bluuebunny/crossref_metadata_2025_split huggingface dataset:
Common human Toll‐like receptor 9 polymorphisms and haplotypes: association with atopy and functional relevance
Authors: Berghöfer B. , Frommer T. , König I. R. , Ziegler A. , Chakraborty T. , Bein G. , Hackstein H. 
Published: September 2005

SummaryBackground
Toll‐like receptor 9 (TLR9) is a pattern‐recognition receptor that detects unmethylated CpG motifs prevalent in bacterial and viral DNA. TLR9 stimulation is a key event after bacterial infection, triggering innate immunity and T‐helper type 1 skewed adaptive immunity. Synthetic CpG‐oligodeoxynucleotides (CpG‐ODNs) represent a promising and novel class of immune adjuvants for allergy treatment, vaccination, and cancer therapy. However, common functional TLR9 gene variants could interfere with the clinical utilization of CpG‐ODN in immunotherapy. Recently, a possible association of TLR9 polymorphism C‐1237T with asthma has been reported.Objective
The aim of the present study was to investigate whether TLR9 polymorphisms or haplotypes have functional relevance and are associated with atopy.Methods
We genotyped five common TLR9 single‐nucleotide polymorphisms (SNPs) in promoter, exon, and intron regions of the gene in 527 healthy blood donors, and estimated four common haplotypes. The total IgE and specific IgE levels against the most common aeroallergens were measured (n=303). IFN‐α production by plasmacytoid dendritic cells (pDCs) was analysed after stimulation with TLR9 ligand CpG‐ODN (n=220).Results
No significant influence of common TLR9 polymorphisms and haplotypes on the total and specific IgE levels was found. Functional analysis of CpG‐ODN‐induced IFN‐α did not indicate a significant role for common TLR9 gene polymorphisms in TLR9 function.Conclusion
We conclude that common genetic differences in the TLR9 gene exert no major influence on allergy susceptibility, and are unlikely to have on impact on clinical application of CpG‐ODNs.
Environmental risk factors and allergic bronchial asthma
Authors: D'Amato G. , Liccardi G. , D'Amato M. , Holgate S. 
Published: September 2005

SummaryThe prevalence of allergic respiratory diseases such as bronchial asthma has increased in recent years, especially in industrialized countries. A change in the genetic predisposition is an unlikely cause of the increase in allergic diseases because genetic changes in a population require several generations. Consequently, this increase may be explained by changes in environmental factors, including indoor and outdoor air pollution. Over the past two decades, there has been increasing interest in studies of air pollution and its effects on human health. Although the role played by outdoor pollutants in allergic sensitization of the airways has yet to be clarified, a body of evidence suggests that urbanization, with its high levels of vehicle emissions, and a westernized lifestyle are linked to the rising frequency of respiratory allergic diseases observed in most industrialized countries, and there is considerable evidence that asthmatic persons are at increased risk of developing asthma exacerbations with exposure to ozone, nitrogen dioxide, sulphur dioxide and inhalable particulate matter. However, it is not easy to evaluate the impact of air pollution on the timing of asthma exacerbations and on the prevalence of asthma in general. As concentrations of airborne allergens and air pollutants are frequently increased contemporaneously, an enhanced IgE‐mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of allergic respiratory allergy and bronchial asthma. Pollinosis is frequently used to study the interrelationship between air pollution and respiratory allergy. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc) can affect both components (biological and chemical) of this interaction. By attaching to the surface of pollen grains and of plant‐derived particles of paucimicronic size, pollutants could modify not only the morphology of these antigen‐carrying agents but also their allergenic potential. In addition, by inducing airway inflammation, which increases airway permeability, pollutants overcome the mucosal barrier and could be able to ‘prime’ allergen‐induced responses. There are also observations that a thunderstorm occurring during pollen season can induce severe asthma attacks in pollinosis patients. After rupture by thunderstorm, pollen grains may release part of their cytoplasmic content, including inhalable, allergen‐carrying paucimicronic particles.
Population dynamics of the exploited sea cucumber Isostichopus fuscus in the western Galápagos Islands, Ecuador
Authors: HEARN ALEX , MARTÍNEZ PRISCILLA , VERONICA TORAL‐GRANDA M. , MURILLO JUAN CARLOS , POLOVINA JEFFREY 
Published: September 2005

AbstractLong‐term density data for the sea cucumber, Isostichopus fuscus, from Canal Bolivar (separating western Isabela and eastern Fernandina Islands), Galápagos, were compared with catch statistics and used in a stock depletion model to determine the extent of the effects of the fishery on the existing population and the potential for the population to recover after each fishing season. Recruitment indices were found to be low from 1994 until mid‐1999, when a mass recruitment event was registered and numbers of small individuals increased dramatically. The increase in density of juveniles peaked in 2001 and has declined since. Recruitment in this species of sea cucumber appears to be highly sporadic and may depend on intense climatic events such as the warm El Niño. Current levels of fishing activity are unsustainable. The management implications of pulse recruitment in this fishery are discussed.
Response of fish and plankton to nutrient loading reduction in eight shallow Danish lakes with special emphasis on seasonal dynamics
Authors: JEPPESEN ERIK , JENSEN JENS PEDER , SØNDERGAARD MARTIN , LAURIDSEN TORBEN L. 
Published: September 2005

Summary1. For 13 years the response of the plankton and fish community to a decline in external phosphorus loading was studied in eight lakes with a mean depth <5 m. We conducted chi‐square analyses of sign of slope (positive or negative) of bimonthly averages of plankton variables for the eight lakes versus time. For fish, we compared results from two periods, i.e. 1989–1994 versus 1994–2001 as less data were available.2. Fish community structure tended to respond to the lowered concentration of total phosphorus (TP), although not all changes were significant. While catch per unit effort (multi‐mesh sized gill nets) of cyprinids (especially bream, Abramis brama and roach, Rutilus rutilus) was highest in the first 5‐year period, the quantitative importance particularly of perch (Perca fluviatilis), pike (Esox lucius) and rudd (Scardinius erythropthalmus), a littoral species, increased significantly after 1994.3. No changes occurred in zooplankton biomass, except for an increase in November and December. Biomass of small cladocerans, however, declined during summer and autumn, and the proportion of Daphnia to cladoceran biomass also increased. Average body weight of Daphnia and that of all cladocerans increased. The proportion of calanoids among copepods decreased in summer and the average body weight of cyclopoids and calanoids decreased during summer and autumn/early winter.4. Total biovolume of phytoplankton declined significantly in March to June and tended to decline in November and December as well, while no significant changes were observed during summer and autumn. Non‐heterocystous cyanobacteria showed a decreasing trend during summer and autumn, while heterocystous cyanobacteria increased significantly in late summer. An increase in late summer was also evident for cryptophytes and chrysophytes, while diatoms tended to decline during most seasons.5. We conclude that phytoplankton, and probably also fish, responded rapidly to reduced loading, whereas the effect on zooplankton was less pronounced. However, increases in body weight of cladocerans and the zooplankton to phytoplankton biomass ratio during summer indicate reduced top‐down control on zooplankton and enhanced grazing on phytoplankton. This conclusion is supported by a tendency for fish biomass to decline and a shift towards greater dominance by piscivores and, thus, an increased likelihood of predator control of zooplanktivorous cyprinids.
Combining palaeolimnological and limnological approaches in assessing lake ecosystem response to nutrient reduction
Authors: BATTARBEE RICHARD W. , JOHN ANDERSON N. , JEPPESEN ERIK , LEAVITT PETER R. 
Published: September 2005

Summary1. Palaeolimnological data and limnological time‐series data are highly complementary. Sediment records extend time‐scales, integrate subannual variability and expand the range of sites that can be studied, but they suffer from taphonomic biases and occasionally from uncertain chronology. Observational time‐series data, on the other hand, are highly resolved but are very limited in extent both in space and time.2. Palaeolimnological and observational data‐sets need to be combined in oligotrophication research to establish (i) the past and present status of lakes needed to identify reference conditions; (ii) changes in ecosystem state; (iii) responses to nutrient reduction; and (iv) the potential role of other factors (e.g. additional stressors, climate change) that might confound predictions of future state.
A comparison of diatom phosphorus transfer functions and export coefficient models as tools for reconstructing lake nutrient histories
Authors: BENNION HELEN , JOHNES PENNY , FERRIER ROBERT , PHILLIPS GEOFF , HAWORTH ELIZABETH 
Published: September 2005

Summary1. We compared the baseline phosphorus (P) concentrations inferred by diatom‐P transfer functions and export coefficient models at 62 lakes in Great Britain to assess whether the techniques produce similar estimates of historical nutrient status.2. There was a strong linear relationship between the two sets of values over the whole total P (TP) gradient (2–200 μg TP L−1). However, a systematic bias was observed with the diatom model producing the higher values in 46 lakes (of which values differed by more than 10 μg TP L−1 in 21). The export coefficient model gave the higher values in 10 lakes (of which the values differed by more than 10 μg TP L−1 in only 4).3. The difference between baseline and present‐day TP concentrations was calculated to compare the extent of eutrophication inferred by the two sets of model output. There was generally poor agreement between the amounts of change estimated by the two approaches. The discrepancy in both the baseline values and the degree of change inferred by the models was greatest in the shallow and more productive sites.4. Both approaches were applied to two lakes in the English Lake District where long‐term P data exist, to assess how well the models track measured P concentrations since approximately 1850. There was good agreement between the pre‐enrichment TP concentrations generated by the models. The diatom model paralleled the steeper rise in maximum soluble reactive P (SRP) more closely than the gradual increase in annual mean TP in both lakes. The export coefficient model produced a closer fit to observed annual mean TP concentrations for both sites, tracking the changes in total external nutrient loading.5. A combined approach is recommended, with the diatom model employed to reflect the nature and timing of the in‐lake response to changes in nutrient loading, and the export coefficient model used to establish the origins and extent of changes in the external load and to assess potential reduction in loading under different management scenarios.6. However, caution must be exercised when applying these models to shallow lakes where the export coefficient model TP estimate will not include internal P loading from lake sediments and where the diatom TP inferences may over‐estimate TP concentrations because of the high abundance of benthic taxa, many of which are poor indicators of trophic state.
Long‐term response of a shallow, moderately flushed lake to reduced external phosphorus and nitrogen loading
Authors: KÖHLER J. , HILT S. , ADRIAN R. , NICKLISCH A. , KOZERSKI H. P. , WALZ N. 
Published: September 2005

Summary1. The responses of nutrient concentrations, plankton, macrophytes and macrozoobenthos to a reduction in external nutrient loading and to contemporary climatic change were studied in the shallow, moderately flushed Lake Müggelsee (Berlin, Germany). Weekly to biweekly data from 1979 to 2003 were compared with less frequently collected historical data.2. A reduction of more than 50% in both total phosphorus (TP) and total nitrogen (TN) loading from the hypertrophic (1979–90) to the eutrophic period (1997–2003) was followed by an immediate decline in TN concentrations in the lake. TP concentrations only declined during winter and spring. During summer, phosphorus (P) release from the sediments was favoured by a drastic reduction in nitrate import. Therefore, Müggelsee acted as a net P source for 6 years after the external load reduction despite a mean water retention time of only 0.1–0.16 years.3. Because of the likely limitation by P in spring and nitrogen (N) in summer, phytoplankton biovolume declined immediately after nutrient loading was reduced. The formerly dominant cyanobacteria (Oscillatoriales) Limnothrix redekei and Planktothrix agardhii disappeared, but the mean biovolume of the N2‐fixing species Aphanizomenon flos‐aquae remained constant.4. The abundance of Daphnia spp. in summer decreased by half, while that of cyclopoid copepod species increased. Abundances of benthic macroinvertebrates (mainly chironomids) decreased by about 80%. A resource control of both phytoplankton and zooplankton is indicated by significant positive correlations between nutrient concentrations and phytoplankton biovolume and between phytoplankton and zooplankton biomass.5. Water transparency in spring increased after nutrient reduction and resulted in re‐colonisation of the lake by Potamogeton pectinatus. However, this process was severely hampered by periphyton shading and grazing by waterfowl and fish.6. Water temperatures in Müggelsee have increased in winter, early spring and summer since 1979. The earlier development of the phytoplankton spring bloom was associated with shorter periods with ice cover, while direct temperature effects were responsible for the earlier development of the daphnid maximum in spring.
The recovery of a very shallow eutrophic lake, 20 years after the control of effluent derived phosphorus
Authors: PHILLIPS GEOFF , KELLY ANDREA , PITT JO‐ANNE , SANDERSON RORY , TAYLOR ELIOT 
Published: September 2005

Summary1. Monitoring at fortnightly to monthly intervals of a very shallow, lowland lake over 24 years has enabled the time course of recovery from nutrient enrichment to be investigated after high external P loading of the lake (>10 g P m−2 year−1) was reduced between 1977 and 1980.2. The lake showed a relatively rapid response during the spring and early summer, with a reduction in phytoplankton biomass occurring after 5 years when soluble reactive phosphorus concentration was <10 μg L−1.3. However, during the later summer the response was delayed for 15 years because of sustained remobilisation of phosphorus from the sediment. The greater water clarity in spring and a gradual shift from planktonic to benthic algal growth may be related to the reduction in internal loading after 15 years.4. Changes in the phytoplankton community composition were also observed. Centric diatoms became less dominant in the spring, and the summer cyanobacteria populations originally dominated by non‐heterocystous species (Limnothrix/Planktothrix spp.) almost disappeared. Heterocystous species (Anabaena spp. and Aphanizomenon flos‐aquae) were slower to decline, but after 20 years the phytoplankton community was no longer dominated by cyanobacteria.5. There were no substantial changes in food web structure following re‐oligotrophication. Total zooplankton biomass decreased but body size of Daphnia hyalina, the largest zooplankton species in the lake, remained unchanged, suggesting that the fish population remained dominated by planktivorous species.6. Macrophyte growth was still largely absent after 20 years, although during the spring water clarity may have become sufficient for macrophytes to re‐establish.
Response of a eutrophic, shallow subtropical lake to reduced nutrient loading
Authors: COVENEY M. F. , LOWE E. F. , BATTOE L. E. , MARZOLF E. R. , CONROW R. 
Published: September 2005

Summary1. Lake Apopka (FL, U.S.A.) was subjected to decades of high nutrient loading from farms developed in the 1940s on converted riparian wetlands. Consequences included perennially high densities of cyanobacteria, low water transparency, elimination of submerged vegetation, modified fish community, and deposition of nutrient‐rich, flocculent sediments.2. Initial steps were taken to reduce phosphorus (P) loading. Through strengthened regulation and purchase of farms for restoration, external P loading was reduced on average from 0.56 to 0.25 g P m−2 year−1 (55%) starting in 1993. The P loading target for the lake is 0.13 g P m−2 year−1.3. For the first 6 years of P loading reduction the annual sedimentation coefficient (σ) averaged 13% less than the prior long‐term value (0.97 versus 1.11 year−1). The sedimentation coefficient, σ, was lower in the last 3 years of the study, but this period included extreme low‐water conditions and may not be representative. Annual σ was negative (net P flux to the water column) only 1 year.4. Wind velocity explained 43% of the variation in σ during the period before reductions in total phosphorus (TP) concentration of lake water, but this proportion dropped to 6% after TP reductions.5. Annual mean TP concentrations differed considerably from values predicted from external loading and hydraulic retention time using the Vollenweider–Organization for Economic Co‐operation and Development relationship. Reductions in lake water TP concentration fit model predictions better when multiyear (3‐year) mean values were used.6. Evidence available to date indicates that this shallow, eutrophic lake responded to the decrease in external P loading. Neither recycling of sediment P nor wind‐driven resuspension of sediments prevented improvements in water quality. Reductions in TP concentration were evident about two TP‐resident times (2 × 0.9 year) after programmes began to reduce P loading. Improvements in concentrations of chlorophyll a and total suspended solids as well as in Secchi transparency lagged changes in lake‐water TP concentration but reached similar magnitudes during the study.
Island biogeography of the Mediterranean sea: the species–area relationship for terrestrial isopods
Authors: Gentile Gabriele , Argano Roberto 
Published: September 2005

AbstractAim  We looked at the biogeographical patterns of Oniscidean fauna from the small islands of the Mediterranean Sea in order to investigate the species–area relationship and to test for area‐range effects.Location  The Mediterranean Sea.Methods  We compiled from the literature a data set of 176 species of Oniscidea (terrestrial isopods) distributed over 124 Mediterranean islands. Jaccard's index was used as input for a UPGMA cluster analysis. The species–area relationship was investigated by applying linear, semi‐logarithmic, logarithmic and sigmoid models. We also investigated a possible ‘small island effect’ (SIE) by performing breakpoint regression. We used a cumulative and a sliding‐window approach to evaluate scale‐dependent area‐range effects on the log S/log A regression parameters.Results  Based on similarity indexes, results indicated that small islands of the Mediterranean Sea can be divided into two major groups: eastern and western. In general, islands from eastern archipelagos were linked together at similarity values higher than those observed for western Mediterranean islands. This is consistent with a more even distribution of species in the eastern Mediterranean islands. Separate archipelagos in the western Mediterranean could be discriminated, with the exception of islets, which tended to group together at the lowest similarity values regardless of the archipelago to which they belong. Islets were characterized by a few common species with large ranges. The species–area logarithmic model did not always provide the best fit. Most continental archipelagos showed very similar intercepts, higher than the intercept for the Canary island oceanic archipelago. Sigmoid regression returned convex curves. Evidence for a SIE was found, whereas area‐range effects that are dependent on larger scale analyses were not unambiguously supported.Main conclusions  The Oniscidea fauna from small islands of the Mediterranean Sea is highly structured, with major and minor geographical patterns being identifiable. Some but not all of the biogeographical complexity can be explained by interpreting the different shapes of species–area curves. Despite its flexibility, the sigmoid model tested did not always provide the best fit. Moreover, when the model did provide a good fit the curves looked convex, not sigmoid. We found evidence for a SIE, and minor support for scale‐dependent area‐range effects.
Gene diversity in a fragmented population of Briza media: grassland continuity in a landscape context
Authors: PRENTICE HONOR C. , LÖNN MIKAEL , ROSQUIST GABRIELLE , IHSE MARGARETA , KINDSTRÖM MERIT 
Published: September 2005

Summary

We investigated patterns of allozyme variation in demes of the grass Briza media in semi‐natural grassland fragments within a mosaic agricultural landscape on the Baltic island of Öland. In the study area, Briza is both a characteristic species of old pastures and an early colonizer of young grasslands developing on previously forested or arable sites.
Generalized linear models revealed that descriptors of both present landscape structure and past grassland history are significant determinants of genetic variation in the Briza demes. Genetic structure and levels of within‐deme diversity are influenced by the size of grassland fragments, the type of habitat surrounding the grasslands, the size/spatial extent of the demes, the geographic position of the demes and the historical continuity of the grassland fragments.
Gene diversity (H) was higher in demes from grassland polygons with a high proportion of adjacent grassland, higher in the more extensive demes, and decreased northwards within the study area.
The negative association between the inbreeding coefficient (FIS) and grassland continuity is interpreted in terms of a two‐stage colonization process: recruitment into young grasslands leads initially to spatial patchiness, but subsequent selection in maturing pastures occurs within an increasingly uniform and dense sward.
Despite a weak overall genetic structure (as indicated by Bayesian cluster analysis) the between‐deme FST was significant. Linear discriminant analysis of within‐deme allele frequencies grouped the demes according to the age and previous land‐use history of their grassland polygons. The convergence of the allele frequency profiles in the younger grasslands towards those of the old grasslands is consistent with convergence of selective regimes as pastures mature towards an increasingly uniform, dense sward and characteristic species assemblage.
The genetic composition of demes of a grassland species appears to be influenced by the process of plant community convergence during grassland development – complementing the recent finding that convergence of species composition in experimental assemblages of grassland plants is dependent on the genotypic composition of the component species.