bluuebunny/crossref_metadata_2025 huggingface dataset:
Modulating the Nucleated Self‐Assembly of Tri‐β3‐Peptides Using Cucurbit[n]urils
Authors: Satav Tushar , Korevaar Peter , de Greef Tom F. A. , Huskens Jurriaan , Jonkheijm Pascal
Published: July 2016

The modulation of the hierarchical nucleated self‐assembly of tri‐β3‐peptides has been studied. β3‐Tyrosine provided a handle to control the assembly process through host‐guest interactions with CB[7] and CB[8]. By varying the cavity size from CB[7] to CB[8] distinct phases of assembling tri‐β3‐peptides were arrested. Given the limited size of the CB[7] cavity, only one aromatic β3‐tyrosine can be simultaneously hosted and, hence, CB[7] was primarily acting as an inhibitor of self‐assembly. In strong contrast, the larger CB[8] can form a ternary complex with two aromatic amino acids and hence CB[8] was acting primarily as cross‐linker of multiple fibers and promoting the formation of larger aggregates. General insights on modulating supramolecular assembly can lead to new ways to introduce functionality in supramolecular polymers.
High‐Spin Iron(I) and Iron(0) Dinitrogen Complexes Supported by N‐Heterocyclic Carbene Ligands
Authors: Ouyang Zhenwu , Cheng Jun , Li Lingling , Bao Xiaoli , Deng Liang
Published: July 2016

The use of 1,3‐dicyclohexylimidazol‐2‐ylidene (ICy) as ligand has enabled the preparation of the high‐spin tetrahedral iron(I)‐ and iron(0)–N2 complexes, namely [(ICy)3Fe(N2)][BPh4] (1) and [(ICy)3Fe(N2)] (2), the electronic structures of which have been established by various spectroscopic characterization and DFT calculations. The frequency of the N–N stretching resonance of the iron(0)–N2 complex is the lowest among the reported terminal N2 complexes of iron, signifying the beneficial roles of strongly σ‐donating ligands in combination with the high‐spin low‐valent iron center in promoting N2‐activation. The iron(0)–N2 complex can convert reversibly to the low‐spin iron(II)‐N2 hydride complex [(ICy)2(ICy′)Fe(N2)(H)] (4).
Influence of emulsification methods and use of colloidal silicon dioxide on the microencapsulation by spray drying of turmeric oleoresin in gelatin‐starch matrices
Authors: Ferreira Sungil , Malacrida Cassia R. , Telis Vania R. N.
Published: July 2016

Microencapsulated turmeric oleoresin can present improved curcumin stability and be easily applied in hydrophilic systems. Most of the microencapsulation techniques rely on the initial emulsification of the core material in the wall biopolymers and this step affects the encapsulation efficiency and properties of the resulting microcapsules. The objective of this work was to evaluate the effects of different emulsification methods, the use of colloidal silicon dioxide and Tween 80 as additives, and the rheological behaviour of the encapsulating gelatin‐starch dispersions on the emulsion stability, encapsulation efficiency, and yield of turmeric oleoresin microcapsules produced by spray‐drying. The encapsulating matrices were prepared with varied concentrations of modified starch (from 0.22–0.317 g/g (22–31.7 wt%), dry basis) and gelatin (0–0.06 g/g (0–6 wt%), dry basis). The microstructure of the emulsions was evaluated through optical microscopy and small amplitude oscillatory shear rheology. The emulsification of turmeric oleoresin was performed by the following methods: high‐shear mixing, using a rotor‐stator homogenizer, with and without addition of Tween 80 as a surfactant; and by ultrasound homogenizer with and without the colloidal silicon dioxide (Aerosil 200). The homogenization method presented considerable influence on the emulsion stability and on the average droplet sizes in the emulsion. The concentration of gelatin directly affected the emulsion and microcapsule properties. Ultrasound homogenization and the use of colloidal silicon dioxide resulted in the highest encapsulation efficiency of turmeric oleoresin in the low total‐solid formulations.
The Prognostic Impact of New‐Onset Persistent Left Bundle Branch Block Following Transcatheter Aortic Valve Implantation: A Meta‐analysis
Authors: Ando Tomo , Takagi Hisato ,   for the ALICE (All‐Literature Investigation of Cardiovascular Evidence) Group
Published: July 2016

New‐onset persistent left bundle branch block (NOP‐LBBB) is one of the most common conduction disturbances after transcatheter aortic valve implantation (TAVI). We hypothesized that NOP‐LBBB may have a clinically negative impact after TAVI. To find out, we conducted a systematic literature search of the MEDLINE/PubMed and Embase databases. Observational studies that reported clinical outcomes of NOP‐LBBB patients after TAVI were included. The random‐effects model was used to combine odds ratios, risk ratios, or hazard ratios (HRs) with 95% confidence intervals. Adjusted HRs were utilized over unadjusted HRs or risk ratios when available. A total of 4049 patients (807 and 3242 patients with and without NOP‐LBBB, respectively) were included. Perioperative (in‐hospital or 30‐day) and midterm all‐cause mortality and midterm cardiovascular mortality were comparable between the groups. The NOP‐LBBB patients experienced a higher rate of permanent pacemaker implantation (HR: 2.09, 95% confidence interval: 1.12‐3.90, P = 0.021, I2 = 83%) during midterm follow‐up. We found that NOP‐LBBB after TAVI resulted in higher permanent pacemaker implantation but did not negatively affect the midterm prognosis. Therefore, careful observation during the follow‐up is required.
Substrate Fragmentation for the Design of M. tuberculosis CYP121 Inhibitors
Authors: Kavanagh Madeline E. , Gray Janine L. , Gilbert Sophie H. , Coyne Anthony G. , McLean Kirsty J. , Davis Holly J. , Munro Andrew W. , Abell Chris
Published: July 2016

The cyclo‐dipeptide substrates of the essential M. tuberculosis (Mtb) enzyme CYP121 were deconstructed into their component fragments and screened against the enzyme. A number of hits were identified, one of which exhibited an unexpected inhibitor‐like binding mode. The inhibitory pharmacophore was elucidated, and fragment binding affinity was rapidly improved by synthetic elaboration guided by the structures of CYP121 substrates. The resulting inhibitors have low micromolar affinity, good predicted physicochemical properties and selectivity for CYP121 over other Mtb P450s. Spectroscopic characterisation of the inhibitors′ binding mode provides insight into the effect of weak nitrogen‐donor ligands on the P450 heme, an improved understanding of factors governing CYP121–ligand recognition and speculation into the biological role of the enzyme for Mtb.
Metal Nanoparticles for Virus Detection
Authors: Park Jeong‐Eun , Kim Keunsuk , Jung Yoonjae , Kim Jae‐Ho , Nam Jwa‐Min
Published: July 2016

Viruses are small agents that can infect living creatures and cause harmful diseases. Rapid, sensitive virus detection would be beneficial for public health, and recent studies have shown that nanoparticles may have applications in virus detection. In particular, the unique properties of metal nanoparticles, originating from localized surface plasmons, allow for detection of virus through various methods. Additionally, the high surface‐to‐volume ratio and ease of surface modification of these nanoparticles provide advantages for bio‐applications. In this Focus Review, we describe currently available and recent advances in virus detection methods with metal nanoparticles. First, we outline several features of traditional virus detection methods and provide a brief explanation of metal nanoparticles. Then, we discuss solution‐based or substrate‐based virus detection according to the main operating phase of the detection elements. Finally, we evaluate the use of clinical samples for virus detection with metal nanoparticles.
Surface Charge‐Transfer Doping of Graphene Nanoflakes Containing Double‐Vacancy (5‐8‐5) and Stone–Wales (55‐77) Defects through Molecular Adsorption
Authors: Shakourian‐Fard Mehdi , Jamshidi Zahra , Kamath Ganesh
Published: July 2016

The adsorption of six electron donor–acceptor (D/A) organic molecules on various sizes of graphene nanoflakes (GNFs) containing two common defects, double‐vacancy (5‐8‐5) and Stone–Wales (55‐77), are investigated by means of ab initio DFT [M06‐2X(‐D3)/cc‐pVDZ]. Different D/A molecules adsorb on a defect graphene (DG) surface with binding energies (ΔEb) of about −12 to −28 kcal mol−1. The ΔEbvalues for adsorption of molecules on the Stone–Wales GNF surface are higher than those on the double vacancy GNF surface. Moreover, binding energies increase by about 10 % with an increase in surface size. The nature of cooperative weak interactions is analyzed based on quantum theory of atoms in molecules, noncovalent interactions plot, and natural bond order analyses, and the dominant interaction is compared for different molecules. Electron density population analysis is used to explain the n‐ and p‐type character of defect graphene nanoflakes (DGNFs) and also the change in electronic properties and reactivity parameters of DGNFs upon adsorption of different molecules and with increasing DGNF size. Results indicate that the HOMO–LUMO energy gap (Eg) of DGNFs decreases upon adsorption of molecules. However, by increasing the size of DGNFs, theEgand chemical hardness of all complexes decrease and the electrophilicity index increases. Furthermore, the values of the chemical potential of acceptor–DGNF complexes decrease with increasing size, whereas those of donor–DGNF complexes increase.
Cytomorphology, clinicopathologic, and cytogenetics correlation of myelomatous effusion of serous cavities: A retrospective review
Authors: Harbhajanka Aparna , Brickman Arlen , Park Ji‐Weon , Reddy Vijaya B , Bitterman Pincas , Gattuso Paolo
Published: July 2016

Background

Myelomatous effusions (ME) of the serous cavities are rare. Identification of the atypical plasma cells in the body fluids may be critical for prognostic considerations.

Methods

We retrospectively reviewed clinicopathologic findings of 21 serous effusion specimens from 13 cases of ME including 10 pleural, two concurrent pleural and pericardial, and one peritoneal from 1994 to 2014.

Result

All 13 patients had bone marrow biopsy‐proven plasma cell myeloma (PCM), including one plasmablastic‐variant, one anaplastic‐variant and one plasma cell leukemia. The time between the bone marrow diagnoses to serous cavity involvement ranged from 43 days to 9 years (mean 2.6 years, median 1.8 years). Monoclonal protein types showed predominant IgA subtypes (50%) including IgA‐kappa (2), IgA‐lambda (3), IgG‐kappa (2), IgG‐lambda (1) free kappa chain (1) and free lambda chain (1) and three unknown. All 13 patients died of disease (median survival 32 days). Concurrent imaging studies showed evidence of adjacent local disease. Cytology of the serous fluids revealed abundant plasma cells with varying degrees of atypia, including large cells with increased N/Cratios, coarse chromatin, and prominent nucleoli. All were CD138 positive. Of these, Cytology confirmed malignancy in 19/21(90%) cases. Five cases were positive for kappa‐light chain and eight cases for lambda‐light chain. Cytogenetics of 3/7 cases showed normal karyotype and 4/7 cases showed complex‐karyotype. The patients with kappa light‐chain had better survival compared to lambda light‐chain (p = 0.051, log rank test).

Conclusion

ME in PCM can present early in the natural history of the disease or very late. The preponderance of IgA‐myeloma and complex‐cytogenetics abnormalities is a noteworthy finding. Although there are different hypotheses regarding how ME develops in PCM, our finding supports the hypothesis that direct spread of PCM into serous cavities is a likely mechanism. Diagn. Cytopathol. 2016;44:742–747. © 2016 Wiley Periodicals, Inc.
Touch cytology smear of an inflammatory hepatocellular adenoma displaying an unusual pattern: A case report
Authors: Kanda Hiroaki , Furuta Reiko , Motoi Noriko , Suzuki Naoko , Furuta Noriyuki , Komatsu Kyoko , Sugiyama Yuko , Saiura Akio , Sugitani Masahiko , Ishikawa Yuichi
Published: July 2016

The cytological diagnosis of hepatocellular adenoma (HCA) is difficult since it is a very rare tumor and lacks characteristic cytological features. We have just reported a case of inflammatory HCA that displayed an unusual histological pattern (Clin J Gastroenterol 8:426–434, 2015). A touch cytology smear sample was obtained from the surgical specimen, and it also exhibited very unique features. A 56‐year‐old male underwent partial hepatectomy for an inflammatory HCA (diameter: 1.4 cm) in the right posterior lobe of the liver. The cytological sample displayed a characteristic two‐cell pattern. One type of cells contained thick cytoplasm, a high nucleus/cytoplasmic (N/C) ratio, and well‐defined cytoplasmic borders. The other type demonstrated small pyknotic nuclei and a lower N/C ratio. The immunohistochemical staining pattern of the histological specimen suggested that the latter cells might have been undergoing apoptosis. We report a case of inflammatory HCA with characteristic features. To diagnose this type of variant, it is important to recognize the unique pattern described in this study. Diagn. Cytopathol. 2016;44:1074–1077. © 2016 Wiley Periodicals, Inc.
Large herbivores promote habitat specialization and beta diversity of African savanna trees
Authors: Pringle Robert M. , Prior Kirsten M. , Palmer Todd M. , Young Truman P. , Goheen Jacob R.
Published: July 2016

Edaphic variation in plant community composition is widespread, yet its underlying mechanisms are rarely understood and often assumed to be physiological. In East African savannas,Acaciatree species segregate sharply across soils of differing parent material: the ant‐defended whistling thorn,A. drepanolobium(ACDR), is monodominant on cracking clay vertisols that are nutrient rich but physically stressful, whereas poorly defended species such asA. brevispica(ACBR) dominate on nutrient‐poor but otherwise less‐stressful sandy loams. Using a series of field experiments, we show that large‐mammal herbivory interacts with soil properties to maintain this pattern. In the absence of large herbivores, transplanted saplings of both species established on both soil types. Browsers strongly suppressed survival and growth ofACDRsaplings on sandy soil, where resource limitation constrained defensive investment. On clay soil,ACBRsaplings established regardless of herbivory regime, but elephants prevented recruitment to maturity, apparently because trees could not tolerate the combination of biotic and abiotic stressors. Hence, each tree species was filtered out of one habitat by browsing in conjunction with different edaphic factors and at different ontogenetic stages. Browser abundance was greater on sandy soil, where trees were less defended, consistent with predicted feedbacks between plant community assembly and herbivore distributions. By exploring two inversely related axes of soil “quality” (abiotic stress and nutrient content), our study extends the range of mechanisms by which herbivores are known to promote edaphic specialization, illustrates how the high cost of a protection mutualism can constrain the realized niche of host trees, and shows that large‐scale properties of savanna ecosystems are shaped by species interactions in cryptic ways that mimic simple abiotic determinism. These results suggest that ongoing declines in large‐herbivore populations may relax spatial heterogeneity in plant assemblages and reduce the beta diversity of communities.
Tissue‐resident and memory properties of human T‐cell and NK‐cell subsets
Authors: Lugli Enrico , Hudspeth Kelly , Roberto Alessandra , Mavilio Domenico
Published: July 2016

Efficient immune responses to invading pathogens are the result of the complex but coordinated synergy between a variety of cell types from both the innate and adaptive arms of the immune system. While adaptive and innate immune responses are highly complementary, some cells types within these two systems perform similar functions, underscoring the need for redundancy and increased flexibility. In this review, we will discuss the striking shared features of immunological memory and tissue residency recently discovered between T cells, a component of the adaptive immune system, and natural killer (NK) cells, members generally assigned to the innate compartment. Specifically, we will focus on the T‐cell and NK‐cell diversity at the single‐cell level, on the discrete function of specific subsets, and on their anatomical location. Finally, we will discuss the implication of such diversity in the generation of long‐term memory.
Experimental and Theoretical Studies on the Crystal Structure of Ternary Copper Arsenides A2Cu3As3 (A = Sr, Eu)
Authors: Zhang Rong , Pan Ming‐Yan , Zhu Min , Tao Xu‐Tang , Xia Sheng‐Qing
Published: July 2016

Two new ternary copper‐containing arsenides, Sr2Cu3As3 and Eu2Cu3As3, were synthesized through Pb‐flux reactions. In combination with theoretical calculations, the crystal structures of these compounds were determined through single‐crystal X‐ray diffraction. Both compounds crystallize in the orthorhombic space group Cmcm (no.63) with the cell parameters a = 4.2465(6)/4.1866(5) Å, b = 17.604(3)/17.486(2) Å, and c = 4.2552(6)/4.2096(5) Å for the Sr‐ and Eu‐containing compounds, respectively. Temperature‐dependent magnetic susceptibility measurements suggest that both ferromagnetic and antiferromagnetic coupling exists in the structure of Eu2Cu3As3 for the Eu 4f states. According to DFT calculations, these compounds are metallic, and the Cu 3d orbitals make significant contributions to the states around the Fermi level.
Five Disk‐Shaped {MII7} (M = Mn, Fe, Co, Cu, Zn) Clusters and One Capsule‐Like {CuII6NaI2} Cluster Assembled from the Same Schiff Base Ligand
Authors: Zhang Haifeng , Zhang Jin , Liu Rui , Li Yahong , Liu Wei , Li Wu
Published: July 2016

Six transition‐metal clusters of compositions [Mn7L6](NO3)2·2CH3OH (1), [Fe7L6](NO3)2·2CH3OH (2), [Co7L6](NO3)2·2CH3OH (3), [Cu7L6](NO3)2 (4), [Zn7L6](NO3)2·2CH3OH (5), and [Cu6Na2L6](NO3)2·4CH3OH (6) {H2L = 2‐(2‐hydroxy‐3‐methoxybenzylideneamino)phenol} have been synthesized under solvothermal conditions. The structures of 1–6 have been established based on single‐crystal X‐ray diffraction studies. Complexes 1–5 possess disk‐shaped {MII7} cores, with the central MII ion and the six peripheral MII ions being linked by six µ3‐O atoms. The six MII ions of the rim of the disk are bridged in a pairwise manner by six µ2‐O atoms. Complex 2 is a very rare example of a disk‐shaped {Fe7} cluster in which all of the Fe atoms exhibit +2 oxidation state. Furthermore, this is the first time that the five isostructural heptanuclear clusters were constructed by using an identical Schiff base ligand. The molecule of complex 6 contains a capsule‐like {Cu6Na2} core. In this core, two sodium ions reside on the two vertices of the capsule and the 12 vertices of the {Cu6O6} hexagonal prism are occupied by alternately arrayed six CuII ions and six O atoms. Photoluminescence studies suggest strong emission for 5 in the solid state at room temperature. Variable‐temperature dc magnetic susceptibility studies were carried out on polycrystalline samples of 1–4 and 6. The ac susceptibility studies were also performed with 3. Strong out‐of‐phase, χ′′, signals were observed for 3 at zero field, suggesting that 3 is a class of single molecule magnet (SMM).
Highly Luminescence Anthracene Derivatives as Promising Materials for OLED Applications
Authors: Slodek Aneta , Filapek Michal , Schab‐Balcerzak Ewa , Grucela Marzena , Kotowicz Sonia , Janeczek Henryk , Smolarek Karolina , Mackowski Sebastian , Malecki Jan Grzegorz , Jedrzejowska Agnieszka , Szafraniec‐Gorol Grazyna , Chrobok Anna , Marcol Beata , Krompiec Stanislaw , Matussek Marek
Published: July 2016

Novel symmetrical anthracene derivatives with bulky carbazolyl‐fluorene, diphenylamino‐fluorene, or carbazolyl‐carbazole units connected to the anthracene frame through an ethynyl bridge were synthesized in excellent yield by using Sonogashira cross‐coupling. The ethynyl bridge in the anthracene dyes increases π‐electron conjugation and the bulky substituents considerably attenuate intermolecular interactions. The dyes possess high thermal stability, tremendous solubility in common organic solvents, and especially high photoluminescence quantum yield (Φf) in solution in the range of 77–98 %. OLED devices were fabricated. The AFM images of thin films and blends prepared from all compounds show a uniform and flat surface, indicating excellent film‐forming properties. Devices incorporating the anthracene derivative with diphenylamino‐fluorene end‐capping groups exhibited the highest value of current density (J). All of the fabricated OLED devices emitted yellowish‐orange light under applied voltage.
Localized Electrochemistry for Studying Functional Carbon Surfaces
Authors: Lagrost Corinne , Leroux Yann , Hapiot Philippe
Published: July 2016

The large amount of research about modified surfaces has inspired the concomitant development of analytical methods for investigating the properties of the modified interfaces. Local electrochemical methods offer new possibilities both for studying the properties of the functional interface and for following their preparation after each step. In this review, these different possibilities are illustrated with different examples of SECM analysis of modified surfaces with a special emphasis on carbon materials.
Voltammetric Detection of Oxidative DNA Damage Based on Interactions between Polymeric Dyes and DNA
Authors: Kuzin Yury , Ivanov Alexey , Evtugyn Gennady , Hianik Tibor
Published: July 2016

Oxidative damage of DNA was assessed with glassy carbon electrode (GCE) coated with electropolymerized Methylene Blue (MB). For this purpose, DNA solution was first mixed with an oxidant (Fenton reagent, H2O2 alone and in the presence of Cu(II) ions) and then placed on the polymeric film surface. After washing, the cyclic voltammogram was recorded in buffer solution and the anodic peak potential measured against that before the contact with DNA. Oxidative DNA damage resulted in remarkable decrease of the anodic peak potential which depended on the oxidant nature and incubation period. Specificity of the DNA – MB interactions was confirmed by surface plasmon resonance (SPR) measurements. Similar experiment performed with polymerized Methylene Green (MG) and Neutral Red (NR) showed lower selectivity of the response toward various sources of reactive oxygen species. The protocol of the DNA damage detection was tested on the estimation of antioxidant properties of green tea extract and red table wine.
Detection of Thiols by o‐Quinone Nanocomposite Modified Electrodes
Authors: Devasurendra Amila M. , Zhu Tianxia , Kirchhoff Jon R.
Published: July 2016

A chemically modified glassy carbon (GC) electrode was developed as an amperometric sensor for detection of biological thiols. The electrode was modified by inclusion of co‐enzyme pyrroloquinoline quinone (PQQ) and a co‐catalyst of oxidized single wall carbon nanotubes (Ox‐SWNT) into a gold polypyrrole (Au‐PPy) nanocomposite matrix. The electrode (PQQ/Ox‐SWNT/Au‐PPy/GC) was characterized using scanning electron microscopy and cyclic voltammetry. Optimal conditions for the PQQ/Ox‐SWNT/Au‐PPy/GC electrode were determined and then utilized for the amperometric detection of L‐cysteine, N‐acetyl‐L‐cysteine, L‐penicillamine and D, L‐glutathione. The electrochemical response for each thiol in pH 3.2 citrate phosphate buffer at +450 mV (vs. Ag/AgCl) was found to be linear with limit of detections (LOD, S/N=3) ranging from 0.50 µM for L‐penicillamine to 1.55 µM for D, L‐glutathione with sensitivities of 30.2 nA/µM and 3.6 nA/µM respectively. The electrode design is simple and easy to construct using a minimum amount of co‐enzyme and co‐catalyst, resulting in detection methods with very good stability and improved sensitivity for thiol detection.
Metal‐organic framework MIL‐101 as sorbent based on double‐pumps controlled on‐line solid‐phase extraction coupled with high‐performance liquid chromatography for the determination of flavonoids in environmental water samples
Authors: Liu Yue , Hu Jia , Li Yan , Li Xiao‐Shuang , Wang Zhong‐Liang
Published: July 2016

A novel method with high sensitivity for the rapid determination of chrysin, apigenin and luteolin in environment water samples was developed by double‐pumps controlled on‐line solid‐phase extraction (SPE) coupled with high‐performance liquid chromatography (HPLC). In the developed technique, metal organic framework MIL‐101 was synthesized and applied as a sorbent for SPE. The as‐synthesized MIL‐101 was characterized by scanning electron microscope, X‐ray diffraction spectrometry, thermal gravimetric analysis and micropore physisorption analysis. The MIL‐101 behaved as a fast kinetics in the adsorption of chrysin, apigenin and luteolin. On‐line SPE of chrysin, apigenin and luteolin was processed by loading a sample solution at a flow rate of 1.0 mL/min for 10 min. The extracted analytes were subsequently eluted into a ZORBAX Bonus‐RP analytical column (25 cm long × 4.6 mm i.d.) for HPLC separation under isocratic condition with a mobile phase (MeOH: ACN: 0.02 M H3PO4 = 35:35:30) at a flow rate of 1.0 mL/min. Experimental conditions, including ionic strength, sample pH, sample loading rates, sample loading time and desorption analytes time, were further optimized to obtain efficient preconcentration and high‐precision determination of the analytes mentioned above. The method achieved the merits of simplicity, rapidity, sensitivity, wide linear range and high sample throughput. The possible mechanism for the adsorption of flavonoids on MIL‐101 was proposed. The developed method has been applied to determine trace chrysin, apigenin and luteolin in a variety of environmental water samples.
CZE determination of submicromolar level of phenol in seawater using improved dynamic pH junction
Authors: Yasuno Koki , Fukushi Keiichi
Published: July 2016

Using an improved dynamic pH junction as an on‐line concentration procedure, we developed CZE for determining submicromolar phenol in seawater for chloride to phenol concentration ratios of 1 000 000. To enhance the effect of conventional dynamic pH junction, a saturated fatty acid solution was injected into the capillary after sample injection. We named the procedure an improved dynamic pH junction. The method requires no sample pretreatment. The following optimum conditions were established: BGE, 40 mM sodium tetraborate decahydrate adjusted to pH 9.8 containing 0.001% m/v hexadimethrine bromide; 190 nm detection wavelength; 18 s (370 nL) vacuum injection period of sample; a saturated fatty acid solution, 30 mM sodium n‐hexanoate; 20 s (420 nL) vacuum injection period of the sodium n‐hexanoate; and 15 kV applied voltage with the sample inlet side as the cathode. The LOD for phenol was 5.9 μg/L at S/N of 3. The respective values of the RSD (intraday) of the peak area, peak height, and migration time for phenol were 1.9, 2.9, and 0.46%. The recoveries of phenol (25‒100 μg/L) spiked into the natural seawater sample obtained using the peak areas were 92‒110%. The proposed method was applied to simple biodegradation experiments using natural seawater samples containing phenol.
Online preconcentration by electrokinetic supercharging for separation of endocrine disrupting chemical and phenolic pollutants in water samples
Authors: Abdul Karim Nurul ’I. , Wan Ibrahim Wan A. , Sanagi Mohd M. , Abdul Keyon Aemi S.
Published: July 2016

Online preconcentration using electrokinetic supercharging (EKS) was proposed to enhance the sensitivity of separation for endocrine disrupting chemical (methylparaben (MP)) and phenolic pollutants (2‐nitrophenol (NP) and 4‐chlorophenol (CP)) in water sample. Important EKS and separation conditions such as the concentration of BGE; the choice of terminating electrolyte (TE); and the injection time of leading electrolyte (LE), sample, and TE were optimized. The optimum EKS‐CE conditions were as follows: BGE comprising of 12 mM sodium tetraborate pH 10.1, 100 mM sodium chloride as LE hydrodynamically injected at 50 mbar for 30 s, electrokinetic injection (EKI) of sample at –3 kV for 200 s, and 100 mM CHES as TE hydrodynamically injected at 50 mbar for 40 s. The separation was conducted at negative polarity mode and UV detection at 214 nm. Under these conditions, the sensitivity of analytes was enhanced from 100‐ to 737‐fold as compared to normal CZE with hydrodynamic injection, giving LOD of 4.89, 5.29, and 53 μg/L for MP, NP and CP, respectively. The LODs were adequate for the analysis of NP and CP in environmental water sample having concentration at or lower than their maximum admissible concentration limit (240 and 2000 μg/L for NP and CP). The LOD of MP can be suitable for the analysis of MP exists at mid‐microgram per liter level, even though the LOD was slightly higher than the concentration usually found in water samples (from ng/L to 1 μg/L). The method repeatabilities (%RSD) were in the range of 1.07–2.39% (migration time) and 8.28–14.0% (peak area).
Increase of CIK cell efficacy by upregulating cell surface MICA and inhibition of NKG2D ligand shedding in multiple myeloma
Authors: Nwangwu Chidimma A. , Weiher Hans , Schmidt‐Wolf Ingo G. H.
Published: July 2016

Multiple myeloma, which is a monoclonal plasma cell malignancy, still remains incurable despite recent progress in our understanding of this disorder. Adoptive immunotherapy of multiple myeloma using cytokine‐induced killer cells is yielding promising results in clinical trials; however, some myeloma cells still evade immune surveillance by various unknown molecular mechanisms. This study aims at increasing the efficacy of cytokine‐induced killer cells in targeting this tumor, using selective small‐molecule inhibitors which increase and stabilize surface expression of the natural killer group 2, member D ligand, major histocompatibility complex class I polypeptide‐related sequence A (MICA) on myeloma cells. We treated 2 multiple myeloma cell lines—U266 and KMS‐12‐PE—with 3 drugs. One of these drugs (sodium butyrate) is a histone deacetylase inhibitor. Another drug which was used (matrix metalloproteinase inhibitor III) blocks ligand shedding while the third drug (phenylarsine oxide) obstructs surface ligand internalization. The effect of these drugs on cell viability was determined using the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay, surface ligand expression was examined using flow cytometry, and ligand shedding was assessed using enzyme‐linked immunosorbent assay. We demonstrated that cytokine‐induced killer cells have increased cytotoxicity against multiple myeloma cells after combined drug treatment than without drug pretreatment. We also established that this increased cytotoxicity was due to potent upregulation and stabilization of surface MICA on the surface of these tumor cell lines. Our study thus highlights further therapeutic options which could be used for the treatment of multiple myeloma patients.
D‐dopachrome tautomerase is over‐expressed in pancreatic ductal adenocarcinoma and acts cooperatively with macrophage migration inhibitory factor to promote cancer growth
Authors: Guo Dawei , Guo Jinshuai , Yao Junchao , Jiang Kun , Hu Jianhua , Wang Bo , Liu Haiyang , Lin Lin , Sun Wenyu , Jiang Xiaofeng
Published: July 2016

Previous studies have established the important role of MIF in the development of pancreatic ductal adenocarcinoma (PDAC) for both therapeutic and diagnostic perspectives, but little is known about the expression and function of D‐dopachrome tautomerase (DDT), a functional homolog of MIF, in PDAC. In the present study, we demonstrated that DDT was over‐expressed in PDAC tissues in a pattern correlated with MIF. In the pancreatic cancer cell lines, PANC‐1, BXPC‐3 and ASPC‐1, both DDT and MIF were expressed and co‐localized with each other in the endosomal compartments and plasma membrane. Knockdown of DDT and MIF in PANC‐1 cells cooperatively inhibited ERK1/2 and AKT phosphorylation, increased p53 expression, and reduced cell proliferation, invasion and tumor formation. These effects were rescued by the re‐expression of MIF or DDT, but not by the forced expression of the tautomerase‐deficient mutants of DDT and MIF, P1G‐DDT and P1G‐MIF. Finally, we observed that 4‐iodo‐6‐phenylpyrimidine (4‐IPP), a covalent tautomerase inhibitor of both DDT and MIF, attenuated PANC‐1 cell proliferation and colony formation in vitro and tumor growth in vivo. Thus, targeting the tautomerase sites of both MIF and DDT may offer more efficient therapeutic benefits to PDAC patients.
High‐Valent Iron‐Oxo and ‐Nitrido Complexes: Bonding and Reactivity
Authors: Mondal Bhaskar , Roy Lisa , Neese Frank , Ye Shengfa
Published: July 2016

Multiple‐bonded iron‐oxo and ‐nitrido species have been identified or proposed as key intermediates in a range of important chemical transformations. The reported model complexes feature various coordination geometries and distinct electronic structures, and therefore exhibit diverse reactivity. The present contribution highlights the synergy from both experimental and theoretical standpoints to elucidate their different bonding situations and delineate their common mechanistic features in hydrogen‐atom abstraction processes. Our analysis reveals that a radical centered on the abstracting atom E (E=O, N), which is generated via homolysis of covalent Fe−E bonds upon approaching the transition state, is an intrinsic C−H cleaving agent. The iron‐oxo species is predicted to be more reactive than its nitride congener, in general, because the O−H bond formed in the H‐atom transfer process is often stronger than the corresponding N−H bond.
Intravital multiphoton photoconversion with a cell membrane dye
Authors: Turcotte Raphaël , Wu Juwell W. , Lin Charles P.
Published: July 2016

Photoconversion, an irreversible shift in a fluorophore emission spectrum after light exposure, is a powerful tool for marking cellular and subcellular compartments and tracking their dynamics in vivo. This paper reports on the photoconversion properties of Di‐8‐ANEPPS, a commercially available membrane dye. When illuminated with near‐infrared femtosecond laser pulses, Di‐8‐ANEPPS undergoes multiphoton photoconversion as indicated by the supralinear dependence of the conversion rate ρpc on the incident power (), and by the ability to photoconvert a thin optical section in a three‐dimensional matrix. The characteristic emission spectrum changed from red to blue, and ratiometric analysis on single cells in vitro revealed a 65‐fold increase in the blue to red wavelength ratio after photoconversion. The spectral shift is preserved in vivo for hours, making Di‐8‐ANEPPS a useful dye for intravital cell marking and tracking applications.

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Performance of heterogeneous computing with graphics processing unit and many integrated core for hartree potential calculations on a numerical grid
Authors: Choi Sunghwan , Kwon Oh‐Kyoung , Kim Jaewook , Kim Woo Youn
Published: July 2016

We investigated the performance of heterogeneous computing with graphics processing units (GPUs) and many integrated core (MIC) with 20 CPU cores (20×CPU). As a practical example toward large scale electronic structure calculations using grid‐based methods, we evaluated the Hartree potentials of silver nanoparticles with various sizes (3.1, 3.7, 4.9, 6.1, and 6.9 nm) via a direct integral method supported by the sinc basis set. The so‐called work stealing scheduler was used for efficient heterogeneous computing via the balanced dynamic distribution of workloads between all processors on a given architecture without any prior information on their individual performances. 20×CPU + 1GPU was up to ∼1.5 and ∼3.1 times faster than 1GPU and 20×CPU, respectively. 20×CPU + 2GPU was ∼4.3 times faster than 20×CPU. The performance enhancement by CPU + MIC was considerably lower than expected because of the large initialization overhead of MIC, although its theoretical performance is similar with that of CPU + GPU. © 2016 Wiley Periodicals, Inc.
Tyrosine Residues Regulate Multiple Nuclear Functions of P54nrb
Authors: Lee Ahn R. , Hung Wayne , Xie Ning , Liu Liangliang , He Leye , Dong Xuesen
Published: July 2016

The non‐POU‐domain‐containing octamer binding protein (NONO; also known as p54nrb) has various nuclear functions ranging from transcription, RNA splicing, DNA synthesis and repair. Although tyrosine phosphorylation has been proposed to account for the multi‐functional properties of p54nrb, direct evidence on p54nrb as a phosphotyrosine protein remains unclear. To investigate the tyrosine phosphorylation status of p54nrb, we performed site‐directed mutagenesis on the five tyrosine residues of p54nrb, replacing the tyrosine residues with phenylalanine or alanine, and immunoblotted for tyrosine phosphorylation. We then preceded with luciferase reporter assays, RNA splicing minigene assays, co‐immunoprecipitation, and confocal microscopy to study the function of p54nrb tyrosine residues on transcription, RNA splicing, protein–protein interaction, and cellular localization. We found that p54nrb was not phosphorylated at tyrosine residues. Rather, it has non‐specific binding affinity to anti‐phosphotyrosine antibodies. However, replacement of tyrosine with phenylalanine altered p54nrb activities in transcription co‐repression and RNA splicing in gene context‐dependent fashions by means of differential regulation of p54nrb protein association with its interacting partners and co‐regulators of transcription and splicing. These results demonstrate that tyrosine residues, regardless of phosphorylation status, are important for p54nrb function. J. Cell. Physiol. 232: 852–861, 2017. © 2016 Wiley Periodicals, Inc.
Coumestrol Inhibits Proliferation and Migration of Prostate Cancer Cells by Regulating AKT, ERK1/2, and JNK MAPK Cell Signaling Cascades
Authors: Lim Whasun , Jeong Muhah , Bazer Fuller W. , Song Gwonhwa
Published: July 2016

Coumestrol is the one of the major phytoestrogens which is abundant in soybeans, legumes, brussel sprouts, and spinach. The beneficial effects of coumestrol are well known in various biological processes including; neuroprotective effects on the nervous system, function of the female reproductive system, anti‐bacterial properties, and anti‐cancer effects. Although the anti‐tumor activity of coumestrol has been demonstrated for ovarian, breast, lung, and cervical cancers, little is known of its effects on prostate cancer. Therefore, in the present study, we investigated the chemotherapeutic effects of coumestrol on two prostate cancer cell lines, PC3 and LNCaP. Our results showed that coumestrol decreased proliferation and migration and induced apoptosis in both PC3 and LNCaP cells. Moreover, effects of coumestrol on cell signaling pathways were investigated and it increased phosphorylation of ERK1/2, JNK, P90RSK, and P53 proteins in a dose‐ and time‐dependent manner whereas phosphorylation of AKT was reduced by coumestrol under the same conditions for culture of PC3 and LNCaP cells. In addition, mitochondrial dysfunction was induced by coumestrol as evidenced by a significant loss of mitochondrial membrane potential. Furthermore, cleavage of caspase‐3 and caspase‐9, the apoptotic proteins associated with mitochondria, also changed in response to coumestrol. Coumestrol also caused mitochondrial dysfunction resulting in an increase in ROS production in PC3 and LNCaP cells. These results suggest that coumestrol can inhibit progression of prostate cancer and may be a novel chemotherapeutic agent for treatment of prostate cancer via effects mediated via the PI3K/AKT and ERK1/2 and JNK MAPK cell signaling pathways. J. Cell. Physiol. 232: 862–871, 2017. © 2016 Wiley Periodicals, Inc.
Ionic Pathways in the Photochemistry of Cyclic Sulfite Esters
Authors: White Rick C. , Arney Jr Benny E. , Perry Jacob , Thompson Nathan , Pithan Phil M. , von Gradowski Sebastian , Ihmels Heiko
Published: July 2016

The photochemistry of cyclic carbonate esters proceeds by the photochemical extrusion of carbon dioxide to give 1, 3‐diradicals which produce oxiranes as well as other radical derived species. The corresponding cyclic sulfite esters, upon irradiation, give intermediates that are trapped by alcohols yet generate no oxiranes. These results are consistent with ionic intermediates.
Synthesis of Certain New Thiazole and 1,3,4‐Thiadiazole Derivatives via the Utility of 3‐Acetylindole
Authors: Abdelhamid Abdou O. , Gomha Sobhi M. , Kandeel Saher M.
Published: July 2016

2‐(2‐(1‐(1H‐Indol‐3‐yl)ethylidene)‐hydrazinyl)‐4‐substituted 5‐(aryldiazenyl)thiazoles and 5‐((1‐(1H‐indol‐3‐yl)ethylidene)hydrazono)‐2‐substituted‐4‐phenyl‐4,5‐dihydro‐1,3,4‐thiadiazoles were synthesized via reaction of hydrazonoyl halides and 2‐(1‐(1H‐indol‐3‐yl)ethylidene)hydrazine‐1‐carbothioamide and alkyl 2‐(1‐(1H‐indol‐3‐yl)ethylidene)hydrazine‐1‐carbodithioate in ethanolic triethylamine. Structures of the newly synthesis were elucidated on the basis of elemental analysis, spectral data, and alternative synthetic route whenever possible.
Ortho‐hydroxyl effect and proton transfer via ion–neutral complex: the fragmentation study of protonated imine resveratrol analogues in mass spectrometry
Authors: Yue Lei , Li Jing , Xie Xiaodong , Guo Cheng , Yin Xinchi , Yin Qi , Chen Yinjuan , Pan Yuanjiang , Ding Chuanfan
Published: July 2016

The fragmentation pathways of protonated imine resveratrol analogues in the gas‐phase were investigated by electrospray ionization–tandem mass spectrometry. Benzyl cations were formed in the imine resveratrol analogues that had an ortho‐hydroxyl group on the benzene ring A. The specific elimination of the quinomethane neutral, CH2 = C6H4 = O, from the two isomeric ions [M1 + H]+ and [M3 + H]+ via the corresponding ion–neutral complexes was observed. The fragmentation pathway for the related meta‐isomer, ion [M2 + H]+ and the other congeners was not observed. Accurate mass measurements and additional experiments carried out with a chlorinated analogue and the trideuterated isotopolog of M1 supported the overall interpretation of the fragmentation phenomena observed. It is very helpful for understanding the intriguing roles of ortho‐hydroxyl effect and ion–neutral complexes in fragmentation reactions and enriching the knowledge of the gas‐phase chemistry of the benzyl cation. Copyright © 2016 John Wiley & Sons, Ltd.
Acute viral respiratory infections among children in MERS‐endemic Riyadh, Saudi Arabia, 2012–2013
Authors: Fagbo Shamsudeen F. , Garbati Musa A. , Hasan Rami , AlShahrani Dayel , Al‐Shehri Mohamed , AlFawaz Tariq , Hakawi Ahmed , Wani Tariq Ahmad , Skakni Leila
Published: July 2016

The emergence of the Middle East Respiratory Syndrome (MERS) in Saudi Arabia has intensified focus on Acute Respiratory Infections [ARIs]. This study sought to identify respiratory viruses (RVs) associated with ARIs in children presenting at a tertiary hospital. Children (aged ≤13) presenting with ARI between January 2012 and December 2013 tested for 15 RVs using the SeeplexRRV15 kit were retrospectively included. Epidemiological data was retrieved from patient records. Of the 2235 children tested, 61.5% were ≤1 year with a male: female ratio of 3:2. Viruses were detected in 1364 (61.02%) children, 233 (10.4%) having dual infections: these viruses include respiratory syncytial virus (RSV) (24%), human rhinovirus (hRV) (19.7%), adenovirus (5.7%), influenza virus (5.3%), and parainfluenzavirus‐3 (4.6%). Children, aged 9–11 months, were most infected (60.9%). Lower respiratory tract infections (55.4%) were significantly more than upper respiratory tract infection (45.3%) (P < 0.001). Seasonal variation of RV was directly and inversely proportional to relative humidity and temperature, respectively, for non MERS coronaviruses (NL63, 229E, and OC43). The study confirms community‐acquired RV associated with ARI in children and suggests modulating roles for abiotic factors in RV epidemiology. However, community‐based studies are needed to elucidate how these factors locally influence RV epidemiology.J. Med. Virol. 89:195–201, 2017.© 2016 Wiley Periodicals, Inc.
Effect of postharvest ethylene treatment on sugar content, glycosidase activity and its gene expression in mango fruit
Authors: Chidley Hemangi G , Deshpande Ashish B , Oak Pranjali S , Pujari Keshav H , Giri Ashok P , Gupta Vidya S
Published: July 2016

BACKGROUND

Ripening‐associated softening is one of the important attributes that largely determines the shelf‐life of mango (Mangifera indica Linn.) fruits. To reveal the effect of pre‐climacteric ethylene treatment on ripening‐related softening of Alphonso mango, ethylene treatment was given to mature, raw Alphonso fruits. Changes in the pool of reducing and non‐reducing sugars, enzymatic activity of three glycosidases: β‐d‐galactosidase, α‐d‐mannosidase and β‐d‐glucosidase and their relative transcript abundance were analysed for control and ethylene treated fruits during ripening.

RESULTS

Early activity of all the three glycosidases and accelerated accumulation of reducing and non‐reducing sugars on ethylene treatment was evident. β‐d‐Galactosidase showed the highest activity among three glycosidases in control fruits and marked increase in activity upon ethylene treatment. This was confirmed by the histochemical assay of its activity in control and ethylene treated ripe fruits. Relative transcript abundance revealed high transcript levels of β‐d‐galactosidase in control fruits. Ethylene‐treated fruits showed early and remarkable increase in the β‐d‐galactosidase transcripts while α‐d‐mannosidase transcript variants displayed early accumulation.

CONCLUSION

The findings suggest reduction in the shelf‐life of Alphonso mango upon pre‐climacteric ethylene treatment, a significant role of β‐d‐galactosidase and α‐d‐mannosidase in the ripening related softening of Alphonso fruits and transcriptional regulation of their expression by ethylene. © 2016 Society of Chemical Industry
A highly sensitive method for analyzing marker phytoplankton pigments: Ultra‐high‐performance liquid chromatography‐tandem triple quadrupole mass spectrometry
Authors: Zhang Jingjing , Liu Dongyan , Cao Peng , Wang Yujue , Keesing John K. , Li Jinhua , Chen Lingxin
Published: July 2016

A sensitive and specific ultra‐high‐performance liquid chromatography‐tandem triple quadrupole mass spectrometry (UHPLC–MS/MS) method was developed for the purpose of decreasing the detection limit of quantification (LOQ) and reducing sample analysis time. In total, 14 marker pigments were determined and validated using an internal standard (IS) method with trans‐8′‐Apo‐beta‐carotenal as the IS. Electrospray ionization in positive mode was applied for the detection of pigments. The 14 types of pigments were separated in less than 15 min and presented good linearity, with the coefficients ranging from 0.9915 to 0.9991 using a UHPLC C8 column. The LOQ attained for 14 pigments were from 0.005 ng mL−1 to 0.500 ng mL−1, which enabled quantification of the pigments in seawater at ppt level. Both intra‐day and inter‐day precisions were less than 15%. The method was validated using seawater samples and the recovery of the analytes ranged from 62.8% to 120.2% at two spiked concentrations. Compared with previous methods, UHPLC–MS/MS method improved the efficiency of qualitative analysis and significantly decreased the detection LOQ for analyzing marker phytoplankton pigments at trace/ultra‐trace levels in complex matrices.