Sources of error in determinations of carnitine and acylcarnitine in plasma.

1984 ◽  
Vol 30 (2) ◽  
pp. 316-318 ◽  
Author(s):  
R C Fishlock ◽  
L L Bieber ◽  
A M Snoswell
Keyword(s):  
Perchloric Acid ◽  
Volume Of Fluid ◽  
Fluid Volume ◽  
Free Carnitine ◽  
Short Chain ◽  
Distilled Water ◽  
Plasma Samples ◽  
Long Chain ◽  
Total Fluid

Abstract Radioactive and nonradioactive L-carnitine and acyl-L-carnitine were used to evaluate the washing procedures used during the determination of free, total, short-chain, and long-chain acylcarnitine in human and sheep plasma. The volume of fluid trapped by the protein precipitated by perchloric acid is approximately 24% of the total fluid volume and thus contains 24% of free carnitine and short-chain acylcarnitine. Washing twice with distilled water removes about 25% of the long-chain acylcarnitine along with the trapped free carnitine and short-chain acylcarnitines. Washing the pellet twice with a 60 g/L solution of perchloric acid completely removes the trapped free carnitine and short-chain acylcarnitine but does not remove the bound long-chain acylcarnitines. Thus washing with perchloric acid is essential for accurate measurement of long-chain acylcarnitines in plasma samples.

scholarly journals A fixation procedure suitable for autoradiography of endogenous long-chain acyl carnitine.

1985 ◽  
Vol 33 (8) ◽  
pp. 744-748 ◽  
Author(s):  
M T Knabb ◽  
G G Ahumada ◽  
B E Sobel ◽  
J E Saffitz
Keyword(s):  
Subcellular Localization ◽  
Selective Extraction ◽  
Total Radioactivity ◽  
Water Soluble ◽  
Free Carnitine ◽  
Neonatal Rat ◽  
Short Chain ◽  
Tissue Processing ◽  
Chain Acyl ◽  
Long Chain

A tissue processing procedure was evaluated for fixation of endogenous long-chain acyl carnitine (LCA) to facilitate autoradiographic subcellular localization of this amphiphile. Suspensions of neonatal rat myocytes labeled with exogenous 14C-palmitoyl carnitine retained 85.2% of the radiolabel after tissue processing. Autoradiography demonstrated no significant translocation of radiolabeled LCA from myocytes to unlabeled sheep erythrocytes mixed in equal proportions and processed together. To evaluate endogenous LCA fixation, cultured myocytes were incubated for 3 days with 3H-carnitine. Radioactivity was distributed in LCA, short-chain acyl carnitine, and free carnitine pools in proportion to the physiological concentrations of the metabolites traced. Before tissue processing, LCA contained 4.5% of total radioactivity. After tissue processing, labeled water-soluble components were lost and 88% of the retained radioactivity was in the LCA pool. The enrichment of endogenous LCA radioactivity was attributable to the selective extraction of endogenous short-chain and free carnitine. Nearly 75% of endogenous LCA was preserved. In contrast, 99.5% of both endogenous short-chain and free carnitine were extracted. Thus, endogenous LCA can be selectively preserved, permitting quantitative subcellular localization of this amphiphile with ultrastructural autoradiography.

Effect of HCl Concentration and Acetone Washing on the Dielectric and Conduction Properties of Polyaniline Salts

2021 ◽  
Vol 14 ◽  
Author(s):  
Jayashree Mohanty ◽  
S.R. Mishra ◽  
Tanmaya Badapanda ◽  
S. Anwar
Keyword(s):  
Electrical Conductivity ◽  
Electrical Properties ◽  
Acid Concentration ◽  
Charge Carriers ◽  
Short Chain ◽  
Water Medium ◽  
Distilled Water ◽  
Chain Polymer ◽  
Pani Salt ◽  
Long Chain

Aims: The aim of the work is to study the effect of acid concentration and acetone washing on electrical properties of Polyaniline (PANI) salts prepared through chemically oxidative polymerization. Background: The frequency dependent conductivity and dielectric permittivity provide important information on the electrical properties of conducting polymers which gives information regarding their utility in electronic applications. Objective: Hence, the present study is based on the comparative the electrical properties study (dielectric and electrical conductivity) of PANI salts prepared in two different media like water and 1M HCl along with study regarding effect acetone washing on the said electrical properties of the polymer samples. Methods: PANI salts are synthesized through chemical oxidative polymerisation of aniline hydrochloride with the oxidant ammonium persulphate in two different media like water and 1M HCl. One part of the PANI salt samples were washed with distilled water after synthesis and another part of the polymer samples were washed with distilled water followed by acetone to study the effect of acetone washing on the electrical properties of polymer samples. Results: Non-acetone washed PANI salt prepared in water medium shows the highest dielectric as well as electrical conductivity due to the increased charge carriers provided both by long chain polymer as well as short chain oligomers. When the acid concentration is increased to 1M there may be loss of protons accompanied by pairing of free radicals to form quinoimine units that leads to the loss of charge carriers consequently decreasing the dielectric constant and electrical conductivity. Conclusion : PANI salt prepared in water shows the highest dielectric as well as conductivity due to the increased charge carriers provided both by long chain polymer as well as short chain oligomers.

Improved radiochemical assay for carnitine and its derivatives in plasma and tissue extracts.

1978 ◽  
Vol 24 (1) ◽  
pp. 32-35 ◽  
Author(s):  
J A Pace ◽  
R W Wannemacher ◽  
H A Neufeld
Keyword(s):  
Perchloric Acid ◽  
Metabolic Disorders ◽  
Clinical Applications ◽  
Short Chain ◽  
Acetyl Coa ◽  
Tissue Extracts ◽  
Analytical Recovery ◽  
Long Chain

Abstract We describe the measurement of carnitine and short-chain and long-chain acylcarnitines in perchloric acid extracts of liver and muscle. [1-14C]Acetyl-CoA is used, and labeled acetylcarnitine is measured with a sensitivity of less than 1 to 50 nmol of L-carnitine per 50-microliter sample. Samples frozen at -20 degrees C lost no carnitine during several months. Analytical recovery of carnitine (5 nmol) added to 50-microliter perchloric acid extracts of liver was 103 +/- 2%. This method may be suitable for clinical applications such as screening patients with muscle and metabolic disorders.

Presence of nonesterified and acylcarnitine in human polymorphonuclear leukocytes and mononuclear cells.

1987 ◽  
Vol 33 (4) ◽  
pp. 533-535 ◽  
Author(s):  
K Katrib ◽  
H A Adlouni ◽  
G Férard
Keyword(s):  
Perchloric Acid ◽  
Whole Blood ◽  
Blood Cells ◽  
Polymorphonuclear Leukocytes ◽  
Mononuclear Cells ◽  
Short Chain ◽  
The Mean ◽  
Total Carnitine ◽  
Human Polymorphonuclear Leukocytes ◽  
Long Chain

Abstract We demonstrate the presence of nonesterified carnitine and acylcarnitine in leukocytes, but not in erythrocytes, from 16 healthy adults. After carefully separating the different kinds of blood cells we measured significant amounts of nonesterified carnitine and acylcarnitine in polymorphonuclear leukocytes (28.5 +/- 6.1 and 18.5 +/- 6.3 mumol/10(9) cells) and mononuclear cells (25.4 +/- 5.2 and 14.8 +/- 4.5 mumol/10(9) cells). We also measured nonesterified carnitine, long-chain acylcarnitine, and short-chain acylcarnitine in plasma after fractionation with perchloric acid and obtained the following values (mean +/- SD): 41.4 +/- 2.6, 3.9 +/- 1.2, and 6.0 +/- 1.6 mumol/L, respectively. The mean percentages of total carnitine (n = 6) in polymorphonuclear leukocytes, mononuclear cells, and plasma were approximately 62%, 27%, and 13% of whole-blood carnitine, respectively (mean recovery was 102%). The percentage of acylated carnitine was 37% in leukocytes, as compared with 19% in plasma.

Human Forearm Arteriovenous Differences of Carnitine, Short-Chain Acylcarnitine and Long-Chain Acylcarnitine

1989 ◽  
Vol 77 (4) ◽  
pp. 413-416 ◽  
Author(s):  
Dr K. Bartlett ◽  
A. K. M. J. Bhuiyan ◽  
A. Aynsley-Green ◽  
P. C. Butler ◽  
K. G. M. M. Alberti
Keyword(s):  
Fatty Acids ◽  
Free Carnitine ◽  
Short Chain ◽  
Fasted State ◽  
Esterified Fatty Acids ◽  
Molar Basis ◽  
Human Forearm ◽  
Net Uptake ◽  
Net Release ◽  
Long Chain

1. Forearm arterial and venous concentrations of free carnitine, short-chain acylcarnitine, long-chain acylcarnitine, glucose, lactate, pyruvate, alanine, non-esterified fatty acids, glycerol, 3-hydroxybutyrate and acetoacetate were measured in fasted adult subjects. 2. In all subjects there was net uptake of short-chain acylcarnitine, 3-hydroxybutyrate and acetoacetate and net release of free carnitine and non-esterified fatty acids. The arteriovenous differences of the other metabolites were not consistent. 3. These observations support the concept that short-chain acylcarnitine (largely acetylcarnitine) contributes to the flux of metabolic fuels from the liver to muscle in the fasted state, although to a limited extent in comparison with 3-hydroxybutyrate (< 5% on a molar basis).

scholarly journals Determination of free, short-chain acyl and long-chain acyl carnitines in milk and milk products.

1988 ◽  
Vol 41 (5) ◽  
pp. 397-404 ◽  
Author(s):  
Michio HAMAMOTO ◽  
Kousou SHIMODA ◽  
Norio MATSUURA ◽  
Hiroaki MATSUURA
Keyword(s):  
Short Chain ◽  
Milk Products ◽  
Chain Acyl ◽  
Long Chain

The Effects of Direction and Velocity of Movement, and Intra-Articular Fluid Volume on Intra-Articular Pressue

1988 ◽  
Vol 01 (03/04) ◽  
pp. 113-121 ◽  
Author(s):  
S. F. Straface ◽  
P. J. Newbold ◽  
S. Nade
Keyword(s):  
Dynamic Pressure ◽  
Volume Of Fluid ◽  
Joint Capsule ◽  
Fluid Volume ◽  
Structural Configuration

levels. In joints with simulated acute effusion the effect of position on IAP was dependent upon the volume of fluid in the joint. The results indicate that dynamic pressure levels in the moving knee are related to the movements of the joint. The characteristic and reproducible patterns of pressure may reflect changes in the structural configuration of the joint capsule and surrounding tissues during movement, and are influenced by the amount of fluid in the joint.

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