bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperbranched poly (amine‐ester)‐poly (lactide‐co‐glycolide) copolymer and their nanoparticles as paclitaxel delivery system
Authors: Wu Yan , Wang Tie wei , Li Mingjun , Gao Hongxia 
Published: December 2010

AbstractA new hyperbranched poly (amine‐ester)‐poly (lactide‐co‐glycolide) copolymer (HPAE‐co‐PLGA) was synthesized by ring‐opening polymerization of D, L‐lactide (DLLA) glycolid and branched poly (amine‐ester) (HPAE‐OHs) with Sn(Oct)2 as catalyst. The chemical structures of copolymers were determined by FT‐IR, 1H‐NMR(13C NMR), TGA and their molecular weights were determined by gel permeation chromatography (GPC). Paclitaxel‐loaded copolymer nanoparticles were prepared by the nanoprecipitation method. Their physicochemical characteristics, e.g. morphology and nanoparticles size distribution were then evaluated by means of fluorescence spectroscopy, environmental scanning electron microscopy (ESEM), and dynamic light scattering (DLS).Paclitaxel‐loaded nanoparticles assumed a spherical shape and have unimodal size distribution. It was found that the chemical composition of the nanoparticles was a key factor in controlling nanoparticles size, drug‐loading content, and drug release behavior. As the molar ratio of DL‐lactide/glycolide to HPAE increased, the nanoparticles size and drug‐loading content increased, and the drug release rate decreased. The antitumor activity of the paclitaxel‐loaded HPAE‐co‐PLGA nanoparticles against human liver cancer H7402 cells was evaluated by 3‐(4, 5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide (MTT) method. The paclitaxel‐loaded HPAE‐co‐PLGA nanoparticles showed comparable anticancer efficacy with the free drug. Copyright © 2010 John Wiley & Sons, Ltd.
Incidence and pattern of radiological central nervous system Langerhans cell histiocytosis in children: A population based study
Authors: Laurencikas Evaldas , Gavhed Désirée , Stålemark Helen , Hooft Ingrid van't , Prayer Daniela , Grois Nicole , Henter Jan‐Inge 
Published: December 2010

AbstractBackgroundPatients with Langerhans cell histiocytosis (LCH) may develop neurodegeneration and other central nervous system (CNS) dysfunctions revealed by brain magnetic resonance imaging (MRI). We estimated the incidence and pattern of pathological brain MRI findings in a well‐defined, population‐based cohort of children with LCH.MethodsAmong children under 15 years of age diagnosed with LCH in the Stockholm County during 1992–2001, brain MRI was performed at a single center in children with clinical and/or laboratory signs of CNS involvement, including endocrine dysfunction.ResultsOut of the 29 children (16 males, 13 females) diagnosed with LCH, brain MRI was performed based on clinical indications in 16 children (55%) with either abnormal endocrine findings (n = 6), such as diabetes insipidus (n = 5), low IGF‐1 (n = 1), or panhypopituitarism (n = 1), or clinical CNS symptoms (n = 10). CNS MRI abnormalities were demonstrated in eight children (28%), at a median time of 3.5 years after LCH diagnosis (range 1–11.4 years). Altogether 7 of the 29 children (24%) had MRI findings associated with neurodegeneration, corresponding to a minimal incidence of 2.1/106 children per year. Neurodegenerative abnormalities tended to be more frequent in patients with craniofacial involvement (P = 0.12).ConclusionsThe minimal annual incidence rate of neurodegenerative associated radiographic findings in LCH is estimated at 2.1/106 children (24% of all children with LCH). An important question is whether all patients with LCH, or certain forms of LCH, should be recommended for a late follow‐up examination including MRI. In patients with CNS‐LCH, neurological, neuropsychological, neurophysiological, neurochemical and neuroradiological follow‐up assessment is suggested. Pediatr Blood Cancer 2011;56:250–257. © 2010 Wiley‐Liss, Inc.
The differences between retained and promoted children in educational services received
Authors: Peterson Lisa S. , Hughes Jan N. 
Published: December 2010

AbstractThe purpose of this study was to determine whether students retained in first grade, relative to similarly low‐achieving students who were promoted, differed in the number of remedial educational services received by students in the pre‐retention year and in the repeat year. Study participants were 769 relatively low‐achieving first‐grade students, of whom 165 were retained in first grade and 604 were promoted. Controlling for students' conditional probability of being retained, based on propensity scores calculated prior to retention, retained students received the same number of services as did promoted students during the pre‐retention year. The following year, when retained students were in first grade and promoted students were in second grade, retained students received fewer services than promoted students. Furthermore, retained children had a larger decrease in services from Year 1 to Year 2. These data support the notion that grade retention is being used as the primary intervention instead of a component of a more comprehensive remediation plan. © 2010 Wiley Periodicals, Inc.
The impact of teacher credentials on ADHD Stigma Perceptions
Authors: Bell Lindsay , Long Susanne , Garvan Cynthia , Bussing Regina 
Published: December 2010

AbstractAttention‐Deficit/Hyperactivity Disorder (ADHD) is one of the most frequently diagnosed psychiatric disorders in childhood and adolescence. It is associated with high levels of stigma, which may lead to treatment barriers, self‐fulfilling prophecies, and social rejection. This study established the reliability of the ADHD Stigma Questionnaire (ASQ) when applied to teachers by evaluating its internal consistency and confirmed the previously reported factor structure. In addition, the study examined the extent to which holding a special education certification and having years of teaching experience impact teachers' perceptions of ADHD stigma. Results indicated that teachers holding special education certification endorsed higher ratings, which indicated high stigma perceptions, on the Overall Stigma score, as well as the three subscales, Disclosure Concerns, Negative Self‐Image, and Concern with Public Attitudes; however, years of teaching experience was not related to stigma scores. Implications for teacher training practices are discussed. © 2010 Wiley Periodicals, Inc.
Merocyanines based on 1,3‐indanedione: electronic structure and solvatochromism
Authors: Kulinich Andrii V. , Derevyanko Nadia A. , Mikitenko Elena K. , Ishchenko Alexander A. 
Published: December 2010

AbstractA series of merocyanines derived from 1,3‐indanedione and heterocycles of various electron‐donating properties was studied in detail. Their solvatochromic properties were explored in a wide range of solvent polarities to reveal the dependences of their chromacity and electronic structure on the key structural parameters – the properties of a donor heterocycle and the polymethine chain length. Also the dyes were studied by NMR spectroscopy and by quantum chemical calculations, both with the semiempirical AM1 and the non‐empirical density functional theory/B3LYP method. The solvatochromic properties of the explored dyes are rather close to those of merocyanines derived from malononitrile as acceptor group. Appreciable distinctions were observed only in protic ethanol; obviously, they are connected with the formation of solvent–solute H‐bonds in the case of 1,3‐indanedione derivatives. The electron‐acceptor properties of 1,3‐indanedione were found to be somewhat stronger in comparison with those of malononitrile even in aprotic solvents, contrary to the known literature data. Analysis of the merocyanines' molecular orbitals and simulation of their electronic spectra were carried out both in vacuum and in the solvent matrix, and the absorption electronic transitions were analyzed. Static nonlinear optical properties were calculated for both the new merocyanines and the corresponding cationic and anionic cyanine dyes. Copyright © 2010 John Wiley & Sons, Ltd.
Radical anions containing the dioxidated 1,2,5‐thiadiazole heterocycle. Part II
Authors: Mirífico María Virginia , Caram José Alberto , Gennaro Ana María , Cobos Carlos J. , Vasini Enrique Julio 
Published: December 2010

AbstractRadical anions from several 3,4‐aryl‐disubstituted derivatives of 1,2,5‐thiadiazole 1,1‐dioxide were accumulated through chemical reduction of the substrates in aprotic solvents. The radical anions were characterized by electron spin resonance and cyclic voltammetry. DFT theoretical calculations were also performed for the 3,4‐diphenyl derivative. The course of the reductions was followed using cyclic voltammetry. Uncommon reductants, such as amides, were found to be effective under certain conditions. Copyright © 2010 John Wiley & Sons, Ltd.
Identification of CCR2‐binding features in Cytl1 by a CCL2‐like chemokine model
Authors: Tomczak Aurelie , Pisabarro M. Teresa 
Published: December 2010

AbstractChemokines are small secreted proteins that play an important role in immune responses and have also been shown to be involved in cartilage development and contributing to pathogenesis of a variety of diseases. They present a conserved 3D structure, so‐called IL8‐like chemokine fold, which is supported by conserved cysteines forming intra‐molecular disulfide bonds. These cysteine sequence motifs have often been used to find new chemokine family members by sequence‐based database searches. However, it has been shown that different patterns can provide disulfide bonds fitting into an IL8‐like architecture, which has been the key to identify new remote homologues of the IL8‐like chemokine family. We report a structural–functional characterization of cytokine‐like protein 1 (Cytl1) by a combination of different computational structure‐based techniques. Previous studies based on sequence analysis and secondary structure predictions reported that Cytl1 might adopt a 4‐helical cytokine fold. However, our detailed molecular modeling studies and structure‐based functional analysis strongly suggest that Cytl1 is more likely to adopt an IL8‐like chemokine fold, in particular similar to CCL2 (monocyte chemoattractant protein 1, MCP‐1). Moreover, we identify in a CCL2‐like 3D model of Cytl1 the necessary reported features to signal through the chemokine receptor CCR2. Those discovered structural features of Cytl1 as CCL2‐like chemokine, together with the fact that both, CCL2 and Cytl1, are known to be involved in cartilage development and pathogenesis of osteoarthritis and rheumatoid arthritis, make us hypothesize that Cytl1 could be a structurally and functionally related analog of CCL2 signaling through the chemokine receptor CCR2. Proteins 2011. © 2011 Wiley‐Liss, Inc.
Structural plasticity of staphylococcal nuclease probed by perturbation with pressure and pH
Authors: Kitahara Ryo , Hata Kazumi , Maeno Akihiro , Akasaka Kazuyuki , Chimenti Michael S. , Garcia‐Moreno E. Bertrand , Schroer Martin A. , Jeworrek Christoph , Tolan Metin , Winter Roland , Roche Julien , Roumestand Christian , Montet de Guillen Karine , Royer Catherine A. 
Published: December 2010

AbstractThe ionization of internal groups in proteins can trigger conformational change. Despite this being the structural basis of most biological energy transduction, these processes are poorly understood. Small angle X‐ray scattering (SAXS) and nuclear magnetic resonance (NMR) spectroscopy experiments at ambient and high hydrostatic pressure were used to examine how the presence and ionization of Lys‐66, buried in the hydrophobic core of a stabilized variant of staphylococcal nuclease, affect conformation and dynamics. NMR spectroscopy at atmospheric pressure showed previously that the neutral Lys‐66 affects slow conformational fluctuations globally, whereas the effects of the charged form are localized to the region immediately surrounding position 66. Ab initio models from SAXS data suggest that when Lys‐66 is charged the protein expands, which is consistent with results from NMR spectroscopy. The application of moderate pressure (<2 kbar) at pH values where Lys‐66 is normally neutral at ambient pressure left most of the structure unperturbed but produced significant nonlinear changes in chemical shifts in the helix where Lys‐66 is located. Above 2 kbar pressure at these pH values the protein with Lys‐66 unfolded cooperatively adopting a relatively compact, albeit random structure according to Kratky analysis of the SAXS data. In contrast, at low pH and high pressure the unfolded state of the variant with Lys‐66 is more expanded than that of the reference protein. The combined global and local view of the structural reorganization triggered by ionization of the internal Lys‐66 reveals more detectable changes than were previously suggested by NMR spectroscopy at ambient pressure. Proteins 2011. © 2011 Wiley‐Liss, Inc.
Radiolytic degradation mechanism of gallic acid and its end‐products
Authors: Melo R. P. , Leal J. P. , Botelho M. L. 
Published: December 2010

AbstractGallic acid is one of the most representative biorecalcitrant phenolic compounds present in cork processing wastewater. In this communication, chemical oxidation of gallic acid was studied by gamma irradiation as an advanced oxidation process. This technology turns out to be an advantageous tool for the degradation of gallic acid. The results obtained by UV‐Vis and electrospray ionization mass spectrometry (ESI‐MS) techniques are in agreement concerning the suitability of this technique to degrade gallic acid. ESI‐MS and ESI‐MS2 monitoring of the non‐irradiated and irradiated gallic acid solutions leads to the identification of the main intermediate products. Based on the overall results obtained a consistent mechanism of radiolytic degradation of gallic acid is proposed. The application of radiation as a tool to increase the biodegradability of wastewaters is an important issue from the perspective of Green Chemistry. Copyright © 2010 John Wiley & Sons, Ltd.
Studies of gas‐phase reactions of cationic iron complexes of 2‐pyrimidinyloxy‐N‐arylbenzylamines by electrospray ionization tandem mass spectrometry
Authors: Xu Chu , Wang Hao‐Yang , Zhu Feng‐Jun , Guo Yin‐Long , Lu Long 
Published: December 2010

AbstractElectrospray ionization triple quadrupole mass spectrometry (ESI‐TSQ‐MS) and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI‐FTICR‐MS) were used to investigate the interesting gas‐phase reactions of the cationic iron (Fe) complexes of 2‐pyrimidinyloxy‐N‐arylbenzylamines (1–6), which are generated by ESI when mixing their methanolic solutions. Further studies of these Fe complexes by collision‐induced dissociation (CID) show that Fe(III) complexes undergo an interesting gas‐phase single electron transfer (SET) reaction to give 1•+–6•+,with loss of neutral FeCl2, whereas Fe(II) can catalyze gas‐phase Smiles rearrangement reactions of compounds 1–6. By using different Fe(II)X2 salts (X = Cl or Br) with a set of reactants, the role of the counterion (X−) and the structure effect of the reactants on Fe(II)‐catalyzed gas‐phase Smiles rearrangement reactions are studied. Evidence obtained from by TSQ‐MS and FTICR‐MS experiments, hydrogen/deuterium (H/D) exchange experiments and theoretical computations supported some unique gas‐phase chemistries initiated by introduction of Fe(II) into 1. Importantly, by comparing the distinct gas‐phase reaction results of the cationic Fe(III) complexes with those of Fe(II) complexes, the charge state effects of iron on the gas‐phase chemistries of Fe complexes are revealed. Copyright © 2010 John Wiley & Sons, Ltd.
Mass spectrometric characterization of photooxidative protein modifications in Arabidopsis thaliana thylakoid membranes
Authors: Galetskiy Dmitry , Lohscheider Jens N. , Kononikhin Alexey S. , Popov Igor A. , Nikolaev Eugene N. , Adamska Iwona 
Published: December 2010

AbstractOxidative and nitrosative stress leaves footprints in the plant chloroplast in the form of oxidatively modified proteins. Using a mass spectrometric approach, we identified 126 tyrosine and 12 tryptophan nitration sites in 164 nitrated proteolytic peptides, mainly from photosystem I (PSI), photosystem II (PSII), cytochrome b6/f and ATP‐synthase complexes and 140 oxidation products of tyrosine, tryptophan, proline, phenylalanine and histidine residues. While a high number of nitration sites were found in proteins from four photosynthetic complexes indicating that the nitration belongs to one of the prominent posttranslational protein modifications in photosynthetic apparatus, amino acid oxidation products were determined mostly in PSII and to a lower extent in PSI. Exposure of plants to light stress resulted in an increased level of tyrosine and tryptophan nitration and tryptophan oxidation in proteins of PSII reaction center and the oxygen‐evolving complex, as compared to low light conditions. In contrast, the level of nitration and oxidation of these amino acid residues strongly decreased for all light‐harvesting proteins of PSII under the same conditions. Based on these data, we propose that oxidative modifications of proteins by reactive oxygen and nitrogen species might represent an important regulatory mechanism of protein turnover under light stress conditions, especially for PSII and its antenna proteins. Copyright © 2010 John Wiley & Sons, Ltd.
Hydrogen isotope type‐curves of very hot crude oils
Authors: Fekete József , Sajgó Csanád , Demény Attila 
Published: December 2010

AbstractSeveral crude oil accumulations in the Pannonian Basin are trapped in uncommonly hot (>170°C) reservoirs. Their maturities range from mature to very mature on the basis of cracking parameters of their biological marker homologous series (ratio of products to reactants). A stable carbon isotopic study of these oils, poor in biological markers commonly used for correlation purposes, did not provide a reliable oil‐to‐oil correlation. As an alternative tool, the hydrogen isotope compositions of oil fractions separated on the basis of different polarities were measured, and hydrogen isotope type‐curves were generated for a set of mature to very mature crude oil samples. This method of presenting hydrogen isotope composition of fractions as type‐curves is novel.Nineteen samples (17 crude oils from SE‐Hungary, 1 oil condensate and 1 artificial oil) were chosen for the present study. The aim was to examine the applicability of hydrogen isotope type‐curves in oil‐to‐oil correlation and to test the simultaneous application of carbon and hydrogen isotope type‐curves in the field of petroleum geochemistry. We have shown that, although the conventionally used co‐variation plots proved to be inadequate for the correlation of these hot and mature oils, the simultaneous use of carbon and the newly introduced hydrogen isotope type‐curves allows us to group and distinguish oils of different origins. Copyright © 2010 John Wiley & Sons, Ltd.
Out of Sight, Out of Mind. Reporting of Three Indices in the UK National Press Between 1990 and 2009
Authors: Morse Stephen 
Published: December 2010

AbstractThis paper explores the reporting of three indices – the Corruption Perception Index (CPI), Human Development Index (HDI) and Ecological Footprint (EF) – in the national press of the UK between January 1990 and December 2009. The indices were compared over both time (year and month of article publication) and space (across the component countries of the UK and the Republic of Ireland, ROI). Results suggest that there are significant differences in reporting of the three indices. The EF appeared more frequently and was employed more often in articles than the CPI and HDI, perhaps reflecting a greater flexibility of the EF in terms of methodology and its association with consumption at all social scales, including the individual. The HDI was used by journalists more often as an ‘ornament’ to provide factual support to discussion of development, aid, conflict etc. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment.
Sensor network security for pervasive e‐health
Authors: Garcia‐Morchon Oscar , Falck Thomas , Wehrle Klaus 
Published: December 2010

ABSTRACTUbiquitous 24/7 health monitoring systems based on wireless medical sensors are going to play a key role for pervasive e‐health applications. These systems allow care givers to early detect and act on signs of patients' clinical deterioration improving quality of care in a reliable unobtrusive and cost effective way. Ensuring the privacy and security of the exchanged information is challenging in pervasive e‐health environments due to the resource constraints of tiny wireless medical sensors and operational requirements such as user mobility, strict latency needs, or the multitude of parties involved in the system. This paper describes a comprehensive and practical security framework for these pervasive health monitoring systems. We distinguish three layers addressing the specific security needs at the patient area network, medical sensor network, and back‐end levels. Thereby our architecture accommodates the healthcare institution‐centric approach predominant today while making provisions for the more patient‐centric vision of pervasive e‐health environments. The tailored security mechanisms for each individual layer as well as their interworking are presented and evaluated in detail. The analysis shows that our proposed security framework allows the deployment of wireless medical sensor networks in a very efficient way. Copyright © 2010 John Wiley & Sons, Ltd.
A VoIP system for mobility voice security support using the VPN
Authors: Kim Seok‐hun , Kim Soo‐Kyun , Park Jong Hyuk 
Published: December 2010

ABSTRACTVoice over internet protocol (VoIP) provided voice service using Internet. It receives footlights when it escapes an initial curiosity. Interest to VoIP increased, because it can transfer existing phone service and deliver voice data through Internet technology. Communication service providers introduce Next Generation Network and Broadband convergence Network with VoIP as an added service to the consumer. In addition, session initiation protocol (SIP) service can be applied even outside the Internet phone service. However, it is needed to ensure secrecy of VoIP call in a special situation. It is relatively difficult to eavesdrop in the commonly used Public Switched Telephone Network (PSTN) as it is connected with 1:1 circuit. In this paper, we propose a new model of Internet telephone for eavesdrop prevention enabling VoIP (using SIP protocol) to use the virtual private network (VPN) protocol and establish the probability of practical use comparing it with Internet telephone. Copyright © 2010 John Wiley & Sons, Ltd.