bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maternal allergy influences the proliferation of neonatal T cells expressing CCR4, CXCR5 or CD103
Authors: Haddeland U. , Brandtzaeg P. , Nakstad B. 
Published: May 2007

SummaryBackground
Elevated proliferative response to allergen in cord blood mononuclear cells (CBMCs) is related to subsequent allergy development of the neonate and has been suggested as a screening marker for high allergy risk.Objective
To characterize the proliferating cells in CBMCs from a neonatal group influenced by maternal allergy compared with a control group without known allergic heredity.Methods
CBMCs were stimulated with bovine β‐lactoglobulin (β‐LG) and proliferation was analysed by radioactive thymidine incorporation and expressed both as the traditional stimulation index (SI) and SI corrected by eliminating non‐specific proliferation. After β‐LG combined with endotoxin stimulation, cellular expression of IL‐4 and IFN‐γ mRNA was determined by quantitative RT‐PCR and adhesion as well as chemokine receptors were analysed by three‐colour flow cytometry in proliferating T cells (CD3+Ki‐67+).Results
The percentage of CCR4+ cells correlated weakly with concurrent IL‐4 expression (rS=0.5, P<0.05), while CXCR3 correlated strongly with IFN‐γ expression (rS=0.83, P<0.001). In the allergy risk group, the percentage of proliferating T cells expressing CCR4 or integrin αE (CD103) was significantly reduced compared with the control group, while CXCR5 and the corrected SI were relatively increased (CCR4: P=0.01; integrin αE: P=0.03; CXCR5: P=0.04; SI: P=0.04).Conclusion
Our results implied delayed maturation of immune functions involved in cellular migration, cell–cell interaction and immunoregulatory functions in neonates with hereditary allergy risk. The alterations observed in this subject group suggested that the corrected SI as well as proliferation of CCR4+, CXCR5+ or CD103+ T cells in allergen‐stimulated CBMCs might serve as early screening markers for allergy risk.
Allergic rhinitis and asthma comorbidity: ARIA classification of rhinitis does not correlate with the prevalence of asthma
Authors: Antonicelli L. , Micucci C. , Voltolini S. , Feliziani V. , Senna G. E. , Di Blasi P. , Visonà G. , De Marco R. , Bonifazi F. 
Published: May 2007

SummaryBackground
Allergic rhinitis and asthma comorbidity is supported by both the similar underlying pathogenesis and immunologic mechanisms. The aim of this study was to verify whether the characteristics of rhinitis classified according to the new Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines correlate with the prevalence of asthma.Methods
From 1 March to 30 June 2002, a multi‐centre cross‐sectional study was conducted by 154 allergists chosen from throughout Italy. Duration, severity of rhinitis (according to the ARIA classification) and the type of allergic sensitizations were compared with the prevalence of asthma.Results
One thousand three hundred and twenty‐one consecutive rhinitis‐allergic patients aged 18 years or older were enrolled for the study. The majority of patients, 1060 (80.24%), were on medication at the time of their specialist visit. Mild intermittent rhinitis was diagnosed in 7.7% of patients, moderate/severe intermittent in 17.1%, mild persistent in 11.6%, and moderate/severe persistent in 63.6%. The prevalence of asthma was 48% in patients with mild intermittent rhinitis, 49.6% in moderate–severe intermittent rhinitis, 36.6% in mild persistent rhinitis and 47.5% in moderate severe persistent patients. No correlation between the ARIA categories of rhinitis and the prevalence of asthma was found.A multivariate analysis, after adjustment for age, sex, type of sensitization, level of severity and duration of rhinitis classified according to the ARIA guidelines, demonstrated that age, over 41 years [risk ratio (RR) 1.260, 95% confidence interval (CI) 1.072–1.482] and especially over 51 years (RR 1.460, 95% CI 1.237–1.723), sensitization to indoor allergens (mite and cat), (RR 1.203, 95% CI 1.060–1.366), and polysensitization (RR 1.178, 95% CI 1.004–1.383) are significant risk factors for asthma.Conclusion
In allergic rhinitis (AR) patients referred to a specialist, the features of AR as defined by the ARIA classification are not able to predict the presence of asthma, therefore all such patients should be assessed for asthma.
Effect of tecastemizole on pulmonary and cutaneous allergic inflammatory responses
Authors: Lever R. , Hefni A. , Moffatt J. D. , Paul W. , Page C. P. 
Published: May 2007

SummaryBackground
Tecastemizole, a major metabolite of astemizole, is a potent and selective H1 receptor antagonist. Evidence suggests that this and certain other H1 receptor antagonists may possess anti‐inflammatory effects that are, in some cases, independent of H1 receptor antagonism.Objective
The aim of this study was to investigate the anti‐inflammatory effects of tectastemizole in models of allergic inflammation.Methods
Effects of tecastemizole were assessed in a murine model of allergic lung inflammation, in passive cutaneous anaphylaxis (PCA) responses in guinea‐pig skin and in in vitro assays measuring endothelial adhesion molecule expression and leucocyte–endothelial adhesion.Results
Tecastemizole inhibited antigen‐induced eosinophil recruitment to the lungs of allergic mice in a dose‐dependent manner. Furthermore, combination of a sub‐effective dose of tecastemizole, combined with a sub‐effective dose of dexamethasone inhibited eosinophil accumulation in this model. Plasma extravasation in PCA reactions was inhibited by tecastemizole, although by a mechanism that would appear to be H1 receptor‐dependent. Cytokine‐induced endothelial intercellular adhesion molecule‐1 and vascular cell adhesion molecule‐1 expression, as well as mononuclear cell adhesion to human umbilical vein endothelial cells was inhibited by tecastemazole in a manner independent of H1 receptor antagonism.Conclusion
These data suggest that tecastemizole may have H1 receptor‐independent effects in inhibiting late‐phase inflammatory responses, while acute responses appear to be inhibited in a H1 receptor‐dependent manner. Furthermore, our data suggest an important potential steroid‐sparing role for such drugs in the treatment of allergic inflammatory conditions.
A prospective study of allergy development in 158 children and 128 adults with new extensive exposure to furred animals
Authors: Millqvist E. , Johansson Å. , Månsson T. , Bende M. 
Published: May 2007

SummaryBackground
There is still controversy over whether exposure to furred animals increases or decreases the risk of developing sensitization and allergic symptoms to such animals, and there is a need for further knowledge on this subject.Objective
The aim of this study was to follow allergy development in relation to new extensive exposure to furred animals in adults and children.Methods
A total of 286 individuals, 128 parents and 158 children, were recruited from 68 families who intended to buy a dog or a cat, or where one child of the family intended to start riding a horse. Subjects were examined before the new allergen exposure and once a year thereafter for 5 years, in all at six occasions, and they also completed questionnaires covering allergy symptoms. Serum IgE antibodies to cat, dog and horse were determined each year, and fur allergens from beds and living rooms were analysed.Results
Two‐hundred and fifty‐six study subjects remained for evaluation, 37 of whom showed signs of allergic sensitization at the start of the study. Four children (11%) in this pre‐sensitized group developed IgE antibodies to their new animal and six (16%) to another animal. Among the 219 participants who were not sensitized when entering the study, one male adult (0.4%) developed a sensitization to his new animal, and nobody developed sensitization to other animals. Pre‐sensitized individuals had significantly more allergic symptoms at the study start, but the symptom scores did not change over time.Conclusions
When the first year of a human's life has passed, we have no strong evidence to recommend avoidance of a domestic animal in order to prevent new allergy development, even if there are known allergies in the family or if the individual is sensitized and has allergic symptoms to another allergen. Five years exposure to new fur allergens does not seem to influence sensitization to these animals in either sensitized or non‐sensitized children and adults.
Assembly rules of ground‐foraging ant assemblages are contingent on disturbance, habitat and spatial scale
Authors: Sanders Nathan J. , Gotelli Nicholas J. , Wittman Sarah E. , Ratchford Jaime S. , Ellison Aaron M. , Jules Erik S. 
Published: May 2007

AbstractAim  A major endeavour of community ecology is documenting non‐random patterns in the composition and body size of coexisting species, and inferring the processes, or assembly rules, that may have given rise to the observed patterns. Such assembly rules include species sorting resulting from interspecific competition, aggregation at patchily distributed resources, and co‐evolutionary dynamics. However, for any given taxon, relatively little is known about how these patterns and processes change through time and vary with habitat type, disturbance history, and spatial scale. Here, we tested for non‐random patterns of species co‐occurrence and body size in assemblages of ground‐foraging ants and asked whether those patterns varied with habitat type, disturbance history, and spatial scale.Location  Burned and unburned forests and fens in the Siskiyou Mountains of southern Oregon and northern California, USA.Methods  We describe ground‐foraging ant assemblages sampled over two years in two discrete habitat types, namely Darlingtonia fens and upland forests. Half of these sites had been subject to a large‐scale, discrete disturbance – a major fire – in the year prior to our first sample. We used null model analyses to compare observed species co‐occurrence patterns and body‐size distributions in these assemblages with randomly generated assemblages unstructured by competition both within (i.e. at a local spatial scale) and among (i.e. at a regional scale) sites.Results  At local spatial scales, species co‐occurrence patterns and body‐size ratios did not differ from randomness. At regional scales, co‐occurrence patterns were random or aggregated, and there was evidence for constant body‐size ratios of forest ants. Although these patterns varied between habitats and years, they did not differ between burned and unburned sites.Main conclusions  Our results suggest that the operation of assembly rules depends on spatial scale and habitat type, but that it was not affected by disturbance history from fire.
Molecular and palaeoecological evidence for multiple glacial refugia for evergreen oaks on the Iberian Peninsula
Authors: López de Heredia U. , Carrión J. S. , Jiménez P. , Collada C. , Gil L. 
Published: May 2007

AbstractAim  A multiple glacial refugia hypothesis for Mediterranean plant species was tested with the evergreen Quercus complex (Quercus suber L., Quercus ilex L. and Quercus coccifera L.) from the Iberian Peninsula, using molecular and palaeobotanical data.Location  The Iberian Peninsula, which is an ecologically and physiographically complex area located on the western edge of the Mediterranean Basin.Methods  We sampled 1522 individuals from 164 populations of Q. suber, Q. ilex and Q. coccifera. A review of the recent literature on fossil pollen and charcoal records and a nested clade analysis on chloroplast DNA polymerase chain reaction‐restriction fragment length polymorphism was carried out to infer demographic and historical processes.Results  The analysis indicates at least one glacial refugium for Q. suber in south‐western Iberia. Extensive introgression of Q. suber with Q. ilex indicates several potential refugia in eastern Iberia. Past fragmentation was followed by a restricted range flow/range expansion, suggesting multiple refugia for Q. ilex–Q. coccifera elsewhere in central and northern Iberia and multiple areas of secondary contact. This finding is consistent with fossil records.Main conclusions  The predicted multiple refugia during glacial periods indicates the existence of secondary post‐glaciation contact areas. These areas contained complex diversity patterns resulting mainly from range expansions followed by isolation by distance. To a lesser degree, traces of restricted and long‐distance dispersal were also found.
Life on the rocks
Authors: Gorbushina Anna A. 
Published: May 2007

SummaryBiofilms are interface micro‐habitats formed by microbes that differ markedly from those of the ambient environment. The term ‘subaerial biofilm’ (SAB) was coined for microbial communities that develop on solid mineral surfaces exposed to the atmosphere. Subaerial biofilms are ubiquitous, self‐sufficient, miniature microbial ecosystems that are found on buildings, bare rocks in deserts, mountains, and at all latitudes where direct contact with the atmosphere and solar radiation occurs. Subaerial biofilms on exposed terrestrial surfaces are characterized by patchy growth that is dominated by associations of fungi, algae, cyanobacteria and heterotrophic bacteria. Inherent subaerial settlers include specialized actinobacteria (e.g. Geodermatophilus), cyanobacteria and microcolonial fungi. Individuals within SAB communities avoid sexual reproduction, but cooperate extensively with one another especially to avoid loss of energy and nutrients. Subaerial biofilm metabolic activity centres on retention of water, protecting the cells from fluctuating environmental conditions and solar radiation as well as prolonging their vegetative life. Atmospheric aerosols, gases and propagatory particles serve as sources of nutrients and inoculum for these open communities. Subaerial biofilms induce chemical and physical changes to rock materials, and they penetrate the mineral substrate contributing to rock and mineral decay, which manifests itself as bio‐weathering of rock surfaces. Given their characteristic slow and sensitive growth, SAB may also serve as bioindicators of atmospheric and/or climate change.
Morphological transformation in a freshwater Cyanobium sp. induced by grazers
Authors: Jezberová Jitka , Komárková Jaroslava 
Published: May 2007

SummaryWe document a remarkable morphological transformation, attributable to grazing by nanoflagellate Ochromonas sp. DS, of a phycocyanin‐rich freshwater Cyanobium sp. (10‐NR 98.2% similar 16S rRNA gene sequence to the type species Cyanobium gracile). The single cells aggregated into microcolonies (average size 40 μm) in the presence of the protist. Colonies were characterized by hundreds of tubes (spinae), 100 nm to 1 μm long and 63 ± 6 nm wide, on the surfaces of the Cyanobium cells co‐cultured with Ochromonas. Spinae production, previously unknown for the freshwater Cyanobium species, suggests that picocyanobacterial life strategies are more flexible than previously thought.
Ultrastructural and electron energy‐loss spectroscopic analysis of an extracellular filamentous matrix of an environmental bacterial isolate
Authors: Böckelmann Uta , Lünsdorf Heinrich , Szewzyk Ulrich 
Published: May 2007

SummaryStrain F8, a bacterial isolate from ‘river snow’, was found to produce extracellular fibres in the form of a filamentous network. These extracellular filaments, which were previously shown to be composed of DNA, have been studied for the first time by ultrastructural and electron energy‐loss spectroscopy in the present work. ‘Whole mount’ preparations of strain F8 indicate these polymers are ultrastructurally homogeneous and form a network of elemental filaments, which have a width of 1.8–2.0 nm. When incubated at pH 3.5 with colloidal cationic ThO2 tracers they become intensely stained (electron dense), affording direct evidence that the fibres are negatively charged and thus acidic chemically. Elemental analysis of the extracellular filaments by Energy‐filtered Transmission Electron Microscopy revealed phosphorus to be the main element present and, because pretreatment of F8 cells with DNase prevented thorium labelling, the fibres must be composed of extracellular DNA (eDNA). Neither ultrathin sections nor ‘whole mount negative stain’ caused DNA release by general cell lysis. Additionally, cells infected with phages were never observed in ultrathin sections and phage particles were never detected in whole mount samples, which rules out the possibility of phages being directly involved in eDNA release.
Calcium buffering systems and calcium signaling in aged rat basal forebrain neurons
Authors: Murchison David , Griffith William H. 
Published: May 2007

SummaryDisturbances of neuronal Ca2+ homeostasis are considered to be important determinants of age‐related cognitive impairment. Cholinergic neurons of the basal forebrain (BF) are principal targets of decline associated with aging and dementia. During the last several years, we have attempted to link these concepts in a rat model of ‘normal’ aging. In this review, we will describe some changes that we have observed in Ca2+ signaling of aged BF neurons and the reversal of one of these changes by dietary caloric restriction. Our evidence supports a scenario in which subtle changes in the properties of voltage‐gated Ca2+ channels result in increased Ca2+ influx during aging. This increased Ca2+, in turn, triggers an increase in rapid Ca2+ buffering in the somatic compartment of aged BF neurons. However, this nominal ‘compensation’, along with other changes in Ca2+ handling machinery (notably mitochondria) alters the Ca2+ signal with age in a way that is dependent on the magnitude of the Ca2+ load. By combining whole‐cell patch clamp electrophysiology, ratiometric Ca2+‐sensitive microfluorimetry and single‐cell reverse transcription‐polymerase chain reaction, we have determined that age‐related rapid buffering changes are present in identified cholinergic BF neurons and that these changes can be prevented by a caloric restriction dietary regimen. Because caloric restriction extends lifespan and retards the progression of age‐related dysfunction, these findings suggest that increased Ca2+ buffering in cholinergic neurons may be relevant to cognitive decline during normal aging. Importantly, calcium homeostatic mechanisms of BF cholinergic neurons are amenable to dietary interventions that could promote cognitive health during aging.
Oxidative stress and aberrant signaling in aging and cognitive decline
Authors: Dröge Wulf , Schipper Hyman M. 
Published: May 2007

SummaryBrain aging is associated with a progressive imbalance between antioxidant defenses and intracellular concentrations of reactive oxygen species (ROS) as exemplified by increases in products of lipid peroxidation, protein oxidation, and DNA oxidation. Oxidative conditions cause not only structural damage but also changes in the set points of redox‐sensitive signaling processes including the insulin receptor signaling pathway. In the absence of insulin, the otherwise low insulin receptor signaling is strongly enhanced by oxidative conditions. Autophagic proteolysis and sirtuin activity, in turn, are downregulated by the insulin signaling pathway, and impaired autophagic activity has been associated with neurodegeneration. In genetic studies, impairment of insulin receptor signaling causes spectacular lifespan extension in nematodes, fruit flies, and mice. The predicted effects of age‐related oxidative stress on sirtuins and autophagic activity and the corresponding effects of antioxidants remain to be tested experimentally. However, several correlates of aging have been shown to be ameliorated by antioxidants. Oxidative damage to mitochondrial DNA and the electron transport chain, perturbations in brain iron and calcium homeostasis, and changes in plasma cysteine homeostasis may altogether represent causes and consequences of increased oxidative stress. Aging and cognitive decline thus appear to involve changes at multiple nodes within a complex regulatory network.
The importance of being subtle: small changes in calcium homeostasis control cognitive decline in normal aging
Authors: Toescu Emil C. , Verkhratsky Alexei 
Published: May 2007

SummaryAging is a complex, multifactorial process. One of the features of normal aging of the brain is a decline in cognitive functions and much experimental attention has been devoted to understanding this process. Evidence accumulated in the last decade indicates that such functional changes are not due to gross morphological alterations, but to subtle functional modification of synaptic connectivity and intracellular signalling and metabolism. Such synaptic modifications are compatible with a normal level of activity and allow the maintenance of a certain degree of functional reserve. This is in contrast to the changes in various neurodegenerative diseases, characterized by significant neuronal loss and dramatic and irreversible functional deficit. This whole special issue has been initiated with the intention of focusing on the processes of normal brain aging. In this review, we present data that shows how subtle changes in Ca2+ homeostasis or in the state of various Ca2+‐dependent processes or molecules, which occur in aging can have significant functional consequences.
Alterations in intrinsic neuronal excitability during normal aging
Authors: Disterhoft John F. , Oh M. Matthew 
Published: May 2007

SummaryNormal aging subjects, including humans, have difficulty learning hippocampus‐dependent tasks. For example, at least 50% of normal aging rabbits and rats fail to meet a learning criterion in trace eyeblink conditioning. Many factors may contribute to this age‐related learning impairment. An important cause is the reduced intrinsic excitability observed in hippocampal pyramidal neurons from normal aging subjects, as reflected by an enlarged postburst afterhyperpolarization (AHP) and an increased spike‐frequency adaptation (accommodation). In this review, we will focus on the alterations in the AHP and accommodation during learning and normal aging. We propose that age‐related increases in the postburst AHP and accommodation in hippocampal pyramidal neurons play an integral role in the learning impairment observed in normal aging subjects.