bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serum thymus and activation regulated chemokine levels post-lung transplantation as a predictor for the bronchiolitis obliterans syndrome
Authors: Paantjens A W M , Kwakkel-van Erp J M , van Ginkel W G J , van Kessel D A , van den Bosch J M M , van de Graaf E A , Otten H G 
Published: October 2008

Summary
The main reason for mortality after lung transplantation is the bronchiolitis obliterans syndrome (BOS), which represents chronic rejection. As soluble CD30, which is produced mainly by activated T helper 2 (Th2) cells, was shown to be related to development of BOS, we aimed to investigate the relation between development of BOS and Th2 chemoattractant thymus and activation regulated chemokine (TARC/CCL17). In 54 patients we measured serum TARC levels prior to transplantation by enzyme-linked immunosorbent assay, and in 44 of these patients sera were analysed at months 1, 2 and 3 after lung transplantation. In addition, longitudinal measurements were performed in sera from eight healthy controls and 14 patients, the latter taken over a period of 2 years post-transplantation from seven patients developing BOS plus seven clinically matched BOS-free patients. Median serum TARC levels post-transplantation of patients who developed BOS were significantly lower than those of the matched BOS-free patients (P = 0·05). A receiver operating characteristics analysis (area under the curve 0·77), together with a Kaplan–Meyer analysis, showed that serum TARC levels below 325 pg/ml in the first month post-transplantation can predict development of BOS post-transplantation (P = 0·001). In contrast, pretransplant serum TARC levels were not significantly different between patients developing BOS, BOS-free patients or healthy controls. In conclusion, pretransplantation serum TARC levels do not predict the development of BOS post-transplantation, but measurement of the serum TARC levels in the first month directly after transplantation can provide us with a tool to identify the group at risk of developing BOS.
Impaired dendritic cell maturation and cytokine production in patients with chronic mucocutanous candidiasis with or without APECED
Authors: Ryan K R , Hong M , Arkwright P D , Gennery A R , Costigan C , Dominguez M , Denning D , McConnell V , Cant A J , Abinun M , Spickett G P , Lilic D 
Published: October 2008

Summary
Patients with chronic mucocutaneous candidiasis (CMC) suffer persistent infections with the yeast Candida. CMC includes patients with autoimmune regulator (AIRE) gene mutations who have autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED), and patients without known mutations. CMC patients have dysregulated cytokine production, and dendritic cells (DCs), as central orchestrators, may underlie pathogenic disease mechanisms. In 29 patients with CMC (13 with APECED) and controls, we generated monocyte-derived DCs, stimulated them with Candida albicans, Toll-like receptor-2/6 ligand and lipopolysaccharide to assess cytokine production [interleukin (IL)-12p70, IL-23, interferon (IFN)-γ, IL-2, tumour necrosis factor (TNF)-α, IL-6, transforming growth factor-β, IL-10, IL-5, IL-13] and cell-surface maturation marker expression (CD83, CD86, human leucocyte antigen D-related). In both APECED and non-APECED CMC patients, we demonstrate impairment of DC function as evidenced by altered cytokine expression profiles and DC maturation/activation: (1) both groups over-produce IL-2, IFN-γ, TNF-α and IL-13 and demonstrate impaired DC maturation. (2) Only non-APECED patients showed markedly decreased Candida-stimulated production of IL-23 and markedly increased production of IL-6, suggesting impairment of the IL-6/IL-23/T helper type 17 axis. (3) In contrast, only APECED patients showed DC hyperactivation, which may underlie altered T cell responsiveness, autoimmunity and impaired response to Candida. We demonstrate different pathogenic mechanisms on the same immune response pathway underlying increased susceptibility to Candida infection in these patients.
Initial growth deceleration during GnRH analogue therapy for precocious puberty
Authors: Mouat Frances , Hofman Paul L. , Jefferies Craig , Gunn Alistair Jan , Cutfield Wayne S. 
Published: October 2008

SummaryObjectives  To compare the efficacy of goserelin and leuprolide on initial deceleration of growth and weight gain during the first 12 months of GnRH analogue treatment for precocious puberty.Design  Retrospective cohort analysis.Patients  Forty children with precocious puberty treated with either goserelin or leuprolide (33 females, mean age 7·3 and 7·7 years, respectively, at the start of treatment).Measurements  The primary outcomes were baseline‐to‐6‐months and 6‐months‐to‐12‐months change in height standard deviation score (SDS) and body mass index (BMI). Relative tall stature was calculated as the difference between height SDS and mid‐parental height (MPH) SDS at baseline.Results  Goserelin and leuprolide were associated with similar suppression of serum LH during the first 12 months of treatment (P = 0·62). Greater relative tall stature was strongly associated with more advanced bone age, greater BMI SDS and with greater reduction in height SDS in the first 6 months. Adjusted for relative tall stature, goserelin therapy was associated with significantly greater suppression of growth than leuprolide (P = 0·025) in the first 6 months of treatment, with no subsequent change in the second 6 months. A similar, significant increase in BMI was seen with both analogues.Conclusions  Both GnRH analogues were associated with effective biochemical suppression of puberty; however, goserelin was more effective at reducing linear growth during the first 6 months. Relative tall stature was a major determinant of the initial response to treatment.
Breastfeeding and maternal and infant iodine nutrition
Authors: Azizi Fereidoun , Smyth Peter 
Published: October 2008

SummaryObjective  The aim of this review is to explore information available regarding iodine secretion in milk, both mothers and infants iodine nutrition during breastfeeding and to make recommendations for appropriate iodine supplementation during lactation.Design  MEDLINE was queried for studies between 1960 and 2007 that included lactation and breastfeeding with iodine and iodine deficiency. Studies were selected if they studied (i) Secretion of iodine in breast milk; (ii) breastfeeding and iodine nutrition; (iii) factors affecting maternal iodine metabolism and (iv) recommendations for iodine supplementation during breastfeeding.Results  Thirty‐six articles met the selection criteria. The iodine content of breast milk varies with dietary iodine intake, being lowest in areas of iodine deficiency with high prevalence of goitre. Milk iodine levels are correspondingly higher when programs of iodine prophylaxis such as salt iodization or administration of iodized oil have been introduced. The small iodine pool of the neonatal thyroid turns over very rapidly and is highly sensitive to variations in dietary iodine intake. Expression of the sodium iodide symporter is up‐regulated in the lactating mammary gland which results in preferential uptake of iodide. In areas of iodine sufficiency breast milk iodine concentration should be in the range of 100–150 µg/dl. Studies from France, Germany, Belgium, Sweden, Spain, Italy, Denmark, Thailand and Zaire have shown breast milk concentrations of < 100 µg/l. Adequate levels of iodine in breast milk have been reported from Iran, China, USA and some parts of Europe.Conclusions  Adequate concentration of iodine in breast milk is essential to provide for optimal neonatal thyroid hormone stores and to prevent impaired neurological development in breast‐fed neonates. In many countries of the world, low iodine content of the breast milk indicates less than optimum maternal and infant iodine nutrition. The current WHO/ICCIDD/UNICEF recommendation for daily iodine intake (250 µg for lactating mothers) has been selected to ensure that iodine deficiency dose not occur in the postpartum period and that the iodine content of the milk is sufficient for the infant's iodine requirement.
Angiotensin inhibition stimulates PPARγ and the release of visfatin
Authors: Storka A. , Vojtassakova E. , Mueller M. , Kapiotis S. , Haider D. G. , Jungbauer A. , Wolzt M. 
Published: October 2008

ABSTRACTBackground  Angiotensin converting enzyme inhibitors (ACE‐I) and angiotensin receptor blockers (ARB) exhibit beneficial antidiabetic effects in patients with type 2 diabetes independent of their blood pressure‐lowering effects. Some antidiabetic properties of ARB and ACE‐I might by exerted by activation of peroxisome proliferator‐activated receptor gamma (PPARγ). However, it is not clear whether this action is drug specific.Materials and methods  The binding affinity of telmisartan, valsartan, lisinopril, rosiglitazone and angiotensin II to PPARγ was assessed in a cell‐free assay system. PPARγ signalling was studied in isolated skeletal muscle cells using Western blot analysis of phosphorylated protein kinase B (pAKT) and phosphorylated insulin like growth factor‐1 receptor (pILGF‐1R). Further, the ability of the drugs under study to stimulate the release of the adipocytokine visfatin was investigated in isolated human adipocytes, skeletal muscle cells, and umbilical vein endothelial cells (HUVEC).Results  The binding affinity to PPARγ was highest for telmisartan with a half‐maximal effective concentration of 463 nM, followed by lisinopril (2·9 µM) and valsartan (6·2 µM). In skeletal muscle cells phosphorylation of ILGF‐1R was 2‐fold increased after incubation with telmisartan or valsartan and 1·7‐fold with lisinopril. pAKT expression was enhanced after incubation with telmisartan, valsartan and with lisinopril. The release of visfatin from adipocytes was 1·6‐fold increased after treatment with lisinopril and about 2·0‐fold increased with telmisartan and valsartan. Similar results were obtained in skeletal muscle cells and HUVEC.Conclusions  Our data confirm agonism of telmisartan, valsartan and lisinopril on PPARγ. Pharmacokinetic differences may explain different potencies of PPARγ stimulation by drugs acting on the renin‐angiotensin system in clinical settings.
Contrasting patterns of population structure in the montane caddisflies Hydropsyche tenuis and Drusus discolor in the Central European highlands
Authors: LEHRIAN STEPHANIE , PAULS STEFFEN U. , HAASE PETER 
Published: October 2008

Summary1. In this study, we compared mitochondrial sequence data (cytochrome oxidase I) to infer the population structure of the two montane caddisflies Hydropsyche tenuis and Drusus discolor. The two species are contrasting examples of montane aquatic insects with insular distributions: D. discolor is restricted to altitudes above 600 m, H. tenuis is limited to the same mountain ranges in Central Europe but inhabits lower altitudes.2. In particular, we ask whether these two species with similar regional distributions show similar patterns of population structure and haplotype diversity, and whether any differences can be attributed to population history and/or autecology.3. To determine the population structure of both species, we applied conventional population genetics analyses to mitochondrial sequence data. We collected and sampled 121 specimens of H. tenuis from 29 sites in 10 different regions of the Central European highlands and 138 individuals of D. discolor from 40 sites in 11 different regions.4. Nine unique haplotypes were identified for H. tenuis and 34 for D. discolor. There were eight variable positions in H. tenuis and 41 in D. discolor. The maximum difference between haplotypes was 0.8% (4 bp) for H. tenuis and 4.2% (21 bp) for D. discolor. We observed haplotype overlap between geographic regions for both species. Analysis of molecular variance showed that two‐thirds of the total variance in H. tenuis was found among regions while in D. discolor, a larger portion of variance was found within regions and populations due to a higher number of haplotypes observed within regions. Mantel test showed a significant relationship between genetic and geographic distance in D. discolor, but no significant relationship in H. tenuis.5. Our analyses show that, despite their very similar overall distribution pattern in Europe, the two species exhibit distinct population structures, which may reflect differences in phylogeographic history, dispersal capabilities, habitat specifity or within‐region geographic occurrence.
Quantitative imaging of the Permo‐Mesozoic complex and its basement by frequency domain waveform tomography of wide‐aperture seismic data from the Polish Basin
Authors: Malinowski Michal , Operto Stéphane 
Published: October 2008

ABSTRACTIn this study we present the workflow and results of 2D frequency domain waveform tomography applied to the global‐offset seismic data acquired in central Poland along a 50‐km long profile during the GRUNDY 2003 experiment. The waveform tomography method allows full exploitation of the wide‐aperture content of these data and produces in a semi‐automatic way both the detailed P‐wave velocity model and the structural image (i.e., perturbations in respect to the starting model). Thirteen frequencies ranging from 4 to 16 Hz were inverted sequentially, gradually introducing higher wavenumbers and more details into the velocity models. Although the data were characterised by relatively large shot spacings (1.5 km), we obtained clear images both of the Mesozoic and Permian sedimentary cover. Velocity patterns indicated facies changes within the Jurassic and Zechstein strata. A high velocity layer (ca. 5500 m/s) was found near the base of Triassic (Scythian), which made the imaging of a deeper layer difficult. Nevertheless, we were able to delineate the base of the Permian (i.e., base of the Rotliegend), which was not possible to derive from conventional common‐depth‐point processing, as well as some deeper events, attributed to the Carboniferous. The sub‐Permian events formed a syn‐form which favoured our previous interpretation of a depression filled with Upper Carboniferous molasse. The validity of the waveform tomography‐derived model was confirmed by well‐log data. Forward ray‐tracing modelling and synthetic seismograms calculations provided another justification for the key structures present in the waveform tomography model.
Investigation into the use of 2D elastic waveform inversion from look‐ahead walk‐away VSP surveys
Authors: Roberts Mark A. , Singh Satish , Hornby Brian E. 
Published: October 2008

ABSTRACTPore pressure in sediments beneath salt in the Gulf of Mexico varies widely creating a potentially dangerous and difficult drilling challenge. Estimating elastic parameters of sediments beneath salt is key to the prediction of pore pressure and reducing the drilling risk in exiting the base of the salt. In this paper we investigate the ability of 2D waveform inversion to recover the elastic parameters in the sedimentary layer beneath the salt from a walk‐away VSP (vertical seismic profile) carried out with the receivers in the salt, with the objective of estimating pore pressure at the base of the salt (to be estimated using traditional methods). We propose an effective method for performing the inversion and apply this method to a blind test of a large and realistic synthetic dataset. To facilitate the design of a VSP survey suitable to this type of inversion we also present an analysis into the effects of the receiver array receiver spacing. It is shown that the resulting velocity estimates are sufficiently accurate to predict the pore pressure within the limits required for drilling.
Elastic full waveform inversion of multi‐component OBC seismic data
Authors: Sears T.J. , Singh S.C. , Barton P.J. 
Published: October 2008

ABSTRACTElastic full waveform inversion of seismic reflection data represents a data‐driven form of analysis leading to quantification of sub‐surface parameters in depth. In previous studies attention has been given to P‐wave data recorded in the marine environment, using either acoustic or elastic inversion schemes. In this paper we exploit both P‐waves and mode‐converted S‐waves in the marine environment in the inversion for both P‐ and S‐wave velocities by using wide‐angle, multi‐component, ocean‐bottom cable seismic data. An elastic waveform inversion scheme operating in the time domain was used, allowing accurate modelling of the full wavefield, including the elastic amplitude variation with offset response of reflected arrivals and mode‐converted events. A series of one‐ and two‐dimensional synthetic examples are presented, demonstrating the ability to invert for and thereby to quantify both P‐ and S‐wave velocities for different velocity models. In particular, for more realistic low velocity models, including a typically soft seabed, an effective strategy for inversion is proposed to exploit both P‐ and mode‐converted PS‐waves. Whilst P‐wave events are exploited for inversion for P‐wave velocity, examples show the contribution of both P‐ and PS‐waves to the successful recovery of S‐wave velocity.
Feasibility study for an anisotropic full waveform inversion of cross‐well seismic data
Authors: Barnes Christophe , Charara Marwan , Tsuchiya Terumitsu 
Published: October 2008

ABSTRACTAnisotropy is often observed due to the thin layering or aligned micro‐structures, like small fractures. At the scale of cross‐well tomography, the anisotropic effects cannot be neglected. In this paper, we propose a method of full‐wave inversion for transversely isotropic media and we test its robustness against structured noisy data.Optimization inversion techniques based on a least‐square formalism are used. In this framework, analytical expressions of the misfit function gradient, based on the adjoint technique in the time domain, allow one to solve the inverse problem with a high number of parameters and for a completely heterogeneous medium.The wave propagation equation for transversely isotropic media with vertical symmetry axis is solved using the finite difference method on the cylindrical system of coordinates. This system allows one to model the 3D propagation in a 2D medium with a revolution symmetry. In case of approximately horizontal layering, this approximation is sufficient.The full‐wave inversion method is applied to a crosswell synthetic 2‐component (radial and vertical) dataset generated using a 2D model with three different anisotropic regions. Complex noise has been added to these synthetic observed data. This noise is Gaussian and has the same amplitude f−k spectrum as the data. Part of the noise is localized as a coda of arrivals, the other part is not localized. Five parameter fields are estimated, (vertical) P‐wave velocity, (vertical) S‐wave velocity, volumetric mass and the Thomsen anisotropic parameters epsilon and delta. Horizontal exponential correlations have been used. The results show that the full‐wave inversion of cross‐well data is relatively robust for high‐level noise even for second‐order parameters such as Thomsen epsilon and delta anisotropic parameters.
Velocity analysis based on data correlation
Authors: Van Leeuwen T. , Mulder W.A. 
Published: October 2008

ABSTRACTSeveral methods exist to automatically obtain a velocity model from seismic data via optimization. Migration velocity analysis relies on an imaging condition and seeks the velocity model that optimally focuses the migrated image. This approach has been proven to be very successful. However, most migration methods use simplified physics to make them computationally feasible and herein lies the restriction of migration velocity analysis. Waveform inversion methods use the full wave equation to model the observed data and more complicated physics can be incorporated. Unfortunately, due to the band‐limited nature of the data, the resulting inverse problem is highly nonlinear. Simply fitting the data in a least‐squares sense by using a gradient‐based optimization method is sometimes problematic. In this paper, we propose a novel method that measures the amount of focusing in the data domain rather than the image domain. As a first test of the method, we include some examples for 1D velocity models and the convolutional model.
Exploring some issues in acoustic full waveform inversion
Authors: Mulder W.A. , Plessix R.‐E. 
Published: October 2008

ABSTRACTThe least‐squares error measures the difference between observed and modelled seismic data. Because it suffers from local minima, a good initial velocity model is required to avoid convergence to the wrong model when using a gradient‐based minimization method. If a data set mainly contains reflection events, it is difficult to update the velocity model with the least‐squares error because the minimization method easily ends up in the nearest local minimum without ever reaching the global minimum.Several authors observed that the model could be updated by diving waves, requiring a wide‐angle or large‐offset data set. This full waveform tomography is limited to a maximum depth. Here, we use a linear velocity model to obtain estimates for the maximum depth. In addition, we investigate how frequencies should be selected if the seismic data are modelled in the frequency domain. In the presence of noise, the condition to avoid local minima requires more frequencies than needed for sufficient spectral coverage.We also considered acoustic inversion of a synthetic marine data set created by an elastic time‐domain finite‐difference code. This allowed us to validate the estimates made for the linear velocity model. The acoustic approximation leads to a number of problems when using long‐offset data. Nevertheless, we obtained reasonable results. The use of a variable density in the acoustic inversion helped to match the data at the expense of accuracy in the inversion result for the density.
Two‐dimensional waveform inversion of multi‐component data in acoustic‐elastic coupled media
Authors: Choi Yunseok , Min Dong‐Joo , Shin Changsoo 
Published: October 2008

ABSTRACTIn order to account for the effects of elastic wave propagation in marine seismic data, we develop a waveform inversion algorithm for acoustic‐elastic media based on a frequency‐domain finite‐element modelling technique. In our algorithm we minimize residuals using the conjugate gradient method, which back‐propagates the errors using reverse time migration without directly computing the partial derivative wavefields. Unlike a purely acoustic or purely elastic inversion algorithm, the Green's function matrix for our acoustic‐elastic algorithm is asymmetric. We are nonetheless able to achieve computational efficiency using modern numerical methods. Numerical examples show that our coupled inversion algorithm produces better velocity models than a purely acoustic inversion algorithm in a wide variety of cases, including both single‐ and multi‐component data and low‐cut filtered data. We also show that our algorithm performs at least equally well on real field data gathered in the Korean continental shelf.