bluuebunny/crossref_metadata_2025_split huggingface dataset:
Direct diagnosis of tuberculosis by computer assisted pattern recognition gas chromatographic analysis of sputum
Authors: Maliwan Nitaya , Reid Ralston W. , Pliska Stanley R. , Bird Thomas J. , Zvetina James R. 
Published: May 2005

AbstractChemical detection of tuberculosis (TB) products in sputum was attempted by using gas chromatographic analysis in conjunction with different pattern recognition computer models. For the chromatographic separations, we used a 2 mm × 1.8 m packed column and a 0.25 mm × 30 m fused silica capillary column to analyse the methylated glycosides and fatty acid methyl ester derivatives. Three computer pattern recognition methods were applied: error score, TB score and discriminant analysis. These methods predicted the presence of active TB most often in sputa of active TB patients and less so in those from inactive, suspected and non‐TB patients, in that order. Although the best true positive of 75% was obtained from the TB score method and best true negative of 98% from discriminant analysis, the accompanying false positive and false negative results (36% and 50%, respectively) were unacceptable. The use of capillary column or fatty acid methyl ester derivatives of the samples did not improve on the predictive values of chromatograms obtained from the packed column on trimethylsilylglycosidic derivatives. Additional work is needed before this method can have a direct clinical application.
Determination of Nifedipine in plasma by a rapid capillary gas chromatographic method
Authors: Guellec C. Le , Bun H. , Giocanti M. , Durand A. 
Published: May 2005

AbstractA rapid, specific and reliable gas chromatographic assay procedure for Nifedipine in plasma has been developed. With a single‐step solvent extraction, and electron capture detection, the method is sensitive to 0.5 ng/mL of plasma and the standard curve is linear from 0.5 to 500 ng/mL. Samples are protected from light to prevent formation of photodecomposition products. The method has been used to monitor drug concentrations in patients receiving therapeutic doses.
High performance liquid chromatographic determination of 1,5‐anhydroglucitol in human plasma for diagnosis of diabetes mellitus
Authors: Tanaka Shigeo , Nakamori Kota , Akanuma Hiroshi , Yabuuchi Masahiko 
Published: May 2005

AbstractThis paper describes a high performance liquid chromatographic (HPLC) method for determining 1,5‐anhydroglucitol in plasma, in which anion exchange chromatography and pulsed amperometric detection are used. Plasma samples deproteinized with trichloroacetic acid are passed through a three‐layer column packed with (1) strongly basic anion (BO form, the upper layer), (2) strongly basic anion (OH− form, the middle layer) and (3) strongly acidic cation (H+ form, the lower layer) exchange resins. 1,5‐Anhydroglucitol is efficiently recovered in the flow‐through fraction and interfering substances are completely removed by the column treatment. The analytical response of the method is linear with concentration to 40 mg/L, and it is possible to detect as little as 0.1 mg 1,5‐anhydroglucitol per litre of plasma. Analytical recovery is between 96 and 103%, and there is good agreement between the results measured by our method and by a gas/liquid chromatographic method (r = 0.998). The method has been successfully used for the determination of very low 1,5‐anhydroglucitol concentrations (< 1 mg/L) in the plasma of diabetic patients.
Analysis of fragrance compounds in blood samples of mice by gas chromatography, mass spectrometry, GC/FTIR and GC/AES after inhalation of sandalwood oil
Authors: Jirovetz Leopold , Buchbauer Gerhard , Jäger Walter , Woidich Alexander , Nikiforov Alexej 
Published: May 2005

AbstractAfter inhalation experiments with sandalwood oil and the pure fragrance compounds coumarin and α‐terpineol, substances were detected and measured in the blood samples of test animals (mice) using gas chromatography/mass spectrometry (GC/MS) (MID) in connection with GC/FTIR (SWC), GC/AES (carbon and oxygen trace) and flame ionization detection/gas chromatography. Using tiglinic acid benzyl ester as the internal standard the following concentrations in serum could be found: α‐santalol 6.1 ng/mL, β‐santalol 5.3 ng/mL and α‐santalene 0.5 ng/mL. In separate inhalation experiments with coumarin and with α‐terpineol the corresponding concentrations were 7.7 ng/mL and 6.9 ng/mL, respectively.
Determination of intraperitoneal mitoxantrone in the serum of cancer patients using a high performance liquid chromatograph coupled to an advanced automated sample processor (AASP)®
Authors: Micelli G. , Lozupone A. , Quaranta M. , Donadeo A. , Coviello M. , Lorusso V. 
Published: May 2005

AbstractA study has been carried out on 10 patients with ovarian cancer treated by intraperitoneal mitoxantrone. The serum concentration was determined by high performance liquid chromatography with spectrophotometric detection. The extracted analyte on the cartridge was injected and eluted on‐line into the analytical column by the mobile phase. This improved the signal and sample processing rate, without significant loss in analytical performance. Excellent linearity (r >0.9994) was observed for the calibration curve over the range 1–2000 ng/mL, along with a precision within‐day and between‐day estimated as 1.5% and 5.6%, respectively. Sensitivity was an order of magnitude higher than that of the comparison method. From a clinical point of view, these preliminary results have shown that intraperitoneal administration is more beneficial than intravenous therapy. Low serum levels (1–30 ng/mL) with a maximum at the first or second hour are revealed.
High performance ion exclusion chromatographic characterization of the vaginal organic acids in women with bacterial vaginosis
Authors: Stanek Ronald , Glover Douglas D. , Larsen Bryan , Gain Ronald E. 
Published: May 2005

AbstractVaginal organic acids have previously been detected by gas–liquid chromatography, but we have applied an ion exclusion high performance liquid chromatographic procedure to the analysis of vaginal discharge samples. This procedure has the advantage of not requiring derivitization of non‐volatile acids and provides the convenience of a technique which does not require the use of flammable gasses, while allowing the identification of at least 18 different acids from the same chromatographic analysis. Vaginal discharge from women with symptoms of bacterial vaginosis was collected on weighed swabs and analysed for the presence of organic acids. The results were compared to the organic acid content of samples obtained from the same cohort of women after treatment with metronidazole. In addition, samples were obtained from asymptomatic women and these samples were analysed in the same manner. The number of organic acids present in samples from women with bacterial vaginosis was greater than the number found after treatment or among asymptomatic women. Succinic acid appeared to be inversely related to lactate concentration and succinate:lactate ratios were greater among women with bacterial vaginosis before treatment than after treatment. Liquid chromatography has proven useful as a means of evaluating the metabolic end‐products of vaginal microorganisms in situ.
Measurement of recombinant interferon levels by high performance immunoaffinity chromatography in body fluids of cancer patients on interferon therapy
Authors: Phillips Terry M. 
Published: May 2005

AbstractThe technique of high performance immunoaffinity chromatography was used to measure the levels of recombinant interferon in chronic lymphocytic leukaemia patients enrolled in a phase II recombinant interferon clinical trial. The technique employed a short high pressure chromatography column packed with minute glass beads which had monoclonal antibody, directed against recombinant alpha interferon, immobilized to their surface. This system was used to measure interferon levels in a variety of different human body fluids. A good correlation was found when interferon levels, detected by chromatographic separation, were compared to levels obtained by a conventional radioimmunoassay.
Hydrophobic interaction chromatography of fibroblast proteoglycans
Authors: Schmidtchen Artur , Fransson Lars‐Åke 
Published: May 2005

AbstractWe have investigated the hydrophobic properties of human skin fibroblast proteoglycans and related material by affinity chromatography on Octyl‐Sepharose CL‐4B in 4 M guanidinium hydrochloride (GdnHCI). Proteoglycans and related material could be separated into non‐, medium and highly hydrophobic forms by elution with gradients of Triton X‐100 in 4 M Gdn HCI. The non‐hydrophobic material included endogenously produced glycosaminoglycan chains and oligosaccharides as well as an HS‐proteoglycan with a 35 kDa core. The 65–70 kDa core (glypican‐related) proteoglycans appeared among the highly hydrophobic ones, but variable proportions were seen both in the medium and the non‐hydrophobic material. Other membrane‐bound proteoglycans, like fibroglycan (45 kDa core) and the HS‐proteoglycans with 90 and 130 kDa cores, as well as the CS/DS‐proteoglycan with a 90 kDa core, were all of high hydrophobicity. There were also indications of a highly hydrophobic CS/DS‐proteoglycan with a 45 kDa core. The extracellular proteoglycans, PG‐L, PG‐S1 and PG‐S2, and the HS‐proteoglycans with 350 and 250 kDa cores were all of medium hydrophobicity. These proteoglycans emerged in distinct positions when the column was eluted with a gradient of 3‐[(3‐cholamidopropyl)dimethylammonio]propanesulphonate.
Determination of felodipine enantiomers using chiral stationary phase liquid chromatography and gas chromatography/mass spectrometry, and the study of their pharmacokinetic profiles in human and dog
Authors: Sakamoto Takashi , Ohtake Yumi , Itoh Motofumi , Tabata Shigeru , Kuriki Takeo , Uno Kazuo 
Published: May 2005

AbstractA stereoselective and sensitive method for the determination of the enantiomers of felodipine, a dihydropyridine calcium antagonist, has been developed and the pharmacokinetic profiles of the enantiomers comparatively studied after oral administration to dogs and humans. D6‐Felodipine, the internal standard, was added to the plasma, extracted with a solvent and then optically resolved into S(‐) and R(+) enantiomers on a high performance liquid chromatographic Chiralcel OJ column. Each enantiomer in the effluent was analysed by capillary column gas chromatography/positive ion electron impact mass spectrometry. After oral administration of the felodipine racemate, the Tmax and t1/2 values hardly differed between the two enantiomers in dogs and humans. The Cmax and AUC0–24h values of the S(‐) enantiomer were slightly higher than those of the R(+) enantiomer in humans but the difference between the enantiomers was not significant. These results suggested that there is no large difference in the absorption, distribution and elimination of felodipine enantiomers after oral administration of the racemate in either dog or human.
Liquid chromatographic evaluation of purine production in the donor human heart during transplantation
Authors: Smolenski Ryszard T. , Yacoub Magdi H. 
Published: May 2005

AbstractA reversed phase high performance liquid chromatographic technique is presented allowing purine catabolite determination in a whole blood extract without a prior purification step. The method was applied to determine the timing and the profile of myocardial nucleotide catabolite release during reperfusion of the transplanted human heart. Samples of arterial and coronary sinus blood collected at various times within 1 h after aortic declamping during heart or heart‐lung transplantations were used for nucleotide catabolite determination. Massive release of inosine and hypoxanthine from the heart was demonstrated. Production of adenosine was also shown but there was no liberation of xanthine or uric acid. Nucleotide catabolite release was greatest in the first 5 min (coronary sinus‐arterial difference = 15–20 μM), but was still significant after 30 min of reperfusion. The determination of inosine and hypoxanthine–‐major catabolites released–‐was found to be reproducible in coronary sinus blood (coefficient of variation < 10%). However, immediate protein precipitation afer blood sample collection was necessary, as rapid metabolism of both exogenous and endogenous adenosine and inosine was demonstrated.
Fluorescence and chemiluminescence detection of oxazole‐labelled amines and thiols
Authors: Toyo'oka Toshimasa , Chokshi Hitesh P. , Givens Richard S. , Carlson Robert G. , Lunte Susan M. , Kuwana Theodore 
Published: May 2005

AbstractFluorescence and chemiluminescence analyses of amino acids and thiols derivatized with 2‐fluoro‐4,5‐diphenyloxazole (DIFOX) and 2‐chloro‐4,5‐bis(p‐N,N‐dimethylaminosulphonylphenyl)oxazole (SAOX‐CI) were investigated. Thirteen diphenyloxazole (DIOX)‐derivatized amino acids were separated within 38 min by a linear gradient elution from 100% A [0.05 M phosphate (pH 7.0):CH3CN (75:25)] to 100% B [0.05 M phosphate (pH 7.0):CH3CN (1:1)] over 30 min and an isocratic elution of 100% B for 30 min. The detection limits (S/N = 2) with fluorescence detection were in the range of 19–64 fmol. Thiols derivatized with SAOX‐CI were separated by an isocratic elution using 0.1 M H3PO4:CH3CN (65:35) and detected fluorimetrically. The detection limits (S/N = 2) of reduced glutathione, N‐acetylcysteine, 2‐mercaptopropionylglycine, cysteine, homocysteine and captopril were 1.2, 1.5, 1.9, 5.7, 6.4 and 7.9 fmol, respectively. Peroxyoxalate chemiluminescence (CL) intensities of sulphonyl‐5‐N,N‐dimethylaminonaphthalene (DNS), SAOX and DIOX derivatives were compared using three different oxalate esters (DFPO, TCPO and TDPO) by flow injection analysis. The relative chemiluminescence intensity (RCL) of SAOX‐proline and DIOX‐proline were 76–80% and 19–25% of DNS‐proline (100%), respectively. Other SAOX and DIOX derivatives showed lower CL intensities ( < 12%). Extremely low CL intensities were obtained for the fluorescent tagging reagents (<0.11%) and their hydrolysis products (<0.80%). Secondary amino acids and peptides, derivatized with DIFOX in aqueous media at room temperature for 1 h, were detected using DFPO/H2O2. TCPO/H2O2 and TDPO/H2O2 after separation by high performance liquid chromatography. The detection limits (S/N = 2) of hydroxy‐L‐proline, L‐proline, L‐prolyl‐glycyl‐glycine and L‐prolyl‐L‐leucine with the three oxalate esters were 10–17 fmol, 22–34 fmol, 50–61 fmol and 80–123 fmol, respectively.
A sensitive and rapid HPLC‐ECD method for the simultaneous analysis of norepinephrine, dopamine, serotonin and their primary metabolites in brain tissue
Authors: Alburges Mario E. , Narang Neelam , Wamsley James K. 
Published: May 2005

AbstractThis report details a very sensitive, rapid and accurate ion‐pair HPLC‐ECD method for the analysis of biogenic amines and their metabolites in brain tissue. The method described enables detection of picogram amounts of 3‐methoxy‐4‐hydroxy phenethyleneglycol (MHPG) (37 pg), 3,4‐dihydroxy phenylacetic acid (DOPAC) (18 pg), norepinephrine (NE) (12 pg), epinephrine (E) (6 pg), 5‐hydroxyindoleacetic acid (5‐HIAA) (18 pg), 3,4‐dihydroxyphenylethylamine (DA) (6 pg), 3‐methoxy‐4‐hydroxyphenylacetic acid (HVA) (12 pg) and 5‐hydroxytryptamine (5‐HT) (12 pg). The linearity of the method is from 18.75 ng/mL to 300 ng/mL for MHPG; 9.37 to 150 ng/mL for DOPAC and 5‐HIAA; 6.25 to 100 ng/mL for NE, HVA and 5‐HT; and from 3.12 to 100 ng/mL for E and DA. The reproducibility, expressed as coefficient of variance (CV%) within‐run and between‐run groups, was 2.25% and 19.49% for MHPG; 3.84% and 29.84% for DOPAC; 0.89% and 8.97% for NE; 1.26% and 5.61% for E; 1.07% and 28.77% for 5‐HIAA; 2.65% and 10.65% for DA; 5.97% and 24.38% for HVA; and 4.44% and 9.45% for 5‐HT.
Rapid assay of iopanoic acid in dog plasma using a Hisep column
Authors: Andeejani Ahmed M. I. , Hughes Herbert , Feuchuk Danny M. , Aboul‐Enein Hassan Y. 
Published: May 2005

AbstractA rapid method for the determination of iopanoic acid (IOP) in dog plasma utilizing a Hisep column was developed. A mobile phase of 12% methanol, 88% 0.05 M phosphate buffer pH 3.4 yielded a k′ of 8.5 with no interference from proteins present in plasma. Recoveries of IOP from spiked plasma ranged from 97% to 103% at 270 μmol/L and 1.75 mmol/L respectively. Replication was ±2.8% at 1.75 mmol/L and ±6% at 21 μmol/L. A method utilizing 2,4,6‐triiodobenzoic acid as internal standard was also developed for comparison.
A liquid chromatographic method for the determination of fenoprofen in equine plasma and urine
Authors: Delbeke F. T. , Debackere M. 
Published: May 2005

AbstractA high performance liquid chromatographic method to measure plasma and urine fenoprofen levels in equine biofluids is described. Liquid–liquid extraction with diethylether was used to isolate the drug from plasma and urine. The accuracy and reproducibility of the method were within acceptable limits over the concentration range 0–10 μg/mL and 0–20 μg/mL respectively from plasma and urine. Detection limits were 0.05 μg/mL (2 mL plasma) and 0.2 μg/mL (0.5 mL urine). This procedure was applied to ascertain the pharmacokinetics of a 3 g dose of fenoprofen calcium in a horse.
Simultaneous determination of a mixture of organophosphorus and carbamate pesticides by high performance liquid chromatography
Authors: Thapar Sangita , Bhushan Ravi , Mathur R. P. 
Published: May 2005

AbstractA simple HPLC procedure has been developed for the simultaneous determination of a mixture of standard carbaryl, carbofuran, carbendazim, dimethoate, malathion and methyl parathion from a spiked agricultural soil sample. The pesticide mixture has been extracted using methanol–water. A concave gradient elution with acetonitrile–phosphate buffer for 15 min followed by linear elution for 5 min, using a wavelength of 224 nm for detection, has been found to resolve the mixture efficiently.
High performance liquid chromatographic analysis of polypeptide hormones in transplanted rat islets
Authors: Ohkubo Tatsuo 
Published: May 2005

AbstractThis report describes high performance liquid chromatographic analysis of transplanted pancreatic islets. A reversed phase ODS column made it possible to measure rat insulin I, II, rat C‐peptide I, II and glucagon simultaneously in isolated rat islets without using radioisotopes. Freshly isolated islets contained 118.0 ± 9.7 ng (mean ± SE, n = 6) insulin and 3.01 ± 0.60 ng glucagon per islet. The insulin I/II ratio was 1.22 ± 0.03. Isolated islets were then cultured in vitro or transplanted into mice under the renal capsule. Transplantation induced mild hypoglycemia in the recipients. The graft mean survival time was 7.2 ± 0.4 days (n = 5). Both cultured (n = 7) and transplanted (n = 6) islets showed similar alterations of polypepide hormones on day 4. Insulin decreased to one third and glucagon remained unchanged. The insulin I/II ratio increased twofold. In conclusion, it was suggested that the general fate of isolated islets was caused by ischemia and denervation. Relatively, ischemia may not damage α cells but may damage β cells because α cells are peripherally located. Denervation may release β cells from a resting state under neural tonic inhibition. Mild hypoglycemia and an increased insulin I/II ratio were related to the accelerated insulin synthesis in the isolated islets.
A highly sensitive method to quantify triazolam and its metabolites with liquid chromatography—mass spectrometry
Authors: Senda Naoto , Kohta Kimiyoshi , Takahashi Toshiaki , Shizukuishi Kenichi , Mimura Tadao , Fujita Tomoyuki , Nakayama Mitsuru 
Published: May 2005

AbstractWe established a highly sensitive method to determine triazolam and its major metabolites, α‐hydroxytriazolam and 4‐hydroxytriazolam, in human plasma and urine with a liquid chromatography‐mass spectrometry system which incorporates an atmospheric chemical ionization interface. A plasma sample and a urine sample after solvent extraction were injected into an ODS column of reversed phase with a mobile phase in a linear solvent gradient of initially 50 mM ammonium acetate (pH 4.0) 50%: methanol 50% and 15 min later methanol 100%; quantification limits of as low as 20 pg/mL at an SNR of 3 were obtained for each compound. With diazepam as an internal standard, recovery yields of 84, 81, and 77% were obtained for triazolam, α‐hydroxytriazolam and 4‐hydroxytriazolam, respectively.
Determination of chondroitin sulphates in human whole blood, plasma and blood cells by high‐performance liquid chromatography
Authors: Huang Yong , Toyoda Hidenao , Toida Toshihiko , Imanari Toshio 
Published: May 2005

AbstractA simple HPLC method for determination of chondroitin sulphates as thier unsaturated disaccharides by chondroitinases has been applied to measure the glycosaminoglycans (GAGs) in human whole blood, plasma and blood cells. This method may be useful for the investigations on the role of blood GAGs and the metabolic fates of the exogenous GAG.
Quantitative determination of 25‐hydroxyvitamin D3 3‐sulphate in human plasma using high performance liquid chromatography
Authors: Shimada Kazutake , Mitamura Kuniko , Kitama Nami 
Published: May 2005

AbstractThe quantitative determination of 25‐hydroxyvitamin D3 3‐sulphate in human plasma was completed using reversed phase high performace liquid chromatography with UV detection (265 nm) and an internal standard method. The vitamin D sulphate fraction was obtained from a plasma specimen with the combined use of a Bond Elut C18 cartridge for solid‐phase extraction and a piperidinohydroxypropyl Sephadex LH‐20 column for lipophilic ion‐exchange chromatography. Separation of the compounds was performed on a YMC‐Pack ODS‐AM column. The limit of quantitation was 5 ng/mL and the assay was linear from 5 to 50 ng/mL. The proposed method is satisfactory in its accuracy and precision.
Chiral separation of naphthalene‐2, 3‐dialdehyde labelled peptides by cyclodextrin‐modified electrokinetic chromatography
Authors: DeSilva Kapila , Jiang Qun , Kuwana Theodore 
Published: May 2005

AbstractThe chiral separation of several dipeptide enantiomers, derivatized by naphthalene‐2,3‐dialdehyde (NDA), was achieved by use of cyclodextrin‐modified micellar electrokinetic chromatography (CD‐MEKC). The dipeptides contained one or two chiral centers. In the case of several dipeptides containing two chiral centers, all four of the optical isomers could be separated and baseline resolved in less than 15 min with 20 mM γ‐CD and 50 mM sodium dodecyl sulphate (SDS) in the background electrolyte. The order of elution of these derivatized dipeptides was explained by considering important chemical equlibria in the SDS, CD and peptide system. Additionally, the influence of geometric location of the chiral center, the structure of the side‐chain and the effect of CD concentration on the resolution are discussed.
Behaviour of tyrosine amino transferase and convertase during the first hours after hepatectomy in rats
Authors: Biondi Roberto , Viola‐Magni Maria Pia 
Published: May 2005

AbstractThe activity of rat liver tyrosine amino transferase (TAT) increases after hepatectomy with a first prominent peak at 8 h and a second peak at 18 h. This change in activity is probably due to de novo enzyme synthesis since it is prevented by actinomycin‐D (AMD). In the same period an increase of the lysosomal converting enzyme (convertase) which catalyses the in vitro transition of TAT from form I to form III, has been observed; this is not accompanied by changes of other lysosomal enzymes, such as acid phosphatase and cathepsin L. The activity of convertase is equal to that of the controls (sham operated animals) 2 h after hepatectomy, increases three times at 5 h, maintains the same value at 8 h and then decreases slowly to control level after 24 h. The correlation between the activity changes of the two enzymes strongly suggests a physiological role of convertase in TAT turnover.