bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a rapid and specific assay for detection of busulfan in human plasma by high‐performance liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: dos Reis Ederson Oliveira , Vianna‐Jorge Rosane , Suarez‐Kurtz Guilherme , Lima Edson Luiz da Silva , Azevedo Débora de Almeida 
Published: May 2005

AbstractA sensitive and specific assay for detection of busulfan in human plasma was developed. The assay is based on rapid isolation of busulfan by liquid‐liquid extraction with ethyl acetate, and detection by high‐performance liquid chromatography with electrospray ionization and tandem mass spectrometry. 1,6‐Bis(methanesulfonyloxy)hexane, a synthesized analogue of busulfan, was used as the internal standard (IS). The acquisition was performed in the multiple reaction monitoring mode; busulfan and the IS were detected with no interferences from plasma matrix. The method was linear over the range 5–2500 ng mL−1, with r2 > 0.99 and a run time of only 3.5 min. The intra‐ and inter‐assay precisions were in the ranges 2.1–11.9% and 3.2–10.1%, respectively, and the intra‐ and inter‐assay accuracies were 92.2–107.6% and 94.7–104.1%, respectively. The absolute recoveries were 82.0% (20 ng mL−1), 90.6% (1000 ng mL−1) and 80.0% (2000 ng mL−1) for busulfan, and 89.1% for the IS (1000 ng mL−1). The limits of detection and quantification were 2 and 5 ng mL−1, respectively. The validated method was successfully applied to analyze plasma samples obtained from six adults receiving doses of 1 mg kg−1 in a conditioning regimen prior to bone marrow transplantation. A marked intra‐patient variation in busulfan concentrations during the steady state was observed, which limits the application of pharmacokinetic modeling and suggests that continuous therapeutic monitoring is necessary for adequate individualized dosing. In this regard, the present assay brings important advantages relative to other methods described in the literature, i.e., it is highly specific and simple to perform, with a rapid chromatographic run time (3.5 min), and the whole procedure can be completed in 4–5 h, which would permit dose corrections after the third dose allowing earlier and better dosing adjustments towards the target level of busulfan. Copyright © 2005 John Wiley & Sons, Ltd.
Peptide photodissociation at 157 nm in a linear ion trap mass spectrometer
Authors: Kim Tae‐Young , Thompson Matthew S. , Reilly James P. 
Published: May 2005

AbstractThe photodissociation by 157 nm light of singly‐ and doubly‐charged peptide ions containing C‐ or N‐terminal arginine residues was studied in a linear ion trap mass spectrometer. Singly‐charged peptides yielded primarily x‐ and a‐type ions, depending on the location of the arginine residue, along with some related side‐chain fragments. These results are consistent with our previous work using a tandem time‐of‐flight (TOF) instrument with a vacuum matrix‐assisted laser desorption/ionization (MALDI) source. Thus, the different internal energies of precursor ions in the two experiments seem to have little effect on their photofragmentation. For doubly‐charged peptides, the dominant fragments observed in both photodissociation and collisionally induced dissociation (CID) experiments are b‐ and y‐type ions. Preliminary experiments demonstrating fragmentation of multiply‐charged ubiquitin ions by 157 nm photodissociation are also presented. Copyright © 2005 John Wiley & Sons, Ltd.
Iodoacetamide‐alkylated methionine can mimic neutral loss of phosphoric acid from phosphopeptides as exemplified by nano‐electrospray ionization quadrupole time‐of‐flight parent ion scanning
Authors: Krüger Ralf , Hung Chien‐Wen , Edelson‐Averbukh Marina , Lehmann Wolf D. 
Published: May 2005

AbstractFormation of S‐carbamidomethylmethionine (camMet) occurs as a side reaction during cysteine alkylation with iodoacetamide (IAA). In collision‐induced dissociation, peptides with camMet show an abundant neutral loss of 2‐(methylthio)acetamide (C3H7NOS = 105.025 Da) at moderate collision offset values which are similar to those optimal for loss of phosphoric acid (H3PO4 = 97.977 Da). Neutral loss analysis is used for spotting of phosphopeptides which contain phosphoserine (pSer) or phosphothreonine (pThr) residues. In the case where precursor ions cannot be accurately assigned in the survey spectrum (e.g. due to low ion abundance or signal overlap), the mass accuracy of a neutral loss tandem mass spectrometry (MS/MS) analysis depends on the precursor ion isolation window. For the charge states 2+, 3+ or 4+, a typical 3.5 Da precursor isolation window results in neutral loss windows of 7, 10.5 or 14 Da, respectively. Consequently, neutral loss of 105 Da from alkylated methionine residues can mimic the phosphoserine/phosphothreonine‐specific neutral loss of 98 Da. In the evaluation of quadrupole time‐of‐flight (QTOF) parent ion scan data for neutral loss of H3PO4, this interference was frequently observed. It is illustrated in this study using the analysis of ovalbumin phosphorylation as an example. The +80 Da molecular weight shift connected with phosphorylation at serine or threonine may also be mimicked by carbamidomethylation of methionine through a combination with sodium adduction (+57 Da +22 Da = +79 Da). For highly sensitive neutral loss analysis of serine and threonine phosphorylation, careful data inspection is recommended if reduction and alkylation by IAA is employed. Copyright © 2005 John Wiley & Sons, Ltd.
Matrix‐assisted laser desorption/ionization mass spectrometry of collected bioaerosol particles
Authors: Kim Jae‐Kuk , Jackson Shelley N. , Murray Kermit K. 
Published: May 2005

AbstractA method was developed for collection and analysis of bioaerosols by matrix‐assisted laser desorption/ionization (MALDI) time‐of‐flight mass spectrometry using a modified Andersen N6 bioaerosol collector. The overall goal of the study was to develop methods for obtaining mass spectra with minimal reagents and treatment steps for potential use in remote collection and analysis systems. Test bioaerosol particles were generated from a nebulized E. coli bacterial suspension and collected on MALDI targets placed in an Andersen N6 single‐stage aerosol impactor. The bioaerosols were mixed with matrix either by deposition on a bare target with the matrix solution added later, or by deposition on a target pre‐coated with matrix. The matrix compounds α‐cyano‐4‐hydroxycinnamic acid (CHCA) and sinapic acid (SA) were tested and the SA matrix was found to give the best results in number of peaks, resolution, and signal‐to‐noise ratio. Deposition of bioaerosol particles onto the matrix pre‐coated target did not produce signal in the m/z region above 1000, but the signal could be recovered with the addition of a 1:1 (v/v) acetonitrile/water solvent. Addition of solvent by pipette to the pre‐coated targets after particle deposition recovered signal comparable to the dried‐droplet sample preparations, whereas solvent sprayed into the impactor recovered fewer peaks. Deposition on pre‐coated targets with post‐collection solvent addition was superior to deposition on bare target followed by post‐collection addition of matrix solution. Copyright © 2005 John Wiley & Sons, Ltd.
Quantitative determination of cetirizine enantiomers in guinea pig plasma, brain tissue and microdialysis samples using liquid chromatography/tandem mass spectrometry
Authors: Gupta Anubha , Jansson Britt , Chatelain Pierre , Massingham Roy , Hammarlund‐Udenaes Margareta 
Published: May 2005

AbstractSensitive enantioselective liquid chromatographic assays using tandem mass spectrometric detection were developed and validated for the determination of S‐cetirizine (S‐CZE) and R‐cetirizine (R‐CZE) in guinea pig plasma, brain tissue, and microdialysis samples. Enantioselective separation was achieved on an α1‐acid glycoprotein column within 14 min for all methods. A cetirizine analog, ucb 20028, was used as internal standard. Cetirizine and the internal standard were detected by multiple reaction monitoring using transitions m/z 389.1 → 200.9 and 396.1 → 276.1, respectively. The samples were prepared using protein precipitation with acetonitrile. For guinea pig plasma, the assay was linear over the range 0.25–5000 ng/mL for both S‐CZE and R‐CZE, with a lower limit of quantification (LLOQ) of 0.25 ng/mL. For the brain tissue and microdialysis samples, the assays were linear over the range 2.5–250 ng/g and 0.25–50 ng/mL, respectively, and the LLOQ values were 2.5 ng/g and 0.25 ng/mL, respectively. The intra‐ and inter‐day precision values were ≤7.1% and ≤12.6%, respectively, and the intra‐ and inter‐day accuracy varied by less than ±8.0% and ±6.0% of the nominal value, respectively, for both enantiomers in all the matrices investigated. Copyright © 2005 John Wiley & Sons, Ltd.
Probabilistic behavior of asymmetric level compressed tries
Authors: Devroye Luc , Szpankowski Wojcieh 
Published: May 2005

AbstractLevel‐Compressed (in short LC) tries were introduced by Andersson and Nilsson in 1993. They are compacted versions of tries in which, from the top down, maximal height complete subtrees are level compressed. We show that when the input consists of n independent strings with independent Bernoulli (p) bits, p ≠ 1/2, then the expected depth of a typical node is in probability asymptotic to

where H − p log p − (1 − p) log (1 − p) is the Shannon entropy of the source, and H−∞ = log (1 / min(p, 1 − p)). The height is in probability asymptotic to

where H2 = log(1/(p2 + (1−p)2)). © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005
Maximum weight independent sets and matchings in sparse random graphs. Exact results using the local weak convergence method
Authors: Gamarnik David , Nowicki Tomasz , Swirszcz Grzegorz 
Published: May 2005

AbstractLetG(n,c/n) andGr(n) be ann‐node sparse random graph and a sparse randomr‐regular graph, respectively, and letI(n,r) andI(n,c) be the sizes of the largest independent set inG(n,c/n) andGr(n). The asymptotic value ofI(n,c)/nasn→ ∞, can be computed using the Karp‐Sipser algorithm whenc≤e. For random cubic graphs,r= 3, it is only known that .432 ≤ lim infnI(n,3)/n≤ lim supnI(n,3)/n≤ .4591 with high probability (w.h.p.) asn→ ∞, as shown in Frieze and Suen [Random Structures Algorithms 5 (1994), 649–664] and Bollabas [European J Combin 1 (1980), 311–316], respectively. In this paper we assume in addition that the nodes of the graph are equipped with nonnegative weights, independently generated according to some common distribution, and we consider instead the maximum weight of an independent set. Surprisingly, we discover that for certain weight distributions, the limit limnI(n,c)/ncan be computed exactly even whenc>e, and limnI(n,r)/ncan be computed exactly for somer≥ 1. For example, when the weights are exponentially distributed with parameter 1, limnI(n,2e)/n≈ .5517, and limnI(n,3)/n≈ .6077. Our results are established using the recently developedlocal weak convergencemethod further reduced to a certainlocal optimalityproperty exhibited by the models we consider. We extend our results to maximum weight matchings inG(n,c/n) andGr(n). For the case of exponential distributions, we compute the corresponding limits for everyc> 0 and everyr≥ 2. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2006
Prenatal diagnosis of horseshoe kidney by measurement of the renal pelvic angle
Authors: Cho J. Y. , Lee Y.‐H. , Toi A. , Macdonald B. 
Published: May 2005

AbstractObjectiveThe aim of this study was to evaluate the usefulness of measurement of the angle between bilateral renal pelves on axial views in the prenatal ultrasonographic diagnosis of horseshoe kidney.MethodsWe retrospectively measured the renal pelvic angle in 19 fetuses with horseshoe and 20 fetuses with normal kidneys in the second and third trimesters. Renal pelvic angle was defined as the angle between the long axis of the renal pelves on the axial view of the abdomen. We compared the renal pelvic angles of horseshoe and normal kidneys with unpaired t‐test. Taking 140° as a cut‐off value, we calculated the sensitivity, specificity and accuracy of pelvic angle measurement for the prenatal diagnosis of horseshoe kidney.ResultsThe mean pelvic angles in the fetuses with horseshoe kidney were 116° and 110° in the second and third trimester, respectively. In the normal fetuses, the equivalent angles were 172° and 161°. The difference between the two groups was statistically significant (P < 0.01). Using 140° as the discriminating criterion, the sensitivity, specificity and accuracy of renal pelvic angle measurement for the prenatal diagnosis of horseshoe kidney were all 100%. Fifteen of 19 fetuses with horseshoe kidney had no other abnormality. Four (21%) fetuses had severe complex abnormalities which were associated with trisomy 18 in three cases.ConclusionObservation and measurement of the renal pelvic angle is a simple and useful method in the prenatal diagnosis of the horseshoe kidney. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
A new three‐dimensional automatic bodymarker system for transvaginal ultrasonography
Authors: Kuwata T. , Taniguchi N. , Matsubara S. , Ono T. , Itoh K. , Suzuki M. 
Published: May 2005

AbstractObjectiveTo evaluate the accuracy and usefulness of a newly developed three‐dimensional automatic bodymarker system for transvaginal ultrasonography.MethodsA bodymarker system which utilizes an electromagnetic field to specify the probe position was developed. Software was written which enabled the positional information of the probe and the ultrasound image to be simultaneously displayed on a personal computer. The bodymarker was displayed as a three‐dimensional graphic model. The differences between the estimated and the actual position—i.e. the error—for both position (x, y and z) and angles (azimuth, elevation and roll) of the probe were measured. The movement of the probe was then evaluated in healthy female volunteers and the comparative time required for ultrasound examination was determined.ResultsBoth the position and the angles of the probe were accurately shown in the computer display. The errors were 1.0 mm and 0.7° (median) for position and angle, respectively. The system was also shown to work well in healthy female volunteers. Calibration of the new system required only 5.0 seconds, compared with an average of 7.6 seconds for the conventional bodymarker.ConclusionThe newly developed three‐dimensional automatic transvaginal bodymarker system provides an accurate indication of probe position and its tilting angle. It works well in healthy female volunteers and speeds up the examination time. It may be clinically useful for transvaginal ultrasound examination. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Unexpected intrauterine death following resolution of hydrops fetalis after betamethasone treatment in a fetus with a large cystic adenomatoid malformation of the lung
Authors: Leung W. C. , Ngai C. , Lam T. P. W. , Chan K. L. , Lao T. T. , Tang M. H. Y. 
Published: May 2005

AbstractWithout intervention, the development of hydrops fetalis secondary to cystic adenomatoid malformation of the lung (CAML) implies a 100% mortality rate. Conversely, four CAML cases with in‐utero resolution of hydrops fetalis after prenatal betamethasone therapy with good clinical outcome have been reported in the literature. The mechanism is speculated to be the effect of corticosteroid in improving lung maturation. Here we present another CAML case with resolution of hydrops fetalis after prenatal betamethasone therapy but which was followed by later intrauterine death. We speculate that the resolution of the CAML lesion itself may be more important in determining the clinical outcome than the resolution of hydrops. The association between prenatal betamethasone therapy and resolution of hydrops may be related to a different mechanism other than improvement of lung maturation. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
The equations of a viscous asymmetric fluid: An interactive approach
Authors: Rojas‐Medar M.A. , Ortega‐Torres E.E. 
Published: May 2005

AbstractIn this work we present a new proof of the existence and uniqueness of strong solutions for the equations of a viscous asymmetric fluids. We use an interactive approach and we prove that the approximate solutions constructed by using this method converge to a strong solution of these equations. We also give convergence‐rate bounds for this method.
Analysis and improvement of a perturbation solution for hydraulic flow in a rotating parabolic channel
Authors: Laanearu J. , Lundberg P. 
Published: May 2005

AbstractPower series solutions are presented for a problem within rotating hydraulics. A variety of techniques has been used to investigate and improve the convergence of the expansions. The locations of the dominating singularities affecting the convergence properties of the perturbative series were determined using the Domb‐Sykes ratio test as well as a Padé‐approximant method. Hereafter conformal mapping and series reversion have been applied to extend the parametric range of utility of the series and to accelerate their convergence.
Open‐loop stable solutions of periodic optimal control problems in robotics
Authors: Mombaur K.D. , Bock H.G. , Schlöder J.P. , Longman R.W. 
Published: May 2005

AbstractWe present a numerical method that optimizes the open‐loop stability of solutions of periodic optimal control problems. We consider general periodic processes that may have several phases, each characterized by its own set of differential equations, and discontinuities of the state variables and the right hand side between phases. Stability is measured in terms of the spectral radius of the monodromy matrix which results in a nonsmooth optimization criterion. We have applied this method to design walking robots that can perform stable periodic gaits without any sensors or feedback; three such examples are presented in this paper.
On the contact reaction in a solid circular plate simply supported along an edge arc and deflected by a central transverse concentrated force
Authors: Monegato G. , Strozzi A. 
Published: May 2005

AbstractA static, purely flexural mechanical analysis is presented for a Kirchhoff solid circular plate, deflected by a transverse central force, and bilaterally supported along a single periphery arc, the remaining part of the boundary being free. The contact reaction is assumed to be formed by a distributed reaction force accompanied by a distributed moment with radial axis. This plate problem is formulated in terms of an integral equation of the Prandtl type, supplemented by a vertical and a rotational equilibrium condition. It is shown that the Prandtl equation coupled to the equilibrium condition possesses a unique solution in a proper scale of weighted Sobolev‐type spaces, with certain smoothness properties, and that no solution exists if the distributed moment is absent. Finally, the behaviour of the solution at the endpoints of the support is clarified.
Effect of Treadmill Testing and Exercise Training on Self-Efficacy in Patients with Heart Failure
Authors: Oka Roberta K. , DeMarco Teresa , Haskell William L. 
Published: May 2005

Background: Self-efficacy is a person's confidence in being able to successfully perform a specific activity or behavior. Self-efficacy has been shown to influence exercise capacity in patients post myocardial infarction, but has not been fully explored in patients with heart failure (HF). This study examined the impact of performance of a single treadmill exercise test and participation in a 3-month program of walking and resistance exercise on self-efficacy in HF patients.Methods: 24 patients were randomized to either a home-based walking and resistance exercise program or usual care for 3 months. Prior to enrollment into the exercise program all participants performed a single treadmill exercise test with respiratory gas analysis. Self-efficacy questionnaires were completed at 3 time points, 1) prior to performance of an exercise treadmill test; 2) immediately after completing an exercise test; and 3) at the end of a 3-month exercise program.Results: Self-efficacy for walking ( p = 0.07), climbing ( p = 0.17), lifting ( p = 0.73) and general activity ( p = 0.15) did not improve after performance of a single treadmill exercise test and usual care. However, self-efficacy for walking increased after 3 months of a walking and resistance exercise program. ( p = 0.04).Conclusions: The findings from this study suggest that in patients with stable mild to moderate heart failure, self-efficacy is improved with participation in a home-based walking and endurance exercise program. Self-efficacy is not enhanced by performance of a single treadmill exercise test and usual care.
Vitamins C and E in the latency period in women with preterm premature rupture of membranes
Authors: Borna S. , Borna H. , Daneshbodie B. 
Published: May 2005

AbstractObjective: To determine whether supplementation with vitamins C and E after preterm premature rupture of membranes (PPROM) is associated with an increased latency period. Methods: In this double‐blind, randomized, controlled trial, 60 women with singleton pregnancies of 26 to 34 weeks' duration and PPROM were randomly assigned to vitamin C (500 mg/day) and vitamin E (400 IU/day) or placebo until delivery. All women received 2 doses of betamethasone in the first 24 h after admission as well as broad‐spectrum antibiotic prophylaxis. Results: Important demographic, as well as clinical characteristics such as number of cases of chorioamnionitis, early neonatal sepsis, and respiratory distress syndrome, were similar in the 2 groups. A statically significant difference in the mean ± S.D. number of days of latency was found between the groups (10.5 ± 5.2 days vs. 3.5 ± 4.0 days (P = 0.03). Conclusion: Vitamins C and E supplementation of after PPROM is associated with a longer latency before delivery.
Velamentous cord insertion and atypical variable decelerations with no accelerations
Authors: Hasegawa J. , Matsuoka R. , Ichizuka K. , Sekizawa A. , Farina A. , Okai T. 
Published: May 2005

AbstractObjectives: To examine intrapartum fetal heart rate (FHR) patterns in the presence of velamentous cord insertion (VCI). Methods: The site of cord insertion was determined in 1460 women on antenatal ultrasonographic and postnatal examinations. Each of 24 women with pregnancies complicated with VCI was matched at the onset of labor with 10 women who had a normal pregnancy, and FHR patterns were analyzed for both cases and controls. Results: Compared with controls, cases of variable decelerations with no accelerations (VDNA) during the first and second stages of labor were more frequent in women with VCI (first stage: 25% vs. 5.1%, second stage: 65.0% vs. 21.7%, P < 0.001). The adjusted odds ratio associated with VDNA occurrence in women with VCI was 3.83 (95% confidence interval [CI]: 1.51–9.72, P = 0.005). The mean odds ratio associated with length of aberrant vessels in women with VCI plus VDNA was 1.38 (95% CI: 1.04–1.83, P = 0.026). Conclusion: Pregnancies complicated with VCI are associated with a higher rate of VDNA.
A PROBABILISTIC REPRESENTATION FOR THE VORTICITY OF A THREE-DIMENSIONAL VISCOUS FLUID AND FOR GENERAL SYSTEMS OF PARABOLIC EQUATIONS
Authors: Busnello Barbara , Flandoli Franco , Romito Marco 
Published: May 2005

AbstractA probabilistic representation formula for general systems of linear parabolic equations, coupled only through the zero-order term, is given. On this basis, an implicit probabilistic representation for the vorticity in a three-dimensional viscous fluid (described by the Navier–Stokes equations) is carefully analysed, and a theorem of local existence and uniqueness is proved. The aim of the probabilistic representation is to provide an extension of the Lagrangian formalism from the non-viscous (Euler equations) to the viscous case. As an application, a continuation principle, similar to the Beale–Kato–Majda blow-up criterion, is proved.