bluuebunny/crossref_metadata_2025_split huggingface dataset:
Peripheral nerve abnormality in multiple sclerosis
Authors: Pollock Martin , Calder Christopher , Allpress Stephen 
Published: May 2005

AbstractBiopsy specimens of sural nerve from 10 patients with multiple sclerosis (MS), of whom only 1 was severely disabled, were assessed by morphometric techniques and compared to nerves from age‐matched controls. The frequency of abnormal teased fibers was increased in MS nerve, with many intenodes showing at least a 50% reduction in myelin thickness. Myelinated nerve fiber densities were not significantly different in MS and control nerves. Regression analysis of axonal area on number of myelin lamellae indicated a generalized reduction of myelin lamellae in this disorder. It is suggested that peripheral myelin may be involved in multiple sclerosis.Supported by the New Zealand Neurological Foundation, the Medical Research Council, and the National, Otago, and Canterbury Multiple Sclerosis Societies.
“Inverse latent” macro square‐wave jerks and macro saccadic oscillations
Authors: Dell'Osso L. F. , Abel L. A. , Daroff R. B. 
Published: May 2005

AbstractA patient recovering from an acute encephalopathy demonstrated several ocular motor disturbances reflecting cerebellar and brainstem dysfunction. Two of these, macro square‐wave jerks and macro saccadic oscillations, have never been reported in the same patient. The macro square‐wave jerks disappeared with monocular viewing, a previously undescribed “inverse latent” characteristic.
Diencephalic syndrome and von recklinghausen's disease
Authors: Adornato Bruce , Berg Bruce 
Published: May 2005

AbstractTwo infants with von Recklinghausen's disease developed signs and symptoms of the diencephalic syndrome. Pathological examination confirmed the presence of hypothalamic tumors in both. The concurrence of these two entities, although previously unreported, is not unexpected given the incidence of intracranial tumor in von Recklinghausen's disease and the dinecephalic syndrome.
The effect of two bisphosphonates on human neutrophil chemiluminescence and myeloperoxidase activity
Authors: Kowolik M. J. , Hyvönen P. M. , Sutherland R. , Raeburn J. A. 
Published: May 2005

AbstractIn order to assess the importance of chlorine in a drug molecule as an influence on myeloperoxidase‐mediated inflammatory cell functions, the effect of the chlorinated bisphosphonate, clodronate, on human neutrophil chemiluminescence and myeloperoxidase (MPO) activity was compared to the non‐chlorinated structural analogue, etidronate. The results suggested that the presence of chlorine may be important to the enhancement of MPO activity. In addition both drugs manifested low toxicity and both of these observations may have relevance to host defence.
Chemiluminescent assay of enzymes using proenhancers and pro‐anti‐enhancers
Authors: Kricka Larry J. , Schmerfeld‐Pruss Deborah , Edwards Brooks 
Published: May 2005

AbstractEnhanced chemiluminescent assays for hydrolase enzymes have been developed using proehancer and pro‐anti‐enhancer substrates. Alkaline phosphatase is measured using disodium para‐iodophenyl phosphate (proenhancer) which is converted to para‐iodophenol and this in turn enhances the light emission from the horseradish peroxidase catalysed chemiluminescent oxidation of luminol by peroxide. An alternative strategy uses para‐nitrophenyl phosphate which is converted by alkaline phosphatase to para‐nitrophenol which inhibits the enhanced chemiluminescent reaction. The detection limit for the enzyme using the proenhancer and pro‐anti‐enhancer assays was 100 attomoles and 1 picornole, respectively. The proenhancer strategy was effective in assays for beta‐D‐galactosidase, beta‐D‐glucosidase and aryl sulfatase. A limited comparison of the proenhancer and a conventional colorimetric assay for an alkaline phosphatase label in an enzyme immunoassay for alpha‐fetoprotein showed good agreement.
Attenuation of 4‐I‐phenol‐enhanced chemiluminescence by non‐enhancer phenols
Authors: Candy Thomas E. G. , Jones Peter 
Published: May 2005

AbstractThe intensity of 4‐I‐phenol‐enhanced chemiluminescence from the luminol‐H2O2‐horseradish peroxidase system is markedly attenuated in the presence of low concentrations of non‐enhancer phenols. Under the conditions studied, the effect is not associated with competition between 4‐I‐phenol and non‐enhancer phenol for the enzyme intermediates, Compounds I and II, but involves a competition between non‐enhancer phenol and luminol most probably for the 4‐I‐phenoxy radical.
Fluorescence high performance liquid chromatographic determination of 3α‐hydroxysteroids in urine of 21‐hydroxylase deficiency
Authors: Kawasaki Takao , Maeda Masako , Tsuji Akio 
Published: May 2005

AbstractA fluorescence high performance liquid chromatographic method using an immobilized 3α‐hydroxysteroid dehydrogenase column as a post‐column enzymatic reactor was developed for the determination of corticosteroid metabolites in the urine of subjects with congenital adrenal hyperplasia. 3α‐Hydroxysteroids, such as pregnanetriol, pregnanediol and pregnanetriolone, in the eluate from μ‐Bondapak phenyl column (300 × 3.9 mm I.D.) using 0.05% ammonium phosphate buffer (pH 7.1)–acetonitrile–methanol (100: 55: 15) as the mobile phase was mixed with NAD+ solution in the enzyme column at 30 °C to generate NADH, which was monitored by a fluorophotometric detector. Each steroid was measured at the 2.5 μg/dl at the highest sensitivity of the detector. The mean recoveries and reproducibilities were 91.5–108.2% with 0.9–6.5% (CV%).
Early identification of isovaleric aciduria using photodiode array detection for liquid chromatographic profiling of urinary carboxylic acids
Authors: Buchanan D. N. , Thoene J. G. 
Published: May 2005

AbstractThe 190 nm high performance liquid chromatographic photodiode array profiling of the urinary carboxylic acids of the first urine of a newborn affected with isovaleric aciduria afforded an abnormal peak at 27.8 min. This peak was greatly increased in the carboxylic acid profiling of the 14 h urine sample from the same infant. Isolation of this peak by fraction collecting; solvent extraction of the eluent; trimethylsilyl derivatization of the residue and gas chromatographic/mass spectrometric analysis identified the compound as isovalerylglycine. Correlation of the 190 nm absorbance of isovalerylglycine (y) with concentration (x) afforded a least squares curve: y = 476.4x – 13.72 (r = 0.99) run‐to‐run variation 6.92%; day‐to‐day variation 8.88%; with a minimum detectable concentration of 25 μg/ml.
Combined use of lectin affinity chromatography and endo‐β‐galactosidase to study polylactosamine sequences isolated from haemopoietic cell surfaces
Authors: Morris Andrew J. , Gallagher John T. , Dexter T. Michael 
Published: May 2005

AbstractThe trypsin‐sensitive glycopeptides from cell surfaces of a multipotential murine haemopoietic cell line (DE) have been studied using serial lectin affinity chromatography on columns of immobilized lentil lectin (LCA), concanavalin A (Con A), and wheat‐germ agglutinin (WGA). WGA‐binding material consisted of glycopeptides that failed to bind to LCA and Con A. Step elution from the WGA‐column with 0.01‐, 0.1‐, 0.5‐ and 1.0 M N‐acetyl‐D‐glucosamine yielded four affinity classes of glycopeptide (WGA‐W, WGA‐I, WGA‐S and WGA‐SS respectively). WGA‐W, WGA‐I and WGA‐S contained both alkali‐stable (N‐linked) and alkali‐labile (O‐linked) carbohydrate on high molecular weight glycopeptides. The WGA‐SS fraction contained only N‐linked carbohydrate. N‐linked glycopeptides isolated from each WGA‐binding class differed in molecular size, relative N‐acetylneuraminic acid content and affinity for Ricinus communis 120 agglutinin. endo‐β‐Galactosidase digestion showed that these glycopeptides contained polylactosamine‐type glycans. Gel filtration profiles of the enzyme treated materials were different for each WGA‐binding population suggesting variation in branching patterns and/or substitution with fucose residues. Affinity chromatography has shown that the WGA binding molecules are the major glycopeptide group at DE cell surfaces.
A simple quantitative HPLC assay for ifosfamide in biological fluids
Authors: Margison Jennifer M. , Wilkinson P. M. , Cerny T. , Thatcher N. 
Published: May 2005

AbstractA high performance liquid chromatography method is described for measuring Ifosfamide (I) in human serum. This involves solvent extraction, reverse phase HPLC and UV detection at 190 nm. Standard curves of peak height × detector sensitivity versus I concentration in serum were linear with a lower limit of detection of 100 ng/ml. Authentic 14C‐labelled I cochromatographed with standard I and with I found in serum from treated patients. The concentration‐time curves of I determined by both HPLC and gas chromatography were indistinguishable. We conclude that this method is suitable for determining I pharmacokinetics in biological specimens.
Biosynthesis of bloodgroup I and i antigens. A sensitive and specific assay of UDP‐GlcNAc:β‐galactoside β1 → 3‐N‐acetylglucosaminyltransferase activity in hematopoietic cells by HPLC
Authors: Koenderman Anky H. L. , Loppen Piet L. , Marinus Lian A. M. , van den Eijnden Dirk H. 
Published: May 2005

AbstractA sensitive HPLC method for the assay of UDP‐GlcNAc:β‐galactoside β1 → 3‐N‐acetylglucosaminyltransferase activity was developed. Using lactose as an acceptor, the formation of the product GlcNAcβ1 → 3Galβ1 → 4Glc can be determined without interference by substrates resulting from enzymatic and chemical breakdown of the donor substrate UDP‐GlcNAc. The method is very specific since products of other transferase reactions, which potentially may be formed in the incubations in vitro, elute at positions different from that of GlcNAcβ1 → 3Galβ1 → 4Glc.By use of this assay method it could be demonstrated that normal and malignant hematopoietic cells and cell‐lines, with the exception of erythrocytes and reticulocytes, contain β1 → 3‐N‐acetylglucosaminyltransferase activity.
Measurement of penbutolol and 4‐hydroxypenbutolol in plasma or serum by HPLC
Authors: Bhamra R. K. , Flanagan R. J. , Holt D. W. 
Published: May 2005

AbstractA simple HPLC method for penbutolol and 4‐hydroxypenbutolol assay has been developed. Plasma or serum (200 μl) is vortex‐mixed (30 s) with Tris solution (2 M, pH 10.6) containing an internal standard (50 μl) and methyl t‐butyl ether (200 μl). After centrifugation, the extract (100 μl) is analysed using an unmodified silica column (250 × 5 mm ID) and iso‐octane–methanol–methyl t‐butyl ether (55:25:20) containing ammonium perchlorate (10 mM, pH 5.7) as eluent and with fluorescence detection. No interference has been encountered and the limit of accurate measurement for both compounds is 5 μg/l.
A simple method for the purification of dipeptidyl aminopeptidase IV from porcine kidney using HPLC
Authors: Hutchinson D. W. , Woolfitt A. R. 
Published: May 2005

AbstractDepeptidyl aminopeptidase IV (E.C. 3.4.14.5) has been purified to homogeneity using “soft‐column” chromatography on Sephadex G‐200, DEAE‐cellulose, gly‐pro‐AH‐Sepharose and finally HPLC on TSK G‐3000SW. The purification by HPLC is fast and gives a better yield of pure enzyme than procedures which have been described previously. The enzyme obtained in this manner has a high specific activity (86 U/mg using a saturating level of gly‐pro‐4‐nitroanilide as substrate) and was free of contaminating peptidase activities. Our preparation of DAP IV is suitable for peptide sequencing studies by fast atom bombardment mass spectrometry.
Solid phase extraction and isocratic separation of urinary porphyrins by HPLC
Authors: Kotal Petr , Jirsa Milan , Martásek Pavel , Kordač Václav 
Published: May 2005

AbstractA method for determining urine porphyrins by HPLC is described. In the preliminary step, porphyrins are purified in high yields and concentrated by low pressure reverse‐phase chromatography on C18 (octadecylsilane bonded silica) cartridge. Porphyrins are stable for 10 days after adsorption on C18 cartridge. The separation of porphyrin esters is performed on an aminopropyl‐bonded silica column with an eluting system containing n‐heptane and ethyl acetate. The system enables rapid isocratic separation of porphyrin methyl esters with high selectivity. The simplicity and reproducibility of the whole procedure allows its application to the routine analysis of urinary porphyrins in the clinical laboratory.
Red cell zinc protoporphyrin and protoporphyrin by HPLC with fluorescence detection
Authors: Rossi E. , Garcia‐Webb P. 
Published: May 2005

AbstractA high performance liquid chromatographic (HPLC) method was developed for the determination of zinc protoporphyrin (ZnPP) and protoporphyrin (PP) in whole blood. After adding the blood to dilute acetic acid, ZnPP and PP were extracted with dimethyl sulfoxide–acetone containing mesoporphyrin as internal standard. Following evaporation of the acetone, the haemin‐free extract was analysed by HPLC. ZnPP and PP were separated on a reversed‐phase column and quantitated by measuring fluorescence peak areas. The extraction method is simple, and applicable to batch analysis, and the HPLC separation is rapid and repoducible. The coefficient of variation for ZnPP was 5.6% and 3.3% for total red cell porphyrin levels of 3.5 and 10.2 μmol per litre RBC respectively. Results are discussed in patients with erythrohepatic protoporphyria, lead exposure, iron‐deficiency and non‐specifically elevated total red cell porphyrins.
HPLC determination of orthophosphate coexisting with large amounts of organophosphates in biological samples
Authors: Koshiishi Ichiro , Imanari Toshio 
Published: May 2005

AbstractA simple and accurate HPLC method for the determination of Orthophosphate in the presence of large amounts of organophosphates is described. The method is based on the formation and separation of the molybdenum Orthophosphate complex. In order to prevent the hydrolysis of organophosphates, the sample was deproteinized with silicotungstate in acetate buffer (pH 4.0) under ice‐cooling and then treated with ammonium molybdate in maleate buffer (pH 7.0). The sample was injected onto Styragel 60 Å column (5 mm ID × 100 mm) with 38% (v/v) acetonitrile containing 0.3 M sulfuric acid as eluent. Detection was at 310 nm. The method was applied to the determination of Orthophosphate in liver, kidney, spleen and mouse blood.
Determination of free and total catecholamines in human urine by HPLC with fluorescence detection
Authors: Nohta Hitoshi , Mitsui Akane , Umegae Yoshihiko , Ohkura Yosuke 
Published: May 2005

AbstractA simple and highly sensitive method for the determination of free and total (free + conjugated) catecholamines (norepinephrine, epinephrine and dopamine) in human urine is described which employs HPLC with fluorescence detection. Conjugated catecholamines (sulfate form) are hydrolyzed by a sulfatase‐mediated reaction to the corresponding free amines. After cation exchange chromatography on a Toyopak IC‐SPS cartridge, catecholamines and isoproterenol (internal standard) in urine samples were converted into the corresponding fluorescent compounds by reaction with 1, 2‐diphenylethylenediamine. These compounds were separated within 8 min on a reversed phase column with isocratic elution using a mixture of water, methanol and acetonitrile containing a Tris‐hydrochloric acid buffer (pH 7.0). The detection limit for each catecholamine is ca 2 fmol per 100 μL injection volume.
Analysis of p‐aminobenzoic acid and its metabolites in urine and plasma by ion pair HPLC in the NBT‐PABA pancreatic function test
Authors: Hung C. T. , Perrier D. G. , Schicker A. M. , Zoest A. R. 
Published: May 2005

AbstractAn ion pair HPLC method which can simultaneously detect the major metabolites of an exocrine pancreatic function testing agent (NBT‐PABA) in plasma and urine has been developed. This assay has been applied to a pharmacokinetic study of PABA and its metabolites in 3 healthy adult volunteers following the oral administration of 1 g NBT‐PABA. The 6 h testing period currently used to collect urine following the NBT‐PABA ingestion is adequate for the recovery of PABA and its metabolites. Plasma determination of these compounds may provide an improved evaluation of the pancreatic performance in patients with abnormal liver or kidney function.
Simultaneous determination of gastrodin and its metabolite by HPLC
Authors: Liu Ke‐Xin , Han Guo‐Zhu , Chang Ya‐Lun , Su Cheng‐Ye , Tang Nan‐Yuan , Chen Yu‐Ren 
Published: May 2005

AbstractA rapid and specific HPLC method for the simultaneous determination of gastrodin and its metabolite gastrodigenin (p‐hydroxybenzyl alcohol) in rat plasma, bile, liver, urine and faeces is described. The separation was achieved by using a reversed phase column (YWG‐C18) eluted with methanol‐water (2.5:97.5 v/v). Phloroglucinolum was used as internal standard and the peaks were detected at UV 221 nm. The protein precipitation with ethanol was a very simple and rapid method for sample preparation. The gastrodin and gastrodigenin were quantitated by measuring the peak‐height ratios. There was a linear concentration range of 10–320 μg/mL in the assay for both compounds. The coefficients of variation (within‐day) for samples spiked with gastrodin and gastrodigenin were 2.94% and 3.08%, respectively. The method demonstrated a high specificity and was suitable for use in pharmacokinetic studies.
Rapid purification of arrowhead proteinase inhibitors by high performance hydrophobic interaction chromatography on a PEG bonded phase column
Authors: Chang Jen‐Ping , Yuan Yun 
Published: May 2005

AbstractA new hydrophobic interaction HPLC column is used for the rapid purification of proteinase inhibitors isolated from arrowhead. The inhibitors, partially purified by DEAE‐cellulose column chromatography, are resolved into three components with a mobile phase gradient of decreasing salt concentration from 1.1 M ammonium sulfate in 0.01 M phosphate buffer to phosphate buffer alone. This new HPLC column is found to be very useful for rapid, semipreparative purification of hydrophobic protein and sample loading of up to 1.6 mg of inhibitors can be fully resolved on an analytical column.
HPLC measurement of penticainide and desalkylpenticainide in biological fluids
Authors: Walker S. , Flanagan R. J. , Holt D. W. 
Published: May 2005

AbstractA simple HPLC method has been developed to measure the antiarrhythmic agent penticainide and its N‐desalkyl metabolite in biological fluids. Solvent extraction of a small (200 μL) sample volume with direct analysis of the extract is used to measure the plasma and urinary concentrations of these compounds attained during chronic therapy, although a larger sample volume (1.0 mL) and prior concentration of the extract are required for single oral dose work. In each case chromatographic analysis is performed using a microparticulate (5 μm) silica column and methanolic ammonium perchlorate (10 mM, pH 6.7) as eluent with UV detection (260 nm). No endogenous sources of interference have been encountered and potential interference from other drugs is minimal.
Determination of adriamycin and its fluorescent metabolites in human plasma by HPLC
Authors: Mahdadi R. , Lhermitte M. , Lafitte J. J. 
Published: May 2005

AbstractWe describe a method for measuring adriamycin and its metabolites, adriamycinol and adriamycinone in plasma, using reversed phase HPLC and fluorescence detection. The lower limit of detection is approximately 1 ng/mL for each compound. An extraction technique for serum is described which is capable of an almost equal recovery (>93%) of adriamycin and metabolites without interference from endogenous components of plasma and from other common drugs. Within‐day and day to day coefficients of variation are estimated.
The use of bond‐elut for the estimation of serum bile pigments bonded covalently to albumin
Authors: McKavanagh S. M. , Billing B. H. 
Published: May 2005

AbstractA simple and precise method has been devised for the quantitation of biliprotein (δ‐bilirubin or albumin bound bilirubin) in serum. In the presence of caffeine/benzoate, Bond‐Elut (C8, 200 mg) extracts unconjugated and conjugated bilirubin but not pigments that are covalently bonded to albumin which pass through the column and can be quantitated by a standard diazo method. Following elution from the Bond‐Elut column with methanol‐acetonitrile (50: 50, v/v) unconjugated and conjugated bilirubin can be quantitated either as total pigments or individually by HPLC.
Identification of isoprenoid‐type components in human expired air: A possible shunt pathway in sterol metabolism
Authors: O'Neill Hugh J. , Gordon Sydney M. , Krotoszynski Boguslaw , Kavin Hymie , Szidon Jan P. 
Published: May 2005

AbstractExpired air samples have been analyzed from three groups of human subjects (normal, liver dysfunction, lung cancer) and the baboon (Papio anubus). Of the several hundred compounds present, three compounds were of particular interest due to their structural relationship to the isoprenoid‐type intermediates in the sterol pathway. These compounds were 1‐methyl‐4‐(1‐methyl‐ethenyl)‐cyclohexene, 6‐methyl‐5‐hepten‐2‐one, and 6,10‐dimethyl‐5,9‐undecadien‐2‐one. Hydroxyacetone was also found in all samples screened. The relationship of these compounds to the non‐sterol pathway of mevalonate metabolism is discussed.
Evaluation of vaginal malodor and efficacy of treatment by high performance ion exchange chromatography
Authors: Stanek Ronald , Glover D. D. , Mya Sandra , Larsen Bryan 
Published: May 2005

AbstractHigh performance ion exchange chromatography was employed to evaluate the presence of short chain organic acids in the vaginal fluid of a woman troubled by persistent foul vaginal odor, but who did not have typical bacterial vaginosis. The vaginal secretions from this patient were collected on a weighed cotton swab and eluted into water and extracted by acidified ether. Salts of the acids were back‐extracted into aqueous solution and chromatographed on an H‐form resin column and compared to commercially available standards. A strikingly large amount of caproic acid was found. The caproic acid disappeared after metronidazole therapy, and a subsequent follow‐up chromatogram showed a predominance of lactic acid. The success of this technique in evaluating the present case suggests that such a method may prove useful in other types of vaginal infection.
Computerized chromatographic peak detection using the trigg tracking signal. An application devised for use with an online analog to digital converter connected between an amino acid analyser and a personal computer
Authors: Hartley T. F. , Philcox J. C. , Beesley J. F. , Robson J. B. 
Published: May 2005

AbstractManual integration of the amino acid peaks from physiological samples produced by conventional anion exchange liquid chromatography is a time‐consuming process. This paper describes a combined unit, consisting of an analog to digital converter and a personal computer, which was connected in parallel with the chart recorder and the analyser's 570 nm channel of the colorimeter. The computer was programmed to log the digitized data, detect the start, maximum and end of each chromatographic peak, calculate the area under the peak and its retention time and provide a printoct of the results at the end of the elution program. The computer program successfully exploited the Trigg Tracking Signal as both a peak detection and as a moving baseline monitoring device. This approach proved to have an equivalent performance to the manual method for 17 out of the 19 amino acids normally quantitated in physiological samples. The automated detection and quantitation of arginine was unsatisfactory due to its characteristically low profile peak shape, and proline was not measured because the device was not connected to the 440 nm channel of the colorimeter. The automated system provided economic and analytically acceptable solutions to the problem of providing an online integrator versatile enough to be used with the 255 min long amino acid analysis of physiological fluids.