bluuebunny/crossref_metadata_2025 huggingface dataset:
High Resolution/Accurate Mass Targeted Proteomics
Authors: Bourmaud A. , Gallien S. , Domon B.
Published: February 2014

Targeted proteomics has emerged as the predominant method for quantitative analyses of peptides to complement shotgun LC/MS studies. Targeted measurements are routinely performed using the technique of selected reaction monitoring (SRM) on triple quadrupole instruments. However, the approach suffers from limitations inherent to the SRM technique. First, the selectivity of measurements is often insufficient to effectively discriminate the analytes from the complex background commonly encountered in biological samples. Second, the number of peptides analyzed in one experiment remains limited. The recent development of high resolution/accurate mass instruments, in conjunction with various acquisition methods, has opened new avenues for quantitative proteomic studies. An overview of the analytical capabilities of a high resolution hybrid quadrupole–orbitrap instrument for quantitative applications is presented and discussed in this chapter. The measurements are performed either on precursor ions (selected ion monitoring mode) or on fragment ions (parallel reaction monitoring mode), which overcome, in many instances, the selectivity issue encountered in complex samples, as illustrated on various examples. It clearly demonstrates the potential of high resolution mass measurements for quantitative proteomic applications.
Proteomics Standards with Controllable Trueness—Absolute Quantification of Peptides, Phosphopeptides and Proteins Using ICP- and ESI-MS
Authors: Konopka Anna , Wild Christina , Boehm Martin E. , Lehmann Wolf D.
Published: February 2014

Novel methods for the generation of peptide, phosphopeptide and protein standards are described. Inductively coupled plasma mass spectrometry (ICP-MS) is used for quantitative detection, and electrospray ionization mass spectrometry (ESI-MS) is used for molecular characterization and purity control. Stable-isotope-labeled phosphopeptide standards are prepared by chemical synthesis with the introduction of phosphorus as an ICP-tag, and are accurately quantified using a combined y-split µLC-[ICP/ESI]-MS system. In addition, phosphopeptide standards can be used as the starting materials for the production of corresponding peptide standards via quantitative enzymatic dephosphorylation. This conversion step is controlled for completeness by ESI-MS. Stable-isotope-labeled protein standards are produced by cell-free synthesis with the stoichiometric introduction of selenium in the form of L-SeMet as an ICP-tag. The trueness of absolute standard quantification via ICP-MS and Se detection is not biased by the presence of other proteins since L-SeMet is exclusively present in the standard protein, where it replaces L-Met. RISQ (recombinant isotope-labeled and selenium quantified) protein standards contain both SeMet and stable-isotope-labeled amino acids of choice. Protein standards with SeMet but without stable isotope labels (recombinant selenium quantified, RSQ) and protein standards with only stable isotope labels (recombinant isotope-labeled and quantified, RIQ) are also described. In summary, the production of novel proteomics standards is proposed characterized by precision ≤5% and controllable trueness of their quantification.
Overview and Implementation of Mass Spectrometry-Based Label-Free Quantitative Proteomics
Authors: Soderblom Erik J. , Thompson J. Will , Moseley M. Arthur
Published: February 2014

Liquid chromatography coupled with mass spectrometry (LC-MS)-based quantitative proteomics has proven to be an invaluable tool to globally characterize proteins or peptides from complex biological systems. However, the methodology employed for mass spectrometry-based protein quantification remains an area of research interest. This chapter will provide an overview of LC-MS-based label-free quantification approaches, with a focus on a technical overview of the existing experimental practices in both spectral counting and ion intensity-based strategies. As both of these strategies are heavily dependent on informatics manipulation of the acquired data to extract the relevant quantitative information, a brief overview of current software solutions will be also discussed. The final portion of this overview will include a description of best-practice standard operating protocols and experimental design considerations when employing a label-free study. These general practices have been partially developed in our own laboratory over the course of several large-scale clinical studies and their routine incorporation into all of our quantitative workflows have resulted in a quantitatively robust and reproducible label-free platform.
MS1 Label-free Quantification Using Ion Intensity Chromatograms in Skyline (Research and Clinical Applications)
Authors: Schilling Birgit , MacLean Brendan X. , D'Souza Alexandria , Rardin Matthew J. , Shulman Nicholas J. , MacCoss Michael J. , Gibson Bradford W.
Published: February 2014

Skyline MS1 Filtering is a label-free quantitative software application that processes full-scan mass spectral data from proteomic experiments by extracting MS1 ion intensity chromatograms across multiple experiments. Key features include comprehensive graphical tools for inspection of MS1 peak picking, visualization of underlying MS/MS spectra, and automated peak integration with manual editing capabilities. Since the introduction of Skyline MS1 Filtering, both instrument vendor support and peptide search pipelines for building spectral libraries have been expanded. New features include run-to-run retention time alignment, time-scheduled import of ion chromatograms (using elution time windows), and facile linking with downstream statistical processing software tools required for high throughput processing of large proteomic discovery datasets. To demonstrate the suitability of MS1 Filtering for quantifying both research and clinical samples, we assessed the workflow reproducibility in monitoring a specific cancer target, receptor tyrosine-protein kinase (ErbB2). We also examined the utility of MS1 Filtering for identifying novel breast cancer biomarker candidates in discovery-based workflows. Taken together, these applications show Skyline MS1 Filtering to be a robust and sensitive approach for high throughput label-free quantification of data-dependent acquisitions. The MS1 Filtering workflow can be seamlessly integrated with selected reaction monitoring assay development within Skyline for further pre-clinical verification.
Spatial Proteomics: Practical Considerations for Data Acquisition and Analysis in Protein Subcellular Localisation Studies
Authors: Christoforou Andy , Mulvey Claire , Breckels Lisa M. , Gatto Laurent , Lilley Kathryn S.
Published: February 2014

Localisation of proteins within subcellular niches is a fundamental mechanism for the post-translational regulation of protein function. The high throughput and flexibility of quantitative mass spectrometry make it a highly complementary approach to the microscopy techniques typically used for such studies, although robust performance is dependent on accurate and precise quantification. In this chapter we review several proteomics methods that have been devised for this purpose, utilising label-free quantification, in vivo metabolic labelling, and isobaric tagging, and consider the strengths and limitations of their implementation.
Quantitative Analyses of Phosphotyrosine Cellular Signaling in Disease
Authors: Johnson Hannah
Published: February 2014

Tyrosine phosphorylation is a dynamic mechanism that has the potential to significantly alter the conformation, function and sub-cellular localizations of proteins. Identification of the site of post-translational modification and quantification of the levels of phosphorylation is essential to understand the functional significance of each phosphorylation site in biological systems. Increased sensitivity in mass spectrometry has recently allowed the quantification of hundreds of tyrosine phosphorylation sites across in vivo tissues and tumors. Furthermore, profiling phosphotyrosine signaling by mass spectrometry has led to greater insight into the function of tyrosine phosphorylation and, as such, it is clear that phosphotyrosine levels are significantly altered across many disease states. Thus, to gain a complete understanding of the mechanisms that lead to disease progression, it is important to identify deregulated proteins and genes and extend this to the identification of crucial changes at the signaling level. This chapter highlights the recent advances in quantitative phosphotyrosine analyses of relevant disease models and discusses the biological significance of these studies.
Mass Spectrometry-based Quantification of Proteins and Peptides in Food
Authors: Johnson Phil E. , Marsh Justin T. , Mills E. N. Clare
Published: February 2014

The application of quantitative proteomics to food analysis is in its infancy. This is partly due to the diverse range of plant and animal species consumed as foods, many of which are not sequenced, making annotation of food proteomes difficult. In addition food processing procedures and interactions with other food components, such as lipids and starch, introduce a diverse range of chemical and conformational changes to proteins, many of which are poorly defined. Mass spectrometry-based molecular profiling has great potential as quality assurance tool for food authenticity and traceability, safety and quality. A driver for the application of quantitative protein mass spectrometry-based methods to food has been the need to develop confirmatory methods for allergen analysis in support of food allergen labelling regulations. In addition to providing rigorous quantitative methodology for complex biomacromolecules, protein mass spectrometry is also allowing us, for the first time, to discover how processing procedures modify the foods we eat at a molecular level. Such knowledge is essential if we are to understand how food processing can be used to optimise the beneficial health effects of foods.
Compound identification in GC-MS by simultaneously evaluating the mass spectrum and retention index
Authors: Wei Xiaoli , Koo Imhoi , Kim Seongho , Zhang Xiang
Published: February 2014

We report a compound identification method (SimMR), which simultaneously evaluates the mass spectrum similarity and the retention index distance using an empirical mixture score function, for the analysis of GC-MS data.
Magnetic solid-phase extraction combined with in situ slurry cold vapor generation atomic fluorescence spectrometry for preconcentration and determination of ultratrace mercury
Authors: Zhang Wang-bing , Sun Chu-xiao , Yang Xin-an
Published: February 2014

A magnetic SPE method combined with CVG-AFS for the determination of Hg2+is established.
A disposable label-free electrochemiluminescent immunosensor for transferrin detection based on a luminol-reduced gold nanoparticle-modified screen-printed carbon electrode
Authors: Kong Weijun , Zhou He , Ouyang Hui , Li Zongyun , Fu Zhifeng
Published: February 2014

A disposable label-free electrochemiluminescent immunosensor based on luminol-reduced gold nanoparticles was designed for human transferrin detection.
A mild and selective Pd-mediated methodology for the synthesis of highly fluorescent 2-arylated tryptophans and tryptophan-containing peptides: a catalytic role for Pd0 nanoparticles?
Authors: Williams Thomas J. , Reay Alan J. , Whitwood Adrian C. , Fairlamb Ian J. S.
Published: February 2014

The C2-arylation of tryptophan derivatives, and small peptides containing tryptophan, is possible using a Pd/Cu co-catalyst system. The products are highly fluorescent, with potential for studying protein function.
Dendrimersomes: a new vesicular nano-platform for MR-molecular imaging applications
Authors: Filippi Miriam , Martinelli Jonathan , Mulas Gilberto , Ferraretto Marisa , Teirlinck Eline , Botta Mauro , Tei Lorenzo , Terreno Enzo
Published: February 2014

Vesicles formed by Janus dendrimers (dendrimersomes) loaded with hydrophilic or amphiphilic MRI probes show great potential as an efficient novel MRI nanosystem.
P2-type Na2/3Ni1/3Mn2/3−xTixO2 as a new positive electrode for higher energy Na-ion batteries
Authors: Yoshida Hiroaki , Yabuuchi Naoaki , Kubota Kei , Ikeuchi Issei , Garsuch Arnd , Schulz-Dobrick Martin , Komaba Shinichi
Published: February 2014

New electrode material of layered oxide, Na2/3Ni1/3Mn1/2Ti1/6O2, delivers 127 mA h g−1 of reversible capacity and the average voltage reaches 3.7 V with good capacity retention in an aprotic Na cell.
The effect of nitridation temperature on the structural, optical and electrical properties of GaN nanoparticles
Authors: Gopalakrishnan M. , Purushothaman V. , Ramakrishnan V. , Bhalerao G. M. , Jeganathan K.
Published: February 2014

Nitridation at high temperature enhances the crystalline and optical quality of GaN nanoparticles synthesized by a novel chemical co-precipitation method.
Solid state assembly of cyclic α-peptoids
Authors: Tedesco Consiglia , Erra Loredana , Izzo Irene , De Riccardis Francesco
Published: February 2014

In cyclic alpha-peptoids, inter-annular CH⋯OC hydrogen bonds provide face to face or side by side arrangement of macrocycles mimicking the beta-sheet secondary structure in proteins. Side chains may promote the formation of peptoid nanotubes, acting as pillars among neighbouring macrocycles.
Morphological evolutions and growth patterns of Zr-containing phases in aluminum alloys
Authors: Gao Tong , Cui Xiaoli , Li Xiongying , Li Hui , Liu Xiangfa
Published: February 2014

Increase of Si in Al–Si–Zr alloys causes evolution of structures, morphologies and growth patterns of Zr-containing phases.
Size- effect induced high thermoelectric figure of merit in PbSe and PbTe nanowires
Authors: Wrasse Ernesto O. , Torres Alberto , Baierle Rogério J. , Fazzio‡ Adalberto , Schmidt Tome M.
Published: February 2014

The fundamental properties that compose the thermoelectric figure of merit are investigated for PbSe and PbTe nanowires, and we find that the thermoelectric efficiency can be several times larger than the bulk efficiency.
Cyclic dipeptide immobilization on Au(111) and Cu(110) surfaces
Authors: Plekan Oksana , Feyer Vitaliy , Ptasińska Sylwia , Tsud Nataliya , Prince Kevin C.
Published: February 2014

Soft X-ray Photoelectron Spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy have been used to probe the electronic and adsorption properties of two cyclic dipeptides, i.e. cyclo(glycyl-histidyl) and cyclo(phenylalanyl-prolyl), on Au(111) and Cu(110) surfaces.
A TDDFT/MMPol/PCM model for the simulation of exciton-coupled circular dichroism spectra
Authors: Jurinovich Sandro , Pescitelli Gennaro , Di Bari Lorenzo , Mennucci Benedetta
Published: February 2014

A multiscale strategy is presented to simulate electronic CD spectra of multichromophoric systems using an excitonic approach in which all components are calculated self-consistently through a fully polarizable QM/MM/PCM method.
Association of nuisance filamentous algae Cladophora spp. with E. coli and Salmonella in public beach waters: impacts of UV protection on bacterial survival
Authors: Beckinghausen Aubrey , Martinez Alexia , Blersch David , Haznedaroglu Berat Z.
Published: February 2014

This study presents evidence of nuisance algae commonly found in public beach waters providing UV protection toE. coliandSalmonella.
The potential for a carbon stable isotope biomarker of dietary sugar intake
Authors: Jahren A. Hope , Bostic Joshua N. , Davy Brenda M.
Published: February 2014

Added sugar is sweetener added to foods during processing or preparation that offers no health benefits to the consumer.
The microstructure and melt properties of CO–ethylene copolymers with remarkably low CO content
Authors: Soomro Saeeda S. , Cozzula Daniela , Leitner Walter , Vogt Henning , Müller Thomas E.
Published: February 2014

Unique structure–property relationships were revealed for non-alternating polyketones obtained with unprecedented efficiency by a new protocol for the palladium-catalysed copolymerisation of CO and ethylene.
Tethering of spherical DOTAP liposome gold nanoparticles on cysteamine monolayer for sensitive label free electrochemical detection of DNA and transfection
Authors: Bhuvana Mohanlal , Dharuman Venkataraman
Published: February 2014

Cysteamine monolayer supported spherical DOTAP–AuNP on gold electrode is developed for DNA label free sensing and transfection.
Thermoelectric metal tellurides with nanotubular structures synthesized by the Kirkendall effect and their reduced thermal conductivities
Authors: Chai Zhanli , Wang Hui , Suo Quanyu , Wu Niri , Wang Xiaojing , Wang Cheng
Published: February 2014

Polycrystalline nanotubular Bi2Te3 and PbTe synthesized by the Kirkendall effect showed great decrease in thermal conductivities.
On the origin of the substantial stabilisation of the electron-donor 1,3-dithiole-2-thione-4-carboxyclic acid⋯I2and DABCO⋯I2complexes
Authors: Deepa Palanisamy , Sedlak Robert , Hobza Pavel
Published: February 2014

The stabilisation energies of the crystal structures of 1,3-dithiole-2-thione-4-carboxyclic acid⋯I2and DABCO⋯I2complexes determined by the CCSD(T)/CBS method are very large and exceed 8 and 15 kcal mol−1, respectively.
The reactivity game: theoretical predictions for heavy atom tunneling in adamantyl and related carbenes
Authors: Kozuch S.
Published: February 2014

What is the tunneling probability of carbon atoms? Can theory predict the “tunneling limit”?
Very small “window of opportunity” for generating CO oxidation-active Aun on TiO2
Authors: Tang X. , Schneider J. , Dollinger A. , Luo Y. , Wörz A. S. , Judai K. , Abbet S. , Kim Y. D. , Ganteför G. F. , Fairbrother D. H. , Heiz U. , Bowen K. H. , Proch S.
Published: February 2014

The probability of creating CO oxidation-active species on TiO2 is very small since only Au6 and Au7 are catalytically active.
Metal-free cross-coupling reaction of aldehydes with disulfides by using DTBP as an oxidant under solvent-free conditions
Authors: Zeng Jing-Wen , Liu Yi-Chen , Hsieh Ping-An , Huang Yu-Ting , Yi Chih-Lun , Badsara Satpal Singh , Lee Chin-Fa
Published: February 2014

A DTBP-promoted C–H thiolation of aldehydes with disulfides under metal-free and solvent-free conditions is described. The system shows good functional group tolerance to afford thioesters in moderate to excellent yields.
Tuning of symmetric send‐on‐delta proportional–integral controllers
Authors: Beschi Manuel , Dormido Sebastián , Sánchez José , Visioli Antonio
Published: February 2014

The tuning of the parameters of two types of event‐based proportional–integral (PI) controllers based on symmetric send‐on‐delta (deadband) sampling is investigated in this study. In particular, well‐known tuning rules devised for standard (continuous‐time) PI controllers are compared with tuning rules properly devised for these event‐based controllers in order to minimise the step response settling time. Simulations and experiments show that a satisfactory performance, namely, a performance similar to the corresponding time‐driven controller, is achieved by all the tuning rules considered because of the structure of the event‐based PI controller, thus making it very suitable for its use in the industry.
Image fusion using multiscale edge‐preserving decomposition based on weighted least squares filter
Authors: Jiang Yong , Wang Minghui
Published: February 2014

For pixel‐level image fusion, the edges of the source images should be as much as possible integrated into the fused image because the human visual system is sensitive to them. In this study, the authors utilise the multiscale edge‐preserving decomposition (MSEPD) based on the weighted least squares filter to fuse the source images. In the authors’ method, first, the source images are decomposed by the MSEPD into a base image and a series of detail images, respectively. Then, the detail images of same scale are combined via the different fusion rules designed for different kinds of source images; the base images are combined via the average‐value rule. Finally, the fused image is constructed by adding the fused base image and detail images together. The proposed fusion method is verified on several kinds of images and compared with some methods based on multiscale decomposition. The experimental results indicate that the proposed method can provide better fused images, meanwhile manifesting a good edge‐preserving performance.
The carbon and nitrogen cost associated with the growth, reproductive and dormant phases of two South African semi-arid geophytic species of Gethyllis (Amaryllidaceae)
Authors: Daniels Christiaan , Mabusela Wilfred , Marnewick Jeanine , Valentine Alexander
Published: February 2014

Gethyllis multifolia L.Bolus and G. villosa Thunb. (Family: Amaryllidaceae) are deciduous and bulbous geophytes that occur in the succulent Karoo biome of South Africa. Both species occupy the same natural habitat, but G. multifolia is threatened and G. villosa not. Both G. multifolia and G. villosa require seasonal bulb reserves for initial vegetative and reproductive growth. In spite of G. villosa having smaller bulbs than G. multifolia, both species produce similar flower sizes and weights. The aim of the present study was to determine the carbon and nitrogen costs of vegetative and reproductive growth during the phases of growth, senescence, reproduction and dormancy of these bulbous species. The rates, costs and efficiencies of biomass production during various growth phases of the two species were determined in a comparative experiment. The results show that in spite of a significantly smaller bulb, G. villosa produced more leaves per unit bulb mass and invested more carbon and nitrogen resources into the bulbs during senescence. G. villosa also had a higher flower production, relative to bulb weight, than did G. multifolia. These physiological responses suggest that G. villosa may be more efficient at carbon and nitrogen resource utilisation.
Mediating international and domestic demands: mnemonic battles surrounding the monument to the fallen of the wars of the 1990s in Belgrade
Authors: David Lea
Published: February 2014

In this article I present a decade-long affair over the erection of the Monument in Belgrade to those killed in the wars of the 1990s where the official Serbian policy was to manage its contested past through cover ups and cultural reframing rather than public acknowledgement. I demonstrate here that, though the open competitions to erect a monument dedicated to the fallen of the wars of the 1990s were an opportunity to negotiate different mnemonic agendas, the ruling political elite, as the dominant actor, promoted Serbian victimhood as it meant to bridge gaps in the opposing domestic and international demands. I suggest here that the mnemonic battle in present-day Serbia proves to be an exemplary case of how a post-conflict nation state mediates its contested past when caught in the gap between the domestic demands and those of international relations.
Existence and convergence to a propagating terrace in one-dimensional reaction-diffusion equations
Authors: Ducrot Arnaud , Giletti Thomas , Matano Hiroshi
Published: February 2014

We consider one-dimensional reaction-diffusion equations for a large class of spatially periodic nonlinearities – including multi-stable ones – and study the asymptotic behavior of solutions with Heaviside type initial data. Our analysis reveals some new dynamics where the profile of the propagation is not characterized by a single front, but by a layer of several fronts which we call a terrace. Existence and convergence to such a terrace is proven by using an intersection number argument, without much relying on standard linear analysis. Hence, on top of the peculiar phenomenon of propagation that our work highlights, several corollaries will follow on the existence and convergence to pulsating traveling fronts even for highly degenerate nonlinearities that have not been treated before.
Biological and Genetic Diversity of Wheat yellow mosaic virus (Genus Bymovirus)
Authors: Ohki Takehiro , Netsu Osamu , Kojima Hisayo , Sakai Junichi , Onuki Masatoshi , Maoka Tetsuo , Shirako Yukio , Sasaya Takahide
Published: February 2014

The biological and genetic diversity of Wheat yellow mosaic virus (WYMV) isolates in Japan was characterized. On the basis of wheat cultivar reactions, 14 WYMV isolates from various places were classified into pathotypes I, II, or III. These were distributed in central, northern, and southern areas of Japan, respectively. WYMV isolates comprised three genotypes (A, A′ and B) based on amino acid differences in RNA1 and two genotypes (a and b) based on amino acid differences in RNA2. A correlation was found between the WYMV RNA1-based genotype and pathotype, suggesting that factors associated with pathogenicity map to RNA1. Genotype Aa and A′a were distributed mainly in the central to southern areas of Japan, and genotype Bb was found in northern areas of Japan, as shown by reverse-transcription polymerase chain reaction restriction fragment length polymorphism analysis. Chinese isolates YA and YZ were closely related to genotypes Bb and Aa, respectively. Wheat was introduced from China to Japan in the 4th and 5th centuries, and the two genotypes of WYMV might also have been introduced with the crop from China and later adapted to local wheat cultivars in Japan.
Noradrenergic plasticity of olfactory sensory neuron inputs to the main olfactory bulb
Authors: Eckmeier D , Shea SD
Published: February 2014

Sensory responses are modulated throughout the nervous system by internal factors including attention, experience, and brain state. This is partly due to fluctuations in neuromodulatory input from regions such as the noradrenergic locus coeruleus (LC) in the brainstem. LC activity changes with arousal and modulates sensory processing, cognition and memory. The main olfactory bulb (MOB) is richly targeted by LC fibers and noradrenaline profoundly influences MOB circuitry and odor-guided behavior. Noradrenaline-dependent plasticity affects the output of the MOB. However, it is unclear whether noradrenergic plasticity includes modulation in the glomerular layer, the site of input to the MOB. Noradrenergic terminals are found in the glomerular layer, but noradrenaline receptor activation does not seem to acutely modulate olfactory sensory neuron terminalsin vitro. We investigated whether noradrenaline induces plasticity at the glomerulus. We used wide-field optical imaging to measure changes in odor responses following electrical stimulation of locus coeruleus in anesthetized mice. Surprisingly, the odor-evoked intrinsic optical signals at the glomerulus were persistently weakened after LC activation. Calcium imaging selectively from olfactory sensory neurons confirmed that this effect was due to a uniform gain suppression of presynaptic input, and did not require exposure to a stimulus during the LC activation. Finally, noradrenaline antagonists prevented glomerular suppression. We conclude that noradrenaline release from LC has persistent effects on odor processing already at the first synapse of the main olfactory system. This mechanism could contribute to arousal-dependent memories.
Femtosecond X-ray diffraction from two-dimensional protein crystals
Authors: Frank Matthias , Carlson David B. , Hunter Mark S. , Williams Garth J. , Messerschmidt Marc , Zatsepin Nadia A. , Barty Anton , Benner W. Henry , Chu Kaiqin , Graf Alexander T. , Hau-Riege Stefan P. , Kirian Richard A. , Padeste Celestino , Pardini Tommaso , Pedrini Bill , Segelke Brent , Seibert M. Marvin , Spence John C. H. , Tsai Ching-Ju , Lane Stephen M. , Li Xiao-Dan , Schertler Gebhard , Boutet Sebastien , Coleman Matthew , Evans James E.
Published: February 2014

X-ray diffraction patterns from two-dimensional (2-D) protein crystals obtained using femtosecond X-ray pulses from an X-ray free-electron laser (XFEL) are presented. To date, it has not been possible to acquire transmission X-ray diffraction patterns from individual 2-D protein crystals due to radiation damage. However, the intense and ultrafast pulses generated by an XFEL permit a new method of collecting diffraction data before the sample is destroyed. Utilizing a diffract-before-destroy approach at the Linac Coherent Light Source, Bragg diffraction was acquired to better than 8.5 Å resolution for two different 2-D protein crystal samples each less than 10 nm thick and maintained at room temperature. These proof-of-principle results show promise for structural analysis of both soluble and membrane proteins arranged as 2-D crystals without requiring cryogenic conditions or the formation of three-dimensional crystals.
Novel acoustic evaluation system for scratching behavior in itching dermatitis: Rapid and accurate analysis for nocturnal scratching of atopic dermatitis patients
Authors: Noro Yuichi , Omoto Youichi , Umeda Koji , Tanaka Futa , Shiratsuka Yousuke , Yamada Tomomi , Isoda Kenichi , Matsubara Kimiko , Yamanaka Keiichi , Gabazza Esteban C. , Nishikawa Masakatsu , Mizutani Hitoshi
Published: February 2014

Quantitative analysis of itching in patients with itching dermatitis including atopic dermatitis (AD) is indispensable for the evaluation of disease activity and response to therapy. However, the objective evaluation system for itching is limited. We have developed a new objective and quantitative scratching behavior detection system using a wristwatch‐type sound detector. The scratch sound detected on the wrist is recorded on a personal computer through a filtering, squaring and smoothing process by specific hardware. Subsequently, the data is automatically processed and judged for the scratching movement using specific software based on the periodicity and energy of the signal. Twenty‐four measurements for healthy volunteers and those with AD by this system were evaluated by comparison with a simultaneously recorded video analysis system. The ratio of scratching time in sleeping time evaluated by these two systems was almost identical. The healthy subjects scratched their skin approximately 2 min during 6 h of sleeping time, while the mean scratching time of AD subjects was 24 min in their sleeping time. In contrast to the time‐consuming video analysis system, this system takes only several minutes for evaluation of an overnight record. This scratch sound detection system is expected to serve as a new objective evaluation tool for itching dermatitis, namely, AD, and development of anti‐itch therapies for dermatitis.
Indications for caesarean sections at ≥34 weeks among nulliparous women and differential composite maternal and neonatal morbidity
Authors: Chauhan SP , Beydoun H , Hammad IA , Babbar S , Hill JB , Mlynarczyk M , D'Alton ME , Abuhamad AZ , Vintzileos AM , Ananth CV
Published: February 2014

Objective

To compare composite maternal and neonatal morbidities (CMM, CNM) among nulliparous women with primary indications for caesarean section (CS) as acute clinical emergency (group I; ACE), non‐reassuring fetal heart rate (group II) and arrest disorder (group III).

Design

A multicentre prospective study.

Setting

Nineteen academic centres in the USA, with deliveries in 1999–2002.

Population

Nulliparous women (n = 9829) that had CS.

Methods

Nulliparous women undergoing CS for three categories of indications were compared using logistic regression model, adjusted for five variables.

Main outcome measures

CMM was defined as the presence of any of the following: intrapartum or postpartum transfusion, uterine rupture, hysterectomy, cystotomy, ureteral or bowel injury or death; CNM was defined as the presence of any of the following: umbilical arterial pH <7.00, neonatal seizure, cardiac, hepatic, renal dysfunction, hypoxic ischaemic encephalopathy or neonatal death.

Results

The primary reasons for CS were ACE in 1% (group I, n = 114) non‐reassuring FHR in 29% (group II; n = 2822) and failed induction/dystocia in the remaining 70% (group III; n = 6893). The overall risks of CMM and CNM were 2.5% (95% confidence intervals, CI, 2.2–2.8%) and 1.9% (95% CI 1.7–2.2), respectively. The risk of CMM was higher in group I than in group II (RR 4.1, 95% CI 3.1, 5.3), and group III (RR 3.2, 95% CI 2.7, 3.7). The risk of CNM was also higher in group I than in group II (RR 2.8, 95% CI 2.3, 3.4) and group III (RR 14.1, 95% CI 10.7, 18.7).

Conclusions

Nulliparous women who have acute clinically emergent caesarean sections are at the highest risks of both composite maternal and neonatal morbidity and mortality.
Increased plasma advanced oxidation protein products is an early marker of endothelial dysfunction in type 2 diabetes patients without albuminuria 血浆晚期蛋白氧化产物浓度升高是无白蛋白尿的2型糖尿病患者内皮细胞功能异常的早期标志物
Authors: Liang Min , Wang Jun , Xie Chao , Yang Yan , Tian Jian Wei , Xue Yao Ming , Hou Fan Fan
Published: February 2014

Background

Endothelial dysfunction is an early event of cardiovascular disease in type 2 diabetes (T2D) and can occur before albuminuria. Oxidative stress has been found to play a key role in the development of endothelial dysfunction. Therefore, we hypothesized that increases in plasma advanced oxidized protein products (AOPPs), a family of oxidized, dityrosine‐containing protein compounds generated during oxidative stress, could serve as an early marker of endothelial dysfunction inT2Dpatients without albuminuria.

Methods

We conducted a cross‐sectional investigation of 147 newly diagnosedT2Dpatients (112 without albuminuria and 35 with albuminuria) and 49 age‐matched healthy control subjects. Flow‐mediated vasodilation (FMD) was used to assess endothelium‐dependent vasodilator function, and plasma soluble intercellular adhesion molecule‐1 (sICAM‐1) concentrations were determined to evaluate vascular injury. PlasmaAOPPsconcentrations were measured using a modified spectrophotometric assay.

Results

PlasmaAOPPsconcentrations were significantly elevated in normoalbuminuric patients withT2Dcompared with healthy controls. PlasmaAOPPsconcentrations were correlated withFMDand plasmasICAM‐1 concentrations in this population. Multivariate regression analysis demonstrated that increased plasmaAOPPswas the strongest risk factor for impaired endothelial vasodilation and increasedsICAM‐1 in these patients. Similar results were observed inT2Dpatients with albuminuria.

Conclusions

Increased plasmaAOPPsconcentrations were an independent risk factor for endothelial dysfunction, and therefore may be an early marker of vasculopathy in individuals at an early stage of diabetes.
Autonomic dysfunction assessed by EZSCAN and subclinical atherosclerosisEZSCAN 检测自主神经功能紊乱与亚临床动脉粥样硬化相关性研究
Authors: Sun Jichao , Zhang Yinfei , Xu Baihui , Lv Xiaofei , Ding Lin , Chen Ying , Sun Wanwan , Lu Jieli , Xu Min , Bi Yufang , Ning Guang
Published: February 2014

Background

The present study aimed to explore the association between autonomic dysfunction and measurements of atherosclerosis in a middle‐aged and elderly Chinese population.

Methods

A population‐based cross‐sectional study was performed in Shanghai, China, from March to August 2010, with 5076 participants included in the analysis. Autonomic function was assessed by a novel EZSCAN test based on sudomotor function analysis. Carotid intima–media thickness (CIMT) was measured using B‐mode ultrasonography and brachial–ankle pulse wave velocity (ba‐PWV) was measured using an autonomic device. Participants were divided into three groups based on EZSCAN values: Group 1: EZSCAN 0–24; Group 2, EZSCAN 25–49; and Group 3, EZSCAN 50–100. These groups denoted autonomic dysfunction risk groups as follows: no risk, moderate risk and high risk, respectively.

Results

The prevalence of elevated CIMT and ba‐PWV increased markedly with increasing EZSCAN values (elevated CIMT 7.4%, 17.5%, and 29.7%, elevated ba‐PWV 3.2%, 19.7%, and 36.5%, in Groups 1, 2, and 3, respectively; both Ptrend < 0.0001). Logistic regressions revealed that EZSCAN values ≥50 were associated with a non‐significantly higher risk of elevated CIMT (odds ratio [OR] = 1.43; 95% confidence interval [CI] 0.98–2.07) and a significantly higher risk of elevated ba‐PWV (OR = 2.16; 95% CI 1.25–3.71) compared with EZSCAN values <25, after controlling for conventional risk factors.

Conclusion

A higher EZSCAN value (≥50), an index of high autonomic dysfunction risk, was associated with an increased risk of elevated ba‐PWV and CIMT. Such associations were partially explained by traditional atherosclerotic risk factors.
A Randomized Trial Exploring the Effect of a Telephone Call Follow‐up on Care Plan Compliance Among Older Adults Discharged Home From the Emergency Department
Authors: Biese Kevin , LaMantia Michael , Shofer Frances , McCall Brenda , Roberts Ellen , Stearns Sally C. , Principe Stephanie , Kizer John S. , Cairns Charles B. , Busby‐Whitehead Jan
Published: February 2014

Objectives

Older patients discharged from the emergency department (ED) have difficulty comprehending discharge plans and are at high risk of adverse outcomes. The authors investigated whether a postdischarge telephone call–mediated intervention by a nurse would improve discharge care plan adherence, specifically by expediting post–ED visit physician follow‐up appointments and/or compliance with medication changes. The second objectives were to determine if this telephone call intervention would reduce return ED visits and/or hospitalizations within 35 days of the index ED visit and to determine potential cost savings of this intervention.

Methods

This was a 10‐week randomized, controlled trial among patients aged 65 and older discharged to home from an academic ED. At 1 to 3 days after each patient's index ED visit, a trained nurse called intervention group patients to review discharge instructions and assist with discharge plan compliance; placebo call group patients received a patient satisfaction survey call, while the control group patients were not called. Data collection calls occurred at 5 to 8 days and 30 to 35 days after the index ED visits for all three groups. Chi‐square or Fisher's exact tests were performed for categorical data and the Kruskal‐Wallis test examined group differences in time to follow‐up.

Results

A total of 120 patients completed the study. Patients were 60% female and 72% white, with a mean age of 75 years (standard deviation [SD] ± 7.58 years). Intervention patients were more likely to follow up with medical providers within 5 days of their ED visits than either the placebo or the control group patients (54, 20, and 37%, respectively; p = 0.04). All groups performed well in medication acquisition and comprehension of medication indications and dosage. There were no differences in return visits to the ED or hospital within 35 days of the index ED visit for intervention patients, compared to placebo or control group patients (22, 33, and 27%, respectively; p = 0.41). An economic analysis showed an estimated 70% chance that this intervention would reduce total costs.

Conclusions

Telephone call follow‐up of older patients discharged from the ED resulted in expedited follow‐up for patients with their primary care physicians. Further study is warranted to determine if these results translate into improved patient outcomes, decreased return ED visits or hospital admissions, and cost savings resulting from this intervention.
The Microcirculation Is Preserved in Emergency Department Low‐acuity Sepsis Patients Without Hypotension
Authors: Filbin Michael R. , Hou Peter C. , Massey Michael , Barche Apurv , Kao Erica , Bracey Alex , Skibsted Simon , Chang Yuchiao , Shapiro Nathan I.
Published: February 2014

Objectives

Microcirculatory dysfunction plays an important role in sepsis pathophysiology. Previous studies using sidestream dark‐field (SDF) imaging have demonstrated microcirculatory flow abnormalities in patients with septic shock; however, the microcirculation is relatively unstudied in lower‐acuity sepsis patients. The hypothesis was that patients with sepsis, but without hypotension, will demonstrate signs of flow abnormalities compared to noninfected control patients.

Methods

This was a prospective, observational study in a convenience sample of patients with sepsis and noninfected controls, conducted in three urban, tertiary care emergency departments (EDs) in the United States. Sepsis was defined as suspected infection plus two or more systemic inflammatory response syndrome (SIRS) criteria; those with hypotension were excluded. Noninfected controls were ED patients without infection and without SIRS criteria. SDF imaging was obtained in all study patients during ED evaluation. Recommended microcirculatory flow parameters were measured, and the difference in these measures between sepsis patients and noninfected controls were calculated. The authors also correlated microcirculatory flow parameters with patient variables, including serum lactate.

Results

A total of 106 patients were enrolled: 63 with sepsis and 43 noninfected controls. There were no differences in microcirculatory flow scores between sepsis patients and noninfected controls. Median microvascular flow index (MFI; with interquartile range [IQR] was 3.00 (IQR = 2.73 to 3.00) in sepsis patients versus 2.93 (IQR = 2.73 to 3.00) in control patients (p = 0.33), and mean proportion of perfused small vessels (PPV) was 91.5% (95% CI = 89.7% to 93.3%) versus 91.8% (95% CI = 89.7% to 93.9%), with a mean difference of 0.3% (95% CI = –2.5% to 3.1%; p = 0.84). Similarly, there were no significant differences in total vessel density, perfused vessel density, or heterogeneity index (HI). In the subset of infected patients for whom serum lactates were obtained (n % 37), MFI and PPV were negatively correlated with elevated serum lactate values: r = –0.32, p = 0.04; and r = –0.44, p < 0.01, respectively.

Conclusions

Measureable microcirculatory flow abnormalities were not observed in patients with early sepsis in the absence of hypotension. However, microcirculatory abnormalities were correlated with elevated serum lactate in normotensive sepsis patients, supporting the notion that impaired microcirculatory flow is coupled with cellular distress.
Procalcitonin as a Marker of Serious Bacterial Infections in Febrile Children Younger Than 3 Years Old
Authors: Mahajan Prashant , Grzybowski Mary , Chen Xinguang , Kannikeswaran Nirupama , Stanley Rachel , Singal Bonita , Hoyle John , Borgialli Dominic , Duffy Elizabeth , Kuppermann Nathan
Published: February 2014

Objectives

There is no perfectly sensitive or specific test for identifying young, febrile infants and children with occult serious bacterial infections (SBIs). Studies of procalcitonin (PCT), a 116‐amino‐acid precursor of the hormone calcitonin, have demonstrated its potential as an acute‐phase biomarker for SBI. The objective of this study was to compare performance of serum PCT with traditional screening tests for detecting SBIs in young febrile infants and children.

Methods

This was a prospective, multicenter study on a convenience sample from May 2004 to December 2005. The study was conducted in four emergency departments (EDs): one pediatric ED and three EDs with pediatric units, all with academic faculty on staff. A total of 226 febrile children 36 months old or younger who presented to the four participating EDs and were evaluated for SBI by blood, urine, and/or cerebral spinal fluid (CSF) cultures were included.

Results

The test characteristics (with 95% confidence intervals [CIs]) of the white blood cell (WBC) counts including neutrophil and band counts were compared with PCT for identifying SBI. Thirty children had SBIs (13.3%, 95% CI = 8.85 to 17.70). Four (13.3%) had bacteremia (including one with meningitis), 18 (60.0%) had urinary tract infections (UTIs), and eight (26.6%) had pneumonia. Children with SBIs had higher WBC counts (18.6 × 109 ± 8.6 × 109 cells/L vs. 11.5 × 109 ± 5.3 × 109 cells/L, p < 0.001), higher absolute neutrophil counts (ANCs; 10.6 × 109 ± 6.7 × 109 cells/L vs. 5.6 × 109 ± 3.8 × 109 cells/L, p = 0.009), higher absolute band counts (0.90 × 109 ± 1.1 × 109 cells/L vs. 0.35 × 109 ± 0.6 × 109 cells/L, p = 0.009), and higher PCT levels (2.9 ± 5.6 ng/mL vs. 0.4 ± 0.8 ng/mL, p = 0.021) than those without SBIs. In a multivariable logistic regression analysis, the absolute band count and PCT were the two screening tests independently associated with SBI, although the area under the receiver operating characteristic (ROC) curve for PCT was the largest (0.80, 95% CI = 0.71 to 0.89).

Conclusions

Procalcitonin is a more accurate biomarker than traditional screening tests for identifying young febrile infants and children with serious SBIs. Further study on a larger cohort of young febrile children is required to definitively determine the benefit of PCT over traditional laboratory screening tests for SBIs.
The Effect of Point‐of‐care Ultrasonography on Emergency Department Length of Stay and Computed Tomography Utilization in Children With Suspected Appendicitis
Authors: Elikashvili Inna , Tay Ee Tein , Tsung James W.
Published: February 2014

Objectives

The role of clinician‐performed ultrasonography (US) for suspected appendicitis is unclear. Published data conclude that US has high specificity to rule in the diagnosis of appendicitis, with variable sensitivity to rule it out. Newer data suggest that point‐of‐care (POC) US may have similar test characteristics. Our objective was to evaluate the effect of POC US in children with suspected appendicitis and its effect on emergency department (ED) length of stay (LOS) and computed tomography (CT) utilization.

Methods

This was a prospective observational convenience sample of children with suspected appendicitis requiring imaging evaluation that adhered to the Standards for the Reporting of Diagnostic accuracy studies (STARD) criteria. Outcomes were determined by operative or pathology report in those who had appendicitis, and 3‐week phone follow‐up in those patients who were nonoperative. Differences in ED LOS were analyzed by one‐way analysis of variance (ANOVA) between patients who received dispositions after POC US, radiology US, or CT. Test performance characteristics were calculated for all imaging modalities.

Results

Among 150 enrolled patients, 50 had appendicitis (33.3%). There were no missed cases of appendicitis in discharged patients at 3‐week phone follow‐up, nor negative laparotomies in those who went to the operating room. Those who had dispositions after POC US (n = 25) had a significantly decreased mean ED LOS (154 minutes, 95% confidence interval [CI] = 115 to 193 minutes) compared with those requiring radiology US (288 minutes, 95% CI = 257 to 319 minutes) or CT scan (487 minutes; 95% CI = 434 to 540 minutes). Baseline CT rate was 44.2% (95% CI = 30.7% to 57.7%) prior to study start and decreased to 27.3% (95% CI = 20.17% to 34.43%) during the study. CTs were avoided in four patients with conclusive POC US results and inconclusive radiology US results. The sensitivity, specificity, positive likelihood ratio (LR+), and negative likelihood ratio (LR–) for POC US were 60% (95% CI = 46% to 72%), 94% (95% CI = 88% to 97%), 10 (95% CI = 4 to 23), and 0.4 (95% CI = 0.3 to 0.6). For radiology US they were 63% (95% CI = 48% to 75%), 99% (95% CI = 94% to 99%), 94 (95% CI = 6 to 1,500), and 0.4 (95% CI = 0.3 to 0.6); and for CT they were 83% (95% CI = 58% to 95%), 98% (95% CI = 85% to 99%), 45 (95% CI = 3 to 707), and 0.2 (95% CI = 0.05 to 0.5).

Conclusions

It may be feasible to reduce ED LOS and avoid CT scan when using POC US to evaluate children with suspected appendicitis. Test characteristics for POC US have high specificity to rule in appendicitis, similar to radiology US. Addition of POC US prior to sequential radiology imaging was safe, without missed cases of appendicitis or negative laparotomies.