bluuebunny/crossref_metadata_2025 huggingface dataset:
Developmental signaling: Does it bridge the gap between cilia dysfunction and renal cystogenesis?
Authors: Tran Pamela V. , Sharma Madhulika , Li Xiaogang , Calvet James P.
Published: May 2014

For more than a decade, evidence has accumulated linking dysfunction of primary cilia to renal cystogenesis, yet molecular mechanisms remain undefined. The pathogenesis of renal cysts is complex, involving multiple cellular aberrations and signaling pathways. Adding to this complexity, primary cilia exhibit multiple roles in a context‐dependent manner. On renal epithelial cells, primary cilia act as mechanosensors and trigger extracellular Ca2+ influx in response to laminar fluid flow. During mammalian development, primary cilia mediate the Hedgehog (Hh), Wnt, and Notch pathways, which control cell proliferation and differentiation, and tissue morphogenesis. Further, experimental evidence suggests the developmental state of the kidney strongly influences renal cystic disease. Thus, we review evidence for regulation of Ca2+ and cAMP, key molecules in renal cystogenesis, at the primary cilium, the role of Hh, Wnt, and Notch signaling in renal cystic disease, and the interplay between these developmental pathways and Ca2+ signaling. Indeed if these developmental pathways influence renal cystogenesis, these may represent novel therapeutic targets that can be integrated into a combination therapy for renal cystic disease. Birth Defects Research (Part C) 102:159–173, 2014. © 2014 Wiley Periodicals, Inc.
Recursive confidence band construction for an unknown distribution function
Authors: Kiatsupaibul Seksan , Hayter Anthony J.
Published: May 2014

Given a sampleof independent observations from an unknown continuous distribution functionF, the problem of constructing a confidence band forFis considered, which is a fundamental problem in statistical inference. This confidence band provides simultaneous inferences on all quantiles and also on all of the cumulative probabilities of the distribution, and so they are among the most important inference procedures that address the issue of multiplicity. A fully nonparametric approach is taken where no assumptions are made about the distribution functionF. Historical approaches to this problem, such as Kolmogorov's famous () procedure, represent some of the earliest inference methodologies that address the issue of multiplicity. This is because a confidence band at a given confidence levelallows inferences on all of the quantiles of the distribution, and also on all of the cumulative probabilities, at that specified confidence level. In this paper it is shown how recursive methodologies can be employed to construct both one‐sided and two‐sided confidence bands of various types. The first approach operates by putting bounds on the cumulative probabilities at the data points, and a recursive integration approach is described. The second approach operates by providing bounds on certain specified quantiles of the distribution, and its implementation using recursive summations of multinomial probabilities is described. These recursive methodologies are illustrated with examples, and R code is available for their implementation.
Optimization of supercritical fluid extraction method for detection of fluquinconazole and tetraconazole in soil using gas chromatography and confirmation using GC‐MS: application to dissipation kinetics
Authors: Park Sang Im , Park Jong‐Hyouk , Ko Ah‐Young , Abd El‐Aty A. M. , Goudah Ayman , Jang Jin , Rahman Md. Musfiqur , Kim Mi Ra , Shim Jae‐Han
Published: May 2014

The aim of this study was to establish an analytical method to detect fluquinconazole and tetraconazole in soil using supercritical fluid extraction (SFE) and gas chromatography (GC). The optimal extraction conditions for SFE were: temperature, 60 °C; pressure, 280 kg/cm2; extraction time, 50 min; and a 10% modifier ratio. The linearity of the calibration curves was good and yielded a determination coefficient (R2) ≥ 0.995. The soil samples were fortified with known quantities of the analytes at three different concentrations (0.01, 0.02 and 0.1 µg/g for fluquinconazole; 0.05, 0.1 and 0.5 µg/g for tetraconazole), and the recoveries ranged between 83.7 and 94.1%. The intra‐ and inter‐day relative standard deviations were 1.3–10.6 and 2.2–11.9% for fluquinconazole and tetraconazole, respectively. The limit of detection and limit of quantitation were 0.002 and 0.01 µg/g for fluquinconazole and 0.01 and 0.05 for tetraconazole, respectively. The method was successfully applied to the analysis of soil residues collected from an onion field. The results show that a combination of SFE and GC can be used as an environmentally friendly technique to detect fungicides in soil. Copyright © 2014 John Wiley & Sons, Ltd.
Comprehensive and temporal analysis of secreted proteins in the medium from IL‐6 exposed human hepatocyte
Authors: Nakata Katsunori , Saitoh Ryoichi , Amano Jun , Ichibangase Tomoko , Ishigai Masaki , Imai Kazuhiro
Published: May 2014

We have previously identified intracellular secretory acute phase response (sAPR) proteins in human hepatocytes following interleukin‐6 (IL‐6) induction by fluorogenic derivatization (FD)–liquid chromatography (LC)–tandem mass spectrometry (MS/MS). In this report, we utilized this method, which uses 7‐chloro‐N‐[2‐(dimethylamino)ethyl]‐2,1,3‐benzoxadiazole‐4‐sulfonamide (DAABD‐Cl) as the FD reagent, to comprehensively and time‐dependently analyze secreted proteins in the medium, including sAPR proteins. Since DAABD‐Cl selectively reacts with thiol moieties of cysteinyl residues, direct derivatization, high‐resolution LC separation and identification of the secreted proteins in the culture medium were successfully achieved without a pretreatment step. As a result, 14 sAPR proteins were identified simultaneously during a 72 h induction by IL‐6. The secretion levels of 11 proteins increased, whereas the secretion levels of three important transport proteins decreased (albumin, retinol‐binding protein 4 and transthyretin). In addition, the secretion level of a haptoglobin was found to increase significantly between 0 and 6 h by 1.88‐fold compared with the control sample. The secretion levels of four cytoplasmic proteins increased: LDH, a known marker for cell damage, and GSTA1, FABP1 and ADH1B, which are marker proteins for hepatocellular damage. The secretion levels of the other two newly identified cytoplasmic proteins, profilin‐1 and SOD2, were also found to increase, suggesting that these two proteins represent novel markers for cell damage. These results suggest that the FD‐LC‐MS/MS proteomics method can be used to analyze comprehensively and time‐dependently the secreted proteins and thereby can offer information that aids our understanding of the dynamics of protein secretion affected by the exposure of cytokines such as IL‐6. Copyright © 2013 John Wiley & Sons, Ltd.
Analysis of etoxazole in red pepper after major modification of QuEChERS for gas chromatography–nitrogen phosphorus detection
Authors: Jang Jin , Rahman Md. Musfiqur , Abd El‐Aty A. M. , Ko Ah‐Young , Park Jong‐Hyouk , Choi Jeong‐Heui , Park Ki. Hun , Yang Angel , Seo Young Mi , Shim Jae‐Han
Published: May 2014

A major modification to the QuEChERS (quick, easy, cheap, effective, rugged and safe) method was developed for the analysis of etoxazole in red pepper using gas chromatography coupled with a nitrogen–phosphorus detector. Etoxazole was extracted with acetonitrile, partitioned with magnesium sulfate and purified with a solid‐phase extraction cartridge. The method showed good linearity with a determination coefficient (R2) of 0.998 for the 0.02–2.0 mg/L concentration range. The method was validated using blank red pepper spiked at 0.2 and 1.0 mg/kg, and the average recovery rate was 74.4–79.1% with relative standard deviations <5% for intra‐ and inter‐day precision. The limits of detection and quantification were 0.007 and 0.02 mg/kg, respectively. The developed method was successfully applied to field‐incurred samples, and the presence of etoxazole residues was confirmed using gas chromatography/mass spectrometry. Copyright © 2014 John Wiley & Sons, Ltd.
Quantitation of P450 3A4 endogenous biomarker – 4β‐hydroxycholesterol – in human plasma using LC/ESI‐MS/MS
Authors: Huang Mike‐Qingtao , Lin Weisheng , Wang Weimin , Zhang Wei , Lin Zhongping (John) , Weng Naidong
Published: May 2014

4β‐Hydroxycholesterol (4β‐HC) has been proposed as a new endogenous biomarker for cytochrome P450 3A4/5 activity. Therefore, it is important to have a robust method for its accurate determination in human plasma. Here a liquid chromatography–tandem mass spectrometry with electrospray ionization (LC/ESI‐MS/MS) assay for the quantitation of 4β‐HC in human plasma is described. While the calibration standards were prepared in a surrogate matrix for human plasma, the quality control samples were prepared in human plasma to mimic the incurred study samples. In order to achieve accurate determination of 4β‐HC, the chromatographic separation of 4β‐HC from its isomers, especially 4α‐hydroxycholesterol (4α‐HC), was crucial. In the absence of an authentic 4α‐HC standard at the time of this study, an alternative selectivity test strategy was developed to confirm the separation. After being alkalized with potassium hydroxide, the human plasma sample (50 μL) was extracted with hexane, derivatized into picolinyl esters using picolinic acid, extracted again with hexane, and then analyzed by LC/ESI‐MS/MS. The calibration curve range was 5–500 ng/mL and the chromatographic separation was achieved on a 50 × 2.1 mm Thermal Hypersil Gold column with a gradient elution. The assay accuracy, precision, linearity, selectivity and analyte stability throughout the analysis were established. The validated assay was successfully applied to a Phase I clinical study for the measurement of 4β‐HC in human plasma. Copyright © 2014 John Wiley & Sons, Ltd.
Development and validation of UHPLC method for the determination of cyclosporine A in biological samples
Authors: Szerkus Oliwia , Wolska Eliza , Struck‐Lewicka Wiktoria , Siluk Danuta , Radwańska Aleksandra , Wiczling Paweł , Chorążewicz Juliusz , Sznitowska Małgorzata , Markuszewski Michał J. , Kaliszan Roman
Published: May 2014

The aim of the study was to develop and validate a simple and rapid method for the determination of cyclosporine A (CsA) in ocular rabbit tissues using reversed‐phase ultra‐high‐performance liquid chromatography (UHPLC) with UV detection. Previous publications on chromatographic methods of CsA determination in ocular tissues involved only reversed‐phase HPLC separation, usually in combination with such detection techniques as radio‐immunoassay and mass spectrometry. The application of the UHPLC technique allowed us to significantly decrease the analysis time. Cyclosporine D (CsD) was applied as the internal standard. Satisfactory separation was achieved on an XB‐C18 Kinetex column at 60°C with the use of gradient elution mode. The retention times of CsA and CsD were found to be 4.5 and 5.1 min, respectively. The developed assay is specific, sensitive (limit of detection = 6 ng/mL and limit of quantitation = 18 ng/mL) and linear within the analyte concentration range of 0.018–5 µg/mL, with a correlation coefficient of 0.999. High sensitivity, low injection volume (10 μL), short time of analysis (6.5 min) and simplicity make this method useful for the fast analysis of CsA in rabbit ocular tissues and fluids: lacrimal fluid, aqueous humor, cornea, conjunctiva and eye globe. Copyright © 2014 John Wiley & Sons, Ltd.
Liquid chromatographic enantioseparation of (RS)‐mexiletine and (RS)‐fluoxetine using chiral derivatizing reagents synthesized with (S)‐naproxen moiety
Authors: Batra Sonika , Bhushan Ravi
Published: May 2014

Enantiomeric separation of racemic mexiletine and fluoxetine was achieved using three chiral derivatizing reagents (CDRs) based on (S)‐naproxen. Diastereomers were synthesized by reaction of mexiletine or fluoxetine with the CDRs and were separated on a C18 column under reversed‐phase conditions using a binary mixture of acetonitrile and triethylammonium phosphate/water, with UV detection at 230 and 226 nm. The results obtained for enantioseparation of the two drugs using the three CDRs were compiled and compared. The conditions for derivatization and chromatographic separation were optimized. The method was validated for linearity, repeatability, limit of detection and limit of quantification. Copyright © 2014 John Wiley & Sons, Ltd.
Microextraction by packed sorbent: an emerging, selective and high‐throughput extraction technique in bioanalysis
Authors: Pereira Jorge , Câmara José S. , Colmsjö Anders , Abdel‐Rehim Mohamed
Published: May 2014

Sample preparation is an important analytical step regarding the isolation and concentration of desired components from complex matrices and greatly influences their reliable and accurate analysis and data quality. It is the most labor‐intensive and error‐prone process in analytical methodology and, therefore, may influence the analytical performance of the target analytes quantification. Many conventional sample preparation methods are relatively complicated, involving time‐consuming procedures and requiring large volumes of organic solvents. Recent trends in sample preparation include miniaturization, automation, high‐throughput performance, on‐line coupling with analytical instruments and low‐cost operation through extremely low volume or no solvent consumption. Micro‐extraction techniques, such as micro‐extraction by packed sorbent (MEPS), have these advantages over the traditional techniques. This paper gives an overview of MEPS technique, including the role of sample preparation in bioanalysis, the MEPS description namely MEPS formats (on‐ and off‐line), sorbents, experimental and protocols, factors that affect the MEPS performance, and the major advantages and limitations of MEPS compared with other sample preparation techniques. We also summarize MEPS recent applications in bioanalysis. Copyright © 2014 John Wiley & Sons, Ltd.
Improved separation of fluorogenic derivatized intact proteins with high resolution and efficiency using a reversed‐phase liquid chromatographic system
Authors: Ichibangase Tomoko , Nakata Katsunori , Imai Kazuhiro
Published: May 2014

Although the efficient separation of intact protein mixtures is extremely difficult, reversed‐phase chromatography is an important technique for performing quantitative, accurate and reproducible proteomics analyses. Here, we show that, despite the operating constraints of conventional high‐performance liquid chromatography, such as column temperature, operating pressure and separation time, comprehensive separation of fluorogenic derivatized intact proteins could be achieved with high resolution and separation efficiency. First, amylin was chosen as a model peptide and used to estimate the separation efficiency with respect to column temperature and flow rate, as indicated by peak capacity. Then, an extract of human primary hepatocytes was used to model complex component mixtures and the separation conditions were optimized. The effects of mobile‐phase pH, the separation time and the column length were also investigated. Consequently, more than 890 peaks could be separated efficiently in the extract, which is 1.5‐fold greater than when using conventional conditions. Finally, it was demonstrated that both longer separation time and column length contributed greatly to the effective separation of the protein mixture. These results are expected to provide insights into the separation of intact proteins. Copyright © 2014 John Wiley & Sons, Ltd.
Enantioseparation of meptazinol and its three intermediate enantiomers by capillary electrophoresis using a new cationicβ‐cyclodextrin derivative in single and dual cyclodextrin systems
Authors: Yu Jia , Zhao Yunfeng , Song Jiaxin , Guo Xingjie
Published: May 2014

A new cationicβ‐cyclodextrin derivative, mono‐6‐deoxy‐6‐piperdine‐β‐cyclodextrin (PIP‐β‐CD), was synthesized and applied as a chiral selector for the enantioseparation of meptazinol and its three intermediate enantiomers (intermediates II–IV) in capillary electrophoresis. When PIP‐β‐CD was employed as the single CD system, intermediate II was baseline enantioseparated while the results for the other analytes were less satisfactory. In order to enhance the selectivity and resolution of meptazinol intermediate III and intermediate IV, dual CD systems of PIP‐β‐CD in combination with three different neutral CDs were synthesized and tested:β‐cyclodextrin (β‐CD), trimethyl‐β‐cyclodextrin (TM‐β‐CD) and hydroxypropyl‐β‐cyclodextrin (HP‐β‐CD). After investigating the effect on the enantioseparation efficiency of the nature and the concentration of both CDs, the dual CD system consisting of PIP‐β‐CD and HP‐β‐CD was shown to be the most efficient for the simultaneous enantioseparation of meptazinol intermediates III and IV. Copyright © 2014 John Wiley & Sons, Ltd.
Dried saliva spot as a sampling technique for saliva samples
Authors: Abdel‐Rehim Abbi , Abdel‐Rehim Mohamed
Published: May 2014

For the first time, dried saliva spot (DSS) was used as a sampling technique for saliva samples. In the DSS technique 50 μL of saliva was collected on filter paper and the saliva was then extracted with an organic solvent. The local anesthetic lidocaine was used as a model compound, which was determined in the DSS using liquid chromatography and mass spectrometry. The results obtained for the determination of lidocaine in saliva using DSS were compared with those from a previous study using a microextraction by packed sorbent syringe as the sampling method for saliva. This study shows that DSS can be used for the analysis of saliva samples. The method is promising and very easy in terms of sampling and extraction procedures. The results from this study are in good agreement with those from our previous work on the determination of lidocaine in saliva. DSS can open a new dimension in the saliva handling process in terms of sampling, storing and transport. Copyright © 2014 John Wiley & Sons, Ltd.
Kidney tissue targeted metabolic profiling of glucocorticoid‐induced osteoporosis and the proposed therapeutic effects of Rhizoma Drynariae studied using UHPLC/MS/MS
Authors: Huang Yue , Liu Xinyu , Zhao Longshan , Li Famei , Xiong Zhili
Published: May 2014

Traditional Chinese medicine and modern science have indicated that there is a close relationship between bone and kidney. In light of this, this project was designed to study the metabolic profiling by UHPLC/MS/MS of glucocorticoid‐induced osteoporosis in kidney tissue and the possible therapeutic effects of Rhizoma Drynariae (RD), a classic traditional Chinese medicine, in improving the kidney function and strengthening bone. Twenty‐one Wistar rats were divided into three groups: control group (rats before prednisolone inducing), a model group (prednisolone‐induced group) and a treatment group (prednisolone‐induced rats that were then administered RD ethanol extracts). By using pattern recognition analysis, a significant change in the metabolic profile of kidney tissue samples was observed in the model group and restoration of the profile was observed after the administration of RD ethanol extracts. Some significantly changed biomarkers related to osteoporosis such as sphingolipids (C16 dihydrosphingosine, C18 dihydrosphingosine, C18 phytosphingosine, C20 phytosphingosine), lysophosphatidycholines (C16:0 LPC, C18:0 LPC) and phenylalanine were identified. As a complement to the metabolic profiling of RD in plasma, these biomarkers suggest that kidney damage, cell cytotoxicity and apoptosis exist in osteoporosis rats, which is helpful in further understanding the underlying process of glucocorticoid‐induced osetoporosis and the suggested therapeutic effects of RD. The method shows that tissue target metabonomics might provide a powerful tool to further understand the process of disease and the mechanism of therapeutic effect of Chinese medicines. Copyright © 2014 John Wiley & Sons, Ltd.
Determination of 4‐hydroxy‐2‐nonenal in serum by high‐performance liquid chromatography with fluorescence detection after pre‐column derivatization using 4‐(N,N‐dimethylaminosulfonyl)‐7‐hydrazino‐2,1,3‐benzoxadiazole
Authors: Imazato Takahiro , Shiokawa Akina , Kurose Yuri , Katou Yasuha , Kishikawa Naoya , Ohyama Kaname , Ali Marwa Fathy Bakr , Ueki Yukitaka , Maehata Eisuke , Kuroda Naotaka
Published: May 2014

4‐Hydroxy‐2‐nonenal (4HNE) is a major aldehyde generated during lipid peroxidation. The clinical monitoring of 4HNE in biological fluids could be useful for the early diagnosis of several diseases involving lipid peroxidation, such as rheumatoid arthritis, Parkinson's disease and cancer. In this study, an HPLC with fluorescence detection method was developed for the determination of 4HNE in human serum. The proposed method involves the extraction of 4HNE from human serum by subzero temperature extraction and fluorescent labeling of 4HNE with 4‐(N,N‐dimethylaminosulfonyl)‐7‐hydrazino‐2,1,3‐benzoxadiazole. The lower detection limit (signal‐to‐noise ratio = 3) of the method was 0.06 µm in serum. The proposed method was successfully applied to the measurement of 4HNE in sera obtained from patients with rheumatoid arthritis. Copyright © 2014 John Wiley & Sons, Ltd.
Preparation of lysozyme molecularly imprinted polymers and purification of lysozyme from egg white
Authors: Wang Xuejiao , Dong Shaohua , Bai Quan
Published: May 2014

Molecular imprinting as a promising and facile separation technique has received much attention because of its high selectivity for target molecules. In this study, lysozyme molecularly imprinted polymers (Lys‐MIPs) were successfully prepared by the entrapment method with lysozyme as the template molecule, acrylamide as the functional monomer and N,N‐methylenebisacrylamide as the cross‐linker. The removal of the template lysozyme from the molecularly imprinted polymers was investigated in detail by two methods. The synthesized Lys‐MIPs were characterized by scanning electron microscopy and Fourier transform–infrared, and the adsorption capacity, selectivity and reproducibility of the Lys‐MIPs were also evaluated. The maximum adsorption capacity reached 94.8 mg/g, which is twice that of nonmolecularly imprinted polymers, and satisfactory selectivity and reproducibility were achieved. Using the Lys‐MIP column, lysozyme could be separated completely from egg white, with purity close to 100% and mass recovery of 98.2%. This illustrated that the synthesized Lys‐MIPs had high specific recognition and selectivity to the template lysozyme when they were applied to a mixture of protein standards and a real sample. Copyright © 2014 John Wiley & Sons, Ltd.
Improved analysis of vitamin D metabolites in plasma using liquid chromatography tandem mass spectrometry, and its application to cardiovascular research
Authors: Sandhu Jatinderpal K. , Auluck Janica , Ng Leong L. , Jones Donald J. L.
Published: May 2014

The accurate and specific measurement of vitamin D is increasingly important for determining the role of vitamin D in the pathogenesis of disease. Liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS) has increasingly become the analytical modality of choice for the analysis of vitamin D. There are many advantages to using LC/MS/MS, such as high specificity and sensitivity to help distinguish the isomers of vitamin D. This rapid method, modified from a Waters Corporation application note, consists of minimal sample manipulation using liquid–liquid extraction and incorporates an internal standard. The supernatant is dried down and injected onto an ultra‐high‐performance liquid chromatography/electrospray ionization tandem mass spectrometer. The total analysis time is 10 min per injection, enabling high throughput of samples. This method also incorporates two commercial quality control standards to provide a robust system with acceptable coefficient of variation. The analysis of control and heart failure plasma samples showed significant differences in the levels of vitamin D3 between these two groups; however, in the control group, there were individuals who were vitamin D deficient. Overall, the vitamin D3 levels were higher in control samples than in heart failure individuals. As expected, vitamin D2 levels were not observed in many of the samples analysed. This modified method is quick and incorporates an internal standard to allow for any loss in the extraction procedure. The method also includes quality control samples to enable assay standardization. The assay involves inexpensive pre‐sample clean‐up, aiding high throughput, which is important in many laboratories. Copyright © 2014 John Wiley & Sons, Ltd.
Emerging K1 serotype Klebsiella pneumoniae primary liver abscess: three cases presenting to a single university hospital in Norway
Authors: Holmås Kristoffer , Fostervold Aasmund , Stahlhut Steen Gustav , Struve Carsten , Holter Jan Cato
Published: May 2014

Key Clinical Message

Community‐acquired Klebsiella pneumoniae primary liver abscess (KLA) has been emerging worldwide over the past two decades and with high incidence in Asia. The presence of specific virulence characteristics is a risk factor for a syndrome with metastatic complications. This report signals an increasing emergence in Northern Europe.
Fe and Mn‐Based Catalysts Supported on γ‐Al2O3 for CO Oxidation under O2‐Rich Conditions
Authors: Tepluchin Marina , Casapu Maria , Boubnov Alexey , Lichtenberg Henning , Wang Di , Kureti Sven , Grunwaldt Jan‐Dierk
Published: May 2014

MnOx and FeOx‐based catalysts supported on γ‐Al2O3 (0.1–20 wt %) were prepared by using two methods: incipient wetness impregnation and single‐step flame spray pyrolysis. The effect of the structural properties and composition on the CO oxidation activity was systematically evaluated and correlated with the preparation methods. The characterization of the samples by XRD, X‐ray absorption spectroscopy, TEM, and temperature‐programmed reduction by hydrogen revealed that, in contrast to the use of incipient wetness impregnation, flame spray pyrolysis leads to the formation of highly dispersed homogeneously distributed FeOx and MnOx species. A partial incorporation of Fe and Mn ions into the γ‐Al2O3 lattice for low metal oxide loadings and for samples prepared by flame spray pyrolysis was observed. In general, the CO oxidation activity increased with the transition metal oxide loading. Below 200 °C, Mn‐based catalysts demonstrated the highest catalytic performance. However, the addition of water decreased the performance, especially at lower temperatures, which demonstrates the competitive adsorption on the active sites. The presence of NO had no effect on the CO conversion. A significant effect of the preparation method on the catalytic performance was observed during hydrothermal aging. The superior distribution of the active species obtained by flame spray pyrolysis leads to thermally more stable catalysts.
On the Nature of Blueshifting Hydrogen Bonds
Authors: Mo Yirong , Wang Changwei , Guan Liangyu , Braïda Benoît , Hiberty Philippe C. , Wu Wei
Published: May 2014

The block‐localized wave function (BLW) method can derive the energetic, geometrical, and spectral changes with the deactivation of electron delocalization, and thus provide a unique way to elucidate the origin of improper, blueshifting hydrogen bonds versus proper, redshifting hydrogen bonds. A detailed analysis of the interactions of F3CH with NH3and OH2shows that blueshifting is a long‐range phenomenon. Since among the various energy components contributing to hydrogen bonds, only the electrostatic interaction has long‐range characteristics, we conclude that the contraction and blueshifting of a hydrogen bond is largely caused by electrostatic interactions. On the other hand, lengthening and redshifting is primarily due to the short‐rangen(Y)→σ*(XH) hyperconjugation. The competition between these two opposing factors determines the final frequency change direction, for example, redshifting in F3CH⋅⋅⋅NH3and blueshifting in F3CH⋅⋅⋅OH2. This mechanism works well in the series FnCl3−nCH⋅⋅⋅Y (n=0–3, Y=NH3, OH2, SH2) and other systems. One exception is the complex of water and benzene. We observe the lengthening and redshifting of the OH bond of water even with the electron transfer between benzene and water completely quenched. A distance‐dependent analysis for this system reveals that the long‐range electrostatic interaction is again responsible for the initial lengthening and redshifting.
Multifunctional 8‐Hydroxyquinoline‐Appended Cyclodextrins as New Inhibitors of Metal‐Induced Protein Aggregation
Authors: Oliveri Valentina , Attanasio Francesco , Puglisi Antonino , Spencer John , Sgarlata Carmelo , Vecchio Graziella
Published: May 2014

Mounting evidence suggests a pivotal role of metal imbalances in protein misfolding and amyloid diseases. As such, metal ions represent a promising therapeutic target. In this context, the synthesis of chelators that also contain complementary functionalities to combat the multifactorial nature of neurodegenerative diseases is a highly topical issue. We report two new 8‐hydroxyquinoline‐appended cyclodextrins and highlight their multifunctional properties, including their CuII and ZnII binding abilities, and capacity to act as antioxidants and metal‐induced antiaggregants. In particular, the latter property has been applied in the development of an effective assay that exploits the formation of amyloid fibrils when β‐lactoglobulin A is heated in the presence of metal ions.
Copper‐Catalyzed Aerobic Oxidative NS Bond Functionalization for CS Bond Formation: Regio‐ and Stereoselective Synthesis of Sulfones and Thioethers
Authors: Li Xianwei , Xu Yanli , Wu Wanqing , Jiang Chang , Qi Chaorong , Jiang Huanfeng
Published: May 2014

A regio‐ and stereoselective synthesis of sulfones and thioethers by means of CuI‐catalyzed aerobic oxidative NS bond cleavage of sulfonyl hydrazides, followed by cross‐coupling reactions with alkenes and aromatic compounds to form the CS bond, is described herein. N2 and H2O are the byproducts of this transformation, thus offering an environmentally benign process with a wide range of potential applications in organic synthesis and medicinal chemistry.
Diazepinoporphyrazines Containing Peripheral Styryl Substituents and Their Promising Nanomolar Photodynamic Activity against Oral Cancer Cells in Liposomal Formulations
Authors: Piskorz Jaroslaw , Konopka Krystyna , Düzgüneş Nejat , Gdaniec Zofia , Mielcarek Jadwiga , Goslinski Tomasz
Published: May 2014

The photochemical properties and photodynamic activity of three porphyrazines (Pzs) containing annulated diazepine rings, including novel demetalated porphyrazine‐possessing bis(styryl)diazepine moieties were investigated. The porphyrazines were evaluated in terms of their electronic absorption and emission properties, their tendency to undergo aggregation and photodegradation, as well as their singlet oxygen generation efficiency. The in vitro photodynamic activity of the porphyrazines and their liposomal formulations were examined by using two oral squamous cell carcinoma cell lines. Magnesium(II) tribenzodiazepinoporphyrazine (1) revealed the highest phototoxic effect in both cell lines used, H413 and HSC‐3. Encapsulation of Pz 1 into L‐α‐phosphatidyl‐d,l‐glycerol:1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine liposomes resulted in a nearly threefold increase in photocytotoxicity relative to that of the solution of Pz 1 (IC50 values of 45 and 129 nM, respectively).
Speed Dependence of Thermochemical Nanolithography for Gray‐Scale Patterning
Authors: Carroll Keith M. , Desai Maitri , Giordano Anthony J. , Scrimgeour Jan , King William P. , Riedo Elisa , Curtis Jennifer E.
Published: May 2014

Thermochemical nanolithography (TCNL) is a high‐resolution lithographic technique and, owing to its fast speed, versatility, and unique ability to fabricate arbitrary, gray‐scale nanopatterns, this scanning probe technique is relevant both for fundamental scientific research as well as for nanomanufacturing applications. In this work, we study the dependence of the TCNL driven chemical reactions on the translation speed of the thermal cantilever. The experimental data compares well with a model of the chemical kinetics for a first‐order reaction. The impact of higher order reactions on the optimization of TCNL is addressed. The reported quantitative description of the speed dependence of TCNL is exploited and illustrated by fabricating controlled gradients of chemical concentration.
Primary cilium and sonic hedgehog signaling during neural tube patterning: Role of GPCRs and second messengers
Authors: Pal Kasturi , Mukhopadhyay Saikat
Published: May 2014

The ventral neural tube in vertebrates is patterned by a gradient of sonic hedgehog (Shh) secreted from the notochord and floor plate. Forward genetic screens first pointed to the role of the primary cilium in ventral neural tube patterning. Further research has shown that most components of the Shh pathway localize to or shuttle through the primary cilium. In the absence of Shh, the bifunctional Gli transcription factors are proteolytically processed into repressor forms in a protein kinase A (PKA)‐ and cilium‐dependent manner. Recent work suggests that the orphan G‐protein‐coupled receptor (GPCR) Gpr161 localizes to cilia, and functions as a negative regulator of Shh signaling by determining Gli processing via cAMP signaling. The primary cilium also functions as a signaling compartment for calcium in the Shh pathway. A better understanding of the role of the cilium as a signaling compartment, and the interplay of second messenger systems that regulate PKA activation and Gli amplification during signaling is critical for deciphering the role of Shh during development, neuronal differentiation, and tumorigenesis. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 75: 337–348, 2015
The loss of control over eating scale: Development and psychometric evaluation
Authors: Latner Janet D. , Mond Jonathan M. , Kelly Mackenzie C. , Haynes Stephen N. , Hay Phillipa J.
Published: May 2014

Objective

This study describes the development, content validity, and convergent validity of the Loss of Control over Eating Scale (LOCES).

Method

An initial pool of 56 items covering 13 facets of loss‐of‐control eating was assembled by reviewing qualitative literature, clinical descriptions, and research on binge eating. Eating disorder experts (n = 34) and eating disorder clients (n = 22) rated each proposed item's clarity and relevance to the construct of loss‐of‐control eating, rated 13 facets for their relevance to the construct, and provided open‐ended feedback about the items and facets. Based on the experts' and clients' quantitative and qualitative feedback, scale items were clarified, 28 items were added, and 10 were deleted. University students (n = 476; 70% female, mean age = 20.4 years) completed the resulting 74‐item questionnaire, rating how often they had the experience identified in the item while eating in the last 4 weeks. They also completed the measures of eating disturbance, general distress, functional impairment, and general self‐control.

Results

The resulting 24‐item LOCES (Cronbach's α = .96) retained items with highest item–total correlations and coverage of the 12 construct facets that experts rated as important. The LOCES was significantly correlated with eating disturbances, general distress, functional impairment, and general self‐control. Three subfactors were identified: behavioral, cognitive/dissociative, and positive/euphoric aspects of loss‐of‐control eating. A brief, seven‐item version of the LOCES was developed and validated.

Discussion

A thorough process of development, content validation, and psychometric evaluation in multiple samples yielded the multifaceted LOCES and its brief form. These instruments may be useful in assessing loss‐of‐control eating in both clinical and nonclinical settings. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2014; 47:647–659)
Obstetric complications and eating disorders: A replication study
Authors: Tenconi Elena , Santonastaso Paolo , Monaco Francesco , Favaro Angela
Published: May 2014

Objective

To provide data about the role of obstetric complications (OCs) in a large and well‐characterized sample of patients with anorexia nervosa (AN) or bulimia nervosa (BN).

Method

The new sample consists of 150 patients with AN and 35 patients with BN, and 73 healthy women; statistical analyses were performed on the new sample alone and on the larger sample created by merging the new dataset with the previous one (264 AN, 108 BN, and 624 healthy women). All data about OCs were collected blind to diagnostic status.

Results

OC rates in the replication sample were similar to those of our previous studies. In the whole sample, the risk of developing AN was significantly associated with the occurrence and number of pregnancy, delivery, hypoxic, and dysmaturity complications. The risk of developing BN was significantly associated with dysmaturity complications. Signs of retarded fetal growth (being small and short for gestational age, short head circumference) significantly distinguished BN patients from both AN and healthy individuals. Significantly higher number of OCs were found in the binge eating/purging type of AN, in comparison with restricting AN patients.

Discussion

Our study provides further evidence of the role of OCs as putative risk factors for the development of eating disorders, showing different pathways between AN and BN. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2015; 48:424–430)
Geographic selection bias of occurrence data influences transferability of invasiveHydrilla verticillatadistribution models
Authors: Barnes Matthew A. , Jerde Christopher L. , Wittmann Marion E. , Chadderton W. Lindsay , Ding Jianqing , Zhang Jialiang , Purcell Matthew , Budhathoki Milan , Lodge David M.
Published: May 2014

Due to socioeconomic differences, the accuracy and extent of reporting on the occurrence of native species differs among countries, which can impact the performance of species distribution models. We assessed the importance of geographical biases in occurrence data on model performance usingHydrilla verticillataas a case study. We used Maxent to predict potential North American distribution of the aquatic invasive macrophyte based upon training data from its native range. We produced a model using all available native range occurrence data, then explored the change in model performance produced by omitting subsets of training data based on political boundaries. We also compared those results with models trained on data from which a random sample of occurrence data was omitted from across the native range. Although most models accurately predicted the occurrence ofH. verticillatain North America (AUC > 0.7600), data omissions influenced model predictions. Omitting data based on political boundaries resulted in larger shifts in model accuracy than omitting randomly selected occurrence data. For well‐documented species likeH. verticillata, missing records from single countries or ecoregions may minimally influence model predictions, but for species with fewer documented occurrences or poorly understood ranges, geographic biases could misguide predictions. Regardless of focal species, we recommend that future species distribution modeling efforts begin with a reflection on potential spatial biases of available occurrence data. Improved biodiversity surveillance and reporting will provide benefit not only in invaded ranges but also within under‐reported and unexplored native ranges.
Trends in prevalence from 1990 to 2007 of patients hospitalized with heart failure in Sweden
Authors: Parén Pär , Schaufelberger Maria , Björck Lena , Lappas Georgios , Fu Michael , Rosengren Annika
Published: May 2014

Aims

To investigate trends in absolute numbers and prevalence from 1990 to 2007 of patients hospitalized with heart failure (HF) in Sweden.

Methods and results

National inpatient and cause‐specific death registers were used to calculate age‐ and sex‐specific trends in absolute numbers and prevalence from 1990 to 2007 of patients hospitalized with HF in Sweden. Absolute numbers increased from 105 449 in 1990 to 144 925 in 2007, with a 77% increase in patients aged 85–99 years. The overall age‐adjusted prevalence in 1990 was 1.73%, and this increased with an estimated annual percentage change (EAPC) of 4.3% [95% confidence interval (CI) 3.6–4.9%] from 1990 to 1995, with no further significant change until 2002. The single year with the highest prevalence was 1998, when it peaked at 2.13%. The prevalence then declined slowly from 2002 (EAPC –1.1, 95% CI −1.5% to −0.6%) to 1.99% in 2007. The decrease in prevalence was not found in persons <65 years, where, instead, an increase was found throughout the period.

Conclusion

Fears of an impending HF ‘epidemic’ could not be confirmed in this analysis of trends in prevalence for the period 1990–2007 of patients hospitalized with HF in Sweden. An overall slight decrease in age‐adjusted prevalence was observed from 2002. The prevalence in patients <65 years increased markedly. In absolute numbers, there was a substantial increase among the very old, consistent with demographic changes.
Synthesis and Characterization of Dibenzoheterocycle‐Bridged Dinuclear Ruthenium Alkynyl and Vinyl Complexes
Authors: Zhang Jing , Ou Yaping , Xu Meng , Sun Chaofang , Yin Jun , Yu Guang‐Ao , Liu Sheng Hua
Published: May 2014

A series of dinuclear ruthenium alkynyl and vinyl complexes bridged by carbazole, dibenzofuran, dibenzothiophene, and fluorenone have been prepared, and some representative molecular structures have been determined. The electrochemical and spectroscopic properties of the compounds were explored by cyclic voltammetry (CV), square‐wave voltammetry (SWV), and in situ infrared and UV/Vis/near‐IR spectroelectrochemical methods. The electrochemical results indicate that the greater the electron density on the ligand, the more stable the bridge‐based oxidation product and the larger the electrochemical splitting. The UV/Vis/near‐IR spectroelectrochemical studies revealed that the bridged ligands strongly contribute to or even dominate the oxidation processes. In addition, IR spectroelectrochemistry strengthens the theory of redox noninnocence in the bridging ligands, which was further confirmed by DFT calculations.
Gold‐Catalyzed Conversion of Aryl‐ and Alkyl‐Substituted 1‐(o‐Aminophenyl)‐2‐propyn‐1‐ones to the Corresponding 2‐Substituted 4‐Quinolones
Authors: Seppänen Otto , Muuronen Mikko , Helaja Juho
Published: May 2014

Gold‐catalyzed cyclization of alkyl‐ or aryl‐substituted 1‐(o‐aminophenyl)‐2‐propyn‐1‐ones to the corresponding 2‐substituted 4‐quinolones was studied with various gold salts and complexes. Screening of the different catalysts showed highest performance with cationic AuI species. In particular PPh3AuNTf2 complex was the most efficient catalyst. Relative to classic quinolone synthesis that requires harsh cyclocondensation conditions, the current method offers a mild and atom‐economic alternative. Mechanistically, DFT studies at TPSS‐D3/def2‐TZVP level suggest that gold operates in an alkynophilic manner rather than through conjugative carbonyl activation.
Crew variability in topographic surveys for monitoring wadeable streams: a case study from the Columbia River Basin
Authors: Bangen Sara , Wheaton Joe , Bouwes Nicolaas , Jordan Chris , Volk Carol , Ward Michael B.
Published: May 2014

Digital elevation models (DEMs) derived from ground‐based topographic surveys have become ubiquitous in the field of fluvial geomorphology. Their wide application in spatially explicit analysis includes hydraulic modeling, habitat modeling, and morphological sediment budgeting. However, there is a lack of understanding regarding the repeatability and precision of DEMs derived from ground‐based surveys conducted by different, and inherently subjective, observers. This is of particular concern when we consider the proportion of studies and monitoring programs that are implemented across multiple sites and over time by different observers. We used a case study from the Columbia Habitat Monitoring Program (CHaMP), where seven field crews sampled the same six sites, to quantify the magnitude and effect of observer variability on DEMs interpolated from total station surveys. We quantified the degree to which DEM‐derived metrics and measured geomorphic change were repeatable. Across all six sites, we found an average elevation standard deviation of 0.05 m among surveys, and a mean total range of 0.16 m. A variance partition between site, crew, and unexplained errors for several topographically derived metrics showed that crew variability never accounted for > 1.5% of the total variability. We calculated minor geomorphic changes at one site following a relatively dry flow year between 2012 and 2011. Calculated changes were minimal (unthresholded net changes ±1–3 cm) with six crews detecting an indeterminate sediment budget and one crew detecting a minor net erosional sediment budget. While crew variability does influence the quality of topographic surveys, this study highlights that when consistent surveying methods are employed, the data sets are still sufficient to support derivation of topographic metrics and conduct basic geomorphic change detection. Copyright © 2014 John Wiley & Sons, Ltd.
Geomorphological factors predict water quality in boreal rivers
Authors: Varanka Sanna , Hjort Jan , Luoto Miska
Published: May 2014

Water quality is the outcome of numerous landscape factors in the catchment. In addition to land use, soil deposits, bedrock and topography are central in different catchment processes and thus important in predicting water quality. In this study, we explored the influence of geomorphological factors at the catchment scale on water quality in 32 boreal rivers in Finland. Water quality was studied through total phosphorus, total nitrogen, pH and water colour, whereas geomorphological factors covered variables from topography, bedrock and surficial ground material (Quaternary soil deposits). Spearman's rank correlation test was used to study the correlations between variables. The relationship between water quality and geomorphology was analysed using novel multivariate methods by fitting of geomorphological vectors and smooth surfaces onto a non‐metric multidimensional scaling (NMDS) scattergram. Hierarchical partitioning (HP) was used to assess the relative importance of geomorphological variables on water quality.

Quaternary soil deposits, especially the covers of clay‐silt and till soils, were important factors in relation to phosphorus and nitrogen based on both NMDS and HP analyses. For example, clay‐silt cover explained over 40% of the variation in these nutrients according to HP. The variation in river water pH was best explained by the covers of sand and open bedrock terrain as well as by catchment topography. Geomorphological variables differed in their effect and relative significance, and thus several geomorphological attributes need to be considered when examining variation in water quality. In conclusion, these results demonstrate that geomorphological factors can be used to predict physical–chemical water quality in a cost‐efficient manner in boreal rivers. NMDS was successfully applied in water quality analyses at the catchment scale. Copyright © 2014 John Wiley & Sons, Ltd.