bluuebunny/crossref_metadata_2025 huggingface dataset:
Au on Nanosized NiO: A Cooperative Effect between Au and Nanosized NiO in the Base‐Free Alcohol Oxidation
Authors: Villa Alberto , Chan‐Thaw Carine E. , Veith Gabriel M. , More Karren L. , Ferri Davide , Prati Laura
Published: August 2011

Nanosized NiO has been synthesized and used as a support for polyvinyl alcohol‐protected Au nanoparticles. This catalytic system exhibits an extraordinary performance in the base‐free liquid phase oxidation of alcohols compared to the same Au supported on a commercial, micrometersized NiO. This enhancement in activity cannot be solely attributed to the improved basic properties of the support. A cooperative effect between Au nanoparticles and nanosized NiO is envisaged.
Mixed Conductivity, Nonstoichiometric Oxygen, and Oxygen Permeation Properties in Co‐Doped Sr3Ti2O7−δ
Authors: Nuansaeng Sirikanda , Yashima Masatomo , Matsuka Maki , Ishihara Tatsumi
Published: August 2011

Electrical conductivity and oxygen permeation rates in Co‐doped Sr3Ti2O7−δ with Ruddesden–Popper type structures were investigated. The effects of metal dopants (M) in the Ti site of Sr3Ti2(M)O7−δ on the mixed conductivity were also studied. Doping of Sr3Ti2O7−δ with Co was found to be effective for improving the electrical conductivity as well as the oxygen permeation rate, which could be assigned to the increased oxygen vacancy concentration by doping Co3+ into Ti4+ sites. The nonstoichiometric oxygen of these oxides was measured by using a thermal gravimetric method. The creation of oxygen vacancies, which is compensated with Co3+ doping, leads to higher oxide ion conductivity. The oxygen permeation rate monotonously increased with increasing amounts of Co in the Ti site. Sr3Ti0.8Co1.2O7−δ exhibited high oxide ion conductivity and a large oxygen permeation rate. The highest oxygen permeation rate achieved a value of 2.02 cc min−1 cm−2 at 1273 K for Sr3Ti0.8Co1.2O7−δ. Neutron diffraction analysis and redox titration suggests that the oxygen diffusion occurs through oxygen vacancies in the perovskite block, but not through excess oxygen in the rock salt block.
Visual Scanometric Detection of DNA through Silver Enhancement Regulated by Gold‐Nanoparticle Aggregation with a Molecular Beacon as the Trigger
Authors: Ji Hanxu , Dong Haifeng , Yan Feng , Lei Jianping , Ding Ling , Gao Wenchao , Ju Huangxian
Published: August 2011

A convenient and label‐free scanometric approach for DNA assay was designed by integrating a metal‐ion‐mediated conformational molecular beacon (MB) and silver‐signal amplification regulated by gold‐nanoparticle (AuNP) aggregation. The strategy was based on displacing the interaction between the target DNA sequence and a competitor Hg2+ ion with a link DNA sequence. In the absence of the target DNA sequence, a link DNA sequence interacted with the Hg2+ ions, thus forming an inactive cyclic conformation of the MB. This result led to the poor aggregation of polyadenosine‐functionalized AuNPs (A‐AuNP). In the presence of a target DNA sequence with a stronger affinity than that of the competitor, hybridization between the link DNA and target DNA sequences turned on the trigger. The polythymidine end of the resulting linear duplex structure could react with A‐AuNP, thus leading to a cross‐linking aggregation. This aggregation weakened AuNP‐catalyzed silver enhancement on a spot substrate. Further, by using scanometric detection, the concentration of the target DNA sequence could be conveniently read out within a linear range from 1.0 to 30 nM. Interestingly, in the same amount of Hg2+ ions, one‐base mismatched DNA showed only 22 % of the relative gray‐scale intensity for the target DNA sequence at the same concentration, thus indicating good specificity. The designed approach, with the help of the ion‐mediated conformational MB, was simple, cost effective, adaptable, and convenient and provided significant potential applications in clinical analysis.
Progress in Crystal Structure Prediction
Authors: Kendrick John , Leusen Frank J. J. , Neumann Marcus A. , van de Streek Jacco
Published: August 2011

The results of the application of a density functional theory method incorporating dispersive corrections in the 2010 crystal structure prediction blind test are reported. The method correctly predicted four out of the six experimental structures. Three of the four correct predictions were found to have the lowest lattice energy of any crystal structure for that molecule. The experimental crystal structures for all six compounds were found during the structure generation phase of the simulations, indicating that the tailor‐made force fields used for screening structures were valid and that the structure generation engine, which combines a Monte Carlo parallel tempering algorithm with an efficient lattice energy minimiser, was working effectively. For the three compounds for which the experimental crystal structures did not correspond to the lowest energy structures found, the method for calculating the lattice energy needs to be further refined or there may be other polymorphs that have not yet been found experimentally.
Anion‐Templated Supramolecular C3 Assembly for Efficient Inclusion of Charge‐Dispersed Anions into Hydrogen‐Bonded Networks
Authors: Užarević Krunoslav , Đilović Ivica , Bregović Nikola , Tomišić Vladislav , Matković‐Čalogović Dubravka , Cindrić Marina
Published: August 2011

The binding properties and conformational adaptability of a known nitrate/sulfate receptor N,N′‐3‐azapentane‐1,5‐bis[3‐(1‐aminoethylidene)‐6‐methyl‐3H‐pyran‐2,4‐dione] (L) toward various charge‐dispersed monoanions (HSO3−, ClO4−, IO4−, PF6−, and SbF6−) are considered. These anions template the folding of three HL+ species through a self‐assembly process into a new hollow supramolecular trication. During the self‐assembly, all strong hydrogen‐bond donors of the podand become coordinatively saturated by interactions with the oxo functionalities from other HL+ molecules. In that way, only the weak hydrogen‐bond‐donating groups in the exterior part of the receptor are accessible for anion binding. The investigated anions are accommodated in the hydrophobic pockets of the isomorphous hydrogen‐bonded frameworks, which serve as a basis for selective crystallization from the highly competitive anion/solvent systems. This behavior is discussed in terms of size and geometry of the anions as well as the receptor’s coordination capabilities to provide the most favorable surroundings for guest inclusion both in solution and in the solid state.
A Facile “Dispersion–Decomposition” Route to Metal Sulfide Nanocrystals
Authors: Zhuang Zhongbin , Lu Xiaotang , Peng Qing , Li Yadong
Published: August 2011

In this paper, we demonstrate a simple and general “dispersion–decomposition” approach to the synthesis of metal sulfide nanocrystals with the assistance of alkylthiol. This is a direct heating process without precursor injection. By using inorganic metal salts and alkylthiol as the raw materials, high‐quality Ag2S, Cu2S, PbS, Ni3S4, CdS, and ZnS nanocrystals were successfully synthesized. The mechanism study shows that the reaction undergoes two steps. A key intermediate compound, metal thiolate, is generated first. It melts and disperses into the solvent at a relatively low temperature, and then it decomposes into metal sulfide as a single precursor upon heating. This method avoids using toxic phosphine agent and injection during the reaction process. The size and shape of the nanocrystal can be also controlled by the concentration of the reactant and ligands. Furthermore, the optical properties and assembly of the nanocrystals have also been studied. This report provides a facile, direct‐heating “dispersion–decomposition” approach to synthesize metal sulfides nanocrystals that has potential for future large‐scale synthesis.
L‐Proline/CoCl2‐Catalyzed Highly Diastereo‐ and Enantioselective Direct Aldol Reactions
Authors: Karmakar Ananta , Maji Tapan , Wittmann Sebastian , Reiser Oliver
Published: August 2011

The CoCl2/L‐proline (1:2) system was found to be an excellent catalyst for direct aldol reactions. Excellent yields (up to 93 %) and a significant improvement in diastereoselectivity (anti/syn up to 45:1) as well as enantioselectivity (up to more than 99 % ee) compared with using proline as the sole catalyst were observed. This catalyst system was successfully applied to both cyclic and acyclic ketones in combination with aromatic and aliphatic aldehydes. In situ chelation of CoCl2 and proline (1:2) is proposed to promote the reaction through a six‐membered Zimmermann–Traxler type transition state involving the positioning of proline‐enamine and the aldehyde through chelation to CoII.
Total Synthesis of 7‐Ethyl‐10‐hydroxycamptothecin (SN38) and its Application to the Development of C18‐Functionalized Camptothecin Derivatives
Authors: Yao Yuan‐Shan , Liu Jia‐Li , Xi Jie , Miu Bukeyan , Liu Guai‐Sai , Wang Shaozhong , Meng Linghua , Yao Zhu‐Jun
Published: August 2011

A new chemical synthesis of SN38, the active metabolite of the camptothecin prodrug irinotecan, has been achieved in 12 steps from simple, commercially available starting materials. A mild and efficient FeCl3‐catalyzed Friedländer condensation was successfully applied to construct the AB ring system. Functionalization of the C ring was accomplished by a vinylogous Mukaiyama reaction of an in situ generated N‐acyliminium intermediate with a silyl enol ether. An intramolecular oxa Diels–Alder reaction efficiently constructed the D and E rings in one step. Successive asymmetric dihydroxylation and I2‐based hemiacetal oxidation furnished the stereochemistry of SN38 with high enantiopurity. Utilizing the ABC‐ring intermediate and a functionalized silyl enol ether permitted the synthesis of a number of new C18‐functionalized SN38 derivatives. Several of the novel SN38 derivatives that bore a C10 methoxy group were found to exhibit comparable or more potent inhibitory activity against the proliferation of cancer cells relative to SN38.
Modeling solvent effects on chiroptical properties
Authors: Mennucci Benedetta , Cappelli Chiara , Cammi Roberto , Tomasi Jacopo
Published: August 2011

In this article, the most advanced extensions of solvation models to chiroptical properties of solvated systems will be reviewed. The main aspects determining the complex phenomenon of solvation will be first discussed in terms of the physical interactions beyond them and successively translated in a computational language introducing the specific models. A particular attention will be devoted to the family of solvation models which couple a quantum‐mechanical description of the molecular solute and a continuum description of the solvent. The theoretical analysis will be supported with examples of applications showing the potentialities of the models and their accuracy in capturing the essence of solvent effects on optically active molecules. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Mono‐ and bis‐quinidine organocatalysts in the asymmetric methanolysis of cis‐1,2,3,6‐tetrahydrophthalic anhydride: A conformational and mechanistic NMR study
Authors: Balzano Federica , Jumde Ravindra P. , Mandoli Alessandro , MASI SOFIA , PINI DARIO , UCCELLO‐BARRETTA GLORIA
Published: August 2011

The enantioselective organocatalytic methanolysis of cis‐1,2,3,6‐tetrahydrophthalic anhydride mediated by quinidine derivatives with pyridazine or anthraquinone core was investigated, carrying out a detailed nuclear magnetic resonance study of the conformational preferences of the alkaloid catalysts in the pure solvent and in the presence of the reaction substrates and products. No significant interaction between the meso‐anhydride and the alkaloid derivatives was detected. In contrast, evidence for a considerable influence of the alcohol reactant on the conformational state of some of the chiral organocatalysts could be obtained, which lends support to the hypothesis of general‐base catalysis mechanism, as opposed to the nuclephilic one. The catalytic properties of the studied derivatives showed no obvious correlation with their conformational prevalence in the resting state, suggesting that the alkaloid 9‐O substituent should have a more active role than merely enforcing the chiral fragments to adopt a preferential reactive conformation. A strong enantioselective interaction between the enantiomers of the hemiester product and the alkaloid derivatives was also observed, leading to the conclusion that in the actual reaction conditions a relatively large fraction of the latter is in the protonated form. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Comparison of mid‐infrared Fourier transform vibrational circular dichroism measurements with single and dual polarization modulations
Authors: Polavarapu Prasad L. , Shanmugam Ganesh
Published: August 2011

Fourier transform infrared vibrational circular dichroism (FTIR‐VCD) measurements have gone through major advances in the last decade. A major thrust in these advances was to find ways that can minimize the VCD spectral artifacts and obtain the VCD signals at enhanced signal quality. However, all these advances are not incorporated in FTIR‐VCD instruments manufactured by some commercial manufacturers. In this article, we compare the measurements obtained with single and dual polarization modulations to seek the attention of the users of single polarization modulation method in minimizing the artifacts in such measurements. We also report that the VCD spectrum of a home‐made collagen film can serve as a simple and convenient sample for routine verification of the correct functioning of the VCD spectrometers. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Stereodivergent synthesis of diastereoisomeric carba analogs of glycal‐derived vinyl epoxides: A new access to carbasugars
Authors: Frau Ileana , Bussolo Valeria DI , Favero Lucilla , Pineschi Mauro , Crotti Paolo
Published: August 2011

A convenient method for the stereoselective synthesis of diasteroisomeric vinyl epoxides (−)‐2α and (−)‐2β, the carba analogs of D‐galactal and D‐allal‐derived vinyl epoxides 1αand 1β, has been elaborated starting from tri‐O‐acetyl‐D‐glucal. The key step of this synthesis is an application of the known Claisen thermal rearrangement of a glucal derivative, the vinyl allyl ether (+)‐3b, which allows to switch the glycal structure into the corresponding carba analog scaffold. Epoxides (−)‐2α and (−)‐2β derive from the same synthetic intermediate, the trans diol (+)‐5. Chirality, 2011. © 2011 Wiley‐Liss, Inc.
Actin‐depolymerizing factor homology domain: A conserved fold performing diverse roles in cytoskeletal dynamics
Authors: Poukkula Minna , Kremneva Elena , Serlachius Martina , Lappalainen Pekka
Published: August 2011

Actin filaments form contractile and protrusive structures that play central roles in many processes such as cell migration, morphogenesis, endocytosis, and cytokinesis. During these processes, the dynamics of the actin filaments are precisely regulated by a large array of actin‐binding proteins. The actin‐depolymerizing factor homology (ADF‐H) domain is a structurally conserved protein motif, which promotes cytoskeletal dynamics by interacting with monomeric and/or filamentous actin, and with the Arp2/3 complex. Despite their structural homology, the five classes of ADF‐H domain proteins display distinct biochemical activities and cellular roles, only parts of which are currently understood. ADF/cofilin promotes disassembly of aged actin filaments, whereas twinfilin inhibits actin filament assembly via sequestering actin monomers and interacting with filament barbed ends. GMF does not interact with actin, but instead binds Arp2/3 complex and promotes dissociation of Arp2/3‐mediated filament branches. Abp1 and drebrin are multidomain proteins that interact with actin filaments and regulate the activities of other proteins during various actin‐dependent processes. The exact function of coactosin is currently incompletely understood. In this review article, we discuss the biochemical functions, cellular roles, and regulation of the five groups of ADF‐H domain proteins. © 2011 Wiley‐Liss, Inc.
Low expression and secretion of circulating soluble CTLA‐4 in peripheral blood mononuclear cells and sera from type 1 diabetic children
Authors: Rydén Anna , Bolmeson Caroline , Jonson Carl‐Oscar , Cilio Corrado M. , Faresjö Maria
Published: August 2011

Background

High levels of soluble cytotoxic T‐lymphocyte antigen 4 (soluble CTLA‐4), an alternative splice form of the regulatory T‐cell (Treg) associated CTLA‐4 gene, have been associated with type 1 diabetes (T1D) and other autoimmune diseases, such as Grave's disease and myasthenia gravis. At the same time, studies have shown soluble CTLA‐4 to inhibit T‐cell activation through B7 binding. This study aimed to investigate the role of soluble CTLA‐4 in relation to full‐length CTLA‐4 and other Treg‐associated markers in T1D children and in individuals with high or low risk of developing the disease.

Methods

T1D children were studied at 4 days, 1 and 2 years after diagnosis in comparison to individuals with high or low risk of developing the disease. Isolated peripheral blood mononuclear cells were stimulated with the T1D‐associated glutamic acid decarboxylase 65 and phytohaemagglutinin. Subsequently, soluble CTLA‐4, full‐length CTLA‐4, FOXP3 and TGF‐β mRNA transcription were quantified and protein concentrations of soluble CTLA‐4 were measured in culture supernatant and sera.

Results and Conclusions

Low protein concentrations of circulating soluble CTLA‐4 and a positive correlation between soluble CTLA‐4 mRNA and protein were seen in T1D, in parallel with a negative correlation in healthy subjects. Further, low levels of mitogen‐induced soluble CTLA‐4 were accompanied by low C‐peptide levels. Interestingly, low mitogen‐induced soluble CTLA‐4 mRNA and low TGF‐β mRNA expression were seen in high risk individuals, suggesting an alteration in activation and down‐regulating immune mechanisms during the pre‐diabetic phase. Copyright © 2011 John Wiley & Sons, Ltd.
Skin fibroblasts as a tool for identifying the risk of nephropathy in the type 1 diabetic population
Authors: Millioni Renato , Puricelli Lucia , Iori Elisabetta , Trevisan Roberto , Tessari Paolo
Published: August 2011

Human fibroblasts in culture have been employed as an in vitro system to investigate some pathophysiological mechanisms of diabetes mellitus also associated with the development of diabetic nephropathy. In fact, there is increasing evidence that genetic factors either convey the risk of, or protect from, diabetic nephropathy and that the expression profiles and/or the behaviour of the cultured skin fibroblasts from type 1 diabetic patients could reflect these genetic influences. On the other hand, alterations could be attributable not only to changes in DNA sequence, but also to epigenetic factors. Our aim is to make a critical overview of the studies involving primary cultures of skin fibroblasts as tools to investigate the pathophysiology of diabetic nephropathy performed until now in this area. Cultured skin fibroblasts could be useful not only for the identification of patients at risk of developing diabetic renal disease, but also for a better understanding of the complex multifactorial mechanisms leading to the long‐term complications in diabetes. Copyright © 2011 John Wiley & Sons, Ltd.
Strategies for insulin initiation: insights from the French LIGHT observational study
Authors: Vergès Bruno , Brun Jean Marcel , Tawil Camille , Alexandre Bertrand , Kerlan Véronique
Published: August 2011

Background

The progressive nature of type 2 diabetes necessitates exogenous insulin use for most patients; basal insulin plus oral anti‐diabetes drugs (OADs) is a well‐validated way to facilitate insulin initiation. The primary aim of this study was to explore insulin initiation strategies and outcomes for patients using insulin detemir or glargine plus oral anti‐diabetes drugs.

Methods

LIGHT was a 3‐month, longitudinal observational study conducted across 761 French centres in insulin‐naïve type 2 diabetes patients managed under routine clinical care conditions, in either primary or secondary care. Endpoints included changes in HbA1c, fasting plasma glucose (FPG), rate of hypoglycaemia, weight, and adverse events.

Results

Most physicians initiated a basal analogue to improve glycaemic control (97%), with many delaying beginning treatment for several months (9 ± 9.0 months for general practitioners, 10.2 ± 16.2 months for specialists). Most patients continued oral anti‐diabetes drug therapy (95%) and lifestyle measures (92%), with 2–3 blood glucose readings per day and follow‐up telephone calls for dose optimization. Mean change in HbA1c from baseline was − 1.3%, and − 3.1 mmol/L for fasting plasma glucose (both p < 0.0001). Hypoglycaemia increased from 1.4 to 5.6 events/patient/year (p < 0.0001), and weight decreased on average by 0.5 kg with detemir, with no change in glargine. Most patients (93%) reported being satisfied or very satisfied with their insulin.

Conclusions

Insulin initiation with detemir or glargine can be successfully managed in both primary and secondary care; the benefits of basal analogues (once‐daily dosing, low rates of hypoglycaemia compared with neutral protamine Hagedorn) may have contributed to patient acceptance of the regimen. Copyright © 2012 John Wiley & Sons, Ltd.
Interfacial Electron Transfer Dynamics of Two Newly Synthesized Catecholate Bound RuII Polypyridyl‐Based Sensitizers on TiO2 Nanoparticle Surface – A Femtosecond Pump Probe Spectroscopic Study
Authors: Banerjee Tanmay , Rawalekar Sachin , Das Amitava , Ghosh Hirendra N.
Published: August 2011

Two new catecholate‐bound RuII–polypyridine based sensitizers, (2,2′‐bipyridine){ethyl 3‐(4‐hydroxyphenyl)‐2‐[(4′‐methyl‐2,2′‐bipyridinyl‐4‐carbonyl)amino]propionate}{4‐[2‐(4′‐methyl‐2,2′‐bipyridinyl‐4‐yl)vinyl]benzene‐1,2‐diol)}ruthenium(II) hexafluorophosphate (5) and [(2,2′‐bipyridine)‐(4‐2,2′‐bipyridinyl‐4‐yl‐phenol)‐(4‐{2‐(4′‐methyl‐2,2′‐bipyridinyl‐4‐yl)vinyl}benzene‐1,2‐diol)]ruthenium(II) hexafluorophosphate (6) with secondary electron‐donating groups (tyrosine and phenol, respectively) were synthesized and characterized. Steady‐state optical absorption and emission studies confirm strong coupling between the sensitizers and TiO2 nanoparticles. Femtosecond visible transient absorption spectroscopy has been employed to study interfacial electron transfer (IET) dynamics in the dye–nanoparticle systems to explore the influence of the secondary electron‐donating groups on IET dynamics. Electron injection into the conduction band of nanoparticulate TiO2 has been confirmed by detection of the conduction band electrons in TiO2 ([e–]TiO2CB) and radical cation of the adsorbed dye (D·+) in real time monitored by transient absorption spectroscopy. A single exponential and pulse‐width limited (< 100 fs) electron injection has been observed. Back electron transfer (BET) dynamics have been studied by monitoring the decay kinetics of the injected electron in the conduction band of TiO2 and by the recovery of the ground state bleach. BET dynamics in dye–TiO2 systems for complexes 5 and 6 have been compared with those of [bis(2,2′‐bpy)‐(4‐{2‐(4′‐methyl‐2,2′‐bipyridinyl‐4‐yl)vinyl}benzene‐1,2‐diol)]ruthenium(II) hexafluorophosphate (7), which does not have a secondary electron‐donating group.
A novel process for extraction of tea oil from Camellia oleifera seed kernels by combination of microwave puffing and aqueous enzymatic oil extraction
Authors: Zhang Wei‐guo , Zhang De‐cheng , Chen Xiao‐yuan
Published: August 2011

The objective of this study was to extract the oil from Camellia oleifera seed kernels by aqueous enzymatic oil extraction (AEOE). We describe a novel process for extraction of tea oil preceded by tea saponin extraction from C. oleifera seed kernels. The extraction efficiency obtained with microwave‐assisted extraction (MAE) is very high, which the recovery yield is up to 83% in 30 s and the saponins in camellia seed kernels can be completely removed by the second MAE. Moreover, an important step in the process development has been the pretreatment by microwave puffing of camellia seed kernel residues followed by AEOE increased oil extraction yield from 53% to 95%, which will is comparable to hexane oil extraction yields from plant materials.
Redox Properties and Cytotoxicity of Synthetic Isomeric Mitochondriotropic Derivatives of the Natural Polyphenol Quercetin
Authors: Mattarei Andrea , Sassi Nicola , Durante Christian , Biasutto Lucia , Sandonà Giancarlo , Marotta Ester , Garbisa Spiridione , Gennaro Armando , Paradisi Cristina , Zoratti Mario
Published: August 2011

Mitochondria‐targeted redox‐active polyphenol derivatives are being developed to affect redox processes in the organelles and as tools either to protect cells from oxidative damage or to precipitate their death. The properties of such compounds may be altered by substituents introduced to enhance mitochondrial delivery. Accordingly, we have characterized the redox behaviour of two isomeric mitochondriotropic quercetin‐based compounds, 3O‐ and 7O‐[4‐triphenylphosphonio)butyl]quercetin iodide. In both cyclic voltammetric determinations of the oxidation potential and in 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) radical scavenging assays, the 7‐substituted isomer behaved much like quercetin itself, whereas the 3‐substituted isomer was less reactive. Low μM concentrations of either compound increased superoxide radical anion formation in cultured cells; both compounds were also cytotoxic. The 7‐substituted derivative proved to be more active in both types of assays, thus emerging as the isomer of choice for further bioactivity studies and in efforts to understand the link between redox properties, pro‐oxidant behaviour and cytotoxicity.
First Synthesis of Medium‐Sized Ring Allenyl Lactams
Authors: Perscheid Moritz , Schollmeyer Dieter , Nubbemeyer Udo
Published: August 2011

Medium‐sized lactams bearing an axially chiral allene unit have been synthesized by using an aza‐ketene Claisen rearrangement. Starting from 2‐alkynylpiperidines or 2‐alkynylazepines, ring enlargement enabled the highly diastereoselective formation of 10‐ or 11‐membered lactams with a 4,5‐allene subunit. X‐ray analysis of the allenylacezinone showed the presence of a strained cumulated olefin system with a defined arrangement of the functional groups. The cyclic allenes were found to be stable upon heating up to 50 °C.
One‐Pot Synthesis of Fused Benzo[c]carbazoles by Photochemical Intramolecular Annulation of 3‐Acyl‐2‐haloindoles with Tethered Styrenes
Authors: Lu Shen‐Ci , Wei Shi‐Chao , Wang Wei‐Xia , Zhang Wei , Tu Zhi‐Feng
Published: August 2011

An efficient procedure for the synthesis of fused benzo[c]carbazoles has been achieved in moderate to high yields by the one‐pot photochemical annulation of 3‐acyl‐2‐haloindoles with tethered styrenes by photoinduced electron‐transfer coupling, electrocyclic reactions, and deacylative aromatization in the presence of pyridine. Fused furo[2,3‐c]carbazoles were also synthesized under the same conditions. 5,6‐Dihydrobenzo[c]pyrrolo[1,2,3‐lm]carbazoles were oxidized by DDQ to afford aromatic benzo[c]pyrrolo[1,2,3‐lm]carbazole products in moderate to high yields.
Barcoding ofGiardia duodenalisisolates and derived lines from an established cryobank by a mutation scanning‐based approach
Authors: Nolan Matthew J. , Jex Aaron R. , Upcroft Jacqui A. , Upcroft Peter , Gasser Robin B.
Published: August 2011

We barcoded 25 in vitro isolates (representing 92 samples) ofGiardia duodenalisfrom humans and other animals, which have been assembled by the Upcroft team at the Queensland Institute of Medical Research over a period of almost three decades. We used mutation scanning‐coupled sequencing of loci in the triosephosphate isomerase, glutamate dehydrogenase and β‐giardin genes, combined with phylogenetic analysis, to genetically characterise them. Specifically, the isolates (n=14) ofG.duodenalisfrom humans from Australia (AD113; BRIS/83/HEPU/106; BRIS/87/HEPU/713; BRIS/89/HEPU/1003; BRIS/92/HEPU/1541; BRIS/92/HEPU/1590; BRIS/92/HEPU/2443; BRIS/93/HEPU/1706), Malaysia (KL/92/IMR/1106) and Afghanistan (WB), a cat from Australia (BAC2), a sheep from Canada (OAS1) and a sulphur‐crested cockatoo from Australia (BRIS/95/HEPU/2041) represented assemblage A (sub‐assemblage AI‐1, AI‐2 or AII‐2); isolates (n=10) from humans from Australia (BRIS/91/HEPU/1279; BRIS/92/HEPU/2342; BRIS/92/HEPU/2348; BRIS/93/HEPU/1638; BRIS/93/HEPU/1653; BRIS/93/HEPU/1705; BRIS/93/HEPU/1718; BRIS/93/HEPU/1727), Papua New Guinea (BRIS/92/HEPU/1487) and Canada (H7) represented assemblage B (sub‐assemblage BIV) and an isolate from cattle from Australia (BRIS/92/HEPU/1709) had a match to assemblage E. Isolate BRIS/90/HEPU/1229 from a human from Australia was shown to represent a mixed population of assemblages A and B. These barcoded isolates (including stocks and derived lines) now allow direct comparisons of experimental data among laboratories and represent a massive resource for transcriptomic, proteomic, metabolic and functional genomic studies using advanced molecular technologies. (Nucleotide sequences reported in this paper are available in the GenBank database under accession nos. JN204442–JN204461.)
Perlecan domain V modulates astrogliosis In vitro and after focal cerebral ischemia through multiple receptors and increased nerve growth factor release
Authors: Al‐Ahmad Abraham J. , Lee Boyeon , Saini Maxim , Bix Gregory J.
Published: August 2011

Astrogliosis constitutes part of the central nervous system's physiological response to injury. Considered for decades to be a major challenge for brain repair, recent studies have highlighted it as a promoter of such repair mechanisms. Recently, our group demonstrated the ability of perlecan domain V (DV) to be a novel potential stroke therapy by its neuroprotective effects. However, the potential for DV to modulate astrogliosis has not been investigated. The aim of this study is to better understand the relevance of DV to astrogliosis using both in vitro and in vivo rodent models. Notably, under basal conditions, astrocytes express all three DV receptors described in the literature: integrin α2β1, α5β1, and α‐dystroglycan (αDG). DV promoted astrocyte cell adhesion, cell migration as well as astrocyte stellation. Moreover, DV induced nerve growth factor (NGF) secretion through a αDG‐ and ERK‐dependent pathway. In contrast, α2β1 or α5β1 mediated DV antiproliferative effects in astrocytes. NGF production after DV treatment acted as a strong anti‐proliferative agent. Another remarkable effect of DV was that it decreased several markers of astrogliosis such as glial fibrillary acidic protein (GFAP), neurocan and phosphacan both in vitro and in vivo, suggesting the role of DV as a potential modulator of postinjury during late astrogliosis, and eventually the onset of glial scarring. Taken together, our study demonstrates the ability of DV to modulate key events of astrogliosis by promoting early astrogliosis and inhibiting glial scar formation, suggesting an additional therapeutic benefit of DV for recovery from stroke. © 2011 Wiley‐Liss, Inc.
Translational regulation mechanisms of aquaporin‐4 supramolecular organization in astrocytes
Authors: Pisani Francesco , Rossi Andrea , Nicchia Grazia Paola , Svelto Maria , Frigeri Antonio
Published: August 2011

The two predominant isoforms of Aquaporin‐4 (AQP4), AQP4‐M23 and AQP4‐M1, assemble in the plasma membrane to form supramolecular structures called Orthogonal Array of Particles (OAPs) whose dimension is tightly associated to the M1/M23 ratio. Here, we explore translational regulation contribution to M1/M23 expression in primary cultures of rat astrocytes, and analyze the role of M1 mRNA 5′untranslated region (5′UTR) in this mechanism. Using isoform‐specific RNAi we found that in rat astrocytes primary cultures a large proportion of M23 protein derives from M1 mRNA translation. Furthermore, site‐specific mutagenesis of the 5′UTR sequence of AQP4‐M1 mRNA indicates that a multiple‐site leaky scanning mechanism, an out‐of‐frame upstream ORF (uORF), and a reinitiation mechanism are able to modulate the M1/M23 ratio and consequently, OAPs formation. These mechanisms are likely to be shared by different species, including human, and they can also be assumed to play a role in those pathophysiological situations where the organization of AQP4 in supramolecular structures (OAPs) is involved. Finally, we report that, when transfected in Hela cells, the longer rat AQP4 isoform, called Mz, which is not present in human impairs OAPs formation. © 2011 Wiley‐Liss, Inc.
Relationship between serum thyroglobulin and 18FDG‐PET/CT in 131I‐negative differentiated thyroid carcinomas
Authors: Giovanella Luca , Ceriani Luca , De Palma Diego , Suriano Sergio , Castellani Massimo , Verburg Frederik A.
Published: August 2011

Background

The purpose of this study was to assess the relationship between [18F]‐fluorodeoxyglucose (18FDG)‐positron emission tomography/CT (18FDG‐PET/CT) and serum thyroglobulin (Tg) in patients with recurrent differentiated thyroid carcinoma (DTC).

Methods

Forty‐two patients with recurrent DTC and negative Tg antibodies were included in the study. All patients underwent 131I therapy due to an increasing serum Tg with a corresponding negative 131I posttreatment whole body scan. The 18FDG‐PET/CT scans were then performed on all patients, serum Tg was measured concurrently, and respective results were compared.

Results

Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), and accuracy of the 18FDG‐PET/CT examination were 93%, 84%, 93%, 84%, and 90%, respectively. The sensitivity of 18FDG‐PET/CT significantly increased in patients with serum Tg levels ≥4.6 ng/mL (96%) in comparison with patients having lower levels (25%; p < .001). Nonetheless, 3 of 27 patients (11%) with a true‐positive 18FDG‐PET/CT still had a Tg <4.6 ng/mL.

Conclusion

Although 18FDG‐PET/CT scans are more likely to be positive with pretest Tg levels ≥4.6 ng/mL, 11% of patients with DTC with a lower serum Tg level will still have a positive scan. Our findings are in contrast with the American Thyroid Association (ATA) guidelines, which only recommend to perform 18FDG‐PET/CT in patients with Tg levels >10 ng/mL. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Cancer stem cells in head and neck squamous cell carcinoma: A review of current knowledge and future applications
Authors: Bhaijee Feriyl , Pepper Dominique J. , Pitman Karen T. , Bell Diana
Published: August 2011

Head and neck squamous cell carcinoma (HNSCC) is a major cause of morbidity and mortality, and the alleviation thereof requires greater understanding of the pathobiologic behavior of HNSCC. Although the existence of cancer stem cells (CSCs) in most solid tumors has not been formally proven, application of the CSC concept has certainly enhanced understanding of HNSCC heterogeneity and progression. Recent data support the role of ALDH1+CD44+ CSC in HNSCC, since the implantation of a few ALDH1+CD44+ cells consistently gives rise to tumors that can be serially passaged in vivo. In addition to CSC biomarkers, recent explorations of CSC signaling pathways, gene expression, and localization in HNSCC carry significant clinical and therapeutic implications. Identification and characterization of CSC populations that regulate HNSCC growth, metastasis, and treatment resistance will facilitate development of novel diagnostic, therapeutic, and prognostic strategies. Furthermore, advances in multimodal imaging and nanotechnology, in conjunction with CSC models, may better elucidate the regulatory mechanisms that govern CSC biology in vivo, as well as develop platforms for targeted theragnostics. It is hoped that the promising applications of the CSC model in HNSCC will eventually alleviate the morbidity and mortality of this pervasive disease. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Treatment‐induced changes in vocal cord mobility and subsequent local recurrence after organ preservation therapy for laryngeal carcinoma
Authors: Lee Walter T. , Yoo David S. , Puscas Liana , Witsell David , M. Cohen Seth , R. Fisher Samuel , Scher Richard , Broadwater Gloria , Ready Neal , R. Brizel David , Esclamado Ramon M.
Published: August 2011

Background

As multidisciplinary cancer treatment evolves, strategies to identify patients needing early resection/salvage are necessary. Some have suggested that vocal cord function after organ‐preservation treatment may be an indicator.

Methods

A retrospective review was performed of patients presenting with fixed or impaired vocal cord function at a tertiary center. Local recurrence rates were examined in patients with and without improved/normal mobilization after treatment.

Results

Sixty‐nine patients met the inclusion criteria, with 35 patients having vocal cord fixation and 34 patients with impaired mobility. After treatment, 44 patients had normalization of vocal cord function, while 25 patients did not, with 2‐year local control rates of 70% and 77%, p = .23, respectively. No difference in local control was found between patients with normalized/improved cord function (n = 53) and those who remained the same/worsened (n = 16; p = .81).

Conclusion

Therapy‐induced changes in vocal cord mobility did not correlate with local recurrence. Other criteria are needed to identify patients most likely to benefit from early surgical resection/salvage after organ preservation. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Postoperative radiation therapy for small, low‐/intermediate‐grade parotid tumors with close and/or positive surgical margins
Authors: Richter Samuel M. , Friedmann Patricia , Mourad Waleed F. , Hu Kenneth S. , Persky Mark S. , Harrison Louis B.
Published: August 2011

Background

Patients with small, low‐/intermediate‐risk parotid cancers, treated with surgery, and who have the single prognostic factor of close and/or positive margins, constitute an unusual subset. This study evaluates local control and morbidity associated with postoperative radiation therapy for low/intermediate grade parotid cancer in these patients.

Methods

Between 1999 and 2006, 17 patients underwent postoperative radiation therapy at Beth Israel Medical Center for acinic cell carcinoma or low‐intermediate‐grade mucoepidermoid carcinoma of the parotid with close/positive margins. Pathology, treatment, and follow‐up data were retrospectively analyzed for morbidity and local control. Two‐ and 5‐year estimates of survival outcomes were performed followed by an analysis of complications.

Results

There were no local failures and no significant long‐term complications.

Conclusions

Patients with small, low‐risk cancer of the parotid gland have excellent local control and low treatment‐related morbidity when receiving postoperative radiation therapy for positive or close margins of resection. © 2011 Wiley Periodicals, Inc. Head Neck, 2012
Non‐integrating lentiviral vectors for specific killing of Epstein–Barr virus nuclear antigen 1‐positive B cell lymphoma cells
Authors: Flynn Ryan P. , Zacharias Jeana , Zhou Xianzheng , Cannon Mark L. , Philpott Nicola J.
Published: August 2011

Background

Epstein–Barr virus (EBV) causes a range of life‐threatening B‐lymphocyte malignancies but, despite the use of various strategies, treatment remains problematic.

Methods

In the present study, we developed a non‐integrating lentiviral vector (NILV) that mediates specific killing of EBV nuclear antigen 1 (EBNA1)‐expressing cells with minimal toxicity to EBNA1‐negative cells. The EBV family of repeats (FR) was cloned intok the NILV genome upstream of various transgenes.

Results

The presence of the FR in the NILV genome induced transcriptional up‐regulation and prolonged the expression of a transgene specifically in EBNA1‐positive B cells. Transgene expression from an FR‐containing NILV was also prolonged in EBV‐transformed cells compared to an FR‐negative NILV. We found that the delivery of an FR‐containing NILV encoding herpes simplex virus 1 thymidine kinase (TK) lead to the killing of more than 99% of EBNA1‐positive B cells with minimal toxicity to EBNA1‐negative cells in the presence of gancyclovir. EBNA1‐positive cells were not killed by an FR‐negative vector containing the TK gene. An FR‐TK‐containing NILV also specifically killed EBNA1‐containing cells in a mixed population of EBNA1‐positive and EBNA1‐negative cells, thus confirming that NILV‐FR‐TK‐mediated killing is specific for EBNA1‐expressing cells.

Conclusions

Transgene expression from our NILVs is both EBNA1‐specific and dependent upon the presence of the FR. The results obtained in the present study indicate that NILVs have potential use in the treatment of EBV‐associated B cell malignancies. Copyright © 2011 John Wiley & Sons, Ltd.
Is extreme Arctic sea ice anomaly in 2007 a key contributor to severe January 2008 snowstorm in China?
Authors: Na Liu , Jiping Liu , Zhanhai Zhang , Hongxia Chen , Mirong Song
Published: August 2011

We conduct numerical experiments with an atmospheric general circulation model to answer the question whether the extreme Arctic sea ice anomaly in 2007 contributed to the severe January 2008 snowstorm in China. Results show that the record low Arctic sea ice in September 2007, and follow‐up slow recovery of the Arctic sea ice in October and November 2007 could excite two stationary wave structures. One wave train propagates southeastward from the Barents/Kara Seas to central Asia, strengthening the Middle East Jet Stream (MEJS), and the other wave train propagates southward from central Arctic Ocean/eastern Siberia Sea to the mid‐latitude and subtropics of the north Pacific, weakening the East Asian Jet Stream (EAJS). The anomalous westerlies associated with the strengthening of the MEJS and the anomalous easterlies associated with the weakening of the EAJS form a strong convergence zone over central and southern China, providing favorable conditions for the severe January 2008 snowstorm. Copyright © 2011 Royal Meteorological Society
Guidelines of a Unified Approach for Product and Business Process Modeling in Complex Enterprise
Authors: Corallo Angelo , De Paolis Paolo , Ippoliti Monica , Lazoi Mariangela , Scalvenzi Massimo , Secundo Giustina
Published: August 2011

Purpose

Many differences exist between a generic process representation and the real flow of activities performed in relation to specific products/programs within an enterprise. The product life cycle modeling approach allows us to model the temporal flow of activities from conceptualization to disposal of specific product/program. In contrast, the business process modeling approach provides a general process perspective. The two views taken alone are not entirely satisfactory. This paper aims to propose a unified and integrated product–business process modeling approach, which overcomes the limitations inherent in adopting a single perspective, maintaining as much as possible, the essential characteristics and strengths of both modeling approaches.

Design/methodology/approach

The conceptual model of the proposed unified approach is based on the review of existing process and product modeling theories and on an inductive perspective emerging from the observation of the organizational practices in a number of Italian aerospace companies.

Findings

The proposed approach is expressed in eight guidelines, which describe a new unifying perspective to be adopted in different domains, which ensure that managers identify the assets and activities that are associated with each product that an organization creates. Constraints are also suggested. Some practical applications and examples using the software, aris (IDS Scheer, Saarland, Germany) are also provided based on actual practices in an aerospace company.

Originality/value

This paper describes a new unifying perspective for a combination of product/business process modeling view. Copyright © 2011 John Wiley & Sons, Ltd.
Present state of immunosuppressive therapy in liver transplant recipients
Authors: Wiesner Russell H. , Fung John J.
Published: August 2011

Key Points

1. Our increasing understanding of the signaling pathways and cellular interactions in transplant immunobiology has facilitated targeted strategies using novel immunosuppressive agents.

2. The pattern of immunosuppressive drug use in the United States continues to change, and the changes include the use of antibody induction therapy and the agents used in maintenance therapy.

3. The driving forces behind the development of new immunosuppressive regimens are the long-term complications of current immunosuppressive regimens (particularly renal dysfunction and metabolic disturbances).
Hepatocellular carcinoma: Agents and concepts for preventing recurrence after curative treatment
Authors: Schlitt Hans J. , Schnitzbauer Andreas A.
Published: August 2011

Key Points

1. Adjuvant/neoadjuvant chemotherapy.

2. Neoadjuvant transarterial chemoembolization.

3. Kinase inhibitors (eg, sorafenib).

4. Antiviral treatment.

5.Immunosuppressive treatment after liver transplantation.

6. Disseminated tumor cells: the basis for innovative treatment options?
Future prospects in immunosuppression for liver transplantation
Authors: Fung John J. , Bollinger Jessica E. , Miller Charles , Eghtesad Bijan
Published: August 2011

Key Points

1. Our increasing understanding of signaling pathways and cellular interactions in transplant immunobiology and the availability of novel immunosuppressive agents have facilitated targeted strategies.

2. The driving forces behind the development of new immunosuppressive regimens are the long-term complications of current immunosuppressive regimens (particularly renal dysfunction and metabolic disturbances).

3. By regulatory mandate, the requirement for the primary endpoint to be a composite of death, graft loss, and rejection remains intact; however, current and future clinical trials could incorporate key secondary endpoints that address renal and metabolic derangements.
Hot-topic debate on hepatitis C virus: The type of immunosuppression matters
Authors: Trotter James F.
Published: August 2011

Key Points

1. The treatment of rejection is an important factor associated with the severe recurrence of hepatitis C virus (HCV) after liver transplantation.

2. The effects of calcineurin inhibitors, corticosteroids, and mycophenolate mofetil on HCV recurrence are equivocal.

3. Cyclosporine is associated with a higher sustained virological response in patients treated for HCV.

4. Because insulin resistance and diabetes are associated with fibrosis in HCV-infected liver transplant recipients, the use of immunosuppressive agents without this side effect may slow the posttransplant disease progression.