bluuebunny/crossref_metadata_2025_split huggingface dataset:
Natural strontium isotope composition as a tracer of weathering patterns and of exchangeable calcium sources in acid leached soils developed on loess of central Belgium
Authors: Drouet Th. , Herbauts J. , Gruber W. , Demaiffe D. 
Published: August 2006

SummaryThe natural Sr isotope composition of acid leached soils developed on loess, under beech forest, in central Belgium was used as a tracer of soil forming processes, in conjunction with physico‐chemical and quantitative mineralogical investigations. Attention was focused on weathering and exchange processes, with special emphasis on the origin of the current soil exchangeable fraction and the influence of the atmospheric deposition and biological cycling on the calcium exchangeable pool (Sr acts as a proxy for Ca). The determination of 87Sr/86Sr ratios was made on the bulk soil, on the clay‐ and silt‐size soil separates, on 0.1 m HCl extracts, on the labile pool, on the soil solution and on the bulk precipitation. The acid leached soil profiles are characterized by a sequence of weathering processes that is highlighted by both mineralogical and isotopic changes. From the calcareous unweathered loess (pH 7.5) to the uppermost soil horizons (pH < 4.0) the evolution of the 87Sr/86Sr isotope ratio clearly reflects: (i) the selective weathering of Ca‐plagioclase (small 87Sr/86Sr ratio) and the increasing proportion of resistant K‐ and Rb‐rich minerals (large 87Sr/86Sr ratio) in the uppermost soil horizons; and (ii) a downward translocation of clay minerals with a large isotopic ratio, a physical breakdown of muscovite and a non‐congruent chemical weathering of K‐feldspar. The influence of organic restitutions or atmospheric deposition is not significant. The comparison between the Sr isotopic signature of the soil solution, and the exchangeable and HCl‐extractible soil fractions provides information about cation exchange efficiency, soil–water interaction and the origin of the exchangeable pool.
Interactions between CD8αβ and the TCRαβ/CD3‐receptor Complex
Authors: Rubin B. , Riond J. , Leghait J. , Gairin J. E. 
Published: August 2006

AbstractCD8+ T cells recognize antigenic peptides bound to major histocompatibility complex (MHC) class I molecules on normal antigen‐presenting cells (APC), as well as on virus‐infected cells or tumour cells (pMHC). At least two receptor types participate in recognition of these complexes: T‐cell receptor (TCR) αβ heterodimers and CD8αβ molecules. The former molecules react with antigenic peptide and variable regions of MHC class I molecules, whereas the latter molecules react with constant α3 regions of MHC class I molecules. As the avidity of both receptor‐MHC interactions is low, it is believed that TCRαβ and CD8αβ heterodimers collaborate in T‐cell recognition. We have established a TCR/CD3–CD8 capture ELISA, which can measure the interaction of pMHC with CD8αβ molecules and with TCR/CD3 complexes. The major findings are: (1) TCR/CD3 complexes derived from in vitro activated T cells and captured by anti‐CD3 MoAb, do bind specific pMHC and (2) CD8+ T cells express at least three forms of CD8αβ molecules: single CD8αβ, CD3–CD8 and TCR/CD3–CD8 complexes. Only the latter complexes are associated with CD3ζ homodimers, and the quantity of TCR/CD3–CD8 complexes relative to total CD8αβ molecules appears to increase and to be selected into sucrose‐gradient microdomains as a function of TCRαβ‐mediated T‐cell activation.
Central and Peripheral RAG Protein Re‐expression: Underestimate Mechanisms of Tolerance?
Authors: Hillion S. , Rochas C. , Devauchelle V. , Youinou P. , Jamin C. 
Published: August 2006

AbstractThe generation of developing B cells in the bone marrow is regulated by recombination activating genes RAG1 and RAG2 proteins. They contribute to the synthesis of functional antibodies (Abs) that can present self‐reactivities following V(D)J (V, variable; D, diversity and J, joining) recombination. The emergence of autoreactive B cells is prevented by deletion through apoptosis, by stimulation blockade through anergy, or by synthesis of a new B‐cell receptor through receptor edition. In the periphery, somatic hypermutation during the course of germinal centre (GC) responses can lead to the appearance of autoreactive and low‐affinity Ab‐producing B cells. Apoptotic deletion and receptor revision regulate these autoreactive and inappropriate B cells. Moreover, the presence of RAG‐positive B cells outside GCs suggest that still uncharacterized regulation checkpoint, associated with secondary V(D)J recombination, also contribute to the regulation of autoreactivities. Failure in central and/or peripheral tolerance mechanisms associated with RAG expression could contribute to the terminal differentiation of autoreactive B cells leading to autoimmune states.
Tissue Homeostasis and Immunity – More on Models
Authors: Cunliffe J. 
Published: August 2006

AbstractThis article continues the ongoing debate around models of the immune system. Earlier contributors have paid much attention to the various processes that lead to adaptive immune system aggression or tolerance. They have often based their discussions around facts that have been established by experimental investigation. However, both the observation and interpretation of these facts have been influenced by the function – or system goal – that is believed to have generated them. The perception of this function (of all or part of the immune system) is influenced by long established theories in immunology (e.g. horror autotoxicus, clonal deletion in utero, pathogen elimination, clonal selection, auto‐immunity and so on) which, for many, have become enshrined as facts. One function that has had less consideration and has not been extensively investigated is the maintenance of tissue homeostasis. When the immune system is viewed from this perspective, the facts invite alternative interpretations. Whilst this perspective may not necessarily be the only valid one, let alone a correct one, viewing things this way – at least briefly – might help to expose hidden assumptions. It also emphasizes that the immune system is a system and, as such, it can by analysed through the principles of general systems theory.
Vaccine Approaches to Prevent Tuberculosis
Authors: Wiker H. G. , Mustafa T. , Målen H. , Riise A. M. D. 
Published: August 2006

Abstract Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), is one of the main killers among infectious pathogens in the world and represents an important factor that sustain poverty in developing countries. Failure of the BCG vaccine to protect in endemic regions, and increasing problems with multi‐drug‐resistant TB calls for development of better vaccines to prevent reactivation of tuberculosis. It has been estimated that an effective post‐exposure vaccine will prevent 30–40% of the TB cases. New vaccines should also prevent development of TB in HIV‐infected individuals. Recent characterization of M. tuberculosis H37Rv by proteomic methods has revealed a large number of novel secreted proteins that should be investigated in mouse models for latent and slowly progressive TB. There is an important balance between control of infection and tissue destruction in TB, and M. tuberculosis has developed strategies to prevent immune‐mediated sterilization. Central to this strategy is inhibition of apoptosis of macrophages. Development of novel vaccines should therefore take into consideration the effects on central markers to obtain a better picture of regulation of immunity, including FasL and Bcl‐2 which are essential in regulation of apoptosis.
Antibody‐Mediated Regulation of the Immune Response
Authors: Hjelm F. , Carlsson F. , Getahun A. , Heyman B. 
Published: August 2006

AbstractAntibodies administered in vivo together with the antigen they are specific for can regulate the immune response to that antigen. This phenomenon is called antibody‐mediated feedback regulation and has been known for over 100 years. Both passively administered and actively produced antibodies exert immunoregulatory functions. Feedback regulation can be either positive or negative, resulting in >1000‐fold enhancement or >99% suppression of the specific antibody response. Usually, the response to the entire antigen is up‐ or downregulated, regardless of which epitope the regulating antibody recognizes. IgG of all isotypes can suppress responses to large particulate antigens like erythrocytes, a phenomenon used clinically in Rhesus prophylaxis. IgG suppression works in mice lacking the known Fc‐γ receptors (FcγR) and a likely mechanism of action is epitope masking. IgG1, IgG2a and IgG2b administered together with soluble protein antigens will enhance antibody and CD4+ T‐cell responses via activating FcγR, probably via increased antigen presentation by dendritic cells. IgG3 as well as IgM also enhance antibody responses but their effects are dependent on their ability to activate complement. A possible mechanism is increased B‐cell activation caused by immune complexes co‐crosslinking the B‐cell receptor with the complement‐receptor 2/CD19 receptor complex, known to lower the threshold for B‐cell activation. IgE‐antibodies enhance antibody and CD4+ T‐cell responses to small soluble proteins. This effect is entirely dependent on the low‐affinity receptor for IgE, CD23, the mechanism probably being increased antigen presentation by CD23+ B cells.
Detection of Autoantibodies to the BTB‐kelch Protein KLHL7 in Cancer Sera
Authors: Bredholt G. , Storstein A. , Haugen M. , Krossnes B. K. , Husebye E. , Knappskog P. , Vedeler C. A. 
Published: August 2006

AbstractThe aim of the study was to search for novel targets of autoantibodies in patients with paraneoplastic neurological syndromes (PNS). PNS are mediated by immune reactions against autoantigen(s) shared by the cancer cells and the nervous system. By serological screening of a rat cerebellum cDNA expression library using anti‐Hu‐positive sera from three patients with paraneoplastic encephalomyelitis (PEM), we identified an open reading frame encoding an isoform of the BTB‐kelch protein KLHL7. Immunohistochemical studies demonstrated that the KLHL7 protein is expressed in the nuclei of neurones, but not in other tissues including various cancers. However, the KLHL7 protein was detected in the nuclei of cancer cell lines. Antibodies to KLHL7 were detected by an immunoprecipitation assay in sera from 12 of 254 (4.7%) patients with various cancers and 2 of 170 blood donors (1.2%). None of 50 sera from patients with multiple sclerosis were positive for KLHL7 antibodies. Sixteen patients with classical PNS and anti‐Hu or anti‐Yo antibodies were also negative for KLHL7 antibodies. Seven cancer patients with KLHL7 antibodies had various signs of neurological disease that could be related to cancer, whereas the remaining five seropositive cancer patients had no clinical signs of possible PNS. The present results indicate that KLHL7 antibodies are associated with various cancers, and in some patients also with neurological disease. Whether KLHL7 antibodies can be used as paraneoplastic markers for PNS remains to be determined.
The diversity and origin of exotic ants arriving in New Zealand via human‐mediated dispersal
Authors: Ward Darren F. , Beggs Jacqueline R. , Clout Mick N. , Harris Richard J. , O’Connor Simon 
Published: August 2006

ABSTRACTThe number of exotic ant species being dispersed to new regions by human transportation and the trade pathways responsible for this are poorly understood. In this study, the taxonomic diversity, trade pathways, and origin of exotic ants intercepted at the New Zealand border were examined for the period 1955–2005. Overall, there were a total 4355 interception records, with 115 species from 52 genera. The 10 most frequently intercepted genera, and the 20 most frequently intercepted species contributed > 90% of all records. Many of the species frequently intercepted are regarded as invasive species, and several are established in New Zealand. The most intercepted species was Pheidole megacephala. Despite a relatively low trade relationship, a high proportion (> 64%) of the exotic ants which were intercepted originated from the Pacific region. However, the majority of species intercepted from the Pacific was exotic to the region (71%), or to a lesser extent, wide‐ranging Pacific native species. No endemic species from the Pacific were intercepted. The effectiveness of detecting exotic ant species at the New Zealand border ranged from 48–78% for different trade pathways, indicating a number of species remain undetected. Trade routes associated with specific geographical regions represent a major filter for the arrival of exotic ant species. Despite the importance of the Pacific as a frequent pathway, we suggest that the future establishment of exotic ant species in New Zealand is likely to be mitigated by a renewed focus on trade routes with cool temperate regions, particularly Australia.
Invasion by the amphipod Gammarus pulex alters community composition of native freshwater macroinvertebrates
Authors: Kelly David W. , Bailey Roberta J. , MacNeil Calum , Dick Jaimie T. A. , McDonald Robbie A. 
Published: August 2006

ABSTRACTAssessing the effects of invading species on native community structure is often confounded by environmental factors and weakened by lack of replicated, long‐term pre‐ and post‐invasion monitoring. Here, we uncouple the community effects of a freshwater amphipod invader from environmental differences. In Irish rivers, the introduced Gammarus pulex replaces the native Gammarus duebeni celticus. However, the River Lissan in Northern Ireland is dissected by a weir that has slowed the upstream invasion by G. pulex. This allowed us in 2000 to sample three contiguous 150‐m reaches that were (1) G. pulex dominated; (2) mixed Gammarus spp.; and (3) G. duebeni celticus only. In 2003, we resampled these reaches and one additional of mixed Gammarus species and one with only G. duebeni celticus further upstream. In temperature, conductivity, and pH, there were statistically significant but no biologically relevant differences among the five reaches of 2003, and between the three reaches surveyed in both years. Although there was evidence of recovery in macroinvertebrate diversity and richness in invaded reaches between years, continued upstream invasion was associated with sustained reductions in these community metrics as compared to un‐invaded sites. Community ordination indicated (1) different associations of community composition attributed to the distribution, abundance, and biomass of the invader; and (2) increasing similarity of invaded communities over time. The impact mechanisms of G. pulex on macroinvertebrate community composition may include predation and competition. The consequences of the observed community changes for ecosystem functioning require further investigation.
Transplantation of ocular tissue from a donor with sporadic Creutzfeldt–Jakob disease
Authors: Tullo Andrew B , Buckley Roger J , Kelly Tom , Head Mark W , Bennett Peter , Armitage W John , Ironside James W 
Published: August 2006

AbstractBackground:  One definite, one probable and several possible transmissions of sporadic Creutzfeldt–Jakob disease (sCJD) have followed corneal transplantation. We report an incident in the UK in 1997 in which both corneas and scleras from a donor, subsequently confirmed to have had sCJD, were transplanted. The final clinical outcome for two surviving recipients is still not yet known.Case report:  In 1997, a 56‐year‐old woman died from biopsy‐proven carcinoma of the bronchus. Both eyes were donated for transplantation. Shortly before she died, she had developed neurological symptoms thought to be due to brain metastases. However, the final result of a neurological post‐mortem examination revealed evidence of sCJD. By this time the corneas had been transplanted, one 3 months previously into a 40‐year‐old man for keratoconus and the other 4 months previously into an 85‐year‐old woman for Fuchs’ dystrophy. In addition, both scleras had been transplanted into a 36‐year‐old man undergoing oculoplastic reconstructive surgery. The surgeons and patients were informed and removal of tissue was advised but undertaken in only two of the patients. Immunohistochemistry failed to demonstrate the presence of the abnormal form of the prion protein in explanted tissue.Conclusions:  Eight years after the event, two patients remain free of symptoms suggestive of iatrogenic CJD (http://www.cjd.ed.ac.uk/criteria.htm). The third having died aged 92 years, some 7 years after surgery, showing signs of dementia not considered indicative of iatrogenic CJD. Nevertheless this adverse incident attracted substantial publicity. Coupled with continuing concerns in the UK about person‐to‐person transmission of variant CJD, this has lead to a number of important consequences in donor eye retrieval, ocular tissue banking and transplantation.
Iris colour, optic disc dimensions, degree and progression of glaucomatous optic nerve damage
Authors: Jonas Jost B , Budde Wido M , Stroux Andrea , Oberacher‐Velten Isabel M 
Published: August 2006

AbstractPurpose:  To evaluate whether iris colour influences size and shape of the optic nerve head and risk for glaucoma progression.Methods:  The hospital‐based observational study included 1973 eyes of 1012 Caucasian subjects with ocular hypertension or chronic open‐angle glaucoma. For all patients, colour stereo optic disc photographs were evaluated, and corneal pachymetry and achromatic perimetry were performed. Main outcome measures were optic nerve head parameters, the development or progression of visual field defects and iris colour.Results:  In most of the study groups, size of the optic disc, neuroretinal rim, alpha zone and beta zone of parapapillary atrophy, retinal vessel diameter and central corneal thickness did not differ significantly between eyes with blue, green, brown and mixed iris colour. In the normal‐pressure glaucoma group, neuroretinal rim area was smallest in the population with mixed‐coloured eyes and largest in the group of eyes with brown irides (P = 0.001 after correction for inter‐eye dependency and multiple testing). For the ocular hypertensive subjects and glaucoma patients with follow‐up examinations, the rate of development or progression of glaucomatous visual field loss was not significantly associated with iris colour (P = 0.060).Conclusions:  In Caucasian subjects, iris colour does not have a major association with the size of the optic nerve head structures, central corneal thickness and retinal arterial diameter. In Caucasian patients with ocular hypertension or chronic open‐angle glaucoma, an influence of iris colour on the risk for development or progression of glaucomatous visual field defects could not be confirmed.
Study of osteoporosis awareness, investigation and treatment of patients discharged from a tertiary public teaching hospital
Authors: Inderjeeth C. A. , Glennon D. , Petta A. 
Published: August 2006

AbstractBackground: Patients with fragility fractures secondary to osteoporosis are at risk of recurrent fracture. Osteoporosis is often underrecognized and undertreated. We looked at the levels of awareness, investigation and treatment of patients with fracture.Methods: The study group included patients admitted to a tertiary teaching hospital. Postal surveys were sent to female patients over 60 years of age who had been identified in the hospital database as having International Classification of Diseases‐10 codes for fracture and discharged between June 1997 and January 2002. The questionnaire had specific questions on the histories of the fractures, the risk factors, the awareness of osteoporosis, bone mineral density testing and the treatment for osteoporosis.Results: Of 1584 surveys posted, 366 valid questionnaires were returned. The median age of respondents was 81 years with a range of 60–99 years. Fifty‐nine per cent reported one fracture, 41% two or more fractures and 65% reported a hip fracture. Forty‐eight per cent of patients were aware that they had osteoporosis and 35% reported having a bone density performed. Thirty‐seven per cent reported being on treatment for osteoporosis on discharge, with the majority being on treatment with calcium (34%).Conclusion: This postal survey of a high‐risk patient group discharged from a tertiary hospital confirm the findings from other population‐based and hospital‐based studies that a significant proportion of patients at risk of further fracture are not investigated or offered specific treatment for osteoporosis. Lack of awareness of underlying osteoporosis by both treating clinicians and patients is likely to be a major contributing factor.
Mobilising modern facts: health technology assessment and the politics of evidence
Authors: May Carl 
Published: August 2006

AbstractConventional models of ‘evidence’ for clinical practice focus on the role of randomised controlled clinical trials and systematic reviews as technologies that promote a specific model of rigour and analytic accountability. The assumption that runs through the disciplinary field of health technology assessment (HTA), for example, is that the quantification of evidence about cost and clinical effectiveness is central to rational policy‐making and healthcare provision. But what are the conditions in which such knowledge is mediated into decision‐making contexts, and how is it understood and used when it gets there? This paper addresses these questions by examining a series of meetings and seminars attended by senior clinical researchers, social care and health service managers in the UK between 1998–2004, and sessions of the House of Commons Health Committee held in 2001 and 2005. These provide contexts in which questions about the value and utility of evidence produced within the frame of HTA were explored in relation to parallel questions about the design, evaluation and implementation of telemedicine and telecare systems. The paper points to the ways that evidence generated in the normative frame of HTA was increasingly seen as one‐dimensional and medicalised knowledge that failed to respond to the contingencies of everyday practice in health and social care settings.
In search of fair trade: ethical consumer decision making in France
Authors: Ozcaglar‐Toulouse Nil , Shiu Edward , Shaw Deirdre 
Published: August 2006

AbstractWhile the market for fair trade products has been growing in many countries, this paper examines the French market where fair trade remains marginal but is experiencing growth. Using a modified Theory of Planned Behaviour framework the research examines consumer intention to purchase fair trade grocery products in order to explain the pertinent decision‐making criteria of both consumers of and potential consumers of fair trade. Results reveal that concerned consumers should not be treated as one homogeneous group, rather, the distinct variations in the factors that influence their decision making must be considered when promoting, labelling and distributing fair trade products. Implications for both sustaining and developing the market for fair trade products in the future are highlighted and discussed.