[Clinical significance of small, dense LDL cholesterol in patients with hyperlipidemia and type 2 diabetes].

We investigated the serum levels of small, dense LDL-cholesterol (sd LDL-C) in patients with hyperlipidemia and type 2 diabetes. An analytical assay was used to determine the levels of sd LDL-C, employing a filter method using a separating agent of polyanion and divalent cation natures. Reference intervals of sd LDL-C in normal healthy subjects (n=113) ranged from 8.

[A simple separative method for measuring serum amyloid A in high-density-lipoprotein and low-density-lipoprotein fractions using the phosphotungstic acid-Mg2+ precipitation procedure].

We developed a simple separative method for measuring serum amyloid A (SAA) in both high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) fractions. It was devised using the SAA agglutination method and phosphotungstic acid-Mg2+ precipitation procedure for evaluating HDL-cholesterol (HDL-C). The new method is also able to detect amyloid A (AA) in each fraction with precision.

[Clinical significance of serum-glycated apolipoprotein B measured by the digestion LDL sediment fraction with protease].

We previously reported an assay method for serum glycated aplipoprotein B (G-apo B) using protease. The present study demonstrated correlations between serum G-apo B levels and some other serum parameters, from which a clinical significance of the G-apo B in diabetics was deduced. Serum G-apo B determined by the present method was significantly correlated with glyco-albumin and glycohemoglobin.

[Convenient assay for glycated apolipoprotein B using protease].

The aim of this study is to develop a convenient method for monitoring glycated apolipoprotein B levels. Serum sample was treated with dextran-magnesium and the resulting precipitates were subjected to glycated albumin assay. Dissolving the precipitates by Triton X-100 and digesting by proteinase K enable the establishment of stable and sensitive assay.

A simple precipitation method for measuring sialic acid in apolipoprotein B-containing lipoproteins in plasma.

Background: A convenient method for the measurement of sialic acid in plasma apoB-containing lipoproteins is described.

Methods: Dextran sulphate-Mg(2+) precipitation and enzymatic sialic acid assay were combined and applied to analysis of plasma from 96 healthy controls and 136 hyperlipidaemic subjects of types IIa (n=46), IIb (n=43), and IV (n=47).

Results: The sialic acid concentrations (mean+/-SD) in plasma apoB-containing lipoproteins were 19.

The absence of evidence for major effects of the frequent SNP +299G>A in the resistin gene on susceptibility to insulin resistance syndrome associated with Japanese type 2 diabetes.

Resistin, specifically secreted from adipocytes, antagonizes insulin and represents a promising candidate gene for type 2 diabetes. We reported that a frequent single nucleotide polymorphism (SNP) +299G>A in this gene is not associated with type 2 diabetes. To determine whether this SNP affects insulin resistance syndrome associated with type 2 diabetes, we examined its effects on susceptibility to obesity, hyperlipidemia and hypertension in type 2 diabetic subjects and on susceptibility to type 2 diabetes by interaction with other frequent genes involved in lipid metabolism, namely, beta3-adrenergic receptor (b3AR) Trp64Arg, phosphodiesterase 3B (PDE3B) c.

[Clinical significance of serum LpA-I levels measured by immunoturbidimetric assay in type 2 diabetes mellitus patients].

Previously, we developed an immunoturbidimetric assay method for lipoprotein A-I(LpA-I) on sera pre-absorbed with anti-apolipoprotein A-II. In the present study, correlations between serum lipoprotein A-I and other serum parameters levels were examined and LpA-I levels were studied in patients with type 2 diabetes mellitus. The serum levels of LpA-I did not correlate with those of diabetic markers such as fasted blood glucose, glycohemoglobin(HbA1c) and fructosamine, but correlated well with the levels of total cholesterol and HDL cholesterol, phospholipids, apolipoprotein A-I and seemed to correlate inversely with arteriosclerosis index.

Glycated apolipoprotein A-I assay by combination of affinity chromatography and latex immunoagglutination.

The degree of glycation of plasma apolipoprotein A-I was measured by a combination of gel filtration, boronate affinity chromatography and latex immunoagglutination. The plasma concentrations of apolipoprotein A-I determined by this combination method (y) correlated well with those determined by turbidimetric immunoassay (x) (y=1.12x + 1.

[Development of a serum lipoprotein A-I immunoassay method].

We developed an immunoturbidimetric assay method for lipoprotein A-I by treating sera with an anti-apo lipoprotein A-II and A-I antibody sequentially. The assay is sensitive to detect lipoprotein A-I as little as 155 mg/l with good precision. There was a good correlation in the level of serum lipoprotein A-I between the present assay and a conventional differential electroimmunoassay on ready-to-use plates (r = 0.

[Lipid peroxide and antioxidants in the elderly].

Aging is associated with changes in physical characteristics and decline of many physiological functions. The aging process have been described by various theories, in particular the free radical theory of aging has received widespread attention. It has been accepted that the oxidative stress or damage induced by free radicals is related to aging.

Decreased susceptibility of glycated very low density lipoproteins to lipoprotein lipase in vitro and prevention by glutathione.

In vitro glycation of very low density lipoprotein (VLDL) reduced the susceptibility to lipoprotein lipase (LPL) as the level of glycation increased. Addition of reduced glutathione to an incubation medium of serum and glucose interfered with glycation of serum proteins when the concentration of reduced glutathione was higher than 10 mM. At concentrations higher than 25 mM, it also significantly prevented the glycation induced reduction of fatty acid releases from VLDL by LPL.

Aging changes of riboflavin concentration and glutathione reductase activity in erythrocytes.

Aged erythrocytes obtained by fractionation using gradient centrifugation with Dextran 40, showed lower glutathione reductase activity and riboflavin content than young cells. However, both young and old cells displayed almost the same increase in enzyme activity upon addition of flavin adenine dinucleotide to the test hemolysate in vitro. The lipid peroxide content in the cell membranes showed no consistent changes with aging.