bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drug Screening in Human Cells by NMR Spectroscopy Allows the Early Assessment of Drug Potency
Authors: Luchinat Enrico , Barbieri Letizia , Cremonini Matteo , Nocentini Alessio , Supuran Claudiu T. , Banci Lucia 
Published: February 2020

AbstractStructure‐based drug development is often hampered by the lack of in vivo activity of promising compounds screened in vitro, due to low membrane permeability or poor intracellular binding selectivity. Herein, we show that ligand screening can be performed in living human cells by “intracellular protein‐observed” NMR spectroscopy, without requiring enzymatic activity measurements or other cellular assays. Quantitative binding information is obtained by fast, inexpensive 1H NMR experiments, providing intracellular dose‐ and time‐dependent ligand binding curves, from which kinetic and thermodynamic parameters linked to cell permeability and binding affinity and selectivity are obtained. The approach was applied to carbonic anhydrase and, in principle, can be extended to any NMR‐observable intracellular target. The results obtained are directly related to the potency of candidate drugs, that is, the required dose. The application of this approach at an early stage of the drug design pipeline could greatly increase the low success rate of modern drug development.
Enhancing Hydrogen Evolution Activity of Au(111) in Alkaline Media through Molecular Engineering of a 2D Polymer
Authors: Alexa Patrick , Lombardi Juan Manuel , Abufager Paula , Busnengo Heriberto Fabio , Grumelli Doris , Vyas Vijay S. , Haase Frederik , Lotsch Bettina V. , Gutzler Rico , Kern Klaus 
Published: February 2020

AbstractThe electrochemical splitting of water holds promise for the storage of energy produced intermittently by renewable energy sources. The evolution of hydrogen currently relies on the use of platinum as a catalyst—which is scarce and expensive—and ongoing research is focused towards finding cheaper alternatives. In this context, 2D polymers grown as single layers on surfaces have emerged as porous materials with tunable chemical and electronic structures that can be used for improving the catalytic activity of metal surfaces. Here, we use designed organic molecules to fabricate covalent 2D architectures by an Ullmann‐type coupling reaction on Au(111). The polymer‐patterned gold electrode exhibits a hydrogen evolution reaction activity up to three times higher than that of bare gold. Through rational design of the polymer on the molecular level we engineered hydrogen evolution activity by an approach that can be easily extended to other electrocatalytic reactions.
Viscometric Properties of Polyethylene Glycol di‐Esters of Estolides
Authors: Isbell Terry A. , Lowery Benjamin A. , Cermak Steven C. 
Published: February 2020

AbstractPolyethylene glycol (PEG) diesters from estolides of oleic acid, ricinoleic acid, and 12‐hydroxy stearic acid were used up to 5 wt% additive in petroleum‐derived base oils: 100 N, 220 N, 600 N, PAO 2cSt, PAO 4cst, and PAO 8cSt. The viscosity indices of the petroleum base oils were the lowest (VI = 104–108); the polyalpholefin (PAO) synthetic petroleum‐derived base oils were better (VI = 124–136) and the vegetable‐derived oils were the best (VI = 111–205). 12‐Hydroxystearic estolide PEG 400 diester gave the largest increase in viscosity index in 5% w/w admixtures with PAO 2cSt, 4cSt, 220 N, and 600 N base oils with a 12.3–16.3% increase in viscosity index. Single fatty chain esters had the least impact on viscosity index. As the molecule bulk increased, the viscosity index also increased. This viscosity index effect was demonstrated for the series of monomer to oleic estolide to oleic estolide PEG‐200 diester, which gave viscosity indices of 110, 111–122, respectively, in 5% admixtures with 100 N base oil. The larger the size of the molecule coupled with the polar PEG moiety gave the largest impact on viscosity index improvement where a 5 wt% admixture of 12‐hydroxystearate estolide PEG‐200 diester gave a 25.8% increase in 100 °C viscosity in PAO 2cSt. Incorporation of a dihydroxyl moiety into the molecule at a central side chain location in laurate‐capped ricinoleate estolide PEG‐200 diester did not increase viscosity index of the base oil but greatly reduced its solubility to less than 0.5 wt%.
Strategies to Control Hypervalent Iodine – Primary Amine Reactions
Authors: Bal Ankita , Maiti Saikat , Mal Prasenjit 
Published: February 2020

AbstractThe field of hypervalent iodine chemistry has been prevalent since 1886. Its journey from obscurity to coming into the limelight has witnessed many effective transformations which have benefited the synthetic community at large. The reactivity of primary amines with hypervalent iodine reagents causes difficulty in synthetic outcome or not feasible due to high exothermicity of amine iodine which is an acid base reaction. This minireview highlights the worthwhile reactivity of hypervalent iodine reagents with aromatic and aliphatic primary amines. Some recent literature has been discussed to make a clear understanding on how such high reactivity of primary amine is controlled by introducing modulation in either substrate or reaction conditions, most of which are carried out under ambient reaction conditions.
Alkaline Earth Metal‐Mediated Highly Iso‐selective Ring‐Opening Polymerization of rac‐Lactide
Authors: Bhattacharjee Jayeeta , Harinath Adimulam , Sarkar Alok , Panda Tarun K. 
Published: February 2020

AbstractAlkaline earth (Ae) metal complexes of the aminophosphine borane ligand are highly active and iso‐selective catalysts for the ring‐opening polymerization (ROP) of rac‐lactide (LA). The polymerization reactions are well controlled and produce polylactides with molecular weights that are precise and narrowly distributed. Kinetic studies reveal that the ROP of rac‐LA catalyzed by all Ae metal complexes had a first‐order dependency on LA concentration as well as catalyst concentration. A plausible reaction mechanism for Ae metal complex‐mediated ROP of rac‐LA is discussed, based on controlled kinetic experiments and molecular chain mobility.
Crystal Structures of Dimethoxyanthracens: A Clue to a Rational Design of Packing Structures of π‐Conjugated Molecules
Authors: Takimiya Kazuo , Ogaki Takuya , Wang Chengyuan , Kawabata Kohsuke 
Published: February 2020

AbstractWe carried out a systematic investigation of packing structures of a series of dimethoxyanthracenes, i. e., 1,4‐ (1), 1,8‐ (2), 1,5‐ (3), 2,6‐ (4), and 2,7‐derivatives (5). The packing structures of the dimethoxyanthracenes are classified into two types, a rubrene‐like pitched π‐stack (1–3) and a typical herringbone packing (4 and 5), which evidently show that the position of methoxy groups is crucial to determine the packing structure of dimethoxyanthracenes. Effects of the substitution position on intermolecular interactions are analyzed by the noncovalent intermolecular interaction (NCI) method, Hirshfeld surface analysis, and symmetry‐adapted perturbation theory (SAPT) method, thus clarifying active roles of the methoxy groups in the formation of rubrene‐like pitched π‐stack. The present results shed light on a molecular design strategy to realize the rubrene‐like pitched π‐stack in the solid state, which had been regarded as a packing structure limited for rubrene and its closely related derivatives.
Interlayer Engineering of MnO2 with High Charge Density Bi3+ for High Rate and Stable Aqueous Supercapacitor
Authors: Xiong Ting , Zhu Mingke , Zhang Yaoxin , Lee Wee Siang Vincent , Yu Zhi Gen , Xue Junmin 
Published: February 2020

AbstractTwo‐dimensional δ‐MnO2 has attracted considerable attention as supercapacitor electrode due to its ability to incorporate foreign ions into its interlayer spacing which suggests the possibility of capacitance enhancement through interlayer engineering. Incorporating high charge density cation such as Bi3+ into the MnO2 interlayer becomes an attractive strategy that not only serves to stabilize the layer structure, it is also an important prelude towards the weakening of the chemical bonding between the O from MnO2 and the intercalating electrolyte species. This in turn leads to higher reversibility while ensuring excellent structural stability that is portrayed in enhanced cyclic stability and rate performance. Herein, the Bi3+‐modified δ‐MnO2 delivered a reversible specific capacity of 421 F g−1 at 1 A g−1, which is higher than that of the previously reported mono/divalent cation‐intercalant modified MnO2 systems. Using the N‐doped carbon nanosheets as the negative electrode, the assembled asymmetric supercapacitor achieved a high capacitance of 77 F g−1 at 1 Ag−1. Furthermore, the high energy density of 20 Wh kg−1 was recorded at a high‐power density of 39 kW kg−1, while simultaneously demonstrating excellent cycle performance of 82 % capacitance retention after 40 000 cycles. This work has shown that interlayer engineering of layered MnO2 could potentially provide new insight into the development of high‐performance supercapacitor electrode.
Joint analysis of panel count and interval‐censored data using distribution‐free frailty analysis
Authors: Wen Chi‐Chung , Chen Yi‐Hau , Tseng Chi‐Hong 
Published: February 2020

AbstractWe propose a joint analysis of recurrent and nonrecurrent event data subject to general types of interval censoring. The proposed analysis allows for general semiparametric models, including the Box–Cox transformation and inverse Box–Cox transformation models for the recurrent and nonrecurrent events, respectively. A frailty variable is used to account for the potential dependence between the recurrent and nonrecurrent event processes, while leaving the distribution of the frailty unspecified. We apply the pseudolikelihood for interval‐censored recurrent event data, usually termed as panel count data, and the sufficient likelihood for interval‐censored nonrecurrent event data by conditioning on the sufficient statistic for the frailty and using the working assumption of independence over examination times. Large sample theory and a computation procedure for the proposed analysis are established. We illustrate the proposed methodology by a joint analysis of the numbers of occurrences of basal cell carcinoma over time and time to the first recurrence of squamous cell carcinoma based on a skin cancer dataset, as well as a joint analysis of the numbers of adverse events and time to premature withdrawal from study medication based on a scleroderma lung disease dataset.
Use of eosin for green spectroscopic determination of mebendazole
Authors: Roshdy Aya , Elmansi Heba , Shalan Shereen , Elbrashy Amina 
Published: February 2020

AbstractNew, sensitive, and reliable spectroscopic methods were constructed for the fast determination of the anthelmintic drug mebendazole. The methods depended on the reaction of the amino group in mebendazole with eosin in acidic medium forming an ion pair complex. The first method, Method I, relied on quenching of the native fluorescence of eosin after reaction with mebendazole at pH 3.7 using acetate buffer. Fluorescence quenching was measured at 538 nm after excitation at 518 nm. This method showed a linear response over the concentration range 5.0–20.0 μg/ml. The second method, Method II, was based on measuring the absorbance of the formed complex at 554 nm; the method showed good linearity from 7.0 to 22.0 μg/ml. Different parameters that influenced the formation of the reaction product were carefully investigated to reach the optimized conditions. A comparison between the proposed methods and a previous spectrophotometric method was carried out and there was no significant difference between them. The methods could be applied successfully to determine mebendazole in its tablet form. Moreover, the methods used water as diluting solvent, which made them compatible with the ‘green’ analytical chemistry principles. No organic solvents were used throughout the study.
Retracted: MicroRNA‐31 weakens cisplatin resistance of medulloblastoma cells via NF‐κB and PI3K/AKT pathways
Authors: Ma Hui , Cao Wei , Ding Meili 
Published: February 2020

AbstractBackgroundMedulloblastoma (MB) is a malignant intracranial tumor. Cisplatin is a broad‐spectrum antitumor drug. It is important to study the cisplatin resistance of MB cells for the treatment of MB. In this article, we preliminarily studied the cisplatin resistance of microRNA (miR)‐31 and the possible mechanism in DAOY and UW228 cells, laying a theoretical foundation for clinical treatment of MB.MethodsFollowing anti‐miR‐31 and pre‐miR‐31 transfections, cell viability, BrdU, CyclinD1, and apoptosis levels of DAOY and UW228 cell were detected by CCK8, BrdU, and western blot. Meanwhile, migration, invasion, and western blot assay were respectively used to detect the functions of miR‐31 migration and invasion. miR‐31 levels were changed by cell transfection and detected by RT‐qPCR. Furthermore, the related‐proteins of pathways were also detected by western blot.ResultsAnti‐miR‐31 increased DAOY and UW228 cells viability, BrdU+ numbers, and expression of CyclinD1. The migration/invasion rate and expression levels of MMP‐9 and vimentin after anti‐miR‐31 transfection were increased. Furthermore, anti‐miR‐31 enhanced cells' cisplatin resistance and triggered PI3K/AKT and NF‐κB pathways. Pre‐miR‐31 played opposite roles and promoted the apoptosis.ConclusionmiR‐31 regulated cell growth, migration, invasion and cisplatin resistance of MB cells via PI3K/AKT and NF‐κB pathways.
Predictive immunohistochemical features for tumour response to chemoradiotherapy in rectal cancer
Authors: Shinto E , Omata J , Sikina A , Sekizawa A , Kajiwara Y , Hayashi K , Hashiguchi Y , Hase K , Ueno H 
Published: February 2020

Abstract

Background
Reduced expression of cluster of differentiation (CD) 133 and cyclo-oxygenase (COX) 2, and increased density of CD8+ tumour-infiltrating lymphocytes, are associated with a favourable tumour response to preoperative chemoradiotherapy (CRT). This study aimed to evaluate these markers in relation to tumour response after preoperative CRT in two rectal cancer cohorts.

Methods
Patients with low rectal cancer who underwent radical resection and preoperative short-term CRT in 2001–2007 (retrospective cohort) and long-term CRT in 2011–2017 (prospective cohort) were analysed. Pretreatment biopsies were stained immunohistochemically using antibodies to determine CD133 and COX-2 expression, and increased CD8+ density. Outcome measures were tumour regression grade (TRG), tumour downstaging and survival.

Results
For 95 patients in the retrospective cohort, the incidence of TRG 3–4 was 67 per cent when two or three immunohistochemistry (IHC) features were present, but only 20 per cent when there were fewer features (P &lt; 0·001). The incidence of tumour downstaging was higher in patients with at least two IHC features (43 versus 22 per cent with fewer features; P = 0·029). The 49 patients in the prospective cohort had similar rates to those in the retrospective cohort (TRG 3–4: 76 per cent for two or more IHC features versus 25 per cent with fewer features, P &lt; 0·001; tumour downstaging: 57 versus 25 per cent respectively, P = 0·022). Local recurrence-free survival rates in patients with more or fewer IHC features were similar in the retrospective and prospective cohort (P = 0·058 and P = 0·387 respectively).

Conclusion
Assessment of CD133, COX-2 and CD8 could be useful in predicting a good response to preoperative CRT in patients with lower rectal cancer undergoing neoadjuvant therapy. Further studies are needed to validate the results in larger cohorts and investigate a survival benefit.
Gene polymorphisms and motor levodopa‐induced complications in Parkinson's disease
Authors: Michałowska Małgorzata , Chalimoniuk Małgorzata , Jówko Ewa , Przybylska Iwona , Langfort Józef , Toczylowska Beata , Krygowska‐Wajs Anna , Fiszer Urszula 
Published: February 2020

AbstractObjectiveThe aim of the study was to evaluate the association of individual and combined single‐nucleotide polymorphisms in brain‐derived neurotrophic factor (BDNF), dopamine transporter (DAT), and catechol‐O‐methyltransferase (COMT) genes with the occurrence of motor levodopa‐induced complications (MLIC) in Parkinson's disease (PD).Materials and MethodsWe studied 76 patients with PD (MLIC occurred in 56.6%) and 60 controls. Allelic discrimination of rs6265 BDNF (Val66Met), rs397595 DAT (SLC6A3), and rs4680 COMT (Val158Met) genes were genotyped. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated using multinominal logistic regression. Orthogonal partial least squares (OPLS) analysis and OPLS discriminant analysis (OPLS‐DA) were used to analyze qualitative genetic data.ResultsThe risk of PD in subjects with the AG BDNF genotype was increased sixfold (OR = 6.12, 95% CI = 2.88–13.02, p < .0001), and AG BDNF and AG DAT genotypes were correlated with PD in OPLS‐DA (VIP > 1). There were no differences in distributions of BDNF, DAT and COMT genotypes between PD groups with and without MLIC, while OPLS model showed that genotype combination of AG BDNF, AG DAT, and GG COMT was correlated with MLIC and genotypes combination of GG BDNF, AA DAT, and AA COMT with lack of MLIC in PD patients (VIP > 1).ConclusionsOur results confirmed the association of rs6265 BDNF (Val66Met) with the risk of PD and suggest a synergic effect of rs6265 BDNF (Val66Met), rs397595 DAT (SLC6A3), and rs4680 COMT (Val158Met) polymorphisms on the occurrence of MLIC.
Early stage neuroglobin level as a predictor of delayed cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage
Authors: Ding Chenyu , Kang Dezhi , Chen Pengqiang , Wang Ziliang , Lin Yuanxiang , Wang Dengliang , Lin Zhangya , Gu Jianjun 
Published: February 2020

AbstractBackgroundThe neuroglobin (Ngb) is well recognized as a potential biomarker for the hypoxic‐ischemic brain injury. However, connection between Ngb and delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) is still unclear.ObjectiveTo investigate the relationship between early stage Ngb level of aSAH patient and the occurrence of DCI.MethodsWe evaluated 126 aSAH patients who were enrolled into a prospective observational cohort study. Serum Ngb level on days 1, 2, 3, 5, and 7 after aSAH were determined using a commercial enzyme‐linked immunosorbent assay kit. The relationship between Ngb level and DCI was analyzed.ResultsForty‐six (36.5%) aSAH patients experienced DCI. Patients with DCI had significantly higher Ngb levels than those without (p < .001). Multivariate model analysis revealed that day 3 Ngb level remained a significant factor after adjusting for World Federation of Neurosurgical Societies (WFNS) grade, modified Fisher grade, clipping and Ngb levels on days 1, 2, 5, and 7. Sensitivity, specificity, and Youden index of day 3 Ngb level for identifying DCI were derived as 73.9%, 72.5%, and 0.46, respectively, based on the best threshold of 8.4 ng/ml. Regardless in good‐grade group or in poor‐grade group, patients having day 3 Ngb level > 8.4 ng/ml has a significantly worse DCI survival rate than those having day 3 Ngb level <=8.4 ng/ml (p = .026 and .009, respectively).ConclusionsSerum Ngb level was significantly elevated in DCI patients. Early stage aSAH Ngb level has the potential of being used as a novel DCI occurrence predictor, especially when Ngb level was combined with WFNS grade.
Identification of nonclinical interventions for spontaneous recovery of depression using mathematical modeling
Authors: Mohan Gayathree , Kandaswamy Dinesh Kumar , Chikkaharohalli Ramakrishna Mohan Kumar 
Published: February 2020

AbstractBackgroundIn order to make a risk or vulnerability assessment of major depressive disorder (MDD) in adolescents and suggest nonclinical interventions for spontaneous recovery for low‐vulnerable adolescents a novel network mathematical model has been proposed.MethodsIn the existing network theory, the theoretical model consists of a symptom network surrounded by the triggering factors as external field which are the cause for adolescents being diagnosed with MDD. But in our network model, the triggering external field is replaced by nonclinical interventions, easily implementable in schools and colleges with teachers as facilitators.ResultsThe four variables of subjective well‐being (SWB), emotional quotient—Attention (EQ‐A), emotional quotient—Clarity (EQ‐C) and emotional quotient—Reparation (EQ‐R) were the symptoms considered for stratification of the vulnerability. The mathematical model was created using the four symptoms and the four nonclinical interventions of technology use, physical exercise, peer pressure positive and peer pressure negative, and their inter‐relationship.ConclusionA balance of tech use and physical exercise and of the peer pressure help maintain the adolescents in the low‐vulnerability group in our study with 227 adolescents in Bangalore. Furthermore, we predict that positive peer pressure and physical exercise could increase the EQ thus suggesting a preventive model for the onset of major depressive disorder (MDD).
Market orientation practices enhancing corporate environmental performance via knowledge creation: Does environmental management system implementation matter?
Authors: Jiang Wenbo , Rosati Francesco , Chai Huaqi , Feng Taiwen 
Published: February 2020

AbstractThe academic literature on environmental management has provided extensive insights into the determinants of corporate environmental performance. However, few empirical studies have explored whether and how three core components of corporate market orientation (i.e., customer orientation, competitor orientation, and interfunctional coordination) affect environmental performance. Building on institutional theory and the absorptive capacity perspective, this study investigates the relationships among market orientation, knowledge creation, and environmental performance, as well as the moderating effects of environmental management system implementation. On the basis of survey data from 237 Chinese manufacturing firms, we used hierarchical multiple regression analyses to test the hypotheses. The findings indicate that knowledge creation completely mediates the influence of competitor orientation on environmental performance and partially mediates the influence of customer orientation and interfunctional coordination on environmental performance. In addition, environmental management system implementation positively moderates the relationship between knowledge exchange and environmental performance.
The clinical significance of the retromolar canal and foramen in dentistry
Authors: Ngeow Wei Cheong , Chai Wen Lin 
Published: February 2020

AbstractThe mandibular canal is nowadays acknowledged as a major trunk with multiple smaller branches running roughly parallel to it. Most of these accessory canals contain branches of the inferior alveolar neurovascular bundle that supplies the dentition, jawbone, and soft tissue around the gingiva and lower lip. This article reviews the prevalence, classification and morphometric measurements of the retromolar canal and its aperture. A retromolar canal is a bifid variation of the mandibular canal that divides from above this main canal, and travels anterosuperiorly within the bone to exit via a single foramen or multiple foramina into the retromolar fossa. This foramen, termed the retromolar foramen, allows accessory branches of the inferior alveolar neurovascular bundles to supply tissues at the retromolar trigone. Clinically, it is of the utmost importance to determine the exact location of the mandibular canal and to identify its retromolar accessory branches when surgery in the posterior mandible is to be performed.