bluuebunny/crossref_metadata_2025 huggingface dataset:
Transformation of a cadaver population: Analysis of a South African cadaver program, 1921–2013
Authors: Kramer Beverley , Hutchinson Erin F.
Published: December 2014

Anatomy has served as a cornerstone in the training of various allied and clinical disciplines and has traditionally been based on dissection of the human body. Thus, to pursue this method of teaching and learning, access to cadavers is of continuing importance. Over a significant period of time unclaimed cadavers have performed an essential role in the teaching of anatomy in South Africa and in Africa. As recent cadaver numbers were declining at the School of Anatomical Sciences, University of the Witwatersrand, Johannesburg and difficulty in procurement was being experienced, the purpose of this study was to critically evaluate the composition of our cadaver population over time so as to provide possible strategies to arrest the decline. A retrospective, quantitative analysis of cadaver records from the School of Anatomical Sciences between 1921 and 2013 was undertaken. Analysis included a comparison of Poisson counts and Fischer's exact test. A significant decrease in the number of cadavers received during the period 2000–2013 and a slow bequest program over the same period of time has led to concerns about the sustainability of teaching anatomy through dissection. Decreases in the numbers of males and cadavers of the black population group occurred between 1990 and 2013, and of bequests from 2000 to 2013. An influence on the cadaver population from a changing political climate and change in socioeconomic status of part of the population was perceived. Changes in sex and population group of the cadavers may have a long‐term effect on teaching and research. Anat Sci Educ 8: 445–451. © 2014 American Association of Anatomists.
Interprofessional education in anatomy: Learning together in medical and nursing training
Authors: Herrmann Gudrun , Woermann Ulrich , Schlegel Claudia
Published: December 2014

Teamwork and the interprofessional collaboration of all health professions are a guarantee of patient safety and highly qualified treatment in patient care. In the daily clinical routine, physicians and nurses must work together, but the education of the different health professions occurs separately in various places, mostly without interrelated contact. Such training abets mutual misunderstanding and cements professional protectionism, which is why interprofessional education can play an important role in dismantling such barriers to future cooperation. In this article, a pilot project in interprofessional education involving both medical and nursing students is presented, and the concept and the course of training are described in detail. The report illustrates how nursing topics and anatomy lectures can be combined for interprofessional learning in an early phase of training. Evaluation of the course showed that the students were highly satisfied with the collaborative training and believed interprofessional education (IPE) to be an important experience for their future profession and understanding of other health professionals. The results show that the IPE teaching concept, which combines anatomy and nursing topics, provides an optimal setting for learning together and helps nurses and doctors in training to gain knowledge about other health professionals' roles, thus evolving mutual understanding. Anat Sci Educ 8: 324–330. © 2014 American Association of Anatomists.
Preeminent visible‐light photocatalytic activity over BiOBr–BiVO4 heterojunctions
Authors: Cao F. P. , Ding C. H. , Liu K. C. , Kang B. Y. , Liu W. M.
Published: December 2014

The high recombination rate of photogenerated charges is the main problem that limits the photocatalytic activity of semiconductor photocatalysts. Herein, we have reported novel heterojunctions of BiOBr–BiVO4 fabricated by depositing BiOBr nanoflakes onto the surface of BiVO4. The optimum photocatalytic activity of the 0.925BiOBr–0.075BiVO4 heterojunction was almost 14 and 144 times as high as those of individual BiOBr and BiVO4 in visible‐light degradation of methylene blue. Photogenerated holes of BiVO4 would play a dominant role in the photocatalytic system.
Differences in electrophoretic behavior between linear and branched PEG‐conjugated proteins
Authors: Park Eun Ji , Sun Kim Myung , Suk Lee Hye , Choon Lee Kang , Hee Na Dong
Published: December 2014

The objective of this study was to characterize the differences in electrophoretic behavior between linear and branched PEG‐conjugated proteins. Human growth hormone and alpha‐lactalbumin modified by linear or branched PEGs with molecular weight of 10 kDa were analyzed by SEC, MALDI‐TOF MS, SDS‐PAGE, and microchip CGE (MCGE). Chromatographic and mass spectrometric differences between the linear and branched PEG‐proteins on SEC and MALDI‐TOF MS were small, but their electrophoretic behaviors on SDS‐PAGE and MCGE were significantly different. In particular, MCGE showed significant differences in the peak width and the migration times of linear and branched PEG‐proteins, in which the branched PEG‐proteins exhibited a narrower peak and longer migration time than the linear PEG‐proteins. This phenomenon may explain the longer circulation half‐life for the branched PEG‐proteins observed in previously reported in vivo studies. Consequently, this study indicates that MCGE may be a valuable tool for differentiating linear and branched PEG‐proteins.
2015 Exploration Rover Challenge registration open
Authors: Sullivan Kelly J.
Published: December 2014

High school, college and university students may now register for the National Aeronautics and Space Administration's (NASA) 2015 Human Exploration Rover Challenge taking place April 16–18, 2015, at the U.S. Space & Rocket Center in Huntsville, Ala.
Impact of apurinic/apyrimidinic endonuclease 1/redox factor‐1 on treatment response and survival in oral squamous cell carcinoma
Authors: Hsia Kan‐Tai , Liu Chung‐Ji , Mar Kwei , Lin Li‐Han , Lin Chun‐Shu , Cheng Ming‐Fang , Lee Herng‐Sheng , Chiu Shang‐Yi
Published: December 2014

Background

Apurinic/apyrimidinic endonuclease 1/redox factor‐1 (APE1/Ref‐1) is a multifunctional protein involved in DNA repair and redox signaling. The purpose of this study was to investigate the relationship between APE1/Ref‐1 expression and clinicopathological features, survival, and treatment response in patients with oral squamous cell carcinoma (OSCC) and cell lines.

Methods

APE1/Ref‐1 expression in OSCC was evaluated by immunohistochemistry, and its relationship to patient outcomes and treatment response was assessed statistically. The effects of stable short hairpin (sh)RNA‐mediated knockdown of APE1/Ref‐1 on cell survival, migration, and chemoradiation sensitivity were determined in OSCC cell lines.

Results

APE1/Ref‐1 immunostaining was correlated with positive lymph node status, and higher APE1/Ref‐1 expression was significantly associated with poor prognosis and reduced treatment response. Consistent with the clinical studies, APE1/Ref‐1 expression in OSCC cell lines was implicated in the regulation of migration and cisplatin‐induced apoptosis.

Conclusion

Elevated APE1/Ref‐1 expression may be used to predict poor survival and may confer chemoresistance in OSCC. © 2015 Wiley Periodicals, Inc. Head Neck 38: 550–559, 2016
Decomposing Complete Equipartite Multigraphs into Cycles of Variable Lengths: The Amalgamation‐detachment Approach
Authors: Bahmanian M. Amin , Šajna Mateja
Published: December 2014

Using the technique of amalgamation‐detachment, we show that the complete equipartite multigraph can be decomposed into cycles of lengths (plus a 1‐factor if the degree is odd) whenever there exists a decomposition of into cycles of lengths (plus a 1‐factor if the degree is odd). In addition, we give sufficient conditions for the existence of some other, related cycle decompositions of the complete equipartite multigraph .
Profiling of grape monoterpene glycosides (aroma precursors) by ultra‐high performance‐liquid chromatography‐high resolution mass spectrometry (UHPLC/QTOF)
Authors: Flamini Riccardo , De Rosso Mirko , Panighel Annarita , Dalla Vedova Antonio , De Marchi Fabiola , Bavaresco Luigi
Published: December 2014

A ‘suspect screening analysis’ method for grape metabolomics by ultra‐high performance‐liquid chromatography (UHPLC) and high‐resolution quadrupole‐time of flight (QTOF) mass spectrometry was recently developed. This method was applied to study grape monoterpene glycosides, the main grape aroma precursors. Since standard compounds were not available, they were tentatively identified by overlapping various analytical approaches, in agreement with the indications recommended in mass spectrometry (MS)‐based metabolomics. Accurate mass and isotopic pattern, MS/MS fragmentation, correlation between fragments observed and putative structures and between liquid chromatography coupled with mass spectrometry (LC/MS) and gas chromatography/mass spectrometry signals were studied. Seventeen monoterpene glycosides were identified without performing the hydrolytic artifacts commonly used to study these compounds which may affect sample profile. This is the first time that a detailed study of these aroma precursors has been carried out by direct LC/MS analysis. Copyright © 2014 John Wiley & Sons, Ltd.
Membrane introduction mass spectrometry (MIMS): a versatile tool for direct, real‐time chemical measurements
Authors: Krogh Erik T. , Gill Chris G.
Published: December 2014

Membrane introduction mass spectrometry (MIMS) is a direct, continuous, on‐line measurement technique. It utilizes a membrane to semi‐selectively transfer analyte mixtures from a sample to a mass spectrometer, rejecting the bulk of the sample matrix, which can be a gas, liquid or solid/slurry. Analyte selectivity and sensitivity are affected by optimizations at the membrane, ionization and the mass spectrometer levels. MIMS can be roughly classified by the acceptor phase that entrains analyte(s) to the mass spectrometer after membrane transport, either a gaseous acceptor phase (GP‐MIMS) or condensed acceptor phase (CP‐MIMS). The aim of this article is to provide an introduction to MIMS as a technique and to explore current variants, recent developments and modern applications, emphasizing examples from our group, the Applied Environmental Research Laboratories as well as selected work from others in this emerging area. Also provided is a synopsis of current and future directions for this versatile analytical technique. Copyright © 2014 John Wiley & Sons, Ltd.
Direct targeted glycation of the free sulfhydryl group of cysteine residue (Cys‐34) of BSA. Mapping of the glycation sites of the anti‐tumor Thomsen–Friedenreich neoglycoconjugate vaccine prepared by Michael addition reaction
Authors: Demian Wael L. L. , Kottari Naresh , Shiao Tze Chieh , Randell Edward , Roy René , Banoub Joseph H.
Published: December 2014

We present in this manuscript the characterization of the exact glycation sites of the Thomsen–Friedenreich antigen–BSA vaccine (TF antigen:BSA) prepared using a Michael addition reaction between the saccharide antigen as an electrophilic acceptor and the nucleophilic thiol and L‐Lysine ε‐amino groups of BSA using different ligation conditions. Matrix laser desorption ionization time‐of‐flight mass spectrometry of the neoglycoconjugates prepared with TF antigen:protein ratios of 2:1 and 8:1, allowed to observe, respectively, the protonated molecules for each neoglycoconjugates: [M + H]+ at m/z 67 599 and 70 905. The measurements of these molecular weights allowed us to confirm exactly the carbohydrate:protein ratios of these two synthetic vaccines. These were found to be closely formed by a TF antigen:BSA ratios of 2:1 and 8:1, respectively. Trypsin digestion and liquid chromatography coupled with electrospray ionization mass spectrometry allowed us to identify the series of released glycopeptide and peptide fragments. De novo sequencing affected by low‐energy collision dissociation tandem mass spectrometry was then employed to unravel the precise glycation sites of these neoglycoconjugate vaccines. Finally, we identified, respectively, three diagnostic and characteristic glycated peptides for the synthetic glycoconjugate possessing a TF antigen:BSA ratio 2:1, whereas we have identified for the synthetic glycoconjugate having a TF:BSA ratio 8:1 a series of 14 glycated peptides. The net increase in the occupancy sites of these neoglycoconjugates was caused by the large number of glycoforms produced during the chemical ligation of the synthetic carbohydrate antigen onto the protein carrier. Copyright © 2014 John Wiley & Sons, Ltd.
Optimized precursor ion selection for labile ions in a linear ion trap mass spectrometer and its impact on quantification using selected reaction monitoring
Authors: Lee Hyun‐Seok , Shin Kyong‐Oh , Jo Sung‐Chan , Lee Yong‐Moon , Yim Yong‐Hyeon
Published: December 2014

The fragmentation of fragile ions during the application of an isolation waveform for precursor ion selection and the resulting loss of isolated ion intensity is well‐known in ion trap mass spectrometry (ITMS). To obtain adequate ion intensity in the selected reaction monitoring (SRM) of fragile precursor ions, a wider ion isolation width is required. However, the increased isolation width significantly diminishes the selectivity of the channels chosen for SRM, which is a serious problem for samples with complex matrices. The sensitive and selective quantification of many lipid molecules, including ceramides from real biological samples, using a linear ion trap mass spectrometer is also hindered by the same problem because of the ease of water loss from protonated ceramide ions. In this study, a method for the reliable quantification of ceramides using SRM with near unity precursor ion isolation has been developed for ITMS by utilizing alternative precursor ions generated by in‐source dissociation. The selected precursor ions allow the isolation of ions with unit mass width and the selective analysis of ceramides using SRM with negligible loss of sensitivity. The quantification of C18:0‐, C24:0‐ and C24:1‐ceramides using the present method shows excellent linearity over the concentration ranges from 6 to 100, 25 to 1000 and 25 to 1000 nM, respectively. The limits of detection of C18:0‐, C24:0‐ and C24:1‐ceramides were 0.25, 0.25 and 5 fmol, respectively. The developed method was successfully applied to quantify ceramides in fetal bovine serum. Copyright © 2014 John Wiley & Sons, Ltd.
Ultra‐high performance liquid chromatography tandem mass spectrometry for the detection of durum wheat contamination or adulteration
Authors: Russo Rosita , Cusano Erica , Perissi Andrea , Ferron Francisco , Severino Valeria , Parente Augusto , Chambery Angela
Published: December 2014

In this work, an ultra‐performance liquid chromatography electrospray ionization (UPLC‐ESI)‐MS/MS methodology based on multiple reaction monitoring (MRM) for the selective and sensitive detection and quantification of durum wheat adulteration has been developed and fully validated. The targeted analysis was performed by monitoring specific transitions at m/z 543.7 > 657.4 and m/z 543.7 > 299.2 of a species‐specific marker derived from a tryptic peptide of puroindoline a (Pin‐a), a cysteine‐rich protein selectively present only in common wheat. In addition, two transitions at m/z 500.4 > 725.4 and m/z 500.4 > 561.9 of a reference peptide belonging to purothionin A‐1, present in both species, were also monitored. The calibration curves obtained on binary mixtures with known percentages of common/durum wheat flours showed linearity (coefficient of regression, r ≥ 0.99) over concentrations that ranged between 80 and 1%. The limit of detection (LOD) and limit of quantification (LOQ) for the Pin‐a marker in wheat flours were 0.01 and 0.03%, respectively. The identified Pin‐a marker was also found to be highly diagnostic for the quantification of common wheat in raw materials (kernels) and processed products (pasta), thus offering new opportunities to assess food authenticity. Copyright © 2014 John Wiley & Sons, Ltd.
Addition–elimination versus Tishchenko reaction in the gas phase
Authors: Wilenska Beata , Swider Pawel , Danikiewicz Witold
Published: December 2014

Gas phase reactions of the substituted phenide ions with methyl formate have been studied. It was found that the results of these reactions depend mainly on the basicity of the phenide ion, which is related to the presence of the electron‐accepting or electron‐donating substituents in the benzene ring. It was shown that the phenide ions substituted with electron‐withdrawing groups react with methyl formate in the gas phase in a two‐step reaction. The first step that proceeds according to the typical addition–elimination mechanism results in the formation of the anion of the respective benzaldehyde derivative with the negative charge located either in the aldehyde group (acyl anion) or in the benzene ring (phenide anion) in position ortho to an aldehyde moiety. In the second step, the preliminary‐formed anion reacts with the second molecule of methyl formate yielding formally product of the second addition–elimination reaction. Theoretical calculations as well as collision induced dissociation spectra of the model compounds suggest that this reaction proceeds according to the Tishchenko reaction mechanism yielding the respective phthalide anion. According to our knowledge, this is the first example of the Tishchenko‐type reaction in the gas phase. Copyright © 2014 John Wiley & Sons, Ltd.
Orbitrap™ monostage MS versus hybrid linear ion trap MS: application to multi‐allergen screening in wine
Authors: Pilolli Rosa , De Angelis Elisabetta , Godula Michal , Visconti Angelo , Monaci Linda
Published: December 2014

Food allergen research has made giant steps in the last years thanks to the features offered by the latest technology of mass analyzers placed on the market allowing multiplex sensitive detection of proteins. Potentials and features of two mass analyzers namely a linear ion trap capable of performing a data dependent or selected reaction monitoring analysis and an OrbitrapTM stand‐alone MS enabling a broadband fragmentation without mass selection at highest mass resolving power are herein described and applied to the multiplex screening of allergens in a type of wine chosen as a reference matrix. Quantitative and confirmative capabilities of both platforms were assessed on the specific case study, the multiple detection of egg and milk ‐related proteins, typically employed in white wines as fining agents. Commercial bioinformatic tools used for a quick allergen identification will be also discussed. Copyright © 2014 John Wiley & Sons, Ltd.
Preparing to read the ubiquitin code: a middle‐out strategy for characterization of all lysine‐linked diubiquitins
Authors: Lee Amanda E. , Castañeda Carlos A. , Wang Yan , Fushman David , Fenselau Catherine
Published: December 2014

Multiple studies demonstrate that ubiquitination of proteins codes for regulation of cell differentiation, apoptosis, endocytosis and many other cellular functions. There is great interest in and considerable effort being given to defining the relationships between the structures of polyubiquitin modifications and the fates of the modified proteins. Does each ubiquitin modification achieve a specific effect, much like phosphorylation, or is ubiquitin like glycosylation, where there is heterogeneity and redundancy in the signal? The sensitive analytical tools needed to address such questions readily are not yet mature. To lay the foundation for mass spectrometry (MS)‐based studies of the ubiquitin code, we have assembled seven isomeric diubiquitins with all‐native sequences and isopeptide linkages. Using these compounds as standards enables the development and testing of a new MS‐based strategy tailored specifically to characterize the number and sites of isopeptide linkages in polyubiquitin chains. Here, we report the use of Asp‐selective acid cleavage, separation by reverse phase high‐performance liquid chromatography and characterization by tandem MS to distinguish and characterize all seven isomeric lysine‐linked ubiquitin dimers. Copyright © 2014 John Wiley & Sons, Ltd.
Specific rearrangement reactions of acetylated lysine containing peptide bn (n = 4–7) ion series
Authors: Atik A. Emin , Hernandez Oscar , Maître Philippe , Yalcin Talat
Published: December 2014

Characterization of ε‐N‐acetylated lysine containing peptides, one of the most prominent post‐translational modifications of proteins, is an important goal for tandem mass spectrometry experiments. A systematic study for the fragmentation reactions of b ions derived from ε‐N‐acetyllysine containing model octapeptides (KAcYAGFLVG and YAKAcGFLVG) has been examined in detail. Collision‐induced dissociation (CID) mass spectra of bn (n = 4–7) fragments of ε‐N‐acetylated lysine containing peptides are compared with those of N‐terminal acetylated and doubly acetylated (both ε‐N and N‐terminal) peptides, as well as acetyl‐free peptides. Both direct and nondirect fragments are observed for acetyl‐free and singly acetylated (ε‐N or N‐terminal) peptides. In the case of ε‐N‐acetylated lysine containing peptides, however, specific fragment ions (m/z 309, 456, 569 and 668) are observed in CID mass spectra of bn (n = 4–7) ions. The CID mass spectra of these four ions are shown to be identical to those of selected protonated C‐terminal amidated peptides. On this basis, a new type of rearrangement chemistry is proposed to account for the formation of these fragment ions, which are specific for ε‐N‐acetylated lysine containing peptides. Consistent with the observation of nondirect fragments, it is proposed that the b ions undergo head‐to‐tail macrocyclization followed by ring opening. The proposed reaction pathway assumes that bn (n = 4–7) of ε‐N‐acetylated lysine containing peptides has a tendency to place the KAc residue at the C‐terminal position after macrocyclization/reopening mechanism. Then, following the loss of CO, it is proposed that the marker ions are the result of the loss of an acetyllysine imine as a neutral fragment. Copyright © 2014 John Wiley & Sons, Ltd.
Measuring oxygen yields of a thermal conversion/elemental analyzer‐isotope ratio mass spectrometer for organic and inorganic materials through injection of CO
Authors: Yin Xijie , Chen Zhigang
Published: December 2014

The thermal conversion/elemental analyzer‐isotope ratio mass spectrometer (TC/EA‐IRMS) is widely used to measure the δ18O value of various substances. A premise for accurate δ18O measurement is that the oxygen in the sample can be converted into carbon monoxide (CO) quantitatively or at least proportionally. Therefore, a precise method to determine the oxygen yield of TC/EA‐IRMS measurements is needed. Most studies have used the CO peak area obtained from a known amount of a solid reference material (for example, benzoic acid) to calibrate the oxygen yield of the sample. Although it was assumed that the oxygen yield of the solid reference material is 100%, no direct evidence has been provided. As CO is the analyte gas for δ18O measurement by IRMS, in this study, we use a six‐port valve to inject CO gas into the TC/EA. The CO is carried to the IRMS by the He carrier gas and the CO peak area is measured by the IRMS. The CO peak area thus obtained from a known amount of the injected CO is used to calibrate the oxygen yield of the sample. The oxygen yields of commonly used organic and inorganic reference materials such as benzoic acid (C6H5COOH), silver phosphate (Ag3PO4), calcium carbonate (CaCO3) and silicon dioxide (SiO2) are investigated at different reactor temperatures and sample sizes. We obtained excellent linear correlation between the peak area for the injected CO and its oxygen atom amount. C6H5COOH has the highest oxygen yield, followed by Ag3PO4, CaCO3 and SiO2. The oxygen yields of TC/EA‐IRMS are less than 100% for both organic and inorganic substances, but the yields are relatively stable at the specified reactor temperature and for a given quantity of sample. Copyright © 2014 John Wiley & Sons, Ltd.
Determination of drugs of abuse in bovine dentin using liquid chromatography–electrospray ionization tandem mass spectrometry
Authors: Spinner J. , Klima M. , Kempf J. , Huppertz L. M. , Auwärter V. , Altenburger M. J. , Neukamm M. A.
Published: December 2014

Drugs deposited in human teeth are well preserved; the spectrum of toxicological investigations may therefore be supplemented by an analysis method for drugs in teeth. A liquid chromatography–electrospray ionization tandem mass spectrometry assay for the detection and quantification of basic drugs of abuse in bovine dentin samples was developed and validated. The drugs and metabolites amphetamine, methamphetamine, methylenedioxymethylamphetamine, methylenedioxyethylamphetamine, codeine, morphine, cocaine and benzoylecgonine were extracted from 50 mg ground dentin powder by ultrasonication for 60 min in methanol 3 times. The extracts were analyzed on a triple‐quadrupole mass‐spectrometer in multiple reaction monitoring mode. The method was validated and proved to be accurate, precise, selective, specific and stable with good linearity within the calibration range and a lower limit of quantification of 10 to 20 pg/mg. To artificially load bovine dentin samples with drugs, the natural process of de‐ and remineralization in the oral cavity was mimicked by a pH‐cycling experiment. The artificially drug‐loaded dentin samples showed drug concentrations of 20 to 80 pg/mg. The method can be applied in further in vitro experiments as well as in post‐mortem cases, especially where limited sample tissue is available. Copyright © 2014 John Wiley & Sons, Ltd.
Examination of small molecule losses in 5‐methylpyranopelargonidin MS/MS CID spectra by DFT calculations
Authors: Kurka Ondřej , Roithová Jana , Bednář Petr
Published: December 2014

Pyranoanthocyanins are formed during food treatment and maturation (e.g. wine, juices), and they can be considered a natural alternative to artificial food colorants. Tandem mass spectrometry (MS/MS) is perhaps the most important technique in analysis of anthocyanin dyes. Knowledge of fragmentation pattern is a key aspect of their successful structural characterization. Polyphenolic compounds are known to lose small molecules during collision‐induced dissociation (CID) in MS/MS experiments. However, the specific positions where such losses occur preferentially are unknown. The aim of this communication is to investigate the energetically most preferred places for H2O and CO losses during the fragmentation of 5‐methylpyranopelargonidin molecule by the means of computational chemistry (employing density functional theory) combined with CID MS/MS experiments and infrared multiphoton dissociation spectroscopy. Mechanisms responsible for the fragmentations were investigated, and optimal geometries and transition states were obtained. Cleavage of water as well as carbon monoxide occurs preferentially from the C‐ring of flavonoid skeleton. In the most stable structure of 5‐methylpyranopelargonidin, B‐ring was found to be tilted with respect to the rest of the molecule. Planarization effort of the parent molecule contributes both to its decarbonylation and dehydration. Copyright © 2014 John Wiley & Sons, Ltd.
Molecular formula analysis of fragment ions by isotope‐selective collision‐induced dissociation tandem mass spectrometry of pharmacologically active compounds
Authors: Bianco Giuliana , Buchicchio Alessandro , Lelario Filomena , Cataldi Tommaso R.I.
Published: December 2014

The purpose of this work is to explore the mass fragment characterization of commonly used drugs through a novel approach, which involves isotope‐selective tandem mass spectrometry (MS/MS). Collision‐induced dissociation (CID) was performed with a low‐resolution linear ion trap mass spectrometer in positive electrospray ionization. Three pharmacologically active ingredients, i.e. omeprazole, meloxicam and brinzolamide, selected as model compounds in their own formulation, were investigated as a sodiated adduct [C17H19N3O3S + Na]+ (omeprazole) and as protonated adducts, [C14H13N3O4S2 + H]+ and [C12H21N3O5S3 + H]+, meloxicam and brinzolamide, respectively. Selecting a narrow window of ±0.5 m/z units, precursor ion fragmentation by CID‐MS/MS of isotopologues A + 0, A + 1 and A + 2 was found very useful to confirm the chemical formula of product ions, thus aiding the establishment of characteristic fragmentation pathways of all three examined compounds. The correctness of putative molecular formula of product ions was easily demonstrated by exploiting the isotope peak abundance ratios (i.e. IF+0/IF+1 and IF+0/IF+2) as simple constraints in low‐resolution MS instrumentations. Copyright © 2014 John Wiley & Sons, Ltd.
Differentiation of isomeric dinitrotoluenes and aminodinitrotoluenes using electrospray high resolution mass spectrometry
Authors: Schwarzenberg Adrián , Dossmann Héloïse , Cole Richard B. , Machuron‐Mandard Xavier , Tabet Jean‐Claude
Published: December 2014

Explosive detection and identification play an important role in the environmental and forensic sciences. However, accurate identification of isomeric compounds remains a challenging task for current analytical methods. The combination of electrospray multistage mass spectrometry (ESI‐MSn) and high resolution mass spectrometry (HRMS) is a powerful tool for the structure characterization of isomeric compounds. We show herein that resonant ion activation performed in a linear quadrupole ion trap allows the differentiation of dinitrotoluene isomers as well as aminodinitrotoluene isomers. The explosive‐related compounds: 2,4‐dinitrotoluene (2,4‐DNT), 2,6‐dinitrotoluene (2,6‐DNT), 2‐amino‐4,6‐dinitrotoluene (2A‐4,6‐DNT) and 4‐amino‐2,6‐dinitrotoluene (4A‐2,6‐DNT) were analyzed by ESI‐MS in the negative ion mode; they produced mainly deprotonated molecules [M − H]−. Subsequent low resolution MSn experiments provided support for fragment ion assignments and determination of consecutive dissociation pathways. Resonant activation of deprotonated dinitrotoluene isomers gave different fragment ions according to the position of the nitro and amino groups on the toluene backbone. Fragment ion identification was bolstered by accurate mass measurements performed using Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR/MS). Notably, unexpected results were found from accurate mass measurements performed at high resolution for 2,6‐DNT where a 30‐Da loss was observed that corresponds to CH2O departure instead of the expected isobaric NO• loss. Moreover, 2,4‐DNT showed a diagnostic fragment ion at m/z 116, allowing the unambiguous distinction between 2,4‐ and 2,6‐DNT isomers. Here, CH2O loss is hindered by the presence of an amino group in both 2A‐4,6‐DNT and 4A‐2,6‐DNT isomers, but nevertheless, these isomers showed significant differences in their fragmentation sequences, thus allowing their differentiation. DFT calculations were also performed to support experimental observations. Copyright © 2014 John Wiley & Sons, Ltd.
CPAS: Surgical approach with combined sublabial bone resection and inferior turbinate reduction without stents
Authors: Merea Valeria S. , Lee Andrew H. Y. , Peron Didier L. , Waldman Erik H. , Grunstein Eli
Published: December 2014

Objectives/Hypothesis

Congenital pyriform aperture stenosis (CPAS) is a form of nasal obstruction caused by congenital narrowing of the maxilla at the medial processes. Traditionally, surgical correction involves a sublabial approach with subperiosteal dissection, widening of the aperture by drilling, and the use of nasal stents postoperatively. Although this approach may lead to symptomatic improvement, it alone may fail to provide a patent airway secondary to unaddressed posterior narrowing. Additionally, the use of stents is problematic because they are prone to clogging and can cause internal nasal scarring and septal or alar necrosis. We present the surgical management of this condition in six patients using a novel approach that aims to correct these limitations by including both the traditional sublabial procedure and an endonasal reduction of the inferior turbinates, without the use of stents postoperatively.

Study Design

Retrospective chart review.

Methods

Review of the medical records of six consecutive patients aged 2 weeks to 7 months, who underwent repair of CPAS via a sublabial ostectomy and endonasal inferior turbinate reduction from 2009 to 2012.

Results

All six patients were clear of airway obstruction postoperatively and at follow‐up.

Conclusion

This is an alternative approach that leads to symptomatic improvement for CPAS patients without the morbidity associated with stent use.

Level of Evidence

4. Laryngoscope, 125:1460–1464, 2015
The utility of office‐based biopsy for laryngopharyngeal lesions: Comparison with surgical evaluation
Authors: Richards Amanda L. , Sugumaran Manikandan , Aviv Jonathan E. , Woo Peak , Altman Kenneth W.
Published: December 2014

Objectives/Hypothesis

Advances in flexible endoscopy with working‐channel biopsy forceps have led to excellent visualization of laryngopharyngeal lesions with capability for in‐office awake biopsy. Potential benefits include prompt diagnosis without risk of general anesthesia, preoperative counseling, and avoiding an anesthetic should the lesion return benign. We evaluate the accuracy of these biopsies in order to determine their role and diagnostic value.

Study Design

Retrospective chart review.

Methods

Medical records were reviewed from January 1, 2010, through July 31, 2013, of patients who underwent office‐based current procedural terminology code 31576 and were taken to the operating room for direct microlaryngoscopy with biopsy/excision. Clinical diagnoses and pathology reports were reviewed. For statistical analysis, we considered three groups: 1) malignant and premalignant, 2) lesions of uncertain significance, and 3) benign lesions.

Results

In the study period, 76 patients with an office biopsy had a clinical picture to warrant direct microlaryngoscopy and biopsy/excision. Kendall's coefficient for each group indicated moderate correlation only. When groups 1 and 2 were considered together, there was a substantial and statistically significant correlation. For malignant and premalignant lesions, the office biopsy analysis was as follows: sensitivity = 60%, specificity = 87%, positive predictive value = 78%, and negative predictive value = 74%.

Conclusion

Office biopsy may offer early direction and avoid operative intervention in some cases; however, for suspected dysplastic or malignant lesions, direct microlaryngoscopy should be the standard of care to ensure adequate full‐thickness sampling and staging. For benign pathology, office biopsy is a safe and viable alternative to direct microlaryngoscopy and biopsy/excision.

Level of Evidence

4. Laryngoscope, 125:909–912, 2015
Skin problems following septorhinoplasty
Authors: Koc Eltaf A. O. , Buyuklu Fuat , Koç Bulent , Demirci Gulsen T.
Published: December 2014

Objectives/Hypothesis

Septorhinoplasty is one of the most commonly performed plastic surgery procedures in the world. Studies on septorhinoplasty in the literature mainly focus on the surgical procedures and their outcomes, but the general appearance of the nose and nasal skin following surgery is also very important.

Study Design

Case‐control study examining 30 septorhinoplasty patients and 20 septoplasty patients for postoperative skin conditions.

Results

There were significant differences identified between the septorhinoplasty group and the septoplasty group with respect to their mean preoperative Global Acne Grading System, Seborrheic Dermatitis Area Severity Index, and visual analog scores (acne, seborrhea, and ecchymosis).

Conclusions

The aim of study was to identify and evaluate postoperative skin conditions among septorhinoplasty patients, as well as the progression and duration of treatment of these conditions.

Level of Evidence

3b Laryngoscope, 125:1291–1295, 2015
Successful treatment of sudden sensorineural hearing loss assures improvement of accompanying tinnitus
Authors: Rah Yoon C. , Park Kyung T. , Yi Yeo‐Jeen , Seok Jungirl , Kang Seong I. , Kim Young H.
Published: December 2014

Objectives/Hypothesis

To investigate the long‐term outcomes of accompanying tinnitus after steroid therapy for patients with sudden sensorineural hearing loss (SSNHL).

Study Design

Retrospective chart review and survey.

Methods

Fifty patients diagnosed with SSNHL accompanied by tinnitus were enrolled and divided into two groups—satisfied and unsatisfied—according to the degree of improvement of tinnitus after SSNHL treatment. Subjective improvement of tinnitus and hearing status were investigated before and 6 months after SSNHL treatment. Hearing improvement was assessed using criteria from our previous study and Siegel's criteria. The change of tinnitus was assessed using a visual analogue scale for tinnitus intensity and frequency.

Results

Patients with more severe initial hearing loss had less chance of hearing recovery (P = .05). The satisfied group included significantly more cases with better hearing recovery after SSNHL treatment than the unsatisfied group (P = .049). Pure‐tone threshold and speech discrimination scores were significantly better in the satisfied group than in the unsatisfied group after SSNHL treatment (P = .033 and P = .018, respectively), although the two groups showed no definitive differences before treatment.

Conclusions

Optimal and successful treatment of SSNHL may be an important factor in obtaining favorable long‐term control of tinnitus accompanied by SSNHL.

Level of Evidence

4. Laryngoscope, 125:1433–1437, 2015
Gap junction enhances phototoxicity of photodynamic therapy agent 2‐[1‐hexyloxyethyl]‐2‐devinylpyropheophorbide‐a (HPPH)
Authors: Liu Zhen , Wang Qin , Fan Lixia , Wu Deng Pan , Zhang Yuan , Liu Lucy , Tao Liang
Published: December 2014

Background and Objective

It has been reported that 2‐(1‐hexyloxyethyl)‐2‐devinyl pyropheophorbide‐a (HPPH)‐mediated photodynamic therapy (PDT) effects on antitumor. However, it remains unclear whether gap junction (GJ) acts on phototoxicity of HPPH and which pathways are involved in the process.

Materials and Methods

We determine the effect of HPPH on cancer cell viability and the apoptosis‐associated signaling by cell viability assay, reactive oxygen species (ROS) measurement, and caspase‐3 activity assay.

Results

Our study uniquely showed that there is a strong correlation between GJ and HPPH‐PDT cytotoxicity, that inhibition of GJ function in U87 cells by tetradecanoylphorbol‐13‐aaetate or carbenoxolone reduces HPPH‐PDT cytotoxicity, that and the enhancement of GJ function by retinoid acid in U87 cells increases HPPH‐PDT cytotoxicity. We also observed that GJ intercellular communication composed of connexin 32 (Cx32) induced by doxycycline in Hela cells enhances HPPH‐PDT phototoxicity. In addition, we indicated that GJ prompts the HPPH‐induced apoptosis likely due to the “bystander effect” of passing apoptotic signals between cells, which results in improving the accumulation of ROS, which also amplifies mitochondria depolarization and the activation of caspase‐3.

Conclusion

GJ enhances the efficacy of HPPH‐PDT in U87 and Hela; GJ augments ROS production, which enhances the loss of mitochondrial membrane potential and the activation of caspase‐3, and increases apoptosis in the tumor cells induced by HPPH‐PDT. Our findings provide a basis for further development of GJ as a potential prediction of the efficacy of photodynamic therapy. Lasers Surg. Med. 47:68–76, 2015. © 2014 Wiley Periodicals, Inc.
Recent Advances in Nanoscale Bioinspired Materials
Authors: Demirel Melik C. , Cetinkaya Murat , Pena‐Francesch Abdon , Jung Huihun
Published: December 2014

Natural materials have been a fundamental part of human life since the dawn of civilization. However, due to exploitation of natural resources and cost issues, synthetic materials replaced bio‐derived materials in the last century. Recent advances in bio‐ and nano‐technologies pave the way for developing eco‐friendly materials that could be produced easily from renewable resources at reduced cost and in a broad array of useful applications. This feature article highlights structural and functional characteristics of bio‐derived materials, which will expedite the design fabrication and synthesis of eco‐friendly and recyclable advanced nano‐materials and devices.
Synthetic Control of Pore Properties in Conjugated Microporous Polymers Based on Carbazole Building Blocks
Authors: Wang Xiaoyan , Zhao Yang , Wei Lingling , Zhang Chong , Yang Xiao , Yu Miao , Jiang Jia‐Xing
Published: December 2014

A series of conjugated microporous polymers (CMPs) from 1,3,6,8‐tetrabromocarbazole and its alkylated derivative is synthesized via Suzuki cross‐coupling polycondensation. These polymer networks are stable in common organic solvents and thermally stable. The pore properties (pore size and surface area) of this kind of CMPs can be tuned by using either a linker with different geometries or carbazole substituted with alkyl groups. All of the polymers show high isosteric heats of CO2 adsorption (27.1–30.8 kJ mol−1) because the incorporation of nitrogen atoms into the skeleton of the CMP enhances the interaction between the pore wall and CO2 molecules. The polymer PPTBC shows a high Brunauer–Emmett–Teller specific surface area up to 917 m2 g−1 with a high CO2 uptake ability of 2.93 mmol g−1 at 1.13 bar/273 K. These data show that these materials are potential candidates for applications in post‐combustion CO2 capture and sequestration technology.

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Dendritic Polyurea Polymers
Authors: Tuerp David , Bruchmann Bernd
Published: December 2014

Dendritic polymers, subsuming dendrimers as well as hyperbranched or highly branched polymers are well established in the field of polymer chemistry. This review article focuses on urea based dendritic polymers and summarizes their synthetic routes through both isocyanate and isocyanate‐free processes. Furthermore, this article highlights applications where dendritic polyureas show their specific chemical and physical potential. For these purposes scientific publications as well as patent literature are investigated to generate a comprehensive overview on this topic.

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Tuning the LCST and UCST Thermoresponsive Behavior of Poly(N,N‐dimethylaminoethyl methacrylate) by Electrostatic Interactions with Trivalent Metal Hexacyano Anions and Copolymerization
Authors: Zhang Qilu , Tosi Filippo , Üǧdüler Sibel , Maji Samarendra , Hoogenboom Richard
Published: December 2014

Poly(N,N‐dimethylaminoethyl methacrylate) (PDMAEMA) has been reported to show both upper critical solution temperature (UCST) and lower critical solution temperature (LCST) behavior in presence of trivalent metal hexacyano anions, which is attractive for the development of smart materials. In this communication, the influence of the double thermoresponsive behavior of PDMAEMA driven by electrostatic interactions is investigated by comparing systems with [Co(CN)6]3−, [Fe(CN)6]3−, and [Cr(CN)6]3− as trivalent anions. Furthermore, tuning of double thermoresponsive behavior of PDMAEMA by incorporating hydrophilic or hydrophobic comonomers is also discussed in the presence of [Fe(CN)6]3− as trivalent ion.

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Scope and Limitations of a Direct Arylation Polycondensation Scheme in the Synthesis of PCPDTBT‐Type Copolymers
Authors: Kowalski Sebastian , Allard Sybille , Scherf Ullrich
Published: December 2014

Direct arylation polycondensation represents a promising alternative to the currently used aryl–aryl coupling schemes for conjugated polymer synthesis that is characterized by a potentially lower impact on the environment and reduced costs. However, scope and limitations of this novel protocol are not fully understood until now. Two main aspects are, hereby, i) the chemical nature of side reactions that occur during coupling of nonactivated and dihalogenated aromatic monomers, and ii) the influence of steric and electronic factors on the reactivity of the monomers. Within this communication, the 4,4‐bis(2‐ethylhexyl)‐cyclopenta[1,2‐b:5,4‐b′]dithiophene (CPDT)/2,1,3‐benzothiadiazole (BT) monomer couple for direct arylation synthesis of the alternating copolymer poly(4,4‐(2‐ethylhexyl)‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐alt‐2,1,3‐benzothiadiazole) (PCPDTBT) is studied and homocoupling identified as the dominating side reaction. The study demonstrates that homocoupling can be almost completely suppressed through a clever choice of the reaction conditions. Finally, the findings implicate that mainly electronic factors control the reactivity of both monomers.

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Strength and failure behaviour of carbon fibre reinforced plastics (CFRP)‐aluminium seam structures
Authors: Schumacher J. , Clausen B. , Zoch H.‐W.
Published: December 2014

In modern lightweight structures different requirements for components occur. In many cases they cannot be fulfilled by a single material in an optimum way. Therefore, the use of different materials with different properties is desirable. The combination of CFRP (carbon fibre reinforced plastics) and aluminium alloys is promising for structural components with regard to lightweight design. The materials are joined conventionally by riveting or adhesive bonding. However, these joining methods lead to a weakened region in the load path and a bulky design. The researcher group “Schwarz‐Silber” (FOR 1224), founded by the DFG (German Research‐Foundation), investigates new interface structures for advanced carbon fibre reinforced plastics‐aluminium compounds in five interdisciplinary projects. This paper deals with the strength and the failure behaviour of three differently manufactured carbon fibre reinforced plastics‐aluminium seam structures under tensile loading. Due to the contact of the seam structures to the carbon fibre reinforced plastics as well as to the aluminium part each connection consists of two joining areas which may act as the weak point of the connection.
Characteristics and Origin of Rock Glaciers in Northern Tien Shan (Kazakhstan/Kyrgyzstan)
Authors: Bolch Tobias , Gorbunov Aldar P.
Published: December 2014

Northern Tien Shan is characterised by a distinct periglacial belt that contains many rock glaciers with an area of 1 km2 or more. To investigate the reason for their large size and variable occurrence, we analysed a representative subsample of the rock glaciers with respect to topographic and climatic variables. A simple permafrost model indicates that the rock glaciers originate in the zone where permafrost occurrence is very likely and some large rock glaciers flow down to elevations where permafrost is unlikely to exist outside the rock glaciers themselves. Correlation and multiple regression analyses revealed that the occurrence and characteristics of the rock glaciers can only be partly explained by the characteristics of the contributing area (e.g. its area or the headwall height). The correlation is greater with talus‐type rock glaciers than with moraine‐type rock glaciers. The climate can explain the general occurrence of rock glaciers but not their specific characteristics. It is hypothesised that the main reason for the specific distribution and characteristics of these large rock glaciers relates to the interaction with polythermal glaciers, topographic characteristics, intensive weathering and rock avalanches triggered by seismic activity. Copyright © 2014 John Wiley & Sons, Ltd.