bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereoselective Synthesis of Fluorinated Galactopyranosides as Potential Molecular Probes for Galactophilic Proteins: Assessment of Monofluorogalactoside–LecA Interactions
Authors: Denavit Vincent , Lainé Danny , Bouzriba Chahrazed , Shanina Elena , Gillon Émilie , Fortin Sébastien , Rademacher Christoph , Imberty Anne , Giguère Denis 
Published: January 2019

AbstractThe replacement of hydroxyl groups by fluorine atoms on hexopyranoside scaffolds may allow access to invaluable tools for studying various biochemical processes. As part of ongoing activities toward the preparation of fluorinated carbohydrates, a systematic investigation involving the synthesis and biological evaluation of a series of mono‐ and polyfluorinated galactopyranosides is described. Various monofluorogalactopyranosides, a trifluorinated, and a tetrafluorinated galactopyranoside have been prepared using a Chiron approach. Given the scarcity of these compounds in the literature, in addition to their synthesis, their biological profiles were evaluated. Firstly, the fluorinated compounds were investigated as antiproliferative agents using normal human and mouse cells in comparison with cancerous cells. Most of the fluorinated compounds showed no antiproliferative activity. Secondly, these carbohydrate probes were used as potential inhibitors of galactophilic lectins. The first transverse relaxation‐optimized spectroscopy (TROSY) NMR experiments were performed on these interactions, examining chemical shift perturbations of the backbone resonances of LecA, a virulence factor from Pseudomonas aeruginosa. Moreover, taking advantage of the fluorine atom, the 19F NMR resonances of the monofluorogalactopyranosides were directly monitored in the presence and absence of LecA to assess ligand binding. Lastly, these results were corroborated with the binding potencies of the monofluorinated galactopyranoside derivatives by isothermal titration calorimetry experiments. Analogues with fluorine atoms at C‐3 and C‐4 showed weaker affinities with LecA as compared to those with the fluorine atom at C‐2 or C‐6. This research has focused on the chemical synthesis of “drug‐like” low‐molecular‐weight inhibitors that circumvent drawbacks typically associated with natural oligosaccharides.
Access to Metal‐Bridged Osmathiazine Derivatives by a Formal [4+2] Cyclization
Authors: Li Jinhua , Lin Yu‐Mei , Zhang Hong , Chen Yuan , Lin Zhenyang , Xia Haiping 
Published: January 2019

AbstractTreatment of osmacyclopentadiene derivatives 1 with phenyl or isopropyl isothiocyanate gave the fused five and six‐membered osmacycles 2–5 by a formal [4+2] cyclization. The facile protonation of the newly generated exocyclic imine in complexes 2–5 afforded conjugation‐extended osmacycle derivatives 6–9. Compounds 2–9 each contain two main‐group heteroatoms (N and S) in the fused six‐membered ring located at the ortho (for S) and para (for N) positions relative to the osmium centre; these species can be regarded as rare osma‐1,3‐thiazine derivatives and represent the first fused metallathiazine derivatives. In contrast to the non‐planar organic 6H‐1,3‐thiazine, nearly coplanar metallathiazines 8 and 9 can be achieved by tuning the groups on the two nitrogen atoms. These unique metal‐bridged osma‐1,3‐thiazine derivatives exhibit remarkable stabilities, broad spectral absorptions spanning the visible spectra, and considerable photothermal properties, which suggests their potential applications in material science.
A phase 2 study of glembatumumab vedotin, an antibody‐drug conjugate targeting glycoprotein NMB, in patients with advanced melanoma
Authors: Ott Patrick A. , Pavlick Anna C. , Johnson Douglas B. , Hart Lowell L. , Infante Jeffrey R. , Luke Jason J. , Lutzky Jose , Rothschild Neal E. , Spitler Lynn E. , Cowey C. Lance , Alizadeh Aaron R. , Salama April K. , He Yi , Hawthorne Thomas R. , Bagley Rebecca G. , Zhang Joshua , Turner Christopher D. , Hamid Omid 
Published: January 2019

BackgroundGlembatumumab vedotin is an antibody‐drug conjugate that produced preliminary clinical activity against advanced melanoma in a phase 1 dose‐escalation trial. The objective of the current study was to investigate further the antitumor activity of glembatumumab vedotin at the recommended phase 2 dose in heavily pretreated patients with melanoma.MethodsThis single‐arm, phase 2 study enrolled patients with stage IV melanoma who were refractory to checkpoint inhibition and to B‐raf proto‐oncogene, serine/threonine kinase (BRAF)/mitogen‐activated protein kinase kinase (MEK) inhibition (in the presence of a BRAF valine mutation at codon 600). Patients received 1.9 mg/kg glembatumumab vedotin intravenously every 3 weeks until they developed disease progression or intolerance. The primary endpoint was objective response rate (ORR), which was determined according to Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary endpoints included progression‐free survival (PFS), duration of response, overall survival (OS), safety, and clinical efficacy versus tumor glycoprotein NMB (gpNMB) expression. Tumor expression of gpNMB was assessed using immunohistochemistry.ResultsIn total, 62 patients received treatment. The ORR was 11% and the median response duration was 6.0 months (95% confidence interval [CI], 4.1 months to not reached). The median PFS was 4.4 months (95% CI, 2.6‐5.5 months), and the median OS was 9.0 months (95% CI, 6.1‐11.7 months). For patients who developed rash during the first cycle versus those who did not, the ORR was 21% versus 7%, respectively, and there was an overall improvement in PFS (hazard ratio, 0.43; P = .013) and OS (hazard ratio, 0.43; P = .017). The most frequent adverse events were alopecia, neuropathy, rash, fatigue, and neutropenia. With one exception, all evaluable tumors were positive for gpNMB, and 46 of 59 tumors (76%) had 100% gpNMB‐positive epithelial cells.ConclusionsGlembatumumab vedotin had modest activity and an acceptable safety profile in patients with advanced melanoma who were refractory to checkpoint inhibitors and MEK/BRAF inhibition. Treatment‐related rash may be associated with response.
Meaningful differences and validity for the NCCN/FACT‐P Symptom Index: An analysis of the ALSYMPCA data
Authors: Beaumont Jennifer L. , Butt Zeeshan , Li Rui , Cella David 
Published: January 2019

BackgroundThe Functional Assessment of Cancer Therapy–Prostate (FACT‐P) and the National Comprehensive Cancer Network/Functional Assessment of Cancer Therapy–Prostate Symptom Index‐17 (NFPSI‐17) are 2 commonly used measures for patient‐reported outcomes in prostate cancer trials. Their use may be enhanced by a better understanding of how change scores on the measures should be interpreted.MethodsUsing data from the phase 3 Alpharadin in Symptomatic Prostate Cancer Patients trial, this study estimated important change scores on the FACT‐P and the NFPSI‐17 via a combination of distribution‐ and anchor‐based methods. These data were also used to establish evidence for the validity of the NFPSI‐17.ResultsThe available data suggested the following important difference ranges: 2 to 4 points for the Prostate Cancer Subscale, 5.5 to 8.5 points for the Trial Outcome Index, 1 to 1.5 points for the 3‐item Pain Scale, 1 to 2 points for the 4‐item Pain Scale, 4 to 6 points for the NFPSI‐17, 2 to 3.5 points for NFPSI–Disease‐Related Symptoms–Physical, 0.5 points for NFPSI–Disease‐Related Symptoms–Emotional, 1 to 1.5 points for NFPSI–Treatment Side Effects, and 0.5 to 1 point for NFPSI–Function/Well‐Being. The internal consistency reliability of the NFPSI‐17 and most of its subscales was good to excellent (>.70). Significant support was also found for the known groups validity of the NFPSI‐17 (and most of its subscales) on the basis of the Eastern Cooperative Oncology Group performance status, the total alkaline phosphatase, the presence of a skeletal‐related event during treatment, and the prostate‐specific antigen response before the end of treatment.ConclusionsThe secondary analysis supports the continued use of the FACT‐P, the NFPSI‐17, and its related subscales in future research on the quality of life of patients with symptomatic castration‐resistant prostate cancer with bone metastases.
Tumor dormancy in bone
Authors: Mayhew Vera , Omokehinde Tolu , Johnson Rachelle W. 
Published: January 2019

AbstractBackgroundBone marrow is a common site of metastasis for a number of tumor types, including breast, prostate, and lung cancer, but the mechanisms controlling tumor dormancy in bone are poorly understood. In breast cancer, while advances in drug development, screening practices, and surgical techniques have dramatically improved survival rates in recent decades, metastatic recurrence in the bone remains common and can develop years or decades after elimination of the primary tumor.Recent FindingsIt is now understood that tumor cells disseminate to distant metastatic sites at early stages of tumor progression, leaving cancer survivors at a high risk of recurrence. This review will discuss mechanisms of bone lesion development and current theories of how dormant cancer cells behave in bone, as well as a number of processes suspected to be involved in the maintenance of and exit from dormancy in the bone microenvironment.ConclusionsThe bone is a complex microenvironment with a multitude of cell types and processes. Many of these factors, including angiogenesis, immune surveillance, and hypoxia, are thought to regulate tumor cell entry and exit from dormancy in different bone marrow niches.
Possible Routes for Efficient Thermo‐Electric Energy Conversion in a Molecular Junction
Authors: Chakraborty Suvendu , Maiti Santanu K. 
Published: January 2019

AbstractIn the context of designing an efficient thermoelectric energy‐conversion device at nanoscale level, we suggest several important tuning parameters to enhance the performance of thermoelectric converters. We consider a simple molecular junction, which is always helpful to understand the basic mechanisms in a deeper way, where a benzene molecule is coupled to two external baths having unequal temperatures. The key component responsible for achieving better performance is associated with the asymmetric nature of transmission function, and in the present work, we show that it can be implemented in different ways by regulating the physical parameters involving the system. Employing a tight‐binding framework we calculate electrical and thermal conductances, thermopower, and figure of merit (FOM) by using Landauer integrals, and thoroughly examine the critical roles played by molecule‐to‐lead (ML) interface geometry, magnetic field, chemical substituent group, ML coupling, and the direct coupling between the two leads. Our results show that a reasonably large FOM (≫1) can be obtained and lead to a possibility of regulating the efficiency by selectively tuning the physical parameters. We believe that the present analysis will enhance the understanding of designing efficient thermoelectric devices, and can be verified in a laboratory.
Effect of Annealing on the Structural and Magnetic Properties of CoNiAl FSMA
Authors: Hossain Md. Sarowar , Ghosh Tanmoy , Kanth Bhoguju Rajini , Mukhopadhyay Pratip K. 
Published: January 2019

AbstractA ferromagnetic shape memory alloy is a very interesting system that has various structural transformation, microstructural phases and magnetic properties, and interplays among them. The system studied here is Co39Ni34Al27 that comprises a mixture of β (body‐centered cubic) and γ (face‐centered cubic) structural phases. Here the β phase is responsible for the FSMA behavior and the γ phase improves the mechanical properties necessary for practical applications. Herein, it is showed through resistivity and magnetization measurements that post‐annealing to a higher temperature significantly alters the ratio of β and γ phases in the system, resulting in increasing the austenite to martensite transition temperature and significantly modifying the magnetic properties. Additionally, it is also shown that the low‐temperature magnetic phase of this FSMA system is a disordered magnetic system.
Computational Approaches to Photoelectrode Design through Molecular Functionalization for Enhanced Photoelectrochemical Water Splitting
Authors: Iyer Ashwathi , Kearney Kara , Ertekin Elif 
Published: January 2019

AbstractPhotoelectrochemical water splitting is a promising carbon‐free approach to produce hydrogen from water. A photoelectrochemical cell consists of a semiconductor photoelectrode in contact with an aqueous electrolyte. Its performance is sensitive to properties of the photoelectrode/electrolyte interface, which may be tuned through functionalization of the photoelectrode surface with organic molecules. This can lead to improvements in the photoelectrode's properties. This Minireview summarizes key computational investigations on using molecular functionalization to modify photoelectrode stability, barrier height, and catalytic activity. It is discussed how first‐principles density functional theory, first‐principles molecular dynamics, and device modeling simulations can provide predictive insights and complement experimental investigations of functionalized photoelectrodes. Challenges and future directions in the computational modeling of functionalized photoelectrode/electrolyte interfaces within the context of experimental studies are also highlighted.
Electromodified NiFe Alloys as Electrocatalysts for Water Oxidation: Mechanistic Implications of Time‐Resolved UV/Vis Tracking of Oxidation State Changes
Authors: Loos Stefan , Zaharieva Ivelina , Chernev Petko , Lißner Andreas , Dau Holger 
Published: January 2019

AbstractFacile electromodification of metallic NiFe alloys leads to a series of NiFe oxyhydroxide surface films with excellent electrocatalytic performance in alkaline water oxidation. During cyclic voltammetry and after sudden potential jumps between noncatalytic and catalytic potentials, Ni oxidation/reduction was tracked with millisecond time resolution by a UV/Vis reflectance signal. Optimal catalysis at intermediate Ni/Fe ratios is explained by two opposing trends for increasing Fe content: a) pronounced slowdown of the Ni2+/Ni3+ oxidation step and b) increased reactivity of the most oxidized catalyst state detectable at catalytic potentials. This state may involve an equilibrium between Ni4+ ions and Ni2+ ions with neighboring ligand holes, possibly in the form of bound peroxides.
Bismuth Halide Perovskite‐Like Materials: Current Opportunities and Challenges
Authors: Zhang Long , Wang Kai , Zou Bo 
Published: January 2019

AbstractMetal halide perovskites have recently emerged as promising photovoltaic materials for application in solar cells with high power conversion efficiencies exceeding 23 %. In the years since such high efficiencies have been attained, investigations have mainly focused on the state‐of‐the‐art 3 D Pb‐based halide perovskite materials. However, the high toxicity of Pb and intrinsic instability of the pristine perovskite materials have become great obstacles to their industrial application and commercialization. To address these serious issues, it is imperative to explore low‐toxicity metal halide perovskites or their derivatives to substitute Pb‐based materials for better future development. Currently, Bi‐based halide perovskite‐like materials are attracting increased interest as environmentally friendly alternatives for photovoltaic applications. This Concept highlights recent advances of Bi‐based halide perovskite‐like materials in terms of understanding and modifying their fundamental properties and related device performance, with a focus on current challenges, opportunities for future development, and diversification of device applications.
Highly Selective and Pollution‐Free Electrochemical Extraction of Lithium by a Polyaniline/LixMn2O4 Cell
Authors: Zhao Along , Liu Jincheng , Ai Xinping , Yang Hanxi , Cao Yuliang 
Published: January 2019

AbstractConventional lithium extraction processes are inefficient or inadaptable for application in salt‐lake brines with high Mg/Li ratios of ≥6. A new electrochemical cell, polyaniline (PANI)/LixMn2O4, was proposed to solve this problem for selective recovery of Li+ ions from brine water with high impurity cations (K+, Na+, Mg2+, etc). Benefiting from the unique selectivity of spinel LixMn2O4 for Li+ insertion and the high capacity of the PANI polymer for Cl− doping, this PANI/LixMn2O4 cell could simultaneously extract LiCl from a simulated brine with a high average current efficiency of 95 %, an energy consumption of 3.95 W h molLiCl−1, and a strong cycle ability with 70.8 % capacity retention over 200 cycles. In particular, this method avoids the use of additional chemicals, offering a highly efficient, pollution‐free technology for Li+ extraction from brine waters.
Multispecies hierarchical modeling reveals variable responses of African carnivores to management alternatives
Authors: Farr Matthew T. , Green David S. , Holekamp Kay E. , Roloff Gary J. , Zipkin Elise F. 
Published: January 2019

AbstractCarnivore communities face unprecedented threats from humans. Yet, management regimes have variable effects on carnivores, where species may persist or decline in response to direct or indirect changes to the ecosystem. Using a hierarchical multispecies modeling approach, we examined the effects of alternative management regimes (i.e., active vs. passive enforcement of regulations) on carnivore abundances and group sizes at both species and community levels in the Masai Mara National Reserve, Kenya. Alternative management regimes have created a dichotomy in ecosystem conditions within the Reserve, where active enforcement of regulations maintains low levels of human disturbance in the Mara Triangle and passive enforcement of regulations in the Talek region permits multiple forms of human disturbance. Our results demonstrate that these alternative management regimes have variable effects on 11 observed carnivore species. As predicted, some species, such as African lions and bat‐eared foxes, have higher population densities in the Mara Triangle, where regulations are actively enforced. Yet, other species, including black‐backed jackals and spotted hyenas, have higher population densities in the Talek region where enforcement is passive. Multiple underlying mechanisms, including behavioral plasticity and competitive release, are likely causing higher black‐backed jackals and spotted hyena densities in the disturbed Talek region. Our multispecies modeling framework reveals that carnivores do not react to management regimes uniformly, shaping carnivore communities by differentially producing winning and losing species. Some carnivore species require active enforcement of regulations for effective conservation, while others more readily adapt (and in some instances thrive in response) to lax management enforcement and resulting anthropogenic disturbance. Yet, high levels of human disturbance appear to be negatively affecting the majority of carnivores, with potential consequences that may permeate throughout the rest of the ecosystem. Community approaches to monitoring carnivores should be adopted as single species monitoring may overlook important intra‐community variability.
Dung‐associated arthropods influence foraging ecology and habitat selection in Black‐necked Cranes (Grus nigricollis) on the Qinghai–Tibet Plateau
Authors: Liu Wei , Wu Yongjie , DuBay Shane G. , Zhao Chenhao , Wang Bin , Ran Jianghong 
Published: January 2019

AbstractVariation in grassland vegetation structure influences the habitat selection of insectivorous birds. This variation presents a trade‐off for insectivorous predators: Arthropod abundance increases with vegetation height and heterogeneity, but access to arthropod prey items decreases. In contrast, grazing by large herbivores reduces and homogenizes vegetation, decreasing total arthropod abundance and diversity. However, the presence of livestock dung may help counteract the overall reduction in invertebrates by increasing arthropods associated with dung. It is unclear, however, how the presence of arthropod prey in dung contributes to overall habitat selection for insectivorous birds or how dung‐associated arthropods affect trade‐offs between vegetation structure, arthropod abundance, and access to prey. To explore these relationships, we studied habitat selection of the Black‐necked Crane (Grus nigricollis), a large omnivorous bird that breeds on the Qinghai–Tibet Plateau. We assessed the relationships between habitat selection of cranes and vegetation structure, arthropod abundance, and the presence of yak dung. We found that Black‐necked Cranes disproportionately foraged in grassland patches with short sward height, low sward height heterogeneity, and high numbers of dry yak dung, despite these habitats having lower total arthropod abundance. Although total arthropod abundance is lower, these habitats are supplemented with dry yak dung, which are associated with coleopteran larvae, making dung pats an indicator of food resources for breeding Black‐necked Cranes. Coleopteran adults and larvae in yak dung appear to be an important factor influencing the habitat selection of Black‐necked Cranes and should be considered when assessing grassland foraging trade‐offs of insectivorous birds. This research provides new insights into the role of livestock dung in defining foraging habitats and resources for insectivorous predators.
Fitness costs associated with acetyl‐coenzyme A carboxylase mutations endowing herbicide resistance in American sloughgrass (Beckmannia syzigachne Steud.)
Authors: Du Long , Qu Mingjing , Jiang Xiaojing , Li Xiao , Ju Qian , Lu Xingtao , Wang Jinxin 
Published: January 2019

Abstract

Weed resistance to herbicide can be conferred by gene mutations, and some mutations can cause pleiotropic effects in some cases. We investigated the pleiotropic effects associated with five specific ACCase mutations (Ile1781Leu, Trp2027Cys, Ile2041Asn, Asp2078Gly, and Gly2096Ala) on the plant growth, seed production, and resource competitiveness in American sloughgrass.

Resistant plants (M/M) homozygous for specific ACCase mutation and susceptible wild‐type plants (W/W) were derived from single heterozygous mother plant (M/W) by genotyping. Plant growth assay and neighborhood experiments were performed to quantify variation between M/M plants and W/W plants.

The Ile1781Leu mutation resulted in slight increases in plant growth in pure stands and improved resource competitiveness under low‐competition conditions in pot experiments, but no clear variation was observed under high competitive pressure or field conditions. During competition with wheat plants under field conditions, American sloughgrass plants containing Ile2041Asn ACCase exhibited a significantly lower (12.5%) aboveground biomass but no distinct differences in seed production or resource competitiveness. No significant detrimental pleiotropic effects associated with Gly2096Ala were detected in American sloughgrass.

The Trp2027Cys mutation distinctly reduced seed production, especially under high competitive pressure, but did not significantly alter plant growth. The Asp2078Gly mutation consistently reduced not only plant growth and seed production but also resource competitiveness.

Synthesis. The Trp2027Cys and Asp2078Gly mutations led to significant fitness costs, which may reduce the frequency of resistance alleles and reduce the propagation speed of resistant weeds in the absence of ACCase inhibitor herbicides. The Ile1781Leu, Ile2041Asn, and Gly2096Ala mutations displayed no obvious fitness costs or displayed very small fitness penalties, which would likely have no effect on the establishment of resistant weeds in the field.