bluuebunny/crossref_metadata_2025_split huggingface dataset:
An international perspective on the regulation of biosamples
Authors: Ellson Sarah 
Published: March 2012

AbstractThis presentation will provide an additional perspective to that of the scientific and ethical issues that surround biosamples, by considering the appropriate role of regulation in this area. A regulatory regime can be used to ensure that the individuals, organisations and activities are governed in such a way as to ensure the highest ethical and scientific standards are maintained. Right touch regulation should promote innovation and should not be overly burdensome, but it is required to ensure that, in the highly sensitive area of biosampling, there is an appropriate framework in which high calibre operators can function and unsafe or unethical practise is prevented. As stem cell and biosample banking expands into new scientific and geographic areas regulation has to be sufficiently flexible to adapt to the unknown. It is also required if the bio banking communities are going to operate internationally.The presentation will consider what the international community might expect to see in regulatory terms as the Middle East expands into these opportunities. Regulation should be understood as key to ensuring confidence in the processes involved in biosampling. The presentation will look at some of the regulatory issues and challenges encountered in Europe and beyond and discuss the perspective and lessons to be learned. Central to the discussion will be consent issues and how consent may be embedded in regulation to underpin approaches to the storage, import and export and research with human tissue and cells.
Generation of red blood cells from pluripotent stem cells as an alternative to donated blood
Authors: Mountford Joanne 
Published: March 2012

AbstractWe are working to generate human red blood cells from human pluripotent stem cells at sufficient levels of quality and safety to warrant entry to pre-clinical and clinical studies. These in vitro generated red blood cells (RBCs) offer an alternative to donated blood and may be of particular use for patients receiving repeated red cell transfusions including those with sickle cell disease and thalassaemias. In order to generate RBCs suitable for clinical use we have derived 10 new clinical grade GMP human embryonic stem cell lines. Our erythroid differentiation protocol is suspension culture based with no co-culture. The protocol, which lasts 24 days, achieves ~20,000 fold expansion in cell numbers and results in ~95% of the cells in culture expressing erythroid markers (glycophorin A, CD71, CD36)and having the characteristic morphology of haemoglobinised normoblasts. HPLC and quantitative PCR analysis of globin chains show that fetal alpha and gamma chains predominate with embryonic epsilon and zeta chains only comprising >5% of total globins. Minimal spontaneous enucleation (≤5%) has observed, however, nucleated erythroid cells examined for their ability to bind and release oxygen (in a Hemox Analyser) demonstrated a similar profile to cord blood derived RBCs, consistent with the presence of fetal haemoglobin in these cells. We are currently testing our differentiation protocol with induced pluripotent stem cells (iPSC) and dissecting the molecular profile of the hESC-derived day 24 normoblast population in order to better understand why these cells do not enucleate as readily as adult haematopoietic stem cell derived erythrocytes. In addition to these remaining biological issues, we are addressing the processes needed for GMP-grade scale up of the protocol to facilitate the production of large numbers of clinically acceptable RBCs.J. C. Mountford1,4, D. Anstee2, A. Courtney6, L. Forrester4, W. Murphy3, S. Parsons2, P. de Sousa6,5 and M.L Turner1. Scottish National Blood Transfusion Service1, NHS Blood and Transplant2, Irish Blood Transfusion Service3, University of Glasgow4, University of Edinburgh5 and Roslin Cells Ltd6. United Kingdom.
Confirmation of drug delivery after liver chemoembolization: direct tissue doxorubicin measurement by UHPLC‐MS‐MS
Authors: Baumgarten Sigrid , Gaba Ron C. , van Breemen Richard B. 
Published: March 2012

ABSTRACTBecause liver cancer is rarely suitable for surgery, transcatheter arterial chemoembolization (TACE) is used for palliative therapy. In this procedure, an emulsion of doxorubicin in iodized oil is injected directly into liver tumors through a catheter positioned within the artery supplying blood flow to the tumor. At present, there is limited understanding of factors affecting the delivery and dispersion of doxorubicin within treated tumors during TACE. This study addresses the development and application of an ultrahigh‐pressure liquid chromatography–tandem mass spectrometry (UHPLC‐MS‐MS) method for rapid confirmation of drug delivery after TACE in a rabbit VX2 liver cancer model. Doxorubicin levels in liver tumors were measured using UHPLC‐MS‐MS and compared with computed tomography measured levels of iodized oil, a metric used clinically to indicate drug delivery. We found that tissue drug levels determined using UHPLC‐MS‐MS did not correlate with the regional iodized oil concentration (vehicle) within tumors following TACE, suggesting that chemotherapeutic drugs like doxorubicin spread throughout tumors, and that lack of iodized oil staining in portions of a tumor does not necessarily indicate inadequate therapy during TACE. Copyright © 2012 John Wiley & Sons, Ltd.
Nitraminoazoles Based on ANTA – A Comprehensive Study of Structural and Energetic Properties
Authors: Dippold Alexander A. , Klapötke Thomas M. , Martin Franz A. , Wiedbrauk Sandra 
Published: March 2012

AbstractSince 5‐Amino‐3‐nitro‐1H‐1,2,4‐triazole (ANTA) is known to be a thermally very stable secondary explosive, our goal in this contribution was the synthesis of thermally stable but more powerful energetic compounds based on ANTA. Hence, we utilized ANTA to synthesize 5‐nitramino‐3‐nitro‐1H‐1,2,4‐triazole (1) by nitration with a mixture of concentrated sulfuric acid and 100 % nitric acid. ANTA was also methylated with dimethyl sulfate to yield 5‐amino‐1‐methyl‐3‐nitro‐1,2,4‐triazole (2), which was then subsequently nitrated by using the method mentioned above to yield 1‐methyl‐5‐nitramino‐3‐nitro‐1,2,4‐triazole (3). All three compounds were characterized by IR and Raman as well as multinuclear NMR spectroscopy. Additionally, X‐ray crystallographic measurements of 1 and 3 were performed. The decomposition points of the compounds were found to be low for 1 (135 °C) and 3 (108 °C), despite the high thermal stability of ANTA (>220 °C) and 2 (294 °C). In order to increase the thermal stability of the compounds, nitrogen‐rich salts of 1 and 3 with the ammonium, hydrazinium, guanidinium, aminoguanidinium, and triaminoguanidinium cations were prepared and fully characterized by means of vibrational and NMR spectroscopy, DSC measurements, and X‐ray diffraction measurements. Additionally, the impact as well as friction sensitivities and the sensitivity against electrostatic discharge were determined by using standard BAM techniques. The standard heats of formation were calculated for selected compounds at the CBS‐4M level of theory, which reveals high positive heats of formation for all compounds.
Holding back the microfilament—Structural insights into actin and the actin‐monomer‐binding proteins of apicomplexan parasites
Authors: Olshina Maya A. , Wong Wilson , Baum Jake 
Published: March 2012

AbstractParasites from the phylum Apicomplexa are responsible for several major diseases of man, including malaria and toxoplasmosis. These highly motile protozoa use a conserved actomyosin‐based mode of movement to power tissue traversal and host cell invasion. The mode termed as ‘gliding motility’ relies on the dynamic turnover of actin, whose polymerisation state is controlled by a markedly limited number of identifiable regulators when compared with other eukaryotic cells. Recent studies of apicomplexan actin regulator structure—in particular those of the core triad of monomer‐binding proteins, actin‐depolymerising factor/cofilin, cyclase‐associated protein/Srv2, and profilin—have provided new insights into possible mechanisms of actin regulation in parasite cells, highlighting divergent structural features and functions to regulators from other cellular systems. Furthermore, the unusual nature of apicomplexan actin itself is increasingly coming into the spotlight. Here, we review recent advances in understanding of the structure and function of actin and its regulators in apicomplexan parasites. In particular we explore the paradox between there being an abundance of unpolymerised actin, its having a seemingly increased potential to form filaments relative to vertebrate actin, and the apparent lack of visible, stable filaments in parasite cells. 2012 IUBMB IUBMB Life, 2012
Supramolecular Synthesis of Graphenic Mesogenic Materials
Authors: Guo Fei , Hurt Robert 
Published: March 2012

AbstractSupramolecular chemistry offers new routes for creation of carbon and graphene‐based materials with precise control of structure. This approach stacks, aligns, polymerizes, or otherwise directs the assembly of precursor molecules into non‐covalent superstructures or macromolecular intermediates that are then chemically converted to carbon. A subset of this field uses liquid crystal phases, or mesophases, which exhibit orientational molecular order somewhere along the chemical trajectory to carbon. Covalent capture of that orientational order followed by heteroatom removal leads to “mesogenic graphenic materials”. This review article addresses these carbons and focuses on new methods and materials that use well‐defined molecular precursors. It discusses polyaromatic compounds as starting materials, assembly modes in the melt and solvent phases, and potential applications.
High‐resolution matrix‐assisted laser desorption/ionization imaging of tryptic peptides from tissue
Authors: Schober Yvonne , Guenther Sabine , Spengler Bernhard , Römpp Andreas 
Published: March 2012

RATIONALEThe analysis of proteins by mass spectrometry imaging is an important biomedical application as spatial distributions can be used to identify markers for pathological processes. The direct detection and identification of proteins on tissue can be hindered by a number of factors including limited mass range and fragmentation efficiency as well as incompatibility with formalin‐fixed samples.METHODSTo overcome some of these limitations, on‐tissue digestion of proteins was followed by detection of the resulting peptides. Trypsin was applied by a spraying device. Matrix‐assisted laser desorption/ionization (MALDI) imaging experiments were performed with a home‐built atmospheric‐pressure imaging source attached to a LTQ Orbitrap mass spectrometer. The mass accuracy under imaging conditions was better than 3 ppm RMS. This allowed for confident identification of tryptic peptides by comparison with liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) measurements of an adjacent mouse brain section.RESULTSA spatial resolution of 50 µm was obtained for tryptic peptides on tissue. Several tryptic peptides of myelin showed matching spatial distributions, and numerous tryptic peptides of other proteins were identified. MS images were generated with a bin size (mass range used for image generation) of Δm/z = 0.01 u. Examples demonstrate that MS images with lower selectivity can result in misleading information about the spatial distribution of tryptic peptides.CONCLUSIONSThe presented method combines a significantly improved spatial resolution for tryptic peptides with low‐ppm mass accuracy in a single experiment and thus provides highly reliable and specific information. Copyright © 2012 John Wiley & Sons, Ltd.
Spectral accuracy of a new hybrid quadrupole time‐of‐flight mass spectrometer: application to ranking small molecule elemental compositions
Authors: Jiang Wei , Erve John C. L. 
Published: March 2012

RATIONALEDetermining the elemental compositions of unknown molecules is an important goal of analytical chemistry. The isotope pattern revealed by a mass spectrometer provides valuable information regarding the elemental composition of a molecule. In order to employ spectral accuracy considerations for elemental composition determination, it is important to know how faithfully a mass spectrometer can record the isotope pattern and to understand the magnitude of the errors of the relative isotopic abundances.METHODSTwenty‐four small molecule drugs and two natural products representing a diverse range of elemental compositions and ranging in molecular weight from 236 to 1663 Da were measured on a new hybrid orthogonal acceleration quadrupole time‐of‐flight (Q‐TOF) mass spectrometer by flow infusion analysis. The similarity between the observed profile isotope pattern and the theoretical isotope pattern, denoted spectral accuracy, was calculated using a computational algorithm in the program MassWorks.RESULTSThe spectral accuracy for all compounds averaged better than 98%. When using spectral accuracy to rank elemental compositions with the elemental constraints (C1–100H0–200N0–50O0–50F0–5S0–5Cl0–5Br0–5) further restricted by empirical rules and a mass tolerance ≤5 parts‐per‐million, the correct formula was ranked first over 80% of the time. In contrast, when using mass accuracy for ranking, only two compounds (8%) were ranked first. For quinidine and troglitazone, the initial spectral accuracy measurements were lower than expected and further analysis indicated that minor, structurally related components were present.CONCLUSIONSOur work has determined the magnitude of spectral accuracy that can be expected on a new Q‐TOF mass spectrometer. In addition, we demonstrate the utility of spectral accuracy measurements both for ranking elemental compositions and also for obtaining insight into the chemical nature of the analyte that might otherwise be overlooked. Copyright © 2012 John Wiley & Sons, Ltd.
A liquid chromatography/tandem mass spectrometry method for measuring the in vivo incorporation of plasma free fatty acids into intramyocellular ceramides in humans
Authors: Blachnio‐Zabielska Agnieszka U. , Persson Xuan‐Mai T. , Koutsari Christina , Zabielski Piotr , Jensen Michael D. 
Published: March 2012

RATIONALESphingolipids are important components of cell membranes that serve as cell signaling molecules; ceramide plays a central role in sphingolipid metabolism. De novo ceramide biosynthesis depends on fatty acid availability, but whether muscle uses circulating free fatty acids or pre‐existing intracellular stores is unknown. Our goal was to develop a method to detect the incorporation of intravenously infused [U‐13C]palmitate into intramyocellular ceramides.METHODSWe used liquid chromatography/tandem mass spectrometry (LC/MS/MS) to measure the concentrations of different sphingolipid species and 13C‐isotopic enrichment of 16:0‐ceramide. Chromatographic separation was performed using ultra‐performance liquid chromatography. The analysis was performed on a triple quadrupole mass spectrometer using a positive ion electrospray ionization source with selected reaction monitoring (SRM).RESULTSThe sphingolipids ions, except enriched ceramide, were monitored as [M+2+H]+. The [13C16]16:0‐ceramide was monitored as [M+16+H]+. By monitoring two different transitions of the [13C16]16:0‐ceramide (554/536 and 554/264) we could indirectly measure enrichment of the palmitate that is not a part of the sphingoid base. Concentration and enrichment could be measured using 20 mg of muscle obtained from volunteers receiving a low dose [U‐13C]palmitate infusion.CONCLUSIONSLC/MS/MS can be used to detect the incorporation of plasma palmitate into muscle ceramides in humans, in vivo. Copyright © 2012 John Wiley & Sons, Ltd.
Elements of a theory for multiparton interactions in QCD
Authors: Diehl Markus , Ostermeier Daniel , Schäfer Andreas 
Published: March 2012

Abstract
We perform a detailed investigation of multiple hard interactions in hadron-hadron collisions. We discuss the space-time, spin and color structure of multiple interactions, classify different contributions according to their power behavior and provide several elements required for establishing all-order factorization. This also allows us to analyze the structure of Sudakov logarithms in double hard scattering. We show how multiparton distributions can be constrained by connecting them with generalized parton distributions and by calculating their behavior at large transverse parton momenta.
Resource productivity and availability impacts for food‐chain length
Authors: Doi Hideyuki 
Published: March 2012

AbstractEcologists have focused on food‐chain length (FCL) for the past eight decades as an index of food‐web structure. Here, I review the hypotheses determining FCL with a focus on resource productivity and availability effects on FCL. First, I introduce the mainstream hypotheses to explain FCL variations: productivity, ecosystem size, and disturbance. For the existing productivity and productive space hypotheses, I stress the importance of using resource availability to estimate the productivity effect on FCL. Using a FCL dataset from 15 ponds, I tested the resource stoichiometry effect on FCL for ponds with between carbon:nitrogen ratio of primary producers and FCL. Moreover, I provide a perspective for studying resource availability and stoichiometry effects on FCL and of the alternative hypotheses of productive‐space and ecosystem size. Finally, I suggest the future directions of the FCL study: a resource subsidy and climate change effects on FCL and food‐web structure.
Patient-Reported Outcomes after Acute Carpal Tunnel Release in Patients with Distal Radius Open Reduction Internal Fixation
Authors: Chauhan Aakash , Bowlin Timothy C. , Mih Alexander D. , Merrell Gregory A. 
Published: March 2012

Background Acute carpal tunnel syndrome (CTS) is a complication that can develop after distal radius fractures. Our hypothesis tested whether patient-reported outcomes after acute carpal tunnel release (CTR) performed in combination with distal radius fracture open reduction internal fixation (ORIF) are worse than patient-reported outcomes with only elective CTR as measured by the symptom severity and functional status scales of the Boston carpal tunnel questionnaire (BCTQ). Methods A retrospective assessment identified 26 patients treated with acute CTR at the same time as distal radius ORIF, no history of pre-existing CTS or CTR, no other injuries, and >12 months follow-up. Sixteen of these patients (Group A) could be contacted and answered the BCTQ. Group A was age- and sex-matched to control patients (Group B) treated with only elective CTR. A case–control study was performed comparing outcomes of both groups. Results The average age of patients was 51±15 years, with an average follow-up of Group A at 49±21 months versus Group B at 55±20 months. The mean symptom severity scale score for Group A was 1.4±0.4 and for Group B was 1.4±0.4. The mean functional status scale score for Group A was 1.4±0.5 and for Group B was 1.3±0.4. The mean total BCTQ score for Group Awas 26.5±7.5 and for Group B was 24.9±7.5. There were no statistical or clinically significant differences between Group A and Group B for symptom severity, functional status, and total BCTQ scores. Conclusions Patients with acute CTR performed at the same time with distal radius ORIF do as well in the long-term as those patients with only elective CTR as measured by the BCTQ. Patients should expect similar recovery of subjective nerve function from acute median nerve dysfunction when CTR is performed with distal radius ORIF as patients with only elective CTR.
Properties of Sodium Methyl Ester Alpha‐Sulfo Alkylate/Trimethylammonium Bromide Mixtures
Authors: Wong Siew Pui , Lim Wen Huei , Cheng Sit‐Foon , Chuah Cheng Hock 
Published: March 2012

AbstractThe surface properties of binary mixtures of anionic sodium methyl ester α‐sulfo alkylate (CmMES) and cationic alkyl trimethylammonium bromide (CnTAB) of different carbon chain length have been studied in the present work. The critical micelle concentration (CMC) that was obtained from the plots of surface tension (γ) versus concentration showed that mixed surfactants have CMC values that were about 10 times lower than their single components. The large negative values for both interaction parameters suggest the existence of strong synergism between the oppositely charged surfactant molecules. The effect of hydrocarbon chain length of either surfactant was also compared and results showed that the effect of cationic surfactant chain length dominated that of the anionic surfactants. It was also discovered that certain mixed surfactant combinations behave differently from the expected trend.
Open reduction of proximal humerus fractures in the adolescent population
Authors: Pandya Nirav K. , Behrends Dominque , Hosalkar Harish S. 
Published: March 2012

Purpose Proximal humerus fractures in the pediatric population are a relatively uncommon injury, with the majority of injuries treated in a closed fashion due to the tremendous remodeling potential of the proximal humerus in the skeletally immature. Yet, in adolescent patients, open treatment is, at times, necessary due to unsatisfactory alignment following a closed reduction, loss of previously achieved closed reduction, and limited remodeling when close to skeletal maturity. The purpose of our study was to examine the open reduction of adolescent proximal humerus fractures. Methods A retrospective review of the outcomes of proximal humerus fractures in the adolescent population which were consecutively treated at our institution with open reduction was performed. Results Ten children met the inclusion criteria, with a mean age of 14.3 years (±1.3) and a mean weight of 60.7 kg (±14.9) at the time of injury. There were seven Salter-Harris 2 fractures and three Salter-Harris 1 fractures. The largest mean angulation was 55.0° (±33.9) and the largest mean displacement was 87.0 % (±22.8). Intra-operatively, impediments to closed reduction within the fracture site which were found included: periosteum (90.0 %), biceps tendon (90.0 %), deltoid muscle (70.0 %), and comminuted bone (10.0 %). K-wire fixation was most commonly used (70.0 %), followed by flexible nails (20.0 %) and cannulated screws (10.0 %) for fixation. All patients achieved radiographic union at a mean of 4.0 weeks (±0.7), had non-painful full shoulder range of motion and rotator cuff strength at final follow-up (mean 7.7 ± 4.6 months), and returned to pre-injury sporting activities. Conclusions The operative treatment of proximal humerus fracture, particularly in adolescents with severe displacement/angulation having failed closed methods of treatment, is increasingly considered to be an acceptable modality of treatment. In addition to the long head of the biceps, periosteum, deltoid muscle, and bone fragments in combination can prevent fracture reduction. Surgeon preference and skill should dictate implant choice, and the risk of physeal damage utilizing these implants in this age group is low.
The relation between bullying, victimization, and adolescents' level of hopelessness
Authors: Siyahhan Sinem , Aricak O. Tolga , Cayirdag‐Acar Nur 
Published: March 2012

ABSTRACTIn this study, 419 Turkish middle school students (203 girls, 216 boys) were surveyed on their exposure to and engagement in bullying, and their level of hopelessness. Our findings suggest that girls were victims of indirect (e.g. gossiping) bullying more than boys. Boys reported being victims of physical (e.g. damaging property) and verbal (e.g. teasing) bullying more than girls. While the level of hopelessness among victims of physical and verbal bullying was higher than non‐victims, no difference was found between the victims of indirect bullying and non‐victims. Students who never talked to their teachers and parents about bullying reported higher levels of hopelessness than others. The implications of the study for intervention and prevention programs are discussed.