bluuebunny/crossref_metadata_2025 huggingface dataset:
Meta-analysis of myeloperoxidase G-463/A polymorphism in anti-neutrophil cytoplasmic autoantibody-positive vasculitis
Authors: Rajp A , Adu D , Savage C O
Published: October 2009

Wegener's granulomatosis, microscopic polyangiitis and Churg Strauss syndrome are small-vessel vasculitides associated with anti-neutrophil cytoplasmic antibodies (ANCA) directed against proteinase 3 (PR3) and myeloperoxidase (MPO). A G to A polymorphism at position 463 in the promoter region of the MPO gene, which leads to the loss of a SP1 transcription binding site in an Alu hormone responsive element, reduces MPO expression. We hypothesized that MPO alleles may play a role in determining disease susceptibility or severity in ANCA-associated vasculitis (AASV). MPO genotypes were determined by restriction fragment length polymorphism polymerase chain reaction (RFLP/PCR) in 134 Caucasian patients (Wegener's granulomatosis, n = 69; microscopic polyangiitis, n = 65; PR3–ANCA n = 91; MPO–ANCA, n = 43) and 150 matched healthy controls. There was no difference in survival to renal failure or death in patients with the different MPO alleles (χ2 = 0·904, P = 0·6362) or in presenting serum creatinine concentration based on MPO genotype (χ2 = 0·389, P = 0·8232). There was no significant difference in genotype frequencies between controls (13AA, 102GG, 35GA) and patients (14AA, 97GG, 23GA: χ2 = 1·75, P = 0·417), patients with Wegener's granulomatosis (5AA, 53GG, 11GA: χ2 = 1·864, P = 0·3938) or patients with microscopic polyangiitis (9AA, 44GG, 12GA: χ2 = 1·682, P = 0·4317). A meta-analysis of our study and two previous studies showed that there was no association between the myeloperoxidase G-463/A polymorphism and the risk of developing ANCA-associated vasculitis; GG versus GA plus AA (odds ratio 1·14; 95% confidence interval 0·86–1·50). The MPO G-463/A polymorphism is not a risk factor for the development or severity of AASV.
The role of CD11c+ hepatic dendritic cells in the induction of innate immune responses
Authors: Shu S-A , Lian Z-X , Chuang Y-H , Yang G-X , Moritoki Y , Comstock S S , Zhong R-Q , Ansari A A , Liu Y-J , Gershwin M E
Published: October 2009

The role of the liver in the initiation and maintenance of tolerance is a critical immune function that involves multiple lineages of immune cells. Included within these populations are liver dendritic cells (DCs). Although there has been significant work on the phenotypic and functional roles of splenic and bone marrow dendritic cells, as well as their subsets, comparable studies in liver have often been difficult. To address this issue we have isolated, from C57BL/6 mice, relatively pure populations of DCs and compared phenotype and function to the data from spleen using flow cytometry, cell sorter assisted purification and culture, morphology by cytospin and May–Giemsa staining, cell cycle progression, antigen uptake, cytokine production and allo-activation potential. natural killer (NK)1·1–CD11c+ liver DC subsets (conventional DCs, T cell receptor (TcR)β–NK1·1–CD11c+B220– and plasmacytoid DCs, TcRβ–NK1·1–CD11c+B220+) efficiently endocytose dextran and produce significant levels of tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-12 p40 in response to Toll-like receptor (TLR) ligands, with responses higher than splenic DCs. There is also a differential capability of hepatic DCs to respond to innate signals. Indeed, CD11c+ hepatic DCs have a greater capacity to respond to innate stimulation but are less capable of inducing CpG activated-allogeneic T cells. These data suggest that hepatic dendritic cells function as a critical bridge between innate and adaptive immunity and are capable of inducing stronger innate responses with a lower capacity for allo-stimulation than splenic dendritic cells. These properties of liver dendritic cells contribute to their unique role in the induction of tolerance.
Selection of probiotic bacteria for prevention of allergic diseases: immunomodulation of neonatal dendritic cells
Authors: Niers L E M , Hoekstra M O , Timmerman H M , van Uden N O , de Graaf P M A , Smits H H , Kimpen J L L , Rijkers G T
Published: October 2009

Modification of intestinal microbiota early in life by administration of probiotic bacteria may be a potential approach to prevent allergic disease. To select probiotic bacteria for in vivo purposes, we investigated the capacity of probiotic bacteria to interact with neonatal dendritic cells (DC) and studied the ensuing T cell polarizing effect. Immature DC were generated from cord blood-derived monocytes and maturation was induced by maturation factors (MF), lipopolysaccharide (LPS) plus MF and Bifidobacterium bifidum, B. infantis, Lactobacillus salivarius, Lactococcus lactis alone or combined with MF. After 12 days of co-culture with DC and Staphylococcus aureus enterotoxin B (SEB) as antigenic stimulus, cytokine production by autologous T cells was determined by intracellular cytokine staining. Additionally, cells were stimulated with CD3 and CD28 monoclonal antibodies and cytokines were measured in supernatants by multiplex assay. The probiotic strains induced partial maturation of DC. Full maturation of DC was induced for all strains tested when MF was added. The percentage of interleukin (IL)-4 producing T cells was lower in T cell cultures stimulated with B. bifidum matured DC compared to MF and LPS matured DC, which coincided with a higher percentage of interferon (IFN)-γ-producing T cells. Furthermore, T cells stimulated by B. bifidum matured DC produced significantly more IL-10 compared to MF matured DC. Selected species of the Bifidobacterium genus prime in vitro cultured neonatal DC to polarize T cell responses and may therefore be candidates to use in primary prevention of allergic diseases.
Interferon-γ does not break, but promotes the immunosuppressive capacity of adult human mesenchymal stem cells
Authors: Ryan J M , Barry F , Murphy J M , Mahon B P
Published: October 2009

The ability of mesenchymal stem cells (MSC) to suppress alloresponsiveness is poorly understood. Herein, an allogeneic mixed lymphocyte response was used as a model to investigate the mechanisms of MSC-mediated immunomodulation. Human MSC are demonstrated to express the immunosuppressive cytokines hepatocyte growth factor (HGF), interleukin (IL)-10 and transforming growth factor (TGF)-β1 at concentrations that suppress alloresponses in vitro. MSC also express cyclooxygenase 1 and 2 and produce prostaglandin E2 constitutively. Blocking studies with indomethacin confirmed that prostaglandins contribute to MSC-mediated allosuppression. The proinflammatory cytokine interferon (IFN)-γ did not ablate MSC inhibition of alloantigen-driven proliferation but up-regulated HGF and TGF-β1. IFN-γ also induced expression of indoleamine 2,3, dioxygenase (IDO), involved in tryptophan catabolism. Use of an antagonist, 1-methyl-L-tryptophan, restored alloresponsiveness and confirmed an IDO contribution to IFN-γ-induced immunomodulation by MSC. Addition of the tryptophan catabolite kynurenine to mixed lymphocyte reactions (MLR), blocked alloproliferation. These findings support a model where IDO exerts its effect through the local accumulation of tryptophan metabolites rather than through tryptophan depletion. Taken together, these data demonstrate that soluble factors, or products derived from MSC, modulate immune responses and suggest that MSC create an immunosuppressive microenvironment capable of modulating alloresponsiveness even in the presence of IFN-γ.
Effects of CD40 binding on ovarian carcinoma cell growth and cytokine productionin vitro
Authors: Toutirais O , Gervais A , Cabillic F , Le Gallo M , Coudrais A , Levêque J , Catros-Quemener V , Genetet N
Published: October 2009

The poor prognosis associated with ovarian carcinoma (OVCA) is linked to the high incidence of local recurrence. There is a pressing need to identify factors that can play a role in OVCA growth and spread. Here, we focused on CD40, a member of the tumour necrosis factor (TNF) receptor superfamily with important functions in immune response. The expression of CD40 has been reported on various types of carcinoma cells, but its biological role is still poorly understood. The aim of the present study was to investigate the expression and function of the CD40 in OVCA cell lines. Detectable CD40 levels ranging from low to very high were found on the cell surface of several OVCA cell lines by flow cytometry analysis. Co-culture with a murine cell line transfected with CD40 ligand (CD40L) inhibited cell growth and up-regulated the secretion of proinflammatory cytokines interleukin (IL)-6, IL-8 and TNF-α in high-level CD40-expressing OVCA cell lines. Similarly, an increase of IL-6 and IL-8 release could be obtained by adding a soluble form of CD40L to the OVCA cultures. These results suggest that CD40–CD40L interaction is an important pathway affecting growth regulation and cytokine production in OVCA.
The expanding family of interleukin-1 cytokines and their role in destructive inflammatory disorders
Authors: Barksby H E , Lea S R , Preshaw P M , Taylor J J
Published: October 2009

Understanding cytokine immunobiology is central to the development of rational therapies for destructive inflammatory diseases such as rheumatoid arthritis (RA) and periodontitis. The classical interleukin-1 (IL-1) family cytokines, IL-1α and IL-1β, as well as IL-18, play key roles in inflammation. Recently, other members of the IL-1 family have been identified. These include six cytokines whose genes are located downstream of the genes for IL-1α and IL-1β on chromosome 2 (IL-1F5-10) and also IL-33, which is the ligand for ST2, a member of the IL-1R/Toll-like receptor (TLR) receptor superfamily. IL-1F6, IL-1F8 and Il−1F9 are agonists and, along with their receptor IL-1Rrp2, are highly expressed in epithelial cells suggesting a role in immune defence in the skin and the gastrointestinal (GI) tract including the mouth. Synovial fibroblasts and articular chondrocytes also express IL-1Rrp2 and respond to IL-1F8, indicating a possible role in RA. IL-33 is associated with endothelial cells in the inflamed tissues of patients with RA and Crohn's disease, where it is a nuclear factor which regulates transcription. IL-33 is also an extracellular cytokine: it induces the expression of T helper 2 (Th2) cytokines in vitro and in vivo as well as histopathological changes in the lungs and GI tract of mice. Therapeutic agents which modify IL-1 cytokines (e.g. recombinant IL-1Ra) have been used clinically and others are at various stages of development (e.g. anti-IL-18 antibodies). This review highlights the emerging data on these novel IL-1 cytokines and assesses their possible role in the pathogenesis and therapy of destructive inflammatory disorders such as RA and periodontitis.
Translational Mini-Review Series on Infectious Disease: Congenital cytomegalovirus infection: 50 years on
Authors: Hassan J , Connell J
Published: October 2009

Cytomegalovirus (CMV) is the leading cause of congenital viral infection, with an incidence of 0·5–3% of live births worldwide. Clinical evidence has shown hearing and vision loss, mental retardation and sometimes death in affected newborns. Primary maternal CMV infection during gestation poses a 40% risk of intrauterine transmission in contrast to recurrent infection. European laboratories have made significant progress in the last decade in solving diagnostic problems linked to infection in pregnancy. With the advances in CMV serology, such as detection of anti-CMV IgM by enzyme immunoassays (EIA), confirmed by Western blot, together with seroconversion and anti-CMV IgG avidity evaluation in pregnant mothers, can help to identify recent infection. Preventative measures such as screening for CMV in the routine serological work-up of pregnant women have been introduced in countries such as Spain and Italy. The development of specific T cell-mediated immune responses in mothers, fetus and neonates is now emerging with regard to antigen-specific CD4 and CD8 T cells, differentiation status, proliferative and cytokine responses. A protective vaccine against CMV is a major public health priority and the study of vaccines in animal model systems has identified potential strategies for interrupting transmission and preventing disease in newborns. Congenital CMV infection has a variable outcome and therefore novel diagnostic methods are required to identify those at risk and therapeutic interventions are needed to improve the long-term prognosis of those infected. CMV was first isolated in 1957. We are now 50 years on, so procrastination is not an option.
Resource partitioning and niche hyper‐volume overlap in free‐living Pygoscelid penguins
Authors: Wilson Rory P.
Published: October 2009

1. Species potentially competing for the same resource are considered to be able to co‐exist if they occupy different niches. In an apparent example of this, Adélie, Chinstrap and Gentoo penguins all feed predominantly on krill Euphausea superba at certain sites of sympatry in Antarctica and are proposed to exploit different niche hyper‐volumes via differential area and depth utilization.

2. Patterns of foraging for 49 of these penguins breeding in sympatry were assessed using dead‐reckoning loggers to examine foraging niche overlap.

3. Area use overlaps were 0·29 for Adélie ∩ Chinstrap, 0·44 for Adélie ∩ Gentoo, and 0·40 for Chinstrap ∩ Adélie and depth use overlaps were 0·69 for Adélie ∩ Chinstrap, 0·48 for Adélie ∩ Gentoo, and 0·52 for Chinstrap ∩ Gentoo Penguins.

4. Foraging efficiency was greatest for Adélie Penguins diving near surface waters (0–15 m) while Chinstraps were most efficient at medium depths (15–60 m) and Gentoo Penguins most efficient at deeper depths (> 60 m). There appear to be physiological reasons for this. Penguins primarily exploited those depths where they were most efficient.

5. The overlap for foraging periods was 0·47 for Adélie ∩ Chinstrap, 0·26 for Adélie ∩ Gentoo, and 0·40 for Chinstrap ∩ Gentoo Penguins. Chinstraps foraged primarily at night, Gentoos during the morning and Adélies in the afternoon. Temporal differences in foraging may result in the three species exploiting krill at those depths where it is best adapted to pursue it, this being mediated by the diel vertical migration of krill.

6. Integration of all measured parameters together gives minimal overlap between species with total overlaps of 0·09 for Adélie ∩ Chinstrap, 0·05 for Adélie ∩ Gentoo, and 0·08 for Chinstrap ∩ Gentoo Penguins so it appears that these penguins conform to conventional theory in avoiding competition in areas of sympatry. However, a model incorporating prey movement between hyper‐volumes indicates that penguins may still compete, even in the virtual absence of hyper‐volume overlap.

7. This study shows that Pygoscelid penguin do indeed exploit different hypervolumes in areas of sympatry but that such exploitation of different niches by sympatric species feeding on a common resource does not necessarily result in reduced competition if the mobility of prey is high.
Comparative analysis of changes in gene expression due to RNA melting activities of translation initiation factor IF1 and a cold shock protein of the CspA family
Authors: Phadtare Sangita , Severinov Konstantin
Published: October 2009

In Escherichia coli, temperature downshift elicits cold shock response, which is characterized by induction of cold shock proteins. CspA, the major cold shock protein of E. coli, helps cells to acclimatize to low temperature by melting the secondary structures in nucleic acids and acting as a transcription antiterminator. CspA and its homologues contain the cold shock domain and belong to the oligomer binding protein family, which also includes S1 domain proteins such as IF1. Structural similarity between IF1 and CspA homologues suggested a functional overlap between these proteins. Indeed IF1 can melt secondary structures in RNA and acts as transcription antiterminator in vivo and in vitro. Here, we show that in spite of having these critical activities, IF1 does not complement cold‐sensitivity of a csp quadruple deletion strain. DNA microarray analysis shows that overproduction of IF1 and Csp leads to changes in expression of different sets of genes. Importantly, several genes which were previously shown to require Csp proteins for their expression at low temperature did not respond to IF1. Moreover, in vitro, we show that a transcription terminator responsive to Csp does not respond to IF1. Our results suggest that Csp proteins and IF1 have different sets of target genes as they may be suppressing the function of different types of transcription termination elements in specific genes.
Above‐ and below‐ground competition between barley, wheat, lupin and vetch in a cereal and legume intercropping system
Authors: Mariotti M. , Masoni A. , Ercoli L. , Arduini I.
Published: October 2009

The effects of intercropping on dry weight (DW) of herbage and nitrogen (N) nutrition of plants of two winter cereals, barley and wheat, and two legumes, white lupin and common vetch, were investigated, and above‐ and below‐ground competition were separated in a fully factorial additive design. Intercropping increased DW compared with the sole species and the increase was higher for the cereals and lupin than for cereals and vetch intercropping systems. Above‐ground competition for light reduced DW of cereals and lupin while it did not influence the DW of vetch. Processes involved in below‐ground competition increased shoot growth of cereals and reduced shoot growth of legumes. N nutrition of cereals was enhanced by below‐ground competition with legumes and N nutrition of vetch was enhanced by above‐ground competition with cereals. Cereals had a higher competitive ability than legumes as a result of their below‐ground competitive ability. The interaction between above‐ and below‐competition is not predictable: negative, positive and no interaction (additivity) between different types of competition were found. In low‐input intercropping systems, when a N‐fixing species is present, the mixture of the roots of components is important for the utilization of the soil resources and, when a climbing species is also present, the mixture of shoots can result in an increased utilization of light.
Effects of intercropping and fertilizer application on the yield and nutritive value of maize and amaranth forages in Nigeria
Authors: Olorunnisomo O. A. , Ayodele O. J.
Published: October 2009

Maize and amaranth forages, produced during the wet season, have the potential to bridge the gap in forage supply to ruminants during the dry season in Nigeria. In two growing seasons (2006 and 2007), effects of intercropping and fertilizer application on dry matter (DM) yield and chemical composition of forages, and land use efficiency, were studied in two experiments. The digestibility of sun‐dried or ensiled maize, amaranth or maize–amaranth mixtures was measured using West African dwarf sheep in a third experiment. Maize showed a higher response to fertilizer application than amaranth or maize–amaranth mixtures. With fertilizer application, DM yield varied significantly (P < 0·05) between species and intercropped mixtures. Dry matter yield ranged from 7·1 (amaranth) to 12·6 t ha−1 (maize) in 2006 and 6·9 (amaranth) to 11·3 t ha−1 (70:30 maize–amaranth population mixture) in 2007. Crude protein (CP) concentration of whole plants ranged from 99·0 (maize) to 227·0 g kg−1 DM (amaranth). Dry matter digestibility values of sun‐dried maize, sun‐dried maize:amaranth 50:50 mixture, sun‐dried amaranth, ensiled maize, ensiled maize:amaranth 50:50 mixture and ensiled amaranth were 0·718, 0·607, 0·573, 0·737, 0·553 and 0·526 respectively. Intercropping increased forage yield and land use efficiency compared to amaranth but had no yield advantage over maize. Although DM digestibility of maize was higher than that of amaranth or the maize:amaranth mixture, digestible CP yield ha−1 was higher with amaranth in the cropping mixture, showing that amaranth could complement maize in systems where CP is the limiting factor to livestock production.
Remembering and repeating childhood dental treatment experiences: parents, their children, and barriers to dental care
Authors: SMITH PATRICIA ANNE , FREEMAN RUTH
Published: October 2009

Background.  Despite improvements over the past two decades, caries and its treatment remain a problem for Scottish children.

Aim.  To investigate how the reported childhood dental care experiences of a group of Scottish parents impacted upon the dental treatment they accessed for their children.

Study design.  In‐depth, semi‐structured interviews were conducted with 19 parents of varied age and social background whose children were referred to Dundee Dental Hospital for the assessment of dental extractions. Parents were encouraged to discuss their own and their child’s experiences of dental care. The interview data were systematically coded using key theme headings, and summary charts constructed to facilitate the analysis.

Results.  A sense of ‘uneasiness’ pervaded the parents’ comments and perceptions of the dental care provided for their children. This was conceptualized as parents ‘remembering in words’ and ‘repeating through actions’ their own childhood dental experiences. They remembered and repeated their childhood experiences by delaying dental treatment for themselves and their children.

Conclusions.  Acknowledging the influence of parental dental experience would help ensure that parents of young children access routine care for their children and themselves.
Phylogenetic signatures of facilitation and competition in successional communities
Authors: Verdú Miguel , Rey Pedro J. , Alcántara Julio M. , Siles Gemma , Valiente‐Banuet Alfonso
Published: October 2009

1. The balance between facilitation and competition through time is at the core of models for successional dynamics. However, since the 1980s, the studies of facilitation have shifted away from successional processes. In a return to the traditional roots of the study of facilitation, we assessed the phylogenetic signatures of competition and facilitation in Mediterranean successional communities and compared them with those recently quantified in non‐successional communities of the Mexican desert.

2. Based on previous work, we hypothesized that facilitation between distantly related lineages is an important driver of successional dynamics, as has been shown in non‐successional systems. However, we also predicted that the balance between facilitation and competition will be different in successional systems because many species disappear from communities during the process of succession, which does not occur in non‐successional systems.

3. We sampled plant species composition over a chronosequence of post‐fire succession and predicted phylogenetic clustering in communities at the early stages caused by species that reproduce by seed (‘seeders’, belonging to a few specific families) being favoured by fire; overdispersion in intermediate stages driven by facilitation interactions among distantly related species; and randomness in the final stage caused by the competitive exclusion of pioneer species belonging to a few families and the survival of species in many other families.

4. In the pioneer stage, we found a random phylogenetic pattern because seeders and many resprouter species were present at this stage, indicating that autosuccession was also occurring. In intermediate phases, once pioneers had recruited into open spaces and facilitated late‐successional species, most of which were ancient taxa originating during the Tertiary, phylogenetic overdispersion predominated. Finally, in the later stages competitive exclusion of pioneer species reduced phylogenetic diversity, leading to a random phylogenetic structure.

5.
Synthesis. As previously found for non‐successional communities, facilitation among distantly related lineages appeared to drive successional dynamics. However, subsequent competition reduced phylogenetic diversity during succession in this Mediterranean system, and some species disappeared from the community.
The evolution of facilitation and mutualism
Authors: Bronstein Judith L.
Published: October 2009

1.While the relationship between facilitation and competition has been explored extensively in recent years, there is also a natural link between facilitation and mutualism, as both are interspecific interactions that confer benefits. Yet, the relationship between these two interactions has been minimally explored.

2.Here, I explore parallels and differences between mutualism and facilitation. Five focal areas organize current research on mutualism evolution: trait evolution; the continuum from specialization to generalization; the evolutionary origins and maintenance of the interaction; co‐evolution of partners; and the prevalence and implications of cheating. These foci are also helpful for investigating how facilitation evolves, a much less explored issue.

3.Testable hypotheses regarding the evolution of facilitation include the following: selection should be stronger on traits of facilitated species than on traits of facilitators; facilitative interactions with mutualistic (++) and commensal (+0) outcomes should exhibit greater evolutionary stability than those with antagonistic (+−) outcomes; co‐evolution should be possible in mutualistic and antagonistic facilitation only; when co‐evolution occurs, it should produce a geographic mosaic of interaction outcomes; and antagonistic facilitation could lead to selection on facilitators to either escape or to tolerate the neighbours that benefit from them.

4.Synthesis. Three gaps in our knowledge currently impede progress on evolutionary questions surrounding facilitation. First, reciprocal effects are rarely investigated; facilitation might evolve like mutualism, commensalism or antagonism, depending on effects on the facilitator species. Secondly, the genetics of relevant traits are not yet well explored; the traits themselves are better known for facilitator species than for the facilitated, which are more likely to evolve in the context of the interaction. Finally, the fitness costs and benefits associated with facilitation have rarely been measured. Filling these gaps should permit rapid progress in understanding how facilitation arises, persists and evolves.
Facilitation research in marine systems: state of the art, emerging patterns and insights for future developments
Authors: Bulleri Fabio
Published: October 2009

1. Positive species interactions are increasingly recognized as important drivers of community structure and ecosystem functioning. Although the literature on facilitative interactions in terrestrial environments has been reviewed and emerging patterns have been synthesized, comparable attempts are lacking for the marine realm.

2. By means of a quantitative survey of the literature, I provide a critical summary of current knowledge on positive species interactions in marine environments. In particular, I (i) assess how marine facilitation research compares to that carried out in terrestrial environments in terms of focus and philosophical approach; (ii) illustrate the mechanisms by which facilitation takes place in different habitats; (iii) assess whether benefactor and beneficiary species are more likely to belong to the same or to a different trophic level; and (iv) provide examples of how including facilitation into ecological theory might advance our understanding of the mechanisms that regulate ecosystem functioning.

3. Except for some studies in intertidal habitats, few studies in marine environments have been framed within mainstream facilitation theory (e.g. the Stress Gradient Hypothesis) and research does not seem to be organized in a self‐contained theme. Amelioration of physical conditions appears to be the most common mechanism of facilitation in intertidal habitats, whilst associational defence predominates in the subtidal.

4. In contrast to the terrestrial literature, dominated by plant–plant interactions, marine benefactors and beneficiary species often belong to different trophic levels. This might imply little overlapping of resource niches or a differential response to environmental conditions or consumer pressure, with implications for the persistence of facilitative effects at the extreme ends of stress gradients.

5. Recent research shows that facilitation can enhance temporal variability and invasibility of marine communities and emphasizes the central role of positive species interactions in regulating the functioning of natural ecosystems.

6.
Synthesis. Studies encompassing a wide variety of life histories and environmental conditions are central to achieving a unified facilitation theory. Research in marine environments can provide new insights into the mechanisms underlying variations in the strength and direction of species interactions, but this will require greater awareness and consideration of facilitation.
The role of plant interactions in the restoration of degraded ecosystems: a meta‐analysis across life‐forms and ecosystems
Authors: Gómez‐Aparicio Lorena
Published: October 2009

1. Traditionally, techniques of plant manipulation during restoration have focused on the reduction of competition by ‘problematic’ existing vegetation. However, the increasing recognition of facilitation as a main process regulating the composition of communities has brought a change in the practice of restoration towards a better awareness of the benefits inherent to conserving neighbouring vegetation.

2. Here, I provide the results of a meta‐analysis of published studies that have manipulated interactions among plants with the objective of restoring degraded terrestrial systems. I created four different data sets corresponding to the variables most commonly used to measure plant performance (i.e. emergence, survival, growth and density), and asked whether the benefits of facilitation as a restoration tool vary depending on the study duration, the life‐form of the neighbour and target species, and the ecosystem type.

3. Neighbour effects varied strongly among performance estimators. Positive effects were frequently found for emergence and survival, whereas neutral or negative interactions predominated for growth and density.

4. No clear support existed for a relationship between study duration and neighbour effect.

5. The life‐form of the interacting species, particularly of neighbours, largely influenced the interaction outcome. Herbs had strong negative effects, especially on other herb species, whereas shrubs had large facilitative effects, especially on trees.

6. Semiarid and tropical systems showed in general more positive neighbour effects than wetlands and particularly mesic temperate systems, where negative interactions predominated. However, these results were largely influenced by the over‐representation of herb species in wetlands and temperate habitats, survival facilitation being found in all systems when only woody species were considered.

7. Synthesis.Pre‐existing vegetation can have large impacts on species establishment in degraded habitats. Inhibition predominates in herbaceous communities typical of early‐successional stages, whereas facilitation prevailes in communities dominated by shrubs and trees. Even productive systems (e.g. mesic temperate habitats) appear suitable for the application of facilitation as a restoration tool of woody communities. Whereas restoring herbaceous communities seems largely reliable on removal techniques, augmenting populations of nurse shrubs and trees should be considered a promising strategy for restoring woody late‐successional communities.
Facilitation in the conceptual melting pot
Authors: Brooker Rob W. , Callaway Ragan M.
Published: October 2009

1. Here we present an introduction to this issue’s Special Feature arising from the British Ecological Society Symposium: Facilitation in Plant Communities (20–22 April 2009).

2. Papers in the Special Feature demonstrate the benefits that arise from cross‐system application of general concepts, for example, the well‐known stress gradient hypothesis. Such comparisons challenge our definition of facilitation, as well as our pre‐conceptions on the nature of intermediary organisms.

3. We suggest that under some circumstances a clear definition of the two‐way nature of interactions is essential, e.g. when considering the evolutionary implications of facilitation. In other cases, however, we can perhaps be more relaxed, e.g. when facilitation is a component of conservation ecology.

4.
Synthesis. Overall we believe that establishing facilitation as an independent concept has driven substantial progress towards a clearer understanding of how ecological systems work. Through the links established by work such as that presented in this Special Feature, we believe this field will continue to make rapid progress and aid ecological understanding in general.
Cardiovascular outcomes and their relationships to lipoprotein components in patients with and without chronic kidney disease: results from the IDEAL trial
Authors: Holme I. , Fayyad R. , Faergeman O. , Kastelein J. J. P. , Olsson A. G. , Tikkanen M. J. , Larsen M. L. , Lindahl C. , Holdaas H. , Pedersen T. R. ,   On behalf of the Incremental Decrease in End Points Through Aggressive Lipid Lowering Study Group
Published: October 2009

Abstract.  Holme I, Fayyad R, Faergeman O, Kastelein JJP, Olsson AG, Tikkanen MJ, Larsen ML, Lindahl C, Holdaas H, Pedersen TR, On behalf of the Incremental Decrease in End Points Through Aggressive Lipid Lowering Study Group (Centre of Preventive Medicine, Oslo, Norway; Århus University Hospital, Århus, Denmark; Academic Hospital Amsterdam, Amsterdam, The Netherlands; University Hospital, Linköping, Sweden; Helsinki University Central Hospital, Helsinki, Finland; Oslo University Hospital, Rikshospitalet, Oslo, Norway; Pfizer Sweden, Sollentuna, Sweden; and Pfizer Inc., New York, NY, USA). Cardiovascular outcomes and their relationships to lipoprotein components in patients with and without chronic kidney disease: Results from the IDEAL trial. J Intern Med 2010; 267:567–575.

Objectives.  In Incremental Decrease in Endpoints through Aggressive Lipid‐lowering (IDEAL), we compared cardiovascular outcomes in patients with and without chronic kidney disease (CKD) (estimated glomerular filtration rate <60 mL min−1 1.73 m−2) and analysed relationships between lipoprotein components (LC) and major coronary events (MCE) and other cardiovascular (CV) events.

Design.  Exploratory analysis of CV endpoints in a randomized trial comparing high dose of atorvastatin to usual dose of simvastatin on MCE.

Settings.  Patients with CKD were compared with the non‐CKD patients. Cox regression models were used to study the relationships between on‐treatment levels of LC and incident MCE.

Findings.  Chronic kidney disease was strongly associated with cardiovascular end‐points including total mortality. In patients with CKD, a significant benefit of high dose atorvastatin treatment was found for any CV events, stroke and peripheral artery disease, but not for MCE. However, all cardiovascular end‐points except stroke and CV mortality were reduced in the non‐CKD group. Differential changes in LC or relationships to LC could not explain the different treatment outcomes in MCE in the two groups.

Interpretation.  Chronic kidney disease was a powerful risk factor for all cardiovascular end‐points. The reason why the significant reductions achieved by high‐dose statin treatment in most CV end‐points in the non‐CKD group were only in part matched by similar reductions in the CKD patients is not apparent. This difference did not result from differential changes in or relations to LC, but limited power may have increased the possibility of chance findings.
Successful antiviral therapy determines a significant decrease in squamous cell carcinoma antigen‐associated (SCCA) variants’ serum levels in anti‐HCV positive cirrhotic patients*
Authors: Giannini E. G. , Basso M. , Bazzica M. , Contini P. , Marenco S. , Savarino V. , Picciotto A.
Published: October 2009

Summary.  Aberrant squamous cell carcinoma antigen (SCCA) expression is an early event in hepatocarcinogenesis, and increasing serum levels of SCCA variants IgM immune complexes (SCCA‐IgM IC) have been found in cirrhotic patients developing hepatocellular carcinoma (HCC). We longitudinally evaluated a cohort of cirrhotic patients with hepatitis C virus infection (HCV) who underwent pegylated interferon (PEG‐IFN) and ribavirin treatment. SCCA‐IgM IC levels were assessed in the sera of 33 cirrhotic patients with HCV (21 males, median age 57 years) before, at the end and at 6‐month and 1‐year follow‐up after treatment with PEG‐IFN and ribavirin. SCCA‐IgM IC serum levels (arbitrary units/mL, AU/mL) were evaluated according to treatment outcome: sustained virological response (SVR) vs nonresponse (NR). Overall, 15 patients obtained a SVR to antiviral therapy (45%). There was no significant difference in baseline SCCA‐IgM IC serum levels between SVR and NR patients. When compared to baseline (451.2 AU/mL), SVR patients showed a significant decrease in median SCCA‐IgM IC serum levels at the end of treatment (186.8 AU/mL, P = 0.013) and at both 6‐month (96.8 AU/mL, P < 0.001) and 1‐year follow‐up (52.4 AU/mL, P < 0.001), while no significant modification was observed in NR patients. In patients with HCV‐related liver cirrhosis, successful antiviral therapy is associated with a dramatic and significant decrease in SCCA‐IC serum levels. Because of the pathophysiological correlation between SCCA and liver carcinogenesis, it is hypothesized that in patients with liver cirrhosis, SVR may be accompanied by a decreased proliferative stimulation.
Identifying glacial refugia in a geographic parthenogen using palaeoclimate modelling and phylogeography: the New Zealand stick insect Argosarchus horridus (White)
Authors: BUCKLEY THOMAS R. , MARSKE KATHARINE A. , ATTANAYAKE DILINI
Published: October 2009

We have used phylogeographic analysis of mitochondrial DNA (COI and COII genes) and ecological niche modelling (ENM) to reconstruct the population history of Argosarchus horridus (White), a widespread species of New Zealand stick insect. These data were used to address outstanding questions on the role of glacial refugia in determining the distribution and genetic structure of New Zealand species. Phylogeographic analysis shows a general pattern of high diversity in upper North Island and reduced diversity in lower North Island and South Island. The ENM indicates that during the last glacial maximum, A. horridus was largely restricted to refugia around coastal areas of North Island. The ENM also suggests refugia on the northeast coast of South Island and southeast coast of North Island and this prediction is verified by phylogeographic analysis, which shows a clade restricted to this region. Argosarchus horridus is also most likely a geographic parthenogen where males are much rarer at higher latitudes. The higher levels of genetic variation in northern, bisexual populations suggest southern and largely unisexual populations originated from southwardly expanding parthenogenetic lineages. Bayesian skyline analysis also provides support for a recent population size increase consistent with a large increase in geographic distribution in the late Pleistocene. These results exemplify the utility of integrating ENM and phylogeographic analysis in testing hypotheses on the origin of geographic parthenogenesis and effects of Pleistocene environmental change on biodiversity.
Breast feeding very‐low‐birthweight infants at discharge: a multicentre study using WHO definitions
Authors: Davanzo Riccardo , Ronfani Luca , Brovedani Pierpaolo , Demarini Sergio
Published: October 2009

Human milk has several advantages in the nutrition of very‐low‐birthweight (VLBW) infants. However, there are limited data on breast feeding (BF) in neonatal intensive care units (NICU). The aim of this study was to identify a practical definition of BF rate in VLBW infants and to test its applicability and reproducibility in Italian NICUs. The study population included all VLBW infants discharged from 12 level 3 NICUs, over a 12‐month period. Type of feeding was recorded according to the World Health Organisation (WHO) definition, with a 72‐h recall period.

We enrolled 594 VLBW infants. Mean birthweight was 1105 g (SD: 267), mean gestational age was 29.2 weeks (SD: 2.7) and mean length of stay in NICUs was 62.5 days (SD: 56.5). At discharge, 30.5% of VLBW infants were exclusively breast fed, 0.2% were predominantly breast fed, 23.8% were on complementary feeding and 45.5% were exclusively formula fed. A wide variability in BF rates was seen between centres. Among exclusively breast‐fed VLBW infants, only 10% sucked directly and exclusively at the breast. WHO definitions can be used to assess type of feeding at discharge from NICUs. We speculate that common feeding definitions may allow both comparisons among different NICUs and ratings of quality improvement programmes.
Relationships between birthweight and biomarkers of chronic disease in childhood: Aboriginal Birth Cohort Study 1987–2001
Authors: Sayers Susan , Singh Gurmeet , Mott Susan , McDonnell Joseph , Hoy Wendy
Published: October 2009

Reports of relationships between lower birthweight and later chronic diseases are mainly from populations with low rates of low birthweight (LBW) and growth‐restricted births. A prospective study of an Australian Aboriginal birth cohort with a mean birthweight of 3050 g (SD 630), 16% LBW and 28% fetal growth restriction was used to examine the relationships between birthweight and selected biomarkers of chronic adult disease.

At a mean age of 11.4 years (range 8.9–14), the mean weight was 35.7 kg (SD 11.8) and the mean height was 143.8 cm (SD 10.6). Using the Centers for Disease Control and Prevention (CDC) 2000 growth references, weight and height‐for‐age z‐scores were −0.8 (SD 1.4) and −0.5 (SD 1.07) respectively and using World Health Organisation criteria, 19% of children were classified as underweight (weight for age Z‐score <2.0). The relationships between birthweight and blood pressure (n = 475), total cholesterol (n = 461), Apolipoprotein A‐1 (n = 343), Apolipoprotein B (n = 390), respiratory function tests (n = 427), kidney size determined by ultrasound (n = 446), urinary albumin/creatinine ratio (n = 420) and fasting triglycerides (n = 281), insulin (n = 272) and glucose (n = 279) were examined using regression models adjusted for sex, gestational age, current age and puberty status. In this population with high rates of fetal growth restriction at birth and an excess of under‐nutrition at age 11 years we found that birthweight had a negative relationship with child blood pressure only, while current child weight was positively related to blood pressure, total cholesterol, Apolipoprotein B, respiratory function tests, kidney size, and fasting triglycerides, insulin and glucose.
Understanding the factors associated with differences in caesarean section rates at hospital level: the case of Latin America
Authors: Taljaard Monica , Donner Allan , Villar José , Wojdyla Daniel , Faundes Anibal , Zavaleta Nelly , Acosta Arnaldo
Published: October 2009

As in many other regions of the world, caesarean section (CS) rates in Latin America are increasing. Studies elsewhere have shown that providing feedback to caregivers regarding their own performance relative to their peers can significantly reduce the rates. Our objectives are to calculate risk‐adjusted CS rates for hospitals in Latin America and to identify factors associated with differences among risk‐adjusted rates. We included 120 randomly selected institutions in eight countries of Latin America, representing 97 095 pregnancies. We used random‐effects models to calculate a risk‐adjusted rate for each hospital and to identify hospitals significantly higher or lower than a benchmark rate. We conducted a regression analysis to identify characteristics of hospitals associated with differences among risk‐adjusted rates.

The overall CS rate was 35%, ranging from 0% to 85%. Risk‐adjusted CS rates ranged from 11% to 78%. Three‐quarters of hospitals had risk‐adjusted rates significantly above the previously identified benchmark of 20%. Characteristics of institutions explained 48% of the variability among risk‐adjusted rates, including being a private as opposed to a public institution, having some economic incentive for CS as opposed to no incentive, and having ≥50 maternity beds.

Strategies to halt further increases in CS rates and reduce rates to levels that reflect the best quality of care, are urgently needed worldwide. The involvement of local quality control departments is an essential component in achieving success. Our results can be used to identify institutions that can be targets for further interventions to reduce CS rates.
Basal metabolic rate and risk‐taking behaviour in birds
Authors: MØLLER A. P.
Published: October 2009

Basal metabolic rate (BMR) constitutes the minimal metabolic rate in the zone of thermo‐neutrality, where heat production is not elevated for temperature regulation. BMR thus constitutes the minimum metabolic rate that is required for maintenance. Interspecific variation in BMR in birds is correlated with food habits, climate, habitat, flight activity, torpor, altitude, and migration, although the selective forces involved in the evolution of these presumed adaptations are not always obvious. I suggest that BMR constitutes the minimum level required for maintenance, and that variation in this minimum level reflects the fitness costs and benefits in terms of ability to respond to selective agents like predators, implying that an elevated level of BMR is a cost of wariness towards predators. This hypothesis predicts a positive relationship between BMR and measures of risk taking such as flight initiation distance (FID) of individuals approached by a potential predator. Consistent with this suggestion, I show in a comparative analysis of 76 bird species that species with higher BMR for their body mass have longer FID when approached by a potential predator. This effect was independent of potentially confounding variables and similarity among species due to common phylogenetic descent. These results imply that BMR is positively related to risk‐taking behaviour, and that predation constitutes a neglected factor in the evolution of BMR.
Clinal variation in post‐winter male fertility retention; an adaptive overwintering strategy in Drosophila melanogaster
Authors: RAKO L. , POULSEN N. A. , SHIRRIFFS J. , HOFFMANN A. A.
Published: October 2009

In insects including Drosophila melanogaster, females can overwinter at the adult stage by adopting a shallow reproductive diapause, but almost nothing is known about male reproductive diapause. In this study, we test for the maintenance of fertility in overwintering males from the eastern Australian D. melanogaster cline. Males from southern temperate populations maintained in field cages in temperate Melbourne had a higher fertility in spring compared with males from tropical locations. Temperate males successfully inseminated more females, and there were also more offspring produced per inseminated female. The resulting linear post‐winter fertility clines were unrelated to male body size. In contrast, there was no clinal variation for fertility in nonoverwintering males held in the laboratory. The cline in overwintering male fertility is likely to have evolved as an adaptive response to latitudinal climatic variation over the last 100 years.