bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystal structures of the effector‐binding domain of repressor Central glycolytic gene Regulator from Bacillus subtilis reveal ligand‐induced structural changes upon binding of several glycolytic intermediates
Authors: Řezáčová Pavlína , Kožíšek Milan , Moy Shiu F. , Sieglová Irena , Joachimiak Andrzej , Machius Mischa , Otwinowski Zbyszek 
Published: June 2008

SummaryExpression of genes in the gapA operon encoding five enzymes for triose phosphate interconversion in Bacillus subtilis is negatively regulated by the Central glycolytic genes Regulator (CggR). CggR belongs to the large SorC/DeoR family of prokaryotic transcriptional regulators, characterized by an N‐terminal DNA‐binding domain and a large C‐terminal effector‐binding domain. When no glucose is present in growth media, CggR binds to its target DNA sequence and blocks the transcription of genes in the gapA operon. In the presence of glucose, binding of the known effector molecule fructose‐1,6‐bisphosphate abolishes this interaction. We have identified dihydroxyacetone phosphate, glucose‐6‐phosphate and fructose‐6‐phosphate as additional CggR ligands that can bind to the effector‐binding site. Crystal structures of C‐CggR, the C‐terminal effector‐binding domain of CggR, both unliganded as well as in complex with the four ligands at resolutions between 1.65 and 1.80 Å reveal unique ligand‐specific structural changes in the binding site that affect the dimer interface. Binding affinities of these ligands were determined by isothermal titration calorimetry. Chemical cross‐linking shows that CggR oligomerization is mediated through its effector‐binding domain, and that binding of the different ligands differentially affects the distribution of oligomers. Electrophoretic mobility shift assays (EMSAs) confirmed a destabilizing effect of fructose‐1,6‐bisphosphate on the CggR/DNA complex, and also showed similar effects for dihydroxyacetone phosphate. Our results suggest that CggR stability and function may be modulated by various effectors in a complex fashion.
Knock‐down of the MEP pathway isogene 1‐deoxy‐d‐xylulose 5‐phosphate synthase 2 inhibits formation of arbuscular mycorrhiza‐induced apocarotenoids, and abolishes normal expression of mycorrhiza‐specific plant marker genes
Authors: Floß Daniela S. , Hause Bettina , Lange Peter R. , Küster Helge , Strack Dieter , Walter Michael H. 
Published: June 2008

SummaryThe first step of the plastidial methylerythritol phosphate (MEP) pathway is catalyzed by two isoforms of 1‐deoxy‐d‐xylulose 5‐phosphate synthase (DXS1 and DXS2). In Medicago truncatula, MtDXS1 and MtDXS2 genes exhibit completely different expression patterns. Most prominently, colonization by arbuscular mycorrhizal (AM) fungi induces the accumulation of certain apocarotenoids (cyclohexenone and mycorradicin derivatives) correlated with the expression of MtDXS2 but not of MtDXS1. To prove a distinct function of DXS2, a selective RNAi approach on MtDXS2 expression was performed in transgenic hairy roots of M. truncatula. Repression of MtDXS2 consistently led to reduced transcript levels in mycorrhizal roots, and to a concomitant reduction of AM‐induced apocarotenoid accumulation. The transcript levels of MtDXS1 remained unaltered in RNAi plants, and no phenotypical changes in non‐AM plants were observed. Late stages of the AM symbiosis were adversely affected, but only upon strong repression with residual MtDXS2‐1 transcript levels remaining below approximately 10%. This condition resulted in a strong decrease in the transcript levels of MtPT4, an AM‐specific plant phosphate transporter gene, and in a multitude of other AM‐induced plant marker genes, as shown by transcriptome analysis. This was accompanied by an increased proportion of degenerating and dead arbuscules at the expense of mature ones. The data reveal a requirement for DXS2‐dependent MEP pathway‐based isoprenoid products to sustain mycorrhizal functionality at later stages of the symbiosis. They further validate the concept of a distinct role for DXS2 in secondary metabolism, and offer a novel tool to selectively manipulate the levels of secondary isoprenoids by targeting their precursor supply.
Involvement of sphingosine kinase in plant cell signalling
Authors: Worrall Dawn , Liang Yun‐Kuan , Alvarez Sergio , Holroyd Geoff H. , Spiegel Sarah , Panagopulos Michael , Gray Julie E. , Hetherington Alistair M. 
Published: June 2008

SummaryIn mammalian cells sphingosine‐1‐phosphate (S1P) is a well‐established messenger molecule that participates in a wide range of signalling pathways. The objective of the work reported here was to investigate the extent to which phosphorylated long‐chain sphingoid bases, such as sphingosine‐1‐phosphate and phytosphingosine‐1‐phosphate (phytoS1P) are used in plant cell signalling. To do this, we manipulated Arabidopsis genes capable of metabolizing these messenger molecules. We show that Sphingosine kinase1 (SPHK1) encodes an enzyme that phosphorylates sphingosine, phytosphingosine and other sphingoid long‐chain bases. The stomata of SPHK1‐KD Arabidopsis plants were less sensitive, whereas the stomata of SPHK1‐OE plants were more sensitive, than wild type to ABA. The rate of germination of SPHK1‐KD was enhanced, whereas the converse was true for SPHK1‐OE seed. Reducing expression of either the putative Arabidopsis S1P phosphatase (SPPASE) or the DPL1 gene, which encodes an enzyme with S1P lyase activity, individually, had no effect on guard‐cell ABA signalling; however, stomatal responses to ABA in SPPASEDPL1 RNAi plants were compromised. Reducing the expression of DPL1 had no effect on germination; however, germination of SPPASE RNAi seeds was more sensitive to applied ABA. We also found evidence that expression of SPHK1 and SPPASE were coordinately regulated, and discuss how this might contribute to robustness in guard‐cell signalling. In summary, our data establish SPHK1 as a component in two separate plant signalling systems, opening the possibility that phosphorylated long‐chain sphingoid bases such as S1P and phytoS1P are ubiquitous messengers in plants.
Arabidopsis XXT5 gene encodes a putative α‐1,6‐xylosyltransferase that is involved in xyloglucan biosynthesis
Authors: Zabotina Olga A. , Van De Ven Wilhelmina T.G. , Freshour Glenn , Drakakaki Georgia , Cavalier David , Mouille Gregory , Hahn Michael G. , Keegstra Kenneth , Raikhel Natasha V. 
Published: June 2008

SummaryThe function of a putative xyloglucan xylosyltransferase from Arabidopsis thaliana (At1g74380; XXT5) was studied. The XXT5 gene is expressed in all plant tissues, with higher levels of expression in roots, stems and cauline leaves. A T‐DNA insertion in the XXT5 gene generates a readily visible root hair phenotype (root hairs are shorter and form bubble‐like extrusions at the tip), and also causes the alteration of the main root cellular morphology. Biochemical characterization of cell wall polysaccharides isolated from xxt5 mutant seedlings demonstrated decreased xyloglucan quantity and reduced glucan backbone substitution with xylosyl residues. Immunohistochemical analyses of xxt5 plants revealed a selective decrease in some xyloglucan epitopes, whereas the distribution patterns of epitopes characteristic for other cell wall polysaccharides remained undisturbed. Transformation of xxt5 plants with a 35S::HA‐XXT5 construct resulted in complementation of the morphological, biochemical and immunological phenotypes, restoring xyloglucan content and composition to wild‐type levels. These data provide evidence that XXT5 is a xyloglucan α‐1,6‐xylosyltransferase, and functions in the biosynthesis of xyloglucan.
The pentatricopeptide repeat gene OTP51 with two LAGLIDADG motifs is required for the cis‐splicing of plastid ycf3 intron 2 in Arabidopsis thaliana
Authors: De Longevialle Andéol Falcon , Hendrickson Luke , Taylor Nicolas L. , Delannoy Etienne , Lurin Claire , Badger Murray , Millar A. Harvey , Small Ian 
Published: June 2008

SummaryThe Arabidopsis thaliana chloroplast contains 20 group‐II introns in its genome, and seven known splicing factors are required for the splicing of overlapping subsets of 19 of them. We describe an additional protein (OTP51) that specifically promotes the splicing of the only group‐II intron for which no splicing factor has been described previously. This protein is a pentatricopeptide repeat (PPR) protein containing two LAGLIDADG motifs found in group‐I intron maturases in other organisms. Amino acids thought to be important for the homing endonuclease activity of other LAGLIDADG proteins are missing in this protein, but the amino acids described to be important for maturase activity are conserved. OTP51 is absolutely required for the splicing of ycf3 intron 2, and also influences the splicing of several other group‐IIa introns. Loss of OTP51 has far‐reaching consequences for photosystem‐I and photosystem‐II assembly, and for the photosynthetic fluorescence characteristics of mutant plants.
Ready‐to‐use introduction schedules for first exposure to allergenic foods in children at home
Authors: Vlieg‐Boerstra B. J. , Dubois A. E. J. , Van Der Heide S. , Bijleveld C. M. A. , Wolt‐Plompen S. A. A. , Oude Elberink J. N. G. , Kukler J. , Jansen D. F. , Venter C. , Duiverman E. J. 
Published: June 2008

Background:  The vast majority of children will undergo their first exposure to common allergenic foods at home. However, the first exposure may lead to clinical reactions. It has been proposed to introduce allergenic foods gradually into the diets of children at risk for food allergy, but no practical dietary advice has been devised.Objective:  The aim of this study was to devise safe introduction schedules for common allergenic foods for use at home, based on the challenge doses as administered in double‐blind, placebo‐controlled food challenge (DBPCFCs) in children who were never exposed previously to these foods.Methods:  Seventy‐two DBPCFCs were performed in 63 children as a first known exposure. The incrementing challenge doses were converted into equivalent portions of these foods in their usual household form and incorporated in introduction schedules. The feasibility of the introduction scales was tested in parents of the children attending our clinic.Results:  Based on the results of the positive challenges (37) in which severe reactions did not occur, detailed introduction schedules and a reference photograph of the required increasing amounts of food were devised for use at home. Feasibility testing showed that, when using these introduction schedules, parents portioned the initial doses significantly lower than without detailed instructions.Conclusions:  The introduction schedules and reference photograph provide information for parents to introduce the required amounts of allergenic foods in initial low doses at home. This is expected to improve the safety of this procedure.
Adherence to the Mediterranean diet and fresh fruit intake are associated with improved asthma control
Authors: Barros R. , Moreira A. , Fonseca J. , Ferraz de Oliveira J. , Delgado L. , Castel‐Branco M. G. , Haahtela T. , Lopes C. , Moreira P. 
Published: June 2008

Background:  The traditional Mediterranean diet is claimed to possess antioxidant and immune‐regulatory properties in several chronic diseases. Typical Mediterranean foods have recently been associated with improvement of symptoms of asthma and rhinitis in children. However the effect of adherence to Mediterranean diet on adult asthma outcomes is unknown. We aimed to investigate the association between adherence to Mediterranean diet and asthma control.Methods:  Cross sectional study of 174 asthmatics, mean (SD) age of 40 (15) years. The patients were defined as controlled, in contrast to noncontrolled, if they showed FEV1 ≥ 80% of predicted, exhaled nitric oxide (NO) ≤35 ppb, and Asthma Control Questionnaire score <1. Dietary intake was obtained by a food frequency questionnaire, and Mediterranean diet was assessed by alternate Mediterranean Diet (aMED) Score. Logistic regression models adjusting for confounders were performed to estimate the association between Mediterranean diet and asthma control.Results:  Controlled asthmatics (23%) had significantly higher aMED Score, intake of fresh fruit, and lower intake of ethanol compared to noncontrolled (77%). High adherence to Mediterranean diet reduced 78% the risk of noncontrolled asthma after adjusting for gender, age, education, inhaled corticosteroids and energy intake (OR = 0.22; 95% CI = 0.05–0.85; P‐trend = 0.028). The higher intake of fresh fruit decreased the probability of having noncontrolled asthma (OR = 0.29; 95% CI = 0.10–0.83; P‐trend = 0.015), while the higher intake of ethanol had the opposite effect (OR = 3.16; 95% CI = 1.10–9.11; P‐trend = 0.035).Conclusion:  High adherence to traditional Mediterranean diet increased the likelihood of asthma to be under control in adults. The study introduces a novel link between diet and asthma control, as measured by symptoms, lung function and exhaled NO.
A 12‐week placebo‐controlled study of rupatadine 10 mg once daily compared with cetirizine 10 mg once daily, in the treatment of persistent allergic rhinitis
Authors: Fantin S. , Maspero J. , Bisbal C. , Agache I. , Donado E. , Borja J. , Mola O. , Izquierdo I. ,   on behalf of international Rupatadine study group
Published: June 2008

Background: With the current increasing incidence of allergies worldwide, new treatments showing efficacy and long term safety are needed for chronic conditions such as persistent allergic rhinitis (PER). New generation H1‐antihistamines have demonstrated anti‐allergic properties, which could possibly enhance their effectiveness in long‐term periods of treatment.Objective: To investigate the efficacy of rupatadine, in controlling symptoms of PER over a 12‐week period.Methods: A randomized, double blind, parallel‐group, placebo‐controlled study was carried out in patients aged older than 12 years with PER. Main inclusion criteria were: instantaneous total symptom score (i6TSS) ≥45, nasal obstruction score ≤12, and overall assessment of PER ≥2 as moderate during the first visit. The primary efficacy endpoint was the 12‐week average change from baseline of the patients’ i6TSS.Results: In all, 736 patients were selected. Of them, 543 (73.8%) were randomized in three different groups: placebo (n = 185), cetirizine (n = 175) and rupatadine (n = 183). Rupatadine (P = 0.008) but not cetirizine (P = 0.07) statistically reduced the baseline i6TSSvsplacebo (47.8%, 44.7% and 38.8%, respectively), after 12 weeks. Onset of action was observed at the first 24 h for both treatments (rupatadinevsplacebo,P = 0.013; cetirizinevsplacebo,P = 0.015). Furthermore, instantaneous total nasal symptoms score (iTNSS) (including nasal blockage) mean change from baseline showed a significant reduction with rupatadine 10 mg in comparison with placebo, along all treatment duration of 12 weeks. Study treatments were well tolerated.Conclusion: Rupatadine significantly relieves symptoms of PER, providing a rapid onset of action and maintains its effects over a long period of 12‐weeks.
Reported food allergy to peanut, tree nuts and fruit: comparison of clinical manifestations, prescription of medication and impact on daily life
Authors: Le T. M. , Lindner T. M. , Pasmans S. G. , Guikers C. L. H. , Van Hoffen E. , Bruijnzeel‐Koomen C. A. F. M. , Knulst A. C. 
Published: June 2008

Background: Peanut (PN), tree nuts (TN) and fruits are frequent causes of food allergy (FA). Peanut and TN are believed to cause more severe reactions than fruits. However, there are no studies comparing the severity of PN, TN and fruit allergy within one patient group.Methods: Four‐hundred and eleven adult patients referred to our tertiary allergy center with suspicion of FA completed a standardized questionnaire. Patients with a typical history of immunoglubulin E (IgE)‐mediated allergy, e.g. oropharyngeal symptoms to PN, TN (hazelnut, walnut, cashew nut) or fruit (apple, kiwi, peach, pear and cherry) were recruited (218/411). The objective was to evaluate differences in clinical severity between PN, TN and fruit allergy and how this was reflected by prescription of emergency medication and impact on daily life.Results: Eighty‐two percent of the included 218 patients were sensitized to the respective foods. The percentages of severe symptoms (i.e. respiratory or cardiovascular symptoms) in PN, TN and fruit allergic patients were respectively 47%, 39% and 31% (respiratory) and 11%, 5.0% and 3.4% (cardiovascular). Prescription and use of emergency medication (epinephrine, antihistamines and steroids) did not differ among the three groups. The majority of patients with a PN or TN allergy (72%) and fruit allergy (62%) reported that FA influences their daily life considerably.Conclusions: Fruit allergy causes less severe symptoms than TN and especially PN allergy. However, this is not reflected in the prescription or use of emergency medication. This may indicate that physicians are not fully acquainted with the guidelines for prescription of emergency medication. A high impact on daily life was found both in PN, TN and in fruit allergy.
Evaluation by double‐blind placebo‐controlled oral challenge of the clinical relevance of IgE antibodies against plant glycans
Authors: Mari A. , Ooievaar‐de Heer P. , Scala E. , Giani M. , Pirrotta L. , Zuidmeer L. , Bethell D. , Van Ree R. 
Published: June 2008

Background:  The clinical relevance of immunoglobulin E (IgE) to plant glycans is a longstanding debate. We sought to evaluate their clinical reactivity using the human glycoprotein lactoferrin expressed in rice.Methods:  Allergic patients with IgE antibodies against plant glycans were analyzed for the presence of IgE against rice‐produced lactoferrin. The potency of IgE to induce mediator release was assessed by basophil histamine release and skin prick tests (SPTs). Clinical relevance was evaluated by double‐blind placebo‐controlled oral challenge (DBPCOC).Results:  Twenty‐four of 29 sera (82.7%) with IgE antibodies against plant glycans demonstrated IgE binding to transgenic lactoferrin. In three of five cases transgenic lactoferrin induced histamine release. Compared to a control major grass pollen allergen lactoferrin concentrations needed for biological activity of IgE were 5–6 orders of magnitude higher. Skin prick test and DBPCOC were negative in five patients with potential clinical reactivity that volunteered to undergo these in vivo challenges.Conclusions:  Poor or no biological activity and lack of clinical relevance of IgE‐binding plant glycans (five out of five) was demonstrated using human lactoferrin expressed in rice as a model.
A case‐control study of the relation between plasma selenium and asthma in European populations: a GA2LEN project*
Authors: Burney P. , Potts J. , Makowska J. , Kowalski M. , Phillips J. , Gnatiuc L. , Shaheen S. , Joos G. , Van Cauwenberge P. , Van Zele T. , Verbruggen K. , Van Durme Y. , Derudder I. , Wohrl S. , Godnic‐Cvar J. , Salameh B. , Skadhauge L. , Thomsen G. , Zuberbier T. , Bergmann K. C. , Heinzerling L. , Renz H. , Al‐Fakhri N. , Kosche B. , Hildenberg A. , Papadopoulos N. G. , Xepapadaki P. , Zannikos K. , Gjomarkaj M. , Bruno A. , Pace E. , Bonini S. , Bresciani M. , Gramiccioni C. , Fokkens W. , Weersink E. J. M. , Carlsen K.‐H. , Bakkeheim E. , Loureiro C. , Villanueva C. M. , Sanjuas C. , Zock J.‐P. , Lundback B. , Janson C. 
Published: June 2008

Background:  There is evidence that selenium levels are relatively low in Europe and may be falling. Low levels of selenium or low activity of some of the enzymes dependent on selenium have been associated with asthma.Methods:  The GA2LEN network has organized a multicentre case–control study in Europe to assess the relation of plasma selenium to asthma. The network compared 569 cases in 14 European centres with a diagnosis of asthma and reporting asthma symptoms in the last 12 months with 576 controls from the same centres with no diagnosis of asthma and no asthmatic symptoms in the last 12 months.Results:  All cases and controls were selected from the same population defined by age and place of residence. Mean plasma selenium concentrations among the controls ranged from 116.3 μg/l in Palermo to 67.7 μg/l in Vienna and 56.1 μg/l among the children in Oslo. Random effects meta‐analysis of the results from the centres showed no overall association between asthma and plasma selenium [odds ratio (OR)/10 μg/l increase in plasma selenium: 1.04; 95% confidence interval (CI): 0.89–1.21] though there was a significantly protective effect in Lodz (OR: 0.48; 95% CI: 0.29–0.78) and a marginally significant adverse effect in Amsterdam (OR: 1.68; 95% CI: 0.98–2.90) and Ghent (OR: 1.35; 95% CI: 1.03–1.77).Conclusion:  This study does not support a role for selenium in protection against asthma, but effect modification and confounding cannot be ruled out.
Stability of asthma control with regular treatment: an analysis of the Gaining Optimal Asthma controL (GOAL) study
Authors: Bateman E. D. , Bousquet J. , Busse W. W. , Clark T. J. H. , Gul N. , Gibbs M. , Pedersen S. ,   on behalf of the GOAL Steering Committee and Investigators
Published: June 2008

Background:  Uncontrolled asthma is characterized by variability. Current asthma guidelines recommend focussing on the achievement and maintenance of control but few studies have examined in detail, using composite measures of control, the stability and potential duration of control once achieved. In this post‐hoc analysis of the results of the Gaining Optimal Asthma controL (GOAL) study, we examine the association between the level of asthma control achieved during the step‐up phase of the study and the stability of control experienced during the maintenance phase.Methods:  GOAL was a 1‐year, randomized, stratified, double‐blind study of 3421 patients with uncontrolled asthma, which compared salmeterol/fluticasone propionate combination with fluticasone propionate in achieving two composite, guideline‐based measures of control: totally controlled and well‐controlled asthma. We analysed the proportion and duration of time spent in control, the effect of treatment on asthma stability, and the impact of asthma control stability on unscheduled use of healthcare resources.Results:  In patients achieving well‐controlled or totally controlled asthma, at least well‐controlled asthma was maintained for a median of almost 3 and 6 months, and for more than 85% and 95% of weeks of follow‐up, respectively. A high level of stability was confirmed in a Markov analysis investigating transitional probability of change in control status. Variability in control was associated with increased probability of an unscheduled healthcare resource use (odds ratio: 1.06, P < 0.001).Conclusions:  Most patients achieving guideline‐defined control can maintain at least a similar level of control with regular, stable dosing, with little likelihood of losing control.