bluuebunny/crossref_metadata_2025 huggingface dataset:
Personal Identity as a Form of Freedom
Authors: Spranzi Marta , Brunet Laurence
Published: October 2014

A commentary on “The Ethics of Anonymous Gamete Donation: Is There a Right to Know One's Genetic Origins?” by Inmaculada de Melo‐Martín, in the March‐April 2014 issue.
Disingenuous: The Latest Legal Challenges to Insurance Market Reforms
Authors: Hall Mark A.
Published: October 2014

Not since the civil rights era has enacted national legislation been fought so fiercely as the Patient Protection and Affordable Care Act. Political, ideological, and social forces have mobilized to undermine the ACA at numerous fronts, including the Supreme Court, Congress, state governments, and the court of public opinion. The ACA has survived a constitutional challenge, a presidential re‐election, numerous repeal votes in the House, and avowedly obstreperous state regulators. But it has not yet run the full gauntlet of lethal strategies. The latest line of attack is a collection of orchestrated lawsuits seeking to keep the federal exchange from paying any premium tax subsidies.

What if the challengers eventually prevail? What would happen then?
The Ethics of Translating High‐Throughput Science into Clinical Practice
Authors: Ossorio Pilar N.
Published: October 2014

Biomedical research is increasingly data intensive and computational, and “big data science” is migrating into the clinical arena. Unfortunately, ethicists, regulators, and policy‐makers have barely begun to explore the ethical, legal, and social issues raised by the variety of analytical and computational approaches in use and under development in biology and medicine. Most scholarship concerning big data bioscience has focused on privacy, a vitally important consideration but not the only one. Among the issues raised by new computational technologies are questions about safety and safety assessment, justice, and how to obtain proper informed consent. These technologies also raise a myriad of regulatory issues that could influence the probability of translating new assays or computational tools to the clinical or public health spheres.
Teaching Bioethics
Authors: Lee Lisa M. , Solomon Mildred Z. , Gutmann Amy
Published: October 2014

From accessible and affordable health care to old or new reproductive technologies, human or animal research, and beyond, the justice and well‐being of our society depends on the ability of key groups—such as scientists and health care providers—along with members of the public to identify the key issues, articulate their values and concerns, deliberate openly and respectfully, and together find the most defensible ways forward.

The Presidential Commission for the Study of Bioethical Issues and The Hastings Center are committed to improving the ethical literacy of the American public in the domain of bioethics. But what are the best educational practices to spur and support these sorts of societal conversations? And where are the greatest gaps in our collective knowledge of how best to inspire and increase moral understanding, analytical thinking in the moral domain, and professional integrity?
Genes, Race, and the Ethics of Belief
Authors: Anomaly Jonathan
Published: October 2014

A Troublesome Inheritance, by Nicholas Wade, should be read by anyone interested in race and recent human evolution. Wade deserves credit for challenging the popular dog­ma that biological differences between groups either don't exist or cannot ex­plain the relative success of different groups at different tasks. Wade's work should be read alongside another re­cent book, The 10,000 Year Explosion: How Civilization Accelerated Human Evolution, by Gregory Cochran and Henry Harpending. Together, these books represent a ma­jor turning point in the public debate about the speed with which relatively isolated groups can evolve: both books suggest that small genetic differences between members of different groups can have large impacts on their abilities and propensities, which in turn affect the outcomes of the societies in which they live.
Causes and consequences of portal vein thrombosis in 1,243 patients with cirrhosis: Results of a longitudinal study
Authors: Nery Filipe , Chevret Sylvie , Condat Bertrand , de Raucourt Emmanuelle , Boudaoud Larbi , Rautou Pierre‐Emmanuel , Plessier Aurelie , Roulot Dominique , Chaffaut Cendrine , Bourcier Valerie , Trinchet Jean‐Claude , Valla Dominique‐Charles ,   on behalf of Groupe d'Etude et de Traitement du Carcinome Hépatocellulaire
Published: October 2014

In cirrhosis, portal vein thrombosis (PVT) could be a cause or a consequence of the progression of liver disease. We analyzed data from a prospective trial of ultrasound screening for hepatocellular carcinoma in order to identify risk factors for and the impact of PVT in patients with cirrhosis. In all, 1,243 adults with cirrhosis without PVT were enrolled from 43 liver units in France and Belgium between June 2000 and March 2006. The mean follow‐up was 47 months. Doppler ultrasonography was used to check the portal vein. Progression of liver disease was defined by the development of: ascites, hepatic encephalopathy, variceal bleeding, prothrombin <45%, serum bilirubin >45 μmol/L, albumin <28 g/L, and/or creatinine >115 μmol/L. G20210A prothrombin and factor V gene mutations were assessed in sera stored at three large centers. The 5‐year cumulative incidence of PVT was 10.7%. PVT was mostly partial and varied over time. The development of PVT was independently associated with baseline esophageal varices (P = 0.01) and prothrombin time (P = 0.002), but not with disease progression before PVT, or prothrombotic mutations. Disease progression was independently associated with baseline age (hazard ratio [HR] 1.55; 95% confidence interval [CI]: 1.11‐2.17), body mass index (HR 1.40; 95% CI: 1.01‐1.95), prothrombin time (HR 0.79; 95% CI: 0.70‐0.90), serum albumin (HR 0.97; 95% CI: 0.94‐0.99), and esophageal varices (HR 1.70; 95% CI: 1.21‐2.38) but not with the prior development of PVT (HR 1.32; 95% CI: 0.68‐2.65). Conclusion: In patients with cirrhosis, the development of PVT is associated with the severity of liver disease at baseline, but does not follow a recent progression of liver disease. There is no evidence that the development of PVT is responsible for further progression of liver disease. (Hepatology 2015;61:660‐667)
Synthesis of “click” alginate hydrogel capsules and comparison of their stability, water swelling, and diffusion properties with that of Ca+2 crosslinked alginate capsules
Authors: Breger Joyce C. , Fisher Benjamin , Samy Raghu , Pollack Steven , Wang Nam Sun , Isayeva Irada
Published: October 2014

Ionically crosslinked alginate hydrogels have been extensively explored for encapsulation and immunoisolation of living cells/tissues to develop implantable cell therapies, such as islet encapsulation for bioartificial pancreas. Chemical instability of these hydrogels during long‐term implantation hinders the development of viable cell therapy. The exchange between divalent crosslinking ions (e.g., Ca+2) with monovalent ions from physiological environment causes alginate hydrogels to degrade, resulting in exposure of the donor tissue to the host's immune system and graft failure. The goal of this study was to improve stability of alginate hydrogels by utilizing covalent “click” crosslinking while preserving other biomedically viable hydrogel properties. Alginate was first functionalized to contain either pendant alkyne or azide functionalities, and subsequently reacted via “click” chemistry to form “click” gel capsules. Alginate functionalization was confirmed by NMR and gel permeation chromatography. When compared with Ca+2 capsules, “click” capsules exhibited superior stability in ionic media, while showing higher permeability to small size diffusants and similar molecular weight cut‐off and water swelling. Physicochemical properties of “click” alginate hydrogels demonstrate their potential utility for therapeutic cell encapsulation and other biomedical applications. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1120–1132, 2015.
In vivo monitoring of rat macrophages labeled with poly(l‐lysine)‐iron oxide nanoparticles
Authors: Babič Michal , Schmiedtová Martina , Poledne Rudolf , Herynek Vít , Horák Daniel
Published: October 2014

Coprecipitation of FeCl2 and FeCl3 with aqueous ammonia was used to prepare iron oxide nanoparticles dispersible in aqueous medium. Oxidation of the particles with sodium hypochlorite then yielded maghemite (γ‐Fe2O3) nanoparticles which were coated with two types of coating –d‐mannose or poly(l‐lysine) (PLL) as confirmed by FTIR analysis. The particles were <10 nm according to transmission electron microscopy. Their hydrodynamic particle size was ∼180 nm (by dynamic light scattering). The d‐mannose‐, PLL‐coated, and neat γ‐Fe2O3 particles as well as commercial Resovist® were used to label rat macrophages. The viability and contrast properties of labeled macrophages were compared. PLL‐coated γ‐Fe2O3 nanoparticles were found optimal. The labeled macrophages were injected to rats monitored in vivo by magnetic resonance imaging up to 48 h. Transport of macrophages labeled with PLL‐γ‐Fe2O3 nanoparticles in rats was confirmed. Tracking of macrophages using the developed particles can be used for monitoring of inflammations and cell migration in cell therapy. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1141–1148, 2015.
Anisotropic temperature sensitive chitosan‐based injectable hydrogels mimicking cartilage matrix
Authors: Walker Kenneth J. , Madihally Sundararajan V.
Published: October 2014

In this study, chitosan‐based hydrogels were formulated with material similarities to three of the four zones of articular cartilage. Gelatin, hyaluronic acid (HA), and β‐tricalcium phosphate for the superficial, radial, and calcified zones, were blended in different amounts and tested for formation of uniform solution, gelability, and rheological characteristics. Confined compression in two configurations (series and parallel to anisotropy), and cyclical tests were performed at the physiological conditions. In vivo gelation and systemic effects were evaluated in male BALB/c mice subcutaneous model. At day 5, hydrogels were harvested along with the adjoining skin and analyzed by histology. Formulations that produced solutions after pH adjustments were selected for each zone. Anisotropic hydrogels were formed by mixing solutions from each zone, which showed uniform gradation. Addition of HA improved structural integrity relative to other formulations. When hydrogels were in series, combined hydrogel modulus was the average of all zones while that in parallel orientation was half of that series orientation. Cyclical tests demonstrated repeatable strength and durability. All formulations were injectable into the subcutaneous region. H/E stained tissues showed minimal invasion of inflammatory cells in radial and calcified zones. Structural integrity of the hydrogel is suggested to be the resultant of the presence of HA. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 1149–1160, 2015.
Emerging Concept in DNA Methylation: Role of Transcription Factors in Shaping DNA Methylation Patterns
Authors: Marchal Claire , Miotto Benoit
Published: October 2014

DNA methylation in mammals is a key epigenetic modification essential to normal genome regulation and development. DNA methylation patterns are established during early embryonic development, and subsequently maintained during cell divisions. Yet, discrete site‐specific de novo DNA methylation or DNA demethylation events play a fundamental role in a number of physiological and pathological contexts, leading to critical changes in the transcriptional status of genes such as differentiation, tumor suppressor or imprinted genes. How the DNA methylation machinery targets specific regions of the genome during early embryogenesis and in adult tissues remains poorly understood. Here, we report advances being made in the field with a particular emphasis on the implication of transcription factors in establishing and in editing DNA methylation profiles. J. Cell. Physiol. 230: 743–751, 2015. © 2014 The Authors. Journal of Cellular Physiology published by Wiley Periodicals, Inc.
Evolution of the activated sludge process: the first 50 years
Authors: Orhon Derin
Published: October 2014

The paper presents a critical overview of the first 50 years in the evolution of the activated sludge process. Recognition of the role of aeration and microbial activity in the purification of sewage in the early studies established the basis for the accidental discovery of the process, which was immediately adapted into practice. The problems encountered during operation started a period of empirical expansion with many process modifications. As scientific support lagged behind practice, efforts were then directed towards exploring and understanding the fundamentals of the system related to substrate removal mechanisms, microbiology, process kinetics and stoichiometry, nitrogen transformations and, then, translating accumulated information into design. Extensive research generated remarkable findings which should be regarded as major milestones for future progress in many areas such as fractionation of substrate and biomass, particle size distribution, and substrate storage. A rational foundation of the activated sludge process for the removal of organic carbon could then be established based on mass balance. This approach also defined essential parameters that could relate microbial reactions involved with plant design and operation. Scientific ideas and discoveries have also enabled conceptual development of many emerging technologies such as the sequencing batch reactor, enhanced biological phosphorus removal, the oxic‐settling anaerobic process, and the super‐fast membrane bioreactor. © 2014 Society of Chemical Industry
Timing of feather molt related to date of spring migration in male white‐throated sparrows, Zonotrichia albicollis
Authors: Cristol Daniel Aaron , Johnson Karen Michelle , Jenkins Kendell Daly , Hawley Dana Michelle
Published: October 2014

In migratory birds, the ability to depart wintering grounds at the appropriate time is an important determinant of fitness. Understanding the regulation of this timing will be essential for predicting whether timing of bird migration keeps up with global climate change. We examined whether the timing of the late‐winter molt, in which white‐throated sparrows (Zonotrichia albicollis) replace head and body feathers in advance of mating, may constrain the timing of northward migratory departure. In an observational study, we found a significant correlation between timing of molt and the date on which free‐living male white‐throated sparrows disappeared from our study site during migration. The following year, we tested whether experimentally manipulating molt date by advancing photoperiod during temporary captivity would subsequently advance disappearance date once the birds were released. Sparrows that were experimentally induced to molt early disappeared from the wintering site before controls. However, the captive control birds also molted and disappeared from the site earlier than free‐living controls, suggesting that the diet during captivity had played a role. In the third winter we completed the study by advancing or delaying molt using only dietary manipulation. Together, these results show that the ability to molt early in spring is related to early disappearance from the wintering site. Early molt likely has carry‐over effects on reproduction and the requirements of molt may prevent populations from adjusting migration timing in response to global climate change. J. Exp. Zool. 321A: 586–594, 2014. © 2014 Wiley Periodicals, Inc.
Synthesis, Dissociation Constants, and Some Pharmacological Properties of Schiff Base Hydrazones and their Cyclization to 1,3‐Thiazolidin‐4‐one Derivatives
Authors: Popiołek Ł. , Chodkowska A. , Tryka A. , Pawłowski K. , Kiełczykowska M. , Kocot J. , Wujec M. , Jagiełło‐Wójtowicz E.
Published: October 2014

This study presents the synthesis, dissociation constants, and pharmacological properties of Schiff base hydrazones. The derivatives were synthesized by the condensation reaction of carboxylic acid hydrazides containing 1,2,4‐triazole system with various aldehydes. The new derivatives of 1,3‐thiazolidin‐4‐one were prepared by the cyclization reaction of Schiff base hydrazones with the mercaptoacetic acid in the presence of 1,4‐dioxane. The structure of all obtained compounds was confirmed by means of 1H NMR and 13C NMR spectra. The dissociation constants were determined using spectrophotometric method. The effects of four synthesized Schiff base hydrazones 6, 7, 11 and 12 on the central nervous system of mice in behavioral tests were examined.
Pediatric hospitalist comanagement of surgical patients: Structural, quality, and financial considerations
Authors: Rappaport David I. , Rosenberg Rebecca E. , Shaughnessy Erin E. , Schaffzin Joshua K. , O'Connor Katherine M. , Melwani Anjna , McLeod Lisa M.
Published: October 2014

Comanagement of surgical patients is occurring more commonly among adult and pediatric patients. These systems of care can vary according to institution type, comanagement structure, and type of patient. Comanagement can impact quality, safety, and costs of care. We review these implications for pediatric surgical patients. Journal of Hospital Medicine 2014;9:737–742. © 2014 Society of Hospital Medicine
The Effect of General Creative Personality and Freedom of Task Choice on Adolescents' Social Creativity
Authors: Gu Chuanhua , Hu Bi Ying , Ngwira Flemmings Fishani , Jing Zhi , Zhou Zongkui
Published: October 2014

This study investigated the effect of general creative personality and freedom of task choice on the social creativity of adolescents. The results indicated, first, that senior high school students scored higher than junior high school students. Second, girls scored higher than boys on originality, fluency, flexibility, appropriateness, and utility with regard to creative social problem‐solving. Third, freedom of task choice and its interaction with creative personality had significant effects on the originality, appropriateness, utility, flexibility, and fluency of social creativity. Adolescents who completed the task voluntarily scored higher on these dimensions than adolescents who completed it reluctantly and, among the voluntary adolescents, those with high and medium creative personality scored higher than those with low creative personality, whereas no such difference was found among the reluctant adolescents. Adolescents were more likely to show social creativity, and their general creative personality was more likely to be brought into effect under the freedom of task choice condition.
Effect of grape and other berries on cardiovascular health
Authors: Wightman JoLynne D , Heuberger Roschelle A
Published: October 2014

Cardiovascular disease is a leading cause of death globally. Many cardiovascular risk factors can be modified through lifestyle modification, including dietary patterns that emphasize daily consumption of a variety of fruits and vegetables. Recent observational and clinical studies suggest that flavonoids, especially those abundant in grapes and other berries, may be associated with health benefits, particularly cardiovascular benefits. Human clinical data support cardioprotective benefits of grapes through inhibition of platelet aggregation, decreased low‐density lipoprotein (LDL) oxidation, reduction in oxidative stress and improvements in endothelial function. Emerging evidence suggests that grapes may also have a favorable effect on blood lipids, decrease inflammation and reduce blood pressure in certain populations. Studies to date have shown that berries can have a beneficial effect on reducing LDL oxidation. Limited data suggest that berries may have a favorable effect on endothelial health and blood pressure. This review summarizes the current literature on human clinical studies examining the cardioprotective benefits of grapes and berries. Collectively, these data support the recommendation to incorporate products made with grapes and other berries into a heart‐healthy diet. © 2014 Society of Chemical Industry
Preparation and evaluation of o‐phenanthroline immobilized on a hybrid silica monolith modified with ionic liquids for reversed‐phase pressurized capillary electrochromatography
Authors: Qin Wenfei , Lü Haixia , Xie Zenghong
Published: October 2014

A novel o‐phenanthroline‐immobilized ionic‐liquid‐modified hybrid monolith for capillary electrochromatography was synthesized based on chloropropyl‐silica, which was prepared by the in situ polymerization of tetramethoxysilane and 3‐chloropropyltrimethoxysilane via a sol–gel process. The morphology of the hybrid monolith was characterized by scanning electron microscopy, and relatively stable anodic electroosmotic flow was observed under a broad pH ranged from pH 3.0 to 9.0. The separation mechanism was investigated by separating four neutral molecules (toluene, dimethylformamide, formamide, and thiourea). The obtained hybrid monolith possessed an obviously reversed‐phase retention mechanism, but when the acetonitrile content in the mobile phase was >90% v/v, a weak hydrophilic mechanism was observed on the resultant o‐phenanthroline‐modified chloropropyl‐silica hybrid monolith. The reproducibility of the column was also investigated by measuring relative standard deviations of the migration time for four neutral molecules. Relative standard deviations of run to run (n = 3), day to day (n = 3), and column to column (n = 3) were in the range of 0.4–0.7, 0.9–2.1, and 1.4–3.3%, respectively. Basic separations of various polar analytes including phenols and aromatic amines were successfully achieved.
Loading characteristics and chemical stability of headgroup‐functionalized poly(ethylene glycol)‐lipid ligand tethers on polypropylene capillary‐channeled polymer fibers
Authors: Schadock‐Hewitt Abby J. , Marcus R. Kenneth
Published: October 2014

Polypropylene capillary‐channeled polymer fibers have been modified by adsorption of headgroup‐functionalized poly(ethylene glycol)‐lipids to generate a species‐specific stationary phase. In order to study ligand binding characteristics, a fluorescein‐labeled poly(ethylene glycol)‐lipid was used as a model system. Breakthrough curves and frontal analysis were employed to characterize the surface loading characteristics across a range of lipid concentrations and mobile phase flow rates. Efficient mass transfer and fluid transport yield a linear adsorption isotherm up to the maximum loading concentration of 3 mg/mL, at a linear velocity of 57.1 mm/s. Under these conditions, the dynamic binding capacity was found to be 1.52 mg/g of fiber support. Variation of the linear velocity from 8.6 to 57.1 mm/s showed only small changes in breakthrough volume. The maximum capacity of 1.8 mg/g is found under conditions of a load velocity of 34.2 mm/s and a concentration of 3 mg/mL lipid. Exposure of the lipid modified fibers to several challenge solvents reveals a chemically robust system, with only 50% acetonitrile and hexanes able to disrupt the lipid adsorption. The straightforward capillary‐channeled polymer fiber surface modification with headgroup‐functionalized lipids provides both a diverse yet practically robust ligand tethering system.
Development of a solid‐phase microextraction fiber by the chemical binding of graphene oxide on a silver‐coated stainless‐steel wire with an ionic liquid as the crosslinking agent
Authors: Sun Min , Feng Juanjuan , Bu Yanan , Duan Huimin , Wang Xiaojiao , Luo Chuannan
Published: October 2014

Graphene oxide was bonded onto a silver‐coated stainless‐steel wire using an ionic liquid as the crosslinking agent by a layer‐by‐layer strategy. The novel solid‐phase microextraction fiber was characterized by scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and Raman microscopy. A multilayer graphene oxide layer was closely coated onto the supporting substrate. The thickness of the coating was about 4 μm. Coupled with gas chromatography, the fiber was evaluated using five polycyclic aromatic hydrocarbons (fluorene, anthracene, fluoranthene, 1,2‐benzophenanthrene, and benzo(a)pyrene) as model analytes in direct‐immersion mode. The main conditions (extraction time, extraction temperature, ionic strength, and desorption time) were optimized by a factor‐by‐factor optimization. The as‐established method exhibited a wide linearity range (0.5–200 μg/L) and low limits of determination (0.05–0.10 μg/L). It was applied to analyze environmental water samples of rain and river water. Three kinds of the model analytes were quantified and the recoveries of samples spiked at 10 μg/L were in the range of 92.3–120 and 93.8–115%, respectively. The obtained results indicated the fiber was efficient for solid‐phase microextraction analysis.
One‐Pot Glovebox‐Free Synthesis, Characterization, and Self‐Assembly of Novel Amphiphilic Poly(Sarcosine‐b‐Caprolactone) Diblock Copolymers
Authors: Cui Saide , Wang Xin , Li Zhenjiang , Zhang Qiguo , Wu Wenzhuo , Liu Jingjing , Wu Hao , Chen Cheng , Guo Kai
Published: October 2014

Novel amphiphilic polypeptoid‐polyester diblock copolymers based on poly(sarcosine) (PSar) and poly(ε‐caprolactone) (PCL) are synthesized by a one‐pot glovebox‐free approach. In this method, sarcosine N‐carboxy anhydride (Sar‐NCA) is firstly polymerized in the presence of benzylamine under N2 flow, then the resulting poly(sarcosine) is used in situ as the macro­initiator for the ring‐opening polymerization (ROP) of ε‐caprolactone using tin(II) octanoate as a catalyst. The degree of poly­merization of each block is controlled by various feed ratios of monomer/initiator. The diblock copolymers with controlled molecular weight and narrow molecular weight distributions (ĐM < 1.2) are characterized by 1H NMR, 13C NMR, and size‐exclusion chromatography. The self‐assembly behavior of PSar‐b‐PCL in water is investigated by dynamic light scattering (DLS) and transmission electron microscopy. DLS results reveal that the diblock copolymers associate into nanoparticles with average hydrodynamic diameters (DH) around 100 nm in water, which may be used as drug delivery carriers.

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Recent Strategies to Develop Polysaccharide‐Based Nanomaterials for Biomedical Applications
Authors: Wen Yifen , Oh Jung Kwon
Published: October 2014

Polysaccharides are abundant in nature, renewable, nontoxic, and intrinsically biodegradable. They possess a high level of functional groups including hydroxyl, amino, and carboxylic acid groups. These functional groups can be utilized for further modification of polysaccharides with small molecules, polymers, and crosslinkers; the modified polysaccharides have been used as effective building blocks in fabricating novel biomaterials for various biomedical applications such as drug delivery carriers, cell‐encapsulating biomaterials, and tissue engineering scaffolds. This review describes recent strategies to modify polysaccharides for the development of polysaccharide‐based biomaterials; typically self‐assembled micelles, crosslinked microgels/nanogels, three‐dimensional hydrogels, and fibrous meshes. In addition, the outlook is briefly discussed on the important aspects for the current and future development of polysaccharide‐based biomaterials, particularly tumor‐targeting intracellular drug delivery nanocarriers.

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Polyfluorene Polyelectrolyte Nanoparticles: Synthesis of Innovative Stabilizers for Heterophase Polymerization
Authors: Prescher Simon , Ghasimi Saman , Höhne Patrick , Grygiel Konrad , Landfester Katharina , Zhang Kai A. I. , Yuan Jiayin
Published: October 2014

Polyfluorene‐bearing bromohexyl side chains are quaternized by 1‐vinylimidazole in order to attach dialkylimidazolium bromide ionic liquid (IL) species along the conjugated backbone. Subsequently, polyfluorene polyelectrolyte nanoparticles (NPs) of 40 nm in average size are created via radical cross‐linking of the pendant vinylimidazolium groups. Anion exchange from Br− to BF4−, PF6−, and bis(trifluoromethylsulfonyl)imide anion (TFSI−) renders NPs adjustable dispersability in various organic solvents. The hydrophobic‐conjugated backbone and the hydrophilic dialkylimidazolium bromide IL moieties depict an amphiphilic profile, which allows the NPs to be deployed as conductive stabilizer in the emulsion polymerization of styrene. The resultant latexes are fluorescent, tunable in size and can be transferred to organic solvents without forfeiting their colloidal stability.

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Comparison of centric and reverse‐centric trajectories for highly accelerated three‐dimensional saturation recovery cardiac perfusion imaging
Authors: Wang Haonan , Bangerter Neal K. , Park Daniel J. , Adluru Ganesh , Kholmovski Eugene G. , Xu Jian , DiBella Edward
Published: October 2014

Purpose

Highly undersampled three‐dimensional (3D) saturation‐recovery sequences are affected by k‐space trajectory since the magnetization does not reach steady state during the acquisition and the slab excitation profile yields different flip angles in different slices. This study compares centric and reverse‐centric 3D cardiac perfusion imaging.

Methods

An undersampled (98 phase encodes) 3D ECG‐gated saturation‐recovery sequence that alternates centric and reverse‐centric acquisitions each time frame was used to image phantoms and in vivo subjects. Flip angle variation across the slices was measured, and contrast with each trajectory was analyzed via Bloch simulation.

Results

Significant variations in flip angle were observed across slices, leading to larger signal variation across slices for the centric acquisition. In simulation, severe transient artifacts were observed when using the centric trajectory with higher flip angles, placing practical limits on the maximum flip angle used. The reverse‐centric trajectory provided less contrast, but was more robust to flip angle variations.

Conclusion

Both of the k‐space trajectories can provide reasonable image quality. The centric trajectory can have higher CNR, but is more sensitive to flip angle variation. The reverse‐centric trajectory is more robust to flip angle variation. Magn Reson Med 74:1070–1076, 2015. © 2014 Wiley Periodicals, Inc.
Electrophysiologic features of fetal ventricular aneurysms and diverticula
Authors: Peters Carli , Wacker‐Gussmann Annette , Strasburger Janette F. , Cuneo Bettina F. , Gotteiner Nina L. , Gulecyuz Mehemet , Wakai Ronald T.
Published: October 2014

Objective

Congenital ventricular wall defects are very rare and include congenital ventricular aneurysms (CVAs) and diverticula (CVDs).

Method

We report a series of five fetuses: three with CVAs and two with CVDs referred due to fetal arrhythmia. In addition to routine fetal echocardiography, fetal magnetocardiography (fMCG) was used. The literature in CVA and CVD is reviewed.

Results

Incessant premature ventricular contractions (PVC), mainly bigeminy and trigeminy were found in three fetuses with CVAs and in one with CVD, who also had ventricular couplets. The other fetus with CVD, referred because of PVCs, had only sinus tachycardia. ST elevation was noted in two. Fetal movement had a variable impact on PVCs. Postnatal evaluation demonstrated two persistent left ventricular aneurysms and one persistent right CVD; one CVD resolved at 35‐week gestation. Two neonates had incessant PVCs. Both arrhythmias resolved spontaneously while being treated with propranolol.

Conclusion

FMCG is complementary to echocardiographic imaging. In fetuses with left ventricular wall defects, additional electrophysiological diagnosis can be made by fMCG, including the complexity of ventricular ectopy, arrhythmic response to fetal movement, presence of ST‐T wave abnormalities, and atrial amplitude increases. Prenatal risk factor assessment using fMCG can additionally support post‐natal treatment and follow‐up. © 2014 John Wiley & Sons, Ltd.
Measurement of middle cerebral artery diameter as a method for assessment of brain sparing in intra‐uterine growth‐restricted discordant twins
Authors: Barzilay Eran , Haas Jigal , de Castro Hila , Yinon Yoav , Achiron Reuven , Gilboa Yinon
Published: October 2014

Objectives

Blood vessel resistance is assessed by flow velocity indexes. However, the actual resistance should be more strongly correlated with vessel diameter rather than variations in flow velocity. We aimed to determine the utility of middle cerebral artery (MCA) diameter measurement as a tool for evaluating brain sparing effect in intrauterine growth‐restricted (IUGR) discordant twins.

Methods

Ten dichorionic–diamniotic twin pairs with weight discordance were included in the study. Fetal assessment included estimated fetal weight, umbilical artery flow, MCA flow and MCA diameter. Paired statistical analysis was used to compare MCA diameter and MCA pulsatility index (PI) between the discordant twins.

Results

MCA diameter was significantly larger in the smaller twin (mean diameter 3.55 ± 0.26 vs 2.71 ± 0.22, P = 0.018, mean ratio 1.39 ± 0.14). There was no significant difference in MCA PI values within the twin pairs (mean PI 1.51 ± 0.13 vs 1.57 ± 0.07, P = 0.878, mean ratio 0.99 ± 0.11).

Conclusions

Measurement of MCA diameter can potentially be used as a tool for assessing vessel resistance. Further studies are needed to assess the feasibility and sensitivity of this method as well as the clinical significance of MCA dilatation in the presence of normal Doppler flow indexes. © 2014 John Wiley & Sons, Ltd.
Prenatal diagnosis of osteopathia striata with cranial sclerosis
Authors: Vasiljevic Alexandre , Azzi Caroline , Lacalm Audrey , Combourieu Daniele , Collardeau‐Frachon Sophie , Dijoud Frédérique , Massardier Jerôme , Van Hul Wim , Fromageoux Caroline , Guibaud Laurent , Gaucherand Pascal , Cordier Marie‐Pierre , Massoud Mona
Published: October 2014

What is already known about this topic?

Osteopathia striata with cranial sclerosis is a rare bone dysplasia, characterized by longitudinal striations of long bones and cranial sclerosis. Age at diagnosis and clinical presentation are variable, ranging from asymptomatic to neonatal lethal cases.

What does this topic add?

Prenatal diagnosis is challenging because fetal presentation is variable and mothers with OS‐CS can be misdiagnosed. We report the first prenatal case of OS‐CS with sonographic and autopsy findings and discuss the possibility of a prenatal diagnosis when the Wilms tumor on the X chromosome mutation is identified in the mother.
Managing fetuses at high risk of retinoblastoma: lesion detection on screening MRI
Authors: Staffieri Sandra E. , McGillivray George , Elder James E. , Bristowe Amber , Cole Stephen , McKenzie John D. , Fink A. Michelle
Published: October 2014

Objective

This study aimed to describe tumour identification on magnetic resonance imaging (MRI) in a 35‐week fetus with familial retinoblastoma (RB) and report the use of prenatal ultrasound (US) and MRI screening in the management of fetuses at high risk of RB.

Method

This is a retrospective review of the prenatal course and immediate postnatal findings in all children considered at high risk of RB who had prenatal imaging with both US and MRI at our institution over a 5‐year period.

Results

Five patients met the inclusion criteria. No lesions were identified on US in any patients. Fetal MRI identified bilateral posterior pole lesions in one patient at 35 weeks' gestation. Of the four remaining patients, three developed lesions by 5 weeks of age. Only one fetus was delivered early following detection of RB.

Conclusion

We present the first reported case of RB detected in a high‐risk fetus on screening MRI at 35 weeks' gestation. A protocol for screening this population using both imaging modalities is presented. © 2014 John Wiley & Sons, Ltd.
Conducting composites prepared by the reduction of silver ions with poly(p‐phenylenediamine)
Authors: Magdziarz Przemysław , Bober Patrycja , Trchová Miroslava , Morávková Zuzana , Bláha Michal , Prokeš Jan , Stejskal Jaroslav
Published: October 2014

Poly(p‐phenylenediamine) (PPDA) and also its ladder‐like analogue were prepared by oxidation of p‐phenylenediamine with ammonium peroxydisulfate in an aqueous solution of 0.4 mol L−1 hydrochloric acid and converted to PPDA bases. These were used as reductants of silver nitrate to silver nanoparticles in 1 mol L−1 methanesulfonic acid or in water at various mole ratios of silver nitrate to p‐phenylenediamine units from 0 to 1.8. The original conductivity of the PPDA, 10−12 S cm−1, increased to the order of 100 S cm−1 for the PPDA–silver composites containing 27–40 wt% (i.e. 4.5–6.6 vol%) silver. Fourier transform infrared spectra indicated a practically unchanged molecular structure of PPDA in the composites. In contrast, Raman spectroscopy showed the existence of regions with unchanged molecular structure of PPDA as well as the presence of regions containing silver particles and oxidized PPDA moieties. © 2014 Society of Chemical Industry
In vitro culture may be the major contributing factor for transgenic versus nontransgenic proteomic plant differences
Authors: Fonseca Cátia , Planchon Sébastien , Serra Tânia , Chander Subhash , Saibo Nelson J. M. , Renaut Jenny , Oliveira M. Margarida , Batista Rita
Published: October 2014

Identification of differences between genetically modified plants and their original counterparts plays a central role in risk assessment strategy. Our main goal was to better understand the relevance of transgene presence, genetic, and epigenetic changes induced by transgene insertion, and in vitro culture in putative unintended differences between a transgenic and its comparator. Thus, we have used multiplex fluorescence 2DE coupled with MS to characterize the proteome of three different rice lines (Oryza sativa L. ssp. japonica cv. Nipponbare): a control conventional line (C), an Agrobacterium‐transformed transgenic line (Ta) and a negative segregant (NSb). We observed that Ta and NSb appeared identical (with only one spot differentially abundant—fold difference ≥ 1.5), contrasting with the control (49 spots with fold difference ≥1.5, in both Ta and NSb vs. control). Given that in vitro culture was the only event in common between Ta and NSb, we hypothesize that in vitro culture stress was the most relevant condition contributing for the observed proteomic differences. MS protein identification support our hypothesis, indicating that Ta and NSb lines adjusted their metabolic pathways and altered the abundance of several stress related proteins in order to cope with in vitro culture.
Comparative network analysis via differential graphlet communities
Authors: Wong Serene W. H. , Cercone Nick , Jurisica Igor
Published: October 2014

While current protein interaction data provides a rich resource for molecular biology, it mostly lacks condition‐specific details. Abundance of mRNA data for most diseases provides potential to model condition‐specific transcriptional changes. Transcriptional data enables modeling disease mechanisms, and in turn provide potential treatments. While approaches to compare networks constructed from healthy and disease samples have been developed, they do not provide the complete comparison, evaluations are performed on very small networks, or no systematic network analyses are performed on differential network structures. We propose a novel method for efficiently exploiting network structure information in the comparison between any graphs, and validate results in non‐small cell lung cancer. We introduce the notion of differential graphlet community to detect deregulated subgraphs between any graphs such that the network structure information is exploited. The differential graphlet community approach systematically captures network structure differences between any graphs. Instead of using connectivity of each protein or each edge, we used shortest path distributions on differential graphlet communities in order to exploit network structure information on identified deregulated subgraphs. We validated the method by analyzing three non‐small cell lung cancer datasets and validated results on four independent datasets. We observed that the shortest path lengths are significantly longer for normal graphs than for tumor graphs between genes that are in differential graphlet communities, suggesting that tumor cells create "shortcuts" between biological processes that may not be present in normal conditions.
Insights into the potential function and membrane organization of the TP0435 (Tp17) lipoprotein from Treponema pallidum derived from structural and biophysical analyses
Authors: Brautigam Chad A. , Deka Ranjit K. , Liu Wei Z. , Norgard Michael V.
Published: October 2014

The sexually transmitted disease syphilis is caused by the bacterial spirochete Treponema pallidum. This microorganism is genetically intractable, accounting for the large number of putative and undercharacterized members of the pathogen's proteome. In an effort to ascribe a function(s) to the TP0435 (Tp17) lipoprotein, we engineered a soluble variant of the protein (rTP0435) and determined its crystal structure at a resolution of 2.42 Å. The structure is characterized by an eight‐stranded β‐barrel protein with a shallow “basin” at one end of the barrel and an α‐helix stacked on the opposite end. Furthermore, there is a disulfide‐linked dimer of the protein in the asymmetric unit of the crystals. Solution hydrodynamic experiments established that purified rTP0435 is monomeric, but specifically forms the disulfide‐stabilized dimer observed in the crystal structure. The data herein, when considered with previous work on TP0435, imply plausible roles for the protein in either ligand binding, treponemal membrane architecture, and/or pathogenesis.
Computational de novo design of a four‐helix bundle protein—DND_4HB
Authors: Murphy Grant S. , Sathyamoorthy Bharatwaj , Der Bryan S. , Machius Mischa C. , Pulavarti Surya V. , Szyperski Thomas , Kuhlman Brian
Published: October 2014

The de novo design of proteins is a rigorous test of our understanding of the key determinants of protein structure. The helix bundle is an interesting de novo design model system due to the diverse topologies that can be generated from a few simple α‐helices. Previously, noncomputational studies demonstrated that connecting amphipathic helices together with short loops can sometimes generate helix bundle proteins, regardless of the bundle's exact sequence. However, using such methods, the precise positions of helices and side chains cannot be predetermined. Since protein function depends on exact positioning of residues, we examined if sequence design tools in the program Rosetta could be used to design a four‐helix bundle with a predetermined structure. Helix position was specified using a folding procedure that constrained the design model to a defined topology, and iterative rounds of rotamer‐based sequence design and backbone refinement were used to identify a low energy sequence for characterization. The designed protein, DND_4HB, unfolds cooperatively (Tm >90°C) and a NMR solution structure shows that it adopts the target helical bundle topology. Helices 2, 3, and 4 agree very closely with the design model (backbone RMSD = 1.11 Å) and >90% of the core side chain χ1 and χ2 angles are correctly predicted. Helix 1 lies in the target groove against the other helices, but is displaced 3 Å along the bundle axis. This result highlights the potential of computational design to create bundles with atomic‐level precision, but also points at remaining challenges for achieving specific positioning between amphipathic helices.
Design and characterization of ebolavirus GP prehairpin intermediate mimics as drug targets
Authors: Clinton Tracy R. , Weinstock Matthew T. , Jacobsen Michael T. , Szabo‐Fresnais Nicolas , Pandya Maya J. , Whitby Frank G. , Herbert Andrew S. , Prugar Laura I. , McKinnon Rena , Hill Christopher P. , Welch Brett D. , Dye John M. , Eckert Debra M. , Kay Michael S.
Published: October 2014

Ebolaviruses are highly lethal filoviruses that cause hemorrhagic fever in humans and nonhuman primates. With no approved treatments or preventatives, the development of an anti‐ebolavirus therapy to protect against natural infections and potential weaponization is an urgent global health need. Here, we describe the design, biophysical characterization, and validation of peptide mimics of the ebolavirus N‐trimer, a highly conserved region of the GP2 fusion protein, to be used as targets to develop broad‐spectrum inhibitors of ebolavirus entry. The N‐trimer region of GP2 is 90% identical across all ebolavirus species and forms a critical part of the prehairpin intermediate that is exposed during viral entry. Specifically, we fused designed coiled coils to the N‐trimer to present it as a soluble trimeric coiled coil as it appears during membrane fusion. Circular dichroism, sedimentation equilibrium, and X‐ray crystallography analyses reveal the helical, trimeric structure of the designed N‐trimer mimic targets. Surface plasmon resonance studies validate that the N‐trimer mimic binds its native ligand, the C‐peptide region of GP2. The longest N‐trimer mimic also inhibits virus entry, thereby confirming binding of the C‐peptide region during viral entry and the presence of a vulnerable prehairpin intermediate. Using phage display as a model system, we validate the suitability of the N‐trimer mimics as drug screening targets. Finally, we describe the foundational work to use the N‐trimer mimics as targets in mirror‐image phage display, which will be used to identify D‐peptide inhibitors of ebolavirus entry.
Synthesis of nitrogen‐containing porous carbon using calcium oxide nanoparticles
Authors: Shlyakhova E. V. , Bulusheva L. G. , Kanygin M. A. , Plyusnin P. E. , Kovalenko K. A. , Senkovskiy B. V. , Okotrub A. V.
Published: October 2014

Nitrogen‐containing porous carbon has been produced by acetonitrile vapor deposition at 700 and 800 °C on the products of thermolysis of calcium tartrate doped by iron. The template was removed by dilute HCl acid treatment, and the samples obtained were comparatively studied using transmission electron microscopy, N2 adsorption measurements, thermogravimetric analysis (TGA), X‐ray photoelectron and near‐edge X‐ray absorption fine structure spectroscopy. It was found that increase in the synthesis temperature results in an extension of the specific surface area from ∼640 to ∼670 m2/g, enlargement in the average pore size from ∼9 to ∼13 nm, and a decrease in the nitrogen content from ∼4.4 to 2.7 at%. TGA revealed that the samples differ by ∼80 °C in the temperature of nitrogen loss, which was desorbed as the NO species mainly.

Scheme of nitrogen‐doped porous carbon synthesis.
Summertime precipitation over northern Australia in AMIP simulations from CMIP5
Authors: Ackerley D. , Berry G. , Jakob C. , Reeder M. J. , Schwendike J.
Published: October 2014

Tropical precipitation is caused by many processes that occur over a wide range of temporal and spatial scales. Such processes vary from local, diurnal convection driven by a destabilisation of the boundary layer to planetary‐scale systems that result in rainfall over many days. It is therefore important to assess whether general circulation models (GCMs) can represent these processes given that such models are routinely used to project future rainfall in the low latitudes. In this study, we evaluate the rainfall and circulation characteristics of ten GCMs from the Coupled Model Intercomparison Project Phase 5 (CMIP5) over northern Australia. This work shows that the diurnal cycle of the low‐level (925 hPa) flow around the heat low is represented well by the models but the timing of precipitation is not (triggered too early). There is also evidence that mid‐level synoptic systems that are responsible for initiating rain in the observations are also present in all of the models. Nevertheless, the biases in the modelled seasonal mean precipitation seem to be linked to the strength of both the meridional flow into northern Australia and the vertical mass flux. Furthermore, there is also evidence that the representation of convection in these models is likely contributing to both the precipitation and circulation errors over northern Australia.