bluuebunny/crossref_metadata_2025 huggingface dataset:
Substituting the catalytic proline of 4-oxalocrotonate tautomerase with non-canonical analogues reveals a finely tuned catalytic system
Authors: Lukesch Michael S. , Pavkov-Keller Tea , Gruber Karl , Zangger Klaus , Wiltschi Birgit
Published: February 2019

The enzyme 4-oxalocrotonate tautomerase shows remarkable catalytic versatility due to the secondary amine of its N-terminal proline moiety. In this work, we incorporated a range of proline analogues into the enzyme and examined the effects on structure and activity. While the structure of the enzyme remained unperturbed, its promiscuous Michael-type activity was severely affected. This finding demonstrates how atomic changes in a biocatalytic system can abolish its activity. Our work provides a toolbox for successful generation of enzyme variants with non-canonical catalytic proline analogues.
A hindbrain inhibitory microcircuit mediates vagally-coordinated glucose regulation
Authors: Boychuk Carie R. , Smith Katalin Cs. , Peterson Laura E. , Boychuk Jeffery A. , Butler Corwin R. , Derera Isabel D. , McCarthy John J. , Smith Bret N.
Published: February 2019

Neurons in the brainstem dorsal vagal complex integrate neural and humoral signals to coordinate autonomic output to viscera that regulate a variety of physiological functions, but how this circuitry regulates metabolism is murky. We tested the hypothesis that premotor, GABAergic neurons in the nucleus tractus solitarius (NTS) form a hindbrain micro-circuit with preganglionic parasympathetic motorneurons of the dorsal motor nucleus of the vagus (DMV) that is capable of modulating systemic blood glucose concentration. In vitro, neuronal activation or inhibition using either excitatory or inhibitory designer receptor exclusively activated by designer drugs (DREADDs) constructs expressed in GABAergic NTS neurons increased or decreased, respectively, action potential firing of GABAergic NTS neurons and downstream synaptic inhibition of the DMV. In vivo, DREADD-mediated activation of GABAergic NTS neurons increased systemic blood glucose concentration, whereas DREADD-mediated silencing of these neurons was without effect. The DREADD-induced hyperglycemia was abolished by blocking peripheral muscarinic receptors, consistent with the hypothesis that altered parasympathetic drive mediated the response. This effect was paralleled by elevated serum glucagon and hepatic phosphoenolpyruvate carboxykinase 1 (PEPCK1) expression, without affecting insulin levels or muscle metabolism. Activity in a hindbrain inhibitory microcircuit is sufficient to modulate systemic glucose concentration, independent of insulin secretion or utilization.
Modelling Holocene analogues of coastal plain estuaries reveals the magnitude of sea-level threat
Authors: Helfensdorfer Anna M. , Power Hannah E. , Hubble Thomas C. T.
Published: February 2019

Hydrodynamic modelling of Australia’s lower Murray River demonstrates the response of a large coastal plain estuary to the mid-Holocene (7,000–6,000 yr BP) sea-level highstand. The approximately two metre higher-than-present sea level during the highstand forced the estuarine limit upstream generating an extensive central basin environment extending more than 200 kilometres from the river mouth (143 kilometres upstream of the modern tidal limit). The geomorphic history of the region does not conform to conventional estuarine facies models as, for much of the Holocene, the lower Murray River acted as a landward, gorge-confined extension of the Murray estuary. The incredibly low relief of this coastal plain system drove significant saline incursion and limited current velocities across the estuary facilitating deposition of a laminated silt-clay sequence which our results suggest may be regionally extensive. Variations to discharge, barrier morphology, or the estuary’s bathymetry result in minimal change to the estuarine palaeo-environment. The shift to the present-day fresher water distribution in the Murray estuary requires a fall in sea level to present-day conditions. The dominance of sea level as the controlling factor on this estuarine palaeo-environment highlights the significant potential impact of climate change induced sea-level rise to coastal plain estuaries.
Associations of maternal, perinatal and postnatal factors with the eruption timing of the first primary tooth
Authors: Wu Huaying , Chen Ting , Ma Qian , Xu Xiangqin , Xie Kaipeng , Chen Yaming
Published: February 2019

We recruited 1296 mothers in their first trimester from the Affiliated Obstetrics and Gynecology Hospital of Nanjing Medical University between May 2014 and September 2015 to investigate the associations of maternal, perinatal and postnatal factors with the eruption timing of the first primary tooth (ETFPT) in a Chinese population. We collected maternal demographic information and clinical data during the perinatal and postnatal period, and oral examinations of the infants were performed by a doctor at 6, 9 and 12 months of age. Multiple regression analysis was used to identify significant explanatory variables for ETFPT. The mean age at eruption of the first primary tooth for all the infants was 6.82 ± 1.90 months. After adjustment for confounders, higher maternal childbearing age (β = 0.57; 95%CI = 0.13–1.02), female sex (β = 0.26; 95%CI = 0.07–0.52), and low birth weight (β = 0.98; 95%CI = 0.20–1.76) were significantly associated with delayed eruption of the first primary tooth, while macrosomia (β = −0.79; 95%CI = −1.30–−0.28) was significantly associated with earlier eruption of the first primary tooth. Maternal childbearing age, infant sex and infant birth weight were significant determinants of ETFPT.
Vascular RAGE transports oxytocin into the brain to elicit its maternal bonding behaviour in mice
Authors: Yamamoto Yasuhiko , Liang Mingkun , Munesue Seiichi , Deguchi Kisaburo , Harashima Ai , Furuhara Kazumi , Yuhi Teruko , Zhong Jing , Akther Shirin , Goto Hisanori , Eguchi Yuya , Kitao Yasuko , Hori Osamu , Shiraishi Yoshitake , Ozaki Noriyuki , Shimizu Yu , Kamide Tomoya , Yoshikawa Akifumi , Hayashi Yasuhiko , Nakada Mitsutoshi , Lopatina Olga , Gerasimenko Maria , Komleva Yulia , Malinovskaya Natalia , Salmina Alla B. , Asano Masahide , Nishimori Katsuhiko , Shoelson Steven E. , Yamamoto Hiroshi , Higashida Haruhiro
Published: February 2019

Oxytocin sets the stage for childbirth by initiating uterine contractions, lactation and maternal bonding behaviours. Mice lacking secreted oxcytocin (Oxt−/−, Cd38−/−) or its receptor (Oxtr−/−) fail to nurture. Normal maternal behaviour is restored by peripheral oxcytocin replacement in Oxt−/− and Cd38−/−, but not Oxtr−/− mice, implying that circulating oxcytocin crosses the blood-brain barrier. Exogenous oxcytocin also has behavioural effects in humans. However, circulating polypeptides are typically excluded from the brain. We show that oxcytocin is transported into the brain by receptor for advanced glycation end-products (RAGE) on brain capillary endothelial cells. The increases in oxcytocin in the brain which follow exogenous administration are lost in Ager−/− male mice lacking RAGE, and behaviours characteristic to abnormalities in oxcytocin signalling are recapitulated in Ager−/− mice, including deficits in maternal bonding and hyperactivity. Our findings show that RAGE-mediated transport is critical to the behavioural actions of oxcytocin associated with parenting and social bonding.
MALDI-TOF MS-based total serum protein fingerprinting for liver cancer diagnosis
Authors: Park Han-Gyu , Jang Kyoung-Soon , Park Hae-Min , Song Won-Suk , Jeong Yoon-Yi , Ahn Da-Hee , Kim Seong-Min , Yang Yung-Hun , Kim Yun-Gon
Published: February 2019

Serum is one of the most commonly used samples in many studies to identify protein biomarkers to diagnose cancer.
Formation of maghemite nanostructures in polyol: tuning the particle size via the precursor stoichiometry
Authors: Wetegrove Marcel , Witte Kerstin , Bodnar Wiktor , Pfahl Dan-Eric , Springer Armin , Schell Norbert , Westphal Fritz , Burkel Eberhard
Published: February 2019

Investigating the polyol-assisted synthesis of maghemite nanoflowers, a strong impact of the iron precursor stoichiometry on physical properties is found.
Evaluation of labeling methods used for investigating the environmental behavior and toxicity of metal oxide nanoparticles
Authors: Deline Alyssa R. , Nason Jeffrey A.
Published: February 2019

The analysis of the environmental behavior and toxicity of metal oxide nanoparticles (MONPs) is complicated by high metal concentrations in natural matrices.
Luminescence thermometry for in situ temperature measurements in microfluidic devices
Authors: Geitenbeek Robin G. , Vollenbroek Jeroen C. , Weijgertze Hannah M. H. , Tregouet Corentin B. M. , Nieuwelink Anne-Eva , Kennedy Chris L. , Weckhuysen Bert M. , Lohse Detlef , van Blaaderen Alfons , van den Berg Albert , Odijk Mathieu , Meijerink Andries
Published: February 2019

In this work we present 3 showcases that luminescence thermometry is a promising and versatile technique for temperature monitoring in various microfluidic devices.
An electric-field-dependent drop selector
Authors: Yang Jinlong , Wang Dehui , Liu Hailong , Li Linxian , Chen Longquan , Jiang Hong-Ren , Deng Xu
Published: February 2019

We have designed a superhydrophobic-coated chip to manipulate the static and dynamic behaviors of a drop using dielectrowetting.
Key aspects of the iodine metabolism in brown algae: a brief critical review
Authors: Küpper Frithjof C , Carrano Carl J
Published: February 2019

Brown algae include the strongest accumulators of iodine known among living systems. This paper reviews the current state of bioinorganic research in the field, focusing on the models Laminaria digitata, Macrocystis pyrifera and Ectocarpus siliculosus, and covering uptake and efflux, localization and biological significance of storage, as well as marine and atmospheric chemistry of iodine.
Catalytic properties of the metal ion variants of mandelate racemase reveal alterations in the apparent electrophilicity of the metal cofactor
Authors: Harty Matthew L , Sharma Amar Nath , Bearne Stephen L
Published: February 2019

Mandalate racemase (MR) from Pseudomonas putida requires a divalent metal cation, usually Mg2+, to catalyse the interconversion of the enantiomers of mandelate. Although the active site Mg2+ may be replaced by Mn2+, Co2+, or Ni2+, substitution by these metal ions does not markedly (<10-fold) alter the kinetic parameters Kmapp, Kcatapp, and (kcat/Km)app for the substrates (R)- and (S)-mandelate, and the alternative substrate (S)-trifluorolactate. Viscosity variation experiments with Mn2+-MR showed that the metal ion plays a role in the uniform binding of the transition states for enzyme–substrate association, the chemical step, and enzyme-product dissociation. Surprisingly, the competitive inhibition constants (Ki) for inhibition of each metalloenzyme variant by benzohydroxamate did not vary significantly with the identity of the metal ion unlike the marked variation of the stability constants (K1) observed for M2+·BzH complex formation in solution. A similar trend was observed for the inhibition of the metalloenzyme variants by F−, except for Mg2+-MR, which bound F− tighter than would be predicted based on the stability constants for formation of M2+·F− complexes in solution. Thus, the enzyme modifies the enatic state of the bound metal ion cofactor so that the apparent electrophilicity of Mg2+ is enhanced, while that of Ni2+ is attenuated, resulting in a levelling effect relative to the trends observed for the free metals in solution.
CO2 capture by a novel CaO/MgO sorbent fabricated from industrial waste and dolomite under calcium looping conditions
Authors: Yan Xianyao , Li Yingjie , Ma Xiaotong , Zhao Jianli , Wang Zeyan , Liu Hantao
Published: February 2019

A synthetic sorbent prepared from carbide slag and dolomite by combustion exhibits high CO2 capture capacity, good cyclic stability and a porous microstructure.
Crucial successes in drug delivery systems using multivariate chemometric approaches: challenges and opportunities
Authors: Etezadi Haniyeh , Sajjadi S. Maryam , Maleki Aziz
Published: February 2019

Applying multivariate chemometric methods for thorough investigation of three processes in drug delivery systems: loading, release and photo-degradation.
Repurposing of antidepression drug sertraline for antimicrobial activity againstStaphylococcus aureus: a potential approach for the treatment of osteomyelitis
Authors: Muthu D. , Gowri M. , Suresh Kumar G. , Kattimani V. S. , Girija E. K.
Published: February 2019

We report a potential approach to synthesize the repurposed sertraline drug-loaded hydroxyapatite nanoparticles using eggshell as the calcium sourceviathein situprecipitation method for the treatment of osteomyelitis.
Water-stable and ion exchange-free inorganic perovskite quantum dots encapsulated in solid paraffin and their application in light emitting diodes
Authors: Wu Haishan , Lin Shan , Wang Ruina , You Xu , Chi Yuwu
Published: February 2019

Perovskite quantum dots encapsulated in solid paraffin (P-PQDs) are water-stable and ion exchange-free, and show promising application in LEDs.
Binder-free SnO2–TiO2 composite anode with high durability for lithium-ion batteries
Authors: Yoo Hyeonseok , Lee Gibaek , Choi Jinsub
Published: February 2019

A binder-free SnO2–TiO2 composite, where SnO2 is encapsulated into hollow TiO2, is designed for inhibiting performance degradation for a stable LIB anode.
3D printing of thermoreversible polyurethanes with targeted shape memory and precise in situ self-healing properties
Authors: Zhang Yue , Yin Xiang-Yu , Zheng Mingyue , Moorlag Carolyn , Yang Jun , Wang Zhong Lin
Published: February 2019

3D printable thermoreversible polyurethanes (PDAPUs) are synthesized, which facilitate the manufacturing of smart devices with 3D structures. The cross-linking of aniline trimer in PDAPUs plays a critical role in realizing light controllable precise selfhealing and targeted shape memory.
Electrical energy generated by silicone elastomers filled with nanospring-carbon-nanotubes
Authors: Lee Yun Jae , Caspari Philip , Opris Dorina M. , Nüesch Frank A. , Ham Sora , Kim Jung-Hyuk , Kim Sung-Ryong , Ju Byeong-Kwon , Choi Won Kook
Published: February 2019

Novel silicone composites with increased dielectric permittivity were tested as dielectric in electret dielectric elastomer generators and gave a voltage when stretched.
Construction of an ultrasensitive electrochemiluminescent aptasensor for ractopamine detection
Authors: Xiong Huiwen , Gao Jingwen , Wang Ying , Chen Ziyi , Chen Miao-Miao , Zhang Xiuhua , Wang Shengfu
Published: February 2019

An ultrasensitive ECL aptasensor was designed for ractopamine detection.
Simultaneous determination of major peanut allergens Ara h1 and Ara h2 in baked foodstuffs based on their signature peptides using ultra-performance liquid chromatography coupled to tandem mass spectrometry
Authors: Zhang Jingshun , Hong Yuwei , Cai Zengxuan , Huang Baifen , Wang Junlin , Ren Yiping
Published: February 2019

A robust UPLC-MS/MS method was established for the quantitative analysis of the major peanut allergens Ara h1 and Ara h2 in baked foodstuffs based on their signature peptides.
Crystal-to-crystal interconversion of open and closed dicopper(ii) paddle wheels in a heterotrimetallic coordination polymer
Authors: Ohwaki Hayato , Yoshinari Nobuto , Konno Takumi
Published: February 2019

A dicopper(ii) paddle-wheel system that shows a unique magnetic loop induced by crystal-to-crystal structural transformation is reported.
Underwater manipulation of oil droplets and bubbles on superhydrophobic surfaces via switchable adhesion
Authors: Gao Dejun , Cao Jian , Guo Zhiguang
Published: February 2019

UV light-responsive reversible switching of oil droplet and bubble adhesion underwater is realized to manipulate oil droplet or bubble motion and transportation.
Silylene induced cooperative B–H bond activation and unprecedented aldehyde C–H bond splitting with amidinate ring expansion
Authors: Swamy V. S. V. S. N. , Raj K. Vipin , Vanka Kumar , Sen Sakya S. , Roesky Herbert W.
Published: February 2019

Silylene mediated B–H and aldehyde C–H bond splitting were realized under ambient conditions.
Proton-coupled electron transfer oxidation of O–H bond by the N-radical cation of Wurster's blue salt (TMPDA˙+)
Authors: Li Han , Guo Yu-Hua , Wu Jun-Yan , Zhang Ming-Tian
Published: February 2019

Beyond a single electron oxidant, the N-radical cation is also a good PCET reagent.
Straightforward access to biocompatible poly(2-oxazoline)-coated nanomaterials by polymerization-induced self-assembly
Authors: Le Dao , Wagner Friederike , Takamiya Masanari , Hsiao I-Lun , Gil Alvaradejo Gabriela , Strähle Uwe , Weiss Carsten , Delaittre Guillaume
Published: February 2019

Poly(2-ethyl-2-oxazoline) chain transfer agents are employed in photoinitiated RAFT PISA, providing access to biocompatible core–shell polymeric nanostructures with various morphologies.
Ratiometric fluorescent probe for sensing Streptococcus mutans glucosyltransferase, a key factor in the formation of dental caries
Authors: Feng Lei , Yan Qingsong , Zhang Baojing , Tian Xiangge , Wang Chao , Yu Zhenlong , Cui Jingnan , Guo Dean , Ma Xiaochi , James Tony D.
Published: February 2019

A naphthalimide-based ratiometric fluorescent probe was designed for sensing (and inhibitor screening) of pathogenic bacterial glucosyltransferases associated with the formation of dental caries.
Improved single-chain-magnet behavior in a biradical-based nitronyl nitroxide-Cu–Dy chain
Authors: Xie Jing , Li Hong-Dao , Yang Meng , Sun Juan , Li Li-Cun , Sutter Jean-Pascal
Published: February 2019

The first example of nitronyl nitroxide biradical bridged 3d–4f complex exhibiting single-chain magnet behavior.
Direct conversion of cellulose into ethanol catalysed by a combination of tungstic acid and zirconia-supported Pt nanoparticles
Authors: Song Haiyan , Wang Pan , Li Shi , Deng Weiping , Li Yanyun , Zhang Qinghong , Wang Ye
Published: February 2019

Direct conversion of cellulose to ethanol is achieved by using a combination of H2WO4 and Pt/ZrO2 catalysts in an aqueous medium.
The transformation of anatase TiO2 to TiSe2 to form TiO2–TiSe2 composites for Li+/Na+ storage with improved capacities
Authors: Li Pengchao , Chen Changmiao , Huang Zhao , Cai Yong , Zhang Ming
Published: February 2019

We discovered and explored the basic conditions for the conversion of TiO2-A to TiSe2 and tested its electrochemical performance.
Thermophysical properties of glyceline–water mixtures investigated by molecular modelling
Authors: Baz Jörg , Held Christoph , Pleiss Jürgen , Hansen Niels
Published: February 2019

Water activity and shear viscosity of water–glyceline mixtures are important process parameters that can be effectively calculated using molecular modelling.
Manipulation of dipolar magnetism in low-dimensional iron oxide nanoparticle assemblies
Authors: Wang Li-Ming , Qdemat Asma , Petracic Oleg , Kentzinger Emmanuel , Rücker Ulrich , Zheng Fengshan , Lu Peng-Han , Wei Xian-Kui , Dunin-Borkowski Rafal E. , Brückel Thomas
Published: February 2019

Trench-patterned iron oxide nanoparticles are switched between a superspin glass and a superferromagnetic state.
Reversible borohydride formation from aluminium hydrides and {H(9-BBN)}2: structural, thermodynamic and reactivity studies
Authors: Caise Alexa , Kolychev Eugene L. , Hicks Jamie , Fuentes M. Ángeles , Goicoechea Jose M. , Aldridge Simon
Published: February 2019

Aluminium borohydrides of the type (Nacnac)Al(R){H2(9-BBN)} are characterized by borane dissociation in solution under ambient conditions. This behaviour is critical to the ability of such complexes to reduce CO2.
Anionic guest-dependent slow magnetic relaxation in Co(ii) tripodal iminopyridine complexes
Authors: Klug Christina M. , Ozumerzifon Tarik J. , Bhowmick Indrani , Livesay Brooke N. , Rappé Anthony K. , Shores Matthew P.
Published: February 2019

We explore structural and magnetic changes on mononuclear cobalt(ii) complex salts featuring a tripodal iminopyridine ligand imparted by second coordination sphere anions.
High Curie temperature and intrinsic ferromagnetic half-metallicity in two-dimensional Cr3X4 (X = S, Se, Te) nanosheets
Authors: Zhang Xiwen , Wang Bing , Guo Yilv , Zhang Yehui , Chen Yunfei , Wang Jinlan
Published: February 2019

High Curie temperature in two-dimensional ferromagnetic half-metals is attainable via double-exchange interaction.
Sensitive colorimetric detection of CN− and AcO− anions in a semi-aqueous environment through a coumarin–naphthalene conjugate azo dye
Authors: Dwivedi Sushil K. , Razi Syed S. , Misra Arvind
Published: February 2019

An efficient colorimetric chemosensor to detect anions in an aqueous medium.
pH-regulated synthesis of CuOx/ERGO nanohybrids with tunable electrocatalytic oxidation activity towards nitrite sensing
Authors: Yue Xiaoyue , Luo Xiaoyu , Zhou Zijun , Wu Yongmei , Bai Yanhong
Published: February 2019

CuOx/ERGO nanohybrids with diverse morphologies prepared by pH-regulated synthesis display tunable electrocatalytic ability towards nitrite sensing.
Rapid formation of small mixed-valence luminescent silver clusters via cation-coupled electron-transfer in a redox-active porous ionic crystal based on dodecamolybdophosphate
Authors: Uchida Sayaka , Okunaga Tomoki , Harada Yuki , Magira Shotaro , Noda Yasuto , Mizuno Takashi , Tachikawa Takashi
Published: February 2019

Rapid formation of small mixed-valence luminescent silver clusters via cation-coupled electron-transfer by redox-active polyoxometalate-based porous crystals is reported.
Dynamic magnetic characterization and magnetic particle imaging enhancement of magnetic-gold core–shell nanoparticles
Authors: Tomitaka Asahi , Ota Satoshi , Nishimoto Kizuku , Arami Hamed , Takemura Yasushi , Nair Madhavan
Published: February 2019

The gold coating on magnetic core nanoparticles enhanced magnetic particle imaging performance due to an alteration in dynamic magnetic responses.
Solution-phase, template-free synthesis of PbI2 and MAPbI3 nano/microtubes for high-sensitivity photodetectors
Authors: Chandrasekar Perumal Veeramalai , Yang Shengyi , Hu Jinming , Sulaman Muhammad , Shi Yuansheng , Saleem Muhammad Imran , Tang Yi , Jiang Yurong , Zou Bingsuo
Published: February 2019

Solution-phase, template-free synthesis of PbI2 and MAPbI3 nano/microtubes and their applications in high-sensitivity photodetectors are presented.
Mechanochemical synthesis of N-doped porous carbon at room temperature
Authors: Casco Mirian Elizabeth , Kirchhoff Sebastian , Leistenschneider Desirée , Rauche Marcus , Brunner Eike , Borchardt Lars
Published: February 2019

One-pot mechanochemical synthesis of N-doped porous carbons at room temperature using a planetary ball mill.
Oxygen defect-induced localized surface plasmon resonance at the WO3−x quantum dot/silver nanowire interface: SERS and photocatalysis
Authors: Wei Wei , Yao Yongji , Zhao Qi , Xu Zhilong , Wang Qinfan , Zhang Zongtao , Gao Yanfeng
Published: February 2019

Synergistic effects in a WO3−x QD@AgNW composite: the LSPR occurs at the WO3−x QD/Ag NW interface, leading to the generation of SERS and photocatalysis simultaneously.
Aggregation behavior of cetyldimethylethylammonium bromide under the influence of bovine serum albumin in aqueous/electrolyte solutions at various temperatures and compositions: conductivity and molecular dynamics study
Authors: Ahmed Md. Farid , Molla Mohammad Robel , Saha Mousumi , Shahriar Imrul , Rahman Mohammad Saidur , Halim Mohammad A. , Rub Malik Abdul , Hoque Md. Anamul , Asiri Abdullah M.
Published: February 2019

Herein, we have investigated the interaction of bovine serum albumin with a cetyldimethylethylammonium bromide,viaa conductivity and molecular dynamics methods in the absence/presence of electrolyte solutions.
Motion sensors achieved from a conducting polymer-metal Schottky contact
Authors: Zhou Yang , Fang Jian , Wang Hongxia , Zhou Hua , Yan Guilong , Shao Hao , Zhao Yan , Lin Tong
Published: February 2019

Mechanical-to-electrical energy conversion devices show potential applications in the detection of movements.
Amorphous film of cerium doped cobalt oxide as a highly efficient electrocatalyst for oxygen evolution reaction
Authors: Xu Shichen , Lv Cuncai , He Tong , Huang Zhipeng , Zhang Chi
Published: February 2019

Ce doping induces structure and chemical state variation in CoOx, producing an electrocatalyst with superb performance in the oxygen evolution reaction.
ParA proteins of secondary genome elements cross-talk and regulate radioresistance through genome copy number reduction in Deinococcus radiodurans
Authors: Kumar Maurya Ganesh , Kota Swathi , Kumar N. Naveen , Tewari Raghvendra , Misra Hari S.
Published: February 2019

Deinococcus radiodurans, an extremely radioresistant bacterium has a multipartite genome system and ploidy. Mechanisms underlying such types of bacterial genome maintenance and its role in extraordinary radioresistance are not known in this bacterium. Chromosome I (Chr I), chromosome II (Chr II) and megaplasmid (Mp) encode its own set of genome partitioning proteins. Here, we have characterized P-loop ATPases of Chr II (ParA2) and Mp (ParA3) and their roles in the maintenance of genome copies and extraordinary radioresistance. Purified ParA2 and ParA3 showed nearly similar polymerization kinetics and interaction patterns with DNA. Electron microscopic examination of purified proteins incubated with DNA showed polymerization on nicked circular dsDNA. ParA2 and ParA3 showed both homotypic and heterotypic interactions to each other, but not with ParA1 (ParA of Chr I). Similarly, ParA2 and ParA3 interacted with ParB2 and ParB3 but not with ParB1 in vivo. ParB2 and ParB3 interaction with cis-elements located upstream to the corresponding parAB operon was found to be sequence-specific. Unlike single mutant of parA2 and parA3, their double mutant (ΔparA2ΔParA3) affected copy number of cognate genome elements and resistance to γ-radiation as well as hydrogen peroxide in this bacterium. These results suggested that ParA2 and ParA3 are DNA-binding ATPases producing higher order polymers on DNA and are functionally redundant in the maintenance of secondary genome elements in D. radiodurans. The findings also suggest the involvement of secondary genome elements such as Chr II and Mp in the extraordinary radioresistance of D. radiodurans.
miR-206 inhibits osteogenic differentiation of bone marrow mesenchymal stem cells by targetting glutaminase
Authors: Chen Ying , Yang Yu-Run , Fan Xiao-Liang , Lin Peng , Yang Huan , Chen Xing-Zuo , Xu Xiao-Dong
Published: February 2019

Osteoblast-mediated bone formation is a complex process involving various pathways and regulatory factors, including cytokines, growth factors, and hormones. Investigating the regulatory mechanisms behind osteoblast differentiation is important for bone regeneration therapy. miRNAs are known as important regulators, not only in a variety of cellular processes, but also in the pathogenesis of bone diseases. In the present study, we investigated the potential roles of miR-206 during osteoblast differentiation. We report that miR-206 expression was significantly down-regulated in human bone marrow mesenchymal stem cells (BMSCs) at days 7 and 14 during osteogenic induction. Furthermore, miR-206 overexpressing BMSCs showed attenuated alkaline phosphatase (ALP) activity, Alizarin Red staining, and osteocalcin secretion. The mRNA levels of osteogenic markers, Runx2 and Osteopontin (OPN), were significantly down-regulated in miR-206 overexpressing BMSCs. We observed that significantly increased glutamine uptake at days 7 and 14 during the osteogenic induction and inhibition of glutamine metabolism by knocking down glutaminase (GLS)-suppressed osteogenic differentiation of BMSCs. Here, we discover that miR-206 could directly bind to the 3′-UTR region of GLS mRNA, resulting in suppressed GLS expression and glutamine metabolism. Finally, restoration of GLS in miR-206 overexpressing BMSCs led to recovery of glutamine metabolism and osteogenic differentiation. In summary, these results reveal a new insight into the mechanisms of the miR-206-mediated osteogenesis through regulating glutamine metabolism. Our study may contribute to the development of therapeutic agents against bone diseases.
Microstructure changes in whiter matter relate to cognitive impairment in Wilson’s disease
Authors: Dong Ting , Yang Wen-ming , Wu Ming-cai , Zhang Juan , Huang Peng , Xu Chun-sheng , Wang An-qin , Kuang Chun-jun , Gao Zhi-ling
Published: February 2019

Purpose: Wilson’s disease (WD) is a genetic disorder of copper metabolism with pathological copper accumulation in the brain. The purpose of the present study was to evaluate the relationship between the damaged white matter and the impaired cognitive function in WD patients. Materials and methods: Thirty WD adolescents and thirty age- and sex-matched healthy controls (HC) were enrolled. All subjects had received brain MRI, including conventional and diffusion-tensor imaging (DTI) scans. The DTI parameter of fractional anisotropy (FA) was calculated by diffusion kurtosis estimator software. The t test was used to compare the differences between two groups. The correlation between cognitive function and whiter matter disorders were analyzed by linear regression. The results of FA parameter and MD parameter intergroup analysis were both corrected with False Discovery Rate (FDR) simulations by SPSS. Results: WD adolescents showed significantly lower scores of time-based prospective memory (TBPM) and verbal fluency test (VFT) compared with HC. We found significantly higher FA in the right thalamus, right lentiform nucleus, left thalamus, left lentiform nucleus, and brain stem in WD adolescents. Besides, WD adolescents exhibited significantly lower FA in right cerebellum and cingulum and left middle frontal lobe compared with controls (P<0.05). There were significantly negative correlations between FA in bilateral lentiform and thalamus and cognitive impairment in WD adolescents (P<0.05). Conclusion: The whiter matter of WD adolescents was impaired and mainly distributed in subcortical brain regions. The impaired cognitive function was affected by the damaged whiter matter. The present study may be helpful for recognition and understanding of WD.
Fructose 1,6-bisphosphatase: getting the message across
Authors: Timson David J.
Published: February 2019

Fructose 1,6-bisphosphatase (FBPase) is a key enzyme in gluconeogenesis. It is a potential drug target in the treatment of type II diabetes. The protein is also associated with a rare inherited metabolic disease and some cancer cells lack FBPase activity which promotes glycolysis facilitating the Warburg effect. Thus, there is interest in both inhibiting the enzyme (for diabetes treatment) and restoring its activity (in relevant cancers). The mammalian enzyme is tetrameric, competitively inhibited by Fructose 2,6-bisphosphate and negatively allosterically regulated by AMP. This allosteric regulation requires information transmission between the AMP binding site and the active site of the enzyme. A recent paper by Topaz et al. (Bioscience Reports (2019) 39, pii:BSR20180960) has added additional detail to our understanding of this information transmission process. Two residues in the AMP binding site (Lys112 and Tyr113) were shown to be involved in initiating the message between the two sites. This tyrosine residue has recently be shown to be important with protein’s interaction with the antidiabetic drug metformin. A variant designed to increase metal ion affinity (M248D) resulted in a five-fold increase in enzymatic activity. Interestingly alterations of two residues at the subunit interfaces (Tyr164 and Met177) resulted in increased responsiveness to AMP. Overall, these findings may have implications in the design of novel FBPase inhibitors or activators.
Histone acetylation and DNA methylation in ischemia/reperfusion injury
Authors: Tang Jinhua , Zhuang Shougang
Published: February 2019

Ischemic/reperfusion (I/R) injury causes a series of serious clinical problems associated with high morbidity and mortality in various disorders, such as acute kidney injury (AKI), myocardial infarction, ischemic stroke, circulatory arrest, and peripheral vascular disease. The pathophysiology and pathogenesis of I/R injury is complex and multifactorial. Recent studies have revealed that epigenetic regulation is critically involved in the pathogenesis of I/R-induced tissue injury. In this review, we will sum up recent advances on the modification, regulation, and implication of histone modifications and DNA methylation in I/R injury-induced organ dysfunction. Understandings of I/R-induced epigenetic alterations and regulations will aid in the development of potential therapeutics.
Macrophage migration inhibitory factor plays an essential role in ischemic preconditioning-mediated cardioprotection
Authors: Ruze Amanguli , Chen Bang-Dang , Liu Fen , Chen Xiao-Cui , Gai Min-Tao , Li Xiao-Mei , Ma Yi-Tong , Du Xiao-Jun , Yang Yi-Ning , Gao Xiao-Ming
Published: February 2019

Ischemic preconditioning (IPC) is an endogenous protection strategy against myocardial ischemia–reperfusion (I/R) injury. Macrophage migration inhibitory factor (MIF) released from the myocardium subjected to brief periods of ischemia confers cardioprotection. We hypothesized that MIF plays an essential role in IPC-induced cardioprotection. I/R was induced either ex vivo or in vivo in male wild-type (WT) and MIF knockout (MIFKO) mice with or without proceeding IPC (three cycles of 5-min ischemia and 5-min reperfusion). Indices of myocardial injury, regional inflammation and cardiac function were determined to evaluate the extent of I/R injury. Activations of the reperfusion injury salvage kinase (RISK) pathway, AMP-activated protein kinase (AMPK) and their downstream components were investigated to explore the underlying mechanisms. IPC conferred prominent protection in WT hearts evidenced by reduced infarct size (by 33–35%), myocyte apoptosis and enzymatic markers of tissue injury, ROS production, inflammatory cell infiltration and MCP1/CCR2 expression (all P<0.05). IPC also ameliorated cardiac dysfunction both ex vivo and in vivo. These protective effects were abolished in MIFKO hearts. Notably, IPC mediated further activations of RISK pathway, AMPK and the membrane translocation of GLUT4 in WT hearts. Deletion of MIF blunted these changes in response to IPC, which is the likely basis for the absence of protective effects of IPC against I/R injury. In conclusion, MIF plays a critical role in IPC-mediated cardioprotection under ischemic stress by activating RISK signaling pathway and AMPK. These results provide an insight for developing a novel therapeutic strategy that target MIF to protect ischemic hearts.
The serum biomarker chemerin promotes tumorigenesis and metastasis in oral squamous cell carcinoma
Authors: Lu Zhiyuan , Liang Jianfeng , He Qianting , Wan Quan , Hou Jinsong , Lian Keqian , Wang Anxun
Published: February 2019

Chemerin, which is encoded by retinoic acid receptor responder 2 (RARRES2), has been found to be related to malignant tumours, but its role in the development of oral squamous cell carcinoma (OSCC) is largely unexplored. In the present study, a higher serum level of chemerin was evident in patients with OSCC than in healthy individuals, and this high level of chemerin significantly decreased after tumour resection. In addition, high chemerin levels were positively associated with advanced tumour stage and lymph node metastasis. The expression levels of chemerin and Chemerin Receptor 23 (ChemR23) were positively correlated with the migration and invasion of OSCC cell lines. Recombinant chemerin (R-chemerin) enhanced the in vitro migration, invasion and proliferation of OSCC cells in a concentration-dependent manner, and short hairpin RNAs (shRNAs) targeting RARRES2 decreased chemerin expression and inhibited OSCC cell metastasis and proliferation both in vitro and in vivo. Additionally, R-chemerin activated manganese superoxide dismutase (SOD2) and increased the amount of intracellular hydrogen peroxide (H2O2), leading to a significant decrease in E-cadherin expression and dramatic increase in the expression of phosphorylated ERK1/2 (p-ERK1/2), Slug, Vimentin and N-cadherin, but shRNAs targeting RARRES2 reversed these effects. Moreover, knockdown of ChemR23 with small interfering RNAs (siRNA) significantly inhibited chemerin-induced OSCC cell migration/invasion and SOD2 activity. Our results revealed that chemerin is a novel biomarker for OSCC. Chemerin/ChemR23 promotes tumorigenesis and metastasis in OSCC and may be a new therapeutic target for OSCC.
Investigating dynamical properties of evolved Galactic open clusters
Authors: Angelo M. S. , Santos J. F. C. , Corradi W. J. B. , Maia F. F. S.
Published: February 2019

Context. The stellar content of Galactic open clusters is gradually depleted during their evolution as a result of internal relaxation and external interactions. The final residues of the long-term evolution of open clusters are called open cluster remnants. These are sparsely populated structures that can barely be distinguished from the field.

Aims. We aimed to characterise and compare the dynamical states of a set of 16 objects catalogued as remnants or remnant candidates. We employed parameters that are intimately associated with the dynamical evolution: age, limiting radius, stellar mass, and velocity dispersion. The sample also includes 7 objects that are catalogued as dynamically evolved open clusters for comparison purposes.

Methods. We used photometric data from the 2MASS catalogue, proper motions and parallaxes from theGaiaDR2 catalogue, and a decontamination algorithm that was applied to the three-dimensional astrometric space of proper motions and parallaxes (μα, μδ, ϖ) for stars in the objects’ areas. The luminosity and mass functions and total masses for most open cluster remnants are derived here for the first time. Our analysis used predictions ofN-body simulations to estimate the initial number of stars of the remnants from their dissolution timescales.

Results. The investigated open cluster remnants present masses (M) and velocity dispersions (σv) within well-defined ranges:Mbetween ∼10−40 M⊙andσvbetween ∼1−7 km s−1. Some objects in the remnant sample have a limiting radiusRlim ≲ 2 pc, which means that they are more compact than the investigated open clusters; other remnants haveRlimbetween ∼2−7 pc, which is comparable to the open clusters. We suggest that cluster NGC 2180 (previously classified as an open cluster) is entering a remnant evolutionary stage. In general, our clusters show signals of depletion of low-mass stars. This confirms their dynamically evolved states.

Conclusions. We conclude that the open cluster remnants we studied are in fact remnants of initially very populous open clusters (N0 ∼ 103−104stars). The outcome of the long-term evolution is to bring the final residues of the open clusters to dynamical states that are similar to each other, thus masking out the memory of the initial formation conditions of star clusters.
A hybrid fix-and-optimize heuristic for integrated inventory-transportation problem in a multi-region multi-facility supply chain
Authors: Tanksale Ajinkya , Jha J.K.
Published: February 2019

In this work, we study an integrated inventory-transportation problem in a supply chain consisting of region-bound warehouses located in different regions. The supply chain deals with multiple items that compete for storage space and transportation capacity with multi-modal transportation considering regional capacity constraint for each mode of transportation. The objective is to determine an optimal storage and transportation plan to satisfy the demand of all regions without shortages for known procurement plan for all items. The problem is formulated as a mixed integer programming (MIP) model for minimizing the total costs over a finite planning horizon. An MIP-based fix-and-optimize (F&O) heuristic with several decomposition schemes is proposed to solve the problem efficiently. The performance of the decomposition schemes is investigated against the structure of the sub-problems obtained. To enhance the performance, F&O is crossbred with two metaheuristics – genetic algorithm (GA) and iterated local search (ILS) separately, which lead to hybrid heuristic approach. Extensive numerical experiments are carried out to analyze the performance of the proposed solution methodology by randomly generating several problem instances built using data collected from the Indian Public Distribution System. The proposed solution approach is found to be computationally efficient and effective, and outperforming state of the art MIP solver Cplex for practical size problem instances. Also, the hybridization of F&O heuristic with GA and ILS boosts its performance although with a justified increase in the computational time.
Inventory management strategies for the Calabrian hospitals system
Authors: Guerriero Francesca , Miglionico Giovanna , Olivito Filomena
Published: February 2019

This paper addresses some inventory management problems arising in the Italian health care system. We aim at defining inventory management strategies for the hospitals located in Calabria, a Region in the South of Italy. We present some classical inventory management formulations together with the description of a new model, devised to take into account some peculiarities of the case under study. An extensive testing phase is carried out on real data. Numerical results show that the use of the presented mathematical models can be valuable in the decision making process.
Flexible Entry into 3-Arylpent-2-enedioic Acids via Heck–Matsuda Arylation of Dimethyl Glutaconate with Arenediazonium Tosylates
Authors: Dar’in Dmitry , Kantin Grigory , Bakulina Olga , Žalubovskis Raivis , Krasavin Mikhail
Published: February 2019

For the preparation of compound libraries of Michael acceptors with tunable reactivity toward nuclophilic selenocysteine residue of thioredoxin reductase, a range of 3-arylglutaconic acids were required. The existing methods at the time had limited scope or involved several steps. A hitherto undescribed protocol for direct palladium(II) acetate-catalyzed arylation of glutaconic acid dimethyl ester at position 3 has been developed with a diverse set of arenediazonium tosylates followed by hydrolysis. This generally good-yielding two-step sequence displayed a propensity to deliver E-configured coupling products while compounds mostly featured in the literature were predominantly Z-configured. The possibility for preparing a library of 4-arylpyridine-2,6(1H,3H)-diones has been exemplified.
Facile Synthesis of Hydroxy-Substituted Thiacrown Ethers via Nucleophilic Ring Opening of Epoxides
Authors: Stefaniak Monika , Romański Jarosław
Published: February 2019

The title thiacrown ethers were prepared in a one-step procedure to give a series of unique macrocycles possessing two unsubstituted hydroxy groups that can be easily functionalized. In addition, epoxides and macrocycles derived from Cookson’s birdcage diketone, were prepared. The nucleophilic ring opening of epoxides synthesis can be classified in the frame of click chemistry. Surprisingly, some of the prepared allyl substituted polyglycols as well as bis-epoxides, especially sulfur analogues, were prepared for the first time.
Gratification Phenomena in Infancy: A Report of Twenty-Nine Children
Authors: Koul Roshan , AlFutaisi Amna , Mani Renjith , Abdelrahim Rana , AlAdi Azza
Published: February 2019

Twenty-nine children with gratification phenomena seen in last 10 years (January 2008 to December 2017) were analyzed retrospectively. A proper history, eyewitness account, and video recordings of the event helped in making the diagnosis. Twenty-seven out of 29 (93%) children with gratification phenomena were females. Four patterns of gratification phenomena were seen. Three of these patterns not described before are reported. A typical gratification phenomenon was seen in 16 of 29 (55%) children. At the time of referral, 24% of these children were labeled epileptic and were on antiepileptic medication. This benign condition has to be recognized and extensive investigations should be avoided.
Device for rheometry, impedance spectroscopy, and electrochemistry on fluid electrodes
Authors: Narayanan Aditya , Mugele Frieder , Duits Michael H. G.
Published: February 2019

We describe the extension of a rheometer to enable in situ impedance spectroscopy and electrochemical cycling. Key advantages of this instrument over traditional flow-channel based methods for studying fluid electrodes are the possibilities to monitor the rheological properties during cycling as well as to control the mechanical history of the sample. We describe two electrochemical configurations of the instrument, allowing fluid electrodes to be studied as full and half-cells. To demonstrate the systems’ capabilities, we present characterizations of 4 different fluid electrode systems.
Classical solution to relativistic Burger’s equation in SdS and SAdS space-times
Authors: Huo Saisai , Wei Changhua
Published: February 2019

This paper is concerned with the classical solution to the Cauchy problem of relativistic Burger’s equation evolving on exterior Schwarzschild-(anti-)de Sitter (for convenience, we use SdS to denote Schwarzschild-de Sitter and SAdS to denote Schwarzschild-anti-de Sitter, respectively) spacetimes, which are spherically symmetric black hole solutions to the Einstein vacuum field equations with cosmological constant. We aim at giving a classification of the initial data under which the classical solution can exist globally or blow up in finite time on Schwarzschild-(anti-)de Sitter spacetimes. We also discuss clearly the effect of the cosmological constant and the universe mass to the stabilization of the fluids.
Dynamical structure factor of complex plasmas for varying wave vectors
Authors: Shahzad Aamir , Shakoori Muhammad Asif , He Mao-Gang , Yang Fang
Published: February 2019

The dynamical structure factor has been reported for three dimensional strongly coupled Yukawa liquids (SCYLs) through state-of-the-art equilibrium molecular dynamics (EMD) simulations in a microcanonical ensemble (NVE). The effects of varying wave vectors (k = 2π/L) have been computed along with different arrangements of Coulomb coupling (Γ) and the Debye screening parameter (κ) on the dynamical structure-factor S(k,ω) using EMD simulations. Our new investigations of S(k,ω) show that the amplitude of oscillation decreases and the frequency increases with increasing Γ, respectively, for the SCYLs. Our simulations show that the decreasing behavior is noted for the frequency of plasma S(k,ω) with increasing κ and system size (N). The obtained EMD results are found to be more efficient and accurate than that of various previous simulation data, and the present EMD approach gives more satisfactory results with appropriate system sizes at high values of k, for a wide range of plasma states (Γ, κ). It has been shown that the present density S(k,ω) of SCYLs fluctuates more at intermediate to high Coulomb couplings (average to lower system temperature ≡ 1/Γ) and low values of Debye screening; however, it less fluctuates at higher N and κ.
The theoretical investigation of radiation transport in a slot
Authors: Meng Guangwei , Zou Shiyang , Wang Min
Published: February 2019

Radiation transport in a slot is a kind of complex radiation hydrodynamic process. This work focuses on the radiation energy leaking (REL) processes of the slot. We analyze the radiation hydrodynamical evolution of the high-Z and low-Z plasmas near the slot first. Then, we propose a formula referred to as the “area law” to estimate the leaking radiation power through slots with different widths. Based on the area law, the REL processes in slots with different widths are related to each other. With a dimensionless parameter λ defined as the width ratio of slots, the dependence of the leaking energy per unit area scaled with λ on the time scaled with 1/λ is independent of the slot width before the slot is nearly closed. The simulation results also show that with a proper shrinking velocity of the side wall in the area law, the leaking energy per unit area obtained from the formula agrees well with the simulation results before the slot is nearly closed.