bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyoxometalate/Polyethylene Glycol Interactions in Water: From Nanoassemblies in Water to Crystal Formation by Electrostatic Screening
Authors: Buchecker Thomas , Le Goff Xavier , Naskar Bappaditya , Pfitzner Arno , Diat Olivier , Bauduin Pierre 
Published: March 2017

AbstractIn the last decade organic–inorganic hybrid materials have become essential in materials science as they combine properties of both building blocks. Nowadays the main routes for their synthesis involve electrostatic coupling, covalent grafting, and/or solvent effects. In this field, polyoxometalates (POMs) have emerged as interesting inorganic functional building blocks due to their outstanding properties. In the present work the well‐known α‐Keggin polyoxometalate, α‐PW12O403− (PW), is shown to form hybrid crystalline materials with industrial (neutral) polyethylene glycol oligomers (PEG) under mild conditions, that is, in aqueous medium and at room temperature. The formation of these materials originates from the spontaneous self‐assembly of PW with EOx, (EO=ethylene oxide) with at least four EO units (x>4). The PW–PEG nanoassemblies, made of a POM surrounded by about two PEG oligomers, are stabilized by electrostatic repulsions between the negatively charged PW anions. Addition of NaCl, aimed at screening the inter‐nanoassembly repulsions, induces aggregation and formation of hybrid crystalline materials. Single‐crystal analysis showed a high selectivity of PW towards EO5–EO6 oligomers from PEG200, which is made of a mixture of EO3–8. Therefore, a general “soft” route to produce POM–organic composites is proposed here through the control of electrostatic repulsions between spontaneously formed nanoassemblies in water. However, this rational design of new POM hybrid (crystalline) materials with hydrophilic blocks, using such a simple mixing procedure of the components, requires a deep understanding of the molecular interactions.
Detecting Membrane Protein‐protein Interactions Using the Mammalian Membrane Two‐hybrid (MaMTH) Assay
Authors: Saraon Punit , Grozavu Ingrid , Lim Sang Hyun , Snider Jamie , Yao Zhong , Stagljar Igor 
Published: March 2017

AbstractProtein‐protein interactions (PPIs) play an integral role in numerous cellular processes. Membrane protein interactions, in particular, are critical in cellular responses to stresses and stimuli, with dysfunction of these PPIs (e.g., due to aberrant expression and/or mutation of interaction partners) leading to a diverse array of pathological states. Exploration of the interaction space and dynamics of membrane proteins is difficult due to the limitations of current techniques used to study proteins in the biochemically complex environment of biological membranes. In the protocols below, we describe a newly developed membrane protein interaction assay called the Mammalian‐Membrane Two‐Hybrid (MaMTH), designed specifically for the detection of integral membrane PPIs in the context of living mammalian cells. Prior to using MaMTH, cell lines of interest are genetically modified to encode a reporter of choice. MaMTH “bait” and “prey” constructs of interest are also generated using Gateway cloning technology. The assay is then performed by co‐transfection of baits and preys, with bait‐prey interaction quantifiably assessed by way of a reporter signal (e.g., light (luciferase), fluorescence (GFP). © 2017 by John Wiley & Sons, Inc.
Deformability Calculation for Estimation of the Relative Stability of Chemically Modified RNA Duplexes
Authors: Masaki Yoshiaki , Sekine Mitsuo , Seio Kohji 
Published: March 2017

AbstractChemical modification of RNA duplexes alters their stability. We have attempted to develop a computational approach to estimate the thermal stability of chemically modified duplexes. These studies revealed that the deformability of chemically modified RNA duplexes, calculated from molecular dynamics simulations, could be used as a good indicator for estimating the effect of chemical modification on duplex thermal stability. This unit describes how deformability calculation can be applied to estimate the relative stability of chemically modified RNA duplexes. © 2017 by John Wiley & Sons, Inc.
2‐Pyridinyl Thermolabile Groups as General Protectants for Hydroxyl, Phosphate, and Carboxyl Functions
Authors: Brzezinska Jolanta , Witkowska Agnieszka , Kaczyński Tomasz P. , Krygier Dominika , Ratajczak Tomasz , Chmielewski Marcin K. 
Published: March 2017

AbstractApplication of 2‐pyridinyl thermolabile protecting groups (2‐PyTPGs) for protection of hydroxyl, phosphate, and carboxyl functions is presented in this unit. Their characteristic feature is a unique removal process following the intramolecular cyclization mechanism and induced only by temperature rise. Deprotection rate of 2‐PyTPGs is dependent on certain parameters, such as solvent (aqueous or non‐aqueous medium), pH values, and electron distribution in a pyridine ring. The presented approach pertains not only to protecting groups but also to an advanced system of controlling certain properties of 2‐pyridinyl derivatives. We improved the “chemical switch” method, allowing us to regulate the protecting group stability by inversing the electron distribution in 2‐PyTPG. Together with pH values manipulation, this allows us to regulate the protecting group stability. Moreover, phosphite cyclization to oxazaphospholidine provides a very stable but easily reversible tool for phosphate protection/modifications. For all TPGs we confirmed their utility in a system of protecting groups. This concept can contribute to designing the general protecting group that could be useful in bioorganic chemistry. © 2017 by John Wiley & Sons, Inc.
Ecological application of biotic resistance to control the invasion of an invasive plant, Ageratina altissima
Authors: Byun Chaeho , Lee Eun Ju 
Published: March 2017

AbstractBiotic resistance is the ability of species in a community to limit the invasion of other species. However, biotic resistance is not widely used to control invasive plants. Experimental, functional, and modeling approaches were combined to investigate the processes of invasion by Ageratina altissima (white snakeroot), a model invasive species in South Korea. We hypothesized that (1) functional group identity would be a good predictor of biotic resistance to A. altissima, whereas a species identity effect would be redundant within a functional group, and (2) mixtures of species would be more resistant to invasion than monocultures. We classified 37 species of native plants into three functional groups based on seven functional traits. The classification of functional groups was based primarily on differences in life longevity and woodiness. A competition experiment was conducted based on an additive competition design with A. altissima and monocultures or mixtures of resident plants. As an indicator of biotic resistance, we calculated a relative competition index (RCIavg) based on the average performance of A. altissima in a competition treatment compared with that of the control where only seeds of A. altissima were sown. To further explain the effect of diversity, we tested several diversity–interaction models. In monoculture treatments, RCIavg of resident plants was significantly different among functional groups but not within each functional group. Fast‐growing annuals (FG1) had the highest RCIavg, suggesting priority effects (niche pre‐emption). RCIavg of resident plants was significantly greater in a mixture than in a monoculture. According to the diversity–interaction models, species interaction patterns in mixtures were best described by interactions between functional groups, which implied niche partitioning. Functional group identity and diversity of resident plant communities were good indicators of biotic resistance to invasion by introduced A. altissima, with the underlying mechanisms likely niche pre‐emption and niche partitioning. This method has most potential in assisted restoration contexts, where there is a desire to reintroduce natives or boost their population size due to some previous level of degradation.
A nutritional supplement containing lactoferrin stimulates the immune system, extends lifespan, and reduces amyloid β peptide toxicity in Caenorhabditis elegans
Authors: Martorell Patricia , Llopis Silvia , Gonzalez Nuria , Ramón Daniel , Serrano Gabriel , Torrens Ana , Serrano Juan M. , Navarro Maria , Genovés Salvador 
Published: March 2017

AbstractLactoferrin is a highly multifunctional glycoprotein involved in many physiological functions, including regulation of iron absorption and immune responses. Moreover, there is increasing evidence for neuroprotective effects of lactoferrin. We used Caenorhabditis elegans as a model to test the protective effects, both on phenotype and transcriptome, of a nutraceutical product based on lactoferrin liposomes. In a dose‐dependent manner, the lactoferrin‐based product protected against acute oxidative stress and extended lifespan of C. elegans N2. Furthermore, Paralysis of the transgenic C. elegans strain CL4176, caused by Aβ1‐42 aggregates, was clearly ameliorated by treatment. Transcriptome analysis in treated nematodes indicated immune system stimulation, together with enhancement of processes involved in the oxidative stress response. The lactoferrin‐based product also improved the protein homeostasis processes, cellular adhesion processes, and neurogenesis in the nematode. In summary, the tested product exerts protection against aging and neurodegeneration, modulating processes involved in oxidative stress response, protein homeostasis, synaptic function, and xenobiotic metabolism. This lactoferrin‐based product is also able to stimulate the immune system, as well as improving reproductive status and energy metabolism. These findings suggest that oral supplementation with this lactoferrin‐based product could improve the immune system and antioxidant capacity. Further studies to understand the molecular mechanisms related with neuronal function would be of interest.
Node‐positive cutaneous squamous cell carcinoma of the head and neck: Survival, high‐risk features, and adjuvant chemoradiotherapy outcomes
Authors: Amoils Misha , Lee Carolyn S. , Sunwoo John , Aasi Sumaira Z. , Hara Wendy , Kim Jinah , Sirjani Davud , Colevas A. Dimitrios , Chang Anne Lynn S. , Divi Vasu 
Published: March 2017

ABSTRACTBackgroundData lacks to guide treatment of regionally metastatic cutaneous head and neck squamous cell carcinoma (HNSCC).MethodsWe conducted a retrospective review of 80 patients treated for regionally metastatic cutaneous HNSCC. The effect of various clinicopathologic variables on overall survival (OS) was investigated, in addition to outcomes by treatment modality.ResultsOn multivariate regression, cutaneous primary >2 cm (p = .03) and extracapsular spread (ECS; p = .01) were significantly associated with decreased OS. Location of regional metastasis (neck vs parotid vs both) had no effect on OS (p = .2), nor did the presence of a cutaneous primary at the time of presentation (p = .9). The 3‐year survival was 43%, 52%, and 49% for surgery alone, adjuvant radiation, and adjuvant chemoradiation, respectively. Fifty‐one percent of patients had a recurrence of their disease.ConclusionRegionally metastatic cutaneous HNSCC is an aggressive disease associated with high recurrence rates. Patients with tumors >2 cm and ECS have poorer OS despite adjuvant therapy. © 2017 Wiley Periodicals, Inc. Head Neck 39: 881–885, 2017
Defining the surgical margins of adenoid cystic carcinoma and their impact on outcome: An international collaborative study
Authors: Amit Moran , Na'ara Shorook , Trejo–Leider Leonor , Ramer Naomi , Burstein David , Yue Ma , Miles Brett , Yang Xinjie , Lei Delin , Bjoerndal Kristine , Godballe Christian , Mücke Thomas , Wolff Klaus‐Dietrich , Eckardt André M. , Copelli Chiara , Sesenna Enrico , Patel Snehal , Ganly Ian , Gil Ziv 
Published: March 2017

ABSTRACTBackgroundThe mainstay of treatment in adenoid cystic carcinoma (ACC) of the head and neck is surgical resection with negative margins. The purpose of this study was to define the margin status that associates with survival outcomes of ACC of the head and neck.MethodsWe conducted univariate and multivariate analyses of international data.ResultsData of 507 patients with ACC of the head and neck were analyzed; negative margins defined as ≥5 mm were detected in 253 patients (50%). On multivariate analysis, the hazard ratios (HRs) of positive margin status were 2.68 (95% confidence interval [CI], 1.2–6.2; p = .04) and 2.63 (95% CI, 1.1–6.3; p = .03) for overall survival (OS) and disease‐specific survival (DSS), respectively. Close margins had no significant impact on outcome, with HRs of 1.1 (95% CI, 0.4–3.0; p = .12) and 1.07 (95% CI, 0.3–3.4; p = .23) for OS and DSS, respectively, relative with negative margins.ConclusionIn head and neck ACC, positive margins are associated with the worst outcome. Negative or close margins are associated with improved outcome, regardless of the distance from the tumor. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1008–1014, 2017
Herbicide oryzalin inhibits human carbonic anhydrases in vitro
Authors: Baranauskiene Lina , Matulis Daumantas 
Published: March 2017

AbstractHerbicides of the dinitroaniline chemical class, widely used oryzalin and trifluralin, and also nitralin were tested as inhibitors of recombinant human carbonic anhydrases (CAs). Oryzalin bound and inhibited 11 out of 12 catalytically active CA isoforms present in the human body with the affinities in the same range as clinically used CA drugs, while no effect was detected for the other two compounds. Binding of all three herbicides was examined by fluorescence‐based thermal shift assay, isothermal titration calorimetry, and the inhibition of carbon dioxide hydratase activity. During the last decade, dinitroaniline compound‐based therapies against protozoan diseases are being developed. Therefore, it is important to investigate their potential off‐target effects, including human CAs.
Enriched Environment Increases PCNA and PARP1 Levels in Octopus vulgaris Central Nervous System: First Evidence of Adult Neurogenesis in Lophotrochozoa
Authors: Bertapelle Carla , Polese Gianluca , Di Cosmo Anna 
Published: March 2017

ABSTRACTOrganisms showing a complex and centralized nervous system, such as teleosts, amphibians, reptiles, birds and mammals, and among invertebrates, crustaceans and insects, can adjust their behavior according to the environmental challenges. Proliferation, differentiation, migration, and axonal and dendritic development of newborn neurons take place in brain areas where structural plasticity, involved in learning, memory, and sensory stimuli integration, occurs. Octopus vulgaris has a complex and centralized nervous system, located between the eyes, with a hierarchical organization. It is considered the most “intelligent” invertebrate for its advanced cognitive capabilities, as learning and memory, and its sophisticated behaviors. The experimental data obtained by immunohistochemistry and western blot assay using proliferating cell nuclear antigen and poli (ADP‐ribose) polymerase 1 as marker of cell proliferation and synaptogenesis, respectively, reviled cell proliferation in areas of brain involved in learning, memory, and sensory stimuli integration. Furthermore, we showed how enriched environmental conditions affect adult neurogenesis.
A simple method to assess the impact of sealing, headspace mixing and pressure vent on airtightness of manually closed chambers
Authors: Hoffmann Mathias , Pehle Natalia , Huth Vytas , Jurisch Nicole , Sommer Michael , Augustin Jürgen 
Published: March 2017

AbstractWithin a full‐factorial laboratory experiment, three different designs and two modifications of typical manual closed chamber setups were tested for sealing integrity. Tests were performed using a simple method, based on injections of single CO2 pulses. Chamber designs differed in V:A‐ratio and chamber‐collar sealing (water, rubber‐foam, rubber‐tube). All chambers were tested with and without pressure vent and fan. Our results indicate significant differences in sealing integrity due to chamber‐collar sealing strategy. Especially rubber sealing turned out to be characterized by a certain non‐reliability. The effect of vent and fan, however, was of minor importance. The proposed setup is an effective way to assess the airtightness of manual chambers for subsequent field studies.
Impact of pyrochar and hydrochar on soybean (Glycine max L.) root nodulation and biological nitrogen fixation
Authors: Scheifele Michael , Hobi Andrea , Buegger Franz , Gattinger Andreas , Schulin Rainer , Boller Thomas , Mäder Paul 
Published: March 2017

AbstractThe aim of this study was to identify effects of carbonized organic material (“biochar”) on soybean growth, root nodulation and biological nitrogen fixation, and to elucidate possible underlying mechanisms.Soybean (Glycine max L.) was grown in four arable soils amended with carbonized organic material produced from wood or maize as feedstocks, by pyrolysis (“pyrochar”) or hydrothermal carbonization (“hydrochar”). Nodulation by Bradyrhizobium, biological nitrogen fixation (BNF) assessed by 15N techniques, plant growth, nutrient uptake and changes in chemical soil properties after soil amendment were determined. Data were analyzed by means of a three way ANOVA on the factors soil, carbonization technique and feedstock. It turned out that soybean root nodulation and BNF was influenced by the carbonization technique used to prepare the soil amendment. Hydrochar, in average and across all soils, increased nodule dry matter and BNF by factors of 3.4 and 2.3, respectively, considerably more than pyrochar, which led to 1.8 and 1.2 fold increases, respectively. Nodule dry matter and BNF correlated positively with available soil sulfur and negatively with available soil nitrogen. Hydrochars provided more available sulfur than pyrochars, and hydrochars caused a decrease in nitrogen availability in the soil solution, thereby exerting a positive influence on nodulation and BNF. Pyrochar amendment increased soil pH but had no effect on nodulation and BNF. Plant growth was affected by the soil and by the feedstock used for the “biochar”, and increased slightly more in treatments with pyrochar and hydrochar made from maize, which was richer in nitrogen and potassium.The results show that carbonized organic materials, and specifically hydrochar, have the capacity to increase BNF in soils. We suggest that this enhancement in BNF in response to soil amendments with carbonized organic materials is due to an increase in available sulfur and a reduction of available soil nitrogen.
RAFT Inverse Microemulsion Polymerization: Effects of Monomer Solubility and Different Types of Initiators
Authors: Oliveira Marco 
Published: March 2017

AbstractThe effects of monomer solubility and different types of initiators are for the first time reported for a reversible addition–fragmentation chain transfer (RAFT) inverse microemulsion polymerization system. 2‐(dimethylamino)ethyl methacrylate is selected as monomer due to its solubility in several solvents. A nonionic surfactant, cyclohexane, and a trithiocarbonyl RAFT chain transfer agent (CTA) are also used as main components. The reactions are performed adjusting the dispersed aqueous phase with selected pH values (5, 7, and 10), using an oil‐soluble or a water‐soluble initiator. In this microemulsion system, the RAFT process is especially influenced by the mono­mer content in the dispersed aqueous phase, directly related to the final pH. It is suggested that monomer diffusion and changes in the monomer/CTA ratio at the polymerization loci are the primary reasons for the different behaviors observed, specially those related to the molar mass properties.
image
Comparative study on the deformation behavior, structural evolution, and properties of biaxially stretched high‐density polyethylene/carbon nanofiller (carbon nanotubes, graphene nanoplatelets, and carbon black) composites
Authors: Xiang Dong , Wang Lei , Zhang Qingquan , Chen Biqiong , Li Yuntao , Harkin‐Jones Eileen 
Published: March 2017

In this article, a comparative study of biaxial stretching at different stretching ratios for melt mixed high‐density polyethylene (HDPE)/carbon nanofiller composites containing 4 wt% multiwalled carbon nanotubes (MWCNTs), graphene nanoplatelets (GNPs) or carbon black (CB) was conducted in order to investigate the influence of the carbon nanofillers on the processability of the material and on its final properties after processing. It is shown that the addition of carbon nanofillers results in a significant strain hardening behavior upon biaxial stretching, greatly improving the deformation stability and thus processability of the material. The reinforcement effectiveness of the nanofillers in strain hardening behavior is CB < MWCNTs < GNPs. The GNPs exhibit the most efficient reinforcement in modulus for the stretched samples, while the CB exhibits the most efficient reinforcement in tensile strength. Biaxial deformation destroys the conductive pathways of the nanofillers due to an increased interparticle distance and the destruction of nanofiller network structure. The MWCNT‐filled composites exhibit a more robust conductive network during stretching as a result of more interlacing or entanglement of the one‐dimensional nanotubes. The oxygen permeability coefficient of the material decreases significantly with the addition of GNPs, and which can be further reduced by two orders of magnitude after biaxial deformation due to the parallel alignment of two‐dimensional GNPs in the stretching plane. This study provides important information on the selection of carbon nanofillers for the processing and design of multifunctional polymer composites. POLYM. COMPOS., 39:E909–E923, 2018. © 2017 Society of Plastics Engineers
Optimization of preparation of thermally stable cellulose nanofibrils via heat‐induced conversion of ionic bonds to amide bonds
Authors: Lavoine Nathalie , Bras Julien , Saito Tsuguyuki , Isogai Akira 
Published: March 2017

ABSTRACTImproving the thermal stability of nanocelluloses is important for practical applications such as melt compounded nanocellulose‐reinforced polymer composites and flexible substrates for nanocellulose‐containing electronic devices. Here, we report optimum conditions for a straightforward surface modification strategy for improving the thermal stability of 2,2,6,6‐tetramethypiperidine‐1‐oxyl (TEMPO)‐oxidized cellulose nanofibrils (TOCNs); the heat‐induced conversion of TOCN alkyl ammonium carboxylates to amides. Different amine‐terminated compounds (R‐NH2) were grafted onto the surface of TOCNs under aqueous conditions. The influences of R‐NH2 molecular weight, R‐NH2/TOCN‐COOH molar ratio, and thermal stability of R‐NH2 on the properties of the grafted TOCN films were investigated through infrared spectroscopy and thermogravimetric analysis. For maximum thermal improvement of up to 90 °C, complete ionic bonding of TOCN carboxy groups with R‐NH2 was required, as well as proper selection of the R‐NH2 compound. A controlled heating process was also needed to achieve effective ionic‐to‐amide bond conversion. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1750–1756