bluuebunny/crossref_metadata_2025 huggingface dataset:
Normal spermatogenesis in Fank1 (fibronectin type 3 and ankyrin repeat domains 1) mutant mice
Authors: Zhang Jintao , Zhang Xin , Zhang Yue , Zeng Wentao , Zhao Shuqin , Liu Mingxi
Published: November 2018

Background. The fibronectin type 3 and ankyrin repeat domains 1 gene, Fank1, is an ancient, evolutionarily conserved gene present in vertebrates. Fank1-knockdown mice have oligospermia caused by an increase in apoptotic germ cells. In this study, we investigated the in vivo function of Fank1.

Methods. In this study, we generated Fank1-knockout mice using the CRISPR/Cas9 system. We then investigated the phenotype and in vivo function of Fank1. Testes and epididymis tissues were analyzed by histological and immunofluorescence staining. Apoptotic cells were analyzed in TUNEL assays. Fertility and sperm counts were also evaluated. The GTEx database were used to assess gene expression quantitative trait loci (eQTL) and mRNA expression of candidate genes and genes neighboring single nucleotide polymorphisms was analyzed by quantitative RT-PCR.

Results. In contrast to the Fank1-knockdown model, no significant changes in epididymal sperm content and the number of apoptotic cells were observed in Fank1-/- homozygotes. In addition, a different pattern of Dusp1, Klk1b21 and Klk1b27 mRNA expression was detected in Fank1-knockout testis. These results reveal differences in the molecular changes between Fank1-knockdown mice and Fank1 -knockout mice and provide a basic resource for population genetics studies.
Bubble growth model and its influencing factors in a polymer melt under nonisothermal conditions
Authors: Zhang Yun , Xin Chunling , Li Xiaohu , Waqas Mughal , He Yadong
Published: November 2018

Traditionally, in order to simplify the bubble growth process in a polymer melt, an isothermal model is typically used. In fact, the temperature of the polymer melt is changing during the foaming process. In order to accurately study the growth mechanism of bubbles in polymer melts, we build a physical and mathematical model of bubble growth in a polymer melt under nonisothermal conditions. The parameters of pressure, zero‐shear viscosity, relaxation time, Henry's constant, diffusion coefficient, and surface tension were determined. The fourth‐order Runge–Kutta method was used to solve the nonisothermal bubble model in the polymer melt. A computational program is developed to find the dimensional change during the bubble growth process, and the correctness of the model is verified. The nonisothermal growth mechanism of and factors influencing bubbles in the polymer melt are analyzed. Combined with the design of experiment (DOE) analysis method, the transfer function of the bubble radius and the maximum growth rate of bubbles with the process parameters were obtained, such as cooling rate, system pressure, and gas concentration. The results show that system pressure has the most significant effect on bubble growth. At the same time, a bubble growth prediction model is built, which can be used to predict the growth of bubbles. Through optimization analysis, it can be used to control the growth of bubbles. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47210.
Metal‐phenolic networks: A biobased synergist for EVA/APP composites toward enhanced thermal stability and flame retardancy
Authors: Hu Zai‐Yin , Xu Shimei , Zhao Hai‐Bo , Wang Yu‐Zhong
Published: November 2018

In the present study, a biomass‐derived metal‐phenolic networks (MPN) were used as charring agent and flame‐retardant synergist for Ethylene‐vinyl acetate/Ammonium polyphosphate (EVA/APP) composites. Compared with the polyphenol, the thermal stability of MPN was improved remarkably, making it a good match for EVA. Meanwhile, Limit oxygen index test revealed that MPN endowed EVA/APP composites with enhanced flame‐retardant performance. The reason on improvement in the flame retardancy of composites was also discussed and the corresponding mechanism was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47243.
Polyphenols assisted silica coating on polypropylene separators with improved wettability and heat‐resistance for lithium‐ion batteries
Authors: Yuan Jia‐Jia , Song You‐Zhi , Zhang Yin , Qiu Ze‐Lin , Sun Chuang‐Chao , Yin Xue , Zhu Li‐Ping , Zhu Bao‐Ku
Published: November 2018

The separator, as one of the essential components for lithium‐ion batteries (LIBs), has garnered considerable attention because of its significant role in battery performance. Here, an in‐situ coating method to promote the wettability and thermal‐stability of polypropylene (PP) separators was reported. The separator was first dip‐coated with phenolic compound based on biologically inspired surface modification. Then silica layers were in‐situ formed on the separator via a sol–gel process of silicate solution, so that an inorganic–organic hybrid layer was coated on PP separators without the need of any polymer binders. Besides, this method hardly increases the film thickness or sacrifices microporous structure of the pristine separator. Due to the introduction of hybrid layers, the resulted separators showed excellent dimensional thermostability, as the thermal shrinkage was only 20% at 150 °C while that of the bare separator was about 80%. Meanwhile, electrochemical performances of cells with the modified separator were obviously improved, especially the rate performance. At the charge/discharge current density of 5 C, cells with PP separators nearly lost all the capacity, but the modified separator still held 45.7% of the discharge capacity at 0.2 C. This facile yet effective method has great application prospects in the preparation of ceramic‐coated separators. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47277.
A novel cyclic copolymer containing Si/P/N used as flame retardant and water repellent agent on cotton fabrics
Authors: Wei Dongdong , Dong Chaohong , Chen Zhaohua , Liu Jian , Li Qun , Lu Zhou
Published: November 2018

A novel cyclic‐shaped multifunctional copolymer named poly[tetra(tetramethylcyclosiloxyl‐piperazin)‐phosphinic acid methyl ether] (PNCTSi) was successfully synthesized. Its flame‐retardant and hydrophobicity properties on cotton fabrics were investigated. The limited oxygen index (LOI) value of treated cotton fabrics with PNCTSi was up to 29.8%. By vertical burning test, it was found that the treated cotton fabrics have no after‐flame and no after‐glow. Apparently, more amounts of char were generated and hazardous volatiles distinctly reduce after combustion by thermogravimetric analysis. Besides, Treated cotton fabrics with PNCTSi can give a hydrophobic property, which reach a contact angle of 150°. The surface morphology of treated cotton fabric before and after combustion was analyzed by scanning electron microscopy, after burned, the surface morphology of cotton fiber exhibited more smooth and expanded feature. After washing the cotton fabric for 20 times, the LOI remains at above of 26.0%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47280.
Structural, mechanical, and antibacterial features of curcumin/polyurethane nanocomposites
Authors: Marković Zoran , Kováčová Mária , Mičušík Matej , Danko Martin , Švajdlenková Helena , Kleinová Angela , Humpolíček Petr , Lehocký Marián , Marković Biljana Todorović , Špitalský Zdeno
Published: November 2018

Various types of bacteria inhabit many surfaces thus causing problems which can have very strong impact on human health. Here we present a study of photophysical, mechanical, and antibacterial properties of curcumin/polyurethane nanocomposites prepared by swell‐encapsulation‐shrink method. The prepared nanocomposites have been characterized for degree of swelling, surface morphology, mechanical properties, chemical contents, photoluminescence, hydrophobicity, potentials for singlet oxygen generation, and antibacterial activity. Dynamic mechanical analysis has shown slight changes of glass temperature of curcumin/polyurethane nanocomposites due to blue light irradiation. It was found that nanocomposites have very strong photoluminescence, become photoactive upon blue light irradiation at 470 nm and generate singlet oxygen. Conducted antibacterial tests have shown very strong activity of these nanocomposites especially toward Escherichia coli. These bacteria strains have been eliminated completely only after 1 h irradiation by blue light. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47283.
Influence of co‐monomer‐type and amount on thermomechanical properties of ultrafast‐curing acrylic resins using a triacrylic crosslinker
Authors: Böhm Michael , Ruhland Klaus , Koch Marius , Spalek Niclas
Published: November 2018

An ultrafast ultraviolet‐light‐cured acrylic resin was developed. The monoacrylic monomers ethylene‐glycol‐phenyl‐ether acrylate (EGPEA), 2‐hydroxy‐3‐phenoxypropyl acrylate (HPPA), di(ethyleneglycol)‐ethyl‐ether acrylate (DEGEEA), or poly(ethyleneglycol)‐phenyl‐ether acrylate (PolyEGPEA) were each mixed with varying amounts of the triacrylic crosslinker tris[2‐(acryloyloxy)ethyl] isocyanurate (ICTA). The curing time was 1 s at room temperature (average degrees of curing between 55 and 85%). The specimens of ICTA‐EGPEA showed a maximum tensile strength of 76.0 ± 1.4 MPa, an E‐modulus of 4216 ± 188 MPa, an elongation at break of 2.3 ± 0.1%, and a glass transition temperature (T
g) of 100 °C. The development of properties with increasing amount of crosslinker could be well described on the basis of percolation theory. Below the percolation threshold the behavior is dominated by the auxiliary co‐monomer. Above the percolation threshold the behavior is dominated by ICTA. On exchanging EGPEA by HPPA, the influence of hydrogen bonding on the thermomechanical properties was extracted. Exchanging EGPEA by DEGEEA or PolyEGPEA allowed for exploring the influence of beta‐relaxation of the monoacrylic monomers on the thermomechanical properties of the resin. Large ester side‐groups reduced the tensile strength, the E‐modulus, and the T
g decisively. The impact strength in turn was decisively increased using PolyEGPEA as auxiliary co‐monomer. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47294.
Enhancement of drawdown force in polypropylene containing nucleating agent
Authors: Phulkerd Panitha , Nakabayashi Takehiro , Iwasaki Shohei , Yamaguchi Masayuki
Published: November 2018

The effect of the nucleation efficiency of three commercial nucleating agents, such as 1,3:2,4‐bis(3,4‐dimethylbenzylidene)sorbitol (DMDBS), sodium 2,2′‐methylene‐bis‐(4,6‐di‐tert‐butylphenyl)phosphate (SMBP), and magnesium silicate (talc), on the melt‐stretching performance of isotactic polypropylene (PP) is studied. It is found that the addition of 0.5 wt % of a nucleating agent enhances the crystallization temperature and that effect is pronounced for DMDBS and SMBP. Furthermore, DMDBS is more efficient than the other tested nucleating agents in enhancing the drawdown force, defined as a force required for stretching a molten strand. Nanofibers of DMDBS, which show significant alignment in the flow direction, are responsible for the rapid crystallization of PP in the flow field leading to an increase of drawdown force. The stretched strand shows a highly oriented structure in which the α‐form crystals orient to the flow direction. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47295.
Utilization of different tall oils for improving the water resistance of cellulosic fibers
Authors: Hosseinpourpia Reza , Adamopoulos Stergios , Parsland Charlotte
Published: November 2018

This study was conducted to assess the effect of the pulping by‐products crude tall oil (CTO), distilled tall oil (DTO), and tall oil fatty acid (TOFA) on dynamic water vapor sorption behavior, interfiber strength, and thermal stability of cellulosic paper‐sheets. The results were compared against those obtained in cellulose papers treated with the conventional petroleum‐derived hydrophobic agent hydrowax and in untreated ones. The tall oil treatments caused strong reduction in equilibrium moisture content of the paper‐sheets during adsorption and desorption runs. The same trend was noticed for the hydrowax‐treated papers, however, it was less pronounced than the CTO‐treated and DTO‐treated samples in the relative humidity range of 75–95%. The sorption hysteresis was considerably decreased after the treatments. The ultimate dry‐tensile strengths of the paper‐sheets were significantly reduced by TOFA and hydrowax treatments, while CTO and DTO showed comparable strength as that of untreated control. The ultimate wet‐strengths of the paper‐sheets were improved after the treatments. The thermal stability of the specimens was improved by the tall oil treatments, and the hydrowax‐treated samples illustrated lower degradation temperature than the untreated control. The results are promising for the use of tall oils as alternative hydrophobic agents of cellulosic fiber‐based products, such as wood panels and paper packaging. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47303.
Polydimethylsiloxane–PbZr0.52Ti0.48O3 nanocomposites with high permittivity: Effect of poling and temperature on dielectric properties
Authors: Nayak Suryakanta , Khastgir Dipak
Published: November 2018

Polydimethylsiloxane (PDMS)/lead zirconate titanate (PbZr0.52Ti0.48O3, PZT)‐based nanocomposites with high dielectric constant (permittivity, k) are prepared through room temperature mixing. The effect of PZT loading on electrical and mechanical properties of the PDMS–PZT composites is extensively studied. It is found that there is significant increase in permittivity with PZT loading and decrease in volume resistivity. All the composites have low dielectric loss compared to permittivity value. It is observed that there is increase in permittivity and decrease in volume resistivity of composites after poling, which is due to the dipolar polarization. It is found that both permittivity (ε′) and alternating current conductivity (σac) are increased with temperature at low frequency (1 Hz) and decreased with temperature at high frequency (1 MHz). The above composites are sensitive to external pressure and can be used as pressure/force sensor. The tensile strength and % elongation at break decreases with PZT loading, which is due to the nonreinforcing behavior of PZT ceramic. PZT particles distribution and dispersion in PDMS matrix are observed through field emission scanning electron microscopy, high resolution transmission electron microscopy, and atomic force microscopy/scanning probe microscopy. Thermal stability of composites increased with the PZT loading which is due to higher thermal stability of PZT particles compared to PDMS matrix. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47307.
Heat resistance of acrylic pressure‐sensitive adhesives based on commercial curing agents and UV/heat curing systems
Authors: Zhang Xiaoyong , He Jinmei , Yue Lipei , Bai Yongping , Liu Huihui
Published: November 2018

The development of adhesive tapes that can be applied at high temperature is a major challenge for pressure‐sensitive adhesives (PSAs). To date, the heat resistance of PSAs has not been investigated in sufficient details. In this study, based on the relationship between curing structures and properties, a series of acrylic PSAs with excellent heat resistance were prepared. Commercial zirconium acetylacetonate (ZrACA), desmodur L75 (L75), and N,N,N′,N′‐tetrakis(2,3‐epoxypropyl)‐m‐xylene‐α,α′‐diamine (GA240) were employed as heat‐curing agents. Trimethylolpropane triacrylate (TMPTA) was used as ultraviolet (UV)‐curing agent to form semi‐interpenetration polymer network structures after UV exposure. The influences of different curing agents on the thermal stability, adhesion performance, gel fraction, and viscoelastic of PSAs were explored. The results showed that the PSAs cured by L75, GA240, and TMPTA exhibited excellent heat resistance. Especially, when the content of L75 was 1.0 wt %, the PSAs could be peeled off substrate without residues on substrate surface after treatment at 170 °C for 4 h, while the nonmodified acrylic PSAs possessed residues after treatment from 110 °C. The cured PSAs adhesive performance was evaluated showing maximum 180° peel strength of 16.7 N/25 mm comparable to current PSAs. These resulting PSAs showed high heat resistance and they are suitable for a broad range of special fields. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47310.
Preparation and adsorption mechanism of polyvinyl alcohol/graphene oxide‐sodium alginate nanocomposite hydrogel with high Pb(II) adsorption capacity
Authors: Yu Yaru , Zhang Ge , Ye Lin
Published: November 2018

A series of polyvinyl alcohol (PVA)/graphene oxide (GO)‐sodium alginate (SA) nanocomposite hydrogel beads were prepared through in situ crosslinking for Pb2+ removal. It was found that PVA and SA molecules were intercalated into GO layers through hydrogen bonding interactions, leading to the destruction of orderly structure of GO, while GO uniformly distributed in PVA matrix. With increasing PVA solution concentration, the hydrogel beads became more regular, a large number of polygonal pores with thin walls and open pores formed, the average pore size decreased, and the dense network structure formed. Meanwhile, the permeability of the composite hydrogel decreased, leading to the decline of Pb2+ adsorption capacity of the composite hydrogel. With increasing GO content, the ballability of the hydrogel beads was weakened, the pore size increased, and relatively loose network structure formed, resulting in an increase in permeability and Pb2+ adsorption capacity of the hydrogel, reaching up to 279.43 mg g−1. Moreover, the composite hydrogel presented relatively good reusability for Pb2+ removal. The adsorption mechanism was explored and showed that the adsorption system of the composite hydrogel belonged to the second‐order kinetic model and fitted Langmuir adsorption isotherm model for Pb2+ removal, which might be mono‐layer chemical adsorption. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47318.
Synthesis, characterization, and mechanical performance of various functionalized carbon nanotubes‐polyurethanes nanocomposites
Authors: Antolín‐Cerón Víctor Hugo , Nuño‐Donlucas Sergio Manuel , Barrera‐Rivera Karla Alejandra , Martínez‐Richa Antonio
Published: November 2018

Nanocomposites of functionalized carbon nanotubes (CNTsf) used as a reinforcement agent, and a polyurethane (PU), as a polymeric matrix were synthesized via in situ polymerization. Carbon nanotubes (CNTs) were chemically functionalized using four different chemical treatments to obtain (1) oxidized CNTs (CNTsOH, COOH), (2) CNTs containing aliphatic amine groups (CNTset diam), (3) CNTs attached to an aromatic amine group (CNTs4AB), and (4) CNTs containing a combination of aromatic amine, hydroxyl, and carboxyl functional groups (CNTs4AB, OH, COOH). The nanocomposites (prepared using 0.25, 0.5 or 1.0 wt % CNTsf) were synthesized by two processes: (1) one‐step using a PU made from PCL‐diol (α‐ω‐telechelic polyester diol) obtained by biocatalysis from ε‐caprolactone (ε‐CL) and diethylene glycol (DEG) and 4,4′‐methylenebis (cyclohexyl isocyanate) (H12MDI) in stoichiometric amounts, (2) two‐step process (chain extended PU) using hexamethylene diamine (HMDA). Depending on the chemical route used to synthesized the nanocomposites, CNTsf form, in some cases, covalent bonds and hydrogen bonding with the soft and/or hard segments of the PU matrix. Also, the presence of CNTsf improves the thermal stability of the nanocomposites and some of their mechanical properties, compared to the pure PU properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47319.
Anticorrosive coating based on poly(vinyl acetate) formed by electropolymerization on the copper surface
Authors: Samide Adriana , Brătulescu George , Merişanu Claudia , Cioateră Nicoleta
Published: November 2018

The poly(vinyl acetate) (PVAC) film was obtained by electropolymerization on the copper electrode using cyclic voltammetry performed in mixed electrolyte based on water/ethyl alcohol/acetic acid containing vinyl acetate (VAc) and benzoyl peroxide as polymerization initiator. The coatings were characterized by optical microscopy, scanning electron microscopy (SEM) and infrared (IR) spectroscopy. The corrosion was induced in hydrochloric acid solution using potentiodynamic measurements and electrochemical impedance spectroscopy (EIS). The microscopic and SEM images revealed the PVAC coating formation and IR spectroscopy confirmed that it exhibits the same characteristic bands as a standard PVAC sample. From the potentiodynamic polarization, the PVAC protective performance of 78% was computed. The EIS measurements showed the occurrence of the surface adsorbed layer with a higher impedance response to the frequency and a phase angle maximum shifted to lower values than those of uncoated samples. In addition, the VAc electropolymerization mechanism was discussed and the PVAC adsorption mechanism on the copper surface was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47320.
Role of chain extension in the rheological properties, crystallization behaviors, and microcellular foaming performances of poly (butylene adipate‐co‐terephthalate)
Authors: Song Jingsi , Zhou Hongfu , Wang Xiangdong , Zhang Yuxia , Mi Jianguo
Published: November 2018

Currently, the fabrication of microcellular semicrystalline polymer foam using supercritical CO2as a blowing agent constitutes a worldwide interest. In this work, a facile approach of chain extension and batch foaming was proposed to prepare microcellular semicrystalline poly (butylene adipate‐co‐terephthalate) (PBAT) foam using CO2as a physical blowing agent. With the introduction of chain extender (CE), the weight‐average molecular weight and gel fraction of PBAT samples increased; their crystallization temperature increased from 74.2 to 86.9 °C and their viscoelasticity was improved greatly. Microcellular PBAT foams with the cell size <4 μm and the cell density more than 1010cells cm−3were fabricated successfully. With increasing concentration of CE, the cell density and volume expansion ratio (VER) of various PBAT foams increased from 3.4 × 1010to 8.7 × 1010cells cm−3and from 1.5 to 2.0 times, respectively. With increasing foaming temperature, the cell size and VER increased and the cell density decreased. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47322.
Effect of injection speed on the mechanical properties of isotactic polypropylene micro injection molded parts based on a nanoindentation test
Authors: Wang Lixia , Zhang Yang , Jiang Lin , Yang Xuecheng , Zhou Yiping , Wang Xiaoyu , Li Qian , Shen Changyu , Turng Lih‐Sheng
Published: November 2018

Isotactic polypropylene micro parts were molded at different injection speeds by microinjection molding. The morphology and micro structure were characterized by a polarizing microscope, and the mechanical properties of differently structured layers were characterized by nanoindentation experiments. The influence of injection speed on the nanoindentation mechanical properties of each structural layer of the micro parts was analyzed. The results showed that the mechanical properties of different layers were different, the modulus and hardness of the position near the core layer were largest, and the modulus and hardness of the position near the skin were smallest. It is compelling that the modulus and hardness of each layer decreased first and then increased as the injection speed increased under a higher melt temperature (240 °C). Meanwhile, the opposite trend was observed at a lower melt temperature (220 °C). This phenomenon can be attributed to the competitive mechanism of the shear heat effect and the disorientation effect. In addition, injection speed had a greater influence on the nanoindentation mechanical properties in the perpendicular direction than in the flow direction. This work systematically explored the relationship between the microstructure and the local mechanical properties, which can provide new insights for microinjection molding design in the future. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47329.
Suramin, screened from an approved drug library, inhibits HuR functions and attenuates malignant phenotype of oral cancer cells
Authors: Kakuguchi Wataru , Nomura Takao , Kitamura Tetsuya , Otsuguro Satoko , Matsushita Kazuhiro , Sakaitani Masahiro , Maenaka Katsumi , Tei Kanchu
Published: November 2018

AU‐rich elements (ARE) exist in the 3′‐untranslated regions of the mRNA transcribed from cell growth‐related genes such as proto‐oncogenes, cyclin‐related genes, and growth factors. HuR binds and stabilizes ARE‐mRNA. HuR is expressed abundantly in cancer cells and related malignant phenotypes. HuR knockdown attenuates the malignant phenotype of oral cancer cells. In this study, we screened 1570 compounds in the approved drug library by differential scanning fluorimetry (DSF) to discover a HuR‐targeted compound. Firstly, 55 compounds were selected by DSF. Then, 8 compounds that showed a shift in the melting temperature value in a concentration‐dependent manner were selected by DSF. Of them, suramin, an anti‐trypanosomal drug, binds to HuR, exhibiting fast‐on and fast‐off kinetic behavior on surface plasmon resonance (SPR). We confirmed that suramin significantly decreased mRNA and protein expression of cyclin A2 and cyclin B1. The cyclin A2 and cyclin B1 mRNAs were destabilized by suramin. Furthermore, the motile and invasive activities of a tongue carcinoma cell line treated with suramin were markedly lower than those of control cells. The above findings suggest that suramin binds to HuR and inhibits its function. We also showed that the anticancer effects of suramin were caused by the inhibition of HuR function, indicating its potential as a novel therapeutic agent in the treatment of oral cancer. Our results suggest that suramin, via its different mechanism, may effectively suppress progressive oral cancer that cannot be controlled using other anticancer agents.
Abemaciclib Inhibits Renal Tubular Secretion Without Changing Glomerular Filtration Rate
Authors: Chappell Jill C. , Turner P. Kellie , Pak Y. Anne , Bacon James , Chiang Alan Y. , Royalty Jane , Hall Stephen D. , Kulanthaivel Palaniappan , Bonventre Joseph V.
Published: November 2018

Abemaciclib, an inhibitor of cyclin dependent kinases 4 and 6, is indicated for metastatic breast cancer treatment. Reversible increases in serum creatinine levels of ~15–40% over baseline have been observed following abemaciclib dosing. This study assessed the in vitro and clinical inhibition of renal transporters by abemaciclib and its metabolites using metformin (a clinically relevant transporter substrate), in a clinical study that quantified glomerular filtration and iohexol clearance. In vitro, abemaciclib inhibited metformin uptake by organic cation transporter 2, multidrug and toxin extrusion (MATE)1, and MATE2‐K transporters with a half‐maximal inhibitory concentration of 0.4–3.8 μM. Clinically, abemaciclib significantly increased metformin exposure but did not significantly affect measured glomerular filtration rate, serum neutrophil gelatinase‐associated lipocalin (NGAL), serum cystatin‐C, or the urinary markers of kidney tubular injury, NGAL and kidney injury molecule‐1.
Using magnetic core‐shell nanoparticles coated with an ionic liquid dispersion assisted by effervescence powder for the micro‐solid‐phase extraction of four beta blockers from human plasma by ultra high performance liquid chromatography with mass spectrometry detection
Authors: Jamshidi Sara , Rofouei Mohammad Kazem , Thorsen Gunnar
Published: November 2018

In this work, a novel, efficient, and green sorbent, SiO2@Fe3O4 has been created and functionalized with 1‐butyl‐3‐methylimidazolium hexafluorophosphate as an ionic liquid. This sorbent was applied for microextraction of four beta blockers, propranolol, metoprolol, atenolol, and alprenolol with bupivacaine as internal standard from human plasma followed by liquid chromatography with mass spectrometric detection. A mixture of sodium bicarbonate and sodium dihydrogen phosphate was used as an extractant dispersive agent (effervescent power) to enhance the interaction between the magnetic sorbent and analytes. Main affecting parameters on microextraction and elution were optimized. Figures of merit for dispersive solid phase extraction with ionic liquid coated magnetic nanoparticles assisted by effervescent powder were calculated under the optimized conditions. The detection limits for propranolol, metoprolol, atenolol, and alprenolol were found at 0.33, 0.62, 0.03, and 0.44 ng/mL, respectively. For all analytes, good linearity was obtained. Intra‐ (n = 5) and interday (n = 10) precision were both under 6.3% while the preconcentration factors were obtained in the range between 15–18. The extraction efficiencies for each analyte ranged from 75 to 91%. The method was successfully applied for determination of trace amounts of the beta blockers in human plasma samples.
Establishment of a highly efficient conjugation protocol for Streptomyces kanamyceticus ATCC12853
Authors: Zhang Shuman , Chen Tiansheng , Jia Jia , Guo Liwen , Zhang Huizheng , Li Chao , Qiao Renzhong
Published: November 2018

Kanamycin B as the secondary metabolite of wild‐type Streptomyces kanamyceticus (S. kanamyceticus) ATCC12853 is often used for the synthesis of dibekacin and arbekacin. To construct the strain has the ability for kanamycin B production; the pSET152 derivatives from Escherichia coli ET12567 were introduced to S. kanamyceticus by intergeneric conjugal transfer. In this study, we established a reliable genetic manipulation system for S. kanamyceticus. The key factors of conjugal transfer were evaluated, including donor‐to‐recipient ratio, heat‐shock, and the overlaying time of antibiotics. When spores were used as recipient, the optimal conjugation frequency was up to 6.7 × 10−6. And mycelia were used as an alternative recipient for conjugation instead of spores; the most suitable donor‐to‐recipient ratio is 1:1 (107:107). After incubated for only 10–12 hr and overlaid with antibiotics subsequently, the conjugation frequency can reach to 6.2 × 10−5 which is sufficient for gene knockout and other genetic operation. Based on the optimized conjugal transfer condition, kanJ was knocked out successfully. The kanamycin B yield of kanJ‐disruption strain can reach to 543.18 ± 42 mg/L while the kanamycin B yield of wild‐type strain was only 46.57 ± 12 mg/L. The current work helps improve the content of kanamycin B in the fermentation broth of S. kanamyceticus effectively to ensure the supply for the synthesis of several critical semisynthetic antibiotics.
Cycle‐consistent adversarial denoising network for multiphase coronary CT angiography
Authors: Kang Eunhee , Koo Hyun Jung , Yang Dong Hyun , Seo Joon Bum , Ye Jong Chul
Published: November 2018

Purpose

In multiphase coronary CT angiography (CTA), a series of CT images are taken at different levels of radiation dose during the examination. Although this reduces the total radiation dose, the image quality during the low‐dose phases is significantly degraded. Recently, deep neural network approaches based on supervised learning technique have demonstrated impressive performance improvement over conventional model‐based iterative methods for low‐dose CT. However, matched low‐ and routine‐dose CT image pairs are difficult to obtain in multiphase CT. To address this problem, we aim at developing a new deep learning framework.

Method

We propose an unsupervised learning technique that can remove the noise of the CT images in the low‐dose phases by learning from the CT images in the routine dose phases. Although a supervised learning approach is not applicable due to the differences in the underlying heart structure in two phases, the images are closely related in two phases, so we propose a cycle‐consistent adversarial denoising network to learn the mapping between the low‐ and high‐dose cardiac phases.

Results

Experimental results showed that the proposed method effectively reduces the noise in the low‐dose CT image while preserving detailed texture and edge information. Moreover, thanks to the cyclic consistency and identity loss, the proposed network does not create any artificial features that are not present in the input images. Visual grading and quality evaluation also confirm that the proposed method provides significant improvement in diagnostic quality.

Conclusions

The proposed network can learn the image distributions from the routine‐dose cardiac phases, which is a big advantage over the existing supervised learning networks that need exactly matched low‐ and routine‐dose CT images. Considering the effectiveness and practicability of the proposed method, we believe that the proposed can be applied for many other CT acquisition protocols.
A Novel Technique to Assess Distal Radioulnar Joint Stability Using Increasing Torque
Authors: Nilsson Klara , Hallberg Peter , Tesselaar Erik , Farnebo Simon
Published: November 2018

Background Previous studies on computed tomography (CT) in patients with a suspected triangular fibrocartilage complex (TFCC) injury have not been successful in assessing distal radioulnar joint (DRUJ) laxity. The aim of this study was to develop a novel servomotor-driven device for the assessment of DRUJ by applying increasing torque to the DRUJ in pronation and supination.

Methods A custom-built device was designed to function during four-dimensional (4D) CT of the wrist. A torque meter, positioned between the incoming hand holder, and a direct current (DC) servomotor were used for angular positioning and for applying rotational force to the patient's arm. A total of 110 healthy participants were recruited to gather reference values for the range of motion (ROM), maximum torque in neutral and supinated/pronated position, and the ability to withstand an increasing, device-generated torque in these positions. The device was also used during 4D DRUJ CT in five patients with suspected TFCC injuries.

Results A gender- and age-relevant reference chart for ROM and torque was created. Men showed a tendency (ns) toward having a larger ROM and increasing strength with increasing age, whereas women showed the opposite. Also, the dominant hand showed a tendency toward having a larger ROM and being stronger than the nondominant hand (ns). A smaller cohort of patients (n = 5) with suspected TFCC injuries showed a significantly decreased ability to withstand increasing torque in both supination (2.1 ± 0.3 vs. 3.1 ± 0.2 s; p < 0.005) and pronation (2.3 ± 0.5 vs. 3.1 ± 0.4 s; p < 0.0005) and also showed a clear laxity on real-time 4D CT image sequences. Decreased strength at all positions was also found (average 74% decrease compared to noninjured side).

Conclusion Reference values for torque strength and ability to withstand increasing torque can be used clinically in the assessment of patients with symptoms that could represent ligamentous injuries to the TFCC. The ability to use the device during CT enables radiographic evaluation of instability during increasing torque.

Level of Evidence This is a Level II study.
Diagnostic Imaging and Management of Common Intra-articular and Peri-articular Soft Tissue Tumors and Tumorlike Conditions of the Knee
Authors: Evenski Andrea , Stensby James , Rosas Samuel , Emory Cynthia
Published: November 2018

Intra-articular (IA) and peri-articular (PA) tumors of the knee are frequently encountered by orthopaedic surgeons. Nonetheless, due to the possibility of great morbidity and potential mortality, it is important to recognize and differentiate between benign and malignant lesions in a timely manner. Therefore, the purpose of this article is to provide a concise, practical, and updated review of commonly encountered IA and PA tumors including intratendinous gout, synovial chondromatosis, schwannoma, pigmented villonodular synovitis, and synovial sarcoma, and a detailed description of differentiating features to include various imaging modalities.
Report of Another Mutation Proven Case of Carbonic Anhydrase II Deficiency
Authors: Satapathy Amit , Pandey Swati , Chaudhary Madhumita , Bagga Arvind , Kabra Madhulika , Uwe Kornak , Gupta Neerja
Published: November 2018

Carbonic anhydrase (CA) II deficiency results in an uncommon type of autosomal recessive sclerosing bone dysplasia with renal tubular acidosis and intracerebral calcification. We report a classic case of CA II-associated osteopetrosis with a previously reported homozygous frameshift mutation. Child was evaluated for short stature and failure to thrive. He was diagnosed as osteopetrosis in view of the presence of hepatosplenomegaly and increased bone density though hematological parameters were normal. Further evaluation showed presence of associated distal renal tubular acidosis raising a possibility of CA II deficiency. Mutation analysis revealed a previously reported homozygous frameshift mutation c.143-146delCTGT (p.Ser48Phefs*9) in CA2.Child has normal growth after initiation of alkali therapy.
Demographics and Clinical Outcomes of Patients Undergoing Anterior Cruciate Ligament Reconstruction with a Planned or Unplanned Hybrid Graft
Authors: Kraeutler Matthew J. , Houck Darby A. , Carver Trevor J. , Bravman Jonathan T. , Vidal Armando F. , McCarty Eric C.
Published: November 2018

The purpose of this study was to report the demographics and clinical outcomes of patients at our institution following anterior cruciate ligament reconstruction (ACLR) with a planned or unplanned hybrid autograft–allograft. At a minimum 2-year follow-up, patients at our institution who had undergone primary ACLR with a planned (P) or unplanned (U) hybrid graft using fresh-frozen allografts were contacted to complete a survey containing the Knee Injury and Osteoarthritis Outcome Score, Subjective International Knee Documentation Committee score, Single Assessment Numeric Evaluation, 12-Item Short Form Health Survey, and visual analog scale for activity level. Demographics were compared between groups. Patient-reported outcomes (PROs) and a revision rate were reported for each group. Mean follow-up among all patients was 3.3 years. Revision rate at follow-up was 0.8 and 6.3% in the P and U groups, respectively (p = 0.03). Among patients reached for follow-up (90 P, 30 U), a lower proportion of males was found in the unplanned hybrid graft group (P: 52%, U: 23%, p < 0.01). Unplanned hybrid graft patients were significantly younger at the time of surgery (P: 41.0 years, U: 31.0 years, p < 0.0001). Graft size did not differ between groups (P: 9.1 mm, U: 8.9 mm, p = 0.11). Patients in both groups achieved moderate to high PROs. Demographics differ between patients undergoing ACLR with a planned or unplanned hybrid graft. Patients with a planned hybrid graft are at a significantly reduced risk of postoperative graft failure, likely due to the older age of this group.
Evaluation and Treatment of Alkalosis in Children
Authors: Kopač Matjaž
Published: November 2018

Alkalosis is a disorder of acid–base balance defined by elevated pH of the arterial blood. Metabolic alkalosis is characterized by primary elevation of the serum bicarbonate. Due to several mechanisms, it is often associated with hypochloremia and hypokalemia and can only persist in the presence of factors causing and maintaining alkalosis. Respiratory alkalosis is a consequence of dysfunction of respiratory system's control center. There are no pathognomonic symptoms. History is important in the evaluation of alkalosis and usually reveals the cause. It is important to evaluate volemia during physical examination. Treatment must be causal and prognosis depends on a cause.
A NuSTAR study of the 55 ks hard X-ray pulse-phase modulation in the magnetar 4U 0142+61
Authors: Makishima Kazuo , Murakami Hiroaki , Enoto Teruaki , Nakazawa Kazuhiro
Published: November 2018

Archival NuSTAR data of the magnetar 4U 0142+61, acquired in 2014 March for a total time span of 258 ks, were analyzed. This is to reconfirm the 55 ks modulation in the hard X-ray pulse phases of this source, found with a Suzaku observation in 2009 (Makishima et al., 2014, Phys. Rev. Lett., 112, 171102). Indeed, the 10–70 keV X-ray pulsation, detected with NuSTAR at 8.68917 s, was found to be also phase-modulated (at >98% confidence) at the same ∼55 ks period, or half that value. Furthermore, a brief analysis of another Suzaku data set of 4U 0142+61, acquired in 2013, reconfirmed the same 55 ks phase modulation in the 15–40 keV pulses. Thus, the hard X-ray pulse-phase modulation was detected with Suzaku (in 2009 and 2013) and NuSTAR (in 2014) at a consistent period. However, the modulation amplitude varied significantly; A ∼ 0.7 s with Suzaku (in 2009), A ∼ 1.2 s with Suzaku (in 2013), and A ∼ 0.17 s with NuSTAR. In addition, the phase modulation properties detected with NuSTAR differed considerably between the first 1/3 and the latter 2/3 of the observation. In energies below 10 keV, the pulse-phase modulation was not detected with either Suzaku or NuSTAR. These results reinforce the view of Makishima et al. (2014, Phys. Rev. Lett., 112, 171102); the neutron star in 4U 0142+61 keeps free precession, under a slight axial deformation due probably to ultra-high toroidal magnetic fields of ∼1016 G. The wobbling angle of precession should remain constant, but the pulse-phase modulation amplitude varies on time scales of months to years, presumably as asymmetry of the hard X-ray emission pattern around the star’s axis changes.
Convolutional models of RNA energetics
Authors: Wu Michelle J.
Published: November 2018

Nucleic acid molecular biology and synthetic biology are undergoing rapid advances with the emergence of designer riboswitches controlling living cells, CRISPR/Cas9-based genome editing, high-throughput RNA-based silencing, and reengineering of mRNA translation. Many of these efforts require the design of nucleic acid interactions, which relies on accurate models for DNA and RNA energetics. Existing models utilize nearest neighbor rules, which were parameterized through careful optical melting measurements. However, these relatively simple rules often fail to quantitatively account for the biophysical behavior of molecules even in vitro, let alone in vivo. This is due to the limited experimental throughput of optical melting experiments and the infinitely large space of possible motifs that can be formed. Here, we present a convolutional neural network architecture to model the energies of nucleic acid motifs, allowing for learning of representations of physical interactions that generalize to arbitrary unmeasured motifs. First, we used existing parameterizations of motif energies to train the model and demonstrate that our model is expressive enough to recapitulate the current model. Then, through training on optical melting datasets from the literature, we have shown that the model can accurately predict the thermodynamics of hairpins containing unmeasured motifs. This work demonstrates the utility of convolutional models for capturing the thermodynamic parameters that underlie nucleic acid interactions.
MCS2: Minimal coordinated supports for fast enumeration of minimal cut sets in metabolic networks
Authors: Miraskarshahi Reza , Zabeti Hooman , Stephen Tamon , Chindelevitch Leonid
Published: November 2018

Motivation

Constraint-based modeling of metabolic networks helps researchers gain insight into the metabolic processes of many organisms, both prokaryotic and eukaryotic. Minimal Cut Sets (MCSs) are minimal sets of reactions whose inhibition blocks a target reaction in a metabolic network. Most approaches for finding the MCSs in constrained-based models require, either as an intermediate step or as a byproduct of the calculation, the computation of the set of elementary flux modes (EFMs), a convex basis for the valid flux vectors in the network. Recently, Ballerstein et al. [BvKKH11] proposed a method for computing the MCSs of a network without first computing its EFMs, by creating a dual network whose EFMs are a superset of the MCSs of the original network. However, their dual network is always larger than the original network and depends on the target reaction.

Here we propose the construction of a different dual network, which is typically smaller than the original network and is independent of the target reaction, for the same purpose. We prove the correctness of our approach, MCS2, and describe how it can be modified to compute the few smallest MCSs for a given target reaction.

Results

We compare MCS2 to the method of Ballerstein et al. and two other existing methods. We show that MCS2 succeeds in calculating the full set of MCSs in many models where other approaches cannot finish within a reasonable amount of time. Thus, in addition to its theoretical novelty, our approach provides a practical advantage over existing methods.

Availability

MCS2 is freely available at https://github.com/RezaMash/MCS under the GNU 3.0 license.
A Novel Melatonergic Signature Predicts Reccurence Risk and Therapeutic Response in Breast Cancer Patients
Authors: Tran Hoa Quynh , Luu Phuc Loi , Than Van Thai , Clarke Declan , Lam Hanh Ngoc , Nguyen Dinh Truong , Thi Le Kim Van , Nguyen Trung Viet , Le Minh Thong , Hoang Xuan The , Duy Phan Q. , Tran Huyen , Nguyen Minh Nam
Published: November 2018

ASMT is a key determinant of the levels of released melatonin. Though melatonin has been shown to exhibit anti-cancer activity and prevents endocrine resistance in breast cancer, the role of ASMT in breast cancer progression remains unclear. In this retrospective study, we analyzed gene expression profiles from thousands of patients and found thatASMTexpression was significantly lower in breast cancer tumors relative to healthy tissue. Among cancer patients, those with greater expression had better relapse-free survival outcomes and longer metastasis-free survival times, and they also experienced longer periods before relapse or distance recurrence following tamoxifen treatment. Administration of melatonin, in combination with tamoxifen, further promoted cancer cell death by promoting apoptosis. Motivated by these results, we devised an ASMT gene signature that identifies low-risk cases with great accuracy. This signature was validated using both mRNA array and RNAseq datasets. Intriguingly, patients who are classified as high-risk benefit from adjuvant chemotherapy, and those with grade II tumors who are classified as low-risk exhibit improved overall survival and distance relapse-free outcomes following endocrine therapy. Our findings more clearly elucidate the roles ofASMT,provide strategies for improving the efficacy of tamoxifen treatment, and help to identify those patients who may maximally benefit from adjuvant or endocrine therapies.