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D N Rudra

Publications and source records attributed to D N Rudra.

8 recordsLinked to original sources
PubMed1989

The concentration of apolipoprotein A-II in human peripheral lymph.

The concentration of apolipoprotein A-I (apoA-I) and of apolipoprotein A-II (apoA-II) was determined immunoelectrophoretically in lymph and plasma of six subjects. The concentration in lymph of apoA-I was 20.3 +/- 3.1 mg/dl, that of apoA-II was 4.6 +/- 0.5 mg/dl. The ratio of the concentration in lymph over that in plasma (CL/CP) for apoA-I was 0.14 +/- 0.1, that for apoA-II 0.14 +/- 0.01. Lymph and plasma samples from two subjects were fractionated by exclusion chromatography and the concentration of both apolipoproteins in resulting fractions was determined immunoelectrophoretically. ApoA-I of lymph eluted with fractions spanning a wider range of particle sizes than plasma apoA-I, while lymph apoA-II eluted predominantly with fractions that contained particles corresponding in size to plasma apoA-II-containing particles. It appears that the largest and smallest lymph HDL represent subspecies of Lp(A-I without A-II). These findings are discussed in the context of their possible bearing on initial stages of reverse transport of cholesterol.

Apolipoprotein A-I↗
PubMed1985

Human lymphedema fluid lipoproteins: particle size, cholesterol and apolipoprotein distributions, and electron microscopic structure.

The concentration of cholesterol, apolipoproteins A-I, B, and E has been determined in lymphedema fluid from nine patients with chronic primary lymphedema. The concentrations were: 38.14 +/- 21.06 mg/dl for cholesterol, 15.6 +/- 6.17 mg/dl for apolipoprotein A-I, 7.5 +/- 2.8 mg/dl for apolipoprotein B, and 1.87 +/- 0.50 mg/dl for apolipoprotein E. These values represent 23%, 12%, 6%, and 38% of plasma concentrations, respectively. The ratio of esterified to unesterified cholesterol in lymphedema fluid was 1.46 +/- 0.45. Lipoproteins of lymphedema fluid were fractionated according to particle size by gradient gel electrophoresis and by exclusion chromatography. Gradient gel electrophoresis showed that a majority of high density lipoproteins (HDL) of lymphedema fluid were larger than ferritin (mol wt 440,000) and smaller than low density lipoproteins (LDL); several discrete subpopulations could be seen with the large HDL region. Fractionation by exclusion chromatography showed that more than 25% of apolipoprotein A-I and all of apolipoprotein E in lymphedema fluid was associated with particles larger than plasma HDL2. Apolipoprotein A-I also eluted in fractions that contained particles the size of or smaller than albumin. Isolation of lipoproteins by sequential ultracentrifugation showed that less than 25% of lymphedema fluid cholesterol was associated with apolipoprotein B. The majority of apolipoprotein A-containing lipoproteins of lymphedema fluid were less dense than those in plasma. Ultracentrifugally separated fractions of lipoproteins were examined by electron microscopy. The fraction d less than 1.019 g/ml contained little material, while fraction d 1.019-1.063 g/ml contained two types of particles: round particles 17-26 nm in diameter and square-packing particles 13-17 nm on a side. Fractions d 1.063-1.085 g/ml had extensive arrays of square-packing particles 13-14 nm in size. Fractions d 1.085-1.11 g/ml and fractions d 1.11-1.21 g/ml contained round HDL, 12-13 nm diameter and 10 nm diameter, respectively. Discoidal particles were observed infrequently.

Apolipoproteins↗
PubMed1984

The distribution of cholesterol and apoprotein A-I between the lipoproteins in plasma and peripheral lymph from normal human subjects.

The lipoproteins of peripheral lymph and plasma from normal human subjects were separated according to their density by sequential ultracentrifugation and according to their size by gradient gel electrophoresis and gel exclusion chromatography. High density lipoproteins (HDL) carried a higher proportion of the total cholesterol in lymph than in plasma. Within the HDL fraction, the less dense and more lipid-rich component (HDL2) carried a higher proportion of the total HDL cholesterol in lymph than in plasma. Gradient gel electrophoresis showed (1) a higher proportion of large to small HDL particles in lymph than in plasma and (2) the presence of at least three populations of apo A-I-containing lipoproteins with Stokes diameters larger than the Stokes diameter of HDL2. Separation by gel exclusion chromatography showed that the proportion of large HDL particles with a high cholester: apo A-I ratio was greater in lymph than in plasma. In view of the sieving effect of the blood capillaries, which favours the passage across the capillary walls of smaller vs larger particles, we suggest that the higher ratio of large to small HDL particles in lymph than in plasma is due to the conversion of small to large HDL in the interstitial fluid by incorporation of cholesterol and other lipids from extravascular cells into the smaller particles.

Apolipoprotein A-I↗
PubMed1982

Further evidence for the role of high density lipoprotein in the removal of tissue cholesterol in vivo.

The lipoproteins of human peripheral lymph and plasma were separated according to particle size by polyacrylamide gradient gel electrophoresis. All samples of lymph contained lipoproteins that moved to the same positions on the gel as plasma LDL and plasma HDL. Some samples of lymph also contained lipoproteins with the mobility of VLDL and IDL. The lymph lipoproteins corresponding to plasma LDL reacted with anti-LDL serum and those corresponding to plasma HDL reacted with anti-HDL serum. In the lipoprotein fraction with the mobility of HDL, the proportion of particles larger than catalase was greater in lymph than in plasma. It is suggested that the shift in size distribution towards larger HDL particles in lymph compared with plasma is due to uptake of cholesterol from extravascular tissue by HDL particles after they have reached the interstitial fluid from the plasma, rather than to preferential movement of larger particles across the capillary walls.

Cholesterol↗
PubMed1980

Evidence for the presence of tissue-free cholesterol in low density and high density lipoproteins of human peripheral lymph.

The specific radioactivity of free and esterified cholesterol in the lipoproteins of human peripheral lymph was measured in 4 normal human subjects at various intervals after labelling the tissue cholesterol by a single intravenous injection of [14C]cholesterol. The free : esterified cholesterol specific-activity ratios in lymph LDL and HDL at short and long intervals after labelling in vivo suggest that both lipoproteins were capable of acting as acceptors for tissue-free cholesterol, but that in 3 of the 4 subjects the predominant acceptor was HDL.

Carbon Radioisotopes↗
PubMed1977

The passage of apoproteins from plasma lipoproteins into the lipoproteins of peripheral lymph in man.

1. The transport of apoprotein B from the lipoprotein of plasma into the lipoproteins of lymph draining the foot has been studied in four men with type III hyperlipoproteinaemia. 2. Three subjects were given autologous 125I-labelled very-low-density lipoprotein (VLDL) and 131I-labelled low-density lipoprotein (LDL) by intravenous injection; the fourth was given autologous 125I-labelled VLDL and 131I-labelled intermediate-density lipoprotein (IDL) plus LDL. 3. The 125I/131I ratios in serum and lymph apoprotein B, and the 125I and 131I specific radioactivities of apoprotein B in VLDL, IDL and LDL from serum and lymph, indicate that apoprotein B in the circulating VLDL can reach peripherallymph without the intermediacy of circulating LDL.

Adult↗