bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-Structural Proteins from Human T-cell Leukemia Virus Type 1 in Cellular Membranes—Mechanisms for Viral Survivability and Proliferation
Authors: Georgieva Elka R.
Published: November 2018

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of illnesses, such as adult T-cell leukemia/lymphoma, myelopathy/tropical spastic paraparesis (a neurodegenerative disorder), and other diseases. Therefore, HTLV-1 infection is a serious public health concern. Currently, diseases caused by HTLV-1 cannot be prevented or cured. Hence, there is a pressing need to comprehensively understand the mechanisms of HTLV-1 infection and intervention in host cell physiology. HTLV-1-encoded non-structural proteins that reside and function in the cellular membranes are of particular interest, because they alter cellular components, signaling pathways, and transcriptional mechanisms. Summarized herein is the current knowledge about the functions of the membrane-associated p8I, p12I, and p13II regulatory non-structural proteins. p12I resides in endomembranes and interacts with host proteins on the pathways of signal transduction, thus preventing immune responses to the virus. p8I is a proteolytic product of p12I residing in the plasma membrane, where it contributes to T-cell deactivation and participates in cellular conduits, enhancing virus transmission. p13II associates with the inner mitochondrial membrane, where it is proposed to function as a potassium channel. Potassium influx through p13II in the matrix causes membrane depolarization and triggers processes that lead to either T-cell activation or cell death through apoptosis.
Genomic and Transcriptomic Analysis of Hypercholesterolemic Rabbits: Progress and Perspectives
Authors: Fan Jianglin , Chen Yajie , Yan Haizhao , Liu Baoning , Wang Yanli , Zhang Jifeng , Chen Y. , Liu Enqi , Liang Jingyan
Published: November 2018

Rabbits (Oryctolagus cuniculus) are one of the most widely used animal models for the study of human lipid metabolism and atherosclerosis because they are more sensitive to a cholesterol diet than other experimental animals such as rodents. Currently, two hypercholesterolemic rabbit models are frequently used for atherosclerosis studies. One is a cholesterol-fed wild-type rabbit and the other is the Watanabe heritable hyperlipidemic (WHHL) rabbit, which is genetically deficient in low density lipoprotein (LDL) receptor function. Wild-type rabbits can be easily induced to develop severe hypercholesterolemia with a cholesterol-rich diet due to the marked increase in hepatically and intestinally derived remnant lipoproteins, called β-very low density lipoproteins (VLDL), which are rich in cholesteryl esters. WHHL rabbits are characterized by elevated plasma LDL levels on a standard chow diet, which resembles human familial hypercholesterolemia. Therefore, both rabbit models develop aortic and coronary atherosclerosis, but the elevated plasma cholesterol levels are caused by completely different mechanisms. In addition, cholesterol-fed rabbits but not WHHL rabbits exhibit different degrees of hepatosteatosis. Recently, we along with others have shown that there are many differentially expressed genes in the atherosclerotic lesions and livers of cholesterol-fed rabbits that are either significantly up- or down-regulated, compared with those in normal rabbits, including genes involved in the regulation of inflammation and lipid metabolism. Therefore, dietary cholesterol plays an important role not only in hypercholesterolemia and atherosclerosis but also in hepatosteatosis. In this review, we make an overview of the recent progress in genomic and transcriptomic analyses of hypercholesterolemic rabbits. These transcriptomic profiling data should provide novel insight into the relationship between hypercholesterolemia and atherosclerosis or hepatic dysfunction caused by dietary cholesterol.
Hypoxic Microenvironment and Metastatic Bone Disease
Authors: Hiraga Toru
Published: November 2018

Hypoxia is a common feature of solid tumors and is associated with an increased risk of metastasis and a poor prognosis. Recent imaging techniques revealed that bone marrow contains a quite hypoxic microenvironment. Low oxygen levels activate hypoxia signaling pathways such as hypoxia-inducible factors, which play critical roles in the key stages of metastatic dissemination including angiogenesis, epithelial-mesenchymal transition, invasion, maintenance of cancer stem cells, tumor cell dormancy, release of extracellular vesicles, and generation of pre-metastatic niches. Hypoxia also affects bone cells, such as osteoblasts and osteoclasts, and immune cells, which also act to support the development and progression of bone metastases. Paradoxically, hypoxia and related signaling molecules are recognized as high-priority therapeutic targets and many candidate drugs are currently under preclinical and clinical investigation. The present review focuses on our current knowledge of the potential roles of hypoxia in cancer metastasis to bone by considering the interaction between metastatic cancer cells and the bone microenvironment. Current therapeutic approaches targeting hypoxia are also described.
Comparative Transcriptome Analysis Provides Novel Insight into Morphologic and Metabolic Changes in the Fat Body during Silkworm Metamorphosis
Authors: Peng Jian , Li Zheng , Yang Yan , Wang Peng , Zhou Xuan , Zhao Tujing , Guo Mengpei , Meng Meng , Zhang Tianlei , Qian Wenliang , Xia Qingyou , Cheng Daojun , Zhao Ping
Published: November 2018

The fat body plays key roles in energy storage and utilization as well as biosynthetic and metabolic activities in insects. During metamorphosis from larva to pupa, the fat body undergoes dramatic changes in morphology and metabolic processes. However, the genetic basis underlying these changes has not been completely understood. In this study, the authors performed a time-course transcriptome analysis of the fat body during silkworm metamorphosis using RNA-sequencing. A total of 5217 differentially expressed genes (DEGs) were identified in the fat body at different developmental time points. DEGs involved in lipid synthesis and degradation were highly expressed at the third day of the last larval instar and during the prepupal-pupal transition, respectively. DEGs involved in the ecdysone signaling and bone morphogenetic protein (BMP) signaling pathways that modulate organ development exhibited a high expression level during the fat body remodeling process from prepupa to pupa. Intriguingly, the RNA interference-mediated knockdown of either decapentaplegic (Dpp) or protein 60A (Gbb), two DEGs involved in the BMP signaling pathway, inhibited fat body dissociation but promoted lipid mobilization, suggesting that the BMP signaling pathway not only is required for fat body remodeling, but also moderately inhibits lipid mobilization to ensure an appropriate lipid supply during the pupal-adult transition. In conclusion, the comparative transcriptome analysis provides novel insight into morphologic and metabolic changes in the fat body during silkworm metamorphosis.
Effects of the Environmental Temperature on Aedes aegypti and Aedes albopictus Mosquitoes: A Review
Authors: Reinhold Joanna , Lazzari Claudio , Lahondère Chloé
Published: November 2018

The temperature of the environment is one of the most important abiotic factors affecting the life of insects. As poikilotherms, their body temperature is not constant, and they rely on various strategies to minimize the risk of thermal stress. They have been thus able to colonize a large spectrum of habitats. Mosquitoes, such as Ae. aegypti and Ae. albopictus, vector many pathogens, including dengue, chikungunya, and Zika viruses. The spread of these diseases has become a major global health concern, and it is predicted that climate change will affect the mosquitoes’ distribution, which will allow these insects to bring new pathogens to naïve populations. We synthesize here the current knowledge on the impact of temperature on the mosquito flight activity and host-seeking behavior (1); ecology and dispersion (2); as well as its potential effect on the pathogens themselves and how climate can affect the transmission of some of these pathogens (3).
Unique MicroRNA and mRNA Interactions in EGFR-Mutated Lung Adenocarcinoma
Authors: Subat Sophia , Inamura Kentaro , Ninomiya Hironori , Nagano Hiroko , Okumura Sakae , Ishikawa Yuichi
Published: November 2018

The EGFR gene was one of the first molecules to be selected for targeted gene therapy. EGFR-mutated lung adenocarcinoma, which is responsive to EGFR inhibitors, is characterized by a distinct oncogenic pathway in which unique microRNA (miRNA)–mRNA interactions have been observed. However, little information is available about the miRNA–mRNA regulatory network involved. Both miRNA and mRNA expression profiles were investigated using microarrays in 155 surgically resected specimens of lung adenocarcinoma with a known EGFR mutation status (52 mutated and 103 wild-type cases). An integrative analysis of the data was performed to identify the unique miRNA–mRNA regulatory network in EGFR-mutated lung adenocarcinoma. Expression profiling of miRNAs and mRNAs yielded characteristic miRNA/mRNA signatures (19 miRNAs/431 mRNAs) in EGFR-mutated lung adenocarcinoma. Five of the 19 miRNAs were previously listed as EGFR-mutation-specific miRNAs (i.e., miR-532-3p, miR-500a-3p, miR-224-5p, miR-502-3p, and miR-532-5p). An integrative analysis of miRNA and mRNA expression revealed a refined list of putative miRNA–mRNA interactions, of which 63 were potentially involved in EGFR-mutated tumors. Network structural analysis provided a comprehensive view of the complex miRNA–mRNA interactions in EGFR-mutated lung adenocarcinoma, including DUSP4 and MUC4 axes. Overall, this observational study provides insight into the unique miRNA–mRNA regulatory network present in EGFR-mutated tumors. Our findings, if validated, would inform future research examining the interplay of miRNAs and mRNAs in EGFR-mutated lung adenocarcinoma.
A DNA Methylation-Based Test for Breast Cancer Detection in Circulating Cell-Free DNA
Authors: Salta Sofia , P. Nunes Sandra , Fontes-Sousa Mário , Lopes Paula , Freitas Micaela , Caldas Margarida , Antunes Luís , Castro Fernando , Antunes Pedro , Palma de Sousa Susana , Henrique Rui , Jerónimo Carmen
Published: November 2018

Background: Breast cancer (BrC) is the most frequent neoplasm in women. New biomarkers, including aberrant DNA methylation, may improve BrC management. Herein, we evaluated the detection and prognostic performance of seven genes’ promoter methylation (APC, BRCA1, CCND2, FOXA1, PSAT1, RASSF1A and SCGB3A1). Methods: Methylation levels were assessed in primary BrC tissues by quantitative methylation-specific polymerase chain reaction (QMSP) and in circulating cell-free DNA (ccfDNA) by multiplex QMSP from two independent cohorts of patients (Cohort #1, n = 137; and Cohort #2, n = 44). Receiver operating characteristic (ROC) curves were constructed, and log-rank test and Cox regression were performed to assess the prognostic value of genes’ methylation levels. Results: The gene-panel APC, FOXA1, RASSF1A, SCGB3A1 discriminated normal from cancerous tissue with high accuracy (95.55%). In multivariable analysis, high PSAT1-methylation levels [>percentile 75 (P75)] associated with longer disease-free survival, whereas higher FOXA1-methylation levels (>P75) associated with shorter disease-specific survival. The best performing panel in ccfDNA (APC, FOXA1 and RASSF1A) disclosed a sensitivity, specificity and accuracy over 70%. Conclusions: This approach enables BrC accurate diagnosis and prognostic stratification in tissue samples, and allows for early detection in liquid biopsies, thus suggesting a putative value for patient management.
A Systems Dynamics Enabled Real-Time Efficiency for Fuel Cell Data-Driven Remanufacturing
Authors: Okorie Okechukwu , Salonitis Konstantinos , Charnley Fiona , Turner Christopher
Published: November 2018

Remanufacturing is a viable option to extend the useful life of an end-of-use product or its parts, ensuring sustainable competitive advantages under the current global economic climate. Challenges typical to remanufacturing still persist, despite its many benefits. According to the European Remanufacturing Network, a key challenge is the lack of accurate, timely and consistent product knowledge as highlighted in a 2015 survey of 188 European remanufacturers. With more data being produced by electric and hybrid vehicles, this adds to the information complexity challenge already experienced in remanufacturing. Therefore, it is difficult to implement real-time and accurate remanufacturing for the shop floor; there are no papers that focus on this within an electric and hybrid vehicle environment. To address this problem, this paper attempts to: (1) identify the required parameters/variables needed for fuel cell remanufacturing by means of interviews; (2) rank the variables by Pareto analysis; (3) develop a casual loop diagram for the identified parameters/variables to visualise their impact on remanufacturing; and (4) model a simple stock and flow diagram to simulate and understand data and information-driven schemes in remanufacturing.
Characterization and Analysis of Strain Heterogeneity at Grain-Scale of Titanium Alloy with Tri-Modal Microstructure during Tensile Deformation
Authors: Gao Pengfei , Li Yanxi , Wu Ronghai , Lei Zhenni , Cai Yang , Zhan Mei
Published: November 2018

Grain-scale strain heterogeneity characteristics play a critical role in the ductile damage behavior and mechanical properties of two-phase titanium alloys. In this work, the grain-scale strain distribution, strain heterogeneity, and strain localization of titanium alloy with tri-modal microstructure (consisting of equiaxed α (αp), lamellar α (αl), and β transformed matrix (βt)) during tensile deformation were experimentally investigated. The results show that the strain probability distribution of the whole microstructure obeys normal distribution during deformation. Significant strain heterogeneities exist in each constituent (αp, αl, and βt) and the whole microstructure. At lower macro-strain, αp and αl exhibit higher average strain than those of βt and the whole of the microstructure. Meanwhile, strain heterogeneity of each constituent is small and has a negligible change. The strain heterogeneity of the whole microstructure is mainly determined by αp. At larger macro-strain, some highly deformed regions produce and their positions do not change during further deformation. As a result, the strain heterogeneity of each constituent increases fast, and the strain heterogeneity of whole microstructure is mainly related to αl in this deformation stage. On the other hand, two types of strain localization may be generated within αp and αl and at the αp/βt and αl/βt boundaries, respectively. The former type is caused by transgranular intense slip deformation and presents crystal orientation dependence. The latter type is related to the boundary sliding and presents spatial distribution dependence for αl. These strain localizations greatly determine the micro-damages, thus forming the corresponding micro-voids within αp and αl and the micro-cracks at αp/βt and αl/βt boundaries in tri-modal microstructure at larger deformation.
Thermodynamic Study of the Corrosion of Refractories by Sodium Carbonate
Authors: Zhao Ying , Cheng Guishi , Xiang Yu , Long Fei , Dong Changqing
Published: November 2018

The corrosion of refractories by sodium salts in waste liquid at high temperature has become a serious problem. This paper focuses on the thermodynamic characterization of sodium carbonate (Na2CO3) corrosion of six refractories by FactSage modelling in combination with X-ray diffraction (XRD). Three of the refractories are oxides (Fe2O3, Al2O3, and Cr2O3), and the other three are synthetics spinels (magnesium chromium, MgO·Cr2O3; magnesioferrite, MgO·Fe2O3; and, magnesium aluminium, MgO·Al2O3). First, thermodynamic simulations were carried out with the FactSage thermodynamics model using the reaction package to predict the direction of the Na2CO3 corrosion reaction in terms of the Gibbs free energy. Then, the reactions between the six refractories and Na2CO3 were conducted through a series of refractories/Na2CO3 reaction tests. The XRD analytical method was used to describe and understand the chemistry and interpret mineral matter transformation. The products of the tests were also determined by X-ray diffraction and the experimental observations were compared with the results of the thermodynamic simulations. Furthermore, the strength of sodium corrosion of the refractory materials was comprehensively discussed. The results show that MgO·Al2O3 has the best thermal stability and it is hard to corrode by Na2CO3, while the chrome-containing refractory reacts easily with Na2CO3 with a considerably high amount of corrosion product at a temperature of 600 °C. These experimental results are in agreement with the thermodynamic calculations.
Effects of F-Doping on the Electrochemical Performance of Na2Ti3O7 as an Anode for Sodium-Ion Batteries
Authors: Chen Zehua , Lu Liang , Gao Yu , Zhang Qixiang , Zhang Chuanxiang , Sun Chunwen , Chen Xingying
Published: November 2018

The effects of fluorine (F) doping on the phase, crystal structure, and electrochemical performance of Na2Ti3O7 are studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical measurements. F-doping does not change the crystal structure of NTO, although it has an effect on the morphology of the resultant product. As an anode material for sodium-ion batteries, the specific capacity of Na2Ti3O7 exhibits a 30% increase with F-doping owing to the improved sodium ion diffusion coefficient. F-doped Na2Ti3O7 also displays an enhanced rate capability and favourable cycling performance for more than 800 cycles.
Valorization of Tomato Processing by-Products: Fatty Acid Extraction and Production of Bio-Based Materials
Authors: Benítez José J. , Castillo Paula M. , Del Río José C. , León-Camacho Manuel , Domínguez Eva , Heredia Antonio , Guzmán-Puyol Susana , Athanassiou Athanassia , Heredia-Guerrero José A.
Published: November 2018

A method consisting of the alkaline hydrolysis of tomato pomace by-products has been optimized to obtain a mixture of unsaturated and polyhydroxylated fatty acids as well as a non-hydrolysable secondary residue. Reaction rates and the activation energy of the hydrolysis were calculated to reduce costs associated with chemicals and energy consumption. Lipid and non-hydrolysable fractions were chemically (infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC-MS)) and thermally (differential scanning calorimetry (DSC), thermogravimetric analysis (TGA)) characterized. In addition, the fatty acid mixture was used to produce cutin-based polyesters. Freestanding films were prepared by non-catalyzed melt-polycondensation and characterized by Attenuated Total Reflected-Fourier Transform Infrared (ATR-FTIR) spectroscopy, solid-state nuclear magnetic resonance (NMR), DSC, TGA, Water Contact Angles (WCA), and tensile tests. These bio-based polymers were hydrophobic, insoluble, infusible, and thermally stable, their physical properties being tunable by controlling the presence of unsaturated fatty acids and oxygen in the reaction. The participation of an oxidative crosslinking side reaction is proposed to be responsible for such modifications.
Properties of Functions Involving Struve Function
Authors: Mosiun Jonathan Aaron Azlan , Halim Suzeini Abdul
Published: November 2018

Let f ( z ) = z + ∑ n = 2 ∞ a n z n and g p , b , c ( z ) = z + ∑ n = 2 ∞ ( − c 4 ) n − 1 ( 3 2 ) n − 1 ( k ) n − 1 z n with p , b , c ∈ ℂ , k = p + b + 2 2 ≠ 0 , − 1 , − 2 , … be two analytic functions in the unit disk U = { z : | z | < 1 } . This paper gives conditions so that the function T p , b , c ( z ) = ( f ∗ g ) ( z ) , a function associated with the Struve function, is univalent, starlike, or convex in the unit disk.
Preparation of Polymer Electrolyte Membranes via Radiation-Induced Graft Copolymerization on Poly(ethylene-alt-tetrafluoroethylene) (ETFE) Using the Crosslinker N,N′-Methylenebis(acrylamide)
Authors: Ke Xi , Drache Marco , Gohs Uwe , Kunz Ulrich , Beuermann Sabine
Published: November 2018

Polymer electrolyte membranes (PEM) prepared by radiation-induced graft copolymerization are investigated. For this purpose, commercial poly(ethylene-alt-tetrafluoroethylene) (ETFE) films were activated by electron beam treatment and subsequently grafted with the monomers glycidyl methacrylate (GMA), hydroxyethyl methacrylate (HEMA) and N,N′-methylenebis(acrylamide) (MBAA) as crosslinker. The target is to achieve a high degree of grafting (DG) and high proton conductivity. To evaluate the electrochemical performance, the PEMs were tested in a fuel cell and in a vanadium redox-flow battery (VRFB). High power densities of 134 mW∙cm−2 and 474 mW∙cm−2 were observed, respectively.
Study on the Effect of Energy-Input on the Joint Mechanical Properties of Rotary Friction-Welding
Authors: Wang Guilong , Li Jinglong , Wang Weilong , Xiong Jiangtao , Zhang Fusheng
Published: November 2018

The objective of the present study is to investigate the effect of energy-input on the mechanical properties of a 304 stainless-steel joint welded by continuous-drive rotary friction-welding (RFW). RFW experiments were conducted over a wide range of welding parameters (welding pressure: 25–200 MPa, rotation speed: 500–2300 rpm, welding time: 4–20 s, and forging pressure: 100–200 MPa). The results show that the energy-input has a significant effect on the tensile strength of RFW joints. With the increase of energy-input, the tensile strength rapidly increases until reaching the maximum value and then slightly decreases. An empirical model for energy-input was established based on RFW experiments that cover a wide range of welding parameters. The accuracy of the model was verified by extra RFW experiments. In addition, the model for optimal energy-input of different forging pressures was obtained. To verify the accuracy of the model, the optimal energy-input of a 170 MPa forging pressure was calculated. Three RFW experiments in which energy-input was equal to the calculated value were made. The joints’ tensile strength coefficients were 90%, 93%, and 96% respectively, which proved that the model is accurate.
Experimental Investigation of Phase Equilibria in the Co-Re-Ta Ternary System
Authors: Liu Xingjun , Wu Dan , Zhang Jinbin , Yang Mujin , Zhu Jiahua , Li Lingling , Chen Yuechao , Yang Shuiyuan , Han Jiajia , Lu Yong , Wang Cuiping
Published: November 2018

In this study, the isothermal sections of the Co-Re-Ta ternary system at 1100, 1200, and 1300 °C have been experimentally investigated by means of electron probe microanalysis and X-ray diffraction. The results indicated the following: (1) The solid solubilities of the λ3, (εCo, Re), χ-Re7Ta3, and bcc-(Ta) phases were large and changed very little from 1100 to 1300 °C; (2) more interestingly, the λ2 phase, with a very limited solubility of Re, was surrounded by the λ3 phase; (3) the solubility of Re for the μ-Co6Ta7 phase increased slowly from 1100 to 1300 °C. These experimental results will be useful for Co-based high-temperature alloys, especially as a supplement for thermodynamic databases.
Efficiency of Sulfuric Acid on Selective Scandium Leachability from Bauxite Residue
Authors: Ochsenkuehn-Petropoulou Maria , Tsakanika Lamprini-Areti , Lymperopoulou Theopisti , Ochsenkuehn Klaus-Michael , Hatzilyberis Konstantinos , Georgiou Paraskevas , Stergiopoulos Chrysanthos , Serifi Olga , Tsopelas Fotis
Published: November 2018

Bauxite residue (BR) is a well promising resource for critical metals, especially scandium (Sc), a rare and expensive metal with increasing applications in advanced technology. Greek BR seems to significantly favor a commercially viable recovery of Sc combining optimized leaching and advanced separation techniques. Leaching with mineral acids emerges as the dominant selection compared to other techniques. This study investigates an optimized leaching condition set for Sc recovery, using the most advantageous option of sulfuric acid. The main target is to develop a leaching scale-up process to be established in the premises of Mytilineos S.A. (formerly Aluminium of Greece, the largest Greek alumina and aluminum producer), taking into account the feed requirements of a subsequent advanced ion exchanged procedure. Several parameters were studied individually or combined in order to achieve high Sc concentration in the leachate and to ensure selectivity, especially concerning iron. The most significant parameters prove to be the solid-to-liquid ratio (S/L), the final pH value, and the leachate’s recycling. The proposed process, with low molarities of sulfuric acid and ambient conditions, integrates rapidly, leading to high and selective Sc recovery. Finally, a leaching process flow diagram under continuous operation on an industrial scale is developed.
Uniaxial Low-Cycle Fatigue Study of Alloy 800H Weldments at 700 °C
Authors: Dewa Rando Tungga , Kim Seon-Jin , Kim Woo-Gon , Kim Eung-Seon
Published: November 2018

Alloy 800H is currently under consideration to be used in a very high temperature reactor system. This paper describes the experimental low-cycle fatigue study on Alloy 800H base metal and weldments in the air with fully-reversed strain control at 700 °C. The recommended modern Alloy 800H weldments were fabricated by gas tungsten arc welding. The observed fatigue life is found to be comparable between base metal and weldments at this temperature, indicating the welding technique can compete with base material. The influence of hold time was further investigated at the maximum tensile strain of 0.6% total strain range condition for 60 s, and it is found to reduce the fatigue life. For most of the tests, the base metal revealed an initial cyclic hardening stress response, otherwise, the weldment was entirely softened with cycles. The addition of hold time is also found to induce an unequal cyclic stress response in both materials. Accordingly, for continuous low-cycle fatigue tests, fatigue cracks were initiated and propagated in a classical transgranular fracture mode. However, the hold time affected the mixed-mode fracture mode by means of a transition from transgranular to intergranular fracture.
Copper Isotope Constraints on the Genesis of the Keweenaw Peninsula Native Copper District, Michigan, USA: A Comment
Authors: Brown Alex C.
Published: November 2018

Well-grouped δ65Cu values (−0.3 to +0.8‰)  from120 samples of native copper fromthe Keweenaw native copper district have been attributed [...]
Optimization of the Synthesis of Glycerol Derived Monoethers from Glycidol by Means of Heterogeneous Acid Catalysis
Authors: Pires Elisabet , García José Ignacio , Leal-Duaso Alejandro , Mayoral José Antonio , García-Peiro José Ignacio , Velázquez David
Published: November 2018

We present an efficient and green methodology for the synthesis of glycerol monoethers, starting from glycidol and different alcohols, by means of heterogeneous acid catalysis. A scope of Brønsted and Lewis acid catalysts were applied to the benchmark reaction of glycidol and methanol. The selected catalysts were cationic exchangers, such as Nafion NR50, Dowex 50WX2, Amberlyst 15 and K10-Montmorillonite, both in their protonic form and exchanged with Al(III), Zn(II) and Fe(III). Thus, total conversions were reached in short times by using 1 and 5% mol catalyst loading and room temperature, without the need for excess glycidol or the presence of a solvent. Finally, these conditions and the best catalysts were successfully applied to the reaction of glycidol with several alcohols such as butanol or isopropanol.
A Turn-On Detection of DNA Sequences by Means of Fluorescence of DNA-Templated Silver Nanoclusters via Unique Interactions of a Hydrated Ionic Liquid
Authors: Teng Ye , Tateishi-Karimata Hisae , Tsuruoka Takaaki , Sugimoto Naoki
Published: November 2018

Nucleic acid stability and structure, which are crucial to the properties of fluorescent DNA-templated silver nanoclusters (DNA-Ag NCs), significantly change in ionic liquids. In this work, our purpose was to study DNA-Ag NCs in a buffer containing the hydrated ionic liquid of choline dihydrogen phosphate (choline dhp) to improve fluorescence for application in DNA detection. Due to the stabilisation of an i-motif structure by the choline cation, a unique fluorescence emission—that was not seen in an aqueous buffer—was observed in choline dhp and remained stable for more than 30 days. A DNA-Ag NCs probe was designed to have greater fluorescence intensity in choline dhp in the presence of a target DNA. A turn-on sensing platform in choline dhp was built for the detection of the BRCA1 gene, which is related to familial breast and ovarian cancers. This platform showed better sensitivity and selectivity in distinguishing a target sequence from a mutant sequence in choline dhp than in the aqueous buffer. Our study provides new evidence regarding the effects of structure on properties of fluorescent DNA-Ag NCs and expands the applications of fluorescent DNA-Ag NCs in an ionic liquid because of improved sensitivity and selectivity.
Extraction and Analysis of Phenolic Compounds in Rice: A Review
Authors: Ciulu Marco , Cádiz-Gurrea Maria de la Luz , Segura-Carretero Antonio
Published: November 2018

Rice represents the main source of calorie intake in many world countries and about 60% of the world population include rice in their staple diet. Whole grain rice, also called brown rice, represent the unpolished version of the more common white rice including bran, germ, and endosperm. Many health-promoting properties have been associated to the consumption of whole grain rice and, for this reason, great attention has been paid by the scientific community towards the identification and the quantification of bioactive compounds in this food item. In this contribution, the last five years progresses in the quali-quantitative determination of phenolic compounds in rice have been highlighted. Special attention has been devoted to the most recent strategies for the extraction of the target compounds from rice along with the analytical approaches adopted for the separation, identification and quantification of phenolic acids, flavonoids, anthocyanins, and proanthocyanidins. More specifically, the main features of the “traditional” extraction methods (i.e., maceration, ultrasound-assisted extraction) have been described, as well as the more innovative protocols involving advanced extraction techniques, such as MAE (microwave-assisted extraction). The predominant role of HPLC in the definition of the phenolic profile has been examined also presenting the most recent results obtained by using mass spectrometry-based detection systems. In addition, the most common procedures aimed to the quantification of the total amount of the cited classes of phenolic compounds have been described together with the spectrophotometric protocols aimed to the evaluation of the antioxidant properties of rice phenolic extracts (i.e., FRAP, DPPH, ABTS and ORAC).
Phosphorus Solubilization by Bacillus Species
Authors: Saeid Agnieszka , Prochownik Ewelina , Dobrowolska-Iwanek Justyna
Published: November 2018

Microbial solubilization applies the natural ability of a microorganism to liberate phosphorus from unavailable structures. The main mechanism recognized to be responsible for the solubilization of phosphorus is the production of different types of organic acids. Three kinds of Bacillus species and three types of raw materials (poultry bones, fish bones, and ash) were tested for solubilization. The following parameters were compared for all discussed cases: pH, specific growth rate, solubilization factor, released phosphorus concentration, and total and individual concentration of organic acids. Utilization of ash brought about the highest specific and maximum specific growth rates. A decrease in pH was observed in most of the discussed cases with the exception of fish bones. At the same time, fish bones had the highest concentration of released P2O5 and the highest total concentration of produced organic acids (gluconic, lactic, acetic, succinic, and propionic) in all discussed cases. The tested Bacillus species produced the mentioned acids with the exception of B. megaterium, where propionic acid was not present. The lactic and acetic acids were those produced in the highest amount. The kind of raw materials and type of Bacillus species used in solubilization had a strong influence on the kind of organic acids that were detected in the broth culture and its total concentration, which had a direct influence on the amount of released phosphorus. The combination of Bacillus megaterium with the fish bones at 5 g/L is proposed as the pair that gives the highest concentration of released phosphorus (483 ± 5 mg/L).
Site-Specific Labeling of Proteins with Near-IR Heptamethine Cyanine Dyes
Authors: Lin Chen-Ming , Usama Syed Muhammad , Burgess Kevin
Published: November 2018

Convenient labeling of proteins is important for observing its function under physiological conditions. In tissues particularly, heptamethine cyanine dyes (Cy-7) are valuable because they absorb in the near-infrared (NIR) region (750–900 nm) where light penetration is maximal. In this work, we found Cy-7 dyes with a meso-Cl functionality covalently binding to proteins with free Cys residues under physiological conditions (aqueous environments, at near neutral pH, and 37 °C). It transpired that the meso-Cl of the dye was displaced by free thiols in protein, while nucleophilic side-chains from amino acids like Tyr, Lys, and Ser did not react. This finding shows a new possibility for convenient and selective labeling of proteins with NIR fluorescent probes.
Synthesis of Jacaranone-Derived Nitrogenous Cyclohexadienones and Their Antiproliferative and Antiprotozoal Activities
Authors: Presser Armin , Lainer Gunda , Kretschmer Nadine , Schuehly Wolfgang , Saf Robert , Kaiser Marcel , Kalt Marc-Manuel
Published: November 2018

The cytotoxic and antiprotozoal activities of the phytoquinoide, jacaranone, and related compounds have been an ongoing topic in recent drug discovery. Starting from the natural product-derived cyclohexadienone scaffold, a series of nitrogen-containing derivatives were synthesized and subsequently evaluated for their antiproliferative and antiprotozoal activity. Anticancer potency was analyzed using different types of cancer cell lines: MDA-MB-231 breast cancer, CCRF-CEM leukemia, HCT-116 colon cancer, U251 glioblastoma, and, in addition, non-tumorigenic MRC-5 lung fibroblasts. Antiproliferative activities at micromolar concentrations could be shown. Antiprotozoal activity was assessed against Plasmodium falciparum NF54 and Trypanosoma brucei rhodesiense STIB900. For all compounds, selectivity indices (SI) were calculated based on assessed cytotoxicity towards L6 cells. In addition, the structure-activity-relationships and physicochemical parameters of these compounds are discussed.
Anti-Cancer Drug Sensitivity Assay with Quantitative Heterogeneity Testing Using Single-Cell Raman Spectroscopy
Authors: Zhang Yong , Xu Jingjing , Yu Yuezhou , Shang Wenhao , Ye Anpei
Published: November 2018

A novel anti-cancer drug sensitivity testing (DST) approach was developed based on in vitro single-cell Raman spectrum intensity (RSI). Generally, the intensity of Raman spectra (RS) for a single living cell treated with drugs positively relates to the sensitivity of the cells to the drugs. In this study, five cancer cell lines (BGC 823, SGC 7901, MGC 803, AGS, and NCI-N87) were exposed to three cytotoxic compounds or to combinations of these compounds, and then they were evaluated for their responses with RSI. The results of RSI were consistent with conventional DST methods. The parametric correlation coefficient for the RSI and Methylthiazolyl tetrazolium assay (MTT) was 0.8558 ± 0.0850, and the coefficient of determination was calculated as R2 = 0.9529 ± 0.0355 for fitting the dose–response curve. Moreover, RSI data for NCI-N87 cells treated by trastuzumab, everolimus (cytostatic), and these drugs in combination demonstrated that the RSI method was suitable for testing the sensitivity of cytostatic drugs. Furthermore, a heterogeneity coefficient H was introduced for quantitative characterization of the heterogeneity of cancer cells treated by drugs. The largest possible variance between RSs of cancer cells were quantitatively obtained using eigenvalues of principal component analysis (PCA). The ratio of H between resistant cells and sensitive cells was greater than 1.5, which suggested the H-value was effective to describe the heterogeneity of cancer cells. Briefly, the RSI method might be a powerful tool for simple and rapid detection of the sensitivity of tumor cells to anti-cancer drugs and the heterogeneity of their responses to these drugs.
Gas Phase Hydrogenation of Furaldehydes via Coupling with Alcohol Dehydrogenation over Ceria Supported Au-Cu
Authors: Pischetola Chiara , Collado Laura , Keane Mark A. , Cárdenas-Lizana Fernando
Published: November 2018

We have investigated the synthesis and application of Au-Cu/CeO2 (Cu: Au = 2) in the continuous gas phase (P = 1 atm; T = 498 K) coupled hydrogenation of 5-hydroxymethyl-2-furaldehyde (HMF) with 2-butanol dehydrogenation. STEM-EDX analysis revealed a close surface proximity of both metals in Au-Cu/CeO2 post-TPR. XPS measurements suggest (support → metal) charge transfer to form Auδ− and strong metal-support interactions to generate Cu0 and Cu+. Au-Cu/CeO2 promoted the sole formation of 2,5-dihydroxymethylfuran (DHMF) and 2-butanone in the HMF/2-butanol coupling with full hydrogen utilisation. Under the same reaction conditions, Au/CeO2 was fully selective to DHMF in standard HMF hydrogenation (using an external hydrogen supply), but delivered a lower production rate and utilised less than 0.2% of the hydrogen supplied. Exclusive -C=O hydrogenation and -OH dehydrogenation is also demonstrated for the coupling of a series of m-substituted (-CH3, -CH2CH3, -CH2OH, -CF3, -N(CH3)2, -H) furaldehydes with alcohol (1-propanol, 1-butanol, 2-propanol, 2-butanol, cyclohexanol) dehydrogenation over Au-Cu/CeO2, consistent with a nucleophilic mechanism. In each case, we observed a greater hydrogenation rate and hydrogen utilisation efficiency with a 3–15 times lower E-factor in the coupling process relative to standard hydrogenation. Our results demonstrate the feasibility of using hydrogen generated in situ through alcohol dehydrogenation for the selective hydrogenation of m-furaldehydes with important industrial applications.
Variety Identification of Raisins Using Near-Infrared Hyperspectral Imaging
Authors: Feng Lei , Zhu Susu , Zhang Chu , Bao Yidan , Gao Pan , He Yong
Published: November 2018

Different varieties of raisins have different nutritional properties and vary in commercial value. An identification method of raisin varieties using hyperspectral imaging was explored. Hyperspectral images of two different varieties of raisins (Wuhebai and Xiangfei) at spectral range of 874–1734 nm were acquired, and each variety contained three grades. Pixel-wise spectra were extracted and preprocessed by wavelet transform and standard normal variate, and object-wise spectra (sample average spectra) were calculated. Principal component analysis (PCA) and independent component analysis (ICA) of object-wise spectra and pixel-wise spectra were conducted to select effective wavelengths. Pixel-wise PCA scores images indicated differences between two varieties and among different grades. SVM (Support Vector Machine), k-NN (k-nearest Neighbors Algorithm), and RBFNN (Radial Basis Function Neural Network) models were built to discriminate two varieties of raisins. Results indicated that both SVM and RBFNN models based on object-wise spectra using optimal wavelengths selected by PCA could be used for raisin variety identification. The visualization maps verified the effectiveness of using hyperspectral imaging to identify raisin varieties.
Complete Chloroplast Genome Sequence of Malus hupehensis: Genome Structure, Comparative Analysis, and Phylogenetic Relationships
Authors: Zhang Xin , Rong Chunxiao , Qin Ling , Mo Chuanyuan , Fan Lu , Yan Jie , Zhang Manrang
Published: November 2018

Malus hupehensis belongs to the Malus genus (Rosaceae) and is an indigenous wild crabapple of China. This species has received more and more attention, due to its important medicinal, and excellent ornamental and economical, values. In this study, the whole chloroplast (cp) genome of Malus hupehensis, using a Hiseq X Ten sequencing platform, is reported. The M. hupehensis cp genome is 160,065 bp in size, containing a large single copy region (LSC) of 88,166 bp and a small single copy region (SSC) of 19,193 bp, separated by a pair of inverted repeats (IRs) of 26,353 bp. It contains 112 genes, including 78 protein-coding genes (PCGs), 30 transfer RNA genes (tRNAs), and four ribosomal RNA genes (rRNAs). The overall nucleotide composition is 36.6% CG. A total of 96 simple sequence repeats (SSRs) were identified, most of them were found to be mononucleotide repeats composed of A/T. In addition, a total of 49 long repeats were identified, including 24 forward repeats, 21 palindromic repeats, and four reverse repeats. Comparisons of the IR boundaries of nine Malus complete chloroplast genomes presented slight variations at IR/SC boundaries regions. A phylogenetic analysis, based on 26 chloroplast genomes using the maximum likelihood (ML) method, indicates that M. hupehensis clustered closer ties with M. baccata, M. micromalus, and M. prunifolia than with M. tschonoskii. The availability of the complete chloroplast genome using genomics methods is reported here and provides reliable genetic information for future exploration on the taxonomy and phylogenetic evolution of the Malus and related species.
A Novel Venom-Derived Peptide for Brachytherapy of Glioblastoma: Preclinical Studies in Mice
Authors: Swenson Steve , Minea Radu O. , Tuan Cao Duc , Thein Thu-Zan , Chen Thomas C. , Markland Francis S.
Published: November 2018

We developed a bacterial expression system to produce a recombinant disintegrin, vicrostatin (VCN), whose structure is based on a natural disintegrin isolated from southern copperhead snake venom. Our goal is to develop VCN for potential clinical translation as an anti-cancer agent. VCN is a peptide of 69 amino acids with a single tyrosine residue. We have employed VCN as integrin-targeted radionuclide therapy (brachytherapy) for treatment of glioblastoma (GBM, glioma). GBM is a deadly brain cancer that doesn’t discriminate between sexes and knows no age limit. We established that the tyrosine residue in VCN can be radioiodinated with full retention of bioactivity. 131I-VCN was utilized for integrin-targeted radionuclide therapy using mouse models of glioma. The combination of radioiodinated VCN plus temozolomide (a DNA alkylating agent) significantly prolonged survival of glioma-bearing mice. We also obtained similar results using an immunocompetent mouse model and a murine glioma cell line. In summary, as demonstrated in studies reported here we have shown that VCN as targeted radionuclide therapy for GBM has significant translational potential for therapy of this deadly disease.
A Broadband Phototransistor Based on Three-Dimensional Reduced Graphene Oxide Foam
Authors: Li Yifan , Zhang Yating , Yu Yu , Chen Zhiliang , Jin Lufan , Cao Mingxuan , Dai Haitao , Yao Jianquan
Published: November 2018

Three-dimensional (3D) cross-linked polymer-like reduced graphene oxide foams (rGOFs) with a seamlessly continuous graphene network, exhibit high photoresponsive and conductivity and have received much attention regarding solar cells and supercapacitors. However, little attention has been paid to photodetection applications of 3D rGOFs. Here we report a novel broadband phototransistor based on metal-3D GFs-metal, which exhibits a high light absorption and a wide spectra response ranging at least from 400 to 1600 nm wavelength with a maximum photoresponsivity of 10 mA/W at 400 nm. In particular, stable and reproducible photocurrent cycles are achieved under different light blue light (405 nm), green light (532 nm), and NIR (808 nm) irradiations. Moreover, the device displays a typical transistor characteristic with a rapid response time of 18 ms at under 532 nm irradiation. The excellent performances indicate 3D rGOF as a promising candidate for future photodetection application.
Light-Tuned DC Conductance of Anatase TiO2 Nanotubular Arrays: Features of Long-Range Charge Transport
Authors: Zimnyakov Dmitry A. , Vasilkov Michail Yu. , Yuvchenko Sergey A. , Varezhnikov Alexey S. , Sommer Martin , Sysoev Victor V.
Published: November 2018

Experimental results related to the photoactivated dc conductance of anatase TiO2 nanotubular arrays (aTNTAs) under pulsed irradiation by a laser light inside and outside the fundamental absorption band are presented. It is found that the mobility and diffusion coefficients of charge carriers in the examined aTNTA are extremely low due to a strong charge-phonon coupling, abundance of shallow traps, and hopping conductivity between adjacent nanotubes. We consider that the confining electric field appeared within the array structure due to the difference in the local concentrations of excess electrons and holes at large values of the dc conductance suppresses the drift current. In this case, the dc conductance of such aTNTAs is mainly matured by the diffusion of mobile carriers. A recurrent kinetic model for evolution of the dc conductance of aTNTAs under laser irradiation has been proposed to interpret the experimental results.
Ultrastructural Remodeling of the Neurovascular Unit in the Female Diabetic db/db Model—Part III: Oligodendrocyte and Myelin
Authors: Hayden Melvin , Grant Deana , Aroor Aranyra , DeMarco Vincent
Published: November 2018

Obesity, insulin resistance, and type 2 diabetes mellitus are associated with diabetic cognopathy. In this study, we tested the hypothesis that neurovascular unit(s) (NVU), oligodendrocytes, and myelin within cerebral cortical grey matter and deeper transitional zone regions between the cortical grey matter and white matter may be abnormal. The monogenic (Leprdb) female diabetic db/db [BKS.CgDock7m +/+ Leprdb/J] (DBC) mouse model was utilized for this ultrastructural study. Upon sacrifice (20 weeks of age), left-brain hemispheres of the DBC and age-matched non-diabetic wild type control C57BL/KsJ (CKC) mice were immediately immersion-fixed. We found prominent remodeling of oligodendrocytes with increased nuclear chromatin condensation and volume and increased numbers of active myelination sites of the cytoplasm in transition zones. Marked dysmyelination with outer myelin lamellae sheath splitting, separation, and ballooning with aberrant mitochondria in grey matter and similar myelin remodeling changes with marked disarray with additional axonal collapse in transitional zones in DBC as compared to CKC models.