make this formulation an excellent candidate for future clinical development. |
| Optimization of cholesterol reduction principles and clinical results of dual inhibition von Hodenberg, E. (2005), Internist (Berl) 46 Suppl 1: S18-23. Abstract: Ezetimibe is a recently developed compound, which inhibits intestinal cholesterol absorption. Because there are hints for an increase of cholesterol absorption during statin therapy, the combination of Ezetimibe with a statin seems to be appropriate. This dual approach -- inhibition of intestinal cholesterol absorption and hepatic cholesterol synthesis -- offers a very potent reduction of cholesterol. The combination of statins with Ezetimibe leads to a further reduction of LDL-cholesterol up to 12-21%. The dual inhibition causes a more effective reduction of LDL-cholesterol than a statin monotherapy. LDL treatment goals can be reached more easily, and possible side effects of otherwise necessary high doses of statins can be avoided. Clinical endpoint studies with Ezetimibe are underway. |
| Optimization of cholesterol removal by probiotics in the presence of prebiotics by using a response surface method Liong, M. T. and N. P. Shah (2005), Appl Environ Microbiol 71(4): 1745-53. Abstract: Lactobacillus casei ASCC 292 was grown in the presence of six prebiotics, namely, sorbitol, mannitol, maltodextrin, high-amylose maize, fructooligosaccharide (FOS), and inulin, in order to determine the combination of probiotic and prebiotics that would remove the highest level of cholesterol. A first-order model showed that the combination of L. casei ASCC 292, FOS, and maltodextrin was the most efficient for the removal of cholesterol, and the optimum experimental region was developed by using the steepest ascent. This led to the middle points of probiotic (1.70% wt/vol), FOS (4.80% wt/vol), and maltodextrin (6.80% wt/vol) for the development of a central composite design for optimization. Perturbation plot, response surface, and coefficient estimates showed that all three factors had significant quadratic effects on cholesterol removal, with FOS showing the most conspicuous quadratic change. A second-order polynomial regression model estimated that the optimum condition of the factors for cholesterol removal by L. casei ASCC 292 is 1.71% (wt/vol) probiotic, 4.95% (wt/vol) FOS, and 6.62% (wt/vol) maltodextrin. Validation experiments showed that the predicted optimum conditions were more efficient than the high and low levels of the factors and the center points. A response surface method proved reliable for developing the model, optimizing factors, and analyzing interaction effects. Analyses of growth, substrate utilization, growth yield, mean doubling time, and short-chain fatty acid (SCFA) production by the use of quadratic models indicated that cholesterol removal was growth associated. The concentration of L. casei ASCC 292 had the most significant quadratic effect on all responses studied, except for substrate utilization and SCFA production, which were significantly (P < 0.05) influenced by the interactions between the probiotic and both prebiotics, indicating that they were closely associated with the uptake of prebiotics. |
| Optimization of cholesterol removal, growth and fermentation patterns of Lactobacillus acidophilus ATCC 4962 in the presence of mannitol, fructo-oligosaccharide and inulin: a response surface methodology approach Liong, M. T. and N. P. Shah (2005), J Appl Microbiol 98(5): 1115-26. Abstract: AIMS: To optimize cholesterol removal by Lactobacillus acidophilus ATCC 4962 in the presence of prebiotics, and study the growth and fermentation patterns of the prebiotics. METHODS AND RESULTS: Lactobacillus acidophilus ATCC 4962 was screened in the presence of six prebiotics, namely sorbitol, mannitol, maltodextrin, hi-amylose maize, fructo-oligosaccharide (FOS) and inulin in order to determine the best combination for highest level of cholesterol removal. The first-order model showed that the combination of inoculum size, mannitol, FOS and inulin was best for removal of cholesterol. The second-order polynomial regression model estimated the optimum condition of the factors for cholesterol removal by L. acidophilus ATCC 4962 to be 2.64% w/v inoculum size, 4.13% w/v mannitol, 3.29% w/v FOS and 5.81% w/v inulin. Analyses of growth, mean doubling time and short-chain fatty acid (SCFA) production using quadratic models indicated that cholesterol removal and the production of SCFA were growth associated. CONCLUSIONS: Optimum cholesterol removal was obtained from the fermentation of L. acidophilus ATCC 4962 in the presence of mannitol, FOS and inulin. Cholesterol removal and the production of SCFA appeared to be growth associated and highly influenced by the prebiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: Response surface methodology proved reliable in developing the model, optimizing factors and analysing interaction effects. The results provide better understanding on the interactions between probiotic and prebiotics for the removal of cholesterol. |
| Optimization studies of components in enzymatic cholesterol reagents containing cholesterol oxidase from Nocardia erythropolis, Streptomyces sp, or Pseudomonas fluorescens Lolekha, P. H. and Y. Teerajetkul (1996), J Clin Lab Anal 10(4): 167-76. Abstract: Although enzymatic methods for serum cholesterol determination are widely used in clinical laboratories, little is known about the optimization of each component in enzymatic reagents. We investigated the optimal components in the reagents containing cholesterol oxidase isolated from Nocardia erythropolis, Streptomyces sp, or Pseudomonas fluorescens. The optimal components in the reagents are: cholesterol oxidase 250 (Nocardia erythropolis), 250 (Streptomyces sp), or 300 (Pseudomonas fluorescens) U/L, cholesterol esterase 200 U/L, peroxidase 10,000 U/L, sodium cholate 3 mmol/L, 4-aminoantipyrine 0.5 mmol/L, phenol 20 mmol/L, Triton X-100 2 mL/L, and phosphate buffer, pH 7.0. Lower reaction sensitivity and lower cholesterol linearity, < 18.1 mmol/L (700 mg/dL), could be obtained by using lower components than those suggested above. Pseudomonas fluorescens were an improper source for cholesterol oxidase; either Nocardia erythropolis or Streptomyces was suitable cholesterol oxidase. We prefer using Streptomyces sp cholesterol oxidase because of its economical cost and longest reagent stability. Sodium cholate must be included in the enzymatic reagent to prevent turbidity. However, sodium cholate of > 5 mmol/ L will suppress the reaction resulting in low cholesterol linearity. |
| Optimizing cholesterol lowering therapy: contribution of the Post Coronary Artery Bypass Graft Trial Campeau, L., G. Knatterud, et al. (1997), Eur Heart J 18(11): 1683-5. |