bluuebunny/crossref_metadata_2025_split huggingface dataset:
The development of atopic dermatitis is independent of Immunoglobulin E up‐regulation in the K14‐IL‐4 SKH1 transgenic mouse model
Authors: Chen L. , Overbergh L. , Mathieu C. , Chan L. S. 
Published: April 2008

SummaryBackground
We have successfully generated an IgE‐associated (extrinsic/allergic) mouse model of atopic dermatitis in K14‐IL‐4‐Tg/CByB6 mice. The newly described subset of non‐IgE‐associated (intrinsic/non‐allergic) atopic dermatitis in human patients raises the question on the role of IgE in the pathogenesis.Objective
The aim of this study was to develop a non‐IgE‐associated atopic dermatitis model in K14‐IL‐4‐Tg/SKH1 mice.Methods
K14‐IL‐4‐Tg/CByB6 mice were crossed with SKH1 mice to produce K14‐IL‐4‐Tg/SKH1 mice. Phenotypes of clinical and histological, cytokine expression in the skin lesions, and total serum IgE in K14‐IL‐4‐Tg/CByB6 and K14‐IL‐4‐Tg/SKH1 mice were compared. The CD40 and CD40L on T and B cells were also studied to differentiate their roles in IgE production.Results
K14‐IL‐4‐Tg/SKH1mice had a normal total serum IgE level and manifested a chronic inflammatory skin phenotype identical to that of K14‐IL‐4‐Tg/CByB6 IgE‐mediated mice in clinical morphology, histology, infiltration of mononuclear cells/eosinophils/mast cells, mast cell degranulation, and up‐regulation of chronic lesional cytokine mRNA expression of IL‐1β, IL‐3, IL‐4, IL‐6, IL‐10, IL‐12, IL‐13, IFN‐γ, TNF‐α, and TNF‐β. We also found that the inability of CD4+ T cells of the K14‐IL‐4‐Tg/SKH1mice to up‐regulate CD40L expression upon stimulation might account for their inability to up‐regulate the IgE level. B cell abnormality was ruled out as CD19+ B cells of K14‐IL‐4‐Tg/SKH1 mice synthesized the same amount of IgE in vitro compared with K14‐IL‐4‐Tg/CByB6 mice in the presence of IL‐4 and soluble CD40L. Our studies further suggested that the defect of early growth response‐1 in T cells might be responsible for the impaired CD40L up‐regulation in K14‐IL‐4‐Tg/SKH1 mice.Conclusion
K14‐IL‐4‐Tg/SKH1 mice developed skin inflammation that resembled human intrinsic atopic dermatitis. Therefore, this model may be suitable to study the pathogenesis of intrinsic atopic dermatitis.
Detection of somatic β‐catenin mutations in primary pigmented nodular adrenocortical disease (PPNAD)
Authors: Tadjine Mimi , Lampron Antoine , Ouadi Lydia , Horvath Anelia , Stratakis Constantine A. , Bourdeau Isabelle 
Published: April 2008

SummaryBackground  Primary pigmented nodular adrenocortical disease (PPNAD) leads to Cushing syndrome (CS) and is often associated with Carney complex (CNC). Genetic alterations of the type 1‐α regulatory subunit of cAMP‐dependent protein kinase A (PRKAR1A) and phosphodiesterase 11A4 (PDE11A) genes have been found in PPNAD. Recent studies have demonstrated that β‐catenin mutations are frequent in adrenocortical adenomas and carcinomas and that the Wnt‐signalling pathway is involved in PPNAD tumorigenesis. We hypothesized that adrenocortical adenomas that form in the context of PPNAD may harbour β‐catenin mutations.Methods  We studied 18 patients with CS secondary to PPNAD who were screened for germline PRKAR1A and PDE11A mutations. Tumor DNA was extracted from pigmented adrenocortical adenoma and nodular adrenal hyperplasia. Mutation analysis of exons 3 and 5 of β‐catenin was performed using polymerase chain reaction and direct sequencing. Sections from formalin‐fixed, paraffin‐embedded tumour samples were studied by immunohistochemistry with an antibody against β‐catenin.Results  Nine patients were carrying germline PRKAR1A mutations and one patient had a PDE11A mutation. We found somatic β‐catenin mutations in 2 of 18 patients (11%). In both cases, the mutations occurred in relatively large adenomas that had formed in the background of PPNAD. Tumor DNA analysis revealed a heterozygous ACC‐to‐GCC missense mutation in codon 41 (T41A) and a TCT‐to‐CCT missense mutation in codon 45 (S45P) of exon 3 of the β‐catenin gene that was confirmed at the cDNA level. There were no alterations in the DNA of PPNAD‐adjacent tissues and lymphocytes from the patients, indicating somatic events. Immunohistochemistry showed nuclear accumulation of β‐catenin in more than 90% of cells in adenomatous tissue whereas no nuclear immunoreactivity was detected in adjacent PPNAD nodular cells. Nuclear translocation of β‐catenin protein in the PPNAD adenoma suggests activation of the Wnt–β‐catenin pathway in PPNAD.Conclusions  We report, for the first time, β‐catenin mutations in adenomas associated with PPNAD, further implicating Wnt–β‐catenin signalling in tumorigenesis linked to bilateral adrenal hyperplasias.
A comparison of the relative contributions of temporal and spatial variation in the density of drifting invertebrates in a Dorset (U.K.) chalk stream
Authors: NEALE MARTIN W. , DUNBAR MICHAEL J. , JONES J. IWAN , IBBOTSON ANTON T. 
Published: April 2008

Summary1. Invertebrate drift is commonly investigated in streams, with the majority of studies focussed on temporal (typically diel) variation. In comparison, few studies have investigated spatial variation in drift and there is little consensus among them. We tested the hypothesis that spatial variation in invertebrate drift is as important as temporal variation.2. The density of drifting invertebrates in a chalk stream was sampled using an array of nets arranged to determine vertical, lateral and longitudinal variation. Samples were collected at dawn, during the day, at dusk and by night, on four separate monthly occasions. Insecta and Crustacea were analysed separately to identify the effect of differing life history strategies. The density of drifting debris was also recorded, to act as a null model.3. Time of day and vertical position together explained the majority of the variance in invertebrate drift (79% for Insecta and 97% for Crustacea), with drift densities higher at dusk and night, and nearer the stream bed. Independently, time of day (38%, Insecta; 52%, Crustacea) and vertical position (41%, Insecta; 45%, Crustacea) explained a similar amount of the observed variance. Month explained some of the variance in insect drift (9%) but none for Crustacea.4. Variation in the density of drifting debris showed little in common with invertebrate drift. There was little variation associated with time of day and only 27% of the observed variation in debris could be explained by the factors investigated here, with month explaining the largest proportion (20%). We suggest the difference in drifting debris and invertebrates provides further evidence for a strong behavioural component in invertebrate drift.5. Spatial variation in invertebrate drift can be of the same order of magnitude as the much‐described diel temporal variation. The extent of this spatial variation poses problems when attempting to quantify invertebrate drift and we recommend that spatial replication should be incorporated into drift studies.
Cysteine protease cathepsin X modulates immune response via activation of β2 integrins
Authors: Obermajer Nataša , Repnik Urška , Jevnikar Zala , Turk Boris , Kreft Marko , Kos Janko 
Published: April 2008

SummaryCathepsin X is a lysosomal, cysteine dependent carboxypeptidase. Its expression is restricted to cells of the immune system, suggesting a function related to the processes of inflammatory and immune responses. It has been shown to stimulate macrophage antigen‐1 (Mac‐1) receptor‐dependent adhesion and phagocytosis via interaction with integrin β2 subunit. Here its potential role in regulating lymphocyte proliferation via Mac‐1 and the other β2 integrin receptor, lymphocyte function‐associated antigen‐1 (LFA‐1) has been investigated. Cathepsin X has been shown to suppress proliferation of human peripheral blood mononuclear cells, by activation of Mac‐1, known as a suppressive factor for lymphocyte proliferation. On the other hand, co‐localization of cathepsin X and LFA‐1 supports the role of cathepsin X in regulating LFA‐1 activity, which enhances lymphocyte proliferation. As shown by fluorescence resonance energy transfer, using U‐937 and Jurkat cells transfected with αL‐mCFP and β2‐mYFP, recombinant cathepsin X directly activates LFA‐1. The activation was confirmed by increased binding of monoclonal antibody 24, recognizing active LFA‐1. We demonstrate that cathepsin X is involved in the regulation of two β2 integrin receptors, LFA‐1 and Mac‐1, which exhibit opposing roles in lymphocyte activation.
H2‐Dd‐mediated upregulation of interleukin‐4 production by natural killer T‐cell and dendritic cell interaction
Authors: Mizuuchi Kazuomi , Yanagawa Yoshiki , Iwabuchi Kazuya , Namba Kenichi , Kitaichi Nobuyoshi , Ohno Shigeaki , Onoé Kazunori 
Published: April 2008

SummaryNatural killer T (NKT) cells are capable of subserving apparently opposite functions, the interferon‐γ (IFN‐γ)‐mediated enhancement of host defence and interleukin‐4 (IL‐4) ‐mediated immune regulation. Although dendritic cells (DCs) potently activate NKT cells, DC regulation of the IL‐4–IFN‐γ balance via NKT‐cell activation is not well characterized. In the present study, we examined the effect of DC treatment with CpG oligodeoxynucleotide (ODN), a Toll‐like receptor 9 ligand, on the induction of NKT‐cell cytokine production. CpG‐ODN‐conditioned and α‐galactosylceramide (α‐GalCer)‐loaded myeloid DCs (CpG‐DCs) from BALB/c mice showed enhanced ability to induce NKT‐cell production of IL‐4, but not IFN‐γ, compared to α‐GalCer‐loaded control DCs (not treated with CpG‐ODN). The CpG‐DCs expressed significantly higher levels of H2‐Dd than control DCs, and blocking of the H2‐Dd and Ly49 receptor interaction during antigen presentation completely abolished the enhanced ability of the CpG‐DCs to induce NKT‐cell production of IL‐4. These findings demonstrate that DC recognition of the CpG motif leads to induction of enhanced IL‐4 production by NKT cells via interaction of the augmented H2‐Dd with Ly49 receptors on NKT cells.
Ex vivo evaluation of the effectiveness of bleaching agents on the shade alteration of blood‐stained teeth
Authors: Yui K. C. K. , Rodrigues J. R. , Mancini M. N. G. , Balducci I. , Gonçalves S. E. P. 
Published: April 2008

AbstractAim  To evaluate ex vivo effectiveness of the three formulations of bleaching materials for intracoronal bleaching of root filled teeth using the walking bleach technique.Methodology  Extracted premolar teeth were stained artificially with human blood. After biomechanical preparation, the root canals were filled and a 3‐mm thick intermediate base of zinc phosphate cement was placed at the level of the cementoenamel junction. The teeth were divided into four groups (n = 12): C (control, without bleaching material), A1 (sodium perborate + distilled water), A2 (sodium perborate + 10% carbamide peroxide) and A3 (sodium perborate + 35% carbamide peroxide). The bleaching materials were changed at 7 and 14 days. Evaluation of shade was undertaken with aid of the VITA Easyshade™ (ΔE*ab) and was performed after tooth staining and at 7, 14 and 21 days after bleaching, based on the CIELAB system. Data were analysed by anova for repeated measurements, Tukey and Dunnett tests (α = 0.05).Results  The Tukey test revealed that group A1 (10.58 ± 4.83 ΔE*ab) was statistically different from the others (A2, 19.57 ± 4.72 ΔE*ab and A3, 17.58 ± 3.33 ΔE*ab), which were not different from each other. At 7 days: A1 was significantly different from A2; at 14 and 21 days: A2 and A3 were significantly better than A1; the Dunnett test revealed that the control group was different from A1, A2 and A3 at all periods (P < 0.05).Conclusion  Sodium perborate associated with both 10% and 35% carbamide peroxide was more effective than when associated with distilled water.
The technical quality of nonsurgical root canal treatment performed by a selected cohort of Australian endodontists
Authors: Bierenkrant D. E. , Parashos P. , Messer H. H. 
Published: April 2008

AbstractAim  To investigate the technical quality of nonsurgical root canal treatment performed by endodontists in Melbourne, Australia.Methodology  Clinical and radiographic records of 100 sequential nonsurgical patients were obtained from each of six endodontists working in private practice. The following variables were analysed: proximity of root filling to radiographic apex; homogeneity and radiodensity of root filling; lateral adaptation of the root filling to the canal walls; taper; extrusion of material; small, appropriate or excessive apical enlargement; presence of lateral canals; transportation; procedural errors. The radiographs were assessed by three independent evaluators. Exploratory data analysis was undertaken using simple frequencies and cross‐tabulations. A generalised linear mixed model (GLMM) was used for the formal statistical modelling.Results  Of the 1351 canals that were examined, 91.7% were filled within 2 mm of the radiographic apex and 74% were within 1 mm. Homogeneity and adequate density were found along the entire length of the canal in 86.1% and 88.6% of cases respectively. Lateral adaptation was adequate in 95.6% of cases and the taper was ‘smooth and continuous’ in 83.8% of roots. No and/or small extrusion of sealer was noted in 98.3% of cases. Apical enlargement was ‘appropriate’ in 85% of roots. Both transportation (1.1%) and procedural errors (1.3%) were rare occurrences.Conclusions  The technical quality of root fillings performed by endodontists in Melbourne, Australia complied with current guidelines in 77.4%–91.0% of roots. All variables examined confirmed high levels of technical proficiency. There were very few instances of canal transportation and/or procedural errors.
The varying role of population abundance in structuring indices of biotic homogenization
Authors: Cassey Phillip , Lockwood Julie L , Olden Julian D , Blackburn Tim M 
Published: April 2008

AbstractAim An important component of human‐induced global change is the decrease or increase in community distinctiveness (taxonomic homogenization or differentiation, respectively) that follows the loss of native species and gain of non‐native species. We use simulation approaches to assess the extent to which conclusions about the outcome of the homogenization process depend on whether or not abundance data are incorporated.Location Data were produced through computer simulation.Methods The frequency with which occurrence‐based similarity indices and abundance‐based similarity indices give different views of changes in community similarity, and the conditions under which such differences occurred were assessed using both deterministic and stochastic modelling approaches to simulate species assemblage states.Results Occurrence‐based and abundance‐based indices were positively correlated across the set of simulations for both the deterministic and stochastic models. However, in both situations approximately one quarter (25%) of models resulted in contrasting outcomes for the two approaches of calculating changes in compositional similarity; that is, one data type showed a positive value (homogenization), whereas the other showed a negative value (differentiation).Main conclusions In the majority of cases, species abundances will not change drastically enough after perturbation to produce large differences between homogenization scores measured using occurrence versus abundance information. However, in cases where these changes are large, it is important to recognize that the choice of metric to analyse homogenization trends will influence the qualitative and quantitative conclusions drawn. Studies of real assemblages are therefore necessary to evaluate the role of species abundance in defining the magnitude and direction of changes in community composition across space, and the implications of these changes for native biodiversity.
Nectar‐feeding bird and bat niches in two worlds: pantropical comparisons of vertebrate pollination systems
Authors: Fleming Theodore H. , Muchhala Nathan 
Published: April 2008

AbstractAim We review several aspects of the structure of regional and local assemblages of nectar‐feeding birds and bats and their relationships with food plants to determine the extent to which evolutionary convergence has or has not occurred in the New and Old World tropics.Location Our review is pantropical in extent and also includes the subtropics of South Africa and eastern Australia. Within the tropics, it deals mostly with lowland forest habitats.Methods An extensive literature review was conducted to compile data bases on the regional and local species richness of nectar‐feeding birds and bats, pollinator sizes, morphology, and diets. Coefficients of variation (CVs) were used to quantify the morphospace occupied by the various families of pollinators. The extent to which plants have become evolutionarily specialized for vertebrate pollination was explored using several criteria: number and diversity of growth forms of plant families providing food for all the considered pollinator families; the most common flower morphologies visited by all the considered pollinator families; and the number of plant families that contain genera with both bird‐ and bat‐specialized species.Results Vertebrate pollinator assemblages in the New World tropics differ from those in the Old World in terms of their greater species richness, the greater morphological diversity of their most specialized taxa, and the greater degree of taxonomic and ecological diversity and morphological specialization of their food plants. Within the Old World tropics, Africa contains more specialized nectar‐feeding birds than Asia and Australasia; Old World nectar‐feeding bats are everywhere less specialized than their New World counterparts.Main conclusions We propose that two factors – phylogenetic history and spatio‐temporal predictability (STP) of flower resources – largely account for hemispheric and regional differences in the structure of vertebrate pollinator assemblages. Greater resource diversity and resource STP in the New World have favoured the radiation of small, hovering nectar‐feeding birds and bats into a variety of relatively specialized feeding niches. In contrast, reduced resource diversity and STP in aseasonal parts of Asia as well as in Australasia have favoured the evolution of larger, non‐hovering birds and bats with relatively generalized feeding niches. Tropical Africa more closely resembles the Neotropics than Southeast Asia and Australasia in terms of resource STP and in the niche structure of its nectar‐feeding birds but not its flower‐visiting bats.
Identification of glacial refugia in south‐eastern North America by phylogeographical analyses of a forest understorey plant, Trillium cuneatum
Authors: Gonzales Eva , Hamrick James L. , Chang Shu‐Mei 
Published: April 2008

AbstractAim  We examine several hypotheses emerging from biogeographical and fossil records regarding glacial refugia of a southern thermophilic plant species. Specifically, we investigated the glacial history and post‐glacial colonization of a forest understorey species, Trillium cuneatum. We focused on the following questions: (1) Did T. cuneatum survive the Last Glacial Maximum (LGM) in multiple refugia, and (if so) where were they located, and is the modern genetic structure congruent with the fossil record‐based reconstruction of refugia for mesic deciduous forests? (2) What are the post‐glacial colonization patterns in the present geographical range?Location  South‐eastern North America.Methods  We sampled 45 populations of T. cuneatum throughout its current range. We conducted phylogeographical analyses based on maternally inherited chloroplast DNA (cpDNA haplotypes) and used TCS software to reconstruct intraspecific phylogeny.Results  We detected six cpDNA haplotypes, geographically highly structured into non‐overlapping areas. With one exception, none of the populations had mixed haplotype composition. TCS analysis resulted in two intraspecific cpDNA lineages, with one clade subdivided further by shallower diversification.Main conclusions  Our investigation revealed that T. cuneatum survived the LGM in multiple refugia, belonging to two (western, eastern) genealogical lineages geographically structured across south‐eastern North America. The western clade is confined to the south‐western corner of T. cuneatum’s modern range along the Lower Mississippi Valley, where fossil records document a major refugium of mesic deciduous forest. For the eastern clade, modern patterns of cpDNA haplotype distribution suggest cryptic vicariance, in the form of forest contractions and subsequent expansions associated with Pleistocene glacial cycles, rather than simple southern survival and subsequent northward colonization. The north–south partitioning of cpDNA haplotypes was unexpected, suggesting that populations of this rather southern thermophilic species may have survived in more northern locations than initially expected based on LGM climate reconstruction, and that the Appalachian Mountains functioned as a barrier to the dispersal of propagules originating in more southern refugia. Furthermore, our results reveal south‐west to north‐east directionality in historical migration through the Valley and Ridge region of north‐west Georgia.
The canopy beetle faunas of Gondwanan element trees in Chilean temperate rain forests
Authors: Arias Elizabeth T. , Richardson Barry J. , Elgueta Mario 
Published: April 2008

AbstractAim  To describe the coleopteran fauna occurring in canopies of temperate Gondwanan tree species in terms of their diversity and guild and taxonomic structures, and to test the proposition that this structuring reflects the Gondwanan origins of this fauna.Location  The Andes and the coastal cordillera of temperate Chile.Methods  Canopy fogging was used to sample beetles from 29 trees. The samples were statistically described using Schao and the Simpson diversity index D. Cluster analyses and multi‐dimensional scaling (MDS) were performed. The taxonomic and guild structures of the Chilean coleopteran fauna were compared quantitatively with those found in other parts of the world using homogeneity chi‐square and t‐tests.Results  A collection of 25,497 beetle specimens was obtained primarily from Nothofagus dombeyi, Nothofagus obliqua and Araucaria araucana. The specimens collected were distributed between 485 morphospecies and included 107 putative, new generic‐level taxa and 223 apparently undescribed species. Estimates of the size of the canopy beetle fauna showed that 600+ species were likely to be present. The communities found on a tree species differed markedly between years. MDS plots showed less community divergence between tree species for predators than for phytophages and xylophages. The guild structure was similar to that found on Australian ‘Gondwanan’ trees but differed significantly from the community structures found on ‘Laurasian’ tropical and temperate trees in supporting fewer phytophages and saprophages, but more xylophages. The predator guild showed a different pattern, with tropical faunas differing from those of more temperate regions, irrespective of hemisphere, as did the distribution of superfamilies.Main conclusions  The beetle fauna found in the canopies of N. dombeyi, N. obliqua and A. araucana was large (600+ species), with about half of the species undescribed. Schao was found to vary with sample size and to give lower estimates of S than species attenuation curves, raising the possibility that the two methods are estimating the sizes of different statistical communities. It is possible that the attenuation curve is estimating the number of species to be found on a particular tree species, while Schao is estimating the ‘carrying capacity’ for beetle species of individual trees, and this varies from tree to tree. Care also needs to be taken in experimental design when monitoring temporal changes in forest insect communities given the difference in communities found between years in this study. The proportions of phytophages, saprophages and xylophages resemble those of a ‘Gondwanan’ rain forest from Australia and differ significantly from those of tropical and temperate ‘Laurasian’ forests.