bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infant immunization and the occurrence of atopic disease in Dutch and German children: A nested case‐control study
Authors: Mommers M. , Weishoff‐Houben M. , Swaen G.M.H. , Creemers H. , Freund H. , Dott W. , van Schayck C.P. 
Published: July 2004

AbstractOur goal was to assess the role of early childhood vaccination in the occurrence of respiratory symptoms and allergic sensitization in 7–8‐year‐old Dutch and German children. A nested case‐control study was conducted among children participating in a large longitudinal study on respiratory health, to study the relationship between vaccination (bacille Calmette‐Guérin (BCG), pertussis, measles/mumps, rubella, and Haemophilus influenza type b (Hib)) and respiratory symptoms and allergic sensitization. Parents of 510 7–8‐year‐old children with respiratory complaints and an equal number of randomly selected children without respiratory complaints were asked to complete a questionnaire. Blood samples were collected for specific serum IgE analysis. Vaccination status was assessed through the records of the participating Municipal Health Services. No association between vaccination against pertussis, measles, rubella, or Hib and respiratory symptoms or allergic sensitization was found. For sensitization against house dust mite, BCG vaccination resulted in an increased risk (OR, 2.28; 95% CI, 1.05–4.96). Birth order was inversely associated with allergic sensitization, but was not related to respiratory symptoms. We found an association between BCG vaccination and the subsequent risk for sensitization against house dust mite. No evidence was found for an association between vaccination and respiratory symptoms. Earlier reports of an association of birth order with atopic disease were supported by the results of the present study. Pediatr Pulmonol. 2004; 38:329–334. © 2004 Wiley‐Liss, Inc.
Longitudinal pulmonary status of cystic fibrosis children with meconium ileus
Authors: Li Zhanhai , Lai HuiChuan J. , Kosorok Michael R. , Laxova Anita , Rock Michael J. , Splaingard Mark L. , Farrell Philip M. 
Published: July 2004

AbstractAlthough meconium ileus (MI) is the earliest manifestation of cystic fibrosis (CF), and is associated with poorer growth, the longitudinal pulmonary progression of CF children with MI is not clear. To test the hypothesis that MI is associated with worse pulmonary outcomes, we prospectively compared from diagnosis to 12 years of age 32 CF children with MI to 50 CF children without MI who were diagnosed during early infancy through neonatal screening. Pulmonary outcome measures included respiratory symptoms, respiratory infections, pathogens, antibiotic usage, hospitalizations, quantitative chest radiology, spirometry, and lung volume determinations. Obstructive lung disease was defined as percent predicted spirometry values below the lower limits of normal. Longitudinal analyses revealed no significant differences in cough, wheezing, respiratory infections, prevalence of and median times to acquisition of Pseudomonas aeruginosa or Staphylococcus aureus, antibiotic usage, and chest radiograph scores between the two groups. However, MI children showed significantly worse forced expiratory volume in 1 sec (FEV1), forced vital capacity (FVC), forced expiratory flow between 25–75% of FVC (FEF25–75), % predicted FEV1, % predicted FEF25–75, and total lung capacity (TLC). These differences were particularly apparent beginning at age 8–10 years. MI children also had higher rates of and shorter median times to obstructive lung disease. Subgroup analyses showed MI children treated surgically and those treated medically had similar pulmonary outcomes. In conclusion, MI children have worse lung function and more obstructive lung disease than those without MI. Such abnormalities are accompanied by reduced lung volume. MI is a distinct CF phenotype with more severe pulmonary dysfunction. Pediatr Pulmonol. 2004; 38:277–284. © 2004 Wiley‐Liss, Inc.
Treatment with tobramycin solution for inhalation reduces hospitalizations in young CF subjects with mild lung disease
Authors: Murphy Timothy D. , Anbar Ran D. , Lester Lucille A. , Nasr Samya Z. , Nickerson Bruce , VanDevanter Donald R. , Colin Andrew A. 
Published: July 2004

AbstractOur objective was to study the effect of tobramycin solution for inhalation (TSI; TOBI®, Chiron Corp.) on lung function decline rate in 400 young persons with cystic fibrosis (CF) and mild lung disease. Effects on hospitalization, antibiotic use, school days missed, and nutritional status also were determined. This was an open‐label, randomized (stratified by sex and age group, i.e., 6–10 and 11–15 years), parallel‐group, multicenter study. Routine subject management (control group) was compared to routine management plus 28 days of twice‐daily TSI inhalation, followed by 28 days off the drug (TSI group) for 56 weeks. Primary efficacy endpoints included rate of lung function decline (as measured by forced expiratory volume in 1 sec; FEV1), hospitalization, and concomitant antibiotic use. Safety was assessed by analysis of treatment‐emergent adverse events. Only 184 of 400 planned subjects were recruited and randomized (93 to the TSI group, and 91 to the control group). Enrollment was ended after 2 years because of difficult recruitment. An interim safety review showed a 2.42‐fold risk of respiratory hospitalization for control group subjects (P = 0.020), and the study was terminated. Sixty‐three subjects (34.2%) completed the entire study (30 in the TSI group, or 32.3%; and 33 in the control group, or 36.3%). Significantly fewer TSI subjects were hospitalized for worsening of respiratory symptoms (11.0% vs. 25.6%; P = 0.011), and fewer TSI subjects were hospitalized overall (16.5% vs. 27.8%; P = 0.065). Fewer TSI subjects received antibiotics other than the study drug (78.0% vs. 95.6%), and significantly fewer received oral antibiotics (76.9% vs. 91.1%; P = 0.009). No other safety or adverse event differences were observed. In conclusion, significant reductions in respiratory hospitalizations, concomitant antibiotic use, and a trend towards improvement in percent predicted forced expiratory flow (FEF25–75) provide evidence of a clinical benefit of TSI use in young persons with CF and mild lung disease. An effect on lung function decline rate could not be evaluated as planned, due to inadequate enrollment and early study termination. Pediatr Pulmonol. 2004; 38:314–320. © 2004 Wiley‐Liss, Inc.
Pulmonary lymphangiectasia: Diagnosis and clinical course
Authors: Esther Charles R. , Barker Pierre M. 
Published: July 2004

AbstractPulmonary lymphangiectasia (PL) is a rare disease characterized by dilation of the normal lung lymphatics. The disease was previously associated with a poor prognosis. However, several recent case reports and case studies indicate that survival is possible in the severe neonatal form of PL, and the prognosis is good for infants who present after the neonatal period. In this report, we describe the etiology, clinical presentation, diagnosis, management, and outcome of PL. A revised classification of PL is proposed, based on the current state of knowledge of its etiology and presentation. Pediatr Pulmonol. 2004; 38:308–313. © 2004 Wiley‐Liss, Inc.
Measurement of inspiratory flow in children with acute asthma
Authors: Bentur Lea , Mansour Yasser , Hamzani Yaniv , Beck Raphael , Elias Nael , Amirav Israel 
Published: July 2004

AbstractDry‐powder inhalers (DPIs) have been proposed for treatment of acute asthma. Different DPIs vary in their inspiratory resistance and have different recommended optimal peak inspiratory flows (PIFs). Reduced PIF during acute asthma may result in inadequate drug delivery to the lungs. Our aim was to measure the inspiratory flow in relation to inspiratory resistance during acute asthma in children presenting to the emergency room. School‐age (range, 6–18 years) children were referred to the emergency room for acute asthma. PIF measurements were performed by In‐Check Dial™ device with simulated airflow resistances equivalent to Turbuhaler®, Diskus,® and free flow. Percent change in PIF between remission and acute asthma (%Δ) was correlated with percent change in clinical score (CS) and percent change in spirometry in children <9 and >9 years old. Thirty‐three children (21 males) participated. PIF with simulated Turbuhaler resistance was significantly lower than with simulated Diskus resistance in both acute and remission states (P < 0.0001). PIF with simulated Turbuhaler resistance increased from 62.1 ± 15.3 (acute) to 74.4 ± 16.5 l/min (remission, P < 0.0001), while with Diskus it rose from 72.6 ± 20.5 to 91.1 ± 18.9 l/min (P < 0.0001). Turbuhaler %Δ PIF correlated with %Δ FEV1 (P = 0.01) and with %Δ CS (P = 0.0001). A lesser degree of correlation was observed while using Diskus resistance and in children above 9 years old. During acute asthmatic attacks, PIF is reduced; this reduction is particularly prominent in young children who use a high‐resistance device. However, the PIF generated is generally within the values considered compatible with adequate lung deposition with both Diskus and Turbuhaler. Pediatr Pulmonol. 2004; 38:304–307. © 2004 Wiley‐Liss, Inc.
Pediatric bronchiectasis: Correlation of HRCT, ventilation and perfusion scintigraphy, and pulmonary function testing
Authors: Pifferi Massimo , Caramella Davide , Bulleri Alessandra , Baldi Simonetta , Peroni Diego , Pietrobelli Angelo , Boner Attilio L. 
Published: July 2004

AbstractBronchiectasis in children, although occurring with diminished frequency, continues as a major challenge for the pediatric pulmonologist. The method of choice for the diagnosis of the condition is high‐resolution computed tomography (HRCT). The aim of the present study was to correlate the relationship(s) of HRCT, lung function, ventilation lung scintigraphy (VLS), and perfusion lung scintigraphy (PLS) in children with bronchiectasis. Sixteen children ranging in age from 4–18 years with clinical and chest X‐ray evidence of bronchiectasis were enrolled in the study. The degree of bronchiectasis was assessed by HRCT scores, decrease in attenuation on expiratory scans, VLS, and PLS. HRCT scores for bronchiectasis and decreased lung attenuation showed a strong correlation with PLS (ρ = 0.82; P < 0.001) and with VLS (ρ = 0.72; P < 0.01). There was a moderate negative correlation between FEV1 and HRCT bronchiectasis scores (ρ = −0.53; P = 0.02), decreased lung attenuation score (ρ = −0.64; P = 0.007), and atelectasis score (ρ = −0.54; P = 0.03). In conclusion, HRCT provides a complete and precise assessment of children with bronchiectasis. Ventilation/perfusion scans and lung functions are additive tools to understand the complexity of the disease process and to improve diagnosis and therapeutic strategies. Pediatr Pulmonol. 2004; 38:298–303. © 2004 Wiley‐Liss, Inc.
Theoretical AM1 studies of inclusion complexes of heptakis(2‐O‐hydroxypropyl)‐β‐cyclodextrins with alkylated phenols
Authors: Huang Ming‐Ju , Yi Manyin 
Published: August 2004

AbstractSemiempirical Austin model I (AM1) calculations have been performed on a family of inclusion complexes of heptakis(2‐O‐hydroxypropyl)‐β‐cyclodextrin isomers derived from the 2‐hydroxyl position (2HPβCD) and from the 6‐hydroxyl position (6HPβCD) with alkylated phenol derivatives. From the stabilization energies and hydrogen bonding studies of the inclusion complexes of 2HPβCD and 6HPβCD with substituted phenols in head‐first and tail‐first positions, we found that the main driving forces for the formation of the inclusion complexes are from the van der Waals interactions. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Continuous‐flow sample introduction for field desorption/ionization mass spectrometry
Authors: Schaub Tanner M. , Linden H. Bernhard , Hendrickson Christopher L. , Marshall Alan G. 
Published: July 2004

AbstractWe introduce continuous‐flow field desorption (FD) for improved spectral quality, higher sample throughput, and simpler interface to sample handlers and chromatographic equipment. A recently developed commercial FD probe with integral fused‐silica capillary allows sample dosing in situ, without probe removal and reinsertion. A stable FD‐generated ion current can be sustained for longer than an hour by continuous deposition of analyte solution on the FD emitter heated and at high voltage. Continuous‐flow FD allows ensemble averaging of up to 100 Fourier transform ion cyclotron resonance (FT‐ICR) mass spectra, in contrast to the traditional emitter dosing technique. Continuous‐flow FD is amenable to interface with liquid chromatography (LC) and/or automated sample injectors. Copyright © 2004 John Wiley & Sons, Ltd.
Flow‐rate characterization of microfabricated polymer microspray emitters
Authors: Lion Niels , Gellon Jean‐Olivier , Girault Hubert H. 
Published: July 2004

AbstractMicrofabricated polymer microspray emitters are characterized in terms of applicable flow rates, temporal and spectral signal‐to‐noise ratios (SNRs), and solution composition. First, microspray emitters can be operated with 50% methanol/49% water/1% acetic acid from 250 nL/min up to 7 μL/min, with better SNRs above 1 μL/min. Interestingly, even at the lowest flow rates tested, they compare well with nanospray capillaries in terms of mass spectral performances. Secondly, they can be operated with acetonitrile from 10 up to 99% (v/v), with flow rates from 250 nL/min up to 4 μL/min. Even if the mass spectral performances (especially the spectral SNRs) vary with the acetonitrile content, this study validates such microfabricated microspray emitters as interfaces between liquid‐phase separations and electrospray mass spectrometers. Copyright © 2004 John Wiley & Sons, Ltd.
Trace level quantification of deuterated 17β‐estradiol and estrone in ovariectomized mouse plasma and brain using liquid chromatography/tandem mass spectrometry following dansylation reaction
Authors: Xia Yuan‐Qing , Chang Steve W. , Patel Shefali , Bakhtiar Ray , Karanam Bindhu , Evans David C. 
Published: July 2004

AbstractA sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method coupled with dansylation was developed for the simultaneous quantification of exogenously administered deuterated 17β‐estradiol‐d4 (E2‐d4) and its metabolite, estrone‐d4 (E1‐d4), in mouse plasma and brain homogenates. The dansylation reaction was simple, fast, and sensitive, and a lower limit of quantification of 50 pg/mL was achieved by using 50 μL of mouse plasma. Interference from endogenous 17β‐estradiol and estrone in plasma and brain samples was minimized by the use of deuterated‐E2 as well by utilizing ovariectomized (OVX) mice. The recovery of dansylated derivative exceeded 83% and the reaction was completed within approximately 3 min. The intra‐ and inter‐day assay precision were better than 12.9% and assay accuracy ranged between 92–104% for E1‐d4 and E2‐d4 in plasma, respectively. The absorption of E2‐d4 at both 1 and 3 mg/kg P.O. was rapid, reaching peak plasma concentrations (Cmax) at 5 min post‐dose that was the earliest time point obtained, and were 1.1 and 13.8 ng/mL, respectively; the Cmax values for the estrone metabolite, E1‐d4, were 1.1 and 43.2 ng/mL, respectively. The area‐under‐the‐plasma‐time curve (AUC0‐2h) values were determined to be 0.65 and 2.90 ng · h/mL for E2‐d4 and 0.77 and 6.74 ng · h/mL for E1‐d4, respectively, at 1 and 3 mg/kg. The mean brain‐to‐plasma ratio for E1‐d4 and E2‐d4 after P.O. administration of E2‐d4 to the OVX mice at 1 and 3 mg/kg indicated that both E1‐d4 and E2‐d4 were present in the brain as well as in the circulation. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of alkanolamines in cattails (Typha latifolia) utilizing electrospray ionization with selected reaction monitoring and ion‐exchange chromatography
Authors: Peru Kerry M. , Headley John V. , Doucette William J. 
Published: July 2004

AbstractSelected reaction monitoring (SRM) with electrospray ionization was used as a specific detection technique for the analysis of alkanolamines in plant tissue extracts. Ion‐exchange chromatography was used as the method of separation. Quantification was based on monitoring the loss of either H2O or 2(H2O) from the protonated molecule [M+H]+. The method provided increased selectivity for all analytes and better detection limits for three of the six analytes investigated compared with an earlier method using selected ion monitoring with liquid chromatography. Instrumental detection limits ranged from 6–300 pg injected for monoethanolamine (MEA), monoisopropanolamine (MIPA), diethanolamine (DEA), methyldiethanolamine (MDEA), diisopropanolamine (DIPA), and triethanolamine (TEA). Method robustness and selectivity were demonstrated by the determination of DIPA and a known transformation product MIPA in over 35 plant extract samples derived from a laboratory study of plant uptake mechanisms. Copyright © 2004 John Wiley & Sons, Ltd.
Formation of iminium ions by fragmentation of a2 ions
Authors: Harrison Alex G. , Young Alex B. , Schnoelzer Martina , Paizs Béla 
Published: July 2004

AbstractTandem mass spectrometric experiments have been carried out on the protonated amides H‐Gly‐Ala‐NH2, H‐Ala‐Gly‐NH2, H‐Ala‐Val‐NH2, H‐Val‐Ala‐pNA, H‐Leu‐Phe‐NH2, H‐Phe‐Leu‐NH2, H‐Phe‐Tyr‐NH2 and H‐Tyr‐Phe‐NH2 with particular emphasis on the fragmentation of the isomeric a2 ions derived therefrom. Primary fragmentation reactions of the protonated amides involve formation of the y1″ and b2 ions with further fragmentation of the b2 ion to form the a2 ion which fragments to form iminium ions. Collision‐induced dissociation studies of the mass‐selected a2 ions were carried out. For the Gly‐Ala, Ala‐Gly and Val‐Ala a2 ions, weak signals were observed corresponding to loss of CO from the a2 ion. With the exception of the Gly‐Ala, Ala‐Gly and Val‐Ala a2 ions, both possible iminium ions (a1 and the internal iminium ion) are observed with the most abundant being that formed by proton attachment to the imine of higher proton affinity. The results provide strong support for the recently proposed (El Aribi et al. J. Am. Chem. Soc. 2003; 125: 9229) mechanism of fragmentation of a2 ions which involves elimination of CO from the a2 ion to form a proton‐bound complex of two imines. Based on this mechanism ab initio calculations of the total energies of the a2 ions and the transition states for fragmentation have been carried out giving the energy barrier for fragmentation of each a2 ion. The experimental results are interpreted in terms of these energetics data, unimolecular rate constants calculated by using the RRKM theory, and the imine proton affinities. Copyright © 2004 John Wiley & Sons, Ltd.
RScore: a peptide randomicity score for evaluating tandem mass spectra
Authors: Li Fuxin , Sun Wei , Gao Youhe , Wang Jue 
Published: July 2004

AbstractRScore, a new criterion of randomicity for evaluating tandem mass (MS/MS) spectra, is described. RScore is defined as the relative quality in cross‐correlation and matched intensity percentage of a potentially positive peptide to those of other possible candidates for the same spectrum. By utilizing RScore combined with less stringent SEQUEST score filters, the number of true positive peptides can be increased and the number of false positives in datasets from a known protein mixture can be reduced compared with current SEQUEST parameters used alone. This algorithm is simple and adds little overheads to SEQUEST computation. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of N‐acetyl‐S‐(N‐methylcarbamoyl)cysteine (AMCC) in urine by high‐performance liquid chromatography combined with mass spectrometry
Authors: Perico A. , Baglioni S. , Bavazzano P. 
Published: July 2004

AbstractA simple, sensitive and specific method for the quantification of N‐acetyl‐S‐(N‐methylcarbamoyl)cysteine (AMCC) in urines of the general population and of exposed workers has been developed. Samples were first diluted with phosphate buffer followed by purification by solid‐phase extraction (SPE) with SAX columns prior to analysis by liquid chromatography/mass spectrometry (LC/MS). An external standard was used for the quantification together with selected ion monitoring of m/z 219, [MH]−. The linear calibration curve showed a good correlation (r2 = 0.98, p < 0.001) between 0.1–110 mg/L of AMCC, and the detection limit was calculated to be 2 μg/L. The within‐day and between‐day precision, calculated for exposed workers and general population AMCC levels in urine samples, were determined as 1.2 and 3.6%, respectively (as relative standard deviation (RSD)). Copyright © 2004 John Wiley & Sons, Ltd.
Quantification of hydrogen cyanide in humid air by selected ion flow tube mass spectrometry
Authors: Španěl Patrik , Wang Tianshu , Smith David 
Published: July 2004

AbstractFollowing our recent observation that Pseudomonas bacteria in vitro emit hydrogen cyanide, we have found it necessary to investigate the ion chemistry of this compound and to extend the kinetics database for selected ion flow tube mass spectrometry (SIFT‐MS) to allow the accurate quantification of HCN in moist air samples, including exhaled breath. Because of the proximity of the proton affinities of HCN and H2O molecules, the presence of water vapour can significantly distort HCN analysis in the presence of water vapour and a more sophisticated analytical procedure has to be developed. Thus, the reactions of H3O+(H2O)0,1,2,3 ions with HCN molecules have been studied in the presence of varying concentrations of water vapour, reactions on which SIFT‐MS analysis of HCN relies. The results of these experiments have allowed an analytical procedure to be developed which has extended the kinetics database of SIFT‐MS, such that HCN can now be quantified in humid air and in exhaled breath. Copyright © 2004 John Wiley & Sons, Ltd.
Rapid identification of environmental bacterial strains by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Ruelle Virginie , Moualij Benaissa El , Zorzi Willy , Ledent Philippe , Pauw Edwin De 
Published: August 2004

AbstractIn recent years, various mass spectrometry procedures have been developed for bacterial identification. The accuracy and speed with which data can be obtained by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS) could make this a powerful tool for environmental monitoring. However, minor variations in the sample preparation can influence the mass spectra significantly. Therefore, the first objectives of this study were the adjustment and the optimization of experimental parameters allowing a rapid identification of whole bacterial cells without laborious sample preparation. The tested experimental parameters were matrix, extraction solvent, salt content, deposition method, culture medium and incubation time. This standardized protocol was applied to identify reference and environmental bacterial strains of Escherichia coli, Salmonella and Acinetobacter. The environmental bacterial strains were isolated from sewage sludge using an original microextraction procedure based on repeated sonications and enzymatic treatments. The bacterial identification was realized by the observation of the respective genus‐, species‐ and strain‐specific biomarkers. This bacterial taxonomy could be completed within one hour, with minimal sample preparation, provided that sufficient bacteria had been collected prior to MALDI‐TOF analysis. Copyright © 2004 John Wiley & Sons, Ltd.