bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lessepsian fish migration: genetic bottlenecks and parasitological evidence
Authors: Merella Paolo , Casu Marco , Garippa Giovanni , Pais Antonio 
Published: February 2010

AbstractAs a rule, non‐indigenous species (NIS) populations derived from biological invasion events represent a subset of the genetic diversity of the source population. In biological invasions, host–parasite interactions play an important role, and parasitological data for NIS populations can provide useful information such as their area of origin, mechanism of invasion and prospects of success in the new habitat. When both genetic and parasitological data are available, and they suggest the same scenario, the history of an invasion can be inferred with no discrepancy, but when data cannot be reconciled an alternative model should be considered. In this study a comparison of genetic and parasitological data for the Lessepsian migrant the bluespotted cornetfish, Fistularia commersonii, in the Mediterranean Sea presents the opportunity to evaluate the compatibility of information of this nature, and to propose possible invasion scenarios consistent with evidence provided by both criteria.
A dual role of extracellular DNA during biofilm formation of Neisseria meningitidis
Authors: Lappann Martin , Claus Heike , Van Alen Tessa , Harmsen Morten , Elias Johannes , Molin Søren , Vogel Ulrich 
Published: February 2010

SummaryMajor pathogenic clonal complexes (cc) of Neisseria meningitidis differ substantially in their point prevalence among healthy carriers. We show that frequently carried pathogenic cc (e.g. sequence type ST‐41/44 cc and ST‐32 cc) depend on extracellular DNA (eDNA) to initiate in vitro biofilm formation, whereas biofilm formation of cc with low point prevalence (ST‐8 cc and ST‐11 cc) was eDNA‐independent. For initial biofilm formation, a ST‐32 cc type strain, but not a ST‐11 type strain, utilized eDNA. The release of eDNA was mediated by lytic transglycosylase and cytoplasmic N‐acetylmuramyl‐l‐alanine amidase genes. In late biofilms, outer membrane phospholipase A‐dependent autolysis, which was observed in most cc, but not in ST‐8 and ST‐11 strains, was required for shear force resistance of microcolonies. Taken together, N. meningitidis evolved two different biofilm formation strategies, an eDNA‐dependent one yielding shear force resistant microcolonies, and an eDNA‐independent one. Based on the experimental findings and previous epidemiological observations, we hypothesize that most meningococcal cc display a settler phenotype, which is eDNA‐dependent and results in a stable interaction with the host. On the contrary, spreaders (ST‐11 and ST‐8 cc) are unable to use eDNA for biofilm formation and might compensate for poor colonization properties by high transmission rates.
Expression and maintenance of ComD–ComE, the two‐component signal‐transduction system that controls competence of Streptococcus pneumoniae
Authors: Martin Bernard , Granadel Chantal , Campo Nathalie , Hénard Vincent , Prudhomme Marc , Claverys Jean‐Pierre 
Published: February 2010

SummaryA secreted competence‐stimulating peptide (CSP), encoded by comC, constitutes, together with the two‐component system ComD‐ComE, the master switch for competence induction in Streptococcus pneumoniae. Interaction between CSP and its membrane‐bound histidine‐kinase receptor, ComD, is believed to lead to autophosphorylation of ComD, which then transphosphorylates the ComE response regulator to activate transcription of a limited set of genes, including the comCDE operon. This generates a positive feedback loop, amplifying the signal and co‐ordinating competence throughout the population. On the other hand, the promoter(s) and proteins important for basal comCDE expression have not been defined. We now report that CSP‐induced and basal comCDE transcription both initiate from the same promoter, PE; that basal expression necessitates the presence of both ComD and a phosphate‐accepting form of ComE, but not CSP; and that overexpression of ComER120S triggers ComD‐dependent transformation in the absence of CSP. These observations suggest that self‐activation of ComD is required for basal comCDE expression. We also establish that transcriptional readthrough occurs across the tRNAArg5 terminator and contributes significantly to comCDE expression. Finally, we demonstrate by various means, including single‐cell competence analysis with GFP, that readthrough is crucial to avoid the stochastic production of CSP non‐responsive cells lacking ComD or ComE.
The IsdG‐family of haem oxygenases degrades haem to a novel chromophore
Authors: Reniere Michelle L. , Ukpabi Georgia N. , Harry S. Reese , Stec Donald F. , Krull Robert , Wright David W. , Bachmann Brian O. , Murphy Michael E. , Skaar Eric P. 
Published: February 2010

SummaryEnzymatic haem catabolism by haem oxygenases is conserved from bacteria to humans and proceeds through a common mechanism leading to the formation of iron, carbon monoxide and biliverdin. The first members of a novel class of haem oxygenases were recently identified in Staphylococcus aureus (IsdG and IsdI) and were termed the IsdG‐family of haem oxygenases. Enzymes of the IsdG‐family form tertiary structures distinct from those of the canonical haem oxygenase family, suggesting that IsdG‐family members degrade haem via a unique reaction mechanism. Herein we report that the IsdG‐family of haem oxygenases degrade haem to the oxo‐bilirubin chromophore staphylobilin. We also present the crystal structure of haem‐bound IsdI in which haem ruffling and constrained binding of oxygen is consistent with cleavage of the porphyrin ring at the β‐ or δ‐meso carbons. Combined, these data establish that the IsdG‐family of haem oxygenases degrades haem to a novel chromophore distinct from biliverdin.
Inactivation of a putative flagellar motor switch protein FliG1 prevents Borrelia burgdorferi from swimming in highly viscous media and blocks its infectivity
Authors: Li Chunhao , Xu Hongbin , Zhang Kai , Liang Fang Ting 
Published: February 2010

SummaryThe flagellar motor switch complex protein FliG plays an essential role in flagella biosynthesis and motility. In most motile bacteria, only one fliG homologue is present in the genome. However, several spirochete species have two putative fliG genes (referred to as fliG1 and fliG2) and their roles in flagella assembly and motility remain unknown. In this report, the Lyme disease spirochete Borrelia burgdorferi was used as a genetic model to investigate the roles of these two fliG homologues. It was found that fliG2 encodes a typical motor switch complex protein that is required for the flagellation and motility of B. burgdorferi. In contrast, the function of fliG1 is quite unique. Disruption of fliG1 did not affect flagellation and the mutant was still motile but failed to translate in highly viscous media. GFP‐fusion and motion tracking analyses revealed that FliG1 asymmetrically locates at one end of cells and the loss of fliG1 somehow impacted one bundle of flagella rotation. In addition, animal studies demonstrated that the fliG1− mutant was quickly cleared after inoculation into the murine host, which highlights the importance of the ability to swim in highly viscous media in the infectivity of B. burgdorferi and probably other pathogenic spirochetes.
Beliefs and beyond: what can we learn from qualitative studies of lay people’s understandings of cancer risk?
Authors: Lipworth Wendy L. , Davey Heather M. , Carter Stacy M. , Hooker Claire , Hu Wendy 
Published: February 2010

AbstractBackground  Clinicians and public health professionals are centrally concerned with mediating risk. However, people often resist the risk‐related information that is communicated to them by experts, or have their own models of risk that conflict with expert views. Quantitative studies have clearly demonstrated the importance of health beliefs and various cognitive and emotional processes in shaping risk perception. More recently, a growing body of qualitative research has emerged, exploring lay conceptualizations, experiences and constructions of cancer risk. To date, this literature has not been synthesized.Objective  We report the findings of a synthesis of qualitative literature regarding the ways in which lay people construct and experience cancer risk.Design  We identified 87 articles and used the method of ‘thematic synthesis’ to identify and interpret key concepts from existing studies.Results  Eight analytic categories were developed: (i) perceptions of risk factors; (ii) process of risk perception; (iii) seeking control and taking responsibility (motivational factors); (iv) experiencing cancer directly; (v) constructing risk temporally; (vi) embodying risk; (vii) identifying with risk; and (viii) constructing risk in a social context.Conclusions  Qualitative enquiry can provide us with a rich and nuanced picture of the ways in which people understand, experience and construct risk and how being ‘at risk’ is managed, and can assist us in our communication with both individual patients and populations.
Diagnostic value of exhaled nitric oxide in childhood asthma and allergy
Authors: Sachs‐Olsen C. , Lødrup Carlsen K. C. , Mowinckel P. , Håland G. , Devulapalli C. S. , Munthe‐Kaas M. C. , Carlsen K.‐H. 
Published: February 2010

Sachs‐Olsen C, Lødrup Carlsen KC, Mowinckel P, Håland G, Devulapalli CS, Munthe‐Kaas MC, Carlsen K‐H. Diagnostic value of exhaled nitric oxide in childhood asthma and allergy. Pediatr Allergy Immunol 2010: 21: e213–e221. © 2010 John Wiley & Sons A/SFractional exhaled nitric oxide (FENO) has been proposed as a diagnostic test of asthma. We aimed to investigate in a population based birth cohort of children the usefulness of FENO as a diagnostic tool. The 10‐yr follow up of the Environment and Childhood Asthma Study in Oslo included 616 children representative of the prospective birth cohort. Both FENO (single breath technique) and skin prick test (SPT) were measured in 331, limited at the time by equipment availability. Structural parental interview, spirometry, methacholine challenge and exercise test were performed. FENO was significantly elevated in children with current asthma (geometric mean 9.6 (95% confidence interval (CI) (6.9, 13.4) p.p.b.) compared with healthy children (5.8 (5.4, 6.3) p.p.b.; p < 0.001). FENO was highest among children with current allergic asthma (asthma and positive SPT) (14.0 (8.9, 22.1) p.p.b.), whereas children with non‐allergic asthma (6.1 (4.0, 9.2) p.p.b.) had comparable FENO levels to healthy children (p = 0.99). Allergic sensitization was most closely associated with FENO. A FENO cut‐off value of 20.4 p.p.b. had a high specificity (0.97), but a low sensitivity (0.41) and a Positive Likelihood Ratio of 16.1 for current allergic asthma. In the present childhood population‐based study, high FENO levels were closely associated with current allergic asthma and not with current asthma without allergic sensitization. Estimating the individual predictive probability of having asthma by use of FENO, improves the diagnostic utility of the test.
Variation in virulence of Cryphonectria hypovirus 1 in Macedonia
Authors: Sotirovski K. , Rigling D. , Heiniger U. , Milgroom M. G. 
Published: February 2010

SummaryWe investigated variation in virulence of Cryphonectria hypovirus 1 (CHV‐1) to the chestnut blight fungus, Cryphonectria parasitica, in Macedonia by inoculating chestnut stems in the field. We inoculated trees with two isolates of C. parasitica, each infected with one of five isolates of CHV‐1, four of which were the same for both fungal isolates. Two virus isolates, [Sk28] and [Sk47], were significantly more virulent than the others when compared in the same fungal host isolates, as measured by reduced canker growth and increased callus formation. Mycelial growth rate in vitro was weakly correlated to canker growth or callus formation and is therefore not a reliable predictor for virulence. We found significant fungus × virus interactions for canker growth and callus formation, which seems due mainly to one virus isolate. Significant interactions were not expected because the two fungal host isolates are members of the same clone that is dominant in Macedonia and most of southeastern Europe. Phenotypic variation for response to viruses, therefore, is greater than variation revealed by the genetic markers used to define clones. More than half of the trees inoculated with virus‐free controls were dead within 2 years, and the 30% still alive after 5 years had cankers with extensive callus formation, indicating that natural virus transmission had occurred after inoculation. In contrast, only 2% of the trees inoculated with virus‐infected isolates were dead after 5 years. Hypoviruses naturally occurring in Macedonia reduce canker development and tree mortality similarly to those in other parts of southern Europe, and therefore, may have good potential for biological control of chestnut blight.
DNA markers to disentangle complexes of cryptic taxa in mealybugs (Hemiptera: Pseudococcidae)
Authors: Malausa T. , Fenis A. , Warot S. , Germain J.‐F. , Ris N. , Prado E. , Botton M. , Vanlerberghe‐Masutti F. , Sforza R. , Cruaud C. , Couloux A. , Kreiter P. 
Published: February 2010

AbstractMealybugs (Hemiptera: Pseudococcidae) are major pests of a wide range of crops and ornamental plants worldwide. Their high degree of morphological similarity makes them difficult to identify and limits their study and management. We aimed to identify a set of markers for the genetic characterization and identification of complexes of taxa in the Pseudococcidae. We surveyed and tested the genetic markers used in previous studies and then identified new markers for particularly relevant genomic regions for which no satisfactory markers were available. We tested all markers on a subset of four taxa distributed worldwide. Five markers were retained after this first screening: two regions of the mitochondrial cytochrome oxidase I gene, 28S‐D2, the entire internal transcriber space 2 locus and the rpS15‐16S region of the primary mealybug endosymbiont Tremblaya princeps. We then assessed the utility of these markers for the characterization and identification of 239 samples from 43 sites in France and Brazil. The five markers studied (i) successfully distinguished all species identified by morphological examination, (ii) disentangled complexes of species by revealing intraspecific genetic variation and identified a set of closely related taxa for which taxonomic status requires clarification through further studies, and (iii) facilitated the inference of phylogenetic relationships between the characterized taxa.
C1 inhibitor level on neonatal sepsis and its relations with clinical findings
Authors: Tapisiz Anil , Ergenekon Ebru , Oktem Murat , Koc Esin , Okumus Nurullah , Zenciroğlu Aysegül , Atalay Yıldız 
Published: February 2010

Background:  Generalised oedema is a frequent finding during neonatal sepsis, but its aetiology remains uncertain.Objective:  The objective of this study was to measure functional C1 inhibitor (fC1 inh) levels in newborns with culture‐proven sepsis, compare the results with age‐ and gestational age (GA)‐matched controls and correlate the results with the clinical course of the patients during infection, with regard to vascular leak and oedema formation.Methods:  Newborns with blood culture‐proven sepsis were included and samples for C1 inh levels were obtained before the beginning of antibiotic therapy and on the 3rd day of treatment. Body weight, urine output and other treatment modalities including volume boluses were recorded. Oedema formation as a sign of vascular leak was determined by calculating percent weight change over time. Age‐ and GA‐matched newborns without infection were used as controls.Results:  No difference was observed between the patient and the control groups concerning fC1 inh levels. Percent weight change in the patient group was not correlated with the C1 inh levels.Conclusion:  Despite studies suggesting the role of C1 inhibitor deficiency in vascular leak during sepsis in adults, there is no information in the literature regarding the C1 inh levels of healthy or septic newborns to date. In this study, fC1 inh levels were no different than controls, necessitating the consideration of other factors causing vascular leak and oedema during neonatal sepsis.
Corticosteroid insensitivity in severe asthma: significance, mechanisms and aetiology
Authors: Hew M. , Chung K. F. 
Published: February 2010

AbstractChronic severe asthma remains a challenging clinical problem despite the availability of modern treatments. Relative corticosteroid insensitivity is present in severe asthma and may contribute to continuing disease severity. Advances in the understanding of molecular mechanisms underlying corticosteroid insensitivity may yield new therapeutic targets. Furthermore, aetiological factors for corticosteroid insensitivity have been identified and these may be amenable to modification.
Acute care costs of patients admitted for management of chronic obstructive pulmonary disease exacerbations: contribution of disease severity, infection and chronic heart failure
Authors: Hutchinson A. , Brand C. , Irving L. , Roberts C. , Thompson P. , Campbell D. 
Published: February 2010

AbstractBackground: In 2003, chronic obstructive pulmonary disease (COPD) accounted for 46% of the burden of chronic respiratory disease in the Australian community. In the 65–74‐year‐old age group, COPD was the sixth leading cause of disability for men and the seventh for women.Aims: To measure the influence of disease severity, COPD phenotype and comorbidities on acute health service utilization and direct acute care costs in patients admitted with COPD.Methods: Prospective cohort study of 80 patients admitted to the Royal Melbourne Hospital in 2001–2002 for an exacerbation of COPD. Patients were followed for 12 months and data were collected on acute care utilization. Direct hospital costs were derived using Transition II, an activity‐based costing system. Individual patient costs were then modelled to ascertain which patient factors influenced total direct hospital costs.Results: Direct costs were calculated for 225 episodes of care, the median cost per admission was AU$3124 (interquartile range $1393 to $5045). The median direct cost of acute care management per patient per year was AU$7273 (interquartile range $3957 to $14 448). In a multivariate analysis using linear regression modelling, factors predictive of higher annual costs were increasing age (P= 0.041), use of domiciliary oxygen (P= 0.008) and the presence of chronic heart failure (P= 0.006).Conclusion: This model has identified a number of patient factors that predict higher acute care costs and awareness of these can be used for service planning to meet the needs of patients admitted with COPD.
Which model for propofol TCI in children
Authors: CONSTANT ISABELLE , RIGOUZZO AGNES 
Published: February 2010

SummaryFor several years, total intravenous anesthesia (TIVA) has demonstrated many advantages that allow consideration of propofol anesthesia as an interesting alternative in pediatric anesthesia. TIVA in children requires calculation and validation of pharmacokinetic (PK) models specifically adapted to the pediatric population. Several PK models based on a 3‐compartment approach have been proposed in children: all these models, which integrate only weight as covariable, show increased distribution volumes with a wide interindividual variability. However, as pharmacodynamic (PD) parameters are still debated in children, there is up to now, no PKPD model currently available for pediatric anesthesia. The particular importance to include physiological covariables, as size and age, to describe metabolic processes during growth and maturation in pediatric PKPD models is in agreement with recent allometric scaling works in children. The Schnider’s model, a model described in adults that includes numerous covariables, may be adapted and more efficient than the classical pediatric model to describe propofol–PKPD relationship in children over 5 years. Whatever is the model, a pharmacodynamic feed back such as the bispectral index may be useful to counteract the interindividual variability in the pediatric population.
Internet‐based information‐seeking behaviour amongst doctors and nurses: a short review of the literature
Authors: Younger Paula 
Published: February 2010

AbstractBackground:  Reviews of how doctors and nurses search for online information are relatively rare, particularly where research examines how they decide whether to use Internet‐based resources. Original research into their online searching behaviour is also rare, particularly in real world clinical settings. as is original research into their online searching behaviour. This review collates some of the existing evidence, from 1995 to 2009.Objectives:  To establish whether there are any significant differences in the ways and reasons why doctors and nurses seek out online information; to establish how nurses and doctors locate information online; to establish whether any conclusions can be drawn from the existing evidence that might assist health and medical libraries in supporting users.Methods:  An initial scoping literature search was carried out on PubMed and CINAHL to identify existing reviews of the subject area and relevant original research between 1995 and 2009. Following refinement, further searches were carried out on Embase (Ovid), LISA and LISTA. Following the initial scoping search, two journals were identified as particularly relevant for further table of contents searching. Articles were exclused where the main focus was on patients searching for information or where the focus was the evaluation of online‐based educational software or tutorials. Articles were included if they were review or meta‐analysis articles, where they reported original research, and where the primary focus of the online search was for participants’ ongoing Continuing Professional Development (CPD). The relevant articles are outlined, with details of numbers of participants, response rates, and the user groups.Results:  There appear to be no significant differences between the reasons why doctors and nurses seek online Internet‐based evidence, or the ways in which they locate that evidence. Reasons for searching for information online are broadly the same: primarily patient care and CPD (Continuing Professional Development). The perceived barriers to accessing online information are the same in both groups. There is a lack of awareness of the library as a potential online information enabler.Conclusions:  Libraries need to examine their policy and practice to ensure that they facilitate access to online evidence‐based information, particularly where users are geographically remote or based in the community rather than in a hospital setting. Librarians also need to take into account the fact that medical professionals on duty may not be able to take advantage of the academic model of online information research. Further research is recommended into the difference between the idealised academic model of searching and real world practicalities; and how other user groups search, for example patients.