bluuebunny/crossref_metadata_2025 huggingface dataset:
Poly(L‐histidine)‐chitosan/alginate complex microcapsule as a novel drug delivery agent
Authors: Chen Ai‐Zheng , Chen Mei‐Ying , Wang Shi‐Bin , Huang Xiao‐Nan , Liu Yuan‐Gang , Chen Zong‐Xiang
Published: November 2011

Novel poly(L‐histidine)‐chitosan/alginate complex microcapsules were prepared from biodegradable polymers poly(L‐histidine) (PLHis) in the presence of chitosan at acetate buffer solution pH 4.6. Microcapsules obtained are spherical and well‐dispersed with a smooth surface and a narrow size distribution. The microcapsules can encapsulate the protein model drug hemoglobin (Hb) efficiently. The results show that the complex microcapsules with low, medium, or high molecular weight of chitosan (0.05%, w/v), the highest encapsulation efficiencies obtained are 91.3%, 85.9%, and 94.2% with loading efficiencies of 47.8%, 44.3%, and 39.7%, respectively. The release profiles indicate that Hb‐loaded microcapsules conform to first‐order release kinetic in whole procedure, and 84.8%, 71.4%, and 87.3% of Hb were released during 72‐h incubation in PBS pH6.8 for microcapsules with low, medium, and high molecular weight chitosan (0.05%, w/v), respectively. The results also indicate that particle size and drug loading efficiency have a significant influence on the release profile and encapsulation efficiency. Our results reveal that the PLHis‐chitosan/alginate complex microcapsules are able to encapsulate and release Hb and are potential carriers for protein drugs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of stearic acid and sodium stearate on cast cornstarch films
Authors: Wu Xiao , Chen Yong , Lv Xu‐Chao , Du Zong‐Liang , Zhu Pu‐Xin
Published: November 2011

Stearic acid and sodium stearate were used as lipids to form inclusion complexes with cornstarch through a cooking process, respectively. The complexing index and the surface tension of the cooked pastes were measured. The films of the pastes were formed by casting, paper‐sizing, and paper‐coating methods. X‐ray diffraction and scanning electron microscopy were used to characterize the crystal and surface structures. Such properties of the complex films as the moisture absorption, friction coefficient, and tensile properties were tested. The results reveal that the two lipids could form an inclusion complex with amylose in the cornstarch more or less as a result of forming V‐type crystals that restrained the crystallite size of the B‐type crystal in the starch film. The addition of lipids reduced the sensitivity of the complex films to environmental moisture, decreased the friction coefficient of the films, and visibly increased the smoothness of the surfaces of the films. When the lipids were added in the starch at a weight content of 1%, the elongation at break of the complex film increased and the strength decreased slightly, and above a 1% content of the lipids, the tensile properties of the starch film were greatly deteriorated. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of poly(γ‐methacryloxypropyltrimethoxysilane)‐grafted silica hybrid nanoparticles prepared by surface‐initiated atom transfer radical polymerization
Authors: Wu Ji‐Rong , Lai Guo‐Qiao , Yu Hai‐Jiang , Luo Zheng‐Hong
Published: November 2011

Poly(γ‐methacryloxypropyltrimethoxysilane) (PMPTS)‐grafted silica hybrid nanoparticles were prepared by surface‐initiated atom transfer radical polymerization (SI‐ATRP). The resulting PMPTS‐grafted silica hybrid nanoparticles were characterized using Fourier transform infrared spectroscopy (FTIRS), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), X‐ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM), static water contact angle (WCA) measurement, and thermogravimetric analysis (TGA). Combined FTIRS, NMR, XPS, SEM, and TGA studies confirmed that these hybrid nanoparticles were successfully prepared by surface‐initiated ATRP. SEM and AFM studies revealed that the surfaces of the nanoparticles were rough at the nanoscale. In addition, the results of the static WCA measurements showed that the nanoparticles are of low surface energy and their surface energy reaches as low as 6.10 mN m−1. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Manipulation of enzyme properties by noncanonical amino acid incorporation
Authors: Zheng Shun , Kwon Inchan
Published: November 2011

Since wild‐type enzymes do not always have the properties needed for various applications, enzymes are often engineered to obtain desirable properties through protein engineering techniques. In the past decade, complementary to the widely used rational protein design and directed evolution techniques, noncanonical amino acid incorporation (NCAAI) has become a new and effective protein engineering technique. Recently, NCAAI has been used to improve intrinsic functions of proteins, such as enzymes and fluorescent proteins, beyond the capacities obtained with natural amino acids. Herein, recent progress on improving enzyme properties through NCAAI in vivo is reviewed and the challenges of current approaches and future directions are also discussed. To date, both NCAAI methods‐residue‐ and site‐specific incorporation‐have been primarily used to improve the catalytic turnover number and substrate binding affinity of enzymes. Numerous strategies used to minimize structural perturbation and stability loss of a target enzyme upon NCAAI are also explored. Considering the generality of NCAAI incorporation, we expect its application could be expanded to improve other enzyme properties, such as substrate specificity and solvent resistance in the near future.
A Fluorescence Turn‐on Sensor for Iodide Based on a Thymine–HgII–Thymine Complex
Authors: Ma Boling , Zeng Fang , Zheng Fangyuan , Wu Shuizhu
Published: November 2011

Iodide plays a vital role in many biological processes, including neurological activity and thyroid function. Due to its physiological relevance, a method for the rapid, sensitive, and selective detection of iodide in food, pharmaceutical products, and biological samples such as urine is of great importance. Herein, we demonstrate a novel and facile strategy for constructing a fluorescence turn‐on sensor for iodide based on a T–HgII–T complex (T=thymine). A fluorescent anthracene–thymine dyad (An‐T) was synthesized, the binding of which to a mercury(II) ion lead to the formation of a An‐T–HgII–T‐An complex, thereby quenching the fluorescent emission of this dyad. In this respect, the dyad An‐T constituted a fluorescence turn‐off sensor for mercury(II) ions in aqueous media. More importantly, it was found that upon addition of iodide, the mercury(II) ion was extracted from the complex due to the even stronger binding between mercury(II) ions and iodide, leading to the release of the free dyad and restoration of the fluorescence. By virtue of this fluorescence quenching and recovery process, the An‐T–HgII–T‐An complex constitutes a fluorescence turn‐on sensor for iodide with a detection limit of 126 nM. Moreover, this sensor is highly selective for iodide over other common anions, and can be used in the determination of iodide in drinking water and biological samples such as urine. This strategy may provide a new approach for sensing some other anions.
ChemInform Abstract: An Environmentally Benign Procedure for the Synthesis of Substituted 2‐Thiobenzothiazoles, 2‐Thiobenzoxazoles, 2‐Thiobenzimidazoles, and 1,3‐Oxazolopyridine‐2‐thiols.
Authors: Deligeorgiev Todor G. , Kaloyanova Stefka S. , Lesev Nedyalko Y. , Vaquero Juan J.
Published: November 2011

An improved method for the synthesis of the title compounds is presented which uses glycerol or PEG 400 as solvent under microwave irradiation.
ChemInform Abstract: Efficacy of C—N Coupling Reactions with a New Multinuclear Copper Complex Catalyst and Its Dissociation into Mononuclear Species.
Authors: Zou Yan , Lin Haisheng , Maggard Paul A. , Deiters Alexander
Published: November 2011

A new air‐stable copper(I)‐pyridazine/rhenate hybrid complex is prepared and its activity is explored in C—N coupling.
ChemInform Abstract: Catalytic Intermolecular Allyl—Allyl Cross‐Couplings Between Alcohols and Boronates.
Authors: Jimenez‐Aquino Agustin , Ferrer Flegeau Emmanuel , Schneider Uwe , Kobayashi Shu
Published: November 2011

The presented reaction proceeds under mild conditions with excellent linear‐γ‐selectivity.
ChemInform Abstract: A Simplified Catalytic System for Direct Catalytic Asymmetric Aldol Reaction of Thioamides; Application to an Enantioselective Synthesis of Atorvastatin.
Authors: Kawato Yuji , Iwata Mitsutaka , Yazaki Ryo , Kumagai Naoya , Shibasaki Masakatsu
Published: November 2011

A new second generation lithium‐free Cu catalyst is developed that exhibits an enhanced catalytic efficiency over the previously applied first generation catalyst (Cu(MeCN)4PF6/BPE/LiOAr), which required a tedious preparation process.
ChemInform Abstract: Allyl and Benzyl Dance under Basic Conditions.
Authors: El Kaim Laurent , Grimaud Laurence , Purumandla Srinivas Reddy
Published: November 2011

A new reversible rearrangement is observed when Ugi—Smiles adducts are treated with NaH in MeCN.
ChemInform Abstract: Highly Enantioselective Hydrogenation of 2‐Oxo‐4‐arylbutanoic Acids to 2‐Hydroxy‐4‐arylbutanoic Acids.
Authors: Zhu Lufeng , Chen Houhe , Meng Qinghua , Fan Weizheng , Xie Xiaomin , Zhang Zhaoguo
Published: November 2011

Ruthenium‐catalyzed asymmetric hydrogenation of title oxobutanoic acids (I) proceeds smoothly in the presence of chiral (S)‐SunPhos ligand to give the corresponding hydroxybutanoic acid esters (III) in up to 93% optical purity.
ChemInform Abstract: Base‐Free Palladium‐Catalyzed Sonogashira Coupling Using Organogold Complexes.
Authors: Pankajakshan Sreekumar , Loh Teck‐Peng
Published: November 2011

An effective procedure for the aerobic aryl—alkyne coupling under very mild conditions uses organogold complexes as pseudo‐aryl halides in the Sonogashira coupling and does not require any base, ligand, or inert conditions.
ChemInform Abstract: Direct and Highly Diastereoselective Synthesis of Azaspirocycles by a Dysprosium(III) Triflate Catalyzed Aza‐Piancatelli Rearrangement.
Authors: Palmer Leoni I. , de Alaniz Javier Read
Published: November 2011

The spiro compounds are obtained with trans‐selectivity.
ChemInform Abstract: Methylenecyclopropanes in [4 + 1] Cycloaddition with Enones.
Authors: Inami Tasuku , Sako Saori , Kurahashi Takuya , Matsubara Seijiro
Published: November 2011

The unprecedented type of cycloaddition affords highly substituted dihydrofuran skeletons.
ChemInform Abstract: Asymmetric Decarboxylative Allylation of Oxindoles.
Authors: Franckevicius Vilius , Cuthbertson James D. , Pickworth Mark , Pugh David S. , Taylor Richard J. K.
Published: November 2011

The reversal in stereoselectivity correlates with the size of the oxindole substituent.
ChemInform Abstract: Proline‐Catalyzed Enantioselective Synthesis of Aza‐Quaternary Carbon Derivatives.
Authors: Li Liqi , Han Manyi , Xiao Mingxing , Xie Zhixiang
Published: November 2011

Reaction of indolinones with carbonyl compounds under conditions A) is described as an efficient process to construct chiral aza‐quaternary carbon addition products with good regio‐ and stereoselectivity.
ChemInform Abstract: Palladium‐Mediated Intramolecular C—O and C—C Coupling Reactions: An Efficient Synthesis of Benzannulated Oxazepino‐ and Pyranocarbazoles.
Authors: Prabakaran Kumaresan , Zeller Matthias , Prasad Karnam Jayarampillai Rajendra
Published: November 2011

Depending on the conditions used, the reaction of 1‐hydroxycarbazoles (I) with acid chlorides (II) give the corresponding N‐ or O‐benzoylated products selectively.
ChemInform Abstract: Synthesis, Characterization, and Derivatization of Some Novel Types of Fluorinated Mono‐ and Bis‐Imidazolidineiminothiones with Antitumor, Antiviral, Antibacterial, and Antifungal Activities.
Authors: El‐Sharief Marwa A. M. Sh. , Moussa Ziad , El‐Sharief Ahmed M. Sh.
Published: November 2011

A series of title compounds of type (III) and (IV) is prepared and tested for their biological activities.
ChemInform Abstract: A Regioselective and Diastereoselective Synthesis of New Spiro‐isoxazolidines via 1,3‐Dipolar Cycloaddition of Stable Isatin Ketonitrone and Various Dipolarophiles.
Authors: Mehrdad Morteza , Faraji Laleh , Jadidi Khosrow , Eslami Parisa , Sureni Hossein
Published: November 2011

Optimum reaction conditions are studied for the regioselective and diastereoselective synthesis of spiro‐isoxazolidines of type (V) or (VII) via 1,3‐dipolar cycloaddition reaction of the stable isatin ketonitrone (III) and various dipolarophiles of type (IV) or (VI).
ChemInform Abstract: Synthesis of Epoxybenzo[d]isothiazole 1,1‐Dioxides via a Reductive‐Heck, Metathesis‐Sequestration Protocol.
Authors: Asad Naeem , Hanson Paul R. , Long Toby R. , Rayabarapu Dinesh K. , Rolfe Alan
Published: November 2011

An atom‐economical protocol for the synthesis and purification of the compounds (III) and (V) is presented.
ChemInform Abstract: Nickel‐Catalyzed Cycloaddition of o‐Arylcarboxybenzonitriles and Alkynes via Cleavage of Two Carbon—Carbon σ Bonds.
Authors: Nakai Kenichiro , Kurahashi Takuya , Matsubara Seijiro
Published: November 2011

The reaction works well under catalysis of an optimized system with symmetrical and unsymmetrical internal alkynes to give 3,4‐disubstituted coumarins, but fails for terminal alkynes.
ChemInform Abstract: First Synthesis of 3‐Amino‐2‐arylimidazo[1,2‐b]pyridazines by Groebke—Blackburn Reaction.
Authors: Lamberth Clemens
Published: November 2011

The title reaction can be achieved with different isocyanides and benzaldehydes giving products (IV) with a broad variety of substituents in the imidazole moiety.
ChemInform Abstract: Novel Synthesis and Biological Activity of 2‐Substituted Derivatives of 3‐Cyano‐4‐imino‐2‐methylthio‐8‐methoxy‐4H‐pyrimido[2,1‐b] [1,3]benzothiazole and 3‐Amino‐4‐imino‐8‐methoxy‐2H‐pyrazolo[3′,4′:4,5]pyrimido[2,1‐b] [1,3]benzothiazole.
Authors: Badne S. G. , Swamy D. K. , Bhosale V. N. , Kuberkar S. V.
Published: November 2011

All synthesized compounds are screened for their antimicrobial activity against S.
ChemInform Abstract: Pyrrolo[2,3‐d]pyrimidine‐Core‐Extended π‐Systems: Synthesis of 2,4,7‐Triarylpyrrolo[2,3‐d]pyrimidines.
Authors: Tumkevicius Sigitas , Dodonova Jelena
Published: November 2011

N‐Arylation of diarylpyrrolopyrimidine substrates provides novel fluorescent triaryl derivatives.
ChemInform Abstract: Synthesis of Some Pyrimido[4,5‐b]quinoline Derivatives.
Authors: Marjani Ahmad Poursattar , Khalafy Jabbar , Ebrahimlo Ali Reza Molla , Prager Rolf H.
Published: November 2011

A simple one‐step synthesis of derivatives (III) of a novel azetopyrimidoquinoline ring system (14 examples) is given.
ChemInform Abstract: A Mild One‐Pot Method for Conversion of Various Steroidal Secondary Alcohols into the Corresponding Olefins.
Authors: Kumar Raju Ranjith , Haveli Shrutisagar Dattatraya , Kagan Henri B.
Published: November 2011

The use of Tf2O in the presence of excess base is investigated for the direct dehydration process.
ChemInform Abstract: Concise Syntheses of Strychnine and Englerin A: The Power of Reductive Cyclizations Triggered by Samarium Iodide
Authors: Szostak Michal , Procter David J.
Published: November 2011

Review: 37 refs.
ChemInform Abstract: Synthesis of Natural Products via Intramolecular Oxazole—Olefin Diels—Alder Reaction
Authors: Ohba Masashi
Published: November 2011

Review: 57 refs.
ChemInform Abstract: Bisphosphacycles: From DuPhos and BPE to a Diverse Set of Broadly Applied Ligands
Authors: Zhang Weicheng , Zhang Xumu
Published: November 2011

Review: 130 refs.
ChemInform Abstract: Synthetic Studies Toward the Spiroimine Unit of the Spirolides
Authors: Gueret Stephanie M. , Brimble Margaret A.
Published: November 2011

Review: 28 refs.
ChemInform Abstract: Biomimetic Catalysis
Authors: Marchetti Louis , Levine Mindy
Published: November 2011

Review: 272 refs.
ChemInform Abstract: Design of Frustrated Lewis Pair Catalysts for Metal‐Free and Selective Hydrogenation
Authors: Soos Tibor
Published: November 2011

Review: 24 refs.
ChemInform Abstract: 2‐Oxoglycosyl (“Ulosyl”) and 2‐Oximinoglycosyl Bromides: Versatile Donors for the Expedient Assembly of Oligosaccharides with β‐D‐Mannose, β‐L‐Rhamnose, N‐Acetyl‐β‐D‐mannosamine, and N‐Acetyl‐β‐D‐mannosaminuronic Acid Units
Authors: Lichtenthaler Frieder W.
Published: November 2011

Review: 339 refs.
ChemInform Abstract: Biomimetic Synthesis of Indole‐Oxidized and Complex Peptide Alkaloids
Authors: Arndt Hans‐Dieter , Milroy Lech‐Gustav , Rizzo Stefano
Published: November 2011

Review: 102 refs.
ChemInform Abstract: Biomimetic Synthesis of Azole‐ and Aryl‐Peptide Alkaloids
Authors: Arndt Hans‐Dieter , Lichtenecker Roman , Loos Patrick , Milroy Lech‐Gustav
Published: November 2011

Review: 179 refs.
ChemInform Abstract: Fischer—Tropsch Chemistry at Room Temperature?
Authors: Gerlach Deidra L. , Lehnert Nicolai
Published: November 2011

Review: 19 refs.
ChemInform Abstract: Multifunctional Poly(ethylene glycol)s
Authors: Obermeier Boris , Wurm Frederik , Mangold Christine , Frey Holger
Published: November 2011

Review: 129 refs.
ChemInform Abstract: Making Carbon Nanotubes Biocompatible and Biodegradable
Authors: Bianco Alberto , Kostarelos Kostas , Prato Maurizio
Published: November 2011

Review: 43 refs.
ChemInform Abstract: Nanoparticulate Devices for Brain Drug Delivery
Authors: Celia Christian , Cosco Donato , Paolino Donatella , Fresta Massimo
Published: November 2011

Review: 181 refs.
ChemInform Abstract: Nickel‐Catalyzed Cross‐Coupling of Non‐Activated Alkyl Halides: A Mechanistic Perspective
Authors: Hu Xile
Published: November 2011

Review: 92 refs.
Influence of GaN substrate off‐cut on properties of InGaN and AlGaN layers
Authors: Sarzynski M. , Leszczynski M. , Krysko M. , Domagala J. Z. , Czernecki R. , Suski T.
Published: November 2011

This paper summarizes the knowledge how off‐orientation involving lattice planes not parallel to the surface influences properties of AlGaN and InGaN layers. The following issues are presented: (i) morphology of GaN and InGaN layers, (ii) unit cell deformation in AlGaN and InGaN layers, (iii) cracking of AlGaN layers, and (iv) In incorporation into InGaN layers. Finally, laterally patterned on‐axis c ‐plane GaN substrates were successfully used to construct violet laser diodes as well as first multicolour laser diode arrays. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
“Cost” of virginity in wild Drosophila melanogaster females
Authors: Markow Therese Ann
Published: November 2011

Laboratory studies have revealed a significant “cost of mating” to Drosophila melanogaster females in the form of reduced longevity. The effect is attributable to nonsperm components of the ejaculate. Female D. melanogaster are known to mate up to six times in nature, and given that they do not typically remate daily, it raises the question as to the extent to which the longevity of wild mated females is reduced. Here I addressed this question by comparing the longevity of wild virgin females, collected as they emerged from rotting fruit, to the longevity of randomly collected mature females at the same site. Because the randomly collected females all were inseminated and were fully pigmented at the time of collection, they already were older than the virgins when the experiment began. Contrary to expectations from laboratory studies, the older, mated females lived significantly longer than the virgins. Rather than a “cost of mating,” there appears to be a “cost of virginity” to female D. melanogaster in the wild.
Humid tropical rain forest has expanded into eucalypt forest and savanna over the last 50 years
Authors: Tng David Y. P. , Murphy Brett P. , Weber Ellen , Sanders Gregor , Williamson Grant J. , Kemp Jeanette , Bowman David M. J. S.
Published: November 2011

Tropical rain forest expansion and savanna woody vegetation thickening appear to be a global trend, but there remains uncertainty about whether there is a common set of global drivers. Using geographic information techniques, we analyzed aerial photography of five areas in the humid tropics of northeastern Queensland, Australia, taken in the 1950s and 2008, to determine if changes in rain forest extent match those reported for the Australian monsoon tropics using similar techniques. Mapping of the 1950s aerial photography showed that of the combined study area (64,430 ha), 63% was classified as eucalypt forests/woodland and 37% as rain forest. Our mapping revealed that although most boundaries remained stable, there was a net increase of 732 ha of the original rain forest area over the study period, and negligible conversion of rain forest to eucalypt forest/woodland. Statistical modeling, controlling for spatial autocorrelation, indicated distance from preexisting rain forest as the strongest determinant of rain forest expansion. Margin extension had a mean rate across the five sites of 0.6 m per decade. Expansion was greater in tall open forest types but also occurred in shorter, more flammable woodland vegetation types. No correlations were detected with other local variables (aspect, elevation, geology, topography, drainage). Using a geographically weighted mean rate of rain forest margin extension across the whole region, we predict that over 25% of tall open forest (a forest type of high conservation significance) would still remain after 2000 years of rain forest expansion. This slow replacement is due to the convoluted nature of the rain forest boundary and the irregular shape of the tall open forest patches. Our analyses point to the increased concentration of atmospheric CO2as the most likely global driver of indiscriminate rain forest expansion occurring in northeastern Australia, by increasing tree growth and thereby overriding the effects of fire disturbance.
Research on capacity addition using market model with transmission congestion under competitive environment
Authors: Katsura Yasufumi , Attaviriyanupap Pathom , Kataoka Yoshihiko
Published: November 2011

In this research, the fundamental premises for deregulation of the electric power industry are reevaluated. The authors develop a simple model to represent the wholesale electricity market with a highly congested network. The model is developed by simplifying the power system and market in the New York ISO based on available data for the New York ISO in 2004 along with some estimation. Based on the developed model and construction cost data from the past, the economic impact of transmission line addition on market participants and the impact of deregulation on power plant additions in a market with transmission congestion are studied. Simulation results show that market signals may fail to facilitate proper capacity additions and results in the undesirable overconstruction and insufficient construction cycle of capacity addition. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(3): 11–20, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21013
Slow pain generation model caused by mechanical stimulus based on the laminated structure of skin
Authors: Matsunaga Nobutomo , Akayama Seiko , Kawaji Shigeyasu
Published: November 2011

The ability of autonomous robots to learn from the experience of the subjective feeling of pain can be an important advance of robot development. In our previous studies we examined a model of artificial superficial pain caused by impact and proposed a mechanism of pain transmission focused on the input–output relationships. However, the mechanism of the pain generation has not been studied yet. In this paper, the model of slow pain taking into account the skin dynamics is proposed. Using FEM simulations we demonstrated that the strain energy density (SED) arising at inter‐layer borders is related to the subjective pain level. The proposed pain model was evaluated using the experimental pain caused by quasi‐static motion. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(3): 31–41, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21161
Titanium–Imido Complexes with Pendant Groups – Synthesis, Characterization, and Evaluation of Their Role as Precatalysts for Ethylene Polymerization
Authors: Nguyen Viet‐Hoang , Vendier Laure , Etienne Michel , Despagnet‐Ayoub Emmanuelle , Breuil Pierre‐Alain R. , Magna Lionel , Proriol David , Olivier‐Bourbigou Hélène , Lorber Christian
Published: November 2011

The synthesis of several anilines (ArPGNH2) substituted in the ortho position with pendant groups (PGs, terminated by potentially coordinative arene, thienyl, furanyl, or pyridyl functionalities) was accomplished by a two‐ to five‐step synthesis in good yields. The ArPGNH2 proligands were used for the preparation of titanium complexes starting from Ti(NMe2)4 in the presence of excess Me3SiCl. Complexes of the general formula [Ti(NArPG)Cl2(NHMe2)x] (x = 1, 2), which are supported by a terminal imido functionality, were obtained in 60–95 % yield. The nature of the pendant group influences the coordination mode of the ligand. Although only monodentate imido linkages have been observed with ligands where PG is arene, thiophene, and furan, ligands with substituted pyridine sidearms lead to chelating imido–donor functionalities. The potential hemilabile behavior of some imido–donor ligands, which results from the reversible coordination of the side arm, was studied by variable‐temperature 1H NMR spectroscopy. These compounds were evaluated as precatalysts for ethylene polymerization with various aluminum cocatalysts. Ultrahigh molecular‐weight (UHMW) polyethylenes were obtained. All compounds were fully characterized by spectroscopic methods (1H and 13C NMR), and elemental analysis and some were also characterized by single‐crystal X‐ray diffraction.
Catalyst‐Free Suzuki‐Type Coupling of Allylic Bromides with Arylboronic Acids
Authors: Scrivanti Alberto , Beghetto Valentina , Bertoldini Matteo , Matteoli Ugo
Published: November 2011

The coupling of arylboronic acids with electron‐rich allylic bromides is accomplished in the absence of any transition‐metal catalyst through conventional heating. The reaction is completely regioselective, affording only the α‐coupled product, and can be carried out under mild aerobic conditions in an organic solvent; the presence of a base is required.
Analysis of mucosal mucins separated by SDS‐urea agarose polyacrylamide composite gel electrophoresis
Authors: Issa Samah M. A. , Schulz Benjamin L. , Packer Nicolle H. , Karlsson Niclas G.
Published: November 2011

Efficient separation of mucins (200 kDa–2 MDa) was demonstrated using gradient SDS agarose/polyacrylamide composite gel electrophoresis (SDS‐AgPAGE). Inclusion of urea (SDS‐UAgPAGE) in the gels casting were shown to have no effect on the migration of mucins in the gel and allowed casting of gel at room temperature. This simplified the procedure for multiple casting of agarose polyacrylamide gradients and increased reproducibility of these gels. Hence, the implementation of urea makes the technique applicable for high throughput isolation and screening of mucin oligosaccharides by LC‐MS after releasing the oligosaccharides from isolated, blotted mucin subpopulations. It was also shown that the urea addition had no effect on other supporting applications such as western and lectin blotting. In addition, identification of the mucin protein after tryptic digestion and LC‐MS was possible and no protein carbamylation due to the presence of urea in the gel was detected. LC‐MS software developed for metabolomic analysis was used for O‐linked oligosaccharide detection and differential display of various mucin samples. Using this method, heterogeneous glycosylation of mucins and mucin‐type molecules isolated by SDS‐AgPAGE and SDS‐UAgPAGE was shown to consist of more than 80 different components in a single band, and in the extreme cases, up to 300–500 components (MUC5B/AC from saliva and sputum and). Metabolomic software was also used to show that the migration of mucin isoforms within the gel is due to heterogeneous size distribution of the oligosaccharides, with the slower migrating bands enriched in high‐molecular‐weight oligosaccharides.
A new anticancer compound, Oblongifolin C, inhibits tumor growth and promotes apoptosis in HeLa cells through bax activation
Authors: Feng Chao , Zhou Li‐Ying , Yu Ting , Xu Gang , Tian Hong‐Lei , Xu Jin‐Jie , Xu Hong‐Xi , Luo Kathy Qian
Published: November 2011

Oblongifolin C (OC) was identified as a potent apoptosis inducer from an herbal plant, Garcinia yunnanensis, during our previous bioassay‐guided drug screening. In this study, we investigated the signaling pathways through which OC activated apoptosis in HeLa cells. We also compared the IC50 values of OC with that of etoposide, paclitaxel and vinblastine in multiple cancer cell lines including HER2 and P‐glycoprotein overexpressing cells. In addition, the in vivo antitumor effect of OC was studied in nude mice model. Our results showed that OC induced a caspase‐dependent apoptosis by triggering a series of events in HeLa cells including Bax translocation, cytochrome c release, caspase‐3 activation, chromosome fragmentation followed by caspase‐8 activation, Bid cleavage and eventually cell death. Addition of a pan‐caspase inhibitor or overexpression of an anti‐apoptotic protein, Bcl‐xL, prevented OC‐induced cell death. Moreover, OC exhibited a wide anticancer spectrum in multiple cancer cell lines with comparable IC50 values, regardless of the expression levels of HER2 and P‐glycoprotein. In contrast, the IC50 values of three clinical anticancer drugs, etoposide, paclitaxel and vinblastine were significantly elevated in HER2 and/or P‐glycoprotein overexpressing cells. Furthermore, OC showed a similar antitumor effect but lower general toxicity than etoposide against xenografted human tumors in nude mice model. All these data suggested that OC is a promising apoptosis inducer with the potential to be developed into a clinical anticancer drug.
In vivo oxide‐induced stress corrosion cracking of Ti‐6Al‐4V in a neck–stem modular taper: Emergent behavior in a new mechanism of in vivo corrosion
Authors: Gilbert Jeremy L. , Mali Sachin , Urban Robert M. , Silverton Craig D. , Jacobs Joshua J.
Published: November 2011

In vivo modular taper corrosion in orthopedic total joint replacements has been documented to occur for head–neck tapers, modular‐body tapers, and neck–stem tapers. While the fretting corrosion mechanism by which this corrosion occurs has been described in the literature, this report shows new and as yet unreported mechanisms at play. A retrieved Ti‐6Al‐4V/Ti‐6Al‐4V neck–stem taper interface, implanted for 6 years is subjected to failure analysis to document taper corrosion processes that lead to oxide driven crack formation on the medial side of the taper. Metallurgical sectioning techniques and scanning electron microscopy analysis are used to document the taper corrosion processes. The results show large penetrating pitting attack of both sides of the taper interface where corrosion selectively attacks the beta phase of the microstructure and eventually consumes the alpha phase. The pitting attack evolves into plunging pits that ultimately develop into cracks where the crack propagation process is one of corrosion resulting in oxide formation and subsequent reorganization. This process drives open the crack and advances the front by a combination of oxide‐driven crack opening stresses and corrosion attack at the tip. The oxide that forms has a complex evolving structure including a network of transport channels that provide access of fluid to the crack tip. This emergent behavior does not appear to require continued fretting corrosion to propagate the pitting and cracking. This new mechanism is similar to stress corrosion cracking where the crack tip stresses arise from the oxide formation in the crack and not externally applied tensile stresses. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 584–594, 2012.
Time‐optimized X‐ray micro‐CT imaging of polymer based scaffolds
Authors: Morris David E. , Mather Melissa L. , Simon Carl G. , Crowe John A.
Published: November 2011

Although X‐ray microscopic computed tomography is widely used to assess the structural properties of polymeric tissue scaffolds its validity is dependent on the quality of the images obtained. Here, the role of resolution, integration time, image averaging, and X‐ray power on the accurate determination of scaffold porosity, while aiming to minimize imaging time, was investigated. This work identified key parameters for optimization and a methodology to vary them to improve results. Based on this, guidelines were developed to assist in the selection of image acquisition parameters to allow rapid and accurate scaffold imaging as required for mass manufacture. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 360–367, 2012.
The effect of strontium incorporation into hydroxyapatites on their physical and biological properties
Authors: Ni Guo‐Xin , Shu Bin , Huang Guotao , Lu William W. , Pan Hao‐Bo
Published: November 2011

In this study, the effects of a series of strontium (Sr)‐substituted HA ceramics (0, 1, 5, and 10 mol % Sr substitution) were tested on their physical and biological properties. The crystal structure, composition, and solubility were investigated by TEM, XRD, and solid titration solubility isotherms, respectively. In addition, rat MSCs were cultured with culture media containing ions released from the strontium‐substituted HA ceramics as they dissolved. MTT test, alkaline phosphatase activity, and osteoblast transcription factor gene (cbfa1) expression were conducted at different time points. Our results suggested that HA with Sr substitution may change its physical properties, especially its solubility, and consequently enhance undifferentiated MSCs into osteoblast lineage. The results from this and the previous study suggested that 5–10 mol % Sr substitution into HA may be a suitable choice for its use in bone regenerative field. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 100B: 562–568, 2012.
Reconstruction of the complete loss of upper and lower lips with a chimeric anterolateral thigh flap: A case report
Authors: Lai Chien‐Liang , Ou Kuang‐Wen , Chiu Wen‐Kuan , Chen Shyi‐Gen , Chen Tim‐Mo , Li Hsiao‐Ping , Chang Shun‐Cheng
Published: November 2011

It is difficult to totally reconstruct the lips and achieve good functional and aesthetic results, such as oral sphincter function, sensation, appearance, color, and movement. There have been few reports of reconstructing complete lip defects. We present a case of completely reconstructing the lip defects of a 55‐year‐old patient who had verrucous carcinoma of the buccal mucosa and lips. Extensive ablation was performed by wide bilateral excision of the buccal mucosa and marginal resection of the anterior mandible and both lips. The tongue, partial tongue base mucosa, and retromolar trigone were preserved. To reconstruct and resurface the intraoral and lip defects nearly totally, we applied a free anterolateral thigh (ALT) flap in chimeric style with two independent sets of perforators and skin islands. To achieve better oral function and cosmetics, revisions of the ALT flap, full‐thickness scrotal skin grafting, autologous fat grafting, and skin tattooing were done in stages. Postoperative oral sphincter function was obtained without drooling; the general appearance of the lips was also acceptable. © 2011 Wiley Periodicals, Inc. Microsurgery, 2012.
Intra‐ and internerve cross‐sectional area variability: New ultrasound measures
Authors: Padua Luca , Martinoli Carlo , Pazzaglia Costanza , Lucchetta Marta , Granata Giuseppe , Erra Carmen , Briani Chiara
Published: November 2011

Introduction: Nerve involvement in immune‐related neuropathies is non‐homogeneous, and therefore characterization of ultrasound (US) abnormalities is difficult. We developed two measures to quantify US abnormalities in immune‐related neuropathies. Methods: Intranerve cross‐sectional area (CSA) variability for each nerve was calculated as: maximal CSA/minimal CSA. Internerve CSA variability for each patient was calculated as: maximal intranerve CSA variability/minimal intranerve CSA variability. Six patients underwent US evaluation of the median, ulnar, and fibular nerves, and the abnormalities were scored with our newly developed measures. Results: The new measures were applicable to all nerves and patients. The highest degree of intra‐ and internerve CSA variability was observed in multifocal motor neuropathy, consistent with the asymmetric characteristics of this neuropathy. Conclusions: The application of intra‐ and internerve CSA variability measures allows us to quantify the heterogeneity of nerves and nerve segments and identify different US patterns in diverse immune‐related neuropathies. Muscle Nerve, 2012
Hybrid functional calculations of native point defects in InN
Authors: Janotti A. , Lyons J. L. , Van de Walle C. G.
Published: November 2011

By means of hybrid functional calculations we investigate the role of native point defects in the electronic properties of InN. We find that nitrogen vacancies are the most energetically favorable defects and act as shallow donors for Fermi‐level positions within the band gap. However, their formation energies are too high in order to explain the observed unintentional n‐type conductivity in as‐grown or annealed InN films. A transition from donor to acceptor behavior occurs at 1.9 eV above the valence‐band maximum (VBM), indicating that if nitrogen vacancies are intentionally introduced to increase the carrier concentration, e.g., by irradiating the InN crystals, the Fermi level will saturate at 1.3 eV above the conduction‐band minimum (CBM). The other donor defects, i.e., the nitrogen split interstitial, nitrogen antisite, and indium antisite, have even higher formation energies, and thus are also unlikely sources of unintentional n‐type conductivity. The indium vacancies and nitrogen interstitials occupying the octahedral sites are deep acceptors with transition levels resonant in the conduction band. These defects exhibit very high formation energies even for Fermi levels well above the CBM. Our results indicate that InN can support very high electron concentrations before compensation by native acceptor defects takes place.
Assessing system operation skills in robotic surgery trainees
Authors: Kumar Rajesh , Jog Amod , Malpani Anand , Vagvolgyi Balazs , Yuh David , Nguyen Hiep , Hager Gregory , Chen Chi Chiung Grace
Published: November 2011

Background

With increased use of robotic surgery in specialties including urology, development of training methods has also intensified. However, current approaches lack the ability to discriminate between operational and surgical skills.

Methods

An automated recording system was used to longitudinally (monthly) acquire instrument motion/telemetry and video for four basic surgical skills – suturing, manipulation, transection, and dissection. Statistical models were then developed to discriminate the human–machine skill differences between practicing expert surgeons and trainees.

Results

Data from six trainees and two experts was analyzed to validate the first ever statistical models of operational skills, and demonstrate classification with very high accuracy (91.7% for masters, and 88.2% for camera motion) and sensitivity.

Conclusions

The paper reports on a longitudinal study aimed at tracking robotic surgery trainees to proficiency, and methods capable of objectively assessing operational and technical skills that would be used in assessing trainee progress at the participating institutions. Copyright © 2011 John Wiley & Sons, Ltd.
Phosphorylation events during viral infections provide potential therapeutic targets
Authors: Keating Julie A. , Striker Rob
Published: November 2011

For many medically relevant viruses, there is now considerable evidence that both viral and cellular kinases play important roles in viral infection. Ultimately, these kinases, and the cellular signaling pathways that they exploit, may serve as therapeutic targets for treating patients. Currently, small molecule inhibitors of kinases are under investigation as therapy for herpes viral infections. Additionally, a number of cellular or host‐directed tyrosine kinase inhibitors that have been previously FDA approved for cancer treatment are under study in animal models and clinical trials, as they have shown promise for the treatment of various viral infections as well. This review will highlight the wide range of viral proteins phosphorylated by viral and cellular kinases, and the potential for variability of kinase recognition sites within viral substrates to impact phosphorylation and kinase prediction. Research studying kinase‐targeting prophylactic and therapeutic treatments for a number of viral infections will also be discussed. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of geometry of a vertically aligned carbon nanotube pillar array on its field‐emission properties
Authors: Sato Hideki , Haruki Kazuo , Watanabe Masaaki , Hata Koichi , Saito Yahachi
Published: November 2011

The influence of geometry of a carbon nanotube (CNT) pillar array on its field‐emission (FE) properties was investigated for the purpose of designing a high‐efficiency CNT field‐emitter array. The dependence of the FE properties (turn‐on voltage and emission site distribution) on the pillar pitch and shape was examined. The examination of the FE properties using a square‐shaped pillar array showed that the pillar pitch is not a dominant factor to lower the turn‐on voltage and improve the uniformity of emission sites. On the other hand, the change of the pillar shape from a square to a ‘mountain shape’ improved the FE properties. This improvement is due to the dispersed growth morphology, which reduces the field‐screening effect at the top of the mountain‐shaped pillars. This result indicates that controlling the pillar shape is effective for improving the FE properties of the CNT pillar array. Copyright © 2011 John Wiley & Sons, Ltd.
The defects in cell wall integrity and G2–M transition of the ∆htl1 mutant are interconnected
Authors: Wang Shan‐Li , Cheng Ming‐Yuan
Published: November 2011

The Saccharomyces cerevisiae RSC (remodel the structure of chromatin) complex is involved in functions associated with the transcriptional regulation, cell cycle progression, DNA damage repair and cell wall integrity. Here we investigate the cellular functioning of HTL1, which encodes a non‐essential subunit of the RSC complex. The results show that the ∆htl1 mutant displays a characteristic defect in cell wall integrity, and the phenotype of the ∆htl1 cells, which include the cell wall defect, temperature sensitivity and ploidy increase, are rescued by the osmotic stabilizer sorbitol but not by overexpression of PKC1, the signalling kinase important for the cell wall biogenesis and stress response. In addition, the expression level of Slt2p, the MAP kinase downstream of the cell wall integrity pathway, is upregulated in ∆htl1 cells. Furthermore, the mitotic arrest of the ∆htl1 mutant is moderated by 1 m sorbitol and deletion of SLT2. The present findings suggest that HTL1 may play a role that is different from other RSC components in terms of cell wall integrity and the G2–M transition. The results also suggest that the defects in cell wall integrity and the G2–M transition of the ∆htl1 mutant are interconnected. Copyright © 2011 John Wiley & Sons, Ltd.
Patient safety risk factors in minimally invasive surgery: a validation study
Authors: Rodrigues Sharon P. , ter Kuile Moniek , Dankelman Jenny , Jansen Frank W.
Published: November 2011

This study was conducted to adapt and validate a patient safety (PS) framework for minimally invasive surgery (MIS) as a first step in understanding the clinical relevance of various PS risk factors in MIS. Eight patient safety risk factor domains were identified using frameworks from a systems approach to patient safety. A questionnaire was drafted containing 34 questions. Three experts in the field of patient safety critically reviewed the questionnaire on clinical relevance and completeness. The questionnaire was distributed among known patient safety experts in person and also sent electronically. A total of 41 questionnaires were distributed and the response rate was 71%. The intraclass correlation coefficient was 0.42 representing moderate agreement. For seven of nine risk domains, Cronbach’s alpha was sufficient (α > 0.7). Mean scores of the risk domains showed the following order of influence on patient safety from high to low: surgeon’s experience [6.6, standard deviation (SD) 0.5], technical skills surgeon (6.6, SD 0.7), technology (5.9, SD 1.1), complications (5.9, SD 1.2), social interaction (5.0, SD 1.0), leadership surgeon (5.4, SD 1.2), blood loss (5.0, SD 1.2), length of surgery (5.0, SD 1.3), surgical team (4.9, SD 1.3), fallibility (4.9, SD 1.3), patient (4.5, SD 1.5), safety measures (4.4, SD 1.5), and finally environment(3.9, SD 1.5). This study is an initiative to give insight into clinical relevance of the maze of PS risk factors in MIS. All investigated risk domains were considered to be of noticeable influence on PS. Nevertheless, it is possible to prioritize various risk domains. In fact, experience and technical skills of the surgeon, technology, and complications are rated as the most important risk factors, closely followed by social interaction and leadership of the surgeon. Patient, safety measures, and environment are rated as the least important risk factors.
Oxidative stress in Phenylketonuria: future directions
Authors: Rocha Júlio César , Martins Maria João
Published: November 2011

Phenylketonuria represents the most prevalent inborn error of amino acid metabolism. In early diagnosed patients adequate and continued dietary treatment results in a good neurologic outcome. Natural protein and phenylalanine‐restricted diet, even if rich in fruits and vegetables, represents a serious risk for nutritional deficiencies, albeit universally accepted. In the last few years, a growing number of reports have been describing oxidative stress as a concern in phenylketonuric patients. The diet itself includes good sources of dietary antioxidants (phytochemicals, some vitamins and minerals) but also a risk factor for some deficiencies (selenium, zinc, ubiquinone‐10 and L‐carnitine). Additionally, the extreme stringency of the diet may impose a reduced synthesis of endogenous antioxidants (like ubiquinone‐10 and glutathione). Furthermore, increased phenylalanine levels, and its metabolites, may enhance the endogenous synthesis of reactive species and free radicals and/or interfere with the endogenous synthesis of enzymatic antioxidants (like glutathione peroxidase). Therefore, oxidative stress will probably increase, mainly in late diagnosed patients or in those with bad metabolic control. Considering the known association between oxidative stress, obesity and cardiovascular disease, it seems advisable to look further to the impact of oxidative stress on body macromolecules and structures (like lipoprotein oxidation), especially in phenylketonuric patients with late diagnosis or bad metabolic control, in order to prevent future increased risks. Recommendations for PKU patient's clinical follow‐up improvement and educational goals are included.