bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chloroplast His-to-Asp signal transduction: a potential mechanism for plastid gene regulation in Heterosigma akashiwo (Raphidophyceae)
Authors: Duplessis Melinda R , Karol Kenneth G , Adman Elinor T , Choi Lauren YS , Jacobs Michael A , Cattolico Rose Ann 
Published: May 2007

Abstract

Background
Maintenance of homeostasis requires that an organism perceive selected physical and chemical signals within an informationally dense environment. Functionally, an organism uses a variety of signal transduction arrays to amplify and convert these perceived signals into appropriate gene transcriptional responses. These changes in gene expression serve to modify selective metabolic processes and thus optimize reproductive success. Here we analyze a chloroplast-encoded His-to-Asp signal transduction circuit in the stramenopile Heterosigma akashiwo (Hada) Hada ex Y. Hara et Chihara [syn. H. carterae (Hulburt) F.J.R. Taylor]. The presence, structure and putative function of this protein pair are discussed in the context of their evolutionary homologues.

Results
Bioinformatic analysis of the Heterosigma akashiwo chloroplast genome sequence revealed the presence of a single two-component His-to-Asp (designated Tsg1/Trg1) pair in this stramenopile (golden-brown alga). These data represent the first documentation of a His-to-Asp array in stramenopiles and counter previous reports suggesting that such regulatory proteins are lacking in this taxonomic cluster. Comparison of the 43 kDa H. akashiwo Tsg1 with bacterial sensor kinases showed that the algal protein exhibits a moderately maintained PAS motif in the sensor kinase domain as well as highly conserved H, N, G1 and F motifs within the histidine kinase ATP binding site. Molecular modelling of the 27 kDa H. akashiwo Trg1 regulator protein was consistent with a winged helix-turn-helix identity – a class of proteins that is known to impact gene expression at the level of transcription. The occurrence of Trg1 protein in actively growing H. akashiwo cells was verified by Western analysis. The presence of a PhoB-like RNA polymerase loop in Trg1 and its homologues in the red-algal lineage support the hypothesis that Trg1 and its homologues interact with a sigma 70 (σ70) subunit (encoded by rpoD) of a eubacterial type polymerase. Sequence analysis of H. akashiwo rpoD showed this nuclear-encoded gene has a well-defined 4.2 domain, a region that augments RNA polymerase interaction with transcriptional regulatory proteins and also serves in -35 promoter recognition. The presence/loss of the His-to-Asp pairs in primary and secondary chloroplast lineages is assessed.

Conclusion
His-to-Asp signal transduction components are found in most rhodophytic chloroplasts, as well as in their putative cyanobacterial progenitors. The evolutionary conservation of these proteins argues that they are important for the maintenance of chloroplast homeostasis. Our data suggest that chloroplast gene transcription may be impacted by the interaction of the His-to-Asp regulator protein (which is less frequently lost than the sensor protein) with the RNA polymerase σ70 subunit.
Practice development plans to improve the primary care management of acute asthma: randomised controlled trial
Authors: Foster Juliet M , Hoskins Gaylor , Smith Barbara , Lee Amanda J , Price David , Pinnock Hilary 
Published: April 2007

Abstract

Background
Our professional development plan aimed to improve the primary care management of acute asthma, which is known to be suboptimal.

Methods
We invited 59 general practices in Grampian, Scotland to participate. Consenting practices were randomised to early and delayed intervention groups. Practices undertook audits of their management of all acute attacks (excluding children under 5 years) occurring in the 3 months preceding baseline, 6-months and 12-months study time-points. The educational programme [including feedback of audit results, attendance at a multidisciplinary interactive workshop, and formulation of development plan by practice teams] was delivered to the early group at baseline and to the delayed group at 6 months. Primary outcome measure was recording of peak flow compared to best/predicted at 6 months. Analyses are presented both with, and without adjustment for clustering.

Results
23 consenting practices were randomised: 11 to early intervention. Baseline practice demography was similar. Six early intervention practices withdraw before completing the baseline audit. There was no significant improvement in our primary outcome measure (the proportion with peak flow compared to best/predicted) at either the 6 or 12 month time points after adjustment for baseline and practice effects. However, the between group difference in the adjusted combined assessment score, whilst non-significant at 6 months (Early: 2.48 (SE 0.43) vs. Delayed 2.26 (SE 0.33) p = 0.69) reached significance at 12 m (Early:3.60 (SE 0.35) vs. Delayed 2.30 (SE 0.28) p = 0.02).

Conclusion
We demonstrated no significant benefit at the a priori 6-month assessment point, though improvement in the objective assessment of attacks was shown after 12 months. Our practice development programme, incorporating audit, feedback and a workshop, successfully engaged the healthcare team of participating practices, though future randomised trials of educational interventions need to recognise that effecting change in primary care practices takes time. Monitoring of the assessment of acute attacks proved to be a feasible and responsive indicator of quality care.
Quality of life assessment in women with breast cancer: benefits, acceptability and utilization
Authors: Perry Sheila , Kowalski Theresa L , Chang Chih-Hung 
Published: May 2007

Abstract
In 2006, breast cancer was the third leading cause of death in American women; however, more women survive breast cancer than any other type of cancer. As the disease progresses, it is important to know how one's health-related quality of life (QOL) is affected for those who receive treatment, those who survive, and those who remain disease-free. The purpose of this study was to summarize the benefits, challenges, and barriers of QOL measurement for female breast cancer patients. A PubMed literature search was conducted using the terms "quality of life" and "breast cancer." The search was then refined with terms related to QOL assessment instruments. The research team reviewed over 100 of the 2,090 articles identified.
From the results, a detailed outline of QOL instruments is presented, and the effectiveness of QOL instruments is discussed. In the current literature review, both generic and breast cancer specific QOL instruments, examining computerized and paper-and-pencil versions, are explained as well as the advantages, acceptability, and problems of these assessments. Potential barriers to implementation are also discussed. The implementation of QOL assessment tools in breast cancer clinical practice is discussed, with evidence detailing how such tools would benefit patients.
Desert ants do not acquire and use a three-dimensional global vector
Authors: Grah Gunnar , Wehner Rüdiger , Ronacher Bernhard 
Published: May 2007

Abstract

Background

Desert ants (Cataglyphis fortis) are central place foragers that navigate by means of path integration. This mechanism remains accurate even on three-dimensional itineraries. In this study, we tested three hypotheses concerning the underlying principles of Cataglyphis' orientation in 3-D: (1) Do the ants employ a strictly two-dimensional representation of their itineraries, (2) do they link additional information about ascents and descents to their 2-D home vector, or (3) do they use true 3-D vector navigation?

Results

We trained ants to walk routes within channels that included ascents and descents. In choice tests, ants walked on ramps more frequently and at greater lengths if their preceding journey also included vertical components. However, the sequence of ascents and descents, as well as their distance from nest and feeder, were not retraced. Importantly, the animals did not compensate for an enforced vertical deviation from the home vector.

Conclusion

We conclude that Cataglyphis fortis essentially represents its environment in a simplified, two-dimensional fashion, with information about vertical path segments being learnt, but independently from their congruence with the actual three-dimensional configuration of the environment. Our findings render the existence of a path integration mechanism that is functional in all three dimensions highly unlikely.
Effectiveness of polymyxin B-immobilized fiber column in sepsis: a systematic review
Authors: Cruz Dinna N , Perazella Mark A , Bellomo Rinaldo , de Cal Massimo , Polanco Natalia , Corradi Valentina , Lentini Paolo , Nalesso Federico , Ueno Takuya , Ranieri V Marco , Ronco Claudio 
Published: April 2007

Abstract
Introduction
Severe sepsis and septic shock are common problems in the intensive care unit and carry a high mortality. Endotoxin, one of the principal components on the outer membrane of gram-negative bacteria, is considered important to their pathogenesis. Polymyxin B bound and immobilized to polystyrene fibers (PMX-F) is a medical device that aims to remove circulating endotoxin by adsorption, theoretically preventing the progression of the biological cascade of sepsis. We performed a systematic review to describe the effect in septic patients of direct hemoperfusion with PMX-F on outcomes of blood pressure, use of vasoactive drugs, oxygenation, and mortality reported in published studies.

Methods
We searched PubMed, the Cochrane Collaboration Database, and bibliographies of retrieved articles and consulted with experts to identify relevant studies. Prospective and retrospective observational studies, pre- and post-intervention design, and randomized controlled trials were included. Three authors reviewed all citations. We identified a total of 28 publications – 9 randomized controlled trials, 7 non-randomized parallel studies, and 12 pre-post design studies – that reported at least one of the specified outcome measures (pooled sample size, 1,425 patients: 978 PMX-F and 447 conventional medical therapy).

Results
Overall, mean arterial pressure (MAP) increased by 19 mm Hg (95% confidence interval [CI], 15 to 22 mm Hg; p < 0.001), representing a 26% mean increase in MAP (range, 14% to 42%), whereas dopamine/dobutamine dose decreased by 1.8 μg/kg per minute (95% CI, 0.4 to 3.3 μg/kg per minute; p = 0.01) after PMX-F. There was significant intertrial heterogeneity for these outcomes (p < 0.001), which became non-significant when analysis was stratified for baseline MAP. The mean arterial partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio increased by 32 units (95% CI, 23 to 41 units; p < 0.001). PMX-F therapy was associated with significantly lower mortality risk (risk ratio, 0.53; 95% CI, 0.43 to 0.65). The trials assessed had suboptimal method quality.

Conclusion
Based on this critical review of the published literature, direct hemoperfusion with PMX-F appears to have favorable effects on MAP, dopamine use, PaO2/FiO2 ratio, and mortality. However, publication bias and lack of blinding need to be considered. These findings support the need for further rigorous study of this therapy.
Monocyte subpopulations and their differentiation patterns during infection
Authors: Strauss-Ayali Dalit , Conrad Sean M , Mosser David M 
Published: May 2007

AbstractThe term “monocyte” implies a single, homogenous population of cells with uniform physiology. Recent evidence from a number of laboratories indicates that it is likely that blood monocytes may consist of several subpopulations of cells, which differ in size, nuclear morphology, granularity, and functionality. The aim of this review is to give a summary of the new findings in the emerging field of monocyte heterogeneity. We provide a short description of the differentiation patterns of blood monocyte subpopulations, with an emphasis on how these subpopulations can be influenced by infection. We provide a comparison among the main monocyte subpopulations in humans, mice, and rats and illustrate some of the common features of these cells and some of the important interspecies distinctions. We will also discuss the bone marrow precursors of these cells and the differentiation patterns of these subsets in different tissues in response to infection. Most of the data about monocyte trafficking during infection are necessarily derived from murine models, and comparisons between mouse and man must be made with caution. However, these models may provide interesting springboards to permit us to speculate about the topic of monocyte heterogeneity in humans.
TGF-β1 modulates Foxp3 expression and regulatory activity in distinct CD4+ T cell subsets
Authors: Pyzik M , Piccirillo C A 
Published: May 2007

AbstractAlthough forkhead box p3 (Foxp3) expression is restricted to naturally occurring CD4+ regulatory T cells (TREG), little is known about the various signals that regulate it in T cells. As TGF-β has been reported to modulate Foxp3 expression in T cells, we investigated its effects on the induction or maintenance of regulatory functions in different CD4+ T cell subsets. TGF-β1 priming was able to promote differentiation of TREG cells from nonregulatory CD4+CD25– T cells in a concentration-dependent manner through Foxp3 induction. As CD4+CD25– T cells remain a highly heterogeneous population with variable degrees of antigen experience, we then examined the effect of TGF-β1 on naive CD4+CD25–CD45RBHIGH T cells. Freshly isolated or TGF-β1-treated CD4+CD25–CD45RBHIGH T cells never displayed any regulatory functions or significant Foxp3 expression following TCR activation. In stark contrast, freshly isolated CD4+CD25–CD45RBLOW cells, albeit expressing low levels of Foxp3 mRNA and protein, were unable to suppress CD4+ effector T cell proliferation but acquired regulatory activity and de novo Foxp3 expression following TGF-β1 exposure. Furthermore, suppression was IL-10-dependent, as anti-IL-10 receptor antibody treatment abrogated this suppression completely, consistent with the ability of TGF-β1-treated CD4+CD25–CD45RBLOW to synthesize IL-10 upon restimulation in vitro. Last, we show that TGF-β1 treatment or blockade did not lead to enhanced expansion or function of naturally occurring CD4+CD25+ TREG cells, although it maintained Foxp3 mRNA and protein expression. Altogether, TGF-β1 promotes the induction of IL-10-secreting CD4+ TREG cells from CD4+CD25–CD45RBLOW precursors through de novo Foxp3 production and maintains natural TREG cell peripheral homeostasis by sustaining Foxp3 expression.
Target groups for the prevention of late-life anxiety
Authors: Smit Filip , Comijs Hannie , Schoevers Robert , Cuijpers Pim , Deeg Dorly , Beekman Aartjan 
Published: April 2007

BackgroundAnxiety disorders in older people are highly prevalent, yet there is little evidence to guide targeted prevention strategies.AimsTo identify subgroups at increased risk of developing anxiety in later life.MethodAnxiety was measured with the Hospital Anxiety and Depression anxiety sub-scale in 1931 people aged 55–85 years followed over 3 years. Risk factors were identified that had a high combined attributable fraction, indicative of substantial health gains when the adverse effect of the risk factors can be contained.ResultsFactors significantly associated with increased risk of developing anxiety included sub-threshold anxiety depression, two or more chronic illnesses, poor sense of mastery, poor self-rated health and low educational level.ConclusionsThe identified risk groups are small, thus providing prevention with a narrow focus, and health gains are likely to be more substantial than in groups not exposed to these risk factors. Nevertheless, more research is needed to produce evidence on target groups where prevention has optimal impacts.
Randomized Trial of Exercise Therapy in Women Treated for Breast Cancer
Authors: Daley Amanda J. , Crank Helen , Saxton John M. , Mutrie Nanette , Coleman Robert , Roalfe Andrea 
Published: April 2007

PurposeTo examine the effects of aerobic exercise therapy on quality of life (QoL) and associated outcomes in women treated for breast cancer. Evidence suggests that exercise may be beneficial, but no trial has included an exercise-placebo and a usual-care group to control for the attention effects that might be associated with aerobic exercise interventions in cancer patients.Patients and MethodsA total of 108 women who had been treated for breast cancer 12 to 36 months previously were randomly assigned to supervised aerobic exercise therapy (n = 34), exercise-placebo (body conditioning; n = 36), or usual care (n = 38). Exercise therapy and exercise-placebo sessions took place three times per week for 8 weeks. Outcomes included QoL, depression, exercise behavior, aerobic fitness; outcomes were assessed at baseline and at the 8- and 24-week follow-up.ResultsAnalyses of covariance revealed a significant mean difference of 9.8 units in Functional Assessment of Cancer Therapy–General (primary outcome) favoring aerobic exercise therapy at 8 weeks, relative to usual care. Significant differences that favored aerobic exercise therapy relative to usual care were recorded for Functional Assessment of Cancer Therapy–Breast, social/family well-being, functional well-being, and breast cancer subscale scores at 8-week follow-up. Psychological health outcomes improved modestly for both intervention groups; these improvements were sustained for several end points.ConclusionExercise therapy had large, clinically meaningful, short-term beneficial effects on QoL in women treated for breast cancer; this finding cannot be attributable to attention, given that the exercise-placebo group did not report similar effects relative to usual care.
Analysis and Design of Profiled Dies for the Polymer Wire Die-Drawing Process
Authors: Mohanraj J , Bonner M. J. , Barton D. C. , Ward I. M. 
Published: April 2007

In the standard polymer die-drawing process, using conventional conical dies, the strain and strain rate are maximum at the die exit where the stress state in the material, now oriented, is predominantly tensile in nature. This leads to fracture of the material at the die exit at high drawing speeds. In this paper, the plastic flow of the polymer in profiled dies, where the strain and strain rate are controlled along the die-length, is analysed theoretically and it is shown that the design of profiled dies can be chosen to reduce the strain rate at the die exit. A coupled thermo-mechanical finite-element model has been developed to study the detailed temperature, strain and strain rate distributions in conical and profiled die-designs and their effect on important processing parameters such as draw load and speed. The performance of conical and profile die designs has also been compared experimentally under identical drawing conditions for the specific case of die drawing of polyoxymethylene wire. Both the analytical and experimental results demonstrate the ability of the profile die designs to significantly increase the processing speed while retaining the high degree of orientation and enhanced properties of the die-drawn product.
Design of a High-Altitude Long-Endurance Solar-Powered Unmanned Air Vehicle for Multi-Payload and Operations
Authors: Romeo G , Frulla G , Cestino E 
Published: April 2007

Several researches are being carried out at the Politecnico di Torino with the aim of designing a high altitude very-long endurance/unmanned air vehicle (HAVE/UAV). Being able to fly in the stratosphere (15-20 km) and with an endurance of about 4 months offers an advantage and possibility that is presently not available with conventional aircraft or satellites. A computer program has been developed to design the platform. The change in solar radiation over a period of a year, the altitude, masses, and efficiencies of the solar and fuel cells, as well as the aerodynamic, structural, flight mechanics, and aeroelastic performances have all been taken into account. Extensive use has been made of high modulus graphite/epoxy when designing the structure in order to minimize the airframe weight, but also to guarantee the required stiffness and aeroelastic performance. A blended wing body (BWB) configuration has been selected for solar HAVE aircraft multi payload and operation (SHAMPO) with eight brushless electric motors, as the result of a preliminary design. The BWB solution has been designed according to the conventional procedures and airworthiness regulations. It seems to be the best compromise between performance, available surfaces for solar cells and volume for multi-payload purposes, compared to conventional design. Several profiles and wing plans have been analysed and optimized to achieve the best efficiency using the Xfoil and Vsaero computational fluid dynamics (CFD) software. A finiteelement method and a classical theoretical analysis was carried out using the Msc/Patran/Nastran code to predict the static and aeroelastic behaviour of the SHAMPO. Aeroelastic analysis has been performed starting with a classical linear flutter analysis and considering an undeformed equilibrium condition. Classical linear flutter speed show as the airworthiness requirements has been achieved in the case of SHAMPO configuration. A preliminary non-linear aeroelastic model is introduced in the design process in order to deal with specific phenomena correlated with high static structural deflections occurring during standard flight conditions. Important flutter speed reduction (i.e. up to 42 per cent in special cases) are possible including such kind of phenomena.
Effects of Telemetry Transmitter Placement on Egg Retention in Naturally Spawning, Captively Reared Steelhead
Authors: Berejikian Barry A. , Brown Richard S. , Tatara Christopher P. , Cooke Steven J. 
Published: May 2007

Abstract
Maturing female anadromous salmonids receiving intraperitoneally implanted telemetry transmitters (tags) may experience difficulty depositing eggs during natural spawning. We allocated maturing adult female steelhead Oncorhynchus mykiss to three treatment groups: (1) fish whose tags were surgically implanted in the body cavity (internal), (2) fish whose tags were implanted between the skin and muscle tissue (subdermal), and (3) nontagged fish. The steelhead were then allowed to spawn in an experimental channel. Internally tagged females retained significantly more eggs than did the subdermally tagged and nontagged control groups; subdermally tagged and nontagged control fish did not differ significantly. Females in the internally tagged, subdermally tagged, and nontagged groups retained an average of 49, 11, and 2% of their eggs, respectively. The onset of sexual activity did not differ significantly among treatments. Postspawning mortality was 70% for internally and subdermally tagged females and 0% for nontagged females. Each research or monitoring program should weigh the costs associated with transmitter use (where they are known) against the value of information obtained and should carefully evaluate assumptions about transmitter effects. For these reasons, the use of electromyogram electrodes and other telemetry transmitters for monitoring imperiled fish populations should be employed with caution. We suggest that subdermal implantation techniques be considered in future studies during the reproductive period to reduce egg retention caused by internally implanted transmitters.