bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical safety, pharmacokinetics, and efficacy of ambrisentan therapy in children with pulmonary arterial hypertension
Authors: Takatsuki Shinichi , Rosenzweig Erika B. , Zuckerman Warren , Brady Daniela , Calderbank Michelle , Ivy D. Dunbar 
Published: April 2012

AbstractRecent trials in adult PAH revealed the efficacy of ambrisentan. However, in children with PAH, the clinical safety and pharmacokinetics of ambrisentan has not been well studied. Our aim was to investigate the clinical safety, pharmacokinetics, tolerability, and efficacy of endothelin receptor antagonist therapy with ambrisentan in children with pulmonary arterial hypertension (PAH). This retrospective cohort study provides clinical data from pediatric patients with PAH receiving ambrisentan as add‐on therapy or transition from bosentan. Safety included evaluation of adverse events including aminotransferase abnormalities. The clinical impact was evaluated by improvement from baseline in clinical variables. A total of 38 pediatric patients with PAH received ambrisentan. Fifteen of 38 patients were switched from bosentan to ambrisentan. The remaining 23 children were treated with ambrisentan as an add‐on therapy due to disease progression. In both transition and add‐on cases, mean pulmonary artery pressure significantly improved (transition; 55 ± 18 vs. 45 ± 20 mmHg, n = 13, P = 0.04, add‐on; 52 ± 17 vs. 45 ± 19 mmHg, n = 13, P = 0.03) during the follow‐up. World Health Organization functional class improved in 31% of patients, but one patient required an atrial septostomy due to disease progression during the follow‐up period (median, range; 20, 4–44 months). Five patients (13%) discontinued ambrisentan due to severe headache, lack of clinical efficacy, or near syncope. Ten patients (26%) had side effects associated with ambrisentan treatment, including nasal congestion, headache, and flushing. However, no patients had aminotransferase abnormalities and there were no deaths after initiation of ambrisentan during follow‐up. Pharmacokinetics were evaluated in sixteen children treated with ambrisentan from 2.5 mg to 10.0 mg; the mean peak plasma concentration was 738 ± 452 ng/ml, mean time to peak plasma concentration was 3.2 ± 2.1 hours, and mean area under the curve plasma concentration was 6657 ± 4246 ng·hour/ml. In conclusion, initial experience with ambrisentan in children suggests that treatment is safe with similar pharmacokinetics to those in adults and may improve PAH in some children. Pediatr Pulmonol. 2013; 48:27–34. © 2012 Wiley Periodicals, Inc.
Mechanism of strain retention and shape memory in main chain liquid crystalline networks
Authors: Ren Wanting , Griffin Anselm C. 
Published: April 2012

AbstractLiquid crystalline networks (LCNs) are described in which there is anelasticity in strain recovery response (under zero load) after uniaxial tensile loading. This strain retention is shown as a function of time after release of load and is further characterized by thermal, X‐ray, and stress/strain experiments. It was found that, at temperatures in the smectic phase far below the isotropization temperature, this LCN film retains significant levels of strain when in the monodomain state. On free recovery (zero load) of the LCN film there is a rapid elastic response followed by a slow anelastic response for those films that had undergone a polydomain‐to‐monodomain transition during the initial imposed strain regimen. It is postulated that the mechanism leading to the strain retention involves nanosegregation‐driven pinning of unfolded hairpins in shallow energy wells and that this effect is responsible for the thermally activated recovery of strain (shape memory) at elevated temperatures.magnified imageStress–strain curves of pre‐strained C11(MeHQ)Si8XL10 LC networks having various initial strains: (a) 350%, (b) 300%, (c) 250%, (d) 200%, (e) 150%, (f) 100%, and (g) 50%.
Modeling absorption of the kindling fluorescent protein with the neutral form of the chromophore
Authors: Topol Igor , Collins Jack , Mironov Vladimir , Savitsky Alexander , Nemukhin Alexander 
Published: April 2012

AbstractKindling fluorescent protein (KFP) is an important member of the colored proteins family widely used as biomarkers in living cells. We apply quantum chemistry modeling of KFP properties by computing structure and spectra of a large molecular cluster mimicking the chromophore‐containing pocket, assuming the protonated (neutral) form of the chromophore in the trans configuration. We provide evidence that this protein conformation accounts for the previously observed but unassigned absorption band at 445 nm. We demonstrate that the structure and charge of the amino acid residues nearest to the chromophore play a role in the shifts in the absorption wave length, thus underlying a strong role of intermolecular interactions when considering properties of the fluorescent proteins. © 2012 Wiley Periodicals, Inc.
The optimization of wireless power transmission: design and realization
Authors: Jia Zhiwei , Yan Guozheng , Liu Hua , Wang Zhiwu , Jiang Pingping , Shi Yu 
Published: April 2012

AbstractBackgroundA wireless power transmission system is regarded as a practical way of solving power‐shortage problems in multifunctional active capsule endoscopes.MethodsThe uniformity of magnetic flux density, frequency stability and orientation stability are used to evaluate power transmission stability, taking into consideration size and safety constraints. Magnetic field safety and temperature rise are also considered. Test benches are designed to measure the relevent parameters. Finally, a mathematical programming model in which these constraints are considered is proposed to improve transmission efficiency. To verify the feasibility of the proposed method, various systems for a wireless active capsule endoscope are designed and evaluated.ResultsThe optimal power transmission system has the capability to supply continuously at least 500 mW of power with a transmission efficiency of 4.08%.ConclusionsThe example validates the feasibility of the proposed method. Introduction of novel designs enables further improvement of this method. Copyright © 2012 John Wiley & Sons, Ltd.
Input‐to‐state stability of a class of Lur'e descriptor systems
Authors: Yang Chunyu , Zhang Qingling , Huang Shoudong 
Published: April 2012

SUMMARYThis paper considers a class of Lur'e descriptor systems (LDS) subject to exogenous disturbances. The concept of input‐to‐state stability (ISS) is generalized to descriptor systems. Such a notion characterizes the robust stability of the full state of the systems. Based on the conventional ISS theory, a sufficient condition expressed by linear matrix inequalities (LMIs) for the LDS to be ISS is derived. It is further shown that this condition also guarantees a special class of LDS to be of index one. Then, a state feedback controller is designed to make the closed‐loop system ISS. Finally, an example is given to illustrate the obtained results. Copyright © 2012 John Wiley & Sons, Ltd.
Exponential stability and stabilization for nonlinear descriptor systems with discrete and distributed delays
Authors: Wu Jiancheng , Lu Guoping , Wo Songlin , Xiao Xiaoqing 
Published: April 2012

SUMMARYThis paper discusses the exponential stability and stabilization for nonlinear descriptor systems with discrete and distributed delays. In terms of the Lyapunov method, the exponential stability of the slow subsystem is firstly obtained. Then, a new homotopy‐based approach is proposed to investigate the exponential stability of the fast subsystem. By an estimate of the weighted matrix norm for a nonlinear mapping, the exponential stability of the fast subsystem and thus delay‐dependent sufficient conditions for the exponential stability of the systems are obtained. In addition, a state feedback controller is designed for the stabilization of the nonlinear descriptor systems. Finally, the effectiveness of the proposed approach is illustrated by numerical examples. Copyright © 2012 John Wiley & Sons, Ltd.
Modeling and security analysis of enterprise network using attack–defense stochastic game Petri nets
Authors: Wang Yuanzhuo , Li Jingyuan , Meng Kun , Lin Chuang , Cheng Xueqi 
Published: April 2012

ABSTRACTIn this paper, we propose a novel modeling method attack–defense stochastic game Petri nets (or ADSGN) to model and analyze the security issues in enterprise network. We firstly give the definition and modeling method algorithm of ADSGN and then propose the algorithm of the strategy. The proposed ADSGN method is successfully applied to describe the attack and defense courses in the enterprise network. Finally, we analyze the mean time to first security breach and the mean time to security breach in the enterprise network quantifiably, and proved that our method can also be applied to other areas with respect to game issues. Copyright © 2012 John Wiley & Sons, Ltd.
Who bribes? Evidence from the United Nations' oil‐for‐food program
Authors: Jeong Yujin , Weiner Robert J. 
Published: April 2012

AbstractHow do managers react in an environment where bribery is likely to bring high rewards, but also presents high risks? We examine the supply side (firms' illicit payments) of bribery in a global setting, using the United Nations' (UN) Oil‐for‐Food Program, part of UN sanctions on Iraq. Some companies helped Iraq circumvent UN sanctions through bribe payments in the form of illicit surcharges. Our transaction‐level analysis of factors affecting bribe payments draws on the economic theory of crime, agency theory, and home country institutions. Results suggest that firms pay larger bribes when there are stronger financial and managerial incentives, but pay less when their home countries have implemented the OECD Anti‐Bribery Convention. We find little relationship between a widely used country‐level corruption perception index and firms' actual bribery. Copyright © 2012 John Wiley & Sons, Ltd.
Asymmetric Hybrid Silica Nanomotors for Capture and Cargo Transport: Towards a Novel Motion‐Based DNA Sensor
Authors: Simmchen Juliane , Baeza Alejandro , Ruiz Daniel , Esplandiu Maria José , Vallet‐Regí Maria 
Published: April 2012

AbstractAn innovative self‐propelled nanodevice able to perform motion, cargo transport, and target recognition is presented. The system is based on a mesoporous motor particle, which is asymmetrically functionalized by the attachment of single‐stranded DNA onto one of its faces, while catalase is immobilized on the other face. This enzyme allows catalytic decomposition of hydrogen peroxide to oxygen and water, giving rise to the driving force for the motion of the whole system. Moreover the motor particles are able to capture and transport cargo particles functionalized with a noncomplementary single‐stranded DNA molecule, only if a specific oligonucleotide sequence is present in the media. Functionalization with characteristic oligonucleotide sequences in the system implies a potential for further developments for lab‐on‐chip devices with applications in biomedical applications.
Resonant Laser‐Induced Formation of Double‐Walled Carbon Nanotubes from Peapods under Ambient Conditions
Authors: Berd Mourad , Puech Pascal , Righi Ariete , Benfdila Arezki , Monthioux Marc 
Published: April 2012

AbstractThe selective excitation of fullerenes encapsulated in single‐walled carbon nanotubes (SWCNTs) is carried out by irradiating them using a UV laser, the wavelength of which corresponds exactly to their maximum of absorption. Under such conditions, fullerenes strongly absorb the laser energy, open, and break, while the containing SWCNT merely acts as both a nanoreactor and a mold which is only weakly heated by the laser. The containing tube confines the fullerene fragments, promotes their reconstruction into an inner tube, and protects them from air oxidation. This leads to the overall formation of double‐walled carbon nanotubes (DWCNTs). The transformation is found to strongly depend on the laser irradiance and dose. This proves that the related mechanism is a multiphoton photolysis, different from the previous heat‐induced transformation attempts found in the literature, whether the heat is produced by means of a thermostat, infrared laser, or nonresonant UV laser. The actual peapod‐to‐DWCNT transformation is monitored by Raman spectroscopy and high‐resolution transmission electron microscopy.
Adjuvant Properties of Mesoporous Silica Particles Tune the Development of Effector T Cells
Authors: Vallhov Helen , Kupferschmidt Natalia , Gabrielsson Susanne , Paulie Staffan , Strømme Maria , Garcia‐Bennett Alfonso E. , Scheynius Annika 
Published: April 2012

AbstractAlum is the most frequently used adjuvant today, primarily inducing Th2 responses. However, Th1‐type responses are often desirable within immune therapy, and therefore the development of new adjuvants is greatly needed. Mesoporous silica particles with a highly ordered pore structure have properties that make them very interesting for future controlled drug delivery systems, such as controllable particle and pore size; they also have the ability to induce minor immune modulatory effects, as previously demonstrated on human‐monocyte‐derived dendritic cells (MDDCs). In this study, mesoporous silica particles are shown to be efficiently engulfed by MDDCs within 2 h, probably by phagocytic uptake, as seen by confocal microscopy and transmission electron microscopy. A co‐culture protocol is developed to evaluate the capability of MDDCs to stimulate the development of naïve CD4+ T cells in different directions. The method, involving ELISpot as a readout system, demonstrates that MDDCs, after exposure to mesoporous silica particles (AMS‐6 and SBA‐15), are capable of tuning autologous naïve T cells into different effector cells. Depending on the size and functionalization of the particles added to the cells, different cytokine patterns are detected. This suggests that mesoporous silica particles can be used as delivery vehicles with tunable adjuvant properties, which may be of importance for several medical applications, such as immune therapy and vaccination.
Improved Photodynamic Cancer Treatment by Folate‐Conjugated Polymeric Micelles in a KB Xenografted Animal Model
Authors: Syu Wei‐Jhe , Yu Hsiu‐Ping , Hsu Chia‐Yen , Rajan Yeasudhasan Christu , Hsu Yuan‐Hung , Chang Yuan‐Chia , Hsieh Wen‐Yuan , Wang Chau‐Hui , Lai Ping‐Shan 
Published: April 2012

AbstractPhotodynamic therapy (PDT) is a light‐induced chemical reaction that produces localized tissue damage for the treatment of cancers and various nonmalignant conditions. In the clinic, patients treated with PDT should be kept away from direct sunlight or strong indoor lighting to avoid skin phototoxicity. In a previous study, it was demonstrated that the skin phototoxicity of meta‐tetra(hydroxyphenyl)chlorin (m‐THPC), a photosensitizer used in the clinic, can be significantly reduced after micellar encapsulation; however, no improvement in antitumor efficacy was observed. In this work, a folate‐conjugated polymeric m‐THPC delivery system is developed for improving tumor targeting of the photosensitizer, preventing photodamage to the healthy tissue, and increasing the effectiveness of the photosensitizers. The results demonstrate that folate‐conjugated m‐THPC‐loaded micelles with particle sizes around 100 nm are taken up and accumulated by folate receptor‐overexpressed KB cells in vitro and in vivo, and their PDT has no significant adverse effects on the body weight of mice. After an extended delivery time, a single dose of folate‐conjugated m‐THPC‐loaded micelles has higher antitumor effects (tumor growth inhibition = 92%) through inhibition of cell proliferation and reduction of vessel density than free m‐THPC or m‐THPC‐loaded micelles at an equivalent m‐THPC concentration of 0.3 mg kg−1 after irradiation. Furthermore, folate‐conjugated m‐THPC‐loaded micelles at only 0.2 mg kg−1 m‐THPC have a similar antitumor efficacy to m‐THPC or m‐THPC‐loaded micelles with the m‐THPC concentration at 0.3 mg kg−1, which indicates that the folate conjugation on the micellar photosensitizer apparently reduces the requirement of m‐THPC for PDT. Thus, folate‐conjugated m‐THPC‐loaded micelles with improved selectivity via folate–folate receptor interactions have the potential to reduce, not only the skin photosensitivity, but also the drug dose requirement for clinical PDT.
A Redox‐Switchable Au8‐Cluster Sensor
Authors: Wu Te‐Haw , Hsu Yu‐Yen , Lin Shu‐Yi 
Published: April 2012

AbstractThe proof of concept of a simple sensing platform based on the fluorescence of a gold cluster consisting of eight atoms, which is easily manipulated by reduction and oxidation of a specific molecule in the absence of chemical linkers, is demonstrated. Without using any coupling reagents to arrange the distance of the donor–acceptor pair, the fluorescence of the Au8‐cluster is immediately switched off in the presence of 2‐pyridinethiol (2‐PyT) quencher. Through an upward‐curving Stern–Volmer plot, the system shows complex fluorescence quenching with a combination of static and dynamic quenching processes. To analyze the static quenching constant (V) by a “sphere of action” model, the collisional encounter between the Au8‐cluster and 2‐PyT presents a quenching radius (r) ≈5.8 nm, which is larger than the sum of the radii of the Au8‐cluster and 2‐PyT. This implies that fluorescence quenching can occur even though the Au8‐cluster and 2‐PyT are not very close to each other. The quenching pathway may be derived from a photoinduced electron‐transfer process of the encounter pair between the Au8‐cluster (as an electron donor) and 2‐PyT (as an electron acceptor) to allow efficient fluorescence quenching in the absence of coupling reagents. Interestingly, the fluorescence is restored by oxidation of 2‐PyT to form the corresponding disulfide compound and then quenched again after the reduction of the disulfide. This redox‐switchable fluorescent Au8‐cluster platform is a novel discovery, and its utility as a promising sensor for detecting H2O2‐generating enzymatic transformations is demonstrated.
Structural Effect and Mechanism of C70‐Carboxyfullerenes as Efficient Sensitizers against Cancer Cells
Authors: Liu Qiaoling , Guan Mirong , Xu Li , Shu Chunying , Jin Chan , Zheng Junpeng , Fang Xiaohong , Yang Yongji , Wang Chunru 
Published: April 2012

AbstractCarboxyfullerenes with different adduct numbers and cage sizes are tested as photosensitizers for photodynamic therapy (PDT). The photodynamic efficiency of these carboxyfullerenes depends mainly on the cage size, C60 versus C70, and to a lesser extent on the adduct numbers. In particular, malonic acid modified C70 fullerenes are more efficient than their C60 counterparts as photosensitizers, and the mechanism of cell death induced by C70‐carboxyfullerene under light irradiation is investigated in detail. The results indicate that cell death occurs via necrosis accompanied by membrane blebbing, which is a unique phenomenon for photosensitizer‐induced cell death. Since C70‐carboxyfullerene displays an efficient PDT property and negligible dark cytotoxicity, it is promising for use in PDT applications, especially in vascular capillary diseases usually occurring under the surface.
Chiral Pinwheel Clusters Lacking Local Point Chirality
Authors: Sun Kai , Shao Ting‐Na , Xie Jia‐Le , Lan Meng , Yuan Hong‐Kuan , Xiong Zu‐Hong , Wang Jun‐Zhong , Liu Ying , Xue Qi‐Kun 
Published: April 2012

AbstractThe supramolecular pinwheel cluster is a unique chiral structure with evident handedness. Previous studies reveal that the chiral pinwheels are composed of chiral or achiral molecules with polar groups, which result in strong intermolecular interactions such as hydrogen‐bonding or dipole interactions. Herein, it is shown that the simple linear aromatic molecule, pentacene, can be self‐assembled into large chiral pinwheel clusters on the semimetal Bi(111) surface, due to enhanced intermolecular interactions. The pentacene pinwheels reveal two levels of organizational chirality: the chiral hexamers resulting from asymmetric shifting along the long molecular axis, and chiral arrangement of six hexamers with a rotor motif. Furthermore, a new relation between the local point chirality and organizational chirality is identified from the pinwheels: the former is not essential for the latter in 2D pinwheel clusters of the pentacene molecule.
Playing MUSIC — building context‐aware and self‐adaptive mobile applications
Authors: Floch J. , Frà C. , Fricke R. , Geihs K. , Wagner M. , Lorenzo J. , Soladana E. , Mehlhase S. , Paspallis N. , Rahnama H. , Ruiz P.A. , Scholz U. 
Published: April 2012

SUMMARYAlthough the idea of context‐awareness was introduced almost two decades ago, few mobile software applications are available today that can sense and adapt to their run‐time environment. The development of context‐aware and self‐adaptive applications is complex and few developers have experience in this area. On the basis of several demonstrators built by the joint European research project MUSIC, this paper describes typical context and adaptation features relevant for the development of context‐aware and self‐adaptive mobile applications. We explain how the demonstrators were realised using the open‐source platform MUSIC and present the feedback of the developers of these demonstrators. The main contribution of this paper is to show how the development complexity of context‐aware and self‐adaptive mobile applications can be mastered by using an adaptation framework such as MUSIC. Copyright © 2012 John Wiley & Sons, Ltd.
MicroRNAs Regulate p21Waf1/Cip1 Protein Expression and the DNA Damage Response in Human Embryonic Stem Cells
Authors: Dolezalova Dasa , Mraz Marek , Barta Tomas , Plevova Karla , Vinarsky Vladimir , Holubcova Zuzana , Jaros Josef , Dvorak Petr , Pospisilova Sarka , Hampl Ales 
Published: April 2012

Abstract
Studies of human embryonic stem cells (hESCs) commonly describe the nonfunctional p53-p21 axis of the G1/S checkpoint pathway with subsequent relevance for cell cycle regulation and the DNA damage response (DDR). Importantly, p21 mRNA is clearly present and upregulated after the DDR in hESCs, but p21 protein is not detectable. In this article, we provide evidence that expression of p21 protein is directly regulated by the microRNA (miRNA) pathway under standard culture conditions and after DNA damage. The DDR in hESCs leads to upregulation of tens of miRNAs, including hESC-specific miRNAs such as those of the miR-302 family, miR-371-372 family, or C19MC miRNA cluster. Most importantly, we show that the hESC-enriched miRNA family miR-302 (miR-302a, miR-302b, miR-302c, and miR-302d) directly contributes to regulation of p21 expression in hESCs and, thus, demonstrate a novel function for miR-302s in hESCS. The described mechanism elucidates the role of miRNAs in regulation of important molecular pathway governing the G1/S transition checkpoint before as well as after DNA damage.