bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Use of Endoscopic Retrograde Cholangiopancreatography in the Diagnosis of Biliary Atresia in Infants Younger Than 100 Days
Authors: Shanmugam Naresh P , Harrison Phillip M , Devlin John , Peddu Praveen , Knisely AS , Davenport Mark , Hadžić Nedim 
Published: September 2009

ABSTRACTObjectives:We investigated the role and safety of endoscopic retrograde cholangiopancreatography (ERCP) in diagnosing biliary atresia (BA) in prolonged neonatal cholestasis, when standard workup was inconclusive.Patients and Methods:We reviewed notes of 48 cholestatic infants younger than 100 days undergoing ERCP from 1997 to 2007.Results:Amongst approximately 3300 infants evaluated for liver disease during the study, 224 (6.8%) were diagnosed with BA. Forty‐eight children underwent ERCP. Findings at liver biopsy (n = 47) included nonspecific cholestasis (n = 19, 40%), giant‐cell hepatitis (n = 12, 26%), “large bile duct obstruction” (n = 9, 19%) in the presence of pigmented stools, and mixed cholestatic/hepatitic features (n = 7, 15%). ERCP demonstrated a patent biliary tree in 20 infants (42%). BA was confirmed at exploratory laparotomy in all 3 infants (6%) in whom cannulation failed. The remaining 25 infants (52%) also proceeded to exploratory laparotomy, in which BA was confirmed in 22 (46%). Amongst the 20 children in whom ERCP ruled out BA, 8 (17%) had normal biliary anatomy, whilst 12 (25%) had an abnormal biliary tree, including 6 (12.5%) with neonatal sclerosing cholangitis. After ERCP none developed clinical pancreatitis or peritonitis.Conclusions:ERCP is a safe procedure for diagnosing BA even in the smallest infants with high positive and negative predictive values.
Folate related gene polymorphisms and susceptibility to develop childhood acute lymphoblastic leukaemia
Authors: Koppen Ilan J. N. , Hermans Frederik J. R. , Kaspers Gertjan J. L. 
Published: September 2009

SummaryAcute lymphoblastic leukaemia (ALL) is the most common paediatric cancer, accounting for nearly 30% of all paediatric cancers and 80% of childhood leukaemias. Polymorphisms in folate‐related genes may influence the susceptibility to childhood ALL. This review summarizes the results of 14 studies that focussed on the relationship between folate‐related gene polymorphisms and the susceptibility to ALL and that fulfilled certain quality criteria. The total group consisted of 729 children and 1821 adults or non age‐defined patients. The results of different studies sometimes contradict each other, for which there are several possible explanations. This includes an influence of the type of population studied, because there was a difference between Asian and European study results. Based on several studies, it is plausible that polymorphisms in the MTHFR gene, 677C>T and 1298A>C, are associated with a decreased susceptibility to childhood ALL in non‐Asian populations. Polymorphisms in other folate related genes (MTRR, MTR [MS], TYMS [TS], SLC19A1 [RFC1], NNMT, and SHMT1) are less clearly associated with susceptibility to ALL, and the number of included studies on this subject in this review is limited. Further investigations on the relevance of these polymorphisms need to be performed. In general, it is clear that susceptibility to (childhood) ALL is partly related to constitutional differences in folate gene polymorphisms.
Ecological responses to altered flow regimes: a literature review to inform the science and management of environmental flows
Authors: POFF N. LEROY , ZIMMERMAN JULIE K. H. 
Published: September 2009

Summary1. In an effort to develop quantitative relationships between various kinds of flow alteration and ecological responses, we reviewed 165 papers published over the last four decades, with a focus on more recent papers. Our aim was to determine if general relationships could be drawn from disparate case studies in the literature that might inform environmental flows science and management.2. For all 165 papers we characterised flow alteration in terms of magnitude, frequency, duration, timing and rate of change as reported by the individual studies. Ecological responses were characterised according to taxonomic identity (macroinvertebrates, fish, riparian vegetation) and type of response (abundance, diversity, demographic parameters). A ‘qualitative’ or narrative summary of the reported results strongly corroborated previous, less comprehensive, reviews by documenting strong and variable ecological responses to all types of flow alteration. Of the 165 papers, 152 (92%) reported decreased values for recorded ecological metrics in response to a variety of types of flow alteration, whereas 21 papers (13%) reported increased values.3. Fifty‐five papers had information suitable for quantitative analysis of ecological response to flow alteration. Seventy per cent of these papers reported on alteration in flow magnitude, yielding a total of 65 data points suitable for analysis. The quantitative analysis provided some insight into the relative sensitivities of different ecological groups to alteration in flow magnitudes, but robust statistical relationships were not supported. Macroinvertebrates showed mixed responses to changes in flow magnitude, with abundance and diversity both increasing and decreasing in response to elevated flows and to reduced flows. Fish abundance, diversity and demographic rates consistently declined in response to both elevated and reduced flow magnitude. Riparian vegetation metrics both increased and decreased in response to reduced peak flows, with increases reflecting mostly enhanced non‐woody vegetative cover or encroachment into the stream channel.4. Our analyses do not support the use of the existing global literature to develop general, transferable quantitative relationships between flow alteration and ecological response; however, they do support the inference that flow alteration is associated with ecological change and that the risk of ecological change increases with increasing magnitude of flow alteration.5. New sampling programs and analyses that target sites across well‐defined gradients of flow alteration are needed to quantify ecological response and develop robust and general flow alteration–ecological response relationships. Similarly, the collection of pre‐ and post‐alteration data for new water development programs would significantly add to our basic understanding of ecological responses to flow alteration.
Long‐term phytoplankton community changes in a deep subalpine lake: responses to nutrient availability and climatic fluctuations
Authors: SALMASO NICO 
Published: September 2009

Summary1. In natural lakes, modifications in the species composition and abundance of phytoplankton communities may ultimately be responses to changes in nutrient availability and climatic fluctuations. Phytoplankton and associated environmental factors were collected at monthly intervals from the beginning of the 1990s to 2007 in the large subalpine Lake Garda (zmax = 350 m, V = 49 × 109 m3). In this study period, the lake showed a slight and continuous increase of total phosphorus (TP) in the water column, up to concentrations of 18–20 μg P L−1. This increase represented the last stage of a long‐term process of enrichment documented since the 1970s, when concentrations of TP were below or around 10 μg P L−1.2. At the community level, annual phytoplankton cycles underwent a unidirectional and slow shift mainly due to changes in the species more affected by the nutrient enrichment of the lake. After a first and long period of dominance by conjugatophytes (Mougeotia) and diatoms (Fragilaria), phytoplankton biomass in recent years was sustained by cyanobacteria (Planktothrix). Other important modifications in the development of phytoplankton were superimposed on this pattern due to the effects of annual climate fluctuations principally mediated by the deep mixing events at spring overturn and, secondarily, by temperature and thermal stability of the water column during the growing season.3. Interannual variations in the stability and temperature of the water column appeared to influence the development of a few subdominant flagellates (dinophytes and cryptophytes). Nevertheless, the major impact of climate on phytoplankton was indirect, and mediated through the effects of winter climatic conditions on deep mixing dynamics. Winter climatic fluctuations proved to be a key element in a linked chain of causal factors including cooling of hypolimnetic waters, deep vertical mixing and epilimnetic nutrient replenishment. The process of fertilisation was measurable both for TP and dissolved inorganic nitrogen, although only the first had a large effect, reinforcing the seasonal growth of a few dominant groups. The degree of nutrient replenishment further increased the spring development of large diatoms and the increase of Planktothrix in summer and autumn.4. Currently, changes in nutrient concentrations have the greatest effect on the phytoplankton community, while direct effects due to the interannual variations in the thermal regime are of secondary importance compared with the indirect effects mediated through deep water mixing and spring fertilisation. Overall, the results demonstrate that the consequences of climatic fluctuations and climate warming on phytoplankton communities need to be studied at different levels of complexity and integration, from the direct effects of temperature and thermal regime, to the indirect effects mediated by the physiographic characteristics of water bodies.
Hybrid Ptr2‐like activators of archaeal transcription
Authors: Pritchett Matthew A. , Wilkinson Steven P. , Geiduschek E. Peter , Ouhammouch Mohamed 
Published: September 2009

Summary Methanocaldococcus jannaschii Ptr2, a member of the Lrp/AsnC family of bacterial DNA‐binding proteins, is an activator of its eukaryal‐type core transcription apparatus. In Lrp‐family proteins, an N‐terminal helix–turn–helix DNA‐binding and dimerizing domain is joined to a C‐terminal effector and multimerizing domain. A cysteine‐scanning surface mutagenesis shows that the C‐terminal domain of Ptr2 is responsible for transcriptional activation; two types of DNA binding‐positive but activation‐defective mutants are found: those unable to recruit the TBP and TFB initiation factors to the promoter, and those failing at a post‐recruitment step. Transcriptional activation through the C‐terminal Ptr2 effector domain is exploited in a screen of other Lrp effector domains for activation capability by constructing hybrid proteins with the N‐terminal DNA‐binding domain of Ptr2. Two hybrid proteins are effective activators: Ptr–H10, fusing the effector domain of Pyrococcus furiosus LrpA, and Ptr–H16, fusing the P. furiosus ORF1231 effector domain. Both new activators exhibit distinguishing characteristics: unlike octameric Ptr2, Ptr–H10 is a dimer; unlike Ptr2, the octameric Ptr–H16 poorly recruits TBP to the promoter, but more effectively co‐recruits TFB with TBP. In contrast, the effector domain of Ptr1, the M. jannaschii Ptr2 paralogue, yields only very weak activation.
Post‐transcriptional gene regulation of salinity and drought responses by plant microRNAs
Authors: COVARRUBIAS ALEJANDRA A. , REYES JOSÉ L. 
Published: September 2009

ABSTRACTIn the past few years, factors involved in abscisic acid signalling have been isolated and recognized as elements related to RNA metabolism, suggesting that post‐transcriptional regulation of gene expression is required for abiotic stress responses. Some of these factors can be linked to the biogenesis of microRNAs (miRNAs), small RNA molecules that are important regulators of gene expression at the posttranscriptional level by repressing mRNA expression. Here, we review the role of miRNAs in stress responses, highlighting recent advances in elucidating the role of individual miRNAs and efforts to identify stress‐responsive miRNAs at a genome‐wide level in different model plants. Complete understanding of miRNA action depends on the identification of its target transcripts, and recent developments in miRNA research indicate that they will be uncovered in the near future.
Metabolic‐dependent changes in plant cell redox power after ozone exposure
Authors: Dizengremel P. , Le Thiec D. , Hasenfratz‐Sauder M.‐P. , Vaultier M.‐N. , Bagard M. , Jolivet Y. 
Published: September 2009

AbstractThe tropospheric level of the phytotoxic air pollutant ozone has increased considerably during the last century, and is expected to continue to rise. Long‐term exposure of higher plants to low ozone concentrations affects biochemical processes prior to any visible symptoms of injury. The current critical level of ozone used to determine the threshold for damaging plants (biomass loss) is still based on the seasonal sum of the external concentration above 40 nl·l−1 (AOT40). Taking into account stomatal conductance and the internal capacity of leaf defences, a more relevant concept should be based upon the ‘effective ozone flux’, the balance between the stomatal flux and the intensity of cellular detoxification. The large decrease in the Rubisco/PEPc ratio reflects photosynthetic damage from ozone, and a large increase in activity of cytosolic PEPc, which allows increased malate production. Although the direct detoxification of ozone (and ROS produced from its decomposition) is carried out primarily by cell wall ascorbate, the existing level of this antioxidant is not sufficient to indicate the degree of cell sensitivity. In order to regenerate ascorbate, NAD(P)H is needed as the primary supplier of reducing power. It is hypothesised that increased activity of the catabolic pathways and associated shunts (glucose‐6‐phosphate dehydrogenase, NADP‐dependent glyceraldehyde‐3‐phosphate dehydrogenase, isocitrate dehydrogenase and malic enzyme) can provide sufficient NAD(P)H to maintain intracellular detoxification. Thus, measurement of the level of redox power would contribute to determination of the ‘effective ozone dose’, serving ultimately to improve the ozone risk index for higher plants.
Adefovir plus lamivudine are more effective than adefovir alone in lamivudine‐resistant HBeAg‐ chronic hepatitis B patients: A 4‐year study
Authors: Vassiliadis Themistoklis G , Giouleme Olga , Koumerkeridis Georgios , Koumaras Haralabos , Tziomalos Konstantinos , Patsiaoura Kalliopi , Grammatikos Nikolaos , Mpoumponaris Alexandros , Gkisakis Dimitrios , Theodoropoulos Konstantinos , Panderi Athanasia , Katsinelos Panagiotis , Eugenidis Nikolaos 
Published: September 2009

AbstractBackground and Aim:  Adefovir dipivoxil (ADV) is effective in lamivudine (LAM)‐resistant hepatitis B e antigen‐negative (HBeAg‐) chronic hepatitis B (CHB). However, it is unclear whether LAM treatment should be continued in these patients. We aimed to compare the long‐term efficacy of adding ADV to ongoing LAM treatment versus switching to ADV monotherapy in LAM‐resistant HBeAg‐ CHB.Methods:  Sixty LAM‐resistant patients with HBeAg‐ CHB were randomly assigned (3:1) to combination therapy (10 mg ADV once daily plus ongoing LAM at 100 mg once daily [n = 45]) or 10 mg ADV monotherapy once daily (n = 15). Virological and biochemical responses were defined as hepatitis B virus (HBV)–DNA <400 copies/mL and as normalization of alanine aminotransferase levels, respectively.Results:  The median follow‐up time was 53 months (range 20–60 months). A virological response was observed in 38/45 (84.4%) and 11/15 (73.3%) patients in the ADV/LAM and ADV monotherapy groups, respectively (P = 0.56). Biochemical response rates were higher in the ADV/LAM group than in the ADV monotherapy group (90.9% vs 57.1%, respectively; P = 0.01). In the ADV/LAM group, serum HBV–DNA remained undetectable in all patients who achieved a virological response (n = 38). In the ADV monotherapy group, virological breakthrough occurred in four of the 11 patients who achieved a virological response (36.4%; P < 0.001 vs the ADV/LAM group, log–rank test). In addition, two patients in each group who did not achieve a virological response eventually developed ADV resistance.Conclusions:  Adding ADV to LAM is more effective than switching to ADV monotherapy in LAM‐resistant patients with HBeAg‐ CHB.
Neural correlates of memory in depression measured by brain perfusion SPECT at rest
Authors: Azuma Hideki , Segawa Kazuhisa , Nakaaki Shutaro , Murata Yoshie , Kawakami Kazunori , Tohyama Junko , Iidaka Tetsuya , Shinagawa Yoshihiro , Nakano Yumi , Yamada Atsurou , Watanabe Norio , Hongo Jin , Akechi Tatsuo , Furukawa Toshi A. 
Published: September 2009

Aim:  Brain metabolism activated studies have indicated associations between memory and the anterior cingulate cortex and hippocampus in patients with depression. The aim of the present study was therefore to investigate memory function, measured as performance on the Wechsler Memory Scale–Revised (WMS‐R), and its relationship to brain perfusion using single‐photon emission computed tomography (SPECT) at rest in patients with depression.Methods:  The Hamilton Rating Scale for Depression (HAMD) and WMS‐R were measured for 17 patients with depression by an independent clinical evaluation team. Voxel‐based correlation analyses were performed with statistical parametric mapping at an extent threshold of 200 voxels. Associations were controlled for state and trait factors.Results:  WMS‐R measurements of verbal, visual, and general memory were inversely correlated with brain perfusion in the right anterior cingulate cortex, left premotor cortices, and both regions, respectively. The HAMD directly correlated with brain perfusion in the right anterior cingulate cortex.Conclusion:  Brain perfusion SPECT measurements of the anterior cingulate cortex at rest were associated with the severity of depression and immediate memory scores measured with the WMS‐R.
Desire to survive emotional pain related to self‐harm: A Norwegian hermeneutic study
Authors: Holm Anne Lise , Severinsson Elisabeth 
Published: September 2009

AbstractThe aim of this study was to explore and interpret women's desire to survive emotional pain related to self‐harm. Women who suffer from borderline personality disorder describe emotional pain as intense. Previous research indicates that self‐harm is a way of obtaining emotional relief and offers an escape from unwanted emotions, thoughts, and/or distressing situations. An explorative, interpretative design was employed. The data were collected by means of in‐depth interviews with a sample of women resident in Norway suffering from borderline personality disorder and were analyzed using a hermeneutic approach. The findings revealed one main theme, self‐sacrifice, and two other themes, self‐harm (a struggle to be relieved of responsibility) and a fear of intimacy versus intrusion. This study indicates that self‐sacrifice appears to imply a longing for reconnection with the self and others. To preserve their self‐image, the women require courage to survive the painful state of unworthiness.
Predatory senescence in ageing wolves
Authors: MacNulty Daniel R. , Smith Douglas W. , Vucetich John A. , Mech L. David , Stahler Daniel R. , Packer Craig 
Published: September 2009

Ecology Letters (2009) 12: 1347–1356AbstractIt is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long‐lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal data from repeated observations of individually‐known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to demonstrate that adult predatory performance declines with age and that an increasing ratio of senescent individuals in the wolf population depresses the rate of prey offtake. Because this ratio fluctuates independently of population size, predatory senescence may cause wolf populations of equal size but different age structure to have different impacts on prey populations. These findings suggest that predatory senescence is an important, though overlooked, factor affecting predator‐prey dynamics.
Modelling the Joint Impact of the CEO and the TMT on Organizational Ambidexterity
Authors: Cao Qing , Simsek Zeki , Zhang Hongping 
Published: September 2009

abstractWhile researchers continue to debate how firms might attain ambidexterity, recent research demonstrates that top management teams (TMTs) play a pivotal role. We enrich this line of inquiry by specifying a model that blends the effect of the CEO and the TMT on ambidexterity. Specifically, given the importance of networking and building social capital to the access of timely, valuable, and diverse information, we first envision that the CEO's network extensiveness will positively impact ambidexterity. Next, we argue that this impact will be bolstered when the CEO–TMT interactional interface, including communication richness, functional complementarity, and power decentralization, enable the entire TMT to process disparate information demands essential to attaining ambidexterity. We test and find general support for our model using multi‐source survey data from 122 small‐ to medium‐sized enterprises (SMEs).
A Framework for Interactive Hypertexture Modelling
Authors: Gilet G. , Dischler J.M. 
Published: September 2009

Abstract Hypertexturing can be a powerful way of adding rich geometric details to surfaces at low memory cost by using a procedural three‐dimensional (3D) space distortion. However, this special kind of texturing technique still raises a major problem: the efficient control of the visual result. In this paper, we introduce a framework for interactive hypertexture modelling. This framework is based on two contributions. First, we propose a reformulation of the density modulation function. Our density modulation is based on the notion of shape transfer function. This function, which can be easily edited by users, allows us to control in an intuitive way the visual appearance of the geometric details resulting from the space distortion. Second, we propose to use a hybrid surface and volume‐point‐based representation in order to be able to dynamically hypertexture arbitrary objects at interactive frame rates. The rendering consists in a combined splat‐ and raycasting‐based direct volume rendering technique. The splats are used to model the volumetric object while raycasting allows us to add the details. An experimental study on users shows that our approach improves the design of hypertextures and yet preserves their procedural nature.
Robust and Optimized Algorithms for the Point‐in‐Polygon Inclusion Test without Pre‐processing
Authors: Jiménez J. J. , Feito F. R. , Segura R. J. 
Published: September 2009

Abstract In this work we present new point inclusion algorithms for non‐convex polygons. These algorithms do not perform any pre‐processing or any type of decomposition nor features classification, which makes them especially suitable for deformable or moving polygons. The algorithms are more accurate and robust than others in the sense that they consider the inclusion of the point in the vertices and edges of the polygon, and deal with the special cases correctly. In order to perform this inclusion test efficiently, they use the sign of the barycentric coordinates of the test point with regard to the triangles formed by the edges and an origin that depends on the test point. This set of triangles, which is a special simplicial covering of the polygon, is constructed after a transformation of the polygon that simplifies the calculations involved in the inclusion test. Then, an appropriate ordering of the rejection tests allows us to optimize this method. Our algorithms have been tested for robustness and compared with ray‐crossing methods, showing a significant improvement.