bluuebunny/crossref_metadata_2025_split huggingface dataset:
Putting the colours into chromogenic in situ hybridization (CISH)
Authors: Shipley J 
Published: July 2006

AbstractRecurrent genomic alterations are the hallmarks of particular cancers. Application of molecular cytogenetic technologies to tumour material in order to detect these alterations has become important for molecular diagnostics and research. A dual‐colour chromogenic in situ hybridization (dc‐CISH) method described recently in the Journal of Pathology has the advantage of visualizing two probes simultaneously with the ability to discern morphological features. In addition, the bright field microscopy required is readily accessible to many laboratories. The approach has been validated by comparison of results with standard analyses for HER‐2 amplification status in formalin‐fixed, paraffin‐embedded breast cancers and is applicable to the analysis of other clinically relevant genomic aberrations as well as of use in research investigations. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Redox chemistry of 8‐azaadenine: a pulse radiolysis study
Authors: Pramod G. , Mohan H. , Manoj P. , Manojkumar T. K. , Manoj V. M. , Mittal J. P. , Aravindakumar C. T. 
Published: July 2006

AbstractAza derivatives of purines and pyrimidines are important class of compounds, which are known for their cytotoxic, antimicrobial, and mutagenic activities. The redox chemistry of 8‐azaadenine (8AA) has been investigated using pulse radiolysis technique. The oxidation reactions were studied using hydroxyl radical (.OH), oxide radical anion (O.− and sulfate radical anion (SO), and the reduction reactions were studied using hydrated electron (e) and hydrogen radical (H.). In the reaction of .OH, a bimolecular rate constant of 3.8 × 108 dm3 mol−1 s−1 was determined at pH 6.0. The transient spectrum obtained for the reaction of .OH at pH 6 has an absorption maximum around 340 nm and is assigned to the formation of 8AA‐4OH.. The charge population density was calculated theoretically (using Gaussian 98) and it showed that the fourth carbon atom (C(4)) is the most probable site for the attack of .OH. The oxidizing nature of this radical is demonstrated by its reaction with N,N,N′,N′‐tetramethyl‐p‐phenylenediamine (TMPD). The existence of this species is further supported by theoretical calculations where the absorption maximum of this radical is calculated as 338 nm. The yield of 8AA‐4OH. is estimated as around 85%. At pH 10.2, the transient spectrum with maxima at 300 and 350 nm is attributed to the dehydrated 8AA‐4OH., which is an N‐centered radical of the type 8AA‐N(9).. In the reaction of O.− (pH ≈ 14) a transient spectrum with similar features is observed. Therefore this is also assigned to 8AA‐N(9).. A bimolecular rate constant for this reaction is determined as 4.2 × 108 dm3 mol−1 s−1. In the reaction of SO at pH 6, the transient spectrum having λmax at 320 nm is attributed to the formation of a neutral radical of 8AA (8AA‐N(6).), which is formed by the deprotonation of the initially formed radical cation. But at pH 10.2, the spectrum is found to be similar to the one observed in the reaction of O.− and hence it is assigned to the formation of the nitrogen‐centered radical 8AA‐N(9).. In the reaction of e, a second‐order rate constant of 1.8 × 1010 dm3 mol−1 s−1 is determined at pH 6 and the transient absorption spectrum with λmax at 330 nm is assigned to the protonated electron adduct of 8AA (8AA(NH.)). The reducing nature of this intermediate is confirmed by the formation of methyl viologen radical cation (MV.+) from its reaction with MV2+. The transient intermediate in the case of the reaction of H. is proposed as 8AA‐C2(H)N(3). at pH 1. Copyright © 2006 John Wiley & Sons, Ltd.
Mechanical endurance of polymer electrolyte membrane and PEM fuel cell durability
Authors: Huang Xinyu , Solasi Roham , Zou Yue , Feshler Matthew , Reifsnider Kenneth , Condit David , Burlatsky Sergei , Madden Thomas 
Published: July 2006

AbstractThe life of proton exchange membrane fuel cells (PEMFC) is currently limited by the mechanical endurance of polymer electrolyte membranes and membrane electrode assemblies (MEAs). In this paper, the authors report recent experimental and modeling work toward understanding the mechanisms of delayed mechanical failures of polymer electrolyte membranes and MEAs under relevant PEMFC operating conditions. Mechanical breach of membranes/MEAs in the form of pinholes and tears has been frequently observed after long‐term or accelerated testing of PEMFC cells/stacks. Catastrophic failure of cell/stack due to rapid gas crossover shortly follows the mechanical breach. Ex situ mechanical characterizations were performed on MEAs after being subjected to the accelerated chemical aging and relative humidity (RH) cycling tests. The results showed significant reduction of MEA ductility manifested as drastically reduced strain‐to‐failure of the chemically aged and RH‐cycled MEAs. Postmortem analysis revealed the formation and growth of mechanical defects such as cracks and crazing in the membranes and MEAs. A finite element model was used to estimate stress/strain states of an edge‐constrained MEA under rapid RH variations. Damage metrics for accelerated testing and life prediction of PEMFCs are discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2346–2357, 2006
Bronchial hyperresponsiveness, atopy, and bronchoalveolar lavage eosinophils in persistent middle lobe syndrome
Authors: Priftis Kostas N. , Anthracopoulos Michael B. , Mermiri Despina , Papadopoulou Athina , Xepapadaki Paraskevi , Tsakanika Constantina , Nicolaidou Polyxeni 
Published: July 2006

AbstractMost cases of middle lobe syndrome (MLS) in children are considered to be due to asthma and may recover spontaneously; however, in persistent MLS, repeated episodes of infection often institute a vicious cycle that may lead to persistent symptoms and bronchial hyperresponsiveness (BHR). The present study was undertaken to investigate whether asthma, as an underlying diagnosis, is predictive of a favorable outcome of children with persistent MLS. We evaluated 53 children with MLS who underwent an aggressive management protocol that included fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL). These patients were compared to two other groups: one consisting of children with current asthma but no evidence of MLS (N = 40) and another of non‐asthmatic controls (N = 42), matched for age and sex. Prevalence of sensitization (≥1 aeroallergen) did not differ between patients with MLS and “non‐asthmatics” but was significantly lower than that of “current asthmatics.” A positive response to methacholine bronchial challenge was observed with increased frequency among children with MLS when compared to “current asthmatic” and non‐asthmatic children. Multivariate logistic regression analysis revealed a positive correlation between an increased number of eosinophils in the BAL fluid (BALF) and a favorable outcome, whereas no correlation was detected between sensitization or BHR and BAL cellular components. In conclusion, children with MLS have an increased prevalence of BHR, even when compared to asthmatics, but exhibit prevalence of atopy similar to that of non‐asthmatics. An increased eosinophilic BALF count is predictive of symptomatic but not radiographic improvement of MLS patients after aggressive anti‐asthma management. Pediatr Pulmonol. © 2006 Wiley‐Liss, Inc.
Isolation, structure elucidation and In Vivo hepatoprotective potential of trans‐tetracos‐15‐enoic acid from Indigofera tinctoria Linn.
Authors: Singh B. , Chandan B. K. , Sharma N. , Bhardwaj V. , Satti N. K. , Gupta V. N. , Gupta B. D. , Suri K. A. , Suri O. P. 
Published: July 2006

AbstractThe bioassay guided fractionation of the dried aerial part of Indigofera tinctoria Linn. led to the identification of an active fraction labelled as indigotin. On further chemical analysis, a compound isolated from indigotin was identified and characterized as trans‐tetracos‐15‐enoic acid (TCA). The chemical structure of this compound was established on the basis of physical properties and spectral data, including NMR. It afforded significant hepatoprotection against carbon tetrachloride and paracetamol induced hepatotoxicity in experimental models. Silymarin, a well known plant based hepatoprotective agent, and N‐acetylcysteine, which has proven efficacy as a replenisher of sulfhydryls, were used for relative efficacy. TCA was found to reverse the altered hepatic parameters in experimental liver damage. In the safety evaluation study the oral LD50 was found to be more than 2000 mg/kg, with no signs of abnormalities or any mortality for the 15 day period of observation after administration of a single dose of drug in mice. The studies revealed significant and concentration dependent hepatoprotective potential of TCA as it reversed the majority of the altered hepatic parameters in experimental liver damage in rats and mice and may be useful in the management of liver disorders. Copyright © 2006 John Wiley & Sons, Ltd.
Quantitative determination of rosuvastatin in human plasma by liquid chromatography with electrospray ionization tandem mass spectrometry
Authors: Xu Dong‐Hang , Ruan Zou‐Rong , Zhou Quan , Yuan Hong , Jiang Bo 
Published: July 2006

AbstractA simple and sensitive liquid chromatography/tandem mass spectrometry method was developed and validated for determining rosuvastatin in human plasma, a new synthetic hydroxymethylglutaryl‐coenzyme A reductase inhibitor. The analyte and internal standard (IS; cilostazol) were extracted by simple one‐step liquid/liquid extraction with ether. The organic layer was separated and evaporated under a gentle stream of nitrogen at 40°C. The chromatographic separation was performed on an Atlantis C18 column (2.1 mm × 150 mm, 5.0 µm) with a mobile phase consisting of 0.2% formic acid/methanol (30:70, v/v) at a flow rate of 0.20 mL/min. The analyses were carried out by multiple reaction monitoring (MRM) using the precursor‐to‐product combinations of m/z 482 → 258 and m/z 370 → 288. The areas of peaks from the analyte and the IS were used for quantification of rosuvastatin. The method was validated according to the FDA guidelines on bioanalytical method validation. Validation results indicated that the lower limit of quantification (LLOQ) was 0.2 ng/mL and the assay exhibited a linear range of 0.2–50.0 ng/mL and gave a correlation coefficient (r) of 0.9991 or better. Quality control samples (0.4, 8, 25 and 40 ng/mL) in six replicates from three different runs of analysis demonstrated an intra‐assay precision (RSD) 7.97–15.94%, an inter‐assay precision 3.19–15.27%, and an overall accuracy (relative error) of < 3.7%. The method can be applied to pharmacokinetic or bioequivalence studies of rosuvastatin. Copyright © 2006 John Wiley & Sons, Ltd.
Surface‐activated chemical ionization and high‐flow gradient chromatography to reduce matrix effect
Authors: Cristoni Simone , Bernardi Luigi Rossi , Gerthoux Piermario , Mocarelli Paolo , Brambilla Maura , Gonella Elisabetta , Guidugli Federico , Cantu Marco 
Published: July 2006

AbstractThe new atmospheric pressure chemical ionization source, named surface‐activated chemical ionization (SACI), has been used in conjunction with high‐flow gradient chromatography to reduce the matrix effect. This high‐flow gradient chromatography approach avoids the co‐elution of analyte and biological matrix compounds that leads to a reduction in quantitation errors due to matrix effect. However, this approach cannot be employed with the classical electrospray ionization (ESI) source that usually works at low eluent flow (< 300 µL/min). SACI can work at high eluent flow (100–2000 µL/min) and can be employed in conjunction with high‐flow gradient chromatography. The reduction in matrix effect in tacrolimus analysis in protein‐precipitated blood samples, an important immunosuppressive agent for renal transplantation, is presented and discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Simple, rapid solid‐phase extraction procedure for the determination of ultra‐trace levels of pyrethroids in ground and sea water by liquid chromatography/electrospray ionization mass spectroscopy
Authors: Gil‐García M. D. , Barranco‐Martínez D. , Martínez‐Galera M. , Parrilla‐Vázquez P. 
Published: July 2006

AbstractA method based on liquid chromatography/mass spectroscopy with electrospray ionization in positive mode (LC/ESI‐MS) to determine trace levels of pyrethroids in environmental water samples has been developed. The chromatographic and the MS parameters were optimized to obtain the best sensitivity and selectivity for all pesticides. Solid‐phase extraction (SPE) using C18 cartridges was applied for preconcentration of pesticide trace levels (ng/L) in both ground and sea water samples. The preconcentration step was carried out with 800 mL of water sample modified with 200 mL of MeOH to improve the recovery percentages in the SPE procedure. The SPE‐LC/ESI‐MS methodology was applied to determine pyrethroids in ground and sea water samples spiked at ng/L concentration levels. Recoveries obtained in ground water were satisfactory (between 72 and 110%). However, an enhancement of the signals of all pesticides in the sea water was found due to the negative effect of the salt in the ionization source. To eliminate this effect a simple cleanup step of the SPE cartridge using 200 mL of Milli‐Q water was performed. The cleanup removed the matrix effect completely from the marine samples. Thus, the recovery percentages ranged from 80 to 115%. The method was applied to determine ng/L of pyrethroids in both ground and marine water samples with precision values lower than 10%. Copyright © 2006 John Wiley & Sons, Ltd.
Pyrolysis mass spectrometry for distinguishing potential hoax materials from bioterror agents
Authors: Wilkes Jon G. , Rafii Fatemeh , Sutherland John B. , Rushing Larry G. , Buzatu Dan A. 
Published: July 2006

AbstractPyrolysis mass spectrometry (PyMS) was investigated as a rapid tool to distinguish potential bioterror hoax materials from samples containing pathogenic bacteria. A pyrolysis time‐of‐flight (TOF) mass spectrometer equipped with an alternative ionization technique, metastable atom bombardment (MAB), was used to produce sample spectra. These spectra were analyzed by principal component and discriminant analysis for pattern recognition. Materials investigated were two strains of Vibrio parahaemolyticus, one of which produced the tdh toxin, two Salmonella enterica serotypes, a biological mosquito control product containing spores of Bacillus thuringiensis, and several white to off‐white powders (which could be used as hoax materials), such as flour, corn starch, methyl cellulose, and xanthan gum. PyMS distinguished bacterial samples from hoax materials. Furthermore, pattern analysis differentiated Vibrios from Salmonellae, Salmonella enterica Anatum from S. enterica Heidelberg, and the two V. parahaemolyticus strains from each other. The B. thuringiensis mixture was distinguished from other bacteria and powders, suggesting that PyMS with pattern recognition may differentiate samples containing pathogens, including Bacillus spp., from nonbiological agents and that it can be a rapid method for detection of bacteria. MS data acquisition took only 7 min for each sample. Published in 2006 by John Wiley & Sons, Ltd.
Electrospray ionization tandem mass spectral analysis of oxidation products of precursors of sulfur mustards
Authors: Tak Vijay , Kanaujia Pankaj K. , Pardasani Deepak , Gupta Arvinda K. , Palit Meehir , Srivastava R. K. , Dubey Devendra K. 
Published: July 2006

AbstractElectrospray ionization tandem mass spectral (ESI‐MSn) analysis of thiodiglycol, bis(2‐hydroxyethylthio)alkanes (BHETAs) and their mono‐, di‐, tri‐, and tetraoxygenated compounds was carried out to obtain their characteristic spectra for ESI‐MS analysis. These compounds are important markers of chemical warfare agents, namely sulfur mustards. ESI‐MSn (n ≥ 3) analysis of a compound by collisionally induced dissociation in an ion trap gives rise to mass spectra that are somewhat similar to electron ionization mass spectra. These ESI‐MSn spectra can be used for compound identification. Under ESI‐MS and ESI‐MS/MS the compounds mostly produced [M+NH4]+, [M+H]+ and [M+HH2O]+ ions. Fragmentations of these even‐electron precursors in the ion trap gave rise to characteristic product ions via neutral loss of O2, H2O, C2H4, HCHO, C2H4O, C2H4S, HSC2H4OH and C2H4SO. Fragmentation routes of these compounds are proposed that rationalize the formation of product ions in ESI‐MSn analysis. Copyright © 2006 John Wiley & Sons, Ltd.
Analysis of sterols by high‐performance liquid chromatography/mass spectrometry combined with chemometrics
Authors: Nagy Kornél , Jakab Annamaria , Pollreisz Ferenc , Bongiorno David , Ceraulo Leopoldo , Averna Maurizio R. , Noto Davide , Vékey Károly 
Published: July 2006

AbstractA newly developed high‐performance liquid chromatography/mass spectrometry (HPLC/MS) method has been successfully used to analyze plasma concentrations of various phytosterols (cholestanol and β‐sitosterol) and cholesterol metabolites (desmosterol and lathosterol). This was based on an unusual solvent combination of water/methanol vs. methanol/acetone/n‐hexane applied on a Purospher Star RP‐18e (125 × 2 mm, 3 µm) column, which proved excellent for the separation, identification and quantification of plasma sterols. Simple solid‐phase extraction preparation of plasma samples was performed, followed by the developed fast and robust HPLC separation. Results on four groups of people were compared, those with low, normal and high plasma cholesterol levels and those with high cholesterol levels on statin therapy, and the results were evaluated using linear discriminant analysis (LDA). Variable selection for LDA was achieved using backward removal selection. Highly discriminatory variables were the ratios of desmosterol to sitosterol and of lathosterol to total plasma cholesterol. The latter ratio was also excellent for distinguishing subjects on statin therapy. The success rate of classification was 100%. The present pilot study shows the potential of HPLC/MS analysis and chemometrics for studying cholesterol‐related disorders and warrants future full‐scale medical study. Copyright © 2006 John Wiley & Sons, Ltd.
Systematic examination of the signal area precision of a single quadrupole enhanced low mass option (ELMO) TSQ™ mass spectrometer
Authors: Fischer Klaus , Höffler Susanne , Meyer Axel 
Published: July 2006

AbstractTo examine the precision of the signal area response of an enhanced low mass option (ELMO) MSQ™ mass spectrometer, operated in the negative electrospray ionization (ESI) mode, extended tests were performed, using flow injection analysis mass spectrometry (FIA‐MS). Analytes were nitrate, nitrite, malonic acid, and D,L‐mandelic acid. Composition and concentration of injected samples, application of an ASRS anion suppressor and of the cone wash unit, methanol addition to the FIA flow medium, and the voltage bias of the hexapole transfer lens were test variables. Individual test cycles comprised up to 90 injections, processed within 20 h. With a few exceptions the signal response tended to decline over time leading to a loss of more than 80% of the initial signal area in extreme cases. A hexapole radio‐frequency (RF) voltage bias of −0.3 V led to an overall low detector response and to high losses of sensitivity over time. Other correlations between the insufficient signal reproducibility and FIA‐MS operating conditions could not be established. The test scheme gave hints how to localize the cause of the mass spectrometer malfunction. The repetition of the test scheme after remedying the detected electronic default demonstrated that relative standard deviations less than 5% can be achieved for a sequence of 30 injections if methanol is added to the FIA flow medium and if a suppressor is used. Based on these findings a recommendation is formulated to supplement current test schemes for instrument performance verification by a detector response precision criterion. Copyright © 2006 John Wiley & Sons, Ltd.
The Transduction of Rat Submandibular Glands by an Adenoviral Vector Carrying the Human Growth Hormone Gene is Associated with Limited and Reversible Changes at the Infusion Site
Authors: Elmore S. , Lanning L. , Allison N. , Vallant M. , Nyska A. 
Published: July 2006

Adenoviral vectors have been shown to efficiently deliver exogenous genes to salivary glands and have therefore been investigated as tools for the treatment of human disease. The purpose of this study was to evaluate the response of F344 rats to intraductal infusion of the right submandibular salivary gland with an adenoviral vector encoding the gene for human growth hormone (AdCMVhGH). Co-administration of hydroxychloroquine (HCQ) was used to redirect the secretion of human growth hormone (hGH) from saliva into serum. This paper documents the findings of the pathology evaluation of this National Toxicology Program study. The right submandibular salivary gland (infusion site) was the primary target organ, with microscopic lesions characteristic of a mild to moderate insult observed at 3 days post infusion in vector exposed animals. These lesions were characterized by variable degrees of acute glandular inflammation, degeneration and necrosis, with more severe lesions in the higher dose groups. Rats at 28 days post infusion had milder inflammation, degeneration and necrosis compared to day 3 rats, with variable degrees of regeneration. In conclusion, the effects on the salivary glands are reversible as indicated by the milder inflammation and degeneration in the day 28 rats concomitant with mild to moderate regeneration. Therefore, the vector appears relatively innocuous with limited tissue toxicity. [The supplemental data referenced in this paper is not printed in this issue of Toxicologic Pathology. It is available as a downloadable file in the online edition of Toxicologic Pathology, 34(4). In order to access the full article online, you must have either an individual subscription or a member subscription accessed through www.toxpath.org .]
Methadone: old problems for new programmes
Authors: BURGESS PHILIP M. , GILL ANTHONY J. , PEAD JOHN , HOLMAN C. PAUL 
Published: July 2006

AbstractThe present paper is concerned with factors which compromise the effective delivery of programmes incorporating methadone. Current clinical practices and programme characteristics are reviewed and policy issues regarding the role of methadone are considered, especially within the context of containing the spread of HIV infection. These issues are discussed in relation to empirical outcome studies, local prescribing trends and clinical case material. The authors conclude that there is an urgent need for: (1) an evaluation of the outcome of private practitioner methadone dispensation versus comprehensive agency‐based therapy; (2) the accreditation of staff in all programmes incorporating methadone; and (3) the development of monitoring mechanisms, including on‐site clinical audits of programmes.
Alcohol and drug dependence: syndrome, strong attachment or everyday behaviour?
Authors: STOCKWELL TIM , SAUNDERS BILL 
Published: July 2006

AbstractThe concept of the dependence syndrome has largely replaced that of ‘alcoholism’ and ‘addiction’ in official classifications of alcohol‐ and drug‐related disorders. However, the utility of the concept has been widely disputed by psychologists and other social scientists. The authors of this paper, both clinical psychologists, hold opposing positions on this issue. Following a brief statement of these positions and an outline of the dependence syndrome, the authors debate a range of disputed issues.