bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

BACKGROUNDEndocrine 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.METHODSA 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.RESULTSAfter 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.CONCLUSIONSIn 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

AbstractThe 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

AbstractImidazolium 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

AbstractIn 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

AbstractIn 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

AbstractPostcombustion 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

AbstractAimsRight 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 resultsThis 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).ConclusionDespite 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

AbstractThe 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

AbstractIn 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

Abstract

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

Abstract
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

AbstractNatural 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

ABSTRACT

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

AbstractBACKGROUNDA 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).RESULTSCompared 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.CONCLUSIONThis 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

ABSTRACTMany 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.
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.