bluuebunny/crossref_metadata_2025_split huggingface dataset:
Composition and dispersal of riverine and lake phytoplankton communities in connected systems with different water retention times
Authors: BERGSTRÖM ANN‐KRISTIN , BIGLER CHRISTIAN , STENSDOTTER ULRIKA , LINDSTRÖM EVA S. 
Published: August 2008

Summary1. Lake phytoplankton community structure may be influenced by both internal factors (predation, competition, resource constraints) and external ones, such as dispersal of materials and cells between connected habitats. However, little is known about the importance of cell dispersal for phytoplankton community structure in lakes.2. We investigated the abundance and dispersal of phytoplankton cells between connected rivers and lakes, and analysed whether similarities in phytoplankton community composition between rivers and lakes were primarily related to cell import rates or to characteristics of the local habitat. We focused on lakes along a gradient of theoretical water retention times (TWRT). Two data sets from Swedish lakes were used; a seasonal study of two connected boreal forest lakes, differing in TWRT, and a multi‐lake study of 13 lakes with a continuous range of TWRTs.3. Phytoplankton cells were transported and dispersed in all investigated rivers. In the seasonal study, cell import rates and similarities in phytoplankton community composition between the lake and its inlet(s) were much higher in the lake with a shorter TWRT. Phytoplankton community structure in different habitats was associated with total organic carbon (TOC). This indicates that local habitat characteristics may be important in determining lake phytoplankton community composition, even in the presence of substantial cell import.4. The multi‐lake study also showed a negative relationship between TWRT and similarities in phytoplankton community composition between inlets and lakes. Moreover, similarity in community structure was related to both cell import rates from inlet to lake and differences in habitat characteristics between inlet and lake. However, the variable most strongly correlated with community structure was TOC, indicating that species sorting rather than a mass effect was the most important mechanism underlying the correlation between community structure and retention time.5. Overall, our data suggest that local habitat characteristics may play a key role in determining community similarity in this set of lakes covering a large range of habitat connectedness. Due to the strong co‐variations between cell dispersal and TOC, it was hard to unequivocally disentangle the different mechanisms; hence, there is a need for further studies of the role of dispersal for phytoplankton community structures.
Soluble CD38 significantly prolongs the lifespan of memory B‐cell responses
Authors: Liu Xue Q. , Hart Derek N. J. , MacPherson Gordon G. , Good Michael F. , Wykes Michelle N. 
Published: August 2008

SummaryThe development and maintenance of memory B cells (MBC) is dependent on germinal centres (GC) with follicular dendritic cell (FDC) networks. We have previously shown that FDC networks within GC of the spleen express a novel ligand for CD38 and that the administration of soluble CD38 induces an expansion of these cellular structures. We therefore used adoptive transfer studies to investigate whether the expansion of FDC networks with soluble CD38 affected the generation and maintenance of antigen‐specific MBC. These studies found that the administration of soluble CD38 significantly extended the period after which MBC could be activated and that the frequencies of these cells also were increased. In conclusion, soluble CD38 appears to significantly extend the lifespan of antibody memory by increasing the numbers of MBC.
Peering into large lectures: examining peer and expert mark agreement using peerScholar, an online peer assessment tool
Authors: Paré D.E. , Joordens S. 
Published: August 2008

AbstractAs class sizes increase, methods of assessments shift from costly traditional approaches (e.g. expert‐graded writing assignments) to more economic and logistically feasible methods (e.g. multiple‐choice testing, computer‐automated scoring, or peer assessment). While each method of assessment has its merits, it is peer assessment in particular, especially when made available online through a Web‐based interface (e.g. our peerScholar system), that has the potential to allow a reintegration of open‐ended writing assignments in any size class – and in a manner that is pedagogically superior to traditional approaches. Many benefits are associated with peer assessment, but it was the concerns that prompted two experimental studies (n = 120 in each) using peerScholar to examine mark agreement between and within groups of expert (graduate teaching assistants) and peer (undergraduate students) markers. Overall, using peerScholar accomplished the goal of returning writing into a large class, while producing grades similar in level and rank order as those provided by expert graders, especially when a grade accountability feature was used.
‘The devil lay upon her and held her down’ Hypnagogic hallucinations and sleep paralysis described by the Dutch physician Isbrand van Diemerbroeck (1609–1674) in 1664
Authors: KOMPANJE E. J. O. 
Published: August 2008

SummaryHypnagogic and hypnopompic hallucinations are visual, tactile, auditory or other sensory events, usually brief but sometimes prolonged, that occur at the transition from wakefulness to sleep (hypnagogic) or from sleep to wakefulness (hypnopompic). Hypnagogic and hypnopompic hallucinations are often associated with sleep paralysis. Sleep paralysis occurs immediately prior to falling asleep (hypnagogic paralysis) or upon waking (hypnopompic paralysis). In 1664, the Dutch physician Isbrand Van Diemerbroeck (1609–1674) published a collection of case histories. One history with the title ‘Of the Night‐Mare’ describes the nightly experiences of the 50‐year‐old woman. This case report is subject of this article. The experiences in this case could without doubt be diagnosed as sleep paralysis accompanied by hypnagogic hallucinations. This case from 1664 should be cited as the earliest detailed account of sleep paralysis associated with hypnagogic illusions and as the first observation that sleep paralysis and hypnagogic experiences occur more often in supine position of the body.
No effect of 8‐week time in bed restriction on glucose tolerance in older long sleepers
Authors: ZIELINSKI MARK R. , KLINE CHRISTOPHER E. , KRIPKE DANIEL F. , BOGAN RICHARD K. , YOUNGSTEDT SHAWN D. 
Published: August 2008

SummaryThe aim of this study was to investigate the effects of 8 weeks of moderate restriction of time in bed (TIB) on glucose tolerance and insulin sensitivity in healthy older self‐reported long sleepers. Forty‐two older adults (ages 50–70 years) who reported average sleep durations of ≥8.5 h per night were assessed. Following a 2‐week baseline, participants were randomly assigned to two 8‐week treatments: either (i) TIB restriction (n = 22), which involved following a fixed sleep schedule in which time in bed was reduced by 90 min compared with baseline; (ii) a control (n = 18), which involved following a fixed sleep schedule but no imposed change of TIB. Sleep was monitored continuously via wrist actigraphy recordings, supplemented with a daily diary. Glucose tolerance and insulin sensitivity were assessed before and following the treatments. Compared with the control treatment, TIB restriction resulted in a significantly greater reduction of nocturnal TIB (1.39 ± 0.40 h versus 0.14 ± 0.26 h), nocturnal total sleep time (TST) (1.03 ± 0.53 h versus 0.40 ± 0.42 h), and 24‐h TST (1.03 ± 0.53 h versus 0.33 ± 0.43 h) from baseline values. However, no significant effect of TIB restriction was found for glucose tolerance or insulin sensitivity. These results suggest that healthy older long sleepers can tolerate 8 weeks of moderate TIB restriction without impairments in glucose tolerance or insulin sensitivity.
Transcriptional regulation by an NAC (NAM–ATAF1,2–CUC2) transcription factor attenuates ABA signalling for efficient basal defence towardsBlumeria graminisf. sp.hordeiin Arabidopsis
Authors: Jensen Michael K. , Hagedorn Peter H. , De Torres‐Zabala Marta , Grant Murray R. , Rung Jesper H. , Collinge David B. , Lyngkjaer Michael F. 
Published: August 2008

SummaryATAF1is a member of a largely uncharacterized plant‐specific gene family encoding NAC transcription factors, and is induced in response to various abiotic and biotic stimuli inArabidopsis thaliana. Previously, we showed that a mutant allele ofATAF1compromises penetration resistance in Arabidopsis with respect to the non‐host biotrophic pathogenBlumeria graminisf. sp.hordei(Bgh). In this study, we have used genome‐wide transcript profiling to characterize signalling perturbations inataf1plants followingBghinoculation. Comparative transcriptomic analyses identified an over‐representation of abscisic acid (ABA)‐responsive genes, including the ABA biosynthesis geneAAO3, which is significantly induced inataf1plants compared to wild‐type plants following inoculation withBgh. Additionally, we show thatBghinoculation results in decreased endogenous ABA levels in anATAF1‐dependent manner, and that the ABA biosynthetic mutantaao3showed increased penetration resistance toBghcompared to wild‐type plants. Furthermore, we show thatataf1plants show ABA‐hyposensitive phenotypes during seedling development and germination. Our data support a negative correlation between ABA levels and penetration resistance, and identify ATAF1 as a new stimuli‐dependent attenuator of ABA signalling for the mediation of efficient penetration resistance in Arabidopsis uponBghattack.
A semi‐dominant mutation in the ribosomal protein L10 gene suppresses the dwarf phenotype of the acl5 mutant in Arabidopsis thaliana
Authors: Imai Akihiro , Komura Mio , Kawano Eri , Kuwashiro Yoshitaka , Takahashi Taku 
Published: August 2008

SummaryDisruption of the Arabidopsis thaliana ACAULIS5 (ACL5) gene, which has recently been shown to encode thermospermine synthase, results in a severe dwarf phenotype. A previous study showed that sac51‐d, a dominant suppressor mutant of acl5‐1, has a premature termination codon in an upstream open reading frame (ORF) of SAC51, which encodes a putative transcription factor, and suggested the involvement of upstream ORF‐mediated translational control in ACL5‐dependent stem elongation. Here we report the identification of a gene responsible for sac52‐d, another semi‐dominant suppressor mutant of acl5‐1. SAC52 encodes ribosomal protein L10 (RPL10A), which is highly conserved among eukaryotes and implicated in translational regulation. Transformation of acl5‐1 mutants with a genomic fragment containing the sac52‐d allele rescued the dwarf phenotype of acl5‐1. GUS reporter activity under the control of a SAC51 promoter with its upstream ORF was higher in acl5‐1 sac52‐d than in acl5‐1, suggesting that suppression of the acl5‐1 phenotype by sac52‐d is attributable, in part, to enhanced translation of certain transcripts including SAC51. We also found that a T‐DNA insertion allele of SAC52/RPL10A causes lethality in the female gametophyte.
AGAMOUS‐LIKE24 and SHORT VEGETATIVE PHASE determine floral meristem identity in Arabidopsis
Authors: Gregis Veronica , Sessa Alice , Colombo Lucia , Kater Martin M. 
Published: August 2008

SummaryThe formation of flowers starts when floral meristems develop on the flanks of the inflorescence meristem. In Arabidopsis the identity of floral meristems is promoted and maintained by APETALA1 (AP1) and CAULIFLOWER (CAL). In the ap1 cal double mutant the meristems that develop on the flanks of the inflorescence meristem are unable to establish floral meristem identity and develop as inflorescence meristems on which new inflorescence meristems subsequently proliferate. We demonstrate in contrast to previous models that AGAMOUS‐LIKE 24 (AGL24) and SHORT VEGETATIVE PHASE (SVP) are also floral meristem identity genes since the ap1‐10 agl24‐2 svp‐41 triple mutant continuously produces inflorescence meristems in place of flowers. Furthermore, our results explain how AP1 switches from a floral meristem identity factor to a component that controls floral organ identity.
The airway smooth muscle CCR3/CCL11 axis is inhibited by mast cells
Authors: Saunders R. , Sutcliffe A. , Woodman L. , Kaur D. , Siddiqui S. , Okayama Y. , Wardlaw A. , Bradding P. , Brightling C. 
Published: August 2008

Background:  Airway smooth muscle hyperplasia is a feature of asthma, and increases with disease severity. CCR3‐mediated recruitment of airway smooth muscle progenitors towards the airway smooth muscle bundle has been proposed as one possible mechanism involved in airway smooth muscle hyperplasia. Mast cells are microlocalized to the airway smooth muscle bundle and whether mast cells influence CCR3‐mediated migration is uncertain.Methods:  We examined the expression of CCR3 by primary cultures of airway smooth muscle cells from asthmatics and nonasthmatics. CCR3 function was examined using intracellular calcium measurements, chemotaxis, wound healing, cell proliferation and survival assays. We investigated the recovery and function of both recombinant and airway smooth muscle‐derived CCL11 (eotaxin) after co‐culture with β‐tryptase and human lung mast cells.Results:  Airway smooth muscle expressed CCR3. Airway smooth muscle CCR3 activation by CCL11 mediated intracellular calcium elevation, concentration‐dependent migration and wound healing, but had no effect on proliferation or survival. Co‐culture with β‐tryptase or mast cells degraded recombinant and airway smooth muscle‐derived CCL11, and β‐tryptase inhibited CCL11‐mediated airway smooth muscle migration.Conclusions:  CCL11 mediates airway smooth muscle migration. However co‐culture with β‐tryptase or mast cells degraded recombinant and airway smooth muscle‐derived CCL11 and inhibited CCL11‐mediated airway smooth muscle migration. Therefore these findings cast doubt on the importance of the CCL11/CCR3 axis in the development of airway smooth muscle hyperplasia in asthma.
Evidence for an asthma risk locus on chromosome Xp: a replication linkage study
Authors: Brasch‐Andersen C. , Møller M. U. , Haagerup A. , Vestbo J. , Kruse T. A. 
Published: August 2008

Background:  Asthma is a complex genetic disorder characterized by chronic inflammation in the airways. Identification of genetic risk factors for asthma has been complicated due to genetic heterogeneity and influence from environmental risk factors. Despite the fact that multiple genetic linkage studies have been carried out the results are still conflicting and call for replication experiments. A Danish genome‐wide scan has prior reported evidence for candidate regions for asthma susceptibility genes on chromosomes 1p, 5q, 6p, 12q and Xp. Linkage to chromosome 12q was later confirmed in the same replication sample as used in the present study. The aim of the study was to replicate linkage to candidate regions for asthma in an independent Danish sample.Methods:  We performed a replication study investigating linkage to candidate regions for asthma on chromosomes 1p36.31‐p36.21, 5q15‐q23.2, 6p24.3‐p22.3, and Xp22.31‐p11.4 using additional markers in an independent set of 136 Danish asthmatic sib pair families.Results:  Nonparametric multipoint linkage analyses yielded suggestive evidence for linkage to asthma to chromosome Xp21.2 (MLS 2.92) but failed to replicate linkage to chromosomes 1p36.31‐p36.21, 5q15‐q23.2 and 6p24.3‐p22.3.Conclusions:  The replication results provide evidence for chromosome Xp21 to harbour a susceptibility gene for asthma in the Danish population. To our knowledge, the study is the first to replicate evidence for linkage to chromosome X. A susceptibility gene for asthma on chromosome X could potentially explain observed gender differences in asthma prevalence.
The effect of IVX‐0142, a heparin‐derived hypersulfated disaccharide, on the allergic airway responses in asthma
Authors: Duong M. , Cockcroft D. , Boulet L.‐P. , Ahmed T. , Iverson H. , Atkinson D. C. , Stahl E. G. , Watson R. , Davis B. , Milot J. , Gauvreau G. M. , O’Byrne P. M. 
Published: August 2008

Background: IVX‐0142 is a heparin‐derived hypersulfated disaccharide devoid of anticoagulant activity while possessing anti‐allergic and anti‐inflammatory activity in preclinical studies. In a proof‐of‐concept study, the allergen inhalation challenge model was used to investigate the effect of IVX‐0142 in mild atopic asthma.Methods: Nineteen subjects, not on controller medications, were randomized to an evaluator‐blind, placebo‐controlled, cross‐over study. The effect of a single nebulized dose of IVX‐0142 (80 mg) or placebo administered 30 min prior to allergen inhalation was evaluated on the allergic airway responses, airway responsiveness, and airway inflammation.Results: When compared with placebo, 14 and 13 subjects experienced a relatively smaller maximum fall in forced expiratory volume in 1 s (maxFEV1%) for the early airway response (EAR) and late airway response (LAR) with IVX‐0142, respectively (P < 0.01). The degree of attenuation in the EAR [maxFEV1% (mean ± SE) 26.5 ± 2.8%vsplacebo 31.0 ± 2.8%,P = 0.059] and LAR (15.6 ± 2.9%vsplacebo 19.0 ± 2.9%,P = 0.24) with IVX‐0142, however, was small and did not reach statistical significance compared with placebo. Similarly, a trend in the attenuation of allergen‐induced increase in the absolute sputum cell counts was also observed. No difference in the allergen‐induced increase in airway hyper‐responsiveness and exhaled nitric oxide was noticed.Conclusions: The majority of mild atopic asthmatics demonstrated a reduction in the EAR and LAR to IVX‐0142. However, the treatment effect observed with a single prechallenge dose of IVX‐0142 was small and heterogeneous. The potential anti‐allergic and anti‐inflammatory effects using multiple higher doses need to be evaluated.
Induced sputum and bronchial mucosal expression of interleukin‐13 is not increased in chronic obstructive pulmonary disease
Authors: Saha S. , Mistry V. , Siva R. , Parker D. , May R. , Bradding P. , Pavord I. D. , Brightling C. E. 
Published: August 2008

Background:  The Th2 cytokine interleukin‐13 (IL‐13) has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). We sought to examine IL‐13 expression in COPD subjects in induced sputum and bronchus specimens. We hypothesized that inflammatory cells expressing IL‐13 localize to the airway smooth muscle bundle and bronchial glands.Methods:  Interleukin‐13 was measured in sputum samples from subjects with COPD (n = 34) across a range of severity (Global initiative for chronic Obstructive Lung Disease 2–4) and controls (n = 14) using ELISA. IL‐13+ cells and inflammatory cells were enumerated within surgically resected proximal airway using immunohistochemical techniques from subjects with COPD (n = 10), smoking (n = 10) and nonsmoking controls (n = 8).Results:  Sputum IL‐13 was measurable in only 6/34 subjects with COPD and was not found in the smoking or nonsmoking control subjects. In subjects with COPD and controls there was a paucity of IL‐13+ cells. The distribution of inflammatory cells within different airway compartments was similar in COPD and controls except for an increase in CD3+ lymphocytes within bronchial glands in COPD (P = 0.04).Conclusions:  Our findings do not support a role for IL‐13 in COPD. However, the tissue localization of inflammatory cells to airway compartments, particularly the increase of T cells in glands in COPD may be important in disease.
A new method of concentrating hepatitis B virus (HBV) DNA and HBV surface antigen: an application of the method to the detection of occult HBV infection
Authors: Satoh K. , Iwata‐Takakura A. , Yoshikawa A. , Gotanda Y. , Tanaka T. , Yamaguchi T. , Mizoguchi H. 
Published: August 2008

Background  The risk of post‐transfusion hepatitis B virus (HBV) infection has been reduced after the implementation of HBV nucleic acid amplification technology (NAT). However, the problem of HBV DNA‐positive and HBV surface antigen (HBsAg)‐negative occult HBV infections remains to be solved. This is in part due to the HBV DNA load being too low to detect these occult HBV infections using mini‐pool NAT. In Japan, the assay for the antibody against the HBV core antigen (anti‐HBc) has not completely excluded occult HBV infection. To solve this problem, we have developed a new method of concentrating HBV DNA and HBsAg simultaneously to increase the sensitivity of detection tests.Methods  Virus concentration is achieved by the enhancement of the agglutination of viruses using poly‐L‐lysine in the presence of a bivalent metal. Poly‐L‐lysine‐coated magnetic beads are used to shorten the time of each step of the concentration procedure. Seventy‐seven anti‐HBc‐positive and HBsAg‐negative donations were examined. HBsAg and anti‐HBc were tested by enzyme immunoassay (EIA) (AxSYM; Abbott) and haemagglutination inhibition test (Japanese Red Cross), respectively.Results  HBV surface antigen and HBV DNA levels were concentrated up to four‐ to sevenfold. Using this method, 35 of the 77 anti‐HBc‐positive and HBsAg‐negative donors were HBV DNA‐positive by individual NAT and a further five donors became HBV DNA‐positive by HBV concentration. Twenty‐seven of 40 occult HBV infections became HBsAg‐positive by HBsAg concentration.Conclusion  Our new method of concentrating HBV and HBsAg increased the sensitivities of EIA and HBV NAT, and enabled us to detect 27 of 40 occult HBV infections by HBsAg EIA.
Reproductive Performance of Gilts with Similar Age but with Different Growth Rate at the Onset of Puberty Stimulation
Authors: Kummer R , Bernardi ML , Schenkel AC , Amaral Filha WS , Wentz I , Bortolozzo FP 
Published: August 2008

ContentsThe aim of this study was to evaluate the reproductive performance of gilts that had a similar age but different weights at the onset of puberty stimulation by boar exposure at 144 days. Gilts were divided into two groups according to their lifetime growth rate from birth to approximately 144 days of age. Mean growth rates at this moment were 577 and 724 g/day for group 1 (G1; n = 58) and group 2 (G2; n = 58), respectively. After selection, gilts were weighed at approximately 155, 165 and 175 days of age, on the insemination day and at slaughter. Gilts were inseminated, on average, at 193 days of age and were slaughtered 32 days after insemination, when the number of corpora lutea and embryos were recorded. Higher growth rate gilts (G2) reached puberty earlier (155.3 vs 164.1 days; p < 0.01). More gilts of G2 group attained puberty by 190 days of age (p = 0.004) than G1 gilts (95%; 55/58 vs 76%; 44/58). The anoestrous rate, until 60 days after the onset of boar exposure was higher (p < 0.01) in G1 (19.0%; 11/58) than in G2 (3.4%; 2/58) group. However, there were no differences in the pregnancy rate (90.7 vs 94.5), ovulation rate (15.9 vs 16.5), total embryos (12.9 vs 11.7), viable embryos (12.0 vs 11.1) and embryo survival (73.7% vs 68.5%), between G1 gilts and G2 gilts, respectively (p > 0.05). High growth rate gilts attain puberty earlier and have a lower anoestrous rate than low growth rate gilts.