bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetic Analysis and Structural Interpretation of Competitive Ligand Binding for NO Dioxygenation in Truncated Hemoglobin N
Authors: Das Akshaya Kumar , Meuwly Markus 
Published: January 2018

AbstractThe conversion of nitric oxide (NO) into nitrate (NO3−) by dioxygenation protects cells from lethal NO. Starting from NO‐bound heme, the first step in converting NO into benign NO3− is the ligand exchange reaction FeNO+O2→FeO2+NO, which is still poorly understood at a molecular level. For wild‐type (WT) truncated hemoglobin N (trHbN) and its Y33A mutant, the calculated barriers for the exchange reaction differ by 1.5 kcal mol−1, compared with 1.7 kcal mol−1 from experiment. It is directly confirmed that the ligand exchange reaction is rate‐limiting in trHbN and that entropic contributions account for 75 % of the difference between the WT and the mutant. Residues Tyr 33, Phe 46, Val 80, His 81, and Gln 82 surrounding the active site are expected to control the reaction path. By comparison with electronic structure calculations, the transition state separating the two ligand‐bound states was assigned to a 2A state.
Effect of stereoisomerism of poly(lactic acid) during neural guide conduit membrane synthesis
Authors: Domingues Rui Carlos Castro , Pereira Cristina Cardoso , Borges Cristiano Piacsek 
Published: January 2018

ABSTRACTPoly(lactic acid) membranes are being developed as biomaterials for several purposes such as artificial implants for peripheral nerve injury, also known as neural guide conduits (NGC). These membranes need to meet standards of mechanical, degradability, and permeability properties, besides dimensional and structural requirements. Among the stereoisomers of polylactides, poly(l‐lactic acid), and poly(d,l‐lactic acid) are the most used as biomaterials, having significant differences in solubility, crystallinity thermal, and mechanical properties. In this work, PLLA and PDLLA were compared for hollow fiber membrane synthesis by liquid induced phase separation. PLLA samples presented 18% of crystallinity, while PDLLA is amorphous. PDLLA and PLLA polymer solutions on N‐methyl‐pyrrolidone presented values of 3428 and 320.2 cP, respectively. In immersion of PLA‐NMP solutions in water, PLLA solution presented instantaneous demixing, while PDLLA showed a 28 s delay on precipitation. The PLLA–NMP–water has a larger demixing region compared to PDLLA–NMP–water system. Hollow fibers of both polymers presented closed external surface with finger‐like macropores morphology in their cross‐sections. PDLLA presented typical liquid–liquid demixing pores while PLLA presented spherulitical crystalline solid–liquid separation structures, which deeply compromised its mechanical properties. PDLLA presented as a good candidate for hollow fiber NGC material, as presented good mechanical resistance in tensile and suture simulating tests. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46190.
[(18‐Crown‐6)K][Fe(1)Cl(1)4]0.5[Fe(2)Cl(2)4]0.5: A Multifunctional Molecular Switch of Dielectric, Conductivity and Magnetic Properties
Authors: Tong Yuan‐Bo , Tian Zheng‐Fang , Duan Hai‐Bao , Zhu Zhong‐Peng , He Wei , Hong Tian‐Yu , Yu Gui , He Yu‐Jian , Yang Jing‐Kui 
Published: January 2018

AbstractMultifunctional materials that exhibit different physical properties in a single phase have potential for use in multifunctional devices. Herein, we reported an organic–inorganic hybrid compound [(18‐crown‐6)K][Fe(1)Cl(1)4]0.5[Fe(2)Cl(2)4]0.5 (1) by incorporating KCl and FeCl3 into a 18‐crown‐6 molecule, which acts as a host of the six O atoms providing a lone pair of electrons to anchor the guest potassium cation, and [FeCl4]− as a counterion for charge balance to construct a complex salt. This salt exhibited a one‐step reversible structural transformation giving two separate high and low temperature phases at 373 K, which was confirmed by systematic characterizations including differential scanning calorimetry (DSC) measurements, variable‐temperature structural analyses, and dielectric, impedance, variable‐temperature magnetic susceptibility measurements. Interestingly, the structural transformation was coupled to both hysteretic dielectric phase transition, conductivity switch and magnetic‐phase transition at 373 K. This result gives an idea for designing a new type of phase‐transition materials harboring technologically important magnetic, conductivity and dielectric properties.
Accurate determination of a novel vasodilatory β‐blocker TJ0711 using LC‐MS/MS: Resolution of an isobaric metabolite interference in dog plasma
Authors: Hu Yang , Zhu Wenwen , Guan Yeli , Wu Sanlan , Zhang Xiaoyin , Li Gao , Si Luqin , Huang Jiangeng 
Published: January 2018

AbstractA rapid, robust and sensitive liquid chromatography–tandem mass spectrometry method was developed and validated for bioanalysis of TJ0711, a novel vasodilatory β‐blocker in dog plasma. This assay is able to chromatographically separate TJ0711 from its isobaric metabolite as well as glucuronide conjugates. Chromatographic separation was achieved on a Welch Ultimate‐XB C18 column (2.1 × 100 mm, 3 μm). The analyte and internal standard (propranolol) were extracted from plasma by liquid–liquid extraction using ethyl acetate. The mass spectrometric detection was carried out in positive ion multiple reaction monitoring mode. Good linearity was obtained over the concentration range of 0.5–500 ng/mL (r > 0.99) for TJ0711. Moreover, the method had good accuracy (RE ranging from −2.70 to −0.32%) and precision (RSD < 7.55%). TJ0711 was stable in dog plasma for at least 6 h at ambient temperature, for at least 30 days at −20°C and after three freeze–thaw cycles. This method was successfully applied to a preclinical pharmacokinetic study and the results demonstrated linear pharmacokinetics of TJ0711 over a dose range from 0.03 to 0.3 mg/kg. No significant gender differences were observed in TJ0711 plasma pharmacokinetic parameters.
Six New Polyhydroxysteroidal Glycosides, Anthenosides S1 – S6, from the Starfish Anthenea sibogae
Authors: Kicha Alla A. , Ha Dinh T. , Ivanchina Natalia V. , Malyarenko Timofey V. , Kalinovsky Anatoly I. , Dmitrenok Pavel S. , Ermakova Svetlana P. , Malyarenko Olesya S. , Hung Nguyen A. , Thuy Tran T. T. , Long Pham Q. 
Published: January 2018

Six new polyhydroxysteroidal glycosides, anthenosides S1 – S6 (1 – 6), along with a mixture of two previously known related glycosides, 7 and 8, were isolated from the methanolic extract of the starfish Anthenea sibogae. The structures of 1 – 6 were established by NMR and HR‐ESI‐MS techniques as well as by chemical transformations. All new compounds have a 5α‐cholest‐8(14)‐ene‐3α,6β,7β,16α‐tetrahydroxysteroidal nucleus and differ from majority of starfish glycosides in positions of carbohydrate moieties at C(7) and C(16) (1 – 4, 6) or only at C(16) (5). The 4‐O‐methyl‐β‐d‐glucopyranose residue (2) and Δ24‐cholestane side chain (3) have not been found earlier in the starfish steroidal glycosides. The mixture of 7 and 8 slightly inhibited the proliferation of human breast cancer T‐47D cells and decreased the colony size in the colony formation assay.
A Modular Nanoswitch for Mix‐and‐Detect Protein Assay Based on Binding‐Induced Cascade Dissociation of Kissing Complex
Authors: Tian Yishen , Zhang Shanshan , Wang Li , Liu Shufeng 
Published: January 2018

AbstractA new modular nanoswitch was described for versatile, rapid (within 1 h), homogeneous, and sensitive protein detection. The system employs two hairpins (HP1 and HP2) that can be reciprocally recognized through the apical loop–loop interaction. HP2 possesses a conformation‐switching stem–loop structure, with appended single‐stranded tails on each end, which can hybridize with the recognition‐element‐conjugated DNA strands to construct a protein‐responsive HP2 scaffold. It works according to a simple mix‐and‐detect assay format, with the first formation of a kissing complex between HP1 and HP2 scaffolds for fluorescence quenching, and then cascade propagation from steric strain through protein binding to the dissociation of the kissing complex for fluorescence recovery. The detection universality of such a modular nanoswitch was demonstrated by using three multivalent proteins, including anti‐digoxigenin (Anti‐Dig) antibody, streptavidin, and thrombin, with detection limits of 0.33, 0.17, and 0.5 nm, respectively.
Antiplatelet drug selection in PCI to vein grafts in patients with acute coronary syndrome and adverse clinical outcomes: Insights from the British Cardiovascular Intervention Society database
Authors: Sirker Alex , Kwok Chun Shing , Kontopantelis Evangelos , Johnson Tom , Freeman Philip , de Belder Mark A , Ludman Peter , Zaman Azfar , Mamas Mamas A 
Published: January 2018

AbstractObjectiveThis study aims to evaluate outcomes associated with different P2Y12 agents in Saphenous Vein graft (SVG) percutaneous coronary intervention (PCI).BackgroundSVG PCI is associated with greater risks of ischemic complications, compared with native coronary PCI. Outcomes associated with the use of potent P2Y12 blocking drugs, Prasugrel and Ticagrelor, in SVG PCI are unknown.MethodsPatients included in the study underwent SVG PCI in the United Kingdom between 2007 and 2014 for acute coronary syndrome and were grouped by P2Y12 antiplatelet use. In‐hospital major adverse cardiac events, major bleeding and 30‐day and 1‐year mortality were examined. Multiple imputations with chained equations to impute missing data were used. Adjustment for baseline imbalances was performed using (1) multiple logistic regression (MLR) and (separately) (2) propensity score matching (PSM).ResultsData weres analyzed from 8,119 patients and most cases were treated with Clopidogrel (n = 7,401), followed by Ticagrelor (n = 497) and Prasugrel (n = 221). In both MLR and PSM models, there was no significant evidence to suggest that either Prasugrel or Ticagrelor was associated with significantly lower 30‐day mortality compared with Clopidogrel. The odds ratios reported from the multivariable analysis were 1.22 (95% CI: 0.60–2.51) for Prasugrel vs. Clopidogrel and 0.48 (95% CI: 0.20–1.16) for Ticagrelor vs. Clopidogrel. No significant differences were seen for in‐hospital ischemic or bleeding events.ConclusionsOur real world national study provides no clear evidence to indicate that use of potent P2Y12 blockers in SVG PCI is associated with improved clinical outcomes.
Effects of parboiling and other hydrothermal treatments on the physical, functional, and nutritional properties of rice and other cereals
Authors: Rocha‐Villarreal Verónica , Serna‐Saldivar Sergio O. , García‐Lara Silverio 
Published: January 2018

Background and objectivesParboiling is a hydrothermal treatment, rarely used in cereals other than rice, which consists in three sequential steps: grain conditioning or soaking, cooking, and drying. The aim of this process was to partially gelatinize the starch to seal fissures/cracks and therefore improve milling yield. This review aims to discuss the reported effects of parboiling and similar hydrothermal treatments on the physicochemical, nutritional, processing, and storage properties of rice but mostly of other cereals.FindingsIndependently of the type of cereal, parboiling leads to changes in physicochemical, nutritional, and technological properties. However, the standardization and commercial scaling of these processes have been limited.ConclusionsThe parboiling effect varies according to the grain intrinsic properties and the processing conditions. Some cereals behave similar to rice, but others are affected oppositely. Further research is needed to better understand the effects of parboiling and hydrothermal treatments in cereal grains, and for the development of a standardized methodology for hydrothermally treating grains.Significance and noveltyThe understanding of the effects and the proper implementation of these hydrothermal treatments in corn could lead to significant enhancements in grains properties that could play a key role to solve hunger, malnutrition, and related food security problems.
Characterizing whole‐wheat flours produced using a commercial stone mill, laboratory mills, and household single‐stream flour mills
Authors: Ross Andrew S. , Kongraksawech Teepakorn 
Published: January 2018

Background and objectivesOne hard wheat and one semi‐hard wheat were milled on commercial, laboratory, and household‐scale flour mills with rotating elements ranging from 0.1 to 1.0 m in diameter and speeds ranging from 65 to 40,000 rpm. The aim of the study was to assess and compare the quality of the flour from each of mills.FindingsPasting viscosities, Farinograph development time and stability, and loaf volumes (LVOL) were all markedly influenced by whole‐wheat flour particle size, which differed markedly between mills. LVOLs were acceptable using the flours produced by all the mills. Best flour quality came from the three mills that produced the finest whole‐wheat flour. Of these, the superior flour came from the 1.0‐m‐diameter Osttiroler stone mill. This mill produced whole‐wheat flours with more optimal levels of starch damage and higher water absorption than did the smaller mills. There was no evidence of degradation of gluten functionality even at a flour temperature of 51°C.ConclusionsThe mill used affected almost all flour quality traits. However, the characteristics of the wheat applied to the mill were the dominant influence on flour functionality. Starch damage may better indicate milling severity than the heat generated during the milling process.Significance and noveltyThis is the only study, that we know of, on the comparative performance of household‐scale flour mills. The study also presents an alternative way of visualizing particle size distributions of flours.
Factors affecting Asian wheat noodle color and time‐dependent discoloration—A review
Authors: Siah Siem , Quail Kenneth J. 
Published: January 2018

Background and objectivesWheat noodles are a staple food for many Asian populations, particularly in East and South‐East Asian countries. Fresh noodles are subject to discoloration or darkening over storage time if not cooked or preserved. The physical appearance of noodles has the very first and often most significant impact on consumer perception leading to purchasing decisions. This review paper outlines the different noodle types followed by discussing factors affecting noodle color and time‐dependent discoloration. Methods used for preserving noodle freshness and color are also discussed.FindingsWheat noodles are generally categorized as white salted noodles made with the addition of sodium chloride, and yellow alkaline noodles made with the addition of different combinations of sodium chloride and alkaline salts. The intrinsic factors relating to wheat and flour quality affecting noodle color and discoloration include protein content, wheat bran color, falling number and preharvest sprouting, ash content, polyphenol oxidase, carotenoids, phenolic compounds, and flour color. The extrinsic factors relating to processing parameters affecting noodle color and time‐dependent discoloration include selection of flour mill streams, flour milling extraction rates, starch damage, noodle processing methods, addition of different salt types, addition of eggs, gluten, starch and emulsifiers, water addition and absorption levels, and addition of plant materials.ConclusionsIt is important for manufacturers to select the right wheat type, processing methods, and formulation to produce noodles with desirable color appearance and less susceptible to time‐dependent discoloration.Significance and noveltyThis review paper details intrinsic factors relating to wheat and flour quality, and extrinsic factors relating to processing parameters that affect wheat noodle color and time‐dependent discoloration.
Recent Advances in Germanium‐Based Photoinitiator Chemistry
Authors: Haas Michael , Radebner Judith , Eibel Anna , Gescheidt Georg , Stueger Harald 
Published: January 2018

AbstractAcylgermanes provide an outstanding photoinduced reactivity at very useful absorption wavelengths. This encouraged multidisciplinary research groups to utilize them as highly effective and non‐toxic photoinitiators particularly for medical applications. In this Minireview, we present the most recent breakthroughs to synthesize acylgermanes. We also outline mechanistic aspects of photoinduced reactions of several acylgermane derivatives based on fundamental spectroscopic insights. These studies may aid future developments for tailor‐made photoinitiators.
Copper‐Catalyzed Aziridination with Redox‐Active Ligands: Molecular Spin Catalysis
Authors: Ren Yufeng , Cheaib Khaled , Jacquet Jérémy , Vezin Hervé , Fensterbank Louis , Orio Maylis , Blanchard Sébastien , Desage‐El Murr Marine 
Published: January 2018

AbstractSmall‐molecule catalysts as mimics of biological systems illustrate the chemists’ attempts at emulating the tantalizing abilities displayed by nature's metalloenzymes. Among these innate behaviors, spin multistate reactivity is used by biological systems as it offers thermodynamic leverage towards challenging chemical reactivity but this concept is difficult to translate into the realm of synthetic organometallic catalysis. Here, we report a rare example of molecular spin catalysis involving multistate reactivity in a small‐molecule biomimetic copper catalyst applied to aziridination. This behavior is supported by spin state flexibility enabled by the redox‐active ligand.
Crystal Field in Rare‐Earth Complexes: From Electrostatics to Bonding
Authors: Alessandri Riccardo , Zulfikri Habiburrahman , Autschbach Jochen , Bolvin Hélène 
Published: January 2018

AbstractThe flexibility of first‐principles (ab initio) calculations with the SO‐CASSCF (complete active space self‐consistent field theory with a treatment of the spin‐orbit (SO) coupling by state interaction) method is used to quantify the electrostatic and covalent contributions to crystal field parameters. Two types of systems are chosen for illustration: 1) The ionic and experimentally well‐characterized PrCl3 crystal; this study permits a revisitation of the partition of contributions proposed in the early days of crystal field theory; and 2) a series of sandwich molecules [Ln(ηn‐CnHn)2]q, with Ln=Dy, Ho, Er, and Tm and n=5, 6, and 8, in which the interaction between LnIII and the aromatic ligands is more difficult to describe within an electrostatic approach. It is shown that a model with three layers of charges reproduces the electrostatic field generated by the ligands and that the covalency plays a qualitative role. The one‐electron character of crystal field theory is discussed and shown to be valuable, although it is not completely quantitative. This permits a reduction of the many‐electron problem to a discussion of the energy of the seven 4f orbitals.
Phenylboronic Acid Derivatives as Validated Leads Active in Clinical Strains Overexpressing KPC‐2: A Step against Bacterial Resistance
Authors: Celenza Giuseppe , Vicario Mattia , Bellio Pierangelo , Linciano Pasquale , Perilli Mariagrazia , Oliver Antonio , Blazquez Jesús , Cendron Laura , Tondi Donatella 
Published: January 2018

AbstractThe emergence and dissemination of multidrug resistant (MDR) pathogens resistant to nearly all available antibiotics poses a significant threat in clinical therapy. Among them, Klebsiella pneumoniae clinical isolates overexpressing KPC‐2 carbapenemase are the most worrisome, extending bacterial resistance to last‐resort carbapenems. In this study, we investigate the molecular recognition requirements in the KPC‐2 active site by small phenylboronic acid derivatives. Four new phenylboronic acid derivatives were designed and tested against KPC‐2. For the most active, despite their simple chemical structures, nanomolar affinity was achieved. The new derivatives restored susceptibility to meropenem in clinical strains overexpressing KPC‐2. Moreover, no cytotoxicity was detected in cell‐viability assays, which further validated the designed leads. Two crystallographic binary complexes of the best inhibitors binding KPC‐2 were obtained at high resolution. Kinetic descriptions of slow binding, time‐dependent inhibition, and interaction geometries in KPC‐2 were fully investigated. This study will ultimately lead toward the optimization and development of more‐effective KPC‐2 inhibitors.
Essential role of hippocampal noradrenaline in the regulation of spatial working memory and TDP‐43 tissue pathology
Authors: Pintus Roberta , Riggi Margherita , Cannarozzo Cecilia , Valeri Andrea , de Leo Gioacchino , Romano Maurizio , Gulino Rosario , Leanza Giampiero 
Published: January 2018

AbstractExtensive loss of noradrenaline‐containing neurons and fibers is a nearly invariant feature of Alzheimer's Disease (AD). However, the exact noradrenergic contribution to cognitive and histopathological changes in AD is still unclear. Here, this issue was addressed following selective lesioning and intrahippocampal implantation of embryonic noradrenergic progenitors in developing rats. Starting from about 3 months and up to 12 months post‐surgery, animals underwent behavioral tests to evaluate sensory‐motor, as well as spatial learning and memory, followed by post‐mortem morphometric analyses. At 9 months, Control, Lesioned and Lesion + Transplant animals exhibited equally efficient sensory‐motor and reference memory performance. Interestingly, working memory abilities were seen severely impaired in Lesion‐only rats and fully recovered in Transplanted rats, and appeared partly lost again 2 months after ablation of the implanted neuroblasts. Morphological analyses confirmed the almost total lesion‐induced noradrenergic neuronal and terminal fiber loss, the near‐normal reinnervation of the hippocampus promoted by the transplants, and its complete removal by the second lesion. Notably, the noradrenergic‐rich transplants normalized also the nuclear expression of the transactive response DNA‐binding protein 43 (TDP‐43) in various hippocampal subregions, whose cytoplasmic (i.e., pathological) occurrence appeared dramatically increased as a result of the lesions. Thus, integrity of ascending noradrenergic inputs to the hippocampus may be required for the regulation of specific aspects of learning and memory and to prevent TDP‐43 tissue pathology.
Application of the Interacting Quantum Atoms Approach to the S66 and Ionic‐Hydrogen‐Bond Datasets for Noncovalent Interactions
Authors: Suárez Dimas , Díaz Natalia , Francisco Evelio , Martín Pendás Angel 
Published: January 2018

AbstractThe interacting quantum atoms (IQA) method can assess, systematically and in great detail, the strength and physics of both covalent and noncovalent interactions. The lack of a pair density in density functional theory (DFT), which precludes the direct IQA decomposition of the characteristic exchange–correlation energy, has been recently overcome by means of a scaling technique, which can largely expand the applicability of the method. To better assess the utility of the augmented IQA methodology to derive quantum chemical decompositions at the atomic and molecular levels, we report the results of Hartree–Fock (HF) and DFT calculations on the complexes included in the S66 and the ionic H‐bond databases of benchmark geometry and binding energies. For all structures, we perform single‐point and geometry optimizations using HF and selected DFT methods with triple‐ζ basis sets followed by full IQA calculations. Pairwise dispersion energies are accounted for by the D3 method. We analyze the goodness of the HF‐D3 and DFT‐D3 binding energies, the magnitude of numerical errors, the fragment and atomic distribution of formation energies, etc. It is shown that fragment‐based IQA decomposes the formation energies in comparable terms to those of perturbative approaches and that the atomic IQA energies hold the promise of rigorously quantifying atomic and group energy contributions in larger biomolecular systems.