Ether Eluate Research Articles

A modified approach in testing the ether eluate to overcome the hurdle in reading the results.

A modified approach in testing the ether eluate to overcome the hurdle in reading the results.

Elemental and spectroscopic characterization of fractions of an acidic extract of oil sands process water

‘Naphthenic acids’ (NAs) in petroleum produced water and oil sands process water (OSPW), have been implicated in toxicological effects. However, many are not well characterized. A method for fractionation of NAs of an OSPW was used herein and a multi-method characterization of the fractions conducted.The unfractionated OSPW acidic extract was characterized by elemental analysis, electrospray ionization-Orbitrap-mass spectrometry (ESI-MS), and an esterified extract by Fourier Transform infrared (FTIR) and ultraviolet–visible (UV) absorption spectroscopy and by comprehensive multidimensional gas chromatography–MS (GCxGC–MS). Methyl esters were fractionated by argentation solid phase extraction (Ag+ SPE) and fractions eluting with: hexane; diethyl ether: hexane and diethyl ether, examined. Each was weighed, examined by elemental analysis, FTIR, UV, GC–MS and GCxGC–MS (both nominal and high resolution MS). The ether fraction, containing sulfur, was also examined by GCxGC–sulfur chemiluminescence detection (GCxGC–SCD).The major ions detected by ESI-MS in the OSPW extract were assigned to alicyclic and aromatic ‘O2’ acids; sulfur was also present. Components recovered by Ag+ SPE were also methyl esters of alicyclic and aromatic acids; these contained little sulfur or nitrogen. FTIR spectra showed that hydroxy acids and sulfoxides were absent or minor. UV spectra, along with the C/H ratio, further confirmed the aromaticity of the hexane:ether eluate.The more minor ether eluate contained further aromatics and 1.5% sulfur. FTIR spectra indicated free carboxylic acids, in addition to esters. Four major sulfur compounds were detected by GCxGC–SCD. GCxGC–high resolution MS indicated these were methyl esters of C18 S-containing, diaromatics with ⩾C3 carboxylic acid side chains.

Retinoid Absorption and Storage Is Impaired in Mice Lacking Lecithin:Retinol Acyltransferase (LRAT)

Lecithin:retinol acyltransferase (LRAT) is believed to be the predominant if not the sole enzyme in the body responsible for the physiologic esterification of retinol. We have studied Lrat-deficient (Lrat-/-) mice to gain a better understanding of how these mice take up and store dietary retinoids and to determine whether other enzymes may be responsible for retinol esterification in the body. Although the Lrat-/- mice possess only trace amounts of retinyl esters in liver, lung, and kidney, they possess elevated (by 2-3-fold) concentrations of retinyl esters in adipose tissue compared with wild type mice. These adipose retinyl ester depots are mobilized in times of dietary retinoid insufficiency. We further observed an up-regulation (3-4-fold) in the level of cytosolic retinol-binding protein type III (CRBPIII) in adipose tissue of Lrat-/- mice. Examination by electron microscopy reveals a striking total absence of large lipid-containing droplets that normally store hepatic retinoid within the hepatic stellate cells of Lrat-/- mice. Despite the absence of significant retinyl ester stores and stellate cell lipid droplets, the livers of Lrat-/- mice upon histologic analysis appear normal and show no histological signs of liver fibrosis. Lrat-/- mice absorb dietary retinol primarily as free retinol in chylomicrons; however, retinyl esters are also present within the chylomicron fraction obtained from Lrat-/- mice. The fatty acyl composition of these (chylomicron) retinyl esters suggests that they are synthesized via an acyl-CoA-dependent process suggesting the existence of a physiologically significant acyl-CoA:retinol acyltransferase.

Quantitation of red cell–bound IgG, IgA, and IgM in patients with autoimmune hemolytic anemia and blood donors by enzyme-linked immunosorbent assay

Abstract This paper describes an enzyme immunoassay for the quantitative determination of IgG, IgA, and IgM immunoglobulins on RBCs. Ether eluates made from RBCs were followed by an enzyme-linked immunosorbent assay of immunoglobulin concentration. Calibration curves were derived from immunoglobulin standards and the number of molecules of each isotype per RBC was calculated. The assay was carried out in 200 healthy blood donors and 62 patients with warm autoimmune hemolytic anemia (AIHA), two of them with a negative DAT. For healthy blood donors, mean values were 58 IgG, 16 IgA, and 3 IgM molecules per RBC. For patients with a positive DAT, the mean values were 3435 IgG, 157 IgA, and 69 IgM molecules per RBC. An increased level of IgA was found in 12 patients without IgA autoantibodies demonstrable in RBC eluates. Increased IgG levels were also observed in patients with a negative DAT and, in one case, an increased level of IgA was also found. The enzyme-linked immunosorbent assay using ether eluates is a sensitive method for quantitating RBC autoantibodies in patients with AIHA as well as immunoglobulins bound to RBCs in healthy individuals. Immunohematology 2003;19:47–53.

A comparison of the effects of various purification treatments on the oxidative stability of squid visceral oil

AbstractFactors influencing the oxidative stability of refined squid visceral oil after various purification treatments were evaluated. Squid visceral oil was treated by refining, steam deodorizing, molecular distillation, Sep‐Pak cartridge extraction, alumina adsorption, EDTA solution washing, and column chromatography, and the treated oils were compared for oxidative stability. Sep‐Pak cartridge extraction and alumina adsorption were designed to eliminate phenolic compounds, α‐tocopherol, phospholipids, and metal ions from the oil. The oxidative stability was measured using PV and increase in weight. The refined oil and the deodorized oil were the most stable, and the highly purified oil was the least stable. However, alumina‐adsorbed oil that had been washed with EDTA was more resistant to oxidation than highly purified oil. When refined oil was passed through an activated carbon‐Celite chromatography column, it could be separated into hexane, ether, and ethanol fractions. The ethanol eluate contained more α‐tocopherol and phospholipids than the ether eluate. The addition of the ethanol eluate extracted from squid visceral oil to the highly purified oil resulted in excellent stability.

The Influence of Aphid-Induced Plant Volatiles on Ladybird Beetle Searching Behavior

Field-collected individuals of the seven-spotted ladybird, Coccinella septempunctata L. (Coleoptera, Coccinellidae), were tested for response to volatiles from aphids (Rhopalosiphum padi (L.)), from aphid-infested barley plants (Hordeum vulgare), and from previously aphid-infested and uninfested plants. The volatiles were collected by conventional polymer entrainment techniques, and diethyl ether eluates of the entrainments were used as odor sources in olfactometer bioassays. C. septempunctata responded positively to volatiles from aphid-infested plants and from previously aphid-infested plants but not to volatiles from uninfested plants or from undisturbed aphids. The ecological implications of the findings are discussed.

Characterization of Elevated Neutrophil-Associated IgG in Various Autoimmune Disorders: Not Anti-Neutrophil Autoantibodies, But Possibly Immune Complexes, Bind to Neutrophils

Neutropenia is frequently observed in a variety of autoimmune disorders. As the mechanism of neutropenia in these disorders, the destruction of neutrophils by anti-neutrophil autoantibodies has been believed since elevated levels of neutrophil-associated IgG (NAIgG) have been described. However, no data exists to characterize the nature of NAIgG and show NAIgG is an anti-neutrophil autoantibodies. We investigated whether the elevated NAIgG in these patients consists of anti-neutrophil autoantibodies. The NAIgGs of 91 patients with autoimmune disorders including 50 patients with idiopathic thrombocytopenic purpura, 13 patients with systemic lupus erythematosus, 11 patients with Hashimoto's thyroiditis and 10 patients with Graves' disease were analyzed. The level of NAIgG was high in 36 of 91 patients. Elution studies were performed to determine whether NAIgG has a nature of autoantibodies. In model experiments, the ether elu-ate from neutrophils sensitized with neutrophil-specific alloantibody (anti-NA2) reacted with donor neutrophils, whereas the eluates from those with model immune complexes (ICs) failed. These data indicated that the ether elution technique is useful to determine whether NAIgG consists of anti-neutrophil autoantibodies. The NAIgG on patient's neutrophils was eluted with ether and the reactivity of the eluate with normal neutrophils was investigated. The eluates from 34 of 36 patients with various autoimmune disorders with elevated NAIgG level failed to react with donor neutrophils. These data indicated that the elevated NAIgG in the majority of these patients did not consist of anti-neutrophil autoantibodies, but possibly of ICs.

Matrix Solid Phase Dispersion (MSPD) Isolation and Liquid Chromatographic Determination of Clorsulon in Milk

Abstract A method for the isolation and liquid chromatographic determination of the anti-parasitic drug clorsulon in milk is presented. Milk samples (0.5 g) were blended with 2 grams of C-18 (octadecylsilyl-derivatized silica column packing material). A column was made from the C-18/milk matrix and first washed with hexane. The clorsulon was then eluted from this column with ethyl ether. The ether eluate was cleaned up by Florisil solid phase extraction, and clorsulon was subsequently determined by liquid chromatography with UV detection. The overall recovery of clorsulon from milk spiked at 50–200 ppm was 93.0&with a coefficient of variation of 5.6 & The MSPD method and a solid phase extraction method used by the FDA gave comparable values for milk containing incurred clorsulon residues.

Elution of Anti-Zwa (-P1^A1) from Autologous Platelets after Normalization of Platelet Count in Post-Transfusion Purpura

In two patients suffering from post-transfusion purpura, anti-Zw^a was demonstrated in ether eluates from autologous platelets harvested during the remission phase and after normalization of the platelet count. In both patients, platelet-associated immunoglobulin (PAIg) was demonstrated during the acute phase. PAIg disappeared concomitantly with recovery and, thus, seems to be associated with the thrombocytopenia. These data support the assumption that immunocomplexes are adsorbed nonspecifically to the platelets and cause destruction of autologous platelets lacking the corresponding antigen. An association between the IgG3 subclass of anti-Zw^a antibodies and the destruction of autologous platelets was also seen.

Evaluation of the manual hexadimethrine bromide (Polybrene) technique in the investigation of autoimmune hemolytic anemia

The use of the direct manual hexadimethrine bromide (Polybrene) test (DPT) in the investigation of patients for autoimmune hemolytic anemia (AIHA) was evaluated. Seventy-nine blood samples from 68 patients were tested. A direct antiglobulin test (DAT) using monospecific reagents and the DPT were performed, and a concentrated ether eluate was tested. The DAT was positive in 62 (78%) of 79 patients and negative in 17 (22%). There is a good correlation among DAT, eluate, and DPT in demonstrating the presence of immunoglobulin on the red cell surface. In contrast, the DPT does not detect C3d and is often negative in cases of AIHA in which C3d alone is demonstrated by the DAT. In DAT-negative cases, DPT results correlated with reactive eluates. However, in four cases of steroid-responsive, DAT-negative hemolytic anemia, the DPT supported the diagnosis of AIHA when the eluate did not react. The DPT is a useful additional screening test for the investigation of AIHA, but it is not recommended as a replacement for either eluate testing or the DAT.

Demonstration of platelet antigens that bind platelet‐associated autoantibodies in chronic ITP by direct immunoprecipitation procedure

Platelet antigens that bind platelet-associated autoantibodies in chronic idiopathic thrombocytopenic purpura (ITP) were demonstrated using a direct immunoprecipitation procedure. ITP platelets, with bound autoantibodies, were radiolabelled and solubilized, and then platelet antigen-antibody complexes adsorbed to protein A-bearing Staphylococcus aureus were analysed by 7.5% sodium dodecyl sulphate, polyacrylamide gel electrophoresis (SDS-PAGE). Direct immunoprecipitation demonstrated the presence of platelet-associated autoantibodies against glycoprotein (GP) IIb/IIIa in four of six ITP patients with an intensive band corresponding to platelet-associated IgG. These results were confirmed by indirect immunoprecipitation using ether eluates from two ITP patients. In addition, only direct immunoprecipitation demonstrated the presence of autoantibodies against an unidentified protein having a molecular mass of 56 kDa in three of the six patients. These three ITP patients having autoantibodies against GP IIb/IIIa and against the 56 kDa protein were studied after splenectomy. Two patients, showing disappearance of autoantibodies against these antigens, attained a complete remission, and one patient, with autoantibodies against the 56 kDa protein despite splenectomy, attained only partial remission. These data suggest that autoantibodies against GP IIb/IIIa and against the 56 kDa protein may play a role in platelet destruction in some ITP patients.

Simultaneous gas chromatography of volatile and non-volatile carboxylic acids as tert.-Butyldimethylsilyl derivatives

Solid phase extraction with subsequent ion pair formation and silylation was investigated for the simultaneous trace enrichment of volatile and non-volatile carboxylic acids from complex aqueous samples. The solid phase extraction of acids was performed using Chromosorb P as the solid sorbent. The ether eluate was treated with triethylamine. The resulting triethylammonium salts of the acids were converted to stable tert.-butyldimethylsilyl (TBDMS) derivatives, which were analyzed by gas chromatography (GC) and GC-mass spectrometry. The characteristic M - 57 ions in the mass spectra of TBDMS derivatives enabled rapid identification of acids. The application of the method to the organic acid profiling of urine and saliva samples is demonstrated.

Thrombocytopenia associated with gold therapy: a drug-induced autoimmune disease?

We studied 13 patients with rheumatoid arthritis (RA) and gold-induced thrombocytopenia. Platelet-specific autoantibodies of the IgG and often also of the IgM class were detected by immunofluorescence on the patient's platelets and in ether eluates from these platelets. In nine patients we also detected autoantibodies in the serum. The antibodies were unreactive with platelets from patients with Glanzmann's disease in most cases, and were not EDTA dependent. Thus, they had the serological characteristics of true autoantibodies. The reaction of the antibodies with platelets was not influenced by the addition of extra gold. By atomic absorption spectrophotometry we found that the ether eluates, which were often strongly reactive with donor platelets, were free of gold. This indicated that the autoantibodies in the thrombocytopenic patients were not dependent on gold for their reaction. The possibility is raised that gold treatment of rheumatoid arthritis patients induces or enhances the formation of platelet-specific autoantibodies, and that gold-induced thrombocytopenia is a drug-induced autoimmune disease.

Resolution of red cell compatibility testing problems in patients receiving anti-lymphoblast or anti-thymocyte globulin.

Passively acquired hemagglutinating antibodies may be detected in the serum of patients receiving horse anti-lymphoblast globulin (ALG) or anti-thymocyte globulin (ATG). Thirty-seven patients receiving ALG following renal transplantation were studied. Eight patients monitored daily all developed positive direct antiglobulin tests (DAT) and positive red cell antibody screening tests. Fifteen of 32 recipients developed red cell antibodies reactive at room temperature in saline, 4 of 32 in albumin at 37 degrees C, and 33 of 37 in the antiglobulin test. Horse globulin was detected on the red cells of all six recipients tested with rabbit anti-horse globulin. Ether eluates prepared from the red cells of 20 patients showed no specificity for common red cell antigens. Anti-human globulin (AHG), absorbed with ALG-coated red cells to remove the component in the AHG which was crossreacting with horse globulin, was used successfully for antibody screening and identification, direct antiglobulin testing, and/or the antiglobulin crossmatching of 27 ALG and ATG recipients, including five with red cell alloantibodies.

Hydrocarbons of Scalp Hair Lipids from Teenage Males

AbstractLipids extracted with ethyl ether from 2 pools of hair each from Caucasian (ages: 13–14 and 15–18 yr) and Black teenagers (17 and 18 yr) were saponified and the unsaponifiable portions chromatographed over alumina toward concentration of the hydrocarbons. Of these, the paraffins were further enriched by use of silica gel columns, the petroleum ether eluate containing the saturated members; elution with solvents of increasing polarity gave rise to cuts high in squalene together with small amounts of other olefins. Temperature‐programmed gas chromatography was applied to the determination of the saturated hydrocarbon peaks, the branched and cyclic components which occurred at far lower levels, being ascertained by a heated pre‐column containing Linde Molecular sieves (5 Å). Then‐paraffins displayed peaks of C15‐C34, with several of up C45 being more conspicuous with the Black pools. The present preliminary data point possibly to a higher total hydrocarbon content in the Blacks especially, as reflected in the elevated saturated hydrocarbon contents. In terms of μg/g hair, the recoveries of squalene were 1642 and 1746 of a total of 1870 and 1987 for the respective white pools while the corresponding values were 2273 and 1640 of overall yields of 6935 and 3656 for the Black hair. The ratios of squalene to nonsqualene hydrocarbons were 7.2 for the Caucasian pools and 0.5 and 0.8 for the Black teenagers.

Inhibition of metabolic cooperation by cigarette smoke condensate and its fractions in V-79 Chinese hamster lung fibroblasts.

This study was performed to determine the usefulness of the intercellular metabolic cooperation assay for analysis of a complex mixture and to compare the results obtained with previously conducted in vivo tumor promoter assays. One hundred 2R1 cigarettes were smoked according to Federal Trade Commission guidelines and the resulting condensate was separated into a water/methanol-soluble fraction (which was further partitioned into acidic and basic components) and an organic solvent-soluble fraction (which was then chromatographed on silicic acid with petroleum ether, benzene/petroleum ether, benzene, ether, and methanol). The following fractions were positive in the metabolic cooperation assay (in decreasing order of activity): organic solvent-soluble, acidic, whole condensate, and water/methanol-soluble fractions as well as the ether, benzene, and benzene/petroleum ether eluates. The basic fraction and the petroleum ether and methanol eluates were negative. In general, the metabolic cooperation assay results were comparable to previously published results obtained on mouse skin.

Autoantibodies Mimicking Anti-Jk^b plus Anti-Jk3 Associated with Autoimmune Hemolytic Anemia in a Primipara Who Delivered an Unaffected Infant

A serum sample from a nontransfused 2 5-year-old Caucasian primipara contained weak anti-Jk^b plus anti-Jk3. The direct antiglobulin test on the patient’s red cells was strongly positive. Anti-Jk^b was recovered in a heat eluate. An ether eluate contained anti- Jk3. Her red cells typed as Jk(a-b+)Jk:3. The anti-Jk^b and anti-Jk3 reactivity was completely absorbed both by red cell samples lacking and red cells possessing the corresponding antigens, indicating these antibody specificities to be of the mimicking variety. At 41 weeks gestation she delivered a normal, healthy infant with no detectable serum or cell bound antibody.

Fluorometric Determination of Methylergonovine Maleate and Ergonovine Maleate in Tablets and Injections

A column cleanup, followed by a shakeout and fluorometric determination, has been developed to determine methylergonovine maleate and ergonovine maleate in tablets and injections. The ether eluate is extracted with tartaric acid solution. An aliquot is diluted with sodium tartrate solution, and this solution is excited at 325 nm. The resulting fluorescence is measured at 432 nm. Results obtained using this method compare favorably with those from the official NF XIV procedure and a semiautomated procedure. Recoveries of 100 and 99% were obtained from one sample each of spiked excipient tablets of methylergonovine maleate and ergonovine maleate, respectively.

Schnellmethode zur Bestimmung des �lanteils in Lecithin

A rapid method for routine determination of oil in commercial lecithins and similar phospholipid samples has been worked out. This based on the observation that under the described experimental conditions 1 g of phospholipids is completely adsorbed on 45 g silica gel which has previously been disactivated by the addition of 15% water. The lecithin sample is filtered in ethereal solution through a column filled with disactivated silica gel which is subsequently washed with a little ether. The combined ether eluates are evaporated to dryness invacuo and the residue weighed. This residue is the oil part of the sample and is constituted of mono-, di-, and triglycerides, free fatty acids, sterols and their derivatives. The duration for one such determination is about 20 min.

Evidence of platelet complement-fixing and lymphocytotoxic anti-A-1 antibodies.

3 human antisera exhibiting non HL-A specific antibody were studied in micro-complement fixation with platelets and micro-lymphocytotoxicity. Screening studies as well as absorption and elution studies with platelets, lymphocytes and erythrocytes revealed an antibody activity associated with blood group A-1. Within blood group A-1, a subpopulation of A-1 donor cells- provisionally called "weak A-1" - was defined, which had a minor ability for complement-fixing and lymphocytotoxic A-1-antibody absorption. Contrary to HL-A specific antibodies, acid eluates from platelets of these 3 sera were always negative whereas heat and ether eluates gave positive results. From neutralization studies and studies on the hemolytic activity against A-1 erythrocytes it was concluded, that the A-1-specific antibodies probably are immune antibodies belonging to the IgG class of immunoglobulins.