bluuebunny/crossref_metadata_2025 huggingface dataset:
Endohedrally Filled [Ni@Sn9]4− and [Co@Sn9]5− Clusters in the Neat Solids Na12Ni1−xSn17 and K13−xCo1−xSn17: Crystal Structure and 119Sn Solid‐State NMR Spectroscopy
Authors: Hlukhyy Viktor , Stegmaier Saskia , van Wüllen Leo , Fässler Thomas F.
Published: July 2014

A systematic approach to the formation of endohedrally filled atom clusters by a high‐temperature route instead of the more frequent multistep syntheses in solution is presented. Zintl phases Na12Ni1−xSn17 and K13−xCo1−xSn17, containing endohedrally filled intermetalloid clusters [Ni@Sn9]4− or [Co@Sn9]5− beside [Sn4]4−, are obtained from high‐temperature reactions. The arrangement of [Ni@Sn9]4− or [Co@Sn9]5− and [Sn4]4− clusters, which are present in the ratio 1:2, can be regarded as a hierarchical replacement variant of the hexagonal Laves phase MgZn2 on the Mg and Zn positions, respectively. The alkali‐metal positions are considered for the first time in the hierarchical relationship, which leads to a comprehensive topological parallel and a better understanding of the composition of these compounds. The positions of the alkali‐metal atoms in the title compounds are related to the known inclusion of hydrogen atoms in the voids of Laves phases. The inclusion of Co atoms in the {Sn9} cages correlates strongly with the number of K vacancies in K13−xCo1−xSn17 and K5−xCo1−xSn9, and consequently, all compounds correspond to diamagnetic valence compounds. Owing to their diamagnetism, K13−xCo1−xSn17, and K5−xCo1−xSn9, as well as the d‐block metal free binary compounds K12Sn17 and K4Sn9, were characterized for the first time by 119Sn solid‐state NMR spectroscopy.
Multivalent Inhibitors for Carbohydrate‐Processing Enzymes: Beyond the “Lock‐and‐Key” Concept
Authors: Gouin Sébastien G.
Published: July 2014

During the last decades, tremendous chemical efforts have been dedicated to design monovalent inhibitors of carbohydrate‐processing enzymes, with comparatively few rewards in terms of marketed drugs. Recently, an alternative to the traditional “lock and key” approach has emerged. Multivalency, a widely used strategy for lectin inhibition, has been successfully applied to specific glycosidases and glycosyltransferases.
Geometric Influence on Intramolecular Photoinduced Electron Transfer in Platinum(II) Acetylide‐Linked Donor–Acceptor Assemblies
Authors: Molina‐Ontoria Agustín , Rivera‐Nazario Danisha M. , Tigreros Alexis , Ortiz Alejandro , Nuñez José E. , Insuasty Braulio , Lueders Daniela , Wolfrum Silke , Guldi Dirk M. , Echegoyen Luis
Published: July 2014

A new donor–acceptor system, in which the electron donor triphenylamine (TPA) and the electron acceptor C60 are bridged through a cis‐ or trans‐platinum(II) acetylide spacer have been prepared. Ground‐state studies were conducted using electrochemistry and UV/Vis spectroscopy. Fluorescence studies suggested that charge transfer is the deactivation mechanism for the singlet excited state, and this was verified by transient absorption spectroscopy. Selective photoexcitation of 1 and 2 at 387 nm leads to a fast charge transfer between the TPA and C60, which gives rise to a radical ion‐pair state (TPA.+–Pt–C60.−). Our results suggest that charge transfer is favored for the cis configuration while the presence of the trans configuration in the PtII diacetylide results in a longer‐lived charge separated states.
New Concepts for Designing d10‐M(L)n Catalysts: d Regime, s Regime and Intrinsic Bite‐Angle Flexibility
Authors: Wolters Lando P. , van Zeist Willem‐Jan , Bickelhaupt F. Matthias
Published: July 2014

Our aim is to understand the electronic and steric factors that determine the activity and selectivity of transition‐metal catalysts for cross‐coupling reactions. To this end, we have used the activation strain model to quantum‐chemically analyze the activity of catalyst complexes d10‐M(L)n toward methane CH oxidative addition. We studied the effect of varying the metal center M along the nine d10 metal centers of Groups 9, 10, and 11 (M=Co−, Rh−, Ir−, Ni, Pd, Pt, Cu+, Ag+, Au+), and, for completeness, included variation from uncoordinated to mono‐ to bisligated systems (n=0, 1, 2), for the ligands L=NH3, PH3, and CO. Three concepts emerge from our activation strain analyses: 1) bite‐angle flexibility, 2) d‐regime catalysts, and 3) s‐regime catalysts. These concepts reveal new ways of tuning a catalyst’s activity. Interestingly, the flexibility of a catalyst complex, that is, its ability to adopt a bent L‐M‐L geometry, is shown to be decisive for its activity, not the bite angle as such. Furthermore, the effect of ligands on the catalyst’s activity is totally different, sometimes even opposite, depending on the electronic regime (d or s) of the d10‐M(L)n complex. Our findings therefore constitute new tools for a more rational design of catalysts.
Synthesis and Antiviral Properties of Spirocyclic [1,2,3]‐Triazolooxazine Nucleosides
Authors: Dell'Isola Antonio , McLachlan Matthew M. W. , Neuman Benjamin W. , Al‐Mullah Hawaa M. N. , Binks Alexander W. D. , Elvidge Warren , Shankland Kenneth , Cobb Alexander J. A.
Published: July 2014

An efficient synthesis of spirocyclic triazolooxazine nucleosides is described. This was achieved by the conversion of β‐D‐psicofuranose to the corresponding azido‐derivative, followed by alkylation of the primary alcohol with a range of propargyl bromides, obtained by Sonogashira chemistry. The products of these reactions underwent 1,3‐dipolar addition smoothly to generate the protected spirocyclic adducts. These were easily deprotected to give the corresponding ribose nucleosides. The library of compounds obtained was investigated for its antiviral activity using MHV (mouse hepatitis virus) as a model wherein derivative 3 f showed the most promising activity and tolerability.
An Experimental Study of Wave Velocity Anisotropy in Sandstone Bearing Differential Pore Fluids from the Yanchang Formation
Authors: Er‐Wei QIAO , Chang‐Xing LONG , Hong‐Tao MA
Published: July 2014

This work applied the AutoLab 2000 test system to investigate three kinds of core samples of sandstone from the Yanchang oilfield that were cut parallel and perpendicular to the bedding planes (named H and V, respectively), and obtained accurate P‐ and S‐wave velocities, and wave velocity anisotropy data at pressures up to 180 MPa in dry, water‐ and oil‐saturated states for those sandstone. The results show the wave velocities VP, VSH and VSV for all H and V samples cut from three kinds of samples of sandstone Y1, Y2 and Y3 change basically logarithmically with increasing confining pressure p, and for all VP, the slopes of the oil‐saturated curves are greater than that of the corresponding water‐saturated curves. For all H samples, in dry, water‐ and oil‐saturated conditions, the VP and VSH and VSV are larger than the corresponding ones for V samples. For two kinds of sandstones Y1 and Y2, the wave velocity anisotropy parameters ε, γ and ζ change exponentially or in a quadratic curve with increasing confining pressure, and Y2 has a greater correlation coefficient of anisotropy parameters than Y1, but there is no wave velocities anisotropy in Y3. In addition, in dry, water‐ and oil‐saturated conditions the relationships between ε, γ and p or γ, ζ and p are quite distinct from each other, that is, the anisotropy factors ε, γ and ζ of Y1 and Y2 exhibit a clear correlation with pressure and the fluid property, and ε and γ in oil‐saturated condition are larger than that in the corresponding water‐saturated condition at the experimental pressure. The experimental results can provide an important basis for the interpretation of seismic data, identifying oil and water zones and comparing with well log data in the study area.
Transfemoral Aortic Valve Implantation of Edwards SAPIEN XT Without Predilatation Is Feasible
Authors: Möllmann Helge , Kim Won‐Keun , Kempfert Jörg , Blumenstein Johannes , Liebetrau Christoph , Nef Holger , Van Linden Arnaud , Walther Thomas , Hamm Christian
Published: July 2014

Background

Transcatheter aortic valve implantation (TAVI) without predilatation has fewer procedural steps and thereby potentially fewer complications. This has been demonstrated for the antegrade transapical access; however, whether TAVI can be safely performed without predilatation using the retrograde transfemoral route is unknown.

Hypothesis

We postulated that TAVI is feasible with a balloon‐expandable device without predilatation using the retrograde transfemoral route.

Methods

Twenty‐six consecutive patients with stenosis of the native aortic valve (AV) undergoing transfemoral TAVI with the Edwards SAPIEN XT prosthesis without predilatation were enrolled in this retrospective study and compared with 30 patients treated previously with predilatation.

Results

The procedure was successfully performed in all 26 patients, irrespective of the AV area and the extent of AV calcification. At baseline mean AV area, mean AV gradient, and median left ventricular ejection fraction were 0.7 ± 0.2 cm2, 36.0 ± 17.3 mm Hg, and 55.0% (interquartile range [IQR], 35.0–60.0], respectively; prior to discharge these values were 1.7 ± 0.3 (P < 0.001), 9.8 ± 6.1 mm Hg (P < 0.001), and 57.5% (IQR, 38.7–60.0) (P = not significant). Postdilatation was required in 3 patients due to aortic regurgitation >2°; this was reduced by the procedure to <2° in all cases. Radiation dose and amount of contrast dye were significantly reduced in comparison with the predilatation group. No periprocedural neurological adverse events occurred. Mortality at 30 days was 0%.

Conclusions

TAVI without predilatation using the transfemoral Edwards SAPIEN XT valve is feasible and safe. Larger studies are required to further evaluate this approach.
Impact of sex on the survival of patients with hepatocellular carcinoma: A Surveillance, Epidemiology, and End Results analysis
Authors: Yang Dongyun , Hanna Diana L. , Usher Josh , LoCoco Jordan , Chaudhari Pritesh , Lenz Heinz‐Josef , Setiawan V. Wendy , El‐Khoueiry Anthony
Published: July 2014

BACKGROUND

Men are 4 to 8 times more likely to develop hepatocellular carcinoma (HCC) than women. Preclinical models have suggested a role for sex hormones in the development of HCC. In the current study, the authors investigated the impact of age, sex, race, and ethnicity on the survival of patients with HCC using the Surveillance, Epidemiology, and End Results (SEER) database.

METHODS

Patients diagnosed with HCC from 1988 through 2010 were identified from the SEER registry. Hazard ratios (HR) for overall survival (OS) were derived using the Cox regression model adjusted for race, year of diagnosis, marital status, treatment, birthplace, tumor differentiation, and tumor size.

RESULTS

A total of 39,345 patients were identified; 76% were men and 34% were women (50% white, 12% African American, 21% Asian, 16% Hispanic, and 1% Native American). The median age at the time of diagnosis was 61 years for men and 67 years for women. Approximately 84% of patients had liver‐limited disease and 16% had metastatic disease. Treatment information was available for patients diagnosed after 1998 (34,674 patients): 11% received liver‐directed therapy, 11% underwent surgical resection, and 7% underwent liver transplantation. The HR for the OS of women versus men was 0.83 (95% confidence interval [95% CI], 0.77‐0.88) for patients aged <55 years. The protective effect of sex on OS was found to be greatest in patients aged 18 to 44 years (HR, 0.75; 95% CI, 0.65‐0.86 [P<.001]), especially those with surgically resected tumors (HR, 0.68; 95% CI, 0.54‐0.86 [P = .001]) and those who were African American (HR, 0.85; 95% CI, 0.78‐0.92 [P<.001]). There was no survival difference between sexes noted among Hispanics or patients aged >65 years.

CONCLUSIONS

Sex appears to be associated with survival in patients with HCC. The role of androgens and estrogens in the development and progression of HCC warrants further investigation. Cancer 2014;120:3707–3716. © 2014 American Cancer Society.
Prechemotherapy antimullerian hormone, age, and body size predict timing of return of ovarian function in young breast cancer patients
Authors: Su Hui‐Chun Irene , Haunschild Carolyn , Chung Karine , Komrokian Sara , Boles Sarah , Sammel Mary Dupuis , DeMichele Angela
Published: July 2014

BACKGROUND

Endocrine measures of ovarian reserve before breast cancer treatment may predict postchemotherapy ovarian function, providing prognostic information at the time of cancer diagnosis. The objectives of this study were 1) to determine whether prechemotherapy levels of antimullerian hormone (AMH), follicle‐stimulating hormone (FSH), and inhibin B (inhB) are associated with the return of ovarian function after chemotherapy and 2) to generate a prognostic score for ovarian recovery in young women with breast cancer.

METHODS

A prospective cohort study recruited 109 participants (median age, 39 years; age range, 23‐45 years) before chemotherapy from 2 breast clinics and followed them longitudinally. By using time‐to‐event analysis, the authors tested the association between prechemotherapy AMH, FSH, and inhB levels and the time to return of ovarian function, as measured by menstrual pattern.

RESULTS

After a median follow‐up of 163 days (range, 4‐1009 days) after chemotherapy, 62 participants (57%) experienced return of ovarian function. In adjusted analyses, AMH levels >0.7 ng/mL (hazard ratio, 2.9; 95% confidence interval, 1.5‐5.6) and FSH levels ≤10 IU/L (hazard ratio, 4.7; 95% confidence interval, 1.3‐16.8) were associated with a shorter time to ovarian recovery, whereas inhB levels were not related. A prognostic score based on age <40 years, AMH >0.7 ng/mL, and body mass index ≥25 kg/m2 was used to estimate the timing of recovery.

CONCLUSIONS

In reproductive‐aged women with newly diagnosed breast cancer, prechemotherapy AMH and FSH levels were associated with the return of ovarian function, independent of age. A novel prognostic score incorporating AMH, age, and body size was capable of estimating the time to ovarian recovery. Pending validation, these data support using prechemotherapy ovarian reserve measures, particularly AMH, to prospectively counsel young patients on future ovarian function. Because ovarian function is not equivalent to fertility, follow‐up studies on predicting fertility are needed. Cancer 2014;120:3691–3698. © 2014 American Cancer Society.
Efficient Calculation of Anharmonic Vibrational Spectra of Large Molecules with Localized Modes
Authors: Panek Paweł T. , Jacob Christoph R.
Published: July 2014

The analysis and interpretation of the vibrational spectra of complex (bio)molecular systems, such as polypeptides and proteins, requires support from quantum‐chemical calculations. Such calculations are currently restricted to the harmonic approximation. Here, we show how one of the main bottlenecks in such calculations, the evaluation of the potential energy surface, can be overcome by using localized modes instead of the commonly employed normal modes. We apply such local vibrational self‐consistent field (L‐VSCF) and vibrational configuration interaction (L‐VCI) calculations to a cyclic water tetramer and a helical hexa‐alanine peptide. The results show that the use of localized modes is equivalent to the commonly used normal modes, but offers several advantages. First, a faster convergence with respect to the excitation level is observed in L‐VCI calculations. Second, the localized modes provide a reduced representation of the couplings between modes that show a regular coupling pattern. This can be used to disregard a significant number of small two‐mode potentials a priori. Several such reduced coupling approximations are explored, and we show that the number of single‐point calculations required to evaluate the potential energy surface can be significantly reduced without introducing noticeable errors in the resulting vibrational spectra.
Improving the Alkaline Stability of Imidazolium Cations by Substitution
Authors: Dong Huilong , Gu Fenglou , Li Min , Lin Bencai , Si Zhihong , Hou Tingjun , Yan Feng , Lee Shuit‐Tong , Li Youyong
Published: July 2014

Imidazolium cations are promising candidates for preparing anion‐exchange membranes because of their good alkaline stability. Substitution of imidazolium cations is an efficient way to improve their alkaline stability. By combining density functional theory calculations with experimental results, it is found that the LUMO energy correlates with the alkaline stability of imidazolium cations. The results indicate that alkyl groups are the most suitable substituents for the N3 position of imidazolium cations, and the LUMO energies of alkyl‐substituted imidazolium cations depend on the electron‐donating effect and the hyperconjugation effect. Comparing 1,2‐dimethylimidazolium cations (1,2‐DMIm+) and 1,3‐dimethylimidazolium cations (1,3‐DMIm+) with the same substituents reveals that the hyperconjugation effect is more significant in influencing the LUMO energy of 1,3‐DMIms. This investigation reveals that LUMO energy is a helpful aid in predicting the alkaline stability of imidazolium cations.
The Oxygen Reduction Reaction in Ferrofluids: Towards Membrane‐less and Spill‐less Gas Sensors
Authors: Panchompoo Janjira , Ge Mengchen , Zhao Chuan , Lim May , Aldous Leigh
Published: July 2014

In this study, a “membrane‐less and spill‐less” gas‐sensing device has been evaluated for the electrochemical detection of oxygen. Iron oxide magnetic nanoparticles were prepared by chemical co‐precipitation and used to prepare an aqueous ferrofluid. The iron oxide nanoparticles were subsequently stabilised and passivated with a cationic polymer, namely, poly(diallyldimethyl ammonium chloride). The resulting ferrofluid was evaluated as an electrolyte for the analytical quantification of oxygen on screen‐printed carbon electrodes. An applied magnetic field immobilised the ferrofluid electrolyte in place to result in a “membrane‐less and spill‐less” ferrofluid‐based gas sensor. The polymer poly(diallyldimethyl ammonium chloride) was found to result in an apparent enhancement in the electrocatalysis of the system towards the oxygen reduction reaction. Furthermore, as the strength of the applied magnetic field was increased, the oxygen reduction current also increased owing to the response of the polymer‐coated nanoparticles. The oxygen reduction current was linear from 0 to 100 % oxygen content.
Regioselective Air Oxidation of Sulfides to O,S‐Acetals in a Bubble Column
Authors: Brockmeyer Fabian , Martens Jürgen
Published: July 2014

In this paper the use of a bubble column for a metal‐free, selective oxidation of α‐alkylthio‐imines to O,S‐acetals is presented. During the synthesis, which is straightforward to perform, the sulfides are oxidized to α‐alkoxy‐ or, respectively, α‐hydroxysulfide by adding activated carbon in the presence of atmospheric oxygen only. We show that the use of the bubble column, which is unusual on laboratory scale, improves the efficiency of the reaction in comparison to common laboratory techniques. As atmospheric oxygen alone is used for oxidation, this method is cost saving, environmentally friendly, and safe.
Directed Synthesis of Nanoporous Carbons from Task‐Specific Ionic Liquid Precursors for the Adsorption of CO2
Authors: Mahurin Shannon M. , Fulvio Pasquale F. , Hillesheim Patrick C. , Nelson Kimberly M. , Veith Gabriel M. , Dai Sheng
Published: July 2014

Postcombustion CO2 capture has become a key component of greenhouse‐gas reduction as anthropogenic emissions continue to impact the environment. We report a one‐step synthesis of porous carbon materials using a series of task‐specific ionic liquids for the adsorption of CO2. By varying the structure of the ionic liquid precursor, we were able to control pore architecture and surface functional groups of the carbon materials in this one‐step synthesis process leading to adsorbents with high CO2 sorption capacities (up to 4.067 mmol g−1) at 0 °C and 1 bar. Added nitrogen functional groups led to high CO2/N2 adsorption‐selectivity values ranging from 20 to 37 whereas simultaneously the interaction energy was enhanced relative to carbon materials with no added nitrogen.
Echocardiographic and clinical response to cardiac resynchronization therapy in heart failure patients with and without previous right ventricular pacing
Authors: Gage Ryan M. , Burns Kevin V. , Bank Alan J.
Published: July 2014

Aims

Right ventricular pacing (RVp) results in an electrocardiographic left bundle branch block pattern and can lead to heart failure. This study aimed to evaluate echocardiographic and clinical outcomes of heart failure patients with RVp upgraded to cardiac resynchronization therapy (CRT), as they are frequently excluded from multicentre studies.

Methods and results

This observational study assessed 655 consecutive patients with QRS ≥120 ms and left ventricular ejection fraction ≤35%. There were 465 patients without significant previous RVp and 190 with RVp >40%. Echocardiograms were analysed pre‐CRT and ∼ 1 year post‐CRT. Death and heart failure hospitalizations were analysed using Cox regression, adjusted for baseline characteristics. The RVp patients had smaller end‐systolic volume (P = 0.002), were older (P < 0.001), and had more atrial fibrillation (P < 0.001) pre‐CRT. Ejection fraction and proportion of ischaemic aetiology were similar. One year following CRT implantation the ejection fraction response was greater in the RVp group (8.3 ± 9 vs. 5.8 ± 9 units, P = 0.005). The RVp patients had an adjusted 33% lower risk of death or heart failure hospitalization [hazard ratio (HR) 0.67 95% confidence interval (CI) 0.51–0.89, P = 0.005], while tending to have an adjusted lower risk of death (HR 0.73 95% CI 0.53–1.01, P = 0.055).

Conclusion

Despite similar ejection fraction pre‐CRT, patients upgraded to CRT with previous RVp have smaller end‐systolic volume and respond to CRT at least as well as, if not better than, other wide QRS heart failure patients. A greater improvement in ejection fraction and a lower risk of death or heart failure hospitalization when adjusted for baseline characteristics were seen in those with previous RVp.
Is the privacy paradox a relic of the past? An in‐depth analysis of privacy attitudes and privacy behaviors
Authors: Dienlin Tobias , Trepte Sabine
Published: July 2014

The privacy paradox states that online privacy concerns do not sufficiently explain online privacy behaviors on social network sites (SNSs). In this study, it was first asked whether the privacy paradox would still exist when analyzed as in prior research. Second, it was hypothesized that the privacy paradox would disappear when analyzed in a new approach. The new approach featured a multidimensional operationalization of privacy by differentiating between informational, social, and psychological privacy. Next to privacy concerns, also, privacy attitudes and privacy intentions were analyzed. With the aim to improve methodological aspects, all items were designed on the basis of the theory of planned behavior. In an online questionnaire with N = 595 respondents, it was found that online privacy concerns were not significantly related to specific privacy behaviors, such as the frequency or content of disclosures on SNSs (e.g., name, cell‐phone number, or religious views). This demonstrated that the privacy paradox still exists when it is operationalized as in prior research. With regard to the new approach, all hypotheses were confirmed: Results showed both a direct relation and an indirect relation between privacy attitudes and privacy behaviors, the latter mediated by privacy intentions. In addition, also an indirect relation between privacy concerns and privacy behaviors was found, mediated by privacy attitudes and privacy intentions. Therefore, privacy behaviors can be explained sufficiently when using privacy attitudes, privacy concerns, and privacy intentions within the theory of planned behavior. The behaviors of SNS users are not as paradoxical as was once believed. Copyright © 2014 John Wiley & Sons, Ltd.
Non‐Invasive Monitoring of Osteogenic Differentiation on Microtissue Arrays under Physiological Conditions Using Scanning Electrochemical Microscopy
Authors: Sridhar Adithya , van den Berg Albert , Le Gac Séverine
Published: July 2014

In this paper, we present a non‐invasive assay using scanning electrochemical microscopy (SECM) for detecting osteogenic differentiation at physiological conditions (pH 7.5) on arrays of C2C12 microtissues. Upon exposure to bone morphogenic protein 2 (BMP‐2), C2C12 microtissues differentiate and express alkaline phosphatase (ALP), which is indirectly detected through an enzymatic assay producing an electroactive species. The latter is detected using SECM by scanning at constant height over live microtissues at physiological pH (7.5) as well as more alkaline pH (8.5). As a control, expression of ALP is confirmed using a standard colorimetric assay. Detecting differentiation on live samples at physiological conditions represents a significant improvement for continuous monitoring of tissue differentiation or further use of the microtissues for, e.g., regenerative medicine.
Enantioselective toxicity and degradation of the chiral insecticide fipronil in Scenedesmus obliguus suspension system
Authors: Qu Han , Ma Rui-xue , Liu Dong-hui , Wang Peng , Huang Le-dan , Qiu Xing-xu , Zhou Zhi-qiang
Published: July 2014

Fipronil is an effective insecticide, but it presents highly toxic effects in nontarget aquatic organisms. The present study examined the enantioselective toxicity and degradation of fipronil enantiomers in a freshwater algae Scenedesmus obliguus suspension. There was a substantial difference in the acute toxicity of the enantiomers to S. obliguus, with 72-h median effective concentrations (EC50s) of 0.29 mg L−1 and 1.50 mg L−1 for the R-fipronil and S-fipronil, respectively. The influences on the concentration of chlorophyll a, chlorophyll b, and carotenoids were determined, and the effects of fipronil on the concentration of chlorophyll a and chlorophyll b were also enantioselective. The degradation of fipronil in algae suspension was enantioselective, with half-lives for R-fipronil and S-fipronil of 2.9 d and 3.2 d, respectively, and the enantiomer fraction reaching 0.65 at the day 17. The enantiomeric differences should be taken into consideration for fipronil risk assessment. Environ Toxicol Chem 2014;33:2516–2521. © 2014 SETAC
Does the interferon-lambda rather than the interferon-alpha pathway determine the outcome of hepatitis C virus infection?
Authors: Mihm Sabine , Spengler U. , Amanzada Ahmad , Ramadori Giuliano
Published: July 2014

The molecular mechanisms that link IFN-λ3 genotypes to differential induction of interferon (IFN)-stimulated genes (ISGs) in the liver of patients with chronic hepatitis C (CHC) are not known. We measured the expression of IFN-λ and of the specific IFN-λ receptor chain (IFN-λR1) in 122 liver biopsies of patients with CHC and 53 control samples. The IFN-λ3 genotype was not associated with differential expression of IFN-λ, but rather IFN-λR1. In a series of 30 primary human hepatocyte (PHH) samples, IFN-λR1 expression was low but could be induced with IFN-α. IFN-α-induced IFN-λR1 expression was significantly stronger in PHHs carrying the minor IFN-λ3 allele. The analysis of liver biopsies of patients with CHC revealed a strong association of high IFN-λR1 expression with elevated ISG expression, with IFN-λ3 minor alleles, and with nonresponse to pegylated IFN-α and ribavirin. The findings provide a missing link between the IFN-λ3 genotype and the associated phenotype of treatment nonresponse.
Modeling Non‐Native Interactions in Designed Proteins
Authors: Yadahalli Shilpa , Hemanth Giri Rao V. V. , Gosavi Shachi
Published: July 2014

Natural proteins have evolved amino acid sequences that provide a native‐structural bias to folding. Structure‐based models (SBMs) of proteins ignore all non‐native interactions and encode this bias by including only interactions present in the native state. SBMs have been remarkably successful at describing the folding mechanisms and folding rates of natural proteins. Non‐native interaction‐enhanced SBMs (eSBMs) of proteins have been developed to understand non‐native traps observed experimentally in several contexts (due to binding sites in the protein, in the crowded environment of the cell, etc.). The mathematical description of the non‐native interactions is problem specific and different in each eSBM. We review the commonly used eSBMs and make a detailed comparison of their non‐native potential energy terms. Designed proteins have not had the benefit of evolution and are more likely to have non‐native intermediates. Experiments have detected the presence of non‐native interactions in the folding kinetics of the designed protein Top7. We compare the intermediate ensembles obtained from folding simulations of Top7 using three different eSBMs and comment on the robustness of these intermediates to changes in the form of non‐native interactions. Although the population of some intermediates is dependent upon the nature of non‐native interactions, the consensus structural information that arises from the different eSBMs is consistent with experiments. Furthermore, the intermediate ensembles indicate the biochemical basis for the experimentally observed non‐native interactions. In summary, eSBMs, as a group, are likely to be a powerful tool for understanding the structural and biochemical basis of non‐native interactions in protein folding.
Bone Regeneration With Osteogenically Enhanced Mesenchymal Stem Cells and Their Extracellular Matrix Proteins
Authors: Clough Bret H , McCarley Matthew R , Krause Ulf , Zeitouni Suzanne , Froese Jeremiah J , McNeill Eoin P , Chaput Christopher D , Sampson H Wayne , Gregory Carl A
Published: July 2014

Although bone has remarkable regenerative capacity, about 10% of long bone fractures and 25% to 40% of vertebral fusion procedures fail to heal. In such instances, a scaffold is employed to bridge the lesion and accommodate osteoprogenitors. Although synthetic bone scaffolds mimic some of the characteristics of bone matrix, their effectiveness can vary because of biological incompatibility. Herein, we demonstrate that a composite prepared with osteogenically enhanced mesenchymal stem cells (OEhMSCs) and their extracellular matrix (ECM) has an unprecedented capacity for the repair of critical-sized defects of murine femora. Furthermore, OEhMSCs do not cause lymphocyte activation, and ECM/OEhMSC composites retain their in vivo efficacy after cryopreservation. Finally, we show that attachment to the ECM by OEhMSCs stimulates the production of osteogenic and angiogenic factors. These data demonstrate that composites of OEhMSCs and their ECM could be utilized in the place of autologous bone graft for complex orthopedic reconstructions. © 2014 American Society for Bone and Mineral Research.
Enhanced catalytic decoloration of Rhodamine B based on 4‐aminopyridine iron coupled with cellulose fibers
Authors: Huang Zhenfu , Ye Yuting , Zhu Shun , Yao Yuyuan , Lu Wangyang , Chen Wenxing
Published: July 2014

BACKGROUND

A novel heterogeneous Fenton‐like catalyst (FePy‐CFs) was prepared by supporting 4‐aminopyridine iron (FePy) onto cellulose fibers (CFs) by covalent bonds for the rapid decoloration of Rhodamine B (RhB).

RESULTS

Compared with the use of homogeneous FePy alone, the introduction of CFs to FePy significantly enhanced the catalytic decoloration of RhB. In addition, repetitive tests revealed that FePy‐CFs could maintain high catalytic activity in 15 successive runs, suggesting FePy‐CFs has excellent sustaining catalytic ability. More importantly, compared with the traditional homogeneous Fenton reagent, the catalytic reaction could proceed over a wider range of pH values from acidic to alkaline. Various scavengers and probe compounds combined with electron paramagnetic resonance (EPR) technology had been used to identify the active species involved in the catalytic system. The results indicated that hydroxyl radicals (•OH), peroxy radicals (•HO2) and high‐valent iron (Fe(IV)) may be responsible for the decoloration of RhB. Furthermore, the effects of operational parameters and thermodynamic parameters have also been investigated.

CONCLUSION

This study not only opens a new perspective for the development of highly efficient catalytic systems, but also extends the potential applications of cellulose fibers in wastewater treatment. © 2014 Society of Chemical Industry
The dawn of chelonian research: Turtles between comparative anatomy and embryology in the 19th century
Authors: MacCord Kate , Caniglia Guido , Moustakas‐Verho Jacqueline E. , Burke Ann C.
Published: July 2014

Many evo‐devo studies of the turtle's shell draw hypotheses and support from historical sources. The groundbreaking works of Cuvier, Geoffroy St. Hilaire, Carus, Rathke, Owen, and others are being revived in modern research, and their centuries‐old understanding of the turtle's shell reconsidered. In the works of these eminent biologists of the 19th century, comparative anatomy and embryology of turtle morphology set the stage for future studies in developmental biology, histology, and paleontology. Given the impact that these works still make on modern research, it is important to develop a thorough appreciation of previous authors, regarding how they arrived at their conclusions (i.e., what counted as evidence?), whether there was debate amongst these authors about shell development (i.e., what counted as an adequate explanation?), and even why these men, some of the most powerful and influential thinkers and anatomists of their day, were concerned with turtles. By tracing and exposing the context and content of turtle shell studies in history, our aim is to inform modern debates about the evolution and development of the turtle's shell. J. Exp. Zool. (Mol. Dev. Evol.) 324B: 169–180, 2015. © 2014 Wiley Periodicals, Inc.
One‐Pot Domino Synthesis of 3‐Amino‐1,2‐dihydroisoquinolines
Authors: Hamri W. , Shyshkina O. O. , Tarasiuk T. M. , Volovnenko T. A. , Mesbah K. , Rhouati S. , Volovenko Y. M. , Medviediev V. V. , Shishkin O. V.
Published: July 2014

A one‐pot method for the synthesis of 3‐amino‐7‐nitro‐1,2‐dihydroisoquinoline‐4‐carbonitriles from 2‐chloro‐5‐nitrobenzylamines and malononitrile has been developed.
Synthesis and Anti‐cancer Activity of 1,3,4‐Thiadiazole and 1,3‐Thiazole Derivatives Having 1,3,4‐Oxadiazole Moiety
Authors: Dawood Kamal M. , Gomha Sobhi M.
Published: July 2014

Reaction of 1,3,4‐oxadiazolyl‐phenylthiourea 3 with hydrazonoyl halides gave the corresponding 1,3,4‐oxadiazolylimino‐1,3,4‐thiadiazoles. Also, treatment of 3 with ethyl chloroacetate and α‐haloketones afforded the corresponding thiazolidinone and thiazole derivatives, respectively. The structures of the synthesized products were confirmed by spectral data. Ten compounds were evaluated for their anti‐cancer activity against the colon carcinoma cell line (HCT‐116). The results revealed that 1,3,4‐thiadiazole derivatives 13d and 19c (IC50 = 0.73 and 0.86 µg/mL, respectively) have promising antitumor activity against colon carcinoma (HCT‐116), and most of the tested compounds showed moderate anti‐cancer activity.
Peripheral neurobiologic mechanisms of antiallodynic effect of warm water immersion therapy on persistent inflammatory pain
Authors: Martins Daniel F. , Brito Rômulo N. , Stramosk Juliana , Batisti Ana P. , Madeira Fernanda , Turnes Bruna L. , Mazzardo‐Martins Leidiane , Santos Adair R.S. , Piovezan Anna P.
Published: July 2014

Water immersion is widely used in physiotherapy and might relieve pain, probably by activating several distinct somatosensory modalities, including tactile, pressure, and thermal sensations. However, the endogenous mechanisms behind this effect remain poorly understood. This study examined whether warm water immersion therapy (WWIT) produces an antiallodynic effect in a model of localized inflammation and whether peripheral opioid, cannabinoid, and adenosine receptors are involved in this effect. Mice were injected with complete Freund's adjuvant (CFA; intraplantar; i.pl.). The withdrawal frequency to mechanical stimuli (von Frey test) was used to determine 1) the effect of WWIT against CFA‐induced allodynia and 2) the effect of i.pl. preadministration of naloxone (a nonselective opioid receptor antagonist; 5 µg/paw), caffeine (a nonselective adenosine receptor antagonist; 150 nmol/paw), 1,3‐dipropyl‐8‐cyclopentylxanthine (DPCPX; a selective adenosine A1 receptor antagonist; 10 nmol/paw), and AM630 (a selective cannabinoid receptor type 2 antagonist; 4 µg/paw) on the antiallodynic effect of WWIT against CFA‐induced allodynia. Moreover, the influence of WWIT on paw inflammatory edema was measured with a digital micrometer. WWIT produced a significant time‐dependent reduction of paw inflammatory allodynia but did not influence paw edema induced by CFA. Naloxone, caffeine, DPCPX, and AM630 injected in the right, but not in the left, hind paw significantly reversed the antiallodynic effect of WWIT. This is the first study to demonstrate the involvement of peripheral receptors in the antiallodynic effect of WWIT in a murine model of persistent inflammatory pain. © 2014 Wiley Periodicals, Inc.
Multiresidue method for the determination of 227 pesticides in hot pepper (Capsicum annuum L.) by liquid chromatography with tandem mass spectrometry†
Authors: Zhu Yong‐Zhe , Zhao Mei‐Ai , Nan Feng Ya , Han Kim Jeong
Published: July 2014

A high‐throughput, rapid, and efficient modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with a simple cleanup procedure has been developed for simultaneously determining 227 pesticides in pepper samples by liquid chromatography with tandem mass spectrometry (running time: 10 min). Pesticide residues were extracted/partitioned with an acetonitrile/DisQuE QuEChERS pouch, and the resulting samples were cleaned up with different methods: dispersive solid‐phase extraction with primary secondary amines or multiwalled carbon nanotubes and graphitized carbon solid mini cartridge column. The results indicated that multiwalled carbon nanotubes dispersive sorbents achieved the best recoveries and had less matrix interference. The numbers of pesticides with a recovery in the range of 70–120% were 199 at a spiked level of 40 μg/kg. The correlation coefficients (r2) for 227 pesticides were above 0.99, while the limits of quantitation of pesticides in pepper samples ranged from 0.13 to 13.51 μg/kg (S/N = 10), and the limits of detection ranged from 0.04 to 4.05 μg/kg (S/N = 3). The relative standard deviations of approximately 197 pesticides were below 20% at spiked levels of 40 μg/kg. Based on these results, the proposed method was chosen as the most suitable cleanup procedure for the determination of multiresidue pesticides in pepper samples.
Simultaneous determination of galanthamine and lycorine in Lycoris radiata by a capillary electrophoresis with an electrochemiluminescence method
Authors: Wang Yanchao , Zhu Guimei , Li Xia , Hao Zaibin
Published: July 2014

A novel capillary electrophoresis with electrochemiluminescence determination method was developed for the determination of two alkaloids based on the electrochemiluminescence signal enhancement effect of the tertiary amine group on tris(2,2′‐bipyridyl)ruthenium(II). A linear relationship between the electrochemiluminescence peak area and concentrations of galanthamine and lycorine in the range of 0.07 ∼ 17 μg/mL and 0.07 ∼ 18 μg/mL was obtained and the detection limit was 0.008 and 0.002 μg/mL, respectively. The method is selective, simple, and convenient. It had been successfully applied to the analysis of galanthamine and lycorine in Lycoris radiata samples purchased from a local market.
The association between secondhand smoke and sleep‐disordered breathing in children: A systematic review
Authors: Jara Sebastian M. , Benke James R. , Lin Sandra Y. , Ishman Stacey L.
Published: July 2014

Objective

To systematically review existing literature on the association between secondhand smoke and sleep‐disordered breathing in children.

Data Sources

PubMed, Embase, Cochrane CENTRAL, Web of Science, and Scopus.

Review Methods

Inclusion criteria included English‐language papers containing original human data, with seven or more subjects and age <18 years. Data were systematically collected on study design, patient demographics, clinical characteristics/outcomes, and level of evidence. Two investigators independently reviewed all manuscripts.

Results

The initial search yielded 72 abstracts; 18 articles were ultimately included with a total study population of 47,462 patients. Fifteen (83%) articles found a statistically significant association between secondhand smoke and sleep‐disordered breathing. All were case‐control studies. Quality of articles based on the Newcastle‐Ottawa scale averaged 5.8/9 stars. Secondhand smoke was characterized by serum cotinine testing in only two (11%) studies. Sleep‐disordered breathing was quantified by polysomnography in only four (22%) of the studies and only one (6%) classified subject using polysomnography exclusively. Habitual snoring was the most common form of sleep‐disordered breathing studied in 14/18 (78%) studies, whereas obstructive sleep apnea was reported in one (6%) study and sleep‐related hypoxia in another (6%) study.

Conclusions

Although the majority of studies included in this review found a significant association between secondhand smoke and sleep‐disordered breathing, all of them were evidence level 3b, for an overall grade of B (Oxford Centre for Evidence‐based Medicine). Further higher‐quality studies should be performed in the future to better evaluate the relationship between second‐ smoke and sleep‐disordered breathing in children.

Level of Evidence

NA Laryngoscope, 125:241–247, 2015
Thick junction broadband organic photodiodes
Authors: Armin Ardalan , Hambsch Mike , Kim Il Ku , Burn Paul L , Meredith Paul , Namdas Ebinazar B
Published: July 2014

Inorganic semiconductor‐based broadband photodetectors are ubiquitous in imaging technologies such as digital cameras and photometers. Herein a broadband organic photodiode (OPD) that has performance metrics comparable or superior to inorganic photodiodes over the same spectral range is reported. The photodiode with an active layer comprised of a poly[N‐9′‐heptadecanyl‐2,7‐carbazole‐alt‐5,5‐(4′,7′‐di‐2‐thienyl‐2′,1′,3′‐benzothiadiazole)]:[6,6]‐phenyl‐C71‐butyric acid methyl ester bulk heterojunction blend had a dark current < 1 nA/cm2, specific detectivity of ∼1013 Jones, reverse bias −3 dB frequency response of 100 kHz to 1 MHz, and state‐of‐the‐art Linear Dynamic Range for organic photodiodes of nine orders of magnitude (180 dB). The key to these performance metrics was the use of a thick junction (700 nm), which flattened the spectral response, reduced the dark current and decreased performance variations. The strategy also provides a route to large area defect free “monolithic” structures for low noise integrated photo‐sensing, position determination, or contact, non‐focal imaging.
Ten new ATM alterations in Polish patients with ataxia‐telangiectasia
Authors: Podralska Marta Joanna , Stembalska Agnieszka , Ślęzak Ryszard , Lewandowicz‐Uszyńska Aleksandra , Pietrucha Barbara , Kołtan Sylwia , Wigowska‐Sowińska Jadwiga , Pilch Jacek , Mosor Maria , Ziółkowska‐Suchanek Iwona , Dzikiewicz‐Krawczyk Agnieszka , Słomski Ryszard
Published: July 2014

Inherited biallelic mutations of the ATM gene are responsible for the development of ataxia telangiectasia (AT). The objective of the present study was to conduct molecular analysis of the ATM gene in a cohort of 24 Polish patients with ataxia‐telangiectasia with aim being to provide an updated mutational spectrum in Polish AT patients. As a result of molecular analysis, the status of recurrent mutation was confirmed and ten new ATM variants were detected. Application of MLPA analysis allowed the detection of large genomic deletion. Previously, this type of mutation had never been seen in our population. Finally, in silico analysis was carried out for newly detected ATM alterations. In addition, functional analysis was performed to evaluate the effects of intronic variants: c.3402+30_3402+32delATC.
Anticoagulant‐related hospital admissions: serious adverse reactions identified through hospital databases
Authors: Heng Charles , Rybarczyk‐Vigouret Marie Christine , Michel Bruno
Published: July 2014

Purpose

A growing number of patients today receive anticoagulants. These drugs can cause serious adverse reactions leading to patients' hospitalization. The present study aimed to assess the number of hospital admissions as a result of anticoagulant adverse reactions in Alsace, a French region of 1.8 million inhabitants, and to estimate the economic burden associated with their management.

Methods

A retrospective analysis was performed using data extracted from the regional and anonymous hospital Programme de Médicalisation des Systèmes d'Information (PMSI) database to assess the number of hospital admissions and the associated costs. Stays from public and private hospitals were extracted from the database using two International Classification of Diseases, 10th revision, codes referring to anticoagulant drugs: ‘T45.5—Poisoning by anticoagulants’ and ‘Y44.2—Anticoagulants' adverse effect in therapeutic use’. Costs were calculated from official French tariffs.

Results

Within a 2‐year period from 1 Januray 2010 to 31 December 2011, 462 anticoagulant‐related hospital admissions, predominantly in elderly patients, were identified in Alsace. These stays, as a result of anticoagulant adverse reactions, represented a cost of 2 050 127.86 euros (including hospitalization and expensive drugs).

Conclusion

Regional PMSI database constitutes an effective tool to explore anticoagulant‐related hospital admissions. Based on our study, one can state that the cost of anticoagulation therapies lies not only in the price of the drugs but also in the cost of adverse reaction management. Policy makers should be aware of this reality and should focus on better medication supervision in order to improve patient safety and reduce expenses. Copyright © 2014 John Wiley & Sons, Ltd.
Time‐resolved investigation of Cu(In,Ga)Se2 growth and Ga gradient formation during fast selenisation of metallic precursors
Authors: Mainz Roland , Weber Alfons , Rodriguez‐Alvarez Humberto , Levcenko Sergiu , Klaus Manuela , Pistor Paul , Klenk Reiner , Schock Hans‐Werner
Published: July 2014

Ga segregation at the backside of Cu(In,Ga)Se2 solar cell absorbers is a commonly observed phenomenon for a large variety of sequential fabrication processes. Here, we investigate the correlation between Se incorporation, phase formation and Ga segregation during fast selenisation of Cu–In–Ga precursor films in elemental selenium vapour. Se incorporation and phase formation are analysed by real‐time synchrotron‐based X‐ray diffraction and fluorescence analysis. Correlations between phase formation and depth distributions are gained by interrupting the process at several points and by subsequent ex situ cross‐sectional electron microscopy and Raman spectroscopy. The presented results reveal that the main share of Se incorporation takes place within a few seconds during formation of In–Se at the top part of the film, accompanied by outdiffusion of In out of a ternary Cu–In–Ga phase. Surprisingly, CuInSe2 starts to form at the surface on top of the In–Se layer, leading to an intermediate double graded Cu depth distribution. The remaining Ga‐rich metal phase at the back is finally selenised by indiffusion of Se. On the basis of a proposed growth model, we discuss possible strategies and limitations for the avoidance of Ga segregation during fast selenisation of metallic precursors. Solar cells made from samples selenised with a total annealing time of 6.5 min reached conversion efficiencies of up to 14.2 % (total area, without anti‐reflective coating). The evolution of the Cu(In,Ga)Se2 diffraction signals reveals that the minimum process time for high‐quality Cu(In,Ga)Se2 absorbers is limited by cation ordering rather than Se incorporation. Copyright © 2014 John Wiley & Sons, Ltd.