bluuebunny/crossref_metadata_2025 huggingface dataset:
The empirical antibiotic treatment of nosocomial spontaneous bacterial peritonitis: Results of a randomized, controlled clinical trial
Authors: Piano Salvatore , Fasolato Silvano , Salinas Freddy , Romano Antonietta , Tonon Marta , Morando Filippo , Cavallin Marta , Gola Elisabetta , Sticca Antonietta , Loregian Arianna , Palù Giorgio , Zanus Giacomo , Senzolo Marco , Burra Patrizia , Cillo Umberto , Angeli Paolo
Published: June 2015

Spontaneous bacterial peritonitis (SBP) is a common, life‐threatening complication of liver cirrhosis. Third‐generation cephalosporins have been considered the first‐line treatment of SBP. In 2014, a panel of experts suggested a broader spectrum antibiotic regimen for nosocomial SBP, according to the high rate of bacteria resistant to third‐generation cephalosporins found in these patients. However, a broader‐spectrum antibiotic regimen has never been compared to third‐generation cephalosporins in the treatment of nosocomial SBP. The aim of our study was to compare meropenem plus daptomycin versus ceftazidime in the treatment of nosocomial SBP. Patients with cirrhosis and nosocomial SBP were randomized to receive meropenem (1 g/8 hours) plus daptomycin (6 mg/kg/day) or ceftazidime (2 g/8 hours). A paracentesis was performed after 48 hours of treatment. A reduction in ascitic fluid neutrophil count <25% of pretreatment value was considered a treatment failure. The primary outcome was the efficacy of treatment defined by the resolution of SBP after 7 days of treatment. Thirty‐two patients were randomized and 31 were analyzed. The combination of meropenem plus daptomycin was significantly more effective than ceftazidime in the treatment of nosocomial SBP (86.7 vs. 25%; P < 0.001). Ninety‐day transplant‐free survival (TFS) was not significantly different between the two groups. In the multivariate analysis, ineffective response to first‐line treatment (hazard ratio [HR]: 20.6; P = 0.01), development of acute kidney injury during hospitalization (HR: 23.2; P = 0.01), and baseline mean arterial pressure (HR: 0.92; P = 0.01) were found to be independent predictors of 90‐day TFS. Conclusion: The combination of meropenem plus daptomycin is more effective than ceftazidime as empirical antibiotic treatment of nosocomial SBP. Efficacy of the empirical antibiotic treatment is a strong predictor of 90‐day survival in patients with nosocomial SBP. (Hepatology 2016;63:1299–1309)
Neonatal microbial colonization in mice promotes prolonged dominance of CD11b+Gr‐1+ cells and accelerated establishment of the CD4+ T cell population in the spleen
Authors: Kristensen Matilde B. , Metzdorff Stine B. , Bergström Anders , Damlund Dina S. M. , Fink Lisbeth N. , Licht Tine R. , Frøkiær Hanne
Published: June 2015

To assess the microbial influence on postnatal hematopoiesis, we examined the role of early life microbial colonization on the composition of leukocyte subsets in the neonatal spleen. A high number of CD11b+Gr‐1+ splenocytes present perinatally was sustained for a longer period in conventionally colonized (CONV) mice than in mono‐colonized (MC) and germfree (GF) mice, and the CD4+ T cell population established faster in CONV mice. At the day of birth, compared to GF mice, the expression of Cxcl2 was up‐regulated and Arg1 down‐regulated in livers of CONV mice. This coincided with lower abundance of polylobed cells in the liver of CONV mice. An earlier peak in the expression of the genes Tjp1, Cdh1, and JamA in intestinal epithelial cells of CONV mice indicated an accelerated closure of the epithelial barrier. In conclusion, we have identified an important microbiota‐dependent neonatal hematopoietic event, which we suggest impacts the subsequent development of the T cell population in the murine spleen.
Chemistry Constraints on the Origin of Life
Authors: Luisi Pier Luigi
Published: June 2015

This analysis starts from the view that prebiotic chemical evolution, leading to the first forms of life on earth, was based on a series of sequential steps, each determined by its own contingent initial conditions. This view is opposed to the more established one, which sees the origin of life as a series of preordered series of events, where each one is deterministically caused by the previous one and causally determines the next one. Some of the main constraints of chemistry that affect such prebiotic chemical evolution are examined. The notion of contingency is seen as a very important organizing process subjected to chemistry, whereby contingency also responds to a certain degree of determinism. Kinetic control, as another determinant and constraint of the prebiotic evolutionary process, can be critically important and, at a certain point of the chemical evolutionary process, kinetic control in the form of catalysis will become essential. Simple peptides can be considered as the first catalysts, at least for the condensation of peptide bonds. The concentration threshold for prebiotic reactions is often not taken into account in the literature, particularly in the field of the prebiotic RNA world. In addition, this shortcoming can make the entire prebiotic RNA world construction shaky and unreliable, including the “myth” of the perennial self‐replication of an RNA macromolecule. The general question of self‐replication and the problem of homochirality are also briefly discussed. Although these chemical constraints may hinder the reconstruction of life as it is now in the laboratory, their understanding can be useful and even essential for devising a synthetic alternative route to functional macromolecules and to their metabolic interactions.
Neopterin: An immune biomarker of coronary artery disease and its association with other CAD markers
Authors: Firoz Chelapram Kandy , Jabir Nasimudeen R. , Kamal Mohammad A. , Alama Mohammed Nabil , Damanhouri Ghazi A. , Khan Waseem , Alzahrani Anas S. , Almehdar Hussein A. , Tabrez Shams
Published: June 2015

Neopterin has been considered as an important marker of cellular inflammation. The primary objective of the current study was to determine the role of neopterin in cardiovascular disease and its association with other well known cardiac markers. The study was composed of total 200 subjects (100 confirmed coronary artery disease (CAD) patients, 50 recently diagnosed, and 50 managed CAD patients) both men and women and 100 healthy control individuals of matching age and weight. Serum neopterin analysis was done using commercial available ELISA kits. Other cardiac markers viz. troponin, creatine kinase (CK), CK MB isoenzyme (CKMB), lactate dehydrogenase (LDH), fibrinogen, C‐reactive protein (CRP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) estimation was done by standard routine biochemical methods. Neopterin level was found to be remarkably enhanced by 150% and 513% in the recently diagnosed and managed CAD patients, respectively. CK level also showed a significant rise by 62% in the managed patients. However, recently diagnosed patients did not show any significant change. Moreover, cross correlation study showed statistically significant (P < 0.01) change in neopterin and CK levels between recently and managed patients. In the other studied CAD markers such as CKMB, fibrinogen and LDH also showed a significant increase in both categories of patients. CRP level was also found to be significantly enhanced by 357% (P < 0.01) and 341% (P < 0.05) in recently diagnosed and managed patients respectively. Because of cost effectiveness, easy and quick analysis of neopterin in the serum sample, we propose neopterin as the prognostic as well as diagnostic biomarker of CAD before other markers could be tested especially in Saudi population. © 2015 IUBMB Life, 67(6):453–459, 2015
Growth Determinants Revisited Using Limited‐Information Bayesian Model Averaging
Authors: Mirestean Alin , Tsangarides Charalambos G.
Published: June 2015

We revisit the growth empirics debate using a novel limited‐information Bayesian model averaging framework in short T panels that addresses model uncertainty, dynamics, and endogeneity. We construct an estimator without restrictive distributional assumptions, illustrate its performance using simulations, and apply it to the investigation of growth determinants. Once model uncertainty, dynamics, and endogeneity are accounted for, we identify several factors that are robustly correlated with growth. We find the strongest support for the neoclassical growth variables including initial income and proxies for physical and human capital accumulation, as well as evidence in favor of both fundamental and proximate factors including macroeconomic policy, geography, and ethnic heterogeneity. In addition, we demonstrate that applying methodologies that do not account for either dynamics or endogeneity yields different sets of robust determinants. Copyright © 2015 John Wiley & Sons, Ltd.
A Surrogate Measure of Cortical Bone Matrix Density by Long T2-Suppressed MRI
Authors: Seifert Alan C , Li Cheng , Wehrli Suzanne L , Wehrli Felix W
Published: June 2015

Magnetic resonance has the potential to image and quantify two pools of water within bone: free water within the Haversian pore system (transverse relaxation time, T2> 1 ms), and water hydrogen-bonded to matrix collagen (T2 ∼ 300 to 400 μs). Although total bone water concentration quantified by MRI has been shown to scale with porosity, greater insight into bone matrix density and porosity may be gained by relaxation-based separation of bound and pore water fractions. The objective of this study was to evaluate a recently developed surrogate measurement for matrix density, single adiabatic inversion recovery (SIR) zero echo-time (ZTE) MRI, in human bone. Specimens of tibial cortical bone from 15 donors (aged 27 to 97 years; 8 female and 7 male) were examined at 9.4T field strength using two methods: (1) 1H ZTE MRI, to capture total 1H signal, and (2) 1H SIR-ZTE MRI, to selectively image matrix-associated 1H signal. Total water, bone matrix, and bone mineral densities were also quantified gravimetrically, and porosity was measured by micro-CT. ZTE apparent total water 1H concentration was 32.7 ± 3.2 M (range 28.5 to 40.3 M), and was correlated positively with porosity (R2 = 0.80) and negatively with matrix and mineral densities (R2 =  0.90 and 0.82, respectively). SIR-ZTE apparent bound water 1H concentration was 32.9 ± 3.9 M (range 24.4 to 39.8 M), and its correlations were opposite to those of apparent total water: negative with porosity (R2 = 0.73) and positive with matrix density (R2 = 0.74) and mineral density (R2 = 0.72). Porosity was strongly correlated with gravimetric matrix density (R2 = 0.91, negative) and total water density (R2 = 0.92, positive). The strong correlations of SIR-ZTE-derived apparent bound water 1H concentration with ground-truth measurements suggest that this quantitative solid-state MRI method provides a nondestructive surrogate measure of bone matrix density. © 2015 American Society for Bone and Mineral Research.
Multiparametric control for enhanced biofilm selection in microbial fuel cells
Authors: Molognoni Daniele , Puig Sebastià , Balaguer M Dolors , Capodaglio Andrea G , Callegari Arianna , Colprim Jesús
Published: June 2015

BACKGROUND

Microbial fuel cells (MFCs) directly convert the chemical energy present in wastewater into electricity. Enriching exoelectrogenic bacteria in the anode biofilm is a current and challenging research target. A multiparametric control strategy, focused on organic loading rate (OLR) and external resistance (Rext) parameters, is here proposed to enhance microbial selection in MFCs.

RESULTS

The study examines the performance of a swine manure fed MFC working at optimal electrical condition. Maximum power point tracking (MPPT) control was adopted to continuously optimize applied Rext. Subsequent OLR decreases were performed to gradually improve anodic biofilm exoelectrogenic activity. The study demonstrates that high OLRs (11.2 kg COD m−3 d−1) limit MFC electrochemical losses, and increase absolute values of organic removal rate (4.6 kg COD m−3 d−1) and current production (14.9 mA). On the other hand, low OLR adoption (0.7 kg COD m−3 d−1) results in higher organic matter removal (52%) and coulombic efficiency (higher than 70%) of the MFC.

CONCLUSION

A multiparametric control for MFCs is proposed. Combining MPPT control and low OLR results in rapid improvement of exoelectrogenic activity in MFCs biofilm. The developed strategy may be useful for future MFCs applications, in order to achieve efficient start‐up and sustainable operation. © 2015 Society of Chemical Industry
Conformational transitions induced by in vitro macromolecular crowding lead to the amyloidogenesis of buffalo heart cystatin
Authors: Sohail Aamir , Bhat Sheraz A. , Siddiqui Azad A. , Zaman Masihuz , Khan Rizwan H. , Bano Bilqees
Published: June 2015

The biological cells and extracellular matrix exhibit a highly crowded environment, called as macromolecular crowding. Crowding significantly influences protein structure and may lead to its aggregation. In the present study, buffalo heart cystatin (BHC), after purification from buffalo heart tissue, has been used as a model protein for studying effect of macromolecular crowding in the presence of high concentrations of bovine serum albumin (BSA), poly‐ethylene glycol‐1000 (PEG‐1000), and poly‐ethylene glycol‐4000 (PEG‐4000). Cystatins are thiol protease inhibitors and found to be involved in various important physiological processes. Functional inactivation of BHC was observed upon crowding, which varied as a function of concentration and molecular weight of crowding agents as well as incubation time. Structural changes of BHC at tertiary and secondary level were detected with the help of fluorescence and CD spectroscopy. CD analysis showed changes of α‐helix to β‐sheet, which could be due to aggregation. The ANS‐fluorescence study suggested the unfolding and presence of some partially folded intermediates. Increase in ThT‐fluorescence and absorption of Congo red spectra with red shift, confirmed the amyloid type aggregation of BHC in the presence of various crowding agents. Finally, electron microscopy provided the physical evidence about the formation of amyloid fibrils. Results suggested that among the various crowding agents used, amyloidogenesis of BHC was maximal in case of BSA followed by PEG‐4000 and least for PEG‐1000. The present work makes an important contribution in crowding mediated protein aggregation, which can have implications of potential interest. Copyright © 2015 John Wiley & Sons, Ltd.
Plant growth responses to biochar amendment of Mediterranean soils deficient in iron and phosphorus
Authors: Alburquerque José Antonio , Cabello Marta , Avelino Rebeca , Barrón Vidal , del Campillo María Carmen , Torrent José
Published: June 2015

This study evaluated the effect of biochar on plant growth under Fe‐ and P‐deficient soil conditions. Lupin and sorghum (sensitive to soil Fe and P deficiency, respectively) were pot‐grown on one (Fe) or two (P) soils to which either two biochars of contrasting properties (produced from olive‐tree pruning and pine wood) or Fe/P fertilizers or biochars combined with Fe/P fertilizers were added.

Without Fe addition, the olive‐tree pruning biochar increased lupin growth with results comparable to those of the sole application of the Fe fertilization, while biochars combined with the Fe fertilization did not significantly affect plant growth variables relative to the Fe treatment alone. Biochar did not correct P deficiency in the tested soils. However, the application of the pine wood biochar together with a P fertilizer to a calcareous soil increased sorghum biomass yield by 42% relative to the sole application of the P fertilizer. Biochar addition did not significantly affect root traits, suggesting its scarce influence on nutrient mobilization and uptake efficiency.

Although biochar alone did not alleviate nutrient deficiency in the studied soils due to the low Fe and P contents added in available form with the tested materials, the present results suggest that biochar can provide additional benefits combined with the use of fertilizers under nutrient‐deficient conditions; and open new options to formulate biochar‐based amendments that can play a relevant role in the context of sustainable agriculture.
Differential expression of genes in purple‐shoot tea tender leaves and mature leaves during leaf growth
Authors: Zhou Qiongqiong , Sun Weijiang , Lai Zhongxiong
Published: June 2015

Background

Tea (Camellia sinensis L.), contains high levels of secondary metabolic products with both commercial and medicinal value. At present, most cultivated tea plant have green leaves; although tea plants with purple leaves exist, their supply is inadequate. During leaf growth and maturation, the content of secondary metabolic compounds decreases, resulting in higher content in tender purple leaves (TPL), and lower content in mature green leaves (MGL). The aim of this study was to analyze the differential expression of genes in these two tissues, with a cDNA‐AFLP (amplified fragment length polymorphism) approach and biochemical analysis.

Results

Compared to MGL samples, TPL samples had higher content of anthocyanin, total polyphenols and total catechins, a higher carotenoid‐to‐chlorophyll ratio and lower content of soluble sugars (glucose, fructose and sucrose). TPL samples showed a lower photosynthetic ability, demonstrated by a lower CO2 assimilation and carbohydrate accumulation rate. Using cDNA‐AFLP with 256 primer combinations, differential transcript profiling generated 148 matched transcript‐derived fragments (TDFs). Among these TDFs, 77 genes were upregulated and 71 were downregulated. These were grouped into 11 functional categories which are important for final tea quality parameters.

Conclusions

Our data presented the first effort to elucidate the molecular basis of differential accumulation of key metabolites during tea leaf maturation. Our findings also provided a theoretical molecular explanation for the color change during leaf growth. © 2015 Society of Chemical Industry
Effect of the mechanical harvest of drupes on the quality characteristics of green fermented table olives
Authors: Martorana Alessandra , Alfonzo Antonio , Settanni Luca , Corona Onofrio , La Croce Francesco , Caruso Tiziano , Moschetti Giancarlo , Francesca Nicola
Published: June 2015

BACKGROUND

Because of damage caused by mechanical harvesting, the drupes for table olive production are traditionally hand harvested. Until now, no data have been available on the microbiological and chemical features of mechanically harvested drupes during fermentation.

RESULTS

Drupes mechanically harvested and inoculated with Lactobacillus pentosus OM13 were characterized by the lowest concentrations of potential spoilage microorganisms. On the other hand, drupes mechanically harvested and subjected to spontaneous fermentation showed the highest concentration of Enterobacteriaceae and pseudomonads during transformation. The lowest decrease of pH (4.20) was registered for the trials inoculated with the starter culture. Differences in terms of volatile organic compounds were estimated among trials. Multivariate analysis showed that the olives processed from the drupes mechanically harvested and inoculated with starter were closely related to control production (drupes manually harvested) in terms of microbiological and pH values. Sensory analysis evidenced negative evaluations only for the uninoculated trials.

CONCLUSION

Drupes mechanically harvested and subjected to a driven fermentation with Lactobacillus pentosus OM13 determined the production of table olives with appreciable organoleptic features. Thus mechanical harvesting performed using a trunk shaker equipped with an inverse umbrella and the addition of starter lactic acid bacteria represents a valuable alternative to manual harvesting for table olive production at the industrial level. © 2015 Society of Chemical Industry
Resource allocation by the marine cyanobacterium SynechococcusWH8102 in response to different nutrient supply ratios
Authors: Mouginot Céline , Zimmerman Amy E. , Bonachela Juan A. , Fredricks Helen , Allison Steven D. , Van Mooy Benjamin A. S. , Martiny Adam C.
Published: June 2015

Differences in relative availability of nitrate vs. phosphate may contribute to regional variations in plankton elemental stoichiometry. As a representative of the globally abundant marine Synechococcus, strain WH8102 was grown in 16 chemostats up to 52  d at a fixed growth rate with nitrogen–phosphorus ratios (N : Psupply) of 1–50. Initially, the phosphate and nitrate concentrations in the vessel decreased when the respective nutrient was limiting. Cell growth generally stabilized, although several chemostats had apparent oscillations in biomass. We observed extensive plasticity in the elemental content and ratios. N : Pcell matched the supply values between N : Psupply 5 and 20. The C : Pcell followed a similar trend. In contrast, the mean C : Ncell was 6.8 and did not vary as a function of supply ratios. We also observed that induction of alkaline phosphatase, the fraction of P allocated to nucleic acids, and the lipid sulfoquinovosyldiacylglycerol : phosphatidyglycerol ratio inversely correlated with P availability. Our results suggest that this extensive plasticity in the elemental content and ratios depends both on the external nutrient availability as well as past growth history. Thus, our study provides a quantitative understanding of the regulation of the elemental stoichiometry of an abundant ocean phytoplankton lineage.
Topologically protected interface mode in plasmonic waveguide arrays
Authors: Cheng Qingqing , Pan Yiming , Wang Qianjin , Li Tao , Zhu Shining
Published: June 2015

Recent realization of nontrivial topological phases in photonic systems has provided unprecedented opportunities in steering light flow in novel manners. Based on the Su–Schriffer–Heeger (SSH) model, a topologically protected optical mode was successfully demonstrated in a plasmonic waveguide array with a kinked interface that exhibits a robust nonspreading feature. However, under the same excitation conditions, another antikinked structure seemingly cannot support such a topological interface mode, which appears to be inconsistent with the SSH model. Theoretical calculations are carried out based on the coupled‐mode theory, in which the mode properties, excitation conditions, and the robustness are studied in detail. It is revealed that under the exact eigenstate excitations, both kinked and antikinked structures do support such robust topological interface modes; however, for a realistic single‐waveguide input only the kinked structure does so. It is concluded that the symmetry of interface eigenmodes plays a crucial role, and the odd eigenmode in a kinked structure offers the capacity to excite the nonspreading interface mode in the realistic excitation of a one‐waveguide input. Our finding deepens the understanding of mode excitation and propagation in coupled waveguide systems, and could open a new avenue in optical simulations and photonic designs.

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On the Homogeneity of Metallocene Ethylene–Propylene Copolymers as Investigated by Multiple Fractionation Techniques
Authors: Phiri Mohau Justice , Dimeska Anita , Pasch Harald
Published: June 2015

The chemical heterogeneity of ethylene–propylene copolymers by multiple fractionation techniques is addressed. Three metallocene copolymer samples with different ethylene contents, ranging from 30 to 50 mol% are analyzed using bulk methods to confirm their molecular heterogeneity. In a second step, the samples are fractionated by temperature rising elution fractionation (TREF) to obtain fractions at 30, 60, 90, and 130 °C. These fractions are subsequently analyzed regarding their thermal and molecular properties. Differential scanning calorimetry, crystallization analysis fractionation, and high‐temperature high performance liquid chromatography (HT‐HPLC) results reveal that the TREF fractions collected at 130 °C are mainly due to polypropylene homopolymer, which is rather unexpected considering the high ethylene contents of the bulk samples. Most importantly, HT‐HPLC reveals a remarkably high chemical heterogeneity of the fractions and thus the bulk samples. Solution13C NMR provides the comonomer contents and sequence distributions of the fractions. These indicate that the same TREF fractions from different samples have distinctively different chemical compositions.

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Shape‐Memory Polyurethane Nanocomposites with Single Layer or Bilayer Oleic Acid‐Coated Fe3O4 Nanoparticles
Authors: Zou Hua , Weder Christoph , Simon Yoan C.
Published: June 2015

The present study aimed at developing a shape‐memory material, whose shape can be changed “on demand” upon application of an external magnetic field. Shape‐memory nanocomposites were thus prepared from a commercially available thermoplastic polyurethane (PU) with a “switching temperature” of ≈40 °C and oleic acid (OA)‐coated Fe3O4 nanoparticles (NPs). Two series of PU/Fe3O4 nanocomposite films based on the shape‐memory PU and single layer or bilayer OA‐coated Fe3O4 NPs were prepared by solution mixing followed by solvent casting. The thermal, mechanical, and shape‐memory properties of the nanocomposite films were studied and compared.
Nanoscale Bumps and Dents on Nanofibers Enabling Sonication‐Responsive Wetting and Improved Moisture Collection
Authors: Birajdar Mallinath S. , Lee Jonghwi
Published: June 2015

Nanofibers have been developed as basic nanotechnology building blocks, however, unlike with conventional textiles, nanofibers have lacked the surface engineering tools. Herein, we have developed novel basic techniques used to introduce nanoscale bumps and dents on the surfaces of nanofibers. Nanoparticles were first attached uniformly onto nanofibers by electrohydrodynamic jetting, which were subsequently thermally annealed to embed the nanoparticles (bumps). The embedded nanoparticles could be further detached via ultrasonication, resulting in the formation of nano‐craters (dents). Ultrasonication could change the contact angle of nanofibers in situ from 84° to 146°. These surface nanoengineering techniques could widen the utility window of nanofibers.
Selective killing of gastric cancer cells by a small molecule targeting ROS‐mediated ER stress activation
Authors: Zou Peng , Xia Yiqun , Chen Tongke , Zhang Junru , Wang Zhe , Chen Wenbo , Chen Minxiao , Kanchana Karvannan , Yang Shulin , Liang Guang
Published: June 2015

Gastric cancer is one of the leading causes of cancer mortality in the world. Curcumin is a natural product with multiple pharmacological activities, while its clinical application has been limited by the poor chemical stability. We have previously designed a series of curcumin derivatives with high stability and anticancer potentials. The present study aims to identify the anti‐cancer effects and mechanisms of WZ26, an analog of curcumin, in gastric cancer cells. In vitro, WZ26 showed higher chemical stability and much stronger anti‐proliferative effects than curcumin, accompanied by dose‐dependent induction of cell cycle arrest and apoptosis in gastric cancer cells. Mechanistically, the novel compound WZ26 induced ROS production, resulting in the activation of JNK‐mitochondrial and ER stress apoptotic pathways. Blockage of ROS production totally reversed WZ26‐induced JNK activation, Bcl‐2/Bax decrease, ER stress activation, and final cell apoptosis in SGC‐7901 cells. WZ26 also exhibited potent anti‐tumor effects in human gastric cancer cell xenograft models. WZ26 could be considered as a potential chemotherapeutic agent for the treatment of advanced gastric cancer. In addition, this study also demonstrated that ROS production could be act as a vital candidate pathway for inducing tumor cell apoptosis by targeting mitochondrial and ER stress‐related death pathway. © 2015 Wiley Periodicals, Inc.
Pharmacophore‐Based Virtual Screening to Discover New Active Compounds for Human Choline Kinase α1
Authors: Serrán‐Aguilera Lucía , Nuti Roberto , López‐Cara Luisa C. , Mezo Miguel Á. Gallo , Macchiarulo Antonio , Entrena Antonio , Hurtado‐Guerrero Ramón
Published: June 2015

Choline kinase (CK) catalyses the transfer of the ATP γ‐phosphate to choline to generate phosphocholine and ADP in the presence of magnesium leading to the synthesis of phosphatidylcholine. Of the three isoforms of CK described in humans, only the α isoforms (HsCKα) are strongly associated with cancer and have been validated as drug targets to treat this disease. Over the years, a large number of Hemicholinium‐3 (HC‐3)‐based HsCKα biscationic inhibitors have been developed though the relevant common features important for the biological function have not been defined. Here, selecting a large number of previous HC‐3‐based inhibitors, we discover through computational studies a pharmacophore model formed by five moieties that are included in the 1‐benzyl‐4‐(N‐methylaniline)pyridinium fragment. Using a pharmacophore‐guided virtual screening, we then identified 6 molecules that showed binding affinities in the low μM range to HsCKα1. Finally, protein crystallization studies suggested that one of these molecules is bound to the choline and ATP‐binding sites. In conclusion, we have developed a pharmacophore model that not only allowed us to dissect the structural important features of the previous HC‐3 derivatives, but also enabled the identification of novel chemical tools with good ligand efficiencies to investigate the biological functions of HsCKα1.
In silico Prediction of Aqueous Solubility: a Comparative Study of Local and Global Predictive Models
Authors: Raevsky Oleg A. , Polianczyk Daniel E. , Grigorev Veniamin Yu. , Raevskaja Olga E. , Dearden John C.
Published: June 2015

32 Quantitative Structure‐Property Relationship (QSPR) models were constructed for prediction of aqueous intrinsic solubility of liquid and crystalline chemicals. Data sets contained 1022 liquid and 2615 crystalline compounds. Multiple Linear Regression (MLR), Support Vector Machine (SVM) and Random Forest (RF) methods were used to construct global models, and k‐nearest neighbour (kNN), Arithmetic Mean Property (AMP) and Local Regression Property (LoReP) were used to construct local models. A set of the best QSPR models was obtained: for liquid chemicals with RMSE (root mean square error) of prediction in the range 0.50–0.60 log unit; for crystalline chemicals 0.80–0.90 log unit. In the case of global models the large number of descriptors makes mechanistic interpretation difficult. The local models use only one or two descriptors, so that a medicinal chemist working with sets of structurally‐related chemicals can readily estimate their solubility. However, construction of stable local models requires the presence of closely related neighbours for each chemical considered. It is probable that a consensus of global and local QSPR models will be the optimal approach for construction of stable predictive QSPR models with mechanistic interpretation.
Evidence for End‐stage Cannibalism on Sir John Franklin's Last Expedition to the Arctic, 1845
Authors: Mays S. , Beattie O.
Published: June 2015

The 1845 British naval expedition commanded by Sir John Franklin to map the Northwest Passage ended in disaster, with none returning alive from the Canadian Arctic. The 19th century Inuit testimony described cannibalism among Franklin's men in the final throes of the expedition. Such claims were controversial at the time, but were supported in the 1980s and 1990s when knife marks were identified on human remains recovered from expedition sites on King William Island. Survival cannibalism generally follows a sequence in which meat is initially cut from an intact corpse, but if further calories are required, successively greater effort is put into corpse processing. End‐stage cannibalism is characterised by breakage and boiling of bones to extract marrow fat from medullary cavities and cancellous bone. The current work involves re‐examination, using macroscopic and microscopic study, of human remains (representing a minimum of 35 bones) from the Franklin expedition. It describes evidence for breakage and polishing of broken edges of parts of some long bones. These alterations are tentatively interpreted as breakage and heating of bones in water, to facilitate marrow extraction. If this is correct, then it constitutes the first osteological evidence of end‐stage cannibalism among members of the expedition. Comparison of these osteological findings with 19th century Inuit reports provides further evidence supporting the veracity of Inuit descriptions of cannibalistic practices by expedition members. Copyright © 2015 John Wiley & Sons, Ltd.
Synthetic preparations, thermal properties and crystallization characterization of PLLA‐PPG block copolymers/clay nanocomposites
Authors: Yang Yu‐Chieh , Ho Czung‐Yu , Wu Po‐Tsun , Lee Jiunn‐Yih , Liu Hsin‐Jiant
Published: June 2015

In this study, intercalation of the polymer or pre‐polymer from solution was used to blend different proportions of polylactic acid‐propylene glycol (LPG) copolymers (polypropylene glycols (PPG) of
: 700, 1000, 2000) and lipophilic montmorillonite (clay) in order to investigate the melting and the crystalline nature of LPG copolymers/clay nanocomposites via a differential scanning calorimeter (DSC). In addition, changes in the intermolecular force and crystal morphology of the nanocomposites under different crystallization conditions were also studied. For the results, it was observed from a thermogravimetric analyzer that increasing the clay content elevated the weight loss temperature. In non‐isothermal experiments using a DSC, it was discovered that the melting temperature and crystallization temperature of the LPG copolymers also increased with increasing amounts of added clay. The crystallinity of LPG2000 + 1.5 wt% clay was enhanced by 17.00%; in addition, it was found in the crystallinity study that adding clay slowed down the crystallization rate of the LPG copolymers. Moreover, it was found via X‐ray diffractometer (XRD) that the intensity of the diffraction peaks of the 1.5 wt% specimen was stronger than that of the 0.5 wt% specimens. The results imply that copolymers with a longer chain length provide greater space for the crystals to grow, thus making it easier for larger crystals to grow. Conversely, the added clay generates an inhibitory effect in copolymers, reducing the d‐spacing (d) in the XRD. Therefore, adding clay would change the crystallization behavior and the morphology of the LPG copolymers. Copyright © 2015 John Wiley & Sons, Ltd.
Global perspectives on clinical adoption of NIPT
Authors: Minear Mollie A. , Lewis Celine , Pradhan Subarna , Chandrasekharan Subhashini
Published: June 2015

Objective

The goals of this study were to assess global trends in clinical implementation of noninvasive prenatal testing (NIPT), as commercial tests are marketed increasingly worldwide, and to identify potential challenges for current or future use.

Methods

We surveyed clinicians from 46 countries about the availability of NIPT, their experiences with using NIPT, and their views on clinical, ethical, and legal issues affecting implementation in their countries.

Results

Forty‐nine respondents from 28 countries completed the survey. The majority reported that NIPT is available in their country (n = 43) and that they offer NIPT in their current practice (n = 38). Eighteen respondents from 14 countries reported that there are plans to introduce NIPT into routine prenatal care in their country. Test prices varied widely, ranging from $350 to $2900, and several respondents observed that high test prices limited or restricted widespread use of NIPT. Responses varied both across and within countries regarding who is offered NIPT and what the overall screening protocol should be.

Conclusion

This study provides a snapshot of current use and experiences with NIPT globally. It also highlights differences in service provision that exists both across and within countries, emphasizing the need for developing national and international implementation guidelines for NIPT. © 2015 John Wiley & Sons, Ltd.
Versatile soluble oligomeric styrene supports for peptide synthesis
Authors: Erapalapati Venkataramana , Madhavan Nandita
Published: June 2015

Soluble oligomeric styrene supports are reported here with high loading capacities of 1.5–1.6 mmol/g similar to resins used in solid phase peptide synthesis. Oligoether and alkyl chains are incorporated into the scaffold to improve the support solubility and act as spacers between the attachment sites. Amino acids have been attached to the support in 59–85% yields and 0.87–1.3 mmol/g loading. The supports have been used to synthesize tri‐ to hexapeptides in 38–64% yields using only 2 equivalents of coupling reagents, which is much lower than the amount of reagents typically used in solid phase synthesis. A modular synthetic approach is used to obtain the supports so that any efficient styrene‐based attachment site can be readily incorporated into our soluble support scaffold. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2501–2509
3D‐morphology reconstruction of nanoscale phase‐separation in polymer memory blends
Authors: Khikhlovskyi Vsevolod , van Breemen Albert J. J. M. , Michels Jasper J. , Janssen René A. J. , Gelinck Gerwin H. , Kemerink Martijn
Published: June 2015

In many organic electronic devices functionality is achieved by blending two or more materials, typically polymers or molecules, with distinctly different optical or electrical properties in a single film. The local scale morphology of such blends is vital for the device performance. Here, a simple approach to study the full 3D morphology of phase‐separated blends, taking advantage of the possibility to selectively dissolve the different components is introduced. This method is applied in combination with AFM to investigate a blend of a semiconducting and ferroelectric polymer typically used as active layer in organic ferroelectric resistive switches. It is found that the blend consists of a ferroelectric matrix with three types of embedded semiconductor domains and a thin wetting layer at the bottom electrode. Statistical analysis of the obtained images excludes the presence of a fourth type of domains. The criteria for the applicability of the presented technique are discussed. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 1231–1237
Women's beliefs about breast cancer causation in a breast cancer case–control study
Authors: Lizama Natalia , Rogers Pierra , Thomson Allyson , Slevin Terry , Fritschi Lin , Saunders Christobel , Heyworth Jane
Published: June 2015

Objective

Our study sought to ascertain women's beliefs about breast cancer risk factors and whether these beliefs differed by demographic factors and personal and family history of breast cancer.

Methods

Participants in a case–control study of breast cancer rated the effect of 37 exposures on the risk of being diagnosed with breast cancer. Chi‐square tests were undertaken to measure differences in responses between cases and controls for each exposure. Logistic regression was undertaken to ascertain whether demographic factors and personal and family history of breast cancer affected participants' ability to correctly identify known breast cancer risk factors.

Results

A total of 2742 participants completed the questionnaire, comprising 1109 cases and 1633 controls. Significant differences (p < 0.05) between cases and controls were found for 16 of the 37 exposures. Younger women and university‐educated women were more likely to correctly identify known breast cancer risk factors. Women's perceptions about the effect of alcohol consumption on breast cancer risk, particularly regarding red wine, differed from that reported in the literature.

Conclusions

Beliefs about risk factors for breast cancer may differ between cases and controls. Public health initiatives aimed at increasing awareness of breast cancer risk factors should consider that women's beliefs may differ by demographic factors and family history of breast cancer. Copyright © 2015 John Wiley & Sons, Ltd.
Goal adjustment influence on psychological well‐being following advanced breast cancer diagnosis
Authors: Lam Wendy W.  T. , Yeo Winnie , Suen Joyce , Ho Wing Ming , Tsang Janice , Soong Inda , Yau Tze Kok , Wong Ka Yan , Sze Wing Kin , Ng Alice W.  Y. , Kwong Ava , Suen Dacita , Fong Daniel , Ho Samuel , Fielding Richard
Published: June 2015

Objective

A diagnosis of advanced breast cancer (ABC) challenges a woman's ambitions. This longitudinal study explored (1) if goal adjustment disposition influenced psychological adjustment patterns among women with ABC and (2) if dispositional hope and optimism moderate effects of goal adjustment on psychological adjustment.

Methods

One hundred ninety three out of 225 women with ABC were assessed while they were awaiting/receiving initial chemotherapy, then again at 6 weeks, 3 months, 6 months, and 12 months post‐baseline. Goal disengagement, goal reengagement, optimism, hope, and psychological adjustment (anxiety, depression, and positive affect) were assessed at baseline; psychological adjustment was reassessed at each follow‐up. Latent growth curve modeling was used to examine the change of psychological adjustment and test the study objectives.

Results

High goal disengagement, low reengagement, and high optimism were associated with lower initial anxiety, while high goal disengagement and optimism predicted a slower rate of change in anxiety. High goal disengagement, reengagement, and optimism were associated with lower initial depression. High goal reengagement, optimism, and hope were associated with initial positive affect scores, while optimism predicted its rate of change. Optimism moderated the effect of goal disengagement on anxiety and depression, whereas hope moderated the effect of goal reengagement on positive affect.

Conclusion

Goal disengagement and reengagement are two relatively independent processes influencing psychological well‐being. These findings will help clinicians to tailor specific interventions to help women coping with the diagnosis of ABC. Copyright © 2015 John Wiley & Sons, Ltd.
Studies on mechanical properties of thermoelectric materials by nanoindentation
Authors: He Ran , Gahlawat Sonika , Guo Chuanfei , Chen Shuo , Dahal Tulashi , Zhang Hao , Liu Weishu , Zhang Qian , Chere Eyob , White Kenneth , Ren Zhifeng
Published: June 2015

In order to fabricate durable and efficient thermoelectric generators (TEG) for applications like automobile waste heat recovery, where thermal stress is a major concern, one needs to assess the mechanical performance of the TE materials. This work reports the hardness and elastic modulus of the moderate temperature range (200–1000 °C) TE materials, including half‐Heusler, skutterudites, bismuth telluride, silicon germanium alloys, and lead selenide, using nanoindentation and atomic force microscopy (AFM). The p‐type half‐Heusler exhibits considerably higher hardness and modulus values, and lower brittleness as compared with other materials, which may be indicative of its more robust mechanical performance.
Ternary and Multinary Compounds
Authors: Tsuboi Nozomu , Wakita Kazuki , Yamada Akira , Shirakata Sho , Wada Takahiro , Niki Shigeru , Imaizumi Mitsuru , Hara Kazuhiko , Uchitomi Naotaka
Published: June 2015

The 19th International Conference on Ternary and Multinary Compounds (ICTMC‐19) was held on 1–5 September 2014 at Toki Messe, Niigata, Japan. This conference, part of the series of conferences that began in 1973 in Bath, was held traditionally as an interdisciplinary forum for the exchange of information and experience in the exciting field of materials science of ternary and multinary compounds. It was then held in Strasbourg (1975), Edinburgh (1977), Tokyo (1980), Cagliari (1982), Caracas (1984), Snowmass (1986), Kishinev (1990), Yokohama (1993), Stuttgart (1995), Salford (1997), Hsin‐chu (2000), Paris (2002), Denver (2004), Kyoto (2006), Berlin (2008), Baku (2010), and Salzburg (2012). The conference brought together researchers for the discussion of the latest developments and achievements in the field of these complex materials.

The scientific program included two plenary talks, 20 invited talks, 13 symposium talks, 50 oral presentations, and 112 poster presentations from the following 15 countries: Japan, Taiwan, Azerbaijan, Germany, Korea, Thailand, USA, Philippines, France, Belgium, China, Mexico, Moldova, Turkey, and UK. Of the papers, 95 are included in the present proceedings volumes of physica status solidi.

The Conference covered physics, chemistry, materials science, device engineering, and the growth and theory of various ternary and multinary compounds: chalcopyrite‐type (I–III–VI2, II–IV–V2), kesterite‐type (I2–II–IV–VI4), sphalerite‐type and wurtzite‐type (III–V, II–VI, etc.), perovskite‐type, skutterudite‐type, complex‐oxides, complex‐nitrides, and so on. Three symposiums in the conference were focused on new photovoltaic materials superior to CIGS, advanced characterization of solar cells, and mulitinary materials in the next generation. The Program Committee picked up three young members as the winners of the “Best Young Scientists Award” for their excellent presentations. The winners are Galina Gurieva, Ayaka Kanai, and Tsuyoshi Maeda.

The Guest Editors wish to express their gratitude to the members of the International Advisor Committee, the Program Committee, the sponsors, the Japanese Professional Group of Multinary Compounds and Solar Cells in the Japanese Society of Applied Physics, and thank all those who have contributed to this conference for their support and advice. We are very grateful to the referees for their contributions during the editorial process.

The next anniversary conference of ICTMC‐20 will be held in Germany, chaired by Prof. Roland Scheer. We convey our best wishes to the organizers for a successful meeting. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimized emitter contacting on multicrystalline silicon thin film solar cells
Authors: Gawlik A. , Höger I. , Bergmann J. , Plentz J. , Schmidt T. , Falk F. , Andrä G.
Published: June 2015

We present an optimized contacting scheme for multicrystalline silicon thin film solar cells on glass based on epitaxially crystallized emitters with a thin Al2O3 layer and a silver back reflector. In a first step a 6.5 µm thick amorphous silicon absorber layer is crystallized by a diode laser. In a second step a thin silicon emitter layer is epitaxially crystallized by an excimer laser. The emitter is covered by an Al2O3 layer with a thickness ranging from 1.0 nm to 2.5 nm, which passivates the surface and acts as a tunnel barrier. On top of the Al2O3 layer a 90–100 nm thick silver back reflector is deposited. The Al2O3 layer was found to have an optimal thickness of 1.5 nm resulting in solar cells with back reflector that achieve a maximum open‐circuit voltage of 567 mV, a short‐circuit current density of 27.9 mA/cm2, and an efficiency of 10.9%. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)