bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human dendritic cells transfected with allergen‐DNA stimulate specific immunoglobulin G4 but not specific immunoglobulin E production of autologous B cells from atopic individuals in vitro
Authors: König Bettina , Petersen Arnd , Bellinghausen Iris , Böttcher Ingo , Becker Wolf‐Meinhard , Knop Jürgen , Saloga Joachim 
Published: May 2007

SummaryAtopic/allergic diseases are characterized by T helper 2 (Th2)‐dominated immune responses resulting in immunoglobulin E (IgE) production. DNA‐based immunotherapies have been shown to shift the immune response towards Th1 in animal models. In further studies we showed that human dendritic cells (DC) transfected with allergen‐DNA are able to stimulate autologous CD4+ T cells from atopic individuals to produce Th1 instead of Th2 cytokines and to activate interferon‐γ (IFN‐γ)‐producing CD8+ T cells. The aim of this study was to analyse whether DC transfected with allergen‐DNA are also able to influence immunoglobulin production of B cells from atopic donors. For this purpose, human monocyte‐derived DC from grass‐pollen allergic donors were transfected with an adenovirus encoding the allergen Phleum pratense 1 and cocultured with B cells, autologous CD4+ T cells, and CD40 ligand‐transfected L‐cells. B cells receiving help from CD4+ T cells stimulated with allergen‐transfected dendritic cells produced more allergen‐specific IgG4 compared to stimulation with allergen protein pulsed DC or medium, while total IgG4 production was not affected. In contrast, specific IgE production was not enhanced by stimulation with allergen‐DNA transfected DC compared to medium and inhibited compared to allergen protein‐pulsed DC with similar effects on total IgE production in vitro. Allergen‐DNA transfected dendritic cells are able to direct the human allergic immune response from Th2‐dominance towards Th1 and Tc1 also resulting in decreased IgE and increased IgG4 production.
In vitro microleakage of a fissure sealant polymerized by either a quartz tungsten halogen curing light or a plasma arc curing light
Authors: SHAH SARAH , ROEBUCK ELIZABETH M. , NUGENT ZOANN , DEERY CHRIS 
Published: May 2007

Background.  The benefits of using plasma arc curing lights with their shorter curing times in the management of children are potentially great, provided there are no adverse effects.Objective.  The aim of this study was to investigate whether the microleakage of a resin‐based sealant is influenced by polymerization with either a conventional quartz tungsten halogen or a plasma arc curing light.Design.  This study took the form of an in vitro randomized control trial. Seventy extracted human first and second permanent premolars and molars were randomly allocated into two groups. Their occlusal surfaces were sealed with a light‐cured fissure sealant using either a quartz tungsten halogen curing light or a plasma arc curing light. The teeth were then sectioned, resulting in four surfaces per tooth, which were examined for microleakage under × 15 magnification with a light microscope. The principal unit of analysis was the tooth (worst section score) and not the section microleakage score.Results.  No statistical significant difference in microleakage scoring between the two groups was demonstrated.Conclusion.  This study found no difference in the degree of microleakage of fissure sealants polymerized by either light source.
Dominant pathogenic species of mesophilic aeromonads isolated from diseased and healthy fish cultured in Poland
Authors: Kozińska A 
Published: May 2007

AbstractAeromonasisolates were collected from cultured fish, characterized phenotypically and identified to species using 16S rDNA. The pathogenicity of all isolates was assayed on the basis of haemolytic and proteolytic activity and challenge tests were performed for isolates from healthy fish. A total of 131Aeromonasisolates were obtained and identified as follows:A. hydrophila(13),A. bestiarum(23),A. salmonicida(motile biogroup) (19),A. caviae(2),A. sobria(18),A. veroniibt.sobria(42),A. jandaei(1),A. encheleia(11) andA. allosaccharophila(2). All isolates ofA. hydrophilaandA. bestiarumand most isolates ofA. salmonicidaandA. veroniiwere classified as pathogenic.Aeromonas hydrophilawas isolated only from diseased trout except for one isolate obtained from carp fry. The other potentially pathogenicAeromonasspecies were present in diseased as well as healthy fish. The pathogenicity of isolates from healthy fish was correlated with their enzymatic activity and was also tested by challenge experiments. The dominant pathogenic species wereA. veroniibt.sobria,A. bestiarumandA. salmonicidain common carp andA. hydrophilain rainbow trout.
Experimental infection of turbot, Psetta maxima (L.), with strains of viral haemorrhagic septicaemia virus isolated from wild and farmed marine fish
Authors: López‐Vázquez C , Dopazo C P , Barja J L , Bandín I 
Published: May 2007

AbstractThe susceptibility of turbot, Psetta maxima, to infection with two strains of viral haemorrhagic septicaemia virus (VHSV) obtained from wild Greenland halibut, Reinhardtius hippoglossoides, and from farmed turbot was examined. A marine VHSV strain known to be highly pathogenic for turbot was also utilized for comparative purposes. Fish were infected by intra‐peritoneal (i.p.), immersion or cohabitation, and maintained at two different temperatures (8 and 15 °C). Infection trials showed that the three VHSV isolates were pathogenic for turbot fingerlings by i.p. injection at both temperatures, with high levels of mortality. Virus was recovered from most pools of dead fish i.p. challenged, but not from surviving fish. Although clinical signs were not induced following waterborne exposure, viral growth was obtained from some pools of surviving fish challenged by immersion with strain GH40 from Greenland halibut, which indicates that the virus can survive in sea water and infect other fish via horizontal transmission. Furthermore, although low, the clinical signs and mortality observed in fish cohabitating with turbot challenged with strain GH40 confirms horizontal transmission and indicates that the passage through fish increases the virulence of this strain for turbot. These findings indicate that Greenland halibut, as other wild fish, may play an important role in the epizootiology of VHSV and suggest a potential risk for the turbot farming industry.
An individual with Gilles de la Tourette syndrome and Smith–Magenis microdeletion syndrome: is chromosome 17p11.2 a candidate region for Tourette syndrome putative susceptibility genes?
Authors: Shelley B. P. , Robertson M. M. , Turk J. 
Published: May 2007

AbstractThis is the first published case description in the current literature of the association of definite Gilles de la Tourette syndrome (GTS) and the Smith–Magenis syndrome (SMS), both confirmed by DSM‐IV‐TR criteria and molecular cytogenetic analysis, respectively. The co‐occurrence of GTS, SMS and their common behavioural/neuropsychiatric abnormalities should warrant further genetic investigation of chromosome 17p11.2 deletion site as it may be a promising region for containing a gene(s) of aetiological importance in the development of the GTS phenotype. Alternatively, the co‐occurrence may be due to the common endophenotypic mechanisms shared by these disorders, rather than being specific for GTS that could be explored using strategies of quantitative trait loci – endophenotype‐based approach. Research into this genomic region may also benefit psychiatric genetic research in enhancing understanding of the biological and molecular underpinnings of common behavioural problems that are seen in both GTS and SMS. This would lead to advancement in neurobehavioural/neuropsychiatric genetics which will help in further explaining the broader perspective of gene–brain–behaviour interrelationships.
Silenced grief: living with the death of a child with intellectual disabilities
Authors: Todd S. 
Published: May 2007

AbstractBackground  This paper examines the bereavement experiences of parents of people with intellectual disabilities (IDs). It is based upon an understanding that there exists little research‐based understanding of those experiences or of the support needs of parents after the death of their child.Methods  In‐depth interviews were held with 13 parents on the deaths of their children with IDs.Results  The data highlighted the deep sense of loss that these parents experience after the death of their child. The loss was intensely felt. They also show that their loss was a form of compounded loss. To begin with the scale and depth of loss is misrecognized. They also lose contact with a world that they had previously been heavily involved in. There was a sense that ID services and professionals withdrew from the family with too much haste. The data reveal that there exists no adequate supportive emotional community for these parents to express their grief.Conclusions  It is argued that the experiences of these parents have much in common with understandings of disenfranchised grief. The implications of these findings for research and practice are briefly discussed.
The quorum sensing regulator HapR downregulates the expression of the virulence gene transcription factor AphA in Vibrio cholerae by antagonizing Lrp‐ and VpsR‐mediated activation
Authors: Lin Wei , Kovacikova Gabriela , Skorupski Karen 
Published: May 2007

SummaryHapR is a quorum sensing‐regulated transcription factor that represses the virulence cascade in Vibrio cholerae by binding to a specific site centred at −71 in the aphA promoter, ultimately preventing activation of the tcpPH promoter on the Vibrio pathogenicity island. In an effort to elucidate the mechanism by which HapR represses aphA expression, we identified two transcriptional regulators, Lrp and VpsR, both of which activate the aphA promoter. Lrp, the leucine‐responsive regulatory protein, binds to a region between −136 and −123 in the promoter to initiate aphA expression. VpsR, the response regulator that controls biofilm formation, binds to a region between −123 and −73 to activate aphA expression. HapR represses aphA expression by antagonizing the functions of both of these activators. The HapR binding site at −71 lies downstream of the Lrp binding site and overlaps the VpsR binding site. HapR binding thus directly blocks access of VpsR to the promoter. A naturally occurring point mutation in the aphA promoter (G‐77T), which has previously been shown to prevent HapR binding, also prevents VpsR binding. In the absence of HapR, either Lrp or VpsR is capable of achieving nearly full expression of the aphA promoter, but when present together their effects are to some degree additive. The aphA promoter is also negatively autoregulated and an AphA binding site is centred at −20. The results here provide a model for the dual activation of the aphA promoter by Lrp and VpsR as well as its dual repression by HapR and AphA.
The novel ER membrane protein PRO41 is essential for sexual development in the filamentous fungus Sordaria macrospora
Authors: Nowrousian Minou , Frank Sandra , Koers Sandra , Strauch Peter , Weitner Thomas , Ringelberg Carol , Dunlap Jay C. , Loros Jennifer J. , Kück Ulrich 
Published: May 2007

SummaryThe filamentous fungus Sordaria macrospora develops complex fruiting bodies (perithecia) to propagate its sexual spores. Here, we present an analysis of the sterile mutant pro41 that is unable to produce mature fruiting bodies. The mutant carries a deletion of 4 kb and is complemented by the pro41 open reading frame that is contained within the region deleted in the mutant. In silico analyses predict PRO41 to be an endoplasmic reticulum (ER) membrane protein, and a PRO41–EGFP fusion protein colocalizes with ER‐targeted DsRED. Furthermore, Western blot analysis shows that the PRO41–EGFP fusion protein is present in the membrane fraction. A fusion of the predicted N‐terminal signal sequence of PRO41 with EGFP is secreted out of the cell, indicating that the signal sequence is functional. pro41 transcript levels are upregulated during sexual development. This increase in transcript levels was not observed in the sterile mutant pro1 that lacks a transcription factor gene. Moreover, microarray analysis of gene expression in the mutants pro1, pro41 and the pro1/41 double mutant showed that pro41 is partly epistatic to pro1. Taken together, these data show that PRO41 is a novel ER membrane protein essential for fruiting body formation in filamentous fungi.
Multiple mechanisms to ameliorate the fitness burden of mupirocin resistance in Salmonella typhimurium
Authors: Paulander Wilhelm , Maisnier‐Patin Sophie , Andersson Dan I. 
Published: May 2007

SummaryWe examined how the fitness costs of mupirocin resistance caused by mutations in the chromosomal isoleucyl–tRNA synthetase gene (ileS) can be ameliorated. Mupirocin‐resistant mutants were isolated and four different, resistance‐conferring point mutations in the chromosomal ileS gene were identified. Fifty independent lineages of the low‐fitness, resistant mutants were serially passaged to evolve compensated mutants with increased fitness. In 34/50 of the evolved lineages, the increase in fitness resulted from additional point mutations in isoleucine tRNA synthetase (IleRS). Measurements in vitro of the kinetics of aminoacylation of wild‐type and mutant enzymes showed that resistant IleRS had a reduced rate of aminoacylation due to altered interactions with both tRNAIle and ATP. The intragenic compensatory mutations improved IleRS kinetics towards the wild‐type enzyme, thereby restoring bacterial fitness. Seven of the 16 lineages that lacked second‐site compensatory mutations in ileS, showed an increase in ileS gene dosage, suggesting that an increased level of defective IleRS compensate for the decrease in aminoacylation activity. Our findings show that the fitness costs of ileS mutations conferring mupirocin resistance can be reduced by several types of mechanisms that may contribute to the stability of mupirocin resistance in clinical settings.
The tubulin homologue FtsZ contributes to cell elongation by guiding cell wall precursor synthesis in Caulobacter crescentus
Authors: Aaron Michelle , Charbon Godefroid , Lam Hubert , Schwarz Heinz , Vollmer Waldemar , Jacobs‐Wagner Christine 
Published: May 2007

SummaryThe tubulin homologue FtsZ is well known for its essential function in bacterial cell division. Here, we show that in Caulobacter crescentus, FtsZ also plays a major role in cell elongation by spatially regulating the location of MurG, which produces the essential lipid II peptidoglycan cell wall precursor. The early assembly of FtsZ into a highly mobile ring‐like structure during cell elongation is quickly followed by the recruitment of MurG and a major redirection of peptidoglycan precursor synthesis to the midcell region. These FtsZ‐dependent events occur well before cell constriction and contribute to cell elongation. In the absence of FtsZ, MurG fails to accumulate near midcell and cell elongation proceeds unperturbed in appearance by insertion of peptidoglycan material along the entire sidewalls. Evidence suggests that bacteria use both a FtsZ‐independent and a FtsZ‐dependent mode of peptidoglycan synthesis to elongate, the importance of each mode depending on the timing of FtsZ assembly during elongation.
Transcriptional and physiological adaptation to defective protein‐O‐mannosylation in Candida albicans
Authors: Cantero Pilar D. , Lengsfeld Christian , Prill Stephan K.‐H. , Subanović Marina , Román Elvira , Pla Jesús , Ernst Joachim F. 
Published: May 2007

SummaryFive Pmt isoforms O‐mannosylate secretory proteins in Candida albicans. Comparisons of genome‐wide transcript patterns of each pmt mutant revealed commonly downregulated genes involved in glycolysis and glycerol production. Increased phosphorylation of the Cek1p‐ but not the Mkc1p‐MAP kinase, as well as increased transcript levels for some stress‐related genes were detected in the pmt1 strain but not in the other pmt mutants. The transcriptomal pattern after short‐term inhibition of Pmt1p activity confirmed stress responses, but did not indicate an alteration of glycolytic flow. Short‐ but not long‐term adaptation to Pmt1p inhibition required signalling components Cek1p, Mkc1p, Efg1p and Tpk1p. Cna1p (calcineurin) but not its downstream effectors Crz1p and Crz2p was generally essential to allow growth during Pmt1p inhibition; accordingly, cyclosporin A strongly inhibited growth of the pmt1 mutant. The lack of Pmt isoforms influenced transcript levels for the remaining isoforms both positively and negatively, suggesting complex cross‐regulation among PMT genes. These results confirm individual functions of Pmt isoforms but suggest a common biphasic adaptation response to Pmt deficiency. While known signalling pathways modulate adaptation for a short‐term, long‐term adaptation requires calcineurin, adjustments of remaining Pmt activities and of glycolytic flow.
Cell wall growth during elongation and division: one ring to bind them?
Authors: Scheffers Dirk‐Jan 
Published: May 2007

SummaryThe role of the cell division protein FtsZ in bacterial cell wall (CW) synthesis is believed to be restricted to localizing proteins involved in the synthesis of the septal wall. In this issue of Molecular Microbiology, the groups of Christine Jacobs‐Wagner and Waldemar Vollmer provide compelling evidence that in Caulobacter crescentus, FtsZ plays an additional role in CW synthesis in non‐dividing cells. During elongation (cell growth) FtsZ is responsible for the incorporation of CW material in a zone at the midcell by recruiting MurG, a protein involved in peptidoglycan (PG) precursor synthesis. This resembles earlier findings of FtsZ mediated PG synthesis activity in Escherichia coli. A role of FtsZ in PG synthesis during elongation forces a rethink of the current model of CW synthesis in rod‐shaped bacteria.
Selection of ThAr lines for wavelength calibration of echelle spectra and implications for variations in the fine-structure constant
Authors: Murphy M. T. , Tzanavaris P. , Webb J. K. , Lovis C. 
Published: May 2007

Abstract
Echelle spectrographs currently provide some of the most precise and detailed spectra in astronomy, the interpretation of which sometimes depends on the wavelength calibration accuracy. In some applications, such as constraining cosmological variations in the fundamental constants from quasar absorption lines, the wavelength calibration is crucial. Here we detail an algorithm for selecting thorium–argon (ThAr) emission lines for wavelength calibration which incorporates the properties of both a new laboratory wavelength list and the spectrograph of interest. We apply the algorithm to the Very Large Telescope Ultraviolet and Visual Echelle Spectrograph (UVES) and demonstrate a factor of ≳3 improvement in the wavelength calibration residuals (i.e. random errors) alone. It is also found that UVES spectra calibrated using a previous, widely distributed line-list contain systematic ±30 –75 m s−1 distortions of the wavelength scale over both short and long wavelength ranges. These distortions have important implications for current UVES constraints on cosmological variations in the fine-structure constant. The induced systematic errors are most severe for Mg/Feii quasar absorbers in the redshift range 1.2 ≲zabs≲ 2.3, with individual absorbers studied by recent authors containing systematic errors up to four times larger than quoted statistical errors.
Does growth irradiance affect temperature dependence and thermal acclimation of leaf respiration? Insights from a Mediterranean tree with long‐lived leaves
Authors: ZARAGOZA‐CASTELLS JOANA , SÁNCHEZ‐GÓMEZ DAVID , VALLADARES FERNANDO , HURRY VAUGHAN , ATKIN OWEN K. 
Published: May 2007

ABSTRACTUnderstanding the response of leaf respiration (R) to changes in irradiance and temperature is a prerequisite for predicting the impacts of climate change on plant function and future atmospheric CO2concentrations. Little is known, however, about the interactive effects of irradiance and temperature on leafR. We investigated whether growth irradiance affects the temperature response of leafRin darkness (Rdark) and in light (Rlight) in seedlings of a broad‐leaved evergreen species,Quercus ilex. Two hypotheses concerningRdarkwere tested: (1) the Q10(i.e. the proportional increase inRper 10 °C rise in temperature) of leafRdarkis lower in shaded plants than in high‐light‐grown plants, and (2) shade‐grown plants exhibit a lower degree of thermal acclimation ofRdarkthan plants exposed to higher growth irradiance. We also assessed whether light inhibition ofRlightdiffers between leaves exposed to contrasting temperatures and growth irradiances, and whether the degree of thermal acclimation ofRlightis dependent on growth irradiance. We showed that while growth irradiance did impact on photosynthesis, it had no effect on the Q10of leafRdark. Growth irradiance had little impact on thermal acclimation when fully expanded, pre‐existing leaves were exposed to contrasting temperatures for several weeks. WhenRlightwas measured at a common irradiance,Rlight/Rdarkratios were higher in shaded plants due to homeostasis ofRlightbetween growth irradiance treatments and to the lowerRdarkin shaded leaves. We also showed thatRlightdoes not acclimate to the same degree asRdark, and thatRlight/Rdarkdecreases with increasing measuring and growth temperatures, irrespective of the growth irradiance. Collectively, we raised the possibility that predictive carbon cycle models can assume that growth irradiance and photosynthesis do not affect the temperature sensitivity of leafRdarkof long‐lived evergreen leaves, thus simplifying incorporation of leafRinto such models.
Chlororespiration and cyclic electron flow around PSI during photosynthesis and plant stress response
Authors: RUMEAU DOMINIQUE , PELTIER GILLES , COURNAC LAURENT 
Published: May 2007

ABSTRACTBesides major photosynthetic complexes of oxygenic photosynthesis, new electron carriers have been identified in thylakoid membranes of higher plant chloroplasts. These minor components, located in the stroma lamellae, include a plastidial NAD(P)H dehydrogenase (NDH) complex and a plastid terminal plastoquinone oxidase (PTOX). The NDH complex, by reducing plastoquinones (PQs), participates in one of the two electron transfer pathways operating around photosystem I (PSI), the other likely involving a still uncharacterized ferredoxin‐plastoquinone reductase (FQR) and the newly discovered PGR5. The existence of a complex network of mechanisms regulating expression and activity of the NDH complex, and the presence of higher amounts of NDH complex and PTOX in response to environmental stress conditions the phenotype of mutants, indicate that these components likely play a role in the acclimation of photosynthesis to changing environmental conditions. Based on recently published data, we propose that the NDH‐dependent cyclic pathway around PSI participates to the ATP supply in conditions of high ATP demand (such as high temperature or water limitation) and together with PTOX regulates cyclic electron transfer activity by tuning the redox state of intersystem electron carriers. In response to severe stress conditions, PTOX associated to the NDH and/or the PGR5 pathway may also limit electron pressure on PSI acceptor and prevent PSI photoinhibition.