bluuebunny/crossref_metadata_2025_split huggingface dataset:
Beetle‐specific Bacillus thuringiensis Cry3Aa toxin reduces larval growth and curbs reproduction in Spodoptera littoralis (Boisd.)
Authors: Hussein Hany M , Habuštová Oxana , Sehnal František 
Published: September 2005

AbstractApplication of Bacillus thuringiensis tenebrionis (Bt) and expression of the Bt protein Cry3Aa in genetically modified crops are used for targeted control of the Colorado potato beetle Leptinotarsa decemlineata (Say). The Cry3A proteins are selectively toxic for the beetles but the present study describes effects of Cry3Aa on the Egyptian armyworm, Spodoptera littoralis (Boisduval). Cry3Aa expressed in potatoes or added to an agar‐base wheat‐germ diet reduced the growth of S. littoralis caterpillars and the fertility of adults. The effect of 1.4 mg kg−1 Cry3Aa in potato leaves was comparable with that of 3.3 mg kg−1 in the diet. This difference in activity was correlated with better digestibility and higher conversion efficiency of the diet that also supported higher reproduction rate: S. littoralis grown on the potatoes reached a similar size to those on the diet but laid only 702 instead of 1077 eggs per female. Cry3Aa consumption reduced body growth as a consequence of lower food intake without significantly affecting food digestibility and the conversion efficiency of nutrients. The 11% and 5% body weight reductions caused by 1.4 mg kg−1 Cry3Aa in potatoes and 3.3 mg kg−1 in the diet, respectively, were associated with 74% and 65% reduction in the number of progeny; S littoralis grown on a diet with 9.1 mg kg−1 Cry3Aa were 10% smaller and produced no viable progeny. These data suggest that the curtailment of reproduction was not caused by a general shortage of nutrient reserves but by a more direct Cry3Aa effect on the reproduction process. Copyright © 2005 Society of Chemical Industry
Self‐organization of para‐sexiphenyl on crystalline substrates
Authors: Hlawacek Gregor , Teichert Christian , Andreev Andrei Yu. , Sitter Helmut , Berkebile Stephen , Koller Georg , Ramsey Michael , Resel Roland 
Published: September 2005

AbstractThe understanding of fundamental growth processes is critical for the fabrication of organic semiconductor thin films to be used in optoelectronic devices. Atomic‐force microscopy is a vital tool to quantitatively analyze the evolving crystalline nanostructures and their spontaneous ordering. Here, para‐sexiphenyl – a semiconducting light emitting oligomer – has been grown epitaxially by different high vacuum and ultra high vacuum methods onto crystalline substrates like mica(001), TiO2(110), or Al(111). Depending on the actual growth parameters, characteristically shaped crystallites composed of lying molecules or terraced mounds of upright standing molecules are formed. With ongoing deposition, quasi 1D arrays of crystallites can evolve due to a rearrangement process of the earlier formed crystallites. For highly anisotropic surfaces, like mica(001) and TiO2(110), these para‐sexiphenyl structures are correlated to the surface geometry of the substrate. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A new method for measurement of (−)‐sophocarpine, a candidate therapeutic for viral myocarditis, in plasma: application to a toxicokinetic study in beagle dogs
Authors: Guo Bin , Li Chuan , Deng Zhongping , Chen Shuxia , Ji Zhouhua , Zhang Junwei , Chen Meifang , Xu Fang 
Published: September 2005

AbstractThe naturally occurring alkaloid (−)‐sophocarpine (SC) has been developed as a novel anti‐coxsackieviral agent for potential treatment of viral myocarditis. However, there is currently no rapid, sensitive method available for ascertaining systemic exposure during the course of SC toxicity studies. The development and full validation of the first rapid and sensitive method, based on liquid chromatography with tandem mass spectrometry (LC/MS/MS), for determination of SC in plasma is reported here. This new assay increases sample throughput by using minimal sample clean‐up procedures and short chromatographic analysis times. The bio‐matrix effect on the ionization of SC and the internal standard, (−)‐stepholidine, was investigated for method development and validation, and two organic solvents (methyl tert‐butyl ether and ethyl acetate) were found for sample preparation that led to low matrix effects. The new analytical method was used to analyze plasma samples obtained from a repeated‐dose toxicity study of SC in beagle dogs. The results of the toxicokinetic analysis indicated that the systemic exposure to SC was proportional to the dose, and that no significant accumulation of SC was observed after 3 months of repeated treatments with intravenous SC at 7.5, 15, or 30 mg/kg/day. This sensitive and specific LC/MS/MS technique can form the basis for accurate quantification of SC in various biological fluids for preclinical and clinical pharmacokinetic evaluation. Copyright © 2005 John Wiley & Sons, Ltd.
Assessment of microwave‐assisted enzymatic digestion by measuring glycated hemoglobin A1c by mass spectrometry
Authors: Vesper Hubert W. , Mi Luchuan , Enada Archibold , Myers Gary L. 
Published: September 2005

AbstractEnzymatic digestion of proteins and analysis of the resulting peptides by mass spectrometry is an established approach in proteomics and in clinical and environmental chemistry. The long digestion times of several hours prevent the fast turnover of samples and results. Qualitative applications showed that microwave radiation profoundly shortens enzymatic digestion. However, its usefulness for quantitative applications had not been assessed. In this study, the microwave‐assisted enzymatic digestion of hemoglobin at different temperatures, buffer concentrations, and digestion times was assessed and compared with conventional digestion for the proteolytic enzymes trypsin and Glu‐C. A microwave‐assisted enzymatic digestion method optimized for digestion time and temperature was applied for the analysis of glycated hemoglobin HbA1c and compared with a reference method. Using trypsin, complete digestion was obtained at 50°C within 20 min. Under these conditions, the digestion efficiency was 20% higher than with conventional trypsin digestion. These effects were not observed with Glu‐C as enzyme, probably because of the decreased stability of Glu‐C at elevated temperatures in comparison with the trypsin used. The comparison of the optimized microwave‐assisted digestion method using trypsin with the reference method for HbA1c using Glu‐C gave a close correlation in the results (R2: 0.996). A significant bias of 0.33% HbA1c was observed, with higher values obtained with the microwave‐assisted tryptic digest; this finding might have resulted from the use of a different enzyme. This study showed that microwave‐assisted enzymatic digestion can substantially reduce digestion times to minutes and can be used in qualitative as well as quantitative applications. Published in 2005 by John Wiley & Sons, Ltd.
Improved sensitivity for quantification of proteins using triply charged cleavable isotope‐coded affinity tag peptides
Authors: Qu Jun , Straubinger Robert M. 
Published: September 2005

AbstractIsotope‐coded affinity tag (ICAT) methods, in conjunction with capillary liquid chromatography/tandem mass spectrometry (LC/MS/MS), represent a promising approach for accurate protein quantification. However, sensitivity remains a challenge for the quantification of low‐copy proteins in complex biological matrices. Here we investigated the electrospray ionization (ESI) and collision‐activated dissociation (CAD) behavior of peptides derivatized with the cleavable ICAT (cICAT) reagent. For cICAT‐peptides that were either synthesized or obtained by digestion of model proteins, the cICAT moiety showed a tendency toward protonation under positive ESI, producing relatively intense triply charged cICAT‐peptide ions ([IP+3H]3+). [IP+3H]3+ exhibited significantly higher CAD reactivity than did the doubly charged cICAT‐peptide ([IP+2H]2+), and produced a greater abundance of fragments at lower collision energies. Fragmentation spectra of [IP+3H]3+ showed variable intensities of doubly charged y and b ions, and the amount of sequence information obtained was dependent on the position of the cICAT‐labeled cysteine residue in the peptide sequence. However, the absolute abundances of major fragments of [IP+3H]3+ were much higher than for [IP+2H]2+. Although the efficiency of identification of cICAT‐peptides was compromised by their charge distribution toward the triply charged state and by the unique CAD behavior of the [IP+3H]3+ ions, it was found that the triply charged ions provided higher sensitivity than [IP+2H]2+ for quantification using multiple reaction monitoring (MRM). ESI and CAD conditions for MRM of [IP+3H]3+ were optimized, and, for all cICAT‐peptides studied, MRM using [IP+3H]3+ as precursors showed 2‐ to 8‐fold higher sensitivity than obtained using [IP+2H]2+, without compromising quantitative accuracy. Using this approach, the time course of tyrosine aminotransferase induction by methylprednisolone was monitored in rat livers. A remarkably better signal‐to‐noise ratio was observed by using [IP+3H]3+ for quantification compared to [IP+2H]2+. Copyright © 2005 John Wiley & Sons, Ltd.
Approaches to fitting age‐period‐cohort models with unequal intervals
Authors: Holford Theodore R. 
Published: September 2005

AbstractAge‐period‐cohort models have provided useful insights into the analysis of time trends for disease rates, in spite of the well known identifiability problem. Unique parameter estimates that avoid arbitrary constraints are provided by estimable functions of the parameter estimates. For data that are generated using equal interval widths for age and period, the identifiability issue may be expressed in terms of the age, period and cohort slopes. However, when the interval widths are not the same for age and period, additional identifiability problems arise. These may be represented in terms of macro‐trends, which have the identical identifiability problem seen in the equal interval case, and micro‐trends, which are the source of the additional problems. A framework for testing estimability is presented, and a variety of potentially interesting functions of the parameters considered. Unlike the equal interval case, drift is not estimable for unequal intervals, but local drift may be. In addition, the available functions for forecasting are much more restrictive in the latter case. This estimability problem induces cyclical patterns in the estimates of trend as is demonstrated using data on leukaemia in Connecticut males, but this can be avoided through the use of smoothing splines. These methods of are illustrated for three‐year period and five‐year age intervals using data on lung cancer mortality in Californian women. Copyright © 2005 John Wiley & Sons, Ltd.
Probabilistic index: an intuitive non‐parametric approach to measuring the size of treatment effects
Authors: Acion Laura , Peterson John J. , Temple Scott , Arndt Stephan 
Published: September 2005

AbstractEffect sizes (ES) tell the magnitude of the difference between treatments and, ideally, should tell clinicians how likely their patients will benefit from the treatment. Currently used ES are expressed in statistical rather than in clinically useful terms and may not give clinicians the appropriate information. We restrict our discussion to studies with two groups: one with n patients receiving a new treatment and the other with m patients receiving the usual or no treatment. The standardized mean difference (e.g. Cohen's d) is a well‐known index for continuous outcomes. There is some intuitive value to d, but measuring improvement in standard deviations (SD) is a statistical concept that may not help a clinician. How much improvement is a half SD? A more intuitive and simple‐to‐calculate ES is the probability that the response of a patient given the new treatment (X) is better than the one for a randomly chosen patient given the old or no treatment (Y) (i.e. P(X > Y), larger values meaning better outcomes). This probability has an immediate identity with the area under the curve (AUC) measure in procedures for receiver operator characteristic (ROC) curve comparing responses to two treatments. It also can be easily calculated from the Mann–Whitney U, Wilcoxon, or Kendall τ statistics. We describe the characteristics of an ideal ES. We propose P(X > Y) as an alternative index, summarize its correspondence with well‐known non‐parametric statistics, compare it to the standardized mean difference index, and illustrate with clinical data. Copyright © 2005 John Wiley & Sons, Ltd.
Effective number of subjects and number of raters for inter‐rater reliability studies
Authors: Saito Yuki , Sozu Takashi , Hamada Chikuma , Yoshimura Isao 
Published: September 2005

AbstractA reliability study in which multiple raters evaluate multiple subjects was assumed in order to confirm the inter‐rater reliability of rating scales. The two‐way ANOVA model defining subjects and raters as random effects was applied, and the combination of the number of subjects and the number of raters that minimizes variance of the intraclass correlation coefficient (ICC) with a fixed total number of ratings (number of subjects × number of raters) was studied. The results revealed that the optimal combination depends on the relative ratio (between‐rater variance/error variance), and that large number of raters brings the high precision of estimation of the ICC when the relative ratio was greater. It was concluded that when information concerning the relative ratio is unreliable, the use of identical numbers of raters and subjects minimizes variance when the relative ratio is substantially large and variance is maximized, providing a good study design from the viewpoint of ‘maximin’. Copyright © 2005 John Wiley & Sons, Ltd.
Exploring series of multivariate censored temporal data through fuzzy coding and correspondence analysis
Authors: Goldfarb Bernard , Pardoux Catherine M. 
Published: September 2005

AbstractWe present an exploratory analysis methodology for a multiple series of multivariate temporal data subject to censoring, and thus requiring the introduction of a coding technique: fuzzy coding preserving a large amount of the distributional information is fully adapted. Correspondence analysis is performed on the array produced by fuzzy coding. Projections of mean paths on factorial mappings, according to subgroup characteristics, highlight the behaviour of the underlying process. This approach is illustrated with an application to a randomized controlled clinical trial designed for comparing non‐diabetic chronic renal failure treatments. Our methodology has resulted in the identification of a difference between the treatments with an interpretation of the effects in subgroups of patients not obtainable with traditional survival methodology; it also provides some valuable insights for designing further studies on treatment of renal impairment. Copyright © 2005 John Wiley & Sons, Ltd.
A score test for zero‐inflation in correlated count data
Authors: Xiang Liming , Lee Andy H. , Yau Kelvin K. W. , McLachlan Geoffrey J. 
Published: September 2005

AbstractTo account for the preponderance of zero counts and simultaneous correlation of observations, a class of zero‐inflated Poisson mixed regression models is applicable for accommodating the within‐cluster dependence. In this paper, a score test for zero‐inflation is developed for assessing correlated count data with excess zeros. The sampling distribution and the power of the test statistic are evaluated by simulation studies. The results show that the test statistic performs satisfactorily under a wide range of conditions. The test procedure is further illustrated using a data set on recurrent urinary tract infections. Copyright © 2005 John Wiley & Sons, Ltd.
An interval scale for development of children aged 0–2 years
Authors: Jacobusse Gert , van Buuren Stef , Verkerk Paul H. 
Published: September 2005

AbstractMeasurement of development is often less precise than that of height and weight. Developmental scores are typically based on passing one or more developmental markers, but do not have interval scale so calculating differences between scores can be nonsensical. Age‐specific standardized scores are sometimes used, but fail to have a common metric that allows comparison of developmental scores across age. The goal of this study is to develop a quantitative developmental score (D‐score) with improved measurement characteristics. The basic assumption of the D‐score is the existence of a common continuous scale for the development. Scores of 2151 children between 0 and 2 years on a Dutch developmental instrument were analysed. Application of the Rasch Model resulted in excellent reliability and satisfactory fit. This indicates that the new quantitative D‐score succeeds in representing outcomes of the instrument on a common interval scale. Age‐conditional reference values for the D‐score were derived by means of the LMS method. The definition of the D‐scores is not specific to age, so the D‐score of a measured person can be compared to the D‐score of another person of a different age. Difference scores between sessions can be used to evaluate developmental velocity on the individual level. To our knowledge this is the first developmental scale for children with such properties. Copyright © 2005 John Wiley & Sons, Ltd.
Targeted mid‐trimester ultrasound examination: how does fetal anatomic visualization depend upon the duration of the scan?
Authors: Catanzarite V. , Delaney K. , Wolfe S. , Dowling D. , Daneshmand S. , Cousins L. , Poeltler D. 
Published: September 2005

AbstractObjectiveTo determine the relationship between visualization of key fetal anatomic structures during mid‐trimester ultrasound examination with gestational age and duration of examination.MethodsOne hundred ultrasound examinations at 16–22 weeks' gestation were reviewed to determine the times at which key fetal anatomic features were seen. Scans were terminated at 30 min or when a comprehensive anatomic survey was complete. Exclusion criteria included multiple gestation, maternal weight > 77 kg, abdominal wall scarring, and suspected fetal anomalies.ResultsVisualization of cranial anatomy including lips, face, midline, ventricles, choroid plexus, and cerebellum was achieved in 98% of patients within 30 min. The corresponding figures for spine, cardiac screening (four‐chamber, aortic, and pulmonary outflow views) and for abdominal anatomy (stomach, kidneys, bladder, ventral wall, and three‐vessel cord) were 91%, 91%, and 99%, respectively. A complete anatomic survey including each of the above elements was obtained by 10, 15, 20, 25, and 30 min in 8%, 31%, 53%, 72% and 81% of the subjects. Rates of complete anatomic surveys within 30 min improved by gestational age interval, from 20/30 (67%) at 16–18 weeks, to 36/44 (82%) at 18–20 weeks, and 25/26 (96%) at 20–22 weeks; this rise was primarily due to improvements in visualization of the spine and heart.ConclusionsA comprehensive anatomical survey can be completed in 10 min or less in a minority of patients. For each 5‐min time increment up to 30 min, the rate of complete surveys improves. Rates of completed anatomic surveys rise with gestational age. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Fetal trunk and head volume in chromosomally abnormal fetuses at 11 + 0 to 13 + 6 weeks of gestation
Authors: Falcon O. , Peralta C. F. A. , Cavoretto P. , Auer M. , Nicolaides K. H. 
Published: September 2005

AbstractObjectiveTo examine the pattern of growth in chromosomally abnormal fetuses at 11 + 0 to 13 + 6 weeks of gestation and compare the trunk and head volume to crown–rump length (CRL) in defining the growth deficit in such fetuses.MethodsThe fetal trunk and head volume was measured using three‐dimensional (3D) ultrasound in 140 chromosomally abnormal fetuses at 11 + 0 to 13 + 6 (median 12) weeks of gestation, and the values were compared to 500 chromosomally normal fetuses. In each chromosomally abnormal fetus, the observed fetal trunk and head volume was subtracted from the expected mean (delta value) of the chromosomally normal fetuses of the same gestational age, and this difference was expressed as a percentage of the appropriate normal mean. The Mann–Whitney U‐test was used to determine the significance of differences between the chromosomally normal and abnormal groups.ResultsIn trisomy 21 (n = 72) and Turner syndrome (n = 14) fetuses, compared to chromosomally normal fetuses, the CRL for gestation was similar (P = 0.335 and P = 0.317, respectively), but the fetal trunk and head volume was about 10–15% lower (P < 0.001 and P = 0.004, respectively). In trisomy 18 (n = 29), trisomy 13 (n = 14) and triploidy (n = 11), the deficit in volume was about 45% (P < 0.001), whereas the deficit in CRL was less than 15% (P < 0.001).ConclusionsIn the quantification of the degree of early growth impairment in chromosomally abnormal fetuses, measurement of the fetal trunk and head volume using 3D ultrasound may be better than measurement of CRL. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Development of a K‐shell x‐ray fluorescence measurement of cadmium in bone
Authors: Carew S. E. , Gastaldo J. , Roels H. A. , O'Meara J. M. , Chettle D. R. 
Published: September 2005

AbstractCadmium is known to accumulate in the human body and chronic exposures have been clearly linked to adverse health effects, showing the kidney as the critical target organ. However, there is evidence of an association between extensive environmental exposure to cadmium and alterations in bone/calcium metabolism. Therefore, it is desirable to be able to measure bone cadmium non‐invasively in humans. Tibia was selected as a measurement site and source‐excited K‐shell x‐ray fluorescence was investigated both experimentally and computationally. Initially the 88 keV γ‐rays from 109Cd were used to assess minimum detectable level (MDL) of cadmium in phantoms comprising plaster of Paris (bone) and wax (soft tissue). An MDL of 3–4µg g−1 was achieved for overlying tissue thicknesses of up to 5 mm. Alternative sources were 125I and 241Am. Monte Carlo simulation showed that the spectral contrast for 125I would be poor. The 60 keV γ‐rays from 241Am were more promising, provided that the 26 keV γ‐rays were filtered out. Experiments with 241Am confirmed that a lower MDL could be achieved. However, the product of MDL and square root of dose (a figure of merit) was not improved. Since effective doses for these source‐excited x‐ray fluorescence procedures are low (typically of the order of 0.1 µSv or less), it may be that lower MDL would be preferred over lower dose. Nevertheless, development continues as a further reduction in MDL is highly desirable. Copyright © 2005 John Wiley & Sons, Ltd.