bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of high performance foams with excellent dielectric property based on toughened bismaleimide resin
Authors: Xie Xiaoqin , Gu Aijuan , Liu Ping , Liang Guozheng , Yuan Li
Published: February 2010

In order to meet the increasing demands on high performance foams with excellent dielectric property by modern industries, a new type of high performance foams based on diallyl bisphenol A modified bismaleimide (BDM/BA) resin is first developed in this paper. The effects of processing parameters such as prepolymerization time and temperature, foaming temperature and time as well as the content of blowing agent on the properties and morphology of resultant foams are intensively investigated from the view of processing–property–morphology relationship. Results show that compared with BDM/BA resin, the optimum condition of prepolymerization is 140°C for 60 min, and that of foaming is 160°C for 35 min. Foams based on BDM/BA resin with 9 wt% AC135 have uniform cell distribution, and greatly improved dielectric property. Copyright © 2010 John Wiley & Sons, Ltd.
Autophagy: assays and artifacts
Authors: Barth Sandra , Glick Danielle , Macleod Kay F
Published: February 2010

Autophagy is a fundamental and phylogenetically conserved self‐degradation process that is characterized by the formation of double‐layered vesicles (autophagosomes) around intracellular cargo for delivery to lysosomes and proteolytic degradation. The increasing significance attached to autophagy in development and disease in higher eukaryotes has placed greater importance on the validation of reliable, meaningful and quantitative assays to monitor autophagy in live cells and in vivo in the animal. To date, the detection of processed LC3B‐II by western blot or fluorescence studies, together with electron microscopy for autophagosome formation, have been the mainstays for autophagy detection. However, LC3 expression levels can vary markedly between different cell types and in response to different stresses, and there is also concern that over‐expression of tagged versions of LC3 to facilitate imaging and detection of autophagy interferes with the process itself. In addition, the realization that it is not sufficient to monitor static levels of autophagy but to measure ‘autophagic flux’ has driven the development of new or modified approaches to detecting autophagy. Here, we present a critical overview of current methodologies to measure autophagy in cells and in animals. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Driver mutations in TP53 are ubiquitous in high grade serous carcinoma of the ovary
Authors: Ahmed Ahmed Ashour , Etemadmoghadam Dariush , Temple Jillian , Lynch Andy G , Riad Mohamed , Sharma Raghwa , Stewart Colin , Fereday Sian , Caldas Carlos , deFazio Anna , Bowtell David , Brenton James D
Published: February 2010

Numerous studies have tested the association between TP53 mutations in ovarian cancer and prognosis but these have been consistently confounded by limitations in study design, methodology, and/or heterogeneity in the sample cohort. High‐grade serous (HGS) carcinoma is the most clinically important histological subtype of ovarian cancer. As these tumours may arise from the ovary, Fallopian tube or peritoneum, they are collectively referred to as high‐grade pelvic serous carcinoma (HGPSC). To identify the true prevalence of TP53 mutations in HGPSC, we sequenced exons 2–11 and intron–exon boundaries in tumour DNA from 145 patients. HGPSC cases were defined as having histological grade 2 or 3 and FIGO stage III or IV. Surprisingly, pathogenic TP53 mutations were identified in 96.7% (n = 119/123) of HGPSC cases. Molecular and pathological review of mutation‐negative cases showed evidence of p53 dysfunction associated with copy number gain of MDM2 or MDM4, or indicated the exclusion of samples as being low‐grade serous tumours or carcinoma of uncertain primary site. Overall, p53 dysfunction rate approached 100% of confirmed HGPSCs. No association between TP53 mutation and progression‐free or overall survival was found. From this first comprehensive mapping of TP53 mutation rate in a homogeneous group of HGPSC patients, we conclude that mutant TP53 is a driver mutation in the pathogenesis of HGPSC cancers. Because TP53 mutation is almost invariably present in HGPSC, it is not of substantial prognostic or predictive significance. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Autophagy: cellular and molecular mechanisms
Authors: Glick Danielle , Barth Sandra , Macleod Kay F.
Published: February 2010

Autophagy is a self‐degradative process that is important for balancing sources of energy at critical times in development and in response to nutrient stress. Autophagy also plays a housekeeping role in removing misfolded or aggregated proteins, clearing damaged organelles, such as mitochondria, endoplasmic reticulum and peroxisomes, as well as eliminating intracellular pathogens. Thus, autophagy is generally thought of as a survival mechanism, although its deregulation has been linked to non‐apoptotic cell death. Autophagy can be either non‐selective or selective in the removal of specific organelles, ribosomes and protein aggregates, although the mechanisms regulating aspects of selective autophagy are not fully worked out. In addition to elimination of intracellular aggregates and damaged organelles, autophagy promotes cellular senescence and cell surface antigen presentation, protects against genome instability and prevents necrosis, giving it a key role in preventing diseases such as cancer, neurodegeneration, cardiomyopathy, diabetes, liver disease, autoimmune diseases and infections. This review summarizes the most up‐to‐date findings on how autophagy is executed and regulated at the molecular level and how its disruption can lead to disease. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Pharmacoepidemiological research using French reimbursement databases: yes we can!
Authors: Martin‐Latry Karin , Bégaud Bernard
Published: February 2010

Purpose

To describe the reimbursement databases available in France for pharmacoepidemiological research and their use.

Methods

France has a publicly funded health system that systematically covers the population. Within this system, three main insurance schemes provide health services to citizens in France and each have their own reimbursement database. Together these three databases cover almost 97% of the French population (respectively for 54.5, 3.6, and 3.3 million individuals, and a total of 61.4 million individuals). Data in these concern patients, prescribers, all the medical acts reimbursed, prescription and undertaking of laboratory tests (but without results), private hospital data, partial public hospital data and vital status. Their use is regulated but access is free and the data are anonymous. PubMed and Scopus were searched for relevant studies published from January 1988 to June 2009.

Results

110 published studies were included. The topics and the study characteristics were extremely wide‐ranging. The studies assessed patterns of drug use, have tested interventions, supported or improved prescribing practices, tested compliance with the French governmental Health guidelines, assessed physicians' prescribing practices and performed economic and cost‐effectiveness assessments. The number of articles published increased greatly between 2002 and 2003.

Conclusions

The French reimbursement databases were greatly used over the last 20 years. They can provide data on exposure to drugs and can be used to study patterns of drug utilization although their limitations must be considered. Copyright © 2010 John Wiley & Sons, Ltd.
Influence of imidazolium‐based ionic liquids on the performance of ionic polymer conductor network composite actuators
Authors: Liu Sheng , Liu Wenjuan , Liu Yang , Lin Jun‐Hong , Zhou Xin , Janik Michael J , Colby Ralph H , Zhang Qiming
Published: February 2010

We investigated the influence of ionic liquids (ILs) on the electromechanical performance of ionic polymer conductor network composite (IPCNC) actuators. Four imidazolium ILs with two cations of different sizes, i.e. 1‐ethyl‐3‐methylimidazolium ([EMI+]) and 1‐butyl‐3‐methylimidazolium ([BMI+]), and two anions of different sizes, i.e. tetrafluoroborate ([BF4−]) and trifluoromethanesulfonate ([Tf−]), were used. The IPCNC actuators were fabricated using a direct assembly method with RuO2/Nafion® nanocomposite as the electrode layers. The experimental results reveal that the actuator strain response time is nearly one order of magnitude shorter than the charging time. The IPCNCs with [EMI+][Tf−] exhibit the highest capacitance and the fastest response in both actuation and electrical charging as capacitors. In contrast, the IPCNCs with [EMI+][BF4−] display the slowest charging time and lowest value of capacitance as capacitors. The IPCNCs with [BMI+][BF4−] show the slowest response time. Furthermore, although the ILs used have a marked effect on the capacitances of the IPCNCs, using different ILs does not cause much change in the maximum strain of these IPCNCs. Consequently, the IPCNC actuators with [EMI+][BF4−] show the highest electromechanical conversion efficiency while those with [EMI+][Tf−] have the lowest electromechanical efficiency because of the highest capacitance and largest input electrical energy. The experimental results indicate that the two oppositely charged ions contribute in opposite manner to the strain response and hence the observed shorter actuation response time is likely caused by the strain cancellation effect between the cations and anions. Copyright © 2010 Society of Chemical Industry
Surface‐initiated atom transfer radical polymerization of regenerated cellulose membranes with thermo‐responsive properties
Authors: Pan Kai , Zhang Xiaowei , Cao Bing
Published: February 2010

Using atom transfer radical polymerization (ATRP), thermo‐responsive regenerated cellulose membranes were synthesized. Regenerated cellulose membranes were firstly modified by reacting the hydroxyl groups on the surface with 2‐bromoisobutyryl bromide, followed by grafting with poly(N‐isopropylacrylamide). The membranes had obvious thermally modulated permeability properties. Analysis was carried out by means of X‐ray photoelectron spectroscopy, attenuated total reflection Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis. The results showed that N‐isopropylacrylamide had been grafted successfully on the surface of the regenerated cellulose membranes. The thermally modulated permeability properties of the grafted membranes were studied using water flux measurements. It was found that the thermally modulated permeability properties of a cellulose surface can be tailored by the use of the ATRP method. Copyright © 2010 Society of Chemical Industry
Synthesis and characterization of fluorinated polyacrylate–cellulose acetate butyrate interpenetrating polymer networks
Authors: Darras Vincent , Peralta Sébastien , Boileau Sylvie , Teyssié Dominique , Fichet Odile
Published: February 2010

Fluorinated polyacrylates are highly hydrophobic and oleophobic. However, their poor mechanical properties prevent their development in many applications. Combination of a fluorinated polyacrylate network with a rigid cellulose acetate butyrate (CAB) network in an interpenetrating polymer network (IPN) architecture is an effective method for improving the mechanical properties of fluorinated polyacrylates. IPNs combining poly(3,3,4,4,5,5,6,6,7,7,8,8,8‐tridecafluorooctyl acrylate) (polyAcRf6) with CAB were prepared according to an in situ polymerization/crosslinking synthesis. CAB was crosslinked by addition between unmodified hydroxyl groups and the isocyanate of a pluri‐isocyanate crosslinker. The fluorinated network was obtained through free‐radical copolymerization of 3,3,4,4,5,5,6,6,7,7,8,8,8‐tridecafluorooctyl acrylate with poly(ethylene glycol dimethacrylate). The rates of formation of both networks were followed using Fourier transform infrared spectroscopy. Differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) of IPNs show a single glass transition temperature and a single mechanical relaxation temperature, which are characteristic of a high degree of interpenetration between the partner networks. The mechanical properties of IPNs are greatly improved compared with those of the single fluorinated network. CAB/polyAcRf6 IPNs were prepared, and characterized using DSC and DMTA as well as contact angle measurements for their surface properties. As hoped, the mechanical properties of such materials are much improved compared with those of the fluorinated partner alone. Copyright © 2010 Society of Chemical Industry
Gilthead sea bream liver proteome altered at low temperatures by oxidative stress
Authors: Ibarz Antoni , Martín‐Pérez Miguel , Blasco Josefina , Bellido David , de Oliveira Eliandre , Fernández‐Borràs Jaume
Published: February 2010

Gilthead sea bream exposed to the cold show multiple physiological alterations, particularly in liver. A typical cold‐stress response was reproduced in gilthead sea bream acclimated to 20°C (Warm group) when the water temperature was lowered to 8°C (Cold group). After 10 days, thiobarbituric acid reactive substances in the liver had increased by 50%, and nitric oxide had increased twofold. This indicates that lipid peroxidation and oxidative stress had occurred. Protein profiles of liver from fish in warm and cold environments were obtained by 2‐DE. Quantification of differential expression by matching spots showed that a total of 57 proteins were altered significantly. Many proteins were downregulated following cold exposure, including actin, the most abundant protein in the proteome; enzymes of amino acid metabolism; and enzymes with antioxidant capacity, such as betaine‐homocysteine‐methyl transferase, glutathione‐S‐transferase and catalase. Some proteins associated with protective action were upregulated at low temperatures, including peroxiredoxin, thioredoxin and lysozyme; as well as enzymes such as aldehyde dehydrogenase and adenosin‐methionine synthetase. However, the upregulation of proteases, proteasome activator protein and trypsinogen‐like protein indicated an increase in proteolysis. Increases in elongation factor‐1α, the GAPDH oxidative form, tubulin and Raf‐kinase inhibitor protein indicated oxidative stress and the induction of apoptosis. These data indicate that cold exposure induced oxidative damage in hepatocytes.
9‐Azidoacridine and 9‐acridinylnitrene
Authors: Taherpour Avat Arman , Kvaskoff David , Bernhardt Paul V. , Wentrup Curt
Published: February 2010

Matrix photolysis as well as flash vacuum thermolysis (FVT) of 9‐azidoacridine affords 9‐acridinylnitrene, which is characterized by its IR and ESR spectra and is photochemically inert. FVT above 600 °C yields a mixture of the five isomeric cyanocarbazoles. Microwave‐assisted reaction with diethyl‐ and dipropylamines in solution affords acridinylformamidine and acridinylpropionamidine, respectively. Microwave‐assisted reaction with dimethylamine causes nucleophilic displacement of the azido group. Microwave‐assisted 1,3‐dipolar cycloaddition with phenylacetylene yields the two regioisomeric 9‐(4‐ and 5‐phenyl‐1,2,3‐triazol‐1‐yl)acridines, whose structures were established by X‐ray crystallography. Copyright © 2010 John Wiley & Sons, Ltd.
Metal‐free synthesis of responsive polymers: Cloud point tuning by controlled “click” reaction
Authors: Becer C. Remzi , Kokado Kenta , Weber Christine , Can Aydin , Chujo Yoshiki , Schubert Ulrich S.
Published: February 2010

Nitroxide‐mediated radical polymerization has been used for the preparation of pentafluorostyrene (PFS) homopolymers and random copolymers of PFS and oligo(ethyleneglycol) methacrylate (OEGMA8.5). The poly(pentafluorostyrene) homopolymers were reacted with thiophenol at different ratios at room temperature in the presence of triethylamine. The “clicked” polymers were characterized by 1H and 19F NMR spectroscopy and size exclusion chromatography. Moreover, the copolymerization kinetics of the PFS and OEGMA8.5 copolymers was followed, and the phase transition behavior of random copolymers with different compositions was discussed. Furthermore, copolymers of PFS and 2‐(dimethylamino) ethyl methacrylate (DMAEMA) were prepared at various mole ratios, and the copolymer with a 10:90 ratio, respectively, was soluble in water at room temperature. Turbidimetry measurements were performed for PFS and OEGMA8.5 or DMAEMA copolymers to determine their cloud points. Finally, the PFS and OEGMA8.5 copolymer with a mole ratio of 60:40 was reacted further with thiophenol to increase the hydrophobic part in the copolymer. The cloud points of the obtained copolymers could be tuned from 87 to 33 °C by using not only the controlled radical polymerization but also the “click” reaction in a controlled fashion. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1278–1286, 2010
Synthesis and characterization of donor–bridge–acceptor alternating copolymers containing perylene diimide units and their application to photovoltaic cells
Authors: Yuan Mao‐Chuan , Su Ming‐Hsin , Chiu Mao‐Yuan , Wei Kung‐Hwa
Published: February 2010

We have used Suzuki coupling to prepare a series of alternating copolymers featuring coplanar cyclopentadithiophene and hole‐transporting carbazole units. We observed quenching in the photoluminescence spectra of our polymers after incorporating pendent electron‐deficient perylene diimide (PDI) moieties on the side chains, indicating more efficient photoinduced electron transfer. Electrochemical measurements revealed that the PDI‐containing copolymers displayed reasonable and sufficient offsets of the energy levels of their lowest unoccupied molecular orbitals for efficient charge dissociation. The performance of bulk heterojunction photovoltaic cells incorporating the copolymer/[6,6]‐phenyl‐C61‐butyric acid methyl ester blends (1:4, w/w) was optimized when the active layer had a thickness of 70 nm. The photocurrents of the devices were enhanced as a result of the presence of the PDI moieties, thereby leading to improved power conversion efficiencies. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1298–1309, 2010
Synthesis and properties of crosslinked chiral nanoparticles via RAFT miniemulsion polymerization
Authors: Xu Wenliang , Cheng Zhenping , Zhang Lifen , Zhang Zhengbiao , Zhu Jian , Zhou Nianchen , Zhu Xiulin
Published: February 2010

Crosslinked chiral nanoparticles were successfully synthesized via reversible addition‐fragmentation chain transfer (RAFT) miniemulsion polymerization of 6‐O‐p‐vinylbenzyl‐1,2:3,4‐di‐O‐isopropylidene‐D‐galactopyranose (VBPG) using linear poly(VBPG) as the macro‐RAFT agent. The polymerization of VBPG in the absence of crosslinker was first studied and the kinetic results showed that the molecular weights of the obtained poly(VBPG) increased linearly with the monomer conversion and was in good consistency with the corresponding theoretical ones while there remained a relative narrow polydispersity. The effect of the amount of crosslinker, divinylbenzene, on the nanoparticle size and chiral separation properties of the obtained nanoparticles were investigated in detail using four racemates ±‐3‐Amino‐1,2‐propanediol, D,L‐arabinose, D,L‐tartaric acid, and D,L‐mandelic acid. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1324–1331, 2010
Flexible nanocrystalline‐titania/polyimide hybrids with high refractive index and excellent thermal dimensional stability
Authors: Liou Guey‐Sheng , Lin Po‐Han , Yen Hung‐Ju , Yu Yang‐Yen , Chen Wen‐Chang
Published: February 2010

In this study, a novel synthetic route was developed to prepare polyimide–nanocrystalline–titania hybrid optical films with a relatively high titania content (up to 50 wt %) and thickness (20–30 μm) from soluble polyimides containing hydroxyl groups. Two series of newly soluble polyimides were synthesized from the hydroxy‐substituted diamines with various commercial tetracarboxylic dianhydrides. The hydroxyl groups on the backbone of the polyimides could provide the organic–inorganic bonding and resulted in homogeneous hybrid solutions by controlling the mole ratio of titanium butoxide/hydroxyl group. AFM, SEM, TEM, and XRD results indicated the formation of well‐dispersed nanocrystalline‐titania. The flexible hybrid films could be successfully obtained and revealed relatively good surface planarity, thermal dimensional stability, tunable refractive index, and high optical transparency. A three‐layer antireflection coating based on the hybrid films was prepared and showed a reflectance of less than 0.5% in the visible range indicated its potential optical applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1433–1440, 2010
A novel type of optically active helical polymers: Synthesis and characterization of poly(α,β‐unsaturated ketone)
Authors: Wu Shi , Yang Nianfa , Yang Liwen , Cao Jing , Liu Ji
Published: February 2010

New α,β‐unsaturated ketone monomers, menthyl vinyl ketone (MVK), and 1‐menthylbut‐3‐en‐2‐one (MBEK) were synthesized. The monomers were polymerized using butyllithium as an initiator. The polymer derived from MVK (poly‐MVK) had a tremendous specific optical rotation [α], which was as 32 times large as that of its monomer MVK. Poly‐MVK was confirmed to keep a prevailing helicity of backbone in solution by means of comparing the specific optical rotation and the CD spectra with that of MVK and the model compound such as ethyl menthyl ketone (EMK) and n‐hexyl menthyl ketone (n‐HMK). This conclusion was also confirmed by the fact that the specific optical rotation and the CD signal intensity of poly‐MBEK were not enough large due to backbone flexibility caused by the effective isolation of the main chain from the bulky menthyl. The excess value of one‐handed helicity of poly‐MVK decreased with the increase of polymerization temperature. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1441–1448, 2010
Nucleation characteristics of the α/β compounded nucleating agents and their influences on crystallization behavior and mechanical properties of isotactic polypropylene
Authors: Zhao Shicheng , Xin Zhong
Published: February 2010

Nucleation characteristics of isotactic polypropylene (iPP) nucleated by the α/β compounded nucleating agents (NAs) were investigated by wide‐angle X‐ray scattering, differential scanning calorimetry and mechanical testing. The results showed that the nucleation effect of the α/β compounded NAs depends on not only nucleation efficiency (NE) of individual β and α NAs and their ratios but also the processing conditions, especially the cooling rates. The nucleating characteristics of the α/β compounded NAs can be illustrated by competitive nucleation. The NA with high NE played a leading role during iPP crystallization even at a low weight ratio and at different cooling rates. The stiffness and toughness of iPP can be simultaneously improved by using suitable compositions at the appropriate ratios. Finally, the nonisothermal crystallization kinetics of iPP nucleated with the α/β compounded NAs was described by Caze method and the crystallization activation energy of nucleated iPP was calculated by Kissinger equation. The result indicated that the crystal growth pattern of nucleated iPP was heterogeneous nucleation followed by three‐dimension spherical growth. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 653–665, 2010
Synthesis and comparative study of biodegradable poly(alkylene sebacate)s
Authors: Papageorgiou George Z. , Bikiaris Dimitrios N. , Achilias Dimitris S. , Nanaki Stavroula , Karagiannidis Nikitas
Published: February 2010

Novel biodegradable polyesters, such as poly(ethylene sebacate) (PESeb), poly(propylene sebacate) (PPSeb), and poly(butylene sebacate) (PBSeb), were synthesized and studied with respect to melting behavior, crystallization kinetics, and enzymatic hydrolysis. PESeb and PPSeb showed multiple melting behavior. Wide angle X‐ray diffractometry measurements at various temperatures, standard, step‐scan, and high‐rate differential scanning calorimetry methods were applied to elucidate the appearance of multiple endotherms in heating scans, which was interpreted in the context of partial melting‐recrystallization and final melting. PBSeb did not show any multiple melting behavior but only a weak tendency for recrystallization on heating. The melting temperatures of PESeb, PPSeb, and PBSeb were measured equal to 78, 57, and 71 °C, respectively. The equilibrium melting points were estimated to be Tm° = 90.2, 69.9, and 77.4 °C for PESeb, PPSeb, and PBSeb, while the corresponding enthalpy of fusion values were found to be ΔHf = 170 ± 10, 140 ± 10, and 155 ± 10 J/g, respectively. The polyesters showed fast crystallization rates under both isothermal and nonisothermal conditions. Crystallization kinetics was thoroughly investigated using macrokinetic models and isoconversional analysis. Enzymatic hydrolysis rate in the presence of lipases Rhizopus delemar and Pseudomonas cepacia was found to be fast for PPSeb, whereas PESeb and PBSeb showed slow rates and comparable with those of PCL. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 672–686, 2010
Associations of tonsillar hypertrophy and snoring with history of wheezing in childhood
Authors: Kaditis Athanasios G. , Kalampouka Efthimia , Hatzinikolaou Souzana , Lianou Loukia , Papaefthimiou Maria , Gartagani‐Panagiotopoulou Polytimi , Zintzaras Elias , Chrousos George
Published: February 2010

Background

Reports in adults and children have correlated history of wheezing or asthma with the presence of obstructive sleep‐disordered breathing but the mechanism of this epidemiologic association is unknown. The goal of the present study was to examine whether tonsillar hypertophy can explain this association.

Methods

Children were recruited from the Emergency Department and the Pediatric Pulmonology Clinic. History of wheezing requiring treatment (explanatory variable) and snoring ≥1 night/week (outcome) were recorded and presence of tonsillar hypertrophy (outcome) was assessed.

Results

Four hundred forty‐two children were recruited (mean age: 7.6 ± 3.6 years) and 210 of them had history of wheezing. History of wheezing was significantly associated with the presence of tonsillar hypertrophy and snoring even after adjustment for age, gender, obesity, and passive smoking [odds ratio (95% confidence interval): 2.23 (1.37–3.63); P = 0.001 and 1.73 (1.12–2.67); P = 0.013, respectively]. When only children with tonsillar hypertrophy were considered (n = 92), history of wheezing was significantly related to the presence of snoring, whereas in subjects without tonsillar hypertrophy (n = 350) wheezing did not affect snoring [odds ratio: 2.76 (1.10–6.93); P = 0.031 and 1.49 (0.92–2.43); P = 0.107, respectively].

Conclusions

Children with history of wheezing have more frequently tonsillar hypertrophy than those without wheezing. Tonsillar hypertrophy may mediate at least in part the reported association between asthma and obstructive sleep‐disordered breathing in childhood. Pediatr Pulmonol. 2010; 45:275–280. © 2010 Wiley‐Liss, Inc.
Liver proteins as sensor of human malignancies and inflammation
Authors: Peracaula Rosa , Sarrats Ariadna , Rudd Pauline M.
Published: February 2010

In this review we would like to highlight the importance of acute‐phase proteins as sensor of diseases. Both acute‐phase protein levels and glycosylation have been reported to be altered in inflammation and other diseases including cancer. Factors that promote acute‐phase protein synthesis and enhance the expression of specific glycosyltransferases, such as sialyltransferases and fucosyltransferases, may be up‐regulated in some tumours and would explain the changes in acute‐phase protein levels and the specific N‐glycosylation modifications of some acute‐phase proteins in cancer. However, further studies are required to define the potential clinical application of these acute‐phase protein cancer‐specific modifications as possible cancer diagnostic or monitoring tools.
Structural investigation of transcriptional regulator HlyIIR: Influence of a disordered region on protein fold and dimerization
Authors: Kovalevskiy Oleg V. , Solonin Alexander S. , Antson Alfred A.
Published: February 2010

B. cereus HlyIIR belongs to the TetR family of dimeric transcriptional regulators. Unlike other members of the TetR family, HlyIIR contains an insert between α‐helices α8 and α9, which is located at the subunit–subunit interface. N‐terminal segment of this insert (amino acids, Pro161–Ser169) forms a short α‐helix α8* that occupies a complementary cavity on the surface of the adjacent subunit, whereas the C‐terminal segment comprising 16 amino acids (Leu170–Glu185) is disordered. To understand whether this disordered segment is important for protein's function, we determined crystal structures of two engineered HlyIIR proteins where this segment was either substituted by a seven‐residue flexible Ser‐Gly linker or replaced by a cleavable peptide containing proteolytic sites at both ends. Unexpectedly, alteration or proteolytic removal of the disordered segment resulted in changes in protein's conformation and in a remarkable rearrangement at the subunit–subunit interface. X‐ray structures of the two engineered proteins revealed an unusual plasticity at the dimerization interface of HlyIIR enabling it to form dimers stabilized by different sets of interactions. Structural comparison indicates that in spite of the flexible nature of the disordered segment, it is critical for maintaining the native structure as it influences the position of α8*. The data demonstrate how disordered loops on protein surfaces may affect folding and subunit–subunit interactions. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Selective cleavage of an azaGly peptide bond by copper(II). Long‐range effect of histidine residue
Authors: Mhidia Reda , Melnyk Oleg
Published: February 2010

Several reports have highlighted the interest of replacing Gly, a frequent amino acid within bioactive peptides, by azaGly (Agly) to improve their stability, activity or for the design of prodrugs. Because metal catalysis is increasingly used for tailoring peptide molecules, we have studied the stability of Agly peptides in the presence of metal ions. In this study, we show that Cu(II), unlike other metal ions such as Fe(II), Fe(III), Pd(II), or Pt(II), induces the cleavage of Agly peptides at room temperature and pH 7.3. The cleavage occurred in the absence of an anchoring His residue within the peptide but it was accelerated when this amino acid was present in the sequence. The influence of His residue on the cleavage rate was minimal when His and Agly were adjacent, whereas large effects were observed for distant His residues. The reaction between Cu(II) and Agly peptides induced the formation of Cu(I) species, which could be detected using bicinchoninic acid as a probe. The nature of products formed in this reaction allowed suggesting a mechanism for the Cu(II)‐induced cleavage of Agly peptides. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Problem‐based learning approach to application of statistical experimentation
Authors: Goh T. N. , Lam S. W.
Published: February 2010

In product development, statistical experimentation techniques can help to improve product quality so as to meet or even exceed customers' requirements. To integrate proper statistical techniques effectively and sustainably into new product development and innovation processes, it is important to train product development engineers who are usually experts in their respective engineering domain. In this paper, a problem‐based learning approach integrated within a Design for Six Sigma (DFSS) training program is described. It is illustrated that instead of relying on ad hoc implementation, statistical experimentation introduced through the DFSS methodology would enable product development engineers to appreciate its usefulness within a broader framework. Copyright © 2010 John Wiley & Sons, Ltd.
On monitoring process variance with individual observations
Authors: Yeh Arthur B. , Huwang Longcheen , McGrath Richard N. , Zhang Zhe
Published: February 2010

This paper proposes a new control chart to effectively monitor the decrease in variance of a normal process when only individual observations are available. The idea of the new control chart, which is called the exponentially weighted mean squared inverse error (EWMSI) chart, stems from the exponentially weighted mean squared error (EWMS) chart of MacGregor and Harris (J. Qual. Technol. 1993; 25(2):106–118). Simulation studies and an example demonstrate that the lower‐sided EWMSI chart is superior to the lower‐sided EWMS chart and the lower‐sided modified EWMS (M‐EWMS) chart of Huwang et al. (Nav. Res. Logist. 2009; 56(7):659–668) in detecting a decrease in process variance. Furthermore, the combination of a lower‐sided EWMSI chart and an upper‐sided EWMS chart is shown to outperform the two‐sided EWMS chart and the two‐sided M‐EWMS chart in monitoring the overall changes in process variance. Copyright © 2010 John Wiley & Sons, Ltd.
Guidelines for the placement of fiducial points in image‐guided neurosurgery
Authors: Wang Manning , Song Zhijian
Published: February 2010

Background

Point‐pair registration is widely used to register the patient and the image space in image‐guided neurosurgery. The registration accuracy at the target point is influenced by the distribution of the fiducial points, and it is not always easy to achieve a good distribution in clinical practice.

Methods

We propose one original configuration and three variants of the distribution of the fiducial points, in which each fiducial point has a definite position on the head surface. These configurations are conceived by considering both the theoretical value of the target registration error (TRE) and practical constraints on the positioning of the fiducial points. These configurations can guide the surgeon to place fiducial points directly onto the patient's head.

Results

Experiments with real clinical data showed that when using the original configuration, the TRE in the whole skull was < 2 mm and the TRE in the whole brain was < 1.5 mm if the fiducial registration error was 2.5 mm. When using variants of the original configuration, small TRE can also be achieved in the corresponding surgical field.

Conclusions

This study provides an easy‐to‐use approach to achieving good distribution of fiducial points in image‐guided neurosurgery. Copyright © 2010 John Wiley & Sons, Ltd.
Downstream environmental effects of dam operations: Changes in habitat quality for native fish species
Authors: García Alex , Jorde Klaus , Habit Evelyn , Caamaño Diego , Parra Oscar
Published: February 2010

Hydropeaking dam operation and water extractions for irrigation have been broadly stated as alterations to natural flow regimes, which have also been noticed in the Biobío Watershed, in Central Chile, since 1996. In the Biobío River, most of native fish species are endemic and very little is known about them. Their ecological and social values have never been estimated, and there is lack of information about their habitat preferences. Furthermore, changes on fish habitat availability due to natural and/or man‐made causes have not been evaluated. In this study, eight native fish species, in a representative reach of the Biobío River, were studied and their preferred habitats were surveyed and characterized. A hydrodynamic model was built and linked to the fish habitat simulation model CASiMiR. Fuzzy rules and fuzzy sets were developed for describing habitat preference of the native fish species. CASiMiR was then used to simulate how physical habitat conditions vary due to flow control (i.e. upstream dams). Results show how overall habitat quality, expressed as weighted usable area (WUA) and hydraulic habitat suitability (HHS), changes and fluctuates due to the dam operation and how the daily hydropeaking is influencing quantity, quality and location of different habitats. The study suggests that the analysed fish are highly susceptible to flow control, as dams are currently operated, and fish habitat improvement suggestions are proposed. Copyright © 2010 John Wiley & Sons, Ltd.
Automatic detection and replacement of syntactic constructs causing shift/reduce conflicts
Authors: Kramer Thomas R.
Published: February 2010

A method is described for repairing some shift/reduce conflicts caused by limited lookahead in LALR(1) parsers such as those built by bison. Also, six types of Extended BNF (EBNF) construct are identified that cause a shift/reduce conflict when a Yet Another Compiler Compiler (YACC) file translated directly from EBNF is processed by bison. For each type, a replacement EBNF construct is described representing the same grammar and causing no shift/reduce conflict when its YACC equivalent is processed by bison. Algorithms are given for identifying instances of each type and transforming them into their replacements. The algorithms are implemented in an automatic parser builder that builds parsers for subsets of the DMIS language. The parser builder reads an EBNF file and writes C++ classes, a YACC file, and a Lex file, which are then processed to build a parser. The parsers build a parse tree using the C++ classes. The EBNF for DMIS is written in natural terms so that natural C++ classes are generated. However, if translated directly into YACC, the natural EBNF leads to 22 shift/reduce conflicts that fall into the six types. The parser builder recognizes the six constructs and replaces them automatically before generating YACC. The YACC that is generated parses in terms of unnatural constructs while building a parse tree using natural C++ classes. The six types of construct may occur in any statement‐based language that uses a minor separator, such as a comma; hence knowing how to recognize and replace them may be broadly useful. Published in 2010 by John Wiley & Sons, Ltd.
Growth of fetal lean mass and fetal fat mass in gestational diabetes
Authors: Nobile de Santis M. S. , Taricco E. , Radaelli T. , Spada E. , Rigano S. , Ferrazzi E. , Milani S. , Cetin I.
Published: February 2010

Objectives

This study was carried out to investigate growth indicators of fetal lean mass and fat mass in the second half of the gestational period in pregnancies complicated by gestational diabetes mellitus (GDM) in comparison to normal control pregnancies.

Methods

Forty‐three control and 171 GDM pregnancies were followed longitudinally by ultrasound examinations, measuring both traditional biometric parameters and six non‐traditional parameters for the evaluation of lean and fat mass. A mixed linear model derived from the log‐Count function was used to model fetal growth and to make comparisons between groups. Factor analysis was used to evaluate the associations between gestational diabetes and fetal size and fetal fat/lean mass ratios.

Results

A total of 506 scans were obtained in the 214 pregnancies, a mean of 2.4 scans per pregnancy (range 2–5). Maternal age, prepregnancy weight and body mass index were significantly higher in GDM pregnancies. Fetuses of GDM pregnancies showed greater growth, at the same gestational age, for each lean and fat non‐traditional parameter, having a significantly greater amount of total tissue mass and a higher fat mass/lean mass ratio, independent of gestational age, in comparison to control pregnancies.

Conclusions

A non‐invasive, repeatable evaluation of fetal body composition in utero could represent a useful method for the early detection of growth abnormalities and for direct estimation of the fetal metabolic status. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Fetal thymus size in uncomplicated twin and singleton pregnancies
Authors: Gamez F. , De Leon‐Luis J. , Pintado P. , Perez R. , Robinson J. N. , Antolin E. , Ortiz‐Quintana L. , Santolaya‐Forgas J.
Published: February 2010

Objectives

The main objective of this study was to determine whether fetal thymic measurements could be obtained in twins, with a secondary goal to determine whether thymic measurements from uncomplicated singleton and twin pregnancies are comparable.

Methods

The transverse diameter and perimeter of the fetal thymus were measured prospectively in 678 singleton and 56 twin pregnancies, and their relationships with gestational age were determined and compared between groups.

Results

Thymic measurements were possible in 757 (95.8%) of the 790 fetuses. Measurements were not possible in 19 of 678 singletons (2.8%) and in 14 of the 112 (12.5%) twins (P < 0.001). After construction of nomograms for the transverse diameter and perimeter of the fetal thymus, similar measurements were noted for singletons and twins.

Conclusions

These results suggest that sonographic measurements of the thymus are feasible in twin pregnancies and that, in uncomplicated pregnancies, these measurements are similar to those noted for singletons. These findings pave the way for future studies aimed at determining the clinical utility of thymic measurements in complicated singleton and twin pregnancies. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Surgeon‐Performed Ultrasound in Patients Referred for Thyroid Disease Improves Patient Care by Minimizing Performance of Unnecessary Procedures and Optimizing Surgical Treatment
Authors: Mazzaglia Peter J.
Published: February 2010

Background

Ultrasonography has become an indispensable tool in the evaluation of thyroid nodular disease, and most patients will have had a thyroid ultrasound prior to initial surgical evaluation. This study examines the added benefit of office‐based, surgeon‐performed ultrasonography in patients referred for thyroid disease.

Methods

All patients referred to a single endocrine surgeon for evaluation of thyroid disease over a 2‐year period were reviewed. Outside ultrasonographic findings were compared to the surgeon‐performed ultrasound that was used to formulate treatment decisions.

Results

Of 286 consecutive patients referred for surgical evaluation of thyroid disease, 261 had an outside ultrasound available for comparison. There were 239 women and 47 men. Mean age was 54.7 ± 16.6. In 46 patients (17.6%), differences between the two ultrasounds were significant enough to alter treatment plans. For 18 patients no distinct nodule was identified and biopsy was avoided. Nine of these patients had ultrasound characteristics of Hashimoto’s disease. In five patients the nodule was significantly smaller than reported and biopsy was not warranted. Twelve patients had nonpalpable, enlarged lymph nodes not previously identified; these were biopsied. Three were positive for metastatic thyroid cancer, which prompted the addition of neck dissection to the operative procedure. In 8 of 132 patients undergoing thyroidectomy, the surgical procedure was significantly altered by the ultrasound findings.

Conclusions

This study demonstrates a clear advantage for patients who undergo a surgeon‐performed ultrasound. For many, unnecessary procedures were prevented. For others, substantial modifications to the extent of surgery were made when new ultrasonographic findings were identified during the preoperative investigation.
Impact of Prophylactic Central Neck Lymph Node Dissection on Early Recurrence in Papillary Thyroid Carcinoma
Authors: Moo Tracy‐Ann , McGill Julie , Allendorf John , Lee James , Fahey Thomas , Zarnegar Rasa
Published: February 2010

Background

Although the role of prophylactic central neck lymph node dissection (CNLD) in the treatment of papillary thyroid carcinoma (PTC) is controversial, many surgeons perform routine prophylactic CNLD. The present study compares local recurrence rates in PTC patients undergoing total thyroidectomy with and without prophylactic CNLD.

Materials and Methods

A retrospective review of 206 patients undergoing thyroidectomy for PTC was conducted at two tertiary referral centers. Of these, 81 patients had total thyroidectomy for PTC and a follow‐up between 2 and 9 years with a mean of 3.1 years. Of these 81 patients, 45 underwent routine prophylactic CNLD and 36 did not. For those two groups, demographics, clinical and pathologic findings, radioactive iodine (RAI) treatment, and the incidence of recurrence were compared. Univariate statistical analysis was performed.

Results

There was no significant difference in age, gender, multifocality, or extrathyroidal extension for the two groups. Patients with CNLD had an average tumor size of 1.4 cm versus 2 cm in the group without CNLD (p < 0.05). Patients who underwent CNLD had an average of 8 nodes removed, and positive nodes were found in 33%. Patients with CNLD received a higher dose of RAI, 102.7 mCi versus 66.3 mCi (p < 0.05). The incidence of positive nodes correlated with an increased RAI dose (r = 0.55). Rates of parathyroid removal and autotransplantation were higher in the CNLD group, 36 and 16% in the CNLD group versus 22 and 3% in the group without CNLD (p = 0.4 and p = 0.07). Rates of temporary hypocalcemia were higher in the CNLD group (31 versus 5%; p = 0.001), however rates of permanent hypocalcemia were similar, 1/35 in the no CNLD group versus 0/45 in the CNLD group (p = 0.4). There was a higher recurrence rate among patients without CNLD 6/36 (16.7%) versus 2/45 (4.4%), although this difference was not statistically significant (p = 0.13).

Conclusions

Routine CNLD as an adjunct to total thyroidectomy identifies positive nodes in over 30% of patients with PTC. The discovery of positive nodes is associated with higher doses of RAI for postoperative ablation, and there is a trend toward decreased recurrence in patients undergoing CNLD.
Fetal Bovine Serum Concentration Affects Δ9 Desaturase Activity of Trypanosoma cruzi
Authors: Villasuso Ana L. , Romero Patricio , Woelke Mariela , Moyano Patricia , Machado Estela , García de Lema Mirta
Published: February 2010

Fetal bovine serum (FBS) is an important factor in the culture of Trypanosoma cruzi, since this parasite obtains and metabolizes fatty acids (FAs) from the culture medium, and changes in FBS concentration reduce the degree of unsaturation of FAs in phosphoinositides. When T. cruzi epimastigotes were cultured with 5% instead of 10% FBS, and stearic acid was used as the substrate, ∆9 desaturase activity decreased by 50%. Apparent Km and Vm values for stearic acid, determined from Lineaweaver–Burk plots, were 2 μM and 219 pmol/min/mg of protein, respectively. In studies of the requirement for reduced pyridine nucleotide, ∆9 desaturase activity reached a maximum with 8 μM NADH and then remained constant; the apparent Km and Vm were 4.3 μM and 46.8 pmol/min/mg of protein, respectively. The effect of FBS was observed only for ∆9 desaturase activity; ∆12 desaturase activity was not affected. The results suggest that decreased FBS in culture medium is a signal that modulates ∆9 desaturase activity in T. cruzi epimastigotes.