bluuebunny/crossref_metadata_2025 huggingface dataset:
Linking Mitochondria and Synaptic Transmission: The CB1 Receptor
Authors: Djeungoue‐Petga Marie‐Ange , Hebert‐Chatelain Etienne
Published: October 2017

CB1 receptors are functionally present within brain mitochondria (mtCB1), although they are usually considered specifically targeted to plasma membrane. Acute activation of mtCB1 alters mitochondrial ATP generation, synaptic transmission, and memory performance. However, the detailed mechanism linking disrupted mitochondrial metabolism and synaptic transmission is still uncharacterized. CB1 receptors are among the most abundant G protein‐coupled receptors in the brain and impact on several processes, including fear coping, anxiety, stress, learning, and memory. Mitochondria perform several key physiological processes for neuronal homeostasis, including production of ATP and reactive oxygen species, calcium buffering, metabolism of neurotransmitters, and apoptosis. It is therefore possible that acute activation of mtCB1 impacts on these different mitochondrial functions to modulate synaptic transmission. In reviewing and integrating across the literature in this area, we describe the possible mechanisms involved in the regulation of brain physiology by mtCB1 receptors.
Enhanced red emission from BaMoO4: Eu3+ by Bi3+ co‐doping
Authors: Luo Wenqin , Ling Danping , Bao Susu , Xiong Huifang , Zhang Rui , Li Bin , Wu Haiyan
Published: October 2017

A series of Bi3+,Eu3+‐doped BaMoO4 phosphors was synthesized using a hydrothermal method. The crystal structure, morphology and optical properties of the phosphors were studied using X‐ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) measurements. Three different particle morphologies were detected in the SEM observation. The energy dispersive spectroscopy (EDS) results indicated that the solubility of Bi3+ in spherical or rugby‐like BaMoO4 particles was very low and the excess Bi3+ element was cumulated in the irregular particles. Characteristic emissions of Eu3+ ions (5D0 → 7FJ; J = 0, 1, 2, 3, 4) were observed under excitation in ultraviolet (UV) light, with the most intense transition being the 5D0 → 7F2 transition. Energy transfer from MoO42− and Bi3+ to Eu3+ can be readily achieved. Red emission intensity of Eu3+ was enhanced by a factor of two by co‐doping with a small amount of Bi3+. Optical properties as a function of Bi3+ content were studied and the optimum Bi3+ content in BaMoO4 nanocrystals was determined to be 0.4 mol%.
CRISPR/Cas9‐Based Counterselection Boosts Recombineering Efficiency in Pseudomonas putida
Authors: Aparicio Tomás , de Lorenzo Víctor , Martínez‐García Esteban
Published: October 2017

While adoption of single‐stranded DNA recombineering techniques has greatly eased genetic design of the platform strain Pseudomonas putida KT2440, available methods still produce the desired modifications/deletions at low frequencies. This makes isolation of mutants that do not display selectable or conspicuous phenotypes considerably difficult. To overcome this limitation, the authors have merged ssDNA recombineering with CRISPR/Cas9 technology in this bacterium for efficient killing of unmodified cells and thus non‐phenotypic selection of bacteria bearing the mutations of interest. After incorporating the system into standardized pSEVA plasmids the authors tested its functional efficiency by targeting different types of changes that ranged from single nucleotide substitutions to one‐gene deletions—to even the removal of the large flagellar cluster (≈69 kb). Simultaneous introduction of two independent gene deletions was tested as well. In all cases, directing the crRNA/Cas9 complexes toward non‐modified, wild‐type genomic sequences boosted dramatically the appearance of the mutants at stake in the absence of any phenotypic selection. The results presented here upgrade the engineering possibilities of the genome of this environmental bacterium (and possibly other Gram‐negatives) to obtain modifications that are otherwise cumbersome to generate.
Prognostic role of tumor necrosis in patients undergoing curative resection for gastric gastrointestinal stromal tumor: a multicenter analysis of 740 cases in China
Authors: Liu Xuechao , Qiu Haibo , Zhang Peng , Feng Xingyu , Chen Tao , Li Yong , Tao Kaixiong , Li Guoxin , Sun Xiaowei , Zhou Zhiwei ,   China Gastrointestinal Stromal Tumor Study Group (CN‐GIST)
Published: October 2017

Tumor necrosis is associated with poor clinical outcomes in many malignancies. We aimed to determine whether tumor necrosis was an independent predictor of outcomes in gastric gastrointestinal stromal tumors (GISTs). We retrospectively analyzed data from 740 patients undergoing curative resection for gastric GIST at four centers between 2001 and 2015. Disease‐free survival (DFS) was estimated with the Kaplan–Meier method, and associations with prognosis were assessed with Cox regression models. Tumor necrosis was present in 122 cases (16.5%). The prevalence of tumor necrosis increased with higher risk‐stratification, including 0.7%, 7.4%, 17.3%, and 39.3% for very low‐, low‐, intermediate‐ and high‐risk tumors, respectively (P < 0.001). Tumor necrosis was associated with aggressive tumor biology, such as larger tumor size, higher mitotic index, tumor rupture, and presence of nuclear atypia (all P < 0.05). Multivariate analysis revealed that tumor necrosis was an independent predictor of unfavorable DFS (HR: 2.641; 95% CI: 1.359–5.131; P = 0.004). When stratified by the modified National Institutes of Health (NIH) classification, tumor necrosis still independently predicted DFS in high‐risk patients (P = 0.001) but not in non‐high‐risk patients (P = 0.349). The 5‐year DFS rate in high‐risk patients with and without tumor necrosis was 56.5% and 82.9%, respectively (P = 0.004). Notably, the prognostic significance of tumor necrosis was maintained when the patients were stratified by age, sex, tumor location, tumor size, and mitotic index (All P < 0.05). Tumor necrosis is a useful predictor of outcomes in gastric GIST, especially in high‐risk patients. Based on these results, we recommend that the current NIH classification should be further improved and expanded to include tumor necrosis as a valuable prognostic indicator.
Hollow Porous Carbon with in situ Generated Monodisperse Gold Nanoclusters for Efficient CO Oxidation
Authors: Qu Jiafu , Zhu Haiguang , Chen Dongyun , Li Najun , Xu Qingfeng , Xie Jianping , Li Hua , He Jinghui , Lu Jianmei
Published: October 2017

Precious metals (Au and Pt) loaded in a mesoporous substrate (carbon and silicon) are popular materials for catalytic CO oxidation. However, the preparation of noble metals and the metal particle size after deposition in the pore channels of the mesoporous materials are serious issues for environmentally friendly applications. Herein, a gold‐decorated hollow porous carbon nanospheres (Au/HPCN) catalyst, which is both durable and uniform, is synthesized by a facile in situ reduction route for continuous CO oxidation. In our approach, HPCNs were selected as the substrate because of their thermal stability, well‐defined nanostructure, and large surface area. Au nanoclusters were loaded in the pore channels of HPCN because of their stability and catalytic performance. The as‐synthesized nanocomposite possesses a uniform size and highly porous structure. Moreover, CO oxidation occurred both during the reduction of Au3+ ions and after the preparation of Au/HPCN.
A Quantification of the Soai Reaction
Authors: Noble‐Terán María E. , Cruz José‐Manuel , Micheau Jean‐Claude , Buhse Thomas
Published: October 2017

A kinetic and thermodynamic model of the Soai reaction is presented. This allows the quantitative determination of five rates constants and one equilibrium constant. The model is realistic as it integrates the results of the most recently published XRD structural data and DFT calculations and selected experimental kinetic data. Equipped with the extracted parameters from the numerical fitting of the time evolution of both the substrate concentration and the enantiomeric excess, the model was able to mimic strong asymmetric amplification from extremely low initial enantiomeric excess and spontaneous mirror‐image symmetry breaking under “zero‐catalyst” conditions. It also reproduces the crystallization conditions by exhibiting the preferential accumulation of the corresponding oligomeric species in solution. An important point is also illustrated: the autocatalytic asymmetric amplification is not located on the expected easily detectable dimers but on the less concentrated tetrameric species.
The Applications of Metal−Organic Frameworks in Electrochemical Sensors
Authors: Liu Lantao , Zhou Yanli , Liu Shuang , Xu Maotian
Published: October 2017

Metal−organic frameworks (MOFs), synthesized by assembling metal nods with organic linkers, are highly ordered crystalline materials. MOFs have attracted much attention for applications in electrochemical sensors, because of their unique chemical and physical properties including ultrahigh porosity, large surface area, tunable structure, and high thermal and chemical stability. In particular, redox and catalytic active sites introduced by use of active metal ions and/or ligands endow MOFs with the functions required in electrochemical sensing. Moreover, precise chemical modification of functional molecules and immobilization with metal nanoparticles, carbon nanostructures, and biomolecules could promote their electrochemical performances. In this Review, we focus on recent progress achieved in MOF research with respect to general sensing principles and analytical performances of electrochemical sensors. The evaluation and challenges governing the detection of the assays are also discussed.
Electrochemical and Reactivity Studies of N→Sn Coordinated Distannynes
Authors: Novák Miroslav , Mikysek Tomáš , Růžička Aleš , Dostál Libor , Jambor Roman
Published: October 2017

Studies are focused on the redox potentials of N→Sn coordinated distannnynes {L1–3Sn}2 (L1=1, L2=2 and L3=3, in which L1 is [C6H3‐2,6‐(Me2NCH2)2]−, L2 is [C6H2‐2,4‐tBu2‐6‐(Et2NCH2)]− and L3 is [C6H2‐2,4‐tBu2‐6‐(DippN=CH)]−; Dipp=2,6‐diisopropylphenyl), containing the tin atom in oxidation state +I. Distannynes 1–3 were used as ligands for transition metals, and complexes [{L1Sn}2⋅Fe(CO)4] (4) and [{L2Sn}2⋅Fe(CO)4] (5) were prepared. The set of N→Sn coordinated distannynes 1–5 was studied by cyclic voltammetry measurements and the oxidation potentials of tin atoms in 1–5 were determined. The redox potentials are influenced by either ligands L1–3 or SnI→Fe coordination. Oxidation reactions of 1–3 were also studied. The reaction of 2 with (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) provided mixed organotin oxide {(L2SnO)(L2)Sn(μ‐O)}2 (6) as a consequence of the instability of the expected {L2Sn⋅TEMPO} complex. To support this proposed mechanism, the N→Ge coordinated digermyne {L2Ge}2 (7) was prepared. The reaction of 7 with TEMPO provided the expected complex {L2Ge⋅TEMPO} (8).
Phase Equilibrium of TiO2 Nanocrystals in Flame‐Assisted Chemical Vapor Deposition
Authors: Liu Changran , Camacho Joaquin , Wang Hai
Published: October 2017

Nano‐scale titanium oxide (TiO2) is a material useful for a wide range of applications. In a previous study, we showed that TiO2 nanoparticles of both rutile and anatase crystal phases could be synthesized over the size range of 5 to 20 nm in flame‐assisted chemical vapor deposition. Rutile was unexpectedly dominant in oxygen‐lean synthesis conditions, whereas anatase is the preferred phase in oxygen‐rich gases. The observation is in contrast to the 14 nm rutile–anatase crossover size derived from the existing crystal‐phase equilibrium model. In the present work, we made additional measurements over a wider range of synthesis conditions; the results confirm the earlier observations. We propose an improved model for the surface energy that considers the role of oxygen desorption at high temperatures. The model successfully explains the observations made in the current and previous work. The current results provide a useful path to designing flame‐assisted chemical vapor deposition of TiO2 nanocrystals with controllable crystal phases.
2D Spherulites of a Semi‐Fluorinated Alkane: Controlled Access to Either Radial Or Ring‐Banded Morphologies
Authors: Liu Xianhe , Mielke Salomé , Contal Christophe , Favier Damien , Yamamoto Akihisa , Tanaka Motomu , Krafft Marie Pierre
Published: October 2017

Thin films of a semi‐fluorinated alkane cast onto solid substrates consist of well‐formed two‐dimensional non‐birefringent ring‐banded and/or radial spherulites. Controlling the experimental conditions allows orientation of the crystallization toward either radial‐only or ring‐banded‐only morphologies. Intermediate states were also captured in which both radial and ring‐banded spherulites coexist. Monitoring of the formation of these intermediate states brought evidence for a first crystallization mode that sweeps radially outwards from a central nucleus until the propagating front edge experiences a second crystallization mode that proceeds through a diffusion‐controlled rhythmic crystallization mechanism that leads to high (≈2 μm) concentric ridges. These 2D spherulites were investigated by optical and atomic force microscopies, interferometric profilometry, and off‐specular neutron scattering.
Controlled Cortical Impact in the Rat
Authors: Dean Dana D. , Frank Joseph A. , Turtzo L. Christine
Published: October 2017

Traumatic brain injury (TBI) is a major cause of death and disability world‐wide. Following initial injury, TBI patients can face long‐term disability in the form of cognitive, physical, and psychological deficits, depending on the severity and location of injury. This results in an economic burden in the United States estimated to be $60 billion due to health‐care costs and loss of productivity. TBI is a significant area of active research interest for both military and civilian medicine. Numerous pre‐clinical animal models of TBI are used to characterize the anatomical and physiological pathways involved and to evaluate therapeutic interventions. Due to its flexibility and scalability, controlled cortical impact (CCI) is one of the most commonly used preclinical TBI models. This unit provides a basic CCI protocol performed in the rat. © 2017 by John Wiley & Sons, Inc.
Formal verification of a radio network random access protocol
Authors: Roumane Ahmed , Kechar Bouabdellah , Kouninef Belkacem
Published: October 2017

In this paper, the random access procedure of Universal Mobile Telecommunications System network is investigated. We have proposed a model based on communicating timed automata that represents the main functions related to the random access procedure including the user equipment, the base station (node B or BTS), and the channel. Then, we have used computational tree logic formula to specify the proprieties to be verified. The model and the formulas serve as inputs to the model checker, which is used as a verification engine, ie, UPPAAL and SPIN. The formal verification approach shows that the protocol has several drawbacks that may not be detected by simulation.
Cumulative effects of wildfires on forest dynamics in the eastern Cascade Mountains, USA
Authors: Reilly Matthew J. , Elia Mario , Spies Thomas A. , Gregory Matthew J. , Sanesi Giovanni , Lafortezza Raffaele
Published: October 2017

Wildfires pose a unique challenge to conservation in fire‐prone regions, yet few studies quantify the cumulative effects of wildfires on forest dynamics (i.e., changes in structural conditions) across landscape and regional scales. We assessed the contribution of wildfire to forest dynamics in the eastern Cascade Mountains, USA from 1985 to 2010 using imputed maps of forest structure (i.e., tree size and canopy cover) and remotely sensed burn severity maps. We addressed three questions: (1) How do dynamics differ between the region as a whole and the unburned portion of the region? (2) How do dynamics vary among vegetation zones differing in biophysical setting and historical fire frequency? (3) How have forest structural conditions changed in a network of late successional reserves (LSRs)? Wildfires affected 10% of forests in the region, but the cumulative effects at this scale were primarily slight losses of closed‐canopy conditions and slight gains in open‐canopy conditions. In the unburned portion of the region (the remaining 90%), closed‐canopy conditions primarily increased despite other concurrent disturbances (e.g., harvest, insects). Although the effects of fire were largely dampened at the regional scale, landscape scale dynamics were far more variable. The warm ponderosa pine and cool mixed conifer zones experienced less fire than the region as a whole despite experiencing the most frequent fire historically. Open‐canopy conditions increased slightly in the mixed conifer zone, but declined across the ponderosa pine zone even with wildfires. Wildfires burned 30% of the cold subalpine zone, which experienced the greatest increase in open‐canopy conditions and losses of closed‐canopy conditions. LSRs were more prone to wildfire than the region as a whole, and experienced slight declines in late seral conditions. Despite losses of late seral conditions, wildfires contributed to some conservation objectives by creating open habitats (e.g., sparse early seral and woodland conditions) that otherwise generally decreased in unburned landscapes despite management efforts to increase landscape diversity. This study demonstrates the potential for wildfires to contribute to regional scale conservation objectives, but implications for management and biodiversity at landscape scales vary geographically among biophysical settings, and are contingent upon historical dynamics and individual species habitat preferences.
Body size variation in aquatic consumers causes pervasive community effects, independent of mean body size
Authors: Carlson Bradley E. , Langkilde Tracy
Published: October 2017

Intraspecific phenotypic variation is a significant component of biodiversity. Body size, for example, is variable and critical for structuring communities. We need to understand how homogenous and variably sized populations differ in their ecological responses or effects if we are to have a robust understanding of communities. We manipulated body size variation in consumer (tadpole) populations in mesocosms (both with and without predators), keeping mean size and density of these consumers constant. Size‐variable consumer populations exhibited stronger antipredator responses (reduced activity), which had a cascading effect of increasing the biomass of the consumer's resources. Predators foraged less when consumers were variable in size, and this may have mediated the differential effects of predators on the community composition of alternative prey (zooplankton). All trophic levels responded to differences in consumer size variation, demonstrating that intrapopulation phenotypic variability can significantly alter interspecific ecological interactions. Furthermore, we identify a key mechanism (size thresholds for predation risk) that may mediate impacts of size variation in natural communities. Together, our results suggest that phenotypic variability plays a significant role in structuring ecological communities.
Strong positive effects of termites on savanna bird abundance and diversity are amplified by large herbivore exclusion
Authors: Moe Stein R. , Eldegard Katrine , Rannestad Ole Tobias , Okullo Paul , Lindtjørn Ommund , Støen Ole Gunnar , Dale Svein
Published: October 2017

Vast areas of the African savanna landscapes are characterized by tree‐covered Macrotermes termite mounds embedded within a relatively open savanna matrix. In concert with termites, large herbivores are important determinants of savanna woody vegetation cover. The relative cover of woody species has considerable effects on savanna function. Despite the potentially important ecological relationships between termite mounds, woody plants, large herbivores, and birds, these associations have previously received surprisingly little attention. We experimentally studied the effects of termites and large herbivores on the avian community in Lake Mburo National Park, Uganda, where woody vegetation is essentially limited to termite mounds. Our experiment comprised of four treatments in nine replicates; unfenced termite mounds, fenced mounds (excluding large mammals), unfenced adjacent savanna, and fenced savanna. We recorded species identity, abundance, and behavior of all birds observed on these plots over a two‐month period, from late dry until wet season. Birds used termite mounds almost exclusively, with only 3.5% of observations occurring in the treeless intermound savanna matrix. Mean abundance and species richness of birds doubled on fenced (large herbivores excluded) compared to unfenced mounds. Feeding behavior increased when large mammals were excluded from mounds, both in absolute number of observed individuals, and relative to other behaviors. This study documents the fundamental positive impact of Macrotermes termites on bird abundance and diversity in an African savanna. Birds play crucial functional roles in savanna ecosystems, for example, by dispersing fruits or regulating herbivorous insect populations. Thus, the role of birds in savanna dynamics depends on the distribution and abundance of termite mounds.
Seasonal genetic variation associated with population dynamics of a poecilogonous polychaete worm
Authors: Thonig Anne , Banta Gary Thomas , Hansen Benni Winding , Knott K. Emily
Published: October 2017

Poecilogonous species show variation in developmental mode, with larvae that differ both morphologically and ecologically. The spionid polychaete Pygospio elegans shows variation in developmental mode not only between populations, but also seasonally within populations. We investigated the consequences of this developmental polymorphism on the spatial and seasonal genetic structure of P. elegans at four sites in the Danish Isefjord‐Roskilde‐Fjord estuary at six time points, from March 2014 until February 2015. We found genetic differentiation between our sampling sites as well as seasonal differentiation at two of the sites. The seasonal genetic shift correlated with the appearance of new size cohorts in the populations. Additionally, we found that the genetic composition of reproductive individuals did not always reflect the genetic composition of the entire sample, indicating that variance in reproductive success among individuals is a likely explanation for the patterns of chaotic genetic patchiness observed during this and previous studies. The heterogeneous, unpredictable character of the estuary might maintain poecilogony in P. elegans as a bet‐hedging strategy in the Isefjord‐Roskilde‐Fjord complex in comparison with other sites where P. elegans are expected to be fixed to a certain mode of development.
Conservation of social effects (Ψ) between two species of Drosophila despite reversal of sexual dimorphism
Authors: Signor Sarah A. , Abbasi Mohammad , Marjoram Paul , Nuzhdin Sergey V.
Published: October 2017

Indirect genetic effects (IGEs) describe the effect of the genes of social partners on the phenotype of a focal individual. Here, we measure indirect genetic effects using the “coefficient of interaction” (Ψ) to test whether Ψ evolved between Drosophila melanogaster and D. simulans. We compare Ψ for locomotion between ethanol and nonethanol environments in both species, but only D. melanogaster utilizes ethanol ecologically. We find that while sexual dimorphism for locomotion has been reversed in D. simulans, there has been no evolution of social effects between these two species. What did evolve was the interaction between genotype‐specific Ψ and the environment, as D. melanogaster varies unpredictably between environments and D. simulans does not. In this system, this suggests evolutionary lability of sexual dimorphism but a conservation of social effects, which brings forth interesting questions about the role of the social environment in sexual selection.
A workflow of massive identification and application of intron markers using snakes as a model
Authors: Li Jiang‐Ni , He Chong , Guo Peng , Zhang Peng , Liang Dan
Published: October 2017

Relative to the commonly used mitochondrial and nuclear protein‐coding genes, the noncoding intron sequences are a promising source of informative markers that have the potential to resolve difficult phylogenetic nodes such as rapid radiations and recent divergences. Yet many issues exist in the use of intron markers, which prevent their extensive application as conventional markers. We used the diverse group of snakes as an example to try paving the way for massive identification and application of intron markers. We performed a series of bioinformatics screenings which identified appropriate introns between single‐copy and conserved exons from two snake genomes, adding particular constraints on sequence length variability and sequence variability. A total of 1,273 candidate intron loci were retrieved. Primers for nested polymerase chain reaction (PCR) were designed for over a hundred candidates and tested in 16 snake representatives. 96 intron markers were developed that could be amplified across a broad range of snake taxa with high PCR successful rates. The markers were then applied to 49 snake samples. The large number of amplicons was subjected to next‐generation sequencing (NGS). An analytic strategy was developed to accurately recover the amplicon sequences, and approximately, 76% of the marker sequences were recovered. The average p‐distances of the intron markers at interfamily, intergenus, interspecies, and intraspecies levels were .168, .052, .015, and .004, respectively, suggesting that they were useful to study snake relationships of different evolutionary depths. A snake phylogeny was constructed with the intron markers, which produced concordant results with robust support at both interfamily and intragenus levels. The intron markers provide a convenient way to explore the signals in the noncoding regions to address the controversies on the snake tree. Our improved strategy of genome screening is effective and can be applied to other animal groups. NGS coupled with appropriate sequence processing can greatly facilitate the extensive application of molecular markers.
Body macronutrient composition is predicted by lipid and not protein content of the diet
Authors: Moatt Joshua P. , Hambly Catherine , Heap Elizabeth , Kramer Anna , Moon Fiona , Speakman John R. , Walling Craig A.
Published: October 2017

Diet is an important determinant of fitness‐related traits including growth, reproduction, and survival. Recent work has suggested that variation in protein:lipid ratio and particularly the amount of protein in the diet is a key nutritional parameter. However, the traits that mediate the link between dietary macronutrient ratio and fitness‐related traits are less well understood. An obvious candidate is body composition, given its well‐known link to health. Here, we investigate the relationship between dietary and body macronutrient composition using a first‐generation laboratory population of a freshwater fish, the three‐spine stickleback (Gasterosteus aculeatus). Carbohydrate is relatively unimportant in the diet of predatory fish, facilitating the exploration of how dietary protein‐to‐lipid ratio affects their relative deposition in the body. We find a significant effect of lipid intake, rather than protein, on body protein:lipid ratio. Importantly, this was not a result of absorbing macronutrients in relation to their relative abundance in the diet, as the carcass protein:lipid ratios differed from those of the diets, with ratios usually lower in the body than in the diet. This indicates that individuals can moderate their utilization, or uptake, of ingested macronutrients to reach a target balance within the body. We found no effect of diet on swimming endurance, activity, or testes size. However, there was an effect of weight on testes size, with larger males having larger testes. Our results provide evidence for the adjustment of body protein:lipid ratio away from that of the diet. As dietary lipid intake was the key determinant of body composition, we suggest this occurs via metabolism of excess protein, which conflicts with the predictions of the protein leverage hypothesis. These results could imply that the conversion and excretion of protein is one of the causes of the survival costs associated with high‐protein diets.
Water‐Dispersible Boron Nitride Nanospheres with High Thermal Conductivity for Heat‐Transfer Nanofluids
Authors: Han Weifang , Wang Lixia , Zhang Rui , Ge Chunhua , Ma Zhiyan , Yang Yuxuan , Zhang Xiangdong
Published: October 2017

The low dispersion stability of hexagonal boron nitride (h‐BN) materials in aqueous solutions restricts their further application. Functionalization has been demonstrated as a promising way to solve this problem. However, functionalized BN is difficult to disperse and stabilize in water at high concentrations. Herein, we have developed water‐dispersible BN nanospheres without requiring modification or the addition of surfactants. The lower‐temperature heat treatment of the HTC@H3BO3·C3N6H6 (boric acid–melamine‐wrapped carboxyl‐rich hydrothermal carbon sphere) precursors during the pyrolysis process resulted in a high oxygen content on the surface of the BN, which prominently increased the charge on the surface of the BN nanospheres and thus improved the dispersion stability of BN in water. The as‐prepared BN nanospheres, with a diameter of 550 nm, have high yield, high surface area (316.77 m2 g–1), and large pore volume (0.65 cm3 g–1). In particular, the thermal conductivity of the water‐based fluid was significantly enhanced by 55 % at 0.10 vol.‐% of BN nanospheres. Moreover, BN–water nanofluids exhibited excellent long‐term stability. These results suggest that the as‐obtained BN nanospheres have broad prospects in improving the thermal conductivity of water‐based fluids.
Integrative Theory/Experiment‐Driven Exploration of a Multicomponent Reaction towards Imidazoline‐2‐(thi)ones
Authors: Kruithof Art , Mulder Jos R. , Ruiz J. M. , Janssen Elwin , Mooijman M. , Ruijter Eelco , Fonseca Guerra Célia , Bickelhaupt F. Matthias , Orru Romano V. A.
Published: October 2017

Predicting reactivity in multicomponent reactions (MCRs) is extremely difficult. These reactions proceed by multiple pathways and are inherently associated with a potentially large variation of reactants and functional groups. To date, theoretical chemistry has been used in hindsight to verify experimental observations. However, its use in the early stages of the development of a (multicomponent) reaction process can prevent laborious and time‐consuming optimization studies by pinpointing the most relevant parameter(s) in the reactivity, thus focusing experimental efforts. Herein, we discuss a study that truly integrates theoretical and synthetic chemistry to unravel in full detail the complex and intricate reaction characteristics of the novel versatile MCR of α‐acidic iso(thio)cyanates, amines and aldehydes to access densely functionalized imidazoline‐2‐(thi)ones.
A Novel Eutectic Mixture of Biphenyl and Diphenylmethane as a Potential Liquid Organic Hydrogen Carrier: Catalytic Hydrogenation
Authors: Han Da Jung , Jo Young Suk , Shin Byeong Soo , Jang Munjeong , Kang Jeong Won , Han Jong Hee , Nam Suk Woo , Yoon Chang Won
Published: October 2017

A novel, liquid‐phase hydrogen storage material was produced by mixing biphenyl (C12H10, solid) and diphenylmethane (C13H12, liquid) with a mass ratio (wt %) of 35:65. The eutectic mixture was proved to be liquid at ambient temperature with a viscosity of 3.0 cP at 25 °C and a vapor pressure of 1.4 Pa at 25 °C, which potentially meets the requirements for an efficient hydrogen storage system. A theoretical study using COSMO‐RS method further confirms that an optimum composition of biphenyl and diphenylmethane for the formation of eutectic mixture is 37:63 by mass, which is very close to the composition found experimentally. The eutectic mixture exhibited a superior activity for hydrogenation reactions conducted at 120 °C under 50 bar of H2 pressure in the presence of a Ru (5 wt %)/Al2O3 catalyst. Hydrogen uptake of the eutectic mixture tested was close to full conversion, which corresponds to 6.9 wt % and 60.1 g L−1 of gravimetric and volumetric hydrogen storage capacities, respectively.
Ketogenic parenteral nutrition in 17 pediatric patients with epilepsy
Authors: Dressler Anastasia , Haiden Nadja , Trimmel‐Schwahofer Petra , Benninger Franz , Samueli Sharon , Gröppel Gudrun , Spatzierer Sina , Mühlebner Angelika , Abraham Klaus , Feucht Martha
Published: October 2017

Objective

Ketogenic parenteral nutrition (kPN) is indicated when enteral intake is temporarily limited or impossible, but evidence‐based prescriptions are lacking. Objective was to evaluate the efficacy and safety of kPN in children with epileptic encephalopathies using a new computer‐based algorithm for accurate component calculating.

Methods

Children with epilepsy receiving kPN were included. A computer‐based algorithm was established on the basis of guidelines of the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN): fat intake not exceeding 4 g/kg/day, age‐adequate supply of protein, electrolytes, vitamins, and trace elements, but reduced carbohydrates. Primary outcome was successfully reaching relevant ketosis, defined as beta‐hydroxybutyrate plasma level of ≥ 2 mmol/L. Efficacy was defined as seizure reduction ≥50% in de novo kPN and maintenance of response in children already on a ketogenic diet (KD). Safety was assessed by adverse effects, laboratory findings, and the appropriateness of nutritional intake.

Results

Seventeen children (median 1.84 years) were studied, of which 76% (13/17) were already on an oral ketogenic diet. Indications for kPN were surgery, status epilepticus, vomiting, food refusal, and introduction of enteral feeding in neonates. The parenteral fat/nonfat ratio was mean 0.9 (±0.3; range 0.6–1.5). Relevant ketosis was reached in 10 children (median 2.9 mmol/L), but not in 7 (median = 1.4 mmol/L). In de novo kPN, significant response was observed in 50% (2/4); in patients previously responding to the KD (77%, 10/13), response was maintained. A significant correlation between the degree of ketosis and seizure reduction (correlation coefficient = 0.691; p = .002) was observed. Only mild and transient adverse events occurred during kPN.

Significance

KPN with fat intake of 3.5–4.0 g/kg/day was safe and effective. KPN was tailored according to guidelines and individual nutritional needs. In nearly half of the patients, ketosis was lower than during oral KD. Despite this, seizures remained controlled.
Radiation‐induced brain structural and functional abnormalities in presymptomatic phase and outcome prediction
Authors: Ding Zhongxiang , Zhang Han , Lv Xiao‐Fei , Xie Fei , Liu Lizhi , Qiu Shijun , Li Li , Shen Dinggang
Published: October 2017

Radiation therapy, a major method of treatment for brain cancer, may cause severe brain injuries after many years. We used a rare and unique cohort of nasopharyngeal carcinoma patients with normal‐appearing brains to study possible early irradiation injury in its presymptomatic phase before severe, irreversible necrosis happens. The aim is to detect any structural or functional imaging biomarker that is sensitive to early irradiation injury, and to understand the recovery and progression of irradiation injury that can shed light on outcome prediction for early clinical intervention. We found an acute increase in local brain activity that is followed by extensive reductions in such activity in the temporal lobe and significant loss of functional connectivity in a distributed, large‐scale, high‐level cognitive function‐related brain network. Intriguingly, these radiosensitive functional alterations were found to be fully or partially recoverable. In contrast, progressive late disruptions to the integrity of the related far‐end white matter structure began to be significant after one year. Importantly, early increased local brain functional activity was predictive of severe later temporal lobe necrosis. Based on these findings, we proposed a dynamic, multifactorial model for radiation injury and another preventive model for timely clinical intervention. Hum Brain Mapp 39:407–427, 2018. © 2017 Wiley Periodicals, Inc.
Predicting auditory feedback control of speech production from subregional shape of subcortical structures
Authors: Tang Xiaoying , Chen Na , Zhang Siyun , Jones Jeffery A. , Zhang Baofeng , Li Jingyuan , Liu Peng , Liu Hanjun
Published: October 2017

Although a growing body of research has focused on the cortical sensorimotor mechanisms that support auditory feedback control of speech production, much less is known about the subcortical contributions to this control process. This study examined whether subregional anatomy of subcortical structures assessed by statistical shape analysis is associated with vocal compensations and cortical event‐related potentials in response to pitch feedback errors. The results revealed significant negative correlations between the magnitudes of vocal compensations and subregional shape of the right thalamus, between the latencies of vocal compensations and subregional shape of the left caudate and pallidum, and between the latencies of cortical N1 responses and subregional shape of the left putamen. These associations indicate that smaller local volumes of the basal ganglia and thalamus are predictive of slower and larger neurobehavioral responses to vocal pitch errors. Furthermore, increased local volumes of the left hippocampus and right amygdala were predictive of larger vocal compensations, suggesting that there is an interplay between the memory‐related subcortical structures and auditory‐vocal integration. These results, for the first time, provide evidence for differential associations of subregional morphology of the basal ganglia, thalamus, hippocampus, and amygdala with neurobehavioral processing of vocal pitch errors, suggesting that subregional shape measures of subcortical structures can predict behavioral outcome of auditory‐vocal integration and associated neural features. Hum Brain Mapp 39:459–471, 2018. © 2017 Wiley Periodicals, Inc.
The bumps under the hippocampus
Authors: Chang Cheng , Huang Chuan , Zhou Naiyun , Li Shawn Xiang , Ver Hoef Lawrence , Gao Yi
Published: October 2017

Shown in every neuroanatomy textbook, a key morphological feature is the bumpy ridges, which we refer to as hippocampal dentation, on the inferior aspect of the hippocampus. Like the folding of the cerebral cortex, hippocampal dentation allows for greater surface area in a confined space. However, examining numerous approaches to hippocampal segmentation and morphology analysis, virtually all published 3D renderings of the hippocampus show the inferior surface to be quite smooth or mildly irregular; we have rarely seen the characteristic bumpy structure on reconstructed 3D surfaces. The only exception is a 9.4T postmortem study (Yushkevich et al. [2009]: NeuroImage 44:385–398). An apparent question is, does this indicate that this specific morphological signature can only be captured using ultra high‐resolution techniques? Or, is such information buried in the data we commonly acquire, awaiting a computation technique that can extract and render it clearly? In this study, we propose an automatic and robust super‐resolution technique that captures the fine scale morphometric features of the hippocampus based on common 3T MR images. The method is validated on 9.4T ultra‐high field images and then applied on 3T data sets. This method opens possibilities of future research on the hippocampus and other sub‐cortical structural morphometry correlating the degree of dentation with a range of diseases including epilepsy, Alzheimer's disease, and schizophrenia. Hum Brain Mapp 39:472–490, 2018. © 2017 Wiley Periodicals, Inc.
Novel self‐gelling injectable hydrogel/alpha‐tricalcium phosphate composites for bone regeneration: Physiochemical and microcomputer tomographical characterization
Authors: Douglas Timothy E. L. , Schietse Josefien , Zima Aneta , Gorodzha Svetlana , Parakhonskiy Bogdan V. , KhaleNkow Dmitry , Shkarin Roman , Ivanova Anna , Baumbach Tilo , Weinhardt Venera , Stevens Christian V. , Vanhoorne Valérie , Vervaet Chris , Balcaen Lieve , Vanhaecke Frank , Slośarczyk Anna , Surmeneva Maria A. , Surmenev Roman A. , Skirtach Andre G.
Published: October 2017

Mineralized hydrogels are increasingly gaining attention as biomaterials for bone regeneration. The most common mineralization strategy has been addition of preformed inorganic particles during hydrogel formation. This maintains injectability. One common form of bone cement is formed by mixing particles of the highly reactive calcium phosphate alpha‐tricalcium phosphate (α‐TCP) with water to form hydroxyapatite (HA). The calcium ions released during this reaction can be exploited to crosslink anionic, calcium‐binding polymers such as the polysaccharide gellan gum (GG) to induce hydrogel formation. In this study, three different amounts of α‐TCP particles were added to GG polymer solution to generate novel, injectable hydrogel‐inorganic composites. Distribution of the inorganic phase in the hydrogel was studied by high resolution microcomputer tomography (µCT). Gelation occurred within 30 min. α‐TCP converted to HA. µCT revealed inhomogeneous distribution of the inorganic phase in the composites. These results demonstrate the potential of the composites as alternatives to traditional α‐TCP bone cement and pave the way for incorporation of biologically active substances and in vitro and in vivo testing. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 822–828, 2018.
Mesoderm‐specific transcript localization in the ER and ER‐lipid droplet interface supports a role in adipocyte hypertrophy
Authors: Prudovsky Igor , Anunciado‐Koza Rea P. , Jacobs Chester G. , Kacer Doreen , Siviski Matthew E. , Koza Robert A.
Published: October 2017

Highly variable expression of mesoderm‐specific transcript (Mest) in adipose tissue among genetically homogeneous mice fed an obesogenic diet, and its positive association with fat mass expansion, suggests that Mest is an epigenetic determinant for the development of obesity. Although the mechanisms by which MEST augments fat accumulation in adipocytes have not been elucidated, it has sequence homology and catalytic peptide motifs which suggests that it functions as an epoxide hydrolase or as a glycerol‐ or acylglycerol‐3‐phosphate acyltransferase. To better understand MEST function, detailed studies were performed to precisely define the intracellular organelle localization of MEST using immunofluorescence confocal microscopy. Lentiviral‐mediated expression of a C‐terminus Myc‐DDK‐tagged MEST fusion protein expressed in 3T3‐L1 preadipocytes/adipocytes, and ear‐derived mesenchymal stem cells (EMSC) from mice was observed in the endoplasmic reticulum (ER) membranes and is consistent with previous studies showing endogenous MEST in the membrane fraction of adipose tissue. MEST was not associated with the Golgi apparatus or mitochondria; however, frequent contacts were observed between MEST‐positive ER and mitochondria. MEST‐positive domains were also shown on the plasma membrane (PM) of non‐permeabilized cells but they did not co‐localize with ER‐PM bridges. Post‐adipogenic differentiated 3T3‐L1 adipocytes and EMSC showed significant co‐localization of MEST with the lipid droplet surface marker perilipin at contact points between the ER and lipid droplet. Identification of MEST as an ER‐specific protein that co‐localizes with lipid droplets in cells undergoing adipogenic differentiation supports a function for MEST in the facilitation of lipid accumulation and storage in adipocytes.
Retracted: MicroRNA‐103 confers the resistance to long‐treatment of adriamycin to human leukemia cells by regulation of COP1
Authors: Wan Lin , Tian Yanlong , Zhang Rui , Peng Zhuo , Sun Jiangli , Zhang Wanggang
Published: October 2017

Adriamycin (ADR) is an anti‐cancer drug which offers improvement in survival for acute myeloid leukemia (AML) patients. However, the drug resistance is almost inevitable. Increasing evidences suggested that microRNAs (miRNAs) were associated with cancer chemo‐resistance. Here, we aimed to explore the possible mechanism of miR‐103 affected resistance to ADR in AML cells. Different concentrations of ADR were used to induce K562 and KASUMI‐1 cells, and miR‐103 mimic, inhibitor were transfected into K562 and KASUMI‐1 cells. Cell viability and proliferation were determined by trypan blue staining and MTT assays for evaluating K562 and KASUMI‐1 cells drug resistance. The relationship of miR‐103 and COP1, Trib1, and C/EBPα were analyzed by qRT‐PCR and Western blot. Cell proliferation, viability were detected again. Besides, the expressions of main factors of cell cycle and PI3K/AKT signal pathway were analyzed by Western blot. Results showed that ADR inhibited cell viability and proliferation in K562 and KASUMI‐1 cells. However, K562 and KASUMI‐1 cells appeared drug resistance for 50 passages at 0.8 µM of ADR. In addition, miR‐103 expression was up‐regulated in ADR‐resistant K562 cells (K562/ADR) and overexpression of miR‐103 increased K562 cells drug resistance via promoting cell viability and cell cycle‐related factors expressions. COP1 was positively regulated by miR‐103, suppression of miR‐103 recovered K562/ADR cells drug resistance by regulation of COP1, Trib1, and C/EBPα. Besides, miR‐103 blocked PI3K/AKT signal pathway by regulation of COP1. These data indicated that miR‐103 was up‐regulated in drug resistant cells and it may regulate ADR‐resistance by regulation of COP1 in AML cells.
The effects of Curcumin on HCT‐116 cells proliferation and apoptosis via the miR‐491/PEG10 pathway
Authors: Li Bai , Shi Chong , Li Bo , Zhao Jing‐Ming , Wang Lei
Published: October 2017

Paternally expressed gene‐10 (PEG10) could participate in several carcinomas and might be regulated by miR‐491. To now, miR‐491 was found to play an important role in the sensitivity and mechanism of drug usage in the treatment of colorectal cancer, and drug resistance is a key factor to affect the disease healing. In this study, miR‐491, PEG10, Wnt1, and β‐catenin expression levels and their correlation with colorectal cancer were assessed in cancer tissues and adjacent parts. And the target relationship between PEG10 and miR‐491 was verified. Meanwhile, the impaction of Curcumin on miR‐491, PEG10, and Wnt/β‐catenin signaling pathway were analyzed in HCT‐116 cells. The effects of PEG10 and Curcumin on human HCT‐116 cells proliferation and apoptosis were investigated by MTT and flow cytometry assay. Results showed that the expression of miR‐491 in colon cancer tissues was decreased, but PEG10, Wnt1, and β‐catenin were higher than that in adjacent tissues. The PEG10 gene 3′ UTR could combine with miR‐491 seed sequence and miR‐491 overexpression could cause a decrease in PEG10, Wnt1, and β‐catenin levels in human HCT‐116 cells. Furthermore, PEG10 overexpression increased the expression levels of Wnt1 and β‐catenin, thereby promoting cell proliferation and inhibiting apoptosis. In addition, Curcumin could up‐regulate miR‐491, inhibit PEG10, and Wnt/β‐catenin signaling pathway. Consequently, Curcumin reduced HCT‐116 cells proliferation and promoted cells apoptosis via the miR‐491/PEG10 pathway. In conclusion, PEG10 was a target gene of miR‐491, miR‐491/PEG10 strengthen the sensitivity of Curcumin in HCT‐116 cells proliferation and apoptosis, which might act as an ideal diagnostic biomarker treatment methods.