bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of biological fluids for the rapid diagnosis of potentially lethal inherited disorders of human purine and pyrimidine metabolism
Authors: Morris George S. , Simmonds H. Anne , Davies Phillip M. 
Published: May 2005

AbstractInherited purine and pyrimidine disorders may be associated with serious, sometimes life‐threatening consequences. Early and accurate diagnosis is essential. Difficulties encountered when using existing high pressure liquid chromatographic (HPLC) methods led to the development of an improved method based on prior fractionation of urine. The advantages are as follows. 1. Production of fingerprints demonstrating altered urinary excretion patterns characteristic of any one of ten different disorders, in 30 minutes. 2. Positive identification and quantification by comparison with established methods (using conventional chromatography, electrophoresis and UV spectrophotometry) in addition to specific retention times and characteristic UV absorbance ratios at two separate wavelengths (245 and 280 nm) by HPLC. 3. Direct analysis of all the purines and pyrimidines normally found in human body fluids as well as identification of abnormal compounds. 4. Short time between successive analyses while maintaining excellent resolution between compounds of interest and column longevity. 5. Improved separation of the different adenine‐based compounds encountered in some disorders, plus demonstration of potential interference by dietary or drug metabolites. 6. Applicability to the monitoring of therapy involving a variety of different purine and pyrimidine analogues.Particular attention should be paid to sample preparation. Plasma profiles will confirm the diagnosis in some, but not all, of these disorders.
Metabolic studies of explosives. 5. Detection and analysis of 2,4,6‐trinitrotoluene and its metabolites in urine of munition workers by micro liquid chromatography/mass spectrometry
Authors: Yinon J. , Hwang D.‐G. 
Published: May 2005

AbstractMetabolites of 2,4,6‐trinitrotoluene (TNT) were found in the urine of a group of TNT munition workers. The urine extracts were analysed by micro liquid chromatography/mass spectrometry. The metabolites found included 2‐amino‐4,6‐dinitrotoluene, 4‐amino‐2,6‐dinitrotoluene, 2,4‐diamino‐6‐nitrotoluene, 2,6‐diamino‐4‐nitrotoluene and untransformed TNT. The detection limit of the metabolites in urine was 0.1 ng/ml for 20 ml urine samples.
Automated and routine liquid chromatographic analysis of antiepileptic drugs
Authors: Pang Chi‐Pui , Ho Kwok‐Chu , Cheung Chi‐Keung 
Published: May 2005

AbstractWe describe an optimized automated liquid Chromatographic method for simultaneous measurement of primidone, phenobarbitone, phenytoin, carbamazepine and clonazepam. A Waters Tri‐Module automation system is used and it provides direct read‐out of results after chromatography. A one‐step extraction with ethyl acetate is used to extract the drugs from 100 μL serum samples. We use an isocratic mobile phase and monitor the column effluent at 210 nm. Drug levels as low as 5 μmol/L can be detected. The within‐run CV's range from 1.4 to 2.7%, and the between‐run CV's range from 5.2 to 6.1%. Analytical recovery is in the range from 94–108%. The method compares favourably with the enzyme multiple immunoassay technique for routine antiepileptic drugs monitoring, in accuracy, efficiency and cost‐effectiveness.
Determination of galactose in human plasma by HPLC with electrochemical detection
Authors: Watanabe Noriyuki , Kawasaki Seiji 
Published: May 2005

AbstractGalactose in plasma from patients with hepatic diseases who had undergone low level galactose infusion was determined by using HPLC with electrochemical detection (LCEC). Agreement between galactose concentration determined by the LCEC and a fluorometric method was remarkably good at moderate levels of galactose in plasma. However, the fluorometric method is not suitable for samples containing very small amounts of galactose (blood from hepatic veins) and even for a few samples at moderate galactose content (blood from peripheral veins), suggesting the presence of an endogenous interference. There was no interference for the quantitation of galactose by the LCEC method, by virtue both of the specificity involved in the electrochemical detection and the separation by liquid chromatography. The detection limit of the LCEC method was 0.4 mg galactose/L blood.
The determination of cysteamine in physiological fluids by HPLC with electrochemical detection
Authors: Kelly Michael J. , Perrett David , Rudge Susan R. 
Published: May 2005

AbstractCysteamine, an amino thiol, was separated by rapid isocratic cation exchange chromatography and detected by electrochemical oxidation at a platinum electrode maintained at +0.45 V relative to an Ag/AgCl reference electrode. Eluent pH and electrode working potentials were optimized and the effects of alternative buffers and organic modifiers have been examined. On column sensitivity for cysteamine was 1.5 pmol at a signal‐to‐noise ratio of 5. Although the specificity was good, plasma samples required maximal sensitivity whereas urine samples required greater selectivity, which was achieved by use of lower working potentials. Cysteamine concentrations were determined in serial samples of plasma and urine from volunteers who had received a single oral dose of 200 mg of the drug. Cysteamine was rapidly oxidized in vivo, and detection required prior reduction with dithiothreitol before analysis.
Determination of 4‐methylpyrazole in plasma using solid phase extraction and HPLC
Authors: Diczfalusy Ulf , Eklöf Roland 
Published: May 2005

AbstractA rapid method for the determination of 4‐methylpyrazole in plasma is described. Internal standard (3‐methylpyrazole) is added to the plasma which is subsequently applied to a BondElut SCX column. After washing the column the 3‐ and 4‐methylpyrazoles are eluted with a phosphate buffer and analyzed by isocratic reversed‐phase high performance liquid chromatography with UV detection. The concentration of 4‐methylpyrazole is calculated from the 4‐methylpyrazole/3‐methylpyrazole peak high ratio. The method is linear between 2.5 and 100 μmol/L with a within‐day precision (CV) of 2.2% (n = 10) and a day‐to‐day precision of 2.8% (n = 30). The sensitivity is sufficient for analysis of plasma levels in the low micromolar range.
Structural characterization by chromatographic profiling of the oligosaccharides of human immunodeficiency virus (HIV) recombinant envelope glycoprotein gp120 produced in chinese hamster ovary cells
Authors: Mizuochi Tsuguo , Spellman Michael W. , Larkin Margot , Solomon Julie , Basa Louisette J. , Feizi Ten 
Published: May 2005

AbstractThis report together with the paper by T. Mizuochi, M. W. Spellman, M. Larkin, J. Solomon, L. J. Basa and T. Feizi (1988) Biochem. J. 254, 599–603 describes the structural elucidation of the N‐linked oligosaccharides of the HIV envelope glycoprotein, gp120 (cloned from the HTLV‐III B isolate and expressed as a secreted fusion protein after transfection of Chinese hamster ovary cells), which is known to bind with high affinity to human T4 lymphocytes. Oligosaccharides were released from peptide by hydrazinolysis, fractionated by paper electrophoresis, high performance lectin affinity chromatography and Bio‐Gel P‐4 column chromatography, and their structures determined by sequential exoglycosidase digestions in conjunction with methylation analysis. The glycoprotein was found to be unique in its diversity of oligosaccharide structures. These include high‐mannose type and hybrid type, as well as four categories of complex type chains: mono‐, bi‐, tri‐ and tetra‐antennary, with or without N‐acetyllactosamine repeats, and with or without a core region fucose residue. Among the sialidase‐treated oligosaccharides no less than 29 structures were identified as follows:
magnified image
where G=galactose; GN=N‐acetylglucosamine; M=mannose; F=fucose; ±=residues present in a proportion of chains. The actual number of oligosaccharide structures is much greater since before desialylation there was evidence that among the hybrid and complex type chains all but 6% contained sialic acid at the C‐3 position of terminal galactose residues, and partially sialylated forms of the bi‐ and multiantennary chains were present.
Solid phase extraction and HPLC determination of spiramycin in plasma and vitreous concentrations
Authors: Carlhant D. , Le Bot M. A. , Guedes Y. , Riche C. , Mimouri F. , Colin J. , Berthou F. 
Published: May 2005

AbstractA method for extracting spiramycin by an octadecylsilica cartridge is described for plasma or vitreous samples. The macrolide antibiotic is then measured by reversed‐phase HPLC with UV detection. The limit of detection is estimated to be 50 ng/mL. The coefficient of variation for the procedure is 6.1% and 5.2% for the range of concentrations 0.2 μg/mL and 10 μg/mL respectively. By this method, pharmokinetic profiles were performed for five adult patients. Spiramycin could be accurately measured in the vitreous humour, allowing the determination of antibiotic at its site of action.
A simplified method for the preparation of wga‐sepharose 4B and its use in the purification of MN blood group antigens
Authors: Shimin Zhang , Jianxin Li , Yaomei Wei , Zhiming Yang 
Published: May 2005

AbstractA simplified method for the preparation of wheat germ agglutinin(WGA)‐Sepharose 4B by coupling highly purified WGA, prepared by improved affinity chromatography, with BrCN activated Sepharose 4B in a solution of high carbonate buffer is described. The amount of WGA linked to Sepharose 4B was 82.40% (3.07 mg WGA per ml Sepharose 4B). MN blood group antigens of human erythrocyte membranes purified with WGA‐Sepharose 4B affinity chromatography showed a single band on sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE). The yield of the antigens from 400 mL fresh blood was 32–40 mg. The WGA‐Sepharose 4B column could be used several times without loss of activity.
High‐performance liquid chromatography/chemiluminescence determination of biological thiols with n‐[4‐(6‐dimethylamino‐2‐benzofuranyl)phenyl]maleimide
Authors: Nakashima Kenichiro , Umekawa Chiemi , Nakatsuji Shin'Ichi , Akiyama Shuzo , Givens Richard S. 
Published: May 2005

AbstractThe peroxyoxalate chemiluminescence detection of biological thiols combined with high‐performance liquid chromatography (HPLC) is described. SH groups of the thiol compounds including glutathione (GSH), cysteine, N‐acetylcysteine, cysteamine, and D‐penicillamine were labelled with N‐[4‐(6‐dimethylamino‐2‐benzofuranyl)phenyl]maleimide (DBPM), a specific fluorogenic reagent for SH group. The labelling reaction was carried out at 60°C for 30 min and at pH 8.5 and a sample of the resulting reaction mixture was subjected to HPLC. Five kinds of labelled thiols were separated within 12 min on ODS‐80 column (150 × 4.6mm ID; 5 μm) and detected in the ranges from 500 fmol to 2 pmol/100 μL (cysteamine and N‐acetylcysteine), to 3 pmol/100 μL (cysteine) and to 5 pmol/100 μL (GSH and D‐penicillamine). The lower detection limits were from 7 fmol (cysteamine) to 113 fmol (GSH) per 100 μL (S/N = 2). The method was applied to the determination of thiols in a rat liver. The amounts of glutathione and cysteine were 1.23±0.15 μmol/g (n = 5) and 0.15±0.04 μmol/g (n = 5), respectively.
Rapid assay of β‐galactosidase and sialyltransferase by lectin affinity high performance liquid chromatography with fluorescence detection
Authors: Harada Hiroshi , Ueno Yasushi , Kamei Masugu , Ohura Reiko , Tanabe Noriko , Uchida Yasuko , Koyama Fumihiro , Yamaguchi Takashi 
Published: May 2005

AbstractFluorescein isothiocyanate (FITC)‐labelled asialotransferrin and pyridyl aminated oligosaccharides were prepared from asialotransferrin and human milk using affinity chromatography and high performance liquid chromatography (HPLC), respectively. These substances were incubated with galactosidase or sialyltransferase and then examined by lectin affinity HPLC. The elution patterns changed according to the period of incubation and amount of enzyme. This analytical method using lectin affinity HPLC with fluorescence labelled glycoprotein or oligosaccharides as the substrates has great value for detecting these enzyme under the same chromatographic conditions. In addition, differences were noted in the activity of β‐galactosidase toward oligosaccharides having the Gal β(1 → 3)GlcNAc or Gal β(1 → 4)GlcNAc structure at reducing termini.
Rapid and sensitive determination of β‐phenylethylamine in animal brains by high performance liquid chromatography with fluorometric detection
Authors: Taga Chiaki , Tsuji Motohiro , Nakajima Teruo 
Published: May 2005

AbstractA reversed phase HPLC method with fluorometric detection for the analysis of β‐phenylethylamine has been developed using p‐methoxyphenylethylamine as an internal standard. Two columns, containing 200 μL of Dowex 50‐X8 and Amberlite CG‐50 respectively, were used to prepare a fraction containing β‐phenylethylamine. The recoveries of β‐phenylethylamine and p‐methoxyphenylethylamine were 53.9 ± 9.4% and 68.1 ± 12.4%, respectively, and elution profile of p‐methoxyphenylethylamine was sufficiently well correlated with that of β‐phenylethylamine. Regional distributions of β‐phenylethylamine in rat and mouse brains were determined. The highest concentrations were found in hypothalamus and hippocampus in both animals.
Lactoferrin from human breast milk and from neutrophil granulocytes. Comparative studies of isolation, quantitation, characterization and iron binding properties
Authors: Bezwoda W. R. , Mansoor N. 
Published: May 2005

AbstractThe isolation and properties of lactoferrin from human breast milk and from neutrophilic granulocytes were investigated. Human breast milk lactoferrin was purified by means of heparin‐sepharose or Cibacron Blue affinity chromatography. Quantitative recovery using these two methods was comparable but Cibacron Blue affinity chromatography allowed for isolation of a more homogenous protein. Lactoferrin could only be isolated from human neutrophilic granulocytes by sequential use of antibody affinity followed by non‐specific affinity chromatography. Both breast milk lactoferrin and granulocyte lactoferrin were separated into apo and iron‐rich species by SDS polyacrylamide gel chromatography. Iron binding is accompanied by a conformational change in tertiary structure associated with more rapid electrophoretic migration. The isoelectric point of both human breast milk lactoferrin and human granulocyte lactoferrin is 5.5 – 6.2. Both types of lactoferrin have similar iron binding properties with release of iron from the one binding site occurring at pH 5.2 – 6.0 while the other binding site holds on to iron down to pH 3.6 – 3.2. Despite the high affinity for iron the percentage saturation of native lactoferrin is low, that for breast milk lactoferrin averaging 12 – 25% and that for granulocyte lactoferrin < 10%.
Purification of rat liver soluble catechol‐O‐methyltransferase by high performance liquid chromatography
Authors: Korkolainen Tapio , Nissinen Erkki 
Published: May 2005

AbstractThe soluble form of catechol‐O‐methyltransferase (EC 2.1.1.6.) from rat liver was purified to homogeneity by high‐performance anion‐exchange chromatography and high‐performance gel‐filtration chromatography. The specific activity of the final pool was 270 U/mg protein. The purification was 1180‐fold and recovery of the enzyme activity was 15%. During this rapid and gentle purification there were no problems with loss of activity, and the estimated half life of the final purified enzyme pool was 5.5 days at +4°C. The only additive used was phenylmethylsulfonylfluoride in the homogenizing buffer.
Evidence for the overestimation of molecular masses of proteins after chemical modification and chemical crosslinks on sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS‐PAGE)
Authors: Richard Claude , Han Kia‐Ki , Yang Hui‐Ling , Zhu De‐Xu , Balduyck Malika , Mizon Jacques 
Published: May 2005

AbstractHuman trypsin inhibitor (home prepared), lactalbumin, trypsinogen, carbonic anhydrase, and bovine serum albumin were submitted to succinylation and their molecular masses were determined by SDS‐PAGE according to the method of Weber and Osborn (1969 J. Biol. Chem. 244, 4406) before and after chemical modification. High estimates of their molecular masses were obtained. The monomer and dimer of arrowhead inhibitor proteinase‐B (Chinese vegetable legume) obtained after chemical crosslink(s) were also submitted to SDS‐PAGE and their apparent molecular masses were also determined and compared to the native arrowhead inhibitor proteinase‐B. Abnormally high estimates of their molecular masses were obtained. Our results agree with those in the literature.
Unconjugated methoxylated catecholamine metabolites in human saliva. Quantitation methodology and comparison with plasma levels
Authors: Drebing Carla J. , Freedman Robert , Waldo Merilyne , Gerhardt Greg A. 
Published: May 2005

AbstractA newly developed method for the simultaneous extraction and quantitation of the unconjugated levels of the catecholamine metabolites vanilmandelic acid (VMA), 3‐methoxy‐4‐hydroxyphenylethylene glycol (MHPG) and homovanillic acid (HVA) in plasma by high performance liquid chromatography with electrochemical detection was modified and applied to studies of human saliva. The assay had a mean coefficient of variation under 3% for each of the metabolites. Levels of plasma VMA, MHPG and HVA were measured in 28 normal subjects and compared to their saliva levels, obtained before and after stimulation by mastication. Significant correlations were found between plasma and saliva MHPG and HVA, but there was no correlation between plasma and saliva VMA. Salivary MHPG and HVA can be reproducibly assayed and may be useful tools for indications of changes in central and peripheral catecholamine metabolism.
Isolation of glycoprotein D from herpes simplex virus type 1 by gel filtration high performance liquid chromatography
Authors: McGarry Thomas J. , Al‐Ahdal Mohammed N. 
Published: May 2005

AbstractRabbit kidney (RK‐13) and human jejunum and ileum (I‐407) cells infected with herpes simplex virus type 1, strain F, were radiolabelled with [14C]glucosamine or [35S]methionine for 24 h. The cells were extracted with 1% Triton X‐100 and the extracts were separated by gel filtration high performance liquid chromatography. Monoclonal antibody immunoprecipitation of the fractions collected from the column revealed a monomeric glycoprotein D (gD) of 52 – 56 000 molecular weight from RK‐13 cells and two monomeric forms of gD, 54 000 and 58 000 molecular weight, from I‐407 cells. Densitometry scanning of the autoradiograms from SDS‐PAGE showed gD from the RK‐13 host cells to be 98.7% pure with the [35S]methionine label and 97.0% pure with the [14C]glucosamine. On the other hand, gD from the I‐407 host cells was only 78.6% with the [35S]methionine label and 96% pure with the [14C]glucosamine. This method could provide a means for the isolation of native gD for structural and immunological studies.
Multidimensional chromatographic separation of estrogen receptors
Authors: Raubenheimer J. , van der Walt L. A. 
Published: May 2005

AbstractAnalyses of estrogen and progesterone receptors in biopsies of breast carcinoma play a vital role in the selection of patients likely to respond to hormone manipulation. Sucrose density gradient centrifugation has been the reference method in the determination of estrogen receptors in human breast carcinoma cytosols. To reduce assay time and circumvent prolonged manipulation of labile receptor preparations, high performance liquid chromatography techniques in the size‐exclusion and ion‐exchange modes were compared as potential alternate methods for the rapid separation of receptor isoforms. Multidimensional analyses were performed by reapplying estrogen receptor isoforms obtained from high performance size‐exclusion and ion‐exchange chromatography to sucrose density gradients and vice versa. This confirmed that the estrogen‐binding components identified by high performance liquid chromatography appear to correspond to estrogen receptor species from sucrose density gradients.
Capillary gas chromatography/negative ion chemical ionization mass spectrometry for the quantification of bile acids including 1β‐hydroxylated and unsaturated bile acids in serum and urine
Authors: Miyara Takako , Shindo Noriko , Tohma Masahiko , Murayama Kimie 
Published: May 2005

Abstract12 bile acids, including 1 β‐hydroxylated and unsaturated bile acids, have been quantified by capillary gas chromatography/negative ion chemical ionization mass spectrometry, using the trimethylsilyl(TMS) ether derivatives of bile acid pentafluorobenzyl(PFB) esters. The analysis time is 12 min and the minimum measurable amount is 100 fg for each bile acid. Bile acids in 200 μL of serum and 50 μL of urine from healthy human adults were measured. These small sample sizes enhance the practicality of using this method as a screening test for bile acids in the serum and urine of human infants, where small sample size is a major problem.
Simultaneous detection and quantitation of O6‐monoacetylmorphine, morphine and codeine in urine by gas chromatography with nitrogen specific and/or flame ionization detection
Authors: Vu‐Duc Trinh , Vernay André 
Published: May 2005

AbstractIt is of importance to differentiate heroin intake from the absorption of opiate‐containing pharmaceuticals or opiates from other sources. A method for the routine determination of O6‐monoacetylmorphine (6‐MAM), the specific metabolite of heroin in human urine, by gas chromatography and classical detectors without having recourse to gas chromatography/mass spectrometry‐selected ion mode (GC/MS‐SIM) is described. With dual detection by nitrogen selective and flame ionization detectors, the limits of detection for 6‐MAM were determined to be 2 ng/mL and 4 ng/mL urine for a 10 mL sample. When applied to urines preliminarily screened for opiates, the results appeared consistent in comparison with those obtained by GC/MS‐SIM. The method was also developed for the simultaneous quantitative analysis of morphine and codeine. The linearity was tested up to 600 ng/mL for the three compounds of interest 6‐MAM, morphine and codeine and their absolute recoveries were 76%, 78%, 75% respectively.
Rapid detection of extended ganglio‐series gangliosides with terminal GalNAcβl‐4Gal sequence on high performance thin layer chromatography plates
Authors: Müthing Johannes , Ziehr Holger 
Published: May 2005

AbstractThe mouse monoclonal antibody 2D4, which recognizes the terminal GalNAcβ1‐4Gal‐disaccharide of GgOse3Cer and GgOse5Cer, was used for the detection of ganglio‐series gangliosides. The method involves separation of gangliosides on thin layer chromatography plates, followed by silica gel fixation, Arthrobacter ureafaciens neuraminidase treatment and final immunostaining of desialylated gangliosides with the monoclonal antibody 2D4. Both neuraminidase and the hybridoma 2D4 producing the specific monoclonal antibody are commercially available and therefore accessible to all researchers working in this field.Gangliosides from mouse T lymphocytes and the mouse T cell lymphoma YAC‐1 have been used as examples. This technique may be used for fast screening of gangliosides with the GgOse5Cer core structure which have been described as T cell markers, antigens in human neuronal disease and receptors for certain pathogenic bacteria.