bluuebunny/crossref_metadata_2025_split huggingface dataset:
TH‐D‐217A‐01: MR Safety Update, 2012: Where Are We, and Where Are We Going?
Authors: Kanal E 
Published: June 2012

It has now been almost 3 decades since the introduction of MRI as a vital component of our clinical diagnostic armamentarium. During that time, we have learned much about the potential safety concerns relating to the static and time varying electromagnetic fields used in the MR imaging process, as well as several non‐magnetic field safety issues unique to this modality. Industry application of some of this knowledge has enabled the relatively recent FDA‐approval and clinical introduction of new devices heretofore unavailable that are designed specifically to be conditionally safe in the clinical MR imaging environment. An example of such a device is a cardiac pacemaker system (i.e., pulse generator and accompanying leads) that was designed from the ground up with MR safety as an integral design objective. Until now, patients were referred to undergo MR imaging because of an identified or suspected disease process, such as neurological or musculoskeletal pathology. This was true for almost all patients except for those with significant heart disease. For them, until recently, those whose heart disease was of such a nature that they required the implantation of a cardiac pacemakers were essentially excluded from MRI access, or were permitted careful access on a case by case basis only after intricate procedures and monitoring personnel and capabilities were established or their particular MR imaging procedure. With the advent of MR conditional cardiac pacemaker systems, we have now just begun to embark on an era where people will not be imaged despite their having a cardiac pacemaker — but specifically because of it, as we now can finally include cardiac disease as one of the many pathologic entities for which MR imaging's impressive diagnostic potential can finally be clinically truly applied. This presentation will review the MR safety issues in general and present some recent clinical advances in this area in the form of new tools, new capabilities, and newly published guidelines relating to MR safety. Consultant for Guerbet, Medtronic, Speakers Bureau for Bracco Diagnostics.Learning Objectives:1. Define the major and minor categories of potential safety concerns in the magnetic resonance imaging environment2. Become aware of the recent advances in, and FDA approval of, cardiac pacing systems and their safe intra‐MRI utilization3. Review some of the modifications in the recently produced “American College of Radiology Guidance Document for Safe MR Practices:2012” and compare it to the prior 2007 version of this document.
The distribution of dissolved aluminum in Atlantic salmon (Salmo salar) rivers of Atlantic Canada and its potential effect on aquatic populations
Authors: Dennis Ian F. , Clair Thomas A. 
Published: June 2012

Studies from the 1980s concluded that aluminum (Al) was not a significant contributor to Atlantic salmon ( Salmo salar ) toxicity in Nova Scotia, located on Canada’s Atlantic coast, because of the presence of dissolved organic matter that rendered ionic Al (Ali) biologically inaccessible. Since this earlier work, new interpretations of Alieffects, as well as improved techniques for its measurement, have been developed. However, no new data interpretation has been done to see if the conclusions reached in earlier work for Atlantic Canada were still valid. We sampled 97 salmon rivers from the provinces of New Brunswick (NB), Nova Scotia (NS), and the island of Newfoundland (NF) to determine total and Aliconcentrations to see if results exceeded newer toxicity standards established by the European Inland Fisheries Advisory Commission. We found that southwestern NS, the region with the greatest loss of salmon populations, has seven rivers where autumn Alivalues exceed values identified as toxic to aquatic life. A further three rivers exceed guidelines in NF. Our work shows that the sources of toxicity for salmon and other aquatic species in acidified environments are more complex than previously thought.
Elevated mercury levels in biota along an agricultural land use gradient in the Oldman River basin, Alberta
Authors: Brinkmann Lars , Rasmussen Joseph B. 
Published: June 2012

This study examines relationships between anthropogenic influence and mercury concentrations in biota along an elevational river gradient with intensifying agricultural and urban land use in the Oldman River basin, Alberta, Canada. We use nitrogen stable isotope signatures (δ15N) indicative of anthropogenic sources of N to indicate the extent of land use influence on the river ecosystem. δ15N values in biota increased by 4.2‰ along the river gradient, consistent with increasing nitrogen sources from sewage and manure. Mercury concentrations in longnose dace ( Rhinichthys cataractae ), suckers ( Catostomus catostomus , Catostomus commersonii ), and net-spinning caddisfly larvae, the most abundant macroinvertebrates, all increased downstream; dace ranged from 0.023 ppm total mercury below the Oldman reservoir to 0.10 ppm total mercury downstream of Lethbridge. Dace consumed mostly insect larvae, and no increase in trophic position (as estimated by δ15N) was observed along the gradient. Fish directly exposed to agricultural and urban effluents had significantly lower mercury levels, or showed no difference, relative to reference sites, which suggests that these effluents play no significant role in elevating mercury levels in river food webs.
Autonomic mediation of the interdependence between variability signals of heart rate and blood pressure in the lizard Gallotia galloti
Authors: De Vera Luis , Rial Rubén V. , Pereda Ernesto , González Julián J. 
Published: June 2012

Autonomic nervous system (ANS) involvement in the mediation of the synchronization between beat-to-beat RR interval variability (RRIV) and systolic blood pressure variability (SBPV) signals of the lizard Gallotia galloti (Oudart, 1839) was investigated through linear and nonlinear time series analysis methods in a pharmacological blockade context. The ANS blockers used were atropine, prazosin, and propranolol. The interdependence between the signals was quantified by means of the magnitude-squared coherence (MSC), which measures amplitude and phase linear synchronization; the phase lag index (PLI), which evaluates the phase synchronization; and the index L, which quantifies the generalized linear and nonlinear synchronization. Atropine decreased the PLI in the low-frequency (LF: 0.01–0.05 Hz) range; prazosin decreased the MSC in the medium-frequency (MF: 0.06–0.15 Hz) range; and propranolol did not alter any of the interdependence measures. It is suggested that (i) the cholinoceptor activity mediates the phase cardiovascular synchronization in the LF range; (ii) the α1-adrenoceptor activity mediates the amplitude and phase linear cardiovascular synchronization in the MF range; and (iii) the β-adrenoceptor activity plays no role in mediating any dynamics of cardiovascular synchronization in the studied frequency range. When comparing these results with those in mammals, a lesser overall autonomic involvement in the mediation of the studied cardiovascular interdependences is seen in reptiles.
Assessment of Echocardiography and Biomarkers for the Extended Prediction of Cardiotoxicity in Patients Treated With Anthracyclines, Taxanes, and Trastuzumab
Authors: Sawaya Heloisa , Sebag Igal A. , Plana Juan Carlos , Januzzi James L. , Ky Bonnie , Tan Timothy C. , Cohen Victor , Banchs Jose , Carver Joseph R. , Wiegers Susan E. , Martin Randolph P. , Picard Michael H. , Gerszten Robert E. , Halpern Elkan F. , Passeri Jonathan , Kuter Irene , Scherrer-Crosbie Marielle 
Published: June 2012

Background—
Because cancer patients survive longer, the impact of cardiotoxicity associated with the use of cancer treatments escalates. The present study investigates whether early alterations of myocardial strain and blood biomarkers predict incident cardiotoxicity in patients with breast cancer during treatment with anthracyclines, taxanes, and trastuzumab.

Methods and Results—

Eighty-one women with newly diagnosed human epidermal growth factor receptor 2–positive breast cancer, treated with anthracyclines followed by taxanes and trastuzumab were enrolled to be evaluated every 3 months during their cancer therapy (total of 15 months) using echocardiograms and blood samples. Left ventricular ejection fraction, peak systolic longitudinal, radial, and circumferential myocardial strain were calculated. Ultrasensitive troponin I, N-terminal pro–B-type natriuretic peptide, and the interleukin family member (ST2) were also measured. Left ventricular ejection fraction decreased (64 ± 5% to 59 ± 6%;
P
<0.0001) over 15 months. Twenty-six patients (32%, [22%–43%]) developed cardiotoxicity as defined by the Cardiac Review and Evaluation Committee Reviewing Trastuzumab; of these patients, 5 (6%, [2%–14%]) had symptoms of heart failure. Peak systolic longitudinal myocardial strain and ultrasensitive troponin I measured at the completion of anthracyclines treatment predicted the subsequent development of cardiotoxicity; no significant associations were observed for left ventricular ejection fraction, N-terminal pro–B-type natriuretic peptide, and ST2. Longitudinal strain was <19% in all patients who later developed heart failure.

Conclusions—
In patients with breast cancer treated with anthracyclines, taxanes, and trastuzumab, systolic longitudinal myocardial strain and ultrasensitive troponin I measured at the completion of anthracyclines therapy are useful in the prediction of subsequent cardiotoxicity and may help guide treatment to avoid cardiac side-effects.
Effects of self-promoted curing behaviors on properties of phthalonitrile/epoxy copolymer
Authors: Guo Heng , Zou Yanke , Chen Zhiran , Zhang Jiandong , Zhan Yingqing , Yang Jian , Liu Xiaobo 
Published: June 2012

Thermosetting blends of 4-aminophenoxyphthalonitrile (APN)/epoxy resin (ER) were investigated by differential scanning calorimetry (DSC), dynamic rheological analysis and thermogravimetric analysis (TGA). The self-promoted curing behaviors and processing properties of the APN/ER blends and prepolymers were studied by DSC and rheological analysis under dynamic and isothermal conditions. The APN/ER blends and prepolymers exhibited two-step polymerization reactions in the absence of any other curing additives. The APN/ER blends and prepolymers had large processing windows with low melt viscosity, and the size of the processing windows was dependent on the APN monomer concentration. The thermal behaviors of the APN/ER copolymers were studied by TGA. These cured copolymers exhibited decomposition temperatures over 367 oC in either flowing nitrogen or air, and high char yield at 800 oC of 68% under nitrogen atmosphere. Consequently, these studies revealed that the APN/ER system exhibits attractive self-promoted curing reaction, desirable processing feature, excellent thermal and thermal-oxidative stabilities, and high char yields. The APN/ER copolymer will be a good candidate as a matrix for high-performance polymeric materials.
A systematic comparison of genome-scale clustering algorithms
Authors: Jay Jeremy J , Eblen John D , Zhang Yun , Benson Mikael , Perkins Andy D , Saxton Arnold M , Voy Brynn H , Chesler Elissa J , Langston Michael A 
Published: June 2012

Abstract

Background
A wealth of clustering algorithms has been applied to gene co-expression experiments. These algorithms cover a broad range of approaches, from conventional techniques such as k-means and hierarchical clustering, to graphical approaches such as k-clique communities, weighted gene co-expression networks (WGCNA) and paraclique. Comparison of these methods to evaluate their relative effectiveness provides guidance to algorithm selection, development and implementation. Most prior work on comparative clustering evaluation has focused on parametric methods. Graph theoretical methods are recent additions to the tool set for the global analysis and decomposition of microarray co-expression matrices that have not generally been included in earlier methodological comparisons. In the present study, a variety of parametric and graph theoretical clustering algorithms are compared using well-characterized transcriptomic data at a genome scale from Saccharomyces cerevisiae.

Methods
For each clustering method under study, a variety of parameters were tested. Jaccard similarity was used to measure each cluster's agreement with every GO and KEGG annotation set, and the highest Jaccard score was assigned to the cluster. Clusters were grouped into small, medium, and large bins, and the Jaccard score of the top five scoring clusters in each bin were averaged and reported as the best average top 5 (BAT5) score for the particular method.

Results
Clusters produced by each method were evaluated based upon the positive match to known pathways. This produces a readily interpretable ranking of the relative effectiveness of clustering on the genes. Methods were also tested to determine whether they were able to identify clusters consistent with those identified by other clustering methods.

Conclusions
Validation of clusters against known gene classifications demonstrate that for this data, graph-based techniques outperform conventional clustering approaches, suggesting that further development and application of combinatorial strategies is warranted.
On the origin of Mycobacterium ulcerans, the causative agent of Buruli ulcer
Authors: Doig Kenneth D , Holt Kathryn E , Fyfe Janet AM , Lavender Caroline J , Eddyani Miriam , Portaels Françoise , Yeboah-Manu Dorothy , Pluschke Gerd , Seemann Torsten , Stinear Timothy P 
Published: June 2012

Abstract

Background

Mycobacterium ulcerans is an unusual bacterial pathogen with elusive origins. While closely related to the aquatic dwelling M. marinum, M. ulcerans has evolved the ability to produce the immunosuppressive polyketide toxin mycolactone and cause the neglected tropical disease Buruli ulcer. Other mycolactone-producing mycobacteria (MPM) have been identified in fish and frogs and given distinct species designations (M. pseudoshottsii, M. shinshuense, M. liflandii and M. marinum), however the evolution of M. ulcerans and its relationship to other MPM has not been defined. Here we report the comparative analysis of whole genome sequences from 30 MPM and five M. marinum.

Results
A high-resolution phylogeny based on genome-wide single nucleotide polymorphisms (SNPs) showed that M. ulcerans and all other MPM represent a single clonal group that evolved from a common M. marinum progenitor. The emergence of the MPM was driven by the acquisition of the pMUM plasmid encoding genes for the biosynthesis of mycolactones. This change was accompanied by the loss of at least 185 genes, with a significant overrepresentation of genes associated with cell wall functions. Cell wall associated genes also showed evidence of substantial adaptive selection, suggesting cell wall remodeling has been critical for the survival of MPM. Fine-grain analysis of the MPM complex revealed at least three distinct lineages, one of which comprised a highly clonal group, responsible for Buruli ulcer in Africa and Australia. This indicates relatively recent transfer of M. ulcerans between these continents, which represent the vast majority of the global Buruli ulcer burden. Our data provide SNPs and gene sequences that can differentiate M. ulcerans lineages, suitable for use in the diagnosis and surveillance of Buruli ulcer.

Conclusions

M. ulcerans and all mycolactone-producing mycobacteria are specialized variants of a common Mycobacterium marinum progenitor that have adapted to live in restricted environments. Examination of genes lost or retained and now under selective pressure suggests these environments might be aerobic, and extracellular, where slow growth, production of an immune suppressor, cell wall remodeling, loss or modification of cell wall antigens, and biofilm-forming ability provide a survival advantage. These insights will guide our efforts to find the elusive reservoir(s) of M. ulcerans and to understand transmission of Buruli ulcer.
Which patients with lower respiratory tract infections need inpatient treatment? Perceptions of physicians, nurses, patients and relatives
Authors: Baehni Claudia , Meier Sabine , Spreiter Pamela , Schild Ursula , Regez Katharina , Bossart Rita , Thomann Robert , Falconnier Claudine , Christ-Crain Mirjam , De Geest Sabina , Müller Beat , Schuetz Philipp ,   the ProHOSP study group
Published: June 2012

Abstract

Background
Despite recommendations for outpatient management, low risk patients with lower respiratory tract infections (LRTIs) are often hospitalized. This survey analyzed perceptions of physicians, nurses, patients and relatives about feasibility of outpatient management and required duration of hospital stay.

Methods
We performed a prospective, observational questionnaire survey in hospitalized patients with LRTI as part of a multicenter trial. Treating physicians and nurses, patients and their relatives were asked on admission and before discharge about feasibility of outpatient treatment over 5 dimensions (medical, nursing, organizational factors, and patients' and relatives' preferences) using continuous scales.

Results
On admission, 12.6% of physicians, 15.1% of nurses, 18.0% of patients and 5.2% of relatives believed that outpatient treatment would be possible. Before hospital discharge, 31.1% of physicians, 32.2% of nurses, 11.6% of patients and 4.1% of relatives thought that earlier discharge would have been feasible. Medical factors were the most frequently perceived motives for inpatient management. These perceptions were similar in all LRTI subgroups and independent of disease severity and associated expected mortality risks as assessed by the Pneumonia Severity Index (PSI).

Conclusion
Independent of type and severity of respiratory tract infection, the misperceived high severity and expected mortality and morbidity were the predominant reasons why treating physicians, nurses, patients and their relatives unanimously believed that inpatient management was necessary. Better assessment and communication about true expected medical risks might contribute to a pathway to shorten in-hospital days and to introduce a more risk-targeted and individually tailored allocation of health-care resources.

Trial Registration
NCT00350987
Equine CTNNB1 and PECAM1 nucleotide structure and expression analyses in an experimental model of normal and pathological wound repair
Authors: Miragliotta Vincenzo , Ipiña Zoë , Lefebvre-Lavoie Josiane , Lussier Jacques G , Theoret Christine L 
Published: June 2012

AbstractBackgroundWound healing in horses is fraught with complications. Specifically, wounds on horse limbs often develop exuberant granulation tissue which behaves clinically like a benign tumor and resembles the human keloid in that the evolving scar is trapped in the proliferative phase of repair, leading to fibrosis. Clues gained from the study of over-scarring in horses should eventually lead to new insights into how to prevent unwanted scar formation in humans. cDNA fragments corresponding toCTNNB1(coding for β-catenin) andPECAM1, genes potentially contributing to the proliferative phase of repair, were previously identified in a mRNA expression study as being up-regulated in 7 day wound biopsies from horses. The aim of the present study was to clone full-length equineCTNNB1andPECAM1cDNAs and to study the spatio-temporal expression of mRNAs and corresponding proteins during repair of body and limb wounds in a horse model.ResultsThe temporal pattern of the two genes was similar; except forCTNNB1in limb wounds, wounding caused up-regulation of mRNA which did not return to baseline by the end of the study. Relative over-expression of bothCTNNB1andPECAM1mRNA was noted in body wounds compared to limb wounds. Immunostaining for both β-catenin and PECAM1 was principally observed in endothelial cells and fibroblasts and was especially pronounced in wounds having developed exuberant granulation tissue.ConclusionThis study is the first to characterize equine cDNA forCTNNB1andPECAM1and to document that these genes are expressed during wound repair in horses. It appears that β-catenin may be regulated in a post-transcriptional manner while PECAM1 might help thoracic wounds mount an efficient inflammatory response in contrast to what is observed in limb wounds. Furthermore, data from this study suggest that β-catenin and PECAM1 might interact to modulate endothelial cell and fibroblast proliferation during wound repair in the horse.
Surfactant-free ionic liquid-based nanofluids with remarkable thermal conductivity enhancement at very low loading of graphene
Authors: Wang Fuxian , Han Lijuan , Zhang Zhengguo , Fang Xiaoming , Shi Jingjing , Ma Wenshi 
Published: June 2012

Abstract
We report for the first time the preparation of highly stable graphene (GE)-based nanofluids with ionic liquid as base fluids (ionic liquid-based nanofluids (Ionanofluids)) without any surfactant and the subsequent investigations on their thermal conductivity, specific heat, and viscosity. The microstructure of the GE and MWCNTs are observed by transmission electron microscope. Thermal conductivity (TC), specific heat, and viscosity of these Ionanofluids were measured for different weight fractions and at varying temperatures, demonstrating that the Ionanofluids exhibit considerably higher TC and lower viscosity than that of their base fluids without significant specific heat decrease. An enhancement in TC by about 15.5% and 18.6% has been achieved at 25 °C and 65 °C respectively for the GE-based nanofluid at mass fraction of as low as 0.06%, which is larger than that of the MWCNT-dispersed nanofluid at the same loading. When the temperature rises, the TC and specific heat of the Ionanofluid increase clearly, while the viscosity decreases sharply. Moreover, the viscosity of the prepared Ionanofluids is lower than that of the base fluid. All these advantages of this new kind of Ionanofluid make it an ideal fluid for heat transfer and thermal storage.