bluuebunny/crossref_metadata_2025 huggingface dataset:
Restricted gene flow in the endangered pygmy bluetongue lizard (Tiliqua adelaidensis) in a fragmented agricultural landscape
Authors: Smith Annabel L. , Gardner Michael G. , Fenner Aaron L. , Bull C. Michael
Published: September 2009

Habitat fragmentation can have several adverse genetic impacts on populations. Assessing the extent of these threatening processes is essential in conservation management. In the present study, we investigated the genetic population structure of the endangered pygmy bluetongue lizard, Tiliqua adelaidensis, which is now restricted to a few small fragments of its previously more extensive grassland habitat. The aim of our study was to investigate genetic diversity and gene flow both among and within sample sites. The information will assist in making recommendations for habitat conservation and translocation programs. We collected DNA from 229 individuals from six isolated sample sites and genotyped them for 16 polymorphic microsatellite loci. Across all six sample sites, observed heterozygosity ranged from 0.75 to 0.82. There was no evidence of population bottlenecks and little evidence of inbreeding due to consanguineous mating. Genetic differentiation was low to moderate although significant for all pairs of sample sites (FST = 0.021–0.091). Results from Bayesian clustering analyses revealed distinct clusters in the overall sample and suggested restricted gene flow between sample sites separated by distances ranging from 1.7 to 71.6 km. By using spatial autocorrelation, we also found a significant genetic structure within sample sites at distances up to 30 m, suggesting restricted gene flow even in small patches of continuous habitat. It will be important to preserve this finely clustered population structure in captive breeding and translocation programs. Increasing opportunities for gene flow through habitat corridors or population augmentation may help maintain genetic diversity and prevent an increase in differentiation. Although endangered species do not always present model systems for studying fragmentation, our approach shows how important genetic information can be acquired to aid conservation in highly fragmented ecosystems.
How oxygen attacks [FeFe] hydrogenases from photosynthetic organisms
Authors: Stripp Sven T. , Goldet Gabrielle , Brandmayr Caterina , Sanganas Oliver , Vincent Kylie A. , Haumann Michael , Armstrong Fraser A. , Happe Thomas
Published: September 2009

Green algae such as
Chlamydomonas reinhardtii
synthesize an [FeFe] hydrogenase that is highly active in hydrogen evolution. However, the extreme sensitivity of [FeFe] hydrogenases to oxygen presents a major challenge for exploiting these organisms to achieve sustainable photosynthetic hydrogen production. In this study, the mechanism of oxygen inactivation of the [FeFe] hydrogenase
Cr
HydA1 from
C. reinhardtii
has been investigated. X-ray absorption spectroscopy shows that reaction with oxygen results in destruction of the [4Fe-4S] domain of the active site H-cluster while leaving the di-iron domain (2Fe
H
) essentially intact. By protein film electrochemistry we were able to determine the order of events leading up to this destruction. Carbon monoxide, a competitive inhibitor of
Cr
HydA1 which binds to an Fe atom of the 2Fe
H
domain and is otherwise not known to attack FeS clusters in proteins, reacts nearly two orders of magnitude faster than oxygen and protects the enzyme against oxygen damage. These results therefore show that destruction of the [4Fe-4S] cluster is initiated by binding and reduction of oxygen at the di-iron domain—a key step that is blocked by carbon monoxide. The relatively slow attack by oxygen compared to carbon monoxide suggests that a very high level of discrimination can be achieved by subtle factors such as electronic effects (specific orbital overlap requirements) and steric constraints at the active site.
Costly punishment does not always increase cooperation
Authors: Wu Jia-Jia , Zhang Bo-Yu , Zhou Zhen-Xing , He Qiao-Qiao , Zheng Xiu-Deng , Cressman Ross , Tao Yi
Published: September 2009

In a pairwise interaction, an individual who uses costly punishment must pay a cost in order that the opponent incurs a cost. It has been argued that individuals will behave more cooperatively if they know that their opponent has the option of using costly punishment. We examined this hypothesis by conducting two repeated two-player Prisoner's Dilemma experiments, that differed in their payoffs associated to cooperation, with university students from Beijing as participants. In these experiments, the level of cooperation either stayed the same or actually decreased when compared with the control experiments in which costly punishment was not an option. We argue that this result is likely due to differences in cultural attitudes to cooperation and punishment based on similar experiments with university students from Boston that found cooperation did increase with costly punishment.
Unraveling different chemical fingerprints between a champagne wine and its aerosols
Authors: Liger-Belair Gérard , Cilindre Clara , Gougeon Régis D. , Lucio Marianna , Gebefügi Istvan , Jeandet Philippe , Schmitt-Kopplin Philippe
Published: September 2009

As champagne or sparkling wine is poured into a glass, the myriad of ascending bubbles collapse and radiate a multitude of tiny droplets above the free surface into the form of very characteristic and refreshing aerosols. Ultrahigh-resolution MS was used as a nontargeted approach to discriminate hundreds of surface active compounds that are preferentially partitioning in champagne aerosols; thus, unraveling different chemical fingerprints between the champagne bulk and its aerosols. Based on accurate exact mass analysis and database search, tens of these compounds overconcentrating in champagne aerosols were unambiguously discriminated and assigned to compounds showing organoleptic interest or being aromas precursors. By drawing a parallel between the fizz of the ocean and the fizz in Champagne wines, our results closely link bursting bubbles and flavor release; thus, supporting the idea that rising and collapsing bubbles act as a continuous paternoster lift for aromas in every glass of champagne.
Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age
Authors: Johnston D. T. , Wolfe-Simon F. , Pearson A. , Knoll A. H.
Published: September 2009

Molecular oxygen (O
2
) began to accumulate in the atmosphere and surface ocean ca. 2,400 million years ago (Ma), but the persistent oxygenation of water masses throughout the oceans developed much later, perhaps beginning as recently as 580–550 Ma. For much of the intervening interval, moderately oxic surface waters lay above an oxygen minimum zone (OMZ) that tended toward euxinia (anoxic and sulfidic). Here we illustrate how contributions to primary production by anoxygenic photoautotrophs (including physiologically versatile cyanobacteria) influenced biogeochemical cycling during Earth's middle age, helping to perpetuate our planet's intermediate redox state by tempering O
2
production. Specifically, the ability to generate organic matter (OM) using sulfide as an electron donor enabled a positive biogeochemical feedback that sustained euxinia in the OMZ. On a geologic time scale, pyrite precipitation and burial governed a second feedback that moderated sulfide availability and water column oxygenation. Thus, we argue that the proportional contribution of anoxygenic photosynthesis to overall primary production would have influenced oceanic redox and the Proterozoic O
2
budget. Later Neoproterozoic collapse of widespread euxinia and a concomitant return to ferruginous (anoxic and Fe
2+
rich) subsurface waters set in motion Earth's transition from its prokaryote-dominated middle age, removing a physiological barrier to eukaryotic diversification (sulfide) and establishing, for the first time in Earth's history, complete dominance of oxygenic photosynthesis in the oceans. This paved the way for the further oxygenation of the oceans and atmosphere and, ultimately, the evolution of complex multicellular organisms.
The evolution of the English-language speech community in Hong Kong
Authors: Evans Stephen
Published: October 2009

This article traces the evolution of the English-language speech community in Hong Kong since the early 1840s. Inspired by Schneider’s (2007) innovative “Dynamic Model”, the article examines textual and statistical data derived from a range of hitherto unexploited archival sources, including a historical corpus of English-language newspapers, confidential Colonial Office correspondence, and government records. Changes in the size and composition of the English-language speech community are tracked through a diachronic analysis of government censuses, school enrolments, lists of jurors, and letters to the press. The results of this analysis support Schneider’s contention that the 1960s marked an important turning point in Hong Kong’s linguistic history in that it presaged a substantial, education-driven increase in the numbers and proportion of English users in the territory. Despite the significant expansion of the English-using community in the past four decades, the dominant theme of public discourse about English has been that of “declining standards”. While the existence of a “complaint tradition” accords with the predictions of the Dynamic Model, it is perhaps not widely known that this tradition is a long-standing one. The present article traces this tradition back to the era of the Opium Wars.
Effectiveness Study of Venlafaxine-XR Combined with Aripiprazole for Chronic or Recurrent Major Depressive Disorder
Authors: Nierenberg Andrew A. , Trivedi Madhukar H. , Gaynes Bradley N. , Mitchell Jeff , Davis Lori L. , Husain Mustafa M. , Wisniewski Stephen R. , Fava Maurizio , Warden Diane , Luther James F. , van Nieuwenhuizen Adrienne O. , Morris David W. , Shelton Richard C. , John Rush A.
Published: October 2009

Objective: Although the second-generation antipsychotic, aripiprazole (ARI), has been approved as an adjunct for treatment-resistant major depressive disorder (MDD), neither ARI nor any second-generation antipsychotic has been assessed in combination with an antidepressant at the initiation of a treatment trial for non-treatment-resistant MDD. The aim of the present study was therefore to assess the safety, tolerability, and remission rate in the treatment of MDD using the specific combination of venlafaxine-XR (VEN-XR) and ARI in a generalizable, difficult-to-treat group with chronic or recurrent MDD.

Methods: Self-declared participants in primary care or psychiatric settings who had chronic or recurrent MDD and a minimum score of 14 on the 17-item Hamilton Rating Scale for Depression were included. Up to 12 weeks of open treatment with the combination of VEN-XR and ARI was provided. Participants began with VEN-XR, and ARI was added at week 2. Maximum allowable doses were 300 mg day–1 for venlafaxine-XR and 30 mg day–1 for ARI. Remission was defined as ≤ 5 on the 16-item Quick Inventory of Depressive Symptomatology–Self-report (QIDS-SR16).

Results: Fifty outpatients with non-psychotic MDD were enrolled (mean age = 43±11 years; 38% male; QIDS-SR16=15±3). Mean exit dose of VEN-XR was 227±97 mg day–1, and the mean exit dose of ARI was 11±7 mg day–1. The combination was well tolerated; 16% of participants discontinued due to side-effects. Approximately 70% achieved remission at some point during the trial, and 66% achieved remission at study exit.

Conclusions: To the best of the authors’ knowledge this is the first study to combine an antidepressant and second-generation antipsychotic at the beginning of a treatment trial for chronic or recurrent non-treatment resistant MDD. VEN-XR and ARI combination appears to warrant further study in controlled trials.
Social Anxiety Disorder: Recent Developments in Psychological Approaches to Conceptualization and Treatment
Authors: Lampe Lisa Anne
Published: October 2009

The aim of the present study was to identify and synthesize recent research findings in the aetiology and psychological treatment of social anxiety disorder and consider how these might improve outcome through more effective intervention. The electronic databases Medline, EMBASE and PsychInfo were searched for January 2000–December 2008. Publications of interest referred to in relevant articles were also reviewed. Case reports and publications not in English were excluded. The greatest variance in social anxiety disorder is accounted for by temperamental and personality factors and these may be associated with significant heritability. The environmental contribution is smaller and mainly due to non-shared factors, with a small contribution from shared environmental factors. Epidemiological research confirms that social anxiety disorder is chronic, and among the anxiety disorders has the lowest rates of treatment seeking, receipt of evidence-based treatments and recovery. Effective psychological treatments have been available for some time, and the research emphasis is on increasing the efficacy of treatments through innovations in programme content and delivery. Cognitive science research has contributed a better understanding of cognitive factors that maintain social anxiety disorder and informed enhancement of the cognitive elements of therapy. Internet-based programmes show promise as a novel way to deliver and improve access to effective therapy. Genetic, personality and temperamental factors contribute to the risk for social anxiety disorder. Given the associated comorbidity and disability, energy needs to be directed towards early recognition and treatment, and to increasing engagement and retention in effective therapy. Ongoing professional education is required to ensure that the disorder is recognized and evidence-based treatments received by patients who do seek help. Current cognitive behavioural treatments are being enhanced as the results of cognitive science research are being applied, and novel forms of treatment delivery show promise in increasing access.
Randomized Controlled Trial of Web-Based Treatment of Social Phobia Without Clinician Guidance
Authors: Titov Nickolai , Andrews Gavin , Choi Isabella , Schwencke Genevieve , Johnston Luke
Published: October 2009

Objective: The aim of the present study was (Shyness 4) to determine which level of reminder best facilitated a clinician-free Internet treatment for social phobia.

Method: A pragmatic randomized controlled trial of an enhanced Internet treatment, with and without weekly telephone reminders, was done. Participants consisted of 163 volunteers with social phobia, who completed six lessons of computerized cognitive behaviour therapy for social phobia with complex automated reminders. Main outcome measures were the Social Interaction Anxiety Scale and Social Performance Scale.

Results: Social phobia improved in both groups. Adherence (68% vs 81%) and improvement in social phobia (effect size = 0.86 vs 1.15) was better in the group with the added telephone reminders.

Conclusions: Enhanced Internet-based cognitive behaviour therapy without clinician guidance is a strong treatment for social phobia. Telephone reminders further improve outcome. Because both interventions are effective, it is a pragmatic decision for a practice or a service as to whether the 33% increase in efficacy justifies 1 h of practice nurse or receptionist time.
Clinician-Assisted Internet-Based Treatment is Effective for Generalized Anxiety Disorder: Randomized Controlled Trial
Authors: Titov Nickolai , Andrews Gavin , Robinson Emma , Schwencke Genevieve , Johnston Luke , Solley Karen , Choi Isabella
Published: October 2009

Objective: The aim of the present study was to determine the efficacy of an Internet-based clinician-assisted computerized cognitive behavioural treatment (CaCCBT) programme for generalized anxiety disorder (the Worry programme).

Methods: Forty-eight individuals meeting diagnostic criteria for generalized anxiety disorder (GAD) were randomly assigned to the Worry programme or to a waitlist control group. In the clinician-assisted Worry programme, participants complete six online lessons, weekly homework assignments, receive weekly email contact from a clinical psychologist, and contribute to a moderated online discussion forum with other participants. An intention-to-treat model was used for data analyses. The main outcome measures were Generalized Anxiety Disorder–7 Item Scale (GAD-7) and the Penn State Worry Questionnaire (PSWQ).

Results: A total of 75% of treatment group participants completed all six lessons within the 9 week programme and post-treatment data were collected from 21/24 treatment group and 19/21 control group participants. Treatment group participants reported significantly reduced symptoms of worry as measured on the GAD-7 and PSWQ and reduced symptoms of depression as measured on the Patient Health Questionnaire–9 Item Scale (PHQ-9). Mean within- and between-groups effect sizes (Cohen's d) across the two measures of GAD were 1.3 and 1.1, respectively. Participants found the treatment programme acceptable and satisfactory. The clinician spent a total mean of 130 min per person over the programme.

Conclusions: The Worry programme, the first randomized controlled trial of CaCCBT for GAD, resulted in clinically significant improvements. These results are consistent with literature indicating that Internet-based programmes, when combined with clinical guidance, can significantly reduce the symptoms of common mental disorders.
Expanding Australian Psychiatry Training Settings Beyond Metropolitan Public Hospitals: Background and Issues
Authors: Schweizer Yolanda , Spratt Christine , O'Connor Daniel W.
Published: October 2009

Objective: The aim of this paper is to provide an overview of the rationale behind the expansion of specialist psychiatry training positions outside of major public teaching hospitals, as expounded by the Australian Federal Government's Expanded Settings for Specialist Training (ESST) Program.

Conclusion: Alternative training settings are required to help address the anticipated growth in numbers of medical graduates and to meet the need of psychiatry trainees for greater experience in treating high prevalence mental disorders. To progress the expansion of training settings within psychiatry, it is essential that comprehensive consultation be undertaken to understand the implications of this program for trainees, existing training facilities and expanded setting providers to ensure that all stakeholders, including patients and carers, derive benefit.
THE DETERMINANTS OF YOUTH TEMPORARY EMPLOYMENT IN THE ENLARGED EUROPE
Authors: Baranowska Anna , Gebel Michael
Published: September 2009

This article uses comparative micro data from the 2004 European Union Labour Force Survey (EULFS) for 23 European countries to study the impact of labour market institutions on the youth relative temporary employment probability. We find relatively high temporary employment rates for young workers in all countries but also a large cross-country variation in this respect. The results of multi-level regression analyses confirm that neither employment protection of regular contracts nor its interaction with the level of employment protection of temporary contracts affects the young people's relative risk. Instead, we find a positive association between collective bargaining coverage as a measure of insider–outsider cleavages and the relative temporary employment risk of young persons. These results remain robust even after controlling for macro-structural conditions, such as unemployment rate and business uncertainty.
Contextual cost: When a visual-search target is not where it should be
Authors: Makovski Tal , Jiang Yuhong V.
Published: September 2009

Visual search is often facilitated when the search display occasionally repeats, revealing a contextual-cueing effect. According to the associative-learning account, contextual cueing arises from associating the display configuration with the target location. However, recent findings emphasizing the importance of local context near the target have given rise to the possibility that low-level repetition priming may account for the contextual-cueing effect. This study distinguishes associative learning from local repetition priming by testing whether search is directed toward a target's expected location, even when the target is relocated. After participants searched for a T among Ls in displays that repeated 24 times, they completed a transfer session where the target was relocated locally to a previously blank location (Experiment 1) or to an adjacent distractor location (Experiment 2). Results revealed that contextual cueing decreased as the target appeared farther away from its expected location, ultimately resulting in a contextual cost when the target swapped locations with a local distractor. We conclude that target predictability is a key factor in contextual cueing.
An eIF4E-binding protein regulates katanin protein levels in C. elegans embryos
Authors: Li Wei , DeBella Leah R. , Guven-Ozkan Tugba , Lin Rueyling , Rose Lesilee S.
Published: September 2009

In Caenorhabditis elegans, the MEI-1–katanin microtubule-severing complex is required for meiosis, but must be down-regulated during the transition to embryogenesis to prevent defects in mitosis. A cullin-dependent degradation pathway for MEI-1 protein has been well documented. In this paper, we report that translational repression may also play a role in MEI-1 down-regulation. Reduction of spn-2 function results in spindle orientation defects due to ectopic MEI-1 expression during embryonic mitosis. MEL-26, which is both required for MEI-1 degradation and is itself a target of the cullin degradation pathway, is present at normal levels in spn-2 mutant embryos, suggesting that the degradation pathway is functional. Cloning of spn-2 reveals that it encodes an eIF4E-binding protein that localizes to the cytoplasm and to ribonucleoprotein particles called P granules. SPN-2 binds to the RNA-binding protein OMA-1, which in turn binds to the mei-1 3′ untranslated region. Thus, our results suggest that SPN-2 functions as an eIF4E-binding protein to negatively regulate translation of mei-1.
Coupled myosin VI motors facilitate unidirectional movement on an F-actin network
Authors: Sivaramakrishnan Sivaraj , Spudich James A.
Published: September 2009

Unconventional myosins interact with the dense cortical actin network during processes such as membrane trafficking, cell migration, and mechanotransduction. Our understanding of unconventional myosin function is derived largely from assays that examine the interaction of a single myosin with a single actin filament. In this study, we have developed a model system to study the interaction between multiple tethered unconventional myosins and a model F-actin cortex, namely the lamellipodium of a migrating fish epidermal keratocyte. Using myosin VI, which moves toward the pointed end of actin filaments, we directly determine the polarity of the extracted keratocyte lamellipodium from the cell periphery to the cell nucleus. We use a combination of experimentation and simulation to demonstrate that multiple myosin VI molecules can coordinate to efficiently transport vesicle-size cargo over 10 µm of the dense interlaced actin network. Furthermore, several molecules of monomeric myosin VI, which are nonprocessive in single molecule assays, can coordinate to transport cargo with similar speeds as dimers.
INTS3 controls the hSSB1-mediated DNA damage response
Authors: Skaar Jeffrey R. , Richard Derek J. , Saraf Anita , Toschi Alfredo , Bolderson Emma , Florens Laurence , Washburn Michael P. , Khanna Kum Kum , Pagano Michele
Published: September 2009

Human SSB1 (single-stranded binding protein 1 [hSSB1]) was recently identified as a part of the ataxia telangiectasia mutated (ATM) signaling pathway. To investigate hSSB1 function, we performed tandem affinity purifications of hSSB1 mutants mimicking the unphosphorylated and ATM-phosphorylated states. Both hSSB1 mutants copurified a subset of Integrator complex subunits and the uncharacterized protein LOC58493/c9orf80 (henceforth minute INTS3/hSSB-associated element [MISE]). The INTS3–MISE–hSSB1 complex plays a key role in ATM activation and RAD51 recruitment to DNA damage foci during the response to genotoxic stresses. These effects on the DNA damage response are caused by the control of hSSB1 transcription via INTS3, demonstrating a new network controlling hSSB1 function.
Integration of heterogeneous expression data sets extends the role of the retinol pathway in diabetes and insulin resistance
Authors: Park Peter J. , Kong Sek Won , Tebaldi Toma , Lai Weil R. , Kasif Simon , Kohane Isaac S.
Published: September 2009

Motivation: Type 2 diabetes is a chronic metabolic disease that involves both environmental and genetic factors. To understand the genetics of type 2 diabetes and insulin resistance, the DIabetes Genome Anatomy Project (DGAP) was launched to profile gene expression in a variety of related animal models and human subjects. We asked whether these heterogeneous models can be integrated to provide consistent and robust biological insights into the biology of insulin resistance.

Results: We perform integrative analysis of the 16 DGAP data sets that span multiple tissues, conditions, array types, laboratories, species, genetic backgrounds and study designs. For each data set, we identify differentially expressed genes compared with control. Then, for the combined data, we rank genes according to the frequency with which they were found to be statistically significant across data sets. This analysis reveals RetSat as a widely shared component of mechanisms involved in insulin resistance and sensitivity and adds to the growing importance of the retinol pathway in diabetes, adipogenesis and insulin resistance. Top candidates obtained from our analysis have been confirmed in recent laboratory studies.

Contact:  Isaac_kohane@harvard.edu
Construct Validity of the Holistic Complementary and Alternative Medicines Questionnaire (HCAMQ)—An Investigation Using Modern Psychometric Approaches
Authors: Kersten Paula , White P. J. , Tennant A.
Published: October 2009

The scientific basis of efficacy studies of complementary medicine requires the availability of validated measures. The Holistic Complementary and Alternative Medicine Questionnaire (HCAMQ) is one such measure. This article aimed to examine its construct validity, using a modern psychometric approach. The HCAMQ was completed by 221 patients (mean age 66.8, SD 8.29, 58% females) with chronic stable pain predominantly from a single joint (hip or knee) of mechanical origin, waiting for a hip (40%) or knee (60%) joint replacement, on enrolment in a study investigating the effects of acupuncture and placebo controls. The HCAMQ contains a Holistic Health (HH) Subscale (five items) and a CAM subscale (six items). Validity of the subscales was tested using Cronbach alpha′s, factor analysis, Mokken scaling and Rasch analysis, which did not support the original two‐factor structure of the scale. A five‐item HH subscale and a four‐item CAM subscale (worded in a negative direction) fitted the Rasch model and were unidimensional (χ2 = 8.44, P = 0.39, PSI = 0.69 versus χ2 = 17.33, P = 0.03, PSI = 0.77). Two CAM items (worded in the positive direction) had significant misfit. In conclusion, we have shown that the original two‐factor structure of the HCAMQ could not be supported but that two valid shortened subscales can be used, one for HH Beliefs (four‐item HH), and the other for CAM Beliefs (four‐item CAM). It is recommended that consideration is given to rewording the two discarded positively worded CAM questions to enhance construct validity.
Intracoronary infusion of bone marrow‐derived mononuclear cells abrogates adverse left ventricular remodelling post‐acute myocardial infarction: insights from the reinfusion of enriched progenitor cells and infarct remodelling in acute myocardial infarction (REPAIR‐AMI) trial
Authors: Schächinger Volker , Assmus Birgit , Erbs Sandra , Elsässer Albrecht , Haberbosch Werner , Hambrecht Rainer , Yu Jiangtao , Corti Roberto , Mathey Detlef G. , Hamm Christian W. , Tonn Torsten , Dimmeler Stefanie , Zeiher Andreas M. ,   for the REPAIR‐AMI investigators
Published: September 2009

Aims

Depressed left ventricular ejection fraction (LVEF) despite successful reperfusion therapy is the single most powerful predictor of progressive LV enlargement after acute myocardial infarction (AMI) and independently determines adverse outcome in these patients.

Methods and results

We investigated the effect of intracoronary administration of bone marrow‐derived mononuclear cells (BMC) within 7 days after successful reperfusion therapy for AMI, on early (within 4 months) LV remodelling processes assessed by quantitative LV angiography. Overall, 95 patients received BMC and 92 patients received placebo. Remodelling was assessed as the changes in either LVEF and end‐systolic volume (ESV) or stroke volume and end‐diastolic volume (EDV) at 4 months, respectively. Baseline LVEF was inversely correlated with ESV expansion at 4 months in the placebo group, but not in the BMC group. Likewise, EDV expansion was significantly correlated with baseline LVEF in the placebo (r = −0.36, P < 0.001), but not in the BMC group (r = −0.17, P = 1.0). Analysing the interaction between convalescent LV contractile function and LV volumes revealed that the increase in LVEF or stroke volume did not occur at the expense of increases in ESV or EDV, respectively, in the BMC group.

Conclusion

Intracoronary administration of BMC eliminates the correlation between depressed LVEF after reperfusion therapy and LV expansion during follow‐up and, thereby, abrogates early LV remodelling after AMI.
Hawthorn Extract Randomized Blinded Chronic Heart Failure (HERB CHF) Trial
Authors: Zick Suzanna M. , Vautaw Bonnie Motyka , Gillespie Brenda , Aaronson Keith D.
Published: September 2009

Aims

Hawthorn's efficacy when added to contemporary evidence‐based heart failure therapy is unknown. We aimed to determine whether hawthorn increases submaximal exercise capacity when added to standard medical therapy.

Methods and results

We performed a randomized, double‐blind, placebo‐controlled trial in 120 ambulatory patients aged ≥18 years with New York Heart Association (NYHA) class II‐III chronic heart failure. All patients received conventional medical therapy, as tolerated, and were randomized to either hawthorn 450 mg twice daily or placebo for 6 months. The primary outcome was change in 6 min walk distance at 6 months. Secondary outcomes included quality of life (QOL) measures, peak oxygen consumption, and anaerobic threshold during maximal treadmill exercise testing, NYHA classification, left ventricular ejection fraction (LVEF), neurohormones, and measures of oxidative stress and inflammation. There were no significant differences between groups in the change in 6 min walk distance (P = 0.61), or on measures of QOL, functional capacity, neurohormones, oxidative stress, or inflammation. A modest difference in LVEF favoured hawthorn (P = 0.04). There were significantly more adverse events reported in the hawthorn group (P = 0.02), although most were non‐cardiac.

Conclusion

Hawthorn provides no symptomatic or functional benefit when given with standard medical therapy to patients with heart failure.

This trial is registered in ClinicalTrials.gov ID: NCT00343902.
Sharp global nonlinear stability for a fluid overlying a highly porous material
Authors: Hill Antony A. , Carr Magda
Published: October 2009

The stability of convection in a two-layer system in which a layer of fluid with a temperature-dependent viscosity overlies and saturates a highly porous material is studied. Owing to the difficulties associated with incorporating the nonlinear advection term in the Navier–Stokes equations into a stability analysis, previous literature on fluid/porous thermal convection has modelled the fluid using the linear Stokes equations. This paper derives global stability for the full nonlinear system, by utilizing a model proposed by Ladyzhenskaya. The nonlinear stability boundaries are shown to be sharp when compared with the linear instability thresholds.
Identification of genetic and phenotypic differences associated with prevalent and non-prevalent Salmonella Enteritidis phage types: analysis of variation in amino acid transport
Authors: Pan Zhensheng , Carter Ben , Núñez-García Javier , AbuOun Manal , Fookes María , Ivens Al , Woodward Martin J. , Anjum Muna F.
Published: September 2009

In this study, differences at the genetic level of 37 Salmonella Enteritidis strains from five phage types (PTs) were compared using comparative genomic hybridization (CGH) to assess differences between PTs. There were approximately 400 genes that differentiated prevalent (4, 6, 8 and 13a) and sporadic (11) PTs, of which 35 were unique to prevalent PTs, including six plasmid-borne genes, pefA, B, C, D, srgC and rck, and four chromosomal genes encoding putative amino acid transporters. Phenotype array studies also demonstrated that strains from prevalent PTs were less susceptible to urea stress and utilized l-histidine, l-glutamine, l-proline, l-aspartic acid, gly-asn and gly-gln more efficiently than PT11 strains. Complementation of a PT11 strain with the transporter genes from PT4 resulted in a significant increase in utilization of the amino acids and reduced susceptibility to urea stress. In epithelial cell association assays, PT11 strains were less invasive than other prevalent PTs. Most strains from prevalent PTs were better biofilm formers at 37 °C than at 28 °C, whilst the converse was true for PT11 strains. Collectively, the results indicate that genetic and corresponding phenotypic differences exist between strains of the prevalent PTs 4, 6, 8 and 13a and non-prevalent PT11 strains that are likely to provide a selective advantage for strains from the former PTs and could help them to enter the food chain and cause salmonellosis.
Conditioning of the membrane fatty acid profile of Escherichia coli during periodic temperature cycling
Authors: Ivancic Tina , Vodovnik Masa , Marinsek-Logar Romana , Stopar David
Published: September 2009

The membrane fatty acid composition of Escherichia coli becomes conditioned during periodic temperature cycling between 37 and 8 °C. After several cycles of temperature change, the bacteria become locked into a low-temperature physiology. Even after a prolonged incubation at high temperature the membrane fatty acid composition of conditioned cells was similar to that of cold-stressed cells.
Phylogenetic evidence for extensive horizontal gene transfer of type III secretion system genes among enterobacterial plant pathogens
Authors: Naum Marianna , Brown Eric W. , Mason-Gamer Roberta J.
Published: September 2009

This study uses sequences from four genes, which are involved in the formation of the type III secretion apparatus, to determine the role of horizontal gene transfer in the evolution of virulence genes for the enterobacterial plant pathogens. Sequences of Erwinia, Brenneria, Pectobacterium, Dickeya and Pantoea were compared (a) with one another, (b) with sequences of enterobacterial animal pathogens, and (c) with sequences of plant pathogenic γ and β proteobacteria, to evaluate probable paths of lateral exchange leading to the current distribution of virulence determinants among these micro-organisms. Phylogenies were reconstructed based on hrcC, hrcR, hrcJ and hrcV gene sequences using parsimony and maximum-likelihood algorithms. Virulence gene phylogenies were also compared with several housekeeping gene loci in order to evaluate patterns of lateral versus vertical acquisition. The resulting phylogenies suggest that multiple horizontal gene transfer events have occurred both within and among the enterobacterial plant pathogens and plant pathogenic γ and β proteobacteria. hrcJ sequences are the most similar, exhibiting anywhere from 2 to 50 % variation at the nucleotide level, with the highest degree of variation present between plant and animal pathogen sequences. hrcV sequences are conserved among plant and animal pathogens at the N terminus. The C-terminal domain is conserved only among the enterobacterial plant pathogens, as are the hrcC and hrcR sequences. Additionally, hrcJ and hrcV sequence phylogenies suggest that at least some type III secretion system virulence genes from enterobacterial plant pathogens are related more closely to those of the genus Pseudomonas, a conclusion neither supported nor refuted by hrcC or hrcR.
The cell wall galactomannan antigen from Malassezia furfur and Malassezia pachydermatis contains β-1,6-linked linear galactofuranosyl residues and its detection has diagnostic potential
Authors: Shibata Nobuyuki , Saitoh Tomomi , Tadokoro Yukari , Okawa Yoshio
Published: September 2009

Lipophilic yeasts of the genusMalasseziaare associated with several skin diseases, such as pityriasis versicolor,Malasseziafolliculitis, seborrhoeic dermatitis and atopic dermatitis, and are also increasingly associated with catheter-related fungaemia. The cell wall components of pathogenic micro-organisms behave as an antigen and/or ligand of the innate immune response. Live cells ofMalassezia furfurandMalassezia pachydermatisdid not react with an anti-α-1,2-mannoside antibody. However, they showed a strong hydrophobicity and reactivity with an anti-β-1,3-glucan antibody compared to those ofC. albicans. The cell wall polysaccharides ofM. furfurandM. pachydermatiswere isolated and their structures analysed by1H and13C NMR experiments. Both polysaccharides were shown to beβ-1,6-linked linear galactofuranosyl polymers with a small amount of mannan. The presence of galactomannan on cells ofMalasseziaspecies has not been described previously. The galactomannan did not react with an anti-Aspergillus fumigatusmonoclonal antibody which has specificity forβ-1,5-linked galactofuranosyl residues. An anti-M. furfurantibody strongly reacted with the galactomannans ofM. furfurandM. pachydermatis,but did not react with the galactomannans ofTrichophyton rubrum,A. fumigatusorFonsecaea pedrosoi.The characteristics of the anti-M. furfurantibody suggest that there is potential for diagnosis ofMalasseziainfections by antigen detection.
Oceanobacter-related bacteria are important for the degradation of petroleum aliphatic hydrocarbons in the tropical marine environment
Authors: Teramoto Maki , Suzuki Masahito , Okazaki Fumiyoshi , Hatmanti Ariani , Harayama Shigeaki
Published: September 2009

Petroleum-hydrocarbon-degrading bacteria were obtained after enrichment on crude oil (as a ‘chocolate mousse’) in a continuous supply of Indonesian seawater amended with nitrogen, phosphorus and iron nutrients. They were related to Alcanivorax and Marinobacter strains, which are ubiquitous petroleum-hydrocarbon-degrading bacteria in marine environments, and to Oceanobacter kriegii (96.4–96.5 % similarities in almost full-length 16S rRNA gene sequences). The Oceanobacter-related bacteria showed high n-alkane-degrading activity, comparable to that of Alcanivorax borkumensis strain SK2. On the other hand, Alcanivorax strains exhibited high activity for branched-alkane degradation and thus could be key bacteria for branched-alkane biodegradation in tropical seas. Oceanobacter-related bacteria became most dominant in microcosms that simulated a crude oil spill event with Indonesian seawater. The dominance was observed in microcosms that were unamended or amended with fertilizer, suggesting that the Oceanobacter-related strains could become dominant in the natural tropical marine environment after an accidental oil spill, and would continue to dominate in the environment after biostimulation. These results suggest that Oceanobacter-related bacteria could be major degraders of petroleum n-alkanes spilt in the tropical sea.
Cytotoxicity of Brucella smooth strains for macrophages is mediated by increased secretion of the type IV secretion system
Authors: Zhong Zhijun , Wang Yufei , Qiao Feng , Wang Zhoujia , Du Xinying , Xu Jie , Zhao Jin , Qu Qing , Dong Shicun , Sun Yansong , Huang Liuyu , Huang Kehe , Chen Zeliang
Published: September 2009

Some Brucella rough mutants cause cytotoxicity that resembles oncosis and necrosis in macrophages. This cytotoxicity requires the type IV secretion system (T4SS). In rough mutants, the cell-surface O antigen is shortened and the T4SS structure is thus exposed on the surface. Cytotoxicity effector proteins can therefore be more easily secreted. This enhanced secretion of effector proteins might cause the increased levels of cytotoxicity observed. However, whether this cytotoxicity is unique to the rough mutant and is mediated by overexpression of the T4SS has not been definitively determined. To test this, in the present study, a virB inactivation mutant (BMΔvirB) and an overexpression strain (BM-VIR) of a smooth Brucella melitensis strain (BM) were constructed and their cytotoxicity for macrophages and intracellular survival capability were analysed and compared. Cytotoxicity was detected in macrophages infected with higher concentrations of strains BM or BM-VIR, but not in those infected with BMΔvirB. The quorum sensing signal molecule N-dodecanoyl-dl-homoserine lactone (C12-HSL), a molecule that can inhibit expression of virB, inhibited the cytotoxicity of BM and BM-VIR, but not of BMΔvirB. These results indicated that overexpression of virB is responsible for Brucella cytotoxicity in macrophages. Transcription analysis showed that virB is regulated in a cell-density-dependent manner both in in vitro culture and during macrophage infection. When compared with BM, BM-VIR showed a reduced survival capacity in macrophages and mice, but both strains demonstrated similar resistance to in vitro stress conditions designed to simulate intracellular environments. Taken together, the cytotoxicity of Brucella for macrophages is probably mediated by increased secretion of effector proteins that results from overexpression of virB or an increase in the number of bacterial cells. The observation that both inactivation and overexpression of virB are detrimental for Brucella intracellular survival also indicated that the expression of virB is tightly regulated in a cell-density-dependent manner.
Nitric oxide mediates the fungal-elicitor-enhanced biosynthesis of antioxidant polyphenols in submerged cultures of Inonotus obliquus
Authors: Zheng Weifa , Miao Kangjie , Zhang Yanxia , Pan Shenyuan , Zhang Meimei , Jiang Hong
Published: September 2009

A fungal elicitor prepared from the cell debris of the plant-pathogenic ascomyceteAlternaria alternatainduces multiple responses byInonotus obliquuscells, including an increase in generation of nitric oxide (NO), activity of phenylalanine ammonia lyase (PAL) and accumulation of total mycelial phenolic compounds (TMP), but does not trigger production of oxylipins or jasmonic acid (JA). The role of NO in TMP production was investigated via the effects of the NO-specific scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPITO) and the nitric oxide synthase (NOS) inhibitor aminoguanidine (AG). TMP profiles were assayed using1H NMR spectroscopy combining multivariate pattern recognition strategies. Pretreatment ofI. obliquusmycelia with cPITO or AG suppressed not only elicitor-enhanced NO generation and PAL activity, but also the elicitor-induced increase in TMP production. This TMP reduction by either a NO scavenger or a NOS inhibitor was reversed by exogenous addition of either a NO donor, sodium nitroprusside, or JA separately. NMR-based metabonomic analysis of TMP profiles showed that the induced TMP were hispidin analogues including inoscavins, phelligridins, davallialactone and methyldavallialactone, which possess high antioxidant activities. Thus, NO mediates an elicitor-induced increase in production of antioxidant polyphenols inI. obliquusvia a signalling pathway independent of oxylipins or JA, a mechanism which differs from those in some higher plants.
Occurrence and characterization of peptaibols from Trichoderma citrinoviride, an endophytic fungus of cork oak, using electrospray ionization quadrupole time-of-flight mass spectrometry
Authors: Maddau Lucia , Cabras Annalisa , Franceschini Antonio , Linaldeddu Benedetto T. , Crobu Salvatore , Roggio Tonina , Pagnozzi Daniela
Published: September 2009

A cork oak endophytic strain of Trichoderma citrinoviride, previously selected for its antagonistic potential against various fungal pathogens involved in oak decline, was screened for the production of bioactive secondary metabolites. From liquid culture a mixture of polypeptide antibiotics (peptaibols) belonging to the paracelsin family was isolated and characterized. This peptide mixture was purified by column chromatography and preparative TLC on silica gel, and separated by analytical HPLC. It was analysed by MALDI-TOF MS and nano-ESI-QTOF MS. Tandem mass experiments were performed to determine the amino acid sequences based on the fragmentation pattern of selected parent ions. The mixture comprised 20-residue peptides with C-terminal phenylalaninol and N-terminal acetylation. Twenty-eight amino acid sequences were identified, and amino acid exchanges were located in positions 6, 9, 12 and 17. Among them, seven sequences are new as compared to those reported in the database specifically for peptaibols and in the literature. In addition, we obtained experimental evidence suggesting the existence of non-covalent dimeric forms (homo- and hetero-) of the various peptaibol species. The peptide mixture showed strong antifungal activity toward seven important forest tree pathogens, and it was highly toxic in an Artemia salina (brine shrimp) bioassay. These results emphasize the cryptic role of endophytic fungi as a source of novel bioactive natural products and biocontrol agents.
The protease CspB is essential for initiation of cortex hydrolysis and dipicolinic acid (DPA) release during germination of spores of Clostridium perfringens type A food poisoning isolates
Authors: Paredes-Sabja Daniel , Setlow Peter , Sarker Mahfuzur R.
Published: September 2009

The genome of the Clostridium perfringens food poisoning isolate SM101 encodes a subtilisin-like protease, CspB, upstream of the sleC gene encoding the enzyme essential for degradation of the peptidoglycan cortex during spore germination. SleC is an inactive pro-SleC in dormant spores that is converted to active SleC during spore germination and Csp proteases convert pro-SleC to the active enzyme in vitro. In this work, the germination and viability of spores of a cspB deletion mutant of strain SM101, as well as cspB expression, were studied. The cspB gene was expressed only during sporulation, and only in the mother cell compartment. cspB spores were unable to germinate significantly with either a rich nutrient medium, KCl, or a 1 : 1 chelate of Ca2+ and dipicolinic acid (DPA); the viability of these spores was ∼104-fold lower than that of wild-type spores, although cspB and wild-type spores had similar viability on plates containing lysozyme, and cspB spores could not process inactive pro-SleC into active SleC during spore germination. Germination of cspB spores was blocked prior to DPA release and cortex hydrolysis, and germination and viability defects in these spores were complemented by an ectopic cspB. These results indicate that Csp proteases are essential to generate active SleC and allow cortex hydrolysis early in C. perfringens spore germination. However, Csp proteases likely play another role in spore germination, since cspB spores did not release DPA upon exposure to germinants, while sleC spores have been shown previously to release DPA, albeit slowly, upon exposure to germinants.