bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prenatal diagnosis of free sialic acid storage disorders (SASD)
Authors: Aula Nina , Aula Pertti 
Published: May 2006

AbstractFree sialic acid storage disorders, Salla disease (SD) and Infantile sialic acid storage disease (ISSD), are lysosomal storage diseases due to impaired function of a sialic acid transporter, sialin, at the lysosomal membrane. Several mutations of the sialin gene, SLC17A5, are known, leading either to the severe neonatal/infantile disease or to the milder, adult‐type developmental disorder, Salla disease. Free sialic acid accumulation in lysosomes causes increased tissue concentration and consequently elevated urinary excretion. Prenatal diagnosis of SASD is possible either by determination of free sialic acid concentration or by mutation analysis of the SLC17A5 gene in fetal specimen, in chorionic villus biopsy particularly. Both techniques have been successfully applied in several cases, sialic acid assay more often in ISSD cases but mutation analysis preferentially in SD. Sialic acid assay of amniotic fluid supernatant or cultured amniotic fluid cells may give erroneous results and should not be used for prenatal diagnosis of these disorders. The present comments are mainly based on our experience of prenatal diagnosis of SD in Finnish families. A founder mutation in SLC17A5 gene, 115C‐> T, represents 95% of the disease alleles in the Finnish SD patients, which provides a unique possibility to apply mutation analysis. Therefore, molecular studies have successfully been used in 17 families since the identification of the gene and the characterization of the SD mutations. Earlier, eight prenatal studies were performed by measuring the free sialic acid concentration in chorionic villus samples. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnostic indicators of paternal uniparental disomy 14
Authors: Curtis Logos , Antonelli Eric , Vial Yvan , Rimensberger Peter , Le Merrer Martine , Hinard Christine , Bottani Armand , Fokstuen Siv 
Published: May 2006

AbstractObjectivesTo present clinical findings of a child with paternal uniparental isodisomy 14 (pat UPD14) focusing on relevant prenatal characteristics.Methods/ResultsUltrasonography at 23 weeks of gestation of a 37‐year‐old multigravid woman revealed a fetus with polyhydramnios, small thorax, and short, distinctively angled ribs. Fetal karyotype was 46,XY. The child was born spontaneously at 35 weeks with poor neonatal adaptation. From birth, he presented with severe respiratory insufficiency due to severe thoracic malformation. Clinical examination revealed a small, bell‐shaped thorax, redundant lax skin, mild contractures of the fingers and dysmorphic facial features. Chest X rays showed short, abnormally curved ribs that suggested the possibility of pat UPD14, which was confirmed by molecular analysis.ConclusionPat UPD14 is associated with a distinct clinical phenotype. Prognosis is poor because of severe respiratory insufficiency and neurodevelopmental retardation. Our report confirms salient postnatal signs of previous descriptions, especially the characteristic radiological abnormalities with ribs showing a ‘coat‐hanger’ configuration. Retrospective fetal ultrasound of our case allowed the identification of this pathognomonic feature prenatally, which makes it possible to consider pat UPD14 at routine prenatal sonography, in particular in combination with a small bell‐shaped thorax and polyhydramnios. Copyright © 2006 John Wiley & Sons, Ltd.
Prenatal diagnosis of Freeman–Sheldon syndrome and usefulness of an ultrasound fetal lip width normogram
Authors: Vimercati Antonella , Scioscia Marco , Burattini Maria Gabriella , Pontrelli Giovanni , Selvaggi Luigi E. 
Published: May 2006

AbstractObjectivesFreeman–Sheldon syndrome (FSS) is a rare genetic condition with facial and joint abnormalities. Here we report the first case of prenatal diagnosis in a fetus with negative familial history for this syndrome. A chart of the fetal mouth length was generated and its usefulness verified.MethodsA cross‐sectional study was carried out to derive standard charts for fetal lip lengths. The study population was made up of 371 fetuses between 15 and 38 weeks of gestation examined only once for this purpose. A statistical analysis previously recommended to derive normal ranges in fetal growth charts was employed.ResultsA 34‐year‐old woman was referred at 28 weeks of gestation for polyhydramnios and clubfeet. A detailed scan confirmed those findings and showed joint contractures of hands, a severe microstomia with a ‘whistling’ mouth, and an H‐shaped mark over the chin. FSS was suspected, though there was no family history for this genetic syndrome. After emergency delivery at 32 weeks, the syndrome was confirmed. The infant died two months later from pneumonia. Upon construction of a standard mouth length chart, it was found that the fetal lip width in this case of FSS was well below the 5th centile.ConclusionHere we present a standard chart for fetal lip width. We demonstrated its usefulness in cases with fetal face anomalies. Specific charts are fundamental for an objective assessment of the fetal parameters. Copyright © 2006 John Wiley & Sons, Ltd.
Antidepressant prevalence for youths: a multi‐national comparison
Authors: Zito Julie M. , Tobi Hilde , de Jong‐van den Berg Lolkje T.W. , Fegert Joerg M. , Safer Daniel J. , Janhsen Katrin , Hansen Dorte Gilså , Gardner James F. , Glaeske Gerd 
Published: May 2006

AbstractObjectiveTo compare antidepressant prevalence data in youths across three western European countries (Denmark, Germany, and the Netherlands) with US regional data in terms of age and gender and to show proportional subclass antidepressant (ATD) use.MethodA population‐based analysis of administrative claims data for the year 2000 was undertaken in 0 to 19‐year‐old enrollees who were part of the insured populations from four countries having a total of from 72,570 to 480,680 members.ResultsATD medication utilization in the US dataset (1.63%) exceeded that of three Western European countries (prevalence ranged from 0.11 to 0.54%) by at least 3‐fold. There were major variations in the use of subclasses: tricyclic antidepressants (TCAs) predominated in Germany while selective serotonin reuptake inhibitors (SSRIs) predominated in the US, Denmark and the Netherlands.ConclusionsCross‐national variations should be further explored to understand the factors related to these differences and how prevalence differences relate to effectiveness and safety. Community‐based cohorts should be followed to establish outcomes in the usual practice setting. Copyright © 2006 John Wiley & Sons, Ltd.
Adapting the sample size planning of a phase III trial based on phase II data
Authors: Wang Sue‐Jane , Hung H. M. James , O'Neill Robert T. 
Published: May 2006

AbstractTraditionally, in clinical development plan, phase II trials are relatively small and can be expected to result in a large degree of uncertainty in the estimates based on which Phase III trials are planned. Phase II trials are also to explore appropriate primary efficacy endpoint(s) or patient populations. When the biology of the disease and pathogenesis of disease progression are well understood, the phase II and phase III studies may be performed in the same patient population with the same primary endpoint, e.g. efficacy measured by HbA1c in non‐insulin dependent diabetes mellitus trials with treatment duration of at least three months. In the disease areas that molecular pathways are not well established or the clinical outcome endpoint may not be observed in a short‐term study, e.g. mortality in cancer or AIDS trials, the treatment effect may be postulated through use of intermediate surrogate endpoint in phase II trials. However, in many cases, we generally explore the appropriate clinical endpoint in the phase II trials. An important question is how much of the effect observed in the surrogate endpoint in the phase II study can be translated into the clinical effect in the phase III trial. Another question is how much of the uncertainty remains in phase III trials. In this work, we study the utility of adaptation by design (not by statistical test) in the sense of adapting the phase II information for planning the phase III trials. That is, we investigate the impact of using various phase II effect size estimates on the sample size planning for phase III trials. In general, if the point estimate of the phase II trial is used for planning, it is advisable to size the phase III trial by choosing a smaller alpha level or a higher power level. The adaptation via using the lower limit of the one standard deviation confidence interval from the phase II trial appears to be a reasonable choice since it balances well between the empirical power of the launched trials and the proportion of trials not launched if a threshold lower than the true effect size of phase III trial can be chosen for determining whether the phase III trial is to be launched. Published in 2006 by John Wiley & Sons, Ltd.
Methodological issues with adaptation of clinical trial design
Authors: James Hung H. M. , Wang Sue‐Jane , O'Neill Robert T. 
Published: May 2006

AbstractAdaptation of clinical trial design generates many issues that have not been resolved for practical applications, though statistical methodology has advanced greatly. This paper focuses on some methodological issues. In one type of adaptation such as sample size re‐estimation, only the postulated value of a parameter for planning the trial size may be altered. In another type, the originally intended hypothesis for testing may be modified using the internal data accumulated at an interim time of the trial, such as changing the primary endpoint and dropping a treatment arm. For sample size re‐estimation, we make a contrast between an adaptive test weighting the two‐stage test statistics with the statistical information given by the original design and the original sample mean test with a properly corrected critical value. We point out the difficulty in planning a confirmatory trial based on the crude information generated by exploratory trials. In regards to selecting a primary endpoint, we argue that the selection process that allows switching from one endpoint to the other with the internal data of the trial is not very likely to gain a power advantage over the simple process of selecting one from the two endpoints by testing them with an equal split of alpha (Bonferroni adjustment). For dropping a treatment arm, distributing the remaining sample size of the discontinued arm to other treatment arms can substantially improve the statistical power of identifying a superior treatment arm in the design. A common difficult methodological issue is that of how to select an adaptation rule in the trial planning stage. Pre‐specification of the adaptation rule is important for the practicality consideration. Changing the originally intended hypothesis for testing with the internal data generates great concerns to clinical trial researchers. Copyright © 2006 John Wiley & Sons, Ltd.
Application of an adaptive design to a randomized phase II selection trial in gastric cancer: a report of the study design
Authors: Morita Satoshi , Sakamoto Junichi 
Published: May 2006

AbstractRandomized phase II selection trials seek to provide unbiased comparisons for the selection of the most promising treatment arm for evaluation in a future phase III trial. In this paper, we present an application of an adaptive design to a randomized phase II selection trial comparing three experimental treatments with a control arm in patients with advanced gastric cancer. The trial design continuously monitors multiple patient outcomes to protect future patients from treatments with unacceptably high toxicity and/or unacceptably low efficacy. We use a Bayesian approach to monitor the trial and carry out simulations to investigate operating characteristics of the trial design. The simulation study also evaluates the sensitivity of the design to the prior distribution by considering two alternative priors. Copyright © 2006 John Wiley & Sons, Ltd.
Operational challenges in adaptive design implementation
Authors: Gallo Paul 
Published: May 2006

AbstractImplementation of adaptive clinical trial designs raises challenges with regard to the processes by which accruing trial data is analyzed, reviewed, and acted upon. In line with current monitoring conventions, it should be viewed that inappropriate knowledge of interim results can raise concerns regarding maintaining trial integrity and interpretability of results. Here we discuss issues related to these processes in adaptive trials, and point out distinctions versus other more familiar monitoring situations. One topic involves the composition of the group of individuals who will have access to interim results in order to recommend adaptations. We discuss operational models for data review by this group; one question addressed is whether in adaptive trials a role in this process for a representative of the study sponsor could at times be warranted, and might be justified if adequate protections are in place. Another issue involves whether adaptations made based upon interim data can convey to observers an amount of information about the results, which could rise to a level of concern. We consider whether different types of adaptations might be more or less problematic with regard to this issue, and recommend steps that might be considered to mitigate this concern. Copyright © 2006 John Wiley & Sons, Ltd.
Bayesian decision procedures for binary and continuous bivariate dose‐escalation studies
Authors: Zhou Yinghui , Whitehead John , Bonvini Elisa , Stevens John W. 
Published: May 2006

AbstractIn this paper, Bayesian decision procedures are developed for dose‐escalation studies based on binary measures of undesirable events and continuous measures of therapeutic benefit. The methods generalize earlier approaches where undesirable events and therapeutic benefit are both binary. A logistic regression model is used to model the binary responses, while a linear regression model is used to model the continuous responses. Prior distributions for the unknown model parameters are suggested. A gain function is discussed and an optional safety constraint is included. Copyright © 2006 John Wiley & Sons, Ltd.
Planning for an adaptive design: a case study in COPD
Authors: Jones B. , Atkinson G. , Ward J. , Tan E. , Kerbusch T. 
Published: May 2006

AbstractWe discuss the practical and clinical considerations encountered when planning a Phase IIa trial in chronic obstructive pulmonary disease (COPD). Various adaptive strategies for reducing the cost of the trial and the statistical implications of these are explored. Use of the EAST software to evaluate the properties of the study designs with one or more interim analyses for futility, efficacy or either is described. We emphasize the rationale for choosing between alternative designs and the relationship between the clinical and statistical considerations. Copyright © 2006 John Wiley & Sons, Ltd.
Characterization of high explosive particles using cluster secondary ion mass spectrometry
Authors: Gillen Greg , Mahoney Christine , Wight Scott , Lareau Richard 
Published: May 2006

AbstractThe use of secondary ion mass spectrometry (SIMS) for the detection and spatially resolved analysis of individual high explosive particles is described. A C carbon cluster primary ion beam was used in a commercial SIMS instrument to analyze samples of high explosives dispersed as particles on silicon substrates. In comparison with monatomic primary ion bombardment, the carbon cluster primary ion beam was found to greatly enhance characteristic secondary ion signals from the explosive compounds while causing minimal beam‐induced degradation. The resistance of these compounds to degradation under ion bombardment allows explosive particles to be analyzed under high primary ion dose bombardment (dynamic SIMS) conditions, facilitating the rapid acquisition of spatially resolved molecular information. The use of cluster SIMS combined with computer control of the sample stage position allows for the automated identification and counting of explosive particle distributions on silicon surfaces. This will be useful for characterizing the efficiency of transfer of particulates in trace explosive detection portal collectors and/or swipes utilized for ion mobility spectrometry applications. Published in 2006 by John Wiley & Sons, Ltd.
The fragmentation pathways of protonated Amiton in the gas phase: towards the structural characterisation of organophosphorus chemical warfare agents by electrospray ionisation tandem mass spectrometry
Authors: Ellis‐Steinborner Simon , Ramachandran Aravind , Blanksby Stephen J. 
Published: May 2006

AbstractAmiton (O,O‐diethyl‐S‐[2‐(diethylamino)ethyl] phosphorothiolate), otherwise known as VG, is listed in schedule 2 of the Chemical Weapons Convention (CWC) and has a structure closely related to VX (O‐ethyl‐S‐(2‐diisopropylamino)ethylmethylphosphonothiolate). Fragmentation of protonated VG in the gas phase was performed using electrospray ionisation ion trap mass spectrometry (ESI‐ITMS) and revealed several characteristic product ions. Quantum chemical calculations provide the most probable structures for these ions as well as the likely unimolecular mechanisms by which they are formed. The decomposition pathways predicted by computation are consistent with deuterium‐labeling studies. The combination of experimental and theoretical data suggests that the fragmentation pathways of VG and analogous organophosphorus nerve agents, such as VX and Russian VX, are predictable and thus ESI tandem mass spectrometry is a powerful tool for the verification of unknown compounds listed in the CWC. Copyright © 2006 Commonwealth of Australia. Published by John Wiley & Sons, Ltd.
Density functional theory meets statistical physics: from the atomistic to the mesoscopic properties of alloys
Authors: Müller Stefan 
Published: May 2006

AbstractToday, calculations based on density functional theory (DFT) allow us to study a number of metal alloy properties, as e.g. formation enthalpies, or electronic and elastic properties of intermetallic compounds. However, such so‐called (ab initio) calculations can only be applied as long as the alloy structure requires only small unit cells for the crystallographic description. This limitation can be overcome by combining DFT calculations with the so‐called Cluster Expansion (CE) methods and Monte‐Carlo (MC) simulations. The concept will be applied to study two characteristic type of interfaces, namely, the boundary between solid solution and precipitate as well as the alloy's surface. Copyright © 2006 John Wiley & Sons, Ltd.
XPS and ToF‐SIMS characterization of a Finemet surface: effect of cooling
Authors: Chenakin S. P. , Vasylyev M. A. , Kruse N. , Tolstogouzov A. B. 
Published: May 2006

AbstractThe surface composition of amorphous Finemet, Fe73Si15.8B7.2Cu1Nb3, was studied by X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). The as‐received sample in the original state and after Ar+ sputter‐cleaning was analyzed at room temperature as well as after cooling to − 155 °C. In the cooled state, the surface oxide layer composed of oxides of the alloy constituents was found to become enriched with elemental iron and depleted of elemental silicon, boron, oxygen and carbon as compared to the state at room temperature. Interaction of residual water vapor and hydrogen with the complex oxide layer occurring at low temperatures is believed to be responsible for the enhanced formation of surface hydroxides of the alloy constituents. The processes resulting in the observed redistribution of the elements on the surface of Finemet at low temperatures are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Seasonal patterns of fine root demography in a cool‐temperate deciduous forest in central Japan
Authors: Satomura Takami , Hashimoto Yasushi , Koizumi Hiroshi , Nakane Kaneyuki , Horikoshi Takao 
Published: May 2006

AbstractIn forest ecosystems, fine roots have a considerable role in carbon cycling. To investigate the seasonal pattern of fine root demography, we observed the fine root production and decomposition processes using a minirhizotron system in a Betula‐dominated forest with understory evergreen dwarf bamboo. The length density of fine roots decreased with increasing soil depth. The seasonal patterns of each fine root demographic parameter (length density of visible roots, rates of stand‐total fine root production and decomposition) were almost the same at different soil depths. The peak seasons of the fine root demographic parameters were observed in the order: stand‐total fine root production rate (late summer) > length density of the visible roots (early autumn) > stand‐total fine root decomposition rate (autumn, and a second small peak in spring). The fine root production rate was high in the latter part of the plant growing season. Fine root production peaked in late summer and remained high until the end of the tree defoliation season. The higher stand‐total fine root production rate in autumn suggests the effect of understory evergreen bamboo on the stand‐total fine root demography. The stand‐total fine root decomposition rate was high in late autumn. In the snow‐cover period, the rates of both fine root production and decomposition were low. The fine root demographic parameters appeared to show seasonal patterns. The fine root production rate had a clearer seasonality than the fine root decomposition rate. The seasonal pattern of stand‐total fine root production rate could be explained by both overstory and understory above‐ground productivities.
The effects of predation risk and current velocity stress on growth, condition and swimming energetics of Japanese minnow (Pseudorasbora parva)
Authors: Sunardi  , Asaeda Takashi , Manatunge Jagath , Fujino Takeshi 
Published: May 2006

AbstractA Japanese minnow, Pseudorasbora parva, was exposed simultaneously to multiple dangers in experimental tanks. The study aimed to quantify to what extent the risk of predation coinciding with an adverse environmental factor, high flow velocity, affects prey in terms of growth and energy expenditure. In this experiment, two measures of growth (i.e., body weight and length), condition, feeding, swimming cost and behavioral responses were analyzed. The results showed that in such an environment, prey showed lowered growth and were in a poorer condition. As the prey shifted to the shallow area with high flow velocity, the prey consumed a lower ration and incurred multiple costs for swimming locomotion that might reduce the allocation of energy to biomass and energy storage. Reduction in activity might decrease the cost of locomotion, but it did not have a considerable effect on overall swimming energy expenditure. In stream ecosystems, the high swimming energy expenditure appears to magnify the effects of predation risk by causing lowered growth and a poorer condition and, hence, fitness. The present study shows that high flow velocity is one of the environmental factors that determine the energetic responses of a potential prey to the presence of predators.