bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the Role of Homogeneity When Controlling Single‐Leader Networks
Authors: Twu Philip , Egerstedt Magnus 
Published: September 2012

AbstractThis paper presents an approach to controlling agent positions in single‐leader networks to target points while explicitly taking agent homogeneity into account. When the capabilities of agents to accomplish tasks at each of the targets are identical, then the label of the target points may be permuted while still expressing the same intention. In single‐leader networks which are not completely controllable, such a permutation of the target points may at times move a target closer to the system's reachable subspace, thereby allowing the network to surpass the limitations on controllability when homogeneity is not considered explicitly. To fully exploit this property in homogeneous networks, it is then necessary to find the permutation of a target point which brings it closest to the reachable subspace. However, finding this optimal permutation is shown to be in general a non‐deterministic polynomial‐time (NP)‐hard problem. Specific network topologies are identified for when finding such an optimal permutation of a target point can be advantageous when controlling single‐leader networks. Moreover, an alternate view of the problem of finding optimal permutations is presented in which clustering‐based algorithms can be applied to find suboptimal solutions.
Pharmacokinetic and safety evaluation of the use of ciprofloxacin on an isoniazid‐rifampicin regimen in rabbits
Authors: Padilha Elias Carvalho , Pires Rodrigo Vieira , Filho Marco Antonio Ferraz Nogueira , de Pontes Machado Diego Vinicius , Baldan Helen Mariana , Davanço Marcelo Gomes , Campos Michel Leandro , Brunetti Iguatemy Lourenço , Peccinini Rosângela Gonçalves 
Published: September 2012

ABSTRACTThe combination of isoniazid (INH), rifampicin (RMP) and pyrazinamide (PYR) is used in the treatment of tuberculosis. Although this treatment is effective in most clinical cases, the side‐effects and the development of mycobacterium resistance have hindered its success. There is evidence that the combination of INH, RMP and ciprofloxacin (CIPRO) is useful in the treatment of tuberculosis. However, the influence of this drug combination on the hepatotoxicity of INH is unknown. In this study, the safety of combined INH, RMP and CIPRO was evaluated. Male albino rabbits (n = 20) were divided into four groups and subjected to multiple oral doses for 7 days according to the following treatments: water (group 1); 50 mg/kg INH (group 2); 50 mg/kg INH + 100 mg/kg RMP (group 3) and 50 mg/kg INH + 100 mg/kg RMP + 50 mg/kg CIPRO (group 4). Blood samples were taken before and after treatments for the determination of ALT, AST, ALP and bilirubin to assess hepatotoxicity. For pharmacokinetic analysis, serial blood samples were collected over 24 h on day 7 of treatment. Plasma concentrations of INH and acetylisoniazid (AcINH) were determined by HPLC. Biochemical parameters did not show any statistically significant differences between the groups that received the drug combinations. The pharmacokinetic profile of INH was also similar for both groups of combinations. These findings allow us to infer that the inclusion of CIPRO did not increase the risk of hepatotoxicity when compared with the classic combination of INH and RMP. Copyright © 2012 John Wiley & Sons, Ltd.
Spectroscopic study of the interaction between lycopene and bovine serum albumin
Authors: Rodríguez Galdón Beatriz , Pinto Corraliza Carmen , Cestero Carrillo Juan J. , Macías Laso Pedro 
Published: September 2012

ABSTRACTThe interaction of lycopene with bovine serum albumin (BSA) in aqueous solution was studied by fluorescence quenching, three‐dimensional fluorescence and circular dichroism spectroscopy. The data showed that the fluorescence of BSA was quenched by lycopene at different temperatures through a dynamic mechanism. The evaluation of three‐dimensional fluorescence spectra revealed a conformational modification of BSA induced by coupling with lycopene and an increase in protein diameter as a consequence of the ligand–protein interaction. Moreover, the information obtained from evaluation of the effect of lycopene on BSA conformation by circular dichroism strongly supported the existence of a slight unfolding of BSA induced by coupling to lycopene. Copyright © 2012 John Wiley & Sons, Ltd.
The activity of prolactin releasing peptide correlates with its helicity
Authors: DeLuca Stephanie H. , Rathmann Daniel , Beck‐Sickinger Annette G. , Meiler Jens 
Published: September 2012

AbstractThe prolactin releasing peptide (PrRP) is involved in regulating food intake and body weight homeostasis, but molecular details on the activation of the PrRP receptor remain unclear. C‐terminal segments of PrRP with 20 (PrRP20) and 13 (PrRP8‐20) amino acids, respectively, have been suggested to be fully active. The data presented herein indicate this is true for the wildtype receptor only; a 5‐10‐fold loss of activity was found for PrRP8‐20 compared to PrRP20 at two extracellular loop mutants of the receptor. To gain insight into the secondary structure of PrRP, we used CD spectroscopy performed in TFE and SDS. Additionally, previously reported NMR data, combined with ROSETTANMR, were employed to determine the structure of amidated PrRP20. The structural ensemble agrees with the spectroscopic data for the full‐length peptide, which exists in an equilibrium between α‐ and 310‐helix. We demonstrate that PrRP8‐20's reduced propensity to form an α‐helix correlates with its reduced biological activity on mutant receptors. Further, distinct amino acid replacements in PrRP significantly decrease affinity and activity but have no influence on the secondary structure of the peptide. We conclude that formation of a primarily α‐helical C‐terminal region of PrRP is critical for receptor activation. © 2012 Wiley Periodicals, Inc. Biopolymers 99: 273–281, 2013.
Mutation in Elongation Factor G Confers Resistance to the Antibiotic Argyrin in the Opportunistic Pathogen Pseudomonas aeruginosa
Authors: Bielecki Piotr , Lukat Peer , Hüsecken Kristina , Dötsch Andreas , Steinmetz Heinrich , Hartmann Rolf W. , Müller Rolf , Häussler Susanne 
Published: September 2012

AbstractThe natural myxobacterial product argyrin is a cyclic peptide exhibiting immunosuppressive activity as well as antibacterial activity directed against the highly intrinsically resistant opportunistic pathogen Pseudomonas aeruginosa. In this study, we used whole‐genome sequencing technology as a powerful tool to determine the mode of action of argyrin. Sequencing of argyrin‐resistant P. aeruginosa isolates selected in vitro uncovered six point mutations that distinguished the resistant mutants from their susceptible parental strain. All six mutations were localized within one gene: fusA1, which encodes for the elongation factor EF‐G. After the reintroduction of selected mutations into the susceptible wild type, the strain became resistant to argyrin. Surface plasmon resonance experiments confirmed the interaction of argyrin A with FusA1. Interestingly, EF‐G has been previously shown to be the target of the anti‐Staphylococcus antibiotic fusidic acid. Mapping of the mutations onto a structural model of EF‐G revealed that the mutations conveying resistance against argyrin were clustered within domain III on the side opposite to that involved in fusidic acid binding, thus indicating that argyrin exhibits a new mode of protein synthesis inhibition. Although no mutations causing argyrin resistance have been found in other genes of P. aeruginosa, analysis of the sequence identity in EF‐G and its correlation with argyrin resistance in different bacteria imply that additional factors such as uptake of argyrin play a role in the argyrin resistance of other organisms.
Transulnar catheterization in patients with ipsilateral radial artery occlusion
Authors: Kwan Tak W. , Ratcliffe Justin A. , Chaudhry Muhammad , Huang Yili , Wong Sally , Zhou Xuanjing , Pancholy Samir , Patel Tejas 
Published: September 2012

BackgroundThe transradial approach to percutaneous coronary intervention (PCI) has recently gained popularity among interventionalists. However, radial artery occlusion (RAO) limits the ability for repeat catheterization. In current practice, transulnar catheterization is thought to be a contraindication in patients with ipsilateral RAO.MethodsSeventeen consecutive patients undergoing transulnar catheterization and PCI were reviewed. Each of the patients had clinical follow‐up post‐procedure at days 1, 7, and 30.ResultsWe successfully performed 17 ulnar catheterizations in patients with ipsilateral RAO. All patents were subsequently found to have adequate collaterals from the anterior interosseous branch. One patient developed ulnar artery spasm and another patient developed a forearm hematoma. Overall, no patient suffered any ulnar nerve injury. The ulnar artery was patent both by palpation and by the presence of an adequate plethysmographic signal during follow‐up at days 1, 7, and 30. No patients developed with any signs or symptoms of hand ischemia during follow‐up.ConclusionIn patients with RAO, ipsilateral transulnar catheterization may not be an absolute contraindication. Our results suggest that extensive collaterals from the anterior interosseous artery may be the reason for protection against hand ischemia in the setting of RAO. © 2012 Wiley Periodicals, Inc.
Transcatheter access route options for treatment of degenerated mitral valve prosthesis with a balloon‐expandable biological valve
Authors: Schaefer Ulrich , Frerker Christian , Bader Ralf , Schmoeckel Michael , Busse Cord , Kuck Karl‐Heinz 
Published: September 2012

ObjectivesThere is an ongoing discussion if valve‐in‐valve implantations into failing mitral xenografts should be performed only via a transapical approach.BackgroundIn selected high‐risk patients, transcatheter valve implantation is an emerging therapy for degenerated mitral xenografts in need of repeated valve replacement.MethodsHere we describe three different strategies to treat a failing mitral biological prosthesis (Carpentier Edwards S.A.V) by implantation of a SAPIEN‐XT valve, which was performed in three different patients. As access site, a transjugular/transseptal approach, a transfemoral/transseptal approach, and a transapical approach were chosen.ResultsWith all three approaches, valve‐in‐valve implantation was successfully achieved. The acute hemodynamic effects were excellent and according to VARC there was no adverse event recorded during a 6 months follow‐up.ConclusionsFeasibility of all three approaches is demonstrated and might be taken into consideration for treatment in various patients. © 2012 Wiley Periodicals, Inc.
Three‐dimensional intravascular ultrasound evaluation of carina and plaque shift at the distal left main coronary artery bifurcation after treatment with a one‐stent cross‐over technique
Authors: Xiu Jiancheng , Choi So‐Yeon , Mintz Gary S. , Araki Hiroshi , Masuda Naoki , Morino Yoshihiro , Sonoda Shinjo , Tahk Seung Jea , Ochiai Masahiko , Maehara Akiko 
Published: September 2012

ObjectiveTo assess the geometrical changes in the distal left main coronary artery (LMCA), left anterior descending (LAD), and left circumflex (LCX) that occur after a distal LMCA lesion is treated using a one‐stent cross‐over strategy.BackgroundMorphological changes after stent implantation into distal LMCA lesions are not fully understood.MethodsWe used pre‐ and postintervention three‐dimensional intravascular ultrasound of both the LAD and LCX as well as of the LMCA to evaluate distal LMCA lesions after a 1‐stent cross‐over strategy. In 38 distal LMCA bifurcation lesions, cross‐sectional measurements were performed every 1 mm over a 5‐mm segment in the LAD and LCX distal to the carina and over the entire LMCA proximal to the carina.ResultsThe increase in lumen volume correlated with the increase in external elastic membrane volumes: R = 0.917, P < 0.001, in the LMCA and R = 0.785, P < 0.001, in the LAD with no decrease in plaque volume except at the distal end of the LMCA (P = 0.081) and at the LAD carina (P = 0.11). The LCX lumen area decreased significantly at the LCX carina from 5.9 ± 2.0 mm2 to 5.3 ± 1.9 mm2 (P < 0.01); however, the response was variable from a 4.0 mm2 decrease to a 1.8 mm2 increase in lumen area. While the change in LCX lumen area at the carina correlated with the change in vessel area (R = 0.791, P < 0.001), there was also a small increase in plaque area at the LCX carina from 6.4 ± 2.9 mm2 to 6.8 ± 2.9 mm2 (P < 0.01).ConclusionsLMCA bifurcation lumen changes after cross‐over single‐stent implantation were determined primarily by conformational changes in vessel geometry. © 2012 Wiley Periodicals, Inc.
Thermodynamic Analysis‐Based Improvement for the Boil‐off Gas Reliquefaction Process of Liquefied Ethylene Vessels
Authors: Li Y. , Jin G. , Zhong Z. 
Published: September 2012

AbstractA new optimization design of the boil‐off gas (BOG) reliquefaction process for liquefied ethylene (LEG) vessels is proposed in order to reduce the reliquefaction process energy cost and improve its cold exergy efficiency. The exergy loss of each component is calculated and the efficiency of the available energy utilization is evaluated on the basis of a detailed thermodynamic analysis. The exergy analysis results indicate that the exergy efficiency of the improved BOG reliquefaction process is about 19.0 % higher than that of the existing process, and the amount of refrigerant used in the improved process is reduced by about 44.9 % per hour. The power consumption could be decreased by 16 %. The circulation volumes of the refrigerant and BOG are both significantly reduced, thus lowering the equipment and operation costs of the BOG reliquefaction process.
Recent Advances in Microbial Fuel Cells Integrated with Sludge Treatment
Authors: Wang Z. , Mei X. , Ma J. , Wu Z. 
Published: September 2012

AbstractMicrobial fuel cells (MFCs), which can directly convert chemical energy in organic matters into electricity, have drawn a lot of attention in the past decades. Recently, MFCs have been integrated with waste‐activated sludge (WAS) treatment for recovering energy from WAS. Since 2004, a number of publications regarding this topic have been published. The recent advances in MFCs powered by WAS are critically reviewed. MFC reactor designs, MFC performances, and sludge degradation efficiencies are addressed based on the recent related publications. The challenges and corresponding enhancement measures of MFCs using WAS as fuel are also discussed.
The Remarkable Effect of the Manganese Ion with Dioxygen on the Stability of π‐Conjugated Radical Cations
Authors: El‐Agamey Ali , Fukuzumi Shunichi 
Published: September 2012

AbstractIn this paper, nanosecond laser flash photolysis has been used to investigate the influence of metal ions on the kinetics of radical cations of a range of carotenoids (astaxanthin (ASTA), canthaxanthin (CAN), and β‐carotene (β‐CAR)) and various electron donors (1,4‐diphenyl‐1,3‐butadiene (14DPB), 1,6‐diphenyl‐1,3,5‐hexatriene (16DPH), 4‐methoxy‐trans‐stilbene (4 MeOSt), andtrans‐stilbene (trans‐St)) in benzonitrile. Radical cations have been generated by means of photosensitized electron‐transfer (ET) using 1,4‐dicyanonaphthalene (14DCN) and biphenyl (BP). The kinetic decay of CAR.+shows a strong dependence on the identity of the examined metal ion. For example, whereas NaClO4has a weak effect on the kinetics of CAR.+, Ni(ClO4)2causes a strong retardation of the decay of CAR.+. It is also interesting to note that Mn2+, which is a biologically relevant metal ion, shows the strongest effect of all the investigated metal ions (e.g., in the presence of Mn2+ions, the half‐life (t1/2) of CAN.+(t1/2>90 ms) is more than three orders of magnitude higher than in the absence of the metal ions (t1/2≈16 μs)). Furthermore, the influence of metal‐ion and oxygen concentrations on the kinetics of CAR.+reveals their pronounced effect on the kinetic decay of CAR.+. However, these remarkable effects are greatly diminished if either oxygen or metal ions are removed from the investigated solutions. Therefore, it can be concluded that oxygen and metal ions interact cooperatively to induce the observed substantial effects on the stabilities of CAR.+. These results are the first direct observation of the major role of oxygen in the stabilization of radical cations, and they support the earlier mechanism proposed by Astruc et al. for the role of oxygen in the inhibition of cage reactions. On the basis of these results, the factors that affect the stability of radical cations are discussed and the mechanism that shows the role of oxygen and metal ions in the enhancement of radical‐cation stability is described.
Synthesis and Supramolecular Studies of Chiral Boronated Platinum(II) Complexes: Insights into the Molecular Recognition of Carboranes by β‐Cyclodextrin
Authors: Ching H. Y. Vincent , Clifford Sarah , Bhadbhade Mohan , Clarke Ronald J. , Rendina Louis M. 
Published: September 2012

AbstractThe synthesis and characterisation of a novel isomeric family of closo‐carborane‐containing PtII complexes ((R/S)‐(1–4)⋅2 NO3) are reported. Related complexes (5⋅NO3 and 6⋅NO3) that contain the 7,8‐nido‐carborane cluster were obtained from the selective deboronation of the 1,2‐closo‐carborane analogues. The corresponding water‐soluble supramolecular 1:1 host–guest β‐cyclodextrin (β‐CD) adducts ((R/S)‐(1–4)⋅β‐CD⋅2 NO3) were also prepared and fully characterised. HR‐ESI‐MS experiments confirmed the presence of the host–guest adducts, and 2D‐1H{11B} ROESY NMR studies showed that the boron clusters enter the β‐CD from the side of the wider annulus. Isothermal titration calorimetry (ITC) experiments revealed enthalpically driven 1:1 and higher‐order supramolecular interactions between β‐CD and (R/S)‐(1–4)⋅2 NO3 in aqueous solution. A comparison of the predominate 1:1 binding mode established that the affinity of β‐CD for the guest molecule is mainly influenced by the pyridyl ring substitution pattern and chirality of the host, whilst the nature of the closo‐carborane isomer also plays some role, with the most favourable structural features for β‐CD binding being the presence of the 4‐pyridyl ring, 1,12‐closo‐carborane, and an S configuration. The results reported here represent the first comprehensive calorimetric study of the supramolecular interactions between closo‐carborane compounds and β‐CD, and it provides fascinating insights into the structural features influencing the thermodynamics of this phenomenon.
Electronic Coupling between Two Amine Redox Sites through the 5,5′‐Positions of Metal‐Chelating 2,2′‐Bipyridines
Authors: Nie Hai‐Jing , Chen Xialing , Yao Chang‐Jiang , Zhong Yu‐Wu , Hutchison Geoffrey R. , Yao Jiannian 
Published: September 2012

AbstractElectron delocalization of new mixed‐valent (MV) systems with the aid of lateral metal chelation is reported. 2,2′‐Bipyridine (bpy) derivatives with one or two appended di‐p‐anisylamino groups on the 5,5′‐positions and a coordinated [Ru(bpy)2] (bpy=2,2′‐bipyridine), [Re(CO)3Cl], or [Ir(ppy)2] (ppy=2‐phenylpyridine) component were prepared. The single‐crystal molecular structure of the bis‐amine ligand without metal chelation is presented. The electronic properties of these complexes were studied and compared by electrochemical and spectroscopic techniques and DFT/TDDFT calculations. Compounds with two di‐p‐anisylamino groups were oxidized by a chemical or electrochemical method and monitored by near‐infrared (NIR) absorption spectral changes. Marcus–Hush analysis of the resulting intervalence charge‐transfer transitions indicated that electron coupling of these mixed‐valent systems is enhanced by metal chelation and that the iridium complex has the largest coupling. TDDFT calculations were employed to interpret the NIR transitions of these MV systems.
Ruthenium(II/III)‐Based Compounds with Encouraging Antiproliferative Activity against Non‐small‐Cell Lung Cancer
Authors: Nagy Eszter M. , Pettenuzzo Andrea , Boscutti Giulia , Marchiò Luciano , Dalla Via Lisa , Fregona Dolores 
Published: September 2012

AbstractHereby we present the synthesis of several ruthenium(II) and ruthenium(III) dithiocarbamato complexes. Proceeding from the Na[trans‐RuIII(dmso)2Cl4] (2) andcis‐[RuII(dmso)4Cl2] (3) precursors, the diamagnetic, mixed‐ligand [RuIIL2(dmso)2] complexes4and5, the paramagnetic, neutral [RuIIIL3] monomers6and7, the antiferromagnetically coupled ionic α‐[RuIII2L5]Cl complexes8and9as well as the β‐[RuIII2L5]Cl dinuclear species10and11(L=dimethyl‐ (DMDT) and pyrrolidinedithiocarbamate (PDT)) were obtained. All the compounds were fully characterised by elemental analysis as well as1H NMR and FTIR spectroscopy. Moreover, for the first time the crystal structures of the dinuclear β‐[RuIII2(dmdt)5]BF4⋅CHCl3⋅CH3CN and of the novel [RuIIL2(dmso)2] complexes were also determined and discussed. For both the mono‐ and dinuclear RuIIand RuIIIcomplexes the central metal atoms assume a distorted octahedral geometry. Furthermore, in vitro cytotoxicity of the complexes has been evaluated on non‐small‐cell lung cancer (NSCLC) NCI‐H1975 cells. All the mono‐ and dinuclear RuIIIdithiocarbamato compounds (i.e., complexes6–10) show interesting cytotoxic activity, up to one order of magnitude higher with respect to cisplatin. Otherwise, no significant antiproliferative effect for either the precursors2and3or the RuIIcomplexes4and5has been observed.
Highly Enantioselective Synthesis of 1,2,3‐Substituted Cyclopropanes by Using α‐Iodo‐ and α‐Chloromethylzinc Carbenoids
Authors: Beaulieu Louis‐Philippe B. , Zimmer Lucie E. , Gagnon Alexandre , Charette André B. 
Published: September 2012

AbstractHerein, we report the enantio‐ and diastereoselective formation of trans‐iodo‐ and trans‐chlorocyclopropanes from α‐iodo‐ and α‐chlorozinc carbenoids by using a dioxaborolane‐derived chiral ligand. The synthetically useful iodocyclopropane building blocks were derivatized by an electrophilic trapping of the corresponding cyclopropyl lithium species or a Negishi coupling to give access to a variety of enantioenriched 1,2,3‐substituted cyclopropanes. The synthetic utility of this method was demonstrated by the formal synthesis of an HIV‐1 protease inhibitor. In addition, the related stereoselective bromocyclopropanation was also investigated. New insights about the relative electrophilicity of haloiodomethylzinc carbenoids are also presented.
Catalyst‐Free Imidation of Allyl Sulfides with Chloramine‐T and Subsequent [2,3]‐Sigmatropic Rearrangement
Authors: Jiang Yubo , Mo Fanyang , Qiu Di , Kuang Chunxiang , Zhang Yan , Wang Jianbo 
Published: September 2012

AbstractA facile synthesis of various allyl sulfonamides based on imidation of allyl sulfides with chloramine‐T and subsequent [2,3]‐sigmatropic rearrangement has been achieved without metal catalysts. The reaction completes smoothly within 10 min, providing excellent yields in environment friendly solvent of alcohol. Functional groups such as bromine, hydroxyl, protected amido and aldehyde are tolerant under this condition.