bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterologous microarray experiments used to identify the early gene response to heat stress in a coral reef fish
Authors: KASSAHN KARIN S. , CALEY M. JULIAN , WARD ALISTER C. , CONNOLLY ASHLEY R. , STONE GLENN , CROZIER ROSS H. 
Published: March 2007

AbstractCoral reef fishes are expected to experience rising sea surface temperatures due to climate change. How well tropical reef fishes will respond to these increased temperatures and which genes are important in the response to elevated temperatures is not known. Microarray technology provides a powerful tool for gene discovery studies, but the development of microarrays for individual species can be expensive and time‐consuming. In this study, we tested the suitability of a Danio rerio oligonucleotide microarray for application in a species with few genomic resources, the coral reef fish Pomacentrus moluccensis. Results from a comparative genomic hybridization experiment and direct sequence comparisons indicate that for most genes there is considerable sequence similarity between the two species, suggesting that the D. rerio array is useful for genomic studies of P. moluccensis. We employed this heterologous microarray approach to characterize the early transcriptional response to heat stress in P. moluccensis. A total of 111 gene loci, many of which are involved in protein processing, transcription, and cell growth, showed significant changes in transcript abundance following exposure to elevated temperatures. Changes in transcript abundance were validated for a selection of candidate genes using quantitative real‐time polymerase chain reaction. This study demonstrates that heterologous microarrays can be successfully employed to study species for which specific microarrays have not yet been developed, and so have the potential to greatly enhance the utility of microarray technology to the field of environmental and functional genomics.
The strength of reproductive isolation in two hybridizing food‐deceptive orchid species
Authors: MOCCIA MARIA DOMENICA , WIDMER ALEX , COZZOLINO SALVATORE 
Published: March 2007

AbstractReproductive isolation is of fundamental importance for maintaining species boundaries in sympatry. In orchids, the wide variety of pollination systems and highly diverse floral traits have traditionally suggested a prominent role for pollinator isolation, and thus for prezygotic isolation, as an effective barrier to gene flow among species. Here, we examined the nature of reproductive isolation betweenAnacamptis morioandAnacamptis papilionacea, two sister species of Mediterranean food‐deceptive orchids, in two natural hybrid zones. Comparative analyses of the two hybrid zones that are located on soils with volcanic origin and have different and well‐dated ages consistently revealed that all hybrid individuals were morphologically and genetically intermediate between the parental species, but had strongly reduced fitness. Molecular analyses based on nuclear ITS1 and (amplified fragment length polymorphism) AFLP markers clearly showed that all examined hybrids were F1hybrids, and that no introgression occurred between parental species. The maternally inherited plastid DNA markers indicated that hybridization betweenA. morioandA. papilionaceawas bidirectional, as confirmed by the molecular analysis of seed families. The genetic architecture of the two hybrid zones suggests that the two parental species easily and frequently hybridize in sympatry as a consequence of partial pollinator overlap but that strong postzygotic barriers reduce hybrid fitness and prevent gene introgression. These results corroborate that chromosomal divergence is instrumental for reproductive isolation between these food‐deceptive orchids and suggest that hybridization is of limited importance for their diversification.
Host‐specificity and coevolution among pollinating and nonpollinating New World fig wasps
Authors: MARUSSICH WENDY A. , MACHADO CARLOS A. 
Published: March 2007

AbstractFigs (Ficus spp., Moraceae) and their pollinating wasps (Hymenoptera, Agaonidae, Chalcidoidea) constitute a classic example of an obligate plant‐pollinator mutualism, and have become an ideal system for addressing questions on coevolution, speciation, and the maintenance of mutualisms. In addition to pollinating wasps, figs host several types of nonpollinating, parasitic wasps from a diverse array of Chalcid subfamilies with varied natural histories and ecological strategies (e.g. competitors, gallers, and parasitoids). Although a few recent studies have addressed the question of codivergence between specific genera of pollinating and nonpollinating fig wasps, no study has addressed the history of divergence of a fig wasp community comprised of multiple genera of wasps associated with a large number of sympatric fig hosts. Here, we conduct phylogenetic analyses of mitochondrial DNA sequences (COI) using 411 individuals from 69 pollinating and nonpollinating fig wasp species to assess relationships within and between five genera of fig wasps (Pegoscapus, Idarnes, Heterandrium, Aepocerus, Physothorax) associated with 17 species of New World Urostigma figs from section Americana. We show that host‐switching and multiple wasp species per host are ubiquitous across Neotropical nonpollinating wasp genera. In spite of these findings, cophylogenetic analyses (treemap 1.0, treemap 2.02β, and parafit) reveal evidence of codivergence among fig wasps from different ecological guilds. Our findings further challenge the classical notion of strict‐sense coevolution between figs and their associated wasps, and mirror conclusions from detailed molecular studies of other mutualisms that have revealed common patterns of diffuse coevolution and asymmetric specialization among the participants.
The bidirectional polar and unidirectional lateral flagellar motors of Vibrio alginolyticus are controlled by a single CheY species
Authors: Kojima Masaru , Kubo Rumi , Yakushi Toshiharu , Homma Michio , Kawagishi Ikuro 
Published: March 2007

SummaryThe bacterial flagellar motor is an elaborate molecular machine that converts ion‐motive force into mechanical force (rotation). One of its remarkable features is its swift switching of the rotational direction or speed upon binding of the response regulator phospho‐CheY, which causes the changes in swimming that achieve chemotaxis. Vibrio alginolyticus has dual flagellar systems: the Na+‐driven polar flagellum (Pof) and the H+‐driven lateral flagella (Laf), which are used for swimming in liquid and swarming over surfaces respectively. Here we show that both swimming and surface‐swarming of V. alginolyticus involve chemotaxis and are regulated by a single CheY species. Some of the substitutions of CheY residues conserved in various bacteria have different effects on the Pof and Laf motors, implying that CheY interacts with the two motors differently. Furthermore, analyses of tethered cells revealed that their switching modes are different: the Laf motor rotates exclusively counterclockwise and is slowed down by CheY, whereas the Pof motor turns both counterclockwise and clockwise, and CheY controls its rotational direction.
Cryo‐electron microscopy of cell division in Staphylococcus aureus reveals a mid‐zone between nascent cross walls
Authors: Matias Valério R. F. , Beveridge Terry J. 
Published: March 2007

SummaryCryo‐electron microscopy of frozen‐hydrated thin sections permits the observation of the real distribution of mass in biological specimens allowing the native structure of bacteria to be seen, including the natural orientation of their surface layers. Here, we use this approach to study the fine ultrastructure of the division site, or septum, of Staphylococcus aureus D2C. Frozen‐hydrated sections revealed a differentiated cell wall at the septum, showing two high‐density regions sandwiched between three low‐density zones. The two zones adjacent to the membrane appeared as an extension of the periplasmic space seen in this organism's cell envelope and showed no distinguishing structures within them. Immediately next to these were higher‐density zones that corresponded to nascent cross walls of the septum. Unexpectedly, a rather broad low‐density zone was seen separating cross walls in the septum. This mid‐zone of low density appeared inflated and without visible structures in isolated cell walls, which showed only the high‐density zones of the septum. Here, we suggest that frozen‐hydrated thin sections have captured a highly fragile septal region, the mid‐zone, which results from the dynamic action of autolysis and actively separates daughter cells during division. The two zones next to the membranes are periplasmic spaces. Immediately next to these are the growing cross walls composed of peptidoglycan, teichoic acid and protein.
Regulation and role of a STE12‐like transcription factor from the plant pathogen Colletotrichum lindemuthianum
Authors: Hoi Joanne Wong Sak , Herbert Corentin , Bacha Nafees , O'Connell Richard , Lafitte Claude , Borderies Gisèle , Rossignol Michel , Rougé Pierre , Dumas Bernard 
Published: March 2007

SummaryIn phytopathogenic fungi, STE12‐like genes encode transcription factors essential for appressorium‐mediated host penetration. However, their regulation and downstream targets are still unknown. In the present study, a STE12‐like gene (CLSTE12) from Colletotrichum lindemuthianum was isolated. We identified a spliced variant whose expression was negatively regulated during early stages of pathogenesis, whereas the correctly spliced mRNA remained expressed up to the penetration step, suggesting distinct roles for these two transcripts. Indeed, the full‐length sequence was able to complement a yeast STE12 mutant, whereas overexpression of the transcript variant had a dominant‐negative effect on yeast invasive growth and C. lindemuthianum pathogenicity. To further investigate the downstream genes that could be regulated by CLSTE12, disruption mutants were generated. Phenotypic analyses of the mutants revealed reduced pectinase activity and conidial adhesion to polystyrene. Analysis of cell surface proteins allowed the identification of a major protein, Clsp1p, which was absent from the mutants. Clsp1p belongs to a new family of wall‐associated proteins only found in euascomycetous fungi. Overall, these results suggest that the activity of CLSTE12 can be modulated by a regulated alternative splicing mechanism and that this factor is involved in the production of cell surface proteins and host cell wall degrading enzymes.
The two faces of Janus: virulence gene regulation by CovR/S in group A streptococci
Authors: Churchward Gordon 
Published: March 2007

SummaryThe group A streptococcus (GAS) causes a variety of human diseases, including toxic shock syndrome and necrotizing fasciitis, which are both associated with significant mortality. Even the superficial self‐limiting diseases caused by GAS, such as pharyngitis, impose a significant economic burden on society. GAS can cause a wide spectrum of diseases because it elaborates virulence factors that enable it to spread and survive in different environmental niches within the human host. The production of many of these virulence factors is directly controlled by the activity of the CovR/S two‐component regulatory system. CovS acts in one direction as a kinase primarily to activate the response regulator CovR and repress the expression of major virulence factors and in the other direction as a phosphatase to permit gene expression in response to environmental changes that mimic conditions found during human infection. This Janus‐like behaviour of the CovR/S system is recapitulated in the binding of CovR to the promoters that it directly regulates. Interactions between different faces of the CovR DNA binding domain appear to depend upon DNA sequence, leading to the potential for differential regulation of virulence gene expression.
Middle promoters constitute the most abundant and diverse class of promoters in bacteriophage T4
Authors: Stoškiene Giedre , Truncaite Lidija , Zajančkauskaite Aurelija , Nivinskas Rimas 
Published: March 2007

SummaryThe temporally regulated transcription program of bacteriophage T4 relies upon the sequential utilization of three classes of promoters: early, middle and late. Here we show that middle promoters constitute perhaps the largest and the most diverse class of T4 promoters. In addition to 45 T4 middle promoters known to date, we mapped 13 new promoters, 10 of which deviate from the consensus MotA box, with some of them having no obvious match to it. So, 30 promoters of 58 identified now deviate from the consensus sequence deduced previously. In spite of the differences in their sequences, the in vivo activities of these T4 middle promoters were demonstrated to be dependent on both activators, MotA and AsiA. Traditionally, the MotA box was restricted to a 9 bp sequence with the highly conserved motif TGCTT. New logo based on the sequences of currently known middle promoters supports the conclusion that the consensus MotA box is comprised of 10 bp with the highly conserved central motif GCT. However, some apparently good matches to the consensus of middle promoters do not produce transcripts either in vivo or in vitro, indicating that the consensus sequence alone does not fully define a middle promoter.
Comparative functional analysis of the lac operons in Streptococcus pyogenes
Authors: Loughman Jennifer A. , Caparon Michael G. 
Published: March 2007

SummaryHaving no known environmental reservoir, Streptococcus pyogenes, a bacterium responsible for a wider variety of human diseases than any other bacterial species, must rely on its host for metabolic substrates. Although a streptococcal aldolase, LacD.1, has been adapted to virulence gene regulation, both LacD.1 and a paralogous protein, LacD.2, are predicted to function in the tagatose 6‐phosphate pathway for lactose and galactose utilization. In order to gain insight into the mechanism of the LacD.1 regulatory pathway and the role of genome context in the emergence of LacD.1's novel regulatory functions, we compared the function and regulation of the Lac.1 and Lac.2 loci. The Lac.1 operon is not inducible, and regulation by LacD.1 is independent of a functional tagatose 6‐phosphate pathway and enhanced by the conserved truncation of upstream Lac.1 genes. In contrast, Lac.2 expression is sensitive to environmental carbohydrates, and LacD.2, not LacD.1, contributes to growth on galactose. Thus, we conclude that the Lac.1 locus has been specialized to participate in regulation, leaving efficient utilization of carbohydrate sources to the Lac.2 locus. The adaptation of LacD for transcription regulation may be an underappreciated strategy among prokaryotes, as homologues of this multifaceted enzyme are present in a broad range of species.
Epstein–Barr virus‐associated lymphoproliferative disease in oral cavity in a renal transplant recipient: A case report
Authors: Johnson J. , Kerecuk L. , Harrison M. , Taylor J. O. , Odell E. 
Published: March 2007

Abstract: A 10‐yr‐old child on long‐term cyclosporin immunosuppression for a renal transplant presented with gingival swelling enlargement, in a background of gingival hyperplasia. It is tempting to assume that it is a drug‐related lesion; perhaps, an area of plaque‐related inflammation. An incisional biopsy revealed a monomorphic B‐cell post‐transplant lymphoproliferative disease (PTLD). At this stage, high Epstein–Barrr virus (EBV) titres supported a diagnosis of EBV‐driven PTLD. Despite discontinuation of cyclosporin and reduction of EBV viral load to undetectable levels, there was considerable enlargement of the tumour. The patient underwent six courses of cyclophosphamide, vincristine and prednisolone chemotherapy. This resulted in a dramatic reduction in the size of the right mandibular mass with complete mucosal healing intra‐orally. Her renal transplant still has good function and there is no evidence of PTLD recurrence 23 months after initial diagnosis.This case illustrates that PTLD can manifest in unusual sites and in transplant recipients on cyclosporin immunosuppression it is easy to assume that any gingival hyperplasia is drug induced; however, the differential diagnosis of gingival hyperplasia should include PTLD.
The COUPLES‐project: a pooled analysis of patient and partner treatment satisfaction scale (TSS) outcomes following vardenafil treatment
Authors: Rosen Raymond C. , Fisher William A. , Beneke Manfred , Homering Martin , Evers Thomas 
Published: March 2007

Associate EditorMichael G. WyllieEditorial BoardIan Eardley, UKJean Fourcroy, USASidney Glina, BrazilJulia Heiman, USAChris McMahon, AustraliaBob Millar, UKAlvaro Morales, CanadaMichael Perelman, USAMarcel Waldinger, NetherlandsOBJECTIVETo assess the influence of vardenafil on treatment satisfaction in men with erectile dysfunction (ED) and their female partners.PATIENTS AND METHODSThis was a pooled analysis of three randomized, double‐blind, placebo‐controlled, 12‐week studies of flexible‐dose vardenafil vs placebo, in men with ED for ≥6 months (n = 788) and their untreated female partners. Measures of efficacy included the Treatment Satisfaction Scale (TSS), International Index of Erectile Function, Erectile Function domain (IIEF‐EF), and Sexual Encounter Profile (SEP) questions 2 and 3 (SEP‐2, ‘Were you able to insert your penis into your partner’s vagina?’; and SEP‐3, ‘Did your erection last long enough for you to have sexual intercourse?’). In addition to the overall analysis, there was a subgroup analysis for potential moderators of response, e.g. whether patients who had undergone previous phosphodiesterase type 5 (PDE‐5) treatment.RESULTSAt baseline, least‐squares (LS) mean scores for all TSS domains were similar in the vardenafil and placebo groups. After 12  weeks of treatment, vardenafil significantly improved the LS mean score for all domains compared with placebo, among both patients and their female partners (P < 0.0001, ‘last’‐observation‐carried‐ forward analysis). Absolute between‐ group differences in LS mean TSS scores (vardenafil − placebo) were: ease of erection (patients 23.4, partners 24.9), erectile function satisfaction (36.7 and 32.9), pleasure from sexual activity (23.0, 23.7), satisfaction with orgasm (27.6, 21.8), confidence to complete sexual activity (28.2, 32.5), and satisfaction with medication (37.4, 35.6). The benefits of vardenafil were greater in men who had undergone previous PDE‐5‐inhibitor treatment and men aged <45 years, while the overall pattern of benefit was similar in all examined subgroups. There were significant benefits with vardenafil in all other variables (IIEF‐EF scores and positive response rates to SEP‐2 and SEP‐3).ConClusionsVardenafil significantly improved treatment satisfaction in men with ED, and in their partners. The results provide further evidence of the validity of the TSS.
Interaction of mixture of anionic surfactants with collagen
Authors: Krejčí J. 
Published: March 2007

SynopsisStudy focused on interaction of collagen fibres of collagen I with anionic surfactants sodium dodecylbenzene sulphonate (SDBS), sodium dodecyl sulphate (SDS) and their mixtures at pH = 6, at two ionic strengths (I = 0.06 mol L−1and I = 0.4 mol  L−1) and laboratory temperature. Surfactants and their mixtures were characterised by their critical micelle concentration (c.m.c.), composition of mixed micelles and interaction factor β according to Rubingh. Dependency of c.m.c. on mixture composition has an opposite tendency at both ionic strengths, which proves the greater influence of added electrolyte on behaviour of SDS than of SDBS. Interaction was evaluated by means of binding isotherms and mass swelling degree αm. The bound quantity partly depends on mixture composition, partly on ionic strength. SDS and mixtures containing its greater quantities are bound more than SDBS (approx. 150% related to SDBS). Increased ionic strength of the environment increases bound quantity in approximately same manner, heedless of adsorbate composition. Even composition of the mixture after interaction with fibres does not markedly alter from initial composition. Fibre swelling is affected by composition of swelling mixture similarly to binding – it increases with growing quantity of surfactants. Greater ionic strength acts against collagen swelling, and at given ionic strength (I = 0.4 mol  L−1) swelling attains half values compare to swelling at low ionic strength (I = 0.06 mol L−1). There are characteristic concentrations of both surfactants and their mixtures (cs ∼ 0.5 ‐ 1.0 mmol L−1) that do not produce swelling. It is assumed that this range of concentrations corresponds to amount of surfactants bound to collagen through electrostatic forces and thus to temporary increase in fibre hydrophobity.
The PorGrow project – an introduction and overview
Authors: Millstone E. , Lobstein T. ,   the PorGrow national teams
Published: March 2007

SummaryObesity in Europe is reaching epidemic proportions, and Europe’s policymakers need more information on the approaches that stakeholders judge effective and consider acceptable. The Policy Options for Responding to the Growing Challenge of Obesity Research Project interviewed food producers, manufacturers and retailers, advertisers and caterers, life insurers, pharmaceutical companies, teachers, public health experts, town planners, advocacy organizations and consumer groups in nine countries: Cyprus, Finland, France, Greece, Hungary, Italy, Poland, Spain and the UK. Interviews were conducted using innovative Multi‐Criteria Mapping software which provides reproducible and transparent structured information on the stakeholders’ perceptions, judgements and reasons. The results indicate that a comprehensive portfolio of policy measures, integrated into a coherent programme, would be well‐supported by a broad coalitions of stakeholders. The costs of such a programme were not considered as important as the potential costs of not taking action. Policymakers can be confident that the great majority of stakeholders recognize the need for action and are prepared to accept their costs, but that the ‘upstream’ interventions such as marketing controls, planning and transport controls and fiscal measures, will need to be justified in terms of their wider health and social benefits.
Stakeholder appraisal of policy options for responding to obesity in Hungary
Authors: Horváth Z. , Pankotai M. G. , Szabolcs I. 
Published: March 2007

SummaryOverweight and obesity increases risks for many diseases, while treating them is expensive. Trends in the prevalence of overweight and obesity over the last two decades indicate the need for urgent interventions. Several different kinds of interventions could modify the obesogenic environment. The aim of this study was to map which policy options will be acceptable and effective in Hungary. Interviews were conducted with 21 stakeholders representing a wide range of viewpoints to evaluate seven core and 13 discretionary policy options under different criteria. The 21 Hungarian participants used 92 appraisal criteria covering a wide range of issues. Efficacy, practical feasibility, social acceptability and societal benefits were widely judged more important than the costs of measures. Significant additional social and health benefits were anticipated from changes in transport and planning policies, but the cost to the public sector was considered high and the implementation difficult. There was broad support for changes in patterns of food consumption and levels of physical activity. There was a consensus that without developing the attitudes of individuals to be more responsible for their health, environmental changes alone would not be enough to reverse the trend of the growing prevalence of obesity.