bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formation of Polymeric Nanocubes by Self‐Assembly and Crystallization of Dithiolane‐Containing Triblock Copolymers
Authors: Margulis Katherine , Zhang Xiangyi , Joubert Lydia‐Marie , Bruening Karsten , Tassone Christopher J. , Zare Richard N. , Waymouth Robert M. 
Published: October 2017

AbstractTemplate‐free fabrication of non‐spherical polymeric nanoparticles is desirable for various applications, but has had limited success owing to thermodynamic favorability of sphere formation. Herein we present a simple way to prepare cubic nanoparticles of block copolymers by self‐assembly from aqueous solutions at room temperature. Nanocubes with edges of 40–200 nm are formed spontaneously on different surfaces upon water evaporation from micellar solutions of triblock copolymers containing a central poly(ethylene oxide) block and terminal trimethylene carbonate/dithiolane blocks. These polymers self‐assemble into 28±5 nm micelles in water. Upon drying, micelle aggregation and a kinetically controlled crystallization of central blocks evidently induce solid cubic particle formation. An approach for preserving the structures of these cubes in water by thiol‐ or photo‐induced crosslinking was developed. The ability to solubilize a model hydrophobic drug, curcumin, was also explored.
Gold‐Catalyzed Asymmetric Intramolecular Cyclization of N‐Allenamides for the Synthesis of Chiral Tetrahydrocarbolines
Authors: Wang Yidong , Zhang Peichao , Di Xiaoyu , Dai Qiang , Zhang Zhan‐Ming , Zhang Junliang 
Published: October 2017

AbstractHighly enantioselective gold‐catalyzed intramolecular cyclization of N‐allenamides was implemented by utilizing a designed chiral sulfinamide phosphine ligand (PC‐Phos). This represents the first example of highly enantioselective intramolecular cyclization of N‐allenamides. The practicality of this reaction was validated in the total synthesis of (R)‐desbromoarborescidine A and formal synthesis of (R)‐desbromoarborescidine C and (R)‐deplancheine. Moreover, the catalyst system PC‐Phos/AuNTf2 proved to be specifically efficient to promote the desymmetrization of N‐allenamides in excellent yields with satisfactory ee values.
Genomes in Focus: Development and Applications of CRISPR‐Cas9 Imaging Technologies
Authors: Knight Spencer C. , Tjian Robert , Doudna Jennifer A. 
Published: October 2017

AbstractThe discovery of the CRISPR‐Cas9 endonuclease has enabled facile genome editing in living cells and organisms. Catalytically inactive Cas9 (dCas9) retains the ability to bind DNA in an RNA‐guided fashion, and has additionally been explored as a tool for transcriptional modulation, epigenetic editing, and genome imaging. This Review highlights recent progress and challenges in the development of dCas9 for imaging genomic loci. The emergence and maturation of this technology offers the potential to answer mechanistic questions about chromosome dynamics and three‐dimensional genome organization in vivo.
Auditory brainstem response in infants and children with autism spectrum disorder: A meta‐analysis of wave V
Authors: Miron Oren , Beam Andrew L. , Kohane Isaac S. 
Published: October 2017

Infants with autism spectrum disorder (ASD) were recently found to have prolonged auditory brainstem response (ABR); however, at older ages, findings are contradictory. We compared ABR differences between participants with ASD and controls with respect to age using a meta‐analysis. Data sources included MEDLINE, EMBASE, Web of Science, Google Scholar, HOLLIS, and ScienceDirect from their inception to June 2016. The 25 studies that were included had a total of 1349 participants (727 participants with ASD and 622 controls) and an age range of 0–40 years. Prolongation of the absolute latency of wave V in ASD had a significant negative correlation with age (R2 = 0.23; P = 0.01). The 22 studies below age 18 years showed a significantly prolonged wave V in ASD (Standard Mean Difference = 0.6 [95% CI, 0.5–0.8]; P < 0.001). The 3 studies above 18 years of age showed a significantly shorter wave V in ASD (SMD = −0.6 [95% CI, −1.0 to −0.2]; P = 0.004). Prolonged ABR was consistent in infants and children with ASD, suggesting it can serve as an ASD biomarker at infancy. As the ABR is routinely used to screen infants for hearing impairment, the opportunity for replication studies is extensive. Autism Res 2018, 11: 355–363. © 2017 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc.Lay SummaryOur analysis of previous studies showed that infants and children with autism spectrum disorder (ASD) have a slower brain response to sound, while adults have a faster brain response to sound. This suggests that slower brain response in infants may predict ASD risk. Brain response to sound is routinely tested on newborns to screen hearing impairment, which has created large data sets to afford replication of these results.
Pupillary Response and Phenotype in ASD: Latency to Constriction Discriminates ASD from Typically Developing Adolescents
Authors: Lynch Georgina T.F. , James Stephen M. , VanDam Mark 
Published: October 2017

Brain imaging data describe differences in the ASD brain, including amygdala overgrowth, neural interconnectivity, and a three‐phase model of neuroanatomical changes from early post‐natal development through late adolescence. The pupil reflex test (PRT), a noninvasive measure of brain function, may help improve early diagnosis and elucidate underlying physiology in expression of ASD endophenotype. Commonly observed characteristics of ASD include normal visual acuity but difficulty with eye gaze and photosensitivity, suggesting deficient neuromodulation of cranial nerves. Aims of this study were to confirm sensitivity of the PRT for identifying adolescents with ASD, determine if a phenotype for a subtype of ASD marked by pupil response is present in adolescence, and determine whether differences could be observed on a neurologic exam testing cranial nerves II and III (CNII; CNIII). Using pupillometry, constriction latency was measured serving as a proxy for recording neuromodulation of cranial nerves underlying the pupillary reflex. The swinging flashlight method, used to perform the PRT for measuring constriction latency and return to baseline, discriminated ASD participants from typically developing adolescents on 72.2% of trials. Results further confirmed this measure's sensitivity within a subtype of ASD in later stages of development, serving as a correlate of neural activity within the locus–coeruleus norepinephrine (LC–NE) system. A brainstem model of atypical PRT in ASD is examined in relation to modulation of cranial nerves and atypical arousal levels subserving the atypical pupillary reflex. Autism Res 2018, 11: 364–375. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.Lay SummaryMilder forms of autism spectrum disorder (ASD) can be difficult to diagnose based on behavioral testing alone. This study used eye‐tracking equipment and a hand‐held penlight to measure the pupil reflex in adolescents with “high functioning” ASD and in adolescents without ASD. The ASD group showed a delay in pupil response. This is the first eye‐tracking study to conduct this test as typically performed by a clinical provider, demonstrating differences in older individuals with a subtype of ASD.
Structure‐based analysis of Clot as a thioredoxin‐related protein of 14 kDa in Drosophila via experimental and computational approaches
Authors: Kim Kiyoung 
Published: October 2017

AbstractThe clot gene is required for the biosynthesis of drosopterins, the red components of Drosophila eye pigments. However, the enzymatic role of Clot in Drosophila eye pigment formation and the molecular mechanisms underlying Clot function are not fully elucidated. In this study, we cloned and characterized Clot derived from Drosophila cDNA, and results showed that Clot exhibited ∼30% sequence identity with mammalian TRP14. In addition, we reported the three‐dimensional structure of Drosophila Clot based on homology modeling. Furthermore, we identified NFκB as a novel Clot substrate using the I‐TASSER program. The NFκB fragment can bind near the active site of Clot. These findings predicted the novel regulatory mechanisms underlying Clot function in the pyrimidodiazepine synthesis pathway and increased the understanding of the molecular mechanisms and physiological function of Clot in Drosophila eye pigment formation.
Dynamic modeling of green algae cultivation in a photobioreactor for sustainable biodiesel production
Authors: del Rio‐Chanona Ehecatl A. , Liu Jiao , Wagner Jonathan L. , Zhang Dongda , Meng Yingying , Xue Song , Shah Nilay 
Published: October 2017

AbstractBiodiesel produced from microalgae has been extensively studied due to its potentially outstanding advantages over traditional transportation fuels. In order to facilitate its industrialization and improve the process profitability, it is vital to construct highly accurate models capable of predicting the complex behavior of the investigated biosystem for process optimization and control, which forms the current research goal. Three original contributions are described in this paper. Firstly, a dynamic model is constructed to simulate the complicated effect of light intensity, nutrient supply and light attenuation on both biomass growth and biolipid production. Secondly, chlorophyll fluorescence, an instantly measurable variable and indicator of photosynthetic activity, is embedded into the model to monitor and update model accuracy especially for the purpose of future process optimal control, and its correlation between intracellular nitrogen content is quantified, which to the best of our knowledge has never been addressed so far. Thirdly, a thorough experimental verification is conducted under different scenarios including both continuous illumination and light/dark cycle conditions to testify the model predictive capability particularly for long‐term operation, and it is concluded that the current model is characterized by a high level of predictive capability. Based on the model, the optimal light intensity for algal biomass growth and lipid synthesis is estimated. This work, therefore, paves the way to forward future process design and real‐time optimization.
Metabolic phenotyping of CHO cells varying in cellular biomass accumulation and maintenance during fed‐batch culture
Authors: Fernandez‐Martell Alejandro , Johari Yusuf B. , James David C. 
Published: October 2017

AbstractCHO cell lines capable of high‐level recombinant protein product biosynthesis during fed‐batch culture are still generally obtained by intensive empirical screening of transfected cells rather than knowledge‐guided cellular engineering. In this study, we investigate how CHO cell lines create and maintain cellular biosynthetic capacity during fed‐batch culture to achieve the optimal combination of rapid exponential proliferation and extended maintenance of high cell biomass concentration. We perform a comparative meta‐analysis of mitochondrial and glycolytic functions of 22 discrete parental CHO cell lineages varying in fed‐batch culture performance to test the hypotheses that (i) “biomass‐intensive” CHO cells exhibit conserved differences in metabolic programming and (ii) it is possible to isolate parental CHO cell lines with a biomass‐intensive phenotype to support fed‐batch bioproduction processes. We show that for most parental CHO cell lines, rapid proliferation and high late‐stage culture performance are mutually exclusive objectives. However, quantitative dissection of mitochondrial and glycolytic functions revealed that a small proportion of clones utilize a conserved metabolic program that significantly enhances cellular glycolytic and mitochondrial oxidative capacity at the onset of late‐stage culture. We reveal the central importance of dynamic metabolic re‐programming to activate oxidative mitochondrial function as a necessary mechanism to support CHO cell biosynthetic performance during culture.
MiR‐29b expression is associated with a dexmedetomidine‐mediated protective effect against oxygen‐glucose deprivation‐induced injury to SK‐N‐SH cells in vitro
Authors: Huang Zhi , Liu Guoli , Zeng Qingfan , Gao Rui , Zhang Shuai , Wang Lizhou , Liu Bingjie , Yu YanLong , Zhao Ansu , Li Rui , Zhou Shi , Yu Wenfeng 
Published: October 2017

AbstractIschemic cerebral stroke is a leading cause of death and long‐term disability world‐wide. Neuronal injury following cerebral ischemia initiates a complex series of signaling cascades that lead to neuronal cell death. MicroRNA 29b (miR‐29b) has reported involvement in the pathogenic process of ischemic brain injury. Dexmedetomidine (Dex) is a highly selective α2 adrenergic receptor stimulant that exerts a protective effect on brain tissue. To determine whether Dex might directly influence miR‐29b expression after an ischemic injury, human neuroblastoma SK‐N‐SH cells were subjected to oxygen‐glucose deprivation (OGD) for the purpose of creating a neuronal injury model that mimics the effects of brain ischemia in vitro. Next, the association of miR‐29b with the protective effect of Dex against ischemic brain injury was studied through the enhancement or inhibition of miR‐29b expression by transfection with an miR‐29b mimic or inhibitor. We demonstrated that Dex treatment could reduce miR‐29b expression, increase cell viability, and inhibit cell apoptosis in the OGD‐induced neuronal injury model in vitro. Furthermore, down‐regulation of miR‐29b expression produced effects on OGD‐induced neuronal injuries that were similar to those produced by Dex treatment. Moreover, up‐regulation of miR‐29b reversed the protective effect of Dex treatment against OGD‐induced neuronal injury. Therefore, down‐regulation of miR‐29b expression might play a role in anti‐apoptotic signaling similar to that played by Dex. Elucidation of the role played by miR‐29b in ischemia, and identification of a definite association between Dex and miR‐29b may lead to the development of new strategies for treating ischemic brain injuries.
An Interface‐Controlled Redox Switch for Wastewater Remediation
Authors: Khaire Siddhi , Gaikwad Pramod , Aralekallu Shambhulinga , Bhat Zahid Manzoor , Kottaichamy Alagar Raja , Devendrachari Mruthyunjayachari Chattanahalli , Thimmappa Ravikumar , Shafi Shahid Pottachola , Gautam Manu , Thotiyl Musthafa Ottakam 
Published: October 2017

AbstractBipolar junction transistors (BJTs) can function as electrically reversible switches; nevertheless, triggering such circuits requires a distinct voltage bias at the base terminal. Here, we show a proof‐of‐concept of an electrochemical switching device equipped with a redox electrode whose bi‐stable interfacial chemistry, reliant on hydronium ion strength, can provide distinct logic HIGH (1) and logic LOW (0) levels of operation, enabling it to control and command an electronic circuit without the aid of any external voltage input. Electrochemical impedance spectroscopy, quartz crystal microbalance studies, and UV/Vis spectroscopy demonstrate that discrete logic levels are controlled by the solvent‐mediated charge injection/ejection kinetics at the redox‐active half‐cell electrode, leading to a chemically reversible switch with a response time of approximately 1 s and an operating speed of 225 cycles per hour. We demonstrate that the logic HIGH level of the interfacial twin states is actuated when exposed to acid‐contaminated wastewater, automatically triggering the command for remediation.
Synthesis of new C3 symmetric amino acid‐ and aminoalcohol‐containing chiral stationary phases and application to HPLC enantioseparations
Authors: Yu Jeongjae , Armstrong Daniel W. , Ryoo Jae Jeong 
Published: October 2017

AbstractWe recently reported a new C3‐symmetric (R)‐phenylglycinol N‐1,3,5‐benzenetricarboxylic acid‐derived chiral high‐performance liquid chromatography (HPLC) stationary phase (CSP 1) that demonstrated better results as compared to a previously described N‐3,5‐dintrobenzoyl (DNB) (R)‐phenylglycinol‐derived CSP. Over a decade ago, (S)‐leucinol, (R)‐phenylglycine, and (S)‐leucine derivatives were used as the starting materials of 3,5‐DNB‐based Pirkle‐type CSPs for chiral separation. In this study, three new C3‐symmetric CSPs (CSP 2, 3, and 4) were prepared by combining the ideas and results mentioned above. Here we describe the synthetic procedures and applications of the new C3‐symmetric CSPs (CSP 2–CSP 4).
Evaluation of effect of temperature and pressure on the dynamic interfacial tension of crude oil/aqueous solutions containing chloride anion through experimental and modelling approaches
Authors: Lashkarbolooki Mostafa , Ayatollahi Shahab 
Published: October 2017

AbstractThe interfacial properties of crude oil are highly complex and are not yet well understood. This study aimed to evaluate the effect of temperature (30–80 °C) and pressure (3.44–27.58 MPa) on the dynamic interfacial tension (IFT) of crude oil/aqueous solutions consisting of 15 000 ppm of salt containing different chloride anions, e.g. NaCl, KCl, MgCl2, and CaCl2. To reach this goal, several parameters, such as dynamic and equilibrium IFT, adsorption time, diffusivity of resin, and asphaltene as surface‐active agents from bulk of crude oil towards fluid/fluid interface and surface excess concentration of them at the interface, were compared as a function of temperature, pressure, and ion type. The obtained results clarified the reason why there are contradicting observations in the literature on the influence of temperature on the equilibrium IFT of crude oil/brine solutions.
A two‐level directional model for dependence in circular data
Authors: Holmquist Björn , Gustafsson Peter 
Published: October 2017

AbstractWe present a likelihood‐based test for clustering among sub‐population mean directions for circular data. The test is based on a two‐level hierarchical model with von Mises distributed variation on each level. The properties of the tests are investigated and compared to the commonly applied techniques of second‐order analysis and pseudo‐pooling of directions for the situation at hand. Finally we apply the technique to some previously published data sets, to determine the presence of directional clustering among the sub‐populations. The Canadian Journal of Statistics 45: 461–478; 2017 © 2017 Statistical Society of Canada
Thermodynamic measurements of actin polymerization with various cation species
Authors: Kikumoto Mahito , Oosawa Fumio 
Published: October 2017

AbstractWe measured the critical concentration of actin polymerized with different polymerization ions and bound divalent cations at low temperatures and estimated thermodynamic parameters. The entropy and enthalpy changes of actin polymerization were 36–55 (cal/mol K) and 2–8 (kcal/mol), respectively, with some exceptions. Both the entropy and enthalpy changes of the polymerization of Ca2+‐actin were sensitive to the polymerization ion (K+ or Na+): ΔS = 39 or 36 (cal/mol K), ΔΗ= 3.9 or 2.7 (kcal/mol). The entropy and enthalpy changes (cal/mol K, kcal/mol) of Mg2+‐actin were also sensitive to the polymerization ion in the following order: Mg2+ (55, 7.6) > K+ (46, 5.3) > Na+ (38, 2.4). Those values largely decreased and became even negative in the presence of a high concentration (0.1 M) of K+, which was likely caused by the charge screening effect of that ion.
Design, Synthesis, Molecular Modeling, and Biological Evaluation of Novel Amine‐based Histone Deacetylase Inhibitors
Authors: Abdelkarim Hazem , Neelarapu Raghupathi , Madriaga Antonett , Vaidya Aditya S. , Kastrati Irida , Karumudi Bhargava , Wang Yue‐ting , Taha Taha Y. , Thatcher Gregory R. J. , Frasor Jonna , Petukhov Pavel A. 
Published: October 2017

AbstractHistone deacetylases (HDACs) are promising drug targets for a variety of therapeutic applications. Herein we describe the design, synthesis, biological evaluation in cellular models of cancer, and preliminary drug metabolism and pharmacokinetic studies (DMPK) of a series of secondary and tertiary N‐substituted 7‐aminoheptanohydroxamic acid‐based HDAC inhibitors. Introduction of an amino group with one or two surface binding groups (SBGs) yielded a successful strategy to develop novel and potent HDAC inhibitors. The secondary amines were found to be generally more potent than the corresponding tertiary amines. Docking studies suggested that the SBGs of tertiary amines cannot be favorably accommodated at the gorge region of the binding site. The secondary amines with naphthalen‐2‐ylmethyl, 5‐phenylthiophen‐2‐ylmethyl, and 1H‐indol‐2‐ylmethyl (2 j) substituents exhibited the highest potency against class I HDACs: HDAC1 IC50 39–61 nm, HDAC2 IC50 260–690 nm, HDAC3 IC50 25–68 nm, and HDAC8 IC50 320–620 nm. The cytotoxicity of a representative set of secondary and tertiary N‐substituted 7‐aminoheptanoic acid hydroxyamide‐based inhibitors against HT‐29, SH‐SY5Y, and MCF‐7 cancer cells correlated with their inhibition of HDAC1, 2, and 3 and was found to be similar to or better than that of suberoylanilide hydroxamic acid (SAHA). Compounds in this series increased the acetylation of histones H3 and H4 in a time‐dependent manner. DMPK studies indicated that secondary amine 2 j is metabolically stable and has plasma and brain concentrations >23‐ and >1.6‐fold higher than the IC50 value for class I HDACs, respectively. Overall, the secondary and tertiary N‐substituted 7‐aminoheptanoic acid hydroxyamide‐based inhibitors exhibit excellent lead‐ and drug‐like properties and therapeutic capacity for cancer applications.
Theranostic Hyaluronic Acid–Iron Micellar Nanoparticles for Magnetic‐Field‐Enhanced in vivo Cancer Chemotherapy
Authors: Wang Guohao , Gao Shi , Tian Rui , Miller‐Kleinhenz Jasmine , Qin Zainen , Liu Tianji , Li Lu , Zhang Fan , Ma Qingjie , Zhu Lei 
Published: October 2017

AbstractThe delivery of therapeutic cancer agents using nanomaterials has recently attracted much attention. Although encouraging progress with chemotherapeutics has been made, tumor treatment response remains unsatisfactory. To address this concern, we constructed a new micellar nanocomplex by covalently conjugating hyaluronic acid (HA) with an iron oxide nanoparticle (IONP). When an external magnetic field was applied to the tumor area, HA–IONP specifically accumulated in the tumor, due to the strong IONP magnetism. In addition, HA was shown to bind to cluster determinant 44 (CD44), which is overexpressed on tumor cells. With combined magnetic, CD44, and enhanced permeability retention (EPR) targeting, the efficient delivery of HA–IONP to the tumor is expected to enhance cancer treatment efficiency. After encapsulation of the chemotherapy drug homocamptothecin (HCPT), the theranostic potency of HA–IONP/HCPT (HIH) was investigated both in vitro and in vivo. The improved tumor homing behavior of HIH was observed by magnetic resonance imaging (MRI) when an external magnetic field was used. Moreover, HIH showed remarkable tumor ablation efficiency, with magnetic targeting after 3 mg kg−1 intravenous administration (equivalent dose of free HCPT), and the tumors almost disappeared after treatment. No obvious systemic toxicity was detected. This excellent biocompatibility and tumor targetability suggests that HIH is a promising theranostic nanocomplex with great translational potency. Application of the HA–IONP platform could also be extended to delivery of other hydrophobic chemotherapy drugs or phototherapy agents.