bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impacts of climate on prey abundance account for fluctuations in a population of a northern wader at the southern edge of its range
Authors: PEARCE‐HIGGINS JAMES W. , DENNIS PETER , WHITTINGHAM MARK J. , YALDEN DEREK W. 
Published: February 2009

AbstractUnderstanding the mechanisms by which climate change will affect animal populations is vital for adaptive management. Many studies have described changes in the timing of biological events, which can produce phenological mismatch. Direct effects on prey abundance might also be important, but have rarely been studied. We examine the likely importance of variation in prey abundance in driving the demographics of a European golden plover (Pluvialis apricaria) population at its southern range margin. Previous studies have correlated plover productivity with the abundance of their adult cranefly (Tipulidae) prey, and modelled the phenology of both plover breeding and cranefly emergence in relation to temperature. Our analyses demonstrate that abundance of adult craneflies is correlated with August temperature in the previous year. Correspondingly, changes in the golden plover population are negatively correlated with August temperature 2 years earlier. Predictions of annual productivity, based on temperature‐mediated reductions in prey abundance, closely match observed trends. Modelled variation in annual productivity for a future scenario of increasing August temperatures predicts a significant risk of extinction of the golden plover population over the next 100 years, depending upon the magnitude of warming. Direct effects of climate warming upon cranefly populations may therefore cause northward range contractions of golden plovers, as predicted by climate envelope modelling. Craneflies are an important food source for many northern and upland birds, and our results are likely to have wide relevance to these other species. Research into the potential for habitat management to improve the resilience of cranefly populations to high temperature should be an urgent priority.
Carbon dynamics in topsoil and in subsoil may be controlled by different regulatory mechanisms
Authors: SALOMÉ CLÉMENCE , NUNAN NAOISE , POUTEAU VALÉRIE , LERCH THOMAS Z. , CHENU CLAIRE 
Published: February 2009

AbstractIt is estimated that in excess of 50% of the soil carbon stock is found in the subsoil (below 20–30 cm). Despite this very few studies have paid attention to the subsoil. Although surface and subsurface horizons differ in pedological, environmental and physicochemical features, which are all likely to affect the mechanisms and biological actors involved, models of carbon dynamics tend to assume that the underlying processes are identical in all horizons, but with lower gross fluxes in the subsurface. The aim of this study was to test this assumption by analysing factors governing organic matter decomposition in topsoil (from depths of 5–10 cm) and subsoil (from depths of 80–100 cm). To this end, we established incubations that lasted 51 days, in which factors that were thought to control organic matter mineralization were altered: oxygen concentration, soil structure and the energetic and nutritional status. At the end of the incubation period, the microbial biomass was measured and the community level physiological profiles established. The mineralization per unit organic carbon proved to be as important in the subsoil as it was in surface samples, in spite of lower carbon contents and different catabolic profiles. Differences in the treatment effects indicated that the controls on C dynamics were different in topsoil and subsoil: disrupting the structure of the subsoil caused a 75% increase in mineralization while the surface samples remained unaffected. On the other hand, a significant priming affect was found in the topsoil but not in the subsoil samples. Spatial heterogeneity in carbon content, respiration and microbial communities was greater in subsoil than in topsoil at the field scale. These data suggest greater attention should be paid to the subsoil if global C dynamics is to be fully understood.
Synergistic effects of climate change and local stressors: CO2 and nutrient‐driven change in subtidal rocky habitats
Authors: RUSSELL BAYDEN D. , THOMPSON JO‐ANNE I. , FALKENBERG LAURA J. , CONNELL SEAN D. 
Published: February 2009

AbstractClimate‐driven change represents the cumulative effect of global through local‐scale conditions, and understanding their manifestation at local scales can empower local management. Change in the dominance of habitats is often the product of local nutrient pollution that occurs at relatively local scales (i.e. catchment scale), a critical scale of management at which global impacts will manifest. We tested whether forecasted global‐scale change [elevated carbon dioxide (CO2) and subsequent ocean acidification] and local stressors (elevated nutrients) can combine to accelerate the expansion of filamentous turfs at the expense of calcifying algae (kelp understorey). Our results not only support this model of future change, but also highlight the synergistic effects of future CO2 and nutrient concentrations on the abundance of turfs. These results suggest that global and local stressors need to be assessed in meaningful combinations so that the anticipated effects of climate change do not create the false impression that, however complex, climate change will produce smaller effects than reality. These findings empower local managers because they show that policies of reducing local stressors (e.g. nutrient pollution) can reduce the effects of global stressors not under their governance (e.g. ocean acidification). The connection between research and government policy provides an example whereby knowledge (and decision making) across local through global scales provides solutions to some of the most vexing challenges for attaining social goals of sustainability, biological conservation and economic development.
Designing for inquiry‐based learning with the Learning Activity Management System
Authors: Levy P. , Aiyegbayo O. , Little S. 
Published: February 2009

AbstractThis paper explores the relationship between practitioners' pedagogical purposes, values and practices in designing for inquiry‐based learning in higher education, and the affordances of the Learning Activity Management System (LAMS) as a tool for creating learning designs in this context. Using a qualitative research methodology, variation was identified in participants' conceptions of inquiry‐based learning pedagogy and in their approaches to inquiry‐based learning design. LAMS was found to offer design affordances that are compatible with more strongly teacher‐led conceptions of, and approaches to, inquiry‐based learning pedagogy. The paper draws some implications for the further development and use of design tools for inquiry‐based learning. The authors suggest that, in addition to tools created for teachers, there may be a valuable role for tools that explicitly support students as designers of their own inquiry processes and activities.
Analysis of cytosolic and plastidic serine acetyltransferase mutants and subcellular metabolite distributions suggests interplay of the cellular compartments for cysteine biosynthesis in Arabidopsis
Authors: KRUEGER STEPHAN , NIEHL ANNETTE , LOPEZ MARTIN M. CARMEN , STEINHAUSER DIRK , DONATH ANDREA , HILDEBRANDT TATJANA , ROMERO LUIS C. , HOEFGEN RAINER , GOTOR CECILIA , HESSE HOLGER 
Published: February 2009

ABSTRACTIn plants, the enzymes for cysteine synthesis serine acetyltransferase (SAT) and O‐acetylserine‐(thiol)‐lyase (OASTL) are present in the cytosol, plastids and mitochondria. However, it is still not clearly resolved to what extent the different compartments are involved in cysteine biosynthesis and how compartmentation influences the regulation of this biosynthetic pathway. To address these questions, we analysed Arabidopsis thaliana T‐DNA insertion mutants for cytosolic and plastidic SAT isoforms. In addition, the subcellular distribution of enzyme activities and metabolite concentrations implicated in cysteine and glutathione biosynthesis were revealed by non‐aqueous fractionation (NAF). We demonstrate that cytosolic SERAT1.1 and plastidic SERAT2.1 do not contribute to cysteine biosynthesis to a major extent, but may function to overcome transport limitations of O‐acetylserine (OAS) from mitochondria. Substantiated by predominantly cytosolic cysteine pools, considerable amounts of sulphide and presence of OAS in the cytosol, our results suggest that the cytosol is the principal site for cysteine biosynthesis. Subcellular metabolite analysis further indicated efficient transport of cysteine, γ‐glutamylcysteine and glutathione between the compartments. With respect to regulation of cysteine biosynthesis, estimation of subcellular OAS and sulphide concentrations established that OAS is limiting for cysteine biosynthesis and that SAT is mainly present bound in the cysteine–synthase complex.
Placing Regulatory T cells into Global Theories of Immunity: an Analysis of Cohn’s Challenge to Integrity (Dembic)
Authors: Anderson C. C. 
Published: February 2009

AbstractIn broadening the integrity model, Zlatko Dembic provided one of the few plausible explanations for the existence of regulatory T cells that has been postulated to date and at the same time highlighted deficiencies of the associative antigen recognition model. In defending the virtues of associative antigen recognition, Melvin Cohn has challenged the integrity model and the concept that regulatory T cells have a role in defining the specificity of immune responses. The critique of Cohn’s analysis I present here suggests that a greater consideration of quantitative evolutionary constraints removes most of the challenges to integrity.
Chemokine responsiveness of CD4+ CD25+ regulatory and CD4+ CD25− T cells from atopic and nonatopic donors
Authors: Ahern D. , Lloyd C. M. , Robinson D. S. 
Published: February 2009

Background:  Allergic inflammation is associated with Th2‐type T cells, which can be suppressed by CD4+ CD25+ regulatory T cells (Tregs). Both express chemokine receptors (CCR) 4 and CCR8, but the dynamics of expression and effect of atopic status are unknown.Objective:  To examine the expression of chemokine receptors by CD4+ CD25+ and CD4+ CD25− T cells from atopic and nonatopic donors, and document response to allergen stimulation in vitro.Methods:  Chemokine receptor expression was examined by flow cytometry and quantitative PCR of CD4+ CD25hi and CD4+ CD25− T cells from atopics and nonatopics. Responsiveness to chemokines was by actin polymerization. Dynamics of chemokine receptor expression in 6‐day allergen‐stimulated cultures was analysed by carboxyfluoroscein succinimidyl ester labelling.Results:  CD4+ CD25hi Tregs preferentially expressed CCR3, CCR4, CCR5, CCR6 and CCR8. CD4+ CD25hi Tregs responded to the chemokine ligands for CCR4, CCR6 and CCR8 (CCL17, 22, 20 and 1 respectively), with no differences between atopic and nonatopic donors. Over 6‐day allergen stimulation, CD4+ CD25+ T‐cells downregulated CCR4 and upregulated CCR7, in contrast to CD4+ CD25− effector cells, which downregulated CCR7 and upregulated CCR4.Conclusions:  CCR4, CCR6 and CCR8 have potential roles in localization of both CD4+ CD25+ regulatory and CD4+ CD25− effector T cells to sites of allergic inflammation. Upregulation of CCR7 and downregulation of CCR4 upon allergen stimulation of Tregs may allow their recirculation from sites of inflammation, in contrast to retention of effector T cells.
The polymorphisms of interleukin 17A (IL17A) gene and its association with pediatric asthma in Taiwanese population
Authors: Wang J. Y. , Shyur S. D. , Wang W. H. , Liou Y. H. , Lin C. G. J. , Wu Y. J. , Wu L. S. H. 
Published: February 2009

Background:  The interleukin 17A (IL17A) gene, located on chromosome 6p and linked to asthma phenotype, is a highly potential candidate gene conferring asthma susceptibility. The purpose of this study was to investigate the genetic association between single nucleotide polymorphisms (SNPs) of IL17A and asthma in Taiwanese children.Methods:  We selected and performed genotyping on nine SNPs that encompass the genomic region of IL17A in Taiwanese children with or without asthma. A total of 1939 subjects containing 1027 subjects in testing group and 931 subjects in validation group were recruited in this study.Results:  After Bonferroni correction, SNP rs8193036 was found to have a weak association (P = 0.0074 × 9 = 0.066) in genotype frequency test. This association was confirmed by validation group. Logistic regression adjusted allergy comorbidity and gender showed a slightly weaker association.Conclusions:  The results indicated an independent role of IL17A promoter polymorphism rs8193036 in the association with pediatric asthma in Taiwanese population.
Reorganization of cortical hand representation in congenital hemiplegia
Authors: Vandermeeren Yves , Davare Marco , Duque Julie , Olivier Etienne 
Published: February 2009

AbstractWhen damaged perinatally, as in congenital hemiplegia (CH), the corticospinal tract usually undergoes an extensive reorganization, such as the stabilization of normally transient projections to the ipsilateral spinal cord. Whether the reorganization of the corticospinal projections occurring in CH patients is also accompanied by a topographical rearrangement of the hand representations in the primary motor cortex (M1) remains unclear. To address this issue, we mapped, for both hands, the representation of the first dorsal interosseous muscle (1DI) in 12 CH patients by using transcranial magnetic stimulation co‐registered onto individual three‐dimensional magnetic resonance imaging; these maps were compared with those gathered in age‐matched controls (n = 11). In the damaged hemisphere of CH patients, the representation of the paretic 1DI was either found in the hand knob of M1 (n = 5), shifted caudally (n = 5), or missing (n = 2). In the intact hemisphere of six CH patients, an additional, ipsilateral, representation of the paretic 1DI was found in the hand knob, where it overlapped exactly the representation of the non‐paretic 1DI. In the other six CH patients, the ipsilateral representation of the paretic 1DI was either shifted caudally (n = 2) or was lacking (n = 4). Surprisingly, in these two subgroups of patients, the representation of the contralateral non‐paretic 1DI was found in a more medio‐dorsal position than in controls. The present study demonstrates that, besides the well‐known reorganization of the corticospinal projections, early brain injuries may also lead to a topographical rearrangement of the representations of both the paretic and non‐paretic hands in M1.
Hemispheric differences in basilar dendrites and spines of pyramidal neurons in the rat prelimbic cortex: activity‐ and stress‐induced changes
Authors: Perez‐Cruz Claudia , Simon Mária , Czéh Boldizsár , Flügge Gabriele , Fuchs Eberhard 
Published: February 2009

AbstractPyramidal neurons of the rat medial prefrontal cortex have been shown to react to chronic stress by retracting their apical dendrites and by spine loss. We extended these findings by focusing on the basilar dendritic tree of layer III pyramidal neurons in both hemispheres of the rat prelimbic cortex. Animals were subjected to daily restraint stress for 1 week (6 h/day), during either the resting or the activity period. The morphology of basilar dendrites and spines of Golgi–Cox‐stained neurons in the left and right hemispheres was digitally reconstructed and analyzed. We observed the following: (i) there was an inherent hemispheric asymmetry in control rats during the resting period: the number of spines on proximal dendrites was higher in the left than in the right hemisphere; (ii) basal dendrites in controls displayed a diurnal variation: there was more dendritic material during the resting period than in the activity period; (iii) chronic stress reduced the length of basal dendrites in only the right prelimbic cortex; (iv) chronic stress reduced spine density on proximal basal dendrites; (v) restraint stress during the activity period had more pronounced effects on the physiological stress parameters than restraint stress during the resting period. Our results show dynamic hemisphere‐dependent structural changes in pyramidal neurons of the rat prelimbic cortex that are tightly linked to periods of resting and activity. These morphological alterations reflect the capacity of the neurons to react to external stimuli and mirror presumptive changes in neuronal communication.
A common gene exclusion mechanism used by two chemosensory systems
Authors: Capello Luca , Roppolo Daniele , Jungo Véronique Pauli , Feinstein Paul , Rodriguez Ivan 
Published: February 2009

AbstractSensory coding strategies within vertebrates involve the expression of a limited number of receptor types per sensory cell. In mice, each vomeronasal sensory neuron transcribes monoallelically a single V1R pheromone receptor gene, chosen from a large V1R repertoire. The nature of the signals leading to this strict receptor expression is unknown, but is apparently based on a negative feedback mechanism initiated by the transcription of the first randomly chosen functional V1R gene. We show, in vivo, that the genetic replacement of the V1rb2 pheromone receptor coding sequence by an unrelated one from the odorant receptor gene M71 maintains gene exclusion. The expression of this exogenous odorant receptor in vomeronasal neurons does not trigger the transcription of odorant receptor‐associated signalling molecules. These results strongly suggest that despite the different odorant and vomeronasal receptor expression sites, function and transduction cascades, a common mechanism is used by these chemoreceptors to regulate their transcription.
Neurokinin 1 receptor‐expressing projection neurons in laminae III and IV of the rat spinal cord have synaptic AMPA receptors that contain GluR2, GluR3 and GluR4 subunits
Authors: Todd Andrew J. , Polgár Erika , Watt Christine , Bailey Mark E.S. , Watanabe Masahiko 
Published: February 2009

Abstractα‐Amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptors (AMPArs), which mediate fast excitatory glutamatergic transmission, are tetramers made from four subunits (GluR1–4 or GluRA–D). Although synaptic AMPArs are not normally detected by immunocytochemistry in perfusion‐fixed tissue, they can be revealed by using antigen retrieval with pepsin. All AMPAr‐positive synapses in spinal cord are thought to contain GluR2, while the other subunits have specific laminar distributions. GluR4 can be alternatively spliced such that it has a long or short cytoplasmic tail. We have reported that <10% of AMPAr‐containing synapses in lamina II have the long form of GluR4, and that these are often arranged in dorsoventrally orientated clusters. In this study, we test the hypothesis that GluR4‐containing receptors are associated with dorsal dendrites of projection neurons in laminae III and IV that express the neurokinin 1 receptor (NK1r). Immunostaining for NK1r was carried out before antigen retrieval, and sections were then reacted to reveal GluR2 and either GluR4 (long form), GluR3 or GluR1. All NK1r‐positive lamina III/IV neurons had numerous GluR2‐immunoreactive puncta in their dendritic plasma membranes, and virtually all (97%) of the puncta tested were labelled (usually strongly) with the GluR4 antibody. Sizes of puncta varied, but many were elongated and they were significantly larger than nearby puncta that were not associated with the NK1r cells. None of the GluR2 puncta on these cells was positive for GluR1, while 85% were GluR3‐immunoreactive. These results show that synaptic AMPArs on the dendrites of the lamina III/IV NK1r projection neurons contain GluR2, GluR3 and GluR4, but not GluR1 subunits.
Anorectal manometry with water‐perfused catheter in healthy adults with no functional bowel disorders
Authors:   Gruppo Lombardo per lo Studio della Motilità Intestinale
Published: February 2009

AbstractAnorectal manometry provides an objective assessment of anal sphincter pressure and rectal sensitivity and anorectal reflexes in response to distension. However, its clinical utility is hampered by a lack of standardized protocols and normative data from healthy subjects. Previous studies have used water‐perfused systems in normal subjects, but some adopted a rapid pull‐through technique; others did not evaluate rectal sensations and others did not carefully exclude patients with functional bowel disorders.Objective  To evaluate anorectal function in healthy adults without functional bowel disorders, using a water‐perfused system with the stationary technique in order to obtain normative values for anorectal manometry.Method  Fifty‐two healthy volunteers with no Rome II diagnostic criteria for functional bowel disorders, including only nulliparous women, underwent anorectal manometry with a water‐perfused system, according to a standardized protocol.Results  Maximum squeeze pressure of the anal sphincter as well as the area under the pressure‐time curve during squeeze was significantly lower in women than men (P < 0.01), while sphincter length, resting pressure, volume thresholds for reflex inhibitory recto‐anal and rectal sensations were similar.Conclusions  This study describes a protocol for stationary anorectal manometry using a water‐perfused system, and a method for analysing the various parameters obtained during the procedure, as recently suggested in the international literature. It supplies normative data obtained in a population of healthy subjects including nulliparous women, with no functional bowel disorders.
Capecitabine plus oxaliplatin vs fluorouracil plus oxaliplatin as first line treatment for metastatic colorectal caner – meta‐analysis of six randomized trials
Authors: Cao Y. , Liao C. , Tan A. , Liu L. , Mo Z. , Gao F. 
Published: February 2009

AbstractObjective  This meta‐analysis was performed to evaluate the efficacy and safety of capecitabine plus oxaliplatin vs fluorouracil (FU) plus oxaliplatin as first line treatment for metastatic or advanced colorectal cancer.Method  A total of 2196 patients from six randomized controlled trials were available for analysis, which included 1105 patients in capecitabine plus oxaliplatin group and 1091 patients in FU plus oxaliplatin group. The efficacy data included overall survival (OS), progression‐free survival (PFS), time to treatment failure (TTF), overall response rate (ORR), and the safety data contained specific grade 3 and 4 toxicity such as anaemia, thrombocytopenia, neutropenia, diarrhoea, nausea, asthenia, vomiting, abdominal pain, hand foot syndrome, neuropathy and stomatitis were evaluated.Results  Pooled analysis of OS (hazards ratio HR = 1.04, 95%CI: 0.95–1.14), PFS (1.08, 0.98–1.18), ORR (odds ratio OR = 0.87, 0.73–1.03) in the capecitabine plus oxaliplatin group shows no statistical significance when compared with those in the FU plus oxaliplatin group. The statistically significant differences in pooled estimates suggest a higher incidence of grade 3/4 thrombocytopenia (OR = 1.87, 1.24–2.81), grade 3/4 hand‐foot syndrome (3.90, 2.13–7.12) in the capecitabine plus oxaliplatin group and grade 3/4 neutropenia (0.20, 0.07–0.53) in the FU plus oxaliplatin group. No statistically significant difference was noted in the incidence of grade 3/4 anaemia, asthenia, diarrhoea, nausea, vomiting, abdominal pain, neuropathy and stomatitis.Conclusion  The effect of capecitabine plus oxaliplatin regimen is similar to FU plus oxaliplatin regimen as first line treatment for metastatic colorectal cancer, but it offers advantages of simplicity and convenience to administer.