bluuebunny/crossref_metadata_2025 huggingface dataset:
The preparation of novel silica modified polyimide membranes: synthesis, characterization, and gas separation properties
Authors: Boroglu Mehtap Safak , Gurkaynak Mehmet Ali
Published: September 2009

In this study, new monomers having siloxane groups were synthesized as an intermediate for preparation of siloxane modified polyimide polymers. Then with these monomers, the synthesis of uncrosslinked and crosslinked polyimide–siloxane hybrid polymer membranes were achieved. The purposes of the preparation of modified polyimides were to modify the thermal and chemical stability, and mechanical strength of polyimides, and to improve the gas separation properties of polymers. The new diamine monomer having siloxane groups was prepared from 3,5‐diaminobenzoic acid (3,5‐DABA) and 3‐aminopropyltrimethoxysilane (3‐APTMS) in N‐methyl‐2‐pyrollidone (NMP) at 180°C. The modified polyimide membranes having different amount of siloxane groups were synthesized from pyromellitic dianhydride (PMDA), 4,4‐oxydianiline (ODA), and 3,5‐diaminobenzamido‐N‐propyltrimethoxy silane (DABA/PTMS) in NMP using a two‐step thermal imidization process. The synthesis of modified polyimide membranes were characterized by Fourier transform infrared spectroscopy (FTIR). The thermal analysis of the polyimides were carried out by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Water absorption and swelling experiments were also carried out for the investigation of structural properties of polymers. FTIR observations confirmed that the polyimide membranes with new diamine intermediate were successfully obtained. Thermal analysis showed that the uncrosslinked copolyimides exhibited two glass transition temperatures, indicating that they were separated microphases and it was found that all the modified copolyimides had showed higher glass transition temperature (Tg) than unmodified polyimides. The separation properties of the prepared polyimide membranes were also characterized by permeability for O2 and N2 gases and ideal selectivity values were calculated. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of PLLA‐PEOMA comb‐block‐comb type molecular brushes based on AGET ATRP and ring‐opening polymerization
Authors: Wu Dongxia , Zhao Chuanzhuang , Tian Jia , Zhao Hanying
Published: September 2009

BACKGROUND: Molecular brushes are types of macromolecules with densely grafted side chains on a linear backbone. The synthesis of macromolecular brushes has stimulated much interest due to their great potential in applications in various fields. Poly(L‐lactide)–poly(ethylene glycol) methyl ether methacrylate (PLLA‐PEOMA) comb‐block‐comb molecular brushes with controlled molecular weights and narrow molecular weight distributions were successfully synthesized based on a combination of activator generated by electron transfer (AGET) atom transfer radical polymerization (ATRP) and ring‐opening polymerization. The synthetic route is a combination of the ‘grafting through’ method for AGET ATRP of the PEOMA comb block and the ‘grafting from’ method for the synthesis of the PLLA comb block. Poly(2‐hydroxyethyl methacrylate) (PHEMA) was synthesized by ATRP, and PLLA side chains and PEOMA side chains were grown from the backbones and the terminal sites of PHEMA, respectively.

RESULTS: The number‐average degrees of polymerization of PLLA chains and poly[poly(ethylene glycol) methyl ether methacrylate] (PPEOMA) comb blocks were determined using 1H NMR spectroscopy, and the apparent molecular weights and molecular weight distributions of the brush molecules were measured using gel permeation chromatography. The crystallization of the components in the comb‐block‐comb copolymers was also investigated. The crystallization of PLLA side chains is influenced by PLLA chain length and the content of PPEOMA in the molecular brushes. The comb‐block‐comb copolymer composed of hydrophobic PLLA and hydrophilic PEOMA can self‐assemble into a micellar structure in aqueous solution.

CONCLUSION: A combination of AGET ATRP and ring‐opening polymerization is an efficient method to prepare well‐defined comb‐block‐comb molecular brushes. The physical properties of the molecular brushes are closely related to their structures. Copyright © 2009 Society of Chemical Industry
Crosslinking of mixtures of diglycidylether of bisphenol‐A with 1,6‐dioxaspiro[4.4] nonan‐2,7‐dione initiated by tertiary amines: III. Effect of hydroxyl groups on network formation
Authors: Fernández‐Francos Xavier , Cook Wayne D , Salla Josep M , Serra Àngels , Ramis Xavier
Published: September 2009

BACKGROUND: Blends of epoxy resin oligomers, diglycidylether of bisphenol‐A (DGEBA), and a bislactone, 1,6‐dioxaspiro[4.4]nonan‐2,7‐dione (s(γBL)), were anionically copolymerized using two tertiary amines as anionic initiators. Their curing rheology and gelation behaviour were studied to provide a more comprehensive knowledge of the curing of these previously studied systems.

RESULTS: The activation energy for gelation was found to be similar to that previously measured using differential scanning calorimetry and appeared to increase in the presence of the bislactone. The reaction rate during copolymerization of DGEBA with s(γBL) was slower than DGEBA homopolymerization alone because the alkoxide attack on the epoxide is faster than the reaction of the carboxylate ion and the epoxy group. The effect of the initiator type on the gel conversion was small and was presumably due to differences in the kinetic chain length caused by amine regeneration from the quaternary amine. For the same initiator and at a constant ratio of DGEBA/s(γBL), an increase in the hydroxyl concentration of the DGEBA oligomer raised the gel conversion. For a DGEBA oligomer with low hydroxyl levels, an increase in the concentration of s(γBL) increased the gel conversion; however, for a DGEBA oligomer with high hydroxyl levels, increasing s(γBL) concentration decreased the gel conversion.

CONCLUSION: These results are interpreted in terms of the effect of initiation rate and chain transfer rate on the kinetic chain length. The glass transition temperature of the gel was found to be controlled by the fraction of the aliphatic s(γBL) and the amount of plasticizing sol in the matrix. Copyright © 2009 Society of Chemical Industry
Polyaniline–vanadium oxide hybrid hierarchical architectures assembled from nanoscale building blocks by homogeneous polymerization
Authors: Zhang Chuanqin , Wang Li , Peng Hongrui , Chen Kezheng , Li Guicun
Published: September 2009

BACKGROUND: Polyaniline–vanadium oxide hybrid materials have been much researched due to their potential applications in lithium batteries. Although many methods have been reported for the fabrication of conventional polyaniline–vanadium oxide hybrid materials by in situ oxidative polymerization/intercalation of aniline in V2O5 and by layer‐by‐layer approaches, studies on polyaniline–vanadium oxide hybrid nanostructures have been rare.

RESULTS: Polyaniline–vanadium oxide hybrid hierarchical architectures assembled from nanoscale building blocks, such as nanoplates and nanobelts, have been synthesized by a one‐step hydrothermal homogeneous reaction between aniline and peroxovanadic acid without the aid of any surfactant or template. The influences of synthesis parameters, i.e. reaction time, temperature and medium, on the morphologies of the polyaniline–vanadium oxide hybrid nanostructures have been investigated. With increasing reaction time/temperature, the alignment of nanoplates in the hierarchical architectures becomes gradually dense.

CONCLUSION: The formation mechanism of the polyaniline–vanadium oxide hybrid hierarchical architectures involves a one‐step precipitation–polymerization–assembly process. The method may be applicable for the synthesis of other conducting polymer–vanadium oxide hybrid nanostructures. Copyright © 2009 Society of Chemical Industry
A three‐way proteomics strategy allows differential analysis of yeast mitochondrial membrane protein complexes under anaerobic and aerobic conditions
Authors: Helbig Andreas O. , de Groot Marco J. L. , van Gestel Renske A. , Mohammed Shabaz , de Hulster Erik A. F. , Luttik Marijke A. H. , Daran‐Lapujade Pascale , Pronk Jack T. , Heck Albert J. R. , Slijper Monique
Published: September 2009

To investigate the effect of anaerobiosis on the Saccharomyces cerevisiae mitochondrial proteome and the formation of respiratory chain and other protein complexes, we analyzed mitochondrial protein extracts that were enriched from lysates of aerobic and anaerobic steady‐state chemostat cultures. We chose an innovative approach in which native mitochondrial membrane protein complexes were separated by 1‐D blue native PAGE, which was combined with quantitative analysis of each complex subunit using stable isotope labeling. LC‐FT(ICR)‐MS/MS analysis was applied to identify and quantify the mitochondrial proteins. In addition, to establish if changes in mitochondrial complex composition occurred under anaerobiosis, we investigated the 1‐D blue native PAGE protein migration patterns by Pearson correlation analysis. Surprisingly, we discovered that under anaerobic conditions, where the yeast respiratory chain is not active, the respiratory chain supercomplexes, such as complex V dimer, complex (III)2(IV)2 and complex (III)2(IV) were still present, although at reduced levels. Pearson correlation analysis showed that the composition of the mitochondrial complexes was unchanged under aerobic or anaerobic conditions, with the exception of complex II. In addition, this latter approach allowed screening for possible novel complex interaction partners, since for example protein Aim38p, with a yet unknown function, was identified as a possible component of respiratory chain complex IV.
Y‐shaped diblock copolymer with epoxy‐based block of poly(glycidyl methacrylate): Synthesis, characterization, and its morphology study
Authors: Zhang Bao , Li Yapeng , Ai Peng , Sa Zhongpeng , Zhao Yili , Li Meng , Wang Di , Sha Ke
Published: September 2009

A Y‐shaped diblock copolymer with a functional block poly(glycidyl methacrylate) was synthesized via the combination of enzymatic ring‐opening polymerization (eROP) and atom transfer radical polymerization (ATRP). The synthetic procedure involved eROP of ε‐caprolactone (ε‐CL) in the presence of biocatalyst Novozyme 435 and initiator 1H,1H,2H,2H‐perfluoro‐1‐octaoxy, subsequently the resulting poly(ε‐caprolactone) (PCL) was converted to a macroinitiator by esterification of it with 2,2‐dichloro acetyl chloride, and finally the ATRP of glycidyl methacrylate (GMA) was conducted at 60 °C with CuCl/2,2′‐bipyridine as the catalyst system. By this process, we obtained copolymers with a controlled molecular weight and a low polydispersity. The structure and composition of the obtained polymers were characterized by H NMR, GPC, and IR. Linear first‐order kinetics, linearly increased molecular weight with conversion, and low polydispersities were observed for the ATRP of GMA. The thermal properties of the copolymer were characterized by differential scanning calorimetry. The self‐assembly behavior of the Y‐shaped block copolymer was also investigated in different solvents and at different concentrations. The aggregates of various morphologies (spheres, worm‐like patterns, nanowell patterns, and dendritic patterns) were observed. It was found that solvents remarkably influenced the morphologies of the films spin‐coated from the corresponding solutions. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5509–5526, 2009
Creating Anti‐Reflective Nanostructures on Polymers by Initial Layer Deposition before Plasma Etching
Authors: Wendling Irmina , Munzert Peter , Schulz Ulrike , Kaiser Norbert , Tünnermann Andreas
Published: September 2009

The generation of nanostructures by initial layer deposition and plasma etching offers a simple and cost‐effective method for imparting broadband anti‐reflection properties to polymer optics. In this study, we have investigated the possibility of controlling the structure growth on the cycloolefin polymer Zeonex®. It has been found that the geometry of the emerging nanostructures can be adjusted from “island‐like,” through “sponge‐like,” to “pinholes” merely by changing the thickness of the initial layer before the etching step. However, not all structure types provided a satisfactory transmittance enhancement. Only when the initial layer thickness and the etching time were matched in such a way that a certain material/air filling factor range and a sufficient structure depth were obtained could an outstanding anti‐reflection effect be realized.
Retraction: Controllable Fabricate Intrinsic Fluorescent Polymer Nanoparticles Array by Atmospheric Pressure Plasma Polymerization
Authors: Yang Ping , Dai Xiujuan J. , Lamb Peter R. , Guo Ying , Xu Jinzhou , Ke Ding , Shi Jianjun , Zhang Jing
Published: September 2009

This article has been retracted: Controllable Fabricate Intrinsic Fluorescent Polymer Nanoparticles Array by Atmospheric Pressure Plasma Polymerization (Plasma Process. Polym. 2009, DOI: 10.1002/ppap.200950007)
Characterization of intrinsically disordered proteins with electrospray ionization mass spectrometry: Conformational heterogeneity of α‐synuclein
Authors: Frimpong Agya K. , Abzalimov Rinat R. , Uversky Vladimir N. , Kaltashov Igor A.
Published: September 2009

Conformational heterogeneity of α‐synuclein was studied with electrospray ionization mass spectrometry by analyzing protein ion charge state distributions, where the extent of multiple charging reflects compactness of the protein conformations in solution. Although α‐synuclein lacks a single well‐defined structure under physiological conditions, it was found to sample four distinct conformational states, ranging from a highly structured one to a random coil. The compact highly structured state of α‐synuclein is present across the entire range of conditions tested (pH ranging from 2.5 to 10, alcohol content from 0% to 60%), but is particularly abundant in acidic solutions. The only other protein state populated in acidic solutions is a partially folded intermediate state lacking stable tertiary structure. Another, more compact intermediate state is induced by significant amounts of ethanol used as a co‐solvent and appears to represent a partially folded conformation with high β‐sheet content. Protein dimerization is observed throughout the entire range of conditions tested, although only acidic solutions favor formation of highly structured dimers of α‐synuclein. These dimers are likely to present the earliest stages in protein aggregation leading to globular oligomers and, subsequently, protofibrils. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Holo‐BtuF stabilizes the open conformation of the vitamin B12 ABC transporter BtuCD
Authors: Kandt Christian , Tieleman D. Peter
Published: September 2009

While there is evidence that other ABC transporters can tell between empty and loaded substrate binding protein, reconstitution experiments suggest otherwise for the Escherichia coli vitamin B12 importer BtuCD‐F. Here, we address the question of BtuCD‐F substrate sensitivity in a combined protein–protein docking and molecular dynamics simulation approach. Starting from the BtuCD and holo‐BtuF crystal structures, we model two holo‐BtuCD‐F docking complexes differing by a 180° orientation of BtuF. One of these is similar to the apo‐BtuCD‐F crystal structure. Both docking complexes were embedded in a lipid/water environment to investigate their dynamics and BtuCD's conformational response to the presence and absence of BtuF, vitamin B12, and Mg‐ATP in a series of 28 independent MD simulations. We find holo‐BtuF stabilizing the open conformation of BtuCD, whereas the transporter begins to close again when BtuF or vitamin B12 is removed—suggesting BtuCD‐F is capable of substrate sensitivity. We identified BtuC transmembrane helices 3 and 5, the L‐loops and the adjacent helices comprised of BtuC residues 170–180 as hotspots of conformational change. We propose the latter to act as substrate sensors. BtuF‐Trp44 appears to act as a lid on the vitamin B12 binding cleft in BtuF X‐ray structures and protrudes into the BtuCD transport channel in one of our simulations, which might represent an initial step in vitamin B12 uptake. On an average, we observe subunit motions where the nucleotide binding domains approach each other while the transmembrane domains display an opening trend toward the periplasm. Proteins 2010. © 2009 Wiley‐Liss, Inc.
Internet security meets the IP multimedia subsystem: an overview
Authors: Berger Andreas , Gojmerac Ivan , Jung Oliver
Published: September 2009

In this paper, we discuss the security threats of next‐generation telecommunication core networks induced by the adoption of Internet technology. The 3GPP IP multimedia subsystem (IMS) is based on the Internet protocol (IP) and hence inherits many security problems from the Internet world. We provide a review of the most prominent vulnerabilities, covering both fundamental functions like routing and name resolution as well as message tampering and implementation attacks, and we show their impact on the IMS. Further, we address the topics of denial of service (DoS) attacks and unsolicited communication (UC). Despite the large number of security threats, the IMS standardization foresees no security monitoring and fully relies on standard countermeasures as known from the Internet. This paper provides a survey of these threats and relates them to the available solutions. We motivate the need for a powerful and modular monitoring platform for the IMS and provide an overview of the existing work in this research field. Copyright © 2009 John Wiley & Sons, Ltd.
The use of an interim CEO during succession episodes and firm performance
Authors: Ballinger Gary A. , Marcel Jeremy J.
Published: September 2009

Our study investigates an unexplored succession process—interim CEO successions. We define an interim CEO succession as a case where the title of chief executive officer is vacated by the incumbent and the board of directors has not announced a permanent successor, but instead designates a particular individual as ‘interim CEO,’ or ‘acting CEO,’ or ‘CEO until a permanent successor is named.’ Theory predicts that interim CEO successions will lead to the type of disruption that can harm firm performance, even after a permanent successor is appointed. Our data show that interim CEO succession processes are widely employed by publicly‐traded U.S. firms, and that they are associated with lower performance during the period in which the interim serves. However, whether the interim CEO also simultaneously serves as chairman moderates the impact of this type of succession on firm performance, as well as on long‐term firm survival. Copyright © 2009 John Wiley & Sons, Ltd.
The routine may be stable but the advantage is not: competitive implications of key employee mobility
Authors: Aime Federico , Johnson Scott , Ridge Jason W. , Hill Aaron D.
Published: September 2009

We extend our theoretical understanding of the effect of key employee mobility on organizational performance. We find that when an organization with an advantageous set of routines loses a key employee to a competitor, the advantaged organization's competitive position is reduced vis‐à‐vis the hiring competitor. What is more interesting is that we also show that the diffusion of an advantageous set of routines through the mobility of key employees may affect competitive advantage in at least two additional ways. Our findings result from an analysis of 412 competitive events between the San Francisco 49ers and all other teams in the National Football League during the 24‐year period when the San Francisco 49ers perfected the routines of a strategic innovation that has become known as the West Coast Offense. First, we find that there is a loss of advantage for the organization when competitors increasingly compete against additional organizations that hired key employees from it. Second, we find that there is a loss of advantage for the organization when competitors expect future competition against additional organizations that hired key employees from it. Our results challenge the traditional argument that socially complex routines create sustainable competitive advantages because they are not easily imitated and do not rely on any single individual. Instead, we show that routines are stable to the loss of key employees, but the advantages derived from them are not. Copyright © 2009 John Wiley & Sons, Ltd.
Direct Imaging of Immune Rejection and Memory Induction by Allogeneic Mesenchymal Stromal Cells
Authors: Zangi Lior , Margalit Raanan , Reich-Zeliger Shlomit , Bachar-Lustig Esther , Beilhack Andreas , Negrin Robert , Reisner Yair
Published: September 2009

Although mesenchymal stromal cells (MSCs) exhibit marked immunoregulatory activity through multiple mechanisms, their potential to completely evade rejection upon transplantation into allogeneic recipients is controversial. To directly address this controversy, the survival of luciferase-labeled MSCs (Luc+ MSCs) was evaluated by imaging in allogeneic recipients. This analysis showed that although MSCs exhibited longer survival compared to fibroblasts (Fib), their survival was significantly shorter compared to that exhibited in syngeneic or in immune-deficient Balb-Nude or non-obese diabetic severe combined immunodeficiency (NOD-SCID) recipients. Graft rejection in re-challenge experiments infusing Luc+ Fib into mice, which had previously rejected Luc+ MSCs, indicated potential induction of immune memory by the MSCs. This was further analyzed in T-cell antigen receptor (TCR) transgeneic mice in which either CD4 TEA mice or CD8 T cells (2C mice) bear a TCR transgene against a specific MHC I or MHC II, respectively. Thus, following a re-challenge with MSCs expressing the cognate MHC haplotype, an enhanced percentage of 2C CD8+ or TEA CD4+ T cells exhibited a memory phenotype (CD122+, CD44+, and CD62Llow). Collectively, these results demonstrate that MSCs are not intrinsically immune-privileged, and under allogeneic settings, these cells induce rejection, which is followed by an immune memory. Considering that the use of allogeneic or even a third party (“off the shelf”) MSCs is commonly advocated for a variety of clinical applications, our results strongly suggest that long-term survival of allogeneic MSCs likely represents a major challenge.

Disclosure of potential conflicts of interest is found at the end of this article.
Yeast Ste23p shares functional similarities with mammalian insulin‐degrading enzymes
Authors: Alper Benjamin J. , Rowse Jarrad W. , Schmidt Walter K.
Published: September 2009

The S. cerevisiae genome encodes two M16A enzymes: Axl1p and Ste23p. Of the two, Ste23p shares significantly higher sequence identity with M16A enzymes from other species, including mammalian insulin‐degrading enzymes (IDEs). In this study, recombinant Ste23p and R. norvegicus IDE (RnIDE) were isolated from E. coli, and their enzymatic properties compared. Ste23p was found to cleave established RnIDE substrates, including the amyloid‐β peptide (Aβ1–40) and insulin B‐chain. A novel internally quenched fluorogenic substrate (Abz–SEKKDNYIIKGV–nitroY‐OH) based on the polypeptide sequence of the yeast P2 a‐factor mating propheromone was determined to be a suitable substrate for both Ste23p and RnIDE, and was used to conduct comparative enzymological studies. Both enzymes were most active at 37 °C, in alkaline buffers and in high salt environments. In addition, the proteolytic activities of both enzymes towards the fluorogenic substrate were inhibited by metal chelators, thiol modifiers, inhibitors of cysteine protease activity and insulin. Characteristics of STE23 expression were also evaluated. Our analysis indicates that the 5′ terminus of the STE23 gene has been mischaracterized, with the physiologically relevant initiator corresponding to residue M53 of the publicly annotated protein sequence. Finally, we demonstrate that, unlike haploid‐specific Axl1p, Ste23p is expressed in both haploid and diploid cell types. Our study presents the first comprehensive biochemical analysis of a yeast M16A enzyme, and provides evidence that S. cerevisiae Ste23p has enzymatic properties that are highly consistent with mammalian IDEs and other M16A enzymes. Copyright © 2009 John Wiley & Sons, Ltd.
Zinc‐finger intron 7: a new locus for sex identification of giant panda (Ailuropoda melanoleuca)
Authors: Xu Xiao , Li Yuzhi , Wang Xiaofang , Wei Kun , Zhang Wenping , Zhang Zhihe , Shen Fujun , Yue Bisong
Published: September 2009

We developed a single‐reaction test for identifying the sex of giant panda (Ailuropoda melanoleuca) targeted to co‐amplify homologous fragments with size polymorphism that located at zinc‐finger (ZF) intron 7 by using one pair of primers. This assay produced one sex‐specific fragment in females (XX genotypes) whereas two fragments were produced in males (XY genotypes). Indels (insertion/deletion) in intron 7 of Y‐linked allele provide a significant discrimination between ZFX and ZFY, thus the amplification products can be simply distinguished by agarose gel electrophoresis, exhibiting sex‐specific banding patterns (female, 354 bp; male, 354 bp, 135 bp). The new primer set was successfully tested on known‐sex giant pandas by using template DNA extracted from both blood and fecal samples. Cross‐species test was also performed, revealing that this assay could be applied to other Ursidae species. Zoo Biol 29:526–531, 2010. © 2009 Wiley‐Liss, Inc.
To pay or not to pay? Monitoring performance and enforcing conditionality when paying for forest conservation in Mexico
Authors: HONEY-ROSÉS JORDI , LÓPEZ-GARCÍA JOSÉ , RENDÓN-SALINAS EDUARDO , PERALTA-HIGUERA ARMANDO , GALINDO-LEAL CARLOS
Published: September 2009

Paying landowners to conserve forests is a promising new strategy to protect biodiversity and ecosystem services. However to succeed with this approach, programme managers need reliable monitoring data to make informed payment decisions. This includes withholding payment from landowners who do not meet conservation objectives. The monitoring method used for the Monarch Butterfly Conservation Fund compared aerial photographs and conducted field sampling to identify forest changes. The comparison of aerial photographs showed that 161 hectares of forest were degraded in the central core zone of the Monarch Butterfly Biosphere Reserve in Mexico between 2001 and 2003. As a result, payment was withheld from one of 13 landowners. Analysis of high resolution (0.6 m) digital aerial photographs did not detect finer scale changes, despite obtaining an average pixel resolution 1000 times greater than Landsat satellite imagery. This suggests that current payment for ecosystem services programmes are underestimating environmental change and overpaying non-compliant participants. In addition, selecting a decision rule to enforce payment conditionality raised new questions about how much ecosystem degradation should be permitted before withholding payment. Sound decisions about withholding payment cannot be developed until the marginal value of ecosystem services is better understood. Until then, payment thresholds can be based on specific policy objectives.
Dietary patterns associated with metabolic syndrome, sociodemographic and lifestyle factors in young adults: the Bogalusa Heart Study
Authors: Deshmukh-Taskar Priya R , O’Neil Carol E , Nicklas Theresa A , Yang Su-Jau , Liu Yan , Gustat Jeanette , Berenson Gerald S
Published: September 2009

Objective

To examine the association between dietary patterns (DP) and risk for metabolic syndrome (MetS); and to identify differences in DP by socio-economic, demographic and lifestyle factors.

Design

Dietary intake (from an FFQ), anthropometric/biochemical parameters and sociodemographic/lifestyle information (from a self-reported questionnaire) were evaluated, using a cross-sectional design. Statistical methods included principal component factor analysis, analysis of covariance and linear regression. All analyses were covariate-adjusted.

Setting

The Bogalusa Heart Study (1995–1996), USA.

Subjects

Young adults (19–39 years; n 995; 61 % females/39 % males; 80 % whites/20 % blacks) from a semi-rural southern US community were examined.

Results

The ‘Western Dietary Pattern’ (WDP) consisted of refined grains, French fries, high-fat dairy foods, cheese dishes, red meats, processed meats, eggs, snacks, sweets/desserts, sweetened beverages and condiments. The ‘Prudent Dietary Pattern’ (PDP) consisted of whole grains, legumes, vegetables, fruits, 100 % fruit juices, low-fat dairy products, poultry, clear soups and low-fat salad dressings. The DP explained 31 % of the dietary intake variance. Waist circumference (P = 0·02), triceps skinfold (P = 0·01), plasma insulin (P = 0·03), serum TAG (P = 0·05), and the occurrence of MetS (P = 0·03) were all inversely associated with PDP. Insulin sensitivity (P < 0·0005) was positively associated with PDP. Serum HDL cholesterol (P = 0·05) was inversely associated with WDP. Blacks consumed more servings from WDP than whites (P = 0·02). Females consumed more servings from PDP than males (P = 0·002). Those with >12 years of education consumed more servings from PDP than their counterparts (P < 0·0001). Current smokers consumed more servings from WDP than current non-smokers (P < 0·0001). Physically very active young adults consumed fewer servings from WDP than their sedentary counterparts (P = 0·02).

Conclusions

More studies are warranted to confirm these findings in other populations.
Mental Health Policy in Northern Ireland: The Nature and of Extent of User Involvement
Authors: Heenan Deirdre
Published: September 2009

In a recent review of the mental health policies of its 42 member states in the European Region, the World Health Organization highlighted the need for further analysis of service user involvement in the policy making process. In the UK, a plethora of recent government policies and initiatives have stressed the importance of service user involvement in the design and delivery of health and social services. Their input is described as a fundamental requirement of a modern, flexible, responsive healthcare system. This paper reviews mental health policy in Northern Ireland, which has undergone a period of unprecedented activity and explores the extent to which service users have influenced the process of policy design and development. It raises questions about the extent to which a genuine commitment to and investment in user involvement has been achieved and comments on the prospects for the future.
Screening and Brief Intervention for Alcohol use in a Custody Suite: The Shape of Things to Come?
Authors: Barton Adrian , Squire Greta , Patterson Mark
Published: September 2009

Irresponsible and excessive consumption of alcohol and the associated problems it carries in its wake have become one of the key concerns for central government both in terms of community safety and public health. In response to the Alcohol Harm Reduction Strategy for England (DoH, 2007), the Department of Health (DoH) have announced a series of measures, one of which is to pilot screening and intervention for alcohol use programmes in a variety of locations, of which one is within a probation setting. This paper reports on the findings of a project that pre-empts the DoH initiatives, thus providing the opening comments in what is sure to be a debate about a new strategic and evidence-based approach to dealing with problematic alcohol use. The paper provides data and discussions on the Screening and Brief Intervention (SBI) project that screened 3,900 detainees in the Charles Cross custody suite in Plymouth, England during the period March 2007 to March 2008.
Introduction: Themed section on Children's Perspectives on Poverty and Disadvantage in Rich and Developing Countries
Authors: Ridge Tess , Saunders Peter
Published: September 2009

The purpose of this themed section is to bring together a set of papers that highlight children's perspectives of poverty and disadvantage. The articles selected explore the experiences, paid and unpaid resource contributions, and perspectives of children who face economic adversity in different countries across a range of diverse settings. They reveal some of the complexity of children's lives using different methodological approaches drawn from a spectrum of qualitative research with disadvantaged children that is growing and changing as it responds to new and innovative ways of engaging with children. The themed section includes findings from a qualitative longitudinal study in the UK, findings from a survey of children's views in Norway that includes a qualitative component, and snapshots across time from seven years of research with working children in Indonesia. These papers, coupled with an extensive review of the growing body of literature on children's perspectives on poverty present a valuable insight into a developing field of research.
Family Income and Children's Perception of Parental Support and Monitoring
Authors: Sandbæk Mona
Published: September 2009

Family relations have for many years been acknowledged as having a protective impact on children's development if positive and as representing a risk factor if negative. Studies based on statistical information have demonstrated an overrepresentation of a number of family problems in low-income families. Does this image change with children themselves as informants on child–parent relationships? The article examines Norwegian children's perception of parental acceptance, support and monitoring in low-income families compared to children living in families from all income groups.
Role of off‐shelf to on‐shelf transitions for East Antarctic sea ice dynamics during spring 2003
Authors: Heil Petra , Massom Robert A. , Allison Ian , Worby Anthony P. , Lytle Victoria I.
Published: September 2009

During austral spring 2003, mesoscale sea ice drift and deformation off East Antarctica were investigated using in situ data from a nine‐buoy array. Upon deployment, the array comprised an area of about 4000 km2 with a mean ice concentration of 96%. Half‐hourly sea ice velocities were coherent across all buoys at zonal (meridional) separations of less than 160 km (70 km). Regional cross‐spectral correlation was high at synoptic scales and also at semidiurnal periods off the continental shelf. Atmospheric synoptic‐scale forcing explained in excess of 85% of the ice drift variability. This is significantly more than found in the Weddell Sea, where significant ice drift variability is derived from oceanic forcing. Peak frequencies of semidiurnal contributions covaried with latitude and are largely associated with the inertial response. Over the continental shelf, coincident diurnal and semidiurnal variances in ice motion arose from tidal forcing. Net divergence over 37 days resulted in an expansion to 270% of the initial area, although regional ice concentration reduced only slightly. High‐frequency processes, namely inertial response and to a lesser degree tidal forcing, dominated the variability of all deformation parameters. In contrast to ice motion, low‐frequency processes played a secondary role in sea ice deformation. This high‐frequency dominance is similar to what has been found in the Weddell Sea, although many observations there were limited to the continental shelf, where tidal processes dominate. Sea ice motion and deformation were not affected by a seasonal transition, nor did the regional ice characteristics show any signal of seasonal change. Instead, local ice dynamics were strongly influenced by bathymetrically dependent processes.
Determination of earthquake focal depths and source time functions in central Asia using teleseismic P waveforms
Authors: Chu Risheng , Zhu Lupei , Helmberger Don V.
Published: September 2009

We developed a new method to determine earthquake source time functions and focal depths. It uses theoretical Green's function and a time‐domain deconvolution with positivity constraint to estimate the source time function from the teleseismic P waveforms. The earthquake focal depth is also determined in the process by using the time separations of the direct P and depth phases. We applied this method to 606 earthquakes between 1990 and 2005 in Central Asia. The results show that the Centroid Moment Tensor solutions, which are routinely computed for earthquake larger than M5.0 globally using very long period body and surface waves, systematically over‐estimated the source depths and durations, especially for shallow events. Away from the subduction zone, most of the 606 earthquakes occurred within the top 20 km of crust. This shallow distribution of earthquakes suggests a high geotherm and a weak ductile lower crust in the region.
Mercury volatilization from salt marsh sediments
Authors: Smith Lora M. , Reinfelder John R.
Published: September 2009

In situ volatilization fluxes of gaseous elemental mercury, Hg(0), were estimated for tidally exposed salt marsh sediments in the summer at the urban/industrial Secaucus High School Marsh, New Jersey Meadowlands (Secaucus, New Jersey) and in the early autumn at a regional background site in the Great Bay estuary (Tuckerton, New Jersey). Estimated daytime sediment‐air mercury volatilization fluxes at the Secaucus High School Marsh ranged from −375 to +677 ng m−2 h−1 and were positive (land to air flux) in 16 out of 20 measurement events. At the Great Bay estuary, mercury fluxes measured continuously over a 48‐h period ranged from −34 to +81 ng m−2 h−1 and were positive during the day and negative at night. At both sites, mercury volatilization fluxes peaked at midday, and cumulative mercury fluxes exhibited strong positive correlations with cumulative solar radiation (r2 = 0.97, p < 0.01) consistent with a light‐driven mercury volatilization efficiency of about 15 ng Hg mol PAR−1 or about 0.06 ng Hg kJ−1. No significant correlations were found between mercury fluxes and wind speed, air temperature, or tide height at either site. Thus despite a tenfold difference in sediment mercury concentration, photochemistry appears to be the dominant factor controlling mercury volatilization from these salt marsh sediments. The average mercury volatilization flux estimated for the Great Bay salt marsh in this study (17 ng m−2 h−1) compares well with other micrometeorological mercury fluxes for nonpoint source contaminated salt marsh and forest soils (8–18 ng m−2 h−1) and is more than 10 times higher than the average mercury emission flux from land (∼1 ng m−2 h−1). Annual mercury emissions from salt marsh wetlands may be comparable to individual industrial emissions sources in coastal states of the eastern United States.
Histomorphometric characteristics and expression of epidermal growth factor and its receptor by epithelial cells of normal gingiva and hereditary gingival fibromatosis
Authors: Araujo C. S. A. , Graner E. , Almeida O. P. , Sauk J. J. , Coletta R. D.
Published: September 2009

Objective:  The objective of this study was to examine the histomorphometric features and evaluate the expression of epidermal growth factor (EGF) and transmembranic receptor (EGFr) and the proliferative potential of epithelial cells from normal and hereditary gingival fibromatosis (HGF) gingival tissues.

Background:  EGF is a multifunctional cytokine with a variety of biological effects including stimulation of cell proliferation by binding to its specific EGFr.

Methods:  Immunohistochemistry was performed to measure EGF and EGFr expression and the epithelial cell proliferation was determined by measuring proliferating cell nuclear antigen (PCNA).

Results:  Histomorphometric evaluation indicated that in HGF the mean height of the epithelial papillae was higher compared to the normal gingiva (NG), whereas mean epithelial area and number of epithelial papillae were quite similar in both groups. The EGF and EGFr positive cells were observed in the basal, spinous and granular cell layers of both normal and HGF tissues, with a gradual reduction from the basal layer. Although the expressions of EGF and EGFr in the control group were significantly higher than those from HGF, in HGF the epithelial papilla tips showed increased number of proliferating cells and elevated expression of EGF and EGFr. There was a correlation between the proliferative potential of epithelial cells and the expression of EGF or EGFr only in the epithelial papilla tips of HGF gingiva.

Conclusion:  Our data suggest that EGF and EGFr in the oral epithelium of HGF gingiva may stimulate epithelial cell proliferation, with the resultant apical migration of the oral epithelium and formation of the slender deep epithelial papillae; however, without hyperplastic alterations.
Granulocyte elastase activity in static and flow gingival crevicular fluid
Authors: Jin Lijian , Yu Chun , Corbet Esmonde F.
Published: September 2009

Objectives:  This study aimed to evaluate the volume of gingival crevicular fluid (GCF) and granulocyte elastase activity in static GCF (sGCF) and flow GCF (fGCF) from subjects with various periodontal conditions.

Methods:  Eleven periodontally healthy, 10 gingivitis and 12 periodontitis subjects were recruited and the sites investigated consisted of healthy sites from healthy subjects (HH); healthy (HG) and gingivitis sites (GG) from gingivitis subjects; and healthy (HP), gingivitis (GP) and periodontitis sites (PP) from periodontitis subjects. fGCF samples were collected either 1 min or 5 min following sGCF collection by paper strip technique. GCF volume was determined by Periotron® 6000 and granulocyte elastase activity was assayed with a specific substrate [l‐pyroglutamyl‐l‐prolyl‐l‐valine‐p‐nitroanilide(pGluProVal‐pNA)].

Results:  At baseline, no significant differences existed in clinical and GCF parameters between the two matched sites for subsequent collection of fGCF samples either 1 min or 5 min after sGCF sampling in all subjects. The flow exudate in HG and HP sites quickly replenished to sGCF levels, while a delayed replenishment was found in HH sites, despite the similar sGCF volumes of these sites. The GCF volume and elastase levels in the fGCF at 1 min were higher in GP sites than in GG sites (P < 0.05). Overall, depletion of elastase levels in the fGCF at 1 min was observed in all subjects, whereas elastase levels in the fGCF at 5 min had replenished to sGCF levels in HP, GP, PP sites and GG sites, but had remained at a lower level in HH and HG sites. An overall positive correlation was found between sGCF and fGCF for GCF volume and elastase activity (P < 0.001); however, this correlation varied with GCF parameters and with site conditions of the subjects concerned.

Conclusions:  This study shows that patterns of dynamic changes in GCF flow and elastase activity varied under different periodontal conditions. Assessment of both sGCF and fGCF may allow better insight into the dynamic change of the target components in GCF.
Expression of endothelins and their receptors in cells from human periodontal tissues
Authors: Fujioka Daisuke , Nakamura Shigeo , Yoshino Hiroshi , Shinohara Hiroaki , Shiba Hideki , Mizuno Noriyoshi , Hasegawa Naohiko , Shindoh Norihisa , Uchida Yuushi , Ogawa Tetsuji , Kawaguchi Hiroyuki , Kurihara Hidemi
Published: September 2009

Objective: The present study investigated the presence of ET‐1 in gingival crevicular fluid (GCF) from patients with periodontitis, and the expression of endothelins (ETs) and their receptors mRNA in cultured cells from human periodontal tissues.

Background: ET was originally discovered as a potent vasoconstrictive peptide from endothelial cells. It has been reported that ETs are produced by various cells besides endothelial cells. ETs are related to inflammatory and sclerotic lesions, such as arteriolosclerosis and hepatic cirrhosis. Therefore, ETs may be involved in periodontal disease. However, the roles of ETs in development and progression of periodontal disease are not clear.

Methods: ET‐1 released from the cultured cells was measured by enzyme‐linked immunosorbent assay. mRNA expressions for ETs and their receptors were examined by reverse transcription‐polymerase chain reaction and Northern blotting analysis.

Results: ET‐1 levels in GCF from patients with periodontitis were higher than those from healthy subjects. Human gingival keratinocytes (HGK) expressed mRNA for ETs and their receptors, ET‐Ar and ET‐Br. ET‐1 mRNA expression and ET‐1 peptide production from HGK were enhanced by interleukin‐1β and tumor necrosis factor‐α.

Conclusions: These results suggest that ET‐1 plays a significant role in periodontal disease.
Serum antibody reactivity against recombinant PrtC of Porphyromonas gingivalis following periodontal therapy
Authors: Beikler T. , Ehmke B. , Wittstock M. , Schmidt H. , Karch H. , Flemmig T. F.
Published: September 2009

Objectives:  In 34 patients with chronic periodontitis, the presence of IgA, IgG, and IgG subclass serum antibodies against recombinant PrtC (rPrtC) of Porphyromonas gingivalis was assessed by immunoblot analysis 24 months after therapy.

Methods:  rPrtC was produced from P. gingivalis ATTC 33277 using the plasmid pGEX‐2T. In addition, intraoral colonization with P. gingivalis was detected by PCR in subgingival plaque and swab samples from buccal mucosae, tonsils and tongue at baseline, 10 d, and 3, 6, 9, 12, 18, and 24 months.

Results:  All patients were found to harbor P. gingivalis in the oral cavity at least once during the observation period. The identified antibody responses against the rPrtC of P. gingivalis were IgA (97%, i.e. 33/34 patients) and IgG (100%, i.e. 34/34), with an IgG subclass distribution of IgG2 (65%, i.e. 22/34 patients) > IgG3 (47%, i.e. 16/34) > IgG1 (38%, i.e. 13/34) > IgG4 (29%, i.e. 10/34). Anti‐rPrtC IgA and IgG antibody reactivity was found in all but one patients (anti‐rPrtC IgA negative), who tested negative for P. gingivalis at all of the assessed intraoral sites for at least 6 months before sera collection. There was no association between IgG subclass reactivity against the rPrtC of P. gingivalis and progression of periodontal attachment loss.

Conclusion:  The results indicated that anti‐rPrtC IgA and IgG antibodies may serve as an indicator for past or present intraoral colonization with P. gingivalis.
Inhibitory effect of procyanidin oligomer from elm cortex on the matrix metalloproteinases and proteases of periodontopathogens
Authors: Song Si‐Eun , Choi Bong‐Kyu , Kim Sang‐Nyun , Yoo Yun‐Jung , Kim Moon‐Moo , Park Sang‐Ki , Roh Seok‐Sun , Kim Chong‐Kwan
Published: September 2009

Objectives:  The purpose of this study was to evaluate a partially purified extract (elm extract) from the Ulmi cortex (Ulmi macrocarpa Hance) and its active ingredient, a mix of procyanidin oligomers (3 to 12 flavan‐3‐ol monomers, an average molecular weight of 1,518 with an average polymerization degree of 5.3) for a possible inhibitory effect against proteases.

Background:  Host‐derived matrix metalloproteinases (MMPs) and bacterial proteases play important roles in the gingival tissue destruction that is a characteristic of periodontitis. The inhibitors of these proteases may be developed into therapeutic agents against periodontitis.

Methods:  The inhibitory effects were assessed by gelatin zymography. The MMPs tested were originated from the gingival crevicular fluid (GCF) of adult periodontitis patients and from the conditioned media of cultured periodontal ligament (PDL) cells, which provided the proMMP‐2 and activated MMP‐2 when treated with a periodontopathogen, Treponema lecithinolyticum. Bacterial enzymes tested were secreted forms from two major periodontopathogens, Porphyromonas gingivalis and Treponema denticola. In addition, the inhibitory effects on trypsin‐like enzymes from these two periodontopathogens were assayed by the n‐benzoyl‐DL‐arginine‐naphthylamide (BANA) test.

Results:  The elm extract and the procyanidin oligomer (100‐1,000 μg/ml) exhibited potent inhibitory effects on the MMPs in GCF (chiefly MMP‐8 and MMP‐9), the pro and active forms of MMP‐2, and secreted and trypsin‐like enzymes from T. denticola and P. gingivalis.

Conclusions:  These results suggest that elm cortex should be considered as a potential agent against periodontal diseases, due to its inhibitory action on MMPs and the proteases of periodontopathogens.